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Production potential of seaweed and shellfish integrated aquaculture in Narragansett Bay (Rhode Island, U.S.) using an ecosystem model
No full textIntegrated aquaculture systems combining macroalgae with traditional fish and shellfish production represent an ecologically sound and economically attractive solution for farmers. To evaluate the potential of growing sugar kelp (Saccharina latissima) at existing oyster (Crassostrea virginica) farms in Narragansett Bay (NB; Rhode Island, U.S.), we developed an ecosystem model based on individual Dynamic Energy Budget models for kelp and oysters forced offline by a coupled 3D hydrodynamic-water quality model. Kelp growth during the cold winter months provides ecosystem services through the removal of nutrients in the bay as well as serving as an additional source of revenue for farmers. Locations with the most nutrient-rich waters at the northern end of the bay seem most suitable for kelp aquaculture, with oyster growth also reaching maxima at the same locations. Predictions of kelp biomass grown on lines ranged from 0.97 kgWW m–1 at the easternmost site at the Bay Entrance to 2.03 kgWW m–1 at the northernmost site in the Upper Bay, or 1.6 and 3.4 tons ha–1 on 6 m spaced line-farms, respectively. For denser production in 1.5 m spaced line-farms, estimates ranged between 6.5 and 13.5 tons ha–1. Depending on the different farm setups, we estimated the potential profits (based on delivered cost for consumer product) at 17,872 for a 1.5 m spaced line-farm. The N and C fixation of kelp ranged depending on spacing of longlines and time of harvest but reached maximum values of 1117 and 6184 kg ha−1, respectively. These estimates offer valuable information that should help producers and managers in their decision to direct efforts and investments into this developing activity in the U.S
Collaborative multiple change detection methods for monitoring the spatio-temporal dynamics of mangroves in Beibu Gulf, China
Get PDFMangrove ecosystems are one of the most diverse and productive marine ecosystems around the world, although losses of global mangrove area have been occurring over the past decades. Therefore, tracking spatio-temporal changes and assessing the current state are essential for mangroves conservation. To solve the issues of inaccurate detection results of single algorithms and those limited to historical change detection, this study proposes the detect–monitor–predict (DMP) framework of mangroves for detecting time-series historical changes, monitoring abrupt near-real-time events, and predicting future trends in Beibu Gulf, China, through the synergetic use of multiple detection change algorithms. This study further developed a method for extracting mangroves using multi-source inter-annual time-series spectral indices images, and evaluated the performance of twenty-one spectral indices for capturing expansion events of mangroves. Finally, this study reveals the spatio-temporal dynamics of mangroves in Beibu Gulf from 1986 to 2021. In this study, we found that our method could extract mangrove growth regions from 1986 to 2021, and achieved 0.887 overall accuracy, which proved that this method is able to rapidly extract large-scale mangroves without field-based samples. We confirmed that the normalized difference vegetation index and tasseled cap angle outperform other spectral indexes in capturing mangrove expansion changes, while enhanced vegetation index and soil-adjusted vegetation index capture the change events with a time delay. This study revealed that mangrove changes displayed historical changes in the hierarchical gradient from land to sea with an average annual expansion of 239.822 ha in the Beibu Gulf during 1986–2021, detected slight improvements and deteriorations of some contemporary mangroves, and predicted 72.778% of mangroves with good growth conditions in the future
Developing Motivational Interviewing Skills Among Undergraduate Nursing Students
No full textThe current study evaluated changes in undergraduate nursing students’ knowledge and self-efficacy in motivational interviewing. Fourth-year undergraduate nursing students completed a hybrid, online curriculum. Changes in knowledge and self-efficacy were assessed using a pretest/posttest design. Repeated measures analysis of variance was used to determine differences between knowledge and self-efficacy mean scores. Of the 144 students who participated in the study, 88.2% were female, 96.5% were non-Hispanic/Latino, 88.9% were White, and mean age was 21.3 years. There were significant increases in knowledge and self-efficacy mean scores between pre-survey and post-survey 1 and 2. There were no differences between post-surveys 1 and 2 scores. A hybrid, online curriculum using asynchronous modules and synchronous simulation training can facilitate nursing students’ learning experiences and enhance knowledge and self-efficacy about motivational interviewing
Associations of early life stress with leptin and ghrelin in healthy young adults
No full textBackground: Childhood adversity is a major risk factor for cardiometabolic health problems. Stress-related changes in diet suggest a role for endocrine factors that influence dietary intake, such as leptin and ghrelin. These hormones influence metabolism and may contribute to the relationship of early adversity, mental, and cardiometabolic health. This study examined levels of leptin and ghrelin in a sample of young adults with and without early life stress (ELS). Methods: Young adults ages 18–40 (N = 200; 68.5% female) were recruited from the community. Participants with ELS (N = 118) had childhood maltreatment, and a subset, n = 92 (78.0%) also had parental loss, and n = 65 (55.1%) also had a current psychiatric disorder. Control participants (N = 82) had no maltreatment, parental loss, or psychiatric disorders. Standardized interviews and self-reports assessed demographics, adversity, medical/psychiatric history, and health behaviors. Exclusion criteria included medical conditions and current medications other than hormonal contraceptives. Body Mass Index (BMI) and other anthropometrics were measured, and fasting plasma was assayed for total ghrelin and leptin with the Bio-Plex Pro Human Diabetes Panel. Results: While ELS was significantly associated with greater leptin (r = .16, p = .025), a finding which held when adjusted for age and sex (F(3196)= 28.32, p = .011), this relationship was abolished when accounting for BMI (p = .44). Participants with ELS also had significantly lower total ghrelin (r = .21, p = .004), which held adjusting for age and sex (p = .002) and was attenuated (p = .045) when the model included BMI (F=46.82, p \u3c .001). Current psychiatric disorder was also a significant predictor of greater leptin (r = .28, p \u3c .001) and lower ghrelin (r = .29, p = .003). In the model with ELS and covariates, psychiatric disorder remained significant (F=7.26, p = .008) and ELS was no longer significant (p = .87). Associations with severity and recent perceived stress were also examined. Conclusion: The relationship of ELS and leptin was no longer significant when accounting for BMI, suggesting potential avenues for intervention. Ghrelin findings persisted after correction for BMI, which may be secondary to physiological differences in the regulation of these hormones (leptin is produced by adipocytes, whereas ghrelin is produced primarily in the GI tract). Lastly, these findings suggest that psychiatric functioning may be a key component contributing to the relationship of lower total ghrelin and childhood adversity
Trace element composition of modern planktic foraminifera from an oxygen minimum zone: Potential proxies for an enigmatic environment
No full textOxygen limited marine environments, such as oxygen minimum zones, are of profound importance for global nutrient cycling and vertical habitat availability. While it is understood that the extent and intensity of oxygen minimum zones are responsive to climate, the limited suite of viable proxies for low oxygen pelagic environments continues to pose a real barrier for paleoclimate interpretations. Here we investigate the proxy potential of an array of trace element (Mg, Mn, Zn, and Sr) to Ca ratios from the shells of Globorotaloides hexagonus, a planktic foraminifer endemic to tropical through temperate oxygen minimum zones. A species-specific relationship between Mg/Ca and temperature is proposed for quantitative reconstruction of oxygen minimum zone paleotemperatures. Both Mn/Ca and Zn/Ca ratios vary with oxygen concentration and could be useful for reconstructing G. hexagonus habitat where the primary signal can be d\istinguished from diagenetic overprinting. Finally, a robust correlation between Sr/Ca ratios and dissolved oxygen demonstrates a role for Sr as an indicator of oxygen minimum zone intensity, potentially via foraminiferal growth rate. The analysis of these relatively conventional trace element ratios in the shells of an oxygen minimum zone species has tremendous potential to facilitate multiproxy reconstructions from this enigmatic environment
Sustainable Water Treatment with Induced Bank Filtration
Get PDFThis study demonstrates that an induced bank filter (IBF) system can treat raw water polluted with Escherichia coli (E. coli) bacteria. Similar to riverbank filtration (RBF), induced or reversed bank filtration relies on natural processes to clean water, including filtration through layers of allochthone alluvial sediments and a bioactive layer that forms on top of the filter after a ripening period. At the study site, located in Southwestern India, villagers rely on a mountain spring for their water supply. Although of generally high quality, the spring water contains E. coli bacteria (up to ~2000 MPN/100 mL). Raw water diverted from this spring was gravity-fed into the IBF system, which consisted of a (1) flow regulator, (2) pre-filter and (3) the actual IBF filter. Designed and constructed based on pilot testing of prototype filters, a full-scale filter (5 m by 7 m by 2 m) was built and its performance and maintenance requirements were studied during both the monsoon season and the dry season. The data show that the IBF significantly improved the water quality. Turbidity and E. coli concentrations were reduced to or below the detection limit (approximately 2.5 log unit reduction). During the peak of the monsoon season (August), E. coli was present in the IBF effluent after a storm destroyed the cover of the IBF tank. The IBF construction and maintenance costs were documented. Extrapolated over a 10-year period, the cost of IBF water was 3 and 10 times lower than reverse osmosis or water supplied by truck, respectively. This study demonstrates that IBF can be part of an affordable water supply system for rural villages in mountainous terrain where conventional RBF systems cannot be installed or where other water treatment technologies are out of financial reach
Usage Statistics: Project COUNTER R5 tr_b1 Report FY2022 - Book Requests (Excluding OA_Gold) by Title
No full textProject COUNTER R5 Report TR_B1 for the University of Rhode Island for the period from July 1, 2021 - June 30, 2022. The TR_B1 report is defined as Book Requests (Excluding OA_Gold). This report presents an annual total only and only includes those platforms successfully configured for automated harvesting via SUSHI.
File for download is Excel spreadsheet generated by Alma Analytics.
Results:
Total Item Requests - 92,619
Unique Title Requests - 43,01
Electro-Mechanical Joints for an Ocean Sensor Payload
Get PDFMikel Undersea Warfare Systems is a NAVY defense contractor who has presented the group with a need for an underwater joint. This joint is to provide a waterproof seal for electrical connections within the payload. This joint is to allow for easy assembly, shipping and handling of a submarine navigation system as well as withstand pressure and drag forces at the bottom of the ocean. A final spring actuated button system was to be the final design for this problem. After many redesigns of the geometry of the button, a 1 cm in diameter circular button was the final design. After manufacturing the joint from steel in the URI machine shop, the design was tested using finite element analysis to test the yield strength of the material. Though the prototype was made out of steel, the final material would be made from titanium, which was the material these simulations were run with. After manufacturing, assembly and testing were complete, the project was completed successfully as an easy to assemble joint was created that met all of the design specifications