La utilización de los pedales en la interpretación de Haydn y Mozart

Es una traducción de: Using the Pedals When Playing Haydn and Mozart, en The pianlst's gulde to pedaIing, pp. 136-141, Indiana University Press, 1985.Luis Carlos Gago (traductor)

Production of a Linear Temperature Rise in an Electrical Furnace

Temperature control of an electrical furnace is generally accomplished by means of a servo mechanism. For simple laboratory experiments, however, it may be desirable to control temperature by manual adjustment of power and thus avoid the expense of building a servo. A procedure is offered here for producing a linear temperature rise in an electrical furnace by a time-dependent power function, Q (t). This function is a correspondence of power needed in the heating coil (to produce the desired rate of temperature rise) vs time. A computer analyzes the characteristics of the furnace, calculates the function, and tabulates it. By an iteration of the procedure, the deviation of the temperature-time curve from linearity can be decreased from about 15% to less than 1%

Temperature Variation With Input Power in an Electrical Furnace

Temperature control of an electrical furnace is generally accomplished by means of a servo mechanism. For simple laboratory experiments, however, it may be desirable to produce a selected temperature rise by manual control of a variac or rheostat. A procedure is offered here for producing a linear temperature rise in a furnace at desired points called temperature controlled points. A power function dependent only on time and/or temperature is used. This function is a correspondence of current needed in the coil (to produce the desired temperature rise) versus time and/or temperature

Quantifying the Effects of Acoustic Coupling on Advanced LIGO

The Laser Gravitational Wave Observatory, or LIGO, is built to observe gravitational waves as they propagate through space. Advanced LIGO is extremely sensitive to movements of the test mass as small as 10⁻²¹ m/√Hz , which allows many signals other than gravitational waves to be detected by the system. Pressure created by external sound can alter the measurement by creating Doppler shifts, intensity fluctuations, and scattering in the laser beam. To determine the areas affected by sound external to the vacuum system, we inject acoustic noise in the laser and vacuum equipment area. On a smaller scale, vibrating a horizontal access module or beam splitting chamber with a shaker tests the impact of sound on single chambers. To calculate the scale at which these vibrations impact the signal as well as the effect of other environmental injections, a program that analyzes ambient background noise signals as well as injections with coupling functions to determine the estimated background level of the environmental signal was created. This data analysis program was used to determine the estimated background level of acoustic coupling for each horizontal access module and a ranking of the vacuum chambers most affected by acoustic coupling was developed from this.It was determined that two vacuum chambers had background levels above 10⁻²⁰ m/√Hz. Tests on materials to limit acoustic coupling within a horizontal access module were also conducted and found that using dampening clips within the vacuum chamber was a possible solution to limit acoustic coupling in the 750 Hz range for that chamber

Hydraulic grinding of sorghum grains in the preparation of starches

Call number: LD2668 .T4 1951 B3Master of Scienc

Bactericidal and physico-chemical properties of a lectin derived from spring chinook salmon (Oncorhynchus tshawytscha) Ova

Unfertilized ova from spring chinook salmon (Oncorhynchus tshawytscha) were examined for the presence of classical salmonid inmmunoglobulin. Immunodiffusion techniques in which rabbit anti-salmonid immunoglobulin was reacted against an ova homogenate and rabbit anti-ova homogenate was reacted against immune chinook serum failed to detect classical-type antibodies within these eggs. A lectin with bactericidal properties was isolated from spring chinook salmon ova. This protein agglutinated human type B and rabbit erythrocytes, but not human type A, O or sheep red cells. Hemagglutination was inhibited by D-galactose and L-rhamnose. The protein was purified by affinity chromatography and by gel filtration on Bio-Rad P300. The purified lectin contained a minor (0. 8 %) carbohydrate moiety. A rabbit antiserum was prepared against the protein and used to determine whether ova from coho salmon (O. kisutch), pink salmon (O. gorbuscha), chum salmon (O. keta), kokanee salmon (O. nerka), steelhead trout (Salmo gairdneri), Lahonten cutthroat trout (S. clarki henshawi) or fall chinook salmon (O. tshawytscha) contained a similar protein. All species tested had an immunologically identical protein within their ova. Purified spring chinook salmon ova lectin was bactericidal for two serotypes of Vibrio anguillarum, Pasteurella piscidida, Aeromonas hydrophila and Flexibacter columnaris, but not for Yersinia ruckeri, A. salmonicida, Edwardsiella tarda, Cytophaga psychrophila or the agent of bacterial kidney disease, Corynebacterium sp. In addition to these known bacterial fish pathogens, 19 species of bacteria commonly associated with humans were tested; none of the human-associated agents were inhibited by the lectin. Proteins immunologically identical to the spring chinook salmon ova lectin were purified froim ova of seven other salmonids and found to possess little, if any, activity against the bacterial fish pathogens. Even the protein purified from fall chinook salmon ova had minimal bactericidal activity. Less than 1. 0 μg /ml of the purified spring chinook ova lectin was required for complete inhibition of V. anguillarum growth. A 1 hr incubation of the lectin with the bacteria at 22 C was sufficient for 100% growth inhibition. Microscopic examination of the incubation mixture showed that after 20 min, approximately 50% of the bacteria were no longer motile. No cell lysis was observed. The bacterial inhibition property was stable after heat treatment at 80 C for 6 hr or 100 C for 1 hr. Lyophilization of the protein did not reduce bactericidal activity. The chinook lectin was compared with a plant lectin, ricin, for bactericidal activity and competitive binding of V. anguillarum cells. Although ricin had a carbohydrate specificity similar to the chinook protein, it was not toxic for V. anguillarum; however, it did compete for binding sites on the bacterium. Coho salmon which received 125 μg of purified spring chinook ova lectin intravenously were not protected against subsequent challenge by V. anguillarum

Certain aspects of the immunology and chemotherapy of bacterial kidney disease in juvenile coho salmon (Oncorhynchus kisutch)

The detection and antigenic nature of the causative Corynebacterium of bacterial kidney disease and chemotherapy of this disease in juvenile coho salmon (Oncorhynchus kisutch) were examined. Each of 207 yearling coho salmon collected from a population undergoing a severe epizootic of bacterial kidney disease were examined for the presence of anti-Corynebacterium precipitin or agglutinin antibodies, corynebacteria in Gram-stained kidney smears, and cultivable kidney disease Corynebacterium in kidney material inoculated onto cysteine serum agar. The presence of anti-Corynebacterium precipitin or agglutinin antibodies in the salmon does not serve as a suitable indicator of current infection by the kidney disease bacterium. Coho salmon anti-Corynebacteriurn antibodies appeared to have either cleared the bacteria from the fish or at least reduced the number of kidney disease bacteria to a level not detectable by cultivation of or microscopic examination of kidney tissue. By immunodiffusion and immunoelectrophoresis, two distinct antigens were detected in ammonium sulfate-precipitated material from phosphate-buffered saline extracts of whole Corynebacterium cells. On the basis of chemical analyses, Pronase and heat treatments, both antigens appeared to contain protein and carbohydrate. Three different isolates of the kidney disease Corynebacterium were antigenically similar, Previous work indicating erythromycin as the drug of choice for treating this disease was confirmed, Erythromycin stearate fed at 100 mg per kg of fish per day far two 14-day treatment periods controlled the disease in experimentally infected juvenile coho salmon while Ampicillin and Pen V-K, fed either at 75 or 100 mg per kg of fish per day for two 14-day treatment periods, were ineffective

Life cycle expression analysis of three cell wall degradation-related genes in ethylene-treated grass

Ethylene regulates multiple developmental processes during a plant life cycle, but the effect of ethylene on the upregulation of senescence-, stress-, and post-harvest-related genes in forage grasses is poorly understood. In this work, we used quantitative PCR to determine whether ethylene application affected the expression of selected cell-wall degradation related genes that are typically upregulated post-harvest. The expression levels of beta-D-glucan exohydrolase isoenzyme, alpha glucosidase, and arabinoxylan arabinofuranohydrolase isoenzyme, all putative cell wall degrading enzymes, were quantified at six points in the life cycle of the model grass species Darnel ryegrass (Lolium temulentum L.). We also quantified the expression of ACC oxidase and ACC synthase in response to ethylene application to determine if endogenous upregulation of ethylene biosynthesis occurred. Grass developmental stage had a significant impact on gene expression response to ethylene-treatment, indicating that discrete life cycle stages present different ethylene-responsive windows for treatment. Under our experimental conditions, ACC oxidase and ACC synthase expression were downregulated in response to ethylene-treatment, suggesting that exogenous ethylene served an auto-inhibitory role. Transcripts corresponding to the three cell wall degradation related genes increased significantly in response to ethylene treatment, suggesting that ethylene may have future utility in the pretreatment of lignocellulosic biomass. To our knowledge, this is the first report of a life cycle analysis of ethylene-induced genes in forage grasses.Keywords: Cell wall, Ethylene, Darnel ryegrass, RT-qPCR, Lolium temulentu

Pseudomonas fluorescens SBW25 produces furanomycin, a non-proteinogenic amino acid with selective antimicrobial properties

Background: Pseudomonas fluorescens SBW25 has been extensively studied because of its plant growth promoting properties and potential as a biocontrol agent. The genome of SBW25 has been sequenced, and among sequenced strains of pseudomonads, SBW25 appears to be most closely related to P. fluorescens WH6. In the authors' laboratories, WH6 was previously shown to produce and secrete 4-formylaminooxyvinylglycine (FVG), a non-proteinogenic amino acid with selective herbicidal and antimicrobial activity. Although SBW25 does not have the genetic capacity to produce FVG, we were interested in determining whether this pseudomonad might produce some other type of non-proteinogenic amino acid. Results: P. fluorescens SBW25 was found to produce and secrete a ninhydrin-reactive compound with selective antimicrobial properties. This compound was purified from SBW25 culture filtrate and identified as the non-proteinogenic amino acid L-furanomycin [2S,2'R,5'S)-2-amino-2-(5'methyl-2',5'-dihydrofuran-2'-yl)acetic acid]. Conclusions: The identification of furanomycin as a secondary metabolite of SBW25 is the first report of the production of furanomycin by a pseudomonad. This compound was known previously only as a natural product produced by a strain of Streptomyces. This report adds furanomycin to the small list of non-proteinogenic amino acids that have been identified as secondary products of pseudomonads. This study also extends the list of bacteria that are inhibited by furanomycin to include several plant pathogenic bacteria.Keywords: Non-proteinogenic amino acids, 4-formylaminooxyvinylglycine, Pseudomonas fluorescens SBW25, Pseudomonas fluorescens WH6, Furanomycin, Secondary metabolites, Antimicrobial activit