bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding fatty acid metabolism through an active learning approach
Authors: Fardilha M. , Schrader M. , da Cruz e Silva O. A. B. , da Cruz e Silva E. F. 
Published: March 2010

AbstractA multi‐method active learning approach (MALA) was implemented in the Medical Biochemistry teaching unit of the Biomedical Sciences degree at the University of Aveiro, using problem‐based learning as the main learning approach. In this type of learning strategy, students are involved beyond the mere exercise of being taught by listening. Less emphasis is placed on transmitting information and the focus is shifted toward developing higher order thinking (analysis, synthesis, and evaluation). However, MALA should always involve clearly identified objectives and well‐defined targets. Understanding fatty acid metabolism was one of the proposed goals of the Medical Biochemistry unit. To this end, students were challenged with a variety of learning strategies to develop skills associated with group conflict resolution, critical thinking, information access, and retrieval, as well as oral and written communication skills. Overall, students and learning facilitators were highly motivated by the diversity of learning activities, particularly due to the emphasis on correlating theoretical knowledge with human health and disease. As a quality control exercise, the students were asked to answer a questionnaire on their evaluation of the whole teaching/learning experience. Our initial analysis of the learning outcomes permits us to conclude that the approach undertaken yields results that surpass the traditional teaching methods.
Teaching the extracellular matrix and introducing online databases within a multidisciplinary course with i‐cell‐MATRIX
Authors: Sousa João Carlos , Costa Manuel João , Palha Joana Almeida 
Published: March 2010

AbstractThe biochemistry and molecular biology of the extracellular matrix (ECM) is difficult to convey to students in a classroom setting in ways that capture their interest. The understanding of the matrix's roles in physiological and pathological conditions study will presumably be hampered by insufficient knowledge of its molecular structure. Internet‐available resources can bridge the division between the molecular details and ECM's biological properties and associated processes. This article presents an approach to teach the ECM developed for first year medical undergraduates who, working in teams: (i) Explore a specific molecular component of the matrix, (ii) identify a disease in which the component is implicated, (iii) investigate how the component's structure/function contributes to ECM' supramolecular organization in physiological and in pathological conditions, and (iv) share their findings with colleagues. The approach—designated i‐cell‐MATRIX—is focused on the contribution of individual components to the overall organization and biological functions of the ECM. i‐cell‐MATRIX is student centered and uses 5 hours of class time. Summary of results and take home message: A “1‐minute paper” has been used to gather student feedback on the impact of i‐cell‐MATRIX. Qualitative analysis of student feedback gathered in three consecutive years revealed that students appreciate the approach's reliance on self‐directed learning, the interactivity embedded and the demand for deeper insights on the ECM. Learning how to use internet biomedical resources is another positive outcome. Ninety percent of students recommend the activity for subsequent years. i‐cell‐MATRIX is adaptable by other medical schools which may be looking for an approach that achieves higher student engagement with the ECM.
What's on the news? The use of media texts in exams of clinical biochemistry for medical and nutrition students
Authors: Oliveira Julia Martins , Mesquita Diego Martins , Hermes‐Lima Marcelo 
Published: March 2010

AbstractHealth‐related popular articles are easily found among media sources. With the increasing popularity of the internet, medical information – full of misconceptions ‐ has become easily available to the lay people. The ability to recognize misconceptions may require good biomedical knowledge. In this sense, we decided to use articles from the internet as part of a formal exam to evaluate students' learning of Clinical and Applied Biochemistry (CAB). This test, known as the True‐or‐False (T‐or‐F) exam, is made up of statements found online that are judged by freshmen medical and nutrition students taking Basic Biochemistry. In the last four teaching‐semesters, students' acceptance and responses to T‐or‐F exam on CAB were evaluated through questionnaires (using a 0–4 Likert scale). Results from 258 students revealed that 71, 87, and 94% of them believed, respectively, that the exam was (i) difficult, (ii) of good quality, and (iii) that using media‐questions is relevant for evaluating the learning of CAB. Moreover, the average grade in the T‐of‐F exam was 5.85 (out of 10). This low average is probably because students are not familiarized with this sort of examination that does not emphasize on memorizations of biochemical pathways and processes – it instead evaluates mostly the comprehension and application of knowledge, levels 2 and 3 in Bloom's scale. Such conclusion was possible by analyzing 192 questions in four exams ‐ 67% were at levels 2, 3 or above. This kind of media‐based exam could be well applied to several other disciplines in health sciences.
Introducing human population biology through an easy laboratory exercise on mitochondrial DNA
Authors: Pardiñas Antonio F. , Dopico Eduardo , Roca Agustín , Garcia‐Vazquez Eva , Lopez Belen 
Published: March 2010

AbstractThis article describes an easy and cheap laboratory exercise for students to discover their own mitochondrial haplogroup. Students use buccal swabs to obtain mucosa cells as noninvasive tissue samples, extract DNA, and with a simple polymerase chain reaction‐restriction fragment length polymorphism analysis they can obtain DNA fragments of different sizes that can be visualized in agarose gels. The analysis of these fragments can reveal the mitochondrial haplogroup of each student. The results of the exercise can be used to provide additional insights into the genetic variation of human populations.
Teaching energy metabolism using scientific articles
Authors: de Espíndola Marina Bazzo , El‐Bacha Tatiana , Giannella Taís Rabetti , Struchiner Miriam , da Silva Wagner S. , Da Poian Andrea T. 
Published: March 2010

AbstractThis work describes the use of a virtual learning environment (VLE) applied to the biochemistry class for undergraduate, first‐year medical students at the Federal University of Rio de Janeiro. The course focused on the integration of energy metabolism, exploring metabolic adaptations in different physiological or pathological states such as starvation, diabetes, and exercise. The VLE was designed to combine online activities with traditional course content and presented guided inquiry‐based activities to assist in the use of original scientific articles as educational resources. Based on the analysis of a semi‐open questionnaire, the results provided evidence that the VLE encouraged students' engagement in activities and improved feedback. The results also suggested that guided inquiry‐based activities were an effective way to stimulate students to critically read relevant scientific articles and to acquire skills to build and contextualize their knowledge through content association. In addition, most of the students involved in this experience considered the use of these resources important to become familiar with scientific language and to learn how to obtain up‐to‐date scientific information during their professional life.
C1‐Symmetric Aminosulfoximines in Copper‐Catalyzed Asymmetric Vinylogous Mukaiyama Aldol Reactions
Authors: Frings Marcus , Atodiresei Iuliana , Wang Yutian , Runsink Jan , Raabe Gerhard , Bolm Carsten 
Published: March 2010

AbstractVinylogous Mukaiyama‐type aldol reactions have been catalyzed by a combination of Cu(OTf)2 and readily available C1‐symmetric aminosulfoximines. After a fine‐tuning of the reaction conditions and an optimization of the modularly assembled ligand structure, high stereoselectivities and excellent yields have been achieved in catalyzed reactions involving various electrophile/nucleophile combinations. The relative and absolute configurations of two products were assigned by X‐ray single crystal structure analysis and a comparison of calculated and experimental CD spectra.
Fine‐Tuning the Dimerization of Tetraureacalix[4]arenes
Authors: Rudzevich Yuliya , Rudzevich Valentyn , Böhmer Volker 
Published: March 2010

AbstractCalix[4]arenes substituted by four urea residues at their wide rim form hydrogen‐bonded homo‐ and heterodimeric capsules in apolar solvents. If urea groups are covalently connected to loops or substituted by bulky residues, the dimerization may be restricted to those pairs in which the loops do not overlap and for which the residues are small enough to pass the loops. In the present study, we describe the dimerization properties of tetraureas with one, two (adjacent or opposite), three, or four loops and those bearing (additionally) up to four residues of different size: a=tolyl, b=3,5‐di‐tert‐butylphenyl, c=4‐propyloxy‐3,5‐di‐(tert‐butylphenyl)phenyl, and d=4‐[tris‐(4‐tert‐butylphenyl)methyl]phenyl. For compounds with four loops of different size (O(CH2)nO‐chains with n=10, 14, and 20 connecting the m‐positions of the urea phenyl residues) a clear “stepwise” sorting scheme could be established, in which the bulkiest residue d is excluded by all tetraloop compounds and the smallest residue a can pass only the smallest loops (n=10). The medium‐sized residues b or c are tolerated by n=14 and 20 or only by n=20. Selectivities can be built up also on geometrical factors. A trisloop compound, for instance, combines only with a tetraurea bearing a single bulky residue and tetraureas with two bulky substituents in adjacent or opposite position are distinguished by the bisloop derivatives with adjacent or opposite loops. The impossibility to form a homodimer of a monoloop compound containing two bulky residues leads to its selective heterodimerization with a derivative bearing three bulky groups. Subtle effects for “borderline” cases, in which the dimerization or reorganization takes a longer time, are also discussed.
Small‐Molecule Inhibitors of the Hedgehog Signaling Pathway as Cancer Therapeutics
Authors: Peukert Stefan , Miller‐Moslin Karen 
Published: March 2010

AbstractInhibitors of the Hedgehog (Hh) molecular signaling pathway have emerged in recent years as a promising new class of potential therapeutics for cancer treatment. Numerous drug discovery efforts have resulted in the identification of a wide variety of small molecules that target different members of this pathway, including Smoothened (Smo), Sonic hedgehog protein (Shh), and Gli1. Several Smo inhibitors have now entered human clinical trials, and successful proof‐of‐concept studies have been carried out in patients with defined genetic mutations in the Hh pathway. This review provides a general overview of three main topics in this rapidly expanding area: 1) the various types of biological assays and in vivo models that have been employed for the identification and optimization of Hh pathway inhibitors; 2) Smo inhibitors reported to date, including recent clinical results where available; and 3) efforts toward the identification and characterization of inhibitors of other members of the Hh pathway.
A new perspective on neural tube defects: Folic acid and microRNA misexpression
Authors: Shookhoff J.M. , Gallicano G. Ian 
Published: March 2010

AbstractNeural tube defects (NTDs) are the second most common birth defects in the United States. It is well known that folic acid supplementation decreases about 70% of all NTDs, although the mechanism by which this occurs is still relatively unknown. The current theory is that folic acid deficiency ultimately leads to depletion of the methyl pool, leaving critical genes unmethylated, and, in turn, their improper expression leads to failure of normal neural tube development. Recently, new studies in human cell lines have shown that folic acid deficiency and DNA hypomethylation can lead to misexpression of microRNAs (miRNAs). Misexpression of critical miRNAs during neural development may lead to a subtle effect on neural gene regulation, causing the sometimes mild to severely debilitating range of phenotypes exhibited in NTDs. This review seeks to cohesively integrate current information regarding folic acid deficiency, methylation cycles, neural development, and miRNAs to propose a potential model of NTD formation. In addition, we have examined the relevant gene pathways and miRNAs that are predicted to affect them, and based on our investigation, we have devised a basic template of experiments for exploring the idea that miRNA misregulation may be linked to folic acid deficiency and NTDs. genesis 48:282–294, 2010. © 2010 Wiley‐Liss, Inc.
Unbound DHA causes a high blank value in β‐oxidation assay: a concern for in vitro studies
Authors: Du Zhen‐Yu , Araujo Pedro , Stubhaug Ingunn , Frøyland Livar 
Published: March 2010

AbstractThe information on binding capacity of different fatty acids (FAs) to albumin is incomplete, however, in the majority of in vitro experiments, FAs and albumin were simply mixed and their affinity believed to be complete. In this study, seven [1‐14C] FAs were mixed with albumin and assayed for β‐oxidation in rat liver homogenates. In the process of identifying the radioactive background of control assay by LCMS/MS, the results indicated different binding capacity of FAs to albumin. The percentage of unbound FAs recovered in clarified acidic solution was lower than 2% with 16:0 and 18:1n‐9, nearly 5% with EPA, 7% with 18:2n‐6, 18:3n‐3 and 20:4n‐6, and surprisingly high to 41% with DHA. Various FA/albumin molar ratios as well as different types of albumin only marginally affected these data. Thus, the big mass of unbound free DHA led to a high blank value, which is 60 times higher than the real value in the procedure of β‐oxidation measurement in vitro. In the design of future FA research in vitro, the binding capacity of FA to albumin or other proteins must be considered, especially for DHA research.
Proficiency test on the determination of mineral oil in sunflower oil
Authors: Karasek Lubomir , Wenzl Thomas , Ulberth Franz 
Published: March 2010

AbstractFollowing the discovery of mineral oil contamination of Ukrainian sunflower oil in April 2008, the Institute for Reference Materials and Measurements (IRMM) of the European Commission's Joint Research Centre (JRC) was requested by the Directorate General Health and Consumers (DG SANCO) to organise a proficiency test on the determination of mineral oil in sunflower oil. The aim of this test was to evaluate the comparability of analysis results gained by laboratories in the EU and the Ukraine. The organisation of the study and the evaluation of the results were done in accordance with “The International Harmonised Protocol for the Proficiency Testing of Analytical Chemistry Laboratories” and ISO Guide 43. Altogether 62 laboratories from 19 EU member states, Switzerland and the Ukraine subscribed for participation in the study. Four test samples at concentration levels between about 100 and 350 mg/kg, comprising contaminated crude sunflower oil, contaminated refined sunflower oil, and spiked sunflower oil, and a solution of mineral oil in n‐heptane were dispatched to the participants. The participants were asked to determine the mineral oil content of the test samples by application of their in‐house analysis methods. In total, 55 sets of results were reported to the organisers of the study. The performance of laboratories was expressed by z‐scores for the oil samples and by relative bias for the mineral oil solution in n‐heptane. The percentage of successful laboratories in the determination of the mineral oil content of sunflower oil was for all sunflower oil test materials about 80%.
Influence of stability on the acute toxicity of CdSe/ZnS nanocrystals to Daphnia magna
Authors: Pace Heather E. , Lesher Emily K. , Ranville James F. 
Published: March 2010

Abstract
The acute toxicity of polymer-coated CdSe/ZnS quantum dots (QDs) to Daphnia magna was investigated using 48-h exposure studies. The principal objective was to relate the toxicity of QDs to specific physical and chemical aspects of the QD. As such, two different CdSe core diameters, 2 nm QDs (green-emitting) and 5 nm QDs (red-emitting), and two different surface coatings, polyethylene oxide (PEO) and 11-mercaptoundecanoic acid (MUA) were studied. The QDs were characterized before and after the 48-h exposure using fluorescence, ultrafiltrations (3 kDa), and inductively coupled plasma-atomic emission spectrometry (ICP-AES) metal analysis. In addition, flow field flow fractionation-inductively coupled plasma-mass spectrometry (Fl FFF-ICP-MS) was used as a more extensive characterization technique to determine particle size and composition as well as identify other potential constituents in the QD solutions. The more stable QDs (PEO) were found to be less acutely toxic than the QDs with accelerated dissolution (MUA), suggesting QD stability has significant impact on the nanoparticles' short-term toxicity. The emergence of dissolved Cd2+ in solution indicates that the toxicity of the MUA QDs is likely due to Cd poisoning, and a mass-based dose response occurred as a consequence of this mode of action. Alternatively, the PEO QDs caused acute toxicity without observed particle dissolution (i.e., no detectable metals were solubilized), suggesting an alternative mode of toxic action for these nanoparticles. Results of the present study suggest that using particle number, instead of mass, as a dose metric for the PEO QDs, produces markedly different conclusions, in that smaller core size does not equate to greater toxicity. Environ. Toxicol. Chem. 2010;29:1338–1344. © 2010 SETAC
Quick assessment of cytotoxins effect on Daphnia magna using in vivo fluorescence microscopy
Authors: Teplova Vera V. , Andreeva-Kovalevskaya Zhanna I. , Sineva Elena V. , Solonin Alexander S. 
Published: March 2010

Abstract
A novel approach to contaminant toxicity screening is proposed. The use of fluorescent microscopy with fluorescent dyes allows for assessing intoxication of Daphnia magna tissues, at various stages of exposure, to contaminants present in water. As shown, D. magna may not only be used as a test species in toxicity tests based on its lethality, but due to its translucency and application of fluorescent probes, separate steps of its intoxication and dying can be visualized. Using a variety of fluorescent probes, the present study also contributes to a better understanding of the toxicity mechanisms. Environ. Toxicol. Chem. 2010;29:1345–1348. © 2010 SETAC
A highly automated parallel Chimera method for overset grids based on the implicit hole cutting technique
Authors: Landmann B. , Montagnac M. 
Published: March 2010

AbstractA parallel automated Chimera overset grid algorithm for complex configurations is presented in this paper. The algorithm is based on the implicit hole cutting (IHC) algorithm presented by Lee and Baeder, which is enhanced by several methodologies to eliminate shortcomings in the original method. The resulting overall algorithm is more general than the IHC algorithm, while preserving the high degree of automation of the original method.The approach is well suited for handling steady flow problems. The effectiveness of the presented method is demonstrated with several aerodynamic test cases. Copyright © 2010 John Wiley & Sons, Ltd.
Spectral element analysis of herringbone‐grooved journal bearings with groove–ridge discontinuity
Authors: Chen Chien‐Yu , Yen Ruey‐Hor , Chang Chia‐Chin 
Published: March 2010

AbstractMany researchers have investigated the performance of herringbone‐grooved journal bearings (HGJBs). However, few have yet mentioned the issue of film thickness discontinuities in HGJBs with a finite number of grooves. Most studies have involved the application of a finite difference method for discretization. The present work utilizes the spectral element method to calculate the pressure distribution and dynamic coefficients of HGJBs, in which the thickness of the fluid film changes abruptly in the groove–ridge region. Conservation of mass is adopted to solve the problem. Additionally, the present method can be adopted for grooves with curvy geometry. The numerical results were compared with the analytical solution for a one‐dimensional slider bearing and an HGJB. It also shows that for the case of HGJB, the numerical result by the present method is more accurate than the numerical results found in the literature (Trans. ASME J. Tribol. 2000; 122: 103–109, Int. J. Numer. Meth. Heat Fluid Flow 2002; 12: 518–540). Furthermore, employing the present method with the Elrod algorithm can improve the accuracy of deriving loads of HGJBs when cavitation occurs.In addition, the result displays the efficiency of the present method by observing the CPU time. Therefore, the approach can be employed to compute the critical mass of a HGJB. The influence of changing groove angle, groove depth, groove width, and the eccentricity on the critical mass are discussed. Observing the variations in critical mass shows that when the eccentricity is small, a larger groove angle, a lower groove depth, and smaller groove width correspond to a higher critical mass of the HGJB. Copyright © 2010 John Wiley & Sons, Ltd.
Multivariate padé approximation for solving partial differential equations (PDE)
Authors: Turut Veyis , Çelik Ercan , Yiğider Muhammed 
Published: March 2010

AbstractIn this paper, numerical solution of partial differential equations (PDEs) is considered by multivariate padé approximations. We applied these method to two examples. First, PDE has been converted to power series by two‐dimensional differential transformation, Then the numerical solution of equation was put into multivariate padé series form. Thus, we obtained numerical solution of PDE. Copyright © 2010 John Wiley & Sons, Ltd.
Incorporating linguistic, probabilistic, and possibilistic information in a risk-based approach for ranking contaminated sites
Authors: Zhang Kejiang , Achari Gopal , Pei Yuansheng 
Published: March 2010

Abstract
Different types of uncertain information—linguistic, probabilistic, and possibilistic—exist in site characterization. Their representation and propagation significantly influence the management of contaminated sites. In the absence of a framework with which to properly represent and integrate these quantitative and qualitative inputs together, decision makers cannot fully take advantage of the available and necessary information to identify all the plausible alternatives. A systematic methodology was developed in the present work to incorporate linguistic, probabilistic, and possibilistic information into the Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE), a subgroup of Multi-Criteria Decision Analysis (MCDA) methods for ranking contaminated sites. The identification of criteria based on the paradigm of comparative risk assessment provides a rationale for risk-based prioritization. Uncertain linguistic, probabilistic, and possibilistic information identified in characterizing contaminated sites can be properly represented as numerical values, intervals, probability distributions, and fuzzy sets or possibility distributions, and linguistic variables according to their nature. These different kinds of representation are first transformed into a 2-tuple linguistic representation domain. The propagation of hybrid uncertainties is then carried out in the same domain. This methodology can use the original site information directly as much as possible. The case study shows that this systematic methodology provides more reasonable results. Integr Environ Assess Manag 2010;6:711–724. © 2010 SETAC