Bacteriophage Tail-Tube Assembly Studied by Proton-Detected 4D Solid-State NMR

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

Zinke, Maximilian; Fricke, Pascal; Samson, Camille

Obtaining unambiguous resonance assignments remains a major bottleneck in solid-state NMR studies of protein structure and dynamics. Particularly for supramolecular assemblies with large subunits (>150 residues), the analysis of crowded spectral data presents a challenge, even if three-dimensional (3D) spectra are used. Here, we present a proton-detected 4D solid-state NMR assignment procedure that is tailored for large assemblies. The key to recording 4D spectra with three indirect carbon or nitrogen dimensions with their inherently large chemical shift dispersion lies in the use of sparse non-uniform sampling (as low as 2 %). As a proof of principle, we acquired 4D (H)COCANH,more » (H)CACONH, and (H)CBCANH spectra of the 20 kDa bacteriophage tail-tube protein gp17.1 in a total time of two and a half weeks. These spectra were sufficient to obtain complete resonance assignments in a straightforward manner without use of previous solution NMR data.« less

NMR spectra of 3β-hydroxy-5α-cholane derivatives, zymosterol synthesis intermediates

NASA Astrophysics Data System (ADS)

Baranovsky, A. V.; Bolotin, A. A.; Kiselev, V. P.

2011-05-01

Proton and carbon resonances in NMR spectra of a number of derivatives of 3β-hydroxy-5α-cholanes, zymosterol synthesis intermediates, have been completely assigned using 2D NMR spectroscopy methods. The stereochemistry of the chiral centers and the structures of the molecules have been confirmed.

A new algorithm for reliable and general NMR resonance assignment.

PubMed

Schmidt, Elena; Güntert, Peter

2012-08-01

The new FLYA automated resonance assignment algorithm determines NMR chemical shift assignments on the basis of peak lists from any combination of multidimensional through-bond or through-space NMR experiments for proteins. Backbone and side-chain assignments can be determined. All experimental data are used simultaneously, thereby exploiting optimally the redundancy present in the input peak lists and circumventing potential pitfalls of assignment strategies in which results obtained in a given step remain fixed input data for subsequent steps. Instead of prescribing a specific assignment strategy, the FLYA resonance assignment algorithm requires only experimental peak lists and the primary structure of the protein, from which the peaks expected in a given spectrum can be generated by applying a set of rules, defined in a straightforward way by specifying through-bond or through-space magnetization transfer pathways. The algorithm determines the resonance assignment by finding an optimal mapping between the set of expected peaks that are assigned by definition but have unknown positions and the set of measured peaks in the input peak lists that are initially unassigned but have a known position in the spectrum. Using peak lists obtained by purely automated peak picking from the experimental spectra of three proteins, FLYA assigned correctly 96-99% of the backbone and 90-91% of all resonances that could be assigned manually. Systematic studies quantified the impact of various factors on the assignment accuracy, namely the extent of missing real peaks and the amount of additional artifact peaks in the input peak lists, as well as the accuracy of the peak positions. Comparing the resonance assignments from FLYA with those obtained from two other existing algorithms showed that using identical experimental input data these other algorithms yielded significantly (40-142%) more erroneous assignments than FLYA. The FLYA resonance assignment algorithm thus has the reliability and flexibility to replace most manual and semi-automatic assignment procedures for NMR studies of proteins.

Automated and assisted RNA resonance assignment using NMR chemical shift statistics

PubMed Central

Aeschbacher, Thomas; Schmidt, Elena; Blatter, Markus; Maris, Christophe; Duss, Olivier; Allain, Frédéric H.-T.; Güntert, Peter; Schubert, Mario

2013-01-01

The three-dimensional structure determination of RNAs by NMR spectroscopy relies on chemical shift assignment, which still constitutes a bottleneck. In order to develop more efficient assignment strategies, we analysed relationships between sequence and 1H and 13C chemical shifts. Statistics of resonances from regularly Watson–Crick base-paired RNA revealed highly characteristic chemical shift clusters. We developed two approaches using these statistics for chemical shift assignment of double-stranded RNA (dsRNA): a manual approach that yields starting points for resonance assignment and simplifies decision trees and an automated approach based on the recently introduced automated resonance assignment algorithm FLYA. Both strategies require only unlabeled RNAs and three 2D spectra for assigning the H2/C2, H5/C5, H6/C6, H8/C8 and H1′/C1′ chemical shifts. The manual approach proved to be efficient and robust when applied to the experimental data of RNAs with a size between 20 nt and 42 nt. The more advanced automated assignment approach was successfully applied to four stem-loop RNAs and a 42 nt siRNA, assigning 92–100% of the resonances from dsRNA regions correctly. This is the first automated approach for chemical shift assignment of non-exchangeable protons of RNA and their corresponding 13C resonances, which provides an important step toward automated structure determination of RNAs. PMID:23921634

Probing cis-trans isomerization in the S{sub 1} state of C{sub 2}H{sub 2} via H-atom action and hot band-pumped IR-UV double resonance spectroscopies

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

Changala, P. Bryan; Baraban, Joshua H.; Field, Robert W., E-mail: rwfield@mit.edu

2015-08-28

We report novel experimental strategies that should prove instrumental in extending the vibrational and rotational assignments of the S{sub 1} state of acetylene, C{sub 2}H{sub 2}, in the region of the cis-trans isomerization barrier. At present, the assignments are essentially complete up to ∼500 cm{sup −1} below the barrier. Two difficulties arise when the assignments are continued to higher energies. One is that predissociation into C{sub 2}H + H sets in roughly 1100 cm{sup −1} below the barrier; the resulting quenching of laser-induced fluorescence (LIF) reduces its value for recording spectra in this region. The other difficulty is that tunnelingmore » through the barrier causes a staggering in the K-rotational structure of isomerizing vibrational levels. The assignment of these levels requires data for K values up to at least 3. Given the rotational selection rule K′ − ℓ{sup ′′} = ± 1, such data must be obtained via excited vibrational levels of the ground state with ℓ{sup ′′} > 0. In this paper, high resolution H-atom resonance-enhanced multiphoton ionization spectra are demonstrated to contain predissociated bands which are almost invisible in LIF spectra, while preliminary data using a hyperthermal pulsed nozzle show that ℓ{sup ′′} = 2 states can be selectively populated in a jet, giving access to K′ = 3 states in IR-UV double resonance.« less

An automated framework for NMR resonance assignment through simultaneous slice picking and spin system forming.

PubMed

Abbas, Ahmed; Guo, Xianrong; Jing, Bing-Yi; Gao, Xin

2014-06-01

Despite significant advances in automated nuclear magnetic resonance-based protein structure determination, the high numbers of false positives and false negatives among the peaks selected by fully automated methods remain a problem. These false positives and negatives impair the performance of resonance assignment methods. One of the main reasons for this problem is that the computational research community often considers peak picking and resonance assignment to be two separate problems, whereas spectroscopists use expert knowledge to pick peaks and assign their resonances at the same time. We propose a novel framework that simultaneously conducts slice picking and spin system forming, an essential step in resonance assignment. Our framework then employs a genetic algorithm, directed by both connectivity information and amino acid typing information from the spin systems, to assign the spin systems to residues. The inputs to our framework can be as few as two commonly used spectra, i.e., CBCA(CO)NH and HNCACB. Different from the existing peak picking and resonance assignment methods that treat peaks as the units, our method is based on 'slices', which are one-dimensional vectors in three-dimensional spectra that correspond to certain ([Formula: see text]) values. Experimental results on both benchmark simulated data sets and four real protein data sets demonstrate that our method significantly outperforms the state-of-the-art methods while using a less number of spectra than those methods. Our method is freely available at http://sfb.kaust.edu.sa/Pages/Software.aspx.

Conformational isomerism of phenolic procyanidins: preferred conformations in organic solvents and water

Treesearch

Tsutomu Hatano; Richard W. Hemingway

1997-01-01

NMR studies of catechin-{4α→8)-epicatechin (I) and catechin-{4α→8)-catechin (2) provided complete assignment of the proton and carbon resonances for both the more extended and compact conformers in the free phenolic form. When 1 is in organic solvents, the more extended rotamer is preferred over the more compact rotamer (10:7), but...

Combining multinuclear high-resolution solid-state MAS NMR and computational methods for resonance assignment of glutathione tripeptide.

PubMed

Sardo, Mariana; Siegel, Renée; Santos, Sérgio M; Rocha, João; Gomes, José R B; Mafra, Luis

2012-06-28

We present a complete set of experimental approaches for the NMR assignment of powdered tripeptide glutathione at natural isotopic abundance, based on J-coupling and dipolar NMR techniques combined with (1)H CRAMPS decoupling. To fully assign the spectra, two-dimensional (2D) high-resolution methods, such as (1)H-(13)C INEPT-HSQC/PRESTO heteronuclear correlations (HETCOR), (1)H-(1)H double-quantum (DQ), and (1)H-(14)N D-HMQC correlation experiments, have been used. To support the interpretation of the experimental data, periodic density functional theory calculations together with the GIPAW approach have been used to calculate the (1)H and (13)C chemical shifts. It is found that the shifts calculated with two popular plane wave codes (CASTEP and Quantum ESPRESSO) are in excellent agreement with the experimental results.

Multiple-step relayed correlation spectroscopy: sequential resonance assignments in oligosaccharides.

PubMed Central

Homans, S W; Dwek, R A; Fernandes, D L; Rademacher, T W

1984-01-01

A general property of the high-resolution proton NMR spectra of oligosaccharides is the appearance of low-field well-resolved resonances corresponding to the anomeric (H1) and H2 protons. The remaining skeletal protons resonate in the region 3-4 ppm, giving rise to an envelope of poorly resolved resonances. Assignments can be made from the H1 and H2 protons to their J-coupled neighbors (H2 and H3) within this main envelope by using 1H-1H correlated spectroscopy. However, the tight coupling (J congruent to delta) between further protons results in poor spectral dispersion with consequent assignment ambiguities. We describe here three-step two-dimensional relayed correlation spectroscopy and show how it can be used to correlate the resolved anomeric (H1) and H2 protons with remote (H4, H5) protons directly through a linear network of couplings using sequential magnetization transfer around the oligosaccharide rings. Resonance assignments are then obtained by inspection of cross-peaks that appear in well-resolved regions of the two-dimensional spectrum. This offers a general solution to the assignment problem in oligosaccharides and, importantly, these assignments will subsequently allow for the three-dimensional solution conformation to be determined by using one-dimensional and two-dimensional nuclear Overhauser experiments. PMID:6593701

Selective excitation enables assignment of proton resonances and (1)H-(1)H distance measurement in ultrafast magic angle spinning solid state NMR spectroscopy.

PubMed

Zhang, Rongchun; Ramamoorthy, Ayyalusamy

2015-07-21

Remarkable developments in ultrafast magic angle spinning (MAS) solid-state NMR spectroscopy enabled proton-based high-resolution multidimensional experiments on solids. To fully utilize the benefits rendered by proton-based ultrafast MAS experiments, assignment of (1)H resonances becomes absolutely necessary. Herein, we propose an approach to identify different proton peaks by using dipolar-coupled heteronuclei such as (13)C or (15)N. In this method, after the initial preparation of proton magnetization and cross-polarization to (13)C nuclei, transverse magnetization of desired (13)C nuclei is selectively prepared by using DANTE (Delays Alternating with Nutations for Tailored Excitation) sequence and then, it is transferred to bonded protons with a short-contact-time cross polarization. Our experimental results demonstrate that protons bonded to specific (13)C atoms can be identified and overlapping proton peaks can also be assigned. In contrast to the regular 2D HETCOR experiment, only a few 1D experiments are required for the complete assignment of peaks in the proton spectrum. Furthermore, the finite-pulse radio frequency driven recoupling sequence could be incorporated right after the selection of specific proton signals to monitor the intensity buildup for other proton signals. This enables the extraction of (1)H-(1)H distances between different pairs of protons. Therefore, we believe that the proposed method will greatly aid in fast assignment of peaks in proton spectra and will be useful in the development of proton-based multi-dimensional solid-state NMR experiments to study atomic-level resolution structure and dynamics of solids.

Novel 2D Triple-Resonance NMR Experiments for Sequential Resonance Assignments of Proteins

NASA Astrophysics Data System (ADS)

Ding, Keyang; Gronenborn, Angela M.

2002-06-01

We present 2D versions of the popular triple resonance HN(CO) CACB, HN(COCA)CACB, HN(CO)CAHA, and HN(COCA) CAHA experiments, commonly used for sequential resonance assignments of proteins. These experiments provide information about correlations between amino proton and nitrogen chemical shifts and the α- and β-carbon and α-proton chemical shifts within and between amino acid residues. Using these 2D spectra, sequential resonance assignments of H N, N, C α, C β, and H α nuclei are easily achieved. The resolution of these spectra is identical to the well-resolved 2D 15N- 1H HSQC and H(NCO)CA spectra, with slightly reduced sensitivity compared to their 3D and 4D versions. These types of spectra are ideally suited for exploitation in automated assignment procedures and thereby constitute a fast and efficient means for NMR structural determination of small and medium-sized proteins in solution in structural genomics programs.

Sequence-specific sup 1 H NMR resonance assignments of Bacillus subtilis HPr: Use of spectra obtained from mutants to resolve spectral overlap

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

Wittekind, M.; Klevit, R.E.; Reizer, J.

1990-08-07

On the basis of an analysis of two-dimensional {sup 1}H NMR spectra, the complete sequence-specific {sup 1}H NMR assignments are presented for the phosphocarrier protein HPr from the Gram-positive bacterium Bacillus subtilis. During the assignment procedure, extensive use was made of spectra obtained from point mutants of HPr in order to resolve spectral overlap and to provide verification of assignments. Regions of regular secondary structure were identified by characteristic patterns of sequential backbone proton NOEs and slowly exchanging amide protons. B subtilis HPr contains four {beta}-strands that form a single antiparallel {beta}-sheet and two well-defined {alpha}-helices. There are two stretchesmore » of extended backbone structure, one of which contains the active site His{sub 15}. The overall fold of the protein is very similar to that of Escherichia coli HPr determined by NMR studies.« less

Resonance assignments for the substrate binding domain of Hsp70 chaperone Ssa1 from Saccharomyces cerevisiae.

PubMed

Hu, Wanhui; Wu, Huiwen; Zhang, Hong; Gong, Weibin; Perrett, Sarah

2015-10-01

Hsp70 chaperone proteins play crucial roles in the cell. Extensive structural and functional studies have been performed for bacterial and mammalian Hsp70s. Ssa1 from Saccharomyces cerevisiae is a member of the Hsp70 family. In vivo and biochemical studies on Ssa1 have revealed that it regulates prion propagation and the cell cycle. However, no structural data has been obtained for Ssa1 up to now. Here we report the almost complete (96 %) (1)H, (13)C, (15)N backbone and side chain NMR assignment of the 18.8 kDa Ssa1 substrate binding domain. The construct includes residues 382-554, which corresponds to the entire substrate binding domain and two following α-helices in homologous structures. The secondary structure predicted from the assigned chemical shifts is consistent with that of homologous Hsp70 substrate binding domains.

Improving the efficiency of branch-and-bound complete-search NMR assignment using the symmetry of molecules and spectra

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

Bernal, Andrés; Patiny, Luc; Castillo, Andrés M.

2015-02-21

Nuclear magnetic resonance (NMR) assignment of small molecules is presented as a typical example of a combinatorial optimization problem in chemical physics. Three strategies that help improve the efficiency of solution search by the branch and bound method are presented: 1. reduction of the size of the solution space by resort to a condensed structure formula, wherein symmetric nuclei are grouped together; 2. partitioning of the solution space based on symmetry, that becomes the basis for an efficient branching procedure; and 3. a criterion of selection of input restrictions that leads to increased gaps between branches and thus faster pruningmore » of non-viable solutions. Although the examples chosen to illustrate this work focus on small-molecule NMR assignment, the results are generic and might help solving other combinatorial optimization problems.« less

Multidimensional oriented solid-state NMR experiments enable the sequential assignment of uniformly 15N labeled integral membrane proteins in magnetically aligned lipid bilayers.

PubMed

Mote, Kaustubh R; Gopinath, T; Traaseth, Nathaniel J; Kitchen, Jason; Gor'kov, Peter L; Brey, William W; Veglia, Gianluigi

2011-11-01

Oriented solid-state NMR is the most direct methodology to obtain the orientation of membrane proteins with respect to the lipid bilayer. The method consists of measuring (1)H-(15)N dipolar couplings (DC) and (15)N anisotropic chemical shifts (CSA) for membrane proteins that are uniformly aligned with respect to the membrane bilayer. A significant advantage of this approach is that tilt and azimuthal (rotational) angles of the protein domains can be directly derived from analytical expression of DC and CSA values, or, alternatively, obtained by refining protein structures using these values as harmonic restraints in simulated annealing calculations. The Achilles' heel of this approach is the lack of suitable experiments for sequential assignment of the amide resonances. In this Article, we present a new pulse sequence that integrates proton driven spin diffusion (PDSD) with sensitivity-enhanced PISEMA in a 3D experiment ([(1)H,(15)N]-SE-PISEMA-PDSD). The incorporation of 2D (15)N/(15)N spin diffusion experiments into this new 3D experiment leads to the complete and unambiguous assignment of the (15)N resonances. The feasibility of this approach is demonstrated for the membrane protein sarcolipin reconstituted in magnetically aligned lipid bicelles. Taken with low electric field probe technology, this approach will propel the determination of sequential assignment as well as structure and topology of larger integral membrane proteins in aligned lipid bilayers. © Springer Science+Business Media B.V. 2011

Stereospecific assignment of the asparagine and glutamine sidechain amide protons in proteins from chemical shift analysis.

PubMed

Harsch, Tobias; Schneider, Philipp; Kieninger, Bärbel; Donaubauer, Harald; Kalbitzer, Hans Robert

2017-02-01

Side chain amide protons of asparagine and glutamine residues in random-coil peptides are characterized by large chemical shift differences and can be stereospecifically assigned on the basis of their chemical shift values only. The bimodal chemical shift distributions stored in the biological magnetic resonance data bank (BMRB) do not allow such an assignment. However, an analysis of the BMRB shows, that a substantial part of all stored stereospecific assignments is not correct. We show here that in most cases stereospecific assignment can also be done for folded proteins using an unbiased artificial chemical shift data base (UACSB). For a separation of the chemical shifts of the two amide resonance lines with differences ≥0.40 ppm for asparagine and differences ≥0.42 ppm for glutamine, the downfield shifted resonance lines can be assigned to H δ21 and H ε21 , respectively, at a confidence level >95%. A classifier derived from UASCB can also be used to correct the BMRB data. The program tool AssignmentChecker implemented in AUREMOL calculates the Bayesian probability for a given stereospecific assignment and automatically corrects the assignments for a given list of chemical shifts.

Alkane Soluble Transition Metal Complexes.

DTIC Science & Technology

1983-10-01

period April 7th 1963 to October 6th 1903 as well an the final report covering the complete period April 15th 1979 to October 6th 1993. The research ...reported In this document has beensmade possible through the support and sponsorship of the US Government through Its Ruropean Research Office. This report...the single triple at 1 0.6 (dowfhleld froma Sill., assigned to the phosphorus resonance Provided further evidence of purity. met),le end a~hy grups

¹⁵N, ¹³C and ¹H resonance assignments and secondary structure determination of a variable heavy domain of a heavy chain antibody.

PubMed

Prosser, Christine E; Waters, Lorna C; Muskett, Frederick W; Veverka, Vaclav; Addis, Philip W; Griffin, Laura M; Baker, Terry S; Lawson, Alastair D G; Wernery, Ulrich; Kinne, Jorg; Henry, Alistair J; Taylor, Richard J; Carr, Mark D

2014-04-01

Heavy chain antibodies differ in structure to conventional antibodies lacking both the light chain and the first heavy chain constant domain (CH1). Characteristics of the antigen-binding variable heavy domain of the heavy chain antibody (VHH) including the smaller size, high solubility and stability make them an attractive alternative to more traditional antibody fragments for detailed NMR-based structural analysis. Here we report essentially complete backbone and side chain (15)N, (13)C and (1)H assignments for a free VHH. Analysis of the backbone chemical shift data obtained indicates that the VHH is comprised predominantly of β-sheets corresponding to nearly 60% of the protein backbone.

Selective excitation enables assignment of proton resonances and {sup 1}H-{sup 1}H distance measurement in ultrafast magic angle spinning solid state NMR spectroscopy

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

Zhang, Rongchun; Ramamoorthy, Ayyalusamy, E-mail: ramamoor@umich.edu

2015-07-21

Remarkable developments in ultrafast magic angle spinning (MAS) solid-state NMR spectroscopy enabled proton-based high-resolution multidimensional experiments on solids. To fully utilize the benefits rendered by proton-based ultrafast MAS experiments, assignment of {sup 1}H resonances becomes absolutely necessary. Herein, we propose an approach to identify different proton peaks by using dipolar-coupled heteronuclei such as {sup 13}C or {sup 15}N. In this method, after the initial preparation of proton magnetization and cross-polarization to {sup 13}C nuclei, transverse magnetization of desired {sup 13}C nuclei is selectively prepared by using DANTE (Delays Alternating with Nutations for Tailored Excitation) sequence and then, it is transferredmore » to bonded protons with a short-contact-time cross polarization. Our experimental results demonstrate that protons bonded to specific {sup 13}C atoms can be identified and overlapping proton peaks can also be assigned. In contrast to the regular 2D HETCOR experiment, only a few 1D experiments are required for the complete assignment of peaks in the proton spectrum. Furthermore, the finite-pulse radio frequency driven recoupling sequence could be incorporated right after the selection of specific proton signals to monitor the intensity buildup for other proton signals. This enables the extraction of {sup 1}H-{sup 1}H distances between different pairs of protons. Therefore, we believe that the proposed method will greatly aid in fast assignment of peaks in proton spectra and will be useful in the development of proton-based multi-dimensional solid-state NMR experiments to study atomic-level resolution structure and dynamics of solids.« less

1H, 13C, and 15N backbone assignment and secondary structure of the receptor-binding domain of vascular endothelial growth factor.

PubMed Central

Fairbrother, W. J.; Champe, M. A.; Christinger, H. W.; Keyt, B. A.; Starovasnik, M. A.

1997-01-01

Nearly complete sequence-specific 1H, 13C, and 15N resonance assignments are reported for the backbone atoms of the receptor-binding domain of vascular endothelial growth factor (VEGF), a 23-kDa homodimeric protein that is a major regulator of both normal and pathological angiogenesis. The assignment strategy relied on the use of seven 3D triple-resonance experiments [HN(CO)CA, HNCA, HNCO, (HCA)CONH, HN(COCA)HA, HN(CA)HA, and CBCA-(CO)NH] and a 3D 15N-TOCSY-HSQC experiment recorded on a 0.5 mM (12 mg/mL) sample at 500 MHz, pH 7.0, 45 degrees C. Under these conditions, 15N relaxation data show that the protein has a rotational correlation time of 15.0 ns. Despite this unusually long correlation time, assignments were obtained for 94 of the 99 residues; 8 residues lack amide 1H and 15N assignments, presumably due to rapid exchange of the amide 1H with solvent under the experimental conditions used. The secondary structure of the protein was deduced from the chemical shift indices of the 1H alpha, 13C alpha, 13C beta, and 13CO nuclei, and from analysis of backbone NOEs observed in a 3D 15N-NOESY-HSQC spectrum. Two helices and a significant amount of beta-sheet structure were identified, in general agreement with the secondary structure found in a recently determined crystal structure of a similar VEGF construct [Muller YA et al., 1997, Proc Natl Acad Sci USA 94:7192-7197]. PMID:9336848

Amino acid selective unlabeling for sequence specific resonance assignments in proteins

PubMed Central

Krishnarjuna, B.; Jaipuria, Garima; Thakur, Anushikha

2010-01-01

Sequence specific resonance assignment constitutes an important step towards high-resolution structure determination of proteins by NMR and is aided by selective identification and assignment of amino acid types. The traditional approach to selective labeling yields only the chemical shifts of the particular amino acid being selected and does not help in establishing a link between adjacent residues along the polypeptide chain, which is important for sequential assignments. An alternative approach is the method of amino acid selective ‘unlabeling’ or reverse labeling, which involves selective unlabeling of specific amino acid types against a uniformly 13C/15N labeled background. Based on this method, we present a novel approach for sequential assignments in proteins. The method involves a new NMR experiment named, {12COi–15Ni+1}-filtered HSQC, which aids in linking the 1HN/15N resonances of the selectively unlabeled residue, i, and its C-terminal neighbor, i + 1, in HN-detected double and triple resonance spectra. This leads to the assignment of a tri-peptide segment from the knowledge of the amino acid types of residues: i − 1, i and i + 1, thereby speeding up the sequential assignment process. The method has the advantage of being relatively inexpensive, applicable to 2H labeled protein and can be coupled with cell-free synthesis and/or automated assignment approaches. A detailed survey involving unlabeling of different amino acid types individually or in pairs reveals that the proposed approach is also robust to misincorporation of 14N at undesired sites. Taken together, this study represents the first application of selective unlabeling for sequence specific resonance assignments and opens up new avenues to using this methodology in protein structural studies. Electronic supplementary material The online version of this article (doi:10.1007/s10858-010-9459-z) contains supplementary material, which is available to authorized users. PMID:21153044

Resonances above the proton threshold in 26Si

DOE PAGES

Chipps, Kelly A.

2016-03-06

26Al remains an intriguing target for observational gamma-ray astronomy, thanks to its characteristic decay. The 25Al(p, )26Si reaction is part of a chain that bypasses the production of the observable 26Alg in favor of the isomeric state; its rate at novae temperatures is dominated by a resonance around 400 keV, the precise location and J assignment of which has been hotly debated. Considerable confusion in this regard has arisen from the use of outdated excitation energies and masses. Here, a reanalysis of previous work is completed to first, elucidate the confusion regarding the level structure just above the proton threshold,more » and second, provide focus to future studies.« less

H6+ in irradiated solid para-hydrogen and its decay dynamics: reinvestigation of quartet electron paramagnetic resonance lines assigned to H2-.

PubMed

Kumada, Takayuki; Tachikawa, Hiroto; Takayanagi, Toshiyuki

2005-03-07

The quartet electron paramagnetic resonance (EPR) lines observed in gamma- and X-ray irradiated solid para-H2, which have previously been assigned to H2-, are reinvestigated. We have reassigned the quartet lines to H6 rather than H2- mainly due to comparison of experimentally obtained EPR parameters to theoretical results. Based on the new assignment, trapping site, rotation, ortho-para conversion, quantum diffusion and isotope effect of H+ have been reinterpreted by the precise reanalysis as follows. The H6+ ion is composed of the collinearly aligned H2+ core at the center and two H2 rotors at both ends, occupies a single substitutional site, and has a precession motion around a crystalline axis with the angle of approximately 57 degrees. The ortho-para conversion of H2+ core of H6+ is completed within the time-scale of hours, whereas ortho-H2 molecules near H6+ convert much faster. H6+ diffuses quantum mechanically by the repetition of H6+ + H2 --> H2 + H6+ reaction. The diffusion terminates by the reaction, H6(+) + HD --> H5D(+) + H2, with a HD impurity contained in the para-H2 sample at natural abundance. Finally, we will propose a possible reason why H6+ is produced instead of H3+ in the irradiated solid H2.

1H, 15N, 13C resonance assignment of folded and 8 M urea-denatured state of SUMO from Drosophila melanogaster.

PubMed

Kumar, Dinesh; Kumar, Ashutosh; Misra, Jyoti Ranjan; Chugh, Jeetender; Sharma, Shilpy; Hosur, Ramakrishna V

2008-06-01

SUMO, an important post-translational modifier of variety of substrate proteins, regulates different cellular functions. Here, we report the NMR resonance assignment of the folded and 8 M urea-denatured state of SUMO from Drosophila melanogaster (dsmt3).

Sequential /sup 1/H NMR assignments and secondary structure of hen egg white lysozyme in solution

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

Redfield, C.; Dobson, C.M.

Assignments of /sup 1/H NMR resonances of 121 of the 129 residues of hen egg white lysozyme have been obtained by sequence-specific methods. Spin systems were identified with phase-sensitive two-dimensional (2-D) correlated spectroscopy and single and double relayed coherence transfer spectroscopy. For key types of amino acid residues, particularly alanine, threonine, valine, and glycine, complete spin systems were identified. For other residues a less complete definition of the spin system was found to be adequate for the purpose of sequential assignment. Sequence-specific assignments were achieved by phase-sensitive 2-D nuclear Overhauser enhancement spectroscopy (NOESY). Exploitation of the wide range of hydrogenmore » exchange rates found in lysozyme was a useful approach to overcoming the problem of spectral overlap. The sequential assignment was built up from 21 peptide segments ranging in length from 2 to 13 residues. The NOESY spectra were also used to provide information about the secondary structure of the protein in solution. Three helical regions and two regions of ..beta..-sheet were identified from the NOESY data; these regions are identical with those found in the X-ray structure of hen lysozyme. Slowly exchanging amides are generally correlated with hydrogen bonding identified in the X-ray structure; a number of exceptions to this general trend were, however, found. The results presented in this paper indicate that highly detailed information can be obtained from 2-D NMR spectra of a protein that is significantly larger than those studies previously.« less

Fast and accurate resonance assignment of small-to-large proteins by combining automated and manual approaches.

PubMed

Niklasson, Markus; Ahlner, Alexandra; Andresen, Cecilia; Marsh, Joseph A; Lundström, Patrik

2015-01-01

The process of resonance assignment is fundamental to most NMR studies of protein structure and dynamics. Unfortunately, the manual assignment of residues is tedious and time-consuming, and can represent a significant bottleneck for further characterization. Furthermore, while automated approaches have been developed, they are often limited in their accuracy, particularly for larger proteins. Here, we address this by introducing the software COMPASS, which, by combining automated resonance assignment with manual intervention, is able to achieve accuracy approaching that from manual assignments at greatly accelerated speeds. Moreover, by including the option to compensate for isotope shift effects in deuterated proteins, COMPASS is far more accurate for larger proteins than existing automated methods. COMPASS is an open-source project licensed under GNU General Public License and is available for download from http://www.liu.se/forskning/foass/tidigare-foass/patrik-lundstrom/software?l=en. Source code and binaries for Linux, Mac OS X and Microsoft Windows are available.

Fast and Accurate Resonance Assignment of Small-to-Large Proteins by Combining Automated and Manual Approaches

PubMed Central

Niklasson, Markus; Ahlner, Alexandra; Andresen, Cecilia; Marsh, Joseph A.; Lundström, Patrik

2015-01-01

The process of resonance assignment is fundamental to most NMR studies of protein structure and dynamics. Unfortunately, the manual assignment of residues is tedious and time-consuming, and can represent a significant bottleneck for further characterization. Furthermore, while automated approaches have been developed, they are often limited in their accuracy, particularly for larger proteins. Here, we address this by introducing the software COMPASS, which, by combining automated resonance assignment with manual intervention, is able to achieve accuracy approaching that from manual assignments at greatly accelerated speeds. Moreover, by including the option to compensate for isotope shift effects in deuterated proteins, COMPASS is far more accurate for larger proteins than existing automated methods. COMPASS is an open-source project licensed under GNU General Public License and is available for download from http://www.liu.se/forskning/foass/tidigare-foass/patrik-lundstrom/software?l=en. Source code and binaries for Linux, Mac OS X and Microsoft Windows are available. PMID:25569628

Proton nuclear magnetic resonance studies on the variant-3 neurotoxin from Centruroides sculpturatus Ewing: Sequential assignment of resonances

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

Nettesheim, D.G.; Klevit, R.E.; Drobny, G.

1989-02-21

The authors report the sequential assignment of resonances to specific residues in the proton nuclear magnetic resonance spectrum of the variant-3 neurotoxin from the scorpion Centruroides sculpturatus Ewing (range southwestern U.S.A.). A combination of two-dimensional NMR experiments such as 2D-COSY, 2D-NOESY, and single- and double-RELAY coherence transfer spectroscopy has been employed on samples of the protein dissolved in D{sub 2}O and in H{sub 2}O for assignment purposes. These studies provide a basis for the determination of the solution-phase conformation of this protein and for undertaking detailed structure-function studies of these neurotoxins that modulate the flow of sodium current by bindingmore » to the sodium channels of excitable membranes.« less

NMR assignment of a PDZ domain in complex with a HPV51 E6 derived N-terminally pyroglutamic acid modified peptide.

PubMed

Mischo, André; Ohlenschläger, Oliver; Ramachandran, Ramadurai; Görlach, Matthias

2013-04-01

The resonance assignment of an amino-terminal pyroglutamic acid containing peptide derived from the E6 protein of human papillomavirus (HPV) type 51 in complex with PDZ domain 2 of hDlg/SAP-97 is reported. The assignments include (1)H, (13)C and (15)N resonances for the protein and peptide in the complex and all of the peptide's pyroglutamic acid nuclei.

On the problem of resonance assignments in solid state NMR of uniformly 15N, 13C-labeled proteins

NASA Astrophysics Data System (ADS)

Tycko, Robert

2015-04-01

Determination of accurate resonance assignments from multidimensional chemical shift correlation spectra is one of the major problems in biomolecular solid state NMR, particularly for relative large proteins with less-than-ideal NMR linewidths. This article investigates the difficulty of resonance assignment, using a computational Monte Carlo/simulated annealing (MCSA) algorithm to search for assignments from artificial three-dimensional spectra that are constructed from the reported isotropic 15N and 13C chemical shifts of two proteins whose structures have been determined by solution NMR methods. The results demonstrate how assignment simulations can provide new insights into factors that affect the assignment process, which can then help guide the design of experimental strategies. Specifically, simulations are performed for the catalytic domain of SrtC (147 residues, primarily β-sheet secondary structure) and the N-terminal domain of MLKL (166 residues, primarily α-helical secondary structure). Assuming unambiguous residue-type assignments and four ideal three-dimensional data sets (NCACX, NCOCX, CONCA, and CANCA), uncertainties in chemical shifts must be less than 0.4 ppm for assignments for SrtC to be unique, and less than 0.2 ppm for MLKL. Eliminating CANCA data has no significant effect, but additionally eliminating CONCA data leads to more stringent requirements for chemical shift precision. Introducing moderate ambiguities in residue-type assignments does not have a significant effect.

NMR conformational properties of an Anthrax Lethal Factor domain studied by multiple amino acid-selective labeling

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

Vourtsis, Dionysios J.; Chasapis, Christos T.; Pairas, George

2014-07-18

Highlights: • A polypeptide, N-ALF{sub 233}, was overexpressed in E. coli and successfully isolated. • We produced {sup 2}H/{sup 15}N/{sup 13}C labeled protein samples. • Amino acid selective approaches were applied. • We acquired several heteronuclear NMR spectra, to complete the backbone assignment. • Prediction of the secondary structure was performed. - Abstract: NMR-based structural biology urgently needs cost- and time-effective methods to assist both in the process of acquiring high-resolution NMR spectra and their subsequent analysis. Especially for bigger proteins (>20 kDa) selective labeling is a frequently used means of sequence-specific assignment. In this work we present the successfulmore » overexpression of a polypeptide of 233 residues, corresponding to the structured part of the N-terminal domain of Anthrax Lethal Factor, using Escherichia coli expression system. The polypeptide was subsequently isolated in pure, soluble form and analyzed structurally by solution NMR spectroscopy. Due to the non-satisfying quality and resolution of the spectra of this 27 kDa protein, an almost complete backbone assignment became feasible only by the combination of uniform and novel amino acid-selective labeling schemes. Moreover, amino acid-type selective triple-resonance NMR experiments proved to be very helpful.« less

Effortless assignment with 4D covariance sequential correlation maps.

PubMed

Harden, Bradley J; Mishra, Subrata H; Frueh, Dominique P

2015-11-01

Traditional Nuclear Magnetic Resonance (NMR) assignment procedures for proteins rely on preliminary peak-picking to identify and label NMR signals. However, such an approach has severe limitations when signals are erroneously labeled or completely neglected. The consequences are especially grave for proteins with substantial peak overlap, and mistakes can often thwart entire projects. To overcome these limitations, we previously introduced an assignment technique that bypasses traditional pick peaking altogether. Covariance Sequential Correlation Maps (COSCOMs) transform the indirect connectivity information provided by multiple 3D backbone spectra into direct (H, N) to (H, N) correlations. Here, we present an updated method that utilizes a single four-dimensional spectrum rather than a suite of three-dimensional spectra. We demonstrate the advantages of 4D-COSCOMs relative to their 3D counterparts. We introduce improvements accelerating their calculation. We discuss practical considerations affecting their quality. And finally we showcase their utility in the context of a 52 kDa cyclization domain from a non-ribosomal peptide synthetase. Copyright © 2015 Elsevier Inc. All rights reserved.

Effortless assignment with 4D covariance sequential correlation maps

NASA Astrophysics Data System (ADS)

Harden, Bradley J.; Mishra, Subrata H.; Frueh, Dominique P.

2015-11-01

Traditional Nuclear Magnetic Resonance (NMR) assignment procedures for proteins rely on preliminary peak-picking to identify and label NMR signals. However, such an approach has severe limitations when signals are erroneously labeled or completely neglected. The consequences are especially grave for proteins with substantial peak overlap, and mistakes can often thwart entire projects. To overcome these limitations, we previously introduced an assignment technique that bypasses traditional pick peaking altogether. Covariance Sequential Correlation Maps (COSCOMs) transform the indirect connectivity information provided by multiple 3D backbone spectra into direct (H, N) to (H, N) correlations. Here, we present an updated method that utilizes a single four-dimensional spectrum rather than a suite of three-dimensional spectra. We demonstrate the advantages of 4D-COSCOMs relative to their 3D counterparts. We introduce improvements accelerating their calculation. We discuss practical considerations affecting their quality. And finally we showcase their utility in the context of a 52 kDa cyclization domain from a non-ribosomal peptide synthetase.

Neutron Resonance Spin Determination Using Multi-Segmented Detector DANCE

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

Baramsai, B.; Mitchell, G. E.; Chyzh, A.

2011-06-01

A sensitive method to determine the spin of neutron resonances is introduced based on the statistical pattern recognition technique. The new method was used to assign the spins of s-wave resonances in {sup 155}Gd. The experimental neutron capture data for these nuclei were measured with the DANCE (Detector for Advanced Neutron Capture Experiment) calorimeter at the Los Alamos Neutron Science Center. The highly segmented calorimeter provided detailed multiplicity distributions of the capture {gamma}-rays. Using this information, the spins of the neutron capture resonances were determined. With these new spin assignments, level spacings are determined separately for s-wave resonances with J{supmore » {pi}} = 1{sup -} and 2{sup -}.« less

"Ask Ernö": a self-learning tool for assignment and prediction of nuclear magnetic resonance spectra.

PubMed

Castillo, Andrés M; Bernal, Andrés; Dieden, Reiner; Patiny, Luc; Wist, Julien

2016-01-01

We present "Ask Ernö", a self-learning system for the automatic analysis of NMR spectra, consisting of integrated chemical shift assignment and prediction tools. The output of the automatic assignment component initializes and improves a database of assigned protons that is used by the chemical shift predictor. In turn, the predictions provided by the latter facilitate improvement of the assignment process. Iteration on these steps allows Ask Ernö to improve its ability to assign and predict spectra without any prior knowledge or assistance from human experts. This concept was tested by training such a system with a dataset of 2341 molecules and their (1)H-NMR spectra, and evaluating the accuracy of chemical shift predictions on a test set of 298 partially assigned molecules (2007 assigned protons). After 10 iterations, Ask Ernö was able to decrease its prediction error by 17 %, reaching an average error of 0.265 ppm. Over 60 % of the test chemical shifts were predicted within 0.2 ppm, while only 5 % still presented a prediction error of more than 1 ppm. Ask Ernö introduces an innovative approach to automatic NMR analysis that constantly learns and improves when provided with new data. Furthermore, it completely avoids the need for manually assigned spectra. This system has the potential to be turned into a fully autonomous tool able to compete with the best alternatives currently available.Graphical abstractSelf-learning loop. Any progress in the prediction (forward problem) will improve the assignment ability (reverse problem) and vice versa.

Backbone resonance assignments of the PRYSPRY domain of TRIM25.

PubMed

Kong, Chen; Penumutchu, Srinivasa R; Hung, Kuo-Wei; Huang, Huiying; Lin, Tianwei; Yu, Chin

2015-10-01

TRIM25 is a member of the tripartite motif (TRIM) family and has been implicated in the regulation of innate immune signaling via the RIG-I (retinoic acid-inducible gene-I) pathway for antiviral defense. As the essential first step towards the structural and functional characterization of the TRIM25/RIG-I interaction, the backbone resonance of the PRYSPRY domain of TRIM25 is assigned here based on triple-resonance experiments using uniformly [(2)H, (13)C, (15)N]-labeled protein.

An Investigation of the Partial-Assignment Completion Effect on Students' Assignment Choice Behavior

ERIC Educational Resources Information Center

Hawthorn-Embree, Meredith L.; Skinner, Christopher H.; Parkhurst, John; Conley, Elisha

2011-01-01

This study was designed to investigate the partial assignment completion effect. Seventh-grade students were given a math assignment. After working for 5 min, they were interrupted and their partially completed assignments were collected. About 20 min later, students were given their partially completed assignment and a new, control assignment…

Franck-Condon fingerprinting of vibration-tunneling spectra.

PubMed

Berrios, Eduardo; Sundaradevan, Praveen; Gruebele, Martin

2013-08-15

We introduce Franck-Condon fingerprinting as a method for assigning complex vibration-tunneling spectra. The B̃ state of thiophosgene (SCCl2) serves as our prototype. Despite several attempts, assignment of its excitation spectrum has proved difficult because of near-degenerate vibrational frequencies, Fermi resonance between the C-Cl stretching mode and the Cl-C-Cl bending mode, and large tunneling splittings due to the out-of-plane umbrella mode. Hence, the spectrum has never been fitted to an effective Hamiltonian. Our assignment approach replaces precise frequency information with intensity information, eliminating the need for double resonance spectroscopy or combination differences, neither of which have yielded a full assignment thus far. The dispersed fluorescence spectrum of each unknown vibration-tunneling state images its character onto known vibrational progressions in the ground state. By using this Franck-Condon fingerprint, we were able to determine the predominant character of several vibration-tunneling states and assign them; in other cases, the fingerprinting revealed that the states are strongly mixed and cannot be characterized with a simple normal mode assignment. The assigned transitions from vibration-tunneling wave functions that were not too strongly mixed could be fitted within measurement uncertainty by an effective vibration-tunneling Hamiltonian. A fit of all observed vibration-tunneling states will require a full resonance-tunneling Hamiltonian.

Raman spectra of ruthenium and tantalum trimers in argon matrices

NASA Astrophysics Data System (ADS)

Fang, Li; Shen, Xiaole; Chen, Xiaoyu; Lombardi, John R.

2000-12-01

The resonance Raman spectra of ruthenium trimers (Ru 3) in argon matrices have been obtained. Three resonance Raman transitions were observed between 570 and 590 nm. Two of them (303.4 and 603.7 cm -1) are assigned to the totally symmetric vibrational progression, giving k e=1.86 mdyne/ Å. The line at 581.5 cm-1 is assigned as the origin of a low-lying electronic state. We also report on the observation of a resonance Raman spectrum of tantalum trimers (Ta 3). Observed lines include 251.2 and 501.9 cm-1 which we assign to the fundamental and the first overtone of the symmetric stretch in Ta 3. This gives k e=2.25 mdyne/ Å.

Assignment Choice, Effort, and Assignment Completion: Does Work Ethic Predict Those Who Choose Higher-Effort Assignments?

ERIC Educational Resources Information Center

Parkhurst, John T.; Fleisher, Matthew S.; Skinner, Christopher H.; Woehr, David J.; Hawthorn-Embree, Meredith L.

2011-01-01

After completing the Multidimensional Work-Ethic Profile (MWEP), 98 college students were given a 20-problem math computation assignment and instructed to stop working on the assignment after completing 10 problems. Next, they were allowed to choose to finish either the partially completed assignment that had 10 problems remaining or a new…

Replicating and Extending Research on the Partial Assignment Completion Effect: Is Sunk Cost Related to Partial Assignment Completion Strength?

ERIC Educational Resources Information Center

Hawthorn-Embree, Meredith L.; Taylor, Emily P.; Skinner, Christopher H.; Parkhurst, John; Nalls, Meagan L.

2014-01-01

After students acquire a skill, mastery often requires them to choose to engage in assigned academic activities (e.g., independent seatwork, and homework). Although students may be more likely to choose to work on partially completed assignments than on new assignments, the partial assignment completion (PAC) effect may not be very powerful. The…

Sequence-specific 1H-NMR assignments for the aromatic region of several biologically active, monomeric insulins including native human insulin.

PubMed

Roy, M; Lee, R W; Kaarsholm, N C; Thøgersen, H; Brange, J; Dunn, M F

1990-06-12

The aromatic region of the 1H-FT-NMR spectrum of the biologically fully-potent, monomeric human insulin mutant, B9 Ser----Asp, B27 Thr----Glu has been investigated in D2O. At 1 to 5 mM concentrations, this mutant insulin is monomeric above pH 7.5. Coupling and amino acid classification of all aromatic signals is established via a combination of homonuclear one- and two-dimensional methods, including COSY, multiple quantum filters, selective spin decoupling and pH titrations. By comparisons with other insulin mutants and with chemically modified native insulins, all resonances in the aromatic region are given sequence-specific assignments without any reliance on the various crystal structures reported for insulin. These comparisons also give the sequence-specific assignments of most of the aromatic resonances of the mutant insulins B16 Tyr----Glu, B27 Thr----Glu and B25 Phe----Asp and the chemically modified species des-(B23-B30) insulin and monoiodo-Tyr A14 insulin. Chemical dispersion of the assigned resonances, ring current perturbations and comparisons at high pH have made possible the assignment of the aromatic resonances of human insulin, and these studies indicate that the major structural features of the human insulin monomer (including those critical to biological function) are also present in the monomeric mutant.

Advances in stable isotope assisted labeling strategies with information science.

PubMed

Kigawa, Takanori

2017-08-15

Stable-isotope (SI) labeling of proteins is an essential technique to investigate their structures, interactions or dynamics by nuclear magnetic resonance (NMR) spectroscopy. The assignment of the main-chain signals, which is the fundamental first step in these analyses, is usually achieved by a sequential assignment method based on triple resonance experiments. Independently of the triple resonance experiment-based sequential assignment, amino acid-selective SI labeling is beneficial for discriminating the amino acid type of each signal; therefore, it is especially useful for the signal assignment of difficult targets. Various combinatorial selective labeling schemes have been developed as more sophisticated labeling strategies. In these strategies, amino acids are represented by combinations of SI labeled samples, rather than simply assigning one amino acid to one SI labeled sample as in the case of conventional amino acid-selective labeling. These strategies have proven to be useful for NMR analyses of difficult proteins, such as those in large complex systems, in living cells, attached or integrated into membranes, or with poor solubility. In this review, recent advances in stable isotope assisted labeling strategies will be discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Driscoll, P.C.; Clore, G.M.; Beress, L.

The sequential resonance assignment of the {sup 1}H NMR spectrum of the antihypertensive and antiviral protein BDS-I from the sea anemone Anemonia sulcata is presented. This is carried out with two-dimensional NMR techniques to identify through-bond and through-space (< 5{angstrom}) connectivities. Added spectral complexity arises from the fact that the sample is an approximately 1:1 mixture of two BDS-I isoproteins, (Leu-18)-BDS-I and (Phe-18)-BDS-I. Complete assignments, however, are obtained, largely due to the increased resolution and sensitivity afforded at 600 MHz. In addition, the stereospecific assignment of a large number of {beta}-methylene protons is achieved from an analysis of the patternmore » of {sup 3}J{sub {alpha}{beta}} coupling constants and the relative magnitudes of intraresidue NOEs involving the NH, C{sup {alpha}}H, and C{sup {beta}}H protons. Regular secondary structure elements are deduced from a qualitative interpretation of the nuclear Overhauser enhancement, {sup 3}J{sub HN{alpha}} coupling constant, and amide NH exchange data. A triple-stranded antiparallel {beta}-sheet is found to be related to that found in partially homologous sea anemone polypeptide toxins.« less

Image Guided Focal Therapy for Magnetic Resonance Imaging Visible Prostate Cancer: Defining a 3-Dimensional Treatment Margin Based on Magnetic Resonance Imaging Histology Co-Registration Analysis.

PubMed

Le Nobin, Julien; Rosenkrantz, Andrew B; Villers, Arnauld; Orczyk, Clément; Deng, Fang-Ming; Melamed, Jonathan; Mikheev, Artem; Rusinek, Henry; Taneja, Samir S

2015-08-01

We compared prostate tumor boundaries on magnetic resonance imaging and radical prostatectomy histological assessment using detailed software assisted co-registration to define an optimal treatment margin for achieving complete tumor destruction during image guided focal ablation. Included in study were 33 patients who underwent 3 Tesla magnetic resonance imaging before radical prostatectomy. A radiologist traced lesion borders on magnetic resonance imaging and assigned a suspicion score of 2 to 5. Three-dimensional reconstructions were created from high resolution digitalized slides of radical prostatectomy specimens and co-registered to imaging using advanced software. Tumors were compared between histology and imaging by the Hausdorff distance and stratified by the magnetic resonance imaging suspicion score, Gleason score and lesion diameter. Cylindrical volume estimates of treatment effects were used to define the optimal treatment margin. Three-dimensional software based registration with magnetic resonance imaging was done in 46 histologically confirmed cancers. Imaging underestimated tumor size with a maximal discrepancy between imaging and histological boundaries for a given tumor of an average ± SD of 1.99 ± 3.1 mm, representing 18.5% of the diameter on imaging. Boundary underestimation was larger for lesions with an imaging suspicion score 4 or greater (mean 3.49 ± 2.1 mm, p <0.001) and a Gleason score of 7 or greater (mean 2.48 ± 2.8 mm, p = 0.035). A simulated cylindrical treatment volume based on the imaging boundary missed an average 14.8% of tumor volume compared to that based on the histological boundary. A simulated treatment volume based on a 9 mm treatment margin achieved complete histological tumor destruction in 100% of patients. Magnetic resonance imaging underestimates histologically determined tumor boundaries, especially for lesions with a high imaging suspicion score and a high Gleason score. A 9 mm treatment margin around a lesion visible on magnetic resonance imaging would consistently ensure treatment of the entire histological tumor volume during focal ablative therapy. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

NMR assignments of the N-terminal domain of Nephila clavipes spidroin 1

PubMed Central

Parnham, Stuart; Gaines, William A.; Duggan, Brendan M.; Marcotte, William R.

2011-01-01

The building blocks of spider dragline silk are two fibrous proteins secreted from the major ampullate gland named spidroins 1 and 2 (MaSp1, MaSp2). These proteins consist of a large central domain composed of approximately 100 tandem copies of a 35–40 amino acid repeat sequence. Non-repetitive N and C-terminal domains, of which the C-terminal domain has been implicated to transition from soluble and insoluble states during spinning, flank the repetitive core. The N-terminal domain until recently has been largely unknown due to difficulties in cloning and expression. Here, we report nearly complete assignment for all 1H, 13C, and 15N resonances in the 14 kDa N-terminal domain of major ampullate spidroin 1 (MaSp1-N) of the golden orb-web spider Nephila clavipes. PMID:21152998

Reassigning the CaH+ 11Σ → 21Σ vibronic transition with CaD+

NASA Astrophysics Data System (ADS)

Condoluci, J.; Janardan, S.; Calvin, A. T.; Rugango, R.; Shu, G.; Sherrill, C. D.; Brown, K. R.

2017-12-01

We observe vibronic transitions in CaD+ between the 11Σ and 21Σ electronic states by resonance enhanced multiphoton photodissociation spectroscopy in a Coulomb crystal. The vibronic transitions are compared with previous measurements on CaH+. The result is a revised assignment of the CaH+ vibronic levels and a disagreement with multi-state-complete-active-space second-order perturbation theory theoretical calculations by approximately 700 cm-1. Updated high-level coupled-cluster calculations that include core-valence correlations reduce the disagreement between theory and experiment to 300 cm-1.

Practical aspects of NMR signal assignment in larger and challenging proteins

PubMed Central

Frueh, Dominique P.

2014-01-01

NMR has matured into a technique routinely employed for studying proteins in near physiological conditions. However, applications to larger proteins are impeded by the complexity of the various correlation maps necessary to assign NMR signals. This article reviews the data analysis techniques traditionally employed for resonance assignment and describes alternative protocols necessary for overcoming challenges in large protein spectra. In particular, simultaneous analysis of multiple spectra may help overcome ambiguities or may reveal correlations in an indirect manner. Similarly, visualization of orthogonal planes in a multidimensional spectrum can provide alternative assignment procedures. We describe examples of such strategies for assignment of backbone, methyl, and nOe resonances. We describe experimental aspects of data acquisition for the related experiments and provide guidelines for preliminary studies. Focus is placed on large folded monomeric proteins and examples are provided for 37, 48, 53, and 81 kDa proteins. PMID:24534088

sup 1 H assignments and secondary structure determination of the soybean trypsin/chymotrypsin Bowman-Birk inhibitor

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

Werner, M.H.; Wemmer, D.E.

1991-04-09

The {sup 1}H resonance assignments and secondary structure of the trypsin/chymotrypsin Bowman-Birk inhibitor from soybeans were determined by nuclear magnetic resonance spectroscopy (NMR) at 600 MHz in an 18% acetonitrile-d{sub 3}/aqueous cosolvent. Resonances from 69 to 71 amino acids were assigned sequence specifically. Residues Q11-T15 form an antiparallel {beta}-sheet with residues Q21-S25 in the tryptic inhibitory domain and an analogous region of antiparallel sheet forms between residues S38-A42 and Q48-V52 in the chymotryptic inhibitory domain. The inhibitory sites of each fragment (K16-S17 for trypsin, L43-S44 for chymotrypsin) are each part of a type VI like turn at one end ofmore » their respective region of the antiparallel {beta}-sheet. These structural elements are compared to those found in other Bowman-Birk inhibitors.« less

Longitudinal Evaluation of the Importance of Homework Assignment Completion for the Academic Performance of Middle School Students with ADHD

PubMed Central

Langberg, Joshua M.; Dvorsky, Melissa R.; Molitor, Stephen J.; Bourchtein, Elizaveta; Eddy, Laura D.; Smith, Zoe; Schultz, Brandon K.; Evans, Steven W.

2016-01-01

The primary goal of this study was to longitudinally evaluate the homework assignment completion patterns of middle school age adolescents with ADHD, their associations with academic performance, and malleable predictors of homework assignment completion. Analyses were conducted on a sample of 104 middle school students comprehensively diagnosed with ADHD and followed for 18 months. Multiple teachers for each student provided information about the percentage of homework assignments turned in at five separate timepoints and school grades were collected quarterly. Results showed that agreement between teachers with respect to students’ assignment completion was high, with an intraclass correlation of .879 at baseline. Students with ADHD were turning in an average of 12% fewer assignments each academic quarter in comparison to teacher-reported classroom averages. Regression analyses revealed a robust association between the percentage of assignments turned in at baseline and school grades 18 months later, even after controlling for baseline grades, achievement (reading and math), intelligence, family income, and race. Cross-lag analyses demonstrated that the association between assignment completion and grades was reciprocal, with assignment completion negatively impacting grades and low grades in turn being associated with decreased future homework completion. Parent ratings of homework materials management abilities at baseline significantly predicted the percentage of assignments turned in as reported by teachers 18 months later. These findings demonstrate that homework assignment completion problems are persistent across time and an important intervention target for adolescents with ADHD. PMID:26931065

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

Metz, G.; Siebert, F.; Engelhard, M.

Solid state {sup 13}C nuclear magnetic resonance measurements of bacteriorhodopsin labeled with (4-{sup 13}C)Asp show that resonances of single amino acids can be resolved. In order to assign and characterize the resonances of specific Asp residues, three different approaches were used. (1) Determination of the chemical shift anisotropy from side-band intensities provides information about the protonation state of Asp residues; (2) relaxation studies and T{sub 1} filtering allow one to discriminate between resonances with different mobility; (3) a comparison of the spectra of light- and dark-adapted bacteriorhodopsin provides evidence for resonances from aspartic acid residues in close neighborhood of themore » chromophore. In agreement with other investigations, four resonances are assigned to internal residues. Two of them are protonated in the ground state up to pH 10 (Asp{sub 96} and Asp{sub 115}). All other detected resonance, including Asp{sub 85} and Asp{sub 212}, are due to deprotonated aspartic acid. Two lines due to the two internal deprotonated groups change upon dark and light adaptation, whereas the protonated Asp residues are unaffected.« less

Longitudinal evaluation of the importance of homework assignment completion for the academic performance of middle school students with ADHD.

PubMed

Langberg, Joshua M; Dvorsky, Melissa R; Molitor, Stephen J; Bourchtein, Elizaveta; Eddy, Laura D; Smith, Zoe; Schultz, Brandon K; Evans, Steven W

2016-04-01

The primary goal of this study was to longitudinally evaluate the homework assignment completion patterns of middle school age adolescents with ADHD, their associations with academic performance, and malleable predictors of homework assignment completion. Analyses were conducted on a sample of 104 middle school students comprehensively diagnosed with ADHD and followed for 18 months. Multiple teachers for each student provided information about the percentage of homework assignments turned in at five separate time points and school grades were collected quarterly. Results showed that agreement between teachers with respect to students assignment completion was high, with an intraclass correlation of .879 at baseline. Students with ADHD were turning in an average of 12% fewer assignments each academic quarter in comparison to teacher-reported classroom averages. Regression analyses revealed a robust association between the percentage of assignments turned in at baseline and school grades 18 months later, even after controlling for baseline grades, achievement (reading and math), intelligence, family income, and race. Cross-lag analyses demonstrated that the association between assignment completion and grades was reciprocal, with assignment completion negatively impacting grades and low grades in turn being associated with decreased future homework completion. Parent ratings of homework materials management abilities at baseline significantly predicted the percentage of assignments turned in as reported by teachers 18 months later. These findings demonstrate that homework assignment completion problems are persistent across time and an important intervention target for adolescents with ADHD. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Practice Makes Progress? Homework Assignments and Outcome in Treatment of Cocaine Dependence

PubMed Central

Carroll, Kathleen M.; Nich, Charla; Ball, Samuel A.

2008-01-01

The relationship between treatment outcome and the extent to which participants completed homework assignments was evaluated among 60 cocaine-dependent individuals assigned to cognitive–behavioral therapy (CBT). Homework was assigned in 72% of all sessions and initiated by participants in 48% of the sessions in which it was assigned. Completion of homework was unrelated to participants' baseline characteristics and several indicators of treatment compliance. Participants who completed more homework assignments demonstrated significantly greater increases in the quantity and quality of their coping skills and used significantly less cocaine during treatment and through a 1-year follow-up. These data suggest that the extent to which participants are willing to complete extrasession assignments may be an important mediator of response to CBT. PMID:16173864

Reliable resonance assignments of selected residues of proteins with known structure based on empirical NMR chemical shift prediction

NASA Astrophysics Data System (ADS)

Li, Da-Wei; Meng, Dan; Brüschweiler, Rafael

2015-05-01

A robust NMR resonance assignment method is introduced for proteins whose 3D structure has previously been determined by X-ray crystallography. The goal of the method is to obtain a subset of correct assignments from a parsimonious set of 3D NMR experiments of 15N, 13C labeled proteins. Chemical shifts of sequential residue pairs are predicted from static protein structures using PPM_One, which are then compared with the corresponding experimental shifts. Globally optimized weighted matching identifies the assignments that are robust with respect to small changes in NMR cross-peak positions. The method, termed PASSPORT, is demonstrated for 4 proteins with 100-250 amino acids using 3D NHCA and a 3D CBCA(CO)NH experiments as input producing correct assignments with high reliability for 22% of the residues. The method, which works best for Gly, Ala, Ser, and Thr residues, provides assignments that serve as anchor points for additional assignments by both manual and semi-automated methods or they can be directly used for further studies, e.g. on ligand binding, protein dynamics, or post-translational modification, such as phosphorylation.

Reliable Resonance Assignments of Selected Residues of Proteins with Known Structure Based on Empirical NMR Chemical Shift Prediction

PubMed Central

Li, Da-Wei; Meng, Dan; Brüschweiler, Rafael

2015-01-01

A robust NMR resonance assignment method is introduced for proteins whose 3D structure has previously been determined by X-ray crystallography. The goal of the method is to obtain a subset of correct assignments from a parsimonious set of 3D NMR experiments of 15N, 13C labeled proteins. Chemical shifts of sequential residue pairs are predicted from static protein structures using PPM_One, which are then compared with the corresponding experimental shifts. Globally optimized weighted matching identifies the assignments that are robust with respect to small changes in NMR cross-peak positions. The method, termed PASSPORT, is demonstrated for 4 proteins with 100 – 250 amino acids using 3D NHCA and a 3D CBCA(CO)NH experiments as input producing correct assignments with high reliability for 22% of the residues. The method, which works best for Gly, Ala, Ser, and Thr residues, provides assignments that serve as anchor points for additional assignments by both manual and semi-automated methods or they can be directly used for further studies, e.g. on ligand binding, protein dynamics, or post-translational modification, such as phosphorylation. PMID:25863893

Direct assignment of the cysteinyl, the slowly exchangeable, and the aromatic ring H nuclear magnetic resonances in clostridial-type ferredoxins. [Clostridium acidi-urici, C. pasteurianum, C. perfringens, Peptococcus aerogenes

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

Packer, E.L.; Sweeney, W.V.; Rabinowitz, J.C.

1977-04-10

We have directly assigned the /sup 1/H NMR corresponding to the cysteinyl protons, the slowly exchangeable protons, and the aromatic ring protons in the /sup 1/H NMR spectrum of Clostridium acidi-urici ferredoxin by isotopic labeling and /sup 13/C NMR decoupling techniques. We also show that the resonance pattern in the 8- to 20-ppM (from 2,2-dimethyl-2-sialapentanesulfonic acid) region of the /sup 1/H NMR spectra of oxidized Clostridium acidi-urici, Clostridium pasteurianum, Clostridium perfringens, and Peptococcus aerogenes ferredoxins are very similar, and we assign the resonances in this region by analogy with the spectrum of C. acidi-urici ferredoxin. The /sup 1/H NMR spectramore » of the ..beta.. protons of the cysteinyl residues of these ferredoxins differ, however, from the /sup 1/H NMR spectra of equivalent ..beta.. protons of the methylene carbon atoms bonded via a sulfur atom to (4Fe-4S) clusters in synthetic inorganic analogues. In the spectra of the synthetic compounds, the ..beta.. protons appear as a single resonance shifted 10 ppM from its unbonded reference position. In the spectra of oxidized clostridial ferredoxins, the cysteinyl ..beta.. protons appear as a series of at least eight resolved resonances with shifts that range from 6 to 14 ppM, relative to the free amino acid resonance position.« less

Contact replacement for NMR resonance assignment.

PubMed

Xiong, Fei; Pandurangan, Gopal; Bailey-Kellogg, Chris

2008-07-01

Complementing its traditional role in structural studies of proteins, nuclear magnetic resonance (NMR) spectroscopy is playing an increasingly important role in functional studies. NMR dynamics experiments characterize motions involved in target recognition, ligand binding, etc., while NMR chemical shift perturbation experiments identify and localize protein-protein and protein-ligand interactions. The key bottleneck in these studies is to determine the backbone resonance assignment, which allows spectral peaks to be mapped to specific atoms. This article develops a novel approach to address that bottleneck, exploiting an available X-ray structure or homology model to assign the entire backbone from a set of relatively fast and cheap NMR experiments. We formulate contact replacement for resonance assignment as the problem of computing correspondences between a contact graph representing the structure and an NMR graph representing the data; the NMR graph is a significantly corrupted, ambiguous version of the contact graph. We first show that by combining connectivity and amino acid type information, and exploiting the random structure of the noise, one can provably determine unique correspondences in polynomial time with high probability, even in the presence of significant noise (a constant number of noisy edges per vertex). We then detail an efficient randomized algorithm and show that, over a variety of experimental and synthetic datasets, it is robust to typical levels of structural variation (1-2 AA), noise (250-600%) and missings (10-40%). Our algorithm achieves very good overall assignment accuracy, above 80% in alpha-helices, 70% in beta-sheets and 60% in loop regions. Our contact replacement algorithm is implemented in platform-independent Python code. The software can be freely obtained for academic use by request from the authors.

Novel selective TOCSY method enables NMR spectral elucidation of metabolomic mixtures

NASA Astrophysics Data System (ADS)

MacKinnon, Neil; While, Peter T.; Korvink, Jan G.

2016-11-01

Complex mixture analysis is routinely encountered in NMR-based investigations. With the aim of component identification, spectral complexity may be addressed chromatographically or spectroscopically, the latter being favored to reduce sample handling requirements. An attractive experiment is selective total correlation spectroscopy (sel-TOCSY), which is capable of providing tremendous spectral simplification and thereby enhancing assignment capability. Unfortunately, isolating a well resolved resonance is increasingly difficult as the complexity of the mixture increases and the assumption of single spin system excitation is no longer robust. We present TOCSY optimized mixture elucidation (TOOMIXED), a technique capable of performing spectral assignment particularly in the case where the assumption of single spin system excitation is relaxed. Key to the technique is the collection of a series of 1D sel-TOCSY experiments as a function of the isotropic mixing time (τm), resulting in a series of resonance intensities indicative of the underlying molecular structure. By comparing these τm -dependent intensity patterns with a library of pre-determined component spectra, one is able to regain assignment capability. After consideration of the technique's robustness, we tested TOOMIXED firstly on a model mixture. As a benchmark we were able to assign a molecule with high confidence in the case of selectively exciting an isolated resonance. Assignment confidence was not compromised when performing TOOMIXED on a resonance known to contain multiple overlapping signals, and in the worst case the method suggested a follow-up sel-TOCSY experiment to confirm an ambiguous assignment. TOOMIXED was then demonstrated on two realistic samples (whisky and urine), where under our conditions an approximate limit of detection of 0.6 mM was determined. Taking into account literature reports for the sel-TOCSY limit of detection, the technique should reach on the order of 10 μ M sensitivity. We anticipate this technique will be highly attractive to various analytical fields facing mixture analysis, including metabolomics, foodstuff analysis, pharmaceutical analysis, and forensics.

Neutron Capture Measurements on 97Mo with the DANCE Array

NASA Astrophysics Data System (ADS)

Walker, Carrie L.

Neutron capture is a process that is crucial to understanding nucleosynthesis, reactors, and nuclear weapons. Precise knowledge of neutron capture cross-sections and level densities is necessary in order to model these high-flux environments. High-confidence spin and parity assignments for neutron resonances are of critical importance to this end. For nuclei in the A=100 mass region, the p-wave neutron strength function is at a maximum, and the s-wave strength function is at a minimum, producing up to six possible Jpi combinations. Parity determination becomes important to assigning spins in this mass region, and the large number of spin groups adds complexity to the problem. In this work, spins and parities for 97Mo resonances are assigned, and best fit models for photon strength function and level density are determined. The neutron capture-cross section for 97Mo is also determined, as are resonance parameters for neutron energies ranging from 16 eV to 2 keV.

Complete (1)H resonance assignment of beta-maltose from (1)H-(1)H DQ-SQ CRAMPS and (1)H (DQ-DUMBO)-(13)C SQ refocused INEPT 2D solid-state NMR spectra and first principles GIPAW calculations.

PubMed

Webber, Amy L; Elena, Bénédicte; Griffin, John M; Yates, Jonathan R; Pham, Tran N; Mauri, Francesco; Pickard, Chris J; Gil, Ana M; Stein, Robin; Lesage, Anne; Emsley, Lyndon; Brown, Steven P

2010-07-14

A disaccharide is a challenging case for high-resolution (1)H solid-state NMR because of the 24 distinct protons (14 aliphatic and 10 OH) having (1)H chemical shifts that all fall within a narrow range of approximately 3 to 7 ppm. High-resolution (1)H (500 MHz) double-quantum (DQ) combined rotation and multiple pulse sequence (CRAMPS) solid-state NMR spectra of beta-maltose monohydrate are presented. (1)H-(1)H DQ-SQ CRAMPS spectra are presented together with (1)H (DQ)-(13)C correlation spectra obtained with a new pulse sequence that correlates a high-resolution (1)H DQ dimension with a (13)C single quantum (SQ) dimension using the refocused INEPT pulse-sequence element to transfer magnetization via one-bond (13)C-(1)H J couplings. Compared to the observation of only a single broad peak in a (1)H DQ spectrum recorded at 30 kHz magic-angle spinning (MAS), the use of DUMBO (1)H homonuclear decoupling in the (1)H DQ CRAMPS experiment allows the resolution of distinct DQ correlation peaks which, in combination with first-principles chemical shift calculations based on the GIPAW (Gauge Including Projector Augmented Waves) plane-wave pseudopotential approach, enables the assignment of the (1)H resonances to the 24 distinct protons. We believe this to be the first experimental solid-state NMR determination of the hydroxyl OH (1)H chemical shifts for a simple sugar. Variable-temperature (1)H-(1)H DQ CRAMPS spectra reveal small increases in the (1)H chemical shifts of the OH resonances upon decreasing the temperature from 348 K to 248 K.

Systematic assignment of Feshbach resonances via an asymptotic bound state model

NASA Astrophysics Data System (ADS)

Goosen, Maikel; Kokkelmans, Servaas

2008-05-01

We present an Asymptotic Bound state Model (ABM), which is useful to predict Feshbach resonances. The model utilizes asymptotic properties of the interaction potentials to represent coupled molecular wavefunctions. The bound states of this system give rise to Feshbach resonances, localized at the magnetic fields of intersection of these bound states with the scattering threshold. This model was very successful to assign measured Feshbach resonances in an ultra cold mixture of ^6Li and ^40K atomsootnotetextE. Wille, F.M. Spiegelhalder, G. Kerner, D. Naik, A. Trenkwalder, G. Hendl, F. Schreck, R. Grimm, T.G. Tiecke, J.T.M. Walraven, S.J.J.M.F. Kokkelmans, E. Tiesinga, P.S. Julienne, arXiv:0711.2916. For this system, the accuracy of the determined scattering lengths is comparable to full coupled channels results. However, it was not possible to predict the width of the resonances. We discuss how an incorporation of threshold effects will improve the model, and we apply it to a mixture of ^87Rb and ^133Cs atoms, where recently Feshbach resonances have been measured.

1H, 13C, and 15N resonance assignments for the protein coded by gene locus BB0938 of Bordetella bronchiseptica

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

Rossi, Paolo; Ramelot, Theresa A.; Xiao, Rong

2005-11-01

The product of gene locus BB0938 from Bordetella bronchiseptica (Swiss-Prot ID: Q7WNU7-BORBR; NESG target ID: BoR11; Wunderlich et al., 2004; Pfam ID: PF03476) is a 128-residue protein of unknown function. This broadly conserved protein family is found in eubacteria and eukaryotes. Using triple resonance NMR techniques, we have determined 98% of backbone and 94% of side chain 1H, 13C, and 15N resonance assignments. The chemical shift and 3J(HN?Ha) scalar coupling data reveal a b topology with a seven-residue helical insert, ??????????. BMRB deposit with accession number 6693. Reference: Wunderlich et al. (2004) Proteins, 56, 181?187.

1H, 13C, and 15N resonance assignments for Escherichia coli ytfP, a member of the broadly conserved UPF0131 protein domain family

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

Aramini, James M.; Swapna, G.V.T.; Huang, Yuanpeng

2005-11-01

Protein ytfP from Escherichia coli (Swiss-Prot ID: YTFP-ECOLI; NESG target ID: ER111; Wunderlich et al., 2004) is a 113-residue member of the UPF0131 protein family (Pfam ID: PF03674) of unknown function. This domain family is found in organisms from all three kingdoms, archaea, eubacteria and eukaryotes. Using triple resonance NMR techniques, we have determined 97% of backbone and 91% of side chain 1H, 13C, and 15N resonance assignments. The chemical shift and 3J(HN?Ha) scalar coupling data reveal a mixed a/b topology,????????. BMRB deposit with Accession No. 6448. Reference: Wunderlich et al. (2004) Proteins, 56, 181?187.

Resonant photoluminescence studies of carrier localisation in c-plane InGaN/GaN quantum well structures

NASA Astrophysics Data System (ADS)

Blenkhorn, W. E.; Schulz, S.; Tanner, D. S. P.; Oliver, R. A.; Kappers, M. J.; Humphreys, C. J.; Dawson, P.

2018-05-01

In this paper we report on changes in the form of the low temperature (12 K) photoluminescence spectra of an InGaN/GaN quantum well structure as a function of excitation photon energy. As the photon energy is progressively reduced we observe at a critical energy a change in the form of the spectra from one which is determined by the occupation of the complete distribution of hole localisation centres to one which is determined by the resonant excitation of specific localisation sites. This change is governed by an effective mobility edge whereby the photo-excited holes remain localised at their initial energy and are prevented from scattering to other localisation sites. This assignment is confirmed by the results of atomistic tight binding calculations which show that the wave function overlap of the lowest lying localised holes with other hole states is low compared with the overlap of higher lying hole states with other higher lying hole states.

Millimeter-wave optical double resonance schemes for rapid assignment of perturbed spectra, with applications to the C{sup ~} {sup 1}B{sub 2} state of SO{sub 2}

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

Park, G. Barratt, E-mail: barratt@mit.edu, E-mail: barratt.park@gmail.com; Womack, Caroline C.; Jiang, Jun

2015-04-14

Millimeter-wave detected, millimeter-wave optical double resonance (mmODR) spectroscopy is a powerful tool for the analysis of dense, complicated regions in the optical spectra of small molecules. The availability of cavity-free microwave and millimeter wave spectrometers with frequency-agile generation and detection of radiation (required for chirped-pulse Fourier-transform spectroscopy) opens up new schemes for double resonance experiments. We demonstrate a multiplexed population labeling scheme for rapid acquisition of double resonance spectra, probing multiple rotational transitions simultaneously. We also demonstrate a millimeter-wave implementation of the coherence-converted population transfer scheme for background-free mmODR, which provides a ∼10-fold sensitivity improvement over the population labeling scheme.more » We analyze perturbations in the C{sup ~} state of SO{sub 2}, and we rotationally assign a b{sub 2} vibrational level at 45 328 cm{sup −1} that borrows intensity via a c-axis Coriolis interaction. We also demonstrate the effectiveness of our multiplexed mmODR scheme for rapid acquisition and assignment of three predissociated vibrational levels of the C{sup ~} state of SO{sub 2} between 46 800 and 47 650 cm{sup −1}.« less

Structural study of ethyl 3-methyl-9-oxo-3-azabicyclo63.3.19nonane-1-carboxylate by two-dimensional NMR spectroscopy

NASA Astrophysics Data System (ADS)

Arias-Pérez, M. S.; Alejo, A.; Gálvez, E.; Pérez, S. M.; Santos, M. J.

1995-04-01

Ethyl 3-methyl-9-oxo-3-azabicyclo[3.3.1]nonane-1-carboxylate has been studied by 1H, 13C and 2D NMR spectroscopy in order to establish its conformational behaviour. The combined use of COSY and 1H- 13C correlation spectra helped in the unambiguous and complete assignment of the bicyclic carbon and proton resonances. It is found that the piperidone ring displays a slightly fattened chair conformation with the N-methyl group in the equatorial position, while a twist-chair form seems to be favoured for the cyclohexanone one. Two preferred orientations migth be proposed for the ethoxycarbonyl moiety.

A non-uniformly sampled 4D HCC(CO)NH-TOCSY experiment processed using maximum entropy for rapid protein sidechain assignment

PubMed Central

Mobli, Mehdi; Stern, Alan S.; Bermel, Wolfgang; King, Glenn F.; Hoch, Jeffrey C.

2010-01-01

One of the stiffest challenges in structural studies of proteins using NMR is the assignment of sidechain resonances. Typically, a panel of lengthy 3D experiments are acquired in order to establish connectivities and resolve ambiguities due to overlap. We demonstrate that these experiments can be replaced by a single 4D experiment that is time-efficient, yields excellent resolution, and captures unique carbon-proton connectivity information. The approach is made practical by the use of non-uniform sampling in the three indirect time dimensions and maximum entropy reconstruction of the corresponding 3D frequency spectrum. This 4D method will facilitate automated resonance assignment procedures and it should be particularly beneficial for increasing throughput in NMR-based structural genomics initiatives. PMID:20299257

Evidence for two interconverting protein isomers in the methotrexate complex of dihydrofolate reductase from Escherichia coli

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

Falzone, C.J.; Benkovic, S.J.; Wright, P.E.

1991-02-26

Two-dimensional {sup 1}H NMR methods and a knowledge of the X-ray crystal structure have been used to make resonance assignments for the amino acid side chains of dihydrofolate reductase from Escherichia coli complexed with methotrexate. The H7 proton on the pteridine ring of methotrexate was found to have NOEs to the methyl protons of Leu-28 which were assigned by using the L28F mutant. These NOEs indicated that the orientation of the methotrexate pteridine ring is similar in both solution and crystal structures. During the initial assignment process, it became evident that many of the resonances in this complex, unlike thosemore » of the folate complex, are severally broadened or doubled. The observation of two distinct sets of resonances in a ratio of approximately 2:1 was attributed to the presence of two protein isomers. Many of the side chains with clearly doubled resonances were located in the {beta}-sheet and the active site. Preliminary studies on the apoprotein also revealed doubled resonances in the absence of the inhibitor, indicating the existence of the protein isomers prior to methotrexate binding. In contrast to the methotrexate complex, the binary complex with folate and the ternary MTX-NADPH-DHFR complex presented a single enzyme form. These results are proposed to reflect the ability of folate and NADPH to bind predominantly to one protein isomer.« less

Intervalley double resonance processes in MoS2

NASA Astrophysics Data System (ADS)

Wang, Yuanxi; Carvalho, Bruno; Malard, Leandro; Fantini, Cristiano; Crespi, Vincent; Pimenta, Marcos

Intervalley scattering plays a significant role in electronic energy dissipation in semiconductors. We investigate the intervalley scattering of monolayer and few-layer MoS2, by combining density functional theory calculations and resonant Raman spectroscopy probed by up to 20 laser excitation energies. We observe that two Raman peaks within 420-460 cm-1 are dispersive over a small range of laser energy, a clear signature of second-order processes involving intervalley scattering. Both modes involve LA and TA phonons at or near the K point. A third Raman peak at 466 cm-1 shows a strong intensity dependence on the layer number and is assigned 2LA(M). Our results invalidate previous Raman peak assignment proposals and open up a better understanding of double resonance processes in transition metal dichalcogenides.

Low-energy-electron scattering by CH3CN

NASA Astrophysics Data System (ADS)

Maioli, Leticia S.; Bettega, Márcio H. F.

2017-12-01

We report integral and differential cross sections for the elastic scattering of low-energy electrons by methyl cyanide (CH3CN), also known as acetonitrile. The cross sections were computed using the Schwinger multichannel method implemented with pseudopotentials. The fixed-nuclei scattering calculations were performed in the static-exchange and static-exchange plus polarization approximations for energies up to 15 eV. In our calculations with polarization effects, we found a π* shape resonance at around 2.22 eV and a broad structure associated to a σ* shape resonance at around 7 eV. The low-lying resonance was assigned to the electron capture by the two-fold degenerate π* orbital of the E symmetry of C3v group; the second was assigned to a σ* shape resonance in the A1 symmetry. We compared our cross sections with theoretical results and experimental data available in the literature, and in general we found good agreement for the positions of the two resonances. Contribution to the Topical Issue: "Low Energy Positron and Electron Interactions", edited by James Sullivan, Ron White, Michael Bromley, Ilya Fabrikant, and David Cassidy.

Empirical Equation Based Chirality (n, m) Assignment of Semiconducting Single Wall Carbon Nanotubes from Resonant Raman Scattering Data

PubMed Central

Arefin, Md Shamsul

2012-01-01

This work presents a technique for the chirality (n, m) assignment of semiconducting single wall carbon nanotubes by solving a set of empirical equations of the tight binding model parameters. The empirical equations of the nearest neighbor hopping parameters, relating the term (2n− m) with the first and second optical transition energies of the semiconducting single wall carbon nanotubes, are also proposed. They provide almost the same level of accuracy for lower and higher diameter nanotubes. An algorithm is presented to determine the chiral index (n, m) of any unknown semiconducting tube by solving these empirical equations using values of radial breathing mode frequency and the first or second optical transition energy from resonant Raman spectroscopy. In this paper, the chirality of 55 semiconducting nanotubes is assigned using the first and second optical transition energies. Unlike the existing methods of chirality assignment, this technique does not require graphical comparison or pattern recognition between existing experimental and theoretical Kataura plot. PMID:28348319

CHARACTERIZATION OF METABOLITES IN SMALL FISH BIOFLUIDS AND TISSUES BY NMR SPECTROSCOPY

EPA Science Inventory

Nuclear magnetic resonance (NMR) spectroscopy has been utilized for assessing ecotoxicity in small fish models by means of metabolomics. Two fundamental challenges of NMR-based metabolomics are the detection limit and characterization of metabolites (or NMR resonance assignments...

Measuring homework completion in behavioral activation.

PubMed

Busch, Andrew M; Uebelacker, Lisa A; Kalibatseva, Zornitsa; Miller, Ivan W

2010-07-01

The aim of this study was to develop and validate an observer-based coding system for the characterization and completion of homework assignments during Behavioral Activation (BA). Existing measures of homework completion are generally unsophisticated, and there is no current measure of homework completion designed to capture the particularities of BA. The tested scale sought to capture the type of assignment, realm of functioning targeted, extent of completion, and assignment difficulty. Homework assignments were drawn from 12 (mean age = 48, 83% female) clients in two trials of a 10-session BA manual targeting treatment-resistant depression in primary care. The two coders demonstrated acceptable or better reliability on most codes, and unreliable codes were dropped from the proposed scale. In addition, correlations between homework completion and outcome were strong, providing some support for construct validity. Ultimately, this line of research aims to develop a user-friendly, reliable measure of BA homework completion that can be completed by a therapist during session.

Backbone chemical shift assignments for the sensor domain of the Burkholderia pseudomallei histidine kinase RisS: "missing" resonances at the dimer interface.

PubMed

Buchko, Garry W; Edwards, Thomas E; Hewitt, Stephen N; Phan, Isabelle Q H; Van Voorhis, Wesley C; Miller, Samuel I; Myler, Peter J

2015-10-01

Using a deuterated sample, all the observable backbone (1)H(N), (15)N, (13)C(a), and (13)C' chemical shifts for the dimeric, periplasmic sensor domain of the Burkholderia pseudomallei histidine kinase RisS were assigned. Approximately one-fifth of the amide resonances are "missing" in the (1)H-(15)N HSQC spectrum and map primarily onto α-helices at the dimer interface observed in a crystal structure suggesting this region either undergoes intermediate timescale motion (μs-ms) and/or is heterogeneous.

Reduced dimensionality tailored HN(C)N experiments for facile backbone resonance assignment of proteins through unambiguous identification of sequential HSQC peaks

NASA Astrophysics Data System (ADS)

Kumar, Dinesh

2013-12-01

Two novel reduced dimensionality (RD) tailored HN(C)N [S.C. Panchal, N.S. Bhavesh, R.V. Hosur, Improved 3D triple resonance experiments, HNN and HN(C)N, for HN and 15N sequential correlations in (13C, 15N) labeled proteins: application to unfolded proteins, J. Biomol. NMR 20 (2001) 135-147] experiments are proposed to facilitate the backbone resonance assignment of proteins both in terms of its accuracy and speed. These experiments - referred here as (4,3)D-hNCOcaNH and (4,3)D-hNcoCANH - exploit the linear combination of backbone 15N and 13C‧/13Cα chemical shifts simultaneously to achieve higher peak dispersion and randomness along their respective F1 dimensions. Simply, this has been achieved by modulating the backbone 15N(i) chemical shifts with that of 13C‧ (i - 1)/13Cα (i - 1) spins following the established reduced dimensionality NMR approach [T. Szyperski, D.C. Yeh, D.K. Sukumaran, H.N. Moseley, G.T. Montelione, Reduced-dimensionality NMR spectroscopy for high-throughput protein resonance assignment, Proc. Natl. Acad. Sci. USA 99 (2002) 8009-8014]. Though the modification is simple it has resulted an ingenious improvement of HN(C)N both in terms of peak dispersion and easiness of establishing the sequential connectivities. The increased dispersion along F1 dimension solves two purposes here: (i) resolves the ambiguities arising because of degenerate 15N chemical shifts and (ii) reduces the signal overlap in F2(15N)-F3(1H) planes (an important requisite in HN(C)N based assignment protocol for facile and unambiguous identification of sequentially connected HSQC peaks). The performance of both these experiments and the assignment protocol has been demonstrated using bovine apo Calbindin-d9k (75 aa) and urea denatured UNC60B (a 152 amino acid ADF/cofilin family protein of Caenorhabditis elegans), as representatives of folded and unfolded protein systems, respectively.

3μm - 1.6μm Double Resonance Spectroscopy of CH_4

NASA Astrophysics Data System (ADS)

Schwartz, George; Belaas, Erik; Yang, Shaoyue; Lehmann, Kevin

2016-06-01

The Near-IR Spectrum of CH_4 is dense with many overlapping bands that perturb each other by vibrational and ro-vibrational interactions. Assignments of the individual lines are needed in order to simulate the spectrum as a function of pressure and temperature, as needed in the search for CH_4 in extrasolar planets. Both the group at the University College, London^1 and that at the University of Reins^2 have produced theoretical spectra that allows simulation up to the high temperatures expected on ``Hot Jupiters''. The accuracy of these theoretical spectra need to be further tested. Because CH_4 is a light spherical top, assignment of its perturbed spectra is a formable challenge as none of the lines allowed in the rigid rotor approximation have ground vibrational state combination differences. We are using IR-IR double resonance to observe modulation in the strength of near-IR absorption caused by a modulation of a 3 μm OPO beam that is tuned to a particular transition in the C-H stretching fundamental of CH_4. This produces V-type double resonance transitions (which share the lower state with the pump transition), which provides firm assignments for lines normally observed in absorption in the near-IR. We also observe sequential double resonance which reveals transitions that have a known rotational level of the ν_3 fundamental as the lower state and reaches final states in the 9000 cm-1 spectral region. These are states of A, E, F_1 vibrational symmetries which are forbidden in transitions from the ground vibrational state. These 3 level double resonance transitions are Doppler Free and have a linewidth of ˜10 MHz due to a combination of near-IR laser jitter and power broadening of the mid-IR transition. We also observed many 4-level double resonance transitions that we have tentatively assigned as arising from the ν_4 fundamental level. These are distinguished from the 3-level double resonance transitions by they being Doppler broadened and having a large phase shift relative to the intensity modulation. 1. S.N. Yurchenko, PNAS 111 9379-83 (2014); 2. M. Rey, JQSRT 18, 207-220 (2015), PCCP 18, 176-189 (2016)

Rapid measurement of 3J(H N-H alpha) and 3J(N-H beta) coupling constants in polypeptides.

PubMed

Barnwal, Ravi Pratap; Rout, Ashok K; Chary, Kandala V R; Atreya, Hanudatta S

2007-12-01

We present two NMR experiments, (3,2)D HNHA and (3,2)D HNHB, for rapid and accurate measurement of 3J(H N-H alpha) and 3J(N-H beta) coupling constants in polypeptides based on the principle of G-matrix Fourier transform NMR spectroscopy and quantitative J-correlation. These experiments, which facilitate fast acquisition of three-dimensional data with high spectral/digital resolution and chemical shift dispersion, will provide renewed opportunities to utilize them for sequence specific resonance assignments, estimation/characterization of secondary structure with/without prior knowledge of resonance assignments, stereospecific assignment of prochiral groups and 3D structure determination, refinement and validation. Taken together, these experiments have a wide range of applications from structural genomics projects to studying structure and folding in polypeptides.

(1)H, (13)C, and (15)N backbone resonance assignments of the full-length 40 kDa S. acidocaldarius Y-family DNA polymerase, dinB homolog.

PubMed

Moro, Sean L; Cocco, Melanie J

2015-10-01

The dinB homolog (Dbh) is a member of the Y-family of translesion DNA polymerases, which are specialized to accurately replicate DNA across from a wide variety of lesions in living cells. Lesioned bases block the progression of high-fidelity polymerases and cause detrimental replication fork stalling; Y-family polymerases can bypass these lesions. The active site of the translesion synthesis polymerase is more open than that of a replicative polymerase; consequently Dbh polymerizes with low fidelity. Bypass polymerases also have low processivity. Short extension past the lesion allows the high-fidelity polymerase to switch back onto the site of replication. Dbh and the other Y-family polymerases have been used as structural models to investigate the mechanisms of DNA polymerization and lesion bypass. Many high-resolution crystal structures of Y-family polymerases have been reported. NMR dynamics studies can complement these structures by providing a measure of protein motions. Here we report the (15)N, (1)H, and (13)C backbone resonance assignments at two temperatures (35 and 50 °C) for Sulfolobus acidocaldarius Dbh polymerase. Backbone resonance assignments have been obtained for 86 % of the residues. The polymerase active site is assigned as well as the majority of residues in each of the four domains.

Motivating Reading Compliance: Adaptation of Monte Carlo Quizzes for Online Delivery.

PubMed

Azzarello, Jo; Ogans, Judy; Robertson, Victoria

Getting students to complete reading assignments is often a source of frustration for nurse educators. Monte Carlo Quizzes (MCQs) were adapted for online delivery in a hybrid nursing course to encourage timely completion and deep processing of readings. Students indicated that MCQs motivated them to complete the assigned readings and to read more carefully. However, there were no significant differences on scores for other course assignments between those who completed readings and those who did not.

Fermi resonance in CO2: Mode assignment and quantum nuclear effects from first principles molecular dynamics

NASA Astrophysics Data System (ADS)

Basire, Marie; Mouhat, Félix; Fraux, Guillaume; Bordage, Amélie; Hazemann, Jean-Louis; Louvel, Marion; Spezia, Riccardo; Bonella, Sara; Vuilleumier, Rodolphe

2017-04-01

Vibrational spectroscopy is a fundamental tool to investigate local atomic arrangements and the effect of the environment, provided that the spectral features can be correctly assigned. This can be challenging in experiments and simulations when double peaks are present because they can have different origins. Fermi dyads are a common class of such doublets, stemming from the resonance of the fundamental excitation of a mode with the overtone of another. We present a new, efficient approach to unambiguously characterize Fermi resonances in density functional theory (DFT) based simulations of condensed phase systems. With it, the spectral features can be assigned and the two resonating modes identified. We also show how data from DFT simulations employing classical nuclear dynamics can be post-processed and combined with a perturbative quantum treatment at a finite temperature to include analytically thermal quantum nuclear effects. The inclusion of these effects is crucial to correct some of the qualitative failures of the Newtonian dynamics simulations at a low temperature such as, in particular, the behavior of the frequency splitting of the Fermi dyad. We show, by comparing with experimental data for the paradigmatic case of supercritical CO2, that these thermal quantum effects can be substantial even at ambient conditions and that our scheme provides an accurate and computationally convenient approach to account for them.

Covariance NMR Processing and Analysis for Protein Assignment.

PubMed

Harden, Bradley J; Frueh, Dominique P

2018-01-01

During NMR resonance assignment it is often necessary to relate nuclei to one another indirectly, through their common correlations to other nuclei. Covariance NMR has emerged as a powerful technique to correlate such nuclei without relying on error-prone peak peaking. However, false-positive artifacts in covariance spectra have impeded a general application to proteins. We recently introduced pre- and postprocessing steps to reduce the prevalence of artifacts in covariance spectra, allowing for the calculation of a variety of 4D covariance maps obtained from diverse combinations of pairs of 3D spectra, and we have employed them to assign backbone and sidechain resonances in two large and challenging proteins. In this chapter, we present a detailed protocol describing how to (1) properly prepare existing 3D spectra for covariance, (2) understand and apply our processing script, and (3) navigate and interpret the resulting 4D spectra. We also provide solutions to a number of errors that may occur when using our script, and we offer practical advice when assigning difficult signals. We believe such 4D spectra, and covariance NMR in general, can play an integral role in the assignment of NMR signals.

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

When species matches are unavailable are DNA barcodes correctly assigned to higher taxa? An assessment using sphingid moths

PubMed Central

2011-01-01

Background When a specimen belongs to a species not yet represented in DNA barcode reference libraries there is disagreement over the effectiveness of using sequence comparisons to assign the query accurately to a higher taxon. Library completeness and the assignment criteria used have been proposed as critical factors affecting the accuracy of such assignments but have not been thoroughly investigated. We explored the accuracy of assignments to genus, tribe and subfamily in the Sphingidae, using the almost complete global DNA barcode reference library (1095 species) available for this family. Costa Rican sphingids (118 species), a well-documented, diverse subset of the family, with each of the tribes and subfamilies represented were used as queries. We simulated libraries with different levels of completeness (10-100% of the available species), and recorded assignments (positive or ambiguous) and their accuracy (true or false) under six criteria. Results A liberal tree-based criterion assigned 83% of queries accurately to genus, 74% to tribe and 90% to subfamily, compared to a strict tree-based criterion, which assigned 75% of queries accurately to genus, 66% to tribe and 84% to subfamily, with a library containing 100% of available species (but excluding the species of the query). The greater number of true positives delivered by more relaxed criteria was negatively balanced by the occurrence of more false positives. This effect was most sharply observed with libraries of the lowest completeness where, for example at the genus level, 32% of assignments were false positives with the liberal criterion versus < 1% when using the strict. We observed little difference (< 8% using the liberal criterion) however, in the overall accuracy of the assignments between the lowest and highest levels of library completeness at the tribe and subfamily level. Conclusions Our results suggest that when using a strict tree-based criterion for higher taxon assignment with DNA barcodes, the likelihood of assigning a query a genus name incorrectly is very low, if a genus name is provided it has a high likelihood of being accurate, and if no genus match is available the query can nevertheless be assigned to a subfamily with high accuracy regardless of library completeness. DNA barcoding often correctly assigned sphingid moths to higher taxa when species matches were unavailable, suggesting that barcode reference libraries can be useful for higher taxon assignments long before they achieve complete species coverage. PMID:21806794

ESR, electrochemical and cyclodextrin-inclusion studies of triazolopyridyl pyridyl ketones and dipyridyl ketones derivatives

NASA Astrophysics Data System (ADS)

Olea-Azar, C.; Abarca, B.; Norambuena, E.; Opazo, L.; Jullian, C.; Valencia, S.; Ballesteros, R.; Chadlaoui, M.

2008-11-01

The electron spin resonance (ESR) spectra of free radicals obtained by electrolytic reduction of triazolopyridyl pyridyl ketones and dipyridyl ketones derivatives were measured in dimethylsulfoxide (DMSO). The hyperfine patterns indicate that the spin density delocalization is dependent of the rings presented in the molecule. The electrochemistry of these compounds was characterized using cyclic voltammetry, in DMSO as solvent. When one carbonyl is present in the molecule one step in the reduction mechanism was observed while two carbonyl are present two steps were detected. The first wave was assigned to the generation of the correspondent free radical species, and the second wave was assigned to the dianion derivatives. The phase-solubility measurements indicated an interaction between molecules selected and cyclodextrins in water. These inclusion complexes are 1:1 with βCD, and HP-βCD. The values of Ks showed a different kind of complexes depending on which rings are included. AM1 and DFT calculations were performed to obtain the optimized geometries, theoretical hyperfine constants, and spin distributions, respectively. The theoretical results are in complete agreement with the experimental ones.

¹H, ¹³C and ¹⁵N resonance assignment for the human K-Ras at physiological pH.

PubMed

Vo, Uybach; Embrey, Kevin J; Breeze, Alexander L; Golovanov, Alexander P

2013-10-01

K-Ras, a member of the Ras family of small GTPases, is involved in cell growth, proliferation, differentiation and apoptosis and is frequently mutated in cancer. The activity of Ras is mediated by the inter-conversion between GTP- and GDP- bound states. This conversion is regulated by binding of effector proteins such as guanine nucleotide exchange factors and GTPase activating proteins. Previously, NMR signals from these effector-binding regions of Ras often remained unassigned and largely unobservable due to conformational exchange and polysterism inherent to this protein. In this paper, we report the complete backbone and C(β), as well as partial H(α), H(β) and C(γ), NMR assignment for human K-Ras (residues 1-166) in the GDP-bound form at a physiological pH of 7.4. These data thereby make possible detailed monitoring of the functional cycle of Ras and its interactions with nucleotides and effector proteins through the observation of fingerprint signals from all the functionally important regions of the protein.

High-performance liquid chromatography with nuclear magnetic resonance detection applied to organosilicon polymers. Part 2. Comparison with other methods.

PubMed

Blechta, Vratislav; Kurfürst, Milan; Sýkora, Jan; Schraml, Jan

2007-03-23

LC-NMR utilizing (1)H and (29)Si NMR spectroscopy is ideally suited for the analysis of silicones. It is shown that reversed phase gradient LC-NMR surpasses standard gel permeation chromatography (GPC) and diffusion ordered spectroscopy (DOSY) in the analysis of model hydride terminated polydimethylsiloxane. (1)H and (29)Si NMR in the stopped-flow arrangement leads to full identification of the components. Concentration gradient introduces a dependence of the (29)Si shifts on solvent composition, this dependence can be substantially reduced by a proposed method of referencing. It is shown that the ADEQUATE version of powerful but insensitive 2D INADEQUATE experiment can be used for complete line assignment.

Characterization and antioxidative activities of rare C(50) carotenoids-sarcinaxanthin, sarcinaxanthin monoglucoside, and sarcinaxanthin diglucoside-obtained from Micrococcus yunnanensis.

PubMed

Osawa, Ayako; Ishii, Yoko; Sasamura, Nao; Morita, Marie; Kasai, Hiroaki; Maoka, Takashi; Shindo, Kazutoshi

2010-01-01

While screening for antioxidative carotenoids from marine bacteria, we isolated and identified sarcinaxanthin and its glucosylated compounds (sarcinaxanthin monoglucoside and sarcinaxanthin diglucoside) from a moderately halophilic bacterium-Micrococcus yunnanensis strain AOY-1. In the singlet oxygen ((¹O₂) quenching model, the IC(50) values of the antioxidative activities of these carotenoids were as follows: sarcinaxanthin , 57 µM; sarcinaxanthin monoglucoside, 54 µM; and sarcinaxanthin diglucoside, 74 µM. In addition, the complete proton nuclear magnetic resonance (¹H NMR) assignments of sarcinaxanthin monoglucoside pentaacetate and sarcinaxanthin diglucoside octaacetate, and fast atom bombardment mass spectrometry/mass spectrometry (FAB-MS/MS) analyses of sarcinaxanthin and sarcinaxanthin monoglucoside are reported for the first time.

Conformation-selective resonant photoelectron imaging from dipole-bound states of cold 3-hydroxyphenoxide

NASA Astrophysics Data System (ADS)

Zhu, Guo-Zhu; Huang, Dao-Ling; Wang, Lai-Sheng

2017-07-01

We report a photoelectron imaging and photodetachment study of cryogenically cooled 3-hydroxyphenoxide (3HOP) anions, m-HO(C6H4)O-. In a previous preliminary study, two conformations of the cold 3HOP anions with different dipole bound states were observed [D. L. Huang et al., J. Phys. Chem. Lett. 6, 2153 (2015)]. Five near-threshold vibrational resonances were revealed in the photodetachment spectrum from the dipole-bound excited states of the two conformations. Here, we report a more extensive investigation of the two conformers with observation of thirty above-threshold vibrational resonances in a wide spectral range between 18 850 and 19 920 cm-1 (˜1000 cm-1 above the detachment thresholds). By tuning the detachment laser to the vibrational resonances in the photodetachment spectrum, high-resolution conformation-selective resonant photoelectron images are obtained. Using information of the autodetachment channels and theoretical vibrational frequencies, we are able to assign the resonant peaks in the photodetachment spectrum: seventeen are assigned to vibrational levels of anti-3HOP, eight to syn-3HOP, and five to overlapping vibrational levels of both conformers. From the photodetachment spectrum and the conformation-selective resonant photoelectron spectra, we have obtained fourteen fundamental vibrational frequencies for the neutral syn- and anti-m-HO(C6H4)Oṡ radicals. The possibility to produce conformation-selected neutral beams using resonant photodetachment via dipole-bound excited states of anions is discussed.

NMR resonance assignments of a hypoallergenic isoform of the major birch pollen allergen Bet v 1.

PubMed

Ahammer, Linda; Grutsch, Sarina; Wallner, Michael; Ferreira, Fatima; Tollinger, Martin

2017-10-01

In Northern America and Europe a great number of people are suffering from birch pollen allergy and pollen related food allergies. The trigger for these immunological reactions is the 17.5 kDa major birch pollen allergen Bet v 1, which belongs to the family of PR-10 (pathogenesis-related) proteins. In nature, Bet v 1 occurs as a mixture of various isoforms that possess different immunological properties despite their high sequence identities. Bet v 1.0102 (Bet v 1d), which is investigated here, is a hypoallergenic isoform of Bet v 1 and a potential candidate for allergen-specific immunotherapy. We assigned the backbone and side chain 1 H, 13 C and 15 N resonances of this protein and predicted its secondary structure. The NMR-chemical shift data indicate that Bet v 1.0102 is composed of three α-helices and a seven stranded β-sheet, in agreement with the known structure of the hyperallergenic isoform Bet v 1.0101 (Bet v 1a). Our resonance assignments create the foundation for detailed characterization of the dynamic properties of Bet v 1 isoforms by NMR relaxation measurements.

Backbone and side-chain resonance assignments of (Ca2+)4-calmodulin bound to beta calcineurin A CaMBD peptide.

PubMed

Fowler, C Andrew; Núñez Hernandez, Maria F; O'Donnell, Susan E; Yu, Liping; Shea, Madeline A

2017-10-01

Calcineurin (CaN) is a heterodimeric and highly conserved serine/threonine phosphatase (PP2B) that plays a critical role in coupling calcium signals to physiological processes including embryonic cardiac development, NF-AT-regulated gene expression in immune responses, and apoptosis. The catalytic subunit (CaN A ) has three isoforms (α, β, and γ,) in humans and seven isoforms in Paramecium. In all eukaryotes, the EF-hand protein calmodulin (CaM) regulates CaN activity in a calcium-dependent manner. The N- and C-domains of CaM (CaM N and CaM C ) recognize a CaM-binding domain (CaMBD) within an intrinsically disordered region of CaN A that precedes the auto-inhibitory domain (AID) of CaN A . Here we present nearly complete 1 H, 13 C, and 15 N resonance assignments of (Ca 2+ ) 4 -CaM bound to a peptide containing the CaMBD sequence in the beta isoform of CaN A (βCaN A -CaMBDp). Its secondary structure elements predicted from the assigned chemical shifts were in good agreement with those observed in the high-resolution structures of (Ca 2+ ) 4 -CaM bound to CaMBDs of multiple enzymes. Based on the reported literature, the CaMBD of the α isoform of CaN A can bind to CaM in two opposing orientations which may influence the regulatory function of CaM. Because a high resolution structure of (Ca 2+ ) 4 -CaM bound to βCaN A -CaMBDp has not been reported, our studies serve as a starting point for determining the solution structure of this complex. This will demonstrate the preferred orientation of (Ca 2+ ) 4 -CaM on the CaMBD as well as the orientations of CaM N and CaM C relative to each other and to the AID of βCaN A .

Resonance-enhanced multiphoton ionization (REMPI) spectroscopy of bromobenzene and its perdeuterated isotopologue: Assignment of the vibrations of the S{sub 0}, S{sub 1}, and D{sub 0}{sup +} states of bromobenzene and the S{sub 0} and D{sub 0}{sup +} states of iodobenzene

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

Andrejeva, Anna; Tuttle, William D.; Harris, Joe P.

2015-12-28

We report vibrationally resolved spectra of the S{sub 1}←S{sub 0} transition of bromobenzene using resonance-enhanced multiphoton ionization spectroscopy. We study bromobenzene-h{sub 5} as well as its perdeuterated isotopologue, bromobenzene-d{sub 5}. The form of the vibrational modes between the isotopologues and also between the S{sub 0} and S{sub 1} electronic states is discussed for each species, allowing assignment of the bands to be achieved and the activity between states and isotopologues to be established. Vibrational bands are assigned utilizing quantum chemical calculations, previous experimental results, and isotopic shifts. Previous work and assignments of the S{sub 1} spectra are discussed. Additionally, themore » vibrations in the ground state cation, D{sub 0}{sup +}, are considered, since these have also been used by previous workers in assigning the excited neutral state spectra. We also examine the vibrations of iodobenzene in the S{sub 0} and D{sub 0}{sup +} states and comment on the previous assignments of these. In summary, we have been able to assign the corresponding vibrations across the whole monohalobenzene series of molecules, in the S{sub 0}, S{sub 1}, and D{sub 0}{sup +} states, gaining insight into vibrational activity and vibrational couplings.« less

A definitive analytical spectroscopic study of Indian yellow, an ancient pigment used for dating purposes.

PubMed

de Faria, Dalva L A; Edwards, Howell G M; Careaga, Valeria; Walt, Nicholas; Maier, Marta S

2017-02-01

The Raman spectrum of tartrazine has been mistakenly reported as being that of Indian yellow in the literature, which has serious consequences for the identification of this pigment in art works regarding their authentication. Unlike tartrazine, Indian yellow (a natural mixture of the magnesium and calcium salts of euxanthic acid) exhibits in its Raman spectrum a strong fluorescent background when visible excitation is used, however, excitation in the near infrared (1064nm) permitted the observation of the Raman bands from the raw pigment with the main features placed at 1346, 1368, 1425, 1441 and 1626cm -1 . Indian yellow identification was assured by 1 H and 13 C Nuclear Magnetic Resonance characterization and the complete assignment of the proton and carbon resonances was accomplished using heteronuclear single quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), nuclear overhauser effect spectroscopy (NOESY) and 1 H- 1 H correlation spectroscopy (COSY). Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray fluorescence (XRF) analyzes were also conducted on a genuine sample of this historical pigment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Maximizing Completion and Comprehension of Reading Assignments

ERIC Educational Resources Information Center

Owen, Leanne R.

2017-01-01

The author presents self-report data from students in three upper-level undergraduate courses to illustrate the comparative effectiveness of different out-of-class assessment approaches in promoting completion and comprehension of reading assignments. Students reported agreeing or strongly agreeing that all three assignments motivated them to…

Pump-probe photoelectron velocity-map imaging of autoionizing singly excited 4s{sup 1}4p{sup 6}np{sup 1}(n=7,8) and doubly excited 4s{sup 2}4p{sup 4}5s{sup 1}6p{sup 1} resonances in atomic krypton

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

Doughty, Benjamin; Haber, Louis H.; Leone, Stephen R.

2011-10-15

Pump-probe photoelectron velocity-map imaging, using 27-eV high-harmonic excitation and 786-nm ionization, is used to resolve overlapping autoionizing resonances in atomic krypton, obtaining two-photon photoelectron angular distributions (PADs) for singly and doubly excited states. Two features in the photoelectron spectrum are assigned to singly excited 4s{sup 1}4p{sup 6}np{sup 1} (n = 7,8) configurations and four features provide information about double excitation configurations. The anisotropy parameters for the singly excited 7p configuration are measured to be {beta}{sub 2} = 1.61 {+-} 0.06 and {beta}{sub 4} = 1.54 {+-} 0.16 while the 8p configuration gives {beta}{sub 2} = 1.23 {+-} 0.19 and {beta}{submore » 4} = 0.60 {+-} 0.15. These anisotropies most likely represent the sum of overlapping PADs from states of singlet and triplet spin multiplicities. Of the four bands corresponding to ionization of doubly excited states, two are assigned to 4s{sup 2}4p{sup 4}5s{sup 1}6p{sup 1} configurations that are probed to different J-split ion states. The two remaining doubly excited states are attributed to a previously observed, but unassigned, resonance in the vacuum-ultraviolet photoabsorption spectrum. The PADs from each of the double excitation states are also influenced by overlap from neighboring states that are not completely spectrally resolved. The anisotropies of the observed double excitation states are reported, anticipating future theoretical and experimental work to separate the overlapping PADs into the state resolved PADs. The results can be used to test theories of excited state ionization.« less

Facilitated assignment of large protein NMR signals with covariance sequential spectra using spectral derivatives.

PubMed

Harden, Bradley J; Nichols, Scott R; Frueh, Dominique P

2014-09-24

Nuclear magnetic resonance (NMR) studies of larger proteins are hampered by difficulties in assigning NMR resonances. Human intervention is typically required to identify NMR signals in 3D spectra, and subsequent procedures depend on the accuracy of this so-called peak picking. We present a method that provides sequential connectivities through correlation maps constructed with covariance NMR, bypassing the need for preliminary peak picking. We introduce two novel techniques to minimize false correlations and merge the information from all original 3D spectra. First, we take spectral derivatives prior to performing covariance to emphasize coincident peak maxima. Second, we multiply covariance maps calculated with different 3D spectra to destroy erroneous sequential correlations. The maps are easy to use and can readily be generated from conventional triple-resonance experiments. Advantages of the method are demonstrated on a 37 kDa nonribosomal peptide synthetase domain subject to spectral overlap.

Chemical Assignment of Structural Isomers of Sulfur-Containing Metabolites in Garlic by Liquid Chromatography-Fourier Transform Ion Cyclotron Resonance-Mass Spectrometry.

PubMed

Nakabayashi, Ryo; Sawada, Yuji; Aoyagi, Morihiro; Yamada, Yutaka; Hirai, Masami Yokota; Sakurai, Tetsuya; Kamoi, Takahiro; Rowan, Daryl D; Saito, Kazuki

2016-02-01

The chemical assignment of metabolites is crucial to understanding the relation between food composition and biological activity. This study was designed to detect and chemically assign sulfur-containing metabolites by using LC-Fourier transform ion cyclotron resonance-mass spectrometry (FTICR-MS) in Allium plants. Ultrahigh resolution (>250,000 full width at half-maximum) and mass accuracy (<1 mDa) by FTICR-MS allowed us to distinguish ions containing sulfur isotopes ((32)S and (34)S). Putative 69 S-containing monoisotopic ions (S-ions) were extracted from the metabolome data of onion (Allium cepa), green onion (Allium fistulosum), and garlic (Allium sativum) on the basis of theoretical mass differences between (32)S-ions and their (34)S-substituted counterparts and on the natural abundance of (34)S. Eight S-ions were chemically assigned by using the reference data according to the guidelines of the Metabolomics Standards Initiative. Three ions detected in garlic were assigned as derived from the isomers γ-glutamyl-S-1-propenylcysteine and γ-glutamyl-S-2-propenylcysteine and as S-2-propenylmercaptoglutathione on the basis of differences in key product ions identified in reference tandem MS spectra. The ability to discriminate between such geometric isomers will be extremely useful for the chemical assignment of unknown metabolites in MS-based metabolomics. © 2016 American Society for Nutrition.

Hyperpolarized [U-(2) H, U-(13) C]Glucose reports on glycolytic and pentose phosphate pathway activity in EL4 tumors and glycolytic activity in yeast cells.

PubMed

Timm, Kerstin N; Hartl, Johannes; Keller, Markus A; Hu, De-En; Kettunen, Mikko I; Rodrigues, Tiago B; Ralser, Markus; Brindle, Kevin M

2015-12-01

A resonance at ∼181 ppm in the (13) C spectra of tumors injected with hyperpolarized [U-(2) H, U-(13) C]glucose was assigned to 6-phosphogluconate (6PG), as in previous studies in yeast, whereas in breast cancer cells in vitro this resonance was assigned to 3-phosphoglycerate (3PG). These peak assignments were investigated here using measurements of 6PG and 3PG (13) C-labeling using liquid chromatography tandem mass spectrometry (LC-MS/MS) METHODS: Tumor-bearing mice were injected with (13) C6 glucose and the (13) C-labeled and total 6PG and 3PG concentrations measured. (13) C MR spectra of glucose-6-phosphate dehydrogenase deficient (zwf1Δ) and wild-type yeast were acquired following addition of hyperpolarized [U-(2) H, U-(13) C]glucose and again (13) C-labeled and total 6PG and 3PG were measured by LC-MS/MS RESULTS: Tumor (13) C-6PG was more abundant than (13) C-2PG/3PG and the resonance at ∼181 ppm matched more closely that of 6PG. (13) C MR spectra of wild-type and zwf1Δ yeast cells showed a resonance at ∼181 ppm after labeling with hyperpolarized [U-(2) H, U-(13) C]glucose, however, there was no 6PG in zwf1Δ cells. In the wild-type cells 3PG was approximately four-fold more abundant than 6PG CONCLUSION: The resonance at ∼181 ppm in (13) C MR spectra following injection of hyperpolarized [U-(2) H, U-(13) C]glucose originates predominantly from 6PG in EL4 tumors and 3PG in yeast cells. © 2014 Wiley Periodicals, Inc.

Laser-polarized xenon-129 magnetic resonance spectroscopy and imaging. The development of a method for in vivo perfusion measurement

NASA Astrophysics Data System (ADS)

Rosen, Matthew Scot

2001-07-01

This thesis presents in vivo nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) studies with laser-polarized 129Xe delivered to living rats by inhalation and transported to tissue via blood flow. The results presented herein include the observation, assignment, and dynamic measurement of 129Xe resonances in the brain and body, the first one- and two-dimensional chemical-shift-resolved images of 129Xe in blood, tissue, and gas in the thorax, and the first images of 129Xe in brain tissue. These results establish that laser-polarized 129Xe can be used as a magnetic resonance tracer in vivo. NMR resonances at 0, 191, 198, and 209 ppm relative to the 129 Xe gas resonance are observed in the rat thorax and assigned to 129Xe in gas, fat, tissue, and blood respectively. Resonances at 189, 192, 195, 198, and 209 ppm are observed in the brain, and the 195 and 209 ppm resonances are assigned to 129Xe in grey matter, and blood, respectively. The design and construction of a laser-polarized 129Xe production and delivery system is described. This system produces liter-volumes of laser- polarized 129Xe by spin-exchange optical- pumping. It represented an order of magnitude increase over previously reported production volumes of polarized 129Xe. At approximately 3-7% polarization, 157 cc-atm of xenon is produced and stored as ice every 5 minutes. This reliable, effective, and simple production method for large volumes of 129Xe can be applied to other areas of research involving the use of laser-polarized noble gases. A model of the in vivo transport of laser polarized 129Xe to tissue under realistic experimental NMR conditions is described. Appropriate control of the NMR parameters is shown to allow tissue perfasion and 129Xe tissue T1 to be extracted from measurement of the steady-state 129Xe tissue signal. In vivo rodent 129Xe NMR results are used to estimate the signal-to-noise ratio of this technique, and an inhaled 30% xenon/70% O2 mixture polarized to 5% is estimated to provide sufficient SNR in rodent grey matter. Application to the measurement of regional cerebral blood flow and neuronal activation is discussed.

Using Self-Recording, Evaluation, and Graphing to Increase Completion of Homework Assignments.

ERIC Educational Resources Information Center

Trammel, Diana Lynn; And Others

1994-01-01

Self-monitoring procedures were effective in increasing the number of daily homework assignments completed by eight secondary level students with learning disabilities. A daily listing of all assignments given by regular classroom teachers was used. Goal setting and self-graphing of data appeared to increase self-monitoring effectiveness. (DB)

Study of inelastic decay amplitudes in /sup 51/Mn

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

Whatley, K.M.

1982-01-01

Detailed angular distribution measurments on inelastically scattered protons and de-excitation ..gamma..-rays in the /sup 50/Cr(p,p') and /sup 50/Cr(p,p'..gamma..) reactions were performed for 107 resonances in /sup 51/Mn in the proton energy range 3.0-4.4 MeV. An overall resolution of 425 eV was obtained with the tandem Van de Graaff accelerator and the high resolution system at the Triangle Universities Nuclear Laboratory. Spin and parity assignments for the 107 resonances studied were as follows: 1/2/sup +/ (4); 1/2/sup -/ (6); 3/2/sup -/ (30); 3/2/sup +/ (20); 5/2/sup +/ (38); 5/2/sup -/ (7); 7/2/sup +/ (1); and 9/2/sup +/ (1). Mixing ratios formore » the inelastic decay amplitudes were uniquely determined for all resonances except those assigned J/sup ..pi../ = 1/2/sup +/, 1/2/sup -/, or 3/2/sup +/. For 1/2/sup +/ and 1/2/sup -/ resonances there is only one open decay channel. For 3/2/sup +/ resonances, insufficient information is obtained from this experiment to determine a unique solution for the mixing ratios. Statistical studies were performed on the set of 3/2/sup -/ resonances and on the set of 5/2/sup +/ resonances. Strong channel-channel correlations were observed in the distributions of the reduced widths and the reduced width amplitudes for 5/2/sup +/ resonances. The existence of such correlations is a violation of the extreme statistical model. The present results agree with the reduced width amplitude distribution of Krieger and Porter which includes channel-channel correlations.« less

Structure of 10 N in 9 C+p resonance scattering

DOE PAGES

Hooker, J.; Rogachev, G. V.; Goldberg, V. Z.; ...

2017-03-17

We studied the structure of exotic nucleus 10N using 9C+p resonance scattering. Two ℓ=0 resonances were found to be the lowest states in 10N. Furthermore, the ground state of 10N is unbound with respect to proton decay by 2.2(2) or 1.9(2) MeV depending on the 2 -or 1 -spin-parity assignment, and the first excited state is unbound by 2.8(2) MeV.

Anion states of η4-polyene iron tricarbonyl complexes

NASA Astrophysics Data System (ADS)

Olthoff, J. K.; Moore, J. H.; Tossell, J. A.; Giordan, J. C.; Baerends, E. J.

1987-12-01

Attachment energies of low energy electrons to Fe(CO)5 and to η4 complexes of 1,3-butadiene, 1,3-cyclohexadiene, cyclooctatetraene, and cyclobutadiene with Fe(CO3) have been determined by electron transmission spectroscopy. The spectrum of Fe(CO)5 is similar to that of Cr(CO)6, showing an anion resonance near threshold assigned to predominantly Fe3d orbitals and two resonances between 1 and 3 eV assigned to predominantly COπ* orbitals.The diene complexes show threshold features similar to Fe(CO)5, COπ* resonances around 2 eV, and one or more diene π* resonances. The resonances from the lowest π* orbitals of butadiene, cyclohexadiene, and cyclooctatetraene are little different in the free dienes and the complexes, but higher π* orbitals are substantially destabilized in the complexes, consistent with qualitative symmetry arguments. In the cyclobutadiene complex the π*3 orbital of cyclobutadiene is strongly destabilized by interaction with the Fe3d, giving a resonant feature at 1.2 eV. Dissociative attachment of electrons by the iron tricarbonyl complexes has been observed mass spectrometrically. The phenomenon is observed for electrons of energy less than 2 eV and results primarily in the loss of CO. For the cyclobutadiene complex, however, the attachment of 0 eV electrons results in a complex chemical process leading to the ejection of C2.

MetaboID: a graphical user interface package for assignment of 1H NMR spectra of bodyfluids and tissues.

PubMed

MacKinnon, Neil; Somashekar, Bagganahalli S; Tripathi, Pratima; Ge, Wencheng; Rajendiran, Thekkelnaycke M; Chinnaiyan, Arul M; Ramamoorthy, Ayyalusamy

2013-01-01

Nuclear magnetic resonance based measurements of small molecule mixtures continues to be confronted with the challenge of spectral assignment. While multi-dimensional experiments are capable of addressing this challenge, the imposed time constraint becomes prohibitive, particularly with the large sample sets commonly encountered in metabolomic studies. Thus, one-dimensional spectral assignment is routinely performed, guided by two-dimensional experiments on a selected sample subset; however, a publicly available graphical interface for aiding in this process is currently unavailable. We have collected spectral information for 360 unique compounds from publicly available databases including chemical shift lists and authentic full resolution spectra, supplemented with spectral information for 25 compounds collected in-house at a proton NMR frequency of 900 MHz. This library serves as the basis for MetaboID, a Matlab-based user interface designed to aid in the one-dimensional spectral assignment process. The tools of MetaboID were built to guide resonance assignment in order of increasing confidence, starting from cursory compound searches based on chemical shift positions to analysis of authentic spike experiments. Together, these tools streamline the often repetitive task of spectral assignment. The overarching goal of the integrated toolbox of MetaboID is to centralize the one dimensional spectral assignment process, from providing access to large chemical shift libraries to providing a straightforward, intuitive means of spectral comparison. Such a toolbox is expected to be attractive to both experienced and new metabolomic researchers as well as general complex mixture analysts. Copyright © 2012 Elsevier Inc. All rights reserved.

β-delayed γ decay of 20Mg and the 19Ne(p , γ) 20 Na breakout reaction in Type I X-ray bursts

NASA Astrophysics Data System (ADS)

Glassman, B. E.; Pérez-Loureiro, D.; Wrede, C.; Allen, J.; Bardayan, D. W.; Bennett, M. B.; Brown, B. A.; Chipps, K. A.; Febbraro, M.; Friedman, M.; Fry, C.; Hall, M. R.; Hall, O.; Liddick, S. N.; O'Malley, P.; Ong, W. J.; Pain, S. D.; Prokop, C.; Schwartz, S. B.; Shidling, P.; Sims, H.; Thompson, P.; Zhang, H.

2018-03-01

Certain astrophysical environments such as thermonuclear outbursts on accreting neutron stars (Type-I X-ray bursts) are hot enough to allow for breakout from the Hot CNO hydrogen burning cycles to the rapid proton capture (rp) process. An important breakout reaction sequence is 15O(α,γ)19Ne(p,γ)20Na and the 19Ne(p,γ)20Na reaction rate is expected to be dominated by a single resonance at 457 keV above the proton threshold in 20Na. The resonance strength and, hence, reaction rate depends strongly on whether this 20Na state at an excitation energy of 2647 keV has spin and parity of 1+ or 3+. Previous 20Mg (Jπ =0+) β+ decay experiments have relied almost entirely on searches for β-delayed proton emission from this resonance in 20Na to limit the log ft value and, hence, Jπ. However there is a non-negligible γ-ray branch expected that must also be limited experimentally to determine the log ft value and constrain Jπ. We have measured the β-delayed γ decay of 20Mg to complement previous β-delayed proton decay work and provide the first complete limit based on all energetically allowed decay channels through the 2647 keV state. Our limit confirms that a 1+ assignment for this state is highly unlikely.

Nuclear magnetic resonance spectroscopy in the structure elucidation and biosynthesis of natural products

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

Meksuriyen, D.

1988-01-01

Examination of a chloroform extract of Dracaena loureiri Gagnep (Agavaceae), a Thia medicinal plant possessing antibacterial activity, has led to the isolation of fifteen flavenoids. The biogenic relationships among these flavenoids isolated were briefly discussed. Definition of the skeleton and the unambiguous assignment of all of the protons of the isolates was achieved through extensive 2D-homonuclear chemical shift correlation, nuclear Overhauser effect (NOE) difference spectroscopy and 2D-NOE experiments. The {sup 1}H and {sup 13}C NMR spectra of staurosporine, a potent biologically active agent from Streptomyces staurosporeus, were unambiguously assigned by using 2D homonuclear chemical shift correlation, NOE, {sup 1}H-detected heteronuclearmore » multiple-quantum coherence via direct coupling and via multiple-bond coupling for resonance assignments of protonated and nonprotonated carbons, respectively. S. Staurosporeus was found to utilize endogenous and exogenous D- and L-isomers of trytophan in the production of staurosporine. The biosynthesis of staurosporine was examined by employing carbon-14, tritium, and carbon-13 labeled precursors.« less

Neurochemical and Neuroanatomical Plasticity Following Memory Training and Yoga Interventions in Older Adults with Mild Cognitive Impairment.

PubMed

Yang, Hongyu; Leaver, Amber M; Siddarth, Prabha; Paholpak, Pattharee; Ercoli, Linda; St Cyr, Natalie M; Eyre, Harris A; Narr, Katherine L; Khalsa, Dharma S; Lavretsky, Helen

2016-01-01

Behavioral interventions are becoming increasingly popular approaches to ameliorate age-related cognitive decline, but their underlying neurobiological mechanisms and clinical efficiency have not been fully elucidated. The present study explored brain plasticity associated with two behavioral interventions, memory enhancement training (MET) and a mind-body practice (yogic meditation), in healthy seniors with mild cognitive impairment (MCI) using structural magnetic resonance imaging (s-MRI) and proton magnetic resonance spectroscopy ( 1 H-MRS). Senior participants (age ≥55 years) with MCI were randomized to the MET or yogic meditation interventions. For both interventions, participants completed either MET training or Kundalini Yoga (KY) for 60-min sessions over 12 weeks, with 12-min daily homework assignments. Gray matter volume and metabolite concentrations in the dorsal anterior cingulate cortex (dACC) and bilateral hippocampus were measured by structural MRI and 1 H-MRS at baseline and after 12 weeks of training. Metabolites measured included glutamate-glutamine (Glx), choline-containing compounds (Cho, including glycerophosphocholine and phosphocholine), gamma-aminobutyric acid (GABA), and N-acetyl aspartate and N-acetylaspartyl-glutamate (NAA-NAAG). In total, 11 participants completed MET and 14 completed yogic meditation for this study. Structural MRI analysis showed an interaction between time and group in dACC, indicating a trend towards increased gray matter volume after the MET intervention. 1 H-MRS analysis showed an interaction between time and group in choline-containing compounds in bilateral hippocampus, induced by significant decreases after the MET intervention. Though preliminary, our results suggest that memory training induces structural and neurochemical plasticity in seniors with MCI. Further research is needed to determine whether mind-body interventions like yoga yield similar neuroplastic changes.

Neurochemical and Neuroanatomical Plasticity Following Memory Training and Yoga Interventions in Older Adults with Mild Cognitive Impairment

PubMed Central

Yang, Hongyu; Leaver, Amber M.; Siddarth, Prabha; Paholpak, Pattharee; Ercoli, Linda; St. Cyr, Natalie M.; Eyre, Harris A.; Narr, Katherine L.; Khalsa, Dharma S.; Lavretsky, Helen

2016-01-01

Behavioral interventions are becoming increasingly popular approaches to ameliorate age-related cognitive decline, but their underlying neurobiological mechanisms and clinical efficiency have not been fully elucidated. The present study explored brain plasticity associated with two behavioral interventions, memory enhancement training (MET) and a mind-body practice (yogic meditation), in healthy seniors with mild cognitive impairment (MCI) using structural magnetic resonance imaging (s-MRI) and proton magnetic resonance spectroscopy (1H-MRS). Senior participants (age ≥55 years) with MCI were randomized to the MET or yogic meditation interventions. For both interventions, participants completed either MET training or Kundalini Yoga (KY) for 60-min sessions over 12 weeks, with 12-min daily homework assignments. Gray matter volume and metabolite concentrations in the dorsal anterior cingulate cortex (dACC) and bilateral hippocampus were measured by structural MRI and 1H-MRS at baseline and after 12 weeks of training. Metabolites measured included glutamate-glutamine (Glx), choline-containing compounds (Cho, including glycerophosphocholine and phosphocholine), gamma-aminobutyric acid (GABA), and N-acetyl aspartate and N-acetylaspartyl-glutamate (NAA-NAAG). In total, 11 participants completed MET and 14 completed yogic meditation for this study. Structural MRI analysis showed an interaction between time and group in dACC, indicating a trend towards increased gray matter volume after the MET intervention. 1H-MRS analysis showed an interaction between time and group in choline-containing compounds in bilateral hippocampus, induced by significant decreases after the MET intervention. Though preliminary, our results suggest that memory training induces structural and neurochemical plasticity in seniors with MCI. Further research is needed to determine whether mind-body interventions like yoga yield similar neuroplastic changes. PMID:27917121

The Impact of Computer-Based Assignments on Student Motivation to Complete Homework Assignments for Sixth-Grade Students

ERIC Educational Resources Information Center

Cyr, Mary Ann

2013-01-01

The purpose of this qualitative study was to examine the engagement of 11 middle school-aged students from a southeast Michigan public school, who were given laptop computers with twenty-four-hour-a-day Internet access in order to complete homework assignments. Specifically, this study examined the perceptions of sixth-grade students regarding the…

What Can Be Learned from Nuclear Resonance Vibrational Spectroscopy: Vibrational Dynamics and Hemes

PubMed Central

2017-01-01

Nuclear resonance vibrational spectroscopy (NRVS; also known as nuclear inelastic scattering, NIS) is a synchrotron-based method that reveals the full spectrum of vibrational dynamics for Mössbauer nuclei. Another major advantage, in addition to its completeness (no arbitrary optical selection rules), is the unique selectivity of NRVS. The basics of this recently developed technique are first introduced with descriptions of the experimental requirements and data analysis including the details of mode assignments. We discuss the use of NRVS to probe 57Fe at the center of heme and heme protein derivatives yielding the vibrational density of states for the iron. The application to derivatives with diatomic ligands (O2, NO, CO, CN–) shows the strong capabilities of identifying mode character. The availability of the complete vibrational spectrum of iron allows the identification of modes not available by other techniques. This permits the correlation of frequency with other physical properties. A significant example is the correlation we find between the Fe–Im stretch in six-coordinate Fe(XO) hemes and the trans Fe–N(Im) bond distance, not possible previously. NRVS also provides uniquely quantitative insight into the dynamics of the iron. For example, it provides a model-independent means of characterizing the strength of iron coordination. Prediction of the temperature-dependent mean-squared displacement from NRVS measurements yields a vibrational “baseline” for Fe dynamics that can be compared with results from techniques that probe longer time scales to yield quantitative insights into additional dynamical processes. PMID:28921972

Efficacy of chloral hydrate-hydroxyzine and chloral hydrate-midazolam in pediatric magnetic resonance imaging sedation.

PubMed

Fallah, Razieh; Fadavi, Nafiseh; Behdad, Shekofah; Fallah Tafti, Mahmoud

2014-01-01

Magnetic resonance imaging (MRI) is a useful diagnostic tool for the evaluation of congenital or acquired brain lesions. But, in all of less than 8-year-old children, pharmacological agents and procedural sedation should be used to induce motionless conditions for imaging studies. The purpose of this study was to compare the efficacy and safety of combination of chloral hydrate-hydroxyzine (CH+H) and chloral hydrate-midazolam (CH+M) in pediatric MRI sedation. In a parallel single-blinded randomized clinical trial, sixty 1-7-year-old children who underwent brain MRI, were randomly assigned to receive chloral hydrate in a minimum dosage of 40 mg/kg in combination with either 2 mg/kg of hydroxyzine or 0.5 mg/kg of midazolam. The primary outcomes were efficacy of adequate sedation (Ramsay sedation score of five) and completion of MRI examination. The secondary outcome was clinical side-effects. Twenty-eight girls (46.7%) and 32 boys (53.3%) with the mean age of 2.72±1.58 years were studied. Adequate sedation and completion of MRI were achieved in 76.7% of CH+H group. Mild and transient clinical side-effects, such as vomiting of one child in each group and agitation in 2 (6.6 %) children of CH+M group, were also seen. The adverse events were more frequent in CH+M group. Combinations of chloral hydrate-hydroxyzine and chloral hydrate-midazolam were effective in pediatric MRI sedation; however, chloral hydrate-hydroxyzine was safer.

Chemical characterization of a prominent phosphomonoester resonance from mammalian brain. 31P and 1H NMR analysis at 4.7 and 14.1 tesla

NASA Astrophysics Data System (ADS)

Pettegrew, J. W.; Kopp, S. J.; Dadok, J.; Minshew, N. J.; Feliksik, J. M.; Glonek, T.; Cohen, M. M.

A prominent 31P NMR resonance at 3.84 ppm in mammalian brain has been identified as ethanolamine phosphate. The identification was based on 1H and 31P NMR findings (including pH titrations) at 4.7 and 14.1 T, as well as thin-layer chromatography studies. We previously incorrectly assigned the 3.84 ppm resonance to ribose-5-phosphate. The incorrect assignment occurred because the two compounds have very similar 31P chemical shifts, and because we did not carefully consider the effects of counter ions and ionic strengths when interpreting the 31P chemical shifts. In separate preliminary studies we have demonstrated ethanolamine phosphate to be high in immature developing brain and in the degenerating brain of Alzheimer's and Huntington's disease patients. Ethanolamine phosphate may therefore serve as a sensitive marker of membrane phospholipid turnover for both in vitro and in vivo31P NMR studies.

Double cross-polarization MAS NMR in the assignment of abundant-spin resonances: ¹⁹F-{²⁹Si}-¹⁹F FBCP/MAS NMR of fluoride ions incorporated in calcium silicate hydrate (C-S-H) phases.

PubMed

Tran, Thuan T; Bildsøe, Henrik; Jakobsen, Hans J; Skibsted, Jørgen

2012-08-01

A new version of the double cross-polarization MAS NMR experiment, which transfers polarization Forth and Back (FBCP) between high- and low-γ spin nuclei, is presented. The pulse sequence is demonstrated by ¹⁹F-{²⁹Si}-¹⁹F and ¹⁹F-{¹³C}-¹⁹F FBCP NMR spectra of a mixture of cuspidine (Ca₄Si₂O₇F₂) and Teflon (-CF₂-)(n). The experiment is useful for assignment of the high-γ spin resonances, as demonstrated by ¹⁹F-{²⁹Si}-¹⁹F FBCP NMR of a fluoride-containing calcium-silicate-hydrate (C-S-H) phase, where the ¹⁹F resonance from fluoride ions incorporated in the interlayer structure of the C-S-H phase is identified. Copyright © 2012 Elsevier Inc. All rights reserved.

iHADAMAC: A complementary tool for sequential resonance assignment of globular and highly disordered proteins

NASA Astrophysics Data System (ADS)

Feuerstein, Sophie; Plevin, Michael J.; Willbold, Dieter; Brutscher, Bernhard

2012-01-01

An experiment, iHADAMAC, is presented that yields information on the amino-acid type of individual residues in a protein by editing the 1H- 15N correlations into seven different 2D spectra, each corresponding to a different class of amino-acid types. Amino-acid type discrimination is realized via a Hadamard encoding scheme based on four different spin manipulations as recently introduced in the context of the sequential HADAMAC experiment. Both sequential and intra-residue HADAMAC experiments yield highly complementary information that greatly facilitate resonance assignment of proteins with high frequency degeneracy, as demonstrated here for a 188-residue intrinsically disordered protein fragment of the hepatitis C virus protein NS5A.

1H, 15N and 13C backbone and side-chain resonance assignments of a family 32 carbohydrate-binding module from the Clostridium perfringens NagH.

PubMed

Grondin, Julie M; Chitayat, Seth; Ficko-Blean, Elizabeth; Boraston, Alisdair B; Smith, Steven P

2012-10-01

The Gram-positive anaerobe Clostridium perfringens is an opportunistic bacterial pathogen that secretes a battery of enzymes involved in glycan degradation. These glycoside hydrolases are thought to be involved in turnover of mucosal layer glycans, and in the spread of major toxins commonly associated with the development of gastrointestinal diseases and gas gangrene in humans. These enzymes employ multi-modularity and carbohydrate-binding function to degrade extracellular eukaryotic host sugars. Here, we report the full (1)H, (15)N and (13)C chemical shift resonance assignments of the first family 32 carbohydrate-binding module from NagH, a secreted family 84 glycoside hydrolase.

Intensity enhancement and selective detection of proximate solvent molecules by molecular near-field effect in resonance hyper-Raman scattering

NASA Astrophysics Data System (ADS)

Shimada, Rintaro; Kano, Hideaki; Hamaguchi, Hiro-o.

2008-07-01

A new molecular phenomenon associated with resonance hyper-Raman (HR) scattering in solution has been discovered. Resonance HR spectra of all-trans-β-carotene and all-trans-lycopene in various solvents exhibited several extra bands that were not assignable to the solute but were unequivocally assigned to the solvents. Neat solvents did not show detectable HR signals under the same experimental conditions. Similar experiments with all-trans-retinal did not exhibit such enhancement either. All-trans-β-carotene and all-trans-lycopene have thus been shown to induce enhanced HR scattering of solvent molecules through a novel molecular effect that is not associated with all-trans-retinal. We call this new effect the "molecular near-field effect." In order to explain this newly found effect, an extended vibronic theory of resonance HR scattering is developed where the vibronic interaction including the proximate solvent molecule (intermolecular vibronic coupling) is explicitly introduced in the solute hyperpolarizability tensor. The potential of "molecular near-field HR spectroscopy," which selectively detects molecules existing in the close vicinity of a HR probe in complex chemical or biological systems, is discussed.

Photoassociation studies of ultracold NaCs from the Cs 6(2)P(3/2) asymptote.

PubMed

Wakim, A; Zabawa, P; Bigelow, N P

2011-11-14

A combination of pulsed depletion spectroscopy and photoassociation spectroscopy is utilized to assign photoassociation spectra of NaCs. These methods investigate the ab initio Ω = 2 potential energy curve and indicate a previously unknown avoided crossing between the (3)Ω = 1 and (4)Ω = 1 electronic states. We present rotational assignments of deeply bound singlet ground state molecules, an improved C(6) coefficient for the (4)Ω = 1 and assignments for all twenty-three photoassociation resonances detuned from the Cs 6(2)P(3/2) asymptote.

Fully automatic assignment of small molecules' NMR spectra without relying on chemical shift predictions.

PubMed

Castillo, Andrés M; Bernal, Andrés; Patiny, Luc; Wist, Julien

2015-08-01

We present a method for the automatic assignment of small molecules' NMR spectra. The method includes an automatic and novel self-consistent peak-picking routine that validates NMR peaks in each spectrum against peaks in the same or other spectra that are due to the same resonances. The auto-assignment routine used is based on branch-and-bound optimization and relies predominantly on integration and correlation data; chemical shift information may be included when available to fasten the search and shorten the list of viable assignments, but in most cases tested, it is not required in order to find the correct assignment. This automatic assignment method is implemented as a web-based tool that runs without any user input other than the acquired spectra. Copyright © 2015 John Wiley & Sons, Ltd.

Resonance assignment of the NMR spectra of disordered proteins using a multi-objective non-dominated sorting genetic algorithm.

PubMed

Yang, Yu; Fritzsching, Keith J; Hong, Mei

2013-11-01

A multi-objective genetic algorithm is introduced to predict the assignment of protein solid-state NMR (SSNMR) spectra with partial resonance overlap and missing peaks due to broad linewidths, molecular motion, and low sensitivity. This non-dominated sorting genetic algorithm II (NSGA-II) aims to identify all possible assignments that are consistent with the spectra and to compare the relative merit of these assignments. Our approach is modeled after the recently introduced Monte-Carlo simulated-annealing (MC/SA) protocol, with the key difference that NSGA-II simultaneously optimizes multiple assignment objectives instead of searching for possible assignments based on a single composite score. The multiple objectives include maximizing the number of consistently assigned peaks between multiple spectra ("good connections"), maximizing the number of used peaks, minimizing the number of inconsistently assigned peaks between spectra ("bad connections"), and minimizing the number of assigned peaks that have no matching peaks in the other spectra ("edges"). Using six SSNMR protein chemical shift datasets with varying levels of imperfection that was introduced by peak deletion, random chemical shift changes, and manual peak picking of spectra with moderately broad linewidths, we show that the NSGA-II algorithm produces a large number of valid and good assignments rapidly. For high-quality chemical shift peak lists, NSGA-II and MC/SA perform similarly well. However, when the peak lists contain many missing peaks that are uncorrelated between different spectra and have chemical shift deviations between spectra, the modified NSGA-II produces a larger number of valid solutions than MC/SA, and is more effective at distinguishing good from mediocre assignments by avoiding the hazard of suboptimal weighting factors for the various objectives. These two advantages, namely diversity and better evaluation, lead to a higher probability of predicting the correct assignment for a larger number of residues. On the other hand, when there are multiple equally good assignments that are significantly different from each other, the modified NSGA-II is less efficient than MC/SA in finding all the solutions. This problem is solved by a combined NSGA-II/MC algorithm, which appears to have the advantages of both NSGA-II and MC/SA. This combination algorithm is robust for the three most difficult chemical shift datasets examined here and is expected to give the highest-quality de novo assignment of challenging protein NMR spectra.

United States Air Force Summer Faculty Research Program (1983). Program Management Report.

DTIC Science & Technology

1983-12-01

845-5011 Dr. John Eoll Degree: Ph.D., Astrophysics, 1976 Assistant Professor Specialty: Radiaton Transport , Fluid Lernir-Rhyne College Dynamics...Applications Newark, DE 19711 Assigned: RADC (302) 738-8173 Dr. Gregory Jones Degree: Ph.D., Mathematics, 1972 Associate Professor Specialty: Computability...1965 Associate Professor Specialty: Magnetic Resonance, University of Dayton Transport Properties Physics Department Assigned: ML Dayton, OH 45469 5

NMR structural and dynamical investigation of the isolated voltage-sensing domain of the potassium channel KvAP: implications for voltage gating.

PubMed

Shenkarev, Zakhar O; Paramonov, Alexander S; Lyukmanova, Ekaterina N; Shingarova, Lyudmila N; Yakimov, Sergei A; Dubinnyi, Maxim A; Chupin, Vladimir V; Kirpichnikov, Mikhail P; Blommers, Marcel J J; Arseniev, Alexander S

2010-04-28

The structure and dynamics of the isolated voltage-sensing domain (VSD) of the archaeal potassium channel KvAP was studied by high-resolution NMR. The almost complete backbone resonance assignment and partial side-chain assignment of the (2)H,(13)C,(15)N-labeled VSD were obtained for the protein domain solubilized in DPC/LDAO (2:1) mixed micelles. Secondary and tertiary structures of the VSD were characterized using secondary chemical shifts and NOE contacts. These data indicate that the spatial structure of the VSD solubilized in micelles corresponds to the structure of the domain in an open state of the channel. NOE contacts and secondary chemical shifts of amide protons indicate the presence of tightly bound water molecule as well as hydrogen bond formation involving an interhelical salt bridge (Asp62-R133) that stabilizes the overall structure of the domain. The backbone dynamics of the VSD was studied using (15)N relaxation measurements. The loop regions S1-S2 and S2-S3 were found mobile, while the S3-S4 loop (voltage-sensor paddle) was found stable at the ps-ns time scale. The moieties of S1, S2, S3, and S4 helices sharing interhelical contacts (at the level of the Asp62-R133 salt bridge) were observed in conformational exchange on the micros-ms time scale. Similar exchange-induced broadening of characteristic resonances was observed for the VSD solubilized in the membrane of lipid-protein nanodiscs composed of DMPC, DMPG, and POPC/DOPG lipids. Apparently, the observed interhelical motions represent an inherent property of the VSD of the KvAP channel and can play an important role in the voltage gating.

Heteronuclear NMR assignments and secondary structure of the coiled coil trimerization domain from cartilage matrix protein in oxidized and reduced forms.

PubMed Central

Wiltscheck, R.; Kammerer, R. A.; Dames, S. A.; Schulthess, T.; Blommers, M. J.; Engel, J.; Alexandrescu, A. T.

1997-01-01

The C-terminal oligomerization domain of chicken cartilage matrix protein is a trimeric coiled coil comprised of three identical 43-residue chains. NMR spectra of the protein show equivalent magnetic environments for each monomer, indicating a parallel coiled coil structure with complete threefold symmetry. Sequence-specific assignments for 1H-, 15N-, and 13C-NMR resonances have been obtained from 2D 1H NOESY and TOCSY spectra, and from 3D HNCA, 15N NOESY-HSQC, and HCCH-TOCSY spectra. A stretch of alpha-helix encompassing five heptad repeats (35 residues) has been identified from intra-chain HN-HN and HN-H alpha NOE connectivities. 3JHNH alpha coupling constants, and chemical shift indices. The alpha-helix begins immediately downstream of inter-chain disulfide bonds between residues Cys 5 and Cys 7, and extends to near the C-terminus of the molecule. The threefold symmetry of the molecule is maintained when the inter-chain disulfide bonds that flank the N-terminus of the coiled coil are reduced. Residues Ile 21 through Glu 36 show conserved chemical shifts and NOE connectivities, as well as strong protection from solvent exchange in the oxidized and reduced forms of the protein. By contrast, residues Ile 10 through Val 17 show pronounced chemical shift differences between the oxidized and reduced protein. Strong chemical exchange NOEs between HN resonances and water indicate solvent exchange on time scales faster than 10 s, and suggests a dynamic fraying of the N-terminus of the coiled coil upon reduction of the disulfide bonds. Possible roles for the disulfide crosslinks of the oligomerization domain in the function of cartilage matrix protein are proposed. PMID:9260286

Secondary Structures in Phe-Containing Isolated Dipeptide Chains: Laser Spectroscopy vs Quantum Chemistry.

PubMed

Loquais, Yohan; Gloaguen, Eric; Habka, Sana; Vaquero-Vara, Vanesa; Brenner, Valérie; Tardivel, Benjamin; Mons, Michel

2015-06-11

The intrinsic conformational landscape of two phenylalanine-containing protein chain models (-Gly-Phe- and -Ala-Phe- sequences) has been investigated theoretically and experimentally in the gas phase. The near UV spectroscopy (first ππ* transition of the Phe ring) is obtained experimentally under jet conditions where the conformational features can be resolved. Single-conformation IR spectroscopy in the NH stretch region is then obtained by IR/UV double resonance in the ground state, leading to resolved vibrational spectra that are assigned in terms of conformation and H-bonding content from comparison with quantum chemistry calculations. For the main conformer, whose UV spectrum exhibits a significant Franck-Condon activity in low frequency modes involving peptide backbone motions relative to the Phe chromophore, excited state IR spectroscopy has also been recorded in a UV/IR/UV experiment. The NH stretch spectral changes observed in such a ππ* labeling experiment enable us to determine those NH bonds that are coupled to the phenyl ring; they are compared to CC2 excited state calculations to quantify the geometry change upon ππ* excitation. The complete and consistent series of data obtained enable us to propose an unambiguous assignment for the gallery of conformers observed and to demonstrate that, in these two sequences, three conceptually important local structural motifs of proteins (β-strands, 27 ribbons, and β-turns) are represented. The satisfactory agreement between the experimental conformational distribution and the predicted landscape anticipated from the DFT-D approach demonstrates the capabilities of a theoretical method that accounts for dispersive interactions. It also shows that the flaws, inherent to a resonant two-photon ionization detection scheme, often evoked for aromatic chromophores, do not seem to be significant in the case of Phe.

MEMS-Based Force-Detected Nuclear Magnetic Resonance (FDNMR) Spectrometer

NASA Technical Reports Server (NTRS)

Lee, Choonsup; Butler, Mark C.; Elgammal, Ramez A.; George, Thomas; Hunt, Brian; Weitekamp, Daniel P.

2006-01-01

Nuclear Magnetic Resonance (NMR) spectroscopy allows assignment of molecular structure by acquiring the energy spectrum of nuclear spins in a molecule, and by interpreting the symmetry and positions of resonance lines in the spectrum. As such, NMR has become one of the most versatile and ubiquitous spectroscopic methods. Despite these tremendous successes, NMR experiments suffer from inherent low sensitivity due to the relatively low energy of photons in the radio frequency (rt) region of the electromagnetic spectrum. Here, we describe a high-resolution spectroscopy in samples with diameters in the micron range and below. We have reported design and fabrication of force-detected nuclear magnetic resonance (FDNMR).

Backbone dynamics of a model membrane protein: assignment of the carbonyl carbon /sup 13/C NMR resonances in detergent-solubilized M13 coat protein

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

Henry, G.D.; Weiner, J.H.; Sykes, B.D.

The major coat protein of the filamentous bacteriophage M13 is a 50-residue amphiphilic polypeptide which is inserted, as an integral membrane-spanning protein, in the inner membrane of the Escherichia coli host during infection. /sup 13/C was incorporated biosynthetically into a total of 23 of the peptide carbonyls using labeled amino acids (alanine, glycine, lysine, phenylalanine, and proline). The structure and dynamics of carbonyl-labeled M13 coat protein were monitored by /sup 13/C nuclear magnetic resonance (NMR) spectroscopy. Assignment of many resonances was achieved by using protease digestion, pH titration, or labeling of the peptide bond with both /sup 13/C and /supmore » 15/N. The carbonyl region of the natural-abundance /sup 13/C NMR spectrum of M13 coat protein in sodium dodecyl sulfate solution shows approximately eight backbone carbonyl resonances with line widths much narrower than the rest. Three of these more mobile residues correspond to assigned peaks (glycine-3, lysine-48, and alanine-49) in the individual amino acid spectra, and another almost certainly arises from glutamic acid-2. A ninth residue, alanine-1, also gives rise to a very narrow carbonyl resonance if the pH is well above or below the pK/sub a/ of the terminal amino group. These data suggest that only about four residues at either end of the protein experience large-amplitude spatial fluctuations; the rest of the molecule is essentially rigid on the time scale of the overall rotational tumbling of the protein-detergent complex. The relative exposure of different regions of detergent-bound protein was monitored by limited digestion with proteinase K. Comparable spectra and digestion patterns were obtained when the protein was solubilized in sodium deoxycholate, suggesting that the coat protein binds both amphiphiles in a similar fashion.« less

Observation of new even-parity states of Sm I by resonance ionization mass spectrometry

NASA Astrophysics Data System (ADS)

Jayasekharan, T.; Razvi, M. A. N.; Bhale, G. L.

1996-04-01

Resonance ionization mass spectrometry is applied to investigate high-lying even-parity states of Sm I. Eighty-six even-parity states of Sm I are discovered in the region 32950-36000 cm -1 . Absolute energies of these states are measured with an uncertainty of +/- 0.3 cm -1 , and total angular momenta are uniquely assigned for most of them.

An Evaluation of the Effects of an Oven Timer Study Behavior and Concurrent Completion and Accuracy of Assignments for a First Grade Repeater: A Case Study.

ERIC Educational Resources Information Center

Riegelman, Elizabeth D.; And Others

The effects of an oven timer as an antecedent stimulus on study behavior and concurrent completion and accuracy of reading and writing assignments were investigated for an 8-year-old first grade repeater who lacked motivation. Following baseline observations during which the teacher recorded study behavior and collected assignments with no…

(1)H, (13)C, (15)N backbone and side-chain resonance assignment of Nostoc sp. C139A variant of the heme-nitric oxide/oxygen binding (H-NOX) domain.

PubMed

Alexandropoulos, Ioannis I; Argyriou, Aikaterini I; Marousis, Kostas D; Topouzis, Stavros; Papapetropoulos, Andreas; Spyroulias, Georgios A

2016-10-01

The H-NOX (Heme-nitric oxide/oxygen binding) domain is conserved across eukaryotes and bacteria. In human soluble guanylyl cyclase (sGC) the H-NOX domain functions as a sensor for the gaseous signaling agent nitric oxide (NO). sGC contains the heme-binding H-NOX domain at its N-terminus, which regulates the catalytic site contained within the C-terminal end of the enzyme catalyzing the conversion of GTP (guanosine 5'-triphosphate) to GMP (guanylyl monophosphate). Here, we present the backbone and side-chain assignments of the (1)H, (13)C and (15)N resonances of the 183-residue H-NOX domain from Nostoc sp. through solution NMR.

Investigation of the thermonuclear 18Ne(α,p)21Na reaction rate via resonant elastic scattering of 21Na + p

NASA Astrophysics Data System (ADS)

Zhang, L. Y.; He, J. J.; Parikh, A.; Xu, S. W.; Yamaguchi, H.; Kahl, D.; Kubono, S.; Mohr, P.; Hu, J.; Ma, P.; Chen, S. Z.; Wakabayashi, Y.; Wang, H. W.; Tian, W. D.; Chen, R. F.; Guo, B.; Hashimoto, T.; Togano, Y.; Hayakawa, S.; Teranishi, T.; Iwasa, N.; Yamada, T.; Komatsubara, T.; Zhang, Y. H.; Zhou, X. H.

2014-01-01

The 18Ne(α,p)21Na reaction is thought to be one of the key breakout reactions from the hot CNO cycles to the rp process in type I x-ray bursts. In this work, the resonant properties of the compound nucleus 22Mg have been investigated by measuring the resonant elastic scattering of 21Na + p. An 89-MeV 21Na radioactive beam delivered from the CNS Radioactive Ion Beam Separator bombarded an 8.8 mg/cm2 thick polyethylene (CH2)n target. The 21Na beam intensity was about 2×105 pps, with a purity of about 70% on target. The recoiled protons were measured at the center-of-mass scattering angles of θc.m.≈175.2∘, 152.2∘, and 150.5∘ by three sets of ΔE-E telescopes, respectively. The excitation function was obtained with the thick-target method over energies Ex(22Mg)=5.5-9.2 MeV. In total, 23 states above the proton-threshold in 22Mg were observed, and their resonant parameters were determined via an R-matrix analysis of the excitation functions. We have made several new Jπ assignments and confirmed some tentative assignments made in previous work. The thermonuclear 18Ne(α,p)21Na rate has been recalculated based on our recommended spin-parity assignments. The astrophysical impact of our new rate has been investigated through one-zone postprocessing x-ray burst calculations. We find that the 18Ne(α,p)21Na rate significantly affects the peak nuclear energy generation rate, reaction fluxes, and onset temperature of this breakout reaction in these astrophysical phenomena.

A sequential assignment procedure for proteins that have intermediate line widths in MAS NMR spectra: amyloid fibrils of human CA150.WW2.

PubMed

Becker, Johanna; Ferguson, Neil; Flinders, Jeremy; van Rossum, Barth-Jan; Fersht, Alan R; Oschkinat, Hartmut

2008-08-11

The second WW domain (WW2) of CA150, a human transcriptional activator, forms amyloid fibrils in vitro under physiological conditions. Based on experimental constraints from MAS NMR spectroscopy experiments, alanine scanning and electron microscopy, a structural model of CA150.WW2 amyloid fibrils was calculated earlier. Here, the assignment strategy is presented and suggested as a general approach for proteins that show intermediate line width. The (13)C,(13)C correlation experiments were recorded on fully or partially (13)C-labelled fibrils. The earlier (13)C assignment (26 residues) was extended to 34 of the 40 residues by direct (13)C-excitation experiments by using a deuterated sample that showed strongly improved line width. A 3D HNC-TEDOR (transferred-echo double-resonance) experiment with deuterated CA150.WW2 fibrils yielded 14 amide nitrogen and proton resonance assignments. The obtained chemical shifts were compared with the chemical shifts determined with the natively folded WW domain. TALOS (Torsion angle likelihood obtained from shift and sequence similarity) predictions confirmed that, under physiological conditions, the fibrillar form of CA150.WW2 adopts a significantly different beta structure than the native WW-domain fold.

1H, 15N and 13C resonance assignments for free and IEEVD peptide-bound forms of the tetratricopeptide repeat domain from the human E3 ubiquitin ligase CHIP.

PubMed

Zhang, Huaqun; McGlone, Cameron; Mannion, Matthew M; Page, Richard C

2017-04-01

The ubiquitin ligase CHIP catalyzes covalent attachment of ubiquitin to unfolded proteins chaperoned by the heat shock proteins Hsp70/Hsc70 and Hsp90. CHIP interacts with Hsp70/Hsc70 and Hsp90 by binding of a C-terminal IEEVD motif found in Hsp70/Hsc70 and Hsp90 to the tetratricopeptide repeat (TPR) domain of CHIP. Although recruitment of heat shock proteins to CHIP via interaction with the CHIP-TPR domain is well established, alterations in structure and dynamics of CHIP upon binding are not well understood. In particular, the absence of a structure for CHIP-TPR in the free form presents a significant limitation upon studies seeking to rationally design inhibitors that may disrupt interactions between CHIP and heat shock proteins. Here we report the 1 H, 13 C, and 15 N backbone and side chain chemical shift assignments for CHIP-TPR in the free form, and backbone chemical shift assignments for CHIP-TPR in the IEEVD-bound form. The NMR resonance assignments will enable further studies examining the roles of dynamics and structure in regulating interactions between CHIP and the heat shock proteins Hsp70/Hsc70 and Hsp90.

Application of phase correction to improve the interpretation of crude oil spectra obtained using 7 T Fourier transform ion cyclotron resonance mass spectrometry.

PubMed

Cho, Yunju; Qi, Yulin; O'Connor, Peter B; Barrow, Mark P; Kim, Sunghwan

2014-01-01

In this study, a phase-correction technique was applied to the study of crude oil spectra obtained using a 7 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). 7 T FT-ICR MS had not been widely used for oil analysis due to the lower resolving power compared with high field FT-ICR MS. For low field instruments, usage of data that has not been phase-corrected results in an inability to resolve critical mass splits of C3 and SH4 (3.4 mDa), and (13)C and CH (4.5 mDa). This results in incorrect assignments of molecular formulae, and discontinuous double bond equivalents (DBE) and carbon number distributions of S1, S2, and hydrocarbon classes are obtained. Application of phase correction to the same data, however, improves the reliability of assignments and produces continuous DBE and carbon number distributions. Therefore, this study clearly demonstrates that phase correction improves data analysis and the reliability of assignments of molecular formulae in crude oil anlayses.

Opening complete band gaps in two dimensional locally resonant phononic crystals

NASA Astrophysics Data System (ADS)

Zhou, Xiaoling; Wang, Longqi

2018-05-01

Locally resonant phononic crystals (LRPCs) which have low frequency band gaps attract a growing attention in both scientific and engineering field recently. Wide complete locally resonant band gaps are the goal for researchers. In this paper, complete band gaps are achieved by carefully designing the geometrical properties of the inclusions in two dimensional LRPCs. The band structures and mechanisms of different types of models are investigated by the finite element method. The translational vibration patterns in both the in-plane and out-of-plane directions contribute to the full band gaps. The frequency response of the finite periodic structures demonstrate the attenuation effects in the complete band gaps. Moreover, it is found that the complete band gaps can be further widened and lowered by increasing the height of the inclusions. The tunable properties by changing the geometrical parameters provide a good way to open wide locally resonant band gaps.

Joint Experimental and Computational 17O and 1H Solid State NMR Study of Ba 2In 2O 4(OH) 2 Structure and Dynamics

DOE PAGES

Dervisoglu, Riza; Middlemiss, Derek S.; Blanc, Frederic; ...

2015-05-01

Here, a structural characterization of the hydrated form of the brownmillerite-type phase Ba 2In 2O 5, Ba 2In 2O 4(OH) 2, is reported using experimental multinuclear NMR spectroscopy and density functional theory (DFT) energy and GIPAW NMR calculations. When the oxygen ions from H 2O fill the inherent O vacancies of the brownmillerite structure, one of the water protons remains in the same layer (O3) while the second proton is located in the neighboring layer (O2) in sites with partial occupancies, as previously demonstrated by Jayaraman et al. (Solid State Ionics 2004, 170, 25–32) using X-ray and neutron studies. Calculationsmore » of possible proton arrangements within the partially occupied layer of Ba 2In 2O 4(OH) 2 yield a set of low energy structures; GIPAW NMR calculations on these configurations yield 1H and 17O chemical shifts and peak intensity ratios, which are then used to help assign the experimental MAS NMR spectra. Three distinct 1H resonances in a 2:1:1 ratio are obtained experimentally, the most intense resonance being assigned to the proton in the O3 layer. The two weaker signals are due to O2 layer protons, one set hydrogen bonding to the O3 layer and the other hydrogen bonding alternately toward the O3 and O1 layers. 1H magnetization exchange experiments reveal that all three resonances originate from protons in the same crystallographic phase, the protons exchanging with each other above approximately 150 °C. Three distinct types of oxygen atoms are evident from the DFT GIPAW calculations bare oxygens (O), oxygens directly bonded to a proton (H-donor O), and oxygen ions that are hydrogen bonded to a proton (H-acceptor O). The 17O calculated shifts and quadrupolar parameters are used to assign the experimental spectra, the assignments being confirmed by 1H– 17O double resonance experiments.« less

Joint Experimental and Computational 17O and 1H Solid State NMR Study of Ba2In2O4(OH)2 Structure and Dynamics.

PubMed

Dervişoğlu, Rıza; Middlemiss, Derek S; Blanc, Frédéric; Lee, Yueh-Lin; Morgan, Dane; Grey, Clare P

2015-06-09

A structural characterization of the hydrated form of the brownmillerite-type phase Ba 2 In 2 O 5 , Ba 2 In 2 O 4 (OH) 2 , is reported using experimental multinuclear NMR spectroscopy and density functional theory (DFT) energy and GIPAW NMR calculations. When the oxygen ions from H 2 O fill the inherent O vacancies of the brownmillerite structure, one of the water protons remains in the same layer (O3) while the second proton is located in the neighboring layer (O2) in sites with partial occupancies, as previously demonstrated by Jayaraman et al. (Solid State Ionics2004, 170, 25-32) using X-ray and neutron studies. Calculations of possible proton arrangements within the partially occupied layer of Ba 2 In 2 O 4 (OH) 2 yield a set of low energy structures; GIPAW NMR calculations on these configurations yield 1 H and 17 O chemical shifts and peak intensity ratios, which are then used to help assign the experimental MAS NMR spectra. Three distinct 1 H resonances in a 2:1:1 ratio are obtained experimentally, the most intense resonance being assigned to the proton in the O3 layer. The two weaker signals are due to O2 layer protons, one set hydrogen bonding to the O3 layer and the other hydrogen bonding alternately toward the O3 and O1 layers. 1 H magnetization exchange experiments reveal that all three resonances originate from protons in the same crystallographic phase, the protons exchanging with each other above approximately 150 °C. Three distinct types of oxygen atoms are evident from the DFT GIPAW calculations bare oxygens (O), oxygens directly bonded to a proton (H-donor O), and oxygen ions that are hydrogen bonded to a proton (H-acceptor O). The 17 O calculated shifts and quadrupolar parameters are used to assign the experimental spectra, the assignments being confirmed by 1 H- 17 O double resonance experiments.

Joint Experimental and Computational 17O and 1H Solid State NMR Study of Ba2In2O4(OH)2 Structure and Dynamics

PubMed Central

2015-01-01

A structural characterization of the hydrated form of the brownmillerite-type phase Ba2In2O5, Ba2In2O4(OH)2, is reported using experimental multinuclear NMR spectroscopy and density functional theory (DFT) energy and GIPAW NMR calculations. When the oxygen ions from H2O fill the inherent O vacancies of the brownmillerite structure, one of the water protons remains in the same layer (O3) while the second proton is located in the neighboring layer (O2) in sites with partial occupancies, as previously demonstrated by Jayaraman et al. (Solid State Ionics2004, 170, 25−32) using X-ray and neutron studies. Calculations of possible proton arrangements within the partially occupied layer of Ba2In2O4(OH)2 yield a set of low energy structures; GIPAW NMR calculations on these configurations yield 1H and 17O chemical shifts and peak intensity ratios, which are then used to help assign the experimental MAS NMR spectra. Three distinct 1H resonances in a 2:1:1 ratio are obtained experimentally, the most intense resonance being assigned to the proton in the O3 layer. The two weaker signals are due to O2 layer protons, one set hydrogen bonding to the O3 layer and the other hydrogen bonding alternately toward the O3 and O1 layers. 1H magnetization exchange experiments reveal that all three resonances originate from protons in the same crystallographic phase, the protons exchanging with each other above approximately 150 °C. Three distinct types of oxygen atoms are evident from the DFT GIPAW calculations bare oxygens (O), oxygens directly bonded to a proton (H-donor O), and oxygen ions that are hydrogen bonded to a proton (H-acceptor O). The 17O calculated shifts and quadrupolar parameters are used to assign the experimental spectra, the assignments being confirmed by 1H–17O double resonance experiments. PMID:26321789

Magnetic Resonance Spectroscopy for Evaluating the Effect of Pulsed Electromagnetic Fields on Marrow Adiposity in Postmenopausal Women With Osteopenia.

PubMed

Li, Shaojun; Jiang, Hongning; Wang, Bo; Gu, Mingjun; Bi, Xia; Yin, Ying; Wang, Yu

2018-06-12

Pulsed electromagnetic fields (PEMFs) could promote osteogenic differentiation and suppress adipogenic differentiation in bone mesenchymal stem cells ex vivo. However, data on the effect of PEMF on marrow adiposity in humans remain elusive. We aimed to determine the in vivo effect of PEMF on marrow adiposity in postmenopausal women using magnetic resonance spectroscopy. Sixty-one postmenopausal women with osteopenia, aged 53 to 85 years, were randomly assigned to receive either PEMF treatment or placebo. The session was performed 3 times per week for 6 months. All women received adequate dietary calcium and vitamin D. Bone mineral density (BMD) by dual-energy x-ray absorptiometry, vertebral marrow fat content by magnetic resonance spectroscopy, and serum biomarkers were evaluated before and after 6 months of treatment. A total of 27 (87.1%) and 25 (83.3%) women completed the treatment schedule in the PEMF and placebo groups, respectively. After the 6-month treatment, lumbar spine and hip BMD increased by 1.46% to 2.04%, serum bone-specific alkaline phosphatase increased by 3.23%, and C-terminal telopeptides of type 1 collagen decreased by 9.12% in the PEMF group (P < 0.05), whereas the mean percentage changes in BMD and serum biomarkers were not significant in the placebo group. Pulsed electromagnetic field treatment significantly reduced marrow fat fraction by 4.81%. The treatment difference between the 2 groups was -4.43% (95% confidence interval, -3.70% to -5.65%; P = 0.009). Pulsed electromagnetic field is an effective physiotherapy in postmenopausal women, and this effect may, at least in part, regulate the amount of fat within the bone marrow. Magnetic resonance spectroscopy may serve as a complementary imaging biomarker for monitoring response to therapy in osteoporosis.

Adsorption of 1- and 2-butylimidazoles at the copper/air and steel/air interfaces studied by sum frequency generation vibrational spectroscopy.

PubMed

Casford, Michael T L; Davies, Paul B

2012-07-24

The structure of thin films of 1- and 2-butylimidazoles adsorbed on copper and steel surfaces under air was examined using sum frequency generation (SFG) vibrational spectroscopy in the ppp and ssp polarizations. Additionally, the SFG spectra of both isomers were recorded at 55 °C at the liquid imidazole/air interface for reference. Complementary bulk infrared, reflection-absorption infrared spectroscopy (RAIRS), and Raman spectra of both imidazoles were recorded for assignment purposes. The SFG spectra in the C-H stretching region at the liquid/air interface are dominated by resonances from the methyl end group of the butyl side chain of the imidazoles, indicating that they are aligned parallel or closely parallel to the surface normal. These are also the most prominent features in the SFG spectra on copper and steel. In addition, both the ppp and ssp spectra on copper show resonances from the C-H stretching modes of the imidazole ring for both isomers. The ring C-H resonances are completely absent from the spectra on steel and at the liquid/air interface. The relative intensities of the SFG spectra can be interpreted as showing that, on copper, under air, both butylimidazoles are adsorbed with their butyl side chains perpendicular to the interface and with the ring significantly inclined away from the surface plane and toward the surface normal. The SFG spectra of both imidazoles on steel indicate an orientation where the imidazole rings are parallel or nearly parallel to the surface. The weak C-H resonances from the ring at the liquid/air interface suggest that the tilt angle of the ring from the surface normal at this interface is significantly greater than it is on copper.

The 700-1500 cm{sup −1} region of the S{sub 1} (A{sup ~1}B{sub 2}) state of toluene studied with resonance-enhanced multiphoton ionization (REMPI), zero-kinetic-energy (ZEKE) spectroscopy, and time-resolved slow-electron velocity-map imaging (tr-SEVI) spectroscopy

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

Gardner, Adrian M.; Green, Alistair M.; Tamé-Reyes, Victor M.

We report (nanosecond) resonance-enhanced multiphoton ionization (REMPI), (nanosecond) zero-kinetic-energy (ZEKE) and (picosecond) time-resolved slow-electron velocity map imaging (tr-SEVI) spectra of fully hydrogenated toluene (Tol-h{sub 8}) and the deuterated-methyl group isotopologue (α{sub 3}-Tol-d{sub 3}). Vibrational assignments are made making use of the activity observed in the ZEKE and tr-SEVI spectra, together with the results from quantum chemical and previous experimental results. Here, we examine the 700–1500 cm{sup −1} region of the REMPI spectrum, extending our previous work on the region ≤700 cm{sup −1}. We provide assignments for the majority of the S{sub 1} and cation bands observed, and in particular wemore » gain insight regarding a number of regions where vibrations are coupled via Fermi resonance. We also gain insight into intramolecular vibrational redistribution in this molecule.« less

A simple resonance enhanced laser ionization scheme for CO via the A1Π state

NASA Astrophysics Data System (ADS)

Sun, Z. F.; von Zastrow, A. D.; Parker, D. H.

2017-07-01

We investigate the laser ionization process taking place when the CO molecule is exposed to vacuum ultraviolet (VUV) radiation resonant with the CO A1Π (v = 0) ← X1Σ+ (v = 0) transition around 154 nm, along with the ultraviolet (UV) and visible (Red) radiation used to generate VUV by four-wave difference-frequency mixing. By measuring the CO+ ion recoil and a room temperature gas spectrum, it is possible to assign the ionization process as 1 + 1' + 1'' REMPI where the one-photon steps refer to the VUV, UV, and Red radiation, respectively. Resonance enhanced ionization of rotational states around J = 12 arise due to the overlap of the fixed wavelength UV (˜250 nm) with the R band-head of a transition assigned to CO E1Π (v = 6) ← A1Π (v = 0) with a term value of 104 787.5 cm-1. The REMPI process is efficient and polarization sensitive and should be useful in a wide range of studies involving nascent CO.

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

Fischer, Sean A.; Ueltschi, Tyler W.; El-Khoury, Patrick Z.

Carbon-hydrogen (C-H) vibration modes serve as key probes in the chemical identification of hydrocarbons and in vibrational sum-frequency generation (SFG) spectroscopy of hydrocarbons at the liquid/gas interface. Their assignments pose a challenge from a theoretical viewpoint. Here in this work, we present a detailed study of the C-H stretching region of dimethyl sulfoxide (DMSO) using a new Gaussian basis set- based ab initio molecular dynamics (AIMD) module that we have implemented in the NWChem computational chemistry program. By combining AIMD simulations and static normal mode analysis, we interpret experimental infrared and Raman spectra and explore the role of anharmonic effectsmore » in this system. Our anharmonic normal mode analysis of the in-phase and out-of-phase symmetric C-H stretching modes challenges the previous experimental assignment of the shoulder in the symmetric C-H stretching peak as an overtone or Fermi resonance. In addition, our AIMD simulations also show significant broadening of the in-phase symmetric C-H stretching resonance, which suggests that the experimentally observed shoulder is due to thermal broadening of the symmetric stretching resonance.« less

The Effect of Online Chapter Quizzes on Exam Performance in an Undergraduate Social Psychology Course

PubMed Central

Johnson, Bethany C.; Kiviniemi, Marc T.

2009-01-01

Assigned textbook readings are a common requirement in undergraduate courses, but students often do not complete reading assignments or do not do so until immediately before an exam. This may have detrimental effects on learning and course performance. Regularly scheduled quizzes on reading material may increase completion of reading assignments and therefore course performance. This study examined the effectiveness of compulsory, mastery-based, weekly reading quizzes as a means of improving exam and course performance. Completion of reading quizzes was related to both better exam and course performance. The discussion includes recommendations for the use of quizzes in undergraduate courses. PMID:20046908

The Omaha System as a Structured Instrument for Bridging Nursing Informatics With Public Health Nursing Education: A Feasibility Study.

PubMed

Eardley, Debra L; Krumwiede, Kelly A; Secginli, Selda; Garner, Linda; DeBlieck, Conni; Cosansu, Gulhan; Nahcivan, Nursen O

2018-06-01

Advancements in healthcare systems include adoption of health information technology to ensure healthcare quality. Educators are challenged to determine strategies to integrate health information technology into nursing curricula for building a nursing workforce competent with electronic health records, standardized terminology, evidence-based practice, and evaluation. Nursing informatics, a growing specialty field, comprises health information technology relative to the profession of nursing. It is essential to integrate nursing informatics across nursing curricula to effectively position competent graduates in technology-laden healthcare environments. Nurse scholars developed and evaluated a nursing informatics case study assignment used in undergraduate level public health nursing courses. The assignment included an unfolding scenario followed by electronic health record charting using standardized terminology to guide the nursing process. The assignment was delivered either online or in class. Seventy-two undergraduate students completed the assignment and a posttest. Fifty-one students completed a satisfaction survey. Results indicated that students who completed the assignment online demonstrated a higher level of content mastery than those who completed the assignment in class. Content mastery was based on posttest results, which evaluated students' electronic health record charting for the nursing assessment, evidence-based interventions, and evaluations. This innovative approach may be valuable to educators in response to the National Academy of Sciences recommendations for healthcare education reform.

1H, 13C, and 15N resonance assignments of an enzymatically active domain from the catalytic component (CDTa, residues 216-420) of a binary toxin from Clostridium difficile.

PubMed

Roth, Braden M; Godoy-Ruiz, Raquel; Varney, Kristen M; Rustandi, Richard R; Weber, David J

2016-04-01

Clostridium difficile is a bacterial pathogen and is the most commonly reported source of nosocomial infection in industrialized nations. Symptoms of C. difficile infection (CDI) include antibiotic-associated diarrhea, pseudomembranous colitis, sepsis and death. Over the last decade, rates and severity of hospital infections in North America and Europe have increased dramatically and correlate with the emergence of a hypervirulent strain of C. difficile characterized by the presence of a binary toxin, CDT (C. difficile toxin). The binary toxin consists of an enzymatic component (CDTa) and a cellular binding component (CDTb) that together form the active binary toxin complex. CDTa harbors a pair of structurally similar but functionally distinct domains, an N-terminal domain (residues 1-215; (1-215)CDTa) that interacts with CDTb and a C-terminal domain (residues 216-420; (216-420)CDTa) that harbors the intact ADP-ribosyltransferase (ART) active site. Reported here are the (1)H, (13)C, and (15)N backbone resonance assignments of the 23 kDa, 205 amino acid C-terminal enzymatic domain of CDTa, termed (216-420)CDTa. These NMR resonance assignments for (216-420)CDTa represent the first for a family of ART binary toxins and provide the framework for detailed characterization of the solution-state protein structure determination, dynamic studies of this domain, as well as NMR-based drug discovery efforts.

Exploring the Contribution of Extra Credit in Marketing Education

ERIC Educational Resources Information Center

Elbeck, Matt; DeLong, Deborah

2015-01-01

This study advances the literature on the incidence, attitudes and motivations to complete extra credit assignments. Behavioral feedback from 59 marketing instructors and 43 Principles of Marketing students aligned with reported incidence rates of offering and completing extra credit assignments, respectively. This was followed with open-ended…

CP/MAS /sup 13/C NMR spectroscopic study of chlorophyll a in the solid state

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

Brown, C.E.; Spencer, R.B.; Burger, V.T.

1983-09-01

Solid-state cross-polarization, magic-angle sample spinning carbon-13 nuclear magnetic resonance spectra have been recorded on chlorophyll a- water aggregates, methyl pyrochlorophyllide a and methyl pyropheophorbide a (derivatives that lack a phytyl chain). Spectra have also been collected under a decoupling regime in which resonances of certain hydrogen-bearing carbon atoms are suppressed. These observations are used to assign the solid state spectra.

Structural Characterization of Polymer-Clay Nanocomposites Prepared by Co-Precipitation Using EPR Techniques

PubMed Central

Kielmann, Udo; Jeschke, Gunnar; García-Rubio, Inés

2014-01-01

Polymer-clay nanocomposites (PCNCs) containing either a rubber or an acrylate polymer were prepared by drying or co-precipitating polymer latex and nanolayered clay (synthetic and natural) suspensions. The interface between the polymer and the clay nanoparticles was studied by electron paramagnetic resonance (EPR) techniques by selectively addressing spin probes either to the surfactant layer (labeled stearic acid) or the clay surface (labeled catamine). Continuous-wave (CW) EPR studies of the surfactant dynamics allow to define a transition temperature T* which was tentatively assigned to the order-disorder transition of the surfactant layer. CW EPR studies of PCNC showed that completely exfoliated nanoparticles coexist with agglomerates. HYSCORE spectroscopy in PCNCs showed couplings within the probe −assigned with DFT computations− and couplings with nuclei of the environment, 1H and 23Na for the surfactant layer probe, and 29Si, 7Li, 19F and 23Na for the clay surface probe. Analysis of these couplings indicates that the integrity of the surfactant layer is conserved and that there are sizeable ionic regions containing sodium ions directly beyond the surfactant layer. Simulations of the very weak couplings demonstrated that the HYSCORE spectra are sensitive to the composition of the clay and whether or not clay platelets stack. PMID:28788520

Quantitative, equal carbon response HSQC experiment, QEC-HSQC

NASA Astrophysics Data System (ADS)

Mäkelä, Valtteri; Helminen, Jussi; Kilpeläinen, Ilkka; Heikkinen, Sami

2016-10-01

Quantitative NMR has become increasingly useful and popular in recent years, with many new and emerging applications in metabolomics, quality control, reaction monitoring and other types of mixture analysis. While sensitive and simple to acquire, the low resolving power of 1D 1H NMR spectra can be a limiting factor when analyzing complex mixtures. This drawback can be solved by observing a different type of nuclei offering improved resolution or with multidimensional experiments, such as HSQC. In this paper, we present a novel Quantitative, Equal Carbon HSQC (QEC-HSQC) experiment providing an equal response across different type of carbons regardless of the number of attached protons, in addition to an uniform response over a wide range of 1JCH couplings. This enables rapid quantification and integration over multiple signals without the need for complete resonance assignments and simplifies the integration of overlapping signals.

Optimization and automation of quantitative NMR data extraction.

PubMed

Bernstein, Michael A; Sýkora, Stan; Peng, Chen; Barba, Agustín; Cobas, Carlos

2013-06-18

NMR is routinely used to quantitate chemical species. The necessary experimental procedures to acquire quantitative data are well-known, but relatively little attention has been applied to data processing and analysis. We describe here a robust expert system that can be used to automatically choose the best signals in a sample for overall concentration determination and determine analyte concentration using all accepted methods. The algorithm is based on the complete deconvolution of the spectrum which makes it tolerant of cases where signals are very close to one another and includes robust methods for the automatic classification of NMR resonances and molecule-to-spectrum multiplets assignments. With the functionality in place and optimized, it is then a relatively simple matter to apply the same workflow to data in a fully automatic way. The procedure is desirable for both its inherent performance and applicability to NMR data acquired for very large sample sets.

Conformation and Complexation of Tannins: NMR Spectra and Molecular Search Modeling of Flavan-3-ols

Treesearch

Richard W. Hemingway; Fred L. Tohiason; G. Wayne McGraw; Jan P. Steynberg

1996-01-01

Studies offlavan-3-01sin their biologically significant phenolic form show that both H-6 and C-6 resonances are downfield from H-8 and C-8. Therefore, assignments for the H atoms of the A-ring are inverse to those commonly reported. By contrast, in the methyl ether and methyl ether acetate derivatives, both H-8 and C-8 are downfield from H-6 and C-6 and assignments...

PICKY: a novel SVD-based NMR spectra peak picking method.

PubMed

Alipanahi, Babak; Gao, Xin; Karakoc, Emre; Donaldson, Logan; Li, Ming

2009-06-15

Picking peaks from experimental NMR spectra is a key unsolved problem for automated NMR protein structure determination. Such a process is a prerequisite for resonance assignment, nuclear overhauser enhancement (NOE) distance restraint assignment, and structure calculation tasks. Manual or semi-automatic peak picking, which is currently the prominent way used in NMR labs, is tedious, time consuming and costly. We introduce new ideas, including noise-level estimation, component forming and sub-division, singular value decomposition (SVD)-based peak picking and peak pruning and refinement. PICKY is developed as an automated peak picking method. Different from the previous research on peak picking, we provide a systematic study of the proposed method. PICKY is tested on 32 real 2D and 3D spectra of eight target proteins, and achieves an average of 88% recall and 74% precision. PICKY is efficient. It takes PICKY on average 15.7 s to process an NMR spectrum. More important than these numbers, PICKY actually works in practice. We feed peak lists generated by PICKY to IPASS for resonance assignment, feed IPASS assignment to SPARTA for fragments generation, and feed SPARTA fragments to FALCON for structure calculation. This results in high-resolution structures of several proteins, for example, TM1112, at 1.25 A. PICKY is available upon request. The peak lists of PICKY can be easily loaded by SPARKY to enable a better interactive strategy for rapid peak picking.

Reduced dimensionality (3,2)D NMR experiments and their automated analysis: implications to high-throughput structural studies on proteins.

PubMed

Reddy, Jithender G; Kumar, Dinesh; Hosur, Ramakrishna V

2015-02-01

Protein NMR spectroscopy has expanded dramatically over the last decade into a powerful tool for the study of their structure, dynamics, and interactions. The primary requirement for all such investigations is sequence-specific resonance assignment. The demand now is to obtain this information as rapidly as possible and in all types of protein systems, stable/unstable, soluble/insoluble, small/big, structured/unstructured, and so on. In this context, we introduce here two reduced dimensionality experiments – (3,2)D-hNCOcanH and (3,2)D-hNcoCAnH – which enhance the previously described 2D NMR-based assignment methods quite significantly. Both the experiments can be recorded in just about 2-3 h each and hence would be of immense value for high-throughput structural proteomics and drug discovery research. The applicability of the method has been demonstrated using alpha-helical bovine apo calbindin-D9k P43M mutant (75 aa) protein. Automated assignment of this data using AUTOBA has been presented, which enhances the utility of these experiments. The backbone resonance assignments so derived are utilized to estimate secondary structures and the backbone fold using Web-based algorithms. Taken together, we believe that the method and the protocol proposed here can be used for routine high-throughput structural studies of proteins. Copyright © 2014 John Wiley & Sons, Ltd.

Simple and robust referencing system enables identification of dissolved-phase xenon spectral frequencies.

PubMed

Antonacci, Michael A; Zhang, Le; Burant, Alex; McCallister, Drew; Branca, Rosa T

2018-08-01

To assess the effect of macroscopic susceptibility gradients on the gas-phase referenced dissolved-phase 129 Xe (DPXe) chemical shift (CS) and to establish the robustness of a water-based referencing system for in vivo DPXe spectra. Frequency shifts induced by spatially varying magnetic susceptibility are calculated by finite-element analysis for the human head and chest. Their effect on traditional gas-phase referenced DPXe CS is then assessed theoretically and experimentally. A water-based referencing system for the DPXe resonances that uses the local water protons as reference is proposed and demonstrated in vivo in rats. Across the human brain, macroscopic susceptibility gradients can induce an apparent variation in the DPXe CS of up to 2.5 ppm. An additional frequency shift as large as 6.5 ppm can exist between DPXe and gas-phase resonances. By using nearby water protons as reference for the DPXe CS, the effect of macroscopic susceptibility gradients is eliminated and consistent CS values are obtained in vivo, regardless of shimming conditions, region of interest analyzed, animal orientation, or lung inflation. Combining in vitro and in vivo spectroscopic measurements finally enables confident assignment of some of the DPXe peaks observed in vivo. To use hyperpolarized xenon as a biological probe in tissues, the DPXe CS in specific organs/tissues must be reliably measured. When the gas-phase is used as reference, variable CS values are obtained for DPXe resonances. Reliable peak assignments in DPXe spectra can be obtained by using local water protons as reference. Magn Reson Med 80:431-441, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Vibrational spectroscopic studies of Isoleucine by quantum chemical calculations.

PubMed

Moorthi, P P; Gunasekaran, S; Ramkumaar, G R

2014-04-24

In this work, we reported a combined experimental and theoretical study on molecular structure, vibrational spectra and NBO analysis of Isoleucine (2-Amino-3-methylpentanoic acid). The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments, thermodynamics properties, NBO analyses, NMR chemical shifts and ultraviolet-visible spectral interpretation of Isoleucine have been studied by performing MP2 and DFT/cc-pVDZ level of theory. The FTIR, FT-Raman spectra were recorded in the region 4000-400 cm(-1) and 3500-50 cm(-1) respectively. The UV-visible absorption spectra of the compound were recorded in the range of 200-800 nm. Computational calculations at MP2 and B3LYP level with basis set of cc-pVDZ is employed in complete assignments of Isoleucine molecule on the basis of the potential energy distribution (PED) of the vibrational modes, calculated using VEDA-4 program. The calculated wavenumbers are compared with the experimental values. The difference between the observed and calculated wavenumber values of most of the fundamentals is very small. (13)C and (1)H nuclear magnetic resonance chemical shifts of the molecule were calculated using the gauge independent atomic orbital (GIAO) method and compared with experimental results. The formation of hydrogen bond was investigated in terms of the charge density by the NBO calculations. Based on the UV spectra and TD-DFT calculations, the electronic structure and the assignments of the absorption bands were carried out. Besides, molecular electrostatic potential (MEP) were investigated using theoretical calculations. Copyright © 2014 Elsevier B.V. All rights reserved.

Zero kinetic energy photoelectron spectroscopy of triphenylene.

PubMed

Harthcock, Colin; Zhang, Jie; Kong, Wei

2014-06-28

We report vibrational information of both the first electronically excited state and the ground cationic state of jet-cooled triphenylene via the techniques of resonantly enhanced multiphoton ionization (REMPI) and zero kinetic energy (ZEKE) photoelectron spectroscopy. The first excited electronic state S1 of the neutral molecule is of A1' symmetry and is therefore electric dipole forbidden in the D3h group. Consequently, there are no observable Franck-Condon allowed totally symmetric a1' vibrational bands in the REMPI spectrum. All observed vibrational transitions are due to Herzberg-Teller vibronic coupling to the E' third electronically excited state S3. The assignment of all vibrational bands as e' symmetry is based on comparisons with calculations using the time dependent density functional theory and spectroscopic simulations. When an electron is eliminated, the molecular frame undergoes Jahn-Teller distortion, lowering the point group to C2v and resulting in two nearly degenerate electronic states of A2 and B1 symmetry. Here we follow a crude treatment by assuming that all e' vibrational modes resolve into b2 and a1 modes in the C2v molecular frame. Some observed ZEKE transitions are tentatively assigned, and the adiabatic ionization threshold is determined to be 63 365 ± 7 cm(-1). The observed ZEKE spectra contain a consistent pattern, with a cluster of transitions centered near the same vibrational level of the cation as that of the intermediate state, roughly consistent with the propensity rule. However, complete assignment of the detailed vibrational structure due to Jahn-Teller coupling requires much more extensive calculations, which will be performed in the future.

Automated sequence-specific protein NMR assignment using the memetic algorithm MATCH.

PubMed

Volk, Jochen; Herrmann, Torsten; Wüthrich, Kurt

2008-07-01

MATCH (Memetic Algorithm and Combinatorial Optimization Heuristics) is a new memetic algorithm for automated sequence-specific polypeptide backbone NMR assignment of proteins. MATCH employs local optimization for tracing partial sequence-specific assignments within a global, population-based search environment, where the simultaneous application of local and global optimization heuristics guarantees high efficiency and robustness. MATCH thus makes combined use of the two predominant concepts in use for automated NMR assignment of proteins. Dynamic transition and inherent mutation are new techniques that enable automatic adaptation to variable quality of the experimental input data. The concept of dynamic transition is incorporated in all major building blocks of the algorithm, where it enables switching between local and global optimization heuristics at any time during the assignment process. Inherent mutation restricts the intrinsically required randomness of the evolutionary algorithm to those regions of the conformation space that are compatible with the experimental input data. Using intact and artificially deteriorated APSY-NMR input data of proteins, MATCH performed sequence-specific resonance assignment with high efficiency and robustness.

Suppressing the crosstalk between racetrack resonators by grating assisted couplers for WDM sensing

NASA Astrophysics Data System (ADS)

Zhang, Xuezhi; Jiang, Junfeng; Liu, Kun; Yu, Zhe; Feng, Ming; Chen, Wenjie; Liu, Tiegen

2017-12-01

We proposed a uniform racetrack resonators based sensor for bio-chemical WDM sensing. The sensing channels are assigned by grating assisted contra-directional couplers. Each resonator only occupies one sensing channel. The crosstalk between sensing channels can be suppressed by aligning the center coupling wavelength of one resonator with the weak coupling wavelength of the others. Based on the simulation results obtained from transfer matrix method, the sensing channel gap can be reduced down to 2 FSRs (˜1.5 nm) of the resonator. The total crosstalk can be as low as 2.5 × 10-2 dB in a sensor with 23 channels covering the whole C band. This sensor with high throughput will be very important for analyzing a wide range of analytes, such as organic compounds or biological materials.

Exogenous spatial attention influences figure-ground assignment.

PubMed

Vecera, Shaun P; Flevaris, Anastasia V; Filapek, Joseph C

2004-01-01

In a hierarchical stage account of vision, figure-ground assignment is thought to be completed before the operation of focal spatial attention. Results of previous studies have supported this account by showing that unpredictive, exogenous spatial precues do not influence figure-ground assignment, although voluntary attention can influence figure-ground assignment. However, in these studies, attention was not summoned directly to a region in a figure-ground display. In three experiments, we addressed the relationship between figure-ground assignment and visuospatial attention. In Experiment 1, we replicated the finding that exogenous precues do not influence figure-ground assignment when they direct attention outside of a figure-ground stimulus. In Experiment 2, we demonstrated that exogenous attention can influence figure-ground assignment if it is directed to one of the regions in a figure-ground stimulus. In Experiment 3, we demonstrated that exogenous attention can influence figure-ground assignment in displays that contain a Gestalt figure-ground cue; this result suggests that figure-ground processes are not entirely completed prior to the operation of focal spatial attention. Exogenous spatial attention acts as a cue for figure-ground assignment and can affect the outcome of figure-ground processes.

Metallated DNA Aptamers for Prostate Cancer Treatment

DTIC Science & Technology

2013-03-01

minor groove while the new 320 nm maxima reflect the binding of N-methyl pyrrole moieties of netropsin in the minor groove of 3’FdU.(Zimmer, Marck...resonance assignment and those consistent with the pyrrole 1 H resonances of netropsin (Fig. 3). NOESY crosspeaks from FdU imino 1 H to putative...computational chemistry data from our laboratory and with netropsin binding in the minor groove based upon NOE data from pyrrole 1 H of netropsin and

Assigning the NMR Spectrum of Glycidol: An Advanced Organic Chemistry Exercise

ERIC Educational Resources Information Center

Helms, Eric; Arpaia, Nicholas; Widener, Melissa

2007-01-01

Various one- and two-dimensional NMR experiments have been found to be extremely useful for assigning the proton and carbon NMR spectra of glycidol. The technique provides extremely valuable information aiding in the complete assignment of the peaks.

NMR 1H,13C, 15N backbone and 13C side chain resonance assignment of the G12C mutant of human K-Ras bound to GDP.

PubMed

Sharma, Alok K; Lee, Seung-Joo; Rigby, Alan C; Townson, Sharon A

2018-05-02

K-Ras is a key driver of oncogenesis, accounting for approximately 80% of Ras-driven human cancers. The small GTPase cycles between an inactive, GDP-bound and an active, GTP-bound state, regulated by guanine nucleotide exchange factors and GTPase activating proteins, respectively. Activated K-Ras regulates cell proliferation, differentiation and survival by signaling through several effector pathways, including Raf-MAPK. Oncogenic mutations that impair the GTPase activity of K-Ras result in a hyperactivated state, leading to uncontrolled cellular proliferation and tumorogenesis. A cysteine mutation at glycine 12 is commonly found in K-Ras associated cancers, and has become a recent focus for therapeutic intervention. We report here 1 H N, 15 N, and 13 C resonance assignments for the 19.3 kDa (aa 1-169) human K-Ras protein harboring an oncogenic G12C mutation in the GDP-bound form (K-RAS G12C-GDP ), using heteronuclear, multidimensional NMR spectroscopy. Backbone 1 H- 15 N correlations have been assigned for all non-proline residues, except for the first methionine residue.

Fingerprinting redox and ligand states in haemprotein crystal structures using resonance Raman spectroscopy.

PubMed

Kekilli, Demet; Dworkowski, Florian S N; Pompidor, Guillaume; Fuchs, Martin R; Andrew, Colin R; Antonyuk, Svetlana; Strange, Richard W; Eady, Robert R; Hasnain, S Samar; Hough, Michael A

2014-05-01

It is crucial to assign the correct redox and ligand states to crystal structures of proteins with an active redox centre to gain valid functional information and prevent the misinterpretation of structures. Single-crystal spectroscopies, particularly when applied in situ at macromolecular crystallography beamlines, allow spectroscopic investigations of redox and ligand states and the identification of reaction intermediates in protein crystals during the collection of structural data. Single-crystal resonance Raman spectroscopy was carried out in combination with macromolecular crystallography on Swiss Light Source beamline X10SA using cytochrome c' from Alcaligenes xylosoxidans. This allowed the fingerprinting and validation of different redox and ligand states, identification of vibrational modes and identification of intermediates together with monitoring of radiation-induced changes. This combined approach provides a powerful tool to obtain complementary data and correctly assign the true oxidation and ligand state(s) in redox-protein crystals.

An efficient randomized algorithm for contact-based NMR backbone resonance assignment.

PubMed

Kamisetty, Hetunandan; Bailey-Kellogg, Chris; Pandurangan, Gopal

2006-01-15

Backbone resonance assignment is a critical bottleneck in studies of protein structure, dynamics and interactions by nuclear magnetic resonance (NMR) spectroscopy. A minimalist approach to assignment, which we call 'contact-based', seeks to dramatically reduce experimental time and expense by replacing the standard suite of through-bond experiments with the through-space (nuclear Overhauser enhancement spectroscopy, NOESY) experiment. In the contact-based approach, spectral data are represented in a graph with vertices for putative residues (of unknown relation to the primary sequence) and edges for hypothesized NOESY interactions, such that observed spectral peaks could be explained if the residues were 'close enough'. Due to experimental ambiguity, several incorrect edges can be hypothesized for each spectral peak. An assignment is derived by identifying consistent patterns of edges (e.g. for alpha-helices and beta-sheets) within a graph and by mapping the vertices to the primary sequence. The key algorithmic challenge is to be able to uncover these patterns even when they are obscured by significant noise. This paper develops, analyzes and applies a novel algorithm for the identification of polytopes representing consistent patterns of edges in a corrupted NOESY graph. Our randomized algorithm aggregates simplices into polytopes and fixes inconsistencies with simple local modifications, called rotations, that maintain most of the structure already uncovered. In characterizing the effects of experimental noise, we employ an NMR-specific random graph model in proving that our algorithm gives optimal performance in expected polynomial time, even when the input graph is significantly corrupted. We confirm this analysis in simulation studies with graphs corrupted by up to 500% noise. Finally, we demonstrate the practical application of the algorithm on several experimental beta-sheet datasets. Our approach is able to eliminate a large majority of noise edges and to uncover large consistent sets of interactions. Our algorithm has been implemented in the platform-independent Python code. The software can be freely obtained for academic use by request from the authors.

What Keeps Chinese Students Motivated in Doing Math Homework? An Empirical Investigation

ERIC Educational Resources Information Center

Yang, Fuyi; Xu, Jianzhong; Tan, Heping; Liang, Ningjian

2016-01-01

Background: As many students face the enduring challenge of maintaining their motivation to complete homework assignments, there is a critical need to pay close attention to homework motivation management (i.e., students' efforts to sustain or enhance their motivation in order to complete homework assignments that might be boring or difficult).…

Infrared and Raman Spectroscopy from Ab Initio Molecular Dynamics and Static Normal Mode Analysis: The C–H Region of DMSO as a Case Study

DOE PAGES

Fischer, Sean A.; Ueltschi, Tyler W.; El-Khoury, Patrick Z.; ...

2015-07-29

Carbon-hydrogen (C-H) vibration modes serve as key probes in the chemical identification of hydrocarbons and in vibrational sum-frequency generation (SFG) spectroscopy of hydrocarbons at the liquid/gas interface. Their assignments pose a challenge from a theoretical viewpoint. Here in this work, we present a detailed study of the C-H stretching region of dimethyl sulfoxide (DMSO) using a new Gaussian basis set- based ab initio molecular dynamics (AIMD) module that we have implemented in the NWChem computational chemistry program. By combining AIMD simulations and static normal mode analysis, we interpret experimental infrared and Raman spectra and explore the role of anharmonic effectsmore » in this system. Our anharmonic normal mode analysis of the in-phase and out-of-phase symmetric C-H stretching modes challenges the previous experimental assignment of the shoulder in the symmetric C-H stretching peak as an overtone or Fermi resonance. In addition, our AIMD simulations also show significant broadening of the in-phase symmetric C-H stretching resonance, which suggests that the experimentally observed shoulder is due to thermal broadening of the symmetric stretching resonance.« less

Proton nuclear magnetic resonance characterization of the aromatic residues in the variant-3 neurotoxin from Centruroides sculpturatus Ewing

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

Krishna, N.R.; Nettesheim, D.G.; Klevit, R.E.

1989-02-21

The amino acid sequence for the variant-3 (CsE-v3) toxin from the venom of the scorpion Centruroides sculpturatus Ewing contains eight aromatic residues. By use of 2D NMR spectroscopic methods, the resonances from the individual protons (NH, C{sup alpha}H, C{sup beta}H{prime}, H{double prime}, and the ring) for each of the individual aromatic residues have been completely assigned. The spatial arrangement of the aromatic ring systems with respect to each other has been qualitatively analyzed by 2D-NOESY techniques. The results show that Trp-47, Tyr-4, and Tyr-42 are in close spatial proximity to each other. The NOESY contacts and the ring current inducedmore » shifts in the resonances of the individual protons of Tyr-4 and Trp-47 suggest that the aromatic ring planes of these residues are in an orthogonal arrangement. A comparison with the published crystal structure suggests that there is a minor rearrangement of the aromatic rings in the solution phase. No 2D-NOESY contacts involving Phe-44 and Tyr-14 to any other aromatic ring protons have been observed. The pH dependence of the aromatic ring proton chemical shifts has also been studied. These results suggest that the Tyr-58 phenolic group is experiencing a hydrogen-bonding interaction with a positively charged group, while Tyr-4, -14, -38, and -40 are experiencing through-space interactions with proximal negatively charged groups. These studies define the microenvironment of the aromatic residues in the variant-3 neurotoxin in aqueous solution.« less

Targeting TMPRSS2 ERG in Prostate Cancer

DTIC Science & Technology

2016-09-01

Assay development for surface Plasmon resonance with purified ERG protein (months 31-36, completed July 2016) 7c. Perform thermal shift and...surface Plasmon resonance on compounds and determine binding constants (months 37-42, completed July 2016) Task 8. Identify FDA approved drugs that

Measuring Conceptual Gains and Benefits of Student Problem Designs

NASA Astrophysics Data System (ADS)

Mandell, Eric; Snyder, Rachel; Oswald, Wayne

2011-10-01

Writing assignments can be an effective way of getting students to practice higher-order learning skills in physics. One example of such an assignment is that of problem design. One version of the problem design assignment asks the student to evaluate the material from a chapter, after all instruction and other activities are complete. The student is to decide what concepts and ideas are most central, or critical in the chapter, and construct a problem that he or she feels best encompasses the major themes. Here, we use two concept surveys (FCI and EMCS) to measure conceptual gains for students completing the problem design assignment and present the preliminary results, comparing across several categories including gender, age, degree program, and class standing.

SUGGEL: A Program Suggesting the Orbital Angular Momentum of a Neutron Resonance from the Magnitude of its Neutron Width

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

Oh, S.Y.

2001-02-02

The SUGGEL computer code has been developed to suggest a value for the orbital angular momentum of a neutron resonance that is consistent with the magnitude of its neutron width. The suggestion is based on the probability that a resonance having a certain value of g{Gamma}{sub n} is an l-wave resonance. The probability is calculated by using Bayes' theorem on the conditional probability. The probability density functions (pdf's) of g{Gamma}{sub n} for up to d-wave (l=2) have been derived from the {chi}{sup 2} distribution of Porter and Thomas. The pdf's take two possible channel spins into account. This code ismore » a tool which evaluators will use to construct resonance parameters and help to assign resonance spin. The use of this tool is expected to reduce time and effort in the evaluation procedure, since the number of repeated runs of the fitting code (e.g., SAMMY) may be reduced.« less

Adaptive Randomization of Veliparib-Carboplatin Treatment in Breast Cancer.

PubMed

Rugo, Hope S; Olopade, Olufunmilayo I; DeMichele, Angela; Yau, Christina; van 't Veer, Laura J; Buxton, Meredith B; Hogarth, Michael; Hylton, Nola M; Paoloni, Melissa; Perlmutter, Jane; Symmans, W Fraser; Yee, Douglas; Chien, A Jo; Wallace, Anne M; Kaplan, Henry G; Boughey, Judy C; Haddad, Tufia C; Albain, Kathy S; Liu, Minetta C; Isaacs, Claudine; Khan, Qamar J; Lang, Julie E; Viscusi, Rebecca K; Pusztai, Lajos; Moulder, Stacy L; Chui, Stephen Y; Kemmer, Kathleen A; Elias, Anthony D; Edmiston, Kirsten K; Euhus, David M; Haley, Barbara B; Nanda, Rita; Northfelt, Donald W; Tripathy, Debasish; Wood, William C; Ewing, Cheryl; Schwab, Richard; Lyandres, Julia; Davis, Sarah E; Hirst, Gillian L; Sanil, Ashish; Berry, Donald A; Esserman, Laura J

2016-07-07

The genetic and clinical heterogeneity of breast cancer makes the identification of effective therapies challenging. We designed I-SPY 2, a phase 2, multicenter, adaptively randomized trial to screen multiple experimental regimens in combination with standard neoadjuvant chemotherapy for breast cancer. The goal is to match experimental regimens with responding cancer subtypes. We report results for veliparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, combined with carboplatin. In this ongoing trial, women are eligible for participation if they have stage II or III breast cancer with a tumor 2.5 cm or larger in diameter; cancers are categorized into eight biomarker subtypes on the basis of status with regard to human epidermal growth factor receptor 2 (HER2), hormone receptors, and a 70-gene assay. Patients undergo adaptive randomization within each biomarker subtype to receive regimens that have better performance than the standard therapy. Regimens are evaluated within 10 biomarker signatures (i.e., prospectively defined combinations of biomarker subtypes). Veliparib-carboplatin plus standard therapy was considered for HER2-negative tumors and was therefore evaluated in 3 signatures. The primary end point is pathological complete response. Tumor volume changes measured by magnetic resonance imaging during treatment are used to predict whether a patient will have a pathological complete response. Regimens move on from phase 2 if and when they have a high Bayesian predictive probability of success in a subsequent phase 3 neoadjuvant trial within the biomarker signature in which they performed well. With regard to triple-negative breast cancer, veliparib-carboplatin had an 88% predicted probability of success in a phase 3 trial. A total of 72 patients were randomly assigned to receive veliparib-carboplatin, and 44 patients were concurrently assigned to receive control therapy; at the completion of chemotherapy, the estimated rates of pathological complete response in the triple-negative population were 51% (95% Bayesian probability interval [PI], 36 to 66%) in the veliparib-carboplatin group versus 26% (95% PI, 9 to 43%) in the control group. The toxicity of veliparib-carboplatin was greater than that of the control. The process used in our trial showed that veliparib-carboplatin added to standard therapy resulted in higher rates of pathological complete response than standard therapy alone specifically in triple-negative breast cancer. (Funded by the QuantumLeap Healthcare Collaborative and others; I-SPY 2 TRIAL ClinicalTrials.gov number, NCT01042379.).

PICKY: a novel SVD-based NMR spectra peak picking method

PubMed Central

Alipanahi, Babak; Gao, Xin; Karakoc, Emre; Donaldson, Logan; Li, Ming

2009-01-01

Motivation: Picking peaks from experimental NMR spectra is a key unsolved problem for automated NMR protein structure determination. Such a process is a prerequisite for resonance assignment, nuclear overhauser enhancement (NOE) distance restraint assignment, and structure calculation tasks. Manual or semi-automatic peak picking, which is currently the prominent way used in NMR labs, is tedious, time consuming and costly. Results: We introduce new ideas, including noise-level estimation, component forming and sub-division, singular value decomposition (SVD)-based peak picking and peak pruning and refinement. PICKY is developed as an automated peak picking method. Different from the previous research on peak picking, we provide a systematic study of the proposed method. PICKY is tested on 32 real 2D and 3D spectra of eight target proteins, and achieves an average of 88% recall and 74% precision. PICKY is efficient. It takes PICKY on average 15.7 s to process an NMR spectrum. More important than these numbers, PICKY actually works in practice. We feed peak lists generated by PICKY to IPASS for resonance assignment, feed IPASS assignment to SPARTA for fragments generation, and feed SPARTA fragments to FALCON for structure calculation. This results in high-resolution structures of several proteins, for example, TM1112, at 1.25 Å. Availability: PICKY is available upon request. The peak lists of PICKY can be easily loaded by SPARKY to enable a better interactive strategy for rapid peak picking. Contact: mli@uwaterloo.ca PMID:19477998

Unenhanced MR Angiography of Uterine and Ovarian Arteries after Uterine Artery Embolization: Differences between Patients with Incomplete and Complete Fibroid Infarction

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

Mori, Kensaku, E-mail: moriken@md.tsukuba.ac.jp; Saida, Tsukasa; Shibuya, Yoko

Purpose: To compare the status of uterine and ovarian arteries after uterine artery embolization (UAE) in patients with incomplete and complete fibroid infarction via unenhanced 3D time-of-flight magnetic resonance (MR) angiography. Materials and Methods: Thirty-five consecutive women (mean age 43 years; range 26-52 years) with symptomatic uterine fibroids underwent UAE and MR imaging before and within 2 months after UAE. The patients were divided into incomplete and complete fibroid infarction groups on the basis of the postprocedural gadolinium-enhanced MR imaging findings. Two independent observers reviewed unenhanced MR angiography before and after UAE to determine bilateral uterine and ovarian arterial flowmore » scores. The total arterial flow scores were calculated by summing the scores of the 4 arteries. All scores were compared with the Mann-Whitney test. Results: Fourteen and 21 patients were assigned to the incomplete and complete fibroid infarction groups, respectively. The total arterial flow score in the incomplete fibroid infarction group was significantly greater than that in the complete fibroid infarction group (P = 0.019 and P = 0.038 for observers 1 and 2, respectively). In 3 patients, additional therapy was recommended for insufficient fibroid infarction. In 1 of the 3 patients, bilateral ovarian arteries were invisible before UAE but seemed enlarged after UAE. Conclusion: The total arterial flow from bilateral uterine and ovarian arteries in patients with incomplete fibroid infarction is less well reduced than in those with complete fibroid infarction. Postprocedural MR angiography provides useful information to estimate the cause of insufficient fibroid infarction in individual cases.« less

The impact of alternative incentive schemes on completion of health risk assessments.

PubMed

Haisley, Emily; Volpp, Kevin G; Pellathy, Thomas; Loewenstein, George

2012-01-01

The biggest challenge for corporate wellness initiatives is low rates of employee participation. We test whether a behavioral economic approach to incentive design (i.e., a lottery) is more effective than a direct economic payment of equivalent monetary value (i.e., a grocery gift certificate) in encouraging employees to complete health risk assessments (HRAs). Employees were assigned to one of three arms. Assignment to a treatment arm versus the nontreatment arm was determined by management. Assignment to an arm among those eligible for treatment was randomized by office. A large health care management and information technology consulting company. A total of 1299 employees across 14 offices participated. All employees were eligible to receive $25 for completing the HRA. Those in the lottery condition were assigned to teams of four to eight people and, conditional on HRA completion, were entered into a lottery with a prize of $100 (expected value, $25) and a bonus value of an additional $25 if 80% of team members participated. Those in the grocery gift certificate condition who completed an HRA received a $25 grocery gift certificate. Those in the comparison condition received no additional incentive. HRA completion rates. Logistic regression analysis. HRA completion rates were significantly higher among participations in the lottery incentive condition (64%) than in both the grocery gift certificate condition (44%) and the comparison condition (40%). Effects were larger for lower-income employees, as indicated by a significant interaction between income and the lottery incentive. Lottery incentives that incorporate regret aversion and social pressure can provide higher impact for the same amount of money as simple economic incentives.

Bound and resonance states of the dipolar anion of hydrogen cyanide: Competition between threshold effects and rotation in an open quantum system

DOE PAGES

Fossez, K.; Michel, N.; Nazarewicz, W.; ...

2015-01-12

In this paper, bound and resonance states of the dipole-bound anion of hydrogen cyanide HCN – are studied using a nonadiabatic pseudopotential method and the Berggren expansion technique involving bound states, decaying resonant states, and nonresonant scattering continuum. We devise an algorithm to identify the resonant states in the complex energy plane. To characterize spatial distributions of electronic wave functions, we introduce the body-fixed density and use it to assign families of resonant states into collective rotational bands. We find that the nonadiabatic coupling of electronic motion to molecular rotation results in a transition from the strong-coupling to weak-coupling regime.more » In the strong-coupling limit, the electron moving in a subthreshold, spatially extended halo state follows the rotational motion of the molecule. Above the ionization threshold, the electron's motion in a resonance state becomes largely decoupled from molecular rotation. Finally, the widths of resonance-band members depend primarily on the electron orbital angular momentum.« less

A Comparison of Electronic and Paper-Based Assignment Submission and Feedback

ERIC Educational Resources Information Center

Bridge, Pete; Appleyard, Rob

2008-01-01

This paper presents the results of a study evaluating student perceptions of online assignment submission. 47 students submitted assignments and received feedback via features within the Virtual Learning Environment Blackboard[TM]. The students then completed questionnaires comparing their experience of online submission and feedback with…

Statistical Literacy Social Media Project for the Masses

ERIC Educational Resources Information Center

Gundlach, Ellen; Maybee, Clarence; O'Shea, Kevin

2015-01-01

This article examines a social media assignment used to teach and practice statistical literacy with over 400 students each semester in large-lecture traditional, fully online, and flipped sections of an introductory-level statistics course. Following the social media assignment, students completed a survey on how they approached the assignment.…

Automating Formative and Summative Feedback for Individualised Assignments

ERIC Educational Resources Information Center

Hamilton, Ian Robert

2009-01-01

Purpose: The purpose of this paper is to report on the rationale behind the use of a unique paper-based individualised accounting assignment, which automated the provision to students of immediate formative and timely summative feedback. Design/methodology/approach: As students worked towards completing their assignment, the package provided…

Learner Perspectives Regarding Device Type in Technology-Assisted Language Learning

ERIC Educational Resources Information Center

Ko, Myong-Hee

2017-01-01

This study compared learner perspectives regarding using PCs and smartphones as learning devices. A total of 167 Korean university students completed online assignments designed to maximize interaction with these devices. The assignments required students to submit their responses regarding assigned reading passages for a semester. Then they…

Influence of Student Engagement, Moods and Completed Assignments with on Normalized Gains and Growth in Reading Literature Using iPads

ERIC Educational Resources Information Center

Hepworth, A. J.

2014-01-01

The purpose of this study was to investigate how engagement, mood and number of assignments completed on computerized differentiated homework using an iPad in a one-to-one mobile device environment influenced the growth index and normalized gain in reading literature benchmark assessments of students in grades five, six, and seven. Furthermore,…

The Monte Carlo Quiz: Encouraging Punctual Completion and Deep Processing of Assigned Readings

ERIC Educational Resources Information Center

Fernald, Peter S.

2004-01-01

The Monte Carlo Quiz (MCQ), a single-item quiz, is so named because chance, with the roll of a die, determines (a) whether the quiz is administered; (b) the specific article, chapter, or section of the assigned reading that the quiz covers; and (c) the particular question that makes up the quiz. The MCQ encourages both punctual completion and deep…

The 18Ne(α,p)21Na breakout reaction in x-ray bursts: Experimental determination of spin-parities for α resonances in 22Mg via resonant elastic scattering of 21Na+p

NASA Astrophysics Data System (ADS)

He, J. J.; Zhang, L. Y.; Parikh, A.; Xu, S. W.; Yamaguchi, H.; Kahl, D.; Kubono, S.; Hu, J.; Ma, P.; Chen, S. Z.; Wakabayashi, Y.; Sun, B. H.; Wang, H. W.; Tian, W. D.; Chen, R. F.; Guo, B.; Hashimoto, T.; Togano, Y.; Hayakawa, S.; Teranishi, T.; Iwasa, N.; Yamada, T.; Komatsubara, T.

2013-07-01

The 18Ne(α,p)21Na reaction provides a pathway for breakout from the hot CNO cycles to the rp process in type-I x-ray bursts. To better determine this astrophysical reaction rate, the resonance parameters of the compound nucleus 22Mg have been investigated by measuring the resonant elastic scattering of 21Na+p. An 89 MeV 21Na radioactive ion beam was produced at the CNS Radioactive Ion Beam Separator and bombarded an 8.8 mg/cm2 thick polyethylene target. The recoiled protons were measured at scattering angles of θc.m.≈175∘ and 152∘ by three ΔE-E silicon telescopes. The excitation function was obtained with a thick-target method over energies Ex(22Mg) = 5.5-9.2 MeV. The resonance parameters have been determined through an R-matrix analysis. For the first time, the Jπ values for ten states above the α threshold in 22Mg have been experimentally determined in a single consistent measurement. We have made three new Jπ assignments and confirmed seven of the ten tentative assignments in the previous work. The 18Ne(α,p)21Na reaction rate has been recalculated, and the astrophysical impact of our new rate has been investigated through one-zone postprocessing x-ray burst calculations. We find that the 18Ne(α,p)21Na rate significantly affects the peak nuclear energy generation rate and the onset temperature of this breakout reaction in these phenomena.

The Tandem of Full Spin Analysis and qHNMR for the Quality Control of Botanicals Exemplified with Ginkgo biloba

PubMed Central

Napolitano, José G.; Gödecke, Tanja; Rodríguez-Brasco, María F.; Jaki, Birgit U.; Chen, Shao-Nong; Lankin, David C.; Pauli, GuidoF.

2012-01-01

Botanical dietary supplements and herbal remedies are widely used for health promotion and disease prevention. Due to the high chemical complexity of these natural products, it is essential to develop new analytical strategies to guarantee their quality and consistency. In particular, the precise characterization of multiple botanical markers remains a challenge. This study demonstrates how a combination of computer-aided spectral analysis and 1D quantitative 1H NMR spectroscopy (qHNMR) generates the analytical foundation for innovative means of simultaneously identifying and quantifying botanical markers in complex mixtures. First, comprehensive 1H NMR profiles (fingerprints) of selected botanical markers were generated via 1H iterative Full Spin Analysis (HiFSA) with PERCH. Next, the 1H fingerprints were used to assign specific 1H resonances in the NMR spectra of reference materials, enriched fractions and crude extracts of Ginkgo biloba leaves. These 1H fingerprints were then used to verify the assignments by 2D NMR. Subsequently, a complete purity and composition assessment by means of 1D qHNMR was conducted. As its major strengths, this tandem approach enables the simultaneous quantification of multiple constituents without the need for identical reference materials, the semi-quantitative determination of particular sub-classes of components, and the detection of impurities and adulterants. PMID:22332915

Red-excitation resonance Raman analysis of the nu(Fe=O) mode of ferryl-oxo hemoproteins.

PubMed

Ikemura, Kenichiro; Mukai, Masahiro; Shimada, Hideo; Tsukihara, Tomitake; Yamaguchi, Satoru; Shinzawa-Itoh, Kyoko; Yoshikawa, Shinya; Ogura, Takashi

2008-11-05

The Raman excitation profile of the nuFe O mode of horseradish peroxidase compound II exhibits a maximum at 580 nm. This maximum is located within an absorption band with a shoulder assignable to an oxygen-to-iron charge transfer band on the longer wavelength side of the alpha-band. Resonance Raman bands of the nuFe O mode of various ferryl-oxo type hemoproteins measured at 590 nm excitation indicate that many hemoproteins in the ferryl-oxo state have an oxygen-to-iron charge transfer band in the visible region. Since this red-excited resonance Raman technique causes much less photochemical damage in the proteins relative to blue-excited resonance Raman spectroscopy, it produces a higher signal-to-noise ratio and thus represents a powerful tool for investigations of ferryl-oxo intermediates of hemoproteins.

Correlation of probability scores of placenta accreta on magnetic resonance imaging with hemorrhagic morbidity.

PubMed

Lim, Grace; Horowitz, Jeanne M; Berggruen, Senta; Ernst, Linda M; Linn, Rebecca L; Hewlett, Bradley; Kim, Jennifer; Chalifoux, Laurie A; McCarthy, Robert J

2016-11-01

To evaluate the hypothesis that assigning grades to magnetic resonance imaging (MRI) findings of suspected placenta accreta will correlate with hemorrhagic outcomes. We chose a single-center, retrospective, observational design. Nulliparous or multiparous women who had antenatal placental MRI performed at a tertiary level academic hospital were included. Cases with antenatal placental MRI were included and compared with cases without MRI performed. Two radiologists assigned a probability score for accreta to each study. Estimated blood loss and transfusion requirements were compared among groups by the Kruskal-Wallis H test. Thirty-five cases had placental MRI performed. MRI performance was associated with higher blood loss compared with the non-MRI group (2600 [1400-4500]mL vs 900[600-1500]mL, P<.001). There was no difference in estimated blood loss (P=.31) or transfusion (P=.57) among the MRI probability groups. In cases of suspected placenta accreta, probability scores for antenatal placental MRI may not be associated with increasing degrees of hemorrhage. Continued research is warranted to determine the effectiveness of assigning probability scores for antenatal accreta imaging studies, combined with clinical indices of suspicion, in assisting with antenatal multidisciplinary team planning for operative management of this morbid condition. Copyright © 2016 Elsevier Inc. All rights reserved.

The effect of role assignment in high fidelity patient simulation on nursing students: An experimental research study.

PubMed

Weiler, Dustin T; Gibson, Andrea L; Saleem, Jason J

2018-04-01

Previous studies have evaluated the effectiveness of high fidelity patient simulators (HFPS) on nursing training; however, a gap exists on the effects of role assignment on critical thinking, self-efficacy, and situation awareness skills in team-based simulation scenarios. This study aims to determine if role assignment and the involvement level related to the roles yields significant effects and differences in critical thinking, situation awareness and self-efficacy scores in team-based high-fidelity simulation scenarios. A single factorial design with five levels and random assignment was utilized. A public university-sponsored simulation center in the United States of America. A convenience sample of 69 junior-level baccalaureate nursing students was recruited for participation. Participants were randomly assigned one of five possible roles and completed pre-simulation critical thinking and self-efficacy assessments prior to the simulation beginning. Playing within their assigned roles, participants experienced post-partum hemorrhaging scenario using an HFPS. After completing the simulation, participants completed a situation awareness assessment and a post-simulation critical thinking and self-efficacy assessment. Role assignment was found to have a statistically significant effect on critical thinking skills and a statistically significant difference in various areas of self-efficacy was also noted. However, no statistical significance in situation awareness abilities was found. Results support the notion that certain roles required the participant to be more involved with the simulation scenario, which may have yielded higher critical thinking and self-efficacy scores than roles that required a lesser level of involvement. Copyright © 2018 Elsevier Ltd. All rights reserved.

Response of MDOF strongly nonlinear systems to fractional Gaussian noises.

PubMed

Deng, Mao-Lin; Zhu, Wei-Qiu

2016-08-01

In the present paper, multi-degree-of-freedom strongly nonlinear systems are modeled as quasi-Hamiltonian systems and the stochastic averaging method for quasi-Hamiltonian systems (including quasi-non-integrable, completely integrable and non-resonant, completely integrable and resonant, partially integrable and non-resonant, and partially integrable and resonant Hamiltonian systems) driven by fractional Gaussian noise is introduced. The averaged fractional stochastic differential equations (SDEs) are derived. The simulation results for some examples show that the averaged SDEs can be used to predict the response of the original systems and the simulation time for the averaged SDEs is less than that for the original systems.

The guided-mode resonance biosensor: principles, technology, and implementation

NASA Astrophysics Data System (ADS)

Magnusson, Robert; Lee, Kyu J.; Hemmati, Hafez; Ko, Yeong Hwan; Wenner, Brett R.; Allen, Jeffery W.; Allen, Monica S.; Gimlin, Susanne; Weidanz, Debra Wawro

2018-02-01

The guided-mode resonance (GMR) sensor operates with quasi-guided modes induced in periodic films. The resonance is enabled by 1D or 2D nanopatterns that are expeditiously fabricated. Optical sensors are needed in many fields including medical diagnostics, chemical analyses, and environmental monitoring. Inducing resonance in multiple modes enables extraction of complete bioreaction information including the biolayer thickness, biolayer refractive index, and any change in the refractive index in the background buffer solution. Thus, we refer to this version of the GMR sensor as the complete biosensor. We address the fundamentals, state of technological development, and implementation of this basic sensor modality.

Response of MDOF strongly nonlinear systems to fractional Gaussian noises

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

Deng, Mao-Lin; Zhu, Wei-Qiu, E-mail: wqzhu@zju.edu.cn

2016-08-15

In the present paper, multi-degree-of-freedom strongly nonlinear systems are modeled as quasi-Hamiltonian systems and the stochastic averaging method for quasi-Hamiltonian systems (including quasi-non-integrable, completely integrable and non-resonant, completely integrable and resonant, partially integrable and non-resonant, and partially integrable and resonant Hamiltonian systems) driven by fractional Gaussian noise is introduced. The averaged fractional stochastic differential equations (SDEs) are derived. The simulation results for some examples show that the averaged SDEs can be used to predict the response of the original systems and the simulation time for the averaged SDEs is less than that for the original systems.

Use of a Mobile Device Simulation as a Preclass Active Learning Exercise.

PubMed

Keegan, Robert D; Oliver, M Cecile; Stanfill, Teresa J; Stevens, Kevin V; Brown, Gary R; Ebinger, Michael; Gay, John M

2016-01-01

Research shows that preclass activities introducing new material can increase student performance. In an effort to engage students in an active learning, preclass activity, the authors developed a mobile application. Eighty-four nursing students were assigned a preclass reading exercise, whereas 32 students completed the preclass simulation scenario on their mobile device. All students completed the same electronic fetal monitoring (EFM) quiz 1 week following the lecture. The effects of reading or simulation on student quiz performance was evaluated with a student's paired t test, using an alpha of .05. Students completing the preclass simulation scored higher on the EFM quiz, compared with students assigned the preclass reading (85% versus 70% correct answers, p = .01). Student survey data indicated that the mobile device simulation was perceived as an engaging and desirable instructional tool. Nursing students completing the mobile device EFM preclass simulation outperformed the students who were given the traditional reading assignment. Copyright 2016, SLACK Incorporated.

Evaluation of a Brief Homework Assignment Designed to Reduce Citation Problems

ERIC Educational Resources Information Center

Schuetze, Pamela

2004-01-01

I evaluated a brief homework assignment designed to reduce citation problems in research-based term papers. Students in 2 developmental psychology classes received a brief presentation and handout defining plagiarism with tips on how to cite sources to avoid plagiarizing. In addition, students in 1 class completed 2 brief homework assignments in…

Assignment Choice: Do Students Choose Briefer Assignments or Finishing What They Started?

ERIC Educational Resources Information Center

Hawthorn-Embree, Meredith L.; Skinner, Christopher H.; Parkhurst, John; O'Neil, Michael; Conley, Elisha

2010-01-01

Academic skill development requires engagement in effortful academic behaviors. Although students may be more likely to choose to engage in behaviors that require less effort, they also may be motivated to complete assignments that they have already begun. Seventh-grade students (N = 88) began a mathematics computation worksheet, but were stopped…

Raman spectroscopy as a tool in differentiating conjugated polyenes from synthetic and natural sources.

PubMed

Fernandes, Rafaella F; Maia, Lenize F; Couri, Mara R C; Costa, Luiz Antonio S; de Oliveira, Luiz Fernando C

2015-01-05

This work presents the Raman spectroscopic characterization of synthetic analogs of natural conjugated polyenals found in octocorals, focusing the unequivocal identification of the chemical species present in these systems. The synthetic material was produced by the autocondensation reaction of crotonaldehyde, generating a demethylated conjugated polyene containing 11 carbon-carbon double bonds, with just a methyl group on the end of the carbon chain. The resonance Raman spectra of such pigment has shown the existence of enhanced modes assigned to ν₁(CC) and ν₂(CC) modes of the main chain. For the resonance Raman spectra of natural pigments from octocorals collected in the Brazilian coast, besides the previously cited bands, it could be also observed the presence of the ν₄(CCH₃), related to the vibrational mode who describes the vibration of the methyl group of the central carbon chain of carotenoids. Other interesting point is the observation of overtones and combination bands, which for carotenoids involves the presence of the ν₄ mode, whereas for the synthetic polyene this band, besides be seen at a slightly different wavenumber position, does not appear as an enhanced mode and also as a combination, such as for the natural carotenoids. Theoretical molecular orbital analysis of polyenal-11 and lycopene has shown the structural differences which are also responsible for the resonance Raman data, based on the appearance of the (CH3) vibrational mode in the resonant transition only for lycopene. At last, the Raman band at ca. 1010 cm(-1), assigned to the (CH₃) vibrational mode, can be used for attributing the presence of each one of the conjugated polyenes: the resonance Raman spectrum containing the band at ca. 1010 cm(-1) refers to the carotenoid (in this case lycopene), and the absence of such band in resonance conditions refers to the polyenal (in this case the polyenal-11). Copyright © 2014 Elsevier B.V. All rights reserved.

Raman spectroscopy as a tool in differentiating conjugated polyenes from synthetic and natural sources

NASA Astrophysics Data System (ADS)

Fernandes, Rafaella F.; Maia, Lenize F.; Couri, Mara R. C.; Costa, Luiz Antonio S.; de Oliveira, Luiz Fernando C.

2015-01-01

This work presents the Raman spectroscopic characterization of synthetic analogs of natural conjugated polyenals found in octocorals, focusing the unequivocal identification of the chemical species present in these systems. The synthetic material was produced by the autocondensation reaction of crotonaldehyde, generating a demethylated conjugated polyene containing 11 carbon-carbon double bonds, with just a methyl group on the end of the carbon chain. The resonance Raman spectra of such pigment has shown the existence of enhanced modes assigned to ν1(Cdbnd C) and ν2(Csbnd C) modes of the main chain. For the resonance Raman spectra of natural pigments from octocorals collected in the Brazilian coast, besides the previously cited bands, it could be also observed the presence of the ν4(Csbnd CH3), related to the vibrational mode who describes the vibration of the methyl group of the central carbon chain of carotenoids. Other interesting point is the observation of overtones and combination bands, which for carotenoids involves the presence of the ν4 mode, whereas for the synthetic polyene this band, besides be seen at a slightly different wavenumber position, does not appear as an enhanced mode and also as a combination, such as for the natural carotenoids. Theoretical molecular orbital analysis of polyenal-11 and lycopene has shown the structural differences which are also responsible for the resonance Raman data, based on the appearance of the (sbnd CH3) vibrational mode in the resonant transition only for lycopene. At last, the Raman band at ca. 1010 cm-1, assigned to the (sbnd CH3) vibrational mode, can be used for attributing the presence of each one of the conjugated polyenes: the resonance Raman spectrum containing the band at ca. 1010 cm-1 refers to the carotenoid (in this case lycopene), and the absence of such band in resonance conditions refers to the polyenal (in this case the polyenal-11).

Sequence-specific backbone resonance assignments and microsecond timescale molecular dynamics simulation of human eosinophil-derived neurotoxin.

PubMed

Gagné, Donald; Narayanan, Chitra; Bafna, Khushboo; Charest, Laurie-Anne; Agarwal, Pratul K; Doucet, Nicolas

2017-10-01

Eight active canonical members of the pancreatic-like ribonuclease A (RNase A) superfamily have been identified in human. All structural homologs share similar RNA-degrading functions, while also cumulating other various biological activities in different tissues. The functional homologs eosinophil-derived neurotoxin (EDN, or RNase 2) and eosinophil cationic protein (ECP, or RNase 3) are known to be expressed and secreted by eosinophils in response to infection, and have thus been postulated to play an important role in host defense and inflammatory response. We recently initiated the biophysical and dynamical investigation of several vertebrate RNase homologs and observed that clustering residue dynamics appear to be linked with the phylogeny and biological specificity of several members. Here we report the 1 H, 13 C and 15 N backbone resonance assignments of human EDN (RNase 2) and its molecular dynamics simulation on the microsecond timescale, providing means to pursue this comparative atomic-scale functional and dynamical analysis by NMR and computation over multiple time frames.

Methods Development for Spectral Simplification of Room-Temperature Rotational Spectra

NASA Astrophysics Data System (ADS)

Kent, Erin B.; Shipman, Steven

2014-06-01

Room-temperature rotational spectra are dense and difficult to assign, and so we have been working to develop methods to accelerate this process. We have tested two different methods with our waveguide-based spectrometer, which operates from 8.7 to 26.5 GHz. The first method, based on previous work by Medvedev and De Lucia, was used to estimate lower state energies of transitions by performing relative intensity measurements at a range of temperatures between -20 and +50 °C. The second method employed hundreds of microwave-microwave double resonance measurements to determine level connectivity between rotational transitions. The relative intensity measurements were not particularly successful in this frequency range (the reasons for this will be discussed), but the information gleaned from the double-resonance measurements can be incorporated into other spectral search algorithms (such as autofit or genetic algorithm approaches) via scoring or penalty functions to help with the spectral assignment process. I.R. Medvedev, F.C. De Lucia, Astrophys. J. 656, 621-628 (2007).

EPR, optical and superposition model study of Mn2+ doped L+ glutamic acid

NASA Astrophysics Data System (ADS)

Kripal, Ram; Singh, Manju

2015-12-01

Electron paramagnetic resonance (EPR) study of Mn2+ doped L+ glutamic acid single crystal is done at room temperature. Four interstitial sites are observed and the spin Hamiltonian parameters are calculated with the help of large number of resonant lines for various angular positions of external magnetic field. The optical absorption study is also done at room temperature. The energy values for different orbital levels are calculated, and observed bands are assigned as transitions from 6A1g(s) ground state to various excited states. With the help of these assigned bands, Racah inter-electronic repulsion parameters B = 869 cm-1, C = 2080 cm-1 and cubic crystal field splitting parameter Dq = 730 cm-1 are calculated. Zero field splitting (ZFS) parameters D and E are calculated by the perturbation formulae and crystal field parameters obtained using superposition model. The calculated values of ZFS parameters are in good agreement with the experimental values obtained by EPR.

Collaborative group work: effects of group size and assignment structure on learning gain, student satisfaction and perceived participation.

PubMed

Kooloos, Jan G M; Klaassen, Tim; Vereijken, Mayke; Van Kuppeveld, Sascha; Bolhuis, Sanneke; Vorstenbosch, Marc

2011-01-01

Collaborative group sessions in Nijmegen include 15 students who work all together on a group assignment. Sometimes, the group is split-up in three and every subgroup elaborates a part of the assignment. At the end, they peer-teach each other. It is believed that the split-up enhances participation and therefore learning gain. To establish the effect of group size and structure of the assignment on the perceived participation, the satisfaction and learning gain of collaborative group sessions. In this study, 27 groups of 15 students were equally divided into: A-group: all 15 students working on the complete assignment. B-group: subgroups of 5 students working on the complete assignment. C-group: subgroups of 5 students working on a smaller part, and peer-teaching each other at the end of the group session. All students took a pre-test, a post-test and a follow-up test and completed a questionnaire. Questionnaires were analyzed with a one-way analysis of variance (ANOVA) and post hoc by multiple comparisons. Learning gain was analyzed using a repeated measures ANOVA. A group size effect is observed in favor of working in subgroups. Perceived participation of the students differs between A and B (p ≤ 0.001) and between A and C (p ≤ 0.001), but not between B and C. Also, an assignment effect is found in favor of the smaller assignment combined with peer-teaching. The students' satisfaction differs between A and C (p ≤ 0.003) and between B and C (p ≤ 0.001), but not between A and B. The C-group also shows higher test results (p ≤ 0.043). The students prefer smaller groups as well as smaller assignments including peer-teaching. A possible larger learning gain of this format needs to be re-investigated.

Impact of Patient Empathy Modeling on Pharmacy Students Caring for the Underserved

PubMed Central

Chen, Judy T.; LaLopa, Joseph

2008-01-01

Objective To determine the impact of the Patient Empathy Modeling pedagogy on students' empathy towards caring for the underserved during an advanced pharmacy practice experience (APPE). Design Pharmacy students completing an APPE at 2 primary care clinics participated in a Patient Empathy Modeling assignment for 10 days. Each student “became the patient,” simulating the life of an actual patient with multiple chronic diseases who was coping with an economic, cultural, or communication barrier to optimal healthcare. Students completed the Jefferson Scale of Physician Empathy (JSPE) before and after completing the assignment, and wrote daily journal entries and a reflection paper. Assessment Twenty-six students completed the PEM exercises from 2005-2006. Scores on the JSPE improved. Students' comments in journals and reflection papers revealed 3 major themes: greater appreciation of the difficulty patients have with adherence to medication and treatment regimens, increased empathy for patients from different backgrounds and patients with medical and psychosocial challenges, and improved ability to apply the lessons learned in the course to their patient care roles. Conclusion A Patient Empathy Modeling assignment improved pharmacy students' empathy toward underserved populations. Integrating the assignment within an APPE allowed students to immediately begin applying the knowledge and insight gained from the exercise. PMID:18483606

Combined nuclear magnetic resonance spectroscopy and molecular dynamics study of growth hormone releasing hexapeptide GHRP-6 and a cyclic analogue.

PubMed

Fernández-Oliva, Miguel; Santana, Héctor; Suardíaz, Reynier; Gavín, José A; Pérez, Carlos S

2012-05-01

The Growth Hormone Releasing Hexapeptide, GHRP-6 was the first of a family of synthetic peptides that enhance the release of the Growth Hormone by the pituitary gland in a dose-dependent manner. Since its discovery, it has been used as a benchmark and starting point in numerous researches aiming to obtain new drugs. Complete resonance assignment of GHRP-6 NMR spectra in both open and cyclic forms are reported, showing some differences to random coil chemical shifts. Connectivities observed in the ROESY spectra indicate spatial proximity between the aromatic residues side-chains in both molecules, as well as between residues DPhe5 and Lys6 sidechains. An ensemble of 10 structures was generated for each one of the molecules, showing RMSD values indicative of nonrandom structures. Molecular Dynamics simulations, both with and without explicit solvent, were carried out for GHRP-6 and its cyclic analogue. Conformational analysis performed on the trajectories showed a nonrandom structure with a well preserved backbone. The presence of geometrical patterns resembling those typical of π-π interactions in both peptides, suggest that this kind of interactions may be relevant for the biological activity of GHRP-6. Same conclusion can be drawn from the spatial proximity of residues DPhe5 and Lys6 sidechains. Copyright © 2012 John Wiley & Sons, Ltd.

Improving Analytical Characterization of Glycoconjugate Vaccines through Combined High-Resolution MS and NMR: Application to Neisseria meningitidis Serogroup B Oligosaccharide-Peptide Glycoconjugates.

PubMed

Yu, Huifeng; An, Yanming; Battistel, Marcos D; Cipollo, John F; Freedberg, Darón I

2018-04-17

Conjugate vaccines are highly heterogeneous in terms of glycosylation sites and linked oligosaccharide length. Therefore, the characterization of conjugate vaccines' glycosylation state is challenging. However, improved product characterization can lead to enhancements in product control and product quality. Here, we present a synergistic combination of high-resolution mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR) for the analysis of glycoconjugates. We use the power of this strategy to characterize model polysaccharide conjugates and to demonstrate a detailed level of glycoproteomic analysis. These are first steps on model compounds that will help untangle the details of complex product characterization in conjugate vaccines. Ultimately, this strategy can be applied to enhance the characterization of polysaccharide conjugate vaccines. In this study, we lay the groundwork for the analysis of conjugate vaccines. To begin this effort, oligosaccharide-peptide conjugates were synthesized by periodate oxidation of an oligosaccharide of a defined length, α,2-8 sialic acid trimer, followed by a reductive amination, and linking the trimer to an immunogenic peptide from tetanus toxoid. Combined mass spectrometry and nuclear magnetic resonance were used to monitor each reaction and conjugation products. Complete NMR peak assignment and detailed MS information on oxidized oligosialic acid and conjugates are reported. These studies provide a deeper understanding of the conjugation chemistry process and products, which can lead to a better controlled production process.

Nanoimaging of resonating hyperbolic polaritons in linear boron nitride antennas

PubMed Central

Alfaro-Mozaz, F. J.; Alonso-González, P.; Vélez, S.; Dolado, I.; Autore, M.; Mastel, S.; Casanova, F.; Hueso, L. E.; Li, P.; Nikitin, A. Y.; Hillenbrand, R.

2017-01-01

Polaritons in layered materials—including van der Waals materials—exhibit hyperbolic dispersion and strong field confinement, which makes them highly attractive for applications including optical nanofocusing, sensing and control of spontaneous emission. Here we report a near-field study of polaritonic Fabry–Perot resonances in linear antennas made of a hyperbolic material. Specifically, we study hyperbolic phonon–polaritons in rectangular waveguide antennas made of hexagonal boron nitride (h-BN, a prototypical van der Waals crystal). Infrared nanospectroscopy and nanoimaging experiments reveal sharp resonances with large quality factors around 100, exhibiting atypical modal near-field patterns that have no analogue in conventional linear antennas. By performing a detailed mode analysis, we can assign the antenna resonances to a single waveguide mode originating from the hybridization of hyperbolic surface phonon–polaritons (Dyakonov polaritons) that propagate along the edges of the h-BN waveguide. Our work establishes the basis for the understanding and design of linear waveguides, resonators, sensors and metasurface elements based on hyperbolic materials and metamaterials. PMID:28589941

ESR investigations on γ-ray irradiated 3-methyl nylon 3

NASA Astrophysics Data System (ADS)

Catiker, Efkan; Guven, Olgun; Ozarslan, Ozdemir; Chipara, Mircea

2008-06-01

Electron spin resonance spectroscopy investigations on γ irradiated 3-methyl nylon 3 (poly-3-methyl β-alanine) are reported. The resonance spectra (recorded after the irradiation in nitrogen atmosphere has been stopped) have been attributed to the parallel and perpendicular components of a triplet line assigned to the delocalization of the uncoupled electron over an effective nuclear spin 1. It was suggested that this effective spin arises from the fast tunneling/rotation of a proton between two positions. The resonance spectra have been simulated with accuracy by using a simplified spin Hamiltonian and assuming Lorentzian-like resonance line shapes and axial asymmetry of the resonance line due to the trapping of free radicals in randomly oriented crystallites. The time evolution of free radicals in nitrogen atmosphere at room temperature has been analyzed. The decay kinetics of stable free radicals in 3-methyl nylon 3 (under inert atmosphere) has been investigated. It was shown that the radiation-induced radicals in inert atmosphere decay through a unimolecular reaction.

Solution structure of the DNA-binding domain of the heat shock transcription factor determined by multidimensional heteronuclear magnetic resonance spectroscopy.

PubMed Central

Damberger, F. F.; Pelton, J. G.; Harrison, C. J.; Nelson, H. C.; Wemmer, D. E.

1994-01-01

The solution structure of the 92-residue DNA-binding domain of the heat shock transcription factor from Kluyveromyces lactis has been determined using multidimensional NMR methods. Three-dimensional (3D) triple resonance, 1H-13C-13C-1H total correlation spectroscopy, and 15N-separated total correlation spectroscopy-heteronuclear multiple quantum correlation experiments were used along with various 2D spectra to make nearly complete assignments for the backbone and side-chain 1H, 15N, and 13C resonances. Five-hundred eighty-three NOE constraints identified in 3D 13C- and 15N-separated NOE spectroscopy (NOESY)-heteronuclear multiple quantum correlation spectra and a 4-dimensional 13C/13C-edited NOESY spectrum, along with 35 phi, 9 chi 1, and 30 hydrogen bond constraints, were used to calculate 30 structures by hybrid distance geometry/stimulated annealing protocol, of which 24 were used for structural comparison. The calculations revealed that a 3-helix bundle packs against a small 4-stranded antiparallel beta-sheet. The backbone RMS deviation (RMSD) for the family of structures was 1.03 +/- 0.19 A with respect to the average structure. The topology is analogous to that of the C-terminal domain of the catabolite gene activator protein and appears to be in the helix-turn-helix family of DNA-binding proteins. The overall fold determined by the NMR data is consistent with recent crystallographic work on this domain (Harrison CJ, Bohm AA, Nelson HCM, 1994, Science 263:224) as evidenced by RMSD between backbone atoms in the NMR and X-ray structures of 1.77 +/- 0.20 A. Several differences were identified some of which may be due to protein-protein interactions in the crystal. PMID:7849597

Calculation and measurement of radiation corrections for plasmon resonances in nanoparticles

NASA Astrophysics Data System (ADS)

Hung, L.; Lee, S. Y.; McGovern, O.; Rabin, O.; Mayergoyz, I.

2013-08-01

The problem of plasmon resonances in metallic nanoparticles can be formulated as an eigenvalue problem under the condition that the wavelengths of the incident radiation are much larger than the particle dimensions. As the nanoparticle size increases, the quasistatic condition is no longer valid. For this reason, the accuracy of the electrostatic approximation may be compromised and appropriate radiation corrections for the calculation of resonance permittivities and resonance wavelengths are needed. In this paper, we present the radiation corrections in the framework of the eigenvalue method for plasmon mode analysis and demonstrate that the computational results accurately match analytical solutions (for nanospheres) and experimental data (for nanorings and nanocubes). We also demonstrate that the optical spectra of silver nanocube suspensions can be fully assigned to dipole-type resonance modes when radiation corrections are introduced. Finally, our method is used to predict the resonance wavelengths for face-to-face silver nanocube dimers on glass substrates. These results may be useful for the indirect measurements of the gaps in the dimers from extinction cross-section observations.

Combining Fourier phase encoding and broadband inversion toward J-edited spectra

NASA Astrophysics Data System (ADS)

Lin, Yulan; Guan, Quanshuai; Su, Jianwei; Chen, Zhong

2018-06-01

Nuclear magnetic resonance (NMR) spectra are often utilized for gathering accurate information relevant to molecular structures and composition assignments. In this study, we develop a homonuclear encoding approach based on imparting a discrete phase modulation of the targeted cross peaks, and combine it with a pure shift experiments (PSYCHE) based J-modulated scheme, providing simple 2D J-edited spectra for accurate measurement of scalar coupling networks. Chemical shifts and J coupling constants of protons coupled to the specific protons are demonstrated along the F2 and F1 dimensions, respectively. Polychromatic pulses by Fourier phase encoding were performed to simultaneously detect several coupling networks. Proton-proton scalar couplings are chosen by a polychromatic pulse and a PSYCHE element. Axis peaks and unwanted couplings are complete eradicated by incorporating a selective COSY block as a preparation period. The theoretical principles and the signal processing procedure are laid out, and experimental observations are rationalized on the basis of theoretical analyses.

'Pharyngocise': Randomized Controlled Trial of Preventative Exercises to Maintain Muscle Structure and Swallowing Function During Head-and-Neck Chemoradiotherapy

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

Carnaby-Mann, Giselle, E-mail: gmann@phhp.ufl.edu; Crary, Michael A.; Schmalfuss, Ilona

2012-05-01

Purpose: Dysphagia after chemoradiotherapy is common. The present randomized clinical trial studied the effectiveness of preventative behavioral intervention for dysphagia compared with the 'usual care.' Methods and Materials: A total of 58 head-and-neck cancer patients treated with chemoradiotherapy were randomly assigned to usual care, sham swallowing intervention, or active swallowing exercises (pharyngocise). The intervention arms were treated daily during chemoradiotherapy. The primary outcome measure was muscle size and composition (determined by T{sub 2}-weighted magnetic resonance imaging). The secondary outcomes included functional swallowing ability, dietary intake, chemosensory function, salivation, nutritional status, and the occurrence of dysphagia-related complications. Results: The swallowing musculaturemore » (genioglossus, hyoglossuss, and mylohyoid) demonstrated less structural deterioration in the active treatment arm. The functional swallowing, mouth opening, chemosensory acuity, and salivation rate deteriorated less in the pharyngocise group. Conclusion: Patients completing a program of swallowing exercises during cancer treatment demonstrated superior muscle maintenance and functional swallowing ability.« less

Ultra-broadband THz time-domain spectroscopy of common polymers using THz air photonics.

PubMed

D'Angelo, Francesco; Mics, Zoltán; Bonn, Mischa; Turchinovich, Dmitry

2014-05-19

Terahertz-range dielectric properties of the common polymers low-density polyethylene (LDPE), cyclic olefin/ethylene copolymer (TOPAS®), polyamide-6 (PA6), and polytetrafluoroethylene (PTFE or Teflon®) are characterized in the ultra-broadband frequency window 2-15 THz, using a THz time-domain spectrometer employing air-photonics for the generation and detection of single-cycle sub-50 fs THz transients. The time domain measurements provide direct access to both the absorption and refractive index spectra. The polymers LDPE and TOPAS® demonstrate negligible absorption and spectrally-flat refractive index across the entire spectroscopy window, revealing the high potential of these polymers for applications in THz photonics such as ultra-broadband polymer-based dielectric mirrors, waveguides, and fibers. Resonant high-frequency polar vibrational modes are observed and assigned in polymers PA6 and PTFE, and their dielectric functions in the complete frequency window 2-15 THz are theoretically reproduced. Our results demonstrate the potential of ultra-broadband air-photonics-based THz time domain spectroscopy as a valuable analytic tool for materials science.

Synthesis, crystal growth, characterization and theoretical studies of 4-aminobenzophenonium picrate

NASA Astrophysics Data System (ADS)

Aditya Prasad, A.; Muthu, K.; Rajasekar, M.; Meenatchi, V.; Meenakshisundaram, S. P.

2015-01-01

Single crystals of 4-aminobenzophenonium picrate (4ABPP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1,v/v) containing equimolar quantities of picric acid and 4-aminobenzophenone. The proton and carbon signals are confirmed by nuclear magnetic resonance spectroscopy. The various functional groups present in the molecule are identified by FT-IR analysis. Optimized geometry, first-order molecular hyperpolarizability (β), polarizability (α), bond length, bond angles and excited state energy from theoretical UV were derived by Hartree-Fock calculations. The complete assignment of the vibrational modes for 4-aminobenzophenonium picrate was performed by the scaled quantum mechanics force field (SQMFF) methodology using potential energy distribution. Natural bond orbital (NBO) calculations were employed to study the stabilities arising from charge delocalization and intermolecular interactions of 4ABPP. The atomic charge distributions of the various atoms present in 4ABPP are obtained by Mulliken charge population analysis. The as-grown crystal is further characterized by thermal and optical absorbance studies.

Exploratory use of cardiovascular magnetic resonance imaging in liver transplantation: a one-stop shop for preoperative cardiohepatic evaluation.

PubMed

Reddy, Sahadev T; Thai, Ngoc L; Fakhri, Asghar A; Oliva, Jose; Tom, Kusum B; Dishart, Michael K; Doyle, Mark; Yamrozik, June A; Williams, Ronald B; Grant, Saundra B; Poydence, Jacqueline; Shah, Moneal; Singh, Anil; Nathan, Swami; Biederman, Robert W W

2013-11-15

Preoperative cardiovascular risk stratification in orthotopic liver transplantation candidates has proven challenging due to limitations of current noninvasive modalities. Additionally, the preoperative workup is logistically cumbersome and expensive given the need for separate cardiac, vascular, and abdominal imaging. We evaluated the feasibility of a "one-stop shop" in a magnetic resonance suite, performing assessment of cardiac structure, function, and viability, along with simultaneous evaluation of thoracoabdominal vasculature and liver anatomy. In this pilot study, patients underwent steady-state free precession sequences and stress cardiac magnetic resonance (CMR), thoracoabdominal magnetic resonance angiography, and abdominal magnetic resonance imaging (MRI) on a standard MRI scanner. Pharmacologic stress was performed using regadenoson, adenosine, or dobutamine. Viability was assessed using late gadolinium enhancement. Over 2 years, 51 of 77 liver transplant candidates (mean age, 56 years; 35% female; mean Model for End-stage Liver Disease score, 10.8; range, 6-40) underwent MRI. All referred patients completed standard dynamic CMR, 98% completed stress CMR, 82% completed late gadolinium enhancement for viability, 94% completed liver MRI, and 88% completed magnetic resonance angiography. The mean duration of the entire study was 72 min, and 45 patients were able to complete the entire examination. Among all 51 patients, 4 required follow-up coronary angiography (3 for evidence of ischemia on perfusion CMR and 1 for postoperative ischemia), and none had flow-limiting coronary disease. Nine proceeded to orthotopic liver transplantation (mean 74 days to transplantation after MRI). There were six ascertained mortalities in the nontransplant group and one death in the transplanted group. Explant pathology confirmed 100% detection/exclusion of hepatocellular carcinoma. No complications during CMR examination were encountered. In this proof-of-concept study, it appears feasible to perform a comprehensive, efficient, and safe preoperative liver transplant imaging in a CMR suite-a one-stop shop, even in seriously ill patients.

Photogenerated radical intermediates of vitamin K 1: a time-resolved resonance Raman study

NASA Astrophysics Data System (ADS)

Balakrishnan, G.; Umapathy, S.

1999-01-01

Quinones play a vital role in the process of electron transfer in bacterial photosynthetic reaction centers. It is of interest to investigate the photochemical reactions involving quinones with a view to elucidating the structure-function relationships in the biological processes. Resonance Raman spectra of radical anions and the time-resolved resonance Raman spectra of vitamin K 1 (model compound for Q A in Rhodopseudomonas viridis, a bacterial photosynthetic reception center) are presented. The photochemical intermediates of vitamin K 1, viz. radical anion, ketyl radical and o-quinone methide have been identified. The vibrational assignments of all these intermediates are made on the basis of comparison with our earlier TR3 studies on radical anions of naphthoquinone and menaquinone.

36 CFR 51.88 - What happens if an assignment or encumbrance is completed without the approval of the Director?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR CONCESSION CONTRACTS Assignment or Encumbrance of Concession Contracts § 51.88 What happens if an assignment or encumbrance is... written approval of the Director will be considered as null and void and a material breach of the...

Coulomb and nuclear excitations of narrow resonances in 17Ne

DOE PAGES

Marganiec, J.; Wamers, F.; Aksouh, F.; ...

2016-05-25

New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the 15O+p +p three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of datamore » from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. Finally, the resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.« less

Structure, spectra and antioxidant action of ascorbic acid studied by density functional theory, Raman spectroscopic and nuclear magnetic resonance techniques.

PubMed

Singh, Gurpreet; Mohanty, B P; Saini, G S S

2016-02-15

Structure, vibrational and nuclear magnetic resonance spectra, and antioxidant action of ascorbic acid towards hydroxyl radicals have been studied computationally and in vitro by ultraviolet-visible, nuclear magnetic resonance and vibrational spectroscopic techniques. Time dependant density functional theory calculations have been employed to specify various electronic transitions in ultraviolet-visible spectra. Observed chemical shifts and vibrational bands in nuclear magnetic resonance and vibrational spectra, respectively have been assigned with the help of calculations. Changes in the structure of ascorbic acid in aqueous phase have been examined computationally and experimentally by recording Raman spectra in aqueous medium. Theoretical calculations of the interaction between ascorbic acid molecule and hydroxyl radical predicted the formation of dehydroascorbic acid as first product, which has been confirmed by comparing its simulated spectra with the corresponding spectra of ascorbic acid in presence of hydrogen peroxide. Copyright © 2015 Elsevier B.V. All rights reserved.

Study of D J meson decays to D +π-, D 0π+ and D ∗+π- final states in pp collisions

NASA Astrophysics Data System (ADS)

Aaij, R.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Baesso, C.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Burducea, I.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Campana, P.; Perez, D. Campora; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chen, P.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; David, P.; David, P. N. Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Dogaru, M.; Donleavy, S.; Dordei, F.; Suárez, A. Dosil; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Ferguson, D.; Albor, V. Fernandez; Rodrigues, F. Ferreira; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Furfaro, E.; Torreira, A. Gallas; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Tico, J. Garra; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Gándara, M. Grabalosa; Diaz, R. Graciani; Cardoso, L. A. Granado; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Morata, J. A. Hernando; van Herwijnen, E.; Hicheur, A.; Hicks, E.; Hill, D.; Hoballah, M.; Hombach, C.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Ketel, T.; Keune, A.; Khanji, B.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Gioi, L. Li; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.; Manca, G.; Mancinelli, G.; Maratas, J.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Sánchez, A. M´ın; Martinelli, M.; Santos, D. Martinez; Tostes, D. Martins; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Maurice, E.; Mazurov, A.; Skelly, B. Mc; McCarthy, J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Rodriguez, J. Molina; Monteil, S.; Moran, D.; Morawski, P.; Mordà, A.; Morello, M. J.; Mountain, R.; Mous, I.; Muheim, F.; Müller, K.; Muresan, R.; Muryn, B.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neubert, S.; Neufeld, N.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Nomerotski, A.; Novoselov, A.; Oblakowska-Mucha, A.; Obraztsov, V.; Oggero, S.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Orlandea, M.; Goicochea, J. M. Otalora; Owen, P.; Oyanguren, A.; Pal, B. K.; Palano, A.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrick, G. N.; Patrignani, C.; Pavel-Nicorescu, C.; Alvarez, A. Pazos; Pellegrino, A.; Penso, G.; Altarelli, M. Pepe; Perazzini, S.; Trigo, E. Perez; Yzquierdo, A. Pérez-Calero; Perret, P.; Perrin-Terrin, M.; Pessina, G.; Petridis, K.; Petrolini, A.; Phan, A.; Olloqui, E. Picatoste; Pietrzyk, B.; Pilař, T.; Pinci, D.; Playfer, S.; Casasus, M. Plo; Polci, F.; Polok, G.; Poluektov, A.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Powell, A.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Navarro, A. Puig; Punzi, G.; Qian, W.; Rademacker, J. H.; Rakotomiaramanana, B.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redford, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, A.; Rinnert, K.; Molina, V. Rives; Romero, D. A. Roa; Robbe, P.; Roberts, D. A.; Rodrigues, E.; Perez, P. Rodriguez; Roiser, S.; Romanovsky, V.; Vidal, A. Romero; Rouvinet, J.; Ruf, T.; Ruffini, F.; Ruiz, H.; Valls, P. Ruiz; Sabatino, G.; Silva, J. J. Saborido; Sagidova, N.; Sail, P.; Saitta, B.; Guimaraes, V. Salustino; Salzmann, C.; Sedes, B. Sanmartin; Sannino, M.; Santacesaria, R.; Rios, C. Santamarina; Santovetti, E.; Sapunov, M.; Sarti, A.; Satriano, C.; Satta, A.; Savrie, M.; Savrina, D.; Schaack, P.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Seco, M.; Semennikov, A.; Senderowska, K.; Sepp, I.; Serra, N.; Serrano, J.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shatalov, P.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Coutinho, R. Silva; Sirendi, M.; Skwarnicki, T.; Smith, N. A.; Smith, E.; Smith, J.; Smith, M.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; De Paula, B. Souza; Spaan, B.; Sparkes, A.; Spradlin, P.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Straticiuc, M.; Straumann, U.; Subbiah, V. K.; Sun, L.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Teodorescu, E.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Tolk, S.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, M. T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Garcia, M. Ubeda; Ukleja, A.; Urner, D.; Ustyuzhanin, A.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vallier, A.; Van Dijk, M.; Gomez, R. Vazquez; Regueiro, P. Vazquez; Sierra, C. Vázquez; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; Waldi, R.; Wallace, C.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Webber, A. D.; Websdale, D.; Whitehead, M.; Wicht, J.; Wiechczynski, J.; Wiedner, D.; Wiggers, L.; Wilkinson, G.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Witek, M.; Wotton, S. A.; Wright, S.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Young, R.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, F.; Zhang, L.; Zhang, W. C.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zvyagin, A.

2013-09-01

A study of D +π-, D 0π+ and D ∗+π- final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 fb-1, collected at a centre-of-mass energy of 7 TeV with the LHCb detector. The D 1(2420)0 resonance is observed in the D ∗+π- final state and the resonance is observed in the D +π-, D 0π+ and D ∗+π- final states. For both resonances, their properties and spin-parity assignments are obtained. In addition, two natural parity and two unnatural parity resonances are observed in the mass region between 2500 and 2800 MeV. Further structures in the region around 3000 MeV are observed in all the D ∗+π-, D +π- and D 0π+ final states. [Figure not available: see fulltext.

Origin of the positive spin- 1 2 photoluminescence-detected magnetic resonance in π-conjugated materials and devices

DOE PAGES

Chen, Ying; Cai, Min; Hellerich, Emily; ...

2015-09-02

The spin-1/2 single-modulation (SM) and double-modulation (DM) photoluminescence (PL) detected magnetic resonance (PLDMR) in poly(2-methoxy-5-(2'-ethyl)–hexoxy-1,4- phenylene vinylene) (MEH-PPV) films and poly(3-hexylthiophene) (P3HT) films is described, analyzed, and discussed. In particular, the models based on spin-dependent recombination of charge pairs (SDR) and triplet-polaron quenching (TPQ) are evaluated. By analyzing the dependence of the resonance amplitude on the microwave chopping (modulation) frequency using rate equations, it is demonstrated that the TPQ model can well explain the observed resonance behavior, while SDR model cannot reproduce the results of the observed DM-PLDMR. As a result, the observed spin-1/2 PLDMR is assigned to TPQ rathermore » than SDR, even though the latter may also be present.« less

7-epi-griffonilide, a new lactone from Bauhinia pentandra: complete 1H and 13C chemical shift assignments.

PubMed

Almeida, Macia C S DE; Souza, Luciana G S; Ferreira, Daniele A; Pinto, Francisco C L; Oliveira, Débora R DE; Santiago, Gilvandete M P; Monte, Francisco J Q; Braz-Filho, Raimundo; Lemos, Telma L G DE

2017-01-01

A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.

Photoabsorption and S 2p photoionization of the SF6 molecule: resonances in the excitation energy range of 200-280 eV.

PubMed

Stener, M; Bolognesi, P; Coreno, M; O'Keeffe, P; Feyer, V; Fronzoni, G; Decleva, P; Avaldi, L; Kivimäki, A

2011-05-07

Photoabsorption and S 2p photoionization of the SF(6) molecule have been studied experimentally and theoretically in the excitation energy range up to 100 eV above the S 2p ionization potentials. In addition to the well-known 2t(2g) and 4e(g) shape resonances, the spin-orbit-resolved S 2p photoionization cross sections display two weak resonances between 200 and 210 eV, a wide resonance around 217 eV, a Fano-type resonance around 240 eV, and a second wide resonance around 260 eV. Calculations based on time-dependent density functional theory allow us to assign the 217-eV and 260-eV features to the shape resonances in S 2p photoionization. The Fano resonance is caused by the interference between the direct S 2p photoionization channel and the resonant channel that results from the participator decay of the S 2s(-1)6t(1u) excited state. The weak resonances below 210-eV photon energy, not predicted by theory, are tentatively suggested to originate from the coupling between S 2p shake-up photoionization and S 2p single-hole photoionization. The experimental and calculated angular anisotropy parameters for S 2p photoionization are in good agreement.

Complete virilization in congenital adrenal hyperplasia: clinical course, medical management and disease-related complications.

PubMed

Woelfle, J; Hoepffner, W; Sippell, W G; Brämswig, J H; Heidemann, P; Deiss, D; Bökenkamp, A; Roth, C; Irle, U; Wollmann, H A; Zachmann, M; Kubini, K; Albers, N

2002-02-01

In girls with congenital adrenal hyperplasia (CAH), genital ambiguity usually leads to a rapid neonatal diagnosis. Rarely, CAH causes complete virilization and male sex assignment with a delayed diagnosis. After being confronted with very specific problems in two of such patients, we collected data of patients with CAH and complete virilization in a nationwide study to delineate specific problems of these rare patients in order to improve their management. Through the German Working Group of Paediatric Endocrinology (Arbeitsgemeinschaft Pädiatrische Endokrinologie, APE), questionnaires were sent to all members caring for patients with CAH and complete virilization in their endocrine clinics. Data from 16 patients from 10 paediatric endocrine centres were assessed by questionnaire. The following problems have been encountered. (1) Sex assignment/gender identity: initially all patients had a male sex assignment. Six patients were diagnosed during the first month of life. Five were reassigned to female sex immediately, one at the age of 19 months. Except in one girl demonstrating some tomboyish behaviour, gender role behaviour in these patients did not differ from unaffected girls. Ten patients were diagnosed late at 3.4--7 years of age. In seven patients with a late diagnosis, male sex assignment was maintained; one of them expressed some concerns about living as a male. In three patients late sex reversal was performed, gender identity is very poor in one and new sex assignment is currently under consideration. (2) SURGERY: irrespective of the sex assigned, all patients had between one and three surgical procedures, including clitoris reduction and (repeated) vaginoplasties in patients with female sex assignment. Hysterectomy and ovarectomy were performed in patients with male sex assignment. (3) Short stature: patients with a late diagnosis of CAH had extremely advanced bone ages of +6.3 to +9.5 years, leading to severely reduced final height of 137 to 150 cm in adult patients. Patients tended to follow height percentiles of genetic females. One pubertal patient was suicidal due to short stature. (4) Central precocious puberty (CPP): prolonged exposition to adrenal androgens led to CPP in one patient. He was treated with GnRH analogues until gonadectomy. Patients with CAH and complete virilization have a high risk of being diagnosed late. There are major problems and uncertainties of the patients' families and the treating physicians concerning gender assignment. Gender identity is disturbed in some patients. In addition, multiple surgical procedures are necessary and short stature as well as central precocious puberty might be important to avoid late sequelae. While some surgical interventions are probably unavoidable, most of these issues could be resolved with an early diagnosis. Thus, especially for these patients, a neonatal screening programme for CAH would be of paramount importance.

Family homework and school-based sex education: delaying early adolescents' sexual behavior.

PubMed

Grossman, Jennifer M; Frye, Alice; Charmaraman, Linda; Erkut, Sumru

2013-11-01

Early sexual activity can undermine adolescents' future school success and health outcomes. The purpose of this study was to assess the role of a family homework component of a comprehensive sex education intervention in delaying sexual initiation for early adolescents and to explore what social and contextual factors prevent adolescents from completing these family homework activities. This mixed methods study included 6th- and 7th-grade survey responses from 706 students at 11 middle school schools receiving a sex education intervention, as well as interviews from a subset of 33, 7th-grade students from the larger sample. Adolescents who completed more family homework assignments were less likely to have vaginal intercourse in 7th grade than those who completed fewer assignments, after controlling for self-reports of having had vaginal intercourse in 6th grade and demographic variables. Participants' explanations for not completing assignments included personal, curriculum, and family-based reasons. Family homework activities designed to increase family communication about sexual issues can delay sex among early adolescents and contribute to school-based sex education programs. Successful sex education programs must identify and address barriers to family homework completion. © 2013, American School Health Association.

Formularity: Software for Automated Formula Assignment of Natural and Other Organic Matter from Ultrahigh-Resolution Mass Spectra.

PubMed

Tolić, Nikola; Liu, Yina; Liyu, Andrey; Shen, Yufeng; Tfaily, Malak M; Kujawinski, Elizabeth B; Longnecker, Krista; Kuo, Li-Jung; Robinson, Errol W; Paša-Tolić, Ljiljana; Hess, Nancy J

2017-12-05

Ultrahigh resolution mass spectrometry, such as Fourier transform ion cyclotron resonance mass spectrometry (FT ICR MS), can resolve thousands of molecular ions in complex organic matrices. A Compound Identification Algorithm (CIA) was previously developed for automated elemental formula assignment for natural organic matter (NOM). In this work, we describe software Formularity with a user-friendly interface for CIA function and newly developed search function Isotopic Pattern Algorithm (IPA). While CIA assigns elemental formulas for compounds containing C, H, O, N, S, and P, IPA is capable of assigning formulas for compounds containing other elements. We used halogenated organic compounds (HOC), a chemical class that is ubiquitous in nature as well as anthropogenic systems, as an example to demonstrate the capability of Formularity with IPA. A HOC standard mix was used to evaluate the identification confidence of IPA. Tap water and HOC spike in Suwannee River NOM were used to assess HOC identification in complex environmental samples. Strategies for reconciliation of CIA and IPA assignments were discussed. Software and sample databases with documentation are freely available.

Basic Vision Events.

DTIC Science & Technology

1982-08-01

6 4 Resonance Raman Spectrum of Astaxanthin .............................. 8 5 Excitation Profile of CC1 4...Solution of Astaxanthin ........................ 9 LIST OF TABLES Table Page I Suggested Vibrational Assignments Frequencies (cm- 1...past year. These measurements on the carotenoid, astaxanthin , showed an alteration in the C=C stretching vibration from 1517 cm ŕ , under the action

Do It Right! Requiring Multiple Submissions of Math and NMR Analysis Assignments in the Laboratory

ERIC Educational Resources Information Center

Slade, David J.

2017-01-01

The first-semester introductory organic chemistry laboratory has been adapted to include mini postlab assignments that students must complete correctly, through as many attempts as prove to be necessary. The use of multiple drafts of writing assignments is a standard approach to improving writing, so the system was designed to require drafts for…

When the Due Date Is Not the "Do" Date!

ERIC Educational Resources Information Center

Mastrianni, Theresa M.

2015-01-01

Our students consistently hand in assignments late, or complete them at the last minute. Why is it that they know about assignments all term long yet only begin them the night before the assignment is due? Based on a career-focused learning community at Kingsborough Community College of the City University of New York, this article looks at ways…

Preparing a prescription drug monitoring program data set for research purposes.

PubMed

O'Kane, Nicole; Hallvik, Sara E; Marino, Miguel; Van Otterloo, Joshua; Hildebran, Christi; Leichtling, Gillian; Deyo, Richard A

2016-09-01

To develop a complete and consistent prescription drug monitoring program (PDMP) data set for use by drug safety researchers in evaluating patterns of high-risk use and potential abuse of scheduled drugs. Using publically available data references from the US Food and Drug Administration and the Centers for Disease Control and Prevention, we developed a strategic methodology to assign drug categories based on pharmaceutical class for the majority of prescriptions in the PDMP data set. We augmented data elements required to calculate morphine milligram equivalents and assigned duration of action (short-acting or long acting) properties for a majority of opioids in the data set. About 10% of prescriptions in the PDMP data set did not have a vendor-assigned drug category, and 20% of opioid prescriptions were missing data needed to calculate risk metrics. Using inclusive methods, 19 133 167 (>99.9%) of prescriptions in the PDMP data set were assigned a drug category. For the opioid category, augmenting data elements resulted in 10 760 669 (99.8%) having required values to calculate morphine milligram equivalents and evaluate duration of action properties. Drug safety researchers who require a complete and consistent PDMP data set can use the methods described here to ensure that prescriptions of interest are assigned consistent drug categories and complete opioid risk variable values. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Integral resonator gyroscope

NASA Technical Reports Server (NTRS)

Shcheglov, Kirill V. (Inventor); Challoner, A. Dorian (Inventor); Hayworth, Ken J. (Inventor); Wiberg, Dean V. (Inventor); Yee, Karl Y. (Inventor)

2008-01-01

The present invention discloses an inertial sensor having an integral resonator. A typical sensor comprises a planar mechanical resonator for sensing motion of the inertial sensor and a case for housing the resonator. The resonator and a wall of the case are defined through an etching process. A typical method of producing the resonator includes etching a baseplate, bonding a wafer to the etched baseplate, through etching the wafer to form a planar mechanical resonator and the wall of the case and bonding an end cap wafer to the wall to complete the case.

Method of producing an integral resonator sensor and case

NASA Technical Reports Server (NTRS)

Challoner, A. Dorian (Inventor); Yee, Karl Y. (Inventor); Shcheglov, Kirill V. (Inventor); Hayworth, Ken J. (Inventor); Wiberg, Dean V. (Inventor)

2005-01-01

The present invention discloses an inertial sensor having an integral resonator. A typical sensor comprises a planar mechanical resonator for sensing motion of the inertial sensor and a case for housing the resonator. The resonator and a wall of the case are defined through an etching process. A typical method of producing the resonator includes etching a baseplate, bonding a wafer to the etched baseplate, through etching the wafer to form a planar mechanical resonator and the wall of the case and bonding an end cap wafer to the wall to complete the case.

Elastic alpha-particle resonances as evidence of clustering at high excitation in 40Ca

NASA Astrophysics Data System (ADS)

Norrby, M.; Lönnroth, T.; Goldberg, V. Z.; Rogachev, G. V.; Golovkov, M. S.; Källman, K.-M.; Lattuada, M.; Perov, S. V.; Romano, S.; Skorodumov, B. B.; Tiourin, G. P.; Trzaska, W. H.; Tumino, A.; Vorontsov, A. N.

2011-08-01

The elastic-scattering reaction 36Ar + α was studied using the Thick Target Inverse Kinematics technique. Data were taken at a beam energy of 150 MeV in a reaction chamber filled with 4He gas, corresponding to the excitation region of 12-20 MeV in 40Ca. Using a simplified R -matrix method of analysis energies, widths and spin assignments were obtained for 137 resonances. The structure is discussed within the concept of α-cluster structure in the quasi-continuum of 40Ca and is compared to other nuclei in the same mass region.

Transition of lasing modes in polymeric opal photonic crystal resonating cavity.

PubMed

Shi, Lan-Ting; Zheng, Mei-Ling; Jin, Feng; Dong, Xian-Zi; Chen, Wei-Qiang; Zhao, Zhen-Sheng; Duan, Xuan-Ming

2016-06-10

We demonstrate the transition of lasing modes in the resonating cavity constructed by polystyrene opal photonic crystals and 7 wt. % tert-butyl Rhodamine B doped polymer film. Both single mode and multiple mode lasing emission are observed from the resonating cavity. The lasing threshold is determined to be 0.81  μJ/pulse for single mode lasing emission and 2.25  μJ/pulse for multiple mode lasing emission. The single mode lasing emission is attributed to photonic lasing resulting from the photonic bandgap effect of the opal photonic crystals, while the multiple mode lasing emission is assigned to random lasing due to the defects in the photonic crystals. The result would benefit the development of low threshold polymeric solid state photonic crystal lasers.

Identification of the Ga interstitial in Al(x)Ga(1-x)As by optically detected magnetic resonance

NASA Technical Reports Server (NTRS)

Kennedy, T. A.; Spencer, M. G.

1986-01-01

A new optically detected magnetic resonance spectrum in Al(x)Ga(1-x)As is reported and assigned to native Ga interstitials. Luminescence-quenching signals were observed over the energy region from 0.75 to 1.1 eV. The optically detected magnetic resonance is nearly isotropic, with spin-Hamiltonian parameters g = 2.025 + or - 0.006, central hyperfine splitting A(Ga-69) = 0.050 + or - 0.001/cm, and A(Ga-71) = 0.064 + or - 0.001/cm for H near the 001 line. The strong hyperfine coupling denotes an electronic state of A1 symmetry, which current theories predict for the Ga interstitial but not the Ga antisite. The slight anisotropy probably indicates that the Ga(i) is paired with a second, unknown defect.

Scissors Mode of 162 Dy Studied from Resonance Neutron Capture

DOE PAGES

Baramsai, B.; Bečvář, F.; Bredeweg, T. A.; ...

2015-05-28

Multi-step cascade γ-ray spectra from the neutron capture at isolated resonances of 161Dy nucleus were measured at the LANSCE/DANCE time-of-flight facility in Los Alamos National Laboratory. The objectives of this experiment were to confirm and possibly extend the spin assignment of s-wave neutron resonances and get new information on photon strength functions with emphasis on the role of the M1 scissors mode vibration. The preliminary results show that the scissors mode plays a significant role in all transitions between accessible states of the studied nucleus. The photon strength functions describing well our data are compared to results from 3He-induced reactions,more » (n,γ) experiments on Gd isotopes, and (γ,γ’) reactions.« less

Nonlinear resonance ultrasonic vibrations in Czochralski-silicon wafers

NASA Astrophysics Data System (ADS)

Ostapenko, S.; Tarasov, I.

2000-04-01

A resonance effect of generation of subharmonic acoustic vibrations is observed in as-grown, oxidized, and epitaxial silicon wafers. Ultrasonic vibrations were generated into a standard 200 mm Czochralski-silicon (Cz-Si) wafer using a circular ultrasound transducer with major frequency of the radial vibrations at about 26 kHz. By tuning frequency (f) of the transducer within a resonance curve, we observed a generation of intense f/2 subharmonic acoustic mode assigned as a "whistle." The whistle mode has a threshold amplitude behavior and narrow frequency band. The whistle is attributed to a nonlinear acoustic vibration of a silicon plate. It is demonstrated that characteristics of the whistle mode are sensitive to internal stress and can be used for quality control and in-line diagnostics of oxidized and epitaxial Cz-Si wafers.

Measuring Homework Completion in Behavioral Activation

ERIC Educational Resources Information Center

Busch, Andrew M.; Uebelacker, Lisa A.; Kalibatseva, Zornitsa; Miller, Ivan W.

2010-01-01

The aim of this study was to develop and validate an observer-based coding system for the characterization and completion of homework assignments during Behavioral Activation (BA). Existing measures of homework completion are generally unsophisticated, and there is no current measure of homework completion designed to capture the particularities…

Embracing Alter-Identities: Socio-Cultural Development for Graduate Education

ERIC Educational Resources Information Center

Hains, Bryan J.; Tubbs, Jonathan; Vincent, Stacy K.

2013-01-01

This qualitative case study examines one faculty member's approach toward instilling culturally immersive experiences into graduate curriculum. Participants completed course assignments designed to enhance their multicultural understanding and competence. Course assignments culminated in an immersive experience where students embodied an…

46 CFR 310.59 - Courses of instruction.

Code of Federal Regulations, 2011 CFR

2011-10-01

... science courses prescribed by the Department of the Navy. All curriculums include general education... Academy. Three major curriculums are offered: Nautical Science, for the preparation of deck officers... addition to practical shipboard assignments, midshipmen are required to complete written study assignments...

Phase modulated 2D HSQC-TOCSY for unambiguous assignment of overlapping spin systems

NASA Astrophysics Data System (ADS)

Singh, Amrinder; Dubey, Abhinav; Adiga, Satish K.; Atreya, Hanudatta S.

2018-01-01

We present a new method that allows one to unambiguously resolve overlapping spin systems often encountered in biomolecular systems such as peptides and proteins or in samples containing a mixture of different molecules such as in metabolomics. We address this problem using the recently proposed phase modulation approach. By evolving the 1H chemical shifts in a conventional two dimensional (2D) HSQC-TOCSY experiment for a fixed delay period, the phase/intensity of set of cross peaks belonging to one spin system are modulated differentially relative to those of its overlapping counterpart, resulting in their discrimination and recognition. The method thus accelerates the process of identification and resonance assignment of individual compounds in complex mixtures. This approach facilitated the assignment of molecules in the embryo culture medium used in human assisted reproductive technology.

The Reduction of a Nitrile (CN) Group by Sodium Borohydride. The Preparation of Phosphine--Amine and Phosphine--Iimidate Complesex of Tungsten Carbonyl.

ERIC Educational Resources Information Center

Faust, Kristen E.; Storhoff, Bruce N.

1989-01-01

Describes an experiment for advanced-level undergraduate students for extending student experiences involving recording and interpreting infrared (IR) and nuclear magnetic resonance (NMR) spectra from reactions of organometallic compounds. Experimental procedures, analyses and structural assignments, and suggestions for extension and modification…

The neural substrates of in-group bias: a functional magnetic resonance imaging investigation.

PubMed

Van Bavel, Jay J; Packer, Dominic J; Cunningham, William A

2008-11-01

Classic minimal-group studies found that people arbitrarily assigned to a novel group quickly display a range of perceptual, affective, and behavioral in-group biases. We randomly assigned participants to a mixed-race team and used functional magnetic resonance imaging to identify brain regions involved in processing novel in-group and out-group members independently of preexisting attitudes, stereotypes, or familiarity. Whereas previous research on intergroup perception found amygdala activity--typically interpreted as negativity--in response to stigmatized social groups, we found greater activity in the amygdala, fusiform gyri, orbitofrontal cortex, and dorsal striatum when participants viewed novel in-group faces than when they viewed novel out-group faces. Moreover, activity in orbitofrontal cortex mediated the in-group bias in self-reported liking for the faces. These in-group biases in neural activity were not moderated by race or by whether participants explicitly attended to team membership or race, a finding suggesting that they may occur automatically. This study helps clarify the role of neural substrates involved in perceptual and affective in-group biases.

The {sup 17}F(p,{gamma}){sup 18}Ne3{sup +} resonance state studied with the {sup 16}O({sup 3}He,n){sup 18}Ne reaction

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

Parpottas, Y.; Grimes, S.M.; Brune, C.R.

2005-08-01

The astrophysically important 3{sup +} resonance of the {sup 17}F(p,{gamma}){sup 18}Ne reaction has been studied with the {sup 16}O({sup 3}He,n){sup 18}Ne reaction. High-resolution measurements were carried out for three different kinematic configurations. We find an excitation energy of 4527(4) keV and a proton width of 17(4) keV for the 3{sup +} state. Measured differential cross sections were compared with Hauser-Feshbach predictions to assign the spin of the 4527-keV state and confirm the spin assignments of the two known levels in this region. Our results differ from the earlier {sup 16}O({sup 3}He,n){sup 18}Ne findings of Garcia et al. [Phys. Rev. Cmore » 43, 2012 (1991)], but they agree well with the {sup 17}F(p,p){sup 17}F measurements of Bardayan et al. [Phys. Rev. C 62, 055804 (2002)].« less

A comparative study of the hydrogen-bonding patterns and prototropism in solid 2-thiocytosine (potential antileukemic agent) and cytosine, as studied by 1H-14N NQDR and QTAIM/ DFT.

PubMed

Latosińska, Jolanta N; Seliger, Janez; Zagar, Veselko; Burchardt, Dorota V

2012-01-01

A potential antileukemic and anticancer agent, 2-thiocytosine (2-TC), has been studied experimentally in the solid state by (1)H-(14)N NMR-NQR double resonance (NQDR) and theoretically by the quantum theory of atoms in molecules (QTAIM)/density functional theory (DFT). Eighteen resonance frequencies on (14)N were detected at 180 K and assigned to particular nitrogen sites (-NH(2), -N=, and -NH-) in 2-thiocytosine. Factors such as the nonequivalence of molecules (connected to the duplication of sites) and possible prototropic tautomerism (capable of modifying the type of site due to proton transfer) were taken into account during frequency assignment. The result of replacing oxygen with sulfur, which leads to changes in the intermolecular interaction pattern and molecular aggregation, is discussed. This study demonstrates the advantages of combining NQDR and DFT to extract detailed information on the H-bonding properties of crystals with complex H-bonding networks. Solid-state properties were found to have a profound impact on the stabilities and reactivities of both compounds.

Establishment of the purity values of carbohydrate certified reference materials using quantitative nuclear magnetic resonance and mass balance approach.

PubMed

Quan, Can

2014-06-15

This work described the assignment of purity values to six carbohydrate certified reference materials, including glucose, fructose, galactose, lactose, xylose and sucrose, according to the ISO Guides 34 and 35. The CRMs' purity values were assigned based on the weighted average of quantitative nuclear magnetic resonance method and mass balance approach with high resolution liquid chromatography - evaporative light scattering detection. All the six CRMs with following value amount fractions: glucose (GBW10062) at a certified purity P ± U (k=2) of (0.99 ± 0.005)%; fructose (GBW10063) at (0.99 ± 0.005)%; galactose (GBW10064) at (0.99 ± 0.007)%; lactose (GBW10065) at (0.99 ± 0.008)%; xylose (GBW10066) at (0.99 ± 0.007)% and sucrose (GBW10067) at (0.99 ± 0.008)%, respectively were certified. The homogeneity of the CRMs was determined by an in-house validated liquid chromatographic method. Potential degradation during storage was also investigated and a shelf-life based on this value was established. Copyright © 2013 Elsevier Ltd. All rights reserved.

Distribution functions for resonantly trapped orbits in the Galactic disc

NASA Astrophysics Data System (ADS)

Monari, Giacomo; Famaey, Benoit; Fouvry, Jean-Baptiste; Binney, James

2017-11-01

The present-day response of a Galactic disc stellar population to a non-axisymmetric perturbation of the potential has previously been computed through perturbation theory within the phase-space coordinates of the unperturbed axisymmetric system. Such an Eulerian linearized treatment, however, leads to singularities at resonances, which prevent quantitative comparisons with data. Here, we manage to capture the behaviour of the distribution function (DF) at a resonance in a Lagrangian approach, by averaging the Hamiltonian over fast angle variables and re-expressing the DF in terms of a new set of canonical actions and angles variables valid in the resonant region. We then follow the prescription of Binney, assigning to the resonant DF the time average along the orbits of the axisymmetric DF expressed in the new set of actions and angles. This boils down to phase-mixing the DF in terms of the new angles, such that the DF for trapped orbits depends only on the new set of actions. This opens the way to quantitatively fitting the effects of the bar and spirals to Gaia data in terms of DFs in action space.

QPO observations related to neutron star equations of state

NASA Astrophysics Data System (ADS)

Stuchlik, Zdenek; Urbanec, Martin; Török, Gabriel; Bakala, Pavel; Cermak, Petr

We apply a genetic algorithm method for selection of neutron star models relating them to the resonant models of the twin peak quasiperiodic oscillations observed in the X-ray neutron star binary systems. It was suggested that pairs of kilo-hertz peaks in the X-ray Fourier power density spectra of some neutron stars reflect a non-linear resonance between two modes of accretion disk oscillations. We investigate this concept for a specific neutron star source. Each neutron star model is characterized by the equation of state (EOS), rotation frequency Ω and central energy density ρc . These determine the spacetime structure governing geodesic motion and position dependent radial and vertical epicyclic oscillations related to the stable circular geodesics. Particular kinds of resonances (KR) between the oscillations with epicyclic frequencies, or the frequencies derived from them, can take place at special positions assigned ambiguously to the spacetime structure. The pairs of resonant eigenfrequencies relevant to those positions are therefore fully given by KR,ρc , Ω, EOS and can be compared to the observationally determined pairs of eigenfrequencies in order to eliminate the unsatisfactory sets (KR,ρc , Ω, EOS). For the elimination we use the advanced genetic algorithm. Genetic algorithm comes out from the method of natural selection when subjects with the best adaptation to assigned conditions have most chances to survive. The chosen genetic algorithm with sexual reproduction contains one chromosome with restricted lifetime, uniform crossing and genes of type 3/3/5. For encryption of physical description (KR,ρ, Ω, EOS) into chromosome we used Gray code. As a fitness function we use correspondence between the observed and calculated pairs of eigenfrequencies.

Neutron star equation of state and QPO observations

NASA Astrophysics Data System (ADS)

Urbanec, Martin; Stuchlík, Zdeněk; Török, Gabriel; Bakala, Pavel; Čermák, Petr

2007-12-01

Assuming a resonant origin of the twin peak quasiperiodic oscillations observed in the X-ray neutron star binary systems, we apply a genetic algorithm method for selection of neutron star models. It was suggested that pairs of kilohertz peaks in the X-ray Fourier power density spectra of some neutron stars reflect a non-linear resonance between two modes of accretion disk oscillations. We investigate this concept for a specific neutron star source. Each neutron star model is characterized by the equation of state (EOS), rotation frequency Ω and central energy density rho_{c}. These determine the spacetime structure governing geodesic motion and position dependent radial and vertical epicyclic oscillations related to the stable circular geodesics. Particular kinds of resonances (KR) between the oscillations with epicyclic frequencies, or the frequencies derived from them, can take place at special positions assigned ambiguously to the spacetime structure. The pairs of resonant eigenfrequencies relevant to those positions are therefore fully given by KR, rho_{c}, Ω, EOS and can be compared to the observationally determined pairs of eigenfrequencies in order to eliminate the unsatisfactory sets (KR, rho_{c}, Ω, EOS). For the elimination we use the advanced genetic algorithm. Genetic algorithm comes out from the method of natural selection when subjects with the best adaptation to assigned conditions have most chances to survive. The chosen genetic algorithm with sexual reproduction contains one chromosome with restricted lifetime, uniform crossing and genes of type 3/3/5. For encryption of physical description (KR, rho_{c}, Ω, EOS) into the chromosome we use the Gray code. As a fitness function we use correspondence between the observed and calculated pairs of eigenfrequencies.

Vibrational spectrum of the K-590 intermediate in the bacteriorhodopsin photocycle at room temperature: picosecond time-resolved resonance coherent anti-Raman spectroscopy

NASA Astrophysics Data System (ADS)

Ujj, L.; Jäger, F.; Popp, A.; Atkinson, G. H.

1996-12-01

The vibrational spectrum of the K-590 intermediate, thought to contribute significantly to the energy storage and transduction mechanism in the bacteriorhodopsin (BR) photocycle, is measured at room temperature using picosecond time-resolved resonance coherent anti-Stokes Raman scattering (PTR/CARS). The room-temperature BR photocycle is initiated by the 3 ps, 570 nm excitation of the ground-state species, BR-570, prepared in both H 2O and D 2O suspensions of BR. PTR/CARS data, recorded 50 ps after BR-570 excitation, at which time only BR-570 and K-590 are present, have an excellent S/N which provides a significantly more detailed view of the K-590 vibrational degrees of freedom than previously available. Two picosecond (6 ps FWHM) laser pulses, ω1 (633.4 nm) and ωS (675-700 nm), are used to record PTR/CARS data via electronic resonance enhancement in both BR-570 and K-590, each of which contains a distinct retinal structure (assigned as 13- rans, 15- anti, 13- cis, respectively). To obtain the vibrational spectrum of K-590 separately, the PTR/CARS spectra from the mixture of isomeric retinals is quantitatively analyzed in terms of third-order susceptibility ( η(3)) relationships. PTR/CARS spectra of K-590 recorded from both H 2O and D 2O suspensions of BR are compared with the analogous vibrational data obtained via spontaneous resonance Raman (RR) scattering at both low (77 K) and room temperature. Analyses of these vibrational spectra identify temperature-dependent effects and changes assignable to the substitution of deuterium at the Schiff-base nitrogen not previously reported.

Method for concurrent execution of primitive operations by dynamically assigning operations based upon computational marked graph and availability of data

NASA Technical Reports Server (NTRS)

Mielke, Roland V. (Inventor); Stoughton, John W. (Inventor)

1990-01-01

Computationally complex primitive operations of an algorithm are executed concurrently in a plurality of functional units under the control of an assignment manager. The algorithm is preferably defined as a computationally marked graph contianing data status edges (paths) corresponding to each of the data flow edges. The assignment manager assigns primitive operations to the functional units and monitors completion of the primitive operations to determine data availability using the computational marked graph of the algorithm. All data accessing of the primitive operations is performed by the functional units independently of the assignment manager.

32 CFR 253.6 - Procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... agency check (NAC), completed with favorable results, before being nominated for assignment with the...), Defense Investigative Service, for initiation of the NAC or BI, as appropriate. (e) Upon completion of the...

Detection of hydrogen dissolved in acrylonitrile butadiene rubber by 1H nuclear magnetic resonance

NASA Astrophysics Data System (ADS)

Nishimura, Shin; Fujiwara, Hirotada

2012-01-01

Rubber materials, which are used for hydrogen gas seal, can dissolve hydrogen during exposure in high-pressure hydrogen gas. Dissolved hydrogen molecules were detected by solid state 1H NMR of the unfilled vulcanized acrylonitrile butadiene rubber. Two signals were observed at 4.5 ppm and 4.8 ppm, which were assignable to dissolved hydrogen, in the 1H NMR spectrum of NBR after being exposed 100 MPa hydrogen gas for 24 h at room temperature. These signals were shifted from that of gaseous hydrogen molecules. Assignment of the signals was confirmed by quantitative estimation of dissolved hydrogen and peak area of the signals.

Jet-cooled laser-induced fluorescence spectroscopy of ScH: Observation of an Ω‧=2-Ω″=1 transition

NASA Astrophysics Data System (ADS)

Mukund, Sheo; Bhattacharyya, Soumen; Nakhate, S. G.

2014-11-01

New bands of scandium monohydride at origins 17,914.5 and 17,942.3 cm-1 have been observed in a jet-cooled beam with laser-induced fluorescence spectroscopy. Mass-selected resonant photoionization spectroscopy also confirmed the carrier of the band as ScH. The rotational analysis indicated that both transitions at 17,914.5 and 17,942.3 cm-1 are of Ω‧=2-Ω″=1 type with vibrational assignments (0,0) and (1,1) respectively. The assigned g3Φ2-a3Δ1 excitation is the first observed triplet-triplet transition in ScH.

3D Motions of Iron in Six-Coordinate {FeNO} 7 Hemes by Nuclear Resonance Vibration Spectroscopy [3-D Motions of Iron in Six-coordinate {FeNO} 7 Hemes by NRVS

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

Peng, Qian; Pavlik, Jeffrey W.; Silvernail, Nathan J.

The vibrational spectrum of a six-coordinate nitrosyl iron porphyrinate, monoclinic [Fe(T pFPP)(1-MeIm)(NO)] (T pFPP = tetra- para-fluorophenylporphyrin; 1-MeIm=1-methylimidazole), has been studied by oriented single-crystal nuclear resonance vibrational spectroscopy (NRVS). The crystal was oriented to give spectra perpendicular to the porphyrin plane and two in-plane spectra perpendicular or parallel to the projection of the FeNO plane. These enable assignment of the FeNO bending and stretching modes. The measurements reveal that the two in-plane spectra have substantial differences that result from the strongly bonded axial NO ligand. The direction of the in-plane iron motion is found to be largely parallel and perpendicularmore » to the projection of the bent FeNO on the porphyrin plane. The out-of-plane Fe-N-O stretching and bending modes are strongly mixed with each other, as well as with porphyrin ligand modes. The stretch is mixed with v 50 as was also observed for dioxygen complexes. The frequency of the assigned stretching mode of eight Fe-X-O (X= N, C, and O) complexes is correlated with the Fe XO bond lengths. The nature of highest frequency band at ≈560 cm -1 has also been examined in two additional new derivatives. Previously assigned as the Fe NO stretch (by resonance Raman), it is better described as the bend, as the motion of the central nitrogen atom of the FeNO group is very large. There is significant mixing of this mode. In conclusion, the results emphasize the importance of mode mixing; the extent of mixing must be related to the peripheral phenyl substituents.« less

3D Motions of Iron in Six-Coordinate {FeNO} 7 Hemes by Nuclear Resonance Vibration Spectroscopy [3-D Motions of Iron in Six-coordinate {FeNO} 7 Hemes by NRVS

DOE PAGES

Peng, Qian; Pavlik, Jeffrey W.; Silvernail, Nathan J.; ...

2016-03-21

The vibrational spectrum of a six-coordinate nitrosyl iron porphyrinate, monoclinic [Fe(T pFPP)(1-MeIm)(NO)] (T pFPP = tetra- para-fluorophenylporphyrin; 1-MeIm=1-methylimidazole), has been studied by oriented single-crystal nuclear resonance vibrational spectroscopy (NRVS). The crystal was oriented to give spectra perpendicular to the porphyrin plane and two in-plane spectra perpendicular or parallel to the projection of the FeNO plane. These enable assignment of the FeNO bending and stretching modes. The measurements reveal that the two in-plane spectra have substantial differences that result from the strongly bonded axial NO ligand. The direction of the in-plane iron motion is found to be largely parallel and perpendicularmore » to the projection of the bent FeNO on the porphyrin plane. The out-of-plane Fe-N-O stretching and bending modes are strongly mixed with each other, as well as with porphyrin ligand modes. The stretch is mixed with v 50 as was also observed for dioxygen complexes. The frequency of the assigned stretching mode of eight Fe-X-O (X= N, C, and O) complexes is correlated with the Fe XO bond lengths. The nature of highest frequency band at ≈560 cm -1 has also been examined in two additional new derivatives. Previously assigned as the Fe NO stretch (by resonance Raman), it is better described as the bend, as the motion of the central nitrogen atom of the FeNO group is very large. There is significant mixing of this mode. In conclusion, the results emphasize the importance of mode mixing; the extent of mixing must be related to the peripheral phenyl substituents.« less

Formularity: Software for Automated Formula Assignment of Natural and Other Organic Matter from Ultrahigh-Resolution Mass Spectra

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

Tolić, Nikola; Liu, Yina; Liyu, Andrey

Ultrahigh-resolution mass spectrometry, such as Fourier transform ion-cyclotron resonance mass spectrometry (FT-ICR MS), can resolve thousands of molecular ions in complex organic matrices. A Compound Identification Algorithm (CIA) was previously developed for automated elemental formula assignment for natural organic matter (NOM). In this work we describe a user friendly interface for CIA, titled Formularity, which includes an additional functionality to perform search of formulas based on an Isotopic Pattern Algorithm (IPA). While CIA assigns elemental formulas for compounds containing C, H, O, N, S, and P, IPA is capable of assigning formulas for compounds containing other elements. We used halogenatedmore » organic compounds (HOC), a chemical class that is ubiquitous in nature as well as anthropogenic systems, as an example to demonstrate the capability of Formularity with IPA. A HOC standard mix was used to evaluate the identification confidence of IPA. The HOC spike in NOM and tap water were used to assess HOC identification in natural and anthropogenic matrices. Strategies for reconciliation of CIA and IPA assignments are discussed. Software and sample databases with documentation are freely available from the PNNL OMICS software repository https://omics.pnl.gov/software/formularity.« less

Measurement of radiative proton capture on F 18 and implications for oxygen-neon novae reexamined

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

Akers, C.; Laird, A. M.; Fulton, B. R.

The rate of the F-18(p, gamma)Ne-19 reaction affects the final abundance of the gamma-ray observable radioisotope F-18, produced in novae. However, no successful measurement of this reaction exists and the rate used is calculated from incomplete information on the contributing resonances. Of the two resonances thought to play a significant role, one has a radiative width estimated from the assumed analogue state in the mirror nucleus, F-19. The second does not have an analogue state assignment at all, resulting in an arbitrary radiative width being assumed. Here, we report the first successful direct measurement of the F-18(p, gamma)Ne-19 reaction. Themore » strength of the 665 keV resonance (E-x = 7.076 MeV) is found to be over an order of magnitude weaker than currently assumed in nova models. Reaction rate calculations show that this resonance therefore plays no significant role in the destruction of F-18 at any astrophysical energy.« less

Bringing the Universe to the World: Lessons Learned from a Massive Open Online Class on Astronomy

NASA Astrophysics Data System (ADS)

Impey, C.; Wenger, M.; Formanek, M.; Buxner, S.

2016-12-01

This paper presents the results of a massive open online class (MOOC) on astronomy called Astronomy: Exploring Time and Space. The class was hosted by the web platform Coursera and ran for six weeks from February to May 2015. Coverage was designed to emphasise topics in astronomy where there has been rapid research progress, including large telescopes, exploration of the Solar System, the discovery of exoplanets, exotic end states of stars, and the frontiers of cosmology. The core content was nearly eighteen hours of video lectures, assessed by thirteen video lecture quizzes, three peer review writing assignments, and two online activities. Information on demographics and on the goals and motivations of the learners was gathered using standard Coursera entry and exit surveys and an external Science Literacy survey. A total of 25 379 people registered for the course, and most of them did not complete any assignments. About two-thirds of the 14 900 learners who opened the course lived outside the United States, distributed across 151 different countries. Out of 4275 participants who completed one or more assignments, 1607 passed the course, and a majority did so with a grade of 80% or higher. Those who completed the course were generally very satisfied with their experience and felt it met their learning goals. The people with the highest chance of completing the course tended to be in the range 40 to 60 years old, had a college education, and were either retired or working in professional fields. The strongest predictors of passing the course were to have completed the first written assignment or the first online activity.

High School Completion of In-School Suspension Students.

ERIC Educational Resources Information Center

Johnston, Joanne S.

1989-01-01

Examines the high school completion rate of students in the class of 1988 assigned to an inschool suspension (ISS) program at some time during their high school career. Clearly, ISS students are high risks for school completion, as shown by this study's less than 50 percent completion rate. Nonetheless, such programs are essential. (MLH)

Resonant Raman spectra of diindenoperylene thin films

NASA Astrophysics Data System (ADS)

Scholz, R.; Gisslén, L.; Schuster, B.-E.; Casu, M. B.; Chassé, T.; Heinemeyer, U.; Schreiber, F.

2011-01-01

Resonant and preresonant Raman spectra obtained on diindenoperylene (DIP) thin films are interpreted with calculations of the deformation of a relaxed excited molecule with density functional theory (DFT). The comparison of excited state geometries based on time-dependent DFT or on a constrained DFT scheme with observed absorption spectra of dissolved DIP reveals that the deformation pattern deduced from constrained DFT is more reliable. Most observed Raman peaks can be assigned to calculated A_g-symmetric breathing modes of DIP or their combinations. As the position of one of the laser lines used falls into a highly structured absorption band, we have carefully analyzed the Raman excitation profile arising from the frequency dependence of the dielectric tensor. This procedure gives Raman cross sections in good agreement with the observed relative intensities, both in the fully resonant and in the preresonant case.

Resonant Raman spectra of diindenoperylene thin films.

PubMed

Scholz, R; Gisslén, L; Schuster, B-E; Casu, M B; Chassé, T; Heinemeyer, U; Schreiber, F

2011-01-07

Resonant and preresonant Raman spectra obtained on diindenoperylene (DIP) thin films are interpreted with calculations of the deformation of a relaxed excited molecule with density functional theory (DFT). The comparison of excited state geometries based on time-dependent DFT or on a constrained DFT scheme with observed absorption spectra of dissolved DIP reveals that the deformation pattern deduced from constrained DFT is more reliable. Most observed Raman peaks can be assigned to calculated A(g)-symmetric breathing modes of DIP or their combinations. As the position of one of the laser lines used falls into a highly structured absorption band, we have carefully analyzed the Raman excitation profile arising from the frequency dependence of the dielectric tensor. This procedure gives Raman cross sections in good agreement with the observed relative intensities, both in the fully resonant and in the preresonant case.

Characterization of active phosphorus surface sites at synthetic carbonate-free fluorapatite using single-pulse 1H, 31P, and 31P CP MAS NMR.

PubMed

Jarlbring, Mathias; Sandström, Dan E; Antzutkin, Oleg N; Forsling, Willis

2006-05-09

The chemically active phosphorus surface sites defined as PO(x), PO(x)H, and PO(x)H2, where x = 1, 2, or 3, and the bulk phosphorus groups of PO4(3-) at synthetic carbonate-free fluorapatite (Ca5(PO4)3F) have been studied by means of single-pulse 1H,31P, and 31P CP MAS NMR. The changes in composition and relative amounts of each surface species are evaluated as a function of pH. By combining spectra from single-pulse 1H and 31P MAS NMR and data from 31P CP MAS NMR experiments at varying contact times in the range 0.2-3.0 ms, it has been possible to distinguish between resonance lines in the NMR spectra originating from active surface sites and bulk phosphorus groups and also to assign the peaks in the NMR spectra to the specific phosphorus species. In the 31P CP MAS NMR experiments, the spinning frequency was set to 4.2 kHz; in the single-pulse 1H MAS NMR experiments, the spinning frequency was 10 kHz. The 31P CP MAS NMR spectrum of fluorapatite at pH 5.9 showed one dominating resonance line at 2.9 ppm assigned to originate from PO4(3-) groups and two weaker shoulder peaks at 5.4 and 0.8 ppm which were assigned to the unprotonated PO(x) (PO, PO2-, and PO3(2-)) and protonated PO(x)H (PO2H and PO3H-) surface sites. At pH 12.7, the intensity of the peak representing unprotonated PO(x) surface sites has increased 1.7% relative to the bulk peak, while the intensity of the peaks of the protonated species PO(x)H have decreased 1.4% relative to the bulk peak. At pH 3.5, a resonance peak at -4.5 ppm has appeared in the 31P CP MAS NMR spectrum assigned to the surface species PO(x)H2 (PO3H2). The results from the 1H MAS and 31P CP MAS NMR measurements indicated that H+, OH-, and physisorbed H2O at the surface were released during the drying process at 200 degrees C.

1H, 15N, and 13C resonance assignments of the third domain from the S. aureus innate immune evasion protein Eap.

PubMed

Herrera, Alvaro I; Ploscariu, Nicoleta T; Geisbrecht, Brian V; Prakash, Om

2018-04-01

Staphylococcus aureus is a widespread and persistent pathogen of humans and livestock. The bacterium expresses a wide variety of virulence proteins, many of which serve to disrupt the host's innate immune system from recognizing and clearing bacteria with optimal efficiency. The extracellular adherence protein (Eap) is a multidomain protein that participates in various protein-protein interactions that inhibit the innate immune response, including both the complement system (Woehl et al in J Immunol 193:6161-6171, 2014) and Neutrophil Serine Proteases (NSPs) (Stapels et al in Proc Natl Acad Sci USA 111:13187-13192, 2014). The third domain of Eap, Eap3, is an ~ 11 kDa protein that was recently shown to bind complement component C4b (Woehl et al in Protein Sci 26:1595-1608, 2017) and therefore play an essential role in inhibiting the classical and lectin pathways of complement (Woehl et al in J Immunol 193:6161-6171, 2014). Since structural characterization of Eap3 is still incomplete, we acquired a series of 2D and 3D NMR spectra of Eap3 in solution. Here we report the backbone and side-chain 1 H, 15 N, and 13 C resonance assignments of Eap3 and its predicted secondary structure via the TALOS-N server. The assignment data have been deposited in the BMRB data bank under accession number 27087.

Analytic Solution of the Electromagnetic Eigenvalues Problem in a Cylindrical Resonator

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

Checchin, Mattia; Martinello, Martina

Resonant accelerating cavities are key components in modern particles accelerating facilities. These take advantage of electromagnetic fields resonating at microwave frequencies to accelerate charged particles. Particles gain finite energy at each passage through a cavity if in phase with the resonating field, reaching energies even of the order of $TeV$ when a cascade of accelerating resonators are present. In order to understand how a resonant accelerating cavity transfers energy to charged particles, it is important to determine how the electromagnetic modes are exited into such resonators. In this paper we present a complete analytical calculation of the resonating fields formore » a simple cylindrical-shaped cavity.« less

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

Pratt, S. T.; Chemistry

The photoelectron spectrum following resonant two-photon ionization of 1,4-diazabicyclo[2.2.2]octane (DABCO) was recorded with the laser tuned to the origin band of the S{sub 2}{l_arrow}S{sub 0} transition. The spectrum is consistent with the rapid radiationless transition from the S2 state into high vibrational levels of the S1 state, as proposed by Smith et al. Features in the double-resonance spectrum of Smith et al. that were previously assigned to photoionization of S(-) 3s(-){sup 1}A'{sub 2} vibrational levels populated by a radiationless transition from the S2 state are reinterpreted, with the conclusion that the S(-) state has yet to be observed.

Importance of lifetime effects in breakup and suppression of complete fusion in reactions of weakly bound nuclei

NASA Astrophysics Data System (ADS)

Cook, K. J.; Simpson, E. C.; Luong, D. H.; Kalkal, Sunil; Dasgupta, M.; Hinde, D. J.

2016-06-01

Background: Complete fusion cross sections in collisions of light weakly bound nuclei and high-Z targets show suppression of complete fusion at above-barrier energies. This has been interpreted as resulting from the breakup of the weakly bound nucleus prior to reaching the fusion barrier, reducing the probability of complete charge capture. Below-barrier studies of reactions of 9Be have found that the breakup of 8Be formed by neutron stripping dominates over direct breakup and that transfer-triggered breakup may account for the observed suppression of complete fusion. Purpose: This paper investigates how the above conclusions are affected by lifetimes of the resonant states that are populated prior to breakup. If the mean life of a populated resonance (above the breakup threshold) is much longer than the fusion time scale, then its breakup (decay) cannot suppress complete fusion. For short-lived resonances, the situation is more complex. This work explicitly includes the mean life of the short-lived 2+ resonance in 8Be in classical dynamical model calculations to determine its effect on energy and angular correlations of the breakup fragments and on model predictions of suppression of cross sections for complete fusion at above-barrier energies. Method: Previously performed coincidence measurements of breakup fragments produced in reactions of 9Be with 144Sm, 168Er, 186W, 196Pt, 208Pb, and 209Bi at energies below the barrier have been reanalyzed using an improved efficiency determination of the BALiN detector array. Predictions of breakup observables and of complete and incomplete fusion at energies above the fusion barrier are then made using the classical dynamical simulation code platypus, modified to include the effect of lifetimes of resonant states. Results: The agreement of the breakup observables is much improved when lifetime effects are included explicitly. Sensitivity to subzeptosecond lifetime is observed. The predicted suppression of complete fusion owing to breakup is nearly independent of Z and has an average value of ˜9 % . This is below the experimentally determined fusion suppression, which is typically ˜30 % in these systems. Conclusions: Inclusion of resonance lifetimes is essential to correctly reproduce breakup observables. This results in a larger fraction of nuclei remaining intact at the fusion-barrier radius compared with calculations that do not explicitly include lifetime effects. The more realistic treatment of breakup followed in this work leads to the conclusion that the suppression of complete fusion cannot be fully explained by breakup prior to reaching the fusion barrier. Only one-third of the observed fusion suppression can be attributed to the competing process of breakup. Other mechanisms that can suppress complete fusion must therefore be investigated. One of the possible candidates is cluster transfer that produces the same heavy targetlike nuclei as those formed by incomplete fusion.

F-100A on lakebed

NASA Technical Reports Server (NTRS)

1955-01-01

North American F-100A (52-5778) Super Sabre is parked on the Rogers Dry Lakebed at Edwards Air Force Base, California, 1955. This photo shows the large tail on the F-100A. When the basic research was completed on this F-100A another program was assigned. On March 5, 1957 two aeronautical engineers and a test pilot from NACA High-Speed Flight Station took the airplane to participate in a Gunnery Operations program at Nellis Air Force Base, Nevada. When the program was completed the aircraft returned for other assignments to NACA, at Edwards, California.

Identification of a new low energy 1u state in dicopper with resonant four-wave mixing.

PubMed

Visser, B; Beck, M; Bornhauser, P; Knopp, G; van Bokhoven, J A; Marquardt, R; Gourlaouen, C; Radi, P P

2017-12-07

The low energy electronic structure of the copper dimer has been re-investigated using non-linear four-wave mixing spectroscopy and high level ab initio calculations. In addition to the measurement of the previously reported A, B, and C electronic states, a new state denoted A' is identified with T 0 = 20 100.4090(16) cm -1 ( 63 Cu 2 ). Rotational analysis of the A'-X (0,0) and (1,0) transitions leads to the assignment of A' 1 u . Ab initio calculations present the first theoretical description of the low energy states of the copper dimer in Hund's case (c) and confirm the experimental assignment. The discovery of this new low energy excited state emphasizes that spin-orbit coupling is significant in states with d-hole electronic configurations and resolves a decades-long mystery in the initial assignment of the A state.

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

Pease, J.H.

The three dimensional structures of several small peptides were determined using a combination of {sup 1}H nuclear magnetic resonance (NMR) and distance geometry calculations. These techniques were found to be particularly helpful for analyzing structural differences between related peptides since all of the peptides' {sup 1}H NMR spectra are very similar. The structures of peptides from two separate classes are presented. Peptides in the first class are related to apamin, an 18 amino acid peptide toxin from honey bee venom. The {sup 1}H NMR assignments and secondary structure determination of apamin were done previously. Quantitative NMR measurements and distance geometrymore » calculations were done to calculate apamin's three dimensional structure. Peptides in the second class are 48 amino acid toxins from the sea anemone Radianthus paumotensis. The {sup 1}H NMR assignments of toxin II were done previously. The {sup 1}H NMR assignments of toxin III and the distance geometry calculations for both peptides are presented.« less

Towards unsupervised polyaromatic hydrocarbons structural assignment from SA-TIMS-FTMS data.

PubMed

Benigni, Paolo; Marin, Rebecca; Fernandez-Lima, Francisco

2015-10-01

With the advent of high resolution ion mobility analyzers and their coupling to ultrahigh resolution mass spectrometers, there is a need to further develop a theoretical workflow capable of correlating experimental accurate mass and mobility measurements with tridimensional candidate structures. In the present work, a general workflow is described for unsupervised tridimensional structural assignment based on accurate mass measurements, mobility measurements, in silico 2D-3D structure generation, and theoretical mobility calculations. In particular, the potential of this workflow will be shown for the analysis of polyaromatic hydrocarbons from Coal Tar SRM 1597a using selected accumulation - trapped ion mobility spectrometry (SA-TIMS) coupled to Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). The proposed workflow can be adapted to different IMS scenarios, can utilize different collisional cross-section calculators and has the potential to include MS n and IMS n measurements for faster and more accurate tridimensional structural assignment.

Opioid Antagonist Impedes Exposure.

ERIC Educational Resources Information Center

Merluzzi, Thomas V.; And Others

1991-01-01

Thirty spider-phobic adults underwent exposure to 17 phobic-related, graded performance tests. Fifteen subjects were assigned to naltrexone, an opioid antagonist, and 15 were assigned to placebo. Naltrexone had a significant effect on exposure, with naltrexone subjects taking significantly longer to complete first 10 steps of exposure and with…

Quantum transport in coupled resonators enclosed synthetic magnetic flux

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

Jin, L., E-mail: jinliang@nankai.edu.cn

Quantum transport properties are instrumental to understanding quantum coherent transport processes. Potential applications of quantum transport are widespread, in areas ranging from quantum information science to quantum engineering, and not restricted to quantum state transfer, control and manipulation. Here, we study light transport in a ring array of coupled resonators enclosed synthetic magnetic flux. The ring configuration, with an arbitrary number of resonators embedded, forms a two-arm Aharonov–Bohm interferometer. The influence of magnetic flux on light transport is investigated. Tuning the magnetic flux can lead to resonant transmission, while half-integer magnetic flux quantum leads to completely destructive interference and transmissionmore » zeros in an interferometer with two equal arms. -- Highlights: •The light transport is investigated through ring array of coupled resonators enclosed synthetic magnetic field. •Aharonov–Bohm ring interferometer of arbitrary configuration is investigated. •The half-integer magnetic flux quantum leads to destructive interference and transmission zeros for two-arm at equal length. •Complete transmission is available via tuning synthetic magnetic flux.« less

Iron overload in a teenager with xerocytosis: the importance of nuclear magnetic resonance imaging.

PubMed

Assis, Reijâne Alves de; Kassab, Carolina; Seguro, Fernanda Salles; Costa, Fernando Ferreira; Silveira, Paulo Augusto Achucarro; Wood, John; Hamerschlak, Nelson

2013-12-01

To report a case of iron overload secondary to xerocytosis, a rare disease in a teenager, diagnosed, by T2* magnetic resonance imaging. We report the case of a symptomatic patient with xerocytosis, a ferritin level of 350ng/mL and a significant cardiac iron overload. She was diagnosed by T2* magnetic resonance imaging and received chelation therapy Ektacytometric analysis confirmed the diagnosis of hereditary xerocytosis. Subsequent T2* magnetic resonance imaging demonstrated complete resolution of the iron overload in various organs, as a new echocardiography revealed a complete resolution of previous cardiac alterations. The patient remains in chelation therapy. Xerocytosis is a rare autosomal dominant genetic disorder characterized by dehydrated stomatocytosis. The patient may present with intense fatigue and iron overload. We suggest the regular use of T2* magnetic resonance imaging for the diagnosis and control of the response to iron chelation in xerocytosis, and we believe it can be used also in other hemolytic anemia requiring transfusions.

Rapid Protein Global Fold Determination Using Ultrasparse Sampling, High-Dynamic Range Artifact Suppression, and Time-Shared NOESY

PubMed Central

Coggins, Brian E.; Werner-Allen, Jonathan W.; Yan, Anthony; Zhou, Pei

2012-01-01

In structural studies of large proteins by NMR, global fold determination plays an increasingly important role in providing a first look at a target’s topology and reducing assignment ambiguity in NOESY spectra of fully-protonated samples. In this work, we demonstrate the use of ultrasparse sampling, a new data processing algorithm, and a 4-D time-shared NOESY experiment (1) to collect all NOEs in 2H/13C/15N-labeled protein samples with selectively-protonated amide and ILV methyl groups at high resolution in only four days, and (2) to calculate global folds from this data using fully automated resonance assignment. The new algorithm, SCRUB, incorporates the CLEAN method for iterative artifact removal, but applies an additional level of iteration, permitting real signals to be distinguished from noise and allowing nearly all artifacts generated by real signals to be eliminated. In simulations with 1.2% of the data required by Nyquist sampling, SCRUB achieves a dynamic range over 10000:1 (250× better artifact suppression than CLEAN) and completely quantitative reproduction of signal intensities, volumes, and lineshapes. Applied to 4-D time-shared NOESY data, SCRUB processing dramatically reduces aliasing noise from strong diagonal signals, enabling the identification of weak NOE crosspeaks with intensities 100× less than diagonal signals. Nearly all of the expected peaks for interproton distances under 5 Å were observed. The practical benefit of this method is demonstrated with structure calculations for 23 kDa and 29 kDa test proteins using the automated assignment protocol of CYANA, in which unassigned 4-D time-shared NOESY peak lists produce accurate and well-converged global fold ensembles, whereas 3-D peak lists either fail to converge or produce significantly less accurate folds. The approach presented here succeeds with an order of magnitude less sampling than required by alternative methods for processing sparse 4-D data. PMID:22946863

Identifying resonance frequency deviations for high order nano-wire ring resonator filters based on a coupling strength variation

NASA Astrophysics Data System (ADS)

Park, Sahnggi; Kim, Kap-Joong; Kim, Duk-Jun; Kim, Gyungock

2009-02-01

Third order ring resonators are designed and their resonance frequency deviations are analyzed experimentally by processing them with E-beam lithography and ICP etching in a CMOS nano-Fabrication laboratory. We developed a reliable method to identify and reduce experimentally the degree of deviation of each ring resonance frequency before completion of the fabrication process. The identified deviations can be minimized by the way to be presented in this paper. It is expected that this method will provide a significant clue to make a high order multi-channel ring resonators.

Nonlinear dynamics under varying temperature conditions of the resonating beams of a differential resonant accelerometer

NASA Astrophysics Data System (ADS)

Zhang, Jing; Wang, Yagang; Zega, Valentina; Su, Yan; Corigliano, Alberto

2018-07-01

In this work the nonlinear dynamic behaviour under varying temperature conditions of the resonating beams of a differential resonant accelerometer is studied from the theoretical, numerical and experimental points of view. A complete analytical model based on the Hamilton’s principle is proposed to describe the nonlinear behaviour of the resonators under varying temperature conditions and numerical solutions are presented in comparison with experimental data. This provides a novel perspective to examine the relationship between temperature and nonlinearity, which helps predicting the dynamic behaviour of resonant devices and can guide their optimal design.

Constructing cardiovascular fitness knowledge in physical education

PubMed Central

Zhang, Tan; Chen, Ang; Chen, Senlin; Hong, Deockki; Loflin, Jerry; Ennis, Catherine

2015-01-01

In physical education, it has become necessary for children to learn kinesiological knowledge for understanding the benefits of physical activity and developing a physically active lifestyle. This study was conducted to determine the extent to which cognitive assignments about healthful living and fitness contributed to knowledge growth on cardiorespiratory fitness and health. Fourth grade students (N = 616) from 15 randomly sampled urban elementary schools completed 34 cognitive assignments related to the cardiorespiratory physical activities they were engaged in across 10 lessons. Performance on the assignments were analyzed in relation to their knowledge gain measured using a standardized knowledge test. A multivariate discriminant analysis revealed that the cognitive assignments contributed to knowledge gain but the contribution varied assignment by assignment. A multiple regression analysis indicated that students’ assignment performance by lesson contributed positively to their knowledge growth scores. A content analysis based on the constructivist learning framework showed that observing–reasoning assignments contributed the most to knowledge growth. Analytical and analytical–application assignments contributed less than the constructivist theories would predict. PMID:25995702

Infrared resonance Raman, and excitation profile studies of Os/sub 2/(O/sub 2/CCH/sub 3/)/sub 4/Cl/sub 2/ and Os/sub 2/(O/sub 2/CCD/sub 3/)/sub 4/Cl/sub 2/. The assignment of the osmium-osmium stretching vibration for a complex involving an osmium-osmium multiple bond

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

Clark, R.J.H.; Hempleman, A.J.; Tocher, D.A.

1988-08-31

Extensive Raman studies (1525-40 cm/sup /minus/1/) of Os/sub 2/(O/sub 2/CCH/sub 3/)/sub 4/Cl/sub 2/ have led to the identification of the three strong bands, /nu//sub 1/, /nu//sub 2/, and /nu//sub 3/, at 229, 393, and 292 cm/sup /minus/1/ to the key skeletal stretching modes, /nu/(OsOs), /nu/(OsO), and /nu/(OsCl), respectively. Raman spectra of the complex at resonance with the intense electronic band at /lambda//sub max/ = 383 nm lead to the development of a six-membered overtone progression in /nu//sub 1/ as well as combination band progressions in /nu//sub 1/ based upon one quantum of either /nu//sub 2/ or /nu//sub 3/. This indicatesmore » that the principal structural change attendant upon excitation to the resonant state is along the OsOs coordinate. Fourier transform infrared spectra (3500-40 cm/sup /minus/1/) have also been obtained. Acetate deuteriation provides conclusive evidence for many of the infrared and Raman band assignments. The study provides the first firm identification of /nu/(OsOs) for a multiply bonded species.« less

Resonance Raman spectroscopy of 2H-labelled spheroidenes in petroleum ether and in the Rhodobacter sphaeroides reaction centre.

PubMed

Kok, P; Köhler, J; Groenen, E J; Gebhard, R; van der Hoef, I; Lugtenburg, J; Farhoosh, R; Frank, H A

1997-03-01

As a step towards the structural analysis of the carotenoid spheroidene in the Rhodobacter sphaeroides reaction centre, we present the resonance Raman spectra of 14-2H, 15-2H, 15'-2H, 14'-2H, 14,15'-2H2 and 15-15'-2H2 spheroidenes in petroleum ether and, except for 14,15'-2H2 spheroidene, in the Rb. sphaeroides R26 reaction center (RC). Analysis of the spectral changes upon isotopic substitution allows a qualitative assignment of most of the vibrational bands to be made. For the all-trans spheroidenes in solution the resonance enhancement of the Raman bands is determined by the participation of carbon carbon stretching modes in the centre of the conjugated chain, the C9 to C15' region. For the RC-bound 15,15'-cis spheroidenes, enhancement is determined by the participation of carbon-carbon stretching modes in the centre of the molecule, the C13 to C13' region. Comparison of the spectra in solution and in the RC reveals evidence for an out-of-plane distortion of the RC-bound spheroidene in the central C14 to C14' region of the carotenoid. The characteristic 1240 cm-1 band in the spectrum of the RC-bound spheroidene has been assigned to a normal mode that contains the coupled C12-C13 and C13'-C12' stretch vibrations.

Correlating MALDI and MRI Biomarkers of Breast Cancer

DTIC Science & Technology

2010-07-01

resonance imaging ( MRI ) with matrix-assisted laser desorption ionization (MALDI) analysis of healthy and tumorous ex vivo specimens in order to examine the...assess the correlation between physiological parameters reported by magnetic resonance (MR) imaging and tumor protein distribution determined from... imaging research (e.g., Cancer Imaging , Quantitative Magnetic Resonance Imaging , and Medical Image Registration classes) • completion of

Peak picking NMR spectral data using non-negative matrix factorization.

PubMed

Tikole, Suhas; Jaravine, Victor; Rogov, Vladimir; Dötsch, Volker; Güntert, Peter

2014-02-11

Simple peak-picking algorithms, such as those based on lineshape fitting, perform well when peaks are completely resolved in multidimensional NMR spectra, but often produce wrong intensities and frequencies for overlapping peak clusters. For example, NOESY-type spectra have considerable overlaps leading to significant peak-picking intensity errors, which can result in erroneous structural restraints. Precise frequencies are critical for unambiguous resonance assignments. To alleviate this problem, a more sophisticated peaks decomposition algorithm, based on non-negative matrix factorization (NMF), was developed. We produce peak shapes from Fourier-transformed NMR spectra. Apart from its main goal of deriving components from spectra and producing peak lists automatically, the NMF approach can also be applied if the positions of some peaks are known a priori, e.g. from consistently referenced spectral dimensions of other experiments. Application of the NMF algorithm to a three-dimensional peak list of the 23 kDa bi-domain section of the RcsD protein (RcsD-ABL-HPt, residues 688-890) as well as to synthetic HSQC data shows that peaks can be picked accurately also in spectral regions with strong overlap.

Nuclear magnetic resonance, vibrational spectroscopic studies, physico-chemical properties and computational calculations on (nitrophenyl) octahydroquinolindiones by DFT method.

PubMed

Pasha, M A; Siddekha, Aisha; Mishra, Soni; Azzam, Sadeq Hamood Saleh; Umapathy, S

2015-02-05

In the present study, 2'-nitrophenyloctahydroquinolinedione and its 3'-nitrophenyl isomer were synthesized and characterized by FT-IR, FT-Raman, (1)H NMR and (13)C NMR spectroscopy. The molecular geometry, vibrational frequencies, (1)H and (13)C NMR chemical shift values of the synthesized compounds in the ground state have been calculated by using the density functional theory (DFT) method with the 6-311++G (d,p) basis set and compared with the experimental data. The complete vibrational assignments of wave numbers were made on the basis of potential energy distribution using GAR2PED programme. Isotropic chemical shifts for (1)H and (13)C NMR were calculated using gauge-invariant atomic orbital (GIAO) method. The experimental vibrational frequencies, (1)H and (13)C NMR chemical shift values were found to be in good agreement with the theoretical values. On the basis of vibrational analysis, molecular electrostatic potential and the standard thermodynamic functions have been investigated. Copyright © 2014 Elsevier B.V. All rights reserved.

Imaging spectroscopy of the missing REMPI bands of methyl radicals: Final touches on all vibrational frequencies of the 3p Rydberg states

NASA Astrophysics Data System (ADS)

Pan, Huilin; Liu, Kopin

2018-01-01

(2 + 1) resonance-enhanced multiphoton ionization (REMPI) detection of methyl radicals, in particular that via the intermediate 3p Rydberg states, has shown to be a powerful method and thus enjoyed a wide range of applications. Methyl has six vibrational modes. Among them—including partially and fully deuterated isotopologs—four out of twenty vibrational frequencies in the intermediate 3p states have so far eluded direct spectroscopic determination. Here, by exploiting the imaging spectroscopy approach to a few judiciously selected chemical reactions, the four long-sought REMPI bands—CHD2(611), CH2D(311), CH2D(511), and CH2D(611)—are discovered, which complete the REMPI identification for probing any vibrational mode of excitation of methyl radical and its isotopologs. These results, in conjunction with those previously reported yet scattered in the literature, are summarized here for ready reference, which should provide all necessary information for further spectral assignments and future studies of chemical dynamics using this versatile REMPI scheme.

Optimized co-solute paramagnetic relaxation enhancement for the rapid NMR analysis of a highly fibrillogenic peptide.

PubMed

Oktaviani, Nur Alia; Risør, Michael W; Lee, Young-Ho; Megens, Rik P; de Jong, Djurre H; Otten, Renee; Scheek, Ruud M; Enghild, Jan J; Nielsen, Niels Chr; Ikegami, Takahisa; Mulder, Frans A A

2015-06-01

Co-solute paramagnetic relaxation enhancement (PRE) is an attractive way to speed up data acquisition in NMR spectroscopy by shortening the T 1 relaxation time of the nucleus of interest and thus the necessary recycle delay. Here, we present the rationale to utilize high-spin iron(III) as the optimal transition metal for this purpose and characterize the properties of its neutral chelate form Fe(DO3A) as a suitable PRE agent. Fe(DO3A) effectively reduces the T 1 values across the entire sequence of the intrinsically disordered protein α-synuclein with negligible impact on line width. The agent is better suited than currently used alternatives, shows no specific interaction with the polypeptide chain and, due to its high relaxivity, is effective at low concentrations and in 'proton-less' NMR experiments. By using Fe(DO3A) we were able to complete the backbone resonance assignment of a highly fibrillogenic peptide from α1-antitrypsin by acquiring the necessary suite of multidimensional NMR datasets in 3 h.

Rotational Spectroscopy and Conformational Studies of 4-PENTYNENITRILE, 4-PENTENENITRILE, and Glutaronitrile

NASA Astrophysics Data System (ADS)

Hays, Brian M.; Mehta-Hurt, Deepali; Jawad, Khadija M.; Hernandez-Castillo, Alicia O.; Abeysekera, Chamara; Zhang, Di; Zwier, Timothy S.

2017-06-01

The pure rotational spectra of 4-pentynenitrile, 4-pentenenitrile, and glutaronitrile were acquired using chirped pulse Fouirer transform microwave spectroscopy. 4-pentynenitrile and 4-pentenenitrile are the recombination products of two resonance stabilized radicals, propargyl + cyanomethyl or allyl + cyanomethyl, respectively, and are thus anticipated to be significant among the more complex nitriles in Titan's atmosphere. Indeed, these partially unsaturated alkyl cyanides have been found in laboratory analogs of tholins and are also expected to have interesting photochemistry. The optimized structures of all conformers below predicted energies of 500 \\wn were calculated for each molecule. Both of the conformers, trans and gauche, for 4-pentynenitrile have been identified and assigned. Five conformers were assigned in 4-pentenenitrile. The eclipsed conformers, with respect to the vinyl group, dominate the spectrum but some population was found in the syn conformers including the syn-gauche conformer, calculated to be 324 \\wn above the global minimum. The glutaronitrile spectrum contained only the two conformers below 500 \\wn, with reduced amount of the gauche trans conformer. The assigned spectra and structural assignments will be presented.

Vibrational normal modes of diazo-dimedone: A comparative study by Fourier infrared/Raman spectroscopies and conformational analysis by MM/QM

NASA Astrophysics Data System (ADS)

Téllez Soto, C. A.; Ramos, J. M.; Rianelli, R. S.; de Souza, M. C. B. V.; Ferreira, V. F.

2007-07-01

The 2-diazo-5,5-dimethyl-cyclohexane-1,3-dione ( 3) was synthesized and the FT-IR/Raman spectra were measured with the purpose of obtain a full assignment of the vibrational modes. Singular aspects concerning the -C dbnd N dbnd N oscillator are discussed in view of two strong bands observed in the region of 2300-2100 cm -1 in both, Infrared and Raman spectra. The density functional theory (DFT) was used to obtain the geometrical structure and for assisting in the vibrational assignment joint to the traditional normal coordinate analysis (NCA). The observed wavenumbers at 2145 (IR), 2144(R) are assigned as the coupled ν(N dbnd N) + ν(C dbnd N) vibrational mode with higher participation of the N dbnd N stretching. A 2188 cm -1 (IR) and at 2186 cm -1 (R) can be assigned as a overtone of one of ν(CC) normal mode or to a combination band of the fundamentals δ(CCH) found at 1169 cm -1 and the δ (CC dbnd N) found at 1017 cm -1 enhanced by Fermi resonance.

Reflection spectra of bio-organic materials in the 2.5-4 micron region and the interpretation of the infrared spectrum of Mars.

PubMed

Rea, D G; Belsky, T; Calvin, M

1964-01-01

The nature and assignment of the Martian spectral features observed by W. M. Sinton in the 3-4 micron region have been re-examined. It is shown that it is not possible to state unequivocally that there are absorption bands at 2710 (3.69 microns), 2790 (3.58 microns) and 2900 (3.45 microns) cm-1. Rather the possibility of the presence of true reflection features complicates the issue and enables only a wide range to be specified for the corresponding resonant frequencies. To clarify the assignment of these a large number of pure organic and inorganic solids, together with a selection of biological samples, have been recorded in reflection. The assignment of the features to organic matter, implying the presence of life on the Martian maria, is found to be improbable. While inorganic carbonates have bands in this region, they also do not provide a satisfactory explanation of the observations. The assignment of these Martian spectral features is then an open question.

28 CFR 345.35 - Assignments to FPI.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., color, religion, ethnic origin, age, or disability. (b) The SOI ordinarily makes assignments based on... course in pre-industrial training or on-the-job training (as available) before promotion to pay grade four. (2) An inmate who has not successfully completed pre-industrial or on-the-job training remains at...

Improving Preservice Elementary Teachers' Writing in a Science Context

ERIC Educational Resources Information Center

Everett, Susan; Luera, Gail; Otto, Charlotte

2008-01-01

The authors investigated whether a series of mini prewriting assignments linked to a formal paper describing an original research project would improve preservice elementary teachers' writing abilities in a science context. They compared 38 final reports from students who completed the prewriting assignments with 38 reports randomly selected from…

Men and Women in Ships: Preconceptions of the Crews.

ERIC Educational Resources Information Center

Greebler, Carol S.; And Others

Preintegration attitudes and expectations of 1,936 men and 346 women assigned to six Navy ships were measured before the women reported aboard, through the administration of gender-specific versions of the "Navy in Transition" questionnaire. An additional 483 men assigned to a ship not scheduled for integration completed the…

A Study of Science Teachers' Homework Practices

ERIC Educational Resources Information Center

Tas, Yasemin; Sungur-Vural, Semra; Öztekin, Ceren

2014-01-01

This study investigates Turkish middle school science teachers' homework practices, the value teachers attach to homework and teachers' communication with parents about homework. One hundred and sixty-eight teachers completed surveys. Teachers reported to assign homework frequently: 93.4 per cent of the teachers reported that they assign homework…

The Role of Parental Attitudes in Children's Motivation toward Homework Assignments

ERIC Educational Resources Information Center

Madjar, Nir; Shklar, Nitzan; Moshe, Limor

2016-01-01

Completing homework assignments is part of students' daily routine. Because this task is embedded within the home environment, parents play an important role in homework-related attitudes and behaviors. Recent findings have demonstrated that effort and cognitive engagement while doing homework are better proximal predictors of positive outcomes…

Effect of Sex Identification on Instrument Assignment by Band Directors

ERIC Educational Resources Information Center

Johnson, Christopher M.; Stewart, Erin E.

2004-01-01

The purpose of this study was to investigate the effect of sex identification on the assignment of instruments to beginning band students. Participants were band directors solicited at music conferences and music education students solicited from major universities across the United States. Participants completed an online survey about instrument…

47 CFR 1.1405 - File numbers.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 1 2012-10-01 2012-10-01 false File numbers. 1.1405 Section 1.1405... Attachment Complaint Procedures § 1.1405 File numbers. Each complaint which appears to be essentially complete under § 1.1404 will be accepted and assigned a file number. Such assignment is for administrative...

47 CFR 1.1405 - File numbers.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 1 2014-10-01 2014-10-01 false File numbers. 1.1405 Section 1.1405... Attachment Complaint Procedures § 1.1405 File numbers. Each complaint which appears to be essentially complete under § 1.1404 will be accepted and assigned a file number. Such assignment is for administrative...

47 CFR 1.1405 - File numbers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false File numbers. 1.1405 Section 1.1405... Procedures § 1.1405 File numbers. Each complaint which appears to be essentially complete under § 1.1404 will be accepted and assigned a file number. Such assignment is for administrative purposes only and does...

47 CFR 1.1405 - File numbers.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 1 2013-10-01 2013-10-01 false File numbers. 1.1405 Section 1.1405... Attachment Complaint Procedures § 1.1405 File numbers. Each complaint which appears to be essentially complete under § 1.1404 will be accepted and assigned a file number. Such assignment is for administrative...

47 CFR 1.1405 - File numbers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false File numbers. 1.1405 Section 1.1405... Procedures § 1.1405 File numbers. Each complaint which appears to be essentially complete under § 1.1404 will be accepted and assigned a file number. Such assignment is for administrative purposes only and does...

10 CFR 26.405 - Drug and alcohol testing.

Code of Federal Regulations, 2011 CFR

2011-01-01

...; and (4) Provide that an individual completing a test is immediately eligible for another random test... following conditions: (1) Pre-assignment. Before assignment to construct or direct the construction of... individual is engaging in substance abuse, as defined in § 26.5; (3) Post-accident. As soon as practical...

10 CFR 26.405 - Drug and alcohol testing.

Code of Federal Regulations, 2013 CFR

2013-01-01

...; and (4) Provide that an individual completing a test is immediately eligible for another random test... following conditions: (1) Pre-assignment. Before assignment to construct or direct the construction of... individual is engaging in substance abuse, as defined in § 26.5; (3) Post-accident. As soon as practical...

10 CFR 26.405 - Drug and alcohol testing.

Code of Federal Regulations, 2010 CFR

2010-01-01

...; and (4) Provide that an individual completing a test is immediately eligible for another random test... following conditions: (1) Pre-assignment. Before assignment to construct safety-or security-related SSCs; (2..., as defined in § 26.5; (3) Post-accident. As soon as practical after an event involving a human error...

10 CFR 26.405 - Drug and alcohol testing.

Code of Federal Regulations, 2014 CFR

2014-01-01

...; and (4) Provide that an individual completing a test is immediately eligible for another random test... following conditions: (1) Pre-assignment. Before assignment to construct or direct the construction of... individual is engaging in substance abuse, as defined in § 26.5; (3) Post-accident. As soon as practical...

10 CFR 26.405 - Drug and alcohol testing.

Code of Federal Regulations, 2012 CFR

2012-01-01

...; and (4) Provide that an individual completing a test is immediately eligible for another random test... following conditions: (1) Pre-assignment. Before assignment to construct or direct the construction of... individual is engaging in substance abuse, as defined in § 26.5; (3) Post-accident. As soon as practical...

40 CFR 86.1826-01 - Assigned deterioration factors for small-volume manufacturers and small-volume test groups.

Code of Federal Regulations, 2014 CFR

2014-07-01

... applying deterioration factors. Manufacturers may use assigned deterioration factors that the Administrator determines and prescribes. (1) The deterioration factors will be the Administrator's estimate, periodically... using the industry-wide database of previously completed durability data vehicles or engines used for...

The effects of bedtime writing on difficulty falling asleep: A polysomnographic study comparing to-do lists and completed activity lists.

PubMed

Scullin, Michael K; Krueger, Madison L; Ballard, Hannah K; Pruett, Natalya; Bliwise, Donald L

2018-01-01

Bedtime worry, including worrying about incomplete future tasks, is a significant contributor to difficulty falling asleep. Previous research showed that writing about one's worries can help individuals fall asleep. We investigated whether the temporal focus of bedtime writing-writing a to-do list versus journaling about completed activities-affected sleep onset latency. Fifty-seven healthy young adults (18-30) completed a writing assignment for 5 min prior to overnight polysomnography recording in a controlled sleep laboratory. They were randomly assigned to write about tasks that they needed to remember to complete the next few days (to-do list) or about tasks they had completed the previous few days (completed list). Participants in the to-do list condition fell asleep significantly faster than those in the completed-list condition. The more specifically participants wrote their to-do list, the faster they subsequently fell asleep, whereas the opposite trend was observed when participants wrote about completed activities. Therefore, to facilitate falling asleep, individuals may derive benefit from writing a very specific to-do list for 5 min at bedtime rather than journaling about completed activities. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Online video bridges gap between orientation and first session for arts in medicine volunteers.

PubMed

Gregory, Dianne

2009-01-01

An online video assignment was developed to facilitate transition from the orientation session to the first contact with hospital patients for music therapy majors and other students enrolled in an Arts in Medicine service learning course (AIMS). All students (N = 84) completed a 2 hour hospital orientation session. After the orientation session the experimental group (n = 42) completed an online video assignment before volunteering at the hospital The control group (n = 42) began volunteering after the orientation session without completing the video assignment. Analysis indicates the majority of both groups initiated their first session independently without assistance from other AIMS volunteers, an experienced AIM volunteer, an AIM assistant, or hospital staff member. The majority of both groups also engaged at least one patient during their first visit at the hospital. Content analysis of "first contact" weekly reports, however, indicated experimental group students wrote longer reports and included more positive comments, particularly about patients, compared to control group students. Volunteers in the experimental group also began their contacts as scheduled on the course calendar compared to later starting dates of control group volunteers.

Nanoscale devices based on plasmonic coaxial waveguide resonators

NASA Astrophysics Data System (ADS)

Mahigir, A.; Dastmalchi, P.; Shin, W.; Fan, S.; Veronis, G.

2015-02-01

Waveguide-resonator systems are particularly useful for the development of several integrated photonic devices, such as tunable filters, optical switches, channel drop filters, reflectors, and impedance matching elements. In this paper, we introduce nanoscale devices based on plasmonic coaxial waveguide resonators. In particular, we investigate threedimensional nanostructures consisting of plasmonic coaxial stub resonators side-coupled to a plasmonic coaxial waveguide. We use coaxial waveguides with square cross sections, which can be fabricated using lithography-based techniques. The waveguides are placed on top of a silicon substrate, and the space between inner and outer coaxial metals is filled with silica. We use silver as the metal. We investigate structures consisting of a single plasmonic coaxial resonator, which is terminated either in a short or an open circuit, side-coupled to a coaxial waveguide. We show that the incident waveguide mode is almost completely reflected on resonance, while far from the resonance the waveguide mode is almost completely transmitted. We also show that the properties of the waveguide systems can be accurately described using a single-mode scattering matrix theory. The transmission and reflection coefficients at waveguide junctions are either calculated using the concept of the characteristic impedance or are directly numerically extracted using full-wave three-dimensional finite-difference frequency-domain simulations.

Interference effect as resonance killer of newly observed charmoniumlike states Y(4320) and Y(4390)

NASA Astrophysics Data System (ADS)

Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

2018-02-01

In this letter, we decode the newly observed charmoniumlike states, Y(4320) and Y(4390), by introducing interference effect between ψ (4160) and ψ (4415), which plays a role of resonance killer for Y(4320) and Y(4390). It means that two newly reported charmoniumlike states are not genuine resonances, according to which we can naturally explain why two well-established charmonia ψ (4160) and ψ (4415) are missing in the cross sections of e^+e^- → π ^+ π ^- J/ψ and π ^+ π ^- h_c simultaneously. To well describe the detailed data of these cross sections around √{s}=4.2 GeV, our study further illustrates that a charmoniumlike structure Y(4220) must be introduced. As a charmonium, Y(4220) should dominantly decay into its open-charm channel e^+e^- → D^0 π ^+ D^{*-}, which provides an extra support to ψ (4S) assignment to Y(4220). In fact, this interference effect introduced to explain Y(4320) and Y(4390) gives a typical example of non-resonant explanations to the observed XYZ states, which should be paid more attention especially before identifying the observed XYZ states as genuine resonances.

Distribution functions for orbits trapped at the resonances in the Galactic disc

NASA Astrophysics Data System (ADS)

Monari, G.

2017-12-01

The present-day response of a Galactic disc stellar population to a non-axisymmetric perturbation of the potential has previously been computed through perturbation theory within the phase-space coordinates of the unperturbed axisymmetric system. Such an Eulerian linearized treatment however leads to singularities at resonances, which prevent quantitative comparisons with data. Monari et al. manage to capture the behaviour of the distribution function (DF) at a resonance in a Lagrangian approach, by averaging the Hamiltonian over fast angle variables and re-expressing the DF in terms of a new set of canonical actions and angles variables valid in the resonant region. They then follow the prescription of Binney (2016), assigning to the resonant DF the time average along the orbits of the axisymmetric DF expressed in the new set of actions and angles. This boils down to phase-mixing the DF in terms of the new angles, such that the DF for trapped orbits only depends on the new set of actions. This opens the way to quantitatively fitting the effects of the bar and spirals to Gaia data in terms of distribution functions in action space.

Application of the Extended Completeness Relation to the Absorbing Boundary Condition

NASA Astrophysics Data System (ADS)

Iwasaki, Masataka; Otani, Reiji; Ito, Makoto

The strength function of the linear response by the external field is calculated in the formalism of the absorbing boundary condition (ABC). The dipole excitation of a schematic two-body system is treated in the present study. The extended completeness relation, which is assumed on the analogy of the formulation in the complex scaling method (CSM), is applied to the calculation of the strength function. The calculation of the strength function is successful in the present formalism and hence, the extended completeness relation seems to work well in the ABC formalism. The contributions from the resonance and the non-resonant continuum are also analyzed according to the decomposition of the energy levels in the extended completeness relation.

Exploiting Quantum Resonance to Solve Combinatorial Problems

NASA Technical Reports Server (NTRS)

Zak, Michail; Fijany, Amir

2006-01-01

Quantum resonance would be exploited in a proposed quantum-computing approach to the solution of combinatorial optimization problems. In quantum computing in general, one takes advantage of the fact that an algorithm cannot be decoupled from the physical effects available to implement it. Prior approaches to quantum computing have involved exploitation of only a subset of known quantum physical effects, notably including parallelism and entanglement, but not including resonance. In the proposed approach, one would utilize the combinatorial properties of tensor-product decomposability of unitary evolution of many-particle quantum systems for physically simulating solutions to NP-complete problems (a class of problems that are intractable with respect to classical methods of computation). In this approach, reinforcement and selection of a desired solution would be executed by means of quantum resonance. Classes of NP-complete problems that are important in practice and could be solved by the proposed approach include planning, scheduling, search, and optimal design.

Total angular momenta of high-lying odd levels of U I at ∼ 4 eV using resonance ionization laser polarization spectroscopy

NASA Astrophysics Data System (ADS)

Rath, Asawari D.; Kundu, S.; Ray, A. K.

2018-02-01

Laser induced photoionization of atoms shows significant dependence on the choice of polarizations of lasers. In multi-step, multi-photon excitation and subsequent ionization of atoms different polarization combinations of the exciting lasers lead to distinctly different ion yields. This fact is exploited in this work to determine total angular momenta of odd-parity energy levels of U I lying at ∼ 4 eV from its ground level using resonance ionization laser polarization spectroscopy in time of flight mass spectrometer. These levels are populated by two-step resonant excitation using two pulsed dye lasers with preset polarizations of choice followed by nonresonant ionization by third laser. The dependence of ionization yield on specific polarizations of the first two lasers is studied experimentally for each level under consideration. This dependence when compared to simulations makes possible unambiguous assignment of J angular momenta to these levels.

Nuclear Resonance Vibrational Spectra of Five-Coordinate Imidazole-ligated Iron(II) Porphyrinates

PubMed Central

Hu, Chuanjiang; Barabanschikov, Alexander; Ellison, Mary K.; Zhao, Jiyong; Alp, E. Ercan; Sturhahn, Wolfgang; Zgierski, Marek Z.; Sage, J. Timothy; Scheidt, W. Robert

2012-01-01

Nuclear resonance vibrational spectra have been obtained for six five-coordinate imidazole-ligated iron(II) porphyrinates, [Fe(Por)(L)] (Por = tetraphenylporphyrinate, octaethylporphyrinate, tetratolylporphyrinate or protoporphyrinate IX and L = 2-methylimidazole or 1,2-dimethylimidazole). Measurements have been made on both powder and oriented crystal samples. The spectra are dominated by strong signals around 200–300 cm−1. Although the in-plane and out-of-plane vibrations are seriously overlapped, oriented crystal spectra allow their deconvolution. Thus, oriented crystal experimental data, along with DFT calculations, enable the assignment of key vibrations in the spectra. Molecular dynamics are also discussed. The nature of the Fe–NIm vibrations has been elaborated further than was possible from resonance Raman studies. Our study suggests that the Fe motions are coupled with the porphyrin core and peripheral groups motions. Both peripheral groups and their conformations have significant influence on the vibrational spectra (position and shape). PMID:22243131

Evaluation of resonances above the proton threshold in 26Si

NASA Astrophysics Data System (ADS)

Chipps, K. A.

2016-09-01

26Al remains an intriguing target for observational gamma-ray astronomy, thanks to its characteristic decay. The 25Al(p, γ)26Si reaction is the crucial link in a sequence that bypasses the production of the observable 26Alg . s . in favor of the isomeric state, and as such has been the focus of many studies. Considerable confusion in this regard has arisen from the use of outdated excitation energies and masses in reaction studies and rate evaluations. Recalibration of existing data from the literature has resulted in updated excitation and resonance energies, but open questions remain, particularly with regard to spin assignments and partial widths/resonance strengths. A discussion of the levels just above the proton threshold in 26Si relevant to the astrophysical 25Al(p, γ)26Si reaction rate will be presented. This work is funded by the US Department of Energy, Office of Science, Office of Nuclear Physics.

Triple Resonance Solid State NMR Experiments with Reduced Dimensionality Evolution Periods

NASA Astrophysics Data System (ADS)

Astrof, Nathan S.; Lyon, Charles E.; Griffin, Robert G.

2001-10-01

Two solid state NMR triple resonance experiments which utilize the simultaneous incrementation of two chemical shift evolution periods to obtain a spectrum with reduced dimensionality are described. The CON CA experiment establishes the correlation of 13Ci-1 to 13Cαi and 15Ni by simultaneously encoding the 13COi-1 and 15Ni chemical shifts. The CAN COCA experiment establishes the correlation 13Cai and 15COi to 13Cαi-1 and 15Ni-1 within a single experiment by simultaneous encoding of the 13Cαi and 15Ni chemical shifts. This experiment establishes sequential amino acid correlations in close analogy to the solution state HNCA experiment. Reduced dimensionality 2D experiments are a practical alternative to recording multiple 3D data sets for the purpose of obtaining sequence-specific resonance assignments of peptides and proteins in the solid state.

High-Resolution Triple Resonance Autoionization of Uranium Isotopes

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

Schumann, Philipp G.; Wendt, K; Bushaw, Bruce A.

2005-11-01

The near-threshold autoionization (AI) spectrum of uranium has been investigated by triple-resonance excitation with single-mode continuous lasers. Spectra were recorded over the first {approx}30 cm-1 above the first ionization limit at a resolution of 3x10-4 cm 1 using intermediate states with different J values (6, 7, 8) to assign AI level total angular momentum JAI = 5 to 9. Resonances with widths ranging from 8 MHz to 30 GHz were observed; the strongest ones have JAI = 9 and widths of {approx} 60 MHz. Hyperfine structures for 235U and isotope shifts for 234,235U have been measured in the two intermediatemore » levels and in the final AI level for the most favorable excitation path. These measurements were performed using aqueous samples containing sub-milligram quantities of uranium at natural isotopic abundances, indicating the potential of this approach for trace isotope ratio determinations.« less

Clinical and Morphological Changes Following 2 Rehabilitation Programs for Acute Hamstring Strain Injuries: A Randomized Clinical Trial

PubMed Central

SILDER, AMY; SHERRY, MARC A.; SANFILIPPO, JENNIFER; TUITE, MICHAEL J.; HETZEL, SCOTT J.; HEIDERSCHEIT, BRYAN C.

2013-01-01

STUDY DESIGN Randomized, double-blind, parallel-group clinical trial. OBJECTIVES To assess differences between a progressive agility and trunk stabilization rehabilitation program and a progressive running and eccentric strengthening rehabilitation program in recovery characteristics following an acute hamstring injury, as measured via physical examination and magnetic resonance imaging (MRI). BACKGROUND Determining the type of rehabilitation program that most effectively promotes muscle and functional recovery is essential to minimize reinjury risk and to optimize athlete performance. METHODS Individuals who sustained a recent hamstring strain injury were randomly assigned to 1 of 2 rehabilitation programs: (1) progressive agility and trunk stabilization or (2) progressive running and eccentric strengthening. MRI and physical examinations were conducted before and after completion of rehabilitation. RESULTS Thirty-one subjects were enrolled, 29 began rehabilitation, and 25 completed rehabilitation. There were few differences in clinical or morphological outcome measures between rehabilitation groups across time, and reinjury rates were low for both rehabilitation groups after return to sport (4 of 29 subjects had reinjuries). Greater craniocaudal length of injury, as measured on MRI before the start of rehabilitation, was positively correlated with longer return-to-sport time. At the time of return to sport, although all subjects showed a near-complete resolution of pain and return of muscle strength, no subject showed complete resolution of injury as assessed on MRI. CONCLUSION The 2 rehabilitation programs employed in this study yielded similar results with respect to hamstring muscle recovery and function at the time of return to sport. Evidence of continuing muscular healing is present after completion of rehabilitation, despite the appearance of normal physical strength and function on clinical examination. LEVEL OF EVIDENCE Therapy, level 1b–. J Orthop Sports Phys Ther 2013;43(5):284-299. Epub 13 March 2013. doi:10.2519/jospt.2013.4452 PMID:23485730

Meta-cognitive student reflections

NASA Astrophysics Data System (ADS)

Barquist, Britt; Stewart, Jim

2009-05-01

We have recently concluded a project testing the effectiveness of a weekly assignment designed to encourage awareness and improvement of meta-cognitive skills. The project is based on the idea that successful problem solvers implement a meta-cognitive process in which they identify the specific concept they are struggling with, and then identify what they understand, what they don't understand, and what they need to know in order to resolve their problem. The assignment required the students to write an email assessing the level of completion of a weekly workbook assignment and to examine in detail their experiences regarding a specific topic they struggled with. The assignment guidelines were designed to coach them through this meta-cognitive process. We responded to most emails with advice for next week's assignment. Our data follow 12 students through a quarter consisting of 11 email assignments which were scored using a rubric based on the assignment guidelines. We found no correlation between rubric scores and final grades. We do have anecdotal evidence that the assignment was beneficial.

Temperature Dependence of NMR Relaxation Times of Nucleoside Triphosphates and Inorganic Phosphate in the Isolated Perfused Rat Liver. Effect on Pi Compartmentation

NASA Astrophysics Data System (ADS)

Dufour, Sylvie; Thiaudière, Eric; Vidal, Giovanni; Gallis, Jean-Louis; Rousse, Nicole; Canioni, Paul

1996-11-01

The effect of temperature on31P NMR spectra from isolated perfused rat livers was studied at 9.4 T. Relaxation times (T1andT2) of nucleoside triphosphates (NTP) and inorganic phosphate (Pi) were determined at 37, 25, 15, and 4°C. Under hypothermic conditions, an unexpected apparent line sharpening in the Pi spectral region and a clear emergence of an additional Pi resonance were observed. This additional signal was assigned to mitochondrial Pi.T1values obtained for cytosolic and mitochondrial Pi at 4°C were 1.14 ± 0.24 s (n= 5) and 0.71 ± 0.18 s (n= 5), respectively. No significant mitochondrial contribution to the Pi resonance was observed at 37°C. Quantification of Pi and NTP liver contents at 37 and 4°C was performed by comparing the perfused liver spectrum and the corresponding perchloric acid extract spectrum. Under experimental conditions of low external Pi (0.12 mM), it was concluded that intracellular Pi was completely NMR-visible at 4 and 37°C. The observation of the mitochondrial Pi signal at 4°C was well explained by an increase in the Pi level within the matrix, in response to the mitochondrial swelling induced by hypothermia, as observed by electron microscopy.T2values for the cytosolic Pi at 37 and 4°C were 17 ± 4 ms (n= 8) and 22 ± 4 ms (n= 10), respectively. Comparison with measured linewidths indicated that line broadening for the main phosphorylated metabolites-including matrix Pi-was the result ofB0field inhomogeneity. The additional broadening of the cytosolic Pi resonance at 4 and 37°C was attributed to pH heterogeneity within the liver.

Compton scattering from the proton in an effective field theory with explicit Delta degrees of freedom

NASA Astrophysics Data System (ADS)

McGovern, J. A.; Phillips, D. R.; Grießhammer, H. W.

2013-01-01

We analyse the proton Compton-scattering differential cross section for photon energies up to 325 MeV using Chiral Effective Field Theory (χEFT) and extract new values for the electric and magnetic polarisabilities of the proton. Our approach builds in the key physics in two different regimes: photon energies ω ≲ m π ("low energy"), and the higher energies where the Δ(1232) resonance plays a key role. The Compton amplitude is complete at N4LO, {O}( {e^2 δ ^4 } ), in the low-energy region, and at NLO, {O}( {e^2 δ ^0 } ), in the resonance region. Throughout, the Delta-pole graphs are dressed with π N loops and γN Δ vertex corrections. A statistically consistent database of proton Compton experiments is used to constrain the free parameters in our amplitude: the M1 γN Δ transition strength b 1 (which is fixed in the resonance region) and the polarisabilities α E1 and β M1 (which are fixed from data below 170 MeV). In order to obtain a reasonable fit, we find it necessary to add the spin polarisability γ M1 M1 as a free parameter, even though it is, strictly speaking, predicted in χEFT at the order to which we work. We show that the fit is consistent with the Baldin sum rule, and then use that sum rule to constrain α E1 + β M1. In this way we obtain α E1 = [10.65 ± 0.35(stat) ± 0.2(Baldin) ± 0.3(theory)] × 10-4 fm3 and β M1 = [3.15 ∓ 0.35(state) ± 0.2(Baldin) ∓ 0.3()theory] × 10-4 fm3, with χ2 = 113.2 for 135 degrees of freedom. A detailed rationale for the theoretical uncertainties assigned to this result is provided.

BATMAN--an R package for the automated quantification of metabolites from nuclear magnetic resonance spectra using a Bayesian model.

PubMed

Hao, Jie; Astle, William; De Iorio, Maria; Ebbels, Timothy M D

2012-08-01

Nuclear Magnetic Resonance (NMR) spectra are widely used in metabolomics to obtain metabolite profiles in complex biological mixtures. Common methods used to assign and estimate concentrations of metabolites involve either an expert manual peak fitting or extra pre-processing steps, such as peak alignment and binning. Peak fitting is very time consuming and is subject to human error. Conversely, alignment and binning can introduce artefacts and limit immediate biological interpretation of models. We present the Bayesian automated metabolite analyser for NMR spectra (BATMAN), an R package that deconvolutes peaks from one-dimensional NMR spectra, automatically assigns them to specific metabolites from a target list and obtains concentration estimates. The Bayesian model incorporates information on characteristic peak patterns of metabolites and is able to account for shifts in the position of peaks commonly seen in NMR spectra of biological samples. It applies a Markov chain Monte Carlo algorithm to sample from a joint posterior distribution of the model parameters and obtains concentration estimates with reduced error compared with conventional numerical integration and comparable to manual deconvolution by experienced spectroscopists. http://www1.imperial.ac.uk/medicine/people/t.ebbels/ t.ebbels@imperial.ac.uk.

Backbone resonance assignment of an insect arylalkylamine N-acetyltransferase from Bombyx mori reveals conformational heterogeneity.

PubMed

Aboalroub, Adam A; Zhang, Ziming; Keramisanou, Dimitra; Gelis, Ioannis

2017-04-01

Arylalkylamine N-acetyltransferases (AANATs) catalyze the transfer of an acetyl group from the acetyl-group donor, acetyl-CoA, to an arylalkylamine acceptor. Although a single AANAT has been identified in mammals, insects utilize multiple AANATs in a diverse array of biological processes. AANATs belong to the GCN5-related acetyltransferase (GNAT) superfamily of enzymes, which despite their overall very low sequence homology, are characterized by a well conserved catalytic core domain. The structural properties of many GNATs have been extensively studied by X-ray crystallography that revealed common features during the catalytic cycle. Here we report the 1 H, 13 C and 15 N backbone NMR resonance assignment of the 24 kDa AANAT3 from Bombyx mori (bmAANAT3) as a first step towards understanding the role of protein dynamics in the catalytic properties of AANATs. Our preliminary solution NMR studies reveal that bmAANAT3 is well-folded in solution. The P-loop, which is responsible for cofactor binding, is flexible in the free-state, while a large region of the enzyme interconverts between two distinct conformations in the slow exchange regime.

Fragment-Based Electronic Structure Approach for Computing Nuclear Magnetic Resonance Chemical Shifts in Molecular Crystals.

PubMed

Hartman, Joshua D; Beran, Gregory J O

2014-11-11

First-principles chemical shielding tensor predictions play a critical role in studying molecular crystal structures using nuclear magnetic resonance. Fragment-based electronic structure methods have dramatically improved the ability to model molecular crystal structures and energetics using high-level electronic structure methods. Here, a many-body expansion fragment approach is applied to the calculation of chemical shielding tensors in molecular crystals. First, the impact of truncating the many-body expansion at different orders and the role of electrostatic embedding are examined on a series of molecular clusters extracted from molecular crystals. Second, the ability of these techniques to assign three polymorphic forms of the drug sulfanilamide to the corresponding experimental (13)C spectra is assessed. This challenging example requires discriminating among spectra whose (13)C chemical shifts differ by only a few parts per million (ppm) across the different polymorphs. Fragment-based PBE0/6-311+G(2d,p) level chemical shielding predictions correctly assign these three polymorphs and reproduce the sulfanilamide experimental (13)C chemical shifts with 1 ppm accuracy. The results demonstrate that fragment approaches are competitive with the widely used gauge-invariant projector augmented wave (GIPAW) periodic density functional theory calculations.

1H, 13C, and 15N backbone and side chain resonance assignments of thermophilic Geobacillus kaustophilus cyclophilin-A

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

Holliday, Michael; Zhang, Fengli; Isern, Nancy G.

2014-04-01

Cyclophilins catalyze the reversible peptidyl-prolyl isomerization of their substrates and are present across all kingdoms of life from humans to bacteria. Although numerous biological roles have now been discovered for cyclophilins, their function was initially ascribed to their chaperone-like activity in protein folding where they catalyze the often rate-limiting step of proline isomerization. This chaperone-like activity may be especially important under extreme conditions where cyclophilins are often over expressed, such as in tumors for human cyclophilins {Lee, 2010 #1167}, but also in organisms that thrive under extreme conditions, such as theromophilic bacteria. Moreover, the reversible nature of the peptidyl-prolyl isomerizationmore » reaction catalyzed by cyclophilins has allowed these enzymes to serve as model systems for probing the role of conformational changes during catalytic turnover {Eisenmesser, 2002 #20;Eisenmesser, 2005 #203}. Thus, we present here the resonance assignments of a thermophilic cyclophilin from Geobacillus kaustophilus derived from deep-sea sediment {Takami, 2004 #1384}. This thermophilic cyclophilin may now be studied at a variety of temperatures to provide insight into the comparative structure, dynamics, and catalytic mechanism of cyclophilins.« less

Understanding API-polymer proximities in amorphous stabilized composite drug products using fluorine-carbon 2D HETCOR solid-state NMR.

PubMed

Abraham, Anuji; Crull, George

2014-10-06

A simple and robust method for obtaining fluorine-carbon proximities was established using a (19)F-(13)C heteronuclear correlation (HETCOR) two-dimensional (2D) solid-state nuclear magnetic resonance (ssNMR) experiment under magic-angle spinning (MAS). The method was applied to study a crystalline active pharmaceutical ingredient (API), avagacestat, containing two types of fluorine atoms and its API-polymer composite drug product. These results provide insight into the molecular structure, aid with assigning the carbon resonances, and probe API-polymer proximities in amorphous spray dried dispersions (SDD). This method has an advantage over the commonly used (1)H-(13)C HETCOR because of the large chemical shift dispersion in the fluorine dimension. In the present study, fluorine-carbon distances up to 8 Å were probed, giving insight into the API structure, crystal packing, and assignments. Most importantly, the study demonstrates a method for probing an intimate molecular level contact between an amorphous API and a polymer in an SDD, giving insights into molecular association and understanding of the role of the polymer in API stability (such as recrystallization, degradation, etc.) in such novel composite drug products.

STS-107 Crew Surgeon

NASA Technical Reports Server (NTRS)

Johnston, Smith

2005-01-01

NASA Crew Surgeons (CS) provides medical support to crewmembers assigned to a space flight. Upon this mission assignment, CS s develop close working and personal relationships with crewmembers, their families and close friends. This discussion covers the role of the NASA CS from start of a mission assignment through its completion. Specific emphasis is placed on events associated with the Columbia accident to include; premission planning, initial family medical support, interface with the astronaut Casualty Assistance Control Officers (CACOs), AFIP relationship and on-going care for the families.

An Active-Learning Approach to Fostering Understanding of Research Methods in Large Classes

ERIC Educational Resources Information Center

LaCosse, Jennifer; Ainsworth, Sarah E.; Shepherd, Melissa A.; Ent, Michael; Klein, Kelly M.; Holland-Carter, Lauren A.; Moss, Justin H.; Licht, Mark; Licht, Barbara

2017-01-01

The current investigation tested the effectiveness of an online student research project designed to supplement traditional methods (e.g., lectures, discussions, and assigned readings) of teaching research methods in a large-enrollment Introduction to Psychology course. Over the course of the semester, students completed seven assignments, each…

Helping Your Students with Homework: A Guide for Teachers.

ERIC Educational Resources Information Center

Paulu, Nancy; Darby, Linda B., Ed.

This guide for elementary and secondary teachers discusses 18 tips for creating meaningful homework assignments that students will complete. Following introductory sections that explore hurdles to homework, the guide details the following tips: (1) lay out expectations early in the school year; (2) create assignments with a purpose; (3) make sure…

Sortings, Cutaways, and Bindings: Quilt-Making as Arts-Based Practice for Social Justice Teaching

ERIC Educational Resources Information Center

Kuthy, Diane; Broadwater, Kay

2014-01-01

This article describes a studio assignment grounded in social learning theory and intersectionality completed by preservice teachers during their first art education class, enabling students to begin to develop nuanced understandings about categories of difference. A studio assignment combines experiences in museum, community, and school settings…

Emotional Disclosure through Writing or Speaking Modulates Latent Epstein-Barr Virus Antibody Titers.

ERIC Educational Resources Information Center

Esterling, Brian A.; And Others

1994-01-01

Healthy Epstein-Barr virus (EBV) seropositive undergraduates (n=57) completed personality inventory, provided blood samples, and were randomly assigned to write/talk about stressful events, or to write about trivial events. Those assigned to verbal/stressful condition had significantly lower EBV antibody titers (suggesting better cellular immune…

Applying Social Psychological Concepts Outside the Classroom

ERIC Educational Resources Information Center

Lakin, Jessica L.; Wichman, Aaron L.

2005-01-01

This article evaluates a writing assignment in which social psychology students gathered examples from outside the classroom (e.g., cartoons, movies) and analyzed them with course material. Compared to a control group, students who completed the assignment learned that it was easier to apply social psychology to the real world. A follow-up survey…

Assigning a Thesis Project In the Two-Year Architectural Technology Program

ERIC Educational Resources Information Center

Obermeyer, Thomas

1977-01-01

The "thesis project" assigned in the sixth quarter of the eight-quarter architectural technology program at the Dakota County Area Vocational-Technical Institute in Rosemont, Minnesota, requires the students to design a building for a local public service organization or government agency. The complete project will include a program, a…

Using Pinterest in Undergraduate Social Work Education: Assignment Development and Pilot Survey Results

ERIC Educational Resources Information Center

Baker, Lisa R.; Hitchcock, Laurel Iverson

2017-01-01

This article describes the development, implementation, and assessment of a social media assignment using Pinterest as a tool for student engagement and professional development in two undergraduate social work courses. Twenty-one undergraduate students enrolled in Human Behavior and the Social Environment (HBSE) courses completed the assignment…

Accountability Groups to Enhance Language Learning in a University Intensive English Program

ERIC Educational Resources Information Center

Lippincott, Dianna

2017-01-01

This mixed methods classroom research examined if accountability groups in the lower proficiency levels of a university intensive English program would improve students' language acquisition. Students were assigned partners for the study period with whom they completed assignments inside and outside of class, as well as set goals for use of…

Learning by Identification of Mistakes in Workings in Engineering Modules

ERIC Educational Resources Information Center

Chian, S. C.

2018-01-01

Conventional graded assignments are commonly structured in a format where students attempt a prescribed question and are graded based on the completeness of their workings rather than the understanding of concepts. An alternative assignment format was proposed which requires students to identify and explain mistakes in a given set of workings…

College Textbook Reading Assignments and Class Time Activity

ERIC Educational Resources Information Center

Aagaard, Lola; Conner, Timothy W., II.; Skidmore, Ronald L.

2014-01-01

A convenient cluster sample of 105 undergraduate students at a regional university in the midsouth completed a survey regarding their use of college textbooks, what strategies might increase the likelihood of their reading textbook assignments, and their preference for how class time was used. Descriptive analysis was conducted on the results and…

Detention as a Deterrent for Late Assignments: A Study.

ERIC Educational Resources Information Center

Conover, Pamela J.

To gauge the impact of after-school student detention on punctual completion of homework, on detained student grades, and on student self-esteem, fourth- through sixth-grade students from a school with an after-school detention policy for late or incomplete assignments were studied. Interviews were conducted with the four fourth-, fifth-, and…

Turnaround Time and Market Capacity in Contract Cheating

ERIC Educational Resources Information Center

Wallace, Melisa J.; Newton, Philip M.

2014-01-01

Contract cheating is the process whereby students auction off the opportunity for others to complete assignments for them. It is an apparently widespread yet under-researched problem. One suggested strategy to prevent contract cheating is to shorten the turnaround time between the release of assignment details and the submission date, thus making…

NMR assignments of juvenile hormone binding protein in complex with JH III.

PubMed

Suzuki, Rintaro; Tase, Akira; Fujimoto, Zui; Shiotsuki, Takahiro; Yamazaki, Toshimasa

2009-06-01

A hemolymph juvenile hormone binding protein (JHBP) shuttles hydrophobic JH, a key hormone in regulation of the insect life cycle, from the site of the JH biosynthesis to the cells of target organs. We report complete NMR chemical shift assignments of Bombyx mori JHBP in the JH III-bound state.

Neutron cross sections. Volume I. Resonance parameters

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

Mughabghab, S.F.; Garber, D.I.

1973-06-01

In contrast to earlier editions, which presented in compact form a summary of the complete store of the neutron data files, this edition aims to provide those portions of neutron data considered to be of prime importance and best suited for inclusion in ready reference form. This volume contains thermal cross sections, resonance properties, resonance parameters, and bibliography for nuclides from H to /sup 257/Fm. Notation and nomenclature, considerations involved in the recommendations, and a table of energyordered resonances are also included. (RWR)

Learning Gains from a Recurring "Teach and Question" Homework Assignment in a General Biology Course: Using Reciprocal Peer Tutoring Outside Class.

PubMed

Bailey, E G; Baek, D; Meiling, J; Morris, C; Nelson, N; Rice, N S; Rose, S; Stockdale, P

2018-06-01

Providing students with one-on-one interaction with instructors is a big challenge in large courses. One solution is to have students interact with their peers during class. Reciprocal peer tutoring (RPT) is a more involved interaction that requires peers to alternate the roles of "teacher" and "student." Theoretically, advantages for peer tutoring include the verbalization and questioning of information and the scaffolded exploration of material through social and cognitive interaction. Studies on RPT vary in their execution, but most require elaborate planning and take up valuable class time. We tested the effectiveness of a "teach and question" (TQ) assignment that required student pairs to engage in RPT regularly outside class. A quasi-experimental design was implemented: one section of a general biology course completed TQ assignments, while another section completed a substitute assignment requiring individuals to review course material. The TQ section outperformed the other section by ∼6% on exams. Session recordings were coded to investigate correlation between TQ quality and student performance. Asking more questions was the characteristic that best predicted exam performance, and this was more predictive than most aspects of the course. We propose the TQ as an easy assignment to implement with large performance gains.

PVT Degradation Studies: NMR Analysis

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

Cho, Herman M.; Kouzes, Richard T.

Under certain environmental conditions, polyvinyl toluene (PVT) plastic scintillator has been observed to undergo internal fogging. Nuclear magnetic resonance spectroscopy has been used to elucidate the state of water inside the PVT. The deuterium NMR results show that water absorbed by PVT under warm, humid conditions enters several distinct environments, and when the PVT is transferred from incubation to ambient temperature and humidity the water is lost on a time scale of a few hours from these samples. Most of the deuterium NMR peaks can be assigned to bulk liquid water, but almost 35% of the detected signal intensity ismore » contained in a resonance that resembles spectra of water contained in nanometer-scale pores in mesoporous carbon.« less

Increasing Text Comprehension and Graphic Note Taking Using a Partial Graphic Organizer

ERIC Educational Resources Information Center

Robinson, Daniel H.; Katayama, Andrew D.; Beth, Alicia; Odom, Susan; Hsieh, Ya-Ping; Vanderveen, Arthur

2006-01-01

In 3 quasi-experiments using intact classrooms and 1 true experiment using random assignment, students completed partially complete graphic organizers (GOs) or studied complete GOs that covered course content. The partial task led to increased overall examination performance in all experiments. Also, the authors measured students' note-taking…

15 CFR 200.110 - Priorities and time of completion.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Priorities and time of completion. 200..., SERVICES, PROCEDURES, AND FEES § 200.110 Priorities and time of completion. Schedule work assignments for calibrations and other tests will generally be made in the order in which confirmed requests are received...

Implementation of a Biaxial Resonant Fatigue Test Method on a Large Wind Turbine Blade

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

Snowberg, D.; Dana, S.; Hughes, S.

2014-09-01

A biaxial resonant test method was utilized to simultaneously fatigue test a wind turbine blade in the flap and edge (lead-lag) direction. Biaxial resonant blade fatigue testing is an accelerated life test method utilizing oscillating masses on the blade; each mass is independently oscillated at the respective flap and edge blade resonant frequency. The flap and edge resonant frequency were not controlled, nor were they constant for this demonstrated test method. This biaxial resonant test method presented surmountable challenges in test setup simulation, control and data processing. Biaxial resonant testing has the potential to complete test projects faster than single-axismore » testing. The load modulation during a biaxial resonant test may necessitate periodic load application above targets or higher applied test cycles.« less

Calculation of the spontaneous cyclotron emissivity using the complete relativistic resonance condition

NASA Technical Reports Server (NTRS)

Freund, H. P.; Wu, C. S.; Gaffey, J. D., Jr.

1984-01-01

An expression for the spectral emissivity of spontaneous synchrotron radiation for a plasma which consists of both thermal and suprathermal electron components is derived using the complete relativistic cyclotron resonance condition. The expression is valid over all angles of propagation. The result is applied to the study of the emission of radiation from an energetic population of electrons with a loss-cone distribution in a relatively low-density plasma (i.e., the electron plasma frequency is less than the cyclotron frequency).

Assessment of Prospectively Assigned Likert Scores for Targeted Magnetic Resonance Imaging-Transrectal Ultrasound Fusion Biopsies in Patients with Suspected Prostate Cancer.

PubMed

Costa, Daniel N; Lotan, Yair; Rofsky, Neil M; Roehrborn, Claus; Liu, Alexander; Hornberger, Brad; Xi, Yin; Francis, Franto; Pedrosa, Ivan

2016-01-01

We assess the performance of prospectively assigned magnetic resonance imaging based Likert scale scores for the detection of clinically significant prostate cancer, and analyze the pre-biopsy imaging variables associated with increased cancer detection using targeted magnetic resonance imaging-transrectal ultrasound fusion biopsy. In this retrospective review of prospectively generated data including men with abnormal multiparametric prostate magnetic resonance imaging (at least 1 Likert score 3 or greater lesion) who underwent subsequent targeted magnetic resonance imaging-transrectal ultrasound fusion biopsy, we determined the association between different imaging variables (Likert score, lesion size, lesion location, prostate volume, radiologist experience) and targeted biopsy positivity rate. We also compared the detection of clinically significant cancer according to Likert scale scores. Tumors with high volume (50% or more of any core) Gleason score 3+4 or any tumor with greater Gleason score were considered clinically significant. Each lesion served as the elementary unit for analysis. We used logistic regression for univariate and multivariate (stepwise selection) analysis to assess for an association between targeted biopsy positivity rate and each tested variable. The relationship between Likert scale and Gleason score was evaluated using the Spearman correlation coefficient. A total of 161 men with 244 lesions met the study eligibility criteria. Targeted biopsies diagnosed cancer in 41% (66 of 161) of the men and 41% (99 of 244) of the lesions. The Likert score was the strongest predictor of targeted biopsy positivity (OR 3.7, p <0.0001). Other imaging findings associated with a higher targeted biopsy positivity rate included smaller prostate volume (OR 0.7, p <0.01), larger lesion size (OR 2.2, p <0.001) and anterior location (OR 2.0, p=0.01). On multiple logistic regression analysis Likert score, lesion size and prostate volume were significant predictors of targeted biopsy positivity. Higher Likert scores were also associated with increased detection of clinically significant tumors (p <0.0001). The Likert scale score used to convey the degree of suspicion on multiparametric magnetic resonance imaging is the strongest predictor of targeted biopsy positivity and of the presence of clinically significant tumor. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Combination of liquid chromatography-Fourier transform ion cyclotron resonance-mass spectrometry with 13C-labeling for chemical assignment of sulfur-containing metabolites in onion bulbs.

PubMed

Nakabayashi, Ryo; Sawada, Yuji; Yamada, Yutaka; Suzuki, Makoto; Hirai, Masami Yokota; Sakurai, Tetsuya; Saito, Kazuki

2013-02-05

Phytochemicals containing heteroatoms (N, O, S, and halogens) often have biological activities that are beneficial to humans. Although targeted profiling methods for such phytochemicals are expected to contribute to rapid chemical assignments, thus making phytochemical genomics and crop breeding much more efficient, there are few profiling methods for the metabolites. Here, as an ultrahigh performance approach, we propose a practical profiling method for S-containing metabolites (S-omics) using onions (Allium cepa) as a representative species and (12)C- and (13)C-based mass spectrometry (MS) and tandem mass spectrometry (MS/MS) analyses by liquid chromatography-Fourier transform ion cyclotron resonance-mass spectrometry (LC-FTICR-MS). Use of the ultrahigh quality data from FTICR-MS enabled simplifying the previous methods to determine specific elemental compositions. MS analysis with a resolution of >250,000 full width at half-maximum and a mass accuracy of <1 ppm can distinguish S-containing monoisotopic ions from other ions on the basis of the natural abundance of (32)S and (34)S and the mass differences among the S isotopes. Comprehensive peak picking using the theoretical mass difference (1.99579 Da) between (32)S-containing monoisotopic ions and their (34)S-substituted counterparts led to the assignment of 67 S-containing monoisotopic ions from the (12)C-based MS spectra, which contained 4693 chromatographic ions. The unambiguous elemental composition of 22 ions was identified through comparative analysis of the (12)C- and (13)C-based MS spectra. Finally, of these, six ions were found to be derived from S-alk(en)ylcysteine sulfoxides and glutathione derivatives. This S-atom-driven approach afforded an efficient chemical assignment of S-containing metabolites, suggesting its potential application for screening not only S but also other heteroatom-containing metabolites in MS-based metabolomics.

Feshbach resonances in the exit channel of the F + CH3OH → HF + CH3O reaction observed using transition-state spectroscopy

NASA Astrophysics Data System (ADS)

Weichman, Marissa L.; Devine, Jessalyn A.; Babin, Mark C.; Li, Jun; Guo, Lifen; Ma, Jianyi; Guo, Hua; Neumark, Daniel M.

2017-10-01

The transition state governs how chemical bonds form and cleave during a chemical reaction and its direct characterization is a long-standing challenge in physical chemistry. Transition state spectroscopy experiments based on negative-ion photodetachment provide a direct probe of the vibrational structure and metastable resonances that are characteristic of the reactive surface. Dynamical resonances are extremely sensitive to the topography of the reactive surface and provide an exceptional point of comparison with theory. Here we study the seven-atom F + CH3OH → HF + CH3O reaction using slow photoelectron velocity-map imaging spectroscopy of cryocooled CH3OHF- anions. These measurements reveal spectral features associated with a manifold of vibrational Feshbach resonances and bound states supported by the post-transition state potential well. Quantum dynamical calculations yield excellent agreement with the experimental results, allow the assignment of spectral structure and demonstrate that the key dynamics of complex bimolecular reactions can be captured with a relatively simple theoretical framework.

Feshbach resonances in the exit channel of the F + CH3OH → HF + CH3O reaction observed using transition-state spectroscopy.

PubMed

Weichman, Marissa L; DeVine, Jessalyn A; Babin, Mark C; Li, Jun; Guo, Lifen; Ma, Jianyi; Guo, Hua; Neumark, Daniel M

2017-10-01

The transition state governs how chemical bonds form and cleave during a chemical reaction and its direct characterization is a long-standing challenge in physical chemistry. Transition state spectroscopy experiments based on negative-ion photodetachment provide a direct probe of the vibrational structure and metastable resonances that are characteristic of the reactive surface. Dynamical resonances are extremely sensitive to the topography of the reactive surface and provide an exceptional point of comparison with theory. Here we study the seven-atom F + CH 3 OH → HF + CH 3 O reaction using slow photoelectron velocity-map imaging spectroscopy of cryocooled CH 3 OHF - anions. These measurements reveal spectral features associated with a manifold of vibrational Feshbach resonances and bound states supported by the post-transition state potential well. Quantum dynamical calculations yield excellent agreement with the experimental results, allow the assignment of spectral structure and demonstrate that the key dynamics of complex bimolecular reactions can be captured with a relatively simple theoretical framework.

Comprehensive analysis of oil sands processed water by direct-infusion Fourier-transform ion cyclotron resonance mass spectrometry with and without offline UHPLC sample prefractionation.

PubMed

Nyakas, Adrien; Han, Jun; Peru, Kerry M; Headley, John V; Borchers, Christoph H

2013-05-07

Oil sands processed water (OSPW) is the main byproduct of the large-scale bitumen extraction activity in the Athabasca oil sands region (Alberta, Canada). We have investigated the acid-extractable fraction (AEF) of OSPW by extraction-only (EO) direct infusion (DI) negative-ion mode electrospray ionization (ESI) on a 12T-Fourier transform ion cyclotron resonance mass spectrometer (FTICR-MS), as well as by offline ultrahigh performance liquid chromatography (UHPLC) followed by DI-FTICR-MS. A preliminary offline UHPLC separation into 8 fractions using a reversed-phase C4 column led to approximately twice as many detected peaks and identified compounds (973 peaks versus 2231 peaks, of which 856 and 1734 peaks, respectively, could be assigned to chemical formulas based on accurate mass measurements). Conversion of these masses to the Kendrick mass scale allowed the straightforward recognition of homologues. Naphthenic (CnH2n+zO2) and oxy-naphthenic (CnH2n+zOx) acids represented the largest group of molecules with assigned formulas (64%), followed by sulfur-containing compounds (23%) and nitrogen-containing compounds (8%). Pooling of corresponding fractions from two consecutive offline UHPLC runs prior to MS analysis resulted in ~50% more assignments than a single injection, resulting in 3-fold increase of identifications compared to EO-DI-FTICR-MS using the same volume of starting material. Liquid-liquid extraction followed by offline UHPLC fractionation thus holds enormous potential for a more comprehensive profiling of OSPW, which may provide a deeper understanding of its chemical nature and environmental impact.

Specific labeling and assignment strategies of valine methyl groups for NMR studies of high molecular weight proteins.

PubMed

Mas, Guillaume; Crublet, Elodie; Hamelin, Olivier; Gans, Pierre; Boisbouvier, Jérôme

2013-11-01

The specific protonation of valine and leucine methyl groups in proteins is typically achieved by overexpressing proteins in M9/D2O medium supplemented with either labeled α-ketoisovalerate for the labeling of the four prochiral methyl groups or with 2-acetolactate for the stereospecific labeling of the valine and leucine side chains. However, when these labeling schemes are applied to large protein assemblies, significant overlap between the correlations of the valine and leucine methyl groups occurs, hampering the analysis of 2D methyl-TROSY spectra. Analysis of the leucine and valine biosynthesis pathways revealed that the incorporation of labeled precursors in the leucine pathway can be inhibited by the addition of exogenous l-leucine-d10. We exploited this property to label stereospecifically the pro-R and pro-S methyl groups of valine with minimal scrambling to the leucine residues. This new labeling protocol was applied to the 468 kDa homododecameric peptidase TET2 to decrease the complexity of its NMR spectra. All of the pro-S valine methyl resonances of TET2 were assigned by combining mutagenesis with this innovative labeling approach. The assignments were transferred to the pro-R groups using an optimally labeled sample and a set of triple resonance experiments. This improved labeling scheme enables us to overcome the main limitation of overcrowding in the NMR spectra of prochiral methyl groups, which is a prerequisite for the site-specific measurement of the structural and dynamic parameters or for the study of interactions in very large protein assemblies.

Unusual heme iron-lipid acyl chain coordination in Escherichia coli flavohemoglobin.

PubMed

D'Angelo, Paola; Lucarelli, Debora; della Longa, Stefano; Benfatto, Maurizio; Hazemann, Jean Louis; Feis, Alessandro; Smulevich, Giulietta; Ilari, Andrea; Bonamore, Alessandra; Boffi, Alberto

2004-06-01

Escherichia coli flavohemoglobin is endowed with the notable property of binding specifically unsaturated and/or cyclopropanated fatty acids both as free acids or incorporated into a phospholipid molecule. Unsaturated or cyclopropanated fatty acid binding to the ferric heme results in a spectral change observed in the visible absorption, resonance Raman, extended x-ray absorption fine spectroscopy (EXAFS), and x-ray absorption near edge spectroscopy (XANES) spectra. Resonance Raman spectra, measured on the flavohemoglobin heme domain, demonstrate that the lipid (linoleic acid or total lipid extracts)-induced spectral signals correspond to a transition from a five-coordinated (typical of the ligand-free protein) to a hexacoordinated, high spin heme iron. EXAFS and XANES measurements have been carried out both on the lipid-free and on the lipid-bound protein to assign the nature of ligand in the sixth coordination position of the ferric heme iron. EXAFS data analysis is consistent with the presence of a couple of atoms in the sixth coordination position at 2.7 A in the lipid-bound derivative (bonding interaction), whereas a contribution at 3.54 A (nonbonding interaction) can be singled out in the lipid-free protein. This last contribution is assigned to the CD1 carbon atoms of the distal LeuE11, in full agreement with crystallographic data on the lipid-free protein at 1.6 A resolution obtained in the present work. Thus, the contributions at 2.7 A distance from the heme iron are assigned to a couple of carbon atoms of the lipid acyl chain, possibly corresponding to the unsaturated carbons of the linoleic acid.

Vibrational Spectroscopy of CO2- Radical Anion in Water

NASA Astrophysics Data System (ADS)

Janik, Ireneusz; Tripathi, G. N. R.

2016-06-01

The reductive conversion of CO2 into industrial products (e.g., oxalic acid, formic acid, and methanol) can occur via aqueous CO2- as a transient intermediate. While the formation, structure and reaction pathways of this radical anion have been modelled for decades using various spectroscopic and theoretical approaches, we present here, for the first time, a vibrational spectroscopic investigation in liquid water, using pulse radiolysis time-resolved resonance Raman spectroscopy for its preparation and observation. Excitation of the radical in resonance with its 235 nm absorption displays a transient Raman band at 1298 wn, attributed to the symmetric CO stretch, which is at 45 wn higher frequency than in inert matrices. Isotopic substitution at C (13CO2-) shifts the frequency downwards by 22 wn which confirms its origin and the assignment. A Raman band of moderate intensity compared to the stronger 1298 wn band also appears at 742 wn, and is assignable to the OCO bending mode. A reasonable resonance enhancement of this mode is possible only in a bent CO2-(C2v/Cs) geometry. These resonance Raman features suggest a strong solute-solvent interaction, the water molecules acting as constituents of the radical structure, rather than exerting a minor solvent perturbation. However, there is no evidence of the non-equivalence (Cs) of the two CO bonds. A surprising resonance Raman feature is the lack of overtones of the symmetric CO stretch, which we interpret due to the detachment of the electron from the CO2- moiety towards the solvation shell. Electron detachment occurs at the energies of 0.28+/-0.03 eV or higher with respect to the zero point energy of the ground electronic state. The issue of acid-base equilibrium of the radical which has been in contention for decades, as reflected in a wide variation in the reported pKa (-0.2 to 3.9), has been resolved. A value of 3.4+/-0.2 measured in this work is consistent with the vibrational properties, bond structure and charge distribution in aqueous CO2-.

Panels with low-Q-factor resonators with theoretically infinite sound-proofing ability at a single frequency

NASA Astrophysics Data System (ADS)

Lazarev, L. A.

2015-07-01

An infinite panel with two types of resonators regularly installed on it is theoretically considered. Each resonator is an air-filled cavity hermetically closed by a plate, which executes piston vibrations. The plate and air inside the cavity play the roles of mass and elasticity, respectively. Every other resonator is reversed. At a certain ratio between the parameters of the resonators at the tuning frequency of the entire system, the acoustic-pressure force that directly affects the panel can be fully compensated by the action forces of the resonators. In this case, the sound-proofing ability (transmission loss) tends to infinity. The presented calculations show that a complete transmission-loss effect can be achieved even with low- Q resonators.

Effects of 8 weeks of continuous positive airway pressure on abdominal adiposity in obstructive sleep apnoea.

PubMed

Sivam, Sheila; Phillips, Craig L; Trenell, Michael I; Yee, Brendon J; Liu, Peter Y; Wong, Keith K; Grunstein, Ronald R

2012-10-01

The aim of the present study was to investigate the effect of continuous positive airway pressure (CPAP) treatment on regional adipose tissue distribution in patients with moderate or severe obstructive sleep apnoea. Patients received both therapeutic and sham CPAP in a random order for 2 months each with an intervening 1-month washout. Abdominal subcutaneous, visceral and liver fat were quantified using magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). Liver enzymes and plasma glucose were also determined. Measurements were obtained at baseline and at the end of both treatment arms. 38 eligible patients were randomly assigned to a treatment order, with 27 patients having complete MRI/MRS data. No significant difference was observed in subcutaneous (-28.6 cm(3); p=0.49) or visceral (-16.8 cm(3); p=0.59) adipose tissue, intrahepatic lipid (-0.2%; p=0.21), or fasting glucose measurements (-0.1 mmol·L(-1); p=0.46) between treatment modalities. Alkaline phosphatase decreased (-3.1 U·L(-1); p=0.02) while on therapeutic CPAP compared with sham CPAP but other liver enzymes, including aspartate aminotransferase (0.3 U·L(-1); p=0.82), alanine aminotransferase (1.34 U·L(-1); p=0.59) and γ-glutamyltransferase (-2.3 U·L(-1); p=0.33), remained unchanged. In this first randomised, sham-controlled trial, there was no change in adipose tissue distribution after 8 weeks of therapeutic CPAP compared with 8 weeks of sham CPAP. Longer duration of CPAP use may be necessary to demonstrate a difference.

Radiation therapy planning and simulation with magnetic resonance images

NASA Astrophysics Data System (ADS)

Boettger, Thomas; Nyholm, Tufve; Karlsson, Magnus; Nunna, Chandrasekhar; Celi, Juan Carlos

2008-03-01

We present a system which allows for use of magnetic resonance (MR) images as primary RT workflow modality alone and no longer limits the user to computed tomography data for radiation therapy (RT) planning, simulation and patient localization. The single steps for achieving this goal are explained in detail. For planning two MR data sets, MR1 and MR2 are acquired sequentially. For MR1 a standardized Ultrashort TE (UTE) sequence is used enhancing bony anatomy. The sequence for MR2 is chosen to get optimal contrast for the target and the organs at risk for each individual patient. Both images are naturally in registration, neglecting elastic soft tissue deformations. The planning software first automatically extracts skin and bony anatomy from MR1. The user can semi-automatically delineate target structures and organs at risk based on MR1 or MR2, associate all segmentations with MR1 and create a plan in the coordinate system of MR1. Projections similar to digitally reconstructed radiographs (DRR) enhancing bony anatomy are calculated from the MR1 directly and can be used for iso-center definition and setup verification. Furthermore we present a method for creating a Pseudo-CT data set which assigns electron densities to the voxels of MR1 based on the skin and bone segmentations. The Pseudo-CT is then used for dose calculation. Results from first tests under clinical conditions show the feasibility of the completely MR based workflow in RT for necessary clinical cases. It needs to be investigated in how far geometrical distortions influence accuracy of MR-based RT planning.

Critical thinking and reflection exercises in a biochemistry course to improve prospective health professions students' attitudes toward physician-pharmacist collaboration.

PubMed

Van Winkle, Lon J; Cornell, Susan; Fjortoft, Nancy; Bjork, Bryan C; Chandar, Nalini; Green, Jacalyn M; La Salle, Sophie; Viselli, Susan M; Burdick, Paulette; Lynch, Sean M

2013-10-14

To determine the impact of performing critical-thinking and reflection assignments within interdisciplinary learning teams in a biochemistry course on pharmacy students' and prospective health professions students' collaboration scores. Pharmacy students and prospective medical, dental, and other health professions students enrolled in a sequence of 2 required biochemistry courses. They were randomly assigned to interdisciplinary learning teams in which they were required to complete case assignments, thinking and reflection exercises, and a team service-learning project. Students were asked to complete the Scale of Attitudes Toward Physician-Pharmacist Collaboration prior to the first course, following the first course, and following the second course. The physician-pharmacist collaboration scores of prospective health professions students increased significantly (p<0.001). Having prospective health professions students work in teams with pharmacy students to think and reflect in and outside the classroom improves their attitudes toward physician-pharmacist collaboration.

Electronic Measurement of Rock Stress

DTIC Science & Technology

atomic resonances that are pressure-sensitive. Nuclear quadrupole resonance ( NQR ) appeared clearly applicable, since no magnetic aligning field is needed...there are several common NQR -active nuclear species in major rock-forming minerals, and rf magnetic fields between 0.3 and 3 megahertz (the resonant...comprehensive literature search has been completed on NQR in minerals, which shows that aluminum-27 and a few other elements in feldspars are promising

Negative ion resonance measurements in the autoionizing region of helium measured across the complete angular scattering range (0°-180°)

NASA Astrophysics Data System (ADS)

Ward, R.; Cubric, D.; Bowring, N.; King, G. C.; Read, F. H.; Fursa, D. V.; Bray, I.

2013-02-01

Excitation function measurements for the decay of the 2s22p 2P and 2s2p2 2D triply excited negative ion resonances in helium to singly excited n = 2 states have been measured. These excitation functions have been determined across the complete angular range (0-180°) using a magnetic angle changer with a soft-iron core. The convergent close-coupling method has been used to calculate the cross sections, with the underlying complexity of the problem not yet being able to be fully resolved. Agreement between the present experimental data and previous experimental data is good, with these excitation functions confirming the presence of an unusual (2s22p)2P resonance behaviour in the 21S channel at 90°, where this would not usually be expected. Resonance energy and width values have been obtained, with a mean energy for the (2s22p)2P resonance of 57.20 ± 0.08 eV and a mean width of 73 ± 20 meV, and a mean energy of the (2s2p2)2D resonance of 58.30 ± 0.08 eV and a mean width of 59 ± 27 meV. Resonant cross section and ρ2 values have been calculated across the angular range for the first time, providing angular distribution data on decay propensities for both resonances.

Bone quantitative susceptibility mapping using a chemical species-specific R2* signal model with ultrashort and conventional echo data.

PubMed

Dimov, Alexey V; Liu, Zhe; Spincemaille, Pascal; Prince, Martin R; Du, Jiang; Wang, Yi

2018-01-01

To develop quantitative susceptibility mapping (QSM) of bone using an ultrashort echo time (UTE) gradient echo (GRE) sequence for signal acquisition and a bone-specific effective transverse relaxation rate ( R2*) to model water-fat MR signals for field mapping. Three-dimensional radial UTE data (echo times ≥ 40 μs) was acquired on a 3 Tesla scanner and fitted with a bone-specific signal model to map the chemical species and susceptibility field. Experiments were performed ex vivo on a porcine hoof and in vivo on healthy human subjects (n = 7). For water-fat separation, a bone-specific model assigning R2* decay mostly to water was compared with the standard models that assigned the same decay for both fat and water. In the ex vivo experiment, bone QSM was correlated with CT. Compared with standard models, the bone-specific R2* method significantly reduced errors in the fat fraction within the cortical bone in all tested data sets, leading to reduced artifacts in QSM. Good correlation was found between bone CT and QSM values in the porcine hoof (R 2  = 0.77). Bone QSM was successfully generated in all subjects. The QSM of bone is feasible using UTE with a conventional echo time GRE acquisition and a bone-specific R2* signal model. Magn Reson Med 79:121-128, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Joint experimental and computational 17O solid state NMR study of Brownmillerite Ba2In2O5.

PubMed

Dervişoğlu, Rıza; Middlemiss, Derek S; Blanc, Frédéric; Holmes, Lesley A; Lee, Yueh-Lin; Morgan, Dane; Grey, Clare P

2014-02-14

Structural characterization of Brownmillerite Ba2In2O5 was achieved by an approach combining experimental solid-state NMR spectroscopy, density functional theory (DFT) energetics, and GIPAW NMR calculations. While in the previous study of Ba2In2O5 by Adler et al. (S. B. Adler, J. A. Reimer, J. Baltisberger and U. Werner, J. Am. Chem. Soc., 1994, 116, 675-681), three oxygen resonances were observed in the (17)O NMR spectra and assigned to the three crystallographically unique O sites, the present high resolution (17)O NMR measurements under magic angle spinning (MAS) find only two resonances. The resonances have been assigned using first principles (17)O GIPAW NMR calculations to the combination of the O ions connecting the InO4 tetrahedra and the O ions in equatorial sites in octahedral InO6 coordination, and to the axial O ions linking the four- and six-fold coordinated In(3+) ions. Possible structural disorder was investigated in two ways: firstly, by inclusion of the high-energy structure also previously studied by Mohn et al. (C. E. Mohn, N. L. Allan, C. L. Freeman, P. Ravindran and S. Stølen, J. Solid State Chem., 2005, 178, 346-355), where the structural O vacancies are stacked rather than staggered as in Brownmillerite and, secondly, by exploring structures derived from the ground-state structure but with randomly perturbed atomic positions. There is no noticeable NMR evidence for any substantial occupancy of the high-energy structure at room temperature.

Assignments of /sup 1/H nuclear magnetic resonances of the cystyl, asparaginyl, and aromatic residues of arginine vasopressin in D/sub 2/O. A comparison with lysine vasopressin and oxytocin in terms of solution conformation

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

Wyssbrod, H.R.; Fischman, A.J.; Live, D.H.

1979-07-18

The resonances of the C/sup ..cap alpha../ and C/sup ..beta../ protons of the cystyl, asparaginyl, and aromatic residues of (8-arginine)vasopressin (AVP) in D/sub 2/O at pD 3.8 and 20/sup 0/C were assigned in a rigorous manner by the use of isotopic isomers of AVP that contain specific replacements of protons by deuterons and by comparison of /sup 1/H NMR characteristics of AVP to those of (8-lysine)vasopressin (LVP) and oxytocin (OT). Although there is extensive overlap of resonances of C/sup ..beta../ protons even at 360 MHz, all of the chemical shifts of these protons and most of the couplings between themmore » and their vicinal C/sup ..cap alpha../ protons could be determined, at least to a first approximation. It was concluded that the cyclic moieties (residues 1-6) of AVP, LVP, and OT possess essentially the same overall backbone conformation, and that the side-chain conformation - or rotamer populations - about the C/sup ..cap alpha../-C/sup ..beta../ bonds of the cystyl residue (positions 1 and 6), the tyrosyl residue (position 2), and the asparaginyl residue (position 5) are similar. This study indicates that selective replacements of C/sup ..beta../ protons by deuterons are necessary to improve the accuracy of coupling constants extracted from 360-MHz spectra of a AVP for use in conformational analysis.« less

Using Content Reading Assignments in a Psychology Course to Teach Critical Reading Skills

ERIC Educational Resources Information Center

Van Camp, Debbie; Van Camp, Wesley

2013-01-01

Liberal arts students are expected to graduate college with fully developed critical reading and writing skills. However, for a variety of reasons these skills are not always as well developed as they might be--both during and upon completion of college. This paper describes a reading assignment that was designed to increase students'…

Looking for a Possible Framework to Teach Contemporary Art in Primary School

ERIC Educational Resources Information Center

Vahter, Edna

2016-01-01

Traditionally, the learning of arts in the Estonian primary school has meant completion of practical assignments given by the teacher. The new national curriculum for basic school adopted in 2010 sets out new requirements for art education where the emphasis, in addition to practical assignments, is on discussion and understanding of art. The…

Integrating Multicultural Children's Math Books into Kindergarten through Sixth-Grade Classrooms: Preservice Teachers' Reflections

ERIC Educational Resources Information Center

Harding, Jenni; Hbaci, Ilham; Loyd, Stacy; Hamilton, Boni

2017-01-01

This case study of mathematics instruction using children's literature reports on the experiences 47 elementary preservice teachers had in their mathematics methods course while completing a microteaching assignment. As part of the microteaching assignment, preservice teachers were required to plan and teach mathematics lessons based on children's…

Effects of Higher and Lower Level Writing-To-Learn Assignments on Higher and Lower Level Examination Questions

ERIC Educational Resources Information Center

Nevid, Jeffrey S.; Ambrose, Michael A.; Pyun, Yea Seul

2017-01-01

Our study examined whether brief writing-to-learn assignments linked to lower and higher levels in Bloom's taxonomy affected performance differentially on examination performance in assessing these skill levels. Using a quasi-random design, 91 undergraduate students in an introductory psychology class completed eight lower level and eight higher…

This Old Thing? Using Old Laboratory Equipment to Enhance Student Learning

ERIC Educational Resources Information Center

Elcoro, Mirari; McCarley, Nancy

2015-01-01

Using a surplus of older laboratory instruments, 48 students in a learning and behavior course completed an assignment designed to provide an introduction to the history and use of some instruments in psychology. Students worked in pairs, were assigned one instrument, and created labels in which they identified several keys characteristics of an…

Method for routing events from key strokes in a multi-processing computer systems

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

Rhodes, D.A.; Rustici, E.; Carter, K.H.

1990-01-23

The patent describes a method of routing user input in a computer system which concurrently runs a plurality of processes. It comprises: generating keycodes representative of keys typed by a user; distinguishing generated keycodes by looking up each keycode in a routing table which assigns each possible keycode to an individual assigned process of the plurality of processes, one of which processes being a supervisory process; then, sending each keycode to its assigned process until a keycode assigned to the supervisory process is received; sending keycodes received subsequent to the keycode assigned to the supervisory process to a buffer; next,more » providing additional keycodes to the supervisory process from the buffer until the supervisory process has completed operation; and sending keycodes stored in the buffer to processes assigned therewith after the supervisory process has completedoperation.« less

Three-Body Nature of N* and Δ* Resonances from Sequential Decay Chains

NASA Astrophysics Data System (ADS)

Thiel, A.; Sokhoyan, V.; Gutz, E.; van Pee, H.; Anisovich, A. V.; Bacelar, J. C. S.; Bantes, B.; Bartholomy, O.; Bayadilov, D.; Beck, R.; Beloglazov, Yu.; Castelijns, R.; Crede, V.; Dutz, H.; Elsner, D.; Ewald, R.; Frommberger, F.; Fuchs, M.; Funke, Ch.; Gregor, R.; Gridnev, A.; Hillert, W.; Hoffmeister, Ph.; Horn, I.; Jaegle, I.; Junkersfeld, J.; Kalinowsky, H.; Kammer, S.; Kleber, V.; Klein, Frank; Klein, Friedrich; Klempt, E.; Kotulla, M.; Krusche, B.; Lang, M.; Löhner, H.; Lopatin, I.; Lugert, S.; Mertens, T.; Messchendorp, J. G.; Metag, V.; Metsch, B.; Nanova, M.; Nikonov, V.; Novinski, D.; Novotny, R.; Ostrick, M.; Pant, L.; Pfeiffer, M.; Piontek, D.; Roy, A.; Sarantsev, A. V.; Schmidt, Ch.; Schmieden, H.; Shende, S.; Süle, A.; Sumachev, V. V.; Szczepanek, T.; Thoma, U.; Trnka, D.; Varma, R.; Walther, D.; Wendel, Ch.; Wilson, A.; Cbelsa/Taps Collaboration

2015-03-01

The N π0π0 decays of positive-parity N* and Δ* resonances at about 2 GeV are studied at ELSA by photoproduction of two neutral pions off protons. The data reveal clear evidence for several intermediate resonances: Δ (1232 ) , N (1520 )3 /2- , and N (1680 )5 /2+ , with spin parities JP=3 /2+ , 3 /2- , and 5 /2+. The partial wave analysis (within the Bonn-Gatchina approach) identifies N (1440 )1 /2+ and the N (π π )S wave (abbreviated as N σ here) as further isobars and assigns the final states to the formation of nucleon and Δ resonances and to nonresonant contributions. We observe the known Δ (1232 )π decays of Δ (1910 )1 /2+ , Δ (1920 )3 /2+, Δ (1905 )5 /2+, Δ (1950 )7 /2+, and of the corresponding spin-parity series in the nucleon sector, N (1880 )1 /2+, N (1900 )3 /2+, N (2000 )5 /2+, and N (1990 )7 /2+ . For the nucleon resonances, these decay modes are reported here for the first time. Further new decay modes proceed via N (1440 )1 /2+π , N (1520 )3 /2-π , N (1680 )5 /2+π , and N σ . The latter decay modes are observed in the decay of N* resonances and at most weakly in Δ* decays. It is argued that these decay modes provide evidence for a 3-quark nature of N* resonances rather than a quark-diquark structure.

Autoionization structure of nitric oxide (NO) at the first ionization limit

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

Miescher, E.; Lee, Y.T.; Guertler, P.

1978-03-15

A new and more detailed interpretation is given to the fine structure in the photoionization curve of cold NO observed by Ng, Mahan, and Lee. Resonances are assigned to autoionizing np and nddelta Rydberg levels which give prominent diffuse absorption bands in a spectrum recorded with the synchrotron radiation continuum. ..delta nu..<-1transitions in the vibrational autoionization process are substantiated.

Monoterpene Unknowns Identified Using IR, [to the first power]H-NMR, [to the thirteenth power]C-NMR, DEPT, COSY, and HETCOR

ERIC Educational Resources Information Center

Alty, Lisa T.

2005-01-01

A study identifies a compound from a set of monoterpenes using infrared (IR) and one-dimensional (1D) nuclear magnetic resonance (NMR) techniques. After identifying the unknown, each carbon and proton signal can be interpreted and assigned to the structure using the information in the two-dimensional (2D) NMR spectra, correlation spectroscopy…

FTIR (Fourier Transform Infrared) and FTNMR (Fourier Transform Nuclear Magnetic Resonance) Study of Organophosphorus Surface Reactions

DTIC Science & Technology

1987-09-01

broad band centered about 1140 cm - , (assigned to v(A1-F), 3 (b) no observable v(P=O), 0 (c) a new band at 1082 cm-f (assigned to J P "’i, and also O O...the growth of hydrolysis product can be followed by using either v((P)-G-C) at 999 cm -’ or vs(P0 2 ) at 1082 cm - , but the v(P-F) at about 870 cm-1 is...1180(m)1139(w) v(AI-F) -iI40(br) l!43(vw) 1109(vw) va(P 0 2 ) 1082 (m) 1103(w) 1026 v((P)-O-C) 1011 950(sh) 917 due to subtraction of silica band 900

The excited J = 01 Σu+ levels of D2: Measurements and ab initio quantum defect study

NASA Astrophysics Data System (ADS)

Glass-Maujean, M.; Jungen, Ch.; Dickenson, G. D.; de Oliveira, N.; Ubachs, W.

2016-02-01

The DESIRS beamline of the SOLEIL synchrotron facility, equipped with a vacuum ultraviolet Fourier-transform spectrometer has been used to measure P (N″ = 1) (N -N″ = - 1) absorption transitions of the D2 molecule. Some 44 P-lines were assigned and their transition frequencies determined up to excitation energies of 134,000 cm-1 above the ground state, thereby extending the earlier work by various authors, and considerably improving the spectral accuracy (<0.1 cm-1). The assignments have been aided by first principles multichannel quantum defect theory (MQDT) calculations. These calculations also provide predictions of the autoionization widths of the upper levels which agree well with the observed resonance widths.

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

Wemmer, D.E.; Kumar, N.V.; Metrione, R.M.

Toxin II from Radianthus paumotensis (Rp/sub II/) has been investigated by high-resolution NMR and chemical sequencing methods. Resonance assignments have been obtained for this protein by the sequential approach. NMR assignments could not be made consistent with the previously reported primary sequence for this protein, and chemical methods have been used to determine a sequence with which the NMR data are consistent. Analysis of the 2D NOE spectra shows that the protein secondary structure is comprised of two sequences of ..beta..-sheet, probably joined into a distorted continuous sheet, connected by turns and extended loops, without any regular ..cap alpha..-helical segments.more » The residues previously implicated in activity in this class of proteins, D8 and R13, occur in a loop region.« less

Spectroscopic study of jet-cooled indole-3-carbinol by laser desorption technique: Franck-Condon simulations and anharmonic calculations

NASA Astrophysics Data System (ADS)

Ahn, Ahreum; Min, Ahreum; Moon, Cheol Joo; Lee, Ji Hoon; Lee, Seung Jun; Warashina, Taichi; Ishiuchi, Shun-ichi; Fujii, Masaaki; Choi, Myong Yong

2015-10-01

The conformational structure of indole-3-carbinol (I3C) has been investigated in the gas phase for the first time using a laser desorption technique. A UV-UV hole-burning technique revealed the presence of a single conformer of I3C in the mass-selected resonant two-photon ionization spectrum. The assignment of the observed IR spectrum of I3C is inconclusive due to almost identically predicted IR frequencies of the two lowest energy conformers from harmonic calculations. A conclusive assignment for the conformer of I3C has been reported with an aid of performing anharmonic calculations and Franck-Condon simulations on the two lowest-energy conformers.

Experimental Evidence on the Effect of Childhood Investments on Postsecondary Attainment and Degree Completion

ERIC Educational Resources Information Center

Dynarski, Susan; Hyman, Joshua; Schanzenbach, Diane Whitmore

2013-01-01

This paper examines the effect of early childhood investments on college enrollment and degree completion. We used the random assignment in Project STAR (the Tennessee Student/Teacher Achievement Ratio experiment) to estimate the effect of smaller classes in primary school on college entry, college choice, and degree completion. We improve on…

Defect states in hexagonal boron nitride: Assignments of observed properties and prediction of properties relevant to quantum computation

NASA Astrophysics Data System (ADS)

Sajid, A.; Reimers, Jeffrey R.; Ford, Michael J.

2018-02-01

Key properties of nine possible defect sites in hexagonal boron nitride (h-BN), VN,VN -1,CN,VNO2 B,VNNB,VNCB,VBCN,VBCNS iN , and VNCBS iB , are predicted using density-functional theory and are corrected by applying results from high-level ab initio calculations. Observed h-BN electron-paramagnetic resonance signals at 22.4, 20.83, and 352.70 MHz are assigned to VN,CN, and VNO2 B , respectively, while the observed photoemission at 1.95 eV is assigned to VNCB . Detailed consideration of the available excited states, allowed spin-orbit couplings, zero-field splitting, and optical transitions is made for the two related defects VNCB and VBCN . VNCB is proposed for realizing long-lived quantum memory in h-BN. VBCN is predicted to have a triplet ground state, implying that spin initialization by optical means is feasible and suitable optical excitations are identified, making this defect of interest for possible quantum-qubit operations.

The adverse drug reaction reporting assignment for specialist oncology nurses: a preliminary evaluation of quality, relevance and educational value in a prospective cohort study.

PubMed

Schutte, Tim; van Eekeren, Rike; Richir, Milan; van Staveren, Jojanneke; van Puijenbroek, Eugène; Tichelaar, Jelle; van Agtmael, Michiel

2018-01-01

In a new prescribing qualification course for specialist oncology nurses, we thought that it is important to emphasize pharmacovigilance and adverse drug reaction (ADR) reporting. We aimed to develop and evaluate an ADR reporting assignment for specialist oncology nurses. The quality of report documentation was assessed with the "Clinical Documentation tool to assess Individual Case Safety Reports" (ClinDoc). The relevance of the reports was evaluated in terms of ADR seriousness, the listing for additional monitoring of the drug by European Medicines Agency (EMA), and lack of labelling information about the ADR. Nurses' opinions of the assignment were evaluated using an E-survey. Thirty-three ADRs were reported, 32 (97%) of which were well documented according to ClinDoc. Thirteen ADRs (39%) were "serious" according to CIOMS criteria. In five cases (15%), the suspect drugs were listed for additional monitoring by EMA and in seven cases (21%), the ADR was not mentioned in the Summary of Product Characteristics. Twenty-five (78.1%) of the 32 enrolled nurses completed the E-survey. Most were > 45 years of age (68%), female (92%) and had extensive clinical experience (6-33 years). All agreed or completely agreed that the reporting assignment was useful, that it fitted in daily practice and that it increased their attention for medication/patient safety. A large majority (84.0%) agreed the assignment changed how they dealt with ADRs. Specialist oncology nurses are capable of reporting ADRs, and they considered the assignment useful. The assignment yielded valuable, relevant, and well-documented ADR reports for pharmacovigilance practice.

A Comparison between Chocolate Milk and a Raw Milk Honey Solution’s Influence on Delayed Onset of Muscle Soreness

PubMed Central

Hatchett, Andrew; Berry, Christopher; Oliva, Claudia; Wiley, Douglas; St. Hilaire, Jacob; LaRochelle, Alex

2016-01-01

This investigation sought to examine the effect that a chocolate milk solution (CMS) and a raw milk solution (RMS) had on lower extremity induced delayed onset of muscle soreness (DOMS). Twenty trained male participants completed a set of questionnaires, prior to completing a lower extremity DOMS protocol, to determine the level of discomfort and functional limitations. Once the DOMS protocol was completed, participants were randomly assigned to either the CM or RM group. Once assigned, participants ingested 240 mL of the respective solution and completed the same set of questionnaires immediately post, 24-, 48- and 72-h post DOMS protocol. Additionally, for 10 days post-ingestion participants were contacted to learn if any negative effects were experienced as a result of ingesting either solution. Both groups reported an increase in lower extremity discomfort at each data collection interval post-DOMS protocol (post, 24-, 48- and 72-h). Participants assigned to the RM group reported high discomfort post and a relative decline in discomfort from immediately post-DOMS protocol to 72-h post. The RMS group reported substantially less discomfort at 72-h when compared to the CMS group. Ingestion of a raw milk solution immediately post strength exercise can substantially reduce the level of self-reported discomfort associated with DOMS. PMID:29910267

Competing Turing and Faraday Instabilities in Longitudinally Modulated Passive Resonators.

PubMed

Copie, François; Conforti, Matteo; Kudlinski, Alexandre; Mussot, Arnaud; Trillo, Stefano

2016-04-08

We experimentally investigate the interplay of Turing (modulational) and Faraday (parametric) instabilities in a bistable passive nonlinear resonator. The Faraday branch is induced via parametric resonance owing to a periodic modulation of the resonator dispersion. We show that the bistable switching dynamics is dramatically affected by the competition between the two instability mechanisms, which dictates two completely novel scenarios. At low detunings from resonance, switching occurs between the stable stationary lower branch and the Faraday-unstable upper branch, whereas at high detunings we observe the crossover between the Turing and Faraday periodic structures. The results are well explained in terms of the universal Lugiato-Lefever model.

NbF{sub 5} and TaF{sub 5}: Assignment of {sup 19}F NMR resonances and chemical bond analysis from GIPAW calculations

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

Biswal, Mamata, E-mail: Mamata.Biswal-Susanta_Kumar_Nayak.Etu@univ-lemans.fr; Body, Monique, E-mail: monique.body@univ-lemans.fr; Legein, Christophe, E-mail: christophe.legein@univ-lemans.fr

2013-11-15

The {sup 19}F isotropic chemical shifts (δ{sub iso}) of two isomorphic compounds, NbF{sub 5} and TaF{sub 5}, which involve six nonequivalent fluorine sites, have been experimentally determined from the reconstruction of 1D {sup 19}F MAS NMR spectra. In parallel, the corresponding {sup 19}F chemical shielding tensors have been calculated using the GIPAW method for both experimental and DFT-optimized structures. Furthermore, the [M{sub 4}F{sub 20}] units of NbF{sub 5} and TaF{sub 5} being held together by van der Waals interactions, the relevance of Grimme corrections to the DFT optimization processes has been evaluated. However, the semi-empirical dispersion correction term introduced bymore » such a method does not show any significant improvement. Nonetheless, a complete and convincing assignment of the {sup 19}F NMR lines of NbF{sub 5} and TaF{sub 5} is obtained, ensured by the linearity between experimental {sup 19}F δ{sub iso} values and calculated {sup 19}F isotropic chemical shielding σ{sub iso} values. The effects of the geometry optimizations have been carefully analyzed, confirming among other matters, the inaccuracy of the experimental structure of NbF{sub 5}. The relationships between the fluorine chemical shifts, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the length of the M–F bonds have been established. Additionally, for three of the {sup 19}F NMR lines of NbF{sub 5}, distorted multiplets, arising from {sup 1}J-coupling and residual dipolar coupling between the {sup 19}F and {sup 93}Nb nuclei, were simulated yielding to values of {sup 93}Nb–{sup 19}F {sup 1}J-coupling for the corresponding fluorine sites. - Graphical abstract: The complete assignment of the {sup 19}F NMR lines of NbF{sub 5} and TaF{sub 5} allow establishing relationships between the {sup 19}F δ{sub iso} values, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the length of the M–F bonds. Display Omitted - Highlights: • The {sup 19}F δ{sub iso} values of NbF{sub 5} and TaF{sub 5} have been determined. • The {sup 19}F chemical shielding tensors have been calculated using the GIPAW method. • A confident assignment of the {sup 19}F NMR lines of NbF{sub 5} and TaF{sub 5} is obtained. • The relationships between the {sup 19}Fδ{sub iso} values and the M–F bonds features are established.« less

A complete vibrational study on a potential environmental toxicant agent, the 3,3',4,4'-tetrachloroazobenzene combining the FTIR, FTRaman, UV-Visible and NMR spectroscopies with DFT calculations.

PubMed

Castillo, María V; Pergomet, Jorgelina L; Carnavale, Gustavo A; Davies, Lilian; Zinczuk, Juan; Brandán, Silvia A

2015-01-05

In this study 3,3',4,4'-tetrachloroazobenzene (TCAB) was prepared and then characterized by infrared, Raman, multidimensional nuclear magnetic resonance (NMR) and ultraviolet-visible spectroscopies. The density functional theory (DFT) together with the 6-31G(*) and 6-311++G(**) basis sets were used to study the structures and vibrational properties of the two cis and trans isomers of TCAB. The harmonic vibrational wavenumbers for the optimized geometries were calculated at the same theory levels. A complete assignment of all the observed bands in the vibrational spectra of TCAB was performed combining the DFT calculations with the scaled quantum mechanical force field (SQMFF) methodology. The molecular electrostatic potentials, atomic charges, bond orders and frontier orbitals for the two isomers of TCAB were compared and analyzed. The comparison of the theoretical ultraviolet-visible spectrum with the corresponding experimental demonstrates a good concordance while the calculated (1)H and (13)C chemicals shifts are in good conformity with the corresponding experimental NMR spectra of TCAB in solution. The npp(*) transitions for both forms were studied by natural bond orbital (NBO) while the topological properties were calculated by employing Bader's Atoms in the Molecules (AIM) theory. This study shows that the cis and trans isomers exhibit different structural and vibrational properties and absorption bands. Copyright © 2014. Published by Elsevier B.V.

Arthroscopic repair of massive contracted rotator cuff tears: aggressive release with anterior and posterior interval slides do not improve cuff healing and integrity.

PubMed

Kim, Sung-Jae; Kim, Sung-Hwan; Lee, Su-Keon; Seo, Jae-Wan; Chun, Yong-Min

2013-08-21

Few studies of large-to-massive contracted rotator cuff tears have examined the arthroscopic complete repair obtained by a posterior interval slide and whether the clinical outcomes or structural integrity achieved are better than those after partial repair without the posterior interval slide. The study included forty-one patients with large-to-massive contracted rotator cuff tears, not amenable to complete repair with margin convergence alone. The patients underwent either arthroscopic complete repair with a posterior interval slide and side-to-side repair of the interval slide edge (twenty-two patients; Group P) or partial repair with margin convergence (nineteen patients; Group M). The patient assignment was not randomized. The Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES) score, University of California at Los Angeles (UCLA) shoulder score, and range of motion were used to compare the functional outcomes. Preoperative and six-month postoperative magnetic resonance arthrography (MRA) images were compared within or between groups. At the two-year follow-up evaluation, the SST, ASES score, UCLA score, and range of motion had significantly improved (p < 0.001 for all) in both groups. However, no significant differences were detected between groups. Even though the difference in preoperative tear size on MRA images was not significant, follow-up MRA images identified a retear in twenty patients (91%) in Group P and a significant difference in tear size between groups (p = 0.007). The complete repair group with an aggressive release had no better clinical or structural outcomes compared with the partial repair group with margin convergence alone for large-to-massive contracted rotator cuff tears. In addition, the complete repair group had a 91% retear rate and a greater defect on follow-up MRA images. Even though this study had a relatively short-term follow-up, a complete repair of large-to-massive contracted rotator cuff tears, with an aggressive release such as posterior interval slide, may not have an increased benefit compared with partial repair without posterior interval slide.

The Impact of Implementing Web Homework in Second-Semester Calculus

ERIC Educational Resources Information Center

LaRose, P. Gavin

2010-01-01

In this study we examine the introduction of on-line homework to a Calculus II course as a replacement for ungraded pencil-and-paper homework assignments. We consider how this had an impact on students' performance in the course, on student behavior in completing the assigned work, and on student attitudes toward it. We find that students working…

A Foot in the Door: Exploring the Role of Student Teaching Assignments in Teachers' Initial Job Placements

ERIC Educational Resources Information Center

Krieg, John M.; Theobald, Roddy; Goldhaber, Dan

2016-01-01

We use data from Washington State to examine two stages of the teacher pipeline: the placement of prospective teachers into student teaching assignments and the hiring of prospective teachers into their first teaching positions. We find that prospective teachers are likely to complete their student teaching near their college and hometowns but…

Synthesis of stereospecifically deuterated desoxypodophyllotoxins and 1H-nmr assignment of desoxypodophyllotoxin

NASA Technical Reports Server (NTRS)

Pullockaran, A. J.; Kingston, D. G.; Lewis, N. G.

1989-01-01

[4 beta- 2H1]Desoxypodophyllotoxin [3], [4 alpha- 2H1]desoxypodophyllotoxin [4], and [4, 4- 2 H2]desoxypodophyllotoxin [9] were prepared from podophyllotoxin [1] via its chloride [5]. A complete assignment of the 1H-nmr spectrum of desoxypodophyllotoxin [2] was made on the basis of the spectra of the deuterated compounds [3] and [4].

The Land of Confusion? High School Students and Their Use of the World Wide Web for Research.

ERIC Educational Resources Information Center

Lorenzen, Michael

2002-01-01

Examines high school students' use of the World Wide Web to complete assignments. Findings showed the students used a good variety of resources, including libraries and the World Wide Web, to find information for assignments. However, students were weak at determining the quality of the information found on web sites. Students did poorly at…

An Ultimatum Game Approach to Billet Assignments

DTIC Science & Technology

2015-09-01

time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed , and completing and reviewing this...treatments are needed for this investigation. To conserve the subject pool and meet the budget, we elected to pursue treatments that covered salient...across billets can be partially offset through compensating wages ( hedonic wages) and/or the potential of future superior assignments. In the

Controversies of Sex Re-assignment in Genetic Males with Congenital Inadequacy of the Penis.

PubMed

Raveenthiran, Venkatachalam

2017-09-01

Sex assignment in 46XY genetic male children with congenital inadequacy of the penis (CIP) is controversial. Traditionally, children with penile length less than 2 cm at birth are considered unsuitable to be raised as males. They are typically re-assigned to female-sex and feminizing genitoplasty is usually done in infancy. However, the concept of cerebral androgen imprinting has caused paradigm shift in the philosophy of sex re-assignment. Masculinization of the brain, rather than length of the penis, is the modern criterion of sex re-assignment in CIP. This review summarizes the current understanding of the complex issue. In 46XY children with CIP, male-sex assignment appears appropriate in non-hormonal conditions such as idiopathic micropenis, aphallia and exstrophy. Female-sex re-assignment appears acceptable in complete androgen insensitivity (CAIS), while partial androgen insensitivity syndrome (PAIS) patients are highly dissatisfied with the assignment of either sex. Children with 5-alpha reductase deficiency are likely to have spontaneous penile lengthening at puberty. Hence, they are better raised as males. Although female assignment is common in pure gonadal dysgenesis, long-term results are not known to justify the decision.

Correlations of π N partial waves for multireaction analyses

DOE PAGES

Doring, M.; Revier, J.; Ronchen, D.; ...

2016-06-15

In the search for missing baryonic resonances, many analyses include data from a variety of pion- and photon-induced reactions. For elastic πN scattering, however, usually the partial waves of the SAID (Scattering Analysis Interactive Database) or other groups are fitted, instead of data. We provide the partial-wave covariance matrices needed to perform correlated χ 2 fits, in which the obtained χ 2 equals the actual χ 2 up to nonlinear and normalization corrections. For any analysis relying on partial waves extracted from elastic pion scattering, this is a prerequisite to assess the significance of resonance signals and to assign anymore » uncertainty on results. Lastly, the influence of systematic errors is also considered.« less

PONDEROSA, an automated 3D-NOESY peak picking program, enables automated protein structure determination.

PubMed

Lee, Woonghee; Kim, Jin Hae; Westler, William M; Markley, John L

2011-06-15

PONDEROSA (Peak-picking Of Noe Data Enabled by Restriction of Shift Assignments) accepts input information consisting of a protein sequence, backbone and sidechain NMR resonance assignments, and 3D-NOESY ((13)C-edited and/or (15)N-edited) spectra, and returns assignments of NOESY crosspeaks, distance and angle constraints, and a reliable NMR structure represented by a family of conformers. PONDEROSA incorporates and integrates external software packages (TALOS+, STRIDE and CYANA) to carry out different steps in the structure determination. PONDEROSA implements internal functions that identify and validate NOESY peak assignments and assess the quality of the calculated three-dimensional structure of the protein. The robustness of the analysis results from PONDEROSA's hierarchical processing steps that involve iterative interaction among the internal and external modules. PONDEROSA supports a variety of input formats: SPARKY assignment table (.shifts) and spectrum file formats (.ucsf), XEASY proton file format (.prot), and NMR-STAR format (.star). To demonstrate the utility of PONDEROSA, we used the package to determine 3D structures of two proteins: human ubiquitin and Escherichia coli iron-sulfur scaffold protein variant IscU(D39A). The automatically generated structural constraints and ensembles of conformers were as good as or better than those determined previously by much less automated means. The program, in the form of binary code along with tutorials and reference manuals, is available at http://ponderosa.nmrfam.wisc.edu/.

Superconducting pairing and the pseudogap in the nematic dynamical stripe phase of La2-xSrxCuO4

NASA Astrophysics Data System (ADS)

Sugai, S.; Takayanagi, Y.; Hayamizu, N.; Muroi, T.; Shiozaki, R.; Nohara, J.; Takenaka, K.; Okazaki, K.

2013-11-01

Fully absorption coefficient corrected Raman spectra were obtained in La2-xSrxCuO4. The B1g spectra have a Fleury-Loudon type two-magnon peak (resonant term) whose energy decreases from 3180 cm-1 (394 meV) to 440 cm-1 (55 meV) on increasing the carrier density from x = 0 to 0.25, while the B2g spectra have a 1000-3500 cm-1 (124-434 meV) hump (hill) whose lower-edge energy increases from x = 0 to 0.115 and then stays constant to x = 0.25. The B2g hump is assigned to the electronic scattering (non-resonant term) of the spectral function with magnetic self-energy. The completely different carrier density dependence arises from anisotropic magnetic excitations of spin-charge stripes. The B1g spectra were assigned to the sum of k ∥ and k⊥ stripe excitations and the B2g spectra to k⊥ stripe excitations according to the calculation by Seibold and Lorenzana (2006 Phys. Rev. B 73 144515). The k ∥ and k⊥ stripe excitations in fluctuating spin-charge stripes were separately detected for the first time. The appearance of only k⊥ stripe excitations in the electronic scattering arises from the charge hopping perpendicular to the stripe. This is the same direction as the Burgers vector of the edge dislocation in metal. The successive charge hopping in the Burgers vector direction across the charge stripes may cause Cooper pairs as predicted by Zaanen et al (2004 Ann. Phys. 310 181). Indeed, this is supported by the experimental fact that the superconducting coherent length coincides with the inter-charge stripe distance in the wide carrier density range. The one-directional charge hopping perpendicular to the stripe causes the flat Fermi surface and the pseudogap near (π,0) and (0,π), but the states around (π/2,π/2) cannot be produced. The low-energy Raman scattering disclosed that the electronic states at the Fermi arc around (π/2,π/2) are coupled to the A1g soft phonon of the tetragonal-orthorhombic phase transition. This suggests that the Fermi arc is produced by the electron-phonon interaction. All the present Raman data suggest that Cooper pairs are formed at moving edge dislocations of dynamical charge stripes.

Time-reversal symmetric resolution of unity without background integrals in open quantum systems

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

Hatano, Naomichi, E-mail: hatano@iis.u-tokyo.ac.jp; Ordonez, Gonzalo, E-mail: gordonez@butler.edu

2014-12-15

We present a new complete set of states for a class of open quantum systems, to be used in expansion of the Green’s function and the time-evolution operator. A remarkable feature of the complete set is that it observes time-reversal symmetry in the sense that it contains decaying states (resonant states) and growing states (anti-resonant states) parallelly. We can thereby pinpoint the occurrence of the breaking of time-reversal symmetry at the choice of whether we solve Schrödinger equation as an initial-condition problem or a terminal-condition problem. Another feature of the complete set is that in the subspace of the centralmore » scattering area of the system, it consists of contributions of all states with point spectra but does not contain any background integrals. In computing the time evolution, we can clearly see contribution of which point spectrum produces which time dependence. In the whole infinite state space, the complete set does contain an integral but it is over unperturbed eigenstates of the environmental area of the system and hence can be calculated analytically. We demonstrate the usefulness of the complete set by computing explicitly the survival probability and the escaping probability as well as the dynamics of wave packets. The origin of each term of matrix elements is clear in our formulation, particularly, the exponential decays due to the resonance poles.« less

Diets with High or Low Protein Content and Glycemic Index for Weight-Loss Maintenance

PubMed Central

Larsen, Thomas Meinert; Dalskov, Stine-Mathilde; van Baak, Marleen; Jebb, Susan A.; Papadaki, Angeliki; Pfeiffer, Andreas F.H.; Martinez, J. Alfredo; Handjieva-Darlenska, Teodora; Kunešová, Marie; Pihlsgård, Mats; Stender, Steen; Holst, Claus; Saris, Wim H.M.; Astrup, Arne

2012-01-01

Background Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power. Methods We enrolled overweight adults from eight European countries who had lost at least 8% of their initial body weight with a 3.3-MJ (800-kcal) low-calorie diet. Participants were randomly assigned, in a two-by-two factorial design, to one of five ad libitum diets to prevent weight regain over a 26-week period: a low-protein and low-glycemic-index diet, a low-protein and high-glycemic-index diet, a high-protein and low-glycemic-index diet, a high-protein and high-glycemic-index diet, or a control diet. Results A total of 1209 adults were screened (mean age, 41 years; body-mass index [the weight in kilograms divided by the square of the height in meters], 34), of whom 938 entered the low-calorie-diet phase of the study. A total of 773 participants who completed that phase were randomly assigned to one of the five maintenance diets; 548 completed the intervention (71%). Fewer participants in the high-protein and the low-glycemic-index groups than in the low-protein–high-glycemic-index group dropped out of the study (26.4% and 25.6%, respectively, vs. 37.4%; P = 0.02 and P = 0.01 for the respective comparisons). The mean initial weight loss with the low-calorie diet was 11.0 kg. In the analysis of participants who completed the study, only the low-protein–high-glycemic-index diet was associated with subsequent significant weight regain (1.67 kg; 95% confidence interval [CI], 0.48 to 2.87). In an intention-to-treat analysis, the weight regain was 0.93 kg less (95% CI, 0.31 to 1.55) in the groups assigned to a high-protein diet than in those assigned to a low-protein diet (P = 0.003) and 0.95 kg less (95% CI, 0.33 to 1.57) in the groups assigned to a low-glycemic-index diet than in those assigned to a high-glycemic-index diet (P = 0.003). The analysis involving participants who completed the intervention produced similar results. The groups did not differ significantly with respect to diet-related adverse events. Conclusions In this large European study, a modest increase in protein content and a modest reduction in the glycemic index led to an improvement in study completion and maintenance of weight loss. (Funded by the European Commission; ClinicalTrials.gov number, NCT00390637.) PMID:21105792

Precise ro-vibrational analysis of molecular bands forbidden in absorption: The ν8 +ν10 band of the 12C2H4 molecule

NASA Astrophysics Data System (ADS)

Ulenikov, O. N.; Gromova, O. V.; Bekhtereva, E. S.; Kashirina, N. V.; Bauerecker, S.; Horneman, V.-M.

2015-07-01

The highly accurate (experimental accuracy in line positions ∼ (1 - 2) ×10-4 cm-1) ro-vibrational spectrum of the ν8 +ν10 band of the 12C2H4 molecule was recorded for the first time with high resolution Fourier transform spectrometry and analyzed in the region of 1650-1950 cm-1 using the Hamiltonian model which takes into account Coriolis resonance interactions between the studied ν8 +ν10 band, which is forbidden in absorption, and the bands ν4 +ν8 and ν7 +ν8 . About 1570 transitions belonging to the ν8 +ν10 band were assigned in the experimental spectra with the maximum values of quantum numbers Jmax. = 35 and Kamax . = 18 . On that basis, a set of 38 vibrational, rotational, centrifugal distortion, and resonance interaction parameters was obtained from the fit. They reproduce values of 598 initial "experimental" ro-vibrational energy levels (positions of about 1570 experimentally recorded and assigned transitions) with the rms error drms = 0.00045 cm-1 (drms = 0.00028 cm-1 when upper ro-vibrational energies obtained from blended and very weak transitions were deleted from the fit).

Improved in-cell structure determination of proteins at near-physiological concentration

PubMed Central

Ikeya, Teppei; Hanashima, Tomomi; Hosoya, Saori; Shimazaki, Manato; Ikeda, Shiro; Mishima, Masaki; Güntert, Peter; Ito, Yutaka

2016-01-01

Investigating three-dimensional (3D) structures of proteins in living cells by in-cell nuclear magnetic resonance (NMR) spectroscopy opens an avenue towards understanding the structural basis of their functions and physical properties under physiological conditions inside cells. In-cell NMR provides data at atomic resolution non-invasively, and has been used to detect protein-protein interactions, thermodynamics of protein stability, the behavior of intrinsically disordered proteins, etc. in cells. However, so far only a single de novo 3D protein structure could be determined based on data derived only from in-cell NMR. Here we introduce methods that enable in-cell NMR protein structure determination for a larger number of proteins at concentrations that approach physiological ones. The new methods comprise (1) advances in the processing of non-uniformly sampled NMR data, which reduces the measurement time for the intrinsically short-lived in-cell NMR samples, (2) automatic chemical shift assignment for obtaining an optimal resonance assignment, and (3) structure refinement with Bayesian inference, which makes it possible to calculate accurate 3D protein structures from sparse data sets of conformational restraints. As an example application we determined the structure of the B1 domain of protein G at about 250 μM concentration in living E. coli cells. PMID:27910948

Anharmonic Resonances among Low-Lying Vibrational Levels of Methyl Iso-Cyanide (H_3CNC)

NASA Astrophysics Data System (ADS)

Pracna, P.; Urban, J.; Urban, V. S.; Varga, J.; Horneman, V.-M.

2010-06-01

Vibrational levels up to 1000 wn of H_3C-N≡C are currently studied in FTIR spectra together with rotational transitions within these levels. This investigation comprises the low-lying excited vibrational levels of the CNC doubly degenerate bending vibration v8=1^± 1 (267.3 wn), v8=20,± 2 (524.6 wn (A), 545.3 wn (E)), and v8=3^± 1,± 3 (792.5 wn (A1+A2), 833.9 wn (E)), respectively, and the next higher fundamental level of the C-N valence vibration v4=1 (945 wn). All these vibrational levels exhibit cubic and quartic anharmonic resonances localized to moderate values of the rotational quantum number K≤10. Therefore the system of rovibrational levels has to be treated as a global polyad in order to describe all the available data quantitatively. The ground state constants have been improved considerably by extending the assignments to higher J/K rotational states both in the purely rotational spectra recorded in the ground vibrational level and in the ground state combination differences generated from the wavenumbers assigned in the fundamental ν_4 band. Similarities and differences with respect to isoelectronic molecules CH_3CN and CH_3CCH are discussed.

1H, 15N and 13C resonance assignments of the J-domain of co-chaperone Sis1 from Saccharomyces cerevisiae.

PubMed

Pinheiro, Glaucia M S; Amorim, Gisele C; Iqbal, Anwar; Ramos, C H I; Almeida, Fabio C L

2018-04-30

Protein folding in the cell is usually aided by molecular chaperones, from which the Hsp70 (Hsp = heat shock protein) family has many important roles, such as aiding nascent folding and participating in translocation. Hsp70 has ATPase activity which is stimulated by binding to the J-domain present in co-chaperones from the Hsp40 family. Hsp40s have many functions, as for instance the binding to partially folded proteins to be delivered to Hsp70. However, the presence of the J-domain characterizes Hsp40s or, by this reason, as J-proteins. The J-domain alone can stimulate Hsp70 ATPase activity. Apparently, it also maintains the same conformation as in the whole protein although structural information on full J-proteins is still missing. This work reports the 1 H, 15 N and 13 C resonance assignments of the J-domain of a Hsp40 from Saccharomyces cerevisiae, named Sis1. Secondary structure and order parameter prediction from chemical shifts are also reported. Altogether, the data show that Sis1 J-domain is highly structured and predominantly formed by α-helices, results that are in very good agreement with those previously reported for the crystallographic structure.

Conformation, structure and molecular solvation: a spectroscopic and computational study of 2-phenoxy ethanol and its singly and multiply hydrated clusters

NASA Astrophysics Data System (ADS)

Macleod, Neil A.; Simons, John P.

2002-10-01

The conformational landscapes of 2-phenoxy ethanol (POX) and its hydrated clusters have been studied in the gas-phase, providing a model for pharmaceutical β-blockers. A combination of experimental techniques, including resonant two-photon ionisation (R2PI), laser-induced-fluorescence (LIF) and resonant ion-dip infra-red spectroscopy (RIDIRS), coupled with high-level ab initio calculations has allowed the assignment of the individually resolved spectral features to discrete conformational and supra-molecular structures. Assignments were made by comparison of experimental vibrational spectra and partially resolved ultra-violet rotational band contours with those predicted from quantum chemical calculations. The isolated molecule displays a solitary structure with an extended geometry of the side-chain which is stabilised by an intramolecular hydrogen-bond between the alcohol (proton donor) and the ether (proton acceptor) groups of the side-chain. In singly hydrated clusters the water molecule is accommodated by insertion into the intramolecular hydrogen-bond. In the doubly hydrated and higher clusters cyclic structures are generated which incorporate both the water molecules and the terminal OH group of the side-chain; additional (weak) hydrogen bonded interactions with the phenoxy group provide a degree of selectivity but essentially, the water 'droplet' forms on the end of the alcohol side-chain.

MRI and Diffusion-weighted MRI Volumetry for Identification of Complete Tumor Responders After Preoperative Chemoradiotherapy in Patients With Rectal Cancer: A Bi-institutional Validation Study.

PubMed

Lambregts, Doenja M J; Rao, Sheng-Xiang; Sassen, Sander; Martens, Milou H; Heijnen, Luc A; Buijsen, Jeroen; Sosef, Meindert; Beets, Geerard L; Vliegen, Roy A; Beets-Tan, Regina G H

2015-12-01

Retrospective single-center studies have shown that diffusion-weighted magnetic resonance imaging (DWI) is promising for identification of patients with rectal cancer with a complete tumor response after neoadjuvant chemoradiotherapy (CRT), using certain volumetric thresholds. This study aims to validate the diagnostic value of these volume thresholds in a larger, independent, and bi-institutional patient cohort. A total of 112 patients with locally advanced rectal cancer (2 centers) treated with a long course of CRT were enrolled. Patients underwent standard T2W-magnetic resonance imaging and DWI, both pre- and post-CRT. Two experienced readers independently determined pre-CRT and post-CRT tumor volumes (cm) on T2W-magnetic resonance image and diffusion-weighted magnetic resonance image by means of freehand tumor delineation. Tumor volume reduction rates (Δvolume) were calculated. Previously determined T2W and DWI threshold values for prevolume, postvolume, and Δvolume were tested to "prospectively" assess their respective diagnostic value in discriminating patients with a complete tumor response from patients with residual tumor. Twenty patients had a complete response. Using the average measurements between the 2 readers, areas under the curve for the pre-/post-/Δvolumes was 0.73/0.82/0.78 for T2W-magnetic resonance imaging and 0.77/0.92/0.86 for DWI, respectively. For T2W-volumetry, sensitivity and specificity using the predefined volume thresholds were 55% and 74% for pre-, 60% and 89% for post-, and 60% and 86% for Δvolume. For DWI volumetry, sensitivity and specificity were 65% and 76% for pre-, 70% and 98% for post-, and 70% and 93% for Δvolume. Previously established DWI volume thresholds can be reproduced with good results. Post-CRT DWI volumetry offers the best results for the detection of patients with a complete response after CRT with an area under the curve of 0.92, sensitivity of 70%, and specificity of 98%.

Re-Visiting the Electronic Energy Map of the Copper Dimer by Double-Resonant Four-Wave Mixing

NASA Astrophysics Data System (ADS)

Visser, Bradley; Bornhauser, Peter; Beck, Martin; Knopp, Gregor; Marquardt, Roberto; Gourlaouen, Christophe; van Bokhoven, Jeroen A.; Radi, Peter

2017-06-01

The copper dimer is one of the most studied transition metal (TM) diatomics due to its alkali-metal like electronic shell structure, strongly bound ground state and chemical reactivity. The high electronic promotion energy in the copper atom yields numerous low-lying electronic states compared to TM dimers with d)-hole electronic configurations. Thus, through extensive study the excited electronic structure of Cu_2 is relatively well known, however in practice few excited states have been investigated with rotational resolution or even assigned term symbols or dissociation limits. The spectroscopic methods that have been used to investigate the copper dimer until now have not possessed sufficient spectral selectivity, which has complicated the analysis of the often overlapping transitions. Resonant four-wave mixing is a non-linear absorption based spectroscopic method. In favorable cases, the two-color version (TC-RFWM) enables purely optical mass selective spectral measurements in a mixed molecular beam. Additionally, by labelling individual rotational levels in the common intermediate state the spectra are dramatically simplified. In this work, we report on the rotationally resolved characterization of low-lying electronic states of dicopper. Several term symbols have been assigned unambiguously. De-perturbation studies performed shed light on the complex electronic structure of the molecule. Furthermore, a new low-lying electronic state of Cu_2 is discovered and has important implications for the high-level theoretical structure calculations performed in parallel. In fact, the ab initio methods applied yield relative energies among the electronic levels that are almost quantitative and allow assignment of the newly observed state that is governed by spin-orbit interacting levels.

Backbone resonance assignments for G protein α(i3) subunit in the GDP-bound state.

PubMed

Mase, Yoko; Yokogawa, Mariko; Osawa, Masanori; Shimada, Ichio

2014-10-01

Guanine-nucleotide binding proteins (G proteins) serve as molecular switches in signaling pathways, by coupling the activation of G protein-coupled receptors (GPCRs) at the cell surface to intracellular responses. In the resting state, G protein forms a heterotrimer, consisting of the G protein α subunit with GDP (Gα·GDP) and the G protein βγ subunit (Gβγ). Ligand binding to GPCRs promotes the GDP-GTP exchange on Gα, leading to the dissociation of the GTP-bound form of Gα (Gα·GTP) and Gβγ. Then, Gα·GTP and Gβγ bind to their downstream effector enzymes or ion channels and regulate their activities, leading to a variety of cellular responses. Finally, Gα hydrolyzes the bound GTP to GDP and returns to the resting state by re-associating with Gβγ. The G proteins are classified with four major families based on the amino acid sequences of Gα: i/o, s, q/11, and 12/13. Here, we established the backbone resonance assignments of human Gαi3, a member of the i/o family with a molecular weight of 41 K, in complex with GDP. The chemical shifts were compared with those of Gα(i3) in complex with a GTP-analogue, GTPγS, which we recently reported, indicating that the residues with significant chemical shift differences are mostly consistent with the regions with the structural differences between the GDP- and GTPγS-bound states, as indicated in the crystal structures. The assignments of Gα(i3)·GDP would be useful for the analyses of the dynamics of Gα(i3) and its interactions with various target molecules.

Fragmentation studies of fulvic acids using collision induced dissociation fourier transform ion cyclotron resonance mass spectrometry.

PubMed

Witt, Matthias; Fuchser, Jens; Koch, Boris P

2009-04-01

The complex natural organic matter standard Suwannee river fulvic acid (SRFA) was analyzed by negative ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FTICR MS) using on-resonance collision induced dissociation (CID) of single ultrahigh resolved mass peaks in the ICR cell. Molecular formula assignment of precursor masses resulted in exactly one molecular formula for each of the peaks. Analyses of the corresponding fragment spectra and comparison to different standard substances revealed specific neutral losses and fragmentation patterns which result in structures consisting of a high degree of carboxyl- and fewer hydroxyl groups. The comparison of fragmented mass peaks within different pseudohomologous series (CH(2)-series, and CH(4) vs O exchange) suggested structurally based differences between these series. CID FTICR MS allowed isolating single mass peaks in a very complex natural organic matter spectrum. Subsequently, fragmentation gave structural insights into this material. Our results suggest that the structural diversity in complex humic substances is not as high as expected.

CW and pulsed electrically detected magnetic resonance spectroscopy at 263 GHz/12 T on operating amorphous silicon solar cells

NASA Astrophysics Data System (ADS)

Akhtar, W.; Schnegg, A.; Veber, S.; Meier, C.; Fehr, M.; Lips, K.

2015-08-01

Here we describe a new high frequency/high field continuous wave and pulsed electrically detected magnetic resonance (CW EDMR and pEDMR) setup, operating at 263 GHz and resonance fields between 0 and 12 T. Spin dependent transport in illuminated hydrogenated amorphous silicon p-i-n solar cells at 5 K and 90 K was studied by in operando 263 GHz CW and pEDMR alongside complementary X-band CW EDMR. Benefiting from the superior resolution at 263 GHz, we were able to better resolve EDMR signals originating from spin dependent hopping and recombination processes. 5 K EDMR spectra were found to be dominated by conduction and valence band tail states involved in spin dependent hopping, with additional contributions from triplet exciton states. 90 K EDMR spectra could be assigned to spin pair recombination involving conduction band tail states and dangling bonds as the dominating spin dependent transport process, with additional contributions from valence band tail and triplet exciton states.

Resonance-enhanced two-photon excitation of CaI

NASA Astrophysics Data System (ADS)

Casero-Junquera, Elena; Lawruszczuk, Rafal; Rostas, Joëlle; Taieb, Guy

1994-07-01

Induced fluorescence following visible (620-655 nm) laser excitation of the CaI radical has been detected not only in the same region (B, A-X transitions), but also in the UV (315-330 nm). The UV two-photon excitation spectrum consists of narrow bands appearing at laser frequencies located within certain bands of the Δ v = 1, 0 sequences of the B 2Σ +-X 2Σ + and A 2Π 1/2-X 2Σ + systems. The main peaks are tentatively assigned to resonance-enhanced excitation of a single vibrational level of the lowest Rydberg D 2Σ + state from successive vibrational levels of the ground state. The excitation process is a one-color two-photon optical—optical-double-resonance via B 2Σ + and A 2Π 1/2 intermediate levels. This analysis is supported by the absorption spectrum observed long ago by Walters and Barratt. The absorption and laser excitation complementary data have been used to derive approximate molecular constants for the D state.

Single-spin stochastic optical reconstruction microscopy

PubMed Central

Pfender, Matthias; Aslam, Nabeel; Waldherr, Gerald; Neumann, Philipp; Wrachtrup, Jörg

2014-01-01

We experimentally demonstrate precision addressing of single-quantum emitters by combined optical microscopy and spin resonance techniques. To this end, we use nitrogen vacancy (NV) color centers in diamond confined within a few ten nanometers as individually resolvable quantum systems. By developing a stochastic optical reconstruction microscopy (STORM) technique for NV centers, we are able to simultaneously perform sub–diffraction-limit imaging and optically detected spin resonance (ODMR) measurements on NV spins. This allows the assignment of spin resonance spectra to individual NV center locations with nanometer-scale resolution and thus further improves spatial discrimination. For example, we resolved formerly indistinguishable emitters by their spectra. Furthermore, ODMR spectra contain metrology information allowing for sub–diffraction-limit sensing of, for instance, magnetic or electric fields with inherently parallel data acquisition. As an example, we have detected nuclear spins with nanometer-scale precision. Finally, we give prospects of how this technique can evolve into a fully parallel quantum sensor for nanometer resolution imaging of delocalized quantum correlations. PMID:25267655

Fingerprinting analysis of Rhizoma chuanxiong of commercial types using 1H nuclear magnetic resonance spectroscopy and high performance liquid chromatography method.

PubMed

Qin, Hai-Lin; Deng, An-Jun; Du, Guan-Hua; Wang, Peng; Zhang, Jin-Lan; Li, Zhi-Hong

2009-06-01

The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the (1)H NMR spectra of the isolated pure compounds. The (1)H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the (1)H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the (1)H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong exhibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

A structural and spectroscopic study on carquejol, a relevant constituent of the medicinal plant Baccharis trimera (Less.) DC. (Asteraceae)

NASA Astrophysics Data System (ADS)

Minteguiaga, Manuel; Dellacassa, Eduardo; Iramain, Maximiliano A.; Catalán, César A. N.; Brandán, Silvia Antonia

2017-12-01

Carquejol and its acetate are monoterpenoids based on the rare o-menthane skeleton and distinctive components of the essential oil from Baccharis trimera. Carquejol was characterized by using Fourier Transform infrared (FT-IR) and Raman (FT-Raman), Ultraviolet-Visible (UV-Visible), Electronic Circular Dichroism (ECD), Mass, Hydrogen and Carbon Nuclear Magnetic Resonance (1H and 13C NMR) and 2D 1Hsbnd 1H gCOSY, 1Hsbnd 13CgHSQC, 1Hsbnd 13CgHMBC spectroscopies. Due to the chirality of this monoterpenoid, six different structures were analysed, of which only four showed higher populations and minimal energies. The natural bond orbital (NBO), atoms in molecules (AIM), Merz-Kollman (MK) charges, molecular electrostatic potentials (MEP) and frontier orbitals studies were performed in order to evaluate their structural, electronic, topological and vibrational properties. All calculations were performed by using the hybrid B3LYP method and the 6-31G* and 6-311++G** basis sets. The comparison of the experimental ECD spectra with the corresponding theoretical ones confirm the (4S,5R) configuration assigned to carquejol. The force fields for the most stable configurations were computed by using those two levels of theory and the complete vibrational assignments for the two conformations of carquejol are reported. The different orientations and directions of the dipole moments of the two structures and the proximity in the nucleophilic indexes with those reported for other terpenes could justify in part the potential biological properties reported for carquejol. The MEP surfaces for both structures reveal that the nucleophilic and electrophilic sites of higher reactivity are principally centred on the OH groups.

High molecular weight glucan of the culinary medicinal mushroom Agaricus bisporus is an alpha-glucan that forms complexes with low molecular weight galactan.

PubMed

Smiderle, Fhernanda R; Sassaki, Guilherme L; van Arkel, Jeroen; Iacomini, Marcello; Wichers, Harry J; Van Griensven, Leo J L D

2010-08-25

An alpha-glucan was isolated from the culinary medicinal mushroom A. bisporus by hot water extraction, ethanol precipitation and DEAE-cellulose chromatography. The resulting material showed a single HMW peak excluded from a Sephadex G50 column that could completely be degraded by alpha-amylase treatment. After heating in 1% SDS a small additional peak of low MW eluted from the G50 column. The monosaccharide composition of the main peak was evaluated by HPLC, and was found to consist of a majority of glucose (97.6%), and a minor proportion of galactose (2.4%). Methylation analysis and degradation by alpha-amylase indicated the presence of an alpha-glucan with a main chain consisting of (1(R)4)-linked units, substituted at O-6 by alpha-D-glucopyranose single-units in the relation 1:8. Mono- (13C-, 1H-NMR) and bidimensional [1H (obs.),13C-HSQC] spectroscopy analysis confirmed the alpha-configuration of the Glcp residues by low frequency resonances of C-1 at delta 100.6, 100.2, and 98.8 ppm and H-1 high field ones at delta 5.06, 5.11, and 4.74 ppm. The DEPT-13C-NMR allowed assigning the non-substituted and O-substituted -CH(2) signals at delta 60.3/60.8 and 66.2 ppm, respectively. Other assignments were attributed to C-2, C-3, C-4, C-5 and C-6 of the non-reducing ends at delta 71.8; 72.8; 70.0; 71.3 and 60.3/60.8 ppm, respectively. The minor proportion of galactose that was demonstrated was probably derived from a complex between the alpha-glucan and a low molecular weight galactan.

^1H NMR studies of the diamagnetic gallium (III) and paramagnetic iron (III) complexes of a chiral macrobicyclic ligand of bicapped tris (binaphtol) type

NASA Astrophysics Data System (ADS)

Baret, P.; Beaujolais, V.; Bougault, C.; Gaude, D.; Pierre, J.-L.

1998-01-01

^1H NMR studies of the diamagnetic gallium (III) and paramagnetic iron (III) complexes of a chiral macrobicyclic ligand of bicapped tris (binaphtol) type are described. The study of the gallium complex emphasizes: (i) that the inversion of the octahedral center is not observed and: (ii) the absence of exchange between free ligand and complex, at room temperature. In the case of the iron complex, assignments of the hyperfine shifted resolved resonances are achieved, based on temperature-behavior studies, which evidence the D3 symmetry of the complex. These assignments are in complete agreement with measured T1 values and proton-to-iron distances obtained from molecular modelling. Les complexes du gallium (III) et du fer (III) d'un ligand macrobicyclique chiral impliquant trois sous-unités de type binaphtol sont étudiés en RMN du proton en solution méthanolique. L'étude du complexe (diamagnétique) du gallium permet de montrer que le complexe : (i) ne subit pas d'inversion de la configuration (Δ/Λ) du site octaédrique et : (ii) qu'il n'y a pas d'échange entre ligand libre et complexe à la température ambiante. L'évolution du spectre du complexe paramagnétique du fer avec la température permet une attribution des protons du ligand et met en évidence la symétrie D3 du complexe. Une bonne corrélation est obtenue entre la distance fer-proton (donnée par la modélisation moléculaire) et le T1 du proton considéré.

NbF5 and TaF5: Assignment of 19F NMR resonances and chemical bond analysis from GIPAW calculations

NASA Astrophysics Data System (ADS)

Biswal, Mamata; Body, Monique; Legein, Christophe; Sadoc, Aymeric; Boucher, Florent

2013-11-01

The 19F isotropic chemical shifts (δiso) of two isomorphic compounds, NbF5 and TaF5, which involve six nonequivalent fluorine sites, have been experimentally determined from the reconstruction of 1D 19F MAS NMR spectra. In parallel, the corresponding 19F chemical shielding tensors have been calculated using the GIPAW method for both experimental and DFT-optimized structures. Furthermore, the [M4F20] units of NbF5 and TaF5 being held together by van der Waals interactions, the relevance of Grimme corrections to the DFT optimization processes has been evaluated. However, the semi-empirical dispersion correction term introduced by such a method does not show any significant improvement. Nonetheless, a complete and convincing assignment of the 19F NMR lines of NbF5 and TaF5 is obtained, ensured by the linearity between experimental 19F δiso values and calculated 19F isotropic chemical shielding σiso values. The effects of the geometry optimizations have been carefully analyzed, confirming among other matters, the inaccuracy of the experimental structure of NbF5. The relationships between the fluorine chemical shifts, the nature of the fluorine atoms (bridging or terminal), the position of the terminal ones (opposite or perpendicular to the bridging ones), the fluorine charges, the ionicity and the length of the M-F bonds have been established. Additionally, for three of the 19F NMR lines of NbF5, distorted multiplets, arising from 1J-coupling and residual dipolar coupling between the 19F and 93Nb nuclei, were simulated yielding to values of 93Nb-19F 1J-coupling for the corresponding fluorine sites.

Interictal scalp electroencephalography and intraoperative electrocorticography in magnetic resonance imaging-negative temporal lobe epilepsy surgery.

PubMed

Burkholder, David B; Sulc, Vlastimil; Hoffman, E Matthew; Cascino, Gregory D; Britton, Jeffrey W; So, Elson L; Marsh, W Richard; Meyer, Fredric B; Van Gompel, Jamie J; Giannini, Caterina; Wass, C Thomas; Watson, Robert E; Worrell, Gregory A

2014-06-01

Scalp electroencephalography (EEG) and intraoperative electrocorticography (ECoG) are routinely used in the evaluation of magnetic resonance imaging-negative temporal lobe epilepsy (TLE) undergoing standard anterior temporal lobectomy with amygdalohippocampectomy (ATL), but the utility of interictal epileptiform discharge (IED) identification and its role in outcome are poorly defined. To determine whether the following are associated with surgical outcomes in patients with magnetic resonance imaging-negative TLE who underwent standard ATL: (1) unilateral-only IEDs on preoperative scalp EEG; (2) complete resection of tissue generating IEDs on ECoG; (3) complete resection of opioid-induced IEDs recorded on ECoG; and (4) location of IEDs recorded on ECoG. Data were gathered through retrospective medical record review at a tertiary referral center. Adult and pediatric patients with TLE who underwent standard ATL between January 1, 1990, and October 15, 2010, were considered for inclusion. Inclusion criteria were magnetic resonance imaging-negative TLE, standard ECoG performed at the time of surgery, and a minimum follow-up of 12 months. Univariate analysis was performed using log-rank time-to-event analysis. Variables reaching significance with log-rank testing were further analyzed using Cox proportional hazards. Excellent or nonexcellent outcome at time of last follow-up. An excellent outcome was defined as Engel class I and a nonexcellent outcome as Engel classes II through IV. Eighty-seven patients met inclusion criteria, with 48 (55%) achieving an excellent outcome following ATL. Unilateral IEDs on scalp EEG (P = .001) and complete resection of brain regions generating IEDs on baseline intraoperative ECoG (P = .02) were associated with excellent outcomes in univariate analysis. Both were associated with excellent outcomes when analyzed with Cox proportional hazards (unilateral-only IEDs, relative risk = 0.31 [95% CI, 0.16-0.64]; complete resection of IEDs on baseline ECoG, relative risk = 0.39 [95% CI, 0.20-0.76]). Overall, 25 of 35 patients (71%) with both unilateral-only IEDs and complete resection of baseline ECoG IEDs had an excellent outcome. Unilateral-only IEDs on preoperative scalp EEG and complete resection of IEDs on baseline ECoG are associated with better outcomes following standard ATL in magnetic resonance imaging-negative TLE. Prospective evaluation is needed to clarify the use of ECoG in tailoring temporal lobectomy.

Teaching Undergraduate Students to Visualize and Communicate Public Health Data with Infographics

PubMed Central

Shanks, Justin D.; Izumi, Betty; Sun, Christina; Martin, Allea; Byker Shanks, Carmen

2017-01-01

The purpose of this study was to explore the degree to which an infographic assignment facilitated student learning around health science issues, as well as the ways in which the assignment was an effective teaching tool. The objectives of the assignment were to (1) understand the purposes of and potential uses for infographics, (2) cultivate creative visual communication skills, and (3) disseminate a complex health topic to diverse audiences. The infographic assignment was developed at Montana State University and piloted at Portland State University. Students were assigned to small groups of three or four to create an infographic focused on a health science issue. The assignment was divided into four steps: brainstorming, developing, designing, and finalizing. Focus groups were conducted to assess how learning occurred throughout the assignment and identify any opportunities for modification of the assignment. This study was conducted with freshman students enrolled at Portland State University, a public university located in downtown Portland, OR, USA. Thirty four students completed the assignment and 31 students participated in one of three focus groups. Four themes emerged from focus groups: (1) Communicating Science-Related Topics to Non-experts, (2) Developing Professional Skills, (3) Understanding Health Issues, and (4) Overall Experience. This article outlines the assignment, discusses focus group results, and presents assignment modifications. It is clear that the infographic assignment facilitated learning about accessing and translating data. This assignment is ideally suited for use with diverse college-age audiences in health education and health promotion fields. PMID:29226120

Teaching Undergraduate Students to Visualize and Communicate Public Health Data with Infographics.

PubMed

Shanks, Justin D; Izumi, Betty; Sun, Christina; Martin, Allea; Byker Shanks, Carmen

2017-01-01

The purpose of this study was to explore the degree to which an infographic assignment facilitated student learning around health science issues, as well as the ways in which the assignment was an effective teaching tool. The objectives of the assignment were to (1) understand the purposes of and potential uses for infographics, (2) cultivate creative visual communication skills, and (3) disseminate a complex health topic to diverse audiences. The infographic assignment was developed at Montana State University and piloted at Portland State University. Students were assigned to small groups of three or four to create an infographic focused on a health science issue. The assignment was divided into four steps: brainstorming, developing, designing, and finalizing. Focus groups were conducted to assess how learning occurred throughout the assignment and identify any opportunities for modification of the assignment. This study was conducted with freshman students enrolled at Portland State University, a public university located in downtown Portland, OR, USA. Thirty four students completed the assignment and 31 students participated in one of three focus groups. Four themes emerged from focus groups: (1) Communicating Science-Related Topics to Non-experts, (2) Developing Professional Skills, (3) Understanding Health Issues, and (4) Overall Experience. This article outlines the assignment, discusses focus group results, and presents assignment modifications. It is clear that the infographic assignment facilitated learning about accessing and translating data. This assignment is ideally suited for use with diverse college-age audiences in health education and health promotion fields.

Biosynthesis and NMR-studies of a double transmembrane domain from the Y4 receptor, a human GPCR.

PubMed

Zou, Chao; Naider, Fred; Zerbe, Oliver

2008-12-01

The human Y4 receptor, a class A G-protein coupled receptor (GPCR) primarily targeted by the pancreatic polypeptide (PP), is involved in a large number of physiologically important functions. This paper investigates a Y4 receptor fragment (N-TM1-TM2) comprising the N-terminal domain, the first two transmembrane (TM) helices and the first extracellular loop followed by a (His)(6) tag, and addresses synthetic problems encountered when recombinantly producing such fragments from GPCRs in Escherichia coli. Rigorous purification and usage of the optimized detergent mixture 28 mM dodecylphosphocholine (DPC)/118 mM% 1-palmitoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] (LPPG) resulted in high quality TROSY spectra indicating protein conformational homogeneity. Almost complete assignment of the backbone, including all TM residue resonances was obtained. Data on internal backbone dynamics revealed a high secondary structure content for N-TM1-TM2. Secondary chemical shifts and sequential amide proton nuclear Overhauser effects defined the TM helices. Interestingly, the properties of the N-terminal domain of this large fragment are highly similar to those determined on the isolated N-terminal domain in the presence of DPC micelles.

Peak picking NMR spectral data using non-negative matrix factorization

PubMed Central

2014-01-01

Background Simple peak-picking algorithms, such as those based on lineshape fitting, perform well when peaks are completely resolved in multidimensional NMR spectra, but often produce wrong intensities and frequencies for overlapping peak clusters. For example, NOESY-type spectra have considerable overlaps leading to significant peak-picking intensity errors, which can result in erroneous structural restraints. Precise frequencies are critical for unambiguous resonance assignments. Results To alleviate this problem, a more sophisticated peaks decomposition algorithm, based on non-negative matrix factorization (NMF), was developed. We produce peak shapes from Fourier-transformed NMR spectra. Apart from its main goal of deriving components from spectra and producing peak lists automatically, the NMF approach can also be applied if the positions of some peaks are known a priori, e.g. from consistently referenced spectral dimensions of other experiments. Conclusions Application of the NMF algorithm to a three-dimensional peak list of the 23 kDa bi-domain section of the RcsD protein (RcsD-ABL-HPt, residues 688-890) as well as to synthetic HSQC data shows that peaks can be picked accurately also in spectral regions with strong overlap. PMID:24511909

Chalcogen analogues of nicotine lactam studied by NMR, FTIR, DFT and X-ray methods

NASA Astrophysics Data System (ADS)

Jasiewicz, Beata; Malczewska-Jaskóła, Karolina; Kowalczyk, Iwona; Warżajtis, Beata; Rychlewska, Urszula

2014-07-01

The selenoanalogue of nicotine has been synthesized and characterized by spectroscopic and X-ray diffraction methods. The crystals of selenonicotine are isomorphic with the thionicotine homologue and consist of molecules engaged in columnar π⋯π stacking interactions between antiparallely arranged pyridine moieties. These interactions, absent in other crystals containing nicotine fragments, seem to be induced by the presence of a lactam group. The molecular structures in the vacuum of the oxo-, thio- and selenonicotine homologues have been calculated by the DFT method and compared with the available X-ray data. The delocalized structure of thionicotine is stabilized by intramolecular Csbnd H⋯S hydrogen bond, which becomes weaker in the partial zwitterionic resonance structure of selenonicotine in favor of multiple Csbnd H⋯Se intermolecular hydrogen-bonds. The calculated data allow a complete assignment of vibration modes in the solid state FTIR spectra. The 1H and 13C NMR chemical shifts were calculated by the GIAO method with B3LYP/6-311G(3df) level. A comparison between experimental and calculated theoretical results indicates that the density functional B3LYP method provided satisfactory results for predicting FTIR, 1H, 13C NMR spectra properties.

Structural, antimicrobial and computational characterization of 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea.

PubMed

Atiş, Murat; Karipcin, Fatma; Sarıboğa, Bahtiyar; Taş, Murat; Çelik, Hasan

2012-12-01

A new thiourea derivative, 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea (bcht) has been synthesized from the reaction of 2-amino-4-chlorophenol with benzoyl isothiocyanate. The title compound has been characterized by elemental analyses, FT-IR, (13)C, (1)H NMR spectroscopy and the single crystal X-ray diffraction analysis. The structure of bcht derived from X-ray diffraction of a single crystal has been presented. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method using 6-311++G(d,p) basis set. The complete assignments of all vibrational modes were performed on the basis of the total energy distributions (TED). Isotropic chemical shifts ((13)C NMR and (1)H NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. Theoretical calculations of bond parameters, harmonic vibration frequencies and nuclear magnetic resonance are in good agreement with experimental results. The UV absorption spectra of the compound that dissolved in ACN and MeOH were recorded. Bcht was also screened for antimicrobial activity against pathogenic bacteria and fungi. Copyright © 2012 Elsevier B.V. All rights reserved.

Theoretical investigation on the molecular structure, Infrared, Raman and NMR spectra of para-halogen benzenesulfonamides, 4-X-C 6H 4SO 2NH 2 (X = Cl, Br or F)

NASA Astrophysics Data System (ADS)

Karabacak, Mehmet; Çınar, Mehmet; Çoruh, Ali; Kurt, Mustafa

2009-02-01

In the present study, the structural properties of para-halogen benzenesulfonamides, 4-XC 6H 4SO 2NH 2 (4-chlorobenzenesulfonamide (I), 4-bromobenzenesulfonamide (II) and 4-fluorobenzenesulfonamide (III)) have been studied extensively utilizing ab initio Hartree-Fock (HF) and density functional theory (DFT) employing B3LYP exchange correlation. The vibrational frequencies were calculated and scaled values were compared with experimental values. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The effects of the halogen substituent on the characteristic benzenesulfonamides bands in the spectra are discussed. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecules were calculated using the Gauge-Invariant Atomic Orbital (GIAO) method. Finally, geometric parameters, vibrational bands and chemical shifts were compared with available experimental data of the molecules. The fully optimized geometries of the molecules were found to be consistent with the X-ray crystal structures. The observed and calculated frequencies and chemical shifts were found to be in very good agreement.

Gender assignment in patients with disorder of sex development.

PubMed

Mendonca, Berenice B

2014-12-01

To examine the sex assignment in patients with atypical external genitalia, a particularly challenging situation, especially when the genital appearance is not compatible with the sex chromosome. The most important factors that influence sex assignment include the definite diagnosis, genital appearance, surgical options, potential for fertility, risks of gonadal malignancy and, finally, the perception of the patients and their parents. Full disclosure and complete involvement of the parents in making decisions concerning gender assignment and/or genital surgery must be part of the basic medical care for children with disorder of sex development. Patients with disorder of sex development should receive long-term care provided by multidisciplinary teams in centers of excellence with ample experience in the management of this disorder.

Learning Bridge Tool to Improve Student Learning, Preceptor Training, and Faculty Teamwork

PubMed Central

Cawley, Pauline; Arendt, Cassandra S.

2011-01-01

Objectives To implement a Learning Bridge tool to improve educational outcomes for pharmacy students as well as for preceptors and faculty members. Design Pharmacy faculty members collaborated to write 9 case-based assignments that first-year pharmacy (P1) students worked with preceptors to complete while at experiential sites. Assessment Students, faculty members, and preceptors were surveyed about their perceptions of the Learning Bridge process. As in our pilot study,1 the Learning Bridge process promoted student learning. Additionally, the Learning Bridge assignments familiarized preceptors with the school's P1 curriculum and its content. Faculty teamwork also was increased through collaborating on the assignments. Conclusions The Learning Bridge assignments provided a compelling learning environment and benefited students, preceptors, and faculty members. PMID:21655400

A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing.

PubMed

Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian

2015-10-23

The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m < n), such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP) complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation.

Learning bridge tool to improve student learning, preceptor training, and faculty teamwork.

PubMed

Karimi, Reza; Cawley, Pauline; Arendt, Cassandra S

2011-04-11

To implement a Learning Bridge tool to improve educational outcomes for pharmacy students as well as for preceptors and faculty members. Pharmacy faculty members collaborated to write 9 case-based assignments that first-year pharmacy (P1) students worked with preceptors to complete while at experiential sites. Students, faculty members, and preceptors were surveyed about their perceptions of the Learning Bridge process. As in our pilot study,(1) the Learning Bridge process promoted student learning. Additionally, the Learning Bridge assignments familiarized preceptors with the school's P1 curriculum and its content. Faculty teamwork also was increased through collaborating on the assignments. The Learning Bridge assignments provided a compelling learning environment and benefited students, preceptors, and faculty members.

Critical Thinking and Reflection Exercises in a Biochemistry Course to Improve Prospective Health Professions Students’ Attitudes Toward Physician-Pharmacist Collaboration

PubMed Central

Cornell, Susan; Fjortoft, Nancy; Bjork, Bryan C.; Chandar, Nalini; Green, Jacalyn M.; La Salle, Sophie; Viselli, Susan M.; Burdick, Paulette; Lynch, Sean M.

2013-01-01

Objective. To determine the impact of performing critical-thinking and reflection assignments within interdisciplinary learning teams in a biochemistry course on pharmacy students’ and prospective health professions students’ collaboration scores. Design. Pharmacy students and prospective medical, dental, and other health professions students enrolled in a sequence of 2 required biochemistry courses. They were randomly assigned to interdisciplinary learning teams in which they were required to complete case assignments, thinking and reflection exercises, and a team service-learning project. Assessment. Students were asked to complete the Scale of Attitudes Toward Physician-Pharmacist Collaboration prior to the first course, following the first course, and following the second course. The physician-pharmacist collaboration scores of prospective health professions students increased significantly (p<0.001). Conclusions. Having prospective health professions students work in teams with pharmacy students to think and reflect in and outside the classroom improves their attitudes toward physician-pharmacist collaboration. PMID:24159210

Group cognitive behavioural therapy for depression outcomes predicted by willingness to engage in homework, compliance with homework, and cognitive restructuring skill acquisition.

PubMed

Neimeyer, Robert A; Kazantzis, Nikolaos; Kassler, Dina M; Baker, Kurt D; Fletcher, Richard

2008-01-01

There is a need to understand the mechanism through which homework contributes to clinically meaningful change in therapy. Theoretically meaningful factors such as willingness to complete therapeutic assignments and cognitive skill acquisition have not been carefully studied in prior research. Depressed outpatients (N = 46) received cognitive behavioural group therapy for a 10-week period and were assigned relevant homework activities. Patient self-report and independent ratings of homework compliance were obtained on a session-by-session basis. Using path analysis, the authors found evidence that willingness to complete homework assignments and mastery of skill in cognitive restructuring helped account for the relationship between homework compliance and reduced symptom severity (R2 = .40). However, paths were only significant when patient self-report of homework compliance was used in the model. The present study highlights the problems in assessing homework compliance and in assuming that independent assessment of compliance is more accurate than patient self-report.

Charmonium resonances in the 3.9 GeV/c2 energy region and the X(3915)/X(3930) puzzle

NASA Astrophysics Data System (ADS)

Ortega, Pablo G.; Segovia, Jorge; Entem, David R.; Fernández, Francisco

2018-03-01

An interesting controversy has emerged challenging the widely accepted nature of the X (3915) and the X (3930) resonances, which had initially been assigned to the χc0 (2 P) and χc2 (2 P) c c bar states, respectively. To unveil their inner structure, the properties of the JPC =0++ and JPC =2++ charmonium states in the energy region of these resonances are analyzed in the framework of a constituent quark model. Together with the bare q q bar states, threshold effects due to the opening of nearby meson-meson channels are included in a coupled-channels scheme calculation. We find that the structure of both states is dominantly molecular with a probability of bare q q bar states lower than 45%. Our results favor the hypothesis that X (3915) and X (3930) resonances arise as different decay mechanisms of the same JPC =2++ state. Moreover we find an explanation for the recently discovered M = 3860MeV /c2 as a JPC =0++ 2P state and rediscover the lost Y (3940) as an additional state in the JPC =0++ family.

Examination of gamma-irradiated fruits and vegetables by electron spin resonance spectroscopy

NASA Astrophysics Data System (ADS)

Desrosiers, Marc F.; McLaughlin, William L.

The ESR spectra of the seeds, pits, shells, and skins of a variety of irradiated fruits and vegetables were measured. All spectra, control and irradiated, contained a single resonance with a g-factor of 2.00. Additional resonances due to Mn 2+ were observed for the drupelets of blackberries and red raspberries. An unusual radiation-induced radical was observed for irradiated mango seed; however, the signal decayed completely within a few days. It was concluded that only in a few specialized cases could the ESR resonances observed be suitable for postirradiation monitoring or dosimetry.

A Foot in the Door: Exploring the Role of Student Teaching Assignments in Teachers' Initial Job Placements. CEDR Working Paper. WP #2015-2.1

ERIC Educational Resources Information Center

Krieg, John; Theobald, Roddy; Goldhaber, Dan

2015-01-01

We use data from Washington State to examine two distinct stages of the teacher pipeline: the placement of prospective teachers in student teaching assignments; and the hiring of prospective teachers into their first teaching positions. We find that prospective teachers are likely to complete their student teaching near their college and…

How to Create a Student-Generated Database, in a Large Nutrition Class, to Illustrate the Analysis of Nutrient and Food Intakes

ERIC Educational Resources Information Center

Gurfinkel, Debbie M.; Wolever, Thomas M. S.

2017-01-01

The completion of a 3-d food record, using commonly available nutrient analysis software, is a typical assignment for students in nutrition and food science programs. While these assignments help students evaluate their personal diets, it is insufficient to teach students about surveys of large population cohorts. This paper shows how the Test,…

A complete 1H and 13C NMR data assignment for the diterpene methyl (-)-zanzibarate by 2D spectroscopy and NOE experiments.

PubMed

Imamura, P M; Miranda, P C M L; Giacomini, R A

2004-06-01

The 1H and 13C NMR spectra of methyl (-)-zanzibarate (1), an ent-labdanic diterpene isolated from the epicarp of Hymenaea courbaril var. altissima (Leguminosaea, Cesalpinoideae, Detariae), was fully assigned by COSY experiments, 13C/1H shift correlation diagrams and NOE experiments. Copyright 2004 John Wiley & Sons, Ltd.

Role of spontaneous emission through operating transition in probe-field spectroscopy of two-level systems

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

Saprykin, E. G.; Chernenko, A. A., E-mail: chernen@isp.nsc.ru; Shalagin, A. M.

Analytical and numerical investigations are carried out of the effect of spontaneous decay through operating transition on the shape of a resonance in the work of a probe field under a strong field applied to the transition. A narrow nonlinear resonance arising on transitions with long-living lower level in the work of a probe field can manifest itself in the form of a traditional minimum and a peak as a function of the first Einstein coefficient for the operating transition. The transformation of the resonance from a minimum to a peak is attributed to the specific character of relaxation ofmore » lower-level population beatings on a closed or almost closed transition (the decay of the upper level occurs completely or almost completely through the operating transition).« less

Two-dimensional sup 1 H nuclear magnetic resonance study of AaH IT, an anti-insect toxin from the scorpion Androctonus australis Hector. Sequential resonance assignments and folding of the polypeptide chain

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

Darbon, H.; Weber, C.; Braun, W.

1991-02-19

Sequence-specific nuclear magnetic resonance assignments for the polypeptide backbone and for most of the amino acid side-chain protons, as well as the general folding of AaH IT, are described. AaH IT is a neurotoxin purified from the venom of the scorpion Androctonus australis Hector and is specifically active on the insect nervous system. The secondary structure and the hydrogen-bonding patterns in the regular secondary structure elements are deduced from nuclear Overhauser effects and the sequence locations of the slowly exchanging amide protons. The backbone folding is determined by distance geometry calculations with the DISMAN program. The regular secondary structure includesmore » two and a half turns of {alpha}-helix running from residues 21 to 30 and a three-stranded antiparallel {beta}-sheet including peptides 3-5, 34-38, and 41-46. Two tight turns are present, one connecting the end of the {alpha}-helix to an external strand of the {beta}-sheet, i.e., turn 31-34, and another connecting this same strand to the central one, i.e., turn 38-41. The differences in the specificity of these related proteins, which are able to discriminate between mammalian and insect voltage-dependent sodium channels of excitable tissues, are most probably brought about by the position of the C-terminal peptide with regard to a hydrophobic surface common to all scorpion toxins examined thus far. Thus, the interaction of a given scorpion toxin with its receptor might well be governed by the presence of this solvent-exposed hydrophobic surface, whereas adjacent areas modulate the specificity of the interaction.« less

Amino Acid Selective 13C Labeling and 13C Scrambling Profile Analysis of Protein α and Side-Chain Carbons in Escherichia coli Utilized for Protein Nuclear Magnetic Resonance.

PubMed

Sugiki, Toshihiko; Furuita, Kyoko; Fujiwara, Toshimichi; Kojima, Chojiro

2018-06-20

Amino acid selective isotope labeling is an important nuclear magnetic resonance technique, especially for larger proteins, providing strong bases for the unambiguous resonance assignments and information concerning the structure, dynamics, and intermolecular interactions. Amino acid selective 15 N labeling suffers from isotope dilution caused by metabolic interconversion of the amino acids, resulting in isotope scrambling within the target protein. Carbonyl 13 C atoms experience less isotope scrambling than the main-chain 15 N atoms do. However, little is known about the side-chain 13 C atoms. Here, the 13 C scrambling profiles of the Cα and side-chain carbons were investigated for 15 N scrambling-prone amino acids, such as Leu, Ile, Tyr, Phe, Thr, Val, and Ala. The level of isotope scrambling was substantially lower in 13 Cα and 13 C side-chain labeling than in 15 N labeling. We utilized this reduced scrambling-prone character of 13 C as a simple and efficient method for amino acid selective 13 C labeling using an Escherichia coli cold-shock expression system and high-cell density fermentation. Using this method, the 13 C labeling efficiency was >80% for Leu and Ile, ∼60% for Tyr and Phe, ∼50% for Thr, ∼40% for Val, and 30-40% for Ala. 1 H- 15 N heteronuclear single-quantum coherence signals of the 15 N scrambling-prone amino acid were also easily filtered using 15 N-{ 13 Cα} spin-echo difference experiments. Our method could be applied to the assignment of the 55 kDa protein.

NMR backbone assignments of the tyrosine kinase domain of human fibroblast growth factor receptor 3 in apo state and in complex with inhibitor PD173074.

PubMed

Sanfelice, Domenico; Koss, Hans; Bunney, Tom D; Thompson, Gary S; Farrell, Brendan; Katan, Matilda; Breeze, Alexander L

2018-03-26

Fibroblast growth factors receptors (FGFR) are transmembrane protein tyrosine kinases involved in many cellular process, including growth, differentiation and angiogenesis. Dysregulation of FGFR enzymatic activity is associated with developmental disorders and cancers; therefore FGFRs have become attractive targets for drug discovery, with a number of agents in late-stage clinical trials. Here, we present the backbone resonance assignments of FGFR3 tyrosine kinase domain in the ligand-free form and in complex with the canonical FGFR kinase inhibitor PD173074. Analysis of chemical shift changes upon inhibitor binding highlights a characteristic pattern of allosteric network perturbations that is of relevance for future drug discovery activities aimed at development of conformationally-selective FGFR inhibitors.

Coherent versus incoherent resonant emission: an experimental method for easy discrimination and measurement

NASA Astrophysics Data System (ADS)

Ceccherini, S.; Colocci, M.; Gurioli, M.; Bogani, F.

1998-11-01

The distinction between the coherent and the incoherent component of the radiation emitted from resonantly excited material systems is difficult experimentally, particularly when ultra-short optical pulses are used for excitation. We propose an experimental procedure allowing an easy measurement of the two components. The method is completely general and applicable to any kind of physical system; its feasibility is demonstrated on the resonant emission from excitons in a semiconductor quantum well.

A simple method for astigmatic compensation of folded resonator without Brewster window.

PubMed

Qiao, Wen; Xiaojun, Zhang; Yonggang, Wang; Liqun, Sun; Hanben, Niu

2014-02-10

A folded resonator requires an oblique angle of incidence on the folded curved mirror, which introduces astigmatic distortions that limit the performance of the lasers. We present a simple method to compensate the astigmatism of folded resonator without Brewster windows for the first time to the best of our knowledge. Based on the theory of the propagation and transformation of Gaussian beams, the method is both effective and reliable. Theoretical results show that the folded resonator can be compensated astigmatism completely when the following two conditions are fulfilled. Firstly, when the Gaussian beam with a determined size beam waist is obliquely incident on an off-axis concave mirror, two new Gaussian beam respectively in the tangential and sagittal planes are formed. Another off-axis concave mirror is located at another intersection point of the two new Gaussian beams. Secondly, adjusting the incident angle of the second concave mirror or its focal length can make the above two Gaussian beam coincide in the image plane of the second concave mirror, which compensates the astigmatic aberration completely. A side-pumped continues-wave (CW) passively mode locked Nd:YAG laser was taken as an example of the astigmatically compensated folded resonators. The experimental results show good agreement with the theoretical predictions. This method can be used effectively to design astigmatically compensated cavities resonator of high-performance lasers.

Do monkeys choose to choose?

PubMed

Perdue, Bonnie M; Evans, Theodore A; Washburn, David A; Rumbaugh, Duane M; Beran, Michael J

2014-06-01

Both empirical and anecdotal evidence supports the idea that choice is preferred by humans. Previous research has demonstrated that this preference extends to nonhuman animals, but it remains largely unknown whether animals will actively seek out or prefer opportunities to choose. Here we explored the issue of whether capuchin and rhesus monkeys choose to choose. We used a modified version of the SELECT task-a computer program in which monkeys can choose the order of completion of various psychomotor and cognitive tasks. In the present experiments, each trial began with a choice between two icons, one of which allowed the monkey to select the order of task completion, and the other of which led to the assignment of a task order by the computer. In either case, subjects still had to complete the same number of tasks and the same number of task trials. The tasks were relatively easy, and the monkeys responded correctly on most trials. Thus, global reinforcement rates were approximately equated across conditions. The only difference was whether the monkey chose the task order or it was assigned, thus isolating the act of choosing. Given sufficient experience with the task icons, all monkeys showed a significant preference for choice when the alternative was a randomly assigned order of tasks. To a lesser extent, some of the monkeys maintained a preference for choice over a preferred, but computer-assigned, task order that was yoked to their own previous choice selection. The results indicated that monkeys prefer to choose when all other aspects of the task are equated.

Optically detected magnetic resonance studies on pi-conjugated polymers and novel carbon allotropes

NASA Astrophysics Data System (ADS)

Partee, Jonathan Farel

1997-12-01

The photophysics of poly(p-phenylene)-type ladder polymers (m-LPPP) and 2,5-dibutoxy poly(p-phenylene ethynylene) (DBO-PPE) films and solutions were studied by X-band photoluminescence detected magnetic resonance (PLDMR). Frequency resolved PLDMR measurements on LPPP, DBO-PPE, poly(3-hexylthiophene) (P3HT), poly(p-phenylene-vinylene) (PPV), and Csb{70} are also reported and discussed. All the polymer samples exhibit three distinct features when excited at wavelengths lambda≥ 458nm: (i) A narrow PL-enhancing spin-1/2 polaron resonance, (ii) broad full- and (iii) half-field spin-1 triplet exciton powder patterns due to the Deltamsbs = 1 and Deltamsbs = 2 transitions among the triplet sublevels, respectively. The full-width at half maximum (FWHM) of the spin-1/2 resonance in LPPP decreased from film to solution. However, the FWHM of that resonance in PPE was identical at all concentrations. This spin-1/2 resonance is assigned to the magnetic resonance enhancement of the recombination of both interchain and intrachain-intersegment polaron pairs which quench singlet exciton recombination. In solid m-LPPP samples, the aggregate PL gives rise to a proportionally higher magnetic resonance effect than other parts of the PL spectrum. In DBO-PPE and m-LPPP solutions, the triplet resonance decreased with decreasing concentration. This suggests that the triplet state is an intrinsic long-lived (˜30mus) trapped state localized on a phenylene ring and stabilized by coupling to a unit of an adjacent chain. Frequency resolved measurements of the lifetime of the species affected by the resonance conditions for all the polymers are described and discussed. The lifetimes appeared to include: (i) fast (9mus ≤ tausb1 ≤ 40mus) and (ii) slow (575mus\\ ≤ tausb2≤ 1868mus) components. The lifetimes increased with increasing concentration of the polymers in toluene solutions. These results can be interpreted to provide support for the interchain/intersegment polaron model or a distribution of lifetimes model.

Developing Responsibility for Completing and Handing in Daily Homework Assignments for Students in Grades Three, Four, and Five.

ERIC Educational Resources Information Center

Shepard, Joan M.

This practicum was designed to increase responsibility for completing and handing in homework among students in grades three, four, and five in a mid-Atlantic school district. Of a total of 128 students in these grades, 28 were identified to learn strategies to aid in completing homework. Nine solution strategies were employed: (1) provide…

Experimental Evidence on the Effect of Childhood Investments on Postsecondary Attainment and Degree Completion. NBER Working Paper No. 17533

ERIC Educational Resources Information Center

Dynarski, Susan; Hyman, Joshua M.; Schanzenbach, Diane Whitmore

2011-01-01

This paper examines the effect of early childhood investments on college enrollment and degree completion. We use the random assignment in the Project STAR experiment to estimate the effect of smaller classes in primary school on college entry, college choice, and degree completion. We improve on existing work in this area with unusually detailed…

34 CFR 686.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

...): (1) One complete school year, or two complete and consecutive half-years from different school years... full-time employment as a teacher. For an individual teaching in more than one school, the... performance for tests and assignments yielded a numeric equivalent of a 3.25 GPA on a 4.0 scale; and (ii) For...

34 CFR 686.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

...): (1) One complete school year, or two complete and consecutive half-years from different school years... full-time employment as a teacher. For an individual teaching in more than one school, the... performance for tests and assignments yielded a numeric equivalent of a 3.25 GPA on a 4.0 scale; and (ii) For...

34 CFR 686.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) One complete school year, or two complete and consecutive half-years from different school years... full-time employment as a teacher. For an individual teaching in more than one school, the... performance for tests and assignments yielded a numeric equivalent of a 3.25 GPA on a 4.0 scale; and (ii) For...

34 CFR 686.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

...): (1) One complete school year, or two complete and consecutive half-years from different school years... full-time employment as a teacher. For an individual teaching in more than one school, the... performance for tests and assignments yielded a numeric equivalent of a 3.25 GPA on a 4.0 scale; and (ii) For...

34 CFR 686.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

...): (1) One complete school year, or two complete and consecutive half-years from different school years... full-time employment as a teacher. For an individual teaching in more than one school, the... performance for tests and assignments yielded a numeric equivalent of a 3.25 GPA on a 4.0 scale; and (ii) For...

Positive and Negative Consequences in Contingency Contracts: Their Relative Effectiveness on Arithmetic Performance.

ERIC Educational Resources Information Center

Kidd, Teresa A.; Saudargas, Richard A.

1988-01-01

The study with two elementary students who had low levels of completion and accuracy on daily arithmetic assignments found that a negative consequence was not necessary and that use of a positive component alone was sufficient to maintain high levels of completion and accuracy. (Author/DB)

Homework Hotlines: Recommendations for Successful Practice

ERIC Educational Resources Information Center

Reach, Kelle; Cooper, Harris

2004-01-01

It is common for students to have difficulty completing homework in a timely and accurate manner. Many school districts and organizations offer homework hotlines to help students complete assignments. However, educators lack a clear description of what is necessary to establish and maintain an effective hotline. This article addresses four issues…

Analysis of labor employment assessment on production machine to minimize time production

NASA Astrophysics Data System (ADS)

Hernawati, Tri; Suliawati; Sari Gumay, Vita

2018-03-01

Every company both in the field of service and manufacturing always trying to pass efficiency of it’s resource use. One resource that has an important role is labor. Labor has different efficiency levels for different jobs anyway. Problems related to the optimal allocation of labor that has different levels of efficiency for different jobs are called assignment problems, which is a special case of linear programming. In this research, Analysis of Labor Employment Assesment on Production Machine to Minimize Time Production, in PT PDM is done by using Hungarian algorithm. The aim of the research is to get the assignment of optimal labor on production machine to minimize time production. The results showed that the assignment of existing labor is not suitable because the time of completion of the assignment is longer than the assignment by using the Hungarian algorithm. By applying the Hungarian algorithm obtained time savings of 16%.

Learning through loss: implementing lossography narratives in death education.

PubMed

Bolkan, Cory; Srinivasan, Erica; Dewar, Alexis R; Schubel, Stacey

2015-01-01

Students may have a greater willingness to discuss issues of death and loss through written assignments; however, there is little guidance for instructors regarding how to manage these sensitive assignments, nor how students benefit from them. The authors implemented and evaluated a "lossography" assignment in an undergraduate thanatology course in which students wrote about their losses and anonymously shared these narratives with their classmates. Although many themes of loss emerged, the most frequently reported significant loss was death of a grandparent. Additionally, most significant losses occurred in childhood/adolescence. Prominent themes related to student learning included gaining self-awareness, knowledge about grief responses, and compassion for others. Students (N = 64) also completed a survey reflecting on their course learning. Of all aspects of course delivery, 44% identified the lossography as the most beneficial, whereas 97% recommended this assignment for future students. The implications of the assignment for death education are also discussed.

Student-peer mentoring on a drug information response.

PubMed

Rodis, Jennifer Lin; Backo, Jennifer; Schmidt, Brittany M; Pruchnicki, Maria C

2014-03-12

To implement a student peer-mentoring program with a drug information response assignment in an introductory pharmacy practice course. Second-year student pharmacists (P2 mentors) enrolled in an independent study course were randomly assigned first-year student pharmacists (P1 mentees) to mentor on a drug information assignment. The P2 mentors provided feedback to P1 mentees' assignment drafts. The P1 mentees had the opportunity to revise the draft prior to turning in the completed assignment to course faculty members for grading. Both P1 mentees and P2 mentors agreed the mentorship improved their ability to prepare a drug information response (76% and 100%, respectively). A majority of the student pharmacists would choose to be involved in the program again. The student peer-mentoring program was successful in improving student pharmacists' perceptions of ability to compose a drug information response.

Calibrated peer review assignments for the earth sciences

USGS Publications Warehouse

Rudd, J.A.; Wang, V.Z.; Cervato, C.; Ridky, R.W.

2009-01-01

Calibrated Peer Review ??? (CPR), a web-based instructional tool developed as part of the National Science Foundation reform initiatives in undergraduate science education, allows instructors to incorporate multiple writing assignments in large courses without overwhelming the instructor. This study reports successful implementation of CPR in a large, introductory geology course and student learning of geoscience content. For each CPR assignment in this study, students studied web-based and paper resources, wrote an essay, and reviewed seven essays (three from the instructor, three from peers, and their own) on the topic. Although many students expressed negative attitudes and concerns, particularly about the peer review process of this innovative instructional approach, they also recognized the learning potential of completing CPR assignments. Comparing instruction on earthquakes and plate boundaries using a CPR assignment vs. an instructional video lecture and homework essay with extensive instructor feedback, students mastered more content via CPR instruction.

Improvement of medication event interventions through use of an electronic database.

PubMed

Merandi, Jenna; Morvay, Shelly; Lewe, Dorcas; Stewart, Barb; Catt, Char; Chanthasene, Phillip P; McClead, Richard; Kappeler, Karl; Mirtallo, Jay M

2013-10-01

Patient safety enhancements achieved through the use of an electronic Web-based system for responding to adverse drug events (ADEs) are described. A two-phase initiative was carried out at an academic pediatric hospital to improve processes related to "medication event huddles" (interdisciplinary meetings focused on ADE interventions). Phase 1 of the initiative entailed a review of huddles and interventions over a 16-month baseline period during which multiple databases were used to manage the huddle process and staff interventions were assigned via manually generated e-mail reminders. Phase 1 data collection included ADE details (e.g., medications and staff involved, location and date of event) and the types and frequencies of interventions. Based on the phase 1 analysis, an electronic database was created to eliminate the use of multiple systems for huddle scheduling and documentation and to automatically generate e-mail reminders on assigned interventions. In phase 2 of the initiative, the impact of the database during a 5-month period was evaluated; the primary outcome was the percentage of interventions documented as completed after database implementation. During the postimplementation period, 44.7% of assigned interventions were completed, compared with a completion rate of 21% during the preimplementation period, and interventions documented as incomplete decreased from 77% to 43.7% (p < 0.0001). Process changes, education, and medication order improvements were the most frequently documented categories of interventions. Implementation of a user-friendly electronic database improved intervention completion and documentation after medication event huddles.

Assessment of the trauma evaluation and management (TEAM) module in Australia.

PubMed

Ali, Jameel; Danne, Peter; McColl, Geoff

2004-08-01

To assess the immediate effect on trauma-related knowledge of the trauma evaluation and management (TEAM) program applied to medical students in Australia. 73 final year medical students from Melbourne were randomly assigned to two experimental groups (E1 and E2 who completed the TEAM program after a 20 item MCQ pre-test on trauma resuscitation and a second MCQ exam after the TEAM program) and two control groups (C1 and C2 who completed the pre- and post-MCQ exams before completing the TEAM module). All 73 students completed an evaluation questionnaire. Paired and unpaired t-tests were used for within and between groups comparisons. Groups C1 and C2 had similar mean scores in pre- and post-tests ranging from 57.2 to 60.5%. Groups E1 and E2 had similar pre-test scores but increased their post-test scores (pre-test range 53.8-57.1% and post-test 68.8-77.4%, P < 0.05). On a scale of 1-5 with five being the highest, a score of four or greater was assigned by over 74% of the students that the objectives were met, over 80% that trauma knowledge was improved, 25-40% that clinical skills were improved with over 74% overall satisfaction. Over 75% assigned a score of four or greater suggesting the module be mandatory. After the TEAM program there was significant improvement in cognitive skills. The students strongly supported its introduction in the undergraduate curriculum.

Classifying with confidence from incomplete information.

DOE PAGES

Parrish, Nathan; Anderson, Hyrum S.; Gupta, Maya R.; ...

2013-12-01

For this paper, we consider the problem of classifying a test sample given incomplete information. This problem arises naturally when data about a test sample is collected over time, or when costs must be incurred to compute the classification features. For example, in a distributed sensor network only a fraction of the sensors may have reported measurements at a certain time, and additional time, power, and bandwidth is needed to collect the complete data to classify. A practical goal is to assign a class label as soon as enough data is available to make a good decision. We formalize thismore » goal through the notion of reliability—the probability that a label assigned given incomplete data would be the same as the label assigned given the complete data, and we propose a method to classify incomplete data only if some reliability threshold is met. Our approach models the complete data as a random variable whose distribution is dependent on the current incomplete data and the (complete) training data. The method differs from standard imputation strategies in that our focus is on determining the reliability of the classification decision, rather than just the class label. We show that the method provides useful reliability estimates of the correctness of the imputed class labels on a set of experiments on time-series data sets, where the goal is to classify the time-series as early as possible while still guaranteeing that the reliability threshold is met.« less

Change of choline compounds in sodium selenite-induced apoptosis of rats used as quantitative analysis by in vitro 9.4T MR spectroscopy.

PubMed

Cao, Zhen; Wu, Lin-Ping; Li, Yun-Xia; Guo, Yu-Bo; Chen, Yao-Wen; Wu, Ren-Hua

2008-06-28

To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrificed and the livers were dissected. (1)H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confirm the change of liver cells. Good (1)H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds, 5.08 +/- 0.97 mmol/L vs 3.81 +/- 1.16 mmol/L (P = 0.05); and free choline, 1.07 +/- 0.23 mmol/L vs 0.65 +/- 0.20 mmol/L (P = 0.00). However, there was no statistical significance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatment group were abnormal. Apoptosis of hepatic cells was confirmed by TUNEL assay. High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution (1)H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.

Comparing the efficacy and safety between propofol and dexmedetomidine for sedation in claustrophobic adults undergoing magnetic resonance imaging (PADAM trial).

PubMed

Loh, Pui-San; Ariffin, Mohd Azlan; Rai, Vineya; Lai, Lee-Lee; Chan, Lucy; Ramli, Norlisah

2016-11-01

To determine the efficacy of sedation with dexmedetomidine compared to propofol for claustrophobic adults undergoing magnetic resonance imaging (MRI) in our institution. Randomized, prospective, double-blinded study. University-based tertiary referral center. Thirty claustrophobic adults with American Society of Anesthesiologists physical status I and II who were planned for MRI. Patients were randomly assigned to target-controlled infusion propofol or dexmedetomidine loading followed by maintenance dose for procedural sedation. The primary end point was adequate reduction in patient anxiety levels to allow successful completion of the MRI sequence. Both methods of sedation adequately reduced anxiety levels in visual analog scale scores and Spielberger Strait Test Anxiety Inventory (P<.001). Dexmedetomidine required a longer time to achieve anxiolysis, 7.36minutes (SD, 2.59), and required increasing maintenance dose to induce sleep compared to 10.71minutes (SD, 4.63) for propofol. In terms of image quality, 2 patients (16.67%) in the dexmedetomidine group were satisfactory, whereas all with propofol were graded as good to excellent. Adverse effects were seen in patients sedated with dexmedetomidine with number needed to harm 8 for hypotension and 15 for bradycardia compared to none recorded in the propofol arm. There was no significant difference in patient satisfaction scores or home readiness after the MRI. Both dexmedetomidine and propofol can effectively reduce anxiety levels of claustrophobic adults undergoing MRI, but dexmedetomidine takes longer to achieve adequate anxiolysis and sleep and may have an effect on image quality. Hypotension and bradycardia are common adverse effects observed with dexmedetomidine. Copyright © 2016 Elsevier Inc. All rights reserved.

A Pilot Study of Women’s Affective Responses to Common and Uncommon Forms of Aerobic Exercise

PubMed Central

Stevens, Courtney J.; Smith, Jane Ellen; Bryan, Angela D.

2015-01-01

Objective To test the extent to which participants exposed to an uncommon versus common exercise stimulus would result in more favourable affect at post task. Design Experimental design. Participants, (N = 120) American women aged 18–45 years, were randomly assigned to complete 30-minutes of either the uncommon (HOOP; n = 58) or common (WALK; n = 62) exercise stimulus. Main Outcome Measures Self-reported affect and intentions for future exercise were measured before and after the 30-minute exercise bout. Results Analyses of covariance (ANCOVA) were run to compare post-task affect across the HOOP and WALK conditions. At post-task, participants assigned to HOOP reported more positively valenced affect, higher ratings of positive activated affect, lower ratings of negative deactivated affect, and stronger intentions for future aerobic exercise compared to participants assigned to WALK. Conclusions Participants who completed an uncommon bout of aerobic exercise (HOOP) reported more favourable affect post-exercise, as well as stronger intentions for future exercise, compared to participants who completed a common bout of aerobic exercise (WALK). Future work using a longitudinal design is needed to understand the relationships between familiarity with an exercise stimulus, affective responses to exercise, motivation for future exercise behaviour, and exercise maintenance over time. PMID:26394246

Scientist Spotlight Homework Assignments Shift Students’ Stereotypes of Scientists and Enhance Science Identity in a Diverse Introductory Science Class

PubMed Central

Schinske, Jeffrey N.; Perkins, Heather; Snyder, Amanda; Wyer, Mary

2016-01-01

Research into science identity, stereotype threat, and possible selves suggests a lack of diverse representations of scientists could impede traditionally underserved students from persisting and succeeding in science. We evaluated a series of metacognitive homework assignments (“Scientist Spotlights”) that featured counterstereotypical examples of scientists in an introductory biology class at a diverse community college. Scientist Spotlights additionally served as tools for content coverage, as scientists were selected to match topics covered each week. We analyzed beginning- and end-of-course essays completed by students during each of five courses with Scientist Spotlights and two courses with equivalent homework assignments that lacked connections to the stories of diverse scientists. Students completing Scientist Spotlights shifted toward counterstereotypical descriptions of scientists and conveyed an enhanced ability to personally relate to scientists following the intervention. Longitudinal data suggested these shifts were maintained 6 months after the completion of the course. Analyses further uncovered correlations between these shifts, interest in science, and course grades. As Scientist Spotlights require very little class time and complement existing curricula, they represent a promising tool for enhancing science identity, shifting stereotypes, and connecting content to issues of equity and diversity in a broad range of STEM classrooms. PMID:27587856

Impact of a radio frequency management information system on the process and timing of providing respiratory care services.

PubMed

Stoller, James K; Kester, Lucy; Orens, Douglas K; McCarthy, Kevin

2002-08-01

Although radio frequency (RF) systems have proliferated and are designed to simplify care delivery in many clinical settings, little information is available on the impact of such RF systems on the delivery of patient care. Having used a hand-held-device-based management information system in our Respiratory Therapy Section for 16 years, we assessed the impact of an RF system on the delivery of respiratory therapy (RT) services. A single nursing unit dedicated to pulmonary and ear, nose, and throat care was selected for the RF system trial. Baseline (pre-RF) data were collected over 2 separate 1-month intervals (February 1999 and February 2000). The main outcome measures were (1) the amount of time needed at the beginning of the shift to organize and assign orders for RT services, (2) the time interval between notification of an RT consult order and completion of the RT consult, and (3) the time interval between notification of an RT treatment order and completion of the RT treatment. The activities required for organizing and assigning the orders were manually timed. Starting 6 weeks after therapists were trained to use the RF system, similar data were collected while using the RF system for two 1-month intervals (February and March 2001). The mean +/- SD time interval between receiving an RT consult order and completing the consult was reduced from 7.8 +/- 18.9 h to 2.8 +/- 2.4 h (p = 0.002). The percentage of patients who waited longer than 8 hours between receipt of a consult order and completion of the consult decreased from 18% to 4.7% (p = 0.026). The total time required for organizing and assigning RT work was reduced from 81.6 min to 43.6 min. The RF system had several advantages over the hand-held-device-based system: (1) shorter interval between the order for and completion of an RT consult, (2) lower percentage of patients for whom the interval between the order and the consult exceeded 8 hours, and (3) less time required to make shift assignments. These results invite assessment of whether accelerated delivery of RT services confers clinical benefits.

The nature of the CO{sub 2}{sup −} radical anion in water

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

Janik, Ireneusz; Tripathi, G. N. R.

2016-04-21

The reductive conversion of CO{sub 2} into industrial products (e.g., oxalic acid, formic acid, methanol) can occur via aqueous CO{sub 2}{sup −} as a transient intermediate. While the formation, structure, and reaction pathways of this radical anion have been modelled for decades using various spectroscopic and theoretical approaches, we present here, for the first time, a vibrational spectroscopic investigation in liquid water, using pulse radiolysis time-resolved resonance Raman spectroscopy for its preparation and observation. Excitation of the radical in resonance with its 235 nm absorption displays a transient Raman band at 1298 cm{sup −1}, attributed to the symmetric CO stretch,more » which is at ∼45 cm{sup −1} higher frequency than in inert matrices. Isotopic substitution at C ({sup 13}CO{sub 2}{sup −}) shifts the frequency downwards by 22 cm{sup −1}, which confirms its origin and the assignment. A Raman band of moderate intensity compared to the stronger 1298 cm{sup −1} band also appears at 742 cm{sup −1} and is assignable to the OCO bending mode. A reasonable resonance enhancement of this mode is possible only in a bent CO{sub 2}{sup −}(C{sub 2v}/C{sub s}) geometry. These resonance Raman features suggest a strong solute-solvent interaction, the water molecules acting as constituents of the radical structure, rather than exerting a minor solvent perturbation. However, there is no evidence of the non-equivalence (C{sub s}) of the two CO bonds. A surprising resonance Raman feature is the lack of overtones of the symmetric CO stretch, which we interpret due to the detachment of the electron from the CO{sub 2}{sup −} moiety towards the solvation shell. Electron detachment occurs at the energies of 0.28 ± 0.03 eV or higher with respect to the zero point energy of the ground electronic state. The issue of acid-base equilibrium of the radical, which has been in contention for decades, as reflected in a wide variation in the reported pK{sub a} (−0.2 to 3.9), has been resolved. A value of 3.4 ± 0.2 measured in this work is consistent with the vibrational properties, bond structure, and charge distribution in aqueous CO{sub 2}{sup −}.« less

Calculation of the energy loss for an electron passing near giant fullerenes

NASA Astrophysics Data System (ADS)

Henrard, L.; Lambin, Ph

1996-11-01

We present a theoretical analysis of the electron energy-loss spectra of isolated giant fullerenes. We use a macroscopic dielectric description of spherical onion-like fullerenes and a discrete dipole approximation (DDA) framework for tubular fullerenes. In the DDA model, an anisotropic dynamical polarizability is assigned to each carbon site. We stress the fundamental importance of the hollow character of giant fullerenes in the electron energy-loss resonances.

Cross-polarization/magic-angle sample-spinning /sup 13/C NMR spectroscopic study of chlorophyll a in the solid state

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

Brown, C.E.; Spencer, R.B.; Burger, V.T.

1984-01-01

Solid-state cross-polarization/magic-angle sample-spinning /sup 13/C NMR spectra have been recorded on chlorophyll a-water aggregates, methyl pyrochlorophyllide a, and methyl pyropheophorbide a. Spectra have also been collected under a decoupling regime in which resonances of certain hydrogen-bearing carbon atoms are suppressed. These observations are used to assign the solid-state spectra. 18 references, 2 figures, 1 table.

13C nuclear magnetic resonance data of lanosterol derivatives—Profiling the steric topology of the steroid skeleton via substituent effects on its 13C NMR

NASA Astrophysics Data System (ADS)

Dias, Jerry Ray; Gao, Hongwu

2009-12-01

The 13C NMR spectra of over 24 tetracyclic triterpenoid derivatives have been structurally analyzed. The 13C NMR chemical shifts allow one to probe the steric topology of the rigid steroid skeleton and inductive effects of its substituents. Use of deuterium labeling in chemical shift assignment and B-ring aromatic terpenoids are also featured.

Solving the mystery of the internal structure of casein micelles.

PubMed

Ingham, B; Erlangga, G D; Smialowska, A; Kirby, N M; Wang, C; Matia-Merino, L; Haverkamp, R G; Carr, A J

2015-04-14

The interpretation of milk X-ray and neutron scattering data in relation to the internal structure of the casein micelle is an ongoing debate. We performed resonant X-ray scattering measurements on liquid milk and conclusively identified key scattering features, namely those corresponding to the size of and the distance between colloidal calcium phosphate particles. An X-ray scattering feature commonly assigned to the particle size is instead due to protein inhomogeneities.

Baryon spectroscopy and the omega minus

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

Samios, N.P.

1994-12-31

In this report, I will mainly discuss baryon resonances with emphasis on the discovery of the {Omega}{sup {minus}}. However, for completeness, I will also present some data on the meson resonances which together with the baryons led to the uncovering of the SU(3) symmetry of particles and ultimately to the concept of quarks.

Identification of disappearing brain lesions with intraoperative magnetic resonance imaging prevents surgery.

PubMed

Sutherland, Christina S; Kelly, John Jp; Morrish, William; Sutherland, Garnette R

2010-10-01

Typically, neurosurgery is performed several weeks after diagnostic imaging. In the majority of cases, histopathology confirms the diagnosis of neoplasia. In a small number of cases, a different diagnosis is established or histopathology is nondiagnostic. The frequency with which these outcomes occur has not been established. To determine the frequency and outcome of disappearing brain lesions within a group of patients undergoing surgery for suspected brain tumor. Over the past decade, 982 patients were managed in the intraoperative magnetic resonance imaging unit at the University of Calgary, Calgary, Alberta, Canada. These patients have been prospectively evaluated. In 652 patients, a brain tumor was suspected. In 6 of the 652 patients, histopathology indicated a nontumor diagnosis. In 5 patients, intraoperative images, acquired after induction of anesthesia, showed complete or nearly complete resolution of the suspected tumor identified on diagnostic magnetic resonance imaging acquired 6 ± 4 (mean ± SD) weeks previously. Anesthesia was reversed, and the surgical procedure aborted. The lesions have not progressed with 6 ± 2 years of follow-up. Intraoperative magnetic resonance imaging prevented surgery on 5 patients with disappearing lesions.

The Spin-orbit resonance of Mercury: a Hamiltonian approach

NASA Astrophysics Data System (ADS)

D'Hoedt, S.; Lemaitre, A.

2005-04-01

One of the main characteristics of Mercury is its 3:2 spin-orbit resonance, combined with a 1:1 resonance between the orbital node of its orbit and the angle describing the precession of the rotation axis, both measured on the ecliptic plane. We build an analytical model, using Hamiltonian formalism, that takes into account this phenomenon thanks to the introduction of three resonant variables and conjugated momenta. We calculate the equilibria corresponding to four different configurations, which means four completely different values of the (ecliptic) obliquity; in particular, we focus on the present (stable) situation of Mercury, and thanks to several canonical transformations, we obtain, near the equilibrium, three pairs of angle-action variables, and consequently, three basic frequencies. Let us note that the model is as simple as possible: the gravitational potential is limited to the second degree terms (the only ones for which a value can be presently given), and the orbit of Mercury is Keplerian. The numerical values obtained by our simplified model are validated by the coherence with existing complete numerical models.

Far-infrared laser magnetic resonance of vibrationally excited CD2

NASA Technical Reports Server (NTRS)

Evenson, K. M.; Sears, T. J.; Mckellar, A. R. W.

1984-01-01

The detection of 13 rotational transitions in the first excited bending state (010) of CD2 using the technique of far-infrared laser magnetic resonance spectroscopy is reported. Molecular parameters for this state are determined from these new data together with existing infrared observations of the v(2) band. Additional information on the ground vibrational state (000) is also provided by the observation of a new rotational transition, and this is combined with existing data to provide a refined set of molecular parameters for the CD2 ground state. One spectrum has been observed that is assigned as a rotational transition within the first excited symmetric stretching state (100) of CD2. These data will be of use in refining the structure and the potential function of the methylene radical.

Proton threshold states in the Na22(p,γ)Mg23 reaction and astrophysical implications

NASA Astrophysics Data System (ADS)

Comisel, H.; Hategan, C.; Graw, G.; Wolter, H. H.

2007-04-01

Proton threshold states in Mg23 are important for the astrophysically relevant proton capture reaction Na22(p,γ)Mg23. In the indirect determination of the resonance strength of the lowest states, which were not accessible by direct methods, some of the spin-parity-assignments remained experimentally uncertain. We have investigated these states with shell model, Coulomb displacement, and Thomas-Ehrman shift calculations. From the comparison of calculated and observed properties, we relate the lowest relevant resonance state at Ex=7643 keV to an excited 3/2+ state in accordance with a recent experimental determination by Jenkins From this we deduce significantly improved values for the Na22(p,γ)Mg23 reaction rate at stellar temperatures below T9=0.1 K.

A multioutput LLC-type parallel resonant converter

NASA Astrophysics Data System (ADS)

Liu, Rui; Lee, C. Q.; Upadhyay, Anand K.

1992-07-01

When an LLC-type parallel resonant converter (LLC-PRC) operates above resonant frequency, the switching transistors can be turned off at zero voltage. Further study reveals that the LLC-PRC possesses the advantage of lower converter voltage gain as compared with the conventional PRC. Based on analytic results, a complete set of design curves is obtained, from which a systematic design procedure is developed. Experimental results from a 150 W 150 kHz multioutput LLC-type PRC power supply are presented.

Computerized Measurement and Tracking of Acoustical Resonances.

DTIC Science & Technology

1982-12-01

inaccuracies which wace sweep cats dependent and data points which were not necassirily equaI~ly spaced. method c was not utr-I2.zsd ’lus to the i-nability...f the output. B. CONCLISIONS FROM rASK COMPLEITION Upon completing tasks 1 ani 2, it was determi-ned that method b (frequenzy synthes-:zer/phase...following method . The synthesizar outputs a frequency off resonance into the r-esonator and the lock-in analyzer is sampled one hundred times. The mean and

Photonic spectra of a Bragg microresonator with a ferroelectric resonator layer

NASA Astrophysics Data System (ADS)

Fedorova, Irina V.; Eliseeva, Svetlana V.; Sementsov, Dmitrij I.

2018-05-01

Transmission spectra of a photonic crystal resonator structure have been obtained where the Bragg dielectric mirrors contain a finite number of periods with an inverted order of layers and the resonator layer is made of a ferroelectric with a permittivity many times exceeding the permittivity of the layers in Bragg mirrors. Almost a complete transmission suppression was detected not only in the photonic band gap (except for a narrow region of the defect mode), but also outside the forbidden band.

Comparison of Cognitive-Behavioural Therapy and Psychodynamic Therapy in the Treatment of Anxiety among University Students: An Effectiveness Study

ERIC Educational Resources Information Center

Monti, Fiorella; Tonetti, Lorenzo; Ricci Bitti, Pio Enrico

2014-01-01

The aim of the present study was to compare the effectiveness of cognitive-behavioural (CBT) and psychodynamic (PDT) therapies in the treatment of anxiety among university students. To this aim, the Symptom Questionnaire (SQ) was completed by 30 students assigned to CBT and by 24 students assigned to PDT, both at the beginning and at the end of…

Assignment of protein sequences to existing domain and family classification systems: Pfam and the PDB.

PubMed

Xu, Qifang; Dunbrack, Roland L

2012-11-01

Automating the assignment of existing domain and protein family classifications to new sets of sequences is an important task. Current methods often miss assignments because remote relationships fail to achieve statistical significance. Some assignments are not as long as the actual domain definitions because local alignment methods often cut alignments short. Long insertions in query sequences often erroneously result in two copies of the domain assigned to the query. Divergent repeat sequences in proteins are often missed. We have developed a multilevel procedure to produce nearly complete assignments of protein families of an existing classification system to a large set of sequences. We apply this to the task of assigning Pfam domains to sequences and structures in the Protein Data Bank (PDB). We found that HHsearch alignments frequently scored more remotely related Pfams in Pfam clans higher than closely related Pfams, thus, leading to erroneous assignment at the Pfam family level. A greedy algorithm allowing for partial overlaps was, thus, applied first to sequence/HMM alignments, then HMM-HMM alignments and then structure alignments, taking care to join partial alignments split by large insertions into single-domain assignments. Additional assignment of repeat Pfams with weaker E-values was allowed after stronger assignments of the repeat HMM. Our database of assignments, presented in a database called PDBfam, contains Pfams for 99.4% of chains >50 residues. The Pfam assignment data in PDBfam are available at http://dunbrack2.fccc.edu/ProtCid/PDBfam, which can be searched by PDB codes and Pfam identifiers. They will be updated regularly.

Complete Firing-Rate Response of Neurons with Complex Intrinsic Dynamics

PubMed Central

Puelma Touzel, Maximilian; Wolf, Fred

2015-01-01

The response of a neuronal population over a space of inputs depends on the intrinsic properties of its constituent neurons. Two main modes of single neuron dynamics–integration and resonance–have been distinguished. While resonator cell types exist in a variety of brain areas, few models incorporate this feature and fewer have investigated its effects. To understand better how a resonator’s frequency preference emerges from its intrinsic dynamics and contributes to its local area’s population firing rate dynamics, we analyze the dynamic gain of an analytically solvable two-degree of freedom neuron model. In the Fokker-Planck approach, the dynamic gain is intractable. The alternative Gauss-Rice approach lifts the resetting of the voltage after a spike. This allows us to derive a complete expression for the dynamic gain of a resonator neuron model in terms of a cascade of filters on the input. We find six distinct response types and use them to fully characterize the routes to resonance across all values of the relevant timescales. We find that resonance arises primarily due to slow adaptation with an intrinsic frequency acting to sharpen and adjust the location of the resonant peak. We determine the parameter regions for the existence of an intrinsic frequency and for subthreshold and spiking resonance, finding all possible intersections of the three. The expressions and analysis presented here provide an account of how intrinsic neuron dynamics shape dynamic population response properties and can facilitate the construction of an exact theory of correlations and stability of population activity in networks containing populations of resonator neurons. PMID:26720924

Kinematic study of O--ion formation from dissociative electron attachment to SO2

NASA Astrophysics Data System (ADS)

Jana, Irina; Nandi, Dhananjay

2018-04-01

We report a complete kinematic study of O--ion formation due to dissociative electron attachment to SO2 using the velocity slice imaging technique in the incident electron energy range over the resonances. Two resonances are observed at 5.2 and 7.5 eV, respectively. From the kinetic energy distribution, the two resonances are observed to have the same threshold energy, pointing to the fact that the two processes, giving rise to the two resonant peaks, have the same dissociation limit. From the angular distribution results we identified the involvement of an A1 and a combination of A1+B2 temporary negative-ion state(s) for the first and second resonances, respectively.

Suspension Needn't Arrest Learning.

ERIC Educational Resources Information Center

Seegrist, Ruth

1985-01-01

An inschool suspension program at a Pennsylvania school district is described. Students spend suspension time completing classroom assignments under strict teacher supervision in detention halls. (TE)

Backbone ¹H, ¹³C, ¹⁵N NMR assignments of yeast OMP synthase in unliganded form and in complex with orotidine 5'-monophosphate.

PubMed

Hansen, Michael Riis; Harris, Richard; Barr, Eric W; Cheng, Hong; Girvin, Mark E; Grubmeyer, Charles

2014-04-01

The type I phosphoribosyltransferase OMP synthase (EC 2.4.2.10) is involved in de novo synthesis of pyrimidine nucleotides forming the UMP precursor orotidine 5'-monophosphate (OMP). The homodimeric enzyme has a Rossman α/β core topped by a base-enclosing "hood" domain and a flexible domain-swapped catalytic loop. High-resolution X-ray structures of the homologous Salmonella typhimurium and yeast enzymes show that a general compacting of the core as well as movement of the hood and a major disorder-to-order transition of the loop occur upon binding of ligands MgPRPP and orotate. Here we present backbone NMR assignments for the unliganded yeast enzyme (49 kDa) and its complex with product OMP. We were able to assign 212-213 of the 225 non-proline backbone (15)N and amide proton resonances. Significant difference in chemical shifts of the amide cross peaks occur in regions of the structure that undergo movement upon ligand occupancy in the S. typhimurium enzyme.

Assignment of selected hyperfine proton NMR resonances in the met forms of Glycera dibranchiata monomer hemoglobins and comparisons with sperm whale metmyoglobin

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

Constantinidis, I.; Satterlee, J.D.; Pandey, R.K.

1988-04-19

This work indicates a high degree of purity for our preparations of all three of the primary Glycera dibranchiata monomer hemoglobins and details assignments of the heme methyl and vinyl protons in the hyperfine shift region of the ferric (aquo.) protein forms. The assignments were carried out by reconstituting the apoproteins of each component with selectively deuteriated hemes. The results indicate that even though the individual component preparations consist of essentially a single protein, the proton NMR spectra indicate spectroscopic heterogeneity. Evidence is presented for identification and classification of major and minor protein forms that are present in solutions ofmore » each component. Finally, in contrast to previous results, a detailed analysis of the proton hyperfine shift patterns of the major and minor forms of each component, in comparison to the major and minor forms of metmyoglobin, leads to the conclusions that the corresponding forms of the proteins from each species have strikingly similar heme-globin contacts and display nearly identical heme electronic structures and coordination numbers.« less

A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing

PubMed Central

Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian

2015-01-01

The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m < n), such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP) complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation. PMID:26512650

Instructor-Facilitated vs. Stand-Alone Tactical Game Training

DTIC Science & Technology

2009-01-01

Mixed Factor Repeated-Measures ANOVA showed that the two groups of leaders did not differ significantly on the time they used to complete either the...game training on tactical decision making. Thirty- two leaders were assigned to complete two urban operations- based missions (patrol and defense...using the SimFX game. These leaders worked under the direction of an instructor and interacted with peers. Thirty-seven more leaders completed the two

Lack of dependence on resonant error field of locked mode island size in ohmic plasmas in DIII-D

DOE PAGES

Haye, R. J. La; Paz-Soldan, C.; Strait, E. J.

2015-01-23

DIII-D experiments show that fully penetrated resonant n=1 error field locked modes in Ohmic plasmas with safety factor q 95≳3 grow to similar large disruptive size, independent of resonant error field correction. Relatively small resonant (m/n=2/1) static error fields are shielded in Ohmic plasmas by the natural rotation at the electron diamagnetic drift frequency. However, the drag from error fields can lower rotation such that a bifurcation results, from nearly complete shielding to full penetration, i.e., to a driven locked mode island that can induce disruption.

Promoting Student Comprehension with Cooperative Learning

ERIC Educational Resources Information Center

Fernsten, Linda A.

2012-01-01

One study, covering the last 25 years, reports that undergraduates in college complete about 30 percent of assigned work. Would it be surprising--in these days of DVRs, Internet, texting, email, and video games--if high school and middle school students' homework completion rates were even less? What are teachers to do? Comprehension strategies,…

Preparing Child Witnesses: The Efficacy of Memory Strategy Training.

ERIC Educational Resources Information Center

Saywitz, Karen J.; And Others

An intervention to prepare children for pretrial interviews and testimony was tested. The goal of the intervention was to increase the completeness of young children's eyewitness accounts because their free recall is typically less complete than that of older children or adults. Seven- and 10-year-old children (N=132) were randomly assigned,…

Validation of a Formula for Assigning Continuing Education Credit to Printed Home Study Courses

PubMed Central

Hanson, Alan L.

2007-01-01

Objectives To reevaluate and validate the use of a formula for calculating the amount of continuing education credit to be awarded for printed home study courses. Methods Ten home study courses were selected for inclusion in a study to validate the formula, which is based on the number of words, number of final examination questions, and estimated difficulty level of the course. The amount of estimated credit calculated using the a priori formula was compared to the average amount of time required to complete each article based on pharmacists' self-reporting. Results A strong positive relationship between the amount of time required to complete the home study courses based on the a priori calculation and the times reported by pharmacists completing the 10 courses was found (p < 0.001). The correlation accounted for 86.2% of the total variability in the average pharmacist reported completion times (p < 0.001). Conclusions The formula offers an efficient and accurate means of determining the amount of continuing education credit that should be assigned to printed home study courses. PMID:19503705