Functional Resilience and Response to a Dietary Additive (Kefir) in Models of Foregut and Hindgut Microbial Fermentation In Vitro

Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized) was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs), lactate and ammonia concentration as well as lactic acid (LAB) and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks) effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefirpublishersversionPeer reviewe

Growth opportunities and the effect of corporate diversification on value

This paper provides empirical evidence of how a firm’s growth opportunities shape the diversification–value relationship on a sample of U.S. companies between 1998 and 2010. Our findings suggest that the negative relationship between diversification and a firm’s value may reverse at high levels of diversification, and that such a U-form diversification–value relation is partly mediated by a firm’s growth opportunities. Results are robust to various model specifications and after controlling for endogenous self-selection of the diversification decision

La medicina hospitalaria del siglo XXI. ¿Qué está cambiando?

El objetivo de este artículo es analizar los cambios que se han producido en el ejercicio de la medicina en los últimos años. La irrupción de la tecnología en la actividad diaria ha supuesto grandes modificaciones en nuestra manera de diagnosticar y tratar a los pacientes y es muy probable que este impacto sea mayor en el futuro. Esto ha supuesto grandes ventajas en cuanto a la obtención y manejo de la información de la enorme cantidad de datos clínicos y analíticos que se generan cada día. Por otra parte, la tecnología también ha modificado el quehacer diario de los profesionales sanitarios, con cambios en la dedicación a diferentes tareas y nuevos sistemas organizativos y de realización de trabajo en equipo. No se pretende ir en contra de estos avances tan notables, pero creo necesario este análisis con el fin de situarnos en el contexto actual en el que se ejercen las profesiones sanitarias y por lo tanto poder prever que nos depara el futuro. Finalmente, comentaré las perspectivas que se vislumbran en el horizonte cercano respecto al diagnóstico, cuidados y tratamiento de nuestros enfermos.The aim of this paper is to analyze the changes in medical profession in the last decades. Technology has irrupted in the daily activity and has brought many modifications in the way that doctors diagnose and treat patients, and it is expected that his impact will be even greater in the future. Technology has involved many advantages with respect to the recovery and management of the huge quantity of clinical and analytical data generated in health institutions. Furthermore, technology has changed the daily work of health professionals, with modifications in tasks and new organizational systems and team-based activities. We are not against these important advances, but it is advisable to analyze these changes with the objective of knowing our actual situation and to facilitate the adaptation to these changes in the future. Finally, I will discuss the future perspectives related to diagnosis, care and treatment of our patients

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H(2) sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy

The impact of economic policy uncertainty and monetary policy on R&D investment: An option pricing approach

Producción CientíficaThis paper adopts a real options approach to investigate the effects of economic policy uncertainty (EPU) and monetary policy on R&D investment. Using a panel of U.S. firms over the period 2000-2019, we show that higher (lower) EPU and contractionary (expansionary) monetary policy exert a positive (negative) and significant influence on R&D investment. Our findings shed light on the counter-intuitive behavior of R&D investments, which may help policymakers to anticipate such collateral effects.Ministerio de Ciencia, Innovación y Universidades (project PID2020-114797GB-I00

Capital budgeting practices in Spain

This paper seeks to shed further light on the capital budgeting techniques used by Spanish companies. Our paper posits that the gap between theory and practice might be related to the nature of sources of value and to the efficiency of mechanisms aligning managerial and shareholder incentives, rather than to resource restrictions or model misinterpretation. We analyze data from a survey conducted in 2011, the final sample comprising 140 non-financial Spanish firms. Our findings show a behaviour pattern similar to that reported in prior research for firms in other countries. Particularly noteworthy is that payback appears to be the most widely used tool, while real options are used relatively little. Our results confirm that size and industry are related to the frequency of use of certain capital budgeting techniques. Further, we find that the relevance of growth opportunities and flexibility is an important factor explaining the use of real optionsThis work has benefited from financial support from the Spanish Ministry of Science and Innovation (grant ref. ECO2011-29144-C03-01) and the Program of Advanced Human Capital Formation, Ministry of Education, Government of Chil