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Notes: Abstract A method is developed for separating νN interactions from interactions involving an intranuclear cascade in νNe scattering at a mean neutrino energy of 145 GeV. The fraction of events featuring a cascade is evaluated by using a sample of νNe charged-current interactions. It is found that the multiplicity of charged particles in the forward direction takes the same value for events with and without a cascade for 4〈W 2〈550 GeV2. In the backward direction, cascade events have the charge multiplicity higher than the multiplicity for cascade-free events by 2.36 units. It is found that particles with momenta less than 2 GeV/c make a dominant contribution to the rescattering process. A depletion of the fastest particles for W 2〈50 GeV2 is observed, in accord with the formation-time concept.

Notes: : Turnip greens, a Brassica, are characterized by a sulfurous aroma, pungent flavor, and a bitter taste due to isothiocyanates, degradation products of glucosinolates. This study examined the sensory characteristics and preference of turnip greens as affected by variety and maturity. A descriptive analysis panel characterized 16 aromas, flavors, and tastes. The intensity of mustard oil/mustard green aroma and flavor and bitterness was significantly affected (P 〈 0.05) by variety. Mustard oil/mustard green aroma and flavor, bitterness, and bitter aftertaste increased significantly (P 〈 0.05) with maturity. Seven Top was preferred significantly (P 〈 0.05) less than the remaining varieties and as the greens matured, preference decreased.

Notes: [Auszug] Cessation of drug use in chronic opiate abusers produces a severe withdrawal syndrome that is highly aversive, and avoidance of withdrawal or associated stimuli is a major factor contributing to opiate abuse. Increased noradrenaline in the brain has long been implicated in opiate ...

Notes: Book reviewed in this article:George W. Liebmann, Solving Problems Without Large Government

Notes: To assess the risk of transmission of infectious haematopoietic necrosis virus (IHNV) associated with the movement of processed rainbow trout, Oncorhynchus mykiss, from an area where the virus is endemic, 240 freshly eviscerated fish (225–500 g) exhibiting spinal curvature or spinal compression types of deformities were tested for IHNV by virus isolation and polymerase chain reaction (PCR) techniques. Commercially produced rainbow trout, approximately 1-year-old, that exhibited spinal deformities were considered to have had a high likelihood of having survived an outbreak of IHN. Serological analysis of fish exhibiting spinal curvature or spinal compression types of deformities for anti-IHNV antibodies resulted in 71 and 50% of the serum samples, respectively, with detectable neutralization activity suggesting previous infection with IHNV. A portion of the skin and muscle in the area of the deformity was collected, as well as brain tissue from each commercially processed fish. Tissue homogenates were tested for IHNV using the epithelioma papulosum cyprini (EPC) cell line pretreated with polyethylene glycol and the chinook salmon embryo (CHSE-214) cell line using standard methods. Nested, reverse transcriptase (RT)-PCR for the detection of IHNV used the central 1231 bp portion of the glycoprotein (G) gene. All brain and skin-muscle homogenates were negative for IHNV by virus isolation and by nested RT-PCR. To assess virus clearance experimentally, groups of 100 specific-pathogen-free (SPF) rainbow trout (mean weight, 100 g) were either intraperitoneally injected with IHNV or sham infected and held separately in 385 L aquaria in SPF water at 15 °C. In the first study, a total of 33% of the infected fish died. Ten days after the last mortality or 34 days after post-infection, six fish from each treatment were killed at weekly intervals for 6 weeks. Kidney and brain homogenates from individual fish were tested by virus isolation and nested RT-PCR using the nucleoprotein (N) gene. All tissue homogenates were negative for IHNV. When this study was repeated, 54% of the infected fish died and beginning 34 days post-infection, six fish from each treatment were killed at biweekly intervals for 8 weeks, and kidney and brain homogenates from individual fish were tested by virus isolation and quantitative real-time PCR utilizing primers and fluorescent labelled probes generated for the specific identification of the N and G genes of IHNV. One brain specimen from an IHN survivor obtained 34 days post-infection was positive by both virus isolation and quantitative PCR; however, all remaining tissue specimens were negative over the 8-week period. Intraperitoneal injection of supernatants from pooled kidney or brain tissue obtained from control or IHN survivor fish into SPF rainbow trout (mean weight, 10 g) also failed to establish virus infection. A strong humoral response was detected in the IHN survivors in both challenge studies and is suggested as a mechanism responsible for virus clearance. These results provide scientific information that can be used to assess the risk associated with the movement of processed rainbow trout from an IHNV endemic area.

Notes: Flavobacterium psychrophilum, the causative agent of bacterial coldwater disease (CWD) and rainbow trout fry syndrome (RTFS), causes high mortality in cultured salmonids. The present study was designed to determine the role antibody plays in conferring protection to rainbow trout fry, Oncorhynchus mykiss (Walbaum), by passive immunization with convalescent serum or serum from adult rainbow trout immunized with F. psychrophilum, and goat anti-F. psychrophilum serum. In each experiment, rainbow trout fry were injected intraperitoneally with antiserum and challenged by subcutaneous injection with a virulent strain (CSF-259-93) of F. psychrophilum 24-h post-immunization. Relative percentage survival (RPS) ranged from 9–42% when rainbow trout fry (mean weight 1.3 g) were injected with a 1:2 dilution of 25 μL of convalescent serum ranging in enzyme-linked immunosorbent assay antibody titres from 1600–102 400. Rainbow trout fry (mean weight 1.0 g) passively immunized with 25 μL of serum from immunized adult fish exhibited RPS values of up to 57%. In each of these experiments, RPS increased with increasing antibody titres against F. psychrophilum. Passive immunization with 25 or 50 μL goat anti-F. psychrophilum serum, however, did not confer protection to fry (mean weight 1.3 g). These results suggest that trout antibody plays a role in conferring protection to F. psychrophilum, but antibody alone is unable to provide complete protection.

Notes: This work describes an experimental study which reviews the various techniques that can be used for determination of anisotropy fields in recording media. At the present time this topic is of considerable importance due to the need to understand the detailed mechanisms of magnetization reversal and the factors that control the switching field distribution in recording media. We have used a metal-particle-based tape material and have employed various magnetic techniques for the determination of the apparent anisotropy field, HK. The techniques included hysteresis loops measured in a direction transverse to the texture direction of the tapes, single-point detection in the successive derivatives of the magnetization with respect to the field, transverse susceptibility measurement, and the variation of the bulk coercivity with temperature. We find the temperature variation of coercivity produces values of HK far smaller than values determined by other methods due to orientation effects. General agreement is seen for the other techniques mentioned and results for samples with differing degrees of texture show that the apparent anisotropy field of the grains as measured by these techniques is influenced greatly by orientation effects. © 2000 American Institute of Physics.

Notes: rf driven multicusp ion sources have been successfully used in various different applications. Lately the Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has been developing a rf ion source for neutron production and a high current density cw-operated ion source for SIMOX (Separation by Implantation of Oxygen)-application. The group has developed a small ion source, which consists of a quartz plasma chamber, an external rf-antenna, an extraction electrode, and a target assembly, all in a tube that is approximately 25 cm in length and 5 cm in diameter. Another neutron generator currently under development is a multiaperture, high power generator. The neutron generator currently operates at 1% duty cycle, 80 kV, and 150 mA of deuterium beam. The neutron yield measured from the generator is 1.6×107 n/s. For oxygen implantation, the group has been developing a source which could provide a high percentage of O+ at high current density using cw operation. A dual-antenna has been developed for the source to ensure reliable long life operation. The development of these sources will be discussed in this article. © 2002 American Institute of Physics.

Notes: We demonstrate that focused Ga+ ion irradiation can comprehensively modify the ferromagnetic properties of Ni80Fe20 thin films. Magneto-optic Kerr effect measurements at room temperature and magnetoresistance measurements at temperatures between 1.5 and 270 K characterized the irradiation effects. Irradiation steadily reduced the films' room temperature coercivity, and a dose of 1.0×1016 ions/cm2 at 30 keV was found sufficient to cause a loss of ferromagnetism at room temperature in films of thickness up to 15.5 nm. In situ end-point detection and postirradiation atomic force microscopy confirmed that the sputtering which accompanied doses up to 1.0×1016 ions/cm2 did not compromise the protective caps on these Ni80Fe20 films. We therefore conclude that the modification of ferromagnetic properties occurred primarily because of direct Ga+ ion implantation. From these results, we speculate that focused Ga+ ion irradiation could be a convenient tool for the nanoscale patterning of magnetic properties in 3d transition metal thin films. © 2001 American Institute of Physics.