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1.
Comput Intell Neurosci ; 2016: 9174683, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26904105

RESUMEN

The discordance between expressions interpretable by a natural language interface (NLI) system and those answerable by a knowledge base is a critical problem in the field of NLIs. In order to solve this discordance problem, this paper proposes a method to translate natural language questions into formal queries that can be generated from a graph-based knowledge base. The proposed method considers a subgraph of a knowledge base as a formal query. Thus, all formal queries corresponding to a concept or a predicate in the knowledge base can be generated prior to query time and all possible natural language expressions corresponding to each formal query can also be collected in advance. A natural language expression has a one-to-one mapping with a formal query. Hence, a natural language question is translated into a formal query by matching the question with the most appropriate natural language expression. If the confidence of this matching is not sufficiently high the proposed method rejects the question and does not answer it. Multipredicate queries are processed by regarding them as a set of collected expressions. The experimental results show that the proposed method thoroughly handles answerable questions from the knowledge base and rejects unanswerable ones effectively.


Asunto(s)
Almacenamiento y Recuperación de la Información , Bases del Conocimiento , Lenguaje , Procesamiento de Lenguaje Natural , Algoritmos , Ontologías Biológicas , Bases de Datos Factuales/estadística & datos numéricos , Geografía , Humanos , Semántica
2.
J Biol Inorg Chem ; 11(5): 663-9, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16724226

RESUMEN

The internalization of a series of water-soluble CdSe/CdS quantum dots (QDs) stabilized by citrate, isocitrate, succinate, and malate by Escherichia coli is established by epifluorescence and confocal fluorescence scanning microscopy, fluorimetry, and UV-vis spectroscopy on whole and lysed bacterial cells. The organic-acid-stabilized QDs span a range in size from 3.8+/-1.1 to 6.0+/-2.4 nm with emission wavelengths from 540 to 630 nm. QDs of different sizes (i.e., 3.8-6 nm) can enter the bacterium and be detected on different fluorescence channels with little interference from other QDs as a result of the distinct emission profiles (i.e., 540-630 nm, respectively). Costaining QD-labeled E. coli with 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) demonstrates that the QDs and DAPI are colocalized within E. coli, whereas costaining QD-labeled E. coli with membrane dye FM4-64 shows that the FM4-64 is localized in the outer bacterial membrane and that the QDs are inside.


Asunto(s)
Compuestos de Cadmio/metabolismo , Escherichia coli/citología , Puntos Cuánticos , Compuestos de Selenio/metabolismo , Coloración y Etiquetado/métodos , Sulfuros/metabolismo , Escherichia coli/metabolismo , Microscopía Confocal
3.
J Am Chem Soc ; 127(35): 12164-5, 2005 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16131161

RESUMEN

This work demonstrates a method for inducing site-specific nucleation and subsequent growth of large oriented organic semiconductor single crystals using micropatterned self-assembled monolayers (SAMs). We demonstrate growth of oriented, patterned, and large organic semiconductor single crystals for potential use in organic electronic devices. The control over multiple parameters in a single system has not yet been reported. The ability to control various aspects of crystal growth in one system provides a powerful technique for the bottom-up fabrication of organic single-crystal semiconductor devices.

5.
Chem Commun (Camb) ; (13): 1524-5, 2004 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-15216362

RESUMEN

Highly ordered mesoporous materials constructed with integrated polymer-silica hybrid frameworks can be obtained via a one-step synthetic strategy using a mixture of polymer and silicate as the framework sources in the presence of a structure-directing agent.

7.
J Am Chem Soc ; 125(14): 4032-3, 2003 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-12670208

RESUMEN

The combined effect of templating and solution additives on calcite crystallization was studied. Self-assembled monolayers of mercaptoundecanoic acid supported on silver, as templates, induced the uniform, oriented nucleation of calcite from the (012) plane. The presence of Mg2+ in the crystallizing solution affected the crystal growth dramatically, due to the selective Mg binding to the calcite planes roughly parallel to the c-axis. Highly homogeneous arrays of oriented crystals with characteristic sizes, shapes, and morphology, depending on the relative concentration of Mg and Ca ions, were synthesized.


Asunto(s)
Materiales Biomiméticos/química , Carbonato de Calcio/química , Ácidos Carboxílicos/química , Magnesio/química , Cristalización , Microscopía Electrónica de Rastreo
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