123 research outputs found

    The Racial Pandemic: Positive Behavior Intervention Support as an Asymptomatic Carrier of Racism

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    In an attempt to close the discipline gap, school systems have replaced traditional exclusionary practices with alternative interventions such as Positive Behavior Intervention Support (PBIS). PBIS, as an alternative to exclusionary discipline practices, does little to help historically oppressed youth, specifically, because it denies the presence and value of race. This attempt to be race-neutral results in racist discipline outcomes. PBIS presents harmful outcomes for early childhood and elementary-aged children, as it normalizes children to the disciplinary structures that result in high school dropouts and other negative outcomes for older youth. Exploring this program aids in understanding the limitations of color-evasive policies in education and society at large. In this article, the authors explore failings of PBIS and argue for the adoption of color-conscious approaches that engage in co-construction of pedagogy, curriculum, accountability norms, and expectations (Milner et al., 2018)

    Sex allocation theory reveals a hidden cost of neonicotinoid exposure in a parasitoid wasp

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    P.R.W. was funded by the University of Stirling, C.V.B. and S.M.G. were funded by Nuffield Research Placements and N.C., J.G. and D.M.S. were funded by NERC (NE/J024481/1).Sex allocation theory has proved to be one the most successful theories in evolutionary ecology. However, its role in more applied aspects of ecology has been limited. Here we show how sex allocation theory helps uncover an otherwise hidden cost of neonicotinoid exposure in the parasitoid wasp Nasonia vitripennis. Female N. vitripennis allocate the sex of their offspring in line with Local Mate Competition (LMC) theory. Neonicotinoids are an economically important class of insecticides, but their deployment remains controversial, with evidence linking them to the decline of beneficial species. We demonstrate for the first time to our knowledge, that neonicotinoids disrupt the crucial reproductive behaviour of facultative sex allocation at sub-lethal, field-relevant doses in N. vitripennis. The quantitative predictions we can make from LMC theory show that females exposed to neonicotinoids are less able to allocate sex optimally and that this failure imposes a significant fitness cost. Our work highlights that understanding the ecological consequences of neonicotinoid deployment requires not just measures of mortality or even fecundity reduction among non-target species, but also measures that capture broader fitness costs, in this case offspring sex allocation. Our work also highlights new avenues for exploring how females obtain information when allocating sex under LMC.Publisher PDFPeer reviewe

    A Comparison of Four Models of Delay Discounting in Humans

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    The present study compared four prominent models of delay discounting: a one-parameter exponential decay, a one-parameter hyperbola (Mazur, 1987), a two-parameter hyperboloid in which the denominator is raised to a power (Green and Myerson, 2004), and a two-parameter hyperbola in which delay is raised to a power (Rachlin, 2006). Sixty-four college undergraduates made choices between hypothetical monetary rewards, one immediate and one delayed, and the fit of the four models to their data was assessed. All four equations accounted for a large proportion of the variance at both the group and the individual levels, but the exponents of both two-parameter models were significantly less than 1.0 at the group level, and frequently so at the individual level. Taken together, these results strongly suggest that more than one parameter is needed to accurately describe delay discounting by humans. Notably, both the Rachlin and the Green and Myerson models accounted for more than 99% of the variance at the group level and for 96% of the variance in the median individual. Because both models provide such good descriptions of the data, model selection will need to be based on other grounds

    The fast response of volcano-seismic activity to intense precipitation: Triggering of primary volcanic activity by rainfall at SoufriĂšre Hills Volcano, Montserrat

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    One-minute resolution time series of rainfall and seismic data from the Soufriere Hills Volcano, Montserrat are analysed to explore the mechanism of external forcing of volcanic eruptions by rainfall over three years of activity. The real-time seismic amplitude (RSAM) shows a narrow, statistically significant, peak within 30 min after the start of intense rainfall events, and a much broader peak with a lag of 6?40 h. The classified seismic events indicate that the volcanic response to rainfall begins at the surface and gradually penetrates deeper into the dome, as there is an increase in the pseudo-magnitude of: surface rockfall events (including pyroclastic flows) with lags from the first 30 min to 40 h, long-period rockfalls (from shallow degassing) at lags of 4 and 14 h, and long-period and hybrid events (source depth approximately 1 km) with lags at 14 and 24 h after the start of rainfall events. There was no rainfall-related change in deeper, volcano-tectonic activity. There was no change in the frequency of any type of classified event, indicating that the rainfall acts to modulate existing, internal processes, rather than generating new events itself. These robust results are due to many (229) different rainfall events, and not just to a few, large magnitude cases. The rainfalltriggered volcanic activity examined here is consistent with a model of fast, shallow interactions with rainfall at the dome surface, after which, a deeper dome collapse follows

    Case report: Low dose dexmedetomidine infusion for the management of hypoglycemia in a dog with an insulinoma

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    ObjectiveTo describe the use of a low dose dexmedetomidine infusion as preoperative treatment for hypoglycemia secondary to a functional pancreatic tumor in a dog.Case summaryAn 8.7-year-old castrated male Hungarian Vizsla presented for further evaluation of persistent hypoglycemia after the referring veterinarian established a tentative diagnosis of insulinoma based on paired insulin and glucose measurements. Abdominal ultrasound and computed tomography demonstrated evidence of a pancreatic mass with possible hepatic metastases. Attempts to aspirate the lesions under ultrasound guidance were unsuccessful, and the dog was hospitalized overnight for planned surgical resection of the presumed pancreatic tumor and biopsy of the hepatic lesions the following day. In response to a progressive increase in patient anxiety and agitation trazodone was prescribed ~5 mg/kg orally every 8 h and gabapentin at ~7 mg/kg every 8 h. As the dog continued to remain anxious dexmedetomidine at a dose of 1 mcg/kg was administered intravenously immediately followed with an infusion of dexmedetomidine at 1 mcg/kg/h. The anxious behaviors were successfully controlled with minimal cardiovascular side effects. Serial blood glucose measurements obtained during this time demonstrated euglycemia. The dog remained euglycemic while receiving dexmedetomidine for the remainder of the pre-operative period and for duration of hospitalization following surgical resection and biopsy.New or unique information providedThis case report demonstrates a possible role for dexmedetomidine to counteract hypoglycemia in dogs with insulinomas

    Sperm blocking is not a male adaptation to sperm competition in a parasitoid wasp

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    This work was supported by a NERC Doctoral Training Grant studentship to RAB. Data archived in Dryad Digital Repository at doi:10.5061/dryad.t0877The extent to which sperm or ejaculate-derived products from different males interact during sperm competition—from kamikaze sperm to sperm incapacitation—remains controversial. Repeated matings in the parasitoid wasp Nasonia vitripennis lead to a short-term reduction of efficient sperm use by females, which is crucial for a haplodiploid organism when needing to allocate sex adaptively (i.e. by fertilizing eggs to produce daughters). Repeated matings by females in this species, therefore, constrain sex allocation through this “sperm-blocking” effect, eliciting a cost to polyandry. Here, we explore the causes and consequences of sperm blocking and test the hypothesis that it is an ejaculate-related trait associated with sperm competition. First, we show that sperm blocking, which leads to an overproduction of sons, is not correlated with success in either offensive or defensive roles in sperm competition. Then, we show that the extent of sperm blocking is not affected by self–self or kin–kin ejaculate interactions when compared to self vs nonself or kin versus nonkin sperm competition. Our results suggest that sperm blocking is not a sperm competition adaptation, but is instead associated with the mechanics of processing sperm in this species, which are likely shaped by selection on female reproductive morphology for adaptive sex allocation.PostprintPeer reviewe

    The ITGAV rs3738919 variant and susceptibility to rheumatoid arthritis in four Caucasian sample sets

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    INTRODUCTION: Angiogenesis is an important process in the development of destructive synovial pannus in rheumatoid arthritis (RA). The ITGAV +gene encodes a cell cycle-associated antigen, integrin alphanubeta 3, which plays a role in RA angiogenesis. Previously, two independent studies identified an association between the major allele of the ITGAV single-nucleotide polymorphism (SNP) rs3738919 and RA. We therefore tested this association in an independent study using New Zealand (NZ) and Oxford (UK) RA case control samples. METHODS: We compared genotype frequencies in 740 NZ Caucasian RA patients and 553 controls genotyped for rs3738919, using a polymerase chain reaction-restriction fragment length polymorphism assay. A TaqMan genotyping SNP assay was used to type 713 Caucasian RA patients and 515 control samples from Oxford for the rs3738919 variant. Association of rs3738919 with RA was tested in these two sample sets using the chi-square goodness-of-fit test. The Mantel-Haenszel test was used to perform a meta-analysis, combining the genetic results from four independent Caucasian case control cohorts, consisting of 3,527 cases and 4,126 controls. Haplotype analysis was also performed using SNPs rs3911238, rs10174098 and rs3738919 in the Wellcome Trust Case Control Consortium, NZ and Oxford case control samples. RESULTS: We found no evidence for association between ITGAV and RA in either the NZ or Oxford sample set (odds ratio [OR] = 0.88, P(allelic) = 0.11 and OR = 1.18, P(allelic) = 0.07, respectively). Inclusion of these data in a meta-analysis (random effects) of four independent cohorts (3,527 cases and 4,126 controls) weakens support for the hypothesis that rs3738919 plays a role in the development of RA (OR(combined) = 0.92, 95% confidence interval 0.80 to 1.07; P = 0.29). No consistent haplotype associations were evident. CONCLUSIONS: Association of ITGAV SNP rs7378919 with RA was not replicated in NZ or Oxford case control sample sets. Meta-analysis of these and previously published data lends limited support for a role for the ITGAV in RA in Caucasians of European ancestry
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