What moves sovereign bond markets? The effects of economic news on U.S. and German yields

Economic announcements are an important source of information, containing news that spills over internationally across markets, affecting yields. An analysis of the U.S. and German sovereign bond markets finds that the largest moves in yields are associated with U.S. announcements on labor market conditions, real GDP growth, and consumer sentiment.Bond market ; Bond market - Germany ; International finance

Neighborhood Competition in an Old‐Field Plant Community

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/119099/1/ecy19876851211.pd

POLY (AMIDO AMINE) DENDRIMERS: TRANSEPITHELIAL TRANSPORT MECHANISMS AND APPLICATIONS IN ORAL DRUG DELIVERY

Small molecule chemotherapy drugs used in clinical practice are plagued by dose-limiting side effects due to off-target toxicities. In addition, because of their low water solubility and poor bioavailability, they must be administered intravenously, leading to high treatment costs and recurring hospital visits. There is a significant need for therapies that improve the bioavailability of chemotherapy agents and enhance specific drug release in the tumor environment. Dendrimers, a class of highly-branched, nanoscale polymers, share many characteristics with traditional polymeric carriers, including water solubility, high capacity of drug loading and improved biodistribution. Poly (amido amine) (PAMAM) dendrimers have shown promise as oral drug carriers due to their compact size, high surface charge density and permeation across the intestinal epithelial barrier. Attachment of chemotherapy drugs to PAMAM dendrimers has the potential to make them orally administrable and reduce off-target toxicities. In this dissertation we investigate the transport mechanisms of PAMAM dendrimers and their potential in oral drug delivery. We demonstrate that anionic G3.5 dendrimers are endocytosed by dynamin-dependent mechanisms and their transport is governed by clathrin-mediated pathways. We show that dendrimer cellular internalization may be a requisite step for tight junction opening. We also demonstrate that conjugation of small poly (ethylene glycol) chains to anionic dendrimers decreases their transport and tight junction opening due to reduction in surface charge, illustrating that small changes in surface chemistry can significantly impact transepithelial transport. Knowledge of transport mechanisms and the impact of surface chemistry will aid in rational design of dendrimer oral drug delivery systems. The potential of dendrimers as oral drug delivery carriers is demonstrated by the evaluation of G3.5 PAMAM dendrimer-SN38 conjugates for oral therapy of hepatic colorectal cancer metastases, a pathology present in over 50% of colorectal cancer cases that is responsible for two-thirds of deaths. Conjugation of SN38, a potent chemotherapy drug with poor solubility and low bioavailability, to PAMAM dendrimers via a glycine linker increased intestinal permeability, decreased intestinal toxicity and showed selective release in the presence of liver carboxylesterase, illustrating that PAMAM dendrimers have the potential to improve the oral bioavailability of potent anti-cancer therapeutics

Attenuation of the Ganglion Cell Layer in a Premature Infant Revealed with Handheld Spectral Domain Optical Coherence Tomography

Purpose: To report on subclinical retinal abnormalities shown through handheld spectral domain optical coherence tomography on a premature infant. Methods: Case report. Results: The initial and follow-up exams on a premature infant revealed severely attenuated ganglion cell and nerve fiber layers. There was cystoid macular edema in both eyes at the initial visits, which resolved by the 1-year follow-up. Discussion: Optical coherence tomography can reveal significant retinal abnormalities in premature infants which are not detectable through funduscopic exam. Documenting such findings may be useful for the comprehensive management of vision problems in children with a history of premature birth

Comparative Risk Assessment in New York

Comparative risk assessment (CRA) is the examination of the relative risks posed by different dangers, with a view to deciding which dangers deserve the most governmental attention. CRA frequently tries to reduce different problems to a common metric, usually the statistical lives saved by a program, so that apples can be weighed against oranges. This article will discuss and assess the growing use of CRA in New York State. There are two principal arguments for the use of CRA in the environmental context. The first is that we do not have unlimited resources; we cannot move against all problems simultaneously. We must set priorities among environmental programs, and attack the biggest problems first, in a kind of triage. The second argument is that a rational, quantitative approach should be applied to environmental problems so that we can rigorously analyze them, relying more on science and less on politics and public prejudices

Distinguishing the roles of dispersal in diversity maintenance and in diversity limitation

In recent years, a considerable research effort has gone into studying how dispersal might affect the diversity of local communities. While this general topic has received attention from theoretical and empirical ecologists alike, the research focus has differed between the two groups; theoretical ecologists have explored the role of dispersal in the maintenance of diversity within local communities, whereas empirical ecologists have sought to quantify the role of dispersal in limiting local diversity. In this paper we argue that, because the underlying causal relationship between dispersal and diversity is empirically unknown (e.g., flat, linear, and humped relationships have been suggested), there is no necessary relationship between the dispersal-maintained and the dispersal-limited component of diversity. In order to test and parameterize theoretical models we therefore need to develop a empirical approaches that allow us to quantify not only the dispersal-limited but also the dispersal-maintained component of diversity

Litter drives ecosystem and plant community changes in cattail invasion

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116913/1/eap2009192398.pd

Quantifying individual- and community-level effects of competition using experimentally-determined null species pools

The effects of competition on individual fitness and species diversity were investigated in a first-year old field by comparing the natural community to an experimentally-determined null community. The species pool for the null community was estimated from low-density plots, and hypothetical sample plots in the null community were constructed by random sampling from the species pool. Individual plants were larger in low-density plots than control plots, indicating that competition reduced individual fitness. Competition appeared to reduce diversity in half the plots (i.e. species richness and diversity were lower than in hypothetical null community plots with the same number of individuals), but did not affect diversity in the other plots. However, the reduction in diversity could be explained as an artifact caused by spatial aggregation in control plots. The magnitude of the effects of competition on diversity did not change with plot density, and no species consistently increased or decreased in relative abundance as plot density increased. We conclude that competition had no effect on diversity in this community, despite the strong effect on individual growth.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73205/1/3236636.pd