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101.
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Summary The rheological characteristics of synovial fluid have been examined with aWeissenberg Rheogoniometer.Rheological evidence for the existence of a macromolecular complex in normal but not in inflammatory joint fluids has been deduced from experiments with hydrogen bond breaking agents.Further flow experiments with measurements of relaxation time and activation energy for viscous flow appear to support the contention that macromolecular complexes do exist in normal fluid and that dilution alone does not account for their dissolution in inflammatory joint diseases.Proteolytic enzyme extracts from inflammatory synovial fluid appear to have no effect on the flow characteristics of normal synovial fluid.Attempts to identify the nature of the macromolecular complex by analytical ultracentrifugation were not successful.It is concluded that rheological techniques offer a way of investigating macromolecular interactions when classical chemical methods may not be appropriate.
Paper presented to the British Society of Rheology Conference on Rheology in Medicine and Pharmacy, London, April 14–15, 1970. 相似文献
Zusammenfassung Es ist gut bekannt, daß Synovialflüssigkeit von rheumatisch-veränderten Gelenken eine geringere Viskosität hat, weniger Nicht-Newtonsches Verhalten zeigt und weniger elastisch ist als Synovialflüssigkeit von normalen Gelenken. Thixotropie, die normale Synovialflüssigkeit charakterisiert, ist in Synovialflüssigkeit von kranken Gelenken verringert oder nicht vorhanden. In dieser Veröffentlichung werden rheologische Experimente beschrieben, die mit normaler und rheumatisch veränderter Synovialflüssigkeit durchgeführt worden sind, um diese Veränderungen in Theologischen Besonderheiten zu erklären.Das Fließverhalten wurde mit einemWeissenberg-Rheogoniometer (Typ R 16) unter kontinuierlicher Schubbelastung untersucht.Andere Forscher haben gezeigt, daß in rheumatischer Synovialflüssigkeit die Hyaluronsäure abgebaut und daß die Konzentration an Hyaluronsäure-Eiweißkomplex reduziert wird. In-vitro-Experimente haben in unserem Labor auch gezeigt, daß Zugabe von wasserstoffbrückenzerstörenden Reagenzien zu normaler Synovialflüssigkeit das Fließverhalten von dieser der rheumatischen Synovialflüssigkeit sehr ähnlich machen. Rheologische Daten, die in Detail gegeben werden, zeigen, daß in normaler Synovialflüssigkeit ein makromolekularer Komplex vorhanden ist, der in rheumatischer Flüssigkeit dissoziiert.Die Art und Bedeutung dieses makromolekularen Komplexes sind weiter untersucht worden, besonders durch Bestimmung der Aktivierungsenergien für laminares Fließen von mehreren Synovialflüssigkeiten. Diese Daten wurden gestützt durch Ergebnisse von analytischen Ultrazentrifugen-Experimenten und durch weitere rheologische Experimente mit Extrakten von proteolytischen Enzymen.
Paper presented to the British Society of Rheology Conference on Rheology in Medicine and Pharmacy, London, April 14–15, 1970. 相似文献
104.
We have measured 1H and 19F NMR relaxation times T1, T1ρ, and T2, and diffusion constants, in trace penetrants hexafluorobenzene and n-hexadecane dissolved in stretched cis-polyisoprene, as function of temperature, rubber elongation, and angle with respect to the stretch direction. Values of T1 and T2 in the rubber were also measured. At all temperatures (—40 ≤ T ≤ 85°C), T1 in rubber and penetrants is isotropic and independent of elongation; the differences between rubber and penetrants are related to penetrant diffusion. All T2 above—15°C are anisotropic and elongation dependent, and follow a motional narrowing model. For the penetrants, averaging the dipolar interactions implies averaging over a diffusion path; this correctly reproduces the observed much higher T2 anisotropy in the penetrants. Penetrant diffusion rates, however, are essentially isotropic and elongation independent. These effects depend only weakly on the shape of the penetrant molecules. 相似文献
105.
The reorientation effect in Coulomb excitation has been used to measure the following static quadrupole moments: . Interference effects from higher excited states have been included in the analysis, with the signs of the E2 matrix elements taken from an anharmonic model. The value obtained for is in disagreement with two previous measurements. We attribute the discrepancy to the smaller internucleon separation distances involved in the previous experiments, which can cause deviations from Coulomb excitation cross sections. The other quadrupole moments have not been measured previously. The B (E2: 0+ → 2+) measured were: . From the angular distribution of the de-excitation γ-rays of the Pb nuclei following recoil into vacuum, we have determined the following (two standard deviations), . Our value of is in agreement with a previous measurement. 相似文献
106.
Hinson JW Huang GS Lee J Miller DH Pavlunin V Rangarajan R Sanghi B Shibata EI Shipsey IP Cronin-Hennessy D Park CS Park W Thayer JB Thorndike EH Coan TE Gao YS Liu F Stroynowski R Artuso M Boulahouache C Blusk S Dambasuren E Dorjkhaidav O Mountain R Muramatsu H Nandakumar R Skwarnicki T Stone S Wang JC Csorna SE Danko I Bonvicini G Cinabro D Dubrovin M McGee S Bornheim A Lipeles E Pappas SP Shapiro A Sun WM Weinstein AJ Briere RA Chen GP Ferguson T Tatishvili G Vogel H Watkins ME Adam NE 《Physical review letters》2005,94(19):191801
Using the CLEO detector at the Cornell Electron Storage Ring, we have studied the distribution of kinematic variables in the decay lambda(+)(c)lambda--> e(+)nu(e). By performing a four-dimensional maximum likelihood fit, we determine the form factor ratio, R= f(2)/f(1) = -0.31 +/- 0.05(stat) +/- 0.04(syst), the pole mass, M(pole) = [2.21 +/- 0.08(stat) +/- 0.14(syst)] GeV/c(2), and the decay asymmetry parameter of the lambda(+)(c), alpha (lambda(c)) = -0.86 +/-0.03(stat) +/- 0.02(syst), for q(2) = 0.67 (GeV/c(2))(2). We compare the angular distributions of the lambda(+)(c) and lambda(-)(c) and find no evidence for CP violation: A(lambda(c)) = (alpha(lambda(c)) + alpha (lambda(c)))/(alpha(lambda(c))-alpha(lambda(c))) = 0.00 +/- 0.03(stat) +/- 0.01(syst) +/- 0.02, where the third error is from the uncertainty in the world average of the CP-violating parameter, A(lambda), for ppi(-). 相似文献
107.
Adams GS Chasse M Cravey M Cummings JP Danko I Napolitano J Cronin-Hennessy D Park CS Park W Thayer JB Thorndike EH Coan TE Gao YS Liu F Stroynowski R Artuso M Boulahouache C Blusk S Butt J Dambasuren E Dorjkhaidav O Menaa N Mountain R Muramatsu H Nandakumar R Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Bornheim A Pappas SP Weinstein AJ Briere RA Chen GP Ferguson T Tatishvili G Vogel H Watkins ME Adam NE Alexander JP Berkelman K Cassel DG 《Physical review letters》2005,94(1):012001
The decay branching fractions of the three narrow Upsilon resonances to mu(+)mu(-) have been measured by analyzing about 4.3 fb(-1) e(+)e(-) data collected with the CLEO III detector. The branching fraction B(Upsilon(1S)-->mu(+)mu(-))=(2.49+/-0.02+/-0.07)% is consistent with the current world average, but B(Upsilon(2S)-->mu(+)mu(-))=(2.03+/-0.03+/-0.08)% and B(Upsilon(3S)-->mu(+)mu(-))=(2.39+/-0.07+/-0.10)% are significantly larger than prior results. These new muonic branching fractions imply a narrower total decay width for the Upsilon(2S) and Upsilon(3S) resonances and lower other branching fractions that rely on these decays in their determination. 相似文献
108.
Huang GS Miller DH Pavlunin V Sanghi B Shibata EI Shipsey IP Adams GS Chasse M Cummings JP Danko I Napolitano J Cronin-Hennessy D Park CS Park W Thayer JB Thorndike EH Coan TE Gao YS Liu F Stroynowski R Artuso M Boulahouache C Blusk S Butt J Dambasuren E Dorjkhaidav O Menaa N Mountain R Muramatsu H Nandakumar R Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Mahmood AH Csorna SE Bonvicini G Cinabro D Dubrovin M Bornheim A Lipeles E Pappas SP Weinstein AJ Briere RA Chen GP Ferguson T 《Physical review letters》2005,94(1):011802
We investigate the decays D(0)-->pi(-)l(+)nu and D(0)-->K(-)l(+)nu, where l is e or mu, using approximately 7 fb(-1) of data collected with the CLEO III detector. We find R(0) identical with B(D(0)-->pi(-)e(+)nu)/B(D(0)-->K(-)e(+)nu)=0.082+/-0.006+/-0.005. Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and R(0) gives |f(pi)(+)(0)|(2)|V(cd)|(2)/|f(K)(+)(0)|(2)|V(cs)|(2)=0.038(+0.006+0.005)(-0.007-0.003). 相似文献
109.
He Q Muramatsu H Park CS Thorndike EH Coan TE Gao YS Liu F Artuso M Boulahouache C Blusk S Butt J Dorjkhaidav O Li J Menaa N Mountain R Nandakumar R Randrianarivony K Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Briere RA Chen GP Chen J Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Crede V Duboscq JE Ecklund KM Ehrlich R Fields L Galik RS Gibbons L Gittelman B Gray R Gray SW Hartill DL 《Physical review letters》2005,95(22):221802
Using 0.8 x 10(6) D+ D- pairs collected with the CLEO-c detector at the psi(3770) resonance, we have searched for flavor-changing neutral current and lepton-number-violating decays of D+ mesons to final states with dielectrons. We find no indication of either, obtaining 90% confidence level upper limits of B(D+ --> pi+ e+ e-) < 7.4 x 10(-6), B(D+ --> pi- e+ d+) < 3.6 x 10(-6), B(D+ --> K+ e+ e-) < 6.2 x 10(-6), and B(D+ --> K- e+ e+) < 4.5 x 10(-6). 相似文献
110.
In his 1961 paper, Marcel Golay showed how the search for pairs of binary sequences of length with complementary autocorrelation is at worst a problem. Andres, in his 1977 master's thesis, developed an algorithm which reduced this to a search and investigated lengths up to 58 for existence of pairs. In this paper, we describe refinements to this algorithm, enabling a search at length 82. We find no new pairs at the outstanding lengths 74 and 82. In extending the theory of composition, we are able to obtain a closed formula for the number of pairs of length generated by a primitive pair of length . Combining this with the results of searches at all allowable lengths up to 100, we identify five primitive pairs. All others pairs of lengths less than 100 may be derived using the methods outlined.