End-point estimates for iterated commutators of multilinear singular integrals

Iterated commutators of multilinear Calderon-Zygmund operators and pointwise multiplication with functions in $BMO$ are studied in products of Lebesgue spaces. Both strong type and weak end-point estimates are obtained, including weighted results involving the vectors weights of the multilinear Calderon-Zygmund theory recently introduced in the literature. Some better than expected estimates for certain multilinear operators are presented too.Comment: A typo in the original manuscript lead to overlook a gap in one of our arguments which has been fixed. The new arguments are provided in the proof of Theorem 3.1 in Section 3. With the exception of some new notation introduced and some minor changes in wording in a few places, those new details are the only modifications to the original manuscrip

Uma visão crítica do debate atual sobre a estagnação secular

La escena actual de exiguo y frágil crecimiento de las economías centralesprovocó la reaparición de la hipótesis de estancamiento secular. Unsegmento de las explicaciones actuales atribuye esta paralización del nivelde acumulación a la gestación de un exceso de ahorro agregado, pero rehúsadetenerse en la función cumplida por las ganancias retenidas en el senode las empresas. En este trabajo se ofrece una estimación a nivel rama deactividad de ese exceso de ahorro empresario, para 15 países de la OCDE, yse documenta su tendencia ascendente desde 1980. Asimismo, se discutenindicios que permiten postular que ciertas transformaciones de largo plazoexperimentadas por la acumulación de capital a nivel mundial (caída decostos laborales, intensificación del comercio y la inversión internacionales,agudización de la competencia, sobrecapacidad, etc) contribuyeron al estancamiento.The current stage of meager and fragile growth in the central economies provoked the reappearance of the hypothesis of secular stagnation. A group of theoretical explanations attributes the stagnation to the development of aggregate excess savings, but refuse to dwell on the role played by retained earnings within companies. This paper offers an estimate of the excess savings at the industry level for 15 OECD countries, and documents its upward trend since 1980. In addition, it discusses further evidence that allows to put forward that certain long-term transformations experienced by the accumulation of capital worldwide (falling labor costs, increased international trade and investment, intensification of competition, overcapacity, etc) contributed to stagnation.O cenário atual de crescimento magro e frágil nas economias centrais causou o reaparecimento da hipótese de estagnação secular. Um segmento de explicações correntes atribuiu essa paralisia do nível de acumulação para a gestação de excesso de poupança agregada, mas recusa-se a estudar o papel desempenhado pelos lucros acumulados das empresas. Fizemos uma estimativa do excesso do poupança empresário, para diferentes indústrias em 15 países da OCDE, e observa-se tendência de aumento desde 1980.Fil: Perez Artica, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Económicas y Sociales del Sur. Universidad Nacional del Sur. Departamento de Economía. Instituto de Investigaciones Económicas y Sociales del Sur; Argentin

Fitting and selecting scattering data

The main purpose of scattering experiments is to unveil the underlying structure of the colliding particles and their interaction. Typically one measures scattering observables (cross sections and polarizations) at discrete angles and energies and mutually consistent data may validate or falsify proposed theories or models. However, the accumulation of data from different laboratories while potentially improves the statistical significance it may sometimes generate mutually inconsistent data as a side-effect. Thus, some decision has to be made on what are the maximal amount of data which are mutually compatible. We show elastic $\pi N$ and $NN$ scattering as prominent examples where this selection is called for. We discuss how it can be done in a self-consistent manner invoking a principle of maximal consensus of the database and with the help of a sufficiently flexible model involving a minimal number of theoretical assumptions. In the NN case this has become possible with a combination of long distance field theoretical constraints at the hadronic level such as pion exchanges and electromagnetic effects and a coarse graining of the unknown interaction over the shortest de Broglie wavelength being probed in the scattering process.Comment: 7 pages, 5 figures, talk presented by ERA at XVII International Conference on Hadron Spectroscopy and Structure - Hadron2017, Salamanca, 25-29 September 201

El ahorro y los obstáculos a la inversión en la cadena de valor automotriz: Una propuesta teórica y empírica

Este trabajo inicia un estudio del comportamiento empresario en el sector automotriz, en particular referido al desempeño del ahorro y la inversión a nivel firma. Primero, se discuten teóricamente los límites a la inversión de las firmas que pueden surgir del particular funcionamiento de la cadena de valor, y otros factores financieros y operativos capaces de conducir a situaciones de exceso de ahorro. Segundo, se estudia empíricamente el comportamiento de estas variables en firmas de América Latina, comparándolo con otras regiones del mundo. Los resultados sugieren la existencia de obstáculos más marcados a la inversión y crecimiento de firmas automotrices en América Latina que en las restantes regiones analizadas.This work begins a study of fi rm performance in the automotive industry, particularly based on the performance of savings and investment at the fi rm level. Firstly, it theoretically discusses fi rms` investment restrictions stemming from the specifi c nature of the value chain, and other fi nancial and operational factors prone to generate excess savings at the fi rm level. Second, it empirically studies the behaviour of these variables in fi rms from Latin America, compared to those from other relevant regions of the world. The results suggest the existence of more marked obstacles to investment and growth in automakers from Latin America.Fil: Perez Artica, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Económicas y Sociales del Sur. Universidad Nacional del Sur. Departamento de Economía. Instituto de Investigaciones Económicas y Sociales del Sur; Argentin

Measuring the effect of immediacy on consumer engagement behaviours in social media settings

This thesis presents evidence of how immediacy affects consumer engagement behaviour in a social media setting. It answers the research question: Does immediacy influence consumer engagement behaviours with brands on Facebook? This research context is important and timely because of the rapidly increasing usage of social media by consumers and the resultant unexplored marketing challenges faced by brand managers. This thesis is informed by Social Impact Theory (SIT) (Latané, 1981), which proposes that immediacy is a determinant of influence in off-line environments. This study focuses upon three forms of immediacy, physical, social and temporal, that are identified within prior literature. This thesis measures the effect and develops SIT to account for immediacy as a social influence determinant of social media behaviour. The thesis follows a mixed method approach using focus groups and experimental design to measure the impact of each form of immediacy on four types of engagement behaviour: page liking, content liking, content sharing and content commenting. A series of three focus groups and three experimental studies were conducted with a total of 312 student participants who were presented with Facebook pages (created specifically for this study). Each Facebook page treatment was modified so that it contained either a high, low or neutral levels of each of the three types of immediacy identified in the literature and the subsequent change in participant engagement behaviour was measured. The results show that social immediacy significantly affects brand engagement intentions in terms of page liking, content liking and content sharing, whereas physical immediacy significantly affected page liking and content liking intentions. Temporal immediacy did not show any effects on the engagement intentions being measured in this thesis. This thesis presents three original contributions to knowledge. First, it makes a theoretical contribution by measuring the effects of three types of immediacy as social impact factors on engagement behaviours in social media. Second, it makes a contextual contribution by exploring how immediacy is perceived in the context of Fan pages, and by identifying other factors that can moderate the social impact of immediacy on consumer behaviour. Finally, this thesis measures the effects of product involvement, Facebook intensity usage and gender as moderators of social impact in social media settings

Modelling the exposure to Cronobacter sakazakii by consumption of a cocoa-milk-based beverage processed by pulsed electric fields

peer-reviewedM.C. Pina-Pérez is grateful to CSIC for providing a DOCTOR contract linked to the INNPACTO project IPT-2011-1724-060000. This study was carried out with funds from BISOSTAD project PSE-060000-2009-003, Generalitat Valenciana I+D+I emergent research groups GV/2010/064 and CYCIT project AGL2010-22206-C02-01.Infants’ exposure (Nf ) to Cronobacter sakazakii via the consumption of infant-rich-inpolyphenols cocoa-milk-based beverages (CCX-M) treated with high-intensity pulsed electric fields (PEF) was evaluated. Monte Carlo simulation enabled the prediction of the variability in C. sakazakii load in beverages at the time of consumption to be estimated. Different scenarios (initial contamination levels; PEF treatment conditions; and time-temperature combinations of CCX-M beverages storage after treatment) were simulated. Cocoa addition and PEF treatment resulted in the most influential input factors to control bacterial final load. Cronobacter spp. exposure risk was reduced by a maximum of 100 times at 95% of iterations due to addition of cocoa at 5 g/100 mL, corresponding to scenario 3 (PEF: 15 kV/cm–3,000 μs; storage 120 h at 8 °C). Moreover, the probability of illness for a healthy population was reduced from 2.15 × 10-8, in the baseline scenario, to 4.78 × 10-10 due to cocoa addition and application of 15 kV/cm–3,000 μs PEF treatment.BISOSTAD projec