Recession and the Employment of Demographic Groups

macroeconomics, Recession, Demographic

Les limites du discours économique sur la publicité

It is often assumed that the negative impact of advertising is the basis from which economic studies in this area are to be undertaken. The authors state that the evidence supporting such a claim is far from obvious. In fact, the suggestion brought forth is that this assumption may be faulty. Specific areas of inquiry are suggested such as the cost of advertising in relation to marketing and manufacturing costs as well as the impact of advertising on GNP. The authors point out that from a demand analysis perspective, the eternal diseconomies in consumption due to advertising as claimed and condemned by economists, is really the result of the consumer's decision making process in the market place. The economists fail to take into account all of the social and psychological forces which impact on consumer behavior. Finally, the authors state that from a supply analysis orientation, no conclusion link has been found between advertising, industrial concentration and market power

Shrinkage Estimators in Online Experiments

We develop and analyze empirical Bayes Stein-type estimators for use in the estimation of causal effects in large-scale online experiments. While online experiments are generally thought to be distinguished by their large sample size, we focus on the multiplicity of treatment groups. The typical analysis practice is to use simple differences-in-means (perhaps with covariate adjustment) as if all treatment arms were independent. In this work we develop consistent, small bias, shrinkage estimators for this setting. In addition to achieving lower mean squared error these estimators retain important frequentist properties such as coverage under most reasonable scenarios. Modern sequential methods of experimentation and optimization such as multi-armed bandit optimization (where treatment allocations adapt over time to prior responses) benefit from the use of our shrinkage estimators. Exploration under empirical Bayes focuses more efficiently on near-optimal arms, improving the resulting decisions made under uncertainty. We demonstrate these properties by examining seventeen large-scale experiments conducted on Facebook from April to June 2017

Les limites du discours économique sur la publicité

It is often assumed that the negative impact of advertising is the basis from which economic studies in this area are to be undertaken. The authors state that the evidence supporting such a claim is far from obvious. In fact, the suggestion brought forth is that this assumption may be faulty. Specific areas of inquiry are suggested such as the cost of advertising in relation to marketing and manufacturing costs as well as the impact of advertising on GNP. The authors point out that from a demand analysis perspective, the eternal diseconomies in consumption due to advertising as claimed and condemned by economists, is really the result of the consumer's decision making process in the market place. The economists fail to take into account all of the social and psychological forces which impact on consumer behavior. Finally, the authors state that from a supply analysis orientation, no conclusion link has been found between advertising, industrial concentration and market power.

Cells in Space

Discussions and presentations addressed three aspects of cell research in space: the suitability of the cell as a subject in microgravity experiments, the requirements for generic flight hardware to support cell research, and the potential for collaboration between academia, industry, and government to develop these studies in space. Synopses are given for the presentations and follow-on discussions at the conference and papers are presented from which the presentations were based. An Executive Summary outlines the recommendations and conclusions generated at the conference

Early phrenic motor neuron loss and transient respiratory abnormalities following unilateral cervical spinal cord contusion

Contusion-type cervical spinal cord injury (SCI) is one of the most common forms of SCI observed in patients. In particular, injuries targeting the C3-C5 region affect the pool of phrenic motor neurons (PhMNs) that innervates the diaphragm, resulting in significant and often chronic respiratory dysfunction. Using a previously described rat model of unilateral midcervical C4 contusion with the Infinite Horizon Impactor, we have characterized the early time course of PhMN degeneration and consequent respiratory deficits following injury, as this knowledge is important for designing relevant treatment strategies targeting protection and plasticity of PhMN circuitry. PhMN loss (48% of the ipsilateral pool) occurred almost entirely during the first 24 h post-injury, resulting in persistent phrenic nerve axonal degeneration and denervation at the diaphragm neuromuscular junction (NMJ). Reduced diaphragm compound muscle action potential amplitudes following phrenic nerve stimulation were observed as early as the first day post-injury (30% of pre-injury maximum amplitude), with slow functional improvement over time that was associated with partial reinnervation at the diaphragm NMJ. Consistent with ipsilateral diaphragmatic compromise, the injury resulted in rapid, yet only transient, changes in overall ventilatory parameters measured via whole-body plethysmography, including increased respiratory rate, decreased tidal volume, and decreased peak inspiratory flow. Despite significant ipsilateral PhMN loss, the respiratory system has the capacity to quickly compensate for partially impaired hemidiaphragm function, suggesting that C4 hemicontusion in rats is a model of SCI that manifests subacute respiratory abnormalities. Collectively, these findings demonstrate significant and persistent diaphragm compromise in a clinically relevant model of midcervical contusion SCI; however, the therapeutic window for PhMN protection is restricted to early time points post-injury. On the contrary, preventing loss of innervation by PhMNs and/or inducing plasticity in spared PhMN axons at the diaphragm NMJ are relevant long-term targets

Quantitative Effects of Iron Chelators on Hydroxyl Radical Production by the Superoxide-Driven Fenton Raction

Iron bound to certain chelators is known to promote the conversion of superoxide radicals (O2) to hydroxyl radicals (HO\u27) by the superoxide-driven Fenton reaction. The production of HO\u27 by various iron chelates was studied using the reaction of dimethyl sulfoxide and HO\u27 to produce methane sulphinic acid. Methane sulphinic acid was quantified by use of a simple colorimetric assay and used to determine the amounts of HO\u27 produced. Superoxide was generated from 200 M hypoxanthine and 0.05 U/ml xanthine oxidase in the presence of 0-100 M iron and 100 M of each chelator. The results of this preliminary investigation illustrate that, at physiological pH, the superoxide-driven Fenton reaction is significantly promoted by iron chelated to EDTA, nitrilotriacetate, and citrate, but is not promoted by the other anions studied