Monitoring Macroalgae in the Great Bay Estuary for 2014

Four more intertidal fixed transect sites were added to the long5term macroalgal monitoring array, resulting in a total of eight sites for the Great Bay Estuary. Monitoring results from 2014 show high levels of cover of nuisance green and red algae (Ulva and Gracilaria, respectively) at all sites except near the mouth of the Estuary. Seasonal sampling of algal cover confirmed earlier work that showed mid5summer accumulations of green algae (primarily Ulva)lactuca) were largely replaced in late summer and fall by red algae (two species of Graciliaria, one native and the other introduced). A determination of whether intertidal macroalgal populations are increasing over time will require a longer time series and would likely benefit from historical analysis of earlier collections of intertidal macroalgae. To this end, a method for analysis of historical photographs was developed

Macroalgal Monitoring in the Great Bay Estuary: 2018 Annual Report

Since 2013, the abundance and taxa of intertidal macroalgae have been assessed at fixed locations throughout the Great Bay Estuary in New Hampshire. Algal abundance may be influenced by environmental conditions such as nutrient levels, water temperature, light and invasive species. Therefore, abundance of different algal groups can provide insights into the overall health of the estuary and signal ecological change. In 2018, intertidal abundance data for percentage cover and biomass were collected, as planned, from five of the eight sites. For the first time, subtidal sampling arrays were also incorporated at all four sites in Great Bay proper to monitor macroalgae at lower elevations and to collect data on eelgrass communities coexisting with the algae

Seaweed Monitoring in the Great Bay Estuary: 2019 Annual Report

As global warming increases temperature and nitrogen inputs change—either due to greater inputs associated with growing populations in the Great Bay or with nitrogen reductions at wastewater treatment plants—it is important to understand how these changes are impacting the estuary. To that end, the abundance and taxa of intertidal seaweeds have been assessed at fixed locations throughout the estuary since 2013. Seaweed abundance may be influenced by environmental conditions such as nutrient levels, water temperature, light availability, and invasive species. Therefore, seaweed communities can provide insights into the overall health of the estuary and signal ecological change. In 2019, abundance data (percent cover and biomass) were collected from five of the eight intertidal sampling locations and four subtidal locations. Data from 2013-2019 show appreciable cover and biomass of nuisance seaweeds (reds and greens), including several introduced species. Green seaweeds decreased in cover at the two intertidal sites that are sampled annually (Depot Road and Adams Point), and cover of red seaweed decreased at one site (Depot Road)

A preliminary checklist of the marine algae of Campobello Island, New Brunswick, Canada

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Monitoring Macroalgae in the Great Bay Estuary for 2016

In 2016, five of the eight locations with fixed intertidal transects were sampled as part of a long-term effort to monitor changes in the abundance of macroalgae in the Great Bay Estuary. Since 2013, the abundance and taxa of intertidal macroalgae have been assessed at fixed locations to serve as an indicator of ecological changes in the Estuary. Changes in the algae may reflect changes associated with excess nutrient loading, termed eutrophication, and may be especially informative of algal impacts to eelgrass meadows in the Estuary. Macroalgae collections over the past four years have resulted in the accumulation of two years of data for six locations, three years of data for a seventh location and four years of data for an eighth location. Based upon this short-term data set we found significant cover and biomass of nuisance algae, some of these are recognized as introduced, invasive species. Monitoring results from 2016 show high levels of cover of nuisance algae, either green or red (Ulva and Gracilaria, respectively) at all sites sampled, but especially at the lowest elevations, nearest to the subtidal habitats. Visual examination of our intertidal transect data along with anecdotal observations suggest that algal populations are changing, but long-term collections will be needed to determine whether significant differences in intertidal macroalgal populations are occurring over time

Seaweed Monitoring in the Great Bay Estuary: 2019 Annual Report

As global warming increases temperature and nitrogen inputs change—either due to greater inputs associated with growing populations in the Great Bay or with nitrogen reductions at wastewater treatment plants—it is important to understand how these changes are impacting the estuary. To that end, the abundance and taxa of intertidal seaweeds have been assessed at fixed locations throughout the estuary since 2013. Seaweed abundance may be influenced by environmental conditions such as nutrient levels, water temperature, light availability, and invasive species. Therefore, seaweed communities can provide insights into the overall health of the estuary and signal ecological change. In 2019, abundance data (percent cover and biomass) were collected from five of the eight intertidal sampling locations and four subtidal locations. Two more sampling arrays were established at each subtidal site, making three replicates per site. Data from 2013-2019 show appreciable cover and biomass of nuisance seaweeds (reds and greens), including several introduced species. Green seaweeds decreased in cover at the two intertidal sites that are sampled annually (Depot Road and Adams Point), and cover of red seaweed decreased at one site (Depot Road). However, there were no decreases at the other six sites, and results from 2019 still show high levels of nuisance seaweed at the lowest intertidal elevations. In subtidal areas, percent cover assessments by snorkel appeared successful based on strong correlations between cover and biomass. Percent cover of seagrass measured by snorkel was very similar to independent measurements from underwater photos. The abundance of seaweed in association with eelgrass beds was ecologically significant and may have impacted eelgrass density and productivity. Further monitoring of seaweed and eelgrass is required to determine potential impacts to the estuary from emerging threats of increased nutrients from impervious surfaces and rising water temperatures due to global warming, as well as reduced nutrient threats from improvements to wastewater treatment plants and stormwater management. For example, the 2019 eelgrass survey showed an increase in area of eelgrass beds within Great and Little Bays which co-occurred with declines in nuisance seaweed at two of our stations in Great Bay

Participation in voluntary and community organisations in the United Kingdom and the influences on the self-management of long-term conditions

Voluntary and community organisations (VCOs) have health benefits for those who attend and are viewed as having the potential to support long-term condition management. However, existing community-level understandings of participation do not explain the involvement with VCOs at an individual level, or the nature of support, which may elicit health benefits. Framing active participation as ‘doing and experiencing’, the aim of this qualitative study was to explore why people with long-term vascular conditions join VCOs, maintain their membership and what prevents participation. Twenty participants, self-diagnosed as having diabetes, chronic heart disease or chronic kidney disease, were purposefully sampled and recruited from a range of VCOs in the North West of England identified from a mapping of local organisations. In semi-structured interviews, we explored the nature of their participation. Analysis was thematic and iterative involving a continual reflection on the data. People gave various reasons for joining groups. These included health and well-being, the need for social contact and pursuing a particular hobby. Barriers to participation included temporal and spatial barriers and those associated with group dynamics. Members maintained their membership on the basis of an identity and sense of belonging to the group, developing close relationships within it and the availability of support and trust. Participants joined community groups often in response to a health-related event. Our findings demonstrate the ways in which the social contact associated with continued participation in VCOs is seen as helping with long-term condition management. Interventions designed at improving chronic illness management might usefully consider the role of VCOs

Ultrasonic assisted creep feed grinding of Inconel 718

AbstractThe paper details the effects of depth of cut and vibration amplitude when ultrasonic assisted (US) creep feed grinding Inconel 718 with an open structured alumina based wheel. The workpiece was actuated at a constant frequency (∼20.5kHz) via a block sonotrode attached to a 1kW piezoelectric transducer-generator system. A full factorial experimental array comprising 12 tests was conducted involving variation in depth of cut (0.1, 0.5 and 1.0mm), amplitude of vibration (high and low) and grinding condition (with and without vibration). Wheel speed and table feed were fixed at 30m/s and 600mm/min respectively for all tests. Application of ultrasonic vibration resulted in reductions in vertical (Fv) and horizontal (Fh) force components by up to 28% and 37% respectively, however greater wheel wear (30-60% lower G-ratio) occurred under hybrid operation due to increased grit/bond fracture. SEM micrographs of the slots machined with US assistance revealed higher levels of side flow/ploughing in comparison to standard creep feed ground specimens. Additionally, more overlapping grit marks were visible on surfaces subject to ultrasonic assisted grinding. Increasing amplitude of vibration produced lower grinding forces (up to 30% for Fv and 43% for Fh) but higher workpiece surface roughness (up to 24%). Topographic maps of grinding wheel surface replicas indicated that use of US vibration generally led to an increase in the number of active cutting points on the wheel

Position Reconstruction in Drift Chambers operated with Xe, CO2 (15%)

We present measurements of position and angular resolution of drift chambers operated with a Xe,CO$_2$(15%) mixture. The results are compared to Monte Carlo simulations and important systematic effects, in particular the dispersive nature of the absorption of transition radiation and non-linearities, are discussed. The measurements were carried out with prototype drift chambers of the ALICE Transition Radiation Detector, but our findings can be generalized to other drift chambers with similar geometry, where the electron drift is perpendicular to the wire planes.Comment: 30 pages, 18 figure