248 research outputs found
ElectronâDiffraction Study of Ammonia and Deuteroammonia
The gasâphase structures of NH3 and ND3 molecules were determined by the sectorâmicrophotometer method of electron diffraction. The following internuclear distances rgrg and mean amplitudes lele with estimated standard errors were obtained: For NH3, rg(NâââH)â = â1.0302â±â0.002Ă
,rg(HâââH)â = â1.662â±â0.010Ă
,le(NâââH)â = â0.0731â±â0.002Ă
,le(HâââH)â = â0.125â±â0.006Ă
rg(NâH)=1.0302±0.002Ă
,rg(HâH)=1.662±0.010Ă
,le(NâH)=0.0731±0.002Ă
,le(HâH)=0.125±0.006Ă
, and for ND3, rg(NâââD)â = â1.0266â±â0.003Ă
,rg(DâââD)â = â1.654â±â0.008Ă
,le(NâââD)â = â0.0611â±â0.002Ă
,le(DâââD)â = â0.101â±â0.006Ă
rg(NâD)=1.0266±0.003Ă
,rg(DâD)=1.654±0.008Ă
,le(NâD)=0.0611±0.002Ă
,le(DâD)=0.101±0.006Ă
, with the parameter ÎșÎș representing bondâstretching anharmonicity fixed at 1.0âĂâ10â5 and 0.5âĂâ10â5 Ă
3 for NâH and NâD, respectively. Effects of anharmonicity and isotope differences in the structural parameters analogous to those in CH4 and CD4 were observed. The rα0rα0 and rere bond distances calculated from the above rgrg distances are found to be consistent with the corresponding rzrz and rere distances derived from the spectroscopic rotational constants of Benedict and Plyler. The isotope effects reported by Bell and by Halevi for the dipole moment and polarizability of ammonia are discussed briefly in the light of the present results.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69943/2/JCPSA6-49-6-2488-1.pd
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The Arctic Predictability and Prediction on Seasonal-to-Interannual TimEscales (APPOSITE) data set version 1
Abstract. Recent decades have seen significant developments in climate prediction capabilities at seasonal-to-interannual timescales. However, until recently the potential of such systems to predict Arctic climate had rarely been assessed. This paper describes a multi-model predictability experiment which was run as part of the Arctic Predictability and Prediction On Seasonal to Interannual Timescales (APPOSITE) project. The main goal of APPOSITE was to quantify the timescales on which Arctic climate is predictable. In order to achieve this, a coordinated set of idealised initial-value predictability experiments, with seven general circulation models, was conducted. This was the first model intercomparison project designed to quantify the predictability of Arctic climate on seasonal to interannual timescales. Here we present a description of the archived data set (which is available at the British Atmospheric Data Centre), an assessment of Arctic sea ice extent and volume predictability estimates in these models, and an investigation into to what extent predictability is dependent on the initial state. The inclusion of additional models expands the range of sea ice volume and extent predictability estimates, demonstrating that there is model diversity in the potential to make seasonal-to-interannual timescale predictions. We also investigate whether sea ice forecasts started from extreme high and low sea ice initial states exhibit higher levels of potential predictability than forecasts started from close to the models' mean state, and find that the result depends on the metric. Although designed to address Arctic predictability, we describe the archived data here so that others can use this data set to assess the predictability of other regions and modes of climate variability on these timescales, such as the El NiñoâSouthern Oscillation
Reader and author gender and genre in Goodreads
This is an accepted manuscript of an article published by SAGE Publishing in Journal of Librarianship & Information Science on 01/05/2017, available online: https://doi.org/10.1177/0961000617709061
The accepted version of the publication may differ from the final published version.There are known gender differences in book preferences in terms of both genre and author gender but their extent and causes are not well understood. It is unclear whether reader preferences for author genders occur within any or all genres and whether readers evaluate books differently based on author genders within specific genres. This article exploits a major source of informal book reviews, the Goodreads.com website, to assess the influence of reader and author genders on book evaluations within genres. It uses a quantitative analysis of 201,560 books and their reviews, focusing on the top 50 user-specified genres. The results show strong gender differences in the ratings given by reviewers to books within genres, such as female reviewers rating contemporary romance more highly, with males preferring short stories. For most common book genres, reviewers give higher ratings to books authored by their own gender, confirming that gender bias is not confined to the literary elite. The main exception is the comic book, for which male reviewers prefer female authors, despite their scarcity. A word frequency analysis suggested that authors wrote, and reviewers valued, gendered aspects of books within a genre. For example, relationships and romance were disproportionately mentioned by women in mystery and fantasy novels. These results show that, perhaps for the first time, it is possible to get large scale evidence about the reception of books by typical readers, if they post reviews online
Reviewing, indicating, and counting books for modern research evaluation systems
In this chapter, we focus on the specialists who have helped to improve the
conditions for book assessments in research evaluation exercises, with
empirically based data and insights supporting their greater integration. Our
review highlights the research carried out by four types of expert communities,
referred to as the monitors, the subject classifiers, the indexers and the
indicator constructionists. Many challenges lie ahead for scholars affiliated
with these communities, particularly the latter three. By acknowledging their
unique, yet interrelated roles, we show where the greatest potential is for
both quantitative and qualitative indicator advancements in book-inclusive
evaluation systems.Comment: Forthcoming in Glanzel, W., Moed, H.F., Schmoch U., Thelwall, M.
(2018). Springer Handbook of Science and Technology Indicators. Springer Some
corrections made in subsection 'Publisher prestige or quality
The High-Resolution Coronal Imager, Flight 2.1
The third flight of the High-Resolution Coronal Imager (Hi-Câ2.1) occurred on May 29, 2018; the Sounding Rocket was launched from White Sands Missile Range in New Mexico. The instrument has been modified from its original configuration (Hi-Câ1) to observe the solar corona in a passband that peaks near 172 Ă
, and uses a new, custom-built low-noise camera. The instrument targeted Active Region 12712, and captured 78 images at a cadence of 4.4 s (18:56:22âââ19:01:57 UT; 5 min and 35 s observing time). The image spatial resolution varies due to quasi-periodic motion blur from the rocket; sharp images contain resolved features of at least 0.47 arcsec. There are coordinated observations from multiple ground- and space-based telescopes providing an unprecedented opportunity to observe the mass and energy coupling between the chromosphere and the corona. Details of the instrument and the data set are presented in this paper
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The 1930s as black mirror: Visions of historical repetition in the global financial press, 2007-2009
Media coverage of the recent financial crisis has referred extensively to various past crises, and in particular to the events of the 1930s. This article suggests that the idea of the Great Depression has effectively come to function as a kind of historical âblack mirrorâ â a quasi-object within which conjuncture and historical representation interact to produce an image of capitalist history itself. Focusing on the journalistic output of four key financial publications, I trace how portrayals of the 1930s have evolved over the course of the crisis. I find that while the 1930s are frequently and consistently invoked in ways that purport to reveal the historicity of the crisis, these representations produce an oscillation between different visions of historical repetition, which in turn underpin competing interpretations of the crisis as it unfolds. In so doing, I argue, appeals to the 1930s have simultaneously served to conceal and disclose the constitutive relation of historical imagination to historical process â a double move that has had the paradoxical effect of both securing and undermining the reproduction of finance capitalism as we have come to know it
Unworking Milton: Steps to a Georgics of the Mind
Traditionally read as a poem about laboring subjects who gain power through abstract and abstracting forms of bodily discipline, John Miltonâs Paradise Lost (1667, 1674) more compellingly foregrounds the erotics of the Garden as a space where humans and nonhumans intra-act materially and sexually. Following Christopher Hill, who long ago pointed to not one but two revolutions in the history of seventeenth-century English radicalismâthe first, âthe one which succeeded[,] . . . the protestant ethicâ; and the second, âthe revolution which never happened,â which sought âcommunal property, a far wider democracy[,] and rejected the protestant ethicââI show how Miltonâs Paradise Lost gives substance to âthe revolution which never happenedâ by imagining a commons, indeed a communism, in which human beings are not at the center of things, but rather constitute one part of the greater ecology of mind within Miltonâs poem. In the space created by this ecological reimagining, plants assume a new agency. I call this reimagining âecology to come.
Parenting Science Gang : radical co-creation of research projects led by parents of young children
Background Parents are increasingly searching online for information supported by research but can find it difficult to identify results relevant to their own experiences. More troublingly, a number of studies indicate that parenting information found online often can be misleading or wrong. The goal of the Parenting Science Gang (PSG) project was to use the power of the Internet to help parents ask questions they wanted to have answered by scientific research and to feel confident in assessing research evidence. Methods By using Facebook to recruit groups and facilitate interactions, PSG was able to engage fully the target public of parents of young children in the radical co-production of scientific studies, while not creating an undue burden on time or restricting participants due to disability, financial status or location. By giving parents true partnership and control of creation of projects, PSG ensured that the chosen questions were ones that were of most relevance and interest to them. Results This paper presents a summary of eight projects, with three in more detail, designed and implemented by PSG Facebook groups in collaboration with experts. Most projects had health related themes, often prompted by dissatisfaction with treatment of parents by health professionals or by feelings of being marginalised by pregnancy and motherhood, as well as by the lack of evidence for their questions and concerns. The PSG approach meant that these frustrations were channelled into actions. All eight of the PSG groups engaged in meaningful interactions with experts and co-produced studies with the groups defining the questions of interest. Conclusions This radically user-led design meant that the PSG staff and the collaborating experts had to live with a high degree of uncertainty. Nevertheless, PSG achieved its goal of academically productive, truly co-produced projects, but as important were the positive effects it had on many of the participants, both parents and experts. At the point of writing this paper, PSG projects have led to outputs including at least eight papers published, in press or in preparation, seven conference presentations, testimony to the Infant Feeding All-Party Parliamentary Group, and with more to come
The general fault in our fault lines
Pervading global narratives suggest that political polarization is increasing, yet the accuracy of such group meta-perceptions has been drawn into question. A recent US study suggests that these beliefs are inaccurate and drive polarized beliefs about out-groups. However, it also found that informing people of inaccuracies reduces those negative beliefs. In this work, we explore whether these results generalize to other countries. To achieve this, we replicate two of the original experiments with 10,207 participants across 26 countries. We focus on local group divisions, which we refer to as fault lines. We find broad generalizability for both inaccurate meta-perceptions and reduced negative motive attribution through a simple disclosure intervention. We conclude that inaccurate and negative group meta-perceptions are exhibited in myriad contexts and that informing individuals of their misperceptions can yield positive benefits for intergroup relations. Such generalizability highlights a robust phenomenon with implications for political discourse worldwide
A Tale of Four âCarpâ: Invasion Potential and Ecological Niche Modeling
. We assessed the geographic potential of four Eurasian cyprinid fishes (common carp, tench, grass carp, black carp) as invaders in North America via ecological niche modeling (ENM). These âcarpâ represent four stages of invasion of the continent (a long-established invader with a wide distribution, a long-established invader with a limited distribution, a spreading invader whose distribution is expanding, and a newly introduced potential invader that is not yet established), and as such illustrate the progressive reduction of distributional disequilibrium over the history of species' invasions.We used ENM to estimate the potential distributional area for each species in North America using models based on native range distribution data. Environmental data layers for native and introduced ranges were imported from state, national, and international climate and environmental databases. Models were evaluated using independent validation data on native and invaded areas. We calculated omission error for the independent validation data for each species: all native range tests were highly successful (all omission values <7%); invaded-range predictions were predictive for common and grass carp (omission values 8.8 and 19.8%, respectively). Model omission was high for introduced tench populations (54.7%), but the model correctly identified some areas where the species has been successful; distributional predictions for black carp show that large portions of eastern North America are at risk.ENMs predicted potential ranges of carp species accurately even in regions where the species have not been present until recently. ENM can forecast species' potential geographic ranges with reasonable precision and within the short screening time required by proposed U.S. invasive species legislation
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