Fluid-melt partitioning of sulfur in differentiated arc magmas and the sulfur yield of explosive volcanic eruptions

The fluid-melt partitioning of sulfur (DSfluid/melt) in differentiated arc magmas has been experimentally investigated under oxidizing conditions (Re-ReO2 buffer) from 800 to 950°C at 200MPa. The starting glasses ranged in composition from trachyte to rhyolite and were synthesized targeting the composition of the residual melt formed after 10-60% crystallization of originally trachy-andesitic, dacitic and rhyodacitic magmas (Masotta and Keppler, 2015). Fluid compositions were determined both by mass balance and by Raman spectroscopy of fluid inclusions. DSfluid/melt increases exponentially with increasing melt differentiation, ranging from 2 to 15 in the trachytic melt, from 20 to 100 in the dacitic and rhyodacitic melts and from 100 to 120 in the rhyolitic melt. The variation of the DSfluid/melt is entirely controlled by the compositional variation of the silicate melt, with temperature having at most a minor effect within the range investigated. Experiments from this study were used together with data from the literature to calibrate the following model that allows predicting DSfluid/melt for oxidized arc magmas: lnDSfluid/melt=9.2-31.4·nbot-1.8·ASI-29.5·Al#+4.2·Ca#where nbot is the non-bridging oxygen atoms per tetrahedron, ASI is the alumina saturation index, Al# and Ca# are two empirical compositional parameters calculated in molar units (Al#=XAl2O3XSiO2+XTiO2+XAl2O3 and Ca#=XCaOXNa2O+XK2O).The interplay between fluid-melt partitioning and anhydrite solubility determines the sulfur distribution among anhydrite, melt and fluid. At increasing melt polymerization, the exponential increase of the partition coefficient and the decrease of anhydrite solubility favor the accumulation of sulfur either in the fluid phase or as anhydrite. On the other hand, the higher anhydrite solubility and lower partition coefficient for less polymerized melts favor the retention of sulfur in the melt. At equilibrium conditions, these effects yield a maximum of the sulfur fraction in the fluid phase for slightly depolymerized melts (nbot= 0.05-0.15). Our data allow quantitative predictions of the sulfur yield of explosive volcanic eruptions over a wide range of magma compositions

Role of magnetic resonance imaging in evaluation of perianal fistulas

Background: Perianal fistula is a common disorder that often recurs because of infection that was missed at surgery. Preoperative MR imaging can help to prevent recurrence. The purpose of the study was, in this article we study the various types of perianal fistulas with MR imaging and study the usefulness of MR imaging in delineating the primary tract and complications of perianal fistula.Methods: We studied MRI images of 35 patients with different types of perianal fistulas. MR imaging were performed on 1.5-T magnet MR system (Siemens magneto Essenza). Imaging was performed with multiplanar T1-weighted, T2-weighted and PDFS sequences.Results: Total 35 patients were studied, out of which 18 (51%) patients showed grade 1 (simple linear intersphincteric fistula), 5 (14%) showed grade 2 (intersphinc¬teric with abscess or secondary tract), 6 (21%) showed grade 3 (transsphincteric), 5 showed grade 5 (14%) (transsphincteric with abscess or secondary tract in ischiorectal or ischioanal fossa) and none (0%)showed  grade 5 (supralevator and translevator).Conclusions: MR imaging provides precise location of the fistulous track, and its relationship to pelvic floor and the sphincter complex   and helps in the identifi¬cation of secondary tracks and abscesses.   

Trends in Annual Seminar Papers of Ahmedabad Library Network: A Bibliometric Analysis

A Bibliometric Study of Communications Published in Journal of Informetrics from 2012 to 2016. This research study demonstrates a bibliometric study of scholarly communication published by Ahmedabad Library Network (ADINET) in proceedings of annual conference (seminar). ADINET celebrates Librarian’s Day every year to commemorate the birthday of Dr. S R Ranganathan by organizing seminar in Gujarat, a leading state of India. This bibliometric study is intended to bring out the results of seminar proceedings published by ADINET from 2005 to 2019. This study investigated 176 papers published in Proceedings of ADINET seminar during 15 years. Study revealed that most of authors prefers to write for this seminar as a single author and out of 176 research papers 119 papers are written as single author whereas 36 papers found with double author and 21 papers published with three authors. It is also found from the study that Rashmi Kumbar and Shailesh Yagnik both are prominent authors whereas Gujarat is leading state published a maximum number of papers

Simulation of heavy rainfall over Mumbai on 26 july 2005 using high resolution icosahedral gridpoint model GME

In this paper an attempt has been made to simulate the exceptionally heavy rainfall event over Mumbai (Bombay) on 26 July 2005. Santa Cruz observatory near the International Airport of Mumbai recorded 944.2 mm of rainfall between 0300 UTC of 26 July 2005 and 0300 UTC of 27 July 2005 breaking all previous records. Some nearby places also recorded very heavy rainfall. Consequently, a deluge flooded the city and life in Mumbai came to a standstill. Mesoscale models or regional models are normally used to simulate such a small scale phenomenon. The model used in this paper to simulate the rainfall is the operational global numerical weather prediction model (GME) developed by the Deutscher Wetterdienst, The German Weather Service. Using European Center for Medium range Weather Forecast-ECMWF at T511 L91 data as the initial condition for the GME model, 24 hours accumulated precipitation has been computed. The model has a horizontal resolution of 40 km with 40 vertical levels and time step of 133s. The computed rainfall agrees reasonably well with the actual precipitation. The localized heavy rainfall might have occurred over Mumbai possibly due to several factors such as: well-marked low pressure over Orissa and adjoining Jharkhand with associated cyclonic circulation extending up to mid-troposheric level; off-shore trough on the west coast of India; low level jet over the peninsular India; intense convection and orographic lifting and interactions among these meteorological phenomena of different scales

MR imaging of anterio cruciate ligament injuries

Background: Of all the ligaments of the knee joint the Anterior cruciate ligament (ACL) is the most commonly injured. It is an important pillar of the ligament stabilization of knee joint preventing anterior translation of Tibia over Fibula. Magnetic resonance imaging (MRI) is an excellent modality providing fine-resolution and multiplanar imaging without any radiation, for detection and evaluation of ACL injury with the associated injuries to other ligaments of the knee join. The purpose of the work was to study the role of MRI in classifying the ACL injuries.Methods: MRI Knee of 162 patients with ACL injuries was studied. All the MR imaging scans were performed on 1.5-T MR system (Siemens magnetom Essenza).Results: A total of 162 patients were studied in which majority of them i.e. 43 patients had interstitial sprain, 38 patients had complete tear, 33 patients had mucoid degeneration, 27 had partial tear and 14 had high grade partial tear, however 7 patients had normal ACL. There were associated injuries to the other ligaments of the knee joint along with ACL injury, medial meniscus tear being the most common and was seen in 39.50% followed by lateral meniscus tear in 9.87%, MCL tear in 6.79%, LCL tear in 1.85% and PCL tear in 2.46 %.Conclusions: MRI is a good modality for classifying ACL injury and evaluation of injuries to the associated ligaments

Dynamic modeling of three-phase upflow fixed-bed reactor including pore diffusion

The dynamics of a three-phase upflow fixed-bed reactor are investigated using a non-isothermal heterogeneous model including gas–liquid and liquid–solid mass transfer and diffusion/reaction phenomena inside the catalyst. The partial differential and algebraic equations involving three integration variables (time and two space coordinates) are solved via discretization of the spatial coordinates coupled with the Gear method. For a multistep hydrogenation on a shell catalyst, the model exhibits significant effects of the external and above all internal resistance to hydrogen transfer but also non-trivial internal hydrocarbons concentration profiles. A simplified model is compared with the extended one and with experimental data in transient regime. In the investigated conditions—hydrocarbons in large excess—the diffusion of hydrocarbons appears to be actually not limiting, so that the simplest model predicts accurately the transient reactor behavior

Bacteriological analysis of donor human milk in milk bank in an Indian setting

Background: Although human milk banking in India was started in 1984, limited data regarding bacteriological quality of milk are available. Objective: To find bacteriological contamination of milk samples in human milk bank. Methods: Retrospective analysis of milk samples from milk bank for the year 2009-2015 was done. Group A donor mothers were from postnatal or neonatal units of our hospital. Group B mothers were from milk donation camps organized at the community level. All milk samples were plated on blood agar for bacteriological analysis. Pre-pasteurized samples were analyzed for the year 2014-2015 only. Results: Total donor mothers were 3670. 1481 (40%) were from milk donation camp at the community level. 327 (9%) were preterm milk. 2.34% of post-pasteurized samples showed contamination as compared to 9.1% pre-pasteurized milk samples (p=0.002). Group A mothers showed a higher contamination rate as compared to Group B mothers in both pre-pasteurized (p<0.001) and post-pasteurized samples (p=0.006). The most common organisms isolated in pre-pasteurized samples were Gram-positive bacilli (51.89%), coagulase-negative staphylococci (CONS, 44.96%), and Gram-negative bacilli (3%). The most common organisms in post-pasteurized samples were Gram-positive bacilli (88.23%) and CONS (11.76%). No Gram-negative bacilli were isolated from post-pasteurized samples. Conclusion: Contamination rates in our study for both pre- and post-pasteurized samples are quite low as compared to other studies. Community collection of human milk was safe with regard to bacteriological contamination. Holder’s method of pasteurization is effective in reducing contamination