Development of a model for predicting NASA/MSFC program success

Research conducted during the execution of a previous contract (NAS8-36955/0039) firmly established the feasibility of developing a tool to aid decision makers in predicting the potential success of proposed projects. The final report from that investigation contains an outline of the method to be applied in developing this Project Success Predictor Model. As a follow-on to the previous study, this report describes in detail the development of this model and includes full explanation of the data-gathering techniques used to poll expert opinion. The report includes the presentation of the model code itself

Running Out: Food Insecurity in the LGBT Older Adult Community

While food insecurity has been shown to affect Americans across the lifespan, older adults, defined as individuals over age 65, have one of the highest subpopulation rates of food insecurity. Approximately one out of ten senior only households experience food insecurity nationally (Rabbitt, et al., 2017; Chung et al., 2012). A smaller, less researched faction of the older adult population is the lesbian, gay, bisexual and transgender (LGBT) older adult community. Research has shown that LGBT seniors are significantly poorer than their heterosexual counterparts (Emlet, 2016). LGBT older Americans also experience higher rates of isolation and lower rates of familial and other social support as LGBT seniors are three times more likely to enter older adulthood without having children nor a spouse (Goldberg & Mawn, 2014). Research on general food insecurity has uncovered that low income and reduced social support have been defining indicators for experiencing food insecurity (Rabbitt, et al., 2017) However, less is known regarding food access challenges faced by older adults who identify as LGBT. This qualitative study explores the experiences of ten LGBT older adult community members who self-identify as food insecure. All interviews were audiotaped, transcribed verbatim, and analyzed using common coding techniques. Results highlighted a variety of barriers that limited access and multiple enabling factors. A key finding is the need for food programs that take into account the needs of the older adult population, particularly in regards to food access for individuals with mobility issues. The results can inform program implementation and evaluation to make food access programs equally as effective for older program participants

The seasonal and spatial dynamics in the phytomacrofaunal communities of Lake Henley, Mastert : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey Universityon

Spatial and seasonal dynamics of macrophyte beds in Lake Henley, a shallow artificial lake in Masterton, were examined between June 1993 and June 1994. Observed fluctuations in macrophyte biomass were linked with changes in filamentous algae associated with the weed beds. Invertebrate communities associated with submerged macrophytes were also examined at multiple sites between June 1993 and June 1994. Overall community composition was related more to seasonal influences than differences between sites within the lake. However, species richness and abundance did differ spatially. Recommendations for the ongoing management of Lake Henley, including management of the macrophyte beds and the maintenance of water quality and quantity, are made with respect to the ecological characteristics of the lake. The influence of trophic status on macrophyte invertebrate communities was also explored with a survey conducted in May 1994 of 13 other lakes in the North Island. Nutrient enriched lakes were characterised by phytomacrofaunal communities with high abundance and higher numerical dominance, whereas nutrient poor lake phytomacrofaunal communities were characterised by lower abundances but higher diversity of some taxonomic groups, particularly insects

Great expectations? A qualitative study of health professionals' perspectives on breaking bad news about rehabilitation potential after traumatic brain injury or spinal injury

Background: Neurorehabilitation units play an important role in facilitating recovery for those with complex needs following a neurological event. National guidance highlights the importance of providing patients and their families with information and fostering realistic expectations. This may involve the breaking of bad news. The aim of this study is to explore health professionals’ perspectives on breaking bad news in the neurorehabilitation setting. Method: 15 health professionals (physiotherapists, occupational therapists, nurses, speech therapists, psychologists and doctors) working at a 24 bedded neurorehabilitation unit in a National Health Service acute trust in England were recruited. A qualitative study was conducted using patient vignettes to facilitate discussions during semi-structured interviews and a focus group. The results were analysed using thematic analysis. Results: Four major themes emerged: influencing factors, current approaches used, staff experiences, and strategies to improve breaking bad news. There was a need for better management of patients' and families' expectations. Breaking bad news was seen as emotionally demanding yet often unrecognised work. Conclusions: Breaking bad news in the neurorehabilitation setting is complex and under-recognised work, involving multiple health professionals. There is a need for both experience and training to improve skills and confidence in breaking bad news

Is There a Right Way to Teach Physics?

An important development in university physics teaching in the last two decades has been the emergence of a world-wide Physics Education Research community. In physics departments at relatively large numbers of institutions throughout the world, particularly the USA and Europe, academic physicists are doing research into the difficulties associated with teaching their subject. Among the many directions this research has taken is the identification of "misconceptions" (sometimes referred to as "alternative conceptions"). These are ideas or concepts which students have constructed for themselves, based on their own experience of the natural world, which are often in conflict with the agreed view of practicing scientists. Research has shown that these "misconceptions" are very widely shared, very often in conflict with other concepts the student holds, and very difficult to change. Following on from this research, as it were, a lot of work has been done to develop special diagnostic tests to uncover which, if any, of these misconceptions particular students hold. They normally consist of series of multiple choice questions, in which the "right" answer is hidden among very tempting distracters, each one targeting one or more common misconceptions. Among the best known of these tests, in the subject area of kinematics and dynamics, are the Force Concept Inventory (FCI) and the Force and Motion Conceptual Evaluation (FMCE). This research has, in turn, prompted the development of teaching strategies which target specific classes of misconceptions - in the (understandable) belief that, if students can get the fundamental concepts "right", they have a better chance of understanding the rest of the subject. The results of these strategies are reported in the literature, and there is coming to be a consensus within the physics education community that, for example, traditional (chalk and talk, lectures plus laboratories) teaching is relatively ineffective in changing misconceptions. On the other hand, one recent survey of over 7000 students in the USA has shown that teaching which employs interactive methods can result in significant increases in understanding (as measured by these diagnostic tests). It would seem important therefore that teachers everywhere should take these findings seriously, and, where possible, test whether the same gain in understanding can be achieved in other teaching contexts

Dynamical Friction in dE Globular Cluster Systems

The dynamical friction timescale for globular clusters to sink to the center of a dwarf elliptical galaxy (dE) is significantly less than a Hubble time if the halos have King-model or isothermal profiles and the globular clusters formed with the same radial density profile as the underlying stellar population. We examine the summed radial distribution of the entire globular cluster systems and the bright globular cluster candidates in 51 Virgo and Fornax Cluster dEs for evidence of dynamical friction processes. We find that the summed distribution of the entire globular cluster population closely follows the exponential profile of the underlying stellar population. However, there is a deficit of bright clusters within the central regions of dEs (excluding the nuclei), perhaps due to the orbital decay of these massive clusters into the dE cores. We also predict the magnitude of each dE's nucleus assuming the nuclei form via dynamical friction. The observed trend of decreasing nuclear luminosity with decreasing dE luminosity is much stronger than predicted if the nuclei formed via simple dynamical friction processes. We find that the bright dE nuclei could have been formed from the merger of orbitally decayed massive clusters, but the faint nuclei are several magnitudes fainter than expected. These faint nuclei are found primarily in M_V > -14 dEs which have high globular cluster specific frequencies and extended globular cluster systems. In these galaxies, supernovae-driven winds, high central dark matter densities, extended dark matter halos, the formation of new star clusters, or tidal interactions may act to prevent dynamical friction from collapsing the entire globular cluster population into a single bright nucleus.Comment: 15 pages, 2 tables, 7 figures; to appear in the Astrophysical Journal, April 20, 200

Nitrate and nitrite contamination in drinking water and cancer risk: A systematic review with meta-analysis

BACKGROUND: Pollution of water sources, largely from wide-scale agricultural fertilizer use has resulted in nitrate and nitrite contamination of drinking water. The effects on human health of raised nitrate and nitrite levels in drinking water are currently unclear. OBJECTIVES: We conducted a systematic review of peer-reviewed literature on the association of nitrate and nitrite in drinking water with human health with a specific focus on cancer. METHODS: We searched eight databases from 1 January 1990 until 28 February 2021. Meta-analyses were conducted when studies had the same exposure metric and outcome. RESULTS: Of 9835 studies identified in the literature search, we found 111 studies reporting health outcomes, 60 of which reported cancer outcomes (38 case-control studies; 12 cohort studies; 10 other study designs). Most studies were set in the USA (24), Europe (20) and Taiwan (14), with only 3 studies from low and middle-income countries. Nitrate exposure in water (59 studies) was more commonly investigated than nitrite exposure (4 studies). Colorectal (15 studies) and gastric (13 studies) cancers were the most reported. In meta-analyses (4 studies) we identified a positive association of nitrate exposure with gastric cancer, OR = 1.91 (95%CI = 1.09-3.33) per 10 mg/L increment in nitrate ion. We found no association of nitrate exposure with colorectal cancer (10 studies; OR = 1.02 [95%CI = 0.96-1.08]) or cancers at any other site. CONCLUSIONS: We identified an association of nitrate in drinking water with gastric cancer but with no other cancer site. There is currently a paucity of robust studies from settings with high levels nitrate pollution in drinking water. Research into this area will be valuable to ascertain the true health burden of nitrate contamination of water and the need for public policies to protect human health

Extinction in Star-Forming Disk Galaxies from Inclination-Dependent Composite Spectra

Extinction in galaxies affects their observed properties. In scenarios describing the distribution of dust and stars in individual disk galaxies, the amplitude of the extinction can be modulated by the inclination of the galaxies. In this work we investigate the inclination dependency in composite spectra of star-forming disk galaxies from the Sloan Digital Sky Survey Data Release 5. In a volume-limited sample within a redshift range 0.065-0.075 and a r-band Petrosian absolute magnitude range -19.5 to -22 which exhibits a flat distribution of inclination, the inclined relative to face-on extinction in the stellar continuum is found empirically to increase with inclination in the g, r, and i bands. Within the central 0.5 intrinsic half-light radius of the galaxies, the g-band relative extinction in the stellar continuum for the highly-inclined objects (axis ratio b/a = 0.1) is 1.2 mag, agreeing with previous studies. The extinction curve of the disk galaxies is given in the restframe wavelengths 3700-8000 angstrom, identified with major optical emission and absorption lines in diagnostics. The Balmer decrement remains constant with inclination, suggesting a different kind of dust configuration and/or reddening mechanism in the HII region from that in the stellar continuum. One factor is shown to be the presence of spatially non-uniform interstellar extinction, presumably caused by clumped dust in the vicinity of the HII region.Comment: To appear in the Astrophysical Journa