Study of nerve fibers nature reinforcing duodenal contractions by electrical stimulation of sympathetic nerve

The subject of the article is to investigate the mechanism of increased reactions by electrical stimulation of the sympathetic nerve. Materials and methods: Experiments on dogs have shown that stimulant reactions during blockade of a-adrenergic by phentolamine and (3-adrenergic receptors with propranolol were completely eliminated by lizer-gol —the blocker of 5-HT12-receptors. Results: Infusion of lizergol did not influence on duodenal motor activity and the function of the vagus nerve. Conclusion: Effector neuron is found out to be serotonergic and its action is provided by 5-HT1 2 receptor

Factorizing the hard and soft spectator scattering contributions for the nucleon form factor F_1 at large Q^2

We investigate the soft spectator scattering contribution for the FF $F_{1}$. We focus our attention on factorization of the hard-collinear scale $\sim Q\Lambda$ corresponding to transition from SCET-I to SCET-II. We compute the leading order jet functions and find that the convolution integrals over the soft fractions are logarithmically divergent. This divergency is the consequence of the boost invariance and does not depend on the model of the soft correlation function describing the soft spectator quarks. Using as example a two-loop diagram we demonstrated that such a divergency corresponds to the overlap of the soft and collinear regions. As a result one obtains large rapidity logarithm which must be included in the correct factorization formalism. We conclude that a consistent description of the factorization for $F_{1}$ implies the end-point collinear divergencies in the hard and soft spectator contributions, i.e. convolution integrals with respect to collinear fractions are not well-defined. Such scenario can only be realized when the twist-3 nucleon distribution amplitude has specific end-point behavior which differs from one expected from the evolution of the nucleon distribution amplitude. Such behavior leads to the violation of the collinear factorization for the hard spectator scattering contribution. We suggest that the soft spectator scattering and chiral symmetry breaking provide the mechanism responsible for the violation of collinear factorization in case of form factor $F_{1}$.Comment: 25 pages, 6 figures, text is improved, few typos corrected, one figure added, statement about end-point behavior of the nucleon DA is formulated more accuratel

High statistic measurement of the K- -> pi0 e- nu decay form-factors

The decay K- -> pi0 e- nu is studied using in-flight decays detected with the ISTRA+ spectrometer. About 920K events are collected for the analysis. The lambda+ slope parameter of the decay form-factor f+(t) in the linear approximation (average slope) is measured: lambda+(lin)= 0.02774 +- 0.00047(stat) +- 0.00032(syst). The quadratic contribution to the form-factor was estimated to be lambda'+ = 0.00084 +- 0.00027(stat) +- 0.00031(syst). The linear slope, which has a meaning of df+(t)/dt|_{t=0} for this fit, is lambda+ = 0.02324 +- 0.00152(stat) +- 0.00032(syst). The limits on possible tensor and scalar couplings are derived: f_{T}/f_{+}(0)=-0.012 +- 0.021(stat) +- 0.011$(syst), f_{S}/f_{+}(0)=-0.0037^{+0.0066}_{-0.0056}(stat) +- 0.0041(syst).Comment: 11 pages, 8 figures. Accepted by Phys.Lett.

Участие холинергических и адренергических механизмов в реакциях желудка на введение экзогенного серотонина

This study is dedicated to investigation of serotoninergic structures that activate motility of the stomach. Experiments were performed on 94 Wistar rats under general anesthesia, mechanical ventilation, bilateral vagotomy and transection of both glossopharyngeal nerves. Mechanical activity of the stomach was recorded during serotonin adipanate infusion to intact animals and on the background of the ongoing actions of cholinergic and adrenergic antagonists. The blockade of adrenergic and cholinergic receptors does not prevent, but contrary, increase stimulatory effect of serotonin. β-adrenergic blockade increases the intensity of observed reactions almost up to 90%. Conclusion: both adrenergic and cholinergic mechanisms provide inhibitory pattern on serotoninergic structures that regulates motor function of the stomach.Работа посвящена изучению серотонинергических структур, усиливающих моторику желудка. Опыты поставили на 94 крысах в условиях хирургической стадии наркоза, ИВЛ, двухсторонней ваготомии и двухсторонней перерезки языкоглоточных нервов. Регистрировали механическую активность желудка на введение серотонина адипината у интактных животных и на фоне продолжающегося действия адрено- и холиноблокаторов. Установили, что блокада адрено- и холинорецепторов не только не препятствует, а напротив, способствует проявлению реакций желудка на серотонин, причем блокада β-адренорецепторов увеличивала выраженность стимуляторных эффектов желудка почти на 90%. Сделали вывод о том, что адренергические и холинергические механизмы препятствуют проявлению стимуляторных реакций серотонинореактивных структур на моторику желудка

Влияние экзогенного серотонина на усиление вагусных реакций толстой кишки

This study is dedicated to serotoninergic structures of the colon. Experiments were performed in 35 Chinchilla rabbits under general anesthesia, mechanical ventilation, bilateral vagotomy. Mechanical and electrical activity of the ascending colon was recorded during electrical stimulation of the peripheral part of the right n. vagi in intact animals and after serotonin adipate injection. It was found that serotonin potentiates vagal effects of the colon, but without effect on duration of reaction. Concluded that the serotoninergic structures of the colon are able to control the parasympathetic portion of the autonomic nervous system.Работа посвящена изучению серотонинергических структур толстой кишки. Опыты поставили на 35 кроликах: в условиях хирургической стадии наркоза, ИВЛ, двухсторонней ваготомии. Регистрировали механическую и электрическую активность восходящей ободочной кишки. В эксперименте раздражали периферический отрезок блуждающего нерва у интактных животных и на фоне продолжающегося действия серотонина адипината. Установили, что серотонин усиливает вагусные эффекты толстой кишки, не влияя при этом на продолжительность стимуляторных реакций. Сделали вывод о взаимодействии серотонинореактивных структур толстой кишки с парасимпатическим отделом вегетативной нервной системы

Expansion of bound state energies in powers of m/M and (1-m/M)

Elaborating on a previous letter, we use a new approach to compute energy levels of a non-relativistic bound-state of two constituents, with masses m and M, by systematic expansions - one in powers of m/M and another in powers of (1-m/M). Technical aspects of the calculations are described in detail. Theoretical predictions are given for O(alpha(Z*alpha)^5) radiative recoil and O((Z*alpha)^6) pure recoil corrections to the average energy shift and hyperfine splitting relevant for hydrogen, muonic hydrogen, and muonium.Comment: 9 pages, revte

Search for light pseudoscalar sgoldstino in K- decays

A search for the light pseudoscalar sgoldstino production in the three body K- decay K-->pipi0P has been performed with the ISTRA+ detector exposed to the 25 GeV negative secondary beam of the U70 proton synchrotron. No signal is seen. An upper limit for the branching ratio Br(K->pipi0P), at 90% confidence level, is found to be around 9*10**-6 in the effective mass m(P) range from 0 till 200 MeV, excluding the region near m(pi0) where it degrades to 3.5*10**-5.Comment: 10 pages, LATEX, 8 EPS figures, revised version, to be published in Phys.Lett.

Acute complicated anaerobic paraproctitis: a case from practice

Anaerobic paraproctitis is a life-threatening disease, accompanied by a high mortality rate, requiring absolutely innovative diagnostic and therapeutic approaches. The development of acute paraproctitis is brought about by a number of predisposing factors: weakening of the immune system due to concurrent acute or chronical infection, microcirculation disorders, gastrointestinal disorders, complications of hemorrhoids, fissures, cryptitis. Not infrequently acute paraproctitis is complicated by Fournier’s gangrene. Objectives. To describe the clinical case of acute anaerobic non-clostridial paraproctitis. Material and methods. The paper presents a patient with suspected anaerobic non-clostridial paraproctitis. Results. We managed to control the process. The patient was discharged in a satisfactory condition for the outpatient treatment. Conclusions. As a result of complex treatment of the patient with symptoms of acute anaerobic non-clostridial paraproctitis, including a wide dissection of purulent streaks and antibiotic therapy, it was possible to stop the given disease

Measurement of the Dalitz plot slope parameters for K- -> pi0 pi0 pi- decay using ISTRA+ detector

The Dalitz plot slope parameters g, h and k for the K- -> pi0 pi0 pi- decay have been measured using in-flight decays detected with the ISTRA+ setup operating in the 25 GeV negative secondary beam of the U-70 PS. About 252 K events with four-momenta measured for the pi- and four involved photons were used for the analysis. The values obtained g=0.627+/-0.004(stat)+/-0.010(syst), h=0.046+/-0.004(stat)+/-0.012(syst), k=0.001+/-0.001(stat)+/-0.002(syst) are consistent with the world averages dominated by K+ data, but have significantly smaller errors.Comment: LaTeX, 10 pages, 8 eps-figures, update of IHEP 2002-1