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Spherical Invasion Assay: A Novel Method to Measure Invasion of Cancer Cells
No full textThe invasion of tumor cells into the neighboring blood vessels and lymph nodes is a vital step for distant metastasis. Traditionally, the invasive activity of growth factors (or the anti-invasive activity of drugs) is measured with the Boyden chamber assay. However, this assay has a few disadvantages like poor physiological relevance of transwell inserts and an inability to control chemokine gradients. The Boyden chamber assay is one of the most prevalent methods to measure the invasion of cancer cells. It would be advantageous to develop another assay that could validate the results of the Boyden chamber assay. With this in mind, our laboratory developed the spherical invasion assay (SIA) to measure the pro-invasive activity of human cancer cells. The SIA also circumvents some of the drawbacks of the Boyden chamber assay. The present manuscript measures the anti-invasive activity of the Src kinase inhibitor PP2 in A549 human non-small cell lung carcinoma (NSCLC) cells using the SIA. The SIA protocol is comprised of two steps. In the first step, A549 human NSCLC cells (treated or not with PP2) were mixed with Matrigel and seeded in the middle of an eight-well chamber slide. After 24 h, a second layer of Matrigel was overlaid over the first layer. Over the course of the next 24 h, the A549 cells invade from the primary to the secondary Matrigel layers. Subsequently, the cells are visualized by phase-contrast microscopy and the images obtained are quantified using ImageJ to calculate the anti-invasive activity of PP2 in A549 cells. The results of the SIA correlate well with Boyden chamber assays. The SIA may be adapted for multiple experimental designs, such as drug screening (to combat invasion and metastasis), measuring the pro-invasive activity of growth factors, and elucidating the signaling pathways underlying the pro-invasive/anti-invasive activity of biological modifiers
Matrix Tree Theorem for the Net Laplacian Matrix of a Signed Graph
No full textFor a simple signed graph G with the adjacency matrix A and net degree matrix D±, the net Laplacian matrix is L± = D±−A. We introduce a new oriented incidence matrix N± which can keep track of the sign as well as the orientation of each edge of G. Also L± = N±(N±)T. Using this decomposition, we find the number of both positive and negative spanning trees of G in terms of the principal minors of L± generalizing the Matrix Tree Theorem for an unsigned graph. We present similar results for the signless net Laplacian matrix Q± = D± +A along with a combinatorial formula for its determinant
The effect of Magnet Hospitals on nursing burnout
Get PDFIntroduction: Burnout has been a problem in health care for many years and it has particularly affected nurses. Nurse burnout was associated with worsened outcomes for nurses such as increased turnover or quitting and lower job satisfaction. There was a question as to how work environment and governance style influenced burnout.
Purpose of the study: The purpose of this research was to examine Magnet-designation status in U.S. hospitals, specifically shared governance and structural empowerment, and its effects on the rates of nurse burnout, nurse turnover, and job satisfaction of nurses.
Methodology: This study utilized a literature review. Four databases as well as Google and Google scholar were used to collect x total sources. The resources were reviewed, and y amount was used in the introduction and z amount in the results section. Two semi structured interviews were also conducted to gain perspectives from nurses.
Results: The results showed that overall, Magnet hospitals had lower levels of burnout, better job satisfaction, and less turnover compared to non-Magnet hospitals but this was not the case for every study of Magnet hospitals. Discussion/Conclusion: Magnet hospitals were generally associated with less burnout and better nurse outcomes but there was a lack of literature detailing specifically why. Some outcomes could be attributed to Magnet characteristics such as shared governance, but other factors could have also influenced their success. More research needed to be done to determine exactly why Magnet hospitals have reduced burnout and why some do not. The semi structured interviews supported the notion that organizational interventions needed to take place
How To Start a Colony, or Not: Different Models to Colonize Bermuda, Barbados and Tobago
Get PDFThis thesis considers three different and distinct models utilized by the British to colonize the Caribbean islands of Bermuda (1612), Barbados (1627) and Tobago (1763). Much has been written about the development of each one of these islands, yet it appears no study has drawn out and compared the varied development schemes employed by the British in these three instances. Such comparisons are appropriate since, unlike many other areas of British colonization, Bermuda, Barbados and Tobago were not, at the time the British arrived, occupied nor settled by indigenous people or other European settlers. This provided the British an opportunity to devise, develop and implement a settlement scheme that did not have to accommodate existing inhabitants on the islands. Given these blank slates for development, this thesis asks why three different models were utilized instead of one: was the first model not as useful and beneficial as the second and third? Some answers may be accessed by looking at the evolving political and economic climate in London where seventeenth century British adventurers and merchants making the decisions for Bermuda and Barbados eventually became the government bureaucrats calling the shots for the eighteenth century development in Tobago. However, in all three cases, despite the best of intentions and efforts by adventurers and bureaucrats, the resulting settlements did not meet their planners’ expectations. Distance between the colonies and Britain, coupled with the frailties and foibles of those appointed to implement the plans on the islands, thwarted the plans as designed. This leads one to mull over whether the problem was with the various models of colonization, or with the process of colonization itself
Teachers’ Perceptions of the NASA STEM EPDC Digital Badging System as a Model of Personalized Professional Development
Get PDFUnlike the ineffective generic approach often used for teacher professional development, NASA STEM Educator Professional Development Collaborative (EPDC) Digital Badging offers access to a highly organized system of knowledge and personalized, online professional development (PD) through digital badging. This qualitative case study provided an in-depth view of teacher perspectives of the value of NASA STEM EPDC Digital Badging as a model for personalized STEM professional development. The population for this study consisted of ten K-12 teachers, from a rural Southwest Virginia school system, who participated in the STEM-UP after school program and experienced PD through NASA STEM EPDC Digital Badging. Data from STEM-UP 2019 program evaluations and teacher responses from semi-structured interviews were used to inform this research. This study focused on teacher demographics, educational advantages and motivating factors that caused teachers to persist with the program, their perceptions of the badging for personalized learning and how the training fit into the over-all learning ecosystem. Data shows that teachers perceive the badge training as motivating, useful, personalized and effective as a form of PD that easily transfers learning into the classroom. Results of this study imply that NASA STEM EPDC Digital Badging was useful for the STEM-UP teachers and may be effective PD in other learning situations
Hope Agency and Hope Pathways as Potential Mediators of Trauma Exposure and Psychological Adjustment in Emerging Adults
Get PDFThe present study examined hope as a mediator between trauma exposure and negative affective conditions in 490 college students. Hope agency, but not hope pathways, mediated some of the association. Trauma exposure maintained a significant association with negative affective conditions. Implications for counselors working with trauma-exposed college students are discussed
George Bancroft\u27s sermons through the lens of his doctoral studies in Germany
No full textGeorge Bancroft\u27s sermons are virtually unknown, lost amongst his many more prominent activities and literary endeavours. This presentation aims to examine his sermons through the lens of his studies at the University of Goettingen.
Best known as a historian. George Bancroft (1800-1891) was also a politician and statesman (he served in London and Berlin as Minister Plenipotentiary). Appointed US Secretary of the Navy, he founded the US Naval Academy. In 1866 delivered a eulogy for President Lincoln having been selected by Congress to address both houses.
What is much less well known is that Bancroft, a Harvard graduate, who had worked toward his MA at the Harvard Divinity School, was awarded a scholarship to study at the University of Goettingen in Hanover. This serious studies he embarked on in Germany were foreseen as a way for him to prepare for the ministry and buttress his understanding of the Bible. The Georgia Augusta was one of the centers of the German Enlightenment and Bancroft\u27s coursework included some of the most well-known scholars in Europe at the time, including the acclaimed Professor Eichhorn who produced studies in biblical criticism and Professor Planck, a well-known historian of Christianity. Bancroft would eventually complete his studies in and take his doctoral degree from Goettingen and then listen to university lectures at Heidelberg and Berlin.
When Bancroft returned to the United States, he because a tutor in Greek at Harvard and made a tentative start on his career as a minister as Boston\u27s pulpits were open to him. He had promise as no less than Ralph Waldo Emerson called Bancroft one of the rising stars on our horizon after he had heard him preach. Bancroft would eventually co-found a school and then start on his political, scholarly, and diplomatic careers -- his sermons a faded memory. Yet, his sermons, unpublished, are not forgotten, and the aim of this paper is to examine those sermons in light of his training and studies in Germany