5,761 research outputs found
Bar_Code Housing System: la creación de un espacio de investigación interdisciplinar en torno al proyecto de arquitectura
BAR_CODE HOUSING SYSTEM es un proyecto de investigación sobre la vivienda colectiva construida con sistemas industrializados financiado por el Plan Nacional de I+D+i. El objetivo del proyecto es desarrollar un sistema integrado de diseño y construcción asistido por ordenador que facilite la interacción ente los agentes que participan en los procesos de diseño y construcción de viviendas (técnicos, constructores, fabricantes, administración, usuarios). La investigación abarca diversos ámbitos de la arquitectura (proyectos, construcción, estructuras, instalaciones), conjuntamente con la computación. Las tecnologías de la información y comunicación se aplican con la intención de potenciar las relaciones entre estos ámbitos. La interrelación entre las distintas disciplinas y áreas de conocimiento da lugar a un espacio de investigación de carácter transdisciplinar, aunque esencialmente arquitectónico.
Esta estrategia de relaciones propicia la vinculación entre la investigación y la docencia, especialmente cuando se adopta un modelo de educación constructivista
Sustained exocytosis after action potential-like stimulation at low frequencies in mouse chromaffin cells depends on a dynamin-dependent fast endocytotic process
Under basal conditions the action potential firing rate of adrenal chromaffin cells is lower than 0.5 Hz. The maintenance of the secretory response at such frequencies requires a continuous replenishment of releasable vesicles. However, the mechanism that allows such vesicle replenishment remains unclear. Here, using membrane capacitance measurements on mouse chromaffin cells, we studied the mechanism of replenishment of a group of vesicles released by a single action potential-like stimulus (APls). The exocytosis triggered by APls (ETAP) represents a fraction (40%) of the immediately releasable pool, a group of vesicles highly coupled to voltage dependent calcium channels. ETAP was replenished with a time constant of 0.73 � 0.11 s, fast enough to maintain synchronous exocytosis at 0.2-0.5 Hz stimulation. Regarding the mechanism involved in rapid ETAP replenishment, we found that it depends on the ready releasable pool; indeed depletion of this vesicle pool significantly delays ETAP replenishment. On the other hand, ETAP replenishment also correlates with a dynamin-dependent fast endocytosis process (τ = 0.53 � 0.01 s). In this regard, disruption of dynamin function markedly inhibits the fast endocytosis and delays ETAP replenishment, but also significantly decreases the synchronous exocytosis during repetitive APls stimulation at low frequencies (0.2 and 0.5 Hz). Considering these findings, we propose a model in where both the transfer of vesicles from ready releasable pool and fast endocytosis allow rapid ETAP replenishment during low stimulation frequencies.Fil: Moya Diaz, José Abelino. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Alvarez, Yanina Daniela. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Montenegro, Mauricio Norman. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; ArgentinaFil: Bayonés, Lucas. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; ArgentinaFil: Belingheri, Ana Verónica. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: González-Jamett, Arlek M.. Universidad de Valparaiso; ChileFil: Cárdenas, Ana M.. Universidad de Valparaiso; ChileFil: Marengo, Fernando Diego. Universidad de Buenos Aires. Facultad de Ciencias Exactas. Departamento de Ecología, Genética y Evolución. Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentin
Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration
We present the results of prompt optical follow-up of the electromagnetic counterpart of GW170817 by the Transient Optical Robotic Observatory of the South Collaboration (TOROS). We detected highly significant dimming in the light curves of the counterpart over the course of only 80 minutes of observations obtained ∼35 hr after the trigger with the T80-South telescope. A second epoch of observations, obtained ∼59 hr after the event with the EABA 1.5m telescope, confirms the fast fading nature of the transient. The observed colors of the counterpart suggest that this event was a blue kilonova relatively free of lanthanides
Trust in Leadership and Perceptions of Justice in Fostering Employee Commitment
In a period of uncertainty, trust in leadership and perceptions of fairness have emerged as pivotal factors for fostering employee identification and affective commitment. Drawing from authentic leadership theory, this leadership style is identified as a crucial antecedent of affective commitment, examining the mediating role of distributive justice and the moderating role of interactional justice. A quantitative approach was employed, utilizing data from 302 questionnaires completed by Spanish retail workers. For data analysis, SPSS v.25 was used to generate descriptive statistics, while partial least squares structural equation modeling was applied to test the proposed hypotheses. Our findings revealed that authentic leadership is positively associated with the development of affective commitment, with distributive justice acting as a mediating factor between the two. Furthermore, interactional justice negatively moderates the relationship between distributive justice and affective commitment. Contrary to initial expectations, the second moderation, between authentic leadership and affective commitment, was not found to be significant
On the implicit equation of conics and quadrics offsets
A new determinantal representation for the implicit equation of offsets to conics and quadrics is derived. It is simple, free of extraneous components and provides a very compact expanded form, these representations being very useful when dealing with geometric queries about offsets such as point positioning or solving intersection purposes. It is based on several classical results in ?A Treatise on the Analytic Geometry of Three Dimensions? by G. Salmon for offsets to non-degenerate conics and central quadrics.This research was funded by the Spanish Ministerio de Economía y Competitividad and by the European Regional Development Fund (ERDF), under the project MTM2017-88796-P
On the warp drive space-time
In this paper the problem of the quantum stability of the two-dimensional
warp drive spacetime moving with an apparent faster than light velocity is
considered. We regard as a maximum extension beyond the event horizon of that
spacetime its embedding in a three-dimensional Minkowskian space with the
topology of the corresponding Misner space. It is obtained that the interior of
the spaceship bubble becomes then a multiply connected nonchronal region with
closed timelike curves and that the most natural vacuum allows quantum
fluctuations which do not induce any divergent behaviour of the re-normalized
stress-energy tensor, even on the event (Cauchy) chronology horizon. In such a
case, the horizon encloses closed timelike curves only at scales close to the
Planck length, so that the warp drive satisfies the Ford's negative energy-time
inequality. Also found is a connection between the superluminal two-dimensional
warp drive space and two-dimensional gravitational kinks. This connection
allows us to generalize the considered Alcubierre metric to a standard,
nonstatic metric which is only describable on two different coordinate patchesComment: 7 pages, minor comment on chronology protection added, RevTex, to
appear in Phys. Rev.
The Arabidopsis thioredoxin TRXh5regulates the S-nitrosylation pattern of the TIRK receptor being both proteins essential in the modulation of defences to Tetranychus urticae
The interaction between plants and phytophagous arthropods encompasses a complex network of molecules, signals, and pathways to overcome defences generated by each interacting organism. Although most of the elements and modulators involved in this interplay are still unidentified, plant redox homeostasis and signalling are essential for the establishment of defence responses. Here, focusing on the response of Arabidopsis thaliana to the spider mite Tetranychus urticae, we demonstrate the involvement in plant defence of the thioredoxin TRXh5, a small redox protein whose expression is induced by mite infestation. TRXh5 is localized in the cell membrane system and cytoplasm and is associated with alterations in the content of reactive oxygen and nitrogen species. Protein S-nitrosylation signal in TRXh5 over-expression lines is decreased and alteration in TRXh5 level produces changes in the JA/SA hormonal crosstalk of infested plants. Moreover, TRXh5 interacts and likely regulates the redox state of an uncharacterized receptor-like kinase, named THIOREDOXIN INTERACTING RECEPTOR KINASE (TIRK), also induced by mite herbivory. Feeding bioassays performed withTRXh5 over-expression plants result in lower leaf damage and reduced egg accumulation after T. urticae infestation than in wild-type (WT) plants. In contrast, mites cause a more severe injury in trxh5 mutant lines where a greater number of eggs accumulates. Likewise, analysis of TIRK-gain and -loss-of-function lines demonstrate the defence role of this receptor in Arabidopsis against T. urticae. Altogether, our findings demonstrate the interaction between TRXh5 and TIRK and highlight the importance of TRXh5 and TIRK in the establishment of effective Arabidopsis defences against spider mite herbivory.Grants PID2020-115219RB-I00, RED2018-102397-T and RyC17MESFB funded by MCIN/AEI/10.13039/501100011033, as appropriate, by “ERDF A way of making Europe” and by the “European Union” supported this work. Grants, SIMQG-263-1HWZ8Q UPM-Banco Santander Universidades, RyC2017-21814 and PRE2018-083375 from MCIN/AEI supported AA, MES and IRD, respectively. The Spanish Ministry of Science and Innovation (MCIN), the State Research Agency (AEI) and the European Regional Development Fund (ERDF; grant MEC-PID2021-122280NB-I00) financed MCRP and LMS. The Government of Canada through the Ontario Research Fund (RE08-067) and the Natural Sciences and Engineering Research Council of Canada (NSERC, RGPIB-2018-04538) supported VG
Social security health insurance for the informal sector in Nicaragua: a randomized evaluation
This article presents the results from an experimental evaluation of a voluntary health insurance program for informal sector workers in Nicaragua. Costs of the premiums as well as enrollment location were randomly allocated. Overall, take-up of the program was low, with only 20% enrollment. Program costs and streamlined bureaucratic procedures were important determinants of enrollment. Participation of local microfinance institutions had a slight negative effect on enrollment. One year later, those who received insurance substituted toward services at covered facilities and total out-of-pocket expenditures fell. However, total expenditures fell by less than the insurance premiums. We find no evidence of an increase in health-care utilization among the newly insured. We also find very low retention rates after the expiration of the subsidy, with less than 10% of enrollees still enrolled after one year. To shed light on the findings from the experimental results, we present qualitative evidence of institutional and contextual factors that limited the success of this program. Copyright © 2010 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77966/1/1635_ftp.pd
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