Comparison of forced expiratory spirometric flow changes following intrathecal bupivacaine and bupivacaine with fentanyl

Background: Higher dermatomal block following spinal anaesthesia impairs inspiratory capacity and decreases forced expiratory flow rates. This decrease in forced expiratory flows can in turn decrease the effectiveness of cough. Intrathecal opioids are important adjuncts to intrathecal local anaesthetics. The objective of our study was to compare the decrease in forced expiratory flows from the baseline values after subarachnoid block with bupivacaine and bupivacaine with fentanyl.Methods: Institutional ethics committee approval was obtained. Forty ASA I and II adult males, scheduled for elective surgery were included in the study. Informed written consent was obtained from all patients who were randomly allocated into two groups. Group B received intrathecal anaesthesia 15 mgs of bupivacaine with 0.5 ml of normal saline and Group BF received 15 mgs of bupivacaine with 0.5 ml of fentanyl (25 μg) intrathecally. The patients were instructed about the performance of the spirometry on the previous evening of the surgery. Forced vital capacity, forced expiratory volume in one second, peak expiratory flow rate and maximum expiratory pressure (Forced expiratory flows) were measured in supine position before intrathecal block and at 10, 60 and 120 minutes, following the establishment of the block. Highest dermatomal level of sensory blockade was noted.Results: There was no statistically significant difference in the baseline values of FVC (Group B: 4.188 ± 0.821, Group BF: 4.186 ± 0.575, p – 0.127), FEV1 (Group B: 3.301 ± 0.846, Group BF: 3.276 ± 0.825, p – 0.240), PEFR (Group B: 458.6 ± 43.024, Group BF: 452.6 ± 41.036, p -0.091 ) and PEmax (Group B: 52.64 ± 4.029, Group BF: 53 ± 3.162, p – 0.119 ) between the two groups. There was highly significant reduction in the values of FVC, PEFR and PEmax when compared to the baseline in both the groups at all three study periods. There was an acute reduction in the values of FVC, FEV1, PEFR and PEmax at 10 minutes. The graphs then achieve a plateau from 10 minutes to 60 minutes. From 60 to 120 minutes there was a gradual upslope in the graph. With regards to FEV1, though at 10 and 60 minutes there were statistically significant reductions when compared to the baseline values in both the groups, at 120 minutes the reductions were not significant. At all three time periods there was no difference in the reductions in FVC, FEV1, PEFR and PEmax values among the two groups. None of the patients in both the groups had PEFR and PEmax values below the critical value. Conclusion: The addition of 25 μg of fentanyl to intrathecal bupivacaine did not have any adverse effect on forced expiratory flows. There was a decrease in forced expiratory flows in both groups, but the decrease in PEFR and PEmax were never below the critical values. It is unlikely that a combination of intrathecal local anaesthetic and opioids will impair the normal patient’s ability to cough effectively

Design and development of a vertical plate precision seed metering device with positive seed knockout mechanism

Planting of seeds according to agronomical requirements is one of the most important and critical farm operations for crop cultivation. Placing of seeds at proper location is required to maintain plant to plant spacing in a row. A vertical plate precision seed metering device was designed and developed for field pea. Cells with three different depths of 8.48, 8.85 and 9.22 mm and three shapes of 20o, 30o and 40o left side angles were designed to obtain nine different plates. A seed metering device with different plates was fabricated and mounted on experimental setup. Performance of the metering device was evaluated under laboratory condition at three speeds of 37.04, 44.45 and 51.86 rpm. The results showed occurrence of stuck up seeds in the cells and higher missing hills which may be due to non-release of seeds from the seed metering device. In order to seed release from the metring device, a mechanism for positive seed knockout was designed and was incorporated in the developed metering device of different sizes and shapes of vertical plates. The performance of vertical plate precision seed metering device with positive seed knockout mechanism was also evaluated under laboratory conditions. The results showed that cell of 8.48 mm depth and 40o left side angle on a vertical plate seed metering device with positive seed knockout mechanism performed better with lowest average missing index of 2.67%, 0.5% multiple index and highest uniformity of seed placement of 96.83%. Stuck up of seeds in the cells of the seed metering device was not observed after incorporating positive seed knockout mechanism

Augmenting Pentose Utilization and Ethanol Production of Native Saccharomyces cerevisiae LN Using Medium Engineering and Response Surface Methodology

Economics of ethanol production from lignocellulosic biomass depends on complete utilization of constituent carbohydrates and efficient fermentation of mixed sugars present in biomass hydrolysates. Saccharomyces cerevisiae, the commercial strain for ethanol production uses only glucose while pentoses remain unused. Recombinant strains capable of utilizing pentoses have been engineered but with limited success. Recently, presence of endogenous pentose assimilation pathway in S. cerevisiae was reported. On the contrary, evolutionary engineering of native xylose assimilating strains is promising approach. In this study, a native strain S. cerevisiae LN, isolated from fruit juice, was found to be capable of xylose assimilation and mixed sugar fermentation. Upon supplementation with yeast extract and peptone, glucose (10%) fermentation efficiency was 78% with ~90% sugar consumption. Medium engineering augmented mixed sugars (5% glucose + 5% xylose) fermentation efficiency to ~50 and 1.6% ethanol yield was obtained with concomitant sugar consumption ~60%. Statistical optimization of input variables Glucose (5.36%), Xylose (3.30%), YE (0.36%), and peptone (0.25%) with Response surface methodology led to improved sugar consumption (74.33%) and 2.36% ethanol within 84 h. Specific activities of Xylose Reductase and Xylitol Dehydrogenase exhibited by S. cerevisiae LN were relatively low. Their ratio indicated metabolism diverted toward ethanol than xylitol and other byproducts. Strain was tolerant to concentrations of HMF, furfural and acetic acid commonly encountered in biomass hydrolysates. Thus, genetic setup for xylose assimilation in S. cerevisiae LN is not merely artifact of xylose metabolizing pathway and can be augmented by adaptive evolution. This strain showed potential for commercial exploitation

Dilepton mass spectra in p+p collisions at sqrt(s)= 200 GeV and the contribution from open charm

The PHENIX experiement has measured the electron-positron pair mass spectrum from 0 to 8 GeV/c^2 in p+p collisions at sqrt(s)=200 GeV. The contributions from light meson decays to e^+e^- pairs have been determined based on measurements of hadron production cross sections by PHENIX. They account for nearly all e^+e^- pairs in the mass region below 1 GeV/c^2. The e^+e^- pair yield remaining after subtracting these contributions is dominated by semileptonic decays of charmed hadrons correlated through flavor conservation. Using the spectral shape predicted by PYTHIA, we estimate the charm production cross section to be 544 +/- 39(stat) +/- 142(syst) +/- 200(model) \mu b, which is consistent with QCD calculations and measurements of single leptons by PHENIX.Comment: 375 authors from 57 institutions, 18 pages, 4 figures, 2 tables. Submitted to Physics Letters B. v2 fixes technical errors in matching authors to institutions. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Inclusive cross section and double helicity asymmetry for \pi^0 production in p+p collisions at sqrt(s)=200 GeV: Implications for the polarized gluon distribution in the proton

The PHENIX experiment presents results from the RHIC 2005 run with polarized proton collisions at sqrt(s)=200 GeV, for inclusive \pi^0 production at mid-rapidity. Unpolarized cross section results are given for transverse momenta p_T=0.5 to 20 GeV/c, extending the range of published data to both lower and higher p_T. The cross section is described well for p_T < 1 GeV/c by an exponential in p_T, and, for p_T > 2 GeV/c, by perturbative QCD. Double helicity asymmetries A_LL are presented based on a factor of five improvement in uncertainties as compared to previously published results, due to both an improved beam polarization of 50%, and to higher integrated luminosity. These measurements are sensitive to the gluon polarization in the proton, and exclude maximal values for the gluon polarization.Comment: 375 authors, 7 pages, 3 figures. Submitted to Phys. Rev. D, Rapid Communications. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

System Size and Energy Dependence of Jet-Induced Hadron Pair Correlation Shapes in Cu+Cu and Au+Au Collisions at sqrt(s_NN) = 200 and 62.4 GeV

We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from {dijets} in Cu+Cu and Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from \Delta\phi=\pi in central and semi-central collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models.Comment: 464 authors from 60 institutions, 6 pages, 3 figures, 2 tables. Submitted to Physical Review Letters. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Measurement of Bottom versus Charm as a Function of Transverse Momentum with Electron-Hadron Correlations in p+p Collisions at sqrt(s)=200 GeV

The momentum distribution of electrons from semi-leptonic decays of charm and bottom for mid-rapidity |y|<0.35 in p+p collisions at sqrt(s)=200 GeV is measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) over the transverse momentum range 2 < p_T < 7 GeV/c. The ratio of the yield of electrons from bottom to that from charm is presented. The ratio is determined using partial D/D^bar --> e^{+/-} K^{-/+} X (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in p_T. A fixed-order-plus-next-to-leading-log (FONLL) perturbative quantum chromodynamics (pQCD) calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is \sigma_{b\b^bar}= 3.2 ^{+1.2}_{-1.1}(stat) ^{+1.4}_{-1.3}(syst) micro b.Comment: 432 authors, 6 pages text, 3 figures. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Improved Measurement of Double Helicity Asymmetry in Inclusive Midrapidity pi^0 Production for Polarized p+p Collisions at sqrt(s)=200 GeV

We present an improved measurement of the double helicity asymmetry for pi^0 production in polarized proton-proton scattering at sqrt(s) = 200 GeV employing the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The improvements to our previous measurement come from two main factors: Inclusion of a new data set from the 2004 RHIC run with higher beam polarizations than the earlier run and a recalibration of the beam polarization measurements, which resulted in reduced uncertainties and increased beam polarizations. The results are compared to a Next to Leading Order (NLO) perturbative Quantum Chromodynamics (pQCD) calculation with a range of polarized gluon distributions.Comment: 389 authors, 4 pages, 2 tables, 1 figure. Submitted to Phys. Rev. D, Rapid Communications. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration

Extensive experimental data from high-energy nucleus-nucleus collisions were recorded using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The comprehensive set of measurements from the first three years of RHIC operation includes charged particle multiplicities, transverse energy, yield ratios and spectra of identified hadrons in a wide range of transverse momenta (p_T), elliptic flow, two-particle correlations, non-statistical fluctuations, and suppression of particle production at high p_T. The results are examined with an emphasis on implications for the formation of a new state of dense matter. We find that the state of matter created at RHIC cannot be described in terms of ordinary color neutral hadrons.Comment: 510 authors, 127 pages text, 56 figures, 1 tables, LaTeX. Submitted to Nuclear Physics A as a regular article; v3 has minor changes in response to referee comments. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm