Letter from E. C. and Mrs. E. C. Garman to Emma P. Larimore

Letter from E. C. and Mrs. E. C. Garman to Emma P. Larimore. The one-page typewritten letter is dated 20 November 1912

Anadromous fish as marine nutrient vectors

The tidal freshwater of Virginia supports anadromous herring (Alosa spp.) spawning runs in the spring; however, their importance as nutrient delivery vectors to the freshwater fish food web remains unknown. The stable isotope signatures of fishes from 21 species and four different guilds (predators, carnivores, generalists, and planktivores) were examined in this study to test the hypothesis that marine derived nutrients (MDNs) brought by anadromous fish would be traced into the guilds that incorporated them. Spawning anadromous fish were 13C and 34S-enriched (δ13C and δ34S of approximately 18‰ and 17.7‰, respectively) relative to resident freshwater fish. Of the guilds examined, only predators showed 13C and 34S-enrichment similar to the anadromous fish; however, some generalist catfish also showed enriched signatures. Specific fatty acid δ13C signatures for gizzard shad (Dorosoma cepedianum), blue catfish (Ictalurus furcatus), and alewife (Alosa pseudoharengus), show a 10‰ range among fishes, clearly reflecting isotopically distinct dietary sources. The δ13C and δ34S distribution and range among the freshwater fishes suggest that both autochthonous and allochthonous (terrestrial C3 photosynthetic production and MDN) nutrient sources are important to the tidal freshwater fish community

Book Review: Archaeology and Created Memory: Public History in a National Park by Paul A. Shackel

Book Review: Archaeology and Created Memory: Public History in a National Park by Paul A. Shackel, 2000, Kluwer/Plenum Academic Publishers, New York, 210 pages, $57.50 (hardcover)

Letter from E. C. Garman to B. R. Colson

Letter from E. C. Garman to B. R. Colson. The one-page typewritten note is on E. C. Garman & Son letterhead and dated 25 November 1912

COVID-19: Turning a Pandemic into a Learning Opportunity for Senior Medical Students

Normally, the 4th year of medical school in the United States is when students narrow down their clinical experiences to reflect their interests, and prepare for applying to residency programs. The COVID-19 pandemic has made this process difficult, forcing many senior students from the frontlines to the sidelines. Policy changes have forbidden students from attending some in-person rotations and participating in operational procedures. The impact that COVID-19 has had on medical curricula varies between institutions, with many being hindered significantly by the event. However, my institution is using novel approaches to patient care, allowing senior students to help. Senior students are using telecommunication to connect with patients and assist them with their medical questions and needs. They are acting as Transitional Care Providers and Patient Navigation Assistants, allowing them to use their knowledge and skills to help both the patients and the healthcare system. Other students are acting as “COVID-19 case-trackers,” attempting to mitigate the spread of infections. By allowing students to take on these roles during the pandemic, institutions like mine are making this time one of valuable experience and learning. For some senior medical students, the COVID-19 pandemic, with all of its hardships, has become an invaluable learning opportunity and a chance to serve their community

Genetic differentiation of spring-spawning and fall-spawning male Atlantic sturgeon in the James River, Virginia

Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations are currently at severely depleted levels due to historic overfishing, habitat loss, and pollution. The importance of biologically correct stock structure for effective conservation and management efforts is well known. Recent improvements in our understanding of Atlantic sturgeon migrations, movement, and the occurrence of putative dual spawning groups leads to questions regarding the true stock structure of this endangered species. In the James River, VA specifically, captures of spawning Atlantic sturgeon and accompanying telemetry data suggest there are two discrete spawning groups of Atlantic sturgeon. The two putative spawning groups were genetically evaluated using a powerful microsatellite marker suite to determine if they are genetically distinct. Specifically, this study evaluates the genetic structure, characterizes the genetic diversity, estimates effective population size, and measures inbreeding of Atlantic sturgeon in the James River. The results indicate that fall and spring spawning James River Atlantic sturgeon groups are genetically distinct (overall FST = 0.048, F’ST = 0.181) with little admixture between the groups. The observed levels of genetic diversity and effective population sizes along with the lack of detected inbreeding all indicated that the James River has two genetically healthy populations of Atlantic sturgeon. The study also demonstrates that samples from adult Atlantic sturgeon, with proper sample selection criteria, can be informative when creating reference population databases. The presence of two genetically-distinct spawning groups of Atlantic sturgeon within the James River raises concerns about the current genetic assignment used by managers. Other nearby rivers may also have dual spawning groups that either are not accounted for or are pooled in reference databases. Our results represent the second documentation of genetically distinct dual spawning groups of Atlantic sturgeon in river systems along the U.S. Atlantic coast, suggesting that current reference population database should be updated to incorporate both new samples and our increased understanding of Atlantic sturgeon life history

Theoretical Sensitivity Analysis for Quantitative Operational Risk Management

We study the asymptotic behavior of the difference between the values at risk VaR(L) and VaR(L+S) for heavy tailed random variables L and S for application in sensitivity analysis of quantitative operational risk management within the framework of the advanced measurement approach of Basel II (and III). Here L describes the loss amount of the present risk profile and S describes the loss amount caused by an additional loss factor. We obtain different types of results according to the relative magnitudes of the thicknesses of the tails of L and S. In particular, if the tail of S is sufficiently thinner than the tail of L, then the difference between prior and posterior risk amounts VaR(L+S) - VaR(L) is asymptotically equivalent to the expectation (expected loss) of S.Comment: 21 pages, 1 figure, 4 tables, forthcoming in International Journal of Theoretical and Applied Finance (IJTAF

Person-to-Person Lending: The Pursuit of (More) Competitive Credit Markets

Person-to-person lending (P2PL) on the Internet is a relatively new credit market. The success of these markets hinges on their ability to provide both borrowers and lenders the chance to improve on the opportunities available in traditional intermediated credit markets. In essence, P2PL must create a more competitive market. Empirical observations provide evidence that frictions exist in these markets, which generally move markets away from competitive outcomes. Currently, auctions are the most popular mechanism for P2PL. This paper develops and analyzes an equilibrium competing auction model of P2PL. Coordination frictions and the presence of non-creditworthy borrowers create an environment where many potentially productive transactions are not made and interest rate dispersion is observed. Additionally, if the market naturally segments into groups of similar borrowers then increased frictions in a segment may lead some portion of lenders to migrate to a different segment

Cash transfers and the mental health of young people: evidence from South Africa's child support grant

This study examines the longitudinal impact of the South African Child Support Grant (CSG) on risk for depression and life satisfaction among young people (15–19 years). We analysed data from the last three waves of the National Income Dynamics Study (NIDS), a nationally representative panel survey that took place every two years from 2008 to 2017. We used an instrumental variable (IV) approach that exploits multiple changes in age eligibility from 1998 to 2012. Depressive symptoms were assessed using an 8-item version of the Centre for Epidemiological Studies Depression Scale; participants who scored above 8 were considered at risk for depression. Life satisfaction was rated on a scale of 1 (‘very dissatisfied’) to 10 (‘very satisfied’); participants who scored 8 or above were classified as satisfied. We also examined impacts on educational deficit (≥2 years behind) and not being in education, employment or training (NEET) as secondary outcomes, as these are also important for mental health. Age eligibility strongly predicted CSG receipt at Wave 3. In instrumental variable models, CSG receipt did not influence the risk for depression (β = 0.10, SE = 0.10, p = 0.316), nor life satisfaction (β = −0.07, SE = 0.09, p = 0.420) at Wave 3, nor at Waves 4 or 5. Some improvements in educational deficit were observed at Wave 3 among CSG beneficiaries compared to non-beneficiaries. These results were robust to multiple specifications. CSG receipt did not improve the psychological wellbeing of adolescents and young adults, nor did it improve their education or employment outcomes. Our findings highlight the need to identify alternative social policies that address the root causes of youth social disadvantage, in conjunction with targeted approaches to improve the mental health of young South Africans living in poverty