Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 77
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Econ Entomol ; 102(6): 2224-32, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20069852

RESUMEN

The purpose of this study was to develop and evaluate lures for adult green June beetles, Cotinis nitida (L.) (Coleoptera: Scarabaeidae), for future use in a mass trapping program. Volatile organic compounds collected from headspace of green June beetles feeding on fermenting ripe apple (Malus spp.), the natural lure that elicits feeding aggregations, were identified and confirmed by gas chromatography and mass spectrometry. Yellow funnel traps baited with 91% isopropanol or the five component blend were equally effective in eliciting aggregation behavior and often more attractive to green June beetles than the natural lure. In 2008, three trap lines adjacent and parallel to the perimeter of two vineyards, each with 12 Xpando yellow funnel traps baited with either 91% isopropanol or the five component blend, differed in catch of green June beetles across sample dates, and sample date by bait interaction but there were no differences among these two baits. A season total of 324,007 green June beetle were captured by these 36 baited traps. A brief review is included of fermentation volatiles attractive to insects. We conclude with the potential cost to use mass trapping against adult green June beetles.


Asunto(s)
Escarabajos/química , Conducta Alimentaria , Control de Insectos , Feromonas/aislamiento & purificación , Compuestos Orgánicos Volátiles/aislamiento & purificación , Animales , Femenino , Fermentación , Frutas , Masculino , Malus
2.
Vet Comp Orthop Traumatol ; 21(2): 119-24, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18545713

RESUMEN

In the human and veterinary orthopaedic literature it has been implied that intercondylar notch stenosis is a mechanical factor in cranial cruciate ligament rupture and intraarticular graft failure. The patients in this study were classified as normal (32), unilateral cruciate rupture (23), or bilateral cruciate rupture (17). The dogs were placed under general anaesthesia and both stifles were scanned via computed tomography (CT) as previously described. Three CT slices at predetermined levels were evaluated within the notch. Measurements included opening notch angle, notch width and height, condyle width, and notch width index (notch width/condyle width) at two different heights within the notch. Intercondylar notch measurements at the most cranial extent were significantly more narrow in unilateral and bilaterally affected stifles when compared to the normal population. Significant differences were noted in the opening notch angle (ONA), notch width index (NWI), NWI at two thirds notch height (NWI2/3), and tibial slope index (TSI). No significant differences were noted between unilateral and bilateral affected stifles. Increased mechanical contact of the cranial cruciate ligament with a stenotic intercondylar notch may predispose the ligament to mechanical wear and structural weakening. Intercondylar notch measurements have been used as a tool to predict the risk of anterior cruciate ligament injury in young human athletes, and to assess the risk factors for intra-articular graft replacements. Our findings may be useful in developing similar predictive models using stifle CT scans.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/diagnóstico por imagen , Ligamentos Articulares/diagnóstico por imagen , Rodilla de Cuadrúpedos/diagnóstico por imagen , Tomografía Computarizada por Rayos X/veterinaria , Animales , Perros , Femenino , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/veterinaria , Ligamentos Articulares/lesiones , Masculino , Interpretación de Imagen Radiográfica Asistida por Computador , Rotura/veterinaria , Rodilla de Cuadrúpedos/anatomía & histología , Rodilla de Cuadrúpedos/lesiones , Tomografía Computarizada por Rayos X/métodos
3.
J Econ Entomol ; 109(4): 1799-806, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27346633

RESUMEN

The rednecked cane borer, Agrilus ruficollis (F.), is a pest of cultivated and wild blackberries in the midwestern and eastern parts of the United States. Damage from this pest occurs from larvae girdling primocanes and tunneling in the pith, forming galls that can potentially reduce yields. There is only one registered insecticide and no trap available for monitoring. Paints mimicking the spectral reflectance of blackberry leaves and canes of both primocane and floricane were applied to wooden dowels or corrugated plastic mimicking the shape of blackberry canes and leaves. The dowels or corrugated plastic were covered with sticky Tangletrap, and field was evaluated for attractiveness to A. ruficollis for three years, with modifications to trap design each year. Commercially available emerald ash borer, Agrilus planipennis Fairmaire, funnel traps were evaluated for attractiveness to A. ruficollis in 2014. In 2011, the greatest numbers of A. ruficollis adults were captured on prism-shaped, primocane-mimicking traps that reflected light at a peak wavelength between 540-560 nm. In 2012 and 2013, field tests demonstrated that more A. ruficollis adults were captured on green emerald ash borer traps. Testing in 2014 reinforced the previous findings that A. ruficollis was most attracted to the green emerald ash borer traps. In 2013, it was noted that colored traps usually captured significantly more A. ruficollis males than females. This indicated a need to determine if there was a chemical cue used by A. ruficollis adult females to locate and oviposit on only blackberry primocanes and not floricanes.


Asunto(s)
Escarabajos/fisiología , Color , Control de Insectos/métodos , Fototaxis , Animales , Femenino , Masculino , Estaciones del Año
4.
Oncogene ; 5(11): 1731-3, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2267138

RESUMEN

The retinoblastoma (Rb) gene is a recessive oncogene or tumor-suppressor gene whose inactivation leads to the development of tumors. Recently, evidence pointing to a role for the Rb gene in the differentiation of certain human cell types has been presented. We have studied three mouse cell lineages to determine whether there is a correlation between Rb gene expression and differentiation. We find that induction of mouse erythroleukemia cell differentiation with either dimethylsulfoxide (DMSO) or hexamethylene bisacetamide (HMBA) leads to increased expression of Rb mRNA. Increased expression of Rb mRNA was also found in S2 myoblasts induced by mitogen depletion to become differentiated myotubes. In the B-cell lineage, Rb expression is low in pre-B and B cell lines but high in plasmacytomas, which represent late stages of B cell differentiation. Thus, in all three lineages (erythroid, muscle, and B-cell) late stages of differentiation are associated with increased amounts of Rb mRNA.


Asunto(s)
Expresión Génica , Genes de Retinoblastoma/genética , Acetamidas/farmacología , Animales , Linfocitos B/metabolismo , Linfocitos B/patología , Diferenciación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Embrión de Mamíferos , Cinética , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/patología , Ratones , Músculos/citología , Músculos/metabolismo , Fosforilación , Plasmacitoma/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Células Tumorales Cultivadas
5.
J Mol Biol ; 166(2): 203-10, 1983 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-6854643

RESUMEN

We have used vesicles made from delipidated bacteriorhodopsin and synthetic lecithins to address the following questions. If the transmembrane dimension of a protein hydrophobic surface differs from the equilibrium thickness of its lipid bilayer environment, will protein monomers aggregate to decrease the protein-lipid contact surface area? If so, how large must the difference be to induce aggregation? Using lecithins with acyl chains from di-10:0 to di-24:1, the thickness of the bilayer hydrocarbon region above the lipid phase transition temperature (tm) was varied from 14.5 A less than to 7.5 A more than the transmembrane dimension of the bacteriorhodopsin hydrophobic region. Bacteriorhodopsin remains dispersed when the surrounding bilayer hydrophobic region is 4 A thicker or 10 A thinner than the bacteriorhodopsin hydrophobic surface. Only the thin- (10:0) and thick- (24:1) bilayer samples showed any bacteriorhodopsin aggregation above tm. Thus a surprisingly large difference between protein and lipid hydrophobic thicknesses can be accommodated without protein aggregation. The lipid bilayer can evidently sustain large local distortions with a small change in free energy.


Asunto(s)
Bacteriorodopsinas , Carotenoides , Membrana Dobles de Lípidos , Técnica de Fractura por Congelación , Halobacterium , Fosfatidilcolinas , Temperatura
6.
J Mol Biol ; 166(2): 211-7, 1983 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-6854644

RESUMEN

The thickness of the lipid bilayer in vesicles made of pure phosphatidylcholines, with acyl chain lengths ranging from 10 to 24 carbons, has been determined by analysis of continuous X-ray scattering data from vesicle pellets at temperatures above the lipid phase transition temperature. Bilayer thickness was found to vary linearly with the number of carbons per acyl chain. The lines for saturated and monounsaturated acyl chains were slightly displaced but had similar slopes. For the saturated species di-12:0, di-14:0, di-16:0, and di-18:0 phosphatidylcholine the surface areas per molecule were all 65.7 to 66.5 A2, while the monounsaturated species and di-10:0 phosphatidylcholine all occupied 67.7 to 70.1 A2 per molecule.


Asunto(s)
Membrana Dobles de Lípidos , Fosfatidilcolinas , Temperatura , Difracción de Rayos X
7.
J Mol Biol ; 222(2): 281-300, 1991 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-1960728

RESUMEN

The water-accessible volumes, the amounts of all significant osmolytes, and the protein concentration in the cytoplasm of aerobically grown Escherichia coli K-12 have been determined as a function of the osmolarity of the minimal growth medium. The volume of cytoplasmic water (Vcyto) decreases linearly with increasing osmolarity from 2.23(+/- 0.12) microliters/mg dry weight in cells grown at 0.10 OSM to 1.18(+/- 0.06) microliters/mg dry weight at 1.02 OSM. Above 0.28 OSM, growth rate decreases linearly with increasing osmolarity. The growth rate extrapolates to zero at an osmolarity of approximately 1.8, corresponding to an estimated Vcyto of 0.5(+/- 0.2) microliters/mg dry weight. Measurements of Vcyto in titrations of non-growing cells with the plasmolyzing agent NaCl were used to obtain volumes of "bound" water (presumably water of macromolecular hydration) and cytoplasmic osmotic coefficients for cells grown in medium of low (0.10 OSM) and moderate (0.28 OSM) osmolarity. The volume of bound water Vb is similar in the two osmotic conditions (Vb = 0.40(+/- 0.04) microliters/mg dry wt), and corresponds to approximately 0.5 g H2O/g cytoplasmic macromolecule. Since Vcyto decreases with increasing osmolarity, whereas Vb appears to be independent of osmolarity, water of hydration becomes a larger fraction of Vcyto as the osmolarity of the growth medium increases. Growth appears to cease at the osmolarity where Vcyto is approximately equal to Vb. K+ and glutamate (Glu-) are the only significant cytoplasmic osmolytes in cells grown in medium of low osmolarity. The amount of K+ greatly exceeds that of Glu-. Analysis of cytoplasmic electroneutrality indicates that the cytoplasm behaves like a concentrated solution of the K+ salt of cytoplasmic polyanions, in which the amount of additional electrolyte (K+ Glu-) increases with increasing osmolarity. As the osmolarity of the growth medium becomes very low, the cytoplasm approaches an electrolyte-free K+-polyanion solution. In vivo osmotic coefficients were determined from the variation of Vcyto with external osmolarity in plasmolysis titrations of non-growing cells. The values obtained (phi = 0.54(+/- 0.06) for cells grown at 0.10 OSM and phi = 0.71(+/- 0.11) at 0.28 OSM) indicate a high degree of non-ideality of intracellular ions arising from coulombic interactions between K+ and cytoplasmic polyanions. Analysis of these osmotic coefficients using polyelectrolyte theory indicates that the thermodynamic activity of cytoplasmic K+ increases from approximately 0.14 M in cells grown at an external osmolarity of 0.10 OSM to approximately 0.76 M at 1.02 OSM.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Escherichia coli/fisiología , Equilibrio Hidroelectrolítico , Fenómenos Biofísicos , Biofisica , División Celular , Medios de Cultivo , Citoplasma/fisiología , ADN Bacteriano/metabolismo , Proteínas de Unión al ADN/metabolismo , Iones , Termodinámica , Agua/metabolismo
8.
Genes Brain Behav ; 14(4): 377-85, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25778907

RESUMEN

A major milestone of child development is the acquisition and use of speech and language. Communication disorders, including speech sound disorder (SSD), can impair a child's academic, social and behavioral development. Speech sound disorder is a complex, polygenic trait with a substantial genetic component. However, specific genes that contribute to SSD remain largely unknown. To identify associated genes, we assessed the association of the DYX2 dyslexia risk locus and markers in neurochemical signaling genes (e.g., nicotinic and dopaminergic) with SSD and related endophenotypes. We first performed separate primary associations in two independent samples - Cleveland SSD (210 affected and 257 unaffected individuals in 127 families) and Denver SSD (113 affected individuals and 106 unaffected individuals in 85 families) - and then combined results by meta-analysis. DYX2 markers, specifically those in the 3' untranslated region of DCDC2 (P = 1.43 × 10(-4) ), showed the strongest associations with phonological awareness. We also observed suggestive associations of dopaminergic-related genes ANKK1 (P = 1.02 × 10(-2) ) and DRD2 (P = 9.22 × 10(-3) ) and nicotinic-related genes CHRNA3 (P = 2.51 × 10(-3) ) and BDNF (P = 8.14 × 10(-3) ) with case-control status and articulation. Our results further implicate variation in putative regulatory regions in the DYX2 locus, particularly in DCDC2, influencing language and cognitive traits. The results also support previous studies implicating variation in dopaminergic and nicotinic neural signaling influencing human communication and cognitive development. Our findings expand the literature showing genetic factors (e.g., DYX2) contributing to multiple related, yet distinct neurocognitive domains (e.g., dyslexia, language impairment, and SSD). How these factors interactively yield different neurocognitive and language-related outcomes remains to be elucidated.


Asunto(s)
Dislexia/genética , Sitios Genéticos , Secuencias Reguladoras de Ácidos Nucleicos/genética , Trastorno Fonológico/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Humanos , Proteínas Asociadas a Microtúbulos/genética , Polimorfismo de Nucleótido Simple , Proteínas Serina-Treonina Quinasas/genética , Receptores de Dopamina D2/genética , Receptores Nicotínicos/genética
9.
Am J Clin Nutr ; 31(10 Suppl): S82-S85, 1978 10.
Artículo en Inglés | MEDLINE | ID: mdl-707397

RESUMEN

Selected characteristics of dietary fiber and associated nondigestible polysaccharides are discussed. These properties, which could alter gastrointestinal function, include particle size, solubility and viscosity, and interactions with small organic compounds, cations, salts, and proteins. The relationship between structure and the physiochemical properties is indicated.


Asunto(s)
Celulosa , Carbohidratos de la Dieta , Fibras de la Dieta , Digestión , Metales , Tamaño de la Partícula , Plantas Comestibles , Proteínas , Solubilidad , Relación Estructura-Actividad , Viscosidad
10.
Am J Med Genet ; 20(3): 443-52, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2581445

RESUMEN

The first 2,013 fetuses in 2,000 patients undergoing genetic amniocentesis at our institution were analyzed for the incidence of abnormal findings and for the safety and accuracy of the procedure. One percent of the patients were found to have aneuploid fetuses and another 1% were found to have elevated amniotic fluid concentrations of alpha-fetoprotein. Advanced maternal age was the indication for amniocentesis in 84% of the women with aneuploid fetuses. Thirty-two (1.6%) of the pregnancies ended in spontaneous abortion and 35 (1.7%) were terminated because of abnormal results of the prenatal diagnostic procedure. Our error rate was 0.15%, and tissue culture was successful in 97.7% of the procedures. During the latter part of our experience concurrent ultrasonography was utilized with the amniocentesis, resulting in a reduction in blood-tinged specimens from 15.0% to 5.2%. In experienced hands, midtrimester amniocentesis for the purpose of prenatal diagnosis of genetically determined defects is a safe, accurate, and valuable procedure for the identification of fetal abnormalities.


Asunto(s)
Amniocentesis , Anomalías Congénitas/genética , Adulto , Amniocentesis/efectos adversos , Aneuploidia , Anomalías Congénitas/diagnóstico , Errores Diagnósticos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Ultrasonografía , alfa-Fetoproteínas/análisis
11.
Clin Chim Acta ; 114(1): 11-9, 1981 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-7249368

RESUMEN

A readily detectable carbohydrate in the urine of two siblings with neuronal ceroid lipofuscinosis was found to be the blood group A trisaccharide. One child expired before blood typing was done while the other sibling was AB. This latter child excreted greater amounts of the trisaccharide than a group of blood type A subjects with different diagnoses when all the subjects were receiving whole or skim milk by nasogastric feedings. While the relevance of this observation to neuronal ceroid lipofuscinosis is unknown, it has been shown that the trisaccharide may be a major urinary carbohydrate depending on diet and blood type.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Ceroide/metabolismo , Errores Innatos del Metabolismo Lipídico/orina , Lipofuscina/metabolismo , Oligosacáridos/orina , Pigmentos Biológicos/metabolismo , Trisacáridos/orina , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino
12.
Carbohydr Res ; 328(4): 623-7, 2000 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-11093720

RESUMEN

The molecular structure of fagopyritol A1, a novel galactopyranosyl cyclitol from buckwheat seeds, was determined to be O-alpha-D-galactopyranosyl-(1 --> 3)-D-chiro-inositol by 1H and 13C NMR. Fagopyritol A1 is a positional isomer of fagopyritol B1 (O-alpha-D-galactopyranosyl-(1 --> 2)-D-chiro-inositol), representing a different series of fagopyritol oligomers. Trimethylsilyl derivatives of both compounds have similar mass spectra, but each may be identified by different abundance ratios of fragments with m/z 305/318 and 318/319.


Asunto(s)
Disacáridos/química , Resonancia Magnética Nuclear Biomolecular , Secuencia de Carbohidratos , Fagopyrum/química , Espectrometría de Masas , Semillas/química , Análisis de Secuencia
13.
J Agric Food Chem ; 48(7): 2843-7, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10898633

RESUMEN

Fagopyritols are mono-, di-, and trigalactosyl derivatives of D-chiro-inositol that accumulate in seeds of common buckwheat (Fagopyrum esculentum Moench) and may be important for seed maturation and as a dietary supplement. Fagopyritols and other soluble carbohydrates were assayed in mature groats and 11 milling fractions of common buckwheat seed. Because fagopyritols are in embryo and aleurone tissues, differences in fagopyritol concentrations reflect varying proportions of these tissues in each milling fraction. Bran milling fractions contained 6.4 g of total soluble carbohydrates per 100 g of dry weight, 55% of which was sucrose and 40% fagopyritols. Flour milling fractions had reduced fagopyritol concentration [0.7 g/100 g of dry weight total fagopyritols in the dark (Supreme) flour and 0.3 g/100 g in the light (Fancy) flours]. Fagopyritol B1 was 70% of total fagopyritols in all milling fractions. Fagopyritols were 40% of total soluble carbohydrates in groats of two cultivars of common buckwheat but 21% in groats of tartary buckwheat [Fagopyrum tataricum (L.) Gaertn.], probably a reflection of environment and genetics. A rhamnoglucoside present in tartary buckwheat was not detected in common buckwheat.


Asunto(s)
Carbohidratos/análisis , Disacáridos/análisis , Fagopyrum/química , Inositol/análisis , Manipulación de Alimentos , Semillas/química , Solubilidad
14.
Food Chem Toxicol ; 25(3): 233-9, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3570112

RESUMEN

Caprolactam (2-oxohexamethylenimine) is metabolized in the rat partly to 4-hydroxycaprolactam or the corresponding free acid. The 4-hydroxy metabolite rearranges spontaneously in acidic aqueous medium to an equilibrium mixture of which 6-amino-gamma-caprolactone is the major component and 6-amino-4-hydroxyhexanoic acid is a minor component. Approximately 16% of the caprolactam ingested daily by rats fed a diet containing 3% caprolactam was excreted as the 4-hydroxy metabolite and a small amount was excreted as the non-hydroxylated acid, 6-aminohexanoic acid. The metabolites were isolated by ion-exchange chromatography and identified by gas chromatography-mass spectroscopy and infra-red and nuclear magnetic resonance spectroscopy.


Asunto(s)
Azepinas/metabolismo , Caprolactama/metabolismo , Aminoácidos/análisis , Animales , Biotransformación , Cromatografía por Intercambio Iónico , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Masculino , Ninhidrina , Rotación Óptica , Ratas , Ratas Endogámicas , Espectrofotometría
15.
Addict Behav ; 25(2): 295-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10795955

RESUMEN

Standardized questionnaires were administered to 116 male and female undergraduates to examine how social deficits and alcohol expectancies relate to alcohol use. Participants were classified as either problem or nonproblem drinkers based on the Rutgers Collegiate Substance Abuse Screening Test. Problem drinkers reported experiencing social anxiety, shyness, and lower self-esteem to a greater extent than nonproblem drinkers. Problem drinkers also held more positive alcohol expectancies than nonproblem drinkers. Contrary to our hypotheses, however, particular types of alcohol expectancies did not interact with specific areas of social functioning to influence problem drinking. Overall, these findings suggest that problem drinkers have positive expectations about the immediate effects of alcohol consumption even though drinking is linked to long-term impairment in social functioning.


Asunto(s)
Intoxicación Alcohólica/psicología , Motivación , Ajuste Social , Estudiantes/psicología , Alcoholismo/psicología , Femenino , Humanos , Masculino , Inventario de Personalidad , Disposición en Psicología , Medio Social
16.
Adv Exp Med Biol ; 270: 311-20, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1706560

RESUMEN

Total dietary fiber (TDF) values for cereal grains, fruits, vegetables, processed foods, and purified or semi-purified dietary fiber products were determined by a new method using 8M urea and enzymes (urea enzymatic dialysis, UED, method). The results are compared with the official AOAC procedure. Soluble and insoluble dietary fiber were determined for several of these foodstuffs and compared with the NDF values. Crude protein and ash contamination was usually lower with the UED method compared with the AOAC method, particularly for samples that formed gels during ethanol precipitation. Urea and the heat stable amylase were effective in removing starch even at relatively low temperatures of the assay (50 degrees C). The new assay is relatively economical in use of equipment, enzymes, and reagents. Studies are currently in progress to minimize the assay time for the UED method while further improving its flexibility and robustness. The results of the studies will be discussed.


Asunto(s)
Amilasas , Fibras de la Dieta/análisis , Endopeptidasas , Análisis de los Alimentos/métodos , Urea , Diálisis , Grano Comestible/análisis , Frutas/análisis , Solubilidad , Almidón/análisis , Verduras/análisis
17.
J Natl Med Assoc ; 77(2): 139-41, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3981648

RESUMEN

The emergence of antibiotic-resistant bacteria is a serious threat to public health. Infectious drug resistance, the transmission of resistant determinants from antibiotic-resistant bacteria to antibiotic-sensitive bacterial populations, creates clinical problems that must be addressed. Adequate knowledge of the mechanisms responsible for bacteria resistance is important for ensuring the benefits of antimicrobial therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Farmacorresistencia Microbiana , Humanos
18.
J Speech Lang Hear Res ; 40(4): 708-22, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9263938

RESUMEN

Research in normal and disordered phonology requires measures of speech production that are biolinguistically appropriate and psychometrically robust. Their conceptual and numeric properties must be well characterized, particularly because speech measures are increasingly appearing in large-scale epidemiologic, genetic, and other descriptive-explanatory database studies. This work provides a rationale for extensions to an articulation competence metric titled the Percentage of Consonants Correct [PCC; Shriberg & Kwiatkowski, 1982; Shriberg, Kwiatkowski, Best, Hengst, & Terselic-Weber, 1986], which is computed from a 5- to 10-minute conversational speech sample. Reliability and standard error of measurement estimates are provided for 9 of a set of 10 speech metric including the PCC. Discussion includes rationale for selecting one or more of the 10 metrics for specific clinical and research needs.


Asunto(s)
Trastornos de la Articulación/diagnóstico , Fonética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Distribución Aleatoria , Reproducibilidad de los Resultados , Medición de la Producción del Habla
19.
J Speech Lang Hear Res ; 40(4): 723-40, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9263939

RESUMEN

A companion paper includes rationale for the use of 10 metrics of articulation competence in conversational speech (Shriberg, Austin Lewis, McSweeny, & Wilson, 1997). The present paper reports lifespan reference data for these measures using records from a total of 836 3- to 40(+)-year-old speakers with normal and disordered speech. The reference data are subdivided by diagnostic classification based on extensions to an instrument titled the Speech Disorders Classification System (SDCS; Shriberg, 1993). Appendices provide procedural information on the SDCS and statistical rationale for the reference data.


Asunto(s)
Trastornos del Habla/clasificación , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Medición de la Producción del Habla
20.
Am J Dent ; 5(2): 69-72, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1524749

RESUMEN

The compressive strengths and compressive moduli of seven base materials (Dycal, VLC Dycal, Time-line, Vitrabond, Ketac Bond, Fuji Lining LC, XR-Ionomer) were measured at 7 minutes, 24 hours, and 90 days using 9 mm by 4 mm cylindrical specimens prepared in hollow Teflon tubes. The 24-hour and 90-day specimens were maintained for 1 hour at 37 degrees C with relative humidity greater than 30%, then placed in distilled water at 37 degrees C until testing. After grinding the ends of the specimens flat, the cylinders of base material were loaded at 1.0 mm/min in an Instron. The compressive strengths of Timeline, a resin based material, at 7 minutes, 24 hours, and 90 days were not significantly different. Timeline had significantly greater compressive strengths of all time periods than the other six materials. The compressive strength of both Dycal and VLC Dycal decreased significantly between the 24-hour and 90-day periods. Of the three photosensitive GI base/liners tested, Fuji Lining LC had significantly higher compressive strengths in all three time periods. At 7 minutes, Timeline demonstrated a significantly higher compressive modulus than any other product. Ketac Bond had a significantly higher compressive modulus at 24 hours and 90 days.


Asunto(s)
Hidróxido de Calcio/química , Recubrimiento de la Cavidad Dental , Cementos de Ionómero Vítreo/química , Metacrilatos/química , Poliuretanos/química , Análisis de Varianza , Resinas Compuestas/química , Elasticidad , Ensayo de Materiales , Minerales/química , Presión , Fluoruro de Sodio/química , Resistencia a la Tracción , Factores de Tiempo , Uretano/análogos & derivados , Uretano/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA