64 research outputs found
Plastisol Foaming Process. Decomposition of the Foaming Agent, Polymer Behavior in the Corresponding Temperature Range and Resulting Foam Properties
The decomposition of azodicarbonamide, used as foaming agent in PVC - plasticizer (1/1) plastisols was studied by DSC. Nineteen different plasticizers, all belonging to the ester family, two being polymeric (polyadipates), were compared. The temperature of maximum decomposition rate (in anisothermal regime at 5 K min-1 scanning rate), ranges between 434 and 452 K. The heat of decomposition ranges between 8.7 and 12.5 J g -1. Some trends of variation of these parameters appear significant and are discussed in terms of solvent (matrix) and viscosity effects on the decomposition reactions. The shear modulus at 1 Hz frequency was determined at the temperature of maximum rate of foaming agent decomposition, and differs significantly from a sample to another. The foam density was determined at ambient temperature and the volume fraction of bubbles was used as criterion to judge the efficiency of the foaming process. The results reveal the existence of an optimal shear modulus of the order of 2 kPa that corresponds roughly to plasticizer molar masses of the order of 450 ± 50 g mol-1. Heavier plasticizers, especially polymeric ones are too difficult to deform. Lighter plasticizers such as diethyl phthalate (DEP) deform too easily and presumably facilitate bubble collapse
Loss of Function of the Cik1/Kar3 Motor Complex Results in Chromosomes with Syntelic Attachment That Are Sensed by the Tension Checkpoint
The attachment of sister kinetochores by microtubules emanating from opposite spindle poles establishes chromosome bipolar attachment, which generates tension on chromosomes and is essential for sister-chromatid segregation. Syntelic attachment occurs when both sister kinetochores are attached by microtubules from the same spindle pole and this attachment is unable to generate tension on chromosomes, but a reliable method to induce syntelic attachments is not available in budding yeast. The spindle checkpoint can sense the lack of tension on chromosomes as well as detached kinetochores to prevent anaphase onset. In budding yeast Saccharomyces cerevisiae, tension checkpoint proteins Aurora/Ipl1 kinase and centromere-localized Sgo1 are required to sense the absence of tension but are dispensable for the checkpoint response to detached kinetochores. We have found that the loss of function of a motor protein complex Cik1/Kar3 in budding yeast leads to syntelic attachments. Inactivation of either the spindle or tension checkpoint enables premature anaphase entry in cells with dysfunctional Cik1/Kar3, resulting in co-segregation of sister chromatids. Moreover, the abolished Kar3-kinetochore interaction in cik1 mutants suggests that the Cik1/Kar3 complex mediates chromosome movement along microtubules, which could facilitate bipolar attachment. Therefore, we can induce syntelic attachments in budding yeast by inactivating the Cik1/Kar3 complex, and this approach will be very useful to study the checkpoint response to syntelic attachments
Intervenir sobre la cultura organizacional: ¿qué aspectos se pueden considerar?
La cultura organizacional (co) es un macroconstructo que involucra una gran variedad de componentes y funciones organizacionales (Warner, 2014). Reyes y Moros (2018) señalan que tiene su origen en el estudio realizado en Hawthorne por Elton Mayo y otros investigadores de la Escuela de las Relaciones Humanas de la AdministraciĂłn, en el que buscaban identificar la influencia de las condiciones fĂsicas y ambientales en el desempeño individual. Para Reyes y Moros (2018), la co se siguiĂł desarrollando en los años setenta con Pettigrew, para ser entendida como un sistema de significados que tanto pĂşblica como colectivamente es aceptado para operar en un tiempo y por un grupo determinado. Los autores la definen como “… un sistema de significados compartidos por los miembros de la organizaciĂłn, los cuales son el resultado de una construcciĂłn social constituida a travĂ©s de sĂmbolos y como tal deben ser interpretados”1a ediciĂł
Comprehensive molecular characterization of the hippo signaling pathway in cancer
Hippo signaling has been recognized as a key tumor suppressor pathway. Here, we perform a comprehensive molecular characterization of 19 Hippo core genes in 9,125 tumor samples across 33 cancer types using multidimensional “omic” data from The Cancer Genome Atlas. We identify somatic drivers among Hippo genes and the related microRNA (miRNA) regulators, and using functional genomic approaches, we experimentally characterize YAP and TAZ mutation effects and miR-590 and miR-200a regulation for TAZ. Hippo pathway activity is best characterized by a YAP/TAZ transcriptional target signature of 22 genes, which shows robust prognostic power across cancer types. Our elastic-net integrated modeling further reveals cancer-type-specific pathway regulators and associated cancer drivers. Our results highlight the importance of Hippo signaling in squamous cell cancers, characterized by frequent amplification of YAP/TAZ, high expression heterogeneity, and significant prognostic patterns. This study represents a systems-biology approach to characterizing key cancer signaling pathways in the post-genomic era
Response to depression treatment in the Aging Brain Care Medical Home model
Michael A LaMantia,1–4 Anthony J Perkins,5,6 Sujuan Gao,2,7 Mary G Austrom,8,9 Cathy A Alder,10 Dustin D French,11,12 Debra K Litzelman,2,3,13 Ann H Cottingham,3 Malaz A Boustani1–3,5 1Indiana University Center for Aging Research, 2Regenstrief Institute, Inc., 3Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, 4Department of Medicine, University of Vermont College of Medicine, Burlington, VT, 5Indiana University Center for Health Innovation and Implementation Science, 6Indiana Clinical and Translational Sciences Institute, 7Department of Biostatistics, Indiana University School of Medicine, 8Department of Psychiatry, Indiana University School of Medicine, 9Indiana University Alzheimer’s Disease Center, 10Eskenazi Health, Indianapolis, IN, 11Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, 12Veterans Affairs Health Services Research and Development Service, Chicago, IL, 13Indiana University Center for Health Services and Outcomes Research, Indianapolis, IN, USA Objective: To evaluate the effect of the Aging Brain Care (ABC) Medical Home program’s depression module on patients’ depression severity measurement over time.Design: Retrospective chart review.Setting: Public hospital system.Participants: Patients enrolled in the ABC Medical Home program between October 1, 2012 and March 31, 2014.Methods: The response of 773 enrolled patients who had multiple patient health questionnaire-9 (PHQ-9) scores recorded in the ABC Medical Home program’s depression care protocol was evaluated. Repeatedly measured PHQ-9 change scores were the dependent variables in the mixed effects models, and demographic and comorbid medical conditions were tested as potential independent variables while including random effects for time and intercept.Results: Among those patients with baseline PHQ-9 scores >10, there was a significant decrease in PHQ-9 scores over time (P<0.001); however, the effect differed by gender (P=0.015). On average, women’s scores (4.5 point drop at 1 month) improved faster than men’s scores (1 point drop at 1 month). Moreover, both men and women had a predicted drop of 7 points (>50% decline from baseline) on the PHQ-9 at 6 months. Conclusion: These analyses demonstrate evidence for the sustained effectiveness of the ABC Medical Home program at inducing depression remission outcomes while employing clinical staff who required less formal training than earlier clinical trials. Keywords: geriatrics, care coordination, Medicar
The Culture of Academic Medicine: Faculty Behaviors Impacting the Learning Environment
ObjectiveThe culture of academic medical institutions impacts trainee education, among many other faculty and patient outcomes. Disrespectful behavior by faculty is one of the most challenging and common problems that, left unattended, disrupts healthy work and learning environments. Conversely, a respectful environment facilitates learning, creates a sense of safety, and rewards professionalism. The authors developed surveys and an intervention in an effort to better understand and improve climate concerns among health sciences faculty at the University of California, San Diego (UCSD), a research-intense, public, academic medical center.MethodsAn online "climate survey" of all UC San Diego health sciences faculty was conducted in 2011-2012. A strategic campaign to address the behavioral issues identified in the initial survey was subsequently launched. In 2015, the climate was re-evaluated in order to assess the effectiveness of the intervention.ResultsA total of 478 faculty members (223 women, 235 men, 35 % of faculty) completed the baseline survey, reporting relatively low levels of observed sexual harassment (7 %). However, faculty reported concerning rates of other disruptive behaviors: derogatory comments (29 %), anger outbursts (25 %), and hostile communication (25 %). Women and mid-level faculty were more likely to report these behavioral concerns than men and junior or senior colleagues. Three years after an institutional strategy was initiated, 729 faculty members (50 % of the faculty) completed a follow-up survey. The 2015 survey results indicate significant improvement in numerous climate factors, including overall respectful behaviors, as well as behaviors related to gender.ConclusionsIn order to enhance a culture of respect in the learning environment, institutions can effectively engage academic leaders and faculty at all levels to address disruptive behavior and enhance positive climate factors
Career Development as a Long-distance Hike
Traditional images of achievement do not capture today’s more complex career development realities. Approaching career development as a long-distance expedition can help professionals in addressing the strenuous challenges they face, in seeing that a career can be built in many ways, and in taking a long-term view of their journeys. Skills are like muscles, self-efficacy is like sturdy boots, advancement “how-to’s” are like maps, and mentors are like trail guides. Among the tasks each hiker faces are selecting destinations, navigating through rough terrain and weather, and balancing their packs. To further their hikers’ resilience, departments should pay more attention to the career development ecology, including improving access to qualified trail guides and to alternate paths
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