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Alfvénic turbulent cascade perpendicular and parallel to the background magnetic field is studied accounting for anisotropic dispersive effects and turbulent intermittency. The perpendicular dispersion and intermittency make the perpendicular-wave-number magnetic spectra steeper and speed up production of high ion cyclotron frequencies by the turbulent cascade. On the contrary, the parallel dispersion makes the spectra flatter and decelerate the frequency cascade above the ion cyclotron frequency. Competition of these factors results in spectral indices distributed in the interval [-2, -3], where -2 is the index of high-frequency space-filling turbulence and -3 is the index of low-frequency intermittent turbulence formed by tube-like fluctuations. Spectra of fully intermittent turbulence fill a narrower range of spectral indices [-7/3, -3], which almost coincides with the range of indexes measured in the solar wind. This suggests that the kinetic-scale turbulent spectra are mainly shaped by the dispersion and intermittency. A small mismatch with measured indexes of about 0.1 can be associated with damping effects not studied here. Dispersion and intermittent effects are included in an Alfvenic turbulence modelSpectra of fully intermittent turbulence fill a narrower range of spectral indices [-7/3, -3]The kinetic Alfven wave can reach the ion cyclotron frequency through the turbulent cascade

Neutron production from a thin deuterium–tritium (D–T) foil irradiated by two intense femtosecond laser pulses from opposite sides with zero phase difference is studied analytically and numerically. For the interaction of a laser pulse of amplitude $a=7$, focal area 100 $\mu$m$^2$ and areal density $4.4\times 10^{18}$ cm$^{-2}$ with a D–T plasma foil, about $1.17\times 10^{21}$ neutron s$^{-1}$ can be obtained, much more than from other methods. The profiles of the ion and electron densities are also calculated.

The effect of density and size of dust grains on the electron energy distribution function (EEDF) in low-temperature complex plasmas is studied. It is found that the EEDF depends strongly on the dust density and size. The behavior of the electron temperature can differ significantly from that of a pristine plasma. For low-pressure argon glow discharge, the Druyvesteyn-like EEDF often found in pristine plasmas can become nearly Maxwellian if the dust density and/or sizes are large. One can thus control the plasma parameters by the dust grains.

Objectives.The objectives of this study were to evaluate the use of laparoscopic ultrasonography (USG) in combination with laparoscopic pelvic lymphadenectomy in the management of patients with cervical carcinoma.Methods.A technique for detecting pelvic and para-aortic lymph node metastases through laparoscopic USG was developed. Laparoscopic USG was done prior to pelvic lymphadenectomy performed either laparoscopically or by laparotomy. Laparoscopic USG findings were compared with pathologic findings.Results.The sensitivity and specificity of laparoscopic USG in detecting pelvic lymph node metastases were 91 and 100%, respectively. Metastatic pelvic lymph nodes could be completely removed through laparoscopes in 7 of 11 patients, with no complications.Conclusion.Laparoscopic USG is highly sensitive in detecting metastatic pelvic lymph nodes. Detection and removal of metastatic pelvic lymph nodes laparoscopically allow quick recovery from the operation and early commencement of radiotherapy.

Assay methods for chitinase, ß-glucanase and a-glucanase in the presence of the osmotic stabilizers used in fungal protoplast liberation were developed. Chitinase activity with an inorganic osmotic stabilizer system was in the order of NO3-, Cl->SO42->PO43- and Na+, K+>Ca2+, Mg2+. Monovalent anion salts with monovalent cations improved chitinase activity, whereas divalent and trivalent anion and cation salts caused appreciable inhibition; phosphate salts induced very serious inhibition. These phenomena suggest that a suitable electrical state is required for optimal chitinase activity. MgSO4, KCl and NH4Cl were equally efficient as stabilizers for protoplast liberation, although they had different effects on chitinase activity. a-glucanase was inhibited more by sucrose than by mannitol and sorbitol; ß-glucanase was relatively stable to both organic and inorganic osmotic stabilizers. As chitin is the major component of the fungal cell wall, chitinase is thought to be more important for protoplast liberation than are ß-glucanase and a-glucanase.

Mathematically exact solutions describing propagating waves are constructed for a cold magnetized plasma bounded by a rigid cylindrical dielectric. Possible particle sources and sinks due to chemical reactions are allowed. It is found that the volume waves can be either amplified or damped because of their density dependence, while the surface waves are unaffected by the sources and sinks.

Adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] activity of purified secretory vesicle membranes from the adrenal medulla is inhibited by I-isoproterenol and I-epinephrine, as well as by nerve growth factor (NGF). The effect of these agents was found to be dose-dependent and, in the case of the catecholamines, saturable. NGF was active at concentrations as low as 10(-8) M. Oxidized NGF was only minimally active, and insulin was completely inactive. Neither dopamine nor phenylephrine had activity. Inhibition of cyclase by either isoproterenol or epinephrine was blocked by I-propranolol, a specific beta-antagonist, but propranolol by itself had no effect on adenylate cyclase activity. The data indicate that the secretory vesicle membrane has beta-adrenergic receptors coupled to the adenylate cyclase. Propranolol was also found to block the NGF-induced inhibition of cyclase. We conclude that the granule membrane has beta-adrenergic receptors as well as NGF-reactive sites, and that the two may be functionally linked.

The nonlinear interaction of the external magnetic field-aligned circularly polarized electro-magnetic radiation with a cold electron-positron plasma is considered. A set of nonlinear equations is derived describing the coupling of the radiation with cold electrostatic oscillations. Modulational instabilities and wave localization are discussed.

The decay of a high-frequency wave into a scattered and an electrostatic wave is investigated for a homogeneous magnetized plasma. For wave propagation in arbitrary directions, an equation for the scattered wave is obtained accounting for the effect of the non-linear current density produced by the three-wave interaction process. As an illustration, the propagation of electromagnetic waves perpendicular to the external magnetic field is considered. The growth rates and thresholds for the stimulated scattering and modulational instabilities are obtained. The influence of a weak inhomogeneity is also considered.

It is shown that a fast ion-acoustic wave can decay into another ion-acoustic wave and a whistler wave. The results are applied to interpret wave spectra measurements in the foreshock region of the Earth's bowshock.

The linear and nonlinear properties of the modified electron thermal waves are studied. The waves are of acoustic nature and can exist without significant damping in a two-electron temperature plasma. Nonlinearly, they can form propagating localized regions with depletion of hot electrons. Practical applications of our results to space plasmas are discussed.

A set of coupled nonlinear equations is derived which describes the coupling of the vorticity and the external-field aligned flow of a strongly magnetized rotating electron-positron plasma. The possibility of dipole vortex formation is discussed.

The radiative thermal instability is investigated taking into account finite-ß, or electromagnetic, effects. The two-fluid model for magnetized plasmas together with the Maxwell equations are used to derive a general dispersion relation valid for compressional perturbations with frequency below the electron-cyclotron frequency. The growth rates of the radiative thermal instabilities involving fast magnetosonic flute-like and low-frequency hydromagnetic perturbations are presented.

A set of coupled nonlinear differential equations which govern the dynamics of finite amplitude electromagnetic waves in the presence of an external current gradient in a magnetized electron-positron plasma has been derived. It is shown that the current gradient can make shear Alfvén-like waves unstable. A quasi-stationary solution of the mode-coupling equations is the well-localized dipole vortex. Application of our results to plasma transport in the pulsar magnetosphere is briefly discussed.

Equations governing the coupling of the scalar and vector potentials for a resistive electron-positron plasma in a strong magnetic field are derived. It is shown that in the presence of magnetic shear, a tearing instability may occur. The latter can lead to magnetic field line reconnection and the formation of magnetic islands which could affect the dynamics of the pulsar magnetosphere.

It is shown that in a strongly magnetized relativistic electron-positron plasma, strongly localized large amplitude circularly polarized electromagnetic wave pulses exist. The localization is due to relativistic mass variation as well as ponderomotive force effects. Three types of pulses are found analytically: the sharply spiked pulse in a strongly magnetized cold plasma, the smooth pulse in a week magnetized warm plasma, and the moderately spiked pulse for a weakly magnetized cold plasma. The physical mechanisms giving rise to these pulses are distinct for each case. Possible implications of our investigation to pulsar radiation are discussed.

Ordered structures as well as chaotic motion of the magnetic electron drift vortex (MEDV) mode in a unmagnetized nonuniform plasma are discussed. In the collisionless limit, the nonlinear MEDV waves can self-organize into dipolar vortices or vortex chains. The latter exist in the regime where dipolar vortices are forbidden. When dissipation is included, the governing equations for the MEDV mode can be cast into the form of the Lorenz equations, so that chaotic solutions can exist.

Fluid theory is used to investigate nonlinear potential structures in an inhomogeneous magnetized dusty plasma. Dipolar-vortex and modified convective cell structures are shown to exist.

It is shown that relativistic electron plasma waves can propagate as quasi-stationary nonlinear waves as well as solitary pulses.

We show analytically that the nonlinear coupling of a large amplitude electromagnetic wave with finite amplitude ion fluctuations leads to filamentation. The latter consists of striations of the electromagnetic radiation trapped in depressions of the plasma density. The filamentation is found to be either standing or moving normal to the direction of the incoming radiation. Criteria for the existence of localized filaments are obtained. Small amplitude results are discussed.

Nerve growth factor (NGF) produces a several-fold increase in the cyclic AMP concentration in rat superior cervical ganglia in organ culture within 5 min. An increase can be seen with as little as 40 ng/ml of NGF. Oxidized NGF is without effect. The increase in the cAMP concentration produced by NGF is prevented by the addition of antiserum to NGF.

We report here a case of fatal Penicillium citrinum infection. The patient, who suffered from acute myeloid leukemia, developed signs and symptoms typical of fungal pneumonia and pericardial tamponade after undergoing standard induction chemotherapy. Despite attaining complete remission of her leukemia, the patient succumbed 8 weeks after presentation. At autopsy, multiple nodular cavitary pulmonary lesions with invasion by fungal hyphae were found. Pericardial and lung tissue obtained at autopsy grew P. citrinum, a fungus ubiquitous in the environment but seldom reported as a pathogen. The microbiological findings were consistent with the histopathological features and confirmed this as a case of true P. citrinum infection causing fatal pulmonary and pericardial complications in an immunocompromised host.