Academic Predictors of Online Course Success in the Community College

The purpose of this study was to identify academic factors that might predict online course success for community college students. Online course success was a focus of national research and debate as studies consistently indicated lower success rates in online courses as compared to traditional courses; however, research that identified academic predictors to guide the development of policies and services that support student success in online courses was limited. A random sample of 20 online course sections held at one multi-campus, urban community college resulted in 491 enrollees being examined for seventy-eight factors that might predict online course success. Factors present prior to online course enrollment included GPA; test scores; developmental coursework in reading, writing, and mathematics; college-level coursework in specific disciplines; and enrollment history. Factors present during the semester of online course enrollment included student status, current enrollment measures such as total number of courses attempted, total credits, and course duration. Demographic factors included gender, age, race/ethnicity, financial aid status, and geographic proximity to campus. Data extracted from the student registration system included demographic characteristics, course rosters, test scores, and enrollment history. Data were grouped into three blocks prior to analysis: demographics, academic factors prior to online enrollment, and academic factors during online enrollment. An unordered logistical regression evaluated the predictive value of these factors for online course success. Results of the logistical regression analysis indicated that the predictor model did not provide a statistically significant improvement over the constant-only model; the addition of variables did not improve the ability to predict the outcome, online course success. Continued analysis identified four statistically significant predictors of online course success in community college students. For factors measured prior to enrollment, cumulative college GPA was a positive predictor of online course success. For demographic factors, geographic proximity to campus was a negative predictor of online course success. For factors present during enrollment, total courses attempted (during the semester studied) was a positive predictor, and total credits attempted (during the semester studied) was a negative predictor of online course success. The researcher concluded that online course success in community college students was a complex issue that could not be explained by academic factors alone and suggested that future studies attempting to predict online course success in community college students be comprehensive in addressing the multitude of academic, social, and other factors that may influence online course success. Additional suggestions for further study included evaluating the relationship individual factors have to online course success and seeking out student perspectives regarding online courses to determine other factors that contribute to successful and unsuccessful online course experiences for community college students

Colors of 2625 Quasars at 0<z<5 Measured in the Sloan Digital Sky Survey Photometric System

We present an empirical investigation of the colors of quasars in the Sloan Digital Sky Survey (SDSS) photometric system. The sample studied includes 2625 quasars with SDSS photometry. The quasars are distributed in a 2.5 degree wide stripe centered on the Celestial Equator covering $\sim529$ square degrees. Positions and SDSS magnitudes are given for the 898 quasars known prior to SDSS spectroscopic commissioning. New SDSS quasars represent an increase of over 200% in the number of known quasars in this area of the sky. The ensemble average of the observed colors of quasars in the SDSS passbands are well represented by a power-law continuum with $\alpha_{\nu} = -0.5$ ($f_{\nu} \propto \nu^{\alpha}$). However, the contributions of the $3000 {\rm \AA}$ bump and other strong emission lines have a significant effect upon the colors. The color-redshift relation exhibits considerable structure, which may be of use in determining photometric redshifts for quasars. The range of colors can be accounted for by a range in the optical spectral index with a distribution $\alpha_{\nu}=-0.5\pm0.65$ (95% confidence), but there is a red tail in the distribution. This tail may be a sign of internal reddening. Finally, we show that there is a continuum of properties between quasars and Seyfert galaxies and we test the validity of the traditional division between the two classes of AGN.Comment: 66 pages, 15 figures (3 color), accepted by A

Active Galactic Nuclei in the Sloan Digital Sky Survey: II. Emission-Line Luminosity Function

The emission line luminosity function of active galactic nuclei (AGN) is measured from about 3000 AGN included in the main galaxy sample of the Sloan Digital Sky Survey within a redshift range of $0<z<0.15$. The \Ha and [OIII]$\lambda 5007$ luminosity functions for Seyferts cover luminosity range of $10^{5-9}$$L_\odot$ in H$\alpha$ and the shapes are well fit by broken power laws, without a turnover at fainter nuclear luminosities. Assuming a universal conversion from emission line strength to continuum luminosity, the inferred B band magnitude luminosity function is comparable both to the AGN luminosity function of previous studies and to the low redshift quasar luminosity function derived from the 2dF redshift survey. The inferred AGN number density is approximately 1/5 of all galaxies and about $6\times 10^{-3}$ of the total light of galaxies in the $r$-band comes from the nuclear activity. The numbers of Seyfert 1s and Seyfert 2s are comparable at low luminosity, while at high luminosity, Seyfert 1s outnumber Seyfert 2s by a factor of 2-4. In making the luminosity function measurements, we assumed that the nuclear luminosity is independent of the host galaxy luminosity, an assumption we test {\it a posteriori}, and show to be consistent with the data. Given the relationship between black hole mass and host galaxy bulge luminosity, the lack of correlation between nuclear and host luminosity suggests that the main variable that determines the AGN luminosity is the Eddington ratio, not the black hole mass. This appears to be different from luminous quasars, which are most likely to be shining near the Eddington limit.Comment: AASTeX v5.02 preprint; 35 pages, including 2 table and 12 figures. To appear in the April 2005 issue of AJ. See astro-ph/0501059 for Paper

Large-Scale Absence of Sharks on Reefs in the Greater-Caribbean: A Footprint of Human Pressures

BACKGROUND: In recent decades, large pelagic and coastal shark populations have declined dramatically with increased fishing; however, the status of sharks in other systems such as coral reefs remains largely unassessed despite a long history of exploitation. Here we explore the contemporary distribution and sighting frequency of sharks on reefs in the greater-Caribbean and assess the possible role of human pressures on observed patterns. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed 76,340 underwater surveys carried out by trained volunteer divers between 1993 and 2008. Surveys were grouped within one km2 cells, which allowed us to determine the contemporary geographical distribution and sighting frequency of sharks. Sighting frequency was calculated as the ratio of surveys with sharks to the total number of surveys in each cell. We compared sighting frequency to the number of people in the cell vicinity and used population viability analyses to assess the effects of exploitation on population trends. Sharks, with the exception of nurse sharks occurred mainly in areas with very low human population or strong fishing regulations and marine conservation. Population viability analysis suggests that exploitation alone could explain the large-scale absence; however, this pattern is likely to be exacerbated by additional anthropogenic stressors, such as pollution and habitat degradation, that also correlate with human population. CONCLUSIONS/SIGNIFICANCE: Human pressures in coastal zones have lead to the broad-scale absence of sharks on reefs in the greater-Caribbean. Preventing further loss of sharks requires urgent management measures to curb fishing mortality and to mitigate other anthropogenic stressors to protect sites where sharks still exist. The fact that sharks still occur in some densely populated areas where strong fishing regulations are in place indicates the possibility of success and encourages the implementation of conservation measures

Meta-analysis of genome-wide association studies of HDL cholesterol response to statins

BACKGROUND: In addition to lowering low density lipoprotein cholesterol (LDL-C), statin therapy also raises high density lipoprotein cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation.METHODS AND RESULTS: We performed a meta-analysis of genome-wide association studies (GWAS) to identify variants with an effect on statin-induced high density lipoprotein cholesterol (HDL-C) changes. The 123 most promising signals with p&lt;1×10(-4) from the 16 769 statin-treated participants in the first analysis stage were followed up in an independent group of 10 951 statin-treated individuals, providing a total sample size of 27 720 individuals. The only associations of genome-wide significance (p&lt;5×10(-8)) were between minor alleles at the CETP locus and greater HDL-C response to statin treatment.CONCLUSIONS: Based on results from this study that included a relatively large sample size, we suggest that CETP may be the only detectable locus with common genetic variants that influence HDL-C response to statins substantially in individuals of European descent. Although CETP is known to be associated with HDL-C, we provide evidence that this pharmacogenetic effect is independent of its association with baseline HDL-C levels.</p

Pharmacogenetic meta-analysis of genome-wide association studies of LDL cholesterol response to statins

Statins effectively lower LDL cholesterol levels in large studies and the observed interindividual response variability may be partially explained by genetic variation. Here we perform a pharmacogenetic meta-analysis of genome-wide association studies (GWAS) in studies addressing the LDL cholesterol response to statins, including up to 18,596 statin-treated subjects. We validate the most promising signals in a further 22,318 statin recipients and identify two loci, SORT1/CELSR2/PSRC1 and SLCO1B1, not previously identified in GWAS. Moreover, we confirm the previously described associations with APOE and LPA. Our findings advance the understanding of the pharmacogenetic architecture of statin response

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Functional and quality of life outcomes of localised prostate cancer treatments (prostate testing for cancer and treatment [ProtecT] study)

Objective To investigate the functional and quality of life (QoL) outcomes of treatments for localised prostate cancer and inform treatment decision-making. Patients and Methods Men aged 50–69 years diagnosed with localised prostate cancer by prostate-specific antigen testing and biopsies at nine UK centres in the Prostate Testing for Cancer and Treatment (ProtecT) trial were randomised to, or chose one of, three treatments. Of 2565 participants, 1135 men received active monitoring (AM), 750 a radical prostatectomy (RP), 603 external-beam radiotherapy (EBRT) with concurrent androgen-deprivation therapy (ADT) and 77 low-dose-rate brachytherapy (BT, not a randomised treatment). Patient-reported outcome measures (PROMs) completed annually for 6 years were analysed by initial treatment and censored for subsequent treatments. Mixed effects models were adjusted for baseline characteristics using propensity scores. Results Treatment-received analyses revealed different impacts of treatments over 6 years. Men remaining on AM experienced gradual declines in sexual and urinary function with age (e.g., increases in erectile dysfunction from 35% of men at baseline to 53% at 6 years and nocturia similarly from 20% to 38%). Radical treatment impacts were immediate and continued over 6 years. After RP, 95% of men reported erectile dysfunction persisting for 85% at 6 years, and after EBRT this was reported by 69% and 74%, respectively (P < 0.001 compared with AM). After RP, 36% of men reported urinary leakage requiring at least 1 pad/day, persisting for 20% at 6 years, compared with no change in men receiving EBRT or AM (P < 0.001). Worse bowel function and bother (e.g., bloody stools 6% at 6 years and faecal incontinence 10%) was experienced by men after EBRT than after RP or AM (P < 0.001) with lesser effects after BT. No treatment affected mental or physical QoL. Conclusion Treatment decision-making for localised prostate cancer can be informed by these 6-year functional and QoL outcomes

Ecological Risk Assessment of Managed Relocation as a Climate Change Adaptation Strategy

Executive Summary Changing climate and introduced species are placing an increasing number of species at risk of extinction. Increasing extinction risk is increasing calls to protect species by relocating, or translocating, them to locations with more favorable biotic or climatic conditions. Managed relocation, or assisted migration, of species entails risks to both the conservation target organisms being moved as well as the recipient ecosystems into which they are moved. Recognizing this risk, calls have been made for practitioners interested in considering a managed relocation project to engage in a serious risk assessment prior to advancing a project. We engaged a team of researchers and resource managers to create risk assessment protocols that could be used by natural resource managers within U.S. National Parks, or elsewhere, to help inform a decision of whether the risks involved in managed relocation are warranted. These protocols facilitate evaluation of the ecological risk of species managed relocation as part of planning and decision making. This is not a policy document. It neither introduces new policy, nor serves to interpret or resolve current policies regarding managed relocation (or assisted migration) as a natural resource management strategy. We assembled a team of five university researchers and ten federal resource management researchers and staff to develop a practical management-oriented risk assessment strategy. We jointly agreed to a set of principles to guide this managed relocation risk assessment strategy. This protocol and accompanying spreadsheet would be used to help a decision-maker structure a decision process but would not strive to provide a formulaic decision output. Identifying, evaluating, and managing risk is a subjective decision that is the responsibility of the decision authority. We began by defining the scope of this work to include moving populations or species for the purpose of conserving the target populations or species that are threatened by climate or invasive species. We also included species movements for the purpose of retaining some critical ecosystem function. We did not include management actions such as planned ecosystem re-alignment for climate change or other kinds of translocations associated with ecosystem manipulation (e.g., habitat restoration), although these protocols may be useful for some of those management actions with minor modification. We adopted the premise that risk decisions are inherently subjective and that different aspects of risk (e.g. the risk of a moved species introducing a novel pathogen to an ecosystem, the risk of unwanted evolution in the moved species) are non-additive. Hence, our strategy is designed to encourage managers to think broadly and comprehensively about risk in order to make the best possible decision given alternate opposing risks (i.e. the risk of extinction versus the risk of causing unintended harm to other species and ecosystems in the process of trying to save a species). We identified six major areas of risk, with a total of seventeen sub-categories. These are: • Risks of no managed relocation action. Risk of: o no action on the target o no action on the recipient ecosystem • Risks of managed relocation action to the target. Risks of: o action on the translocated individuals o target source population extirpation through diminished numbers o reduced ecological functioning of the source ecosystem o causing undesired evolution in the target • Risks of action on non-targets in the recipient ecosystem. Risks of: o target transmitting novel disease or associated pest o negative competitive interactions on non-target populations o predation, herbivory, or allelopathic effects on non-target populations o driving undesirable evolution in non-target species • Risks of action on higher order attributes of the recipient ecosystem. Risks of: o indirect and negative impacts on ecosystem structure o changing ecosystem function • Risks associated with invasion. Risks of: o invasion within the intended recipient ecosystem o invasion beyond recipient ecosystem o irreversibility of the managed relocation action • Risks associated with socio-economic values. Risks to: o culturally or economically important species o valued ecosystem services For each risk category we provide guidance on risk scoring. Risk scoring is comprised of a risk rank category (low, moderate, high, very high) and a confidence score (low, medium, high). Confidence is a combined attribute of the strength of evidence and the agreement of that evidence. The protocols are presented in an accompanying Excel spreadsheet that uses a graphical tool to allow users to visualize a composite of risk and confidence. We are adamant about not summing across risk categories. Instead, we provide a graphing tool that summarizes risk within categories. We suggest that users could find risks posed by a proposed action to be acceptable if: 1) Confidence scores are sufficient that managers feel confident that the risk assessment is informative; 2) There is no single risk category that is so high and so important as to make the project unacceptably risky; and 3) The general distribution of risk is not so high as to exceed some level of expectation that one of many potential problems could arise and lead to decision regret. We frame this risk assessment within the context of other critical questions that need to be answered in order to proceed toward strategic planning for a managed relocation action. These include justifying ecological need, assessing technical feasibility, cost, management priority and social acceptability. If all these criteria are met, then these same protocols can be used in a multi-criteria assessment to compare across different strategic plans for managed relocation (e.g. relocation location, relocation numbers, source and husbandry of relocated individuals). We provide brief guidance on how that may be completed with no presumption of final decision determination. Finally, in the process of developing these risk scoring protocols, we tested them on a suite of four case studies (bull trout, Karner blue butterfly, giant sequoia and Pitcher’s thistle). These are provided in this document as examples of the logic and process that we outline for assessing risk. These were, however, done without broad consultation and should be taken not as definitive risk assessments of managed relocation for these species, but as examples of how one might use our strategy for an assessment of ecological risk associated with managed relocation