A station for the investigation of the fluorescence intensity and anisotropy decay of biological objects is described. The station has been installed on the synchrotron radiation (SR) source S-60 of ...P.N. Lebedev Physical Institute and can be extended to investigations of the spatial structure of lipoproteins and biological membranes.
One of the new methods of studying the structure and dimensions of biological membranes is based on the Förster's nonradiative energy transfer between special molecules, the so-called 'membrane ...fluorescent probes'. Further development of the approach is presented in this article. It consists of the combined use of the time-resolved and steady-state fluorescence data with subsequent computer simulation of the energy transfer in membranes. Anthracene as an energy donor, and 4-p-(dimethylamino)styryl-N-dodecylpyridinium (DSP-12) or 4-dimethylaminochalcone (DMC) as energy acceptors were bound with artificial phospholipid membrane vesicles ('liposomes'). The synchrotron radiation was used as an impulse source for the excitation light. The steady-state fluorescence data permit the area of possible probe localization in membranes to be distinguished, while the kinetic data allow them to be narrowed significantly. There is a good agreement between the obtained localization and our present-day knowledge of lipid bilayer structure. The accuracy of the method is ca. several Angströms.
The
Q
2 dependence of the structure function ratio
F
2
Sn/
F
2
C for 0.01 <
x < 0.75 and 1 <
Q
2 < 140 GeV
2 is reported. For
x < 0.1 the size of shadowing decreases with ln
Q
2 and the maximum rate ...is about 0.04 at
x = 0.01. The rate decreases with
x and is compatible with zero for
x ⩾ 0.1. The difference
R
Sn −
R
C, where
R is the ratio of longitudinally to transversely polarised virtual photon absorption cross sections, is also given. No dependence on
x is seen and the average value is 0.040 ± 0.021 (stat.) ± 0.026 (syst.) at a mean
Q
2 of 10 GeV
2.
We present a new measurement of the spin-dependent structure function
g
1
d of the deuteron from deep inelastic scattering of 190 GeV polarized muons on polarized deuterons. The results are combined ...with our previous measurements of
g
1
d. A perturbative QCD evolution in next-to-leading order is used to compute
g
1
d(
x) at a constant
Q
2. At
Q
2 = 10 GeV
2, we obtain a first moment
Γ
1
d=∫
1
d
g
1
dd
x=0.041±0.008, a flavour-singlet axial charge of the nucleon
a
0 = 0.30 ± 0.08, and an axial charge of the strange quark
a
s = −0.09 ± 0.03. Using our earlier determination of
Γ
1
p, we obtain
Γ
1
p −
Γ
1
m = 0.183 ± 0.035 at
Q
2 = 10GeV
2. This result is in agreement with the Bjorken sum rule which predicts
Γ
1
p −
Γ
1
n = 0.186 ± 0.002 at the same
Q
2.
The aim of the study was to evaluate the level of proinflammatory cytokines (tumor necrosis factor-α TNF-α, interleukin-6 IL-6), anti-inflammatory cytokine (interleukin-10 IL-10), and acute-phase ...proteins (haptoglobin Hp and serum amyloid A SAA) in serum and uterine washings in cows that developed endometritis during the early postpartum period. The study was carried out on 40 cows. The experimental group consisted of 20 cows with subclinical endometritis and the control group of 20 cows without endometritis. Analyses in both groups of cows were carried out at 5, 22, and 40 days postpartum (DPP). Experimental material consisted of the blood serum and uterine washings. The levels of the following cytokines: TNF-α, IL-6, IL-10 and acute-phase proteins: Hp and SAA were determined using ELISA. Our study reported that the levels of TNF-α, IL-6, IL-10, Hp, and SAA at 22 DPP were higher in cows with subclinical endometritis (P < 0.001). The levels of TNF-α (P = 0.01), IL-6 and IL-10 (P = 0.001), and Hp (P < 0.001) at 40 DPP were higher in cows with subclinical endometritis compared to healthy cows. The level of IL-10 in uterine washings at 5 DPP was higher (P = 0.001), whereas of SAA was lower (P = 0.01) in cows with subclinical endometritis. At 22 DPP, the levels of IL-6, IL-10, and Hp were higher (P < 0.001) in cows with endometritis. At 40 DPP, the level of TNF-α was lower, whereas these of IL-10 and Hp were elevated (P < 0.001) in cows with endometritis compared to healthy cows. The results indicate that the evaluation of the levels of cytokines and Hp in serum, but primarily in uterine washings, can be an important diagnostic indicator in cows that developed subclinical endometritis. High levels of IL-10 in cows with subclinical endometritis may contribute to the weakening of local resistance mechanisms of the uterus and lead to the persistence of the inflammation in the postpartum period. The present study also shows that the simultaneous examination of selected parameters of antagonistic interactions allows for better assessment of the current state of local immunity in the uterus.
Z.Phys. C66 (1995) 591-600 A description and a detailed comparison of the Mo and Tsai and the Dubna
radiative correction schemes is presented. Numerical comparisons made in the
kinematical region of ...the NMC high energy deep inelastic electroproduction
experiment are discussed. An overall agreement between the two approaches in
the region of low $x$ and high $y$, where the radiative corrections are
largest, is better than 2$\%$.
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