Method and apparatus for using magneto-acoustic remanence to determine embrittlement

A method and apparatus for testing steel components for temperature embrittlement uses magneto-acoustic emission to nondestructively evaluate the component are presented. Acoustic emission signals occur more frequently at higher levels in embrittled components. A pair of electromagnets are used to create magnetic induction in the test component. Magneto-acoustic emission signals may be generated by applying an AC current to the electromagnets. The acoustic emission signals are analyzed to provide a comparison between a component known to be unembrittled and a test component. Magnetic remanence is determined by applying a DC current to the electromagnets and then by turning the magnets off and observing the residual magnetic induction

The molecular structure of isocyanic acid from microwave and infra-red absorption spectra

Experimental investigations of the infra-red and microwave spectra of the slightly asymmetric rotor, HNCO, have been made, and the structure of the molecule has been determined

Rate of the Rapid Gas Phase Reaction between NO, NO_2, and H_2O

Following the successful application by Johnston and Yost of the cathode-ay oscillograph to the study of the very rapid reaction between nitrogen dioxide and ozone, we have applied this technique to the following reaction, which NO(g) + NO_2(g) + H_2O(g) = 2HNO_2(g) is also probably involved in the atmosphere immediately after a lightning stroke, and which has been reported to be practically instantaneous. In a trapped non-equilibrium mixture of the reacting gases the concentration of nitrogen dioxide was followed by photographing the screen of an oscilloscope which registered the output voltage of a multiplier photo-tube exposed to a chopped beam of blue light emergent from the reaction cell

Dvr1 transfers left–right asymmetric signals from Kupffer's vesicle to lateral plate mesoderm in zebrafish

AbstractAn early step in establishing left–right (LR) symmetry in zebrafish is the generation of asymmetric fluid flow by Kupffer's vesicle (KV). As a result of fluid flow, a signal is generated and propagated from the KV to the left lateral plate mesoderm, activating a transcriptional response of Nodal expression in the left lateral plate mesoderm (LPM). The mechanisms and molecules that aid in this transfer of information from the KV to the left LPM are still not clear. Here we provide several lines of evidence demonstrating a role for a member of the TGFβ family member, Dvr1, a zebrafish Vg1 ortholog. Dvr1 is expressed bilaterally between the KV and the LPM. Knockdown of Dvr1 by morpholino causes dramatically reduced or absent expression of southpaw (spaw, a Nodal homolog), in LPM, and corresponding loss of downstream Lefty (lft1 and lft) expression, and aberrant brain and heart LR patterning. Dvr1 morphant embryos have normal KV morphology and function, normal expression of southpaw (spaw) and charon (cha) in the peri-KV region and normal expression of a variety of LPM markers in LPM. Additionally, Dvr1 knockdown does not alter the capability of LPM to respond to signals that initiate and propagate spaw expression. Co-injection experiments in Xenopus and zebrafish indicate that Dvr1 and Spaw can enhance each other's ability to activate the Nodal response pathway and co-immunoprecipitation experiments reveal differential relationships among activators and inhibitors in this pathway. These results indicate that Dvr1 is responsible for enabling the transfer of a left–right signal from KV to the LPM

Research Notes : United States : Genetic studies with two mutagen-induced nonfluorescent root mutants

In the preceding article, we described several nonfluorescent root lines that had been obtained from induced mutagenesis. Seeds of the cultivar \u27Williams\u27 had been treated with 20k.R gannna rays. The seeds given to us were a bulk harvest of many M2 plants. Only two nonfluorescent seedlings, desig-nated IL 3-1 and IL 3-2, were found among the 5,262 seeds germinated