4,686 research outputs found
Resource-Efficient Chemistry on Quantum Computers with the Variational Quantum Eigensolver and the Double Unitary Coupled-Cluster Approach.
Applications of quantum simulation algorithms to obtain electronic energies of molecules on noisy intermediate-scale quantum (NISQ) devices require careful consideration of resources describing the complex electron correlation effects. In modeling second-quantized problems, the biggest challenge confronted is that the number of qubits scales linearly with the size of the molecular basis. This poses a significant limitation on the size of the basis sets and the number of correlated electrons included in quantum simulations of chemical processes. To address this issue and enable more realistic simulations on NISQ computers, we employ the double unitary coupled-cluster (DUCC) method to effectively downfold correlation effects into the reduced-size orbital space, commonly referred to as the active space. Using downfolding techniques, we demonstrate that properly constructed effective Hamiltonians can capture the effect of the whole orbital space in small-size active spaces. Combining the downfolding preprocessing technique with the variational quantum eigensolver, we solve for the ground-state energy of H2, Li2, and BeH2 in the cc-pVTZ basis using the DUCC-reduced active spaces. We compare these results to full configuration-interaction and high-level coupled-cluster reference calculations
Maternal antibodies from mothers of children with autism alter brain growth and social behavior development in the rhesus monkey.
Antibodies directed against fetal brain proteins of 37 and 73 kDa molecular weight are found in approximately 12% of mothers who have children with autism spectrum disorder (ASD), but not in mothers of typically developing children. This finding has raised the possibility that these immunoglobulin G (IgG) class antibodies cross the placenta during pregnancy and impact brain development, leading to one form of ASD. We evaluated the pathogenic potential of these antibodies by using a nonhuman primate model. IgG was isolated from mothers of children with ASD (IgG-ASD) and of typically developing children (IgG-CON). The purified IgG was administered to two groups of female rhesus monkeys (IgG-ASD; n=8 and IgG-CON; n=8) during the first and second trimesters of pregnancy. Another control group of pregnant monkeys (n=8) was untreated. Brain and behavioral development of the offspring were assessed for 2 years. Behavioral differences were first detected when the macaque mothers responded to their IgG-ASD offspring with heightened protectiveness during early development. As they matured, IgG-ASD offspring consistently deviated from species-typical social norms by more frequently approaching familiar peers. The increased approach was not reciprocated and did not lead to sustained social interactions. Even more striking, IgG-ASD offspring displayed inappropriate approach behavior to unfamiliar peers, clearly deviating from normal macaque social behavior. Longitudinal magnetic resonance imaging analyses revealed that male IgG-ASD offspring had enlarged brain volume compared with controls. White matter volume increases appeared to be driving the brain differences in the IgG-ASD offspring and these differences were most pronounced in the frontal lobes
Creativity out of chaos
Creativity is said to be highly desired in post-modern and post-industrial organizations Creativity and anarchy on the one hand, and managerialism, on the other, can be seen as different forms of knowledge, two opposed ideals. In many organizational as well as societal reforms we currently observe it is the managerialist ideal that wins over the anarchic. In this paper, we wonder if people fear anarchy? We reflect on the possible reasons for the fear, and we also try to explain why we believe that anarchic organizing should not be avoided or feared
Physical activity mass media campaigns and their evaluation: a systematic review of the literature 2003–2010
Internationally, mass media campaigns to promote regular moderate-intensity physical activity have increased recently. Evidence of mass media campaign effectiveness exists in other health areas, however the evidence for physical activity is limited. The purpose was to systematically review the literature on physical activity mass media campaigns, 2003–2010. A focus was on reviewing evaluation designs, theory used, formative evaluation, campaign effects and outcomes. Literature was searched resulting in 18 individual adult mass media campaigns, mostly in high-income regions and two in middle-income regions. Designs included: quasi experimental (n = 5); non experimental (n = 12); a mixed methods design (n = 1). One half used formative research. Awareness levels ranged from 17 to 95%. Seven campaigns reported significant increases in physical activity levels. The review found that beyond awareness raising, changes in other outcomes were measured, assessed but reported in varying ways. It highlighted improvements in evaluation, although limited evidence of campaign effects remain. It provides an update on the evaluation methodologies used in the adult literature. We recommend optimal evaluation design should include: (1) formative research to inform theories/frameworks, campaign content and evaluation design; (2) cohort study design with multiple data collection points; (3) sufficient duration; (4) use of validated measures; (5) sufficient evaluation resources
Robots and cyborgs: to be or to have a body?
Starting with service robotics and industrial robotics, this paper aims to suggest philosophical reflections about the relationship between body and machine, between man and technology in our contemporary world. From the massive use of the cell phone to the robots which apparently “feel” and show emotions like humans do. From the wearable exoskeleton to the prototype reproducing the artificial sense of touch, technological progress explodes to the extent of embodying itself in our nakedness. Robotics, indeed, is inspired by biology in order to develop a new kind of technology affecting human life. This is a bio-robotic approach, which is fulfilled in the figure of the cyborg and consequently in the loss of human nature. Today, humans have reached the possibility to modify and create their own body following their personal desires. But what is the limit of this achievement? For this reason, we all must question ourselves whether we have or whether we are a body
Rewriting Modernity
This article rereads Paul Virilio, drawing on the distinctionbetween topography and topology to argue a case for Virilio as a rewriter of modernity. Invoking Jean-François Lyotard’s notion of rewriting modernity as an unbroken process of accumulation founded on affective life in “Re-writing Modernity” and “Argumentation and Presentation: The Foundation Crisis,” it enlists topology as a horizontal spatial structure that enables us to rethink space, time,and modernity outside the limits of the “squared horizon,” where the“squared horizon” is viewed as a spatial and textual metaphor for framing perspectives on the past, present, and future. The analysis deconstructs the topography of the “squared horizon” as a relationality in an unfolding continuum, where spaces exist ontologically and where the immaterial forces of the dromospheric and the atmospheric generate a relational and historical connectedness
Use of early lactation milk recording data to predict the calving to conception interval in dairy herds
Economic success in dairy herds is heavily reliant on obtaining pregnancies at an early stage of lactation. Our objective in this study was to attempt to predict the likelihood of conception occurring by d 100 and 150 of lactation (days in milk, DIM) by Markov chain Monte Carlo analysis using test day milk recording data and reproductive records gathered retrospectively from 8,750 cows from 33 dairy herds located in the United Kingdom. Overall, 65% of cows recalved with 30, 46, and 65% of cows conceiving by 100 DIM, 150 DIM, and beyond 150 DIM, respectively. Overall conception rate (total cows pregnant/total number of inseminations) was 27.47%. Median and mean calving to conception intervals were 123 and 105 d, respectively. The probability of conception by both 100 DIM and 150 DIM was positively associated with the average daily milk weight produced during the fourth week of lactation (W4MK) and protein percentage for test day samples collected between 0 to 30 and 31 to 60 DIM. Butterfat percentage at 0 to 30 DIM was negatively associated with the probability of conception by 100 DIM but not at 150 DIM. High somatic cell count (SCC) at both 0 to 30 and 31 to 60 DIM was negatively associated with the probability of conception by 100 DIM, whereas high SCC at 31 to 60 DIM was associated with a reduced probability of conception by 150 DIM. Increasing parity was associated with a reduced odds of pregnancy. Posterior predictions of the likelihood of conception for cows categorized as having “good” (W4MK >30 kg and protein percentage at 0 to 30 and 31 to 60 DIM >3.2%) or “poor” (W4MK <25 kg and protein percentage at 0 to 30 and 31 to 60 DIM <3.0%) early lactation attributes with actual observed values indicated model fit was good. The predicted likelihood of a “good” cow conceiving by 100 and 150 DIM was 0.39 and 0.57, respectively (actual observed values 0.40 and 0.59). The corresponding values for a “poor” cow were 0.28 and 0.42 (actual observed values 0.26 and 0.37). Predictions of the future reproductive success of cows may be possible using a limited number of early lactation attributes
Chemical behavior of the Dwarf Irregular Galaxy NGC 6822. Its PN and HII region abundances
We aim to derive the chemical behavior of a significant sample of PNe and HII
regions in the irregular galaxy NGC 6822 The selected objects are distributed
in different zones of the galaxy. Due to the faintness of PNe and HII regions
in NGC 6822, to gather spectroscopic data with large telescopes is necessary.
We obtained a well suited sample of spectra by employing VLT-FORS 2 and
Gemini-GMOS spectrographs. Ionic and total abundances are calculated for the
objects where electron temperatures can be determined through the detection of
[OIII] \lambda 4363 or/and [NII] \lambda 5755 lines. A "simple" chemical
evolution model has been developed and the observed data are used to compute a
model for NGC 6822 in order to infer a preliminary chemical history in this
galaxy. Confident determinations of He, O, N, Ne, S and Ar abundances were
derived for a sample of 11 PNe and one HII region. We confirm that the present
ISM is chemically homogeneous, at least in the central 2 kpc of the galaxy,
showing a value 12+log O/H = 8.060.04. From the abundance pattern of PNe,
we identified two populations: a group of young PNe with abundances similar to
HII regions and a group of older objects with abundances a factor of two lower.
A couple of extreme Type I PNe were found. No third dredge-up O enrichement was
detected in PNe of this galaxy. The abundance determinations allow us to
discuss the chemical behavior of the present and past ISM in NGC 6822. Our
preliminary chemical evolution model predicts that an important gas-mass lost
occurred during the first 5.3 Gyr, that no star higher than 40 M was
formed, and that 1% of all 3-15 M stars became binary systems
progenitors to SNIa.Comment: 15 pages, 3 figures and 4 tables. A&A, Accepted 13/06/200
Empirical Challenges in Organizational Aesthetics Research: Towards a Sensual Methodology
Despite growing scholarly interest in aesthetic dimensions of organizational life, there is a lack of literature expressly engaging with the methodological mechanics of 'doing aesthetics research'. This article addresses that gap. It begins with an overview of the conceptual idiosyncrasies of 'aesthetics' as a facet of human existence and maps out the challenges these pose for empirical research methodology. A review of methodological approaches adopted to date in empirical studies of organizational aesthetics is then presented. The remainder of the article draws on the author's experiences and suggests methods and techniques to address both conceptual and practical challenges encountered during the execution of an organizational aesthetics research project. The article calls for a firmer focus on the aesthetic experiences of organizational members in addition to those of researchers and concludes with some suggestions as to the future of such 'sensual methodologies' </jats:p
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