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The information needs of contemporary academic researchers
This thesis looks at the information component of the research endeavour at a particularly interesting point in time, when strikingly new developments in both the scholarly world and its information environs cast doubt on the validity of anything and everything we have traditionally been holding true as to academic researchers' information needs and practices. Indeed, the host of societal demands driven transformations in the organisation, values and practices of scholarly knowledge production of recent years, coupled with the technology-enabled, rapidly evolving opportunities for creating, accessing and communicating information suggest that neither researchers' information needs, nor their attempts at meeting these needs could conceivably remain untouched. This state of affairs has been the impetus for undertaking the re-examination reported here of our long-established notions concerning scholarly information needs and practices. The study sets out, therefore, to investigate, analyse and systematically describe the information work of researchers in academe of the knowledge society. This, with the express aim of achieving a comprehensive, state-of-the-art portrayal of the generic, as well as the disciplinary and/or age specific information needs and corresponding information behaviour of today's university-based researchers. Towards this purpose, the thesis integrates three inter-related elements: a user-centred theoretical perspective, proposed by Nicholas (1996,2000), which views an information need as having eleven different dimensions; a state-of-the-art review, based on the literature; and a hybrid, field research project, conducted at the University of Haifa, Israel, comprising two consecutive stages, a two-phase qualitative stage of interviews, and a quantitative stage of a questionnaire survey. Thus, the theoretical perspective and the insights offered by the published literature in the field combine with the data collected for the present undertaking to inform the research questions. Unravelling the complex picture of contemporary academic researchers' information needs has proven to be an undertaking of exceptionally wide scope. Not only does it look at an entire information community, but also, utilising as it does the eleven-pronged analytical framework for assessing information needs, developed by Nicholas (1996,2000) on the basis of his conceptual approach, it also took a far more comprehensive view of the concept of research-related information need than other field-based investigations. Endeavouring to draw an overarching portrayal of the information needs characterising today's academic researchers, the thesis opens, therefore, with the rationale for the investigation, its aims, scope and setting. Then it proceeds to recap our traditionally held notions concerning scholarly work and its information component by reviewing the literature depicting the socio-cultural context of the scientific enterprise. Next the theoretical foundations of the investigation are delineated, followed by a detailed account of the field-work based insights gleaned into the information component of academic research work. Then all of the information presented is interpreted in the light of the research questions, for a comprehensive portrayal of contemporary researchers' information needs and practices to materialise. As surmised, many elements of the present-day, research-associated in formation work, as they emerge from the findings of this investigation, comprise changed or changing features. Nevertheless, the overall picture bears testimony to the continued existence and relevance of those core scholarly information needs, which are dictated by the basic professional values of academics and their discipline-specific research work conventions. Thus, today's researchers may define their information needs in terms of the changing realities of conducting research in academe of the knowledge society, may more or less happily embrace information work practices,w hich involve novel responses to the new challenges posed to them, but their fundamental information needs seem to have remained by and large unaffected by the recent upheavals in the scholarly world and its information environs. Indeed, the present study re-affirms yet again that the inter-disciplinary differences in analytic processes and research work-habits, stemming as they do from the very nature of the way knowledge grows in each of the knowledge domains, entail discretionary information needs and uses both on the inter-individual and the intra-individual level. These needs, summarised here as a generalised profile of scientists, socials scientists, and humanists, whilst clearly indicative of changing elements in contemporary research-associated in formation work, nevertheless bear testimony to the ongoing vital importance of heeding the research-work conventions rooted specific information needs of the different communities comprising the academic population
N=8 superconformal gauge theories and M2 branes
Based on recent developments, in this letter we find 2+1 dimensional gauge
theories with scale invariance and N=8 supersymmetry. The gauge theories are
defined by a Lagrangian and are based on an infinite set of 3-algebras,
constructed as an extension of ordinary Lie algebras. Recent no-go theorems on
the existence of 3-algebras are circumvented by relaxing the assumption that
the invariant metric is positive definite. The gauge group is non compact, and
its maximally compact subgroup can be chosen to be any ordinary Lie group,
under which the matter fields are adjoints or singlets. The theories are parity
invariant and do not admit any tunable coupling constant. In the case of SU(N)
the moduli space of vacua contains a branch of the form (R^8)^N/S_N. These
properties are expected for the field theory living on a stack of M2 branes.Comment: 14 pages, no figure
Strings from Tachyons
We propose a new interpretation of the c=1 matrix model as the world-line
theory of N unstable D-particles, in which the hermitian matrix is provided by
the non- abelian open string tachyon. For D-particles in 1+1-d string theory,
we find a direct quantitative match between the closed string emission due to a
rolling tachyon and that due to a rolling eigenvalue in the matrix model. We
explain the origin of the double-scaling limit, and interpret it as an extreme
representative of a large equivalence class of dual theories. Finally, we
define a concrete decoupling limit of unstable D-particles in IIB string theory
that reduces to the c=1 matrix model, suggesting that 1+1-d string theory
represents the near-horizon limit of an ultra-dense gas of IIB D-particles.Comment: 30 pages, 4 figures; v2: added references, improved discussion of
Liouville boundary states, v3: small correction
Two-dimensional superstrings and the supersymmetric matrix model
We present evidence that the supersymmetric matrix model of Marinari and
Parisi represents the world-line theory of N unstable D-particles in type II
superstring theory in two dimensions. This identification suggests that the
matrix model gives a holographic description of superstrings in a
two-dimensional black hole geometry.Comment: 22 pages, 2 figures; v2: corrected eqn 4.6; v3: corrected appendices
and discussion of vacua, added ref
Cyprus as an ancient hub for house mice and humans
© 2018 The Authors. Journal of Biogeography Published by John Wiley & Sons Ltd Aim: The distribution of the western house mouse (Mus musculus domesticus) around the world has been strongly influenced by the movement of humans. The close association between the house mouse and human phylogeography has been primarily studied in the peripheral distribution of the species. Here, we inferred the complex colonization history of Cyprus, situated close to the centre of the house mouse distribution and one of the first European islands to be colonized by the species. We investigated the resulting complexity of house mouse population genetics as well as considering the value of the house mouse as a bioproxy for studying modern human movement. Location: The study was carried out on Cyprus. Methods: The analysis was performed using 221 new mitochondrial D-loop sequences and assessed the fine-scale population genetic structure using 18 autosomal microsatellite loci from 191 modern house mice specimens. Results: We found a high genetic variability in the island that is illustrated by the presence of individuals from 9 of the 11 previously identified house mouse haplogroups for the D-loop, reflecting the hub-like nature of the island to mice. Two main waves of mouse introductions were tentatively identified based on coalescent and mismatch analysis. The first is apparently related to the Bronze Age expansion and the second one to more recent human movements. Cyprus represents an island with high complexity due to different introductions related to human transport and activity. Main conclusions: The dispersal of mice along with humans has left a complex footprint on the island with two main waves of introductions suggested. The phylogeography of the house mouse on Cyprus is in concordance with the complex human colonization history of the island and validates the use of the house mouse as a proxy to study human migration
Interoperable and scalable data analysis with microservices: applications in metabolomics.
Developing a robust and performant data analysis workflow that integrates all necessary components whilst still being able to scale over multiple compute nodes is a challenging task. We introduce a generic method based on the microservice architecture, where software tools are encapsulated as Docker containers that can be connected into scientific workflows and executed using the Kubernetes container orchestrator.
We developed a Virtual Research Environment (VRE) which facilitates rapid integration of new tools and developing scalable and interoperable workflows for performing metabolomics data analysis. The environment can be launched on-demand on cloud resources and desktop computers. IT-expertise requirements on the user side are kept to a minimum, and workflows can be re-used effortlessly by any novice user. We validate our method in the field of metabolomics on two mass spectrometry, one nuclear magnetic resonance spectroscopy and one fluxomics study. We showed that the method scales dynamically with increasing availability of computational resources. We demonstrated that the method facilitates interoperability using integration of the major software suites resulting in a turn-key workflow encompassing all steps for mass-spectrometry-based metabolomics including preprocessing, statistics and identification. Microservices is a generic methodology that can serve any scientific discipline and opens up for new types of large-scale integrative science.
The PhenoMeNal consortium maintains a web portal (https://portal.phenomenal-h2020.eu) providing a GUI for launching the Virtual Research Environment. The GitHub repository https://github.com/phnmnl/ hosts the source code of all projects.
Supplementary data are available at Bioinformatics online
Regulation of 5-HT Receptors and the Hypothalamic-Pituitary-Adrenal Axis
Disturbances in the serotonin (5-HT) system is the neurobiological abnormality most consistently associated with suicide. Hyperactivity of the hypothalmic-pituitary-adrenal (HPA) axis is also described in suicide victims. The HPA axis is the classical neuroendocrine system that responds to stress and whose final product, corticosteroids, targets components of the limbic system, particularly the hippocampus. We will review resulsts from animal studies that point to the possibility that many of the 5-HT receptor changes observed in suicide brains may be a result of, or may be worsened by, the HPA overactivity that may be present in some suicide victims. The results of these studies can be summarized as follows: (1) chronic unpredictable stress produces high corticosteroid levels in rats; (2) chronic stress also results in changes in specific 5-HT receptors (increases in cortical 5-HT2A and decreases in hipocampal 5-HT1A and 5-HT1B); (3) chronic antidepressant administration prevents many of the 5-HT receptor changes observed after stress; and (4) chronic antidepressant administration reverses the overactivity of the HPA axis. If indeed 5-HT receptors have a partial role in controlling affective states, then their modulation by corticosteroids provides a potential mechanism by which these hormones may regulate mood. These data may also provide a biological understanding of how stressful events may increase the risk for suicide in vulnerable individuals and may help us elucidate the neurobiological underpinnings of treatment resistance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73437/1/j.1749-6632.1997.tb52357.x.pd
Drug-gene interactions of antihypertensive medications and risk of incident cardiovascular disease: A pharmacogenomics study from the CHARGE consortium
Background Hypertension is a major risk factor for a spectrum of cardiovascular diseases (CVD), including myocardial infarction, sudden death, and stroke. In the US, over 65 million people have high blood pressure and a large proportion of these individuals are prescribed antihypertensive medications. Although large long-term clinical trials conducted in the last several decades have identified a number of effective antihypertensive treatments that reduce the risk of future clinical complications, responses to therapy and protection from cardiovascular events vary among individuals. Methods Using a genome-wide association study among 21,267 participants with pharmaceutically treated hypertension, we explored the hypothesis that genetic variants might influence or modify the effectiveness of common antihypertensive therapies on the risk ofmajor cardiovascular outcomes. The classes of drug treatments included angiotensin-converting enzyme inhibitors, beta-blockers, calcium channel blockers, and diuretics. In the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, each study performed array-based genome-wide genotyping, imputed to HapMap Phase II reference panels, and used additive genetic models in proportional hazards or logistic regressionmodels to evaluate drug-gene interactions for each of four therapeutic drug classes. We used meta-analysis to combine study-specific interaction estimates for approximately 2 million single nucleotide polymorphisms (SNPs) in a discovery analysis among 15,375 European Ancestry participants (3,527 CVD cases) with targeted follow-up in a case-only study of 1,751 European Ancestry GenHAT participants as well as among 4,141 African-Americans (1,267 CVD cases). Results Although drug-SNP interactions were biologically plausible, exposures and outcomes were well measured, and power was sufficient to detect modest interactions, we did not identify any statistically significant interactions from the four antihypertensive therapy meta-analyses (Pinteraction > 5.0×10-8). Similarly, findings were null for meta-analyses restricted to 66 SNPs with significant main effects on coronary artery disease or blood pressure from large published genom
Risk factors for infections caused by carbapenem-resistant Enterobacterales: an international matched case-control-control study (EURECA)
Cases were patients with complicated urinary tract infection (cUTI), complicated intraabdominal (cIAI), pneumonia or bacteraemia from other sources (BSI-OS) due to CRE; control groups were patients with infection caused by carbapenem-susceptible Enterobacterales (CSE), and by non-infected patients, respectively. Matching criteria included type of infection for CSE group, ward and duration of hospital admission. Conditional logistic regression was used to identify risk factors. Findings Overall, 235 CRE case patients, 235 CSE controls and 705 non-infected controls were included. The CRE infections were cUTI (133, 56.7%), pneumonia (44, 18.7%), cIAI and BSI-OS (29, 12.3% each). Carbapenemase genes were found in 228 isolates: OXA-48/like, 112 (47.6%), KPC, 84 (35.7%), and metallo-beta-lactamases, 44 (18.7%); 13 produced two. The risk factors for CRE infection in both type of controls were (adjusted OR for CSE controls; 95% CI; p value) previous colonisation/infection by CRE (6.94; 2.74-15.53; <0.001), urinary catheter (1.78; 1.03-3.07; 0.038) and exposure to broad spectrum antibiotics, as categorical (2.20; 1.25-3.88; 0.006) and time-dependent (1.04 per day; 1.00-1.07; 0.014); chronic renal failure (2.81; 1.40-5.64; 0.004) and admission from home (0.44; 0.23-0.85; 0.014) were significant only for CSE controls. Subgroup analyses provided similar results. Interpretation The main risk factors for CRE infections in hospitals with high incidence included previous coloni-zation, urinary catheter and exposure to broad spectrum antibiotics
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