High frequency plant regeneration from shoot tip explants of Citrullus colocynthis (Linn.) Schrad. – An important medicinal herb

A high frequency and rapid regeneration protocol was developed from shoot tip explants of Citrullus colocynthis on Murashige and Skoog (MS) medium supplemented with N6-benzylamino-purine (BAP, 0.5 mg/l) and α-naphthalene acetic acid (NAA, 0.5 mg/l). Highest number of shoots (23.0 ± 0.567) was obtained on MS medium containing BAP (0.5 mg/l) and NAA (0.5 mg/l). The regenerated shoots were further elongated on same medium. In vitro shoots were excised from shoot clumps and transferred to rooting medium containing indole-3-butyric acid (IBA, 4.0 mg/l) with 0.2% activated charcoal. The rooted plants were hardened in polycups containing sterile soil and vermiculite and finally well established in the field; survival rate was 60%. This is the first report of direct in vitro plantlet regeneration in C. colocynthis from shoot tip explant.Key words: Citrullus colocynthis, regeneration, shoot tip

Electrical and Magnetic behaviour of PrFeAsO0.8F0.2 superconductor

The superconducting and ground state samples of PrFeAsO0.8F0.2 and PrFeAsO have been synthesised via easy and versatile single step solid state reaction route. X-ray & Reitveld refine parameters of the synthesised samples are in good agreement to the earlier reported value of the structure. The ground state of the pristine compound (PrFeAsO) exhibited a metallic like step in resistivity below 150K followed by another step at 12K. The former is associated with the spin density wave (SDW) like ordering of Fe spins and later to the anomalous magnetic ordering for Pr moments. Both the resistivity anomalies are absent in case of superconducting PrFeAsO0.8F0.2 sample. Detailed high field (up to 12Tesla) electrical and magnetization measurements are carried out for superconducting PrFeAsO0.8F0.2 sample. The PrFeAsO0.8F0.2 exhibited superconducting onset (Tconset) at around 47K with Tc({\rho} =0) at 38K. Though the Tconset remains nearly invariant, the Tc({\rho} =0) is decreased with applied field, and the same is around 23K under applied field of 12Tesla. The upper critical field (Hc2) is estimated from the Ginzburg Landau equation (GL) fitting, which is found to be ~ 182Tesla. Critical current density (Jc) being calculated from high field isothermal magnetization (MH) loops with the help of Beans critical state model, is found to be of the order of 103 A/cm2. Summarily, the superconductivity characterization of single step synthesised PrFeAsO0.8F0.2 superconductor is presented.Comment: 15 Pages Text + Fig

Universal screening for hypothyroidism in pregnancy: is it necessary?

Background: Thyroid diseases are one of the commonest endocrine disorders affecting women of reproductive age group, and hence constitute one important disorders complicating pregnancy. The objective of this study was to determine the importance of universal screening for hypothyroidism in pregnancy at the first antenatal visit and to formulate whether this routine screening is mandatory in our country.Methods: This retrospective study was conducted in the year 2018 at PSG IMSR Hospital for all pregnant women who attended the first antenatal visit between Jan 2012 to Dec 2012 after obtaining ethical clearance. Pregnant women who were already taking treatment for hypothyroidism, diabetes mellitus, hypertension and those pregnant women who lost their follow up were excluded from the study.Results: The incidence of subclinical hypothyroidism among antenatal women were 7.06%. In our study the maternal complications like anemia 12 (8%), preeclampsia 26 (17.3%), gestational diabetes 25 (16.7%), fetal growth restriction 8 (5.3%), Oligohydramnios 13 (8.7%), pre mature rupture of membranes 25 (16.7%), placental abruption in 2 (1.33%), APLA syndrome 2 (1.33%), low birth weight 26 (17.3%) were observed.Conclusions: Universal screening for hypothyroidism is recommended for all antenatal women especially in iodine depleted country like India

Small space analogues of Valiant\u27s classes and the limitations of skew formula

In the uniform circuit model of computation, the width of a boolean circuit exactly characterises the ``space\u27\u27 complexity of the computed function. Looking for a similar relationship in Valiant\u27s algebraic model of computation, we propose width of an arithmetic circuit as a possible measure of space. We introduce the class VL as an algebraic variant of deterministic log-space L. In the uniform setting, we show that our definition coincides with that of VPSPACE at polynomial width. Further, to define algebraic variants of non-deterministic space-bounded classes, we introduce the notion of ``read-once\u27\u27 certificates for arithmetic circuits. We show that polynomial-size algebraic branching programs can be expressed as a read-once exponential sum over polynomials in VL, ie $mbox{VBP}inSigma^R cdotmbox{VL}$. We also show that $Sigma^R cdot mbox{VBP} =mbox{VBP}$, ie VBPs are stable under read-once exponential sums. Further, we show that read-once exponential sums over a restricted class of constant-width arithmetic circuits are within VQP, and this is the largest known such subclass of poly-log-width circuits with this property. We also study the power of skew formulas and show that exponential sums of a skew formula cannot represent the determinant polynomial

Structural, Magnetic and Magneto-caloric studies of Ni50Mn30Sn20Shape Memory Alloy

We have synthesized a nominal composition of Ni50Mn30Sn20 alloy using arc melting technique. Rietveld refinement confirms the austenite L21 structure in Fm-3m space group. Electrical resistivity has been found to clearly exhibiting two different phenomena viz. a magnetic transition from paramagnetic to ferromagnetic and a structural transition from austenite to martensitic phase. Thermo-magnetization measurements M(T) confirms ferromagnetic transition temperature TC at 222 K and martensitic transition starting at 127 K(MS). Magnetization measurement M(H) at 10 K confirms the ferromagnetic state. Frequency dependence of ac susceptibility \c{hi}' at low temperature suggests spin glass behavior in the system. The isothermal magnetic entropy change values have been found to be 1.14 J/Kg.K, 2.69 J/Kg.K and 3.9 J/Kg.K, with refrigeration capacities of 19.6 J/kg, 37.8 J/kg and 54.6 J/kg for the field change of 1, 2 and 3 Tesla respectively at 227 K.Comment: 16 pages text + Figs. Ni50Mn30Sn20 alloy: reasonable refrigeration capacity tunable to Room