679 research outputs found
Mass Determination Method for the Right and Left Selectron Above Production Threshold
The determination of the masses of Supersymmetric particles such as the
Selectron for energies above threshold using the energy end-points method is
subject to signal deconvolution difficulties and to Standard Model and
Supersymmetric backgrounds. The important features of Right and Left Selectron
production are used to design an experimentally robust method both for
determining the Left and Right Selectron masses, the Neutralino mass and for
suppresing backgrounds. The mass resolution is an order of magnitude better
than in previous methods. Additional features, such as the determination of the
relative leptonic branching ratios of the selectron decay are present in the
method.Comment: 4 pages in RevTex (Latex) format and 4 figures in eps forma
Lead isotopes behavior in the fumarolic environment of the Piton de la Fournaise volcano (Reunion Island)
International audienceThe recent activity of the Piton de la Fournaise volcano offers a rare opportunity to address the issue of Pb isotope behavior in volcanic fumaroles, as the composition of the degassing source is accurately and precisely known. Gas sublimates formed between 2007 and 2011 at temperature ranging from 400 to ca. 100 degrees C include Na-K sulfate (aphthitalite), Ca-Cu sulfate (e.g., gypsum), Na sulfate (thenardite), Ca-Mg-Al-Fe fluoride (e.g., ralstonite) and native sulfur. The high-temperature deposits show trace element patterns typical of volcanic gas (with Pb concentration up to 836 ppm) while the low-temperature deposits are depleted in most volatile elements (Pb <1 ppm) with the exception of Pd and Tl (in fluorides) and Se (in native sulfur). Only for low-temperature fluoride samples do Pb isotope compositions plot significantly outside the field of lavas. The isotopic shift is ascribed to leaching ubiquitous unradiogenic phases (e.g., sulfides) by acidic gas condensates. The similarity in Pb isotope signature between lavas and sublimate samples more representative of the gas phase (sulfates) indicates that the net fractionation of Pb isotopes resulting from volatilization and condensation processes is smaller than the precision of Pb isotope measurements (better than 60 ppm/a.m.u.). The absence of net fractionation could result from negligible isotope fractionation during Pb volatilization followed by extensive condensation of gaseous Pb, with possibly significant isotopic fractionation at this stage. Although this scenario has to be refined by more direct measurement of the gas phase, and its general applicability tested, it suggests that a small fraction (<10\%) of initially volatilized Pb ultimately escapes to the atmosphere, while the remaining dominant fraction is trapped in sublimates. As sublimates are rapidly dissolved and entrained by runoff, the fumarolic environment appears as a factory efficiently transferring isotopically unfractionated Pb from magmas towards the hydrological system and seawater. Resolving very small isotopic differences between magmas and their gaseous products remains an analytical challenge. High-precision Pb isotope measurements rest not only on instrumental performance but also on high-yield chemistry, as Pb isotopes drastically fractionate (800 ppm/a.m.u.) upon elution on anionic resin. For 50\% Pb recovery, the estimated isotopic bias is plus or minus 60-80 ppm/a.m.u., depending on which of the early (isotopically light) or late (isotopically heavy) Pb fraction is lost. (c) 2012 Elsevier Ltd. All rights reserved
Performance of the CSTR-in-series extractive membrane bioreactor in industrial wastewater treatment
The extractive membrane bioreactor (EMBR) is a treatment method which had demonstrated success in the removal of organic compounds such as phenol, nitrochlorobenzene, dichloroaniline from complex industrial wastewaters that are naturally hostile to bioprocessing (eg. extreme pH and salinity) (Livingston 1993, Brookes and A.G.Livingston 1994). As shown in
Figure, the targeted organics from the feed wastewater are extracted by the membrane into the bioreactor downstream of the membrane while salt and acid/alkaline are retained at the feed side, creating an environment conducive to the bioremoval of organics downstream of the membrane. The biofilm on the downstream side of the membrane surface removes and biodegrades the organics, creating the concentration gradient required to sustain the organic flux across the membrane. In this study, the EMBR is applied for the first time in the CSTR-in-series configuration using in-house hollow fiber membranes (Loh, Zhang et al. 2016) in submerged EMBR systems. Preliminary studies were conducted using a synthetic feed solution comprising of 860 ppm phenol and 5 g/L NaCl. The phenol that diffused across the membranes served as a carbon source for the biofilm downstream of the membrane while additional inorganic nutrients comprising of MgSO4.7H2O, CaCl2.2H2O, KH2PO4, K2HPO4, FeCl3 and NH4Cl were supplied to the bioreactor on a daily basis. At a feed flow rate of 0.86 L/day, the effluent treatment concentration can be as low as 84 ppm (just 10% of the influent). No phenol was detected on the bioreactor side throughout the operation, indicating all phenol was removed by the biofilms on the membrane surface. Our study demonstrates that the EMBR is a promising system that can treat difficult industrial wastewater at source and could potentially reduce costs associated with other treatment strategies (eg. maintenance of activated carbon cartridges). Biofilm characterization results and the performance of the CSTR-in-series EMBR in treatment of actual industrial wastewater will be shared.
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One-loop chiral amplitudes of Moller scattering process
The high energy amplitudes of the large angles Moller scattering are
calculated in frame of chiral basis in Born and 1-loop QED level. Taking into
account as well the contribution from emission of soft real photons the compact
relations free from infrared divergences are obtained. The expressions for
separate chiral amplitudes contribution to the cross section are in agreement
with renormalization group predictions.Comment: 15 pages, 3 figure
Intraoperative Phase Contrast MRI Analysis of Cerebrospinal Fluid Velocities During Posterior Fossa Decompression for Chiari I Malformation
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154938/1/jmri26953_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154938/2/jmri26953.pd
8âYearâOld Boy with Progressive Headache
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99694/1/bpa12074.pd
Soil related constraints for sustainable intensification of cereal-based systems in semi-arid central Tanzania
Nuclear shadowing in polarized DIS on ^6LiD at small x and its effect on the extraction of the deuteron spin structure function g_{1}^{d}(x,Q^2)
We consider the effect of nuclear shadowing in polarized deep inelastic
scattering (DIS) on ^6LiD at small Bjorken x and its relevance to the
extraction of the deuteron spin structure function g_{1}^{d}(x,Q^2). Using
models, which describe nuclear shadowing in unpolarized DIS, we demonstrate
that the nuclear shadowing correction to g_{1}^{d}(x,Q^2) is significant.Comment: 17 pages, 2 figure
Expression of heterogeneous nuclear ribonucleoprotein A2/B1 changes with critical stages of mammalian lung development
Recent reports have demostrated a link between expression of members of the family of heterogeneous nuclear ribonucleoproteins (hnRNPs) and cancer. Overexpression of hnRNP A2/B1 correlated with the eventual development of lung cancer in three different clinical cohorts. We have studied the expression of hnRNP A2/B1 messenger RNA (mRNA) and protein during mammalian development. The expression of hnRNP A2/B1 mRNA and protein are parallel but change dynamically during critical periods in mouse pulmonary development. hnRNP A2/B1 is first detected in the lung in the early pseudoglandular period, peaks at the beginning of the canalicular period, and remains high during the saccular (alveolar) period. In mouse and rat, hnRNP A2/B1 expression is first evident in the earliest lung buds. As lung development progresses, the cuboidal epithelial cells of the distal primitive alveoli show high levels of the ribonucleoprotein, which is almost undetectable in the proximal conducting airways. The expression of hnRNP A2/ B1 is restricted in mature lung. Similar dynamic pattern of expression through lung development was also found in rat and human lung. Upregulated expression of hnRNP A2/B1 at critical periods of lung development was comparable to the level of expression found in lung cancers and preneoplastic lesions and is consistent with hnRNP A2/B1 overexpression playing an oncodevelopmental role
Role of the Delta (1232) in DIS on polarized He and extraction of the neutron spin structure function
We consider the effect of the transitions and in deep inelastic scattering on polarized He on the extraction
of the neutron spin structure function . Making the natural
assumption that these transitions are the dominant non-nucleonic contributions
to the renormalization of the axial vector coupling constant in the A=3 system,
we find that the effect of increases by % in the range , where our considerations are applicable
and most of the data for exist.Comment: 23 pages, 6 figures, revte
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