Recent Decisions

Comments on recent decisions by Joseph V. Stodola, Kenneth J. Konop, John H. Tuberty, William M. Cain, John D. Voss, Alvin G. Kolski, and W. D. Rollison

¿Qué son los Saberes Tecnológicos y Pedagógicos del Contenido (TPACK)?

This paper describes a teacher knoledge framework for technology integration called technological pedagogical content knowledge (originall TPCK, now knows as TPACK, or technology, pedagogy, and content knowledge). This framework builds on Lee Shilman’s (1986, 1987) construct of pedagogical content knowledge (PCK) to include technology knowledge. The development of TPACK by teachers is critical to effective teaching with technology. The paper begins with a brief instroducction to the complex ill structure nature of teaching. The nature of technologies (both analog and digital) is considered, as well as how the inclusion of technology in pedagogy further complicates teaching. The TPACK framework for teacher knowledge is drescribed in detail as a complex interacction among three bodies of knowledge: content, pedagogy, and technology. The interaction of these bodies of knowledge, both theoretically and in practice, produces the types of flexible knowledge needed to successfully intregrate technology use into teaching.Este artículo describe un marco de saberes docente para la integración de la tecnología denominado  “Conocimiento Tecnológico y Pedagógico del Contenido”(originalmente TPCK, conocido como TPACK, Tecnología, Pedagogía y Conocimiento del Contenido). Este marco se basa en la construcción de Lee Shulman (1986, 1987) sobre Contenidos del Conocimiento Pedagógico (PCK) para incluir conocimientos tecnológicos. El desarrollo de TPACK por parte de los y las docentes es crítico para la enseñanza efectiva con tecnología. Este artículo comienza con una breve introducción a la compleja y débilmente estructurada naturaleza de la enseñanza. Se considera también la naturaleza de las tecnologías (ambas análogas y digital) como así también cómo la inclusión de la tecnología en la pedagogía complejiza la enseñanza. El marco TPACK para conocimientos docentes es decripto en detalle como una compleja interacción entre tres cuerpos de conocimientos: del contenido a enseñar, pedagógico y tecnológico. La interacción de estos tres cuerpos de saberes, tanto en teoría como en la práctica, produce el tipo de conocimiento flexible necesario para integrar exitosamente el uso de la tecnología en la enseñanza

Histotripsy Homogenization of the Prostate: Thresholds for Cavitation Damage of Periprostatic Structures

Background and Purpose: Histotripsy is a noninvasive, pulsed ultrasound technology that produces mechanically homogenized tissue within targeted volumes. Previous work has demonstrated prostatic tissue debulking in a canine model. The aim was to establish safety thresholds by evaluating histologic changes of urinary sphincter, neurovascular bundle (NVB), and rectum after targeted histotripsy treatment of these critical structures. Materials and Methods: Rectum, urinary sphincter, and NVB in five anesthetized canines were targeted for histotripsy treatment (50 total points). Locations received 1k, 10k, or 100k acoustic pulses (4 microsecond, 1-MHz) at a repetition frequency of 500-Hz. Canine subjects were euthanized immediately (2), survived 3 days (1), or 2 weeks (3) after treatment. Prostates, periprostatic tissue, and rectum were harvested and processed for histology. Results: The sphincter was structurally intact with minimal muscle fiber disruption even after 100k pulses (n=10). Undamaged nerves, arteries, and veins of the NVB were seen despite mechanical homogenization of surrounding loose connective tissue (n=19). The rectum, however, exhibited dose-dependent damage (n=20). 1k pulses yielded mild submucosal hemorrhage. 10k pulses resulted in moderate collagen disruption and focal mucosal homogenization. 100k pulses produced damage to the mucosa and muscularis propria with extensive hemorrhage and collagen disruption. One canine treated with 100k pulses needed early euthanasia (day 3) because of complications from a urine leak. Conclusions: Histotripsy histologic tissue effect varied based on targeted structure with substantial structural preservation of NVB and sphincter. Rectal subclinical damage was apparent after 1k pulses and increased in extent and severity with escalating doses. Future work will include assessment of functional outcomes and refinement of these initial safety thresholds.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90446/1/end-2E2010-2E0648.pd