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We build on previous research on the behavioral theory of the firm to examine the relationship between performance shortfalls and internationalization. We start from existing literature in claiming that the interplay between the aspirations of restoring performance and survival concerns leads to an inverted U-shaped relationship between a firm's performance shortfalls and its new internationalization. Our main contribution is to show that CEO duality moderates this relationship. Dual CEOs have a high control of the board that reduces oversight and increases their job security. This allows them to impose their risk preferences, thus embracing survival over aspirations. Our empirical analysis using a sample of Spanish listed firms from 1986 to 2010 provides support for our hypotheses.

Departamento de Reproducción Animal​., The guinea pig is an important meat production species in South America and a valuable animal model for the study of reproduction in humans and mammals. In vitro fertilisation (IVF) in this species is poorly developed mainly because of the limited accessibility to homologous (Ho) oocytes outside of South America. Thus, heterologous (He) IVF represents an alternative to improve the procedure. We aimed to evaluate the fertilising capacity of guinea pig sperm using two capacitation protocols in He IVF with murine oocytes. Spermatozoa were collected from the vas deferens of three guinea pigs and processed separately using two protocols: (A) spermatozoa were isolated by flushing the lumen of the vas deferens with 2 mL of 0.15 m NaCl and the sperm suspension was washed twice by centrifugation at 600 × g for 3 min and then incubated in minimal culture medium with 0.25 mM Na-pyruvate, 20.0 mM Na-lactate, and 5.56 mM glucose (MCM-PLG), during 2 h at 5% CO2 and 37°C; (B) the vas deferens was gently minced with fine scissors and spermatozoa suspended in 500 μL of HTF medium supplemented with 1% bopvine serum albumin (BSA), and incubated for 1 h at 5% CO2 and 37°C. Zona-intact murine oocytes collected from superovulated female mice were used for He IVF with spermatozoa capacitated through protocol A (HeA, n = 285) or B (HeB, n = 296) into drops of 500 µL of MCM-PLG with 2.7 mM KCl and 0.3% BSA or HTF medium, respectively. In parallel, Ho IVF (n = 243) and parthenogenesis (non-fertilised oocytes, n = 75) was performed in HTF medium. In vitro-matured oocytes were co-incubated for 5 h with 1 × 106 spermatozoa mL−1 and then presumptive zygotes or (parthenogenetic) oocytes were cultured in KSOM medium at 37°C and 5% CO2 to complete a total of 48 h of incubation. Sperm-oocyte interaction was assessed at 2.5 h post-insemination (hpi) by evaluating the number of bound spermatozoa. Presumptive zygotes were fixed and stained with Hoechst at 6, 18, and 22 hpi to assess polyspermy and pronuclear formation (PrF) by widefield fluorescence microscope with structured illumination. Cleavage rate was evaluated at 24 and 48 hpi. Data obtained from three replicates were analysed using one-way ANOVA. The number of bound sperm was similar between groups (Ho = 0.9 ± 0.1; HeA = 0.8 ± 0.1; HeB = 0.8 ± 0.1). No differences were seen in PrF at any time point (ranged from 24.4 ± 0.6 to 25.1 ± 0.9%) or cleavage rate between HeA or HeB IVF at 24 hpi (25.6 ± 0.9 and 25.7 ± 2.9%, respectively) or 48 hpi (24.2 ± 1.7 and 25.0 ± 1.3%). Homologous IVF was associated with higher percentages of PrF at 6 hpi (79.8 ± 2.1%) compared to HeA (24.4 ± 0.6%) and HeB (25.1 ± 0.9) IVF, and no polyspermy was detected. As expected, the cleavage rate at 24 or 48 hpi was higher (P < 0.05) in Ho (80.8 ± 0.9 and 81.4 ± 1.0, respectively) than He IVF. In addition, spontaneous parthenogenetic activation in mature unfertilised oocytes from mice at 24 and 48 hpi was observed (1.9 ± 1.9 and 2.6 ± 2.6%, respectively). In conclusion, He IVF is a promising method to assess the fertilising ability of guinea pig spermatozoa obtained from epididymis, revealing their ability to penetrate zona-intact murine oocytes, leading to hybrid embryo formation.

Cross-species communication, where signals are sent by one species and perceived by others, is one of the most intriguing types of communication that functionally links different species to form complex ecological networks. Global change and human activity can affect communication by increasing fluctuations in species composition and phenology, altering signal profiles and intensity, and introducing noise. So far, most studies on cross-species communication have focused on a few specific species isolated from ecological communities. Scaling up investigations of cross-species communication to the community level is currently hampered by a lack of conceptual and practical methodologies. Here, we propose an interdisciplinary framework based on information theory to investigate mechanisms shaping cross-species communication at the community level. We use plants and insects, the cornerstones of most ecosystems, as a showcase and focus on chemical communication as the key communication channel. We first introduce some basic concepts of information theory, then we illustrate information patterns in plant-insect chemical communication, followed by a further exploration of how to integrate information theory into ecological and evolutionary processes to form testable mechanistic hypotheses. We conclude by highlighting the importance of community-level information as a means to better understand the maintenance and workings of ecological systems, especially during rapid global change.

A brief review is made of the birth and evolution of the nonequilibrium potential(NEP) concept. As if providing a landscape for qualitative reasoning were not helpful enough, the NEP adds a quantitative dimension to the qualitative theory of differential equations and provides a global Lyapunov function for the deterministic dynamics. Here we illustrate the usefulness of the NEP to draw results on stochastic thermodynamics: the Jarzynski equality in the Wilson-Cowan model (a population-competition model of the neocortex) and a thermodynamic uncertainty relation(TUR) in the KPZ equation (the stochastic field theory of kinetic interface roughening). Additionally, we discuss system-size stochastic resonance in the Wilson-Cowan model and relevant aspects of KPZ phenomenology like the EW-KPZ crossover and the memory of initial conditions.

El conejo es una especie de ovulación inducida, en la que los estímulos sensoriales y neuroendocrinos parecen actuar en conjunto para inducir una oleada preovulatoria de (LH) (Barbe et al., 1973). En el caso de conejas inseminadas artificialmente (IA), la ovulación se suele inducir con una inyección intramuscular de análogos de (GnRH) (Rebollar et al., 1997). La tendencia, en la actualidad, es reducir todo lo posible la manipulación de la hembra y el gasto de consumibles (agujas y jeringuillas) en el momento de la IA. Una alternativa para esto podría ser la utilización de la neurotrofina β-NGF, que actúa como factor inductor de ovulación en camélidos (Ratto et al., 2013), incluida en la dosis seminal. Dado que recientemente hemos sintetizado la proteína recombinante de conejo (rrβNGF) (Sánchez-Rodríguez, 2018), el objetivo del presente trabajo ha sido evaluar el efecto de este factor incluido en la dosis seminal, sobre la liberación de LH hipofisaria y la fertilidad en conejas nulíparas.

Several million patients with liver cirrhosis suffer minimal hepatic encephalopathy (MHE), with mild cognitive and coordination impairments that reduce their quality of life and life span. Hyperammonaemia and peripheral inflammation act synergistically to induce these neurological alterations. We propose that MHE appearance is because of the changes in peripheral immune system, which are transmitted to brain, leading to neuroinflammation that alters neurotransmission leading to cognitive and motor alterations. We summarize studies showing that MHE in cirrhotic patients is associated with alterations in the immune system and that patients died with HE show neuroinflammation in cerebellum, with microglial and astrocytic activation and Purkinje cell loss. We also summarize studies in animal models of MHE on the role of peripheral inflammation in neuroinflammation induction, how neuroinflammation alters neurotransmission and how this leads to cognitive and motor alterations. These studies identify therapeutic targets and treatments that improve cognitive and motor function. Rats with MHE show neuroinflammation in hippocampus and altered NMDA and AMPA receptor membrane expression, which impairs spatial learning and memory. Neuroinflammation in cerebellum is associated with altered GABA transporters and extracellular GABA, which impair motor coordination and learning in a Y maze. These alterations are reversed by treatments that reduce peripheral inflammation (anti-TNF, ibuprofen), neuroinflammation (sulphoraphane, p38 inhibitors), GABAergic tone (bicuculline, pregnenolone sulphate) or increase extracellular cGMP (sildenafil or cGMP). The mechanisms identified would also occur in other chronic diseases associated with inflammation, aging and some mental and neurodegenerative diseases. Treatments that improve MHE may also be beneficial to treat these pathologies.

Both NGF and its receptors (TrkA and p75) have been demonstrated to be present in the female tract of some species. Our goal was to study if NGF and its receptors showed a differential expression in the reproductive tract in follicular (FP) and luteal phase (LP) and its relationship with blood estradiol (E2), progesterone (P4) and NGF serum concentrations in rabbit females. Ovary, uterus and oviduct of eCG treated animals were removed 48 h later (FP) or 7 days after GnRH injection (LP) and fixed. Blood samples were recovered at the same points and hormones determined by ELISA. Immunohistochemistry of paraffined samples with the ABC method was performed for NGF, TrkA and p75. NGF was expressed in oocytes of smaller follicles, and in granulose and theca cells in secondary follicles, stronger stained in the LF. Corpus luteum (CL) showed strong immunoreaction. Both oviduct and uterus expressed NGF in both phases. TrkA was highly expressed in all the structures studied, slightly more intense in the LP. However, p75 only was found in secondary and preantral follicles in the vascular layer between the thecas, and in the CL. Signal in the uterus and oviduct was scarce. Vessels were very immunoreactive for all the NGF system. Similar levels of E2 were found in both phases (44.85 ± 8.2 vs.45.70 ± 6.02 pg/ml) whereas P4 concentration was higher in the LF (0.67 ± 0.11 vs.22. 28 ± 3.73 ng/ ml; p < 0.05). NGF concentration was maintained during the cycle (345.42 ± 77.45 vs.301.72 ± 69.66 pg/ml) and no correlation was found with serum steroid levels. In conclusion, NGF system seems to have an important role during both phases in the rabbit female tract and is independent of hormonal environment. (Funds by AGL2015-65572-C2-2-R Grant and Predoctoral Contract UCM-Santander.)

El objetivo de este estudio fue evaluar las consecuencias de una restricción alimentaria moderada durante la gestación (40% del consumo voluntario) en un total de 116 conejas primíparas no lactantes (día 32 posparto). Los animales se distribuyeron al azar en 4 grupos experimentales atendiendo a la duración y periodo de la gestación en las que se aplicó la restricción de alimento: restringidas la primera semana (R07, n=30), la segunda y tercera semana (R721, n=28), las 3 primeras semanas (R021, n=29) o nunca (control, n=29). En la última semana de gestación, todas las conejas dispusieron de pienso ad libitum. Se estudiaron sus parámetros productivos y los de sus gazapos en el 20 cielo y se volvieron a inseminar 11 días después del 20 parto (3eT ciclo). En general, no se observó detrimento alguno en los parámetros de fertilidad y prolificidad de las conejas restringidas con respecto a las controles ni en ningún otro parámetro productivo. Únicamente se encontró una menor ganancia media diaria durante la lactación en los gazapos del grupo R07, que en el periodo de cebo aumentó de manera más unifonne que en el resto de los grupos, pero no consiguieron compensar y alcanzar el núsmo peso final. La restricción de alimento aplicada en segunda gestación tampoco afectó a los resultados productivos del 3 ciclo. Por tanto, podemos decir que este tipo de estrategias de manejo nutricional pueden servir de ayuda para evitar el engrasamiento de las conejas primíparas inseminadas en ritmos extensivos, sin deterioro de su productividad en sus primeros ciclos.

Maternal nutritional disorders during pregnancy can modify placental vascularization and therefore, fetal development. The aim of this work was to assess the effect of a feed restriction of 60% of the nutritional requirements during pregnancy on fetoplacental development, placental efficiency (fetal/placental weight) and expression of vascular endothelial growth factor (VEGF) in the rabbit. Multiparous pregnant rabbits were fed ad libitum (C; n = 17) or food restricted (R021, n = 25) from day (D) 0 to D21. On D28, 11 dams were euthanized to study fetoplacental features and the rest (n = 31) were used to assess perinatal survival and birth weight. Immunohistochemical studies of paraffined placentae (ABC method) was performed for VEGF. No differences were found in the number of viable fetuses between C and R021 groups (11.6 ± 2.9 vs. 12.0 ± 2.0). However, fetuses of C group showed higher size (thoracic diameter: 20.5 ± 2.8 vs. 19.1 ± 1.8 mm, occipital-nasal length: 29.0 ± 1.4 vs. 27.9 ± 1.4 mm); total weight (39.2 ± 7.3 vs. 34.7 ± 5–9 g), and separated head and body weights (9.1 ± 1.5 vs. 8.1 ± 1.1 and 29.3 ± 6.0 vs. 25.6 ± 4.8 g, respectively) than R021 (p < 0.05). Placental efficiency was lower in R021 than in C group (p < 0.05). VEGF was mainly immunolocalized in endothelial cells in labyrinth zone in both groups being slightly intensive in C group. Mean number of born alive per doe (10.4 ± 3.0 vs. 12.3 ± 3.1) and their weight (59.1 ± 9.8 vs. 56.4 ± 6.8 g) were similar between groups. In conclusion, maternal feed restriction seems to modulate VEGF expression, placental efficiency and fetal development in the rabbit. These effects were not reflected in a low body weight at parturition. (Funds by AGL2015-65572-C2.)

En el plasma seminal (PS) de algunas especies, tanto de ovulacion inducida como espontanea, se ha descrito la presencia de un factor inductor de la ovulacion (FIO) (Adams y col., 2005). Recientemente se ha descubierto que se trata del factor de crecimiento nervioso (NGF) (Ratto y col., 2012), cuyo precursor es el pro-NGF que tiene un peso molecular -60 kDa y varias isoformas en el rango entre 16-60 kDa (Paoletti y col., 2006). Ademas, se ha descrito la presencia del receptor de alta afinidad de esta proteina (TrkA) solo en prostata, testiculo y glandula seminal del tracto reproductor de conejo (Maranesi y col., 2015), pero no en otras importantes estructuras con un papel esencial en la produccion de PS y en la espermatogenesis. El objetivo del presente trabajo fue localizar por inmunohistoquimica el receptor TrkA en la glandula bulbouretral y en el epididimo e identificar por espectrometria de masas (MALDI-TOF) la presencia de esta proteina, en una fraccion purificada del PS del conejo, que previamente habia sido identificada por western blot (WB).