Limpets and barnacles are important components of intertidal assemblages worldwide. This study examines the effects of barnacles on the foraging behaviour of the limpet Patella vulgata, which is the main algal grazer in the North-west Atlantic. The behaviour of limpets on a vertical seawall on the Isle of Man (UK) was investigated using autonomous radio-telemetry, comparing their activity patterns on plots characterized by dense barnacle cover and plots from which the barnacles had been removed. Limpet behaviour was investigated at mid-shore level, but two different elevations were considered. This experiment revealed a significant effect of barnacle cover on the activity of P. vulgata. Limpets on smooth surfaces spent a greater proportion of total time active than did limpets on barnacles. Movement activity was also greater in areas that were lower down in the tidal range. In general, limpets were either predominantly active during diurnal high or nocturnal low tides and always avoided nocturnal high tides. Individuals on barnacles at the higher elevation concentrated their activity during nocturnal low water. All the other groups of limpets (smooth surfaces on the upper level and all individuals on the lower shore) had more excursions centred around daylight hours with an equal distribution of activity between periods of low and high water. Inter-individual variability was, however, pronounced.

The tropical dry deciduous forest (TDF) of the semi-arid region of Bajio in Mexico is dominated by successional communities, in which Lysiloma microphyllum is irregularly distributed, however the environmental factors influencing its establishment have been poorly studied. We conducted field experiments to isolate the impact of three factors on the early life-history stages of this tree. Over a 2-y period, we monitored the effects of (1) predation, (2) understorey light and (3) aspect on germination, seed-to-seedling transition (establishment) and seedling survival, and we found that open space negatively affected germination (14.9 ± 1.5% vs 96 ± 1.5% in shade; mean ± SE), while shade increased seedling establishment and survival (36.9 ± 8.2% vs 4.7 ± 3.8% in open sites). Predation decreased survival and was strongest in open conditions (0 vs 62.7 ± 9.4% in shaded exclosures). In contrast, aspect had little influence on germination and survival. The results suggest that shaded microsites positively affect the early life stages of L. microphyllum, a key process in TDF recovery.

This study examines the interplay between individual and social–developmental factors in the development of positive functioning, substance use problems, and mental health problems. This interplay is nested within positive and negative developmental cascades that span childhood, adolescence, the transition to adulthood, and adulthood. Data are drawn from the Seattle Social Development Project, a gender-balanced, ethnically diverse community sample of 808 participants interviewed 12 times from ages 10 to 33. Path modeling showed short- and long-term cascading effects of positive social environments, family history of depression, and substance-using social environments throughout development. Positive family social environments set a template for future partner social environment interaction and had positive influences on proximal individual functioning, both in the next developmental period and long term. Family history of depression adversely affected mental health functioning throughout adulthood. Family substance use began a cascade of substance-specific social environments across development, which was the pathway through which increasing severity of substance use problems flowed. The model also indicated that adolescent, but not adult, individual functioning influenced selection into positive social environments, and significant cross-domain effects were found in which substance-using social environments affected subsequent mental health.

Realization that hard coastal infrastructures support lower biodiversity than natural habitats has prompted a wealth of research seeking to identify design enhancements offering ecological benefits. Some studies showed that artificial structures could be modified to increase levels of diversity. Most studies, however, only considered the short-term ecological effects of such modifications, even though reliance on results from short-term studies may lead to serious misjudgements in conservation. In this study, a seven-year experiment examined how the addition of small pits to otherwise featureless seawalls may enhance the stocks of a highly-exploited limpet. Modified areas of the seawall supported enhanced stocks of limpets seven years after the addition of pits. Modified areas of the seawall also supported a community that differed in the abundance of littorinids, barnacles and macroalgae compared to the controls. Responses to different treatments (numbers and size of pits) were species-specific and, while some species responded directly to differences among treatments, others might have responded indirectly via changes in the distribution of competing species. This type of habitat enhancement can have positive long-lasting effects on the ecology of urban seascapes. Understanding of species interactions could be used to develop a rule-based approach to enhance biodiversity.

Purpose: The 2007 Institute of Medicine report entitled Emergency Medical Services at the Crossroads identified a need for the establishment of physician subspecialty certification in emergency medical services (EMS). The purpose of this study was to identify and explore the evolution of publications that define the role of the physician in EMS systems in the United States.

Methods: Three comprehensive searches were undertaken to identify articles that define the physician's role in the leadership, clinical development, and practice of EMS. Independent reviewers then evaluated these articles to further determine whether the articles identified the physician's role in EMS. Then, identified articles were classified by the type of publication in order to evaluate the transition from a non-peer reviewed to peer-reviewed literature base and an analysis was performed on the differences in the growth between these two groups. In addition, for the peer-reviewed articles, an analysis was performed to identify the proportion of articles that were quantitative versus qualitative in nature.

Results: The comprehensive review identified 1,504 articles. Ninety articles were excluded due to lack of relevance to the US. The remaining 1,414 articles were reviewed, and 194 papers that address the physician's role within EMS systems were identified; 72 additional articles were identified by hand search of references for a total of 266 articles. The percentage of peer-reviewed articles has increased steadily over the past three decades. In addition, the percentage of quantitative articles increased from the first decade to the second and third decades.

Conclusions: This comprehensive review demonstrates that over the past 30 years an evidence base addressing the role of the physician in EMS has developed. This evidence base has steadily evolved to include a greater proportion of peer-reviewed, quantitative literature.

There is clear evidence that marine reserves can be used as effective tools to foster the recovery of disturbed ecosystems. In the Azores, intense exploitation of the patellid limpets Patella candei and P. aspera has led to a rapid decline in their populations and subsequent collapse of the fishery in 1985. In 1993, legislation was passed to protect limpets, including the establishment of limpet protected zones (LPZs) where harvesting was completely prohibited. Outside LPZs, a seasonal fishing closure prohibited the harvesting of limpets from October to May. Here we examine the effect of such measures 16 years after they were put into practice. In each of the 3 years examined, limpet density, biomass and size were generally similar both inside and outside the LPZs. In addition, there were clear signs of exploitation as most individual limpets inside the LPZ were smaller than the legal catch size suggesting that illegal harvesting was taking place. Observations confirmed that illegal harvesting of limpets was common both inside and outside LPZs. Lack of enforcement of regulations is therefore a likely reason for the failure of legislation to protect limpet populations and facilitate stock recovery.

The age and population structure of Parablennius sanguinolentus parvicornis (Valenciennes) (Pisces: Blenniidae) from the Azores have been studied. Total length and weight relationships are given for each sex. Age study was based on otoliths readings. The von Bertalanffy growth function was applied to describe the growth in total length with age. At the end of the first year mean (±SD) total length was significantly different in males (7.1 ±1.5 cm) and females (6.1 ±1.2 cm). One-year-old males participate in reproduction as satellites, whereas females do not. The implications of this in early growth rate of the males is discussed. During the two most important months of the reproductive season (i.e. June and July), the sex ratio was significantly biased towards males, particularly in the larger size classes.

Prior to the late 1960s second language acquisition was thought to be a relatively uninteresting phenomenon; it involved transferring grammatical properties already activated in the first language (L 1) onto second language (L 2) vocabulary. Successful L 2 learners were those who could capitalise on the similarities between the L 1 and the L 2, and eradicate the differences; and successful language teaching involved training learners to overcome the L 1-L 2 differences. Today, perceptions of second language acquisition are more sophisticated and nuanced. Second language acquisition researchers are interested in questions bearing not only on the influence of the L 1, but also on the degree of systematicity in L 2 development, the role that L 1, but also on the degree of systematicity in L 2 development, the role that conscious knowledge plays, the sources of variability in second language speaker performance, the ultimate levels of success achieved by L 2 learners of different ages, and individual differences between learners. The purpose of this article is to present what the authors believe to be some of the key issues which characterise current second language acquisition research, and to consider those issues within the specific context of the acquisition of French as second language.