Computational Characterization of Astrophysical Species: The Case of Noble Gas Hydride Cations

Theoretical–computational studies together with recent astronomical observations have shown that under extreme conditions in the interstellar medium (ISM), complexes of noble gases may be formed. Such observations have generated a wide range of possibilities. In order to identify new species containing such atoms, the present study gathers spectroscopic data for noble gas hydride cations, NgH+ (Ng = He, Ne, Ar) from high-level ab initio quantum chemistry computations, aiming to contribute in understanding the chemical bonding and electron sharing in these systems. The interaction potentials are obtained from CCSD(T)/CBS and MRCI+Q calculations using large basis sets, and then employed to compute vibrational levels and molecular spectroscopic constants for all known stable isotopologues of ground state NgH+ cations. Comparisons with previously reported values available are discussed, indicating that the present data could serve as a benchmark for future studies on these systems and on higher-order cationic noble gas hydrides of astrophysical interest.

Theoretical study with rovibrational and electronic transitionmoment calculation of the ion LiCs+

10.1139/p06-073 ◽

2006 ◽

Vol 84 (11) ◽

pp. 959-971 ◽

Cited By ~ 8

Author(s):

M Korek ◽

A M Moghrabi ◽

A R Allouche ◽

M Aubert Frécon

Keyword(s):

Internuclear Distance ◽

Bound States ◽

Dipole Moments ◽

Basis Sets ◽

Spectroscopic Constants ◽

Gaussian Basis Sets ◽

Transition Dipole ◽

Vibrational Levels ◽

Moment Functions ◽

Dependent Polarization

For the molecular ion LiCs+ the potential energy are calculated for the 39 lowest molecular states of symmetries 2Σ+, 2Π, 2Δ, and Ω = 1/2, 3/2, 5/2. Using an ab initio method, the calculation is based on nonempirical pseudopotentials and parameterized [Formula: see text]-dependent polarization potentials. Gaussian basis sets are used for both atoms and spin-orbit effects are taken into account. The spectroscopic constants for 20 states are calculated by fitting the calculated energy values to a polynomial in terms of the internuclear distance r. Through the canonical functions approach, the eigenvalue Ev, the abscissas of the corresponding turning points (rmin and rmax), and the rotational constants Bv are calculated for up to 44 vibrational levels for four bound states. Using the same approach the dipole moment functions, the corresponding matrix elements, and the transition dipole moments are calculated for the bound states (1)2Σ+, (2)2Σ+, and (1)2Π. The comparison of the present results with those available in literature for the ground state shows a very good agreement. Extensive tables of energy values versus internuclear distance are displayed at the following address: http://lasim.univ-lyon1.fr/allouche/licsso.html.PACS Nos.: 31.15.Ar, 31.25.–v, 31.25.Nj

General characterization of regeneration in Aeolosoma viride

10.1101/493304 ◽

2018 ◽

Author(s):

Chiao-Ping Chen ◽

Sheridan Ke-Wing Fok ◽

Yu-Wen Hsieh ◽

Cheng-Yi Chen ◽

Fei-Man Hsu ◽

...

Keyword(s):

Cell Proliferation ◽

Model Organisms ◽

Regenerative Processes ◽

Blastema Cell ◽

Microtubule Inhibitor ◽

Wide Range ◽

Highly Correlated ◽

High Level ◽

Complete Regeneration

Regeneration has long attracted scientists for its potential to restore lost, damaged or aged tissues and organs. A wide range of studies have conducted on different model organisms on both cellular and molecular levels. Current evidences suggest that a variety of regenerative strategies are developed and used by different species, and their regenerative strategies are highly correlated to their reproductive methods. Our present work focused on the freshwater annelid Aeolosoma viride, which reproduces by paratonic fission and is capable of complete regeneration. We found out that A. viride can regenerate both anterior and posterior end, even with only 3 segments remained. This process is characterized by epimorphosis that involves large amount of cell proliferation which drives the formation of blastema. Cell proliferation and regeneration successful ratio were significantly decreased when treated with microtubule inhibitor taxol or Avi-tubulin dsRNA, which confirmed that cell proliferation served as a key event during regeneration. Together, our data described the regenerative processes of A. viride, which includes high level of cell proliferation and the formation of blastema. Furthermore, our findings demonstrated A. viride as a potential model for the study of regeneration.

Applied Demography In Action: A Case Study of “Population Identification.”

Canadian Studies in Population ◽

10.25336/p65d0p ◽

2008 ◽

Vol 35 (1) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

David A. Swanson

Keyword(s):

Nuclear Regulatory Commission ◽

Nuclear Waste Repository ◽

Graduate Studies ◽

Wide Range ◽

The Us ◽

High Level Nuclear Waste ◽

Regulatory Commission ◽

This case study deals with a problem quite different than the typical one facing most applied demographers. It involves the identification of a “population” using a set of criteria established by a regulatory agency. Specifically, criteria established by the US Nuclear Regulatory Commission for purposes of Site Characterization of the High Level Nuclear Waste Repository proposed for Yucca Mountain, Nevada. Consistent with other recent studies, this one suggests that a wide range of skills may be needed in dealing with problems posed to applied demographers by clients and users in the 21st century. As such, budding applied demographers, especially those nearing completion of their graduate studies, should consider adopting a set of skills beyond traditional demography.

Characterization of the variability in the O+B eclipsing binary HD 165246

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab488 ◽

2021 ◽

Vol 503 (1) ◽

pp. 1124-1137

Author(s):

C Johnston ◽

N Aimar ◽

M Abdul-Masih ◽

D M Bowman ◽

T R White ◽

...

Keyword(s):

Binary Solution ◽

Rotational Frequency ◽

Primary Component ◽

Data Set ◽

Eclipsing Binary ◽

Photometric Observations ◽

Wide Range ◽

Evolutionary Context ◽

ABSTRACT O-stars are known to experience a wide range of variability mechanisms originating at both their surface and their near-core regions. Characterization and understanding of this variability and its potential causes are integral for evolutionary calculations. We use a new extensive high-resolution spectroscopic data set to characterize the variability observed in both the spectroscopic and space-based photometric observations of the O+B eclipsing binary HD 165246. We present an updated atmospheric and binary solution for the primary component, involving a high level of microturbulence ($13_{-1.3}^{+1.0}\,$ km s−1) and a mass of $M_1=23.7_{-1.4}^{+1.1}$ M⊙, placing it in a sparsely explored region of the Hertzsprung--Russell diagram. Furthermore, we deduce a rotational frequency of $0.690\pm 0.003\,$d−1 from the combined photometric and line-profile variability, implying that the primary rotates at 40 per cent of its critical Keplerian rotation rate. We discuss the potential explanations for the overall variability observed in this massive binary, and discuss its evolutionary context.

Characterization of the shallow state of iodine chloride

10.1139/p84-238 ◽

1984 ◽

Vol 62 (12) ◽

pp. 1947-1953 ◽

Cited By ~ 13

Author(s):

J. C. D. Brand ◽

D. Bussières ◽

A. R. Hoy ◽

S. M. Jaywant

Keyword(s):

Ground State ◽

Spectroscopic Constants ◽

Interaction Matrix ◽

Electronic Interaction ◽

Weakly Bound ◽

Interaction Matrix Element ◽

Vibrational Levels ◽

State 1 ◽

Shallow State

A weakly bound Ω = 1 state of ICl, [Formula: see text], which converges to the ground state 1(2P3/2) + Cl(2P3/2) of the separated atoms, has been identified and characterized. Spectroscopic constants of this state are Te = 17 338.0(13), ωe = 32.85(48), ωexe = 1.272(40), 103Be = 38.2(13), 104αe = 8.89(34), 105γe = −8.1(20) cm−1, and re = 4.01(6) Å. The dissociation energy De = 219.6 cm−1 is consistent with the value predicted for a Morse function, [Formula: see text]. Transitions [Formula: see text] are allowed owing to homogeneous coupling between ã and the well-defined A(3π1) state; in fact, at medium-long range (r = 6–6.5 Å, D–Gν = 20–30 cm−1), the diabatic ã and A curves cross at a small angle. Principal features of the crossing are explained if the electronic interaction matrix element is ca. 4 cm−1, corresponding to weak coupling. Heterogeneous perturbations of the A and ã states in the range D–Gν < 200 cm−1 are attributed to coupling with high vibrational levels of the ground state X(1Σ+).

Potential curves and rovibrational energies for electronic states of the molecular ion KCs+

10.1139/p02-045 ◽

2002 ◽

Vol 80 (9) ◽

pp. 1025-1035 ◽

Cited By ~ 16

Author(s):

M Korek ◽

A R Allouche ◽

S N Abdul Al

Keyword(s):

Internuclear Distance ◽

Bound States ◽

Electronic States ◽

Oscillator Strengths ◽

Basis Sets ◽

Spectroscopic Constants ◽

Spin Orbit ◽

Molecular Ion ◽

Wide Range ◽

Potential Curves

The KCs+ molecular ion potential curves are investigated over a wide range of internuclear distance for electronic states described in a 2Λ(+) representation (neglecting the spin-orbit effect) as well as in an Ω(+) representation (including the spin-orbit effect). This calculation has been done in a one active electron approach by using an ab initio method based on non-empirical pseudopotentials with core-valence effect taken into account through parameterized l-dependent polarization potentials. Gaussian basis sets have been used for both atoms, and spin-orbit effects have been taken into account through a semiempirical spin-orbit pseudopotential. The canonical functions approach is used to do a rovibrational study by calculating the eigenvalues Ev, the rotational constant Bv, the centrifugal distortion constants Dv (up to 106 vibrational levels), and the spectroscopic constants are deduced for six bound states. The permanent and transition dipole moment functions have been derived for transitions between the bound states 2 Σ+ and 2Π as well as the oscillator strengths for the transitions v = 0, 10, 20, and Δ v = 0, 1, 2, ..., 6. To the best of our knowledge neither theoretical nor experimental data are available in the literature for the molecular ion KCs+. Extensive tables of Ev, Bv, Dv, and the energy values versus internuclear distance are displayed at the following address: http://hplasim2.univ-lyon1.fr/allouche/kcsplus.html. PACS Nos.: 33.15Dj, 33.20wr

Improved Spectroscopic Data Synthesis for I2(B3ΠOu+) and Predictions of J Dependence for B(3ΠOu+)–X(1Σg+) Transition Intensities

10.1139/p73-220 ◽

1973 ◽

Vol 51 (15) ◽

pp. 1664-1677 ◽

Cited By ~ 40

Author(s):

J. David Brown ◽

George Burns ◽

Robert J. Le Roy

Keyword(s):

Spectroscopic Data ◽

Population Distribution ◽

Intermolecular Potential ◽

Molecular Constants ◽

Wide Range ◽

Vibrational Levels ◽

Condon Factors ◽

Vibrational Bands ◽

Franck Condon

Some new techniques are introduced in a reanalysis of the spectroscopic data for I2(B3ΠOu+)to obtain a more complete and internally consistent set of molecular constants, and an RKR potential curve. In particular, attention is focussed on the determination of reliable high-order rotational constants (Dν, Hν, etc.) for highly excited vibrational levels. The ensuing intermolecular potential for this state is then used together with a known ground-state curve in a study of the J dependence of Franck-Condon factors for discrete B(3ΠOu+)–X(1Σg+) transitions over a wide range of ν and J. It is concluded that at the temperatures 1000–2000 °K routinely achieved in shock-tube experiments, the intensity of most vibrational bands will vary drastically as J ranges across the half-width of the thermal rotational population distribution.

Purification and characterization of cytosolic and microsomal cyclophilins from maize (Zea mays)

Biochemical Journal ◽

10.1042/bj3150965 ◽

1996 ◽

Vol 315 (3) ◽

pp. 965-970 ◽

Cited By ~ 14

Author(s):

Philip S. SHELDON ◽

Michael A. VENIS

Keyword(s):

Cyclosporin A ◽

Sequence Similarity ◽

Terminal Sequence ◽

Purification And Characterization ◽

Cyclophilin B ◽

Sds Page ◽

Wide Range ◽

Molecular Masses ◽

Methods for the purification and separation of peptidyl prolyl cis–trans isomerase (PPI) from cytosolic and microsomal fractions of etiolated maize are described. On SDS/PAGE, the purified preparations appear as single polypeptides with molecular masses of 17.5 kDa and 17.7 kDa respectively. Instead of using immobilized cyclosporin A derivatives as affinity adsorbents, our methods employ conventional techniques enabling purification of the proteins on a much larger scale than previously described. An antiserum raised against the cytosolic PPI recognizes polypeptides of similar molecular mass from a wide range of plant species on an immunoblot. There is virtually no recognition of the microsomal PPI. The cytosolic and microsomal PPIs are inhibited by cyclosporin A (Ki = 6 nM in both cases), indicating that they are cyclophilins. The cytosolic enzyme is inactivated by 5 mM N-ethylmaleimide and 2 mM phenylglyoxal. N-terminal sequencing of the microsomal PPI indicates a high level of sequence similarity with the N-terminal sequence of mature animal s-cyclophilin (cyclophilin B).

Isolation and Biochemical Characterization of Two Novel Metagenome-Derived Esterases

Applied and Environmental Microbiology ◽

10.1128/aem.72.5.3637-3645.2006 ◽

2006 ◽

Vol 72 (5) ◽

pp. 3637-3645 ◽

Cited By ~ 126

Author(s):

C. Elend ◽

C. Schmeisser ◽

C. Leggewie ◽

P. Babiak ◽

J. D. Carballeira ◽

...

Keyword(s):

Biochemical Characterization ◽

Biotechnological Applications ◽

Temperature Optimum ◽

Ph Optimum ◽

Level Of Activity ◽

Wide Range ◽

Soil Metagenome ◽

Ph Range ◽

ABSTRACT The metagenomes of uncultured microbial communities are rich sources for novel biocatalysts. In this study, esterase EstA3 was derived from a drinking water metagenome, and esterase EstCE1 was derived from a soil metagenome. Both esterases are approximately 380 amino acids in size and show similarity to β-lactamases, indicating that they belong to family VIII of the lipases/esterases. EstA3 had a temperature optimum at 50ï¿½C and a pH optimum at pH 9.0. It was remarkably active and very stable in the presence of solvents and over a wide temperature and pH range. It is active in a multimeric form and displayed a high level of activity against a wide range of substrates including one secondary ester, 7-[3-octylcarboxy-(3-hydroxy-3-methyl-butyloxy)]-coumarin, which is normally unreactive. EstCE1 was active in the monomeric form and had a temperature optimum at 47ï¿½C and a pH optimum at pH 10. It exhibited the same level of stability as EstA3 over wide temperature and pH ranges and in the presence of dimethyl sulfoxide, isopropanol, and methanol. EstCE1 was highly enantioselective for (+)-menthylacetate. These enzymes display remarkable characteristics that cannot be related to the original environment from which they were derived. The high level of stability of these enzymes together with their unique substrate specificities make them highly useful for biotechnological applications.