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2,957 results on '"Lenzer"'

1. Implementation of self-directed learning within clinical clerkships

Author

Röcker, Navina, Lottspeich, Christian, Braun, Leah T., Lenzer, Benedikt, Frey, Jessica, Fischer, Martin R., and Schmidmaier, Ralf

Subjects
curricular development, clinical clerkship, learning objective, self-directed learning, undergraduate medical education, Special aspects of education, LC8-6691, Medicine
Abstract

Background: The main aim of medical curricula is to prepare students for the first day at the work place. While teaching clinical competence is pivotal, clinical clerkships are often the last chance to close knowledge gaps with the help of clinical teachers. Self-directed learning is a dynamic field for research within medical education, though its curricular implementation is rare. This study focuses on the needs assessment of clinical clerkships using the concept of self-directed learning. Methods: The study comprised an educational experience at the Ludwig-Maximilians Universität (LMU) Munich. Medical students (n=1446, 59% female) in their second clinical year were instructed to specify learning objectives (LOs) by Doran`s SMART criteria and to gauge the probability of their fulfilment prior to the mandatory clerkship. In a second questionnaire one week later, the students rated the actual subjective fulfilment of the LOs. Data was coded with regards to the German National Catalogue of Competence-Based Learning Objectives for Undergraduate Medical Education (NKLM) and investigated qualitatively. Factors that determine goal achievement were collected and coded binary (barrier vs. enabler). Univariate analysis was used when appropriate. Results: The acquisition of “clinically practical abilities” (29%), “diagnostic methods” (21%) and “professional communication” (13%) were the LOs mentioned most. Throughout the week, subjective fulfilment diminished. Rich (vs. poor) availability to “practical exercise” (31%), “engagement of the physicians and other medical staff” (27%) and “personal initiative” (23%) resulted in higher subjective fulfilment. Conclusions: The self-chosen LOs reflect the needs of students for which the clinical teacher should be prepared. Considering these findings, it seems possible to close practical training gaps. We support the consideration of establishing curricular anchored self-directed learning in clinical clerkships. Further empirical studies would be beneficial in revealing its positive effects on the learning progress.

Published
2021
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2. Clinical Case Discussions – a novel, supervised peer-teaching format to promote clinical reasoning in medical students

Author

Koenemann, Nora, Lenzer, Benedikt, Zottmann, Jan M., Fischer, Martin R., and Weidenbusch, Marc

Subjects
case-based learning, clinical reasoning, peer teaching, curriculum development, undergraduate medical education, Special aspects of education, LC8-6691, Medicine
Abstract

Background: Clinical reasoning (CR) is a clinical core competence for medical students to acquire. While the necessity for CR teaching has been recognized since the early 20 century, to this day no consensus on how to best educate students in CR exists. Hence, few universities have incorporated dedicated CR teaching formats into their medical curriculum. We propose a novel case-based, peer-taught and physician-supervised collaborative learning format, dubbed “Clinical Case Discussions” (CCDs) to foster CR in medical students.Project description: We present the curricular concept of CCDs and its development according to a six-step approach (problem identification and general needs assessment; targeted needs assessment; goals and objectives; educational strategies; implementation; evaluation and feedback). Our goal is to strengthen the physician roles (CanMEDS/NKLM) and CR competence of medical students. CCDs are offered at our institution as an elective course and students work on real-life, complex medical cases through a structured approach. Over the course of five years we evaluated various aspects of the course and trained student teachers to optimize our course concept according to the feedback of our participants. We also obtained intro and exit self-assessments of CR competence using an established CR questionnaire.Results: We found an unmet need for CR teaching, as medical students in their clinical years view CR as highly important for later practice, but only 50% have ever heard of CR within the curriculum. Acceptance of CCDs was consistently high with over 85% of participants strongly agreeing that they would re-participate in the course and recommend it to a friend. Additionally, we observed significant improvements in CR self-assessments of participants.Conclusion: CCDs are a feasible teaching format to improve students’ CR competence, have a high acceptance and involve students in medical education through peer-teaching.

Published
2020
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4. How case representations of medical students change during case processing – Results of a qualitative study

Author

Braun, Leah Theresa, Lenzer, Benedikt, Kiesewetter, Jan, Fischer, Martin R., and Schmidmaier, Ralf

Subjects
diagnostic competence, clinical reasoning, undergraduate medical education, Special aspects of education, LC8-6691, Medicine
Abstract

Objective: Representations are mental summaries of a clinical case and help in understanding a clinical problem. However, it is still largely unknown which clinical information medical students include in their case representations. In this study, therefore, the structure and quality of students’ case representations were examined to better understand the diagnostic process and its relationship to diagnostic accuracy. What information do medical students include in their representations and is there an association between this information and the diagnostic accuracy?Method: 43 medical students in the fourth and fifth clinical year worked on four clinical cases. During the diagnostic process, they were asked three times per case to write a case representation. 516 representations were qualitatively evaluated using a content-based coding scheme. An analysis was made of the nature and composition of the clinical information. In addition, the association between the general representation structure and the correct case solution was examined.Results: At the beginning, students include most of the clinical information in their representation (66%), but as the case progresses, they begin to select the information offered (2nd representation 42%, 3rd representation 38%). The length of the representation (number of words) does not correlate with the correct case solution (r=-0.08-0.31). The representations do not depend on the case difficulty but have a significant individual component: the representations written by a student are formally very similar in all four cases(r=0.60-0.86).Conclusion: Medical students can select the relevant clinical information and include it in their case representations. Lack of representation does not seem to be a reason for misdiagnosis; Students’ deficits in diagnosis are more likely due to knowledge gaps.

Published
2018
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5. Advancing clinical reasoning in virtual patients – development and application of a conceptual framework

Author

Hege, Inga, Kononowicz, Andrzej A., Berman, Norman B., Lenzer, Benedikt, and Kiesewetter, Jan

Subjects
Virtual Patients, Clinical Reasoning, Qualitative Research, Healthcare Education, Special aspects of education, LC8-6691, Medicine
Abstract

Background: Clinical reasoning is a complex skill students have to acquire during their education. For educators it is difficult to explain their reasoning to students, because it is partly an automatic and unconscious process. Virtual Patients (VPs) are used to support the acquisition of clinical reasoning skills in healthcare education. However, until now it remains unclear which features or settings of VPs optimally foster clinical reasoning. Therefore, our aims were to identify key concepts of the clinical reasoning process in a qualitative approach and draw conclusions on how each concept can be enhanced to advance the learning of clinical reasoning with virtual patients. Methods: We chose a grounded theory approach to identify key categories and concepts of learning clinical reasoning and develop a framework. Throughout this process, the emerging codes were discussed with a panel of interdisciplinary experts. In a second step we applied the framework to virtual patients. Results: Based on the data we identified the core category as the "multifactorial nature of learning clinical reasoning". This category is reflected in the following five main categories: Psychological Theories, Patient-centeredness, Context, Learner-centeredness, and Teaching/Assessment. Each category encompasses between four and six related concepts. Conclusions: With our approach we were able to elaborate how key categories and concepts of clinical reasoning can be applied to virtual patients. This includes aspects such as allowing learners to access a large number of VPs with adaptable levels of complexity and feedback or emphasizing dual processing, errors, and uncertainty.

Published
2018
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8. Annealing temperature-dependent induced supramolecular chiroptical response of copolymer thin films studied by pump-modulated transient circular dichroism spectroscopy

Author

Domenic Gust, Mirko Scholz, Vivien Schumacher, Jean-Christophe Mulatier, Delphine Pitrat, Laure Guy, Kawon Oum, and Thomas Lenzer

Subjects
Medicine, Science
Abstract

Abstract Copolymer thin films showing induced supramolecular chirality are of considerable interest for optoelectronic applications such as organic light-emitting diodes. Here, we introduce a new helicene-like chiral additive with two octyloxy substituents which displays excellent chiral induction properties in an achiral polyfluorene copolymer, leading to a circular dichroism (CD) response of up to 10,000 mdeg. This chiral inducer also displays very good thermal stability, which enables us to perform an extended study on the induced chiroptical properties of the cholesteric copolymer thin films annealed at different temperatures in the range 140–260 °C. Starting from about 180 °C, a distinct change in the morphology of the CD-active film is observed by CD microscopy, from micrometre-size granular to extended CD-active regions, where the latter ones display skewed distributions of the dissymmetry parameter g abs. Broadband Müller matrix spectroscopy finds a pronounced CD and circular birefringence (CB) response and only weak linear dichroism (LD, LD’) and linear birefringence (LB, LB’). Ultrafast transient CD spectroscopy with randomly polarised excitation reveals a clean mirror-image-type transient response, which shows a second-order decay of the S1 population due to singlet–singlet annihilation processes.

Published
2024
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11. Excited-State Dynamics of Carbazole and tert-Butyl-Carbazole in Thin Films

Author

Konstantin Moritz Knötig, Domenic Gust, Kawon Oum, and Thomas Lenzer

Subjects
carbazole, thin films, ultrafast laser spectroscopy, singlet–singlet annihilation, picosecond ultrasonics, Chemistry, QD1-999
Abstract

Thin films of carbazole (Cz) derivatives are frequently used in organic electronics, such as organic light-emitting diodes (OLEDs). Because of the proximity of the Cz units, the excited-state relaxation in such films is complicated, as intermolecular pathways, such as singlet–singlet annihilation (SSA), kinetically compete with the emission. Here, we provide an investigation of two benchmark systems employing neat carbazole and 3,6-di-tert-butylcarbazole (t-Bu-Cz) films and also their thin film blends with poly(methyl methacrylate) (PMMA). These are investigated by a combination of atomic force microscopy (AFM), femtosecond and nanosecond transient absorption spectroscopy (fs-TA and ns-TA) and time-resolved fluorescence. Excitonic J-aggregate-type features are observed in the steady-state absorption and emission spectra of the neat films. The S1 state shows a broad excited-state absorption (ESA) spanning the entire UV–Vis–NIR range. At high S1 exciton number densities of about 4 × 1018 cm−3, bimolecular diffusive S1–S1 annihilation is found to be the dominant SSA process in the neat films with a rate constant in the range of 1–2 × 10−8 cm3 s−1. SSA produces highly vibrationally excited molecules in the electronic ground state (S0*), which cool down slowly by heat transfer to the quartz substrate. The results provide relevant photophysical insight for a better microscopic understanding of carbazole relaxation in thin-film environments.

Published
2024
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12. Excited-State Dynamics of Carbazole and tert-Butyl-Carbazole in Organic Solvents

Author

Konstantin Moritz Knötig, Domenic Gust, Thomas Lenzer, and Kawon Oum

Subjects
carbazole, excited-state dynamics, deep-UV ultrafast laser spectroscopy, triplet formation, Chemistry, QD1-999
Abstract

Carbazole-based molecular units are ubiquitous in organic optoelectronic materials; however, the excited-state relaxation of these compounds is still underexplored. Here, we provide a detailed investigation of carbazole (Cz) and 3,6-di-tert-butylcarbazole (t-Bu-Cz) in organic solvents using femtosecond and nanosecond UV–Vis–NIR transient absorption spectroscopy, as well as time-resolved fluorescence experiments upon photoexcitation in the deep-UV range. The initially prepared Sx singlet state has a (sub-)picosecond lifetime and decays to the S1 state by internal conversion (IC). The S1 state exhibits absorption peaks at 350, 600 and 1100 nm and has a lifetime of 13–15 ns, which is weakly dependent on the solvent. Energy transfer from vibrationally hot S1 molecules (S1*) to the surrounding solvent molecules takes place with a time constant of 8–20 ps. The T1 triplet state is populated by intersystem crossing (ISC) from S1 with a typical quantum yield of 51–56% and shows a lifetime which is typically in the few microseconds regime. The S1 and T1 states of both carbazole compounds in solution are strongly quenched by O2. Two-photon excitation leads to the formation of a small amount of the respective radical cation. The influence of the tert-butyl substituents on the photophysics is relatively weak and mainly reflects itself in a small increase in the Stokes shift. The results provide important photophysical information for the interpretation of carbazole relaxation in more complex environments.

Published
2024
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14. How Learnweb Can Support Science Education Research on Climate Change in Social Media

Author

Upadhyaya, Apoorva, Pfeiffer, Catharina, Astappiev, Oleh, Marenzi, Ivana, Lenzer, Stefanie, Nehring, Andreas, Fisichella, Marco, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Temperini, Marco, editor, Scarano, Vittorio, editor, Marenzi, Ivana, editor, Kravcik, Milos, editor, Popescu, Elvira, editor, Lanzilotti, Rosa, editor, Gennari, Rosella, editor, De La Prieta, Fernando, editor, Di Mascio, Tania, editor, and Vittorini, Pierpaolo, editor

Published
2023
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19. Excited-State Dynamics of Bis(tetraethylammonium) Di-µ-bromo-dibromodicuprate(I) Thin Films

Author

Domenic Gust, Mirko Scholz, Kawon Oum, and Thomas Lenzer

Subjects
molecular salts, halocuprates, ultrafast laser spectroscopy, triplet emission, Organic chemistry, QD241-441
Abstract

Organic–inorganic halocuprates based on monovalent copper are promising luminescent compounds for optoelectronic applications; however, their relaxation processes in the excited electronic state are severely underexplored. In this contribution, we prepare thin films of bis(tetraethylammonium) di-µ-bromo-dibromodicuprate(I) [N(C2H5)4]2[Cu2Br4], abbreviated (TEA)2Cu2Br4, which features a “molecular salt” structure containing discrete [Cu2Br4]2− anions. This compound, which has an absorption peak at 283 nm, displays a blue, strongly Stokes-shifted emission with a peak at 467 nm. Transient photoluminescence (PL) experiments using broadband emission detection and time-correlated single-photon counting (TCSPC) both find an excited-state lifetime of 57 μs at 296 K. UV–Vis transient absorption experiments at 296 K covering time scales from femto- to microseconds provide evidence for the formation of the T1 state through intersystem crossing from S1 with a time constant of 184 ps. The triplet state subsequently decays to S0 predominantly by phosphorescence. In addition, the time constants for carrier–optical phonon scattering (1.8 ps) and acoustic phonon relaxation (8.3 ns and 465 ns) of (TEA)2Cu2Br4 are provided.

Published
2023
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21. How Do Students Become Experts? An In-Depth Study on the Development of Domain-Specific Awareness in a Materials Chemistry Course

Author

Lenzer, Stefanie, Smarsly, Bernd, and Graulich, Nicole

Abstract

The need to develop clean-energy storage systems, harvesting technologies, and new functional materials are but a few of the many contemporary challenges in the domain of science today. To address these challenges, problem solving has become a key skill of the 21st century. It is generally documented, however, that experts and students differ in terms of their problem-solving skills. Experts in a domain are fluent in the use of different resources to solve domain-specific problems, whereas students stumble when using formulas, devices, or measurement methods. In most cases, the students are not aware if and why the resources are appropriate to solve the given problem. To acquire expertise in a domain, it is necessary to become fluent in the domain-specific resources. This means being aware of various resources and how they can be used reflectively in problem solving. In this study, we investigated how students' awareness of various domain-specific resources developed within minimally guided, authentic research projects in an undergraduate materials chemistry course that focuses on crystal structures and its characterisation. By monitoring participants' problem solving through audio-diaries and in-depth qualitative interview data, we examined to what extent their awareness of domain-specific resources developed. We further characterised productive moments of failure and uncertainty during students' problem-solving processes that influenced their awareness. Thick descriptions of these moments facilitate understanding of how students' awareness develops in a minimally guided, authentic learning environment and how students can become fluent in a given domain.

Published
2020
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29. Second asymptomatic carotid surgery trial (ACST-2): a randomised comparison of carotid artery stenting versus carotid endarterectomy

Author

Halliday, Alison, Bulbulia, Richard, Bonati, Leo H, Peto, Richard, Pan, Hongchao, Potter, John, Henning Eckstein, Hans, Farrell, Barbara, Flather, Marcus, Mansfield, Averil, Mihaylova, Boby, Rahimi, Kazim, Simpson, David, Thomas, Dafydd, Sandercock, Peter, Gray, Richard, Molyneux, Andrew, Shearman, Cliff P, Rothwell, Peter, Belli, Anna, Herrington, Will, Judge, Parminder, Leopold, Peter, Mafham, Marion, Gough, Michael, Cao, Piergiorgio, MacDonald, Sumaira, Bari, Vasha, Berry, Clive, Bradshaw, S, Brudlo, Wojciech, Clarke, Alison, Chester, Johanna, Cox, Robin, Cradduck-Bamford, Andrea, Fathers, Susan, Gaba, Kamran, Gray, Mo, Hayter, Elizabeth, Holliday, Constance, Kurien, Rijo, Lay, Michael, le Conte, Steffi, McManus, Jessica, Madgwick, Zahra, Morris, Dylan, Munday, Andrew, Pickworth, Sandra, Ostasz, Wiktor, Poorthuis, Michiel, Richards, Sue, Teixeira, Louisa, Tochlin, Sergey, Tully, Lynda, Wallis, Carol, Willet, Monique, Young, Alan, Casana, Renato, Malloggi, Chiara, Odero Jr, Andrea, Silani, Vincenzo, Parati, Gianfranco, Malchiodi, Giuseppe, Malferrari, Giovanni, Strozzi, Francesco, Tusini, Nicola, Vecchiati, Enrico, Coppi, Gioacchino, Lauricella, Antonio, Moratto, Roberto, Silingardi, Roberto, Veronesi, Jessica, Zini, Andrea, Ferrero, Emanuele, Ferri, Michelangelo, Gaggiano, Andrea, Labate, Carmelo, Nessi, Franco, Psacharopulo, Daniele, Viazzo, Andrea, Malacrida, Giovanni, Mazzaccaro, Daniela, Meola, Giovanni, Modafferi, Alfredo, Nano, Giovanni, Occhiuto, Maria Teresa, Righini, Paolo, Stegher, Silvia, Chiarandini, Stefano, Griselli, Filippo, Lepidi, Sandro, Pozzi Mucelli, Fabio, Naccarato, Marcello, D'Oria, Mario, Ziani, Barbara, Stella, Andrea, Dieng, Mortalla, Faggioli, Gianluca, Gargiulo, Mauro, Palermo, Sergio, Pini, Rodolfo, Puddu, Giovanni Maria, Vacirca, Andrea, Angiletta, Domenico, Desantis, Claudio, Marinazzo, Davide, Mastrangelo, Giovanni, Regina, Guido, Pulli, Raffaele, Bianchi, Paolo, Cireni, Lea, Coppi, Elisabetta, Pizzirusso, Rocco, Scalise, Filippo, Sorropago, Giovanni, Tolva, Valerio, Caso, Valeria, Cieri, Enrico, DeRango, Paola, Farchioni, Luca, Isernia, Giacomo, Lenti, Massimo, Parlani, Gian Battista, Pupo, Guglielmo, Pula, Grazia, Simonte, Gioele, Verzini, Fabio, Carimati, Federico, Delodovici, Maria Luisa, Fontana, Federico, Piffaretti, Gabriele, Tozzi, Matteo, Civilini, Efrem, Poletto, Giorgio, Reimers, Bernhard, Praquin, Barbara, Ronchey, Sonia, Capoccia, Laura, Mansour, Wassim, Sbarigia, Enrico, Speziale, Francesco, Sirignano, Pasqualino, Toni, Danilo, Galeotti, Roberto, Gasbarro, Vincenzo, Mascoli, Francesco, Rocca, Tiberio, Tsolaki, Elpiniki, Bernardini, Giulia, DeMarco, Ester, Giaquinta, Alessia, Patti, Francesco, Veroux, Massimiliano, Veroux, Pierfrancesco, Virgilio, Carla, Mangialardi, Nicola, Orrico, Matteo, Di Lazzaro, Vincenzo, Montelione, Nunzio, Spinelli, Francesco, Stilo, Francesco, Cernetti, Carlo, Irsara, Sandro, Maccarrone, Giuseppe, Tonello, Diego, Visonà, Adriana, Zalunardo, Beniamino, Chisci, Emiliano, Michelagnoli, Stefano, Troisi, Nicola, Masato, Maela, Dei Negri, Massimo, Pacchioni, Andrea, Saccà, Salvatore, Amatucci, Giovanni, Cannizzaro, Alfredo, Accrocca, Federico, Ambrogi, Cesare, Barbazza, Renzo, Marcucci, Giustino, Siani, Andrea, Bajardi, Guido, Savettieri, Giovanni, Argentieri, Angelo, Corbetta, Riccardo, Odero, Attilio, Quaretti, Pietro, Thyrion, Federico Z, Cappelli, Alessandro, Benevento, Domenico, De Donato, Gianmarco, Mele, Maria Agnese, Palasciano, Giancarlo, Pieragalli, Daniela, Rossi, Alessandro, Setacci, Carlo, Setacci, Francesco, Palombo, Domenico, Perfumo, Maria Cecilia, Martelli, Edoardo, Paolucci, Aldo, Trimarchi, Santi, Grassi, Viviana, Grimaldi, Luigi, La Rosa, Giuliana, Mirabella, Domenico, Scialabba, Matteo, Sichel, Leonildo, D'Angelo, Costantino L, Fadda, Gian Franco, Kasemi, Holta, Marino, Mario, Burzotta, Francesco, Codispoti, Francesco Alberto, Ferrante, Angela, Tinelli, Giovanni, Tshomba, Yamume, Vincenzoni, Claudio, Amis, Deborah, Anderson, Dawn, Catterson, Martin, Clarke, Mike, Davis, Michelle, Dixit, Anand, Dyker, Alexander, Ford, Gary, Jackson, Ralph, Kappadath, Sreevalsan, Lambert, David, Lees, Tim, Louw, Stephen, McCaslin, James, Parr, Noala, Robson, Rebecca, Stansby, Gerard, Wales, Lucy, Wealleans, Vera, Wilson, Lesley, Wyatt, Michael, Baht, Hardeep, Balogun, Ibrahim, Burger, Ilse, Cosier, Tracy, Cowie, Linda, Gunathilagan, Gunaratnam, Hargroves, David, Insall, Robert, Jones, Sally, Rudenko, Hannah, Schumacher, Natasha, Senaratne, Jawaharlal, Thomas, George, Thomson, Audrey, Webb, Tom, Brown, Ellen, Esisi, Bernard, Mehrzad, Ali, MacSweeney, Shane, McConachie, Norman, Southam, Alison, Sunman, Wayne, Abdul-Hamiq, Ahmed, Bryce, Jenny, Chetter, Ian, Ettles, Duncan, Lakshminarayan, Raghuram, Mitchelson, Kim, Rhymes, Christopher, Robinson, Graham, Scott, Paul, Vickers, Alison, Ashleigh, Ray, Butterfield, Stephen, Gamble, Ed, Ghosh, Jonathan, McCollum, Charles N, Welch, Mark, Welsh, Sarah, Wolowczyk, Leszek, Donnelly, Mary, D'Souza, Stephen, Egun, Anselm A, Gregary, Bindu, Joseph, Thomas, Kelly, Christine, Punekar, Shuja, Rahi, M Asad, Raj, Sonia, Seriki, Dare, Thomson, George, Brown, James, Durairajan, Ragunath, Grunwald, Iris, Guyler, Paul, Harman, Paula, Jakeways, Matthew, Khuoge, Christopher, Kundu, Ashish, Loganathan, Thayalini, Menon, Nisha, Prabakaran, Raji O, Sinha, Devesh, Thompson, Vicky, Tysoe, Sharon, Briley, Dennis, Darby, Chris, Hands, Linda, Howard, Dominic, Kuker, Wilhelm, Schulz, Ursula, Teal, Rachel, Barer, David, Brown, Andrew, Crawford, Susan, Dunlop, Paul, Krishnamurthy, Ramesh, Majmudar, Nikhil, Mitchell, Duncan, Myint, Min P, O'Brien, Richard, O'Connell, Janice, Sattar, Naweed, Vetrivel, Shanmugam, Beard, Jonathan, Cleveland, Trevor, Gaines, Peter, Humphreys, John, Jenkins, Alison, King, Craig, Kusuma, Daniel, Lindert, Ralph, Lonsdale, Robbie, Nair, Raj, Nawaz, Shah, Okhuoya, Faith, Turner, Douglas, Venables, Graham, Dorman, Paul, Hughes, Andrea, Jones, Deborah, Mendelow, David, Rodgers, Helen, Raudoniitis, Aidas, Enevoldson, Peter, Nahser, Hans, O'Brien, Imelda, Torella, Francesco, Watling, Dave, White, Richard, Brown, Pauline, Dutta, Dipankar, Emerson, Lorraine, Hilltout, Paula, Kulkarni, Sachin, Morrison, Jackie, Poskitt, Keith, Slim, Fiona, Smith, Sarah, Tyler, Amanda, Waldron, Joanne, Whyman, Mark, Bajoriene, Milda, Baker, Lucy, Colston, Amanda, Eliot-Jones, Bekky, Gramizadeh, Gita, Lewis-Clarke, Catherine, McCafferty, Laura, Oliver, Deborah, Palmer, Debbie, Patil, Abhijeet, Pegler, Suzannah, Ramadurai, Gopi, Roberts, Aisling, Sargent, Tracey, Siddegowda, Shivaprasad, Singh-Ranger, Ravi, Williams, Akintunde, Williams, Lucy, Windebank, Steve, Zuromskis, Tadas, Alwis, Lanka, Angus, Jane, Asokanathan, Asaipillai, Fornolles, Caroline, Hardy, Diana, Hunte, Sophy, Justin, Frances, Phiri, Duke, Mitabouana-Kibou, Marie, Sekaran, Lakshmanan, Sethuraman, Sakthivel, Tate, Margaret L, Akyea-Mensah, Joyce, Ball, Stephen, Chrisopoulou, Angela, Keene, Elizabeth, Phair, Alison, Rogers, Steven, Smyth, John V, Bicknell, Colin, Chataway, Jeremy, Cheshire, Nicholas, Clifton, Andrew, Eley, Caroline, Gibbs, Richard, Hamady, Mohammad, Hazel, Beth, James, Alex, Jenkins, Michael, Khanom, Nyma, Lacey, Austin, Mireskandari, Maz, O'Reilly, Joanna, Pereira, Antony, Sachs, Tina, Wolfe, John, Davey, Philip, Rogers, Gill, Smith, Gemma, Tervit, Gareth, Nichol, Ian, Parry, Andrew, Young, Gavin, Ashley, Simon, Barwell, James, Dix, Francis, Nor, Azlisham M, Parry, Chris, Birt, Angela, Davies, Paul, George, Jim, Graham, Anne, Jonker, Leon, Kelsall, Nicci, Potts, Caroline, Wilson, Toni, Crinnion, Jamie, Cuenoud, Larissa, Aleksic, Nikola, Babic, Srdan, Ilijevski, Nenad, Radak, Đorde, Sagic, Dragan, Tanaskovic, Slobodan, Colic, Momcilo, Cvetic, Vladimir, Davidovic, Lazar, Jovanovic, Dejana R, Koncar, Igor, Mutavdžic, Perica, Sladojevic, Miloš, Tomic, Ivan, Debus, Eike S, Grzyska, Ulrich, Otto, Dagmar, Thomalla, Götz, Barlinn, Jessica, Gerber, Johannes, Haase, Kathrin, Hartmann, Christian, Ludwig, Stefan, Pütz, Volker, Reeps, Christian, Schmidt, Christine, Weiss, Norbert, Werth, Sebastian, Winzer, Simon, Gemper, Janine, Günther, Albrecht, Heiling, Bianka, Jochmann, Elisabeth, Karvouniari, Panagiota, Klingner, Carsten, Mayer, Thomas, Schubert, Julia, Schulze-Hartung, Friederike, Zanow, Jürgen, Bausback, Yvonne, Borger, Franka, Botsios, Spiridon, Branzan, Daniela, Bräunlich, Sven, Hölzer, Henryk, Lenzer, Janin, Piorkowski, Christopher, Richter, Nadine, Schuster, Johannes, Scheinert, Dierk, Schmidt, Andrej, Staab, Holger, Ulrich, Matthias, Werner, Martin, Berger, Hermann, Biró, Gábor, Eckstein, Hans-Henning, Kallmayer, Michael, Kreiser, Kornelia, Zimmermann, Alexander, Berekoven, Bärbel, Frerker, Klaus, Gordon, Vera, Torsello, Giovanni, Arnold, Sebastian, Dienel, Cora, Storck, Martin, Biermaier, Bernhard, Gissler, Hans Martin, Klötzsch, Christof, Pfeiffer, Tomas, Schneider, Ralph, Söhl, Leander, Wennrich, Michael, Alonso, Angelika, Keese, Michael, Groden, Christoph, Cöster, Andreas, Engelhardt, Andreas, Ratusinski, Christoph-Maria, Berg, Bengt, Delle, Martin, Formgren, Johan, Gillgren, Peter, Jarl, Lotta, Kall, Torbjörn B, Konrad, Peter, Nyman, Niklas, Skiöldebrand, Claes, Steuer, Johnny, Takolander, Rabbe, Malmstedt, Jonas, Acosta, Stefan, Björses, Katarina, Brandt, Kerstin, Dias, Nuno, Gottsäter, Anders, Holst, Jan, Kristmundsson, Thorarinn, Kühme, Tobias, Kölbel, Tilo, Lindblad, Bengt, Lindh, Mats, Malina, Martin, Ohrlander, Tomas, Resch, Tim, Rönnle, Viola, Sonesson, Björn, Warvsten, Margareta, Zdanowski, Zbigniew, Campbell, Erik, Kjellin, Per, Lindgren, Hans, Nyberg, Johan, Petersen, Björn, Plate, Gunnar, Pärsson, Håkan, Qvarfordt, Peter, Ignatenko, Pavel, Karpenko, Andrey, Starodubtsev, Vladimir, Chernyavsky, Mikhail A, Golovkova, Maria S, Komakha, Boris B, Zherdev, Nikolay N, Belyasnik, Andrey, Chechulov, Pavel, Kandyba, Dmitry, Stepanishchev, Igor, Csobay-Novák, Csaba, Dósa, Edit, Entz, László, Nemes, Balázs, Szeberin, Zoltán, Barzó, Pál, Bodosi, Mihaly, Fákó, Eniko, Fülöp, Béla, Németh, Tamás, Pazdernyik, Szilárd, Skoba, Krisztina, Vörös, Erika, Chatzinikou, Eleni, Giannoukas, Athanasios, Karathanos, Christos, Koutsias, Stylianos, Kouvelos, Georgios, Matsagkas, Miltiadis, Ralli, Styliani, Rountas, Christos, Rousas, Nikolaos, Spanos, Konstantinos, Brountzos, Elias, Kakisis, John D, Lazaris, Andreas, Moulakakis, Konstantinos G, Stefanis, Leonidas, Tsivgoulis, Georgios, Vasdekis, Spyros, Antonopoulos, Constantine N, Bellenis, Ion, Maras, Dimitrios, Polydorou, Antonios, Polydorou, Victoria, Tavernarakis, Antonios, Ioannou, Nikolaos, Terzoudi, Maria, Lazarides, Miltos, Mantatzis, Michalis, Vadikolias, Kostas, Dzieciuchowicz, Lukasz, Gabriel, Marcin, Krasinski, Zbigniew, Oszkinis, Grzegorz, Pukacki, Fryderyk, Slowinski, Maciej, Stanišic, Michal-Goran, Staniszewski, Ryszard, Tomczak, Jolanta, Zielinski, Maciej, Myrcha, Piotr, Rózanski, Dorota, Drelichowski, Stanislaw, Iwanowski, Wojciech, Koncewicz, Katarzyna, Bialek, Pawel, Biejat, Zbigniew, Czepel, Wojciech, Czlonkowska, Anna, Dowzenko, Anatol, Jedrzejewska, Julia, Kobayashi, Adam, Leszczynski, Jerzy, Malek, Andrzej, Polanski, Jerzy, Proczka, Robert, Skorski, Maciej, Szostek, Mieczyslaw, Andziak, Piotr, Dratwicki, Maciej, Gil, Robert, Nowicki, Miroslaw, Pniewski, Jaroslaw, Rzezak, Jaroslaw, Seweryniak, Piotr, Dabek, Pawel, Juszynski, Michal, Madycki, Grzegorz, Pacewski, Bartosz, Raciborski, Witold, Slowinski, Piotr, Staszkiewicz, Walerian, Bombic, Martin, Chlouba, Vladimír, Fiedler, Jirí, Hes, Karel, Koštál, Petr, Sova, Jindrich, Kríž, Zdenek, Prívara, Mojmír, Reif, Michal, Staffa, Robert, Vlachovský, Robert, Vojtíšek, Bohuslav, Hrbác, Tomáš, Kuliha, Martin, Procházka, Václav, Roubec, Martin, Školoudík, David, Netuka, David, Šteklácová, Anna, Beneš III, Vladimír, Buchvald, Pavel, Endrych, Ladislav, Šercl, Miroslav, Campos Jr, Walter, Casella, Ivan B, de Luccia, Nelson, Estenssoro, André E V, Presti, Calógero, Puech-Leão, Pedro, Neves, Celso R B, da Silva, Erasmo S, Sitrângulo Jr, Cid J, Monteiro, José A T, Tinone, Gisela, Bellini Dalio, Marcelo, Joviliano, Edwaldo E, Pontes Neto, Octávio M, Serra Ribeiro, Mauricio, Cras, Patrick, Hendriks, Jeroen M H, Hoppenbrouwers, Mieke, Lauwers, Patrick, Loos, Caroline, Yperzeele, Laetitia, Geenens, Mia, Hemelsoet, Dimitri, van Herzeele, Isabelle, Vermassen, Frank, Astarci, Parla, Hammer, Frank, Lacroix, Valérie, Peeters, André, Verhelst, Robert, Cirelli, Silvana, Dormal, Pol, Grimonprez, Annelies, Lambrecht, Bart, Lerut, Philipe, Thues, Eddy, De Koster, Guy, Desiron, Quentin, Maertens de Noordhout, Alain, Malmendier, Danielle, Massoz, Mireille, Saad, Georges, Bosiers, Marc, Callaert, Joren, Deloose, Koen, Blanco Cañibano, Estrella, García Fresnillo, Beatriz, Guerra Requena, Mercedes, Morata Barrado, Pilar C, Muela Méndez, Miguel, Yusta Izquierdo, Antonio, Aparici Robles, Fernando, Blanes Orti, Paula, García Dominguez, Luis, Martínez López, Rafael, Miralles Hernández, Manuel, Tembl Ferrairo, José I, Chamorro, Ángel, Macho, Juan, Obach, Víctor, Riambau, Vincent, San Román, Luis, Ahlhelm, Frank J, Blackham, Kristine, Engelter, Stefan, Eugster, Thomas, Gensicke, Henrik, Gürke, Lorenz, Lyrer, Philippe, Mariani, Luigi, Maurer, Marina, Mujagic, Edin, Müller, Mandy, Psychogios, Marios, Stierli, Peter, Stippich, Christoph, Traenka, Christopher, Wolff, Thomas, Wagner, Benjamin, Wiegert, Martina M, Clarke, Sandra, Diepers, Michael, Gröchenig, Ernst, Gruber, Philipp, Isaak, Andrej, Kahles, Timo, Marti, Regula, Nedeltchev, Krassen, Remonda, Luca, Tissira, Nadir, Valença Falcão, Martina, de Borst, Gert J, Lo, Rob H, Moll, Frans L, Toorop, Raechel, van der Worp, Bart H, Vonken, Evert J, Kappelle, Jaap L, Jahrome, Ommid, Vos, Floris, Schuiling, Wouter, van Overhagen, Hendrik, Keunen, Rudolf W M, Knippenberg, Bob, Wever, Jan J, Lardenoije, Jan W, Reijnen, Michel, Smeets, Luuk, van Sterkenburg, Steven, Fraedrich, Gustav, Gizewski, Elke, Gruber, Ingrid, Knoflach, Michael, Kiechl, Stefan, Rantner, Barbara, Abdulamit, Timur, Bergeron, Patrice, Padovani, Raymond, Trastour, Jean-Christophe, Cardon, Jean-Marie, Le Gallou-Wittenberg, Anne, Allaire, Eric, Becquemin, Jean-Pierre, Cochennec-Paliwoda, Frédéric, Desgranges, Pascal, Hosseini, Hassan, Kobeiter, Hicham, Marzelle, Jean, Almekhlafi, Mohammed A, Bal, Simerpreet, Barber, Phillip A, Coutts, Shelagh B, Demchuk, Andrew M, Eesa, Muneer, Gillies, Michelle, Goyal, Mayank, Hill, Michael D, Hudon, Mark E, Jambula, Anitha, Kenney, Carol, Klein, Gary, McClelland, Marie, Mitha, Alim, Menon, Bijoy K, Morrish, William F, Peters, Steven, Ryckborst, Karla J, Samis, Greg, Save, Supriya, Smith, Eric E, Stys, Peter, Subramaniam, Suresh, Sutherland, Garnette R, Watson, Tim, Wong, John H, Zimmel, L, Flis, Vojko, Matela, Jože, Miksic, Kazimir, Milotic, Franko, Mrdja, Božidar, Stirn, Barbara, Tetickovic, Erih, Gasparini, Mladen, Grad, Anton, Kompara, Ingrid, Miloševic, Zoren, Palmiste, Veronika, Toomsoo, Toomas, Aidashova, Balzhan, Kospanov, Nursultan, Lyssenko, Roman, Mussagaliev, Daulet, Beyar, Rafi, Hoffman, Aaron, Karram, Tony, Kerner, Arthur, Nikolsky, Eugenia, Nitecki, Samy, Andonova, Silva, Bachvarov, Chavdar, Petrov, Vesko, Cvjetko, Ivan, Vidjak, Vinko, Halužan, Damir, Petrunic, Mladen, Liu, Bao, Liu, Chang-Wei, Bartko, Daniel, Beno, Peter, Rusnák, František, Zelenák, Kamil, Ezura, Masayuki, Inoue, Takashi, Kimura, Naoto, Kondo, Ryushi, Matsumoto, Yasushi, Shimizu, Hiroaki, Endo, Hidenori, Furui, Eisuke, Bakke, Søren, Krohg-Sørensen, Kristen, Nome, Terje, Skjelland, Mona, Tennøe, Bjørn, Albuquerque e Castro, João, Alves, Gonçalo, Bastos Gonçalves, Frederico, de Aragão Morais, José, Garcia, Ana C, Valentim, Hugo, Vasconcelos, Leonor, Belcastro, Fernando, Cura, Fernando, Zaefferer, Patricio, Abd-Allah, Foad, Eldessoki, Mohamed H, Heshmat Kassem, Hussein, Soliman Gharieb, Haytham, Colgan, Mary P, Haider, Syed N, Harbison, Joe, Madhavan, Prakash, Moore, Dermot, Shanik, Gregor, Kazan, Viviane, Nazzal, Munier, and Ramsey-Williams, Vicki

Published
2021
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32. Making It Clear: Exploring Crystal Structures by Constructing and Comparing See-Through Models

Author

Lenzer, Stefanie, Smarsly, Bernd, and Graulich, Nicole

Abstract

Acquiring a basic understanding about the composition of crystal structures and the resulting structure-property relationship is central for chemists and material chemists, enabling the prediction of desired properties and the solution of a wide range of current challenges in sciences, e.g., the development of clean-energy storage. For a deeper understanding of physical and chemical properties of crystals, it is necessary to focus on different global and local structural features that characterize the composition of several atoms or ions as well as the direct environment of single atoms or ions. To improve students' mental visualization of both global and local features of the three-dimensional order of crystal structures, we developed and implemented a modeling activity with new transparent models. During the activity, students construct and compare models of common crystal structures, like sodium chloride and zinc blend. The usage of clear plastic balls, in particular, allows students to focus on global features such as packing arrangement and lattice structure, as well as on local ones, like coordination number, site occupation, and polyhedral connectivity. The latter features have been difficult to realize so far. We used a design-based research approach to improve the activity and the instructional material, provided herein, through several rounds of evaluation in a course for undergraduate students in materials chemistry. A detailed qualitative analysis of students' discourse during the activity revealed that students were engaged in various content-related interactions with the models and that it is beneficial to combine a student-centered construction of the models with a subsequent comparison phase.

Published
2019
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34. Klimasensible Gesundheitsberatung

Author

Herrmann, Alina, primary, Mews, Claudia, additional, Hansen, Heike, additional, Lenzer, Benedikt, additional, Schwienhorst-Stich, Eva-Maria, additional, and Quitmann, Claudia, additional

Published
2023
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42. Ensuring the integrity of clinical practice guidelines: a tool for protecting patients.

Author

Lenzer, Jeanne, Hoffman, Jerome R, Furberg, Curt D, Ioannidis, John PA, and Guideline Panel Review Working Group

Subjects
Guideline Panel Review Working Group, Humans, Evidence-Based Medicine, Systems Integration, Conflict of Interest, Patient Care Management, Quality of Health Care, United States, Practice Guidelines as Topic, Patient Safety, General & Internal Medicine, Public Health and Health Services, Clinical Sciences
Published
2013

44. Choices of Stent and Cerebral Protection in the Ongoing ACST-2 Trial: A Descriptive Study

Author

Fraedrich, G., Rantner, B., Gizewski, E., Gruber, I., Hendriks, J., Cras, P., Lauwers, P., van Scheil, P., Vermassen, F., Van Herzeele, I., Geenens, M., Hemelsoet, D., Lerut, P., Lambrecht, B., Saad, G., Peeters, A., Bosiers, M., da Silva, E., de Luccia, N., Sitrangulo, J.C., Jr., Estenssoro, A.E.V., Presti, C., Casella, I., Monteiro, J.A.T., Campos, W., Jr., Puech-Leao, P., Petrov, V., Bachvarov, C., Hill, M., Mitha, A., Wong, J., Liu, C.-W., Bao, L., Yu, C., Cvjetko, I., Vidjak, V., Fiedler, J., Ostry, S., Sterba, L., Kostal, P., Staffa, R., Vlachovsky, R., Privara, M., Kriz, Z., Vojtisek, B., Krupa, P., Reif, M., Benes, V., Buchvald, P., Endrych, L., Prochazka, V., Kuliha, M., Otahal, D., Hrbac, T., Netuka, D., Mohapl, M., Kramier, F., Eldessoki, M., Heshmat, H., Abd-Allah, F., Palmiste, V., Margus, S., Toomsoo, T., Becquemin, J.-P., Bergeron, P., Abdulamit, T., Cardon, J.-M., Debus, S., Thomalla, G., Fiehler, J., Gerloss, C., Grzyska, U., Storck, M., LaMacchia, E., Eckstein, H.H., Söllner, H., Berger, H., Kallmayer, M., Popert, H., Zimmermann, A., Guenther, A., Klingner, C., Mayer, T., Schubert, J., Zanow, J., Scheinert, D., Banning-Eichenseer, U., Bausback, Y., Branzan, D., Braünilch, S., Lenzer, J., Schidt, A., Staab, H., Ulirch, M., Barlinn, J., Haase, K., Abramyuk, A., Bodechtel, U., Gerber, J., Reeps, C., Pfeiffer, T., Torello, G., Cöster, A., Giannoukas, A., Spanos, K., Matsagkas, M., Koutias, S., Vasdekis, S., Kakisis, J., Moulakakis, K., Lazaris, A., Liapas, C., Brountzos, E., Lazarides, M., Ioannou, N., Polydorou, A., Fulop, B., Fako, E., Voros, E., Bodosi, M., Nemeth, T., Barzo, P., Pazdernyik, S., Entz, L., Szeberin, Z., Dosa, E., Nemes, B., Jaranyi, Z., Pazdernyia, S., Madhaban, P., Hoffman, A., Nikolsky, E., Beyar, R., Casana, R., Tolva, V., Silingardi, R., Lauricella, A., Coppi, G., Nicoloci, E., Tusini, N., Strozzi, F., Vecchiati, E., Ferri, M., Ferrero, E., Psacharopulo, D., Gaggiano, A., Viazzo, A., Farchioni, L., Parlani, G., Caso, V., De Rangoy, P., Verzini, F., Castelli, P., DeLodovici, M.L., Carrafiello, G., Ierardi, A.M., Piffaretti, G., Nano, G., Occhiuto, M.T., Malacrida, G., Tealdi, D., Steghter, S., Stella, A., Pini, R., Faggioli, G., Sacca, S., Negri, M.D., Palombo, M., Perfumo, M.C., Fadda, G.F., Kasemi, H., Cernetti, C., Tonello, D., Visonà, A., Mangialardi, N., Ronchey, S., Altavista, M.C., Michelagnoli, S., Chisci, E., Speziale, F., Capoccia, L., Veroux, P., Giaquinta, A., Patti, F., Pulli, R., Boggia, P., Angiletta, D., Amatucci, G., Spinetti, F., Mascoli, F., Tsolaki, E., Civilini, E., Reimers, B., Setacci, C., Pogany, G., Odero, A., Accrocca, F., Bajardi, G., Takashi, I., Masayuki, E., Hidenori, E., Aidashova, B., Kospanov, N., Bakke, S., Skjelland, M., Czlonkowska, A., Kobayashi, A., Proczka, R., Dowzenko, A., Czepel, W., Polanski, J., Bialek, P., Ozkinis, G., Snoch-Ziólkiewicz, M., Gabriel, M., Stanisic, M., Iwanowski, W., Andziak, P., Gonçalves, F.B., Starodubtsev, V., Ignatenko, P., Karpenko, A., Radak, D., Aleksic, N., Sagic, D., Davidovic, L., Koncar, I., Tomic, I., Colic, M., Bartkoy, D., Rusnak, F., Gaspirini, M., Praczek, P., Milosevic, Z., Flis, V., Bergauer, A., Kobilica, N., Miksic, K., Matela, J., Blanco, E., Guerra, M., Riambau, V., Gillgren, P., Skioldebrand, C., Nymen, N., Berg, B., Delle, M., Formgren, J., Kally, T.B., Qvarfordt, P., Plate, G., Pärson, H., Lindgren, H., Bjorses, K., Gottsäter, A., Warvsten, M., Kristmundsson, T., Forssell, C., Malina, M., Holst, J., Kuhme, T., Sonesson, B., Lindblad, B., Kolbel, T., Acosta, S., Bonati, L., Traenka, C., Mueller, M., Lattman, T., Wasner, M., Mujagic, E., Von Hessling, A., Isaak, A., Stierli, P., Eugster, T., Mariani, L., Stippich, C., Wolff, T., Kahles, T., de Borst, G.J., Toorop, R., Moll, F., Lo, R., Meershoek, A., Jahrome, A.K., Vos, A.W.F., Schuiling, W., Keunen, R., Reijnen, M., Macsweeney, S., McConachie, N., Southam, A., Stansby, G., Lees, T., Lambert, D., Clarke, M., Wyatt, M., Kappadath, S., Wales, L., Jackson, R., Raudonaitis, A., MacDonald, S., Dunlop, P., Brown, A., Vetrivel, S., Bajoriene, M., Gopi, R., McCollum, C., Wolowczyk, L., Ghosh, J., Seriki, D., Ashleigh, R., Butterfield, J., Welch, M., Smyth, J.V., Briley, D., Schulz, U., Perkins, J., Hands, L., Kuker, W., Darby, C., Handa, A., Sekaran, L., Poskitt, K., Bulbulia, R., Morrison, J., Guyler, P., Grunwald, I., Brown, J., Jakeways, M., Tysoe, S., Hargroves, D., Gunathilagan, G., Insall, R., Senaratne, J., Beard, J., Cleveland, T., Nawaz, S., Lonsdale, R., Turner, D., Gaines, P., Nair, R., Chetter, I., Robinson, G., Akomolafe, B., Hatfield, J., Saastamoinen, K., Crinnion, J., Egun, A.A., Thomas, J., Drinkwater, S., D'Souza, S., Thomson, G., Gregory, B., Babu, S., Ashley, S., Joseph, T., Gibbs, R., Tebit, G., Mehrzad, A., Enevoldson, P., Mendalow, D., Parry, A., Tervitt, G., Clifton, A., Nazzel, M., Halliday, A., Peto, R., Pan, H., Potter, J., Bullbulia, R., Mihaylova, B., Flather, M., Mansfield, A., Simpson, D., Thomas, D., Gray, W., Farrell, B., Davies, C., Rahimi, K., Gough, M., Cao, P., Rothwell, P., Belli, A., Mafham, M., Herrington, W., Sandercock, P., Gray, R., Shearman, C., Molyneux, A., Gray, A., Clarke, A., Sneade, M., Tully, L., Brudlo, W., Lay, M., Munday, A., Berry, C., Tochlin, S., Cox, J., Kurien, R., Chester, J., de Waard, D.D., Huibers, A., and Bonati, L.H.

Published
2017
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47. Initial Quenching Efficiency Determines Light‐Driven H2 Evolution of [Mo3S13]2− in Lipid Bilayers.

Author

Abbas, Amir, Oswald, Eva, Romer, Jan, Lenzer, Anja, Heiland, Magdalena, Streb, Carsten, Kranz, Christine, and Pannwitz, Andrea

Subjects
BILAYER lipid membranes, BIOLOGICAL membranes, SCANNING electrochemical microscopy, RUTHENIUM catalysts, CHARGE exchange, PHASE transitions, LIPOSOMES, CATALYTIC activity
Abstract

Nature uses reactive components embedded in biological membranes to perform light‐driven photosynthesis. Here, a model artificial photosynthetic system for light‐driven hydrogen (H2) evolution is reported. The system is based on liposomes where amphiphilic ruthenium trisbipyridine based photosensitizer (RuC9) and the H2 evolution reaction (HER) catalyst [Mo3S13]2− are embedded in biomimetic phospholipid membranes. When DMPC was used as the main lipid of these light‐active liposomes, increased catalytic activity (TONCAT ~200) was observed compared to purely aqueous conditions. Although all tested lipid matrixes, including DMPC, DOPG, DPPC and DOPG liposomes provided similar liposomal structures according to TEM analysis, only DMPC yielded high H2 amounts. In situ scanning electrochemical microscopy (SECM) measurements using Pd microsensors revealed an induction period of around 26 minutes prior to H2 evolution, indicating an activation mechanism which might be induced by the fluid‐gel phase transition of DMPC at room temperature. Stern‐Volmer‐type quenching studies revealed that electron transfer dynamics from the excited state photosensitizer are most efficient in the DMPC lipid environment giving insight for design of artificial photosynthetic systems using lipid bilayer membranes. [ABSTRACT FROM AUTHOR]

Published
2023
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48. Excited-State Dynamics of Bis(tetraethylammonium) Di-µ-bromo-dibromodicuprate(I) Thin Films.

Author

Gust, Domenic, Scholz, Mirko, Oum, Kawon, and Lenzer, Thomas

Subjects
THIN films, TETRAETHYLAMMONIUM, ACOUSTIC phonons, PHONON scattering, EXCITED states
Abstract

Organic–inorganic halocuprates based on monovalent copper are promising luminescent compounds for optoelectronic applications; however, their relaxation processes in the excited electronic state are severely underexplored. In this contribution, we prepare thin films of bis(tetraethylammonium) di-µ-bromo-dibromodicuprate(I) [N(C2H5)4]2[Cu2Br4], abbreviated (TEA)2Cu2Br4, which features a "molecular salt" structure containing discrete [Cu2Br4]2− anions. This compound, which has an absorption peak at 283 nm, displays a blue, strongly Stokes-shifted emission with a peak at 467 nm. Transient photoluminescence (PL) experiments using broadband emission detection and time-correlated single-photon counting (TCSPC) both find an excited-state lifetime of 57 μs at 296 K. UV–Vis transient absorption experiments at 296 K covering time scales from femto- to microseconds provide evidence for the formation of the T1 state through intersystem crossing from S1 with a time constant of 184 ps. The triplet state subsequently decays to S0 predominantly by phosphorescence. In addition, the time constants for carrier–optical phonon scattering (1.8 ps) and acoustic phonon relaxation (8.3 ns and 465 ns) of (TEA)2Cu2Br4 are provided. [ABSTRACT FROM AUTHOR]

Published
2023
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50. Evaluation of Sn0.9Fe0.1O2‐δ as Potential Anode Material for Sodium‐Ion Batteries.

Author

Lenzer, Anja, Birrozzi, Adele, Wirsching, Anna‐Lena, Li, Yueliang, Geiger, Dorin, Kaiser, Ute, Asenbauer, Jakob, and Bresser, Dominic

Subjects
TRANSITION metal oxides, SODIUM ions, TIN oxides, IRON alloys, STANNIC oxide, X-ray diffraction
Abstract

The introduction of transition metals such as iron in oxides of alloying elements as, for instance, SnO2 has been proven to enable higher capacities and superior charge storage performance when used as lithium‐ion electrode materials. Herein, we report the evaluation of such electrode materials, precisely (carbon‐coated) Sn0.9Fe0.1O2−δ(−C), for sodium‐ion battery applications. The comparison with SnO2 as reference material reveals the beneficial impact of the presence of iron in the tin oxide lattice, enabling higher specific capacities and a greater reversibility of the de‐/sodiation process – just like for lithium‐ion battery applications. The overall achievable capacity, however, remains relatively low with about 300 mAh g−1 and up to more than 400 mAh g−1 for Sn0.9Fe0.1O2‐δ and Sn0.9Fe0.1O2−δ‐C, respectively, compared to the theoretical specific capacity of more than 1,300 mAh g−1 when assuming a completely reversible alloying and conversion reaction. The subsequently performed ex situ/operando XRD and ex situ TEM/EDX analysis unveils that this limited capacity results from an incomplete de‐/sodiation reaction, thus, providing valuable insights towards an enhanced understanding of alternative reaction mechanisms for sodium‐ion anode material candidates. [ABSTRACT FROM AUTHOR]

Published
2023
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