Was It Something I Ate? Implementation of the FDA Seafood HACCP Program

We use FDA’s seafood inspection records to examine: (i) how FDA has targeted its inspections under HACCP regulation; (ii) the effects of FDA inspections on compliance with both HACCP and plant sanitation standards; and (iii) the relationship between HACCP regulations and pre-existing sanitation standards. We use a theoretical model of enforcement to derive hypotheses about FDA’s targeting of inspections and firms’ patterns of compliance. We test those hypotheses using econometric models of inspection and compliance. Contrary to the predictions of the theoretical model and to FDA’s own stated policies, FDA does not seem to have targeted inspections based on product risk or past compliance performance. Firms’ compliance strategies seemed to be broadly in accord with the predictions of the theoretical model. The threat of inspection increased the likelihood of compliance, although the deterrent effect was statistically significant for sanitation standards but not for HACCP. Firms tend to persist in compliance status, especially with respect to sanitation standards. Contrary to FDA’s presupposition, however, HACCP compliance does not improve compliance with sanitation standards, suggesting that the two are not complementary.HACCP, Food safety, Seafood, Enforcement, Regulatory compliance, Regulation

Measuring the health effects of air pollution : to what extent can we really say people are dying from bad air?

Estimation of the effects of environmental impacts is a major focus of current theoretical and policy research in environmental economics. Such estimates are used to set regulatory standards for pollution exposure; design appropriate environmental protection and damage mitigation strategies; guide the assessment of environmental impacts; and measure public willingness to pay for environmental amenities. It is a truism that the effectiveness of such strategies depends crucially on the quality of the estimates used to inform them. However, this paper argues that in respect to at least one area of the empirical literature - the estimation of the health impacts of air pollution using daily time series data - existing estimates are questionable and thus have limited relevance for environmental decision-making. By neglecting the issue of model uncertainty - or which models, among the myriad of possible models researchers should choose from to estimate health effects - most studies overstate confidence in their chosen model and underestimate the evidence from other models, thereby greatly enhancing the risk of obtaining uncertain and inaccurate results. This paper discusses the importance of model uncertainty for accurate estimation of the health effects of air pollution and demonstrates its implications in an exercise that models pollution-mortality impacts using a new and comprehensive data set for Toronto, Canada. The main empirical finding of the paper is that standard deviations for air pollution-mortality impacts become very large when model uncertainty is incorporated into the analysis. Indeed they become so large as to question the plausibility of previously measured links between air pollution and mortality. Although applied to the estimation of the effects of air pollution, the general message of this paper - that proper treatment of model uncertainty critically determines the accuracy of the resulting estimates - applies to many studies that seek to estimate environmental effects

Residential electricity pricing in China

The paper aims to evaluate the implications of the new residential pricing system in China by examining price and income elasticity of demand by different household types. We use pre-reform annual panel data for 29 provinces over a fourteen year period, from 1998 to 2011, applying feasible generalize least squares models. The price and income elasticities for household sector are -0.412, and 1.476 at nation level, -0.300 and 1.550 in urban areas and -0.522 and 1.093 in rural areas respectively. With regional effects, the price and income elasticities are -0.146 and 1.286 for urban households in coastal provinces and -0.772 and 1.259 for urban households in inland provinces respectively. The empirical results reveal that there is important heterogeneity in the responsiveness to electricity price changes according to household income level and location

Complement component 3 (C3) expression in the hippocampus after excitotoxic injury: role of C/EBPβ

[Background] The CCAAT/enhancer-binding protein β (C/EBPβ) is a transcription factor implicated in the control of proliferation, differentiation, and inflammatory processes mainly in adipose tissue and liver; although more recent results have revealed an important role for this transcription factor in the brain. Previous studies from our laboratory indicated that CCAAT/enhancer-binding protein β is implicated in inflammatory process and brain injury, since mice lacking this gene were less susceptible to kainic acid-induced injury. More recently, we have shown that the complement component 3 gene (C3) is a downstream target of CCAAT/enhancer-binding protein β and it could be a mediator of the proinflammatory effects of this transcription factor in neural cells.[Methods] Adult male Wistar rats (8–12 weeks old) were used throughout the study. C/EBPβ+/+ and C/EBPβ–/– mice were generated from heterozygous breeding pairs. Animals were injected or not with kainic acid, brains removed, and brain slices containing the hippocampus analyzed for the expression of both CCAAT/enhancer-binding protein β and C3.[Results] In the present work, we have further extended these studies and show that CCAAT/enhancer-binding protein β and C3 co-express in the CA1 and CA3 regions of the hippocampus after an excitotoxic injury. Studies using CCAAT/enhancer-binding protein β knockout mice demonstrate a marked reduction in C3 expression after kainic acid injection in these animals, suggesting that indeed this protein is regulated by C/EBPβ in the hippocampus in vivo.[Conclusions] Altogether these results suggest that CCAAT/enhancer-binding protein β could regulate brain disorders, in which excitotoxic and inflammatory processes are involved, at least in part through the direct regulation of C3.This work was supported by MINECO, Grant SAF2014-52940-R and partially financed with FEDER funds. CIBERNED is funded by the Instituto de Salud Carlos III. JAM-G was supported by CIBERNED. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe

Disrupting astrocyte-neuron lactate transfer persistently reduces conditioned responses to cocaine.

A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte-neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine

Synaptic tagging and capture in the living rat

In isolated hippocampal slices, decaying long-term potentiation can be stabilized and converted to late long-term potentiation lasting many hours, by prior or subsequent strong high-frequency tetanization of an independent input to a common population of neurons—a phenomenon known as ‘synaptic tagging and capture’. Here we show that the same phenomenon occurs in the intact rat. Late long-term potentiation can be induced in CA1 during the inhibition of protein synthesis if an independent input is strongly tetanized beforehand. Conversely, declining early long-term potentiation induced by weak tetanization can be converted into lasting late long-term potentiation by subsequent strong tetanization of a separate input. These findings indicate that synaptic tagging and capture is not limited to in vitro preparations; the past and future activity of neurons has a critical role in determining the persistence of synaptic changes in the living animal, thus providing a bridge between cellular studies of protein synthesis-dependent synaptic potentiation and behavioural studies of memory persistence

Impure Public Goods and Technological Interdependencies

Impure public goods represent an important group of goods. Almost every public good exerts not only effects which are public to all but also effects which are private to the producer of this good. What is often omitted in the analysis of impure public goods is the fact that – regularly – these private effects can also be generated independently of the public good. In our analysis we focus on the effects alternative technologies – independently generating the private effects of the public good – may have on the provision of impure public goods. After the investigation in an analytical impure public good model, we numerically simulate the effects of alternative technologies in a parameterized model for climate policy in Germany

Evolución y cinética de disipación de residuos de pirimetanil en frutas cítricas. Metodologías alternativas de aplicación

Los tratamientos poscosecha tradicionales han generado biotipos resistentes que hacen necesaria la búsqueda de alternativas de otros fungicidas en cítricos. Con este fin se plantean evaluar los niveles residuales y determinar curvas y cinética de disipación de pirimetanil en naranja Valencia, mandarina Clementina y Satsuma, utilizando QuEChERS, GC/NPD/MS. Se aplicaron concentraciones de pirimetanil de 300 y 1000mg/l, cera al agua al 18 % y quitosano. La simulación de transporte se realizó en cámara a 5°C y humedad relativa de 95 %. Los valores medios de pirimetanil depositados en la superficie de los frutos fueron de 500 a 700 y de 1000 a 1600μg/kg, para 300 y 1000mg/l aplicados respectivamente. Se observaron diferencias significativas entre las diferentes variedades, incluso a igual dosis de fungicida y recubrimiento. Las curvas de disipación en fruta responden a una cinética de primer orden, observándose mayor velocidad de disipación con quitosano. La mandarina Satsuma presentó los menores porcentajes de persistencia, entre 20-28 %, en tanto los frutos recubiertos con ceras entre 40-45 %. La pérdida de peso fue menor para frutas recubiertas con cera. Los resultados demostraron que es factible mantener el control fúngico utilizando menores dosis de pirimetanil y quitosano como recubrimiento, minimizando la contaminación ambiental

Caracterización de la contaminación en la región del Embalse Salto Grande

La contaminación ambiental y el deterioro de la calidad del agua son los mayores problemas asociados al uso de plaguicidas. Teniendo en cuenta que las prácticas agrícolas son las tradicionales en casi toda la región, estos plaguicidas pueden ingresar a los cursos de agua por diferentes mecanismos de transporte, tales como los procesos de lluvia-escorrentía. El objetivo principal de este trabajo fue efectuar el monitoreo de plaguicidas en el Embalse de Salto Grande en muestras de agua, sólidos suspendidos y sedimentos. El muestreo fue efectuado por personal de la Comisión Técnica Mixta de Salto Grande en el marco de un convenio específico. La metodología analítica involucró la extracción de los plaguicidas, organoclorados, organofosforados y de otras familias, de las diferentes matrices, los que se determinaron por cromatografía gaseosa con detectores selectivos e identificación por espectrometría de masa. Las fechas de mayor ocurrencia y niveles máximos de plaguicidas en cada sitio son coincidentes con las de las precipitaciones ocurridas y relacionadas con los cultivos aledaños. El análisis de componentes principales permitió la caracterización de la contaminación en los sitios y los resultados fueron comparados con niveles guías de calidad de agua, contribuyendo al diagnóstico de la situación en la regió

A Weak Bargaining Set for Contract Choice Problems

In this paper, we consider the problem of choosing a set of multi-party contracts, where each coalition of agents has a non-empty finite set of feasible contracts to choose from. We call such problems, contract choice problems. The main result of this paper states that every contract choice problem has a non-empty weak bargaining set. The need for such a solution concept which is considerably weaker than the core arises, since it is well known that even for very simple contract choice problems, the core may be empty. We also show by means of an example that the bargaining set due to Mas-Colell (1989), as well as a weaker version of it, may be empty for contract choice problems, thereby implying that the weakening we suggest is in some ways tigh