Research in Economic Education: Five New Initiatives

Research is essential for improvement in teaching and learning economics. William E. Becker et al. (1991) called for new research on the relative merits of multiple-choice and essay tests, on the lasting effects of course work in economics, and on the effects of instructors, instructional techniques, and new technologies on student learning. To respond to the call, the Committee on Economic Education (CEE) of the American Economic Association recruited Robin Bartlett, William Becker, W. Lee Hansen, Peter Kennedy, and the authors to organize a conference that would jump-start new research projects

Peculiar Multimodality on the Horizontal Branch of the Globular Cluster NGC 2808

We present distributions of colors of stars along the horizontal branch of the globular cluster NGC 2808, from Hubble Space Telescope WFPC2 imaging in B, V, and an ultraviolet filter (F218W). This cluster's HB is already known to be strongly bimodal, with approximately equal-sized HB populations widely separated in the color-magnitude diagram. Our images reveal a long blue tail with two gaps, for a total of four nearly distinct HB groups. These gaps are very narrow, corresponding to envelope-mass differences of only \sim 0.01 Msun. This remarkable multimodality may be a signature of mass-loss processes, subtle composition variations, or dynamical effects; we briefly summarize the possibilities. The existence of narrow gaps between distinct clumps on the HB presents a challenge for models that attempt to explain HB bimodality or other peculiar HB structures.Comment: LaTeX, including compressed figures. To appear in ApJL. Larger (851k) PostScript version, including high-quality figures, available from http://astro.berkeley.edu/~csosin/pub

First Wave Survey Results: A Preliminary Evaluation of Chicagos Ten Year Plan to End Homelessness

2ExecutiveSummaryThis report contains preliminary information about services to homeless clients in Chicago. The information is part of a comprehensive attempt to evaluate Chicago's Ten Year Plan to End Homelessness, a plan endorsed by Chicago's Mayor in 2003 and first outlined in Getting Housed, Staying Housed: Chicago's Ten Year Plan to End Homelessness (Chicago Continuum of Care, 2000). In brief, the Plan calls for the implementation of a Housing First approach, under which clients are provided housing as soon as possible. Services are provided under the approach, but access to housing does not depend on the use of services.While the homeless service system is complex, offering services ranging from outreach and engagement to transportation to housing, this report focuses on and summarizes findings from the first of a three wave survey of clients residing in the three housing options that are provided under the Plan: emergency shelters, interim housing programs, and supportive permanent housing programs. Shelters generally house clients for a night at a time and are deemed to offer temporary placements. Interim housing programs offer accommodations to clients for a period that can last up to between 90 to 120 days. These programs generally are charged with providing linkage to services needed to address client problems, assessing clients for appropriate housing options and helping clients obtain the financial resources needed to afford housing. Supportive permanent housing programs allow people to stay as long as they wish and are charged with locating wraparound services for their clients. While they may not be unprecedented, the interim and permanent supportive housing programs are innovations suggested by the Plan.During 2009 and using a stratified, two-stage design, the first wave survey sampled a random sample of adult clients in the three types of programs. When surveying families, the head of the family was the respondent. The final sample includes 554 individuals and family heads. Of this total, 185 are from overnight shelter programs, 192 from interim housing programs and 177 from what for the purposes of this report are called permanent housing programs. The report summarizes basic findings about the surveyed clients. It analyzes the frequency with which clients evince certain traits or circumstances by the type of program. It also compares the frequencies across program types. In general, results of the analyses suggest that there has been considerable progress toward the goals of the Ten-Year Plan. The Plan's innovative programs, that is, interim and permanent housing programs, focus on clients who have long histories of homelessness. Those programs also reportedly engage in many required activities. Respondents also rate those programs higher than they rate shelters and report that agency and city workers tend to refer the clients to the new programs rather than to the old ones. On the other hand, service provision appears to be uneven in all types of programs. At the same time, largely due to policies and funding opportunities, the programs vary in the clients they serve

Discovery of Extended Blue Horizontal Branches in Two Metal-Rich Globular Clusters

We have used WFPC2 to construct B, V color-magnitude diagrams of four metal-rich globular clusters, NGC 104 (47 Tuc), NGC 5927, NGC 6388, and NGC 6441. All four clusters have well populated red horizontal branches (RHB), as expected for their metallicity. However, NGC 6388 and 6441 also exhibit a prominent blue HB (BHB) extension, including stars reaching as faint in V as the turnoff luminosity. This discovery demonstrates directly for the first time that a major population of hot HB stars can exist in old, metal-rich systems. This may have important implications for the interpretation of the integrated spectra of elliptical galaxies. The cause of the phenomenon remains uncertain. We examine the possibility that NGC 6388 and 6441 are older than the other clusters, but a simple difference in age may not be sufficient to produce the observed distributions along the HB. The high central densities in NGC 6388 and 6441 suggest that the existence of the blue HB (BHB) tails might be caused by stellar interactions in the dense cores of these clusters, which we calculate to have two of the highest collision rates among globular clusters in the Galaxy. Tidal collisions might act in various ways to enhance loss of envelope mass, and therefore populate the blue side of the HB. However, the relative frequency of tidal collisions does not seem large enough (compared to that of the clusters with pure RHBs) to account for such a drastic difference in HB morphology. While a combination of an age difference and dynamical interactions may help, prima facie the lack of a radial gradient in the BHB/RHB star ratio seems to argue against dynamical effects playing a role.Comment: LaTeX, includes one Postscript figure. To appear in ApJ

Left Ventricular Systolic Dysfunction in Rheumatoid Disease An Unrecognized Burden?

ObjectivesThis study sought to ascertain whether left ventricular systolic dysfunction (LVSD) is more common among clinic patients with rheumatoid disease (RD) compared with the general population, and to assess the diagnostic utility of brain natriuretic peptide (BNP).BackgroundPatients with RD are at increased risk of ischemic heart disease. However, there are few large echocardiographic studies identifying cardiac dysfunction in RD. We hypothesized that LVSD would be more prevalent in RD patients than in the general population.MethodsA total of 226 hospital out-patients with RD (65% women) underwent clinical evaluation, electrocardiography (ECG), echocardiography, and plasma BNP assay (218 patients). Prevalence of LVSD was compared with local population estimates.ResultsDefinite LVSD (left ventricular ejection fraction <40%) occurred in 5.3% of the RD group: standardized prevalence ratio, 3.20; 95% confidence interval, 1.65 to 5.59. Median BNP values were higher in patients with LVSD compared with those without: 16.6 pmol/l versus 8.5 pmol/l, p < 0.005, although values between the two groups overlapped. One in nine patients with an abnormal ECG had definite LVSD.ConclusionsDefinite LVSD was three times more common in RD patients than in the general population. Given the prognostic benefits of treating LVSD, echocardiographic screening of RD patients with an abnormal ECG may be worthwhile

Simulated Anthrax Attacks and Syndromic Surveillance

Bioterrorism surveillance systems can be assessed using modeling to simulate real-world attacks

Rationale and study design of a cross sectional study documenting the prevalence of Heart Failure amongst the minority ethnic communities in the UK: the E-ECHOES Study (Ethnic - Echocardiographic Heart of England Screening Study)

Background: Heart failure is an important cause of cardiovascular morbidity and mortality. Studies to date have not established the prevalence heart failure amongst the minority ethnic community in the UK. The aim of the E-ECHOES (Ethnic - Echocardiographic Heart of England Screening Study) is to establish, for the first time, the community prevalence and severity of left ventricular systolic dysfunction (LVSD) and heart failure amongst the South Asian and Black African-Caribbean ethnic groups in the UK.Methods/Design: This is a community based cross-sectional population survey of a sample of South Asian (i.e. those originating from India, Pakistan, Bangladesh) and Black African-Caribbean male and female subjects aged 45 years and over. Data collection undertaken using a standardised protocol comprising a questionnaire incorporating targeted clinical history taking, physical examination, and investigations with resting electrocardiography and echocardiography; and blood sampling with consent. This is the largest study on heart failure amongst these ethnic groups. Full data collection started in September 2006 and will be completed by August 2009.Discussion: The E-ECHOES study will enable the planning and delivery of clinically and cost-effective treatment of this common and debilitating condition within these communities. In addition it will increase knowledge of the aetiology and management of heart failure within minority ethnic communities

Contribution of NOTCH1 genetic variants to bicuspid aortic valve and other congenital lesions

INTRODUCTION: Bicuspid aortic valve (BAV) affects 1% of the general population. NOTCH1 was the first gene associated with BAV. The proportion of familial and sporadic BAV disease attributed to NOTCH1 mutations has not been estimated. AIM: The aim of our study was to provide an estimate of familial and sporadic BAV disease attributable to NOTCH1 mutations. METHODS: The population of our study consisted of participants of the University of Leicester Bicuspid aoRtic vAlVe gEnetic research-8 pedigrees with multiple affected family members and 381 sporadic patients. All subjects underwent NOTCH1 sequencing. A systematic literature search was performed in the NCBI PubMed database to identify publications reporting NOTCH1 sequencing in context of congenital heart disease. RESULTS: NOTCH1 sequencing in 36 subjects from 8 pedigrees identified one variant c.873C>G/p.Tyr291* meeting the American College of Medical Genetics and Genomics criteria for pathogenicity. No pathogenic or likely pathogenic NOTCH1 variants were identified in 381 sporadic patients. Literature review identified 64 relevant publication reporting NOTCH1 sequencing in 528 pedigrees and 9449 sporadic subjects. After excluding families with syndromic disease pathogenic and likely pathogenic NOTCH1 variants were detected in 9/435 (2.1%; 95% CI: 0.7% to 3.4%) of pedigrees and between 0.05% (95% CI: 0.005% to 0.10%) and 0.08% (95% CI: 0.02% to 0.13%) of sporadic patients. Incomplete penetrance of definitely pathogenic NOTCH1 mutations was observed in almost half of reported pedigrees. CONCLUSIONS: Pathogenic and likely pathogenic NOTCH1 genetic variants explain 2% of familial and <0.1% of sporadic BAV disease and are more likely to associate with tetralogy of Fallot and hypoplastic left heart

Post-Implantation Inflammatory Responses to Xenogeneic Tissue-Engineered Cartilage Implanted in Rabbit Trachea: The Role of Cultured Chondrocytes in the Modification of Inflammation

Immune responses to tissue-engineered grafts made of xenogeneic materials remain poorly studied. The scope of current investigations is limited by the lack of information on orthotopically implanted grafts. A deeper understanding of these processes is of great importance since innovative surgical approaches include the implantation of xenogeneic decellularized scaffolds seeded by cells. The purpose of our work is to study the immunological features of tracheal repair during the implantation of tissue-engineered constructs based on human xenogeneic scaffolds modified via laser radiation in rabbits. The samples were stained with hematoxylin and Safranin O, and they were immunostained with antibodies against tryptase, collagen II, vimentin, and CD34. Immunological and inflammatory responses were studied by counting immune cells and evaluating blood vessels and collagen. Leukocyte-based inflammation prevailed during the implantation of decellularized unseeded scaffolds; meanwhile, plasma cells were significantly more abundant in tissue-engineered constructs. Mast cells were insignificantly more abundant in tissue-engineered construct samples. Conclusions: The seeding of decellularized xenogeneic cartilage with chondrocytes resulted in a change in immunological reactions upon implantation, and it was associated with plasma cell infiltration. Tissue-engineered grafts widely differed in design, including the type of used cells. The question of immunological response depending on the tissue-engineered graft composition requires further investigation