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1.
Metacogn Learn ; 18(1): 135-163, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36065225

RESUMEN

The Self-Regulation for Learning Online (SRL-O) questionnaire was developed to encompass the breadth of motivational beliefs and learning strategies that are often used in online and/or blended learning contexts. No current measure meets all these needs. This study used two non-duplicate samples to provide evidence of the psychometric properties of SRL-O using exploratory factor analyses (sample 1, n = 313), and confirmatory factor analyses, convergent and content validity and reliability (sample 2, n = 321). The SRL-O has a 10-factor structure, made up of (1) online self-efficacy, (2) online intrinsic motivation, (3) online extrinsic motivation, (4) online negative achievement emotion, (5) planning and time management, (6) metacognition, (7) study environment, (8) online effort regulation, (9) online social support, and (10) online task strategies. The SRL-O was also found to have two superordinate factors (motivational beliefs and learning strategies). The SRL-O was demonstrated to be a psychometrically sound measure of online SRL for learners studying in online and blended learning contexts. There is no other online self-regulated learning questionnaire that currently covers such a wide range of motivational beliefs and learning strategies.

2.
Biotechniques ; 27(1): 94-6, 98, 100-2 passim, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10407671

RESUMEN

We have devised a general method for producing vector-insensitive probes from clones in which insert DNA (ca. 40 kb) could not be amplified in one piece nor be excised from the vector sequence. The method involves PCR and vector-specific primers in combination with restriction digestion and ligation. It yields specific PCR products that could subsequently be labeled using DIG-11-dUTP in a single-cycle PCR. In colony blot hybridization, the probes were specific for the insert DNA from which the probe was derived and, importantly, did not detect vector sequences.


Asunto(s)
Cósmidos/genética , Sondas de ADN/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Southern Blotting , Clonación Molecular , ADN Bacteriano/genética , Desoxirribonucleasa EcoRI , Desoxirribonucleasas de Localización Especificada Tipo II , Nucleótidos de Desoxiuracil , Didesoxinucleótidos , Digoxigenina/análogos & derivados , Biblioteca de Genes , Indicadores y Reactivos , Hibridación de Ácido Nucleico , Salmonella typhimurium/genética
3.
FEMS Microbiol Lett ; 170(2): 355-61, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9933930

RESUMEN

We have constructed a DNA library from a virulent Salmonella typhimurium strain, in an avirulent strain. The process of selecting the components of interest from the library involved iterative growth in liquid culture. This resulted, after four cycles, in the culture becoming homogeneous for a single plasmid, which was much smaller than the average size for the library. We have identified the larger precursor of this plasmid which has two regions of sufficient homology to allow recombination resulting in the formation of the small plasmid. S. typhimurium carrying the small plasmid have a smaller genetic burden than other members of the library and survive better in spent culture medium, facilitating selection on repeated subculture. Such rapid adventitious selection has important implications for isolation of clones of interest from genomic libraries.


Asunto(s)
Cósmidos/genética , Biblioteca Genómica , Salmonella typhimurium/genética , ADN Bacteriano/análisis , Mapeo Restrictivo , Salmonella typhimurium/crecimiento & desarrollo , Salmonella typhimurium/patogenicidad , Virulencia
5.
Biochem J ; 272(3): 627-31, 1990 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-2125210

RESUMEN

The chromosomal gene from Pseudomonas aeruginosa encoding beta-lactamase has been cloned, and the sequence determined and compared with corresponding sequences of beta-lactamases from members of the enterobacteriaceae. Upstream of the beta-lactamase gene is an open reading frame which we postulate encodes a regulatory protein, AmpR. We identified a helix-turn-helix region in AmpR and a putative AmpR-binding site.


Asunto(s)
Genes Bacterianos , Genes Reguladores , Pseudomonas aeruginosa/genética , beta-Lactamasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Pseudomonas aeruginosa/enzimología , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico
6.
J Bacteriol ; 165(2): 353-6, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2935522

RESUMEN

The influence of the growth rate on outer membrane protein composition and enterobactin production was studied with Klebsiella pneumoniae grown under conditions of iron limitation in chemostats. More enterobactin was produced at fast (D = 0.4 h-1) and slow (D = 0.1 h-1) growth rates in continuous cultures than in either logarithmic- or stationary-phase batch cultures. When the growth rate was controlled under conditions of carbon limitation and the iron level was reduced to 0.5 microM, the iron-regulated outer membrane proteins and enterobactin were induced at the fast growth rate. At the slow growth rate, although the iron-regulated outer membrane proteins were barely visible, a significant level of enterobactin was still produced. These results suggest that under conditions of either carbon or iron limitation, the growth rate can influence the induction of the high-affinity iron uptake system of K. pneumoniae. Other outer membrane proteins, including a 39-kilodalton peptidoglycan-associated protein, were found to vary with the growth rate and nutrient limitation.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/biosíntesis , Enterobactina/biosíntesis , Hierro/metabolismo , Klebsiella pneumoniae/crecimiento & desarrollo , Serina/análogos & derivados , Carbono/metabolismo , Klebsiella pneumoniae/metabolismo , Peso Molecular , Peptidoglicano/metabolismo
7.
J Speech Hear Disord ; 46(3): 317-20, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7278179

RESUMEN

The subject in this project wa a 24-year-old moderately retarded institutionalized woman who displayed a variety of inappropriate social behaviors including an abnormally loud vocal volume. A reinforcement program was established in which each teaching session contained 50 opportunities for the subject to respond below an absolute intensity level of 65 dB. The initial treatment procedure used the reveal (ABAB) teaching/research design. Continuous social and edible reinforcement, coupled with activation of a Whisperlite, served as positive/negative reinforcers. Visual and verbal cues were used to facilitate the emission of correct responses. During the second intervention, the desired behavior was maintained at the criterion of 50 independent responses below 65 dB for three consecutive sessions. Three follow-up sessions showed that the subject maintained 100% accuracy in responding below 65 dB in a conversation.


Asunto(s)
Discapacidad Intelectual/complicaciones , Refuerzo en Psicología , Trastorno de la Conducta Social/terapia , Voz , Adulto , Señales (Psicología) , Desinstitucionalización , Femenino , Estudios de Seguimiento , Generalización Psicológica , Humanos
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