3-D Kinematics of the HH 110 jet

We present new results on the kinematics of the jet HH 110. New proper motion measurements have been calculated from [SII] CCD images obtained with a time baseline of nearly fifteen years. HH 110 proper motions show a strong asymmetry with respect to the outflow axis, with a general trend of pointing towards the west of the axis direction. Spatial velocities have been obtained by combining the proper motions and radial velocities from Fabry-Perot data. Velocities decrease by a factor ~3 over a distance of ~10$^{18}$ cm, much shorter than the distances expected for the braking caused by the jet/environment interaction. Our results show evidence of an anomalously strong interaction between the outflow and the surrounding environment, and are compatible with the scenario in which HH 110 emerges from a deflection in a jet/cloud collision.Comment: (1)Universitat de Barcelona; (2)UNAM; (3)UPC; (4)University of Hawaii; (5)Southern Astrophysical Research Telescope. 9 pages; 7 Figures Accepted by A&

Dynamic modeling and controllability analysis of an ethanol reformer for fuel cell application

This work presents a controllability analysis of a low temperature ethanol reformer based on a cobalt catalyst for fuel cell application. The study is based on a nonlinear dynamic model of a reformer which operates in three separate stages: ethanol dehydrogenation to acetaldehyde and hydrogen, acetaldehyde steam reforming, and water gas shift reaction. The controllability anal ysis is focused on the rapid dynamics due to mass balances and is based on a linear ization of the complex non-linear model of the reformer. RGA, CN and MRI analysis tools are applied to the linear model suggesting that a good performance can be obtained with decentralized control for frequencies up to 0.1 rad/s.Peer ReviewedPostprint (author's final draft

Building C(sp(3)) Molecular Complexity on 2,2 '-Bipyridine and 1,10-Phenanthroline in Rhenium Tricarbonyl Complexes

The reactions of [Re(N-N)(CO)(3)(PMe3)]OTf (N-N=2,2 '-bipyridine, bipy; 1,10-phenanthroline, phen) compounds with tBuLi and with LiHBEt3 have been explored. Addition to the N-N chelate took place with different site-selectivity depending on both chelate and nucleophile. Thus, with tBuLi, an unprecedented addition to C5 of bipy, a regiochemistry not accessible for free bipy, was obtained, whereas coordinated phen underwent tBuLi addition to C2 and C4. Remarkably, when LiHBEt3 reacted with [Re(bipy)(CO)(3)(PMe3)]OTf, hydride addition to the 4 and 6 positions of bipy triggered an intermolecular cyclodimerization of two dearomatized pyridyl rings. In contrast, hydride addition to the phen analog resulted in partial reduction of one pyridine ring. The resulting neutral Re-I products showed a varied reactivity with HOTf and with MeOTf to yield cationic complexes. These strategies rendered access to Re-I complexes containing bipy- and phen-derived chelates with several C(sp(3)) centers

Flipping the classrrom in courses of statistics: analyzing the feedback from students

[EN] We present the application of the flipped classroom strategy in two subjects of the degree in Statistics (University of Barcelona-Polytechnic University of Catalonia) and analyse the opinion of students about the experience. The objective is to improve the learning process of statistics by promoting a more active attitude of students in the classroom. The new strategy has been welcomed by students, as most of them are satisfied with the experience. Many of them would like that the stratgy would be applied to a significant number of lessons in the subject, or even in other subjects of the degree. Moreover, students think that it helped them to develop their capacity to organize their study time and their self-learning competence. They also think that with the flipped classroom strategy they learn more than with the traditional classes, but they remark the importance of imcluding a session where the teacher answers the questions and solves the doubts of students to ensure a sucessful implementation.http://ocs.editorial.upv.es/index.php/HEAD/HEAD18Alcañiz, M.; Lopez-Tamayo, J.; Perez-Marin, A.; Riera, C.; Santolino, M.; Chulia, H. (2018). Flipping the classrrom in courses of statistics: analyzing the feedback from students. Editorial Universitat Politècnica de València. 1011-1018. https://doi.org/10.4995/HEAD18.2018.8136OCS1011101

Multi-Generational Star Formation in L1551

The L1551 molecular cloud contains two small clusters of Class 0 and I protostars, as well as a halo of more evolved Class II and III YSOs, indicating a current and at least one past burst of star formation. We present here new, sensitive maps of 850 and 450 um dust emission covering most of the L1551 cloud, new CO J=2-1 data of the molecular cloud, and a new, deep, optical image of [SII] emission. No new Class 0/I YSOs were detected. Compact sub-millimetre emitters are concentrated in two sub-clusters: IRS5 and L1551NE, and the HL~Tauri group. Both stellar groups show significant extended emission and outflow/jet activity. A jet, terminating at HH 265 and with a very weak associated molecular outflow, may originate from LkHa 358, or from a binary companion to another member of the HL Tauri group. Several Herbig Haro objects associated with IRS5/NE were clearly detected in the sub-mm, as were faint ridges of emission tracing outflow cavity walls. We confirm a large-scale molecular outflow originating from NE parallel to that from IRS5, and suggest that the "hollow shell" morphology is more likely due to two interacting outflows. We confirm the presence of a prestellar core (L1551-MC) of mass 2-3 Mo north-west of IRS5. The next generation cluster may be forming in this core. The L1551 cloud appears cometary in morphology, and appears to be illuminated and eroded from the direction of Orion, perhaps explaining the multiple episodes of star formation in this cloud. The full paper (including figures) can be downloaded at http://www.jach.hawaii.edu/~gms/l1551/l1551-apj641.pdf, or viewed at http://www.jach.hawaii.edu/~gms/l1551/.Comment: Accepted for publication in The Astrophysical Journal, April 2006 (vol. 641). 27 pages, 17 figure

Proper Motions of the Jets in the Region of HH 30 and HL/XZ Tau. Evidence for a Binary Exciting Source of the HH 30 Jet

We present [SII] images of the HH 30 and HL/XZ Tau region obtained at two epochs, as well as long-slit optical spectroscopy of the HH 30 jet. We measured proper motions of about 100-300 km/s for the HH 30 jet and counterjet, and of about 120 km/s for the HL Tau jet. Inclination angles with respect to the plane of the sky are 0-40 deg for the HH 30 jet and 60 deg for the HL Tau jet. Comparison with previous observations suggests that most of the jet knots consist of persisting structures. Also, we corroborate that the HH 30-N knots correspond to the head of the HH 30 jet. The overall HH 30 jet structure can be well described by a wiggling ballistic jet, arising either by the orbital motion of the jet source around a primary or by precession of the jet axis because of the tidal effects of a companion. In the first scenario, the orbital period would be 53 yr and the total mass 0.25-2 solar masses. In the precession scenario, the mass of the jet source would be 0.1-1 solar masses, the orbital period <1 yr, and the mass of the companion less than a few times 0.01 solar masses, thus being a substellar object or a giant exoplanet. In both scenarios a binary system with a separation <18 AU (<0.13 arcsec) is required. Since the radius of the flared disk observed with the HST is about 250 AU, we conclude that this disk appears to be circumbinary rather than circumstellar, suggesting that the search for the collimating agent of the HH 30 jet should be carried out at much smaller scales.Comment: 42 pages, 7 figures, 5 tables. To Appear in The Astronomical Journal, Vol. 133 No. 6 (June 2007

Vocal caricatures reveal signatures of speaker identity

What are the features that impersonators select to elicit a speaker’s identity? We built a voice database of public figures (targets) and imitations produced by professional impersonators. They produced one imitation based on their memory of the target (caricature) and another one after listening to the target audio (replica). A set of naive participants then judged identity and similarity of pairs of voices. Identity was better evoked by the caricatures and replicas were perceived to be closer to the targets in terms of voice similarity. We used this data to map relevant acoustic dimensions for each task. Our results indicate that speaker identity is mainly associated with vocal tract features, while perception of voice similarity is related to vocal folds parameters. We therefore show the way in which acoustic caricatures emphasize identity features at the cost of loosing similarity, which allows drawing an analogy with caricatures in the visual space.Fil: Lopez, Sabrina Laura. 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; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Sistemas Dinámicos; ArgentinaFil: Riera, Pablo Ernesto. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Acustica y Percepción Sonora; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Assaneo, María Florencia. 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; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Sistemas Dinámicos; ArgentinaFil: Eguia, Manuel Camilo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Acustica y Percepción Sonora; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sigman, Mariano. 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; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Neurociencia Integrativa; Argentina. Universidad Torcuato Di Tella; ArgentinaFil: Trevisan, Marcos Alberto. 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; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Sistemas Dinámicos; Argentin

Increased rate of FEV1 decline in HIV patients despite effective treatment with HAART

Introduction: Previous studies have reported that the rate of FEV1 decline over time is increased in HIV patients but the mechanisms underlying this observation are unclear. Since current HIV treatment with Highly Active Antiretroviral Therapy (HAART) results in very good immune-viral control, we hypothesized that HAART should normalize the elevated rate of FEV1 decline previously reported in HIV patients if it was somehow related to the immune alterations caused by HIV, particularly in never smokers or quitters, since smoking is a well established risk factor for accelerated FEV1 decline in the general population. Methods: We explored this hypothesis in a prospectively recruited cohort of 188 HIV (smoker and non-smoker) patients treated with HAART in Palma de Mallorca (Spain) and followed-up for 6 years. The cross-sectional characteristics of this cohort have been published elsewhere. Results: We found that: (1) HAART resulted in good immune-viral control; (2) the rate of FEV1 decline remained abnormally elevated, even in non-smokers and quitters; and, (3) alcohol abuse during follow-up was related to FEV1 decline in these patients. Discussion: Despite adequate immune-viral control by HAART, lung function decline remains increased in most HIV patients, even in non-smokers and quitters. Alcohol abuse is a preventable risk factor to decrease the accelerated FEV1 decline in this population