Length–weight relationship for three estuarine fish species from the Chilika Lagoon, India

501-502We investigated the length–weight relationships (LWRs) for Sillago vincenti McKay, 1980, Triacanthus nieuhofii Bleeker, 1852 and Terapon puta Cuvier, 1829 from the Chilika lagoon in India. Sampling was conducted in central sector of the Chilika from April to November of 2017. Specimens were caught in mono-filament gill nets of mesh size 28-36 mm and fixed set nets of mesh size 16-24 mm. From LWR estimation, the determined intercept (a value) and slope (b value) were found to be 0.007 and 3.039 for Sillago vincenti, 0.010 and 2.997 for Triacanthus nieuhofii and 0.008 and 3.156 for Terapon puta. The relationships between length and weight in all three species were highly correlated (p <0.05)

Annals of Library and Information Studies, 2002–2010: A Bibliometric Study

Introduction Research publications are the embodiments of the intellectual thought contents expressed in published literature whose key objective is to transmit innovative ideas or information to any specific field of knowledge towards the further development of a subject or a discipline. In this respect bibliometric study is regarded as one of the crucial areas of research in the field of Library and Information Science. Moreover, bibliometrics study is used as an instrument in the collection building policy by providing the precise and much needed information to the managers to take the right decision in right time as to what documents they should select and what documents they should discard from the existing collections of their respective libraries. Contextually, the present study attempts to measure the publication traits of a premier Indian referred journal namely, Annals of Library and Information Studies (ALIS) from 2002 to 2010. ALIS is a leading library science journal being published by The National Institute of Science Communication and Information Resources (NISCAIR), New Delhi on quarterly basis. This journal publishes articles, documentation notes and research reviews on library, documentation and information science, information systems, services and products, information technology, information users, bibliometrics, scientometrics and informetrics, education and training and other related topics (www.niscair.res.in). Therefore a bibliometric study of this journal is of immense significance. Review of Literature Though the statistics was applied to study the literature in any subject but the first recorded study of Bibliometric topic was in 1917 by Coles and Eales (1917) with the title \u27Statistical analysis of literature of history of comparative anatomy\u27 which served as a model for applying the counting technique in the evaluation of international activities. Pritchard (1969) first introduced the term \u27Bibliometrics\u27 in 1969 to mean \u27the application of mathematics and statistical methods to books and other media of communications\u27. Roy (1983) has defined bibliometrics as a \u27study of the process of information use by analyzing the characteristics of documents and their distribution by statistical methods. Mote and Deshmukh (1996) in their study on Annals of Library Science and Documentation found that journals are most cited form of communication amongst the library and information scientists and the source journal is the most cited publication. Shokeen and Kaushik (2004) in their study on Indian Journal of Plant Physiology found that journal articles are predominant with 81% of total citations. The ratio of author self citation to total citations is 1:16.65. The ratio of Journal Self Citation to total citation is 1:31.91. The results also highlight that 398 citations are below 10 years old, whereas 358 citations are below 20 years but more than 10 years old. In the aforesaid direction, Jena (2007) in his study on Indian Journal of Fibre and Textile Research, 1996–2004\u27 revealed various details of the trend of publications of this journal. Biswas, Roy and Sen (2007) conducted a bibliometric study on Economic Botany from 1994-2003 and revealed that among the citations, books accounted for 59%, journals 41% while, e-citations were quite negligible. Furthermore, they found that the highest numbers of contributions were emanated from academic institutions such as universities. Zao, et al.(2007) in their study on Educational Psychology identified six clusters of journals, including general educational psychology/learning/literacy, school psychology, measurement and counseling, Germany-based educational psychology, creativity, and the other related themes. Furthermore, the study revealed that a small number of journals accounted for a relatively high percentage of the intra-disciplinary citations; the majority of the selected journals cited more than being cited in the field. Turk (2008)indicated that there is quite a uniform way about methodology of citation counts and substantial research about motivation for URL citations to LIS articles. Willet (2008) found that many of the most cited papers in the Journal of Chemical Information and Modeling describe software packages that play a key role in modern chemoinformatics research. Zainab, Ani and Anur (2009) in their bibliometric study on Malayasian Journal of Computer Science evaluated the article productivity of the journal from 1985 to 2007 using Lotka\u27s Law. The study further revealed authorship, co-authorship pattern by degree of authors\u27 collaboration that ranged from 0.25 to 0.95. Asha and Anil (2010) under took a bibliometric study of 4798 citations appended to 400 articles in five volumes (2003-2007) of the Indian Journal of Pure and Applied Mathematics and found that the most cited documents are articles from research journals and the foreign authors have contributed more than Indian authors. Swain (2011) in his scientometric analysis of Library Philosophy and Practice from 2004 to 2009 found that the degree of collaboration in LPP ranged from 0.222 to 0.52 and the highest numbers of contributors hailed from Nigeria, followed by USA, India, and Iran. Swain and Panda (2012) conducted a bibliometric study on Journal of Intellectual Property Rights, 2002 to 2010 and found that due to absolute domination of solo contributions, the visibility of collaborative contribution was found remarkably less. The study further revealed that about one third of the total publications received citations, more than half of the cited articles carried just one citation, one fourth got 2 citations, and the rest received citations between 3 to 9 times. Jena, Swain and Sahu (2012) in their bibliometric study of The Electronic Library from 2003 to 2009 revealed some interesting bibliometric traits of this journal. Taking the above mentioned literature into context, the present study aims to provide some value addition to the corpus of literature on bibliometric studies

Relativistic-coupled-cluster-theory analysis of properties of Co-like ions

Ionization potentials, excitation energies, transition properties, and hyperfine structure constants of the low-lying 3p63d9 2D5/2, 3p63d9 2D3/2, 3p53d10 2P3/2, and 3p53d10 2P1/2 atomic states of the Co-like highly charged ions such as Y12+, Zr13+, Nb14+, Mo15+, Tc16+, Ru17+, Rh18+, Pd19+, Ag20+, and Cd21+ are investigated. The singles and doubles approximated relativistic coupled-cluster theory in the framework of one electron removal Fock-space formalism is employed over the Dirac-Hartree-Fock calculations to account for the electron correlation effects for determining the aforementioned properties. Higher-order relativistic corrections due to the Breit interaction and quantum electrodynamics effects in the evaluation of energies are also quantified explicitly. Our estimated values are compared with the other available theoretical calculations and experimental results, which are found to be in good agreement with each other.11Nsciescopu

Forbidden transition properties in the ground-state configurations of singly ionized noble gas atoms for stellar and interstellar media

High-accuracy calculations of the forbidden transition amplitudes for the np 2P1/2 → np 2P3/2 transitions with the ground-state principal quantum number n in singly charged inert gas atoms, which are of astrophysical interest, have been carried out using sophisticated relativistic many-body methods. Using these amplitudes, the line strengths, oscillator strengths and transition probabilities of the above transitions and lifetimes of the np 2P1/2 states are estimated precisely. Most of these transition wavelengths lie in the infrared region, while the corresponding Rn ii line is the optical one, and they can be observed in the stellar and interstellar media, where the abundances of these ions have already been identified. The above forbidden transitions can also be very useful for astrophysical plasma diagnostics and can guide experiments to measure the lifetimes of the above np 2P1/2 states.by D.K. Nandy and B.K. Saho

Relativistic calculations of radiative properties and fine structure constant varying sensitivity coefficients in the astrophysically relevant Zn II, Si IV and Ti IV ions

We have carried out calculations of the relativistic sensitivity coefficients, oscillator strengths, transition probabilities, lifetimes and magnetic dipole hyperfine structure constants for a number of low-lying states in the Zn ii, Si iv and Ti iv ions which are abundant in the distant quasars and various stellar plasmas. These spectroscopic data will be very useful for probing temporal variation of the fine structure constant (αe) and in the diagnostic processes of some of the astrophysical plasmas. We have employed all-order perturbative methods in the relativistic coupled-cluster framework using the Dirac–Coulomb Hamiltonian to calculate the atomic wavefunctions of the considered ions. Reference states are constructed with the VN−1 and VN+1 potentials and then the electron–electron correlation effects are taken into account by constructing all possible singly and doubly excited configurations, involving both the core and valence electrons, from the respective reference states. We have also determined one electron affinities and ionization potentials of many excited states in these Zn ii, Si iv and Ti iv ions. Except for a few states we have attained accuracies within 1 per cent for the energies compared with their experimental values. Our calculated sensitivity coefficients are estimated to have similar accuracies as of the calculated energies. Furthermore, combining our calculated transition matrix elements with the experimental wavelengths we evaluate transition probabilities, oscillator strengths and lifetimes of some of the excited states in these ions. These results are compared with the available data in a few cases and found to be in very good agreement among themselves. Using our reported hyperfine structure constants due to the dominant magnetic dipole interaction, it is possible to determine hyperfine splittings approximately in the above considered ions.by D.K. Nandy and B.K Saho

Quadrupole shifts for the Yb + 171 ion clocks: Experiments versus theories

[4f146s]2S1/2→[4f145d]2D3/2,[4f146s]2S1/2→[4f145d]2D5/2, and [4f146s]2S1/2→[4f136s2]2F7/2, in the Yb+ ion are investigated by calculating values of the quadrupole moment (Θ) for the 5d3/2,5/2 and 4f7/2 states using the relativistic coupled-cluster (RCC) methods. We find an order of magnitude difference in the Θ value of the 4f7/2 state between our calculation and the experimental result, but our result concurs with that of other calculations carried out using many-body methods different from ours. However, our Θ value of the 5d3/2 state is in good agreement with the available experimental result and is highly precise. This enables us to estimate the quadrupole shift of the [4f146s]2S1/2→[4f145d]2D3/2 clock transition more accurately. To justify the accuracies in our calculations, we evaluate the hyperfine structure constants of the 6s1/2,5d3/2,5/2, and 4f7/2,5/2 states of the Yb+171 ion using the same RCC methods and compare the results with the experimental values. We also determine the lifetime of the 5d3/2 state to address a discrepancy between conflicting values given by recent experiments.D.K. Nandy and B.K. Saho

Quadrupole shifts for the 171Yb+ ion clocks: experiments versus theories

Quadrupole shifts for three prominent clock transitions, [4f146s]2S1/2→[4f145d]2D3/2, [4f146s]2S1/2→[4f145d]2D5/2 and [4f146s]2S1/2→[4f136s2]2F7/2, in the Yb+ ion are investigated by calculating quadrupole moments (Θs) of the 5d3/2,5/2 and 4f7/2 states using the relativistic coupled-cluster (RCC) methods. We find an order difference in the Θ value of the 4f7/2 state between our calculation and the experimental result, but our result concur with the other calculations that are carried out using different many-body methods than ours. Nevertheless, our Θ value of the 5d3/2 state is in good agreement with the available experimental result and becomes more precise till date estimating the quadrupole shift of the [4f146s]2S1/2→[4f145d]2D3/2 clock transition more accurately. To justify accuracies in our calculations, we also evaluate the hyperfine structure constants of the 6s1/2, 5d3/2,5/2 and 4f7/2,5/2 states of 171Yb+ ion using the same RCC method and compare the results with their experimental values. Moreover, we determine lifetime of the 5d3/2 state to eradicate disagreement on its value from two different experiments

Radiative properties of few F- and Cl- like alkali and alkaline-earth metal ions

We present high-accuracy calculations of radiative properties such as oscillator strengths and transition probabilities, of the allowed ns 2S1/2 → np 2P1/2, 3/2 transitions and of the forbidden np 2P1/2 → np 2P3/2 transitions in the F- and Cl-like alkali and alkaline-earth ions with the ground state principal quantum number n of the respective ion. For this purpose, we have employed the Dirac–Fock, relativistic second-order many-body perturbation theory and an all-order perturbative relativistic method in the coupled-cluster (CC) theory framework. To test the validity of these methods for giving accurate results, we first evaluated the ionization potentials in the creation processes of these ions and compare them with their experimental values listed in the National Institute of Science and Technology data base. Moreover, both the allowed and forbidden transition amplitudes are estimated using the above three methods and a comparative analysis is made to follow-up the electron correlation trends in order to demonstrate the need of using a sophisticated method like the CC theory for their precise determination. For astrophysical use, we provide the most precise values of the transition properties by combining the experimental energies, which suppresses uncertainties from the calculated energies, using the transition amplitudes from the CC method. These data will be useful in the abundance analysis of the considered ions in the astronomical objects and for the diagnostic processes of astrophysical plasmas.by D.K. Nandy, Sukhjit Singh and B. K. Saho