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Abstract: The medicinal plant Ocimum gratissimum L. (Labiatae) is widely encountered in the Northeast of Brasil where it is used to treat digestive problems. Its leaves have an essential oil (EOOG) content whose chemical composition varies according to the time of plant collection. We have compared the effects of the EOOG, collected at 08:00 a.m. (EOOG8) and at 12:00 a.m. (EOOG12), on the relaxation of guinea-pig isolated ileum. Both EOOG8 and EOOG12 (30–300μg/ml) reversibly relaxed the spontaneous tonus of the guinea-pig ileum in a concentration-dependent manner, with similar IC50 values (49.3 and 23.8μg/ml, respectively). The magnitude of the decrease in resting tonus was similar to that of the recognised smooth muscle relaxant papaverine. EOOG8 and EOOG12 relaxed 60mM KCl-precontracted preparations similarly (38.33±9.91μg/ml and 35.53±6.70), whereas a significantly more potent relaxant effect of EOOG12 compared to EOOG8 was observed when tissues were contracted using 10μM acetylcholine (IC50 values of 69.55±4.93 and 128.16±15.70μg/ml, respectively; ). The principal constituents of the essential oil, eugenol and cineole, also relaxed KCl-precontracted preparations, although they were less potent than EOOG, suggesting that they alone were not responsible for EOOG-induced relaxations. Our results show that the essential oil extracted from the leaves of O. gratissimum L., collected at different time periods, exerts significant relaxant effects on isolated guinea-pig ileum which may underlie the therapeutic action of the plant. [Copyright &y& Elsevier]

• Black-capped chickadees exposed to either male or female chick-a calls. • ZENK IEG expression was not different between sex of caller or sex of listener. • ZENK expression similar to previous behavioral data. In both humans and animals, biological differences between males and females has long been a topic of research. In songbirds, sexual dimorphisms can be seen in many species' plumage and heard in some species' songs. However, not all songbirds have such overt phenotypic sexual differences, leading to the question: are all vocalizations dimorphic? One of the most used and versatile vocalizations of the black-capped chickadee (Poecile atricapillus) is their namesake chick-a-dee call, that is produced by both sexes. This call is composed of four note types: A, B, C (together chick-a), and D (dee). Previous research has found that A notes contain information regarding the sex of the caller. However, chickadees do not categorize full chick-a-dee calls, or altered chick-a calls, based on the sex of the caller. Here we presented both male and female chickadees with altered chick-a calls (dee portion removed) of both sexes and measured the number of ZENK labeled cells in auditory nuclei. We found that calls produced by males and females had more ZENK labeled cells than the control condition; however, there was no significant difference in ZENK labeled cells between male and female listeners. Overall, our results suggest that black-capped chickadees do not perceive sexual differences in the production of chick-a calls. [ABSTRACT FROM AUTHOR]

• Subseasonal forecasts could provide insight into future risk to marine ecosystems. • Reducing fisheries bycatch in a changing ocean is a unique management challenge. • We integrate a species co-occurrence model with subseasonal oceanographic forecasts. • Spatiotemporal variability in bycatch risk is detectable at the weekly stage. • Study represents first step in the development of an ongoing bycatch avoidance tool. Over the past decade, substantial progress has been made in projecting and predicting the spatial distribution of many marine species at seasonal to multidecadal time scales. However, managers and fishers often need to make decisions at much shorter time scales. Subseasonal environmental forecasts, which generate predictions over one to several weeks, can now be combined with species-specific habitat preference data to create ecological forecasts that could facilitate dynamic spatial management. The development of such predictive tools could aid in identifying optimal times and areas for fishers to maximize target catch and avoid nontarget catch. Nontarget catch, or bycatch, can have numerous and potentially severe economic and ecological consequences. Here, we focus on a population of anadromous fish known collectively as river herring (alewife and blueback herring), as they are species of concern and are heavily impacted by bycatch. Using bottom trawl survey data from the Northeast US and subseasonal forecasts of sea surface temperature, we constructed a bycatch risk model to generate probabilistic predictions of river herring distributions in regions frequented by the US mid-water trawl fishery. Assessments of model skill showed that our ecological model performed well in predicting the distribution of river herring and that subseasonal forecasts were effective at 1-week timeframes. There was a clear seasonal effect on forecasted bycatch risk throughout the Northeast US, with particularly high risk in winter and spring months. Importantly, variability in risk was detectable at the weekly timescale and our model identified specific areas and times that fishers should avoid in order to decrease their likelihood of bycatch. The bycatch risk forecast developed in this study is a significant advance from near-real time forecasts and the foundation to build forecast systems by combining species co-occurrence models with subseasonal forecasts. As these subseasonal forecasts are available globally, this approach could be adapted to facilitate the management of other natural resource conflicts around the world. [ABSTRACT FROM AUTHOR]