bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basin modelling of a lignite‐bearing salt rim syncline: insights into rim syncline evolution and salt diapirism in NW Germany
Authors: Brandes Christian , Pollok Lukas , Schmidt Carolin , Wilde Volker , Winsemann Jutta 
Published: March 2012

AbstractThe Helmstedt‐Staßfurt salt wall is 70 km long, 6–8 km wide and one of the most important diapiric structures in northern Germany, based on the economically significant lignite‐bearing rim synclines. The analysed Schöningen rim syncline, located on the southwestern side of the Helmstedt‐Staßfurt structure, is 8 km long and 3 km wide. The basin‐fill is up to 366 m thick and characterized by 13 major lignite seams with thicknesses between 0.1 and 30 m. The key objectives of this article were to expand on the classical cross‐section based rim syncline analysis by the use of 3D models and basin simulations. Cross‐sections perpendicular to the basin axis indicate that the basin‐fill has a pronounced lenticular shape. This shape varies from more symmetric in the NW to clearly asymmetric in the SE. Isopach maps imply a two‐fold depocentre evolution. The depocentre migrated over time towards the salt wall and also showed some distinct shifts parallel to the salt wall. The basin modelling part of the study was carried out with the software PetroMod®, which focused on the burial history of the rim syncline. Modelling results also show the progressive migration of the rim syncline depocentre towards the salt wall. The present‐day asymmetry of the basin‐fill was already developed in the early phases of rim syncline evolution. The extracted geohistory curve shows initial rapid subsidence between 57 and 50 Ma and more moderate subsidence from 50 to 34 Ma. This pattern is interpreted to reflect salt evacuation from the source layer into the salt wall. The initial salt‐withdrawal rate was rapid, but later decreased probably due to depletion of the source layer.
In vitro anti‐myeloma activity of TRAIL‐expressing adipose‐derived mesenchymal stem cells
Authors: Ciavarella Sabino , Grisendi Giulia , Dominici Massimo , Tucci Marco , Brunetti Oronzo , Dammacco Franco , Silvestris Franco 
Published: March 2012

SummaryRecently, genetically modified mesenchymal stem cells (MSCs) have been exploited to deliver anti‐cancer bio‐drugs directly within the tumour mass. Here, we explored whether adipose‐derived MSCs (AD‐MSCs), engineered to express the pro‐apoptotic ligand TRAIL (also known as TNFSF10), kill multiple myeloma (MM) cells and migrate towards MM cells in vitro. Different MM cell lines were assessed for their sensitivity to recombinant human (rh) TRAIL alone and in combination with the proteasome inhibitor bortezomib, which was shown to enhance the effect of rhTRAIL. TRAIL+‐AD‐MSCs were co‐cultured with bortezomib‐pretreated MM cells and their killing activity was evaluated in presence or absence of caspase inhibition. AD‐MSC migration towards media conditioned by both myeloma cells and myeloma bone fragments was also investigated. Despite moderate MM cell sensitivity to rhTRAIL, TRAIL+‐AD‐MSCs in combination with bortezomib significantly induced myeloma cell death. This effect was associated with caspase‐8 activation and abrogated by capsase inhibition. On the other hand, co‐culture experiments were performed to evaluate whether unmodified AD‐MSCs affect myeloma cell growth in vitro. AD‐MSCs appeared ineffective on myeloma cell growth and showed migratory capacity towards MM cells in vitro. These data emphasize the anti‐myeloma activity of TRAIL‐engineered AD‐MSCs and provide support for a future model of a cell‐based approach against MM.
Supporting middle school students' online reading of scientific resources: moving beyond cursory, fragmented, and opportunistic reading
Authors: Zhang M. 
Published: March 2012

AbstractThe abundant scientific resources on the Web provide great opportunities for students to expand their science learning, yet easy access to information does not ensure learning. Prior research has found that middle school students tend to read Web‐based scientific resources in a shallow, superficial manner. A software tool was designed to support middle school students in reading online scientific resources through three key strategies: making explicit a skim–read–summarize structure for online reading, using prompts to guide students' reading and foster articulation of thinking, and connecting reading to learning purposes. This study examined the differences between regular and guided online reading performed by eight pairs of sixth graders in a science inquiry project. The students' online reading processes and conversations were captured by a screen‐recording programme. Analysis of 60 h of screen videos showed that the students' online reading in the regular condition was cursory, fragmented, and opportunistic, while the structured online reading was more deliberate, thorough, and purposeful. Overall, the results suggest that middle school students' online reading of scientific resources needs to be guided.
Incommensurate practices: sociomaterial entanglements of learning technology implementation
Authors: Hannon J. 
Published: March 2012

AbstractThe framing of ‘implementation’ of learning technologies in universities can have profound effects on approaches to teaching and learning that may be insufficiently acknowledged by practitioners. This paper investigates a case that demonstrated the formation of strong connections between technology and pedagogy, in which a learning content management system called for a series of accommodations between technology work and academic work. The site for this study was the meso‐level in the university: those practitioners working in‐between academics and institutional learning technologies, and draws on the accounts of practice by learning technologists during this implementation. The discussion of practice that emerges from these accounts draws on sociomaterial perspectives to draw attention to the contingencies of particular connections during the implementation process. This study does not assume that the work of implementation follows naturally from plans and intentions of human actors, rather it investigates actual arrangements and the entangled practices that bring significant unintended consequences. The findings suggest the need to attend to the potential for conflicting practices when system technologies become a key component of e‐learning, and I argue for implementation to be scoped early to encompass pedagogical goals, and for interventions by learning technologists and teaching academics over all the social, material, and discursive factors that are critical to e‐learning practice.
Technological pedagogical content knowledge – a review of the literature
Authors: Voogt J. , Fisser P. , Pareja Roblin N. , Tondeur J. , van Braak J. 
Published: March 2012

AbstractTechnological Pedagogical Content Knowledge (TPACK) has been introduced as a conceptual framework for the knowledge base teachers need to effectively teach with technology. The framework stems from the notion that technology integration in a specific educational context benefits from a careful alignment of content, pedagogy and the potential of technology, and that teachers who want to integrate technology in their teaching practice therefore need to be competent in all three domains. This study is a systematic literature review about TPACK of 55 peer‐reviewed journal articles (and one book chapter), published between 2005 and 2011. The purpose of the review was to investigate the theoretical basis and the practical use of TPACK. Findings showed different understandings of TPACK and of technological knowledge. Implications of these different views impacted the way TPACK was measured. Notions about TPACK in subject domains were hardly found in the studies selected for this review. Teacher knowledge (TPACK) and beliefs about pedagogy and technology are intertwined. Both determine whether a teacher decides to teach with technology. Active involvement in (re)design and enactment of technology‐enhanced lessons was found as a promising strategy for the development of TPACK in (student‐)teachers. Future directions for research are discussed.
How lead consultants approach educational change in postgraduate medical education
Authors: Fokkema Joanne P I , Westerman Michiel , Teunissen Pim W , van der Lee Nadine , Scherpbier Albert J J A , van der Vleuten Cees P M , Dörr P Joep , Scheele Fedde 
Published: March 2012

Medical Education 2012: 46: 390–398Context  Consultants in charge of postgraduate medical education (PGME) in hospital departments (‘lead consultants’) are responsible for the implementation of educational change. Although difficulties in innovating in medical education are described in the literature, little is known about how lead consultants approach educational change.Objectives  This study was conducted to explore lead consultants’ approaches to educational change in specialty training and factors influencing these approaches.Methods  From an interpretative constructivist perspective, we conducted a qualitative exploratory study using semi‐structured interviews with a purposive sample of 16 lead consultants in the Netherlands between August 2010 and February 2011. The study design was based on the research questions and notions from corporate business and social psychology about the roles of change managers. Interview transcripts were analysed thematically using template analysis.Results  The lead consultants described change processes with different stages, including cause, development of content, and the execution and evaluation of change, and used individual change strategies consisting of elements such as ideas, intentions and behaviour. Communication is necessary to the forming of a strategy and the implementation of change, but the nature of communication is influenced by the strategy in use. Lead consultants differed in their degree of awareness of the strategies they used. Factors influencing approaches to change were: knowledge, ideas and beliefs about change; level of reflection; task interpretation; personal style, and department culture.Conclusions  Most lead consultants showed limited awareness of their own approaches to change. This can lead them to adopt a rigid approach, whereas the ability to adapt strategies to circumstances is considered important to effective change management. Interventions and research should be aimed at enhancing the awareness of lead consultants of approaches to change in PGME.
From test validity to construct validity … and back?
Authors: Colliver Jerry A. , Conlee Melinda J. , Verhulst Steven J. 
Published: March 2012

Medical Education 2012: 46: 366–371Context  Major changes in thinking about validity have occurred during the past century, shifting the focus in thinking from the validity of the test to the validity of test score interpretations. These changes have resulted from the ‘new’ thinking about validity in which construct validity has emerged as the central or unifying idea of validity today. Construct validity was introduced by Cronbach and Meehl in the mid‐1950s in an attempt to address the validity of those many psychological concepts that have no clear referent in reality. To do this, construct validity theory required a nomological network – an elaborate theoretical network of constructs and observations connected by scientific laws – to validate the constructs. However, nomological networks are hard to come by and none that would do the job required by construct validity has been forthcoming to date. Thus, the current construct validity approach has retreated to one of simply ‘interpretation and argument’, but this seems to be too general to tie down the constructs in the way a nomological network would do to give credibility to the validity of the construct. As a result, the concept of validity seems to have been watered down and the credibility of validity claims weakened.Objectives  The purpose of this paper is to encourage a discussion of the use of construct validity in medical education, and to suggest that test developers and users reconsider the use of abstract theoretical constructs that have no referent apart from theory.Methods  We present a critical review of these concerns about construct validity and provide for contrast a brief overview of a recently proposed view of measurement based on scientific realism and causality analysis.
Evaluating cognitive ability, knowledge tests and situational judgement tests for postgraduate selection
Authors: Koczwara Anna , Patterson Fiona , Zibarras Lara , Kerrin Maire , Irish Bill , Wilkinson Martin 
Published: March 2012

Medical Education 2012: 46: 399–408Objectives  This study aimed to evaluate the validity and utility of and candidate reactions towards cognitive ability tests, and current selection methods, including a clinical problem‐solving test (CPST) and a situational judgement test (SJT), for postgraduate selection.Methods  This was an exploratory, longitudinal study to evaluate the validities of two cognitive ability tests (measuring general intelligence) compared with current selection tests, including a CPST and an SJT, in predicting performance at a subsequent selection centre (SC). Candidate reactions were evaluated immediately after test administration to examine face validity. Data were collected from candidates applying for entry into training in UK general practice (GP) during the 2009 recruitment process. Participants were junior doctors (n = 260). The mean age of participants was 30.9 years and 53.1% were female. Outcome measures were participants’ scores on three job simulation exercises at the SC.Results  Findings indicate that all tests measure overlapping constructs. Both the CPST and SJT independently predicted more variance than the cognitive ability test measuring non‐verbal mental ability. The other cognitive ability test (measuring verbal, numerical and diagrammatic reasoning) had a predictive value similar to that of the CPST and added significant incremental validity in predicting performance on job simulations in an SC. The best single predictor of performance at the SC was the SJT. Candidate reactions were more positive towards the CPST and SJT than the cognitive ability tests.Conclusions  In terms of operational validity and candidate acceptance, the combination of the current CPST and SJT proved to be the most effective administration of tests in predicting selection outcomes. In terms of construct validity, the SJT measures procedural knowledge in addition to aspects of declarative knowledge and fluid abilities and is the best single predictor of performance in the SC. Further research should consider the validity of the tests in this study in predicting subsequent performance in training.
Video‐based cases disrupt deep critical thinking in problem‐based learning
Authors: Basu Roy Robindra , McMahon Graham T 
Published: March 2012

Medical Education 2012: 46: 426–435Context  Video is a popular tool in problem‐based learning (PBL), although its production requires resources and time. Few studies have examined the impact of the use of video in PBL upon cognitive processes and critical thinking. Those that have done focused on cases involving physical signs, where video has natural advantages.Objectives  This study aimed to investigate preferences for video‐ or text‐based cases and the effects of each format upon medical students’ deep thinking in PBL. Tutorials were based on material portraying interviews with patients with conditions that include psychosocial elements but no physical signs.Methods  Four tutorial groups of students in a Year 2 endocrine and reproductive pathophysiology course participated in a crossover study using one video‐based and one text‐based case. Transcripts of tutorials were coded for depth of thinking by a blinded coder. A generalised estimating equation model was used to adjust for potential differences among groups, cases, and tutor participation. The distribution of cognitive activity within the crossover groups and the adjusted odds ratios (ORs) for deep versus superficial thinking were calculated. A prior cohort of 165 students and 18 tutors completed a survey of learning preferences.Results  Of 5224 student utterances, the majority referred to problem exploration (2622, 50%) and description (1479, 28%). Overall, the odds of deep thinking versus superficial thinking were significantly lower using video‐based cases compared with text‐based cases (2045 deep/2454 for video versus 1961 deep/2218 for text; OR 0.663, 95% confidence interval [CI] 0.582–0.754; p < 0.0001). This was also true for the problem exploration domain (1217 deep/1365 for video versus 1178 deep/1257 for text; OR 0.559, 95% CI 0.355–0.882; p = 0.0125). The majority of students (59%) and tutors (78%) indicated a preference for video‐based cases over text‐based cases.Conclusions  Students and their tutors prefer video‐based cases in PBL. However, compared with text‐based material, the use of video‐based material that refers to cases without dynamic physical signs is associated with a reduction in deep thinking.
Integrating virtual patients into courses: follow‐up seminars and perceived benefit
Authors: Edelbring Samuel , Broström Olle , Henriksson Peter , Vassiliou Daphne , Spaak Jonas , Dahlgren Lars Owe , Fors Uno , Zary Nabil 
Published: March 2012

Medical Education 2012: 46: 417–425Context  The use of virtual patients (VPs) suggests promising effects on student learning. However, currently empirical data on how best to use VPs in practice are scarce. More knowledge is needed regarding aspects of integrating VPs into a course, of which student acceptance is one key issue. Several authors call for looking beyond technology to see VPs in relation to the course context. The follow‐up seminar is proposed as an important aspect of integration that warrants investigation.Methods  A cross‐sectional explanatory study was performed in a clinical clerkship introduction course at four teaching hospitals affiliated to the same medical faculty. The VP‐related activities were planned collaboratively by teachers from all four settings. However, each setting employed a different strategy to follow up the activity in the course. Sixteen questionnaire items were grouped into three scales pertaining to: perceived benefit of VPs; wish for more guidance on using VPs, and wish for assessment and feedback on VPs. Scale scores were compared across the four settings, which were ranked according to the level of intensity of students’ processing of cases during VP follow‐up activities.Results  The perceived benefit of VPs and their usage were higher in the two intense‐use settings compared with the moderate‐ and low‐intensity settings. The wish for more guidance was high in the low‐ and one of the high‐intensity settings. Students in all settings displayed little interest in more assessment and feedback regarding VPs.Conclusions  High case processing intensity was related to positive perceptions of the benefit of VPs. However, the low interest in more assessment and feedback on the use of VPs indicates the need to clearly communicate the added value of the follow‐up seminar. The findings suggest that a more intense follow‐up pays off in terms of the benefit perceived by students. This study illustrates the need to consider VPs from the perspective of a holistic course design and not as isolated add‐ons.
The Rome II and Rome III criteria identify the same subtype‐populations in irritable bowel syndrome: agreement depends on the method used for symptom report
Authors: Engsbro A. L. , Simrén M. , Bytzer P. 
Published: March 2012

AbstractBackground  For comparing trials using different classifications for irritable bowel syndrome (IBS) subtypes, it is important to know whether these identify the same sub‐populations. Our aim was to determine the agreement between Rome II and Rome III subtypes, and to explore whether agreement depends on the symptom reporting method.Methods  Rome II IBS patients from two identical, randomized placebo‐controlled trials of probiotics were included. Retrospective subtypes were based on the Rome II questionnaire. Prospective subtypes were based on diary cards for 2 weeks of run‐in. Agreement was determined between: (i) retrospective Rome II and Rome III, (ii) prospective Rome II and Rome III, (iii) retrospective Rome II and prospectively Rome III, (iv) retrospective and prospective Rome II, and (v) retrospective and prospective Rome III.Key Results  A total of 126 patients, 72% women, mean age 46 ± 15 years, were included. The agreement between subtypes using the same symptom reporting method was: (i) 90.3% (κ = 0.85) for retrospective subtypes, and (ii) 84% (κ = 0.76) for prospective subtypes. The agreement between subtypes using different symptom reporting methods was, (iii) 49% (κ = 0.23) for retrospective Rome II and prospective Rome III, (iv) 51% (κ = 0.26) for Rome II subtypes, and (v) 41% (κ = 0.25) for Rome III subtypes.Conclusions & Inferences  Agreement between Rome II and Rome III subtypes is good to very good when using the same symptom reporting method. When mixing methods, agreement is only fair even within the same classification. This has implications for comparison of trials using different symptom reporting methods for subtyping.
A field‐compatible method for measuring alternative respiratory pathway activities in vivo using stable O2 isotopes
Authors: KORNFELD ARI , HORTON TRAVIS W. , YAKIR DAN , SEARLE STEPHANIE Y. , GRIFFIN KEVIN L. , ATKIN OWEN K. , SUBKE JENS‐ARNE , TURNBULL MATTHEW H. 
Published: March 2012

ABSTRACTPlants can alter rates of electron transport through the alternative oxidase (AOX) pathway in response to environmental cues, thus modulating respiratory efficiency, but the 18O discrimination method necessary for measuring electron partitioning in vivo has been restricted to laboratory settings. To overcome this limitation, we developed a field‐compatible analytical method. Series of plant tissue subsamples were incubated in 12 mL septum‐capped vials for 0.5–4 h before aliquots of incubation air were injected into 3.7 mL evacuated storage vials. Vials were stored for up to 10 months before analysis by mass spectrometry. Measurements were corrected for unavoidable contamination. Additional mathematical tools were developed for detecting and addressing non‐linearity (whether intrinsic or due to contamination) in the data used to estimate discrimination values. Initial contamination in the storage vials was 0.03 ± 0.01 atm; storing the gas samples at −17 °C eliminated further contamination effects over 10 months. Discrimination values obtained using our offline incubation and computation method replicated previously reported results over a range of 10–31‰, with precision generally better than ±0.5‰. Our method enables large‐scale investigations of plant alternative respiration along natural environmental gradients under field conditions.
First Report of Anthracnose Disease on Jatropha curcas Caused by Colletotrichum gloeosporioides in Korea
Authors: Kwon Jin‐Hyeuk , Choi Okhee , Kim Jinwoo , Kwak Youn‐Sig 
Published: March 2012

AbstractIn the summers of 2010 and 2011, an anthracnose disease was observed on the Jatropha curcas L. grown at the research field of Gyeongsangnam‐do Agricultural Research and Extension Services, South Korea. The symptoms included the appearance of dark brown spots on the leaf and fruit and the mummification of the fruit. The causal fungus formed grey to dark grey colony on potato dextrose agar. Conidia were single celled, ovoid or oblong, and 8–15 × 3–5 μm in size while seta was dark brown, cone‐shaped and 25–46 × 2–6 μm in size. The optimum temperature for growth was approximately 30°C. On the basis of mycological characteristics, pathogenicity test and molecular identification using internal transcribed spacer rDNA sequence, the fungus was identified as Colletotrichum gloeosporioides. To our knowledge, this is the first report of an anthracnose caused by C. gloeosporioides on J. curcas plant in Korea.