Silver-spoon upbringing improves early-life fitness but promotes reproductive ageing in a wild bird

Early-life conditions can have long-lasting effects and organisms that experience a poor start in life are often expected to age at a faster rate. Alternatively, individuals raised in high-quality environments can overinvest in early-reproduction resulting in rapid ageing. Here we use a long-term experimental manipulation of early-life conditions in a natural population of collared flycatchers (Ficedula albicollis), to show that females raised in a low-competition environment (artificially reduced broods) have higher early-life reproduction but lower late-life reproduction than females raised in high-competition environment (artificially increased broods). Reproductive success of high-competition females peaked in late-life, when low-competition females were already in steep reproductive decline and suffered from a higher mortality rate. Our results demonstrate that ‘silver-spoon’ natal conditions increase female early-life performance at the cost of faster reproductive ageing and increased late-life mortality. These findings demonstrate experimentally that natal environment shapes individual variation in reproductive and actuarial ageing in nature

A novel role of Drosophila cytochrome P450-4e3 in permethrin insecticide tolerance

The exposure of insects to xenobiotics, such as insecticides, triggers a complex defence response necessary for survival. This response includes the induction of genes that encode key Cytochrome P450 monooxygenase detoxification enzymes. Drosophila melanogaster Malpighian (renal) tubules are critical organs in the detoxification and elimination of these foreign compounds, so the tubule response induced by dietary exposure to the insecticide permethrin was examined. We found that expression of the gene encoding Cytochrome P450-4e3 (Cyp4e3) is significantly up-regulated by Drosophila fed on permethrin and that manipulation of Cyp4e3 levels, specifically in the principal cells of the Malpighian tubules, impacts significantly on the survival of permethrin-fed flies. Both dietary exposure to permethrin and Cyp4e3 knockdown cause a significant elevation of oxidative stress-associated markers in the tubules, including H2O2 and lipid peroxidation byproduct, HNE (4-hydroxynonenal). Thus, Cyp4e3 may play an important role in regulating H2O2 levels in the endoplasmic reticulum (ER) where it resides, and its absence triggers a JAK/STAT and NF-κB-mediated stress response, similar to that observed in cells under ER stress. This work increases our understanding of the molecular mechanisms of insecticide detoxification and provides further evidence of the oxidative stress responses induced by permethrin metabolism

The Persistence of Earnings and Corporate Governance in IPO Firms

In this study, we investigate the earnings persistence in IPO firms by examining the two components of earnings: accruals and cash flows. We also analyze the impact of corporate governance on earnings and the two earnings components. In our comparison of the top and bottom quartiles based on the firms\u27 earnings at the IPO year, we find that although the top quartile firms have a significantly positive accrual component in the IPO year, they eventually have the same negative accrual component of earnings as the bottom quartile firms in the second year after the IPO. In contrast, we find that the significant difference in the cash flow component between the top and bottom quartiles persists during the two years after the IPO. This finding supports the existing literature that the cash flow component contributes to the persistence of earnings while the accrual component does not. We also find that the corporate governance structure has a significant impact on earnings and the components of earnings for the top quartile firms, but not for the bottom quartile firms. This is particularly evident since the top quartile firms have the opportunity to manage their earnings, while firms in the lowest quartile are unable to manage their earnings

Dietary Supplement Labeling: Cognitive Biases, Market Manipulation & Consumer Choice

There exists increasing concern that the Dietary Supplements Health and Education Act (DSHEA) has proven ineffective. Much of the concern regards the disparity in legislative treatment between dietary supplements, foods, and pharmaceutical drugs. Namely, while pharmaceutical drugs must undergo years of costly pre-market testing, most supplements, like foods, can immediately enter the market, and only after repeated instances of adverse reactions can the Food and Drug Administration (FDA) remove them. Such a framework appears to belie both consumer expectations and marketing strategies, as supplements tend to be most perceived for their apparent medicinal qualities. This philosophy of waiting for a foreseeable harm also strikes many as unnecessary, inefficient, and immoral. On the other hand, most supplements have proven safe and either benign or reasonably effective. Moreover, before policy-makers mandate extensive pre-market testing of all supplements, consider the likely effect on production: a certain percentage of supplement makers will find the economics of production too costly and will thus leave the market. Granted, foreign markets for supplements might still provide the requisite incentives for production, but a more costly entrance fee into the U.S. market would clearly deter some level of production and convince a number of makers to leave the market altogether. Equally troubling, companies which choose to remain in the market would presumably pass on a portion of the increased costs to consumers, who often bear the costs of heightened regulation. Consequently, many beneficial supplements would be priced out of the reach of consumers who either have become users of those products or could become users. The issue then is one of nuance. Rather than sweeping regulatory intervention, perhaps more carefully-tailored alterations would prove most desirable. This philosophy appears desirable given informational deficiencies among dietary supplement consumers, particularly those with exploitable cognitive biases. Promisingly, such deficiencies may be ameliorated through low-cost measures that promote enhanced communication of product characteristics. For these reasons, this Article proposes a refined approach to dietary supplement labeling that would legally distinguish them on the basis of potential risk and anticipated benefit. Indeed, the existing legal construct of the phrase dietary supplements is both curious and overly simplistic. It includes minerals, vitamins, herbs, botanical extracts, and amino acids - items that are not only functionally different, but which present radically different risks and benefits. Along those lines, the very consumers of supplements should be more carefully distinguished. How might such a revised communicatory model work without precipitating material price increases or deterring beneficial production? One method would entail more carefully-contemplated labeling requirements. Such requirements should enhance consumer risk-assessment and reward reputable supplement manufacturers. To accomplish these goals, labels should reveal potential interactions with pharmaceutical drugs and other supplements, warnings of over-usage, predictable distinctions between health claims and structure/function claims, and a recommended intake range based on age and gender, among other personal characteristics. Of similar benefit would be assured ingredient content, as well as greater coordination between the FDA and the Federal Trade Commission (FTC) in regulating false or misleading supplement claims. Importantly, because such labeling requirements would impose only minimal cost increases to manufacturers

Earnings quality in ex-post failed firms.

This paper analyses earnings quality in ex-post failed firms. Using a large sample of UK bankrupt firms, we find that failed firms manage earnings upwards in the four years prior to failure. This manipulation is achieved in two ways: (1) through accounting (accruals) manipulation; and (2) by implementing real operating actions that deviate from normal practice. We show that these two types of manipulation lead to reduced earnings reliability. We use conditional conservatism as a proxy for reliability, as prior literature links conditional accounting conservatism to better governance and positive economic outcomes. Our results show that conditional conservatism decreases substantially in the years prior to failure. Finally, we show that accruals manipulation is more pronounced in ex-post bankrupt firms with low ex-ante probability of failure, and that ex-post bankrupt firms with high ex-ante failure probability, having likely exhausted the opportunities for accrual manipulation, manipulate real operations more aggressivelyFirm failure; Accruals management; Real earnings management; Conditional conservatism; Earnings quality; Bankruptcy;

Spectroscopy of a synthetic trapped ion qubit

$^{133}\text{Ba}^+$ has been identified as an attractive ion for quantum information processing due to the unique combination of its spin-1/2 nucleus and visible wavelength electronic transitions. Using a microgram source of radioactive material, we trap and laser-cool the synthetic $A$ = 133 radioisotope of barium II in a radio-frequency ion trap. Using the same, single trapped atom, we measure the isotope shifts and hyperfine structure of the $6^2 \text{P}_{1/2}$ $\leftrightarrow$ $6^2 \text{S}_{1/2}$ and $6^2 \text{P}_{1/2}$ $\leftrightarrow$ $5^2 \text{D}_{3/2}$ electronic transitions that are needed for laser cooling, state preparation, and state detection of the clock-state hyperfine and optical qubits. We also report the $6^2 \text{P}_{1/2}$ $\leftrightarrow$ $5^2 \text{D}_{3/2}$ electronic transition isotope shift for the rare $A$ = 130 and 132 barium nuclides, completing the spectroscopic characterization necessary for laser cooling all long-lived barium II isotopes