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Effects were investigated of certain physical and chemical characteristics on muskmelon texture as described by sensory evaluation. Turgor pressure, moisture content and concentrations of total sugars, alcohol insoluble solids, three pectin fractions, starch and cellulose were determined in 50 melons purchased randomly from a retail market. Sensory assessments included crispness, fibrous-ness, and resistance to cutting, biting and crushing. Results indicated that the texture of muskmelon is determined largely by the type and amount of cell wall constituents. Maturity, inferred from starch and protopectin content, also affected sensory panel scores. Moisture, alcohol insoluble solids, total sugars and pectic substances, except protopectin, were not reliable texture indicators. Although turgor pressure was not related significantly to any textural characteristics, a trend was observed suggesting that this variable warrants further investigations.

espanolObjetivo. Mujeres jovenes con cancer pueden beneficiarse de opciones para la preservacion de su fertilidad. Se necesitan estudios que determinen las implicaciones psicologicas de someterse a estas tecnicas y de la propia decision de recibirlas. Este estudio analiza el distres emocional, las preocupaciones sobre la fertilidad, las actitudes ante la maternidad, la satisfaccion con la informacion recibida y el apoyo social en mujeres con cancer que reciben un tratamiento de preservacion de la fertilidad. Metodo. Una muestra de 115 mujeres (edad media 31 anos) recien diagnosticas de cancer fueron evaluadas (Entrevista semiestructurada, Escala de apoyo social percibido, BSI-18) el mismo dia o dia despues de someterse a una criopreservacion de tejido ovarico. Resultados. El grado de preocupacion manifestado por las mujeres cuando supieron que el tratamiento del cancer podria afectar su capacidad reproductiva fue alto. Casi la mitad declaro que cambiarian la informacion recibida sobre el tratamiento de preservacion de la fertilidad. Un mayor distres se asocio significativamente con mayor deseo de tener hijos, la creencia de que tener hijos es necesario para la relacion de pareja, el deseo de cambiar la informacion recibida, mayor grado de preocupacion por la posible perdida de fertilidad y menor apoyo social. Conclusiones. Tanto las actitudes hacia la maternidad como el apoyo social son factores que determinan el distres emocional que experimentan las mujeres jovenes con cancer cuando se enfrentan a la posible perdida de infertilidad. Es necesario ofrecer asesoramiento sobre la preservacion de la fertilidad a estas mujeres. EnglishObjective. Young women with cancer can benefit from various treatment options for fertility preservation. More work is needed to discern which factors affect psychological outcomes and the decision to undergo fertility preservation for female cancer survivors. The purpose of this study was to examine the relationship between attitudes toward motherhood, concerns about fertility, satisfaction with information received, social support and emotional distress among young women with cancer undergoing fertility preservation treatment. Method. Cross-sectional administration of instruments (semi-structured interview, Scale of Perceived Social Support, BSI-18) to 115 young women (average age 31 years) newly diagnosed with cancer. Assessment was done on the same day or day after undergoing Ovarian Tissue Cryopreservation (OTC). Results. The degree of concern reported by the women when they knew that cancer treatment might affect their reproductive capacity was high. Almost half stated that they would change the treatment-related information they received. Factors influencing their decision to receive OTC include the importance of having a child and maintaining hormonal function. Higher emotional distress was significantly associated with increase desire to have children, belief that having children is necessary for couple´s fulfillment, desire to change the information received, higher degree of concern about the possible loss of fertility, and less perceived social support. Conclusions. Both attitudes to motherhood and social support are factors that determine the emotional distress experienced by young women with cancer when faced with the possible loss of infertility. There is a need to offer fertility preservation counseling to these women.

The reciprocal recurrent selection technique for improving combining ability was tested with two strains of chickens. Body weight of broilers was the criterion. Selection was based on the 10-week body weights of crossbred progeny but only selected individuals from the purebred strains were used as parents of succeeding generations. Random-bred control strains, in which no selection was practised, were also maintained and reproduced to assist in evaluating genetic change in the selected strains.Reciprocal recurrent selection brought about a progressive increase in the body weight of both purebred and crossbred broilers from the strains under selection. Broilers from the selected strains were 11.3 per cent heavier at 10 weeks of age than those from their unselected counterparts at the end of the experiment. Broilers from the control strains maintained a nearly constant weight. Purebred broilers from the selected strains increased in weight as the experiment progressed, at approximately the same rate as crossbreds from the same strains. Selection apparently resulted in an accumulation of genes having an additive favorable effect on body weight, but it failed to improve combining ability. Over-dominance and/or epistasis did not appear to be important factors in heterosis for body weight in these populations.

The interpretation of the 1H n.m.r. spectrum of a meta-substituted biphenyl (3,3′,5,5′-tetrachlorobiphenyl) dissolved in the nematic phase of a liquid crystalline solvent showed unambiguously that in solution it has neither a planar structure nor free rotation but exists in a twisted conformation. A fairly accurate measurement of the twisting angle could also be obtained (34° 20′), the experimental error being similar to that reported in the electron diffraction studies of the vapour phase. The effects of the substituents and of the nematic solvent upon the conformation are discussed and the conclusion is reached that they are rather small and acting in opposite directions. Biphenyl is thus expected to have a similar dihedral angle in solution.

Monomer reactivity ratios and copolymerization parameters were determined for n-octadecyl acrylate and N-n-octadecylacrylamide with several monomers not previously reported. Values of Q and e for the long-chain acrylate now agreed more closely than before with the average of values for the lower acrylate homologs. The average polarity parameter for N-n-octadecylacrylamide still showed more electron withdrawal from the double bond (e = 0.42) than was expressed by the average literature value (e = −0.10) for N-n-octylacrylamide. Because penultimate effects were absent in this work, the reason for the discrepancy seems to reside in the copolymer analysis. Reactivity ratios for oleyl and octadecyl acrylate with methyl methacrylate were similar. Coefficients for the relation between overall rates of copolymerization and composition were obtained on some systems by curve fitting with a computer. They generally showed a slight minimum.

Frozen, dehydrated and refrigerated potato products taken directly from the package, and fresh potatoes washed and peeled contained microorganisms, ranging from very low counts for finish-cooked French Fried potatoes, Tots and Treats, to high counts for some brands of frozen, partially-cooked products. The organisms were mostly gram positive bacilli, although most products also contained flat sour spores and acidtolerant bacteria. There were no thermophilic anaerobes. If temperatures approached 90 C during cooking, all viable microorganisms were destroyed. No microorganisms could be demonstrated when these cooked products were held at 10 C for forty-eight hours, at 25 C or at 50 C for four hours. Cooking temperatures ranging from 50 to 70 C resulted in reduced numbers of microorganisms. Counts remained low during holding at 10 C for forty-eight hours and at 25 C or 50 C for four hours.

SUMMARY: The volatile flavor components of a lightly milled, whole-grain soft wheat, Moro variety, were isolated and studied by gas-liquid chromatography, mass spectrometry, Paper chromatography and/or chemical tests. The following 11 compounds were identified in the wheat flavor essence or in headspace vapors: acetaldehyde, isobutyraldehyde, butyraldehyde, hexanal, heptanal, octanal, crotonaldehyde, 3-methyl-2-butanone, 2,2-dimethyl-3-pentanone, diacetyl and ethyl acetate. Tentative identifications were made of seven additional compounds: butanone, valeraldehyde, isovaleraldehyde, cyclopentanone, phenylacetaldehyde, amyl alcohol and isoamyl alcohol.

SUMMARY— A method is reported for preparing cake batter for microscopic study through the technique of freeze-drying, followed by fixation and staining of the fat with osmium tetroxide, infiltration with paraffin, and sectioning of the freeze-dried batter. Microscopic examination reveals that a cake batter is an emulsion of fat in an aerated aqueous phase. The fat particles are irregularly “globular” shaped droplets dispersed throughout the aqueous starch-protein system. In like manner, the air bubbles are dispersed in the batter. They are not incorporated in the fat particles, but are instead distributed throughout the aqueous phase.

La fabricación de nanoestructuras usando ADN como material para construir sistemas capaces de realizar funciones complejas es una frontera en continua exploración. En este artículo se reporta la caracterización detallada a nivel atómico de unidades de G-cuádruple para obtener una mejor comprensión de cómo estas unidades se pueden auto ensamblar en oligómeros tipo G-cuádruple entrelazado (interlocked G-quadruplexes). Para esto se utilizaron métodos de modelación con mecánica molecular. Previamente reportamos la construcción de G-cuádruple entrelazados por un procedimiento térmico cíclico (similar en implementación al usado para el ciclado de un protocolo de PCR) partiendo de la secuencia 5’-TGGG-3’. Basados en nuestros datos experimentales reportados anteriormente se construyeron modelos para las estructuras y se minimizaron y analizaron vía mecánica molecular para entender los factores que determinan la estructura más estable. Se encontró que la identidad de los extremos 5’y 3’de los oligonucleótidos es de importancia fundamental en la estabilidad de los ensambles de ADN en el estudio. Además, los cationes en las regiones donde el grado de impedimento estérico permite más espacio para los mismos, pueden jugar un rol significativo en la dinámica de la conformación de la supramolecula en esos sitios, posiblemente limitando el auto ensamblaje de la estructura. En resumen, los resultados permiten mejorar la comprensión de este sistema a escala molecular permitiendo desarrollar procedimientos más eficientes para el control de la fabricación de nanoestructuras basadas en DNA G-cuádruple.

La fabricación de nanoestructuras a partir de biomoléculas como fibras de ADN es una frontera en continua exploración gracias a una multitud de aplicaciones potenciales en sistemas biológicos complejos. Las secuencias analizadas se encuentran en sistemas biológicos como en orígenes de replicación de virus y bacterias. En este artículo se reporta la caracterización detallada a nivel atómico de ADN rico en Guaninas que forman estructuras en cremallera. Para esto se utilizaron métodos de modelación con mecánica molecular. Se construyeron modelos para las estructuras y se minimizaron, lo cual permitió su análisis vía mecánica molecular para entender los factores que determinan la estructura más estable. Se encontró que la presencia de iones con carga positiva cercanos a la región rica en Gs de las secuencias estudiadas es de importancia fundamental en la estabilidad de estos ensambles de ADN. En resumen, los resultados permiten mejorar la comprensión de este sistema a escala molecular permitiendo desarrollar procedimientos más eficientes para el control de la fabricación de nanoestructuras en ADN en cremallera y encontrar sus aplicaciones en sistemas biológicos.

Diakonia, Bd. 18 Nr. 6 (1987): Diakonia, Band 18, Heft 6

Partial rate factors have been determined for molecular chlorination in nitromethane and protodesilylation in H2SO4–AcOH mixtures of methyl phenyl and diphenyl sulphoxide. The electron-activating effect observed in molecular halogenation is interpreted in terms of polarization of the sulphoxide group in the transition state, induced by the electrophilic reagent. In H2SO4–AcOH mixtures Krel for protodesilylation at the para-position of methyl phenyl sulphoxide is very low, possibly because of hydrogen bonding between the sulphinyl group and the acidic medium. For methyl phenyl sulphide, sulphoxide, and some other compounds the ground state electron densities at the para-position have been evaluated from their 13C n.m.r. spectra.

The 13C n.m.r. spectra of the four symmetrical naphthyridines have been obtained and assignment of the signals performed by means of heteronuclear decoupling experiments and empirical additivity methods. The shifts were found to depend linearly upon the total charge density on the carbon atoms as calculated by self-consistent molecular orbital INDO and CNDO approximations.