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We report on the operation of a coherent population trapping (CPT) microcell atomic clock using a pulsed Ramsey-like interrogation. The Ramsey-CPT sequence, defined by two-step optical pulses separated by a free-evolution dark time, is produced by switching on and off the output power of a low-power vertical-cavity surface-emitting laser, through direct modulation of its driving current. High-contrast and narrow Ramsey-CPT fringes are detected without the use of any external optical modulator stage. We demonstrate closed-loop operation of the clock based on high-speed digital signal processing implemented in a field programmable gate array board. The clock's short-term fractional frequency stability is 1.3 × 10−10 τ − 1 / 2 until 2000 s. A power light-shift coefficient of 8 × 10−11/μW, in relative value, is obtained for a dark time of 150 μs. This value is about ten times lower than in the continuous regime. These results show the feasibility of fully integrated atomic clocks based on Ramsey spectroscopy, which could provide enhanced long-term stability. [ABSTRACT FROM AUTHOR]

The objective of the study was to characterise how pre-service kindergarten teachers used a Hypothetical Learning Trajectory on length and its measurement to notice children's mathematical thinking. A total of 64 pre-service kindergarten teachers enrolled in an Early Years Education mathematics teaching course were asked to notice teaching situations focusing on kindergarten children's learning of length. On the one hand, three profiles of pre-service kindergarten teachers were found according to the use they made of the Hypothetical Learning Trajectory. These profiles were characterised by three ways of learning to use the Hypothetical Learning Trajectory based on the type of mathematical elements they identified: only mathematical elements related to the magnitude; only mathematical elements related to the measurement of length; or both magnitude and measurement elements. On the other hand, when considering the three skills of professional noticing, by identifying the mathematical elements required to solve the proposed task, a group of pre-service kindergarten teachers within each profile were able to notice the thinking of these elements by children and to suggest activities. Our findings provide learning opportunities to pre-service kindergarten teachers who use a Hypothetical Learning Trajectory. It provides them with 'check-points' to answer the proposed questions, in order to learn the specialised knowledge for teaching length and its measurement as well as to develop the skill of noticing student's mathematical thinking. [ABSTRACT FROM AUTHOR]

The use of non-Saccharomyces yeasts means a great source of biodiversity for the production of differentiated beer products. With this objective, five species of different genera have been selected in order to evaluate their influence on beer quality. Two different experiments were carried out with four non-Saccharomyces strains (Schizosaccharomyces pombe, Torulaspora delbrueckii, Saccharomycodes ludwigii and Lachancea thermotolerans) and Saccharomyces cerevisiae, as control. In the first experimental setup, the five strains were used to carry out the pure culture wort fermentation and to undertake bottle conditioning. In a second experimental setup, the wort was fermented with S. cerevisiae and the four non-Saccharomyces strains were used for bottle conditioning. Beers from the first experimental setup had low ethanol content due to the wort's original gravity; T. delbrueckii produced a beer with the largest quantity of isoamyl acetate. In the second setup, the wort had higher original gravity; most of the fermentative volatiles were produced in larger amounts (1-propanol, isobutanol, 2-methyl-1-butanol, 3-methyl-1-butanol) with all tested strains. The differences observed in the volatiles production were more pronounced when the yeast strains were used for the fermentation and the bottle conditioning than whey they were used just for the bottle conditioning. The species S. pombe produced a significantly higher ethanol concentration (%v/v) in both experimental setups; these beers also obtained the highest scores for the sensory attributes foam consistency and foam persistence. Beers produced with T. delbrueckii and S. ludwigii had low ethanol content in both experimental designs, in pure culture fermentation and in bottle conditioning. [ABSTRACT FROM AUTHOR]

Copyright of Avances de Investigación en Educación Matemática is the property of Sociedad Espanola de Investigacion en Educacion Matematica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Purpose: We have reported that exposure to a diabetic intrauterine environment during pregnancy increases blood pressure in adult offspring, but the mechanisms involved are not completely understood. This study was designed to analyse a possible role of perivascular sympathetic and nitrergic innervation in the superior mesenteric artery (SMA) in this effect.Experimental Approach: Diabetes was induced in pregnant Wistar rats by a single injection of streptozotocin. Endothelium-denuded vascular rings from the offspring of control (O-CR) and diabetic rats (O-DR) were used. Vasomotor responses to electrical field stimulation (EFS), NA and the NO donor DEA-NO were studied. The expressions of neuronal NOS (nNOS) and phospho-nNOS (P-nNOS) and release of NA, ATP and NO were determined. Sympathetic and nitrergic nerve densities were analysed by immunofluorescence.Key Results: Blood pressure was higher in O-DR animals. EFS-induced vasoconstriction was greater in O-DR animals. This response was decreased by phentolamine more in O-DR animals than their controls. L-NAME increased EFS-induced vasoconstriction more strongly in O-DR than in O-CR segments. Vasomotor responses to NA or DEA-NO were not modified. NA, ATP and NO release was increased in segments from O-DR. nNOS expression was not modified, whereas P-nNOS expression was increased in O-DR. Sympathetic and nitrergic nerve densities were similar in both experimental groups.Conclusions and Implications: The activity of sympathetic and nitrergic innervation is increased in SMA from O-DR animals. The net effect is an increase in EFS-induced contractions in these animals. These effects may contribute to the increased blood pressure observed in the offspring of diabetic rats. [ABSTRACT FROM AUTHOR]

Background and Purpose We have reported that exposure to a diabetic intrauterine environment during pregnancy increases blood pressure in adult offspring, but the mechanisms involved are not completely understood. This study was designed to analyse a possible role of perivascular sympathetic and nitrergic innervation in the superior mesenteric artery ( SMA) in this effect. Experimental Approach Diabetes was induced in pregnant Wistar rats by a single injection of streptozotocin. Endothelium-denuded vascular rings from the offspring of control ( O- CR) and diabetic rats ( O- DR) were used. Vasomotor responses to electrical field stimulation ( EFS), NA and the NO donor DEA-NO were studied. The expressions of neuronal NOS (n NOS) and phospho-nNOS ( P-n NOS) and release of NA, ATP and NO were determined. Sympathetic and nitrergic nerve densities were analysed by immunofluorescence. Key Results Blood pressure was higher in O- DR animals. EFS-induced vasoconstriction was greater in O- DR animals. This response was decreased by phentolamine more in O- DR animals than their controls. L-NAME increased EFS-induced vasoconstriction more strongly in O- DR than in O- CR segments. Vasomotor responses to NA or DEA-NO were not modified. NA, ATP and NO release was increased in segments from O- DR. n NOS expression was not modified, whereas P-n NOS expression was increased in O- DR. Sympathetic and nitrergic nerve densities were similar in both experimental groups. Conclusions and Implications The activity of sympathetic and nitrergic innervation is increased in SMA from O- DR animals. The net effect is an increase in EFS-induced contractions in these animals. These effects may contribute to the increased blood pressure observed in the offspring of diabetic rats. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Investigación Geográfica is the property of Universidad de la Rioja, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos de Investigación Geográfica is the property of Universidad de la Rioja, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several different types of enzymes and their blends were added to dough with the object of improving the shelf-life of white, lidded-pan bread during storage. Bread firmness and elasticity were determined at 24, 48 and 72 h to determine the influence of the enzymes. Addition of bacterial a-amylase, specially to blends of enzymes also containing lipase and pentosanase, improved white, lidded-pan bread quality by increasing elasticity and lowering firmness of crumb, and enhanced the keeping quality over time by providing a significant 2-day increase in the shelf life. [ABSTRACT FROM AUTHOR]

Continuing an investigation into the different factors affecting the quality of white pan bread and the changes taking place during storage, on the basis of instrumental determinations of firmness using compression and bending tests, this second instalment addresses the influence of adding gluten to the dough. Three types of bread were prepared using three different water contents and three proportions of added gluten each. Firmness was evaluated at 24, 48 and 72 h. Addition of gluten significantly increased flexibility and significantly decreased firmness in the bread at the higher water content levels. It also improved the keeping properties of the bread by slowing the increase in firmness with time; this effect was also higher at the higher water content levels. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the frequency of adverse drug reactions (ADRs) in intensive care units (ICUs) and to evaluate their effect on the length of stay. We performed a prospective study to detect ADRs in 420 patients hospitalised in 10 predetermined beds in the ICU of our hospital between the months of March and December 1996. While the patients were staying in the ICU, data was gathered regarding suspected ADRs and on different variables related to the length of stay. 96 different ADRs were detected in 85 of the 420 patients seen [20.2%, 95% confidence intervals (95% CI) 16.5 to 24.4]. The ADRs were most frequently caused by the following drugs: nitrates (n = 25), opiates (n = 21) and ultrashort-acting benzodiazepines (n = 10). Eight ADRs were severe, the suspected medication had to be discontinued in 51 cases and new drugs were necessary to manage the ADRs in 73 cases. The crude estimation of the effect of the number of ADRs performed with a bivariant regression model indicated that each ADR was related to a 2.38-day increase (95% CI 1.31 to 3.45) in the length of stay. Although this estimation was reduced to 1.76 days (95% CI 0.72 to 2.79), when other confounding variables associated with the length of stay were considered, it was still important.In conclusion, the ADRs were a significant clinical problem in the ICUs and were responsible for a significant increase in the length of stay. [ABSTRACT FROM AUTHOR]

The firmness of white pan bread was measured using compression and bending tests to determine the influence of the water content of the dough on bread quality and on the changes taking place with storage time. Three sample breads were prepared using different flours and three different water contents, and firmness was tested at 24, 48 and 72 h. For gluten-enriched flours, higher water contents tended to bring about a decrease in compression force and bending values, improving shelf-life by reducing the increase in firmness over time. [ABSTRACT FROM AUTHOR]