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Author(s): Dewey, Kathryn G; Wessells, K Ryan; Arnold, Charles D; Prado, Elizabeth L; Abbeddou, Souheila; Adu-Afarwuah, Seth; Ali, Hasmot; Arnold, Benjamin F; Ashorn, Per; Ashorn, Ulla; Ashraf, Sania; Becquey, Elodie; Bendabenda, Jaden; Brown, Kenneth H; Christian, Parul; Colford, John M; Dulience, Sherlie JL; Fernald, Lia CH; Galasso, Emanuela; Hallamaa, Lotta; Hess, Sonja Y; Humphrey, Jean H; Huybregts, Lieven; Iannotti, Lora L; Jannat, Kaniz; Lartey, Anna; Port, Agnes Le; Leroy, Jef L; Luby, Stephen P; Maleta, Kenneth; Matias, Susana L; Mbuya, Mduduzi NN; Mridha, Malay K; Nkhoma, Minyanga; Null, Clair; Paul, Rina R; Okronipa, Harriet; Ouedraogo, Jean-Bosco; Pickering, Amy J; Prendergast, Andrew J; Ruel, Marie; Shaikh, Saijuddin; Weber, Ann M; Wolff, Patricia; Zongrone, Amanda; Stewart, Christine P | Abstract: ABSTRACTBackgroundMeta-analyses have demonstrated that small-quantity lipid-based nutrient supplements (SQ-LNS) reduce stunting and wasting prevalence among infants and young children. Identification of subgroups who benefit most from SQ-LNS may facilitate program design.ObjectiveOur objective was to identify study-level and individual-level modifiers of the effect of SQ-LNS on child growth outcomes.MethodsWe conducted a two-stage meta-analysis of individual participant data from 14 randomized controlled trials of SQ-LNS provided to children 6 to 24 months of age in low- and middle-income countries (n=37,066). We generated study-specific and subgroup estimates of SQ-LNS vs. control and pooled the estimates using fixed-effects models, with random-effects models as sensitivity analyses. We used random effects meta-regression to examine study-level effect modifiers. Heterogeneity was assessed using I2 and Tau2 statistics. Sensitivity analyses were conducted to examine whether results differed depending on inclusion criteria for arms within trials and types of comparisons.ResultsSQ-LNS provision decreased stunting (length-for-age z-score l −2) by 12% (relative reduction), wasting (weight-for-length (WLZ) z-score l −2) by 14%, low mid-upper arm circumference (MUAC l 125 mm or MUACZ l −2) by 18%, acute malnutrition (WLZ l −2 or MUAC l 125 mm) by 14%, underweight (weight-for-age z-score l −2) by 13%, and small head size (head-circumference z-score l −2) by 9%. Effects of SQ-LNS on growth outcomes generally did not differ by study-level characteristics including region, stunting burden, malaria prevalence, sanitation, water quality, duration of supplementation, frequency of contact or average reported compliance with SQ-LNS. Effects of SQ-LNS on stunting, wasting, low MUAC and small head size were greater among girls than among boys; effects on stunting, underweight and low MUAC were greater among later-born (vs. first-born) children; and effects on wasting and acute malnutrition were greater among children in households with improved (vs. unimproved) sanitation. Results were similar across sensitivity analyses.ConclusionsThe positive impact of SQ-LNS on growth is apparent across a wide variety of study-level contexts. Policy-makers and program planners should consider including SQ-LNS in the mix of interventions to prevent both stunting and wasting. This study was registered at www.crd.york.ac.uk/PROSPERO as CRD42019146592.

International audience; Background Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is caused by anti-ADAMTS13 autoantibodies inducing a severe deficiency of ADAMTS13. Epitope mapping studies on samples obtained during acute iTTP episodes have shown that the iTTP immune response is polyclonal, with almost all patients having autoantibodies targeting the spacer domain of ADAMTS13.Objectives To identify the immunogenic hotspots in the spacer domain of ADAMTS13.Patients/methods A library of 11 full-length ADAMTS13 spacer hybrids was created in which amino acid regions of the spacer domain of ADAMTS13 were exchanged by the corresponding region of the spacer domain of ADAMTS1. Next, the full-length ADAMTS13 spacer hybrids were used in enzyme-linked immunosorbent assay to epitope map anti-spacer autoantibodies in 138 samples from acute and remission iTTP patients.Results Sixteen different anti-spacer autoantibody profiles were identified with a similar distribution in acute and remission patients. There was no association between the anti-spacer autoantibody profiles and disease severity. Almost all iTTP samples contained anti-spacer autoantibodies against the following three regions: amino acid residues 588-592, 602-610, and 657-666 (hybrids E, G, and M). Between 31% and 57% of the samples had anti-spacer autoantibodies against amino acid regions 572-579, 629-638, 667-676 (hybrids C, J, and N). In contrast, none of the samples had anti-spacer autoantibodies against amino acid regions 556-563, 564-571, 649-656, and 677-685 (hybrids A, B, L, and O).Conclusion We identified three hotspot regions (amino acid regions 588-592, 602-610, and 657-666) in the spacer domain of ADAMTS13 that are targeted by anti-spacer autoantibodies found in a large cohort of iTTP patients.

Author(s): Wessells, K Ryan; Arnold, Charles D; Stewart, Christine P; Prado, Elizabeth L; Abbeddou, Souheila; Adu-Afarwuah, Seth; Arnold, Benjamin F; Ashorn, Per; Ashorn, Ulla; Becquey, Elodie; Brown, Kenneth H; Byrd, Kendra A; Campbell, Rebecca K; Christian, Parul; Fernald, Lia CH; Fan, Yue-Mei; Galasso, Emanuela; Hess, Sonja Y; Huybregts, Lieven; Jorgensen, Josh M; Kiprotich, Marion; Kortekangas, Emma; Lartey, Anna; Le Port, Agnes; Leroy, Jef L; Lin, Audrie; Maleta, Kenneth; Matias, Susana L; Mbuya, Mduduzi NN; Mridha, Malay K; Mutasa, Kuda; Naser, Abu Mohd; Paul, Rina R; Okronipa, Harriet; Ouedraogo, Jean-Bosco; Pickering, Amy J; Rahman, Mahbubur; Schulze, Kerry; Smith, Laura E; Weber, Ann M; Zongrone, Amanda; Dewey, Kathryn G | Abstract: ABSTRACTBackgroundSmall-quantity lipid-based nutrient supplements (SQ-LNS) have been shown to reduce the prevalence of anemia and iron deficiency among infants and young children, but effects on other micronutrients are less well known. Identifying subgroups who may experience greater benefits from SQ-LNS, or who are more likely to respond to the intervention, may facilitate the development of public health policies and programs.ObjectiveOur objective was to identify study-level and individual-level modifiers of the effect of SQ-LNS on child hematological and micronutrient status outcomes.MethodsWe conducted a two-stage meta-analysis of individual participant data from 13 randomized controlled trials of SQ-LNS provided to children 6 to 24 months of age in low- and middle-income countries (n = 15,946). Outcomes were hemoglobin (Hb), inflammation-adjusted plasma ferritin, soluble transferrin receptor, zinc, retinol and retinol binding protein (RBP), and erythrocyte zinc protoporphyrin, and respective dichotomous outcomes indicative of anemia and micronutrient deficiency. We generated study-specific estimates of SQ-LNS vs. control, including main effects and subgroup estimates for individual-level effect modifiers, and pooled the estimates using fixed-effects models. We used random effects meta-regression to examine potential study-level effect modifiers.ResultsProvision of SQ-LNS decreased the prevalence of anemia (Hb l 110 g/L) by 16% (relative reduction), iron deficiency (plasma ferritin l 12 µg/L) by 56% and iron deficiency anemia (IDA; Hb l 110 g/L and plasma ferritin l 12 µg/L) by 64%. We observed positive effects of SQ-LNS on hematological and iron status outcomes within all subgroups of the study-level and individual-level effect modifiers, but effects were larger in certain subgroups. For example, effects of SQ-LNS on anemia and iron status were greater in trials that provided SQ-LNS for g 12 months and provided 9 mg/d vs. l 9 mg iron/d, and among later-born (vs. first-born) children. There was no effect of SQ-LNS on plasma zinc or retinol, but there was a 7% increase in plasma RBP and a 56% reduction in vitamin A deficiency (RBP l 0.70 µmol/L), with little evidence of effect modification by individual-level characteristics.ConclusionsSQ-LNS provided to infants and young children 6-24 months of age can substantially reduce the prevalence of anemia, iron deficiency, and IDA across a range of individual, population and study design characteristics. Policy-makers and program planners should consider SQ-LNS within intervention packages to prevent anemia and iron deficiency. This study was registered at www.crd.york.ac.uk/PROSPERO as CRD42020156663.

One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge Graphs: New Directions for Knowledge Representation on the Semantic Web" and described in its report is that of a: "Public FAIR Knowledge Graph of Everything: We increasingly see the creation of knowledge graphs that capture information about the entirety of a class of entities. [...] This grand challenge extends this further by asking if we can create a knowledge graph of "everything" ranging from common sense concepts to location based entities. This knowledge graph should be "open to the public" in a FAIR manner democratizing this mass amount of knowledge." Although linked open data (LOD) is one knowledge graph, it is the closest realisation (and probably the only one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides a unique testbed for experimenting and evaluating research hypotheses on open and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing evolution and long term preservation. We want to investigate this problem, that is to understand what preserving and supporting the evolution of KGs means and how these problems can be addressed. Clearly, the problem can be approached from different perspectives and may require the development of different approaches, including new theories, ontologies, metrics, strategies, procedures, etc. This document reports a collaborative effort performed by 9 teams of students, each guided by a senior researcher as their mentor, attending the International Semantic Web Research School (ISWS 2019). Each team provides a different perspective to the problem of knowledge graph evolution substantiated by a set of research questions as the main subject of their investigation. In addition, they provide their working definition for KG preservation and evolution.

Conjoint measurement studies binary relations defined on product sets and investigates the existence and uniqueness of numerical representations of such relations. It has proved to be quite a powerful tool to analyze and compare MCDM techniques designed to build a preference relation between multiattributed alternatives and has been an inspiring guide to many assessment protocols. These MCDM techniques lead to a relative evaluation model of the alternatives through a preference relation. Such models are not always appropriate to build meaningful recommendations. This has recently lead to the development of MCDM techniques aiming at building evaluation models having a more absolute character. In such techniques, the output of the analysis is, most often, a partition of the set of alternatives into several ordered categories defined with respect to outside norms, e.g., separating “Attractive” and “Unattractive” alternatives. In spite of their interest, the theoretical foundations of such MCDM techniques have not been much investigated. The purpose of this paper is to contribute to this analysis. More precisely, we show how to adapt classic conjoint measurement results to make them applicable for the study of such MCDM techniques. We concentrate on additive models. Our results may be seen as an attempt to provide an axiomatic basis to the well-known UTADIS technique that sorts alternatives using an additive value function model. Keywords: Decision with multiple attributes, Sorting, Conjoint measurement, UTADIS. La théorie du mesurage conjoint étudie la question de la représentation numérique d'une relation binaire définie sur un produit cartésien. Cette théorie s'est révélée très utile pour comparer et analyser diverses techniques d'aide multicritère à la décision. Elle a également été la source de nombreux protocoles d'élicitation. Les techniques d'aide à la décision utilisant une relation binaire comparant des actions évaluées sur plusieurs attributs conduisent, en général, à des modèles d'évaluation ayant un caractère relatif. Or, de tels modèles ne sont pas toujours adaptés pour bâtir une prescription pertinente. Ceci a conduit au développement de techniques multicritères conduisant à des modèles d'évaluation ayant un caractère plus absolu. Dans ces techniques, le résultat se présente généralement sous la forme d'une aectation des actions à diverses catégories ordonnées, ces catégories étant définies par rapport à des normes indépendantes des actions à évaluer. On pourra, par exemple, séparer les actions satisfaisantes de celles étant insatisfaisantes. En dépit de leur intérêt, les fondements théoriques de telles méthodes ont été peu étudiés. L'objectif de cet article est de contribuer à cette étude. Plus précisément, on montre comment adapter les résultats classiques du mesurage conjoint pour couvrir le cas de catégories ordonnées. On étudie plus spécifiquement le cas de représentations additives. Ce travail peut alors être vu comme une tentative de donner à la méthode UTADIS une base théorique solide. Mots-clés: Analyse multicritère, Tri, Mesurage conjoint, UTADIS.

A double $2$-$(v,k,2 \lambda)$ design is a design which is reducible into two $2$-$(v,k,\lambda)$ designs. It is called uniquely reducible if it has, up to equivalence, only one reduction. We present properties of uniquely reducible double designs which show that their total number can be determined if only the designs with non-trivial automorphisms are classified with respect to their automorphism group. As an application, after proving that a reducible $2$-$(21,5,2)$ design is uniquely reducible, we establish that the number of all reducible $2$-$(21,5,2)$ designs is $1 746 461 307$.

The generalized quadrangle $Q(4,q)$ arising from the parabolic quadric in $PG(4,q)$ always has an ovoid. It is not known whether a minimal blocking set of size smaller than $q^2 + q$ (which is not an ovoid) exists in $Q(4,q)$, $q$ odd. We present results on smallest blocking sets in $Q(4,q)$, $q$ odd, obtained by a computer search. For $q = 5,7,9,11$ we found minimal blocking sets of size $q^2 + q - 2$ and we discuss their structure. By an exhaustive search we excluded the existence of a minimal blocking set of size $q^2 + 3$ in $Q(4,7)$.

Research Group on Combinatorial Algorithms and Algorithmic Graph Theory, Department of Applied MathematicsandComputerScience,GhentUniversity,Krijgslaan281–S9,B–9000Ghent,Belgium. email: Joost.Winne@ugent.be,Veerle.Fack@ugent.beBefore this work, at least 762 inequivalent Hadamard matrices of order 36 were known. We found 7238 Hadamardmatrices of order 36 and 522 inequivalent [72,36,12] double-even self-dual codes which are obtained from all 2-(35,17,8) designs with an automorphism of order 3 and 2 fixed points and blocks.Keywords: Hadamard designs, double-even self-dual codes