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Kevin Williams

Publications and source records attributed to Kevin Williams.

7 recordsLinked to original sources
PubMed2005

Look who's being left behind: educational interpreters and access to education for deaf and hard-of-hearing students.

For many deaf and hard-of-hearing students, access to the general education curriculum is provided, in part, by using the services of an educational interpreter. Even with a highly qualified interpreter, full access to the content and social life in a hearing classroom can be challenging, and there are many aspects of the educational placement that can affect success. The skills and knowledge of the educational interpreter are one critical aspect. This study reports results from a study of approximately 2,100 educational interpreters from across the United States. All the interpreters were evaluated using the Educational Interpreters Performance Assessment (EIPA), an evaluation instrument used to assess and certify classroom interpreters (see Schick, Williams, & Bolster, 1999). The results show that approximately 60% of the interpreters evaluated had inadequate skills to provide full access. In addition, educational interpreters who had completed an Interpreter Training Program had EIPA scores only .5 of an EIPA level above those who had not, on average. Demographic data and its relationship with EIPA ratings are explored. In general, the study suggests that many deaf and hard-of-hearing students receive interpreting services that will seriously hinder reasonable access to the classroom curriculum and social interaction.

Adult↗
PubMed2004

Two TIR:NB:LRR genes are required to specify resistance to Peronospora parasitica isolate Cala2 in Arabidopsis.

Resistance responses that plants deploy in defence against pathogens are often triggered following a recognition event mediated by resistance (R) genes. The encoded R proteins usually contain a nucleotide-binding site (NB) and a leucine-rich repeat (LRR) domain. They are further classified into those that contain an N-terminal coiled coil (CC) motif or a Toll interleukin receptor (TIR) domain. Such R genes, when transferred into a susceptible plant of the same or closely related species, usually impart full resistance capability. We have used map-based cloning and mutation analysis to study the recognition of Peronospora parasitica (RPP)2 (At) locus in Arabidopsis accession Columbia (Col-0), which is a determinant of specific recognition of P. parasitica (At) isolate Cala2. Genetic mapping located RPP2 to a 200-kb interval on chromosome 4, which contained four adjacent TIR:NB:LRR genes. Mutational analysis revealed three classes of genes involved in specifying resistance to Cala2. One class, which resulted in pleiotropic effects on resistance to other P. parasitica (At) isolates, was unlinked to the RPP2 locus; this class included AtSGT1b. The other two classes were mapped within the interval and were specific to Cala2 resistance. Representatives of each of these classes were sequenced, and mutations were found in one or the other of two (RPP2A and RPP2B) of the four TIR:NB:LRR genes. RPP2A and RPP2B complemented their specific mutations, but failed to impart resistance when present alone, and it is concluded that both genes are essential determinants for isolate-specific recognition of Cala2. RPP2A has an unusual structure with a short LRR domain at the C-terminus, preceded by two potential but incomplete TIR:NB domains. In addition, the RPP2A LRR domain lacks conserved motifs found in all but three other TIR:NB:LRR class proteins. In contrast, RPP2B has a complete TIR:NB:LRR structure. It is concluded that RPP2A and RPP2B cooperate to specify Cala2 resistance by providing recognition or signalling functions lacked by either partner protein.

Amino Acid Sequence↗
PubMed2003

A Nodal- and ALK4-independent signaling pathway activated by Cripto-1 through Glypican-1 and c-Src.

Human Cripto-1 (CR-1) is a member of the epidermal growth factor-Cripto FRL1 Cryptic family that has been shown to function as a coreceptor with the type I Activin serine-threonine kinase receptor ALK4 for the transforming growth factor beta-related peptide Nodal. However, CR-1 can also activate the mitogen-activated protein kinase and Akt pathways independently of Nodal and ALK4 by an unknown mechanism. Here, we demonstrate that CR-1 specifically binds to Glypican-1, a membrane-associated heparan sulfate proteoglycan, and activates the tyrosine kinase c-Src, triggering the mitogen-activated protein kinase and Akt signaling pathways. Finally, an active Src kinase is necessary for CR-1 to induce in vitro transformation and migration in mouse mammary epithelial cells.

Activin Receptors, Type I↗
PubMed2003

An unusual H-Ras mutant isolated from a human multiple myeloma line leads to transformation and factor-independent cell growth.

Multiple myeloma (MM) is an incurable plasma cell malignancy. To investigate biochemical lesions associated with MM, we constructed an expression cDNA library from the OPM-2 human myeloma line. A highly transforming H-Ras mutant was identified by transfection analysis using NIH 3T3 cells. DNA sequencing demonstrated a single-point mutation at position 117 located in the guanine nucleotide-binding site resulting in a lysine-to-glutamic acid substitution. This mutant, H-Ras (K117E), was found to be constitutively activated in terms of GTP binding. We compared the biological effects of H-Ras (K117E) and H-Ras (G12V) in 32D murine hematopoietic progenitor cells. Whereas both Ras proteins are constitutively activated, 32D cells expressing H-Ras (G12V) are still dependent on IL-3 for survival and proliferation while cells carrying H-Ras (K117E) become IL-3 independent. Similar experiments conducted with the B9 line, an IL-6-dependent hybridoma, also demonstrated that B9/H-Ras (K117E) became IL-6-independent. Expression of H-Ras (K117E) in the human IL-6-dependent ANBL-6 myeloma line resulted in enhanced proliferation at suboptimal concentrations of IL-6. These observations suggest that H-Ras mutations at the binding site for the GTP nucleotide ring structure may also represent activating lesions and have additional biological effects when compared to previously described Ras mutants.

Animals↗
PubMed2002

Assessment of the intrarater and interrater reliability of an established clinical task analysis methodology.

BACKGROUND: Task analysis may be useful for assessing how anesthesiologists alter their behavior in response to different clinical situations. In this study, the authors examined the intraobserver and interobserver reliability of an established task analysis methodology. METHODS: During 20 routine anesthetic procedures, a trained observer sat in the operating room and categorized in real-time the anesthetist's activities into 38 task categories. Two weeks later, the same observer performed task analysis from videotapes obtained intraoperatively. A different observer performed task analysis from the videotapes on two separate occasions. Data were analyzed for percent of time spent on each task category, average task duration, and number of task occurrences. Rater reliability and agreement were assessed using intraclass correlation coefficients. RESULTS: Intrarater reliability was generally good for categorization of percent time on task and task occurrence (mean intraclass correlation coefficients of 0.84-0.97). There was a comparably high concordance between real-time and video analyses. Interrater reliability was generally good for percent time and task occurrence measurements. However, the interrater reliability of the task duration metric was unsatisfactory, primarily because of the technique used to capture multitasking. CONCLUSIONS: A task analysis technique used in anesthesia research for several decades showed good intrarater reliability. Off-line analysis of videotapes is a viable alternative to real-time data collection. Acceptable interrater reliability requires the use of strict task definitions, sophisticated software, and rigorous observer training. New techniques must be developed to more accurately capture multitasking. Substantial effort is required to conduct task analyses that will have sufficient reliability for purposes of research or clinical evaluation.

Adult↗
PubMed2000

Comprehending disclosure: must patients understand the risks they run?

It is well known that competent patients must be told about the risks of proposed medical procedures. This paper argues that recent professional guidelines and the law of negligence now take matters further by requiring doctors to take reasonable steps in an attempt to ensure that patients understand the risks they are being invited to run, so facilitating meaningful choices and the opportunity to give a properly informed consent.

Canada↗