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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2007.03.010 Byline: Steve W. Ross, Andrea M. Quattrini Keywords: Deep-sea corals; Southeastern USA; Blake Plateau; Deep-reef fishes; Lophelia Abstract: Deep-sea or cold-water corals form substantial habitat along many continental slopes, including the southeastern United States (SEUS). Despite increasing research on deep coral systems and growing appreciation of their importance to fishes, quantitative data on fish communities occupying these ecosystems are relatively lacking. Our overall goals were to document the fish species and their relative abundances and to describe the degree of general habitat specificity of the fishes on and around deep coral habitats on the SEUS slope. From 2000 to 2006, we used the Johnson-Sea-Link (JSL) submersible (65 dives, 366-783m), supplemented with otter trawls (33 tows, 365-910m) to document fishes and habitats from off North Carolina to east-central Florida. Eight areas with high concentrations of deep-sea corals were surveyed repeatedly. Three general habitat types (prime reef, transition reef, and off reef) were defined to determine large-scale habitat use patterns. Throughout the area, at least 99 fish species were identified, many (19%) of which yielded new distributional data. Most species observed with the JSL were on prime reef (n=50) and transition reef (n=42) habitats, but the off reef habitat supported a well developed, but different fauna (n=25 species). Prime reef was characterized by Laemonema melanurum (21% of total), Nezumia sclerorhynchus (17% of total), Beryx decadactylus (14% of total), and Helicolenus dactylopterus (10% of total). The off reef areas were dominated by Fenestraja plutonia (19% of total), Laemonema barbatulum (18% of total), Myxine glutinosa (8% of total), and Chlorophthalmus agassizi (7% of total). Transition habitat exhibited a mixture of species that were also found on either prime reef or off reef habitats. Nezumia sclerorhynchus was the most abundant (25% of total) transition habitat species, followed by L. barbatulum (16% of total) and L. melanurum (14% of total). Several species (e.g., Anthias woodsi, B. decadactylus, Conger oceanicus, and Dysommina rugosa) demonstrated specificity to deep-reef habitats, while others (e.g., C. agassizi, Benthobatis marcida, F. plutonia, and Phycis chesteri) were always more common away from reefs. In addition to new distributional data, we provide behavioral and biological observations for dominant species. Author Affiliation: University of North Carolina Wilmington, Center for Marine Science, 5600 Marvin K. Moss Lane, Wilmington, NC 28409, USA Article History: Received 2 December 2006; Revised 12 March 2007; Accepted 14 March 2007

Recent investigations of demersal fish communities in deepwater (>50 m) habitats have considerably increased our knowledge of the factors that influence the assemblage structure of fishes across mesophotic to deep-sea depths. While different habitat types influence deepwater fish distribution, whether different types of rugged seafloor features provide functionally equivalent habitat for fishes is poorly understood. In the northeastern Caribbean, different types of rugged features (e.g., seamounts, banks, canyons) punctuate insular margins, and thus create a remarkable setting in which to compare demersal fish communities across various features. Concurrently, several water masses are vertically layered in the water column, creating strong stratification layers corresponding to specific abiotic conditions. In this study, we examined differences among fish assemblages across different features (e.g., seamount, canyon, bank/ridge) and water masses at depths ranging from 98 to 4060 m in the northeastern Caribbean. We conducted 26 remotely operated vehicle dives across 18 sites, identifying 156 species of which 42% of had not been previously recorded from particular depths or localities in the region. While rarefaction curves indicated fewer species at seamounts than at other features in the NE Caribbean, assemblage structure was similar among the different types of features. Thus, similar to seamount studies in other regions, seamounts in the Anegada Passage do not harbor distinct communities from other types of rugged features. Species assemblages, however, differed among depths, with zonation generally corresponding to water mass boundaries in the region. High species turnover occurred at depths <1200 m, and may be driven by changes in water mass characteristics including temperature (4.8–24.4 °C) and dissolved oxygen (2.2–9.5 mg per l). Our study suggests the importance of water masses in influencing community structure of benthic fauna, while considerably adding to the knowledge of mesophotic and deep-sea fish biogeography. [ABSTRACT FROM AUTHOR]

A complete understanding of how parasites influence marine ecosystem functioning requires characterizing a broad range of parasite-host interactions while determining the effects of parasitism in a variety of habitats. In deep-sea fishes, the prevalence of parasitism remains poorly understood. Knowledge of ectoparasitism, in particular, is limited because collection methods often cause dislodgment of ectoparasites from their hosts. High-definition video collected during 43 remotely operated vehicle surveys (2013–2014) provided the opportunity to examine ectoparasitism on fishes across habitats (open slope, canyon, seamount, cold seep) and depths (494–4689 m) off the northeastern U.S., while providing high-resolution images and valuable observations of fish behavior. Only 9% (n = 125 individuals) of all observed fishes (25 species) were confirmed with ectoparasites, but higher percentages (∼33%) were observed for some of the most abundant fish species (e.g., Antimora rostrata) . Ectoparasites included two copepod families (Lernaeopodidae, Sphyriidae) that infected four host species, two isopod families (Cymothoidae, Aegidae) that infected three host species, and one isopod family (Gnathiidae) that infected 19 host species. Hyperparasitism was also observed. As host diversity declined with depth, ectoparasite diversity declined; only gnathiids were observed at depths down to 3260 m. Thus, gnathiids appear to be the most successful group to infect a diversity of fishes across a broad depth range in the deep sea. For three dominant fishes ( A. rostrata , Nezumia bairdii , Synaphobranchus spp.), the abundance and intensity of ectoparasitism peaked in different depths and habitats depending on the host species examined. Notably, gnathiid infections were most intense on A. rostrata , particularly in submarine canyons, suggesting that these habitats may increase ectoparasite infections. Although ectoparasitism is often overlooked in deep-sea benthic communities, our results demonstrate that it occurs widely across a variety of habitats, depths, and locations and is a significant component of deep-sea biodiversity. [ABSTRACT FROM AUTHOR]

Deep-sea corals are the structural foundation of their ecosystems along continental margins worldwide, yet the factors driving their broad distribution are poorly understood. Environmental factors, especially depth-related variables including water mass properties, are thought to considerably affect the realized distribution of deep-sea corals. These factors are governed by local and regional oceanographic conditions that directly influence the dispersal of larvae, and therefore affect the ultimate distribution of adult corals. We used molecular barcoding of mitochondrial and nuclear sequences to identify species of octocorals in the genus Paramuricea collected from the Labrador Sea to the Grand Banks of Newfoundland, Canada at depths of 150–1500 m. The results of this study revealed overlapping bathymetric distributions of the Paramuricea species present off the eastern Canadian coast, including the presence of a few cryptic species previously designated as Paramuricea placomus . The distribution of Paramuricea species in the western North Atlantic differs from the Gulf of Mexico, where five Paramuricea species exhibit strong segregation by depth. The different patterns of Paramuricea species in these contrasting biogeographic regions provide insight into how water mass structure may shape species distribution. Investigating Paramuricea prevalence and distribution in conjunction with oceanographic conditions can help demonstrate the factors that generate and maintain deep-sea biodiversity. [ABSTRACT FROM AUTHOR]

The J-wave pattern on 12-lead ECG is traditionally defined as a positive deflection at junction between the end of the QRS and the beginning of the ST-segment. This pattern has recently been associated with increased risk for idiopathic ventricular fibrillation in the absence of cardiovascular disease. The interest for the clinical significance of J-wave pattern as a potential ECG hallmark of high risk for cardiac arrest has recently been reinforced by the growing practice of ECG screening, such as occurs in large population of young competitive athletes. The available scientific evidence shows that the J-wave pattern is relatively common in trained athletes (ranging from 14% to 44%) and, differently from subjects who suffered from ventricular fibrillation, commonly localized in lateral leads while it is relatively rare to be found in inferior leads. Furthermore the J-wave pattern has been demonstrated to be a dynamic phenomenon related to the training status, with the larger prominence at the peak of training and with an inverse relation between magnitude of J-wave and heart rate. In addition the J-wave pattern is usually associated with other ECG changes, such as increased QRS voltages and ST-segment elevation, as well as LV remodeling, suggesting that it likely represents another expression of the physiologic athlete's heart. Finally the scientific data available demonstrated that during a medium follow-up period the J-wave pattern does not convey risk for adverse cardiac events, including sudden death or ventricular tachyarrhythmias. [ABSTRACT FROM AUTHOR]

Background J wave/QRS slurring (early repolarization) on 12-lead ECG has been associated with increased risk for ventricular fibrillation in the absence of cardiovascular (CV) disease. Objective The purpose of this study was to assess the prevalence and clinical significance of J wave/QRS slurring in a large population of competitive athletes. Methods Seven hundred four athletes (436 males [62%], age 25 ± 5 years) free of CV disease who had engaged in 30 different sports were examined. Serial clinical, ECG, and echocardiographic evaluations were available over 1 to 18 years of follow-up (mean 6 ± 4 years). Results J wave was found in 102 athletes (14%) and was associated with QRS slurring in 32 (4%). It was found most commonly in anterior, lateral, and inferior leads (n = 73 [72%]), occasionally in lateral leads (n = 26 [25%]), and rarely in inferior leads (n = 3 [3%]). Most of 102 athletes (n = 86 [84%]) also showed ST-segment elevation. J wave/QRS slurring was associated with other training-related ECG changes (ie, increased R/S-wave voltages in 76%) and left ventricular (LV) morphologic remodeling (LV mass 199 ± 48 g vs 188 ± 56 g, P <.05). During follow-up, no athlete with J wave experienced cardiac event or ventricular tachyarrhythmias, or developed structural CV disease. Conclusion In athletes, early repolarization pattern usually is associated with other ECG changes, such as increased QRS voltages and ST-segment elevation, as well as LV remodeling, suggesting that it likely represents another benign expression of the physiologic athlete’s heart. J wave (early repolarization) is common in highly trained athletes and does not convey risk for adverse cardiac events, including sudden death or tachyarrhythmias. [ABSTRACT FROM AUTHOR]

Deep-sea communities are becoming increasingly vulnerable to anthropogenic disturbances, as fishing, hydrocarbon exploration and extraction, and mining activities extend into deeper water. Negative impacts from such activities were recently documented in the Gulf of Mexico (GoM), where the Deepwater Horizon oil spill caused substantial damage to a deep-water octocoral community. Although a faunal checklist and numerous museum records are currently available for the entire GoM, local-scale diversity and assemblage structure of octocoral communities remains unknown, particularly in deep water. On a series of recent cruises (2008–2011) using remotely operated vehicles, 435 octocorals were collected from 33 deep-water sites (250–2500 m) in the northern GoM. To elucidate species boundaries, the extended mitochondrial barcode (COI+igr1+msh) was successfully amplified and sequenced for 422 of these specimens, yielding a total of 64 haplotypes representing at least 52 species. Further, at least 29% of the species collected were either previously not known to occur in the GoM (12 species) or represent new species (at least three species). Overall, species richness at each site was fairly low (1–12 spp.). The greatest species richness occurred at the shallowest (<325 m: GC140, n=8 spp.) and the deepest (2100–2500 m: DC673, n=12 spp., DC583, n=10 spp.) sites, and minimum taxonomic and phylogenetic (Faith's Index) diversity was evident at 600–950 m. This pattern is the opposite of the typical pattern of deep-sea diversity in the GoM, which normally peaks at mid-slope depths. Sorensen's Index of taxonomic β-diversity indicated that six distinct (65–95% dissimilarity) species assemblages corresponded with five depth breaks at ~325, 425, 600, 1100, and 2100 m. Further assemblage structure was observed within certain depth zones. Of note, within the 425–600 m depth range, species assemblages at the West Florida Slope differed from the other sites, corresponding to an established biogeographic barrier. The phylogenetic approach used in this study provided important insights into the species boundaries of many taxa while demonstrating that evolutionary history plays a critical role in community structure of deep-sea octocorals. [ABSTRACT FROM AUTHOR]

Species in the genus Paramuricea are among the most common corals in deep waters (>200 m) of the Gulf of Mexico. Paramuricea spp. increase habitat heterogeneity and provide substrate for numerous faunal associates, including ophiuroids that occur on the majority of coral colonies. In light of the Deepwater Horizon oil spill in the Gulf of Mexico, it has become apparent that there is a critical need for data on population dynamics within this genus. To date, at least one species of Paramuricea (P. biscaya) is known to be negatively impacted by the spill. Using remotely operated vehicles from 2009 to 2011, we documented the density and size frequency distributions of Paramuricea across 21 sites at depths of 250–2500 m. Molecular barcoding (mtCOI+igr+MutS) was used to delineate species boundaries among the specimens collected. Results suggested that seven haplotypes are present in the Gulf, and appear to be partially segregated by depth [(type H: <260 m) (type E: 278–445 m) (type A: 443–541 m) (types B1–B3: 800–2600 m)]. Densities of Paramuricea spp. determined by ROV surveys were mapped onto high-resolution bathymetric data, which confirmed the corals' preference for topographic highs composed of hard substrata. At any one site, densities ranged from 0.043±0.01 (VK906, 380 m) to 1.18±0.81 colonies/m2 (GC852, 1410 m). Mortality and recruitment rates were estimated from size-frequency data combined with estimated growth rates. Mortality rate decreased with size, from approximately 20% and 70% in new recruits of Paramuricea B3 and P. biscaya respectively, to less than 10% in colonies over 40 cm in both species. Recruitment rates were estimated from less than one to over 30 individuals per year per site, but patterns in size-frequency histograms suggest that this process is highly variable at the different sites and at different times. These data illustrate that populations of the slow-growing Paramuricea species are sparsely distributed and exhibit low recruitment rates, making them highly susceptible to anthropogenic threats. [ABSTRACT FROM AUTHOR]

Abstract: Remodeling of the aortic root may be expected to occur in athletes as a consequence of hemodynamic overload associated with exercise training; however, there are few data reporting its presence or extent. This review reports the current knowledge regarding the prevalence, upper limits, and clinical significance of aortic remodeling induced by athletic training. Several determinants impact aortic dimension in healthy, nonathletic individuals, including height, body size, age, sex, and blood pressure. Of these factors, anthropometric variables have the greatest impact. In athletes, the effect of exercise training appears to have only a modest additional influence on aortic dimension, although previous studies have produced some conflicting results. Specifically, data derived from the largest available athletic cohort suggest that the most hemodynamically intense endurance disciplines (eg, cycling and swimming) are associated with a significant but mild increase in aortic dimensions. Power disciplines, instead, (eg, weight lifting, throwing events) have only trivial, if any, impact. In contrast, selected data from a different athlete population suggest a more significant dimensional aortic remodeling in strength-trained individuals. In our experience, the 99th percentile value of aortic root diameter corresponds to 40 mm in males and 34 mm in females, which can reasonably be considered the upper limits of physiologic aortic root remodeling. However, a small proportion of apparently healthy male athletes (approximately 1%) show aortic enlargement above the upper limits, in the absence of systemic disease (ie, Marfan syndrome). Athletes presenting with aortic enlargement may demonstrate a further dimensional increase in midlife leading to clinically relevant aortic dilatation. Occasionally, dilation may be severe enough to warrant consideration for surgical treatment. Therefore, serial clinical and echocardiographic evaluations are recommended in athletes when aortic root exceeds the sex-specific thresholds. [Copyright &y& Elsevier]

Abstract: Midwater fish faunas over three cold seep habitats >1000m (AC601, GC852, AT340) and over a cold-water coral bank (VK826, <1000m) in the north-central Gulf of Mexico (GOM) are described and compared. Day and night discrete-depth sampling was accomplished at each study site, 9–29 August 2007, using an opening–closing Tucker trawl towed at depth for 30min. The 159 Tucker trawl stations yielded 9802 individuals and at least 126 species (30 families) of juvenile and adult midwater fishes. Myctophidae (38 species, 28% of the total catch), Stomiidae (17 species, 1.4%), Gonostomatidae (12 species, 56%), Sternoptychidae (10 species, 6%), and Phosichthyidae (5 species, 6%) dominated catches at all sites. Thirty-one species (8 families) comprised about 90% of the overall abundance of fishes across the four sites. Despite the wide separation of study sites and some differences in physical oceanography, geographic and temporal patterns in mesopelagic fish assemblages were not evident (ANOSIM, Global R=0.20, p=0.1%, pairwise R values <0.3). However, station groupings were related mostly to similarities in sampled depths (SIMPROF, p<1.5%). Upper water-column station groups (<400m) were typified by Lepidophanes guentheri, Diaphus dumerilii, Vinciguerria nimbaria, Vinciguerria poweriae, Valenciennellus tripunctulatus, Argyropelecus aculeatus, Notolychnus valdiviae, Benthosema suborbitale, Gonostoma elongatum, and Hygophum taaningi. Deeper station groups (mean depth=609m) were typified by Cyclothone alba, Cyclothone acclinidens, Cyclothone braueri, Cyclothone obscura, Cyclothone pallida, Cyclothone pseudopallida, V. tripunctulatus, and Hygophum benoiti. Depth, diel, and size distributions were also analyzed for abundant species. For example, Cyclothone spp., abundant at all sites except VK826, usually occurred in deeper waters (>130m), especially during daylight hours (>335m). Most Cyclothone individuals were captured at night at GC852, whereas catches were more evenly distributed across times at AT340 and VK826. Cyclothone spp. individuals occurred in the deeper parts of the sampled depth range at AT340 and VK826 at all times compared with GC852, where they appeared to undergo a diel migration. The two most abundant Cyclothone spp., C. pallida and C. pseudopallida, had the broadest depth ranges (150–1377m) and exhibited a trend for larger specimens to occur deeper at GC852. Most V. tripunctulatus were captured at night and tended to have larger mean sizes in deeper waters. This species did not exhibit strong diel patterns of vertical distribution. Shallower depths were occupied at night by some individuals at all sites, but most individuals remained somewhat deeper at night at VK826 (350–450m at night and 200–350m by day) and AT340 (200–600m at night and 300–500m by day) compared with GC852 (150–450m at night and 750 and 1000m by day). Nearly all Vinciguerria poweriae were caught at night, and no clear trend of size with depth was apparent. This species occupied a wider depth range at night, with most in the upper 200m. Most myctophids, the strongest diel migrators, were captured at night at the offshore stations. The dominant myctophid, N. valdiviae, was most abundant at GC852 (550–1050m by day and 50–750m at night), but diel movement was more distinct at AT340 (<200m at night and 350–500m by day). No size-related trends with depth were apparent at any site for N. valdiviae, and size distributions were similar among sites. This study and others support the hypothesis that there is a geographically similar mesopelagic fish fauna throughout the GOM. However, the fauna does vary by depth, with some species remaining in deep waters at all times (e.g., Cyclothone spp.) and others occurring at mid-depths and exhibiting varying degrees of diel migration (e.g., many myctophids). Even though faunal composition is similar across the GOM, some species exhibit different movement behaviors at different locations. Such variances could be related to differences in physical or chemical factors, food resources, lunar phase, or bottom depth. [Copyright &y& Elsevier]

Numerous submarine canyons along the United States middle Atlantic continental margin support enhanced productivity, diverse and unique habitats, active fisheries, and are vulnerable to various anthropogenic disturbances. During two cruises (15 Aug–2 Oct 2012 and 30 Apr–27 May 2013), Baltimore and Norfolk canyons and nearby areas (including two cold seeps) were intensively surveyed to determine demersal fish distributions and habitat associations. Overall, 34 ROV dives (234–1612 m) resulted in 295 h of bottom video observations and numerous collections. These data were supplemented by 40, 30-min bottom trawl samples. Fish observations were assigned to five general habitat designations: 1) sand-mud (flat), 2) sloping sand-mud with burrows, 3) low profile gravel, rock, boulder, 4) high profile, canyon walls, rocks or ridges, and 5) seep-mixed hard and soft substrata, the later subdivided into seven habitats based on amounts of dead mussel and rock cover. The influence of corals, sponges and live mussels (seeps only) on fish distributions was also investigated. Both canyon areas supported abundant and diverse fish communities and exhibited a wide range of habitats, including extensive areas of deep-sea corals and sponges and two nearby methane seeps (380–430 m, 1455–1610 m). All methods combined yielded a total of 123 species of fishes, 12 of which are either new records for this region or have new range data. Depth was a major factor that separated the fish faunas into two zones with a boundary around 1400 m. Fishes defining the deeper zone included Lycodes sp., Dicrolene introniger, Gaidropsaurus ensis, Hydrolagus affinis, Antimora rostrata , and Aldrovandia sp. Fishes in the deep zone did not exhibit strong habitat affinities, despite the presence of a quite rugged, extensive methane seep. We propose that habitat specificity decreases with increasing depth. Fishes in the shallower zone, characterized by Laemonema sp., Phycis chesteri, Nezumia bairdii, Brosme brosme , and Helicolenus dactylopterus , exhibited a variety of habitat use patterns. In general, fish assemblages in the soft substrata areas (dominated by P. chesteri, N. bairdii, Glyptocephalus cynoglossus, Lophius americanus, Merluccius albidus ) were different from those in more complex habitats (dominated by Laemonema spp., Hoplostethus spp., B. brosme , Benthocometes robustus, L. americanus, Dysommina rugosa ). Although, when present, the dense coral and sponge cover did not statistically affect general fish assemblage patterns in hard bottom habitats, these sessile organisms markedly increased habitat complexity, and some fish species exhibited close association with them. Fish species compositions in the two canyons were not substantially different from the surrounding slopes. However, the diversity of habitats within both the canyons and seeps exerted an important influence on assemblage structure. At least for some species (e.g., B. brosme ) canyon and seep environments may be a refuge from intensive bottom fishing activities. We frequently observed evidence of commercial and recreational fishing activity (lost gear on bottom and fishing boats in the area) throughout the canyons and some resulting habitat damage. Conservation measures for the unique and more vulnerable areas (seep and coral habitats) have recently been approved. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess, using 3-dimensioanl echocardiography, the morphologic characteristics, determinants, and physiologic limits of left ventricular (LV) remodeling in 511 Olympic athletes (categorized in skill, power, mixed, and endurance sport disciplines) and 159 sedentary controls matched for age and gender. All subjects underwent 3-dimensional echocardiography for the assessment of LV volumes, ejection fraction, mass, remodeling index (LV mass/LV end-diastolic volume), and systolic dyssynchrony index (obtained by the dispersion of the time to minimum systolic volume in 16 segments). Athletes had higher LV end-diastolic volumes (157 ± 35 vs 111 ± 26 ml, p <0.001) and mass (156 ± 38 vs 111 ± 25 g, p <0.001) compared to controls. Body surface area and age had significant associations with LV end-diastolic volume (R2 = 0.49, p <0.001) and mass (R2 = 0.51, p <0.001). Covariance analysis showed that also gender and type of sport were significant determinants of LV remodeling; in particular, the highest impact on LV end-diastolic volume and mass was associated with male gender and endurance disciplines (p <0.001). Regardless of the type of sport, athletes had similar LV remodeling indexes to controls (1.00 ± 0.06 vs 1.01 ± 0.07 g/mL, p = 0.410). No differences were found between athletes and controls for the ejection fraction (62 ± 5% and 62 ± 5%, p = 0.746) and systolic dyssynchrony index (1.06 ± 0.40% and 1.37 ± 0.41%, p = 0.058). In conclusion, 3-dimensional echocardiographic morphologic and functional assessment of the left ventricle in Olympic athletes demonstrated a balanced adaptation of LV volume and mass, with preserved systolic function, regardless of specific disciplines participated. [ABSTRACT FROM AUTHOR]

Abstract: The Lophelia pertusa community at Viosca Knoll (VK826) is the most extensive found to date in the Gulf of Mexico. As part of a multi-disciplinary study, the physical setting of this area was described using benthic landers, CTD transects and remotely operated vehicle observations. The site was broadly characterised into three main habitats: (1) dense coral cover that resembles biogenic reef complexes, (2) areas of sediment, and (3) authigenic carbonate blocks with sparse coral and chemosynthetic communities. The coral communities were dominated by L. pertusa but also contained numerous solitary coral species. Over areas that contained L. pertusa, the environmental conditions recorded were similar to those associated with communities in the north-eastern Atlantic, with temperature (8.5–10.6°C) and salinity (∼35) falling within the known species niche for L. pertusa. However, dissolved oxygen concentrations (2.7–2.8mll−1) and density (σΘ , 27.1–27.2kgm−3) were lower and mass fluxes from sediment trap data appeared much higher (4002–4192mgm−2 d−1). Yet, this species still appears to thrive in this region, suggesting that L. pertusa may not be as limited by lower dissolved oxygen concentrations as previously thought. The VK826 site experienced sustained eastward water flow of 10–30cms−1 over the 5-day measurement period but was also subjected to significant short-term variability in current velocity and direction. In addition, two processes were observed that caused variability in salinity and temperature; the first was consistent with internal waves that caused temperature variations of 0.8°C over 5–11h periods. The second was high-frequency variability (20–30min periods) in temperature recorded only at the ALBEX site. A further pattern observed over the coral habitat was the presence of a 24h diel vertical migration of zooplankton that may form part of a food chain that eventually reaches the corals. The majority of detailed studies concerning local environmental conditions in L. pertusa habitats have been conducted within the north-eastern Atlantic, limiting most knowledge of the niche of this species to a single part of an ocean basin. Data presented here show that the corals at VK826 are subjected to similar conditions in temperature, salinity, and flow velocity as their counterparts in the north-east Atlantic, although values for dissolved oxygen and density (sigma-theta: σΘ ) are different. Our data also highlight novel observations of short-term environmental variability in cold-water coral habitat. [Copyright &y& Elsevier]

Objectives: In the present study we assessed the distribution and clinical significance of left atrial (LA) size in the context of athlete''s heart and the differential diagnosis from structural heart disease, as well as the proclivity to supraventricular arrhythmias. Background: The prevalence, clinical significance, and long-term arrhythmic consequences of LA enlargement in competitive athletes are unresolved. Methods: We assessed LA dimension and the prevalence of supraventricular tachyarrhythmias in 1,777 competitive athletes (71% of whom were males), free of structural cardiovascular disease, that were participating in 38 different sports. Results: The LA dimension was 23 to 50 mm (mean, 37 ± 4 mm) in men and 20 to 46 mm (mean, 32 ± 4 mm) in women and was enlarged (i.e., transverse dimension ≥40 mm) in 347 athletes (20%), including 38 (2%) with marked dilation (≥45 mm). Of the 1,777 athletes, only 14 (0.8%) had documented, symptomatic episodes of either paroxysmal atrial fibrillation (n = 5; 0.3%) or supraventricular tachycardia (n = 9; 0.5%), which together occurred in a similar proportion in athletes with (0.9%) or without (0.8%; p = NS) LA enlargement. Multivariate regression analysis showed LA enlargement in athletes was largely explained by left ventricular cavity enlargement (R2 = 0.53) and participation in dynamic sports (such as cycling, rowing/canoeing) but minimally by body size. Conclusions: In a large population of highly trained athletes, enlarged LA dimension ≥40 mm was relatively common (20%), with the upper limits of 45 mm in women and 50 mm in men distinguishing physiologic cardiac remodeling (“athlete''s heart”) from pathologic cardiac conditions. Atrial fibrillation and other supraventricular tachyarrhythmias proved to be uncommon (prevalence &#60;1%) and similar to that in the general population, despite the frequency of LA enlargement. Left atrial remodeling in competitive athletes may be regarded as a physiologic adaptation to exercise conditioning, largely without adverse clinical consequences. [Copyright &y& Elsevier]

Deepwater corals are found on hard grounds of the continental shelf and slope of all ocean basins, where they enhance the abundance and biodiversity of invertebrates and fishes. Despite their essential role in deep-sea ecosystems, the knowledge of the factors that promote or impede connectivity among discrete coral communities remains elusive. Logistical challenges prevent a direct quantification of the essential factors affecting connectivity, such as timing of spawning, time spent in the water column, and settlement behavior, as well as the details of the physical environment and its variability. This study argues that an integrated framework including population genetic approaches and physical models of the ocean circulation with larval particle tracking capabilities can enhance our understanding. Genetic approaches allow determination of general time-integrated patterns of dispersal distance and direction in virtually any species, while transport models can refine understanding of the processes behind the observed dispersal patterns. Here, this integrated approach is applied towards investigating the connectivity of a deepwater coral, Callogorgia delta , along the upper continental slope of the northern Gulf of Mexico. The circulation in the basin is simulated by a regional ocean model at 1 km horizontal resolution, which is sufficiently detailed to allow for the generation and evolution of submesoscale eddies and vorticity filaments, and for a reliable representation of major bathymetric features. Building upon data from four sites spanning about 250 km of distance and 400 m of depth, it is concluded that depth differences on scales of tens to at most few hundreds of meters are sufficient to limit C. delta connectivity among sites. This result has important implications in the development of restoration and preservation strategies of deepwater corals in the Gulf of Mexico and calls for carefully accounting for the depth dimension in these efforts. • Deepwater coral connectivity is logistically hard to quantify. • Genetic approaches help determining time-integrated patterns of dispersal distance/direction. • Transport models can refine understanding of the processes behind observed patterns. • An integrated framework (population genetic + modeling) enhances understanding. • In the Gulf of Mexico deepwater coral, C. Delta , shows depth separation due to limited transport. [ABSTRACT FROM AUTHOR]