Dollar Cost Averaging - The Role of Cognitive Error

Dollar Cost Averaging (DCA) has been shown to be mean-variance inefficient, yet it remains a very popular strategy. Recent research has attempted to explain its popularity by assuming more complex risk preferences. This paper rejects such explanations by demonstrating that DCA is sub-optimal regardless of preferences over terminal wealth. Instead, this paper identifies the cognitive error in the argument that is normally put forward in favor of the strategy. This gives us a simpler explanation for DCA’s continued popularity: That investors are making a mistake (a misleading comparison) when assessing the benefits of DCA. Unlike previous explanations, this suggests that using DCA may be detrimental to investors

Diversification returns, rebalancing returns and volatility pumping

There is now a substantial literature on the effects of rebalancing on portfolio performance. It is widely argued in the theoretical literature that rebalanced strategies are inherently likely to generate greater terminal wealth than unrebalanced strategies, although empirical studies do not generally support this claim. We show that this claim is based on a misattribution between ‘rebalancing returns’ which are specific to the act of rebalancing, and ‘diversification returns’ which can be earned by both rebalanced and unrebalanced strategies. Confusion appears to have increased because in some situations these two distinct effects have the same magnitude. This issue has important implications for return attribution in diversified portfolios. Misleading claims about the benefits of rebalancing are likely to lead investors into strategies which involve insufficient diversification and excessive transactions costs

Nanoparticle Design and Novel Approaches to Enhance Photothermal Cancer Therapy.

Rapid advances in bioinformatics and nanotechnology have sparked pre-clinical development of innovative therapies with potential to transform approaches to non-specific clinical practices such as chemotherapy and radiation. One of few nanoparticle-based treatments in clinical trials is photothermal therapy (PTT), which is localized by near infrared light activation of heat-producing gold nanoshells. Here we demonstrate nanoparticle-mediated PTT as a multifunctional platform to address key challenges of cancer medicine, to improve patient tolerance and long-term survival. We present our work in two sections: enhancing efficacy in metastatic settings, and increasing specificity to reduce associated toxicity. In the first section, we focus on the efficacy of PTT against breast cancer stem cells (BCSCs) and tumor-mediated immunosuppressive signaling – vital drivers of cancer growth and metastasis. First we study PTT via highly crystallized iron oxide nanoparticles (HCIONPs) in human breast cancer cells in immune-compromised mice. PTT inhibits both epithelial-like (ALDH+) and mesenchymal-like (CD44+/CD24-) BCSCs and BCSC-driven secondary tumor formation. PTT prior to surgery prevents lymph node metastasis. Next we evaluate HCIONP-mediated PTT and cancer immunotherapy (PD-L1 antibody) in immune-competent mice. PTT significantly reduces mouse ALDH+ BCSCs when given alone and in combination with PD-L1 antibody. Combination treatment reveals promising reductions in tumor growth and formation of lung macrometastases. Furthermore, increases of key inflammatory cytokines and immune cell-attracting chemokines suggest the potential to enhance T-cell tumor infiltration to trigger a systemic, cancer (stem) cell-specific immune response. In the second section, we focus on development of optimized targeted nanoparticle formulations, applicable for PTT, to improve specificity and efficiency of cancer therapy. First we report a new technique – ‘living’ PEGylation – to control the density and composition of heterobifunctional poly(ethylene glycol) (HS-PEG-R) on gold nanoparticles. Applications we demonstrate include control of targeting ligand (HS-PEG-RGD) density to maximize nanoparticle targeting efficiency, and development of double-charged, stealthy nanoparticles (optimal HS-PEG-NH2:HS-PEG-COOH ratio) to minimize immune cell uptake. Lastly, we describe targeted, theranostic nanocomposites with a core-satellite structure for PTT and magnetic resonance imaging. A facilely produced “clickable” targeting peptide enables precise control over attachment to the nanoparticles to prevent steric hindrance and optimize binding to the target receptor.PhDPharmaceutical SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/116764/1/hpaholak_1.pd

Surface-modified minerals for radionuclide sequestration

This thesis is concerned with experiments designed to identify materials to increase the utility of the Sellafield Ion Exchange Plant (SIXEP) process. Clinoptilolite, ZSM-5, vermiculite and kaolinite have been surface modified by grafting with APTES, TMSPE and TMSPETT ligands using varying grafting times (1-24 h), ligand concentrations (1-3 mmol) and solvents with different polarities (with dielectric constant between 1.9 80). Materials before and after grafting were analysed using long and short range techniques including elemental analysis (CHN), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), solid state nuclear magnetic resonance (SSNMR) and infra-red (FTIR) spectroscopy. The amount of graft placed on the surface increased with reaction time for all materials as the amount of carbon per unit mass of the support, determined by CHN analysis, increased with time. C-H stretches were consistently observed in the FTIR of the grafted materials but no change was observed to the long range order in the PXRD pattern. 13C SSNMR showed that small solvent molecules such as acetone can become trapped in the material supports during grafting and long drying times are required to ensure that trapped solvent molecules do not contaminate the CHN analyses of the materials after grafting. Clinoptilolite and vermiculite consistently achieved higher grafting levels than ZSM-5 or kaolinite, with clinoptilolite (NDA) showing the greatest carbon content of 56.16 mmol of APTES per gram of clinoptilolite using hexane as the solvent. Despite a similar molecular weight, TMSPE consistently showed lower levels of grafting than APTES. APTES grafting levels were increased by using citric, phosphoric and nitric acid (1-3 mol L-1) to pre-treat the surface of the materials over different time periods (1-24 h) to improve the level of APTES graft. While the carbon content was higher for acid treated clinoptilolite (NDA) after grafting, in the case of the citric acid treatment, this increase maybe due to the formation of iron (III) citrate from the dissolution of poorly crystalline iron impurities in the clinoptilolite (NDA). Ungrafted and grafted clinoptilolite, ZSM-5, vermiculite and kaolinite samples were investigated for their ability to sequester caesium, strontium, uranium and plutonium species. Absorption/desorption experiments were initially conducted on the ungrafted compounds using caesium and strontium cations to establish a baseline for the most abundant species in pond liquor. Caesium and strontium cations are trapped within the cages of clinoptilolite in an ion exchange reaction which places these ions on sites of the appropriate size and geometry for these species. Once ion exchanged, neither ion is desorbed from the clinoptilolite readily and they remain trapped inside the cage, irrespective of concentration of other species in solution. While vermiculite is also successful at removing both caesium and strontium cations, it is less successful in retaining them during desorption, with typically one third of the trapped ions being released back into solution. ZSM-5 and kaolinite have contrasting behaviour, due to few exchangeable cations, meaning caesium and strontium uptake is poor. Samples of clinoptilolite with different particle sizes and potassium content were compared and showed that smaller particles facilitated faster exchange. Grafting had a variable effect on the caesium/strontium cation uptake and release during absorption/desorption presumably as a result of the donors on grafted ligand interacting weakly with the large cations. Experiments using distilled water and synthetic liquor (carbonated sodium hydroxide), demonstrated uranium and plutonium species were extracted by all materials after grafting at concentrations in the SIXEP range. The most successful ligand/graft combination for plutonium at pH 7 was APTES grafted on clinoptilolite (10.79% carbon)

What do retail FX traders learn?

What is the benefit of experience? Using data from a leading trading platform we find no evidence that retail FX traders learn to trade better, but they do appear to learn about their innate abilities as traders and respond appropriately. In particular, following an unsuccessful trading day, they are more likely to cease trading, to trade smaller amounts and to trade less frequently. These effects are stronger for younger and less experienced traders who might be expected to have more to learn than older, more experienced traders. As regards learning through experience, surprisingly we find that more seasoned traders demonstrate a slight decline in performance once we account for the endogenous decision to cease trading, and even very experienced traders consistently lose money

Market and Style Timing: German Equity and Bond Funds

We apply parametric and non-parametric estimates to test market and style timing ability of individual German equity and bond mutual funds using a sample of over 500 equity and 350 bond funds, over the period 1990-2009. For equity funds, both approaches indicate no successful market timers in the 1990-1999 or 2000-2009 periods, but in 2000-2009 the non-parametric approach gives fewer unsuccessful market timers than the parametric approach. There is evidence of successful style timing using the parametric approach, and unsuccessful style timing, particularly in the 2000-2009 period. There is evidence of positive and negative bond timing in the 2000-09 period

The Genetics of Language Acquisition

This chapter focuses on the understanding of the role of genetics in language and explores how genetics contribute to language, and shows how new genetic techniques can offer inroads into the molecular basis of language acquisition. It discusses some of the key findings of gene x environment studies and provides a snapshot of the understanding in the field, considering some of the limitations of the type of study design. The chapter describes the field of play in the genetics of language acquisition and explains the heritability of language and the role of family and twin studies in the understanding of language. It also explores the inheritance mechanisms that are implicated in language development. The chapter considers how modern DNA sequencing approaches are revolutionizing the field of language genetics. Heritability studies have provided many key insights into the genetics of both language acquisition and language disorders. Insights into mechanisms can also come from the opposite end of the language ability spectrum

Diabetes in athletes

This issue of eMedRef provides information to clinicians on the pathophysiology, diagnosis, and therapeutics of diabetes in athletes