Cruise Report C-109 : scientific activities undertaken aboard SSV Corwith Cramer, St. Thomas - Carriacou - Grenada - Roatan - Cozumel - Miami, 30 November 1989 - 10 January 1990

St. Thomas - Carriacou - Grenada - Roatan - Cozumel - Miami, FL, 30 November 1989 - 10 January 1990This cruise report is a partial record of the formal education and scientific activities conducted during the sea component with SEA Class 109 on the SSV Corwith Cramer. The emphasis is on the formally scheduled activities, the scientific sampling, the laboratory analyses and student research projects. For those who experienced C-109 it is of course an incomplete reflection of all that transpired and all that was learned. An accurate characterization of C-109 would have to clarify in detail the intensity and diversity of the educational experiences

Late-holocene channel meander migration and mudflat accumulation rates, Lagoon of Venice, Italy

Coring in the Lagoon of Venice mudflats along previously collected high-resolution subbottom seismic-reflection survey profile lines has enabled the collection of interlayered radiocarbon-datable terrestrial plant material. Along present and former meander bends, dipping laminated sandy channel-bank deposits rest in sharp lithostratigraphic and chronologic contrast to the adjacent and overlying mudflat deposits. Horizontal channel migration rates of roughly 10 to 20 meters per century are orders of magnitude faster than the minimum estimates of vertical mudflat silt accumulation, which range from 5 to 25 centimeters per century. Given the nearly 6000-year history since the late-Holocene marine transgression that produced the initial lagoon environments of deposition, it is no surprise that channel meander migration has left a prevalence of channel-bank deposits in the subsurface lithostratigraphy. Furthermore, regional subsidence and rising relative sea level continue to enhance the net accumulation of mudflat and salt marsh deposition on top of the older deposits. Tapered variations of tidal-channel width, depth, and flow velocity, as well as wind-driven waves with associated intensities of turbulence along the meandering paths, lead to recognizable sediment grain size trends and lagoon deposit stratigraphy. Human interventions, such as dredging, spoil disposal, and powerboat wakes, introduce other contrasting processes and depositional features. For complete understanding of the depositional environments in the lagoon, the full set of dynamic processes and depositional consequences often need to be considered. Patterns and processes revealed in this case study probably have broad applicability to other coastal lagoon environments experiencing significant tidal flow and sea-level change

Magnetic stratigraphy and sedimentology of Holocene glacial marine deposits in the Palmer Deep, Bellingshausen Sea, Antarctica: implications for climate change? Marine Geology 152

Abstract The Palmer Deep is a closed bathymetric depression on the Antarctic Peninsula continental shelf. It contains three separate sub-basins. These basins lie along a northeast-southwest axis with water depths ranging from >1400 m to the southwest (Basins II and III) to just over 1000 m to the northeast (Basin I). Six sediment piston cores were collected from the study region; these cores clearly demonstrate the varied sediment character for each basin. Sediments in Basin I are laminated and thinly bedded consisting of diatomaceous, pelagic=hemipelagic sediments, siliciclastic, terrigenous sediments, and ice rafted, hemipelagic sediments. In concurrence with other investigators, we propose that these laminations and thin beds represent climatically forced productivity cycles. Basin II and Basin III sediments alternate between pelagic=hemipelagic units and bio-siliceous mud turbidites. Correlations between cores are based on their remarkable magnetic susceptibility (MS) records which indicate alternating biogenic (low MS) and siliciclastic (high MS) dominated sedimentation; the bio-siliceous mud turbidites are characterized by intermediate to low MS values. Cores taken from within the main axis of the basins are expanded ultra-high resolution sections. A core collected on the sill between Basins II and III represents a condensed sediment section and may contain a complete Holocene record of changing paleoenvironments, one that records the transition from a glacial, ice shelf environment to an open marine, Holocene environment. A sharp drop in magnetic susceptibility at mid-core is a common sedimentological feature of each basin. Presently, we favor a climate change hypothesis for this magnetic lithostratigraphic transition which may reflect the termination of the Holocene Hypsithermal and a marked change in productivity dated ca. 2500 years BP

Maternal corticotropin-releasing hormone is associated with LEP DNA methylation at birth and in childhood: an epigenome-wide study in Project Viva

BackgroundCorticotropin-releasing hormone (CRH) plays a central role in regulating the secretion of cortisol which controls a wide range of biological processes. Fetuses overexposed to cortisol have increased risks of disease in later life. DNA methylation may be the underlying association between prenatal cortisol exposure and health effects. We investigated associations between maternal CRH levels and epigenome-wide DNA methylation of cord blood in offsprings and evaluated whether these associations persisted into mid-childhood.MethodsWe investigated mother-child pairs enrolled in the prospective Project Viva pre-birth cohort. We measured DNA methylation in 257 umbilical cord blood samples using the HumanMethylation450 Bead Chip. We tested associations of maternal CRH concentration with cord blood cells DNA methylation, adjusting the model for maternal age at enrollment, education, maternal race/ethnicity, maternal smoking status, pre-pregnancy body mass index, parity, gestational age at delivery, child sex, and cell-type composition in cord blood. We further examined the persistence of associations between maternal CRH levels and DNA methylation in children's blood cells collected at mid-childhood (n = 239, age: 6.7-10.3 years) additionally adjusting for the children's age at blood drawn.ResultsMaternal CRH levels are associated with DNA methylation variability in cord blood cells at 96 individual CpG sites (False Discovery Rate <0.05). Among the 96 CpG sites, we identified 3 CpGs located near the LEP gene. Regional analyses confirmed the association between maternal CRH and DNA methylation near LEP. Moreover, higher maternal CRH levels were associated with higher blood-cell DNA methylation of the promoter region of LEP in mid-childhood (P < 0.05, β = 0.64, SE = 0.30).ConclusionIn our cohort, maternal CRH was associated with DNA methylation levels in newborns at multiple loci, notably in the LEP gene promoter. The association between maternal CRH and LEP DNA methylation levels persisted into mid-childhood

Prognostic value of pulmonary vein size in prediction of atrial fibrillation recurrence after pulmonary vein isolation: a cardiovascular magnetic resonance study

Background: The relationship between pulmonary vein (PV) anatomy and successful catheter ablation of atrial fibrillation (AF) is poorly understood Methods: First-pass contrast enhanced PV magnetic resonance angiography was performed in 71 consecutive patients prior to PV isolation. PV diameter and cross-sectional area (CSA) were measured prior to PV isolation. Any symptomatic or asymptomatic AF >10s was considered a recurrence. Early recurrence was defined as recurrent AF ≤30 days after PV isolation, while late recurrence of AF was defined as recurrent AF >30 days after. Results: At 1 year, 57 % had any recurrence of AF while 41 % had late recurrence of AF. Study subjects with one or more PV diameter in the top 10th percentile had trend toward more early recurrent AF (HR 1.99, p = 0.053). Study subjects with one or more PV CSA in the top 10th percentile had more late recurrent AF (HR 2.25, p = 0.039) and a trend toward more early recurrent AF (HR 1.94, p = 0.064). With multivariate analysis, PV size was not associated with early recurrent AF, but late recurrent AF was associated with one or more large PV, increased left atrial size, and non-paroxysmal AF. Study subjects with all three of these risk factors had a 100 % rate of late recurrent AF at 1 year, while those with none had a 7 % rate of late recurrent AF. Conclusions: Larger PV size is independently associated with more late recurrent AF after PV isolation. Determination of PV size prior to PV isolation may predict procedural success

Reasons and Means to Model Preferences as Incomplete

Literature involving preferences of artificial agents or human beings often assume their preferences can be represented using a complete transitive binary relation. Much has been written however on different models of preferences. We review some of the reasons that have been put forward to justify more complex modeling, and review some of the techniques that have been proposed to obtain models of such preferences

Comparison of Marine Spatial Planning Methods in Madagascar Demonstrates Value of Alternative Approaches

The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the “strict protection” class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during initial stages of the planning process. Choosing an appropriate approach ultimately depends on scientific and political factors including representation targets, likelihood of adoption, and persistence goals