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The temporal evolution of the current-driven electrostatic ion–cyclotron (CDEIC) instability is investigated in the presence of a transverse dc electric field in a collisional magnetized plasma. It was found that the inclusion of a transverse dc electric field in addition to the magnetic field changes the dispersion characteristics of the ion cyclotron waves. The growth rate of the instability increases with the mode frequency and has the largest value at the mode frequencies 43 kHz (for ω≫kzvte) and 7.53 kHz (for kzvti≪ω≪kzvte) when the electron drift velocity is less than the critical value for the CDEIC instability. The growth rate also increases with the guide magnetic field and has the largest value at the magnetic fields 1.0 kG (kyρi∼0.35) for ω≫kzvte and 0.1 kG (kyρi∼0.2) for kzvti≪ω≪kzvte. The growth rate is a sensitive function of electron collision frequency. The results of the theory are applied to explain some of the experimental observations of Koepke et al. [IEEE Trans. Plasma Sci. 20, 631 (...

An ion beam propagating through a magnetized dusty plasma cylinder drives electrostatic dust ion cyclotron waves to instability via Cerenkov interaction. The growth rate of the instability increases with the relative density δ (=n0i/n0e) of negatively charged dust. The growth rate scales as the one-third power of the beam density. The frequency of the unstable wave also increases with the relative density δ of negatively charged dust. The results of the theory are applied to explain some of the experimental observations of Barkan et al. [Planet. Space Sci. 43, 905 (1995)].

A density-modulated electron beam propagating through a plasma cylinder drives electrostatic lower hybrid waves to instability via Cerenkov interaction. The lower hybrid wave instability has the largest growth rate γ when the frequency and wave number of the modulation are comparable to that of the unstable wave. The growth rate of the instability increases with the modulation index Δ and is maximized for Δ=1. For Δ=0, γ turns out to be ∼0.43×107 sec−1. The growth rate scales as the one-third power of the beam density. The real frequency of the unstable wave increases as almost the square root of the beam voltage. The results of the theory are applied to explain some of the experimental observations of Chang [Phys. Rev. Lett. 35, 285 (1975)].

Acceleration and heating of a relativistic electron beam by cascading nonlinear Landau damping involving three or four intense electromagnetic waves in a plasma are studied theoretically based on kinetic wave equations and transport equations derived from relativistic Vlasov–Maxwell equations. Three or four electromagnetic waves excite successively two or three nonresonant beat‐wave‐driven relativistic electron plasma waves with a phase velocity near the speed of light [vp=c(1−γ−2p)1/2, γp=ω/ωpe]. Three beat waves interact nonlinearly with the electron beam and accelerate it to a highly relativistic energy γpmec2 more effectively than by the usual nonlinear Landau damping of two electromagnetic waves. It is proved that the electron beam can be accelerated to more highly relativistic energy in the plasma whose electron density decreases temporally with an appropriate rate because of the temporal increase of γp.

We purified and characterized a novel axonal growth-related molecule, neurin-1, which is anchored to the surface membrane via a phosphatidylinositol (PI) linkage. This molecule was detected by a combination of phosphatidylinositol-specific phospholipase C (PI-PLC) treatment from detergent-soluble mouse brain membranes and subsequent Western blot analysis with monoclonal antibody (MAb 2A). Neurin-1 is immunologically distinct from other known axonal growth associated surface glycoproteins. In immunoblots of embryonic mouse brain membrane, the MAb 2A recognized a single band at approximately 68 kDa, and showed that neurin-1 is mainly associated with fiber-containing regions of developing embryonic mouse brain. Expression is immunohistochemically similar to that of cell adhesion molecule L1, but in comparison, neurin-1 appears somewhat later. Late in embryonic development, neurin-1 appeared to be more stage- and region-specific. Its precise localization at the neural cell surface membranes was confirmed by immuno-electron microscopy using labeled and cultured live nerve cells. Neurin-1 was found only on the surface of the axon and growth cone. Neurin-1, otherwise termed PI anchor protein, corresponds closely in function to the other PI-anchored cell adhesion molecules. Anti-neurin-1 antibody (MAb 2A), however, perturbs the axonal growth and neural cell migration from the astrocyte feeder layer cultures. These results suggest that neurin-1 is one of the important cell surface molecules mediated in the neuron and glial cell interaction.

In the present paper, the parametric decay instability of an extraordinary electromagnetic wave (X-wave) into an electron Bernstein wave (EBW) and an electrostatic whistler wave (W-wave) has been studied. Expressions are derived for homogeneous threshold, growth rate, and convective threshold for this instability. The relevance of the present parametric process has been pointed out to explain the generation of whistler mode radiations in the SL-2 experiment, ionospheric modification experiment, in the polar cusp region of the magnetosphere, as well as during intense electron cyclotron resonance heating in the MTX tokamak.

We previously suggested that activation of the protein kinase C-mediated contractile system may participate in the occurrence of chronic cerebral vasospasm. In the present study, we compared segments of normal beagle basilar arteries in vitro with segments of arteries undergoing chronic vasospasm to determine the responsiveness to various agonists such as serotonin, prostaglandin F2 alpha, and phorbol 12,13-diacetate as well as to external Ca2+. We also compared the effects of W-7 (a calmodulin inhibitor), nicardipine (a calcium channel blocker), and H-7 (a protein kinase C inhibitor) on the spontaneous tonus of arterial segments stabilized at a resting tension of 3 g. Compared with normal segments, the responsiveness to each agonist in segments undergoing vasospasm was essentially unchanged whereas the the responsiveness to external Ca2+ was significantly decreased (p less than 0.001). In segments undergoing vasospasm the decrease in resting tension induced by W-7 was markedly diminished (p less than 0.01), that induced by nicardipine was unchanged, and that induced by H-7 was significantly increased (p less than 0.01). Our results indicate that spontaneous tonus due to activation of the protein kinase C system is significantly augmented in segments undergoing vasospasm. Thus this system, rather than the Ca2+/calmodulin system, appears to play a major role in the occurrence of chronic vasospasm.

1. Catecholamines were determined by HPLC in honeybee brains using automatized extraction and on-line detection with an electrochemical detector. 2. This method has high sensitivity in the range of fmols. Thus, catechols can be measured in single brains as well as in parts of brains. 3. The comparison of brains of worker bees and queens shows a caste-specific content of eatecholamine concentrations in worker bees and queens. 4. The amount of norepinephrine and dopamine are higher in queens than in worker bees. 5. The differences are not caused by the different size of the respective brains, but reflect a difference in the two female castes.

In recent years, with the development of "Digital Archives" technology, preserving historical assets including cultural artifacts as digital data has started to become possible. However, this method is still in the midst of development, therefore the traditional method of creating data from photos and text is still preferred. When we consider "Digital Archives" as an integrated technology of collecting, processing, preserving and using data, the skill of collecting data is comparatively underdeveloped. This technology proposed in this report is another way to collect data, and we hope it will enhance the quality of "Digital Archives" of such fields as fine arts and crafts like Japanese swords.

Publisher Summary This chapter reports experimental results on ion acoustic waves in dusty plasma. It is found that the phase velocity of the ion acoustic fast mode increases with an increasing the concentration of the negatively charged dust grains, ɛ while the wave damping decreases with increasing ɛ. An ion beam propagating through a magnetized dusty plasma cylinder destabilizes electrostatic dust ion acoustic waves. The chapter discusses a nonlocal theory of this process. According to the results, the fluctuations of the dust grain charge are found to be a source of wave damping or growth.

We purified and characterized a novel axonal growth-related molecule, neurin-1, which is anchored to the surface membrane via a phosphatidylinositol (PI) linkage. This molecule was detected by a combination of phosphatidylinositol-specific phospholipase C (PI-PLC) treatment from detergent-soluble mouse brain membranes and subsequent Western blot analysis with monoclonal antibody (MAb 2A). Neurin-1 is immunologically distinct from other known axonal growth associated surface glycoproteins. In immunoblots of embryonic mouse brain membrane, the MAb 2A recognized a single band at approximately 68 kDa, and showed that neurin-1 is mainly associated with fiber-containing regions of developing embryonic mouse brain. Expression is immunohistochemically similar to that of cell adhesion molecule L1, but in comparison, neurin-1 appears somewhat later. Late in embryonic development, neurin-1 appeared to be more stage- and region-specific. Its precise localization at the neural cell surface membranes was confirmed by immuno-electron microscopy using labeled and cultured live nerve cells. Neurin-1 was found only on the surface of the axon and growth cone. Neurin-1, otherwise termed PI anchor protein, corresponds closely in function to the other PI-anchored cell adhesion molecules. Anti-neurin-1 antibody (MAb 2A), however, perturbs the axonal growth and neural cell migration from the astrocyte feeder layer cultures. These results suggest that neurin-1 is one of the important cell surface molecules mediated in the neuron and glial cell interaction.

Age-related correlation of impaired plasticity of neurons (biochemical and biophysical aspects) and behavioral alterations were investigated in young (3.5 months) and extremely aged (approximately 40 months) female Wistar rats. Age-dependent significant differences in second messenger (cAMP and Ins (1,4,5)P3) concentration and signal transduction via muscarinic and dopaminergic receptors were found. The results point to the specifically impaired coupling between dopamine D1 receptor and GS protein, which underlies normal brain aging. However, cholinergic neurotransmission may be modulated at another level in extremely aged rats. Thus, it appears that the site of affection in coupling of receptor and G protein and/or G protein-dependent signal transduction in aging cannot be generalized. This indicates that alterations in the coupling of signal transduction depend on diverse neurotransmitter receptors with advanced age. The age-dependent alterations in the cAMP and PI signal pathways could be due to changes in the physical properties of the membranes. To support this hypothesis, age-dependent changes in the physical state and the biochemical composition of synaptosomal membranes from the cortex, cerebellum, and striatum were examined by measuring the steady-state fluorescence amisotropy of the membrane probes 1,6-diphenyl-1,3,5-hexatriene (DPH), trimethylammonium-DPH (TMA-DPH), and trimethylammoniumpropyl-DPH (TMAP-DPH). Significant differences in the physical properties of the synaptosomal membranes existed between young and very aged rats, expressed by a higher anisotropy in the 40-month-old rat brain tissue. The changes in the physical properties of the membranes were in line with the determined age-dependent alterations in the chemical composition, e.g., the increase in cholesterol content of the aged membranes.

Acceleration and heating of a relativistic electron beam induced by cascading nonlinear Landau damping involving three or four intense electromagnetic waves in a plasma are investigated theoretically by using relativistic Vlasov‐Maxwell equations. It is proved that a relativistic electron beam can be accelerated more effectively by the cascading nonlinear Landau damping than by usual process of two electromagnetic waves.

The process of the plasma discharge due to an electron beam is experimentally investigated. A pulse (∼540 μs) of an electron beam (0.5–1.5 keV, ≤20 mA) is injected into argon gas (5×10−5–5×10−4 Torr) in a magnetic field (50–300 G). The discharge based on a gas break down occurs cascade‐likely in time. The gas beak down with some steps is explained by the two stream instability of an electron beam‐plasma system, from the observation of the temporal evolution of the frequency spectra (0–3.0 GHz) of the instability and the measurement of the temporal plasma density and temperature.

The possible age-related involvement of two different signal transduction pathways in the rat CNS was investigated. In the phosphytidyl inostiol (PI) response, higher phospholipase-C (PL-C) activity and drastically higher (almost 2.5-fold) inositol (1,4,5)trisphosphate (Ins(1,4,5) P(3)) concentration in the corpus striatum (caudate-putamen) of extremely old (approximately 40 months) female Wistar rats in comparison to young adult (approximately 3.5 months) rats were observed. In the adenosine 3':5'-cyclic monophosphate (cAMP) cascade, a significantly higher endogenus cAMP level and a significant decline of the adenylate cyclase (AC, ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1.) activity were observed in striatal tissue from young rats in comparison with aged rats. Binding saturation experiments with [(3)H]SCH 23390 at the dopamine (DA) D(1) receptor (D(1)) and [(3)H]spiperone at the DA D(2) receptor (D(2)) revealed no change in the affinity (K(d)) but a significant decrease in the density (B(max)) of D(1) (-31%, p0.005) and of D(2) (-22%, p0.05), respectively, in the aged versus young striata. DA seems to slightly inhibit total inositol phosphate formation and this effect was antagonized by (-)-sulpiride. A significant decrease (p0.05) in the AC activity stimulated by 10 muM DA in the senescent compared to the young animals was monitored. Apparently, the age-related decline of the AC activity was independent of changes of G(S) and G(i) activity.

The possible anti-amnesic effects of a dibenzoxazepine derivative, BY-1949 (3-methoxy-11-methyldibenz[b,f] [1, 4] oxazepine-8-carboxylate), were examined using the three learning paradigms. In the one-trial passive avoidance task in mice, BY-1949 (1-30 mg/kg, po) and aniracetam (3-30 mg/kg, po) reversed the shortening of the response latency in the retention test produced by exposure to 100% CO2 immediately after the acquisition trial. In the two-way active avoidance task in rats, BY-1949 (10, 30 mg/kg, po) reversed the decreased avoidance rate produced by the hypoxia treatment (5% O2:95% N2). In the radial-arm maze task in rats, BY-1949 (10 mg/kg, po) and aniracetam (10, 30 mg/kg, po) improved the impaired correct choices induced by scopolamine (0.25 mg/kg, ip). These results suggest that BY-1949, as well as aniracetam, exerts some improvement effects on experimental amnesia.

The authors examined the parametric decay instability of the linearly unstable electrostatic ion cyclotron wave in an ion beam-plasma system which decays to an ion acoustic wave and a linearly stable electrostatic ion cyclotron wave. They have derived a set of equations which represent this mechanism, and obtained numerical results of the temporal evolution of the amplitude of the related wave and distortions of the velocity distribution function. The beam distortion begins to occur at the stage of linear instability and becomes large at the stage of nonlinear instability. Ion heating of the plasma occurs only at the stage of nonlinear instability. These large distortions of the ion beam and ion heating of the plasma are caused by the deceleration of the ion beam.

Since chronic alcoholics may accompany with asymmetric septal hypertrophy (ASH), the purpose of this study was to find the difference in cardiac function of such cases from the patients with hypertrophic cardiomyopathy. Ninety-seven alcoholic patients (59 non-cirrhotics and 38 cirrhotics) were examined by non-invasive methods including two-dimensional echocardiography and dye dilution method, and these data were compared with those of 16 normal subjects and 26 patients with hypertrophic cardiomyopathy. The results were as follows: Interventricular septal thickness of more than 12 mm was observed in 25.4% of the non-cirrhotics and 28.9% of the cirrhotics. Furthermore, ASH was present in 23.7% of the former and 18.4% of the latter, when ASH was defined as the septal to posterior wall ratio greater than 1.3 with the interventricular septal thickness greater than or equal to 12 mm. In 66.7% of the chronic alcoholics with ASH, hypertrophy was predominantly located in the septum, however 53.8% of the patients with hypertrophic cardiomyopathy had ASH in association with the thickened left ventricular posterior wall. In 21 chronic alcoholics with ASH, ejection indices such as ejection fraction and mean VCF were moderately increased, although scattered widely, as compared with those of the normal subjects. Latent reduced ventricular function compensated by sympathetic overactivity was postulated based on left ventricular performance maintained normally as indicated by a decrease of end-systolic wall stress. Several possible factors including hypertension, catecholamine and metabolic abnormalities were analyzed to explain the genesis of ASH in chronic alcoholics, but the true etiology remained unknown. In conclusion, ASH associated with chronic alcoholism is a type characteristic of alcoholic cardiomyopathy, and seems to belong to a clinical entity different from hypertrophic cardiomyopathy from a standpoint of clinical symptoms, age and the pattern of left ventricular hypertrophy.

Local injections of small quantities (≤10 nl) of drugs reveal a selective facilitatory action of octopamine and noradrenaline, and an inhibitory action of 5-HT and dopamine on particular associative and non-associative components of olfactory learning and memory in bees. It is concluded that the mushroom bodies are the neuropiles in which the antagonistic effects of octopamine and 5-HT act on olfactory memory. A single conditioning trial proceeding or following drug injection enables the distinction of whether a drug affects memory formation or memory recall. Dopamine reduces selectively memory recall, octopamine facilitates both memory recall and formation, and 5-HT also inhibits both memory recall and formation.

Experimental results are presented for a repelling of electron beam drifting along an increasing magnetic field by the local electron cyclotron resonance with the non-uniform static magnetic and high frequency fields.

Experimental results are presented for a repelling and a trapping of plasma beam in a mirror field by the local electron cyclotron resonance with the non-uniform static magnetic and electromagnetic fields.

The nonlinear Landau damping and growth of electrostatic waves in an electron beam‐plasma system in a magnetic field has been observed experimentally. The space charge wave of the beam decays into the Trivelpiece mode, which is amplified exponentially by increasing the amplitude of the pump wave.