Beta-decay spectroscopy relevant to the r-process nucleosynthesis

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

Nishimura, Shunji; Collaboration: RIBF Decay Collaboration

2012-11-12

A scientific program of beta-decay spectroscopy relevant to r-process nucleosynthesis has been started using high intensity U-beam at the RIBF. The first results of {beta}-decay half-lives of very neutron-rich Kr to Tc nuclides, all of which lie close to the r-process path, suggest a systematic enhancement of the the {beta}-decay rates of the Zr and Nb isotopes around A110 with respect to the predictions of the deformed quasiparticle-random-phase-approximation model (FRDM + QRPA). An impact of the results on the astrophysical r-process is discussed together with the future perspective of the {beta}-decay spectroscopy with the EURICA.

PRIMORDIAL r-PROCESS DISPERSION IN METAL-POOR GLOBULAR CLUSTERS

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

Roederer, Ian U., E-mail: iur@obs.carnegiescience.edu

Heavy elements, those produced by neutron-capture reactions, have traditionally shown no star-to-star dispersion in all but a handful of metal-poor globular clusters (GCs). Recent detections of low [Pb/Eu] ratios or upper limits in several metal-poor GCs indicate that the heavy elements in these GCs were produced exclusively by an r-process. Re-examining GC heavy element abundances from the literature, we find unmistakable correlations between the [La/Fe] and [Eu/Fe] ratios in four metal-poor GCs (M5, M15, M92, and NGC 3201), only two of which were known previously. This indicates that the total r-process abundances vary from star to star (by factors ofmore » 2-6) relative to Fe within each GC. We also identify potential dispersion in two other GCs (M3 and M13). Several GCs (M12, M80, and NGC 6752) show no evidence of r-process dispersion. The r-process dispersion is not correlated with the well-known light element dispersion, indicating that it was present in the gas throughout the duration of star formation. The observations available at present suggest that star-to-star r-process dispersion within metal-poor GCs may be a common but not ubiquitous phenomenon that is neither predicted by nor accounted for in current models of GC formation and evolution.« less

Nuclear structure for SNe r- and neutrino processes

NASA Astrophysics Data System (ADS)

Suzuki, Toshio

2014-09-01

SNe r- and neutrino-processes are investigated based on recent advances in the studies of spin responses in nuclei. New shell-model Hamiltonians, which can well describe spin responses in nuclei with proper tensor components, are used to make accurate evaluations of reaction cross sections and rates in astrophysical processes. Nucleosyntheses in SNe r- and ν -processes as well as rp-processes are discussed with these new reaction rates with improved accuracies. (1) Beta-decay rates for N = 126 isotones are evaluated by shell-model calculations, and new rates are applied to study r-process nucleosynthesis in SNe's around its third peak as well as beyond the peak region up to uranium. (2) ν -processes for light-element synthesis in core-collapse SNe are studied with a new shell-model Hamiltonian in p-shell, SFO. Effects of MSW ν -oscillations on the production yields of 7Li and 11B and sensitivity of the yield ratio on ν -oscillation parameters are discussed. ν -induced reactions on 16O are also studied. (3) A new shell-model Hamiltonian in pf-shell, GXPF1J, is used to evaluate e-capture rates in pf-shell nuclei at stellar environments. New e-capture rates are applied to study nucleosynthesis in type-Ia supernova explosions, rp-process and X-ray bursts.

RELATIVE CONTRIBUTIONS OF THE WEAK, MAIN, AND FISSION-RECYCLING r-PROCESS

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

Shibagaki, S.; Kajino, T.; Mathews, G. J.

There has been a persistent conundrum in attempts to model the nucleosynthesis of heavy elements by rapid neutron capture (the r-process). Although the locations of the abundance peaks near nuclear mass numbers 130 and 195 identify an environment of rapid neutron capture near closed nuclear shells, the abundances of elements just above and below those peaks are often underproduced by more than an order of magnitude in model calculations. At the same time, there is a debate in the literature as to what degree the r-process elements are produced in supernovae or the mergers of binary neutron stars. In thismore » paper we propose a novel solution to both problems. We demonstrate that the underproduction of nuclides above and below the r-process peaks in main or weak r-process models (like magnetohydrodynamic jets or neutrino-driven winds in core-collapse supernovae) can be supplemented via fission fragment distributions from the recycling of material in a neutron-rich environment such as that encountered in neutron star mergers (NSMs). In this paradigm, the abundance peaks themselves are well reproduced by a moderately neutron-rich, main r-process environment such as that encountered in the magnetohydrodynamical jets in supernovae supplemented with a high-entropy, weakly neutron-rich environment such as that encountered in the neutrino-driven-wind model to produce the lighter r-process isotopes. Moreover, we show that the relative contributions to the r-process abundances in both the solar system and metal-poor stars from the weak, main, and fission-recycling environments required by this proposal are consistent with estimates of the relative Galactic event rates of core-collapse supernovae for the weak and main r-process and NSMs for the fission-recycling r-process.« less

Rosen's (M,R) system in process algebra.

PubMed

Gatherer, Derek; Galpin, Vashti

2013-11-17

Robert Rosen's Metabolism-Replacement, or (M,R), system can be represented as a compact network structure with a single source and three products derived from that source in three consecutive reactions. (M,R) has been claimed to be non-reducible to its components and algorithmically non-computable, in the sense of not being evaluable as a function by a Turing machine. If (M,R)-like structures are present in real biological networks, this suggests that many biological networks will be non-computable, with implications for those branches of systems biology that rely on in silico modelling for predictive purposes. We instantiate (M,R) using the process algebra Bio-PEPA, and discuss the extent to which our model represents a true realization of (M,R). We observe that under some starting conditions and parameter values, stable states can be achieved. Although formal demonstration of algorithmic computability remains elusive for (M,R), we discuss the extent to which our Bio-PEPA representation of (M,R) allows us to sidestep Rosen's fundamental objections to computational systems biology. We argue that the behaviour of (M,R) in Bio-PEPA shows life-like properties.

The R-Process Alliance: 2MASS J09544277+5246414, the Most Actinide-enhanced R-II Star Known

NASA Astrophysics Data System (ADS)

Holmbeck, Erika M.; Beers, Timothy C.; Roederer, Ian U.; Placco, Vinicius M.; Hansen, Terese T.; Sakari, Charli M.; Sneden, Christopher; Liu, Chao; Lee, Young Sun; Cowan, John J.; Frebel, Anna

2018-06-01

We report the discovery of a new actinide-boost star, 2MASS J09544277+5246414, originally identified as a very bright (V = 10.1), extremely metal-poor ([Fe/H] = ‑2.99) K giant in the LAMOST survey, and found to be highly r-process-enhanced (r-II; [Eu/Fe] = +1.28]), during the snapshot phase of the R-Process Alliance (RPA). Based on a high signal-to-noise ratio (S/N), high-resolution spectrum obtained with the Harlan J. Smith 2.7 m telescope, this star is the first confirmed actinide-boost star found by RPA efforts. With an enhancement of [Th/Eu] = +0.37, 2MASS J09544277+5246414 is also the most actinide-enhanced r-II star yet discovered, and only the sixth metal-poor star with a measured uranium abundance ([U/Fe] = +1.40). Using the Th/U chronometer, we estimate an age of 13.0 ± 4.7 Gyr for this star. The unambiguous actinide-boost signature of this extremely metal-poor star, combined with additional r-process-enhanced and actinide-boost stars identified by the RPA, will provide strong constraints on the nature and origin of the r-process at early times.

R-process Enrichment in Cosmological Zoom Simulation of a Milkyway Type Halo by Neutron Star Mergers; The Origin of the MP-R and CEMP-R Stars

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Scannapieco, Evan

2018-06-01

The history of r-process enrichment in our galaxy is modeled through a novel set of zoom cosmo- logical simulations on a MilkyWay type galaxy. r-process sources are assumed to be neutron star mergers with a distribution of natal kicks and merge time distribution. We model turbulent mixing to estimate the pristine gas fraction in each simulation cell which we use to determine the Pop III star formation with assigned Carbon rich ejecta when going off as SNe. We follow the formation of Carbon-Enhanced Metal-Poor (CEMP) stars and the statistics of different r-process enhanced class of stars. The simulation underpredict the frequency of CEMP/MP stars by a factor of 2-4. Likewise the MP-rI/MP and MP-rII/MP and CEMP-r/CEMP cumulative ratios are all under predicted by 1-2 orders of magnitude. Our results show that NS binaries by themselves fall too short to explain the observed frequency of r-process enhanced stars and other sources of r-process enrichment at high redshifts are needed to fill the gap.

The r-process nucleosynthesis in an expanding hot bubble in supernovae explosion

NASA Astrophysics Data System (ADS)

Baruah, Rulee; Duorah, H. L.; Duorah, K.

2006-08-01

The r-process is one of the major nucleosynthesis processes responsible for the production of heavy elements beyond iron. Recent models of r-process nucleosynthesis rely on a neutrino-heated bubble developing at late times, which provides both the necessary conditions and the requisite amount of ejected mass for the r-process (Wooseley et al '94) . In the neutrino-driven explosion, only a small amount of matter is heated to the requisite high specific energy and entropy. Meyer et al (1992) first calculated the r-process under conditions appropriate to a neutrino-heated bubble and found that the solar r-process abundances could be replicated. They showed that the hot bubble that forms outside the protoneutron star during a SN explosion may be a viable site for the r-process as long as the entropy per baryon can be made sufficiently high. But in a very neutron rich environment such as a neutron star , the r-process could occur even at low entropy (Cowan and Thielemann, 2004). The high entropy wind is not the correct r-process site , owing to the inherent deficiencies in the abundance pattern below A=110 as well as the problems in obtaining the high entropies in SN II explosions required for producing the massive r-process nuclei up to A ≅ 195 and beyond ( Freiburghaus et al., 1999). Modelers of r-process nucleosynthesis find the entropy of the expanding matter and the overall n/p ratio to be more useful parameter than the temp and neutron density. We have tried to associate the explosion entropies with the site-independent classical approach (n[n] and T) and thereby compare the results of the two approaches from the abundances at different entropy conditions. We find that en entropy of ≈ 300 with Y[e] ≈ 0.45 can lead to a successful r-process. This is in agreement with the r-process abundance peaks at n[n] ≈ 10^32 cm^-3 and T[9] ≈ 1.5 . References : 1. Cowan J.J. and Thielemann F. K., Physics Today, 2004 2. Woosley S.E., Wilson J.R., Mathews G. J., Hoffman

R-process enrichment from a single event in an ancient dwarf galaxy.

PubMed

Ji, Alexander P; Frebel, Anna; Chiti, Anirudh; Simon, Joshua D

2016-03-31

Elements heavier than zinc are synthesized through the rapid (r) and slow (s) neutron-capture processes. The main site of production of the r-process elements (such as europium) has been debated for nearly 60 years. Initial studies of trends in chemical abundances in old Milky Way halo stars suggested that these elements are produced continually, in sites such as core-collapse supernovae. But evidence from the local Universe favours the idea that r-process production occurs mainly during rare events, such as neutron star mergers. The appearance of a plateau of europium abundance in some dwarf spheroidal galaxies has been suggested as evidence for rare r-process enrichment in the early Universe, but only under the assumption that no gas accretes into those dwarf galaxies; gas accretion favours continual r-process enrichment in these systems. Furthermore, the universal r-process pattern has not been cleanly identified in dwarf spheroidals. The smaller, chemically simpler, and more ancient ultrafaint dwarf galaxies assembled shortly after the first stars formed, and are ideal systems with which to study nucleosynthesis events such as the r-process. Reticulum II is one such galaxy. The abundances of non-neutron-capture elements in this galaxy (and others like it) are similar to those in other old stars. Here, we report that seven of the nine brightest stars in Reticulum II, observed with high-resolution spectroscopy, show strong enhancements in heavy neutron-capture elements, with abundances that follow the universal r-process pattern beyond barium. The enhancement seen in this 'r-process galaxy' is two to three orders of magnitude higher than that detected in any other ultrafaint dwarf galaxy. This implies that a single, rare event produced the r-process material in Reticulum II. The r-process yield and event rate are incompatible with the source being ordinary core-collapse supernovae, but consistent with other possible sources, such as neutron star mergers.

Modeling Neutron stars as r-process sources in Ultra Faint Dwarf galaxies

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Scannapieco, Evan

2018-06-01

To explain the high observed abundances of r-process elements in local ultrafaint dwarf (UFD) galaxies, we perform cosmological zoom simulations that include r-process production from neutron star mergers (NSMs). We model star formation stochastically and simulate two different haloes with total masses ≈108 M⊙ at z = 6. We find that the final distribution of [Eu/H] versus [Fe/H] is relatively insensitive to the energy by which the r-process material is ejected into the interstellar medium, but strongly sensitive to the environment in which the NSM event occurs. In one halo, the NSM event takes place at the centre of the stellar distribution, leading to high levels of r-process enrichment such as seen in a local UFD, Reticulum II (Ret II). In a second halo, the NSM event takes place outside of the densest part of the galaxy, leading to a more extended r-process distribution. The subsequent star formation occurs in an interstellar medium with shallow levels of r-process enrichment that results in stars with low levels of [Eu/H] compared to Ret II stars even when the maximum possible r-process mass is assumed to be ejected. This suggests that the natal kicks of neutron stars may also play an important role in determining the r-process abundances in UFD galaxies, a topic that warrants further theoretical investigation.

Simulating neutron star mergers as r-process sources in ultrafaint dwarf galaxies

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Scannapieco, Evan

2017-10-01

To explain the high observed abundances of r-process elements in local ultrafaint dwarf (UFD) galaxies, we perform cosmological zoom simulations that include r-process production from neutron star mergers (NSMs). We model star formation stochastically and simulate two different haloes with total masses ≈108 M⊙ at z = 6. We find that the final distribution of [Eu/H] versus [Fe/H] is relatively insensitive to the energy by which the r-process material is ejected into the interstellar medium, but strongly sensitive to the environment in which the NSM event occurs. In one halo, the NSM event takes place at the centre of the stellar distribution, leading to high levels of r-process enrichment such as seen in a local UFD, Reticulum II (Ret II). In a second halo, the NSM event takes place outside of the densest part of the galaxy, leading to a more extended r-process distribution. The subsequent star formation occurs in an interstellar medium with shallow levels of r-process enrichment that results in stars with low levels of [Eu/H] compared to Ret II stars even when the maximum possible r-process mass is assumed to be ejected. This suggests that the natal kicks of neutron stars may also play an important role in determining the r-process abundances in UFD galaxies, a topic that warrants further theoretical investigation.

Impact of individual nuclear masses on r -process abundances

DOE PAGES

Mumpower, M. R.; Surman, R.; Fang, D. -L.; ...

2015-09-15

We have performed for the first time a comprehensive study of the sensitivity of r-process nucleosynthesis to individual nuclear masses across the chart of nuclides. Using the latest version (2012) of the Finite-Range Droplet Model, we consider mass variations of ±0.5 MeV and propagate each mass change to all affected quantities, including Q values, reaction rates, and branching ratios. We find such mass variations can result in up to an order of magnitude local change in the final abundance pattern produced in an r-process simulation. As a result, we identify key nuclei whose masses have a substantial impact on abundancemore » predictions for hot, cold, and neutron star merger r-process scenarios and could be measured at future radioactive beam facilities.« less

Nuclear robustness of the r process in neutron-star mergers

NASA Astrophysics Data System (ADS)

Mendoza-Temis, Joel de Jesús; Wu, Meng-Ru; Langanke, Karlheinz; Martínez-Pinedo, Gabriel; Bauswein, Andreas; Janka, Hans-Thomas

2015-11-01

We have performed r -process calculations for matter ejected dynamically in neutron star mergers based on a complete set of trajectories from a three-dimensional relativistic smoothed particle hydrodynamic simulation with a total ejected mass of ˜1.7 ×10-3M⊙ . Our calculations consider an extended nuclear network, including spontaneous, β - and neutron-induced fission and adopting fission yield distributions from the abla code. In particular we have studied the sensitivity of the r -process abundances to nuclear masses by using different models. Most of the trajectories, corresponding to 90% of the ejected mass, follow a relatively slow expansion allowing for all neutrons to be captured. The resulting abundances are very similar to each other and reproduce the general features of the observed r -process abundance (the second and third peaks, the rare-earth peak, and the lead peak) for all mass models as they are mainly determined by the fission yields. We find distinct differences in the predictions of the mass models at and just above the third peak, which can be traced back to different predictions of neutron separation energies for r -process nuclei around neutron number N =130 . In all simulations, we find that the second peak around A ˜130 is produced by the fission yields of the material that piles up in nuclei with A ≳250 due to the substantially longer β -decay half-lives found in this region. The third peak around A ˜195 is generated in a competition between neutron captures and β decays during r -process freeze-out. The remaining trajectories, which contribute 10% by mass to the total integrated abundances, follow such a fast expansion that the r process does not use all the neutrons. This also leads to a larger variation of abundances among trajectories, as fission does not dominate the r -process dynamics. The resulting abundances are in between those associated to the r and s processes. The total integrated abundances are dominated by

An r-process enhanced star in the dwarf galaxy Tucana III

DOE PAGES

Hansen, T. T.; Simon, J. D.; Marshall, J. L.; ...

2017-03-20

Chemically peculiar stars in dwarf galaxies provide a window for exploring the birth environment of stars with varying chemical enrichment. We present a chemical abundance analysis of the brightest star in the newly discovered ultra-faint dwarf galaxy candidate Tucana III. Because it is particularly bright for a star in an ultra-faint Milky Way (MW) satellite, we are able to measure the abundance of 28 elements, including 13 neutron-capture species. This star, DES J235532.66–593114.9 (DES J235532), shows a mild enhancement in neutron-capture elements associated with the r-process and can be classified as an r-I star. DES J235532 is the first r-Imore » star to be discovered in an ultra-faint satellite, and Tuc III is the second extremely low-luminosity system found to contain r-process enriched material, after Reticulum II. Comparison of the abundance pattern of DES J235532 with r-I and r-II stars found in other dwarf galaxies and in the MW halo suggests a common astrophysical origin for the neutron-capture elements seen in all r-process enhanced stars. Furthermore, we explore both internal and external scenarios for the r-process enrichment of Tuc III and show that with abundance patterns for additional stars, it should be possible to distinguish between them.« less

An r-process enhanced star in the dwarf galaxy Tucana III

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

Hansen, T. T.; Simon, J. D.; Marshall, J. L.

Chemically peculiar stars in dwarf galaxies provide a window for exploring the birth environment of stars with varying chemical enrichment. We present a chemical abundance analysis of the brightest star in the newly discovered ultra-faint dwarf galaxy candidate Tucana III. Because it is particularly bright for a star in an ultra-faint Milky Way (MW) satellite, we are able to measure the abundance of 28 elements, including 13 neutron-capture species. This star, DES J235532.66–593114.9 (DES J235532), shows a mild enhancement in neutron-capture elements associated with the r-process and can be classified as an r-I star. DES J235532 is the first r-Imore » star to be discovered in an ultra-faint satellite, and Tuc III is the second extremely low-luminosity system found to contain r-process enriched material, after Reticulum II. Comparison of the abundance pattern of DES J235532 with r-I and r-II stars found in other dwarf galaxies and in the MW halo suggests a common astrophysical origin for the neutron-capture elements seen in all r-process enhanced stars. Furthermore, we explore both internal and external scenarios for the r-process enrichment of Tuc III and show that with abundance patterns for additional stars, it should be possible to distinguish between them.« less

β-decay spectroscopy for the r-process nucleosynthesis

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

Nishimura, Shunji; Collaboration: RIBF Decay Collaborations

2014-05-09

Series of decay spectroscopy experiments, utilizing of high-purity Ge detectors and double-sided silicon-strip detectors, have been conducted to harvest the decay properties of very exotic nuclei relevant to the r-process nucleosynthesis at the RIBF. The decay properties such as β-decay half-lives, low-lying states, β-delayed neutron emissions, isomeric states, and possibly Q{sub β} of the very neutron-rich nuclei are to be measured to give significant constraints in the uncertainties of nuclear properties for the r-process nucleosynthesis. Recent results of βγ spectroscopy study using in-flight fission of {sup 238}U-beam will be presented together with our future perspectives.

Fission properties of superheavy nuclei for r -process calculations

NASA Astrophysics Data System (ADS)

Giuliani, Samuel A.; Martínez-Pinedo, Gabriel; Robledo, Luis M.

2018-03-01

We computed a new set of static fission properties suited for r -process calculations. The potential energy surfaces and collective inertias of 3640 nuclei in the superheavy region are obtained from self-consistent mean-field calculations using the Barcelona-Catania-Paris-Madrid energy density functional. The fission path is computed as a function of the quadrupole moment by minimizing the potential energy and exploring octupole and hexadecapole deformations. The spontaneous fission lifetimes are evaluated employing different schemes for the collective inertias and vibrational energy corrections. This allows us to explore the sensitivity of the lifetimes to those quantities together with the collective ground-state energy along the superheavy landscape. We computed neutron-induced stellar reaction rates relevant for r -process nucleosynthesis using the Hauser-Feshbach statistical approach and study the impact of collective inertias. The competition between different reaction channels including neutron-induced rates, spontaneous fission, and α decay is discussed for typical r -process conditions.

Beta-Decay Rates for Exotic Nuclei and R-Process Nucleosynthesis

NASA Astrophysics Data System (ADS)

Suzuki, Toshio; Yoshida, Takashi; Wanajo, Shinya; Kajino, Toshitaka; Otsuka, Takaharu

Beta-decay rates for exotic nuclei at N = 126 relevant to r-process nucleosynthesis are studied by shell-model calculations. The half-lives obtained are used to study r-process nucleosynthesis in core-collapse supernova explosions and binary neutron star mergers. The element abundances are obtained up to the third peak as well as beyond the peak region up to uranium.

New developments in understanding the r-process from observations of metal-poor stars

NASA Astrophysics Data System (ADS)

Frebel, Anna

2015-04-01

In their atmospheres, old metal-poor Galactic stars retain detailed information about the chemical composition of the interstellar medium at the time of their birth. Extracting such stellar abundances enables us to reconstruct the beginning of the chemical evolution shortly after the Big Bang. About 5% of metal-poor stars with [Fe/H] < - 2 . 5 display in their spectrum a strong enhancement of neutron-capture elements associated with the rapid (r-) nucleosynthesis process that is responsible for the production of the heaviest elements in the Universe. This fortuity provides a unique opportunity of bringing together astrophysics and nuclear physics because these objects act as ``cosmic lab'' for both fields of study. The so-called r-process stars are thought to have formed from material enriched in heavy neutron-capture elements that were created during an r-process event in a previous generation supernova. It appears that the few stars known with this rare chemical signature all follow the scaled solar r-process pattern (for the heaviest elements with 56 <= Z <= 90 that is). This suggests that the r-process is universal - a surprising empirical finding and a solid result that can not be obtained from any laboratory on earth. While much research has been devoted to establishing this pattern, little attention has been given to the overall level of enhancement. New results will be presented on the full extent of r-process element enrichment as observed in metal-poor stars. The challenge lies in determining how the r-process material in the earliest gas clouds was mixed and diluted. Assuming individual r-process events to have contributed the observed r-process elements. We provide empirical estimates on the amount of r-process material produced. This should become a crucial constraint for theoretical nuclear physics models of heavy element nucleosynthesis.

β-decay studies of r-process nuclei at NSCL

NASA Astrophysics Data System (ADS)

Pereira, J.; Aprahamian, A.; Arndt, O.; Becerril, A.; Elliot, T.; Estrade, A.; Galaviz, D.; Hennrich, S.; Hosmer, P.; Schnorrenberger, L.; Kessler, R.; Kratz, K.-L.; Lorusso, G.; Mantica, P. F.; Matos, M.; Montes, F.; Pfeiffer, B.; Quinn, M.; Santi, P.; Schatz, H.; Schertz, F.; Smith, E.; Tomlin, B. E.; Walters, W. B.; Wöhr, A.

2008-06-01

Observed neutron-capture elemental abundances in metal-poor stars, along with ongoing analysis of the extremely metal-poor Eu-enriched sub-class provide new guidance for astrophysical models aimed at finding the r-process sites. The present paper emphasizes the importance of nuclear physics parameters entering in these models, particularly β-decay properties of neutron-rich nuclei. In this context, several r-process motivated β-decay experiments performed at the National Superconducting Cyclotron Laboratory (NSCL) are presented, including a summary of results and impact on model calculations.

The Origin of r-process Elements in the Milky Way

NASA Astrophysics Data System (ADS)

Côté, Benoit; Fryer, Chris L.; Belczynski, Krzysztof; Korobkin, Oleg; Chruślińska, Martyna; Vassh, Nicole; Mumpower, Matthew R.; Lippuner, Jonas; Sprouse, Trevor M.; Surman, Rebecca; Wollaeger, Ryan

2018-03-01

Some of the heavy elements, such as gold and europium (Eu), are almost exclusively formed by the rapid neutron capture process (r-process). However, it is still unclear which astrophysical site between core-collapse supernovae and neutron star–neutron star (NS–NS) mergers produced most of the r-process elements in the universe. Galactic chemical evolution (GCE) models can test these scenarios by quantifying the frequency and yields required to reproduce the amount of europium (Eu) observed in galaxies. Although NS–NS mergers have become popular candidates, their required frequency (or rate) needs to be consistent with that obtained from gravitational wave measurements. Here, we address the first NS–NS merger detected by LIGO/Virgo (GW170817) and its associated gamma-ray burst and analyze their implication for the origin of r-process elements. The range of NS–NS merger rate densities of 320–4740 Gpc‑3 yr‑1 provided by LIGO/Virgo is remarkably consistent with the range required by GCE to explain the Eu abundances in the Milky Way with NS–NS mergers, assuming the solar r-process abundance pattern for the ejecta. Under the same assumption, this event has produced about 1–5 Earth masses of Eu, and 3–13 Earth masses of gold. When using theoretical calculations to derive Eu yields, constraining the role of NS–NS mergers becomes more challenging because of nuclear astrophysics uncertainties. This is the first study that directly combines nuclear physics uncertainties with GCE calculations. If GW170817 is a representative event, NS–NS mergers can produce Eu in sufficient amounts and are likely to be the main r-process site.

Extinct Radioactivities and the R-Process Jet

NASA Technical Reports Server (NTRS)

Cameron, A. G. W.

2001-01-01

All extinct radioactive species in the solar nebula were injected from a core-collapse supernova. I discuss primarily the products expected from an r-process jet in this supernova, and various supporting astrophysical observations. Additional information is contained in the original extended abstract.

DETECTION OF THE SECOND r-PROCESS PEAK ELEMENT TELLURIUM IN METAL-POOR STARS ,

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

Roederer, Ian U.; Lawler, James E.; Cowan, John J.

2012-03-15

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD +17 3248, HD 108317, and HD 128279. Tellurium (Te, Z = 52) is found at the second r-process peak (A Almost-Equal-To 130) associated with the N = 82 neutron shell closure, and it has not been detected previously in Galactic halo stars. The derived tellurium abundances match the scaled solar system r-process distribution within the uncertainties, confirming the predicted second peak r-process residuals. These results suggest that tellurium ismore » predominantly produced in the main component of the r-process, along with the rare earth elements.« less

Probing r-Process Production of Nuclei Beyond 209Bi with Gamma Rays

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

Qian, Y.-Z.; Vogel, P.; Wasserburg, G. J.

We estimate gamma-ray fluxes due to the decay of nuclei beyond 209Bi from a supernova or a supernova remnant assuming that the r-process occurs in supernovae. We find that a detector with a sensitivity of {approx}10-7 {gamma} cm-2 s-1 at energies from {approx}40 keV to {approx}3 MeV may detect fluxes due to the decay of 226Ra, 229Th, 241Am, 243Am, 249Cf, and 251Cf in the newly discovered supernova remnant near Vela. In addition, such a detector may detect fluxes due to the decay of 227Ac and 228Ra produced in a future supernova at a distance of {approx}1 kpc. Because nuclei withmore » mass numbers A>209 are produced solely by the r-process, such detections are the best proof for a supernova r-process site. Further, they provide the most direct information on yields of progenitor nuclei with A>209 at r-process freeze-out. Finally, detection of fluxes due to the decay of r-process nuclei over a range of masses from a supernova or a supernova remnant provides the opportunity to compare yields in a single supernova event with the solar r-process abundance pattern. (c) (c) 1999. The American Astronomical Society.« less

The r-process nucleosynthesis and related challenges

NASA Astrophysics Data System (ADS)

Goriely, Stephane; Bauswein, Andreas; Janka, Hans-Thomas; Just, Oliver; Pllumbi, Else

2018-01-01

The rapid neutron-capture process, or r-process, is known to be of fundamental importance for explaining the origin of approximately half of the A > 60 stable nuclei observed in nature. Recently, special attention has been paid to neutron star (NS) mergers following the confirmation by hydrodynamic simulations that a non-negligible amount of matter can be ejected and by nucleosynthesis calculations combined with the predicted astrophysical event rate that such a site can account for the majority of r-material in our Galaxy. We show here that the combined contribution of both the dynamical (prompt) ejecta expelled during binary NS or NS-black hole (BH) mergers and the neutrino and viscously driven outflows generated during the post-merger remnant evolution of relic BH-torus systems can lead to the production of r-process elements from mass number A ≳ 90 up to actinides. The corresponding abundance distribution is found to reproduce the solar distribution extremely well. It can also account for the elemental distributions observed in low-metallicity stars. However, major uncertainties still affect our understanding of the composition of the ejected matter. These concern (i) the β-interactions of electron (anti)neutrinos with free neutrons and protons, as well as their inverse reactions, which may affect the neutron-richness of the matter at the early phase of the ejection, and (ii) the nuclear physics of exotic neutron-rich nuclei, including nuclear structure as well as nuclear interaction properties, which impact the calculated abundance distribution. Both aspects are discussed in the light of recent hydrodynamical simulations of NS mergers and microscopic calculations of nuclear decay and reaction probabilities.

Collective neutrino oscillations and r-process nucleosynthesis in supernovae

NASA Astrophysics Data System (ADS)

Duan, Huaiyu

2012-10-01

Neutrinos can oscillate collectively in a core-collapse supernova. This phenomenon can occur much deeper inside the supernova envelope than what is predicted from the conventional matter-induced Mikheyev-Smirnov-Wolfenstein effect, and hence may have an impact on nucleosynthesis. The oscillation patterns and the r-process yields are sensitive to the details of the emitted neutrino fluxes, the sign of the neutrino mass hierarchy, the modeling of neutrino oscillations and the astrophysical conditions. The effects of collective neutrino oscillations on the r-process will be illustrated using representative late-time neutrino spectra and outflow models.

Fission in R-processes Elements (FIRE) - Annual Report: Fiscal Year 2017

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

Schunck, Nicolas

The goal of the FIRE topical collaboration in nuclear theory is to determine the astrophysical conditions of the rapid neutron capture process (r-process), which is responsible for the formation of heavy elements. This will be achieved by including in r-process simulations the most advanced models of fission (spontaneous, neutron-induced, beta-delayed) that have been developed at LLNL and LANL. The collaboration is composed of LLNL (lead) and LANL for work on nuclear data (ground-state properties, fission, beta-decay), BNL for nuclear data management, and the university of Notre Dame and North Carolina State University for r-process simulations. Under DOE/NNSA agreement, both universitiesmore » receive funds from the DOE Office of Science, while national laboratories receive funds directly from NA221.« less

ACToR Chemical Structure processing using Open Source ...

EPA Pesticide Factsheets

ACToR (Aggregated Computational Toxicology Resource) is a centralized database repository developed by the National Center for Computational Toxicology (NCCT) at the U.S. Environmental Protection Agency (EPA). Free and open source tools were used to compile toxicity data from over 1,950 public sources. ACToR contains chemical structure information and toxicological data for over 558,000 unique chemicals. The database primarily includes data from NCCT research programs, in vivo toxicity data from ToxRef, human exposure data from ExpoCast, high-throughput screening data from ToxCast and high quality chemical structure information from the EPA DSSTox program. The DSSTox database is a chemical structure inventory for the NCCT programs and currently has about 16,000 unique structures. Included are also data from PubChem, ChemSpider, USDA, FDA, NIH and several other public data sources. ACToR has been a resource to various international and national research groups. Most of our recent efforts on ACToR are focused on improving the structural identifiers and Physico-Chemical properties of the chemicals in the database. Organizing this huge collection of data and improving the chemical structure quality of the database has posed some major challenges. Workflows have been developed to process structures, calculate chemical properties and identify relationships between CAS numbers. The Structure processing workflow integrates web services (PubChem and NIH NCI Cactus) to d

COMPLETE ELEMENT ABUNDANCES OF NINE STARS IN THE r -PROCESS GALAXY RETICULUM II

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

Ji, Alexander P.; Frebel, Anna; Chiti, Anirudh

We present chemical abundances derived from high-resolution Magellan /Magellan Inamori Kyocera Echelle spectra of the nine brightest known red giant members of the ultra-faint dwarf galaxy Reticulum II (Ret II). These stars span the full metallicity range of Ret II (−3.5 < [Fe/H] < −2). Seven of the nine stars have extremely high levels of r -process material ([Eu/Fe] ∼ 1.7), in contrast to the extremely low neutron-capture element abundances found in every other ultra-faint dwarf galaxy studied to date. The other two stars are the most metal-poor stars in the system ([Fe/H] < −3), and they have neutron-capture elementmore » abundance limits similar to those in other ultra-faint dwarf galaxies. We confirm that the relative abundances of Sr, Y, and Zr in these stars are similar to those found in r -process halo stars, but they are ∼0.5 dex lower than the solar r -process pattern. If the universal r -process pattern extends to those elements, the stars in Ret II display the least contaminated known r -process pattern. The abundances of lighter elements up to the iron peak are otherwise similar to abundances of stars in the halo and in other ultra-faint dwarf galaxies. However, the scatter in abundance ratios is large enough to suggest that inhomogeneous metal mixing is required to explain the chemical evolution of this galaxy. The presence of low amounts of neutron-capture elements in other ultra-faint dwarf galaxies may imply the existence of additional r -process sites besides the source of r -process elements in Ret II. Galaxies like Ret II may be the original birth sites of r -process enhanced stars now found in the halo.« less

Contribution of fission to heavy-element nucleosynthesis in an astrophysical r-process

NASA Astrophysics Data System (ADS)

Korneev, I. Yu.; Panov, I. V.

2011-12-01

During the formation of heavy elements in the neutron star merger (NSM) scenario with a fairly long duration of the r-process, most of the seed nuclei rapidly burn out at the initial stage. The nucleosynthesis wave rapidly reaches the region of actinoids, where beta-delayed, neutron-induced, and spontaneous fission are the main reaction channels. The fission products of transuranium elements are again drawn into the r-process as new seed nuclei to form the yields of elements with mass numbers A > 100. The contribution from the various types of fission to the formation of heavy and superheavy nuclei is investigated. The proposed r-process model applied to the NSM scenario describes well the observed abundances of chemical elements, which confirms the formation of the main r-process component in the NSM scenario. Simple extrapolations of the spontaneous fission half-lives are shown to be inapplicable for the region of nuclei with N ˜ 184, because the formulas do not reflect the increase in half-life when the shell structure changes as the number of neutrons approaches 184. The formation of superheavy elements in the r-process is possible, but their survival depends to a large extent on how reliable the predictions of nuclear parameters, including the half-lives of the forming nuclei from the island of long-lived isotopes, are. The contributions from various types of fission—neutron-induced, beta-delayed, and spontaneous one—to the formation of heavy elements in the main r-process have been determined.

The r-, s-, and p-Processes in Nucleosynthesis

NASA Technical Reports Server (NTRS)

Meyer, Bradley S.

1994-01-01

A goal of this paper is to review the recent progress astrophysicists, astronomers, and physicists have made in the r-, s-, and p-processes in nucleosynthesis and to point out the problems that remain in our understanding of the formation of the heavy nuclei. Another, perhaps deeper, goal is to to seek some understanding of why there are three major processes available to nature for synthesis of heavy elements.

Primordial Black Holes and r-Process Nucleosynthesis.

PubMed

Fuller, George M; Kusenko, Alexander; Takhistov, Volodymyr

2017-08-11

We show that some or all of the inventory of r-process nucleosynthesis can be produced in interactions of primordial black holes (PBHs) with neutron stars (NSs) if PBHs with masses 10^{-14}  M_{⊙}process and the accompanying decompression and decay of nuclear matter can produce electromagnetic transients, such as a kilonova-type afterglow and fast radio bursts. These transients are not accompanied by significant gravitational radiation or neutrinos, allowing such events to be differentiated from compact object mergers occurring within the distance sensitivity limits of gravitational-wave observatories. The PBH-NS destruction scenario is consistent with pulsar and NS statistics, the dark-matter content, and spatial distributions in the Galaxy and ultrafaint dwarfs, as well as with the r-process content and evolution histories in these sites. Ejected matter is heated by beta decay, which leads to emission of positrons in an amount consistent with the observed 511-keV line from the Galactic center.

Reverse engineering nuclear properties from rare earth abundances in the r process

NASA Astrophysics Data System (ADS)

Mumpower, M. R.; McLaughlin, G. C.; Surman, R.; Steiner, A. W.

2017-03-01

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths around A∼ 160, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. We explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. We conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.

R-process experiments with the Advanced Implantation Detector Array

NASA Astrophysics Data System (ADS)

Estrade, Alfredo; Griffin, Chris; Davinson, Tom; Bruno, Carlo; Hall, Oscar; Liu, Zhong; Woods, Phil; Coleman-Smith, Patrick; Labiche, Marc; Lazarus, Ian; Pucknell, Victor; Simpson, John; Harkness-Brennan, Laura; Page, Robert; Kiss, Gabor; Liu, Jiajiang; Matsui, Keishi; Nishimura, Shunji; Phong, Vi; Lorusso, Giuseppe; Montes, Fernando; Nepal, Neerajan; Briken Collaboration; Ribf106 Experiment Team

2017-09-01

Decay properties of neutron rich isotopes, such as half-lives and β-delayed neutron emission probabilities, are an important input for astrophysical models of the r-process. A new generation of fragmentation beam facilities has made it possible to access large regions of the nuclear chart that are close to the path of the r-process for some astrophysical models. The Advanced Implantation Detector Array (AIDA) is a segmented active-stopper detector designed for decay experiments with fast ion beams, which was recently commissioned at the Radioactive Ion Beam Factory in RIKEN, Japan. In this presentation we describe the main characteristics of AIDA, and present preliminary results of the first experiments in the region of neutron-rich selenium isotopes and along the N=82 shell closure.

Reverse engineering nuclear properties from rare earth abundances in the r process

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

Mumpower, Matthew Ryan; McLaughlin, G. C.; Surman, R.

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths aroundmore » $$A\\sim 160$$, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. Here, we explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. Finally, we conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.« less

Reverse engineering nuclear properties from rare earth abundances in the r process

DOE PAGES

Mumpower, Matthew Ryan; McLaughlin, G. C.; Surman, R.; ...

2017-02-01

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths aroundmore » $$A\\sim 160$$, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. Here, we explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. Finally, we conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.« less

Impact of (α, n) reactions on weak r-process in neutrino-driven winds

NASA Astrophysics Data System (ADS)

Bliss, J.; Arcones, A.; Montes, F.; Pereira, J.

2017-05-01

After a successful core-collapse supernova, a neutrino-driven wind develops where it is possible to synthesize lighter heavy elements (30 < Z < 45). In the early galaxy, the origin of these elements is associated with the r-process and to an additional process. Here we assume that the additional process corresponds to the weak r-process (sometimes referred to as alpha-process) taking place in neutrino-driven winds. Based on a trajectory obtained from hydrodynamical simulations we study the astrophysics and nuclear physics uncertainties of a weak r-process with our main focus on the (α, n) reactions. These reactions are critical to redistribute the matter and allow it to move from light to heavy elements after nuclear statistical equilibrium freezes out. In this first sensitivity study, we vary all (α, n) reactions by given constant factors which are justified based on the uncertainties of the statistical model and its nuclear physics input, mainly alpha optical potentials for weak r-process conditions. Our results show that (α, n) rate uncertainties are indeed crucial to predict abundances. Therefore, further studies will follow to identify individual critical reactions. Since the nucleosynthesis path is close to stability, these reactions can be measured in the near future. Since much of the other nuclear data for the weak r-process are known, the reduction in nuclear physics uncertainties provided by these experiments will allow astronomical observations to directly constrain the astronomical conditions in the wind.

R-process Element Cosmic Rays from Neutron Star Mergers

NASA Astrophysics Data System (ADS)

Komiya, Yutaka; Shigeyama, Toshikazu

2017-09-01

Neutron star mergers (NSMs) are one of the most plausible sources of r-process elements in the universe. Therefore, NSMs can also be a major source of ultra-heavy elements in cosmic rays. In this paper, we first estimate the contribution of r-process elements synthesized in NSMs to the ultra-heavy element cosmic rays (UHCRs) by calculating transport equations that take into account energy loss processes and spallations. We show that the flux of UHCRs accelerated by the NSMs themselves fluctuates by many orders of magnitude on a timescale of several million years and can overwhelm UHCRs accelerated by supernova remnants (SNRs) after an NSM takes place within a few kiloparsec from the solar system. Experiments with very long exposure times using meteorites as UHCR detectors can detect this fluctuation. As a consequence, we show that if NSMs are the primary source of UHCRs, future experiments using meteorites may be able to reveal the event history of NSMs in the solar vicinity. We also describe a possible difference in the abundance pattern and energy spectrum of UHCRs between NSM and SNR accelerations.

The impact of nuclear mass models on r-process nucleosynthesis network calculations

NASA Astrophysics Data System (ADS)

Vaughan, Kelly

2002-10-01

An insight into understanding various nucleosynthesis processes is via modelling of the process with network calculations. My project focus is r-process network calculations where the r-process is nucleosynthesis via rapid neutron capture thought to take place in high entropy supernova bubbles. One of the main uncertainties of the simulations is the Nuclear Physics input. My project investigates the role that nuclear masses play in the resulting abundances. The code tecode, involves rapid (n,γ) capture reactions in competition with photodisintegration and β decay onto seed nuclei. In order to fully analyze the effects of nuclear mass models on the relative isotopic abundances, calculations were done from the network code, keeping the initial environmental parameters constant throughout. The supernova model investigated by Qian et al (1996) in which two r-processes, of high and low frequency with seed nucleus ^90Se and of fixed luminosity (fracL_ν_e(0)r_7(0)^2 ˜= 8.77), contribute to the nucleosynthesis of the heavier elements. These two r-processes, however, do not contribute equally to the total abundance observed. The total isotopic abundance produced from both events was therefore calculated using equation refabund. Y(H+L) = fracY(H)+fY(L)f+1 <~belabund where Y(H) denotes the relative isotopic abundance produced in the high frequency event, Y(L) corresponds to the low freqeuncy event and f is the ratio of high event matter to low event matter produced. Having established reliable, fixed parameters, the network code was run using data files containing parameters such as the mass excess, neutron separation energy, β decay rates and neutron capture rates based around three different nuclear mass models. The mass models tested are the HFBCS model (Hartree-Fock BCS) derived from first principles, the ETFSI-Q model (Extended Thomas-Fermi with Strutinsky Integral including shell Quenching) known for its particular successes in the replication of Solar System

Detection of the Second r-process Peak Element Tellurium in Metal-poor Stars

NASA Astrophysics Data System (ADS)

Roederer, Ian U.; Lawler, James E.; Cowan, John J.; Beers, Timothy C.; Frebel, Anna; Ivans, Inese I.; Schatz, Hendrik; Sobeck, Jennifer S.; Sneden, Christopher

2012-03-01

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD +17 3248, HD 108317, and HD 128279. Tellurium (Te, Z = 52) is found at the second r-process peak (A ≈ 130) associated with the N = 82 neutron shell closure, and it has not been detected previously in Galactic halo stars. The derived tellurium abundances match the scaled solar system r-process distribution within the uncertainties, confirming the predicted second peak r-process residuals. These results suggest that tellurium is predominantly produced in the main component of the r-process, along with the rare earth elements. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO-8342 and GO-12268. Some of the data presented in this Letter were obtained from the Multimission Archive at the Space Telescope Science Institute (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These data are associated with programs GO-7348, GO-7402, GO-8197, and GO-9455.

Neutron Capture Rates and the r-Process Abundance Pattern in Shocked Neutrino-Driven Winds

NASA Astrophysics Data System (ADS)

Barringer, Daniel; Surman, Rebecca

2009-10-01

The r-process is an important process in nucleosynthesis in which nuclei will undergo rapid neutron captures. Models of the r-process require nuclear data such as neutron capture rates for thousands of individual nuclei, many of which lie far from stability. Among the potential sites for the r-process, and the one that we investigate, is the shocked neutrino-driven wind in core-collapse supernovae. Here we examine the importance of the neutron capture rates of specific, individual nuclei in the second r-process abundance peak occurring at A ˜ 130 for a range of parameterized neutrino-driven wind trajectories. Of specific interest are the nuclei whose capture rates affect the abundances of nuclei outside of the A ˜ 130 peak. We found that increasing the neutron capture rate for a number of nuclei including ^135In, ^132Sn, ^133Sb, ^137Sb, and ^136Te can produce changes in the resulting abundance pattern of up to 13%.

Systematic and statistical uncertainties in simulated r-process abundances due to uncertain nuclear masses

DOE PAGES

Surman, Rebecca; Mumpower, Matthew; McLaughlin, Gail

2017-02-27

Unknown nuclear masses are a major source of nuclear physics uncertainty for r-process nucleosynthesis calculations. Here we examine the systematic and statistical uncertainties that arise in r-process abundance predictions due to uncertainties in the masses of nuclear species on the neutron-rich side of stability. There is a long history of examining systematic uncertainties by the application of a variety of different mass models to r-process calculations. Here we expand upon such efforts by examining six DFT mass models, where we capture the full impact of each mass model by updating the other nuclear properties — including neutron capture rates, β-decaymore » lifetimes, and β-delayed neutron emission probabilities — that depend on the masses. Unlike systematic effects, statistical uncertainties in the r-process pattern have just begun to be explored. Here we apply a global Monte Carlo approach, starting from the latest FRDM masses and considering random mass variations within the FRDM rms error. Here, we find in each approach that uncertain nuclear masses produce dramatic uncertainties in calculated r-process yields, which can be reduced in upcoming experimental campaigns.« less

Systematic and statistical uncertainties in simulated r-process abundances due to uncertain nuclear masses

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

Surman, Rebecca; Mumpower, Matthew; McLaughlin, Gail

Unknown nuclear masses are a major source of nuclear physics uncertainty for r-process nucleosynthesis calculations. Here we examine the systematic and statistical uncertainties that arise in r-process abundance predictions due to uncertainties in the masses of nuclear species on the neutron-rich side of stability. There is a long history of examining systematic uncertainties by the application of a variety of different mass models to r-process calculations. Here we expand upon such efforts by examining six DFT mass models, where we capture the full impact of each mass model by updating the other nuclear properties — including neutron capture rates, β-decaymore » lifetimes, and β-delayed neutron emission probabilities — that depend on the masses. Unlike systematic effects, statistical uncertainties in the r-process pattern have just begun to be explored. Here we apply a global Monte Carlo approach, starting from the latest FRDM masses and considering random mass variations within the FRDM rms error. Here, we find in each approach that uncertain nuclear masses produce dramatic uncertainties in calculated r-process yields, which can be reduced in upcoming experimental campaigns.« less

The role of fission in Supernovae r-process nucleosynthesis

NASA Astrophysics Data System (ADS)

Otsuki, Kaori; Kajino, Toshitaka; Sumiyoshi, Kosuke; Ohta, Masahisa; Mathews, J. Grant

2001-10-01

The r-process elements are presumed to be produced in an explosive environment with short timescale at high entropy, like type-II supernova explosion. Intensive flux of free neutrons are absorbed successively by seed elements to form the nuclear reaction flow on extremely unstable nuclei on the neutron rich side. It would probe our knowledge of the properties of nulei far from the beta stability. It is also important in astronomy since this process forms the long-lived nuclear chronometers Thorium and Uranium that are utilised dating the age of the Milky Way. In our previous work, we showed that the succesful r-process nucleosynthesis can occure above young, hot protoneutron star. Although these long-lived heavy elements are produced comparable amounts to observation in several supernova models which we constructed, fission and alpha-decay were not included there. The fission products could play an important role in setting actinide yields which are used as cosmochronometers. In this talk, we report an infulence of fission on actinide yields and on estimate of Galactic age as well. We also discuss fission yields at lighter elements (Z ~ 50).

R -process Element Cosmic Rays from Neutron Star Mergers

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

Komiya, Yutaka; Shigeyama, Toshikazu

Neutron star mergers (NSMs) are one of the most plausible sources of r -process elements in the universe. Therefore, NSMs can also be a major source of ultra-heavy elements in cosmic rays. In this paper, we first estimate the contribution of r -process elements synthesized in NSMs to the ultra-heavy element cosmic rays (UHCRs) by calculating transport equations that take into account energy loss processes and spallations. We show that the flux of UHCRs accelerated by the NSMs themselves fluctuates by many orders of magnitude on a timescale of several million years and can overwhelm UHCRs accelerated by supernova remnantsmore » (SNRs) after an NSM takes place within a few kiloparsec from the solar system. Experiments with very long exposure times using meteorites as UHCR detectors can detect this fluctuation. As a consequence, we show that if NSMs are the primary source of UHCRs, future experiments using meteorites may be able to reveal the event history of NSMs in the solar vicinity. We also describe a possible difference in the abundance pattern and energy spectrum of UHCRs between NSM and SNR accelerations.« less

β-Decay Studies of r-Process Nuclei Using the Advanced Implantation Detector Array (AIDA)

NASA Astrophysics Data System (ADS)

Griffin, C. J.; Davinson, T.; Estrade, A.; Braga, D.; Burrows, I.; Coleman-Smith, P. J.; Grahn, T.; Grant, A.; Harkness-Brennan, L. J.; Kiss, G.; Kogimtzis, M.; Lazarus, I. H.; Letts, S. C.; Liu, Z.; Lorusso, G.; Matsui, K.; Nishimura, S.; Page, R. D.; Prydderch, M.; Phong, V. H.; Pucknell, V. F. E.; Rinta-Antila, S.; Roberts, O. J.; Seddon, D. A.; Simpson, J.; Thomas, S. L.; Woods, P. J.

Thought to produce around half of all isotopes heavier than iron, the r-process is a key mechanism for nucleosynthesis. However, a complete description of the r-process is still lacking and many unknowns remain. Experimental determination of β-decay half-lives and β-delayed neutron emission probabilities along the r-process path would help to facilitate a greater understanding of this process. The Advanced Implantation Detector Array (AIDA) represents the latest generation of silicon implantation detectors for β-decay studies with fast radioactive ion beams. Preliminary results from commissioning experiments demonstrate successful operation of AIDA and analysis of the data obtained during the first official AIDA experiments is now under-way.

Experimentally Determining β-Decay Intensities for 103,104Nb to Improve R-process Calculations

NASA Astrophysics Data System (ADS)

Gombas, J.; Deyoung, P. D.; Spyrou, A.; Dombos, A. C.; Lyons, S.; SuN Collaboration

2017-09-01

The rapid neutron capture process (r-process) is responsible for the formation of nuclei heavier than iron. This process is theorized to occur in supernovas and/or neutron star mergers. R-process calculations require the accurate knowledge of a significant amount of nuclear properties, the majority of which are not known experimentally. Nuclear masses, β-decay properties and neutron-capture reactions are all input ingredients into r-process models. This present study focuses on the β decay of 103Nb and 104Nb. The β decay of 103Nb and 104Nb, two nuclei found in the r-process, were observed at the NSCL using the Summing NaI (SuN) detector. An unstable beam implanted inside SuN. The γ rays were measured in coincidence with the emitted electrons. The β-decay intensity function was then extracted. The experimentally determined functions for 103Nb and 104Nb will be compared to predictions made by the Quasi Random Phase Approximation (QRPA) model. These theoretical calculations are used in astrophysical models of the r-process. This comparison will lead to a better understanding of the nuclear structure for 103Nb and 104Nb. A more dependable prediction of the formation of heavier nuclei birthed from supernovas or neutron star mergers can then be made. This material is based upon work supported by the National Science Foundation under Grant No. PHY-1613188 and PHY-1306074, and by the Hope College Department of Physics Guess Research Fund.

NEW NEUTRON-CAPTURE MEASUREMENTS IN 23 OPEN CLUSTERS. I. THE r -PROCESS

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

Overbeek, Jamie C.; Friel, Eileen D.; Jacobson, Heather R., E-mail: joverbee@indiana.edu

2016-06-20

Neutron-capture elements, those with Z > 35, are the least well understood in terms of nucleosynthesis and formation environments. The rapid neutron-capture, or r -process, elements are formed in the environments and/or remnants of massive stars, while the slow neutron-capture, or s -process, elements are primarily formed in low-mass AGB stars. These elements can provide much information about Galactic star formation and enrichment, but observational data are limited. We have assembled a sample of 68 stars in 23 open clusters that we use to probe abundance trends for six neutron-capture elements (Eu, Gd, Dy, Mo, Pr, and Nd) with clustermore » age and location in the disk of the Galaxy. In order to keep our analysis as homogeneous as possible, we use an automated synthesis fitting program, which also enables us to measure multiple (3–10) lines for each element. We find that the pure r -process elements (Eu, Gd, and Dy) have positive trends with increasing cluster age, while the mixed r - and s -process elements (Mo, Pr, and Nd) have insignificant trends consistent with zero. Pr, Nd, Eu, Gd, and Dy have similar, slight (although mostly statistically significant) gradients of ∼0.04 dex kpc{sup −1}. The mixed elements also appear to have nonlinear relationships with R {sub GC}.« less

Characterization of 16S rRNA Processing with Pre-30S Subunit Assembly Intermediates from E. coli.

PubMed

Smith, Brian A; Gupta, Neha; Denny, Kevin; Culver, Gloria M

2018-06-08

Ribosomal RNA (rRNA) is a major component of ribosomes and is fundamental to the process of translation. In bacteria, 16S rRNA is a component of the small ribosomal subunit and plays a critical role in mRNA decoding. rRNA maturation entails the removal of intervening spacer sequences contained within the pre-rRNA transcript by nucleolytic enzymes. Enzymatic activities involved in maturation of the 5'-end of 16S rRNA have been identified, but those involved in 3'-end maturation of 16S rRNA are more enigmatic. Here, we investigate molecular details of 16S rRNA maturation using purified in vivo-formed small subunit (SSU) assembly intermediates (pre-SSUs) from wild-type Escherichia coli that contain precursor 16S rRNA (17S rRNA). Upon incubation of pre-SSUs with E. coli S100 cell extracts or purified enzymes implicated in 16S rRNA processing, the 17S rRNA is processed into additional intermediates and mature 16S rRNA. These results illustrate that exonucleases RNase R, RNase II, PNPase, and RNase PH can process the 3'-end of pre-SSUs in vitro. However, the endonuclease YbeY did not exhibit nucleolytic activity with pre-SSUs under these conditions. Furthermore, these data demonstrate that multiple pathways facilitate 16S rRNA maturation with pre-SSUs in vitro, with the dominant pathways entailing complete processing of the 5'-end of 17S rRNA prior to 3'-end maturation or partial processing of the 5'-end with concomitant processing of the 3'-end. These results reveal the multifaceted nature of SSU biogenesis and suggest that E. coli may be able to escape inactivation of any one enzyme by using an existing complementary pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inhomogeneous chemical evolution of r-process elements

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

Wehmeyer, B., E-mail: benjamin.wehmeyer@unibas.ch; Thielemann, F.-K.; Pignatari, M.

2016-06-21

We report the results of a galactic chemical evolution (GCE) study for r-process- and alpha elements. For this work, we used the inhomogeneous GCE model ”ICE”, which allows to keep track of the galactic abundances of elements produced by different astrophysical sites. The main input parameters for this study were: a) The Neutron Star Merger (NSM) coalescence time scale, the probability of NSMs, and for the sub-class of ”magneto-rotationally driven Supernovae” (”Jet-SNe”), their occurence rate in comparison to ”standard” Supernovae (SNe).

Myristic Acid-Modified DA7R Peptide for Whole-Process Glioma-Targeted Drug Delivery.

PubMed

Ying, Man; Wang, Songli; Zhang, Mingfei; Wang, Ruifeng; Zhu, Hangchang; Ruan, Huitong; Ran, Danni; Chai, Zhilan; Wang, Xiaoyi; Lu, Weiyue

2018-06-13

The clinical treatment of aggressive glioma has been a great challenge, mainly because of the complexity of the glioma microenvironment and the existence of the blood-brain tumor barrier (BBTB)/blood-brain barrier (BBB), which severely hampers the effective accumulation of most therapeutic agents in the glioma region. Additionally, vasculogenic mimicry (VM), angiogenesis, and glioma stem cells (GSC) in malignant glioma also lead to the failure of clinical therapy. To address the aforementioned issues, a whole-process glioma-targeted drug delivery strategy was proposed. The D A7R peptide has effective BBTB-penetrating and notable glioma-, angiogenesis-, and VM-targeting abilities. Herein, we designed a myristic acid modified D A7R ligand (MC- D A7R), which combines tumor-homing D A7R with BBB-penetrable MC. MC- D A7R was then immobilized to PEGylated liposomes (MC- D A7R-LS) to form a whole-process glioma-targeting system. MC- D A7R-LS exhibited exceptional internalization in glioma, tumor neovascular, and brain capillary endothelial cells. Enhanced BBTB- and BBB-traversing efficiencies were also observed on MC- D A7R-LS. Ex vivo imaging on brain tumors also demonstrated the feasibility of MC- D A7R-LS in intracranial glioma-homing, whereas the immunofluorescence studies demonstrated its GSC and angiogenesis homing. Furthermore, doxorubicin-loaded MC- D A7R-LS accomplished a remarkable therapeutic outcome, as a result of a synergistic improvement on the glioma microenvironment. Our study highlights the potential of the MC-modified D A7R peptide as a great candidate for the whole-process glioma-targeted drug delivery.

The Galactic Chemical Evolution of r-Process Elements by Neutron Star Mergers

NASA Astrophysics Data System (ADS)

Komiya, Yutaka; Shigeyama, Toshikazu

Neutron star mergers (NSMs) are prime candidate sources of r-process elements in the universe but it have been said that NSMs cannot reproduce r-process elements on extremely metal-poor (EMP) stars. We revisit this problem using a new chemical evolution model with merger trees of galaxies. We consider (1) propagation of NSM ejecta of kilo-parsec scale due to its very large velocity and (2) star formation efficiency depending on the galaxy mass. In our model with these ingredients, NSMs can successfully reproduce the abundance distribution of EMP stars.

Space - A unique environment for process modeling R&D

NASA Technical Reports Server (NTRS)

Overfelt, Tony

1991-01-01

Process modeling, the application of advanced computational techniques to simulate real processes as they occur in regular use, e.g., welding, casting and semiconductor crystal growth, is discussed. Using the low-gravity environment of space will accelerate the technical validation of the procedures and enable extremely accurate determinations of the many necessary thermophysical properties. Attention is given to NASA's centers for the commercial development of space; joint ventures of universities, industries, and goverment agencies to study the unique attributes of space that offer potential for applied R&D and eventual commercial exploitation.

General Relativistic Effects on Neutrino-driven Winds from Young, Hot Neutron Stars and r-Process Nucleosynthesis

NASA Astrophysics Data System (ADS)

Otsuki, Kaori; Tagoshi, Hideyuki; Kajino, Toshitaka; Wanajo, Shin-ya

2000-04-01

Neutrino-driven winds from young hot neutron stars, which are formed by supernova explosions, are the most promising candidate site for r-process nucleosynthesis. We study general relativistic effects on this wind in Schwarzschild geometry in order to look for suitable conditions for successful r-process nucleosynthesis. It is quantitatively demonstrated that general relativistic effects play a significant role in increasing the entropy and decreasing the dynamic timescale of the neutrino-driven wind. Exploring the wide parameter region that determines the expansion dynamics of the wind, we find interesting physical conditions that lead to successful r-process nucleosynthesis. The conditions that we found are realized in a neutrino-driven wind with a very short dynamic timescale, τdyn~6 ms, and a relatively low entropy, S~140. We carry out α-process and r-process nucleosynthesis calculations on these conditions with our single network code, which includes over 3000 isotopes, and confirm quantitatively that the second and third r-process abundance peaks are produced in neutrino-driven winds.

Early chemo-dynamical evolution of dwarf galaxies deduced from enrichment of r-process elements

NASA Astrophysics Data System (ADS)

Hirai, Yutaka; Ishimaru, Yuhri; Saitoh, Takayuki R.; Fujii, Michiko S.; Hidaka, Jun; Kajino, Toshitaka

2017-04-01

The abundance of elements synthesized by the rapid neutron-capture process (r-process elements) of extremely metal-poor (EMP) stars in the Local Group galaxies gives us clues to clarify the early evolutionary history of the Milky Way halo. The Local Group dwarf galaxies would have similarly evolved with building blocks of the Milky Way halo. However, how the chemo-dynamical evolution of the building blocks affects the abundance of r-process elements is not yet clear. In this paper, we perform a series of simulations using dwarf galaxy models with various dynamical times and total mass, which determine star formation histories. We find that galaxies with dynamical times longer than 100 Myr have star formation rates less than 10-3 M⊙ yr-1 and slowly enrich metals in their early phase. These galaxies can explain the observed large scatters of r-process abundance in EMP stars in the Milky Way halo regardless of their total mass. On the other hand, the first neutron star merger appears at a higher metallicity in galaxies with a dynamical time shorter than typical neutron star merger times. The scatters of r-process elements mainly come from the inhomogeneity of the metals in the interstellar medium whereas the scatters of α-elements are mostly due to the difference in the yield of each supernova. Our results demonstrate that the future observations of r-process elements in EMP stars will be able to constrain the early chemo-dynamical evolution of the Local Group galaxies.

Phenopix: a R package to process digital images of a vegetation cover

NASA Astrophysics Data System (ADS)

Filippa, Gianluca; Cremonese, Edoardo; Migliavacca, Mirco; Galvagno, Marta; Morra di Cella, Umberto; Richardson, Andrew

2015-04-01

Plant phenology is a globally recognized indicator of the effects of climate change on the terrestrial biosphere. Accordingly, new tools to automatically track the seasonal development of a vegetation cover are becoming available and more and more deployed. Among them, near-continuous digital images are being collected in several networks in the US, Europe, Asia and Australia in a range of different ecosystems, including agricultural lands, deciduous and evergreen forests, and grasslands. The growing scientific interest in vegetation image analysis highlights the need of easy to use, flexible and standardized processing techniques. In this contribution we illustrate a new open source package called "phenopix" written in R language that allows to process images of a vegetation cover. The main features include: (i) define of one or more areas of interest on an image and process pixel information within them, (ii) compute vegetation indexes based on red green and blue channels, (iii) fit a curve to the seasonal trajectory of vegetation indexes and extract relevant dates (aka thresholds) on the seasonal trajectory; (iv) analyze image pixels separately to extract spatially explicit phenological information. The utilities of the package will be illustrated in detail for two subalpine sites, a grassland and a larch stand at about 2000 m in the Italian Western Alps. The phenopix package is a cost free and easy-to-use tool that allows to process digital images of a vegetation cover in a standardized, flexible and reproducible way. The software is available for download at the R forge web site (r-forge.r-project.org/projects/phenopix/).

Variance to mean ratio, R(t), for poisson processes on phylogenetic trees.

PubMed

Goldman, N

1994-09-01

The ratio of expected variance to mean, R(t), of numbers of DNA base substitutions for contemporary sequences related by a "star" phylogeny is widely seen as a measure of the adherence of the sequences' evolution to a Poisson process with a molecular clock, as predicted by the "neutral theory" of molecular evolution under certain conditions. A number of estimators of R(t) have been proposed, all predicted to have mean 1 and distributions based on the chi 2. Various genes have previously been analyzed and found to have values of R(t) far in excess of 1, calling into question important aspects of the neutral theory. In this paper, I use Monte Carlo simulation to show that the previously suggested means and distributions of estimators of R(t) are highly inaccurate. The analysis is applied to star phylogenies and to general phylogenetic trees, and well-known gene sequences are reanalyzed. For star phylogenies the results show that Kimura's estimators ("The Neutral Theory of Molecular Evolution," Cambridge Univ. Press, Cambridge, 1983) are unsatisfactory for statistical testing of R(t), but confirm the accuracy of Bulmer's correction factor (Genetics 123: 615-619, 1989). For all three nonstar phylogenies studied, attained values of all three estimators of R(t), although larger than 1, are within their true confidence limits under simple Poisson process models. This shows that lineage effects can be responsible for high estimates of R(t), restoring some limited confidence in the molecular clock and showing that the distinction between lineage and molecular clock effects is vital.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhomogeneous galactic chemical evolution of r-process elements

NASA Astrophysics Data System (ADS)

Wehmeyer, Benjamin

2018-01-01

Stars provide a fundamental contribution to the cosmic life cycle. Gas clouds form and collapse to stars, experiencing different evolutionary stages according to their properties like mass and metal content. Small stars like our Sun end their life as planetary nebulae, while more massive stars end their evolution with violent explosions like supernovae or hypernovae, leaving behind either a neutron star or a black hole. These compact objects may also merge, leading to a new ejection of material. Today the origin of the heaviest elements is still matter of debate. The relative contributions of the proposed sources of r-process elements (e.g., Supernovae, Neutron Star Mergers) in the early galaxy as well as in the Sun is one of the main uncertainties. We use the inhomogeneous chemical evolution tool “ICE” [1, 2] to study the role of some of the main parameters of the cosmic life cycle. With ICE's high resolution (≥ 20parsec/cell) runs, we are able to get converged simulations of the inhomogeneities in the early Galactic evolution stages, and of the observed scatter of r-process elements in metal-poor stars [3].[1] B. Wehmeyer, M. Pignatari, F.-K. Thielemann, 2015 MNRAS 452, 1970–1981[2] B. Wehmeyer, M. Pignatari, F.-K. Thielemann, 2016 AIPC 1743, 040009[3] I. Roederer et al., 2010 ApJ 724:975–993

r-Process nucleosynthesis from three-dimensional jet-driven core-collapse supernovae with magnetic misalignments

NASA Astrophysics Data System (ADS)

Halevi, Goni; Mösta, Philipp

2018-06-01

We investigate r-process nucleosynthesis in three-dimensional general relativistic magnetohydrodynamic simulations of jet-driven supernovae resulting from rapidly rotating, strongly magnetized core-collapse. We explore the effect of misaligning the pre-collapse magnetic field with respect to the rotation axis by performing four simulations: one aligned model and models with 15°, 30°, and 45° misalignments. The simulations we present employ a microphysical finite-temperature equation of state and a leakage scheme that captures the overall energetics and lepton number exchange due to post-bounce neutrino emission and absorption. We track the thermodynamic properties of the ejected material with Lagrangian tracer particles and analyse its composition with the nuclear reaction network SKYNET. By using different neutrino luminosities in post-processing the tracer data with SKYNET, we constrain the impact of uncertainties in neutrino luminosities. We find that, for the aligned model considered here, the use of an approximate leakage scheme results in neutrino luminosity uncertainties corresponding to a factor of 100-1000 uncertainty in the abundance of third peak r-process elements. Our results show that for misalignments of 30° or less, r-process elements are robustly produced as long as neutrino luminosities are reasonably low (≲ 5 × 1052 erg s-1). For a more extreme misalignment of 45°, we find the production of r-process elements beyond the second peak significantly reduced. We conclude that robust r-process nucleosynthesis in magnetorotational supernovae requires a progenitor stellar core with a large poloidal magnetic field component that is at least moderately (within ˜30°) aligned with the rotation axis.

A Stringent Limit on the Mass Production Rate of r-process Elements in the Milky Way

NASA Astrophysics Data System (ADS)

Macias, Phillip; Ramirez-Ruiz, Enrico

2018-06-01

We analyze data from several studies of metal-poor stars in the Milky Way, focusing individually on the main r-process elements (Eu) as well as the lighter neutron-capture element Sr, at the neutron-magic peak N = 50. Because these elements were injected in an explosion, we calculate the mass swept up when the blast wave first becomes radiative, yielding a lower limit for the dilution of such elements and hence a lower limit on the ejecta mass that is incorporated into the next generation of stars. Our study demonstrates that in order to explain the largest enhancements in [Eu/Fe] observed in stars at low [Fe/H] metallicities, individual r-process production events must synthesize a minimum of roughly 10‑3 M ⊙ of r-process material. This provides a critical constraint on galactic chemical evolution models. We also show independently that if the site of Mg production is the same as that of Eu, individual injection events must synthesize up to ∼10‑3 M ⊙ of r-process material. On the other hand, demanding that Sr traces Mg production results in r-process masses per event of ∼10‑5 M ⊙ . This suggests that the astrophysical sites responsible for the genesis of the main r-process elements need to operate at a drastically reduced rate when compared to standard core-collapse supernovae.

R&D on Composition and Processing of Titanium Aluminide Alloys for Turbine Engines

DTIC Science & Technology

1982-07-01

45433. AUTHORITY AFWAL ltr, 6 Feb 1987 THIS PAGE IS UNCLASSIFIED AFWAL-TR-82-4086 R&D ON COMPOSITION AND PROCESSING4 OF TITANIUM ALUMINIDE ALLOYS FOR...TR-82-4086- 4. TITLE (and Subitfle) S TYPE OF REPORT I PERIOO COVEREO R&D ON COMPOSITION AND PROCESSING OF Interim Technical Report TITANIUM ALUMINIDE ...ILLUSTRATIONS FICURE PACE 1 As-received titanium aluminide ingots supplied 9 by RMI. (a) S/N 20007; (b) left to right, S/N 20008, S/N 20009, S/N 20010

Solar r-process-constrained actinide production in neutrino-driven winds of supernovae

NASA Astrophysics Data System (ADS)

Goriely, S.; Janka, H.-Th.

2016-07-01

Long-lived radioactive nuclei play an important role as nucleo-cosmochronometers and as cosmic tracers of nucleosynthetic source activity. In particular, nuclei in the actinide region like thorium, uranium, and plutonium can testify to the enrichment of an environment by the still enigmatic astrophysical sources that are responsible for the production of neutron-rich nuclei by the rapid neutron-capture process (r-process). Supernovae and merging neutron-star (NS) or NS-black hole binaries are considered as most likely sources of the r-nuclei. But arguments in favour of one or the other or both are indirect and make use of assumptions; they are based on theoretical models with remaining simplifications and shortcomings. An unambiguous observational determination of a production event is still missing. In order to facilitate searches in this direction, e.g. by looking for radioactive tracers in stellar envelopes, the interstellar medium or terrestrial reservoirs, we provide improved theoretical estimates and corresponding uncertainty ranges for the actinide production (232Th, 235, 236, 238U, 237Np, 244Pu, and 247Cm) in neutrino-driven winds of core-collapse supernovae. Since state-of-the-art supernova models do not yield r-process viable conditions - but still lack, for example, the effects of strong magnetic fields - we base our investigation on a simple analytical, Newtonian, adiabatic and steady-state wind model and consider the superposition of a large number of contributing components, whose nucleosynthesis-relevant parameters (mass weight, entropy, expansion time-scale, and neutron excess) are constrained by the assumption that the integrated wind nucleosynthesis closely reproduces the Solar system distribution of r-process elements. We also test the influence of uncertain nuclear physics.

The Evolutionarily Conserved Protein LAS1 Is Required for Pre-rRNA Processing at Both Ends of ITS2

PubMed Central

Schillewaert, Stéphanie; Wacheul, Ludivine; Lhomme, Frédéric

2012-01-01

Ribosome synthesis entails the formation of mature rRNAs from long precursor molecules, following a complex pre-rRNA processing pathway. Why the generation of mature rRNA ends is so complicated is unclear. Nor is it understood how pre-rRNA processing is coordinated at distant sites on pre-rRNA molecules. Here we characterized, in budding yeast and human cells, the evolutionarily conserved protein Las1. We found that, in both species, Las1 is required to process ITS2, which separates the 5.8S and 25S/28S rRNAs. In yeast, Las1 is required for pre-rRNA processing at both ends of ITS2. It is required for Rrp6-dependent formation of the 5.8S rRNA 3′ end and for Rat1-dependent formation of the 25S rRNA 5′ end. We further show that the Rat1-Rai1 5′-3′ exoribonuclease (exoRNase) complex functionally connects processing at both ends of the 5.8S rRNA. We suggest that pre-rRNA processing is coordinated at both ends of 5.8S rRNA and both ends of ITS2, which are brought together by pre-rRNA folding, by an RNA processing complex. Consistently, we note the conspicuous presence of ∼7- or 8-nucleotide extensions on both ends of 5.8S rRNA precursors and at the 5′ end of pre-25S RNAs suggestive of a protected spacer fragment of similar length. PMID:22083961

Advanced LIGO constraints on neutron star mergers and r-process sites

DOE PAGES

Côté, Benoit; Belczynski, Krzysztof; Fryer, Chris L.; ...

2017-02-20

The role of compact binary mergers as the main production site of r-process elements is investigated by combining stellar abundances of Eu observed in the Milky Way, galactic chemical evolution (GCE) simulations, and binary population synthesis models, and gravitational wave measurements from Advanced LIGO. We compiled and reviewed seven recent GCE studies to extract the frequency of neutron star–neutron star (NS–NS) mergers that is needed in order to reproduce the observed [Eu/Fe] versus [Fe/H] relationship. We used our simple chemical evolution code to explore the impact of different analytical delay-time distribution functions for NS–NS mergers. We then combined our metallicity-dependent population synthesis models with our chemical evolution code to bring their predictions, for both NS–NS mergers and black hole–neutron star mergers, into a GCE context. Finally, we convolved our results with the cosmic star formation history to provide a direct comparison with current and upcoming Advanced LIGO measurements. When assuming that NS–NS mergers are the exclusive r-process sites, and that the ejected r-process mass per merger event is 0.01 Mmore » $${}_{\\odot }$$, the number of NS–NS mergers needed in GCE studies is about 10 times larger than what is predicted by standard population synthesis models. Here, these two distinct fields can only be consistent with each other when assuming optimistic rates, massive NS–NS merger ejecta, and low Fe yields for massive stars. For now, population synthesis models and GCE simulations are in agreement with the current upper limit (O1) established by Advanced LIGO during their first run of observations. Upcoming measurements will provide an important constraint on the actual local NS–NS merger rate, will provide valuable insights on the plausibility of the GCE requirement, and will help to define whether or not compact binary mergers can be the dominant source of r-process elements in the universe.« less

Galactic r-process enrichment by neutron star mergers in cosmological simulations of a Milky Way-mass galaxy

NASA Astrophysics Data System (ADS)

van de Voort, Freeke; Quataert, Eliot; Hopkins, Philip F.; Kereš, Dušan; Faucher-Giguère, Claude-André

2015-02-01

We quantify the stellar abundances of neutron-rich r-process nuclei in cosmological zoom-in simulations of a Milky Way-mass galaxy from the Feedback In Realistic Environments project. The galaxy is enriched with r-process elements by binary neutron star (NS) mergers and with iron and other metals by supernovae. These calculations include key hydrodynamic mixing processes not present in standard semi-analytic chemical evolution models, such as galactic winds and hydrodynamic flows associated with structure formation. We explore a range of models for the rate and delay time of NS mergers, intended to roughly bracket the wide range of models consistent with current observational constraints. We show that NS mergers can produce [r-process/Fe] abundance ratios and scatter that appear reasonably consistent with observational constraints. At low metallicity, [Fe/H] ≲ -2, we predict there is a wide range of stellar r-process abundance ratios, with both supersolar and subsolar abundances. Low-metallicity stars or stars that are outliers in their r-process abundance ratios are, on average, formed at high redshift and located at large galactocentric radius. Because NS mergers are rare, our results are not fully converged with respect to resolution, particularly at low metallicity. However, the uncertain rate and delay time distribution of NS mergers introduce an uncertainty in the r-process abundances comparable to that due to finite numerical resolution. Overall, our results are consistent with NS mergers being the source of most of the r-process nuclei in the Universe.

Beta-decay half-lives for short neutron rich nuclei involved into the r-process

NASA Astrophysics Data System (ADS)

Panov, I.; Lutostansky, Yu; Thielemann, F.-K.

2018-01-01

The beta-strength function model based on Finite Fermi-Systems Theory is applied for calculations of the beta-decay half-lives for short neutron rich nuclei involved into the r- process. It is shown that the accuracy of beta-decay half-lives of short-lived neutron-rich nuclei is improving with increasing neutron excess and can be used for modeling of nucleosynthesis of heavy nuclei in the r-process.

DETECTION OF ELEMENTS AT ALL THREE r-PROCESS PEAKS IN THE METAL-POOR STAR HD 160617

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

Roederer, Ian U.; Lawler, James E., E-mail: iur@obs.carnegiescience.edu, E-mail: jelawler@wisc.edu

2012-05-01

We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium, osmium, iridium, and platinum, which have been detected previously. Absorption lines of these elements are found in archive observations made with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. We present up-to-date absolute atomic transition probabilities and complete line component patterns for these elements. Additional archival spectra of this star from several ground-based instruments allow us to derive abundancesmore » or upper limits of 45 elements in HD 160617, including 27 elements produced by neutron-capture reactions. The average abundances of the elements at the three r-process peaks are similar to the predicted solar system r-process residuals when scaled to the abundances in the rare earth element domain. This result for arsenic and selenium may be surprising in light of predictions that the production of the lightest r-process elements generally should be decoupled from the heavier r-process elements.« less

Using r-process enhanced galaxies to estimate the neutron star merger rate at high redshift

NASA Astrophysics Data System (ADS)

Roederer, Ian

2018-01-01

The rapid neutron-capture process, or r-process, is one of the fundamental ways that stars produce heavy elements. I describe a new approach that uses the existence of r-process enhanced galaxies, like the recently discovered ultra-faint dwarf galaxy Reticulum II, to derive a rate for neutron star mergers at high redshift. This method relies on three assertions. First, several lines of reasoning point to neutron star mergers as a rare yet prolific producer of r-process elements, and one merger event is capable of enriching most of the stars in a low-mass dwarf galaxy. Second, the Local Group is cosmologically representative of the halo mass function at the mass scales of low-luminosity dwarf galaxies, and the volume that their progenitors spanned at high redshifts can be estimated from simulations. Third, many of these dwarf galaxies are extremely old, and the metals found in their stars today date from the earliest times at high redshift. These galaxies occupy a quantifiable volume of the Universe, from which the frequency of r-process enhanced galaxies can be estimated. This frequency may be interpreted as lower limit to the neutron star merger rate at a redshift (z ~ 5-10) that is much higher than is accessible to gravitational wave observatories. I will present a proof of concept demonstration using medium-resolution multi-object spectroscopy from the Michigan/Magellan Fiber System (M2FS) to recover the known r-process galaxy Reticulum II, and I will discuss future plans to apply this method to other Local Group dwarf galaxies.

Chemo-Dynamical Evolution of r-process Elements in the Local Group Galaxies

NASA Astrophysics Data System (ADS)

Hirai, Yutaka; Ishimaru, Yuhri; Saitoh, Takayuki R.; Fujii, Michiko S.; Hidaka, Jun; Kajino, Toshitaka

The astrophysical site(s) of r-process is not yet identified over half a century. Astronomical high dispersion observations have shown that extremely metal-poor (EMP) stars in the Milky Way (MW) halo have large star-to-star dispersions in the abundance of r-process elements. Binary neutron star mergers (NSMs) are one of the most promising sites of r-process. However, several studies suggested that it is difficult to reproduce the dispersions by NSMs due to their long merger times and low rates. In this study, we performed a series of N-body/smoothed particle hydrodynamic simulations of dwarf galaxies. We show that NSMs can explain the dispersions with long merger times (˜100 Myr). We find that the metallicity of our simulated galaxies does not correlate with time in their early phase due to slow chemical enrichment. This slow chemical enrichment produces [Eu/Fe] distribution which is consistent with the observation. Our results suggest that stars in the MW halo formed with a low star formation rate of less than 10 - 3M ⊙ yr-1, which is common for typical dwarf galaxies in the MW. Our simulations support the scenario that early enrichment of the MW halo occurred in the framework of hierarchical structure formation.

The Link Between Rare-Earth Peak Formation and the Astrophysical Site of the R Process

DOE PAGES

Mumpower, Matthew R.; McLaughlin, Gail C.; Surman, Rebecca; ...

2016-12-20

The primary astrophysical source of the rare-earth elements is the rapid neutron capture process (r process). The rare-earth peak that is seen in the solar r-process residuals has been proposed to originate as a pile-up of nuclei during the end of the r process. Here, we introduce a new method utilizing Monte Carlo studies of nuclear masses in the rare-earth region, that includes self-consistently adjusting β-decay rates and neutron capture rates, to find the mass surfaces necessary for the formation of the rare-earth peak. We demonstrate our method with two types of astrophysical scenario, one corresponding to conditions typical ofmore » hot winds from core-collapse supernovae and stellar-mass accretion disks, and one corresponding to conditions typical of the ejection of the material from the tidal tails of neutron star mergers. In each type of astrophysical condition, this method successfully locates a region of enhanced stability in the mass surface that is responsible for the rare-earth peak. Finally, for each scenario, we find that the change in the mass surface has qualitatively different features, thus future measurements can shed light on the type of environment in which the r process occurred.« less

The Link Between Rare-Earth Peak Formation and the Astrophysical Site of the R Process

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

Mumpower, Matthew R.; McLaughlin, Gail C.; Surman, Rebecca

The primary astrophysical source of the rare-earth elements is the rapid neutron capture process (r process). The rare-earth peak that is seen in the solar r-process residuals has been proposed to originate as a pile-up of nuclei during the end of the r process. Here, we introduce a new method utilizing Monte Carlo studies of nuclear masses in the rare-earth region, that includes self-consistently adjusting β-decay rates and neutron capture rates, to find the mass surfaces necessary for the formation of the rare-earth peak. We demonstrate our method with two types of astrophysical scenario, one corresponding to conditions typical ofmore » hot winds from core-collapse supernovae and stellar-mass accretion disks, and one corresponding to conditions typical of the ejection of the material from the tidal tails of neutron star mergers. In each type of astrophysical condition, this method successfully locates a region of enhanced stability in the mass surface that is responsible for the rare-earth peak. Finally, for each scenario, we find that the change in the mass surface has qualitatively different features, thus future measurements can shed light on the type of environment in which the r process occurred.« less

THE LINK BETWEEN RARE-EARTH PEAK FORMATION AND THE ASTROPHYSICAL SITE OF THE R PROCESS

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

Mumpower, Matthew R.; McLaughlin, Gail C.; Surman, Rebecca

The primary astrophysical source of the rare-earth elements is the rapid neutron capture process ( r process). The rare-earth peak that is seen in the solar r -process residuals has been proposed to originate as a pile-up of nuclei during the end of the r process. We introduce a new method utilizing Monte Carlo studies of nuclear masses in the rare-earth region, that includes self-consistently adjusting β -decay rates and neutron capture rates, to find the mass surfaces necessary for the formation of the rare-earth peak. We demonstrate our method with two types of astrophysical scenario, one corresponding to conditionsmore » typical of hot winds from core-collapse supernovae and stellar-mass accretion disks, and one corresponding to conditions typical of the ejection of the material from the tidal tails of neutron star mergers. In each type of astrophysical condition, this method successfully locates a region of enhanced stability in the mass surface that is responsible for the rare-earth peak. For each scenario, we find that the change in the mass surface has qualitatively different features, thus future measurements can shed light on the type of environment in which the r process occurred.« less

The AMBRE Project: r-process element abundances in the Milky Way thin and thick discs

NASA Astrophysics Data System (ADS)

Guiglion, Guillaume; de Laverny, Patrick; Recio-Blanco, Alejandra; Worley, C. Clare

2018-04-01

Chemical evolution of r-process elements in the Milky Way disc is still a matter of debate. We took advantage of high resolution HARPS spectra from the ESO archive in order to derive precise chemical abundances of 3 r-process elements Eu, Dy & Gd for a sample of 4 355 FGK Milky Way stars. The chemical analysis has been performed thanks to the automatic optimization pipeline GAUGUIN. Based on the [α/Fe] ratio, we chemically characterized the thin and the thick discs, and present here results of these 3 r-process element abundances in both discs. We found an unexpected Gadolinium and Dysprosium enrichment in the thick disc stars compared to Europium, while these three elements track well each other in the thin disc.

Neutrino-heated winds from millisecond protomagnetars as sources of the weak r-process

NASA Astrophysics Data System (ADS)

Vlasov, Andrey D.; Metzger, Brian D.; Lippuner, Jonas; Roberts, Luke F.; Thompson, Todd A.

2017-06-01

We explore heavy element nucleosynthesis in neutrino-driven winds from rapidly rotating, strongly magnetized protoneutron stars ('millisecond protomagnetars') for which the magnetic dipole is aligned with the rotation axis, and the field is assumed to be a static force-free configuration. We process the protomagnetar wind trajectories calculated by Vlasov, Metzger & Thompson through the r-process nuclear reaction network SkyNet using contemporary models for the evolution of the wind electron fraction during the protoneutron star cooling phase. Although we do not find a successful second or third-peak r-process for any rotation period P, we show that protomagnetars with P ˜ 1-5 ms produce heavy element abundance distributions that extend to higher nuclear mass number than from otherwise equivalent spherical winds (with the mass fractions of some elements enhanced by factors of ≳100-1000). The heaviest elements are synthesized by outflows emerging along flux tubes that graze the closed zone and pass near the equatorial plane outside the light cylinder. Due to dependence of the nucleosynthesis pattern on the magnetic field strength and rotation rate of the protoneutron star, natural variations in these quantities between core collapse events could contribute to the observed diversity of the abundances of weak r-process nuclei in metal-poor stars. Further diversity, including possibly even a successful third-peak r-process, could be achieved for misaligned rotators with non-zero magnetic inclination with respect to the rotation axis. If protomagnetars are central engines for GRBs, their relativistic jets should contain a high-mass fraction of heavy nuclei of characteristic mass number \\bar{A}≈ 100, providing a possible source for ultrahigh energy cosmic rays comprised of heavy nuclei with an energy spectrum that extends beyond the nominal Grezin-Zatsepin-Kuzmin cut-off for protons or iron nuclei.

RNase MRP is required for entry of 35S precursor rRNA into the canonical processing pathway.

PubMed

Lindahl, Lasse; Bommankanti, Ananth; Li, Xing; Hayden, Lauren; Jones, Adrienne; Khan, Miriam; Oni, Tolulope; Zengel, Janice M

2009-07-01

RNase MRP is a nucleolar RNA-protein enzyme that participates in the processing of rRNA during ribosome biogenesis. Previous experiments suggested that RNase MRP makes a nonessential cleavage in the first internal transcribed spacer. Here we report experiments with new temperature-sensitive RNase MRP mutants in Saccharomyces cerevisiae that show that the abundance of all early intermediates in the processing pathway is severely reduced upon inactivation of RNase MRP. Transcription of rRNA continues unabated as determined by RNA polymerase run-on transcription, but the precursor rRNA transcript does not accumulate, and appears to be unstable. Taken together, these observations suggest that inactivation of RNase MRP blocks cleavage at sites A0, A1, A2, and A3, which in turn, prevents precursor rRNA from entering the canonical processing pathway (35S > 20S + 27S > 18S + 25S + 5.8S rRNA). Nevertheless, at least some cleavage at the processing site in the second internal transcribed spacer takes place to form an unusual 24S intermediate, suggesting that cleavage at C2 is not blocked. Furthermore, the long form of 5.8S rRNA is made in the absence of RNase MRP activity, but only in the presence of Xrn1p (exonuclease 1), an enzyme not required for the canonical pathway. We conclude that RNase MRP is a key enzyme for initiating the canonical processing of precursor rRNA transcripts, but alternative pathway(s) might provide a backup for production of small amounts of rRNA.

The influence of collective neutrino oscillations on a supernova r process

NASA Astrophysics Data System (ADS)

Duan, Huaiyu; Friedland, Alexander; McLaughlin, Gail C.; Surman, Rebecca

2011-03-01

Recently, it has been demonstrated that neutrinos in a supernova oscillate collectively. This process occurs much deeper than the conventional matter-induced Mikheyev-Smirnov-Wolfenstein effect and hence may have an impact on nucleosynthesis. In this paper we explore the effects of collective neutrino oscillations on the r-process, using representative late-time neutrino spectra and outflow models. We find that accurate modeling of the collective oscillations is essential for this analysis. As an illustration, the often-used 'single-angle' approximation makes grossly inaccurate predictions for the yields in our setup. With the proper multiangle treatment, the effect of the oscillations is found to be less dramatic, but still significant. Since the oscillation patterns are sensitive to the details of the emitted fluxes and the sign of the neutrino mass hierarchy, so are the r-process yields. The magnitude of the effect also depends sensitively on the astrophysical conditions—in particular on the interplay between the time when nuclei begin to exist in significant numbers and the time when the collective oscillation begins. A more definitive understanding of the astrophysical conditions, and accurate modeling of the collective oscillations for those conditions, is necessary.

The cytoplasmic mRNA degradation factor Pat1 is required for rRNA processing

PubMed Central

Muppavarapu, Mridula; Huch, Susanne; Nissan, Tracy

2016-01-01

ABSTRACT Pat1 is a key cytoplasmic mRNA degradation factor, the loss of which severely increases mRNA half-lives. Several recent studies have shown that Pat1 can enter the nucleus and can shuttle between the nucleus and the cytoplasm. As a result, many nuclear roles have been proposed for Pat1. In this study, we analyzed four previously suggested nuclear roles of Pat1 and show that Pat1 is not required for efficient pre-mRNA splicing or pre-mRNA decay in yeast. However, lack of Pat1 results in accumulation of pre-rRNA processing intermediates. Intriguingly, we identified a novel genetic relationship between Pat1 and the rRNA decay machinery, specifically the exosome and the TRAMP complex. While the pre-rRNA processing intermediates that accumulate in the pat1 deletion mutant are, at least to some extent, recognized as aberrant by the rRNA degradation machinery, it is unlikely that these accumulations are the cause of their synthetic sick relationship. Here, we show that the dysregulation of the levels of mRNAs related to ribosome biogenesis could be the cause of the accumulation of the pre-rRNA processing intermediates. Although our results support a role for Pat1 in transcription, they nevertheless suggest that the primary cause of the dysregulated mRNA levels is most likely due to Pat1's role in mRNA decapping and mRNA degradation. PMID:26918764

The cytoplasmic mRNA degradation factor Pat1 is required for rRNA processing.

PubMed

Muppavarapu, Mridula; Huch, Susanne; Nissan, Tracy

2016-01-01

Pat1 is a key cytoplasmic mRNA degradation factor, the loss of which severely increases mRNA half-lives. Several recent studies have shown that Pat1 can enter the nucleus and can shuttle between the nucleus and the cytoplasm. As a result, many nuclear roles have been proposed for Pat1. In this study, we analyzed four previously suggested nuclear roles of Pat1 and show that Pat1 is not required for efficient pre-mRNA splicing or pre-mRNA decay in yeast. However, lack of Pat1 results in accumulation of pre-rRNA processing intermediates. Intriguingly, we identified a novel genetic relationship between Pat1 and the rRNA decay machinery, specifically the exosome and the TRAMP complex. While the pre-rRNA processing intermediates that accumulate in the pat1 deletion mutant are, at least to some extent, recognized as aberrant by the rRNA degradation machinery, it is unlikely that these accumulations are the cause of their synthetic sick relationship. Here, we show that the dysregulation of the levels of mRNAs related to ribosome biogenesis could be the cause of the accumulation of the pre-rRNA processing intermediates. Although our results support a role for Pat1 in transcription, they nevertheless suggest that the primary cause of the dysregulated mRNA levels is most likely due to Pat1's role in mRNA decapping and mRNA degradation.

A real-time GNSS-R system based on software-defined radio and graphics processing units

NASA Astrophysics Data System (ADS)

Hobiger, Thomas; Amagai, Jun; Aida, Masanori; Narita, Hideki

2012-04-01

Reflected signals of the Global Navigation Satellite System (GNSS) from the sea or land surface can be utilized to deduce and monitor physical and geophysical parameters of the reflecting area. Unlike most other remote sensing techniques, GNSS-Reflectometry (GNSS-R) operates as a passive radar that takes advantage from the increasing number of navigation satellites that broadcast their L-band signals. Thereby, most of the GNSS-R receiver architectures are based on dedicated hardware solutions. Software-defined radio (SDR) technology has advanced in the recent years and enabled signal processing in real-time, which makes it an ideal candidate for the realization of a flexible GNSS-R system. Additionally, modern commodity graphic cards, which offer massive parallel computing performances, allow to handle the whole signal processing chain without interfering with the PC's CPU. Thus, this paper describes a GNSS-R system which has been developed on the principles of software-defined radio supported by General Purpose Graphics Processing Units (GPGPUs), and presents results from initial field tests which confirm the anticipated capability of the system.

RNomics in Archaea reveals a further link between splicing of archaeal introns and rRNA processing

PubMed Central

Tang, Thean Hock; Rozhdestvensky, Timofey S.; d’Orval, Béatrice Clouet; Bortolin, Marie-Line; Huber, Harald; Charpentier, Bruno; Branlant, Christiane; Bachellerie, Jean-Pierre; Brosius, Jürgen; Hüttenhofer, Alexander

2002-01-01

The bulge–helix–bulge (BHB) motif recognised by the archaeal splicing endonuclease is also found in the long processing stems of archaeal rRNA precursors in which it is cleaved to generate pre-16S and pre-23S rRNAs. We show that in two species, Archaeoglobus fulgidus and Sulfolobus solfataricus, representatives from the two major archaeal kingdoms Euryarchaeota and Crenarchaeota, respectively, the pre-rRNA spacers cleaved at the BHB motifs surrounding pre-16S and pre-23S rRNAs subsequently become ligated. In addition, we present evidence that this is accompanied by circularisation of ribosomal pre-16S and pre-23S rRNAs in both species. These data reveal a further link between intron splicing and pre-rRNA processing in Archaea, which might reflect a common evolutionary origin of the two processes. One spliced RNA species designated 16S-D RNA, resulting from religation at the BHB motif of 16S pre-rRNA, is a highly abundant and stable RNA which folds into a three-stem structure interrupted by two single-stranded regions as assessed by chemical probing. It spans a region of the pre-rRNA 5′ external transcribed spacer exhibiting a highly conserved folding pattern in Archaea. Surprisingly, 16S-D RNA contains structural motifs found in archaeal C/D box small RNAs and binds to the L7Ae protein, a core component of archaeal C/D box RNPs. This supports the notion that it might have an important but still unknown role in pre-rRNA biogenesis or might even target RNA molecules other than rRNA. PMID:11842103

Salinity inhibits post transcriptional processing of chloroplast 16S rRNA in shoot cultures of jojoba (Simmondsia chinesis).

PubMed

Mizrahi-Aviv, Ela; Mills, David; Benzioni, Aliza; Bar-Zvi, Dudy

2005-03-01

Chloroplast metabolism is rapidly affected by salt stress. Photosynthesis is one of the first processes known to be affected by salinity. Here, we report that salinity inhibits chloroplast post-transcriptional RNA processing. A differentially expressed 680-bp cDNA, containing the 3' sequence of 16S rRNA, transcribed intergenic spacer, exon 1 and intron of tRNA(Ile), was isolated by differential display reverse transcriptase PCR from salt-grown jojoba (Simmondsia chinesis) shoot cultures. Northern blot analysis indicated that although most rRNA appears to be fully processed, partially processed chloroplast 16S rRNA accumulates in salt-grown cultures. Thus, salinity appears to decrease the processing of the rrn transcript. The possible effect of this decreased processing on physiological processes is, as yet, unknown.

Processing of double-R-loops in (CAG)·(CTG) and C9orf72 (GGGGCC)·(GGCCCC) repeats causes instability

PubMed Central

Reddy, Kaalak; Schmidt, Monika H.M.; Geist, Jaimie M.; Thakkar, Neha P.; Panigrahi, Gagan B.; Wang, Yuh-Hwa; Pearson, Christopher E.

2014-01-01

R-loops, transcriptionally-induced RNA:DNA hybrids, occurring at repeat tracts (CTG)n, (CAG)n, (CGG)n, (CCG)n and (GAA)n, are associated with diseases including myotonic dystrophy, Huntington's disease, fragile X and Friedreich's ataxia. Many of these repeats are bidirectionally transcribed, allowing for single- and double-R-loop configurations, where either or both DNA strands may be RNA-bound. R-loops can trigger repeat instability at (CTG)·(CAG) repeats, but the mechanism of this is unclear. We demonstrate R-loop-mediated instability through processing of R-loops by HeLa and human neuron-like cell extracts. Double-R-loops induced greater instability than single-R-loops. Pre-treatment with RNase H only partially suppressed instability, supporting a model in which R-loops directly generate instability by aberrant processing, or via slipped-DNA formation upon RNA removal and its subsequent aberrant processing. Slipped-DNAs were observed to form following removal of the RNA from R-loops. Since transcriptionally-induced R-loops can occur in the absence of DNA replication, R-loop processing may be a source of repeat instability in the brain. Double-R-loop formation and processing to instability was extended to the expanded C9orf72 (GGGGCC)·(GGCCCC) repeats, known to cause amyotrophic lateral sclerosis and frontotemporal dementia, providing the first suggestion through which these repeats may become unstable. These findings provide a mechanistic basis for R-loop-mediated instability at disease-associated repeats. PMID:25147206

Impact of Delayed Whole Blood Processing Time on Plasma Levels of miR-1 and miR-423-5p up to 24 Hours.

PubMed

Borges, Danielle Pazzotti; Cunha-Neto, Edecio; Bocchi, Edimar A; Rigaud, Vagner Oliveira Carvalho

2018-03-21

Circulating cell-free miRNAs hold great promise as a new class of biomarkers due to their high stability in body fluids and association with disease stages. However, even using sensitive and specific methods, technical challenges are associated with miRNA analysis in body fluids. A major source of variation in plasma and serum is the potential cell-derived miRNA contamination from hemolysis. To evaluate the effect of the delayed whole blood processing time on the concentrations of miR-1 and -423-5p. Ten blood samples were incubated for 0, 3 and 24 hours at room temperature prior processing into plasma. For each time point, hemolysis was assessed in plasma by UV spectrophotometry at 414nm wavelength (λ414). Circulating levels of miR-1 and -423-5p were measured by RT-qPCR; miR-23a and -451 were also analyzed as controls. A significant hemolysis was observed only after 24h (λ414 0.3±0.02, p<0.001). However, only small changes in miR-1 and -423-5p levels were observed up to 24h of storage at room temperature (Ct 31.5±0.5 to 31.8±0.6for miR-1, p=0.989; and 29.01±0.3 to 29.04±0.3, p=0.614 for -423-5p). No correlation was observed between hemolysis and levels of miR-1 and -423-5p. Our data indicate the storage of whole blood samples at room temperature for up to 24h prior their processing into plasma does not appear to have a significant impact on miR-1 and -423-5p concentrations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The r-Process in the Neutrino Winds of Core-Collapse Supernovae and U-Th Cosmochronology

NASA Astrophysics Data System (ADS)

Wanajo, Shinya; Itoh, Naoki; Ishimaru, Yuhri; Nozawa, Satoshi; Beers, Timothy C.

2002-10-01

The discovery of the second highly r-process-enhanced, extremely metal poor star, CS 31082-001 ([Fe/H]=-2.9) has provided a powerful new tool for age determination by virtue of the detection and measurement of the radioactive species uranium and thorium. Because the half-life of 238U is one-third that of 232Th, the U-Th pair can, in principle, provide a far more precise cosmochronometer than the Th-Eu pair that has been used in previous investigations. In the application of this chronometer, the age of (the progenitor of) CS 31082-001 can be regarded as the minimum age of the Galaxy, and hence of the universe. One of the serious limitations of this approach, however, is that predictions of the production ratio of U and Th have not been made in the context of a realistic astrophysical model of the r-process. We have endeavored to produce such a model, based on the ``neutrino winds'' that are expected to arise from the nascent neutron star of a core-collapse supernova. In this model, the proto-neutron star mass and the (asymptotic) neutrino sphere radius are assumed to be 2.0 Msolar and 10 km, respectively. Recent hydrodynamic studies indicate that there may exist difficulties in obtaining such a compact (massive and/or small in radius) remnant. Nevertheless, we utilize this set of parameter choices since previous work suggests that the third r-process peak (and thus U and Th) is hardly reached when one adopts a less compact proto-neutron star in the framework of the neutrino-wind scenario. The temperature and density histories of the material involved in the neutron-capture processes are obtained with the assumption of a steady flow of the neutrino-powered winds, with general relativistic effects taken into account. The electron fraction is taken to be a free parameter, constant with time. The r-process nucleosynthesis in these trajectories is calculated with a nuclear reaction network code including actinides up to Z=100. The mass-integrated r-process yields

The role of fission on neutron star mergers and its impact on the r-process peaks

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

Eichler, M., E-mail: marius.eichler@unibas.ch; Thielemann, F.-K.; Arcones, A.

2016-06-21

The comparison between observational abundance features and those obtained from nucleosynthesis predictions of stellar evolution and/or explosion simulations can scrutinize two aspects: (a) the conditions in the astrophysical production site and (b) the quality of the nuclear physics input utilized. Here we test the abundance features of r-process nucleosynthesis calculations using four different fission fragment distribution models. Furthermore, we explore the origin of a shift in the third r-process peak position in comparison with the solar r-process abundances which has been noticed in a number of merger nucleosynthesis predictions. We show that this shift occurs during the r-process freeze-out whenmore » neutron captures and β-decays compete and an (n,γ)-(γ,n) equilibrium is not maintained anymore. During this phase neutrons originate mainly from fission of material above A = 240. We also investigate the role of β-decay half-lives from recent theoretical advances, which lead either to a smaller amount of fissioning nuclei during freeze-out or a faster (and thus earlier) release of fission neutrons, which can (partially) prevent this shift and has an impact on the second and rare-earth peak as well.« less

On the impact of neutron star binaries' natal-kick distribution on the Galactic r-process enrichment

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Côté, Benoit

2017-11-01

We study the impact of the neutron star binaries' (NSBs) natal-kick distribution on the galactic r-process enrichment. We model the growth of a Milky Way type halo based on N-body simulation results and its star formation history based on multi-epoch abundance matching techniques. We consider that the NSBs that merge well beyond the galaxy's effective radius (>2 × Reff) do not contribute to the galactic r-process enrichment. Assuming a power-law delay-time distribution (DTD) function (∝t-1) with tmin = 30 Myr for binaries' coalescence time-scales and an exponential profile for their natal-kick distribution with an average value of 180 km s-1, we show that up to ˜ 40 per cent of all formed NSBs do not contribute to the r-process enrichment by z = 0, either because they merge far from the galaxy at a given redshift (up to ˜ 25 per cent) or have not yet merged by today (˜ 15 per cent). Our result is largely insensitive to the details of the DTD function. Assuming a constant coalescence time-scale of 100 Myr well approximates the adopted DTD although with 30 per cent of the NSBs ending up not contributing to the r-process enrichment. Our results, although rather dependent on the adopted natal-kick distribution, represent the first step towards estimating the impact of natal kicks and DTD functions on the r-process enrichment of galaxies that would need to be incorporated in the hydrodynamical simulations.

Formation of Globular Clusters with Internal Abundance Spreads in r-Process Elements: Strong Evidence for Prolonged Star Formation

NASA Astrophysics Data System (ADS)

Bekki, Kenji; Tsujimoto, Takuji

2017-07-01

Several globular clusters (GCs) in the Galaxy are observed to show internal abundance spreads in r-process elements (e.g., Eu). We propose a new scenario that explains the origin of these GCs (e.g., M5 and M15). In this scenario, stars with no/little abundance variations first form from a massive molecular cloud (MC). After all of the remaining gas of the MC is expelled by numerous supernovae, gas ejected from asymptotic giant branch stars can be accumulated in the central region of the GC to form a high-density intracluster medium (ICM). Merging of neutron stars then occurs to eject r-process elements, which can be efficiently trapped in and subsequently mixed with the ICM. New stars formed from the ICM can have r-process abundances that are quite different from those of earlier generations of stars within the GC. This scenario can explain both (I) why r-process elements can be trapped within GCs and (II) why GCs with internal abundance spreads in r-process elements do not show [Fe/H] spreads. Our model shows (I) that a large fraction of Eu-rich stars can be seen in Na-enhanced stellar populations of GCs, as observed in M15, and (II) why most of the Galactic GCs do not exhibit such internal abundance spreads. Our model demonstrates that the observed internal spreads of r-process elements in GCs provide strong evidence for prolonged star formation (˜108 yr).

Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis

PubMed Central

Brennecka, Gregory A.; Borg, Lars E.; Wadhwa, Meenakshi

2013-01-01

The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a distinct isotopic signature. We show that the isotopic compositions of elements spanning a large mass range in the earliest formed solids in our Solar System, calcium–aluminum-rich inclusions (CAIs), are uniform, and yet distinct from the average Solar System composition. Relative to younger objects in the Solar System, CAIs contain positive r-process anomalies in isotopes A < 140 and negative r-process anomalies in isotopes A > 140. This fundamental difference in the isotopic character of CAIs around mass 140 necessitates (i) the existence of multiple sources for r-process nucleosynthesis and (ii) the injection of supernova material into a reservoir untapped by CAIs. A scenario of late supernova injection into the protoplanetary disk is consistent with formation of our Solar System in an active star-forming region of the galaxy. PMID:24101483

Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis.

PubMed

Brennecka, Gregory A; Borg, Lars E; Wadhwa, Meenakshi

2013-10-22

The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a distinct isotopic signature. We show that the isotopic compositions of elements spanning a large mass range in the earliest formed solids in our Solar System, calcium-aluminum-rich inclusions (CAIs), are uniform, and yet distinct from the average Solar System composition. Relative to younger objects in the Solar System, CAIs contain positive r-process anomalies in isotopes A < 140 and negative r-process anomalies in isotopes A > 140. This fundamental difference in the isotopic character of CAIs around mass 140 necessitates (i) the existence of multiple sources for r-process nucleosynthesis and (ii) the injection of supernova material into a reservoir untapped by CAIs. A scenario of late supernova injection into the protoplanetary disk is consistent with formation of our Solar System in an active star-forming region of the galaxy.

Building bridges from process R&D: from a customer-supplier relationship to full partnership.

PubMed

Federsel

2000-08-01

A new and forward-looking way of running process R&D is introduced that integrates this core business in an efficient manner into the network of activities in different disciplines, which constitute the arena for the development of pharmaceutical products. The interfaces with surrounding areas are discussed in addition to the novel organizational principles implemented in process R&D and the workflow emanating from this. Furthermore, the Tollgate model used to keep track of the progress in a project and the pre-study concept are presented in detail. Finally, the main differences between operating modes in the past and in the future are highlighted.

THE ROLE OF FISSION IN NEUTRON STAR MERGERS AND ITS IMPACT ON THE r-PROCESS PEAKS

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

Eichler, M.; Panov, I.; Rauscher, T.

2015-07-20

Comparing observational abundance features with nucleosynthesis predictions of stellar evolution or explosion simulations, we can scrutinize two aspects: (a) the conditions in the astrophysical production site and (b) the quality of the nuclear physics input utilized. We test the abundance features of r-process nucleosynthesis calculations for the dynamical ejecta of neutron star merger simulations based on three different nuclear mass models: The Finite Range Droplet Model, the (quenched version of the) Extended Thomas Fermi Model with Strutinsky Integral, and the Hartree–Fock–Bogoliubov mass model. We make use of corresponding fission barrier heights and compare the impact of four different fission fragmentmore » distribution models on the final r-process abundance distribution. In particular, we explore the abundance distribution in the second r-process peak and the rare-earth sub-peak as a function of mass models and fission fragment distributions, as well as the origin of a shift in the third r-process peak position. The latter has been noticed in a number of merger nucleosynthesis predictions. We show that the shift occurs during the r-process freeze-out when neutron captures and β-decays compete and an (n,γ)–(γ,n) equilibrium is no longer maintained. During this phase neutrons originate mainly from fission of material above A = 240. We also investigate the role of β-decay half-lives from recent theoretical advances, which lead either to a smaller amount of fissioning nuclei during freeze-out or a faster (and thus earlier) release of fission neutrons, which can (partially) prevent this shift and has an impact on the second and rare-earth peak as well.« less

Patterning of organic photovoltaic on R2R processed thin film barriers using IR laser sources

NASA Astrophysics Data System (ADS)

Fledderus, H.; Akkerman, H. B.; Salem, A.; Friedrich Schilling, N.; Klotzbach, U.

2017-02-01

We present the development of laser processes for flexible OPV on roll-to-roll (RR2R) produced thin film barrier with indium tin oxide (ITO) as transparent conductive (TC) bottom electrode. Direct laser structuring of ITO on such barrier films (so-called P1 process) is very challenging since the layers are all transparent, a complete electrical isolation is required, and the laser process should not influence the barrier performance underneath the scribes. Based on the optical properties off the SiN and ITTO, ultra-short pulse lasers inn picosecond and femtosecond regime with standard infrared (IR) wavelength as well as lasers with new a wavelength (22 μm regime) are tested for this purpose. To determine a process window for a specific laser a fixed methodology is adopted. Single pulse ablation tests were followed by scribing experiments where the pulse overlap was tuned by varying laser pulse fluence, writing speed and frequency. To verify that the laser scribing does not result inn barrier damage underneath, a new test method was developed based on the optical Ca-test. This method shows a clear improvement in damage analysis underneath laser scribes over normal optical inspection methods (e.g. microscope, optical profiler, SEM). This way clear process windows can be obtained for IR TC patterning.

Production of the entire range of r-process nuclides by black hole accretion disc outflows from neutron star mergers

NASA Astrophysics Data System (ADS)

Wu, Meng-Ru; Fernández, Rodrigo; Martínez-Pinedo, Gabriel; Metzger, Brian D.

2016-12-01

We consider r-process nucleosynthesis in outflows from black hole accretion discs formed in double neutron star and neutron star-black hole mergers. These outflows, powered by angular momentum transport processes and nuclear recombination, represent an important - and in some cases dominant - contribution to the total mass ejected by the merger. Here we calculate the nucleosynthesis yields from disc outflows using thermodynamic trajectories from hydrodynamic simulations, coupled to a nuclear reaction network. We find that outflows produce a robust abundance pattern around the second r-process peak (mass number A ˜ 130), independent of model parameters, with significant production of A < 130 nuclei. This implies that dynamical ejecta with high electron fraction may not be required to explain the observed abundances of r-process elements in metal poor stars. Disc outflows reach the third peak (A ˜ 195) in most of our simulations, although the amounts produced depend sensitively on the disc viscosity, initial mass or entropy of the torus, and nuclear physics inputs. Some of our models produce an abundance spike at A = 132 that is absent in the Solar system r-process distribution. The spike arises from convection in the disc and depends on the treatment of nuclear heating in the simulations. We conclude that disc outflows provide an important - and perhaps dominant - contribution to the r-process yields of compact binary mergers, and hence must be included when assessing the contribution of these systems to the inventory of r-process elements in the Galaxy.

Exploiting Pre-rRNA Processing in Diamond Blackfan Anemia Gene Discovery and Diagnosis

PubMed Central

Farrar, Jason E.; Quarello, Paola; Fisher, Ross; O’Brien, Kelly A.; Aspesi, Anna; Parrella, Sara; Henson, Adrianna L.; Seidel, Nancy E.; Atsidaftos, Eva; Prakash, Supraja; Bari, Shahla; Garelli, Emanuela; Arceci, Robert J.; Dianzani, Irma; Ramenghi, Ugo; Vlachos, Adrianna; Lipton, Jeffrey M.; Bodine, David M.; Ellis, Steven R.

2014-01-01

Diamond Blackfan anemia (DBA), a syndrome primarily characterized by anemia and physical abnormalities, is one among a group of related inherited bone marrow failure syndromes (IBMFS) which share overlapping clinical features. Heterozygous mutations or single-copy deletions have been identified in 12 ribosomal protein genes in approximately 60% of DBA cases, with the genetic etiology unexplained in most remaining patients. Unlike many IBMFS, for which functional screening assays complement clinical and genetic findings, suspected DBA in the absence of typical alterations of the known genes must frequently be diagnosed after exclusion of other IBMFS. We report here a novel deletion in a child that presented such a diagnostic challenge and prompted development of a novel functional assay that can assist in the diagnosis of a significant fraction of patients with DBA. The ribosomal proteins affected in DBA are required for pre-rRNA processing, a process which can be interrogated to monitor steps in the maturation of 40S and 60S ribosomal subunits. In contrast to prior methods used to assess pre-rRNA processing, the assay reported here, based on capillary electrophoresis measurement of the maturation of rRNA in pre-60S ribosomal subunits, would be readily amenable to use in diagnostic laboratories. In addition to utility as a diagnostic tool, we applied this technique to gene discovery in DBA, resulting in the identification of RPL31 as a novel DBA gene. PMID:25042156

Formation of Globular Clusters with Internal Abundance Spreads in r -Process Elements: Strong Evidence for Prolonged Star Formation

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

Bekki, Kenji; Tsujimoto, Takuji

Several globular clusters (GCs) in the Galaxy are observed to show internal abundance spreads in r -process elements (e.g., Eu). We propose a new scenario that explains the origin of these GCs (e.g., M5 and M15). In this scenario, stars with no/little abundance variations first form from a massive molecular cloud (MC). After all of the remaining gas of the MC is expelled by numerous supernovae, gas ejected from asymptotic giant branch stars can be accumulated in the central region of the GC to form a high-density intracluster medium (ICM). Merging of neutron stars then occurs to eject r -processmore » elements, which can be efficiently trapped in and subsequently mixed with the ICM. New stars formed from the ICM can have r -process abundances that are quite different from those of earlier generations of stars within the GC. This scenario can explain both (i) why r -process elements can be trapped within GCs and (ii) why GCs with internal abundance spreads in r -process elements do not show [Fe/H] spreads. Our model shows (i) that a large fraction of Eu-rich stars can be seen in Na-enhanced stellar populations of GCs, as observed in M15, and (ii) why most of the Galactic GCs do not exhibit such internal abundance spreads. Our model demonstrates that the observed internal spreads of r -process elements in GCs provide strong evidence for prolonged star formation (∼10{sup 8} yr).« less

The new model of chemical evolution of r-process elements based on the hierarchical galaxy formation. I. Ba and Eu

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

Komiya, Yutaka; Suda, Takuma; Yamada, Shimako

2014-03-10

We investigate the chemical enrichment of r-process elements in the early evolutionary stages of the Milky Way halo within the framework of hierarchical galaxy formation using a semi-analytic merger tree. In this paper, we focus on heavy r-process elements, Ba and Eu, of extremely metal-poor (EMP) stars and give constraints on their astronomical sites. Our models take into account changes of the surface abundances of EMP stars by the accretion of interstellar medium (ISM). We also consider metal-enrichment of intergalactic medium by galactic winds and the resultant pre-enrichment of proto-galaxies. The trend and scatter of the observed r-process abundances aremore » well reproduced by our hierarchical model with ∼10% of core-collapse supernovae in low-mass end (∼10 M {sub ☉}) as a dominant r-process source and the star formation efficiency of ∼10{sup –10} yr{sup –1}. For neutron star mergers as an r-process source, their coalescence timescale has to be ∼10{sup 7} yr, and the event rates ∼100 times larger than currently observed in the Galaxy. We find that the accretion of ISM is a dominant source of r-process elements for stars with [Ba/H] < –3.5. In this model, a majority of stars at [Fe/H] < –3 are formed without r-process elements, but their surfaces are polluted by the ISM accretion. The pre-enrichment affects ∼4% of proto-galaxies, and yet, is surpassed by the ISM accretion in the surface of EMP stars.« less

Approximating the r-Process on Earth with Thermonuclear Explosions. Lessons Learned and Unanswered Questions

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

Becker, Stephen Allan

2016-01-28

During the astrophysical r-process, multiple neutron captures occur so rapidly on target nuclei that their daughter nuclei generally do not have time to undergo radioactive decay before another neutron is captured. The r-process can be approximately simulated on Earth in certain types of thermonuclear explosions through an analogous process of rapid neutron captures known as the "prompt capture" process. Between 1952 and 1969, 23 nuclear tests were fielded by the US which were involved (at least partially) with the "prompt capture" process. Of these tests, 15 were at least partially successful. Some of these tests were conducted under the Plowsharemore » Peaceful Nuclear Explosion Program as scientific research experiments. It is now known that the USSR conducted similar nuclear tests during 1966 to 1979. The elements einsteinium and fermium were first discovered by this process. The most successful tests achieved 19 successive neutron captures on the initial target nuclei. A review of the US program, target nuclei used, heavy element yields, scientific achievements of the program, and how some of the results have been used by the astrophysical community is given. Finally, some unanswered questions concerning very neutron-rich nuclei that could potentially have been answered with additional nuclear experiments is presented.« less

A Systematic Translation and Cultural Adaptation Process for Three-Factor Eating Questionnaire (TFEQ-R21).

PubMed

Rosnah, I; Noor Hassim, I; Shafizah, A S

2013-10-01

The Three-Factor Eating Questionnaire was first constructed to measure eating behavior in an English population in the United States. It has been validated and translated for various populations in different languages. The aim of this article is to describe a systematic process for translating the questionnaire from English to Malay language. The report of the International Society for Pharmacoeconomics and Outcome Research (ISPOR) Task Force was used as the basis for the systematic translation process. The process began with preparation; followed by forward translation (2 independent translators), reconciliation, back translation (2 independent translators), back translation review, harmonization, cognitive debriefing, review of cognitive debriefing results and finalization, proofreading; and ended with the final report. Four independent Malay translators who fluent in English and reside in Malaysia were involved in the process. A team of health care researchers had assisted the review of the new translated questionnaires. Majority of the TFEQ-R21 items were experiencing, conceptually and semantically equivalence between original English and translated English. However, certain phrase such as "feels like bottomless pit" was difficult to translate by forward translators. Cognitive debriefing was a very helpful process to ensure the TFEQ-R21 Malay version was appropriate in term of wording and culturally accepted. A total of four redundant comments in regards to response scale wording, word confusion and wording arrangement. The systematic translation process is a way to reduce the linguistic discrepancies between the English and Malay language in order to promote equivalence and culturally adapted TFEQ-R21 questionnaire.

The pre-rRNA processing factor DEF is rate limiting for the pathogenesis of MYCN-driven neuroblastoma.

PubMed

Tao, T; Sondalle, S B; Shi, H; Zhu, S; Perez-Atayde, A R; Peng, J; Baserga, S J; Look, A T

2017-07-06

The nucleolar factor, digestive organ expansion factor (DEF), has a key role in ribosome biogenesis, functioning in pre-ribosomal RNA (pre-rRNA) processing as a component of the small ribosomal subunit (SSU) processome. Here we show that the peripheral sympathetic nervous system (PSNS) is very underdeveloped in def-deficient zebrafish, and that def haploinsufficiency significantly decreases disease penetrance and tumor growth rate in a MYCN-driven transgenic zebrafish model of neuroblastoma that arises in the PSNS. Consistent with these findings, DEF is highly expressed in human neuroblastoma, and its depletion in human neuroblastoma cell lines induces apoptosis. Interestingly, overexpression of MYCN in zebrafish and in human neuroblastoma cells results in the appearance of intermediate pre-rRNAs species that reflect the processing of pre-rRNAs through Pathway 2, a pathway that processes pre-rRNAs in a different temporal order than the more often used Pathway 1. Our results indicate that DEF and possibly other components of the SSU processome provide a novel site of vulnerability in neuroblastoma cells that could be exploited for targeted therapy.

The loop structure and the RNA helicase p72/DDX17 influence the processing efficiency of the mice miR-132

PubMed Central

Remenyi, Judit; Bajan, Sarah; Fuller-Pace, Frances V.; Arthur, J. Simon C.; Hutvagner, Gyorgy

2016-01-01

miRNAs are small RNAs that are key regulators of gene expression in eukaryotic organisms. The processing of miRNAs is regulated by structural characteristics of the RNA and is also tightly controlled by auxiliary protein factors. Among them, RNA binding proteins play crucial roles to facilitate or inhibit miRNA maturation and can be controlled in a cell, tissue and species-specific manners or in response to environmental stimuli. In this study we dissect the molecular mechanism that promotes the overexpression of miR-132 in mice over its related, co-transcribed and co-regulated miRNA, miR-212. We have shown that the loop structure of miR-132 is a key determinant for its efficient processing in cells. We have also identified a range of RNA binding proteins that recognize the loop of miR-132 and influence both miR-132 and miR-212 processing. The DEAD box helicase p72/DDX17 was identified as a factor that facilitates the specific processing of miR-132. PMID:26947125

A low initial abundance of 247Cm in the early solar system and implications for r-process nucleosynthesis

NASA Astrophysics Data System (ADS)

Stirling, Claudine H.; Halliday, Alex N.; Potter, Emma-Kate; Andersen, Morten B.; Zanda, Brigitte

2006-11-01

The short-lived nuclide 247Cm is produced by r-process nucleosynthesis. When the presolar nebula formed, 247Cm became isolated from r-process production and its abundance diminished as a result of radioactive decay. Given its short half-life of only ˜ 16 million years, 247Cm is presently extinct, but its former presence should be detectable as small variations in 235U/ 238U in primitive meteoritic material, provided Cm was chemically fractionated from U at the time these solid objects formed. The magnitude of U isotopic anomalies in meteorites can thus be used to elucidate the timing and character of the last r-process nucleosynthetic event for input into models describing the formation and evolution of the early solar system. Here we report coupled U isotopic determinations and Nd/U proxy measurements for Cm/U in a series of acid-etched leachates and mineral assemblages extracted from meteorites containing primitive phases expected to show strong Cm-U fractionations. Using multiple-collector ICPMS, we are able to determine 235U/ 238U with 2 σ analytical uncertainties of ± 1 epsilon (1 epsilon = 1 part in 10,000) on sample sizes consisting of < 3 ng of 238U and < 20 pg of 235U. A double-spiking procedure using a mixed 236U- 233U spike was employed to allow instrumental mass fractionation to be reliably corrected internally and at high precision. Uranium isotopic results for almost 40 different phases show no resolvable deviations in 235U/ 238U from the chondritic value, at the ˜ 1-2 epsilon level. These data supplement our previous observations for a suite of bulk meteorite samples [C.H. Stirling, A.N. Halliday, D. Porcelli, In search of live 247Cm in the early solar system, Geochim. Cosmochim. Acta 69 (2005) 1059-1071] and provide evidence for a solar system initial 247Cm/ 235U of < 8 × 10 - 5 . Such a low value is difficult to explain without a long time-scale of ˜ 2.3 × 10 8 years between the last actinide producing r-process event and the formation of

chipPCR: an R package to pre-process raw data of amplification curves.

PubMed

Rödiger, Stefan; Burdukiewicz, Michał; Schierack, Peter

2015-09-01

Both the quantitative real-time polymerase chain reaction (qPCR) and quantitative isothermal amplification (qIA) are standard methods for nucleic acid quantification. Numerous real-time read-out technologies have been developed. Despite the continuous interest in amplification-based techniques, there are only few tools for pre-processing of amplification data. However, a transparent tool for precise control of raw data is indispensable in several scenarios, for example, during the development of new instruments. chipPCR is an R: package for the pre-processing and quality analysis of raw data of amplification curves. The package takes advantage of R: 's S4 object model and offers an extensible environment. chipPCR contains tools for raw data exploration: normalization, baselining, imputation of missing values, a powerful wrapper for amplification curve smoothing and a function to detect the start and end of an amplification curve. The capabilities of the software are enhanced by the implementation of algorithms unavailable in R: , such as a 5-point stencil for derivative interpolation. Simulation tools, statistical tests, plots for data quality management, amplification efficiency/quantification cycle calculation, and datasets from qPCR and qIA experiments are part of the package. Core functionalities are integrated in GUIs (web-based and standalone shiny applications), thus streamlining analysis and report generation. http://cran.r-project.org/web/packages/chipPCR. Source code: https://github.com/michbur/chipPCR. stefan.roediger@b-tu.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Subsurface damage in precision ground ULE(R) and Zerodur(R) surfaces.

PubMed

Tonnellier, X; Morantz, P; Shore, P; Baldwin, A; Evans, R; Walker, D D

2007-09-17

The total process cycle time for large ULE((R)) and Zerodur((R))optics can be improved using a precise and rapid grinding process, with low levels of surface waviness and subsurface damage. In this paper, the amounts of defects beneath ULE((R)) and Zerodur((R) )surfaces ground using a selected grinding mode were compared. The grinding response was characterised by measuring: surface roughness, surface profile and subsurface damage. The observed subsurface damage can be separated into two distinct depth zones, which are: 'process' and 'machine dynamics' related.

THE UNREASONABLE WEAKNESS OF R -PROCESS COSMIC RAYS IN THE NEUTRON-STAR-MERGER NUCLEOSYNTHESIS SCENARIO

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

Kyutoku, Koutarou; Ioka, Kunihito, E-mail: koutarou.kyutoku@riken.jp

We reach the robust conclusion that, by combining the observed cosmic rays of r -process elements with the fact that the velocity of the neutron-star-merger ejecta is much higher than that of the supernova ejecta, either (1) the reverse shock in the neutron-star-merger ejecta is a very inefficient accelerator that converts less than 0.003% of the ejecta kinetic energy to the cosmic-ray energy or (2) the neutron star merger is not the origin of the Galactic r -process elements. We also find that the acceleration efficiency should be less than 0.1% for the reverse shock of the supernova ejecta withmore » observed cosmic rays lighter than the iron.« less

Analysis of launch site processing effectiveness for the Space Shuttle 26R payload

NASA Technical Reports Server (NTRS)

Flores, Carlos A.; Heuser, Robert E.; Pepper, Richard E., Jr.; Smith, Anthony M.

1991-01-01

A trend analysis study has been performed on problem reports recorded during the Space Shuttle 26R payload's processing cycle at NASA-Kennedy, using the defect-flow analysis (DFA) methodology; DFA gives attention to the characteristics of the problem-report 'population' as a whole. It is established that the problem reports contain data which distract from pressing problems, and that fully 60 percent of such reports were caused during processing at NASA-Kennedy. The second major cause of problem reports was design defects.

Enterprise Systems Value-Based R&D Portfolio Analytics: Methods, Processes, and Tools

DTIC Science & Technology

2014-01-14

Enterprise Systems Value-Based R&D Portfolio Analytics: Methods, Processes, and Tools Final Technical Report SERC -2014-TR-041-1 January 14...by the U.S. Department of Defense through the Systems Engineering Research Center ( SERC ) under Contract H98230-08-D-0171 (Task Order 0026, RT 51... SERC is a federally funded University Affiliated Research Center managed by Stevens Institute of Technology Any opinions, findings and

24 CFR 235.1220 - Processing section 235(r) mortgages under the direct endorsement program.

Code of Federal Regulations, 2010 CFR

2010-04-01

... under the direct endorsement program. 235.1220 Section 235.1220 Housing and Urban Development... National Housing Act Eligibility Requirements; Direct Endorsement § 235.1220 Processing section 235(r) mortgages under the direct endorsement program. The regulations containing the requirements which a mortgage...

Mass Measurements beyond the Major r-Process Waiting Point {sup 80}Zn

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

Baruah, S.; Herlert, A.; Schweikhard, L.

2008-12-31

High-precision mass measurements on neutron-rich zinc isotopes {sup 71m,72-81}Zn have been performed with the Penning trap mass spectrometer ISOLTRAP. For the first time, the mass of {sup 81}Zn has been experimentally determined. This makes {sup 80}Zn the first of the few major waiting points along the path of the astrophysical rapid neutron-capture process where neutron-separation energy and neutron-capture Q-value are determined experimentally. The astrophysical conditions required for this waiting point and its associated abundance signatures to occur in r-process models can now be mapped precisely. The measurements also confirm the robustness of the N=50 shell closure for Z=30.

R-HPDC Process with Forced Convection Mixing Device for Automotive Part of A380 Aluminum Alloy

PubMed Central

Zhou, Bing; Kang, Yonglin; Qi, Mingfan; Zhang, Huanhuan; Zhu, Guoming

2014-01-01

The continuing quest for cost-effective and complex shaped aluminum castings with fewer defects for applications in the automotive industries has aroused the interest in rheological high pressure die casting (R-HPDC). A new machine, forced convection mixing (FCM) device, based on the mechanical stirring and convection mixing theory for the preparation of semisolid slurry in convenience and functionality was proposed to produce the automotive shock absorber part by R-HPDC process. The effect of barrel temperature and rotational speed of the device on the grain size and morphology of semi-solid slurry were extensively studied. In addition, flow behavior and temperature field of the melt in the FCM process was investigated combining computational fluid dynamics simulation. The results indicate that the microstructure and pore defects at different locations of R-HPDC casting have been greatly improved. The vigorous fluid convection in FCM process has changed the temperature field and composition distribution of conventional solidification. Appropriately increasing the rotational speed can lead to a uniform temperature filed sooner. The lower barrel temperature leads to a larger uniform degree of supercooling of the melt that benefits the promotion of nucleation rate. Both of them contribute to the decrease of the grain size and the roundness of grain morphology. PMID:28788608

r-Process Nucleosynthesis in the Early Universe Through Fast Mergers of Compact Binaries in Triple Systems

NASA Astrophysics Data System (ADS)

Bonetti, Matteo; Perego, Albino; Capelo, Pedro R.; Dotti, Massimo; Miller, M. Coleman

2018-05-01

Surface abundance observations of halo stars hint at the occurrence of r-process nucleosynthesis at low metallicity ([Fe/H] < -3), possibly within the first 108 yr after the formation of the first stars. Possible loci of early-Universe r-process nucleosynthesis are the ejecta of either black hole-neutron star or neutron star-neutron star binary mergers. Here, we study the effect of the inclination-eccentricity oscillations raised by a tertiary (e.g. a star) on the coalescence time-scale of the inner compact object binaries. Our results are highly sensitive to the assumed initial distribution of the inner binary semi-major axes. Distributions with mostly wide compact object binaries are most affected by the third object, resulting in a strong increase (by more than a factor of 2) in the fraction of fast coalescences. If instead the distribution preferentially populates very close compact binaries, general relativistic precession prevents the third body from increasing the inner binary eccentricity to very high values. In this last case, the fraction of coalescing binaries is increased much less by tertiaries, but the fraction of binaries that would coalesce within 108 yr even without a third object is already high. Our results provide additional support to the compact-binary merger scenario for r-process nucleosynthesis.

hUTP24 is essential for processing of the human rRNA precursor at site A1, but not at site A0

PubMed Central

Tomecki, Rafal; Labno, Anna; Drazkowska, Karolina; Cysewski, Dominik; Dziembowski, Andrzej

2015-01-01

Production of ribosomes relies on more than 200 accessory factors to ensure the proper sequence of steps and faultless assembly of ribonucleoprotein machinery. Among trans-acting factors are numerous enzymes, including ribonucleases responsible for processing the large rRNA precursor synthesized by RNA polymerase I that encompasses sequences corresponding to mature 18S, 5.8S, and 25/28S rRNA. In humans, the identity of most enzymes responsible for individual processing steps, including endoribonucleases that cleave pre-rRNA at specific sites within regions flanking and separating mature rRNA, remains largely unknown. Here, we investigated the role of hUTP24 in rRNA maturation in human cells. hUTP24 is a human homolog of the Saccharomyces cerevisiae putative PIN domain-containing endoribonuclease Utp24 (yUtp24), which was suggested to participate in the U3 snoRNA-dependent processing of yeast pre-rRNA at sites A0, A1, and A2. We demonstrate that hUTP24 interacts to some extent with proteins homologous to the components of the yeast small subunit (SSU) processome. Moreover, mutation in the putative catalytic site of hUTP24 results in slowed growth of cells and reduced metabolic activity. These effects are associated with a defect in biogenesis of the 40S ribosomal subunit, which results from decreased amounts of 18S rRNA as a consequence of inaccurate pre-rRNA processing at the 5′-end of the 18S rRNA segment (site A1). Interestingly, and in contrast to yeast, site A0 located upstream of A1 is efficiently processed upon UTP24 dysfunction. Finally, hUTP24 inactivation leads to aberrant processing of 18S rRNA 2 nucleotides downstream of the normal A1 cleavage site. PMID:26237581

From Actinides to Zinc: Using the Full Abundance Pattern of the Brightest Star in Reticulum II to Distinguish between Different r-process Sites

NASA Astrophysics Data System (ADS)

Ji, Alexander P.; Frebel, Anna

2018-04-01

The ultra-faint dwarf galaxy Reticulum II was enriched by a rare and prolific r-process event, such as a neutron star merger (NSM). To investigate the nature of this event, we present high-resolution Magellan/MIKE spectroscopy of the brightest star in this galaxy. The high signal-to-noise allows us to determine the abundances of 41 elements, including the radioactive actinide element Th and first ever detections of third r-process peak elements (Os and Ir) in a star outside the Milky Way. The observed neutron-capture element abundances closely match the solar r-process component, except for the first r-process peak, which is significantly lower than solar but matches other r-process enhanced stars. The ratio of the first peak to heavier r-process elements implies that the r-process site produces roughly equal masses of high and low electron fraction ejecta, within a factor of 2. We compare the detailed abundance pattern to predictions from nucleosynthesis calculations of NSMs and magnetorotationally driven jet supernovae, finding that nuclear physics uncertainties dominate over astrophysical uncertainties. We measure {log}{{Th/Eu}}=-0.84+/- 0.06 ({stat})+/- 0.22 ({sys}), somewhat lower than all previous Th/Eu observations. The youngest age we derive from this ratio is 21.7 ± 2.8 (stat) ± 10.3 (sys) Gyr, indicating that current initial production ratios do not describe the r-process event in Reticulum II. The abundances of light elements up to Zn are consistent with extremely metal-poor Milky Way halo stars. They may eventually provide a way to distinguish between NSMs and magnetorotationally driven jet supernovae, but this would require more detailed knowledge of the chemical evolution of Reticulum II. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

Sequential processing of GNSS-R delay-Doppler maps (DDM's) for ocean wind retrieval

NASA Astrophysics Data System (ADS)

Garrison, J. L.; Rodriguez-Alvarez, N.; Hoffman, R.; Annane, B.; Leidner, M.; Kaitie, S.

2016-12-01

The delay-Doppler map (DDM) is the fundamental data product from GNSS-Reflectometry (GNSS-R), generated by cross-correlating the scattered signal with a local signal model over a range of delays and Doppler frequencies. Delay and Doppler form a set of coordinates on the ocean surface and the shape of the DDM is related to the distribution of ocean slopes. Wind speed can thus be estimated by fitting a scattering model to the shape of the observed DDM or defining an observable (e.g. average power or leading edge slope) which characterizes the change in DDM shape. For spaceborne measurements, the DDM is composed of signals scattered from a glistening zone, which can extend for up to 100 km or more. Setting a reasonable resolution requirement (25 km or less) will limit the usable portion of the DDM at each observation to only a small region near the specular point. Cyclone-GNSS (CYGNSS) is a NASA mission to study developing tropical cyclones using GNSS-R. CYGNSS science requirements call for wind retrieval with an accuracy of 10 percent above 20 m/s within a 25 km resolution. This requirement can be met using an observable defined for DDM samples between +/- 0.25 chips in delay and +/- 1 kHz in Doppler, with some filtering of the observations using a minimum threshold for range corrected gain (RCG). An improved approach, to be reviewed in this presentation, sequentially processes multiple DDM's, to combine observations generated from different "looks" at the same points on the surface. Applying this sequential process to synthetic data indicates a significant improvement in wind retrieval accuracy over a 10 km grid covering a region around the specular point. The attached figure illustrates this improvement, using simulated CYGNSS DDM's generated using the wind fields from hurricanes Earl and Danielle (left). The middle plots show wind retrievals using only an observable defined within the 25 km resolution cell. The plots on the right side show the retrievals from

Cisplatin binds to pre-miR-200b and impairs its processing to mature microRNA.

PubMed

Mezencev, R; Wartell, R M

2018-01-01

Cisplatin is an important anticancer drug with a complex mode of action, a variety of possible targets, and numerous resistance mechanisms. While genomic DNA has traditionally been considered to be its most critical anticancer target, several lines of evidence suggest that various RNAs and other biomolecules may play a role in its anticancer mode of action. In this report we demonstrate that cisplatin modifies pre-miR-200b, impairs its processing to mature miRNA, and decreases miR-200b expression in ovarian cancer cells. Considering the role of miR-200b in epithelial-to-mesenchymal transition and cancer chemosensitivity, cisplatin-induced modification of pre-miR-200b and subsequent deregulation of mature miR-200b may, depending on cell context, limit anticancer activity of this important anticancer drug. More gener- ally, precursor miRNAs may be important targets of cisplatin and play a role in this drug's anticancer activity or modulate cell responses to this drug.

Base Pairing between U3 Small Nucleolar RNA and the 5′ End of 18S rRNA Is Required for Pre-rRNA Processing

PubMed Central

Sharma, Kishor; Tollervey, David

1999-01-01

The loop of a stem structure close to the 5′ end of the 18S rRNA is complementary to the box A region of the U3 small nucleolar RNA (snoRNA). Substitution of the 18S loop nucleotides inhibited pre-rRNA cleavage at site A1, the 5′ end of the 18S rRNA, and at site A2, located 1.9 kb away in internal transcribed spacer 1. This inhibition was largely suppressed by a compensatory mutation in U3, demonstrating functional base pairing. The U3–pre-rRNA base pairing is incompatible with the structure that forms in the mature 18S rRNA and may prevent premature folding of the pre-rRNA. In the Escherichia coli pre-rRNA the homologous region of the 16S rRNA is also sequestered, in that case by base pairing to the 5′ external transcribed spacer (5′ ETS). Cleavage at site A0 in the yeast 5′ ETS strictly requires base pairing between U3 and a sequence within the 5′ ETS. In contrast, the U3-18S interaction is not required for A0 cleavage. U3 therefore carries out at least two functionally distinct base pair interactions with the pre-rRNA. The nucleotide at the site of A1 cleavage was shown to be specified by two distinct signals; one of these is the stem-loop structure within the 18S rRNA. However, in contrast to the efficiency of cleavage, the position of A1 cleavage is not dependent on the U3-loop interaction. We conclude that the 18S stem-loop structure is recognized at least twice during pre-rRNA processing. PMID:10454548

Beta-Decay Rates for Exotic Nuclei and R-Process Nucleosynthesis up to Th and U

NASA Astrophysics Data System (ADS)

Suzuki, Toshio; Yoshida, Takashi; Shibagaki, Shota; Kajino, Toshitaka; Otsuka, Takaharu

Beta-decay rates for exotic nuclei with N = 126 relevant to r-process nucleosynthesis are studied up to Z = 78 by shell-model calculations. The half-lives for the waiting-point nuclei obtained, which are short compared to a standard FRDM, are used to study r-process nucleosynthesis in neutrino-driven winds and magneto-hydrodynamic jets of core-collapse supernova explosions as well as in binary neutron star mergers. The element abundances are obtained up to the third peak as well as beyond the peak region up to thorium and uranium. Thorium and uranium are found to be produced more with the shorter shell-model half-lives and their abundances come closer to the observed values in core-collapse supernova explosions, while in case of binary neutron star mergers they are produced as much as the observed values rather independent of the half-lives.

The R and M 2000 Process and Reliability and Maintainability Management: Attitudes of Senior Level Managers in Aeronautical Systems Division

DTIC Science & Technology

1988-09-01

I .. I . . .. . - - AFIT/GLM/LSM/88S-59 THE R& M 2000 PROCESS AND RELIABILITY AND MAINTAINABILITY...respondents provided verbal responses to this question. Although one-half of these responses spoke 65 k - ’ ’ ’ i l l I l l i favorably of R& M 2000 , there were...GROUP SUB-GROUP Attitudes, Reliability, Maintainability, R& M , R&" 2000 , 05 01 I Aeronautical Systems Division, ASD 19. ABSTRACT (Continue on

β-decay Rates for Exotic Nuclei and r-process Nucleosynthesis up to Thorium and Uranium

NASA Astrophysics Data System (ADS)

Suzuki, Toshio; Shibagaki, Shota; Yoshida, Takashi; Kajino, Toshitaka; Otsuka, Takaharu

2018-06-01

Beta-decay rates for exotic nuclei with neutron magic number of N = 126 relevant to r-process nucleosynthesis are studied up to Z = 78 by shell-model calculations. The half-lives for the waiting-point nuclei obtained, which are short compared to a standard finite-range-droplet model, are used to study r-process nucleosynthesis in core-collapse supernova (CCSN) explosions and binary neutron star mergers. The element abundances are obtained up to the third peak as well as beyond the peak region up to thorium and uranium. The position of the third peak is found to be shifted toward a higher mass region in both CCSN explosions and neutron star mergers. We find that thorium and uranium elements are produced more with the shorter shell-model half-lives and their abundances come close to the observed values in CCSN explosions. In the case of binary neutron star mergers, thorium and uranium are produced consistently with the observed values independent of the half-lives.

Parameter study of r-process lanthanide production and heating rates in kilonovae

NASA Astrophysics Data System (ADS)

Lippuner, Jonas; Roberts, Luke F.

2015-04-01

Explosive r-process nucleosynthesis in material ejected during compact object mergers may lead to radioactively powered transients called kilonovae. The timescale and peak luminosity of these transients are sensitive to the composition of the material after nuclear burning ceases, as the composition determines the local heating rate from nuclear decays and the opacity. The presence of lanthanides in the ejecta can drastically increase the opacity. We use the new general-purpose nuclear reaction network SkyNet to run a parameter study of r-process nucleosynthesis for a range of initial electron fractions Ye, initial entropies s, and density decay timescales τ. We find that the ejecta is lanthanide-free for Ye >~ 0 . 22 - 0 . 3 , depending on s and τ. The heating rate is insensitive to s and τ, but certain, larger values of Ye lead to reduced heating rates, because single nuclides dominate the heating. With a simple model we estimate the luminosity, time, and effective temperature at the peak of the light curve. Since the opacity is much lower in the lanthanide-free case, we find the luminosity peaks much earlier at ~ 1 day vs. ~ 15 days in the lanthanide-rich cases. Although there is significant variation in the heating rate with Ye, changes in the heating rate do not mitigate the effect of the lanthanides. This research is partially supported by NSF under Award Numbers AST-1333520 and AST-1205732.

The origin and evolution of r- and s-process elements in the Milky Way stellar disk

NASA Astrophysics Data System (ADS)

Battistini, Chiara; Bensby, Thomas

2016-02-01

Context. Elements heavier than iron are produced through neutron-capture processes in the different phases of stellar evolution. Asymptotic giant branch (AGB) stars are believed to be mainly responsible for elements that form through the slow neutron-capture process, while the elements created in the rapid neutron-capture process have production sites that are less understood. Knowledge of abundance ratios as functions of metallicity can lead to insight into the origin and evolution of our Galaxy and its stellar populations. Aims: We aim to trace the chemical evolution of the neutron-capture elements Sr, Zr, La, Ce, Nd, Sm, and Eu in the Milky Way stellar disk. This will allow us to constrain the formation sites of these elements, as well as to probe the evolution of the Galactic thin and thick disks. Methods: Using spectra of high resolution (42 000 ≲ R ≲ 65 000) and high signal-to-noise (S/N ≳ 200) obtained with the MIKE and the FEROS spectrographs, we determine Sr, Zr, La, Ce, Nd, Sm, and Eu abundances for a sample of 593 F and G dwarf stars in the solar neighborhood. The abundance analysis is based on spectral synthesis using one-dimensional, plane-parallel, local thermodynamic equilibrium (LTE) model stellar atmospheres calculated with the MARCS 2012 code. Results: We present abundance results for Sr (156 stars), Zr (311 stars), La (242 stars), Ce (365 stars), Nd (395 stars), Sm (280 stars), and Eu (378 stars). We find that Nd, Sm, and Eu show trends similar to what is observed for the α elements in the [X/Fe]-[Fe/H] abundance plane. For [Sr/Fe] and [Zr/Fe], we find decreasing abundance ratios for increasing metallicity, reaching sub-solar values at super-solar metallicities. [La/Fe] and [Ce/Fe] do not show any clear trend with metallicity, and they are close to solar values at all [Fe/H]. The trends of abundance ratios [X/Fe] as a function of stellar ages present different slopes before and after 8 Gyr. Conclusions: The rapid neutron-capture process is

R-Ras2 is required for germinal center formation to aid B cells during energetically demanding processes.

PubMed

Mendoza, Pilar; Martínez-Martín, Nuria; Bovolenta, Elena R; Reyes-Garau, Diana; Hernansanz-Agustín, Pablo; Delgado, Pilar; Diaz-Muñoz, Manuel D; Oeste, Clara L; Fernández-Pisonero, Isabel; Castellano, Ester; Martínez-Ruiz, Antonio; Alonso-Lopez, Diego; Santos, Eugenio; Bustelo, Xosé R; Kurosaki, Tomohiro; Alarcón, Balbino

2018-05-29

Upon antigen recognition within peripheral lymphoid organs, B cells interact with T cells and other immune cells to transiently form morphological structures called germinal centers (GCs), which are required for B cell clonal expansion, immunoglobulin class switching, and affinity maturation. This process, known as the GC response, is an energetically demanding process that requires the metabolic reprogramming of B cells. We showed that the Ras-related guanosine triphosphate hydrolase (GTPase) R-Ras2 (also known as TC21) plays an essential, nonredundant, and B cell-intrinsic role in the GC response. Both the conversion of B cells into GC B cells and their expansion were impaired in mice lacking R-Ras2, but not in those lacking a highly related R-Ras subfamily member or both the classic H-Ras and N-Ras GTPases. In the absence of R-Ras2, activated B cells did not exhibit increased oxidative phosphorylation or aerobic glycolysis. We showed that R-Ras2 was an effector of both the B cell receptor (BCR) and CD40 and that, in its absence, B cells exhibited impaired activation of the PI3K-Akt-mTORC1 pathway, reduced mitochondrial DNA replication, and decreased expression of genes involved in glucose metabolism. Because most human B cell lymphomas originate from GC B cells or B cells that have undergone the GC response, our data suggest that R-Ras2 may also regulate metabolism in B cell malignancies. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Field testing results for the R-BTEX{sup {trademark}} process for controlling glycol dehydrator emissions

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

Gamez, J.P.; Rueter, C.O.; Beitler, C.M.

1995-12-01

lncreasing regulatory pressure has made emissions of benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX) and total volatile organic compounds (VOC) from glycol dehydration units a major concern for the natural gas industry since there are over 40,000 of these units in operation. The Clean Air Act Amendments (CAAA) of 1990 have been the impetus for air toxics regulations, and the Maximum Achievable Control Technology (MACT) standards for the oil and gas industry will be proposed in June, 1995, and will include glycol dehydrators. In addition, several states are regulating or considering regulation of these units. The most commonmore » control systems that have been applied to glycol dehydrators are combustion or condensation systems. Combustion systems suffer from high operating costs since they do not recover the hydrocarbon for sale and require supplemental fuel. Many of the condensation systems may not achieve sufficiently low condenser temperatures to meet regulatory control limits. The R-BTEX{sup TM} process addresses this shortcoming by recovering the steam from the glycol dehydrator and converting it to cooling water; this allows R-BTEX to achieve the lowest condenser temperature possible without refrigeration. The Gas Research Institute (GRI) is conducting a field test program to demonstrate the process under a variety of conditions. Under this program, testing has been completed at one site in south Texas and at another site in western Colorado. Startup of a third unit at a Gulf Coast site in Texas should occur in late 1994. This paper presents the testing results for the first two sites and includes a side-by-side comparison of the R-BTEX process with other available control technologies.« less

Nop9 is a PUF-like protein that prevents premature cleavage to correctly process pre-18S rRNA

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

Zhang, Jun; McCann, Kathleen L.; Qiu, Chen

Numerous factors direct eukaryotic ribosome biogenesis, and defects in a single ribosome assembly factor may be lethal or produce tissue-specific human ribosomopathies. Pre-ribosomal RNAs (pre-rRNAs) must be processed stepwise and at the correct subcellular locations to produce the mature rRNAs. Nop9 is a conserved small ribosomal subunit biogenesis factor, essential in yeast. Here we report a 2.1-Å crystal structure of Nop9 and a small-angle X-ray-scattering model of a Nop9:RNA complex that reveals a ‘C’-shaped fold formed from 11 Pumilio repeats. We show that Nop9 recognizes sequence and structural features of the 20S pre-rRNA near the cleavage site of the nuclease,more » Nob1. We further demonstrate that Nop9 inhibits Nob1 cleavage, the final processing step to produce mature small ribosomal subunit 18S rRNA. Together, our results suggest that Nop9 is critical for timely cleavage of the 20S pre-rRNA. Moreover, the Nop9 structure exemplifies a new class of Pumilio repeat proteins.« less

Probing the Site for r-Process Nucleosynthesis with Abundances of Barium and Magnesium in Extremely Metal-poor Stars.

PubMed

Tsujimoto; Shigeyama; Yoshii

2000-03-01

We suggest that if the astrophysical site for r-process nucleosynthesis in the early Galaxy is confined to a narrow mass range of Type II supernova (SN II) progenitors, with a lower mass limit of Mms=20 M middle dot in circle, a unique feature in the observed distribution of [Ba/Mg] versus [Mg/H] for extremely metal-poor stars can be adequately reproduced. We associate this feature, a bifurcation of the observed elemental ratios into two branches in the Mg abundance interval -3.7processes. The first branch, which we call the y-branch, is associated with the production of Ba and Mg from individual massive supernovae. The derived mass of Ba synthesized in SNe II is 8.5x10-6 M middle dot in circle for Mms=20 M middle dot in circle and 4.5x10-8 M middle dot in circle for Mms=25 M middle dot in circle. We conclude that SNe II with Mms approximately 20 M middle dot in circle are the dominant source of r-process nucleosynthesis in the early Galaxy. An SN-induced chemical evolution model with this Mms-dependent Ba yield creates the y-branch, reflecting the different nucleosynthesis yields of [Ba/Mg] for each SN II with Mms greater, similar20 M middle dot in circle. The second branch, which we call the i-branch, is associated with the elemental abundance ratios of stars which were formed in the dense shells of the interstellar medium swept up by SNe II with Mms<20 M middle dot in circle that do not synthesize r-process elements, and it applies to stars with observed Mg abundances in the range &sqbl0;Mg&solm0;H&sqbr0;<-2.7. The Ba abundances in these stars reflect those of the interstellar gas at the (later) time of their formation. The existence of a [Ba/Mg] i-branch strongly suggests that SNe II that are associated with stars of progenitor mass Mmsr-process elements. We predict the existence of this i-branch for other r-process elements, such as

Active-sterile neutrino conversion: consequences for the r-process and supernova neutrino detection

NASA Astrophysics Data System (ADS)

Fetter, J.; McLaughlin, G. C.; Balantekin, A. B.; Fuller, G. M.

2003-02-01

We examine active-sterile neutrino conversion in the late time post-core-bounce supernova environment. By including the effect of feedback on the Mikheyev-Smirnov-Wolfenstein (MSW) conversion potential, we obtain a large range of neutrino mixing parameters which produce a favorable environment for the r-process. We look at the signature of this effect in the current generation of neutrino detectors now coming on line. We also investigate the impact of the neutrino-neutrino forward-scattering-induced potential on the MSW conversion.

A divergent Pumilio repeat protein family for pre-rRNA processing and mRNA localization

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

Qiu, Chen; McCann, Kathleen L.; Wine, Robert N.

Pumilio/feminization of XX and XO animals (fem)-3 mRNA-binding factor (PUF) proteins bind sequence specifically to mRNA targets using a single-stranded RNA-binding domain comprising eight Pumilio (PUM) repeats. PUM repeats have now been identified in proteins that function in pre-rRNA processing, including human Puf-A and yeast Puf6. This is a role not previously ascribed to PUF proteins. In this paper we present crystal structures of human Puf-A that reveal a class of nucleic acid-binding proteins with 11 PUM repeats arranged in an “L”-like shape. In contrast to classical PUF proteins, Puf-A forms sequence-independent interactions with DNA or RNA, mediated by conservedmore » basic residues. We demonstrate that equivalent basic residues in yeast Puf6 are important for RNA binding, pre-rRNA processing, and mRNA localization. Finally, PUM repeats can be assembled into alternative folds that bind to structured nucleic acids in addition to forming canonical eight-repeat crescent-shaped RNA-binding domains found in classical PUF proteins.« less

A divergent Pumilio repeat protein family for pre-rRNA processing and mRNA localization

DOE PAGES

Qiu, Chen; McCann, Kathleen L.; Wine, Robert N.; ...

2014-12-15

Pumilio/feminization of XX and XO animals (fem)-3 mRNA-binding factor (PUF) proteins bind sequence specifically to mRNA targets using a single-stranded RNA-binding domain comprising eight Pumilio (PUM) repeats. PUM repeats have now been identified in proteins that function in pre-rRNA processing, including human Puf-A and yeast Puf6. This is a role not previously ascribed to PUF proteins. In this paper we present crystal structures of human Puf-A that reveal a class of nucleic acid-binding proteins with 11 PUM repeats arranged in an “L”-like shape. In contrast to classical PUF proteins, Puf-A forms sequence-independent interactions with DNA or RNA, mediated by conservedmore » basic residues. We demonstrate that equivalent basic residues in yeast Puf6 are important for RNA binding, pre-rRNA processing, and mRNA localization. Finally, PUM repeats can be assembled into alternative folds that bind to structured nucleic acids in addition to forming canonical eight-repeat crescent-shaped RNA-binding domains found in classical PUF proteins.« less

Helping science to succeed: improving processes in R&D.

PubMed

Sewing, Andreas; Winchester, Toby; Carnell, Pauline; Hampton, David; Keighley, Wilma

2008-03-01

Bringing drugs to the market remains a costly and, until now, often unpredictable challenge. Although understanding the underlying science is key to further progress, our imperfect knowledge of disease and complex biological systems leaves excellence in execution as the most tangible lever to sustain our serendipitous approach to drug discovery. The problems encountered in pharmaceutical R&D are not unique, but to learn from other industries it is important to recognise similarity, rather than differences, and to advance industrialisation of R&D beyond technology and automation. Tools like Lean and Six Sigma, already applied to increase business excellence across diverse organisations, can equally be introduced to pharmaceutical R&D and offer the potential to transform operations without large-scale investment.

Nanohole and dot patterning processes on quartz substrate by R-θ electron beam lithography and nanoimprinting

NASA Astrophysics Data System (ADS)

Watanabe, Tsuyoshi; Taniguchi, Kazutake; Suzuki, Kouta; Iyama, Hiromasa; Kishimoto, Shuji; Sato, Takashi; Kobayashi, Hideo

2016-06-01

Fine hole and dot patterns with bit pitches (bp’s) of less than 40 nm were fabricated in the circular band area of a quartz substrate by R-θ electron beam lithography (EBL), reactive ion etching (RIE), and nanoimprinting. These patterning processes were studied to obtain minimum pitch sizes of hole and dot patterns without pattern collapse. The patterning on the circular band was aimed to apply these patterning processes to future high-density bit-patterned media (BPM) for hard disk drive (HDD) and permanent memory for the long life archiving of digital data. In hole patterning, a minimum-22-nm-bp and 8.2-nm-diameter pattern (1.3 Tbit/in.2) was obtained on a quartz substrate by optimizing the R-θ EBL and RIE processes. Dot patterns were replicated on another quartz substrate by nanoimprinting using a hole-patterned quartz substrate as a master mold followed by RIE. In dot patterning, a minimum-30-nm-bp and 18.5-nm-diameter pattern (0.7 Tbit/in.2) was obtained by introducing new descum conditions. It was observed that the minimum bp of successful patterning increased as the fabrication process proceeded, i.e., from 20 nm bp in the first EBL process to 30 nm bp in the last quartz dot patterning process. From the measured diameters of the patterns, it was revealed that pattern collapse was apt to occur when the value of average diameter plus 3 sigma of diameter was close to the bp. It was suggested that multiple fabrication processes caused the degradation of pattern quality; therefore, hole patterning is more suitable than dot patterning for future applications owing to the lower quality degradation by its simple fabrication process.

Oligomers, protofibrils and amyloid fibrils from recombinant human lysozyme (rHL): fibrillation process and cytotoxicity evaluation for ARPE-19 cell line.

PubMed

Ruiz, Eva D; Almada, Mario; Burboa, María G; Taboada, Pablo; Mosquera, Víctor; Valdez, Miguel A; Juárez, Josué

2015-02-01

Amyloid-associated diseases, such Alzheimer's, Huntington's, Parkinson's, and type II diabetes, are related to protein misfolding and aggregation. Herein, the time evolution of scattered light intensity, hydrophobic properties, and conformational changes during fibrillation processes of rHL solutions at 55 °C and pH 2.0 were used to monitor the aggregation process of recombinant human lysozyme (rHL). Dynamic light scattering (DLS), thioflavin T (ThT) fluorescence, and surface tension (ST) at the air-water interface were used to analyze the hydrophobic properties of pre-amyloid aggregates involved in the fibrillation process of rHL to find a correlation between the hydrophobic character of oligomers, protofibrils and amyloid aggregates with the gain in cross-β-sheet structure, depending on the increase in the incubation periods. The ability of the different aggregates of rHL isolated during the fibrillation process to be adsorbed at the air-water interface can provide important information about the hydrophobic properties of the protein, which can be related to changes in the secondary structure of rHL, resulting in cytotoxic or non-cytotoxic species. Thus, we evaluated the cytotoxic effect of oligomers, protofibrils and amyloid fibrils on the cell line ARPE-19 using the MTT reduction test. The more cytotoxic protein species arose after a 600-min incubation time, suggesting that the hydrophobic character of pre-amyloid fibrils, in addition to the high prevalence of the cross-β-sheet conformation, can become toxic for the cell line ARPE-19. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparative study of the bioconversion process using R-(+)- and S-(-)-limonene as substrates for Fusarium oxysporum 152B.

PubMed

Molina, Gustavo; Bution, Murillo L; Bicas, Juliano L; Dolder, Mary Anne Heidi; Pastore, Gláucia M

2015-05-01

This study compared the bioconversion process of S-(-)-limonene into limonene-1,2-diol with the already established biotransformation of R-(+)-limonene into α-terpineol using the same biocatalyst in both processes, Fusarium oxysporum 152B. The bioconversion of the S-(-)-isomer was tested on cell permeabilisation under anaerobic conditions and using a biphasic system. When submitted to permeabilisation trials, this biocatalyst has shown a relatively high resistance; still, no production of limonene-1,2-diol and a loss of activity of the biocatalyst were observed after intense cell treatment, indicating a complete loss of cell viability. Furthermore, the results showed that this process can be characterised as an aerobic system that was catalysed by limonene-1,2-epoxide hydrolase, had an intracellular nature and was cofactor-dependent because the final product was not detected by an anaerobic process. Finally, this is the first report to characterise the bioconversion of R-(+)- and S-(-)-limonene by cellular detoxification using ultra-structural analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

R/V Kilo Moana's New Geophysical Instrumentation, Processing Methods, and Online Data Repository

NASA Astrophysics Data System (ADS)

Miller, J. E.; Chandler, M. T.; Taylor, B.; Shor, A.; Ferguson, J. S.; Wessel, P.

2012-12-01

In 2012 several upgrades were made to the underway geophysical systems on R/V Kilo Moana, which the University of Hawaii School of Ocean and Earth Science and Technology (SOEST) operates as part of the University-National Oceanographic Laboratory System (UNOLS) fleet. New instrumentation includes a Bell BGM-3 forced feedback-type gravimeter, a Kongsberg EM 122 12-kHz receiver array, and a high resolution 70-100 kHz EM 710 multibeam echo sounder. Multibeam acceptance trials carried out in June by the Multibeam Advisory Committee, Gates Acoustic Services and UH-SOEST found that both sonars are performing within expected levels with ~5x water depth (WD) for the EM 710 system in shallow water and ~19 km swath width at 4,700 m depth (~4x WD) for the EM 122 deep water system. UH-SOEST also took steps this year to fulfill its obligation to make Kilo Moana's geophysical data more accessible to the public. After an audit of Kilo Moana data at SOEST, Lamont's Rolling Deck to Repository (R2R) and the National Geophysical Data Center (NGDC), as of July 2012 all National Science Foundation-funded Kilo Moana multibeam, gravity, magnetics, center beam depth and Acoustic Doppler Current Profiler (ADCP) data have been submitted to R2R and any multibeam data over 2 years old is being transferred to NGDC. Because it had previously been difficult to access some of SOEST's geophysical data, updated data processing routines have been developed for converting raw gravity, magnetics, and centerbeam depth data to NGDC's standard marine data exchange format (MGD77) for archival and dissemination by NGDC. MGD77 files are being generated and inspected using rigorous along-track analytical techniques for ~270 surveys dating from 2002 to the present and are being submitted to NGDC. We are also developing an online data portal to further facilitate access to SOEST data.

Explaining the Ba, Y, Sr, and Eu abundance scatter in metal-poor halo stars: constraints to the r-process

NASA Astrophysics Data System (ADS)

Cescutti, G.; Chiappini, C.

2014-05-01

Context. Thanks to the heroic observational campaigns carried out in recent years we now have large samples of metal-poor stars for which measurements of detailed abundances exist. In particular, large samples of stars with metallicities -5 < [Fe/H] <-1 and measured abundances of Sr, Ba, Y, and Eu are now available. These data hold important clues on the nature of the contribution of the first stellar generations to the enrichment of our Galaxy. Aims: We aim to explain the scatter in Sr, Ba, Y, and Eu abundance ratio diagrams unveiled by the metal-poor halo stars. Methods: We computed inhomogeneous chemical evolution models for the Galactic halo assuming different scenarios for the r-process site: the electron-capture (EC) supernovae and the magnetorotationally driven (MRD) supernovae scenarios. We also considered models with and without the contribution of fast-rotating massive stars (spinstars) to an early enrichment by the s-process. A detailed comparison with the now large sample of stars with measured abundances of Sr, Ba, Y, Eu, and Fe is provided (both in terms of scatter plots and number distributions for several abundance ratios). Results: The scatter observed in these abundance ratios of the very metal-poor stars (with [Fe/H] <-2.5) can be explained by combining the s-process production in spinstars, and the r-process contribution coming from massive stars. For the r-process we have developed models for both the EC and the MRD scenarios that match the observations. Conclusions: With the present observational and theoretical constraints we cannot distinguish between the EC and the MRD scenarios in the Galactic halo. Independently of the r-process scenarios adopted, the production of elements by an s-process in spinstars is needed to reproduce the spread in abundances of the light neutron capture elements (Sr and Y) over heavy neutron capture elements (Ba and Eu). We provide a way to test our suggestions by means of the distribution of the Ba isotopic

Process R&D under the magnifying glass: organization, business model, challenges, and scientific context.

PubMed

Federsel, Hans-Jürgen

2010-08-15

Initially, the aim is to provide the big picture illustrating the as is situation in the pharmaceutical industry: a lack of productivity resulting in too few products reaching the market; a loss of billions in revenue over the next few years as some of the major megabrands go off patent; a spiraling cost for developing new drugs and taking them through clinical and safety studies. Following on, a look deeper into the organization will offer an insight into the state-of-the-art in a technical function accountable for chemical Process R&D (with a remit to develop scalable, robust, and cost efficient processes for small molecules). The vast majority of compounds already launched in the form of drug products on the market or still being pursued through the phases of discovery and development, fall within the category of small molecules (as opposed to biopharmaceuticals, e.g., proteins, monoclonal antibodies). This typically means molecular weights of <1000Da and puts organic synthesis in the widest sense of the word at the forefront of technologies needed to support R&D programs in the pharma industry. Understandably, the demands on Medicinal Chemistry are quite different to what applies in a Process R&D (PR&D) organization. In the former, making large numbers of potentially interesting molecules, many of which are discarded after testing, is a key driver and for this virtually any synthetic methodology will suffice. For PR&D, however, homing in on selected compounds there is an expectation that the best synthetic routes will be delivered that meet a number of tough criteria, for instance from an environmental and safety point of view, allowing operation on large scale, offering cost competitiveness, avoiding patent infringements, showing sustainability for long-term production, etc. The intention is to focus on issues to be addressed during this transition by providing examples of changes that had to be put in place in order to make the supply of larger amounts of

New Fission Fragment Distributions and r-Process Origin of the Rare-Earth Elements

NASA Astrophysics Data System (ADS)

Goriely, S.; Sida, J.-L.; Lemaître, J.-F.; Panebianco, S.; Dubray, N.; Hilaire, S.; Bauswein, A.; Janka, H.-T.

2013-12-01

Neutron star (NS) merger ejecta offer a viable site for the production of heavy r-process elements with nuclear mass numbers A≳140. The crucial role of fission recycling is responsible for the robustness of this site against many astrophysical uncertainties, but calculations sensitively depend on nuclear physics. In particular, the fission fragment yields determine the creation of 110≲A≲170 nuclei. Here, we apply a new scission-point model, called SPY, to derive the fission fragment distribution (FFD) of all relevant neutron-rich, fissioning nuclei. The model predicts a doubly asymmetric FFD in the abundant A≃278 mass region that is responsible for the final recycling of the fissioning material. Using ejecta conditions based on relativistic NS merger calculations, we show that this specific FFD leads to a production of the A≃165 rare-earth peak that is nicely compatible with the abundance patterns in the Sun and metal-poor stars. This new finding further strengthens the case of NS mergers as possible dominant origin of r nuclei with A≳140.

Low-frequency repetitive transcranial magnetic stimulation (rTMS) affects event-related potential measures of novelty processing in autism.

PubMed

Sokhadze, Estate; Baruth, Joshua; Tasman, Allan; Mansoor, Mehreen; Ramaswamy, Rajesh; Sears, Lonnie; Mathai, Grace; El-Baz, Ayman; Casanova, Manuel F

2010-06-01

In our previous study on individuals with autism spectrum disorder (ASD) (Sokhadze et al., Appl Psychophysiol Biofeedback 34:37-51, 2009a) we reported abnormalities in the attention-orienting frontal event-related potentials (ERP) and the sustained-attention centro-parietal ERPs in a visual oddball experiment. These results suggest that individuals with autism over-process information needed for the successful differentiation of target and novel stimuli. In the present study we examine the effects of low-frequency, repetitive Transcranial Magnetic Stimulation (rTMS) on novelty processing as well as behavior and social functioning in 13 individuals with ASD. Our hypothesis was that low-frequency rTMS application to dorsolateral prefrontal cortex (DLFPC) would result in an alteration of the cortical excitatory/inhibitory balance through the activation of inhibitory GABAergic double bouquet interneurons. We expected to find post-TMS differences in amplitude and latency of early and late ERP components. The results of our current study validate the use of low-frequency rTMS as a modulatory tool that altered the disrupted ratio of cortical excitation to inhibition in autism. After rTMS the parieto-occipital P50 amplitude decreased to novel distracters but not to targets; also the amplitude and latency to targets increased for the frontal P50 while decreasing to non-target stimuli. Low-frequency rTMS minimized early cortical responses to irrelevant stimuli and increased responses to relevant stimuli. Improved selectivity in early cortical responses lead to better stimulus differentiation at later-stage responses as was made evident by our P3b and P3a component findings. These results indicate a significant change in early, middle-latency and late ERP components at the frontal, centro-parietal, and parieto-occipital regions of interest in response to target and distracter stimuli as a result of rTMS treatment. Overall, our preliminary results show that rTMS may prove to

Enabling Web-Based Analysis of CUAHSI HIS Hydrologic Data Using R and Web Processing Services

NASA Astrophysics Data System (ADS)

Ames, D. P.; Kadlec, J.; Bayles, M.; Seul, M.; Hooper, R. P.; Cummings, B.

2015-12-01

The CUAHSI Hydrologic Information System (CUAHSI HIS) provides open access to a large number of hydrological time series observation and modeled data from many parts of the world. Several software tools have been designed to simplify searching and access to the CUAHSI HIS datasets. These software tools include: Desktop client software (HydroDesktop, HydroExcel), developer libraries (WaterML R Package, OWSLib, ulmo), and the new interactive search website, http://data.cuahsi.org. An issue with using the time series data from CUAHSI HIS for further analysis by hydrologists (for example for verification of hydrological and snowpack models) is the large heterogeneity of the time series data. The time series may be regular or irregular, contain missing data, have different time support, and be recorded in different units. R is a widely used computational environment for statistical analysis of time series and spatio-temporal data that can be used to assess fitness and perform scientific analyses on observation data. R includes the ability to record a data analysis in the form of a reusable script. The R script together with the input time series dataset can be shared with other users, making the analysis more reproducible. The major goal of this study is to examine the use of R as a Web Processing Service for transforming time series data from the CUAHSI HIS and sharing the results on the Internet within HydroShare. HydroShare is an online data repository and social network for sharing large hydrological data sets such as time series, raster datasets, and multi-dimensional data. It can be used as a permanent cloud storage space for saving the time series analysis results. We examine the issues associated with running R scripts online: including code validation, saving of outputs, reporting progress, and provenance management. An explicit goal is that the script which is run locally should produce exactly the same results as the script run on the Internet. Our design can

Half-lives and branchings for {beta}-delayed neutron emission for neutron-rich Co-Cu isotopes in the r-process

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

Hosmer, P.; Estrade, A.; Montes, F.

The {beta} decays of very neutron-rich nuclides in the Co-Zn region were studied experimentally at the National Superconducting Cyclotron Laboratory using the NSCL {beta}-counting station in conjunction with the neutron detector NERO. We measured the branchings for {beta}-delayed neutron emission (P{sub n} values) for {sup 74}Co (18{+-}15%) and {sup 75-77}Ni (10{+-}2.8%, 14{+-}3.6%, and 30{+-}24%, respectively) for the first time, and remeasured the P{sub n} values of {sup 77-79}Cu, {sup 79,81}Zn, and {sup 82}Ga. For {sup 77-79}Cu and for {sup 81}Zn we obtain significantly larger P{sub n} values compared to previous work. While the new half-lives for the Ni isotopes frommore » this experiment had been reported before, we present here in addition the first half-life measurements of {sup 75}Co (30{+-}11 ms) and {sup 80}Cu (170{sub -50}{sup +110} ms). Our results are compared with theoretical predictions, and their impact on various types of models for the astrophysical rapid neutron-capture process (r-process) is explored. We find that with our new data, the classical r-process model is better able to reproduce the A=78-80 abundance pattern inferred from the solar abundances. The new data also influence r-process models based on the neutrino-driven high-entropy winds in core collapse supernovae.« less

Physics and Process Modeling (PPM) and Other Propulsion R and T. Volume 1; Materials Processing, Characterization, and Modeling; Lifting Models

NASA Technical Reports Server (NTRS)

1997-01-01

This CP contains the extended abstracts and presentation figures of 36 papers presented at the PPM and Other Propulsion R&T Conference. The focus of the research described in these presentations is on materials and structures technologies that are parts of the various projects within the NASA Aeronautics Propulsion Systems Research and Technology Base Program. These projects include Physics and Process Modeling; Smart, Green Engine; Fast, Quiet Engine; High Temperature Engine Materials Program; and Hybrid Hyperspeed Propulsion. Also presented were research results from the Rotorcraft Systems Program and work supported by the NASA Lewis Director's Discretionary Fund. Authors from NASA Lewis Research Center, industry, and universities conducted research in the following areas: material processing, material characterization, modeling, life, applied life models, design techniques, vibration control, mechanical components, and tribology. Key issues, research accomplishments, and future directions are summarized in this publication.

MicroRNAs modulating angiogenesis: miR-129-1 and miR-133 act as angio-miR in HUVECs.

PubMed

Soufi-Zomorrod, Mina; Hajifathali, Abbas; Kouhkan, Fatemeh; Mehdizadeh, Mahshid; Rad, Seyed Mohammad Ali Hosseini; Soleimani, Masoud

2016-07-01

The sprouting of new blood vessels by angiogenesis is critical in vascular development and homeostasis. Aberrant angiogenesis leads to enormous pathological conditions such as ischemia and cancer. MicroRNAs (also known as miRNAs or miRs) play key roles in regulation of a range of cellular processes by posttranscriptional suppression of their target genes. Recently, new studies have indicated that miRNAs are involved in certain angiogenic settings and signaling pathways use these non-coding RNAs to promote or suppress angiogenic processes. Herein, VEGFR2 and FGFR1 were identified as miR-129-1 and miR-133 targets using bioinformatic algorithms, respectively. Afterwards, using luciferase reporter assay and gene expression analysis at both mRNA and protein levels, VEGFR2 and FGFR1 were validated as miR-129-1 and miR-133 targets. In addition, we showed that miR-129-1 and miR-133 suppress angiogenesis properties such as proliferation rate, cell viability, and migration activity of human umbilical vein endothelial cells (HUVEC) in vitro. We conclude that these miRNAs can suppress key factors of angiogenesis by directly targeting them. These results have important therapeutic implications for a variety of diseases involving deregulation of angiogenesis, including cancer.

High-resolution microscopy of active ribosomal genes and key members of the rRNA processing machinery inside nucleolus-like bodies of fully-grown mouse oocytes.

PubMed

Shishova, Kseniya V; Khodarovich, Yuriy M; Lavrentyeva, Elena A; Zatsepina, Olga V

2015-10-01

Nucleolus-like bodies (NLBs) of fully-grown (germinal vesicle, GV) mammalian oocytes are traditionally considered as morphologically distinct entities, which, unlike normal nucleoli, contain transcribed ribosomal genes (rDNA) solely at their surface. In the current study, we for the first time showed that active ribosomal genes are present not only on the surface but also inside NLBs of the NSN-type oocytes. The "internal" rRNA synthesis was evidenced by cytoplasmic microinjections of BrUTP as precursor and by fluorescence in situ hybridization with a probe to the short-lived 5'ETS segment of the 47S pre-rRNA. We further showed that in the NLB mass of NSN-oocytes, distribution of active rDNA, RNA polymerase I (UBF) and rRNA processing (fibrillarin) protein factors, U3 snoRNA, pre-rRNAs and 18S/28S rRNAs is remarkably similar to that in somatic nucleoli capable to make pre-ribosomes. Overall, these observations support the occurrence of rDNA transcription, rRNA processing and pre-ribosome assembly in the NSN-type NLBs and so that their functional similarity to normal nucleoli. Unlike the NSN-type NLBs, the NLBs of more mature SN-oocytes do not contain transcribed rRNA genes, U3 snoRNA, pre-rRNAs, 18S and 28S rRNAs. These results favor the idea that in a process of transformation of NSN-oocytes to SN-oocytes, NLBs cease to produce pre-ribosomes and, moreover, lose their rRNAs. We also concluded that a denaturing fixative 70% ethanol used in the study to fix oocytes could be more appropriate for light microscopy analysis of nucleolar RNAs and proteins in mammalian fully-grown oocytes than a commonly used cross-linking aldehyde fixative, formalin. Copyright © 2015 Elsevier Inc. All rights reserved.

Inactivation of p53 in pterygium influence miR-200a expression resulting in ZEB1/ZEB2 up-regulation and EMT processing.

PubMed

Wu, Chueh-Wei; Peng, Mei-Ling; Yeh, Ken-Tu; Tsai, Yi-Yu; Chiang, Chun-Chi; Cheng, Ya-Wen

2016-05-01

Loss of p53 function has been linked to progression of pterygium. MiR-200a is known to be controlled by p53. Here, we hypothesize that expression of miR-200a and downstream ZEB1/ZEB2 genes are regulated epithelial-mesenchymal transition (EMT) involved in the pathogenesis and recurrence of pterygium. For this study, 120 primary pterygial samples were collected. Immunohistochemistry and real-time RT-PCR were performed to determine the expression of p53, p53 down-stream EMT associated protein and miR-200a. The molecular correlation of p53, miR-200a and downstream genes were confirmed using primary pterygium cells (PECs). Expression of miR-200a in pterygium tissues was significantly lower than in conjunctiva controls (p = 0.015). Up-regulated miR-200a levels were positively correlated with and p53 protein expression (p < 0.001). The miR-200a downstream ZEB1/ZEB1 protein expression were negative correlated with miR-200a expression. Cell model studies demonstrated that miR-200a controlled the EMT of PECs through up-regulated ZEB1, ZEB2 and Snail gene expression. Our study demonstrated that inactivation of p53 in pterygium may influence miR-200a, resulting in ZEB1/ZEB2 up-regulation and EMT processing of pterygium. Therefore, we suggest that expression of miR-200a play an important role in EMT processing and recurrence of pterygium. Copyright © 2016 Elsevier Ltd. All rights reserved.

Export Control Requirements for Tritium Processing Design and R&D

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

Hollis, William Kirk; Maynard, Sarah-Jane Wadsworth

This document will address requirements of export control associated with tritium plant design and processes. Los Alamos National Laboratory has been working in the area of tritium plant system design and research and development (R&D) since the early 1970’s at the Tritium Systems Test Assembly (TSTA). This work has continued to the current date with projects associated with the ITER project and other Office of Science Fusion Energy Science (OS-FES) funded programs. ITER is currently the highest funding area for the DOE OS-FES. Although export control issues have been integrated into these projects in the past a general guidance documentmore » has not been available for reference in this area. To address concerns with currently funded tritium plant programs and assist future projects for FES, this document will identify the key reference documents and specific sections within related to tritium research. Guidance as to the application of these sections will be discussed with specific detail to publications and work with foreign nationals.« less

Export Control Requirements for Tritium Processing Design and R&D

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

Hollis, William Kirk; Maynard, Sarah-Jane Wadsworth

2015-10-30

This document will address requirements of export control associated with tritium plant design and processes. Los Alamos National Laboratory has been working in the area of tritium plant system design and research and development (R&D) since the early 1970’s at the Tritium Systems Test Assembly (TSTA). This work has continued to the current date with projects associated with the ITER project and other Office of Science Fusion Energy Science (OS-FES) funded programs. ITER is currently the highest funding area for the DOE OS-FES. Although export control issues have been integrated into these projects in the past a general guidance documentmore » has not been available for reference in this area. To address concerns with currently funded tritium plant programs and assist future projects for FES, this document will identify the key reference documents and specific sections within related to tritium research. Guidance as to the application of these sections will be discussed with specific detail to publications and work with foreign nationals.« less

New calculations of gross β-decay properties for astrophysical applications: Speeding-up the classical r process

NASA Astrophysics Data System (ADS)

Möller, Peter; Pfeiffer, Bernd; Kratz, Karl-Ludwig

2003-05-01

Recent compilations of experimental gross β-decay properties, i.e., half-lives (T1/2) and neutron-emission probabilities (Pn), are compared to improved global macroscopic-microscopic model predictions. The model combines calculations within the quasiparticle (QP) random-phase approximation for the Gamow-Teller (GT) part with an empirical spreading of the QP strength and the gross theory for the first-forbidden part of β- decay. Nuclear masses are either taken from the 1995 data compilation of Audi et al., when available, otherwise from the finite-range droplet model. Especially for spherical and neutron-(sub-)magic isotopes a considerable improvement compared to our earlier predictions for pure GT decay (ADNDT, 1997) is observed. T1/2 and Pn values up to the neutron drip line have been used in r-process calculations within the classical “waiting-point” approximation. With the new nuclear-physics input, a considerable speeding-up of the r-matter flow is observed, in particular at those r-abundance peaks which are related to magic neutron-shell closures.

The r-Java 2.0 code: nuclear physics

NASA Astrophysics Data System (ADS)

Kostka, M.; Koning, N.; Shand, Z.; Ouyed, R.; Jaikumar, P.

2014-08-01

Aims: We present r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations, along with a suite of other analysis tools. Methods: Equipped with a straightforward graphical user interface, r-Java 2.0 is capable of simulating nuclear statistical equilibrium (NSE), calculating r-process abundances for a wide range of input parameters and astrophysical environments, computing the mass fragmentation from neutron-induced fission and studying individual nucleosynthesis processes. Results: In this paper we discuss enhancements to this version of r-Java, especially the ability to solve the full reaction network. The sophisticated fission methodology incorporated in r-Java 2.0 that includes three fission channels (beta-delayed, neutron-induced, and spontaneous fission), along with computation of the mass fragmentation, is compared to the upper limit on mass fission approximation. The effects of including beta-delayed neutron emission on r-process yield is studied. The role of Coulomb interactions in NSE abundances is shown to be significant, supporting previous findings. A comparative analysis was undertaken during the development of r-Java 2.0 whereby we reproduced the results found in the literature from three other r-process codes. This code is capable of simulating the physical environment of the high-entropy wind around a proto-neutron star, the ejecta from a neutron star merger, or the relativistic ejecta from a quark nova. Likewise the users of r-Java 2.0 are given the freedom to define a custom environment. This software provides a platform for comparing proposed r-process sites.

β-decay spectroscopy of r-process nuclei with N = 126 at KISS

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

Hirayama, Y.; Watanabe, Y. X.; Imai, N.

2014-05-02

The β-decay properties of nuclei with N = 126, which are believed to act as progenitors in the rapid neutron capture (r-) process path forming the third peak (A ∼ 195) in the observed r-abundance element distribution, are considered critical for understanding the production of heavy elements such as gold and platinum at astrophysical sites. We have constructed the KEK Isotope Separation System (KISS), which consists of a gas cell based laser ion source (atomic number selection) and an isotope separation on-line (ISOL) (mass number selection), to produce pure low-energy beams of neutron-rich isotopes around N = 126 and tomore » study their β-decay properties, which are also of interest for astrophysics. The isotopes of interest will be produced by multi-nucleon transfer reactions in heavy ion collisions (e.g. {sup 136}Xe projectile on {sup 198}Pt target). KISS will allow us to study unknown isotopes produced in weak reaction channels under low background conditions. We successfully extracted the stable {sup 56}Fe beam from KISS at the last commissioning on-line experiment with the extraction efficiency of 0.25% and beam purity of more than 98%. We can access the nuclei with N = 126 and measure their half-lives using the KISS in the case of the extraction efficiency of 0.1%.« less

eddy4R 0.2.0: a DevOps model for community-extensible processing and analysis of eddy-covariance data based on R, Git, Docker, and HDF5

NASA Astrophysics Data System (ADS)

Metzger, Stefan; Durden, David; Sturtevant, Cove; Luo, Hongyan; Pingintha-Durden, Natchaya; Sachs, Torsten; Serafimovich, Andrei; Hartmann, Jörg; Li, Jiahong; Xu, Ke; Desai, Ankur R.

2017-08-01

Large differences in instrumentation, site setup, data format, and operating system stymie the adoption of a universal computational environment for processing and analyzing eddy-covariance (EC) data. This results in limited software applicability and extensibility in addition to often substantial inconsistencies in flux estimates. Addressing these concerns, this paper presents the systematic development of portable, reproducible, and extensible EC software achieved by adopting a development and systems operation (DevOps) approach. This software development model is used for the creation of the eddy4R family of EC code packages in the open-source R language for statistical computing. These packages are community developed, iterated via the Git distributed version control system, and wrapped into a portable and reproducible Docker filesystem that is independent of the underlying host operating system. The HDF5 hierarchical data format then provides a streamlined mechanism for highly compressed and fully self-documented data ingest and output. The usefulness of the DevOps approach was evaluated for three test applications. First, the resultant EC processing software was used to analyze standard flux tower data from the first EC instruments installed at a National Ecological Observatory (NEON) field site. Second, through an aircraft test application, we demonstrate the modular extensibility of eddy4R to analyze EC data from other platforms. Third, an intercomparison with commercial-grade software showed excellent agreement (R2 = 1.0 for CO2 flux). In conjunction with this study, a Docker image containing the first two eddy4R packages and an executable example workflow, as well as first NEON EC data products are released publicly. We conclude by describing the work remaining to arrive at the automated generation of science-grade EC fluxes and benefits to the science community at large. This software development model is applicable beyond EC and more generally builds

Evaluation of different signal processing options in unilateral and bilateral cochlear freedom implant recipients using R-Space background noise.

PubMed

Brockmeyer, Alison M; Potts, Lisa G

2011-02-01

Difficulty understanding in background noise is a common complaint of cochlear implant (CI) recipients. Programming options are available to improve speech recognition in noise for CI users including automatic dynamic range optimization (ADRO), autosensitivity control (ASC), and a two-stage adaptive beamforming algorithm (BEAM). However, the processing option that results in the best speech recognition in noise is unknown. In addition, laboratory measures of these processing options often show greater degrees of improvement than reported by participants in everyday listening situations. To address this issue, Compton-Conley and colleagues developed a test system to replicate a restaurant environment. The R-SPACE™ consists of eight loudspeakers positioned in a 360 degree arc and utilizes a recording made at a restaurant of background noise. The present study measured speech recognition in the R-SPACE with four processing options: standard dual-port directional (STD), ADRO, ASC, and BEAM. A repeated-measures, within-subject design was used to evaluate the four different processing options at two noise levels. Twenty-seven unilateral and three bilateral adult Nucleus Freedom CI recipients. The participants' everyday program (with no additional processing) was used as the STD program. ADRO, ASC, and BEAM were added individually to the STD program to create a total of four programs. Participants repeated Hearing in Noise Test sentences presented at 0 degrees azimuth with R-SPACE restaurant noise at two noise levels, 60 and 70 dB SPL. The reception threshold for sentences (RTS) was obtained for each processing condition and noise level. In 60 dB SPL noise, BEAM processing resulted in the best RTS, with a significant improvement over STD and ADRO processing. In 70 dB SPL noise, ASC and BEAM processing had significantly better mean RTSs compared to STD and ADRO processing. Comparison of noise levels showed that STD and BEAM processing resulted in significantly poorer

Uranium lines in the spectra of peculiar A stars - A search for recent r-process events

NASA Technical Reports Server (NTRS)

Cowley, C. R.; Adelman, S. J.

1975-01-01

Uranium wavelengths in the spectra of Ap stars are studied to see if they give any indication of a recent r-process event. It is concluded that there is no credible evidence for an admixture of uranium-235 in these stars, which would imply such an event. The evidence, though negative, is badly confused by blending of lines, and a final judgement must wait for an observational clarification of the situation.

Aggregation of Ribosomal Protein S6 at Nucleolus Is Cell Cycle-Controlled and Its Function in Pre-rRNA Processing Is Phosphorylation Dependent.

PubMed

Zhang, Duo; Chen, Hui-Peng; Duan, Hai-Feng; Gao, Li-Hua; Shao, Yong; Chen, Ke-Yan; Wang, You-Liang; Lan, Feng-Hua; Hu, Xian-Wen

2016-07-01

Ribosomal protein S6 (rpS6) has long been regarded as one of the primary r-proteins that functions in the early stage of 40S subunit assembly, but its actual role is still obscure. The correct forming of 18S rRNA is a key step in the nuclear synthesis of 40S subunit. In this study, we demonstrate that rpS6 participates in the processing of 30S pre-rRNA to 18S rRNA only when its C-terminal five serines are phosphorylated, however, the process of entering the nucleus and then targeting the nucleolus does not dependent its phosphorylation. Remarkably, we also find that the aggregation of rpS6 at the nucleolus correlates to the phasing of cell cycle, beginning to concentrate in the nucleolus at later S phase and disaggregate at M phase. J. Cell. Biochem. 117: 1649-1657, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Signatures of hypermassive neutron star lifetimes on r-process nucleosynthesis in the disc ejecta from neutron star mergers

NASA Astrophysics Data System (ADS)

Lippuner, Jonas; Fernández, Rodrigo; Roberts, Luke F.; Foucart, Francois; Kasen, Daniel; Metzger, Brian D.; Ott, Christian D.

2017-11-01

We investigate the nucleosynthesis of heavy elements in the winds ejected by accretion discs formed in neutron star mergers. We compute the element formation in disc outflows from hypermassive neutron star (HMNS) remnants of variable lifetime, including the effect of angular momentum transport in the disc evolution. We employ long-term axisymmetric hydrodynamic disc simulations to model the ejecta, and compute r-process nucleosynthesis with tracer particles using a nuclear reaction network containing ∼8000 species. We find that the previously known strong correlation between HMNS lifetime, ejected mass and average electron fraction in the outflow is directly related to the amount of neutrino irradiation on the disc, which dominates mass ejection at early times in the form of a neutrino-driven wind. Production of lanthanides and actinides saturates at short HMNS lifetimes (≲10 ms), with additional ejecta contributing to a blue optical kilonova component for longer-lived HMNSs. We find good agreement between the abundances from the disc outflow alone and the solar r-process distribution only for short HMNS lifetimes (≲10 ms). For longer lifetimes, the rare-earth and third r-process peaks are significantly underproduced compared to the solar pattern, requiring additional contributions from the dynamical ejecta. The nucleosynthesis signature from a spinning black hole (BH) can only overlap with that from an HMNS of moderate lifetime (≲60 ms). Finally, we show that angular momentum transport not only contributes with a late-time outflow component, but that it also enhances the neutrino-driven component by moving material to shallower regions of the gravitational potential, in addition to providing additional heating.

GOES-R Encapsulation

NASA Image and Video Library

2016-10-21

Team members with United Launch Alliance (ULA) prepare the Geostationary Operational Environmental Satellite (GOES-R) for encapsulation in the payload fairing inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

GOES-R Encapsulation

NASA Image and Video Library

2016-10-21

The two halves of the payload fairing are fully closed around the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Implications of the {{\\boldsymbol{R}}}_{K} and {{\\boldsymbol{R}}}_{{K}^{* }} anomalies

NASA Astrophysics Data System (ADS)

Wang, Wei; Zhao, Shuai

2018-01-01

We discuss the implications of the recently reported {R}{{K}} and {R}{{{K}}* } anomalies, the lepton flavor non-universality in the {{B}}\\to {Kl}}+{{{l}}}- and {{B}}\\to {{{K}}}* {{{l}}}+{{{l}}}- decay channels. Using two sets of hadronic inputs of form factors, we perform a fit of new physics to the {R}{{K}} and {R}{{{K}}* } data, and significant new physics contributions are found. We suggest the study of lepton flavor universality in a number of related rare {{B}},{{{B}}}s,{{{B}}}c and {{{Λ }}}{{b}} decay channels, and in particular we give predictions for the {{μ }}-to-e ratios of decay widths with different polarizations of the final state particles, and of the {{b}}\\to {dl}}+{{{l}}}- processes, which are presumably more sensitive to the structure of the underlying new physics. With the new physics contributions embedded in the Wilson coefficients, we present theoretical predictions for lepton flavor non-universality in these processes. Supported by National Natural Science Foundation of China (11575110, 11655002, 11735010), Natural Science Foundation of Shanghai (15DZ2272100, 15ZR1423100), Young Thousand Talents Plan and Key Laboratory for Particle Physics, Astrophysics and Cosmology, Ministry of Education

RSEIS and RFOC: Seismic Analysis in R

NASA Astrophysics Data System (ADS)

Lees, J. M.

2015-12-01

Open software is essential for reproducible scientific exchange. R-packages provide a platform for development of seismological investigation software that can be properly documented and traced for data processing. A suite of R packages designed for a wide range of seismic analysis is currently available in the free software platform called R. R is a software platform based on the S-language developed at Bell Labs decades ago. Routines in R can be run as standalone function calls, or developed in object-oriented mode. R comes with a base set of routines, and thousands of user developed packages. The packages developed at UNC include subroutines and interactive codes for processing seismic data, analyzing geographic information (GIS) and inverting data involved in a variety of geophysical applications. On CRAN (Comprehensive R Archive Network, http://www.r-project.org/) currently available packages related to seismic analysis are RSEIS, Rquake, GEOmap, RFOC, zoeppritz, RTOMO, and geophys, Rwave, PEIP, hht, rFDSN. These include signal processing, data management, mapping, earthquake location, deconvolution, focal mechanisms, wavelet transforms, Hilbert-Huang Transforms, tomographic inversion, and Mogi deformation among other useful functionality. All software in R packages is required to have detailed documentation, making the exchange and modification of existing software easy. In this presentation, I will focus on packages RSEIS and RFOC, showing examples from a variety of seismic analyses. The R approach has similarities to the popular (and expensive) MATLAB platform, although R is open source and free to down load.

Intrusive [r] and Optimal Epenthetic Consonants

ERIC Educational Resources Information Center

Uffmann, Christian

2007-01-01

This paper argues against the view of intrusive [r] as a synchronically arbitrary insertion process. Instead, it is seen as a phonologically natural process, which can be modelled within the framework of Optimality Theory (OT). Insertion of [r] in phonologically restricted environments is a consequence of a more general theory of consonant…

Full scale implementation of the nutrient limited BAS process at Södra Cell Värö.

PubMed

Malmqvist, A; Berggren, B; Sjölin, C; Welander, T; Heuts, L; Fransén, A; Ling, D

2004-01-01

A combination of the suspended carrier biofilm process and the activated sludge process (biofilm-activated sludge--BAS) has been shown to be very successful for the treatment of different types of pulp and paper mill effluents. The robust biofilm pre-treatment in combination with activated sludge results in a stable, compact and highly efficient process. Recent findings have shown that nutrient limited operation of the biofilm process greatly improves the sludge characteristics in the following activated sludge stage, while minimising sludge production and effluent discharge of nutrients. The nutrient limited BAS process was implemented at full scale at the Södra Cell Värö kraft mill and taken into operation in July 2002. After start-up and optimisation over about 5 months, the process meets all effluent discharge limits. The removal of COD is close to 70% and the removal of EDTA greater than 90%. Typical effluent concentrations of suspended solids and nutrients during stable operations have been 20-30 mg/L TSS, 0.3-0.5 mg/L phosphorus and 3-5 mg/L nitrogen. The sludge production was 0.09 kgSS/kg COD removed and the sludge volume index was 50-100 mL/g.

GOES-R Encapsulation

NASA Image and Video Library

2016-10-21

Team members with United Launch Alliance (ULA) monitor the progress as the two halves of the payload fairing close around the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

The nucleotide sequence of the intergenic region between the 5.8S and 26S rRNA genes of the yeast ribosomal RNA operon. Possible implications for the interaction between 5.8S and 26S rRNA and the processing of the primary transcript.

PubMed Central

Veldman, G M; Klootwijk, J; van Heerikhuizen, H; Planta, R J

1981-01-01

We have determined the nucleotide sequence of part of a cloned yeast ribosomal RNA operon extending from the 5.8S RNA gene downstream into the 5' -terminal region of the 26S RNA gene. We mapped the pertinent processing sites, viz. the 5' end of 26S rRNA and the 3'ends of 5.8S rRNA and its immediate precursor, 7S RNA. At the 3' end of 7S RNA we find the sequence UCGUUU which is very similar to the type I consensus sequence UCAUUA/U present at the 3' ends of 17S, 5.8S and 26S rRNA as well as 18S precursor rRNA in yeast. At the 5' end of the 26S RNA gene we find a sequence of thirteen nucleotides which is homologous to the type II sequence present at the 5' termini of both the 17S and the 5.8S RNA gene. These findings further support the suggestion put forward earlier (G.M. Veldman et al. (1980) Nucl. Acids Res. 8, 2907-2920) that both consensus sequences are involved in the recognition of precursor rRNA by the processing nuclease(s). We discuss a model for the processing of yeast rRNA in which a processing enzyme sequentially recognizes several combinations of a type I and a type II consensus sequence. We also describe the existence of a significant base complementarity between sequences in the 5' -terminal region of 26S rRNA and the 3' -terminal region of 5.8S rRNA. We suggest that base pairing between these sequences contributes to the binding between 5.8S and 26S rRNA. Images PMID:7312619

77 FR 1656 - Proposed Establishment of Restricted Areas R-5402, R-5403A, R-5403B, R-5403C, R-5403D, R-5403E, R...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-11

...-0117; Airspace Docket No. 09-AGL-31] RIN 2120-AI92 Proposed Establishment of Restricted Areas R-5402, R-5403A, R- 5403B, R-5403C, R-5403D, R-5403E, R-5403F; Devils Lake, ND AGENCY: Federal Aviation... Restricted Areas R-5402, R-5403A, R-5403B, R- 5403C, R-5403D, R-5403E, R-5403F; Devils Lake, ND (76 FR 72869...

GOES-R Encapsulation

NASA Image and Video Library

2016-10-21

Team members with United Launch Alliance (ULA) monitor the progress as the two halves of the payload fairing begin to close around the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

SARTools: A DESeq2- and EdgeR-Based R Pipeline for Comprehensive Differential Analysis of RNA-Seq Data.

PubMed

Varet, Hugo; Brillet-Guéguen, Loraine; Coppée, Jean-Yves; Dillies, Marie-Agnès

2016-01-01

Several R packages exist for the detection of differentially expressed genes from RNA-Seq data. The analysis process includes three main steps, namely normalization, dispersion estimation and test for differential expression. Quality control steps along this process are recommended but not mandatory, and failing to check the characteristics of the dataset may lead to spurious results. In addition, normalization methods and statistical models are not exchangeable across the packages without adequate transformations the users are often not aware of. Thus, dedicated analysis pipelines are needed to include systematic quality control steps and prevent errors from misusing the proposed methods. SARTools is an R pipeline for differential analysis of RNA-Seq count data. It can handle designs involving two or more conditions of a single biological factor with or without a blocking factor (such as a batch effect or a sample pairing). It is based on DESeq2 and edgeR and is composed of an R package and two R script templates (for DESeq2 and edgeR respectively). Tuning a small number of parameters and executing one of the R scripts, users have access to the full results of the analysis, including lists of differentially expressed genes and a HTML report that (i) displays diagnostic plots for quality control and model hypotheses checking and (ii) keeps track of the whole analysis process, parameter values and versions of the R packages used. SARTools provides systematic quality controls of the dataset as well as diagnostic plots that help to tune the model parameters. It gives access to the main parameters of DESeq2 and edgeR and prevents untrained users from misusing some functionalities of both packages. By keeping track of all the parameters of the analysis process it fits the requirements of reproducible research.

The role of the inferior frontal gyri in cognitive processing of patients with Parkinson's disease: a pilot rTMS study.

PubMed

Srovnalova, Hana; Marecek, Radek; Rektorova, Irena

2011-07-01

We studied whether 1 session of high-frequency repetitive transcranial magnetic stimulation (rTMS) applied sequentially over both the left and right inferior frontal gyri (IFG) would enhance performance in tests evaluating the ability to inhibit habitual responses (Stroop test, ST; Frontal Assessment Battery, FAB) in patients with Parkinson's disease (PD). Ten nondemented PD patients (6 men, 4 women; age, 66 ± 6 years; disease duration, 5.4 ± 2.45 years) entered the randomized, sham stimulation-controlled study with a crossover design. The ST and the FAB were performed prior to and immediately after an appropriate rTMS session. The active but not sham rTMS induced significant improvement in all ST subtests (word, color, color-word). Conversely, the calculated Stroop interference and the FAB scores remained unchanged. In PD patients, rTMS of the IFG increased the speed of cognitive processing in both the congruent and incongruent conditions of the ST. Copyright © 2011 Movement Disorder Society.

Scater: pre-processing, quality control, normalization and visualization of single-cell RNA-seq data in R.

PubMed

McCarthy, Davis J; Campbell, Kieran R; Lun, Aaron T L; Wills, Quin F

2017-04-15

Single-cell RNA sequencing (scRNA-seq) is increasingly used to study gene expression at the level of individual cells. However, preparing raw sequence data for further analysis is not a straightforward process. Biases, artifacts and other sources of unwanted variation are present in the data, requiring substantial time and effort to be spent on pre-processing, quality control (QC) and normalization. We have developed the R/Bioconductor package scater to facilitate rigorous pre-processing, quality control, normalization and visualization of scRNA-seq data. The package provides a convenient, flexible workflow to process raw sequencing reads into a high-quality expression dataset ready for downstream analysis. scater provides a rich suite of plotting tools for single-cell data and a flexible data structure that is compatible with existing tools and can be used as infrastructure for future software development. The open-source code, along with installation instructions, vignettes and case studies, is available through Bioconductor at http://bioconductor.org/packages/scater . davis@ebi.ac.uk. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

Yeast polypeptide exit tunnel ribosomal proteins L17, L35 and L37 are necessary to recruit late-assembling factors required for 27SB pre-rRNA processing.

PubMed

Gamalinda, Michael; Jakovljevic, Jelena; Babiano, Reyes; Talkish, Jason; de la Cruz, Jesús; Woolford, John L

2013-02-01

Ribosome synthesis involves the coordinated folding and processing of pre-rRNAs with assembly of ribosomal proteins. In eukaryotes, these events are facilitated by trans-acting factors that propel ribosome maturation from the nucleolus to the cytoplasm. However, there is a gap in understanding how ribosomal proteins configure pre-ribosomes in vivo to enable processing to occur. Here, we have examined the role of adjacent yeast r-proteins L17, L35 and L37 in folding and processing of pre-rRNAs, and binding of other proteins within assembling ribosomes. These three essential ribosomal proteins, which surround the polypeptide exit tunnel, are required for 60S subunit formation as a consequence of their role in removal of the ITS2 spacer from 27SB pre-rRNA. L17-, L35- and L37-depleted cells exhibit turnover of aberrant pre-60S assembly intermediates. Although the structure of ITS2 does not appear to be grossly affected in their absence, these three ribosomal proteins are necessary for efficient recruitment of factors required for 27SB pre-rRNA processing, namely, Nsa2 and Nog2, which associate with pre-60S ribosomal particles containing 27SB pre-rRNAs. Altogether, these data support that L17, L35 and L37 are specifically required for a recruiting step immediately preceding removal of ITS2.

Yeast polypeptide exit tunnel ribosomal proteins L17, L35 and L37 are necessary to recruit late-assembling factors required for 27SB pre-rRNA processing

PubMed Central

Gamalinda, Michael; Jakovljevic, Jelena; Babiano, Reyes; Talkish, Jason; de la Cruz, Jesús; Woolford, John L.

2013-01-01

Ribosome synthesis involves the coordinated folding and processing of pre-rRNAs with assembly of ribosomal proteins. In eukaryotes, these events are facilitated by trans-acting factors that propel ribosome maturation from the nucleolus to the cytoplasm. However, there is a gap in understanding how ribosomal proteins configure pre-ribosomes in vivo to enable processing to occur. Here, we have examined the role of adjacent yeast r-proteins L17, L35 and L37 in folding and processing of pre-rRNAs, and binding of other proteins within assembling ribosomes. These three essential ribosomal proteins, which surround the polypeptide exit tunnel, are required for 60S subunit formation as a consequence of their role in removal of the ITS2 spacer from 27SB pre-rRNA. L17-, L35- and L37-depleted cells exhibit turnover of aberrant pre-60S assembly intermediates. Although the structure of ITS2 does not appear to be grossly affected in their absence, these three ribosomal proteins are necessary for efficient recruitment of factors required for 27SB pre-rRNA processing, namely, Nsa2 and Nog2, which associate with pre-60S ribosomal particles containing 27SB pre-rRNAs. Altogether, these data support that L17, L35 and L37 are specifically required for a recruiting step immediately preceding removal of ITS2. PMID:23268442

Three-Dimensional General-Relativistic Magnetohydrodynamic Simulations of Remnant Accretion Disks from Neutron Star Mergers: Outflows and r -Process Nucleosynthesis

NASA Astrophysics Data System (ADS)

Siegel, Daniel M.; Metzger, Brian D.

2017-12-01

The merger of binary neutron stars, or of a neutron star and a stellar-mass black hole, can result in the formation of a massive rotating torus around a spinning black hole. In addition to providing collimating media for γ -ray burst jets, unbound outflows from these disks are an important source of mass ejection and rapid neutron capture (r -process) nucleosynthesis. We present the first three-dimensional general-relativistic magnetohydrodynamic (GRMHD) simulations of neutrino-cooled accretion disks in neutron star mergers, including a realistic equation of state valid at low densities and temperatures, self-consistent evolution of the electron fraction, and neutrino cooling through an approximate leakage scheme. After initial magnetic field amplification by magnetic winding, we witness the vigorous onset of turbulence driven by the magnetorotational instability (MRI). The disk quickly reaches a balance between heating from MRI-driven turbulence and neutrino cooling, which regulates the midplane electron fraction to a low equilibrium value Ye≈0.1 . Over the 380-ms duration of the simulation, we find that a fraction ≈20 % of the initial torus mass is unbound in powerful outflows with asymptotic velocities v ≈0.1 c and electron fractions Ye≈0.1 - 0.25 . Postprocessing the outflows through a nuclear reaction network shows the production of a robust second- and third-peak r process. Though broadly consistent with the results of previous axisymmetric hydrodynamical simulations, extrapolation of our results to late times suggests that the total ejecta mass from GRMHD disks is significantly higher. Our results provide strong evidence that postmerger disk outflows are an important site for the r process.

Three-Dimensional General-Relativistic Magnetohydrodynamic Simulations of Remnant Accretion Disks from Neutron Star Mergers: Outflows and r-Process Nucleosynthesis.

PubMed

Siegel, Daniel M; Metzger, Brian D

2017-12-08

The merger of binary neutron stars, or of a neutron star and a stellar-mass black hole, can result in the formation of a massive rotating torus around a spinning black hole. In addition to providing collimating media for γ-ray burst jets, unbound outflows from these disks are an important source of mass ejection and rapid neutron capture (r-process) nucleosynthesis. We present the first three-dimensional general-relativistic magnetohydrodynamic (GRMHD) simulations of neutrino-cooled accretion disks in neutron star mergers, including a realistic equation of state valid at low densities and temperatures, self-consistent evolution of the electron fraction, and neutrino cooling through an approximate leakage scheme. After initial magnetic field amplification by magnetic winding, we witness the vigorous onset of turbulence driven by the magnetorotational instability (MRI). The disk quickly reaches a balance between heating from MRI-driven turbulence and neutrino cooling, which regulates the midplane electron fraction to a low equilibrium value Y_{e}≈0.1. Over the 380-ms duration of the simulation, we find that a fraction ≈20% of the initial torus mass is unbound in powerful outflows with asymptotic velocities v≈0.1c and electron fractions Y_{e}≈0.1-0.25. Postprocessing the outflows through a nuclear reaction network shows the production of a robust second- and third-peak r process. Though broadly consistent with the results of previous axisymmetric hydrodynamical simulations, extrapolation of our results to late times suggests that the total ejecta mass from GRMHD disks is significantly higher. Our results provide strong evidence that postmerger disk outflows are an important site for the r process.

miR319, miR390, and miR393 Are Involved in Aluminum Response in Flax (Linum usitatissimum L.).

PubMed

Dmitriev, Alexey A; Kudryavtseva, Anna V; Bolsheva, Nadezhda L; Zyablitsin, Alexander V; Rozhmina, Tatiana A; Kishlyan, Natalya V; Krasnov, George S; Speranskaya, Anna S; Krinitsina, Anastasia A; Sadritdinova, Asiya F; Snezhkina, Anastasiya V; Fedorova, Maria S; Yurkevich, Olga Yu; Muravenko, Olga V; Belenikin, Maxim S; Melnikova, Nataliya V

2017-01-01

Acid soils limit agricultural production worldwide. Major reason of crop losses in acid soils is the toxicity of aluminum (Al). In the present work, we investigated expression alterations of microRNAs in flax ( Linum usitatissimum L.) plants under Al stress. Flax seedlings of resistant (TMP1919 and G1071/4_k) and sensitive (Lira and G1071/4_o) to Al cultivars and lines were exposed to AlCl 3 solution for 4 and 24 hours. Twelve small RNA libraries were constructed and sequenced using Illumina platform. In total, 97 microRNAs from 18 conserved families were identified. miR319, miR390, and miR393 revealed expression alterations associated with Al treatment of flax plants. Moreover, for miR390 and miR393, the alterations were distinct in sensitive and resistant to Al genotypes. Expression level changes of miR319 and miR390 were confirmed using qPCR analysis. In flax, potential targets of miR319 are TCPs, miR390-TAS3 and GRF5, and miR393-AFB2-coding transcripts. TCPs, TAS3, GRF5, and AFB2 participate in regulation of plant growth and development. The involvement of miR319, miR390, and miR393 in response to Al stress in flax was shown here for the first time. We speculate that these microRNAs play an important role in Al response via regulation of growth processes in flax plants.

Quorum Sensing Gene Regulation by LuxR/HapR Master Regulators in Vibrios

PubMed Central

Ball, Alyssa S.; Chaparian, Ryan R.

2017-01-01

ABSTRACT The coordination of group behaviors in bacteria is accomplished via the cell-cell signaling process called quorum sensing. Vibrios have historically been models for studying bacterial communication due to the diverse and remarkable behaviors controlled by quorum sensing in these bacteria, including bioluminescence, type III and type VI secretion, biofilm formation, and motility. Here, we discuss the Vibrio LuxR/HapR family of proteins, the master global transcription factors that direct downstream gene expression in response to changes in cell density. These proteins are structurally similar to TetR transcription factors but exhibit distinct biochemical and genetic features from TetR that determine their regulatory influence on the quorum sensing gene network. We review here the gene groups regulated by LuxR/HapR and quorum sensing and explore the targets that are common and unique among Vibrio species. PMID:28484045

R-HyMOD: an R-package for the hydrological model HyMOD

NASA Astrophysics Data System (ADS)

Baratti, Emanuele; Montanari, Alberto

2015-04-01

A software code for the implementation of the HyMOD hydrological model [1] is presented. HyMOD is a conceptual lumped rainfall-runoff model that is based on the probability-distributed soil storage capacity principle introduced by R. J. Moore 1985 [2]. The general idea behind this model is to describe the spatial variability of some process parameters as, for instance, the soil structure or the water storage capacities, through probability distribution functions. In HyMOD, the rainfall-runoff process is represented through a nonlinear tank connected with three identical linear tanks in parallel representing the surface flow and a slow-flow tank representing groundwater flow. The model requires the optimization of five parameters: Cmax (the maximum storage capacity within the watershed), β (the degree of spatial variability of the soil moisture capacity within the watershed), α (a factor for partitioning the flow between two series of tanks) and the two residence time parameters of quick-flow and slow-flow tanks, kquick and kslow respectively. Given its relatively simplicity but robustness, the model is widely used in the literature. The input data consist of precipitation and potential evapotranspiration at the given time scale. The R-HyMOD package is composed by a 'canonical' R-function of HyMOD and a fast FORTRAN implementation. The first one can be easily modified and can be used, for instance, for educational purposes; the second part combines the R user friendly interface with a fast processing unit. [1] Boyle D.P. (2000), Multicriteria calibration of hydrological models, Ph.D. dissertation, Dep. of Hydrol. and Water Resour., Univ of Arizona, Tucson. [2] Moore, R.J., (1985), The probability-distributed principle and runoff production at point and basin scale, Hydrol. Sci. J., 30(2), 273-297.

IMNGS: A comprehensive open resource of processed 16S rRNA microbial profiles for ecology and diversity studies.

PubMed

Lagkouvardos, Ilias; Joseph, Divya; Kapfhammer, Martin; Giritli, Sabahattin; Horn, Matthias; Haller, Dirk; Clavel, Thomas

2016-09-23

The SRA (Sequence Read Archive) serves as primary depository for massive amounts of Next Generation Sequencing data, and currently host over 100,000 16S rRNA gene amplicon-based microbial profiles from various host habitats and environments. This number is increasing rapidly and there is a dire need for approaches to utilize this pool of knowledge. Here we created IMNGS (Integrated Microbial Next Generation Sequencing), an innovative platform that uniformly and systematically screens for and processes all prokaryotic 16S rRNA gene amplicon datasets available in SRA and uses them to build sample-specific sequence databases and OTU-based profiles. Via a web interface, this integrative sequence resource can easily be queried by users. We show examples of how the approach allows testing the ecological importance of specific microorganisms in different hosts or ecosystems, and performing targeted diversity studies for selected taxonomic groups. The platform also offers a complete workflow for de novo analysis of users' own raw 16S rRNA gene amplicon datasets for the sake of comparison with existing data. IMNGS can be accessed at www.imngs.org.

miR319, miR390, and miR393 Are Involved in Aluminum Response in Flax (Linum usitatissimum L.)

PubMed Central

Zyablitsin, Alexander V.; Rozhmina, Tatiana A.; Speranskaya, Anna S.; Sadritdinova, Asiya F.

2017-01-01

Acid soils limit agricultural production worldwide. Major reason of crop losses in acid soils is the toxicity of aluminum (Al). In the present work, we investigated expression alterations of microRNAs in flax (Linum usitatissimum L.) plants under Al stress. Flax seedlings of resistant (TMP1919 and G1071/4_k) and sensitive (Lira and G1071/4_o) to Al cultivars and lines were exposed to AlCl3 solution for 4 and 24 hours. Twelve small RNA libraries were constructed and sequenced using Illumina platform. In total, 97 microRNAs from 18 conserved families were identified. miR319, miR390, and miR393 revealed expression alterations associated with Al treatment of flax plants. Moreover, for miR390 and miR393, the alterations were distinct in sensitive and resistant to Al genotypes. Expression level changes of miR319 and miR390 were confirmed using qPCR analysis. In flax, potential targets of miR319 are TCPs, miR390–TAS3 and GRF5, and miR393–AFB2-coding transcripts. TCPs, TAS3, GRF5, and AFB2 participate in regulation of plant growth and development. The involvement of miR319, miR390, and miR393 in response to Al stress in flax was shown here for the first time. We speculate that these microRNAs play an important role in Al response via regulation of growth processes in flax plants. PMID:28299328

A Goal Programming R&D (Research and Development) Project Funding Model of the U.S. Army Strategic Defense Command Using the Analytic Hierarchy Process.

DTIC Science & Technology

1987-09-01

A187 899 A GOAL PROGRANNIN R&D (RESEARCH AND DEVELOPMENT) 1/2 PROJECT FUNDING MODEL 0 (U) NAVAL POSTGRADUATE SCHOOL MONTEREY CA S M ANDERSON SEP 87...PROGRAMMING R&D PROJECT FUNDING MODEL OF THE U.S. ARMY STRATEGIC DEFENSE COMMAND USING THE ANALYTIC HIERARCHY PROCESS by Steven M. Anderson September 1987...jACCESSION NO TITI E (Influde Securt ClauAIcatsrn) A Goal Programming R&D Project Funding Model of the U.S. Army Strategic Defense Command Using the

Evolution of rDNA in Nicotiana Allopolyploids: A Potential Link between rDNA Homogenization and Epigenetics

PubMed Central

Kovarik, Ales; Dadejova, Martina; Lim, Yoong K.; Chase, Mark W.; Clarkson, James J.; Knapp, Sandra; Leitch, Andrew R.

2008-01-01

Background The evolution and biology of rDNA have interested biologists for many years, in part, because of two intriguing processes: (1) nucleolar dominance and (2) sequence homogenization. We review patterns of evolution in rDNA in the angiosperm genus Nicotiana to determine consequences of allopolyploidy on these processes. Scope Allopolyploid species of Nicotiana are ideal for studying rDNA evolution because phylogenetic reconstruction of DNA sequences has revealed patterns of species divergence and their parents. From these studies we also know that polyploids formed over widely different timeframes (thousands to millions of years), enabling comparative and temporal studies of rDNA structure, activity and chromosomal distribution. In addition studies on synthetic polyploids enable the consequences of de novo polyploidy on rDNA activity to be determined. Conclusions We propose that rDNA epigenetic expression patterns established even in F1 hybrids have a material influence on the likely patterns of divergence of rDNA. It is the active rDNA units that are vulnerable to homogenization, which probably acts to reduce mutational load across the active array. Those rDNA units that are epigenetically silenced may be less vulnerable to sequence homogenization. Selection cannot act on these silenced genes, and they are likely to accumulate mutations and eventually be eliminated from the genome. It is likely that whole silenced arrays will be deleted in polyploids of 1 million years of age and older. PMID:18310159

GOES-R Fairing Inspection

NASA Image and Video Library

2016-09-26

Team members with United Launch Alliance (ULA) inspect the first half of the fairing for the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

STAT3-regulated exosomal miR-21 promotes angiogenesis and is involved in neoplastic processes of transformed human bronchial epithelial cells.

PubMed

Liu, Yi; Luo, Fei; Wang, Bairu; Li, Huiqiao; Xu, Yuan; Liu, Xinlu; Shi, Le; Lu, Xiaolin; Xu, Wenchao; Lu, Lu; Qin, Yu; Xiang, Quanyong; Liu, Qizhan

2016-01-01

Although microRNA (miRNA) enclosed in exosomes can mediate intercellular communication, the roles of exosomal miRNA and angiogenesis in lung cancer remain unclear. We investigated functions of STAT3-regulated exosomal miR-21 derived from cigarette smoke extract (CSE)-transformed human bronchial epithelial (HBE) cells in the angiogenesis of CSE-induced carcinogenesis. miR-21 levels in serum were higher in smokers than those in non-smokers. The medium from transformed HBE cells promoted miR-21 levels in normal HBE cells and angiogenesis of human umbilical vein endothelial cells (HUVEC). Transformed cells transferred miR-21 into normal HBE cells via exosomes. Knockdown of STAT3 reduced miR-21 levels in exosomes derived from transformed HBE cells, which blocked the angiogenesis. Exosomes derived from transformed HBE cells elevated levels of vascular endothelial growth factor (VEGF) in HBE cells and thereby promoted angiogenesis in HUVEC cells. Inhibition of exosomal miR-21, however, decreased VEGF levels in recipient cells, which blocked exosome-induced angiogenesis. Thus, miR-21 in exosomes leads to STAT3 activation, which increases VEGF levels in recipient cells, a process involved in angiogenesis and malignant transformation of HBE cells. These results, demonstrating the function of exosomal miR-21 from transformed HBE cells, provide a new perspective for intervention strategies to prevent carcinogenesis of lung cancer. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Experiments towards establishing of design rules for R2R-UV-NIL with polymer working shims

NASA Astrophysics Data System (ADS)

Nees, Dieter; Ruttloff, Stephan; Palfinger, Ursula; Stadlober, Barbara

2016-03-01

Roll-to-Roll-UV-nanoimprint lithography (R2R-UV-NIL) enables high resolution large area patterning of flexible substrates and is therefore of increasing industrial interest. We have set up a custom-made R2R-UV-NIL pilot machine which is able to convert 10 inch wide web with velocities of up to 30 m/min. In addition, we have developed self-replicable UV-curable resins with tunable surface energy and Young's modulus for UV-imprint material as well as for polymer working stamp/shim manufacturing. Now we have designed test patterns for the evaluation of the impact of structure shape, critical dimension, pitch, depth, side wall angle and orientation relative to the web movement onto the imprint fidelity and working shim life time. We have used female (recessed structures) silicon masters of that design with critical dimensions between CD = 200 nm and 1600 nm, and structure depths of d = 500 nm and 1000 nm - all with vertical as well as inclined side walls. These entire master patterns have been transferred onto single male (protruding structures) R2R polymer working shims. The polymer working shims have been used for R2R-UV-NIL runs of several hundred meters and the imprint fidelity and process stability of the various test patterns have been compared. This study is intended as a first step towards establishing of design rules and developing of nanoimprint proximity correction strategies for industrial R2R-UV-NIL processes using polymer working shims.

The Revised Two-Factor Study Process Questionnaire (R-SPQ-2F): Exploratory and Confirmatory Factor Analyses at Item Level

ERIC Educational Resources Information Center

Justicia, Fernando; Pichardo, M. Carmen; Cano, Francisco; Berben, A. B. G.; De la Fuente, Jesus

2008-01-01

The underlying structure of the Revised Two Factor version of the Study Process Questionnaire (R-SPQ-2F), a 20-item instrument for the evaluation of students' approaches to learning (SAL), was examined at item level using two independent groups of undergraduate students enrolled in the first (n = 314) and last (n = 522) years of their studies. The…

Production of (R)-3-hydroxybutyric acid by fermentation and bioconversion processes with Azohydromonas lata.

PubMed

Ugwu, Charles U; Tokiwa, Yutaka; Ichiba, Toshio

2011-06-01

Feasibility of producing (R)-3-hydroxybutyric acid ((R)-3-HB) using wild type Azohydromonas lata and its mutants (derived by UV mutation) was investigated. A. lata mutant (M5) produced 780 m g/l in the culture broth when sucrose was used as the carbon source. M5 was further studied in terms of its specificity with various bioconversion substrates for production of (R)-3-HB. (R)-3-HB concentration produced in the culture broth by M5 mutant was 2.7-fold higher than that of the wild type strain when sucrose (3% w/v) and (R,S)-1,3-butanediol (3% v/v) were used as carbon source and bioconversion substrate, respectively. Bioconversion of resting cells (M5) with glucose (1% v/w), ethylacetoacetate (2% v/v), and (R,S)-1,3-butanediol (3% v/v), resulted in (R)-3-HB concentrations of 6.5 g/l, 7.3g/l and 8.7 g/l, respectively. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evidence that PC2 is the endogenous pro-neurotensin convertase in rMTC 6-23 cells and that PC1- and PC2-transfected PC12 cells differentially process pro-neurotensin.

PubMed

Rovère, C; Barbero, P; Kitabgi, P

1996-05-10

The neuropeptide precursor proneurotensin/neuromedin N (pro-NT/NN) is mainly expressed and differentially processed in the brain and in the small intestine. We showed previously that rMTC 6-23 cells process pro-NT/NN with a pattern similar to brain tissue and increase pro-NT/NN expression in response to dexamethasone, and that PC12 cells also produce pro-NT/NN but are virtually unable to process it. In addition, PC12 cells were reported to be devoid of the prohormone convertases PC1 and PC2. The present study was designed to identify the proprotein convertase(s) (PC) involved in pro-NT/NN processing in rMTC 6-23 cells and to compare PC1- and PC2-transfected PC12 cells for their ability to process pro-NT/NN. rMTC 6-23 cells were devoid of PC1, PC4, and PC5 but expressed furin and PC2. Stable expression of antisense PC2 RNA in rMTC 6-23 cells led to a 90% decrease in PC2 protein levels that correlated with a > 80% reduction of pro-NT/NN processing. PC2 expression was stimulated by dexamethasone in a time- and concentration-dependent manner. Stable PC12/PC2 transfectants processed pro-NT/NN with a pattern similar to that observed in the brain and in rMTC 6-23 cells. In contrast, stable PC12/PC1 transfectants reproduced the pro-NT/NN processing pattern seen in the gut. We conclude that (i) PC2 is the major pro-NT/NN convertase in rMTC 6-23 cells; (ii) its expression is coregulated with that of pro-NT/NN in this cell line; and (iii) PC2 and PC1 differentially process pro-NT/NN with brain and intestinal phenotype, respectively.

The integration of process R&D in drug discovery--challenges and opportunities.

PubMed

Federsel, Hans-Jürgen

2006-02-01

In today's situation where a lot of attention is put on the whereabouts of the pharmaceutical industry, especially focusing on productivity, pricing policies, time lines, and competition, there is an increased need for a critical revision of work practices in the business. The prevailing prioritization of time-to-market is now more and more shifting over to also put quality, risk management, and effectiveness/efficiency in the limelight. Resources in terms of people and money will continue to be constrained and, therefore, best collaborative principles have to be adopted between different parts of the organization. Only by operating this way will we maximize the output. One of the most important key performance indicators in pharma R&D is the number of newly appointed candidate drugs (CDs). However, it is not only a matter of counting numbers but, more so, to nominate compounds with the best properties and likelihood to survive. In that vein the demands on Process R&D have gone up considerably over recent years and there is now a pronounced need to make forecasts on cost of goods for the API (active pharmaceutical ingredient), scalability issues, IP matters, route design etc. On top of this, there is as always an expectation that the supply of material needed to conduct the various studies is timely, fully reliable, and flexible, even if volumes and delivery dates fluctuate widely. To successfully be able to cope with this challenging and sometimes stressful situation a back-integration into earlier parts of Drug Discovery is a must and, hence, connecting to new projects will have to be initiated already during the LO-stage (lead optimization). The consequences of this and its further implications will constitute the core part of the paper.

Urban RoGeR: Merging process-based high-resolution flash flood model for urban areas with long-term water balance predictions

NASA Astrophysics Data System (ADS)

Weiler, M.

2016-12-01

Heavy rain induced flash floods are still a serious hazard and generate high damages in urban areas. In particular in the spatially complex urban areas, the temporal and spatial pattern of runoff generation processes at a wide spatial range during extreme rainfall events need to be predicted including the specific effects of green infrastructure and urban forests. In addition, the initial conditions (soil moisture pattern, water storage of green infrastructure) and the effect of lateral redistribution of water (run-on effects and re-infiltration) have to be included in order realistically predict flash flood generation. We further developed the distributed, process-based model RoGeR (Runoff Generation Research) to include the relevant features and processes in urban areas in order to test the effects of different settings, initial conditions and the lateral redistribution of water on the predicted flood response. The uncalibrated model RoGeR runs at a spatial resolution of 1*1m² (LiDAR, degree of sealing, landuse), soil properties and geology (1:50.000). In addition, different green infrastructures are included into the model as well as the effect of trees on interception and transpiration. A hydraulic model was included into RoGeR to predict surface runoff, water redistribution, and re-infiltration. During rainfall events, RoGeR predicts at 5 min temporal resolution, but the model also simulates evapotranspiration and groundwater recharge during rain-free periods at a longer time step. The model framework was applied to several case studies in Germany where intense rainfall events produced flash floods causing high damage in urban areas and to a long-term research catchment in an urban setting (Vauban, Freiburg), where a variety of green infrastructures dominates the hydrology. Urban-RoGeR allowed us to study the effects of different green infrastructures on reducing the flood peak, but also its effect on the water balance (evapotranspiration and groundwater

GOES-R Fairing Inspection

NASA Image and Video Library

2016-09-26

Team members with United Launch Alliance (ULA) inspect an clean the first half of the fairing for the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

GOES-R Fairing Inspection

NASA Image and Video Library

2016-09-26

Both halves of the fairing for the Geostationary Operational Environmental Satellite (GOES-R) are being inspected and cleaned by United Launch Alliance (ULA) team members inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a ULA Atlas V rocket in November.

Detection of Lock on Radar System Based on Ultrasonic US 100 Sensor And Arduino Uno R3 With Image Processing GUI

NASA Astrophysics Data System (ADS)

Baskoro, F.; Reynaldo, B. R.

2018-04-01

The development of electronics technology especially in the field of microcontroller occurs very rapidly. There have been many applications and useful use of microcontroller in everyday life as well as in laboratory research. In this study used Arduino Uno R3 as microcontroller-based platform ATMega328 as a sensor distance meter to know the distance of an object with high accuracy. The method used is to utilize the function Timer / Counter in Arduino UNO R3. On the Arduino Uno R3 platform, there is ATMEL ATmega328 microcontroller which has a frequency generating speed up to 20 MHz, 16-bit enumeration capability and using C language as its programming. With the Arduino Uno R3 platform, the ATmega328 microcontroller can be programmed with Arduino IDE software that is simpler and easier because it has been supported by libraries and many support programs. The result of this research is distance measurement to know the location of an object using US ultrasonic wave sensor US 100 with Arduino Uno R3 based on ATMega328 microcontroller which then the result will be displayed using Image Processing.

β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N=82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process.

PubMed

Lorusso, G; Nishimura, S; Xu, Z Y; Jungclaus, A; Shimizu, Y; Simpson, G S; Söderström, P-A; Watanabe, H; Browne, F; Doornenbal, P; Gey, G; Jung, H S; Meyer, B; Sumikama, T; Taprogge, J; Vajta, Zs; Wu, J; Baba, H; Benzoni, G; Chae, K Y; Crespi, F C L; Fukuda, N; Gernhäuser, R; Inabe, N; Isobe, T; Kajino, T; Kameda, D; Kim, G D; Kim, Y-K; Kojouharov, I; Kondev, F G; Kubo, T; Kurz, N; Kwon, Y K; Lane, G J; Li, Z; Montaner-Pizá, A; Moschner, K; Naqvi, F; Niikura, M; Nishibata, H; Odahara, A; Orlandi, R; Patel, Z; Podolyák, Zs; Sakurai, H; Schaffner, H; Schury, P; Shibagaki, S; Steiger, K; Suzuki, H; Takeda, H; Wendt, A; Yagi, A; Yoshinaga, K

2015-05-15

The β-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.

Insilico study of the A(2A)R-D (2)R kinetics and interfacial contact surface for heteromerization.

PubMed

Prakash, Amresh; Luthra, Pratibha Mehta

2012-10-01

G-protein-coupled receptors (GPCRs) are cell surface receptors. The dynamic property of receptor-receptor interactions in GPCRs modulates the kinetics of G-protein signaling and stability. In the present work, the structural and dynamic study of A(2A)R-D(2)R interactions was carried to acquire the understanding of the A(2A)R-D(2)R receptor activation and deactivation process, facilitating the design of novel drugs and therapeutic target for Parkinson's disease. The structure-based features (Alpha, Beta, SurfAlpha, and SurfBeta; GapIndex, Leakiness and Gap Volume) and slow mode model (ENM) facilitated the prediction of kinetics (K (off), K (on), and K (d)) of A(2A)R-D(2)R interactions. The results demonstrated the correlation coefficient 0.294 for K (d) and K (on) and the correlation coefficient 0.635 for K (d) and K (off), and indicated stable interfacial contacts in the formation of heterodimer. The coulombic interaction involving the C-terminal tails of the A(2A)R and intracellular loops (ICLs) of D(2)R led to the formation of interfacial contacts between A(2A)R-D(2)R. The properties of structural dynamics, ENM and KFC server-based hot-spot analysis illustrated the stoichiometry of A(2A)R-D(2)R contact interfaces as dimer. The propensity of amino acid residues involved in A(2A)R-D(2)R interaction revealed the presence of positively (R, H and K) and negatively (E and D) charged structural motif of TMs and ICL3 of A(2A)R and D(2)R at interface of dimer contact. Essentially, in silico structural and dynamic study of A(2A)R-D(2)R interactions will provide the basic understanding of the A(2A)R-D(2)R interfacial contact surface for activation and deactivation processes, and could be used as constructive model to recognize the protein-protein interactions in receptor assimilations.

Apoptosis-like programmed cell death induces antisense ribosomal RNA (rRNA) fragmentation and rRNA degradation in Leishmania.

PubMed

Padmanabhan, P K; Samant, M; Cloutier, S; Simard, M J; Papadopoulou, B

2012-12-01

Few natural antisense (as) RNAs have been reported as yet in the unicellular protozoan Leishmania. Here, we describe that Leishmania produces natural asRNAs complementary to all ribosomal RNA (rRNA) species. Interestingly, we show that drug-induced apoptosis-like programmed cell death triggers fragmentation of asRNA complementary to the large subunit gamma (LSU-γ) rRNA, one of the six 28S rRNA processed fragments in Leishmania. Heat and oxidative stress also induce fragmentation of asrRNA, but to a lesser extent. Extensive asrRNA cleavage correlates with rRNA breakdown and translation inhibition. Indeed, overexpression of asLSU-γ rRNA accelerates rRNA degradation upon induction of apoptosis. In addition, we provide mechanistic insight into the regulation of apoptosis-induced asrRNA fragmentation by a 67 kDa ATP-dependent RNA helicase of the DEAD-box subfamily. This helicase binds both sense (s)LSU-γ and asLSU-γ rRNAs, and appears to have a key role in protecting rRNA from degradation by preventing asrRNA cleavage and thus cell death. Remarkably, the asrRNA fragmentation process operates not only in trypanosomatid protozoa but also in mammals. Our findings uncover a novel mechanism of regulation involving asrRNA fragmentation and rRNA breakdown, that is triggered by apoptosis and conditions of reduced translation under stress, and seems to be evolutionary conserved.

Apoptosis-like programmed cell death induces antisense ribosomal RNA (rRNA) fragmentation and rRNA degradation in Leishmania

PubMed Central

Padmanabhan, P K; Samant, M; Cloutier, S; Simard, M J; Papadopoulou, B

2012-01-01

Few natural antisense (as) RNAs have been reported as yet in the unicellular protozoan Leishmania. Here, we describe that Leishmania produces natural asRNAs complementary to all ribosomal RNA (rRNA) species. Interestingly, we show that drug-induced apoptosis-like programmed cell death triggers fragmentation of asRNA complementary to the large subunit gamma (LSU-γ) rRNA, one of the six 28S rRNA processed fragments in Leishmania. Heat and oxidative stress also induce fragmentation of asrRNA, but to a lesser extent. Extensive asrRNA cleavage correlates with rRNA breakdown and translation inhibition. Indeed, overexpression of asLSU-γ rRNA accelerates rRNA degradation upon induction of apoptosis. In addition, we provide mechanistic insight into the regulation of apoptosis-induced asrRNA fragmentation by a 67 kDa ATP-dependent RNA helicase of the DEAD-box subfamily. This helicase binds both sense (s)LSU-γ and asLSU-γ rRNAs, and appears to have a key role in protecting rRNA from degradation by preventing asrRNA cleavage and thus cell death. Remarkably, the asrRNA fragmentation process operates not only in trypanosomatid protozoa but also in mammals. Our findings uncover a novel mechanism of regulation involving asrRNA fragmentation and rRNA breakdown, that is triggered by apoptosis and conditions of reduced translation under stress, and seems to be evolutionary conserved. PMID:22767185

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

The GOES-R spacecraft is secured on its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Final Closure Letter for Administrative Complaint Numbers 03R-07-R9, 10R-07-R9 and 01R-11R9

EPA Pesticide Factsheets

On 6-7-2017, ECRCO issued a closure letter for Admin Complaint Numbers 03r-07-r9, 10r-07-r9 and 01r-11-r9 involving the Maricopa County Air Quality Department regarding alleged complaints that MCAQD violated Title 6 of the Civil Rights Act of 1964.

(R-X-R)4 -Motif Peptides Containing Conformationally Constrained Cyclohexane-Derived Spacers: Effect on Cellular Uptake.

PubMed

Bhosle, Govind S; Fernandes, Moneesha

2017-11-08

Arginine-rich peptides having the (R-X-R) n motif are among the most effective cell-penetrating peptides (CPPs). Herein we report a several-fold increase in the efficacy of such CPPs if the linear flexible spacer (-X-) in the (R-X-R) motif is replaced by constrained cyclic 1,4-substituted-cyclohexane-derived spacers. Internalization of these oligomers in mammalian cell lines was found to be an energy-dependent process. Incorporation of these constrained, non-proteinogenic amino acid spacers in the CPPs is shown to enhance their proteolytic stability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

76 FR 72869 - Proposed Establishment of Restricted Areas R-5402, R-5403A, R-5403B, R-5403C, R-5403D, R-5403E...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

...-0117; Airspace Docket No. 09-AGL-31] Proposed Establishment of Restricted Areas R-5402, R-5403A, R- 5403B, R-5403C, R-5403D, R-5403E, and R-5403F; Devils Lake, ND AGENCY: Federal Aviation Administration... Camp Grafton Range, the existing R-5401 restricted area surrounding the range is inadequate to satisfy...

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

An overhead crane lifts the GOES-R spacecraft to move it into its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

An overhead crane is positioned to move the GOES-R spacecraft into its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

An overhead crane moves the GOES-R spacecraft toward its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Identification of Four Oxidative Stress-Responsive MicroRNAs, miR-34a-5p, miR-1915-3p, miR-638, and miR-150-3p, in Hepatocellular Carcinoma.

PubMed

Wan, Yong; Cui, Ruixia; Gu, Jingxian; Zhang, Xing; Xiang, Xiaohong; Liu, Chang; Qu, Kai; Lin, Ting

2017-01-01

Increasing evidence suggests that oxidative stress plays an essential role during carcinogenesis. However, the underlying mechanism between oxidative stress and carcinogenesis remains unknown. Recently, microRNAs (miRNAs) are revealed to be involved in oxidative stress response and carcinogenesis. This study aims to identify miRNAs in hepatocellular carcinoma (HCC) cells which might involve in oxidative stress response. An integrated analysis of miRNA expression signature was performed by employing robust rank aggregation (RRA) method, and four miRNAs (miR-34a-5p, miR-1915-3p, miR-638, and miR-150-3p) were identified as the oxidative stress-responsive miRNAs. Pathway enrichment analysis suggested that these four miRNAs played an important role in antiapoptosis process. Our data also revealed miR-34a-5p and miR-1915-3p, but not miR-150-3p and miR-638, were regulated by p53 in HCC cell lines under oxidative stress. In addition, clinical investigation revealed that these four miRNAs might be involved in oxidative stress response by targeting oxidative stress-related genes in HCC tissues. Kaplan-Meier analysis showed that these four miRNAs were associated with patients' overall survival. In conclusion, we identified four oxidative stress-responsive miRNAs, which were regulated by p53-dependent (miR-34a-5p and miR-1915-3p) and p53-independent pathway (miR-150-3p and miR-638). These four miRNAs may offer new strategy for HCC diagnosis and prognosis.

Muenke Syndrome Mutation, FgfR3P244R, Causes TMJ Defects

PubMed Central

Yasuda, T.; Nah, H.D.; Laurita, J.; Kinumatsu, T.; Shibukawa, Y.; Shibutani, T.; Minugh-Purvis, N.; Pacifici, M.; Koyama, E.

2012-01-01

Muenke syndrome is characterized by various craniofacial deformities and is caused by an autosomal-dominant activating mutation in fibroblast growth factor receptor 3 (FGFR3P250R). Here, using mice carrying a corresponding mutation (FgfR3P244R), we determined whether the mutation affects temporomandibular joint (TMJ) development and growth. In situ hybridization showed that FgfR3 was expressed in condylar chondroprogenitors and maturing chondrocytes that also expressed the Indian hedgehog (Ihh) receptor and transcriptional target Patched 1(Ptch1). In FgfR3P244R mutants, the condyles displayed reduced levels of Ihh expression, H4C-positive proliferating chondroprogenitors, and collagen type II- and type X-expressing chondrocytes. Primary bone spongiosa formation was also disturbed and was accompanied by increased osteoclastic activity and reduced trabecular bone formation. Treatment of wild-type condylar explants with recombinant FGF2/FGF9 decreased Ptch1 and PTHrP expression in superficial/polymorphic layers and proliferation in chondroprogenitors. We also observed early degenerative changes of condylar articular cartilage, abnormal development of the articular eminence/glenoid fossa in the TMJ, and fusion of the articular disc. Analysis of our data indicates that the activating FgfR3P244R mutation disturbs TMJ developmental processes, likely by reducing hedgehog signaling and endochondral ossification. We suggest that a balance between FGF and hedgehog signaling pathways is critical for the integrity of TMJ development and for the maintenance of cellular organization. PMID:22622662

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

The Geostationary Operational Environmental Satellite (GOES-R) is lifted to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

The Geostationary Operational Environmental Satellite (GOES-R) is raised to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

Team members monitor progress as an overhead crane lowers the GOES-R spacecraft into its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Lift to Stand

NASA Image and Video Library

2016-08-23

Team members monitor progress as an overhead crane lowers the GOES-R spacecraft toward its work stand inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

The Geostationary Operational Environmental Satellite (GOES-R) has been secured in the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members are securing the Geostationary Operational Environmental Satellite (GOES-R) in the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

[Emotional processing in patients with a dissocial personality disorder subtype "psychopathy" according to PCL-R].

PubMed

Weber, Tatjana; Sommer, Monika; Hajak, Göran; Müller, Jürgen

2004-11-01

Functional MRI was used to test the effects of the deficient emotional responsiveness of psychopathic patients on cognitive processes. We used a Simon-paradigm, in which ten healthy volunteers and ten patients with a diagnosis of "psychopathy" (defined by Hare Psychopathy Checklist Revised) have to select their spatially defined responses on the basis of a nonspatial stimuli feature. For the emotion induction pictures from the International Affective Picture System (IAPS) were selected. At the beginning and intermediated by the Simon-paradigm blocks of positive, negative or neutral pictures were presented. Patients with "psychopathy" exhibited untypical activation patterns in amygdala and prefrontal regions during interferences between negative or positive stimulations and cognitive tasks. These results demonstrated disturbed regulation of emotion-cognition-interaction in "psychopathy" according to PCL-R.

Jet activity in the symbiotic variable R Aquarii

NASA Technical Reports Server (NTRS)

Michalitsianos, A. G.; Hollis, J. M.; Kafatos, M.

1986-01-01

Low-resolution ultraviolet spectra of the R Aquarii jet have been obtained with the International Ultraviolet Explorer (IUE). The most recent IUE observations indicate the ionization state of the jet is increasing. Subarcsecond, Very Large Array observations of R Aquarii have resolved the radio-continuum structure into discrete parcels of emission that are extended and nearly collinear. R Aquarii provides evidence that indicates stellar jet activity is not unique to objects associated with high-energy emission processes alone. Rather, the nature of the aligned radio-optical features that comprise the R Aquarii jet indicate that directional mass expulsion, in the form of discrete-collimated ejecta, probably reflect a general, underlying, physical process associated with a wide variety of peculiar stellar objects. As such, the R Aquarii jet constitutes a prototype for jet activity in composite or peculiar emission stars.

Knowledge Integration in Global R&D Networks

NASA Astrophysics Data System (ADS)

Erkelens, Rose; van den Hooff, Bart; Vlaar, Paul; Huysman, Marleen

This paper reports a qualitative study conducted at multinational organizations' R&D departments about their process of knowledge integration. Taking into account the knowledge based view (KBV) of the firm and the practice-based view of knowledge, and building on the literatures concerning specialization and integration of knowledge in organizations, we explore which factors may have a significant influence on the integration process of knowledge between R&D units. The findings indicated (1) the contribution of relevant factors influencing knowledge integration processes and (2) a thoughtful balance between engineering and emergent approaches to be helpful in understanding and overcoming knowledge integration issues.

PAL[R] Services Being Measured through Scientifically-Based Evaluation Process

ERIC Educational Resources Information Center

Perspectives in Peer Programs, 2007

2007-01-01

In January 2006, PAL[R] Peer Assistance and Leadership, a Promising Prevention Program of Workers Assistance Program, Inc. (WAP), received a $30,000 grant from the Center for Substance Abuse Prevention (CSAP) in order to be scientifically-evaluated on the outcomes and effectiveness of its programs and services. According to the grant, the…

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members assist as the Geostationary Operational Environmental Satellite (GOES-R) is prepared for lifting to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members monitor the progress as the Geostationary Operational Environmental Satellite (GOES-R) is lifted to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members check the Geostationary Operational Environmental Satellite (GOES-R) after it was lifted to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

R software package based statistical optimization of process components to simultaneously enhance the bacterial growth, laccase production and textile dye decolorization with cytotoxicity study

PubMed Central

Dudhagara, Pravin; Tank, Shantilal

2018-01-01

The thermophilic bacterium, Bacillus licheniformis U1 is used for the optimization of bacterial growth (R1), laccase production (R2) and synthetic disperse blue DBR textile dye decolorization (R3) in the present study. Preliminary optimization has been performed by one variable at time (OVAT) approach using four media components viz., dye concentration, copper sulphate concentration, pH, and inoculum size. Based on OVAT result further statistical optimization of R1, R2 and R3 performed by Box–Behnken design (BBD) using response surface methodology (RSM) in R software with R Commander package. The total 29 experimental runs conducted in the experimental design study towards the construction of a quadratic model. The model indicated that dye concentration 110 ppm, copper sulphate 0.2 mM, pH 7.5 and inoculum size 6% v/v were found to be optimum to maximize the laccase production and bacterial growth. Whereas, maximum dye decolorization achieved in media containing dye concentration 110 ppm, copper sulphate 0.6 mM, pH 6 and inoculum size 6% v/v. R package predicted R2 of R1, R2 and R3 were 0.9917, 0.9831 and 0.9703 respectively; likened to Design-Expert (Stat-Ease) (DOE) predicted R2 of R1, R2, and R3 were 0.9893, 0.9822 and 0.8442 respectively. The values obtained by R software were more precise, reliable and reproducible, compared to the DOE model. The laccase production was 1.80 fold increased, and 2.24 fold enhancement in dye decolorization was achieved using optimized medium than initial experiments. Moreover, the laccase-treated sample demonstrated the less cytotoxic effect on L132 and MCF-7 cell lines compared to untreated sample using MTT assay. Higher cell viability and lower cytotoxicity observed in a laccase-treated sample suggest the impending application of bacterial laccase in the reduction of toxicity of dye to design rapid biodegradation process. PMID:29718934

Statistical Signal Process in R Language in the Pharmacovigilance Programme of India.

PubMed

Kumar, Aman; Ahuja, Jitin; Shrivastava, Tarani Prakash; Kumar, Vipin; Kalaiselvan, Vivekanandan

2018-05-01

The Ministry of Health & Family Welfare, Government of India, initiated the Pharmacovigilance Programme of India (PvPI) in July 2010. The purpose of the PvPI is to collect data on adverse reactions due to medications, analyze it, and use the reference to recommend informed regulatory intervention, besides communicating the risk to health care professionals and the public. The goal of the present study was to apply statistical tools to find the relationship between drugs and ADRs for signal detection by R programming. Four statistical parameters were proposed for quantitative signal detection. These 4 parameters are IC 025 , PRR and PRR lb , chi-square, and N 11 ; we calculated these 4 values using R programming. We analyzed 78,983 drug-ADR combinations, and the total count of drug-ADR combination was 4,20,060. During the calculation of the statistical parameter, we use 3 variables: (1) N 11 (number of counts), (2) N 1. (Drug margin), and (3) N .1 (ADR margin). The structure and calculation of these 4 statistical parameters in R language are easily understandable. On the basis of the IC value (IC value >0), out of the 78,983 drug-ADR combination (drug-ADR combination), we found the 8,667 combinations to be significantly associated. The calculation of statistical parameters in R language is time saving and allows to easily identify new signals in the Indian ICSR (Individual Case Safety Reports) database.

Assessment of error rates in acoustic monitoring with the R package monitoR

USGS Publications Warehouse

Katz, Jonathan; Hafner, Sasha D.; Donovan, Therese

2016-01-01

Detecting population-scale reactions to climate change and land-use change may require monitoring many sites for many years, a process that is suited for an automated system. We developed and tested monitoR, an R package for long-term, multi-taxa acoustic monitoring programs. We tested monitoR with two northeastern songbird species: black-throated green warbler (Setophaga virens) and ovenbird (Seiurus aurocapilla). We compared detection results from monitoR in 52 10-minute surveys recorded at 10 sites in Vermont and New York, USA to a subset of songs identified by a human that were of a single song type and had visually identifiable spectrograms (e.g. a signal:noise ratio of at least 10 dB: 166 out of 439 total songs for black-throated green warbler, 502 out of 990 total songs for ovenbird). monitoR’s automated detection process uses a ‘score cutoff’, which is the minimum match needed for an unknown event to be considered a detection and results in a true positive, true negative, false positive or false negative detection. At the chosen score cut-offs, monitoR correctly identified presence for black-throated green warbler and ovenbird in 64% and 72% of the 52 surveys using binary point matching, respectively, and 73% and 72% of the 52 surveys using spectrogram cross-correlation, respectively. Of individual songs, 72% of black-throated green warbler songs and 62% of ovenbird songs were identified by binary point matching. Spectrogram cross-correlation identified 83% of black-throated green warbler songs and 66% of ovenbird songs. False positive rates were  for song event detection.

Decreased miR-128 and increased miR-21 synergistically cause podocyte injury in sepsis.

PubMed

Wang, Shanshan; Wang, Jun; Zhang, Zengdi; Miao, Hongjun

2017-08-01

Glomerular podocytes are injured in sepsis. We studied, in a sepsis patient, whether microRNAs (miRNAs) play a role in the podocyte injury. Podocytes were cultured and treated with lipopolysaccharide (LPS). Filtration barrier function of podocyte was analyzed with albumin influx assay. Nephrin level was analyzed with reverse transcription polymerase chain reaction (RT-PCR) and western blot. MiRNAs were detected using miRNAs PCR Array and in situ hybridization. MiRNA target sites were evaluated with luciferase reporter assays. LPS impaired the filtration barrier function of podocytes. MiR-128 level was decreased and miR-21 level was increased in podocytes in vitro and in the sepsis patient. The decrease in miR-128 was sufficient to induce the loss of nephrin and the impairment of filtration barrier function, while the increase of miR-21 exacerbated the process. Snail and phosphatase and tensin homolog (PTEN) were identified as the targets of miR-128 and miR-21. Decreased miR-128 induced Snail expression, and the increased miR-21 stabilized Snail by regulating the PTEN/Akt/GSK3β pathway. Supplementation of miR-128 and inhibition of miR-21 suppressed Snail expression and prevented the podocyte injury induced by LPS. Our study suggests that decreased miR-128 and increased miR-21 synergistically cause podocyte injury and are the potential therapeutic targets in sepsis.

Parallel processing of real-time dynamic systems simulation on OSCAR (Optimally SCheduled Advanced multiprocessoR)

NASA Technical Reports Server (NTRS)

Kasahara, Hironori; Honda, Hiroki; Narita, Seinosuke

1989-01-01

Parallel processing of real-time dynamic systems simulation on a multiprocessor system named OSCAR is presented. In the simulation of dynamic systems, generally, the same calculation are repeated every time step. However, we cannot apply to Do-all or the Do-across techniques for parallel processing of the simulation since there exist data dependencies from the end of an iteration to the beginning of the next iteration and furthermore data-input and data-output are required every sampling time period. Therefore, parallelism inside the calculation required for a single time step, or a large basic block which consists of arithmetic assignment statements, must be used. In the proposed method, near fine grain tasks, each of which consists of one or more floating point operations, are generated to extract the parallelism from the calculation and assigned to processors by using optimal static scheduling at compile time in order to reduce large run time overhead caused by the use of near fine grain tasks. The practicality of the scheme is demonstrated on OSCAR (Optimally SCheduled Advanced multiprocessoR) which has been developed to extract advantageous features of static scheduling algorithms to the maximum extent.

Interpolating of climate data using R

NASA Astrophysics Data System (ADS)

Reinhardt, Katja

2017-04-01

Interpolation methods are used in many different geoscientific areas, such as soil physics, climatology and meteorology. Thereby, unknown values are calculated by using statistical calculation approaches applied on known values. So far, the majority of climatologists have been using computer languages, such as FORTRAN or C++, but there is also an increasing number of climate scientists using R for data processing and visualization. Most of them, however, are still working with arrays and vector based data which is often associated with complex R code structures. For the presented study, I have decided to convert the climate data into geodata and to perform the whole data processing using the raster package, gstat and similar packages, providing a much more comfortable way for data handling. A central goal of my approach is to create an easy to use, powerful and fast R script, implementing the entire geodata processing and visualization into a single and fully automated R based procedure, which allows avoiding the necessity of using other software packages, such as ArcGIS or QGIS. Thus, large amount of data with recurrent process sequences can be processed. The aim of the presented study, which is located in western Central Asia, is to interpolate wind data based on the European reanalysis data Era-Interim, which are available as raster data with a resolution of 0.75˚ x 0.75˚ , to a finer grid. Therefore, various interpolation methods are used: inverse distance weighting, the geostatistical methods ordinary kriging and regression kriging, generalized additve model and the machine learning algorithms support vector machine and neural networks. Besides the first two mentioned methods, the methods are used with influencing factors, e.g. geopotential and topography.

Elevated levels of Era GTPase improve growth, 16S rRNA processing, and 70S ribosome assembly of Escherichia coli lacking highly conserved multifunctional YbeY endoribonuclease.

PubMed

Ghosal, Anubrata; Babu, Vignesh M P; Walker, Graham C

2018-06-18

YbeY is a highly conserved, multifunctional endoribonuclease that plays a significant role in ribosome biogenesis and has several additional roles. Here, we show in Escherichia coli that overexpressing the conserved GTPase, Era, partially suppresses the growth defect of a ΔybeY strain while improving 16S rRNA processing and 70S ribosome assembly. This suppression requires both Era's ability to hydrolyze GTP and the function of three exoribonucleases, RNase II, RNase R and RNase PH, suggesting a model for Era's action. Overexpressing Vibrio cholerae Era similarly partially suppresses the defects of an E. coli ΔybeY strain indicating this property of Era is conserved in bacteria other than E. coli Importance This work provides additional insights into the critical, but still incompletely understood, mechanism of the processing of the E. coli 16S rRNA 3'-terminus. The highly conserved GTPase, Era, is known to bind to the precursor of the 16S rRNA near its 3-end. Both the endoribonuclease YbeY, which binds to Era, and four exoribonucleases have been implicated in this 3'-end processing. Results reported here offer additional insights into the role of Era in 16S rRNA 3'-maturation and into the relationship between the action of the endoribonuclease YbeY and the four exoribonucleases. This study also hints at why YbeY is only essential in some bacteria and suggests that the YbeY could be a target for a new class of antibiotic in these bacteria. Copyright © 2018 American Society for Microbiology.

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members assist as the Geostationary Operational Environmental Satellite (GOES-R) is raised and prepared for lifting to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November

GOES-R Rotation to Vertical

NASA Image and Video Library

2016-09-15

Team members assist as the Geostationary Operational Environmental Satellite (GOES-R) is raised and prepared for lifting to the vertical position on an “up-ender” inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Optimizing R with SparkR on a commodity cluster for biomedical research.

PubMed

Sedlmayr, Martin; Würfl, Tobias; Maier, Christian; Häberle, Lothar; Fasching, Peter; Prokosch, Hans-Ulrich; Christoph, Jan

2016-12-01

Medical researchers are challenged today by the enormous amount of data collected in healthcare. Analysis methods such as genome-wide association studies (GWAS) are often computationally intensive and thus require enormous resources to be performed in a reasonable amount of time. While dedicated clusters and public clouds may deliver the desired performance, their use requires upfront financial efforts or anonymous data, which is often not possible for preliminary or occasional tasks. We explored the possibilities to build a private, flexible cluster for processing scripts in R based on commodity, non-dedicated hardware of our department. For this, a GWAS-calculation in R on a single desktop computer, a Message Passing Interface (MPI)-cluster, and a SparkR-cluster were compared with regards to the performance, scalability, quality, and simplicity. The original script had a projected runtime of three years on a single desktop computer. Optimizing the script in R already yielded a significant reduction in computing time (2 weeks). By using R-MPI and SparkR, we were able to parallelize the computation and reduce the time to less than three hours (2.6 h) on already available, standard office computers. While MPI is a proven approach in high-performance clusters, it requires rather static, dedicated nodes. SparkR and its Hadoop siblings allow for a dynamic, elastic environment with automated failure handling. SparkR also scales better with the number of nodes in the cluster than MPI due to optimized data communication. R is a popular environment for clinical data analysis. The new SparkR solution offers elastic resources and allows supporting big data analysis using R even on non-dedicated resources with minimal change to the original code. To unleash the full potential, additional efforts should be invested to customize and improve the algorithms, especially with regards to data distribution. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All

Antiausterity activity of arctigenin enantiomers: importance of (2R,3R)-absolute configuration.

PubMed

Awale, Suresh; Kato, Mamoru; Dibwe, Dya Fita; Li, Feng; Miyoshi, Chika; Esumi, Hiroyasu; Kadota, Shigetoshi; Tezuka, Yasuhiro

2014-01-01

From a MeOH extract of powdered roots of Wikstroemia indica, six dibenzyl-gamma-butyrolactone-type lignans with (2S,3S)-absolute configuration [(+)-arctigenin (1), (+)-matairesinol (2), (+)-trachelogenin (3), (+)-nortrachelogenin (4), (+)-hinokinin (5), and (+)-kusunokinin (6)] were isolated, whereas three dibenzyl-gamma-butyrolactone-type lignans with (2R,3R)-absolute configuration [(-)-arctigenin (1*), (-)-matairesinol (2*), (-)-trachelogenin (3*)] were isolated from Trachelospermum asiaticum. The in vitro preferential cytotoxic activity of the nine compounds was evaluated against human pancreatic PANC-1 cancer cells in nutrient-deprived medium (NDM), but none of the six lignans (1-6) with (2S,3S)-absolute configuration showed preferential cytotoxicity. On the other hand, three lignans (1*-3*) with (2R,3R)-absolute configuration exhibited preferential cytotoxicity in a concentration-dependent manner with PC50 values of 0.54, 6.82, and 5.85 microM, respectively. Furthermore, the effect of (-)- and (+)-arctigenin was evaluated against the activation of Akt, which is a key process in the tolerance to nutrition starvation. Interestingly, only (-)-arctigenin (1*) strongly suppressed the activation of Akt. These results indicate that the (2R,3R)-absolute configuration of (-)-enantiomers should be required for the preferential cytotoxicity through the inhibition of Akt activation.

Design and implementation of adaptive PI control schemes for web tension control in roll-to-roll (R2R) manufacturing.

PubMed

Raul, Pramod R; Pagilla, Prabhakar R

2015-05-01

In this paper, two adaptive Proportional-Integral (PI) control schemes are designed and discussed for control of web tension in Roll-to-Roll (R2R) manufacturing systems. R2R systems are used to transport continuous materials (called webs) on rollers from the unwind roll to the rewind roll. Maintaining web tension at the desired value is critical to many R2R processes such as printing, coating, lamination, etc. Existing fixed gain PI tension control schemes currently used in industrial practice require extensive tuning and do not provide the desired performance for changing operating conditions and material properties. The first adaptive PI scheme utilizes the model reference approach where the controller gains are estimated based on matching of the actual closed-loop tension control systems with an appropriately chosen reference model. The second adaptive PI scheme utilizes the indirect adaptive control approach together with relay feedback technique to automatically initialize the adaptive PI gains. These adaptive tension control schemes can be implemented on any R2R manufacturing system. The key features of the two adaptive schemes is that their designs are simple for practicing engineers, easy to implement in real-time, and automate the tuning process. Extensive experiments are conducted on a large experimental R2R machine which mimics many features of an industrial R2R machine. These experiments include trials with two different polymer webs and a variety of operating conditions. Implementation guidelines are provided for both adaptive schemes. Experimental results comparing the two adaptive schemes and a fixed gain PI tension control scheme used in industrial practice are provided and discussed. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Rosen's (M,R) system in Unified Modelling Language.

PubMed

Zhang, Ling; Williams, Richard A; Gatherer, Derek

2016-01-01

Robert Rosen's (M,R) system is an abstract biological network architecture that is allegedly non-computable on a Turing machine. If (M,R) is truly non-computable, there are serious implications for the modelling of large biological networks in computer software. A body of work has now accumulated addressing Rosen's claim concerning (M,R) by attempting to instantiate it in various software systems. However, a conclusive refutation has remained elusive, principally since none of the attempts to date have unambiguously avoided the critique that they have altered the properties of (M,R) in the coding process, producing merely approximate simulations of (M,R) rather than true computational models. In this paper, we use the Unified Modelling Language (UML), a diagrammatic notation standard, to express (M,R) as a system of objects having attributes, functions and relations. We believe that this instantiates (M,R) in such a way than none of the original properties of the system are corrupted in the process. Crucially, we demonstrate that (M,R) as classically represented in the relational biology literature is implicitly a UML communication diagram. Furthermore, since UML is formally compatible with object-oriented computing languages, instantiation of (M,R) in UML strongly implies its computability in object-oriented coding languages. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Diagnostic and prognostic potential of serum miR-7, miR-16, miR-25, miR-93, miR-182, miR-376a and miR-429 in ovarian cancer patients.

PubMed

Meng, Xiaodan; Joosse, Simon A; Müller, Volkmar; Trillsch, Fabian; Milde-Langosch, Karin; Mahner, Sven; Geffken, Maria; Pantel, Klaus; Schwarzenbach, Heidi

2015-11-03

Owing to late diagnosis in advanced disease stages, prognosis of patients with epithelial ovarian cancer (EOC) is poor. The quantification of deregulated levels of microRNAs could facilitate earlier diagnosis and improve prognosis of EOC. Seven microRNAs (miR-7, miR-16, miR-25, miR-93, miR-182, miR-376a and miR-429) were quantified in the serum of 180 EOC patients and 66 healthy women by TaqMan PCR microRNA assays. Median follow-up time was 21 months. The effects of miR-7 and miR-429 on apoptosis, cell proliferation, migration and invasion were investigated in two (EOC) cell lines. Serum levels of miR-25 (P=0.0001) and miR-93 (P=0.0001) were downregulated, whereas those of miR-7 (P=0.001) and miR-429 (P=0.0001) were upregulated in EOC patients compared with healthy women. The four microRNAs discriminated EOC patients from healthy women with a sensitivity of 93% and a specificity of 92%. The levels of miR-429 positively correlated with CA125 values (P=0.0001) and differed between FIGO I-II and III-IV stages (P=0.001). MiR-429 was an independent predictor of overall survival (P=0.011). Overexpressed miR-429 in SKOV3 cells led to suppression of cell migration (P=0.037) and invasion (P=0.011). Increased levels of miR-7 were associated with lymph node metastases (P=0.0001) and FIGO stages III-IV (P=0.0001). Overexpressed miR-7 in SKOV3 cells resulted in increased cell migration (P=0.001) and invasion (P=0.011). Additionally, the increased levels of miR-376a correlated with FIGO stages III-IV (P=0.02). Our data indicate the diagnostic potential of miR-7, miR-25, miR-93 and miR-429 in EOC and the prognostic potential of miR-429. This microRNA panel may be promising molecules to be targeted in the treatment of EOC.

Optimized R functions for analysis of ecological community data using the R virtual laboratory (RvLab)

PubMed Central

Varsos, Constantinos; Patkos, Theodore; Pavloudi, Christina; Gougousis, Alexandros; Ijaz, Umer Zeeshan; Filiopoulou, Irene; Pattakos, Nikolaos; Vanden Berghe, Edward; Fernández-Guerra, Antonio; Faulwetter, Sarah; Chatzinikolaou, Eva; Pafilis, Evangelos; Bekiari, Chryssoula; Doerr, Martin; Arvanitidis, Christos

2016-01-01

Abstract Background Parallel data manipulation using R has previously been addressed by members of the R community, however most of these studies produce ad hoc solutions that are not readily available to the average R user. Our targeted users, ranging from the expert ecologist/microbiologists to computational biologists, often experience difficulties in finding optimal ways to exploit the full capacity of their computational resources. In addition, improving performance of commonly used R scripts becomes increasingly difficult especially with large datasets. Furthermore, the implementations described here can be of significant interest to expert bioinformaticians or R developers. Therefore, our goals can be summarized as: (i) description of a complete methodology for the analysis of large datasets by combining capabilities of diverse R packages, (ii) presentation of their application through a virtual R laboratory (RvLab) that makes execution of complex functions and visualization of results easy and readily available to the end-user. New information In this paper, the novelty stems from implementations of parallel methodologies which rely on the processing of data on different levels of abstraction and the availability of these processes through an integrated portal. Parallel implementation R packages, such as the pbdMPI (Programming with Big Data – Interface to MPI) package, are used to implement Single Program Multiple Data (SPMD) parallelization on primitive mathematical operations, allowing for interplay with functions of the vegan package. The dplyr and RPostgreSQL R packages are further integrated offering connections to dataframe like objects (databases) as secondary storage solutions whenever memory demands exceed available RAM resources. The RvLab is running on a PC cluster, using version 3.1.2 (2014-10-31) on a x86_64-pc-linux-gnu (64-bit) platform, and offers an intuitive virtual environmet interface enabling users to perform analysis of ecological

Optimized R functions for analysis of ecological community data using the R virtual laboratory (RvLab).

PubMed

Varsos, Constantinos; Patkos, Theodore; Oulas, Anastasis; Pavloudi, Christina; Gougousis, Alexandros; Ijaz, Umer Zeeshan; Filiopoulou, Irene; Pattakos, Nikolaos; Vanden Berghe, Edward; Fernández-Guerra, Antonio; Faulwetter, Sarah; Chatzinikolaou, Eva; Pafilis, Evangelos; Bekiari, Chryssoula; Doerr, Martin; Arvanitidis, Christos

2016-01-01

Parallel data manipulation using R has previously been addressed by members of the R community, however most of these studies produce ad hoc solutions that are not readily available to the average R user. Our targeted users, ranging from the expert ecologist/microbiologists to computational biologists, often experience difficulties in finding optimal ways to exploit the full capacity of their computational resources. In addition, improving performance of commonly used R scripts becomes increasingly difficult especially with large datasets. Furthermore, the implementations described here can be of significant interest to expert bioinformaticians or R developers. Therefore, our goals can be summarized as: (i) description of a complete methodology for the analysis of large datasets by combining capabilities of diverse R packages, (ii) presentation of their application through a virtual R laboratory (RvLab) that makes execution of complex functions and visualization of results easy and readily available to the end-user. In this paper, the novelty stems from implementations of parallel methodologies which rely on the processing of data on different levels of abstraction and the availability of these processes through an integrated portal. Parallel implementation R packages, such as the pbdMPI (Programming with Big Data - Interface to MPI) package, are used to implement Single Program Multiple Data (SPMD) parallelization on primitive mathematical operations, allowing for interplay with functions of the vegan package. The dplyr and RPostgreSQL R packages are further integrated offering connections to dataframe like objects (databases) as secondary storage solutions whenever memory demands exceed available RAM resources. The RvLab is running on a PC cluster, using version 3.1.2 (2014-10-31) on a x86_64-pc-linux-gnu (64-bit) platform, and offers an intuitive virtual environmet interface enabling users to perform analysis of ecological and microbial communities based on

Unconscious Priming According to Multiple S-R Rules

ERIC Educational Resources Information Center

Kiesel, Andrea; Kunde, Wilfried; Hoffmann, Joachim

2007-01-01

The present study investigated if unconscious primes can be processed according to different stimulus-response (S-R) rules simultaneously. Participants performed two different S-R rules, such as judging a digit as smaller or larger than five and judging a letter as vowel or consonant. These S-R rules were administered in random order and announced…

Novel Triazole linked 2-phenyl benzoxazole derivatives induce apoptosis by inhibiting miR-2, miR-13 and miR-14 function in Drosophila melanogaster.

PubMed

Mondal, Tanmoy; Lavanya, A V S; Mallick, Akash; Dadmala, Tulshiram L; Kumbhare, Ravindra M; Bhadra, Utpal; Bhadra, Manika Pal

2017-06-01

Apoptosis is an important phenomenon in multi cellular organisms for maintaining tissue homeostasis and embryonic development. Defect in apoptosis leads to a number of disorders like- autoimmune disorder, immunodeficiency and cancer. 21-22 nucleotides containing micro RNAs (miRNAs/miRs) function as a crucial regulator of apoptosis alike other cellular pathways. Recently, small molecules have been identified as a potent inducer of apoptosis. In this study, we have identified novel Triazole linked 2-phenyl benzoxazole derivatives (13j and 13h) as a negative regulator of apoptosis inhibiting micro RNAs (miR-2, miR-13 and miR-14) in a well established in vivo model Drosophila melanogaster where the process of apoptosis is very similar to human apoptosis. These compounds inhibit miR-2, miR-13 and miR-14 activity at their target sites, which induce an increased caspase activity, and in turn influence the caspase dependent apoptotic pathway. These two compounds also increase the mitochondrial reactive oxygen species (ROS) level to trigger apoptotic cell death.

Dexterity with numbers: rTMS over left angular gyrus disrupts finger gnosis and number processing.

PubMed

Rusconi, Elena; Walsh, Vincent; Butterworth, Brian

2005-01-01

Since the original description of Gerstmann's syndrome with its four cardinal symptoms, among which are finger agnosia and acalculia, the neuro-cognitive relationship between fingers and calculation has been debated. We asked our participants to perform four different tasks, two of which involved fingers and the other two involving numbers, during repetitive transcranial magnetic stimulation (rTMS) over the posterior parietal lobe of either hemisphere. In the finger tasks, they were required to transform a tactile stimulus randomly delivered on one of their fingers into a speeded key-press response either with the same or with the homologous finger on the opposite hand. In the numerical tasks, they were asked to perform a magnitude or a parity matching on pairs of single digits, in the context of arithmetically related or unrelated numerical primes. In accordance with the original anatomical hypothesis put forward by Gerstmann [Gerstmann, J. (1924). Fingeragnosie: eine umschriebene Stoerung der Orienterung am eigenen Koerper. Wiener clinische Wochenschrift, 37, 1010-12], we found that rTMS over the left angular gyrus disrupted tasks requiring access to the finger schema and number magnitude processing in the same group of participants. In addition to the numerous studies which have employed special populations such as neurological patients and children, our data confirm the presence of a relationship between numbers and body knowledge in skilled adults who no longer use their fingers for solving simple arithmetical tasks.

DEMONSTRATION BULLETIN: EX-SITU ANAEROBIC BIOREMEDIATION TECHNOLOGY - TNT - J.R. SIMPLOT COMPANY

EPA Science Inventory

The J. R. Simplot Ex-Situ Anaerobic Bioremediation System, also known as the J.R. Simplot Anaerobic Biological Remediaton Process (the SABRE™ Process), is a technology designed to destroy nitroaromatic and energetic compounds. The process does not evolve any known toxic intermedi...

Clinorotation influences rDNA and NopA100 localization in nucleoli

NASA Astrophysics Data System (ADS)

Sobol, M. A.; González-Camacho, F.; Rodríguez-Vilariño, V.; Kordyum, E. L.; Medina, F. J.

The nucleolus is the transcription site of rRNA genes as well as the site of processing and initial packaging of their transcripts. The plant nucleolin homologue NopA100 is involved in the regulation of r-chromatin condensation/expansion and rDNA transcription as well as in rRNA processing. We have investigated with immunogold electron microscopy the location of nucleolar DNA and NopA100 in cress root meristematic cells grown under slow horizontal clinorotation, reproducing an important feature of microgravity, namely the absence of an orienting action of a gravity vector, compared to control conditions. We demonstrate redistribution of both rDNA and NopA100 in nucleolar subcomponents induced by clinorotation. Ribosomal DNA concentrated predominantly in fibrillar centers in the form of condensed r-chromatin inclusions and internal non condensed fibrils, redistributing from the dense fibrillar component and the transition zone between fibrillar centers and the dense fibrillar component, recognized as the loci of rDNA transcription. The content of NopA100 was much higher in the inner space of fibrillar centers and reduced in the dense fibrillar component as compared to the control. Based on these data, an effect of slow horizontal clinorotation in lowering the level of rDNA transcription as well as rRNA processing is suggested.

Crowdsourced 'R&D' and medical research.

PubMed

Callaghan, Christian William

2015-09-01

Crowdsourced R&D, a research methodology increasingly applied to medical research, has properties well suited to large-scale medical data collection and analysis, as well as enabling rapid research responses to crises such as disease outbreaks. Multidisciplinary literature offers diverse perspectives of crowdsourced R&D as a useful large-scale medical data collection and research problem-solving methodology. Crowdsourced R&D has demonstrated 'proof of concept' in a host of different biomedical research applications. A wide range of quality and ethical issues relate to crowdsourced R&D. The rapid growth in applications of crowdsourced R&D in medical research is predicted by an increasing body of multidisciplinary theory. Further research in areas such as artificial intelligence may allow better coordination and management of the high volumes of medical data and problem-solving inputs generated by the crowdsourced R&D process. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Lipid raft-mediated miR-3908 inhibition of migration of breast cancer cell line MCF-7 by regulating the interactions between AdipoR1 and Flotillin-1.

PubMed

Li, Yuan; Shan, Fei; Chen, Jinglong

2017-03-21

The mechanisms of lipid raft regulation by microRNAs in breast cancer are not fully understood. This work focused on the evaluation and identification of miR-3908, which may be a potential biomarker related to the migration of breast cancer cells, and elucidates lipid-raft-regulating cell migration in breast cancer. To confirm the prediction that miR-3908 is matched with AdipoR1, we used 3'-UTR luciferase activity of AdipoR1 to assess this. Then, human breast cancer cell line MCF-7 was cultured in the absence or presence of the mimics or inhibitors of miR-3908, after which the biological functions of MCF-7 cells were analyzed. The protein expression of AdipoR1, AMPK, and SIRT-1 were examined. The interaction between AdipoR1 and Flotillin-1, or its effects on lipid rafts on regulating cell migration of MCF-7, was also investigated. AdipoR1 is a direct target of miR-3908. miR-3908 suppresses the expression of AdipoR1 and its downstream pathway genes, including AMPK, p-AMPK, and SIRT-1. miR-3908 enhances the process of breast cancer cell clonogenicity. miR-3908 exerts its effects on the proliferation and migration of MCF-7 cells, which are mediated by lipid rafts regulating AdipoR1's ability to bind Flotillin-1. miR-3908 is a crucial mediator of the migration process in breast cancer cells. Lipid rafts regulate the interactions between AdipoR1 and Flotillin-1 and then the migration process associated with miR-3908 in MCF-7 cells. Our findings suggest that targeting miR-3908 and the lipid raft, may be a promising strategy for the treatment and prevention of breast cancer.

Circulating miR-33a and miR-33b are up-regulated in familial hypercholesterolaemia in paediatric age.

PubMed

Martino, Francesco; Carlomosti, Fabrizio; Avitabile, Daniele; Persico, Luca; Picozza, Mario; Barillà, Francesco; Arca, Marcello; Montali, Anna; Martino, Eliana; Zanoni, Cristina; Parrotto, Sandro; Magenta, Alessandra

2015-12-01

Hypercholesterolaemia is one of the major causes of CVD (cardiovascular disease). It is associated with enhanced oxidative stress, leading to increased lipid peroxidation which in turn determines endothelial dysfunction and susceptibility to coronary vasoconstriction and atherosclerosis. Different miRNAs are involved in the pathogenesis of CVD and play an important role in inflammatory process control, therefore, together with atherogenic factors, they can stimulate atherosclerotic degeneration of the vessel walls of arteries. miR-33a and miR-33b play a pivotal role in a variety of biological processes including cholesterol homoeostasis, HDL (high-density lipoprotein)-cholesterol formation, fatty acid oxidation and insulin signalling. Our study aimed to determine whether circulating miR-33a and miR-33b expression was altered in familial hypercholesterolaemic children. Total RNA was extracted from plasma, and miR-33a and miR-33b were measured by quantitative real-time PCR. We found that miR-33a and miR-33b were significantly up-regulated in the plasma of 28 hypercholesterolaemic children compared with 25 healthy subjects (4.49±0.27-fold increase, P<0.001, and 3.21±0.39-fold increase, P<0.05 respectively), and for both miRNAs, a positive correlation with total cholesterol, LDL (low-density lipoprotein)-cholesterol, LDL-cholesterol/HDL-cholesterol ratio, apolipoprotein B, CRP (C-reactive protein) and glycaemia was found. OLS (ordinary least squares) regression analysis revealed that miR-33a was significantly affected by the presence of FH (familial hypercholesterolaemia), glycaemia and CRP (P<0.001, P<0.05 and P<0.05 respectively). The same analysis showed that miR-33b was significantly related to FH and CRP (P<0.05 and P<0.05 respectively). Although it is only explorative, the present study could be the first to point to the use of miR-33a and miR-33b as early biomarkers for cholesterol levels in childhood, once validated in independent larger cohorts. © 2015

GOES-R User Data Types and Structure

NASA Astrophysics Data System (ADS)

Royle, A. W.

2012-12-01

GOES-R meteorological data is provided to the operational and science user community through four main distribution mechanisms. The GOES-R Ground Segment (GS) generates a set of Level 1b (L1b) data from each of the six primary satellite instruments and formats the data into a direct broadcast stream known as GOES Rebroadcast (GRB). Terrestrially, cloud and moisture imagery data is provided to forecasters at the National Weather Service (NWS) through a direct interface to the Advanced Weather Interactive Processing System (AWIPS). A secondary pathway for the user community to receive data terrestrially is via NOAA's Environmental Satellite Processing and Distribution System (ESPDS) Product Distribution and Access (PDA) system. The ESPDS PDA will service the NWS and other meteorological users through a data portal, which provides both a subscription service and an ad hoc query capability. Finally, GOES-R data is made available to NOAA's Comprehensive Large Array-Data Stewardship System (CLASS) for long-term archive. CLASS data includes the L1b and L2+ products sent to PDA, along with the Level 0 data used to create these products, and other data used for product generation and processing. This session will provide a summary description of the data types and formats associated with each of the four primary distribution pathways for user data from GOES-R. It will discuss the resources that are being developed by GOES-R to document the data structures and formats. It will also provide a brief introduction to the types of metadata associated with each of the primary data flows.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

The GOES-R spacecraft stands vertically inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R ABI Optics Test

NASA Image and Video Library

2016-08-31

With the lights out, team members perform an optics test on the Advanced Baseline Imager, the primary optical instrument, on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. Carbon dioxide is sprayed on the imager to clean it and test its sensitivity. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R ABI Optics Test

NASA Image and Video Library

2016-08-31

Team members prepare for an optics test on the Advanced Baseline Imager, the primary optical instrument, on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. Carbon dioxide will be sprayed on the imager to clean it and test its sensitivity. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

The gputools package enables GPU computing in R.

PubMed

Buckner, Joshua; Wilson, Justin; Seligman, Mark; Athey, Brian; Watson, Stanley; Meng, Fan

2010-01-01

By default, the R statistical environment does not make use of parallelism. Researchers may resort to expensive solutions such as cluster hardware for large analysis tasks. Graphics processing units (GPUs) provide an inexpensive and computationally powerful alternative. Using R and the CUDA toolkit from Nvidia, we have implemented several functions commonly used in microarray gene expression analysis for GPU-equipped computers. R users can take advantage of the better performance provided by an Nvidia GPU. The package is available from CRAN, the R project's repository of packages, at http://cran.r-project.org/web/packages/gputools More information about our gputools R package is available at http://brainarray.mbni.med.umich.edu/brainarray/Rgpgpu

Systemic evaluation of cellular reprogramming processes exploiting a novel R-tool: eegc.

PubMed

Zhou, Xiaoyuan; Meng, Guofeng; Nardini, Christine; Mei, Hongkang

2017-08-15

Cells derived by cellular engineering, i.e. differentiation of induced pluripotent stem cells and direct lineage reprogramming, carry a tremendous potential for medical applications and in particular for regenerative therapies. These approaches consist in the definition of lineage-specific experimental protocols that, by manipulation of a limited number of biological cues-niche mimicking factors, (in)activation of transcription factors, to name a few-enforce the final expression of cell-specific (marker) molecules. To date, given the intricate complexity of biological pathways, these approaches still present imperfect reprogramming fidelity, with uncertain consequences on the functional properties of the resulting cells. We propose a novel tool eegc to evaluate cellular engineering processes, in a systemic rather than marker-based fashion, by integrating transcriptome profiling and functional analysis. Our method clusters genes into categories representing different states of (trans)differentiation and further performs functional and gene regulatory network analyses for each of the categories of the engineered cells, thus offering practical indications on the potential lack of the reprogramming protocol. eegc R package is released under the GNU General Public License within the Bioconductor project, freely available at https://bioconductor.org/packages/eegc/. christine.nardini.rsrc@gmail.com or hongkang.k.mei@gsk.com. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

Systemic evaluation of cellular reprogramming processes exploiting a novel R-tool: eegc

PubMed Central

Zhou, Xiaoyuan; Meng, Guofeng; Nardini, Christine; Mei, Hongkang

2017-01-01

Abstract Motivation Cells derived by cellular engineering, i.e. differentiation of induced pluripotent stem cells and direct lineage reprogramming, carry a tremendous potential for medical applications and in particular for regenerative therapies. These approaches consist in the definition of lineage-specific experimental protocols that, by manipulation of a limited number of biological cues—niche mimicking factors, (in)activation of transcription factors, to name a few—enforce the final expression of cell-specific (marker) molecules. To date, given the intricate complexity of biological pathways, these approaches still present imperfect reprogramming fidelity, with uncertain consequences on the functional properties of the resulting cells. Results We propose a novel tool eegc to evaluate cellular engineering processes, in a systemic rather than marker-based fashion, by integrating transcriptome profiling and functional analysis. Our method clusters genes into categories representing different states of (trans)differentiation and further performs functional and gene regulatory network analyses for each of the categories of the engineered cells, thus offering practical indications on the potential lack of the reprogramming protocol. Availability and Implementation eegc R package is released under the GNU General Public License within the Bioconductor project, freely available at https://bioconductor.org/packages/eegc/. Contact christine.nardini.rsrc@gmail.com or hongkang.k.mei@gsk.com Supplementary information Supplementary data are available at Bioinformatics online. PMID:28398503

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

The shipping container is lifted off the GOES-R spacecraft inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

The GOES-R spacecraft is revealed following its uncrating inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Does R&D pay?

PubMed

Cavalla, David; Minhas, Raman

2010-03-01

Pharmaceutical R&D is notoriously risky, lengthy and costly; moreover, it does not always produce products of blockbuster status. The conventional route of fully discovering, developing and marketing a new chemical entity is followed by the large pharmaceutical companies, whereas other organizations in the pharmaceutical sector--such as generic or specialty companies and biotechnology companies--only operate over portions of the full R&D process. Here, we compare the ten-year financial performance of these three subsectors through their price/earnings ratios and their return on capital metrics to understand which of these strategic alternatives offered the best return to investors. 2009 Elsevier Ltd. All rights reserved.

Preparing the Direct Broadcast Community for GOES-R

NASA Astrophysics Data System (ADS)

Dubey, K. F.; Baptiste, E.; Prasad, K.; Shin, H.

2012-12-01

The first satellite in the United States next generation weather satellite program, GOES-R, will be launched in 2015. SeaSpace Corporation is using our recent experience and lessons learned from bringing Suomi NPP-capable direct reception systems online, to similarly bring direct reception solutions to future GOES-R users. This includes earlier outreach to customers, due to the advance budgeting deadline for procurement in many agencies. With the cancellation of eGRB, all current GOES gvar customer will need a new direct readout system, with a new receiver, high powered processing subsystem, and a larger antenna in some locations. SeaSpace's preparations have also included communicating with program leaders in NOAA and NASA regarding direct readout specifications and the development of the borrowing process for the government-procured GRB emulator. At the request of NASA, SeaSpace has offered input towards the emulator check-out process, which is expected to begin in spring 2013. After the launch of Suomi NPP, SeaSpace found a need by non-traditional customers (such as customers with non-SeaSpace ground stations or those getting data via the NOAA archive), for a processing-only subsystem. In response to this need, SeaSpace developed such a solution for Suomi NPP users, and plans to do similar for GOES-R. This presentation will cover the steps that SeaSpace is undertaking to prepare the members of the direct reception community for reception and processing of GOES-R satellite data, and detail the solutions offered.

miR-181a and miR-630 regulate cisplatin-induced cancer cell death.

PubMed

Galluzzi, Lorenzo; Morselli, Eugenia; Vitale, Ilio; Kepp, Oliver; Senovilla, Laura; Criollo, Alfredo; Servant, Nicolas; Paccard, Caroline; Hupé, Philippe; Robert, Thomas; Ripoche, Hugues; Lazar, Vladimir; Harel-Bellan, Annick; Dessen, Philippe; Barillot, Emmanuel; Kroemer, Guido

2010-03-01

MicroRNAs (miRNA) are noncoding RNAs that regulate multiple cellular processes, including proliferation and apoptosis. We used microarray technology to identify miRNAs that were upregulated by non-small cell lung cancer (NSCLC) A549 cells in response to cisplatin (CDDP). The corresponding synthetic miRNA precursors (pre-miRNAs) per se were not lethal when transfected into A549 cells yet affected cell death induction by CDDP, C2-ceramide, cadmium, etoposide, and mitoxantrone in an inducer-specific fashion. Whereas synthetic miRNA inhibitors (anti-miRNAs) targeting miR-181a and miR-630 failed to modulate the response of A549 to CDDP, pre-miR-181a and pre-miR-630 enhanced and reduced CDDP-triggered cell death, respectively. Pre-miR-181a and pre-miR-630 consistently modulated mitochondrial/postmitochondrial steps of the intrinsic pathway of apoptosis, including Bax oligomerization, mitochondrial transmembrane potential dissipation, and the proteolytic maturation of caspase-9 and caspase-3. In addition, pre-miR-630 blocked early manifestations of the DNA damage response, including the phosphorylation of the ataxia-telangiectasia mutated (ATM) kinase and of two ATM substrates, histone H2AX and p53. Pharmacologic and genetic inhibition of p53 corroborated the hypothesis that pre-miR-630 (but not pre-miR-181a) blocks the upstream signaling pathways that are ignited by DNA damage and converge on p53 activation. Pre-miR-630 arrested A549 cells in the G0-G1 phase of the cell cycle, correlating with increased levels of the cell cycle inhibitor p27(Kip1) as well as with reduced proliferation rates and resulting in greatly diminished sensitivity of A549 cells to the late S-G2-M cell cycle arrest mediated by CDDP. Altogether, these results identify miR-181a and miR-630 as novel modulators of the CDDP response in NSCLC.

A biogenesis step upstream of Microprocessor controls miR-17~92 expression

PubMed Central

Du, Peng; Wang, Longfei; Sliz, Piotr; Gregory, Richard I.

2015-01-01

SUMMARY The precise control of miR-17~92 microRNA (miRNA) is essential for normal development and overexpression of certain miRNAs from this cluster is oncogenic. Here we find the relative expression of the six miRNAs processed from the primary (pri-miR-17~92) transcript is dynamically regulated during embryonic stem cell (ESC) differentiation. Pri-miR-17~92 is processed to a biogenesis intermediate, termed ‘progenitor-miRNA’ (pro-miRNA). Pro-miRNA is an efficient substrate for Microprocessor and is required to selectively license production of pre-miR-17, -18a, -19a, 20a, and -19b from this cluster. Two complementary cis-regulatory repression domains within pri-miR-17~92 are required for the blockade of miRNA processing through the formation of an autoinhibitory RNA conformation. The endonuclease CPSF3 (CPSF73), and the Spliceosome-associated ISY1 are responsible for pro-miRNA biogenesis and expression of all miRNAs within the cluster except miR-92. Thus, developmentally regulated pro-miRNA processing is key step controlling miRNA expression and explains the posttranscriptional control of miR-17~92 expression in development. PMID:26255770

INFLUENCE OF IRON CHELATION ON R1 AND R2 CALIBRATION CURVES IN GERBIL LIVER AND HEART

PubMed Central

Wood, John C.; Aguilar, Michelle; Otto-Duessel, Maya; Nick, Hanspeter; Nelson, Marvin D.; Moats, Rex

2008-01-01

MRI is gaining increasing importance for the noninvasive quantification of organ iron burden. Since transverse relaxation rates depend on iron distribution as well as iron concentration, physiologic and pharmacologic processes that alter iron distribution could change MRI calibration curves. This paper compares the effect of three iron chelators, deferoxamine, deferiprone, and deferasirox on R1 and R2 calibration curves according to two iron loading and chelation strategies. 33 Mongolian gerbils underwent iron loading (iron dextran 500 mg/kg/wk) for 3 weeks followed by 4 weeks of chelation. An additional 56 animals received less aggressive loading (200 mg/kg/week) for 10 weeks, followed by 12 weeks of chelation. R1 and R2 calibration curves were compared to results from 23 iron-loaded animals that had not received chelation. Acute iron loading and chelation biased R1 and R2 from the unchelated reference calibration curves but chelator-specific changes were not observed, suggesting physiologic rather than pharmacologic differences in iron distribution. Long term chelation deferiprone treatment increased liver R1 50% (p<0.01), while long term deferasirox lowered liver R2 30.9% (p<0.0001). The relationship between R1 and R2 and organ iron concentration may depend upon the acuity of iron loading and unloading as well as the iron chelator administered. PMID:18581418

Up-Regulation of miR-21, miR-25, miR-93, and miR-106b in Gastric Cancer

PubMed

LArki, Pegah; Ahadi, Alireza; Zare, Ali; Tarighi, Shahriar; Zaheri, Mahrokh; Souri, Mojgan; Zali, Mohammad Reza; Ghaedi, Hamid; Omrani, Mir Davood

2018-06-03

Differential expression profile of microRNAs (miRNAs) could be a diagnosis signature for the monitoring of gastric cancer (GC) progression. In this study, we focus on the comparison of expression levels of miR-21, miR-25, miR-93, miR-106b, and miR-375 during the sequential pattern of GC development, including normal gastric, gastric dysplasia, and GC sample. We used SYBR Green-based quantitative-PCR to quantify miRNAs expression. Our analysis revealed the increased expression levels of miR-21 (p = 0.034), miR-25 (p = 0.0003) miR-93 (p = 0.0406), and miR-106b (p = 0.023) in GC samples. In addition, GC patients with positive lymph node metastasis showed the up-regulation of miR-25, miR-93, and miR-106b (p < 0.05). Our findings suggested that miR-21, miR-25, miR-93, and miR-106b altered expression in GC, and some of them may be further investigated as biomarkers for GC early detection and prognosis prediction.

Investigation of a miRNA-Induced Gene Silencing Technique in Petunia Reveals Alterations in miR173 Precursor Processing and the Accumulation of Secondary siRNAs from Endogenous Genes.

PubMed

Han, Yao; Zhang, Bin; Qin, Xiaoting; Li, Mingyang; Guo, Yulong

2015-01-01

MIGS (miRNA-induced gene silencing) is a straightforward and efficient gene silencing technique in Arabidopsis. It works by exploiting miR173 to trigger the production of phasiRNAs (phased small interfering RNAs). MIGS can be used in plant species other than Arabidopsis by co-expression of miR173 and target gene fragments fused to an upstream miR173 target site. However, the efficiency and technical mechanisms have not been thoroughly investigated in other plants. In this work, two vectors, pMIGS-chs and pMIGS-pds, were constructed and transformed into petunia plants. The transgenic plants showed CHS (chalcone synthase) and PDS (phytoene desaturase) gene-silencing phenotypes respectively, indicating that MIGS functions in petunia. MIGS-chs plants were used to investigate the mechanisms of this technique in petunia. Results of 5'- RACE showed that the miR173 target site was cleaved at the expected position and that endogenous CHS genes were cut at multiple positions. Small RNA deep sequencing analysis showed that the processing of Arabidopsis miR173 precursors in MIGS-chs transgenic petunia plants did not occur in exactly the same way as in Arabidopsis, suggesting differences in the machinery of miRNA processing between plant species. Small RNAs in-phase with the miR173 cleavage register were produced immediately downstream from the cleavage site and out-of-phase small RNAs were accumulated at relatively high levels from processing cycle 5 onwards. Secondary siRNAs were generated from multiple sites of endogenous CHS-A and CHS-J genes, indicating that miR173 cleavage induced siRNAs have the same ability to initiate siRNA transitivity as the siRNAs functioning in co-suppression and hpRNA silencing. On account of the simplicity of vector construction and the transitive amplification of signals from endogenous transcripts, MIGS is a good alternative gene silencing method for plants, especially for silencing a cluster of homologous genes with redundant functions.

Investigation of a miRNA-Induced Gene Silencing Technique in Petunia Reveals Alterations in miR173 Precursor Processing and the Accumulation of Secondary siRNAs from Endogenous Genes

PubMed Central

Han, Yao; Zhang, Bin; Qin, Xiaoting; Li, Mingyang; Guo, Yulong

2015-01-01

MIGS (miRNA-induced gene silencing) is a straightforward and efficient gene silencing technique in Arabidopsis. It works by exploiting miR173 to trigger the production of phasiRNAs (phased small interfering RNAs). MIGS can be used in plant species other than Arabidopsis by co-expression of miR173 and target gene fragments fused to an upstream miR173 target site. However, the efficiency and technical mechanisms have not been thoroughly investigated in other plants. In this work, two vectors, pMIGS-chs and pMIGS-pds, were constructed and transformed into petunia plants. The transgenic plants showed CHS (chalcone synthase) and PDS (phytoene desaturase) gene-silencing phenotypes respectively, indicating that MIGS functions in petunia. MIGS-chs plants were used to investigate the mechanisms of this technique in petunia. Results of 5′- RACE showed that the miR173 target site was cleaved at the expected position and that endogenous CHS genes were cut at multiple positions. Small RNA deep sequencing analysis showed that the processing of Arabidopsis miR173 precursors in MIGS-chs transgenic petunia plants did not occur in exactly the same way as in Arabidopsis, suggesting differences in the machinery of miRNA processing between plant species. Small RNAs in-phase with the miR173 cleavage register were produced immediately downstream from the cleavage site and out-of-phase small RNAs were accumulated at relatively high levels from processing cycle 5 onwards. Secondary siRNAs were generated from multiple sites of endogenous CHS-A and CHS-J genes, indicating that miR173 cleavage induced siRNAs have the same ability to initiate siRNA transitivity as the siRNAs functioning in co-suppression and hpRNA silencing. On account of the simplicity of vector construction and the transitive amplification of signals from endogenous transcripts, MIGS is a good alternative gene silencing method for plants, especially for silencing a cluster of homologous genes with redundant functions. PMID

Development of a prototype chest digital tomosynthesis (CDT) R/F system with fast image reconstruction using graphics processing unit (GPU) programming

NASA Astrophysics Data System (ADS)

Choi, Sunghoon; Lee, Seungwan; Lee, Haenghwa; Lee, Donghoon; Choi, Seungyeon; Shin, Jungwook; Seo, Chang-Woo; Kim, Hee-Joung

2017-03-01

Digital tomosynthesis offers the advantage of low radiation doses compared to conventional computed tomography (CT) by utilizing small numbers of projections ( 80) acquired over a limited angular range. It produces 3D volumetric data, although there are artifacts due to incomplete sampling. Based upon these characteristics, we developed a prototype digital tomosynthesis R/F system for applications in chest imaging. Our prototype chest digital tomosynthesis (CDT) R/F system contains an X-ray tube with high power R/F pulse generator, flat-panel detector, R/F table, electromechanical radiographic subsystems including a precise motor controller, and a reconstruction server. For image reconstruction, users select between analytic and iterative reconstruction methods. Our reconstructed images of Catphan700 and LUNGMAN phantoms clearly and rapidly described the internal structures of phantoms using graphics processing unit (GPU) programming. Contrast-to-noise ratio (CNR) values of the CTP682 module of Catphan700 were higher in images using a simultaneous algebraic reconstruction technique (SART) than in those using filtered back-projection (FBP) for all materials by factors of 2.60, 3.78, 5.50, 2.30, 3.70, and 2.52 for air, lung foam, low density polyethylene (LDPE), Delrin® (acetal homopolymer resin), bone 50% (hydroxyapatite), and Teflon, respectively. Total elapsed times for producing 3D volume were 2.92 s and 86.29 s on average for FBP and SART (20 iterations), respectively. The times required for reconstruction were clinically feasible. Moreover, the total radiation dose from our system (5.68 mGy) was lower than that of conventional chest CT scan. Consequently, our prototype tomosynthesis R/F system represents an important advance in digital tomosynthesis applications.

Biotransformation of (-)-(1R,4S)-Menthone and (+)-(1S,4R)-Menthone by the Common Cutworm Spodoptera litura Larvae.

PubMed

Marumoto, Shinsuke; Okuno, Yoshiharu; Hagiwara, Yuki; Miyazawa, Mitsuo

2017-08-01

Using biotransformation as a biocatalytic process has the advantage of being able to proceed under mild conditions and with high regio- and enantioselectivity. This study investigated the biotransformation of (-)-(1R,4S)-menthone (1) and (+)-(1S,4R)-menthone (2) by Spodoptera litura larvae. Compound 1 was converted to (-)-(1R,4S)-7-hydroxymenthone (1-1), (+)-(1R,3S,4S)-7-hydroxyneomenthol (1-2) and (-)-(1R,4S,8R)-p-menth-3-one-9-oic acid (1-3). The metabolism of substrate 2 generated three enantiomers of the above metabolites, designated as 2-1 to 2-3, respectively. The C-9 position of (-)-menthone and (+)-menthone was oxidized to carboxylic acid by S. litura, which is a metabolic pathway not observed in any other example of biocatalysis.

GOES-R ITAR Photos for Media Day

NASA Image and Video Library

2016-09-26

The Geostationary Operational Environmental Satellite (GOES-R) is undergoing final launch preparations prior to fueling inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

The GOES-R spacecraft is inspected after being uncrated and raised to vertical inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

Team members monitor progress as the GOES-R spacecraft is lifted from horizontal to vertical inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

Team members monitor progress as the GOES-R spacecraft is raised to vertical inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Uncrating and Move to Vertical

NASA Image and Video Library

2016-08-23

Team members remove a protective plastic covering from the GOES-R spacecraft inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA Geostationary Operational Environmental Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Integrative knowledge management to enhance pharmaceutical R&D.

PubMed

Marti-Solano, Maria; Birney, Ewan; Bril, Antoine; Della Pasqua, Oscar; Kitano, Hiroaki; Mons, Barend; Xenarios, Ioannis; Sanz, Ferran

2014-04-01

Information technologies already have a key role in pharmaceutical research and development (R&D), but achieving substantial advances in their use and effectiveness will depend on overcoming current challenges in sharing, integrating and jointly analysing the range of data generated at different stages of the R&D process.

Weathering process in Sør Rondane Mountains, East Antarctica

NASA Astrophysics Data System (ADS)

Kanamaru, T.; Suganuma, Y.; Oiwane, H.; Miura, M.; Okuno, J.; Hayakawa, H.

2016-12-01

Weathering process under the hyper-arid and hypothermal environment is a key to understand the geomorphogic process and landscape evolution in Antarctica and on Mars. A nunber of studies have focused on weathering process of basaltic rocks in Antarctica, however, the nature of the weathering process of plutonic type rock, a common rock type on the Earth, have been less focused and remain unclear. Here, we report the physical/chemical weathering process of the granitic rocks obtained from Dronning Maud Land in East Antarctica based on a multiplicity of petrological approaches. Loss on Ignition (LOI) and major element composition of the crust and core of the rock samples indicate that chemical weathering process in this area seems to be very limited. The microscopic observations and laser-Raman micro spectroscopy for thin sections from the crust and core indicate that goethite grains are formed mainly in the vein around the crust, which is consistent with the higher Fe3+/Fe2+ contrast from the core to crust. A negative correlation between the rock hardness and color strength index (CSI) values also indicate that crust of rock samples tend to less hard than core due to cracking of the rock samples and following goethite formation. On the other hand, EPMA analysis indicates that original Fe-Ti oxide grains in the core of rock samples are damaged by weathering, and altered to hematite, and to non-stoichiometric Fe-Ti compound associated with ilmenite grans in case of the higher relative height samples. These reveal that the weathering process of the plutonic rocks under the hyper-cold and hypothermal environment are mainly controlled by oxidation, including iron hydroxide formation in the veins formed by mechanical distraction, and Fe-Ti oxide alteration in rock interior.

CAVIAR: an R package for checking, displaying and processing wood-formation-monitoring data.

PubMed

Rathgeber, Cyrille B K; Santenoise, Philippe; Cuny, Henri E

2018-05-19

In the last decade, the pervasive question of climate change impacts on forests has revived investigations on intra-annual dynamics of wood formation, involving disciplines such as plant ecology, tree physiology and dendrochronology. This resulted in the creation of many research groups working on this topic worldwide and a rapid increase in the number of studies and publications. Wood-formation-monitoring studies are generally based on a common conceptual model describing xylem cell formation as the succession of four differentiation phases (cell division, cell enlargement, cell wall thickening and mature cells). They generally use the same sampling techniques, sample preparation methods and anatomical criteria to separate between differentiation zones and discriminate and count forming xylem cells, resulting in very similar raw data. However, the way these raw data are then processed, producing the elaborated data on which statistical analyses are performed, still remains quite specific to each individual study. Thereby, despite very similar raw data, wood-formation-monitoring studies yield results that are still quite difficult to compare. CAVIAR-an R package specifically dedicated to the verification, visualization and manipulation of wood-formation-monitoring data-can help to improve this situation. Initially, CAVIAR was built to provide efficient algorithms to compute critical dates of wood formation phenology for conifers growing in temperate and cold environments. Recently, we developed it further to check, display and process wood-formation-monitoring data. Thanks to new and upgraded functions, raw data can now be consistently verified, standardized and modelled (using logistic regressions and Gompertz functions), in order to describe wood phenology and intra-annual dynamics of tree-ring formation. We believe that CAVIAR will help strengthening the science of wood formation dynamics by effectively contributing to the standardization of its concepts and

75 FR 14069 - Amendment of Using Agency for Restricted Areas R-3005A, R-3305B, R-3005C, R-3005D and R-3005E...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-24

...; Airspace Docket No. 10-ASO-19] RIN 2120-AA66 Amendment of Using Agency for Restricted Areas R-3005A, R-3305B, R-3005C, R-3005D and R-3005E; Fort Stewart, GA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action changes the using agency of restricted areas R- 3005A, R-3005B...

Dynamic Evolution in the Symbiotic R Aquarii

NASA Technical Reports Server (NTRS)

DePasquale, J. M.; Nichols, J. S.; Kellogg, E. M.

2007-01-01

We report on multiple Chandra observations spanning a period of 5 years as well as a more recent XMM observation of the nearby symbiotic binary R Aqr. Spectral analysis of these four observations reveals considerable variability in hardness ratios and in the strength and ionization levels of emission lines which provides insight into white dwarf accretion processes as well as continuum and line formation mechanisms. Chandra imaging of the central source also shows the formation and evolution of a new south west jet. This growing body of high-resolution X-ray data of R Aqr provides a unique glimpse into white dwarf wind-accretion processes and jet formation.

Research in Stochastic Processes

DTIC Science & Technology

1988-08-31

stationary sequence, Stochastic Proc. Appl. 29, 1988, 155-169 T. Hsing, J. Husler and M.R. Leadbetter, On the exceedance point process for a stationary...Nandagopalan, On exceedance point processes for "regular" sample functions, Proc. Volume, Oberxolfach Conf. on Extreme Value Theory, J. Husler and R. Reiss...exceedance point processes for stationary sequences under mild oscillation restrictions, Apr. 88. Obermotfach Conf. on Extremal Value Theory. Ed. J. HUsler

Dysregulated expression of miR-101b and miR-26b lead to age-associated increase in LPS-induced COX-2 expression in murine macrophage.

PubMed

Liu, Dan; Wang, Dongsheng; Xu, Zhenbiao; Gao, Jing; Liu, Min; Liu, Yanxin; Jiang, Minghong; Zheng, Dexian

2015-10-01

Aging is the natural process of decline in physiological structure and function of various molecules, cells, tissues, and organs. Growing evidence indicates that increased immune genetic diversity and dysfunction of immune system cause aging-related pathophysiological process with the growth of age. In the present study, we observed that LPS-induced higher activation of cyclooxygenase (COX)-2 promoter is associated with the upregulated binding activity of nuclear factor kappa B (NF-κB) in peritoneal macrophages of aged mice than young ones. Additionally, COX-2 is a direct target of miR-101b and miR-26b in the macrophages. Significant upregulation of miR-101b and miR-26b effectively prevented LPS-induced excessive expression of COX-2 in the young mice. Because these negative regulatory factors were unresponsive to LPS stimulation, the levels of COX-2 were markedly higher in the macrophages of aged mice. Further study showed that NF-κB activation contributed to the increase in the expression of miR-101b and miR-26b in the LPS-stimulated macrophages of young mice, but not aged ones. Moreover, histone deacetylase (HDAC) inhibitor trichostatin A (TSA) upregulated expression of miR-101b and miR-26b in the aged mouse macrophages only, but not the young cells. This demonstrated that HDAC suppressed the expression of miR-101b and miR-26b in the LPS-treated macrophages of aged mice and contributed to the aging process. TSA-induced increased expression of miR-101b and miR-26b could further suppress COX-2 expression. These findings provide novel evidence on the regulation of immune senescence and miR-101b and miR-26b, which might be promising targets in treating aged-related inflammatory diseases. Epigenetic regulation of the microRNAs (miRNAs) provides an important evidence for the treatment of innate inflammatory disease with HDAC inhibitors in elderly.

Pharmacokinetics and Metabolism of (R,R)-Methoxyfenoterol in Rat

PubMed Central

Siluk, Danuta; Mager, Donald E.; Kim, Hee Seung; Wang, Yan; Furimsky, Anna M.; Ta, Amy; Iyer, Lalitha V.; Green, Carol E.; Wainer, Irving W.

2010-01-01

(R,R)-Fenoterol (Fen), a β2-adrenoceptor agonist, is under clinical investigation in the treatment of congestive heart disease. The pharmacokinetics and metabolism of the 4-methoxyphenyl derivative of (R,R)-Fen, (R,R)-MFen, have been determined following intravenous and oral administration to the rat and compared with corresponding results obtained with (R,R)-Fen. Results of the study suggest that (R,R)-MFen can offer pharmacokinetic and metabolic advantages in comparison to an earlier (R,R)-Fen.The oral administration revealed that the net exposure of (R,R)-MFen was about three-fold higher than that of (R,R)-Fen (7.2 versus 2.3 min × nmol ml-1), while intravenous administration proved that the clearance was significantly reduced, 48 versus 146 ml min-1 kg-1, the T1/2 was significantly longer, 152.9 versus 108.9 min and the area under the curve (AUC) was significantly increased, 300 versus 119 min × nmol ml-1.(R,R)-MFen was primarily cleared by glucuronidation associated with significant presystemic glucuronidation of the compound. After intravenous and oral administration of (R,R)-MFen, (R,R)-Fen and (R,R)-Fen-G were detected in the urine samples indicating that (R,R)-MFen was O-demethylated and subsequently conjugated to (R,R)-Fen-G. The total (R,R)-Fen and (R,R)-Fen-G as a percentage of the dose after intravenous administration was 3.6% while after oral administration was 0.3%, indicating that only a small fraction of the drug escaped presystemic glucuronidation and was available for O-demethylation.The glucuronidation pattern was confirmed by the results from in vitro studies where incubation of (R,R)-MFen with rat hepatocytes produced (R,R)-MFen-G, (R,R)-Fen and (R,R)-Fen-G, while incubation with rat intestinal microsomes only resulted in the formation of (R,R)-MFen-G. PMID:20039779

Pharmacokinetics and metabolism of (R,R)-methoxyfenoterol in rat.

PubMed

Siluk, D; Mager, D E; Kim, H S; Wang, Y; Furimsky, A M; Ta, A; Iyer, L V; Green, C E; Wainer, I W

2010-03-01

(R,R)-fenoterol (Fen), a beta(2)-adrenoceptor agonist, is under clinical investigation in the treatment of congestive heart disease. The pharmacokinetics and metabolism of the 4-methoxyphenyl derivative of (R,R)-Fen, (R,R)-MFen, have been determined following intravenous and oral administration to the rat and compared with corresponding results obtained with (R,R)-Fen. Results from the study suggest that (R,R)-MFen can offer pharmacokinetic and metabolic advantages in comparison to an earlier (R,R)-Fen. The oral administration revealed that the net exposure of (R,R)-MFen was about three-fold higher than that of (R,R)-Fen (7.2 versus 2.3 min x nmol ml(-1)), while intravenous administration proved that the clearance was significantly reduced, 48 versus 146 ml min(-1) kg(-1), the T(1/2) was significantly longer, 152.9 versus 108.9 min, and the area under the curve (AUC) was significantly increased, 300 versus 119 min x nmol ml(-1). (R,R)-MFen was primarily cleared by glucuronidation associated with significant presystemic glucuronidation of the compound. After intravenous and oral administration of (R,R)-MFen, (R,R)-Fen and (R,R)-Fen-G were detected in the urine samples indicating that (R,R)-MFen was O-demethylated and subsequently conjugated to (R,R)-Fen-G. The total (R,R)-Fen and (R,R)-Fen-G as a percentage of the dose after intravenous administration was 3.6%, while after oral administration was 0.3%, indicating that only a small fraction of the drug escaped presystemic glucuronidation and was available for O-demethylation. The glucuronidation pattern was confirmed by the results from in vitro studies where incubation of (R,R)-MFen with rat hepatocytes produced (R,R)-MFen-G, (R,R)-Fen and (R,R)-Fen-G, while incubation with rat intestinal microsomes only resulted in the formation of (R,R)-MFen-G.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members install the Advanced Base Line Imager, the primary optical instrument, on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

The Advanced Base Line Imager, the primary optical instrument, has been installed on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Closed string tachyon driving f(R) cosmology

NASA Astrophysics Data System (ADS)

Wang, Peng; Wu, Houwen; Yang, Haitang

2018-05-01

To study quantum effects on the bulk tachyon dynamics, we replace R with f(R) in the low-energy effective action that couples gravity, the dilaton, and the bulk closed string tachyon of bosonic closed string theory and study properties of their classical solutions. The α' corrections of the graviton-dilaton-tachyon system are implemented in the f(R). We obtain the tachyon-induced rolling solutions and show that the string metric does not need to remain fixed in some cases. In the case with H( t=‑∞ ) = , only the R and R2 terms in f(R) play a role in obtaining the rolling solutions with nontrivial metric. The singular behavior of more classical solutions are investigated and found to be modified by quantum effects. In particular, there could exist some classical solutions, in which the tachyon field rolls down from a maximum of the tachyon potential while the dilaton expectation value is always bounded from above during the rolling process.

R&D Alert. Volume 7, Number 2, 2005

ERIC Educational Resources Information Center

White, Noel, Ed.

2005-01-01

"R&D Alert" covers issues affecting schools in the Western Regional Educational Laboratory's four-state region--Arizona, California, Nevada, and Utah--and throughout the United States. This issue of "R&D Alert" shares what WestEd is learning from a sample of their latest work, focusing on three points in the process:…

Spermatozoa Expression of piR-31704, piR-39888, and piR-40349 and Their Correlation to Sperm Concentration and Fertilization Rate After ICSI.

PubMed

Cui, Long; Fang, Li; Shi, Biwei; Qiu, Sunquan; Ye, Yinghui

2018-05-01

To investigate the relationship between spermatozoa PIWI-interacting RNAs (piRNAs) levels and semen parameters and to evaluate the role of expression of piRNAs on fertilization and embryo development after intracytoplasmic sperm injection (ICSI) treatment. One hundred and eighty-six patients with idiopathic male infertility who had undergone first ICSI cycles were enrolled in our study. The levels of piRNAs in spermatozoa were measured by real-time polymerase chain reaction. Semen parameters, including sperm concentration, motility, and morphology, were evaluated. The rates of fertilization, early cleavage, and day 3 good-quality embryo were calculated to assess embryo development potential. Spermatozoa levels of piR-31704 and piR-39888 were decreased in male factor infertility group as compared with control group (for piR-31704, P = .027 and for piR-39888, P = .041, respectively). And these 2 piRNAs were expressed at higher levels in patients with normal sperm concentration compared with subnormal sperm concentration group (for piR-31704, P = .042; for piR-39888, P = .047, respectively), while there were no correlation between the 3 piRNAs expression levels in spermatozoa and the rates of sperm progressive motility and normal sperm morphology. There were significant increases in the levels of all 3 piRNAs in spermatozoa from the group with higher 2PN rates (for piR-31704, P = .002; for piR-39888, P < .001; for piR-40349, P < .001; respectively), but there was no correlation between spermatozoa levels of these 3 piRNAs and the rates of embryo early cleavage, day 3 good-quality embryos and pregnancy. Spermatozoa piRNA levels correlate with sperm concentration and fertilization rate after ICSI. Paternal piRNAs may play a role in fertilization process.

Osmium isotope evidence for uniform distribution of s- and r-process components in the early solar system

NASA Astrophysics Data System (ADS)

Yokoyama, Tetsuya; Rai, Vinai K.; Alexander, Conel M. O'D.; Lewis, Roy S.; Carlson, Richard W.; Shirey, Steven B.; Thiemens, Mark H.; Walker, Richard J.

2007-07-01

We have precisely measured Os isotopic ratios in bulk samples of five carbonaceous, two enstatite and two ordinary chondrites, as well as the acid-resistant residues of three carbonaceous chondrites. All bulk meteorite samples have uniform 186Os/ 188Os, 188Os/ 189Os and 190Os/ 189Os ratios, when decomposed by an alkaline fusion total digestion technique. These ratios are also identical to estimates for Os in the bulk silicate Earth. Despite Os isotopic homogeneity at the bulk meteorite scale, acid insoluble residues of three carbonaceous chondrites are enriched in 186Os, 188Os and 190Os, isotopes with major contributions from stellar s-process nucleosynthesis. Conversely, these isotopes are depleted in acid soluble portions of the same meteorites. The complementary enriched and depleted fractions indicate the presence of at least two types of Os-rich components in these meteorites, one enriched in Os isotopes produced by s-process nucleosynthesis, the other enriched in isotopes produced by the r-process. Presolar silicon carbide is the most probable host for the s-process-enriched Os present in the acid insoluble residues. Because the enriched and depleted components present in these meteorites are combined in proportions resulting in a uniform chondritic/terrestrial composition, it requires that disparate components were thoroughly mixed within the solar nebula at the time of the initiation of planetesimal accretion. This conclusion contrasts with evidence from the isotopic compositions of some other elements (e.g., Sm, Nd, Ru, Mo) that suggests heterogeneous distribution of matter with disparate nucleosynthetic sources within the nebula.

Requirements Analysis for Large Ada Programs: Lessons Learned on CCPDS- R

DTIC Science & Technology

1989-12-01

when the design had matured and This approach was not optimal from the formal the SRS role was to be the tester’s contract, implemen- testing and...on the software development CPU processing load. These constraints primar- process is the necessity to include sufficient testing ily affect algorithm...allocations and timing requirements are by-products of the software design process when multiple CSCls are a P R StrR eSOFTWARE ENGINEERING executed within

A Research Guide on National Board Certification[R] of Teachers

ERIC Educational Resources Information Center

National Board for Professional Teaching Standards, 2007

2007-01-01

The National Board for Professional Teaching Standards[R] (NBPTS) has always welcomed scrutiny of the National Board Certification[R] process and the impact that National Board Certified Teachers[R] (NBCTs) have on teaching and learning. As a result, in the 20 years since NBPTS was founded, National Board Certification has become one of the most…

Simple synthesis of graphene nanocomposites MgO-rGO and Fe2O3-rGO for multifunctional applications

NASA Astrophysics Data System (ADS)

Abdel-Aal, Seham K.; Ionov, Andrey; Mozhchil, R. N.; Naqvi, Alim H.

2018-05-01

Hummer's method was used to prepare graphene oxide (GO) by chemical exfoliation of graphite. Simple precipitation method was used for the preparation of hybrid nanocomposites MgO-rGO and Fe2O3-rGO. A 0.3 Molar of corresponding metal nitrate solution and GO solution are used for the preparation process. XRD, FT-IR, and XPS were used to characterize the prepared nanocomposites. The reduction of GO into reduced rGO in the formed nanocomposites was confirmed. Morphological characterization showed the formation of needle-shaped nanocrystals of MgO successfully grown on graphene nanosheet with average crystallite size 8.4 nm. Hematite nanocomposite Fe2O3-rGO forms rod-shaped crystals with average crystallite size 27.5 nm. The saturation magnetization observed for Fe2O3-rGO is less than reported value for the pure Fe2O3 nanoparticles. Thermal properties of as-prepared hybrid nanocomposites MgO-rGO and Fe2O3-rGO showed thermal stability of the prepared nanocomposite over long range of temperature.

R/V Maurice Ewing retires

NASA Astrophysics Data System (ADS)

Diebold, John

2005-07-01

The R/V Maurice Ewing came into port for the last time on 10 March 2005, tying up at Quonset Point, R.I., astern of the ship slated to be her replacement (Figure 1). M/V Western Legend (Figure 1, left) will, during fall and winter of 2005-2006, be converted as R/V Marcus G. Langseth, and will replace the Maurice Ewing (Figure 1, right) as the primary seismic research vessel within the U.S. academic research vessel fleet.During its distinguished 15-year career, Ewing's operations added fundamentally to the knowledge and understanding of solid Earth dynamics and structure. Ewing began life as the M/V Bernier, and performed seismic offshore exploration for Petro Canada. In an innovative process, which included initialization provided by Columbia University, the U.S. National Science Foundation (NSF) acquired Bernier in 1989, and the ship's title passed to NSF in 1990. Bernier was converted into R/V Ewing for a total expenditure (approximately $12 million) far below the cost of building and outfitting a new seismic research ship.

Variable threshold method for ECG R-peak detection.

PubMed

Kew, Hsein-Ping; Jeong, Do-Un

2011-10-01

In this paper, a wearable belt-type ECG electrode worn around the chest by measuring the real-time ECG is produced in order to minimize the inconvenient in wearing. ECG signal is detected using a potential instrument system. The measured ECG signal is transmits via an ultra low power consumption wireless data communications unit to personal computer using Zigbee-compatible wireless sensor node. ECG signals carry a lot of clinical information for a cardiologist especially the R-peak detection in ECG. R-peak detection generally uses the threshold value which is fixed. There will be errors in peak detection when the baseline changes due to motion artifacts and signal size changes. Preprocessing process which includes differentiation process and Hilbert transform is used as signal preprocessing algorithm. Thereafter, variable threshold method is used to detect the R-peak which is more accurate and efficient than fixed threshold value method. R-peak detection using MIT-BIH databases and Long Term Real-Time ECG is performed in this research in order to evaluate the performance analysis.

Extracellular Identification of a Processed Type II ComR/ComS Pheromone of Streptococcus mutans

PubMed Central

Khan, Rabia; Rukke, Håkon V.; Ricomini Filho, Antonio Pedro; Fimland, Gunnar; Arntzen, Magnus Ø.; Thiede, Bernd

2012-01-01

The competence-stimulating peptide (CSP) and the sigX-inducing peptide (XIP) are known to induce Streptococcus mutans competence for genetic transformation. For both pheromones, direct identification of the native peptides has not been accomplished. The fact that extracellular XIP activity was recently observed in a chemically defined medium devoid of peptides, as mentioned in an accompanying paper (K. Desai, L. Mashburn-Warren, M. J. Federle, and D. A. Morrison, J. Bacteriol. 194:3774–3780, 2012), provided ideal conditions for native XIP identification. To search for the XIP identity, culture supernatants were filtered to select for peptides of less than 3 kDa, followed by C18 extraction. One peptide, not detected in the supernatant of a comS deletion mutant, was identified by tandem mass spectrometry (MS/MS) fragmentation as identical to the ComS C-terminal sequence GLDWWSL. ComS processing did not require Eep, a peptidase involved in processing or import of bacterial small hydrophobic peptides, since eep deletion had no inhibitory effect on XIP production or on synthetic XIP response. We investigated whether extracellular CSP was also produced. A reporter assay for CSP activity detection, as well as MS analysis of supernatants, revealed that CSP was not present at detectable levels. In addition, a mutant with deletion of the CSP-encoding gene comC produced endogenous XIP levels similar to those of a nondeletion mutant. The results indicate that XIP pheromone production is a natural phenomenon that may occur in the absence of natural CSP pheromone activity and that the heptapeptide GLDWWSL is an extracellular processed form of ComS, possibly the active XIP pheromone. This is the first report of direct identification of a ComR/ComS pheromone. PMID:22609914

MiR-126 and miR-126* regulate shear-resistant firm leukocyte adhesion to human brain endothelium

PubMed Central

Cerutti, Camilla; Edwards, Laura J.; de Vries, Helga E.; Sharrack, Basil; Male, David K.; Romero, Ignacio A.

2017-01-01

Leukocyte adhesion to brain endothelial cells, the blood-brain barrier main component, is a critical step in the pathogenesis of neuroinflammatory diseases such as multiple sclerosis (MS). Leukocyte adhesion is mediated mainly by selectins, cell adhesion molecules and chemokines induced by pro-inflammatory cytokines such as TNFα and IFNγ, but the regulation of this process is not fully clear. This study investigated the regulation of firm leukocyte adhesion to human brain endothelium by two different brain endothelial microRNAs (miRs), miR-126 and miR-126*, that are downregulated by TNFα and IFNγ in a human brain endothelial cell line, hCMEC/D3. Using a leukocyte adhesion in vitro assay under shear forces mimicking blood flow, we observed that reduction of endothelial miR-126 and miR-126* enhanced firm monocyte and T cell adhesion to hCMEC/D3 cells, whereas their increased expression partially prevented THP1, Jurkat and primary MS patient-derived PBMC firm adhesion. Furthermore, we observed that miR-126* and miR-126 downregulation increased E-selectin and VCAM1, respectively, while miR-126 overexpression reduced VCAM1 and CCL2 expression by hCMEC/D3 cells, suggesting that these miRs regulate leukocyte adhesion by modulating the expression of adhesion-associated endothelial mRNA targets. Hence, human brain endothelial miR-126 and miR-126* could be used as a therapeutic tool to reduce leukocyte adhesion and thus reduce neuroinflammation. PMID:28358058

Effects of low frequency repetitive transcranial magnetic stimulation (rTMS) on gamma frequency oscillations and event-related potentials during processing of illusory figures in autism.

PubMed

Sokhadze, Estate M; El-Baz, Ayman; Baruth, Joshua; Mathai, Grace; Sears, Lonnie; Casanova, Manuel F

2009-04-01

Previous studies by our group suggest that the neuropathology of autism is characterized by a disturbance of cortical modularity. In this model a decrease in the peripheral neuropil space of affected minicolumns provides for an inhibitory deficit and a readjustment in their signal to noise bias during information processing. In this study we proposed using low frequency transcranial magnetic stimulation (rTMS) as a way increasing the surround inhibition of minicolumns in autism. Thirteen patients (ADOS and ADI-R diagnosed) and equal number of controls participated in the study. Repetitive TMS was delivered at 0.5 Hz, 2 times per week for 3 weeks. Outcome measures based on event-related potentials (ERP), induced gamma activity, and behavioral measures showed significant post-TMS improvement. The results suggest that rTMS offers a potential therapeutic intervention for autism.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members prepare the Advanced Base Line Imager, the primary optical instrument, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Containerless Processing in Reduced Gravity Using the TEMPUS Facility during MSL-1 and MSL-1R

NASA Technical Reports Server (NTRS)

Rogers, Jan R.

1998-01-01

Containerless processing provides a high purity environment for the study of high-temperature, very reactive materials. It is an important method which provides access to the metastable state of an undercooled melt. In the absence of container walls, the nucleation rate is greatly reduced and undercooling up to (Tm-Tn)/Tm approx. equal to 0.2 can be obtained, where Tm and Tn are the melting and nucleation temperatures, respectively. Electromagnetic levitation represents a method particularly well-suited for the study of metallic melts. The TEMPUS (Tiegelfreies ElektroMagnetisches Prozessieren Unter Schwerelosgkeit) facility is a research instrument designed to perform electromagnetic levitation studies in reduced gravity. TEMPUS is a joint undertaking between DARA, the German Space Agency, and the Microgravity Science and Applications Division of NASA. The George C. Marshall Space Flight Center provides the leadership for scientific and management efforts which support the four US PI teams which performed experiments in the TEMPUS facility. The facility is sensitive to accelerations in the 1-10 Hz range. This became evident during the MSL-1 mission. Analysis of accelerometer and video data indicated that loss of sample control occurred during crew exercise periods which created disturbances in this frequency range. Prior to the MSL-1R flight the TEMPUS team, the accelerometer support groups and the mission operations team developed a strategy to provide for the operation of the facility without such disturbances. The successful implementation of this plan led to the highly successful operation of this facility during MSL-1R.

Upbend and M1 scissors mode in neutron-rich nuclei - consequences for r-process $$(n,\\gamma )$$ reaction rates

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

Larsen, A. C.; Goriely, S.; Bernstein, L. A.

2015-01-01

An enhanced probability for low-energy γ-emission ( upbend, Eγ < 3 MeV) at high excitation energies has been observed for several light and medium-mass nuclei close to the valley of stability. Also the M1 scissors mode seen in deformed nuclei increases the γ-decay probability for low-energy γ-rays (E γ ≈ 2–3 MeV). These phenomena, if present in neutron-rich nuclei, have the potential to increase radiative neutron-capture rates relevant for the r-process. Furthermore, the experimental and theoretical status of the upbend is discussed, and preliminary calculations of (n,γ) reaction rates for neutron-rich, mid-mass nuclei including the scissors mode are shown.

Fluoxetine Increases the Expression of miR-572 and miR-663a in Human Neuroblastoma Cell Lines.

PubMed

Mundalil Vasu, Mahesh; Anitha, Ayyappan; Takahashi, Taro; Thanseem, Ismail; Iwata, Keiko; Asakawa, Tetsuya; Suzuki, Katsuaki

2016-01-01

Evidence suggests neuroprotective effects of fluoxetine, a selective serotonin reuptake inhibitor (SSRI), on the developed neurons in the adult brain. In contrast, the drug may be deleterious to immature or undifferentiated neural cells, although the mechanism is unclear. Recent investigations have suggested that microRNAs (miRNA) may be critical for effectiveness of psychotropic drugs including SSRI. We investigated whether fluoxetine could modulate expressions of neurologically relevant miRNAs in two neuroblastoma SK-N-SH and SH-SY5Y cell lines. Initial screening results revealed that three (miR-489, miR-572 and miR-663a) and four (miR-320a, miR-489, miR-572 and miR-663a) miRNAs were up-regulated in SK-N-SH cells and SH-SY5Y cells, respectively, after 24 hours treatment of fluoxetine (1-25 μM). Cell viability was reduced according to the dose of fluoxetine. The upregulation of miR-572 and miR-663a was consistent in both the SH-SY5Y and SK-N-SH cells, confirmed by a larger scale culture condition. Our data is the first in vitro evidence that fluoxetine could increase the expression of miRNAs in undifferentiated neural cells, and that putative target genes of those miRNAs have been shown to be involved in fundamental neurodevelopmental processes.

PROPULSION AND POWER RAPID RESPONSE RESEARCH AND DEVELOPMENT (R&D) SUPPORT. Delivery Order 0011: Production Demonstration and Laboratory Evaluation of R-8 and R-8X Hydroprocessed Renewable Jet (HRJ) Fuel for the DoD Alternative Fuels Program

DTIC Science & Technology

2010-05-01

alternative fuel from halophyte (Salicornia oil from sea plants) was also produced by the Syntroleum Corporation and termed R- 8X. Syntroleum processed...these bio- oils without catalyst change-out or processing optimization. Only a portion of the fit for purpose and characterization testing was...jet fuel, up to 50 volume %, just as F-T SPK is allowed to be used in MIL-DTL-83133F. b) The R-8 feedstock of fats, oils , and grease (FOG) was

Frequency and Clinical Implication of the R450H Mutation in the Thyrotropin Receptor Gene in the Japanese Population Detected by Smart Amplification Process 2

PubMed Central

Yanagawa, Yoshimaro; Aoki, Tomoyuki; Morimura, Tadashi; Araki, Osamu; Kimura, Takao; Ogiwara, Takayuki; Kotajima, Nobuo; Yanagawa, Masumi; Murakami, Masami

2014-01-01

In Japanese pediatric patients with thyrotropin (TSH) resistance, the R450H mutation in TSH receptor gene (TSHR) is occasionally observed. We studied the frequency and clinical implication of the R450H mutation in TSHR in the general population of Japanese adults using smart amplification process 2 (SmartAmp2). We designed SmartAmp2 primer sets to detect this mutation using a drop of whole blood. We analyzed thyroid function, antithyroid antibodies, and this mutation in 429 Japanese participants who had not been found to have thyroid disease. Two cases without antithyroid antibodies were heterozygous for the R450H mutation in TSHR. Thus, the prevalence of this mutation was 0.47% in the general population and 0.63% among those without antithyroid antibodies. Their serum TSH concentrations were higher than the average TSH concentration not only in subjects without antithyroid antibodies but also in those with antithyroid antibodies. The R450H mutation in TSHR is relatively common in the Japanese population and potentially affects thyroid function. The present study demonstrates that the SmartAmp2 method is useful to detect the R450H mutation in TSHR, which is one of the common causes of TSH resistance in the Japanese population. PMID:24895636

Genome-Wide Identification of R2R3-MYB Genes and Expression Analyses During Abiotic Stress in Gossypium raimondii

PubMed Central

He, Qiuling; Jones, Don C.; Li, Wei; Xie, Fuliang; Ma, Jun; Sun, Runrun; Wang, Qinglian; Zhu, Shuijin; Zhang, Baohong

2016-01-01

The R2R3-MYB is one of the largest families of transcription factors, which have been implicated in multiple biological processes. There is great diversity in the number of R2R3-MYB genes in different plants. However, there is no report on genome-wide characterization of this gene family in cotton. In the present study, a total of 205 putative R2R3-MYB genes were identified in cotton D genome (Gossypium raimondii), that are much larger than that found in other cash crops with fully sequenced genomes. These GrMYBs were classified into 13 groups with the R2R3-MYB genes from Arabidopsis and rice. The amino acid motifs and phylogenetic tree were predicted and analyzed. The sequences of GrMYBs were distributed across 13 chromosomes at various densities. The results showed that the expansion of the G. Raimondii R2R3-MYB family was mainly attributable to whole genome duplication and segmental duplication. Moreover, the expression pattern of 52 selected GrMYBs and 46 GaMYBs were tested in roots and leaves under different abiotic stress conditions. The results revealed that the MYB genes in cotton were differentially expressed under salt and drought stress treatment. Our results will be useful for determining the precise role of the MYB genes during stress responses with crop improvement. PMID:27009386

Process for functionalizing alkanes

DOEpatents

Bergman, R.G.; Janowicz, A.H.; Periana, R.A.

1988-05-24

Process for functionalizing saturated hydrocarbons comprises: (a) reacting said saturated hydrocarbons of the formula: R[sub 1]H wherein H represents a hydrogen atom; and R[sub 1] represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRh[P(R[sub 2])[sub 3

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members assist as a crane lifts the Advanced Base Line Imager, the primary optical instrument, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

GOES-R Advanced Base Line Imager Installation

NASA Image and Video Library

2016-08-30

Team members assist as a crane moves the Advanced Base Line Imager, the primary optical instruments, for installation on the Geostationary Operational Environmental Satellite (GOES-R) inside the Astrotech payload processing facility in Titusville, Florida near NASA’s Kennedy Space Center. GOES-R will be the first satellite in a series of next-generation NOAA GOES Satellites. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

SWATH2stats: An R/Bioconductor Package to Process and Convert Quantitative SWATH-MS Proteomics Data for Downstream Analysis Tools.

PubMed

Blattmann, Peter; Heusel, Moritz; Aebersold, Ruedi

2016-01-01

SWATH-MS is an acquisition and analysis technique of targeted proteomics that enables measuring several thousand proteins with high reproducibility and accuracy across many samples. OpenSWATH is popular open-source software for peptide identification and quantification from SWATH-MS data. For downstream statistical and quantitative analysis there exist different tools such as MSstats, mapDIA and aLFQ. However, the transfer of data from OpenSWATH to the downstream statistical tools is currently technically challenging. Here we introduce the R/Bioconductor package SWATH2stats, which allows convenient processing of the data into a format directly readable by the downstream analysis tools. In addition, SWATH2stats allows annotation, analyzing the variation and the reproducibility of the measurements, FDR estimation, and advanced filtering before submitting the processed data to downstream tools. These functionalities are important to quickly analyze the quality of the SWATH-MS data. Hence, SWATH2stats is a new open-source tool that summarizes several practical functionalities for analyzing, processing, and converting SWATH-MS data and thus facilitates the efficient analysis of large-scale SWATH/DIA datasets.

Production of R,R-2,3-butanediol of ultra-high optical purity from Paenibacillus polymyxa ZJ-9 using homologous recombination.

PubMed

Zhang, Li; Cao, Can; Jiang, Ruifan; Xu, Hong; Xue, Feng; Huang, Weiwei; Ni, Hao; Gao, Jian

2018-08-01

The present study describes the use of metabolic engineering to achieve the production of R,R-2,3-butanediol (R,R-2,3-BD) of ultra-high optical purity (>99.99%). To this end, the diacetyl reductase (DAR) gene (dud A) of Paenibacillus polymyxa ZJ-9 was knocked out via homologous recombination between the genome and the previously constructed targeting vector pRN5101-L'C in a process based on homologous single-crossover. PCR verification confirmed the successful isolation of the dud A gene disruption mutant P. polymyxa ZJ-9-△dud A. Moreover, fermentation results indicated that the optical purity of R,R-2,3-BD increased from about 98% to over 99.99%, with a titer of 21.62 g/L in Erlenmeyer flasks. The latter was further increased to 25.88 g/L by fed-batch fermentation in a 5-L bioreactor. Copyright © 2018 Elsevier Ltd. All rights reserved.

Alternative methods for C.R.A pipeline welding

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

Belloni, A.

1996-12-01

The application of the GTAW process for C.R.A. (Corrosion Resistant Alloy) linepipe welding is a well known practice, nevertheless the high construction costs associated to the use of this process particularly for root pass welding (low welding speed) necessitate consideration of an updated version of the GMAW process (higher welding speed) for the same application. The present paper describes the progress obtained in using alternative welding methods to GTAW Cold wire such as: GTAW hot wire and GMAW to increase the welding speed and consequently reduce the overall project cost. The authors feel that this approach is essential to increasemore » the pipelaying productivity of a C.R.A. linepipe materials, at present still too far from that of the Carbon steel one.« less

A novel RNase G mutant that is defective in degradation of adhE mRNA but proficient in the processing of 16S rRNA precursor.

PubMed

Wachi, M; Kaga, N; Umitsuki, G; Clark, D P; Nagai, K

2001-12-21

Escherichia coli RNase G, encoded by the rng gene, is involved in both the processing of 16S rRNA precursor and the degradation of adhE mRNA. Consequently, defects in RNase G result in elevation of AdhE levels. Furthermore, the adhR430 mutant strain, DC430, is reported to overproduce the AdhE protein in a manner dependent on the adhC81 mutation. We found that overproduction of AdhE by DC430 was reversed to wild-type levels by introduction of a plasmid carrying the wild-type allele of rng. Mapping by P1-phage-mediated transduction also indicated that a mutation involved in AdhE overproduction was located around the rng region in DC430. DNA sequencing of the rng region revealed that DC430 indeed had a mutation in the rng gene: a G1022 to A transition that caused substitution of Gly341 with Ser and which was named rng430. This lies in the highly conserved region of the RNase E/RNase G family, called high similarity region 2 (HSR2). However, very interestingly, rng430 mutant strains did not accumulate the 16.3S precursor of 16S rRNA unlike rng::cat mutants. We also found that the Rng1 mutant protein, which is truncated in its C-terminal domain encompassing HSR2, exhibited a residual processing activity against the 16S rRNA precursor, when overproduced. These results indicate that the HSR2 of RNase G plays an important role in substrate recognition and/or ribonucleolytic action.

Nutrient fluxes at the landscape level and the R* rule

USGS Publications Warehouse

Ju, Shu; DeAngelis, Donald L.

2010-01-01

Nutrient cycling in terrestrial ecosystems involves not only the vertical recycling of nutrients at specific locations in space, but also biologically driven horizontal fluxes between different areas of the landscape. This latter process can result in net accumulation of nutrients in some places and net losses in others. We examined the effects of such nutrient-concentrating fluxes on the R* rule, which predicts that the species that can survive in steady state at the lowest level of limiting resource, R*, can exclude all competing species. To study the R* rule in this context, we used a literature model of plant growth and nutrient cycling in which both nutrients and light may limit growth, with plants allocating carbon and nutrients between foliage and roots according to different strategies. We incorporated the assumption that biological processes may concentrate nutrients in some parts of the landscape. We assumed further that these processes draw nutrients from outside the zone of local recycling at a rate proportional to the local biomass density. Analysis showed that at sites where there is a sufficient biomass-dependent accumulation of nutrients, the plant species with the highest biomass production rates (roughly corresponding to the best competitors) do not reduce locally available nutrients to a minimum concentration level (that is, minimum R*), as expected from the R* rule, but instead maximize local nutrient concentration. These new results require broadening of our understanding of the relationships between nutrients and vegetation competition on the landscape level. The R* rule is replaced by a more complex criterion that varies across a landscape and reduces to the R* rule only under certain limiting conditions.

Research in Stochastic Processes.

DTIC Science & Technology

1983-10-01

increases. A more detailed investigation for the exceedances themselves (rather than Just the cluster centers) was undertaken, together with J. HUsler and...J. HUsler and M.R. Leadbetter, Compoung Poisson limit theorems for high level exceedances by stationary sequences, Center for Stochastic Processes...stability by a random linear operator. C.D. Hardin, General (asymmetric) stable variables and processes. T. Hsing, J. HUsler and M.R. Leadbetter, Compound

Site-preference and valency for rare-earth sites in (R-Ce)2Fe14B [R =La,Nd] magnets

NASA Astrophysics Data System (ADS)

Alam, Aftab; Khan, Mahmud; McCallum, R. W.; Johnson, D. D.

2013-03-01

Rare-earth (R) permanent magnets of R2Fe14B have technological importance due to their high energy products, and they have two symmetry distinct R-sites (Wyckoff 4f and 4g) that affect chemistry and valence. Designing magnetic behavior and stability via alloying is technologically relevant to reduce critical (expensive) R-content while retaining key properties; cerium, an abundant (cheap) R-element, offers this potential. We calculate magnetic properties and Ce site preference in (R1-xCex)Fe14B [R=La,Nd] using density functional theory (DFT) methods. The Fe moments compare well with neutron scattering data - remain weakly affected by Hubbard U, but improved with spin-orbit coupling. In (La,Ce)2Fe14B, Ce alloys for 0 < x < 1 with a preference for smaller R(4f) sites, as observed, a trend we find unaffected by valence. Whereas in (Nd,Ce)2Fe14B, Ce is predicted to have limited alloying (x < 0.3) with a preference for larger R(4g) sites, resulting in weak partial ordering and segregation. Curie temperatures versus x were predicted for a typical sample processing and verified experimentally. We shall also present some initial results on the critical mixed valency of Ce in related compounds. Work at Ames Laboratory was supported by the U.S. Department of Energy, ARPA-E under the REACT program (0472-1526)

Reactivation of epigenetically silenced miR-512 and miR-373 sensitizes lung cancer cells to cisplatin and restricts tumor growth

PubMed Central

Adi Harel, S; Bossel Ben-Moshe, N; Aylon, Y; Bublik, D R; Moskovits, N; Toperoff, G; Azaiza, D; Biagoni, F; Fuchs, G; Wilder, S; Hellman, A; Blandino, G; Domany, E; Oren, M

2015-01-01

MicroRNAs (miRs) regulate a variety of cellular processes, and their impaired expression is involved in cancer. Silencing of tumor-suppressive miRs in cancer can occur through epigenetic modifications, including DNA methylation and histone deacetylation. We performed comparative miR profiling on cultured lung cancer cells before and after treatment with 5′aza-deoxycytidine plus Trichostatin A to reverse DNA methylation and histone deacetylation, respectively. Several tens of miRs were strongly induced by such ‘epigenetic therapy'. Two representatives, miR-512-5p (miR-512) and miR-373, were selected for further analysis. Both miRs were secreted in exosomes. Re-expression of both miRs augmented cisplatin-induced apoptosis and inhibited cell migration; miR-512 also reduced cell proliferation. TEAD4 mRNA was confirmed as a direct target of miR-512; likewise, miR-373 was found to target RelA and PIK3CA mRNA directly. Our results imply that miR-512 and miR-373 exert cell-autonomous and non-autonomous tumor-suppressive effects in lung cancer cells, where their re-expression may benefit epigenetic cancer therapy. PMID:25591738

A Model Sea Urchin Spicule Matrix Protein, rSpSM50, Is a Hydrogelator That Modifies and Organizes the Mineralization Process.

PubMed

Jain, Gaurav; Pendola, Martin; Huang, Yu-Chieh; Gebauer, Denis; Evans, John Spencer

2017-05-30

In the purple sea urchin Strongylocentrotus purpuratus, the formation and mineralization of fracture-resistant skeletal elements such as the embryonic spicule require the combinatorial participation of numerous spicule matrix proteins such as SpSM50. However, because of its limited abundance and solubility issues, it has been difficult to pursue extensive in vitro biochemical studies of SpSM50 protein and deduce its role in spicule formation and mineralization. To circumvent these problems, we expressed a tag-free bacterial model recombinant spicule matrix protein, rSpSM50. Bioinformatics and biophysical experiments confirm that rSpSM50 is an intrinsically disordered, aggregation-prone C-type lectin-like domain-containing protein that forms dimensionally and internally heterogeneous protein hydrogels that control the in vitro mineralization process in three ways. The hydrogels (1) kinetically stabilize the aqueous calcium carbonate system against nucleation and thermodynamically destabilize the initially formed ACC in bulk solution, (2) promote and organize faceted single-crystal calcite and polycrystalline vaterite nanoparticles, and (3) promote surface texturing of calcite crystals and induce subsurface nanoporosities and channels within both calcite and vaterite crystals. Many of these features are also common to mollusk shell nacre proteins and the sea urchin spicule matrix glycoprotein, SpSM30B/C, and we conclude that rSpSM50 is a spiculogenesis hydrogelator protein that exhibits traits found in other calcium carbonate mineral-modification proteins.

An R-matrix study of electron induced processes in BF3 plasma

NASA Astrophysics Data System (ADS)

Gupta, Dhanoj; Chakrabarti, Kalyan; Yoon, Jung-Sik; Song, Mi-Young

2017-12-01

An R-matrix formalism is used to study electron collision with the BF3 molecule using Quantemol-N, a computational system for electron molecule collisions which uses the molecular R-matrix method. Several target models are tested for BF3 in its equilibrium geometry, and the results are presented for the best model. Scattering calculations are then performed to yield resonance parameters, elastic, differential, excitation, and momentum transfer cross sections. The results for all the cross sections are compared with the experimental and theoretical data, and a good agreement is obtained. The resonances have been detected at 3.79 and 13.58 eV, with the ionization threshold being 15.7 eV. We have also estimated the absolute dissociative electron attachment (DEA) cross section for the F- ion production from BF3, which is a maiden attempt. The peak of the DEA is at around 13.5 eV, which is well supported by the resonance detected at 13.58 eV. The cross sections reported here find a variety of applications in the plasma technology.

Methionine Regulates mTORC1 via the T1R1/T1R3-PLCβ-Ca2+-ERK1/2 Signal Transduction Process in C2C12 Cells.

PubMed

Zhou, Yuanfei; Ren, Jiao; Song, Tongxing; Peng, Jian; Wei, Hongkui

2016-10-11

The mammalian target of rapamycin complex 1 (mTORC1) integrates amino acid (AA) availability to support protein synthesis and cell growth. Taste receptor type 1 member (T1R) is a G protein-coupled receptor that functions as a direct sensor of extracellular AA availability to regulate mTORC1 through Ca 2+ stimulation and extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation. However, the roles of specific AAs in T1R1/T1R3-regulated mTORC1 are poorly defined. In this study, T1R1 and T1R3 subunits were expressed in C2C12 myotubes, and l-AA sensing was accomplished by T1R1/T1R3 to activate mTORC1. In response to l-AAs, such as serine (Ser), arginine (Arg), threonine (Thr), alanine (Ala), methionine (Met), glutamine (Gln), and glycine (Gly), Met induced mTORC1 activation and promoted protein synthesis. Met also regulated mTORC1 via T1R1/T1R3-PLCβ-Ca 2+ -ERK1/2 signal transduction. Results revealed a new role for Met-regulated mTORC1 via an AA receptor. Further studies should be performed to determine the role of T1R1/T1R3 in mediating extracellular AA to regulate mTOR signaling and to reveal its mechanism.

Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31, Revision 1

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

S.G.McLin; W.J. Stone

2004-06-01

Hydrologic information is essential for environmental efforts at Los Alamos National Laboratory. Testing at new characterization wells being drilled to the regional aquifer (''R wells'') to improve the conceptual hydrogeologic model of the Pajarito Plateau is providing such information. Field tests were conducted on various zones of saturation penetrated by the R wells to collect data needed for determining hydraulic properties. This document provides details of the design and execution of testing as well as an analysis of data for five new wells: R-9i, R-13, R-19, R-22, and R-31. One well (R-13) was evaluated by a pumping test and themore » rest (R-9i, R-19, R-22, and R-31) were evaluated by injection tests. Characterization well R-9i is located in Los Alamos Canyon approximately 0.3 mi west of the Route 4/Route 502 intersection. It was completed at a depth of 322 ft below ground surface (bgs) in March 2000. This well was constructed with two screens positioned below the regional water table. Both screens were tested. Screen 1 is completed at about 189-200 ft bgs in fractured basalt, and screen 2 is completed at about 270-280 ft bgs in massive basalt. Specific capacity analysis of the screen 1 data suggests that the fractured basalt has a transmissivity (T) of 589 ft{sup 2}/day and corresponds to a hydraulic conductivity (K) of 7.1 ft/day based on a saturated thickness of 83 ft. The injection test data from the massive basalt near screen 2 were analyzed by the Bouwer-Rice slug test methodology and suggest that K is 0.11 ft/day, corresponding to a T of about 2.8 ft{sup 2}/day based on a saturated thickness of 25 ft. Characterization well R-13 is located in Mortandad Canyon just west of the eastern Laboratory boundary. It was completed at a depth of 1029 ft bgs in February 2002. This well was constructed with one 60-ft long screen positioned about 125 ft below the regional water table. This screen is completed at about 958-1019 ft bgs and straddles the geologic

BCoR-L1 variation and breast cancer.

PubMed

Lose, Felicity; Arnold, Jeremy; Young, David B; Brown, Carolyn J; Mann, Graham J; Pupo, Gulietta M; Khanna, Kum Kum; Chenevix-Trench, Georgia; Spurdle, Amanda B

2007-01-01

BRCA1 is involved in numerous essential processes in the cell, and the effects of BRCA1 dysfunction in breast cancer carcinogenesis are well described. Many of the breast cancer susceptibility genes such as BRCA2, p53, ATM, CHEK2, and BRIP1 encode proteins that interact with BRCA1. BCL6 corepressor-like 1 (BCoR-L1) is a newly described BRCA1-interacting protein that displays high homology to several proteins known to be involved in the fundamental processes of DNA damage repair and transcription regulation. BCoR-L1 has been shown to play a role in transcription corepression, and expression of the X-linked BCoR-L1 gene has been reported to be dysregulated in breast cancer subjects. BCoR-L1 is located on the X chromosome and is subject to X inactivation. We performed mutation analysis of 38 BRCA1/2 mutation-negative breast cancer families with male breast cancer, prostate cancer, and/or haplotype sharing around BCoR-L1 to determine whether there is a role for BCoR-L1 as a high-risk breast cancer predisposition gene. In addition, we conducted quantitative real-time PCR (qRT-PCR) on lymphoblastoid cell lines (LCLs) from the index cases from these families and a number of cancer cell lines to assess the role of BCoR-L1 dysregulation in cancer and cancer families. Very little variation was detected in the coding region, and qRT-PCR analysis revealed that BCoR-L1 expression is highly variable in cancer-free subjects, high-risk breast cancer patients, and cancer cell lines. We also report the investigation of a new expression control, DIDO1 (death inducer-obliterator 1), that is superior to GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and UBC (ubiquitin C) for analysis of expression in LCLs. Our results suggest that BCoR-L1 expression does not play a large role in predisposition to familial breast cancer.

MitomiRs in human inflamm-aging: a hypothesis involving miR-181a, miR-34a and miR-146a.

PubMed

Rippo, Maria Rita; Olivieri, Fabiola; Monsurrò, Vladia; Prattichizzo, Francesco; Albertini, Maria Cristina; Procopio, Antonio Domenico

2014-08-01

Mitochondria are intimately involved in the aging process. The decline of autophagic clearance during aging affects the equilibrium between mitochondrial fusion and fission, leading to a build-up of dysfunctional mitochondria, oxidative stress, chronic low-grade inflammation, and increased apoptosis rates, the main hallmarks of aging. Current research suggests that a large number of microRNAs (miRs or miRNAs) are differentially expressed during cell aging. Other lines of evidence indicate that several miRs likely share in "inflamm-aging", an aging-related state characterized by systemic chronic inflammation that in turn provides a biological background favoring susceptibility to age-related diseases and disabilities. Interestingly, miRs can modulate mitochondrial activity, and a discrete miR set has recently been identified in mitochondria of different species and cell types (mitomiRs). Here we show that some mitomiRs (let7b, mir-146a, -133b, -106a, -19b, -20a, -34a, -181a and -221) are also among the miRs primarily involved in cell aging and in inflamm-aging. Of note, Ingenuity Pathway Analysis (IPA) of aging-related mitomiR targets has disclosed a number of resident mitochondrial proteins playing large roles in energy metabolism, mitochondrial transport and apoptosis. Among these, Bcl-2 family members--which are critically involved in maintaining mitochondrial integrity--may play a role in controlling mitochondrial function and dysfunction during cellular aging, also considering that Bcl-2, the master member of the family, is an anti-oxidant and anti-apoptotic factor and regulates mitochondrial fission/fusion and autophagy. This intriguing hypothesis is supported by several observations: i) in endothelial cells undergoing replicative senescence (HUVECs), a well-established model of cell senescence, miR-146a, miR-34a, and miR-181a are over-expressed whereas their target Bcl-2 is down-regulated; ii) IPA of the miR-146a, miR-34a and miR-181a network shows that they

Research in Stochastic Processes

DTIC Science & Technology

1988-10-10

To appear in Proceedings Volume, Oberwolfach Conf. on Extremal Value Theory, Ed. J. HUsler and R. Reiss, Springer. 4. M.R. Leadbetter. The exceedance...Hsing, J. Husler and M.R. Leadbetter, On the exceedance point process for a stationary sequence, Probability Theor. Rel. Fields, 20, 1988, 97-112 Z.J...Oberwotfach Conf. on Extreme Value Theory. J. Husler and R. Reiss. eds.. Springer. to appear V. Mandrekar, On a limit theorem and invariance

BSR: B-spline atomic R-matrix codes

NASA Astrophysics Data System (ADS)

Zatsarinny, Oleg

2006-02-01

BSR is a general program to calculate atomic continuum processes using the B-spline R-matrix method, including electron-atom and electron-ion scattering, and radiative processes such as bound-bound transitions, photoionization and polarizabilities. The calculations can be performed in LS-coupling or in an intermediate-coupling scheme by including terms of the Breit-Pauli Hamiltonian. New version program summaryTitle of program: BSR Catalogue identifier: ADWY Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWY Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computers on which the program has been tested: Microway Beowulf cluster; Compaq Beowulf cluster; DEC Alpha workstation; DELL PC Operating systems under which the new version has been tested: UNIX, Windows XP Programming language used: FORTRAN 95 Memory required to execute with typical data: Typically 256-512 Mwords. Since all the principal dimensions are allocatable, the available memory defines the maximum complexity of the problem No. of bits in a word: 8 No. of processors used: 1 Has the code been vectorized or parallelized?: no No. of lines in distributed program, including test data, etc.: 69 943 No. of bytes in distributed program, including test data, etc.: 746 450 Peripherals used: scratch disk store; permanent disk store Distribution format: tar.gz Nature of physical problem: This program uses the R-matrix method to calculate electron-atom and electron-ion collision processes, with options to calculate radiative data, photoionization, etc. The calculations can be performed in LS-coupling or in an intermediate-coupling scheme, with options to include Breit-Pauli terms in the Hamiltonian. Method of solution: The R-matrix method is used [P.G. Burke, K.A. Berrington, Atomic and Molecular Processes: An R-Matrix Approach, IOP Publishing, Bristol, 1993; P.G. Burke, W.D. Robb, Adv. At. Mol. Phys. 11 (1975) 143; K.A. Berrington, W.B. Eissner, P.H. Norrington, Comput

Micro-RNA Profiling in Human Serum Reveals Compartment-Specific Roles of miR-571 and miR-652 in Liver Cirrhosis

PubMed Central

Roderburg, Christoph; Mollnow, Tobias; Bongaerts, Brenda; Elfimova, Natalia; Vargas Cardenas, David; Berger, Katharina; Zimmermann, Henning; Koch, Alexander; Vucur, Mihael; Luedde, Mark; Hellerbrand, Claus; Odenthal, Margarete; Trautwein, Christian; Tacke, Frank; Luedde, Tom

2012-01-01

Background and Aims Micro-RNAs (miRNAs) have recently emerged as crucial modulators of molecular processes involved in chronic liver diseases. The few miRNAs with previously proposed roles in liver cirrhosis were identified in screening approaches on liver parenchyma, mostly in rodent models. Therefore, in the present study we performed a systematic screening approach in order to identify miRNAs with altered levels in the serum of patients with chronic liver disease and liver cirrhosis. Methods We performed a systematic, array-based miRNA expression analysis on serum samples from patients with liver cirrhosis. In functional experiments we evaluated the relationship between alterations of miRNA serum levels and their role in distinct cellular compartments involved in hepatic cirrhosis. Results The array analysis and the subsequent confirmation by qPCR in a larger patient cohort identified significant alterations in serum levels of miR-513-3p, miR-571 and miR-652, three previously uncharacterized miRNAs, in patients with alcoholic or hepatitis C induced liver cirrhosis. Of these, miR-571 serum levels closely correlated with disease stages, thus revealing potential as a novel biomarker for hepatic cirrhosis. Further analysis revealed that up-regulation of miR-571 in serum reflected a concordant regulation in cirrhotic liver tissue. In isolated primary human liver cells, miR-571 was up-regulated in human hepatocytes and hepatic stellate cells in response to the pro-fibrogenic cytokine TGF-β. In contrast, alterations in serum levels of miR-652 were stage-independent, reflecting a concordant down-regulation of this miRNA in circulating monocytes of patients with liver cirrhosis, which was inducible by proinflammatory stimuli like bacterial lipopolysaccharide. Conclusion Alterations of miR571 and miR-652 serum levels in patients with chronic liver disease reflect their putative roles in the mediation of fibrogenic and inflammatory processes in distinct cellular

OncomiR Addiction Is Generated by a miR-155 Feedback Loop in Theileria-Transformed Leukocytes

PubMed Central

Medjkane, Souhila; Perichon, Martine; Yin, Qinyan; Flemington, Erik; Weitzman, Matthew D.; Weitzman, Jonathan B.

2013-01-01

The intracellular parasite Theileria is the only eukaryote known to transform its mammalian host cells. We investigated the host mechanisms involved in parasite-induced transformation phenotypes. Tumour progression is a multistep process, yet ‘oncogene addiction’ implies that cancer cell growth and survival can be impaired by inactivating a single gene, offering a rationale for targeted molecular therapies. Furthermore, feedback loops often act as key regulatory hubs in tumorigenesis. We searched for microRNAs involved in addiction to regulatory loops in leukocytes infected with Theileria parasites. We show that Theileria transformation involves induction of the host bovine oncomiR miR-155, via the c-Jun transcription factor and AP-1 activity. We identified a novel miR-155 target, DET1, an evolutionarily-conserved factor involved in c-Jun ubiquitination. We show that miR-155 expression led to repression of DET1 protein, causing stabilization of c-Jun and driving the promoter activity of the BIC transcript containing miR-155. This positive feedback loop is critical to maintain the growth and survival of Theileria-infected leukocytes; transformation is reversed by inhibiting AP-1 activity or miR-155 expression. This is the first demonstration that Theileria parasites induce the expression of host non-coding RNAs and highlights the importance of a novel feedback loop in maintaining the proliferative phenotypes induced upon parasite infection. Hence, parasite infection drives epigenetic rewiring of the regulatory circuitry of host leukocytes, placing miR-155 at the crossroads between infection, regulatory circuits and transformation. PMID:23637592

Parallel determination of gut permeability in man with M(r) 400, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol.

PubMed

Parlesak, A; Bode, J C; Bode, C

1994-11-01

Polyethylene glycol has been in use for a number of years for the assessment of gut permeability. The methods so far employed are usually limited to polyethylene glycols in the low relative molecular mass range (up to M(r) 1300). We developed a method for the simultaneous determination of gut permeability to M(r) 400, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol, by applying a single oral dose of an appropriate mixture of these polyethylene glycols. After extraction from 24 h-urine, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol were quantified by size exclusion chromatography, while M(r) 400 polyethylene glycol was determined by reversed phase chromatography. The detection limit of polyethylene glycol in the relative molecular mass range between M(r) 1500 and M(r) 10,000 was found to be 0.2 mg/l urine, and the detection limit of M(r) 400 polyethylene glycol 5 mg/l urine. Recovery of the polyethylene glycols (N = 6) were 86.6% (CV: 4.8%) for M(r) 400, 94.1% (CV: 7.2%) for M(r) 1500, 97.1% (CV: 5.5%) for M(r) 4000 and 97.4% (CV: 5.6%) for M(r) 10,000. No significant difference was found between the excretion rates in 24 h-urine of M(r) 400 and M(r) 1500 polyethylene glycols in patients with Crohn's disease (M(r) 400: 34.4 +/- 5.5%; M(r) 1500: 5.22 +/- 2.27%; mean +/- SEM, N = 10) and healthy controls (M(r) 400: 33.6 +/- 3.2%, M(r) 1500: 1.09 +/- 0.26%; N = 21). The excretion rate of M(r) 4000 polyethylene glycol was markedly higher in patients with Crohn's disease (0.462 +/- 0.177%) than in healthy controls (0.049 +/- 0.012%, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Point Processes.

DTIC Science & Technology

1987-05-01

O and N(B) < - a.s. for each BEMA. (ii) N(U Bn) = N(Bn) a.s. for any disjoint BI.B 2 .. in ’ R . n n The random variable N(A) represents the number...P(N’(B) = 0). B E o . (C) If (v.X1 X2 ....) (v.Xi.X .. ). then N d N’. The converse is true when E = R + or R and the X ’s are the ordered T ’s.+ n n... R + that are continuous and such that (x: f(x)> O ) is a bounded set. Theorem 1.4. Suppose N and N’ are point processes on E. The following statements

Federal R&D Funding: Trends and Projections

NASA Astrophysics Data System (ADS)

White, K. S.

2014-12-01

Between sequestration, shutdowns, and budget "cliffs," the federal budget process has experienced many challenges in recent years. Budgets for research and development (R&D) have mirrored these larger fiscal constraints. Over the past decade, many agencies and programs have seen flat or declining budgets, particularly when inflation is considered. This talk will examine recent geoscience R&D funding in the historical context and examine projections of future science funding in the framework of the Budget Control Act and other initiatives.

Psychometric evaluation of the Swedish adaptation of the Inventory for Assessing the Process of Cultural Competence Among Healthcare Professionals--Revised (IAPCC-R).

PubMed

Olt, Helen; Jirwe, Maria; Gustavsson, Petter; Emami, Azita

2010-01-01

The purpose of this study was to describe the translation, adaption, and psychometric evaluation process in relation to validity and reliability of the Swedish version of the instrument, Inventory for Assessing The Process of Cultural Competence Among Healthcare Professionals-Revised (IAPCC-R) following the translation, adaptation, and psychometric evaluation process. Validity tests were conducted on the response processes (N = 15), the content (N = 7), and the internal structure of the instrument (N = 334). Reliability (alpha = .65 for the total scale varying between -.01 and .65 for the different subscales) was evaluated in terms of internal consistency. Results indicated weak validity and reliability though it is difficult to conclude whether this is related to adaptation issues or the original construction.The testing of the response process identified problems in relation to respondents' conceptualization of cultural competence. The test of the content identified a weak correspondence between the items and the underlying model. In addition, a confirmatory factor analysis did not confirm the proposed structure of the instrument. This study concludes that this instrument is not valid and reliable for use with a Swedish population of practicing nurses or nursing students.

GOES-R Arrival and Offload

NASA Image and Video Library

2016-08-22

An Air Force C-5 Galaxy transport plane approaches the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida to deliver the GOES-R spacecraft for launch processing. The GOES series are weather satellites operated by NOAA to enhance forecasts. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

Evaluating firms' R&D performance using best worst method.

PubMed

Salimi, Negin; Rezaei, Jafar

2018-02-01

Since research and development (R&D) is the most critical determinant of the productivity, growth and competitive advantage of firms, measuring R&D performance has become the core of attention of R&D managers, and an extensive body of literature has examined and identified different R&D measurements and determinants of R&D performance. However, measuring R&D performance and assigning the same level of importance to different R&D measures, which is the common approach in existing studies, can oversimplify the R&D measuring process, which may result in misinterpretation of the performance and consequently fallacy R&D strategies. The aim of this study is to measure R&D performance taking into account the different levels of importance of R&D measures, using a multi-criteria decision-making method called Best Worst Method (BWM) to identify the weights (importance) of R&D measures and measure the R&D performance of 50 high-tech SMEs in the Netherlands using the data gathered in a survey among SMEs and from R&D experts. The results show how assigning different weights to different R&D measures (in contrast to simple mean) results in a different ranking of the firms and allow R&D managers to formulate more effective strategies to improve their firm's R&D performance by applying knowledge regarding the importance of different R&D measures. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Brain Imaging and rTMS Studies of Individual Differences in Cognitive Processing

DTIC Science & Technology

2013-08-09

Institution: Address: Phone: Fax: Email : Web Page: Contract: Project Title: Program Officer: Dr. Marcel Adam Just Carnegie Mellon University...and multitasking ) are included in the progress report using well established sets of materials. In the sentence and discourse tasks, participants...compensatory partnerships and the re-emergence of the primary regions. 3. Cortical reorganization induced by rTMS during multitasking (listening to

SOT1, a pentatricopeptide repeat protein with a small MutS-related domain, is required for correct processing of plastid 23S-4.5S rRNA precursors in Arabidopsis thaliana.

PubMed

Wu, Wenjuan; Liu, Sheng; Ruwe, Hannes; Zhang, Delin; Melonek, Joanna; Zhu, Yajuan; Hu, Xupeng; Gusewski, Sandra; Yin, Ping; Small, Ian D; Howell, Katharine A; Huang, Jirong

2016-03-01

Ribosomal RNA processing is essential for plastid ribosome biogenesis, but is still poorly understood in higher plants. Here, we show that SUPPRESSOR OF THYLAKOID FORMATION1 (SOT1), a plastid-localized pentatricopeptide repeat (PPR) protein with a small MutS-related domain, is required for maturation of the 23S-4.5S rRNA dicistron. Loss of SOT1 function leads to slower chloroplast development, suppression of leaf variegation, and abnormal 23S and 4.5S processing. Predictions based on the PPR motif sequences identified the 5' end of the 23S-4.5S rRNA dicistronic precursor as a putative SOT1 binding site. This was confirmed by electrophoretic mobility shift assay, and by loss of the abundant small RNA 'footprint' associated with this site in sot1 mutants. We found that more than half of the 23S-4.5S rRNA dicistrons in sot1 mutants contain eroded and/or unprocessed 5' and 3' ends, and that the endonucleolytic cleavage product normally released from the 5' end of the precursor is absent in a sot1 null mutant. We postulate that SOT1 binding protects the 5' extremity of the 23S-4.5S rRNA dicistron from exonucleolytic attack, and favours formation of the RNA structure that allows endonucleolytic processing of its 5' and 3' ends. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

The Eucalyptus grandis R2R3-MYB transcription factor family: evidence for woody growth-related evolution and function.

PubMed

Soler, Marçal; Camargo, Eduardo Leal Oliveira; Carocha, Victor; Cassan-Wang, Hua; San Clemente, Hélène; Savelli, Bruno; Hefer, Charles A; Paiva, Jorge A Pinto; Myburg, Alexander A; Grima-Pettenati, Jacqueline

2015-06-01

The R2R3-MYB family, one of the largest transcription factor families in higher plants, controls a wide variety of plant-specific processes including, notably, phenylpropanoid metabolism and secondary cell wall formation. We performed a genome-wide analysis of this superfamily in Eucalyptus, one of the most planted hardwood trees world-wide. A total of 141 predicted R2R3-MYB sequences identified in the Eucalyptus grandis genome sequence were subjected to comparative phylogenetic analyses with Arabidopsis thaliana, Oryza sativa, Populus trichocarpa and Vitis vinifera. We analysed features such as gene structure, conserved motifs and genome location. Transcript abundance patterns were assessed by RNAseq and validated by high-throughput quantitative PCR. We found some R2R3-MYB subgroups with expanded membership in E. grandis, V. vinifera and P. trichocarpa, and others preferentially found in woody species, suggesting diversification of specific functions in woody plants. By contrast, subgroups containing key genes regulating lignin biosynthesis and secondary cell wall formation are more conserved across all of the species analysed. In Eucalyptus, R2R3-MYB tandem gene duplications seem to disproportionately affect woody-preferential and woody-expanded subgroups. Interestingly, some of the genes belonging to woody-preferential subgroups show higher expression in the cambial region, suggesting a putative role in the regulation of secondary growth. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Large-scale evaluation of β -decay rates of r -process nuclei with the inclusion of first-forbidden transitions

NASA Astrophysics Data System (ADS)

Marketin, T.; Huther, L.; Martínez-Pinedo, G.

2016-02-01

Background: r -process nucleosynthesis models rely, by necessity, on nuclear structure models for input. Particularly important are β -decay half-lives of neutron-rich nuclei. At present only a single systematic calculation exists that provides values for all relevant nuclei making it difficult to test the sensitivity of nucleosynthesis models to this input. Additionally, even though there are indications that their contribution may be significant, the impact of first-forbidden transitions on decay rates has not been systematically studied within a consistent model. Purpose: Our goal is to provide a table of β -decay half-lives and β -delayed neutron emission probabilities, including first-forbidden transitions, calculated within a fully self-consistent microscopic theoretical framework. The results are used in an r -process nucleosynthesis calculation to asses the sensitivity of heavy element nucleosynthesis to weak interaction reaction rates. Method: We use a fully self-consistent covariant density functional theory (CDFT) framework. The ground state of all nuclei is calculated with the relativistic Hartree-Bogoliubov (RHB) model, and excited states are obtained within the proton-neutron relativistic quasiparticle random phase approximation (p n -RQRPA). Results: The β -decay half-lives, β -delayed neutron emission probabilities, and the average number of emitted neutrons have been calculated for 5409 nuclei in the neutron-rich region of the nuclear chart. We observe a significant contribution of the first-forbidden transitions to the total decay rate in nuclei far from the valley of stability. The experimental half-lives are in general well reproduced for even-even, odd-A , and odd-odd nuclei, in particular for short-lived nuclei. The resulting data table is included with the article as Supplemental Material. Conclusions: In certain regions of the nuclear chart, first-forbidden transitions constitute a large fraction of the total decay rate and must be

The Dorsolateral Prefrontal Cortex Plays a Role in Self-Initiated Elaborative Cognitive Processing during Episodic Memory Encoding: rTMS Evidence

PubMed Central

Hawco, Colin; Berlim, Marcelo T.; Lepage, Martin

2013-01-01

During episodic memory encoding, elaborative cognitive processing can improve later recall or recognition. While multiple studies examined the neural correlates of encoding strategies, few studies have explicitly focused on the self-initiation of elaborative encoding. Repetitive transcranial magnetic stimulation (rTMS), a method which can transiently disrupt neural activity, was administered during an associative encoding task. rTMS was either applied to the left dorsolateral prefrontal cortex (DLPFC) or to the vertex (a control region not involved in memory encoding) during presentation of pairs of words. Pairs could be semantically related or not related. Two encoding instructions were given, either cueing participants to analyze semantic relationships (cued condition), or to memorize the pair without any specific strategy cues (the self-initiated condition). Participants filled out a questionnaire regarding their use of memory strategies and performed a cued-recall task. We hypothesized that if the DLPFC plays a role in the self-initiation of elaborative encoding we would observe a reduction in memory performance in the self-initiated condition, particularly for related. We found a significant correlation between the effects of rTMS and strategy use, only in the self-initiated condition with related pairs. High strategy users showed reduced performance following DLPFC stimulation, while low strategy users tended to show increased recall following DLPFC stimulation during encoding. These results suggest the left DLPFC may be involved in the self-initiation of memory strategy use, and individuals may utilize different neural networks depending on their use of encoding strategies. PMID:24040072

Classification of galaxy type from images using Microsoft R Server

NASA Astrophysics Data System (ADS)

de Vries, Andrie

2017-06-01

Many astronomers working in the field of AstroInformatics write code as part of their work. Although the programming language of choice is Python, a small number (8%) use R. R has its specific strengths in the domain of statistics, and is often viewed as limited in the size of data it can handle. However, Microsoft R Server is a product that removes these limitations by being able to process much larger amounts of data. I present some highlights of R Server, by illustrating how to fit a convolutional neural network using R. The specific task is to classify galaxies, using only images extracted from the Sloan Digital Skyserver.

Cold-Worked Inconel(R) 718 Bars

NASA Technical Reports Server (NTRS)

Montano, J. W.

1988-01-01

Cold working and double aging yield high strength without sacrifice of resistance to corrosion. Report presents data on mechanical properties and stress-corrosion resistance of triple-melted, solution-treated, work-strengthened, direct-double-aged Inconel(R) 718 alloy. Triple melting consists of vacuum induction melting, electro-slag remelting, and vacuum arm remelting. Data indicate advance in processing of large-diameter bars. New process increases yield strength without reducing the elongation, reduction of area, and grain size.

EVALUATING REGIONAL PREDICTIVE CAPACITY OF A PROCESS-BASED MERCURY EXPOSURE MODEL, REGIONAL-MERCURY CYCLING MODEL (R-MCM), APPLIED TO 91 VERMONT AND NEW HAMPSHIRE LAKES AND PONDS, USA

EPA Science Inventory

Regulatory agencies must develop fish consumption advisories for many lakes and rivers with limited resources. Process-based mathematical models are potentially valuable tools for developing regional fish advisories. The Regional Mercury Cycling model (R-MCM) was specifically d...

SpidermiR: An R/Bioconductor Package for Integrative Analysis with miRNA Data.

PubMed

Cava, Claudia; Colaprico, Antonio; Bertoli, Gloria; Graudenzi, Alex; Silva, Tiago C; Olsen, Catharina; Noushmehr, Houtan; Bontempi, Gianluca; Mauri, Giancarlo; Castiglioni, Isabella

2017-01-27

Gene Regulatory Networks (GRNs) control many biological systems, but how such network coordination is shaped is still unknown. GRNs can be subdivided into basic connections that describe how the network members interact e.g., co-expression, physical interaction, co-localization, genetic influence, pathways, and shared protein domains. The important regulatory mechanisms of these networks involve miRNAs. We developed an R/Bioconductor package, namely SpidermiR, which offers an easy access to both GRNs and miRNAs to the end user, and integrates this information with differentially expressed genes obtained from The Cancer Genome Atlas. Specifically, SpidermiR allows the users to: (i) query and download GRNs and miRNAs from validated and predicted repositories; (ii) integrate miRNAs with GRNs in order to obtain miRNA-gene-gene and miRNA-protein-protein interactions, and to analyze miRNA GRNs in order to identify miRNA-gene communities; and (iii) graphically visualize the results of the analyses. These analyses can be performed through a single interface and without the need for any downloads. The full data sets are then rapidly integrated and processed locally.

Exploring the energy landscape of resistive switching in antiferromagnetic S r3I r2O7

NASA Astrophysics Data System (ADS)

Williamson, Morgan; Shen, Shida; Cao, Gang; Zhou, Jianshi; Goodenough, John B.; Tsoi, Maxim

2018-04-01

We study the resistive switching triggered by an applied electrical bias in the antiferromagnetic Mott insulator S r3I r2O7 . The switching was previously associated with an electric-field-driven structural transition. Here we use time-resolved measurements to probe the thermal activation behavior of the switching process and acquire information about the energy barrier associated with the transition. We quantify the changes in the energy-barrier height with respect to the applied bias and find a linear decrease of the barrier with increasing bias. Our observations support the potential of antiferromagnetic transition-metal oxides for spintronic applications.

Fabrication of (Co,Mn)3O4/rGO Composite for Lithium Ion Battery Anode by a One-Step Hydrothermal Process with H2O2 as Additive

PubMed Central

Li, Zuohua; Cui, Yanhui; Chen, Jun; Deng, Lianlin

2016-01-01

Binary transition metal oxides have been regarded as one of the most promising candidates for high-performance electrodes in energy storage devices, since they can offer high electrochemical activity and high capacity. Rational designing nanosized metal oxide/carbon composite architectures has been proven to be an effective way to improve the electrochemical performance. In this work, the (Co,Mn)3O4 spinel was synthesized and anchored on reduced graphene oxide (rGO) nanosheets using a facile and single hydrothermal step with H2O2 as additive, no further additional calcination required. Analysis showed that this method gives a mixed spinel, i.e. (Co,Mn)3O4, having 2+ and 3+ Co and Mn ions in both the octahedral and tetrahedral sites of the spinel structure, with a nanocubic morphology roughly 20 nm in size. The nanocubes are bound onto the rGO nanosheet uniformly in a single hydrothermal process, then the as-prepared (Co,Mn)3O4/rGO composite was characterized as the anode materials for Li-ion battery (LIB). It can deliver 1130.6 mAh g-1 at current density of 100 mA g-1 with 98% of coulombic efficiency after 140 cycles. At 1000 mA g-1, the capacity can still maintain 750 mAh g-1, demonstrating excellent rate capabilities. Therefore, the one-step process is a facile and promising method to fabricate metal oxide/rGO composite materials for energy storage applications. PMID:27788161

Fabrication of (Co,Mn)3O4/rGO Composite for Lithium Ion Battery Anode by a One-Step Hydrothermal Process with H2O2 as Additive.

PubMed

Li, Zuohua; Cui, Yanhui; Chen, Jun; Deng, Lianlin; Wu, Junwei

2016-01-01

Binary transition metal oxides have been regarded as one of the most promising candidates for high-performance electrodes in energy storage devices, since they can offer high electrochemical activity and high capacity. Rational designing nanosized metal oxide/carbon composite architectures has been proven to be an effective way to improve the electrochemical performance. In this work, the (Co,Mn)3O4 spinel was synthesized and anchored on reduced graphene oxide (rGO) nanosheets using a facile and single hydrothermal step with H2O2 as additive, no further additional calcination required. Analysis showed that this method gives a mixed spinel, i.e. (Co,Mn)3O4, having 2+ and 3+ Co and Mn ions in both the octahedral and tetrahedral sites of the spinel structure, with a nanocubic morphology roughly 20 nm in size. The nanocubes are bound onto the rGO nanosheet uniformly in a single hydrothermal process, then the as-prepared (Co,Mn)3O4/rGO composite was characterized as the anode materials for Li-ion battery (LIB). It can deliver 1130.6 mAh g-1 at current density of 100 mA g-1 with 98% of coulombic efficiency after 140 cycles. At 1000 mA g-1, the capacity can still maintain 750 mAh g-1, demonstrating excellent rate capabilities. Therefore, the one-step process is a facile and promising method to fabricate metal oxide/rGO composite materials for energy storage applications.

Reproducibility in Natural Language Processing: A Case Study of Two R Libraries for Mining PubMed/MEDLINE.

PubMed

Cohen, K Bretonnel; Xia, Jingbo; Roeder, Christophe; Hunter, Lawrence E

2016-05-01

There is currently a crisis in science related to highly publicized failures to reproduce large numbers of published studies. The current work proposes, by way of case studies, a methodology for moving the study of reproducibility in computational work to a full stage beyond that of earlier work. Specifically, it presents a case study in attempting to reproduce the reports of two R libraries for doing text mining of the PubMed/MEDLINE repository of scientific publications. The main findings are that a rational paradigm for reproduction of natural language processing papers can be established; the advertised functionality was difficult, but not impossible, to reproduce; and reproducibility studies can produce additional insights into the functioning of the published system. Additionally, the work on reproducibility lead to the production of novel user-centered documentation that has been accessed 260 times since its publication-an average of once a day per library.

Passing in Command Line Arguments and Parallel Cluster/Multicore Batching in R with batch.

PubMed

Hoffmann, Thomas J

2011-03-01

It is often useful to rerun a command line R script with some slight change in the parameters used to run it - a new set of parameters for a simulation, a different dataset to process, etc. The R package batch provides a means to pass in multiple command line options, including vectors of values in the usual R format, easily into R. The same script can be setup to run things in parallel via different command line arguments. The R package batch also provides a means to simplify this parallel batching by allowing one to use R and an R-like syntax for arguments to spread a script across a cluster or local multicore/multiprocessor computer, with automated syntax for several popular cluster types. Finally it provides a means to aggregate the results together of multiple processes run on a cluster.

On the functional role of human parietal cortex in number processing: How gender mediates the impact of a 'virtual lesion' induced by rTMS.

PubMed

Knops, Andre; Nuerk, Hans-Christoph; Sparing, Roland; Foltys, Henrik; Willmes, Klaus

2006-01-01

Areas around the horizontal part of the intraparietal sulcus (hIPS) have repeatedly been reported to participate in processing numerical magnitude. Using transcranial magnetic stimulation (TMS), we investigated the functional role of the hIPS by examining two effects from the domain of numerical cognition: in magnitude comparison tasks response latencies are inversely related to the numerical distance between two numbers. This distance effect indexes access to the mental number representation. In magnitude comparison tasks responses are faster when decade and unit comparison would lead to the same decision (e.g. 42_57, 4 < 5 and 2 < 7) than when they would not (e.g. 47_62, 4 < 6 but 7 > 2). This compatibility effect reflects unit-decade integration processes. Differential susceptibility of (fe)male participants to TMS was examined. We applied repetitive TMS (rTMS; 1Hz for 10 min) over the left hIPS in 12 participants (6 female). No stimulation and vertex stimulation served as control conditions. The effect of rTMS was mediated by gender: in male participants, the distance effect decreased after TMS over hIPS. For female participants distance and compatibility effect both increased. This modulation of the compatibility effect was limited in duration to no more than 4 min. The hIPS seems to be functionally involved both in number magnitude processing and in integrating unit-decade magnitude information of two-digit numbers. Relative hemispheric specialization of the hIPS with respect to two-digit magnitude comparison is discussed.

[Statistical analysis using freely-available "EZR (Easy R)" software].

PubMed

Kanda, Yoshinobu

2015-10-01

Clinicians must often perform statistical analyses for purposes such evaluating preexisting evidence and designing or executing clinical studies. R is a free software environment for statistical computing. R supports many statistical analysis functions, but does not incorporate a statistical graphical user interface (GUI). The R commander provides an easy-to-use basic-statistics GUI for R. However, the statistical function of the R commander is limited, especially in the field of biostatistics. Therefore, the author added several important statistical functions to the R commander and named it "EZR (Easy R)", which is now being distributed on the following website: http://www.jichi.ac.jp/saitama-sct/. EZR allows the application of statistical functions that are frequently used in clinical studies, such as survival analyses, including competing risk analyses and the use of time-dependent covariates and so on, by point-and-click access. In addition, by saving the script automatically created by EZR, users can learn R script writing, maintain the traceability of the analysis, and assure that the statistical process is overseen by a supervisor.

Current Status of the LOFAR EoR Key Science Project

NASA Astrophysics Data System (ADS)

Koopmans, L. V. E.; LOFAR EoR KSP Team

2018-05-01

A short status update on the LOFAR Epoch of Reionization (EoR) Key Science Project (KSP) is given, regarding data acquisition, data processing and analysis, and current power-spectrum limits on the redshifted 21-cm signal of neutral hydrogen at redshifts z = 8 - 10. With caution, we present a preliminary astrophysical analysis of ~60 hr of processed LOFAR data and their resulting power spectrum, showing that potentially already interesting limits on X-ray heating during the Cosmic Dawn can already be gained. This is by no means the final analysis of this sub-set of data, but illustrates the future potential when all nearly 3000 hr of data in hand on two EoR windows will have been processed.

Curve and Polygon Evolution Techniques for Image Processing

DTIC Science & Technology

2002-01-01

iterative image registration technique with an application to stereo vision. IJCAI, pages 674–679, 1981. 127 [93] R . Malladi , J.A. Sethian, and B.C...Notation A digital image to be processed is a 2-Dimensional (2-D) function denoted by I , I : ! R , where R2 is the domain of the function. Processing a...function Io(x; y), which depends on two spatial variables, x 2 R , and y 2 R , via a partial differential equation (PDE) takes the form; It = A(I; Ix

Lepton-flavor universality violation in R K and {R}_{D{_{(\\ast )}}} from warped space

NASA Astrophysics Data System (ADS)

Megías, Eugenio; Quirós, Mariano; Salas, Lindber

2017-07-01

Some anomalies in the processes b → sℓℓ ( ℓ = μ, e) and b\\to cℓ {\\overline{ν}}_{ℓ } ( ℓ = τ, μ, e), in particular in the observables R K and {R}_{D{_{(\\ast )}}} , have been found by the BaBar, LHCb and Belle collaborations, leading to a possible lepton flavor universality violation. If these anomalies were confirmed they would inevitably lead to physics beyond the Standard Model. In this paper we try to accommodate the present anomalies in an extra dimensional theory, solving the naturalness problem of the Standard Model by means of a warped metric with a strong conformality violation near the infra-red brane. The R K anomaly can be accommodated provided that the left-handed bottom quark and muon lepton have some degree of compositeness in the dual theory. The theory is consistent with all electroweak and flavor observables, and with all direct searches of Kaluza-Klein electroweak gauge bosons and gluons. The fermion spectrum, and fermion mixing angles, can be reproduced by mostly elementary right-handed bottom quarks, and tau and muon leptons. Moreover the {R}_{D{_{(\\ast )}}} anomaly requires a strong degree of compositeness for the left-handed tau leptons, which turns out to be in tension with experimental data on the {g}_{τ_L}^Z coupling, possibly unless some degree of fine-tuning is introduced in the fixing of the CKM matrix.

Hydrological analysis in R: Topmodel and beyond

NASA Astrophysics Data System (ADS)

Buytaert, W.; Reusser, D.

2011-12-01

R is quickly gaining popularity in the hydrological sciences community. The wide range of statistical and mathematical functionality makes it an excellent tool for data analysis, modelling and uncertainty analysis. Topmodel was one of the first hydrological models being implemented as an R package and distributed through R's own distribution network CRAN. This facilitated pre- and postprocessing of data such as parameter sampling, calculation of prediction bounds, and advanced visualisation. However, apart from these basic functionalities, the package did not use many of the more advanced features of the R environment, especially from R's object oriented functionality. With R's increasing expansion in arenas such as high performance computing, big data analysis, and cloud services, we revisit the topmodel package, and use it as an example of how to build and deploy the next generation of hydrological models. R provides a convenient environment and attractive features to build and couple hydrological - and in extension other environmental - models, to develop flexible and effective data assimilation strategies, and to take the model beyond the individual computer by linking into cloud services for both data provision and computing. However, in order to maximise the benefit of these approaches, it will be necessary to adopt standards and ontologies for model interaction and information exchange. Some of those are currently being developed, such as the OGC web processing standards, while other will need to be developed.

75 FR 41104 - Airworthiness Directives; Robinson Helicopter Company (Robinson) Model R22, R22 Alpha, R22 Beta...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-15

...-0711; Directorate Identifier 2008-SW-25-AD] RIN 2120-AA64 Airworthiness Directives; Robinson Helicopter Company (Robinson) Model R22, R22 Alpha, R22 Beta, and R22 Mariner Helicopters, and Model R44, and R44 II...). SUMMARY: This document proposes adopting a new airworthiness directive (AD) for Robinson Model R22, R22...

Comparative Aspects of Multiple Processes of Attention.

DTIC Science & Technology

1988-05-01

8217’ - % % -.. -. % $. Neisser , U . (1968). The processes of vision. Scientific American, 219, 201-214. Olson, R., & Attneave, F. (1970). What...AD-ft." M~ COMPARATIVE ASPECTS OF MULTIPLE PROCESSES OF ATTENTION 1/1 ( U ) DAYTON UNIV ON RESEARCH INST N CNEAL NAY U USI FE AFNRL-TR-9?-53 F3613-64-C...0% FOV9 M IR;. 2.2s 11U, XV11Y L. IIMrV % u AFHRL-TR-87-53 ~IF r- AIR FORCE R COMPARATIVE ASPECiS OF MULTIPLE PROCESSES OF ATTENTION _H U ’) U MaryLou

Spectroscopic identification of r-process nucleosynthesis in a double neutron-star merger.

PubMed

Pian, E; D'Avanzo, P; Benetti, S; Branchesi, M; Brocato, E; Campana, S; Cappellaro, E; Covino, S; D'Elia, V; Fynbo, J P U; Getman, F; Ghirlanda, G; Ghisellini, G; Grado, A; Greco, G; Hjorth, J; Kouveliotou, C; Levan, A; Limatola, L; Malesani, D; Mazzali, P A; Melandri, A; Møller, P; Nicastro, L; Palazzi, E; Piranomonte, S; Rossi, A; Salafia, O S; Selsing, J; Stratta, G; Tanaka, M; Tanvir, N R; Tomasella, L; Watson, D; Yang, S; Amati, L; Antonelli, L A; Ascenzi, S; Bernardini, M G; Boër, M; Bufano, F; Bulgarelli, A; Capaccioli, M; Casella, P; Castro-Tirado, A J; Chassande-Mottin, E; Ciolfi, R; Copperwheat, C M; Dadina, M; De Cesare, G; Di Paola, A; Fan, Y Z; Gendre, B; Giuffrida, G; Giunta, A; Hunt, L K; Israel, G L; Jin, Z-P; Kasliwal, M M; Klose, S; Lisi, M; Longo, F; Maiorano, E; Mapelli, M; Masetti, N; Nava, L; Patricelli, B; Perley, D; Pescalli, A; Piran, T; Possenti, A; Pulone, L; Razzano, M; Salvaterra, R; Schipani, P; Spera, M; Stamerra, A; Stella, L; Tagliaferri, G; Testa, V; Troja, E; Turatto, M; Vergani, S D; Vergani, D

2017-11-02

The merger of two neutron stars is predicted to give rise to three major detectable phenomena: a short burst of γ-rays, a gravitational-wave signal, and a transient optical-near-infrared source powered by the synthesis of large amounts of very heavy elements via rapid neutron capture (the r-process). Such transients, named 'macronovae' or 'kilonovae', are believed to be centres of production of rare elements such as gold and platinum. The most compelling evidence so far for a kilonova was a very faint near-infrared rebrightening in the afterglow of a short γ-ray burst at redshift z = 0.356, although findings indicating bluer events have been reported. Here we report the spectral identification and describe the physical properties of a bright kilonova associated with the gravitational-wave source GW170817 and γ-ray burst GRB 170817A associated with a galaxy at a distance of 40 megaparsecs from Earth. Using a series of spectra from ground-based observatories covering the wavelength range from the ultraviolet to the near-infrared, we find that the kilonova is characterized by rapidly expanding ejecta with spectral features similar to those predicted by current models. The ejecta is optically thick early on, with a velocity of about 0.2 times light speed, and reaches a radius of about 50 astronomical units in only 1.5 days. As the ejecta expands, broad absorption-like lines appear on the spectral continuum, indicating atomic species produced by nucleosynthesis that occurs in the post-merger fast-moving dynamical ejecta and in two slower (0.05 times light speed) wind regions. Comparison with spectral models suggests that the merger ejected 0.03 to 0.05 solar masses of material, including high-opacity lanthanides.

Celastrol Induces Autophagy by Targeting AR/miR-101 in Prostate Cancer Cells

PubMed Central

Guo, Jianquan; Huang, Xuemei; Wang, Hui; Yang, Huanjie

2015-01-01

Autophagy is an evolutionarily conserved process responsible for the degradation and recycling of cytoplasmic components through autolysosomes. Targeting AR axis is a standard strategy for prostate cancer treatment; however, the role of AR in autophagic processes is still not fully understood. In the present study, we found that AR played a negative role in AR degrader celastrol-induced autophagy. Knockdown of AR in AR-positive prostate cancer cells resulted in enhanced autophagy. Ectopic expression of AR in AR-negative prostate cancer cells, or gain of function of the AR signaling in AR-positive cells, led to suppression of autophagy. Since miR-101 is an inhibitor of autophagy and its expression was decreased along with AR in the process of celastrol-induced autophagy, we hypothesize that AR inhibits autophagy through transactivation of miR-101. AR binding site was defined in the upstream of miR-101 gene by luciferase reporter and ChIP assays. MiR-101 expression correlated with AR status in prostate cancer cell lines. The inhibition of celastrol-induced autophagy by AR was compromised by blocking miR-101; while transfection of miR-101 led to inhibition of celastrol-induced autophagy in spite of AR depletion. Furthermore, mutagenesis of the AR binding site in miR-101 gene led to decreased suppression of autophagy by AR. Finally, autophagy inhibition by miR-101 mimic was found to enhance the cytotoxic effect of celastrol in prostate cancer cells. Our results demonstrate that AR inhibits autophagy via transactivation of miR-101, thus combination of miR-101 mimics with celastrol may represent a promising therapeutic approach for treating prostate cancer. PMID:26473737

PaR-PaR laboratory automation platform.

PubMed

Linshiz, Gregory; Stawski, Nina; Poust, Sean; Bi, Changhao; Keasling, Jay D; Hillson, Nathan J

2013-05-17

Labor-intensive multistep biological tasks, such as the construction and cloning of DNA molecules, are prime candidates for laboratory automation. Flexible and biology-friendly operation of robotic equipment is key to its successful integration in biological laboratories, and the efforts required to operate a robot must be much smaller than the alternative manual lab work. To achieve these goals, a simple high-level biology-friendly robot programming language is needed. We have developed and experimentally validated such a language: Programming a Robot (PaR-PaR). The syntax and compiler for the language are based on computer science principles and a deep understanding of biological workflows. PaR-PaR allows researchers to use liquid-handling robots effectively, enabling experiments that would not have been considered previously. After minimal training, a biologist can independently write complicated protocols for a robot within an hour. Adoption of PaR-PaR as a standard cross-platform language would enable hand-written or software-generated robotic protocols to be shared across laboratories.

78 FR 63867 - Change of Using Agency for Restricted Areas R-5115, NM, and R-6316, R-6317, and R-6318, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

... realignment of organizational responsibilities between federal agencies, U.S. Customs and Border Protection..., R-6317, and R-6318 in Texas. The transfer of using agency operational control occurs October 1, 2013...-6316, R- 6317, and R-6318 to reflect current organizational responsibilities. Environmental Review The...

Preparation and modification of VO2 thin film on R-sapphire substrate by rapid thermal process

NASA Astrophysics Data System (ADS)

Zhu, Nai-Wei; Hu, Ming; Xia, Xiao-Xu; Wei, Xiao-Ying; Liang, Ji-Ran

2014-04-01

The VO2 thin film with high performance of metal-insulator transition (MIT) is prepared on R-sapphire substrate for the first time by magnetron sputtering with rapid thermal process (RTP). The electrical characteristic and THz transmittance of MIT in VO2 film are studied by four-point probe method and THz time domain spectrum (THz-TDS). X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and search engine marketing (SEM) are employed to analyze the crystalline structure, valence state, surface morphology of the film. Results indicate that the properties of VO2 film which is oxidized from the metal vanadium film in oxygen atmosphere are improved with a follow-up RTP modification in nitrogen atmosphere. The crystallization and components of VO2 film are improved and the film becomes compact and uniform. A better phase transition performance is shown that the resistance changes nearly 3 orders of magnitude with a 2-°C hysteresis width and the THz transmittances are reduced by 64% and 60% in thermal and optical excitation respectively.

Dead Element Replicating: Degenerate R2 Element Replication and rDNA Genomic Turnover in the Bacillus rossius Stick Insect (Insecta: Phasmida)

PubMed Central

Martoni, Francesco; Eickbush, Danna G.; Scavariello, Claudia; Luchetti, Andrea; Mantovani, Barbara

2015-01-01

R2 is an extensively investigated non-LTR retrotransposon that specifically inserts into the 28S rRNA gene sequences of a wide range of metazoans, disrupting its functionality. During R2 integration, first strand synthesis can be incomplete so that 5’ end deleted copies are occasionally inserted. While active R2 copies repopulate the locus by retrotransposing, the non-functional truncated elements should frequently be eliminated by molecular drive processes leading to the concerted evolution of the rDNA array(s). Although, multiple R2 lineages have been discovered in the genome of many animals, the rDNA of the stick insect Bacillus rossius exhibits a peculiar situation: it harbors both a canonical, functional R2 element (R2Brfun) as well as a full-length but degenerate element (R2Brdeg). An intensive sequencing survey in the present study reveals that all truncated variants in stick insects are present in multiple copies suggesting they were duplicated by unequal recombination. Sequencing results also demonstrate that all R2Brdeg copies are full-length, i. e. they have no associated 5' end deletions, and functional assays indicate they have lost the active ribozyme necessary for R2 RNA maturation. Although it cannot be completely ruled out, it seems unlikely that the degenerate elements replicate via reverse transcription, exploiting the R2Brfun element enzymatic machinery, but rather via genomic amplification of inserted 28S by unequal recombination. That inactive copies (both R2Brdeg or 5'-truncated elements) are not eliminated in a short term in stick insects contrasts with findings for the Drosophila R2, suggesting a widely different management of rDNA loci and a lower efficiency of the molecular drive while achieving the concerted evolution. PMID:25799008

Correlated receptor transport processes buffer single-cell heterogeneity

PubMed Central

Kallenberger, Stefan M.; Unger, Anne L.; Legewie, Stefan; Lymperopoulos, Konstantinos; Eils, Roland

2017-01-01

Cells typically vary in their response to extracellular ligands. Receptor transport processes modulate ligand-receptor induced signal transduction and impact the variability in cellular responses. Here, we quantitatively characterized cellular variability in erythropoietin receptor (EpoR) trafficking at the single-cell level based on live-cell imaging and mathematical modeling. Using ensembles of single-cell mathematical models reduced parameter uncertainties and showed that rapid EpoR turnover, transport of internalized EpoR back to the plasma membrane, and degradation of Epo-EpoR complexes were essential for receptor trafficking. EpoR trafficking dynamics in adherent H838 lung cancer cells closely resembled the dynamics previously characterized by mathematical modeling in suspension cells, indicating that dynamic properties of the EpoR system are widely conserved. Receptor transport processes differed by one order of magnitude between individual cells. However, the concentration of activated Epo-EpoR complexes was less variable due to the correlated kinetics of opposing transport processes acting as a buffering system. PMID:28945754

An R2R3-MYB Transcription Factor Regulates Eugenol Production in Ripe Strawberry Fruit Receptacles1

PubMed Central

Medina-Puche, Laura; Molina-Hidalgo, Francisco Javier; Boersma, Maaike; Schuurink, Robert C.; López-Vidriero, Irene; Solano, Roberto; Franco-Zorrilla, José-Manuel; Caballero, José Luis; Blanco-Portales, Rosario; Muñoz-Blanco, Juan

2015-01-01

Eugenol is a volatile phenylpropanoid that contributes to flower and ripe fruit scent. In ripe strawberry (Fragaria × ananassa) fruit receptacles, eugenol is biosynthesized by eugenol synthase (FaEGS2). However, the transcriptional regulation of this process is still unknown. We have identified and functionally characterized an R2R3 MYB transcription factor (EMISSION OF BENZENOID II [FaEOBII]) that seems to be the orthologous gene of PhEOBII from Petunia hybrida, which contributes to the regulation of eugenol biosynthesis in petals. The expression of FaEOBII was ripening related and fruit receptacle specific, although high expression values were also found in petals. This expression pattern of FaEOBII correlated with eugenol content in both fruit receptacle and petals. The expression of FaEOBII was repressed by auxins and activated by abscisic acid, in parallel to the ripening process. In ripe strawberry receptacles, where the expression of FaEOBII was silenced, the expression of CINNAMYL ALCOHOL DEHYDROGENASE1 and FaEGS2, two structural genes involved in eugenol production, was down-regulated. A subsequent decrease in eugenol content in ripe receptacles was also observed, confirming the involvement of FaEOBII in eugenol metabolism. Additionally, the expression of FaEOBII was under the control of FaMYB10, another R2R3 MYB transcription factor that regulates the early and late biosynthetic genes from the flavonoid/phenylpropanoid pathway. In parallel, the amount of eugenol in FaMYB10-silenced receptacles was also diminished. Taken together, these data indicate that FaEOBII plays a regulating role in the volatile phenylpropanoid pathway gene expression that gives rise to eugenol production in ripe strawberry receptacles. PMID:25931522

Double ionization in R -matrix theory using a two-electron outer region

NASA Astrophysics Data System (ADS)

Wragg, Jack; Parker, J. S.; van der Hart, H. W.

2015-08-01

We have developed a two-electron outer region for use within R -matrix theory to describe double ionization processes. The capability of this method is demonstrated for single-photon double ionization of He in the photon energy region between 80 and 180 eV. The cross sections are in agreement with established data. The extended R -matrix with time dependence method also provides information on higher-order processes, as demonstrated by the identification of signatures for sequential double ionization processes involving an intermediate He+ state with n =2 .

R parity violation from discrete R symmetries

DOE PAGES

Chen, Mu-Chun; Ratz, Michael; Takhistov, Volodymyr

2014-12-15

We consider supersymmetric extensions of the standard model in which the usual R or matter parity gets replaced by another R or non–R discrete symmetry that explains the observed longevity of the nucleon and solves the µ problem of MSSM. In order to identify suitable symmetries, we develop a novel method of deriving the maximal Z (R) N symmetry that satisfies a given set of constraints. We identify R parity violating (RPV) and conserving models that are consistent with precision gauge unification and also comment on their compatibility with a unified gauge symmetry such as the Pati–Salam group. Finally, wemore » provide a counter– example to the statement found in the recent literature that the lepton number violating RPV scenarios must have µ term and the bilinear κ L Hu operator of comparable magnitude.« less

Reproducibility in Natural Language Processing: A Case Study of Two R Libraries for Mining PubMed/MEDLINE

PubMed Central

Cohen, K. Bretonnel; Xia, Jingbo; Roeder, Christophe; Hunter, Lawrence E.

2018-01-01

There is currently a crisis in science related to highly publicized failures to reproduce large numbers of published studies. The current work proposes, by way of case studies, a methodology for moving the study of reproducibility in computational work to a full stage beyond that of earlier work. Specifically, it presents a case study in attempting to reproduce the reports of two R libraries for doing text mining of the PubMed/MEDLINE repository of scientific publications. The main findings are that a rational paradigm for reproduction of natural language processing papers can be established; the advertised functionality was difficult, but not impossible, to reproduce; and reproducibility studies can produce additional insights into the functioning of the published system. Additionally, the work on reproducibility lead to the production of novel user-centered documentation that has been accessed 260 times since its publication—an average of once a day per library. PMID:29568821

Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis.

PubMed

Drout, M R; Piro, A L; Shappee, B J; Kilpatrick, C D; Simon, J D; Contreras, C; Coulter, D A; Foley, R J; Siebert, M R; Morrell, N; Boutsia, K; Di Mille, F; Holoien, T W-S; Kasen, D; Kollmeier, J A; Madore, B F; Monson, A J; Murguia-Berthier, A; Pan, Y-C; Prochaska, J X; Ramirez-Ruiz, E; Rest, A; Adams, C; Alatalo, K; Bañados, E; Baughman, J; Beers, T C; Bernstein, R A; Bitsakis, T; Campillay, A; Hansen, T T; Higgs, C R; Ji, A P; Maravelias, G; Marshall, J L; Bidin, C Moni; Prieto, J L; Rasmussen, K C; Rojas-Bravo, C; Strom, A L; Ulloa, N; Vargas-González, J; Wan, Z; Whitten, D D

2017-12-22

On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe. Copyright © 2017, American Association for the Advancement of Science.

SSB-1 of the yeast Saccharomyces cerevisiae is a nucleolar-specific, silver-binding protein that is associated with the snR10 and snR11 small nuclear RNAs

PubMed Central

1990-01-01

SSB-1, the yeast single-strand RNA-binding protein, is demonstrated to be a yeast nucleolar-specific, silver-binding protein. In double-label immunofluorescence microscopy experiments antibodies to two other nucleolar proteins, RNA Pol I 190-kD and fibrillarin, were used to reveal the site of rRNA transcription; i.e., the fibrillar region of the nucleolus. SSB-1 colocalized with fibrillarin in a double-label immunofluorescence mapping experiment to the yeast nucleolus. SSB-1 is located, though, over a wider region of the nucleolus than the transcription site marker. Immunoprecipitations of yeast cell extracts with the SSB-1 antibody reveal that in 150 mM NaCl SSB-1 is bound to two small nuclear RNAs (snRNAs). These yeast snRNAs are snR10 and snR11, with snR10 being predominant. Since snR10 has been implicated in pre-rRNA processing, the association of SSB-1 and snR10 into a nucleolar snRNP particle indicates SSB-1 involvement in rRNA processing as well. Also, another yeast protein, SSB-36-kD, isolated by single- strand DNA chromatography, is shown to bind silver under the conditions used for nucleolar-specific staining. It is, most likely, another yeast nucleolar protein. PMID:2121740

Differentiation of Forebrain and Hippocampal Dopamine 1-Class Receptors, D1R and D5R, in Spatial Learning and Memory

PubMed Central

Sariñana, Joshua; Tonegawa, Susumu

2017-01-01

Activation of prefrontal cortical (PFC), striatal, and hippocampal dopamine 1-class receptors (D1R and D5R) is necessary for normal spatial information processing. Yet the precise role of the D1R versus the D5R in the aforementioned structures, and their specific contribution to the water-maze spatial learning task remains unknown. D1R- and D5R- specific in situ hybridization probes showed that forebrain restricted D1R and D5R KO mice (F-D1R/D5R KO) displayed D1R mRNA deletion in the medial (m)PFC, dorsal and ventral striatum, and the dentate gyrus (DG) of the hippocampus. D5R mRNA deletion was limited to the mPFC, the CA1 and DG hippocampal subregions. F-D1R/D5R KO mice were given water-maze training and displayed subtle spatial latency differences between genotypes and spatial memory deficits during both regular and reversal training. To differentiate forebrain D1R from D5R activation, forebrain restricted D1R KO (F-D1R KO) and D5R KO (F-D5R KO) mice were trained on the water-maze task. F-D1R KO animals exhibited escape latency deficits throughout regular and reversal training as well as spatial memory deficits during reversal training. F-D1R KO mice also showed perseverative behavior during the reversal spatial memory probe test. In contrast, F-D5R KO animals did not present observable deficits on the water-maze task. Because F-D1R KO mice showed water-maze deficits we tested the necessity of hippocampal D1R activation for spatial learning and memory. We trained DG restricted D1R KO (DG-D1R KO) mice on the water-maze task. DG-D1R KO mice did not present detectable spatial memory deficit, but did show subtle deficits during specific days of training. Our data provides evidence that forebrain D5R activation plays a unique role in spatial learning and memory in conjunction with D1R activation. Moreover, these data suggest that mPFC and striatal, but not DG D1R activation are essential for spatial learning and memory. PMID:26174222

Bio-preparation of (R)-DMPM using whole cells of Pseudochrobactrum asaccharolyticum WZZ003 and its application on kilogram-scale synthesis of fungicide (R)-metalaxyl.

PubMed

Zhang, Yinjun; Fan, Yicheng; Zhang, Wei; Wu, Guanzhong; Wang, Jinghong; Cheng, Feng; Zheng, Jianyong; Wang, Zhao

2018-04-25

Methyl (R)-N-(2,6-dimethylphenyl)alaninate ((R)-DMPM) is a key chiral intermediate for the production of (R)-metalaxyl, which is one of the best-selling fungicides. A new strain, Pseudochrobactrum asaccharolyticum WZZ003, was identified as a biocatalyst for the enantioselective hydrolysis of (R,S)-DMPM. The key parameters including pH, temperature, rotation speed and substrate concentrations were optimized in the enantioselective hydrolysis of (R,S)-DMPM. After the 48 h hydrolysis of 256 mM (R,S)-DMPM under the optimized reaction conditions, the enantiomeric excess of product (e.e. p ) was up to 99% and the conversion was nearly 50%. Subsequently, the unhydrolyzed (S)-DMPM was converted to (R,S)-DMPM through the n-butanal-catalyzed racemization. Furthermore, stereoselective hydrolysis of (R,S)-DMPM catalyzed by whole cells of P. asaccharolyticum WZZ003 was scaled up to kilogram-scale, offering (R)-MAP-acid with 98.6% e.e. p and 48.0% yield. Moreover, (R)-metalaxyl was prepared at kilogram scale after subsequent esterification and coupling reactions. Therefore, a practical production process of (R)-DMPM and (R)-metalaxyl with the prospect of industrialization was developed in this study. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

GOES-R Arrival and Offload

NASA Image and Video Library

2016-08-22

A truck with a specialized transporter drives away from an Air Force C-5 Galaxy transport plane at the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida to deliver the GOES-R spacecraft for launch processing. The GOES series are weather satellites operated by NOAA to enhance forecasts. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

High-Precision Mass Measurement of Cu 56 and the Redirection of the r p -Process Flow

NASA Astrophysics Data System (ADS)

Valverde, A. A.; Brodeur, M.; Bollen, G.; Eibach, M.; Gulyuz, K.; Hamaker, A.; Izzo, C.; Ong, W.-J.; Puentes, D.; Redshaw, M.; Ringle, R.; Sandler, R.; Schwarz, S.; Sumithrarachchi, C. S.; Surbrook, J.; Villari, A. C. C.; Yandow, I. T.

2018-01-01

We report the mass measurement of Cu 56 , using the LEBIT 9.4 T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of Cu 56 is critical for constraining the reaction rates of the Ni 55 (p ,γ ) Cu 56 (p ,γ ) Zn 57 (β+) Cu 57 bypass around the Ni 56 waiting point. Previous recommended mass excess values have disagreed by several hundred keV. Our new value, ME =-38 626.7 (7.1 ) keV , is a factor of 30 more precise than the extrapolated value suggested in the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012), 10.1088/1674-1137/36/12/003], and more than a factor of 12 more precise than values calculated using local mass extrapolations, while agreeing with the newest 2016 atomic mass evaluation value [Chin. Phys. C 41, 030003 (2017), 10.1088/1674-1137/41/3/030003]. The new experimental average, using our new mass and the value from AME2016, is used to calculate the astrophysical Ni 55 (p ,γ ) and Cu 56 (p ,γ ) forward and reverse rates and perform reaction network calculations of the r p process. These show that the r p -process flow redirects around the Ni 56 waiting point through the Ni 55 (p ,γ ) route, allowing it to proceed to higher masses more quickly and resulting in a reduction in ashes around this waiting point and an enhancement to higher-mass ashes.

AhR-deficiency as a cause of demyelinating disease and inflammation.

PubMed

Juricek, Ludmila; Carcaud, Julie; Pelhaitre, Alice; Riday, Thorfinn T; Chevallier, Aline; Lanzini, Justine; Auzeil, Nicolas; Laprévote, Olivier; Dumont, Florent; Jacques, Sebastien; Letourneur, Frank; Massaad, Charbel; Agulhon, Cendra; Barouki, Robert; Beraneck, Mathieu; Coumoul, Xavier

2017-08-29

The Aryl hydrocarbon Receptor(AhR) is among the most important receptors which bind pollutants; however it also regulates signaling pathways independently of such exposure. We previously demonstrated that AhR is expressed during development of the central nervous system(CNS) and that its deletion leads to the occurrence of a congenital nystagmus. Objectives of the present study are to decipher the origin of these deficits, and to identify the role of the AhR in the development of the CNS. We show that the AhR-knockout phenotype develops during early infancy together with deficits in visual-information-processing which are associated with an altered optic nerve myelin sheath, which exhibits modifications in its lipid composition and in the expression of myelin-associated-glycoprotein(MAG), a cell adhesion molecule involved in myelin-maintenance and glia-axon interaction. In addition, we show that the expression of pro-inflammatory cytokines is increased in the impaired optic nerve and confirm that inflammation is causally related with an AhR-dependent decreased expression of MAG. Overall, our findings demonstrate the role of the AhR as a physiological regulator of myelination and inflammatory processes in the developing CNS. It identifies a mechanism by which environmental pollutants might influence CNS myelination and suggest AhR as a relevant drug target for demyelinating diseases.

Scientific R&D: time to revise the rules?

PubMed

Crump, Andy

2004-11-01

For several decades scientific R&D has been failing communities around the world, especially in developing countries, by not producing an adequate level of benefits (for example, improved health and living standards) and essential public goods (for example, the provision of safe water, sanitation and energy). It is time for a complete overhaul of the R&D process, with a comprehensive review of the mechanisms by which R&D is financed, how and where the work and results are published and disseminated, how the results and knowledge are exploited, and how ownership is decided. This is particularly important for public goods, for which there is often no market or prospect of commercial return or profit.

NREL Research Team Wins R&D 100 Award | News | NREL

Science.gov Websites

performance PV modules for large-scale solar power plants, commercial and residential buildings, and off-grid Laboratory (NREL) and First Solar have been selected to receive a 2003 R&D 100 award from R&D Magazine for developing a new process for depositing semiconductor layers onto photovoltaic (PV) modules

The Geostationary Operational Satellite R Series SpaceWire Based Data System

NASA Technical Reports Server (NTRS)

Anderson, William; Birmingham, Michael; Krimchansky, Alexander; Lombardi, Matthew

2016-01-01

The Geostationary Operational Environmental Satellite R-Series Program (GOES-R, S, T, and U) mission is a joint program between National Oceanic & Atmospheric Administration (NOAA) and National Aeronautics & Space Administration (NASA) Goddard Space Flight Center (GSFC). SpaceWire was selected as the science data bus as well as command and telemetry for the GOES instruments. GOES-R, S, T, and U spacecraft have a mission data loss requirement for all data transfers between the instruments and spacecraft requiring error detection and correction at the packet level. The GOES-R Reliable Data Delivery Protocol (GRDDP) [1] was developed in house to provide a means of reliably delivering data among various on board sources and sinks. The GRDDP was presented to and accepted by the European Cooperation for Space Standardization (ECSS) and is part of the ECSS Protocol Identification Standard [2]. GOES-R development and integration is complete and the observatory is scheduled for launch November 2016. Now that instrument to spacecraft integration is complete, GOES-R Project reviewed lessons learned to determine how the GRDDP could be revised to improve the integration process. Based on knowledge gained during the instrument to spacecraft integration process the following is presented to help potential GRDDP users improve their system designs and implementation.

75 FR 71532 - Airworthiness Directives; Robinson Helicopter Company (Robinson) Model R22, R22 Alpha, R22 Beta...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-24

... Airworthiness Directives; Robinson Helicopter Company (Robinson) Model R22, R22 Alpha, R22 Beta, and R22 Mariner... rule. SUMMARY: This amendment adopts a new airworthiness directive (AD) for Robinson Model R22, R22... Robinson Helicopter Company, 2901 Airport Drive, Torrance, California 90505, telephone (310) 539-0508, fax...

Shifting towards a model of mGluR5 dysregulation in schizophrenia: Consequences for future schizophrenia treatment.

PubMed

Matosin, Natalie; Fernandez-Enright, Francesca; Lum, Jeremy S; Newell, Kelly A

2017-03-15

Metabotropic glutamate receptor subtype 5 (mGluR5), encoded by the GRM5 gene, represents a compelling novel drug target for the treatment of schizophrenia. mGluR5 is a postsynaptic G-protein coupled glutamate receptor strongly linked with several critical cellular processes that are reported to be disrupted in schizophrenia. Accordingly, mGluR5 positive allosteric modulators show encouraging therapeutic potential in preclinical schizophrenia models, particularly for the treatment of cognitive dysfunctions against which currently available therapeutics are largely ineffective. More work is required to support the progression of mGluR5-targeting drugs into the clinic for schizophrenia treatment, although some obstacles may be overcome by comprehensively understanding how mGluR5 itself is involved in the neurobiology of the disorder. Several processes that are necessary for the regulation of mGluR5 activity have been identified, but not examined, in the context of schizophrenia. These processes include protein-protein interactions, dimerisation, subcellular trafficking, the impact of genetic variability or mutations on protein function, as well as epigenetic, post-transcriptional and post-translational processes. It is essential to understand these aspects of mGluR5 to determine whether they are affected in schizophrenia pathology, and to assess the consequences of mGluR5 dysfunction for the future use of mGluR5-based drugs. Here, we summarise the known processes that regulate mGluR5 and those that have already been studied in schizophrenia, and discuss the consequences of this dysregulation for current mGluR5 pharmacological strategies. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'. Copyright © 2015 Elsevier Ltd. All rights reserved.

miR-Let7A Modulates Autophagy Induction in LPS-Activated Microglia

PubMed Central

Song, Juhyun; Oh, Yumi

2015-01-01

Microglia regulate the secretion of various immunomediators in central nervous system diseases. Microglial autophagy is the crucial process for cell's survival and cytokine productions. Recent studies have reported that several microRNAs are involved in the autophagy system. miR-Let7A is such a microRNA that plays a role in various inflammation responses, and is magnified as a key modulator particularly in the autophagy system. In present study, we investigated whether miR-Let7A is involved in autophagy in activating microglia. Overexpression of miR-Let7A in LPS-stimulated BV2 microglial cells promoted the induction of the autophagy related factors such as LC3II, Beclin1, and ATG3. Our results suggest a potential role of miR-Let7A in the autophagy process of microglia during CNS inflammation. PMID:26113790

The 28S–18S rDNA intergenic spacer from Crithidia fasciculata: repeated sequences, length heterogeneity, putative processing sites and potential interactions between U3 small nucleolar RNA and the ribosomal RNA precursor

PubMed Central

Schnare, Murray N.; Collings, James C.; Spencer, David F.; Gray, Michael W.

2000-01-01

In Crithidia fasciculata, the ribosomal RNA (rRNA) gene repeats range in size from ∼11 to 12 kb. This length heterogeneity is localized to a region of the intergenic spacer (IGS) that contains tandemly repeated copies of a 19mer sequence. The IGS also contains four copies of an ∼55 nt repeat that has an internal inverted repeat and is also present in the IGS of Leishmania species. We have mapped the C.fasciculata transcription initiation site as well as two other reverse transcriptase stop sites that may be analogous to the A0 and A′ pre-rRNA processing sites within the 5′ external transcribed spacer (ETS) of other eukaryotes. Features that could influence processing at these sites include two stretches of conserved primary sequence and three secondary structure elements present in the 5′ ETS. We also characterized the C.fasciculata U3 snoRNA, which has the potential for base-pairing with pre-rRNA sequences. Finally, we demonstrate that biosynthesis of large subunit rRNA in both C.fasciculata and Trypanosoma brucei involves 3′-terminal addition of three A residues that are not present in the corresponding DNA sequences. PMID:10982863

Regulated expression of a repressor protein: FadR activates iclR.

PubMed Central

Gui, L; Sunnarborg, A; LaPorte, D C

1996-01-01

The control of the glyoxylate bypass operon (aceBAK) of Escherichia coli is mediated by two regulatory proteins, IclMR and FadR. IclMR is a repressor protein which has previously been shown to bind to a site which overlaps the aceBAK promoter. FAR is a repressor/activator protein which participates in control of the genes of fatty acid metabolism. A sequence just upstream of the iclR promoter bears a striking resemblance to FadR binding sites found in the fatty acid metabolic genes. The in vitro binding specificity of FadR, determined by oligonucleotide selection, was in good agreement with the sequences of these sites. The ability of FadR to bind to the site associated with iclR was demonstrated by gel shift and DNase I footprint analyses. Disruption of FadR or inactivation of the FadR binding site of iclR decreased the expression of an iclR::lacZ operon fusion, indicating that FadR activates the expression of iclR. It has been reported that disruption of fadR increases the expression of aceBAK. We observed a similar increase when we inactivated the FadR binding site of an iclR+ allele. This result suggests that FadR regulates aceBAK indirectly by altering the expression of IclR. PMID:8755903

Information Commons for Rice (IC4R)

PubMed Central

2016-01-01

Rice is the most important staple food for a large part of the world's human population and also a key model organism for plant research. Here, we present Information Commons for Rice (IC4R; http://ic4r.org), a rice knowledgebase featuring adoption of an extensible and sustainable architecture that integrates multiple omics data through community-contributed modules. Each module is developed and maintained by different committed groups, deals with data collection, processing and visualization, and delivers data on-demand via web services. In the current version, IC4R incorporates a variety of rice data through multiple committed modules, including genome-wide expression profiles derived entirely from RNA-Seq data, resequencing-based genomic variations obtained from re-sequencing data of thousands of rice varieties, plant homologous genes covering multiple diverse plant species, post-translational modifications, rice-related literatures and gene annotations contributed by the rice research community. Unlike extant related databases, IC4R is designed for scalability and sustainability and thus also features collaborative integration of rice data and low costs for database update and maintenance. Future directions of IC4R include incorporation of other omics data and association of multiple omics data with agronomically important traits, dedicating to build IC4R into a valuable knowledgebase for both basic and translational researches in rice. PMID:26519466

Assessment of Advanced Coal Gasification Processes

NASA Technical Reports Server (NTRS)

McCarthy, John; Ferrall, Joseph; Charng, Thomas; Houseman, John

1981-01-01

This report represents a technical assessment of the following advanced coal gasification processes: AVCO High Throughput Gasification (HTG) Process; Bell Single-Stage High Mass Flux (HMF) Process; Cities Service/Rockwell (CS/R) Hydrogasification Process; Exxon Catalytic Coal Gasification (CCG) Process. Each process is evaluated for its potential to produce SNG from a bituminous coal. In addition to identifying the new technology these processes represent, key similarities/differences, strengths/weaknesses, and potential improvements to each process are identified. The AVCO HTG and the Bell HMF gasifiers share similarities with respect to: short residence time (SRT), high throughput rate, slagging and syngas as the initial raw product gas. The CS/R Hydrogasifier is also SRT but is non-slagging and produces a raw gas high in methane content. The Exxon CCG gasifier is a long residence time, catalytic, fluidbed reactor producing all of the raw product methane in the gasifier. The report makes the following assessments: 1) while each process has significant potential as coal gasifiers, the CS/R and Exxon processes are better suited for SNG production; 2) the Exxon process is the closest to a commercial level for near-term SNG production; and 3) the SRT processes require significant development including scale-up and turndown demonstration, char processing and/or utilization demonstration, and reactor control and safety features development.

Optical performance of random anti-reflection structured surfaces (rARSS) on spherical lenses

NASA Astrophysics Data System (ADS)

Taylor, Courtney D.

Random anti-reflection structured surfaces (rARSS) have been reported to improve transmittance of optical-grade fused silica planar substrates to values greater than 99%. These textures are fabricated directly on the substrates using reactive-ion/inductively-coupled plasma etching (RIE/ICP) techniques, and often result in transmitted spectra with no measurable interference effects (fringes) for a wide range of wavelengths. The RIE/ICP processes used in the fabrication process to etch the rARSS is anisotropic and thus well suited for planar components. The improvement in spectral transmission has been found to be independent of optical incidence angles for values from 0° to +/-30°. Qualifying and quantifying the rARSS performance on curved substrates, such as convex lenses, is required to optimize the fabrication of the desired AR effect on optical-power elements. In this work, rARSS was fabricated on fused silica plano-convex (PCX) and plano-concave (PCV) lenses using a planar-substrate optimized RIE process to maximize optical transmission in the range from 500 to 1100 nm. An additional set of lenses were etched in a non-optimized ICP process to provide additional comparisons. Results are presented from optical transmission and beam propagation tests (optimized lenses only) of rARSS lenses for both TE and TM incident polarizations at a wavelength of 633 nm and over a 70° full field of view in both singlet and doublet configurations. These results suggest optimization of the fabrication process is not required, mainly due to the wide angle-of-incidence AR tolerance performance of the rARSS lenses. Non-optimized recipe lenses showed low transmission enhancement, and confirmed the need to optimized etch recipes prior to process transfer of PCX/PCV lenses. Beam propagation tests indicated no major beam degradation through the optimized lens elements. Scanning electron microscopy (SEM) images confirmed different structure between optimized and non-optimized samples

GOES-R Arrival and Offload

NASA Image and Video Library

2016-08-22

A truck with a specialized transporter drives out of the cargo hold of an Air Force C-5 Galaxy transport plane at the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida to deliver the GOES-R spacecraft for launch processing. The GOES series are weather satellites operated by NOAA to enhance forecasts. The spacecraft is to launch aboard a United Launch Alliance Atlas V rocket in November.

elPBN neurons regulate rVLM activity through elPBN-rVLM projections during activation of cardiac sympathetic afferent nerves

PubMed Central

Longhurst, John C.; Tjen-A-Looi, Stephanie C.; Fu, Liang-Wu

2016-01-01

The external lateral parabrachial nucleus (elPBN) within the pons and rostral ventrolateral medulla (rVLM) contributes to central processing of excitatory cardiovascular reflexes during stimulation of cardiac sympathetic afferent nerves (CSAN). However, the importance of elPBN cardiovascular neurons in regulation of rVLM activity during CSAN activation remains unclear. We hypothesized that CSAN stimulation excites the elPBN cardiovascular neurons and, in turn, increases rVLM activity through elPBN-rVLM projections. Compared with controls, in rats subjected to microinjection of retrograde tracer into the rVLM, the numbers of elPBN neurons double-labeled with c-Fos (an immediate early gene) and the tracer were increased after CSAN stimulation (P < 0.05). The majority of these elPBN neurons contain vesicular glutamate transporter 3. In cats, epicardial bradykinin and electrical stimulation of CSAN increased the activity of elPBN cardiovascular neurons, which was attenuated (n = 6, P < 0.05) after blockade of glutamate receptors with iontophoresis of kynurenic acid (Kyn, 25 mM). In separate cats, microinjection of Kyn (1.25 nmol/50 nl) into the elPBN reduced rVLM activity evoked by both bradykinin and electrical stimulation (n = 5, P < 0.05). Excitation of the elPBN with microinjection of dl-homocysteic acid (2 nmol/50 nl) significantly increased basal and CSAN-evoked rVLM activity. However, the enhanced rVLM activity induced by dl-homocysteic acid injected into the elPBN was reversed following iontophoresis of Kyn into the rVLM (n = 7, P < 0.05). These data suggest that cardiac sympathetic afferent stimulation activates cardiovascular neurons in the elPBN and rVLM sequentially through a monosynaptic (glutamatergic) excitatory elPBN-rVLM pathway. PMID:27225950

GOES-R GS Product Generation Infrastructure Operations

NASA Astrophysics Data System (ADS)

Blanton, M.; Gundy, J.

2012-12-01

GOES-R GS Product Generation Infrastructure Operations: The GOES-R Ground System (GS) will produce a much larger set of products with higher data density than previous GOES systems. This requires considerably greater compute and memory resources to achieve the necessary latency and availability for these products. Over time, new algorithms could be added and existing ones removed or updated, but the GOES-R GS cannot go down during this time. To meet these GOES-R GS processing needs, the Harris Corporation will implement a Product Generation (PG) infrastructure that is scalable, extensible, extendable, modular and reliable. The primary parts of the PG infrastructure are the Service Based Architecture (SBA), which includes the Distributed Data Fabric (DDF). The SBA is the middleware that encapsulates and manages science algorithms that generate products. The SBA is divided into three parts, the Executive, which manages and configures the algorithm as a service, the Dispatcher, which provides data to the algorithm, and the Strategy, which determines when the algorithm can execute with the available data. The SBA is a distributed architecture, with services connected to each other over a compute grid and is highly scalable. This plug-and-play architecture allows algorithms to be added, removed, or updated without affecting any other services or software currently running and producing data. Algorithms require product data from other algorithms, so a scalable and reliable messaging is necessary. The SBA uses the DDF to provide this data communication layer between algorithms. The DDF provides an abstract interface over a distributed and persistent multi-layered storage system (memory based caching above disk-based storage) and an event system that allows algorithm services to know when data is available and to get the data that they need to begin processing when they need it. Together, the SBA and the DDF provide a flexible, high performance architecture that can meet

Current status and prospects of radiation processing studies in Taiwan, R. O. C.

NASA Astrophysics Data System (ADS)

Fu, Ying-Kai

The research on radiation processing in past 5 years in Taiwan covers industrial application of radiation-induced polymerization and curing, medical application of radiosterilization of medical supplies, chemicals, and amniotic membrane for wound dressing as well as agricultural application of food irradiation and genogenesis etc. Radiation-induced polymerization applied on wood and bamboo plastic composite of methyl methacrylate, radiation curing on polyurethane and silicon rubber for biomedical material using to separate oxygen from nitrogen and on crosslinking of pp and ps for artificial skin for wound dressing were all success. Radio-sterilization of disposable medical supplies appears for immediate application after the studies of the dose requirement of several radioresistant microorganisms, dose distribution measured by chemical dosimeters of ceric sulfate and Fricke dosimeter as well as quality control system were completed. The radiosterilization study of tetracycline - HCl and few detoxic agents like atropine sulfate and toxogonin has shown the promising results on radiosterilization of chemicals, the radiosterilization of amniotic membrane for wound dressing are also success. Food irradiation on sprouting inhibition of potatoes, garlic etc, on radiodisinfestation of cereal insects, tobacco bettles, soybean insects, and flour beetles, as well as on frog legs and porks have been also discussed. The legislation on radiosterilization of medical supplies and food irradiation of 14 items has been approved by National Health Administration, R.O.C. in July of 1982 and January of 1985 respectively. Even 24 hrs-operation of 1 Mega curie irradiation plant at INER can not satisfy the requirement of radiosterilization of medical supplies. A private commercial irradiation plant is urgently needed in Taiwan other than at INER now.

miR-203 modulates epithelial differentiation of human embryonic stem cells towards epidermal stratification.

PubMed

Nissan, Xavier; Denis, Jérôme Alexandre; Saidani, Manoubia; Lemaitre, Gilles; Peschanski, Marc; Baldeschi, Christine

2011-08-15

The molecular mechanisms controlling the differentiation of human basal keratinocyte stem cells towards the epidermis are well characterized, whereas the earliest process leading to the specification of embryonic stem cells into keratinocytes is still not well understood. MicroRNAs are regulators of many cellular events, but evidence for microRNA acting on the differentiation of human embryonic stem cells into a specific lineage has been elusive. By using our recent protocol for obtaining functional keratinocytes from hESC, we attempted to analyze the role of microRNAs in the early stages of epidermal differentiation. Thus, we identified a set of 5 microRNAs, namely miR-200a, miR-200b, miR-203, miR-205 and miR-429, that are specifically overexpressed during the early stages of the differentiation process. Interestingly, our functional analyses revealed an instrumental role of miR-203, which had been previously shown to play a key role during the formation of the pluristratified epidermis by basal keratinocyte stem cells, in the early keratinocyte commitment. These results highlight the determinant and unique role of miR-203 during the entire process of epidermal development by extending its spectrum of action from the early commitment of embryonic stem cells to ultimate differentiation of the organ. Copyright © 2011 Elsevier Inc. All rights reserved.

R-CMap-An open-source software for concept mapping.

PubMed

Bar, Haim; Mentch, Lucas

2017-02-01

Planning and evaluating projects often involves input from many stakeholders. Fusing and organizing many different ideas, opinions, and interpretations into a coherent and acceptable plan or project evaluation is challenging. This is especially true when seeking contributions from a large number of participants, especially when not all can participate in group discussions, or when some prefer to contribute their perspectives anonymously. One of the major breakthroughs in the area of evaluation and program planning has been the use of graphical tools to represent the brainstorming process. This provides a quantitative framework for organizing ideas and general concepts into simple-to-interpret graphs. We developed a new, open-source concept mapping software called R-CMap, which is implemented in R. This software provides a graphical user interface to guide users through the analytical process of concept mapping. The R-CMap software allows users to generate a variety of plots, including cluster maps, point rating and cluster rating maps, as well as pattern matching and go-zone plots. Additionally, R-CMap is capable of generating detailed reports that contain useful statistical summaries of the data. The plots and reports can be embedded in Microsoft Office tools such as Word and PowerPoint, where users may manually adjust various plot and table features to achieve the best visual results in their presentations and official reports. The graphical user interface of R-CMap allows users to define cluster names, change the number of clusters, select rating variables for relevant plots, and importantly, select subsets of respondents by demographic criteria. The latter is particularly useful to project managers in order to identify different patterns of preferences by subpopulations. R-CMap is user-friendly, and does not require any programming experience. However, proficient R users can add to its functionality by directly accessing built-in functions in R and sharing new

THE INTERMEDIATE NEUTRON-CAPTURE PROCESS AND CARBON-ENHANCED METAL-POOR STARS

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

Hampel, Melanie; Stancliffe, Richard J.; Lugaro, Maria

Carbon-enhanced metal-poor (CEMP) stars in the Galactic Halo display enrichments in heavy elements associated with either the s (slow) or the r (rapid) neutron-capture process (e.g., barium and europium, respectively), and in some cases they display evidence of both. The abundance patterns of these CEMP- s / r stars, which show both Ba and Eu enrichment, are particularly puzzling, since the s and the r processes require neutron densities that are more than ten orders of magnitude apart and, hence, are thought to occur in very different stellar sites with very different physical conditions. We investigate whether the abundance patternsmore » of CEMP- s / r stars can arise from the nucleosynthesis of the intermediate neutron-capture process (the i process), which is characterized by neutron densities between those of the s and the r processes. Using nuclear network calculations, we study neutron capture nucleosynthesis at different constant neutron densities n ranging from 10{sup 7}–10{sup 15} cm{sup -3}. With respect to the classical s process resulting from neutron densities on the lowest side of this range, neutron densities on the highest side result in abundance patterns, which show an increased production of heavy s -process and r -process elements, but similar abundances of the light s -process elements. Such high values of n may occur in the thermal pulses of asymptotic giant branch stars due to proton ingestion episodes. Comparison to the surface abundances of 20 CEMP- s / r stars shows that our modeled i -process abundances successfully reproduce observed abundance patterns, which could not be previously explained by s -process nucleosynthesis. Because the i -process models fit the abundances of CEMP- s / r stars so well, we propose that this class should be renamed as CEMP- i .« less

Interferon induction by and toxicity of polyriboinosinic acid [poly(rI)].polyribocytidylic acid [poly (rC)], mismatched analog poly (rI).poly[r(C12Uracil)n], and poly(rI).poly(rC) L-lysine complexed with carboxymethylcellulose.

PubMed Central

Stringfellow, D A; Weed, S D

1980-01-01

The ability of polyriboinosionic acid [poly(rI)].polyribocytidylic acid [poly(rC)], mismatched analog poly (rI).poly[r(C12Uracil)n], and poly(rI).poly(rC) complexed with poly L-lysine and carboxymethylcellulose [poly(ICLc)] to induce interferon and the comparative toxicity of each in cats were evaluated. Each induced high levels of circulating interferon, although poly(ICLC) injected intravenously at 1 to 4 mg/kg induced up to 10 times more interferon than the other compounds. Each compound was pyrogenic and caused a transient decrease in leukocyte numbers. Poly(rI).poly(rC) and the mismatched analog caused severe diarrhea and nausea at the highest drug concentrations (1 to 4 mg/kg), but poly (ICLC) did not. Each compound also caused depression and lethargy and impaired coordination. PMID:6157363

PaR-PaR Laboratory Automation Platform

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

Linshiz, G; Stawski, N; Poust, S

2013-05-01

Labor-intensive multistep biological tasks, such as the construction and cloning of DNA molecules, are prime candidates for laboratory automation. Flexible and biology-friendly operation of robotic equipment is key to its successful integration in biological laboratories, and the efforts required to operate a robot must be much smaller than the alternative manual lab work. To achieve these goals, a simple high-level biology-friendly robot programming language is needed. We have developed and experimentally validated such a language: Programming a Robot (PaR-PaR). The syntax and compiler for the language are based on computer science principles and a deep understanding of biological workflows. PaR-PaRmore » allows researchers to use liquid-handling robots effectively, enabling experiments that would not have been considered previously. After minimal training, a biologist can independently write complicated protocols for a robot within an hour. Adoption of PaR-PaR as a standard cross-platform language would enable hand-written or software-generated robotic protocols to be shared across laboratories.« less

ACToR Chemical Structure processing using Open Source ChemInformatics Libraries (FutureToxII)

EPA Science Inventory

ACToR (Aggregated Computational Toxicology Resource) is a centralized database repository developed by the National Center for Computational Toxicology (NCCT) at the U.S. Environmental Protection Agency (EPA). Free and open source tools were used to compile toxicity data from ove...

Conservation and diversification of the miR166 family in soybean and potential roles of newly identified miR166s.

PubMed

Li, Xuyan; Xie, Xin; Li, Ji; Cui, Yuhai; Hou, Yanming; Zhai, Lulu; Wang, Xiao; Fu, Yanli; Liu, Ranran; Bian, Shaomin

2017-02-01

microRNA166 (miR166) is a highly conserved family of miRNAs implicated in a wide range of cellular and physiological processes in plants. miR166 family generally comprises multiple miR166 members in plants, which might exhibit functional redundancy and specificity. The soybean miR166 family consists of 21 members according to the miRBase database. However, the evolutionary conservation and functional diversification of miR166 family members in soybean remain poorly understood. We identified five novel miR166s in soybean by data mining approach, thus enlarging the size of miR166 family from 21 to 26 members. Phylogenetic analyses of the 26 miR166s and their precursors indicated that soybean miR166 family exhibited both evolutionary conservation and diversification, and ten pairs of miR166 precursors with high sequence identity were individually grouped into a discrete clade in the phylogenetic tree. The analysis of genomic organization and evolution of MIR166 gene family revealed that eight segmental duplications and four tandem duplications might occur during evolution of the miR166 family in soybean. The cis-elements in promoters of MIR166 family genes and their putative targets pointed to their possible contributions to the functional conservation and diversification. The targets of soybean miR166s were predicted, and the cleavage of ATHB14-LIKE transcript was experimentally validated by RACE PCR. Further, the expression patterns of the five newly identified MIR166s and 12 target genes were examined during seed development and in response to abiotic stresses, which provided important clues for dissecting their functions and isoform specificity. This study enlarged the size of soybean miR166 family from 21 to 26 members, and the 26 soybean miR166s exhibited evolutionary conservation and diversification. These findings have laid a foundation for elucidating functional conservation and diversification of miR166 family members, especially during seed development or

Hu antigen R (HuR) multimerization contributes to glioma disease progression.

PubMed

Filippova, Natalia; Yang, Xiuhua; Ananthan, Subramaniam; Sorochinsky, Anastasia; Hackney, James R; Gentry, Zachery; Bae, Sejong; King, Peter; Nabors, L Burt

2017-10-13

Among primary brain cancers, gliomas are the most deadly and most refractory to current treatment modalities. Previous reports overwhelmingly support the role of the RNA-binding protein Hu antigen R (HuR) as a positive regulator of glioma disease progression. HuR expression is consistently elevated in tumor tissues, and a cytoplasmic localization appears essential for HuR-dependent oncogenic transformation. Here, we report HuR aggregation (multimerization) in glioma and the analysis of this tumor-specific HuR protein multimerization in clinical brain tumor samples. Using a split luciferase assay, a bioluminescence resonance energy transfer technique, and site-directed mutagenesis, we examined the domains involved in HuR multimerization. Results obtained with the combination of the split HuR luciferase assay with the bioluminescence resonance energy transfer technique suggested that multiple (at least three) HuR molecules come together during HuR multimerization in glioma cells. Using these data, we developed a model of HuR multimerization in glioma cells. We also demonstrate that exposing glioma cells to the HuR inhibitor tanshinone group compound 15,16-dihydrotanshinone-I or to the newly identified compound 5 disrupts HuR multimerization modules and reduces tumor cell survival and proliferation. In summary, our findings provide new insights into HuR multimerization in glioma and highlight possible pharmacological approaches for targeting HuR domains involved in cancer cell-specific multimerization.

Rolling Deck to Repository (R2R): Supporting Global Data Access Through the Ocean Data Interoperability Platform (ODIP)

NASA Astrophysics Data System (ADS)

Arko, R. A.; Stocks, K.; Chandler, C. L.; Smith, S. R.; Miller, S. P.; Maffei, A. R.; Glaves, H. M.; Carbotte, S. M.

2013-12-01

(http://vocab.nerc.ac.uk/), is a first step towards wider data discoverability. ● Upgrade existing R2R ISO metadata records to be compatible with the new SeaDataNet II Cruise Summary Report (CSR) profile, and publish the records in a standards-compliant Web portal, built on the GeoNetwork open-source package. ● Develop the future workforce. R2R is enlisting and exposing a group of five students to new informatics technologies and international collaboration. Students are undertaking a coordinated series of projects in 2013 and 2014 at each of the R2R partner institutions, combined with travel to selected meetings where they will engage in the ODIP Workshop process; present results; and exchange ideas with working scientists and software developers in Europe and Australia. Students work closely with staff at the R2R partner institutions, in projects that build on the R2R-ODIP technical work components described above.

Degenerate r-Stirling Numbers and r-Bell Polynomials

NASA Astrophysics Data System (ADS)

Kim, T.; Yao, Y.; Kim, D. S.; Jang, G.-W.

2018-01-01

The purpose of this paper is to exploit umbral calculus in order to derive some properties, recurrence relations, and identities related to the degenerate r-Stirling numbers of the second kind and the degenerate r-Bell polynomials. Especially, we will express the degenerate r-Bell polynomials as linear combinations of many well-known families of special polynomials.

Facilitating hydrological data analysis workflows in R: the RHydro package

NASA Astrophysics Data System (ADS)

Buytaert, Wouter; Moulds, Simon; Skoien, Jon; Pebesma, Edzer; Reusser, Dominik

2015-04-01

The advent of new technologies such as web-services and big data analytics holds great promise for hydrological data analysis and simulation. Driven by the need for better water management tools, it allows for the construction of much more complex workflows, that integrate more and potentially more heterogeneous data sources with longer tool chains of algorithms and models. With the scientific challenge of designing the most adequate processing workflow comes the technical challenge of implementing the workflow with a minimal risk for errors. A wide variety of new workbench technologies and other data handling systems are being developed. At the same time, the functionality of available data processing languages such as R and Python is increasing at an accelerating pace. Because of the large diversity of scientific questions and simulation needs in hydrology, it is unlikely that one single optimal method for constructing hydrological data analysis workflows will emerge. Nevertheless, languages such as R and Python are quickly gaining popularity because they combine a wide array of functionality with high flexibility and versatility. The object-oriented nature of high-level data processing languages makes them particularly suited for the handling of complex and potentially large datasets. In this paper, we explore how handling and processing of hydrological data in R can be facilitated further by designing and implementing a set of relevant classes and methods in the experimental R package RHydro. We build upon existing efforts such as the sp and raster packages for spatial data and the spacetime package for spatiotemporal data to define classes for hydrological data (HydroST). In order to handle simulation data from hydrological models conveniently, a HM class is defined. Relevant methods are implemented to allow for an optimal integration of the HM class with existing model fitting and simulation functionality in R. Lastly, we discuss some of the design challenges

Cyclin-dependent Kinase 9 Links RNA Polymerase II Transcription to Processing of Ribosomal RNA*

PubMed Central

Burger, Kaspar; Mühl, Bastian; Rohrmoser, Michaela; Coordes, Britta; Heidemann, Martin; Kellner, Markus; Gruber-Eber, Anita; Heissmeyer, Vigo; Strässer, Katja; Eick, Dirk

2013-01-01

Ribosome biogenesis is a process required for cellular growth and proliferation. Processing of ribosomal RNA (rRNA) is highly sensitive to flavopiridol, a specific inhibitor of cyclin-dependent kinase 9 (Cdk9). Cdk9 has been characterized as the catalytic subunit of the positive transcription elongation factor b (P-TEFb) of RNA polymerase II (RNAPII). Here we studied the connection between RNAPII transcription and rRNA processing. We show that inhibition of RNAPII activity by α-amanitin specifically blocks processing of rRNA. The block is characterized by accumulation of 3′ extended unprocessed 47 S rRNAs and the entire inhibition of other 47 S rRNA-specific processing steps. The transcription rate of rRNA is moderately reduced after inhibition of Cdk9, suggesting that defective 3′ processing of rRNA negatively feeds back on RNAPI transcription. Knockdown of Cdk9 caused a strong reduction of the levels of RNAPII-transcribed U8 small nucleolar RNA, which is essential for 3′ rRNA processing in mammalian cells. Our data demonstrate a pivotal role of Cdk9 activity for coupling of RNAPII transcription with small nucleolar RNA production and rRNA processing. PMID:23744076

An Adaptive and Time-Efficient ECG R-Peak Detection Algorithm.

PubMed

Qin, Qin; Li, Jianqing; Yue, Yinggao; Liu, Chengyu

2017-01-01

R-peak detection is crucial in electrocardiogram (ECG) signal analysis. This study proposed an adaptive and time-efficient R-peak detection algorithm for ECG processing. First, wavelet multiresolution analysis was applied to enhance the ECG signal representation. Then, ECG was mirrored to convert large negative R-peaks to positive ones. After that, local maximums were calculated by the first-order forward differential approach and were truncated by the amplitude and time interval thresholds to locate the R-peaks. The algorithm performances, including detection accuracy and time consumption, were tested on the MIT-BIH arrhythmia database and the QT database. Experimental results showed that the proposed algorithm achieved mean sensitivity of 99.39%, positive predictivity of 99.49%, and accuracy of 98.89% on the MIT-BIH arrhythmia database and 99.83%, 99.90%, and 99.73%, respectively, on the QT database. By processing one ECG record, the mean time consumptions were 0.872 s and 0.763 s for the MIT-BIH arrhythmia database and QT database, respectively, yielding 30.6% and 32.9% of time reduction compared to the traditional Pan-Tompkins method.

An Adaptive and Time-Efficient ECG R-Peak Detection Algorithm

PubMed Central

Qin, Qin

2017-01-01

R-peak detection is crucial in electrocardiogram (ECG) signal analysis. This study proposed an adaptive and time-efficient R-peak detection algorithm for ECG processing. First, wavelet multiresolution analysis was applied to enhance the ECG signal representation. Then, ECG was mirrored to convert large negative R-peaks to positive ones. After that, local maximums were calculated by the first-order forward differential approach and were truncated by the amplitude and time interval thresholds to locate the R-peaks. The algorithm performances, including detection accuracy and time consumption, were tested on the MIT-BIH arrhythmia database and the QT database. Experimental results showed that the proposed algorithm achieved mean sensitivity of 99.39%, positive predictivity of 99.49%, and accuracy of 98.89% on the MIT-BIH arrhythmia database and 99.83%, 99.90%, and 99.73%, respectively, on the QT database. By processing one ECG record, the mean time consumptions were 0.872 s and 0.763 s for the MIT-BIH arrhythmia database and QT database, respectively, yielding 30.6% and 32.9% of time reduction compared to the traditional Pan-Tompkins method. PMID:29104745

Acetylcholinesterase-R increases germ cell apoptosis but enhances sperm motility

PubMed Central

Mor, I; Sklan, EH; Podoly, E; Pick, M; Kirschner, M; Yogev, L; Bar-Sheshet Itach, S; Schreiber, L; Geyer, B; Mor, T; Grisaru, D; Soreq, H

2008-01-01

Abstract Changes in protein subdomains through alternative splicing often modify protein-protein interactions, altering biological processes. A relevant example is that of the stress-induced up-regulation of the acetylcholinesterase (AChE-R) splice variant, a common response in various tissues. In germ cells of male transgenic TgR mice, AChE-R excess associates with reduced sperm differentiation and sperm counts. To explore the mechanism(s) by which AChE-R up-regulation affects spermatogenesis, we identified AChE-R's protein partners through a yeast two-hybrid screen. In meiotic spermatocytes from TgR mice, we detected AChE-R interaction with the scaffold protein RACK1 and elevated apoptosis. This correlated with reduced scavenging by RACK1 of the pro-apoptotic TAp73, an outcome compatible with the increased apoptosis. In contrast, at later stages in sperm development, AChE-R's interaction with the glycolytic enzyme enolase-α elevates enolase activity. In transfected cells, enforced AChE-R excess increased glucose uptake and adenosine tri-phosphate (ATP) levels. Correspondingly, TgR sperm cells display elevated ATP levels, mitochondrial hyperactivity and increased motility. In human donors' sperm, we found direct association of sperm motility with AChE-R expression. Interchanging interactions with RACK1 and enolase-α may hence enable AChE-R to affect both sperm differentiation and function by participating in independent cellular pathways. PMID:18194455

Molecular design for recombinant adeno-associated virus (rAAV) vector production.

PubMed

Aponte-Ubillus, Juan Jose; Barajas, Daniel; Peltier, Joseph; Bardliving, Cameron; Shamlou, Parviz; Gold, Daniel

2018-02-01

Recombinant adeno-associated virus (rAAV) vectors are increasingly popular tools for gene therapy applications. Their non-pathogenic status, low inflammatory potential, availability of viral serotypes with different tissue tropisms, and prospective long-lasting gene expression are important attributes that make rAAVs safe and efficient therapeutic options. Over the last three decades, several groups have engineered recombinant AAV-producing platforms, yielding high titers of transducing vector particles. Current specific productivity yields from different platforms range from 10 3 to 10 5 vector genomes (vg) per cell, and there is an ongoing effort to improve vector yields in order to satisfy high product demands required for clinical trials and future commercialization.Crucial aspects of vector production include the molecular design of the rAAV-producing host cell line along with the design of AAV genes, promoters, and regulatory elements. Appropriately, configuring and balancing the expression of these elements not only contributes toward high productivity, it also improves process robustness and product quality. In this mini-review, the rational design of rAAV-producing expression systems is discussed, with special attention to molecular strategies that contribute to high-yielding, biomanufacturing-amenable rAAV production processes. Details on molecular optimization from four rAAV expression systems are covered: adenovirus, herpesvirus, and baculovirus complementation systems, as well as a recently explored yeast expression system.