Influence of subunit structure on the oligomerization state of light harvesting complexes: a free energy calculation study

Light harvesting complexes 2 (LH2) from Rhodospirillum (Rs.) molischianum and Rhodopseudomonas (Rps.) acidophila form ring complexes out of eight or nine identical subunits, respectively. Here, we investigate computationally what factors govern the different ring sizes. Starting from the crystal structure geometries, we embed two subunits of each species into their native lipid-bilayer/water environment. Using molecular dynamics simulations with umbrella sampling and steered molecular dynamics, we probe the free energy profiles along two reaction coordinates, the angle and the distance between two subunits. We find that two subunits prefer to arrange at distinctly different angles, depending on the species, at about 42.5 deg for Rs. molischianum and at about 38.5 deg for Rps. acidophila, which is likely to be an important factor contributing to the assembly into different ring sizes. Our calculations suggest a key role of surface contacts within the transmembrane domain in constraining these angles, whereas the strongest interactions stabilizing the subunit dimers are found in the C-, and to a lesser extent, N-terminal domains. The presented computational approach provides a promising starting point to investigate the factors contributing to the assembly of protein complexes, in particular if combined with modeling of genetic variants.Comment: 28 pages, 7 figures, LaTeX2e - requires elsart.cls (included), submitted to Chemical Physic

Evangelical Perspectives on Latino Immigration

Since 2006, a number of evangelical Christian leaders and organizations have become allies to the movement for comprehensive immigration reform in the United States. Starting with the historical context of the Civil Rights movement, this study will examine points of contact and divergence among the positions and practices of white, black and Latino evangelicals regarding the issue of Latino immigration. Notable nuances within and among the groups exist due to theological traditions, lived experience, socio-economic considerations and demographics. In order to become more effective allies in the comprehensive immigration reform movement, evangelical Christians need to address a number of challenges as individuals, churches, and denominations

Shadow of the Patriarch: Amanda Labarca Hubertson\u27s Views on North American/Latin American Relations

Amanda Labarca Hubertson (1886-1975) is recognized as one of Chile\u27s foremost thinkers, educators and feminist leaders of the 20th century. vVhile the genre of travel writing comprises only a small part of Labarca\u27s substantial writing career, the present essay under discussion, From Chile, represents the culmination of observations and reflections on North American and Latin American cultures derived from Labarca\u27s extended visits to the U.S. during the first half of the 20th century. Originally developed as an unpublished essay called Toward a Better Understanding ( Hada un entendimiento mejor ), this essay was included in the collection entitled As Others See Us: The United States Through Foreign Eyes, edited by Franz M. Joseph in 1959. (Paul 2/ 27) Like a number of other publications and activities sponsored by private pro-American foundations in years following World War II, this book containing Labarca\u27s essay was commissioned by an educational organization, the American-European Foundation, ostensibly as a vehicle to promote cultural understanding but also undoubtedly to defend North American culture. (Berghahn 416) For Labarca, however, it represented the opportunity to condense half a century of experiences and reflections into one essay with the goal of promoting hemispheric understanding and mutual respect

Cedarville University: Defining Legacies

Cedarville University’s 125th anniversary in 2012 provided an appropriate moment to look back and remember how God has led so many wonderful people to this place and how His hand has guided and kept us over all these years. As the university continues to grow and change, many individuals new to the campus—students, administrators, faculty and staff members alike—may not be aware of all the contributions of those who preceded them. In order to capture those lives before they are lost to history, Dr. Loach set out to record the stories behind some of the faces and names long associated with the university. In addition, she highlights how some of the university\u27s more than 30,000 alumni have served the Lord through various fields of endeavor around the world.https://digitalcommons.cedarville.edu/faculty_books/1181/thumbnail.jp

Cedarville University: Defining Legacies

Cedarville University’s 125th anniversary in 2012 provided an appropriate moment to look back and remember how God has led so many wonderful people to this place and how His hand has guided and kept us over all these years. As the university continues to grow and change, many individuals new to the campus—students, administrators, faculty and staff members alike—may not be aware of all the contributions of those who preceded them. In order to capture those lives before they are lost to history, Dr. Loach set out to record the stories behind some of the faces and names long associated with the university. In addition, she highlights how some of the university\u27s more than 30,000 alumni have served the Lord through various fields of endeavor around the world.https://digitalcommons.cedarville.edu/cedrus_press_publications/1017/thumbnail.jp

Cedarville University: Defining Legacies

https://digitalcommons.cedarville.edu/cedarville_university_histories/1009/thumbnail.jp

A Monte Carlo simulation of the Sudbury Neutrino Observatory proportional counters

The third phase of the Sudbury Neutrino Observatory (SNO) experiment added an array of 3He proportional counters to the detector. The purpose of this Neutral Current Detection (NCD) array was to observe neutrons resulting from neutral-current solar neutrino-deuteron interactions. We have developed a detailed simulation of the current pulses from the NCD array proportional counters, from the primary neutron capture on 3He through the NCD array signal-processing electronics. This NCD array Monte Carlo simulation was used to model the alpha-decay background in SNO's third-phase 8B solar-neutrino measurement.Comment: 38 pages; submitted to the New Journal of Physic

What do people do with porn? qualitative research into the consumption, use and experience of pornography and other sexually explicit media

This article reviews qualitative research into the consumption of pornography and other sexually explicit media emerging from a range of subject areas. Taking a critique of quantitative methods and a focus on measuring sexual effects and attitudes as a starting point, it considers the proposition that qualitative work is more suited to an examination of the complex social, cultural and political constructions of sexuality. Examining studies into the way men, women and young people see, experience, and use explicit media texts, the article identifies the key findings that have emerged. Qualitative work shows that sexuality explicit media texts are experienced and understood in a variety of ways and evoke strong and often contradictory reactions, not all of which are represented in public debates about pornography. These texts function in a range of different ways, depending on context; as a source of knowledge, a resource for intimate practices, a site for identity construction, and an occasion for performing gender and sexuality. The article reviews these studies and their findings, identifying what they suggest about directions for future research, both in terms of developing methodology and refining approaches to sexuality and media consumption.</p