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Arsenic groundwater contamination exceeding 0.05 mg/l affecting the Newer Alluvial tracts of Patna and Bhojpur, the two worst affected districts located in the Middle Ganga Plain in the Bihar state, has been studied The area is underlain by two-tier Quaternary aquifer systems within a depth of 300 m below ground level, separated by a 15-32-m-thick clay/sandy clay aquitard. The upper part (

Long-duration gamma-ray bursts (GRBs) are widely believed to be highly-collimated explosions (opening angle theta ~ 1-10 deg). As a result of this beaming factor, the true energy release from a GRB is usually several orders of magnitude smaller than the observed isotropic value. Measuring this opening angle, typically inferred from an achromatic steepening in the afterglow light curve (a "jet" break), has proven exceedingly difficult in the Swift era. Here we undertake a study of five of the brightest (in terms of the isotropic prompt gamma-ray energy release, E(gamma, iso)) GRBs in the Swift era to search for jet breaks and hence constrain the collimation-corrected energy release. We present multi-wavelength (radio through X-ray) observations of GRBs 050820A, 060418, and 080319B, and construct afterglow models to extract the opening angle and beaming-corrected energy release for all three events. Together with results from previous analyses of GRBs 050904 and 070125, we find evidence for an achromatic jet break in all five events, strongly supporting the canonical picture of GRBs as collimated explosions. The most natural explanation for the lack of observed jet breaks from most Swift GRBs is therefore selection effects. However, the opening angles for the events in our sample are larger than would be expected if all GRBs had a canonical energy release of ~ 10e51 erg. The total energy release we measure for those "hyper-energetic" (E(total) >~ 10e52 erg) events in our sample is large enough to start challenging models with a magnetar as the compact central remnant., Submitted to ApJ, comments welcome

Movement and abstraction of groundwater in the geological formations are dependent on the hydro-geological parameters of the aquifers. The purpose of any aquifer test is to determine the hydro-geological parameters. Among the basic parameters are the specific storage, permeability and leakage coefficients. The hydro-geological parameters are hidden in the field test data and their identification is possible using the available physically plausible models suitable for the prevailing field circumstances. In this context, a generalized theoretical solution for the effect of partial penetration superimposed over the full penetration on draw-down in a large-diameter well in artesian aquifer discharging at a constant rate has been presented for non-dimensional quantities describing the variable geometries of wells. The well-function curves are developed by varying the percentage amount of drilling and the percentage amount of casing lowered which then control to vary the percentage amount of open-hole or screened interval for the three categories: when the diameter of the cased interval in which the water level changes is greater than, equal to, and less than the diameter of the open interval. The skin effect and the effect of leakage are neglected. A comparison of results with the published works has also been presented. The present study is useful in such areas where wells are located either in harder or in collapsible loose formations; and a decision is required that, at the planning, construction, or development stage, as to what extent the amount of drilling be reduced, and/or an additional amount of casing be lowered within the aquifer. Also this reduces the cost of well construction and development in a specific situation.

To investigate whether oral or intravenous hydration affects oligohydramnios in cases with normal biophysical profile scores.One hundred twenty-four gravidas with singleton pregnancies at or near term were identified during a 16-month period retrospectively as having oligohydramnios. A total of 50 subjects with normal biophysical profiles (8 of 10) whose labor was not induced at once fell into two nonrandom, convenience sample groups: (1) 20 who were advised to drink fluids, and (2) 30 given intravenous hydration. The remaining 74 cases with oligohydramnios consisted of 60 gravidas with normal biophysical profile scores and another 14 with low scores (or = 6 of 10), all of whom had labor induced promptly.Cases with normal fetal status showed comparably favorable amniotic fluid index changes. In all, 62.5% and 44.0% demonstrated improved indices after oral and intravenous hydration, respectively; mean change in amniotic fluid index was +0.7 and +0.6. The amount of intravenous hydration did not correlate with the frequency of amniotic fluid index change (46.6% increase with intravenous volumes ofor = 2,000 mL, 40.0% with volumesor = 2,500 mL), or with magnitude of change (average +1.3 and +0.6).Oral and intravenous hydration may correct uncomplicated oligohydramnios, but neither appears to be particularly advantageous over the other.

Because heterotopic pregnancy is rare, the presence of an intrauterine pregnancy tends to impede early diagnosis and definitive intervention for the ectopic component. Delay in diagnosing the condition and failure to proceed quickly with the requisite anesthesia and surgery can jeopardize both maternal well-being and survival of the intrauterine fetus.A patient with heterotopic pregnancy carried the intrauterine pregnancy to term following first-trimester rupture of the tubal pregnancy, with hypovolemic shock.Prompt diagnosis, rapid fluid and blood resuscitation, heart-sparing anesthesia and gentle, expeditious surgery collectively contributed to the favorable outcome for the mother and surviving infant.

Geoelectrical field studies on cavernous Precambrian limestones of the Cuddapah Basin were conducted on an experimental basis in parts of Kurnool district, Andhra Pradesh, India. The objective was to study the effectiveness of the technique in delineating potential ground-water zones in them. The studies were confined to two sites viz., a bore hole tapping a cavity in Koilkuntla limestones at Illurukothapeta near the township of Banganapalli and over dry and water-filled parts of the Bilum caves in Narji limestones near the village of Kolimiguntla. These represent small- and large-dimension cavities, respectively. The field studies at these sites comprised a number of radial Schlumberger resistivity soundings, Wenner and Lee resistivity profiling, Lee resistivity soundings, buried current source dipole-dipole resistivity mapping, mise-a-la masse potential measurements and self-potential measurements. It was possible to delineate the orientation and lateral extent of the cavity encountered at 13 m depth in the borehole and the western extension of the water filled part of Bilam cave occurring at 35 m depth. Results of radial soundings in demarcating the shallow cavity encountered in borehole and mise-a-la-masse potential measurements for demarcating the extension of the water filled Bilam cave were found significant and useful. Self-potential measurements revealed the direction of ground water flow near the borehole.