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1.
Lang Speech Hear Serv Sch ; 51(1): 128-143, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31684815

RESUMO

Purpose The purpose of this study was to provide reference data and evaluate the psychometric properties for the finite verb morphology composite (FVMC) measure in children between 4 and 9 years of age from the database of the Edmonton Narrative Norms Instrument (ENNI; Schneider, Dubé, & Hayward, 2005). Method Participants included 377 children between age 4 and age 9, including 300 children with typical language and 77 children with language impairment (LI). Narrative samples were collected using a story generation task. FVMC scores were computed from the samples. Split-half reliability, concurrent criterion validity, and diagnostic accuracy for FVMC were further evaluated. Results Children's performance on FVMC increased significantly between age 4 and age 9 in the typical language and LI groups. Moreover, the correlation coefficients for the split-half reliability and concurrent criterion validity of FVMC were medium to large (rs ≥ .429, ps < .001) at each age level. The diagnostic accuracy of FVMC was good or acceptable from age 4 to age 7, but it dropped to a poor level at age 8 and age 9. Conclusion With the empirical evidence, FVMC is appropriate for identifying children with LI between age 4 and age 7. The reference data of FVMC could also be used for monitoring treatment progress. Supplemental Material https://doi.org/10.23641/asha.10073183.

2.
Am J Speech Lang Pathol ; 28(4): 1448-1462, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31433664

RESUMO

Purpose The purpose of this article was to provide the reference data and evaluate psychometric properties for the percent grammatical utterances (PGU; Eisenberg & Guo, 2013) in children between 4 and 9 years of age from the database of the Edmonton Narrative Norms Instrument (ENNI; Schneider, Dubé, & Hayward, 2005). Method Participants were 377 children who were between 4 and 9 years of age, including 300 children with typical language (TL) and 77 children with language impairment (LI). Narrative samples were collected using the ENNI protocol (i.e., a story generation task). PGU was computed from the samples. Split-half reliability, concurrent criterion validity, and diagnostic accuracy for PGU were further evaluated. Results PGU increased significantly in children between 4 and 9 years of age in both the TL and LI groups. In addition, the correlation coefficients for the split-half reliability and concurrent criterion validity of PGU were all large (rs ≥ .557, ps < .001). The diagnostic accuracy of PGU was also good or acceptable from ages 4 to 9 years. Conclusions With the attested psychometric properties, PGU computed from the ENNI could be used as an assessment tool for identifying children with LI between 4 and 9 years of age. The reference data of PGU could also be used for monitoring treatment progress. Supplemental Material https://doi.org/10.23641/asha.9630590.

3.
Materials (Basel) ; 11(6)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848981

RESUMO

In this study, a previously known high-affinity silica binding protein (SB) was genetically engineered to fuse with an integrin-binding peptide (RGD) to create a recombinant protein (SB-RGD). SB-RGD was successfully expressed in Escherichia coli and purified using silica beads through a simple and fast centrifugation method. A further functionality assay showed that SB-RGD bound to the silica surface with an extremely high affinity that required 2 M MgCl2 for elution. Through a single-step incubation, the purified SB-RGD proteins were noncovalently coated onto an electrospun silica nanofiber (SNF) substrate to fabricate the SNF-SB-RGD substrate. SNF-SB-RGD was characterized by a combination of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and immunostaining fluorescence microscopy. As PC12 cells were seeded onto the SNF-SB-RGD surface, significantly higher cell viability and longer neurite extensions were observed when compared to those on the control surfaces. These results indicated that SB-RGD could serve as a noncovalent coating biologic to support and promote neuron growth and differentiation on silica-based substrates for neuronal tissue engineering. It also provides proof of concept for the possibility to genetically engineer protein-based signaling molecules to noncovalently modify silica-based substrates as bioinspired material.

4.
Lang Speech Hear Serv Sch ; 49(3): 622-627, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29710199

RESUMO

Purpose: In this letter, the authors respond to Pavelko and Owens' (2017) newly advanced set of procedures for language sample analysis: Sampling Utterances and Grammatical Analysis Revised (SUGAR). Method: The authors contrast some of the new guidelines for transcription, morpheme segmentation, and language sample elicitation in SUGAR with traditional conventions for language sample analysis (LSA). They address the potential impact of the new guidelines on some of the target measures in SUGAR-mean length of utterances in morphemes (MLUm), words per sentence (WPS), and clauses per sentence (CPS)-and provide their suggestions. Results: Inclusion of partially intelligible utterances in SUGAR may over- or underestimate children's MLUm and reduce the reliability of computing WPS. Counting derivational morphemes and the component morphemes of catenatives (e.g., gonna) may result in overestimation of children's morphosyntactic skills. Conclusion: Further data are needed to determine whether MLUm including derivational morphemes and the component morphemes of catenatives is a better measure of children's morphosyntactic skills than MLUm excluding those morphemes. Pending such data, the authors recommend maintaining traditional LSA conventions and measures. Furthermore, free, fast automated utilities already exist that reduce barriers for clinicians to conduct informative, in-depth LSA.


Assuntos
Linguagem Infantil , Idioma , Criança , Humanos , Reprodutibilidade dos Testes , Açúcares
5.
Nanomaterials (Basel) ; 8(3)2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29538349

RESUMO

In this study, we first synthesized a slow-degrading silica nanofiber (SNF2) through an electrospun solution with an optimized tetraethyl orthosilicate (TEOS) to polyvinyl pyrrolidone (PVP) ratio. Then, laminin-modified SNF2, namely SNF2-AP-S-L, was obtained through a series of chemical reactions to attach the extracellular matrix protein, laminin, to its surface. The SNF2-AP-S-L substrate was characterized by a combination of scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy, nitrogen adsorption/desorption isotherms, and contact angle measurements. The results of further functional assays show that this substrate is a biocompatible, bioactive and biodegradable scaffold with good structural integrity that persisted beyond 18 days. Moreover, a synergistic effect of sustained structure support and prolonged biochemical stimulation for cell differentiation on SNF2-AP-S-L was found when neuron-like PC12 cells were seeded onto its surface. Specifically, neurite extensions on the covalently modified SNF2-AP-S-L were significantly longer than those observed on unmodified SNF and SNF subjected to physical adsorption of laminin. Together, these results indicate that the SNF2-AP-S-L substrate prepared in this study is a promising 3D biocompatible substrate capable of sustaining longer neuronal growth for tissue-engineering applications.

6.
Am J Speech Lang Pathol ; 27(2): 633-646, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29392298

RESUMO

Purpose: This study investigated whether language samples elicited during play and description of pictured events would yield the same results for developmental sentence scoring (DSS). Method: Two language samples were elicited from 58 three-year-olds. One sample was elicited during play with a parent, and the other sample was elicited by an examiner asking children to talk about pictured events in response to elicitation questions. Results: DSS scores were not significantly different between the play and event description samples. However, sentence points were significantly higher for the play sample than for the event description sample. Although there was a correlation between sample types for both DSS and sentence points, the correlation for DSS (r = .52) was below an acceptable level, and the correlation for sentence points (r = .71) was at a minimally acceptable level. Agreement between sample types for pass-fail decisions on the DSS scores using the 10th percentile cutoff recommended by Lee (1974) was only moderate (78%). Conclusion: The current study shows that type of language samples could affect DSS and sentence point scores of 3-year-olds and, hence, the passing and failing decisions for their performance on DSS.


Assuntos
Comportamento Infantil , Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Testes de Linguagem , Narração , Estimulação Luminosa , Jogos e Brinquedos/psicologia , Fatores Etários , Pré-Escolar , Feminino , Humanos , Transtornos do Desenvolvimento da Linguagem/psicologia , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Gravação em Vídeo , Percepção Visual
7.
Lang Speech Hear Serv Sch ; 49(1): 98-107, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29209729

RESUMO

Purpose: This report investigated the validity of using percent grammatical responses (PGR) as a measure for assessing grammaticality. To establish construct validity, we computed the correlation of PGR with another measure of grammar skills and with an unrelated skill area. To establish concurrent validity for PGR, we computed the correlation of PGR with a previously validated measure of grammaticality, percent grammatical utterances (PGU), and examined the extent to which PGR and PGU agreed upon pass/fail decisions for children. Method: Participants included 79 3-year-olds from mostly middle socioeconomic status homes. Language samples were elicited by asking children to describe 15 pictures in response to 4 questions per picture. To calculate PGU, children's responses to all 4 questions were segmented into communication units, and each communication unit was evaluated for grammatical errors. To calculate PGR, the entire response to just the first question was evaluated for grammatical errors. Results: PGR scores significantly correlated with a standardized test of grammar (r = .70), but not with a measure of vocabulary (i.e., type-token ratio; r = .11). In addition, PGR scores were significantly correlated with PGU scores (r = .88). Agreement between PGR and PGU was 92% for pass decisions and 94% for fail decisions. Conclusions: The current study establishes the construct validity of PGR as a measure of grammar and supports the use of PGR as a measure to assess grammaticality.


Assuntos
Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Desenvolvimento da Linguagem , Testes de Linguagem/normas , Pré-Escolar , Comunicação , Feminino , Humanos , Linguística , Masculino , Reprodutibilidade dos Testes , Vocabulário
8.
J Am Chem Soc ; 139(40): 14033-14036, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28925691

RESUMO

Postsynthetic decoration of the Mn7, {MnIII⊂MnII6}, core with CdII in the outer shell to form the next generation Mn13Cd6, {MnIII⊂MnIII3MnII3⊂ MnII6CdII6}, core-shell disc was achieved and confirmed by single-crystal X-ray diffraction. The formation of Mn13Cd6 has only been successful with CdII and if the Cd salt is added within the first half hour window when the inner Mn7 has formed. EDX and ICP-AES gave the accurate content and confirm the average found by X-ray diffraction. HR-ESI-MS was even more precise by revealing three prominent molecular species, Mn13Cd6, Mn14Cd5 and Mn15Cd4, having a distribution of metals. The presence of nonmagnetic metal on the periphery reduces the exchange between these clusters as well as the low magnetic moment decreases the dipolar interaction resulting in a paramagnet compared to the ferrimagnetism found for the parent Mn19, {MnIII⊂MnIII3MnII3⊂MnII12}, disc. This study opens the way for the syntheses of heterometallic core-shell clusters in a controllable fashion.

9.
Chem Commun (Camb) ; 53(45): 6081-6084, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28503688

RESUMO

A new divergent intermolecular cascade annulation reaction of N-(arylsulfonyl)acrylamides with dual alkyl C(sp3)-H bonds for producing two types of five-membered rings, indanes and pyrrolidin-2-ones, is described. By using cycloalkanes and common alkanes as a one-carbon unit, an intermolecular [4+1] cascade carboannulation of N-(arylsulfonyl)acrylamides was achieved via a sequence of three C-H bond functionalization/aryl migration/desulfonylation that enables the formation of three C-C bonds and one N-H bond. When the one-carbon unit was changed to cycloalkyl ethers, the alternative intermolecular [4+1] cascade heteroannulation reaction occurred and allowed the construction of two C-C bonds and one C-N bond through dual C-H bond functionalization, aryl migration and desulfonylation cascades.

10.
ACS Appl Mater Interfaces ; 9(23): 19980-19987, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28537067

RESUMO

A family of six triple-decker complexes, {(MX)2[(pz)4]3} (Hpz = 4-nitropyrazole, MX = NaCl, 1; NaBr, 2; NaI, 3; KCl, 4; KBr, 5, and KI, 6), exhibiting inclusion of halides into inverse 12-metallacrown-4 [inv-(12-MCCu(I),pz-4)] array has been realized. Single-crystal X-ray crystallography of each compound reveals a common structural feature consisting of four CuI ions bonded by four pz to form a square metallomacrocycle comprising four metal centers and eight N atoms, thus giving an inv-[12-MCCu(I),pz-4] motif. Two halides are sandwiched by three inv-[12-MCCu(I),pz-4] to form triple-deckers that are further extended in an offset stacking mode by ligand-unsupported cuprophilicity interactions to form a one-dimensional chain structure. Halides are attached to six CuI centers with weak CuI···halogen interaction, resembling anion templates. High-resolution electrospray ionization mass spectrometry reveals that the predominant fragments corresponding to a half of the triple-decker structures of 1-3 exist in solution. Compounds 4, 5, and 6 showed excellent electrocatalytic activities toward the reduction of nitrite and can also be used as selective "turn-off" sensors for Ag(I) in water. The present results will be helpful for the future design and synthesis of functional inverse metallacrowns and their multiple-decker complexes.

11.
J Speech Lang Hear Res ; 60(4): 1062-1075, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28384729

RESUMO

Purpose: We sought to evaluate the development of grammatical accuracy in English-speaking children with cochlear implants (CIs) over a 3-year span. Method: Ten children who received CIs before age 30 months participated in this study at 3, 4, and 5 years postimplantation. For the purpose of comparison, 10 children each at ages 3, 4, and 5 years with typical hearing were included as well. All children participated in a story-retell task. We computed percent grammatical communication units (PGCU) in the task. Results: Children with CIs showed significant improvement in PGCU over the 3-year span. However, they produced lower PGCU than children with typical hearing who had matched hearing age at 4 and 5 years postimplantation. At the individual level, some children with CIs were able to produce PGCU comparable to children with typical hearing as early as 3 years after implantation. Better speech-perception skills at earlier time points were associated with higher PGCU at later time points. Moreover, children with and without CIs showed similar rankings in the types of grammatical errors. Conclusion: Despite having auditory-perceptual and information-processing constraints, children who received CIs before age 30 months were able to produce grammatical sentences, albeit with a delayed pattern.


Assuntos
Linguagem Infantil , Implantes Cocleares , Surdez/psicologia , Surdez/reabilitação , Linguística , Pré-Escolar , Surdez/cirurgia , Feminino , Humanos , Testes de Linguagem , Estudos Longitudinais , Masculino , Narração , Reprodutibilidade dos Testes , Percepção da Fala , Fatores de Tempo
12.
Inorg Chem ; 56(5): 2481-2489, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28199094

RESUMO

Two novel POM-based inorganic-organic hybrids, [Cu6II(2,2'-bipy)6(Mo6O22)(SiW12O40)]n (1), and {[Cu6II(ppz)6(H2O)5(MoO4)(SiW12O40)]·4H2O}n (2) (2,2'-bipy = 2,2'-bipyridine, Hppz = 3-(pyrid-2-yl)pyrazole), have been constructed from heteropolytungstates and molybdates. Two compounds have been identified by single crystal X-ray diffraction, elemental analysis, and FT-IR. Compound 1 shows a 1D (one-dimensional) chain structure constructed from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu6(2,2'-bipy)6] modified isopolymolybdates [Mo6O22]8-. Compound 2 also represents a 1D chain-like motif built from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu8(ppz)6(H2O)5] modified molybdates MoO42-. Compound 1 represents the first example of POM-based inorganic-organic hybrid with mixed heteropolytungstates and isopolymolybdates. ESI-MS (electrospray ionization mass spectrometry) technique was employed to reveal the species and their evolutions in the hydrothermal reaction, whereby trivacant [SiW9] building block gradually transforms to classical Keggin [SiW12] during assembly process. Furthermore, the electrocatalytic and magnetic properties were discussed in details.

13.
Inorg Chem ; 56(3): 1591-1598, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28117988

RESUMO

Inspired by the transition-metal-oxo cubical Mn4CaO5 in photosystem II, we herein report a disc-like heptanuclear mixed-valent cobalt cluster, [CoII5CoIII2(mdea)4(N3)2(CH3CN)6(OH)2(H2O)2·4ClO4] (1, H2mdea = N-methyldiethanolamine), for photocatalytic oxygen evolution. The topology of the Co7 core resembles a small piece of cobaltate protected by terminal H2O, N3-, CH3CN, and multidentate N-methyldiethanolamine at the periphery. Under the optimal photocatalytic conditions, 1 exhibits water oxidation activity with a turnover number (TON) of 210 and a turnover frequency (TOFinitial) of 0.23 s-1. Importantly, electrospray mass spectrometry (ESI-MS) was used to not only identify the possible main active species in the water oxidation reaction but also monitor the evolutions of oxidation states of cobalt during the photocatalytic reactions. These results shed light on the design concept of new water oxidation catalysts and mechanism-related issues such as the key active intermediate and oxidation state evolution in the oxygen evolution process. The magnetic properties of 1 were also discussed in detail.

14.
Inorg Chem ; 55(17): 9006-11, 2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27548500

RESUMO

A planar hexanuclear cobalt ring was clamped by two bivacant α1-[PW10O37](9-) with the assistance of the pyridazine bridges to form a novel sandwiched Co(II)-polyoxometalate cluster compound, [Na(H2O)6][Co3(OH) (pydz)4(H2O)7][Co6(PW10O37)2(pydz)4(H2O)6]·43H2O (1; pydz = pyridazine).This cluster was identified by X-ray single-crystal diffraction, elemental analysis, Fourier transform IR and UV-visible spectroscopies, and cyclic voltammetry (CV). Structural analysis reveals that 1 comprises a hexahydrated sodium, a trinuclear [Co3(OH) (pydz)4(H2O)7](5+) cationic cluster, and an anionic [Co6(PW10O37)2(pydz)4(H2O)6](6-) sandwiched cluster, thus giving an intrinsical intercluster compound. The isolation of such cluster was dependent on the in situ transformation of trivacant [α-P2W15O56](12-) to α1-[PW10O37](9-) under the hydrothermal condition. The CV shows reversible multielectron waves from the redox of W(VI) in 1. Cluster 1 exhibits remarkable electrocatalytic activity toward the reduction of nitrite. Magnetism studies indicated a weak anti-ferromagnetic exchange interaction between Co(II) ions within 1.

15.
J Speech Lang Hear Res ; 59(2): 317-29, 2016 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27088899

RESUMO

PURPOSE: To determine the diagnostic accuracy of the finite verb morphology composite (FVMC), number of errors per C-unit (Errors/CU), and percent grammatical C-units (PGCUs) in differentiating school-aged children with language impairment (LI) and those with typical language development (TL). METHOD: Participants were 61 six-year-olds (50 TL, 11 LI) and 67 eight-year-olds (50 TL, 17 LI). Narrative samples were collected using a story-generation format. FVMC, Errors/CU, and PGCUs were computed from the samples. RESULTS: All of the three measures showed acceptable to good diagnostic accuracy at age 6, but only PGCUs showed acceptable diagnostic accuracy at age 8 when sensitivity, specificity, and likelihood ratios were considered. CONCLUSION: FVMC, Errors/CU, and PGCUs can all be used in combination with other tools to identify school-aged children with LI. However, FVMC and Errors/CU may be an appropriate diagnostic tool up to age 6. PGCUs, in contrast, may be a sensitive tool for identifying children with LI at least up to age 8 years.


Assuntos
Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Testes de Linguagem , Narração , Fatores Etários , Criança , Feminino , Humanos , Funções Verossimilhança , Linguística , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Dalton Trans ; 45(20): 8404-11, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27108482

RESUMO

Modified classical trivacant Wells-Dawson α-[P2W15O56](12-) and the assembly of related sandwiched transition metal clusters are of interest, but surprisingly few reports of these materials exist because of the sensitivity of α-[P2W15O56](12-) to the assembly environment. Herein, we describe the pH-controlled assembly of two novel Dawson-sandwiched clusters, (H2bpz)6[Co2(P2W16O57)2]·22H2O (1, bpz = 3,3',5,5'-tetramethyl-4,4'-bipyrazole) and (H2bpz)6[Co3H2(P2W16O57)(P2W15O56)(H2O)]·12H2O (2), involving the in situ transformation of α-[P2W15O56](12-). Both clusters were characterized by X-ray single-crystal diffraction, FT-IR spectroscopy, UV-Visible spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and elemental analyses. X-ray crystallography showed that both heteropolytungstates become divacant α-[P2W16O57](8-) and symmetrically encapsulate two edge-shared CoO6 octahedra in the interior in 1, while only one divacant α-[P2W16O57](8-) is observed in 2, which combined with another trivacant α-[P2W15O56](12-) to asymmetrically clamp three edge-shared CoO6 octahedra. The α-[P2W16O57](8-) heteropolytungstate should be generated in situ from α-[P2W15O56](12-)via self-decomposition equilibria in solution. Their electrochemical behaviors reveal characteristic multi-electron redox processes related to W(VI) centers. The electrocatalytic reduction performances toward nitrite, hydrogen peroxide, chlorate, bromate and iodate were fully measured and discussed; among these species, both clusters exhibit the best electrocatalytic activity towards the reduction of bromate. Magnetic measurements indicate weak ferromagnetic exchange interactions between Co atoms sandwiched by vacant polyoxometalates.

17.
Semin Speech Lang ; 37(2): 106-16, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27111270

RESUMO

This article reviews the existing literature on the diagnostic accuracy of two grammatical accuracy measures for differentiating children with and without language impairment (LI) at preschool and early school age based on language samples. The first measure, the finite verb morphology composite (FVMC), is a narrow grammatical measure that computes children's overall accuracy of four verb tense morphemes. The second measure, percent grammatical utterances (PGU), is a broader grammatical measure that computes children's accuracy in producing grammatical utterances. The extant studies show that FVMC demonstrates acceptable (i.e., 80 to 89% accurate) to good (i.e., 90% accurate or higher) diagnostic accuracy for children between 4;0 (years;months) and 6;11 in conversational or narrative samples. In contrast, PGU yields acceptable to good diagnostic accuracy for children between 3;0 and 8;11 regardless of sample types. Given the diagnostic accuracy shown in the literature, we suggest that FVMC and PGU can be used as one piece of evidence for identifying children with LI in assessment when appropriate. However, FVMC or PGU should not be used as therapy goals directly. Instead, when children are low in FVMC or PGU, we suggest that follow-up analyses should be conducted to determine the verb tense morphemes or grammatical structures that children have difficulty with.


Assuntos
Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Linguística , Criança , Humanos , Idioma , Testes de Linguagem , Narração
18.
Chemistry ; 21(51): 18847-54, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26541877

RESUMO

The encapsulation of carbonate derived from atmospheric CO2 has resulted in an icosanuclear heteropolyoxocopperate, isolated as a metal-organic 1D chain, 2D sheet, or 3D framework, in which the Cu20 nanocluster represents the first eight-capped α-Keggin polyoxometalate with the late-transition-metal Cu(II) as the polyatom, CO3(2-) as the heteroanion, and OH(-) and suc(2-) or glu(2-) (H2suc=succinic acid; H2glu=glutaric acid) as the terminal ligands, which suggests a conceptual similarity to classical polyoxometalates. Even in the presence of competitive SO4(2-) in the assembly system, the CO3(2-) anion is still captured as a template to direct the formation of the Cu20 nanocluster, which indicates the stronger templation ability of CO3(2-) compared with SO4(2-). When other aliphatic dicarboxylates, such as glutaric acid, were used as ligands, the CO3(2-)-templated Cu20 nanocluster was maintained and acted as a cluster building unit (CBU) to be linked by two glutarate bridges to generate a distinct 1D metal-organic chain. This report presents not only a rare example of a huge anion-templated transition-metal cluster, but also its use as a robust CBU to construct novel coordination architectures. Variable-temperature magnetic susceptibility studies revealed that an antiferromagnetic interaction exists within the Cu20 nanocluster. The correlation between the coordination structure and the electron paramagnetic resonance spectra recorded of both powder and single-crystal samples are discussed in detail.

19.
J Speech Lang Hear Res ; 58(3): 987-1000, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25677929

RESUMO

PURPOSE: The purpose of this study was to determine whether children with cochlear implants (CIs) are sensitive to statistical characteristics of words in the ambient spoken language, whether that sensitivity changes in expected ways as their spoken lexicon grows, and whether that sensitivity varies with unilateral or bilateral implantation. METHOD: We analyzed archival data collected from the parents of 36 children who received cochlear implantation (20 unilateral, 16 bilateral) before 24 months of age. The parents reported their children's word productions 12 months after implantation using the MacArthur Communicative Development Inventories: Words and Sentences (Fenson et al., 1993). We computed the number of words, out of 292 possible monosyllabic nouns, verbs, and adjectives, that each child was reported to say and calculated the average phonotactic probability, neighborhood density, and word frequency of the reported words. RESULTS: Spoken vocabulary size positively correlated with average phonotactic probability and negatively correlated with average neighborhood density, but only in children with bilateral CIs. CONCLUSION: At 12 months postimplantation, children with bilateral CIs demonstrate sensitivity to statistical characteristics of words in the ambient spoken language akin to that reported for children with normal hearing during the early stages of lexical development. Children with unilateral CIs do not.


Assuntos
Linguagem Infantil , Implantes Cocleares , Surdez/reabilitação , Linguística , Percepção da Fala , Pré-Escolar , Surdez/cirurgia , Feminino , Humanos , Lactente , Testes de Linguagem , Masculino , Estatística como Assunto
20.
Lang Speech Hear Serv Sch ; 46(2): 141-53, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25615272

RESUMO

PURPOSE: The goal of this study was to investigate the extent to which sample length affected the reliability of total number of words (TNW), number of different words (NDW), and mean length of C-units in morphemes (MLCUm) in parent-elicited conversational samples for 3-year-olds. METHOD: Participants were sixty 3-year-olds. A 22-min language sample was collected from each child during free play with the parent in the laboratory. Samples of 1, 3, 7, and 10 min were extracted from the 22-min samples. TNW, NDW, and MLCUm were computed from each shorter sample and the 22-min sample. TNW and NDW were adjusted by number of minutes for comparisons. The differences and correlations between each shorter sample cut and the 22-min sample on MLCUm and adjusted TNW and NDW were computed. RESULTS: The shorter samples and the 22-min samples significantly differed in adjusted TNW and NDW, but not in MLCUm. TNW reached an acceptable reliability level (i.e., r = .90) in 7-min samples. NDW and MLCUm approached the acceptable reliability level (rs = .88) in 7-min samples and reached it in 10-min samples. CONCLUSION: For conversational language samples with similar collection procedures, samples of 7 to 10 min are desirable for calculating TNW, NDW, and MLCUm in 3-year-olds.


Assuntos
Linguagem Infantil , Testes de Linguagem , Pré-Escolar , Feminino , Humanos , Masculino , Pais , Jogos e Brinquedos , Reprodutibilidade dos Testes , Fatores de Tempo
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