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Offshore wind-turbine (OWT) support structures are subjected to cyclic dynamic loads with variations in loadings from wind and waves as well as the rotation of blades throughout their lifetime. The magnitude and extent of the cyclic loading can create a fatigue limit state controlling the design of support structures. In this paper, the remaining fatigue life of the support structure for a GE Haliade 6 MW fixed-bottom jacket offshore wind turbine within the Block Island Wind Farm (BIWF) is assessed. The fatigue damage to the tower and the jacket support structure using stress time histories at instrumented and non-instrumented locations are processed. Two validated finite-element models are utilized for assessing the stress cycles. The modal expansion method and a simplified approach using static calculations of the responses are employed to estimate the stress at the non-instrumented locations—known as virtual sensors. It is found that the hotspots at the base of the tower have longer service lives than the jacket. The fatigue damage to the jacket leg joints is less than 20% and 40% of its fatigue capacity during the 25-year design lifetime of the BIWF OWT, using the modal expansion method and the simplified static approach, respectively.

With support from the US National Tsunami Hazard Mitigation Program (NTHMP), the authors have been developing tsunami inundation maps for the upper US East Coast (USEC), using high-resolution numerical modeling. These maps are envelopes of maximum elevations, velocity, or momentum flux, caused by the probable maximum tsunamis identified in the Atlantic oceanic basin, including from far-field coseismic or volcanic sources, and near-field Submarine mass failures (SMFs); the latter are the object of this work. Despite clear field evidence of past large-scale SMFs within our area of interest, such as the Currituck slide complex, their magnitude, pre-failed geometry, volume, and mode of rupture are poorly known. A screening analysis based on the Monte Carlo simulations (MCS) identified areas for possible tsunamigenic SMF sources along the USEC, indicating an increased level of tsunami hazard north of Virginia, potentially surpassing the inundation generated by a typical 100-year hurricane storm surge in the region, as well as that from the most extreme far-field coseismic sources in the Atlantic; to the south, the MCS indicated that SMF tsunami hazard significantly decreased. Subsequent geotechnical and geological analyses delimited four high-risk areas along the upper USEC where the potential for large tsunamigenic SMFs, identified in the MCS, was realistic on the basis of field data (i.e., sediment nature and volume/availability). In the absence of accurate site-specific field data, following NTHMP’s recommendation, for the purpose of simulating tsunami hazard from SMF PMTs, we parameterized an extreme SMF source in each of the four areas as a so-called Currituck proxy, i.e., a SMF having the same volume, dimensions, and geometry as the historical SMF. In this paper, after briefly describing our state-of-the-art SMF tsunami modeling methodology, in a second part, we parameterize and model the historical Currituck event, including: (1) a new reconstruction of the SMF geometry and kinematics; (2) the simulation of the resulting tsunami source generation; and (3) the propagation of the tsunami source over the shelf to the coastline, in a series of nested grids. A sensitivity analysis to model and grid parameters is performed on this case, to ensure convergence and accuracy of tsunami simulation results. Then, we model in greater detail and discuss the impact of the historical Currituck tsunami event along the nearest coastline where its energy was focused, off of Virginia Beach and Norfolk, as well as near the mouth of the Chesapeake Bay; our results are in qualitative agreement with an earlier modeling study. In a third part, following the same methodology, we model tsunami generation and propagation for SMF Currituck proxy sources sited in the four identified areas of the USEC. Finally, as an illustration of our SMF tsunami hazard assessment work, we present detailed tsunami inundation maps, as well as some other products, for one of the most impacted and vulnerable areas, near and around Ocean City, MD. We find that coastal inundation from near-field SMF tsunamis may be comparable to that caused by the largest far-field sources. Because of their short propagation time and, hence, warning times, SMF tsunamis may pose one of the highest coastal hazards for many highly populated and vulnerable communities along the upper USEC, certainly comparable to that from extreme hurricanes.

Lipopolysacharride (LPS) forms the outer leaflet of the outer membrane in Gram-negative bacteria and contributes to the permeability barrier and immune response. In this study, we established a method for monitoring the LPS biosynthetic intermediates of the Raetz pathway (lpxA-lpxK) in Escherichia coli. Metabolites from compound-treated cells and genetically-perturbed cells were extracted from whole cells and concentrated by mixed-mode weak anion exchange (WAX) solid-phase extraction (SPE) prior to analysis by normal phase (NP)LC-MS/MS. Data was normalized to cell density and an internal standard prior to comparison against untreated cells in order to determine fold accumulation and depletion for affected metabolites. Using this LC-MS/MS method, we were able to reliably monitor changes in levels of the LPS intermediates in response to compound-treatment and genetic modification. In addition, we found that deletion of periplasmic CDP-diacylglycerol pyrophosphatase dramatically increased levels of the UDP-containing LPS intermediates, suggesting the enzymatic breakdown during sample preparation. This assay allows for probing a key essential pathway in Gram-negative bacteria in an effort to discover antibacterial agents that inhibit enzymes in the LPS biosynthetic pathway.

This paper presents an evaluation of inundation, erosion, and wave damage for a coastal community in Rhode Island, USA. A methodology called the Coastal Environmental Risk Index (CERI) was used that incorporates levels of inundation including sea level rise, wave heights using STWAVE, and detailed information about individual structures from an E911 database. This information was input into damage functions developed by the U.S. Army Corps of Engineers following Hurricane Sandy. Damage from erosion was evaluated separately from local published erosion rates. Using CERI, two different adaptation strategies were evaluated that included a combination of dune restoration, protective berms, and a tide gate. A total of 151 out of 708 structures were estimated to be protected from inundation and wave action by the combined measures. More importantly, the use of CERI allowed for the assessment of the impact of different adaptation strategies on both individual structures and an entire community in a Geographical Information Systems (GIS) environment. This tool shows promise for use by coastal managers to assess damage and mitigate risk to coastal communities.

Phosphorus-based land application limits for manure have increased the importance of optimizing diet P management and accurately characterizing the bioavailability of manure P. We examined the effects of pig (Sus scrofa) diets formulated with high-available-P corn and phytase on P levels in excreta and slurry stored for 30, 60, 90, 120, and 150 d. Twenty-four pigs (approximately 14 kg each) were fed one of four low-P diets: (i) normal corn, no phytase (control); (ii) normal corn with 600 phytase units kg−1 (PHY); (iii) high-available-P corn, no phytase (HAP); and (iv) high-available-P corn with 600 phytase units kg−1 (HAP + PHY). Fresh fecal and stored slurry dry matter (DM) was analyzed for total phosphorus (TP), dissolved molybdate-reactive phosphorus (DRP), dissolved organic phosphorus (DOP), acid-soluble reactive phosphorus (ASRP), acid-soluble organic phosphorus (ASOP), and phytate phosphorus (PAP). The PHY, HAP, and HAP + PHY diets significantly (α = 0.05) decreased fecal TP 19, 17, and 40%, respectively, compared with the control. Dissolved reactive P was 36% lower in the HAP + PHY diet compared with the other diets. Relative fractions (percent of TP) of DRP, DOP, ASOP, and PAP in slurry generally decreased with storage time up to 150 d, with the largest decreases occurring within 60 to 90 d. Diet-induced differences in relative fractions of DRP, DOP, ASRP, and PAP were significant when averaged across storage times, simulating a mixed-age slurry. Relative fractions of DRP in simulated mixed-age slurries were higher in HAP and HAP + PHY diets, indicating that diet may affect P losses under certain P-based application scenarios.

Frequently, well water is used instead of rainwater to perform rainfall simulations to study P and soil loss in cropping systems. This study was conducted to determine whether the source water used in simulated rainfall studies affects runoff amount and P and sediment concentrations. Rainfall simulation and natural runoff studies were conducted in a corn (Zea mays L.) and alfalfa (Medicago sativa L.) field on a Tama silt loam (fine-silty, mixed, superactive, mesic Typic Argiudoll) in spring and fall 2004. No significant differences in runoff composition were found between the well and deionized (DI) source waters in the spring rainfall simulation study in corn. The fall rain simulation in alfalfa showed significantly higher runoff volumes and dissolved reactive P (DRP) concentrations with DI water than with well water. Soil water-extractable P (WEP) measurements showed that rain and DI water extracted similar amounts of P, while well water extracted less P. Using the same source waters in WEP procedures and in rainfall simulations yielded good relationships (r2 = 0.73) between simulated rain runoff DRP and soil WEP concentrations. Natural runoff DRP concentrations measured in the same field treatments as those used in the simulated rainfall studies were much greater than those found in simulated rainfall runoff, but the relative field treatment effects on runoff P concentrations were the same. These results emphasize that simulated rainfall data can provide a relative comparison of treatment effects on runoff composition, but results from simulated rainfall experiments are not likely to duplicate natural runoff composition, regardless of the source water used.

The aim of this project is to identify new drug treatments for tuberous sclerosis complex (TSC). TSC is an autosomal dominant genetic disorder effecting 1 in 6000 births, it is characterised by the formation of hamartomas (benign tumours) throughout the body causing disfigurement, learning difficulties and organ failure. The development of new treatments is important because the current treatment, rapamycin, is severely limited, only showing a cytostatic effect on hamartoma development.Several drug candidates have been identified as potential TSC treatments using a network of SS/L interactions between Drosophila and preapproved drugs (Housden et al., 2017; Valvezan et al., 2017). I assessed these candidates in Drosophila mutant cells to identify which would be most promising as the basis for a combinatorial treatment. Lithium chloride proved to be the most effective of the candidates tested, exhibiting a selective cytotoxic effect in Drosophila TSC cells. Lithium chloride was then screened against a library of one hundred and fifty-four FDA targets identified by Housden et al (2017) to identify possible synergistic combinations.Fifteen possible candidates were identified in this screen. Three of the genes identified were related to purine synthesis, which has been identified as a potential candidate for TSC treatment before. Of these genes ras (analogous to IMPDH) has two approved drugs, Ribavirin and Mycophenolic acid (MPA), and one experimental drug, mizoribine. These drugs were tested in combination with lithium chloride in murine and human cells in order to identify possible synergistic interactions.The preliminary results in both human and murine cells suggest that the synergy identified in the screen is conserved. However, preliminary results in human cells were inconclusive. Further testing is needed to properly validate these results and to develop new treatments for TSC.

BAXTER, CHRISTOPHER ROBERT. Examining School Counselors-in-Training Self-Efficacy through a Narrative-Based Supervision Intervention. (Under the direction of Dr. Helen LuptonSmith). This single-case research design study examined the degree of change in school-counselors-in-training self-report of self-efficacy in response to a narrative-based supervision intervention using the Counselor Self-Efficacy Scale. The narrative-based supervision intervention consisted of ten prompting questions, five questions focused on the school counselor and student relationship, while the remaining five questions focused on the supervisor and supervisee relationship. Participants received the narrative-based supervision intervention across three consecutive weekly sessions each. Participants were four school counseling internship students. Results showed that participants who showed decreasing trend scores before the intervention, showed an increase in self-efficacy score at the onset of the intervention and increasing trend scores in self-efficacy throughout the intervention phase. Participants who showed increasing trend scores before intervention, showed an initial decrease in scores in self-efficacy with slight increasing trends during the intervention phase.