2,567 research outputs found
The inner automorphism 3-group of a strict 2-group
Any group gives rise to a 2-group of inner automorphisms,
. It is an old result by Segal that the nerve of this is the
universal -bundle. We discuss that, similarly, for every 2-group
there is a 3-group and a slightly smaller 3-group
of inner automorphisms. We describe these for
any strict 2-group, discuss how can be
understood as arising from the mapping cone of the identity on and
show that its underlying 2-groupoid structure fits into a short exact sequence
.
As a consequence, encodes the properties of the
universal 2-bundle.Comment: references added, relation to simplicial constructions expanded,
version to appear in JHR
The Voluntary Carbon Market and Business Innovation for Sustainable Development
There is no need to choose between preventing climate change and promoting economic growth and development. In fact, many sources now agree that responding to climate change will create significant business opportunities. This paper examines the role that one of those opportunities—the voluntary carbon market—plays in helping business grow sustainably and in promoting innovation. Carbon markets and credits, which are an increasingly popular way of limiting the quantity of greenhouse gas emissions, are a great example of an effective climate change response with potential business implications. While the world of carbon markets is increasingly uncertain, the voluntary market remains a source of growth and innovation. The three cases examined here showcase different traits and capabilities of the voluntary carbon market (VCM). We learn that the VCM is capable of supporting small businesses with unique business models in Africa, of helping large businesses achieve corporate social responsibility (CSR) goals in the United States, and of promoting conservation and increasing the value of ecosystem services in Peru. The VCM is thus an important resource for promoting sustainable development across the globe and is a powerful complement to existing mandatory carbon markets
CONSUMERS' VALUATION OF INSECTICIDE USE RESTRICTIONS: AN APPLICATION TO APPLES
Economic assessments of pesticide regulations typically focus on producer impacts and generally ignore possible changes in product demand. These changes may be nonnegligible if real and/or perceived product attributes change. We measure consumersÂ’' willingness to pay (WTP) for the elimination of one insecticide and also a whole group of insecticides in apple production using a multiple-round Vickrey auction. The data are analyzed using nonparametric statistical tests and a double-hurdle model. Our findings show that consumer perceptions of product attributes change if pesticides are removed from production, and this is reflected in WTP changes. WTP is shown to be income elastic.Consumer/Household Economics, Crop Production/Industries,
Nonlinear denoising of transient signals with application to event related potentials
We present a new wavelet based method for the denoising of {\it event related
potentials} ERPs), employing techniques recently developed for the paradigm of
deterministic chaotic systems. The denoising scheme has been constructed to be
appropriate for short and transient time sequences using circular state space
embedding. Its effectiveness was successfully tested on simulated signals as
well as on ERPs recorded from within a human brain. The method enables the
study of individual ERPs against strong ongoing brain electrical activity.Comment: 16 pages, Postscript, 6 figures, Physica D in pres
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Bleeding changes after levonorgestrel 52-mg intrauterine system insertion for contraception in women with self-reported heavy menstrual bleeding.
BackgroundThe levonorgestrel 52-mg intrauterine system has proven efficacy for heavy menstrual bleeding treatment in clinical trials, but few data exist to demonstrate how rapidly the effects occur and the effects in women with self-reported heavy bleeding, as seen commonly in clinical practice.ObjectiveEvaluate changes in bleeding patterns in women with self-reported heavy menstrual bleeding before levonorgestrel 52-mg intrauterine system insertion.Study designA total of 1714 women aged 16-45 years old received a levonorgestrel 52-mg intrauterine system in a multicenter trial evaluating contraceptive efficacy and safety for up to 10 years. At screening, participants described their baseline menstrual bleeding patterns for the previous 3 months. Participants completed daily diaries with subjective evaluation of bleeding information for the first 2 years. For this analysis, we included women with at least 1 complete 28-day cycle of intrauterine system use and excluded women using a hormonal or copper intrauterine contraception in the month prior to study enrollment. We evaluated changes in menstrual bleeding and discontinuation for bleeding complaints per 28-day cycle over 26 cycles (2 years) in women who self-reported their baseline pattern as heavy. We also compared rates of amenorrhea, defined as no bleeding or spotting, within the entire study population in women with subjective heavy menstrual bleeding at baseline compared with those who did not complain of heavy menstrual bleeding.ResultsOf the 1513 women in this analysis, 150 (9.9%) reported baseline heavy menstrual bleeding. The majority of women reported no longer experiencing heavy menstrual bleeding by the end of cycle 1 (112/150, 74.7%) with even greater rates by cycle 2 (124/148, 83.8%). At the end of cycles 6, 13, and 26, 129 of 140 (92.1%; 95% confidence interval, 87.7%-96.6%), 114 of 123 (92.7%; 95% confidence interval, 88.1%-97.3%), and 100 of 103 (97.1%; 95% confidence interval, 93.8%-100%) women reported no heavy menstrual bleeding, respectively. After cycles 13 and 26, 63 of 123 (51.2%; 95% confidence interval, 42.4%-60.1%) and 66 of 103 (64.1%; 95% confidence interval, 54.8%-73.3%), respectively, reported their bleeding as amenorrhea or spotting only. A lower proportion of women with baseline self-reported heavy menstrual bleeding reported amenorrhea as compared with women in the overall study cohort without heavy menstrual bleeding at the end of 6 cycles (319 [25.5%] vs 21 [15.0%], P=.005) and 13 cycles (382 [34.4%] vs 26 [21.1%], P=.003); differences were not significant after 19 cycles (367 [37.2%] vs 36 [31.0%], P=.022) and 26 cycles (383 [43.5%] vs 38 [36.9%], P=.21). Only 4 (2.7%) women with baseline heavy menstrual bleeding discontinued for bleeding complaints (2 for heavy menstrual bleeding and 2 for irregular bleeding), all within the first year.ConclusionMost women who self-report heavy menstrual bleeding experience significant improvement quickly after levonorgestrel 52-mg intrauterine system insertion. Discontinuation for bleeding complaints among women with baseline heavy menstrual bleeding is very low
An investigation of influences on strategic decision-making in popular recorded music industry micro-enterprises
This thesis investigates the strategic decision-making practices (SDM) in music industry micro-enterprises in the United States. Although a significant body of literature has examined the SDM processes in high-tech firms, manufacturers and other specialty industries, very little has been learned about strategic decision-making within the music industry. Eight cases were used to look at what influences the decision-making practice, and how. Two decisions from each of four firms that are directly involved in the marketing and promotion of recorded music product were chosen. The primary source data came from forty-three interviews by thirty-six respondents from firms that were directly involved in the decision-making practice. Direct observation and note taking on company culture and employee interaction, analysis of artefacts in the form of company emails, websites, social media sites and magazines, and other items referenced in the interviews were also used as data sources.
Bourdieu’s theory of practice was used to conceptualise the decision-making as interplay between social, cultural, symbolic and economic capital, habitus, and field. The principle argument developed in this thesis is consistent with Bourdieu’s concept of recognition, and explores the desire for actors in this field to make strategic decisions that will position themselves better to either acquire and/or use capital that will lead to further power and positioning within the field. The primary practice was often dictated by the actor’s concern for reputation and how other individuals perceived them and their respective firms. Instances of explicit and implicit exploitation of objectified symbolic capital were seen as a necessary practice to achieving firm objectives. This research also incorporates previous research on strategic decision-making in other micro-enterprises, including the use of past experiences, personal biases, heuristics and intuitive behaviours, as they are a product of the relationship between the habitus, capital and field. A Bourdieusian lens allowed for the surfacing of the complex reflexive interplay among Bourdieu’s practice theory and the theoretical constructs of strategic decision-making, which led to a deep description of the influences on these practices in music industry micro-enterprises while further developing his ideas about the field of cultural production. By bringing both of these nuances to the forefront, my analysis leads to a contribution to the decision-making literature for micro-enterprises and music industry theorists while arguing for a repositioning of the popular music industry within the large-scale production of culture, as one characterised by high amounts of symbolic capital, not low amounts as Bourdieu (1996) contends. In addition, I will argue that in order to transform one capital to another, for example, social or economic capital into symbolic capital, there is a need for a field-specific capital. In this case, ‘music industry capital’ is used as a negotiating aid when agents vie for power and positioning within the music industry
Fundamental weight systems are quantum states
Weight systems on chord diagrams play a central role in knot theory and
Chern-Simons theory; and more recently in stringy quantum gravity. We highlight
that the noncommutative algebra of horizontal chord diagrams is canonically a
star-algebra, and ask which weight systems are positive with respect to this
structure; hence we ask: Which weight systems are quantum states, if horizontal
chord diagrams are quantum observables? We observe that the fundamental
gl(n)-weight systems on horizontal chord diagrams with N strands may be
identified with the Cayley distance kernel at inverse temperature beta=ln(n) on
the symmetric group on N elements. In contrast to related kernels like the
Mallows kernel, the positivity of the Cayley distance kernel had remained open.
We characterize its phases of indefinite, semi-definite and definite
positivity, in dependence of the inverse temperature beta; and we prove that
the Cayley distance kernel is positive (semi-)definite at beta=ln(n) for all
n=1,2,3,... In particular, this proves that all fundamental gl(n)-weight
systems are quantum states, and hence so are all their convex combinations. We
close with briefly recalling how, under our "Hypothesis H", this result impacts
on the identification of bound states of multiple M5-branes.Comment: 21 pages; 1 figure; v2: bound sharpene
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