Long-term effects of adolescent stress on neophobic behaviors in zebra finches are modulated by social context when in adulthood

Funding was provided by a BBSRC Research Fellowship to KAS and a University of St Andrews postgraduate scholarship to MGE.Experiencing stress during adolescence can increase neophobic behaviors in adulthood, but most tests have been conducted in the absence of conspecifics. Conspecifics can modulate responses to stressors, for example by acting as ‘social buffers’ to attenuate the aversive appraisal of stressors. Here, we investigate the long-term effects of adolescent stress on the behavioral responses to novel stimuli (a mild stressor) across social contexts in an affiliative passerine bird, the zebra finch. During early (days 40–60) or late (days 65–85) adolescence the birds (n = 66) were dosed with either saline or the hormone corticosterone (CORT). CORT was given in order to mimic a physiological stress response and saline was given as a control. In adulthood, the birds' behavioral responses to a novel environment were recorded in both the presence and absence of conspecifics. An acute CORT response was also quantified in adolescence and adulthood. Our findings show clear evidence of social context mediating any long-term effects of adolescent stress. In the presence of familiar conspecifics no treatment effects were detected. Individually, birds dosed with CORT in early adolescence were slower to enter a novel environment, spent more time perching in the same novel environment, and, if female, engaged in more risk assessment. Birds dosed in late adolescence were unaffected. No treatment effects were detected on CORT, but adolescents had a higher CORT concentration than adults. Our results are the first to suggest that familiar conspecifics in adulthood can buffer the long-term effects of stress that occurred during early adolescence.Publisher PDFPeer reviewe

Judicial Citation to Legislative History: Contextual Theory and Empirical Analysis

Judge Leventhal famously described the invocation of legislative history as the equivalent of entering a crowded cocktail party and looking over the heads of the guests for one\u27s friends. The volume of legislative history is so great and varied, some contend, that judges cite it selectively to advance their policy agendas. In this article, we employ positive political and contextual theories of judicial behavior to examine how judges use legislative history. We consider whether opinion-writing judges, as Judge Leventhal might suggest, cite legislative history from legislators who share the same political-ideological perspective as the opinion-writing judge? Or do judges make such choices in a broader context than Judge Levanthal\u27s statement suggests. We posit that an opinion writing judge would cite legislative statements supporting an outcome preferred by the opinion-writing judge, when such statements come from legislators who share the same political-ideological perspective as the opinion-writing judge\u27s colleagues or superiors. This should be so regardless of whether the cited legislator shares the broader perspectives of the opinion-writing judge himself. Put in Leventhal\u27s terms, instead of looking for their own ideological friends, judges look over the heads of the guests for the legislative friends of the judge\u27s colleagues on the bench (or superiors on higher benches). We test this approach with court opinion data gathered from LEXIS and find evidence of hierarchy (high court oversight) and panel (co-members on a court) effects in citation to legislative history, effects that appear related to the political-ideological identification of judges who review or are co-members on a panel of the authoring judge. Specifically, we find that the higher the proportion of Republicans in the reviewing court or sitting on the same three-judge panel, the higher the proportion of legislative history cites that will be to Republican legislators, independent of the political orientation of the authoring judge

Judicial Citation to Legislative History: Contextual Theory and Empirical Analysis

Judge Leventhal famously described the invocation of legislative history as the equivalent of entering a crowded cocktail party and looking over the heads of the guests for one\u27s friends. The volume of legislative history is so great and varied, some contend, that judges cite it selectively to advance their policy agendas. In this article, we employ positive political and contextual theories of judicial behavior to examine how judges use legislative history. We consider whether opinion-writing judges, as Judge Leventhal might suggest, cite legislative history from legislators who share the same political-ideological perspective as the opinion-writing judge? Or do judges make such choices in a broader context than Judge Levanthal\u27s statement suggests. We posit that an opinion writing judge would cite legislative statements supporting an outcome preferred by the opinion-writing judge, when such statements come from legislators who share the same political-ideological perspective as the opinion-writing judge\u27s colleagues or superiors. This should be so regardless of whether the cited legislator shares the broader perspectives of the opinion-writing judge himself. Put in Leventhal\u27s terms, instead of looking for their own ideological friends, judges look over the heads of the guests for the legislative friends of the judge\u27s colleagues on the bench (or superiors on higher benches). We test this approach with court opinion data gathered from LEXIS and find evidence of hierarchy (high court oversight) and panel (co-members on a court) effects in citation to legislative history, effects that appear related to the political-ideological identification of judges who review or are co-members on a panel of the authoring judge. Specifically, we find that the higher the proportion of Republicans in the reviewing court or sitting on the same three-judge panel, the higher the proportion of legislative history cites that will be to Republican legislators, independent of the political orientation of the authoring judge

Group housing during adolescence has long-term effects on the adult stress response in female, but not male, zebra finches (Taeniopygia guttata)

Funding was provided by a BBSRC David Phillips Research Fellowship to KAS and a University of St Andrews postgraduate scholarship to MGE.Adolescent social interactions can have long-term effects on physiological responses to stressors in later-life. A larger adolescent group size can result in higher stressor-induced secretion of glucocorticoids in adulthood. The effect may be due to a socially-mediated modulation of gonadal hormones, e.g. testosterone. However, group size (number of animals) has been conflated with social density (space per animal). Therefore it is hard to determine the mechanisms through which adolescent group size can affect the stress response. The current study aimed to tease apart the effects of group size and social density during adolescence on the physiological stress response and gonadal hormone levels in adulthood. Adolescent zebra finches were housed in groups varying in size (2 vs. 5 birds per cage) and density (0.03m3 vs. 0.06m3 per bird) during early adolescence (day 40-60). Density was only manipulated in birds raised in groups of five. Glucocorticoid concentration secreted in response to a standard capture and restraint stressor was quantified in adolescence (day 55±1) and adulthood (day 100+). Basal gonadal hormones concentrations (male testosterone, female estradiol) were also quantified in adulthood. Female birds housed in larger groups, independent of social density, secreted a higher glucocorticoid concentration 45 mins into restraint regardless of age, and had higher peak glucocorticoid concentration in adulthood. Adult gonadal hormone concentrations were not affected by group size or density. Our results suggest that group size, not density, is a social condition that influences the development of the endocrine response to stressors in female zebra finches, and that these effects persist into adulthood. The findings have clear relevance to the social housing conditions necessary for optimal welfare in captive animals, but also elucidate the role of social rearing conditions in the emergence of responses to stressors that may persist across the lifespan and affect fitness of animals in wild populations.Publisher PDFPeer reviewe

Adolescent stress and social experiences : developmental antecedents of adult behavioural responses to unfamiliar stimuli and the underlying neuroendocrine mechanisms

During adolescence, animals leave the natal home and interact with potentially threatening stimuli (i.e. stressors), e.g. unfamiliar environments and conspecifics. Adolescent stressors can result in fewer interactions with unfamiliar stimuli in adulthood, plausibly due to sustained effects of glucocorticoid exposure on stress physiology (e.g. glucocorticoid secretion and receptor expression). The current thesis tested the hypothesis that adolescent glucocorticoid exposure and social experiences act as stressors by quantifying the effects of the adolescent experiences on behavioural responses to unfamiliar stimuli and the underlying neuroendocrine mechanisms when in adulthood using two captive species, zebra finches and rats. In study one, adolescent zebra finches were dosed with the glucocorticoid corticosterone. In adulthood, birds dosed with corticosterone in early adolescence took longer to enter an unfamiliar environment when tested individually and had lower expression of the glucocorticoid receptor GR in the hippocampus and hypothalamus, brain regions that regulate stress responses. Glucocorticoids therefore appear to be an endocrine mechanism behind the long-term effects of adolescent stress. Subsequent studies explored whether higher social density and more unfamiliar social interactions during adolescence act as stressors. In study two, early adolescent zebra finches were housed in groups varying in conspecific number and density. In adulthood, females raised in larger groups secreted a higher stressor-induced corticosterone concentration and, if raised at lower density, spent more time in an unfamiliar environment when group housed. In study three, adolescent female rats were housed in familiar pairs or exposed to unfamiliar conspecifics. Unfamiliar adolescent interactions had no effects on responses to unfamiliar environments or stress physiology in adulthood, but heightened ultrasonic call rates. In this thesis, adolescent social experiences do not act like stressors, but modulate (especially female) social behaviour. Adolescent stressors and social experiences therefore have distinct effects on responses to unfamiliar stimuli and stress physiology that are maintained into adulthood

Social experience during adolescence in female rats increases 50 kHz ultrasonic vocalizations in adulthood, without affecting anxiety-like behavior

Funding was provided by a University of St Andrews postgraduate studentship to MGE.Adolescents are highly motivated to engage in social interactions, and researchers have hypothesized that positive social relationships during adolescence can have long term, beneficial effects on stress reactivity and mental well‐being. Studies of laboratory rodents provide the opportunity to investigate the relationship between early social experiences and later behavioral and physiological responses to stressors. In this study, female Lister‐hooded rats (N = 12 per group) were either (a) provided with short, daily encounters (10 min/day) with a novel partner during mid‐adolescence (postnatal day 34–45; “social experience,” SE, subjects) or (b) underwent the same protocol with a familiar cagemate during mid‐adolescence (“control experience,” CE, subjects), or (c) were left undisturbed in the home cage (non‐handled “control,” C, subjects). When tested in adulthood, the groups did not differ in behavioral responses to novel environments (elevated plus maze, open field, and light‐dark box) or in behavioral and physiological (urinary corticosterone) responses to novel social partners. However, SE females emitted significantly more 50 kHz ultrasonic vocalizations than control subjects both before and after social separation from a familiar social partner, which is consistent with previous findings in male rats. Thus, enhanced adolescent social experience appears to have long‐term effects on vocal communication and could potentially modulate adult social relationships.PostprintPeer reviewe

Anti-VEGF for the Management of Diabetic Macular Edema

Diabetic retinopathy (DR) is an important cause of vision loss around the world, being the leading cause in the population between 20 and 60 years old. Among patients with DR, diabetic macular edema (DME) is the most frequent cause of vision impairment and represents a significant public health issue. Macular photocoagulation has been the standard treatment for this condition reducing the risk of moderate visual loss by approximately 50%. the role of vascular endothelial growth factor (VEGF) in DR and DME pathogenesis has been demonstrated in recent studies. This review addresses and summarizes data from the clinical trials that investigated anti-VEGF for the management of DME and evaluates their impact on clinical practice. the literature searches were conducted between August and October 2013 in PubMed and Cochrane Library with no date restrictions and went through the most relevant studies on pegaptanib, ranibizumab, bevacizumab, and aflibercept for the management of DME. the efficacy and safety of intravitreal anti-VEGF as therapy for DME have recently been proved by various clinical trials providing significantly positive visual and anatomical results. Regarding clinical practice, those outcomes have placed intravitreal injection of anti-VEGF as an option that must be considered for the treatment of DME.Fed Univ São Paulo UNIFESP, Dept Ophthalmol & Visual Sci, Retina Div, BR-04023062 São Paulo, BrazilUniv So Calif, Keck Sch Med, Dept Ophthalmol, Doheny Eye Inst, Los Angeles, CA USAGoethe Univ Frankfurt, Dept Ophthalmol, D-60590 Frankfurt, GermanyFed Univ São Paulo UNIFESP, Dept Ophthalmol & Visual Sci, Retina Div, BR-04023062 São Paulo, BrazilWeb of Scienc

Temperature response measurements from eucalypts give insight into the impact of Australian isoprene emissions on air quality in 2050

Predicting future air quality in Australian cities dominated by eucalypt emissions requires an understanding of their emission potentials in a warmer climate. Here we measure the temperature response in isoprene emissions from saplings of four different Eucalyptus species grown under current and future average summertime temperature conditions. The future conditions represent a 2050 climate under Representative Concentration Pathway 8.5, with average daytime temperatures of 294.5 K. Ramping the temperature from 293 to 328 K resulted in these eucalypts emitting isoprene at temperatures 4–9 K higher than the default maximum emission temperature in the Model of Emissions of Gases and Aerosols from Nature (MEGAN). New basal emission rate measurements were obtained at the standard conditions of 303 K leaf temperature and 1000 µmol m−2 s−1 photosynthetically active radiation and converted into landscape emission factors. We applied the eucalypt temperature responses and emission factors to Australian trees within MEGAN and ran the CSIRO Chemical Transport Model for three summertime campaigns in Australia. Compared to the default model, the new temperature responses resulted in less isoprene emission in the morning and more during hot afternoons, improving the statistical fit of modelled to observed ambient isoprene. Compared to current conditions, an additional 2 ppb of isoprene is predicted in 2050, causing hourly increases up to 21 ppb of ozone and 24-hourly increases of 0.4 µg m−3 of aerosol in Sydney. A 550 ppm CO2 atmosphere in 2050 mitigates these peak Sydney ozone mixing ratios by 4 ppb. Nevertheless, these forecasted increases in ozone are up to one-fifth of the hourly Australian air quality limit, suggesting that anthropogenic NOx should be further reduced to maintain healthy air quality in future

Microbial inactivation:gaseous or aqueous ozonation

[Image: see text] For decades, ozone has been known to have antimicrobial properties when dissolved or generated in water and when utilized in its gaseous form on different substrates. This property (the ability to be used in air and water) makes it versatile and applicable to different industries. Although the medium of ozonation depends on the specific process requirements, some industries have the inherent flexibility of medium selection. Thus, it is important to evaluate the antimicrobial efficacy in both media at similar concentrations, an endeavor hardly reported in the literature. This study provides insights into ozone’s efficacy in air and water using two Gram-negative bacteria (Escherichia coli NTCC1290 and Pseudomonas aeruginosa NCTC10332), two Gram-positive bacteria (Staphylococcus aureus ATCC25923 and Streptococcus mutans), and two fungi (Candida albicans and Aspergillus fumigatus). For gaseous ozonation, we utilized a custom-made ozone chamber (equipped with ultraviolet lamps), whereas an electrolysis oxygen radical generator was applied for ozone generation in water. During gaseous ozonation, the contaminated substrates (fabric swatches inoculated with bacterial and fungal suspensions) were suspended in the chamber, whereas the swatches were immersed in ozonated water for aqueous ozone treatment. The stability of ozone nanobubbles and their resulting impact on the aqueous disinfection efficiency were studied via dynamic light scattering measurements. It was observed that ozone is more effective in air than in water on all tested organisms except Staphylococcus aureus. The presented findings allow for the adjustment of the treatment conditions (exposure time and concentration) for optimal decontamination, particularly when a certain medium is preferred for ozonation