Study of effective interaction from single particle transfer reactions on f-p shell nuclei

The present study concentrates on the average effective two-body interaction matrix elements being extracted, using sum-rule techniques, from transfer reactions on target states having single orbital as well as two orbitaloccupancy. This investigation deals with transfer reactions on f-p shell nuclei involving (i) $1f_{7/2}$ and $2p_{3/2}$ transfer on target states using $^{40}$Ca as inert core, and (ii) $2p_{3/2}$ and$1f_{5/2}$ transfer on states using $^{56}$Ni as core.Comment: 12 pages, ptptex Subj-Classes: Nuclear Shell Structure e-mail:[email protected]

Effective two-body interactions in the s-d shell nuclei from sum rules equations in tranfer reactions

Average effective two-body interaction matrix elements in the s-d shell have been extracted, from data on experimentally measured isospin centroids, by combining the recently derived new sum rules equations for pick-up reactions with similar known equations for stripping reactions performed on general multishell target states. Using this combination of stripping and pick-up equations, the average effective matrix elements for the shells, 1d^2_5/2, 2s^2_1/2 and 1d^2_3/2 respectively have been obtained. A new feature of the present work is that the restriction imposed in earlier works on target states, that it be populated only by active neutrons has now been abandoned.Comment: 12 pages, RevTeX, e-mail: [email protected]

Genus Ramaria in the Eastern Himalaya: subgenus Laeticolora-I

In this paper an account of 11 taxa of the genus Ramaria (Fr.) Bonorden collected from different localities in the eastern Himalaya and adjoining hills is given. Of the taxa included, Ramaria conjunctipes, Ramaria araiospora var. rubella, Ramaria xanthosperma, Ramaria rubribrunnescens, Ramaria flavigelatinosa, Ramaria flavigelatinosa var.carnisalmonea and Ramaria gelatiniaurantia are new records for the Himalayas; while Ramaria rubrogelatinosa, Ramaria brevispora, Ramaria brevispora var. albida and Ramaria perbrunnea were not known earlier from the eastern Himalaya

The role of the H2_2 adiabatic index in the formation of the first stars

The adiabatic index of H$_2\,$ ($\gamma_{\mathrm{H_2}}$) is non-constant at temperatures between $100-10^4\,\mathrm{K}$ due to the large energy spacing between its rotational and vibrational modes. For the formation of the first stars at redshifts 20 and above, this variation can be significant because primordial molecular clouds are in this temperature range due to the absence of efficient cooling by dust and metals. We study the possible importance of variations in $\gamma_{\mathrm{H_2}}$ for the primordial initial mass function by carrying out 80 3D gravito-hydrodynamic simulations of collapsing clouds with different random turbulent velocity fields, half using fixed $\gamma_{\rm H_2} = 7/5$ in the limit of classical diatomic gas (used in earlier works) and half using an accurate quantum mechanical treatment of $\gamma_{\mathrm{H_2}}$. We use the adaptive mesh refinement code FLASH with the primordial chemistry network from KROME for this study. The simulation suite produces almost 400 stars, with masses from $0.02 - 50$ M$_\odot$ (mean mass $\sim 10.5\,\mathrm{M_{\odot}}$ and mean multiplicity fraction $\sim 0.4$). While the results of individual simulations do differ when we change our treatment of $\gamma_{\mathrm{H_2}}$, we find no statistically significant differences in the overall mass or multiplicity distributions of the stars formed in the two sets of runs. We conclude that, at least prior to the onset of radiation feedback, approximating H$_2$ as a classical diatomic gas with $\gamma_{\rm H_2} = 7/5$ does not induce significant errors in simulations of the fragmentation of primordial gas. Nonetheless, we recommend using the accurate formulation of the H$_2\,$ adiabatic index in primordial star formation studies since it is not computationally more expensive and provides a better treatment of the thermodynamics.Comment: 14 pages, 10 figures, accepted for publication in MNRA

The importance of magnetic fields for the initial mass function of the first stars

Magnetic fields play an important role for the formation of stars in both local and high-redshift galaxies. Recent studies of dynamo amplification in the first dark matter haloes suggest that significant magnetic fields were likely present during the formation of the first stars in the Universe at redshifts of 15 and above. In this work, we study how these magnetic fields potentially impact the initial mass function (IMF) of the first stars. We perform 200 high-resolution, three-dimensional (3D), magneto-hydrodynamic (MHD) simulations of the collapse of primordial clouds with different initial turbulent magnetic field strengths as predicted from turbulent dynamo theory in the early Universe, forming more than 1100 first stars in total. We detect a strong statistical signature of suppressed fragmentation in the presence of strong magnetic fields, leading to a dramatic reduction in the number of first stars with masses low enough that they might be expected to survive to the present day. Additionally, strong fields shift the transition point where stars go from being mostly single to mostly multiple to higher masses. However, irrespective of the field strength, individual simulations are highly chaotic, show different levels of fragmentation and clustering, and the outcome depends on the exact realisation of the turbulence in the primordial clouds. While these are still idealised simulations that do not start from cosmological initial conditions, our work shows that magnetic fields play a key role for the primordial IMF, potentially even more so than for the present-day IMF.Comment: 17 pages, 9 figures, 3 tables; accepted for MNRAS, minor revisions from submitted versio

Performance of variable-orifice nozzles for liquid fertilizer applications

Citation: Sharda, A., Fulton, J. P., & Taylor, R. K. (2016). Performance of variable-orifice nozzles for liquid fertilizer applications. Applied Engineering in Agriculture, 32(3), 347-352. doi:10.13031/aea.32.11428Variable-rate application continues to gain interest among precision agriculture practitioners including the use of crop sensor technology for application of nitrogen in grain crops. For liquid fertilizers, variable-orifice nozzles are being implemented since they provide a much larger nozzle flow range compared to traditional fixed orifice nozzles. However, understanding the performance of variable-orifice nozzles under different field operating conditions has been limited. Therefore, the objective of this study was to evaluate the performance of variable orifice nozzles in support of variable-rate application. Two common variable-orifice nozzles offered by different companies were selected for this study. They were tested over three flow ranges (0.76 to 1.89 L/min) with all tests replicated three times. A commercially available 18.6-m, wet boom sprayer equipped with 37 nozzle bodies was used. Nozzles were numbered but then randomly assigned a position along the boom. To evaluate the performance of an individual nozzle, three random nozzle locations along the spray boom were established for both sets of nozzles. Therefore, 18 tests per replication were required to include the 3 flow rates, 3 different locations, and 2 nozzle types. Once the desired flow rate test was established, tip flow was measured using SpotOn Sprayer Calibrator technology. Tip flows were recorded and statistical analyses performed to evaluate flow uniformity (CV) across the boom but also detect off-rate errors by individual nozzles and locations across the boom. With the exception of a few nozzles, the uniformity across the spray boom, as defined by the CV, was acceptable for both nozzle types over approximately a 2:1 flow range. Both nozzle types were less uniform at the low flow rate. There were three nozzles of each type that resulted in unacceptable flow errors in multiple tests. © 2016 American Society of Agricultural and Biological Engineers

Protective Effects of the Novel Phytonutrient S7 Against Intestinal Tight Junction Disruption: Composition Matters

The prevalence of intestinal inflammatory diseases is increasing, and pharmacologic agents for intervention are currently limited. Preserving epithelial tight junction (TJ) integrity and preventing underlying immune cell activation by intestinal bacteria are key targets for abrogating the perpetual inflammatory cycle that plagues these diseases. Phytonutrients have shown promise for their ability to reduce cellular inflammation, but the extent of their efficacy in an intestinal model of inflammation is not well understood. Here, we hypothesized that S7, a novel phytonutrient derived from extracts rich in curcuminoids and catechins, would reduce immune cell inflammation and preserve TJ integrity in an in vitro co-culture model of intestinal inflammation. We further investigated whether a curcumin-containing formulation (S7-C) or its metabolite, tetrahydrocurcumin (S7-THC) would similarly preserve TJ integrity. An in vitro intestinal co-culture model was established by seeding Caco-2 epithelial cells on semipermeable transwell inserts 21 days prior to the addition of RAW264.7 macrophages in the basolateral chamber. Macrophages were next stimulated with 10 ng/ml lipopolysaccharide (LPS) to induce inflammation, and subsequent TJ disruption in the co-cultured Caco-2 cells was assessed by transepithelial electrical resistance (TEER) using epithelial ohmmeter chopstick electrodes. We found that administration of S7-THC containing 1-5 μM THC produced dose dependent mitigation of LPS-induced decreases in TEER and approached the efficacy of the pharmacologic agent, budesonide. However, S7-C at 5 μM curcumin was unable to preserve TEER, suggesting that the specific combination of phytonutrients is important for preventing inflammation-induced TJ disruption. We also found that, though apical application (Caco-2 only) of budesonide was sufficient for preserving TEER in our model, S7-THC required both apical (Caco-2) and basolateral (RAW264.7) treatment, suggesting that reducing macrophage inflammation is important for limiting epithelial TJ disruption in this context. Interestingly, S7-C was more effective than S7-THC or budesonide at reducing inflammatory basolateral nitric oxide (NO) production as determined by the Griess assay. This suggests that, though S7-C more effectively reduces this aspect of inflammation, another inflammatory mediator is responsible for conveying TJ disruption and is governed differentially by S7-THC. Further support of this comes from our finding that S7-THC, but not S7-C, ameliorated the LPS-induced increase in myosin light chain kinase (MLCK) expression in Caco-2 cells as determined by Western blot. Together, these findings suggest that phytonutrients such as S7-THC have prophylactic potential in the preservation of TJ integrity, and the specific composition of these phytonutrients matters

Comparison of I-gel and laryngeal mask airway classic in terms of ease of insertion and hemodynamic response: a randomised observational study

Background: The gold standard technique for preserving a patent airway throughout anaesthesia is tracheal intubation. I-gel is a relatively new addition to the SADs. I-gel has combined the concept of the non-cuffed SADs like the SLIPA and gastric tube of the proseal LMA yet retaining the shape of laryngeal mask. Hence, we have compared ease of insertion, number and duration of insertion attempts among the two devices. Methods: This study was conducted on patients undergoing elective surgery under GA in Pacific Medical College and Hospital, Udaipur. Patients were divided into two groups: group A= LMA classic, a variant of supraglottic airway device and group B= I-gel, a variant of supraglottic airway device. The two devices were than compared with respect to success rate of insertion, time taken for insertion and ease of gastric tube placement (number of attempts) and post-operative airway morbidity. Results: Mean insertion time was 8.66±3.21 seconds in C-LMA and 6.49±1.92 seconds in I-gel (p<0.001). 97.14% was the success rate of single time attempt insertion with I-gel as compared to 88.57% in C-LMA. There was a failure rate of 11.43% in single attempt insertion with CLMA as compared to 2.86% with I-gel (p>0.05). Conclusions: We hereby concluded with our study that successful and shorter duration of insertion, with less hemodynamic response, makes I-gel™ a suitable alternative to LMA classic™ during general anesthesia