Level raising for automorphic representations of GL(2n)

To each regular algebraic, conjugate self-dual, cuspidal automorphic representation $\Pi$ of $\mathrm{GL}(N)$ over a CM number field $E$ (or, more generally, to a regular algebraic isobaric sum of conjugate self-dual, cuspidal representations), we can attach a continuous $\ell$-adic Galois representation $r(\Pi)$ of the absolute Galois group of $E$. The residual Galois representation $\overline{r}(\Pi):\mathrm{Gal}(\overline{E}/E)\to\mathrm{GL}_N(\overline{\mathbb{F}}_\ell)$ of $\pi$ is defined to be the semisimplification of the reduction of $r(\Pi)$ (modulo the maximal ideal of $\overline{\mathbb{Z}}_\ell$), with respect to any invariant $\overline{\mathbb{Z}}_\ell$-lattice. The aim of this thesis is to prove a level raising theorem for automorphic representations of $\mathrm{GL}(2n)$. More precisely, given a regular algebraic automorphic representation $\Pi$ of $\mathrm{GL}(2n)$ over $E$, which is either unitary, conjugate self-dual and cuspidal or an isobaric sum $\Pi_1 \boxplus \Pi_2$ of two unitary, conjugate self-dual cuspidal representations of $\mathrm{GL}(n)$, we want to construct a unitary, conjugate self-dual cuspidal representation $\Pi'$ of $\mathrm{GL}(2n)$ that has the same residual Galois representation as $\Pi$ and whose component at a finite place $w$ of $E$ is an unramified twist of the Steinberg representation. We prove that this is possible, after replacing $\Pi$ with its base change along a CM biquadratic extension, under certain assumptions on $\Pi$ (including a local obstruction at the place $w$). Our proof uses the results of Kaletha, Minguez, Shin and White on the endoscopic classification of representations of (inner forms of) unitary groups to descend $\Pi$ to an automorphic representation of a totally definite unitary group $G$ over the maximal totally real subfield of $E$. We then prove a level raising theorem for the group $G$; we do this by proving an analogue of “Ihara's lemma” for $G$, using the strong approximation theorem for the derived subgroup of $G$

Assessing Children’s Dietary Pesticide Exposure: Direct Measurement of Pesticide Residues in 24-Hr Duplicate Food Samples

Background: The data presented here are a response to calls for more direct measurements of pesticide residues in foods consumed by children and provide an opportunity to compare direct measures of pesticide residues in foods representing actual consumption with those reported by the U.S. Department of Agriculture Pesticide Data Program. Objective: We measured pesticide residues in 24-hr duplicate food samples collected from a group of 46 young children participating in the Children’s Pesticide Exposure Study (CPES). Methods: Parents were instructed to collect 24-hr duplicate food samples of all conventional fruits, vegetables, and fruit juices equal to the quantity consumed by their children, similarly prewashed/prepared, and from the same source or batch. Individual or composite food items were analyzed for organophosphate (OP) and pyrethroid insecticide residues. Results: We collected a total of 239 24-hr duplicate food samples collected from the 46 CPES children. We found 14% or 5% of those food samples contained at least one OP or pyrethroid insecticide, respectively. We measured a total of 11 OP insecticides, at levels ranging from 1 to 387 ng/g, and three pyrethroid insecticides, at levels ranging from 2 to 1,133 ng/g, in children’s food samples. We found that many of the food items consumed by the CPES children were also on the list of the most contaminated food commodities reported by the Environmental Working Group. Conclusions: The frequent consumption of food commodities with episodic presence of pesticide residues that are suspected to cause developmental and neurological effects in young children supports the need for further mitigation

Multi residual analysis of 45 pesticides from beehive products: application of a simple extraction method

En este trabajo se presenta la aplicación de una metodología de extracción sencilla y rápida llamada QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) que ha sido utilizada fundamentalmente para el análisis de trazas de pesticidas en frutas y hortalizas, que con pequeñas modificaciones es adaptable tanto para el análisis de cera como miel. El solvente de extracción es acetonitrilo y la misma se realiza a temperatura ambiente agregando agua para miel y a 80°C en baño de agua para cera, luego se realiza una purificación que consiste en colocar el extracto en freezer a -20 °C durante 15 hs y filtrar. Una purificación más exhaustiva se logra agregando luego PSA (Primary and Secondary Amine). El método presentó recuperaciones entre 70 y 120 % con DSR menores a 20 % para más del 90 % de los pesticidas evaluados en ambas matrices analizados por LC-MS/MS.The application of a quick and simple methodology named QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) is presented. It has been mainly applied for the analysis of pesticide residues in fruits and vegetables, but with small modifications is suitable for the analysis of beeswax and honey. The extraction is made with acetonitrile at room temperature adding water for honey and at 80 °C in water bath for beeswax, it is then followed by freeze-out clean-up (-20 °C in freezer for 15 hs). Further clean-up of the extract is achieved adding PSA (Primary and Secondary Amine) afterwards. The method presented recoveries in both matrices between 70 and 120 % with RSD below 20 % for more than 90 % of the evaluated pesticides analyzed by LC-MS/MS.Asociación de Universidades Grupo Montevide

Multi residual analysis of 45 pesticides from beehive products: application of a simple extraction method

En este trabajo se presenta la aplicación de una metodología de extracción sencilla y rápida llamada QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) que ha sido utilizada fundamentalmente para el análisis de trazas de pesticidas en frutas y hortalizas, que con pequeñas modificaciones es adaptable tanto para el análisis de cera como miel. El solvente de extracción es acetonitrilo y la misma se realiza a temperatura ambiente agregando agua para miel y a 80°C en baño de agua para cera, luego se realiza una purificación que consiste en colocar el extracto en freezer a -20 °C durante 15 hs y filtrar. Una purificación más exhaustiva se logra agregando luego PSA (Primary and Secondary Amine). El método presentó recuperaciones entre 70 y 120 % con DSR menores a 20 % para más del 90 % de los pesticidas evaluados en ambas matrices analizados por LC-MS/MS.The application of a quick and simple methodology named QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) is presented. It has been mainly applied for the analysis of pesticide residues in fruits and vegetables, but with small modifications is suitable for the analysis of beeswax and honey. The extraction is made with acetonitrile at room temperature adding water for honey and at 80 °C in water bath for beeswax, it is then followed by freeze-out clean-up (-20 °C in freezer for 15 hs). Further clean-up of the extract is achieved adding PSA (Primary and Secondary Amine) afterwards. The method presented recoveries in both matrices between 70 and 120 % with RSD below 20 % for more than 90 % of the evaluated pesticides analyzed by LC-MS/MS.Asociación de Universidades Grupo Montevide

Multi residual analysis of 45 pesticides from beehive products: application of a simple extraction method

En este trabajo se presenta la aplicación de una metodología de extracción sencilla y rápida llamada QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) que ha sido utilizada fundamentalmente para el análisis de trazas de pesticidas en frutas y hortalizas, que con pequeñas modificaciones es adaptable tanto para el análisis de cera como miel. El solvente de extracción es acetonitrilo y la misma se realiza a temperatura ambiente agregando agua para miel y a 80°C en baño de agua para cera, luego se realiza una purificación que consiste en colocar el extracto en freezer a -20 °C durante 15 hs y filtrar. Una purificación más exhaustiva se logra agregando luego PSA (Primary and Secondary Amine). El método presentó recuperaciones entre 70 y 120 % con DSR menores a 20 % para más del 90 % de los pesticidas evaluados en ambas matrices analizados por LC-MS/MS.The application of a quick and simple methodology named QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) is presented. It has been mainly applied for the analysis of pesticide residues in fruits and vegetables, but with small modifications is suitable for the analysis of beeswax and honey. The extraction is made with acetonitrile at room temperature adding water for honey and at 80 °C in water bath for beeswax, it is then followed by freeze-out clean-up (-20 °C in freezer for 15 hs). Further clean-up of the extract is achieved adding PSA (Primary and Secondary Amine) afterwards. The method presented recoveries in both matrices between 70 and 120 % with RSD below 20 % for more than 90 % of the evaluated pesticides analyzed by LC-MS/MS.Asociación de Universidades Grupo Montevide