Cassettes for PCR-mediated gene tagging in Candida albicans utilizing nourseothricin resistance

addresses: Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.types: Journal Article; Research Support, Non-U.S. Gov't; Validation StudiesThis is the author's post-print version of an article published in Yeast, 2011, Vol. 28, Issue 12, pp. 833 – 841 Copyright © Wiley-Blackwell 2011. The definitive version is available at www3.interscience.wiley.comIn recent years a number of molecular tools have been reported for use in the human fungal pathogen Candida albicans, including PCR-mediated approaches for gene disruption, conditional expression and epitope tagging. Traditionally these methods have utilized auxotrophic markers; however, the availability of auxotrophic markers can be limiting and in some instances their use may also impact on the interpretation of results. As a result, the use of positive selection markers has now become more commonplace. Here we report the development and validation of a set of cassettes for PCR-mediated gene tagging and overexpression studies utilizing the nourseothricin resistance (CaNAT1) positive selection marker. In particular we have produced cassettes containing yeast-enhanced GFP, YFP, CFP, RFP and a combined V5-6xHis epitope tag. The cassettes are engineered for use in PCR-mediated gene tagging strategies where insertion is targeted to the 3' end of the gene of interest. In addition, to facilitate protein functional analysis and genetic suppression studies through the use of overexpression, we have also constructed a promoter replacement cassette containing the ENO1 promoter which is known to be expressed at a high level. These cassettes expand on the range of molecular tools available for working with C. albicans and may also be used in other Candida species that display sensitivity to nourseothricin

Novel insights into host-fungal pathogen interactions derived from live-cell imaging

Acknowledgments The authors acknowledge funding from the Wellcome Trust (080088, 086827, 075470 and 099215) including a Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377 and FP7-2007–2013 grant agreement HEALTH-F2-2010-260338–ALLFUN to NARG.Peer reviewedPublisher PD

Platform Competition in the Autobidding World

We study the problem of auction design for advertising platforms that face strategic advertisers who are bidding across platforms. Each advertiser's goal is to maximize their total value or conversions while satisfying some constraint(s) across all the platforms they participates in. In this paper, we focus on advertisers with return-over-investment (henceforth, ROI) constraints, i.e. each advertiser is trying to maximize value while making sure that their ROI across all platforms is no less than some target value. An advertiser interacts with the platforms through autobidders -- for each platform, the advertiser strategically chooses a target ROI to report to the platform's autobidder, which in turn uses a uniform bid multiplier to bid on the advertiser's behalf on the queries owned by the given platform. Our main result is that for a platform trying to maximize revenue, competition with other platforms is a key factor to consider when designing their auction. While first-price auctions are optimal (for both revenue and welfare) in the absence of competition, this no longer holds true in multi-platform settings. We show that there exists a large class of advertiser valuations over queries such that, from the platform's perspective, running a second price auction dominates running a first price auction. Furthermore, our analysis reveals the key factors influencing platform choice of auction format: (i) intensity of competition among advertisers, (ii) sensitivity of bid landscapes to an auction change (driven by advertiser sensitivity to price changes), and (iii) relative inefficiency of second-price auctions compared to first-price auctions

Principio de capacidad contributiva

La presente tesis busca esclarecer el contenido y abordar el alcance del principio de capacidad contributiva. Así a partir de un análisis filosófico e histórico del principio de capacidad contributiva este trabajo analizará su naturaleza jurídica y posición en un ordenamiento jurídico. Posteriormente, y en base al análisis de ésta última interrogante, se analizará el rol que tiene el principio de capacidad contributiva, no sólo analizado desde una perspectiva individual, si no, que analizado como el principio jurídico material rector de un sistema tributario democrático. Analizada la historia y evolución del principio de capacidad contributiva, y conceptualizada su naturaleza como principio jurídico propiamente tal, se desarrollarán las bases y fundamentos que permitan sustentar una de las posiciones principales de este trabajo: la capacidad contributiva como principio jurídico constitucional. Argumentada dicha posición, se detallarán las múltiples definiciones del principio de capacidad contributiva, que se enmarcan en esta postura jurídico constitucional, permitiendo así, poder entender y definir de manera esquemática y conceptual, los elementos del principio de capacidad contributiva. A continuación, se analizará el fundamento del principio de capacidad contributiva, como un principio jurídico constitucional, que, dentro de sus facetas, opera como una garantía en favor de los contribuyentes. Dicho fundamento, como será desarrollado, constituirá el derecho de propiedad, y, específicamente, será el contenido o núcleo esencial de éste que sería el fundamento del principio en análisis. Por último, se analizará la autonomía del principio de capacidad contributiva en el sistema tributario constitucional, y cómo opera este, respecto a los demás principios jurídicos constitucionales materialesVersión original del auto

Maximizing Revenue in the Presence of Intermediaries

We study the mechanism design problem of selling $k$ items to unit-demand buyers with private valuations for the items. A buyer either participates directly in the auction or is represented by an intermediary, who represents a subset of buyers. Our goal is to design robust mechanisms that are independent of the demand structure (i.e. how the buyers are partitioned across intermediaries), and perform well under a wide variety of possible contracts between intermediaries and buyers. We first study the case of $k$ identical items where each buyer draws its private valuation for an item i.i.d. from a known $\lambda$-regular distribution. We construct a robust mechanism that, independent of the demand structure and under certain conditions on the contracts between intermediaries and buyers, obtains a constant factor of the revenue that the mechanism designer could obtain had she known the buyers' valuations. In other words, our mechanism's expected revenue achieves a constant factor of the optimal welfare, regardless of the demand structure. Our mechanism is a simple posted-price mechanism that sets a take-it-or-leave-it per-item price that depends on $k$ and the total number of buyers, but does not depend on the demand structure or the downstream contracts. Next we generalize our result to the case when the items are not identical. We assume that the item valuations are separable. For this case, we design a mechanism that obtains at least a constant fraction of the optimal welfare, by using a menu of posted prices. This mechanism is also independent of the demand structure, but makes a relatively stronger assumption on the contracts between intermediaries and buyers, namely that each intermediary prefers outcomes with a higher sum of utilities of the subset of buyers represented by it

Acute Intermittent Porphyria: Pathophysiology and Treatment

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90337/1/j.1875-9114.1984.tb03340.x.pd

Are non-contingent incentives more effective in motivating new behavior? Evidence from the field

Organizations and policymakers increasingly rely on economic incentives to prompt participation in activities amongst those who were previously not engaged. We ran a field experiment with a recycling program to examine incentives' effectiveness to motivate new behavior—i.e., attract non-recyclers. We compared standard contingent incentives (payment contingent on recycling) to non-contingent incentives (upfront unconditional payment) of different sizes. A high contingent incentive was as effective as a non-contingent incentive (of any size) in attracting people to the program, but this masked differences in who participated. Across incentive sizes, people who had never recycled were 5.8 times more likely to begin recycling with the program when given a non-contingent incentive (20.2%) than when offered a contingent one (3.5%). A second experiment conceptually replicated this effect in an online job market, showing that non-contingent incentives were substantially more effective in attracting previous non-compliers.ANID FONDECYT 1191745 Complex Engineering Systems Institute ANID APOYO/BASAL AFB180003Versión sometida a revisión - Preprin