2009

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SEM-EDX analysis of various sizes aerosols in Delhi India
(2009) Arun Srivastava; V.K. Jain; Anchal Srivastava
Scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) was used to understand the differences in morphology, elemental composition and particle density of aerosols in different five size ranges to further investigate the potential sources as well as transport of pollutants from/at a much polluted and a very clean area of Delhi. Aerosol samples were obtained in five different size ranges viz. ≥10.9, 10.9-5.4, 5.4-1.6, 1.6-0.7 and ≤0.7 μm from a considerably very clean and a much polluted area of Delhi. It was observed that at polluted area most of the particles irrespective of size are of anthropogenic origin. At clean area, in coarse size fractions particles are of natural origin while in fine size range the presence of anthropogenic particles suggests the transport of particles from one area to the other. © Springer Science+Business Media B.V. 2008.
Influence of temperature on intratrack processes and Ps formation and behaviour in liquid water
(Trans Tech Publications Ltd, 2009) S.V. Stepanov; G. Duplâtre; V.M. Byakov; V.S. Subrahmanyam; D.S. Zvezhinskii; A.S. Mishagina
Positron annihilation lifetime (PAL) spectra are measured in liquid water in the temperature range 2 - 930C. The spectra are treated by taking into account intratrack reactions and assuming that radical reactions with Ps are diffusion-controlled (the respective temperature dependences obeying the Stokes-Einstein law). Equilibrium Ps bubble parameters are obtained. © (2009) Trans Tech Publications, Switzerland.
A novel approach to the interpretation of PAL spectra in glycerol
(Trans Tech Publications Ltd, 2009) S.V. Stepanov; D.S. Zvezhinskii; G. Duplatre; V.M. Byakov; V.S. Subrahmanyam
A new strategy for the treatment of positron annihilation lifetime (PAL) spectra in viscous liquids is proposed, enabling to extract values of the Ps reaction rate constants with intratrack radiolytic products as well as parameters of the free volume distribution in viscous media. © (2009) Trans Tech Publications, Switzerland.
Macrosegregation during directional solidification of Pb-Sb alloys
(Indian Institute of Metals, 2009) S.N. Ojha; S.N. Tewari
Macrosegregation of Sb was investigated during directional solidification of binary Pb-Sb alloys containing 2.2 and 5.8 wt% Sb over growth rates varying from 0.8 to 30 μm s-1. The cellular to dendritic transition was observed at a growth rate of 3.0 μm s-1 in Pb-2.2 Sb alloy in contrast to a growth rate of 1.5 μm s-1 in Pb-5.8 Sb alloy. The chemical analysis data revealed considerable macrosegregation of Sb along the longitudinal section of alloys. The degree of macrosegregation increased with a decrease in the growth rate. This behavior is discussed in light of thermo-solutal convection in the mushy zone as well as that in the melt ahead of the solid-liquid interface. © 2009 TIIM, India.
Some observations on a maturity model for CBSE
(Institute of Electrical and Electronics Engineers Inc., 2009) A.K. Tripathi; Ratneshwer
The Capability Maturity Model (proposed by SEI-CMU) does not consider Component Based Software Engineering (CBSE) principles in its considerations of levels and KPAs. It is therefore necessary to consider a model that is based on peculiarities and importance of CBSE and hence a new model under the name ICMM (Integrated Component Maturity Model) for this purpose is being proposed herein. The model, ICMM, is applicable for many types of organizations like organizations that develop components only, organizations that develop CBS or organizations that develop components along with CBS. This work starts a discussion and calls for more extensive research oriented studies by professionals and academicians for perfection of the model. © 2009 IEEE.
Agent-based computational modeling of emergent collective intelligence
(Springer Verlag, 2009) Vivek Kumar Singh; Divya Gautam; Rishi Raj Singh; Ashok K. Gupta
Collective Intelligence is a form of intelligence which emerges out of collaboration and coordination of many individual agents. A group of actors performing simple behaviours and interacting with fellow group members & the environment often produce global behaviours which seems intelligent. Understanding the emergence of intelligent collective behaviours in social systems, such as norms & conventions, higher level organizations, collective wisdom and evolution of culture from simple and predictable local interactions; has been an important research question since decades. Agent-based modeling of complex social behaviours by simulating social units as agents and modeling their interactions; provides a new generative approach to understanding the dynamics of emergence of collective intelligence behaviours. In this paper, we have presented an analytical account of nature, form and dynamics of collective intelligence, followed by some of our experimental work on evolution of collective intelligence. The paper concludes with a short discussion of the results and relevant implications for designing systems for achieving desired collective intelligence. © 2009 Springer Berlin Heidelberg.
Antibodies to dynorphin A (1-17) attenuate closed head injury induced blood-brain barrier disruption, brain edema formation and brain pathology in the rat
(Springer-Verlag Wien, 2009) H.S. Sharma; R. Patnaik; S. Patnaik; A. Sharma; S. Mohanty; P. Vannemreddy
The potential neuroprotective efficacy of dynorphin A antiserum on BBB dysfunction, edema formation and brain pathology was examined in a closed head injury (CHI) model in the rat. The CHI was produced by an impact of 0.224 N on the right parietal bone under anesthesia by dropping a weight of 114.6 g on the skull from a height of 20 cm through a guide tube. This concussive brain injury resulted in profound BBB disruption as evidenced by leakage of Evans blue and radioiodine in the brain. Edema formation and swelling at 5 h were most pronounced in the contralateral cerebral hemisphere. Pretreatment with dynorphin A antiserum (1:20, monoclonal) infused into the left lateral cerebral ventricle (30 μL in PBS) either 30 min before or 30 min after CHI significantly attenuated BBB dysfunction, brain edema formation, volume swelling and brain pathology. However, no reduction in brain edema, BBB permeability or improved brain pathology was seen when the antiserum was given 60 min post-CHI. These observations are the first to suggest that antiserum to dynorphin when administered into the CSF during early phase of CHI is neuroprotective. Our work further indicates that dynorphin is actively involved in the cellular and molecular mechanisms of edema formation and BBB breakdown in CHI. © 2009 Springer-Verlag Vienna.
Assessment of support capacity requirement for longwall working under difficult caving strata conditions
(International Society for Rock Mechanics, 2009) G.S.P. Singh; U.K. Singh
Reliable assessment of caving behavior of strata and support capacity requirement has been an issue of great demand for reducing the strata control risk while planning of longwall workings specially in difficult to cave strata conditions. This paper describes the findings of an integrated modeling approach for assessment of roof cavability and estimation of optimal support capacity for longwall workings in a given geo-mining condition. A numerical modeling approach is described for assessing the progressive caving behavior of strata and performance of a hydraulic powered roof support in a given geo-mining and strata condition. The modeling approach for support selection is suggested for regular as well as en masse caving conditions integrating the results of numerical modeling and field observation of 23 longwall panels worked in different coalfields of India. A mathematical approach is used to assess the effect of dynamic loading due to en masse caving and to estimate the design requirement of rapid yield valve. The modeling results of a case study of Churcha mine, a mining site well known for its difficult caving strata characteristics in Sonhat coalfield of India is also described. © ISRM International Symposium on Rock Mechanics, SINOROCK 2009.
Role of wave impedance in the formation of photonic band gaps in one-dimensional magnetic star wave guide structure
(IEEE Computer Society, 2009) Sanjeev K. Srivastava; S.K. Srivastava; S.P. Ojha
The present paper describes the study of reflection properties and role of wave impedance in the formation of photonic band gaps in one-dimensional magnetic star waveguide structure (MSWG). From the analysis of the dispersion characteristics, it is found that in magnetic SWG structure existence of band gaps does not require the contrast in the wave impedance of the constituent materials whereas the contrast in wave impedance is must for the existence of band gap in normal magnetic photonic crystal (MPC) structure. Moreover, magnetic SWG structures show wider photonic band gaps in comparison to normal magnetic PC structure for the same contrast in the wave impedance.
2.45 GHz low level CW microwave radiation affects embryo implantation sites and single strand DNA damage in brain cells of mice, mus musculus
(IEEE Computer Society, 2009) Vineet Prakash Singh; Priyanka Singh; Chandra Mohini Chaturvedi; Ritesh K. Shukla; Alok Dhawan; Ravi Kumar Gangwar; Surya Pal Singh
To study the effect of microwave radiation on the early stages of pregnancy (implantation) and DNA damage in brain cells, female mice were exposed to 2.45 GHz electromagnetic field (EMF) for 2 hours/ day at power density of 0.1250 mW/cm2 for the period of 30 days (pre-mating period, 22 days; mating period, 5 days; post mating period, 3 days). The results indicate asymmetrical implantation in the two horns of the uterus in addition to alteration in embryo positioning and altered embryo spacing in exposed mice as compared to control. The microwave radiation also induced significant DNA break in brain cells. Our findings point towards microwave radiation induced adverse effects on early embryonic development (implantation) as well as increased DNA damage in brain cells, although further studies are required to understand the extent and the mechanism of these effects. In view of the increased use of microwaves in the modern society and MW induced pathogenesis reported earlier as well as in the present study, it is necessary to define the safer use and threshold limit of the non-ionizing radiation in terms of its biological effects.

2009

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