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The activity of four mycotoxins extracted from Beauveria bassiana, Paecilomyces fumosoroseus and Nomuraea rileyi and a bacterial exotoxin of Bacillus thuringiensis var. thuringiensis were assayed for activity on larvae of the greater wax moth and the gypsy moth. The procedure for toxin extraction was described and toxins were administered via. topical application and intrahemocoelic injection. Larvae of the wax moth showed higher mortality rates, and in general, high levels of toxicity were recorded in both species. Zusammenfassung Wirkungen von Mikroben-Toxinen auf die Larven des Schwammspinners und der grosen Wachsmotte Es wurde die Aktivitat der toxischen Extrakte von 4 Mikroorganismen: Beauveria bassiana, Paecilomyces fumoso-roseus, Nomuraea rileyi und Bacillus thuringiensis var. thuringiensis auf die Larven des Schwammspinners und der grosen Wachsmotte untersucht. Die Methodik der Toxin-Extraktion und der topikalen sowie intrahaemocoenalen Injektion der Toxine werden beschrieben. Die Larven der grosen Wachsmotte zeigten hohere Sterblichkeitsraten als jene des Schwammspinners. Allgemein wurde eine hohe Wirksamkeit der Toxine aller 4 Mikroorganismen gegenuber den Larven beider Schmetterlingsarten festgestellt.

The baker’s map, invented by Eberhard Hopf in 1937, is an intuitively accesible, two-dimensional chaos-generating discrete dynamical system. This map, which describes the transformation of an idealized two-dimensional dough by stretching, cutting and piling, is non-dissipative. Nevertheless the “x” variable is identical with the dissipative, one-dimensional Bernoulli-shift-generating map. The generalization proposed here takes up ideas of Yaacov Sinai in a modified form. It has a staircase-like shape, with every next step half as high as the preceding one. Each pair of neighboring elements exchanges an equal volume (area) during every iteration step in a scaled manner. Since the density of iterated points is constant, the thin tail (to the right, say) is visited only exponentially rarely. This observation already explains the map's main qualitative behavior: The “x” variable shows “flares”. The time series of this variable is closely analogous to that of a flaring-type dissipative dynamical system – like those recently described in an abstract economic model. An initial point starting its journey in the tale (or “antenna”, if we tilt the map upwards by 90 degrees) is predictably attracted by the broad left hand (bottom) part, in order to only very rarely venture out again to the tip. Yet whenever it does so, it thereby creates, with the top of a flare, a new “far-from-equilibrium” initial condition, in this reversible system. The system therefore qualifies as a discrete analogue to a far-from-equilibrium multiparticle Hamiltonian system. The height of the flare hereby corresponds to the momentary height of theHfunction of a gas. An observable which is even more closely related to the momentary negative entropy was recently described. Dependent on the numerical accuracy chosen, “Poincaré cycles” of two different types (periodic and nonperiodic) can be observed for the first time.

Epinephrine is known to produce insulin resistance, but the exact molecular mechanism involved is unknown. In the present study we have examined the levels and phosphorylation state of the insulin receptor and of insulin receptor substrate 1 (IRS-1), as well as the association between IRS-1 and phosphatidylinositol 3-kinase (PI 3-kinase) in the liver and muscle of rats treated with epinephrine. The results demonstrate a decrease in insulin-stimulated receptor and IRS-1 phosphorylation levels which was accompanied by a reduction in the association of IRS-1 with PI 3-kinasein vivo in liver and muscle of epinephrine treated rats. These data suggest that molecular post-receptor defects may explain some aspects of the insulin resistance induced by catecholamines.

In the present study we have examined the levels and phosphorylation state of the insulin receptor and insulin receptor substrate 1 (IRS-1) as well as the association between IRS-1 and phosphatidylinositol 3-kinase (PI 3-kinase) in the liver and muscle of rats treated with glucagon. There was a decrease in the insulin-stimulated receptor and IRS-1 phosphorylation levels which was paralleled by a reduced association between IRS-1 and PI 3-kinase in vivo in the liver and muscle of glucagon-treated rats. These observations suggest that glucagon, probably acting through cAMP, may impair insulin signaling in the three early steps in insulin action after binding.

Second-instar larvae of the gypsy moth, Porthetria dispar (L.) were infected with Beauveria bassiana (Balsamo) Vuill. by allowing larvae to crawl over sporulating cultures of the fungus. Virulence of the pathogen was increased by inoculating larvae of the wax moth, Galleria melonella (L.), twice in serial succession. Observations were made on the infectivity and histopathology of the parasite in the host. Penetration of the cuticle occurred 24 h after inoculation and at 64 h post-inoculation the interior was completely filled with hyphae. Penetration of the gut wall was also observed.

Fourth instar larvae of the gypsy moth,Porthetria dispar (L.) were infected with the fungusConidiobolus coronatus(Cost.) Batko using the spore shower technique for varying periods of time. Larvae treated for more than 20 minutes showed 100% mortality. Virulence of the pathogen was increased by inoculating larvae of the wax moth,Galleria mellonella (L.) three times in serial succession. Typical symptoms of the infection were lightening of color, flaccidity, shrinking and finally desiccation of the larvae. Observations on the histopathology of infected larvae showed penetration of the integument by hyphae within 22 hours after inoculation and at 34 hours post inoculation, the hemocoel, head, nervous system and muscles were completely infected. A localized mycelial growth in the digestive system resulted probably due to the ingestion of spores, but penetration of the gut wall was not recorded.

The photographic characteristics of photoactive pigment electrographic imaging systems are investigated by analysis of two model configurations. The results establish which physical parameters control the photographic characteristics. An analysis of electrophoretic display devices is also presented. The models give estimates for the ultimate performance of these systems and make it possible to correlate photographic measurements with related physical phenomena.

The electrical properties of a photoconductor–liquid interface are investigated by a study of transient photostimulated charge transfer from phthalocyanine into an insulating hydrocarbon liquid. The dependence of charge transfer on electric field, light intensity, and concentration of impurities added to the liquid was measured. A theoretical rate constant model is developed for the various processes which contribute to the transient current. Comparing this to the measurements, we find evidence for surface traps at the interface. A model for the desorption rate of ions from the interface is used to obtain an estimate of the adsorption energy of the ion at the interface. Finally, a discussion of probable charge transfer mechanisms is presented.

Larvae of the gypsy mothPorthetria dispar (L.) were infected with sporulating cultures of the fungus,Entomophthora virulentaHall & Dunn using the spore shower technique. The infectivity of the parasite in the host and its histopathology was observed. Penetration of the integument was recorded at 24 hours post-inoculation and conidiophore production occurred at 72 hours after infection. Experiments on mammalian toxicity against laboratory mice showed no significant differences between control and treated mice in body weight, blood cell counts, food and liquid consumption and in the post-mortem examination.

Charge transfer properties of a series of substituted arylazonapthols are shown to correlate with the Hammett's substituent constant σ. For both contact charge exchange of the dyes to metal and field assisted, photostimulated charge transfer from the dyes into nonpolar fluids, the amount of charge transferred is found to increase with increasing σ. However, the efficiency of charge transfer into fluids does not change with σ. In addition the energies of the highest filled and lowest unoccupied molecular levels are shown (by measurement of the oxidation and reduction potentials) to decrease as σ increases. The correlations establish a relationship between charge exchange phenomena and the energy levels of the dyes.

SummaryMycoses of the gypsy moth, Lymantria dispar (L.) by two species of entomogenous fungi, Metarrhizium anisopliae (Metschnikoff) Sorokin and Paecilomyces fumoso-roseus (Wize) Brown and Smith were experimentally established. Infected larvae revealed complete disintegration of viscera within 95 h post-inoculation with M. anisopliae and within 120 h with P. fumoso-roseus. Avian safety studies confirmed the tolerance of large dosages of spore suspensions of both species. Some body weight loss was recorded but all other indicators were not significantly different from the control birds.

Electron-proton elastic scattering cross sections have been measured at the Stanford Linear Accelerator Center at four-momentum transfers squared (q2) of 1.0, 1.5, 2.0, 2.5and 3.75 (GeV/c)2. The angular distributions at q2 = 2.5 and 3.75 (GeV/c)2are sufficient to provide values of the ratio GE/GMindependent of the results from other laboratories. Our results are compatible with scaling, GE(q2) = GM(q2)/μ, within the experimental errors.

A search for a heavy electron of the type considered by Low and Blackmon has been made by studying the inelastic scattering of 5 BeV electrons from hydrogen. The search was made over a range of values of the mass of the heavy electron from 100 to 1300 MeV. No evidence for such a particle was observed. Upper limits on the production cross sections were determined and employed to deduce limits on the values of the electron-photon-heavy electron coupling constant in Low and Blackmon's theory.

Differential cross sections for electrons scattered inelastically from hydrogen have been measured at 18\ifmmode^\circ\else\textdegree\fi{}, 26\ifmmode^\circ\else\textdegree\fi{}, and 34\ifmmode^\circ\else\textdegree\fi{}. The range of incident energy was 4.5 to 18 GeV, and the range of four-momentum transfer squared was 1.5 to 21 ${(\frac{\mathrm{GeV}}{c})}^{2}$. With the use of these data in conjunction with previously measured data at 6\ifmmode^\circ\else\textdegree\fi{} and 10\ifmmode^\circ\else\textdegree\fi{}, the contributions from the longitudinal and transverse components of the exchanged photon have been separately determined. The values of the ratio of the photoabsorption cross sections $\frac{{\ensuremath{\sigma}}_{S}}{{\ensuremath{\sigma}}_{T}}$ are found to lie in the range 0 to 0.5. The question of scaling of $2{M}_{p}{W}_{1}$ and $\ensuremath{\nu}{W}_{2}$ as a function of $\ensuremath{\omega}$ is discussed, and scaling is verified for a large kinematic range. Also, a new scaling variable which reduces to $\ensuremath{\omega}$ in the Bjorken limit is introduced which extends the scaling region. The behavior of ${\ensuremath{\sigma}}_{T}$ and ${\ensuremath{\sigma}}_{S}$ is also discussed as a function of $\ensuremath{\nu}$ and ${q}^{2}$. Various weighted sum rules of $\ensuremath{\nu}{W}_{2}$ are evaluated.

Cross sections for inelastic scattering of electrons from hydrogen were measured for incident energies from 7 to 17 GeV at scattering angles of 6\ifmmode^\circ\else\textdegree\fi{} to 10\ifmmode^\circ\else\textdegree\fi{} covering a range of squared four-momentum transfers up to 7.4 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. For low center-of-mass energies of the final hadronic system the cross section shows prominent resonances at low momentum transfer and diminishes markedly at higher momentum transfer. For high excitations the cross section shows only a weak momentum-transfer dependence.

Charge transfer properties of a series of substituted arylazonapthols are shown to correlate with the Hammett's substituent constant σ. For both contact charge exchange of the dyes to metal and field assisted, photostimulated charge transfer from the dyes into nonpolar fluids, the amount of charge transferred is found to increase with increasing σ. However, the efficiency of charge transfer into fluids does not change with σ. In addition the energies of the highest filled and lowest unoccupied molecular levels are shown (by measurement of the oxidation and reduction potentials) to decrease as σ increases. The correlations establish a relationship between charge exchange phenomena and the energy levels of the dyes.

Fungi to be studied by phase microscopy are Customarily grown on glass slides coated with a thin film of nutrient agar and covered with a sealed glass coverslip (Aist 1969), but growth of obligatory aerobes in such a chamber is limited by the scanty oxygen supply and sporulation does not generally occur.

Electron-proton elastic-scattering cross sections have been measured at the Stanford Linear Accelerator Center for four-momentum transfers squared q^2 from 1.0 to 25.0 (GeV/c)^2. The electric (GEp) and magnetic (GMp) form factors of the proton were not separated, since angular distributions were not measured at each q^2. However, values for GMp were derived assuming various relations between GEp and GMp. Several theoretical models for the behavior of the proton magnetic form factor at high values of q^2 are compared with the data.

The electrostatic field in the development region is mathematically analyzed for a spatially varying image. The effects of space charge due both to charge toner particles and the electrostatic image are included in the field calculation. The results are applied to simple models of xerography and photoactive pigment electrophotography.

Inhibition by 14 isolates of nine species of entomogenous fungi against two strains of the Dutch elm fungus, Ceratocystis ulmi (aggressive and non-aggressive), was evaluated under laboratory conditions. Eleven of the 14 inhibited one or both strains of C. ulmi. Different levels of antagonism were observed at different light levels and temperatures. Beauveria bassiana, Metarhizium anisopliae, and Nomuraea rileyi were antagonistic to both strains of C. ulmi under the four tested combinations of light and temperature. Metarhizium anisopliae produced the highest qualitative level of inhibition. The growth rate of the cultures differed Conventional control measures for the Dutch elm disease (DED) have em- phasized control of the insect vectors, Scolytus scolytus Fabr. and Scolytus mul- tistriatus Marsham, mainly due to the inaccessibility of the pathogen, Ceratocystis ulmi (Buis.) Moreau in the xylem vessels of the elm (Holmes, 1980). Several workers (Doane, 1959; Barson, 1976,1977; Doberski, 1981) have reported patho- genicity in tests for control of the DED insect vectors by the entomogenous fungi, Beauveria bassiana (Bals.) Vuill., Metarhizium anisopliae (Metsch.) Sorokin, Pae- cilomyces farinosus (Dicks ex Fr.) Vuill., and Verticillium lecanii (Zimm.) Viegas. The possible use of these entomogenous fungi in biological control of DED requires investigation of antagonistic interactions between vector and control agent, and also between C. ulmi and each entomogenous fungus. Gibbs and Smith (1978) and Webber (1981) identified several fungal antagonists of C. ulmi. The bacterium, Pseudomonas syringae van Hall, has also demonstrated in vivo an? tagonism in studies by Myers and Strobel (1983), and earlier Holmes (1954) showed Bacillus polymyxa to be an effective inhibitor. The objectives of the present study were to assess the interactions between potential vector control agents (such as entomogenous fungi), and two strains of C. ulmi. Fungal antag? onists of C. ulmi would be efficiently brought into action if they were transported

The optical properties of an electrophotographic film comprised of closely packed submicron selenium spheres embedded in a polymer matrix were investigated. In one case the spheres were arranged in a monolayer; in a second the particles were dispersed throughout the polymer matrix. The optical transmission of these structures was measured as a function of wavelength and particle size and compared with physical models based on Mie theory.