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Glyphosate is the active ingredient of some of the most highly produced and used herbicides worldwide. The intensive applications of glyphosate-based herbicides and its half-life in water lead to its presence in many aquatic ecosystems. Whereas recent studies have reported neurotoxic effects of glyphosate including autism-related effects, most of them used extremely high (mg/L to g/L) concentrations, so it is still unclear if chronic, low environmentally relevant concentrations of this compound (ng/L to μg/L) can induce neurotoxicity. In this study we analyzed the neurotoxicity of glyphosate in adult zebrafish after waterborne exposure to environmentally relevant concentrations (0.3 and 3 μg/L) for two weeks. Our data showed that exposed fish presented a significant impairment of exploratory and social behaviors consistent with increased anxiety. The anterior brain of the exposed fish presented a significant increase in dopamine and serotonin levels, as well as in the DOPAC/dopamine and homovanillic acid/dopamine turnover ratios. Moreover, the expression of genes involved in the dopaminergic system, as th1, th2, comtb, and scl6a3 was downregulated. Finally, the brain of exposed fish presented a significant increase in the catalase and superoxide dismutase activities, with a concomitant decrease of glutathione stores. These changes in the antioxidant defense system are consistent with the observed increase in oxidative stress, reflected by the increase in the levels of lipid peroxidation in the brain. The presented results show that current glyphosate concentrations commonly found in many aquatic ecosystems may have detrimental consequences on fish survival by decreasing exploration of the environment or altering social interactions. Furthermore, as zebrafish is also a vertebrate model widely used in human neurobehavioral studies, these results are relevant not only for environmental risk assessment, but also for understanding the risk of chronic low-dose exposures on human health. ; This work was supported by the Spanish Government with FEDER Funds (CTM2017-83242-R; D.R.) and the network of recognized research groups by the Catalan Government (2017 SGR_902). J.B. was supported by a Spanish fellowship PRE2018-083513. Mention of specific products or trade names does not indicate endorsement by the US federal government. ; Peer reviewed

Personal bankruptcy, unemployment insurance, and Aid to Families with Dependent Children provide income and wealth insurance. Because they have similar purposes, it should not be surprising that some households use more than one of these programs or that the programs are substitutes. This study contributes to the personal bankruptcy literature by examining this interaction and finds that increases in unemployment benefits decrease the probability of bankruptcy. (JEL D12, K35)

Regulatory costs on aquaculture farms have been shown to be of a magnitude that warrants additional analysis. The drivers of farm-level costs of fish health inspections were identified in this study from national survey data on U.S. salmonid farms. The greatest costs identified were related primarily to state fish health requirements for inspection and testing to certify that fish are free of specific pathogens prior to approval of necessary permits to sell and/or transport animals. Fish health inspection costs included laboratory testing, farm personnel time, veterinary fees, and shipping samples to laboratories, with laboratory testing and the value of farm personnel time being the most expensive components. Principal cost drivers were the number of tests and whether required sampling was farmwide or for each lot as identified by the collector. Farmers who primarily sold into recreational markets had greater fish health costs than farmers who primarily sold food fish because of the greater numbers of species and size-/age-classes of salmonids on their farms. Regulatory requirements to test all species and size-/age-classes on farms increased inspection costs by increasing the total number of tests, the total value of fish sacrificed, and shipping costs. Consequently, for farms with more than one species or more than one size-/age-class, annual farm-level testing was less costly than annual lot-based testing. Increased numbers of tests in a given year, although reported by only a few respondents, can increase costs dramatically and turn profitable farms unprofitable, even food fish farms. Smaller salmonid farms experienced disproportionately greater inspection cost burdens than did larger farms. The fish health inspection scenario of only one annual inspection of only the most susceptible species and size-/age-class showed a cost burden that did not generate economic distress, even on smaller salmonid farms. Other scenarios modeled (based on survey data) that included lot-based surveys of multiple species and size-/age-classes resulted in substantially greater fish health inspection costs that led to unprofitability for various farm sizes and business types. Study results suggest that implementing Comprehensive Aquaculture Health Program Standards might allow for risk- and pathogen-based reductions in the total number of inspections and fish sampled while maintaining equivalent or greater health status compared to current methods. American Fisheries Society-Fish Health Section Blue Book inspection methods are interpreted and applied inconsistently across states and generally yield lot- rather than farm-level health attestations because the history of testing results, risk assessment, and biosecurity practices are not typically taken into account. The cost effects of alternative fish health sampling and testing requirements should be considered in decisions and policy on fish health regulation. ; Western Regional Aquaculture Center Agreement Award [542209]; United States Trout Farmers Association; USDA-APHIS Cooperative Agreement Award [422526] ; Published version ; We thank all of the individuals who contributed to the planning, implementation, and completion of this study, particularly our project collaborators Gary Fornshell, Fred Conte, and William Hanshumaker. In addition, Debra Sloan, Jeff Hinshaw, Myron Kebus, Chris Weeks, and Matt Smith were very helpful. We appreciate the anonymous reviewers for providing useful insights into the nuances of fish health sampling and testing. We especially thank all of the producers who spent the time to participate and contribute data for this study. This study was funded by the Western Regional Aquaculture Center Agreement Award 542209, the United States Trout Farmers Association, and USDA-APHIS Cooperative Agreement Award 422526. There is no conflict of interest declared in this article. ; Public domain authored by a U.S. government employee

Lotic systems within the Great Plains are characterized by highly fluctuating conditions through both space and time. Fishes inhabiting these systems have adopted specific life-history strategies to survive in such environments; however, anthropogenic disturbance to prairie streams has resulted in declines and extirpation of many native stream fishes. Terrestrial protected areas (i.e., parks and reserves) are designated to support native flora and fauna and, it is assumed, to provide protection to native fishes. We assessed the presence and relative abundance of stream fish populations within protected areas along the Niobrara River in western Nebraska based on data collected during 1979, 1989, 2008, and 2011. The spatial extent of protection, landscape changes resulting in degraded physiochemical parameters, and introduced species may reduce the effectiveness of these terrestrial protected areas in protecting native fishes in Great Plains stream environments.

Les débats récents sur les conséquences de la robotisation sur l'emploi (combien restera-t-il d'emplois non automatisés ?) posent en filigrane la question de la capacité des sociétés modernes à offrir un emploi à chacun à temps plein. Le temps de travail diminue-t-il nécessairement avec le progrès technologique et le développement économique ? C'est pour répondre à cette question que Jonathan Gershuny et Kimberly Fisher ont étudié les résultats d'enquêtes sur l'emploi du temps des individus dans 16 pays au cours des cinq dernières décennies : ils présentent ici les tendances qui s'en dégagent concernant le travail au sens large. Après un rappel historique montrant comment ont évolué les aspirations et rapports au travail et au loisir depuis le XIX e siècle (s'appuyant principalement sur les théories de Veblen), les auteurs présentent les différentes enquêtes sur lesquelles s'appuie leur analyse ainsi que la méthodologie utilisée. Puis ils relèvent plusieurs grandes tendances : une certaine constance historique et une certaine similitude entre pays s'agissant du temps consacré au travail (rémunéré + non rémunéré) sur les 55 dernières années ; une convergence hommes-femmes dans les évolutions et une quasi-équité entre les sexes concernant le temps consacré à l'ensemble du travail (rémunéré + non rémunéré) ; un apparent nivellement historique de ce temps de travail autour de huit heures et demie par jour ; et une inversion de la variation de la répartition travail / loisir selon le capital humain (ce sont aujourd'hui les plus diplômés qui travaillent le plus), que les auteurs associent à une croissance de la part de l'« exploit » au détriment de celle du « labeur » (selon la terminologie de Veblen) dans le travail rémunéré des sociétés de ce début de XXI e siècle. S.D.

Internet shutdowns are now commonplace in some African states, particularly those under authoritarian rule or impacted by instability and insecurity. Explanations for these – usually state-imposed – disruptions generally focus on a government's repressive intent, and desire to restrict or …

The search for security has become an almost permanent feature of the contemporary lived experience and what Brian Massumi has called an 'operative logic' for states across the globe. The modern study – and practice – of security has, nonetheless, been largely concerned with the protection, preservation and sustaining of the material, the tangible and the visible. For many people around the world, however, feelings of security also derive from understandings of an individual or community's relationships with invisible and spiritual forces. Religious devotion and divine protection represent a central plank of security for many, just as fears of divine retribution, demonic possession or witchcraft feature as a central dimension of insecurity for many others. This remains, however, a significant blindspot in much of security studies – and, indeed, often eludes and challenges state authority as much as it intersects with and enhances it. Drawing on fieldwork undertaken in northwestern Uganda, this study reflects critically on the provenance and implications of this blindspot and argues for an expanded understanding of what 'counts' as (in)security. In doing so, the article emphasizes the global character of spiritual (in)security and the challenges an understanding of (in)security that encompasses this pose to longstanding scholarly and practitioner associations of (in)security with state authority.

This study uses questions on household repayment problems from the Panel Study of Income Dynamics to examine how the transition from marriage to divorce affects default rates by gender. The results show that divorced women are more likely to have repayment problems than divorced men & married-couple households. Further analysis reveals that divorced women who are receiving welfare are significantly less likely to default. Because average welfare benefits decreased in the early 1990s, the results suggest that this decrease provides a partial explanation for why the default rate increased between 1991 & 1995 for divorced women. The effect of welfare on the default rates of divorced men & married couples is insignificant, & there is no evidence that receiving child support & alimony payments significantly affects the probability of default. Tables, Figures, References. Adapted from the source document. COPIES ARE AVAILABLE FROM: HAWORTH DOCUMENT DELIVERY CENTER, The Haworth Press, Inc., 10 Alice Street, Binghamton, NY 13904-1580