Tunneling Study of the Charge-Ordering Gap on the Surface of La0.350_{0.350}Pr0.275_{0.275}Ca0.375_{0.375}MnO3_3 Thin Films

Variable temperature scanning tunneling microscopy/spectroscopy studies on (110) oriented epitaxial thin films of La$_{0.350}$Pr$_{0.275}$Ca$_{0.375}$MnO$_3$ are reported in the temperature range of 77 to 340 K. The films, grown on lattice matched NdGaO$_3$ substrates, show a hysteretic metal-insulator transition in resistivity at 170 K. The topographic STM images show step-terrace morphology while the conductance images display a nearly homogeneous surface. The normalized conductance spectra at low temperatures (T$<$150 K) show an energy gap of 0.5 eV while for T$\geq$180 K a gap of 0.16 eV is found from the activated behavior of the zero bias conductance. The presence of energy gap and the absence of phase separation on the surface over more than 2 $\mu$m$\times$2 $\mu$m area contradicts the metallic behavior seen in resistivity measurements at low temperatures. We discuss the measured energy gap in terms of the stabilization of the insulating CO phase at the film surface.Comment: 5 pages, 5 figures To appear in Phys. Rev.

High Performance Fortran and Possible Extensions to support Conjugate Gradient Algorithms

We evaluate the High-Performance Fortran (HPF) language for the compact expression and efficient implementation of conjugate gradient iterative matrix-solvers on High Performance Computing and Communications(HPCC) platforms. We discuss the use of intrinsic functions, data distribution directives and explicitly parallel constructs to optimize performance by minimizing communications requirements in a portable manner. We focus on implementations using the existing HPF definitions but also discuss issues arising that may influence a revised definition for HPF-2. Some of the codes discussed are available on the World Wide Web at http://www.npac.syr.edu/hpfa/ alongwith other educational and discussion material related to applications in HPF

Eco-friendly fishing methods and techniques practiced in the northern hills zone of Chhattisgarh state, India

Indian forests have the potential to safeguard the livelihood of forest dwelling people, particularly tribal people, who are among the most disadvantaged groups in our society. Tribal people generally depend on forests for their cultural, spiritual, and to varying degree of economic needs. Fishing is one of the important livelihood activities of the tribal community since the time immortal. Fishing provides the source of livelihood as well as nutritional security to the tribal family significantly. An explorative study was conducted in participatory mode to explore the eco-friendly fishing methods. Totally, 300 respondents were selected for this study. The data was documented with the help of participatory observation, focused group discussions with triangulation procedures. In the paper, eco-friendly fishing methods such as Kumani, Pahata, Mora, Donga, Pelna, Choppa, Mora, Gulel, Bhawarjal, Ditori, Beetaah, Chiwaar, Baahla and Jholna and their working procedures are discussed. Jholna used to catch small and medium sized fishes upto 5-7 kg/day. The production cost of this choppa is less than Rs. 250 and it is used to catch small sized fishes up to 1.5-2.5kg/day. Kumani is used to catch small sized fishes and crabs upto 1-2 kg/day. The making cost of Pelna is around Rs. 650 and it is used to catch fishes upto 6-7 kg/day. The construction cost of Pahata gear is around Rs. 2000 and It is used to catch medium to big sized fishes upto 8-10kg/day

An exploratory study on cultural and health significance of traditional tattooing practices among tribal community in Chhattisgarh state, India

This explorative study carried out from four districts of Chhattisgarh state namely Surajpur, Surguja, Balrampur and Jashpur. From each district, four villages were selected and from each village 25 tribal respondents were selected thus 300 respondents were selected for this study. About 65.33 percent of the tribal were between 36and 50 years of age group, more than one fourth (34.67%) of the farmers were educated up to primary school level, about half (49.00 %) of the respondents were at the income range of Rs. 25,001 to Rs. 75,000 and about 80% of the population of the state is rural and the main livelihood of the villagers is agriculture and agriculture-based small industry. Tattooing is one of the livelihood option for the tribal community in the study area. Tattooing has been practiced across the world since at least Neolithic times (7000 BCE), as confirmed by mummified preserved skin, prehistoric art, literatures, poetry, proverbs and the archaeological records. In Southern India, permanent tattoos are called pachakutharathu. In northern India, permanent tattoos are called Godna. Tattoos have been used as cultural symbols among many tribal populations, as well as the caste-based Hindu population of India. These tattoos have also been used as integral part of the tribal’s lifestyle Chhattisgarh state of India

Multi-wavelength Diagnostics of the Precursor and Main phases of an M1.8 Flare on 2011 April 22

We study the temporal, spatial and spectral evolution of the M1.8 flare, which occurred in NOAA AR 11195 (S17E31) on 22 April 2011, and explore the underlying physical processes during the precursors and their relation to the main phase. The study of the source morphology using the composite images in 131 {\deg}A wavelength observed by the SDO/AIA and 6-14 keV revealed a multiloop system that destabilized systematically during the precursor and main phases. In contrast, HXR emission (20-50 keV) was absent during the precursor phase, appearing only from the onset of the impulsive phase in the form of foot-points of emitting loop/s. This study has also revealed the heated loop-top prior to the loop emission, although no accompanying foot-point sources were observed during the precursor phase. We estimate the flare plasma parameters viz. T, EM, power-law index, and photon turn-over energy by forward fitting RHESSI spectral observations. The energy released in the precursor phase was thermal and constituted ~1 per cent of the total energy released during the flare. The study of morphological evolution of the filament in conjunction with synthesized T and EM maps has been carried out which reveals (a) Partial filament eruption prior to the onset of the precursor emission, (b) Heated dense plasma over the polarity inversion line and in the vicinity of the slowly rising filament during the precursor phase. Based on the implications from multi-wavelength observations, we propose a scheme to unify the energy release during the precursor and main phase emissions in which, the precursor phase emission has been originated via conduction front formed due to the partial filament eruption. Next, the heated leftover S-shaped filament has undergone slow rise and heating due to magnetic reconnection and finally erupted to produce emission during the impulsive and gradual phases.Comment: 16 Pages, 11 Figures, Accepted for Publication in MNRAS Main Journa

A study on the response of Indian dip and low latitude ionospheric regions to a limb centred X9.0 class solar flare

In this paper, we present how Indian dip equatorial and low latitude ionospheric system responded to a limb centred X9.0 class of solar flare event using GPS-TEC, Ionosonde and magnetometer measurements. The limb centred X9.0 solar flare was materialise on 05 December 2006 at the heliography coordinate S07E68 and NOAA 10930 active region, started at 10:18 UT (15:48 IST), peaked at 10:35 UT (16:05 IST), and decayed by 10:45 UT (16:15 IST). The measurements of the total electron content (TEC) of 30 s time resolutions from a series of GPS receivers installed near the dip and low latitude regions does not show TEC enhancement during peak flare hours, 10:35 UT (16:05 IST). An appreciable enhancement in the TEC units (∼5 TEC units) is noticeable during post flare hours, 13:00 UT (18:30 IST) which is high at dip equatorial compare to low latitude regions. The Ionosonde measurement of 15 min time resolution at dip equatorial station shows an increase in the plasma density at the F-region while the E-region did not show any impact during peak flare hours, 10:35 UT (16:05 IST). The analysis of horizontal component of geomagnetic field (H) of 1 min time resolution data obtained from the INTERMAGNET shows sudden rise in electron density in the E-region of the ionosphere and intensification in the ionospheric current system in eastward direction at the dip equatorial and reverse in direction at low latitude regions at 10:35 UT (16:05 IST). Present analyses contribute our understanding about plasma dynamics during flare and post flare hours in the E and F-regions of Indian dip and low latitude Ionosphere

Signature capture of red soil patches and their acidity-A case study of Banka district, Bihar, India

Colour in soils as well as other object is the visual perceptual property which is perceived by human eye. They are governed by spectrum of light corresponding to wavelength or reflected energy of the material. Developed model for soil acidity is based on visual interpretation, principal component and spectral enhancement techniques by using of the satellite image (IRS LISS III, 2014). In this context, red soil patch is much sensitive in red spectral band comparison to green and blue spectral bands and perceived as red tone by human eyes but same soil patch appears green in false colour composite (FCC) image of NIR (0.70-0.80?m), Red (0.60-0.70 ?m) and Green (0.50-0.60?m) bands. The maximum coverage of red soil patches having low pH &lt; 6.5 (1:2.5) was recognized in 44.07 per cent of the total geographical area (3019.56 sq.km) under Banka district. Maximum red soil patches having their acidity were recognised in Katoria (18.56%), Chanan (15.15%), Bounsi (10.44%) and Banka (9.92%) blocks. Overall results indicated that variation of tone in different bands helps for the separation of red soil patches

Generic effective source for scalar self-force calculations

A leading approach to the modelling of extreme mass ratio inspirals involves the treatment of the smaller mass as a point particle and the computation of a regularized self-force acting on that particle. In turn, this computation requires knowledge of the regularized retarded field generated by the particle. A direct calculation of this regularized field may be achieved by replacing the point particle with an effective source and solving directly a wave equation for the regularized field. This has the advantage that all quantities are finite and require no further regularization. In this work, we present a method for computing an effective source which is finite and continuous everywhere, and which is valid for a scalar point particle in arbitrary geodesic motion in an arbitrary background spacetime. We explain in detail various technical and practical considerations that underlie its use in several numerical self-force calculations. We consider as examples the cases of a particle in a circular orbit about Schwarzschild and Kerr black holes, and also the case of a particle following a generic time-like geodesic about a highly spinning Kerr black hole. We provide numerical C code for computing an effective source for various orbital configurations about Schwarzschild and Kerr black holes.Comment: 24 pages, 7 figures, final published versio