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2015

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English Education In Thailand And Singapore : Differences In English Education, Use And Identity, Chelsey Hice Jan 2015

English Education In Thailand And Singapore : Differences In English Education, Use And Identity, Chelsey Hice

University Honors Theses

The Secretary General of ASEAN asserted the importance of education and the use English in promoting and bringing prosperity to the ASEAN nations. "Through education, through the use of English language and, more importantly, with a heightened sense of ASEAN Identity and ASEAN Community, we hope that ASEAN integration and cooperation will bring both benefits and opportunities to the region" (Le Luong Minh, 2013). Taking Thailand and Singapore into consideration, it is clear that national realities vary greatly within the region in regards to English proficiency rates. Education First’s 2013 English Proficiency Index Report revealed that Singapore was the second …


Heteroskedasticity Of Unknown Form In Spatial Autoregressive Models With A Moving Average Disturbance Term, Osman Dogan Jan 2015

Heteroskedasticity Of Unknown Form In Spatial Autoregressive Models With A Moving Average Disturbance Term, Osman Dogan

Publications and Research

In this study, I investigate the necessary condition for the consistency of the maximum likelihood estimator (MLE) of spatial models with a spatial moving average process in the disturbance term. I show that the MLE of spatial autoregressive and spatial moving average parameters is generally inconsistent when heteroskedasticity is not considered in the estimation. I also show that the MLE of parameters of exogenous variables is inconsistent and determine its asymptotic bias. I provide simulation results to evaluate the performance of the MLE. The simulation results indicate that the MLE imposes a substantial amount of bias on both autoregressive and …


Survey Of California Pharmacists' Awareness Of And Readiness For The New Authorities Granted By Sb 493: A Pilot Study, Clipper Young, Kajua B. Lor, Gordon C. Mccarter, Robert J. Ignoffo Jan 2015

Survey Of California Pharmacists' Awareness Of And Readiness For The New Authorities Granted By Sb 493: A Pilot Study, Clipper Young, Kajua B. Lor, Gordon C. Mccarter, Robert J. Ignoffo

Faculty Publications & Research of the TUC College of Pharmacy

The recent passing of Senate Bill (SB) 493 – effective on January 1, 2014 – addresses a primary care provider shortage in California by declaring pharmacists as health care providers and authorizing new roles for them in patient care. The aims of this pilot study were to examine California registered pharmacists’ awareness and knowledge of the expanded authorities granted by SB 493 as well as to assess their perception of their own readiness to exercise these new authorities. A cross-sectional, observational study was designed, and a 40-question survey was administered electronically through Qualtrics to adjunct faculty, clinical faculty, and alumni …


Solid Microneedles For Transdermal Delivery Of Amantadine Hydrochloride And Pramipexole Dihydrochloride, Mylien T. Hoang, Kevin B. Ita, Daniel A. Bair Jan 2015

Solid Microneedles For Transdermal Delivery Of Amantadine Hydrochloride And Pramipexole Dihydrochloride, Mylien T. Hoang, Kevin B. Ita, Daniel A. Bair

Faculty Publications & Research of the TUC College of Pharmacy

The aim of this project was to study the influence of microneedles on transdermal delivery of amantadine hydrochloride and pramipexole dihydrochloride across porcine ear skin in vitro. Microchannel visualization studies were carried out and characterization of the microchannel depth was performed using confocal laser scanning microscopy (CLSM) to demonstrate microchannel formation following microneedle roller application. We also report, for the first time, the use of TA.XT Plus Texture Analyzer to characterize burst force in pig skin for transdermal drug delivery experiments. This is the force required to rupture pig skin. The mean passive flux of amantadine hydrochloride, determined using a …


Quantitative Spatial Frequency Fluorescence Imaging In The Sub-Diffusive Domain For Image-Guided Glioma Resection, Mira Sibai, Israel Veilleux, Jonathan T. Elliott, Frederic Leblond, Brian Wilson Jan 2015

Quantitative Spatial Frequency Fluorescence Imaging In The Sub-Diffusive Domain For Image-Guided Glioma Resection, Mira Sibai, Israel Veilleux, Jonathan T. Elliott, Frederic Leblond, Brian Wilson

Dartmouth Scholarship

Intraoperative 5- aminolevulinic acid induced-Protoporphyrin IX (PpIX) fluorescence guidance enables maximum safe resection of glioblastomas by providing surgeons with real-time tumor optical contrast. However, visual assessment of PpIX fluorescence is subjective and limited by the distorting effects of light attenuation and tissue autofluorescence. We have previously shown that non-invasive point measurements of absolute PpIX concentration identifies residual tumor that is otherwise non-detectable. Here, we extend this approach to wide-field quantitative fluorescence imaging by implementing spatial frequency domain imaging to recover tissue optical properties across the field-of-view in phantoms and ex vivo tissue.


Robust Fast Direct Integral Equation Solver For Quasi-Periodic Scattering Problems With A Large Number Of Layers, Min Hyung Cho, Alex H. Barnett Jan 2015

Robust Fast Direct Integral Equation Solver For Quasi-Periodic Scattering Problems With A Large Number Of Layers, Min Hyung Cho, Alex H. Barnett

Dartmouth Scholarship

We present a new boundary integral formulation for time-harmonic wave diffraction from two-dimensional structures with many layers of arbitrary periodic shape, such as multilayer dielectric gratings in TM polarization. Our scheme is robust at all scattering parameters, unlike the conventional quasi-periodic Green’s function method which fails whenever any of the layers approaches a Wood anomaly. We achieve this by a decomposition into near- and far-field contributions. The former uses the free-space Green’s function in a second-kind integral equation on one period of the material interfaces and their immediate left and right neighbors; the latter uses proxy point sources and small …


A Basic Guide For Empirical Environmental Social Science, Michael Cox Jan 2015

A Basic Guide For Empirical Environmental Social Science, Michael Cox

Dartmouth Scholarship

In this paper, I address a gap in the literature on environmental social science by providing a basic rubric for the conduct of empirical research in this interdisciplinary field. Current literature displays a healthy diversity of methods and techniques, but this has also been accompanied by a lack of consistency in the way in which research in this area is done. In part this can be seen as resulting from a lack in supporting texts that would provide a basis for this consistency. Although relevant methods texts do exist, these are not written with this type of research explicitly in …


Robust And Efficient Solution Of The Drum Problem Via Nyström Approximation Of The Fredholm Determinant, Lin Zhao, Alex Barnett Jan 2015

Robust And Efficient Solution Of The Drum Problem Via Nyström Approximation Of The Fredholm Determinant, Lin Zhao, Alex Barnett

Dartmouth Scholarship

The “drum problem''---finding the eigenvalues and eigenfunctions of the Laplacian with Dirichlet boundary condition---has many applications, yet remains challenging for general domains when high accuracy or high frequency is needed. Boundary integral equations are appealing for large-scale problems, yet certain difficulties have limited their use. We introduce the following two ideas to remedy this: (1) We solve the resulting nonlinear eigenvalue problem using Boyd's method for analytic root-finding applied to the Fredholm determinant, and we show that this is many times faster than the usual iterative minimization of a singular value. (2) We fix the problem of spurious exterior resonances …


Acute Kidney Injury Risk Prediction In Patients Undergoing Coronary Angiography In A National Veterans Health Administration Cohort With External Validation, Jeremiah R. Brown, Todd A. Mackenzie, Thomas M. Maddox, James Fly, Thomas T. Tsai, Mary E. Plomondon, Christopher D. Nielson, Edward D. Siew, Frederic S. Resnic, Clifton R. Baker, John S. Rumsfeld, Michael E. Matheny Jan 2015

Acute Kidney Injury Risk Prediction In Patients Undergoing Coronary Angiography In A National Veterans Health Administration Cohort With External Validation, Jeremiah R. Brown, Todd A. Mackenzie, Thomas M. Maddox, James Fly, Thomas T. Tsai, Mary E. Plomondon, Christopher D. Nielson, Edward D. Siew, Frederic S. Resnic, Clifton R. Baker, John S. Rumsfeld, Michael E. Matheny

Dartmouth Scholarship

Background:

Acute kidney injury (AKI) occurs frequently after cardiac catheterization and percutaneous coronary intervention. Although a clinical risk model exists for percutaneous coronary intervention, no models exist for both procedures, nor do existing models account for risk factors prior to the index admission. We aimed to develop such a model for use in prospective automated surveillance programs in the Veterans Health Administration.

Methods and Results:

We collected data on all patients undergoing cardiac catheterization or percutaneous coronary intervention in the Veterans Health Administration from January 01, 2009 to September 30, 2013, excluding patients with chronic dialysis, end‐stage renal disease, renal …


Methods And Data For Developing Coordinated Population Forecasts, Portland State University. Population Research Center Jan 2015

Methods And Data For Developing Coordinated Population Forecasts, Portland State University. Population Research Center

Publications, Reports and Presentations

This document is to accompany the coordinated population forecasts and their corresponding reports prepared by the Population Research Center (PRC).

Developing long-term coordinated population forecasts for a county and its sub-areas (UGBs and areas outside UGBs are referred to sub-areas in this document), requires these main stages: 1) compiling and evaluating historical and recent data to ascertain demographic characteristics and trends in the study area and to obtain a population base from which the forecasts may be launched; 2) making assumptions about the future and adjusting the data or rates in the forecasting models (calibrating the models) to incorporate predicted …


Idaho Teacher’S Attitudes About Child Abuse And/Or Neglect: Trends And Implications Of Reporting, Leah Meredith Huff Jan 2015

Idaho Teacher’S Attitudes About Child Abuse And/Or Neglect: Trends And Implications Of Reporting, Leah Meredith Huff

Northwest Journal of Teacher Education

This mixed-methods study investigated problems impeding teachers and, in particular, Idaho elementary teachers in fulfilling their responsibility to report child abuse and neglect (CAN) as mandated by law. Teachers were asked about their desires to know more about child protective services (CPS) and its court process. Quantitative data was gathered from a sample of 25 teachers using an adapted version of Teachers and Child Abuse Questionnaire (ECAQ). Qualitative data was obtained from teacher interviews. Both sets of data were analyzed separately and compared providing triangulation. Teachers reported uncertainty about education adequacy pertaining to CAN. Teachers wanted to know more about …


Arginine Supplementation Strategies During Gestation: Impacts On Dams And Offspring, Jena Lee Bjertness Jan 2015

Arginine Supplementation Strategies During Gestation: Impacts On Dams And Offspring, Jena Lee Bjertness

Animal Sciences

We hypothesize rumen-protected arginine supplementation during gestation will mitigate deleterious offspring effects caused by undernutrition. Experiment 1: non-pregnant ewes were supplemented with rumen-protected arginine at varying doses to assess effects on circulating amino acids and carotid hemodynamics. Arginine concentrations post-supplementation were greater in ewes supplemented with 180 vs. 90 mg/kg BW, and vascular resistance indices were lesser with 180 mg/kg BW; therefore, 180 mg/kg BW was used in experiment 2. Experiment 2: nutrient-restricted pregnant ewes were supplemented with rumen-protected arginine and maternal and offspring growth and physiological responses were measured. Arginine supplementation to nutrient restricted ewes improved offspring development compared …


The Jekyll And Hyde Of First Amendment Limits On The Regulation Of Judicial Campaign Speech, Gardner C. Geyh Jan 2015

The Jekyll And Hyde Of First Amendment Limits On The Regulation Of Judicial Campaign Speech, Gardner C. Geyh

Vanderbilt Law Review

No abstract provided.


Community-Based Participatory Research With Communities Defined By Race, Ethnicity, And Disability: Translating Theory To Practice, Christina Nicolaidis, Dora Raymaker Jan 2015

Community-Based Participatory Research With Communities Defined By Race, Ethnicity, And Disability: Translating Theory To Practice, Christina Nicolaidis, Dora Raymaker

School of Social Work Faculty Publications and Presentations

Community-based participatory research (CBPR) is an increasingly popular participatory research approach where community members and academics collaborate as equal partners to conduct research for improving health and wellbeing through action (Isreal et al., 2003; Wallerstein and Duran, 2003). It is a branch of action research in the tradition of emancipatory practice. CBPR grew within the health sciences in the 1990s in response to a number of issues with mainstream health science research and minority communities …


Connecting Curriculum To Community Research: Professional Services, Research, And Teaching, W. Barry Messer, Peter J. Collier Jan 2015

Connecting Curriculum To Community Research: Professional Services, Research, And Teaching, W. Barry Messer, Peter J. Collier

Urban Studies and Planning Faculty Publications and Presentations

Portland State University’s Community Environmental Services (CES) has helped shape the Portland metropolitan region’s sustainable materials management practices for more than twenty-five years. CES’s research and program development services have benefited community partners that in turn have provided hundreds of students with rich educational experiences. PSU faculty members also advance their pedagogical and research agendas through the development of CES-affiliated capstone courses. This article explores the CES co-production model from the perspectives of students, faculty members, and community partners.


Workshop Synthesis: Sampling Issues, Data Quality & Data Protection, Jimmy Armoogum, Jennifer Dill Jan 2015

Workshop Synthesis: Sampling Issues, Data Quality & Data Protection, Jimmy Armoogum, Jennifer Dill

Urban Studies and Planning Faculty Publications and Presentations

This workshop discussed various aspect of the mathematical part of survey methodology, as well as archiving and confidentiality issues aimed at improving data quality and its use through time. Participants identified ways to correct or minimize bias by dealing with incomplete sampling frames, using weighing and imputing procedures. We discussed methods to archive and share GPS-based survey data to preserve anonymity. Finally, we debated research needs on these topics for the next following years.


Retail Rent With Respect To Distance From Light Rail Transit Stations In Dallas And Denver, Arthur C. Nelson, Dejan Eskic, Joanna P. Ganning, Shima Hamidi, Susan J. Petheram, Jenny H. Liu, Reid Ewing Jan 2015

Retail Rent With Respect To Distance From Light Rail Transit Stations In Dallas And Denver, Arthur C. Nelson, Dejan Eskic, Joanna P. Ganning, Shima Hamidi, Susan J. Petheram, Jenny H. Liu, Reid Ewing

Urban Studies and Planning Faculty Publications and Presentations

A growing body of recent research is challenging the assumptions underlying the half-mile-circle in planning for development around transit stations. In this article we review this literature and extend it to include retail land uses. We estimate the rent premium conferred on retail properties in metropolitan Dallas and metropolitan Denver, both of which have extensive light rail transit systems. We find that consistent with half-mile-circle assumptions, retail rent premiums extend only to about 0.30 mile from transit stations with half the premium dissipating after a few hundred feet and three quarters within the first 0.10 mile. We offer implications for …


Comparing Two Common Approaches To Public Transit Service Equity Evaluation, Alex Karner, Aaron Golub Jan 2015

Comparing Two Common Approaches To Public Transit Service Equity Evaluation, Alex Karner, Aaron Golub

Urban Studies and Planning Faculty Publications and Presentations

Understanding the equity effects of transit service changes requires good information about the demographics of transit ridership. Both on-board survey data and census data can be used to estimate equity effects, though there is no clear reason these two sources will result in the same finding of impact. Guidance from the Federal Transit Administration (FTA) recommends using either of these data sources to estimate equity impacts. This article makes a direct comparison of the two methods for the public transit system in the Phoenix, Arizona metropolitan area. The results indicate that, although both sources are acceptable for FTA compliance, the …


Online Community-Based Learning As The Practice Of Freedom: The Online Capstone Experience At Portland State University, Deborah Smith Arthur, Zapoura Newton-Calvert Jan 2015

Online Community-Based Learning As The Practice Of Freedom: The Online Capstone Experience At Portland State University, Deborah Smith Arthur, Zapoura Newton-Calvert

University Studies Faculty Publications and Presentations

Given the design of Portland State University’s (PSU) undergraduate curriculum culminating in a capstone experience, the dramatic growth in online courses and online enrollments required a re-thinking of the capstone model to ensure all students could participate in this effective learning model and have a powerful learning experience. In recent years, a number of capstone courses have been developed that are offered fully online. This article examines PSU’s development of and institutional support for community-based learning (CBL) capstone courses in a fully online format. Emerging best practices and lessons learned may be useful for other institutions seeking to integrate experiential …


Sustaining Change: Successes, Challenges, And Lessons Learned From Twenty Years Of Empowering Students Through Community-Based Learning Capstones, Seanna M. Kerrigan Jan 2015

Sustaining Change: Successes, Challenges, And Lessons Learned From Twenty Years Of Empowering Students Through Community-Based Learning Capstones, Seanna M. Kerrigan

University Studies Faculty Publications and Presentations

More than four thousand students engage in the community-based learning capstone program every year by enrolling in one of 240 senior-level courses that culminate their undergraduate education. In this article, the author shares the context and history of the program, its foundational principles and processes, and the nuts-and-bolts details of the ongoing operation of the largest community-based learning capstone program in the United States.


Mind And Life: Is The Materialist Neo-Darwinian Conception Of Nature False?, Martin Zwick Jan 2015

Mind And Life: Is The Materialist Neo-Darwinian Conception Of Nature False?, Martin Zwick

Complex Systems Faculty Publications and Presentations

A partial review of Thomas Nagel's book, Mind and Cosmos: Why the Materialist NeoDarwinian Conception of Nature Is Almost Certainly False is used to articulate some systems-theoretic ideas about the challenge of understanding subjective experience. The article accepts Nagel' s view that reductionist materialism fails as an approach to this challenge, but argues that seeking an explanation of mind based on emergence is more plausible than one based on panpsychism, which Nagel favors. However, the article proposes something similar to Nagel's neutral monism by positing a hierarchy of information processes that span the domains of matter, life, and mind. As …


Gaining Policy Insight With A System Dynamics Model Of Pain Medicine Prescribing, Diversion And Abuse, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt Jan 2015

Gaining Policy Insight With A System Dynamics Model Of Pain Medicine Prescribing, Diversion And Abuse, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt

Complex Systems Faculty Publications and Presentations

Misuse of pain medicine is a leading cause of accidental deaths in the USA—over 15,000 deaths annually. A system dynamics model was developed and used to study the impact of three types of policy interventions to reduce adverse outcomes. Besides medical usage, the model also includes the diversion of pain medicines and their nonmedical use. Model behavior compared favourably with historical data at multiple points in the system. A prescription drug monitoring program intervention reduced nonmedical overdoses through supply restriction, and an intervention to reduce popularity of nonmedical usage reduced nonmedical overdoses by curtailing demand. A tamper-resistant drug formulation intervention …


Annual Faculty Senate Minutes October 2015 - June 2016, Portland State University Faculty Senate Jan 2015

Annual Faculty Senate Minutes October 2015 - June 2016, Portland State University Faculty Senate

Annual Compilations of the Faculty Senate Minutes (Minutes Only)

Minutes of the Faculty Senate for October 2015 to June 2016.


Integrating Information Literacy, The Pogil Method, And Ipads Into A Foundational Studies Program, Carrie Moore, Jennifer Black, Barbara C. Glackin, Margie Ruppel, Elaine Watson Jan 2015

Integrating Information Literacy, The Pogil Method, And Ipads Into A Foundational Studies Program, Carrie Moore, Jennifer Black, Barbara C. Glackin, Margie Ruppel, Elaine Watson

Library Faculty and Staff Publications and Presentations

This article provides an overview of the design, implementation, revision and informal assessment of an information literacy curriculum embedded in a new University Foundations (UF) program at a mid‐sized public university. The library information literacy sessions incorporated teambased learning and Process Oriented Guided Inquiry Learning (POGIL) elements using iPads. Each session provided students an opportunity to develop and apply information literacy skills, and included critical thinking questions which led students to think about underlying concepts. A focus group with the librarians assessed the UF library curriculum, its impact on student engagement, and the training activities for librarian teaching preparation.


Psychometric Evaluation Of Lexical Diversity Indices: Assessing Length Effects, Gerasimos Fergadiotis, Heather Harris Wright, Samuel B. Green Jan 2015

Psychometric Evaluation Of Lexical Diversity Indices: Assessing Length Effects, Gerasimos Fergadiotis, Heather Harris Wright, Samuel B. Green

Speech and Hearing Sciences Faculty Publications and Presentations

Purpose—Several novel techniques have been developed recently to assess the breadth of speaker’s vocabulary exhibited in a language sample. The specific aim of this study was to increase our understanding of the validity of the scores generated by different lexical diversity (LD) estimation techniques. Four techniques were explored: D, Maas, Measure of Textual Lexical Diversity (MTLD), and the Moving Average Type Token Ratio (MATTR).

Method—Four LD indices were estimated for language samples on four discourse tasks (procedures, eventcasts, story retell, and recounts) from 442 neurologically intact adults. The resulting data were analyzed using structural equation modeling.

Results—The scores on the …


The Aesthetic Pulse Of The Everyday: Defending Dewey, Kalle Puolakka Jan 2015

The Aesthetic Pulse Of The Everyday: Defending Dewey, Kalle Puolakka

Contemporary Aesthetics (Journal Archive)

In the relatively fragmented field of everyday aesthetics, some issues have gradually become the subject of increasingly heated debate. One of the primary disputes concerns aesthetic experience and how that concept should be understood. This article defends the view that the conception of aesthetic experience developed by John Dewey offers a much more promising foundation for a theory on the aesthetics of everyday life than some scholars have believed.


The Cacaio Project: Education For Environmental, Aesthetic And Moral Development, Atila T. Calvente Jan 2015

The Cacaio Project: Education For Environmental, Aesthetic And Moral Development, Atila T. Calvente

Contemporary Aesthetics (Journal Archive)

Economic inequalities, institutional awkwardness, cultural underdevelopment, social exclusion, a fast rate of environmental, ecological, and biodiversity degradation have all been at the root of historic social injustice and structural poverty in Brazil for centuries. Human development and emancipation in this context should be approached as a set of non-formal educational practices to promote better learning and dignity. These would become potent means for reducing material poverty and selfish individual behavior, and for improving holistic modes of education and culture. Non-traditional educational practices can have an important influence in state-run schools, as well as in private schools, by enhancing resilience and …


Performing Politics, Troy R.E. Paddock Jan 2015

Performing Politics, Troy R.E. Paddock

Contemporary Aesthetics (Journal Archive)

Walter Benjamin’s observation that fascism turns politics into aesthetics is, by now, a well-worn idea. This article argues that Benjamin’s critique of politics can apply just as much to the modern democratic politics of the United States. Borrowing from Benjamin, Jürgen Habermas, and Carl Schmitt, this article suggests that modern political discourse in the United States does not follow the classical liberal ideal of rational discourse in the marketplace of ideas within the public sphere. Instead, contemporary politics has become spectacle where images and slogans replace thought and debate in a 24/7 news cycle and political infotainment programs. The result …


Incomplete Adherence Among Treatment-Experienced Adults On Antiretroviral Therapy In Tanzania, Uganda And Zambia, Julie A. Denison, Olivier Koole, Sharon Tsui, Joris Menten, Kwasi Torpey, Eric Van Praag, Ya Diul Mukadi, Robert Colebunders, Andrew F. Auld, Simon G. Agolory, Jonathan Kaplan, Modest Mulenga, Gideon Kwesigabo, Fred Wabwire-Mangen, David Bangsberg Jan 2015

Incomplete Adherence Among Treatment-Experienced Adults On Antiretroviral Therapy In Tanzania, Uganda And Zambia, Julie A. Denison, Olivier Koole, Sharon Tsui, Joris Menten, Kwasi Torpey, Eric Van Praag, Ya Diul Mukadi, Robert Colebunders, Andrew F. Auld, Simon G. Agolory, Jonathan Kaplan, Modest Mulenga, Gideon Kwesigabo, Fred Wabwire-Mangen, David Bangsberg

OHSU-PSU School of Public Health Faculty Publications and Presentations

Objectives—To characterize antiretroviral therapy (ART) adherence across different programmes and examine the relationship between individual and programme characteristics and incomplete adherence among ART clients in sub-Saharan Africa.

Design—A cross-sectional study.

Methods—Systematically selected ART clients (≥18 years; on ART ≥6 months) attending 18 facilities in three countries (250 clients/facility) were interviewed. Client self-reports (3-day, 30-day, Case Index ≥48 consecutive hours of missed ART), healthcare provider estimates and the pharmacy medication possession ratio (MPR) were used to estimate ART adherence. Participants from two facilities per country underwent HIV RNA testing. Optimal adherence measures were selected on the basis of degree of association …


Explaining The "Pulse Of Protoplasm": The Search For Molecular Mechanisms Of Protoplasmic Streaming, Michael Dietrich Jan 2015

Explaining The "Pulse Of Protoplasm": The Search For Molecular Mechanisms Of Protoplasmic Streaming, Michael Dietrich

Dartmouth Scholarship

Explanations for protoplasmic streaming began with appeals to contraction in the eighteenth century and ended with appeals to contraction in the twentieth. During the intervening years, biologists proposed a diverse array of mechanisms for streaming motions. This paper focuses on the re-emergence of contraction among the molecular mechanisms proposed for protoplasmic streaming during the twentieth century. The revival of contraction is a result of a broader transition from colloidal chemistry to a macromolecular approach to the chemistry of proteins, the recognition of the phenomena of shuttle streaming and the pulse of protoplasm, and the influential analogy between protoplasmic streaming and …