Modern Frontiers

The most common grievance of our generation is that of the lack of frontiers. Our forefathers had unknown lands to develop, unknown oceans to cross, and unknown lands to civilize. Our complaint is that everything worth doing has already been done. With few exceptions, the whole world has been explored and settled and more or less civilized; our oceans have been charted; our industries have been highly developed. Where do we go now

JT9D performance deterioration results from a simulated aerodynamic load test

The results of testing to identify the effects of simulated aerodynamic flight loads on JT9D engine performance are presented. The test results were also used to refine previous analytical studies on the impact of aerodynamic flight loads on performance losses. To accomplish these objectives, a JT9D-7AH engine was assembled with average production clearances and new seals as well as extensive instrumentation to monitor engine performance, case temperatures, and blade tip clearance changes. A special loading device was designed and constructed to permit application of known moments and shear forces to the engine by the use of cables placed around the flight inlet. The test was conducted in the Pratt & Whitney Aircraft X-Ray Test Facility to permit the use of X-ray techniques in conjunction with laser blade tip proximity probes to monitor important engine clearance changes. Upon completion of the test program, the test engine was disassembled, and the condition of gas path parts and final clearances were documented. The test results indicate that the engine lost 1.1 percent in thrust specific fuel consumption (TSFC), as measured under sea level static conditions, due to increased operating clearances caused by simulated flight loads. This compares with 0.9 percent predicted by the analytical model and previous study efforts

Do Homebuyers Care about the 'Quality' of Natural Habitats?

We study if homebuyers in Tucson, Arizona care about the condition of natural habitats and if they have preferences between natural and manmade habitats. Using field work data we examine whether homebuyers willingness to pay is influenced by the biological condition of the neighboring riparian habitat and how homebuyers value alternative manmade green areas, specifically golf courses. We also explore the relationship between the field data and remote sensing vegetation indices. The results of a hedonic analysis of houses that sold within 0.2 miles of 51 stratified-random selected riparian survey sites in Tucson, Arizona reveals that homebuyers significantly value habitat quality and negatively value manmade park-like features. Homebuyers are willing to pay twenty percent more to live near a riparian corridor that is densely vegetated and contains more shrub and tree species, particularly species that are dependent on perennial water flow. These environmental premiums are significant, outweighing structural factors such as an additional garage or swimming pool. Likewise, proximity to a riparian habitat with low biological quality or to a golf course lowers property values.Land Economics/Use,

Au Fe vs Cu thermocouples

A calibration of gold iron thermocouples is given

Improving Access to Physical Activity: Revitalizing the Old Kona Airport Walking/Jogging Path

Environmental approaches to increase access to physical activity facilities are recommended for promoting physical activity. People with easy access to recreational facilities are more likely to achieve the recommended levels of physical activity, and neighborhoods that are walkable and provide access to public parks and jogging trails are associated with higher levels of activity. Friends for Fitness, a grassroots organization in West Hawai‘i spearheaded a community-based planning process and intervention to revitalize the Old Kona Airport into a walking/jogging trail. Through community engagement, support from local media and businesses, and volunteers, Friends for Fitness succeeded in increasing physical activity among residents. After three years, the number of walkers utilizing the trail increased more than 20%

Perceived Readiness for Hospital Discharge in Adult Medical-Surgical Patients

Purpose: The purpose of the study was to identify predictors and outcomes of adult medical-surgical patients\u27 perceptions of their readiness for hospital discharge. Design: A correlational, prospective, longitudinal design with path analyses was used to explore relationships among transition theory-related variables. Setting: Midwestern tertiary medical center. Sample: 147 adult medical-surgical patients. Methods: Predictor variables included patient characteristics, hospitalization factors, and nursing practices that were measured prior to hospital discharge using a study enrollment form, the Quality of Discharge Teaching Scale, and the Care Coordination Scale. Discharge readiness was measured using the Readiness for Hospital Discharge Scale administered within 4 hours prior to discharge. Outcomes were measured 3 weeks postdischarge with the Post-Discharge Coping Difficulty Scale and self-reported utilization of health services. Findings: Living alone, discharge teaching (amount of content received and nurses\u27 skill in teaching delivery), and care coordination explained 51% of readiness for discharge score variance. Patient age and discharge readiness explained 16% of variance in postdischarge coping difficulty. Greater readiness for discharge was predictive of fewer readmissions. Conclusions: Quality of the delivery of discharge teaching was the strongest predictor of discharge readiness. Study results provided support for Meleis\u27 transitions theory as a useful model for conceptualizing and investigating the discharge transition. Implications for Practice: The study results have implications for the CNS role in patient and staff education, system building for the postdischarge transition, and measurement of clinical care outcomes

Biofilm and Cell Adhesion Strength on Dental Implant Surfaces via the Laser Spallation Technique

OBJECTIVE: The aims of this study are to quantify the adhesion strength differential between an oral bacterial biofilm and an osteoblast-like cell monolayer to a dental implant-simulant surface and develop a metric that quantifies the biocompatible effect of implant surfaces on bacterial and cell adhesion. METHODS: High-amplitude short-duration stress waves generated by laser pulse absorption are used to spall bacteria and cells from titanium substrates. By carefully controlling laser fluence and calibration of laser fluence with applied stress, the adhesion difference between Streptococcus mutans biofilms and MG 63 osteoblast-like cell monolayers on smooth and rough titanium substrates is obtained. The ratio of cell adhesion strength to biofilm adhesion strength (i.e., Adhesion Index) is determined as a nondimensionalized parameter for biocompatibility assessment. RESULTS: Adhesion strength of 143 MPa, with a 95% C.I. (114, 176), is measured for MG 63 cells on smooth titanium and 292 MPa, with a 95% C.I. (267, 306), on roughened titanium. Adhesion strength for S. mutans on smooth titanium is 320 MPa, with a 95% C.I. (304, 333), and remained relatively constant at 332 MPa, with a 95% C.I. (324, 343), on roughened titanium. The calculated Adhesion Index for smooth titanium is 0.451, with a 95% C.I. (0.267, 0.622), which increased to 0.876, with a 95% C.I. (0.780, 0.932), on roughened titanium. SIGNIFICANCE: The laser spallation technique provides a platform to examine the tradeoffs of adhesion modulators on both biofilm and cell adhesion. This tradeoff is characterized by the Adhesion Index, which is proposed to aid biocompatibility screening and could help improve implantation outcomes. The Adhesion Index is implemented to determine surface factors that promote favorable adhesion of cells greater than biofilms. Here, an Adhesion Index ≫ 1 suggests favorable biocompatibility

Coupling groundwater and riparian vegetation models to assess effects of reservoir releases

Although riparian areas in the arid southwestern United States are critical for maintaining species diversity, their extent and health have been declining since Euro-American settlement. The purpose of this study was to develop a methodology to evaluate the potential for riparian vegetation restoration and groundwater recharge. A numerical groundwater flow model was coupled with a conceptual riparian vegetation model to predict hydrologic conditions favorable to maintaining riparian vegetation downstream of a reservoir. A Geographic Information System(GIS) was used for this one-way coupling. Constant and seasonally varying releases from the dam were simulated using volumes anticipated to be permitted by a regional water supplier. Simulations indicated that seasonally variable releases would produce surface flow 5.4-8.5 km below the dam in a previously dry reach. Using depth to groundwater simulations from the numerical flow model with conceptual models of depths to water necessary for maintenance of riparian vegetation, the GIS analysis predicted a 5- to 6.5-fold increase in the area capable of sustaining riparian vegetation

Disease mapping of early- and late-stage cancer to monitor inequalities in early detection: a study of cutaneous malignant melanoma

We consider disease mapping of early- and late-stage cancer, in order to identify and monitor inequalities in early detection. Our method is demonstrated by mapping cancer incidence at high geographical resolution using data on 10,302 cutaneous malignant melanoma (CMM) cases within the 3.7 million population of South-West Sweden. The cases were geocoded into small-areas, each with a population size between 600 and 2600 and accessible socio-demographic data. Using the disease mapping application Rapid Inquiry Facility (RIF) 4.0, we produced regional maps to visualise spatial variations in stage I, II and III–IV CMM incidences, complemented by local maps to explore the variations within two urban areas. Pronounced spatial disparities in stage I CMM incidence were revealed by the regional and local maps. Stage I CMM incidence was markedly higher in wealthier small-areas, in particular within each urban area. A twofold higher stage I incidence was observed, on average, in the wealthiest small-areas (upper quintile) than in the poorest small-areas (lower quintile). We identified in the regional map of stage III–IV CMM two clusters of higher or lower than expected late-stage incidences which were quite distinct from those identified for stage I. In conclusion, our analysis of CMM incidences supported the use of this method of cancer stage incidence mapping for revealing geographical and socio-demographic disparities in cancer detection