scholarly journals Tractable Fragments of Datalog with Metric Temporal Operators

2020 ◽  
Author(s):  
Przemysław A. Wałęga ◽  
Bernardo Cuenca Grau ◽  
Mark Kaminski ◽  
Egor V. Kostylev
Keyword(s):  
Rational Numbers ◽  
Data Complexity ◽  
The Core ◽  
Core Fragment

We study the data complexity of reasoning for several fragments of MTL - an extension of Datalog with metric temporal operators over the rational numbers. Reasoning in the full MTL language is PSPACE-complete, which handicaps its application in practice. To achieve tractability we first study the core fragment, which disallows conjunction in rule bodies, and show that reasoning remains PSPACE-hard. Intractability prompts us to also limit the kinds of temporal operators allowed in rules, and we propose a practical core fragment for which reasoning becomes TC0-complete. Finally, we show that this fragment can be extended by allowing linear conjunctions in rule bodies, where at most one atom can be intensional (IDB); we show that the resulting fragment is NL-complete, and hence no harder than plain linear Datalog.

scholarly journals Querying and Repairing Inconsistent Prioritized Knowledge Bases: Complexity Analysis and Links with Abstract Argumentation

2020 ◽  
Author(s):  
Meghyn Bienvenu ◽  
Camille Bourgaux
Keyword(s):  
Complexity Analysis ◽  
Knowledge Bases ◽  
Data Complexity ◽  
The Core ◽  
Inconsistency Handling ◽  
Definition Of ◽  
Priority Relation ◽  
Inconsistent Database ◽  
The Relationship ◽  
Computational Properties

In this paper, we explore the issue of inconsistency handling over prioritized knowledge bases (KBs), which consist of an ontology, a set of facts, and a priority relation between conflicting facts. In the database setting, a closely related scenario has been studied and led to the definition of three different notions of optimal repairs (global, Pareto, and completion) of a prioritized inconsistent database. After transferring the notions of globally-, Pareto- and completion-optimal repairs to our setting, we study the data complexity of the core reasoning tasks: query entailment under inconsistency-tolerant semantics based upon optimal repairs, existence of a unique optimal repair, and enumeration of all optimal repairs. Our results provide a nearly complete picture of the data complexity of these tasks for ontologies formulated in common DL-Lite dialects. The second contribution of our work is to clarify the relationship between optimal repairs and different notions of extensions for (set-based) argumentation frameworks. Among our results, we show that Pareto-optimal repairs correspond precisely to stable extensions (and often also to preferred extensions), and we propose a novel semantics for prioritized KBs which is inspired by grounded extensions and enjoys favourable computational properties. Our study also yields some results of independent interest concerning preference-based argumentation frameworks.

scholarly journals False-Negative Results in Point-of-Care Qualitative Human Chorionic Gonadotropin (hCG) Devices Due to Excess hCGβ Core Fragment

2009 ◽  
Vol 55 (7) ◽  
pp. 1389-1394 ◽  
Author(s):  
Ann M Gronowski ◽  
Mark Cervinski ◽  
Ulf-Håkan Stenman ◽  
Alison Woodworth ◽  
Lori Ashby ◽  
...  
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Point Of Care ◽  
False Negative ◽  
The Core ◽  
Core Fragment ◽  
Negative Results ◽  
False Negative Results ◽  
Positive Results ◽  
Urine Specimens

Abstract Background: During pregnancy, human chorionic gonadotropin (hCG) immunoreactivity in urine consists of intact hCG as well as a number of hCG variants including the core fragment of hCGβ (hCGβcf). We identified 3 urine specimens with apparent false-negative results using the OSOM® hCG Combo Test (Genzyme Diagnostics) qualitative hCG device and sought to determine whether an excess of 1 of the fragments or variants might be the cause of the interference. Methods: We measured concentrations of hCG variants in the urine from 3 patients with apparent false-negative hCG results. Purified hCG variants were added to urines positive for hCG and tested using the OSOM, ICON® 25 hCG (Beckman Coulter), and hCG Combo SP® Brand (Cardinal Health) devices. Results: Dilution of these 3 urine samples resulted in positive results on the OSOM device. Quantification of hCG variants in each of the 3 patient urine specimens demonstrated that hCGβcf occurred in molar excess of intact hCG. Addition of purified hCGβcf to hCG-positive urines caused false-negative hCG results using the OSOM and ICON qualitative urine hCG devices. Conclusions: Increased concentrations of hCGβcf can cause false-negative results on the OSOM and ICON qualitative urine hCG devices. .

Concentrations of Human Choriogonadotropin, Its β-Subunit, and the Core Fragment of the β-Subunit in Serum and Urine of Men and Nonpregnant Women

1992 ◽  
Vol 38 (10) ◽  
pp. 1981-1987 ◽  
Author(s):  
H Alfthan ◽  
C Haglund ◽  
J Dabek ◽  
U H Stenman
Keyword(s):  
Urine Samples ◽  
Reference Ranges ◽  
Β Subunit ◽  
Serum Samples ◽  
Reference Limit ◽  
The Core ◽  
Core Fragment ◽  
Human Choriogonadotropin ◽  
Beta Hcg ◽  
Serum And Urine

Abstract Sensitive, specific time-resolved immunofluorometric assays were used to measure the concentrations of human choriogonadotropin (hCG), free beta-subunit (beta-hCG), and the core fragment of beta-hCG (c beta-hCG) in serum and urine of men and nonpregnant women without evidence of cancer. Concentrations of hCG and beta-hCG were measurable in 59-70% of serum samples and in 50-59% of urine samples. c beta-hCG was mostly undetectable in serum but measurable in 81% of urine samples. Concentrations were higher in women than in men, and hCG concentrations increased with age. Therefore, reference ranges based on the 97.5 percentile were calculated separately for women and men and for those < 50 and > 50 years. However, concentrations of hCG correlated much more strongly with those of follicle-stimulating hormone than with age. hCG concentrations in serum were similar to those reported before, but beta-hCG concentrations were below the detection limit of earlier assays, and the upper reference limit was one-fifth to one-tenth the cutoff concentrations used earlier. In urine, hCG and c beta-hCG were the major forms of hCG, and their concentrations were similar to those of hCG in serum.

scholarly journals Developmental Regulation of  VDJ Recombination By the Core Fragment of the T Cell Receptor α Enhancer

1997 ◽  
Vol 185 (1) ◽  
pp. 131-140 ◽  
Author(s):  
Joseph L. Roberts ◽  
Pilar Lauzurica ◽  
Michael S. Krangel
Keyword(s):  
T Cells ◽  
T Cell Receptor ◽  
Developmental Regulation ◽  
Cell Receptor ◽  
Vdj Recombination ◽  
The Core ◽  
Core Fragment ◽  
Ets Family ◽  
Αβ T Cells

The role of T cell receptor α enhancer (Eα) cis-acting elements in the developmental regulation of VDJ recombination at the TCR α/δ locus was examined in transgenic mice containing variants of a minilocus VDJ recombination substrate. We demonstrate that the 116-bp Tα1,2 core enhancer fragment of the 1.4-kb Eα is sufficient to activate the enhancer-dependent step of minilocus rearrangement, and that within Tα1,2, intact binding sites for TCF/LEF and Ets family transcription factors are essential. Although minilocus rearrangement under the control of the 1.4-kb Eα initiates at fetal day 16.5 and is strictly limited to αβ T cells, we find that rearrangement under the control of Tα1,2 initiates slightly earlier during ontogeny and occurs in both γδ and αβ T cells. We conclude that the core fragment of Eα can establish accessibility to the recombinase in developing thymocytes in vivo in a fashion that is dependent on the binding of TCF/LEF and Ets family transcription factors, but that these and other factors that bind to the Eα core cannot account for the precise developmental onset of accessibility that is provided by the intact Eα. Rather, our data suggests a critical role for factors that bind Eα outside of the core Tα1,2 region in establishing the precise developmental onset of TCR α rearrangement in vivo.

scholarly journals On Disallowing Punctual Intervals in Reflexive Semantics of Halpern-Shoham Logic

10.29007/fl6v ◽  
2018 ◽  
Author(s):  
Przemysław Andrzej Wałęga
Keyword(s):  
Computational Complexity ◽  
Expressive Power ◽  
Temporal Reasoning ◽  
Satisfiability Problem ◽  
Time Points ◽  
Modal Operators ◽  
The Core ◽  
Core Fragment ◽  
Horn Fragment

Halpern-Shoham logic (HS) is a very expressive and elegant formalism for interval temporal reasoning in which the satisfiability problem is undecidable. One of the methods to obtain HS-fragments of lower computational complexity is to adopt the softened (reflexive) seman- tics of the accessibility relations. In the paper we consider disallowing punctual intervals in reflexive semantics. We show that in this case we gain additional expressive power, which over discrete orders of time points results in PSpace-hardness of the Horn fragment of HS without diamond modal operators is and in undecidability of the core fragment of HS.

scholarly journals Dipeptidyl Peptidase-4 Is a Target Protein of Epigallocatechin-3-Gallate

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Huimin Hou ◽  
Ying Wang ◽  
Chunshi Li ◽  
Jian Wang ◽  
Yanli Cao
Keyword(s):  
Glucose Metabolism ◽  
Data Bank ◽  
Dipeptidyl Peptidase ◽  
Dynamics Simulation ◽  
Dipeptidyl Peptidase 4 ◽  
The Core ◽  
Core Fragment ◽  
Ic50 Value ◽  
The Stability

Epigallocatechin-3-gallate (EGCG), a major active ingredient in green tea, has various health benefits. It affects glucose metabolism, but the mechanism is not well understood. This study aimed to identify targets of EGCG related to glucose metabolism. The core fragment of EGCG is a flavonoid. The flavonoid scaffold was used as a substructure to find proteins cocrystallized with flavonoids in the Protein Data Bank. The proteins identified were screened in PubMed for known relationships with diabetes. Dipeptidyl peptidase-4 (DPP4; PDB 5J3J) was identified following this approach. By molecular docking, the interactions of EGCG and DPP4 were assessed. To test the stability of the interactions between EGCG and DPP4, molecular dynamics simulation for 100 ns was performed using Desmond software. In vitro, the concentration of EGCG required to inhibit DPP4 activity by 50% (the IC50 value) was 28.42 μM. These data provide a theoretical basis for intervention in glucose metabolism with EGCG.

Retracted Article: Tri-s-triazine (s-heptazine), a novel electron-deficient core for soft self-assembled supramolecular structures

2017 ◽  
Vol 53 (83) ◽  
pp. 11445-11448 ◽  
Author(s):  
Irla Siva Kumar ◽  
Sandeep Kumar
Keyword(s):  
Liquid Crystals ◽  
Supramolecular Structures ◽  
Discotic Liquid Crystals ◽  
The Core ◽  
Core Fragment ◽  
New Family ◽  
Retracted Article ◽  
Self Assembled

Tri-s-triazine (s-heptazine) is discovered as the core fragment for a new family of discotic liquid crystals.

A Radioimmunoassay for the Core Fragment of the Human Chorionic Gonadotropinβ-Subunit

1988 ◽  
Vol 66 (3) ◽  
pp. 538-545 ◽  
Author(s):  
ANTOINE H. AKAR ◽  
ROBERT E. WEHMANN ◽  
DIANA L. BLITHE ◽  
CATHERINE BLACKER ◽  
BRUCE C. NISULA
Keyword(s):  
The Core ◽  
Core Fragment

Ugi-4-Component Reaction Enabling Rapid Access to the Core Fragment of Massadine

2011 ◽  
Vol 13 (1) ◽  
pp. 78-81 ◽  
Author(s):  
Gary M. Chinigo ◽  
Alexander Breder ◽  
Erick M. Carreira
Keyword(s):  
The Core ◽  
Core Fragment ◽  
Rapid Access

What face familiarity feelings say about the lateralization of specific entities within the core system

2019 ◽  
Vol 42 ◽  
Author(s):  
Guido Gainotti
Keyword(s):  
Temporal Lobe ◽  
Memory System ◽  
Core System ◽  
The Core ◽  
Memory Traces ◽  
Specific Memory ◽  
Target Article ◽  
Temporal Structures ◽  
The Right

Abstract The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

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