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Byline: C. Kesavachandran, M. Pathak, M. Fareed, V. Bihari, N. Mathur, A. Srivastava Background: Shop keepers dealing with pesticides are exposed to multiple pesticides that include organophosphates, organochlorines, carbamates, pyrethroids. [...]

Byline: S. Rastogi, Vipul. Singh, C. Kesavachandran, Jyoti, M.K.J. Siddiqui, N. Mathur, R. Bharti To evaluate the health impact of spraying organophosphorus insecticides (OPs), 34 male sprayers in the mango [...]

Byline: Manju. Rahi, D. Taneja, Amrita. Misra, N. Mathur, Suresh. Badhan BACKGROUND: Despite efforts by government and other agencies, neonatal morbidity and mortality continues to be high in India. Among [...]

The magnetic properties of a series of ferromagnetic/antiferromagnetic (FM/AFM) superlattices are examined. The multilayers are combined of five L[a.sub.2/3]S[r.sub.1/3]Mn[O.sub.3]/P[r.sub.2/3]C[a.sub.1/3]Mn[O.sub.3] (LSMO/PCMO) bilayers, grown by pulsed laser deposition using SrTi[O.sub.3] as the substrate.

Byline: C. Kesavachandran, S. Rastogi, N. Mathur, V. Bihari, A. Singh A study was conducted in beauty parlor workers of Lucknow, India, to assess the prevalence of respiratory morbidity and [...]

Objective: To determine the time to normalization of procalcitonin (PCT) levels and duration of antibiotics in neonatal sepsis.Methods: A prospective observational study design was used. The participants included were neonates with sepsis. The primary outcome measure was time to normalization of PCT levels and duration of antibiotics following clinical resolution.Results: Time to normalization of PCT levels was 9.6 ± 4.2 days in neonates with septic shock, 6.2 ± 2.5 days in neonates without shock, 9.6 ± 3.1 days in neonates with culture-positive sepsis and 6.4 ± 3.1 days in neonates with culture-negative sepsis. Time to normalization of PCT levels according to the stage of systemic inflammatory response syndrome was 5.8 ± 2.8 days in neonates with sepsis, 6.1 ± 3.1 days in those with sepsis syndrome, 6.3 ± 3.3 days in those with early septic shock and 9.4 ± 3.6 days in those with multiorgan dysfunction syndrome. There was no morbidity and mortality in any neonate in the 4-week follow-up.Conclusion: The duration of antibiotics can be determined by observing the time to normalization of PCT following clinical resolution of sepsis. [ABSTRACT FROM AUTHOR]

Uniaxial magnetic anisotropy was imposed on a CoFeB film by applying an in-plane magnetic field during growth. Electrically driven strain from a ferroelectric 0.68Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 (011) substrate resulted in giant magnetoelectric effects, whose coupling constant peaked at a record value of ∼8.0 × 10−6 s m−1. These large magnetoelectric effects arose due to non-volatile 90° rotations of the magnetic easy axis, reflecting a competition between the fixed growth anisotropy and the voltage-controlled magnetoelastic anisotropy. In contrast to previous work, our non-volatile rotations did not require the assistance of an applied magnetic field or the setting of an in-plane substrate polarization prior to deposition. [ABSTRACT FROM AUTHOR]

We report magnetic and electrical transport studies of an epitaxially grown trilayer thin film structure comprising La0.59Ca0.41MnO3 sandwiched between La0.7Ca0.3MnO3 electrodes. Since La0.59Ca0.41MnO3 lies at the edge of the thin film ferromagnetic metallic phase field, phase separation effects are expected. These effects can explain the observed magnetic isotropy of the middle layer. By contrast, the electrode material is magnetically uniaxial. Easy axis magnetic field sweeps of the trilayer produce two sharp magnetic transitions, but only one sharp transition in current-in-plane resistance measurements. [ABSTRACT FROM AUTHOR]

The magnetic properties of a series of ferromagnetic/antiferromagnetic (FM/AFM) superlattices are studied. The multilayers are composed of five La2/3Sr1/3MnO3/Pr2/3Ca1/3MnO3 (LSMO/PCMO) bilayers, grown by pulsed laser deposition using SrTiO3 as the substrate. The evolution of the magnetic moment with the AFM PCMO layer thickness (0<=tA<=7.6 nm) is analyzed and is found to be strongly affected by the strain fields introduced by the FM/AFM interfaces. The effect on the LSMO is the appearance of a magnetic dead layer of ∼1.5 nm, close to the interface with the PCMO. On the contrary, the magnetic moment of PCMO is remarkably enhanced for thicknesses tA around 3.5 nm, where nanometric FM droplets would find the optimal strain conditions to be accommodated within the AFM PCMO spacer. The implications of these findings on the magnetoresistance response are discussed. [ABSTRACT FROM AUTHOR]

We performed detailed studies of the magnetic domain structure and strain effects in epitaxial La[SUB1-x]Sr[SUBx]MnO[SUB3](001) films grown on SrTiO[SUB3](001) bicrystal substrates by combining magnetic force microscopy, x-ray diffraction, and classical magnetometry. We show that, in addition to magnetic domain walls which nucleate at grain boundaries, 180° magnetic domain walls not associated with structural defects form along the 〈100〉 direction. The size of the magnetic domains are of the order of tens of microns with the magnetic easy axes along the 〈100〉 direction in the plane of the film. Spin reorientation occurs at the grain boundaries, which we attribute to the different strain state compared to the grain interior. [ABSTRACT FROM AUTHOR]

Using x-ray submicrobeam, we spatially mapped the strain in epitaxial La[sub l-χ]Sr[sub χ]MnO[sub 3] films grown on SrTiO[sub 3](001) bicrystal substrates. Our results show that there is an elastic strain gradient at the artificial grain boundary, which decays over a length scale of ∼1 µm. The tensile strain at the interior of the grain—due to the lattice mismatch between La[sub l-χ]Sr[sub χ]MnO[sub 3] and SrTiO[sub 3]—relaxes as the film nears the grain boundary, yielding a grain boundary lattice constant which approaches the value of that in bulk La[sub l-χ]Sr[sub χ]MnO[sub 3]. [ABSTRACT FROM AUTHOR]

The magnetoresistance of grain boundaries in the perovskite manganites is being studied, both in polycrystalline materials, and thin films grown on bicrystal substrates, because of interest in low-field applications. In this article we show that epitaxial films grown on SrTiO[sub 3] bicrystal substrates of 45° misorientation show magnetoresistance behavior which is strongly dependent on the thickness of the film. Thin films, e.g., 40 nm, can show a large low-field magnetoresistance at low temperatures, with very sharp switching between distinct high and low resistance states for fields applied in plane and parallel to the boundary. Thicker films show a more complex behavior of resistance as a function of field, and the dependence on the angle between the applied field and the grain boundary is altered. These changes in magnetoresistance behavior are linked to the variation in morphology of the films. Thin films are coherently strained, due to the mismatch with the s! ubstrate, and very smooth. Thicker films relax, with the formation of defects, and hence different micromagnetic behavior. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Magnetic domain structure of La[sub 1-x]Sr[sub x]MnO[sub 3] films was studied using magnetic force microscopy (MFM). Evolution of the magnetic patterns was monitored as a function of temperature by using a variable temperature sample stage. The magnetic contrast in the MFM images decreases as the temperature is raised and vanishes as the system approaches the T[sub c] of the film. At temperatures above the T[sub c] of the film, local ferromagnetic regions with a higher T[sub c] are detected around the grain boundaries. We attribute this variation in the local T[sub c] to the local variation of strain in the film. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]