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Sample records for fibroblasts self-direct multicellular

  1. Cardiac fibroblasts support endothelial cell proliferation and sprout formation but not the development of multicellular sprouts in a fibrin gel co-culture model.

    PubMed

    Twardowski, Rachel L; Black, Lauren D

    2014-05-01

    A primary impediment to cardiac tissue engineering lies in the inability to adequately vascularize the constructs to optimize survival upon implantation. During normal angiogenesis, endothelial cells (ECs) require a support cell to form mature patent lumens and it has been demonstrated that pericytes, vascular smooth muscle cells and mesenchymal stem cells (MSCs) are all able to support the formation of mature vessels. In the heart, cardiac fibroblasts (CFs) provide important electrical and mechanical functions, but to date have not been sufficiently studied for their role in angiogenesis. To study CFs role in angiogenesis, we co-cultured different concentrations of various cell types in fibrin hemispheres with appropriate combinations of their specific media, to determine the optimal conditions for EC growth and sprout formation through DNA analysis, flow cytometry and immunohistology. ECs proliferated best when co-cultured with CFs and analysis of immunohistological images demonstrated that ECs formed the longest and most numerous sprouts with CFs as compared to MSCs. However, ECs were able to produce more multicellular sprouts when in culture with the MSCs. Moreover, these effects were dependent on the ratio of support cell to EC in co-culture. Overall, CFs provide a good support system for EC proliferation and sprout formation; however, MSCs allow for more multicellular sprouts, which is more indicative of the in vivo process.

  2. Cardiac Fibroblasts Support Endothelial Cell Proliferation and Sprout Formation but not the Development of Multicellular Sprouts in a Fibrin Gel Co-Culture Model

    PubMed Central

    Twardowski, Rachel L.; Black, Lauren D.

    2014-01-01

    A primary impediment to cardiac tissue engineering lies in the inability to adequately vascularize the constructs to optimize survival upon implantation. During normal angiogenesis, endothelial cells (ECs) require a support cell to form mature patent lumens and it has been demonstrated that pericytes, vascular smooth muscle cells and mesenchymal stem cells (MSCs) are all able to support the formation of mature vessels. In the heart, cardiac fibroblasts (CFs) provide important electrical and mechanical functions, but to date have not been sufficiently studied for their role in angiogenesis. To study CFs role in angiogenesis, we co-cultured different concentrations of various cell types in fibrin hemispheres with appropriate combinations of their specific media, to determine the optimal conditions for EC growth and sprout formation through DNA analysis, flow cytometry and immunohistology. ECs proliferated best when co-cultured with CFs and analysis of immunohistological images demonstrated that ECs formed the longest and most numerous sprouts with CFs as compared to MSCs. However, ECs were able to produce more multicellular sprouts when in culture with the MSCs. Moreover, these effects were dependent on the ratio of support cell to EC in co-culture. Overall, CFs provide a good support system for EC proliferation and sprout formation; however, MSCs allow for more multicellular sprouts, which is more indicative of the in vivo process. PMID:24435656

  3. Synthetic multicellularity.

    PubMed

    Maharbiz, Michel M

    2012-12-01

    The ability to synthesize biological constructs on the scale of the organisms we observe unaided is probably one of the more outlandish, yet recurring, dreams humans have had since they began to modify genes. This review brings together recent developments in synthetic biology, cell and developmental biology, computation, and technological development to provide context and direction for the engineering of rudimentary, autonomous multicellular ensembles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Self-Directed Workplace Learning.

    ERIC Educational Resources Information Center

    1998

    This document contains four papers from a symposium on self-directed workplace learning. "Self-Directed Work Teams: Implementation and Performance" (Marcel van der Klink, Hilde ter Horst) discusses the results of a study examining the implementation and effects of self-directed work teams in a land register office and the role of the…

  5. Self-Directed Workplace Learning.

    ERIC Educational Resources Information Center

    1998

    This document contains four papers from a symposium on self-directed workplace learning. "Self-Directed Work Teams: Implementation and Performance" (Marcel van der Klink, Hilde ter Horst) discusses the results of a study examining the implementation and effects of self-directed work teams in a land register office and the role of the…

  6. Experimental evolution of multicellularity

    PubMed Central

    Ratcliff, William C.; Denison, R. Ford; Borrello, Mark; Travisano, Michael

    2012-01-01

    Multicellularity was one of the most significant innovations in the history of life, but its initial evolution remains poorly understood. Using experimental evolution, we show that key steps in this transition could have occurred quickly. We subjected the unicellular yeast Saccharomyces cerevisiae to an environment in which we expected multicellularity to be adaptive. We observed the rapid evolution of clustering genotypes that display a novel multicellular life history characterized by reproduction via multicellular propagules, a juvenile phase, and determinate growth. The multicellular clusters are uniclonal, minimizing within-cluster genetic conflicts of interest. Simple among-cell division of labor rapidly evolved. Early multicellular strains were composed of physiologically similar cells, but these subsequently evolved higher rates of programmed cell death (apoptosis), an adaptation that increases propagule production. These results show that key aspects of multicellular complexity, a subject of central importance to biology, can readily evolve from unicellular eukaryotes. PMID:22307617

  7. Stabilizing multicellularity through ratcheting

    PubMed Central

    Libby, Eric; Conlin, Peter L.; Kerr, Ben; Ratcliff, William C.

    2016-01-01

    The evolutionary transition to multicellularity probably began with the formation of simple undifferentiated cellular groups. Such groups evolve readily in diverse lineages of extant unicellular taxa, suggesting that there are few genetic barriers to this first key step. This may act as a double-edged sword: labile transitions between unicellular and multicellular states may facilitate the evolution of simple multicellularity, but reversion to a unicellular state may inhibit the evolution of increased complexity. In this paper, we examine how multicellular adaptations can act as evolutionary ‘ratchets’, limiting the potential for reversion to unicellularity. We consider a nascent multicellular lineage growing in an environment that varies between favouring multicellularity and favouring unicellularity. The first type of ratcheting mutations increase cell-level fitness in a multicellular context but are costly in a single-celled context, reducing the fitness of revertants. The second type of ratcheting mutations directly decrease the probability that a mutation will result in reversion (either as a pleiotropic consequence or via direct modification of switch rates). We show that both types of ratcheting mutations act to stabilize the multicellular state. We also identify synergistic effects between the two types of ratcheting mutations in which the presence of one creates the selective conditions favouring the other. Ratcheting mutations may play a key role in diverse evolutionary transitions in individuality, sustaining selection on the new higher-level organism by constraining evolutionary reversion. This article is part of the themed issue ‘The major synthetic evolutionary transitions’. PMID:27431522

  8. Self directed and lifelong learning.

    PubMed

    Alexander, Sylvia; Kernohan, George; McCullagh, Paul

    2004-01-01

    Given the many changes that occur in medicine, health care and information technologies we need to prepare all our students to engage in self directed and life long learning. There is considerable opportunity for self-directed and lifelong learning in health informatics bringing together students in exciting global learning environments, where they have much greater freedom and flexibility in their studies and potentially a wider variety of resources available to them. Self-directed learning focuses on the process by which adults take control of their own learning, in particular how they set their own learning goals, locate appropriate resources, decide on which learning methods to use and evaluate their progress. Lifelong learning happens in a variety of formal and informal settings building on both intentional and incidental learning experiences. In a lifelong learning situation the tutor must relinquish the role of expert and assume the role of facilitator, guiding learners to uncover their own knowledge. Against a back drop of rapid advances in technology which can be used to both deliver course materials and provide enhanced learning opportunities, this chapter outlines the pedagogic principles and practices which underpin self-directed and lifelong learning.

  9. Expanding Horizons in Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    The following papers are included: "Preface" (Huey B. Long); "Self-Directed Learning: Smoke and Mirrors?" (Huey B. Long); "From Self-Culture to Self-Direction: An Historical Analysis of Self-Directed Learning" (Amy D. Rose); "The Link between Self-Directed and Transformative Learning" (Jane Pilling-Cormick);…

  10. Expanding Horizons in Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    The following papers are included: "Preface" (Huey B. Long); "Self-Directed Learning: Smoke and Mirrors?" (Huey B. Long); "From Self-Culture to Self-Direction: An Historical Analysis of Self-Directed Learning" (Amy D. Rose); "The Link between Self-Directed and Transformative Learning" (Jane Pilling-Cormick);…

  11. Self-Directed Learning: Emerging Theory & Practice.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    This book contains the following collection of papers: "Self-Directed Learning: Emerging Theory and Practice" (Long); "Self-Directed Orientation toward Learning: A Learning Style" (Bonham); "Self-Direction and Problem Solving: Theory and Method" (Peters); "Facilitating Self-Directed Learning: Not a Contradiction…

  12. Self Directed Learning and Self Management. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on self-directed learning and self-management. "Validating a More-Dimensional Conception of Self-Directed Learning" (Gerald A. Straka, Cornelia Schaefer) discusses the development and validation of a conception of self-directed learning as a dynamic interplay between behavior,…

  13. Emerging Perspectives of Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    These 17 papers attest to the deepening and broadening interest in self-directed learning as one solution to the lifelong learning needs of men and women in an increasingly dynamic society. The papers include the following: "Self-Directed Learning Knowledge: Some Issues" (Long); "Development of Self-Directed Learning Readiness: A…

  14. Current Developments in Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    This document contains the following papers examining current developments in self-directed learning: "Self-Directed Learning: Challenges and Opportunities" (Huey B. Long); "Examination of Self-Directed Learning Readiness and Selected Demographic Variables of Top Female Executives" (Lucy M. Guglielmino); "Enhancing…

  15. New Ideas about Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    These 16 papers provide as complete a picture as possible of the current efforts in self-directed learning (SDL) application and research. The papers are: "Challenging Some Myths about Self-Directed Learning Research" (Long); "Childhood Experiences as Origins of Self-Directed Learning Experiences" (Long, Stubblefield);…

  16. Collective Calcium Signaling of Defective Multicellular Networks

    NASA Astrophysics Data System (ADS)

    Potter, Garrett; Sun, Bo

    2015-03-01

    A communicating multicellular network processes environmental cues into collective cellular dynamics. We have previously demonstrated that, when excited by extracellular ATP, fibroblast monolayers generate correlated calcium dynamics modulated by both the stimuli and gap junction communication between the cells. However, just as a well-connected neural network may be compromised by abnormal neurons, a tissue monolayer can also be defective with cancer cells, which typically have down regulated gap junctions. To understand the collective cellular dynamics in a defective multicellular network we have studied the calcium signaling of co-cultured breast cancer cells and fibroblast cells in various concentrations of ATP delivered through microfluidic devices. Our results demonstrate that cancer cells respond faster, generate singular spikes, and are more synchronous across all stimuli concentrations. Additionally, fibroblast cells exhibit persistent calcium oscillations that increase in regularity with greater stimuli. To interpret these results we quantitatively analyzed the immunostaining of purigenic receptors and gap junction channels. The results confirm our hypothesis that collective dynamics are mainly determined by the availability of gap junction communications.

  17. Intercellular mechanotransduction during multicellular morphodynamics

    PubMed Central

    Kim, Jin-Hong; Dooling, Lawrence J.; Asthagiri, Anand R.

    2010-01-01

    Multicellular structures are held together by cell adhesions. Forces that act upon these adhesions play an integral role in dynamically re-shaping multicellular structures during development and disease. Here, we describe different modes by which mechanical forces are transduced in a multicellular context: (i) indirect mechanosensing through compliant substratum, (ii) cytoskeletal ‘tug-of-war’ between cell–matrix and cell–cell adhesions, (iii) cortical contractility contributing to line tension, (iv) stresses associated with cell proliferation, and (v) forces mediating collective migration. These modes of mechanotransduction are recurring motifs as they play a key role in shaping multicellular structures in a wide range of biological contexts. Tissue morphodynamics may ultimately be understood as different spatio-temporal combinations of a select few multicellular transformations, which in turn are driven by these mechanotransduction motifs that operate at the bicellular to multicellular length scale. PMID:20356878

  18. Self-Directed Learning with Feedback

    ERIC Educational Resources Information Center

    Choi, Youngeun; Anderson, William

    2016-01-01

    This article describes a weekly writing assignment named SelFeed (Self-Directed Learning with Feedback), in which students are asked to identify their own questions relevant to the lecture content and provide logical answers.

  19. Moving Toward Self-directed Learning

    ERIC Educational Resources Information Center

    Jackson, Mae L.

    1973-01-01

    Independent learning and self direction is emphasized in an upper-grade classroom in Eugene, Oregon. The children take part in activities like spinning thread, role-playing, and constructing picture-story books for kindergarteners. (ST)

  20. Self-Directed Learning with Feedback

    ERIC Educational Resources Information Center

    Choi, Youngeun; Anderson, William

    2016-01-01

    This article describes a weekly writing assignment named SelFeed (Self-Directed Learning with Feedback), in which students are asked to identify their own questions relevant to the lecture content and provide logical answers.

  1. Biological soliton in multicellular movement

    NASA Astrophysics Data System (ADS)

    Kuwayama, Hidekazu; Ishida, Shuji

    2013-07-01

    Solitons have been observed in various physical phenomena. Here, we show that the distinct characteristics of solitons are present in the mass cell movement of non-chemotactic mutants of the cellular slime mould Dictyostelium discoideum. During starvation, D. discoideum forms multicellular structures that differentiate into spore or stalk cells and, eventually, a fruiting body. Non-chemotactic mutant cells do not form multicellular structures; however, they do undergo mass cell movement in the form of a pulsatile soliton-like structure (SLS). We also found that SLS induction is mediated by adhesive cell-cell interactions. These observations provide novel insights into the mechanisms of biological solitons in multicellular movement.

  2. Communication theory and multicellular biology.

    PubMed

    Mian, I S; Rose, C

    2011-04-01

    In this Perspective, we propose that communication theory--a field of mathematics concerned with the problems of signal transmission, reception and processing--provides a new quantitative lens for investigating multicellular biology, ancient and modern. What underpins the cohesive organisation and collective behaviour of multicellular ecosystems such as microbial colonies and communities (microbiomes) and multicellular organisms such as plants and animals, whether built of simple tissue layers (sponges) or of complex differentiated cells arranged in tissues and organs (members of the 35 or so phyla of the subkingdom Metazoa)? How do mammalian tissues and organs develop, maintain their architecture, become subverted in disease, and decline with age? How did single-celled organisms coalesce to produce many-celled forms that evolved and diversified into the varied multicellular organisms in existence today? Some answers can be found in the blueprints or recipes encoded in (epi)genomes, yet others lie in the generic physical properties of biological matter such as the ability of cell aggregates to attain a certain complexity in size, shape, and pattern. We suggest that Lasswell's maxim "Who says what to whom in what channel with what effect" provides a foundation for understanding not only the emergence and evolution of multicellularity, but also the assembly and sculpting of multicellular ecosystems and many-celled structures, whether of natural or human-engineered origin. We explore how the abstraction of communication theory as an organising principle for multicellular biology could be realised. We highlight the inherent ability of communication theory to be blind to molecular and/or genetic mechanisms. We describe selected applications that analyse the physics of communication and use energy efficiency as a central tenet. Whilst communication theory has and could contribute to understanding a myriad of problems in biology, investigations of multicellular biology

  3. The origins of multicellular organisms.

    PubMed

    Niklas, Karl J; Newman, Stuart A

    2013-01-01

    Multicellularity has evolved in several eukaryotic lineages leading to plants, fungi, and animals. Theoretically, in each case, this involved (1) cell-to-cell adhesion with an alignment-of-fitness among cells, (2) cell-to-cell communication, cooperation, and specialization with an export-of-fitness to a multicellular organism, and (3) in some cases, a transition from "simple" to "complex" multicellularity. When mapped onto a matrix of morphologies based on developmental and physical rules for plants, these three phases help to identify a "unicellular ⇒ colonial ⇒ filamentous (unbranched ⇒ branched) ⇒ pseudoparenchymatous ⇒ parenchymatous" morphological transformation series that is consistent with trends observed within each of the three major plant clades. In contrast, a more direct "unicellular ⇒ colonial or siphonous ⇒ parenchymatous" series is observed in fungal and animal lineages. In these contexts, we discuss the roles played by the cooptation, expansion, and subsequent diversification of ancestral genomic toolkits and patterning modules during the evolution of multicellularity. We conclude that the extent to which multicellularity is achieved using the same toolkits and modules (and thus the extent to which multicellularity is homologous among different organisms) differs among clades and even among some closely related lineages.

  4. Self-Directed Learning in Cultural Institutions.

    ERIC Educational Resources Information Center

    Carr, David

    1985-01-01

    Museums, libraries, zoos, parks, historical sites, and other cultural institutions can be vehicles for much self-directed learning. This article reviews these opportunities and efforts to utilize them. It discusses cultural institutions as invitational environments, conditions of learning in cultural institutions, and tools and initiatives for…

  5. Principal Development: Self-Directed Project Efficacy

    ERIC Educational Resources Information Center

    Piggot-Irvine, Eileen

    2011-01-01

    The inclusion of self-directed projects as an element within a New Zealand principal development programme was designed to reflect increasing support internationally for such a context-specific "inquiry" approach. The results reported in this article suggest that considerable clarity is required for such projects if they are to realize…

  6. Student Perspectives on Self-Directed Learning

    ERIC Educational Resources Information Center

    Douglass, Carolinda; Morris, Sherrill R.

    2014-01-01

    Undergraduate student perspectives regarding specific factors associated with self-directed learning were collected through eight focus groups. A total of 80 upperclassmen provided input revealing three emergent themes in the focus groups responses: (1) Student-Controlled, (2) Faculty-Controlled, and (3) Administration-Controlled Facilitators and…

  7. Self-Directed Thinking in the Curriculum.

    ERIC Educational Resources Information Center

    Dirkes, M. Ann

    1988-01-01

    Gifted students can learn to direct their thinking to maximize learning and creative production. They do this by stating what they intend to do, choosing strategies and appropriate conditions for thinking, and self-monitoring. The article describes techniques for developing self-directed thinking and applies these techniques to a class assignment.…

  8. Fostering Self-Directed Learners through Competitions

    ERIC Educational Resources Information Center

    Lafrenz, Lu Ann; Murray, Bernadine

    2005-01-01

    Educational programs are continually seeking ways to encourage students' independence, personal growth, and self-directed learning. Graduates should enter the fashion industry with the ability to engage in lifelong learning in order to ensure competence in professional practice. Competition experiences help students to achieve these goals. The…

  9. Learners' Perceptions of Self-Directed Study.

    ERIC Educational Resources Information Center

    Toebe, Dianne M.; And Others

    1982-01-01

    Alaska nurses who participated in self-directed continuing education courses were surveyed to determine what factors encouraged their participation. The strongest factors reported were personal satisfaction and need to update knowledge. Personal motivation and personal study habits appeared to be paramount in successful course completion. (SK)

  10. Principal Development: Self-Directed Project Efficacy

    ERIC Educational Resources Information Center

    Piggot-Irvine, Eileen

    2011-01-01

    The inclusion of self-directed projects as an element within a New Zealand principal development programme was designed to reflect increasing support internationally for such a context-specific "inquiry" approach. The results reported in this article suggest that considerable clarity is required for such projects if they are to realize…

  11. Cinegrams for Self-Directed Learning.

    ERIC Educational Resources Information Center

    Fischer, Detlev; Richards, Clive

    1995-01-01

    Presents potential uses of cinegrams for self-directed learning; shows how these interactive animated diagrams for technical documentation and training serve as browsing tools for the exploration of interrelated engine subsystems. Describes the development of a cinegram prototype implemented in HyperCard that shows the oil system of a Rolls Royce…

  12. Self-Directed Learning--Past and Present

    ERIC Educational Resources Information Center

    Roberson, Donald N., Jr.

    2005-01-01

    The purpose of this article is to present various findings on self-directed learning (SDL). The article contains three main parts: historical foundation of self-directed learning, a summary of various literature reviews on self-directed learning, and an analysis of current research on self-directed learning. SDL has been a significant factor in…

  13. Physician self-directed learning and education.

    PubMed

    Tagawa, Masami

    2008-07-01

    Physicians are expected to be life-long learners because updated and effective patient care should be provided while medical and clinical knowledge and skills and social requirements for patient care are rapidly changing. Also, qualified clinical competence needs long periods of training and each physician has to continually learn as long as he/she works as a professional. Self-directed learning is an important factor in adult learning. Medical students' readiness for self-directed learning is not high, and should be improved by medical school and postgraduate training curricula. Garrison proposed a comprehensive model of self-directed learning, and it has dimensions of motivation (entering and task), self-monitoring (responsibility), and self-management (responsibility). To teach individual self-directed learning competencies, the following are important: (1) situate learners to experience "real" problems; (2) encourage learners to reflect on their own performance; (3) create an educational atmosphere in clinical training situations. In 2005, a 2-year mandatory residency program was implemented in Japan, and fewer medical school graduates took residency programs in medical school hospitals and advanced specialty programs provided by medical school departments. Medical school departments provide traditional, but life-long clinical training opportunities. Under the new residency program, an additional postgraduate and continuing medical training system has to be built up to maintain and confirm a physician's competencies. If physicians do clinical work using a scholarly way of thinking with critical analysis of their own competencies and improvement by reflection, they will become an excellent life-long learner.

  14. On The Evolution of Bacterial Multicellularity

    PubMed Central

    Lyons, Nicholas A.; Kolter, Roberto

    2015-01-01

    Multicellularity is one of the most prevalent evolutionary innovations and nowhere is this more apparent than in the bacterial world, which contains many examples of multicellular organisms in a surprising array of forms. Due to their experimental accessibility and the large and diverse genomic data available, bacteria enable us to probe fundamental aspects of the origins of multicellularity. Here we discuss examples of multicellular behaviors in bacteria, the selective pressures that may have led to their evolution, possible origins and intermediate stages, and whether the ubiquity of apparently convergent multicellular forms argues for its inevitability. PMID:25597443

  15. Adult Participation in Self-Directed Learning Programs

    ERIC Educational Resources Information Center

    Abdullah, Muhammad Madi Bin; Koren, Sebastian Francis; Muniapan, Balakrishnan; Parasuraman, Balakrishnan; Rathakrishnan, Balan

    2008-01-01

    This paper attempts to explain the various concepts related to self-directed learning and also the various theories and models regarding adult participation and also non-participation in self-directed learning programs. Because of the extensive amount of previous literature and research findings dealing with self-directed learning, it is necessary…

  16. Conceptions of Self-Directed Learning: Theoretical and Conceptual Considerations. LOS, Learning Organized Self-Directed Researchgroup.

    ERIC Educational Resources Information Center

    Straka, Gerald A., Ed.

    This book consists of 15 papers addressing issues and conceptions of self-directed learning. The following are included: "Self-Directed Learning as a Political Idea" (Stephen D. Brookfield); "Social Influences on Individual Commitment to Self-Directed Learning at Work" (Alan J. Brown); "Goals of Self-Learning" (Rosemary S. Caffarella); "From…

  17. Advances in multicellular spheroids formation

    PubMed Central

    Cui, X.; Hartanto, Y.

    2017-01-01

    Three-dimensional multicellular spheroids (MCSs) have a complex architectural structure, dynamic cell–cell/cell–matrix interactions and bio-mimicking in vivo microenvironment. As a fundamental building block for tissue reconstruction, MCSs have emerged as a powerful tool to narrow down the gap between the in vitro and in vivo model. In this review paper, we discussed the structure and biology of MCSs and detailed fabricating methods. Among these methods, the approach in microfluidics with hydrogel support for MCS formation is promising because it allows essential cell–cell/cell–matrix interactions in a confined space. PMID:28202590

  18. Constraint Based Modeling Going Multicellular.

    PubMed

    Martins Conde, Patricia do Rosario; Sauter, Thomas; Pfau, Thomas

    2016-01-01

    Constraint based modeling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase the efficiency of microbial strains in chemical production pipelines. In addition, multiple models of multicellular organisms have been created including plants and humans. While initially the focus here was on modeling individual cell types of the multicellular organism, this focus recently started to switch. Models of microbial communities, as well as multi-tissue models of higher organisms have been constructed. These models thereby can include different parts of a plant, like root, stem, or different tissue types in the same organ. Such models can elucidate details of the interplay between symbiotic organisms, as well as the concerted efforts of multiple tissues and can be applied to analyse the effects of drugs or mutations on a more systemic level. In this review we give an overview of the recent development of multi-tissue models using constraint based techniques and the methods employed when investigating these models. We further highlight advances in combining constraint based models with dynamic and regulatory information and give an overview of these types of hybrid or multi-level approaches.

  19. Self-directed learning in health professions education.

    PubMed

    Murad, M Hassan; Varkey, Prathibha

    2008-07-01

    Self-directed learning has been recommended as a promising methodology for lifelong learning in medicine. However, the concept of self-directed learning continues to be elusive, with students and educators finding difficulty in defining it and agreeing on its worth. In this paper we review the literature of self-directed learning in health professions education and present a framework based on Malcolm Knowles' key components of self-directed learning. The key components of self-directed learning are: the educator as a facilitator, identification of learning needs, development of learning objectives, identification of appropriate resources, implementation of the process, commitment to a learning contract and evaluation of learning. Several but not all of these components are often described in the published literature. Although the presented framework provides some consistency for educators interested in applying SDL methods, future studies are needed to standardise self-directed learning curricula and to determine the effectiveness of these components on educational outcomes.

  20. The origin of multicellularity in cyanobacteria.

    PubMed

    Schirrmeister, Bettina E; Antonelli, Alexandre; Bagheri, Homayoun C

    2011-02-14

    Cyanobacteria are one of the oldest and morphologically most diverse prokaryotic phyla on our planet. The early development of an oxygen-containing atmosphere approximately 2.45-2.22 billion years ago is attributed to the photosynthetic activity of cyanobacteria. Furthermore, they are one of the few prokaryotic phyla where multicellularity has evolved. Understanding when and how multicellularity evolved in these ancient organisms would provide fundamental information on the early history of life and further our knowledge of complex life forms. We conducted and compared phylogenetic analyses of 16S rDNA sequences from a large sample of taxa representing the morphological and genetic diversity of cyanobacteria. We reconstructed ancestral character states on 10,000 phylogenetic trees. The results suggest that the majority of extant cyanobacteria descend from multicellular ancestors. Reversals to unicellularity occurred at least 5 times. Multicellularity was established again at least once within a single-celled clade. Comparison to the fossil record supports an early origin of multicellularity, possibly as early as the "Great Oxygenation Event" that occurred 2.45-2.22 billion years ago. The results indicate that a multicellular morphotype evolved early in the cyanobacterial lineage and was regained at least once after a previous loss. Most of the morphological diversity exhibited in cyanobacteria today--including the majority of single-celled species--arose from ancient multicellular lineages. Multicellularity could have conferred a considerable advantage for exploring new niches and hence facilitated the diversification of new lineages.

  1. The origin of multicellularity in cyanobacteria

    PubMed Central

    2011-01-01

    Background Cyanobacteria are one of the oldest and morphologically most diverse prokaryotic phyla on our planet. The early development of an oxygen-containing atmosphere approximately 2.45 - 2.22 billion years ago is attributed to the photosynthetic activity of cyanobacteria. Furthermore, they are one of the few prokaryotic phyla where multicellularity has evolved. Understanding when and how multicellularity evolved in these ancient organisms would provide fundamental information on the early history of life and further our knowledge of complex life forms. Results We conducted and compared phylogenetic analyses of 16S rDNA sequences from a large sample of taxa representing the morphological and genetic diversity of cyanobacteria. We reconstructed ancestral character states on 10,000 phylogenetic trees. The results suggest that the majority of extant cyanobacteria descend from multicellular ancestors. Reversals to unicellularity occurred at least 5 times. Multicellularity was established again at least once within a single-celled clade. Comparison to the fossil record supports an early origin of multicellularity, possibly as early as the "Great Oxygenation Event" that occurred 2.45 - 2.22 billion years ago. Conclusions The results indicate that a multicellular morphotype evolved early in the cyanobacterial lineage and was regained at least once after a previous loss. Most of the morphological diversity exhibited in cyanobacteria today —including the majority of single-celled species— arose from ancient multicellular lineages. Multicellularity could have conferred a considerable advantage for exploring new niches and hence facilitated the diversification of new lineages. PMID:21320320

  2. Antimicrobial peptides of multicellular organisms

    NASA Astrophysics Data System (ADS)

    Zasloff, Michael

    2002-01-01

    Multicellular organisms live, by and large, harmoniously with microbes. The cornea of the eye of an animal is almost always free of signs of infection. The insect flourishes without lymphocytes or antibodies. A plant seed germinates successfully in the midst of soil microbes. How is this accomplished? Both animals and plants possess potent, broad-spectrum antimicrobial peptides, which they use to fend off a wide range of microbes, including bacteria, fungi, viruses and protozoa. What sorts of molecules are they? How are they employed by animals in their defence? As our need for new antibiotics becomes more pressing, could we design anti-infective drugs based on the design principles these molecules teach us?

  3. The Multiple Origins of Complex Multicellularity

    NASA Astrophysics Data System (ADS)

    Knoll, Andrew H.

    2011-05-01

    Simple multicellularity has evolved numerous times within the Eukarya, but complex multicellular organisms belong to only six clades: animals, embryophytic land plants, florideophyte red algae, laminarialean brown algae, and two groups of fungi. Phylogeny and genomics suggest a generalized trajectory for the evolution of complex multicellularity, beginning with the co-optation of existing genes for adhesion. Molecular channels to facilitate cell-cell transfer of nutrients and signaling molecules appear to be critical, as this trait occurs in all complex multicellular organisms but few others. Proliferation of gene families for transcription factors and cell signals accompany the key functional innovation of complex multicellular clades: differentiated cells and tissues for the bulk transport of oxygen, nutrients, and molecular signals that enable organisms to circumvent the physical limitations of diffusion. The fossil records of animals and plants document key stages of this trajectory.

  4. The multicellularity genes of dictyostelid social amoebas

    PubMed Central

    Glöckner, Gernot; Lawal, Hajara M.; Felder, Marius; Singh, Reema; Singer, Gail; Weijer, Cornelis J.; Schaap, Pauline

    2016-01-01

    The evolution of multicellularity enabled specialization of cells, but required novel signalling mechanisms for regulating cell differentiation. Early multicellular organisms are mostly extinct and the origins of these mechanisms are unknown. Here using comparative genome and transcriptome analysis across eight uni- and multicellular amoebozoan genomes, we find that 80% of proteins essential for the development of multicellular Dictyostelia are already present in their unicellular relatives. This set is enriched in cytosolic and nuclear proteins, and protein kinases. The remaining 20%, unique to Dictyostelia, mostly consists of extracellularly exposed and secreted proteins, with roles in sensing and recognition, while several genes for synthesis of signals that induce cell-type specialization were acquired by lateral gene transfer. Across Dictyostelia, changes in gene expression correspond more strongly with phenotypic innovation than changes in protein functional domains. We conclude that the transition to multicellularity required novel signals and sensors rather than novel signal processing mechanisms. PMID:27357338

  5. Multicellularity makes somatic differentiation evolutionarily stable

    PubMed Central

    Wahl, Mary E.; Murray, Andrew W.

    2016-01-01

    Many multicellular organisms produce two cell lineages: germ cells, whose descendants produce the next generation, and somatic cells, which support, protect, and disperse the germ cells. This germ-soma demarcation has evolved independently in dozens of multicellular taxa but is absent in unicellular species. A common explanation holds that in these organisms, inefficient intercellular nutrient exchange compels the fitness cost of producing nonreproductive somatic cells to outweigh any potential benefits. We propose instead that the absence of unicellular, soma-producing populations reflects their susceptibility to invasion by nondifferentiating mutants that ultimately eradicate the soma-producing lineage. We argue that multicellularity can prevent the victory of such mutants by giving germ cells preferential access to the benefits conferred by somatic cells. The absence of natural unicellular, soma-producing species previously prevented these hypotheses from being directly tested in vivo: to overcome this obstacle, we engineered strains of the budding yeast Saccharomyces cerevisiae that differ only in the presence or absence of multicellularity and somatic differentiation, permitting direct comparisons between organisms with different lifestyles. Our strains implement the essential features of irreversible conversion from germ line to soma, reproductive division of labor, and clonal multicellularity while maintaining sufficient generality to permit broad extension of our conclusions. Our somatic cells can provide fitness benefits that exceed the reproductive costs of their production, even in unicellular strains. We find that nondifferentiating mutants overtake unicellular populations but are outcompeted by multicellular, soma-producing strains, suggesting that multicellularity confers evolutionary stability to somatic differentiation. PMID:27402737

  6. Development of the Self-Directed Learning Skills Scale

    ERIC Educational Resources Information Center

    Ayyildiz, Yildizay; Tarhan, Leman

    2015-01-01

    The purpose of this study was to develop a valid and reliable scale for assessing high school students' self-directed learning skills. Based on a literature review and data obtained from similar instruments, all skills related to self-directed learning were identified. Next, an item pool was prepared and administered to 255 students from various…

  7. Interactive Multimedia Instruction for Training Self-Directed Learning Techniques

    DTIC Science & Technology

    2016-06-01

    1 Research Product 2016-056 Interactive Multimedia Instruction for Training Self-Directed Learning Techniques Paul N...December 2014 4. TITLE AND SUBTITLE Interactive Multimedia Instruction for Training Self-Directed Learning Techniques 5a. CONTRACT OR GRANT...DTIC as ARI Research Product 2016-05. 15. SUBJECT TERMS Army Learning Model, Army Learning Concept 2015, Interactive Multimedia

  8. Founders' Continuing Roles in Schools Supporting Self-Directed Learning

    ERIC Educational Resources Information Center

    Nash, Carol

    2014-01-01

    What should be the continuing role of founders in schools supporting self-directed learning? To answer this, the founders' views of two North American schools for self-directed learners will be compared. One school is exam-focused and private; the other is, test-free and public. The founders of both schools have comparable beliefs regarding the…

  9. Views of Gifted Elementary Students about Self-Directed Learning

    ERIC Educational Resources Information Center

    Van Deur, Penny

    2011-01-01

    Despite the connection between independent learning and gifted students, little is known of the views these students hold about the process of being self-directed learners. This interview study examined views of ten gifted elementary school students in South Australia about Self-Directed Learning. The interview responses showed that these gifted…

  10. A Study of Barriers to Adult Self-Directed Learning

    ERIC Educational Resources Information Center

    Douglas, Edward

    2010-01-01

    Self-directed learning has contributed significantly to adult learners' personal and professional growth. Approximately 70% of adult learning is through a self-directed learning context (Heimstra, 2008). This quantitative correlational study involved an attempt to determine the nature of the relationship between situational, dispositional, and…

  11. Development of the Self-Directed Learning Skills Scale

    ERIC Educational Resources Information Center

    Ayyildiz, Yildizay; Tarhan, Leman

    2015-01-01

    The purpose of this study was to develop a valid and reliable scale for assessing high school students' self-directed learning skills. Based on a literature review and data obtained from similar instruments, all skills related to self-directed learning were identified. Next, an item pool was prepared and administered to 255 students from various…

  12. Modeling Spaces for Self-Directed Learning at University Courses

    ERIC Educational Resources Information Center

    Pata, Kai

    2009-01-01

    This paper conceptualizes the theoretical framework of modeling learning spaces for self-directed learning at university courses. It binds together two ideas: (a) self-directed learners' common learning spaces may be characterized as abstract niches, (b) niche characteristics are collectively determined through individually perceived affordances.…

  13. Advances in Research and Practice in Self-Directed Learning.

    ERIC Educational Resources Information Center

    Long, Huey B.; And Others

    Selected papers presented in this book are: "Changing Concepts of Self-Direction in Learning" (Long); "The Transition from Learner-Control to Autodidaxy: More than Meets the Eye" (Candy); "Self-Directed Learning and the Theory of Adult Education" (Jarvis); "On the Theme and Variations of Self-Directed…

  14. 42 CFR 441.452 - Self-direction: General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Self-direction: General. 441.452 Section 441.452 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... must have in place, before electing the self-directed PAS option, personal care services through the...

  15. Modeling Spaces for Self-Directed Learning at University Courses

    ERIC Educational Resources Information Center

    Pata, Kai

    2009-01-01

    This paper conceptualizes the theoretical framework of modeling learning spaces for self-directed learning at university courses. It binds together two ideas: (a) self-directed learners' common learning spaces may be characterized as abstract niches, (b) niche characteristics are collectively determined through individually perceived affordances.…

  16. Processes of Change in Self-Directed Couple Relationship Education

    ERIC Educational Resources Information Center

    Wilson, Keithia L.; Halford, W. Kim

    2008-01-01

    The current study examined the learning processes involved in professionally supported self-directed couple relationship education (CRE). Fifty-nine couples completed Couple CARE, a systematic, self-directed CRE program designed in flexible delivery mode to be completed at home. Couples watched a DVD introducing key relationship ideas and skills…

  17. Self-Directed Learning Readiness at General Motors Japan.

    ERIC Educational Resources Information Center

    Beitler, Michael A.

    Although self-directed learning (SDL) has been promoted by businesses as being needed by managers, traditional business schools have not promoted this type of learning. In addition, some adult learners are not ready for SDL, and some subjects (such as accounting) are not suitable for SDL. The concept of self-directed learning readiness (SDLR) can…

  18. Founders' Continuing Roles in Schools Supporting Self-Directed Learning

    ERIC Educational Resources Information Center

    Nash, Carol

    2014-01-01

    What should be the continuing role of founders in schools supporting self-directed learning? To answer this, the founders' views of two North American schools for self-directed learners will be compared. One school is exam-focused and private; the other is, test-free and public. The founders of both schools have comparable beliefs regarding the…

  19. Professional Development Planning: A Self-Directed Approach.

    ERIC Educational Resources Information Center

    Lamble, Wayne

    1983-01-01

    Presents an overview of a self-directed approach to professional development. Describes the major components as self-assessment of professional strengths and learning needs, planning, and organizing activities and records for professional development. Gives reasons for, benefits from, and requirements of a self-directed approach. (Availability:…

  20. Bacterial Ventures into Multicellularity: Collectivism through Individuality.

    PubMed

    van Vliet, Simon; Ackermann, Martin

    2015-06-01

    Multicellular eukaryotes can perform functions that exceed the possibilities of an individual cell. These functions emerge through interactions between differentiated cells that are precisely arranged in space. Bacteria also form multicellular collectives that consist of differentiated but genetically identical cells. How does the functionality of these collectives depend on the spatial arrangement of the differentiated bacteria? In a previous issue of PLOS Biology, van Gestel and colleagues reported an elegant example of how the spatial arrangement of differentiated cells gives rise to collective behavior in Bacillus subtilus colonies, further demonstrating the similarity of bacterial collectives to higher multicellular organisms.

  1. Myxobacteria, Polarity, and Multicellular Morphogenesis

    PubMed Central

    Kaiser, Dale; Robinson, Mark; Kroos, Lee

    2010-01-01

    Myxobacteria are renowned for the ability to sporulate within fruiting bodies whose shapes are species-specific. The capacity to build those multicellular structures arises from the ability of M. xanthus to organize high cell-density swarms, in which the cells tend to be aligned with each other while constantly in motion. The intrinsic polarity of rod-shaped cells lays the foundation, and each cell uses two polar engines for gliding on surfaces. It sprouts retractile type IV pili from the leading cell pole and secretes capsular polysaccharide through nozzles from the trailing pole. Regularly periodic reversal of the gliding direction was found to be required for swarming. Those reversals are generated by a G-protein switch which is driven by a sharply tuned oscillator. Starvation induces fruiting body development, and systematic reductions in the reversal frequency are necessary for the cells to aggregate rather than continue to swarm. Developmental gene expression is regulated by a network that is connected to the suppression of reversals. PMID:20610548

  2. The Evolution of Multicellular Plants and Animals.

    ERIC Educational Resources Information Center

    Valentine, James W.

    1978-01-01

    Traces the evolution of unicellular organisms to the multi-cellular plants and animals in existence today. Major events are depicted in a geologic timetable. Organisms, extinct and recent, are classified by taxonomic group. (MA)

  3. The Evolution of Multicellular Plants and Animals.

    ERIC Educational Resources Information Center

    Valentine, James W.

    1978-01-01

    Traces the evolution of unicellular organisms to the multi-cellular plants and animals in existence today. Major events are depicted in a geologic timetable. Organisms, extinct and recent, are classified by taxonomic group. (MA)

  4. The simplest integrated multicellular organism unveiled.

    PubMed

    Arakaki, Yoko; Kawai-Toyooka, Hiroko; Hamamura, Yuki; Higashiyama, Tetsuya; Noga, Akira; Hirono, Masafumi; Olson, Bradley J S C; Nozaki, Hisayoshi

    2013-01-01

    Volvocine green algae represent the "evolutionary time machine" model lineage for studying multicellularity, because they encompass the whole range of evolutionary transition of multicellularity from unicellular Chlamydomonas to >500-celled Volvox. Multicellular volvocalean species including Gonium pectorale and Volvox carteri generally have several common morphological features to survive as integrated multicellular organisms such as "rotational asymmetry of cells" so that the cells become components of the individual and "cytoplasmic bridges between protoplasts in developing embryos" to maintain the species-specific form of the multicellular individual before secretion of new extracellular matrix (ECM). However, these morphological features have not been studied in the four-celled colonial volvocine species Tetrabaena socialis that is positioned in the most basal lineage within the colonial or multicellular volvocine greens. Here we established synchronous cultures of T. socialis and carried out immunofluorescence microscopic and ultrastructural observations to elucidate these two morphological attributes. Based on immunofluorescence microscopy, four cells of the mature T. socialis colony were identical in morphology but had rotational asymmetry in arrangement of microtubular rootlets and separation of basal bodies like G. pectorale and V. carteri. Ultrastructural observations clearly confirmed the presence of cytoplasmic bridges between protoplasts in developing embryos of T. socialis even after the formation of new flagella in each daughter protoplast within the parental ECM. Therefore, these two morphological attributes might have evolved in the common four-celled ancestor of the colonial volvocine algae and contributed to the further increase in cell number and complexity of the multicellular individuals of this model lineage. T. socialis is one of the simplest integrated multicellular organisms in which four identical cells constitute the individual.

  5. Iranian Clinical Nurses’ Readiness for Self-Directed Learning

    PubMed Central

    Malekian, Morteza; Ghiyasvandian, Sharzad; Cheraghi, Mohammad Ali; Hassanzadeh, Akbar

    2016-01-01

    Introduction: Clinical nurses are in need of being able to adapt to the ever-changing environment of clinical settings. The prerequisite for their successful adaptation is to be lifelong learners. An approach for making nurses lifelong learners is self-directed learning. Aims: This study was undertaken to evaluate a group of Iranian clinical nurses’ readiness for self-directed learning and its relationship with some of their personal characteristics. Methods: This cross-sectional descriptive study was conducted in 2014. A random sample of 314 nurses working in three hospitals affiliated to Isfahan Social Security Organization, Isfahan, Iran, was recruited to complete the Fisher’s Self-directed Learning Readiness Scale. Findings: In total, 279 nurses filled the scale completely. The mean of their readiness for self-directed learning was 162.50±14.11 (120–196). The correlation of self-directed learning readiness with age, gender, marital status, and university degree was not statistically significant. Conclusion: Most nurses had great readiness for self-directed learning. Accordingly, nursing policy-makers need to develop strategies for promoting their self-directed learning. Moreover, innovative teaching methods such as problem solving and problem-based learning should be employed to prepare nurses for effectively managing the complexities of their ever-changing work environment. PMID:26234971

  6. Self-directed work teams in marketing organizations.

    PubMed

    Gilbertson, T F

    1999-01-01

    As marketing organizations move toward the 21st century they are becoming concerned with the development of self-directed work teams. Marketing organizations that have informed, motivated, skilled, trained, and committed employees will out perform organizations which operate in the traditional manner. Many self-directed work teams have grown out of the quality circles. The goal of these teams is to increase employee involvement in decisions of the organization to the greatest extent that employees' knowledge and training allow. In fact, today's marketing organizations need to be able to respond quickly to change driven by internal and external customers. The winning organizations will be able to produce more product with better quality in less time by staying lean, flexible, and implementing self-directed work teams. Marketing organizations that can commit to self-directed work teams will benefit by having customer and employee satisfaction, money saved, and excessive bureaucracy eliminated.

  7. Making Choices: Self-Directed Teams or Total Quality Management?

    ERIC Educational Resources Information Center

    Holpp, Lawrence

    1992-01-01

    Describes differences between total quality management and self-directed teams in terms of job design, decision making, flexibility, supervision, labor relations, quality, customers, and training. Offers suggestions for which method to choose when. (SK)

  8. Beyond the classroom: self-direction in professional learning.

    PubMed

    Mayfield, M K

    1993-10-01

    Against the backdrop of a rapidly changing profession, the context for professional thinking among medical librarians is changing. Competent performance increasingly is linked with the educational efforts of self-directed adult learners. This paper examines strategies that facilitate self-direction, including skills development, organizational learning, learner-based decision making, and alternative teaching models. The analysis provides the basis for a recommended agenda for redesign and development of educational programs.

  9. Beyond the classroom: self-direction in professional learning.

    PubMed Central

    Mayfield, M K

    1993-01-01

    Against the backdrop of a rapidly changing profession, the context for professional thinking among medical librarians is changing. Competent performance increasingly is linked with the educational efforts of self-directed adult learners. This paper examines strategies that facilitate self-direction, including skills development, organizational learning, learner-based decision making, and alternative teaching models. The analysis provides the basis for a recommended agenda for redesign and development of educational programs. PMID:8251979

  10. Self-directed versus traditional classroom training for neonatal resuscitation.

    PubMed

    Weiner, Gary M; Menghini, Karin; Zaichkin, Jeanette; Caid, Ann E; Jacoby, Carrie J; Simon, Wendy M

    2011-04-01

    Neonatal Resuscitation Program instructors spend most of their classroom time giving lectures and demonstrating basic skills. We hypothesized that a self-directed education program could shift acquisition of these skills outside the classroom, shorten the duration of the class, and allow instructors to use their time to facilitate low-fidelity simulation and debriefing. Novice providers were randomly allocated to self-directed education or a traditional class. Self-directed participants received a textbook, instructional video, and portable equipment kit and attended a 90-minute simulation session with an instructor. The traditional class included 6 hours of lectures and instructor-directed skill stations. Outcome measures included resuscitation skill (megacode assessment score), content knowledge, participant satisfaction, and self-confidence. Forty-six subjects completed the study. There was no significant difference between the study groups in either the megacode assessment score (23.8 [traditional] vs 24.5 [self-directed]; P = .46) or fraction that passed the "megacode" (final skills assessment) (56% [traditional] vs 65% [self-directed]; P = .76). There were no significant differences in content knowledge, course satisfaction, or postcourse self-confidence. Content knowledge, years of experience, and self-confidence did not predict resuscitation skill. Self-directed education improves the educational efficiency of the neonatal resuscitation course by shifting the acquisition of cognitive and basic procedural skills outside of the classroom, which allows the instructor to add low-fidelity simulation and debriefing while significantly decreasing the duration of the course.

  11. Self-directed practice schedule enhances learning of suturing skills.

    PubMed

    Safir, Oleg; Williams, Camille K; Dubrowski, Adam; Backstein, David; Carnahan, Heather

    2013-12-01

    Most preoperative surgical training programs experience challenges with the availability of expert surgeons to teach trainees. Some research suggests that trainees may benefit from being allowed to actively shape their learning environments, which could alleviate some of the time and resource pressures in surgical training. The purpose of this study was to investigate the effects of self-directed or prescribed practice schedules (random or blocked) on learning suturing skills. Participants watched an instructional video for simple interrupted, vertical mattress and horizontal mattress suturing then completed a pretest to assess baseline skills. Participants were assigned to 1 of 4 practice groups: self-directed practice schedule, prescribed blocked practice schedule, prescribed random practice schedule or matched to the self-directed group (control). Practice of the skill was followed by a delayed (1 h) posttest. Improvement from pretest to posttest was determined based on differences in performance time and expert-based assessments. Analyses revealed a significant effect of group for difference in performance time of the simple interrupted suture. Random practice did not show the expected advantage for skill learning, but there was an advantage of self-directed practice. Self-directed practice schedules may be desirable for optimal learning of simple technical skills, even when expert instruction is available. Instructors must also take into account the interaction between task difficulty and conditions of practice to develop ideal training environments.

  12. Bacterial biofilms: prokaryotic adventures in multicellularity.

    PubMed

    Webb, Jeremy S; Givskov, Michael; Kjelleberg, Staffan

    2003-12-01

    The development of bacterial biofilms includes both the initial social behavior of undifferentiated cells, as well as cell death and differentiation in the mature biofilm, and displays several striking similarities with higher organisms. Recent advances in the field provide new insight into differentiation and cell death events in bacterial biofilm development and propose that biofilms have an unexpected level of multicellularity.

  13. Limits to Chemically Guided Multicellular Migration

    NASA Astrophysics Data System (ADS)

    Varennes, Julien; Han, Bumsoo; Mugler, Andrew

    Collective cell migration in response to a chemical cue requires both multicellular sensing of chemical gradients and coordinated mechanical action. Examples from morphogenesis and cancer metastasis demonstrate that clusters of migratory cells are extremely sensitive, responding to gradients of less than 1% difference in chemical concentration across a cell body. While the limits to multicellular sensing are becoming known, the ensuing consequences for coherent migration remain poorly understood. We develop a model of multicellular sensing and migration based on the cellular Potts model. Multicellular sensing of noisy chemical gradients is modeled as a process of local excitation and global inhibition (LEGI) among communicating cells. The output of the sensing process is coupled to individual cells' polarization to model migratory behavior. We find that larger clusters of cells detect the gradient direction with higher precision and thus achieve stronger polarization bias. At the same time, larger clusters are also accompanied by less coherent collective motion. The trade-off between these two effects leads to an optimally efficient cluster size. We discuss how our results relate to cancer metastasis.

  14. Conference on multicellular and interactive behavior of bacteria

    SciTech Connect

    Not Available

    1994-11-01

    This document provides abstracts for oral presentations at an American Society of Microbiology Conference on Multicellular and interactive behavior of bacteria. Sessions included: Cell to Cell interactions and exchange of genetic material; symbiotic interactions; multicellular aspects of pathogenesis; multicellular motility; developmental interactions; metabolic interactions; interactions in biofilms and surface colonization; pattern formation and colonial interactions.

  15. Self-Directed Lifelong Learning in Hybrid Learning Configurations

    ERIC Educational Resources Information Center

    Cremers, Petra H. M.; Wals, Arjen E. J.; Wesselink, Renate; Nieveen, Nienke; Mulder, Martin

    2014-01-01

    Present-day students are expected to be lifelong learners throughout their working life. Higher education must therefore prepare students to self-direct their learning beyond formal education, in real-life working settings. This can be achieved in so-called hybrid learning configurations in which working and learning are integrated. In such a…

  16. Enhancing Self-Directed Behavior in the Classroom.

    ERIC Educational Resources Information Center

    Heuchert, Charles M.

    1989-01-01

    Students can develop self-directed behavior when behavior management strategies are structured to provide opportunities to learn responsible behavior, make choices, and develop internal control. Student behavior is viewed as a response to psychological needs for love and belonging, power, freedom, and fun. Components of a reality therapy session…

  17. Self-Directed Support Policy: Challenges and Possible Solutions

    ERIC Educational Resources Information Center

    Harkes, Mary A.; Brown, Michael; Horsburgh, Dorothy

    2014-01-01

    A systematic literature review was conducted between September 2010 and April 2011 and published earlier in this journal, paper 1. The findings indicated that few studies of Self-Directed Support focused specifically on people with intellectual disabilities. The range of individuals' ability and distinction between adults with or without…

  18. Increasing self-directed training in neurorehabilitation patients through competition.

    PubMed

    Studer, B; Van Dijk, H; Handermann, R; Knecht, S

    2016-01-01

    This proof-of-concept study aimed to test whether competition could be a useful tool to increase intensity and amount of self-directed training in neurorehabilitation. Stroke patients undergoing inpatient neurorehabilitation (n=93) conducted self-directed endurance training on a (wheelchair-compatible) bicycle trainer under three experimental conditions: a "Competition" condition and two noncompetition control conditions (repeated randomized within-subject design). Training performance and perceived exertion were recorded and statistically analyzed. Three motivational effects of competition were found. First, competition led to an increase in self-directed training. Patients exercised significantly more intensively under competition than in the two noncompetition control conditions. Second, (winning a) competition had a positive influence on performance in the subsequent training session. Third, training performance was particularly high during rematch competitions; that is to say, during second encounter competitions against an opponent that the patient had just beaten. No systematic effect of competition upon perceived exertion (controlled for training performance) was found. Together, our results demonstrate that competition is a potent motivational tool to increase self-directed training in neurorehabilitation. © 2016 Elsevier B.V. All rights reserved.

  19. Analysis of Self-Directed Mastery Learning of Honors Physics

    ERIC Educational Resources Information Center

    Athens, Wendy

    2011-01-01

    Self-directed learning (SDL) is an important life skill in a knowledge-based society and prepares students to persist, manage their time and resources, use logic to construct their knowledge, argue their views, and collaborate. The purpose of this study was to facilitate mastery of physics concepts through self-directedness in formative testing…

  20. Promoting Self-Directed Revision in EFL Writing Classes

    ERIC Educational Resources Information Center

    Coomber, Matthew

    2016-01-01

    Second language writers need to develop the ability to revise their writing independently of third party advice; thus, it is important that teachers devise methods by which to promote habits of self-directed revision. This quasi-experimental study investigates three classroom activities designed to encourage students to independently revise essays…

  1. The Educational Affordances of Blogs for Self-Directed Learning

    ERIC Educational Resources Information Center

    Robertson, Judy

    2011-01-01

    To be successful university learners, students need to develop skills in self-directed learning. This encompasses a range of cognitive and meta-cognitive skills including generating one's own learning goals, planning how to tackle a problem, evaluating whether learning goals have been met, and re-planning based on this evaluation. The educational…

  2. Self-Directed Learning Dissertation Abstracts 1966-1991.

    ERIC Educational Resources Information Center

    Long, Huey B.; Redding, Terrence R.

    This index contains abstracts of 173 doctoral dissertations about the following aspects of adult self-directed learning: program areas of adult education (AE); instructional methods/techniques; institutional sponsors of AE; personnel and staffing in AE; education of particular clientele groups; processes of program planning and administration;…

  3. Self-Direction in On-Line Language Learning

    ERIC Educational Resources Information Center

    Rappel, L.

    2017-01-01

    This paper presents design based research on the role of self-direction in online learning by exploring elements of both individual and collective engagement as significant aspects of learning. By making the claim that online instruction draws on autonomous and social aspects of learning, this paper examines how online teaching environments are…

  4. Self-Directed Learning: A Tool for Lifelong Learning

    ERIC Educational Resources Information Center

    Boyer, Stefanie L.; Edmondson, Diane R.; Artis, Andrew B.; Fleming, David

    2014-01-01

    A meta-analytic review of self-directed learning (SDL) research over 30 years, five countries, and across multiple academic disciplines is used to explore its relationships with five key nomologically related constructs for effective workplace learning. The meta-analysis revealed positive relationships between SDL and internal locus of control,…

  5. Towards an Etiological Model of Self-Directed Professional Development.

    ERIC Educational Resources Information Center

    Bouchard, Paul

    The role that individual learning proficiency, individual personality characteristics, and chance occurrences in the learner's environment play in self-directed professional development was examined through semistructured interviews with a purposeful sample of eight professional men and women of high achievement with no postsecondary schooling in…

  6. Self-Directed Learning in Adulthood: A Literature Review.

    ERIC Educational Resources Information Center

    Owen, T. Ross

    Self-directed learning (SDL) is among the most productive areas of research in adult education. Malcolm S. Knowles is credited with a comprehensive synthesis of adult teaching and adult learning principles. Andragogy, the art and science of helping adults learn, lies at the heart of Knowles' work. Lucy M. Guglielmino theorized regarding the…

  7. Portfolio: A Tool for Self-Directed Learning at Work.

    ERIC Educational Resources Information Center

    Lyons, Nona; Evans, Linda

    The Portfolio Project was conducted to promote lifelong, self-directed learning in the workplace. The project, which offered courses on basic skills, supervisory communications, and English as a second language, was initiated as a literacy demonstration project by the Casco Bay Partnership (CBP), which brought together government, educators, and…

  8. 42 CFR 441.452 - Self-direction: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... both traditional service delivery and the self-directed PAS service delivery option available in the... PAS service delivery option. (c) The State's assessment of an individual's needs must form the basis... Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN...

  9. Developing Student Competence in Self-Directed IEPs

    ERIC Educational Resources Information Center

    Torgerson, C. W.; Miner, C. A.; Shen, H.

    2004-01-01

    Self-directed Individualized Education Programs (IEPs) allow students to assume leadership and become actively involved in the decisions made at their IEP meetings. This article describes how through direct instruction, social skills discussion, active practice, and role-playing students are prepared to facilitate their meeting. This active…

  10. Personal Learning Environments: A Solution for Self-Directed Learners

    ERIC Educational Resources Information Center

    Haworth, Ryan

    2016-01-01

    In this paper I discuss "personal learning environments" and their diverse benefits, uses, and implications for life-long learning. Personal Learning Environments (PLEs) are Web 2.0 and social media technologies that enable individual learners the ability to manage their own learning. Self-directed learning is explored as a foundation…

  11. Self-Directed Learning. Myths and Realities No. 3.

    ERIC Educational Resources Information Center

    Kerka, Sandra

    In one school of thought, self-directed learning (SDL) is based in the autonomous, independent individual who chooses to undertake learning for personal growth. However, another school of thought stresses the social construction of knowledge and the social context of learning. Some writers challenge the exclusive emphasis on the autonomous self…

  12. Self-Directed Informal Learning: A Case Study

    ERIC Educational Resources Information Center

    Hanstock, Robyn

    2004-01-01

    This case study examines the life journey of a self-directed adult learner who has made remarkable achievements in overcoming a difficult educational beginning in early childhood, as well as personal trauma in adulthood. The subject has shown determination in seeking out his own opportunities to learn in spite of major drawbacks, chief of which…

  13. A Study of Self-Directed Professionals of High Attainment.

    ERIC Educational Resources Information Center

    Bouchard, Paul

    The determinants of self-directed learning (SDL) among professionals of high attainment were examined through open-ended, semidirected interviews with a purposeful sample of eight professional men and women who have acquired identifiable, high-level professional knowledge/skills typically taught in postsecondary learning institutions without ever…

  14. Vocational Interests (The Self-Directed Search) of Female Carpenters

    ERIC Educational Resources Information Center

    Swan, Kathy C.

    2005-01-01

    In this national sample of female carpenters (N=411) who began their apprenticeship with the United Brotherhood of Carpenters during the 1990s in the United States, the author provides a profile of female carpenters' vocational interests (The Self-Directed Search). The vocational interests of 137 male carpenters also were gathered for comparison.…

  15. Implementing Self-Directed Work Teams at a College Newspaper

    ERIC Educational Resources Information Center

    de Pillis, Emmeline; Parsons, Blake

    2013-01-01

    The problem: Motivating and retaining staff had become an ongoing problem at the student newspaper. Student staffers would quit abruptly when overwhelmed or dissatisfied, leaving the newspaper with critical positions vacant. This affected the performance of the newspaper. Method: The newspaper was organized into self directed work teams (SDWTs).…

  16. Differential Client Satisfaction with Holland's Self-Directed Search.

    ERIC Educational Resources Information Center

    Byrne, Thomas P.; And Others

    1979-01-01

    Satisfaction with Holland's Self-Directed Search (SDS) was measured using a sample of college freshmen, dichotomized on Rotter's construct of locus of control and Holland's construct of differentiation. Results support the prediction that internally controlled individuals would be more satisfied with the SDS than externally controlled students.…

  17. Enhancing Self-Directed Behavior in the Classroom.

    ERIC Educational Resources Information Center

    Heuchert, Charles M.

    1989-01-01

    Students can develop self-directed behavior when behavior management strategies are structured to provide opportunities to learn responsible behavior, make choices, and develop internal control. Student behavior is viewed as a response to psychological needs for love and belonging, power, freedom, and fun. Components of a reality therapy session…

  18. Competencies Acquisition through Self-Directed Learning among Malaysian Managers

    ERIC Educational Resources Information Center

    Hashim, Junaidah

    2008-01-01

    Purpose: The purpose of this paper is to examine how Malaysian managers acquire job competencies through self-directed learning activities at their workplace. Specifically it aims to investigate what types of job competencies are required for the managers, how they learn to acquire those competencies, and whether the managers have the…

  19. Implementing Self-Directed Work Teams at a College Newspaper

    ERIC Educational Resources Information Center

    de Pillis, Emmeline; Parsons, Blake

    2013-01-01

    The problem: Motivating and retaining staff had become an ongoing problem at the student newspaper. Student staffers would quit abruptly when overwhelmed or dissatisfied, leaving the newspaper with critical positions vacant. This affected the performance of the newspaper. Method: The newspaper was organized into self directed work teams (SDWTs).…

  20. Reorienting Self-Directed Learning for the Creative Digital Era

    ERIC Educational Resources Information Center

    Karakas, Fahri; Manisaligil, Alperen

    2012-01-01

    Purpose: The purpose of this paper is to identify the new role that human resource developers play in the globally connected workplace. Towards that end, this paper explores the changing landscape of self-directed learning (SDL) within the digital ecosystem based on the concept of World 2.0. Design/methodology/approach: This paper reviews and…

  1. Self-Directed Lifelong Learning in Hybrid Learning Configurations

    ERIC Educational Resources Information Center

    Cremers, Petra H. M.; Wals, Arjen E. J.; Wesselink, Renate; Nieveen, Nienke; Mulder, Martin

    2014-01-01

    Present-day students are expected to be lifelong learners throughout their working life. Higher education must therefore prepare students to self-direct their learning beyond formal education, in real-life working settings. This can be achieved in so-called hybrid learning configurations in which working and learning are integrated. In such a…

  2. Self-Directed Learning: A Tool for Lifelong Learning

    ERIC Educational Resources Information Center

    Boyer, Stefanie L.; Edmondson, Diane R.; Artis, Andrew B.; Fleming, David

    2014-01-01

    A meta-analytic review of self-directed learning (SDL) research over 30 years, five countries, and across multiple academic disciplines is used to explore its relationships with five key nomologically related constructs for effective workplace learning. The meta-analysis revealed positive relationships between SDL and internal locus of control,…

  3. Mid-Career Adults in Self-Directed Graduate Programs.

    ERIC Educational Resources Information Center

    Beitler, Michael A.

    A study investigated the experience of midcareer adults in self-directed graduate programs. It explored two questions in the researcher's personal experience: as a learner, what caused the researcher's change in learning-orientation from goal- to learning-oriented and, as a teacher, could the researcher justify using both self- and…

  4. Reorienting Self-Directed Learning for the Creative Digital Era

    ERIC Educational Resources Information Center

    Karakas, Fahri; Manisaligil, Alperen

    2012-01-01

    Purpose: The purpose of this paper is to identify the new role that human resource developers play in the globally connected workplace. Towards that end, this paper explores the changing landscape of self-directed learning (SDL) within the digital ecosystem based on the concept of World 2.0. Design/methodology/approach: This paper reviews and…

  5. The Self-Directed Learner. Helping Children To Learn Series.

    ERIC Educational Resources Information Center

    Smith, Carl B.

    This short book gives an overview of a curriculum plan, a plan to develop the kind of learners that young children should become. The purpose of this self-directed learner curriculum is to help parents and educators guide young learners so they become capable, purposeful, responsible citizens. It provides an outline of the steps needed to develop…

  6. Web Interface Design Principles for Adults' Self-Directed Learning

    ERIC Educational Resources Information Center

    Firat, Mehmet; Sakar, A. Nurhan; Kabakci Yurdakul, Isil

    2016-01-01

    One of the most important features which e-learning tools and environments must possess within the scope of lifelong learning is self-directed learning, which can be considered as a form of self-learning. The aim of this study was to determine, based on the views and recommendations of experts, interface design principles for the development of…

  7. Sex Bias in the Self-Directed Search Investigative Subscale.

    ERIC Educational Resources Information Center

    Aronowitz, Abby; And Others

    1985-01-01

    The investigative subscale of the Holland Self-Directed Search (SDS) vocational interest inventory was examined for sex-role stereotyping. Male and female psychology researchers and practitioners (N=842) completed the SDS and a revised set of investigative items. Results indicated that the SDS investigative items contain sex bias. (Author/NRB)

  8. Personal Learning Environments: A Solution for Self-Directed Learners

    ERIC Educational Resources Information Center

    Haworth, Ryan

    2016-01-01

    In this paper I discuss "personal learning environments" and their diverse benefits, uses, and implications for life-long learning. Personal Learning Environments (PLEs) are Web 2.0 and social media technologies that enable individual learners the ability to manage their own learning. Self-directed learning is explored as a foundation…

  9. Self-directed Learning to Educate Medical Educators. Part 1: How Do We Use Self-directed Learning?

    ERIC Educational Resources Information Center

    Hammond, Merryl; Collins, Rob

    1987-01-01

    Described are seven steps used to help self-directed learners to work through the Diploma in Primary Health Care (Education) course at the University of Witwatersrand. The steps are: situation analysis; compilation of a competency profile; self-assessment of learning needs; writing learning objectives; compilation of a learning agreement;…

  10. Self-directed Learning to Educate Medical Educators. Part 1: How Do We Use Self-directed Learning?

    ERIC Educational Resources Information Center

    Hammond, Merryl; Collins, Rob

    1987-01-01

    Described are seven steps used to help self-directed learners to work through the Diploma in Primary Health Care (Education) course at the University of Witwatersrand. The steps are: situation analysis; compilation of a competency profile; self-assessment of learning needs; writing learning objectives; compilation of a learning agreement;…

  11. Developing the Self-Directed Learning Instructional Model to Enhance English Reading Ability and Self-Directed Learning of Undergraduate Students

    ERIC Educational Resources Information Center

    Wichadee, Saovapa

    2011-01-01

    The purposes of this study were to develop the instructional model for enhancing self-directed learning skills of Bangkok University students, study the impacts of the model on their English reading comprehension and self-directed learning ability as well as explore their opinion towards self-directed learning. The model development process…

  12. Developing the Self-Directed Learning Instructional Model to Enhance English Reading Ability and Self-Directed Learning of Undergraduate Students

    ERIC Educational Resources Information Center

    Wichadee, Saovapa

    2011-01-01

    The purposes of this study were to develop the instructional model for enhancing self-directed learning skills of Bangkok University students, study the impacts of the model on their English reading comprehension and self-directed learning ability as well as explore their opinion towards self-directed learning. The model development process…

  13. Analysis of self-directed mastery learning of honors physics

    NASA Astrophysics Data System (ADS)

    Athens, Wendy

    Self-directed learning (SDL) is an important life skill in a knowledge-based society and prepares students to persist, manage their time and resources, use logic to construct their knowledge, argue their views, and collaborate. The purpose of this study was to facilitate mastery of physics concepts through self-directedness in formative testing with feedback, a choice of learning activities, and multiple forms of support. This study was conducted within two sections of honors physics at a private high school (N=24). Students' learning activity choices, time investments, and perceptions (assessed through a post survey) were tracked and analyzed. SDL readiness was linked to success in mastering physics concepts. The three research questions pursued in this study were: What SDL activities did honors physics students choose in their self-directed mastery learning environment? How many students achieved concept mastery and how did they spend their time? Did successful and unsuccessful students perceive the self-directed mastery learning environment differently? Only seven of 24 students were successful in passing the similar concept-based unit tests within four tries, and these seven students were separated into a "successful" group and the other 17 into an "unsuccessful" group. Differences between the two groups were analyzed. A profile of a self-directed secondary honors physics student emerged. A successful self-directed student invested more time learning from activities rather than simply completing them, focused on learning concepts more than rote operations, intentionally selected activities to fill in gaps of knowledge and practice concepts, actively constructed knowledge into a cognitive framework, engaged in academic discourse with instructor and peers as they made repeated attempts to master content and pass the test given constructive feedback, used a wide variety of learning resources, and managed their workload to meet deadlines. This capstone study found

  14. Cooperation, clumping and the evolution of multicellularity.

    PubMed

    Biernaskie, Jay M; West, Stuart A

    2015-08-22

    The evolution of multicellular organisms represents one of the major evolutionary transitions in the history of life. A potential advantage of forming multicellular clumps is that it provides an efficiency benefit to pre-existing cooperation, such as the production of extracellular 'public goods'. However, this is complicated by the fact that cooperation could jointly evolve with clumping, and clumping could have multiple consequences for the evolution of cooperation. We model the evolution of clumping and a cooperative public good, showing that (i) when considered separately, both clumping and public goods production gradually increase with increasing genetic relatedness; (ii) in contrast, when the traits evolve jointly, a small increase in relatedness can lead to a major shift in evolutionary outcome—from a non-clumping state with low public goods production to a cooperative clumping state with high values of both traits; (iii) high relatedness makes it easier to get to the cooperative clumping state and (iv) clumping can be inhibited when it increases the number of cells that the benefits of cooperation must be shared with, but promoted when it increases relatedness between those cells. Overall, our results suggest that public goods sharing can facilitate the formation of well-integrated cooperative clumps as a first step in the evolution of multicellularity. © 2015 The Author(s).

  15. Cooperation, clumping and the evolution of multicellularity

    PubMed Central

    Biernaskie, Jay M.; West, Stuart A.

    2015-01-01

    The evolution of multicellular organisms represents one of the major evolutionary transitions in the history of life. A potential advantage of forming multicellular clumps is that it provides an efficiency benefit to pre-existing cooperation, such as the production of extracellular ‘public goods’. However, this is complicated by the fact that cooperation could jointly evolve with clumping, and clumping could have multiple consequences for the evolution of cooperation. We model the evolution of clumping and a cooperative public good, showing that (i) when considered separately, both clumping and public goods production gradually increase with increasing genetic relatedness; (ii) in contrast, when the traits evolve jointly, a small increase in relatedness can lead to a major shift in evolutionary outcome—from a non-clumping state with low public goods production to a cooperative clumping state with high values of both traits; (iii) high relatedness makes it easier to get to the cooperative clumping state and (iv) clumping can be inhibited when it increases the number of cells that the benefits of cooperation must be shared with, but promoted when it increases relatedness between those cells. Overall, our results suggest that public goods sharing can facilitate the formation of well-integrated cooperative clumps as a first step in the evolution of multicellularity. PMID:26246549

  16. Collective Chemotaxis through Noisy Multicellular Gradient Sensing

    NASA Astrophysics Data System (ADS)

    Varennes, Julien; Han, Bumsoo; Mugler, Andrew

    2016-08-01

    Collective cell migration in response to a chemical cue occurs in many biological processes such as morphogenesis and cancer metastasis. Clusters of migratory cells in these systems are capable of responding to gradients of less than 1% difference in chemical concentration across a cell length. Multicellular systems are extremely sensitive to their environment and while the limits to multicellular sensing are becoming known, how this information leads to coherent migration remains poorly understood. We develop a computational model of multicellular sensing and migration in which groups of cells collectively measure noisy chemical gradients. The output of the sensing process is coupled to individual cells polarization to model migratory behavior. Through the use of numerical simulations, we find that larger clusters of cells detect the gradient direction with higher precision and thus achieve stronger polarization bias, but larger clusters also induce more drag on collective motion. The trade-off between these two effects leads to an optimal cluster size for most efficient migration. We discuss how our model could be validated using simple, phenomenological experiments.

  17. Lifelong learning in otolaryngology: self-directed learning.

    PubMed

    Schweinfurth, John M

    2007-12-01

    Although nothing in didactic form approaches the learning experience of the real world, the educational process up to graduation is based on a teacher-directed model of learning. Active engagement in self-planned learning activities tends to be more effective than passive learning. Lifelong learning involves finding and implementing solutions to everyday problems encountered in the clinic, emergency room, and operating room and on the wards. The process by which much of this education occurs is via self-directed learning, in which learners challenge themselves to pursue activities that arise from their own experiences using their own emerging styles. The acquisition of self-directed learning is a complex process that involves numerous skills and competencies relied upon to complete challenges.

  18. Self-Directed Learning: A Cognitive and Computational Perspective.

    PubMed

    Gureckis, Todd M; Markant, Douglas B

    2012-09-01

    A widely advocated idea in education is that people learn better when the flow of experience is under their control (i.e., learning is self-directed). However, the reasons why volitional control might result in superior acquisition and the limits to such advantages remain poorly understood. In this article, we review the issue from both a cognitive and computational perspective. On the cognitive side, self-directed learning allows individuals to focus effort on useful information they do not yet possess, can expose information that is inaccessible via passive observation, and may enhance the encoding and retention of materials. On the computational side, the development of efficient "active learning" algorithms that can select their own training data is an emerging research topic in machine learning. This review argues that recent advances in these related fields may offer a fresh theoretical perspective on how people gather information to support their own learning.

  19. Self-directed learning and research attitudes among medical students.

    PubMed

    Mahmud, Waqas; Haroon, Mustafa; Munir, Ahmed; Hyder, Omar

    2014-03-01

    To describe the correlation between Self-directed Learning (SDL) and medical students' attitude towards research, based on the premise that self-directed learners are independent, motivated, and curious learners. Observational cross-sectional study. Rawalpindi Medical College, Rawalpindi, from August 2011 to January 2012. One hundred and ninety-four students of final (5th) year class at Rawalpindi Medical College, Rawalpindi participated in this cross-sectional study. SDL ability of students was measured using Oddi's Continuing Learning Inventory (OCLI) whereas Attitude Towards Research (ATR) scale was used to measure their research attitudes. Spearman's rank-order analysis was performed to measure correlation between SDL scores on OCLI and all the 18 items on ATR scale. Statistically significant relationships with correlation coefficients ranging from +0.12 to +0.32 were found for the correlation between scores on the OCLI and eleven statements highlighting research use and positive attributes of research (14 items). Those students who participated in extra-curricular research projects (n=58, 29.9%) had relatively higher scores on OCLI as compared to those who did not participate (n=136, 70.1%, p=0.041). Self-directed learners show a positive attitude towards research, though the relationship is not strong.

  20. Supporting Reflection on Self-Directed Learning Process in Hyperspace

    NASA Astrophysics Data System (ADS)

    Kashihara, Akihiro; Sakamoto, Masanao; Hasegawa, Shinobu; Toyoda, Jun'ichi

    Hypermedia/hypertext-based resources for learning generally provide learners with hyperspace, which consists of pages and links among the pages. In the hyperspace, they can navigate the pages in a self-directed way to learn the domain concepts/knowledge. The navigation often involves constructing knowledge, in which they would make semantic relationships among the contents learned in the navigated pages. Such self-directed learning in hyperspace requires learners to reflect on their knowledge construction process, which they have carried out so far, since what and how they have learned becomes hazy as the navigation progresses. However, it is hard for them to keep reflection during navigating hyperspace. The main issue addressed in this paper is how to facilitate learners' reflection to promote their self-directed learning. Our approach to this issue is to provide learners with a learning tool, which allows learners to annotate their navigation history representation with their knowledge construction process. The annotated navigation history enables them to reflect on their knowledge construction process. This paper also demonstrates an interactive history, which generates the annotated navigation history from learners' annotation. It also generates a knowledge map that visualizes the semantic relationships among the pages learners have learned in hyperspace. This paper also describes a case study with the interactive history. The results indicate that it facilitates reflection on knowledge construction process carried out in hyperspace.

  1. Fibroblast spheroids as a model to study sustained fibroblast quiescence and their crosstalk with tumor cells.

    PubMed

    Salmenperä, Pertteli; Karhemo, Piia-Riitta; Räsänen, Kati; Laakkonen, Pirjo; Vaheri, Antti

    2016-07-01

    Stromal fibroblasts have an important role in regulating tumor progression. Normal and quiescent fibroblasts have been shown to restrict and control cancer cell growth, while cancer-associated, i. e. activated fibroblasts have been shown to enhance proliferation and metastasis of cancer cells. In this study we describe generation of quiescent fibroblasts in multicellular spheroids and their effects on squamous cell carcinoma (SCC) growth in soft-agarose and xenograft models. Quiescent phenotype of fibroblasts was determined by global down-regulation of expression of genes related to cell cycle and increased expression of p27. Interestingly, microarray analysis showed that fibroblast quiescence was associated with similar secretory phenotype as seen in senescence and they expressed senescence-associated-β-galactosidase. Quiescent fibroblasts spheroids also restricted the growth of RT3 SCC cells both in soft-agarose and xenograft models unlike proliferating fibroblasts. Restricted tumor growth was associated with marginally increased tumor cell senescence and cellular differentiation, showed with senescence-associated-β-galactosidase and cytokeratin 7 staining. Our results show that the fibroblasts spheroids can be used as a model to study cellular quiescence and their effects on cancer cell progression. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Development of Three-Dimensional Multicellular Tissue-Like Constructs for Mutational Analysis Using Macroporous Microcarriers

    NASA Technical Reports Server (NTRS)

    Jordan, Jacqueline A.; Fraga, Denise N.; Gonda, Steve R.

    2002-01-01

    A three-dimensional (3-D), tissue-like model was developed for the genotoxic assessment of space environment. In previous experiments, we found that culturing mammalian cells in a NASA-designed bioreactor, using Cytodex-3 beads as a scaffold, generated 3-D multicellular spheroids. In an effort to generate scaffold-free spheroids, we developed a new 3-D tissue-like model by coculturing fibroblast and epithelial cell in a NASA bioreactor using macroporous Cultispher-S(TradeMark) microcarriers. Big Blue(Registered Trademark) Rat 2(Lambda) fibroblasts, genetically engineered to contain multiple copies (>60 copies/cell) of the Lac I target gene, were cocultured with radio-sensitive human epithelial cells, H184F5. Over an 8-day period, samples were periodically examined by microscopy and histology to confirm cell attachment, growth, and viability. Immunohistochemistry and western analysis were used to evaluate the expression of specific cytoskeletal and adhesion proteins. Key cell culture parameters (glucose, pH, and lactate concentrations) were monitored daily. Controls were two-dimensional mono layers of fibroblast or epithelial cells cultured in T-flasks. Analysis of 3-D spheroids from the bioreactor suggests fibroblast cells attached to and completely covered the bead surface and inner channels by day 3 in the bioreactor. Treatment of the 3-day spheroids with dispase II dissolved the Cultisphers(TradeMark) and produced multicellular, bead-less constructs. Immunohistochemistry confirmed the presence of vi.mentin, cytokeratin and E-cadherin in treated spheroids. Examination of the dispase II treated spheroids with transmission electron microscopy (TEM) also showed the presence of desmosomes. These results suggest that the controlled enzymatic degradation of an artificial matrix in the low shear environment of the NASA-designed bioreactor can produce 3-D tissue-like spheroids. 2

  3. Self-directed Learning and Its Impact on Menopausal Symptoms

    PubMed Central

    Yazdkhasti, Mansoureh; Keshavarz, Maryam; Mahmoodi, Zohreh; Hosseini, Agha Fatemeh

    2014-01-01

    Background: One of the main criteria to verify the effectiveness of a health training program is to measure quality of life in menopausal women. Objectives: Hence the aim of this review was to evaluate the effects of self-directed learning (SDL) on MENQOl. Patients and Methods: The present single blind field study was conducted in Saadatmandi Health Center of Robat Karim (Iran, Southwest of Tehran Province) from August to December 2010. One handred and ten menopausal women were selected using convenience sampling method and then divided into two experimental (Self-directed Learning) and control groups of 55 each. Four manuals were developed to guide the women in the experimental group containing practical ways to treat menopausal symptoms. They were distributed among the participants for four weeks on a specific day. Menopausal Specific Quality of Life Questionnaire (MENQOL) was used to determine and compare quality of life scores of these women (before and three months after intervention sessions). The control group did not receive any intervention. Statistical analysis was performed by SPSS/16 software using Kolmogorov-Sminov, ANOVA, independent paired t test and Chi-square test. Results: There were significant statistical differences between two groups regarding the age of subjects; age of menopause; economic, educational and employment status; number of dead and living children; BMI and vasomotor, physical, sexual and psycho-social postmenopausal symptoms. The implementation of Self-directed Learning (SDL) model leads to a significant statistical difference in scores of vasomotor symptoms (16.32 ± 5.92 to 13.26 ± 5.31), psychosocial symptoms (34.8 ± 11 to 27.18 ± 10.83), physical symptoms (75.02 ± 18.07 to 61.42 ± 15.49), sexual symptoms (15.36 ± 6.10 to 12.00 ± 4.97) and the overall score for quality of life (141.5 ± 41.09 to 113.86 ± 36.6) (P < 0.001). No significant changes were found in the QOL scores of the control group. Conclusions

  4. An Evo-Devo Perspective on Multicellular Development of Myxobacteria.

    PubMed

    Arias Del Angel, Juan A; Escalante, Ana E; Martínez-Castilla, León Patricio; Benítez, Mariana

    2017-01-01

    The transition to multicellularity, recognized as one the major transitions in evolution, has occurred independently several times. While multicellular development has been extensively studied in zygotic organisms including plant and animal groups, just a few aggregative multicellular organisms have been employed as model organisms for the study of multicellularity. Studying different evolutionary origins and modes of multicellularity enables comparative analyses that can help identifying lineage-specific aspects of multicellular evolution and generic factors and mechanisms involved in the transition to multicellularity. Among aggregative multicellular organisms, myxobacteria are a valuable system to explore the particularities that aggregation confers to the evolution of multicellularity and mechanisms shared with clonal organisms. Moreover, myxobacteria species develop fruiting bodies displaying a range of morphological diversity. In this review, we aim to synthesize diverse lines of evidence regarding myxobacteria development and discuss them in the context of Evo-Devo concepts and approaches. First, we briefly describe the developmental processes in myxobacteria, present an updated comparative analysis of the genes involved in their developmental processes and discuss these and other lines of evidence in terms of co-option and developmental system drift, two concepts key to Evo-Devo studies. Next, as has been suggested from Evo-Devo approaches, we discuss how broad comparative studies and integration of diverse genetic, physicochemical, and environmental factors into experimental and theoretical models can further our understanding of myxobacterial development, phenotypic variation, and evolution.

  5. Integration of single and multicellular wound responses

    PubMed Central

    Clark, Andrew G.; Miller, Ann L.; Vaughan, Emily; Yu, Hoi-Ying E.; Penkert, Rhiannon; Bement, William M.

    2013-01-01

    Summary Single cells and multicellular tissues rapidly heal wounds. These processes are considered distinct, but one mode of healing—Rho GTPase-dependent formation and closure of a purse string of actin filaments (F-actin) and myosin-2 around wounds—occurs in single cells (1,2) and in epithelia (3-10). Here we show that wounding of one cell in Xenopus embryos elicits Rho GTPase activation around the wound and at the nearest cell-cell junctions in the neighbor cells. F-actin and myosin-2 accumulate at the junctions as well as around the wound itself, and as the resultant actomyosin array closes over the wound site, junctional F-actin and myosin-2 become mechanically integrated with the actin and myosin-2 around the wound, forming a hybrid purse string. When cells are ablated rather than wounded, Rho GTPase activation and F-actin accumulation occur at cell-cell junctions surrounding the ablated cell, and the purse string closes the hole in the epithelium. Elevation of intracellular free calcium, an essential upstream signal for the single cell wound response (2,11), also occurs at the cell-cell contacts and in neighbor cells. Thus, the single and multicellular purse string wound responses represent points on a signaling and mechanical continuum that are integrated by cell-cell junctions. PMID:19631537

  6. Chinese baccalaureate nursing students' readiness for self-directed learning.

    PubMed

    Yuan, Hao Bin; Williams, Beverly A; Fang, Jin Bo; Pang, Dong

    2012-05-01

    This descriptive cross-sectional study was conducted with 536 Chinese nursing students to explore students' readiness for self-directed learning (SDL). The Self-Directed Learning Readiness (SDLR) Scale for nursing education (Chinese translation version) was used. The value of the content validity index tested by five experts was 0.915. A measure of internal consistency (Cronbach's alpha) was 0.925 on the total scale. Students possessed readiness for SDL with a mean score of 157.72 (S.D.=15.08, 62.3% in high level, and 37.7% in low level). The attributes of Chinese students, such as a strong sense of responsibility and perseverance, due diligence and rigorous self-discipline, enable students to take the initiative and responsibility for their own learning. The existing variation in students' readiness for SDL is helpful in identifying student characteristics that might be used to modify learning activities for these students. Senior students had higher scores for SDLR than junior students. This finding likely reflects the maturational process of developing self-directedness. Promoting SDL skills is a challenging process for faculty members and students. It is helpful if nurse educators assess the learning styles and preferences of their students in order to determine the level of SDL activities to include from year to year in the curriculum.

  7. Analysis of Self-Directed Learning upon Student of Mathematics Education Study Program

    ERIC Educational Resources Information Center

    Kleden, Maria Agustina

    2015-01-01

    Various studies have rendered self-directed learning disposition to be significant in the learning of mathematics, however several previous studies have pointed the level of self-directed learning disposition to be at a low point. This research is aimed to enhance self-directed learning through implementing a metacognitive strategy in learning…

  8. The Influence of Complexity and Uncertainty on Self-Directed Team Learning

    ERIC Educational Resources Information Center

    Gray, David

    2012-01-01

    To help increase the effectiveness of self-directed teams, this paper studies the attitudes and behaviour of self-directed team members during the course of a computer simulated marketing strategy game. Self-directed teams are used widely throughout organisations yet receive little scrutiny when they undertake a task which is subject to conditions…

  9. Resistance to Self-Direction in Adult Learning: Myths and Misunderstandings.

    ERIC Educational Resources Information Center

    Brockett, Ralph G.

    1994-01-01

    Resistance to self-direction in learning often results from misconception: self-direction is all or nothing, implies learning in isolation, is a fad, is not worth the time, is an easy way out for teachers, and is the one best way for adults. The relationship of self-directed learning to humanist concepts also gives rise to resistance. (SK)

  10. The Influence of Complexity and Uncertainty on Self-Directed Team Learning

    ERIC Educational Resources Information Center

    Gray, David

    2012-01-01

    To help increase the effectiveness of self-directed teams, this paper studies the attitudes and behaviour of self-directed team members during the course of a computer simulated marketing strategy game. Self-directed teams are used widely throughout organisations yet receive little scrutiny when they undertake a task which is subject to conditions…

  11. Self-Directed Professionals and Autodidactic Choice: A Framework for Analysis.

    ERIC Educational Resources Information Center

    Bouchard, Paul

    Studies of self-directed learning (SDL) have generally concentrated on who self-directed learners are and what/how they learn. In 1980, Gibbons et al. used biographies of 20 "expert" self-directed learners to explore the principles and determinants of SDL. Tough (1967), Guglielmino (1977), and Spear and Mocker (1984) have respectively…

  12. Multicellular density fluctuations in epithelial monolayers

    NASA Astrophysics Data System (ADS)

    Zehnder, Steven M.; Wiatt, Marina K.; Uruena, Juan M.; Dunn, Alison C.; Sawyer, W. Gregory; Angelini, Thomas E.

    2015-09-01

    Changes in cell size often accompany multicellular motion in tissue, and cell number density is known to strongly influence collective migration in monolayers. Density fluctuations in other forms of active matter have been explored extensively, but not the potential role of density fluctuations in collective cell migration. Here we investigate collective motion in cell monolayers, focusing on the divergent component of the migration velocity field to probe density fluctuations. We find spatial patterns of diverging and converging cell groups throughout the monolayers, which oscillate in time with a period of approximately 3-4 h. Simultaneous fluorescence measurements of a cytosol dye within the cells show that fluid passes between groups of cells, facilitating these oscillations in cell density. Our findings reveal that cell-cell interactions in monolayers may be mediated by intercellular fluid flow.

  13. Finding self-directed learning readiness and fostering self-directed learning through weekly assessment of self-directed learning topics during undergraduate clinical training in ophthalmology.

    PubMed

    Sahoo, Soumendra

    2016-01-01

    To know the individual's current level of readiness and to manage self-directed learning (SDL) not only help learners but also the instructors. The objectives of this study were to find SDL readiness among 4(th) year medical student and to analyze the effect of weekly assessment of SDL topics. This was a cross-sectional study to analyze the effect of weekly assessment of SDL topics in fostering SDL. The 51 4(th) year students during a clinical posting in ophthalmology participated for this study. Each recruited student was tested for SDL readiness through the SDL readiness scale (SDLRS) developed by Lucy Guglielmino (1978), which was validated in our local setting and responses were collected from students on the 1(st) day of the clinical posting. The students chose SDL topics which were assessed on a weekly basis in the form of scenario-based multiple choice questionnaires. Written feedback was collected from each student regarding such activity during their clinical posting, especially to know the actual utilization of SDL hours provided in teaching schedule, satisfaction on the type of questions and motivation for SDL. The mean SDLRS score in male students were 214.15 ± 19.73 and in female 207.95 ± 17.983, which falls under average score as defined in Guglielmino scale. The majority of study population expressed better utilization of SDL study hours because of weekly assessment than when they had no assessment for SDL. Majority of the study population were found to be ready for SDL. The weekly assessment of SDL topics was found to stimulate proper utilization of SDL slots in teaching schedule thereby fostering SDL habits.

  14. Finding self-directed learning readiness and fostering self-directed learning through weekly assessment of self-directed learning topics during undergraduate clinical training in ophthalmology

    PubMed Central

    Sahoo, Soumendra

    2016-01-01

    Background: To know the individual’s current level of readiness and to manage self-directed learning (SDL) not only help learners but also the instructors. The objectives of this study were to find SDL readiness among 4th year medical student and to analyze the effect of weekly assessment of SDL topics. Methodology: This was a cross-sectional study to analyze the effect of weekly assessment of SDL topics in fostering SDL. The 51 4th year students during a clinical posting in ophthalmology participated for this study. Each recruited student was tested for SDL readiness through the SDL readiness scale (SDLRS) developed by Lucy Guglielmino (1978), which was validated in our local setting and responses were collected from students on the 1st day of the clinical posting. The students chose SDL topics which were assessed on a weekly basis in the form of scenario-based multiple choice questionnaires. Written feedback was collected from each student regarding such activity during their clinical posting, especially to know the actual utilization of SDL hours provided in teaching schedule, satisfaction on the type of questions and motivation for SDL. Results: The mean SDLRS score in male students were 214.15 ± 19.73 and in female 207.95 ± 17.983, which falls under average score as defined in Guglielmino scale. The majority of study population expressed better utilization of SDL study hours because of weekly assessment than when they had no assessment for SDL. Conclusions: Majority of the study population were found to be ready for SDL. The weekly assessment of SDL topics was found to stimulate proper utilization of SDL slots in teaching schedule thereby fostering SDL habits. PMID:27563580

  15. Multicellular Computing Using Conjugation for Wiring

    PubMed Central

    Goñi-Moreno, Angel; Amos, Martyn; de la Cruz, Fernando

    2013-01-01

    Recent efforts in synthetic biology have focussed on the implementation of logical functions within living cells. One aim is to facilitate both internal “re-programming” and external control of cells, with potential applications in a wide range of domains. However, fundamental limitations on the degree to which single cells may be re-engineered have led to a growth of interest in multicellular systems, in which a “computation” is distributed over a number of different cell types, in a manner analogous to modern computer networks. Within this model, individual cell type perform specific sub-tasks, the results of which are then communicated to other cell types for further processing. The manner in which outputs are communicated is therefore of great significance to the overall success of such a scheme. Previous experiments in distributed cellular computation have used global communication schemes, such as quorum sensing (QS), to implement the “wiring” between cell types. While useful, this method lacks specificity, and limits the amount of information that may be transferred at any one time. We propose an alternative scheme, based on specific cell-cell conjugation. This mechanism allows for the direct transfer of genetic information between bacteria, via circular DNA strands known as plasmids. We design a multi-cellular population that is able to compute, in a distributed fashion, a Boolean XOR function. Through this, we describe a general scheme for distributed logic that works by mixing different strains in a single population; this constitutes an important advantage of our novel approach. Importantly, the amount of genetic information exchanged through conjugation is significantly higher than the amount possible through QS-based communication. We provide full computational modelling and simulation results, using deterministic, stochastic and spatially-explicit methods. These simulations explore the behaviour of one possible conjugation-wired cellular

  16. Role of Multicellular Aggregates in Biofilm Formation

    PubMed Central

    Kragh, Kasper N.; Hutchison, Jaime B.; Melaugh, Gavin; Rodesney, Chris; Roberts, Aled E. L.; Irie, Yasuhiko; Jensen, Peter Ø.; Diggle, Stephen P.; Allen, Rosalind J.

    2016-01-01

    ABSTRACT In traditional models of in vitro biofilm development, individual bacterial cells seed a surface, multiply, and mature into multicellular, three-dimensional structures. Much research has been devoted to elucidating the mechanisms governing the initial attachment of single cells to surfaces. However, in natural environments and during infection, bacterial cells tend to clump as multicellular aggregates, and biofilms can also slough off aggregates as a part of the dispersal process. This makes it likely that biofilms are often seeded by aggregates and single cells, yet how these aggregates impact biofilm initiation and development is not known. Here we use a combination of experimental and computational approaches to determine the relative fitness of single cells and preformed aggregates during early development of Pseudomonas aeruginosa biofilms. We find that the relative fitness of aggregates depends markedly on the density of surrounding single cells, i.e., the level of competition for growth resources. When competition between aggregates and single cells is low, an aggregate has a growth disadvantage because the aggregate interior has poor access to growth resources. However, if competition is high, aggregates exhibit higher fitness, because extending vertically above the surface gives cells at the top of aggregates better access to growth resources. Other advantages of seeding by aggregates, such as earlier switching to a biofilm-like phenotype and enhanced resilience toward antibiotics and immune response, may add to this ecological benefit. Our findings suggest that current models of biofilm formation should be reconsidered to incorporate the role of aggregates in biofilm initiation. PMID:27006463

  17. Geometry Shapes Evolution of Early Multicellularity

    PubMed Central

    Libby, Eric; Ratcliff, William; Travisano, Michael; Kerr, Ben

    2014-01-01

    Organisms have increased in complexity through a series of major evolutionary transitions, in which formerly autonomous entities become parts of a novel higher-level entity. One intriguing feature of the higher-level entity after some major transitions is a division of reproductive labor among its lower-level units in which reproduction is the sole responsibility of a subset of units. Although it can have clear benefits once established, it is unknown how such reproductive division of labor originates. We consider a recent evolution experiment on the yeast Saccharomyces cerevisiae as a unique platform to address the issue of reproductive differentiation during an evolutionary transition in individuality. In the experiment, independent yeast lineages evolved a multicellular “snowflake-like” cluster formed in response to gravity selection. Shortly after the evolution of clusters, the yeast evolved higher rates of cell death. While cell death enables clusters to split apart and form new groups, it also reduces their performance in the face of gravity selection. To understand the selective value of increased cell death, we create a mathematical model of the cellular arrangement within snowflake yeast clusters. The model reveals that the mechanism of cell death and the geometry of the snowflake interact in complex, evolutionarily important ways. We find that the organization of snowflake yeast imposes powerful limitations on the available space for new cell growth. By dying more frequently, cells in clusters avoid encountering space limitations, and, paradoxically, reach higher numbers. In addition, selection for particular group sizes can explain the increased rate of apoptosis both in terms of total cell number and total numbers of collectives. Thus, by considering the geometry of a primitive multicellular organism we can gain insight into the initial emergence of reproductive division of labor during an evolutionary transition in individuality. PMID:25233196

  18. Multicellular computing using conjugation for wiring.

    PubMed

    Goñi-Moreno, Angel; Amos, Martyn; de la Cruz, Fernando

    2013-01-01

    Recent efforts in synthetic biology have focussed on the implementation of logical functions within living cells. One aim is to facilitate both internal "re-programming" and external control of cells, with potential applications in a wide range of domains. However, fundamental limitations on the degree to which single cells may be re-engineered have led to a growth of interest in multicellular systems, in which a "computation" is distributed over a number of different cell types, in a manner analogous to modern computer networks. Within this model, individual cell type perform specific sub-tasks, the results of which are then communicated to other cell types for further processing. The manner in which outputs are communicated is therefore of great significance to the overall success of such a scheme. Previous experiments in distributed cellular computation have used global communication schemes, such as quorum sensing (QS), to implement the "wiring" between cell types. While useful, this method lacks specificity, and limits the amount of information that may be transferred at any one time. We propose an alternative scheme, based on specific cell-cell conjugation. This mechanism allows for the direct transfer of genetic information between bacteria, via circular DNA strands known as plasmids. We design a multi-cellular population that is able to compute, in a distributed fashion, a Boolean XOR function. Through this, we describe a general scheme for distributed logic that works by mixing different strains in a single population; this constitutes an important advantage of our novel approach. Importantly, the amount of genetic information exchanged through conjugation is significantly higher than the amount possible through QS-based communication. We provide full computational modelling and simulation results, using deterministic, stochastic and spatially-explicit methods. These simulations explore the behaviour of one possible conjugation-wired cellular computing

  19. Simple systems that exhibit self-directed replication

    NASA Technical Reports Server (NTRS)

    Reggia, James A.; Armentrout, Steven L.; Chou, Hui-Hsien; Peng, Yun

    1993-01-01

    Biological experience and intuition suggest that self-replication is an inherently complex phenomenon, and early cellular automata models support that conception. More recently, simpler computational models of self-directed replication called sheathed loops have been developed. It is shown here that 'unsheathing' these structures and altering certain assumptions about the symmetry of their components leads to a family of nontrivial self-replicating structures some substantially smaller and simpler than those previously reported. The dependence of replication time and transition function complexity on initial structure size, cell state symmetry, and neighborhood are examined. These results support the view that self-replication is not an inherently complex phenomenon but rather an emergent property arising from local interactions in systems that can be much simpler than is generally believed.

  20. Infection and cancer in multicellular organisms

    PubMed Central

    Ewald, Paul W.; Swain Ewald, Holly A.

    2015-01-01

    Evolutionary considerations suggest that oncogenic infections should be pervasive among animal species. Infection-associated cancers are well documented in humans and domestic animals, less commonly reported in undomesticated captive animals, and rarely documented in nature. In this paper, we review the literature associating infectious agents with cancer to evaluate the reasons for this pattern. Non-malignant infectious neoplasms occur pervasively in multicellular life, but oncogenic progression to malignancy is often uncertain. Evidence from humans and domestic animals shows that non-malignant infectious neoplasms can develop into cancer, although generally with low frequency. Malignant neoplasms could be difficult to find in nature because of a low frequency of oncogenic transformation, short survival after malignancy and reduced survival prior to malignancy. Moreover, the evaluation of malignancy can be ambiguous in nature, because criteria for malignancy may be difficult to apply consistently across species. The information available in the literature therefore does not allow for a definitive assessment of the pervasiveness of infectious cancers in nature, but the presence of infectious neoplasias and knowledge about the progression of benign neoplasias to cancer is consistent with a widespread but largely undetected occurrence. PMID:26056368

  1. Semiautomatic growth analysis of multicellular tumor spheroids.

    PubMed

    Rodday, Bjoern; Hirschhaeuser, Franziska; Walenta, Stefan; Mueller-Klieser, Wolfgang

    2011-10-01

    Multicellular tumor spheroids (MCTS) are routinely employed as three-dimensional in vitro models to study tumor biology. Cultivation of MCTS in spinner flasks provides better growing conditions, especially with regard to the availability of nutrients and oxygen, when compared with microtiter plates. The main endpoint of drug response experiments is spheroid size. It is common practice to analyze spheroid size manually with a microscope and an ocular micrometer. This requires removal of some spheroids from the flask, which entails major limitations such as loss of MCTS and the risk of contamination. With this new approach, the authors present an efficient and highly reproducible method to analyze the size of complete MCTS populations in culture containers with transparent, flat bottoms. MCTS sediments are digitally scanned and spheroid volumes are calculated by computerized image analysis. The equipment includes regular office hardware (personal computer, flatbed scanner) and software (Adobe Photoshop, Microsoft Excel, ImageJ). The accuracy and precision of the method were tested using industrial precision steel beads with known diameter. In summary, in comparison with other methods, this approach provides benefits in terms of semiautomation, noninvasiveness, and low costs.

  2. Promotion of self-directed learning using virtual patient cases.

    PubMed

    Benedict, Neal; Schonder, Kristine; McGee, James

    2013-09-12

    To assess the effectiveness of virtual patient cases to promote self-directed learning (SDL) in a required advanced therapeutics course. Virtual patient software based on a branched-narrative decision-making model was used to create complex patient case simulations to replace lecture-based instruction. Within each simulation, students used SDL principles to learn course objectives, apply their knowledge through clinical recommendations, and assess their progress through patient outcomes and faculty feedback linked to their individual decisions. Group discussions followed each virtual patient case to provide further interpretation, clarification, and clinical perspective. Students found the simulated patient cases to be organized (90%), enjoyable (82%), intellectually challenging (97%), and valuable to their understanding of course content (91%). Students further indicated that completion of the virtual patient cases prior to class permitted better use of class time (78%) and promoted SDL (84%). When assessment questions regarding material on postoperative nausea and vomiting were compared, no difference in scores were found between the students who attended the lecture on the material in 2011 (control group) and those who completed the virtual patient case on the material in 2012 (intervention group). Completion of virtual patient cases, designed to replace lectures and promote SDL, was overwhelmingly supported by students and proved to be as effective as traditional teaching methods.

  3. Promotion of Self-directed Learning Using Virtual Patient Cases

    PubMed Central

    Schonder, Kristine; McGee, James

    2013-01-01

    Objective. To assess the effectiveness of virtual patient cases to promote self-directed learning (SDL) in a required advanced therapeutics course. Design. Virtual patient software based on a branched-narrative decision-making model was used to create complex patient case simulations to replace lecture-based instruction. Within each simulation, students used SDL principles to learn course objectives, apply their knowledge through clinical recommendations, and assess their progress through patient outcomes and faculty feedback linked to their individual decisions. Group discussions followed each virtual patient case to provide further interpretation, clarification, and clinical perspective. Assessments. Students found the simulated patient cases to be organized (90%), enjoyable (82%), intellectually challenging (97%), and valuable to their understanding of course content (91%). Students further indicated that completion of the virtual patient cases prior to class permitted better use of class time (78%) and promoted SDL (84%). When assessment questions regarding material on postoperative nausea and vomiting were compared, no difference in scores were found between the students who attended the lecture on the material in 2011 (control group) and those who completed the virtual patient case on the material in 2012 (intervention group). Conclusion. Completion of virtual patient cases, designed to replace lectures and promote SDL, was overwhelmingly supported by students and proved to be as effective as traditional teaching methods. PMID:24052654

  4. Enhancing nurse carer partnerships: A self-directed learning approach.

    PubMed

    Cleary, Michelle; Freeman, Adele

    2006-07-01

    For many mental health consumers living in the community, friends or relatives provide day-to-day care and support. Consequently, mental health nurses are increasingly required to work collaboratively with carers and integrate their perspective into patient care. Despite this, research suggests that communication between healthcare workers and carers is poor and training in imparting information to carers effectively and encouraging their involvement has been negligible. In recognition of this, it was deemed important to develop a self-directed learning programme for mental health nurses who wish to enhance their skills in carer partnership. Many nurses are interested in developing their clinical leadership abilities and this programme provides an opportunity to demonstrate expertise through portfolio development in a key area of healthcare delivery. This innovative programme provides educative opportunities to nurses who are frequently busy, work rotating rosters, and have competing demands upon their time. It is open to all nurses irrespective of position or setting and utilises a purpose-designed workbook based on contemporary learning principles. This approach is not without its limitations however. In this paper we share our experiences and hope that it may inform others planning innovations to develop practice through education.

  5. Self-directed attention, awareness of bodily states, and suggestibility.

    PubMed

    Scheier, M F; Carver, C S; Gibbons, F X

    1979-09-01

    Two studies tested the hypothesis that self-directed attention would cause increased awareness of internal states and would thus reduce suggestibility effects. Experiment 1 applied this reasoning to the experience of an emotion. Males viewed moderately arousing slides of female nudes after being led to expect the slides to be either highly arousing or nonarousing. As predicted, ratings of the slides corresponded less with these experimentally-manipulated anticipations when self-focus was heightened by the presence of a mirror than when it was not. Experiment 2 examined a different internal experience: the perception of taste. Some subjects were led to expect a strong flavor as part of a test series, and other subjects were led to expect a weak flavor. Subjects high in private self-consciousness were less affected by this expectancy manipulation and more accurate in reporting their actual internal state than were subjects low in private self-consciousness. Discussion centers on the theoretical implications of the findings.

  6. Self-directed learning in nurse education: a review of the literature.

    PubMed

    O'Shea, Ellen

    2003-07-01

    Self-directed learning is essential in assisting nurses to meet the challenges presented in today's health care environment. Nurse educators have an important role to play in assisting nurses to acquire the skills for self-directed learning, and to do this they need to understand the concept of self-directed learning. The aim of this review is to explore the concept of self-directed learning and its use in nurse education. A review of the literature was conducted using CINAHL, Medline and other databases and the keywords 'self-directed learning', 'student nurses', 'classroom', 'nursing education' and 'adult education'. The concept of self-directed learning is based on the principles of adult education and can take many different formats. Self-directed learning has many benefits. However, acquiring the necessary skills is dependent on a students' preference and readiness for self-directed learning and nurse educators' implementation of the concept. In implementing self-directed learning, nurse educators become facilitators of learning and require ongoing staff development. Not all students are self-directed and a variety of teaching methods should be used in curricula. A consensus definition of the concept of lifelong learning does not exist, and students and teachers may have different perspectives on it. Mature students may be more self-directing than school-leavers, and learning styles and readiness to learn need to be assessed when judging the appropriateness of using self-directed learning approaches. However, there are many potential benefits, including increased confidence, autonomy, motivation and preparation for lifelong learning.

  7. Carcinoma-associated fibroblasts: orchestrating the composition of malignancy

    PubMed Central

    Gascard, Philippe; Tlsty, Thea D.

    2016-01-01

    The tumor stroma is no longer seen solely as physical support for mutated epithelial cells but as an important modulator and even a driver of tumorigenicity. Within the tumor stromal milieu, heterogeneous populations of fibroblast-like cells, collectively termed carcinoma-associated fibroblasts (CAFs), are key players in the multicellular, stromal-dependent alterations that contribute to malignant initiation and progression. This review focuses on novel insights into the contributions of CAFs to disease progression, emergent events leading to the generation of CAFs, identification of CAF-specific biomarkers predictive of disease outcome, and recent therapeutic approaches aimed at blunting or reverting detrimental protumorigenic phenotypes associated with CAFs. PMID:27151975

  8. Ferritin nanocontainers that self-direct in synthetic polymer systems

    NASA Astrophysics Data System (ADS)

    Sengonul, Merih C.

    Currently, there are many approaches to introduce functionality into synthetic polymers. Among these, for example, are copolymerization, grafting, and blending methods. However, modifications made by such methods also change the thermodynamics and rheological properties of the polymer system of interest, and each new modification often requires a costly reoptimization of polymer processing. Such a reoptimalization would not be necessary if new functionality could be introduced via a container whose external surface is chemically and physically tuned to interact with the parent polymer. The contents of the container could then be changed without changing other important properties of the parent polymer. In this context this thesis project explores an innovative nanocontainer platform which can be introduced into phase-separating homopolymer blends. Ferritin is a naturally existing nanocontainer that can be used synthetically to package and selectively transport functional moieties to a particular phase that is either in the bulk or on the surface of a homopolymer blend system. The principal focus of this work centers on modifying the surface of wild ferritin to: (1) render modified ferritin soluble in a non-aqueous solvent; and (2) impart it with self-directing properties when exposed to a homopolymer blend surface or incorporated into the bulk of a homopolymer blend. Wild ferritin is water soluble, and this research project successfully modified wild ferritin by grafting either amine-functional poly(ethylene glycol) (PEG) or short-chain alkanes to carbodiimide activated carboxylate groups on ferritin's surface. Such modified ferritin is soluble in dichloromethane (DCM). Modification was confirmed by ion-exchange chromatography, zeta-potential measurements, and electrospray mass spectroscopy. FT-IR was used to quantify the extent of PEGylation of the reaction products through area ratios of the -C-O-C asymmetric stretching vibration of the grafted PEG chains to the

  9. A confirmatory factor analysis of the Self-Directed Learning Readiness Scale.

    PubMed

    Williams, Brett; Brown, Ted

    2013-12-01

    The Self-Directed Learning Readiness Scale measures readiness for self-directed learning among undergraduate healthcare students. While several exploratory factor analyses and one confirmatory factor analysis have examined the psychometric properties of the Self-Directed Learning Readiness Scale, questions have been raised regarding the underlying latent constructs being measured. The objective of this study was to determine the best-fitting Self-Directed Learning Readiness Scale factorial structure among three models published in the literature. Data from the three-factor 40-item Self-Directed Learning Readiness Scale completed by 233 undergraduate paramedic students from four Australian universities (response rate of 26%) were analyzed using maximum likelihood confirmatory factor analysis. Comparison of model fit from the 40-item version was undertaken with the previously documented four-factor 36-item and three-factor 29-item Self-Directed Learning Readiness Scales. The model fit indices of the three one-factor congeneric models with maximum likelihood analysis demonstrate that the 40-item Self-Directed Learning Readiness Scale does not fit the data well. The best fitting model was the four-factor 36-item Self-Directed Learning Readiness Scale followed by the three-factor 29-item models. The confirmatory factor analysis results did not support the overall construct validity of the original 40-item Self-Directed Learning Readiness Scale.

  10. Emotional Intelligence and Self-Directed Learning Readiness among College Students Participating in a Leadership Development Program

    ERIC Educational Resources Information Center

    Radnitzer, Karl David

    2010-01-01

    The purpose of this study was to investigate possible relationships between self-directed learning readiness and emotional intelligence in a leadership development program and if self-directed learning leads to greater self-directed learning capabilities. Prior research has examined self-directed learning and emotional intelligence but never have…

  11. Emotional Intelligence and Self-Directed Learning Readiness among College Students Participating in a Leadership Development Program

    ERIC Educational Resources Information Center

    Radnitzer, Karl David

    2010-01-01

    The purpose of this study was to investigate possible relationships between self-directed learning readiness and emotional intelligence in a leadership development program and if self-directed learning leads to greater self-directed learning capabilities. Prior research has examined self-directed learning and emotional intelligence but never have…

  12. Agent Based Modelling Helps in Understanding the Rules by Which Fibroblasts Support Keratinocyte Colony Formation

    PubMed Central

    Sun, Tao; McMinn, Phil; Holcombe, Mike; Smallwood, Rod; MacNeil, Sheila

    2008-01-01

    Background Autologous keratincoytes are routinely expanded using irradiated mouse fibroblasts and bovine serum for clinical use. With growing concerns about the safety of these xenobiotic materials, it is desirable to culture keratinocytes in media without animal derived products. An improved understanding of epithelial/mesenchymal interactions could assist in this. Methodology/Principal Findings A keratincyte/fibroblast o-culture model was developed by extending an agent-based keratinocyte colony formation model to include the response of keratinocytes to both fibroblasts and serum. The model was validated by comparison of the in virtuo and in vitro multicellular behaviour of keratinocytes and fibroblasts in single and co-culture in Greens medium. To test the robustness of the model, several properties of the fibroblasts were changed to investigate their influence on the multicellular morphogenesis of keratinocyes and fibroblasts. The model was then used to generate hypotheses to explore the interactions of both proliferative and growth arrested fibroblasts with keratinocytes. The key predictions arising from the model which were confirmed by in vitro experiments were that 1) the ratio of fibroblasts to keratinocytes would critically influence keratinocyte colony expansion, 2) this ratio needed to be optimum at the beginning of the co-culture, 3) proliferative fibroblasts would be more effective than irradiated cells in expanding keratinocytes and 4) in the presence of an adequate number of fibroblasts, keratinocyte expansion would be independent of serum. Conclusions A closely associated computational and biological approach is a powerful tool for understanding complex biological systems such as the interactions between keratinocytes and fibroblasts. The key outcome of this study is the finding that the early addition of a critical ratio of proliferative fibroblasts can give rapid keratinocyte expansion without the use of irradiated mouse fibroblasts and bovine

  13. The Relationship between Transformational Leadership and Knowledge Workers' Self-Directed Learning Readiness

    ERIC Educational Resources Information Center

    Aparicio, Ricardo Antonio

    2013-01-01

    The rapid pace of change for knowledge workers competing globally necessitates ongoing continuous learning. Increasingly, knowledge workers will need to be ready--willing and able--to engage in self-directed learning. This makes it important to understand what factors in the work environment might be related to the self-directed learning…

  14. Two Decades of Literature on Self-Directed Learning: A Content Analysis.

    ERIC Educational Resources Information Center

    Brockett, Ralph G.; Stockdale, Susan L.; Fogerson, Dewey L.; Cox, Barry F.; Canipe, James B.; Chuprina, Larissa A.; Donaghy, Robert C.; Chadwell, Nancy E.

    Using a quantitative content analysis approach, a study examined the literature on self direction, or self-directed learning (SDL), that appeared in 14 mainstream adult education journals between 1980-98. The procedure involved classifying, entering, and tallying information on each article through use of an Internet-based program. Results…

  15. Self Directed Support and People with Learning Disabilities: A Review of the Published Research Evidence

    ERIC Educational Resources Information Center

    Harkes, Mary Anne; Brown, Michael; Horsburgh, Dorothy

    2014-01-01

    A systematic literature review was undertaken to determine the evidence base underpinning the strategy of Self Directed Support and whether evidence demonstrates that this policy is accessible to everyone with a learning disability. It also sought to identify whether there were any barriers to Self Directed Support for people with severe or…

  16. The Effects of Self-Directed Teams in an Automotive Manufacturing Environment

    ERIC Educational Resources Information Center

    Shall, David W.

    2010-01-01

    This study compares self-directed work structures to more traditional supervised work structures in order to determine if the expenditures and efforts required to implement self-directed work teams are warranted. Multiple internal performance metrics are examined in comparing plant work structures in various degrees of implementation between…

  17. Conditions Enhancing Self-Directed Learning in the Workplace. A Report to the Participants.

    ERIC Educational Resources Information Center

    1992

    The appreciative inquiry process was used to identify conditions enhancing self-directed learning. Participants in the project did the following: (1) used the five-step process to identify factors/conditions/forces that seemed to cause self-directed learning to occur; (2) created a matrix by combining the factors/conditions/forces with six…

  18. I Feel, Therefore, I Learn: The Role of Emotion in Self-Directed Learning

    ERIC Educational Resources Information Center

    Rager, Kathleen B.

    2009-01-01

    It is rare to find the emotional component of self-directed learning discussed explicitly in the literature. This lack is particularly glaring given the interest sparked by recent brain research concerning the importance of emotion in all types of learning as well as by the dramatic increase in self-directed learning in the emotionally charged…

  19. Supporting and Facilitating Self-Directed Learning. ERIC Digest No. 93.

    ERIC Educational Resources Information Center

    Lowry, Cheryl Meredith

    Self-directed learning has been a high-interest topic within the field of adult education for the last decade. The following are among suggestions writers have made about how adult educators can best facilitate self-directed learning: (1) encourage learners to appreciate that they can act on their world individually or collectively to transform…

  20. Academic Performance and the Practice of Self-Directed Learning: The Adult Student Perspective

    ERIC Educational Resources Information Center

    Khiat, Henry

    2017-01-01

    The practice of self-directed learning is important to adult students as it allows them to learn effectively while juggling work, family and other commitments. This study set out to examine the self-directed learning characteristics present in the adult students' study process at the case university. The relationship between the adult students'…

  1. Developing a Self-Directed Computer Training Program for El Camino College Faculty.

    ERIC Educational Resources Information Center

    McAllister, Donald F.

    The purposes of this study were to: (1) establish existing computer literacy levels among faculty members at El Camino College, California; (2) determine the principal obstacles to self-directed computer training, along with strategies designed to overcome these obstacles; and (3) develop recommendations concerning the structure of self-directed,…

  2. The Readiness of Adults with Attention Deficit Hyperactivity Disorder for Self-Directed Learning

    ERIC Educational Resources Information Center

    Wright, Melissa Sue

    2011-01-01

    This study investigated the readiness for self-directed learning of adults with Attention Deficit Hyperactivity Disorder (ADHD), as well as their overall educational experiences. Using Guglielmino's Self-Directed Learning Readiness Scale for Adults (SDLRS-A), the researcher investigated whether the following factors were significantly related to…

  3. Self-Directed Exchange of Credentials. A Model for Learners, Clients and Brokers.

    ERIC Educational Resources Information Center

    Campbell-Thrane, Lucille

    Adults often prefer self-directed learning over teacher-directed, classroom-oriented learning. They feel that their life experiences and self-initiated projects teach them more than they can learn in a formal classroom situation. Persons usually do not pursue such self-directed learning, however, because of conflicting role requirements, a lack of…

  4. A Framework for Developing Self-Directed Technology Use for Language Learning

    ERIC Educational Resources Information Center

    Lai, Chun

    2013-01-01

    Critical to maximizing the potential of technology for learning is enhancing language learners' self-directed use of technology for learning purposes. This study aimed to enhance our understanding of the determinants of self-directed technology use through the construction of a structural equation modelling (SEM) framework of factors and…

  5. Exploring First-Year Undergraduate Medical Students' Self-Directed Learning Readiness to Physiology

    ERIC Educational Resources Information Center

    Abraham, Reem Rachel; Fisher, Murray; Kamath, Asha; Izzati, T. Aizan; Nabila, Saidatul; Atikah, Nik Nur

    2011-01-01

    Medical students are expected to possess self-directed learning skills to pursue lifelong learning. Previous studies have reported that the readiness for self-directed learning depends on personal attributes as well as the curriculum followed in institutions. Melaka Manipal Medical College of Manipal University (Karnataka, India) offers a Bachelor…

  6. Learning and Student Interaction in Small Self-Directed College Groups. Final Report.

    ERIC Educational Resources Information Center

    Beach, Leslie R.

    In a self-directed student group, learning activities are controlled and directed by the students themselves. This approach to learning was investigated at Hope College to: (1) explore the amount and patterns of interaction observable in small self-directed groups, (2) assess conditions and events in group interaction which enhance or inhibit…

  7. Academic Performance and the Practice of Self-Directed Learning: The Adult Student Perspective

    ERIC Educational Resources Information Center

    Khiat, Henry

    2017-01-01

    The practice of self-directed learning is important to adult students as it allows them to learn effectively while juggling work, family and other commitments. This study set out to examine the self-directed learning characteristics present in the adult students' study process at the case university. The relationship between the adult students'…

  8. Using Study Plans to Develop Self-Directed Learning Skills: Implications from a Pilot Project

    ERIC Educational Resources Information Center

    Du, Fengning

    2012-01-01

    Self-directed learning has been lauded as a powerful learner-centered approach to involve students in every aspect of their learning. This article depicts a pilot project utilizing study plan as a vehicle to promote self-directed learning in an intensive and teacher-dominant college language program. This article seeks to identify both the…

  9. Exploring First-Year Undergraduate Medical Students' Self-Directed Learning Readiness to Physiology

    ERIC Educational Resources Information Center

    Abraham, Reem Rachel; Fisher, Murray; Kamath, Asha; Izzati, T. Aizan; Nabila, Saidatul; Atikah, Nik Nur

    2011-01-01

    Medical students are expected to possess self-directed learning skills to pursue lifelong learning. Previous studies have reported that the readiness for self-directed learning depends on personal attributes as well as the curriculum followed in institutions. Melaka Manipal Medical College of Manipal University (Karnataka, India) offers a Bachelor…

  10. Assessment of Animated Self-Directed Learning Activities Modules for Children's Number Sense Development

    ERIC Educational Resources Information Center

    Yang, Der-Ching; Li, Mao-Neng

    2013-01-01

    The purpose of this study was to examine the relative effectiveness of two different learning modes; namely, a computer animation self-directed learning approach and a paper version of the self-directed learning approach, to 5th-graders' number sense development. Two 5th-grade classes, 30 students each, were selected from a public elementary…

  11. Self-Directed Teams in the Introductory Information Systems Course: Lessons Learned.

    ERIC Educational Resources Information Center

    Buffington, James R.

    Research clearly supports the efficacy of self-directed teams in the learning of information systems (IS) skills. This paper proposes that the use of self-directed teams demands a considerable amount of direction on the part of the instructor. Students in two sections of an introductory IS class were surveyed with explicit questions about their…

  12. Influence of Adult Goal-Setting Instruction on Students' Responsibility toward Self-Directed Competencies

    ERIC Educational Resources Information Center

    Apa Browne, Lynn Geri

    2014-01-01

    Elementary grade students in a mid-Atlantic state school district have not been meeting academic standards on state assessments. Research indicates that academic achievement is connected to self-directed readiness to learn; however, often the instruction in strategies for student self-directed readiness to learn remains teacher-centered. The…

  13. Developing a Self-Directed Computer Training Program for El Camino College Faculty.

    ERIC Educational Resources Information Center

    McAllister, Donald F.

    The purposes of this study were to: (1) establish existing computer literacy levels among faculty members at El Camino College, California; (2) determine the principal obstacles to self-directed computer training, along with strategies designed to overcome these obstacles; and (3) develop recommendations concerning the structure of self-directed,…

  14. Self Directed Support and People with Learning Disabilities: A Review of the Published Research Evidence

    ERIC Educational Resources Information Center

    Harkes, Mary Anne; Brown, Michael; Horsburgh, Dorothy

    2014-01-01

    A systematic literature review was undertaken to determine the evidence base underpinning the strategy of Self Directed Support and whether evidence demonstrates that this policy is accessible to everyone with a learning disability. It also sought to identify whether there were any barriers to Self Directed Support for people with severe or…

  15. The Relationship between Transformational Leadership and Knowledge Workers' Self-Directed Learning Readiness

    ERIC Educational Resources Information Center

    Aparicio, Ricardo Antonio

    2013-01-01

    The rapid pace of change for knowledge workers competing globally necessitates ongoing continuous learning. Increasingly, knowledge workers will need to be ready--willing and able--to engage in self-directed learning. This makes it important to understand what factors in the work environment might be related to the self-directed learning…

  16. Motivational Factors in Self-Directed Informal Learning from Online Learning Resources

    ERIC Educational Resources Information Center

    Song, Donggil; Bonk, Curtis J.

    2016-01-01

    Learning is becoming more self-directed and informal with the support of emerging technologies. A variety of online resources have promoted informal learning by allowing people to learn on demand and just when needed. It is significant to understand self-directed informal learners' motivational aspects, their learning goals, obstacles, and…

  17. A Framework for Developing Self-Directed Technology Use for Language Learning

    ERIC Educational Resources Information Center

    Lai, Chun

    2013-01-01

    Critical to maximizing the potential of technology for learning is enhancing language learners' self-directed use of technology for learning purposes. This study aimed to enhance our understanding of the determinants of self-directed technology use through the construction of a structural equation modelling (SEM) framework of factors and…

  18. Self-Directed Learning and Schooling: Identifying Pertinent Theories and Illustrative Research.

    ERIC Educational Resources Information Center

    Skager, Rodney

    1979-01-01

    Six theoretical positions on human learning are identified as relevant to the development of self-direction: modeling; reinforcement; curiosity motivation; competency motivation; attribution theory and personal causation; and humanism. Four approaches to educational practice associated with self-direction are identified: experimental learning;…

  19. The Factor Structure of the Self-Directed Learning Readiness Scale (SDLRS).

    ERIC Educational Resources Information Center

    Wang, Xiaoping; And Others

    A study involving teachers and administrators from 16 elementary, middle, and high schools in Tennessee investigated the factorial structure of the Self-Directed Learning Readiness Scale (SDLRS). The SDLRS includes 58 Likert-like items designed to measure the readiness of adult learners to assume self-direction in the learning process. Study…

  20. Preferences of a Traditional Extension Audience for Self-Directed Delivery Methods.

    ERIC Educational Resources Information Center

    Caldwell, Allen E.; Richardson, John G.

    1995-01-01

    North Carolina farmers growing barley (n=20) tested 3 self-directed information delivery methods: fact sheets, fact sheets plus audiocassettes, and an extension bulletin/pamphlet. The fact sheet/cassette was preferred by 17 of 20; they achieved significant knowledge gains with self-directed methods. The fact sheet/cassette was considered…

  1. Self-Directed Learning in Gross Human Anatomy: Assessment Outcomes and Student Perceptions

    ERIC Educational Resources Information Center

    Smythe, Gayle; Hughes, Diane

    2008-01-01

    Speech pathology students enrolled in a lecture-based gross human anatomy program completed two out of nine topics in self-directed mode. Student performance in quizzes was compared for the two modes, and the students completed questionnaires on their perceptions of the self-directed mode of delivery. Students performed as well in the first…

  2. Measuring Self-Directed Learning: A Diagnostic Tool for Adult Learners

    ERIC Educational Resources Information Center

    Khiat, Henry

    2015-01-01

    Self-directed learning is an important form of adult learning (Caffarella, 1993; Knowles, 1975; Knowles, Holton & Swanson, 2005; Merriam, 2001; Merriam & Caffarella, 1999). The strategies of self-directed learning allow adult learners to cope better with their studies while fulfilling family, work and other commitments. This study…

  3. The Organization of Future Translators' Self-Directed Learning at US Universities

    ERIC Educational Resources Information Center

    Nakonechna, Alyona

    2017-01-01

    The article deals with studying the peculiarities in the organization of future translators' self-directed learning at US universities. It has been stated that various researches on the problem prove the underestimation of self-directed learning that leads to insufficient professional competency of future translators. It has been found out that to…

  4. Knowledge and Attitudes Associated with Self-Directed and Interpersonal Violent Behaviors among Adolescents.

    ERIC Educational Resources Information Center

    Kotecki, Jerome E.; Torabi, Mohammad R.

    1997-01-01

    Analysis of data from the National Adolescent Student Health Survey examined relationships among knowledge, attitude, and behaviors related to interpersonal and self-directed violence. Results found significant relationships among self-directed violence and knowledge, belief, feeling, and intention to act and between interpersonal violent…

  5. The Effects of Self-Directed Teams in an Automotive Manufacturing Environment

    ERIC Educational Resources Information Center

    Shall, David W.

    2010-01-01

    This study compares self-directed work structures to more traditional supervised work structures in order to determine if the expenditures and efforts required to implement self-directed work teams are warranted. Multiple internal performance metrics are examined in comparing plant work structures in various degrees of implementation between…

  6. Self-Directed Learning in Gross Human Anatomy: Assessment Outcomes and Student Perceptions

    ERIC Educational Resources Information Center

    Smythe, Gayle; Hughes, Diane

    2008-01-01

    Speech pathology students enrolled in a lecture-based gross human anatomy program completed two out of nine topics in self-directed mode. Student performance in quizzes was compared for the two modes, and the students completed questionnaires on their perceptions of the self-directed mode of delivery. Students performed as well in the first…

  7. Using Study Plans to Develop Self-Directed Learning Skills: Implications from a Pilot Project

    ERIC Educational Resources Information Center

    Du, Fengning

    2012-01-01

    Self-directed learning has been lauded as a powerful learner-centered approach to involve students in every aspect of their learning. This article depicts a pilot project utilizing study plan as a vehicle to promote self-directed learning in an intensive and teacher-dominant college language program. This article seeks to identify both the…

  8. Assessment of Animated Self-Directed Learning Activities Modules for Children's Number Sense Development

    ERIC Educational Resources Information Center

    Yang, Der-Ching; Li, Mao-Neng

    2013-01-01

    The purpose of this study was to examine the relative effectiveness of two different learning modes; namely, a computer animation self-directed learning approach and a paper version of the self-directed learning approach, to 5th-graders' number sense development. Two 5th-grade classes, 30 students each, were selected from a public elementary…

  9. Preferences of a Traditional Extension Audience for Self-Directed Delivery Methods.

    ERIC Educational Resources Information Center

    Caldwell, Allen E.; Richardson, John G.

    1995-01-01

    North Carolina farmers growing barley (n=20) tested 3 self-directed information delivery methods: fact sheets, fact sheets plus audiocassettes, and an extension bulletin/pamphlet. The fact sheet/cassette was preferred by 17 of 20; they achieved significant knowledge gains with self-directed methods. The fact sheet/cassette was considered…

  10. Self-Directed Learning: A 2-Year, 4-Year Collaboration for Engineering Students. Working Paper Series.

    ERIC Educational Resources Information Center

    Beston, William; Fellows, Sharon; Culver, Richard

    This paper describes the joint collaboration of Broome Community College (BCC) (New York) and the State University of New York at Binghamton to help their engineering students become self-directed learners (SDL). Gerald Grow's model for staged self-directed learning is presented as a framework for the collaboration, with its four stages of student…

  11. Influence of Adult Goal-Setting Instruction on Students' Responsibility toward Self-Directed Competencies

    ERIC Educational Resources Information Center

    Apa Browne, Lynn Geri

    2014-01-01

    Elementary grade students in a mid-Atlantic state school district have not been meeting academic standards on state assessments. Research indicates that academic achievement is connected to self-directed readiness to learn; however, often the instruction in strategies for student self-directed readiness to learn remains teacher-centered. The…

  12. [Relationship between self-directed learning with learning styles and strategies in medical students].

    PubMed

    Márquez U, Carolina; Fasce H, Eduardo; Pérez V, Cristhian; Ortega B, Javiera; Parra P, Paula; Ortiz M, Liliana; Matus B, Olga; Ibáñez G, Pilar

    2014-11-01

    Self-directed learning (SDL) skills are particularly important in medical education, considering that physicians should be able to regulate their own learning experiences. To evaluate the relationship between learning styles and strategies and self-directed learning in medical students. One hundred ninety nine first year medical students (120 males) participated in the study. Preparation for Independent Learning (EPAI) scale was used to assess self-direction. Schmeck learning strategies scale and Honey and Alonso (CHAEA) scales were used to evaluate learning styles and strategies. Theoretical learning style and deep processing learning strategy had positive correlations with self-direct learning. Medical students with theoretical styles and low retention of facts are those with greater ability to self-direct their learning. Further studies are required to determine the relationship between learning styles and strategies with SDL in medical students. The acquired knowledge will allow the adjustment of teaching strategies to encourage SDL.

  13. Multicellularity in green algae: upsizing in a walled complex.

    PubMed

    Domozych, David S; Domozych, Catherine E

    2014-01-01

    Modern green algae constitute a large and diverse taxonomic assemblage that encompasses many multicellular phenotypes including colonial, filamentous, and parenchymatous forms. In all multicellular green algae, each cell is surrounded by an extracellular matrix (ECM), most often in the form of a cell wall. Volvocalean taxa like Volvox have an elaborate, gel-like, hydroxyproline rich glycoprotein covering that contains the cells of the colony. In "ulvophytes," uronic acid-rich and sulfated polysaccharides are the likely adhesion agents that maintain the multicellular habit. Charophytes also produce polysaccharide-rich cell walls and in late divergent taxa, pectin plays a critical role in cell adhesion in the multicellular complex. Cell walls are products of coordinated interaction of membrane trafficking, cytoskeletal dynamics and the cell's signal transduction machinery responding both to precise internal clocks and external environmental cues. Most often, these activities must be synchronized with the secretion, deposition and remodeling of the polymers of the ECM. Rapid advances in molecular genetics, cell biology and cell wall biochemistry of green algae will soon provide new insights into the evolution and subcellular processes leading to multicellularity.

  14. Triassic origin and early radiation of multicellular volvocine algae.

    PubMed

    Herron, Matthew D; Hackett, Jeremiah D; Aylward, Frank O; Michod, Richard E

    2009-03-03

    Evolutionary transitions in individuality (ETIs) underlie the watershed events in the history of life on Earth, including the origins of cells, eukaryotes, plants, animals, and fungi. Each of these events constitutes an increase in the level of complexity, as groups of individuals become individuals in their own right. Among the best-studied ETIs is the origin of multicellularity in the green alga Volvox, a model system for the evolution of multicellularity and cellular differentiation. Since its divergence from unicellular ancestors, Volvox has evolved into a highly integrated multicellular organism with cellular specialization, a complex developmental program, and a high degree of coordination among cells. Remarkably, all of these changes were previously thought to have occurred in the last 50-75 million years. Here we estimate divergence times using a multigene data set with multiple fossil calibrations and use these estimates to infer the times of developmental changes relevant to the evolution of multicellularity. Our results show that Volvox diverged from unicellular ancestors at least 200 million years ago. Two key innovations resulting from an early cycle of cooperation, conflict and conflict mediation led to a rapid integration and radiation of multicellular forms in this group. This is the only ETI for which a detailed timeline has been established, but multilevel selection theory predicts that similar changes must have occurred during other ETIs.

  15. Multicellularity in green algae: upsizing in a walled complex

    PubMed Central

    Domozych, David S.; Domozych, Catherine E.

    2014-01-01

    Modern green algae constitute a large and diverse taxonomic assemblage that encompasses many multicellular phenotypes including colonial, filamentous, and parenchymatous forms. In all multicellular green algae, each cell is surrounded by an extracellular matrix (ECM), most often in the form of a cell wall. Volvocalean taxa like Volvox have an elaborate, gel-like, hydroxyproline rich glycoprotein covering that contains the cells of the colony. In “ulvophytes,” uronic acid-rich and sulfated polysaccharides are the likely adhesion agents that maintain the multicellular habit. Charophytes also produce polysaccharide-rich cell walls and in late divergent taxa, pectin plays a critical role in cell adhesion in the multicellular complex. Cell walls are products of coordinated interaction of membrane trafficking, cytoskeletal dynamics and the cell’s signal transduction machinery responding both to precise internal clocks and external environmental cues. Most often, these activities must be synchronized with the secretion, deposition and remodeling of the polymers of the ECM. Rapid advances in molecular genetics, cell biology and cell wall biochemistry of green algae will soon provide new insights into the evolution and subcellular processes leading to multicellularity. PMID:25477895

  16. SELF-DIRECTED LEARNING, TEAMWORK, HOLISTIC VIEW AND ORAL HEALTH.

    PubMed

    Leisnert, Leif

    2014-01-01

    The dental program at the Malmö Dental School, the so called Malmö-model, is guided by four linked principles: self-directed learning, teamwork, a holistic view of patient care, and oral health (Fig.1). Self-assessment ability is a critical competence for healthcare professionals, necessary for the successful adaptation to the modern life-long learning environment. Educational research seems to point out two critical factors for the development of such skills, continuous practice of self-assessment and constructive feedback. The first study presented in this thesis assessed students' self-assessment ability by means of the Interactive Examination in a cohort of senior dental students, who had gone through an identical assessment procedure during their second year of studies. The results indicated that self-assessment ability was not directly relevant to subject knowledge. Upon graduation, there were a number of students (10%) with significant self-assessment difficulties. Early detection of students with weak self-assessment abilities appears possible to achieve. The aim of the second study, concerning teamwork and holistic view, was to investigate if highlighting teamwork between dental and dental hygienist students could improve the students' holistic view on patients, as well as their knowledge of, and insight into, each other's future professions. This project showed that by initiating teamwork between dental and dental hygienist students, it was possible to increase students' knowledge on dental hygienists competence, develop students' perceived holistic view on patients, and prepare students for teamwork. The third study explored findings clinicians used when diagnosing chronic periodontitis. A questionnaire was distributed to students, dental teachers and clinical supervisors in the Public Dental Services. Within all categories of clinicians, the majority of the clinicians used deepened pocket, bone loss on x-rays, and bleeding as findings. There were

  17. A conceptual framework for the evolutionary origins of multicellularity

    NASA Astrophysics Data System (ADS)

    Libby, Eric; Rainey, Paul B.

    2013-06-01

    The evolution of multicellular organisms from unicellular counterparts involved a transition in Darwinian individuality from single cells to groups. A particular challenge is to understand the nature of the earliest groups, the causes of their evolution, and the opportunities for emergence of Darwinian properties. Here we outline a conceptual framework based on a logical set of possible pathways for evolution of the simplest self-replicating groups. Central to these pathways is the recognition of a finite number of routes by which genetic information can be transmitted between individual cells and groups. We describe the form and organization of each primordial group state and consider factors affecting persistence and evolution of the nascent multicellular forms. Implications arising from our conceptual framework become apparent when attempting to partition fitness effects at individual and group levels. These are discussed with reference to the evolutionary emergence of individuality and its manifestation in extant multicellular life—including those of marginal Darwinian status.

  18. Tyrosine kinase signaling and the emergence of multicellularity

    PubMed Central

    Miller, W. Todd

    2012-01-01

    Tyrosine phosphorylation is an essential element of signal transduction in multicellular animals. Although tyrosine kinases were originally regarded as specific to the metazoan lineage, it is now clear that they evolved prior to the split between unicellular and multicellular eukaryotes (≈ 600 million years ago). Genome analyses of choanoflagellates and other protists show an abundance of tyrosine kinases that rivals the most complex animals. Some of these kinases are orthologs of metazoan enzymes (e.g., Src), but others display unique domain compositions not seen in any metazoan. Biochemical experiments have highlighted similarities and differences between the unicellular and multicellular tyrosine kinases. In particular, it appears that the complex systems of kinase autoregulation may have evolved later in the metazoan lineage. PMID:22480439

  19. From Prokaryotes to Cancer: Glutamine Flux in Multicellular Units.

    PubMed

    Erez, Ayelet; Kolodkin-Gal, Ilana

    2017-09-01

    Bacteria in nature reside in organized communities, termed biofilms, which are composed of multiple individual cells adhering to each other. Similarly, tumors are a multicellular mass with distinct cellular phenotypes. Both tumors and biofilms are considered to be an active interphase between unicellular and multicellular life states. Because both of these units depend on glutamine for growth and survival, we review here glutamine flux within them as a readout for intra- and inter-commensal metabolism. We suggest that the difference between glutamine fluxes in these cellular communities lies mainly in their global multicellular metabolic organization. Both the differences and similarities described here should be taken into account when considering glutamine-targeting therapeutic approaches. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Fungal evo-devo: organelles and multicellular complexity.

    PubMed

    Jedd, Gregory

    2011-01-01

    Peroxisome-derived Woronin bodies of the Ascomycota phyla, and the endoplasmic reticulum (ER)-derived septal pore cap (SPC) of the Basidiomycota, are both fungal organelles that prevent cytoplasmic bleeding when multicellular hyphal filaments are wounded. Analysis of Woronin body constituent proteins suggests that these organelles evolved in part through gene duplication and co-opting of non-essential genes for new functions, indicating that new organelles can arise through typical evolutionary mechanisms. Interestingly, clades possessing the Woronin body and SPC also produce the largest and most complex multicellular fungal reproductive structures. Certain Woronin body and SPC mutants have defects in growth and development, suggesting functions beyond cellular wound healing. I argue that studying these specialized systems will help to reveal the basis for fungal diversity and provide general principles for co-evolution of organelles and multicellular complexity. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Multi-Cellular Logistics of Collective Cell Migration

    PubMed Central

    Yamao, Masataka; Naoki, Honda; Ishii, Shin

    2011-01-01

    During development, the formation of biological networks (such as organs and neuronal networks) is controlled by multicellular transportation phenomena based on cell migration. In multi-cellular systems, cellular locomotion is restricted by physical interactions with other cells in a crowded space, similar to passengers pushing others out of their way on a packed train. The motion of individual cells is intrinsically stochastic and may be viewed as a type of random walk. However, this walk takes place in a noisy environment because the cell interacts with its randomly moving neighbors. Despite this randomness and complexity, development is highly orchestrated and precisely regulated, following genetic (and even epigenetic) blueprints. Although individual cell migration has long been studied, the manner in which stochasticity affects multi-cellular transportation within the precisely controlled process of development remains largely unknown. To explore the general principles underlying multicellular migration, we focus on the migration of neural crest cells, which migrate collectively and form streams. We introduce a mechanical model of multi-cellular migration. Simulations based on the model show that the migration mode depends on the relative strengths of the noise from migratory and non-migratory cells. Strong noise from migratory cells and weak noise from surrounding cells causes “collective migration,” whereas strong noise from non-migratory cells causes “dispersive migration.” Moreover, our theoretical analyses reveal that migratory cells attract each other over long distances, even without direct mechanical contacts. This effective interaction depends on the stochasticity of the migratory and non-migratory cells. On the basis of these findings, we propose that stochastic behavior at the single-cell level works effectively and precisely to achieve collective migration in multi-cellular systems. PMID:22205934

  2. Participants' Assessment of the Impact of Behavioral Health Self-Direction on Recovery.

    PubMed

    Croft, Bevin; Parish, Susan

    2016-10-01

    Self-direction involves managing a flexible budget, selecting and purchasing services and supports to meet individual needs and preferences. An emerging practice in the behavioral health field, self-direction is part of a systemic shift toward person-centered approaches to service provision. To understand the relationship between recovery and self-direction, the authors conducted a content analysis of 30 in-depth interviews with individuals from two self-direction programs in one state. A positive relationship between self-direction and recovery was established. Meeting basic needs for food, clothing, and shelter are important first steps in the recovery process for self-directing participants. Recovery domains were dynamic and interrelated, with gains in independence, self-esteem, and self-confidence facilitating achievement of goals in other domains. To maximize the benefits of self-direction, program administrators may need to develop clearer program implementation standards and address poverty and limited access to appropriate behavioral health services and supports.

  3. Fungal Cell Cycle: A Unicellular versus Multicellular Comparison.

    PubMed

    Dörter, Ilkay; Momany, Michelle

    2016-12-01

    All cells must accurately replicate DNA and partition it to daughter cells. The basic cell cycle machinery is highly conserved among eukaryotes. Most of the mechanisms that control the cell cycle were worked out in fungal cells, taking advantage of their powerful genetics and rapid duplication times. Here we describe the cell cycles of the unicellular budding yeast Saccharomyces cerevisiae and the multicellular filamentous fungus Aspergillus nidulans. We compare and contrast morphological landmarks of G1, S, G2, and M phases, molecular mechanisms that drive cell cycle progression, and checkpoints in these model unicellular and multicellular fungal systems.

  4. Regulated aggregative multicellularity in a close unicellular relative of metazoa

    PubMed Central

    Sebé-Pedrós, Arnau; Irimia, Manuel; del Campo, Javier; Parra-Acero, Helena; Russ, Carsten; Nusbaum, Chad; Blencowe, Benjamin J; Ruiz-Trillo, Iñaki

    2013-01-01

    The evolution of metazoans from their unicellular ancestors was one of the most important events in the history of life. However, the cellular and genetic changes that ultimately led to the evolution of multicellularity are not known. In this study, we describe an aggregative multicellular stage in the protist Capsaspora owczarzaki, a close unicellular relative of metazoans. Remarkably, transition to the aggregative stage is associated with significant upregulation of orthologs of genes known to establish multicellularity and tissue architecture in metazoans. We further observe transitions in regulated alternative splicing during the C. owczarzaki life cycle, including the deployment of an exon network associated with signaling, a feature of splicing regulation so far only observed in metazoans. Our results reveal the existence of a highly regulated aggregative stage in C. owczarzaki and further suggest that features of aggregative behavior in an ancestral protist may had been co-opted to develop some multicellular properties currently seen in metazoans. DOI: http://dx.doi.org/10.7554/eLife.01287.001 PMID:24368732

  5. Phosphotyrosine signalling and the origin of animal multicellularity

    PubMed Central

    Tong, Kai; Wang, Yuyu

    2017-01-01

    The evolution of multicellular animals (i.e. metazoans) from a unicellular ancestor is one of the most important yet least understood evolutionary transitions. Historically, given its indispensable functions in intercellular communication and exclusive presence in metazoans, phosphotyrosine (pTyr) signalling was considered a metazoan-specific evolutionary innovation that might have contributed to the origin of metazoan multicellularity. However, recent studies have led to a new understanding of pTyr signalling evolution and its role in the metazoan origin. Sequence analyses have unravelled a much earlier emergence of pTyr signalling in eukaryotic evolution. Even so, several distinct properties of holozoan pTyr signalling may have paved the way for a hypothesized functional transition of pTyr signalling at the multicellular origin, from environmental sensing to intercellular communication, and for it to evolve as a powerful intercellular signalling system for multicellularity. Biochemical analyses of premetazoan pTyr signalling components have further revealed the premetazoan origin of many key features of metazoan pTyr signalling, and the metazoan establishment of others, including the Csk-mediated negative regulation of the activity of Src, a conserved tyrosine kinase in the Holozoa. Finally, potential future directions are discussed, with a stress on the biological functions of premetazoan pTyr signalling via newly developed gene manipulation tools in non-animal holozoans. PMID:28768887

  6. Regulated aggregative multicellularity in a close unicellular relative of metazoa.

    PubMed

    Sebé-Pedrós, Arnau; Irimia, Manuel; Del Campo, Javier; Parra-Acero, Helena; Russ, Carsten; Nusbaum, Chad; Blencowe, Benjamin J; Ruiz-Trillo, Iñaki

    2013-12-24

    The evolution of metazoans from their unicellular ancestors was one of the most important events in the history of life. However, the cellular and genetic changes that ultimately led to the evolution of multicellularity are not known. In this study, we describe an aggregative multicellular stage in the protist Capsaspora owczarzaki, a close unicellular relative of metazoans. Remarkably, transition to the aggregative stage is associated with significant upregulation of orthologs of genes known to establish multicellularity and tissue architecture in metazoans. We further observe transitions in regulated alternative splicing during the C. owczarzaki life cycle, including the deployment of an exon network associated with signaling, a feature of splicing regulation so far only observed in metazoans. Our results reveal the existence of a highly regulated aggregative stage in C. owczarzaki and further suggest that features of aggregative behavior in an ancestral protist may had been co-opted to develop some multicellular properties currently seen in metazoans. DOI: http://dx.doi.org/10.7554/eLife.01287.001.

  7. Multicellular Secretory Trichome Development on Soybean and Related Glycine Gynoecia

    USDA-ARS?s Scientific Manuscript database

    Multicellular glandular trichomes form on gynoecia of wild Glycine annual species, annual soybean cultivars, and wild perennial species. These trichomes occur on gynoecia of annual taxa from ovary base to style base, and along style of perennial species. Trichomes form at least two days prior to ant...

  8. Phenotypic Diversity of Multicellular Filamentation in Oral Streptococci

    PubMed Central

    Thurnheer, Thomas; Bagheri, Homayoun C.; Belibasakis, Georgios N.

    2013-01-01

    Filamentous multicellular bacteria are among the most ancient multicellular organisms. They inhabit a great variety of environments and are present in the human body, including the oral cavity. Beside the selective advantages related to the larger size achieved through filamentation, the development of multicellular bacteria can be also driven by simple ecological factors such as birth and death rates at the cellular level. In order to extend earlier results obtained in aquatic species, we investigate the filamentation process of four different strains of oral streptococci, namely S. mutans, S. salivarius, S. oralis and S. anginosus. The results indicate differences in the capacities of different streptococcus species to form filaments, manifested in terms of length and the time-scale of filament elongation. The filamentation pattern of these oral streptococci resembles that of aquatic bacteria, whereby filaments reach a peak length during exponential growth and become short when the population reaches a steady state. Hence, this study validates that multicellularity can be an emergent property of filamentous bacteria of different ecological niches, and that phenotypic differences in filamentation can occur within species of the same genus, in this case oral streptococci. Moreover, given the role that specific oral streptococci can play in the etiology of oral diseases, these results can possibly open new perspectives in the study of the virulence properties of these species. PMID:24086713

  9. Phosphotyrosine signalling and the origin of animal multicellularity.

    PubMed

    Tong, Kai; Wang, Yuyu; Su, Zhixi

    2017-08-16

    The evolution of multicellular animals (i.e. metazoans) from a unicellular ancestor is one of the most important yet least understood evolutionary transitions. Historically, given its indispensable functions in intercellular communication and exclusive presence in metazoans, phosphotyrosine (pTyr) signalling was considered a metazoan-specific evolutionary innovation that might have contributed to the origin of metazoan multicellularity. However, recent studies have led to a new understanding of pTyr signalling evolution and its role in the metazoan origin. Sequence analyses have unravelled a much earlier emergence of pTyr signalling in eukaryotic evolution. Even so, several distinct properties of holozoan pTyr signalling may have paved the way for a hypothesized functional transition of pTyr signalling at the multicellular origin, from environmental sensing to intercellular communication, and for it to evolve as a powerful intercellular signalling system for multicellularity. Biochemical analyses of premetazoan pTyr signalling components have further revealed the premetazoan origin of many key features of metazoan pTyr signalling, and the metazoan establishment of others, including the Csk-mediated negative regulation of the activity of Src, a conserved tyrosine kinase in the Holozoa. Finally, potential future directions are discussed, with a stress on the biological functions of premetazoan pTyr signalling via newly developed gene manipulation tools in non-animal holozoans. © 2017 The Author(s).

  10. miRNA expression profile in multicellular breast cancer spheroids.

    PubMed

    Mandujano-Tinoco, Edna Ayerim; Garcia-Venzor, Alfredo; Muñoz-Galindo, Laura; Lizarraga-Sanchez, Floria; Favela-Orozco, Andrei; Chavez-Gutierrez, Edwin; Krötzsch, Edgar; Salgado, Rosa M; Melendez-Zajgla, Jorge; Maldonado, Vilma

    2017-10-01

    Multicellular Tumor Spheroids develop a heterogeneous micromilieu and different cell populations, thereby constituting a cancer model with intermediate characteristics between in vitro bi-dimensional cultures and in vivo tumors. Multicellular Tumor Spheroids also acquire tumor aggressiveness features due to transcription modulation of coding and non-coding RNA. Utilizing microarray analyses, we evaluated the microRNAs expression profile in MCF-7 breast cancer cells cultured as Multicellular Tumor Spheroids. The expression data was used to predict associated cellular and molecular functions using different software tools. The biological importance of two dysregulated miRNAs (miR-221-3p and miR-187) was studied by functional assays. Finally, the clinical relevance of these dysregulated miRNAs was explored using previously reported data. Thirty-three dysregulated microRNAs were found in MCF-7 Multicellular Tumor Spheroids. miRNA expression changes were closely linked with growth, proliferation, and cell development. miRNA-221-3p and miR-187 were implicated in the acquisition of migration/invasion capacities, sensitivity to the deprivation of growth factors, cell cycle phase regulation, and cell death. A panel of 5 miRNAs, including miR-187, showed a good predictive value in discriminating between low and high-risk groups of breast cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Readiness for self-directed learning among nursing students in Thailand.

    PubMed

    Klunklin, Areewan; Viseskul, Nongkran; Sripusanapan, Acharaporn; Turale, Sue

    2010-06-01

    This study took place in Thailand where didactic and lecture-driven teaching styles are beginning to transform into student-centered methods. At Chiang Mai University Faculty of Nursing in Thailand, the readiness of 272 undergraduate students to undertake self-directed learning was investigated using two instruments: a demographic data questionnaire and Guglielmino's Self Directed Learning Readiness Scale. The study found that the overall self-directed learning readiness of participants was at a high level in the categories of openness to learning opportunities, self-concept as an effective learner, initiative and independence in learning, informed acceptance of responsibility for one's own learning, creativity, and the ability to use basic study and problem-solving skills. The findings provide encouragement to nurse educators to further apply self-directed learning in nursing courses, to improve teaching and learning methods, and promote life-long learning for nurses within Thailand and elsewhere.

  12. Bridging the gap between self-directed learning of nurse educators and effective student support.

    PubMed

    Van Rensburg, Gisela H; Botma, Yvonne

    2015-11-26

    Self-directed learning requires the ability to identify one's own learning needs, develop and implement a plan to gain knowledge and to monitor one's own progress. A lifelong learning approach cannot be forced, since it is in essence an internally driven process. Nurse educators can, however, act as role models to empower their students to become independent learners by modelling their own self-directed learning and applying a number of techniques in supporting their students in becoming ready for self-directed learning.  The aim of the article is to describe the manifestations and implications of the gap between self-directed learning readiness of nurse educators and educational trends in supporting students.  An instrumental case study design was used to gain insight into the manifestations and implications of self-directed learning of nurse educators. Based on the authentic foci of various critical incidents and literature, data were collected and constructed into a fictitious case. The authors then deductively analysed the case by using the literature on self-directed learning readiness as departure point. Four constructs of self-directed learning were identified, namely internal motivation, planning and implementation, self-monitoring and interpersonal communication. Supportive strategies were identified from the available literature.  Nine responses by nurse educators based on the fictitious case were analysed.Analysis showed that readiness for self-directed learning in terms of the identified constructswas interrelated and not mutually exclusive of one other.  The success of lifelong learning is the ability to engage in self-directed learning which requires openness to learning opportunities, good self-concept, taking initiative and illustrating independence in learning. Conscientiousness, an informed acceptance of a responsibility for one's own learning and creativity, is vital to one's future orientation towards goal-directed learning. Knowledge and

  13. On the teaching model of website-based collaborated self-directed study

    NASA Astrophysics Data System (ADS)

    Jing, Zhihua; Zeng, Yingxiong; Wen, Chunyu

    2011-12-01

    Based on the theory of collaborated self-directed study and the strengths of modern education technology, the study explores application of websites for collaborated self-directed college English learning. It introduces the characteristics and functions of the website developed to assist college English teaching in China. It also points out the problems currently existing among teachers and students, and puts forward some suggestions and strategies for the improvement of the application of the website.

  14. NCS-1 dependent learning bonus and behavior outputs of self-directed exploration

    NASA Astrophysics Data System (ADS)

    Mun, Ho-Suk

    Animals explore a new environment and learn about their surroundings. "Exploration" refers to all activities that increase the information obtained from an animal. For this study, I determined a molecule that mediates self-directed exploration, with a particular focus on rearing behavior and vocalization. Rearing can be either self-directed exploration or escape-oriented exploration. Self-directed exploration can be driven by the desire to gather information about environments while escape-oriented exploration can be driven by fear or anxiety. To differentiate between these two concepts, I compared rearing and other behaviors in three different conditions 1) novel dim (safe environment), which induces exploration based rearing; 2) novel bright (fearful environment), which elicits fear driven rearing; and 3) familiar environment as a control. First, I characterized the effects on two distinct types of environment in exploratory behavior and its effect on learning. From this, I determined that self-directed exploration enhances spatial learning while escape-oriented exploration does not produce a learning bonus. Second, I found that NCS-1 is involved in exploration, as well as learning and memory, by testing mice with reduced levels of Ncs-1 by point mutation and also siRNA injection. Finally, I illustrated other behavior outputs and neural substrate activities, which co-occurred during either self-directed or escape-oriented exploration. I found that high-frequency ultrasonic vocalizations occurred during self-directed exploration while low-frequency calls were emitted during escape-oriented exploration. Also, with immediate early gene imaging techniques, I found hippocampus and nucleus accumbens activation in self-directed exploration. This study is the first comprehensive molecular analysis of learning bonus in self-directed exploration. These results may be beneficial for studying underlying mechanisms of neuropsychiatric disease, and also reveal therapeutic

  15. The relationship between assessment methods and self-directed learning readiness in medical education.

    PubMed

    Monroe, Katherine S

    2016-03-11

    This research explored the assessment of self-directed learning readiness within the comprehensive evaluation of medical students' knowledge and skills and the extent to which several variables predicted participants' self-directed learning readiness prior to their graduation. Five metrics for evaluating medical students were considered in a multiple regression analysis. Fourth-year medical students at a competitive US medical school received an informed consent and an online survey. Participants voluntarily completed a self-directed learning readiness scale that assessed four subsets of self-directed learning readiness and consented to the release of their academic records. The assortment of metrics considered in this study only vaguely captured students' self-directedness. The strongest predictors were faculty evaluations of students' performance on clerkship rotations. Specific clerkship grades were mildly predictive of three subscales. The Pediatrics clerkship modestly predicted critical self-evaluation (r=-.30, p=.01) and the Psychiatry clerkship mildly predicted learning self-efficacy (r =-.30, p=.01), while the Junior Surgery clerkship nominally correlated with participants' effective organization for learning (r=.21, p=.05). Other metrics examined did not contribute to predicting participants' readiness for self-directed learning. Given individual differences among participants for the variables considered, no combination of students' grades and/or test scores overwhelmingly predicted their aptitude for self-directed learning. Considering the importance of fostering medical students' self-directed learning skills, schools need a reliable and pragmatic approach to measure them. This data analysis, however, offered no clear-cut way of documenting students' self-directed learning readiness based on the evaluation metrics included.

  16. Deconstructing the effect of self-directed study on episodic memory.

    PubMed

    Markant, Douglas; DuBrow, Sarah; Davachi, Lila; Gureckis, Todd M

    2014-11-01

    Self-directed learning is often associated with better long-term memory retention; however, the mechanisms that underlie this advantage remain poorly understood. This series of experiments was designed to "deconstruct" the notion of self-directed learning, in order to better identify the factors most responsible for these improvements to memory. In particular, we isolated the memory advantage that comes from controlling the content of study episodes from the advantage that comes from controlling the timing of those episodes. Across four experiments, self-directed learning significantly enhanced recognition memory, relative to passive observation. However, the advantage for self-directed learning was found to be present even under extremely minimal conditions of volitional control (simply pressing a button when a participant was ready to advance to the next item). Our results suggest that improvements to memory following self-directed encoding may be related to the ability to coordinate stimulus presentation with the learner's current preparatory or attentional state, and they highlight the need to consider the range of cognitive control processes involved in and influenced by self-directed study.

  17. Self-directed learning in gross human anatomy: assessment outcomes and student perceptions.

    PubMed

    Smythe, Gayle; Hughes, Diane

    2008-01-01

    Speech pathology students enrolled in a lecture-based gross human anatomy program completed two out of nine topics in self-directed mode. Student performance in quizzes was compared for the two modes, and the students completed questionnaires on their perceptions of the self-directed mode of delivery. Students performed as well in the first self-directed topic as they did in lecture-based material, but performance declined significantly on the second self-directed topic. Correlations showed that students who performed well in lecture-based topics also performed well on self-directed topics. The major issues that arose in the student questionnaires were primarily related to the amount of content in the topics and the length of time required for completion. We conclude that there is a strong need for appropriate design of distance education materials to reflect student perceptions of length, content, and time investment, and more importantly that there is a need to ensure extensive communication and support of students studying in distance education/self-directed modes for the first time.

  18. The Impact of Advanced Pharmacy Practice Experiences on Students' Readiness for Self-directed Learning

    PubMed Central

    Haines, Stuart T.; Plaza, Cecilia M.; Sturpe, Deborah A.; Williams, Greg; Rodriguez de Bittner, Magaly A.; Roffman, David S.

    2009-01-01

    Objective To evaluate the impact of advanced pharmacy practice experiences (APPEs) on doctor of pharmacy (PharmD) students' readiness for self-directed learning. Methods The Self-Directed Learning Readiness Scale (SDLRS) was administered to students prior to and after completing their APPEs. SDLRS is a validated instrument that determines the relative degree to which students have the attitudes and motivation to engage in self-directed learning. Results Seventy-seven (64%) students completed the SDLRS prior to starting their APPEs and 80 (67%) students completed the instrument after completing their APPEs. Forty-six (38%) students completed both. Prior to starting their APPEs, 74% of students scored greater than 150 on the SDLRS, indicating a high level of readiness for self-directed learning. No significant difference was found between the mean scores of students who took the SDLRS both prior to (159 ± 20) and after completing their APPEs (159 ± 24; p > 0.05). Conclusion Students at our institution appear to be ready for self-directed learning but APPEs had a minimal impact on their readiness for self-directed learning. PMID:19657498

  19. Yeast biofilm colony as an orchestrated multicellular organism.

    PubMed

    Sťovíček, Vratislav; Váchová, Libuše; Palková, Zdena

    2012-03-01

    Although still often considered as simple unicellular organisms, in natural settings yeast cells tend to organize into intricate multicellular communities. Due to specific mechanisms only feasible at the population level, their capacity for social behavior is advantageous for their survival in a harmful environment. Feral Saccharomyces cerevisiae strains form complex structured colonies, which display many properties typical of natural biofilms causing (among others) serious infections in the human body. In our recent paper, we looked inside a growing colony using two-photon confocal microscopy. This allowed us to elucidate its three-dimensional colony architecture and some mechanisms responsible for community protection. Moreover, we showed how particular protective mechanisms complement each other during colony development and how each of them contributes to its defense against attacks from the environment. Our findings broaden current understanding of microbial multicellularity in general and also shed new light on the enormous resistance of yeast biofilms.

  20. A multicellular view of cytokinesis in epithelial tissue.

    PubMed

    Herszterg, Sophie; Pinheiro, Diana; Bellaïche, Yohanns

    2014-05-01

    The study of cytokinesis in single-cell systems provided a wealth of knowledge on the molecular and biophysical mechanisms controlling daughter cell separation. In this review, we outline recent advances in the understanding of cytokinesis in epithelial tissues. These findings provide evidence for how the cytokinetic machinery adapts to a multicellular context and how the cytokinetic machinery is itself exploited by the tissue for the preservation of tissue function and architecture during proliferation. We propose that cytokinesis in epithelia should be viewed as a multicellular process, whereby the biochemical and mechanical interactions between the dividing cell and its neighbors are essential for successful daughter cell separation while defining epithelial tissue organization and preserving tissue integrity.

  1. Hierarchical Size Scaling during Multicellular Growth and Development.

    PubMed

    Uppaluri, Sravanti; Weber, Stephanie C; Brangwynne, Clifford P

    2016-10-04

    Multicellular organisms must regulate their growth across the diverse length scales of biological organization, but how this growth is controlled from organelle to body, while coordinating interdependent functions at each scale, remains poorly understood. We utilized the C. elegans worm intestine as a model system to identify distinct allometric scaling laws, revealing that the growth of individual structures is differentially regulated during development. We show that the volume of the nucleolus, a subcellular organelle, is directly proportional (isometric) to cell size during larval development. In contrast to findings in a variety of other systems, the size of the nucleus grows more slowly and is hypoallometric to the cell. We further demonstrate that the relative size of the nucleolus, the site of ribosome biogenesis, is predictive of the growth rate of the entire worm. These results highlight the importance of subcellular size for organism-level function in multicellular organisms. Copyright © 2016. Published by Elsevier Inc.

  2. Three-dimensional vertex model for simulating multicellular morphogenesis

    PubMed Central

    Okuda, Satoru; Inoue, Yasuhiro; Adachi, Taiji

    2015-01-01

    During morphogenesis, various cellular activities are spatiotemporally coordinated on the protein regulatory background to construct the complicated, three-dimensional (3D) structures of organs. Computational simulations using 3D vertex models have been the focus of efforts to approach the mechanisms underlying 3D multicellular constructions, such as dynamics of the 3D monolayer or multilayer cell sheet like epithelia as well as the 3D compacted cell aggregate, including dynamic changes in layer structures. 3D vertex models enable the quantitative simulation of multicellular morphogenesis on the basis of single-cell mechanics, with complete control of various cellular activities such as cell contraction, growth, rearrangement, division, and death. This review describes the general use of the 3D vertex model, along with its applications to several simplified problems of developmental phenomena. PMID:27493850

  3. Dynamics of self-directed learning in M.Sc. nursing students: A qualitative research

    PubMed Central

    SHIRAZI, FATEMEH; SHARIF, FARKHONDEH; MOLAZEM, ZAHRA; ALBORZI, MAHBOOBEH

    2017-01-01

    Introduction: Working in the complex and ever changing healthcare settings forces the nurses and nursing students to be equipped with lifelong learning skills. One of the lifelong learning skills is self-directed learning. This study aimed to explore the M.Sc. nursing students’ self-directed learning activities. Methods: A qualitative design using conventional content analysis approach was used in this study. Semi-structured interviews were conducted with twelve Iranian M.Sc. nursing students who were selected using purposive sampling. Results: Data analysis indicated that the M.Sc. nursing students performed different activities in their self-directed learning. These activities were categorized into four main themes and ten subthemes. The main themes were “sensory perceptions”, “knowledge construction”, “problem-centered orientation”, and “interaction with others”. Conclusion: According to the findings, the M.Sc. nursing students performed different intellectual and experiential self-directed activities for promoting their learning. Besides, the students’ perseverance and inquisitiveness played an important role in their self-directed learning in the challenging clinical environments. PMID:28124019

  4. Development of a supported self-directed learning approach for anatomy education.

    PubMed

    Findlater, Gordon S; Kristmundsdottir, Fanney; Parson, Simon H; Gillingwater, Thomas H

    2012-01-01

    The ability to deliver sufficient core anatomical knowledge and understanding to medical students with limited time and resources remains a major challenge for anatomy educators. Here, we report the results of switching from a primarily didactic method of teaching to supported self-directed learning for students studying anatomy as part of undergraduate medicine at the University of Edinburgh. The supported self-directed approach we have developed makes use of an integrated range of resources, including formal lectures and practical sessions (incorporating gross anatomy specimens, medical imaging technologies, anatomical models, clinical scenarios, and surface anatomy workstations). In practical sessions, students are provided with a custom-made workbook that guides them through each session, with academic staff, postgraduate tutors, and near-peer teaching assistants present to deal with misunderstandings and explain more complicated topics. This approach retains many of the best attributes of didactic teaching but blends them with the advantages associated with self-directed learning approaches. The switch to supported self-directed learning-initially introduced in 2005-resulted in a significant improvement in anatomy examination scores over the subsequent period of five years, manifesting as an increase in the average anatomy practical spot examination mark, less students failing to obtain the pass mark and more students passing with distinction. We conclude that the introduction of supported self-directed learning improved students' engagement, leading to deeper learning and better understanding and knowledge of anatomy.

  5. Dynamics of self-directed learning in M.Sc. nursing students: A qualitative research.

    PubMed

    Shirazi, Fatemeh; Sharif, Farkhondeh; Molazem, Zahra; Alborzi, Mahboobeh

    2017-01-01

    Working in the complex and ever changing healthcare settings forces the nurses and nursing students to be equipped with lifelong learning skills. One of the lifelong learning skills is self-directed learning. This study aimed to explore the M.Sc. nursing students' self-directed learning activities. A qualitative design using conventional content analysis approach was used in this study. Semi-structured interviews were conducted with twelve Iranian M.Sc. nursing students who were selected using purposive sampling. Data analysis indicated that the M.Sc. nursing students performed different activities in their self-directed learning. These activities were categorized into four main themes and ten subthemes. The main themes were "sensory perceptions", "knowledge construction", "problem-centered orientation", and "interaction with others". According to the findings, the M.Sc. nursing students performed different intellectual and experiential self-directed activities for promoting their learning. Besides, the students' perseverance and inquisitiveness played an important role in their self-directed learning in the challenging clinical environments.

  6. [Association between self-directed learning behaviors, socio-demographic and academic variables among medical students].

    PubMed

    Fasce H, Eduardo; Ortega B, Javiera; Pérez V, Cristhian; Márquez U, Carolina; Parra P, Paula; Ortiz M, Liliana; Matus, Olga

    2013-09-01

    Medical education must encourage autonomous learning behaviors among students. However the great income profile disparity among university students may influence their capacity to acquire such skills. To assess the association between self-directed learning, socio-demographic and academic variables. The self-directed learning readiness scale was applied to 202 medical students aged between 17 and 25 years (64% males). Simultaneously information about each surveyed participant was obtained from the databases of the medical school. There is an association between socio-demographic and academic variables with the general scale of self-directed learning and the subscales learning planning and willingness to learn. Participants coming from municipal schools have a greater willingness to learn than their counterparts coming from subsidized and private schools. High school grades are related to self-directed learning and the subscales learning planning and self-assessment. Among the surveyed medical students, there is a relationship between self-directed learning behaviors, the type of school where they come from and the grades that they obtained during high school.

  7. Detecting tree-like multicellular life on extrasolar planets.

    PubMed

    Doughty, Christopher E; Wolf, Adam

    2010-11-01

    Over the next two decades, NASA and ESA are planning a series of space-based observatories to find Earth-like planets and determine whether life exists on these planets. Previous studies have assessed the likelihood of detecting life through signs of biogenic gases in the atmosphere or a red edge. Biogenic gases and the red edge could be signs of either single-celled or multicellular life. In this study, we propose a technique with which to determine whether tree-like multicellular life exists on extrasolar planets. For multicellular photosynthetic organisms on Earth, competition for light and the need to transport water and nutrients has led to a tree-like body plan characterized by hierarchical branching networks. This design results in a distinct bidirectional reflectance distribution function (BRDF) that causes differing reflectance at different sun/view geometries. BRDF arises from the changing visibility of the shadows cast by objects, and the presence of tree-like structures is clearly distinguishable from flat ground with the same reflectance spectrum. We examined whether the BRDF could detect the existence of tree-like structures on an extrasolar planet by using changes in planetary albedo as a planet orbits its star. We used a semi-empirical BRDF model to simulate vegetation reflectance at different planetary phase angles and both simulated and real cloud cover to calculate disk and rotation-averaged planetary albedo for a vegetated and non-vegetated planet with abundant liquid water. We found that even if the entire planetary albedo were rendered to a single pixel, the rate of increase of albedo as a planet approaches full illumination would be comparatively greater on a vegetated planet than on a non-vegetated planet. Depending on how accurately planetary cloud cover can be resolved and the capabilities of the coronagraph to resolve exoplanets, this technique could theoretically detect tree-like multicellular life on exoplanets in 50 stellar systems.

  8. Mechanical Control of Cell flow in Multicellular Spheroids

    NASA Astrophysics Data System (ADS)

    Delarue, Morgan; Montel, Fabien; Caen, Ouriel; Elgeti, Jens; Siaugue, Jean-Michel; Vignjevic, Danijela; Prost, Jacques; Joanny, Jean-François; Cappello, Giovanni

    2013-03-01

    Collective cell motion is observed in a wide range of biological processes. In tumors, physiological gradients of nutrients, growth factors, or even oxygen give rise to gradients of proliferation. We show using fluorescently labeled particles that these gradients drive a velocity field resulting in a cellular flow in multicellular spheroids. Under mechanical stress, the cellular flow is drastically reduced. We describe the results with a hydrodynamic model that considers only convection of the particles by the cellular flow.

  9. Multi-cellular, three-dimensional living mammalian tissue

    NASA Technical Reports Server (NTRS)

    Goodwin, Thomas J. (Inventor); Wolf, David A. (Inventor)

    1994-01-01

    The present invention relates to a multicellular, three-dimensional, living mammalian tissue. The tissue is produced by a co-culture process wherein two distinct types of mammalian cells are co-cultured in a rotating bioreactor which is completely filled with culture media and cell attachment substrates. As the size of the tissue assemblies formed on the attachment substrates changes, the rotation of the bioreactor is adjusted accordingly.

  10. Controllability in Hybrid Kinetic Equations Modeling Nonequilibrium Multicellular Systems

    PubMed Central

    Bianca, Carlo

    2013-01-01

    This paper is concerned with the derivation of hybrid kinetic partial integrodifferential equations that can be proposed for the mathematical modeling of multicellular systems subjected to external force fields and characterized by nonconservative interactions. In order to prevent an uncontrolled time evolution of the moments of the solution, a control operator is introduced which is based on the Gaussian thermostat. Specifically, the analysis shows that the moments are solution of a Riccati-type differential equation. PMID:24191137

  11. Quantitative multivariate analysis of dynamic multicellular morphogenic trajectories.

    PubMed

    White, Douglas E; Sylvester, Jonathan B; Levario, Thomas J; Lu, Hang; Streelman, J Todd; McDevitt, Todd C; Kemp, Melissa L

    2015-07-01

    Interrogating fundamental cell biology principles that govern tissue morphogenesis is critical to better understanding of developmental biology and engineering novel multicellular systems. Recently, functional micro-tissues derived from pluripotent embryonic stem cell (ESC) aggregates have provided novel platforms for experimental investigation; however elucidating the factors directing emergent spatial phenotypic patterns remains a significant challenge. Computational modelling techniques offer a unique complementary approach to probe mechanisms regulating morphogenic processes and provide a wealth of spatio-temporal data, but quantitative analysis of simulations and comparison to experimental data is extremely difficult. Quantitative descriptions of spatial phenomena across multiple systems and scales would enable unprecedented comparisons of computational simulations with experimental systems, thereby leveraging the inherent power of computational methods to interrogate the mechanisms governing emergent properties of multicellular biology. To address these challenges, we developed a portable pattern recognition pipeline consisting of: the conversion of cellular images into networks, extraction of novel features via network analysis, and generation of morphogenic trajectories. This novel methodology enabled the quantitative description of morphogenic pattern trajectories that could be compared across diverse systems: computational modelling of multicellular structures, differentiation of stem cell aggregates, and gastrulation of cichlid fish. Moreover, this method identified novel spatio-temporal features associated with different stages of embryo gastrulation, and elucidated a complex paracrine mechanism capable of explaining spatiotemporal pattern kinetic differences in ESC aggregates of different sizes.

  12. The origins of multicellularity: a multi-taxon genome initiative.

    PubMed

    Ruiz-Trillo, Iñaki; Burger, Gertraud; Holland, Peter W H; King, Nicole; Lang, B Franz; Roger, Andrew J; Gray, Michael W

    2007-03-01

    The emergence of multicellular organisms from single-celled ancestors -- which occurred several times, independently in different branches of the eukaryotic tree -- is one of the most profound evolutionary transitions in the history of life. These events not only radically changed the course of life on Earth but also created new challenges, including the need for cooperation and communication between cells, and the division of labor among different cell types. However, the genetic changes that accompanied the several origins of multicellularity remain elusive. Recently, the National Human Genome Research Institute (NHGRI) endorsed a multi-taxon genome-sequencing initiative that aims to gain insights into how multicellularity first evolved. This initiative (which we have termed UNICORN) will generate extensive genomic data from some of the closest extant unicellular relatives of both animals and fungi. Here, we introduce this initiative and the biological questions that underpin it, summarize the rationale guiding the choice of organisms and discuss the anticipated benefits to the broader scientific community.

  13. Photoluminescent carbon nanotubes interrogate the permeability of multicellular tumor spheroids

    PubMed Central

    Shah, Janki; Roxbury, Daniel; Paknejad, Navid; Heller, Daniel A.

    2015-01-01

    Nanomaterials have been extensively investigated for cancer drug delivery and imaging applications. Nanoparticles that show promise in two-dimensional cell culture systems often fail in more complex environments, possibly due to the lack of penetration in dense, three-dimensional structures. Multicellular tumor spheroids are an emerging model system to investigate interactions of nanoparticles with 3D in vitro cell culture environments. Using the intrinsic near-infrared emission of semiconducting carbon nanotubes to optically reconstruct their localization within a three-dimensional volume, we resolved the relative permeability of two different multicellular tumor spheroids. Nanotube photoluminescence revealed that nanotubes rapidly internalized into MCF-7 breast cancer cell-derived spheroids, whereas they exhibited little penetration into spheroids derived from SK-136, a cell line that we developed from murine liver cancer. Characterization of the spheroids by electron microscopy and immunohistochemistry revealed large differences in the extracellular matrix and interstitial spacing, which correlated directly with nanotube penetration. This platform portends a new approach to characterize the permeability of living multicellular environments. PMID:26456974

  14. SKOLAR MD: A Model for Self-Directed, In-Context Continuing Medical Education

    PubMed Central

    Strasberg, Howard R.; Rindfleisch, Thomas C.; Hardy, Steven

    2003-01-01

    INTRODUCTION SKOLAR has implemented a web-based CME program with which physicians can earn AMA Category 1 credit for self-directed learning. METHODS Physicians researched their questions in SKOLAR and applied for CME. Physician auditors reviewed all requests across two phases of the project. A selection rule set was derived from phase one and used in phase two to flag a subset of requests for detailed review. The selection rule set is described. RESULTS In phase one, SKOLAR received 1039 CME applications. Applicants frequently found their answer (94%) and would apply it clinically (93%). A linear regression analysis comparing time awarded to time requested (capped at actual time spent) had R2=0.79. DISCUSSION We believe that hat this self-directed approach to CME is effective and an important complement to traditional CME programs. However, selective audit of self-directed CME requests is necessary to ensure validity of credits awarded. PMID:14728250

  15. Self-directed learning: implications and limitations for undergraduate nursing education.

    PubMed

    Levett-Jones, Tracy L

    2005-07-01

    Self-directed learning (SDL) is an educational concept that has received increasing attention in recent years, particularly in the context of higher education. Whilst the benefits of SDL have been espoused by a number of adult education theorists (Brookfield, S., 1986. Understanding and Facilitating Adult Learning. Jossey-Bass, San Francisco; Houle, C., 1984. Patterns of Learning: New Perspectives on Life-Span Education. Jossey-Bass, San Francisco; Knowles, M., 1998. The Adult Leaner: A Neglected Species, fifth ed., Gulf, Houston; Tough, A., 1979. The Adults Learning Project: A Fresh Approach to Theory and Practice in Adult Learning. Ontario Institute for Studies in Education, Toronto), its introduction into curricula has not always been successful (Nolan, J., Nolan, M., 1997a. Self-directed and student-centred learning in nurse education: 1. British Journal of Nursing 6 (1), 51-55; Nolan, J., Nolan, M., 1997b. Self-directed and student-centred learning in nurse education: 2. British Journal of Nursing 6 (2), 103-107; Slevin, O., Lavery, M., 1991. Self-directed learning and student supervision. Nurse Education Today 11, 368-377). The indiscriminate application of SDL principles and poorly prepared teachers and/or students has at times meant that the introduction of SDL has been resented rather than welcomed (Iwasiw, C., 1987. The role of the teacher in self-directed learning. Nurse Education Today 7, 222-227; Turunen, H., Taskinen, H., Voutilainen, U., Tossavainen, K., Sinkkonen, S., 1997. Nursing and social work students' initial orientation towards their studies. Nurse Education Today 17, 67-71). This paper clarifies and explores these issues by: (a) examining the origins of SDL; (b) discussing the relevance of self-directed learning to Knowles' theory of adult learning and contemporary educational practices such as enquiry based learning and problem based learning; and (c) highlighting the implications and limitations of SDL with regard to adult education in

  16. Self-directed learning competence assessment within different healthcare professionals and amongst students in Italy.

    PubMed

    Cadorin, Lucia; Suter, Nicoletta; Dante, Angelo; Williamson, Swapna Naskar; Devetti, Angie; Palese, Alvisa

    2012-05-01

    In the last few years the significance of life-long learning skills has been greatly realised with regard to adult learning, which is based on self-motivation, engagement in learning and making full use of a person's resources. In this context, it is paramount that healthcare professionals take responsibility for their profession by being innovative, creative and flexible to change in order to facilitate the adaptation process and encourage responsiveness to change. The main principles can be summarized as lifelong learning, which are strictly linked to self-directed learning. The aims of this study were to describe (a) the self-directed learning competence of nurses (registered nurse, RN) and radiologist technicians (RT); (b) the self-directed learning competence of RN and RT students before their graduation. A comparative cross-sectional study approach was adopted; a consecutive sample of RNs and RTs attending continuing education seminars, workshops and other initiatives from 2009 to 2010 were considered for this study. Moreover, all nursing and radiology technicians students about to graduate in the same course and studying in the same region were included. The self-rating scale of self-directed learning (SRSSDL) was used to collect data for the purpose of the study. Eight hundred and forty-seven participants were involved (453 RNs, 141 RTs, 182 RN students and 68 RT students) who obtained an average SRSSDL score of 224.7 (±25.0). RNs and RTs got on average a medium-high score (229.1 ± 22.9 and 219.6 ± 29.2, respectively) and the majority of them (63.8-51.1%) reached a high level of self-directed learning. In order to promote tailored continuing education programs and interprofessional continuing education strategies, and identify the support to offer to healthcare workers according to their needs, educators should be aware of their self-directed learning skills. Therefore, individuals with high competence should adopt different strategies from those who

  17. Transition from one- to two-dimensional development facilitates maintenance of multicellularity

    PubMed Central

    Manjarrez-Casas, Alejandra M.; Bagheri, Homayoun C.

    2016-01-01

    Filamentous organisms represent an example where incomplete separation after cell division underlies the development of multicellular formations. With a view to understanding the evolution of more complex multicellular structures, we explore the transition of multicellular growth from one to two dimensions. We develop a computational model to simulate multicellular development in populations where cells exhibit density-dependent division and death rates. In both the one- and two-dimensional contexts, multicellular formations go through a developmental cycle of growth and subsequent decay. However, the model shows that a transition to a higher dimension increases the size of multicellular formations and facilitates the maintenance of large cell clusters for significantly longer periods of time. We further show that the turnover rate for cell division and death scales with the number of iterations required to reach the stationary multicellular size at equilibrium. Although size and life cycles of multicellular organisms are affected by other environmental and genetic factors, the model presented here evaluates the extent to which the transition of multicellular growth from one to two dimensions contributes to the maintenance of multicellular structures during development. PMID:27703714

  18. A Phenomenological Exploration of Self-Directed Learning among Successful Minority Entrepreneurs

    ERIC Educational Resources Information Center

    Alexander, Nancy Hope

    2013-01-01

    This transcendental, phenomenological study explored the Self-directed learning (SDL) of 10 successful minority entrepreneurs. Two SDL theories serve as lenses for the study, Spear and Mocker's (1984) Organizing Circumstance and Brockett and Heimstra's (1991) Personal Responsibility Orientation model. Five themes emerged from the data:…

  19. Verification of Accurate Technical Insight: A Prerequisite for Self-Directed Surgical Training

    ERIC Educational Resources Information Center

    Hu, Yinin; Kim, Helen; Mahmutovic, Adela; Choi, Joanna; Le, Ivy; Rasmussen, Sara

    2015-01-01

    Simulation-based surgical skills training during preclinical education is a persistent challenge due to time constraints of trainees and instructors alike. Self-directed practice is resource-efficient and flexible; however, insight into technical proficiency among trainees is often lacking. The purpose of this study is to prospectively assess the…

  20. Verification of Accurate Technical Insight: A Prerequisite for Self-Directed Surgical Training

    ERIC Educational Resources Information Center

    Hu, Yinin; Kim, Helen; Mahmutovic, Adela; Choi, Joanna; Le, Ivy; Rasmussen, Sara

    2015-01-01

    Simulation-based surgical skills training during preclinical education is a persistent challenge due to time constraints of trainees and instructors alike. Self-directed practice is resource-efficient and flexible; however, insight into technical proficiency among trainees is often lacking. The purpose of this study is to prospectively assess the…

  1. On the Performance of Self-Directed Learning within the French Continuing Vocational Training System.

    ERIC Educational Resources Information Center

    Dif, M'Hamed

    Continuing vocational training (CVT) was officially introduced and codified in France in 1971 to promote individuals' employability, career development, and job flexibility. Self-directed learning was initially considered among the most important instruments for its implementation in addition to employer-directed CVT. Despite increased and…

  2. Iranian Clinical Nurses’ Activities for Self-Directed Learning: A Qualitative Study

    PubMed Central

    Ghiyasvandian, Shahrzad; Malekian, Morteza; Cheraghi, Mohammad Ali

    2016-01-01

    Background: Clinical nurses need lifelong learning skills for responding to the rapid changes of clinical settings. One of the best strategies for lifelong learning is self-directed learning. The aim of this study was to explore Iranian clinical nurses’ activities for self-directed learning. Methods: In this qualitative study, 23 semi-structured personal interviews were conducted with nineteen clinical nurses working in all four hospitals affiliated to Isfahan Social Security Organization, Isfahan, Iran. Study data were analyzed by using the content analysis approach. The study was conducted from June 2013 to October 2014. Findings: Study participants’ activities for self-directed learning fell into two main categories of striving for knowledge acquisition and striving for skill development. The main theme of the study was ‘Revising personal performance based on intellectual-experiential activities’. Conclusions: Study findings suggest that Iranian clinical nurses continually revise their personal performance by performing self-directed intellectual and experiential activities to acquire expertise. The process of acquiring expertise is a linear process which includes two key steps of knowledge acquisition and knowledge development. In order to acquire and advance their knowledge, nurses perform mental learning activities such as sensory perception, self-evaluation, and suspended judgment step-by-step. Moreover, they develop their skills through doing activities like apprenticeship, masterly performance, and self-regulation. The absolute prerequisite to expertise acquisition is that a nurse needs to follow these two steps in a sequential manner. PMID:26652072

  3. Applying Self-Directed Learning Principles in the Technical Training of a High-Risk Industry.

    ERIC Educational Resources Information Center

    Blackwood, Constance C.

    1994-01-01

    Experience with nuclear power plant workers for whom continuing education is mandated yielded techniques for incorporating self-direction to overcome resistance: educate management, involve workers, know the audience, incorporate feedback in training plans, be consistent, use learning contracts, motivate learners, use alternative methods, build…

  4. Evaluation of the Self-Directed Personal Services Program Operated through Enable.

    ERIC Educational Resources Information Center

    Walker, Pam; And Others

    This report evaluates a self-directed personal service (SDPS) program operated through the larger Enable Program for people with disabilities in Onondaga County, New York. First, it contrasts characteristics of traditional personal assistance services (such as low pay, agency-determined, limited types/levels of support, and program management…

  5. Encouraging Self-Directed Group Learning through an E-Portfolio System

    ERIC Educational Resources Information Center

    Fukuda, Eri; Suzuki, Mitsuko; Hashimoto, Shinichi; Okazak, Hironobu

    2014-01-01

    In this study, the researchers examined how 64 university students engaged in self-directed group learning and used a self-developed e-portfolio system. A sixweek event was held where the students made entries to the e-portfolio individually each week, received feedback from advisors, studied in groups on a voluntary basis, and reflected on their…

  6. A Comparison of Satisfied and Dissatisfied Users of Holland's Self Directed Search (SDS).

    ERIC Educational Resources Information Center

    Collins, Anne M.; Sedlacek, William E.

    The Self-Directed Search for Educational and Vocational Planning (SDS) is a self-scoring, self-administering instrument designed by John L. Holland, author of the Vocational Reference Inventory. Preliminary use of the SDS led to the speculation that some people were very dissatisfied with their results and others were quite pleased. Of the 4,631…

  7. A Multivariate Analysis of the Effects of the Self-Directed Search on High School Girls.

    ERIC Educational Resources Information Center

    Holland, John L.; And Others

    1978-01-01

    Determines how the Self-Directed Search (SDS) achieves its effects. High school girls were assessed before and after treatment for vocational aspirations, knowledge of typology, and information seeking. Nonsignificant findings imply that SDS achieves its effects partly because of its numerous occupational options. Instructional booklets increase…

  8. The Relation of Profile Elevation in the Self-Directed Search to Personality Variables.

    ERIC Educational Resources Information Center

    Fuller, Bret E.; Holland, John L.; Johnston, Joseph A.

    1999-01-01

    The NEO Personality Inventory, Personal Styles Inventory, and Self-Directed Search (SDS) were completed by 319 participants. Higher profile elevation (total score of SDS scales) was associated with higher openness to experience and extraversion and lower depressive personality. Results help interpret high or low SDS profiles. (SK)

  9. Sex Differences, Item Revisions, Validity, and the Self-Directed Search

    ERIC Educational Resources Information Center

    Holland, John L.; And Others

    1976-01-01

    The realistic competency and activity scales of the Self-Directed Search were revised to learn if women's scores on these scales could be increased without reducing their concurrent and construct validity for men and women. Results indicate the revisions increase women's realistic scores, but fail to affect their high point codes. (Author)

  10. A Guide to the Self-Directed Career Program: A Practical and Inexpensive Vocational Guidance System.

    ERIC Educational Resources Information Center

    Holland, John L.; And Others

    This report presents the Self-Directed Career program, an inexpensive program designed to provide vocational guidance to all high school students, college students, and adults who desire it. The report discusses the need for such a program, the costs involved, the materials required, and how to use them. Appendix A provides some of the basic and…

  11. Development of a Supported Self-Directed Learning Approach for Anatomy Education

    ERIC Educational Resources Information Center

    Findlater, Gordon S.; Kristmundsdottir, Fanney; Parson, Simon H.; Gillingwater, Thomas H.

    2012-01-01

    The ability to deliver sufficient core anatomical knowledge and understanding to medical students with limited time and resources remains a major challenge for anatomy educators. Here, we report the results of switching from a primarily didactic method of teaching to supported self-directed learning for students studying anatomy as part of…

  12. Using Self-Directed Video Prompting to Teach Students with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Cannella-Malone, Helen I.; Brooks, David G.; Tullis, Christopher A.

    2013-01-01

    This study examined the effects of self-directed video prompting presented via an iPod Touch on teaching four adolescents with moderate-to-severe intellectual and developmental disabilities two daily living tasks. Students were taught to wash a table using instructor-delivered video prompts. After reaching 80% correct for at least three…

  13. Self-Directed Learning Needs, Patterns, and Outcomes among General Surgeons

    ERIC Educational Resources Information Center

    Gagliardi, Anna R.; Wright, Frances C.; Victor, J. Charles; Brouwers, Melissa C.; Silver, Ivan L.

    2009-01-01

    Introduction: To explore the relationship between self-directed learning (SDL) needs, patterns, barriers, and outcomes among nonacademic general surgeons. Methods: Participants dictated details of SDL episodes associated with cancer patient management from October 2007 to March 2008. Transcripts were coded thematically. Frequencies were calculated…

  14. Stages of Learning during a Self-Directed Stress Management Experience

    ERIC Educational Resources Information Center

    Larson, Karl L.

    2015-01-01

    Purpose: The purpose of the study was to document the stages of learning reflected through student journaling during a self-directed experience in stress management, and the relationship of those stages to a historical model. Methods: College students participating in a full-semester course in stress management theory were required to select a…

  15. The Influence of Item Response Indecision on the Self-Directed Search

    ERIC Educational Resources Information Center

    Sampson, James P., Jr.; Shy, Jonathan D.; Hartley, Sarah Lucas; Reardon, Robert C.; Peterson, Gary W.

    2009-01-01

    Students (N = 247) responded to Self-Directed Search (SDS) per the standard response format and were also instructed to record a question mark (?) for items about which they were uncertain (item response indecision [IRI]). The initial responses of the 114 participants with a (?) were then reversed and a second SDS summary code was obtained and…

  16. Status and trends in the direct support workforce in self-directed supports.

    PubMed

    Bogenschutz, Matthew; Hewitt, Amy; Hall-Lande, Jennifer; LaLiberte, Traci

    2010-10-01

    Self-directed programs that allow individuals with intellectual and developmental disabilities to exercise greater control over their finances have become increasingly common in recent years. At the same time, challenges in the recruitment, retention, and training of direct support workers in the field have grown more acute. In this article, the authors investigate the status of the direct support workforce for people using self-directed supports in 1 Midwestern state, based on the results of a statewide survey of service users. Although additional research is needed, the results of this study suggest that people who use self-directed funding options are satisfied with their ability to direct staffing, though challenges remain. Among these challenges, the presence of higher than expected wages but lower than expected benefits provision compared with traditional services may have serious policy and staff retention ramifications that affect the long-term viability of self-directed funding options. In addition, staff training remains a challenge, with service users in this sample reporting low rates of training beyond a general skill set. Implications of these findings are discussed.

  17. Effects of the Self-Directed Search on High School Students

    ERIC Educational Resources Information Center

    Zener, Thelma Baldwin; Schnuelle, Leslie

    1976-01-01

    This study compares effects on high school students (N=959) of the Self Directed Search (SDS), the Vocational Preference Inventory (VPI), and no treatment. Students taking the SDS or the VPI evaluated the instruments, felt more satisfied with current occupational choices, and considered more occupational alternatives. Differences between the…

  18. Self-Directed Learning Needs, Patterns, and Outcomes among General Surgeons

    ERIC Educational Resources Information Center

    Gagliardi, Anna R.; Wright, Frances C.; Victor, J. Charles; Brouwers, Melissa C.; Silver, Ivan L.

    2009-01-01

    Introduction: To explore the relationship between self-directed learning (SDL) needs, patterns, barriers, and outcomes among nonacademic general surgeons. Methods: Participants dictated details of SDL episodes associated with cancer patient management from October 2007 to March 2008. Transcripts were coded thematically. Frequencies were calculated…

  19. The Design of a Web-Based Course for Self-Directed Learning

    ERIC Educational Resources Information Center

    Liu, Mingzhuo

    2009-01-01

    Purpose: The purpose of this paper is to explore how to design a web-based course in the context of China for self-directed learning from four perspectives--i.e. pedagogical, psychological, social and technological--and also to summarize the design principles for the web-based course. Design/methodology/approach: The paper reviews literature…

  20. e-Portfolios Enhancing Students' Self-Directed Learning: A Systematic Review of Influencing Factors

    ERIC Educational Resources Information Center

    Beckers, Jorrick; Dolmans, Diana; Van Merriënboer, Jeroen

    2016-01-01

    e-Portfolios have become increasingly popular among educators as learning tools. Some research even shows that e-portfolios can be utilised to facilitate the development of skills for self-directed learning. Such skills include self-assessment of performance, formulation of learning goals, and selection of future tasks. However, it is not yet…

  1. The Power of Self-Directed Journals: Being a Temporary "Other" for Learning to Teach

    ERIC Educational Resources Information Center

    Matsumoto, Yumi

    2016-01-01

    This case study investigates how an ESL teacher's activity of self-directed journal writing can facilitate learning and function as a mediational tool for teacher professional development. The participant for this study is a native English speaker who taught an ESL freshman writing course in an American university. Since he had little time to…

  2. Effects of Self-Regulatory Instructional Aids on Self-Directed Study

    ERIC Educational Resources Information Center

    Bednall, Timothy C.; Kehoe, E. James

    2011-01-01

    This study examined the effectiveness of providing instructional support for the self-regulation of a self-directed homework assignment. Across four parallel experiments, university students completed an online module on critical thinking. In Experiment 1, participants who were prompted on a broad spectrum of study strategies showed superior…

  3. An Examination of the Self-Directed Learning Practices of ESL Adult Language Learners

    ERIC Educational Resources Information Center

    Grover, Kendra S.; Miller, Michael T.; Swearingen, Brent; Wood, Nancy

    2014-01-01

    Self-directed learning is one of the preeminent theories in the field of adult education. This study explored how English as a Second Language learners directed their own learning outside of the formal classroom through the use of practices that potentially advance their English language proficiency. Results from a survey of over 400 ESL students…

  4. Self-Directed English Language Learning through Watching English Television Drama in China

    ERIC Educational Resources Information Center

    Wang, Danping

    2012-01-01

    This paper presents a case study of a group of Chinese ESL learners in China, who study English by immersing themselves regularly and rigorously in English television drama. A self-directed learning pedagogy has been developed and discussed, which seems to have signposted an effective and economic way for ESL learners to improve linguistic,…

  5. Self-Directed Learning and Prostate Cancer: A Thematic Analysis of the Experiences of Twelve Patients

    ERIC Educational Resources Information Center

    Rager, Kathleen B.

    2006-01-01

    Although self-directed learning is a common response for many of the 232,090 US men who are diagnosed with prostate cancer each year, very little is known about the nature of the experience for them. Four themes emerged from interviews with 12 prostate cancer patients describing their self-education efforts in regard to their disease. A…

  6. The Effect of Formative Testing and Self-Directed Learning on Mathematics Learning Outcomes

    ERIC Educational Resources Information Center

    Sumantri, Mohamad Syarif; Satriani, Retni

    2016-01-01

    The purpose of this research was to determine the effect of formative testing and self-directed learning on mathematics learning outcomes. The research was conducted at an elementary school in central Jakarta during the 2014/2015 school year. Seventy-two fourth-grade students who were selected using random sampling participated in this study. Data…

  7. Enhancing Self-Directed Learning through a Content Quiz Group Learning Assignment

    ERIC Educational Resources Information Center

    Warburton, Natalie; Volet, Simone

    2013-01-01

    This article presents the findings of an empirical study that examined the learning value of a novel group assessment activity aimed at promoting first-year students' development of basic self-directed learning skills required for university study. A content quiz group learning assignment was designed to enhance students' capacity to ask…

  8. Fostering Postgraduate Student Engagement: Online Resources Supporting Self-Directed Learning in a Diverse Cohort

    ERIC Educational Resources Information Center

    Mello, Luciane V.

    2016-01-01

    The research question for this study was: "Can the provision of online resources help to engage and motivate students to become self-directed learners?" This study presents the results of an action research project to answer this question for a postgraduate module at a research-intensive university in the United Kingdom. The analysis of…

  9. New to Facilitating Self-Directed Learning: The Changing Perceptions of Teachers

    ERIC Educational Resources Information Center

    Lai, Conttia; Gardner, David; Law, Ellie

    2013-01-01

    This paper reports on a study examining the attitudes and perceptions of a group of in-service teachers who are new or relatively new to facilitating self-directed learning (SDL) before and after they taught a course with an integrated SDL component. The study also investigates the impact on those teachers' attitudes of an orientation package…

  10. Edmodo Use to Develop Saudi EFL Students' Self-Directed Learning

    ERIC Educational Resources Information Center

    Khodary, Manal Mohamed

    2017-01-01

    This study aimed at exploring the effect of Edmodo use on developing Saudi English as a Foreign Language (EFL) students' Self-Directed Learning (SDL). It employed a quasi-experimental design that included a one group design. The participants (n = 45) were all fifth level students at Languages and Translation Department, Arar Faculty of Education…

  11. Lifestyle and Learning Habits of Croatian College Students: Self-Directed Learners

    ERIC Educational Resources Information Center

    Roberson, Donald N., Jr.

    2012-01-01

    The purpose of this study was to understand more about the activities and learning habits of Croatian College students through the lens of self-directed learning. This research took place in the National Library of Zagreb University over a two year period. Researchers would ask available students for their opinion on a questionnaire; approximately…

  12. Assessing readiness for self-directed learning within a non-traditional nursing cohort.

    PubMed

    Phillips, Brian N; Turnbull, Beverley J; He, Flora X

    2015-03-01

    Increasing deregulation of the Australian tertiary system has led to changes in entry behaviours anticipated in non-traditional student cohorts. Many nursing students are returning to formal studies later in their lives seeking a career change. Accessibility and flexible study paths make external study increasingly attractive. However external studies require a level of commitment and willingness to develop self-direction and a capacity for resilience. This study sought to elicit the level of self-directed learning readiness (SDLR) among undergraduate nursing students currently enrolled at a bachelor level, and to elicit what differences existed in the levels of SDLR in relation to age, gender, academic year, and previous qualifications. An online survey questionnaire was utilised based on the Self-directed Learning Readiness Scale for Nursing Education. In contrast to earlier work, the participant profile in this study was predominantly non-traditional and captured participants from all three years of the nursing programme. Results found no significant age or gender differences. First year students demonstrated lower levels of self-directed learning readiness. However, unexpected results were demonstrated in the survey subscales in relation to previous qualifications. Participants who already held post-graduate qualifications showed lower scores for Self-Management than those who held diploma qualifications, while students who already held a bachelor's degree had the highest scores in Desire for Learning. The study findings suggest that universities should not assume that SDL capability is dependent on mature age or length of exposure to tertiary study.

  13. Self-Directed Learning and Academic Achievement in Secondary Online Students

    ERIC Educational Resources Information Center

    Carson, Elaine Hendricks

    2012-01-01

    This study examined attributes of self-directed learning (SDL) in students, grades 8 through 12, taking online courses through a state-wide online program in the Southeastern United States. The study investigated whether distinct latent classes of SDL exist; whether there was a significant difference in SDL according to gender, ethnicity, and…

  14. An Investigation of the Construct Validity of the Personality Trait of Self-Directed Learning

    ERIC Educational Resources Information Center

    Lounsbury, John W.; Levy, Levy J.; Park, Soo-Hee; Gibson, Lucy W.; Smith, Ryan

    2009-01-01

    Based on samples of 398 middle school students, 568 high school students, and 1159 college students, self-directed learning was found to be related to cumulative grade-point-average at all levels as well as to Big Five personality traits (Openness, Conscientiousness, Emotional Stability, and Extraversion), narrow personality traits (Optimism,…

  15. Development and Initial Validation of the Self-Directed Learning Inventory with Korean College Students

    ERIC Educational Resources Information Center

    Suh, Han Na; Wang, Kenneth T.; Arterberry, Brooke J.

    2015-01-01

    This article describes the development and psychometric evaluation of the Self-Directed Learning Inventory (SDLI) tailored to Korean college students, based on study evidences of differences in learning behavior across culture and educational level. With a sample of 605 female college students in Korea, exploratory factor analysis (EFA) results…

  16. Self-Directed Learning and Prostate Cancer: A Thematic Analysis of the Experiences of Twelve Patients

    ERIC Educational Resources Information Center

    Rager, Kathleen B.

    2006-01-01

    Although self-directed learning is a common response for many of the 232,090 US men who are diagnosed with prostate cancer each year, very little is known about the nature of the experience for them. Four themes emerged from interviews with 12 prostate cancer patients describing their self-education efforts in regard to their disease. A…

  17. A Thematic Analysis of the Self-Directed Learning Experiences of 13 Breast Cancer Patients

    ERIC Educational Resources Information Center

    Rager, Kathleen

    2004-01-01

    Although self-directed learning is a common response for many of the 183000 American women who are diagnosed with breast cancer each year, very little is known about the nature of the experience for them. Four themes emerged from interviews with 13 breast cancer patients describing their self-education efforts in regard to their disease. A…

  18. The Effect of Self-Directed Work Teams on Work Ethic

    ERIC Educational Resources Information Center

    Petty, Gregory C.; Lim, Doo Hun; Yoon, Seung Won; Fontan, Johnny

    2008-01-01

    This study examined the work ethic of manufacturing machine operators between self-directed work teams and traditional work groups using four work ethic subscales: dependable, considerate, ambitious, and cooperative (Dawson, [1999]; Petty, [1991]). Differences in measured work ethic scores were also compared across six demographic variables: age,…

  19. The Effect of Self-Directed Work Teams on Work Ethic

    ERIC Educational Resources Information Center

    Lim, Doo Hun; Petty, Gregory; Fontan, Johnny; Yoon, Seung Won

    2008-01-01

    The purpose of this study was to compare work ethic of manufacturing machine operators between a self-directed work team and a traditional work team based on four work ethic subscales and identify differences in work ethic based on six demographic factors. The major findings from the study indicated there were significant differences in the work…

  20. Reflective Teaching as Self-Directed Professional Development: Building Practical or Work-Related Knowledge

    ERIC Educational Resources Information Center

    Minott, Mark A.

    2010-01-01

    The broad purpose of this self-study is two-fold: first, to aid in redressing the lack of attention given to the professional development of teacher educators; and second, to forward the idea that teaching reflectively is not only an excellent framework through which self-directed professional development can be enacted, but it is also an…

  1. Individualized Instruction in Science, Time-Space-Matter, Self-Directed Activities.

    ERIC Educational Resources Information Center

    Kuczma, R. M.

    As a supplement to Learning Activity Packages (LAP) on the time-space-matter subject, details are presented for self-directed activities. Major descriptions are given on the background of LAP characteristics, metric system, profile graph construction, spectroscope operation, radiant energy measurement, sunspot effects, density determination,…

  2. An Examination of Self-Directed Learning Readiness in Executive-Level Fire Officers

    ERIC Educational Resources Information Center

    Knight, Steven G.

    2012-01-01

    The purpose of this study was to examine the self-directed learning readiness in executive fire officers in relation to the independent variables of personality type, educational attainment, and professional designation. This research utilized a quantitative design. This study utilized the Myers-Briggs Type Indicator (MBTI) and the Self-Directed…

  3. Development of a Supported Self-Directed Learning Approach for Anatomy Education

    ERIC Educational Resources Information Center

    Findlater, Gordon S.; Kristmundsdottir, Fanney; Parson, Simon H.; Gillingwater, Thomas H.

    2012-01-01

    The ability to deliver sufficient core anatomical knowledge and understanding to medical students with limited time and resources remains a major challenge for anatomy educators. Here, we report the results of switching from a primarily didactic method of teaching to supported self-directed learning for students studying anatomy as part of…

  4. "The Plan(ner) Is Always Changing": Self-Directed Funding for Children with Hearing Loss

    ERIC Educational Resources Information Center

    Simpson, Andrea; Stewart, Lauryn; Douglas, Jacinta

    2016-01-01

    This study investigated the experience of families with young children with hearing loss participating in a self-directed funding scheme in Australia. Eleven hearing caregivers, one male, participated in qualitative semi-structured interviews. Analysis was undertaken using a phenomenological inspired thematic analysis approach. Major themes…

  5. Designing E-Portfolio with ARCS Motivational Design Strategies to Enhance Self-Directed Learning

    ERIC Educational Resources Information Center

    Mohamad, Syamsul Nor Azlan; Embi, Mohamed Amin; Nordin, Norazah Mohd

    2016-01-01

    This paper presents the instructional design effect on motivation towards the implementation of e-Portfolio with ARCS Motivational design strategies to enhance self-directed learning. The purpose of the study was to examine the learners' motivation level after the implementation of e-Portfolio. Initially, this paper was conducted to study a total…

  6. Fostering Postgraduate Student Engagement: Online Resources Supporting Self-Directed Learning in a Diverse Cohort

    ERIC Educational Resources Information Center

    Mello, Luciane V.

    2016-01-01

    The research question for this study was: "Can the provision of online resources help to engage and motivate students to become self-directed learners?" This study presents the results of an action research project to answer this question for a postgraduate module at a research-intensive university in the United Kingdom. The analysis of…

  7. Costs of injuries due to interpersonal and self-directed violence in Thailand, 2005.

    PubMed

    Bundhamcharoen, Kanitta; Odton, Patarapan; Mugem, Suwanna; Phulkerd, Sirinya; Dhisayathikom, Kanjana; Brown, David W; Tangcharoensathien, Viroj

    2008-06-01

    Violence, a serious public health problem in Thailand, remains largely unknown for its economic costs. This study is a national-level economic cost-estimates of injury from interpersonal and self-directed violence for Thailand during 2005 using the World Health Organization-US Centers for Disease Control and Prevention's guidelines. Direct medical costs from self-directed violence totaled 569 million Baht (THB) while the cost of interpersonal violence was THB 1.3 billion. Productivity losses for injuries due to self-directed violence were estimated at THB 12.2 billion and those for interpersonal violence were THB 14.4 billion. The total direct medical cost, thus, accounted for about 4% of Thailand's total health budget while the productivity losses accounted for approximately 0.4% of Thailand s GDP In summary, interpersonal and self-directed violence caused a total loss of 33.8 billion baht for Thailand in 2005. More than 90% of the economic loss was incurred from productivity loss and about four-fifths came from men.

  8. Self-Directed Learning to Develop Autonomy in an Online ESP Community

    ERIC Educational Resources Information Center

    Yang, Yu-Fen

    2016-01-01

    Low foreign language achievers in vocational education often have a lack of learning strategies, a tendency to feel frustrated, and unwillingness to be involved. In order to develop vocational college students' autonomy, this study integrated on-site workshops with an online learning community by means of self-directed learning English for…

  9. Relinquishing Power in the Classroom: A Case Study on Self-Directed Teams in the Classroom.

    ERIC Educational Resources Information Center

    Driskill, Gerald W.; Polansky, Brian

    The shift toward self-directed work teams in organizations is well documented and is further underscored by models that give teamwork an integral role in accomplishing organizational goals. The traditional classroom fails to mirror such shifts when it emphasizes instructor control and decision making with a premium placed on clarity in direction,…

  10. Psychometric Properties of the Chinese Self-Directed Search (1994 Edition)

    ERIC Educational Resources Information Center

    Yang, Weiwei; Lance, Charles E.; Hui, Harry C.

    2006-01-01

    In this study, we (a) examined the measurement equivalence/invariance (ME/I) of the Chinese Self-Directed Search (SDS; 1994 edition) across gender and geographic regions (Mainland China vs. Hong Kong); (b) assessed the construct validity of the Chinese SDS using Widaman's (1985, 1992) MTMM framework; and (c) determined whether vocational interests…

  11. A Journey with Chronic Pain: Self-Directed Learning as Survival

    ERIC Educational Resources Information Center

    King, Kathleen P.

    2014-01-01

    Over the past 20 years in the USA, increased insurance control of healthcare decisions, litigation and regulations, have contributed to a dramatic shift in the doctor-patient relationship and respective responsibilities. This paper presents an autoethnographic study of the self-directed learning (SDL) strategies and patterns used by an individual…

  12. Promoting Self-Directed Learning in a Learning Organization: Tools and Practices

    ERIC Educational Resources Information Center

    Rana, Sowath; Ardichvili, Alexandre; Polesello, Daiane

    2016-01-01

    Purpose: The purpose of this paper is to examine a set of practices that can help promote self-directed learning (SDL) in congruence with the goals of developing and maintaining a learning organization. Design/methodology/approach Findings from this study were derived from an extensive review of the SDL and the learning organization literature, as…

  13. Twin Similarities in Holland Types as Shown by Scores on the Self-Directed Search

    ERIC Educational Resources Information Center

    Chauvin, Ida; McDaniel, Janelle R.; Miller, Mark J.; King, James M.; Eddlemon, Ondie L. M.

    2012-01-01

    This study examined the degree of similarity between scores on the Self-Directed Search from one set of identical twins. Predictably, a high congruence score was found. Results from a biographical sheet are discussed as well as implications of the results for career counselors.

  14. Interests, Aspirations, Self-Estimates, and the Self-Directed Search.

    ERIC Educational Resources Information Center

    Gottfredson, Gary D.

    2002-01-01

    Self-beliefs are not measures of ability and skill but they are correlated with interests and activities and are useful predictors of occupational choices. Holland's theory of vocational personalities provides a framework compatible with Social Cognitive Career Theory and goal theory; the Self-Directed Search is a viable means of assessing…

  15. Predictors of Self-Directed Learning for Low-Qualified Employees: A Multi-Level Analysis

    ERIC Educational Resources Information Center

    Raemdonck, Isabel; van der Leeden, Rien; Valcke, Martin; Segers, Mien; Thijssen, Jo

    2012-01-01

    Purpose: This study aims to examine which variables at the level of the individual employee and at the company level are predictors of self-directed learning in low-qualified employees. Methodology: Results were obtained from a sample of 408 low-qualified employees from 35 different companies. The companies were selected from the energy sector,…

  16. Self-Directed Learning: Adult Learners' Perceptions and Their Study Materials.

    ERIC Educational Resources Information Center

    Greyling, E. S. G.; Geyser, H. C.; Fourie, C. M.

    2002-01-01

    Triggered by the poor performance of historically-disadvantaged students in a South African distance education course, examined students' perceptions of their self-directed learning (SDL). Also examined the SDL support contained in their study materials. Found that the students generally lacked readiness for SDL, suggesting several changes needed…

  17. Supporting Students to Self-Direct Intentional Learning Projects with Social Media

    ERIC Educational Resources Information Center

    Valjataga, Terje; Fiedler, Sebastian

    2009-01-01

    In order to be able to cope with many authentic challenges in increasingly networked and technologically mediated life we need to construct opportunities for participants in higher educational settings to practice the advancement of self-directing intentional learning projects. In addition to teaching general strategies for carrying out these…

  18. The Influence of Job Characteristics and Self-Directed Learning Orientation on Workplace Learning

    ERIC Educational Resources Information Center

    Raemdonck, Isabel; Gijbels, David; van Groen, Willemijn

    2014-01-01

    Given the increasing importance of learning at work, we set out to examine the factors which influence workplace learning behaviour. The study investigated the influence of the job characteristics from Karasek's Job Demand Control Support model and the personal characteristic self-directed learning orientation on workplace learning. A total…

  19. Twin Similarities in Holland Types as Shown by Scores on the Self-Directed Search

    ERIC Educational Resources Information Center

    Chauvin, Ida; McDaniel, Janelle R.; Miller, Mark J.; King, James M.; Eddlemon, Ondie L. M.

    2012-01-01

    This study examined the degree of similarity between scores on the Self-Directed Search from one set of identical twins. Predictably, a high congruence score was found. Results from a biographical sheet are discussed as well as implications of the results for career counselors.

  20. Asking Questions during Self-Directed Inductive Learning: Effects on Learning Outcome and Learning Processes

    ERIC Educational Resources Information Center

    Wilhelm, Pascal; Beishuizen, Jos J.

    2004-01-01

    Asking learners standardized questions during performance of a self-directed inductive learning task might be a useful way to complement think aloud protocol data. However, asking questions might also scaffold the learning process and thus influence the exact processes one wants to study. In the study described in this paper two groups of learners…

  1. Motivations, Achievements, and Challenges of Self-Directed Informal Learners in Open Educational Environments and MOOCs

    ERIC Educational Resources Information Center

    Bonk, Curtis J.; Lee, Mimi Miyoung

    2017-01-01

    This research targeted the learning preferences, goals and motivations, achievements, challenges, and possibilities for life change of self-directed online learners enrolled in a massive open online course (MOOC) related to online teaching hosted by Blackboard using CourseSites. Data collection included a 40-item survey, of which 159 MOOC…

  2. Individually Guided Motivation: Goal-Setting Procedures to Develop Student Self-Direction and Prosocial Behaviors.

    ERIC Educational Resources Information Center

    Klausmeier, Herbert J.; And Others

    This paper describes research and development activities dealing with a system of individually guided motivation at a Wisconsin elementary school. Four general objectives for the project are stated. These deal with motivation for learning subject matter knowledge and skills, developing independence, assuming increasing self direction, and…

  3. Reflective Teaching as Self-Directed Professional Development: Building Practical or Work-Related Knowledge

    ERIC Educational Resources Information Center

    Minott, Mark A.

    2010-01-01

    The broad purpose of this self-study is two-fold: first, to aid in redressing the lack of attention given to the professional development of teacher educators; and second, to forward the idea that teaching reflectively is not only an excellent framework through which self-directed professional development can be enacted, but it is also an…

  4. Self-Directed Learning to Develop Autonomy in an Online ESP Community

    ERIC Educational Resources Information Center

    Yang, Yu-Fen

    2016-01-01

    Low foreign language achievers in vocational education often have a lack of learning strategies, a tendency to feel frustrated, and unwillingness to be involved. In order to develop vocational college students' autonomy, this study integrated on-site workshops with an online learning community by means of self-directed learning English for…

  5. Resistance by Educators to Using a Self-Directed Learning Perception Scale.

    ERIC Educational Resources Information Center

    Pilling-Cormick, Jane

    1994-01-01

    Educator resistance to using a self-directed learning (SDL) scale stems from such myths as the following: SDL implies change, threatens the teacher role, is a test of teacher performance, and cannot be measured. Resistance can be overcome by researching teacher backgrounds, acknowledging the right to resist, explaining intentions, and outlining…

  6. Psychometric Properties of the Chinese Self-Directed Search (1994 Edition)

    ERIC Educational Resources Information Center

    Yang, Weiwei; Lance, Charles E.; Hui, Harry C.

    2006-01-01

    In this study, we (a) examined the measurement equivalence/invariance (ME/I) of the Chinese Self-Directed Search (SDS; 1994 edition) across gender and geographic regions (Mainland China vs. Hong Kong); (b) assessed the construct validity of the Chinese SDS using Widaman's (1985, 1992) MTMM framework; and (c) determined whether vocational interests…

  7. An Exploratory Study of Self-Directed Science Concept Learning by Students with Moderate Intellectual Disabilities

    ERIC Educational Resources Information Center

    Jimenez, Bree A.; Browder, Diane M.; Courtade, Ginevra R.

    2009-01-01

    This investigation focused on the effects of a treatment package including multiple exemplar training, time delay, and a self-directed learning prompt (KWHL chart) on students' ability to complete an inquiry lesson independently and generalize to untrained materials. Three middle school students with moderate intellectual disabilities learned to…

  8. Developmental Aspects of Adult Education: A Comparison of Traditional and Nontraditional Self-Directed Learning Programs.

    ERIC Educational Resources Information Center

    Billington, Dorothy D.

    1990-01-01

    Men and women (N=60) who had begun doctoral studies between ages of 37 and 48, half in traditional and half in self-directed learning (SDL) programs, completed 2 questionnaires. Significant ego development was found in the nonauthoritarian SDL environments, which were challenging and nurturing and fostered content mastery, skill acquisition, and…

  9. Student Perspectives of Self-Directed Language Learning: Implications for Teaching and Research

    ERIC Educational Resources Information Center

    Du, Fengning

    2013-01-01

    This article presents findings from a qualitative study examining students' perspectives of engaging in an autonomous learning project at a community college. Through the conceptual prism of self-directed learning, this study describes how students view the benefits of SDL as well as the roles of teachers. It also touches on factors contributing…

  10. Determining a Difference in Self-Directed Learning Readiness Using the Survey of Adult Learning Traits

    ERIC Educational Resources Information Center

    Ezell, Diana

    2013-01-01

    The purpose of this study was to measure the self-directed learning of educators and explore the differences between and among the variables of age, level of education, position, school district ratings, levels of poverty and affluence, and gender. The Survey of Adult Learning Traits (SALT) authored by Hogg was used as the instrument to measure…

  11. Individualized Instruction in Science, Earth-Space Project, Self-Directed Activities.

    ERIC Educational Resources Information Center

    Kuczma, R. M.

    As a supplement to Learning Activity Packages (LAP) of the earth-space project, this manual presents self-directed activities especially designed for individualized instruction. Besides an introduction to LAP characteristics, sets of instructions are given in connection with the metric system, the earth's dimensions, indirect evidence for atomic…

  12. The Relationship between Self-Directed Learning Readiness and Student Retention in Nursing Education

    ERIC Educational Resources Information Center

    Larmon, Brandy H.

    2015-01-01

    Retention in higher education, especially nursing education, is a concern for nurse educators. Due to the needs of nurse graduates and practicing nurses, the characteristic of self-directed learning in students is often an educational goal of a rigorous nursing curriculum. Program retention is often impacted by such demands. This study, based upon…

  13. The Power of Self-Directed Journals: Being a Temporary "Other" for Learning to Teach

    ERIC Educational Resources Information Center

    Matsumoto, Yumi

    2016-01-01

    This case study investigates how an ESL teacher's activity of self-directed journal writing can facilitate learning and function as a mediational tool for teacher professional development. The participant for this study is a native English speaker who taught an ESL freshman writing course in an American university. Since he had little time to…

  14. Personalisation of Adult Social Care: Self-Directed Support and the Choice and Control Agenda

    ERIC Educational Resources Information Center

    Kendall, Sophie; Cameron, Ailsa

    2014-01-01

    In 2007, "self-directed support" was introduced in adult social care in England to establish choice and control--in the assessment process itself and over service provision--for "all" service users. The personalisation agenda is underpinned by a range of ideologies, particularly a civil rights empowerment approach and…

  15. The Self-Directed Learning Experience of Mothers Whose Child Has Had a Paediatric Stroke

    ERIC Educational Resources Information Center

    Grover, Kenda S.

    2014-01-01

    This study employed qualitative research methodology to explore the experiences of mothers who self-directed their learning following their child's stroke diagnosis. Paediatric stroke, although rare, is among the top 10 causes of death in children in the USA, but information about the cause, treatment and long-term impact are difficult to…

  16. "The Plan(ner) Is Always Changing": Self-Directed Funding for Children with Hearing Loss

    ERIC Educational Resources Information Center

    Simpson, Andrea; Stewart, Lauryn; Douglas, Jacinta

    2016-01-01

    This study investigated the experience of families with young children with hearing loss participating in a self-directed funding scheme in Australia. Eleven hearing caregivers, one male, participated in qualitative semi-structured interviews. Analysis was undertaken using a phenomenological inspired thematic analysis approach. Major themes…

  17. Design and Evaluation of a Development Portfolio: How to Improve Students' Self-Directed Learning Skills

    ERIC Educational Resources Information Center

    Kicken, Wendy; Brand-Gruwel, Saskia; van Merrienboer, Jeroen; Slot, Wim

    2009-01-01

    In on-demand education, students often experience problems with directing their own learning processes. A Structured Task Evaluation and Planning Portfolio (STEPP) was designed to help students develop 3 basic self-directed learning skills: Assessing the quality of own performance, formulating learning needs, and selecting future learning tasks. A…

  18. Understanding Responsibility: A Self-Directed Learning Application of the Triangle Model of Responsibility

    ERIC Educational Resources Information Center

    Kohns, Jonathan W.; Ponton, Michael K.

    2006-01-01

    Personal responsibility has long been considered an important component in self-directed learning. And yet, a theoretical understanding of personal responsibility that could lead to meaningful instrumentation has eluded the field. The present study considers the merits of the Triangle Model of Responsibility (TMR) (Schlenker, Britt, Pennington,…

  19. The Effect of Self-Directed Work Teams on Work Ethic

    ERIC Educational Resources Information Center

    Petty, Gregory C.; Lim, Doo Hun; Yoon, Seung Won; Fontan, Johnny

    2008-01-01

    This study examined the work ethic of manufacturing machine operators between self-directed work teams and traditional work groups using four work ethic subscales: dependable, considerate, ambitious, and cooperative (Dawson, [1999]; Petty, [1991]). Differences in measured work ethic scores were also compared across six demographic variables: age,…

  20. Conquering internal process problems with the use of cross-functional self-directed work teams.

    PubMed

    Sly, C F

    1997-05-01

    The purpose of this article is to introduce a no-nonsense approach to motivating employees while reducing cycle time, improving quality, and creating a flexibly trained, self-directed work force. The article focuses on both the use of cross-functional teams and the change in the role of management that must occur.

  1. An Examination of Self-Directed Learning Readiness in Executive-Level Fire Officers

    ERIC Educational Resources Information Center

    Knight, Steven G.

    2012-01-01

    The purpose of this study was to examine the self-directed learning readiness in executive fire officers in relation to the independent variables of personality type, educational attainment, and professional designation. This research utilized a quantitative design. This study utilized the Myers-Briggs Type Indicator (MBTI) and the Self-Directed…

  2. Design and Evaluation of a Development Portfolio: How to Improve Students' Self-Directed Learning Skills

    ERIC Educational Resources Information Center

    Kicken, Wendy; Brand-Gruwel, Saskia; van Merrienboer, Jeroen; Slot, Wim

    2009-01-01

    In on-demand education, students often experience problems with directing their own learning processes. A Structured Task Evaluation and Planning Portfolio (STEPP) was designed to help students develop 3 basic self-directed learning skills: Assessing the quality of own performance, formulating learning needs, and selecting future learning tasks. A…

  3. Developing and Piloting an App for Managing Self-Directed Language Learning: An Action Research Approach

    ERIC Educational Resources Information Center

    Lammons, Elizabeth; Momata, Yuko; Mynard, Jo; Noguchi, Junko; Watkins, Satoko

    2015-01-01

    Paper-based tools such as self-evaluation activities, learning plans, reflective journals and learning logs are commonplace for managing Self-Directed Language Learning (SDLL). Such tools not only promote ownership over learning and provide a sense of achievement to learners, but they also promote reflection and raise awareness of learning…

  4. A Journey with Chronic Pain: Self-Directed Learning as Survival

    ERIC Educational Resources Information Center

    King, Kathleen P.

    2014-01-01

    Over the past 20 years in the USA, increased insurance control of healthcare decisions, litigation and regulations, have contributed to a dramatic shift in the doctor-patient relationship and respective responsibilities. This paper presents an autoethnographic study of the self-directed learning (SDL) strategies and patterns used by an individual…

  5. Congruency between Occupational Daydreams and Self Directed Search (SDS) Scores among College Students

    ERIC Educational Resources Information Center

    Miller, Mark J.; Springer, Thomas P.; Tobacyk, Jerome; Wells, Don

    2004-01-01

    In this study, the relationship of expressed occupational daydreams and scores on the Self-Directed Search (SDS) were examined. Results were consistent with Holland's theory of careers. Implications for career counselors are discussed. Students were asked to provide specific biographical data (i. e., age, gender, race) and to write down their…

  6. Serious but Fun, Self-Directed yet Social: Blogging as a Form of Lifelong Learning

    ERIC Educational Resources Information Center

    Harju, Vilhelmiina; Pehkonen, Leila; Niemi, Hannele

    2016-01-01

    The article explores the role of digital media in supporting lifelong learning. In particular, it focuses on bloggers who write their blogs voluntarily in their own free time. The aim is to examine how lifelong learning--viewed as self-directed, nonformal learning and active participation that evolves from a desire for self-actualization--occurs…

  7. Students' Perceptions of Self-Directed Learning and Collaborative Learning with and without Technology

    ERIC Educational Resources Information Center

    Lee, K.; Tsai, P.-S.; Chai, C. S.; Koh, J. H. L.

    2014-01-01

    This study explored students' perceptions of self-directed learning (SDL) and collaborative learning (CL) with/without technology in an information and communications technology-supported classroom environment. The factors include SDL, CL, SDL supported by technology, and CL supported by technology. Based on the literature review, this study…

  8. The Relationship between Self-Directed Learning Readiness and Student Retention in Nursing Education

    ERIC Educational Resources Information Center

    Larmon, Brandy H.

    2015-01-01

    Retention in higher education, especially nursing education, is a concern for nurse educators. Due to the needs of nurse graduates and practicing nurses, the characteristic of self-directed learning in students is often an educational goal of a rigorous nursing curriculum. Program retention is often impacted by such demands. This study, based upon…

  9. Evaluating the Effects of Competency-Based Web Learning on Self-Directed Learning Aptitudes

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng

    2007-01-01

    The main aim of the study is to evaluate the impact of the competency-based web learning material (CBWLM) on the self-directed learning aptitude (SDLA) of college students. Specifically, it seeks to investigate, statistically, the changes in SDLAs at different stages of competency-based web learning (CBWL) over an eight-week period. The sample of…

  10. Self-Directed Learning: College Students' Technology Preparedness Change in the Last 10 Years

    ERIC Educational Resources Information Center

    Caravello, Michael J.; Jiménez, Joel R.; Kahl, Lois J.; Brachio, Brian; Morote, Elsa-Sofia

    2015-01-01

    This study compares a sample of approximately 44 first year college students in 2005 and 2015 on Long Island, New York, in their technology preparedness and self-directed instruction. The researchers used a survey instrument including demographic information focused upon students' preparation for classroom technology in high school and college.…

  11. e-Portfolios Enhancing Students' Self-Directed Learning: A Systematic Review of Influencing Factors

    ERIC Educational Resources Information Center

    Beckers, Jorrick; Dolmans, Diana; Van Merriënboer, Jeroen

    2016-01-01

    e-Portfolios have become increasingly popular among educators as learning tools. Some research even shows that e-portfolios can be utilised to facilitate the development of skills for self-directed learning. Such skills include self-assessment of performance, formulation of learning goals, and selection of future tasks. However, it is not yet…

  12. Personalisation of Adult Social Care: Self-Directed Support and the Choice and Control Agenda

    ERIC Educational Resources Information Center

    Kendall, Sophie; Cameron, Ailsa

    2014-01-01

    In 2007, "self-directed support" was introduced in adult social care in England to establish choice and control--in the assessment process itself and over service provision--for "all" service users. The personalisation agenda is underpinned by a range of ideologies, particularly a civil rights empowerment approach and…

  13. Self-Directed English Language Learning through Watching English Television Drama in China

    ERIC Educational Resources Information Center

    Wang, Danping

    2012-01-01

    This paper presents a case study of a group of Chinese ESL learners in China, who study English by immersing themselves regularly and rigorously in English television drama. A self-directed learning pedagogy has been developed and discussed, which seems to have signposted an effective and economic way for ESL learners to improve linguistic,…

  14. Computer versus Counselor Interpretation of Interest Inventories: The Case of the Self-Directed Search.

    ERIC Educational Resources Information Center

    Gati, Itamar; Blumberg, Dani

    1991-01-01

    Examined interpretations of 100 career counselee's responses to Self-Directed Search (SDS). Found that agreement between scales identified as relevant was as high as agreement among counselors, insignificant correlations between counselors' judgments of counselee's degree of interest crystallization and Holland's (1985) measure of consistency, and…

  15. Enhancing Self-Directed Learning through a Content Quiz Group Learning Assignment

    ERIC Educational Resources Information Center

    Warburton, Natalie; Volet, Simone

    2013-01-01

    This article presents the findings of an empirical study that examined the learning value of a novel group assessment activity aimed at promoting first-year students' development of basic self-directed learning skills required for university study. A content quiz group learning assignment was designed to enhance students' capacity to ask…

  16. Interests, Aspirations, Self-Estimates, and the Self-Directed Search.

    ERIC Educational Resources Information Center

    Gottfredson, Gary D.

    2002-01-01

    Self-beliefs are not measures of ability and skill but they are correlated with interests and activities and are useful predictors of occupational choices. Holland's theory of vocational personalities provides a framework compatible with Social Cognitive Career Theory and goal theory; the Self-Directed Search is a viable means of assessing…

  17. Applying Self-Directed Learning Principles in the Technical Training of a High-Risk Industry.

    ERIC Educational Resources Information Center

    Blackwood, Constance C.

    1994-01-01

    Experience with nuclear power plant workers for whom continuing education is mandated yielded techniques for incorporating self-direction to overcome resistance: educate management, involve workers, know the audience, incorporate feedback in training plans, be consistent, use learning contracts, motivate learners, use alternative methods, build…

  18. Effects of the "Self-Directed IEP" on Student Participation in Planning Meetings

    ERIC Educational Resources Information Center

    Arndt, Sandra A.; Konrad, Moira; Test, David W.

    2006-01-01

    Although federal special education legislation and the self-determination movement have promoted and increased students' attendance at their Individualized Education Program (IEP) meetings, students' active involvement in the IEP process remains limited. This study used the "Self-Directed IEP" with five students identified with a variety of…

  19. The Influence of Job Characteristics and Self-Directed Learning Orientation on Workplace Learning

    ERIC Educational Resources Information Center

    Raemdonck, Isabel; Gijbels, David; van Groen, Willemijn

    2014-01-01

    Given the increasing importance of learning at work, we set out to examine the factors which influence workplace learning behaviour. The study investigated the influence of the job characteristics from Karasek's Job Demand Control Support model and the personal characteristic self-directed learning orientation on workplace learning. A total…

  20. Interpreting Self-Directed Search Profiles: Validity of the "Rule of Eight"

    ERIC Educational Resources Information Center

    Glavin, Kevin W.; Savickas, Mark L.

    2011-01-01

    Based on the standard error of measurement, Holland (1985) suggested the "rule of eight" for determining the meaningfulness of differences between two summary scores on the Self Directed Search. The present study empirically examined the rule's validity for practice. The participants were 2397 (1497 females and 900 males) undergraduate…

  1. All eyes on me?! Social anxiety and self-directed perception of eye gaze.

    PubMed

    Schulze, Lars; Lobmaier, Janek S; Arnold, Manuel; Renneberg, Babette

    2013-01-01

    To date, only little is known about the self-directed perception and processing of subtle gaze cues in social anxiety that might however contribute to excessive feelings of being looked at by others. Using a web-based approach, participants (n=174) were asked whether or not briefly (300 ms) presented facial expressions modulated in gaze direction (0°, 2°, 4°, 6°, 8°) and valence (angry, fearful, happy, neutral) were directed at them. The results demonstrate a positive, linear relationship between self-reported social anxiety and stronger self-directed perception of others' gaze directions, particularly for negative (angry, fearful) and neutral expressions. Furthermore, faster responding was found for gaze more clearly directed at socially anxious individuals (0°, 2°, and 4°) suggesting a tendency to avoid direct gaze. In sum, the results illustrate an altered self-directed perception of subtle gaze cues. The possibly amplifying effects of social stress on biased self-directed perception of eye gaze are discussed.

  2. Using Self-Directed Video Prompting to Teach Students with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Cannella-Malone, Helen I.; Brooks, David G.; Tullis, Christopher A.

    2013-01-01

    This study examined the effects of self-directed video prompting presented via an iPod Touch on teaching four adolescents with moderate-to-severe intellectual and developmental disabilities two daily living tasks. Students were taught to wash a table using instructor-delivered video prompts. After reaching 80% correct for at least three…

  3. Serious but Fun, Self-Directed yet Social: Blogging as a Form of Lifelong Learning

    ERIC Educational Resources Information Center

    Harju, Vilhelmiina; Pehkonen, Leila; Niemi, Hannele

    2016-01-01

    The article explores the role of digital media in supporting lifelong learning. In particular, it focuses on bloggers who write their blogs voluntarily in their own free time. The aim is to examine how lifelong learning--viewed as self-directed, nonformal learning and active participation that evolves from a desire for self-actualization--occurs…

  4. Digital Technology Use by the Students and English Teachers and Self-Directed Language Learning

    ERIC Educational Resources Information Center

    Sert, Nehir; Boynuegri, Ebru

    2017-01-01

    The digital era is a new challenge for teachers. While children get acquainted with the digital technology before the age of six, teachers, who have encountered with the digital world at a later time in their lives, struggle with it. Self-directed learning, which is crucial for lifelong learning, can be enhanced by the use technology particularly…

  5. A Note on the Validity of the Self-Directed Search

    ERIC Educational Resources Information Center

    Holland, John L.; Nafziger, Dean H.

    1975-01-01

    The scales of the Self-Directed Search (SDS) correlate with the scales of the Kuder, the Thurstone Temperament Schedule, the Bennett Mechanical Comprehension Test, and the Minnesota Paper Form Board in predictable ways across three small samples of high school students. The results support the validity of the SDS. (Author)

  6. Promoting Self-Directed Learning in a Learning Organization: Tools and Practices

    ERIC Educational Resources Information Center

    Rana, Sowath; Ardichvili, Alexandre; Polesello, Daiane

    2016-01-01

    Purpose: The purpose of this paper is to examine a set of practices that can help promote self-directed learning (SDL) in congruence with the goals of developing and maintaining a learning organization. Design/methodology/approach Findings from this study were derived from an extensive review of the SDL and the learning organization literature, as…

  7. Guideposts to Self-Directed Learning. Expert Commentary on Essential Concepts.

    ERIC Educational Resources Information Center

    Confessore, Gary J., Ed.; Confessore, Sharon J., Ed.

    The 15 chapters in this book include commentaries on 12 seminal works on self-directed learning (SDL) by Houle, Knowles, Tough, Spear and Mocker, Brookfield, Caffarella and O'Donnell, and Long et al. These works were identified by a Delphi panel of 49 experts. Chapter titles and authors are as follows: "An Introduction to the Study of…

  8. Promoting Students' Self-Directed Learning Ability through Teaching Mathematics for Social Justice

    ERIC Educational Resources Information Center

    Voss, Richard; Rickards, Tony

    2016-01-01

    Mathematics is a subject which is often taught using abstract methods and processes. These methods by their very nature may for students alienate the relationship between Mathematics and real life situations. Further, these abstract methods and processes may disenfranchise students from becoming self-directed learners of Mathematics. A solution to…

  9. How Older Rural Adults Utilize Self-Directed Learning in Late Life Adjustments

    ERIC Educational Resources Information Center

    Roberson, Donald N., Jr.

    2003-01-01

    The increasing numbers and influence of older adults is causing many segments of western society to re-evaluate the concept of old age. Medical advances and personal lifestyles have resulted in older adults living longer and healthier lives. As one ages, adjustments in work, family, and health must be made. Self-directed learning (SDL) is one way…

  10. The Relative Influence of Different Domains of Social Connectedness on Self-Directed Violence in Adolescence

    ERIC Educational Resources Information Center

    Kaminski, Jennifer W.; Puddy, Richard W.; Hall, Diane M.; Cashman, Sandra Y.; Crosby, Alexander E.; Ortega, LaVonne A. G.

    2010-01-01

    Previous research has linked greater social connectedness with a lowered risk of self-directed violence among adolescents. However, few studies have analyzed the comparative strength of different domains of connectedness (e.g., family, peers and school) to determine where limited resources might best be focused. Data to address that gap were taken…

  11. The Design of a Web-Based Course for Self-Directed Learning

    ERIC Educational Resources Information Center

    Liu, Mingzhuo

    2009-01-01

    Purpose: The purpose of this paper is to explore how to design a web-based course in the context of China for self-directed learning from four perspectives--i.e. pedagogical, psychological, social and technological--and also to summarize the design principles for the web-based course. Design/methodology/approach: The paper reviews literature…

  12. A Phenomenological Exploration of Self-Directed Learning among Successful Minority Entrepreneurs

    ERIC Educational Resources Information Center

    Alexander, Nancy Hope

    2013-01-01

    This transcendental, phenomenological study explored the Self-directed learning (SDL) of 10 successful minority entrepreneurs. Two SDL theories serve as lenses for the study, Spear and Mocker's (1984) Organizing Circumstance and Brockett and Heimstra's (1991) Personal Responsibility Orientation model. Five themes emerged from the data:…

  13. Developing Self-Directed Executive Functioning: Recent Findings and Future Directions

    ERIC Educational Resources Information Center

    Barker, Jane E.; Munakata, Yuko

    2015-01-01

    How do children become increasingly self-directed across development, achieving their goals without help from others? How might such developments be impacted by societal changes in how children spend their time? Children's abilities to achieve their goals are supported by developing executive functions (EFs), cognitive processes that predict…

  14. Retention and Transfer of Children's Self-Directed Critical Thinking Skills.

    ERIC Educational Resources Information Center

    Riesenmy, Madonna R.; And Others

    1991-01-01

    Fourth and fifth graders (n=38) were trained in four thinking roles (task definer, strategist, monitor, and challenger) through small-group discussions to determine whether they retained and transferred their self-directed critical thinking skills. They applied the thinking roles effectively in comparison to untrained children up to eight weeks…

  15. Dynamic Training Elements in a Circuit Theory Course to Implement a Self-Directed Learning Process

    ERIC Educational Resources Information Center

    Krouk, B. I.; Zhuravleva, O. B.

    2009-01-01

    This paper reports on the implementation of a self-directed learning process in a circuit theory course, incorporating dynamic training elements which were designed on the basis of a cybernetic model of cognitive process management. These elements are centrally linked in a dynamic learning frame, created on the monitor screen, which displays the…

  16. The Self-Directed Learning Experience of Mothers Whose Child Has Had a Paediatric Stroke

    ERIC Educational Resources Information Center

    Grover, Kenda S.

    2014-01-01

    This study employed qualitative research methodology to explore the experiences of mothers who self-directed their learning following their child's stroke diagnosis. Paediatric stroke, although rare, is among the top 10 causes of death in children in the USA, but information about the cause, treatment and long-term impact are difficult to…

  17. The Influence of Item Response Indecision on the Self-Directed Search

    ERIC Educational Resources Information Center

    Sampson, James P., Jr.; Shy, Jonathan D.; Hartley, Sarah Lucas; Reardon, Robert C.; Peterson, Gary W.

    2009-01-01

    Students (N = 247) responded to Self-Directed Search (SDS) per the standard response format and were also instructed to record a question mark (?) for items about which they were uncertain (item response indecision [IRI]). The initial responses of the 114 participants with a (?) were then reversed and a second SDS summary code was obtained and…

  18. Predictors of Self-Directed Learning for Low-Qualified Employees: A Multi-Level Analysis

    ERIC Educational Resources Information Center

    Raemdonck, Isabel; van der Leeden, Rien; Valcke, Martin; Segers, Mien; Thijssen, Jo

    2012-01-01

    Purpose: This study aims to examine which variables at the level of the individual employee and at the company level are predictors of self-directed learning in low-qualified employees. Methodology: Results were obtained from a sample of 408 low-qualified employees from 35 different companies. The companies were selected from the energy sector,…

  19. Enculturating Self-Directed Learners through a Facilitated Seamless Learning Process Framework

    ERIC Educational Resources Information Center

    Wong, Lung-Hsiang

    2013-01-01

    The proliferation of mobile technology has opened up or enhanced opportunities for more personalised, self-directed learning experiences beyond the four walls of classrooms. This paper reports an attempt to rise above the past five years' studies on one-to-one mobile seamless learning by foregrounding the notions of facilitated and self-directed…

  20. Using Two Different Self-Directed Search (SDS) Interpretive Materials: Implications for Career Assessment

    ERIC Educational Resources Information Center

    Dozier, V. Casey; Sampson, James P.; Reardon, Robert C.

    2013-01-01

    John Holland's Self-Directed Search (SDS) is a career assessment that consists of several booklets designed to be self-scored and self-administered. It simulates what a practitioner and an individual might do together in a career counseling session (e.g., review preferred activities and occupations; review competencies, abilities and possible…

  1. Force communication in multicellular tissues addressed by laser nanosurgery.

    PubMed

    Colombelli, Julien; Solon, Jérôme

    2013-04-01

    Cell contractility is a prominent mechanism driving multicellular tissue development and remodeling. Forces originated by the actomyosin cytoskeleton not only act within the cell body but can also propagate many layers away from the contraction source and grant tissues the ability to organize collectively and to achieve robust remodeling through development. Tissue tension is being thoroughly investigated in model organisms and increasing evidence is revealing the major role played by the communication, dynamics and propagation of cell-to-cell physical forces in multicellular remodeling. Recently, pulsed-laser-based surgery has fostered in vivo experimental studies to investigate intracellular and supracellular forces in action. The technique offers a unique method to perturb mechanical equilibrium in a subpopulation of cells or in a single cell, while the overall tissue remains intact. In particular, improved ablation precision with short laser pulses and the combination of this technique with biophysical models now allow an in-depth understanding of the role of cellular mechanics in tissue morphogenesis. We first characterize laser ablation modes available to perform intracellular, cellular, or multi-cellular ablation via the example of the model monolayer tissue of the amnioserosa of Drosophila by relating subnanosecond laser pulse energy to ablation efficiency and the probability of cavitation bubble formation. We then review recent laser nanosurgery experiments that have been performed in cultured cells and that tackle actomyosin mechanics and provide molecular insights into force-sensing mechanisms. We finally review studies showing the central role of laser ablation in revealing the nature and orientation of forces involved in intracellular contractility and force mechanosensing in tissue development, e.g., axis elongation, branching morphogenesis, or tissue invagination. We discuss the perspectives offered by the technique in force-based cell

  2. Less-structured time in children's daily lives predicts self-directed executive functioning

    PubMed Central

    Barker, Jane E.; Semenov, Andrei D.; Michaelson, Laura; Provan, Lindsay S.; Snyder, Hannah R.; Munakata, Yuko

    2014-01-01

    Executive functions (EFs) in childhood predict important life outcomes. Thus, there is great interest in attempts to improve EFs early in life. Many interventions are led by trained adults, including structured training activities in the lab, and less-structured activities implemented in schools. Such programs have yielded gains in children's externally-driven executive functioning, where they are instructed on what goal-directed actions to carry out and when. However, it is less clear how children's experiences relate to their development of self-directed executive functioning, where they must determine on their own what goal-directed actions to carry out and when. We hypothesized that time spent in less-structured activities would give children opportunities to practice self-directed executive functioning, and lead to benefits. To investigate this possibility, we collected information from parents about their 6–7 year-old children's daily, annual, and typical schedules. We categorized children's activities as “structured” or “less-structured” based on categorization schemes from prior studies on child leisure time use. We assessed children's self-directed executive functioning using a well-established verbal fluency task, in which children generate members of a category and can decide on their own when to switch from one subcategory to another. The more time that children spent in less-structured activities, the better their self-directed executive functioning. The opposite was true of structured activities, which predicted poorer self-directed executive functioning. These relationships were robust (holding across increasingly strict classifications of structured and less-structured time) and specific (time use did not predict externally-driven executive functioning). We discuss implications, caveats, and ways in which potential interpretations can be distinguished in future work, to advance an understanding of this fundamental aspect of growing up

  3. Less-structured time in children's daily lives predicts self-directed executive functioning.

    PubMed

    Barker, Jane E; Semenov, Andrei D; Michaelson, Laura; Provan, Lindsay S; Snyder, Hannah R; Munakata, Yuko

    2014-01-01

    Executive functions (EFs) in childhood predict important life outcomes. Thus, there is great interest in attempts to improve EFs early in life. Many interventions are led by trained adults, including structured training activities in the lab, and less-structured activities implemented in schools. Such programs have yielded gains in children's externally-driven executive functioning, where they are instructed on what goal-directed actions to carry out and when. However, it is less clear how children's experiences relate to their development of self-directed executive functioning, where they must determine on their own what goal-directed actions to carry out and when. We hypothesized that time spent in less-structured activities would give children opportunities to practice self-directed executive functioning, and lead to benefits. To investigate this possibility, we collected information from parents about their 6-7 year-old children's daily, annual, and typical schedules. We categorized children's activities as "structured" or "less-structured" based on categorization schemes from prior studies on child leisure time use. We assessed children's self-directed executive functioning using a well-established verbal fluency task, in which children generate members of a category and can decide on their own when to switch from one subcategory to another. The more time that children spent in less-structured activities, the better their self-directed executive functioning. The opposite was true of structured activities, which predicted poorer self-directed executive functioning. These relationships were robust (holding across increasingly strict classifications of structured and less-structured time) and specific (time use did not predict externally-driven executive functioning). We discuss implications, caveats, and ways in which potential interpretations can be distinguished in future work, to advance an understanding of this fundamental aspect of growing up.

  4. Exploring first-year undergraduate medical students' self-directed learning readiness to physiology.

    PubMed

    Abraham, Reem Rachel; Fisher, Murray; Kamath, Asha; Izzati, T Aizan; Nabila, Saidatul; Atikah, Nik Nur

    2011-12-01

    Medical students are expected to possess self-directed learning skills to pursue lifelong learning. Previous studies have reported that the readiness for self-directed learning depends on personal attributes as well as the curriculum followed in institutions. Melaka Manipal Medical College of Manipal University (Karnataka, India) offers a Bachelor of Medicine and Bachelor of Surgery (MBBS) twinning program that is of 5 yr in duration. Keeping in mind the amount of time that the curriculum has devoted for self-directed learning, we explored the self-directed learning readiness of first-year MBBS students (n = 130) using a self-directed learning readiness scale (SDLRS) and explored the correlation between SDLRS scores of high achievers, medium achievers, and low achievers with their academic performance in physiology examinations. Students were requested to respond to each item of the SDLRS on a Likert scale. Median scores of the three scales of the SDLRS were compared across the three groups of students using a Kruskall-Wallis test. SDLRS scores of the students (n = 130) were correlated with their marks in theory papers of first, second, and third block-end examinations using Spearmann's correlation coefficient. The mean item score for desire for learning was found to be higher followed by self-control and self-management. Data analyses showed significantly high (P < 0.03) median scores for self-control for high achievers compared with medium and low achievers. Between the groups, high achievers had a higher score for all the three scales of the SDLRS followed by low and medium achievers. SDLRS scores and academic performance of the three groups of students were found to exhibit a weak correlation. This study threw light on the fact that despite having a high desire for learning and ability of self-control, students need to be supported in their self-management skills.

  5. Corelation between Complexity and Stability in Multicellular Organisms

    NASA Astrophysics Data System (ADS)

    Werman, Steven D.; Qaddour, Jihad; Deyoung, Gary; Misra, Prasanta K.

    1997-03-01

    We present a model to study the corelation between the complexity and stability of unicellular and multicellular organisms. We state the postulates made by us and define the thermodynamic functions and other parameters used to formulate the problem. We have also used several theorems based on reasonable assumptions to analyze the functional interactions which are non-symmetric, non-local and non-instantaneous. The mathematical model developed by using these hypotheses is explained in detail and a set of non-linear equations for each type of organism is presented. We present the results obtained by us by solving these equations.

  6. Cellular Potts modeling of complex multicellular behaviors in tissue morphogenesis.

    PubMed

    Hirashima, Tsuyoshi; Rens, Elisabeth G; Merks, Roeland M H

    2017-06-01

    Mathematical modeling is an essential approach for the understanding of complex multicellular behaviors in tissue morphogenesis. Here, we review the cellular Potts model (CPM; also known as the Glazier-Graner-Hogeweg model), an effective computational modeling framework. We discuss its usability for modeling complex developmental phenomena by examining four fundamental examples of tissue morphogenesis: (i) cell sorting, (ii) cyst formation, (iii) tube morphogenesis in kidney development, and (iv) blood vessel formation. The review provides an introduction for biologists for starting simulation analysis using the CPM framework. © 2017 Japanese Society of Developmental Biologists.

  7. Complex Polarity: Building Multicellular Tissues Through Apical Membrane Traffic.

    PubMed

    Román-Fernández, Alvaro; Bryant, David M

    2016-12-01

    The formation of distinct subdomains of the cell surface is crucial for multicellular organism development. The most striking example of this is apical-basal polarization. What is much less appreciated is that underpinning an asymmetric cell surface is an equally dramatic intracellular endosome rearrangement. Here, we review the interplay between classical cell polarity proteins and membrane trafficking pathways, and discuss how this marriage gives rise to cell polarization. We focus on those mechanisms that regulate apical polarization, as this is providing a number of insights into how membrane traffic and polarity are regulated at the tissue level.

  8. Waltzing Volvox/: Orbiting Bound States of Flagellated Multicellular Algae

    NASA Astrophysics Data System (ADS)

    Drescher, K.; Leptos, K.; Pedley, T. J.; Goldstein, R. E.; Ishikawa, T.

    2008-11-01

    The spherical colonial alga Volvox swims by means of flagella on thousands of surface somatic cells. This geometry and its large size makes it a model organism for the fluid dynamics of multicellularity. Remarkably, when two nearby colonies swim close to a solid surface, they are attracted together and can form a stable bound state in which they continuously waltz around each other. A surface-mediated hydrodynamic attraction between colonies combined with the rotational motion of bottom-heavy Volvox are shown to explain the stability and dynamics of the bound state. This phenomenon is suggested to underlie observed clustering of colonies at surfaces.

  9. Experimental evolution of an alternating uni- and multicellular life cycle in Chlamydomonas reinhardtii

    PubMed Central

    Ratcliff, William C.; Herron, Matthew D.; Howell, Kathryn; Pentz, Jennifer T.; Rosenzweig, Frank; Travisano, Michael

    2013-01-01

    The transition to multicellularity enabled the evolution of large, complex organisms, but early steps in this transition remain poorly understood. Here we show that multicellular complexity, including development from a single cell, can evolve rapidly in a unicellular organism that has never had a multicellular ancestor. We subject the alga Chlamydomonas reinhardtii to conditions that favour multicellularity, resulting in the evolution of a multicellular life cycle in which clusters reproduce via motile unicellular propagules. While a single-cell genetic bottleneck during ontogeny is widely regarded as an adaptation to limit among-cell conflict, its appearance very early in this transition suggests that it did not evolve for this purpose. Instead, we find that unicellular propagules are adaptive even in the absence of intercellular conflict, maximizing cluster-level fecundity. These results demonstrate that the unicellular bottleneck, a trait essential for evolving multicellular complexity, can arise rapidly via co-option of the ancestral unicellular form. PMID:24193369

  10. A multicellular 3D heterospheroid model of liver tumor and stromal cells in collagen gel for anti-cancer drug testing.

    PubMed

    Yip, Derek; Cho, Cheul H

    2013-04-12

    Two-dimensional (2D) monolayer cultures are the standard in vitro model for cancer research. However, they fail to recapitulate the three-dimensional (3D) environment and quickly lose their function. In this study, we developed a new 3D multicellular heterospheroid tumor model in a collagen hydrogel culture system that more closely mimics the in vivo tumor microenvironment for anti-cancer drug testing. Three aspects of cancer were chosen to be modeled based on their ability to resist anti-cancer drugs: 3D, multicellularity, and extracellular matrix (ECM) barrier. The hanging drop method and co-culture of liver carcinoma with stromal fibroblasts were used to form controlled and uniform heterospheroids. These heterospheroids were then encapsulated in collagen gel in order to create a 3D model of liver cancer that would act more similarly to in vivo ECM conditions. The 3D heterospheroid tumor model was tested with an anti-cancer drug to determine how each of the above aspects affects drug resistance. The results demonstrate that the 3D heterospheroid model is more resistant to drug over 2D monolayer and homospheroid cultures, indicating stromal fibroblasts and collagen hydrogel culture system provides more resistance to anti-cancer drug. This study will provide useful information toward the development of improved biomimetic tumor models in vitro for cancer research in pre-clinical drug development. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Cancer across the tree of life: cooperation and cheating in multicellularity

    PubMed Central

    Aktipis, C. Athena; Boddy, Amy M.; Jansen, Gunther; Hibner, Urszula; Hochberg, Michael E.; Maley, Carlo C.; Wilkinson, Gerald S.

    2015-01-01

    Multicellularity is characterized by cooperation among cells for the development, maintenance and reproduction of the multicellular organism. Cancer can be viewed as cheating within this cooperative multicellular system. Complex multicellularity, and the cooperation underlying it, has evolved independently multiple times. We review the existing literature on cancer and cancer-like phenomena across life, not only focusing on complex multicellularity but also reviewing cancer-like phenomena across the tree of life more broadly. We find that cancer is characterized by a breakdown of the central features of cooperation that characterize multicellularity, including cheating in proliferation inhibition, cell death, division of labour, resource allocation and extracellular environment maintenance (which we term the five foundations of multicellularity). Cheating on division of labour, exhibited by a lack of differentiation and disorganized cell masses, has been observed in all forms of multicellularity. This suggests that deregulation of differentiation is a fundamental and universal aspect of carcinogenesis that may be underappreciated in cancer biology. Understanding cancer as a breakdown of multicellular cooperation provides novel insights into cancer hallmarks and suggests a set of assays and biomarkers that can be applied across species and characterize the fundamental requirements for generating a cancer. PMID:26056363

  12. Innovation and constraint leading to complex multicellularity in the Ascomycota

    PubMed Central

    Nguyen, Tu Anh; Cissé, Ousmane H.; Yun Wong, Jie; Zheng, Peng; Hewitt, David; Nowrousian, Minou; Stajich, Jason E.; Jedd, Gregory

    2017-01-01

    The advent of complex multicellularity (CM) was a pivotal event in the evolution of animals, plants and fungi. In the fungal Ascomycota, CM is based on hyphal filaments and arose in the Pezizomycotina. The genus Neolecta defines an enigma: phylogenetically placed in a related group containing mostly yeasts, Neolecta nevertheless possesses Pezizomycotina-like CM. Here we sequence the Neolecta irregularis genome and identify CM-associated functions by searching for genes conserved in Neolecta and the Pezizomycotina, which are absent or divergent in budding or fission yeasts. This group of 1,050 genes is enriched for functions related to diverse endomembrane systems and their organization. Remarkably, most show evidence for divergence in both yeasts. Using functional genomics, we identify new genes involved in fungal complexification. Together, these data show that rudimentary multicellularity is deeply rooted in the Ascomycota. Extensive parallel gene divergence during simplification and constraint leading to CM suggest a deterministic process where shared modes of cellular organization select for similarly configured organelle- and transport-related machineries. PMID:28176784

  13. The multicellular nature of filamentous heterocyst-forming cyanobacteria.

    PubMed

    Herrero, Antonia; Stavans, Joel; Flores, Enrique

    2016-11-01

    Cyanobacteria carry out oxygenic photosynthesis, play a key role in the cycling of carbon and nitrogen in the biosphere, and have had a large impact on the evolution of life and the Earth itself. Many cyanobacterial strains exhibit a multicellular lifestyle, growing as filaments that can be hundreds of cells long and endowed with intercellular communication. Furthermore, under depletion of combined nitrogen, filament growth requires the activity of two interdependent cell types: vegetative cells that fix CO2 and heterocysts that fix N2. Intercellular molecular transfer is essential for signaling involved in the regulation of heterocyst differentiation and for reciprocal nutrition of heterocysts and vegetative cells. Here we review various aspects of multicellularity in cyanobacterial filaments and their differentiation, including filament architecture with emphasis on the structures used for intercellular communication; we survey theoretical models that have been put forward to understand heterocyst patterning and discuss the factors that need to be considered for these models to reflect the biological entity; and finally, since cell division in filamentous cyanobacteria has the peculiarity of producing linked instead of independent cells, we review distinct aspects of cell division in these organisms.

  14. Innovation and constraint leading to complex multicellularity in the Ascomycota.

    PubMed

    Nguyen, Tu Anh; Cissé, Ousmane H; Yun Wong, Jie; Zheng, Peng; Hewitt, David; Nowrousian, Minou; Stajich, Jason E; Jedd, Gregory

    2017-02-08

    The advent of complex multicellularity (CM) was a pivotal event in the evolution of animals, plants and fungi. In the fungal Ascomycota, CM is based on hyphal filaments and arose in the Pezizomycotina. The genus Neolecta defines an enigma: phylogenetically placed in a related group containing mostly yeasts, Neolecta nevertheless possesses Pezizomycotina-like CM. Here we sequence the Neolecta irregularis genome and identify CM-associated functions by searching for genes conserved in Neolecta and the Pezizomycotina, which are absent or divergent in budding or fission yeasts. This group of 1,050 genes is enriched for functions related to diverse endomembrane systems and their organization. Remarkably, most show evidence for divergence in both yeasts. Using functional genomics, we identify new genes involved in fungal complexification. Together, these data show that rudimentary multicellularity is deeply rooted in the Ascomycota. Extensive parallel gene divergence during simplification and constraint leading to CM suggest a deterministic process where shared modes of cellular organization select for similarly configured organelle- and transport-related machineries.

  15. Transport by Collective Flagellar Beating Facilitates Evolutionary Transitions to Multicellularity

    NASA Astrophysics Data System (ADS)

    Short, Martin; Powers, Thomas

    2005-11-01

    A central problem underlying the evolution from single cells to multicellular organisms is the relationship between metabolic requirements and environmental metabolite exchange with increasing size. For organisms that form spherical colonies such as the volvocalean green algae, there is a bottleneck if diffusion alone governs nutrient uptake as they increase in size, for the diffusive flux is linear in the radius while the requirements of surface somatic cells grow quadratically. Using Volvox as a model organism, we examine experimentally and theoretically the role that advection of fluid by surface flagella plays in enhancing nutrient uptake. We show that the fluid flow driven by the coordinated beating of those flagella produces a boundary layer in the concentration of a diffusing solute which renders the metabolite exchange rate quadratic in the colony radius. This bypasses the diffusive bottleneck, facilitating evolutionary transitions to multicellularity which may be driven by other environmental factors. These results suggest that flagella may have evolved not only for motility, but also to enhance metabolite exchange.

  16. Modeling of Transmembrane Potential in Realistic Multicellular Structures before Electroporation.

    PubMed

    Murovec, Tomo; Sweeney, Daniel C; Latouche, Eduardo; Davalos, Rafael V; Brosseau, Christian

    2016-11-15

    Many approaches for studying the transmembrane potential (TMP) induced during the treatment of biological cells with pulsed electric fields have been reported. From the simple analytical models to more complex numerical models requiring significant computational resources, a gamut of methods have been used to recapitulate multicellular environments in silico. Cells have been modeled as simple shapes in two dimensions as well as more complex geometries attempting to replicate realistic cell shapes. In this study, we describe a method for extracting realistic cell morphologies from fluorescence microscopy images to generate the piecewise continuous mesh used to develop a finite element model in two dimensions. The preelectroporation TMP induced in tightly packed cells is analyzed for two sets of pulse parameters inspired by clinical irreversible electroporation treatments. We show that high-frequency bipolar pulse trains are better, and more homogeneously raise the TMP of tightly packed cells to a simulated electroporation threshold than conventional irreversible electroporation pulse trains, at the expense of larger applied potentials. Our results demonstrate the viability of our method and emphasize the importance of considering multicellular effects in the numerical models used for studying the response of biological tissues exposed to electric fields. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  17. Self-Directed Learning in Physician Assistant Education: Learning Portfolios in Physician Assistant Programs.

    PubMed

    Neal, Jeremy H; Neal, Laura D M

    2016-12-01

    Self-directed learning (SDL) portfolios are underused in the educational process and should be considered by physician assistant (PA) programs. Clinicians such as PAs are responsible for self-identifying their learning needs, competencies, and ongoing educational requirements. This article introduces an outline for SDL in the PA profession, for direct use by learners and indirect use by educators. Without a plan, many professionals may lack the insight, motivation, and knowledge needed to improve their skill set and establish goals for individual lifelong learning. This study conducted a review of the literature. Then, by incorporating SDL portfolios into PA educational methodologies, it constructed a concept map for individuals to monitor, self-direct, and actively participate in their own learning in academic settings and throughout their career.

  18. Intergroup conflict, out-group derogation, and self-directed negative affect among Italian South Tyroleans.

    PubMed

    Costarelli, Sandro; Colloca, Pasquale

    2004-04-01

    In South Tyrol, a multiethnic Italian province, the authors examined the self-directed negative affect that members of an Italian group experienced after they evaluated members of the German and Albanian groups. The authors examined the affect as a function of out-group derogation. The authors argued that to the extent that out-group derogation may run counter to norms toward intergroup fairness, such normative nonconformity will elicit negative affect directed at the self as a function of perceived intergroup conflict. The findings support the authors' line of reasoning: among Italian South Tyroleans, those who expressed greater out-group derogation were led to experience stronger negative self-directed affect when they rated a low-conflict out-group, but not when they rated a high-conflict out-group, compared to participants whose out-group derogation was less.

  19. Community Reinforcement and Family Training: A Pilot Comparison of Group and Self-Directed Delivery

    PubMed Central

    Manuel, Jennifer K.; Austin, Julia L.; Miller, William R.; McCrady, Barbara S.; Tonigan, J. Scott; Meyers, Robert J.; Smith, Jane Ellen; Bogenschutz, Michael P.

    2011-01-01

    In a randomized clinical pilot study, 40 concerned significant others (CSOs) of treatment-refusing alcohol and drug users were randomized to either CRAFT (Community Reinforcement and Family Training) conducted in a group format (Group CRAFT) or a Self-Directed CRAFT condition. Although results indicated no significant between-group difference in engaging treatment-refusing substance users (referred to as identified patients or IPs) into treatment, the engagement rate in Group CRAFT was similar to rates previously reported with individual CRAFT. For the intent-to-treat analysis, 60% of Group CRAFT CSOs engaged their loved one into treatment, compared to 40% in Self-Directed CRAFT. Of CSOs in the Group condition who received at least one session of group therapy, 71% engaged their IP into treatment. CSOs in both conditions reported improvements in family cohesion and conflict at the three and six-month follow-up, replicating prior CRAFT findings. PMID:22154038

  20. A Preliminary Investigation of Self-Directed Learning Activities in a Non-Formal Blended Learning Environment

    ERIC Educational Resources Information Center

    Schwier, Richard A.; Morrison, Dirk; Daniel, Ben K.

    2009-01-01

    This research considers how professional participants in a non-formal self-directed learning environment (NFSDL) made use of self-directed learning activities in a blended face-to-face and on line learning professional development course. The learning environment for the study was a professional development seminar on teaching in higher education…

  1. The Nature of Self-Directed Learning and Transformational Learning in Self-Managing Bipolar Disorder to Stay Well

    ERIC Educational Resources Information Center

    Francik, Wendy A.

    2012-01-01

    The purpose of the research was to explore the self-directed learning and transformational learning experiences among persons with bipolar disorder. A review of previous research pointed out how personal experiences with self-directed learning and transformational learning facilitated individuals' learning to manage HIV, Methicillan-resitant…

  2. The Relationship between Engineering Students' Self-Directed Learning Abilities and Online Learning Performances: A Pilot Study

    ERIC Educational Resources Information Center

    Chou, Pao-Nan

    2012-01-01

    This study aimed to explore engineering students' self-directed learning abilities in an online learning environment. The research centered on the correlation relationship between students' self-directed learning abilities and learning outcomes. The instructional activity in one experimental study was to simulate an online learning task in the…

  3. Exploring Self-Directed Learning in the Online Learning Environment: Comparing Traditional versus Nontraditional Learner Populations a Qualitative Study

    ERIC Educational Resources Information Center

    Plews, Rachel Christine

    2016-01-01

    The purpose of this study was to explore self-directed learning in the online learning context. A sample of traditional and nontraditional learners, who were considered above average in their level of self-direction, participated in qualitative interviews to discuss their learning while engaged in an online course. The findings suggested no major…

  4. Self-directed learning readiness of Asian students: students perspective on a hybrid problem based learning curriculum.

    PubMed

    Leatemia, Lukas D; Susilo, Astrid P; van Berkel, Henk

    2016-12-03

    To identify the student's readiness to perform self-directed learning and the underlying factors influencing it on the hybrid problem based learning curriculum. A combination of quantitative and qualitative studies was conducted in five medical schools in Indonesia. In the quantitative study, the Self Directed Learning Readiness Scale was distributed to all students in all batches, who had experience with the hybrid problem based curriculum. They were categorized into low- and high -level based on the score of the questionnaire. Three focus group discussions (low-, high-, and mixed level) were conducted in the qualitative study with six to twelve students chosen randomly from each group to find the factors influencing their self-directed learning readiness. Two researchers analysed the qualitative data as a measure of triangulation. The quantitative study showed only half of the students had a high-level of self-directed learning readiness, and a similar trend also occurred in each batch. The proportion of students with a high level of self-directed learning readiness was lower in the senior students compared to more junior students. The qualitative study showed that problem based learning processes, assessments, learning environment, students' life styles, students' perceptions of the topics, and mood, were factors influencing their self-directed learning. A hybrid problem based curriculum may not fully affect the students' self-directed learning. The curriculum system, teacher's experiences, student's background and cultural factors might contribute to the difficulties for the student's in conducting self-directed learning.

  5. Teachers' Self-Directed Professional Development: Science and Mathematics Teachers' Adoption of ICT as a Professional Development Strategy

    ERIC Educational Resources Information Center

    Mushayikwa, Emmanuel

    2013-01-01

    This paper is part of a larger study that was carried out to investigate the use of Information and Communication Technology (ICT) in the self-directed professional development on the self-directed professional development (SDPD) of mathematics and science teachers in Zimbabwe. The educational context provides an example of how teachers…

  6. The intersection of interpersonal and self-directed violence among general adult, college student and sexually diverse samples.

    PubMed

    Cramer, Robert J; Desmarais, Sarah L; Johnson, Kiersten L; Gemberling, Tess M; Nobles, Matt R; Holley, Sarah R; Wright, Susan; Van Dorn, Richard

    2017-02-01

    Suicide and interpersonal violence (i.e. victimization and perpetration) represent pressing public health problems, and yet remain mostly addressed as separate topics. To identify the (1) frequency and overlap of suicide and interpersonal violence and (2) characteristics differentiating subgroups of violence-related experiences. A health survey was completed by 2,175 respondents comprised of three groups: college students ( n = 702), adult members of a sexuality special interest organization ( n = 816) and a community adult sample ( n = 657). Latent class analysis was used to identify subgroups characterized by violence experiences; logistic regression was used to identify respondent characteristics differentiating subgroups. Overall rates of violence perpetration were low; perpetration, victimization and self-directed violence all varied by sample. Adults with alternative sexual interests reported high rates of victimization and self-directed violence. Analyses indicated two subgroups: (1) victimization + self-directed violence and (2) self-directed violence only. The victimization + self-directed violence subgroup was characterized by older, White, female and sexual orientation minority persons. The self-directed violence subgroup was characterized by younger, non-White, male and straight counterparts engaging with more sexual partners and more frequent drug use. Findings support the Centers for Disease Control and Prevention (CDC) definition of suicide as self-directed violence. Suicide intervention and prevention should further account for the role of violent victimization by focusing on the joint conceptualization of self-directed and interpersonal violence. Additional prevention implications are discussed.

  7. Understanding Faculty and Non-Traditional Student Perceptions of Self-Directed Learning in a Practical Nursing Program

    ERIC Educational Resources Information Center

    Rogers, Carmen

    2013-01-01

    This study was designed to identify and investigate nursing faculty and student perspectives of self-directed learning in a practical nursing program. It also explored the degree to which student's perceptions of self-directed learning exhibited factors consistent with that of critical thinking. This study is important because self-directed…

  8. The Nature of Self-Directed Learning and Transformational Learning in Self-Managing Bipolar Disorder to Stay Well

    ERIC Educational Resources Information Center

    Francik, Wendy A.

    2012-01-01

    The purpose of the research was to explore the self-directed learning and transformational learning experiences among persons with bipolar disorder. A review of previous research pointed out how personal experiences with self-directed learning and transformational learning facilitated individuals' learning to manage HIV, Methicillan-resitant…

  9. Exploring Self-Directed Learning in the Online Learning Environment: Comparing Traditional versus Nontraditional Learner Populations a Qualitative Study

    ERIC Educational Resources Information Center

    Plews, Rachel Christine

    2016-01-01

    The purpose of this study was to explore self-directed learning in the online learning context. A sample of traditional and nontraditional learners, who were considered above average in their level of self-direction, participated in qualitative interviews to discuss their learning while engaged in an online course. The findings suggested no major…

  10. The Effects of Case-Based Team Learning on Students’ Learning, Self Regulation and Self Direction

    PubMed Central

    Rezaee, Rita; Mosalanejad, Leili

    2015-01-01

    Introduction: The application of the best approaches to teach adults in medical education is important in the process of training learners to become and remain effective health care providers. This research aims at designing and integrating two approaches, namely team teaching and case study and tries to examine the consequences of these approaches on learning, self regulation and self direction of nursing students. Material & Methods: This is aquasi experimental study of 40 students who were taking a course on mental health. The lessons were designed by using two educational techniques: short case based study and team based learning. Data gathering was based on two valid and reliablequestionnaires: Self-Directed Readiness Scale (SDLRS) and the self-regulating questionnaire. Open ended questions were also designed for the evaluation of students’with points of view on educational methods. Results: The Results showed an increase in the students’ self directed learning based on their performance on the post-test. The results showed that the students’ self-directed learning increased after the intervention. The mean difference before and after intervention self management was statistically significant (p=0.0001). Also, self-regulated learning increased with the mean difference after intervention (p=0.001). Other results suggested that case based team learning can have significant effects on increasing students’ learning (p=0.003). Conclusion: This article may be of value to medical educators who wish to replace traditional learning with informal learning (student-centered-active learning), so as to enhance not only the students’ ’knowledge, but also the advancement of long- life learning skills. PMID:25946918

  11. Clinical nurse preceptor teaching competencies: relationship to locus of control and self-directed learning.

    PubMed

    Chen, Ya-Lin; Hsu, Li-Ling; Hsieh, Suh-Ing

    2012-06-01

    An effective preceptor is a vital component of a strong learning experience for learners. Many clinical preceptors provide on-site supervision and clinical teaching but lack the skills necessary to be effective teachers. Few studies have examined the factors related to teaching competence among clinical nurse preceptors. This article is a report of a study that examined (a) the differences in teaching competence by preceptor background, (b) the influence of locus of control on self-evaluated teaching competence, (c) the association between self-directed learning and self-evaluated teaching competence, and (d) the predictors of self-evaluated teaching competence among clinical nurse preceptors. This descriptive and correlational study used a cross-sectional survey of a convenience sample of 243 clinical nurse preceptors from a medical center in northern Taiwan. Of these, 242 completed questionnaires for an effective response rate of 99.6%. The self-evaluated Teaching Competencies Scale, Internal-External Scale, and Self-Directed Learning Instrument were used to assess teaching competencies and related factors among clinical nurse preceptors. Descriptive statistics, one-way ANOVA, Mann-Whitney test, and multivariate linear regression were used to analyze data. Clinical nurse preceptors averaged 4.03 in teaching competence, indicating a moderately above average score. Higher teaching competence was associated with older age, being married, >10-year work experience, not assigned by unit manager, and good internal locus of control. Self-directed learning significantly correlated with teaching competence (r = .62). Internal locus of control and self-directed learning were significant independent predictors of teaching competence after adjusting for age, marital status, total years as a clinical nurse preceptor, and willingness to be a clinical nurse preceptor. Together, these accounted for 33.6% of teaching competence variance. Nurse managers should recognize all factors

  12. The effects of case-based team learning on students' learning, self regulation and self direction.

    PubMed

    Rezaee, Rita; Mosalanejad, Leili

    2015-01-26

    The application of the best approaches to teach adults in medical education is important in the process of training learners to become and remain effective health care providers. This research aims at designing and integrating two approaches, namely team teaching and case study and tries to examine the consequences of these approaches on learning, self regulation and self direction of nursing students. This is a quasi experimental study of 40 students who were taking a course on mental health. The lessons were designed by using two educational techniques: short case based study and team based learning. Data gathering was based on two valid and reliable questionnaires: Self-Directed Readiness Scale (SDLRS) and the self-regulating questionnaire. Open ended questions were also designed for the evaluation of students' with points of view on educational methods. The Results showed an increase in the students' self directed learning based on their performance on the post-test. The results showed that the students' self-directed learning increased after the intervention. The mean difference before and after intervention self management was statistically significant (p=0.0001). Also, self-regulated learning increased with the mean difference after intervention (p=0.001). Other results suggested that case based team learning can have significant effects on increasing students' learning (p=0.003). This article may be of value to medical educators who wish to replace traditional learning with informal learning (student-centered-active learning), so as to enhance not only the students' knowledge, but also the advancement of long- life learning skills.

  13. Aging and health: Self-efficacy for Self-direction in Health Scale

    PubMed Central

    Oliveira, Albertina L; Silva, José T; Lima, Margarida P

    2016-01-01

    ABSTRACT OBJECTIVE To validate the Escala de Autoeficácia para a Autodireção na Saúde (EAAS – Self-efficacy for Self-direction in Health Scale). METHODS Non-experimental quantitative study of EAAS validation, by confirmatory factorial analyses, evaluating a sample of 508 older adults from the north and the center of Portugal with mean age of 71.67 (from 51 to 96 years), to whom the Self-efficacy for Self-direction in Health Scale, the Rosenberg Self-esteem Scale, the Positive and Negative Affect Schedule, the Satisfaction with Life Scale, and the Instrumental Activities of Daily Living Scale were applied. The EAAS was developed from the theoretical constructs of self-efficacy and from self-directed learning within the PALADIN European project framework, aiming to develop an instrument able to assess the extent to which older adults take good care of their health. RESULTS The internal consistency was 0.87 (Cronbach’s alpha) and confirmatory factorial analyses enabled to find a model near the one theoretically proposed, indicating a structure consisting of four dimensions: physical exercise, healthy diet, engaging in health-related learning, and visits to health professionals. From the psychometric point of view, the model in four factors showed quite satisfactory fit indicators. CONCLUSIONS The Self-efficacy for Self-direction in Health Scale, with 16 items, is adequate to evaluate to what extent older adults have confidence in their ability to take care of their own health, with high degree of autonomy. PMID:27384970

  14. The effect of self-directed virtual reality simulation on dissection training performance in mastoidectomy.

    PubMed

    Andersen, Steven Arild Wuyts; Foghsgaard, Søren; Konge, Lars; Cayé-Thomasen, Per; Sørensen, Mads Sølvsten

    2016-08-01

    To establish the effect of self-directed virtual reality (VR) simulation training on cadaveric dissection training performance in mastoidectomy and the transferability of skills acquired in VR simulation training to the cadaveric dissection training setting. Prospective study. Two cohorts of 20 novice otorhinolaryngology residents received either self-directed VR simulation training before cadaveric dissection training or vice versa. Cadaveric and VR simulation performances were assessed using final-product analysis with three blinded expert raters. The group receiving VR simulation training before cadaveric dissection had a mean final-product score of 14.9 (95 % confidence interval [CI] [12.9-16.9]) compared with 9.8 (95% CI [8.4-11.1]) in the group not receiving VR simulation training before cadaveric dissection. This 52% increase in performance was statistically significantly (P < 0.0001). A single dissection mastoidectomy did not increase VR simulation performance (P = 0.22). Two hours of self-directed VR simulation training was effective in increasing cadaveric dissection mastoidectomy performance and suggests that mastoidectomy skills are transferable from VR simulation to the traditional dissection setting. Virtual reality simulation training can therefore be employed to optimize training, and can spare the use of donated material and instructional resources for more advanced training after basic competencies have been acquired in the VR simulation environment. NA. Laryngoscope, 126:1883-1888, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  15. Are self-directed work teams successful and effective tools for today`s organization?

    SciTech Connect

    Arnwine, A.D.

    1995-03-01

    The purpose of this research is to (1) show the effectiveness and success of self-directed work teams within the organization, (2) emphasize the importance of team building in the success of the team, and (3) assist organizations in building self-directed work teams. The researcher used a direct survey and studied the following team building techniques: (1) Is the team`s mission clearly defined to each team member? (2) Are the goals clearly defined and achievable by all team members? (3) Will empowerment (decision-making power) be given equally to all team members? (4) Will open and honest communication be allowed among team members? (5) Will each team member be respected and valued for his/her position on the team? (6) Are self-directed work teams effectively rewarded for accomplishments? (7) Have team members received adequate training to effectively complete their job tasks? Upon completion of the literature review and statistical data, and after analyzing the seven areas of team building techniques, it was determined three of the four teams were successful and effective. The only area of concern to the organization is that the participants felt they did not have true ownership of their teams; that is, team members were not given full empowerment. According to this study and the review of literature, full empowerment must be given to achieve successful and effective teams. If true empowerment is not given, the team will suffer in other areas of team building, and the organization will lose a valuable tool.

  16. Self-directed exploration provides a Ncs1-dependent learning bonus.

    PubMed

    Mun, Ho-Suk; Saab, Bechara J; Ng, Enoch; McGirr, Alexander; Lipina, Tatiana V; Gondo, Yoichi; Georgiou, John; Roder, John C

    2015-12-07

    Understanding the mechanisms of memory formation is fundamental to establishing optimal educational practices and restoring cognitive function in brain disease. Here, we show for the first time in a non-primate species, that spatial learning receives a special bonus from self-directed exploration. In contrast, when exploration is escape-oriented, or when the full repertoire of exploratory behaviors is reduced, no learning bonus occurs. These findings permitted the first molecular and cellular examinations into the coupling of exploration to learning. We found elevated expression of neuronal calcium sensor 1 (Ncs1) and dopamine type-2 receptors upon self-directed exploration, in concert with increased neuronal activity in the hippocampal dentate gyrus and area CA3, as well as the nucleus accumbens. We probed further into the learning bonus by developing a point mutant mouse (Ncs1(P144S/P144S)) harboring a destabilized NCS-1 protein, and found this line lacked the equivalent self-directed exploration learning bonus. Acute knock-down of Ncs1 in the hippocampus also decoupled exploration from efficient learning. These results are potentially relevant for augmenting learning and memory in health and disease, and provide the basis for further molecular and circuit analyses in this direction.

  17. Self-directed exploration provides a Ncs1-dependent learning bonus

    PubMed Central

    Mun, Ho-Suk; Saab, Bechara J.; Ng, Enoch; McGirr, Alexander; Lipina, Tatiana V.; Gondo, Yoichi; Georgiou, John; Roder, John C.

    2015-01-01

    Understanding the mechanisms of memory formation is fundamental to establishing optimal educational practices and restoring cognitive function in brain disease. Here, we show for the first time in a non-primate species, that spatial learning receives a special bonus from self-directed exploration. In contrast, when exploration is escape-oriented, or when the full repertoire of exploratory behaviors is reduced, no learning bonus occurs. These findings permitted the first molecular and cellular examinations into the coupling of exploration to learning. We found elevated expression of neuronal calcium sensor 1 (Ncs1) and dopamine type-2 receptors upon self-directed exploration, in concert with increased neuronal activity in the hippocampal dentate gyrus and area CA3, as well as the nucleus accumbens. We probed further into the learning bonus by developing a point mutant mouse (Ncs1P144S/P144S) harboring a destabilized NCS-1 protein, and found this line lacked the equivalent self-directed exploration learning bonus. Acute knock-down of Ncs1 in the hippocampus also decoupled exploration from efficient learning. These results are potentially relevant for augmenting learning and memory in health and disease, and provide the basis for further molecular and circuit analyses in this direction. PMID:26639399

  18. Inspiring Climate Education Excellence (ICEE): Developing self-directed professional development modules for secondary science teachers

    NASA Astrophysics Data System (ADS)

    Buhr, S. M.; Lynds, S. E.; McCaffrey, M. S.; Morton, E.

    2010-12-01

    Inspiring Climate Education Excellence (ICEE) is a NASA-funded project to develop online course modules and self-directed learning resources aligned with the Essential Principles of Climate Science. Following a national needs assessment survey and a face to face workshop to pilot test topics, a suite of online modules is being developed suitable for self-directed learning by secondary science teachers. Modules are designed around concepts and topics in which teachers express the most interest and need for instruction. Module design also includes attention to effective teaching strategies, such as awareness of student misconceptions, strategies for forestalling controversy and advice from master teachers on implementation and curriculum development. The resources are being developed in partnership with GLOBE, and the National Science Digital Library (NSDL) and is informed by the work of the Climate Literacy and Energy Awareness Network (CLEAN) project. ICEE will help to meet the professional development needs of teachers, including those participating in the GLOBE Student Climate Research Campaign. Modules and self-directed learning resources will be developed and disseminated in partnership with the National Science Digital Library (NSDL). This presentation introduces the needs assessment and pilot workshop data upon which the modules are based, and describes the modules that are available and in development.

  19. An Integrated In Vitro Imaging Platform for Characterizing Filarial Parasite Behavior within a Multicellular Microenvironment

    PubMed Central

    Kassis, Timothy; Skelton, Henry M.; Lu, Iris M.; Moorhead, Andrew R.; Dixon, J. Brandon

    2014-01-01

    Lymphatic Filariasis, a Neglected Tropical Disease, is caused by thread-like parasitic worms, including B. malayi, which migrate to the human lymphatic system following transmission. The parasites reside in collecting lymphatic vessels and lymph nodes for years, often resulting in lymphedema, elephantiasis or hydrocele. The mechanisms driving worm migration and retention within the lymphatics are currently unknown. We have developed an integrated in vitro imaging platform capable of quantifying B. malayi migration and behavior in a multicellular microenvironment relevant to the initial site of worm injection by incorporating the worm in a Polydimethylsiloxane (PDMS) microchannel in the presence of human dermal lymphatic endothelial cells (LECs) and human dermal fibroblasts (HDFs). The platform utilizes a motorized controllable microscope with CO2 and temperature regulation to allow for worm tracking experiments with high resolution over large length and time scales. Using post-acquisition algorithms, we quantified four parameters: 1) speed, 2) thrashing intensity, 3) percentage of time spent in a given cell region and 4) persistence ratio. We demonstrated the utility of our system by quantifying these parameters for L3 B. malayi in the presence of LECs and HDFs. Speed and thrashing increased in the presence of both cell types and were altered within minutes upon exposure to the anthelmintic drug, tetramisole. The worms displayed no targeted migration towards either cell type for the time course of this study (3 hours). When cells were not present in the chamber, worm thrashing correlated directly with worm speed. However, this correlation was lost in the presence of cells. The described platform provides the ability to further study B. malayi migration and behavior. PMID:25412444

  20. A Novel Cell Traction Force Microscopy to Study Multi-Cellular System

    PubMed Central

    Anand, Sandeep V.; Saif, Taher A.

    2014-01-01

    Traction forces exerted by adherent cells on their microenvironment can mediate many critical cellular functions. Accurate quantification of these forces is essential for mechanistic understanding of mechanotransduction. However, most existing methods of quantifying cellular forces are limited to single cells in isolation, whereas most physiological processes are inherently multi-cellular in nature where cell-cell and cell-microenvironment interactions determine the emergent properties of cell clusters. In the present study, a robust finite-element-method-based cell traction force microscopy technique is developed to estimate the traction forces produced by multiple isolated cells as well as cell clusters on soft substrates. The method accounts for the finite thickness of the substrate. Hence, cell cluster size can be larger than substrate thickness. The method allows computing the traction field from the substrate displacements within the cells' and clusters' boundaries. The displacement data outside these boundaries are not necessary. The utility of the method is demonstrated by computing the traction generated by multiple monkey kidney fibroblasts (MKF) and human colon cancerous (HCT-8) cells in close proximity, as well as by large clusters. It is found that cells act as individual contractile groups within clusters for generating traction. There may be multiple of such groups in the cluster, or the entire cluster may behave a single group. Individual cells do not form dipoles, but serve as a conduit of force (transmission lines) over long distances in the cluster. The cell-cell force can be either tensile or compressive depending on the cell-microenvironment interactions. PMID:24901766

  1. A novel cell traction force microscopy to study multi-cellular system.

    PubMed

    Tang, Xin; Tofangchi, Alireza; Anand, Sandeep V; Saif, Taher A

    2014-06-01

    Traction forces exerted by adherent cells on their microenvironment can mediate many critical cellular functions. Accurate quantification of these forces is essential for mechanistic understanding of mechanotransduction. However, most existing methods of quantifying cellular forces are limited to single cells in isolation, whereas most physiological processes are inherently multi-cellular in nature where cell-cell and cell-microenvironment interactions determine the emergent properties of cell clusters. In the present study, a robust finite-element-method-based cell traction force microscopy technique is developed to estimate the traction forces produced by multiple isolated cells as well as cell clusters on soft substrates. The method accounts for the finite thickness of the substrate. Hence, cell cluster size can be larger than substrate thickness. The method allows computing the traction field from the substrate displacements within the cells' and clusters' boundaries. The displacement data outside these boundaries are not necessary. The utility of the method is demonstrated by computing the traction generated by multiple monkey kidney fibroblasts (MKF) and human colon cancerous (HCT-8) cells in close proximity, as well as by large clusters. It is found that cells act as individual contractile groups within clusters for generating traction. There may be multiple of such groups in the cluster, or the entire cluster may behave a single group. Individual cells do not form dipoles, but serve as a conduit of force (transmission lines) over long distances in the cluster. The cell-cell force can be either tensile or compressive depending on the cell-microenvironment interactions.

  2. Modeling a synthetic multicellular clock: Repressilators coupled by quorum sensing

    PubMed Central

    Garcia-Ojalvo, Jordi; Elowitz, Michael B.; Strogatz, Steven H.

    2004-01-01

    Diverse biochemical rhythms are generated by thousands of cellular oscillators that somehow manage to operate synchronously. In fields ranging from circadian biology to endocrinology, it remains an exciting challenge to understand how collective rhythms emerge in multicellular structures. Using mathematical and computational modeling, we study the effect of coupling through intercell signaling in a population of Escherichia coli cells expressing a synthetic biological clock. Our results predict that a diverse and noisy community of such genetic oscillators interacting through a quorum-sensing mechanism should self-synchronize in a robust way, leading to a substantially improved global rhythmicity in the system. As such, the particular system of coupled genetic oscillators considered here might be a good candidate to provide the first quantitative example of a synchronization transition in a population of biological oscillators. PMID:15256602

  3. Sorodiplophrys stercorea: Another Novel Lineage of Sorocarpic Multicellularity.

    PubMed

    Tice, Alexander K; Silberman, Jeffrey D; Walthall, Austin C; Le, Khoa N D; Spiegel, Frederick W; Brown, Matthew W

    2016-09-01

    Sorodiplophrys stercorea is a sorocarpic organism that utilizes filose pseudopodia for locomotion and absorptive nutrition. It has traditionally been considered to be a member of the Labyrinthulae based on its morphology. Its closest relatives were thought to be species in the taxon Diplophrys. Since the genus Diplophrys has been shown to be paraphyletic and S. stercorea has pseudopodia similar to some members of Rhizaria, we examined its relationship with other eukaryotes. We obtained four isolates from the dung of cow and horse, brought each into monoeukaryotic culture, and sequenced their SSU rRNA gene for phylogenetic analysis. All our isolates were shown to form a monophyletic group in the Labyrinthulae, nested in the Amphifiloidea clade. Our results demonstrate that Sorodiplophrys is more closely related to species of the genus Amphifila than to Diplophrys and represents an additional independent origin of sorocarpic multicellularity among eukaryotes. This study represents the first confirmed sorocarpic lifestyle in the Stramenopiles.

  4. Validation of Immune Cell Modules in Multicellular Transcriptomic Data

    PubMed Central

    Heather, James M.; Byng-Maddick, Rachel; Guppy, Naomi; Ellis, Matthew; Turner, Carolin T.; Chain, Benjamin M.; Noursadeghi, Mahdad

    2017-01-01

    Numerous gene signatures, or modules have been described to evaluate the immune cell composition in transcriptomes of multicellular tissue samples. However, significant diversity in module gene content for specific cell types is associated with heterogeneity in their performance. In order to rank modules that best reflect their purported association, we have generated the modular discrimination index (MDI) score that assesses expression of each module in the target cell type relative to other cells. We demonstrate that MDI scores predict modules that best reflect independently validated differences in cellular composition, and correlate with the covariance between cell numbers and module expression in human blood and tissue samples. Our analyses demonstrate that MDI scores provide an ordinal summary statistic that reliably ranks the accuracy of gene expression modules for deconvolution of cell type abundance in transcriptional data. PMID:28045996

  5. Engineering multicellular logic in bacteria with metabolic wires.

    PubMed

    Silva-Rocha, Rafael; de Lorenzo, Victor

    2014-04-18

    Aromatic biodegradation pathways of environmental bacteria are vast sources of matching trios of enzymes, substrates and regulators that can be refactored to run logic operations through cell-to-cell communication. As a proof of concept, the connection between two Pseudomonas putida strains using benzoic acid as the wiring molecule is presented. In this system, a sender strain harboring the TOL pathway for biodegradation of aromatics processed toluene as input and generated benzoate as the output signal. Diffusion of such metabolic intermediate to the medium was then sensed by a second strain (the receiver) that used benzoate as input for a new logic gate producing a visual output (i.e., light emission). The setup was functional irrespective of whether sender and receiver cells were in direct contact or in liquid culture. These results highlight the potential of environmental metabolic pathways as sources of building blocks for the engineering of multicellular logic in prokaryotic systems.

  6. Multicellular tumor spheroid interactions with bone cells and bone

    SciTech Connect

    Wezeman, F.H.; Guzzino, K.M.; Waxler, B.

    1985-10-01

    In vitro coculture techniques were used to study HSDM1C1 murine fibrosarcoma multicellular tumor spheroid (HSDM1C1-MTS) interactions with mouse calvarial bone cells having osteoblastic characteristics and mouse bone explants. HSDM1C1-MTS attached to confluent bone cell monolayers and their attachment rate was quantified. HSDM1C1-MTS interaction with bone cells was further demonstrated by the release of /sup 3/H-deoxyuridine from prelabeled bone cells during coculture with multicellular tumor spheroids. HSDM1C1-MTS-induced cytotoxicity was mimicked by the addition of 10(-5) M prostaglandin E2 (PGE2) to /sup 3/H-deoxyuridine-labeled bone cells. The effects of low (10(-9) M) and high (10(-5) M) concentrations of PGE2 on bone cell proliferation were also studied. Higher concentrations of PGE2 inhibited bone cell proliferation. HSDM1C1-MTS resorbed living explants in the presence of indomethacin, suggesting that other tumor cell products may also participate in bone resorption. HSDM1C1-MTS caused direct bone resorption as measured by the significantly elevated release of /sup 45/Ca from prelabeled, devitalized calvaria. However, the growth of a confluent bone cell layer on devitalized, /sup 45/Ca-prelabeled calvaria resulted in a significant reduction in the amount of /sup 45/Ca released subsequent to the seeding of HSDM1C1-MTS onto the explants. Bone cells at the bone surface may act as a barrier against invasion and tumor cell-mediated bone resorption. Violation of this cellular barrier is achieved, in part, by tumor cell products.

  7. Green Algae and the Origins of Multicellularity in the Plant Kingdom

    PubMed Central

    Umen, James G.

    2014-01-01

    The green lineage of chlorophyte algae and streptophytes form a large and diverse clade with multiple independent transitions to produce multicellular and/or macroscopically complex organization. In this review, I focus on two of the best-studied multicellular groups of green algae: charophytes and volvocines. Charophyte algae are the closest relatives of land plants and encompass the transition from unicellularity to simple multicellularity. Many of the innovations present in land plants have their roots in the cell and developmental biology of charophyte algae. Volvocine algae evolved an independent route to multicellularity that is captured by a graded series of increasing cell-type specialization and developmental complexity. The study of volvocine algae has provided unprecedented insights into the innovations required to achieve multicellularity. PMID:25324214

  8. Green algae and the origins of multicellularity in the plant kingdom.

    PubMed

    Umen, James G

    2014-10-16

    The green lineage of chlorophyte algae and streptophytes form a large and diverse clade with multiple independent transitions to produce multicellular and/or macroscopically complex organization. In this review, I focus on two of the best-studied multicellular groups of green algae: charophytes and volvocines. Charophyte algae are the closest relatives of land plants and encompass the transition from unicellularity to simple multicellularity. Many of the innovations present in land plants have their roots in the cell and developmental biology of charophyte algae. Volvocine algae evolved an independent route to multicellularity that is captured by a graded series of increasing cell-type specialization and developmental complexity. The study of volvocine algae has provided unprecedented insights into the innovations required to achieve multicellularity. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

  9. Intramyocardial Fibroblast - Myocyte Communication

    PubMed Central

    Kakkar, Rahul; Lee, Richard T.

    2009-01-01

    Cardiac fibroblasts are emerging as key components of normal cardiac function as well as the response to stressors and injury. These most numerous cells of the heart interact with myocytes via paracrine mechanisms, alterations in extracellular matrix homeostasis, and direct cell-cell interactions. It is possible that they are a contributor to the inability of adult myocytes to proliferate, and may influence cardiac progenitor biology. Furthering our understanding of how cardiac fibroblast and myocytes interact may provide an avenue to novel treatments for heart failure prevention. This review discusses the most recent concepts in cardiac fibroblast-myocyte communication and areas of potential future research. PMID:20056945

  10. Mirror-induced self-directed behaviors in rhesus monkeys after visual-somatosensory training.

    PubMed

    Chang, Liangtang; Fang, Qin; Zhang, Shikun; Poo, Mu-ming; Gong, Neng

    2015-01-19

    Mirror self-recognition is a hallmark of higher intelligence in humans. Most children recognize themselves in the mirror by 2 years of age. In contrast to human and some great apes, monkeys have consistently failed the standard mark test for mirror self-recognition in all previous studies. Here, we show that rhesus monkeys could acquire mirror-induced self-directed behaviors resembling mirror self-recognition following training with visual-somatosensory association. Monkeys were trained on a monkey chair in front of a mirror to touch a light spot on their faces produced by a laser light that elicited an irritant sensation. After 2-5 weeks of training, monkeys had learned to touch a face area marked by a non-irritant light spot or odorless dye in front of a mirror and by a virtual face mark on the mirroring video image on a video screen. Furthermore, in the home cage, five out of seven trained monkeys showed typical mirror-induced self-directed behaviors, such as touching the mark on the face or ear and then looking at and/or smelling their fingers, as well as spontaneously using the mirror to explore normally unseen body parts. Four control monkeys of a similar age that went through mirror habituation but had no training of visual-somatosensory association did not pass any mark tests and did not exhibit mirror-induced self-directed behaviors. These results shed light on the origin of mirror self-recognition and suggest a new approach to studying its neural mechanism.

  11. Movement-Related Theta Rhythm in Humans: Coordinating Self-Directed Hippocampal Learning

    PubMed Central

    Kaplan, Raphael; Doeller, Christian F.; Barnes, Gareth R.; Litvak, Vladimir; Düzel, Emrah; Bandettini, Peter A.; Burgess, Neil

    2012-01-01

    The hippocampus is crucial for episodic or declarative memory and the theta rhythm has been implicated in mnemonic processing, but the functional contribution of theta to memory remains the subject of intense speculation. Recent evidence suggests that the hippocampus might function as a network hub for volitional learning. In contrast to human experiments, electrophysiological recordings in the hippocampus of behaving rodents are dominated by theta oscillations reflecting volitional movement, which has been linked to spatial exploration and encoding. This literature makes the surprising cross-species prediction that the human hippocampal theta rhythm supports memory by coordinating exploratory movements in the service of self-directed learning. We examined the links between theta, spatial exploration, and memory encoding by designing an interactive human spatial navigation paradigm combined with multimodal neuroimaging. We used both non-invasive whole-head Magnetoencephalography (MEG) to look at theta oscillations and Functional Magnetic Resonance Imaging (fMRI) to look at brain regions associated with volitional movement and learning. We found that theta power increases during the self-initiation of virtual movement, additionally correlating with subsequent memory performance and environmental familiarity. Performance-related hippocampal theta increases were observed during a static pre-navigation retrieval phase, where planning for subsequent navigation occurred. Furthermore, periods of the task showing movement-related theta increases showed decreased fMRI activity in the parahippocampus and increased activity in the hippocampus and other brain regions that strikingly overlap with the previously observed volitional learning network (the reverse pattern was seen for stationary periods). These fMRI changes also correlated with participant's performance. Our findings suggest that the human hippocampal theta rhythm supports memory by coordinating exploratory

  12. Self-directed learning readiness and learning styles among Saudi undergraduate nursing students.

    PubMed

    El-Gilany, Abdel-Hady; Abusaad, Fawzia El Sayed

    2013-09-01

    Self-directed learning has become a focus for nursing education in the past few decades due to the complexity and changes in nursing profession development. On the other hand, the Kolb's learning style could identify student's preference for perceiving and processing information. This study was performed to determine Saudi nursing students' readiness for self-directed learning; to identify their learning styles and to find out the relation between these two concepts. Cross-sectional descriptive study. Nursing department of faculty of Applied Medical Sciences, Al-Jouf University, Saudi Arabia. Two hundred and seventy-five undergraduate Saudi nursing students. Data was collected using self-administered questionnaires covering the demographic features of students, Fisher's self-directed learning readiness (SDLR) scale, and the Kolb's learning styles inventory. The mean scores of self-management, desire for learning, self-control and the overall SDLR were 51.3 ± 5.9, 48.4 ± 5.5, 59.9 ± 6.7, and 159.6 ± 13.8; respectively. About 77% (211) of students have high level of SDLR. The percentages of converger, diverger, assimilator and accommodator learning styles are 35.6%, 25.8%, 25.55% and 13.1%; respectively. The mean score of self-management, desire for learning, self-control and overall SDLR scale did not vary with any of the studied variables. There is no association between the level of SDLR and the learning styles. The high level of SDLR and the dominant converger learning style among undergraduate nursing students will have a positive implication for their education and post-employment continuing nursing education. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Movement-related theta rhythm in humans: coordinating self-directed hippocampal learning.

    PubMed

    Kaplan, Raphael; Doeller, Christian F; Barnes, Gareth R; Litvak, Vladimir; Düzel, Emrah; Bandettini, Peter A; Burgess, Neil

    2012-01-01

    The hippocampus is crucial for episodic or declarative memory and the theta rhythm has been implicated in mnemonic processing, but the functional contribution of theta to memory remains the subject of intense speculation. Recent evidence suggests that the hippocampus might function as a network hub for volitional learning. In contrast to human experiments, electrophysiological recordings in the hippocampus of behaving rodents are dominated by theta oscillations reflecting volitional movement, which has been linked to spatial exploration and encoding. This literature makes the surprising cross-species prediction that the human hippocampal theta rhythm supports memory by coordinating exploratory movements in the service of self-directed learning. We examined the links between theta, spatial exploration, and memory encoding by designing an interactive human spatial navigation paradigm combined with multimodal neuroimaging. We used both non-invasive whole-head Magnetoencephalography (MEG) to look at theta oscillations and Functional Magnetic Resonance Imaging (fMRI) to look at brain regions associated with volitional movement and learning. We found that theta power increases during the self-initiation of virtual movement, additionally correlating with subsequent memory performance and environmental familiarity. Performance-related hippocampal theta increases were observed during a static pre-navigation retrieval phase, where planning for subsequent navigation occurred. Furthermore, periods of the task showing movement-related theta increases showed decreased fMRI activity in the parahippocampus and increased activity in the hippocampus and other brain regions that strikingly overlap with the previously observed volitional learning network (the reverse pattern was seen for stationary periods). These fMRI changes also correlated with participant's performance. Our findings suggest that the human hippocampal theta rhythm supports memory by coordinating exploratory

  14. Clinically meaningful changes in functional performance resulting from self-directed interventions in individuals with arthritis.

    PubMed

    Baruth, M; Wilcox, S; McClenaghan, B; Becofsky, K; Schoffman, D E

    2016-04-01

    To examine the clinical meaningfulness of changes observed in functional performance from two self-directed interventions targeting adults with arthritis. Randomized controlled trial. Participants (n = 312) were randomized to a 12-week self-directed exercise or nutrition intervention. Objective measures of functional performance (6-minute walk, seated reach, grip strength, 30-second chair stand, gait speed, balance) were obtained at baseline, 12 weeks, and nine months. Minimally (≥0.20 standard deviation) and substantially (≥0.50) meaningful changes in functional performance were examined. Changes in the percent 'impaired' and at risk for losing independence using established standards, and associations between physical activity and impairment/risk status were also examined. Group × Time interactions were not significant; therefore groups were combined in all analyses. Minimally (31-71%) and substantially (13-54%) meaningful changes in function were shown. There was a significant decrease in the percentage of participants 'impaired' on the 30-second chair stand (both time points) and gait speed (nine months). The percentage of participants at risk for losing independence significantly decreased for the 30-second chair stand (both time points) and the 6-minute walk (nine months). Those engaging in ≥2 h of leisure-time physical activity were significantly less likely to be impaired on the 6-minute walk, 30-second chair stand, and gait speed at 12 weeks, and the 6-minute walk at nine months. Interventions that can slow functional declines, and ideally result in clinically meaningful improvements in functional performance among adults with arthritis are needed. Meaningful improvements in various indicators of functional performance can result from self-directed exercise and nutrition programs. These types of programs have the potential for wide-spread dissemination, and thus broad reach. Copyright © 2016 The Royal Society for Public Health. Published by

  15. "Walk with me…" : A journey of self-directed holistic cancer education by medical students.

    PubMed

    Lakhtakia, Ritu; Al Badi, Majid; Al Obaidani, Athari; Al Jarrah, Adil

    2014-03-01

    Cancer education offers an ideal opportunity to inspire and initiate medical students in life-long, self-directed learning. Early and innovative out-of-the-box learning experiences, tailored to appeal to a multi-media savvy generation of medical students, form the theme of these reflections. Students never fail to surprise teachers when the seed of an idea appeals and motivates their minds. 'Walk with me…' is the story of a journey together of students, mentors, patients, and the manifold professionals who manage breast cancer.

  16. Self-directed learning in the context of a nursing curriculum: development of a learning plan.

    PubMed

    Majumdar, B

    1996-06-01

    The rapid pace at which biological health breakthroughs and advancements in technology occur is creating unique challenges to health care programmes. The curricula of all health care programmes will need to be set in learning environments where students will be able to develop learning skills that are transportable across situations, over a whole lifetime. This article attempts to focus on self-directed learning (SDL) concepts and the development of a learning contract/plan, including the roles of both the student and faculty in self-learning approaches and contractual development.

  17. Synergistic cooperation promotes multicellular performance and unicellular free-rider persistence

    PubMed Central

    Driscoll, William W; Travisano, Michael

    2017-01-01

    The evolution of multicellular life requires cooperation among cells, which can be undermined by intra-group selection for selfishness. Theory predicts that selection to avoid non-cooperators limits social interactions among non-relatives, yet previous evolution experiments suggest that intra-group conflict is an outcome, rather than a driver, of incipient multicellular life cycles. Here we report the evolution of multicellularity via two distinct mechanisms of group formation in the unicellular budding yeast Kluyveromyces lactis. Cells remain permanently attached following mitosis, giving rise to clonal clusters (staying together); clusters then reversibly assemble into social groups (coming together). Coming together amplifies the benefits of multicellularity and allows social clusters to collectively outperform solitary clusters. However, cooperation among non-relatives also permits fast-growing unicellular lineages to ‘free-ride' during selection for increased size. Cooperation and competition for the benefits of multicellularity promote the stable coexistence of unicellular and multicellular genotypes, underscoring the importance of social and ecological context during the transition to multicellularity. PMID:28580966

  18. Synergistic cooperation promotes multicellular performance and unicellular free-rider persistence.

    PubMed

    Driscoll, William W; Travisano, Michael

    2017-06-05

    The evolution of multicellular life requires cooperation among cells, which can be undermined by intra-group selection for selfishness. Theory predicts that selection to avoid non-cooperators limits social interactions among non-relatives, yet previous evolution experiments suggest that intra-group conflict is an outcome, rather than a driver, of incipient multicellular life cycles. Here we report the evolution of multicellularity via two distinct mechanisms of group formation in the unicellular budding yeast Kluyveromyces lactis. Cells remain permanently attached following mitosis, giving rise to clonal clusters (staying together); clusters then reversibly assemble into social groups (coming together). Coming together amplifies the benefits of multicellularity and allows social clusters to collectively outperform solitary clusters. However, cooperation among non-relatives also permits fast-growing unicellular lineages to 'free-ride' during selection for increased size. Cooperation and competition for the benefits of multicellularity promote the stable coexistence of unicellular and multicellular genotypes, underscoring the importance of social and ecological context during the transition to multicellularity.

  19. Synchronization of Eukaryotic Flagella and the Evolution of Multicellularity

    NASA Astrophysics Data System (ADS)

    Goldstein, Raymond

    2009-03-01

    Flagella, among the most highly conserved structures in eukaryotes, are responsible for such tasks as fluid transport, motility and phototaxis, establishment of embryonic left-right asymmetry, and intercellular communication, and are thought to have played a key role in the development of multicellularity. These tasks are usually performed by the coordinated action of groups of flagella (from pairs to thousands), which display various types of spatio-temporal organization. The origin and quantitative characterization of flagellar synchronization has remained an important open problem, involving interplay between intracellular biochemistry and interflagellar mechanical/hydrodynamic coupling. The Volvocine green algae serve as useful model organisms for the study of these phenomena, as they form a lineage spanning from unicellular Chlamydomonas to germ-soma differentiated Volvox, having as many as 50,000 biflagellated surface somatic cells. In this talk I will describe extensive studies [1], using micromanipulation and high-speed imaging, of the flagellar synchronization of two key species - Chlamydomonas reinhardtii and Volvox carteri - over tens of thousands of cycles. With Chlamydomonas we find that the flagellar dynamics moves back and forth between a stochastic synchronized state consistent with a simple model of hydrodynamically coupled noisy oscillators, and a deterministic one driven by a large interflagellar frequency difference. These results reconcile previously contradictory studies, based on short observations, showing only one or the other of these two states, and, more importantly, show that the flagellar beat frequencies themselves are regulated by the cell. Moreover, high-resolution three-dimensional tracking of swimming cells provides strong evidence that these dynamical states are related to reorientation events in the trajectories, yielding a eukaryotic equivalent of the ``run and tumble'' motion of peritrichously flagellated bacteria. The degree

  20. Computational modeling of multicellular constructs with the material point method.

    PubMed

    Guilkey, James E; Hoying, James B; Weiss, Jeffrey A

    2006-01-01

    Computational modeling of the mechanics of cells and multicellular constructs with standard numerical discretization techniques such as the finite element (FE) method is complicated by the complex geometry, material properties and boundary conditions that are associated with such systems. The objectives of this research were to apply the material point method (MPM), a meshless method, to the modeling of vascularized constructs by adapting the algorithm to accurately handle quasi-static, large deformation mechanics, and to apply the modified MPM algorithm to large-scale simulations using a discretization that was obtained directly from volumetric confocal image data. The standard implicit time integration algorithm for MPM was modified to allow the background computational grid to remain fixed with respect to the spatial distribution of material points during the analysis. This algorithm was used to simulate the 3D mechanics of a vascularized scaffold under tension, consisting of growing microvascular fragments embedded in a collagen gel, by discretizing the construct with over 13.6 million material points. Baseline 3D simulations demonstrated that the modified MPM algorithm was both more accurate and more robust than the standard MPM algorithm. Scaling studies demonstrated the ability of the parallel code to scale to 200 processors. Optimal discretization was established for the simulations of the mechanics of vascularized scaffolds by examining stress distributions and reaction forces. Sensitivity studies demonstrated that the reaction force during simulated extension was highly sensitive to the modulus of the microvessels, despite the fact that they comprised only 10.4% of the volume of the total sample. In contrast, the reaction force was relatively insensitive to the effective Poisson's ratio of the entire sample. These results suggest that the MPM simulations could form the basis for estimating the modulus of the embedded microvessels through a parameter

  1. Development of cell differentiation in the transition to multicellularity: a dynamical modeling approach.

    PubMed

    Mora Van Cauwelaert, Emilio; Arias Del Angel, Juan A; Benítez, Mariana; Azpeitia, Eugenio M

    2015-01-01

    Multicellularity has emerged and continues to emerge in a variety of lineages and under diverse environmental conditions. In order to attain individuality and integration, multicellular organisms must exhibit spatial cell differentiation, which in turn allows cell aggregates to robustly generate traits and behaviors at the multicellular level. Nevertheless, the mechanisms that may lead to the development of cellular differentiation and patterning in emerging multicellular organisms remain unclear. We briefly review two conceptual frameworks that have addressed this issue: the cooperation-defection framework and the dynamical patterning modules (DPMs) framework. Then, situating ourselves in the DPM formalism first put forward by S. A. Newman and collaborators, we state a hypothesis for cell differentiation and arrangement in cellular masses of emerging multicellular organisms. Our hypothesis is based on the role of the generic cell-to-cell communication and adhesion patterning mechanisms, which are two fundamental mechanisms for the evolution of multicellularity, and whose molecules seem to be well-conserved in extant multicellular organisms and their unicellular relatives. We review some fundamental ideas underlying this hypothesis and contrast them with empirical and theoretical evidence currently available. Next, we use a mathematical model to illustrate how the mechanisms and assumptions considered in the hypothesis we postulate may render stereotypical arrangements of differentiated cells in an emerging cellular aggregate and may contribute to the variation and recreation of multicellular phenotypes. Finally, we discuss the potential implications of our approach and compare them to those entailed by the cooperation-defection framework in the study of cell differentiation in the transition to multicellularity.

  2. Development of cell differentiation in the transition to multicellularity: a dynamical modeling approach

    PubMed Central

    Mora Van Cauwelaert, Emilio; Arias Del Angel, Juan A.; Benítez, Mariana; Azpeitia, Eugenio M.

    2015-01-01

    Multicellularity has emerged and continues to emerge in a variety of lineages and under diverse environmental conditions. In order to attain individuality and integration, multicellular organisms must exhibit spatial cell differentiation, which in turn allows cell aggregates to robustly generate traits and behaviors at the multicellular level. Nevertheless, the mechanisms that may lead to the development of cellular differentiation and patterning in emerging multicellular organisms remain unclear. We briefly review two conceptual frameworks that have addressed this issue: the cooperation-defection framework and the dynamical patterning modules (DPMs) framework. Then, situating ourselves in the DPM formalism first put forward by S. A. Newman and collaborators, we state a hypothesis for cell differentiation and arrangement in cellular masses of emerging multicellular organisms. Our hypothesis is based on the role of the generic cell-to-cell communication and adhesion patterning mechanisms, which are two fundamental mechanisms for the evolution of multicellularity, and whose molecules seem to be well-conserved in extant multicellular organisms and their unicellular relatives. We review some fundamental ideas underlying this hypothesis and contrast them with empirical and theoretical evidence currently available. Next, we use a mathematical model to illustrate how the mechanisms and assumptions considered in the hypothesis we postulate may render stereotypical arrangements of differentiated cells in an emerging cellular aggregate and may contribute to the variation and recreation of multicellular phenotypes. Finally, we discuss the potential implications of our approach and compare them to those entailed by the cooperation-defection framework in the study of cell differentiation in the transition to multicellularity. PMID:26157427

  3. 'It's your problem, not mine': does competence have anything to do with desire and aspiration to self-direct?

    PubMed

    Crozier, Michelle; Muenchberger, Heidi

    2013-11-01

    The current disability policy paradigm operating across all states in Australia is self-direction. This central movement is closely linked to preparations for a National Disability Insurance Scheme called DisabilityCare. We provide one perspective in relation to self-direction in Australia including assumptions about aspirations to self-direct and the limited research evidence base that is available even though anecdotally self-direction practices have been occurring for many years. We conclude that by developing a funding platform, such as DisabilityCare, that empowers people with a disability to make decisions about their own fundamental needs and the fulfilment of them, it will lead to a society that supports people to access and achieve a 'typical' and desired life.

  4. Cooperatively Generated Stresslet Flows Supply Fresh Fluid to Multicellular Choanoflagellate Colonies

    NASA Astrophysics Data System (ADS)

    Roper, Marcus; Dayel, Mark J.; Pepper, Rachel E.; Koehl, M. A. R.

    2013-05-01

    The flagellated protozoan Salpingoeca rosetta is one of the closest relatives of multicellular animals. Unicellular S. rosetta can be induced to form multicellular colonies, but colonies swim more slowly than individual cells so the advantages conferred by colony formation are uncertain. Here we use theoretical models to show that hydrodynamic cooperation between cells can increase the fluid supply to the colony, an important predictor of feeding rate. Our results suggest that hydrodynamic benefits may have been an important selective factor in the evolution of early multicellular animals.

  5. Sliding mode control for a three phase multicellular inverter dedicated to renewable energy systems

    NASA Astrophysics Data System (ADS)

    Hemici, K.; Zegaoui, A.; Djahbar, A.; Bokhtache, A. Aissa; Kessaissia, F. Z.; Allouache, H.; Mahmoudi, M. O.; Aillerie, M.

    2017-02-01

    In this paper, Sliding Mode controller has been sized to control multi-cell converters configured as a three-phase multicellular inverter. Unlike traditional inverters, multicellular inverters have the following advantages: lower switching frequency, high number of output levels, and less voltage constraints on the power switch. Significant performances are provided with this structure, which is constituted with flying capacitors. The main purpose of this paper is to present the model and generate commutation sliding-surfaces based on a Lyapunov function. The performed simulations point the efficiency of the proposed strategy with a three-phase multicellular inverters and allow to assess the performances and the robustness of the synthesized controller.

  6. Crowding increases salivary cortisol but not self-directed behavior in captive baboons.

    PubMed

    Pearson, Brandon L; Reeder, DeeAnn M; Judge, Peter G

    2015-04-01

    Reduced space can lead to crowding in social animals. Crowding increases the risk of agonistic interactions that, in turn, may require additional physiological defensive coping mechanisms affecting health. To determine the stress induced from increased social density in a group of nineteen baboons living in an indoor/outdoor enclosure, saliva cortisol levels and rates of anxiety-related behavior were analyzed across two unique crowding episodes. Initially, mean salivary cortisol levels when animals were restricted to their indoor quarters were compared to those when they also had access to their larger outdoor enclosure. Then, mean cortisol levels were compared before, during, and after two distinct crowding periods of long and short duration. Crowding resulted in significantly elevated cortisol during crowding periods compared to non-crowded periods. Cortisol levels returned to baseline following two crowding episodes contrasting in their length and ambient climate conditions. These cortisol elevations indicate greater metabolic costs of maintaining homeostasis under social stress resulting from reduced space. Self-directed behavior, conversely, was not reliably elevated during crowding. Results suggest that the potential for negative social interactions, and/or the uncertainty associated with social threat can cause physiological stress responses detected by salivary cortisol. Self-directed behavioral measures of stress may constitute inadequate indicators of social stress in colony-housed monkeys or represent subjective emotional arousal unrelated to hypothalamic-pituitary adrenal axis activation. © 2015 Wiley Periodicals, Inc.

  7. Self-Directed Affiliation and Autonomy Across Acute and Continuation Phase Cognitive Therapy for Recurrent Depression

    PubMed Central

    Clark, Lee Anna; Jarrett, Robin B.

    2005-01-01

    Using Benjamin’s (2000) Structural Analysis of Social Behavior, we evaluated change in "self-directed" affiliation and autonomy and prediction of treatment response and relapse/recurrence among adult outpatients with recurrent major depressive disorder consenting to acute phase cognitive therapy (A–CT; Beck, Rush, Shaw, & Emery, 1979; N = 156); A–CT responders randomized (N = 84) to 8 months of continuation phase cognitive therapy (C–CT; Jarrett, 1989; Jarrett et al., 1998; Jarrett & Kraft, 1997) or assessment-only control; and C–CT and control patients entering a 16-month, assessment-only follow-up (N = 74). Self-directed affiliation and autonomy increased after A–CT, and C–CT further increased affiliation and autonomy. Affiliation and autonomy did not predict A–CT response, but lower affiliation and higher autonomy pre-A–CT predicted relapse/recurrence post-A–CT. We discuss potential clinical implications of these results and present case examples to illustrate patterns of change. PMID:15548462

  8. Validating the Japanese Self-Directed Learning Readiness Scale for Nursing Education.

    PubMed

    Fujino-Oyama, Yumiko; Maeda, Rumi; Maru, Mitsue; Inoue, Tomoko

    2016-02-01

    The Self-Directed Learning Readiness Scale for Nursing Education (SDLRSNE) assesses the extent to which an individual has the characteristics, capabilities, and attitudes required for self-directed learning. This study aimed to validate the Japanese version of the SDLRSNE with graduate-level nursing students. Confirmatory factor analyses, using data from a cross-sectional online survey of 376 nursing students, were conducted to examine construct validity. Relationships with potential related factors were analyzed to evaluate construct validity. Reliability was evaluated with item analysis and Cronbach's alpha. Factor analyses revealed that three-factor and individual subscale models had a moderate-to-poor fit. No meaningful relationship with potential related factors was noted. Reliability measurements indicated a moderate fit to data. This study could not confirm that the Japanese version of the SDLRSNE had acceptable levels of reliability and validity when tested with graduate-level nursing students. Further research is needed to examine the psychometric properties of the Japanese version of the SDLRSNE with other adult nursing learners or with graduate-level nursing students in other countries. Copyright 2016, SLACK Incorporated.

  9. Self-directed work teams: application to a drug information center.

    PubMed

    Stachnik, J M; Nunn-Thompson, C L; Simon, P A; Seeger, J D; Markind, J E; Ross, J R; Clark, T

    1997-03-01

    To describe the transition of a drug information center from a traditionally managed center to a self-directed work team responsible for service, education, research, and drug use policy development. To adapt to economic, educational, and technologic changes, traditional management structures in healthcare organizations are being reassessed. In some instances, a team approach (using self-directed work teams [SDWTs]) is being implemented. SDWTs have the potential to provide a number of benefits to an organization, including reduced costs and greater employee motivation. The University of Illinois at Chicago Drug Information Center had functioned under a traditional management structure. For economic and professional reasons, the management structure of the center was changed to an SDWT, prompting a reevaluation of the mission and activities of the center. Although still in transition, the center's change to a team structure has proven to be positive. The nature of the SDWT requires greater involvement by team members in all aspects of the center's operation, adding to the experience of team members. The team structure also allows for greater freedom to pursue projects of personal interest to individual team members. A number of issues still need to be resolved, such as performance-based compensation and peer- and self-evaluations. SDWTs can provide many benefits. The successful implementation of an SDWT, however, has a number of requirements, the most important of which are a commitment from management and effective communication among team members and with management.

  10. Initial Validation of the Self-Directed Violence Picture System (SDVPS).

    PubMed

    Nazem, Sarra; Forster, Jeri E; Brenner, Lisa A

    2017-02-16

    A better understanding of factors that differentiate those who only experience suicidal ideation from those who engage in self-directed violence (SDV) is critical for suicide prevention efforts (Klonsky & May, 2014; May & Klonsky, 2016). To identify who is at greatest risk for death by suicide, it is imperative that new innovative assessment tools be created to facilitate behavioral measurement of key constructs associated with increased risk for SDV. The aim of the current study was to develop and validate a set of suicide-specific images, called the Self-Directed Violence Picture System (SDVPS), to help meet this need. A sample of 119 U.S. military veterans provided valence, arousal, and dominance ratings on the SDVPS. These ratings were compared to International Affective Picture System (IAPS) negative, neutral, and positive images. SDVPS images were rated with significantly greater negative valence and elicited decreased feelings of being in control than did IAPS positive (p < .001, p < .001), IAPS negative (p = .03, p = .001), and IAPS neutral (p < .001, p < .001) images. SDVPS images were also rated with significantly greater arousal than were IAPS neutral images (p < .001). Initial validation data support that the SDVPS images functioned as intended. Although continued validation of the SDVPS in other populations is necessary, the SDVPS may become a new tool by which researchers can begin to systematically and reliably examine reactions to suicide-related content using behavioral and/or experimental paradigms. (PsycINFO Database Record

  11. Self-directed learning readiness of Asian students: students perspective on a hybrid problem based learning curriculum

    PubMed Central

    Susilo, Astrid P.; van Berkel, Henk

    2016-01-01

    Objectives To identify the student’s readiness to perform self-directed learning and the underlying factors influencing it on the hybrid problem based learning curriculum. Methods A combination of quantitative and qualitative studies was conducted in five medical schools in Indonesia. In the quantitative study, the Self Directed Learning Readiness Scale was distributed to all students in all batches, who had experience with the hybrid problem based curriculum. They were categorized into low- and high -level based on the score of the questionnaire. Three focus group discussions (low-, high-, and mixed level) were conducted in the qualitative study with six to twelve students chosen randomly from each group to find the factors influencing their self-directed learning readiness. Two researchers analysed the qualitative data as a measure of triangulation. Results The quantitative study showed only half of the students had a high-level of self-directed learning readiness, and a similar trend also occurred in each batch. The proportion of students with a high level of self-directed learning readiness was lower in the senior students compared to more junior students. The qualitative study showed that problem based learning processes, assessments, learning environment, students’ life styles, students’ perceptions of the topics, and mood, were factors influencing their self-directed learning. Conclusion A hybrid problem based curriculum may not fully affect the students’ self-directed learning. The curriculum system, teacher’s experiences, student’s background and cultural factors might contribute to the difficulties for the student’s in conducting self-directed learning. PMID:27915308

  12. Medicaid program; self-directed personal assistance services program State Plan option (cash and counseling). Final rule.

    PubMed

    2008-10-03

    This final rule provides guidance to States that want to administer self-directed personal assistance services through their State Plans, as authorized by the Deficit Reduction Act of 2005. The State plan option allows beneficiaries, through an approved self-directed services plan and budget, to purchase personal assistance services. The rule also provides guidance to ensure beneficiary health and welfare and financial accountability of the State Plan option.

  13. Biocellion: accelerating computer simulation of multicellular biological system models

    PubMed Central

    Kang, Seunghwa; Kahan, Simon; McDermott, Jason; Flann, Nicholas; Shmulevich, Ilya

    2014-01-01

    Motivation: Biological system behaviors are often the outcome of complex interactions among a large number of cells and their biotic and abiotic environment. Computational biologists attempt to understand, predict and manipulate biological system behavior through mathematical modeling and computer simulation. Discrete agent-based modeling (in combination with high-resolution grids to model the extracellular environment) is a popular approach for building biological system models. However, the computational complexity of this approach forces computational biologists to resort to coarser resolution approaches to simulate large biological systems. High-performance parallel computers have the potential to address the computing challenge, but writing efficient software for parallel computers is difficult and time-consuming. Results: We have developed Biocellion, a high-performance software framework, to solve this computing challenge using parallel computers. To support a wide range of multicellular biological system models, Biocellion asks users to provide their model specifics by filling the function body of pre-defined model routines. Using Biocellion, modelers without parallel computing expertise can efficiently exploit parallel computers with less effort than writing sequential programs from scratch. We simulate cell sorting, microbial patterning and a bacterial system in soil aggregate as case studies. Availability and implementation: Biocellion runs on x86 compatible systems with the 64 bit Linux operating system and is freely available for academic use. Visit http://biocellion.com for additional information. Contact: seunghwa.kang@pnnl.gov PMID:25064572

  14. Novel species and expanded distribution of ellipsoidal multicellular magnetotactic prokaryotes.

    PubMed

    Chen, Yi-ran; Zhang, Wen-yan; Zhou, Ke; Pan, Hong-miao; Du, Hai-jian; Xu, Cong; Xu, Jian-hong; Pradel, Nathalie; Santini, Claire-Lise; Li, Jin-hua; Huang, Hui; Pan, Yong-xin; Xiao, Tian; Wu, Long-fei

    2016-04-01

    Multicellular magnetotactic prokaryotes (MMPs) are a peculiar group of magnetotactic bacteria, each comprising approximately 10-100 cells of the same phylotype. Two morphotypes of MMP have been identified, including several species of globally distributed spherical mulberry-like MMPs (s-MMPs), and two species of ellipsoidal pineapple-like MMPs (e-MMPs) from China (Qingdao and Rongcheng cities). We recently collected e-MMPs from Mediterranean Sea sediments (Six-Fours-les-Plages) and Drummond Island, in the South China Sea. Phylogenetic analysis revealed that the MMPs from Six-Fours-les-Plages and the previously reported e-MMP Candidatus Magnetananas rongchenensis have 98.5% sequence identity and are the same species, while the MMPs from Drummond Island appear to be a novel species, having > 7.1% sequence divergence from the most closely related e-MMP, Candidatus Magnetananas tsingtaoensis. Identification of the novel species expands the distribution of e-MMPs to Tropical Zone. Comparison of nine physical and chemical parameters revealed that sand grain size and the content of inorganic nitrogen (nitrate, ammonium and nitrite) in the sediments from Rongcheng City and Six-Fours-les-Plages were similar, and lower than found for sediments from the other two sampling sites. The results of the study reveal broad diversity and wide distribution of e-MMPs. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Multicellularity and the Functional Interdependence of Motility and Molecular Transport

    NASA Astrophysics Data System (ADS)

    Solari, C.; Ganguly, S.; Kessler, J. O.; Michod, R.; Goldstein, R. E.

    2006-03-01

    Benefits, costs and requirements accompany the transition from motile totipotent unicellular organisms to multicellular organisms having cells specialized into reproductive (germ) and vegetative (sterile soma) functions such as motility. In flagellated colonial organisms such as the volvocalean green algae, organized beating by the somatic cells' flagella yields propulsion important in phototaxis and chemotaxis. It has not been generally appreciated that for the larger colonies, flagellar stirring of boundary layers and remote transport are fundamental for maintaining a sufficient rate of metabolite turnover, one not attainable by diffusive transport alone. We describe experiments that quantify the role of advective dynamics in enhancing productivity in germ-soma differentiated colonies. First, experiments with suspended deflagellated colonies of Volvox carteri show that forced advection improves productivity. Second, Particle Imaging Velocimetry of fluid motion around colonies reveals flow fields with very large characteristic velocities U extending to length scales comparable to the colony radius R. For a typical metabolite diffusion constant D, the Peclet number Pe=2UR/D 1, indicative of the dominance of advection over diffusion, with striking augmentation at the cell division stage.

  16. Multicellular contractility contributes to the emergence of mesothelioma nodules

    NASA Astrophysics Data System (ADS)

    Czirok, Andras

    Malignant pleural mesothelioma (MPM) nodules arise from the mesothelial lining of the pleural cavity by a poorly understood mechanism. We demonstrate that macroscopic multicellular aggregates, reminiscent of the MPM nodules found in patients, develop when MPM cell lines are cultured at high cell densities for several weeks. Surprisingly, the nodule-like aggregates do not arise by excessive local cell proliferation, but by myosin II-driven cell contractility. Contractile nodules contain prominent actin cables that can span several cells. Several features of the in vitro MPM nodule development can be explained by a computational model that assumes uniform and steady intercellular contractile forces within a monolayer of cells, and a mechanical load-dependent lifetime of cell-cell contacts. The model behaves as a self-tensioned Maxwell fluid and exhibits an instability that leads to pattern formation. Altogether, our findings suggest that inhibition of the actomyosin system may provide a hitherto not utilized therapeutic approach to affect MPM growth. NIH R01-GM102801.

  17. MicroRNAs in a multicellular green alga Volvox carteri.

    PubMed

    Li, Jingrui; Wu, Yang; Qi, Yijun

    2014-01-01

    microRNAs (miRNAs) have emerged as key components in the eukaryotic gene regulatory network. We and others have previously identified many miRNAs in a unicellular green alga, Chlamydomonas reinhardtii. To investigate whether miRNA-mediated gene regulation is a general mechanism in green algae and how miRNAs have been evolved in the green algal lineage, we examined small RNAs in Volvox carteri, a multicellular species in the same family with Chlamydomonas reinhardtii. We identified 174 miRNAs in Volvox, with many of them being highly enriched in gonidia or somatic cells. The targets of the miRNAs were predicted and many of them were subjected to miRNA-mediated cleavage in vivo, suggesting that miRNAs play regulatory roles in the biology of green algae. Our catalog of miRNAs and their targets provides a resource for further studies on the evolution, biological functions, and genomic properties of miRNAs in green algae.

  18. Origins of multicellular complexity: Volvox and the volvocine algae.

    PubMed

    Herron, Matthew D

    2016-03-01

    The collection of evolutionary transformations known as the 'major transitions' or 'transitions in individuality' resulted in changes in the units of evolution and in the hierarchical structure of cellular life. Volvox and related algae have become an important model system for the major transition from unicellular to multicellular life, which touches on several fundamental questions in evolutionary biology. The Third International Volvox Conference was held at the University of Cambridge in August 2015 to discuss recent advances in the biology and evolution of this group of algae. Here, I highlight the benefits of integrating phylogenetic comparative methods and experimental evolution with detailed studies of developmental genetics in a model system with substantial genetic and genomic resources. I summarize recent research on Volvox and its relatives and comment on its implications for the genomic changes underlying major evolutionary transitions, evolution and development of complex traits, evolution of sex and sexes, evolution of cellular differentiation and the biophysics of motility. Finally, I outline challenges and suggest future directions for research into the biology and evolution of the volvocine algae.

  19. Investigating acetaminophen hepatotoxicity in multi-cellular organotypic liver models.

    PubMed

    Orbach, Sophia M; Cassin, Margaret E; Ehrich, Marion F; Rajagopalan, Padmavathy

    2017-08-01

    In vivo studies clearly demonstrate the participation and subsequent death of non-parenchymal liver cells (NPCs) with corresponding hepatocyte effects. This results in a critical need to investigate how major liver cell types function cohesively during hepatotoxicity. However, virtually no studies replicate these phenomena in vitro. We report the design of multi-cellular three-dimensional (3D) organotypic liver models of primary rat hepatocytes, liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs). LSECs and KCs were separated from hepatocytes by a detachable membrane that emulates the physical and chemical properties of the Space of Disse. Acetaminophen (APAP)-induced changes to cellular function and phenotype were investigated. LSECs exhibited approximately 40% cell death at 20mM APAP. KCs exhibited decreased interleukin-10 and increased tumor necrosis factor-alpha and interferon-gamma secretion. The secretion of these proteins altered hepatocyte function and signaling. Both LSECs and KCs maintained phenotypic markers. At 20mM APAP, the 3D models exhibited aspartate aminotransferase to alanine aminotransferase ratios from 2.1-2.5 and 45% glutathione depletion, corresponding to what is seen in vivo. At 10 and 20mM APAP, the 3D models exhibited cell death, primarily through necrosis. Therefore, the 3D cultures described in this report demonstrate significant potential as realistic models for hepatotoxicity studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Identification of Dictyostelium G alpha genes expressed during multicellular development.

    PubMed Central

    Hadwiger, J A; Wilkie, T M; Strathmann, M; Firtel, R A

    1991-01-01

    Guanine nucleotide-binding protein (G protein)-mediated signal transduction constitutes a common mechanism by which cells receive and respond to a diverse set of environmental signals. Many of the signals involved in the developmental life cycle of the slime mold Dictyostelium have been postulated to be transduced by such pathways and, in some cases, these pathways have been demonstrated to be dependent on specific G proteins. Using the polymerase chain reaction, we have identified two additional Dictyostelium G alpha genes, G alpha 4 and G alpha 5, that are developmentally regulated. Transcripts from both of these genes are primarily expressed during the multicellular stages of development, suggesting possible roles in cell differentiation or morphogenesis. The entire G alpha 4 gene was sequenced and found to encode a protein consisting of 345 amino acids. The G alpha 4 subunit is homologous to other previously identified G alpha subunits, including the Dictyostelium G alpha 1 (43% identity) and G alpha 2 (41% identity) subunits. However, the G alpha 4 subunit contains some unusual sequence divergences in residues highly conserved among most eukaryotic G alpha subunits, suggesting that G alpha 4 may be a member of another class of G alpha subunits. Images PMID:1910174

  1. A framework to facilitate self-directed learning, assessment and supervision in midwifery practice: a qualitative study of supervisors' perceptions.

    PubMed

    Embo, M; Driessen, E; Valcke, M; van der Vleuten, C P M

    2014-08-01

    Self-directed learning is an educational concept that has received increasing attention. The recent workplace literature, however, reports problems with the facilitation of self-directed learning in clinical practice. We developed the Midwifery Assessment and Feedback Instrument (MAFI) as a framework to facilitate self-directed learning. In the present study, we sought clinical supervisors' perceptions of the usefulness of MAFI. Interviews with fifteen clinical supervisors were audio taped, transcribed verbatim and analysed thematically using Atlas-Ti software for qualitative data analysis. Four themes emerged from the analysis. (1) The competency-based educational structure promotes the setting of realistic learning outcomes and a focus on competency development, (2) instructing students to write reflections facilitates student-centred supervision, (3) creating a feedback culture is necessary to achieve continuity in supervision and (4) integrating feedback and assessment might facilitate competency development under the condition that evidence is discussed during assessment meetings. Supervisors stressed the need for direct observation, and instruction how to facilitate a self-directed learning process. The MAFI appears to be a useful framework to promote self-directed learning in clinical practice. The effect can be advanced by creating a feedback and assessment culture where learners and supervisors share the responsibility for developing self-directed learning. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Dupuytren's Contracture: Fibroblast Contraction?

    PubMed Central

    Gabbiani, Giulio; Majno, Guido

    1972-01-01

    In 6 cases of Dupuytren's disease and 1 of Ledderhose's disease, the nodules of the palmar and plantar aponeurosis were examined by light and electron microscopy. The cells composing these nodules, presumably fibroblasts, showed three significant ultrastructural features: (1) a fibrillar system similar to that of smooth muscle cells; (2) nuclear deformations such as are found in contracted cells, the severest being recognizable by light microscopy (cross-banded nuclei); (3) cell-to-cell and cell-to-stroma attachments. Based on these data and on recent information about the biology of the fibroblasts, it is suggested that these cells are fibroblasts that have modulated into contractile cells (myofibroblasts), and that their contraction plays a role in the pathogenesis of the contracture observed clinically. ImagesFig 10Fig 5Fig 11Fig 6 and 7Fig 8Fig 1Fig 2Fig 9Fig 3Fig 4 PMID:5009249

  3. Improved use of a public good selects for the evolution of undifferentiated multicellularity.

    PubMed

    Koschwanez, John H; Foster, Kevin R; Murray, Andrew W

    2013-04-02

    We do not know how or why multicellularity evolved. We used the budding yeast, Saccharomyces cerevisiae, to ask whether nutrients that must be digested extracellularly select for the evolution of undifferentiated multicellularity. Because yeast use invertase to hydrolyze sucrose extracellularly and import the resulting monosaccharides, single cells cannot grow at low cell and sucrose concentrations. Three engineered strategies overcame this problem: forming multicellular clumps, importing sucrose before hydrolysis, and increasing invertase expression. We evolved populations in low sucrose to ask which strategy they would adopt. Of 12 successful clones, 11 formed multicellular clumps through incomplete cell separation, 10 increased invertase expression, none imported sucrose, and 11 increased hexose transporter expression, a strategy we had not engineered. Identifying causal mutations revealed genes and pathways, which frequently contributed to the evolved phenotype. Our study shows that combining rational design with experimental evolution can help evaluate hypotheses about evolutionary strategies. DOI:http://dx.doi.org/10.7554/eLife.00367.001.

  4. Observation of multicellular spinning behavior of Proteus mirabilis by atomic force microscopy and multifunctional microscopy.

    PubMed

    Liu, Yanxia; Deng, Yuanxin; Luo, Shuxiu; Deng, Yu; Guo, Linming; Xu, Weiwei; Liu, Lei; Liu, Junkang

    2014-01-01

    This study aimed to observe the multicellular spinning behavior of Proteus mirabilis by atomic force microscopy (AFM) and multifunctional microscopy in order to understand the mechanism underlying this spinning movement and its biological significance. Multifunctional microscopy with charge-coupled device (CCD) and real-time AFM showed changes in cell structure and shape of P. mirabilis during multicellular spinning movement. Specifically, the morphological characteristics of P. mirabilis, multicellular spinning dynamics, and unique movement were observed. Our findings indicate that the multicellular spinning behavior of P. mirabilis may be used to collect nutrients, perform colonization, and squeeze out competitors. The movement characteristics of P. mirabilis are vital to the organism's biological adaptability to the surrounding environment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Requirements for the self-directed replication of flock house virus RNA 1.

    PubMed Central

    Ball, L A

    1995-01-01

    The larger segment (RNA 1) of the bipartite, positive-sense RNA genome of the nodavirus flock house virus encodes the viral RNA-dependent RNA polymerase. Two nonstructural viral proteins are made during the self-directed replication of this RNA: protein A (110 kDa), the translation product of RNA 1 itself, and protein B (11 kDa), the translation product of a subgenomic RNA (RNA 3) that is produced from RNA 1 during replication. To examine the roles of these proteins in RNA replication, specialized T7 transcription plasmids that contained wild-type or mutant copies of flock house virus RNA 1 cDNA were constructed and used in cells infected with the vaccinia virus-T7 RNA polymerase recombinant to make full-length transcripts that directed their own replication. Sequences in the primary transcripts that extended beyond the ends of the authentic RNA 1 sequence inhibited self-directed RNA replication, but plasmids that were constructed to minimize these terminal extensions produced primary transcripts that replicated as abundantly as authentic RNA 1. Truncation or mutation of the open reading frame for protein A eliminated self-directed replication, although the mutant RNA 1 remained a competent template for replication by wild-type protein A supplied in trans. These results showed that protein A was essential for RNA replication and that the process was not inseparably coupled to complete translation of the template. In contrast, protein B could be eliminated without inhibiting replication by mutations that disrupted the second of the two overlapping open reading frames on RNA 3. Furthermore, a mutant of RNA 1 in which the first nucleotide of the RNA 3 region was changed from G to U replicated at levels as high as those of the wild type without making either RNA 3 or protein B. However, diminishing replication levels were observed during subsequent replicative passages of RNA from both the mutants that could not make protein B. Roles for this protein that could account

  6. Activated hepatic stellate cells play pivotal roles in hepatocellular carcinoma cell chemoresistance and migration in multicellular tumor spheroids

    PubMed Central

    Song, Yeonhwa; Kim, Se-hyuk; Kim, Kang Mo; Choi, Eun Kyung; Kim, Joon; Seo, Haeng Ran

    2016-01-01

    Most Hepatocellular carcinoma (HCC) are resistant to conventional chemotherapeutic agents and remain an unmet medical need. Recently, multiple studies on the crosstalk between HCC and their tumor microenvironment have been conducted to overcome chemoresistance in HCC. In this study, we formed multicellular tumor spheroids (MCTS) to elucidate the mechanisms of environment-mediated chemoresistance in HCC. We observed that hepatic stellate cells (HSCs) in MCTS significantly increased the compactness of spheroids and exhibited strong resistance to sorafenib and cisplatin relative to other types of stromal cells. Increased collagen 1A1 (COL1A1) expression was apparent in activated HSCs but not in fibroblasts or vascular endothelial cells in MCTS. Additionally, COL1A1 deficiency, which was increased by co-culture with HSCs, decreased the cell-cell interactions and thereby increased the therapeutic efficacy of anticancer therapies in MCTS. Furthermore, losartan, which can inhibit collagen I synthesis, attenuated the compactness of spheroids and increased the therapeutic efficacy of anticancer therapies in MCTS. Meanwhile, activated HSCs facilitated HCC migration by upregulating matrix metallopeptidase 9 (MMP9) in MCTS. Collectively, crosstalk between HCC cells and HSCs promoted HCC chemoresistance and migration by increasing the expression of COL1A1 and MMP9 in MCTS. Hence, targeting HSCs might represent a promising therapeutic strategy for liver cancer therapy. PMID:27853186

  7. The development and structure of thick-walled, multicellular, aerial spores in Diheterospora chlamydosporia (=Verticillium chlamydosporium).

    PubMed

    Cambell, W P; Griffiths, D A

    1975-07-01

    The aerial, thick-walled spores in Diheterospara chlamydosporia arose as terminal swellings on erect hyphae. Repeated septation of the continuously swelling spore resulted in a multicellular structure. Immediately after the onset of septation secondary wall material was laid down between the two-layered primary wall and the plasmalemma. The presence of secondary wall material indicates that the multicellular spore is a dictyochlamydospore and not an aleuriospore. The relationship between chlamydospores and aleuriospores in other fungi is discussed.

  8. Evolution of multicellularity coincided with increased diversification of cyanobacteria and the Great Oxidation Event

    PubMed Central

    Schirrmeister, Bettina E.; de Vos, Jurriaan M.; Antonelli, Alexandre; Bagheri, Homayoun C.

    2013-01-01

    Cyanobacteria are among the most diverse prokaryotic phyla, with morphotypes ranging from unicellular to multicellular filamentous forms, including those able to terminally (i.e., irreversibly) differentiate in form and function. It has been suggested that cyanobacteria raised oxygen levels in the atmosphere around 2.45–2.32 billion y ago during the Great Oxidation Event (GOE), hence dramatically changing life on the planet. However, little is known about the temporal evolution of cyanobacterial lineages, and possible interplay between the origin of multicellularity, diversification of cyanobacteria, and the rise of atmospheric oxygen. We estimated divergence times of extant cyanobacterial lineages under Bayesian relaxed clocks for a dataset of 16S rRNA sequences representing the entire known diversity of this phylum. We tested whether the evolution of multicellularity overlaps with the GOE, and whether multicellularity is associated with significant shifts in diversification rates in cyanobacteria. Our results indicate an origin of cyanobacteria before the rise of atmospheric oxygen. The evolution of multicellular forms coincides with the onset of the GOE and an increase in diversification rates. These results suggest that multicellularity could have played a key role in triggering cyanobacterial evolution around the GOE. PMID:23319632

  9. Evolution of multicellularity coincided with increased diversification of cyanobacteria and the Great Oxidation Event.

    PubMed

    Schirrmeister, Bettina E; de Vos, Jurriaan M; Antonelli, Alexandre; Bagheri, Homayoun C

    2013-01-29

    Cyanobacteria are among the most diverse prokaryotic phyla, with morphotypes ranging from unicellular to multicellular filamentous forms, including those able to terminally (i.e., irreversibly) differentiate in form and function. It has been suggested that cyanobacteria raised oxygen levels in the atmosphere around 2.45-2.32 billion y ago during the Great Oxidation Event (GOE), hence dramatically changing life on the planet. However, little is known about the temporal evolution of cyanobacterial lineages, and possible interplay between the origin of multicellularity, diversification of cyanobacteria, and the rise of atmospheric oxygen. We estimated divergence times of extant cyanobacterial lineages under Bayesian relaxed clocks for a dataset of 16S rRNA sequences representing the entire known diversity of this phylum. We tested whether the evolution of multicellularity overlaps with the GOE, and whether multicellularity is associated with significant shifts in diversification rates in cyanobacteria. Our results indicate an origin of cyanobacteria before the rise of atmospheric oxygen. The evolution of multicellular forms coincides with the onset of the GOE and an increase in diversification rates. These results suggest that multicellularity could have played a key role in triggering cyanobacterial evolution around the GOE.

  10. Self-directed learning and portfolio development for nurses: developing workbooks as a facilitative tool.

    PubMed

    Cleary, Michelle; Freeman, Adele

    2005-09-01

    Workbooks are often used for discipline-specific learning in academic institutions but there is growing recognition of their potential usefulness in the clinical setting to promote learning and professional development. The purpose of this paper is to share some tips/guidelines for those clinical staff interested in developing self-directed learning programs using a workbook approach. Combined with skilled facilitation, custom designed workbooks based on adult learning theories can enhance skills and encourage portfolio development in the clinical setting. This cost and time effective approach utilises existing resources to cater to diverse needs and topics, building sustainable collaborations. This paper will argue that the proposed program has the potential to contribute to healthcare improvement by promoting skill development amongst staff and contributing to evidence-based practice.

  11. The effect of self-directed learning abilities of student nurses on success in Turkey.

    PubMed

    Avdal, Elif Ünsal

    2013-08-01

    SDL-self-directed learning is a learning method used increasingly in adult education. This study was carried out as an instructive effort to examine the effects of SDL on the success of students from nursing school. The sample of this study was composed of 220 students attending in Nursing School of Dokuz Eyül University during the fall semester of 2006. SDL scale including 40 questions was used to obtain the data. Kocaman et al. verified and validated the reliability of scale in Turkey. The data was evaluated by using Pearson correlation analysis. As a result of research, a positive meaningful average relation was found between the points of SDL and success of the students. (p<0.01, r: .60).

  12. A Quasi-Linear Behavioral Model and an Application to Self-Directed Learning

    NASA Technical Reports Server (NTRS)

    Ponton, Michael K.; Carr, Paul B.

    1999-01-01

    A model is presented that describes the relationship between one's knowledge of the world and the concomitant personal behaviors that serve as a mechanism to obtain desired outcomes. Integrated within this model are the differing roles that outcomes serve as motivators and as modifiers to one's worldview. The model is dichotomized between general and contextual applications. Because learner self-directedness (a personal characteristic) involves cognition and affection while self-directed learning (a pedagogic process) encompasses conation, behavior and introspection, the model can be dichotomized again in another direction. Presented also are the roles that cognitive motivation theories play in moving an individual through this behavioral model and the roles of wishes, self-efficacy, opportunity and self-influence.

  13. Aging and health: Self-efficacy for Self-direction in Health Scale.

    PubMed

    Oliveira, Albertina L; Silva, José T; Lima, Margarida P

    2016-07-04

    To validate the Escala de Autoeficácia para a Autodireção na Saúde (EAAS - Self-efficacy for Self-direction in Health Scale). Non-experimental quantitative study of EAAS validation, by confirmatory factorial analyses, evaluating a sample of 508 older adults from the north and the center of Portugal with mean age of 71.67 (from 51 to 96 years), to whom the Self-efficacy for Self-direction in Health Scale, the Rosenberg Self-esteem Scale, the Positive and Negative Affect Schedule, the Satisfaction with Life Scale, and the Instrumental Activities of Daily Living Scale were applied. The EAAS was developed from the theoretical constructs of self-efficacy and from self-directed learning within the PALADIN European project framework, aiming to develop an instrument able to assess the extent to which older adults take good care of their health. The internal consistency was 0.87 (Cronbach's alpha) and confirmatory factorial analyses enabled to find a model near the one theoretically proposed, indicating a structure consisting of four dimensions: physical exercise, healthy diet, engaging in health-related learning, and visits to health professionals. From the psychometric point of view, the model in four factors showed quite satisfactory fit indicators. The Self-efficacy for Self-direction in Health Scale, with 16 items, is adequate to evaluate to what extent older adults have confidence in their ability to take care of their own health, with high degree of autonomy. Validar a Escala de Autoeficácia para a Autodireção no domínio da Saúde (EAAS). Estudo quantitativo não experimental de validação da EAAS, por meio de análises fatoriais confirmatórias, avaliando amostra de 508 seniores e idosos provenientes das regiões Norte e Centro de Portugal com média etária de 71.67 (51 a 96 anos), a quem foram aplicadas a Escala de Autoeficácia para a Autodireção na Saúde, a Escala de Autoestima de Rosenberg, a Escala de Afeto Positivo e Afeto Negativo, a Escala de

  14. Improving workplace safety training using a self-directed CPR-AED learning program.

    PubMed

    Mancini, Mary E; Cazzell, Mary; Kardong-Edgren, Suzan; Cason, Carolyn L

    2009-04-01

    Adequate training in cardiopulmonary resuscitation (CPR) and use of an automated external defibrillator (AED) is an important component of a workplace safety training program. Barriers to traditional in-classroom CPR-AED training programs include time away from work to complete training, logistics, learner discomfort over being in a classroom setting, and instructors who include information irrelevant to CPR. This study evaluated differences in CPR skills performance between employees who learned CPR using a self-directed learning (SDL) kit and employees who attended a traditional instructor-led course. The results suggest that the SDL kit yields learning outcomes comparable to those obtained with traditional instructor-led courses and is a more time-efficient tool for CPR-AED training. Furthermore, the SDL kit overcomes many of the barriers that keep individuals from learning CPR and appears to contribute to bystanders' confidently attempting resuscitation.

  15. Hollow Superparamagnetic Microballoons from Lifelike, Self-Directed Pickering Emulsions Based on Patchy Nanoparticles.

    PubMed

    Granath, Tim; Sanchez-Sanchez, Angela; Shmeliov, Aleksey; Nicolosi, Valeria; Fierro, Vanessa; Celzard, Alain; Mandel, Karl

    2016-11-22

    Herein, the formation of hollow microballoons derived from superparamagnetic iron oxide nanoparticles with silica patches is reported. Depending on the experimental conditions, single- or multishelled superparamagnetic microballoons as well as multivesicular structures were obtained. We show how such structural changes follow a lifelike process that is based on self-directing Pickering emulsions. We further demonstrate that the key toward the formation of such complex architectures is the patchy nature of the nanoparticles. Interestingly, no well-defined ordering of patches on the particles surface is required, unlike what theorists formerly predicted. The resultant hollow microballoons may be turned into hollow carbonaceous magnetic microspheres by simple pyrolysis. This opens the way to additional potential applications for such ultralightweight (density: 0.16 g·cm(-3)) materials.

  16. [Vocational choice and career planning. Spanish adaptation of Holland's Self-Directed Search (SDS-R)].

    PubMed

    Martínez Vicente, José Manuel; Valls Fernández, Federico

    2006-02-01

    The Self-Directed Search is a career-planning guide that works similarly to a vocational and professional interests inventory. A preliminary study allows detection of 68 ítems that need to be rectified, since they do not meet psychometric and semantic criteria. The current study demonstrates reliability and validity of the new adaptation. It is applied to a sample of 1460 subjects from different educational levels. As for reliability, the discrimination index of the items and internal consistency of the scales have improved. Additionally, procedures performed to verify validity (content, construct and concurrent) demonstrate that the instrument has acceptable validity. On balance, we can conclude that the instrument has sufficient scientific and technical credibility for application to the Spanish population.

  17. Spatial self-organization in hybrid models of multicellular adhesion

    NASA Astrophysics Data System (ADS)

    Bonforti, Adriano; Duran-Nebreda, Salva; Montañez, Raúl; Solé, Ricard

    2016-10-01

    Spatial self-organization emerges in distributed systems exhibiting local interactions when nonlinearities and the appropriate propagation of signals are at work. These kinds of phenomena can be modeled with different frameworks, typically cellular automata or reaction-diffusion systems. A different class of dynamical processes involves the correlated movement of agents over space, which can be mediated through chemotactic movement or minimization of cell-cell interaction energy. A classic example of the latter is given by the formation of spatially segregated assemblies when cells display differential adhesion. Here, we consider a new class of dynamical models, involving cell adhesion among two stochastically exchangeable cell states as a minimal model capable of exhibiting well-defined, ordered spatial patterns. Our results suggest that a whole space of pattern-forming rules is hosted by the combination of physical differential adhesion and the value of probabilities modulating cell phenotypic switching, showing that Turing-like patterns can be obtained without resorting to reaction-diffusion processes. If the model is expanded allowing cells to proliferate and die in an environment where diffusible nutrient and toxic waste are at play, different phases are observed, characterized by regularly spaced patterns. The analysis of the parameter space reveals that certain phases reach higher population levels than other modes of organization. A detailed exploration of the mean-field theory is also presented. Finally, we let populations of cells with different adhesion matrices compete for reproduction, showing that, in our model, structural organization can improve the fitness of a given cell population. The implications of these results for ecological and evolutionary models of pattern formation and the emergence of multicellularity are outlined.

  18. Spatial self-organization in hybrid models of multicellular adhesion.

    PubMed

    Bonforti, Adriano; Duran-Nebreda, Salva; Montañez, Raúl; Solé, Ricard

    2016-10-01

    Spatial self-organization emerges in distributed systems exhibiting local interactions when nonlinearities and the appropriate propagation of signals are at work. These kinds of phenomena can be modeled with different frameworks, typically cellular automata or reaction-diffusion systems. A different class of dynamical processes involves the correlated movement of agents over space, which can be mediated through chemotactic movement or minimization of cell-cell interaction energy. A classic example of the latter is given by the formation of spatially segregated assemblies when cells display differential adhesion. Here, we consider a new class of dynamical models, involving cell adhesion among two stochastically exchangeable cell states as a minimal model capable of exhibiting well-defined, ordered spatial patterns. Our results suggest that a whole space of pattern-forming rules is hosted by the combination of physical differential adhesion and the value of probabilities modulating cell phenotypic switching, showing that Turing-like patterns can be obtained without resorting to reaction-diffusion processes. If the model is expanded allowing cells to proliferate and die in an environment where diffusible nutrient and toxic waste are at play, different phases are observed, characterized by regularly spaced patterns. The analysis of the parameter space reveals that certain phases reach higher population levels than other modes of organization. A detailed exploration of the mean-field theory is also presented. Finally, we let populations of cells with different adhesion matrices compete for reproduction, showing that, in our model, structural organization can improve the fitness of a given cell population. The implications of these results for ecological and evolutionary models of pattern formation and the emergence of multicellularity are outlined.

  19. Symbiotic Cell Differentiation and Cooperative Growth in Multicellular Aggregates

    PubMed Central

    Yamagishi, Jumpei F; Saito, Nen; Kaneko, Kunihiko

    2016-01-01

    As cells grow and divide under a given environment, they become crowded and resources are limited, as seen in bacterial biofilms and multicellular aggregates. These cells often show strong interactions through exchanging chemicals, as evident in quorum sensing, to achieve mutualism and division of labor. Here, to achieve stable division of labor, three characteristics are required. First, isogenous cells differentiate into several types. Second, this aggregate of distinct cell types shows better growth than that of isolated cells without interaction and differentiation, by achieving division of labor. Third, this cell aggregate is robust with respect to the number distribution of differentiated cell types. Indeed, theoretical studies have thus far considered how such cooperation is achieved when the ability of cell differentiation is presumed. Here, we address how cells acquire the ability of cell differentiation and division of labor simultaneously, which is also connected with the robustness of a cell society. For this purpose, we developed a dynamical-systems model of cells consisting of chemical components with intracellular catalytic reaction dynamics. The reactions convert external nutrients into internal components for cellular growth, and the divided cells interact through chemical diffusion. We found that cells sharing an identical catalytic network spontaneously differentiate via induction from cell-cell interactions, and then achieve division of labor, enabling a higher growth rate than that in the unicellular case. This symbiotic differentiation emerged for a class of reaction networks under the condition of nutrient limitation and strong cell-cell interactions. Then, robustness in the cell type distribution was achieved, while instability of collective growth could emerge even among the cooperative cells when the internal reserves of products were dominant. The present mechanism is simple and general as a natural consequence of interacting cells with

  20. Modeling of Oxygen Transport Across Tumor Multicellular Layers

    PubMed Central

    Braun, Rod D.; Beatty, Alexis L.

    2007-01-01

    Purpose Tumor oxygen level plays a major role in the response of tumors to different treatments. The purpose of this study was to develop a method of determining oxygen transport properties in a recently developed 3-D model of tumor parenchyma, the multicellular layer (MCL). Methods OCM-1 human choroidal melanoma cells were grown as 3-D MCL on collagen-coated culture plate inserts. A recessed-cathode oxygen microelectrode was used to measure oxygen tension (PO2) profiles across 8 different MCL from the free surface to the insert membrane. The profiles were fitted to four different one-dimensional diffusion models: 1-, 2-, and 3-region models with uniform oxygen consumption (q) in each region and a modified 3-region model with a central region where q=0 and PO2=0. Results Depending upon the presence of a central region of anoxia, the PO2 profiles were fitted best by either the two-region model or the modified 3-region model. Consumption of tumor cells near the insert membrane was higher than that of cells close to the free surface (33.1 ± 13.6 x 10−4 vs. 11.8 ± 6.7 x 10−4 mm Hg/μm2, respectively). Conclusions The model is useful for determining oxygenation and consumption in MCL, especially for cell lines that cannot be grown as spheroids. In the future, this model will permit the study of parameters important in tumor oxygenation in vitro. PMID:17196225

  1. Evaluation of interstitial protein delivery in multicellular layers model.

    PubMed

    Kim, Soo-Yeon; Kim, Tae Hyung; Choi, Jong Hoon; Lee, Kang Choon; Park, Ki Dong; Lee, Seung-Jin; Kuh, Hyo-Jeong

    2012-03-01

    The limited efficacy of anticancer protein drugs is related to their poor distribution in tumor tissue. We examined interstitial delivery of four model proteins of different molecular size and bioaffinity in multicellular layers (MCL) of human cancer cells. Model proteins were tumor necrosis factor-related apoptosis-including ligand (TRAIL), cetuximab, RNase A, and IgG. MCLs were cultured in Transwell inserts, exposed to drugs, then cryo-sectioned for image acquisition using fluorescence microscopy (fluorescent dye-labeled TRAIL, RNase A, IgG) or immunohistochemistry (cetuximab). TRAIL and cetuximab showed partial penetration into MCLs, whereas RNase A and IgG showed insignificant penetration. At 10-fold higher dose, a significant increase in penetration was observed for IgG only, while cetuximab showed an intense accumulation limited to the front layers. PEGylated TRAIL and RNase A formulated in a heparin-Pluronic (HP) nanogel showed significantly improved penetration attributable to increased stability and extracellular matrix binding, respectively. IgG penetration was significantly enhanced with paclitaxel pretreatment as a penetration enhancer. The present study suggests that MCL culture may be useful in evaluation of protein delivery in the tumor interstitium. Four model proteins showed limited interstitial penetration in MCL cultures. Bioaffinity, rather than molecular size, seems to have a positive effect on tissue penetration, although high binding affinity may lead to sequestration in the front cell layers. Polymer conjugation and nanoformulation, such as PEGylation and HP nanogel, or use of penetration enhancers are potential strategies to increase interstitial delivery of anticancer protein drugs.

  2. Enhancing self-directed learning among Italian nursing students: A pre- and post-intervention study.

    PubMed

    Cadorin, L; Rei, A; Dante, A; Bulfone, T; Viera, G; Palese, A

    2015-06-01

    In accordance with Knowles's theory, self-directed learning (SDL) may be improved with tutorial strategies focused on guided reflection and critical analysis of the learning process. No evidence on effects on SDL abilities of different tutorial strategies offered to nursing students during the 1st clinical experience is available. To evaluate the effect of different tutorial strategies offered to nursing students on their SDL abilities. A pre-post intervention non-equivalent control group design was adopted in 2013. For the treatment group, structured and intensive tutorial interventions including different strategies such as briefing, debriefing, peer support, Socratic questioning, performed by university tutors were offered during the 1st clinical experience; for the control group, unstructured and non-intensive tutorial strategies were instead offered. Two Bachelor of Nursing Degree. Students awaiting their clinical experience (n=238) were the target sample. Those students who have completed the pre- and the post-intervention evaluation (201; 84.4%) were included in the analysis. SDL abilities were measured with the SRSSDL_ITA (Self Rating Scale of Self Directed Learning-Italian Version). A multiple linear regression analysis was developed to explore the predictive effect of individual, contextual and intervention variables. Three main factors explained the 36.8% of the adjusted variance in SDL scores have emerged: a) having received a lower clinical nurse-to-student supervision (B 9.086, β 2.874), b) having received higher level and structured tutorial intervention by university tutors (B 8.011, β 2.741), and c) having reported higher SDL scores at the baseline (B .550, β .556). A lower clinical nurse-to-student ratio (1:4), accompanied by unstructured and non-intensive tutorial intervention adopted by university tutors, seemed to be equivalent to an intensive clinical supervision (1:1) accompanied by higher level and structured tutorial strategies activated

  3. Constructive, collaborative, contextual, and self-directed learning in surface anatomy education.

    PubMed

    Bergman, Esther M; Sieben, Judith M; Smailbegovic, Ida; de Bruin, Anique B H; Scherpbier, Albert J J A; van der Vleuten, Cees P M

    2013-01-01

    Anatomy education often consists of a combination of lectures and laboratory sessions, the latter frequently including surface anatomy. Studying surface anatomy enables students to elaborate on their knowledge of the cadaver's static anatomy by enabling the visualization of structures, especially those of the musculoskeletal system, move and function in a living human being. A recent development in teaching methods for surface anatomy is body painting, which several studies suggest increases both student motivation and knowledge acquisition. This article focuses on a teaching approach and is a translational contribution to existing literature. In line with best evidence medical education, the aim of this article is twofold: to briefly inform teachers about constructivist learning theory and elaborate on the principles of constructive, collaborative, contextual, and self-directed learning; and to provide teachers with an example of how to implement these learning principles to change the approach to teaching surface anatomy. Student evaluations of this new approach demonstrate that the application of these learning principles leads to higher student satisfaction. However, research suggests that even better results could be achieved by further adjustments in the application of contextual and self-directed learning principles. Successful implementation and guidance of peer physical examination is crucial for the described approach, but research shows that other options, like using life models, seem to work equally well. Future research on surface anatomy should focus on increasing the students' ability to apply anatomical knowledge and defining the setting in which certain teaching methods and approaches have a positive effect. Copyright © 2012 American Association of Anatomists.

  4. Educational strategies associated with development of problem-solving, critical thinking, and self-directed learning.

    PubMed

    Hendricson, William D; Andrieu, Sandra C; Chadwick, D Gregory; Chmar, Jacqueline E; Cole, James R; George, Mary C; Glickman, Gerald N; Glover, Joel F; Goldberg, Jerold S; Haden, N Karl; Meyerowitz, Cyril; Neumann, Laura; Pyle, Marsha; Tedesco, Lisa A; Valachovic, Richard W; Weaver, Richard G; Winder, Ronald L; Young, Stephen K; Kalkwarf, Kenneth L

    2006-09-01

    This article was developed for the Commission on Change and Innovation in Dental Education (CCI), established by the American Dental Education Association. CCI was created because numerous organizations within organized dentistry and the educational community have initiated studies or proposed modifications to the process of dental education, often working to achieve positive and desirable goals but without coordination or communication. The fundamental mission of CCI is to serve as a focal meeting place where dental educators and administrators, representatives from organized dentistry, the dental licensure community, the Commission on Dental Accreditation, the ADA Council on Dental Education and Licensure, and the Joint Commission on National Dental Examinations can meet and coordinate efforts to improve dental education and the nation's oral health. One of the objectives of the CCI is to provide guidance to dental schools related to curriculum design. In pursuit of that objective, this article summarizes the evidence related to this question: What are educational best practices for helping dental students acquire the capacity to function as an entry-level general dentist or to be a better candidate to begin advanced studies? Three issues are addressed, with special emphasis on the third: 1) What constitutes expertise, and when does an individual become an expert? 2) What are the differences between novice and expert thinking? and 3) What educational best practices can help our students acquire mental capacities associated with expert function, including critical thinking and self-directed learning? The purpose of this review is to provide a benchmark that faculty and academic planners can use to assess the degree to which their curricula include learning experiences associated with development of problem-solving, critical thinking, self-directed learning, and other cognitive skills necessary for dental school graduates to ultimately become expert performers as

  5. Study guides: effective tools to improve self-directed learning skills of medical students.

    PubMed

    Khabaz Mafinejad, Mahboobeh; Aghili, Rokhsareh; Emami, Zahra; Malek, Mojtaba; Baradaran, Hamidreza; Taghavinia, Mansoureh; Khamseh, Mohammad E

    2014-01-01

    In medicine, there is a rapid development of a knowledge base. Medical professionals need to sustain and advance their competence to practice in response to these varieties. So, there is increased interest in self-directed learning methods. Study guides can make a major contribution to self-directed learning. This study was carried out to evaluate the effect of study guides on improving self-learning skills of medical students in the Iran University of Medical Sciences (IUMS). In this quasi-experimental study, 46 medical students were randomly assigned into two groups; the intervention group and the control group. Both groups participated in a diagnostic test at the beginning of the course (pre-test). The same test was taken at the end of the course (post-test). The intervention group was provided with study guides on thyroid disorders and diabetes. Meanwhile, they continued their routine clinical training. The control group was only involved in the conventional training program. Students in the intervention group were also asked to complete a designed questionnaire in regard to their attitude toward the study guides. At enrollment, there was no statistically significant difference between the two groups. The mean scores of the pre-test for the control group and the intervention group were 6.18 and 6.13 respectively (P=0.9). In the post-test, the mean score of the students in the intervention group was considerably higher: 9.25 vs. 12 (P=0.002). The students in the intervention group found the study guides useful. The study guides were potentially effective in motivating self-learning in this group of medical students and had a remarkable effect on their final score.

  6. Changes in self-directed learning readiness in dental students: a mixed-methods study.

    PubMed

    Premkumar, Kalyani; Pahwa, Punam; Banerjee, Ankona; Baptiste, Kellen; Bhatt, Hitesh; Lim, Hyun J

    2014-06-01

    The purpose of this study was to identify changes in dental students' self-directed learning (SDL) readiness during their education. Guglielmino's SDL readiness scale (SDLRS) was completed at admission by dental students at the University of Saskatchewan and at the end of each year of training. The response rates varied from year to year. Between twenty-seven and thirty students completed the questionnaire each year at admission (93-100 percent of the entering class). The numbers of participants were lower in succeeding years: numbers used for analysis ranged from eleven to twenty-six; years in which fewer than eleven students participated were not included in the analysis. At admission, the students' mean SDLRS score was 228.98 (on a scale from 58 to 290, with 290 the highest); this score was higher than that of the average adult population (214±25.59). There was no significant effect of years of predental education, prior unsuccessful applications to dental school, interview scores, age, or admission test scores. There was a significant drop in SDLRS scores at the end of the first year for most of the cohorts (p<0.001). In addition to the questionnaire part of the study, two instructors and five first- and second-year students participated in focus groups. Those results showed that the individuals defined SDL narrowly and had similar perceptions of curricular factors that affect SDL readiness. The drop in scores one year after admission and lack of change with increased training suggests that current educational interventions may require re-examination and alteration to those that promote self-direction.

  7. The strategic use of lecture recordings to facilitate an active and self-directed learning approach.

    PubMed

    Topale, Luminica

    2016-08-12

    New learning technologies have the capacity to dramatically impact how students go about learning and to facilitate an active, self-directed learning approach. In U. S. medical education, students encounter a large volume of content, which must be mastered at an accelerated pace. The added pressure to excel on the USMLE Step 1 licensing exam and competition for residency placements, require that students adopt an informed approach to the use of learning technologies so as to enhance rather than to detract from the learning process. The primary aim of this study was to gain a better understanding of how students were using recorded lectures in their learning and how their study habits have been influenced by the technology. Survey research was undertaken using a convenience sample. Students were asked to voluntarily participate in an electronic survey comprised of 27 closed ended, multiple choice questions, and one open ended item. The survey was designed to explore students' perceptions of how recorded lectures affected their choices regarding class participation and impacted their learning and to gain an understanding of how recorded lectures facilitated a strategic, active learning process. Findings revealed that recorded lectures had little influence on students' choices to participate, and that the perceived benefits of integrating recorded lectures into study practices were related to their facilitation of and impact on efficient, active, and self-directed learning. This study was a useful investigation into how the availability of lecture capture technology influenced medical students' study behaviors and how students were making valuable use of the technology as an active learning tool.

  8. Medical student preferences for self-directed study resources in gross anatomy.

    PubMed

    Choi-Lundberg, Derek L; Low, Tze Feng; Patman, Phillip; Turner, Paul; Sinha, Sankar N

    2016-01-01

    Gross anatomy instruction in medical curricula involve a range of resources and activities including dissection, prosected specimens, anatomical models, radiological images, surface anatomy, textbooks, atlases, and computer-assisted learning (CAL). These resources and activities are underpinned by the expectation that students will actively engage in self-directed study (SDS) to enhance their knowledge and understanding of anatomy. To gain insight into preclinical versus clinical medical students' preferences for SDS resources for learning gross anatomy, and whether these vary on demographic characteristics and attitudes toward anatomy, students were surveyed at two Australian medical schools, one undergraduate-entry and the other graduate-entry. Lecture/tutorial/practical notes were ranked first by 33% of 156 respondents (mean rank ± SD, 2.48 ± 1.38), textbooks by 26% (2.62 ± 1.35), atlases 20% (2.80 ± 1.44), videos 10% (4.34 ± 1.68), software 5% (4.78 ± 1.50), and websites 4% (4.24 ± 1.34). Among CAL resources, Wikipedia was ranked highest. The most important factor in selecting CAL resources was cost (ranked first by 46%), followed by self-assessment, ease of use, alignment with curriculum, and excellent graphics (each 6-9%). Compared with preclinical students, clinical students ranked software and Acland's Video Atlas of Human Anatomy higher and felt radiological images were more important in selecting CAL resources. Along with other studies reporting on the quality, features, and impact on learning of CAL resources, the diversity of students' preferences and opinions on usefulness and ease of use reported here can help guide faculty in selecting and recommending a range of CAL and other resources to their students to support their self-directed study.

  9. Self-directed Mindfulness Training and Improvement in Blood Pressure, Migraine Frequency, and Quality of Life

    PubMed Central

    Rempe, Margaret; Bradley, Ryan

    2013-01-01

    Background: Interest in case studies has undergone a resurgence concurrent with increasing prioritization of illustrations of patient-centered care. However, substantial inclusion of the patient in these reports remains limited. Here, a doctor and patient collaborate to present her case report of self-directed mindfulness training and the subsequent changes in blood pressure, migraine frequency, and quality of life. Methods: After receiving encouragement from her naturopathic doctor, the patient initiated an 8-week program in mindfulness training following the Kabat-Zinn protocol and logged her daily blood pressure and symptoms before and after meditation sessions over an 11-week period. Results: Patient-reported outcomes included decreased perceived stress, increased focus, and a newfound sense of centeredness and calm. Changes in objective outcomes were clinically and statistically significant, including reductions in mean systolic and diastolic blood pressure between week 1 and week 11 (P = .0001 and P = .0004 for systolic and diastolic, respectively, by paired, 2-sided t-tests). Self-reported frequency of chronic migraine was also reduced. Critical to the patient's success was that mindfulness training was first approached in a simple, accessible manner prior to embarking on a deeper, extended experience. Discussion and Conclusion: Self-directed mindfulness training can have a meaningful impact on both subjective and objective health outcomes. It may take years of encouragement from a healthcare provider before a patient is ready to adopt a mind-body practice; it is important to recognize and counsel patients with messages appropriate to their stage of change and self-efficacy. Additionally, case studies that combine the voice of the clinician and the patient can provide useful illustrations of truly patient-centered care. PMID:24278842

  10. Exploring Personal Medicine as Part of Self-Directed Care: Expanding Perspectives on Medical Necessity.

    PubMed

    Snethen, Gretchen; Bilger, Andrea; Maula, Erme C; Salzer, Mark S

    2016-08-01

    Self-directed care (SDC) offers flexibility in and control over mental health services. This study examined the types of goods and services that individuals with serious mental illness request in an SDC intervention. Data were from a randomized controlled trial that enrolled adult participants receiving Medicaid-reimbursed services, with two years of expenditures at the 50%-90% level of all Medicaid enrollees in the county and no hospitalizations within six months of the study. Data were analyzed for 60 participants randomly assigned to an SDC intervention, who were allowed to make requests for and purchase nontraditional goods and services through a noncapitated fund. Requests were coded by using the section on activities and participation of the World Health Organization's International Classification of Function, Disability, and Health (ICF) model. Descriptive statistics are presented for the categories of requests made by participants. The 60 participants made a total of 507 requests, representing 621 ICF codes. Requests ranged from 0 to 37 requests per person, with a mean of 8.45 requests. The average time to first request was 95.5 days. Most codes were in the area of self-care (19%) and general tasks and demands (19%). Among the 52 participants who made requests, the mean was 11.94 requests, which addressed an average of 5.60 unique needs. Individuals with serious mental illness identified personal-medicine strategies to address needs that are currently unmet by traditional mental health services. Self-directed care may be a service delivery option that allows consumers to access their own personal medicine and better address their needs.

  11. Gender and factor-level interactions in psychopathy: implications for self-directed violence risk and borderline personality disorder symptoms.

    PubMed

    Verona, Edelyn; Sprague, Jenessa; Javdani, Shabnam

    2012-07-01

    Women with antisocial and psychopathic traits have a more extensive history of self-directed violence, as well as borderline personality disorder (BPD) symptoms, than their male counterparts (Chapman, Specht, & Cellucci, 2005; Warren et al., 2003). To inform this area of research, we examined gender differences in the relationship between psychopathy factors and risk for self-directed violence, as measured by a history of suicidal ideation, self-harm, and suicide attempts, across 2 studies. In both studies, we found that the interaction of the interpersonal-affective (Factor 1) and impulsive-antisocial traits (Factor 2) of psychopathy, a combination considered to exemplify high psychopathy, was associated with ideation, self-harm, and suicide attempt histories specifically in women. In men, Factor 2 traits were associated with these risk indices for self-directed violence, regardless of Factor 1. In Study 2, we extended our analysis to examine whether BPD accounted for the relationship between psychopathy and self-directed violence differentially in women and men. Results suggested that BPD symptoms partially accounted for the effects of Factor 2 on self-directed violence (both self-harm and attempts) in both genders but fully accounted for Factor 1 protective effects only in men. These findings underscore the notion that the same psychopathic trait liabilities, at least as they are currently assessed, may confer risk for different forms of behavioral maladjustment in women versus men. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  12. Spreading and spontaneous motility of multicellular aggregates on soft substrates

    NASA Astrophysics Data System (ADS)

    Brochard-Wyart, Françoise

    2013-03-01

    We first describe the biomechanics of multicellular aggregates, a model system for tissues and tumors. We first characterize the tissue mechanical properties (surface tension, elasticity, viscosity) by a new pipette aspiration technique. The aggregate exhibits a viscoelastic response but, unlike an inert fluid, we observe aggregate reinforcement with pressure, which for a narrow range of pressures results in pulsed contractions or shivering. We interpret this reinforcement as a mechanosensitive active response of the acto-myosin cortex. Such an active behavior has previously been found to cause tissue pulsation during dorsal closure of Drosophila embryo. We then describe the spreading of aggregates on rigid glass substrates, varying both intercellular and substrate adhesion. We find both partial and complete wetting regimes. For the dynamics, we find a universal spreading law at short time, analogous to that of a viscoelastic drop. At long time, we observe, for strong substrate adhesion, a precursor film spreading around the aggregate. Depending on aggregate cohesion, this precursor film can be a dense cellular monolayer (liquid state) or consist of individual cells escaping from the aggregate body (gas state). The transition from liquid to gas state appears also to be present in the progression of a tumor from noninvasive to metastatic, known as the epithelial-mesenchymal transition. Finally, we describe the effect of the substrate rigidity on the phase diagram of wetting. On soft gels decorated with fibronectin and strongly cohesive aggregates, we have observed a wetting transition induced by the substrate rigidity: on ultra soft gels, below an elastic modulus Ec the aggregates do not spread, whereas above Ec we observe a precursor film expending with a diffusive law. The diffusion coefficient D(E) present a maximum for E =Em. A maximum of mobility versus the substrate rigidity had also been observed for single cells. Near Em, we observe a new phenomenon: a cell

  13. Point of care information services: a platform for self-directed continuing medical education for front line decision makers

    PubMed Central

    Moja, Lorenzo; Kwag, Koren Hyogene

    2015-01-01

    The structure and aim of continuing medical education (CME) is shifting from the passive transmission of knowledge to a competency-based model focused on professional development. Self-directed learning is emerging as the foremost educational method for advancing competency-based CME. In a field marked by the constant expansion of knowledge, self-directed learning allows physicians to tailor their learning strategy to meet the information needs of practice. Point of care information services are innovative tools that provide health professionals with digested evidence at the front line to guide decision making. By mobilising self-directing learning to meet the information needs of clinicians at the bedside, point of care information services represent a promising platform for competency-based CME. Several points, however, must be considered to enhance the accessibility and development of these tools to improve competency-based CME and the quality of care. PMID:25655251

  14. Proliferation and motility of HaCaT keratinocyte derivatives is enhanced by fibroblast nemosis

    SciTech Connect

    Raesaenen, Kati; Vaheri, Antti

    2010-06-10

    The role of paracrine tumor-stroma regulation in the progression of cancer is under intense investigation. Activated fibroblasts are key components of the tumor microenvironment providing the soluble factors mediating the regulation. Nemosis is an experimental model to study these parameters: formation of a multicellular spheroid activates fibroblasts and leads to increased production of soluble factors involved in the promotion of growth and motility. Role of nemosis was investigated in the tumorigenesis of HaCaT derivatives representing skin carcinoma progression. Conditioned medium from fibroblast spheroids increased proliferation rate of HaCaT derivatives. Expression of proliferation marker Ki-67 increased significantly in benign A5 and low-grade malignant II-4 cells, but did not further increase in the metastatic RT3 cells. Expression of p63, keratinocyte stem cell marker linked to cancer progression, was augmented by medium from nemotic fibroblasts; this increase was also seen in RT3 cells. Scratch-wound healing of the keratinocytes was enhanced in response to fibroblast nemosis. Neutralizing antibodies against growth factors inhibited wound healing to some extent; the response varied between benign and malignant keratinocytes. Migration and invasion were enhanced by conditioned medium from nemotic fibroblasts in benign and low-grade malignant cells. RT3 keratinocyte migration was further augmented, but invasion was not, indicating their intrinsic capacity to invade. Our data demonstrate that fibroblast nemosis increases proliferation and motility of HaCaT keratinocyte derivatives, and thus nemosis can be used as a model to study the role of soluble factors secreted by fibroblasts in tumor progression.

  15. Self-Reported Usual Care for Self-Directed Violence during the Six Months Prior to Emergency Department Admission

    PubMed Central

    Comtois, Katherine Anne; Kerbrat, Amanda H.; Atkins, David C.; Roy-Byrne, Peter; Katon, Wayne J.

    2014-01-01

    Background The literature describing the health services individuals receive prior to and following self-directed violence is limited. Objectives This study examines services received for the six months preceding admission to an urban county medical center emergency department for self-directed violence. We predicted that individuals with at least one prior act of self-directed violence in the past six months would have received more services than those for whom the index admission was their only recent act. Method Participants were recruited from emergency department admissions during shifts selected to maximize representativeness. Participants (n=202) were interviewed using the Suicide Attempt Self-Injury Interview, Suicide Attempt Self-Injury Count, Treatment History Interview, MINI, Brief Symptom Index, and SF-12. Results The majority of index acts of self-directed violence (79%) were suicide attempts. The participants were characterized by low socio-economic status, substantial symptomatology, low physical and mental health functioning, and multiple psychiatric diagnoses. In the preceding six months, 34% were admitted to a hospital and 56% received crisis services (including 44% in the ED). While three quarters (76%) had seen an outpatient medical provider and most (70%) received psychotropic medications, less than half of the sample received psychiatric services (40%) or outpatient psychosocial treatment (48%). As predicted, utilization for most types of usual care was higher for those engaging in self-directed violence in the six months preceding the index admission. Conclusions Individuals admitted to this emergency department for self-directed violence received inadequate outpatient psychosocial and psychiatric services despite severe illness and disability. PMID:25494233

  16. The Learning Curve in Prostate MRI Interpretation: Self-Directed Learning Versus Continual Reader Feedback.

    PubMed

    Rosenkrantz, Andrew B; Ayoola, Abimbola; Hoffman, David; Khasgiwala, Anunita; Prabhu, Vinay; Smereka, Paul; Somberg, Molly; Taneja, Samir S

    2017-03-01

    The purpose of this study is to evaluate the roles of self-directed learning and continual feedback in the learning curve for tumor detection by novice readers of prostate MRI. A total of 124 prostate MRI examinations classified as positive (n = 52; single Prostate Imaging Reporting and Data System [PI-RADS] category 3 or higher lesion showing Gleason score ≥ 7 tumor at MRI-targeted biopsy) or negative (n = 72; PI-RADS category 2 or lower and negative biopsy) for detectable tumor were included. These were divided into four equal-sized batches, each with matching numbers of positive and negative examinations. Six second-year radiology residents reviewed examinations to localize tumors. Three of the six readers received feedback after each examination showing the preceding case's solution. The learning curve, plotting accuracy over time, was assessed by the Akaike information criterion (AIC). Logistic regression and mixed-model ANOVA were performed. For readers with and without feedback, the learning curve exhibited an initial rapid improvement that slowed after 40 examinations (change in AIC > 0.2%). Accuracy improved from 58.1% (batch 1) to 71.0-75.3% (batches 2-4) without feedback and from 58.1% to 72.0-77.4% with feedback (p = 0.027-0.046), without a difference in the extent of improvement (p = 0.800). Specificity improved from 53.7% to 68.5-81.5% without feedback and from 55.6% to 74.1-81.5% with feedback (p = 0.006-0.010), without a difference in the extent of improvement (p = 0.891). Sensitivity improved from 59.0-61.5% (batches 1-2) to 71.8-76.9% (batches 3-4) with feedback (p = 0.052), though did not improve without feedback (p = 0.602). Sensitivity for transition zone tumors exhibited larger changes (p = 0.024) with feedback than without feedback. Sensitivity for peripheral zone tumors did not improve in either group (p > 0.3). Reader confidence increased only with feedback (p < 0.001). The learning curve in prostate tumor detection largely reflected self-directed

  17. Pediatric resident and faculty attitudes toward self-assessment and self-directed learning: a cross-sectional study.

    PubMed

    Li, Su-Ting T; Favreau, Michele A; West, Daniel C

    2009-04-13

    The development of self-assessment and self-directed learning skills is essential to lifelong learning and becoming an effective physician. Pediatric residents in the United States are now required to use Individualized Learning Plans (ILPs) to document self-assessment and self-directed learning. A better understanding of resident and faculty attitudes and skills about self-assessment and self-directed learning will allow more successful integration of lifelong learning into residency education. The objective of this study was to compare faculty and resident attitudes, knowledge and skills about self-assessment, self-directed learning and ILPs. Survey of pediatric residents and faculty at a single institution. Respondents rated their attitudes, knowledge, and self-perceived skills surrounding self-assessment, self-directed learning and ILPs. Overall survey response rate was 81% (79/97); 100% (36/36) residents and 70% (43/61) faculty. Residents and faculty agreed that lifelong learning is a necessary part of being a physician. Both groups were comfortable with assessing their own strengths and weaknesses and developing specific goals to improve their own performance. However, residents were less likely than faculty to continuously assess their own performance (44% vs. 81%; p < 0.001) or continuously direct their own learning (53% vs. 86%; p < 0.001). Residents were more likely than faculty to believe that residents should be primarily responsible for directing their own learning (64% vs. 19%; p < 0.0001), but at the same time, more residents believed that assigned clinical (31% vs. 0%; p < 0.0001) or curricular (31% vs. 0%; p < 0.0001) experiences were sufficient to make them competent physicians. Interns were less likely than senior residents to have a good understanding of how to assess their own skills (8% vs. 58%; p = 0.004) or what it means to be a self-directed learner (50% vs. 83%; p = 0.04).Qualitative comments indicated that while ILPs have the potential to

  18. A general allometric and life-history model for cellular differentiation in the transition to multicellularity.

    PubMed

    Solari, Cristian A; Kessler, John O; Goldstein, Raymond E

    2013-03-01

    The transition from unicellular, to colonial, to larger multicellular organisms has benefits, costs, and requirements. Here we present a model inspired by the volvocine green algae that explains the dynamics involved in the unicellular-multicellular transition using life-history theory and allometry. We model the two fitness components (fecundity and viability) and compare the fitness of hypothetical colonies of different sizes with varying degrees of cellular differentiation to understand the general principles that underlie the evolution of multicellularity. We argue that germ-soma separation may have evolved to counteract the increasing costs and requirements of larger multicellular colonies. The model shows that the cost of investing in soma decreases with size. For lineages such as the Volvocales, as reproduction costs increase with size for undifferentiated colonies, soma specialization benefits the colony indirectly by decreasing such costs and directly by helping reproductive cells acquire resources for their metabolic needs. Germ specialization is favored once soma evolves and takes care of vegetative functions. To illustrate the model, we use some allometric relationships measured in Volvocales. Our analysis shows that the cost of reproducing an increasingly larger group has likely played an important role in the transition to multicellularity and cellular differentiation.

  19. A method of self-directed learning in continuing medical education with implications for recertification.

    PubMed

    Manning, P R; Clintworth, W A; Sinopoli, L M; Taylor, J P; Krochalk, P C; Gilman, N J; Denson, T A; Stufflebeam, D L; Knowles, M S

    1987-12-01

    A method of self-directed learning for physicians that can be used to satisfy a portion of specialty board recertification requirements integrates contract learning (self-formulated learning plans), information brokering (linking physicians with consultants and community resources), and collegial networking (discussion groups). The method encourages physicians to focus on educational objectives, supplies learning resources, and promotes interactions with colleagues in study groups. Fifty-nine (53%) of the 102 learning goals update physicians' knowledge. Print sources and discussions with experts were the commonest resources used. Forty-five (49%) of 91 participants completed their learning plans. Forty-nine (74%) completed projects were judged successful in achieving their goals. Twenty-five (45%) of 56 physicians responding to a questionnaire stated that the method was superior to traditional continuing medical education. Fifty-two percent of the participants found the method as effective as traditional continuing medical education. Proof of accomplishment allows the method to be used as part of a specialty board recertification process.

  20. Self directed home based electrical muscle stimulation training improves exercise tolerance and strength in healthy elderly.

    PubMed

    Caulfield, Brian; Prendergast, Ann; Rainsford, Gary; Minogue, Conor

    2013-01-01

    Advancing age is associated with a gradual decline in muscle strength, exercise tolerance and subsequent capacity for activities of daily living. It is important that we develop effective strategies to halt this process of gradual decline in order to enhance functional ability and capacity for independent living. To achieve this, we must overcome the challenge of sustaining ongoing engagement in physical exercise programmes in the sedentary elderly population, particularly those who experience barriers to exercise participation. Recent developments in electrical muscle stimulation technology could provide a potential solution. In this pilot case-control study we investigated the effects of a self-directed home based programme of electrical muscle stimulation training on muscle strength and exercise tolerance in a group of 16 healthy elderly volunteers (10f, 6m). Study participants completed 30 separate 1-hour electrical muscle stimulation sessions at home over a 6-week period. We observed significant improvements in quadriceps muscle strength and 6-minute walk distance, suggesting that this form of electrical muscle stimulation training has promise as an exercise modality in the elderly population.

  1. Promoting self-directed learning through portfolios in undergraduate medical education: the mentors' perspective.

    PubMed

    van Schaik, Sandrijn; Plant, Jennifer; O'Sullivan, Patricia

    2013-01-01

    Medical students need to acquire self-directed learning (SDL) skills for effective lifelong learning. Portfolios allow learners to reflect on their progress, diagnose learning needs and create learning plans, all elements of SDL. While mentorship is deemed to be essential for successful portfolio use, it is not known what constitutes effective mentorship in this process. In-depth understanding of the SDL construct seems a prerequisite. The aim of this study was to examine how portfolio mentors perceive and approach SDL. Interviews with faculty members who mentored medical students in portfolio were audio-recorded, transcribed and analysed for themes. Eight mentors participated. Qualitative analysis revealed six major themes around mentors' definitions of SDL, their perception of innate SDL abilities of medical students, their own approach to SDL, their understanding of the value of learning plans, their perceptions of students' engagement with the portfolio and the impact of the portfolio process on the mentoring relationship. This study revealed tensions between mentors' beliefs regarding the importance of SDL, their own approach to SDL and their perceptions of students' SDL skills. Based on our analysis of these tensions, we recommend both explicit faculty development and institutional culture change for successful integration of SDL in medical education.

  2. Role of Self-Directed Learning in Communication Competence and Self-Efficacy.

    PubMed

    Song, Youngshin; Yun, Soon Young; Kim, Sun-Ae; Ahn, Eun-Kyong; Jung, Mi Sook

    2015-10-01

    Although effective self-directed learning (SDL) has been shown to improve clinical performance, little is known about its role between communication competence and communication self-efficacy in nursing students. This study aimed to identify whether SDL mediates the relationship between communication competence and communication self-efficacy. A cross-sectional survey was conducted with a sample of 213 nursing students taking a basic fundamentals of nursing course. A path diagram, using structural equation modeling, was used to estimate the direct and indirect effects of communication competence on communication self-efficacy, controlling for SDL as a mediator. A structural equation model confirmed direct and indirect effects of communication competence on communication self-efficacy when SDL was controlled as a mediator. An appropriate fit to the data was identified in this mediation model of SDL. For enhancing self-efficacy regarding communication skill, the specified SDL program based on the level of communication competence will yield more effective results. Copyright 2015, SLACK Incorporated.

  3. Self-directed Learning in Otolaryngology Residents' Preparation for Surgical Cases.

    PubMed

    Jabbour, Jad; Bakeman, Anna; Robey, Thomas; Jabbour, Noel

    2017-04-01

    To characterize the nature of surgical preparation among otolaryngology residents nationwide, determine the self-rated effectiveness and efficiency of case preparation practices, and identify potential means for educational improvement. A survey examining the study objectives was developed and distributed to otolaryngology residents nationwide. Survey response data were submitted to descriptive analysis and comparative analyses between junior and senior residents. Literature regarding case preparation among otolaryngology residents was reviewed. Among 108 resident respondents, the most commonly used resources included textbooks (86.1%), surgical education websites (74.1%), and surgical atlases (66.7%). Time was the primary limitation (cited by 84.3%) and convenience the predominant factor influencing resource selection (92.5%). On a 5-point Likert scale, mean scores regarding effectiveness and efficiency of case preparation were 3.53 ± 0.68 and 3.19 ± 0.88, respectively. Senior residents compared to junior residents were more likely to rate their preparation as effective (3.75 ± 0.54 vs 3.40 ± 0.72, P = .008) and efficient (3.45 ± 0.85 vs 3.03 ± 0.86, P = .02). Otolaryngology residents do not consistently rate their case preparation as effective or efficient. While there appears to be progress in self-directed learning throughout residency, room for improvement remains, with potential avenues for such improvement explored here.

  4. Struggling to be self-directed: residents' paradoxical beliefs about learning.

    PubMed

    Nothnagle, Melissa; Anandarajah, Gowri; Goldman, Roberta E; Reis, Shmuel

    2011-12-01

    Self-directed learning (SDL) skills serve as the basis for physician lifelong learning; however, residency training does not typically emphasize SDL skills. To understand residents' needs regarding SDL curricula, the authors used qualitative methods to examine the residency learning culture and residents' views of SDL. The authors conducted individual, in-depth, semistructured interviews with all 13 final-year residents at the Brown University Family Medicine Residency Program. Interviews were audio taped and transcribed verbatim. Using an iterative individual and group process, four researchers conducted a qualitative analysis of the transcripts, identifying major themes and higher-order interpretations. Major themes included resident beliefs about learning, the learning culture in residency, and developmental progress in learning. Four paradoxes emerged in the analysis: (1) Residents understand and value the concept of SDL, but they engage in limited goal setting and reflection and report lack of skills to manage their own learning, particularly in the clinical setting. (2) Despite being immersed in what aims to be a learner-centered culture, many residents still value traditional, teacher-centered approaches. (3) Residents recognize patient care as the most powerful stimulus for SDL, but they often perceive patient care and learning as competing priorities. (4) Residents desire external guidance for SDL. Graduating residents lacked confidence in their SDL skills and their ability to manage their learning, especially in clinical settings. Fostering SDL skills during residency will likely require training and guidance for SDL as well as changes in the structure and culture of residency.

  5. The relative influence of different domains of social connectedness on self-directed violence in adolescence.

    PubMed

    Kaminski, Jennifer W; Puddy, Richard W; Hall, Diane M; Cashman, Sandra Y; Crosby, Alexander E; Ortega, Lavonne A G

    2010-05-01

    Previous research has linked greater social connectedness with a lowered risk of self-directed violence among adolescents. However, few studies have analyzed the comparative strength of different domains of connectedness (e.g., family, peers and school) to determine where limited resources might best be focused. Data to address that gap were taken from the Centers for Disease Control and Prevention's Student Health and Safety Survey, administered to 4,131 7th-12th graders (51.5% female; 43.8% Hispanic; 22.6% African American or Black). Logistic regressions (controlling for age, gender, race/ethnicity, family structure, academic performance, and depressive symptoms) suggest that family connectedness was a stronger predictor than connectedness to peers, school, or adults at school for non-suicidal self-harm, suicidal ideation, suicide plans, and non-fatal suicidal behavior. In some analyses, peer connectedness was unexpectedly a risk factor. Results have implications for prevention of suicide in adolescence, especially in the context of the current trend towards school-based prevention programs.

  6. Development and characterisation of a 3D multi-cellular in vitro model of normal human breast: a tool for cancer initiation studies.

    PubMed

    Nash, Claire E; Mavria, Georgia; Baxter, Euan W; Holliday, Deborah L; Tomlinson, Darren C; Treanor, Darren; Novitskaya, Vera; Berditchevski, Fedor; Hanby, Andrew M; Speirs, Valerie

    2015-05-30

    Multicellular 3-dimensional (3D) in vitro models of normal human breast tissue to study cancer initiation are required. We present a model incorporating three of the major functional cell types of breast, detail the phenotype and document our breast cancer initiation studies. Myoepithelial cells and fibroblasts were isolated and immortalised from breast reduction mammoplasty samples. Tri-cultures containing non-tumorigenic luminal epithelial cells HB2, or HB2 overexpressing different HER proteins, together with myoepithelial cells and fibroblasts were established in collagen I. Phenotype was assessed morphologically and immunohistochemically and compared to normal breast tissue. When all three cell types were present, polarised epithelial structures with lumens and basement membrane production were observed, akin to normal human breast tissue. Overexpression of HER2 or HER2/3 caused a significant increase in size, while HER2 overexpression resulted in development of a DCIS-like phenotype. In summary, we have developed a 3D tri-cellular model of normal human breast, amenable to comparative analysis after genetic manipulation and with potential to dissect the mechanisms behind the early stages of breast cancer initiation.

  7. Handbook Preparation as a Tool for Self-Directed Learning Process: A Case Study on Endocrine Topic

    ERIC Educational Resources Information Center

    Cerrah Ozsevgec, Lale; Ayas, Alipasa; Ozsevgec, Tuncay

    2010-01-01

    This study examines the effectiveness of handbook preparation as a method in the self-directed learning process of student teachers in teaching endocrine glands, and increasing their levels of knowledge. Thirty student teachers were selected from a biology department. A pencil and paper test and a clinical interview procedure were used to collect…

  8. Enhancing Learners' Self-Directed Use of Technology for Language Learning: The Effectiveness of an Online Training Platform

    ERIC Educational Resources Information Center

    Lai, Chun; Shum, Mark; Tian, Yan

    2016-01-01

    Enhancing self-directed use of technology for language learning is essential for maximizing the potential of technology for language learning. Understanding how to construct learner training to promote this critical competency is of great significance. This study examined the effectiveness of an online training platform aimed at enhancing the…

  9. Gender as a Context for Interpreting the Self-Directed Learning Experiences of Prostate and Breast Cancer Patients

    ERIC Educational Resources Information Center

    Rager, Kathleen B.

    2007-01-01

    This article reports the findings from a secondary analysis of the data from two qualitative studies conducted by the researcher regarding the self-directed learning experiences of prostate and breast cancer patients. Of interest were possible differences in the descriptions of the participants' experiences that appear to relate to gender.…

  10. The Effects of Portfolio-Based Advice on the Development of Self-Directed Learning Skills in Secondary Vocational Education

    ERIC Educational Resources Information Center

    Kicken, Wendy; Brand-Gruwel, Saskia; van Merrienboer, Jeroen J. G.; Slot, Wim

    2009-01-01

    This experimental study was designed to investigate whether supervision meetings, in which students receive specific advice on how to use a development portfolio to monitor their progress and plan their future learning, helps them to develop self-directed learning skills and improve their learning in the domain. In the first year of a hairdressing…

  11. Understanding Self-Directed Learning in the Context of Mobile Web 2.0--Case Study with Workplace Learners

    ERIC Educational Resources Information Center

    Gu, Jia

    2016-01-01

    This paper presents the findings from a multiple-case study which has investigated the impact of mobile Web 2.0 technologies on self-directed learning (SDL) of workplace learners by exploring participants' learning experiences with a mobile App. Drawing on existing literatures, we examined learners' SDL personal attributes and process in the…

  12. Improving temporal bone dissection using self-directed virtual reality simulation: results of a randomized blinded control trial.

    PubMed

    Zhao, Yi Chen; Kennedy, Gregor; Yukawa, Kumiko; Pyman, Brian; O'Leary, Stephen

    2011-03-01

    A significant benefit of virtual reality (VR) simulation is the ability to provide self-direct learning for trainees. This study aims to determine whether there are any differences in performance of cadaver temporal bone dissections between novices who received traditional teaching methods and those who received unsupervised self-directed learning in a VR temporal bone simulator. Randomized blinded control trial. Royal Victorian Eye and Ear Hospital. Twenty novice trainees. After receiving an hour lecture, participants were randomized into 2 groups to receive an additional 2 hours of training via traditional teaching methods or self-directed learning using a VR simulator with automated guidance. The simulation environment presented participants with structured training tasks, which were accompanied by real-time computer-generated feedback as well as real operative videos and photos. After the training, trainees were asked to perform a cortical mastoidectomy on a cadaveric temporal bone. The dissection was videotaped and assessed by 3 otologists blinded to participants' teaching group. The overall performance scores of the simulator-based training group were significantly higher than those of the traditional training group (67% vs 29%; P < .001), with an intraclass correlation coefficient of 0.93, indicating excellent interrater reliability. Using other assessments of performance, such as injury size, the VR simulator-based training group also performed better than the traditional group. This study indicates that self-directed learning on VR simulators can be used to improve performance on cadaver dissection in novice trainees compared with traditional teaching methods alone.

  13. Designing On-Demand Education for Simultaneous Development of Domain-Specific and Self-Directed Learning Skills

    ERIC Educational Resources Information Center

    Taminiau, E. M. C.; Kester, L.; Corbalan, G.; Spector, J. M.; Kirschner, P. A.; Van Merriënboer, J. J. G.

    2015-01-01

    On-demand education enables individual learners to choose their learning pathways according to their own learning needs. They must use self-directed learning (SDL) skills involving self-assessment and task selection to determine appropriate pathways for learning. Learners who lack these skills must develop them because SDL skills are prerequisite…

  14. Understanding the Self-Directed Online Learning Preferences, Goals, Achievements, and Challenges of MIT OpenCourseWare Subscribers

    ERIC Educational Resources Information Center

    Bonk, Curtis J.; Lee, Mimi Miyoung; Kou, Xiaojing; Xu, Shuya; Sheu, Feng-Ru

    2015-01-01

    This research targeted the learning preferences, goals and motivations, achievements, challenges, and possibilities for life change of self-directed online learners who subscribed to the monthly OpenCourseWare (OCW) e-newsletter from MIT. Data collection included a 25-item survey of 1,429 newsletter subscribers; 613 of whom also completed an…

  15. #TwitterforTeachers: The Implications of Twitter as a Self-Directed Professional Development Tool for K-12 Teachers

    ERIC Educational Resources Information Center

    Visser, Ryan D.; Evering, Lea Calvert; Barrett, David E.

    2014-01-01

    This mixed-methods study explores how K-12 teachers use Twitter. An online survey was disseminated via Twitter to gauge their usage of, access to, and perceptions of Twitter. The results indicated that teachers highly value Twitter as a means of self-directed professional development. Respondents who reported using Twitter multiple times a day…

  16. Paid Educational Leave and Self-Directed Learning: Implications for Legislation on the Learning Leave Scheme in South Korea

    ERIC Educational Resources Information Center

    Oh, Jeong Rok; Park, Cho Hyun; Jo, Sung Jun

    2016-01-01

    Purpose: The purposes of this study are to explore paid educational leave (PEL), self-directed learning (SDL) and the relationship between them; and to identify the implications for legislation on the learning leave scheme in South Korea. Design/Methodology/Approach: The research method of the study is a literature review. Articles were identified…

  17. Self-Perceived and Observable Self-Direction in an Online Asynchronous Programming Course Using Peer Learning Forums

    ERIC Educational Resources Information Center

    Gaspar, Alessio; Langevin, Sarah; Boyer, Naomi; Armitage, William

    2009-01-01

    This study broadens the objectives of previous work (Boyer, N., Langevin, S., Gaspar, A. (2008). "Self direction and constructivism in programming education." "Proceedings of the ACM Special Interest Group in IT Education Conference," 16-18 October 2008, Cincinnati, OH) in which we used a survey-based instrument, the Personal…

  18. Paraprofessionals' Perceptions on Delivering Infant Feeding Lessons to Disadvantaged Mothers via a Self-Directed Computer-Supported Method

    ERIC Educational Resources Information Center

    Singleterry, Lisa R.; Horodynski, Mildred A.

    2012-01-01

    Objective: To ascertain paraprofessionals' perceptions regarding a self-directed computer-supported nutrition educational intervention to disadvantaged mothers of infants. Design: Qualitative focus group study. Setting: Three county extension programs in a Midwestern state, which serve disadvantaged families. Method: Sixteen paraprofessional…

  19. Developing a "Self-Directed Learning Preparation Skills Scale for Primary School Students": Validity and Reliability Analyses

    ERIC Educational Resources Information Center

    Gündüz, Gülten Feryal; Selvi, Kiymet

    2016-01-01

    The purpose of this study is to develop "Self-Directed Learning Preparation Skills Scale" for primary school students. Data were gathered according to the principles of descriptive research method. In order to develop this scale, draft items were developed through review of literature, interviews done with teachers, parents and students…

  20. Interest Profile Elevation, Big Five Personality Traits, and Secondary Constructs on the Self-Directed Search: A Replication and Extension

    ERIC Educational Resources Information Center

    Bullock, Emily E.; Reardon, Robert C.

    2008-01-01

    The study used the Self-Directed Search (SDS) and the NEO-FFI to explore profile elevation, four secondary constructs, and the Big Five personality factors in a sample of college students in a career course. Regression model results showed that openness, conscientiousness, differentiation high-low, differentiation Iachan, and consistency accounted…