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EQRbot: A chatbot delivering EQR argument-based explanations
Data availability statement: The provided link: https://github.com/FCast07/EQRbot refers to the GitHub repository that stores the chatbot programming code.Recent years have witnessed the rise of several new argumentation-based support systems, especially in the healthcare industry. In the medical sector, it is imperative that the exchange of information occurs in a clear and accurate way, and this has to be reflected in any employed virtual systems. Argument Schemes and their critical questions represent well-suited formal tools for modeling such information and exchanges since they provide detailed templates for explanations to be delivered. This paper details the EQR argument scheme and deploys it to generate explanations for patients' treatment advice using a chatbot (EQRbot). The EQR scheme (devised as a pattern of Explanation-Question-Response interactions between agents) comprises multiple premises that can be interrogated to disclose additional data. The resulting explanations, obtained as instances of the employed argumentation reasoning engine and the EQR template, will then feed the conversational agent that will exhaustively convey the requested information and answers to follow-on users' queries as personalized Telegram messages. Comparisons with a previous baseline and existing argumentation-based chatbots illustrate the improvements yielded by EQRbot against similar conversational agents.This research was partially funded by the UK Engineering & Physical Sciences Research Council (EPSRC) under Grant #EP/P010105/1
Heritable functional architecture in human visual cortex
How much of the functional organization of our visual system is inherited? Here we tested the heritability of retinotopic maps in human visual cortex using functional magnetic resonance imaging. We demonstrate that retinotopic organization shows a closer correspondence in monozygotic (MZ) compared to dizygotic (DZ) twin pairs, suggesting a partial genetic determination. Using population receptive field (pRF) analysis to examine the preferred spatial location and selectivity of these neuronal populations, we estimate a heritability around 10–20% for polar angle preferences and spatial selectivity, as quantified by pRF size, in extrastriate areas V2 and V3. Our findings are consistent with heritability in both the macroscopic arrangement of visual regions and stimulus tuning properties of visual cortex. This could constitute a neural substrate for variations in a range of perceptual effects, which themselves have been found to be at least partially genetically determined. These findings also add convergent evidence for the hypothesis that functional map topology is linked with cortical morphology
Correlation function of null polygonal Wilson loops with local operators
We consider the correlator of a light-like polygonal Wilson loop
with n cusps with a local operator (like the dilaton or the chiral primary
scalar) in planar N =4 super Yang-Mills theory. As a consequence of conformal
symmetry, the main part of such correlator is a function F of 3n-11 conformal
ratios. The first non-trivial case is n=4 when F depends on just one conformal
ratio \zeta. This makes the corresponding correlator one of the simplest
non-trivial observables that one would like to compute for generic values of
the `t Hooft coupling \lambda. We compute F(\zeta,\lambda) at leading order in
both the strong coupling regime (using semiclassical AdS5 x S5 string theory)
and the weak coupling regime (using perturbative gauge theory). Some results
are also obtained for polygonal Wilson loops with more than four edges.
Furthermore, we also discuss a connection to the relation between a correlator
of local operators at null-separated positions and cusped Wilson loop suggested
in arXiv:1007.3243.Comment: 36 pages, 2 figure
Comparison of Reliability of Rapid Diagonostic Test to Microscopy in the Diagnosis of Malaria at Gulu Regional Referral Hospital
Background: Malaria is one of the leading causes of mortality in sub-Saharan Africa and continues to be a threat to life. Everyday 320 people die due to malaria in Uganda. Statistics from the ministry of health show that of all outpatient visits at health Centres, malaria represents 25 - 40 % with 9 - 14 % in in-patient. Microscopy remains the main stay for malaria diagnosis. Nevertheless it is slow and needs a lot of experience and expertise, consequently there is need to use a faster method but retaining the precision of the microscope.Objective: To determine the reliability of the rapid diagnostic test in comparison to microscopy in the diagnosis of malaria thereafter improve the management of malaria.Design: An experimental study.Setting: Gulu Regional Referral Hospital laboratories.Subjects: The study was experimental; using 250 malarial suspected participants with fever .The malaria rapid diagnostic method and microscopy of the stained malarial slides were the methods used.Results: Of the 250 samples, 214 were found to be negative using microscopy and 208 using Rapid Diagnostic Test suggesting over suspicion of malaria. Microscopy had a sensitivity of 85.7%, specificity of 94.7% and Negative predictive value (NPV) of 97.2%.Conclusion: RDTs can be used to quickly confirm the clinical diagnosis of malaria to reduce irrational use of anti-malarials when microscopy is not available before initiating treatment to avoid irrational use of drugs. However due to the cost, microscopy still remains the gold standard method for the diagnosis of Malaria
Uncovering the overlapping community structure of complex networks in nature and society
Many complex systems in nature and society can be described in terms of
networks capturing the intricate web of connections among the units they are
made of. A key question is how to interpret the global organization of such
networks as the coexistence of their structural subunits (communities)
associated with more highly interconnected parts. Identifying these a priori
unknown building blocks (such as functionally related proteins, industrial
sectors and groups of people) is crucial to the understanding of the structural
and functional properties of networks. The existing deterministic methods used
for large networks find separated communities, whereas most of the actual
networks are made of highly overlapping cohesive groups of nodes. Here we
introduce an approach to analysing the main statistical features of the
interwoven sets of overlapping communities that makes a step towards uncovering
the modular structure of complex systems. After defining a set of new
characteristic quantities for the statistics of communities, we apply an
efficient technique for exploring overlapping communities on a large scale. We
find that overlaps are significant, and the distributions we introduce reveal
universal features of networks. Our studies of collaboration, word-association
and protein interaction graphs show that the web of communities has non-trivial
correlations and specific scaling properties.Comment: The free academic research software, CFinder, used for the
publication is available at the website of the publication:
http://angel.elte.hu/clusterin
Graphene for spintronics: giant Rashba splitting due to hybridization with Au
Graphene in spintronics has so far primarily meant spin current leads of high
performance because the intrinsic spin-orbit coupling of its pi-electrons is
very weak. If a large spin-orbit coupling could be created by a proximity
effect, the material could also form active elements of a spintronic device
such as the Das-Datta spin field-effect transistor, however, metal interfaces
often compromise the band dispersion of massless Dirac fermions. Our
measurements show that Au intercalation at the graphene-Ni interface creates a
giant spin-orbit splitting (~100 meV) in the graphene Dirac cone up to the
Fermi energy. Photoelectron spectroscopy reveals hybridization with Au-5d
states as the source for the giant spin-orbit splitting. An ab initio model of
the system shows a Rashba-split dispersion with the analytically predicted
gapless band topology around the Dirac point of graphene and indicates that a
sharp graphene-Au interface at equilibrium distance will account for only ~10
meV spin-orbit splitting. The ab initio calculations suggest an enhancement due
to Au atoms that get closer to the graphene and do not violate the sublattice
symmetry.Comment: 16 pages (3 figures) + supplementary information 16 pages (14
figures
Renormalization Group Approach to Cosmological Back Reaction Problems
We investigated the back reaction of cosmological perturbations on the
evolution of the universe using the second order perturbation of the Einstein's
equation. To incorporate the back reaction effect due to the inhomogeneity into
the framework of the cosmological perturbation, we used the renormalization
group method. The second order zero mode solution which appears by the
non-linearities of the Einstein's equation is regarded as a secular term of the
perturbative expansion, we renormalized a constant of integration contained in
the background solution and absorbed the secular term to this constant. For a
dust dominated universe, using the second order gauge invariant quantity, we
derived the renormalization group equation which determines the effective
dynamics of the Friedman-Robertson-Walker universe with the back reaction
effect in a gauge invariant manner. We obtained the solution of the
renormalization group equation and found that perturbations of the scalar mode
and the long wavelength tensor mode works as positive spatial curvature, and
the short wavelength tensor mode as radiation fluid.Comment: 18 pages, revtex, to appear in Phys. Rev.
Correlation functions of three heavy operators - the AdS contribution
We consider operators in N=4 SYM theory which are dual, at strong coupling,
to classical strings rotating in S^5. Three point correlation functions of such
operators factorize into a universal contribution coming from the AdS part of
the string sigma model and a state-dependent S^5 contribution. Consequently a
similar factorization arises for the OPE coefficients. In this paper we
evaluate the AdS universal factor of the OPE coefficients which is explicitly
expressed just in terms of the anomalous dimensions of the three operators.Comment: 49 pages, 3 figures; v.2 references corrected; v3: corrected
discussion in section 5, results unchange
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