Trends in hydroidomedusan research from 1911 to 1997

The papers on hydroidomedusae published from 1911 to 1997 total 10,934. They have been assigned to the following categories: faunistics and systematics; sub-organismal biology; ecology; evolution; life cycles; paleontology. The general trend, comprising all papers, can be divided into four time intervals: the first (1911-1939) with an average of sixty papers/year and with a slight decrease due to First World War; the second one (1940-1947), with an average of 38 papers/year, marked by a dramatic decrease coinciding with Second World War; the period 1948-1991 shows a steady increase until the mid-Seventies, when a small decrease occurred, followed by an increasing trend reaching its apex in the late Eighties-early Ninenties with a record of 296 papers in 1991 and with an average of 175 papers/year; the period 1992 1997, with an average of 178 papers/year, is marked by a sharp decrease, reaching the values of the mid Sixties. The most important category in terms of number of papers is sub-organismal biology, followed by faunistics and systematics. Systematic studies dictated the trend in the first decades of the century, whereas sub-organismal ones are prevalent from the Sixties onwards. Faunistic and systematic-taxonomic papers have a steady trend of production, with just a slight decrease over these last years. The formerly leading countries in systematics (UK, USA, France) are now almost inactive in this discipline, whereas countries with little or no tradition in this field (such as Spain) are taking the leadership

Mapping wildland-urban interfaces at large scales integrating housing density and vegetation aggregation for fire prevention in the South of France

Every year, more than 50,000 wildland fires affect about 500,000 ha of vegetation in southern European countries, particularly in wildland-urban interfaces (WUI). This paper presents a method to characterize and map WUIs at large scales and over large areas for wildland fire prevention in the South of France. Based on the combination of four types of building configuration and three classes of vegetation structure, 12 interface types were classified. Through spatial analysis, fire ignition density and burned area ratio were linked with the different types of WUI. Among WUI types, isolated WUIs with the lowest housing density represent the highest level of fire risk

Temporal variability and spatial dynamics of CO2 and CH4 concentrations and fluxes in the Zambezi River system

Spanning over 2900 km in length and with a catchment of approximately 1.4 million km2, the Zambezi River is the fourth largest river in Africa and the largest flowing into the Indian Ocean from the African continent. Yet, there is surprisingly little or no information on carbon (C) cycling in this large river system. As part of a broader study on the riverine biogeochemistry in the Zambezi River basin, we present here mainstream dissolved CO2 and CH4 data collected during 2012 and 2013 over two climatic seasons (dry and wet) to constrain the interannual variability, seasonality and spatial heterogeneity of partial pressure of CO2 (pCO2) and CH4 concentrations and fluxes along the aquatic continuum, in relation to physico-chemical parameters (temperature, conductivity, oxygen, and pH) and various carbon pools (dissolved and particulate, organic and inorganic carbon, total alkalinity, primary production, respiration and net aquatic metabolism). Both pCO2 and CH4 variability was high, ranging from minimal values of 150 ppm and 7 nM, respectively, mainly in the two large reservoirs (the Kariba and the Cabora Bassa characterized by high pH and oxygen and low DOC), up to maximum values of 12,500 ppm and 12,130 nM, CO2 and CH4, respectively, mostly below floodplains/wetlands (low pH and oxygen levels, high DOC and POC concentrations). The interannual variability was relatively large for both CO2 and CH4 (mean pCO2: 2350 ppm in 2013 vs. 3180 ppm in 2013; mean CH4: 600 nM in 2012 vs. 1000 nM in 2013) and significantly higher (up to two fold) during wet season compared to dry season closely linked to distinct seasonal hydrological characteristics. Overall, no clear pattern was observed along the longitudinal gradient as river CO2 and CH4 concentrations are largely influenced by the presence of floodplains/wetlands, anthropogenic reservoirs or natural barriers (waterfalls/ rapids). Following closely the concentration patterns, river CO2 and CH4 mean fluxes of 3440 mg C-CO2 m-2 d-1 and 50 mg C-CH4 m-2 d-1, respectively, were well within the range of literature data for tropical river systems, while the two reservoirs were a sink of atmospheric CO2 (-240 mg C-CO2 m-2 d-1) and a low CH4 source (4 mg C-CH4 m-2 d-1)

Benthic Carbon fixation and cycling in diffuse hydrothermal and background sediments in the Bransfield Strait, Antarctica

Sedimented hydrothermal vents are likely to be widespread compared to hard substrate hot vents. They host chemosynthetic microbial communities which fix inorganic carbon (C) at the seafloor, as well as a wide range of macroinfauna, including vent-obligate and background non-vent taxa. There are no previous direct observations of carbon cycling at a sedimented hydrothermal vent. We conducted 13C isotope tracing experiments at three sedimented sites in the Bransfield Strait, Antarctica, which showed different degrees of hydrothermalism. Two experimental treatments were applied, with 13C added as either algal detritus (photosynthetic C), or as bicarbonate (substrate for benthic C fixation). Algal 13C was taken up by both bacteria and metazoan macrofaunal, but its dominant fate was respiration, as observed at deeper and more food-limited sites elsewhere. Rates of 13C uptake and respiration suggested that the diffuse hydrothermal site was not the hot spot of benthic C cycling that we hypothesised it would be. Fixation of inorganic C into bacterial biomass was observed at all sites, and was measurable at two out of three sites. At all sites, newly fixed C was transferred to metazoan macrofauna. Fixation rates were relatively low compared with similar experiments elsewhere; thus, C fixed at the seafloor was a minor C source for the benthic ecosystem. However, as the greatest amount of benthic C fixation occurred at the “Off Vent” (non-hydrothermal) site (0.077±0.034 mg C m−2 fixed during 60 h), we suggest that benthic fixation of inorganic C is more widespread than previously thought, and warrants further study

Approaches to the ethology of hydroids and medusae (Cnidaria, Hydrozoa)

The behavioural patterns of 26 species of Antho- and Leptomedusae (with or without medusa stage) were investigated by video recordings. The analysed activities were: answers to mechanical stimuli, prey capture and ingestion, digestion, egestion, and swimming. The quantity of behavioural patterns identified in the small number of hydrozoan diversity studied so far is sufficient to demonstrate that these supposedly "simple" animals have evolved a complex array of responses to both external and internal stimuli

Active vitamin D (1,25-dihydroxyvitamin D) and bone health in middle-aged and elderly men: the European male aging study (EMAS)

<p>Context: There is little information on the potential impact of serum 1,25-dihydroxyvitamin D [1,25(OH)2D] on bone health including turnover.</p> <p>Objective: The objective of the study was to determine the influence of 1,25(OH)2D and 25-hydroxyvitamin D [25(OH)D] on bone health in middle-aged and older European men.</p> <p>Design, Setting, and Participants: Men aged 40–79 years were recruited from population registers in 8 European centers. Subjects completed questionnaires that included questions concerning lifestyle and were invited to attend for quantitative ultrasound (QUS) of the heel, assessment of height and weight, and a fasting blood sample from which 1,25(OH)2D, 25(OH)D, and PTH were measured. 1,25(OH)2D was measured using liquid chromatography tandem mass spectrometry. Bone markers serum N-terminal propeptide of type 1 procollagen (P1NP) and crosslinks (β-cTX) were also measured. Dual-energy x-ray absorptiometry (DXA) of the hip and lumbar spine was performed in 2 centers.</p> <p>Main Outcome Measure(s): QUS of the heel, bone markers P1NP and β-cTX, and DXA of the hip and lumbar spine were measured.</p> <p>Results: A total of 2783 men, mean age 60.0 years (SD 11.0) were included in the analysis. After adjustment for age and center, 1,25(OH)2D was positively associated with 25(OH)D but not with PTH. 25(OH)D was negatively associated with PTH. After adjustment for age, center, height, weight, lifestyle factors, and season, 1,25(OH)2D was associated negatively with QUS and DXA parameters and associated positively with β-cTX. 1,25(OH)2D was not correlated with P1NP. 25(OH)D was positively associated with the QUS and DXA parameters but not related to either bone turnover marker. Subjects with both high 1,25(OH)2D (upper tertile) and low 25(OH)D (lower tertile) had the lowest QUS and DXA parameters and the highest β-cTX levels.</p> <p>Conclusions: Serum 1,25(OH)2D is associated with higher bone turnover and poorer bone health despite being positively related to 25(OH)D. A combination of high 1,25(OH)2D and low 25(OH)D is associated with the poorest bone health.</p&gt

Active vitamin D (1,25-dihydroxyvitamin D) and bone health in middle-aged and elderly men: the European male aging study (EMAS)

<p>Context: There is little information on the potential impact of serum 1,25-dihydroxyvitamin D [1,25(OH)2D] on bone health including turnover.</p> <p>Objective: The objective of the study was to determine the influence of 1,25(OH)2D and 25-hydroxyvitamin D [25(OH)D] on bone health in middle-aged and older European men.</p> <p>Design, Setting, and Participants: Men aged 40–79 years were recruited from population registers in 8 European centers. Subjects completed questionnaires that included questions concerning lifestyle and were invited to attend for quantitative ultrasound (QUS) of the heel, assessment of height and weight, and a fasting blood sample from which 1,25(OH)2D, 25(OH)D, and PTH were measured. 1,25(OH)2D was measured using liquid chromatography tandem mass spectrometry. Bone markers serum N-terminal propeptide of type 1 procollagen (P1NP) and crosslinks (β-cTX) were also measured. Dual-energy x-ray absorptiometry (DXA) of the hip and lumbar spine was performed in 2 centers.</p> <p>Main Outcome Measure(s): QUS of the heel, bone markers P1NP and β-cTX, and DXA of the hip and lumbar spine were measured.</p> <p>Results: A total of 2783 men, mean age 60.0 years (SD 11.0) were included in the analysis. After adjustment for age and center, 1,25(OH)2D was positively associated with 25(OH)D but not with PTH. 25(OH)D was negatively associated with PTH. After adjustment for age, center, height, weight, lifestyle factors, and season, 1,25(OH)2D was associated negatively with QUS and DXA parameters and associated positively with β-cTX. 1,25(OH)2D was not correlated with P1NP. 25(OH)D was positively associated with the QUS and DXA parameters but not related to either bone turnover marker. Subjects with both high 1,25(OH)2D (upper tertile) and low 25(OH)D (lower tertile) had the lowest QUS and DXA parameters and the highest β-cTX levels.</p> <p>Conclusions: Serum 1,25(OH)2D is associated with higher bone turnover and poorer bone health despite being positively related to 25(OH)D. A combination of high 1,25(OH)2D and low 25(OH)D is associated with the poorest bone health.</p&gt