1,129 research outputs found
Large-Area Liquid Scintillation Detector Slab
A low-cost detector 18' x 2' x 5" has been developed for an underground cosmic ray neutrino experiment. The liquid employed is a high-clarity mineral oil-based mixture, and light is guided to the ends of the detector by total internal reflection at the surface of the Lucite container. Signals from 2 five-inch photomultipliers at each end give energy and event location for single penetrating particles, with relatively good discrimination against natural radioactivity by virtue of the substantial thickness. Data are presented on the response function of the tank, energy resolution, rates and thresholds. A number of modifications that have been tried are also described
Who is to blame? The relationship between ingroup identification and relative deprivation is moderated by ingroup attributions
Contradictory evidence can be found in the literature about whether ingroup identification and perceived relative deprivation are positively or negatively related. Indeed, theoretical arguments can be made for both effects. It was proposed that the contradictory findings can be explained by considering a hitherto unstudied moderator: The extent to which deprivation is attributed to the ingroup. It was hypothesised that identification would only have a negative impact on deprivation, and that deprivation would only have a negative impact on identification, if ingroup attributions are high. To test this, attributions to the ingroup were experimentally manipulated among British student participants (N = 189) who were asked about their perceived deprivation vis-à-vis German students, yield ing support for the hypotheses
Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).
Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (Müller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed
Satisfaction with democracy and voter turnout
Numerous studies conclude that countries in which citizens express higher levels of satisfaction with democracy also tend to display higher levels of voter turnout in national elections. Yet it is difficult to draw causal inferences from this positive cross-sectional relationship, because democracies feature many historical, cultural, and institutional differences that are not easily controlled for in cross-sectional comparisons. We apply an alternative, temporal approach to this issue by asking the question: Are over-time declines (increases) in aggregate levels of satisfaction within democracies associated with increases (declines) in levels of voter turnout within these democracies? Our temporal analysis of this relationship in 12 democracies over the period 1976–2011 reveals a pattern that is the opposite of that suggested by previous cross-sectional studies: namely, we find that over-time increases in citizens’ satisfaction with democracy are associated with significant decreases in voter turnout in national elections in these countries. </jats:p
When the going gets tough, the tough get going: Social identification and individual effort in intergroup competition.
Based on social identity theory, the authors predicted that in ongoing intergroup competition, people’s strength of social identification will have a positive impact on their behavioral efforts on behalf of an ingroup when its current status is low, whereas this will not be the case when its current status is high. In a first experiment, male participants showed the expected pattern of behavior. Female participants, however, tended to display opposite reactions. As a possible explanation, it was argued that the experimental procedure may have inadvertently evoked a gender-based stereotype threat for female participants. In an attempt to obtain more consistent support for their hypothesis, the authors therefore replicated the experiment with modifications to avoid such a threat. These changes proved to be effective in the sense that this time the predicted interaction effect between ingroup identification and current group status was obtained for both male and female participants
Large-Area Liquid Scintillation Detector Slab
A low-cost detector 18' x 2' x 5" has been developed for an underground cosmic ray neutrino experiment. The liquid employed is a high-clarity mineral oil-based mixture, and light is guided to the ends of the detector by total internal reflection at the surface of the Lucite container. Signals from 2 five-inch photomultipliers at each end give energy and event location for single penetrating particles, with relatively good discrimination against natural radioactivity by virtue of the substantial thickness. Data are presented on the response function of the tank, energy resolution, rates and thresholds. A number of modifications that have been tried are also described
Fungal entomopathogens: new insights on their ecology
An important mechanism for insect pest control should be the use of fungal entomopathogens. Even though these organisms have been studied for more than 100 y, their effective use in the field remains elusive. Recently, however, it has been discovered that many of these entomopathogenic fungi play additional roles in nature. They are endophytes, antagonists of plant pathogens, associates with the rhizosphere, and possibly even plant growth promoting agents. These findings indicate that the ecological role of these fungi in the environment is not fully understood and limits our ability to employ them successfully for pest management. In this paper, we review the recently discovered roles played by many entomopathogenic fungi and propose new research strategies focused on alternate uses for these fungi. It seems likely that these agents can be used in multiple roles in protecting plants from pests and diseases and at the same time promoting plant growth
Genome-wide characterization and expression profiling of immune genes in the diamondback moth, Plutella xylostella (L.)
The diamondback moth, Plutella xylostella (L.), is a destructive pest that attacks cruciferous crops worldwide. Immune responses are important for interactions between insects and pathogens and information on these underpins the development of strategies for biocontrol-based pest management. Little, however, is known about immune genes and their regulation patterns in P. xylostella. A total of 149 immune-related genes in 20 gene families were identified through comparison of P. xylostella genome with the genomes of other insects. Complete and conserved Toll, IMD and JAK-STAT signaling pathways were found in P. xylostella. Genes involved in pathogen recognition were expanded and more diversified than genes associated with intracellular signal transduction. Gene expression profiles showed that the IMD pathway may regulate expression of antimicrobial peptide (AMP) genes in the midgut, and be related to an observed down-regulation of AMPs in experimental lines of insecticide-resistant P. xylostella. A bacterial feeding study demonstrated that P. xylostella could activate different AMPs in response to bacterial infection. This study has established a framework of comprehensive expression profiles that highlight cues for immune regulation in a major pest. Our work provides a foundation for further studies on the functions of P. xylostella immune genes and mechanisms of innate immunity.Xiaofeng Xia, Liying Yu, Minqian Xue, Xiaoqiang Yu, Liette Vasseur, Geoff M. Gurr, Simon W. Baxter, Hailan Lin, Junhan Lin, Minsheng Yo
Threats posed by the fungal kingdom to humans, wildlife, and agriculture
The fungal kingdom includes at least 6 million eukaryotic species and is remarkable with respect to its profound impact on global health, biodiversity, ecology, agriculture, manufacturing, and biomedical research. Approximately 625 fungal species have been reported to infect vertebrates, 200 of which can be human associated, either as commensals and members of our microbiome or as pathogens that cause infectious diseases. These organisms pose a growing threat to human health with the global increase in the incidence of invasive fungal infections, prevalence of fungal allergy, and the evolution of fungal pathogens resistant to some or all current classes of antifungals. More broadly, there has been an unprecedented and worldwide emergence of fungal pathogens affecting animal and plant biodiversity. Approximately 8,000 species of fungi and Oomycetes are associated with plant disease. Indeed, across agriculture, such fungal diseases of plants include new devastating epidemics of trees and jeopardize food security worldwide by causing epidemics in staple and commodity crops that feed billions. Further, ingestion of mycotoxins contributes to ill health and causes cancer. Coordinated international research efforts, enhanced technology translation, and greater policy outreach by scientists are needed to more fully understand the biology and drivers that underlie the emergence of fungal diseases and to mitigate against their impacts. Here, we focus on poignant examples of emerging fungal threats in each of three areas: human health, wildlife biodiversity, and food security
Indigenous identity, natural resources, and contentious politics in Bolivia: a disaggregated conflict analysis; 2000-2011
How do natural resources and ethnic identity interact to incite or to mitigate
social conflict? This article argues that high-value natural resources can act as an
important catalyst for the politicization of ethnic, specifically indigenous identity,
and contribute to social conflict as they limit the malleability of identity frames
and raise the stakes of confrontations. We test this argument using unique subnational
data from Bolivian provinces. Drawing on Bolivian newspaper reports,
we code conflict events for all of the 112 provinces from 2000 to 2011. We
join this conflict data with information on local ethnic composition from the
census, the political representation of ethnic groups at the national level, as well
as geo-spatial information on gas deposits. Using time-series cross-sectional
count models, we show a significant conflict-promoting effect of the share of
indigenous people in provinces with gas reserves, but not without
- …