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Advanced glycation end-product-formation is thought to play a role in the development of diabetic angiopathy. By altering the structure of different extracellular matrix components advanced glycation end-products might affect vascular and glomerular permeability. In this study we investigated the effect of treatment with an inhibitor of advanced glycation end-product-formation, aminoguanidine, on vascular permeability and the development of albuminuria in streptozotocin-induced diabetic rats. Male Wistar Rp rats were randomized into a control group, a diabetic group, and an aminoguanidine-treated diabetic group. After 8 weeks, 24-h urine collections were taken and rats were implanted with an arterial and a venous catheter. Mean arterial blood pressure was determined by intra-arterial measurement. Regional albumin clearances were assessed in the eye, ileum, lung, skeletal muscle and skin using an isotope technique. Mean arterial pressure in the diabetic group was significantly lower in the control and aminoguanidine-treated groups ( p<0.02). Regional albumin clearances were significantly increased in all tissues of diabetic rats compared to control rats ( p<0.05). Aminoguanidine treatment of diabetic rats resulted in a significant decrease of regional albumin clearance in all tissues except the lung ( p<0.05, lung p=0.07). The development of albuminuria in diabetic rats however, was not affected by aminoguanidine. [ABSTRACT FROM AUTHOR]

Two- and three-particle rapidity correlations are analyzed in K p and π p-interactions at 250 GeV/c. The main contribution to the two- and three-particle correlation functions comes from mixing of events of different multiplicity. The (short range) two-particle correlation remaining after exclusion of mixing is significantly larger for (+−) than for the equal charge combinations, and is positive for a wider range in rapidity difference. FRITIOF and a 2-string DPM are excluded by our data. A quark-gluon (multi-)string model can describe our inclusive correlation function, but needs to be tuned on the short range part. The multiplicity mixing part increases much faster with increasing energy than the short range part. In the central region, our correlation is similar to that observed in e e and μ p collisions at similar energy. [ABSTRACT FROM AUTHOR]

Quasi-elastic scattering with central dipion cluster production is studied in π p and K p interactions at 250 GeV/c. The cross section of double pomeron exchange is obtained as σ(π p →π(ππ) p)=24 ±5 µb and σ( K p→ K(ππ) p)=19 ±5 µb. The low energy pomeron-pomeron cross section is estimated for the first time. [ABSTRACT FROM AUTHOR]

An analysis is presented of the rapidity and transverse momentum distributions and of the nuclear stopping power in collisions of π and K mesons with Al and Au nuclei at 250 GeV/c. The experimental results are compared to predictions of the additive quark model and the dual parton model. The AQM offers an overall consistent description of the data in this experiment. The DPM reproduces reasonably well the rapidity spectra in the central and projectile fragmentation regions, but fails to describe the nuclear stopping power. [ABSTRACT FROM AUTHOR]

Collective characteristics are studied of hadrons produced in beam fragmentation of non-single-diffractive π p-interactions at 250 GeV/c. An attempt is made to obtain experimental information on the properties of leading cluster production and fragmentation. On average, the leading cluster carries 0.8±0.1 of the incident momentum, so that the mean value of the inelasticity coefficient of 〈 k〉=0.2±0.1 is significantly smaller than that deduced from leading single hadron spectra. The momentum transfer distribution shows that nonsingle-diffractive processes are less peripheral than diffraction dissociation. The analysis of thrust and sphericity shows jet-like structure of pion fragmentation, that of the charge flow an average forward charge of 〈 Q〉=0.45±0.04, in agreement with the average charge of the beam valence quarks. Our data are compared to diffraction dissociation and to the Fritiof model. [ABSTRACT FROM AUTHOR]

A triple Regge analysis is performedof inclusive Λ production in the proton fragmentation region of K→Λ+ X and π→ Λ+ X at 250 GeV/c. Slope and intercept of the leading strange meson trajectory are determined. The results obtained here are compared with those of other experiments. [ABSTRACT FROM AUTHOR]

The inclusive production of neutral kaons is studied in K p and π p interactions at 250 GeV/c. Total and semi-inclusive cross sections and average kaon multiplicities are presented and compared with the data at lower energies. The longitudinal and transverse momentum distributions and their energy dependence are analyzed. The results are interpreted in the framework of recent parton models. [ABSTRACT FROM AUTHOR]

The negative binomial distribution (NBD) is fitted to all charged and to negative particle multiplicity distributions in restricted rapidity intervals, both in the forward and backward c.m. hemispheres of positive meson interactions on Al and Au nuclei. For negative particle multiplicity distributions, the NBD parameters are also determined as a function of n, the number of grey tracks, corresponding to varying number of intranuclear collisions. The data are interpreted in terms of the clan picture of Giovannini and Van Hove and compared to the MCMHA and Fritiof models. Both models reproduce quite well the global multiplicity distributions, but not when sub-samples are considered with fixed number of grey tracks. Regularities are better visible on the parton than on the particle level. [ABSTRACT FROM AUTHOR]

We report on a study of ρ, ρ, ω, $$\bar K^{*0} (892)$$ and K (892) inclusive production in π p interactions at 250 GeV/ c, for ρ, $$\bar K^{*0} (892)$$ for the first time in a π p experiment. The data are compared with K p data in the same experiment, with results of other experiments and with quark-parton models. Interesting differences are found between ρ and ω production. [ABSTRACT FROM AUTHOR]

We present data on the production of the baryons Λ, $$\bar \Lambda $$ , p and of the baryon resonances Σ (1385) and Δ (1232) in K p and π p interactions at 250 GeV/c. Results are given on total and semi-inclusive cross sections, Feynman- x spectra, transverse momentum distributions and Λ polarization. The data are compared with measurements at lower energies, with deep inclastic lepton nucleon data and with predictions of quark-parton models. The models underestimate Λ production in the central c.m. region, a feature also seen in recent heavy-ion data. This failure can be cured in JETSET 6.3 by adjustment of the di-quark break-up probability. [ABSTRACT FROM AUTHOR]

Data on the reactions ( K /π) p→( K /π) pππ and ( K /π) p→( K /π) p2π2π, obtained with the European Hybrid Spectrometer, are presented and compared with data at lower energies. The contribution of beam and target diffractive dissociation and double Pomeron exchange, and porperties of these reactions are discussed. [ABSTRACT FROM AUTHOR]

We present data on the flow of energy and charge in π p, K p and pp interactions at 250 GeV/c. The energy and charge flow in the beam c.m. hemisphere is analysed in terms of the cluster-invariant Bialas-Ochs-Stodolsky variable λ=cot θ/ E . The profile functions dQ/dλ and dE/dλ indicate a widening in p of jets between 32 and 250 GeV/c incident laboratory momentum, whereas the ratio dQ/dE is energy independent. The data are compared to μ p deep-inelastic scattering resutls and to expectations from the single string LUND model, the Dual Parton Model and the two-string LUND model (FRITIOF). [ABSTRACT FROM AUTHOR]

Forward-backward multiplicity correlations in σ, K p and pp collisions at 250 GeV/c ( $$\sqrt s $$ =22 GeV) are given for all charges and for the different charge combinations. The correlations are found to be caused predominantly by centrally produced particles. It is demonstrated that this result is an agreement with observations at the ISR and the CERN p $$\bar p$$ -Collider. The results are compared to expectations from LUND, DPM and FRITIOF Monte Carlo models and a geometrical picture relating correlations in hadron-hadron collisions to e e data in terms of impact parameters is tested. [ABSTRACT FROM AUTHOR]

Multiplicity distributions, observed in K interactions with Al and Au nuclei at 250 GeV/c incident momentum are presented. They are analyzed in the framework of multiple collisions of the incident particle inside a nucleus. The probability distribution of the number of grey tracks is well described by the model of Andersson et al., if a negative binomial distribution is assumed for the distribution of the number of grey protons produced per elementary collision instead of the usual geometrical distribution. The analysis of the average and dispersion of the charge multiplicity distribution supports the validity of the multiple collision model, including results on correlations between forward and backward multiplicities. [ABSTRACT FROM AUTHOR]

A detailed analysis of the inclusive production of the vector mesons φ, K(892) $$\bar K*^0 (892),\rho ^{ + ,0} ,\omega $$ and the tensor mesons K)(1430) and f(1270) in K p interactions at 250 GeV/c is presented The data are compared with results at lower energies and with various quark-parton models. The production of ρ, K(892) and $$\bar K*^0 (892)$$ increases at the same rate as a function of s, is concentrated in the central region and is not reproduced by the models. Production of the tensor mesons f(1270) and K(1340) is suppressed relative to ρ and K(892) by a factor of about 3. [ABSTRACT FROM AUTHOR]

Results on inclusive single diffraction dissociation in π and K p interactions at 250 GeV/c are presented for excited masses up to ≃9 GeV. Total and topological cross sections for meson and proton diffraction are determined and their energy dependence is studied. For meson diffraction, hadronization of the diffractive system is well described by a MC model with $$q\bar q$$ -Lund fragmentation and is found to be similar to hadronization in e e , annihilation in terms of thrust and mean charged multiplicity. Fireball-like decay models can be excluded from an elongation of the meson system along the beam-pomeron axis. [ABSTRACT FROM AUTHOR]

New results are reported on inclusive charged particle production in K p, π p and pp collisions at 250 GeV/c. Inclusive longitudinal and transverse momentum spectra of positively and negatively charged particles are presented. Scaling in the fragmentation regions and scaling violation in the central c.m. region is investigated in detail. The topological pseudo-rapidity densities are shown to scale in the c.m. energy range from 22 to 900 GeV. [ABSTRACT FROM AUTHOR]

Two-pion correlations are studied for pions of like charge in K p and π p collisions at 250 GeV/c. An enhanced production is observed at small momentum difference and is attributed to Bose-Einstein interference between identical particles. A systematic study is presented on the influence of parametrization and reference sample. Interpreted in terms of the Kopylov-Podgoretskii parametrization a size of the emitting region r≈1.4 fm is found. The Lorentz invariant parametrization of Goldhaber gives r≈0.8 fm. With fixed parametrization, similarity is found for hadronhadron, e e and lepton-hadron collisions. No multiplicity or angular dependence is found at our energy. [ABSTRACT FROM AUTHOR]

The charged particle multiplicity distribution has been studied for non-single-diffractive π p and pp collisions at $$\sqrt s = 22$$ GeV, for full phase space as well as for intervals in rapidity, azimuthal angle and transverse momentum. In general, the multiplicity distribution is well described by a negative binomial. From comparison of the distribution for negative or positive particles to that of all charged particles, cascading is favoured as an interpretation over stimulated emission. Interesting consequences follow from a comparison of our results to those at collider energies and to e e data at comparable energy. Furthermore, evidence is given that the multiplicity distribution is not exactly of negative binomial type in every (connected or disconnected) phase space region. [ABSTRACT FROM AUTHOR]

Data are presented on inclusive π production in the forward c.m. hemisphere ( x>0.025) in π p, K p and pp interactions at 250 GeV/c. These data are compared to results at other energies and interpreted in terms of quark-parton models. [ABSTRACT FROM AUTHOR]

Cross sections and charged multiplicity distributions for π p, K p and pp interactions at 250 GeV/c are presented and compared to each other as well as to earlier (for π p and K p lower energy) data. Consistently, the meson-proton ( M p) data have narrower multiplicity distributions and higher average multiplicity than pp data. Up to our energy, generalized KNO functions describe the energy dependence of the shape of the multiplity distribution with one parameter for M p and one for pp collisions. If interpreted in terms of negative binomials, the parameter 1/ k tends to be slightly lower for M p than for pp data. For both types of hadron-hadron collision, 1/ k is larger than for e e and lp collisions. [ABSTRACT FROM AUTHOR]

Using data obtained with EHS equipped with the Rapid Cycling Bubble Chamber (RCBC) exposed to a proton beam of 360 GeV/c, we calculate topological cross sections. We present in great detail the procedure and the techniques used to correct raw data. Finally, we give multiplicity moments and multiplicity correlations and we compare the values obtained in our experiment, together with data at other energies, with different models. [ABSTRACT FROM AUTHOR]

In an experiment with the 30-inch Hybrid Spectrometer at Fermilab we have obtained the inclusive and semi-inclusive production cross sections of the ϱ meson using a conventional background subtraction technique. Production cross sections for the ϱ are derived as a function of the Feynman scaling variable x, and the transverse variables p and E=( p+ M). The longitudinal distributions are compared with the (1−x) dependence of the proton and meson valence quark structure functions, using various forms of recombination and fragmentation models. The transverse distributions are compared with thermodynamic models. We give density matrix elements for the ϱ production from pions in the extreme forward region. [ABSTRACT FROM AUTHOR]

The effect of 6 weeks' streptozotocin (STZ)-induced (70 mg/kg) diabetes and aminoguanidine (AG) treatment (50 mg/kg s.c. or 250-750 mg/l given in drinking water) on arteriolar reactivity to vasoactive substances was investigated in conscious rats. Studies were performed in untreated control rats (n = 13), STZ-induced diabetic rats (n = 11), AG-treated control rats (n = 12), and AG-treated diabetic rats (n = 12). Rats were provided with a dorsal microcirculatory chamber that allowed intravital microscopy of striated muscle arterioles of varying diameter (A1, large; A2, intermediate; and A3, small arterioles) in conscious animals. The mean arterial pressure (MAP) and arteriolar diameter responses to intravenous infusion of the following drugs were examined: the endothelium-dependent vasodilator acetylcholine (ACh; 3, 10, and 30 microg x kg(-1) x min(-1)), the potassium-channel opener levcromakalim (LC; 30 microg/kg), and the vasoconstrictor agents ANG II (0.1 and 0.3 microg x kg(-1) x min(-1)) and norepinephrine (NE; 0.2, 0.6, and 2.0 microg x kg(-1) x min(-1)). Baseline MAP was lower in both diabetic groups versus the nondiabetic groups (P < 0.05). AG treatment had no influence on baseline MAP. The absolute change in MAP after drug infusion tended to be lower in the diabetic rats than in their nondiabetic littermates. Arteriolar vasodilatory responses to ACh and LC were attenuated in the diabetic animals (1 +/- 7 vs. 19 +/- 7% [P < 0.05] and 7 +/- 3 vs. 34 +/- 8% [P < 0.01] in A2, respectively). AG treatment of diabetic animals did not prevent the development of this disturbance. Vasoconstrictor responses were not influenced by the diabetic state. In the intermediate arterioles of AG-treated control rats, a hyperresponse was observed after ANG II infusion (-10 +/- 2 vs. -2 +/- 2%; P < 0.05) and a hyporesponse was observed after ACh and LC infusion (2 +/- 3 and 15 +/- 6%, respectively; P < 0.05 vs. untreated control rats). These data indicate that 6 weeks of experimental diabetes is associated with a decreased endothelium-dependent and -independent vasodilatation. AG treatment had no beneficial effect on this disturbance. [ABSTRACT FROM AUTHOR]