A PETROLOGIC, GEOCHEMICAL AND OSMIUM ISOTOPIC STUDY OF SELECTED PRECAMBRIAN KOMATIITES

The major and trace elements, and Re-Os isotope systematics of the ca. 2.7-Ga komatiites from the Alexo and Dundonald Beach areas in the Abitibi greenstone belt, Canada, and ca. 2.0-Ga komatiites from Jeesiörova, Finnish Lapland were examined in order to constrain the long-term Os isotopic evolution of their mantle sources and also to evaluate different petrogenetic models for their generation. The Re-Os isotope results for whole-rock komatiites and chromite separates from Alexo, Dundonald Beach and the Jeesiörova areas, all yield precisely chondritic intial Os isotopic compositions of their mantle sources (gamma-Os = -0.1± 1.0, 0.0 ± 0.6 and 0.1± 0.5, respectively), consistent with that for the projected primitive upper mantle. The uniform chondritic initial Os isotopic compositions of these komatiites suggest their derivation from mantle sources that had undergone neither long-term Re-depletion nor enrichments in radiogenic Os-187. The uniform chondritic initial Os isotopic compositions of the Ti-rich Finnish komatiites also suggest that the processes responsible for high Ti concentrations in the Finnish rocks must have either been coeval with the generation of the rocks or Re and Os were not significantly fractionated during the processes. The uniform Os isotopic compositions of the Precambrian mantle source regions for these komatiites are in contrast to the variably radiogenic Os isotopic compositions, commonly reported for the present-day ocean island basalts and modern arc-related rocks. This suggests that the Precambrian mantle was significantly more homogeneous than the present-day mantle. Finally, the high-precision Os isotopic results of this study, combined with those previously published for Precambrian ultramafic rocks suggest that although Os isotopic heterogeneities began to appear in the terrestrial mantle as early as ~2.8 Ga, large portions of the Precambrian mantle were evidently not affected by the processes responsible for long-term Os isotopic heterogeneities

EVALUATION OF ANTICANCER ACTIVITY OF ETHANOLIC EXTRACT OF CYPERUS KYLLINGIA ENDL. IN EHRLICH ASCITES CARCINOMA-INDUCED SWISS ALBINO MICE

Objective: The purpose of the study was to evaluate the antitumor and antioxidant status of ethanolic extract of Cyperus kyllingia Endl. on Ehrlich ascites carcinoma (EAC)-treated mice.Methods: The determination of in vivo antitumor activity was performed using EAC cells inoculated mice groups (n=12). The groups were treated for 9 consecutive days with ethanolic extract of C. kyllingia (EECK) at the doses of 20 and 40 mg/kg b.w., respectively. After 24 h of the last dose, half of the mice were sacrificed and the rest were kept alive for assessment of increase in life span. The antitumor potential of EECK was assessed by evaluating tumor volume, viable and non-viable tumor cell count, tumor weight, hematological parameters, and biochemical estimations. Furthermore, antioxidant parameters were assayed by estimating liver tissue enzymes.Results: EECK showed direct cytotoxicity on EAC cell line in a dose-dependent manner. EECK exhibited significant (p<0.05) decrease in the tumor volume, viable cell count, tumor weight, and elevated the life span of EAC tumor-bearing mice. The hematological profile, biochemical estimations, and tissue antioxidant assay were reverted to normal level in EECK-treated mice.Conclusion: Experimental results revealed that EECK possesses potent antitumor and antioxidant properties. Further, research is going on to find out the active principle(s) of EECK for better understanding of mechanism of its antitumor and antioxidant activity

Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration, Contents identical with the version published in Pramana - J. Physic

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

An experimental petrologic study of basalts from selected formations of the deccan traps, India

Crystallization experiments were performed at one-atmosphere pressure and Quartz- Fayalite-Magnetite (QFM) buffer conditions on tholeiitic basalts from Ambenali and Bushe formations of the Deccan Traps. The sequence and chemistry of the experimentally produced phase assernblages are in general agreement with the observed petrographic and geochemical variation of the natural Ambenali samples. When Bushe and Ambenali basalts are plotted on a cpx-ol-qz diagram, Ambenali plots close to the ol+aug+pl+l pseudo-cotectic whereas Bushe basalts define the pigeonite liquidus field which is somewhat different from that inferred by Grove and Bryan (1983) for midoceanic ridge basalts (MORBs). The difference can be ascribed to the different bulk composition of the starting materials used in the present experiments. Although ol → ol+ aug are near liquidus assemblages in the experiments on Neral at QFM, natural samples from this formation are rnostly aphyric. This may indicate that (1) the within-chamber crystal sorting processes were extremely efficient so that the crystals were totally removed from the melt prior to their eruption, or (2) the lavas erupted at super-liquidus temperatures (i.e., carried superheat)

Kinetics of oxidation of iodide ion by <i>trans-</i>(cyclohexane-l ,2-diamine N,N,N',N' tetraacetato)manganate(III) weakly acidic solution

531-533Kinetics of redox reaction between Iˉ and [MnIII(cdta)]ˉ has been investigated in aqueous solution by a stopped-flow technique at pH 3.26 (acetate buffer) and at 30, 35 40 and 45°C. The overall reaction is third order-first order in [MnIII(cdta)ˉ] and second order in [Iˉ]. Though no direct evidence has been obtained, an inner-sphere mechanism has been proposed based on the lability of the complex and is supported by the large negative value of ΔS# (-168 ± 6) JK-1 mol-1

Left subclavian artery stenosis treated with transcatheter stent placement in pediatric patients

Left subclavian artery (LSA) stenosis causing limb length shortening or vascular compromise or significant pulse volume and blood pressure differences between two upper limbs are rarely described in pediatric patients. Here, we are presenting three such cases, two of them were congenital and another one acquired in origin. All of them were successfully treated with transcatheter implantation of stent in LSA. Normalization of limb length was detected on follow-up

Kinetics of electron transfer between bis( 2,2' -bipyridine )manganese(III) complex and thioureas in aqueous perchlorate media

43-46Kinetics of the redox interactions of thiourea and its N-substituted derivatives with manganese(III) complex of 2,2'-bipyridine has been investigated in aqueous solution by a stopped-flow technique in the acid range [H+], 0.10-0.50 mol dm-3 at l= 1.0 mol dm -3 (NaClO4) and at 30°C. A rapid initial increase in absorbance is followed by a slower decay of the formed species for all the four thioureas. Both the reaction steps are analysed and an inner sphere mechanism has been proposed for these reactions. The reactivity order for these thiourea derivatives is: ptu >tu >mtu >atu, and this bears a consequence to their substituent effects

Phytochemical investigation and exploration of CNS depressant efficacy of ethanolic root extract of <em>Cyperus kyllinga </em> Endl.

801-804Sedative drugs such as diazepam, lorazepam, pentoberbitone, amphetamine derivatives etc., are known to have permanent side effects. However, addiction to such drugs, possibly out of depression, is not uncommon. Similar drugs from plant origin with same efficacy could be a better safe alternative. In this study, we evaluated ethanolic extract of roots of the Cyperus kyllinga Endl. (Nut grass) for central nervous system (CNS) depressant activity (sedative activity) at the dose 20 and 40 mg/kg body wt. when administered i.p. The standard drug used was diazepam. The CNS activity was assayed in two experimental models: locomotor activity using actophtometer and skeletal muscle relaxant test by Rota rod apparatus. The ethanolic extract of the C. kyllinga demonstrated depression of the CNS activities in the mice. Phytochemical preliminary screening of the root extract has revealed the presence of flavonoids, carbohydrates, phenolic compounds, steroids and saponin glycoside

[2]Pseudorotaxane Formation with FRET Based Luminescence Response: Demonstration of Boolean Operations through Self-Sorting on Solid Surface

Binary pseudorotaxane formation between an aza crown derivative as host (<b>H</b>) and two different imidazolium derivatives as guests (<b>G</b>_<b>1</b> and <b>G</b>_<b>2</b>) have been studied in detail by NMR (¹H NMR, 2D NOESY), optical (steady state electronic and emission spectroscopy), and mass spectroscopy. Binding stoichiometry (1:1), association constant for the respective [2]­pseudorotaxane formation (<i>K</i>_a^{<b>H.G</b>_<b>1</b>} = (2.61 ± 0.015) × 10³ M^–1 and <i>K</i>_a^{<b>H.G₂</b>} = (1.27 ± 0.16) × 10³ M^–1), and associated thermodynamic parameters are also evaluated based on isothermal titration calorimetric (ITC) studies. FRET based <i>luminescence ON</i> responses are observed on formation of the binary pseudorotaxane (<b>H.G</b>_<b>1</b> and <b>H.G</b>_<b>2</b>) in a nonpolar medium like dichloromethane. The thermodynamic feasibility of such an energy transfer process is also examined. The higher affinity of <b>H</b> and 18-crown-6 toward K⁺, as compared to those toward <b>G</b>_<b>1</b> or <b>G</b>_<b>2</b>, and the reversibility in the host–guest binding process are utilized in demonstrating the self-sorting phenomena with associated changes in luminescence responses that could be correlated for Boolean operators like YES, INHIBIT, OR, and AND gates