Reproductive Biology of Cero, Scomberomorus regalis, from the Coastal Waters of South Florida

Cero, Scomberomorus regalis, were collected off south Florida during 1980-81 to determine their reproductive biology. Spawning of cero occurs in coastal waters throughout most of the year with a peak in May. Males attain maturity at about 350 mm FL and females at about 380 mm FL. Fecundity estimates from 20 late maturing or ripe females ranged from 161,000 ova for a 380 mm fish weighing 558 g to 2,234,000 ova for a 800 mm fish weighing 4,944 g. Total weight better indicated fecundity than did fork length. The relationship between fecundity and total weight was expressed by the least square equation F = -1.079 x 10-1 + (4.342 x 10-4) TW. The mean number of ova per gram of fish weight was 362

Reproduction of Spanish Mackerel, Scomberomorus maculatus, from the Southeastern United States

Spanish mackerel, Scomberomorus maculatus, were collected during 1977-80 in the Gulf of Mexico and from North Carolina to south Florida during 1980-81 to describe their reproductive biology. The major spawning period extended from May to September in all areas and peaked during the spring and early summer. Most fish were mature at about 350 mm FL, but size at maturity varied between sexes and sampling areas. Males matured at a smaller size than females. Fecundity was estimated from 52 fish from all areas and ranged from about 100,000 eggs for a 328 mm (295 g) fish to 2,113,000 eggs for a 626 mm (2,415 g) fish. Fork length and total weight were equally good predictors of fecundity

Global marine bacterial diversity peaks at high latitudes in winter.

Genomic approaches to characterizing bacterial communities are revealing significant differences in diversity and composition between environments. But bacterial distributions have not been mapped at a global scale. Although current community surveys are way too sparse to map global diversity patterns directly, there is now sufficient data to fit accurate models of how bacterial distributions vary across different environments and to make global scale maps from these models. We apply this approach to map the global distributions of bacteria in marine surface waters. Our spatially and temporally explicit predictions suggest that bacterial diversity peaks in temperate latitudes across the world's oceans. These global peaks are seasonal, occurring 6 months apart in the two hemispheres, in the boreal and austral winters. This pattern is quite different from the tropical, seasonally consistent diversity patterns observed for most macroorganisms. However, like other marine organisms, surface water bacteria are particularly diverse in regions of high human environmental impacts on the oceans. Our maps provide the first picture of bacterial distributions at a global scale and suggest important differences between the diversity patterns of bacteria compared with other organisms

Heart and Ventilatory Measures in Crayfish During Copulation

Monitoring heart rate (HR) and ventilatory rate (VR) during defined sensory stimuli and during aggressive and submissive social interactions has provided additional information of a crayfish\u27s physiological state which is not achieved by behavioral observations. In this study, the HR and VR of crayfish were monitored before, during and after the act of copulation in both heterosexual partners. The female crayfish abruptly reduces HR and VR during copulation but the male maintains HR and VR. After separation from copulation the female HR and VR are elevated, potentially paying back the O2 debt. The tight relationship with HR and VR in direction of change indicates a potential neural coupling. These physiological changes in cardiac and respiratory systems suggest an autonomic-like regulation of HR and VR. How these neuronal functions are driven and regulated remains to be determined. Olfactory cues from the female to the male during copulation may be reduced by the reduction in VR in the female. These studies offer experimental paradigms for future neuronal and pharmacological investigations into autonomic regulation of HR and VR as well as the neural circuitry involved

Participant recruitment to FiCTION, a primary dental care trial – survey of facilitators and barriers

Objective To identify reasons behind a lower than expected participant recruitment rate within the FiCTION trial, a multi-centre paediatric primary dental care randomised controlled trial (RCT). Subjects (materials) and methods An online survey, based on a previously published tool, consisting of both quantitative and qualitative responses, completed by staff in dental practices recruiting to FiCTION. Ratings from quantitative responses were aggregated to give overall scores for factors related to participant recruitment. Qualitative responses were independently grouped into themes. Results Thirty-nine anonymous responses were received. Main facilitators related to the support received from the central research team and importance of the research question. The main barriers related to low child eligibility rates and the integration of trial processes within routine workloads. Conclusions These findings have directed strategies for enhancing participant recruitment at existing practices and informed recruitment of further practices. The results help provide a profile of the features required of practices to successfully screen and recruit participants. Future trials in this setting should consider the level of interest in the research question within practices, and ensure trial processes are as streamlined as possible. Research teams should actively support practices with participant recruitment and maintain enthusiasm among the entire practice team