32151 research outputs found
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Nevola, Fabrizio, David Rosenthal, Sharon Strocchia, Nicholas Terpstra, Colin Rose, Julia Rombough, Daniel Jamison, and François Penz, project creators. Hidden Florence. Other.
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The internationalization of hidden champions from Germany and the UK : an extension to the Born-Again Global path
Get PDFAlthough internationalization has been extensively studied, the majority of analyses have focused on motives and enablers, also known as triggers, with less attention paid to internationalization paths. To add to the internationalization paths debate, we explore global niche players dubbed as Hidden Champions from Germany and Britain. Our findings show that a large portion of these firms experience an international ‘rebirth’ by adopting a more accelerated approach to internationalization after already gaining first international experience. This is mainly through exporting activity, which is a variation of the Born-Again Global phenomenon. Due to their unique internationalization path, we call these firms Re-Born-Again Globals. Furthermore, we uncover the critical incidents for the internationalization of these firms, namely changes in management, technology advances, and product diversification.Peer reviewe
Efficient methods for fitting nonlinear non-Gaussian state space models of wildlife population dynamics
Get PDFState-space models (SSMs) are a popular and flexible framework for modelling time series due to their ability to separate changes in the underlying state of a system from the noisy observations made on these states. This thesis explores methods for estimating states and model parameters in non-linear and non-Gaussian Bayesian SSMs. We focus on models of wildlife population dynamics, in particular a case study of the UK grey seal population.
Calculation of the likelihood is fundamental to Bayesian analysis, but direct calculation is typically intractable for non-linear non-Gaussian SSMs. We use a class of simulation-based methods, Sequential Monte Carlo (SMC), which build on repeated importance sampling of simulated states to deliver an unbiased estimate of the likelihood. We find that variance of the estimated likelihood can be high and explore techniques for variance reduction.
For parameter inference, we use particle marginal Metropolis-Hastings (PMMH), which embeds the SMC likelihood within a Markov chain Monte Carlo (MCMC) algorithm. Careful balance is needed between computational effort expended on the SMC step and the number of MCMC samples.
A much faster alternative is the Kalman filter, designed for linear and Gaussian SSMs. We applied the Kalman filter to an approximation of the seal model. The posterior distribution obtained was often close to the true posterior, while reducing computation time by a factor of 1790.
We show the seal model suffers from identifiability issues which cannot be resolved by increasing the accuracy of the observations or allowing more flexibility in the underlying biological process with random effects. However, estimation of underlying states (i.e., population sizes) is unaffected by these issues.
A reduction in PMMH computation time can be achieved by exploiting the structure of the state model: separately estimating likelihood components in each of the 4 seal regions led to a 5-fold increase in speed."This work was supported by the Engineering and Physical Sciences Research Council, via a Doctoral Training Partnership grant to the University of St Andrews; and by the University of St Andrews (School of Mathematics and Statistics)."--Funding Acknowledgement
Reducing time to discovery : materials and molecular modeling, imaging, informatics, and integration
Get PDFThis work was supported by the KAIST-funded Global Singularity Research Program for 2019 and 2020. J.C.A. acknowledges support from the National Science Foundation under Grant TRIPODS + X:RES-1839234 and the Nano/Human Interfaces Presidential Initiative. S.V.K.’s effort was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division and was performed at the Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences (CNMS), a U.S. Department of Energy, Office of Science User Facility.Multiscale and multimodal imaging of material structures and properties provides solid ground on which materials theory and design can flourish. Recently, KAIST announced 10 flagship research fields, which include KAIST Materials Revolution: Materials and Molecular Modeling, Imaging, Informatics and Integration (M3I3). The M3I3 initiative aims to reduce the time for the discovery, design and development of materials based on elucidating multiscale processing-structure-property relationship and materials hierarchy, which are to be quantified and understood through a combination of machine learning and scientific insights. In this review, we begin by introducing recent progress on related initiatives around the globe, such as the Materials Genome Initiative (U.S.), Materials Informatics (U.S.), the Materials Project (U.S.), the Open Quantum Materials Database (U.S.), Materials Research by Information Integration Initiative (Japan), Novel Materials Discovery (E.U.), the NOMAD repository (E.U.), Materials Scientific Data Sharing Network (China), Vom Materials Zur Innovation (Germany), and Creative Materials Discovery (Korea), and discuss the role of multiscale materials and molecular imaging combined with machine learning in realizing the vision of M3I3. Specifically, microscopies using photons, electrons, and physical probes will be revisited with a focus on the multiscale structural hierarchy, as well as structure-property relationships. Additionally, data mining from the literature combined with machine learning will be shown to be more efficient in finding the future direction of materials structures with improved properties than the classical approach. Examples of materials for applications in energy and information will be reviewed and discussed. A case study on the development of a Ni-Co-Mn cathode materials illustrates M3I3's approach to creating libraries of multiscale structure-property-processing relationships. We end with a future outlook toward recent developments in the field of M3I3.Peer reviewe
Impact of active case-finding for tuberculosis on case-notifications in Blantyre, Malawi : a community-based cluster-randomised trial (SCALE)
Get PDFThis work was funded through ELC's Wellcome fellowship 200901/Z/16/Z. PM was also supported through a Wellcome fellowship: 206575/Z/17/Z.Active case-finding (ACF) for tuberculosis can help find the “missing millions” with undiagnosed tuberculosis. In a cluster-randomised trial, we investigated impact of ACF on case-notifications in Blantyre, Malawi, where ACF has been intensively implemented following 2014 estimates of ~1,000 per 100,000 adults with undiagnosed TB. Following a pre-intervention prevalence survey (May 2019 to March 2020), constrained randomisation allocated neighbourhoods to either door-to-door ACF (sputum microscopy for reported cough >2 weeks) or standard-of-care (SOC). Implementation was interrupted by COVID-19. Cluster-level bacteriologically-confirmed case-notification rate (CNR) ratio within 91 days of ACF was our redefined primary outcome; comparison between arms used Poisson regression with random effects. Secondary outcomes were 91-day CNR ratios comparing all tuberculosis registrations and all non-ACF registrations. Interrupted time series (ITS) analysis of CNRs in the SOC arm examined prevalence survey impact. (ISRCTN11400592). 72 clusters served by 10 study-supported tuberculosis registration centres were randomised to ACF (261,244 adults, 58,944 person-years follow-up) or SOC (256,713 adults, 52,805 person-years). Of 1,192 ACF participants, 13 (1.09%) were smear-positive. Within 91 days, 113 (42 bacteriologically-confirmed) and 108 (33 bacteriologically-confirmed) tuberculosis patients were identified as ACF or SOC cluster residents, respectively. There was no difference by arm, with adjusted 91-day CNR ratios 1.12 (95% CI: 0.61–2.07) for bacteriologically-confirmed tuberculosis; 0.93 (95% CI: 0.68–1.28) for all tuberculosis registrations; and 0.86 (95%CI: 0.63–1.16) for non-ACF (routinely) diagnosed. Of 7,905 ACF and 7,992 SOC pre-intervention survey participants, 12 (0.15%) and 17 (0.21%), respectively, had culture/Xpert-confirmed tuberculosis. ITS analysis showed no survey impact on SOC CNRs. Despite residual undiagnosed tuberculosis of 150 per 100,000 population, there was no increase in tuberculosis notifications from this previously successful approach targeting symptomatic disease, likely due to previous TB ACF and rapid declines in TB burden. In such settings, future ACF should focus on targeted outreach and demand creation, alongside optimised facility-based screening.Peer reviewe
God in the eyes of a refugee : emic perspectives on religion and resettlement of Syrian Muslims in North East Scotland
Get PDFThis ethnographic study prioritises the emic perspectives of Syrian Muslim refugees resettled to North East Scotland by means of conversations about God. Beginning with a model borrowed from the monastic tradition that has an approach towards the other of "dilatato corde," an expanded heart, it explores the implications of employing a model of inter-religious dialogue that inverts existing power dynamics and brings to therefore a peripheral voice. The purpose of this study is to challenge paradigms of exclusion, by learning directly from those who have been uprooted by war and resettled as refugees in Scotland, and to understand theological perspectives of those at the margins. The narrative approach in Part II of the thesis interweaves the voices of refugees with fieldwork observations and existing literature that verifies the themes. Echoing the theological meta-narrative that emerged in conversation with the informants, Chapter Three considers the experience of resettlement through the prism of “estrangement” (al-ghurba), Chapter Four focuses on the concept of “homeland” (al-waṭan) from a position of exile, and Chapter Five seeks an understanding of “God” (allāh) as seen through the eyes of the refugee. The study provides a written record of the life narratives, at a particular moment in time, of a people whose voices are not readily heard, offers insights into the inner world of a small number of Muslim refugees, and illustrates the extent to which Islam, and religion more generally, has an influence in, and implications for, the field of refugee resettlement
Genetic coupling of mate recognition systems in the genomic era
Get PDFFunding: MGR is funded by the NERC, UK (Grant NE/V001566/1). RKB is funded by The Leverhulme Trust and the Swedish Research Council.The concept of “genetic coupling” in mate recognition systems arose in the 1960s as a potential mechanism to maintain coordination between signals and receivers during evolutionary divergence. At its most basic it proposed that the same genes might influence trait and preference, and therefore mutations could result in coordinated changes in both traits. Since then, the concept has expanded in scope and is often used to include linkage or genetic correlation between recognition system components. Here we review evidence for genetic coupling, concentrating on proposed examples of a common genetic basis for signals and preferences. Mapping studies have identified several examples of tight genetic linkage between genomic regions influencing signals and preferences, or assortative mating. Whether this extends as far as demonstrating pleiotropy remains a more open question. Some studies, notably of Drosophila, have identified genes in the sex determination pathway and in pheromonal communication where single loci can influence both signals and preferences. This may be based on isoform divergence, in which sex- and tissue-specific effects are facilitated by alternative spicing, or on regulatory divergence. Hence it is not clear that such examples provide compelling evidence of pleiotropy in the sense that “magic mutations” could maintain trait coordination. Rather, coevolution may be facilitated by regulatory divergence but require different mutations or coevolution across isoforms. Reconsidering the logic of genetic coupling, it may be that pleiotropy could actually be less effective than linkage if distinct but associated variants allow molecular coevolution to occur more readily than potentially “unbalanced” mutations in single genes. Genetic manipulation or studies of mutation order effects during divergence are challenging but perhaps the only way to disentangle the role of pleiotropy versus close linkage in coordinated trait divergence.Peer reviewe
Development and validation of the C-SHADE Scale for measuring perpetration of common sexually harassing and aggressive behaviors in drinking environments
Get PDFFunding: This project was funded by a Canadian Institutes of Health Research (CIHR) Project Grant (PJT – 387960).Background Sexual aggression (SA) is ubiquitous in drinking environments, often seen as normal and acceptable; yet, targets of SA experience many negative consequences. This research aimed to develop a valid measure of common acts of SA in drinking settings for estimating prevalence and evaluating prevention initiatives. Methods We developed a questionnaire measure of common acts of sexual harassment and aggression in drinking environments (C-SHADE) based on descriptions of SA behavior from our own and others' research. The measure was validated in a cross-sectional survey of 335 men aged 19-25 using webpanels from an online survey company. Validation measures included: a modified version of the Sexual Experiences Survey (M-SES), measures of SA by peers in drinking environments, SA-related attitudes, expectancies about sexual effects of alcohol, and alcohol consumption. Results The C-SHADE showed high internal consistency (α = 0.96) and was significantly correlated with M-SES (r = 0.52), SA by peers (r = 0.61 to 0.70), SA-related attitudes/expectations (r = 0.38 to 0.55), and measures of alcohol consumption (r = 0.22 to 0.36). Overall, 71.9% participants reported SA using the C-SHADE versus 24.7% with the M-SES. We compared the responses of participants who reported perpetration on both measures (N = 83), only the C-SHADE (N = 141), and non-perpetrators (N = 89) (excluding 4 participants who reported perpetration only on the M-SES). The M-SES/C-SHADE perpetrators scored significantly higher than C-SHADE-only perpetrators and non-perpetrators on most SA-related and drinking measures, while C-SHADE-only perpetrators scored significantly higher than non-perpetrators on peer SA and two attitude measures. Conclusions The C-SHADE is suitable for measuring prevalence and evaluating interventions in drinking settings. The C-SHADE confirmed high prevalence of SA in drinking settings and identified an important group of C-SHADE-only perpetrators for whom interventions that focus on situational precipitators of SA in drinking settings may be especially useful.Peer reviewe
Collecting baleen whale blow samples by drone : a minimally intrusive tool for conservation genetics
Get PDF_Carol Newell, Donner Canadian Foundation, Elizabeth Haan, Fisheries and Oceans Canada_ Habitat Stewardship Program for Species at Risk, Save Our Seas Foundation, Willow Grove Foundation_In coastal British Columbia, Canada, marine megafauna such as humpback whales (Megaptera novaeangliae) and fin whales (Balaenoptera physalus velifera) have been subject to a history of exploitation and near extirpation. While their populations have been in recovery, significant threats are posed to these vulnerable species by proposed natural resource ventures in this region, in addition to the compounding effects of anthropogenic climate change. Genetic tools play a vital role in informing conservation efforts, but the associated collection of tissue biopsy samples can be challenging for the investigators and disruptive to the ongoing behaviour of the targeted whales. Here, we evaluate a minimally intrusive approach based on collecting exhaled breath condensate, or respiratory ‘blow’ samples, from baleen whales using an unoccupied aerial system (UAS), within Gitga'at First Nation territory for conservation genetics. Minimal behavioural responses to the sampling technique were observed, with no response detected 87% of the time (of 112 UAS deployments). DNA from whale blow (n = 88 samples) was extracted, and DNA profiles consisting of 10 nuclear microsatellite loci, sex identification and mitochondrial (mt) DNA haplotypes were constructed. An average of 7.5 microsatellite loci per individual were successfully genotyped. The success rates for mtDNA and sex assignment were 80% and 89% respectively. Thus, this minimally intrusive sampling method can be used to describe genetic diversity and generate genetic profiles for individual identification. The results of this research demonstrate the potential of UAS-collected whale blow for conservation genetics from a remote location.Peer reviewe
Selective aortic arch perfusion : a first-in-human observational cadaveric study
Get PDFBackground Selective aortic arch perfusion (SAAP) is a novel endovascular technique that combines thoracic aortic occlusion with extracorporeal perfusion of the brain and heart. SAAP may have a role in both haemorrhagic shock and in cardiac arrest due to coronary ischaemia. Despite promising animal studies, no data is available that describes SAAP in humans. The primary aim of this study was to assess the feasibility of selective aortic arch perfusion in humans. The secondary aim of the study was to assess the feasibility of achieving direct coronary artery access via the SAAP catheter as a potential conduit for salvage percutaneous coronary intervention. Methods Using perfused human cadavers, a prototype SAAP catheter was inserted into the descending aorta under fluoroscopic guidance via a standard femoral percutaneous access device. The catheter balloon was inflated and the aortic arch perfused with radio-opaque contrast. The coronary arteries were cannulated through the SAAP catheter. Results The procedure was conducted four times. During the first two trials the SAAP catheter was passed rapidly and without incident to the intended descending aortic landing zone and aortic arch perfusion was successfully delivered via the device. The SAAP catheter balloon failed on the third trial. On the fourth trial the left coronary system was cannulated using a 5Fr coronary guiding catheter through the central SAAP catheter lumen. Conclusions For the first time using a perfused cadaveric model we have demonstrated that a SAAP catheter can be easily and safely inserted and SAAP can be achieved using conventional endovascular techniques. The SAAP catheter allowed successful access to the proximal aorta and permitted retrograde perfusion of the coronary and cerebral circulation.Peer reviewe
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