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Understanding the residence time, flow velocities, and storage volumes in fractured rock aquifers is essential for assessing the sustainable use of groundwater in island aquifer systems. Environmental tracers such as tritium (3H) and sulfur hexafluoride (SF6) that enter the aquifer systems through natural hydrological processes are effectively used to quantify the “apparent age” of young groundwater (<60 years) to calculate these aquifer characteristics. The island of Tobago is predominantly a fractured rock aquifer system that contains groundwater sub-basins that produce 100–1000% more than their calculated recharge. In this study, we analyzed ten samples from groundwater wells throughout the island for environmental tracers to establish the “apparent age” of the groundwater. We then estimated the active flux and storage volume of the aquifer. The 3H results of ten wells throughout the island range between 0.02 and 0.60 TU. The groundwater samples to the south of the island possess more pre-modern groundwater ages (older ages) than samples in the north of the island. These tritium values reveal age ranges between 18 and 60–plus years. This finding suggests that fractures create flow paths oriented towards the southern parts of the basin that enable the transport of groundwater across significant topographic boundaries and watershed divides. Additionally, the data may support that southern wells are connected to isolated old sources of groundwater. SF6 values range between 0.91 and 7.97 (part per trillion volume) with an interpreted age range between 18 and 39 years. Both tracers support the original hypothesis that longer residence time waters are located south of the island except for three SF6 samples which are believed to be affected by “excess air”.

Understanding the residence time, flow velocities, and storage volumes in fractured rock aquifers is essential for assessing the sustainable use of groundwater in island aquifer systems. Environmental tracers such as tritium ([sup.3]H) and sulfur hexafluoride (SF[sub.6]) that enter the aquifer systems through natural hydrological processes are effectively used to quantify the “apparent age” of young groundwater (<60 years) to calculate these aquifer characteristics. The island of Tobago is predominantly a fractured rock aquifer system that contains groundwater sub-basins that produce 100–1000% more than their calculated recharge. In this study, we analyzed ten samples from groundwater wells throughout the island for environmental tracers to establish the “apparent age” of the groundwater. We then estimated the active flux and storage volume of the aquifer. The [sup.3]H results of ten wells throughout the island range between 0.02 and 0.60 TU. The groundwater samples to the south of the island possess more pre-modern groundwater ages (older ages) than samples in the north of the island. These tritium values reveal age ranges between 18 and 60–plus years. This finding suggests that fractures create flow paths oriented towards the southern parts of the basin that enable the transport of groundwater across significant topographic boundaries and watershed divides. Additionally, the data may support that southern wells are connected to isolated old sources of groundwater. SF[sub.6] values range between 0.91 and 7.97 (part per trillion volume) with an interpreted age range between 18 and 39 years. Both tracers support the original hypothesis that longer residence time waters are located south of the island except for three SF[sub.6] samples which are believed to be affected by “excess air”.

Trinidad and Tobago is a developing two-island nation in the Lesser Antilles of the Caribbean. Tobago is the smaller island and has small highly heterogeneous aquifers composed of igneous and metamorphic crystalline rock with strong structural controls on the spatial distribution of permeability. Hydrogeologic analyses of the water budget and groundwater production suggest that portions of the island are underlain by prolific fractured-rock aquifer systems. This study quantifies the amount and spatial distribution of recharge, as well as the fraction of recharge captured by groundwater pumping, using historical data, new field data, remote sensing data, multiple storage quantification methods and stable isotope analysis. Despite extensive freshwater withdrawals, groundwater production reaches only ~10% of annual groundwater recharge. Groundwater capture zones are created using a first-order hydrologic balance approach and with backward particle tracking in a steady-state groundwater model. Both approaches to generating capture zones suggest that many wells capture water from outside their topographic watershed. The location of sustainable, high yield, fresh potable groundwater wells less than 1 km from the coast, that have fractured bedrock intakes well below sea level, supports the concept of a rigorous and active groundwater flow system. Understanding the hydrogeology of small bedrock island aquifers is critical to evaluating groundwater resources, especially in the Caribbean where there is strong seasonality in precipitation, finite surface-water storage and increases in potable water demand.

Objective: The aims of this study were to measure job satisfaction and engagement perceptions of new nurses after completing interactive residency modules and to test the reliability and validity of the Halfer-Graf Job/Work Environment Nursing Satisfaction Survey. Background: US nursing shortages are estimated to increase to 36% by 2020, requiring emphasis on hiring new graduate nurses. Improved retention of new graduates through innovative orientations such as interactive nurse residencies is one option. Methods: This mixed qualitative and quantitative study compared perceived job satisfaction and employee engagement of 90 new graduate nurses completing an interactive nurse residency. Results: Reliability and validity of the Halfer-Graf tool were supported. Qualitative analysis yielded trends related to satisfiers (patients, patient outcomes, and teamwork) and dissatisfiers (staffing/scheduling, lack of teamwork, and physician disrespect). Simulation scenarios, debriefing, and e-mail communication with peers ranked high as beneficial teaching strategies. Conclusions: Study findings support previous research. An interactive learning environment was perceived as beneficial. First and second year nurse retention was consistent with previous residency programming.

In a cold and stable space environment, the James Webb Space Telescope (JWST or \"Webb\") reaches unprecedented sensitivities at wavelengths beyond 2 microns, serving most fields of astrophysics. It also extends the parameter space of high-contrast imaging in the near and mid-infrared. Launched in late 2021, JWST underwent a six month commissioning period. In this contribution we focus on the NIRCam Coronagraphy mode which was declared \"science ready\" on July 10 2022, the last of the 17 JWST observing modes. Essentially, this mode will allow to detect fainter/redder/colder (less massive for a given age) self-luminous exoplanets as well as other faint astrophysical signal in the vicinity of any bright object (stars or galaxies). Here we describe some of the steps and hurdles the commissioning team went through to achieve excellent performances. Specifically, we focus on the Coronagraphic Suppression Verification activity. We were able to produce firm detections at 3.35\\(\\mu\\)m of the white dwarf companion HD 114174 B which is at a separation of \\(\\simeq\\) 0.5\" and a contrast of \\(\\simeq\\) 10 magnitudes (\\(10^{4}\\) fainter than the K\\(\\sim\\)5.3 mag host star). We compare these first on-sky images with our latest, most informed and realistic end-to-end simulations through the same pipeline. Additionally we provide information on how we succeeded with the target acquisition with all five NIRCam focal plane masks and their four corresponding wedged Lyot stops.

We are Realtors, and this colors our thinking.

After rising in the morning, [Steven Kirtley] would have breakfast, consisting usually of bread and butter. Then he'd read, play cards, or \"walk around in circles.\" Then lunch, the best meal of the day; \"greasy\" fried chicken and rice or \"shoe leather\" roast beef and potatoes. After lunch, he would read, play cards or \"walk in circles\" until dinner.

This work describes observations of the diffuse interstellar medium in three wavelength bands; UV (1000-1300 A covered by the Copernicus satellite), far-UV (500-1800 A from the Voyager 1 and 2 spacecrafts) and optical (3800-4300 A obtained from ground-based observations). Chapter 2 deals with abundances and depletions of elements in the ISM. Although Copernicus was limited to brighter stars we obtained abundances and elemental depletions for the lines of sight to $\\sigma$ Sco and $\\theta$ Car. We find that, for these and other lines of sight, the element-to-element depletion pattern is remarkably stable. Chapter 3 discusses extinction along the lines of sight to several O and B stars which were observed by Voyagers 1 and 2. By observing stars which were generally unreddened and comparing them to reddened stars, the interstellar extinction curve has been extended to below 1000 A. The results show that, for all of the cases we have studied, the selective extinction continues to rise toward shorter wavelengths. Chapter 4 deals with ground-based observations of CH$\\sp+$. The overabundance of CH$\\sp+$ in the ISM is a problem in that the radiative reaction rate of C$\\sp+$ and H is much too slow to give the abundances seen, and also because CH$\\sp+$ is easily destroyed. An endothermic reaction of C$\\sp+$ and H$\\sb2$ may create enough CH$\\sp+$, but it requires shock waves that provide the 0.4 eV of energy needed for the reaction to proceed. In many previous studies, the amount of CH$\\sp+$ seems to increase as E(B-V) increases, which is not what we would expect if the shock formation model is correct. However, these studies deal primarily with brighter stars with E(B-V) less than 0.5. In the work described in this chapter, we have looked at stars with E(B-V) up to +1.13, and have found that the abundance of CH$\\sp+$ does not appear to increase for more reddened stars.

The validation of candidate biomarkers often is hampered by the lack of a reliable means of assessing and comparing performance. We present here a reference set of serum and plasma samples to facilitate the validation of biomarkers for resectable pancreatic cancer. The reference set includes a large cohort of stage I-II pancreatic cancer patients, recruited from 5 different institutions, and relevant control groups. We characterized the performance of the current best serological biomarker for pancreatic cancer, CA 19-9, using plasma samples from the reference set to provide a benchmark for future biomarker studies and to further our knowledge of CA 19-9 in early-stage pancreatic cancer and the control groups. CA 19-9 distinguished pancreatic cancers from the healthy and chronic pancreatitis groups with an average sensitivity and specificity of 70-74%, similar to previous studies using all stages of pancreatic cancer. Chronic pancreatitis patients did not show CA 19-9 elevations, but patients with benign biliary obstruction had elevations nearly as high as the cancer patients. We gained additional information about the biomarker by comparing two distinct assays. The two CA 9-9 assays agreed well in overall performance but diverged in measurements of individual samples, potentially due to subtle differences in antibody specificity as revealed by glycan array analysis. Thus, the reference set promises be a valuable resource for biomarker validation and comparison, and the CA 19-9 data presented here will be useful for benchmarking and for exploring relationships to CA 19-9.

Purpose Despite rigorous evidence of improved quality of life and longer survival, disparities in the utilization of palliative and hospice care persist for racial and ethnic minority patients with cancer. This study evaluated the impact of psychosocial factors on utilization of these services. Methods Patients with advanced lung cancer were recruited at a large academic urban hospital. Patients were surveyed about their knowledge of palliative care and hospice and their beliefs regarding medical mistrust, lung cancer care, palliative care and hospice. We used univariate and multivariable logistic regression analyses to examine the association between mistrust, knowledge and beliefs among the entire cohort and minority (Black and Hispanic) and non‐minority patients on utilization of palliative care consultation and hospice care use. Results Ninety‐nine of the enrolled participants had a mean age of 64 years. Minority patients were more likely to receive a palliative care referral (p < 0.001) and attend a consult (p = 0.003). Similarly, they were more likely to receive a hospice referral (p = 0.04), however there was no difference in hospice care use based on minority status (p = 0.102). In our adjusted model, older patients and those reporting negative lung cancer beliefs were more likely to receive hospice care (OR: 1.06, 95% CI: 1.004–1.138; OR: 1.04, 95% CI: 1.002–1.093, respectively). Conclusion Minority patients with advanced lung cancer were more likely to receive a palliative care referral and specialty level consultation when compared to non‐minority patients. Our work highlights the importance of proactive referral processes in facilitating access to palliative and hospice services, particularly among younger patients.