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Mirror symmetry for higher genus curves is usually formulated and studied in terms of Landau–Ginzburg models; however the critical locus of the superpotential is arguably of greater intrinsic relevance to mirror symmetry than the whole Landau–Ginzburg model. Accordingly, we propose a new approach to the A-model of the mirror, viewed as a trivalent configuration of rational curves together with some extra data at the nodal points. In this context, we introduce a version of Lagrangian Floer theory and the Fukaya category for trivalent graphs, and show that homological mirror symmetry holds, namely, that the Fukaya category of a trivalent configuration of rational curves is equivalent to the derived category of a non-Archimedean generalized Tate curve. To illustrate the concrete nature of this equivalence, we show how explicit formulas for theta functions and for the canonical map of the curve arise naturally under mirror symmetry. [ABSTRACT FROM AUTHOR]

In every matured theory, there is a need to investigate possible relationships between considered objects. To address this issue, it is natural to relate a category with given model of computing. Thanks to such approach, many properties are unified and simplified. In this paper, we investigate how category theory can be used to give a faithful semantics for reaction systems. In particular, we propose and discuss possible approaches to the problem of defining morphisms between reaction systems. We provide the definition of morphism that keeps the behaviour of the original reaction system. Especially, some equivalences of reaction systems are reflected in terms of morphisms. For this purpose we expressed isomorphisms and sections in term of transition systems. Moreover, the accelerating morphism defined in the last section gives a new approach for including time in reaction systems. [ABSTRACT FROM AUTHOR]

Gauging is a powerful operation on symmetries in quantum field theory (QFT), as it connects distinct theories and also reveals hidden structures in a given theory. We initiate a systematic investigation of gauging discrete generalized symmetries in two-dimensional QFT. Such symmetries are described by topological defect lines (TDLs) which obey fusion rules that are non-invertible in general. Despite this seemingly exotic feature, all well-known properties in gauging invertible symmetries carry over to this general setting, which greatly enhances both the scope and the power of gauging. This is established by formulating generalized gauging in terms of topological interfaces between QFTs, which explains the physical picture for the mathematical concept of algebra objects and associated module categories over fusion categories that encapsulate the algebraic properties of generalized symmetries and their gaugings. This perspective also provides simple physical derivations of well-known mathematical theorems in category theory from basic axiomatic properties of QFT in the presence of such interfaces. We discuss a bootstrap-type analysis to classify such topological interfaces and thus the possible generalized gaugings and demonstrate the procedure in concrete examples of fusion categories. Moreover we present a number of examples to illustrate generalized gauging and its properties in concrete conformal field theories (CFTs). In particular, we identify the generalized orbifold groupoid that captures the structure of fusion between topological interfaces (equivalently sequential gaugings) as well as a plethora of new self-dualities in CFTs under generalized gaugings. [ABSTRACT FROM AUTHOR]

A new marker reflecting the pathophysiology of chronic kidney disease (CKD) has been desired for its therapy. In this study, we developed a virtual space where data in medical words and those of actual CKD patients were unified by natural language processing and category theory. A virtual space of medical words was constructed from the CKD-related literature (n = 165,271) using Word2Vec, in which 106,612 words composed a network. The network satisfied vector calculations, and retained the meanings of medical words. The data of CKD patients of a cohort study for 3 years (n = 26,433) were transformed into the network as medical-word vectors. We let the relationship between vectors of patient data and the outcome (dialysis or death) be a marker (inner product). Then, the inner product accurately predicted the outcomes: C-statistics of 0.911 (95% CI 0.897, 0.924). Cox proportional hazards models showed that the risk of the outcomes in the high-inner-product group was 21.92 (95% CI 14.77, 32.51) times higher than that in the low-inner-product group. This study showed that CKD patients can be treated as a network of medical words that reflect the pathophysiological condition of CKD and the risks of CKD progression and mortality. [ABSTRACT FROM AUTHOR]

We developed a model to represent the time evolution phenomena of life through physics constraints. To do this, we took into account that living organisms are open systems that exchange messages through intracellular communication, intercellular communication and sensory systems, and introduced the concept of a message force field. As a result, we showed that the maximum entropy generation principle is valid in time evolution. Then, in order to explain life phenomena based on this principle, we modelled the living system as a nonlinear oscillator coupled by a message and derived the governing equations. The governing equations consist of two laws: one states that the systems are synchronized when the variation of the natural frequencies between them is small or the coupling strength through the message is sufficiently large, and the other states that the synchronization is broken by the proliferation of biological systems. Next, to simulate the phenomena using data obtained from observations of the temporal evolution of life, we developed an inference model that combines physics constraints and a discrete surrogate model using category theory, and simulated the phenomenon of early embryogenesis using this inference model. The results show that symmetry creation and breaking based on message force fields can be widely used to model life phenomena. [ABSTRACT FROM AUTHOR]

Some cognitive linguists (Rosch et al. Cognit Psychol 8:382–439, 1976; Ungerer and Schmid An introduction to cognitive linguistics, Pearson Education Limited, London, England, 2006) believe the basic level category has cognitive economy because the basic level category allows obtaining the maximum amount of information about an item with the lowest cognitive effort. Whether it is also true for L2 learners has not been verified so far. This study examined whether Chinese English learners' cognitive load of basic level category is lower than that of superordinate category and subordinate category. The eye movement data, including that of total duration of fixations, total number of fixations, duration of first fixation, and average duration of fixations, generated by 31 Chinese English learners while reading sentences with different levels of category words, were collected and analyzed. The results showed that Chinese English learners' cognitive load of the basic level category was the lowest. This study provides cross-linguistic experimental evidence for the basic level category theory, and also shows the cognitive economy of basic level categories is an intrinsic psychological property, no matter whether it is the first language or the second language that the readers use. [ABSTRACT FROM AUTHOR]

In this paper, we formalize precisely the sense in which the application of a cellular automaton to partial configurations is a natural extension of its local transition function through the categorical notion of Kan extension. In fact, the two possible ways to do such an extension and the ingredients involved in their definition are related through Kan extensions in many ways. These relations provide additional links between computer science and category theory, and also give a new point of view on the famous Curtis–Hedlund theorem of cellular automata from the extended topological point of view provided by category theory. These links also allow to relatively easily generalize concepts pioneered by cellular automata to arbitrary kinds of possibly evolving spaces. No prior knowledge of category theory is assumed for the most part. [ABSTRACT FROM AUTHOR]

In category learning, transfer emerges when individuals apply the knowledge or strategy learned with one set of stimuli to a novel set. Under multisensory circumstances, it remains unclear whether the transfer occurs differently in implicit and explicit category learning, as it remains controversial whether explicit knowledge is indispensable for transfer. To address this issue, we adopted multisensory stimuli in implicit (i.e., information integration, II) and explicit (i.e., conjunctive rule-based, RB) category learning tasks. Experiment 1 showed that when training and novel sets shared the same feature modalities, spontaneous transfer without feedback was perfect in the II condition but impaired in the RB condition. However, with feedback, the dependent transfer occurred equally between conditions. Experiment 2 revealed that when across different feature modalities, no spontaneous transfer was observed in any of the two conditions. A dependent transfer occurred in the RB but not in the II condition. Experiment 3 found that delayed feedback disrupted II task performance but not RB task performance, indicating that people did not learn the II task using an explicit rule. The current study demonstrated that transfer to novel stimuli could emerge in explicit and implicit category learning within feature modalities. However, the transfer across feature modalities could only arise with feedback in explicit learning. We further discuss these findings' meaning with the current category learning theory. [ABSTRACT FROM AUTHOR]

We study the continuity of pullback random attractors A λ , where the parameter belongs to a complete metric space Λ . By a Hausdorff sub-norm space, we mean the collection of all nonempty compact subsets of the state space, equipped by the Hausdorff metric as well as a sub-norm. Under weaker conditions, we prove that the binary map (λ , s) → A λ (s , θ s ω) is continuous at all points of Λ ∗ × R with respect to the Hausdorff metric, where Λ ∗ is residual and dense in Λ , and that the binary map is continuous under the sub-norm if and only if each fibre of attractors is a point. The proofs of these results are based on the discussion of continuous operators on the Hausdorff sub-norm space as well as the theory of Baire category. For the g-Navier–Stokes equation driven by random density, stochastic noise and time-dependent forces, we establish the residual continuity and full upper semi-continuity of pullback random attractors on the Fréchet space formed from all backward tempered forces. [ABSTRACT FROM AUTHOR]

In this paper, we complete the study started in Ambrosio and Rădulescu (J Math Pures Appl (9) 142:101–145, 2020) on the concentration phenomena for a class of fractional (p, q)-Schrödinger equations involving the fractional critical Sobolev exponent. More precisely, we focus our attention on the following class of fractional (p, q)-Laplacian problems: (- Δ) p s u + (- Δ) q s u + V (ε x) (u p - 1 + u q - 1) = f (u) + u q s ∗ - 1 in R N , u ∈ W s , p (R N) ∩ W s , q (R N) , u > 0 in R N , where ε > 0 is a small parameter, s ∈ (0 , 1) , 1 < p < q < N s , q s ∗ = Nq N - s q is the fractional critical Sobolev exponent, (- Δ) r s , with r ∈ { p , q } , is the fractional r-Laplacian operator, V : R N → R is a positive continuous potential such that inf ∂ Λ V > inf Λ V for some bounded open set Λ ⊂ R N , and f : R → R is a continuous nonlinearity with subcritical growth. With the aid of minimax theorems and the Ljusternik–Schnirelmann category theory, we obtain multiple solutions by employing the topological construction of the set where the potential V attains its minimum. We also establish a multiplicity result when f (t) = t γ - 1 + μ t τ - 1 , with 1 < p < q < γ < q s ∗ < τ and μ > 0 sufficiently small, by combining a truncation argument with a Moser-type iteration. [ABSTRACT FROM AUTHOR]

We are interested in properties, especially injectivity (in the sense of category theory), of the ternary rings of operators generated by certain subsets of an inverse semigroup via the regular representation. We determine all subsets of the extended bicyclic semigroup which are closed under the triple product x y ∗ z (called semiheaps) and show that the weakly closed ternary rings of operators generated by them are injective operator spaces. [ABSTRACT FROM AUTHOR]

The monograph "Strong Artificial Intelligence. On the Approaches to Superintelligence," referenced by this paper, provides a cross-disciplinary review of Artificial General Intelligence (AGI). As an anthropomorphic direction of research, it considers Brain Principles Programming (BPP)—the formalization of universal mechanisms (principles) of the brain's work with information, which are implemented at all levels of the organization of nervous tissue. This monograph provides a formalization of these principles in terms of the category theory. However, this formalization is not enough to develop algorithms for working with information. In this paper, for the description and modeling of BPP, it is proposed to apply mathematical models and algorithms developed by us earlier that modeling cognitive functions, which are based on well-known physiological, psychological and other natural science theories. The paper uses mathematical models and algorithms of the following theories: P.K. Anokhin's Theory of Functional Brain Systems, Eleonor Rosch's prototypical categorization theory, Bob Rehder's theory of causal models and "natural" classification. As a result, the formalization of the BPP is obtained and computer examples are given that demonstrate the algorithms operation. [ABSTRACT FROM AUTHOR]

This document is a preface to a special issue of the journal Natural Computing, focusing on reaction systems. Reaction systems are a model of computation inspired by the interactions between biochemical reactions in living cells. The preface provides an overview of the concept of reaction systems and their applications in various research areas. It also introduces the articles included in the special issue, which cover topics such as extensions to the reaction systems model, solving NP-complete problems, debugging techniques, and connections to other computational models. The preface concludes with acknowledgements to the contributors, referees, and sponsors of the workshop series on reaction systems. [Extracted from the article]

In category theory circles it is well-known that the Schreier theory of group extensions can be understood in terms of the Grothendieck construction on indexed categories. However, it is seldom discussed how this relates to extensions of monoids. We provide an introduction to the generalised Grothendieck construction and apply it to recover classifications of certain classes of monoid extensions (including Schreier and weakly Schreier extensions in particular). [ABSTRACT FROM AUTHOR]

The goal of this paper is to establish an equivalence of profinite completions of pro-spaces in model category theory and in ∞ -category theory. As an application, we show that the author's comparison theorem for algebro-geometric objects in the setting of model categories recovers that of David Carchedi in the setting of ∞ -categories. [ABSTRACT FROM AUTHOR]

The paper has two parts, in the first part, we apply the localisation technique to the Rozansky–Witten theory on compact hyperkähler targets. We do so via first reformulating the theory as some supersymmetric sigma-model. We obtain the exact formula for the partition function with Wilson loops on S 1 × Σ g and the lens spaces, the results match with earlier computations using Feynman diagrams on K3. The second part is motivated by a very curious paper (Gukov in J Geom Phys 168, 104311, 2021), where the equivariant index formula for the dimension of the Hilbert space of the Rozansky–Witten theory is interpreted as a kind of Verlinde formula. In this interpretation, the fixed points of the target hyperkähler geometry correspond to certain 'states'. We extend the formalism of part one to incorporate equivariance on the target geometry. For certain non-compact hyperkähler geometry, we can apply the tilting theory to the derived category of coherent sheaves, whose objects label the Wilson loops, allowing us to pick a basis for the latter. We can then compute the fusion products in this basis and we show that the objects that have diagonal fusion rules are intimately related to the fixed points of the geometry. Using these objects as basis to compute the dimension of the Hilbert space leads back to the Verlinde formula, thus answering the question that motivated the paper. [ABSTRACT FROM AUTHOR]

Using the design method proposed by Kunii, this study mathematically explains the achievement of Kublai of merging two different societies to build a globalized nation after conquering China. The considered design method, called incrementally modular abstraction hierarchy, consists of seven levels, from the most abstract, homotopy, to the most concrete, computer graphics. Moreover, it allows a flexible design while moving up and down its hierarchy. Using this method, we attempt to restore the concepts of Kublai, aiming to build a globalized state by combining nomadic and agricultural cultures. Specifically, we examine the use of two capitals to resolve the problem of different lifestyles of the Mongolian Khan, who moved between the summer and winter camps of the nomads, and the Chinese Emperor, who lived in a fixed palace of the agricultural people. By incorporating the category theory into Kunii's method, we discuss the adjunction of the Mongolian 1000-household social and military system based on decimal numbers with the Chinese bureaucratic system. The inclusion of the category theory in his original method allows visualization by programming, making the design more versatile and flexible. [ABSTRACT FROM AUTHOR]

We prove that four different ways of defining Cartesian fibrations and the Cartesian model structure are all Quillen equivalent: On marked simplicial sets (due to Lurie [31]), On bisimplicial spaces (due to deBrito [12]), On bisimplicial sets, On marked simplicial spaces. The main way to prove these equivalences is by using the Quillen equivalences between quasi-categories and complete Segal spaces as defined by Joyal–Tierney and the straightening construction due to Lurie. [ABSTRACT FROM AUTHOR]

On a widespread naturalist view, the meanings of mathematical terms are determined, and can only be determined, by the way we use mathematical language—in particular, by the basic mathematical principles we're disposed to accept. But it's mysterious how this can be so, since, as is well known, minimally strong first-order theories are non-categorical and so are compatible with countless non-isomorphic interpretations. As for second-order theories: though they typically enjoy categoricity results—for instance, Dedekind's categoricity theorem for second-order PA and Zermelo's quasi-categoricity theorem for second-order ZFC—these results require full second-order logic. So appealing to these results seems only to push the problem back, since the principles of second-order logic are themselves non-categorical: those principles are compatible with restricted interpretations of the second-order quantifiers on which Dedekind's and Zermelo's results are no longer available. In this paper, we provide a naturalist-friendly, non-revisionary solution to an analogous but seemingly more basic problem—Carnap's Categoricity Problem for propositional and first-order logic—and show that our solution generalizes, giving us full second-order logic and thereby securing the categoricity or quasi-categoricity of second-order mathematical theories. Briefly, the first-order quantifiers have their intended interpretation, we claim, because we're disposed to follow the quantifier rules in an open-ended way. As we show, given this open-endedness, the interpretation of the quantifiers must be permutation-invariant and so, by a theorem recently proved by Bonnay and Westerståhl, must be the standard interpretation. Analogously for the second-order case: we prove, by generalizing Bonnay and Westerståhl's theorem, that the permutation invariance of the interpretation of the second-order quantifiers, guaranteed once again by the open-endedness of our inferential dispositions, suffices to yield full second-order logic. [ABSTRACT FROM AUTHOR]

Great efforts are now underway to control the coronavirus 2019 disease (COVID-19). Millions of people are medically examined, and their data keep piling up awaiting classification. The data are typically both incomplete and heterogeneous which hampers classical classification algorithms. Some researchers have recently modified the popular KNN algorithm as a solution, where they handle incompleteness by imputation and heterogeneity by converting categorical data into numbers. In this article, we introduce a novel KNN variant (KNNV) algorithm that provides better results as demonstrated by thorough experimental work. We employ rough set theoretic techniques to handle both incompleteness and heterogeneity, as well as to find an ideal value for K. The KNNV algorithm takes an incomplete, heterogeneous dataset, containing medical records of people, and identifies those cases with COVID-19. We use in the process two popular distance metrics, Euclidean and Mahalanobis, in an effort to widen the operational scope. The KNNV algorithm is implemented and tested on a real dataset from the Italian Society of Medical and Interventional Radiology. The experimental results show that it can efficiently and accurately classify COVID-19 cases. It is also compared to three KNN derivatives. The comparison results show that it greatly outperforms all its competitors in terms of four metrics: precision, recall, accuracy, and F-Score. The algorithm given in this article can be easily applied to classify other diseases. Moreover, its methodology can be further extended to do general classification tasks outside the medical field. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the proportion of clinical scenarios covered by EURO-2000 Guidelines and ESR iGuide, and assess compliance with both guidelines. Methods: The clinical indication on archived request forms for head, chest, abdomen-pelvis, and spine CT examinations performed in three hospitals in January 2018 was retrospectively matched with EURO-2000 Guidelines and ESR iGuide. For clinical scenarios addressed in the guidelines, the compliance with the guidelines was assessed. Analysis was performed on pooled data from the three centres and further stratified by centre, body region, and prescriber's specialisation. The differences in categorical data distributions between centres, body regions, and prescribers' specialisations were assessed with paired McNemar's χ2 tests. Results: A total of 6,812 requests for 7,217 CT examinations were analysed. Sixty-five percent of clinical situations that lead to prescribing CT examinations were addressed in EURO-2000 Guidelines compared with 81% for ESR iGuide. Proportions of clinical scenarios covered by the guidelines were statistically different between centres and body regions (p < 0.001) and varied according to prescribers' specialisations (p ranging from < 0.001 to 0.531). Both EURO-2000 Guidelines and ESR iGuide encompassed more clinical scenarios in certain body regions, favouring, e.g. spine and head over abdomen and chest. The proportion of "unjustified examinations" was greater according to EURO-2000 Guidelines (46%) than ESR iGuide (23%) (p < 0.001). Conclusions: Both EURO-2000 Guidelines and ESR iGuide do not address numerous common clinical scenarios. The proportions of scenarios addressed differ according to the centre, body region, and prescribers' specialisation. Any estimation of compliance with referral guidelines is therefore of relative significance. Key Points: • ESR iGuide performs better than earlier EURO-2000 Guidelines for the coverage of all possible clinical scenarios leading to CT referrals. • Differences in coverage of clinical scenarios by both referral guidelines are observed for different body regions and/or prescribers' subspecialties. • As referral guidelines are incomplete, any estimation of justified or unjustified CT requests is of relative significance. [ABSTRACT FROM AUTHOR]

Objective: Even though lumbosacral transitional vertebrae (LSTV) are one of the most common congenital anomalies of the spine, their effect on surrounding soft tissues is not well-studied. We therefore aimed at analyzing the association between LSTV and changes in volume, mass, symmetry, and degeneration of lumbar and trunk muscles. Materials and methods: Abdomen–pelvis CT scans were analyzed in patients with LSTV and a matched control group. LSTV were classified according to the Castellvi classification. Muscles were segmented from the remaining soft tissue and their cross-sectional area and volume were examined at five defined levels. Threshold segmentation was used to differentiate between muscle fibers and fat tissue. Matched pairs were compared using Wilcoxon rank sum tests. For comparison of categorical data, chi-squared tests were performed and for associations between the degree of fusion and muscle size and degeneration, Spearman's correlation coefficients were calculated. Inter- and intrarater reliabilities were evaluated by computing intraclass correlation coefficients. Results: Forty-six patients with LSTV and 46 controls were included. Muscle volume of the paraspinal and trunk muscles was significantly lower (707.0 cm3 vs. 809.7 cm3, p < 0.001) and fatty muscle changes were significantly increased in all but the caudal paravertebral muscles of LSTV patients (M. psoas p < 0.04, M. quadratus lumborum p < 0.001, paravertebral muscles p = 0.011, M. rectus abdominis p < 0.001, M. obliquus abdominis p < 0.001). Correlations between the degree of Castellvi classification and muscle volume were significant (p = 0.001). Conclusion: LSTV are associated with a reduction in muscle volume and an increase in muscle degeneration of both lumbar and trunk muscles. [ABSTRACT FROM AUTHOR]

Throughout this article, we fix a group G and a commutative ring k . This is an exposition on 2-equivalences between a 2-category of small k -categories with pseudoG-actions and a 2-category of G-graded small k -categories, which generalizes (Asashiba in Appl Categor Sturct 25(8):3278–3296, 2017). This article is a translation of some parts of Ch. 4 and 5 in the book (Asashiba in Categories and representation theory, focused on 2-categorical covering theory, SGC library 155, Saiensu-sha, 2019) in Japanese. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the association between the severity and extent of periodontitis and arterial stiffness using the cardio-ankle vascular index (CAVI). Materials and methods: A cross-sectional study of 2888 Electricity Generation Authority of Thailand (EGAT) employees aged 44–78 years was conducted. The severity of periodontitis was evaluated based on mean clinical attachment level (CAL). The percentage of sites with CAL ≥ 5 mm was used to divide the extent of periodontitis into healthy (0%), localized (> 0–< 30%), and generalized (≥ 30%). The CAVI value, a novel blood pressure-independent arterial stiffness parameter, was analyzed as both continuous and categorical data (low: < 9 or high: ≥ 9). Regression analysis was used to estimate the level of association. Results: The participants demonstrated a mean CAL, % sites with CAL ≥ 5 mm, and a CAVI value of 3.2 ± 1.2 mm, 16.0 ± 20.8%, and 8.24 ± 1.12, respectively. Higher mean CAVI was observed with greater mean CAL and % sites with CAL ≥ 5 mm. The mean CAVI of the healthy, localized, and generalized periodontitis groups were 8.01 ± 1.11, 8.22 ± 1.12, and 8.51 ± 1.04, respectively (p < 0.01). Linear and logistic regression analysis demonstrated a significant relationship between CAVI and all periodontal variables with β = 0.004–0.17 and OR = 1.01–1.58, respectively. Conclusions: There is a significant dose-dependent association between the severity and extent of periodontitis and arterial stiffness measured by CAVI in Thai adults. Clinical relevance: Preventing arterial stiffness, an early sign of cardiovascular events, by controlling the emerging risk factors, such as periodontitis, might have a high impact on health promotion. [ABSTRACT FROM AUTHOR]

We explore a non-abelian torsion theory in the category of preordered groups: the objects of its torsion-free subcategory are the partially ordered groups, whereas the objects of the torsion subcategory are groups (with the total order). The reflector from the category of preordered groups to this torsion-free subcategory has stable units, and we prove that it induces a monotone-light factorization system. We describe the coverings relative to the Galois structure naturally associated with this reflector, and explain how these coverings can be classified as internal actions of a Galois groupoid. Finally, we prove that in the category of preordered groups there is also a pretorsion theory, whose torsion subcategory can be identified with a category of internal groups. This latter is precisely the subcategory of protomodular objects in the category of preordered groups, as recently discovered by Clementino, Martins-Ferreira, and Montoli. [ABSTRACT FROM AUTHOR]

The aim of this paper is to exploit the structure of strongly continuous operator semigroups in order to formulate a categorical framework in which a fresh perspective can be applied to past operator theoretic results. In particular, we investigate the inverse-producing Arens extension for Banach algebras (Trans. Am. Math. Soc. 88:536–548, 1958) adapted for operators and operator semigroups by Batty and Geyer (J. Oper. Theory 78(2):473–500, 2017) in this new framework, asking and answering questions using categorical language. We demonstrate that the Arens extension defines an extension functor in this setting and that it forms an adjunction with the suitably defined forgetful functor. As a by-product of this categorical framework, we also revisit the work on Banach direct sums by Lachowicz and Moszyński (Semigroup Forum 93(1):34–70, 2016). This paper can be considered as a brief exploration of the triple interface between operator semigroups, Banach algebras, and category theory. [ABSTRACT FROM AUTHOR]

This paper introduces a method to generate conditional categorical simulations, given an ensemble of partially conditioned (or unconditional) categorical simulations derived from any simulation process. The proposed conditioning method relies on implicit functions (signed distance functions) for representing the categorical spatial variable of interest. Thus, the conditioning problem is reformulated in terms of signed distance functions. The proposed approach combines aspects of principal component analysis and Gibbs sampling to achieve the conditioning of the unconditional categorical realizations to the data. It is applied to synthetic and real-world datasets and compared to the traditional sequential indicator simulation. It appears that the proposed simulation technique is an effective method to generate conditional categorical simulations from a set of unconditional categorical simulations. [ABSTRACT FROM AUTHOR]

Purpose: Health-related quality of life (HRQoL) is assessed by self-administered questionnaires throughout the care process. Classically, two longitudinal statistical approaches were mainly used to study HRQoL: linear mixed models (LMM) or time-to-event models for time to deterioration/time until definitive deterioration (TTD/TUDD). Recently, an alternative strategy based on generalized linear mixed models for categorical data has also been proposed: the longitudinal partial credit model (LPCM). The objective of this article is to evaluate these methods and to propose recommendations to standardize longitudinal analysis of HRQoL data in cancer clinical trials. Methods: The three methods are first described and compared through statistical, methodological, and practical arguments, then applied on real HRQoL data from clinical cancer trials or published prospective databases. In total, seven French studies from a collaborating group were selected with longitudinal collection of QLQ-C30. Longitudinal analyses were performed with the three approaches using SAS, Stata and R software. Results: We observed concordant results between LMM and LPCM. However, discordant results were observed when we considered the TTD/TUDD approach compared to the two previous methods. According to methodological and practical arguments discussed, the approaches seem to provide additional information and complementary interpretations. LMM and LPCM are the most powerful methods on simulated data, while the TTD/TUDD approach gives more clinically understandable results. Finally, for single-item scales, LPCM is more appropriate. Conclusion: These results pledge for the recommendation to use of both the LMM and TTD/TUDD longitudinal methods, except for single-item scales, establishing them as the consensual methods for publications reporting HRQoL. [ABSTRACT FROM AUTHOR]

Purpose: To compare cervical vertebral anomalies and sella turcica bridging (STB) in different growth stages in orthodontic patients with different vertical skeletal growth patterns. Methods: Lateral cephalometric radiographs (LCR) of 270 patients in the preadolescent, adolescent, or postadolescent periods and having low angle [LA], normal angle [NA], or high-angle [HA] vertical skeletal growth patterns were evaluated retrospectively. STB was visualized using LCRs while evaluating the deficiency of ponticulus posticus (PP) and atlas posterior arch (PAA) associated with the atlas bone. The Pearson chi-square and Fisher's exact tests were used for categorical data and one-way ANOVA for numerical data. Results: The prevalence of fully calcified PP and STB increased from the preadolescent (PP, 10.0%; STB, 11.1%) to the postadolescent period (PP, 24.4; STB, 21.1%); they did not differ from vertical skeletal growth patterns (p > 0.05). The prevalence of PAA deficiency is significantly higher in individuals with LA (46.7%) than with other angles (NA, 27.8%; HA, 26.7%). The vertical skeletal growth pattern was significantly related to STB in the preadolescent period and PAA in the postadolescent period. Conclusions: Different anomalies during different growth periods correlate with the vertical skeletal growth pattern. It will be useful to evaluate a different anomaly according to the relevant growth period. [ABSTRACT FROM AUTHOR]

We consider the challenging task of evaluating the commercial viability of hydrocarbon prospects based on limited information, and in limited time. We investigate purely data-driven approaches to predicting key reservoir parameters and obtain a negative result: the information that is typically available for prospect evaluation and is suitable for data-based methods, cannot be used for the required predictions. We can show however that the same information is sufficient to produce a limited list of potentially similar well-explored reservoirs (known as analogues) that can support the prospect evaluation work of human geoscientists. We base the proposal of analogues on similarity measures on the data available about prospects. Technically, the challenge is to define suitable similarity measures on categorical data like depositional environment or rock types. Existing data-based similarity measures for categorical data do not perform well, since they do not take geological domain knowledge into account. We propose two novel similarity measures that use domain knowledge in the form of hierarchies on categorical values. Comparative evaluation shows that the semantic-based similarity measures outperform the existing data-driven approaches and are effective in comparison to the human analogue selection. [ABSTRACT FROM AUTHOR]

We disprove two (unpublished) conjectures of Kontsevich which state generalized versions of categorical Hodge-to-de Rham degeneration for smooth and for proper DG categories (but not smooth and proper, in which case degeneration is proved by Kaledin (in: Algebra, geometry, and physics in the 21st century. Birkhäuser/Springer, Cham, pp 99–129, 2017). In particular, we show that there exists a minimal 10-dimensional A ∞ -algebra over a field of characteristic zero, for which the supertrace of μ 3 on the second argument is non-zero. As a byproduct, we obtain an example of a homotopically finitely presented DG category (over a field of characteristic zero) that does not have a smooth categorical compactification, giving a negative answer to a question of Toën. This can be interpreted as a lack of resolution of singularities in the noncommutative setup. We also obtain an example of a proper DG category which does not admit a categorical resolution of singularities in the terminology of Kuznetsov and Lunts (Int Math Res Not 2015(13):4536–4625, 2015) (that is, it cannot be embedded into a smooth and proper DG category). [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study is to identify the clinical manifestations and laboratory findings of children with Kawasaki disease (KD) in different age groups and to recognize and treat KD in a timely manner. Methods: A total of 213 children with KD were divided into the following age groups: (1) infants, (2) toddlers, and (3) preschool age. Retrospective analysis of clinical data was performed among the groups. Categorical data were statistically compared by Chi-square analysis, and measurement data were compared using one-way ANOVA analysis. Results: Our study showed that (1) cough (40.5%), diarrhea (16.9%), and vomiting (8.5%) were also very common in KD patients. (2) Patients in the infant group more commonly developed cough and diarrhea, but were less frequently documented with lymphadenopathy and skin rash. (3) Elevation of platelets was more common in the infant group. When urine tests were compared among the three groups, the toddler group had a higher proportion of sterile pyuria, and infants younger than 1 year old had a lower proportion of proteinuria and positive urine ketones. Conclusion: Cough, diarrhea, vomiting, and sterile pyuria were very common in infant KD patients less than 1 year old. They should be noted in patients with suspected KD for earlier diagnosis and timely treatments. Key Points • Patients with Kawasaki disease (KD) in different age groups showed different clinical manifestations and laboratory findings. • Cough, diarrhea, vomiting, and sterile pyuria were very common in infant KD patients less than 1 year old. • Paying more attentions to respiratory, gastrointestinal, and urinary manifestations or abnormalities might be helpful for earlier diagnosis of KD, especially incomplete KD, though they were not list in the diagnostic criteria. [ABSTRACT FROM AUTHOR]

Individuals seek food assistance from both government and nongovernmental services. The theory of voluntary sector failure asserts that governments act where nonprofits fail. How, if at all, does this theoretical approach provide insight into basic food provision through food pantries? We conducted a single embedded case study of one network of food pantry programs (n = 298) in one county of approximately 3 million people in the southwest of the USA. We used a survey (n = 137) to measure programmatic and organizational capacity and, then, categorized capacity measures into the four failure categories identified in the theory of voluntary sector failure. We found moderate to strong evidence of failure in all of the categories; however, we also argue that these data do not necessarily support the theory of voluntary sector failure. Two key nuances are identified. [ABSTRACT FROM AUTHOR]

Distance-based techniques in detecting outliers appears to be an effective tool in both univariate and multivariate data. However, the effectiveness of the same is yet to be firmly established in categorical data as it poses challenges due to polarization of cell frequencies. The purpose of this paper is to evolve a new distance-based measure to detect outliers in two-dimensional contingency tables. The new distance measure based on pivotal element is evaluated through a comparison with other suitable distance measures from the literature for its performance. The consistency of the four distance measures is examined through a simulation study followed by the application to real datasets. [ABSTRACT FROM AUTHOR]

Artificial neural network is an information process system that simulates the structure and intelligent behavior of the brain based on the understanding of its organizational structure and operating mechanism. In order to deal with the recommendation task for online advertising, this paper proposes a special intelligent recommendation approach based on hybrid deep neural network. This approach integrating embedding mapping network, factorization machine, stacked denoising autoencoder and regression model, can effectively model complex categorical data, learn higher-order abstract features like the brain, and then classify them to achieve the purpose of precise recommendation, and can be well parallelized. Experimental results on the real dataset show that compared with the baseline models, the proposed approach has better performance in the face of scenarios containing a large number of complex categorical data. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: The urogynecology subspecialty relies on appropriate referrals from their referral base. We sought to provide guidance for optimizing appropriate referrals to urogynecology by comparing pre-referral characteristics between appropriate and inappropriate referrals. Methods: This retrospective cohort study examined predictors of appropriate urogynecology referrals. Appropriateness categorization was based upon pelvic floor disorder (PFD) symptoms and signs provided by the referring provider. Patients with both a PFD symptom and sign were considered "appropriate." Patients with neither a PFD symptom nor sign were considered "inappropriate." PFD symptoms were: vaginal bulge, voiding or defecatory dysfunction. PFD signs were: vaginal vault prolapse, urethral hypermobility, mesh/sling exposure, elevated post-void residual, positive standing stress test, abnormal urinalysis or urine culture-proven infection. Continuous and categorical data were analyzed with ANOVA and chi-square test, respectively. A logistic regression model to predict appropriateness was developed from variables identified from the bivariate analysis. Results: Bivariate predictors of an appropriate referral for 1716 study subjects were older age, prior overactive bladder medication use, MD/DO referrer source and OBGYN, urogynecology or urology referrer specialty. Our logistic regression model correctly classified referrals as appropriate in 93.6% of cases. Conclusions: Age, anti-cholinergic medication use, referrer source and specialty are pre-initial visit predictors of urogynecology referral appropriateness. The predictor-generated model was successful in predicting referral appropriateness. Potential bias from information transfer issues, lack of pre-referral evaluation and referring provider unfamiliarity with urogynecology are possible reasons for inappropriate referrals and potential areas for improvement. [ABSTRACT FROM AUTHOR]

Categorical attributes are ubiquitous in real-world collected data. However, such attributes lack a well-defined distance metric and cannot be directly manipulated per algebraic operations, so many data mining algorithms are unable to work directly on them. Learning an appropriate metric or an effective numerical embedding is very vital yet challenging, for categorical attributes with multi-view heterogeneous data characteristics. This paper proposes a novel multi-view heterogeneous fusion model (MVHF), which first captures basic coupling information for each view and then fuses these heterogeneous information from different views by multi-kernel metric learning, to measure the intrinsic distances between this type of categorical attributes; based on these measured distances, further, we use the manifold learning method to learn a high-quality numerical embedding for each categorical value. Experiments on 33 mixed data sets demonstrate that MVHF-enabled classification significantly enhances the performance, compared with state-of-the-art distance metrics or embedding competitors. [ABSTRACT FROM AUTHOR]

The condition of σ -completeness related to orthomodular lattices places an important role in the study of quantum probability theory. In the framework of algebras with infinitary operations, an equational theory for the category of σ -complete orthomodular lattices is given. In this structure, we study the congruences theory and directly irreducible algebras establishing an equational completeness theorem. Finally, a Hilbert style calculus related to σ -complete orthomodular lattices is introduced and a completeness theorem is obtained. [ABSTRACT FROM AUTHOR]

In this work, large-scale structural optimization problems involving non-ordinal categorical design variables and continuous variables are investigated. The aim is to minimize the weight of a structure with respect to cross-section areas, with materials and stiffening principles selection. First, the problem is formulated using a bi-level decomposition involving master and slave problems. The master problem is given by a first-order-like approximation that helps to drastically reduce the combinatorial explosion raised by the categorical variables. Continuous variables are handled in a slave problem solved using a gradient-based approach, where the categorical variables are driven by the master problem. The proposed algorithm is tested on three different structural optimization test cases. A comparison to state-of-the-art algorithms emphasize efficiency of the proposed algorithm in terms of the optimum quality, the computation cost, and the scaling with respect to the problem dimension. [ABSTRACT FROM AUTHOR]

In recent years, the clustering ensembles emerged as a problem solver for extracting the data points into clusters in an efficient way. However, still clustering poses a serious issue due to the presence of imperfect information while partitioning the data into clusters. This creates a serious issue in creating an efficient cluster with cluster ensembles. In this paper, we propose a solution to solve the degradation in clustering during data partitioning. The initial clusters are generated using firefly algorithm. A linked cluster ensemble approach uses similarity measurement using multi-viewpoint and weighted triple quality using entropy measurements that ensembles the data points into clusters. This avoids the problem of local optimum and avoids the issues arise from high-dimensional datasets and improve the quality of clustering. Here, the data partitioning is done with bipartite spectral algorithm and similarity measurement. Finally, the artificial neural network is used to generate classified results from the optimized clustered datasets. The experimental results are carried out over UCI repository datasets and the results show that the proposed method attains an effective ensemble clustering with higher clustering accuracy than the conventional ones. [ABSTRACT FROM AUTHOR]

Background: When children with attention-deficit/hyperactivity disorder (ADHD) are treated with stimulant medication, the dose is established clinically by dose adjustment over time. Little is known about children who are not adequately treated when they reach a designated maximum dose, or the consequences of exceeding this dose.Objective: The aim of this study was to determine the characteristics of and side effects observed in children optimised to high dose (HD) versus regular dose (RD) stimulants.Method: Children treated by one paediatrician (AP) in Western Sydney, Australia with HD stimulants (n = 52) were identified using an electronic database; controls on RD stimulant (n = 118) were matched by prescription date with the cases' first HD prescription. HD was defined as methylphenidate > 2 mg/kg/day or > 108 mg/day; dexamphetamine > 1 mg/kg/day or > 50 mg/day; lisdexamfetamine > 70 mg/day. In all children, the dose was adjusted over time to optimise the clinical response. Clinical characteristics, anthropometric measures, reported side effects and reasons for dose changes were extracted from the clinical charts by LR, VS and CS. The HD and RD cohorts were compared using chi-square for categorical data and t tests for continuous data.Results: The HD cohort included more boys (88% vs 75%, p = 0.041) and more oppositional defiant disorder (83% vs 55%, p = 0.001). They started stimulants younger (6.40 ± 1.67 vs 8.28 ± 2.77 years, p < 0.001) and had more growth attenuation (Δ height z-score - 0.41 ± 0.55 vs - 0.09 ± 0.58, p = 0.001; Δ weight z-score  - 0.56 ± 0.82 vs - 0.18 ± 0.66, p = 0.002). The growth attenuation mainly occurred before the dose reached the HD range. Diminishing stimulant effectiveness was the commonest reason for a dose increase in either cohort, the most prominent recurring symptoms being persistent anger/aggression in the HD and poor concentration in the RD cohort. The commonest reason for dose reduction in the HD cohort was that a dose increase gave no added benefit; dose reduction or change of drug due to subdued/depressed behaviour was more frequent in RD children. Apart from growth attenuation, no serious complications were reported in the HD group.Conclusions: In this preliminary study, dose adjustment over time in some patients meant using higher doses than those generally recommended. These children experienced more growth attenuation but recorded no other significant treatment complications. Determining the dose purely on clinical grounds by careful dose adjustment over time appears reasonable, but more data on this issue is required to clarify the efficacy and tolerability of exceeding the recommended doses of stimulants when treating ADHD. [ABSTRACT FROM AUTHOR]

Purpose: Cigarettes have been demonstrated to be toxic to the pulmonary connective tissue by impairing the lung's ability to clear debris, resulting in infection and acute respiratory distress syndrome (ARDS). Approximately 8% of adolescents are smokers. We hypothesized that adolescent trauma patients who smoke have a higher rate of ARDS and pneumonia when compared to non-smokers.Methods: The Trauma Quality Improvement Program (2014-2016) was queried for adolescent trauma patients aged 13-17 years. Adolescent smokers were 1:2 propensity-score-matched to non-smokers based on age, comorbidities, and injury type. Data were analyzed using chi square for categorical data and Mann-Whitney U test for continuous data.Results: From 32,610 adolescent patients, 997 (3.1%) were smokers. After matching, 459 smokers were compared to 918 non-smokers. There were no differences in matched characteristics. Compared to non-smokers, smokers had an increased rate of pneumonia (3.1% vs. 1.1%, p = 0.01) but not ARDS (0.2% vs. 0%, p = 0.16). Compared to the non-smoking group, the smokers had a longer median total hospital length-of-stay (3 vs. 2 days, p = 0.01) and no difference in overall mortality (1.5% vs. 2.4%, p = 0.29).Conclusion: Smoking is associated with an increased rate of pneumonia in adolescent trauma patients. Future research should target smoking cessation and/or interventions to mitigate the deleterious effects of smoking in this population. [ABSTRACT FROM AUTHOR]

Studying the properties of almost ω-categorical quite o-minimal theories, we prove that the arbitrary families of pairwise weakly orthogonal nonalgebraic 1-types in these theories are orthogonal. We also establish the binarity of these theories. [ABSTRACT FROM AUTHOR]

Data sets to which clustering is applied may be homogeneous (numerical or categorical) or heterogeneous (numerical and categorical) in nature. Handling homogeneous data is easier than heterogeneous data. We propose a novel technique for identifying initial seeds for heterogeneous data clustering, through the introduction of a unique distance measure where the distance of the numerical attributes is scaled such that it is comparable to that of categorical attributes. The proposed initial seed selection algorithm ensures selection of initial seed points from different clusters of the clustering solution which are then given as input to the modified K-means clustering algorithm along with the data set. This technique is independent of any user-defined parameter and thus can be easily applied to clusterable data sets with mixed attributes. We have also modified the K-means clustering algorithm to handle mixed attributes by incorporating our novel distance measure to handle numerical data and assigned the value one or zero when categorical data is dissimilar or similar. Finally, a comparison has been made with existing algorithms to bring out the significance of our approach. We also perform a statistical test to evaluate the statistical significance of our proposed technique. [ABSTRACT FROM AUTHOR]

Model-based clustering of human population genomic data, composed of 1,318 individuals arisen from western Central Africa and 160,470 markers, is considered. This challenging analysis leads us to develop a new methodology for variable selection in clustering. To explain the differences between subpopulations and to increase the accuracy of the estimates, variable selection is done simultaneously to clustering. We proposed two approaches for selecting variables when clustering is managed by the latent class model (i.e., mixture considering independence within components). The first method simultaneously performs model selection and parameter inference. It optimizes the Bayesian Information Criterion with a modified version of the standard expectation–maximization algorithm. The second method performs model selection without requiring parameter inference by maximizing the Maximum Integrated Complete-data Likelihood criterion. Although the application considers categorical data, the proposed methods are introduced in the general context of mixed data (data composed of different types of features). As the first step, the interest of both proposed methods is shown on simulated and several benchmark real data. Then, we apply the clustering method to the human population genomic data which permits to detect the most discriminative genetic markers. The proposed method implemented in the R package VarSelLCM is available on CRAN. [ABSTRACT FROM AUTHOR]

We develop a general framework for c-vectors of 2-Calabi–Yau categories, which deals with cluster tilting subcategories that are not reachable from each other and contain infinitely many indecomposable objects. It does not rely on iterative sequences of mutations. We prove a categorical (infinite-rank) generalization of the Nakanishi–Zelevinsky duality for c-vectors and establish two formulae for the effective computation of c-vectors—one in terms of indices and the other in terms of dimension vectors for cluster tilted algebras. In this framework, we construct a correspondence between the c-vectors of the cluster categories C (A ∞) of type A ∞ due to Igusa–Todorov and the roots of the Borel subalgebras of sl ∞ . Contrary to the finite dimensional case, the Borel subalgebras of sl ∞ are not conjugate to each other. On the categorical side, the cluster tilting subcategories of C (A ∞) exhibit different homological properties. The correspondence builds a bridge between the two classes of objects. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to investigate the characteristics and outcome of systemic lupus erythematosus (SLE) among elderly-onset patients. Methods: This study included 575 SLE patients managed at Cairo, Alexandria, and Helwan universities from August 2014 to 2018: of whom 49 (8.5%), 420 (73%), and 106 (18.4%) were elderly- (> 50 years), adult- (17–50 years), and juvenile- (≤ 16 years) onset patients, respectively. Cumulative characteristics were recorded. Disease activity at the last visit was investigated through the Systemic Lupus Erythematosus Disease Activity Index-2K (SLEDAI-2K), whereby lupus low disease activity (LLDA) was defined as a SLEDAI-2K score ≤ 4. The disease outcome was assessed through investigating disease damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI)) and the prevalence of mortality. Quantitative and categorical data were compared using Kruskal–Wallis and Mann–Whitney tests, and chi-square (χ2) test, respectively. Results: Late-onset SLE (LSLE) patients demonstrated the lowest prevalence of constitutional and mucocutaneous manifestations (p < 0.001), serositis (p = 0.006), nephritis (p < 0.001), neuropsychiatric involvement (p < 0.001), and hypocomplementinemia (p < 0.001), but showed the highest prevalence of comorbidities and multimorbidity (comorbidities ≥ 2) (p < 0.001), and positive anti-ds DNA antibodies (p < 0.001). Elderly-onset patients demonstrated the lowest SLEDAI-2K and SDI scores, achieved LLDA the most (p < 0.001), and developed any damage (SDI ≥ 1) the least (p < 0.001). The prevalence of mortality was comparable across the three age groups (p = 0.6). Conclusions: Late-onset SLE patients (8.5%) showed the lowest prevalence of major organ involvement and the highest prevalence of comorbidities, and demonstrated more favorable disease activity and damage indices. Key Points • The disease characteristics and outcome among LSLE patients are characterized by being controversial, with studies from the Middle East being limited. Our cohort constituted of 8.5% elderly-onset SLE patients—who were characterized by the lowest prevalence of major organ involvement and the lowest activity and damage indices—making the disease pattern more favorable in this age group, despite being characterized by the highest prevalence of comorbidities. [ABSTRACT FROM AUTHOR]

Multiple-point statistics (MPS) is a simulation technique allowing to generate images that reproduce the spatial features present in a training image (TI). MPS algorithms consist in sequentially filling a simulation grid such that patterns around the simulated values come from the TI. Following this principle, joint simulations of multiple variables can be handled and complex heterogeneous fields can be generated. However, inconsistent patterns are often found in the results and some spatial features can be difficult to reproduce. In this paper, a new MPS algorithm based on a multi-resolution representation of the TI is proposed to enhance the quality of the realizations. The method consists in first building a pyramid of images from the TI by successive convolution using Gaussian-like kernels. Secondly, a MPS simulation is done at the lowest resolution level. Then, the result is expanded to the next level of resolution (one rank higher) and used as a conditioning variable for a joint MPS simulation at that level. This last step is repeated up to the initial resolution, where the final simulation is retrieved. The method is implemented in the DeeSse code based on the direct sampling algorithm. Most of the features provided by the direct sampling (conditioning to hard data, uni- or multi-variate simulation of categorical and continuous variables, scaling and rotation of the training structures) are compatible with the proposed method and the usability is maintained. Finally, various examples show that in most of the situations, combining Gaussian pyramids with MPS allows to get results of better quality and in less time compared to direct MPS simulations. [ABSTRACT FROM AUTHOR]

Purpose: Little is known of how children seek health information. This study evaluates online health information (OHI) seeking behaviours in adolescents undergoing major elective surgical procedures and compares responses within parent-child dyads.Methods: With institutional approval, we prospectively surveyed parents of children admitted to our institution for major elective operations between November 2017 and November 2018, using convenience sampling. Patients aged 12 years and above were also invited. Each respondent completed an anonymized modification of a previously published survey on Internet usage. Chi squared tests were used for categorical data, with significance at P value < 0.05.Results: Ninety-one parents and 19 patients (median age 15 years, range 12-18) responded, with 13 parent-child pairs. Daily Internet access was reported by 84 (93%) parents and 18 (95%) children, but OHI was sought in 77% of parents and 74% of children. Six (32%) children could not name their admitting condition, compared to 10 (11%) parents. Nine (50%) children consulted family and friends for information compared to 27 (30%) parents. Parents were more likely to access hospital websites (n = 15, 44%) compared to no children (p = 0.01), while most children (n = 7, 70%) accessed non-health websites (e.g. Wikipedia). In the 13 parent-child pairs, only one parent accurately assessed what their child understood of their condition. Most patients (63.6%) did not understand the aspects of their condition that their parents deemed important.Conclusions: This study highlights the differences in parental and child behaviours. Children are equally important to include when counselling. Surgeons can guide both parties to reliable Internet sources for health information. [ABSTRACT FROM AUTHOR]