248 research outputs found
Antibacterial activity of root canal filling materials for primary teeth: zinc oxide and eugenol cement, Calen paste thickened with zinc oxide, Sealapex and EndoREZ
No full textThis study evaluated in vitro the antibacterial activity of 4 root canal filling materials for primary teeth - zinc oxide and eugenol cement (ZOE), Calen paste thickened with zinc oxide (Calen/ZO), Sealapex sealer and EndoREZ sealer - against 5 bacterial strains commonly found in endodontic infections (Kocuria rhizophila, Enterococcus faecalis, Streptococcus mutans, Escherichia coli and Staphylococcus aureus) using the agar diffusion test (agar-well technique). Calen paste, 1% chlorhexidine digluconate (CHX) and distilled water served as controls. Seven wells per dish were made at equidistant points and immediately filled with the test and control materials. After incubation of the plates at 37oC for 24 h, the diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a digital caliper under reflected light. Data were analyzed statistically by analysis of variance and Tukey's post-hoc test (?=0.05). There were statistically significant differences (p<0.0001) among the zones of bacterial growth inhibition produced by the different materials against all target microorganisms. K. rhizophila was inhibited more effectively (p<0.05) by ZOE, while Calen/ZO had its highest antibacterial activity against E. faecalis (p<0.05). S. mutans was inhibited by Calen/ZO, Sealapex and ZOE in the same intensity (p>0.05). E. coli was inhibited more effectively (p<0.05) by ZOE, followed by Calen/ZO and Sealapex. Calen/ZO and ZOE were equally effective (p>0.05) against S. aureus, while Sealapex had the lowest antibacterial efficacy (p<0.05) against this microorganism. EndoREZ presented antibacterial activity only against K. rhizophila and S. aureus. The Calen paste and Calen/ZO produced larger zones of inhibition than 1% CHX when the marker microorganism was E faecalis. In conclusion, the in vitro antibacterial activity of the 4 root canal filling materials for primary teeth against bacterial strains commonly found in endodontic infections can be presented in a decreasing order of efficacy as follows: ZOE>Calen/ZO>Sealapex>EndoREZ.</jats:p
Antibacterial activity of root canal filling materials for primary teeth: zinc oxide and eugenol cement, Calen paste thickened with zinc oxide, Sealapex and EndoREZ
No full textThis study evaluated in vitro the antibacterial activity of 4 root canal filling materials for primary teeth - zinc oxide and eugenol cement (ZOE), Calen paste thickened with zinc oxide (Calen/ZO), Sealapex sealer and EndoREZ sealer - against 5 bacterial strains commonly found in endodontic infections (Kocuria rhizophila, Enterococcus faecalis, Streptococcus mutans, Escherichia coli and Staphylococcus aureus) using the agar diffusion test (agar-well technique). Calen paste, 1% chlorhexidine digluconate (CHX) and distilled water served as controls. Seven wells per dish were made at equidistant points and immediately filled with the test and control materials. After incubation of the plates at 37oC for 24 h, the diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a digital caliper under reflected light. Data were analyzed statistically by analysis of variance and Tukey's post-hoc test (?=0.05). There were statistically significant differences (p<0.0001) among the zones of bacterial growth inhibition produced by the different materials against all target microorganisms. K. rhizophila was inhibited more effectively (p<0.05) by ZOE, while Calen/ZO had its highest antibacterial activity against E. faecalis (p<0.05). S. mutans was inhibited by Calen/ZO, Sealapex and ZOE in the same intensity (p>0.05). E. coli was inhibited more effectively (p<0.05) by ZOE, followed by Calen/ZO and Sealapex. Calen/ZO and ZOE were equally effective (p>0.05) against S. aureus, while Sealapex had the lowest antibacterial efficacy (p<0.05) against this microorganism. EndoREZ presented antibacterial activity only against K. rhizophila and S. aureus. The Calen paste and Calen/ZO produced larger zones of inhibition than 1% CHX when the marker microorganism was E faecalis. In conclusion, the in vitro antibacterial activity of the 4 root canal filling materials for primary teeth against bacterial strains commonly found in endodontic infections can be presented in a decreasing order of efficacy as follows: ZOE>Calen/ZO>Sealapex>EndoREZ.Este estudo avaliou in vitro a atividade antibacteriana de 4 materiais obturadores de canais radiculares de dentes decíduos - cimento de óxido de zinco e eugenol (OZE), pasta Calen espessada com óxido de zinco (Calen/OZ), cimento Sealapex e cimento EndoREZ - sobre 5 cepas bacterianas comumente encontradas em infecções endodônticas: Kocuria rhizophila, Enterococcus faecalis, Streptococcus mutans, Escherichia coli e Staphylococcus aureus, usando o teste de difusão em ágar (técnica do poço). A pasta Calen, digluconato de clorexidina a 1% (CHX) e água destilada foram usados como controle. Sete poços por placa foram preparados em pontos eqüidistantes e imediatamente preenchidos com os materiais experimentais e controle. Após incubação das placas a 37oC por 24 h, o diâmetro dos halos de inibição do crescimento bacteriano formados ao redor dos poços foi medido (em mm) com um paquímetro digital sob luz refletida. Os dados obtidos foram submetidos à análise de variância e ao pós-teste de Tukey (?=0,05). Com relação à atividade antibacteriana, evidenciaram-se diferenças estatisticamente significantes (p<0,0001) entre os halos de inibição formados pelos diferentes materiais, para todos os microrganismos avaliados. A K. rhizophila foi inibida mais eficazmente pelo OZE (p<0,05), enquanto que o E. faecalis foi inibido mais eficazmente pela Calen/OZ (p<0,05). O S. mutans foi inibido pela Calen/OZ, cimento Sealapex e OZE na mesma intensidade (p>0,05). A E. coli foi inibida mais eficazmente pelo OZE, seguido pela Calen/OZ e pelo cimento Sealapex (p<0,05). O S. aureus foi inibido pela Calen/OZ e OZE na mesma intensidade (p>0,05), e menos intensamente pelo cimento Sealapex (p<0,05). O cimento EndoREZ apresentou atividade antibacteriana apenas frente a K. rhizophila e ao S. aureus. A pasta Calen e a Calen/OZ ocasionaram halos de inibição maiores que a CHX quando o microrganismo indicador foi o E. faecalis. Pode-se concluir que a atividade antibacteriana, in vitro, dos 4 materiais obturadores de canais radiculares de dentes decíduos sobre cepas bacterianas comumente encontradas em infecções endodônticas pode ser apresentada numa ordem decrescente de eficácia da seguinte maneira: OZE>Calen/OZ>Sealapex>EndoREZ
2016 Fall Honorable Mention
No full textHonorable Mention MENTIONING WESTMINSTER HONORABLES SINCE 2002 First lateral-entry cohort joins the Honors program New system welcomes transfer and sophomore students to honors The first lateral-entry cohort participates in a discussion led by professor Nick More. Lateral-entry students take the introductory course “Welcome to Thinking III,” which stands in place of Welcome to Thinking I and II offered for traditional-entry students. Photo courtesy of Calen Smith By Stephanie Held Orange textbooks sit face-up in front of each student, joined by coffee cups and water bottles. It’s 10 a.m., which means little morning light filters through the classroom’s four small windows. In fact, most of the space is lit by overhead fluorescents. When the door is shut, noise from the hallway ceases and Gore 108 becomes its own world. Conversation begins as everyone sits around the circle of tables. All the seats are full in Welcome to Thinking III, the new gateway seminar for lateral-entry students joining the Honors program. The Honors Council began discussing a lateral entry option in 2013 in conjunction with the larger curricular reform process at Westminster. By 201415, eight students were participating in Honors classes as part of a studentdriven pilot program. Encouraged by the positive experiences of these pilot students, the Honors Council created an official lateral entry option for a fall 2016 start. “ You get a lot more e x perience and pers pect ive and you als o get people who really want t o be t here....” Olivia Perez The lateral entry option was designed to offer the Honors experience to students who were unable or uninterested in applying via the traditional entry route. This new pathway makes Honors welcoming to Fall 2016 - Volume 15 - Issue 1 all types of students and adds different life experiences to classroom discussions, according to Honors Director Richard Badenhausen. Many Honors students also said it’s a positive expansion of the program. “I think [lateral entry] is good for the Honors program,” said Olivia Perez (‘18), one of the original pilot students. “You get a lot more experience and perspective and you also get people who really want to be there, and I think that adds to the experience.” The first formal lateral-entry cohort joined the Honors program this fall, comprised of internal and external transfers, a group made up of traditional age students, adult learners, international students, and veterans. Despite their varied backgrounds, these students were brought together by their shared motivation and dedication to academics. Continued on page three Honors students create first global awareness conference Elhom Gosink and Tim Lindgren spearhead campus global community By Catherine Blakemore In the spring of 2016, two Honors students pioneered an undergraduate research conference called “Global Crises Global Change” (GCGC). Honors student Tim Lindgren, a senior from Sweden, was one of the conference’s co-founders, alongside Honors senior Elhom Gosink. Westminster junior Luis Mario Ruiz joined the team in fall 2015. Lindgren, previously quoted in an article by The Forum: Westminster College’s Student News Source, said he had desired for a long time to create a conference to address global challenges and provide a space for cross-disciplinary and cross-cultural multilateral knowledge exchange. The purpose of the conference, as noted in the GCGC agenda booklet, was to address roots of convergent global crises, creatively explore possible solutions and alternatives, and collaboratively facilitate connections across multiple campuses, communities, organizations, and social groups. Gosink indicated that several local NGOs and other organizations were invited to host an informational table throughout the conference. “Students and community members were able to make connections with these organizations who are committed to change in our community,” Gosink said. “Many of these organizations have expressed an interest in continuing their relationship by coming to future conferences.” The Westminster College Griffin Grant funded the 2016 conference, awarded to Lindgren and Gosink after they applied for the grant during the spring 2015 Honors seminar “Political Economy of Conflict.” The four-day conference consisted of five panels and roundtable discussions with students from Westminster College, Utah State University, Brigham Young University, Northern Arizona State University, and Boise State University. Westminster juniors Cozy Huggins and Josie Stoker presented their work “Political Studies Don’t Have to be so 2 Seniors Elhom Gosink and Tim Lindgren collaborate in the planning of the first ever Global Crisis Global Change Conference. This event, focusing on fostering a global community, took place in spring 2016. Photo courtesy of Catherine Blakemore Goddamn Heterosexual: Your Mindset is Exhausting and We’ve had Enough” in the fourth panel on gender and sexuality. They said the GCGC was an amazing opportunity for students to present research in an academic setting, though certain topics did lack proper representation or were addressed in ways that ignored intersectional perspectives. “ St udent s from t his year’s conference have crea t ed connect ions t hat will cont inue t o grow this conference and link with ins t it ut ions around t he count r y.” Elhom Gosink “We are very excited to have had this opportunity and were impressed by how smoothly the conference ran and how well organized it was,” Huggins said. “We were presenting on gender and sexuality minorities in political science and the need to include these intersectional voices. It was very empowering to have the chance to discuss ideas that affect our community and come up with ways to make those voices more intersectional.” They both indicated that they look forward to the future of the conference under the political science department and hope the future will bring more intersectional voices. “The conference provided a space for students to practice presenting in an academic fashion and meet with [others] from an array of majors and schools who might not otherwise have a platform to meet and learn from one another,” Gosink said. “They formed academic and personal relationships with one another. Students from this year’s conference have created connections that will continue to grow this conference and link with institutions around the country.” The global community the GCGC fostered wouldn’t have been possible without the ambition and dedication of these Honors students. GCGC cofounder Gosink said plans are already in motion to ensure the conference continues after she and Lindgren graduate. Both Honors seniors said they hope the conference will continue to provide a critical platform year after year for the community to foster personal and institutional relationships. Popich and Badenhausen reflect on Honor’s growth Program founder and current director share changes in curriculum and structure over last 29 years By Elizabeth Johnson Several key changes have shaped the course of Westminster’s Honors program since its founding in 1987. As the program moves toward more flexible curricular paths for students and different modes of entry into the program, the Honors program’s founder and original director, Dr. Michael Popich, and current director, Dr. Richard Badenhausen, reflect on the program’s journey. One of the key turning points for the program was when Dr. Nick More, the program’s second director, created the Honors Council with the goal of bringing an endowed chair to the program. Badenhausen said he credits this event with bringing him to campus. Likewise, Popich said he identifies Badenhausen taking over as director as a major turning point for the Honors program, since it has gained more national recognition under Badenhausen’s leadership. Popich described what Badenhausen has done with the program as “remarkable.” Another major shift for Honors was its establishment in Nunemaker Place at the beginning of the fall semester in 2004. Prior to the move, the program had no space to call its own. Having a physical location to host both academic and social events altered the atmosphere of the program, creating a stronger sense of community and a greater awareness of fellow students in the program, Continued from page one Lateral-entry students “know what it’s like to be in college and have had certain experiences with college level-classes,” said Sara D’Agostino (‘19), an internal transfer student originally from Milan, Italy. “But we still decide that we want more.” Before joining the cohort, students must have had at least 8 hours of general education credit, though most have many more. They are then required to take Welcome to Thinking III—co-taught this according to Badenhausen and Popich. The Honors program is now a community rather than just a set of courses for academically prepared students as it was in earlier years, Popich said. This sense of community is also fostered by a robust peer mentoring program, events hosted by the Student Honors Council, and Tuesday Conversations—events and opportunities that weren’t around 20 years ago. In recent years, the course of the Honors program has shifted yet again as its curriculum has been made more flexible. A curricular change two years ago resulted in the creation of new, redesigned classes to better meet student needs, as well as the lateral entry option, which offers multiple pathways to completing the program. With these changes in curriculum, both Badenhausen and Popich said they’ve noticed that the number of Honors faculty has grown and the professors have become more excited about team teaching and interdisciplinary thinking. When the program began, there were only 10 to 12 faculty members teaching. There are now 28 faculty members who regularly rotate through the Honors curriculum. Both Badenhausen and Popich said they look forward to seeing how eventually turning the program into an Honors college will grow and shape Honors in the near future. Over the past 29 years, the honors program has had three directors: Michael Popich, Nick More and Richard Badenhausen. One of the newest proposals for growth is the development of a new honors college that would allow for more students and faculty to participate in the program. Cartoon by Jessica Taghvaiee fall by anthropology professor Connie Etter and philosophy professor Nick More— as well as three additional Honors core seminars. Students who complete these requirements earn the Honors Certificate. As the Honors program works to promote Westminster’s goal of a more diverse and inclusive campus, senior global studies major Tim Lindgren (‘17) said the lateral entry program is a step in the right direction. This option offers another opportunity for high-achieving students to join a supportive community of like minded people, said Jen Youngblood (‘20), a psychology major and transfer student from Washington. In short, the expansion of the Honors program has both students and faculty excited for the future. “[Welcome to Thinking III] is a great experience so far,” said Jared Rich (‘18), an external transfer student to the Honors program from Salt Lake Community College. “I mean, it’s only been a couple weeks and I’m already calling it my favorite class ever. So yeah. It’s pretty cool.” 3 #ThrowbackThursday Professors look back on the good ol’ days. Phone books, old cars and poofy hair. By Aaron Smith Throwback Thursday (TBT)—a day when Honors students run to their computers to compete in the field of (online) glory to find out who can correctly guess the following about a photo posted on the Honors program’s Facebook page: 1) the Honors faculty member in the photo, 2) the year the photo was taken, and 3) the circumstances surrounding the picture. As an exemplar of staying true to your passion despite external pressures is Dave Goldsmith. This photo gives a brief glance into the life of a young Goldsmith, whose side job was almost certainly running an underground gambling ring. Honors sophomore Calen Smith commented this photo shows Goldsmith “checking the books.” We personally are looking forward to Goldsmith’s Tuesday Conversation “Underground Gambling and You.” David Goldsmith Attempts to find help from a barber, a tailor and a personal trainer with Siri’s predecessor: the phonebook. 25 years ago Like Fashion is another passion of the Honors community. Inspired by Heidi Van Ert’s photo, Goldsmith posted that Heidi and her stylish ski-wear of 1971 “proves the axiom that fashion is wearable art.” Whenever first-year Honors students wonder, “How am I going to write a prompt relating a 21st century axiom and fashion?” they need look no further than Goldsmith’s wise words. Heidi Van Ert Sporting the team uniform for the learn-to-race ski program at snowbird. Praying for snow. 45 years ago Like Michael Chipman invited the Honors community to remember the fading fashion of puka shells. The (un)official winning comment on this post was from Marya Tykal, who wrote, “Michael Chipman, around 1995, taken in a brief pause from fending off the hordes of high school girls drawn in by the puka shells.” Chipman responded, “Don’t underestimate the power of puka shells and hair gel, people.” Throwback Thursday has become a staple of the Honors program and is here to stay. We may not have any SNL Writers in the Honors program, but we do have Throwback Thursday comments. Michael Chipman Rocking puka shells and an entire jar of hair gel. Some school pictures do leave the yearbook. 27 years ago Like 4 Honors diversifies program’s experience with new seminars By Calen Smith and Maggie Fischer Students engage in lively discusion in Data, Society and Decision Making, led by professors Sean Raleigh and Julie Stewart. Photo Courtesy of Calen Smith CAPSTONE CONVERSATIONS The Honors program has recently undergone many exciting curriculum reforms with both new and existing classes providing more flexibility and variety for Honors students. Classes such as Environments and the Space of Art, Welcome to Thinking III, Capstone Conversations, and Data, Society, and Decision Making, are brand new to the Honors program. Meanwhile, existing classes have also changed, including Tuesday Conversation (formerly Living Arts) and Global Welfare and Justice (formerly Political Economy of Conflict). Finally, a course that returns once every four years, Presidential Elections: Strategy and Substance, was offered for fall 2016. Richard Badenhausen, director of the Honors program, said he welcomes the curriculum changes. “We’ve been waiting for a while for college-wide gen-ed reform so we could try new things we have been excited about,” he said. The Honors program will offer the Capstone Conversation course in the 2019–2020 school year, with a potential pilot course in the 2018–2019 year. Capstone Conversations will be informed by students’ thesis work across many disciplines and will draw on the skills they have learned over the course of their college career. The course will also provide an opportunity for senior students to reconnect with their firstyear cohort right before graduating. TUESDAY CONVERSATIONS Living Arts, now known as Tuesday Conversations, was originally designed as a lab to Humanities I to satisfy the college-wide living arts requirement. With Westminster’s removal of the Living Arts requirement during the adoption of the new WCore, Honors had the option of removing the two-hour discussions every Tuesday night. However, in the spirit of providing a weekly community-building opportunity for the entire Honors first-year cohort and information they may not learn in the classroom, Living Arts evolved into Tuesday Conversations while still being attached to Welcome to Thinking. 5 Utah politicians Roger Livingston and Ted Wilson act as professors for an honors semoinar following the presidential election. This class is only offered every four years and provides students the opportunity to hear from prominent local politicians, while closely following the race for the White House. WELCOME TO THINKING III The introductory seminar sequence known as Humanities I & II is now called Welcome to Thinking I & II. Alongside these courses, the brand new Welcome to Thinking III seminar is available to lateral-entry students and follows a similar format. Welcome to Thinking III is a one-semester offering because many lateralentry students have already completed a significant number of general education requirements upon entering the Honors program. Much of what takes place in the introductory class to Honors has stayed the same, such as interdisciplinary course design, student-centered discussions of primary texts, and weekly writing of prompts. One reason for transitioning away from the “Humanities” title is that readings from these seminars now encompass non-Western texts and are drawn from a wide variety of eras and disciplines, including examples like “Medieval Islamic philosophy and Ancient Asian drama,” according to Badenhausen. A past Honors student looking over the syllabus of Welcome to Thinking III, for example, might be surprised to find readings like Freire’s “The Banking Model of Education” and Paul Cottell Jr.’s “A Queer Youth.” Despite the curriculum changes, the classes maintain their familiar focus on reading, writing, and discussion. Photo Courtesy of Calen Smith content now covered in the class. Cain, who taught one semester of Global Welfare and Justice, said she enjoys teaching in Honors. “It is exciting to be a part of a program that is continually updating curriculum and moving in more interdisciplinary ways,” she said. Global Welfare and Justice is just one example of that movement. GLOBAL WELFARE AND JUSTICE PRESIDENTIAL ELECTIONS: STRATEGY AND SUBSTANCE Global Welfare and Justice is another Honors seminar that has undergone changes in name and content. The class, which was originally called Political Economy of Conflict, focuses on different ideologies and philosophies and analyzes how economic decision making occurs within political systems. Professors Leonardo Figueroa-Helland and Peggy Cain coteach the Global Welfare and Justice course in the spring semester while Michael Popich and John Watkins run the fall version. Figueroa-Helland has taught the course a few times and said he noticed that “the class moved into a different sort of approach with more emphasis on engaging contemporary global issues, welfare, environmental issues, diversity of perspectives, culture, gender, race, and class.” The natural transition Figueroa-Helland described shows how the new title more accurately reflects the Offered once every four years in concurrence with U.S. presidential elections, the Presidential Elections: Strategy and Substance class is one of the most distinct courses in the Honors program. The two professors teaching the course this election, Roger Livingston and Ted Wilson, are experienced Utah politicians who also have taught regularly at the college level. Livingston is a former judge for the third district court in Utah and served two terms as a representative in the Utah State Legislature. Wilson served as mayor of Salt Lake City for three terms and used to direct the Hinkley Center for Politics at the University of Utah. Livingston, who has returned to teach the class through four election cycles said, “This class has the value of being current. We are learning about things 6 that have immediate application, where everything is important—from Trump’s tax issues to Clinton’s email scandal. We are teaching the present.” Both professors said they hope the class gets students interested in politics and helps them become more active, informed, and caring citizens. “Politics is a big slice of life,” Ted said. “By learning about politics, you become aware of how we solve problems, how we get to what’s important, how we project ourselves, and how we get along with others.” ENVIRONMENTS AND THE SPACE OF ART As the Honors program diversifies, it has introduced new classes to fill growing demands for a wider range of subjects. In an effort to bring in new topics that were not previously covered by the curriculum, the program decided to pair environmental science and art. Environments and the Space of Art was introduced as a cross-listed, special topics course in fall 2015 and will be offered again in spring 2017 by art hisDATA, SOCIET Y, AND DECISION torian and land art expert Hikmet Loe and art professor Matt Kruback. Environmental studies professor Brent Olsen, who MAKING co-taught the first version of the seminar, said the class cenData, Society, and Deci“ By lear ning about polit ics , you ters on how the environment sion Making was first offered become aw are of how we s olve and art interact—both what art in spring 2015. That seminar can teach us about the environproblems , how we get t o what’s arose out of a desire to incorporate more quantitative-based impor tan t, how we project ours elves , ment and how the environment can influence the art created in courses into the Honors proan d how we get along w it h ot hers .” it. Like many Honors classes, gram. Sociology professor JuEnvironments and the Space of lie Stewart and public health Art allows students to choose professor Han Kim taught the Ted Wilson subjects of interest and explore original iteration of the course, them beyond what a traditional which was designed by a group classroom setting might allow. of QUARC faculty and students led by math professor Sean The changes in Honors curriculum reflect the program’s Raleigh. This semester, Stewart and Raleigh are teaching the commitment to meet growing demands for new and modified course. Like every Honors class, the curriculum varies semesclasses. The Honors progr
Cytotoxicity analyses of filling materials for primary teeth
No full textOrientador: Fernanda Miori PasconDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Endodontia em dentes decíduos é um procedimento de suma importância para manter a integridade e saúde dos dentes e tecidos de suporte. Sendo assim, o uso de materiais obturadores de canais radiculares que apresente o máximo de propriedades desejáveis é indispensável. O objetivo do presente estudo foi analisar a citotoxicidade de diferentes materiais obturadores em fibroblastos do ligamento periodontal humano (PDL) e em células osteoblásticas de osteossarcoma humano (Saos-2). Os fibroblastos foram cultivados em meio de cultura (meio Eagle modificado por Dulbeco - DMEM) suplementado com 1% soro fetal bovino (FBS) e antibióticos. Os osteoblastos foram cultivados em meio de cultura McCoy¿s suplementado com 15% FBS e antibióticos. Próximos de atingir a confluência, as células foram plaqueadas na concentração de 7x103 células por poço e foram expostas aos seguintes materiais, conforme os grupos: G1- Meio de cultura sem material obturador (controle negativo), G2- Dimetiilsulfóxido (DMSO) (controle positivo), G3- Calen®, G4- Calen® associada ao Óxido de Zinco, G5- Calen® associada ao Iodofórmio, G6- Óxido de zinco e eugenol (OZE), G7- Vitapex® e G8- UltraCal®XS. A manipulação dos materiais foi realizada em condições assépticas. A citotoxicidade dos materiais obturadores foi analisada em intervalos de tempos (8, 24 e 48 horas) pelo método de redução MTS e classificado como não citotóxico, citotoxicidade leve, moderada e grave. O grupo controle negativo foi composto apenas por células, sem o uso de material obturador. A análise morfológica das células foi realizada por meio da microscopia de fluorescência. Os dados obtidos foram submetidos à análise de variância dois fatores e ao teste Tukey para comparação entre os grupos, com nível de significância 5%. As imagens obtidas por meio da microscopia de fluorescência foram analisadas de forma descritiva. Os resultados mostraram que para os fibroblastos, Calen®(85,91±10,01), Calen® associada ao Óxido de Zinco (85,91±8,16) e Calen® associada ao Iodofórmio (83,96±13,95) diferiram do controle negativo (100±0) e positivo (19.72±5,70) após 8 horas de exposição. Para os osteoblastos, Calen® associada ao Óxido de Zinco (75,87±19,16), Calen® associada ao Iodofórmio (75,5±12,40) e o OZE (68,71±22,19) foram os únicos grupos que em 8 horas diferiram do controle negativo (100±0) e positivo (22,18±6,77). Pode-se concluir que todos os materiais avaliados, para fibroblastos do ligamento periodontal humano, não foram citotóxicos ao longo do tempo. No entanto, Calen® associada ao Iodofórmio apresentou toxicidade leve em 48 horas para os osteoblastos. Vitapex® foi o material que apresentou menor toxicidade celular nos osteoblastos em 8 e 48 horas, comparando-se os outros materiais avaliados. Calen® associado ao Óxido de zinco, Calen® associado ao Iodofórmio e OZE foram capazes de modificar a morfologia dos fibroblastos, mas para os osteoblastos não foram observadas alterações morfológicasAbstract: Endodontics in primary teeth is an important procedure to maintain the integrity and health of the teeth and supporting tissues. Using a root canal filling material that shows desirable properties is indispensable. The aim of the present study was to evaluate the root filling materials cytotoxicity on periodontal ligament fibroblasts (PDL) and osteoblastic human osteosarcoma cells (Saos-2). Fibroblasts were cultured in culture medium (Dulbeco modified Eagle medium - DMEM) supplemented with 1% fetal bovine serum (FBS) and antibiotics. The osteoblasts were cultured in McCoy's culture medium supplemented with 15% FBS and antibiotics. Next to reach confluence, the cells were plated at a concentration of 7x103 cells per well and were exposed to materials, according to the groups: G1 - culture medium without filling material (negative control); G2- Dimethyl sulfoxide (DMSO) (positive control); G3 ¿ Calen®; G4 - Calen® associated with Zinc Oxide; G5 - Calen® associated with Iodoform; G6 ¿ Zinc Oxide and eugenol (ZOE); G7 - Vitapex®; G8 - UltraCal® XS. The materials were prepared under aseptic conditions. Cytotoxicity was evaluated by cell viability at time intervals (8, 24 and 48 h) by MTS assay and rated as non-cytotoxic, mild, moderate and severe cytotoxicity. The negative control group was composed only of cells without the use of filling material. Cells morphological were observed by fluorescence microscopy. Data were submitted to two-way analysis of variance with post-hoc comparisons base on Tukey's multiple comparisons, with the significance level fixed at 5%. The images obtained at fluorescence microscopy were evaluated using descriptive analysis. The results showed that for fibroblasts, Calen®(85.91±10.01), Calen® associated with Zinc Oxide (85.91±8.16) e Calen® associated with Iodoform (83.96±13.95) was differ from the negative control (100±0) and positive (19.72±5.70), at 8 h. For osteoblasts, Calen® associated with Zinc Oxide (75.87±19.16), Calen® associated with Iodoform (75.5±12.40) and ZOE (68.71±22.19) differed from negative control (100±0) and positive (22.18±6.77) in 8 h. It can be concluded that all materials were non- cytotoxic to human fibroblasts cells over time. However, Calen® + Iodoform showed higher cytotoxicity to osteoblasts at 48 h. Vitapex® was the material that showed the less cell cytotoxicity in osteoblasts at 8 and 48 h, compared to the other materials tested. Calen® associated with Zinc Oxide, Calen® associated with Iodoform and ZOE was able to modify the morphology of fibroblasts, but osteoblasts but no morphologic alterations were observedMestradoOdontopediatriaMestra em Odontologi
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No full textAufnahme nach: ÖNB-InkLagen: a-c8Vorlageform des Erscheinungsvermerks: Erhardi ratdolt Avgustensis perpolita arte impressa extant. Xii. calen. Nove[m]bris Anno Salutis. M.cccc.lxxxj. VenetijsGW 8997HCR H 6378ISTC id0032777
2017 Spring The Honorable Mention
No full textHonors student and grant recipient, Warren Cook [left], poses on a road trip during summer research in the Snake Valley. Photo Courtesy of Warren Cook Honors students take the lead in environmental research B Y: E R I C M E L L M E R & D I A N A K H O S R O V I cultural values.’ I really tried to unearth the cultural value of water Warren Cook and Tim Lindgren, recipients of last year’s Hon- through my twenty oral interviews.” ors Independent Summer Research Grant, conducted separate reCook says he hopes his qualitative research will contribute to search projects during the summer of 2016 that addressed the role existing scientific research on the potential environmental damage of ecological destruction in human lives. a water grab could have. “If we can better Focusing on a local scale, senior histounderstand the connection that we hu“If we can better understand the ry major Cook conducted research in the mans have with the planet, maybe we’ll connection that we humans have Snake Valley between Utah and Nevada think twice before destroying it,” Cook to explore the effects a water grab would observes. with the planet, maybe we’ll think have on the valley’s residents. He credits his successful research twice before destroying it.” Cook spent July 2016 living in a to Abby Johnson, director of the Great school bus next to the alfalfa fields owned Basin Water Network; to his aunt and by his uncle, Ed Alder. During his stay, uncle, Deana and Ed Alder; and to proWarren Cook he traveled the 100-mile long valley to fessors Jeff Nichols, Gary Marquardt, conduct twenty in-depth interviews with Lance Newman, and Brent Olson. residents about the relationship between water, people, and the Cook expressed gratitude for his research opportunity, which landscape. refined his people skills and gave him confidence in his ability “I used a theoretical framework outlined by Dan Flores (an en- to spearhead future independent research during his graduate vironmental historian) to get at what he calls the ‘spirit of place,’” school studies. Cook says. “Flores says, ‘What generates the spirit of place are Continued on Page 11 PAGE FOUR PAGE FIVE DAVE GOLDSMITH The end of an era as assistant director of Honors and the development of a new major 1 STUDENT LEADERS Honors student (over) involvement with on-campus leadership roles Honors Director Wins National Award for Leadership Badenhausen accepted the Sam Schuman Award for Excellence for work in and outside the classroom B Y: E L A I N E S H E E H A N Richard Badenhausen, director of Westminster’s Honors program, assumed the role of National Collegiate Honors Council (NCHC) Vice President in Fall 2016. The NCHC is the membership organization of approximately 900 Honors programs and colleges around the country and abroad. Shortly before, he accepted the Sam Schuman Award for Excellence at a Four-Year Institution, which is awarded annually to one NCHC Honors director or faculty member for outstanding contributions to their four-year honors program. Though this national recognition is a major success for both Badenhausen and the Honors program, it did not come as a surprise to the many students and faculty who work with the college’s Honors director. Since 2002, when Salt Lake City hosted the NCHC annual conference, Badenhausen has served as a member of multiple NCHC committees, including the organization’s board of directors. He has also worked as a co-chair of the Publications Board, which oversees all NCHC publications, and as a consultant on best practices in Honors education, advising over a dozen other Honors programs and colleges across the country. “Become a good listener.” Richard Badenhausen On advice to aspiring leaders Badenhausen said NCHC “energized our Westminster community in a way that helped us understand the value of getting involved in the national opportunities to connect— especially when it came to student involvement.” Through Badenhausen’s guidance, students have had the opportunity to take advantage of the professional development opportunities provided by the program’s NCHC affiliation, such as publishing undergraduate research and attending the annual NCHC conference. Badenhausen and students have said these opportunities foster appreciation for the distinctiveness of the Westminster Honors program while simultaneously generating innovative ideas for how to improve. Fueled by a strong national network and a student-centered value system, Badenhausen is leading the Honors program into an exciting new time of growth. Once the transition from Honors program to Honors college is complete, Badenhausen will become the dean of the college—though he said his leadership methods won’t change much. Badenhausen said he will continue to focus on helping first-year students make a smooth transition to college and discover their Photo Courtesy of Elaine Sheehan interests and leadership potential early on. He said he will also continue to teach the first-year seminars, allowing him to connect with the majority of students in each cohort, which he said he sees as one of the most important parts of his role. Though Badenhausen’s national recognition demonstrates the quality of Westminster’s program under his leadership, he said his most rewarding moments in Honors are not the awards but the ability to “work with students and see them accomplish things they couldn’t conceive of when they arrived at the college and to know that they’ve had a transformative experience through the opportunities they have here.” The Westminster Honors community is grateful for Richard’s dedication to the program and his successes both on a national level and in his everyday interactions with individual students in the program and looks forward to his continued successes as the Honors dean. 2 Honors student, Holden Rassmussen [left], discussing political theory with philosophy professor Kara Barnette. Photo Courtesy of Elaine Sheehan Philosophy professors speak about what characteristics and qualities make a good leader B Y: H O L D E N R A S S M U S S E N The theme of this semester’s Honorable Mention is leadership. A theme is a unifying element of a work that situates the piece in a familiar, broad idea to ease the transmission of the author’s ideas to the reader. Of course, we should not leave themes unexamined, because we then risk conveying nothing more than an empty husk of a buzzword, with the vague aim of marketing something to someone. That’s why we’ve asked our neighborhood philosophers to weigh in on this semester’s theme by asking them, “What makes a good leader?” Here are their responses for your rumination. “[It is] [d]ifficult to resist reprising Nietzsche’s aphoristic remark on leaders/leadership, so I won’t: Vademecum—Vadetecum Lured by my style and tendency, You follow and come after me? Follow your own self faithfully— Take time—and thus you follow me.” (Friedrich Nietzsche, The Gay Science, from the prelude “Joke, Cunning and Revenge”) “I like to think that the key to effective leadership is character. How do you behave when you think nobody is looking? What kinds of actions define you? Character is what’s ingrained and automatic and it implies a harmony between word and deed. No doubt the last 20 years have seen their fair share of corporate executives who at work stand and smile by statements of company integrity while at the same time enjoy personal lives of extravagant greed and reckless behavior. We then wonder why the companies they run are so rife with corruption and illegal practices. As Kung Fu-tzu, commonly known in the West as Confucius, put it 2,500 years ago: ‘If the ruler himself is upright, all will go well even though he does not give orders. But if he himself is not upright, even though he gives orders, they will not be obeyed.’” Michael Popich “Philosophers are doing their jobs when they annoy and question ‘leaders’— not when they are trying to emulate ‘leaders.’ In fact, some of us (like me) actually find the aim of building ‘leaders’ incredibly problematic.” Kara Barnette “The Sage Helps all beings find their nature, But does not presume to act.” (Lao Tzu, Tao Te Ching, #64) Nick More Jason Goltz 3 FAREWELL, DAVE The Man, the Myth, the Honors assistant director steps down to build new Geology major “Dave is one of the smartest, “When humans dam a river funniest guys I know. Dave has people say we’re ‘playing god.’ been a great partner in Honors When beavers do it, they don’t over the nine years... He’s even get accused of playing going to be missed greatly.” human.” Richard Badenhausen Dave Goldsmith “Spending four hours a week with Dave in class is a rollicking experience... Class is sometimes hard—and sometimes plain bonkers— but it’s always an experience nobody will forget.” Christine Seifert B Y: A S H L E I G H A L B R E C H T S E N Geology professor Dave Goldsmith’s distinctive approach to teaching—an integration of fresh perspectives, tangible examples, and witty humor—has enriched the Honors community for the past fourteen years. Through Honors courses like Science as Knowledge, Goldsmith offers ideas accessible to students of all disciplines. His expertise might intimidate some if it wasn’t tempered by sharp jokes, amusing references, and engaging enthusiasm. As assistant director of the Honors program for the past nine years, Goldsmith has ensured Honors students cultivate curiosity beyond their seminars by overseeing many student-centered programs like Tuesday Conversations, Honors orientation, and the annual Honors writing awards. Additionally, he has coordinated Academic Decathlon, which provides Utah high school students the opportunity to connect with Honors students on campus. At the same time Goldsmith has devoted significant energy to the Honors program, he has also helped form Westminster’s new geology major, which he will now continue to develop by serving as the department’s faculty chair. As Goldsmith departs from his position as assistant director of Honors, we thank him for his contributions and look forward to his teaching in Honors classrooms for years to come. 4 Honors in Action: Campus leaders and pioneers Hannah Fasiang demonstrates how to make kombucha at an American Chemical Society event. Photo Courtesy of Calen Smith B Y: M A G G I E F I S C H E R A N D E L I Z A B E T H J O H N S O N Hannah Fasiang, a fourth-year pre-med student, works as a peer mentor for other pre-med students and serves as one of three presidents for the ACS (American Chemical Society) chapter on campus. Fasiang has been involved with ACS since her first year of college and she credits Robyn Hyde—the society’s faculty adviser, chair of the chemistry department, and pre-med adviser—with equipping her with the tools she needed to take on an ACS leadership position. Fasiang says she values her leadership role, which has taught her how to work with young children through club outreach—a skill she says will be valuable as she pursues her dream of treating all ages as an emergency room doctor. In addition to developing new leadership skills, Fasiang says the most rewarding part of ACS has been seeing her mentees “blossoming and growing and making their [medical school] applications really strong.” Attend any student-led event on campus and you’re more than likely to find an Honors student behind the scenes. Just as Honors students study in a wide range of academic fields, they also serve in leadership roles ranging from student government to peer mentor programs. 5 Barnette and Michael Popich, the Ethics Bowl team’s coaches, helped him develop leadership skills when he and another Honors student were the only returning members. Hasanbegovic says the responsibility of being a student leader is rewarding because “when things go well, that’s great; you know you helped do something great.” Emma Metos, a third-year student at Westminster, is the managing editor of Ellipsis, a consultant in the Westminster Writing Center, the vice president of Westminster Girl Up, the vice president of Westminster Slam, and a logistics officer for Democracy Matters. Though she fills many roles, Metos says her most important leadership position is as a Teaching Fellow for the Utah Humanities Clemente course because she is passionate about working with high school students. Metos aspires to be a teacher in a secondary institution and says she appreciates the opportunities for mentorship her leadership positions have provided her. Metos says she sees immediate benefits from student leadership. “Student leadership has helped me get every bit out of those tuition dollars that I can,” she says. “It feels like I am getting the most of my college experience and I am really enjoying myself.” To manage the stress of her leadership roles, Metos suggests keeping extensive to-do lists and having a designated “no email and no homework day” to help balance school and clubs with a social and personal life. Selina Foster works next to her pup in the Westminster Writing Center. Photo Courtesy of Calen Smith Selina Foster, a fourth-year student in the Honors program, is the assistant director of the Writing Center, a trip leader for the Outdoor Program, president of the Westminster math society (Lemma), and an Honors peer mentor. She credits Willy Palomo, a Westminster alumnus and her Honors peer mentor, as a major influence on her desire to work in the Writing Center, as well as Honors director Richard Badenhausen, who encouraged her to take Theory & Teaching of Writing from Chris LeCluyse. As president of Lemma, Foster organized an outreach program with Promise South Salt Lake’s STEM Center to expose younger students to the STEM fields. As she concludes her time on campus as a student leader, Foster notes that she “like[s] to do a lot of things across a lot of disciplines,” and says the most rewarding thing of being a student leader is getting to “see other people getting excited about what you do and asking about it and then wanting to be a part of it.” Grayson Massey is a second-year student involved in the Presidential Ambassador program, an ASW Senator, and the president of the Westminster College Republicans club. Off campus, he is the vice chairman for the Utah Young Republicans, vice president for the State College Republicans, and state secretary for PBL (Phi Beta Lambda), a collegiate arm of FBLA (Future Business Leaders of America). Massey says one of his goals when he came to Westminster was to be very involved, and he says he has received support from his parents, professors, peers, and Badenhausen. This support has helped Massey pursue his passion for politics. “I [lead] because I genuinely enjoy people,” he says. “I like getting to know people, and I am really a policy guy at heart.” Though he says he knows being involved in multiple leadership positions can be tiring and difficult to balance, Massey says he enjoys being involved with organizations that are important to him. Gano Hasanbegovic, a third-year student in the Honors program, serves as the communication officer for Westminster’s Psychology Club and is a member of the Ethics Bowl Team. Hasanbegovic says he began his on-campus leadership through GriffinQuest, where he learned “what it means to be a leader and different kinds of leadership.” He then decided to become a member and leader of the Psychology Club following his interest of majoring in psychology. In addition to leading through GriffinQuest and the Psychology Club, Hasanbegovic says Honors professors Kara Emma Metos in her role as the Teaching Fellow for the Utah Humanities Clemente Course. Photo Courtesy of Jean Cheney Grayson Massey discusses school policy with Andrey Chen (not pictured). Photo Courtesy of Calen Smith 6 Aaron Smith records observational data in Meldrum as part of his role in ACS. Photo Courtesy of Calen Smith Angie Mock decorates her residence hall for students as part of her role as Resident Advisor. Photo Courtesy of Calen Smith Second-year Angie Mock is a resident advisor, a member of the mock trial team and the vice president of Democracy Matters, a role in which she promotes non-partisan political engagement. She says her interest in student leadership stems from her enthusiasm for meeting and getting to know new people on campus. “I love to hear about what other people are doing and build relationships with them,” Mock says. “I like how anywhere I go on campus I can see people that I directly work with all the time.” Mock encourages students who want to become more involved on campus to seek out resources like Honors peer mentors or resident advisors who are likely to be in leadership positions themselves. She also encourages students to find people they enjoy working with and pursue leadership positions in areas they care about. Molinari credits Honors professor Kara Barnette with helping her grow as a student leader and reinforcing her passions for feminism and activism. Her advice to other student leaders for maintaining school/life balance is to utilize the available resources on campus, such as office hours with faculty, the Writing Center, and the Counseling Center. Aaron Smith pursued multiple leadership roles as a first-year student. In addition to holding leadership positions in the ACS and the Republican Club, Smith is the founder and president of the Strength Club. Like Fasiang, Smith credits his involvement with the ACS to Robyn Hyde, who advised him to join ACS even before he came to Westminster if he was serious about pursuing pre-med. He says he decided to start the Strength Club because, unlike other schools he considered attending, Westminster did not have any sort of weightlifting or Cross-Fit club. Smith says the most rewarding part about being a student leader is that he feels “the work I put in is actually something I can get out of it.” As a first-year, Katy Molinari led the education section of Students for Choice, going to on-campus dorms and apartments and teaching students about bystander intervention and sex education. She says she became involved because she is passionate about reproductive justice and finds that educating others is a very rewarding experience. “I love the fact that I get to teach about something that’s so important and that’s not taught about enough. I feel like what I do is making a difference and I love that I can give students experiences that I never had.” Honors students represent Westminster in a variety of leadership positions both on and off campus. Across expansive and diverse interests and leadership styles, Honors student leaders collectively encourage other students to get involved in their own forms of leadership. Massey’s advice, for example, is to “find what you’re passionate about and interested in and then reach out. I’ve never had anybody turn me away because I was interested in something.” Katy Molinari leads the education section for Students for Choice. Photo Courtesy of Calen Smith 7 Student Profile: Global Scholar Debbie Samaniego B Y: S T E P H A N I E H E L D Debbie Samaniego, a senior political science major, was one of approximately 900 applicants from around the country this year to win one of forty prestigious Marshall Scholarships, which will allow her to attend her choice of graduate programs in the United Kingdom. For Samaniego, this represents many firsts—she was the first member of her family to pursue higher education and is the first Westminster College student to receive this full-ride scholarship. Samaniego said she worked on her application essays intensively for two months, going through two revisions per week with her advisor, Jo Hinsdale, on essay topics ranging from diversity and leadership to community engagement. After the first round of cuts, Samaniego flew to California for a final interview. The next day, she received a call with the good news. “I just started crying, actually; it was pretty funny,” Samaniego said. “I’ve never had an experience that just, like, brought me to tears.” Samaniego said the Marshall Scholarship was her “reach-for-thestars” scholarship. And now that she has it, she said she hopes her accomplishments will inspire others to push the boundaries of what they believe they’re capable of. “I want to show people that we could do it,” Samaniego said. “Not that I could do it, but that anyone like me could do it—any student who’s [a] low-income, first generation [student] who has a lot of other struggles to go through.” Photo Courtesy of Felix Mantz Samaniego said her desire to uplift students from her same background drives her forward. For the last three years, she has volunteered with the Clemente program, which is co-sponsored by Westminster’s Honors program and helps encourage underserved students from East High School to pursue higher education. Samaniego advised her fellow Honors students to find leadership roles related to their passions in life. “I try to be a mentor or guide students that have the same questions that I had and just simply [try] to make it easier for them because I know it wasn’t easy for me,” Samaniego said. “I really wanted to work with the youth around Salt Lake City—people who came from a similar background as me—because that’s where I wanted to help.” Professor Profile: Equality Advocate Jo Hinsdale B Y: S C O U T I N V I E Mary Jo Hinsdale, director of the McNair Scholars Program and an adjunct professor in the Science, Power, & Diversity Honors seminar, has made a real-world impact at Westminster through her research questioning dominant narratives in academia, bringing issues of diversity into the classroom, and preparing students from underrepresented groups for graduate school and beyond. Her work in diversity hasn’t gone unnoticed. Hinsdale was recently one of three recipients who received the Unsung Hero award,
Connective tissue responses to calcium hydroxide-based root canal medicaments
No full textAim: The objective of the present study was to evaluate the tissue inflammatory response induced by calcium hydroxide pastes, with or without paramonochlorophenol and camphor. Methodology: Isogenic BALB/c mice were inoculated into the subcutaneous tissue with either 0.1 mL of a suspension of Calen, Calen with camphorated paramonochlorophenol, Calen with paramonochlorophenol, Calasept paste or phosphate-buffered saline (control). After 6, 12 and 24 h and 2, 3, 5, 7 and 15 days, three animals in each group were sacrificed and the excised lesions processed for histopathological evaluation of the inflammatory response. Events monitored and graded included the assessment of vascular congestion, oedema, haemorrhage, inflammatory infiltrate, necrosis and tissue repair. Results: The pastes induced an inflammatory response at every observation period, although the intensity, duration and extension of inflammation varied. Calen paste always produced an initial short-term inflammatory response whilst the other pastes produced extended reactions. All pastes allowed repair to take place by the end of the experimental period, although the speed of this process varied between the materials. Calen presented the best biocompatibility; the phenolic compound caused greater tissue response, which was even more severe in the absence of camphor. Calasept paste was damaging and the repair process slower. Conclusions: All calcium hydroxide formulations caused an inflammatory response. The severity and longevity of the responses varied between pastes as a result of the various antiseptic agents. Although irritating, repair was apparent with all formulations
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Water Recovery from Bioreactor Mixed Liquors Using Forward Osmosis with Polyelectrolyte Draw Solutions
No full textThe objective of this research was to test the feasibility of using forward osmosis (FO) with polyelectrolyte draw solutions to recover water from bioreactor mixed liquors. When combined with an Anaerobic Osmotic Membrane Bioreactor (AnOMBR), such a system could process fecal and food waste from astronauts aboard the International Space Station (ISS) and reclaim important nutrients and water. This project focused on measuring the obtainable water recovery rates from bioreactor effluent, and the identifying challenges associated with the operation.
AnOMBRs feature several advantages over aerobic bioreactors, and non-osmotic anaerobic membrane bioreactors (AnMBR). Anaerobic bioreactors avoid the significant energy costs of aerobic bioreactors. Conventional AnMBRs use microfiltration or ultrafiltration with an applied pressure. AnOMBRs use FO membranes that do not allow low molecular weight organics to pass, and do not require an applied pressure. AnOMBRs may be an option for water and nutrient recovery in space if they can attain high water flux and reverse solute flux selectivity (RSFS), which quantifies the volume of permeated water per gram of draw solute that has diffused from the draw solution into the bioreactor. To obtain a high RSFS, poly(acrylic acid) and poly(acrylic acid-co-maleic acid) were evaluated as draw solutes. The large size of the polymer and the high osmotic pressure they can provide make them highly advantageous.
Water flux was measured in a direct flow system using wastewater from a municipal wastewater treatment plant and draw solutions prepared with two polyelectrolytes at different concentrations. The direct flow tests displayed a high initial flux (\u3e10 L/m2/h) that decreased rapidly as solids accumulated on the feed side of the membrane. A test with deionized water as the feed revealed an exceedingly small mass of polyelectrolyte crossover from the draw solution to the feed; thus, RSFS was 80, which was higher than the target value of 20 for viable operation. Crossflow filtration experiments demonstrated that steady state flux above 2 L/m2/h could be maintained for 70 h following an initial flux decline due to formation of a foulant cake layer. This study established that FO could be feasible for regenerative water purification from bioreactor digesters. By utilizing a polyelectrolyte draw solute with exceedingly high RSFS, we expect to overcome the need for draw solute replenishment. This would be a major step towards sustainable operation in long-duration space missions lasting 30 months or more
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