Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branchingfractions for seven Cabibbo suppressed hadronic weak decays $D^0 \\to K^- K^+$, $\\pi^+ \\pi^-$, $K^- K^+ \\pi^+ \\pi^-$ and $\\pi^+ \\pi^+ \\pi^- \\pi^-$, $D^+ \\to \\bar{K^0} K^+$, $K^- K^+ \\pi^+$ and $\\pi^- \\pi^+ \\pi^+$ are presented.
Measurements of branchingfractions and CP-asymmetries of B^{-} \\rightarrow D^{0}K^{-} modes allow a theoretically-clean extraction of the CKM angle \\gamma. The method proposed by Atwood, Dunietz and Soni (ADS) makes use of a decay chain where color and Cabibbo suppression interfere, which produces large CP-violating asymmetries. The CDF experiment reports the first measurement at a hadron collider of branchingfractions and CP-asymmetries of suppressed B^{-} \\rightarrow D^{0}h^{-} signals, where h is \\pi or K. Using 5.0 fb^{-1} of data we found a combined significance exceeding 5\\sigma and we determined the ADS parameters with accuracy comparable with B-factories.
We review the progress on experimental studies of the non-$D\\bar D$ decays of the $\\psi(3770)$ resonance. With the world average of the observed cross sections for $D\\bar D$ production measured at 3.773 GeV by the MARK-I, MARK-II, BES and CLEO Collaborations, combined together with the cross section for $\\psi(3770)$ production at its peak as well as initial state radiative correction factor, we find that the non-$D\\bar D$ branchingfraction of $\\psi(3770)$ decays is $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(19.8\\pm 1.8 \\pm 5.6)%$, which is consistent within error with $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(14.7\\pm 3.2)%$ measured previously by the BES Collaboration. In addition, a global amplitude analysis of the cross sections for $e^+e^- \\to {\\rm LH}$ (LH= light hadron) measured by the CLEO Collaboration shows that the light hadronbranching ...
By analyzing the $R$ values measured at 68 energy points in the energy region between 3.650 and 3.872 GeV reported in our previous paper, we have precisely measured the mass, the total width, the leptonic width and the leptonic decay branchingfraction of the $\\psi(3770)$ to be ${M}_{\\psi(3770)}=3772.4 \\pm 0.4 \\pm 0.3$ MeV, $\\Gamma_{\\psi(3770)}^{\\rm tot} = 28.6 \\pm 1.2 \\pm 0.2$ MeV, $\\Gamma_{\\psi(3770)}^{ee} = 279 \\pm 11 \\pm 13$ eV and $B[\\psi(3770)\\to e^+e^-]=(0.98\\pm 0.04\\pm 0.04)\\times 10^{-5}$, respectively, which result in the observed cross section $\\sigma^{\\rm obs}[e^+e^-\\to \\psi(3770)]=7.25\\pm 0.27 \\pm 0.34$ nb at $\\sqrt{s}=3772.4$ MeV. We have also measured $R_{\\rm uds}=2.121\\pm 0.023 \\pm 0.084$ for the continuum light hadron production in the region from 3.650 to 3.872 GeV.
The processes psi'-->p pbar pi^0 and psi'-->p pbar eta are studied using a sample of 14 million psi' decays collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider. The branchingfraction of psi'-->p pbar pi^0 is measured with improved precision as (13.2\\pm 1.0\\pm 1.5)\\times 10^{-5}, and psi'-->p pbar eta is observed for the first time with a branchingfraction of (5.8\\pm 1.1\\pm 0.7)\\times 10^{-5}, where the first errors are statistical and the second ones are systematic.
(I)Results are given for photoproduction of the D{sup *} at 103 GeV. Clean signals are seen for the decay D{sup *{+-}} {yields} {pi}{sup {+-}}D{sup 0} with the D{sup 0} decaying into both K{sup {-+}}{pi}{sup {+-}} and K{sup {-+}}{pi}{sup {+-}}{pi}{sup 0}. Analysis of the Dalitz plot for the K{pi}{pi} mode gives branchingfractions (BFs) for K{sup {minus}}{rho}{sup +}, K{sup *{minus}}{pi}{sup +}, and {anti K}{sup *0}{pi}{sup 0} final states. The BF for D{sup 0} {yields} K{sup {minus}}{rho}{sup +}, much lower than a previous result, is in approximate agreement with the value expected for an l=1/2 final state. (II)Inelastic and elastic J/{psi} photoproduction on H is investigated at 103 GeV. The inelastic cross section with E{sub {psi}}/E{sub {gamma}} {lt} 0.9 is significantly lower than the corresponding result for muoproduction on Fe targets, but consistent with second-order perturbative QCD calculation. The mean p{sub +} of inelastic events is ...
Two-phase air-water flows in a microscale fractal-like flow network were experimentally studied and results were compared to predictions from existing macroscale void fraction correlations and flow regime maps. Void fraction was assessed using (1) two-dimensional analysis of high-speed images (direct method) and (2) experimentally determined using gas velocities (indirect method). Fixed downstream-to-upstream length and width ratios of 1.4 and 0.71, respectively, characterize the five-level flow network. Channels were fabricated in a 38 mm diameter silicon disk, 250 {mu}m deep disk with a terminal channel width of 100 {mu}m. A Pyrex top allowed for flow visualization. Superficial air and water velocities through the various branch levels were varied from 0.007 m/s to 1.8 m/s and from 0.05 m/s to 0.42 m/s, respectively. Two-phase flow regime maps were generated for each level of the flow network and are well predicted by the ...
Two-phase air-water flows in a microscale fractal-like flow network were experimentally studied and results were compared to predictions from existing macroscale void fraction correlations and flow regime maps. Void fraction was assessed using (1) two-dimensional analysis of high-speed images (direct method) and (2) experimentally determined using gas velocities (indirect method). Fixed downstream-to-upstream length and width ratios of 1.4 and 0.71, respectively, characterize the five-level flow network. Channels were fabricated in a 38 mm diameter silicon disk, 250 ?m deep disk with a terminal channel width of 100 ?m. A Pyrex top allowed for flow visualization. Superficial air and water velocities through the various branch levels were varied from 0.007 m/s to 1.8 m/s and from 0.05 m/s to 0.42 m/s, respectively. Two-phase flow regime maps were generated for each level of the flow network and are well predicted by the ...
Using 14M $\\psi (2S)$ events collected at BESII, the branchingfraction of $\\psi (2S)\\to \\tau ^{+}\\tau ^{-}$ is measured to be $Br_{\\tau \\tau}=(3.10\\pm 0.21\\pm 0.38)\\times 10^{-3}$, where the first error is statistical and the second is systematic.
Associated production of a baryonic Z' boson with the W boson can account for the excess in Wjj production observed by the CDF collaboration at the Tevatron. We analyze other possible channels of this Z' at the Tevatron and at the LHC, including \\gamma Z' and Z Z' with the Z' -> jj. We show that the chances of confirming this baryonic Z' is better at the Tevatron than at the LHC because of the faster growing backgrounds at the LHC. Unfortunately the current systematic uncertainties of the order of 10% cannot yield any significant excess in both \\gamma Z' and Z Z' channels at the Tevatron and also at the LHC. Nevertheless the search using the b\\bar b decay mode of Z' is much more feasible at the LHC, provided that the branching ratio B(Z' -> b\\bar b) > 0.1. In particular, the W Z' -> l \
We suggest that \\psi (4040) and \\psi (4160) are strong mixtures of ground state hybrid charmonium at \\sim 4.1 GeV and the \\psi (3S) of conventional charmonium. The \\Gamma^{e^+e^-}, masses and total widths of the \\psi(4040) and \\psi(4160) are in accord with this hypothesis. Their hadronic decays are predicted to be dominated by the \\psi (3S) component and hence are correlated. In particular we find a spin counting relation \\Gamma (4160 \\rightarrow D_sD_s^*) \\sim 4 \\Gamma (4040 \\rightarrow D_sD_s) due to their common \\psi(3S) component. For D and D^* production, using \\psi(4040) branching ratios as input, we predict that the decay pattern of the \\psi(4160) will be very different from that of the \\psi(4040). These predictions may be tested in historical data from SPEAR, BES or at future Tau-Charm Factories.
We consider the possibility of "Higgs counterfeits" - scalars that can be produced with cross sections comparable to the SM Higgs, and which decay with identical relative observable branching ratios, but which are nonetheless not responsible for electroweak symmetry breaking. We also consider a related scenario involving "Higgs friends," fields similarly produced through gg fusion processes, which would be discovered through diboson channels WW, ZZ, gamma gamma, or even gamma Z, potentially with larger cross sections times branching ratios than for the Higgs. The discovery of either a Higgs friend or a Higgs counterfeit, rather than directly pointing towards the origin of the weak scale, would indicate the presence of new colored fields necessary for the sizable production cross section (and possibly new colorless but electroweakly charged states as well, in the case of the diboson decays of a Higgs friend). These particles could easily be ...
The decay modes $\\jpsi\\ar\\gamma\\pi^0, \\gamma\\eta$ and $\\gamma\\etap$ are analyzed using a data sample of 58 million $\\jpsi$ decays collected with the BESII detector at BEPC. The branchingfractions are determined to be: $Br(\\jpsi\\ar\\gamma\\pi^0)=(3.13^{+0.65}_{-0.44})\\times10^{-5}$, $Br(\\jpsi\\ar\\gamma\\eta)=(11.23\\pm0.89)\\times10^{-4}$, and $Br(\\jpsi\\ar\\gamma\\etap)=(5.55\\pm0.44)\\times10^{-3}$, where the errors are combined statistical and systematic errors. The ratio of partial widths $\\Gamma(\\jpsi\\ar\\gamma\\etap)/\\Gamma(\\jpsi\\ar\\gamma\\eta)$ is measured to be $4.94\\pm0.40$, and the singlet-octet pseudoscalar mixing angle of $\\eta-\\etap$ system is determined to be $\\theta_{P}=(-22.08\\pm0.81)^{\\circ}$.
Using 14M psi(2S) events taken with the BES-II detector, chi_cJ-->K+K-K+K- decays are studied. For the four-kaon final state, the branchingfractions are B(chi_c0,1,2 -->K+K-K+K-)=(3.47\\pm 0.22\\pm 0.48)\\times 10^{-3}, (0.68\\pm 0.13\\pm 0.10)\\times 10^{-3}, and (1.88\\pm 0.18\\pm 0.28)\\times 10^{-3}. For the \\phi K+K- final state, the branchingfractions, which are measured for the first time, are B(chi_c0,1,2-->\\phi K+K-)=(1.02\\pm 0.22\\pm 0.15)\\times 10^{-3}, (0.44\\pm 0.14\\pm 0.07)\\times 10^{-3}, and (1.46\\pm 0.21\\pm 0.22)\\times 10^{-4}. For the \\phi\\phi final state, B(chi_{c0,2}-->\\phi\\phi)=(0.94\\pm 0.21\\pm 0.14)\\times 10^{-3} and (1.48\\pm 0.26\\pm 0.23)\\times 10^{-3}.
We investigate the possibility of producing the $\\omega\\phi$ threshold enhancement recently observed in the $J\\psi\\to\\gamma X(1812),~X(1812)\\to\\omega\\phi$ at BES by assuming the X(1812) to be a candidate of $(K^{*}\\bar K^{*0})$ molecular state. We evaluate the decay rate of $X(1812)\\to\\eta\\eta', \\eta\\eta, \\omega\\phi, K^+K^-, \\rho^+\\rho^-$, $\\omega\\omega, K^{*+}K^{*-}$ and $\\pi^+\\pi^-$ based on the X(1812) to be a candidate of $(\\ksks)$ molecule. It turns out the X(1812) dominantly decays into $\\eta\\eta'$ and $\\eta\\eta$. These channels are suggested to be the laboratory to test the molecular scenario in experiment. We also evaluate the branchingfraction $Br(X\\to\\omega\\phi)\\simeq 4.60%$. However, the X(1812) has small branchingfractions to decay into other $VV$ or $PP$ final states, from which it seems to be consistent with the experimental observation. In the molecular ...
The Dalitz plot of $\\eta^{\\prime} \\to \\eta \\pi^+ \\pi^-$ decay is studied using $(225.2\\pm2.8)\\times 10^6$ $\\jpsi$ events collected with the BESIII detector at the BEPCII $e^+e^-$ collider. With the largest sample of $\\eta^{\\prime}$ decays to date, the parameters of the Dalitz plot are determined in a generalized and a linear representation. Also the branchingfraction of $\\jpsi \\to \\gamma \\eta^{\\prime}$ is determined to be $(4.84\\pm0.03\\pm0.24)\\times 10^{-3}$, where the first error is statistical and the second systematic.
Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.
This thesis describes the analysis of the semileptonic decay D{sup 0} {yields} {bar K}{sup 0} {pi}{sup -} {mu}{sup +}{nu} using FOCUS data. FOCUS is a fixed target experiment at Fermilab that studies the physics of the charm quark. Particles containing charm are produced by photon-gluon fusion from the collision of a photon beam on a BeO target. The experiment is characterized by excellent vertex resolution and particle identification. The spectrometer consists of three systems for track reconstruction (two silicon systems and one multiwire proportional chamber system) and two magnets of opposite polarity. The polarity of the magnet is such that the events of e{sup +}e{sup -} pairs produced in the target (which constitutes the main background) travel through a central opening in the detectors without interactions. Particle momentum is measured from the deflection angle in the magnets. Three multicell Cerenkov counters are used for charged particle identification (for e, {pi}, K, and ...
Quark-hadron duality addresses some of the most fundamental issues in strong interaction physics, in particular the nature of the transition from the perturbative to non-perturbative regions of QCD. I summarize recent developments in quark-hadron duality in lepton-hadron scattering, and outline how duality can be studied at future high-luminosity facilities such as Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.
After some preliminary comments on prevailing attitudes about tachyons, the author discusses superluminal transformations and the electromagnetic properties of tachyons. Their role in quantum mechanics is examined and a relativistically invariant hadron bootstrap model, which appears to account for many hadron states, is presented. (W.D.L).
We report the first observation of $\\mPJpsi \\to \\mPeta\\mPKst\\mAPKst$ decay in a $\\mPJpsi$ sample of 58 million events collected with the BESII detector. The branchingfraction is determined to be $(1.15 \\pm 0.13 \\pm 0.22)\\times 10^{-3}$. The selected signal event sample is further used to search for the $\\mPY$ resonance through $\\mPJpsi \\to \\mPeta \\mPY, \\mPY\\to\\mPKst\\mAPKst$. No evidence of a signal is seen. An upper limit of \\mathrm{Br}(\\mPJpsi \\to \\mPeta \\mPY)\\cdot\\mathrm{Br}(\\mPY\\to\\mPKst\\mAPKst) < 2.52\\times 10^{-4} is set at the 90% confidence level.
The authors present the results of a search for W{prime} boson decaying to electron-neutrino pairs in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using a data sample corresponding to 205 pb{sup -1} of integrated luminosity collected by the CDF II detector at Fermilab. They observe no evidence for this decay mode and set limits on the production cross section times branchingfraction, assuming the neutrinos from W{prime} boson decays to be light. If they assume the manifest left-right symmetric model, they exclude a W{prime} boson with mass less than 788 GeV/c{sup 2} at the 95% confidence level.
In this paper the basic properties of non-rotating and slowly rotating protoneutron stars in the relativistic mean-field approach are discussed. The equation of state is the main input to the structure equations. The TM1 parameter set extended to the finite-temperature case is used to obtain the mass-radius relation for protoneutron stars. The occurrence of unstable branches in the mass-radius relation are presented. This allows for the existence of distinctively different evolution tracks for protoneutron stars. The low-density protoneutron star configurations are estimated. The stable configurations obtained for fixed lepton number Y{sub L}=0.4 are compared with those obtained for fixed proton fraction Y{sub P}=0.1776. (author)
Based on 58 million J/Psi events collected with the BESII detector at the BEPC, the baryon pair processes J/Psi to $\\Sigma^+ \\bar{\\Sigma}^-$ and J/Psi to $\\Xi^0 \\bar{\\Xi}^0$ are observed for the first time. The branchingfractions are measured to be ${\\cal B}(J/Psi to \\Sigma^+ \\bar{\\Sigma}^-)=(1.50\\pm 0.10\\pm 0.22)\\times 10^{-3}$ and ${\\cal B}(J/Psi to \\Xi^0 \\bar{\\Xi}^0)=(1.20\\pm 0.12\\pm 0.21)\\times 10^{-3}$, where the first errors are statistical and the second ones are systematic.
Upgrading of potato pulp, a byproduct stream from industrial manufacture of potato starch, is important for the continued economic competitiveness of the potato starch industry. The major part of potato pulp consists of the tuber plant cell wall material which is particularly rich in galactan branched rhamnogalacturonan I type pectin. In the work reported here, the release of high-molecular weight pectinaceous dietary fiber polysaccharides from starch free potato pulp was accomplished by use of a multicomponent pectinase preparation from Aspergillus aculeatus (Viscozyme L). The enzyme reaction conditions for the solubilization were optimized via a surface response design to be addition of 0.27% Viscozyme L by weight of potato pulp substrate dry matter, 1h treatment at pH 3.5, 62.5degreeC. ...
Development of the Technology and Control of Electron-Beam Welding Procedure and Production of Full Scale Sector of Endcap CMS Hadron Calorimeter. Preparation for Mass Production.
We report the results of searches for several decay modes of the {tau}-lepton with {ge} 7 pions in the final state using 207 x 10{sup 6} {tau}-pairs collected with the BaBar detector. For the decays with 7 charged pions in the final state we find the following 90% CL upper limits: B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}({pi}{sup 0}){nu}{sub {tau}}) < 3.0 x 10{sup -7}, B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}{nu}{sub {tau}}) < 4.3 x 10{sup -7} and B({tau}{sup -} {yields}) B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}{pi}{sup 0}{nu}{sub {tau}}) < 2.5 x 10{sup -7}. We also search for the decay {tau}{sup -} {yields} 3{pi}{sup -}2{pi}{sup +}2{pi}{sup 0}{nu}{sub {tau}} and report a 90% CL upper limit of < 3.4 x 10{sup -6} for its branchingfraction. Finally, we search for the exclusive final state {tau}{sup -} {yields} 2{sigma}{pi}{sup -}{nu}{sub {tau}} and find a 90% CL upper limit for its ...
A historical summary is made on the measurements concerning the rising total hadron-hadron cross sections at high energies. The first part of this paper concerns the total cross section measurements performed at the Brookhaven, Serpukhov and Fermilab fixed target accelerators; then the measurements at the CERN Intersecting Storage Rings (ISR), and at the CERN and at the Tevatron Fermilab proton-antiproton colliders; finally the cosmic ray measurements at even higher energies. A short discussion on Conclusions and Perspectives follows.
We present a detailed phenomenological study of direct photon production in association with a heavy-quark jet in pA collisions at the Relativistic Heavy Ion Collider (RHIC) and at the Large Hadron Collider (LHC) at next-to-leading order in QCD. The dominant contribution to the cross-section comes from the gluon--heavy-quark (gQ) initiated subprocess, making \\gamma + Q production a process very sensitive to both the gluon and the heavy-quark parton distribution functions (PDFs). Additionally, the RHIC and LHC experiments are probing complementary kinematic regions in the momentum fraction x_2 carried by the target partons. Thus, the nuclear production ratio R^{\\gamma+Q}_{pA} can provide strong constraints, over a broad x-range, on the poorly determined nuclear parton distribution functions which are extremely important for the interpretation of results in heavy-ion collisions.
W and Z bosons are expected to be produced abundantly at the Large Hadron Collider (LHC). This large dataset and the high LHC energy will allow for detailed studies of their properties in a previously unexplored kinematic domain of low parton momentum fraction and high energy scale thus providing, together with the proton-proton nature of the collisions, new constraints on the parton distribution functions and precise tests of perturbative QCD. First determinations of the W -> lnu and Z -> ll (l = e,mu) production cross sections for proton-proton collisions at sqrt(s) = 7 TeV were performed using about 320/nb of data recorded by the ATLAS experiment at the LHC. The results of these measurements for W and Z bosons for proton-proton collisions at sqrt(s) = 7 TeV are presented. In addition ?rst measurements of the ratio between the W and Z/gamma*-cross sections and of the W -> lnu charge asymmetry are also discussed.
Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and B_s systems have stimulated many studies of physics beyond the standard model. We investigate anomalous t W d_j interactions as a possible source of new effects in B_{d,s} - bar B_{d,s} oscillations within a model independent approach based on the assumptions of Minimal Flavor Violation. After matching our effective operators onto the low-energy effective Lagrangian describing B_{d,s} meson mixing and evolving it down to the B-mass scale, we extract the preferred ranges of the anomalous t W d_j interactions at the weak scale. These values are then compared to previously considered constraints coming from the rare radiative B --> X_s gamma decay. Finally, we reconsider the associated effects in the t --> b W decays and find ...
Recent observations of a large excess of cosmic-ray positrons at high energies have raised a lot of interest in leptonic decay modes of dark matter particles. Nevertheless, dark matter particles in the Milky Way halo could also decay hadronically, producing not only a flux of antiprotons but also a flux of antideuterons. We show that for certain choices of parameters the antideuteron flux from dark matter decay can be much larger than the purely secondary flux from spallation of cosmic rays on the interstellar medium, while the total antiproton flux remains consistent with present observations. We show that if the dark matter particle is sufficiently light, the antideuteron flux from dark matter decay could even be within the reach of planned experiments such as AMS-02 or GAPS. Furthermore, we discuss the prospects to observe the antideuteron flux in the near future if the steep rise in the positron fraction reported by the PAMELA collaboration ...
Using $\\gamma \\gamma J/\\psi, J/\\psi \\ra e^+ e^-$ and $\\mu^+ \\mu^-$ events from a sample of $14.0\\times 10^6$ $\\psip$ decays collected with the BESII detector, the branchingfractions for $\\psip\\ra \\pi^0\\J$, $\\eta\\J$, and $\\psi(2S)\\ar\\gamma\\chi_{c1},\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi$ are measured to be $B(\\psip\\ra \\pi^0\\J) = (1.43\\pm0.14\\pm0.13)\\times 10^{-3}$, $B(\\psip\\ra \\eta\\J) = (2.98\\pm0.09\\pm0.23)%$, $B(\\psi(2S)\\ar\\gamma\\chi_{c1}\\ar\\gamma\\gamma\\jpsi) = (2.81\\pm0.05\\pm 0.23)%$, and $B(\\psi(2S)\\ar\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi) = (1.62\\pm0.04\\pm 0.12)%$.
Measurements of gamma-ray spectra, following the thermal neutron fission of "2"3"5U have been made using a high purity germanium detector at the University of Massachusetts Lowell (UML) Van de Graaff facility. The gamma spectra were measured at delay times ranging from 0.2 s to nearly 10000 s following the rapid transfer of the fission fragments with a helium-jet system. On the basis of the known gamma transitions, forty isotopes have been identified and studied. By measuring the relative intensities of these transitions, the relative yields of the various precursor nuclides have been calculated. The results are compared with the recommended values listed in the ENDF/B-VI fission product data base (for the lifetimes and the relative yields) and those published in the Nuclear Data Sheets (for the beta branching ratios). This information is particularly useful for the cases of short-lived fission products with lifetimes of the order of fractions ...
The e{sup +}e{sup -}{yields}pp cross section is determined over a range of pp masses, from threshold to 4.5 GeV/c{sup 2}, by studying the e{sup +}e{sup -}{yields}pp{gamma} process. The data set corresponds to an integrated luminosity of 232 fb{sup -1}, collected with the BABAR detector at the PEP-II storage ring, at an e{sup +}e{sup -} center-of-mass energy of 10.6 GeV. The mass dependence of the ratio of electric and magnetic form factors, G{sub E}/G{sub M}, is measured for pp masses below 3 GeV/c{sup 2}; its value is found to be significantly larger than 1 for masses up to 2.2 GeV/c{sup 2}. We also measure J/{psi}{yields}pp and {psi}(2S){yields}pp branchingfractions and set an upper limit on Y(4260){yields}pp production and decay.
The authors report on a search for pair production of first-generation scalar leptoquarks (LQ) in p{bar p} collisions at {radical}s = 1.96 TeV using an integrated luminosity of 252 pb{sup -1} collected at the Fermilab Tevatron collider by the D0 detector. They observe no evidence for LQ production in the topologies arising from LQ{ovr LQ} {yields} eqeq and LQ{ovr LQ} {yields} eqvq, and derive 95% C.L. lower limits on the LQ mass as a function of {beta}, where {beta} is the branchingfraction for LQ {yields} eq. The limits are 241 and 218 GeV/c{sup 2} for {beta} = 1 and 0.5, respectively. These results are combined with those obtained by D0 at {radical}s = 1.8 TeV, which increases these LQ mass limits to 256 and 234 GeV/c{sup 2}.
Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the h_b(1P) spin-singlet partner of the P-wave chi_b(1P) states in the sequential decay Upsilon(3S) --> pi0 h_b(1P), h_b(1P) --> gamma eta_b(1S). We observe an excess of events above background in the distribution of the recoil mass against the pi0 at mass 9902 +/- 4 (stat.) +/- 1 (syst.) MeV/c^2. The width of the observed signal is consistent with experimental resolution, and its significance is 3.0 sigma, including systematic uncertainties. We obtain the value (3.7 +/- 1.1 (stat.) +/- 0.7 (syst.))x 10^{-4} for the product branchingfraction BF(Upsilon(3S) --> pi0 h_b) x BF(h_b --> gamma eta_b).
Using 347.5 fb-1 of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244*10^3 signal events for the D+ --> K- pi+ e+ nu_e decay channel are analyzed. This decay mode is dominated by the \\bar{K}^*(892)^0 contribution. We determine the \\bar{K}^*(892)^0 parameters: m_{K^*(892)^0}=(895.4 +- 0.2 +- 0.2) MeV/c^{2}, \\Gamma^0_{K^*(892)^0}=(46.5 +- 0.3 +- 0.2) MeV/c^{2} and the Blatt-Weisskopf parameter $r_{BW}=2.1 +- 0.5 +- 0.5 (GeV/c)^{-1} where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q^{2}=0 (r_{V} = V(0) / A_{1}(0)=1.463 +- 0.017 +- 0.031, r_{2} = A_{2}(0) / A_{1}(0) = 0.801 +- 0.020 +- 0.020) and the value of the axial-vector pole mass parameterizing the q^2 variation of A_{1} and A_{2}: m_{A}=(2.63 +- 0.10 +- 0.13) GeV/c^{2}. The S-wave fraction is equal to (5.79 +- 0.16 +- 0.15)%. ...
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
A method to identify hadronic molecules in the particle spectrum is reviewed and the conditions for its applicability discussed. Special emphasis is put on the discussion of molecule candidates in the baryon spectrum. (orig.)
In this study we consider relations between companies in Poland taking into account common branches they belong to. It is clear that companies belonging to the same branch compete for similar customers, so the market induces correlations between them. On the other hand two branches can be related by companies acting in both of them. To remove weak, accidental links we shall use a concept of threshold filtering for weighted networks where a link weight corresponds to a number of existing connections (common companies or branches) between a pair of nodes.
Time-odd parton distribution functions in a Drell-Yan process are here studied by examining the evolution of the internal statistical properties of the interacting hadrons. Time-odd functions are shown to be a signature of the irreversible process in which a hadronic state characterized by long range correlation properties (hadronic phase) decays to produce a cloud of independent partons (partonic phase) because of initial/final state interactions. The relevant considered variable is the rate of increase of the entropy of the hadronic system. This quantity is shown to be roughly equal to the decay rate of the hadronic state. Conditions for getting a leading twist time-odd effect are established on this basis. Last, the relevant case of a large entropy increase associated with transverse-dominated initial/final state interactions is analyzed.
This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to ...
Using EAS data from the EAS-EXC group (EAS plus hadronic calorimeter and nuclear emulsion-X chamber hybrid experiment) on Mount Chacaltaya during the 1990's the fractal properties of the energetic cosmic ray fluxes was investigated. A discrimination in the hadron content of the energetic primaries furnishes two different data samples, the total EAS fluxes and the hadron-less fluxes. The sidereal diurnal variation of the hadron-less EAS time variation shows values of 0.5% with a phase at about 2.29 hr sidereal time. With the help of the Crassberger Procaccia algorithm the fractal dimensions have been investigated of, on the one hand, the differences in arrival times of the hadron-less showers and on the other hand the EAS fluxes time series with an integration time of five min. The obtained fractal dimensions show inconclusive evidence of continuous chaotic component in the ...
A series of branched alkylbenzene ranging from C15 to C19 with several isomers (2?5) at each carbon number were identified in sediments from the Dongsheng sedimentary uranium ore deposits, Ordos Basin, China. The distribution patterns of the branched alkylbenzenes show significant differences in the sample extracts. The branched alkylbenzenes from organic-rich argillites and coals range from C15 to C19 homologues, in which the C17 or C18 dominated. On the other hand, the C19 branched alkylbenzenes dominated in the sandstone/siltstone extracts. The obvious differences of the branched alkylbenzene distributions between the uranium-host sandstones/siltstones and the interbedded barren organic-rich mudstones/coals probably indicate their potential use as biological markers associated with part...
The Measurements and Characterization Branch actively supports the advancement of DOE/NREL goals for the development and implementation of the solar photovoltaic (PV) technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility that Is capable of providing information on the full range of PV components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of Pv technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. The Measurements and Characterization Branch encompasses seven coordinated research groups, providing integrated research and development ...
... of the utility of the terminal outcomes, ... Other stochastic topics, such as random walks, branching ... find special uses, particularly in queueing theory ...
Future insertion quadrupoles with large apertures and high gradients will be required for the Phase II luminosity upgrade (10{sup 35} cm{sup -2}s{sup -1}) of the Large Hadron Collider (LHC). Although improved designs, based on NbTi, are being considered as an intermediate step for the Phase I upgrade, the Nb{sub 3}Sn conductor is presently the best option that meets the ultimate performance goals for both operating field and temperature margin. As part of the development of Nb{sub 3}Sn magnet technology, the LHC Accelerator Research Program (LARP) developed and tested several 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupoles. The first two series of magnet used OST MJR 54/61 (TQ01 series) and OST RRP 54/61 (TQ02 series) strands. The third series (TQ03) used OST RRP 108/127 conductor. The larger number of sub-elements and the consequent reduction of the effective filament size, together with an increased fraction of copper and a lower Jc were ...
Asymptotic giant branch stars are red supergiant stars of low-to-intermediate mass. This class of stars is of particular interest because many of these stars can have nuclear processed material brought up repeatedly from the deep interior to the surface where it can be observed. A review of recent theoretical and observational work on stars undergoing the asymptotic giant branch phase is presented. 41 refs.
The condition for obtaining a calorimetric response linear with energy for hadronic showers and an energy resolution that improves as the incident energy increases is the equalization of the electromagnetic (e) and the hadronic (#pi#) signal responses. This equalization is obtained by exploiting a local hardening effect realized through the insertion of low-Z thin plates between the high-Z absorbers and the active material in a hadronic calorimeter with silicon readout. This effect, which allows the reduction of the calorimeter response to the electromagnetic component of the incoming hadronic showers, has been investigated for different low-Z materials. The relevance of some aspects of this study to the radiation hardness of the calorimeters is also addressed. (orig.).
In a series of recent papers, Corben recovered various properties of many hadronic resonances by considering them as compounds of a bradyon and of one (or more) tachyons. In this note it is explained why that success follows from considering the tachyon four-momenta orthogonal to the bradyon one, and why, in such a case, the bradyon and tachyons can be formally dealt with as non-interacting even when they keep participating in the ''self-trapping''. Finally an attempt is made to understand (on the basis of the model by Caldirola, Pavsic and Recami where hadrons are considered as ''strong black-holes'') why in general those compound hadrons decay and why in this decay the trapped tachyons are, quantum-mechanically, emitted in the corresponding bradyonic form.
The evaluation of calculated values determined by means of the equations given in the TRD 300/301 standard resulted in two nomographs by which it is possible to find the theoretical wall thickness of cylinder shells without cutouts and branches as well as cylinder shells with an inclined or vertical single branch without additional thickening. The equations for the calculation of cylinder shells with an inclined single branch according to TRD 301 having only an iterative solution, the nomographs will be a considerable help for the engineering work. The determination of the theoretical wall-thickness from the nomographs is demonstrated by means of examples.
Using the peptide hormone glucagon and Ab(1-40) as model systems, we have sought to elucidate the mechanisms by which fibrils grow and multiply. We here present real-time observations of growing fibrils at a single-fibril level. Growing from preformed seeds, glucagon fibrils were able to generate new fibril ends by continuously branching into new fibrils. To our knowledge, this is the first time amyloid fibril branching has been observed in real-time. Glucagon fibrils formed by branching always grew in the forward direction of the parent fibril with a preferred angle of 35-40degree. Furthermore, branching never occurred at the tip of the parent fibril. In contrast, in a previous study by some of us, Ab(1-40) fibrils grew exclusively by elongation of preformed seeds. Fibrillation kinetics i...
This study reports the observation of the decays B{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -} and B{sup 0}{yields}D{sup (*)-}K{sup +} in a sample of 230 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring, located at the Stanford Linear Accelerator Center. The branchingfractions {beta}(B{sup 0} {yields} D{sup +}{sub S}{pi}{sup -}) = (1.3 {+-} 0.3 (stat) {+-} 0.2 (syst)) x 10{sup -5}, {beta}(B{sup 0} {yields} D{sup +}{sub S}K{sup +}) = (2.5 {+-} 0.4 (stat) {+-} 0.4 (syst)) x 10{sup -5}, {beta}(B{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -}) = (2.8 {+-} 0.6 (stat) {+-} 0.5 (syst)) x 10{sup -5}, and {beta}(B{sup 0}{yields}D{sup (*)-}K{sup +}) = (2.0 {+-} 0.5 (stat) {+-} 0.4 (syst)) x 10{sup -5} are measured. The significance of the measurements to differ from zero are 5, 9, 6, and 5 standard deviations, respectively. This is a first observation of the ...
We study the processes gamma gamma -> K^0_S K+/- pi-/+ and gamma gamma -> K+ K- pi+ pi- pi0 using a data sample of 519.2 fb-1 recorded by the BaBar detector at the PEP-II asymmetric-energy e+e- collider at center-of-mass energies near the Upsilon(nS) (n = 2,3,4) resonances. We observe the eta_c(1S), chi_c0(1P), chi_c2(1P), and eta_c(2S) resonances produced in two-photon interactions and decaying to K+ K- pi+ pi- pi0, with significances of 18.1, 5.7, 5.2, and 5.3 standard deviations (including systematic errors), respectively. We measure the eta_c(2S) mass and width in K^0_S K+/- pi-/+ decays, m(eta_c(2S))=3638.5 +/- 1.5 +/- 0.8 MeV/c^2 and Gamma(eta_c(2S)) = 13.4 +/- 4.6 +/- 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We search for the Z(3930) resonance and find no significant signal. We also provide the two-photon width times branchingfraction values for the observed resonances.
We report a study of $B\\to (J/\\psi \\gamma) K$ and $B\\to (\\psi' \\gamma)K$ decay modes using $772\\times 10^{6}$ $B\\bar{B}$ events collected at the \\Upsilon(4S)$ resonance with the Belle detector at the KEKB energy-asymmetric $e^+ e^-$ collider. We observe $X(3872) \\to J/\\psi \\gamma$ and report the first evidence for $\\chi_{c2} \\to J/\\psi \\gamma$ in $B\\to (X_{c\\bar{c}}\\gamma) K$ decays, while in a search for $X(3872) \\to \\psi' \\gamma$ no significant signal is found. We measure the branchingfractions, $\\mathcal{B}(B^{\\pm} \\to X(3872) K^{\\pm}) \\mathcal{B}(X(3872) \\to J/\\psi\\gamma)$ $=$ $(1.78^{+0.48}_{-0.44}\\pm 0.12)\\times 10^{-6}$, $\\mathcal{B} (B^{\\pm} \\to\\chi_{c2} K^{\\pm})$$=$ $(1.11^{+0.36}_{-0.34} \\pm 0.09) \\times 10^{-5}$, $\\mathcal{B}(B^{\\pm} \\to X(3872) K^{\\pm}) \\mathcal{B}(X(3872) \\to \\psi'\\gamma)$ $<$ $3.45\\times 10^{-6}$ (upper limit at 90% C.L.) and also provide upper limits for other ...
Radioiodinated 15-(p-iodophenyl)-3,3-dimethylpentadecanoic acid (DMIPP) has been prepared as a new terminal iodophenyl-substituted fatty acid containing dimethyl-branching at the beta-position. Iodine-125-labeled DMIPP showed rapid, high myocardial uptake (min, mean % injected dose/g) in fasted rats (5, 4.67; 30, 5.06; 60, 4.79; 120, 4.37), and also exhibited high heart:blood ratios (min, ratio) 5, 3:1; 30, 12:1; 60, 12:1; 120, 13:1. These data demonstrate an unanticipated much longer myocardial residence time with DMIPP (+/sub 1/2/ 7-8 h) than observed with either the 3-monomethyl (BMIPP) analogue (+/sub 1/2/ 30-45 min) or the rapidly metabolized straight-chain (IPP) analogue (+/sub 1/2/ 10-15 min). The (/sup 123/I)DMIPP is thus an excellent candidate for clinical evaluation of regional fatty acid metabolism under conditions where the uptake of energy substrates can be assessed independent of regional blood delivery. Studies with the new activated carbon-based ...
We report the first observation of the radiative decay B^0 -> \\phi K^0 \\gamma using a data sample of 772 x 10^6 B B-bar pairs collected at the \\Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. We observe a signal of 37+/-8 events with a significance of 5.4 standard deviations including systematic uncertainties. The measured branchingfraction is ${\\cal B}(B^0 -> \\phi K^0 \\gamma) = (2.74\\pm 0.60 \\pm 0.32) \\times 10^{-6}$, where the uncertainties are statistical and systematic, respectively. We also report the first measurements of time-dependent CP violation parameters: ${\\mathcal S}_{\\phi K_S^0 \\gamma} = +0.74^{+0.72}_{-1.05} (stat)^{+0.10}_{-0.24} (syst)$ and ${\\mathcal A}_{\\phi K_S^0 \\gamma} = +0.35 +/- 0.58 (stat)^{+0.23}_{-0.10} (syst)$. Furthermore, we measure ${\\mathcal B}(B^+ -> \\phi K^+ \\gamma) = (2.48 +/- 0.30 +/- 0.24) x 10^{-6}$, ${\\mathcal A}_{CP} = -0.03 +/- ...
The renewed CDF II experiment recently re-started data taking. The data collected lately already provides insight in the heavy flavor capabilities of this p{bar p} experiment. As a benchmark of these possibilities we present two preliminary results: the measurement of the branchingfractions BR(D{sup o} {yields} {pi}{sup +}{pi}{sup -}) and BR(D{sup o} {yields} K{sup +}K{sup -}) relative to BR(D{sup o} {yields} K{sup {+-}} {pi}{sup {-+}}) and the measurement of the invariant mass difference between D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}, {phi} {yields} K{sup +}K{sup -} and D{sup {+-}} {yields} {phi}{pi}{sup {+-}}, {phi} {yields} K{sup +}K{sup -}. The preliminary results are BR(D{sup o} {yields} {pi}{sup +}{pi}{sup -})/BR(D{sup o} {yields} K{sup {+-}} {pi}{sup {-+}}) = 3.37 {+-} 0.20(stat) {+-} 0.16(sys)%, BR(D{sup o} {yields} K{sup +}K{sup -})/BR(D{sup o} {yields} K{sup {+-}} {pi}{sup {-+}}) = 11.17 {+-} 0.98(sys) % and {Delta}m (D{sub ...
I report on a lattice computation of the energy of a system of two light quarks and two static antiquarks as a function of the separation of the static antiquarks. In terms of hadrons such a system corresponds to a pair of B mesons and its energy to the hadronic potential. I present selected results for different isospin, spin and parity combinations of the individual B mesons mainly focusing on those channels relevant to determine, whether two B mesons may form a bound tetraquark state.
Peak at 60 deg in angular proton distribution in inelastic pion-carbon interactions is interpreted as generation of Cherenkov gluon radiation in flucton, passing into the shock wave with successive nucleus decay. Investigation of hadron-nuclear interactions with anomalous peak in angular proton distribution can be used as additional means for study both of flucton and mechanism of hadron-nuclear interactions. 5 refs.
We discuss the consequence of local duality for elastic scattering, and derive a model-independent equation between structure functions at x ? 1 and elastic electromagnetic form factors. Then the electromagnetic form factors of proton are discussed using the quark-hadron duality theory. We also debate the form factor of proton in a bound state. It may be an effective approach to study the form factor of proton in media.
Two Brucella fractions, the murein-linked fraction PI and the murein-free fraction SF, behave as in vitro adjuvants for primary anti-sheep erythrocyte responses: added to Mishell and Dutton-type cultures...Full Text Available
Development of an assessment framework and indicators can be used to evaluate effectiveness of wetland restoration. Example of these include index of biotic integrity and the hydrogeomorphic method. Both approaches provide qualitative ranks. We propose a new method based on the EPA wetland research program. Similar to other methods, indexes are compared to reference communities; however, the comparisons are quantitative. In this paper we discuss the results of our framework using the Pen Branch riparian wetland system as an example.
Challenges of robotic cars, sponsored by the Defense Advanced Research Projects Agency (DARPA) of the U.S. Defense Department. Carroll Cordes, recently retired USGS branch chief,...
vetted educational resources. (Gregory Smith, Lafayette, La., 337-266-8501) Award for DARPA Competition: Scott Wilson, spatial analysis branch chief at the USGS National Wetlands...
This Resource Letter provides a guide to the literature on Quantum Chromodynamics (QCD), the relativistic quantum field theory of the strong interactions. Journal articles, books, and other documents are cited for the following topics: quarks and color, the parton model, Yang-Mills theory, experimental evidence for color, QCD as a color gauge theory, asymptotic freedom, QCD for heavy hadrons, QCD on the lattice, the QCD vacuum, pictures of quark confinement, early and modern applications of perturbative QCD, the determination of the strong coupling and quark masses, QCD and the hadron spectrum, hadron decays, the quark-gluon plasma, the strong nuclear interaction, and QCD's role in nuclear physics. The letter {E} after an item indicates elementary level or material of general interest to persons becoming informed in the field. The letter {I}, for intermediate level, indicates material of a somewhat more specialized nature, ...
We present a phenomenological model of the quark-hadron transition in neutrino-nucleon scattering. Using recently extracted weak nucleon transition form factors, we investigate the extent to which local and global quark-hadron duality is applicable in the neutrino F{sub 1}, F{sub 2} and F{sub 3} structure functions, and contrast this with duality in electron scattering. Our findings suggest that duality works relatively well for neutrino-nucleon scattering for the F{sub 2} and F{sub 3} structure functions, but not as well for F{sub 1}. We also calculate the quasi-elastic, resonance and deep inelastic contributions to the Adler sum rule, and find it to be satisfied to within 10% for 0.5 < Q{sup 2} < 2 GeV{sup 2}.
Event generators that handle neutrino-nucleon interaction have been developed for the FLUKA code [1]. In earlier FLUKA versions only quasi-elastic (QEL) interactions were included, and the code relied on external event generators for the resonance (RES) and deep inelastic scattering (DIS). The new DIS+RES event generator is fully integrated in FLUKA and uses the same hadronization routines as those used for simulating hadron-nucleon interactions. Nuclear effects in neutrino-nucleus interactions are simulated within the same framework as in the FLUKA hadron-nucleus interaction model (PEANUT), thus profiting from its detailed physics modelling and longstanding benchmarking. The generators are available in the standard FLUKA distribution. They are presently under development and several improvements are planned to be implemented. The physics relevant to the neutrino-nucleon interactions and the results of comparisons with ...
The US Department of the Army, Baltimore District Corps of Engineers, oversees a long-term monitoring study to assess and evaluate effects of the Jennings-Randolph reservoir on biota in the North Branch Potomac River. The reservoir was intended, in part, to mitigate effects of acid mine drainage originating in upstream and headwater area. The present study assessed recovery of benthos and fish in this system, six years after completion of the reservoir. Higher pH and lower iron and sulfate concentrations were observed upstream of the reservoir compared to preimpoundment conditions, suggesting better overall water quality in the upper North Branch. Water quality improved slightly directly downstream of the reservoir. However, the reservoir itself was poorly colonized by macrophytes and benthic organisms, and plankton composition suggested either metal toxicity and/or nutrient limitation. One large tributary to the North ...
This paper reports the results of in situ observation of fatigue crack growth in a ferrite?pearlite steel. Stress intensity factor range (?K) decreasing/increasing and constant-?K fatigue tests have been carried out. In banded pearlite orientation, intense crack branching was observed which leads to fatigue crack retardation. Crack closure during the test was monitored to understand the fatigue crack growth behaviour.
The theoretical evolution of a horizontal branch star of Population II is followed through the helium burning in the core phase and is compared with the results given by other investigators. The m- fluence of different physics and interpolation schemes in the opacity tables is discussed. Some thoughts are given on the explanation of the erratic period variations observed in some of the RR Lyrae variables in the globular clusters. (auth)
Primary dendrite spacings and side-branch coarsening kinetics were examined in specimens of the single-crystal multicomponent commercial superalloy PWA-1480, which were directionally solidified in a psoitive thermal gradient. The experimentally observed dependence of primary dendrite spacings and side-branch coarsening kinetics on growth rate and thermal gradient were in agreement with the behavior predicted by analytical models developed for binary alloys. (orig.).
"Force20 networks, the pioneer in building and securing reliable networks, today announced that the University of Tennessee physics department has deployed the C300 resilient switch to analyze data form CERN's Large Hadron Collider." (1/2 page)
A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant {alpha}{sub s}(M{sup 2}{sub Z}). We also discuss the impact of these quantities on precision observables at hadron colliders. (orig.)
When it was first developed, the standard model predicted a collection of particles, and thanks to more and more powerful colliders, physicsists have been able to find them all except one: the Higgs-Boson.
The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10{sup -15} cm. (orig./HSI).
On the basis of the phenomenological model for baryon resonance production in lepton nucleon and lepton nucleus scattering we investigate to what extent quark hadron duality is applicable to the neutrino structure functions and how it compares with duality in electron scattering.
The HARP experiment at CERN is performing extensive measurements of hadron production cross sections and secondary particle yields, in the momentum range 1.5-15 GeV/c, over the full solid angle and using a large set of cryogenic and solid targets. First measurements of hadron production cross-sections in the forward region are reported using an aluminium target 5% of an interaction length thick and a proton beam of 12.9 GeV/c. A preliminary analysis in the large angle region of elastic scattering events produced with the cryogenic hydrogen target at 3 GeV/c beam momentum is also presented.
I review recent developments in quark-hadron duality in inclusive electron-nucleon scattering. Matrix elements of twist-4 operators extracted from moments of the spin-dependent g1 structure function suggest that duality violating higher twists are small above Q2 {approx} 1 GeV2. The x dependence of local duality is analyzed within a quark model framework, and mechanisms are identified for spin-flavor symmetry breaking which underpin the behavior of structure functions at large x.
The 'elementary' particle physics began in 1935, when Hideki Yukawa published his pioneering pi-meson theory, and the problem of strong interaction was finally solved 40 years later by the establishment of the Standard Model. The composite models of hadrons by the Sakata school and Sin-itiro Tomonaga's renormalization theory for quantum electrodynamics played essential roles for finding this beautiful solution. It is really surprising that it took only 40 years to solve such desperately difficult problem. The 'elementary' particle physics then split into two new fields, quark-hadron physics' and 'unified (ultimate) theory of particle physics', which are now 30 years old already. (author)
Recent developments in the physical model of 1 MeV to 100 TeV hadron and lepton interactions with nuclei and atoms are described. These include a new nuclear cross section library, a model for soft pion production, the cascade-exciton model, the dual parton model, deuteron-nucleus and neutrino-nucleus interaction models, detailed description of mu, pi and anti p absorption and a unified treatment of muon and charged hadron electromagnetic interactions with matter. New algorithms are implemented into the MARS13(98) Monte Carlo code and benchmarked against experimental data. The code capabilities to simulate cascades and generate a variety of results in complex media have been also enhanced.
We calculate the normalized factorial moments of multiplicity distributions through three models for elastic hadron scattering (Chou-Yang, Henzi-Valin and Menon-Pimentel). Connections between the moments and the inelastic overlap function and/or eikonal function are obtained by means of an impact parameter representation for the multiplicity distribution. The predictions are compared with experimental data on factorial moments from both inelastic and non-single-diffractive events. The model results present best agreement with the inelastic events and data favour the model by Henzi and Valin. (author)
The paper describes an application of the tree classification method Random Forest (RF), as used in the analysis of data from the ground-based gamma telescope MAGIC. In such telescopes, cosmic gamma-rays are observed and have to be discriminated against a dominating background of hadronic cosmic-ray particles. We describe the application of RF for this gamma/hadron separation. The RF method often shows superior performance in comparison with traditional semi-empirical techniques. Critical issues of the method and its implementation are discussed. An application of the RF method for estimation of a continuous parameter from related variables, rather than discrete classes, is also discussed.
The authors present a measurement of the B{sub s}{sup 0} meson lifetime using fully and partially reconstructed hadronic decays B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}(X) followed by D{sub s}{sup -} {yields} {phi}{pi}{sup -}. The data sample was recorded with the CDF II detector at the Fermilab Tevatron and corresponds to an integrated luminosity of 1.3 fb{sup -1} from p{bar p} collisions at {radical}s = 1.96 TeV.
\\lhcb is one of the four major experiments at the Large Hadron Collider (\\lhc) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavour hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiments. In this article, the \\lhcb prospects for such measurements with exclusive decays of the type $B \\to \\Xs \\gamma$ and $B \\to X_{s} l^{+} l^{-}$ are presented.
LHC$b$ is one the four major experiments at the Large Hadron Collider (LHC) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavor hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiment. In this article, the LHC$b$ prospects for such measurement with exclusive decays of the type $B \\to X_s\\gamma$ and $B\\to X_sl^+l^-$ are presented.
Biosynthesis of hemoglobin and some of its electrophoretic fractions in red cells of peripheral blood and spleen of irradiated (650 R) rats has been studied. Hemoglobin synthesis is found to be most drastically inhibited in the first and second fractions on the first and eighth days after irradiation and in the fifth and sixth fractions on the eighth day (less expressed). The synthesis is restored on the twelfth day, the process under study proceeding more slowly in the above-mentioned fractions than in others. In the course of radiation sickness, the biosynthesis of certain hemoglobin fractions varies differently in the hemoglobin-synthesizing cells of peripheral blood than in the cells of spleenic erythroid series.
BackgroundThe use of fractionated stereotactic radiotherapy (fsrt) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance....Full Text Available
This paper presents a prescriptive account of diagnostic problem solving, or diagnosis, in quality and process control. This paper identifies a general strategy, named branch-and-prune, whose manifestations can be found in disciplines such as medical diagnosis, troubleshooting of devices, and model-based diagnosis in artificial intelligence. The work aims to offer a clear conceptualization of this strategy, based on the notions of structures for the search space, and constraints to the cause's nature.The idea is to treat the search space of candidate explanations as a tree structure, in which general and high-level causal directions are branched into more specific and detailed explanations. Constraints eliminate all but a few branches (pruning), which are explored in more detail. We enumer...
The determination of Li and proton-capture element abundances in globular cluster (GC) giants allows us to constrain several key questions on the multiple population scenarios in GCs, from formation and early evolution to pollution and dilution mechanisms. In this Letter, we present our results on Li abundances for a large sample of giants in the intermediate-metallicity GC NGC 6121 (M4), for which Na and O have been already determined by Marino et al. The stars analyzed are both below and above the red giant branch bump luminosity. We found that the first and second generation stars share the same Li content, suggesting that a Li production must have occurred. This provides strong observational evidence supporting the scenario in which asymptotic giant branch stars are GC polluters.
The decay psi(2S)-->K_S K_L is observed for the first time using psi(2S) data collected with the Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC); the branching ratio is determined to be B(psi(2S)-->K_S K_L) = (5.24\\pm 0.47 \\pm 0.48)\\times 10^{-5}. Compared with J/psi-->K_S K_L, the psi(2S) branching ratio is enhanced relative to the prediction of the perturbative QCD ``12%'' rule. The result, together with the branching ratios of psi(2S) decays to other pseudoscalar meson pairs (\\pi^+\\pi^- and K^+K^-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.
A phenomenological analysis of lifetimes of bottom and charmed hadrons within the framework of the heavy quark expansion is performed. The baryon matrix element is evaluated using the bag model and the nonrelativistic quark model. We find that bottom-baryon lifetimes follow the pattern #tau#(#OMEGA#_b)#approx =##tau#(#XI#_b"-)>#tau#(#LAMBDA#_b)#approx =##tau#(#XI#_b"0). However, neither the lifetime ratio #tau#(#LAMBDA#_b)/#tau#(B_d) nor the absolute decay rates of the #LAMBDA#_b baryon and B mesons can be explained. One way of solving both difficulties is to allow the presence of linear 1/m_Q corrections by scaling the inclusive nonleptonic width with the fifth power of the hadron mass m_H__Q rather than the heavy quark mass m_Q. The hierarchy of bottom baryon lifetimes is dramatically modified to #tau#(#LAMBDA#_b)>#tau#(#XI#_b"-)>#tau#(#XI#_b"0)>#tau#(#OMEGA#_b): The longest-lived #OMEGA#_b among bottom baryons in the OPE ...
The phosphatidylinositol pathway is implicated in the regulation of numerous cellular functions and responses to extracellular signals. An important branching point in the pathway is the phosphorylation...Full Text Available
The mammary gland is a complex tissue comprised of a branching network of ducts embedded within an adipocyte-rich stroma. The ductal epithelium is a bi-layer of luminal and myoepithelial cells, the...Full Text Available
BackgroundIn 1998, the U.K. National Health Service Information for Health Strategy proposed the implementation of a National electronic Library for Health...Full Text Available
This work describes the synthesis and characterization of novel thermoresponsive highly-branched polyamidoamine-polyethylene glycol-poly (D, L-lactide) (PAMAM-PEG-PDLLA) core-shell nanoparticles....Full Text Available
The purpose of the piezometer network is to establish baseline hydraulic head data for the water table aquifer at the F- and H-Area seeplines prior to startup of the groundwater extraction/injection remediation system.
In the presence of electrochemical energy, several branched-chain neutral and acidic amino acids were found to accumulate in membrane vesicles of Bacillus stearothermophilus. The membrane vesicles contained...Full Text Available
Malnutrition is common among older persons, with important consequences increasing frailty and morbidity and reducing health expectancy. On the contrary, calorie restriction (CR, a low-calorie dietary...Full Text Available
Sep 28, 2011 ... Description: Four Populus clones were grown in central Missouri for 2 years at 1 x 1 m spacing to study total biomass production on floodplain ...
US Army casualty deaths in the Republic of Vietnam were analyzed to provide information on wound ballistics that may be used by interested branches of the services on the subjects of casualty reduction, wounding, mechanisms, and evaluation of hostile weap...
Over the last century, anatomical studies have shown that the cerebral cortex can be subdivided into structurally distinct regions, giving rise to a new branch of neuroanatomy: ‘architectonics’....Full Text Available
This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.
We propose a simple and accurate method to evaluate the outage probability at the output of arbitrarily fading L-branch diversity combining receiver. The method is based on the saddlepoint approximation, which only requires the knowledge of the moment generating functions of the signal-to-noise ratio at the output of each diversity branch. In addition, we show that the obtained results reduce to closed-form expressions in many particular cases of practical interest. Numerical results illustrate a very high accuracy of the proposed method for practical outage values and for a large mixture of fading and system parameters.
The branching ratio of J/psi-->K_S K_L is measured with improved precision to be B(J/psi-->K_S K_L) = (1.82\\pm 0.04\\pm 0.13)\\times 10^{-4}. using J/psi data collected with the Beijing Spectrometer (BESII) at the Beijing Electron-Positron Collider. This result is used to test the perturbative QCD ``12%'' rule between psi(2S) and J/psi decays and to investigate the relative phase between the three-gluon and one-photon annihilation amplitudes in J/psi decays.
During the operation of Daya Bay Nuclear Power Station, some little branches of secondary system were with great vibration and even some of them cracked due to the great vibration that may cause some effect on the safety of the power station. This paper performed analysis and evaluation to the eight systems of Daya Bay Nuclear Power Station based on the vibration test results from the examination of the safety during ten years, and the list of the sensitive piping and suggestion for modification were presented based on the analysis results. (authors)
This is a report of extraction and identification of 1-O-alkyl glycerol present in the dried leaves of Bauhinia scandens. Fifty percent aqueous ethanolic extract of the plant at room temperature was fractionated over petroleum ether and diethyl ether. The diethyl ether soluble fraction showed positive bioactivity in Brine Shrimp bioassay. Isolation and purification of the active principle was subsequently done from diethyl ether fraction. The diethyl ether fraction was separated into acidic and neutral part. The acid free fraction was screened to be positive in Brine Shrimp bioassay. The NMR spectra (in CDCl3) indicated the probability of its lipoidal nature. The total lipid fraction was resolved into neutral, glyco, and phospho-lipids by column chromatography. Only the neutral fraction sh...
It has by now been established that standard QCD factorization using transverse momentum dependent parton distribution functions fails in hadro-production of nearly back-to-back hadrons with high transverse momentum. The essential problem is that gauge invariant transverse momentum dependent parton distribution functions cannot be defined with process-independent Wilson line operators, thus implying a breakdown of universality. This has led naturally to proposals that a correct approach is to instead use a type of "generalized" transverse momentum dependent factorization in which the basic factorized structure is assumed to remain valid, but with transverse momentum dependent parton distribution functions that contain non-standard, process dependent Wilson line structures. In other words, to recover a factorization formula, it has become common to assume that it is sufficient to simply modify the Wilson lines in the parton correlation functions for each separate ...
Precise measurements of the single spin asymmetry AN, and the double spin asymmetry ANN, in proton-proton (pp) elastic scattering in the region of four-momentum transfer squared 0.0012 have been performed using a polarized atomic hydrogen gas jet target and the Relativistic Heavy Ion Collider (RHIC) polarized proton beam. We present measurements of AN and ANN at center-of-mass energies ?(s)=6.8 and 13.7 GeV. These spin-dependent observables are sensitive to the poorly known hadronic spin-dependent amplitudes. Comparing AN at different energies, a ?(s) dependence of the hadronic single spin-flip amplitude is suggested. A hadronic double spin-flip amplitude from the ANN data is consistent with zero within a 2-? level. We also present ??T, estimated from the measured ANN data. The results for ??T are consistent with zero. Our results provide significant constraints toward a comprehensive understanding of the reaction mechanism ...
We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider, within the supergravity inspired minimal supersymmetric standard model We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider, within the Supergravity inspired Minimal Supersymmetric Standard Model. The phenomenological relevance of such reactions is twofold. Firstly, they constitute a novel production mechanism of Higgs particles, either through a decay of a heavier (anti)squark into a lighter one or via a Higgs bremsstrahlung process. Secondly, their production rates are extremely sensitive to the values assumed by the five input parameters of the model, this possibly allowing one to put stringent constraints on the latter. After an exhaustive scan of the parameter space, we find that the majority of such processes could be detectable at high ...
Complete factorization scheme analysis of $F_2^{\\gamma}(x,Q^2)$ in the next--to--leading order QCD is performed. It is shown that the presence of the inhomogenous term in the evolution equations for parton distribution functions of the photon implies qualitative change in the way factorization mechanism works in photon--hadron and photon--photon collisions as compared to hadron--hadron ones. The incompletness of the existing NLO analyses of $F_2^{\\gamma}(x,Q^2)$ is pointed out and its origins traced back to the misinterpretation of the behaviour of $q^{\\gamma}(x,M)$ as a function of in the LO photonic coefficient function $C_{\\gamma}^{(0)}(x)$ is given and smooth transition between the properties of virtual and real photon discussed. A simple way of avoiding the problems with the term $\\ln(1-x)$ appearing in the standard expression for $C_{\\gamma}^{(0)}(x)$ in the case of the reaal photon is proposed.
In 1996, a field-scale phytoremediation demonstration project was initiated and managed by the U.S. Air Force at a site in western Fort Worth, Texas, using a plantation of 1-year-old stems harvested from branches of eastern cottonwoods during the dormant season (whips) and a plantation of 1-year-old eastern cottonwood seedlings (calipers). The primary objective of the demonstration project was to determine the effectiveness of eastern cottonwoods at reducing the mass of dissolved trichloroethene transported within an alluvial aquifer. The U.S. Geological Survey conducted a study, in cooperation with the U.S. Air Force, to determine water-level variations and their effects on tree growth and mortality and on the biogeochemical system at the phytoremediation site. As part of the study, water-level and water-quality data were collected throughout the duration of the project. This report presents water-level variations at periodic sampling events; data from August ...
There are some indications from recent determinations of the strong coupling constant alpha_s and the gluon condensate that the Operator Product Expansion may not be accurate enough to describe non-perturbative effects in hadronic tau decays. This breakdown of the Operator Product Expansion is usually referred to as being due to"Duality Violations." With the help of a physically motivated model, we investigate these duality violations. Based on this model, we argue how they may introduce a non-negligible systematic error in the current analysis, which employs finite-energy sum rules with pinched weights. In particular, this systematic effect might affect the precision determination of alpha_s from tau decays. With a view to a possible future application to real data, we present an alternative method for determining the OPE coefficients that might help estimating, and possibly even reducing, this systematic error.
This study emphasizes the need for a systematic and in-depth connection between the progress in quantum theory of energetic ion collisions and applications to hadron therapy. Scattering theory for fast ion beams has reached its stage of development where accurate and robustly applicable methodologies can advantageously be exported to applied fields such as space research, fusion energy program, medicine, etc. In particular, distorted wave collision theories at high energies readily provide total, partial and fully differential cross sections for inelastic collisions of ionic projectiles with any target system. By numerous and thorough testings, such theoretical cross sections were found to exhibit excellent agreement with experimental data on atomic targets. Adequate extensions of these me...
The thesis deals with measurement of the mass of the W boson at LEP2, based on the direct reconstruction of its decay products in the hadronic channel. A set of procedures necessary for the extraction of the W mass from the experimental data collected with the DELPHI detector in 1997 was developed (search of optimal variables for the event selection, development of a special method of kinematical reconstruction). The measured value of the mass was interpreted in the framework of the Standard Model, allowing to constrain the mass of the Higgs boson. A substantial part of the work is devoted to systematic effects due to the interactions between the hadronic decay products of the W bosons (colour reconnection and Bose-Einstein correlations), which may significantly influence the measurement of their mass. (author) 53 refs., 104 figs., 33 tabs.
The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.
This contribution deals with identification of fractional-order dynamical systems. System identification, which refers to estimation of process parameters, is a necessity in control theory. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme of estimating the parameters for such a fractional order process is proposed. This method employs fractional calculus theory to find equations relating the parameters that are to be estimated, and then estimates the process parameters after solving the simultaneous equations. The said simultaneous equations are generated and updated using particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. The data used for the calculations are intentionally corrupted to simulate real-life conditions. Results show that the ...
We review the physics of structure functions at low Q{sup 2}, focusing on the phenomenon of quark-hadron duality and the resonance-scaling transition, both phenomenologically and in the context of quark models. We also present a new implementation of target mass corrections to nucleon structure functions which, unlike existing treatments, has the correct kinematic threshold behavior at finite Q{sup 2} in the x -> 1 limit.
We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process {gamma}{gamma}{yields}ZZ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the Z bosons to enhance the signal relative to the background of transversely polarized ZZ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic f{sub 2}(1270) meson. ((orig.)).
We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process {gamma}{gamma} {yields} ZZ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the Z bosons to enhance the signal relative to the background of transversely polarized ZZ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic f{sub 2}(1270) meson.
This document presents our proposal to continue the activities of Boston University researchers in eight projects in high energy physics research: Colliding Beams Physics; Accelerator Design Physics; MACRO Project; Proton Decay Project; Theoretical Particle Physics; Muon G-2 Project; and Hadron Collider Physics. The scope of each of these projects is presented in detail in this paper.
We discuss the origin of Bloom-Gilman duality and the relationship between resonances and scaling in deep-inelastic scattering. We present a simple quantum mechanical model which reproduces the essential features of Bloom-Gilman duality at low Q{sup 2}, and describe applications of local duality relating structure functions at x{approximately}1 and elastic electromagnetic form factors.
Quark models of production of cumulative particles and the EMC effect are analyzed. It is shown that all these models are characterized by a universal relation between the spectrum of cumulative nucleons and the cross section for cumulative particles containing valence quarks of the nucleus. This relation is tested for the deuteron, and the role of secondary nuclear processes for heavy nuclei is discussed. It is noted that the ''sea'' cumulative particles (K"-, p-bar) are particularly important for understanding the nature of the difference between the structure functions of a nucleus and of a free nucleon.
The success of the Randall-Sundrum scenario relies on stabilization of the modulus field or the radion, which is the scalar field about the background geometry. The stabilization mechanism proposed by Goldberger and Wise has the consequence that this radion is lighter than the graviton Kaluza-Klein states so that the first particle to be discovered is the radion. In this work, we study in detail the decay, production, and detection of the radion at hadronic, e{sup +}e{sup -}, and {gamma}{gamma} colliders.
The transition radiation detector (TRD) for the D{Phi} experiment is currently in operation at Fermilab. Transition radiation production, which has been clearly observed in the collider data, makes the TRD a valuable tool to discriminate electrons and hadrons. We describe an algorithm based on the truncated energy, and illustrate its use for top signal and background. (authors). 7 refs., 6 figs., 2 tabs.
The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.
It is shown that account of nuclear effects in nucleon channel is of principle importance when analyzing hadron-nucleon process at high energies. This enables to make correct conclusions both about the contribution of multiquark systems - fluctons - to nuclear wave function and about quark distribution in them. Analysis of these distributions shows that color degrees of freedom in flucton are partially unfrozen and flucton contains with high probability one or two quarks.
The Large Hadron Collider is at the top of world-wide science for particle physics. It promises to open the road to a new knowledge of the universe and its nature. Luciano Maiani and Robert Aymar, actual and future Director Generals of CERN, explain the aims of this most powerful instrument, the difficulties and the industrial repercussions, among which will be the "Grid", that will change the telecommunications (4 pages)
We discuss the main stages of a physical program for photon linear colliders. We consider the problems in electroweak theory, hadron physics, QCD, and nonlinear QED, as well as new particles and interactions, etc. The discussed stages constitute the parts of an entire ambitious program for linear colliders. ((orig.)).
The status of the IEEE 802.3 standard is reviewed and prospects for the future, including the new 10 Gigabit version of Ethernet, are discussed. The relevance of Ethernet for experiments at the CERN Large Hadron Collider is considered, with emphasis on on-line applications and areas which are technically challenging. 8 Refs.
The research of the CELLO collaboration is reviewed. After a description of the CELLO detector tests of QCD and hadronic final states by determination of the strong coupling constant and studies of inclusive production of electrons and muons in multihadronic events in e"+e"- annihilation are described. Then studies of deep inelastic e#gamma# scattering with lepton pair production and the study of the structure function of the photon are briefly described. Finally studies on QED processes are described together with tau decays. (HSI).
If the soft supersymmetry (SUSY) breaking masses and couplings are complex and cancellations do take place in the SUSY induced contributions to the fermionic electric dipole moments, then the CP- violating soft phases can drastically modify much of the known phenomenological pattern of the minimal supersymmetric standard model. In particular, the squark loop content of the dominant Higgs production mechanism at the large hadron collider, the gluon-gluon fusion mode, could be responsible for large corrections to the known cross sections. (15 refs).
Quark models of cumulative particle production and EMS effect are analyzed. All the models are characterized by a universal relationship between the spectrum of cumulative nucleons and the cross section of cumulative particles containing valence nuclear quarks. This relationship is tested for a deuteron. The role is discussed played by secondary nuclear processes for heavy nuclei. A special role of ''sea'' cumulative particles (K"-, p-bar) is pointed out in understanding the nature of the difference between the structure functions of a nucleus and of free nucleon.
The Tevatron collider at Fermilab provides a very rich environment for the study B{sub s} mesons. In this paper they show a few selected topics from the CDF and D0 collaborations, giving special attention to the B{sub s} Mixing analyses. This note corresponds to the proceedings of the Hadron Collider Physics 2005 conference.
The author notes that if hadrons are gravitationally stabilized ``black holes``, as discrete physics suggests, it is possible that partons, and in particular quarks, could be modeled as tachyons, i.e. particles having v{sup 2} > c{sup 2}, without conflict with the observational fact that neither quarks nor tachyons have appeared as ``free particles``. Some consequences of this model are explored.
In this talk I briefly summarize different models for #sigma#_2_#gamma#"t"o"t (e"+e"-#->##gamma##gamma##->#hadrons) and contrast model predictions with the data. I will then discuss the capability of the future e"+e"- and #gamma##gamma# colliders to distinguish between various models and end with an outlook for future work.
In proteomics, one-dimensional (1D) SDS-PAGE is widely used for protein fractionation prior to mass spectrometric analysis to enhance dynamic range of analysis and to improve identification...Full Text Available
A new analysis is presented which links real volume fractions, relaxation rates, and intracompartmental exchange rates directly with apparent volume fractions and relaxation rates obtained from biexponential...Full Text Available
The results of a search for fractionally charged particles produced in e/sup +/e/sup -/ annihilation at 29 GeV/c/sup 2/ are discussed. Results from cosmic-ray searches for fractionally charged particles, tachyons, and massive particles using the same detector are also presented.
The effects of homologous plasma HDL and VHDL fractions on established atherosclerotic lesions were studied in cholesterol-fed rabbits. Atherosclerosis was induced by feeding the animals a 0.5% cholesterol-rich...Full Text Available
The soluble subcellular fraction of a chlB mutant contains an inactive precursor form of the molybdoenzyme nitrate reductase, which can be activated by the addition to the soluble fraction of protein...Full Text Available
Experiments were conducted to determine the dose response of rat bladder urothelium to a range of different single and fractionated intravesicular doses of the carcinogen, N-methyl-N-nitrosourea (MNU)....Full Text Available
The structural properties of brain extracellular space (ECS) are summarised by the tortuosity (λ) and the volume fraction (α). To determine if these two parameters were independent,...Full Text Available
BACKGROUND: Accurate estimation of left ventricular ejection fraction (LVEF) has assumed great significance in the era of automatic implantable cardioverter defibrillators (AICDs), and a low EF may...Full Text Available
The finest particle size fractions ({le} 25 {mu}m) in four fly ash samples from fluidised bed combustion of three biomass based fuels and a municipal solid waste fuel were size separated using a centrifugal SPLITT fractionation cell. The ashes were separated into different size fractions and the cadmium concentration, partition and speciation in each separated fraction were then investigated in relation to their possible leaching. The fractionation was evaluated by environmental scanning electron microscopy, which also provided indications of the associations between Cd and other main elements on the particles through the use of X-ray fluorescence mapping. The total concentration of Cd in each fraction was determined by AAS analysis which showed different dependence on the ash particle size in the case of biomass or waste fuels. In addition, the speciation of Cd ...
When a certain void fraction value is reached in the two-phase flow regime, a problem occurs in the COBRA-EN code. This problem was observed in the drift-flux model option and interrupts code execution. Two solutions are proposed to solve the problem.
Two sediment cores (Southern Branch, PC-1, and Western Branch, WB-2) were taken from the highly industrialized Elizabeth River, Virginia. The concentrations of trace metals cadmium, cobalt, chromium, copper, nickel, lead and zinc, major elements iron, manganese and aluminum, organic carbon content and the specific surface area of the sediments were determined in each of the cores. Down-core variations in metals varied significantly in each core with maximum contamination events occurring at different times in different portions of the river. In PC-1, maximum metal concentrations were seen after the appearance of "1"3"7Cs. In contrast, the highest levels in WB-2 occurred well before the appearance of "1"3"7Cs. Although stricter environmental regulations have caused a decrease in metal concentrations since the 1980s, the concentrations in the surface sediments of many trace metals were elevated to levels 2-5 times higher than the levels at the ...
The K Reactor at the Savannah River Site (SRS) shut-down in spring 1988 for maintenance and safety upgrades. Since that time the receiving stream for thermal effluent, Indian Grave Branch and Pen Branch, have undergone a pattern of post-thermal recovery that is typical of other SRS streams following removal of thermal stress. Divesity of fish and aquatic macroinvertebrate communities has increased and available habitats have been colonized by numerous species of herbaceous and woody plants. K Reactor is scheduled to resume operation in 1991 and operate through 1992 without a cooling tower to cool the discharge. It is likely that the reactor will operate at approximately one-third to one-half of full power (800--1200 MW thermal) during this period and effluent temperatures will be substantially lower than earlier operation at full power. Monthly average discharge temperatures at half-power operation will range from approximately 42 degrees C in ...
Hexane extract of licorice (Glycyrrhiza glabra L.) roots was obtained and investigated. Hydrocarbons, sterol ethers, triacylglycerides, free fatty acids, and free sterols were identified. The extract contains 70% neutral and 30% polar lipids. It is established that the lipid fraction of licorice roots is more effective than the analogous fraction of rosehip oil in stimulating the reparative regeneration of skin. In addition, this fraction also exhibits pronounced antiinflammatory and antiulcer effects, while being virtually nontoxic. Based on these results, the lipid fraction of licorice roots can be recommended as a parent substance for creating effective preparations in various medicinal forms.
System identification is a necessity in control theory. Classical control theory usually considers processes with integer order transfer functions. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme is presented for approximation of such a real world fractional order process by an ideal integral order model. A population of integral order process models is generated and updated by PSO technique, the fitness function being the sum of squared deviations from the set of observations obtained from the actual fractional order process. Results show that the proposed scheme offers a high degree of accuracy.
In this note, we derive from Anstee's fractional $(g,f)$-factor theorem a similar characterization for the property of all fractional $(g,f)$-factors. Let $afractional $[a, b]$-factors if the minimum degree is at least $\\delta(G)\\geq \\frac{1}{4a}((a+b-1)^2+4b)$ and every pair of non-adjacent vertices has cardinality of the neighborhood union at least $bn/(a + b)$. This lower bounds are sharp.
This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
A set of nomographs is presented which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.
Abstract We address the fundamental question of matching the rest-frame K-band luminosity function (LF) of galaxies over the Hubble time using semi-analytic models after modification of the stellar population modelling. We include the Maraston evolutionary synthesis models, which feature a higher contribution by the thermally pulsating asymptotic giant branch (TP-AGB) stellar phase, into three different semi-analytic models, namely the De Lucia and Blaizot version of the Munich model, morgana and the Menci model. We leave all other input physics and parameters unchanged. We find that the modification of the stellar population emission can solve the mismatch between models and the observed rest-frame K-band luminosity from the brightest galaxies derived from UKIRT Infrared Deep Sky Survey d...
Coordination of CoCl2 solutions to the silica polyamine composite, WP-1, made with the branched polymer polyethylenimine (PEI) shows irreversible binding resulting from surface oxidation of the Co2+-Co3+. This is not the case for the silica polyamine composite BP-1 made with the linear polymer polyallylamine where reversible binding and no oxidation is observed. These observations suggested that oxidation of the cobalt was related to the greater coordination number available with the branched polyamine relative to the linear polyamine. A study of the kinetics of cobalt binding to WP-1 indicated initial loading of Co2+ at relatively low coordination number followed by desorption of Co2+ leading to oxidation and irreversible binding. Exclusion of oxygen from the composite-cobalt solution mix...
Determining which kinds of roots are likely to be consumed by root herbivores may improve our understanding of the mechanistic control on fine root dynamics. Here, we tested the hypothesis that root herbivores prefer to consume the distal lower order roots in their branching networks. Insecticide was applied to soil to quantify effects of root herbivores on root biomass and production in the first five orders (the distal roots numbered as first-order) in Fraxinus mandshurica and Larix gmelinii plantations from May 2008 to July 2009. Root morphology, chemistry, anatomy and physiology were measured simultaneously across branching orders. Among the first five order roots, significant consumptions by herbivores were found only for the two distal lower order roots throughout growing seasons, wi...
The unavoidable irreversible losses of power in a heat engine are found to be of quantum origin. Following thermodynamic tradition a model quantum heat engine operating by the Otto cycle is analyzed. The working medium of the model is composed of an ensemble of harmonic oscillators. A link is established between the quantum observables and thermodynamical variables based on the concept of canonical invariance. These quantum variables are sufficient to determine the state of the system and with it all thermodynamical variables. Conditions for optimal work, power and entropy production show that maximum power is a compromise between the quasistatic limit of adiabatic following on the compression and expansion branches and a sudden limit of very short time allocation to these branches. At high temperatures and quasistatic operating conditions the efficiency at maximum power coincides with the endoreversible result. The optimal compression ratio ...
Particle accelerators are constructed and operated for a wide variety of applications. In particle physics - the branch of physics that studies the elementary constituents of matter and forces between them - high energy accelerators are used to look deep into the structure of matter. Medical particle accelerators are used for example in medicine to treat tumours [31], in imaging techniques such as Positron Emission Tomography (PET) [24], or for the radio-isotopes production. They also serve in many other industrial branches, e.g. geology, radiocarbon dating [39], molecular complex spectroscopy, lithography, food preservation etc. The eld of accelerator technology draws knowledge and expertise from a wide range of scientic disciplines and uses the latest technical knowledge. The incomplete list of covered disciplines includes mathematics, physics, electronics, computing, electromagnetic eld technology, microwave technology, cryogenics, vacuum ...
Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab.
Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. (author).
A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.
This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1989, through September 30, 1990. Six technical sections of the report cover these main areas of NREL's in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Solid-State Spectroscopy. Each section of the report was written by the group leader principally in charge of the work. The task in each case was to explain the purpose and major accomplishments of the work in the context of the US Department of Energy's National Photovoltaic Research Program plans.
This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1989, through September 30, 1990. Six technical sections of the report cover these main areas of NREL`s in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Solid-State Spectroscopy. Each section of the report was written by the group leader principally in charge of the work. The task in each case was to explain the purpose and major accomplishments of the work in the context of the US Department of Energy`s National Photovoltaic Research Program plans.
New measuring methods are developed and are tested with the small reactor simulator MIDAS (Mini Dodewaard ASsembly). The purpose of this work is to be able to measure accurately as many different properties of the flow as possible in the coming bigger simulator SIDAS (Simulated Dodewaard ASsembly). In SIDAS the flow around a fuel assembly of the Dutch Dodewaard reactor will be simulated. An extensive evaluation of the gamma detection system showed that the detection system could be simplified strongly. The simplified system is used to measure the radial and axial distribution of the void fraction in the core of MIDAS for three different operating conditions. Two new measuring methods have been developed and tested. A method to estimate the probability density of the void fraction in time. Due to the nonlinear relation between transmission and void fraction the determined average value of the void ...
Radiographic images generated by the real-time neutron radiography system (RTNR) are analyzed by customized image processing software of the determination of instantaneous void fraction distribution. The cross-sectional averaged axial void fraction profiles and the two-dimensional void fraction profiles are determined simultaneously for each image. Various flow regimes are generated to determine if the RTNR system can accurately predict the void distribution in the radial, axial, and temporal coordinates. The results show the RTNR system correctly determines the void fraction distribution for each flow regime; however, accuracy decreases with decreasing void fraction. For net water thicknesses > 1.0 cm, the accuracy decreases with increasing water thickness due to the extreme sensitivity of thermal neutron interactions with light water. Heavy water is a more suitable fluid than ...
A rare, true aneurysm of a branch of the right subclavian artery is described. Transcatheter coil embolization of the feeder artery was successful in obliterating blood flow into the aneurysm and the mass reduced in size. However, the aneurysm reenlarged over the next week of follow-up due to development and enlargement of the collateral vascular network. Extirpation of the aneurysm was performed. Histopathological examination revealed a true aneurysm. PMID:11833847
This report discusses the activities of two major groups of forest soil microorganisms, the bacteria and the fungi. Special attention is paid to their participation in the decay of major forest litter substrates, including leaves, branches and roots. The influence of bacteria and fungi in symbiotic associations with woody plant roots upon the cycles of carbon and nitrogen is described. The impacts of certain forest mamagement alternatives are assessed in terms of the creation of elimination of suitable environments for the activity of soil microorganisms. A bibliography is included. 507 refs., 1 tab.
Although statistical design is one of the oldest branches of statistics, its importance is ever increasing, especially in the face of the data flood that often faces statisticians. It is important to recognize the appropriate design, and to understand how to effectively implement it, being aware that the default settings from a computer package can easily provide an incorrect analysis. The goal of this book is to describe the principles that drive good design, paying attention to both the theoretical background and the problems arising from real experimental situations. Designs are motivated t
Scientists often re-invent things that were long known. Here we review these activities as related to the mechanism of producing power law distributions, originally proposed in 1922 by Yule to explain experimental data on the sizes of biological genera, collected by Willis. We also review the history of re-invention of closely related branching processes, random graphs and coagulation models.
Ozsvath and Szabo show that there is a spectral sequence whose E^2 term is the reduced Khovanov homology of L, and which converges to the Heegaard Floer homology of the (orientation reversed) branched double cover of S^3 along L. We prove that the E^k term of this spectral sequence is an invariant of the link L when k>2. If L is a transverse link, then we show that Plamenevskaya's transverse invariant gives rise to a transverse invariant of L in each of these higher terms.
The lepton flavor-violating coherent ( /sup -/, e/sup -/) conversion is investigated. Photonic and nonphotonic contributions arising in various gauge models are considered. The dependence of the conversion rate on the structure of the nucleus is given by the elastic form factors. These are obtained in the context of shell model taking into account finite-size effects or extracted from the electron scattering data whenever possible. The relevant branching ratios are studied throughout the periodic table.
Standard methods in non-linear analysis are used to show that there exists a parabolic branching of solutions of the Lichnerowicz-York equation with an unscaled source. We also apply these methods to the extended conformal thin sandwich formulation and show that if the linearised system develops a kernel solution for sufficiently large initial data then we obtain parabolic solution curves for the conformal factor, lapse and shift identical to those found numerically by Pfeiffer and York. The implications of these results for constrained evolutions are discussed.
In 2000, a network of twenty-three piezometers was used to measure hydraulic head in the water-table aquifer (Upper Aquifer Zone of the Upper Three Runs Aquifer, or UAZ of the UTRA) along the ground water outcrops (i.e. seeplines) near the F- and H-Areas.
The t<0 branch of pre-big bang cosmological scenarios is subject to a gravitational wave instability. The unstable behaviour of tensor perturbations is derived in a very simple way in Hwang's covariant and gauge-invariant formalism developed for extended theories of gravity. A simple interpretation of this instability as the effect of an ''antifriction'' is given, and it is argued that a universe must eventually enter the expanding phase. (orig.)
Rice, the world's major staple crop, is a poor source of essential micronutrients, including folates (vitamin B9). We report folate biofortification of rice seeds achieved by overexpressing two Arabidopsis thaliana genes of the pterin and para-aminobenzoate branches of the folate biosynthetic pathway from a single locus. We obtained a maximal enhancement as high as 100 times above wild type, with 100 g of polished raw grains containing up to four times the adult daily folate requirement.
EREC, the international umbrella organization, published last year a study on export strategies for renewable energy technologies. The 150-page document provides valuable information on key export markets and financial institutions, and presents the various branches' perspectives for the future. The following excerpts will whet your appetite for more. The complete study is available for download: www.erec-renewables.org (Eurees). (orig.)
This environmental review of right-of-way clearing for transmission projects has been undertaken by the Environmental Analysis Branch for the Division of Land Resources in BPA's Office of Engineering and Construction. It is intended to review the present practices and results of selective clearing, and to make recommendations toward improvements in environmental practices and procedures in mitigation development for impacts associated with right-of-way clearing. 29 figs.
Short review of works on astatine chemistry carried out by authors for the last thirty years are done. Discovery of single-charged cation stable in aqueous solutions is predominant attainment of authors in the branch of inorganic chemistry. The first successful synthesis of heptavalent astatine compounds is a new and significant result of the last years. New direction in the chemistry of the fifth halogen is organic chemistry of astatine
Indicators of source water use in different economic branches, water consumption in recycling and recycling-successive water supply in 1980?2006 are analyzed. Trends were identified in variations in specific water consumption in industry, agriculture, and municipal economy. Territorial differentiation of wetness indicators of regional product over federal districts and constituent territories of the RF is shown. Wetness values of gross domestic product in different economies are compared.
EPA's Brownfields Economic Redevelopment Initiative was established to assist states, site planners and other community stakeholders to work together to assess, cleanup and sustainably reuse brownfields sites. EPA has developed a series of guides to help these parties effectively...
Nuclear forensics is a relatively new scientific branch whose aim it is to read out material inherent information from nuclear material. On the basis of material taken in safe-keeping in Germany, the procedure is illustrated and the limits and possibilities of nuclear forensics are shown, in particular the statements that can be made concerning the material, and the relation of the material with respect to a certain location of origin or manufacturing process. (orig.)
We give a closed formula for volumes of generic hyperbolic tetrahedra in terms of edge lengths. The cue of our formula is by the volume conjecture for the Turaev-Viro invariant of closed 3-manifolds, which is defined from the quantum 6j-symbols. This formula contains the dilogarithm functions, and we specify the adequate branch to get the actual value of the volumes.
We study a variant of the Penner-Distler-Vafa model, proposed as a c = 1 quantum gravity: quenched' matrix model with logarithmic potential. The model is exactly soluble, and exhibits a two-cut branching as observed in multicritical unitary matrix models and multicut Hermitian matrix models. Using analytic continuation of the power in the conventional polynomial potential, we also show that both the Penner-Distler-Vafa model and our quenched' matrix model satisfy Virasoro algebra constraints.
The Large Hadron Collider presents an unprecedented opportunity to probe the realm of new physics in the TeV region and shed light on some of the core unresolved issues of particle physics. These include the nature of electroweak symmetry breaking, the origin of mass, the possible constituent of cold dark matter, new sources of CP violation needed to explain the baryon excess in the universe, the possible existence of extra gauge groups and extra matter, and importantly the path Nature chooses to resolve the hierarchy problem - is it supersymmetry or extra dimensions. Many models of new physics beyond the standard model contain a hidden sector which can be probed at the LHC. Additionally, the LHC will be a top factory and accurate measurements of the properties of the top and its rare decays will provide a window to new physics. Further, the LHC could shed light on the origin of neutralino masses if the new physics associated with their generation lies in the TeV ...
We present the complete next-to-leading order (NLO) QCD corrections to the top quark associated with $\\gamma$ production induced by model-independent $tq\\gamma$ and $tqg$ flavor-changing neutral-current (FCNC) couplings at hadron colliders, respectively. We also consider the mixing effects between the $tq\\gamma$ and $tqg$ FCNC couplings for this process. Our results show that, for the $tq\\gamma$ couplings, the NLO QCD corrections can enhance the total cross sections by about 50% and 40% at the Tevatron and LHC, respectively. Including the contributions from the $tq\\gamma$, $tqg$ FCNC couplings and their mixing effects, the NLO QCD corrections can enhance the total cross sections by about 50% for the $tu\\gamma$ and $tug$ FCNC couplings, and by about the 80% for the $tc\\gamma$ and $tcg$ FCNC couplings at the LHC, respectively. Moreover, the NLO corrections reduce the dependence of the total cross section on the renormalization and factorization scale ...
The presented results are the first measurements at RHIC for direct $\\gamma$-charged hadron azimuthal correlations in heavy ion collisions. We use these correlations to study the color charge density of the medium through the medium-induced modification of high-p$_T$ parton fragmentation. Azimuthal correlations of direct photons at high transverse energy (8 $<$ p$_T$ $<$ 16 GeV) with away-side charged hadrons of transverse momentum (3 $<$ p$_T$ $<$ 6 GeV/c) have been measured over a broad range of centrality for $Au+Au$ collisions and $p+p$ collisions at $\\sqrt{s_{NN}}$ = 200 GeV in the STAR experiment. A transverse shower shape analysis in the STAR Barrel Electromagnetic Calorimeter Shower Maximum Detector is used to discriminate between the direct photons and photons from the decays of high p$_T$ $\\pi^{0}$. The per-trigger away-side yield of direct $\\gamma$ is smaller than from $\\pi^{0}$ trigger at the same centrality class. ...
We discuss the impact for light neutralinos in an effective Minimal Supersymmetric extension of the Standard Model of the recent results presented by the CMS and ATLAS Collaborations at the CERN Large Hadron Collider for a search of supersymmetry in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 35 inverse pb. We find that, in the specific case of light neutralinos, efficiencies for the specific signature searched by ATLAS (jets+missing transverse energy and an isolated lepton) imply a lower sensitivity compared to CMS (which searches for jets +missing transverse energy). Focusing on the CMS bound, if squark soft masses of the three families are assumed to be degenerate, the combination of the ensuing constraint on squark and gluino masses with the experimental limit on the b to s + gamma decay imply a lower bound on the neutralino mass that can reach the value of 11.9 GeV, depending on the gluino mass. On the other ...
CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an industrial development ...
A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving aside exotic spectroscopy, which has been the subject of other publications, in this note I call attention on two recent applications. One is that the running quark mass in the mid-infrared can be probed from excited baryons thanks to parity doubling, a consequence of insensitivity to chiral symmetry breaking. Fast quarks are asymptotically free and behave as massless, so hadrons containing fast quarks decouple from the condensate. Their (power-law) rate of decoupling reflects on the rate of decreasing parity splittings, which can be measured. The second is that, in analogy with the Franck-Condon principle of molecular physics, the velocity distribution of the heavy quarks inside a heavy hadron can be mapped out ...
The Alice experiment is one of the four main LHC (Large Hadron Collider) experiments. It is dedicated to the study of a new state of matter: the quark gluon plasma, where quarks and gluons are no longer confined within hadrons. In this document, the physics issues that led to the construction of Alice dimuon spectrometer, are described. Then, the research and development on the dimuon spectrometer is presented. The different absorbers are described and experimental tests used to determine their dimensions are presented. The dimuon trigger built using the RPC (Resistive Plate Chamber) streamer mode is then described along with the associated beam and cosmic tests and results. Finally, the tracking system is described in detail and more particularly all its electronics and the first station. The physics constraints on the expected performances of all these systems are clearly defined. (author)
Complete calculations of the accelerator related background in the muon spectrometer of the CMS detector at the Large Hadron Collider are presented. The simulations have been performed with the STRUCT multi-turn tracking code and the MARS and FLUKA cascade codes taking into account latest information of the LHC lattice, vacuum conditions, beam cleaning system and the shielding and layout of the CMS experiment. Beam loss distributions in the interaction regions and their vicinities and their contribution to the background levels in the muon spectrometer of CMS are analyzed. The studies show that hadronic and electromagnetic components of machine background are efficiently suppressed by the proposed CMS shielding. High energy muons penetrate through the shielding, but in positions of significance they do not contribute more than a few percent compared to the background generated by the pp-collisions. It is anticipated that the relative ...
The Drell-Yan mechanism for the production of lepton pairs is one of the most basic processes for physics studies at hadron colliders. It is therefore important to have accurate theoretical predictions. In this work we compute the two-loop virtual mixed QCD x QED corrections to Drell-Yan production. We evaluate the Feynman diagrams by decomposing the amplitudes into a set of known master integrals and their coefficients, which allows us to derive an analytical result. We also perform a detailed study of the ultraviolet and infrared structure of the two-loop amplitude and the corresponding poles in epsilon.
Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting the joint project integrating both the Neutron Science Project (NSP) of JAERI and the Japan Hadron Facility Project (JHF) of KEK for comprehensive studies on basic science and technology using high-intensity proton accelerator. This document describes the joint project prepared by the Joint Project Team of JAERI and KEK to construct accelerators and research facilities necessary both for the NSP and the JHF at the site of JAERI Tokai Establishment. It was originally written in English and translated into Japanese with some corrections. (author)
The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).
Supersymmetry, a new symmetry that relates bosons and fermions in particle physics, still escapes observation. Search for SUSY is one of the main aims of the recently launched Large Hadron Collider. The other possible manifestation of SUSY is the Dark Matter in the Universe. The present lectures contain a brief introduction to supersymmetry in particle physics. The main notions of supersymmetry are introduced. The supersymmetric extension of the Standard Model - the Minimal Supersymmetric Standard Model - is considered in more detail. Phenomenological features of the MSSM as well as possible experimental signatures of SUSY at the LHC are described. The DM problem and its possible SUSY solution is presented.
Thomas Jefferson National Accelerator Facility experiment E01-012 measured the 3He spin structure functions and virtual photon asymmetries in the resonance region in the momentum transfer range 1.0 < Q2 < 4.0 (GeV/c)2. Our date, when compared with existing deep inelastic scattering data, can be used to test quark-hadron duality in g1 and A1 for 3He and the neutron. Preliminary results for A{sub 1}{sup {sup 3}He} are presented, as well as some details about the experiment.
An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.
We consider the impact of a 4th generation on Higgs to $\\gamma\\gamma$ and $WW,ZZ$ signals and demonstrate that the Tevatron and LHC have essentially eliminated the possibility of a 4th generation if the Higgs is SM-like and has mass below 200 GeV. We also show that the absence of enhanced Higgs signals in current data sets in the $\\gamma\\gamma$ and $WW,ZZ$ final states can strongly constrain (almost eliminate) the possibility of a 4th generation in two-Higgs-doublet models of type II (in the MSSM).
The Large Hadron Collider (LHC) project, approved by the CERN Council in December 1994, has now fully entered its construction phase, with the detailed technical definition of the major systems, and the adjudication of a number of large procurement contracts. We first recall the main features and characteristics of the LHC, report on the advances in definition of the layout and optics as well as on preparation of the injector complex, and review recent progress in the key technical systems of the main ring: magnets, cryogenics and vacuum, as well as civil construction, which has started following acceptance by authorities in the Host States.
#pi#"#+-# and K"#+-# cumulative production in pA #-># #pi#"#+-#+x and pA #-># K"#+-#+x reactions at 10.14 GeV proton beam energy on nuclei (Be-Ta) was invesigated. Measurements were conducted using FAS-1 focusing hadron spectrometer. Invariant cross sections of #pi#"#+-# and K"#+-# cumulative production, values of ratio of this cross sections, dependences of production cross sections for pions and kaons on cumulative number and mass number of nucleus target, as well as on transverse momentum are measured. Difference of cumulative meson spectra occurring in different nuclei fragmentation is discussed in terms of flucton model. 17 refs.; 14 figs.
Quark models of production of cumulative particles and the EMC effect are analyzed. It is shown that all these models are characterized by a universal relation between the spectrum of cumulative nucleons and the cross section for cumulative particles containing valence quarks of the nucleus. This relation is tested for the deuteron, and the role of secondary nuclear processes for heavy nuclei is discussed. It is noted that the ''sea'' cumulative particles (K/sup -/, p-bar) are particularly important for understanding the nature of the difference between the structure functions of a nucleus and of a free nucleon.
We analyse data on forward {eta} -meson photoproduction off a proton target and extract the {eta}{yields}{gamma}{gamma} decay width utilizing the Primakoff effect. The hadronic amplitude that enters into our analysis is strongly constrained because it is fixed from a global fit to available {gamma}p{yields}p{eta} data for differential cross-sections and polarizations. We compare our results with present information on the two-photon {eta} -decay from the literature. We provide predictions for future PrimEx experiments at Jefferson Laboratory in order to motivate further studies. (orig.)
We consider propagation of relativistic heavy nuclei injected by a young pulsar into the radiation field of a massive companion. If the binary system (BS) is compact enough, then the nuclei suffer multiple photodisintegrations in collisions with thermal photons coming from the massive star (MS). Due to the propagation effects of charged particles in the magnetic field of the MS some hadrons can impinge onto the MS surface at large angles. We calculate the fluxes of produced neutrinos as a function of the viewing angle measured from the plane of the BS. It is found that significant fluxes of neutrinos should be also expected in the case of non-eclipsing BSs.
First measurements of inclusive Z production cross sections in muon and electron decay channels at 7 TeV are presented for proton-proton collisions in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The comparison of the kinematic quantities as well as the studies of selection efficiencies demonstrate a good agreement between simulated events and current data. The measured inclusive cross section for Z($\\gamma^{*}$) production agrees with NNLO QCD cross section calculations and current parton distribution functions.
The mass of the nucleon is studied in a chiral quark-diquark model. Both scalar and axial-vector diquarks are taken into account for the construction of the nucleon state. After the hadronization procedure is used to obtain an effective meson-baryon Lagrangian, the quark-diquark self-energy is calculated to generate the baryon kinetic term as well as determine the mass of the nucleon. It turns out that both the scalar and axial-vector parts of the self-energy are attractive for the mass of the nucleon. We investigate the range of parameters that can reproduce the mass of the nucleon.
multi-parton interactions and underlying event structure, $\\gamma$-mediated processes and luminosity determination, Monte Carlo tuning and even MSSM Higgs discovery in central exclusive production. In this article, the forward detector instrumentation around the CMS interaction point is described and the prospects for diffractive and forward physics using the CMS forward detectors are summarized. In addition, first observation of forward jets as well as early measurements of the forward energy flow in the pseudorapidity range $3.15
The Compact Muon Solenoid (CMS) is one of the experiments which are being designed in the framework of the Large Hadron Collider (LHC) project at CERN. The design field of the CMS magnet is 4 T, the magnetic length is 12.38 m and the aperture is 6.36 m. This is achieved with a 4 layer-5 module superconducting Al-stabilized coil energised at a nominal current of 20 kA. The finite element analysis (FEA) carried out is axisymmetric elasto-plastic. FEA has also been carried out on the suspension system and on the conductor. (8 refs).
The homogeneity of the magnetic field in the LHC dipoles strongly depends on the correct position of the superconducting cables: this is related to the quality of the dipole components, such as the dimension of the coil spacers (copper wedges), of the cable and of the collars. The performance in operational conditions is also affected by the magnetization of the cables. In this work, we analyse the measurements of these quantities during the production of the 1276 LHC dipoles, their trends, and the relation to the measured magnetic field. A novel mtehod to locate electrical shorts based on the analysis of magnetic measurements is also presented, and applications to 15 dipoles reascued during the production is given.
Using the finite-range regularisation (FRR) of chiral effective field theory, the chiral extrapolation formula for the vector meson mass is derived for the case of partially-quenched QCD. We re-analyse the dynamical fermion QCD data for the vector meson mass from the CP-PACS collaboration. A global fit, including finite lattice spacing effects, of all 16 of their ensembles is performed. We study the FRR method together with a naive polynomial approach and find excellent agreement ~1% with the experimental value of M_rho from the former approach. These results are extended to the case of the nucleon mass.
The geodesic equation for space-like objects moving along a circular trajectory in the expanding universe is considered. Our analysis leads to the conclusion that ancient cosmological tachyons may exist in the present-day world and may play an important role in (i) the internal structure of hadrons conceived as nonlocal objects called strings, (ii) the T-symmetry violation observed in the weak K-decays, (iii) the multidimensional unified field theories of Kaluza-Klein type, and in (iv) the classical models of charged particles which combine ordinary electromagnetism with a self-interacting version of Newtonian gravity. 18 refs.
The geodesic equation for space-like objects moving along a circular trajectory in the expanding universe is considered. Our analysis leads to the conclusion that ancient cosmological tachyons may exist in the present-day world and may play an important role in (i) the internal structure of hadrons conceived as nonlocal objects called strings, (ii) the T-symmetry violation observed in the weak K-decays, (iii) the multidimensional unified field theories of Kaluza-Klein type, and in (iv) the classical models of charged particles which combine ordinary electromagnetism with a self-interacting version of Newtonian gravity. 18 refs.
We discuss the recent excess seen by the CDF Collaboration in the dijet invariant mass distribution produced in association with a $W$ boson. We analyze the possibility of such a signal within the context of a $U(1)_X$ Stueckelberg extension of the Standard Model where the new gauge boson couples only to quarks. In addition to the analysis of the $Wjj$ anomaly we also discuss the production of $Zjj$ and $\\gamma jj$ at the Tevatron. The analysis is then extended to the Large Hadron Collider with $\\sqrt{s}=7 {\\rm TeV}$ and predictions for the dijet signals are made.
Full text.Sediments are the ultimate sink of trace elements. The total metal analysis may only give information concerning possible enrichment of metals. The analysis of metal partitioning in the different chemical components of sediments (exchangeable, carbonate, easily reducible, moderately reducible, organic and residual); give a detailed information on the way in which these metals are bound to sediments, their mobilization capacity and their ability to affect water quality under different environmental conditions. The studied river basin is dominated by limestone formation, the enrichment of metals in the carbonate sediment fraction is a high probability. The objective of the study was to determine the percentage of the total metal content (Fe, Mn, Zn, Cu and Pb) in the six chemical fractions of the bed load sediments of Nahr-Ibrahim river during the dry season and verify the role of carbonate for metal sediment deposition. Bed load ...
In radiation therapy with hadron beams, conformal irradiation to a tumour can be achieved by using the properties of incident ions such as the high dose concentration around the Bragg peak. For the effective utilization of such properties, it is necessary to evaluate the volume irradiated with hadron beams and the deposited dose distribution in a patient's body. Several methods have been proposed for this purpose, one of which uses the positron emitters generated through fragmentation reactions between incident ions and target nuclei. In the previous paper, we showed that the maximum likelihood estimation (MLE) method could be applicable to the estimation of beam end-point from the measured positron emitting activity distribution for mono-energetic beam irradiations. In a practical treatment, a spread-out Bragg peak (SOBP) beam is used to achieve a uniform biological dose distribution in the whole target volume. Therefore, in the ...
In this paper we discuss possible signatures for the production of scalar t_1t_1"* (top squarkonium) bound states #sigma#_t_1 at hadron colliders, where t_1 is the lighter scalar top eigenstate. We first study the decay of #sigma#_t_1; explicit expressions are given for all potentially important decay modes. If t_1 has unsuppressed two-body decays, they will always overwhelm the annihilation decays of #sigma#_t_1. Among the latter, we find that usually either the gg or hh final state dominates, depending on the size of the off-diagonal entry of the top squark mass matrix; h is the lighter neutral scalar Higgs boson of the minimal supersymmetric model. If m_#sigma#_t happens to be close to the mass of one of the neutral scalar Higgs bosons, Q bar Q final states dominate (Q=b or t). W"+W"- and ZZ final states are subdominant. We argue that #sigma#_t_1#->##gamma##gamma# decays offer the best signal for top squarkonium production at hadron ...
A state of the art review of two-phase void fraction models in smooth horizontal tubes is provided and a probabilistic two-phase flow regime map void fraction model is developed for refrigerants under condensation, adiabatic, and evaporation conditions in smooth, horizontal tubes. Time fraction information from a generalized probabilistic two-phase flow map is used to provide a physically based weighting of void fraction models for different flow regimes. The present model and void fraction models in the literature are compared to data from multiple sources including R11, R12, R134a, R22, R410A refrigerants, 4.26-9.58 mm diameter tubes, mass fluxes from 70 to 900 kg/m{sup 2} s, and a full quality range. The present model has a mean absolute deviation of 3.5% when compared to the collected database. (author)
We compared the values of the myocardial thickness and the left ventricle diameters measured with MRI and echocardiography. The ejection fraction was compared in MRI and ventriculography. 34 patients with different heart dysfunctions were examined with MRI (FISP 2D sequence). 26 of them were also studied by echocardiography and 20 by biplane cine-ventriculography. The enddiastolic thicknesses of the left ventricular postero-lateral wall and of the septum interventriculare were measured on short axis images. An ellipsoidal modell was used for volume calculation and ejection fraction. Correlation of MRI values of thickness and ejection fraction with echocardiographi and angiographi showed r>0,8. As known for 1.56 T Imagers, the myocardial thickness in MRI was underestimated compared to echocardiography (1.4 mm#+-#1.7). The ejection fraction was underevaluated compared to ventriculography ...
Maytenus ilicifolia Mart. ex Reissek is traditionally used in Brazil for treatment of gastric ulcers. Here we report the phytochemical investigation of an ethanol extract of M. ilicifolia leaves (EEMIL) aiming at the isolation of constituents which were used as chemical markers to monitor an activity-guided fractionation of a lyophilized aqueous extract of M. ilicifolia leaves (LAEMIL). From EEMIL, four flavonoids were isolated, namely the tri-flavonoid glycosides mauritianin (1), trifolin, (2) hyperin (4), and epi-catechin (5). Fractionation of LAEMIL led to 5 fractions which afforded the tetra-glycoside kaempferol derivative (3), and galactitol (6). LAEMIL and its fractions were evaluated in rats for their effects on gastric secretion volume and pH. HPLC (High Performance Liquid Chromatography) analysis revealed that only fractions containing the tri- and tetra-flavonoid ...
Tar sand bitumen is petroleum-based ultra-heavy oil, and has a great amount of reserve like coal. However, there are still a lot of problems for its highly effective utilization. This paper discusses whether the light components in bitumen show independent behavior during the thermal cracking of heavy components, or not. Solvent effect and reaction mechanism during the thermal cracking are also derived from the change of their chemical structures. Athabasca tar sand bitumen was separated into light and heavy fractions by vacuum distillation based on D-1660 of ASTM. Mixtures of the both fractions at various ratios were used as samples. Negative effect of the light fraction on cracking of the heavy fraction was observed with dealkylation and paraffin formation Polymerization of the dealkylated light fraction to the heavy fraction was suggested due to lack of ...
The refrigerant two-phase flows in a distributor and a simulated plate heat exchanger with a single passage used in a compression-type refrigerator were visualized by real-time neutron radiography. For a distributor, the liquid fraction in the each tube was measured by some image processing method. On the other hand, for a plate heat exchanger, the two-dimensional distribution of void fraction was measured quantitatively by the umbra method. As a result, it was shown that the dynamic behaviors of refrigerant at the inlet of the section strongly affected on the performance, that is, a distribution performance of a distributor and a liquid distribution in a plate heat exchanger. (author)
A few industry-derived and conventional building materials have above acceptable radioactivity. An examination of some materials presently used, or with a potential for use, has shown that in phosphogypsum, fly ash, zircon kyanite tailings, red mud and brickmaking clay, the radium equivalent activities of the finer fractions (<53 #mu#) are higher than those of the larger fractions. Consequently, the radioactivity of these materials could be reduced by dry-sieving and discarding the fines. In blast furnace slag and dissociated zircon, no such reduction would occur since the radioactivity is evenly distributed in all sized fractions.
Particle Swarm Optimization technique offers optimal or suboptimal solution to multidimensional rough objective functions. In this paper, this optimization technique is used for designing fractional order PID controllers that give better performance than their integer order counterparts. Controller synthesis is based on required peak overshoot and rise time specifications. The characteristic equation is minimized to obtain an optimum set of controller parameters. Results show that this design method can effectively tune the parameters of the fractional order controller.
A real-time two-dimensional void fraction distribution measurement of gas-liquid two-phase flow was carried out by real-time neutron radiography and real-time image processing. The JRR-3M real-time thermal neutron radiography system and a Musashi dynamic image processing system were used. Image processing methods to calculate two-dimensional and cross-sectional void fraction distributions were proposed. The void fraction distribution was calculated by non-linear processing of the neutron radiography image and displayed by pseudo-color in real-time. A simple gas-liquid two-phase flow induced by injecting gas through needles at the bottom of water pool in a rectangular vessel was tested. (orig.).
The Proportional-Integral-Derivative Controller is widely used in industries for process control applications. Fractional-order PID controllers are known to outperform their integer-order counterparts. In this paper, we propose a new technique of fractional-order PID controller synthesis based on peak overshoot and rise-time specifications. Our approach is to construct an objective function, the optimization of which yields a possible solution to the design problem. This objective function is optimized using two popular bio-inspired stochastic search algorithms, namely Particle Swarm Optimization and Differential Evolution. With the help of a suitable example, the superiority of the designed fractional-order PID controller to an integer-order PID controller is affirmed and a comparative study of the efficacy of the two above algorithms in solving the optimization problem is also presented.
The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...
Pore Fraction in Yttrium-Barium-Copper-Oxide and. Other Polycrystalline. Materials ...... Properties of Yttrium Ceramic. Sov. J. LowTemp.Phys. 14:395-402 . ...
A high pressure piezometer is described with which pVT-measurements on solutions of gases in liquids like oils can be performed at pressures and temperatures up to 2000 bar and 440 K, respectively. The present investigations deal mainly with the system squalaneCO/sub 2/ at different mole fractions, but also with squalaneN/sub 2/. The high accuracy of the measurements reveals a pronounced structure of the pV-curves in dependence on temperature and mole fraction. At larger mole fractions is the unequivocal assignment of the phases ambiguous, and the representation of the experimental data in terms of an equation of state not possible for the whole pressure and temperature range. However, for solutions with lower mole fractions could be determined the saturation pressures and the isothermal compressibility in the unsaturated region. Furthermore, the molar excess volumes of the mixture have been calculated ...
A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale ...
We study dipolar bosons in a 1D optical lattice and identify a region in parameter space---strong coupling but relatively weak on-site repulsion---hosting a series of stable CDW states whose low-energy excitations, built from "fractional domain walls", are remarkably similar to those of non-abelian fractional quantum Hall states. Here, a conventional domain wall between translated CDW's may split by inserting strings of degenerate, but inequivalent, CDW states. Outside these insulating regions, we find numerous supersolids as well as a superfluid regime. The mentioned phases should be accessible experimentally, and in particular, the fractional domain walls can be created in the ground state using single-site addressing, i.e. by locally changing the chemical potential.
PurposeTo determine the dosimetric impact of inter-fraction anatomical movements in prostate cancer patients receiving proton therapy.Full Text Available
Diffusion in the extracellular space (ECS) of the brain is constrained by the volume fraction and the tortuosity and a modified diffusion equation represents the transport behavior of many molecules...Full Text Available
Background:To determine nutrient requirements by the carbon oxidation techniques, it is necessary to know the fraction of carbon dioxide produced during the oxidative...Full Text Available
Determination of the radiocarbon (14C) content of airborne particulate matter yields insight into the proportion of the carbonaceous material derived from fossil and contemporary carbon sources. Daily samples of PM2.5 were collected by high-volume sampler at an urban background site in Birmingham, UK, and the fraction of 14C in both the total carbon, and in the organic and elemental carbon fractions, determined by two-stage combustion to CO2, graphitisation and quantification by accelerator mass spectrometry. OC and EC content was also determined by Sunset Analyzer. The mean fraction contemporary TC in the PM2.5 samples was 0.50 (range 0.27-0.66, n=26). There was no seasonality to the data, but there was a positive trend between fraction contemporary TC and magnitude of SOC/TC ratio and fo...
The concentration of apolipoproteins was measured by quantitative immunoelectrophoresis in rat serum, in the lipoprotein-free ultracentrifugal fraction (density greater than 1.21) of serum, and in renal...Full Text Available
The challenges of lung cancer radiotherapy are intra/inter-fraction tumor/organ anatomy/motion changes and the need to spare surrounding critical structures. Evolving radiotherapy technologies, such...Full Text Available
The forest products industry is the third largest economic sector in Alberta, producing pulp and paper, dimensional lumber, paneling, and value added products, providing some 40,000 jobs . 'Value added' is a key component of expanding economic activity within the forest products sector. Wood residues can play a key role in obtaining more value from forest resources by providing new products, serving as feedstock to energy and chemical production, and playing a role in agriculture and land reclamation. One of the principal roles of the Forest Products Development Branch of the Alberta Economics Department is to encourage the development of the industry by creating new uses for these materials and developing awareness of the scope of the resource. Distances to markets, economic competition from conventional energy sources and coordination of research efforts are substantial barriers to further development that the Forest Products Development ...
Purpose: The present research aims to identify the difficulties and obstacles for developing digital libraries in the seven regional branches of Islamic Azad University (IAU), Iran, and to study the status of librarians' skills and education programmes at these institutions. Design/methodology/approach: The 40 individuals working in the regional branch libraries of IAU were surveyed by a questionnaire consisting of 34 questions, and the collected data were analysed using SPSS software (version 16). Findings: It was found that the most important difficulties are the lack of suitable equipment and untrained personnel (i.e. a lack of sufficient training programmes). Research limitations/implications: Because of the small number of participants, it is suggested that a larger scale study is carried out. It is also proposed that the suggestions made by the participants will be considered and implemented, based on the digital library (DL) developments ...
Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, an improved version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multicomponent gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines (3-50 atm, 650-1200K, stoichiometric fuel/air ...
We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alpha alpha_s^n ln^n m_b/M_W) corrections and improves on our previous analysis of electroweak effects in B -> X_s gamma. We describe in detail several interesting technical aspects of the calculation and include all dominant QED matrix elements. In our final result, we neglect only terms originated from the unknown O(alpha alpha_s) evolution of the Wilson coefficients and some suppressed two-loop matrix elements. Due to the compensation among different effects, we find that non-trivial electroweak corrections decrease the branching ratio by about 3.8% for a light Higgs boson, in agreement with our previous analysis. As in [1], the corresponding SM prediction for the branching ratio with E_gamma > 1.6 GeV is (3.60 +- 0.30) x 10^-4.
A study of two forest areas in India investigated how much energy is wasted when high stumps are left after trees are cut to produce wooden boxes for packing the apple harvest. Measurements of the stumps determined the total wood pulp wasted, which was 1191 tons during 1981. The calorific value of the stumps would supply a year's cooking and heating fuels for 747 families of five. Additional fuel is wasted by abandoning the branches and tree tops which are unsuitable for box construction. 5 references, 4 tables.
In symmetrical nuclear matter the solutions of pion dispersion equation are investigated in the complex plane of the pion frequency $\\omega$. There are three well-known branches of solutions on the physical sheet : sound, pion and isobar, at the matter density less than the critical one $\\rho <\\rho_c$. At the condition $\\omega^2_c\\leq0$ (in general case Re$ \\omega^2_c\\leq0$) takes place. This points out the instability of the ground state which is possibly related to the pion condensation.
After presenting a general account of the observed global properties of single stars of low, intermediate, and high mass, together with their theoretical Hertzsprung-Russell diagram evolution, attention is given to the observed properties of various evolved close binaries and to an assessment of the value of comparisons between observation and crude theory in characterizing the physics of mass transfer within interacting binary systems. Detailed consideration is then undertaken of such topics as stellar evolution in globular clusters, interior star changes due to nucleosynthesis and mixing, asymptotic giant branch stars of intermediate mass, the response of white dwarfs in binary systems to mass accretion, and scenarios for binary star evolution tending toward close white dwarf pairs.
The CP violating processes J/psi-->K_S K_S and psi(2S)-->K_S K_S are searched for using samples of 58 million J/psi and 14 million psi(2S) events collected with the Beijing Spectrometer at the Beijing Electron Positron Collider. No signal is observed, and upper limits on the decay branching ratios are determined to be BR(J/psi-->K_S K_S) K_S K_S) < 4.6x10^{-6} at the 95% confidence level.
Polytetrafluoroethylene was obtained by radiation induced polymerization of tetrafluoroethylene in acetone at 195 K. An average diameter of the products was very small compared with commercial one; it was about 0.3 micro-meters. The yield was reached to 100% with a dose of 4 kGy. The crystallinity of the products is decreasing with increasing dose. The products become amorphous, for higher irradiation doses. It was found that PTFE obtained by irradiation of TFE in acetone at 195 K has branching structure. This was demonstrated by means of "1"9F MAS NMR. (Author)
The paper presents a comprehensive analysis of the energy conservation policy conducted in the Central and Eastern European countries - its development from the start of reforms and up to the present. The problems of rational energy consumption are shown to be closely connected with the concrete conditions of the transition from the economy based on the command principles to the market economy. The author indicates the main areas of application for energy conservation activities. He also describes the models for determination of energy intensity in different branches of energy economy, and organisational structure of the measures to be taken foe energy conservation. (author)
Scientists of the Institute of Wood Chemistry of the Latvian Academy of Sciences have developed two highly efficient processes for producing furfural, a feedstock for varnishes, synthetic resins and plastics. It is made of production wastes, including branches and small-dimension timber. By one process, the raw material is chipped, treated first with diluted sulphuric acid and then with steam heated to 250 degrees C. The other uses concentrated sulphuric acid as a catalyst. Besides furfural, this process also yields sugar solutions used in alcohol and nutrient yeast production.
The results of studies of the time-resolved luminescence of self-trapped excitons (STE) with different multiplicity as well as the X-ray emission in oriented BeO crystals under excitation in the vicinity of the 1 s Be photoabsorption edge are presented. The branching of the electronic excitations relaxation depends strongly on the crystal orientation after the inner-shell excitation. The common features between the processes of the STE luminescence and resonantly excited X-ray fluorescence have been discussed.
By the methods of small-angle X-ray scattering and translucent electron microscopy the existence of inhomogeneity of electron density in hydrogenated films of amorphous silicon is confirmed. The decreased density regions are extended and form a branched network of channels oriented mostly by the normal direction to the films surface. The typical size of the decreased density regions network constitutes 10 nm in the 100-800 nm films thickness range. The increase of hydrogen total partial pressure in gas mixture in case of films growth results at first in the decrease of extension of these regions and than to micropores generation in the network nodal points of the decreased electron density regions.
Information security involves many branches of effort, including information assurance, host level security, physical security, and network security. Computer network security methods and implementations are given a top-down description to permit a medically focused audience to anchor this information to their daily practice. The depth of detail of network functionality and security measures, like that of the study of human anatomy, can be highly involved. Presented at the level of major gross anatomical systems, this paper will focus on network backbone implementation and perimeter defenses, then diagnostic tools, and finally the user practices (the human element). Physical security measures, though significant, have been defined as beyond the scope of this presentation.
The failure took place on a welded elbow pipe which exhibited a catastrophic transverse rupture. The failure was located on the welding HAZ region, parallel to the welding path. Branching cracks were detected at the edge of the rupture area. Deposits of corrosion products were also spotted. The optical microscope analysis showed the presence of transgranular failures which were related to the stress corrosion cracking (SCC) and were predominantly caused by the welding residual stress. The significant difference in hardness between the welded area and the pipe confirmed the findings. Moreover, the failure was also caused by the low Mo content in the stainless steel pipe which was detected by means of spark emission spectrometer. (orig.)
Intensities of {gamma}-transitions emerging from the EC decay of {sup 203}Pb were measured precisely. The obtained relative {gamma}-intensities are 100%(279.2keV), 4.14+-0.08%(401.3keV) and 0.932+-0.022%(680.5keV). The 279.2 and 680.5keV level feeding {beta}-branching ratios were deduced to be 95.3+-0.1 and 4.7+-0.1% respectively. {sup 203}Pb is suggested for calibration purposes. (author).
Neutron deficient nuclei with mass numbers A {approx} 90 and 40 {<=} Z {<=} 44 have been studied making use of the Osiris and Nordball spectrometers. The high spin states of these nuclei and their electromagnetic decay properties are compared to shell model calculations based on the core {sup 88}Sr and using different parametrizations of the residual interaction. The dependence of the mean square deviations of experimental and theoretical level energies, branching ratios, and transition probabilities on the neutron numbers N = 46-50 and the validity of seniority as a good quantum number are discussed. (orig.).
Continuum events represent an eminent source of background in any e+e- experiment. As these have a higher branching ratio than BB-bar events (at BaBar this ratio is estimated to about 3.5) or ?+?- events, efficient continuum background suppression is essential in many analyses. Using Artificial Neural Networks and the Nearest Neighbor Method we developed several selectors which, based only on the global event shape variables, efficiently tag BB-bar events and ?+?- events against the continuum background. These selectors could then be combined with the channel specific information in various types of analyses. The study was done using a parametric Monte Carlo.
... So whatever banking issues you would like to discuss, there are a number of convenient ways to contact us. You write to us, phone one of our UK call centres, arrange a meeting with a financial adviser or, of course, visit your local branch. Telephone us Want to give us a call? Click here to see our full list of contact details. Remember, all our call centres are based in the UK. So we can deal with your call efficiently, please have all ...
The high temperature abrasive wear resistant of the composites with different Al{sub 2}O{sub 3} volume fractions, particle coating and size were investigated and the failure action of composites under different conditions at high temperature was analyzed. The results showed that the high temperature abrasive wear resistant of composite with Ni coating and wide size and 39% volume fraction of particle is the best among all composites examined. (orig.)
The results of the investigations show that magnetic treatment is a quite practical and effective method of intensifying certain technological processes in the coking industry. Magnetic treatment was utilized for improving the production of ammonium sulfate, refining of the naphthalene fraction, removal of sludge from wash oil in the benzol division, and the treatment of tar before fractionation. 2 references, 3 tables.
If 4-day-old dark-grown zucchini squash seedlings (Cucurbita pepo L. cv. Black Beauty) are exposed briefly to red light, subsequent cell fractionation yields about 40% of the total...Full Text Available
Nearly all chemical processes fractionate17O and 18O in a mass-dependent way relative to 16O, a major exception being the formation of ozone from diatomic oxygen in...Full Text Available
For the determination of the elemental composition of insoluble endogenous fractions from gastrointestinal tract by SRXRF (XRF experimental beam line, VEPP-3, INP SU RAS, Novosibirsk), an analytical method was developed for producing epithelial tissue in vivo. The metrological characteristics were determined using a number of international biological standards.
In normal subjects, apolipoprotein E (apo E) is present on very low density lipoproteins (VLDL) (fraction I) and on particles of a size intermediate between VLDL and low density lipoproteins (LDL) (fraction...Full Text Available
A design concept is presented for an in-bundle gamma densitometer system for measurement of subchannel average fluid density and void fraction in rod or tube bundles. This report describes (1) the application of the design concept to the Thermal-Hydraulic Test Facility (THTF) electrically heated rod bundle; and (2) results from tests conducted in the THTF.
Four solutions of the Cauchy problem for Mathieu?s equation away from parametric resonance domains are analytically constructed using an asymptotic averaging method in the fourth approximation. Three solutions occur near fractional parameter values at which slow combination phases exist. The fourth solution occurs in the absence of slow phases away from parametric resonance domains and the fractional parameter values.
To assess the influence of stent design [interlacing (type A) vs. crossing method (type B)] on neointimal hyperplasia using a self-expandable nitinol stent, which crosses the side branches of the abdominal aorta. In seven mongrel dogs, nitinol stents with type A and B intersections were placed in the abdominal aorta across the main branches: 4 Niti-Ms and 3 Niti-Ds. Two months after the stent placement, a DSA was performed for a stent patency evaluation, followed by the extraction of the aortas. The degree of neointimal formation along the wire was evaluated by calculating the area ratio of intimal hyperplasia (type A vs. B). A Student's t-test was employed to investigate the differences in the neointimal hyperplasia between blood types A and B. The total number of wire intersections overlain at the ostia branch ostia was 23 for type A and 36 for type B. The area ratio of the neointimal hyperplasia, for a given ...
Angle resolved valence shell photoelectron spectra of chloromethane and iodomethane have been recorded using synchrotron radiation in the photon energy range 14-120eV. These have allowed photoelectron angular distributions and branching ratios to be determined not only for the main bands associated with the single-hole states but also for the satellite structure due to many-electron effects. The continuum multiple scattering approach has been used to calculate photoelectron asymmetry parameters and branching ratios for the valence orbitals of CH_3Cl and CH_3I, and also for the I 4d subshell. A comparison between the experimental data and the theoretical predictions has enabled the influence of Cooper minima, shape resonances and intershell coupling to be assessed. The asymmetry parameters and branching ratio for the spin-orbit split components of the CH_3I"+X-bar "2E state have been measured and exhibit a spectral behaviour ...
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed Tomography (X-CT) system are used to determine the flow regime, the instantaneous cross-sectional averaged void fraction, and the time averaged void fraction in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements are obtained for gas flow rates form 0.0 to 30.0 l/min. The flow regimes observed by all three measurement systems via image analysis shows that the results agree well with each other. Both the RTNR and the X-CT systems show that the time averaged and cross-sectional averaged void fraction increases with increasing superficial gas velocity. Time and cross-sectional averaged void fractions determined by the RTNR system agree within 4% with those determined by the high speed X-ray CT technique. ...
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed Tomography (X-CT) system are used to determine the flow regime, the instantaneous cross-sectional averaged void fraction, and the time averaged void fraction in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements are obtained for gas flow rates form 0.0 to 30.0 l/min. The flow regimes observed by all three measurement systems via image analysis shows that the results agree well with each other. Both the RTNR and the X-CT systems show that the time averaged and cross-sectional averaged void fraction increases with increasing superficial gas velocity. Time and cross-sectional averaged void fractions determined by the RTNR system agree within 4% with those determined by the high speed X-ray CT technique. ...
Two experiments were conducted to evaluate the effect of compost addition to soil on fractionation and bioavailability of Cu, Mn, and Zn to four crops. Soils growing Swiss chard (Beta vulgaris var. cicla L.) and basil (Ocimum basilicum L.) were amended (by volume) with 0, 20, 40, and 60% Source-Separated Municipal Solid Waste (SS-MSW) compost, and dill (Anethum graveolens L.) and peppermint (Mentha X piperita L.) were amended with 0, 20, 40, and 60% of high-Cu manure compost (by volume). The SS-MSW compost applications increased the concentration of Cu and Zn in all fractions, increased Mn in acid extractable (ACID), iron and manganese oxides (FeMnOX), and organic matter (OM) fractions, but decreased slightly exchangeable-Mn. Addition of 60% high-Cu manure compost to the soil increased Cu EXCH, ACID, FeMnOX, and OM fractions, but decreased EXCH-Mn, and did not change EXCH-Zn. Addition of both composts ...
The relative roles of glomerular filtration, tubular reabsorption and tubular secretion in lead handling were evaluated using renal clearance technique, stop-flow analysis, and renal lead accumulation. In addition, the effect of altering acid-base status on renal handling of Pb was determined. Clearance of ultrafilterable lead was measured in anesthetized dogs during infusion of "2"0"3Pb with small doses of carrier Pb(0.5 to 50 #mu#g/kg/h). Filterable lead concentration was estimated by in vitro ultrafiltration of non-anticoagulated plasma. Fractional excretion of Pb was calculated using creatinine clearance to estimate glomerular filtration rate. Dogs in acute metabolic acidosis had the lowest fractional excretion of ultrafilterable Pb (< 0.1); those in alkalosis had high fractional Pb excretion (0.75 to 2.5) while normal dogs were intermediate (0.1 to .4). The fractional excretion of Pb during ...
A Real-Time Neutron Radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a CANDU-type 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the CANDU-type rod bundles. A new flow regime is observed and designated Large Amplitude Stratified Wavy flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occurring in the bundle. The rods in the bundle may act as a dampener to the vertical flow and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the circumferential ...
A real-time neutron radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a cylindrical 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the cylindrical rod bundles. A new flow regime is observed and designated large amplitude stratified wavy (LASW) flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occuring in the bundle. The rods in the bundle may act as a dampener to the vertical flow component and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the ...
A Real-Time Neutron Radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a CANDU-type 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the CANDU-type rod bundles. A new flow regime is observed and designated Large Amplitude Stratified Wavy flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occurring in the bundle. The rods in the bundle may act as a dampener to the vertical flow and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the circumferential ...
In searching modulators of immunity and hematopoiesis among natural products, being used as foods, six herbs exhibited lymphocyte proliferation in vitro, and six exhibited augmentation of hematopoietic cell growth. The combined treatments showed synergistic effects of lymphocyte proliferation and of hematopoietic cell growth. On the other hand, we found four effective oriental medicinal prescriptions, used as energy tonic or blood-building decoctions, for survival and regeneration of hematopoietic cells and for protection of stem cells of intestinal crypt in irradiated mice. On the basis of these results, extracts from combinations of herbs were made in expectation of higher effects in the three respects. In immuno modulation activity by the two combinations of herbs was confirmed in mice. In culture of bone narrow cells, growth improvement of non-adherent precursor and induction of cytokine expression by herb mixture extracts were observed. In evaluation of ...
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed tomography (X-CT) system are compared for measurement of two-phase flow. Each system is used to determine the flow regime, and the void fraction distribution in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements obtained for gas flow rates from 0.0 to 30.01/min. The flow regimes observed by all three measurement systems through image analysis shows that the two-dimensional void fraction distribution can be obtained. The X-CT system is shown to have a superior temporal resolution capable of resolving the void fraction distribution in an (r,{theta}) plane in 33.0 ms. Void fraction distribution for bubbly flow and slug flow is determined.
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed tomography (X-CT) system are compared for measurement of two-phase flow. Each system is used to determine the flow regime, and the void fraction distribution in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements obtained for gas flow rates from 0.0 to 30.01/min. The flow regimes observed by all three measurement systems through image analysis shows that the two-dimensional void fraction distribution can be obtained. The X-CT system is shown to have a superior temporal resolution capable of resolving the void fraction distribution in an (r,#theta#) plane in 33.0 ms. Void fraction distribution for bubbly flow and slug flow is determined.
A stable isotope mass-balance of dissolved inorganic carbon during a blue-green algae bloom in a softwater lake demonstrates that at low partial pressure of carbon dioxide there must be a large net negative carbon isotope fractionation between atmospheric CO/sub 2/ and the CO/sub 2/ absorbed by lake water at pH = 9.5. Chemical enhancement of CO/sub 2/ invasion at high pH by the reaction CO/sub 2/ + OH/sup -/ ..-->.. HCO/sub 3//sup -/ at large apparent film thicknesses may result in carbon isotope fractionation approaching that for a hydroxide solution. This phenomenon, coupled with a decrease in the photosynthetic fractionation, forced the surface water of a softwater lake to achieve increasingly negative delta /sup 13/C values during an algal bloom, which is in the opposite sense to the trend that results from photosynthesis under less extreme conditions. This and other similar systems must operate under non-equilibrium ...
An effective computer program for three dimensional relativistic hydrodynamical model has been developed. It implements a new approach to the early hot phase of relativistic heavy-ion collisions. The computer program simulates time-space evolution of nuclear matter in terms of ideal-fluid dynamics. Equations of motions of hydrodynamics are solved making use of finite difference methods. Commonly-used algorithms of numerical relativistic hydrodynamics RHLLE and MUSTA-FORCE have been applied in simulations. To speed-up calculations, parallel processing has been made available for solving hydrodynamical equations. The test results of simulations for 3D, 2D and Bjorken expansion are reported in this paper. As a next step we plan to implement the hadronization algorithm by implementing the continuous particle emission for freeze-out and comparing it with Cooper-Frye formula.
The measurements performed at CERN on prototypes and first pre-series main dipole magnets confirm the need of an active control of the Large Hadron Collider to compensate the dynamic field changes during the proton beam injection and acceleration. This control requires in turn an accurate forecast of the magnetic field in the accelerator. We plan to predict the field on the basis of two elements: theoretical field models tailored through the accumulated knowledge of the main magnets during series tests, and an on-line measurement system running on few reference magnets tracking the LHC current cycle. Data coming from this "Multipoles Factory" will result from the fusion of the two sources. Based on this system we foresee to deliver calibration information for pre-defined accelerator cycles as well as real time information for the active control. In this paper we report the conceptual design of the system, and we discuss the features and performance of the models ...
We estimate the TeV {gamma}-ray fluxes expected from the population of young pulsars in terms of the self-consistent time-dependent hadronic-leptonic model for the high-energy processes inside the pulsar wind nebulae (PWNe). This radiation model is based on the hypothesis of Arons and collaborators who postulate that leptons are accelerated inside the nebulae as a result of resonant scattering on heavy nuclei, which in turn are accelerated in the pulsar wind region or the pulsar inner magnetosphere. Our aim is to find out which PWNe on the northern hemisphere are the best candidates for detection at energies above 60 GeV and 200 GeV by the next generation of low-threshold Cherenkov telescopes.
An apparently significant result in an experiment to search for tachyons in the interval of time immediately preceding the arrival of air showers of energy greater than 10"1"5 eV has been reported by Clay and Crouch (Clay, R.W. and Crouch, P.C., 1974, Nature, vol.248,28-30). Several similar experiments have been completed, all of which have yielded null results. The original data of Clay and Crouch have been re-examined and it is shown that an artifact of the apparatus was contributing to the original, apparently significant, result. An upper limit estimate shows that the number of tachyons is less than the number of hadrons of energy greater than 100 GeV in showers of average size N = 6 x 10"5 particles. (author).
In pp collisions at 1.25 GeV kinetic energy, the HADES collaboration aimed at investigating the di-electron production related to $\\Delta$ (1232) Dalitz decay ($\\Delta^+ \\to pe^+e^-$). In order to constrain the models predicting the cross section and the production mechanisms of $\\Delta$ resonance, the hadronic channels have been measured and studied in parallel to the leptonic channels. The analyses of $pp\\to np\\pi^+$ and $pp\\to pp\\pi^0$ channels and the comparison to simulations are presented in this contribution, in particular the angular distributions being sensitive to $\\Delta$ production and decay. The accurate acceptance corrections have been performed as well, which could be tested in all the phase space region thanks to the high statistic data. These analyses result in an overall agreement with the one-$\\pi$ exchange model and previous data.
Inclusive double spin asymmetries obtained by scattering polarized electrons off polarized protons and deuterons have been analyzed to address the issue of quark-hadron duality in the polarized spin structure functions g^p_1 and g^d_1. A polarized electron beam, solid polarized NH_3 and ND_3 targets and the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B were used to collect the data. The resulting g^p_1 and g^d_1 were averaged over the nucleon resonance energy region (M < W < 2.00 GeV), and three lowest lying resonances individually for tests of global and local duality.
For the preparation of photonic probes for hadron physics the determination of energy and polarization of the photons is essential. In this dissertation in a first part a possibility of the determination of the degree of polarization by use of the asymmetry observables is presented. In a second part a possibility isd discussed to perform an energy and polarization tagging of nearly real photons in electron scattering under small Q{sup 2}. By this method it should be possible to tag billions of photons per second.
The proposed Superconducting Super Collider (SSC) in the US and plans for a Large Hadron Collider LHC at CERN are likely to require micron size filaments to reduce micron size filaments to reduce magnetization effects at the low injection fields envisioned. Superconductors of NbTi, designed to meet these requirements, are described. These conductors contain from 6000 to 36,613 filaments. Results are presented on NbTi conductors made by multiple extrusion techniques. Filament sizes of between 2.2 and 17 micron have been obtained. Current densities of between 2400 A/mm"2 and nearly 3400 A/mm"2 at 5 Tesla have been achieved. Metallurgical aspects of these conductors are presented using both optical and SEM views of conductor cross section and filament surface.
We investigate the semihard production of neutral pseudoscalar and tensor mesons in high-energy [gamma][gamma] collisions (M=P=[pi][sup 0], [eta], [eta]' or M=T=a[sub 2], f[sub 2], f[sub 2]'). We deal with the exclusive [gamma][gamma][yields]MM' or semi-exclusive [gamma][gamma][yields]MX reactions (X is the hadron jet with not too large mass). The considered transfer momenta are small in comparison with the photon energies and they are large in comparison with the confinement scale. The amplitudes of these processes are determined by the odderon exchange, i.e. three-gluon exchange in the lowest order of perturbative QCD. The cross sections are calculated in this approximation. The possibility of measurements at LEP and at future [gamma][gamma] colliders is discussed. (orig.).
This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory Editing and changes to the authors` contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on nine presentations: ``The Energy Exchange and Efficiency Consideration in Klystrons``, ``Some Properties of Microwave RF Sources for Future Colliders + Overview of Microwave Generation Activity at the University of Maryland``, ``Field Quality Improvements in Superconducting Magnets for RHIC``, ``Hadronic B-Physics``, ``Spiking Pulses from Free Electron Lasers: Observations and Computational Models``, ``Crystalline Beams in Circular Accelerators``, ``Accumulator Ring for AGS & Recent AGS Performance``, ``RHIC Project Machine Status``, and ``Gamma-Gamma Colliders.``
The ATLAS High Level Trigger (HLT) is a distributed real-time software system that performs the final online selection of events produced during proton-proton collisions at the Large Hadron Collider (LHC). It is designed as a two-stage trigger and event filter running on a farm of commodity PC hardware. Currently the system consists of about 850 processing nodes and will be extended incrementally following the expected increase in luminosity of the LHC to about 2000 nodes. The event selection within the HLT applications is carried out by specialized reconstruction algorithms. The selection can be controlled via properties that are stored in a central database and are retrieved at the startup of the HLT processes, which then usually run continuously for many hours. To be able to respond to changes in the LHC beam conditions, it is essential that the algorithms can be re-configured without disrupting data taking while ensuring a consistent and reproducible ...
The current status of rare B decays is reviewed based on recent observation of the penguin-diagram decay B {yields} K{sup *}{gamma} at CLEO. Rare B decays provide valuable information on the Standard Model parameters, and also could be a source of direct CP violation. It is emphasized that new physics beyond the Standard Model can appear in rare B decays, in some cases more drastically than in the CP Asymmetry of the B system. Inclusive measurement of the radiative transition b {yields} s{gamma} is promising. Hadronic penguin modes are very close to being observed at CLEO, and a discovery might be just around the corner. (author). 48 refs., 6 figs., 4 tabs.
Quartz fiber calorimetry is a technique the signal generation mechanism of which is based on the Cherenkov effect. In this article we try to give a comprehensive overview of the subject. We start with a general introduction to calorimetry where the basic elements that characterize the development of electromagnetic and hadronic showers are discussed. Then we describe in detail the operation principle and the properties of calorimeters equipped with quartz fibers. The main advantages of this type of calorimeters are the radiation hardness, the fast response and the compact detector dimensions, features that derive from the quartz material and the specific mechanism of operation. A section is devoted to presenting the quartz fiber calorimeters that have been built or planned to in various experiments to operate as centrality detectors, trigger detectors, luminosity monitors or general purpose very forward calorimeters.
We compute QCD corrections to the production of a ttbar pair in association with a hard photon at the Tevatron and the LHC. This process allows a direct measurement of the top quark electromagnetic couplings that, at the moment, are only loosely constrained. We include top quark decays, treating them in the narrow width approximation, and retain spin correlations of final-state particles. Photon radiation off top quark decay products is included in our calculation and yields a significant contribution to the cross-section. We study next-to-leading order QCD corrections to the ppbar -> ttbar+gamma process at the Tevatron for the selection criteria used in a recent measurement by the CDF collaboration. We also discuss the impact of QCD corrections to the pp -> ttbar+gamma process on the measurement of the top quark electric charge at the 14 TeV LHC.
At the quark level there are basically two types of contributions of R-parity violating supersymmetry (Rep SUSY) to neutrinoless double beta decay: the short-range contribution involving only heavy virtual superpartners and the long-range one with the virtual squark and neutrino. Hadronization of the effective operators, corresponding to these two types of contributions, may in general involve virtual pions in addition to close on-mass-shell nucleons. From the previous studies it is known that the short-range contribution is dominated by the pion exchange. In the present paper we show that this is also true for the long-range Rep SUSY contribution. Therefore, we conclude that the Rep SUSY contributes to the neutrinoless double beta decay dominantly via charged pion exchange between the decaying nucleons.
Heavy Ion Collisions at RHIC and LHC energies are potentially an interesting laboratory for the study of QED. In these collisions, a Heavy Ion in one beam sees a highly Lorentz contracted electric field due to an oncoming beam particle. The Electric field reaches a maximum value of E {approx_equal} {gamma}{sub eff} {center_dot} Z {center_dot} e/b{sup 2}, where the apparent Lorentz factor, {gamma}{sub eff} = 2 {center_dot} {gamma}{sub beam}{sup 2} - 1. The collision may be viewed in terms of a flux of photons colliding with a stationary ion target using the equivalent photon approximation, originally introduced by Fermi in 1924. We show that the cross section for Inelastic Electromagnetic Interactions of Heavy Ions are both calculable and have been measured in the first RHIC running period.
The RD50 collaboration has been exploring the development of radiation hard semiconductor devices for very high-luminosity colliders since 2002. The target fluence to qualify detectors set by the anticipated dose for the innermost tracking layers of the future upgrade of the CERN large hadron collider (LHC) is 1016 1 MeV neutron equivalent (neq) cm-2. This is about an order of magnitude higher than the maximum dose for the most exposed silicon detectors in the current machine. RD50 investigates the radiation hardening of silicon sensors from many angles: improvement of the intrinsic tolerance of the substrate material, optimisation of the readout geometry and study of novel design of detectors. A review of some of the recent activities within RD50 is here presented.
The RD50 collaboration has been exploring the development of radiation hard semiconductor devices for very high-luminosity colliders since 2002. The target fluence to qualify detectors set by the anticipated dose for the innermost tracking layers of the future upgrade of the CERN large hadron collider (LHC) is 1016 1MeV neutron equivalent (neq) cm-2. This is about an order of magnitude higher than the maximum dose for the most exposed silicon detectors in the current machine. RD50 investigates the radiation hardening of silicon sensors from many angles: improvement of the intrinsic tolerance of the substrate material, optimisation of the readout geometry and study of novel design of detectors. A review of some of the recent activities within RD50 is here presented.
MINER?A is a high resolution, fully active detector designed to study neutrino interactions on nuclei in the NuMI beam at Fermi National Accelerator Laboratory. The active volume of the detector consists of 3 tons of plastic scintillator and includes embedded targets of 4He, C, H2O, Fe and Pb. The MINER?A collaboration expects to perform precision, A-dependent neutrino cross section measurements in the 1?10 GeV region, measure the axial form factor, and study nuclear shadowing of F2, quark-hadron duality and coherent pion production, among other topics. MINER?A began data taking in the fall of 2009. This paper describes the MINER?A experiment and provides an overview of the physics objectives along with estimated uncertainties of the measurements and the tentative projected schedule of dat...
The AdS/CFT correspondence is a powerful tool to study the properties of conformal QCD at strong coupling in terms of a higher dimensional dual gravity theory. The power-law falloff of scattering amplitudes in the non-perturbative regime and calculable hadron spectra follow from holographic models dual to QCD with conformal behavior at short distances and confinement at large distances. String modes and fluctuations about the AdS background are identified with QCD degrees of freedom and orbital excitations at the AdS boundary limit. A description of form factors in space and time-like regions and the behavior of light-front wave functions can also be understood in terms of a dual gravity description in the interior of AdS.
A reduction of the mass of the \\eta'(958) meson may indicate the restoration of the UA(1) symmetry in a hot and dense hadronic matter, corresponding to the return of the 9th, "prodigal" Goldstone boson. We report on an analysis of a combined PHENIX and STAR data set on the intercept parameter of the two-pion Bose-Einstein correlation functions, as measuremed in \\sqrt{s_NN} = 200 GeV Au+Au collisions at RHIC. To describe this combined PHENIX and STAR dataset, an in-medium \\eta' mass reduction of at least 200 MeV is needed, at the 99.9 % confidence level in a broad model class of resonance multiplicities. Energy, system size and centrality dependence of the observed effect is also discussed.
The postulate that negative-energy particles do not exist (travelling forward in time) leads automatically to the 'Reinterpretation Principle' by Stueckelberg and by Feynman. It has been already shown that such a 'principle', assumed as the Third postulate of special relativity, ensures the validity of the law of (retarded) casuality both in standard relativity and in (extended) relativity with tachyons and with Superluminal inertial frames. Our Thir postulate, moreover, allows predicting antiparticle existence in a purely relativistic context. In this paper it is shown that the Third postulate is enough to implement the law of casuality even in macrophysics, when usual macro-objects interact with micro-tachyons and macrotachyons. To that aim, some tachyon kinematics is further developed, which can be useful even in understanding elementary-particle interactions (and may be hadron structure). Many other related problems are discussed.
We study neutral and charged Higgs boson production in association with stop and sbottom squarks at the Large Hadron Collider (LHC), within the so-called M-SUGRA scenario, i.e., the Supergravity (SUGRA) inspired Minimal Supersymmetric Standard Model (MSSM). For low values of \\tan\\beta only the cases \\tilde{t}_1\\tilde{t}_1^* H, \\tilde{t}_1\\tilde{t}_1^* h and than 30 a variety of signals involving all Higgs bosons can be accessed, at high collider luminosity. The dependence of these reactions on the M-SUGRA parameters might further allow one to pin down the actual structure of the underlying Supersymmetric (SUSY) model.
An analysis of the cross section for hadronic production of gluino-squark pairs close to threshold is presented. Within the framework of non-relativistic QCD a significant enhancement compared to fixed order perturbation theory is observed which originates from the characteristic remnants of the gluino-squark resonances below the nominal pair threshold. The analysis includes all colour configurations of S-wave gluino-squark pairs, i.e. triplet, sextet and 15 representation. Matching coefficients at leading order are separately evaluated for all colour configurations. The dominant QCD corrections, arising from initial- and final-state radiation are included. The non-relativistic dynamics of the gluino pair is solved by calculating the Green's function in Next-to-Leading Order (NLO). The results are applied to benchmark scenarios, based on Snowmass Points and Slopes (SPS). As a consequence of the large decay rate of at least one of the constituents squark or gluino ...
We compute the corrections from two-photon and {gamma}-Z exchange in parity-violating elastic electron-proton scattering, used to extract the strange form factors of the proton. We use a hadronic formalism that successfully reconciled the earlier discrepancy in the proton's electron to magnetic form factor ratio, suitably extended to the weak sector. Implementing realistic electroweak form factors, we find effects of the order 2%-3% at Q{sup 2} < or approx. 0.1 GeV{sup 2}, which are largest at backward angles and have a strong Q{sup 2} dependence at low Q{sup 2}. Two-boson contributions to the weak axial current are found to be enhanced at low Q{sup 2} and for forward angles. We provide corrections at kinematics relevant for recent and upcoming parity-violating experiments.
A pillbox RF output window was developed for the L-band pulsed klystron for the Japanese Hadron Project (JHP) 1-GeV proton linac. The window was designed to withstand a peak RF power of 6 MW, where the pulse width is 600 {mu}sec and the repetition rate is 50 Hz. A high power model was fabricated using an alumina ceramic which has a low loss tangent of 2.5x10{sup -5}. A high power test was successfully performed up to a 113 kW RF average power with a 4 MW peak power, a 565 {mu}sec pulse width and a 50 Hz repetition rate. By extrapolating the data of this high power test, the temperature rise of the ceramic is estimated low enough at the full RF power of 6 MW. Thus this RF window is expected to satisfy the specifications of the L-band Klystron. (author).
A data analysis based on an artificial neural network classifier is proposed to identify cosmic ray antiprotons detected with the CAPRICE silicon-tungsten imaging calorimeter against electron background in the energy range 1.2-4.0 GeV. A set of new physical variables, describing the events inside the calorimeter on the base of their different patterns, are introduced in order to discriminate between hadronic and electromagnetic showers. The ability of the artificial neural network classifier to perform a careful multidimensional analysis gives the possibility to identify antiprotons with an electron rejection 408{+-}85 (stat) at 95.0{+-}0.2 (stat)% of signal detection efficiency. The high accuracy achieved by this method improves substantially the efficiency in the evaluation of the cosmic ray antiproton spectrum. (orig.).
Energy flows in deep inelastic electron-proton scattering are investigated at a centre-of-mass energy of 296 GeV for the range Q{sup 2}{>=}10 GeV{sup 2} using the ZEUS detector. A comparison is made between events with and without a large rapidity gap between the hadronic system and the proton direction. The energy flows, corrected for detector acceptance and resolution, are shown for these two classes of events in both the HERA laboratory frame and the Breit frame. From the differences in the shapes of these energy flows we conclude that QCD radiation is suppressed in the large-rapidity-gap events compared to the events without a large rapidity gap. (orig.)
A large hadron machine like the LHC with its high track multiplicities always asks for powerful tools that drastically reduce the large background while selecting signal events efficiently. Actually such tools are widely needed and used in all parts of particle physics. Regarding the huge amount of data that will be produced at the LHC, the process of training as well as the process of applying these tools to data, must be time efficient. Such tools can be multivariate analysis -- also called data mining -- tools. In this contribution we present the results for the application of the multivariate analysis, rule growing algorithm RIPPER on a problem of particle selection. It turns out that the meta-methods bagging and cost-sensitivity are essential for the quality of the outcome. The results are compared to other multivariate analysis techniques.
The {rvec n} + p {yields} d + {gamma} experiment under construction at LANSCE studies the weak interaction between neutrons and protons. The experiments will measure the directional dependence of the parity-violating {gamma}-ray asymmetry, A{sub {gamma}}, in the polarized cold neutron capture by para-hydrogen. The goal is to measure A{sub {gamma}} with uncertainty of 0.5 x 10{sup -8}, 10% of its predicted value. A{sub {gamma}} primarily isolates the {Delta}I = 1 component of the hadronic weak interaction and thus will determine the long-range weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. The experiment is carefully designed for the LANSCE pulsed spallation neutron source to achieve the proposed statistical precision and to control systematic errors. We discuss the experiment and its status.
An evaporative cooling system developed for operation and qualification testing of silicon pixel and microstrip detectors for the inner tracking detector of the CERN ATLAS spectrometer is described. Silicon detector substrates must be continuously operated between 0 and ???7?C in the high radiation environment near the circulating beams at the CERN Large Hadron Collider (LHC). This requirement imposes unusual constraints on the cooling system and has led to the choice of perfluoro-n-propane (C3F8) refrigerant, which combines good chemical stability under ionizing radiation with high dielectric strength and nonflammability. Since the silicon detectors must also be of extremely light construction to minimize undesirable physics background, coolant tubes are of thin (200 ?m) aluminum wall, wh...
LECTURE SERIES 14, 15, 17 January 2008 11:00 to 12:00 - Council Chamber, bldg. 503-1-001 Applications of accelerators to tumour therapy U. AMALDI, TERA Foundation & University of Milano Bicocca The first lecture is devoted to an historical review of the developments of the teletherapy techniques which make use of hadron beams and are collectively called "hadrontherapy". The main emphasis is on the use of protons and light ions, but also neutrons, pions and antiprotons are considered. The second lecture reviews the rationale behind the use of carbon ions in the treatment of radioresistant tumours and the results obtained both with proton and carbon ion beams on the 60 000 patients treated worldwide. The numbers of patients who would profit from hadrontherapy are presented together with the current landscape of running and planned hospital based centres. The main technical challenges set by this therapeutic modality are discussed in the third lecture together ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (I.D.: 4.08 mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final results ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (inner diameter; 4.08mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3 M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (I.D.: 4.08 mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final results ...
Real-time neutron radiography has been used to study the dynamic behavior of two-phase flow and measure vapor fractions in a steam-water duct at atmospheric pressure. This unique experimental technique offers one the opportunity to observe and record on videotape now Patterns and transient behavior of two-phase flow inside opaque containers without perturbing the environment. The neutron radiographic technique is non-intrusive and requires no special transparent window region. Data are recorded simultaneously over a large area of interest. Image processing of the video data can be employed to measure bubble velocities and time-averaged and Instantaneous vapor fractions.
This paper describes a series of tests investigating two-phase flow regimes in a transparent model of a PWR hot leg. Test conditions were selected to cover a wide range of gas and liquid superficial velocities (.01 m/s 2 m/s) were also performed for comparison with semi-analytical predictions. Results include average void fractions, flow rates, and visual characterizations of the two-phase flow phenomena. Results show generally good agreement with Taitel and Duckler flow regime map and Zuber-Findlay correlation for average void fraction in vertical pipes. Results also indicate that flow regimes and collapsed liquid level (void fraction) are more strongly dependent on air flow rate (air superficial velocity) than water flow rate (water superficial velocity).
Molar excess volumes have been determined by means of a vibrating-tube densimeter for binary liquid mixtures of cycloalkanones (cyclopentanone and cyclohexanone) + cyclohexane, + benzene, and + tetrachloromethane. The V/sup E/ data are reported over the complete mole fraction range at 288.15, 298.15, and 308.15{Kappa}. The obtained excess volumes are positive for mixtures of cyclopentanone with cyclohexane and are negative for mixtures of the cycloalkanones with benzene and tetrachloromethane; for the system cyclohexanone-cyclohexane the V/sup E/ values are positive for a wide range of mole fraction, but at very low cyclohexane mole fraction an inversion of the sign of V/sup E/ is observed. The data show that in the considered range of temperature the values of the temperature coefficient ({partial derivative}V/sup E//{partial derivative}T) are negative for mixtures of the cycloalkanones with benzene and are almost zero for ...
The state of prooxidant-antioxidant homeostasis in Guinea pigs exposed to whole-body fractionated X-irradiation (5 fractions of 0.2 Gy at a 24 hr interval, up to total dose of 1.0 Gy, at a dose rate of 0.425 R/min) and a possibility of its disturbance correction with the complex of vitamins C, E and P was studied. Accumulation of primary and secondary lipid peroxidation products, decrease of the ascorbic acid content, increase of the content of its oxidized forms (dehydroascorbic acid and diketogulonic acid) in radiosensitive and radioresistant organs were found. Antioxidant complex administration reduced the disturbances of prooxidant-antioxidant homeostasis, but did not provide complete normalization.
Simple, one-zone models for inhomogeneous chemical evolution of the Galactic halo are used to predict the number fraction of zero-metallicity, Population III stars, which currently is empirically estimated at < 4e-4. These analytic models minimize the number of free parameters, highlighting the most fundamental constraints on halo evolution. There are disagreements of at least an order of magnitude between observations and predictions in limiting cases for both homogeneous Simple Model and Simple Inhomogeneous Model (SIM). Hence, this demonstrates a quantitative, unambiguous discrepancy in the observed and expected fraction of Population III stars. We explore how the metallicity distribution of the parent enrichment events f(z_0) drives the SIM and predictions for the Population III fraction. The SIM shows that the previously-identified "high halo" and "low halo" populations are consistent with a continuous evolutionary ...
Two rapidly solidified powders with compositions Al-6.7 wt.% Fe-5.9 wt.% Ce and Al-6.2 wt.% Fe-5.9 wt.% Ce-1.63 wt.% Si were separated into -32 [mu]m and +32 to -63 [mu]m size fractions. Powders from both size fractions were extruded at 500 C. For comparison purposes, extrusion at a lower temperature of 400 C was also performed. In this investigation, tensile property evaluation indicated that processing of finer size fractions at high temperature offers no advantages in terms of the tensile properties but is advantageous in terms of improving the fracture toughness of alloy B. These observations underline the importance of the stability of powder microstructure during thermomechanical processing for the development of optimum mechanical properties. (orig.)
The environmental behavior of antibiotics has attracted great research attention. However, their sorption mechanisms in soils/sediments are still unknown. Comparison of the sorption properties between the widely-studied hydrophobic organic contaminants (HOCs) and antibiotics may provide valuable insight to antibiotic sorption mechanisms. Thus, in this study batch experiments for pyrene (PYR), bisphenol A (BPA), and sulfamethoxazole (SMX) sorption were conducted on a sediment sample and its separated fractions. Our results showed the high sorption of PYR on black carbon and organic matter. Although high sorption of SMX was observed for both separated organic fractions (humic acids) and inorganic mineral particles, the original sediment particles showed relatively low sorption. Competitive s...
Depending on the soil environment, selenium (Se) can exist as several species differing greatly in bioavailability. Characterization of soil Se reserves is thus necessary in assessing the nutritional supply of this essential element. In low-Se areas, Se fertilization is an option for securing adequate Se nutrition. Fertilization is, however, challenged by the unknown fate of the residual Se. In this study, we aimed to clarify the Se status of selenate-fertilized field soils by fractionating soil Se into five pools: salt-soluble (KCl), adsorbed (KH2PO4/K2HPO4), organically associated (NaOH), elemental (Na2SO3) and recalcitrant Se (NaOCl). Changes induced in these fractions by repeated application of low selenate doses were examined by comparing samples collected from the same locations in 1...
All measurements were made with the NBS high-pressure photoionization mass spectrometer. The fractional of C/sub 5/H/sub 10//sup +/ions in a cyclopentane-cyclohexane mixture were determined as a function of pressure in order to define the fraction of the ions which did charge exchange with cyclohexane; i.e. the fraction which remained cyclic after ionization. The data for mixtures of various compositions (2.5 to 10% cyclohexane) are summarized for measurements performed at 10.62 eV: (a) 292K, > 96% cyclic; 347 K, greater than or equal to 94% cyclic; 386 K, 84 +- 4% cyclic; and 412 K, 78 +- 6% cyclic; entropy, enthalpy, and activation energy were determined; 10.49 eV was obtained as the ionization potential of cyclopentane. 1 figure.
Protein kinase C activity has been identified in the rat brown adipocyte. About 60% of this activity is found in the cytosolic fraction under basal conditions, and 12-O-tetradecanoylphorbol 13-acetate (TPA) causes a rapid shift from the cytosol to the particulate fraction. Norepinephrine and phenylephrine causes a similar redistribution that can be blocked by prazosin but not by alprenolol. {alpha}{sub 1}-Adrenergic agonists cause three- to fivefold stimulation of type 2 iodothyronine 5{prime}-deiodinase activity in brown adipocytes. TPA has no effect on basal deiodinase activity and reduces the response of the enzyme to {alpha}{sub 1}-adrenergic agonists. These results suggest that the translocation of protein kinase C from cytosol to particulate fraction is not sufficient to increase deiodinase activity but can modulate the {alpha}{sub 1}-adrenergic agonist-mediated responses in these cells.
The factors influencing premixed burning and the importance of premixed burning on the exhaust emissions from a small high-speed direct-injection diesel engine were investigated. The characteristics of premixed and diffusion burning were examined using a single-zone heat-release analysis. The mass of fuel burned in premixed combustion was found to be linearly related to the product of engine speed and ignition-delay time and to be essentially independent of the total amount of fuel injected. Accordingly, the premixed-burned fraction increased with increasing engine speed, with decreasing fuel-air ratio and with retarding injection timing. The hydrocarbon emissions did not correlate well with the premixed-burned fraction. In contrast, the oxides of nitrogen emissions were found to increase with decreasing premixed-burned fraction, indicating that diffusion burning, and not premixed burning, is the primary source of oxides of ...
On the basis of a numerical model, the temperature and liquid fraction of spray-formed H13 tool steel are calculated as a function of time. Results show that a preheated substrate at the appropriate temperature can lead to very low porosity by increasing the liquid fraction in the deposited steel. The calculated cooling rate can lead to a microstructure consisting of martensite, lower bainite, retained austenite, and proeutectoid carbides in as-spray-formed material. In the temperature range between the solidus and liquidus temperatures, the calculated temperature of the spray-formed material increases with increasing substrate preheat temperature, resulting in a very low porosity by increasing the liquid fraction of the deposited steel. In the temperature region where austenite decomposit...
Fractionation of isotopes of the alkali metals and the alkaline earth metals in ion exchange chromatography of their chlorides was studied. The heavier isotopes of potassium and rubidium were found to be preferentially fractionated into the ion exchanger phase while the lighter isotopes of lithium, magnesium, calcium and strontium were enriched in the exchanger phase. This can be interpreted as a resultant of the relative significance of isotope effect upon dehydration and isotope effect accompanying the phase change of the hydrated metal ion. Found was no evidence of anomalous isotope effect attributable to the odd-even difference in mass number of isotopes. Based on the spectroscopic and solution chemical data (experimental and theoretical), the isotopic reduced partition function ratios of the hydrated alkaline metal ions and stretching force constants of metal ion-hydrating water bonds were estimated. (author).
The effects of five extraction solvents and their mixtures on the yield of metabolites in crude and fractionated extracts of Annona muricata L. leaves were investigated by direct comparison. Extraction media were prepared using simplex centroid mixtures of ethanol, ethyl acetate, dichloromethane, acetone, and chloroform. The effects of the mobile phase solvent strength and the analysis wavelength on the chromatographic separation were also investigated. Solvent mixtures rather than pure solvents were found to be the most efficient extractors for the different fractions. The results indicated that the mobile phase composed of methanol/acetonitrile/water (26:27:47 v/v/v) was most suitable for the basic fraction analysis at 254 nm, whereas the mobile phase composed of methanol/acetonitrile/wa...
Neutron radiography systems are being used for real-time visualization of the dynamic behavior as well as time-averaged measurements of spatial vapor fraction distributions for two phase fluids. The data in the form of video images are typically recorded on videotape at 30 frames per second. Image analysis of he video pictures is used to extract time-dependent or time-averaged data. The determination of the average vapor fraction requires averaging of the logarithm of time-dependent intensity measurements of the neutron beam (gray scale distribution of the image) that passes through the fluid. This could be significantly different than averaging the intensity of the transmitted beam and then taking the logarithm of that term. This difference is termed the dynamic error (error in the time-averaged vapor fractions due to the inherent time-dependence of the measured data) and is separate from the static error (statistical ...
In the past shredder fluff from automobile recycling was discarded in landfills, but shrinking landfill space and the partly hazardous content of the fluff as well as its caloric value, all resulted in efforts to turn this waste problem into an energy resource. In order to produce a fuel, the inorganic compounds have to be removed. Extensive analyses and particle size measurements were made on fluff from various shredder. For optimal separation all particles are reduced to a uniform, relatively small size. In a subsequent combined screening and air classification process, successful separation into organic and inorganic fractions is achieved. The inorganic fraction is treated in a heavy media or an eddy-current separator to recover the valuable metals, while the organic fraction is now suitable for thermal processing, such as fluidized bed gasification and using the resulting carbon as a chemical reagent.
An estimate for the number of ionizing photons per baryon as a function of redshift is computed based on the plausible extrapolation of the observed galaxy UV luminosity function and the latest results on the properties of the escape fraction of ionizing radiation. It is found that, if the escape fraction for low mass galaxies (Mtot<10^{11}Msun) is assumed to be negligibly small, as indicated by numerical simulations, then there are not enough ionizing photons to reionize the universe by z=6 for the cosmology favored by the WMAP 3rd year results, while the WMAP 1st year cosmology is marginally consistent with the reionization requirement. The escape fraction as a function of galaxy mass would have to be constant to within a factor of two for the whole mass range of galaxies for reionization to be possible within the WMAP 3rd year cosmology.
This study investigated the optimum polyphenol extraction conditions for two Nigerian green leafy vegetables, Vernonia amygdalina (VA) and Gongronema latifolium (GL) that are widely used for food and medicinal purposes. Seven different solvents were used to extract the total phenolic contents of the leaves; 100% acetone, 80% acetone, 50% acetone, 100% ethanol, 70% ethanol, 100% methanol and 70% methanol and their total phenolic contents were determined. The results showed that the 80% acetone was significantly (p<0.05) the most effective for polyphenol extraction from the leaves and generally the acetone-containing solvents were more effective than alcohol-containing solvents. The 80% acetone extract was fractionated on a silicic acid-packed column to give two main fractions: acetone elute...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional pe...
A Real-Time Neutron Radiography (RTNR) system is developed to determine two-phase flow parameters for a vertical co-current two-phase flow channel with a hexagonal finned bundle. Image processing techniques are applied to visualize the two-phase flow, and procedures for measuring flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution for this complex geometry are discussed. The results show that the experimental flow regime map agrees well with an existing flow regime model for a hexagonal fined bundle. The hexagonal finned bundle is observed to significantly affect the void fraction, void migration, and void fluctuation along the axial flow channel.
A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C18 silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always sh...
System identification refers to estimation of process parameters and is a necessity in control theory. Physical systems usually have varying parameters. For such processes, accurate identification is particularly important. Online identification schemes are also needed for designing adaptive controllers. Real processes are usually of fractional order as opposed to the ideal integral order models. In this paper, we propose a simple and elegant scheme of estimating the parameters for such a fractional order process. A population of process models is generated and updated by particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. Results show that the proposed scheme offers a high degree of accuracy even when the observations are corrupted to a significant degree. Additional schemes to improve the accuracy still further are also proposed and analyzed.
The study presented in this thesis is a contribution about the analysis of failures modes of electrolytic capacitors and thyristors. The studied components are main elements of the protection system of the superconductive magnets of the LHC. The study of the ageing of the electrolytic capacitors has shown that their reliability is strongly related to their technological characteristic. Evolution of their principal indicator of ageing (ESR) can be modeled according to different laws chosen according to their running mode. It appears that the prediction of failure of these components other than that due to wear can be only statistical taking into account the many causes of failure involving various modes of failure. In order to be able to evaluate influence of the ageing of the electrolytic capacitors on a system, simple models taking into account this parameters as well as the effective temperature of the component are proposed. An acceptable precision taking into account the simplicity ...
Understanding the structure of the nucleon is a fundamental question in subatomic physics, and it has been under intensive investigation for the last several years. Modern research focuses in particular on the spin structure of the nucleon. Experimental and theoretical investigations worldwide over the last few decades have established that, contrary to nave quark model expectations, quarks carry only about 30% of the totd spin of the proton. The origin of the remaining spin is the key question in current hadronic physics and also the major driving forces for the current and future experiments, such as RHIC and CEBAF in US, JPARC in Japan, COMPASS at CERN in Europe, FAIR at GSI in Germany. Among these studies, the transverse-spin physics develops actively and rapidly in the last few years. Recent studies reveal that transverse-spin physics is closely related to many fundamental properties of the QCD dynamics such as the factorization, the non-trivial universality ...
The authors report the observation of B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillations from a time-dependent measurement of the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillation frequency {Delta}m{sub s}. Using a data sample of 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron, they find signals of 5600 fully reconstructed hadronic B{sub s} decays, 3100 partially reconstructed hadronic B{sub s} decays, and 61,500 partially reconstructed semileptonic B{sub s} decays. They measure the probability as a function of proper decay time that the B{sub s} decays with the same, or opposite, flavor as the flavor at production, and they find a signal for B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillations. The probability that random fluctuations could produce a comparable signal is 8 x 10{sup -8}, which exceeds 5{sigma} significance. They measure {Delta}m{sub s} = 17.77 {+-} ...
The status of Monte Carlo system for the simulation of Bremsstrahlung in arbitrary decays and for the decay itself of #tau# -lepton is reviewed. During the last #tau# -lepton conference in 2010 several developments of the last two years have been presented: (i) For the TAUOLA Monte Carlo generator of #tau# -lepton decays, automated and simultaneous use of many versions of form-factors for the calculation of optional weights for fits was developed and checked to work in Belle and BaBar software environment. On-going work on alternative parameterizations of hadronic decays is presented too. (ii) The TAUOLA universal interface based on HepMC (the C++ event record) is now public. A similar interface for PHOTOS is now also public. (iii) Extension of PHOTOS Monte Carlo for QED Bremsstrahlung in decays featuring kernels based on complete first order matrix element are gradually becoming widely available thanks to properties of the new, HepMC based interface. (iv) Tests of ...
We investigate the possibility of kaon condensation in the dense interior of neutron stars through the s-wave interaction of kaons with nucleons. We include nucleon-nucleon interactions by using simple parametrizations of realistic forces, and include electrons and muons in #beta#-equilibrium. The equation of state above the condensate threshold is derived in the mean field approximation. The conditions under which kaon condensed cores undergo a transition to quark matter containing strange quarks are also established.The critical density for kaon condensation lies in the range (2.3-5.0)#rho#_0, where #rho#_0=0.16 fm"-"3 is the equilibrium density of nuclear matter. The critical density depends largely on the value of the strangeness content of the proton, the size of which is controversial. For too large a value of the strangeness content, matter with a kaon condensate is not sufficiently stiff to support the lower limit of 1.44 M_o_e_d_o_t for a neutron star. Kaon condensation ...
We discuss various reactions at future e"+e"- and #gamma##gamma# colliders involving real (beamstrahlung or backscattered laser) or quasi-real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large transverse momentum p_T is described in some detail; we give distributions for the rapidity and p_T of the jets as well as the di-jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties that arise from the at present rather poor knowledge of the parton content of the photon. We also present results for 'mono-jet' production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production of W and Z bosons. Where appropriate, the two-photon processes are compared with annihilation reactions leading to similar final states. We also argue that the behaviour of the total inelastic #gamma##gamma# ...
Statistical design of experiments is widely used among scientists and engineers to understand influential factors in a laboratory or manufacturing process. One of the underlying principles of...Full Text Available
An interfacial shear stress equation in the dispersed-annular two-phase flow regime has been developed, which is based on a three-fluid model consisting of a liquid film on a rod, vapor and entrained liquid associated with a vapor flow. It is an extension of J.G.M. Andersen's procedure that provides a two-fluid interfacial shear stress equation using the drift flux parameters C{sub 0} and V{sub gj}. This interfacial shear stress equation can take into account a phase and velocity distribution through an equivalence between the drift flux parameters and the interfacial shear stress. Using the three-fluid subchannel analysis code TEMPO with the three-fluid interfacial shear stress model the capability of a three-fluid calculation using the drift flux parameters C{sub 0} and V{sub gj} that reproduce a measured void fraction is demonstrated. A comparison was made with advanced X-ray computed tomography (CT) void fraction data within a 4x4 ...
This research aims at elucidating thermal hydraulic phenomena by carrying out their visualization and measurement which are difficult by conventional method, utilizing the excellent properties of real time neutron radiography and showing the usefulness of neutron radiography. The experiments were carried out on the visualization and measurement of liquid metal flow and mixed phase flow and the visualization and diagnosis of mixed phase flow equipment. As the achievement in this fiscal year, the image-processing method for visualizing quantitatively the distribution of void fraction in gas-liquid two-phase flow has been devised, therefore, its method and results are reported. For the analysis of multi-dimensional two-phase flow, in order to prepare the model and determine the constitution equation, the data on the multi-dimensional distribution of void fraction are required. Void fraction is defined. The method of image ...
Subcellular-fractionation techniques were used to characterize the endocytic pathway followed by ricin in rat liver in vivo and tentatively identify the site(s) at which the ricin interchain disulphide...Full Text Available
Particle swarm optimization (PSO) is extensively used for real parameter optimization in diverse fields of study. This paper describes an application of PSO to the problem of designing a fractional-order proportional-integral-derivative (FOPID) controller whose parameters comprise proportionality constant, integral constant, derivative constant, integral order (lambda) and derivative order (delta). The presence of five optimizable parameters makes the task of designing a FOPID controller more challenging than conventional PID controller design. Our design method focuses on minimizing the Integral Time Absolute Error (ITAE) criterion. The digital realization of the deigned system utilizes the Tustin operator-based continued fraction expansion scheme. We carry out a simulation that illustrates the effectiveness of the proposed approach especially for realizing fractional-order plants. This paper also attempts to study the ...
We study the redshift evolution of galaxy pair fractions and merger rates for different types of galaxies using kinematic pairs selected from the DEEP2 Redshift Survey. Parameterizing the evolution of the pair fraction as (1+z)^{m}, we find that the companion rate increases mildly with redshift with m = 0.41+-0.20 for all galaxies with -21 < M_B^{e} < -19. Blue galaxies show slightly faster evolution in the blue companion rate with m = 1.27+-0.35 while red galaxies have had fewer red companions in the past as evidenced by the negative slope m = -0.92+-0.59. We find that at low redshift the pair fraction within the red sequence exceeds that of the blue cloud, indicating a higher merger probability among red galaxies compared to that among the blue galaxies. With further assumptions on the merger time scale and the fraction of pairs that will merge, the galaxy major merger rates for 0.1 < z ...
Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI...Full Text Available
BackgroundCaesarean section is one of the most commonly performed operations on women throughout the world. Rates have increased in recent years – about 20–25% in...Full Text Available
BackgroundMicrovascular injury plays a key role in normal tissue radiation responses. Statins, in addition to their lipid-lowering effects, have vasculoprotective...Full Text Available
The separation of bitumens (B) and natural asphalts using a dialysis (D) method is studied. A moderately vulcanized latex of natural rubber, which was subjected to extraction by cold n-hexane prior to use, was used as the material of the membrane for dialysis. With dialysis of bitumen samples dispersed in a small quantity of n-alkane in a Soxhlet apparatus three fractions were acquired: a dialyzate, an undialyzable fraction and asphaltenes (the residue). N-pentane, n-hexane and n-heptane were used as the solvents for dialysis. Samples of oxidized road bitumen, grade AOSI 85/25, bitumens from the process of propane deasphaltization, natural asphalts from Trinidad and Albania and A80 grade bitumens from the oil distillation process were isolated using the dialysis method. The reproducability of the output of the fractions with varying suspensions and productivity of the dialysis, the dependence of the output on the length of ...
Proteins in the ALA-D (delta-aminolaevulinic acid dehydratase) fraction from gel filtration of erythrocyte supernatant (ES) have the highest affinity for lead among erythrocyte constituents in vivo...Full Text Available
OBJECTIVE: To evaluate prospectively the efficacy of a single fraction of high-dose radiotherapy in patients with Kaposi's sarcoma. PATIENTS: Between 1994 and 2004, 47 patients with Kaposi's sarcoma...Full Text Available
Two xyloglucan fractions have been isolated from the cotyledons of resting white-mustard seeds, the first by extraction with hot EDTA, and the second by subsequent extraction with alkali or lithium...Full Text Available
The plasma protein binding of phenytoin was investigated in 100 epileptic patients, using equilibrium dialysis at 37 degrees C. The unbound fractions of phenytoin in plasma formed a skewed distribution,...Full Text Available
The purpose of the present work was to study the pharmacokinetics and the protein binding (free fraction of the drug) of ceftriaxone (CTX) during pregnancy. Nine pregnant women (ages, 20 to 34 years)...Full Text Available
An enriched glucan synthase fraction was obtained from red beet root microsomes by sequential extraction with the detergents 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate and digitonin....Full Text Available
Theoretical investigations on the phase change materials (PCMs) used as the heat storage media for box-type solar cookers have been conducted in this study. The selected PCMs are magnesium nitrate hexahydrate, stearic acid, acetamide, acetanilide and erythritol. For a two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Different materials such as glass, stainless steel, tin, aluminum mixed, aluminum and copper are used as the heat exchanger container materials in the numerical calculations. The large value of thermal conductivity of heat exchanger container material did not make a significant contribution on the melt fraction except for at very low thermal conductivities. Based on the theoretical results, stearic acid and acetamide are found to be good compatibility with latent heat storage system. It is also found that the initial temperature of PCM does not ...
Transposable elements (TEs) comprise a large fraction of mammalian genomes. A number of these elements are actively jumping in our genomes today. As a consequence, these insertions provide a source...Full Text Available
The fraction of a given area of ground that is covered by hail can be determined by using an airborne infrared thermometer. If the ambient ground temperature and the hail-covered ground temperature are measured with the same thermometer, and the surface o...
Despite the availability of dozens of animal genome sequences, two key questions remain unanswered: First, what fraction of any species' genome confers biological function, and second, are apparent...Full Text Available
Basal segments taken from Old Home and Bartlett pear hardwood cuttings collected at intervals during the rooting period in September were extracted with ethanol and fractionated by paper chromatography...Full Text Available
BackgroundA large fraction of the human genome is attributable to L1 retrotransposon sequences. Not only do L1s themselves make up a significant portion of the genome, but L1-encoded...Full Text Available
The various steps of gas treatment in the Sasol II coal liquefaction plant are discussed: CO/sub 2/ removal, separation of the hydrocarbon fractions and the recirculated hydrogen by low-temperature decomposition, production of pure hydrogen by alternating pressure absorption.
The functional and thermodynamic characteristics of the ubiquinolcytochrome (Cyt) c oxidoreductase in a Cyt b/c1-enriched fraction (defined...Full Text Available
Background:There is a need for simple imaging parameters capable of predicting therapeutic outcome.Methods:This retrospective study analysed 50 patients...Full Text Available
In recent years, Salmonella enteritidis has become an increasingly important public health problem in Italy. In some parts of the country, the fraction of total human salmonella isolates...Full Text Available
The effect of organic (fulvic and humic acids) and inorganic fractions of soil on the sorption and extractability of /sup 239/Pu(IV) as a function of pH was determined by using an equilibrium batch technique. The results indicated that Pu(IV) is strongly sorbed on the inorganic fraction of the soil under soil pH conditions normally encountered in natural environments. Plutonium appeared to form stable complexes or chelates with fulvic and humic acids in the pH range studied (1.3 to 11.7). In mixtures of pure fulvic or humic acids with soil inorganic fractions, extractability of Pu was substantially influenced by organic-inorganic interaction. The influence of the inorganic fractions was most evident in the lower pH ranges, whereas that of the organic materials was most evident in the higher pH ranges, generally above pH 6. Some implications of the results on plutonium movement in soils were discussed.
High-density lipoproteins (HDL) were examined as potential carriers of small peptides in plasma. HDL purified by density gradient centrifugation was delipidated and fractionated by size-exclusion...Full Text Available
A new process for the hydrogenation of coal in the presence of wide-cut coal tar was proposed; it involves cavitation treatment, mixing with catalytic additives, and heating the resulting mixture at an elevated pressure in an atmosphere of hydrogen. The yields of hydrocarbon fractions to 300?C and gas condensate were evaluated.
Quantitative metallography is often used to confirm the proper processing of aerospace metallic materials. A microstructural feature of great importance for titanium alloys processed in the alpha-beta phase field is the volume fraction of primary alpha. S...
BackgroundEchocardiography is widely used in the management of patients with cardiogenic shock (CS). Left ventricular ejection fraction (EF) has been shown to be an independent predictor...Full Text Available
Feb 15, 2008 ... hydrological properties (e.g., hydrometeor budgets, cloud ice/water, transports ... cloud fraction, mass and particle size. In combination, these .... anomaly in the LS is not simply due isentropic movement of water vapor relative ...
The monoterpene fraction of the lemon-scented sweet basil (Ocimum basilicum) cv Sweet Dani consists mostly of citral (a mixture of geranial and neral), with lower levels of geraniol...Full Text Available
The German state of Sachsen is a synonym for brown coal production. The elections to the state parliament will decide the future of this echnology and of climate protection strategies like renewable energy sources. A renewables fraction of 82 percent of renewables-derived electric power may be possible by 2020. (orig.)
The report gives results of an examination, including mutagenic screening, of the chemical composition of residual fuel oils and their column chromatography pre-fractions. A degree of correlation between composition and mutagenicity has been achieved. Radionuclide data has been o...
Based on the assumption that an accelerated proliferation process prevails in tumour cell residues after surgery, the possibility that treatment acceleration would offer a therapeutic advantage in postoperative...Full Text Available
In the past decade in vitro tests have been developed that represent a range of anatomic structure from perfused whole organs to subcellular fractions. To assess the use of in vitro tests for toxicity...Full Text Available
The pattern of biodegradation and the chemical changes occurring in the macromolecular fraction of domestic sludge during autothermal thermophilic aerobic digestion (ATAD) was monitored and characterised...Full Text Available
Drell-Yan pair production is investigated. We reexamine a model where the quark momentum fraction is defined as the ratio of the corresponding light-cone components of the quark and parent nucleon in a naive parton-model approach. It is shown that the results differ from the standard parton model. This is due to unphysical solutions for the momentum fractions within the naive approach which are not present in the standard parton model. In a calculation employing full quark kinematics, i.e., including primordial quark transverse momentum, these solutions also appear. A prescription is given to handle these solutions in order to avoid incorrect results. The impact of these solutions in the full kinematical approach is demonstrated and compared to the modified result.
Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.
Dietary supplements of about 5 g/kg of a number of amino acids increased tissue lead concentrations in newly weaned rats but decreased them in older rats. The retention of both oral and intraperitoneal lead was affected. The uptake of "2"0"3Pb by tissues was reduced when methionine was given in the diet over a period of 5 weeks or when it or ethionine was given by mouth 24 h before the activity was measured. In the liver the fraction of the total activity found in the nuclei and mitochondria was increased by methionine, but in the kidney only the fraction found in nuclei was increased.
Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10{sup 6}n/cm{sup 2}-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,{integral}dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and CANDU-type nuclear fuel flow channels are investigated. ...
Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10"6n/cm"2-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,#integral#dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and CANDU-type nuclear fuel flow channels are investigated. Measurements ...
A preliminary investigation was completed on the characterization and decontamination of coral samples from Johnston Island. These samples were found to contain individual particles (2 to 0.25 mm) of contaminated coral as well as a piece of contaminated magnetic metal. They ranged in activity from about 70 to 811 nCi Am-241. The decontamination methods investigated were froth flotation, ferrite treatment, attrition scrubbing, ultrasonic treatment and dry sieving. Dry sieving, the more effective technique, separated about 42 wt % of the coral into a decontaminated fraction. This fraction (>4 mm) contained about 0.5% of the total activity. 7 refs., 3 tabs.
The identification and characterization of carbonaceous materials (CMs) that control hydrophobic organic chemical (HOC) sorption is essential to predict the fate and transport of HOCs in soils and sediments. The objectives of this paper are to determine the types of CMs that control HOC sorption in the oxidized and reduced zones of a glacially deposited groundwater sediment in central Illinois, with a special emphasis on the roles of kerogen and black carbon. After collection, the sediments were treated to obtain fractions of the sediment samples enriched in different types of CMs (e.g., humic acid, kerogen, black carbon), and selected fractions were subject to quantitative petrographic analysis. The original sediments and their enrichment fractions were evaluated for their ability to sorb trichloroethene (TCE), a common groundwater pollutant. Isotherm results and mass fractions of CM enrichments were ...
Adjuvant-induced arthritis in rats is a chronic inflammatory disease, widely as an animal model for rheumatoid arthritis. In our study the effect of various fractions of dialyzable leukocyte extract (DLE): DLE I-molecular weight below 10 kDa (commercial preparation), DLE II-molecular weight below 5 kDa (suppressor fraction), DLE III-molecular weight 5-10 kDa on rat adjuvant-induced arthritis was studied. The adjuvant arthritic (AA) rats were treated with DLE fractions i.p. in solutions containing an active substance isolated from 12.5 x 10{sup 6} and 6.25 x 10{sup 6} leukocytes from day 1 (adjuvant injected) through day 18, every second day (total 9 times). Various markers in inflammation, immune function and joint destruction were evaluated: hind paw volume, serum hyaluronic acid, serum albumin and biopterin in urine. All these markers showed a significant improvement after using fraction DLE II in ...
The importance of cellular dosimetry in both diagnostic and therapeutic nuclear medicine is becoming increasingly recognized. Experimental range-energy relations for electrons and alpha particles, along with derived geometric reduction factors, are used to calculate cellular absorbed fractions for these radiations. The resulting absorbed fractions are employed to calculate cellular S-values for several radionuclides. Cellular absorbed fractions for monoenergetic electron sources with energies ranging from 0.1 keV to 1 MeV, distributed uniformly in the source region, are calculated for several target {l_arrow} source combinations including cell{l_arrow}cell, cell{l_arrow}cell surface, nucleus{l_arrow}nucleus, nucleus {l_arrow}cytoplasm and nucleus {l_arrow}cell surface. Similar data are also provided for monoenergetic alpha particle sources with energies ranging from 3 to 10 MeV. S-values are also conveniently tabulated for ...
Medicinal plants play a major role in the life of Turkish people and of late medicinal plant usage has increased in many countries. Green plants in general contain mutagenic and carcinogenic substances, but there is little information about the biological activities of herbal medicine. In the present study, therefore, various Turkish medicinal herbs were investigated for their genotoxic potential in the Salmonella typhimurium microsomal activation assay and the alkaline single cell gel electrophoresis (COMET) assay. Extracts from these medicinal herbs and some fractions of these extracts were examined. The species investigated were Arctium minus, Ecballium elatterium, Momordica charantia, Plantago major, Urtica dioica, Viscum album, Salvia triloba, Euphorbia rigida, Stachys lavandulifolia, Acteoside, Abies nordmannia. They are used for various immune disorders and are applied either topically or taken orally as a herbal tea. Of the 19 samples of the extracts and ...
We report de Haas--van Alphen measurements of the Fermi surface of lutetium at temperatures down to 0.3 K and in fields up to 150 kG in the (1010) and (1120) planes. Lutetium, having a filled 4f shell, serves as a nonmagnetic prototype of the structurally similar (hcp), trivalent, heavy rare-earth elements from Gd to Tm. The fact that no complete frequency branches were observed indicates that there are no closed pieces of the Fermi surface. We observed all but one orbit predicted by relativistic augmented-plane-wave calculations of Keeton and Loucks and by recent spin-orbit--linearized-augmented-plane-wave calculations of Tibbetts and Harmon. The data support a geometry similar to that of yttrium, and in good qualitative agreement with energy-band theory.
A new class of (not necessarily bounded) operators related to (mainly infinite) directed trees is introduced and investigated. Operators in question are to be considered as a generalization of classical weighted shifts, on the one hand, and of weighted adjacency operators, on the other; they are called weighted shifts on directed trees. The basic properties of such operators, including closedness, adjoints, polar decomposition and moduli are studied. Circularity and the Fredholmness of weighted shifts on directed trees are discussed. The relationships between domains of a weighted shift on a directed tree and its adjoint are described. Hyponormality, cohyponormality, subnormality and complete hyperexpansivity of such operators are entirely characterized in terms of their weights. Related questions that arose during the study of the topic are solved as well. Particular trees with one branching vertex are intensively studied mostly in the context of subnormality and ...
Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilised e.g. in agglomeration processes (sintering, pelletising or briquetting) and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverised coal (PC) has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.
Objective: To investigate the inserting technique of biliary double stents in treating hilar cholangiocarcinoma. Methods: 6 patients with hilar cholangiocarcinoma (Bismuth IV) were treated by percutaneous transhepatic insertion of biliary stents. Double stents were inserted in each patient. Different inserting methods were adopted according to the branch angles formed by left and right hepatic ducts. Results: The jaundice of all patients alleviated or disappeared obviously after stent implantation. The average difference between post-and pre-operation in the serum total bilirubin level was (104 #+-# 29) #mu#mol/L (P<0.01). Stent obstruction was found in 2 cases after 4 and 6 months respectively. Conclusion: Double stents implantation is effective for the treatment of hilar cholangiocarcinoma. Beware of the angulation between main hepatic duct and adopting different inserting methods. (authors)
In the littlest Higgs model with T-parity (LHT), the mirror quarks have flavor structures and will contribute to the top quark flavor changing neutral current. In this work, we perform an extensive investigation of the top quark rare three-body decays $t\\rightarrow cVV (V=\\gamma,Z,g)$ and $t\\rightarrow cf\\bar{f} (f=b,\\tau,\\mu,e)$ at one-loop level. Our results show that the branching ratios of $t\\rightarrow cgg$ and $t\\rightarrow cb\\bar{b}$ could reach $\\mathcal {O}(10^{-3})$ in the favorite parameter space of the littlest Higgs model with T-parity, which implies that these decays may be detectable at the LHC or ILC, while for the other decays, their rates are too small to be observable at the present or future colliders.
The situation of natural gas in the Federal Republic of Germany is described, with particular emphasis on the advantages and consequences of natural gas supply. The brochure discusses the role of natural gas on the energy market, the reliability of natural gas supply, the environmental impacts, the energy-saving effect of natural gas, natural gas prices, the competitive strength of the German gas industry, and the long-term reliability of natural gas supply. (orig.) [German] Die Situation des Erdgases in der Bundesrepublik Deutschland wird beschrieben, wobei die wichtigsten Vorteile und Auswirkungen der Erdgasversorgung besonders hervorgehoben werden. Es geht um die Stellung des Erdgases im Energiemarkt, die Sicherheit der Energieversorgung, Umweltschutz, Energieeinsparung durch Erdgaseinsatz, Erdgaspreise, Leistungsfaehigkeit der deutschen Gaswirtschaft und um die langfristig gesicherte Erdgasversorgung. (orig.)
The economic development of eastern Europe was associated during the last 15 years with the following average annual increases in energy consumption: Approximately 1% in the sectors industry, building and transport, almost 7% in the farming sector, approximately 3% in households, and nearly 4% in the municipal sector. This trend will not continue. As the economic system shifts from centrally planned to free economy and as the previously secluded economy is forced to face world market conditions as well as changed pars of exchange and conditions of payment, it not only experiences a transitory, sharp dip of economic growth in general but, in particular, drastic structural changes. - While there is to be expected, on the whole a slump in national economic growth, in tradiational branches of industry (e.g., metallurgy, the chemicals and textile industry) as well as in farming, such sectors as the service industry and small trade are expanding. (orig./UA).
Eu"3"+ and Tb"3"+ complexes with novel branched calix[4]arene ligands incorporating 2,2' -bipyridine subunits functionalized in the 6- or 5,5'-positions have been synthesized and their photophysical properties investigated. High luminescence intensity was obtained for the Eu"3"+ complex of the calix[4]arene ligand carrying four 5,5' -substituted- 2,2' -bipyridines, which has high molar extinction coefficients (#epsilon#_m_a_x 39 600 M"-"1 cm"-"1) and a high luminescence quantum yield (15%). (authors). 12 refs., 2 figs., 1 tab.
The energy level schemes of /sup 192/Os and /sup 192/Pt have been established on the basis of ..gamma..-..gamma.. coincidence studies using a dual parameter data collection system. Ge(Li) detectors were employed to study the gamma spectra produced in the E.C. and ..beta../sup -/ decays of /sup 192/Ir to /sup 192/Os and /sup 192/Pt, respectively. Thirteen new transitions and three new levels at 1146.95, 1237.35 and 1913.76 keV are suggested. Relative intensities from singles measurements, branching ratios, ..cap alpha..(K) and log ft values were calculated and multipolarities, spins and parities deduced. Comparisons are made with predictions of the Interacting Boson Model calculated on the basis of an O(6) to SU(3) transition.
The energy level schemes of "1"9"2Os and "1"9"2Pt have been established on the basis of #gamma#-#gamma# coincidence studies using a dual parameter data collection system. Ge(Li) detectors were employed to study the gamma spectra produced in the E.C. and #beta#"- decays of "1"9"2Ir to "1"9"2Os and "1"9"2Pt, respectively. Thirteen new transitions and three new levels at 1,146.95, 1,237.35 and 1,913.76 keV are suggested. Relative intensities from singles measurements, branching ratios, #alpha#(K) and log ft values were calculated and multipolarities, spins and parities deduced. Comparisons are made with predictions of the Interacting Boson Model calculated on the basis of an O(6) to SU(3) transition. (orig.).
The analysis of images (of obtained in various ranges of the lengths of waves) of luminous objects in the Universe by means of a method of multilevel dynamic contrasting led author to the conclusions: a) the structures of all observable galaxies represents a complicated constructions which have the tendency to self-similarity and made of separate (basic) blocks, which are a coaxially tubular structures and a cartwheel-like structures; b) the majority of observable objects in the Universe are luminous butt-ends of almost invisible (of almost completely transparent) of filamentary formations which structures are seen only near to their luminous butt-ends; c) the result of analysis of images of cosmic objects show the structure of many pairs of cooperating galaxies point to opportunity of their formation at butt-ends generated in a place of break of the similar filament; d) the interacting galaxies (M 81 and M 82) show they are butt-ends of sawed off of two branches ...
Million-atom molecular-dynamics (MD) simulations are performed to study the structure, mechanical properties, and dynamic fracture in nanophase Si{sub 3}N{sub 4}. The authors find that intercluster regions are highly disordered: 50% of Si atoms in intercluster regions are three-fold coordinated. Elastic moduli of nanophase Si{sub 3}N{sub 4} as a function of grain size and porosity are well described by a multiphase model for heterogeneous materials. The study of fracture in the nanophase Si{sub 3}N{sub 4} reveals that the system can sustain an order-of-magnitude larger external load than crystalline Si{sub 3}N{sub 4}. This is due to branching and pinning of the crack front by nanoscale microstructures.
Summary: The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR res...
Deltombe T, Gustin T. Selective tibial neurotomy in the treatment of spastic equinovarus foot in hemiplegic patients: a 2-year longitudinal follow-up of 30 cases. Objective To assess the long-term efficacy of selective tibial neurotomy in the treatment of spastic equinovarus foot in hemiplegic patients. Design Intervention study (before-after trial) with an observational design and 2-year follow-up. Setting Spasticity group in a university hospital. Participants Hemiplegic patients (N=30) with spastic equinovarus foot. Intervention A selective neurotomy was performed at the level of the motor nerve branches of the tibial nerve. Main Outcome Measures Spasticity (Ashworth scale), muscle strength (Medical Research Council scale), passive ankle dorsiflexion, gait parameters (6 min walking test...
We have investigated via SQUID magnetometry and polarised neutron reflectivity the exchange-bias effect in CoO/Co sputtered multilayers. In particular, we studied the magnetisation reversal and the time relaxation of the exchange-bias field close to the coercive field H{sub c1}. Neutron intensities of all four cross sections (I++, I+-, I-+, I-) were recorded at the position of the first multilayer Bragg peak while scanning the magnetic field. From such scans we infer that the magnetisation reversal for the ascending as well as for the descending branch of the magnetic hysteresis occurs not by in-plane rotation but through domain-wall movements. The exchange-bias field, H{sub EB}, is strongly affected by thermal fluctuations. H{sub EB} decreases, following an exponential decay function with a half-life time of about 580 s at T=240 K. (orig.)
This book presents the proceedings of a conference dedicated to the design and operation of pipework in all its aspects, involving both metallic and non-metallic materials. Topics considered include a study of single mitre pipe bends using the finite element method; tests to failure of GRP pipe bends under in-plane flexural loading; finite element stress analysis of an equal diameter branch pipe intersection subjected to internal pressure and in-plane moment loadings; finite element stress analysis of extruded outlet tee junctions; design of pipework on the British PWR; a review of advanced remanent life methods for pipes operating in the creep range; pipe whip analysis and design; damping values for piping systems; pipework snubbers based on electro-rheological fluids; and the seismic design of piping systems in the flexible range.
Abstract Papillary epithelial fragments (PEFs) are a rarely described architectural feature in cervicovaginal (Pap) smears. Morphologically, PEFs often consist of small, finely branching glandular tissue fragments with varying cytomorphology. This study identified 21 Pap smears (1978-2009) containing PEFs to determine the clinicopathologic significance of such findings. Patients ranged in age from 36 to 81 years (mean, 54 years). The Pap smear diagnoses consisted of 48% overt malignant neoplasms, 24% atypical fragments, and 28% benign entities. The papillary fragments featured a range of cytomorphologies consisting of benign features, mild to marked atypia, and overt malignancy. PEFs were more commonly found (57%) in specimens from patients with significant pathologic outcomes. Hence, the ...
This paper discusses organizational models of planning technology development in coal mining. The following 4 planning systems are analyzed: all-union national system coordinated by the Ministry of Coal Mining of the USSR, all-union associations of coal mine associations (in the Ukrainian SSR the plan is developed by the Ministry of Coal Industry of the Republic), associations of coal mines, coal mines or groups of coal mines. Methods for developing programs for technology development at 4 levels are reviewed. The following planning periods are used: 10 years or more (from 1980 to 1990), a 5 year period and a 1 year period. System for technology development in the Soviet coal industry from 1981 to 1985 is evaluated: research and development programs (20 comprehensive state programs, 36 branch programs). (In Russian)
Silica glasses containing Pr"3"+ with and without CdS nanoparticles were prepared by sol-gel technique. The influence of CdS nanoparticles on Pr"3"+ doped glass was studied by absorption, photoluminescence and up-conversion. From the measured intensities of various absorption bands of these glasses, the Judd-Ofelt parameters ?_2, ?_4 and ?_6 have been evaluated. The radiative transition probability (A), radiative lifetime (?_R), branching ratio (?_R) and integrated emission cross-section (?_P) were calculated from excited states of "3P_1 and "3P_0 levels. The up-conversion emissions were found in the green, orange and red regions under 800 nm excitation with peaks 559, 612 and 688 nm respectively. On excitation with 370 nm also leads to similar green, orange and red regions.
Synergism has been observed during inhibiting initiated oxidation of styrene or tetralin by organic phosphites in the presence of complex compounds of some transition metals. The results are given of non-additive intensification of antioxidative activity of triphenylphosphite (TPP) and tri-(4-methyl-6-tert.-- butyl)-phenyl-phosphite (TMBP) in the process of initiated oxidation of styrene or tetralin with addition of acetylacetonates of cobalt and vanadyl. During styrene oxidation, inhibition of the reaction with chelate complex of vanadyl is weakened considerably when phosphite is added into the reaction system. During tetralin oxidation, postcatalytic (or branched) oxidation is observed only for large concentration of vanadyl complex. Addition of TPP to above complex sharply increases the induction period. When the induction period is completed, oxidation of tetralin follows the mechanism of usual, i.e. initiated, reaction.
Decays of $\\chi_{c0,2}\\ar\\ww$ are observed for the first time using a sample of $14.0\\times 10^6$ $\\psi(2S)$ events collected with the BESII detector. The branching ratios are determined to be ${\\cal B}(\\chi_{c0}\\ar \\ww)=(2.29\\pm 0.58\\pm 0.41)\\times 10^{-3}$ and ${\\cal B}(\\chi_{c2}\\ar\\ww)=(1.77\\pm 0.47\\pm 0.36)\\times 10^{-3}$, where the first errors are statistical and the second systematic. The significances of the two signals are $4.4\\sigma$ and $4.7\\sigma$, respectively.
A more complete level scheme is presented here for the decay of [sup 187]Pt, incorporating many new lines and levels up to 2.4 MeV. Emphasis has been placed on the extraction of multipole mixing ratios from nuclear orientation data. Analysis of that data, however, required a more complete understanding of the level structure (including, in particular, branching ratios, conversion coefficients, and level feedings), prompting the collection of new spectroscopy data. The low-lying, positive-parity levels are described in terms of (odd-proton) single-particle Nilsson states coupled to a triaxial core. Multipole mixing ratios are compared to those calculated in the Particle-Plus-Triaxial-Rotor Model. (orig.).
A more complete level scheme is presented here for the decay of "1"8"7Pt, incorporating many new lines and levels up to 2.4 MeV. Emphasis has been placed on the extraction of multipole mixing ratios from nuclear orientation data. Analysis of that data, however, required a more complete understanding of the level structure (including, in particular, branching ratios, conversion coefficients, and level feedings), prompting the collection of new spectroscopy data. The low-lying, positive-parity levels are described in terms of (odd-proton) single-particle Nilsson states coupled to a triaxial core. Multipole mixing ratios are compared to those calculated in the Particle-Plus-Triaxial-Rotor Model. (orig.).
The history of the North German Mission Society (established 1836 in Hamburg) and its activity on the West African coast (from 1847 onwards among the Ewe, in what is now Ghana and Togo where it was and still is known as the 'Bremen Mission') mirrors neatly the various phases of the idea of 'mission': its composite motivation (Enlightenment, humanism and Pietism); the rejection of a narrow denominationalism (though the management of the mission was from 1850 onwards in the hands of the society's Bremen branch which belonged to the Reformed tradition); the entanglement of mission and overseas trade; the ambivalent attitude towards imperialism; the shaping of the missionary process as a profoundly educational one; the growing independence of the African church when the German missionaries wer...
We show how the formulation of the matrix models as conformal field theories on a Riemann surfaces can be used to compute the genus expansion of the observables. Here we consider the simplest example of the Hermitian matrix model, where the classical solution is described by a hyperelliptic Riemann surface. To each branch point of the Riemann surface we associate an operator which represents a twist field dressed by the modes of the twisted boson. The partition function of the matrix model is computed as a correlation function of such dressed twist fields. The perturbative construction of the dressing operators yields a set of Feynman rules for the genus expansion, which involve vertices, propagators and tadpoles. The vertices are universal, the propagators and the tadpoles depend on the Riemann surface. As a demonstration we evaluate the genus-two free energy using the Feynman rules.
17 patients with chronic aortic dissection were examined by MRI. In 12 patients, comparison between gradient echo sequences and SE sequences was possible. Gradient echo sequences, unlike SE sequences, permitted evaluation of flow in the true and false lumen, reliable differentiation between thrombus and flowing blood and clear delination of the intimal flap. An additional comparison between transoesophageal ultrasound and MRT in 15 patients showed significant advantages in favour of MRI. In three patients MRI was able to detect more proximal origins of the dissection. Moreover, MRI allowed evaluation of the major aortic branches and their relation to the dissection; this was not possible with ultrasound. MRI plays an important role in the follow-up of chronic aortic dissections. (orig.).
We interpret N=2 superconformal field theories (SCFTs) formulated by Kazama and Suzuki via Goddard-Kent-Olive (GKO) construction from a viewpoint of the Lie algebra cohomology theory for the affine Lie algebra. We determine the cohomology group completely in terms of a certain subset of the affine Weyl group. We find that this subset describing the cohomology group can be obtained from its classical counterpart by the action of the Dynkin diagram automorphisms. Some algebra automorphisms of the N=2 superconformal algebra are also formulated. Utilizing the algebra automorphisms, we study the field identification problem for the branching coefficient modules in the GKO-construction. Also the structure of the Poincare polynomial defined for each N=2 theory is revealed. (orig.).
A 340-watt CO_2 laser is being used to generate PuO_2-UO_2 condensation aerosol from the surface of a Liquid Metal Fast Breeder Reactor (LMFBR) fuel pellet. A wide range of concentrations is achieved by varying the laser power, pulse width, and/or pulse period. The resulting aerosol is composed of branch chain-like aggregates, with the primary particle size ranging between 0.005 and 0.15 #mu#m. X-ray diffraction analyses show that these aerosols condense into a face-centered cubic crystal structure. The activity mean aerodynamic diameter (AMAD), for most power levels, is approximately 0.85 #mu#m with a geometric standard deviation of 1.5.
The penumbra of the profile function describing the nuclear collisions of relativistic heavy ions is related to the cross section for their producing a specific target-nucleus #gamma#-ray, sigmasub(#gamma#). The analysis assumes that the diffuse-edge diffraction model suffices to calculate the inelastic cross sections to the particle-stable states of the target nucleus. When the deformation lengths, deltasub(L) = #beta#sub(L)R, characterizing all important excitations are available from other experiments and the #gamma#-branching of these states is also known, the only unknown quantity determining sigmasub(#gamma#) is found to be the ratio of the diffuseness parameter of the profile function, d, to its radius, R. The most reliably determined values of d/R, for the target "4"0Ca, imply a rather wide penumbra, consistent with microscopic calculations. (orig.).
Purpose Video-assisted thoracic surgery (VATS) has recently been adopted for complicated anatomical lung resections. During these thoracoscopic procedures, surgeons view the operative field on a two-dimensional (2-D) video monitor and cannot palpate the organ directly, thus frequently encountering anatomical difficulties. This study aimed to estimate the usefulness of preoperative three-dimensional (3-D) imaging of thoracic organs. Methods We compared the preoperative 64-row three-dimensional multidetector computed tomography (3DMDCT) findings of lung cancer-affected thoracic organs to the operative findings. Results In comparison to the operative findings, the branches of pulmonary arteries, veins, and bronchi were well defined in the 3D-MDCT images of 27 patients. Conclusion 3D-MDCT imag...
We study the rates allowed for the Higgs-mediated decays $B_{s,d}^0\\to\\mu\\tau, e\\tau$ and $\\tau\\to \\mu\\mu\\mu, e\\mu\\mu$ in supersymmetric seesaw models, assuming that the only source of lepton flavour violation (LFV) is the renormalization of soft supersymmetry-breaking terms due to off-diagonal singlet-neutrino Yukawa interactions. These decays are strongly correlated with, and constrained by, the branching ratios for $B_{s,d}^0\\to\\mu\\mu$ and $\\tau\\to \\mu(e)\\gamma.$ Parametrizing the singlet-neutrino Yukawa couplings $Y_\
With the ubiquitous availability of commercial VME modules and interface chips many experiments in all branches of Experimental Physics are turning to VME as the module packaging and backplane protocol of choice for application specific modules. The current VME backplane, electrical, and mechanical standards are clearly lacking when it comes to implementing the analogue and digital front end modules that Physics experiments rely on to provide the needed high speed and intelligent solutions to their data collection requirements. To address these needs the European ESONE and American VME-P committees are collaborating with the ANSII and ISO standards committees, and the VME VITA/VSO manufacturers associations, to define standard extensions to the VME protocols for such HEP needs as ``sparse data scans``, standard uses and implementations of previously user defined pins and connectors, standardization of the 9U form factor VME cards etc. This paper reports on the ...
Fatigue crack growth tests of three ferrite-pearlite steels with different size and spacing of pearlite particles, which were uniformly distributed in the ferrite matrix, were carried out to investigate the effect of microstructure on fatigue crack growth behavior in the Paris regime. The fatigue crack growth rates for the three materials did not coincide with each other, even when the crack growth curves were arranged by the effective stress intensity factor range. From in situ observations, crack tip stress shielding phenomena, such as interlocking and branching, were found on the crack wake, which enhanced fatigue crack growth resistance. A small size and spacing of pearlite particle seemed to induce small but frequent crack deflections, which resulted in crack closure phenomena. On the...
This paper investigates the effects of the electric current pulse (ECP) on the interface stability of Al-4.5% Cu alloy during the directional solidification. Experimental results show both the cellular spacing and the mushy zone depth decrease with increasing current density, moreover, the solid-liquid interface morphology transforms from dendritic to cellular or even planar interface. The secondary dendrites are suppressed due to the homogeneous distribution of the solute and the increase of temperature gradient originated from ECP. The decrease of the cellular spacing results from branching of the cellular tip caused by Joule heat of the current exerting on cellular tip.
We explore a novel phenomenon of focused ion beam (FIB) induced bending of carbon nanopillars or cantilever structures. The bending occurs towards the ion beam during scanning. The explanation of this bending has been sought on the basis of a model which considers temperature rise and gradients caused by the impinging ion beam. The process is controllable and reversible, which makes it highly suitable for in situ manipulation to make desired 3D shapes by the piecewise bending of the nanopillars and cantilever structures during their fabrication using electron beam or FIB chemical vapor deposition (EB-CVD or FIB-CVD). Its usefulness in the fabrication of nanosize mechanical components has been demonstrated by making a branch structure from a single cantilever.
The paper presents some aspects relating to the importance of a good communication and cooperation between all factors involved in procurement process at Societatea Nationala 'Nuclearelectrica', SNN. In order to comply with the internal and international rules related to safety in nuclear field and public procurement requirements and for maintaining a high standard of operational performance of Cernavoda NPP, adequate procurement systems were developed by SNN SA. The importance of human factor and the training activities for all personnel from this chain of procurement process is the main key issue to maintain high quality of their activities considering that procurement documents are reviewed and approved before to be issued by all departments involved in procurement process. The specialized department for public acquisition is supervising that the procurement processes initiated at the level of branches, in accordance with their needs and with respect to the ...
Proton and alpha decay from the giant resonance region of {sup 28}Si excited with a 129 MeV alpha particle beam has been measured in coincidence with inelastic alpha particles detected at 0{degree}. The angular correlation data show the presence of decay from both {ital E}0 and {ital E}2 giant resonances. The {ital E}0 giant resonance decays primarily through the {alpha}{sub 0}, {alpha}{sub 1}, {ital p}{sub 0}, and {ital p}{sub 1,2} channels with the branching ratios 18{plus minus}6 %, 24{plus minus}8 %, 23{plus minus}9 %, and 18{plus minus}8 %, respectively. Substantial direct decay is observed.
The purpose of this work was to determine the radiolytic hydrogen gas yield of irradiated CSSX solvent at several temperatures. The active ingredient of this solvent is calix[4]arene-bis-(t-octylbenzo) crown-6, a calixarene crown ether used for cesium complexation. The solvent also contains 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol, a fluorinated alcoholic solvent modifer used to improve the solubility of the calixarene and its cesium complex in the Isopar L diluent. Isopar L is a branch-chain alkane and comprises most of the mixture. Samples of this solution were irradiated to various absorbed ?-ray doses in gas-tight sample containers, which were then sampled for hydrogen gas content. The methods are described below.
Glucose homeostasis requires the tight regulation of glucose utilization by liver, muscle and white or brown fat, and glucose production and release in the blood by liver. The major goal of maintaining glycemia at -5 mM is to ensure a sufficient flux of glucose to the brain, which depends mostly on this nutrient as a source of metabolic energy. This homeostatic process is controlled by hormones, mainly glucagon and insulin, and by autonomic nervous activities that control the metabolic state of liver, muscle and fat tissue but also the secretory activity of the endocrine pancreas. Activation or inhibition of the sympathetic or parasympathetic branches of the autonomic nervous systems are controlled by glucose-excited or glucose-inhibited neurons located at different anatomical sites, mainl...
On 7 May 2009, the Ministry of the Environment set up a working group to evaluate the possible use of biodegradable waste and other biodegradable material flows for energy production and obstacles to promoting their use in the whole production cycle. The deadline for the working group was 31 January 2010. According to its mandate, the working group had to make proposals for the measures needed to promote the energy use of biodegradable waste in order to fulfil the targets of the Government Foresight Report on Long-term Climate and Energy Policy. The working group proposes thirteen measures to be put into operation so that the investments aimed at the energy use of biodegradable waste would grow significantly from the present level. The most important measure is a full ban on depositing biodegradable waste in landfills. The working group sees that the reduction of greenhouse gas emissions from landfills should, in any case, be made more effective and that the planning procedures for ...
Abstract: The basement of the South China Sea (SCS) and adjacent areas can be divided into six divisions (regions) - Paleozoic Erathem graben-faulted basement division in Beibu Gulf, Paleozoic Erathem strike-slip pull-apart in Yinggehai waters, Paleozoic Erathem faulted-depression in eastern Hainan, Paleozoic Erathem rifted in northern Xisha (Paracel), Paleozoic Erathem strike-slip extending in southern Xisha, and Paleozoic-Mesozoic Erathem extending in Nansha Islands (Spratly) waters. The Pre-Cenozoic basement in the SCS and Yunkai continental area are coeval within the Tethyan tectonic domain in the Pre-Cenozoic Period. They are formed on the background of the Paleo-Tethyan tectonic domain, and are important components of the Eastern Tethyan multi-island-ocean system. Three branches of t...
We provide an efficient computational approach to solve the mixed integer programming (MIP) model developed by Tarim and Kingsman [8] for solving a stochastic lot-sizing problem with service level constraints under the static-dynamic uncertainty strategy. The effectiveness of the proposed method hinges on three novelties: (i) the proposed relaxation is computationally efficient and provides an optimal solution most of the time, (ii) if the relaxation produces an infeasible solution, then this solution yields a tight lower bound for the optimal cost, and (iii) it can be modified easily to obtain a feasible solution, which yields an upper bound. In case of infeasibility, the relaxation approach is implemented at each node of the search tree in a branch-and-bound procedure to efficiently sear...
Emission inventories were estimated for the airborne emissions of: Arsenic, Beryllium, Cadmium, Chromium, Cobalt, Copper, Mercury, Manganese, Molybdenum, Nickel, Lead, Antimony, Selenium, Tellur, Thallium, Zinc, Platinum, Palladium, Rhodium, Tin. The inventories were made for the status of 1985 and 1990. A prognosis was given for 1995. The investigations were made for the whole area of the Federal Republic of Germany including the former German Democratic Republic. Working point was an overview about the plant-specific emissions for the various industrial branches and the production statistics. The results are given as total emissions from the existing plants and industrial branches. (orig.) [Deutsch] Es erfolgte eine Abschaetzung der luftseitigen Emissionen fuer die Elemente: Arsen, Beryllium, Cadmium, Chrom, Kobalt, Kupfer, Quecksilber, Mangan, Molybdaen, Nickel, Blei, Antimon, Selen, Tellur, Thallium, Zink, Platin, Palladium, Rhodium und ...
The Fast Wave Current Drive (FWCD) system at DIII-D has increased its available radio frequency (RF) power capabilities with the addition of two new high power transmitters along with their associated transmission line systems. A Sun Sparc-10 workstation, functioning as the FWCD operator console, is being used to control transmitter operating parameters and transmission line tuning parameters, along with acquiring data and making data available for integration into the DIII-D data acquisition system. Labview, a graphical user interface application, is used to manage and control the above processes. This paper will discuss the three primary branches of the FWCD computer control system: transmitter control, transmission line tuning control, and FWCD data acquisition. The main control program developed uses VXI, GPIB, CAMAC, Serial, and Ethernet protocols to blend the three branches together into one cohesive system. The control of the ...
The Ho-Chunk Nation is interested in documenting water-quality conditions in streams adjacent to their Reservation lands in Wisconsin and developing management plans to protect these water resources. The Nation uses these waterways for recreation and as a source for food, and therefore, is dedicated to maintaining and restoring their quality. Ho-Chunk lands encompass more than 10,000 acres ranging primarily over 17 counties in Wisconsin. The study areas for this report include streams adjacent to Ho-Chunk Nation residential lands: Potch-Hah-Chee, Sandpillow, Mission, Bluewing, Chakh Hah Chee, Winnebago Heights, Indian Heights, and Ho-Chunk Village. These residential areas, or housing sites, are located along or near the Middle Branch Embarrass, Black, Lemonweir, and Wisconsin Rivers or their tributaries. Water-quality data were compiled and summarized, and basin maps showing land cover and previous sampling sites are presented. Qualitative assessments of factors ...
In this thesis, the potential to discover supersymmetric signatures in both e"+e"- and #gamma##gamma# colliders evaluated with a Monte Carlo analysis, is discussed. The analysis was focused on the detection of muons, essentially. First, we study the detection of #mu#"+_R#mu#"-_R in e"-e"+ collisions, whose purpose is the measurement of the #mu#_R mass. It was found that an uncertainty of 0.11 GeV (stat) can be achieved. Under the assumption of the real conditions of the ILC photon collider, a study covering the detection of #mu#"+_R#mu#"-_R and #mu#"+_L#mu#"-_L pairs for #sq root#(s_e_"-_e_"+)=0.5 and 0.6 TeV was performed. According to the simulation, a statistical error for the branching ratios of #mu#"#+-#_L#->##chi#"0_1#mu#"#+-# of 0.98% and #mu#"#+-#_L#->##chi#"0_2#mu#"#+-# of 3.97% can be reached. In order to judge the Monte Carlo results, we have used a technique based on a multidimensional fit to evaluate the impact of the ...
Specific structure of biota community condition can used as indicator for the ecosystem stability value or the waters pollution level where the aquatic biota exist. the macro invertebrates as bio indicator organism can used to assess the upper Cisadane Sub River Basin water quality. The grouping and calculation result from family number, Ept presences (sensitive macro invertebrate), Diversity index (H"'), DO value and TOC value showed 5 criteria of water quality as reference site. This criteria is used to determine water quality level from ten branches of rivers in the upper Cisadane Sub River Basin, Cijeruk districts. The biotic index calculation for ASPT (Average Score Per Taxon) and T and T (index Trihadiningrum and Tjindronegoro) is used to asses water quality based on macro invertebrate composition indicator. Both biotic index system support and give the similar evaluation to water quality level from ten branches of river on the upper ...
The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom, or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range of 300 to 1000 K and pressure range of 1 to 10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and ...
Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily uponthe ability to control the conjugation and assembly processes.In the work presented here, we first design a branched DNA scaffold which allows hybridization of DNA-nanocrystal monoconjugates to form discrete assemblies. Importantly, the asymmetry of the branched scaffold allows the formation of asymmetric2assemblies of nanocrystals. In the context of a self-assembled device, this can be considered a step toward the ability to engineer functionally ...
Aim: To evaluate magnetic resonance cholangiography (MRC) with high-resolution dynamic gadolinium-enhanced magnetic resonance imaging (MRI) in determining the imaging features of hilar cholangiocarcinoma that relate to tumour extent and influence resectability. Materials and methods: Twenty-six patients that underwent resection were reviewed. Tumour location and extent, lobar atrophy, the degree of portal vein and hepatic artery involvement were recorded. The findings were correlated with surgical and histopathological findings. Results: Biliary assessment was concordant in 14 and discordant in eight of 14 stented and four of 12 non-stented patients. In 63/82 veins and 43/74 arteries results were fully concordant. The mean sensitivity, specificity, positive and negative predictive values (PPV, NPV) in predicting involvement of the main portal vein (MPV) at surgery were 83.3, 100, 100, and 92.5%; of the left main branch of the portal vein (LPV) were 100, 91.6, 93.3, ...
Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO[sub 2] absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the [ital P] branch of the fundamental absorption band (2150--1950 cm[sup [minus]1]) while the CO[sub 2] vibrational-rotational lines were from the far wing of the [ital R] branch of the [nu][sub 3] fundamental band (2395--2380 cm[sup [minus]1]). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO[sub 2]/N[sub 2] gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak ...
Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO_2 absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the P branch of the fundamental absorption band (2150--1950 cm"-"1) while the CO_2 vibrational-rotational lines were from the far wing of the R branch of the #nu#_3 fundamental band (2395--2380 cm"-"1). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO_2/N_2 gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak overlap. Line strength measurements were made from the corrected ...
Quantitative ecological risk assessment (ERA) is a means whereby the risk posed by a toxicant in any system can be evaluated by comparing the distribution of its measured or modelled concentrations (water quality data (WQD)) with available information on the range of concentrations that are known to adversely affect biota within that, or similar, habitats (dose-response data (DRD)). Initially, the WQD are compared with regulatory criteria (e.g. ANZECC and ARMCANZ, 2000). If they fail this test, then, on the assumption that both data sets comprise subsets of the entire range of concentrations, probability density functions are derived assuming a standard distribution form a typically log-normal. In this paper, AQUARISK has been used to estimate the risk posed by copper in effluent from the Rum Jungle mine site, pre- and post-remediation, and the proportion of taxa likely to be affected in the East Branch (EB) of the Finniss River downstream of the mine. In addition, ...
Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm x 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. ...
Lipiodol, lipid soluble contrast media, was applied to 59 patients, who was clinically suspected to have hepatic tumor, in the Department of Diagnostic Radiology, Seoul National University Hospital. The results of the clinical use of Lipiodol were as follows: 1. The clinical diagnosis was hepatocellular carcinoma (HCC) in 50 cases, cavernous hemangioma in 4 cases, metastasis in one case and others in 4 cases. 2. After hepatic arteriography, Lipiodol only was injected in 28 cases, mixture of Lipiodol and Mitomycin was injected in 22 cases and transcatheter arterial embolization was performed additionally after injection of Lipiodol and Mitomycin in 9 cases. 3. Among the 50 cases of HCC, Lipiodol was accumulated in the lesion in 49 cases. However, similar accumulation of Lipiodol occured in a metastatic cancer and cavernous hemangiomas. 4. Plain radiographic patterns of Lipiodol accumulation could be divided into fine granular type, nodular type and linear or ...
The results of investigation into a new series of Z-even nuclei - precursors of delayed protons (PDP) -"6"5Ge, "8"9Se, "9"3Kr, "8"1Zr, and "8"5Mo are presented. PDP were obtained by irradiation of targets in the following reactions: Zn(He, 2n) "6"5Ge, 22 MeV; "4"0Ca("3"2S, 2 pn) "1"9Se, 100 MeV; "6"0Ni ("1"60, 3 n), "7"3Kr, 75 MeV; "5"2Cr ("3"2S, 3n)"8"1Zr, 110 MeV; "5"6Fe("3"2S, 3n)"8"5Mo, 120 MeV. The targets (self-sustaining foils of thickness approximately 1.2 mg/cm"2) were placed at an angle of 15 deg to the direction of the ion beam. Upon irradiation targets were moved downwards into a measuring position. The spectra of protons, X and gamma-rays, and also the spectra of p - x, p-#gamma#, x - #gamma# coincidences accompanying the decay of "6"5Ge, "6"9Se,"7"3Kr and "8"1Zr, and "8"5Mo were measured. The measured half-lives are equal, to 31.5+-1.9, 27.3+-0.5, 28.5+-1.1, 6.3+-0.5, and 5.6 +-0.9 s respectively. The experimental spectra are compared with the calculated ones. The proton ...
Amperostatic coulometry was applied for the thickness measurement of Sn-Ag hot dip coatings, which comprise an extended Sn-Cu interdiffusion layer. Complementary measurements, notably weight loss, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray fluorescence (XRF), and dynamic secondary ion mass spectroscopy were performed in order to obtain a better interpretation of the coulometry results. Based on the experimental results presented in this article, the three potential changes observed during coulometry measurements are ascribed to (i) the entire dissolution of pure Sn, (ii) the formation of a CuCl salt layer, and (iii) the surface passivation. The measurement of the pure Sn mass is well reproducible despite strong coating thickness variations detected by XRF. Several experimental problems, in particular, a coating undercutting, hamper the determination of the Sn mass in the intermetallic Sn-Cu layer. (19 refs).
PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range (protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of $10^{-8}$). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15 2006 in a $350\\times 600 km$ orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the satellite. In self-trigger ...
Seiberg duality in supersymmetric gauge theories is the claim that two different theories describe the same physics in the infrared limit. However, one cannot easily work out physical quantities in strongly coupled theories and hence it has been difficult to compare the physics of the electric and magnetic theories. In order to gain more insight into the equivalence of two theories, we study the ''e{sup +}e{sup -}'' cross sections into ''hadrons'' for both theories in the superconformal window. We describe a technique which allows us to compute the cross sections exactly in the infrared limit. They are indeed equal in the low-energy limit and the equality is guaranteed because of the anomaly matching condition. The ultraviolet behavior of the total ''e{sup +}e{sup -}'' cross section is different for the two theories. We comment on proposed nonsupersymmetric ...
The authors present a search for excited and exotic muon states {mu}*, conducted using an integrated luminosity of 371 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV at the Tevatron with the CDF II detector. They search for associated production of {mu}{mu}* followed by the decay {mu}* {yields} {mu}{gamma}, resulting in the {mu}{mu}{gamma} final state. They compare the data to model predictions as a function of the mass of the excited muon M{sub {mu}*}, the compositeness energy scale {Lambda}, and the gauge coupling factor f. No signal above the standard model expectation is observed in the {mu}{gamma} mass spectrum. In the contact interaction model, they exclude 107 < M{sub {mu}*} < 853 GeV/c{sup 2} for {Lambda} = M{sub {mu}*}; in the gauge-mediated model, they exclude 100 < M{sub {mu}*} < 410 GeV/c{sup 2} for f/{Lambda} = 10{sup -2} GeV{sup -1}. These 95% confidence level exclusions extend previous limits and are the first ...
A dipole magnet based on the common coil design, using prereacted Nb{sub 3}Sn superconductor, is under development at Fermilab, for a future Very Large Hadron Collider. This magnet has some innovative design and technological features such as single layer coils, a 22 mm wide 60-strand Rutherford type cable and stainless steel collars reinforced by horizontal bridges inserted between coil blocks. Both left and right coils are wound simultaneously into the collar structure and then impregnated with epoxy. In order to optimize the design and fabrication techniques an R&D program is underway. The production of cables with the required characteristics was shown possible. Collar laminations were produced, assembled and tested in order to check the effectiveness of the bridges and the validity of the mechanical design. A mechanical model consisting of a 165 mm long section of the magnet straight section was assembled and tested. This paper summarizes the status of ...
We consider the physics and collider phenomenology of quirks that transform nontrivially under QCD color, SU(2)_W as well as an SU(N)_{ic} infracolor group. Our main motivation is to show that the recent Wjj excess observed by CDF naturally arises in quirky models. The basic pattern is that several different quirky states can be produced, some of which beta-decay during or after spin-down, leaving the lightest electrically neutral quirks to hadronize into a meson that subsequently decays into gluon jets. We analyze LEP II, Tevatron, UA2, and electroweak precision constraints, identifying the simplest viable models: scalar quirks ("squirks") transforming as color triplets, SU(2)_W triplets and singlets, all with vanishing hypercharge. We calculate production cross sections, weak decay, spin-down, meson decay rates, and estimate efficiencies. The novel features of our quirky model includes: quirkonium decay proceeds into a pair of gluon jets, without a b-jet ...
New measurements of the spin structure functions of the proton and deuteron g{sub 1}{sup p}(x, Q{sup 2}) and g{sub 1}{sup d}(x, Q{sup 2}) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W < 2 GeV), the data and QCD fits are in good agreement in both magnitude and Q{sup 2} dependence for Q{sup 2} > 1.7 GeV{sup 2}/c{sup 2}. This ''global'' duality appears to result from cancellations among the prominent ''local'' resonance regions: in particular strong {sigma}{sub 3/2} contributions in the {Delta}(1232) region appear to be compensated by strong {sigma}{sub 1/2} contributions in the resonance region centered on 1.5 GeV. These results are encouraging for the extension of NLO QCD fits to lower W and Q{sup 2} than have been used previously.
We exhibit static solutions of multi-flavour QCD in two dimensions that have the quantum numbers of baryons and mesons, constructed out of quark and anti-quark solitons. In isolation the latter solitons have infinite energy, corresponding to the presence of a string carrying the non-singlet colour flux off to spatial infinity. When $N_c$ solitons of this type are combined, a static, finite-energy, colour singlet solution is formed, corresponding to a baryon. Similarly, static meson solutions are formed out of a soliton and an anti-soliton of different flavours. The stability of the mesons against annihilation is ensured by flavour conservation. The static solutions exist only when the fundamental fields of the bosonized Lagrangian belong to $U(N_c{\\times}N_f)$ rather than to $SU(N_c) \\times U(N_f)$. Discussion of flavour symmetry breaking requires a careful treatment of the normal ordering ambiguity. Our results can be viewed as a derivation of the constituent quark model in QCD$_2$, ...
Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing and novel jet substructure observables, we find that a multivariate approach can filter out over 95% of the gluon jets while keeping more than half of the light-quark jets. Moreover, a combination of two simple variables, the charge track multiplicity and the pT-weighted linear radial moment (girth), can achieve similar results. While this pair appears very promising, our study is only Monte Carlo based, and other discriminants may work better with real data in a realistic experimental environment. To that end, we explore many other observables constructed using different jet sizes and parameters, and highlight those that deserve further theoretical and experimental scrutiny. Additional information, including distributions of around 10,000 ...
Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the ...
In this paper we will report on the operation and the performance of the ATLAS data-flow system during the 2010 physics run of the Large Hadron Collider (LHC) at 7TeV. The data-flow system is responsible for reading out, formatting and conveying the event data, eventually saving the selected events into the mass storage. By the second quarter of 2010, for the first time, the system will be capable of the full event building capacity and improved data-logging throughput. We will in particular detail the tools put in place to predict and track the system working point, with the aim of optimizing the bandwidth and the computing resource sharing, and anticipate possible limits. Naturally, the LHC duty cycle, the trigger performance, and the detector configuration influence the system working point. Therefore, numerical studies of the data-flow system capabilities have been performed considering different scenarios. This is crucial for the first phase of the LHC ...
In this paper we will report on the operation and the performance of the ATLAS data-flow system during the 2010 physics run of the Large Hadron Collider (LHC) at 7 TeV. The data-flow system is responsible for reading out, formatting and conveying the event data, eventually saving the selected events into the mass storage. By the second quarter of 2010, for the first time, the system will be capable of the full event building capacity and improved data-logging throughput. We will in particular detail the tools put in place to predict and track the system working point, with the aim of optimizing the bandwidth and the computing resource sharing, and anticipate possible limits. Naturally, the LHC duty cycle, the trigger performance, and the detector configuration influence the system working point. Therefore, numerical studies of the data-flow system capabilities have been performed considering different scenarios. This is crucial for the first phase of the LHC ...
We propose to study the open charm effects in $e^+ e^-\\to J/\\psi\\eta$, $J/\\psi\\pi^0$ and $\\phi\\eta_c$. We show that the exclusive cross section lineshapes of these processes would be strongly affected by the open charm effects. Since the final state light meson productions are through soft gluon radiations, we assume a recognition of this soft process via charmed meson loops at hadronic level. A unique feature among these three reactions is that the $D\\bar{D^*}+c.c.$ open channel is located in a relatively isolated energy, i.e. $\\sim 3.876$ GeV, which is sufficiently far away from the known charmonia $\\psi(3770)$ and $\\psi(4040)$. Therefore, the cross section lineshapes of these reactions may provide an opportunity for singling out the open charm effects with relatively well-defined charmonium contributions. In particular, we find that reaction $e^+ e^-\\to J/\\psi\\pi^0$ is sensitive to the open charm $D\\bar{D^*}+c.c.$ Due to the dominance of the ...
ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). Some specific calibration tasks are performed regularly for each of the 18 ALICE sub-detectors in order to achieve most accurate physics measurements. These procedures involve events analysis in a wide range of experimental conditions, implicating various trigger types, data throughputs, electronics settings, and algorithms, both during short sub-detector standalone runs and long global physics runs. A framework was designed to collect statistics and compute some of the calibration parameters directly online, using resources of the Data Acquisition System (DAQ), and benefiting from its inherent parallel architecture to process events. This system has been used at the experimental area for one year, and includes more than 30 calibration routines in production. This paper ...
The LHCb experiment that is being settled in CERN is dedicated to the study of CP violation and rare decays in the field of beauty hadrons. The phenomenological background necessary to an adequate understanding of the physics of flavor is presented in the first chapter, it is shown how the flavordynamics can open the way to new physics. The second chapter is dedicated to a brief presentation of the LHCb detector. Two aspects of the design of the muon trigger are more detailed: the radiation resistance of the opto-electronic transmitters and the simulated performances of the trigger. The third chapter reviews the tasks linked to the tagging of the savors of B mesons which will be an important step in all the experiments made at LHCb. The recent progress in heavy savor physics as well as the expected contribution of LHCb in this field are presented in the fourth chapter, especially the search for new physics in penguin diagrams b {yields} s.
The availability of new, high-intensity, cold and thermal neutron sources has opened the possibility of performing high-precision fundamental neutron physics experiments, including measurements that study the hadronic weak interaction and standard model test measurements, using neutron decay. The observables in these experiments are usually correlated with the direction of neutron polarization and are often very small (10 8 10 6). Mott-Schwinger scattering of polarized neutrons can produce spin-dependent shifts in beam centroids, which has the potential to produce significant systematic effects for these types of experiments. An accurate calculation of this process for neutral atoms and basic molecules has not been carried out for low neutron energies. In this work, we derive a general expression for the electromagnetic (Mott-Schwinger) contributions to the analyzing power for low-energy neutron scattering. We obtain numerical results for 11 nuclei in the range of ...
PAMELA is a satellite borne experiment designed to study with great accuracy cosmic rays of galactic, solar, and trapped nature in a wide energy range protons: 80 MeV-700 GeV, electrons 50 MeV-400 GeV). Main objective is the study of the antimatter component: antiprotons (80 MeV-190 GeV), positrons (50 MeV-270 GeV) and search for antimatter with a precision of the order of 10^-8). The experiment, housed on board the Russian Resurs-DK1 satellite, was launched on June, 15, 2006 in a 350*600 km orbit with an inclination of 70 degrees. The detector is composed of a series of scintillator counters arranged at the extremities of a permanent magnet spectrometer to provide charge, Time-of-Flight and rigidity information. Lepton/hadron identification is performed by a Silicon-Tungsten calorimeter and a Neutron detector placed at the bottom of the device. An Anticounter system is used offline to reject false triggers coming from the satellite. In self-trigger mode the ...
The non-thermal supernova remnant RX J1713.7-3946 (G347.3-0.5) has recently been shown to be a site of cosmic ray (CR) electron acceleration to TeV energies (Muraishi et al. 2000). Here we present evidence that this remnant is also accelerating CR nuclei. Such nuclei can interact with ambient interstellar gas to produce high energy gamma-rays via the decay of neutral pions. We associate the unidentified EGRET GeV gamma- ray source 3EG J1714-3857 with a massive (~3*10 5 Mo) and dense (~500 nucleons cm -3) molecular cloud interacting with RX J1713.7-3946. Direct evidence for such interaction is provided by observations of the lowest two rotational transitions of CO in the cloud; as in other clear cases of interaction, the CO(J=2-1)/CO(J=1-0) ratio is significantly enhanced. Since the cloud is of low radio and X-ray brightness, CR electrons cannot be responsible for the bulk of its GeV emission there. A picture thus emerges where both electrons and nuclei are being accelerated by the SNR: ...
We present several recent results from the BaBar collaboration in the areas of initial state radiation physics and transition form factors. An updated study of the processes e+e- -> K+K-pi+pi- and e+e- -> K+K-pi0pi0 provides an improved understanding of the Y(2175) meson. A very precise study of the process e+e- -> pi+pi- improves the precision on the calculated anomalous magnetic moment of the muon and provides by far the best information on excited rho states. Our previous measurements of the timelike transition form factors (TFF) of the eta and eta' mesons at Q^2=112 GeV^2, combined with new measurements of the their spacelike TFFs and those of the pi0 and eta_c mesons, provide powerful tests of QCD and models of the distribution amplitudes of quarks inside these mesons. The eta_c TFF shows the expected behavior over the Q^2 range 1-50 GeV^2, and we are sensitive to next-to-leading-order QCD corrections. The eta and eta' TFFs are consistent with expected behavior, but those ...
Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed ...
The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 m and a length of 5.4 m representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure, providing stability within the working conditions of a 4 T solenoid magnetic field at ?10oC. Knowledge of the position of the silicon detectors at the level of 100 ?m is needed for an efficient pattern recognition of charged particle tracks. Metrology methods are used to survey tracker subdetectors and the integrated Laser Alignment System (LAS) provides absolute positioning of support ...
The aim of this set of lectures is to review different avenues of electroweak symmetry breaking explored over the years. This constitutes a timely exercise as the world's largest and the highest energy particle accelerator, namely, the Large Hadron Collider (LHC) at CERN near Geneva, is all set to start running whose primary mission is to unravel the mysteries of electroweak phase transition. In the beginning, we discuss the Standard Model Higgs mechanism. After that we review the Higgs sector of the Minimal Supersymmetric Standard Model. Then we take up three relatively recent ideas: Little Higgs, Gauge-Higgs Unification, and Higgsless scenarios. For the latter three cases, we present the basic ideas and restrict our illustrations to some instructive toy models, as our intention is rather to provide an intuitive feel of the underlying dynamics than to get into an in-depth analysis of realistic scenarios. Wherever possible, we provide enough pedagogical details, ...
Diffuse {gamma}-ray emission produced by the interaction of cosmic-ray particles with matter and radiation in the Galaxy can be used to probe the distribution of cosmic rays and their sources in different regions of the Galaxy. With its large field of view and long observation time, the Milagro Gamma Ray Observatory is an ideal instrument for surveying large regions of the Northern Hemisphere sky and for detecting diffuse {gamma}-ray emission at very high energies. Here, the spatial distribution and the flux of the diffuse {gamma}-ray emission in the TeV energy range with a median energy of 15 TeV for Galactic longitudes between 30{sup o} and 110{sup o} and between 136{sup o} and 216{sup o} and for Galactic latitudes between -10{sup o} and 10{sup o} are determined. The measured fluxes are consistent with predictions of the GALPROP model everywhere except for the Cygnus region (l {element_of} [65{sup o}, 85{sup o}]). For the Cygnus region, the flux is twice the predicted value. This ...
We summarize the predictions of different models for total #gamma##gamma# cross-sections. The experimentally observed rise of #sigma#_#gamma#_#gamma# with s radical _#gamma#_#gamma#, faster than that for #sigma#_p_-_b_a_r_p, #sigma#_#gamma#_p is in agreement with the predictions of the Eikonalized Minijet Models as opposed to those of the Regge-Pomeron models. We then show that a measurement of #sigma#_#gamma#_#gamma# with an accuracy of < or approx. 8-9% (6-7%) is necessary to distinguish among different Regge-Pomeron type models (the different parameterisations of the EMM models) and a precision of < or approx. 20% is required to distinguish the predictions of the EMMs and of those models which treat 'photon like a proton', for the energy range 300< s radical_#gamma#_#gamma# <500 GeV. We further show that the difference in model predictions for #sigma#_#gamma#_#gamma# of about a factor 2 at s radical _#gamma#_#gamma# = 700 GeV reduces to #approx# 30% when folded with ...
Background and purpose: In order to investigate the feasibility, toxicity and antitumor efficacy of hyperfractionated radiation therapy, 37 adult patients with incompletely resected supratentorial low-grade glioma were entered into a phase II study. Materials and methods: The radiation therapy dose was 55 Gy in 50 fractions in 25 treatment days over 5 weeks to the tumor plus a 2-cm margin, with an additional 17.6 Gy given in 16 fractions in 8 treatment days over 1.5 weeks to the tumor plus a 1-cm margin, using 1.1 Gy b.i.d. fractionation with a 6 h interfraction interval. The total tumor dose was 72.6 Gy in 66 fractions in 33 treatment days over 6.5 weeks. Results: The median survival time (MST) for all 37 patients has not yet been attained, while 5- and 7-year survival rates were 75% and 69%, respectively. The median time to tumor progression (MTP) has also not yet been attained, while 5- and 7-year ...