12 research outputs found
Bioenergetics and Trophic Impacts of Invasive Indo-Pacific Lionfish
Indo-Pacific lionfish, Pterois volitans and Pterois miles, are non-native marine fish with established populations in the western North Atlantic Ocean and Caribbean Sea. Rapid population growth threatens native fish communities and they are considered invasive species. A bioenergetics model was developed for lionfish and applied to populations inhabiting the western North Atlantic Ocean to model the potential impact of these predators on native reef ecosystems. Model parameters were derived by laboratory evaluation of consumption and respiration rates from 14 to 32° C and fish size ranging from 19 to 400 g. The model was calibrated with laboratory growth and consumption data, and model performance was analyzed to evaluate the parameters most sensitive to error. The optimal temperature for lionfish consumption is 29.8° C. Energy allocated to gamete production reduces female lionfish growth rate compared to males and limits maximum body size. Based on the environmental conditions and observed growth, daily consumption estimates of 393 lionfish [dot in center of line] ha-1 could remove up to 2.186 kg prey [dot in center of line] d-1 during the summer in the Bahamas. The corroborated model is a useful tool for examining the influence of temperature on predation rates, and exploring the interaction between lionfish and prey.  M.S
The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats
The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well
Bioenergetics and Trophic Impacts of Invasive Indo-Pacific Lionfish
Indo-Pacific lionfish Pterois volitans and Pterois miles are non-native marine fish with established populations in the western North Atlantic Ocean and Caribbean Sea. Rapid population growth threatens native fish communities and they are considered invasive species. A bioenergetics model was developed for lionfish and applied to populations inhabiting the western North Atlantic Ocean to model the potential impact of these predators on native reef ecosystems. Model parameters were derived by laboratory evaluation of consumption and respiration rates from 14 to 32° C and fish size ranging from 19 to 400 g. The model was calibrated with laboratory growth and consumption data and model performance was analyzed to evaluate the parameters most sensitive to error. The optimal temperature for lionfish consumption is 29.8° C. Energy allocated to gamete production reduces female lionfish growth rate compared to males and limits maximum body size. Based on the environmental conditions and observed growth daily consumption estimates of 393 lionfish [dot in center of line] ha-1 could remove up to 2.186 kg prey [dot in center of line] d-1 during the summer in the Bahamas. The corroborated model is a useful tool for examining the influence of temperature on predation rates and exploring the interaction between lionfish and prey.
Reproduction, larviculture and early development of the Bluebanded goby, Lythrypnus dalli, an emerging model organism for studies in evolutionary developmental biology and sexual plasticity
The Bluebanded goby, Lythrypnus dalli, is a popular ornamental aquarium species and a key organism for the study of several fundamental biological questions, most notably reversible sex change in adults. To maximize the tractability of this species as an emerging model system, it is essential to have an optimized propagation system and a detailed developmental staging scheme. One limitation to the larviculture of L. dalli is the relatively small size of the larvae, which makes the transition from yolk to feeding challenging. We developed a protocol and successfully reared three generations of L. dalli in the laboratory. The protocol contains several key innovations for the rearing of diminutive fish larvae, including tank design and co-culturing of microalgae (Isochrysis galbana) with copepods (Parvocalanus sp.) in the larval rearing tanks. In addition, we describe the embryonic and larval development of L. dalli under controlled conditions and in comparison with the model organism Danio rerio. We found that at 21°C L. dalli larvae hatch in 4 days, reach flexion in 18-25 days and are sexually mature by 3 months. Overall, the embryonic development of L. dalli is remarkably similar to D. rerio with several striking differences, including the position and shape of the blastomere, size of the neuromasts and corresponding cupula, and relative timing of pigmentation and brain subdivision. The ability to rear this species in captivity is a valuable tool that could be utilized for a variety of similarly diminutive species and to address a greater breadth and depth of biological questions
Perceived Control Across the Adult Lifespan: Longitudinal Changes in Global Control and Daily Stressor Control (in press, preprint)
Perceived control is an important psychosocial resource for health and wellbeing across the lifespan. Global control (i.e., overall perceived control) decreases over time in studies following people every few years to upwards of 10 years. Changes across wider intervals of the lifespan, however, have yet to be examined. Further, how perceived control changes for specific aspects of daily life, such as stressors, remains comparatively less clear. Using data from the MIDUS National Study of Daily Experiences (NSDE, N=1,940, M=56.25 years, SD=12.20, 57% Female), we examined longitudinal changes in global control across 20 years and daily stressor control across 10 years. Global control was assessed in the first wave of the NSDE (~1996). In follow-up waves, conducted in ~2008 and ~2017, participants again reported their global control, but also reported their perceived control over stressors they experience across eight consecutive days. Longitudinal analyses revealed differential change trajectories for global control across 20 years and stressor control across 10 years (p’s<.001). Global control declined for younger and older adults, but stayed relatively stable for individuals in midlife. The rate of decline in daily stressor control was steeper than the decline in global control and did not vary by age at baseline. In addition, declines were amplified among individuals with higher global control at baseline. Results suggest that daily stressor control is a specific aspect of control beliefs that follows a different rate of change than global control
Potential transfer of aquatic organisms via ballast water with a particular focus on harmful and non-indigenous species: A survey from Adriatic ports
Ballast water discharges may cause negative impacts to aquatic ecosystems, human health and economic activities by the introduction of potentially harmful species. Fifty untreated ballast water tanks, ten in each port, were sampled in four Adriatic Italian ports and one Slovenian port. Salinity, temperature and fluorescence were measured on board. Faecal indicator bacteria (FIB), phyto- and zooplankton were qualitatively and quantitatively determined to identify the species assemblage arriving in ballast water. FIB exceeded the convention standard limits in 12% of the sampled tanks. Vibrio cholerae was not detected. The number of viable organisms in the size groups (minimum dimension) <50 and ≥10 μm and ≥50 μm resulted above the abundances required from the Ballast Water Management Convention in 55 and 86% of the samples, respectively. This is not surprising as unmanaged ballast waters were sampled. Some potentially toxic and non-indigenous species were observed in both phyto- and zooplankton assemblages
Studies on picophytoplankton in the southern Gulf of Mexico: recognition of picoprokaryotes and abundances of picophytoplankton during "dry season"
The abundance and distribution of total autotrophic picophytoplankton (PFP), temperature, salinity, PAR, and chlorophyll a were determined in two presumably contrasting environments: (1) two coastal areas (close to the mouths of three rivers), and (2) one oceanic area (Campeche Canyon), of the southern Gulf of Mexico, during the "dry season" (June-July, 2004). The picoprokaryotes Prochlorococcus and Synechococcus were identified by TEM, whereas Synechococcus and picoeukaryotes populations were also recognized by flow cytometry. The highest PFP abundance (1.67×105 cells ml-1) was found in shallow waters (~10 m depth) around the Grijalva-Usumacinta river mouth, followed by that found at a station close to the Coatzacoalcos River (1.19×105 cells ml-1); PFP abundances in the Campeche Canyon were usually lower (maximum 1.53×104 cells ml-1). Greater variability in PFP abundances was found in coastal stations than in oceanic waters, and weak relationships appeared between the patterns of chlorophyll a and PFP abundance. Peaks of PFP were detected in both coastal and more oceanic areas, but in the Campeche Canyon they were located deeper (60 m), relatively closer to the deep maximum of chlorophyll (located at about 75 m). Results suggest that PFP populations include a substantial photosynthetic component in both coastal and oceanic waters of the southern Gulf of Mexico
A comparative study of the risk profile of hemodialysis patients in a for profit network and in two regional registries of the Italian Society of Nephrology
In 2013, the Italian Society of Nephrology joined forces with Nephrocare-Italy to create a clinical research cohort of patients on file in the data-rich clinical management system (EUCLID) of this organization for the performance of observational studies in the hemodialysis (HD) population. To see whether patients in EUCLID are representative of the HD population in Italy, we set out to compare the whole EUCLID population with patients included in the regional HD registries in Emilia-Romagna (Northern Italy) and in Calabria (Southern Italy), the sole regions in Italy which have systematically collected an enlarged clinical data set allowing comparison with the data-rich EUCLID system. An analysis of prevalent and incident patients in 2010 and 2011 showed that EUCLID patients had a lower prevalence of coronary heart disease, peripheral vascular disease, heart failure, valvular heart disease, liver disease, peptic ulcer and other comorbidities and risk factors and a higher fractional urea clearance (Kt/V) than those in the Emilia Romagna and Calabria registries. Accordingly, survival analysis showed a lower mortality risk in the EUCLID 2010 and 2011 cohorts than in the combined two regional registries in the corresponding years: for 2010, hazard ratio (HR) EUCLID vs. Regional registries: 0.80 [95% confidence interval: 0.71–0.90]; for 2011, HR: 0.76 [0.65–0.90]. However, this difference was nullified by statistical adjustment for the difference in comorbidities and risk factors, indicating that the longer survival in the EUCLID database was attributable to the lower risk profile of patients included in that database. This preliminary analysis sets the stage for future observational studies and indicates that appropriate adjustment for difference in comorbidities and risk factors is needed to generalize to the Italian HD population analyses based on the data-rich EUCLID database
Correction to: Tocilizumab for patients with COVID-19 pneumonia. The single-arm TOCIVID-19 prospective trial (Journal of Translational Medicine, (2020), 18, 1, (405), 10.1186/s12967-020-02573-9)
Following publication of the original article [1] the authors identified that the collaborators of the TOCIVID-19 investigators, Italy were only available in the supplementary file. The original article has been updated so that the collaborators are correctly acknowledged. For clarity, all collaborators are listed in this correction article