Sample records for toxicity characteristic teaching

  1. Teacher Characteristics and Students' Choice of Teaching as a ...

    African Journals Online (AJOL)

    Teacher Characteristics and Students' Choice of Teaching as a Career in Osun ... the teacher characteristics that influence students' choice of teaching as a career ... The result revealed that factors such as quality of teaching, mode of dressing ...

  2. Characteristics of medical teachers using student-centered teaching methods. (United States)

    Kim, Kyong-Jee; Hwang, Jee-Young


    This study investigated characteristics of medical teachers who have adopted student-centered teaching methods into their teaching. A 24-item questionnaire consisted of respondent backgrounds, his or her use of student-centered teaching methods, and awareness of the school's educational objectives and curricular principles was administered of faculty members at a private medical school in Korea. Descriptive statistics and chi-square analysis were conducted to compare faculty use of student-centered approaches across different backgrounds and awareness of curricular principles. Overall response rate was 70% (N=140/200), approximately 25% (n=34) of whom were using student-centered teaching methods. Distributions in the faculty use of student-centered teaching methods were significantly higher among basic sciences faculty (versus clinical sciences faculty), with teaching experiences of over 10 years (versus less than 10 years), and who were aware of the school's educational objectives and curricular principles. Our study indicates differences in medical faculty's practice of student-centered teaching across disciplines, teaching experiences, and their understanding of the school's educational objectives curricular principles. These findings have implications for faculty development and institutional support to better promote faculty use of student-centered teaching approaches.

  3. 40 CFR 268.32 - Waste specific prohibitions-Soils exhibiting the toxicity characteristic for metals and... (United States)


    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Waste specific prohibitions-Soils... Prohibitions on Land Disposal § 268.32 Waste specific prohibitions—Soils exhibiting the toxicity characteristic... from land disposal: any volumes of soil exhibiting the toxicity characteristic solely because of the...

  4. Architectural space characteristics facilitating teaching and apprenticeship

    Directory of Open Access Journals (Sweden)

    Maria do Carmo de Lima Bezerra


    Full Text Available The article discusses the relevance of the architectural space as a facilitator of teaching and learning processes. It adopts an analytical methodology based on the architecture and pedagogy literature to know the view of these areas on the subject, and identifies relevant spatial attributes to facilitate education. Research has shown that there are recurrences pointing disciplinary fields of environmental comfort, ergonomics and environmental psychology, which were the subject of this conceptual research about the positive and negative impacts on the school design facility by each attribute of these disciplines. As result, it presents a framework of attributes, characteristics and relevance to teaching and learning to be used as support to the space needs assessment, ie: during the first stage of an architectural design process.

  5. The Relationship Among Teaching Methods, Student Characteristics, and Student Involvement in Learning (United States)

    Anderson, Lorin W.; Soctt, Corinne C.


    Individual students tend to benefit differently from different teaching methods; however, when little or nothing is known of the entering students' characteristics regarding learning involvement, the high school teacher would be wise to use the classroom discourse method of teaching. (JD)

  6. Characteristics of mathematics teaching in Shanghai, China: Through the lens of a Malaysian (United States)

    Lim, Chap Sam


    The mathematical performance of Chinese students, from mainland China, Hong Kong and Taiwan, is widely acclaimed in international comparisons of mathematics achievement. However, in the eyes of the Western educators, the environments established in Chinese schools are deemed relatively unfavourable for mathematics learning. This paper reports on a study that investigates the characteristics of effective mathematics teaching in five Shanghai schools. Findings reveal that those characteristics include (a) teaching with variation; (b) emphasis of precise and elegant mathematical language; (c) emphasis of logical reasoning, mathematical thinking and proofing during teaching; (d) order and serious classroom discipline; (e) strong and coherence teacher-student rapport, and (f) strong collaborative culture amongst mathematics teachers.

  7. Teachers' conceptions of learning and teaching in student-centred medical curricula: the impact of context and personal characteristics. (United States)

    Jacobs, Johanna C G; van Luijk, Scheltus J; van der Vleuten, Cees P M; Kusurkar, Rashmi A; Croiset, Gerda; Scheele, Fedde


    Gibbs and Coffey (2004) have reported that teaching practices are influenced by teachers' conceptions of learning and teaching. In our previous research we found significant differences between teachers' conceptions in two medical schools with student-centred education. Medical school was the most important predictor, next to discipline, gender and teaching experience. Our research questions for the current study are (1) which specific elements of medical school explain the effect of medical school on teachers' conceptions of learning and teaching? How? and (2) which contextual and personal characteristics are related to conceptions of learning and teaching? How? Individual interviews were conducted with 13 teachers of the undergraduate curricula in two medical schools. Previously their conceptions of learning and teaching were assessed with the COLT questionnaire. We investigated the meanings they attached to context and personal characteristics, in relation to their conceptions of learning and teaching. We used a template analysis. Large individual differences existed between teachers. Characteristics mentioned at the medical school and curriculum level were 'curriculum tradition', 'support by educational department' and 'management and finances'. Other contextual characteristics were 'leadership style' at all levels but especially of department chairs, 'affordances and support', 'support and relatedness', and 'students' characteristics'. Personal characteristics were 'agency', 'experience with PBL (as a student or a teacher)','personal development', 'motivation and work engagement'and 'high content expertise'. Several context and personal characteristics associated with teachers' conceptions were identified, enabling a broader view on faculty development with attention for these characteristics, next to teaching skills.

  8. Individual class evaluation and effective teaching characteristics in integrated curricula. (United States)

    Hwang, Jung Eun; Kim, Na Jin; Song, Meiying; Cui, Yinji; Kim, Eun Ju; Park, In Ae; Lee, Hye In; Gong, Hye Jin; Kim, Su Young


    In an integrated curriculum, multiple instructors take part in a course in the form of team teaching. Accordingly, medical schools strive to manage each course run by numerous instructors. As part of the curriculum management, course evaluation is conducted, but a single, retrospective course evaluation does not comprehensively capture student perception of classes by different instructors. This study aimed to demonstrate the need for individual class evaluation, and further to identify teaching characteristics that instructors need to keep in mind when preparing classes. From 2014 to 2015, students at one medical school left comments on evaluation forms after each class. Courses were also assessed after each course. Their comments were categorized by connotation (positive or negative) and by subject. Within each subject category, test scores were compared between positively and negatively mentioned classes. The Mann-Whitney U test was performed to test group differences in scores. The same method was applied to the course evaluation data. Test results for course evaluation showed group difference only in the practice/participation category. However, test results for individual class evaluation showed group differences in six categories: difficulty, main points, attitude, media/contents, interest, and materials. That is, the test scores of classes positively mentioned in six domains were significantly higher than those of negatively mentioned classes. It was proved that individual class evaluation is needed to manage multi-instructor courses in integrated curricula of medical schools. Based on the students' extensive feedback, we identified teaching characteristics statistically related to academic achievement. School authorities can utilize these findings to encourage instructors to develop effective teaching characteristics in class preparation.

  9. Adult Student Preferences: Instructor Characteristics Conducive to Successful Teaching (United States)

    Phillips, Lindsay A.; Baltzer, Carolyn; Filoon, Lisa; Whitley, Cynthia


    Purpose: This study examined adult students' perspectives on what characteristics make for successful teaching and learning environments in the adult student classroom. Methodology: One hundred and thirty-two adult students (ranging in age from 22 to 70) participated in a mixed methods (quantitative and qualitative) survey. Findings: Adult…

  10. Associations between teaching effectiveness scores and characteristics of presentations in hospital medicine continuing education. (United States)

    Ratelle, John T; Wittich, Christopher M; Yu, Roger C; Newman, James S; Jenkins, Sarah M; Beckman, Thomas J


    There is little research regarding characteristics of effective continuing medical education (CME) presentations in hospital medicine (HM). Therefore, we sought to identify associations between validated CME teaching effectiveness scores and characteristics of CME presentations in the field of HM. This was a cross-sectional study of participants and didactic presentations from a national HM CME course in 2014. Participants provided CME teaching effectiveness (CMETE) ratings using an instrument with known validity evidence. Overall CMETE scores (5-point scale: 1 = strongly disagree; 5 = strongly agree) were averaged for each presentation, and associations between scores and presentation characteristics were determined using the Kruskal-Wallis test. The threshold for statistical significance was set at P teaching effectiveness scores and characteristics of effective CME presentations in HM. Our findings, which support previous research in other fields, indicate that CME presentations may be improved by increasing interactivity through the use of audience response systems and allowing longer presentations. © 2015 Society of Hospital Medicine.

  11. The effects of characteristics of substituents on toxicity of the nitroaromatics: HiT QSAR study (United States)

    Kuz'min, Victor E.; Muratov, Eugene N.; Artemenko, Anatoly G.; Gorb, Leonid; Qasim, Mohammad; Leszczynski, Jerzy


    The present study applies the Hierarchical Technology for Quantitative Structure-Activity Relationships (HiT QSAR) for (i) evaluation of the influence of the characteristics of 28 nitroaromatic compounds (some of which belong to a widely known class of explosives) as to their toxicity; (ii) prediction of toxicity for new nitroaromatic derivatives; (iii) analysis of the effects of substituents in nitroaromatic compounds on their toxicity in vivo. The 50% lethal dose concentration for rats (LD50) was used to develop the QSAR models based on simplex representation of molecular structure. The preliminary 1D QSAR results show that even the information on the composition of molecules reveals the main tendencies of changes in toxicity. The statistic characteristics for partial least squares 2D QSAR models are quite satisfactory ( R 2 = 0.96-0.98; Q 2 = 0.91-0.93; R 2 test = 0.89-0.92), which allows us to carry out the prediction of activity for 41 novel compounds designed by the application of new combinations of substituents represented in the training set. The comprehensive analysis of toxicity changes as a function of substituent position and nature was carried out. Molecular fragments that promote and interfere with toxicity were defined on the basis of the obtained models. It was shown that the mutual influence of substituents in the benzene ring plays a crucial role regarding toxicity. The influence of different substituents on toxicity can be mediated via different C-H fragments of the aromatic ring.

  12. Some Unique Characteristics of Television and Some Implications for Teaching and Learning. (United States)

    Bates, A. W.


    Argues that television has unique educational characteristics that separate it from other media and have implications for teaching and learning. Discussion of distributional and social, control, and symbolic (audiovisual) characteristics is based on published surveys and on research carried out at the Open University. Thirteen references are…

  13. [Healthy eating according to teenagers: perceptions, barriers, and expected characteristics of teaching materials]. (United States)

    Toral, Natacha; Conti, Maria Aparecida; Slater, Betzabeth


    The aim of this study was to evaluate perceptions, barriers, and characteristics of teaching materials to promote healthy eating, as described by teenagers. Four focus groups were conducted with 25 adolescents, including questions on: perceptions regarding diet and motivations to change; concepts of (and barriers to) healthy eating; and characteristics needed for teaching materials to promote healthy eating. The teens were often undecided when attempting to classify a diet as healthy. They generally reported feeling insecure about making dietary changes, but showed adequate notions of healthy eating. The main barriers involved personal and social characteristics: temptation, food flavors, parental influence, and lack of time and options for healthy snacks at school. According to these teenagers, educational materials for promotion of healthy eating should emphasize the immediate benefits and emphasize high-impact messages on the health risks of unhealthy diet.



    characteristics of a toxic leader , but labels the characteristics - leader types.  Deceptive  Autocratic  Egotistic  Incompetent  Ignorant...3 Characteristics of a Toxic Leader ...5 Table 2: Toxic Leader Characteristics

  15. perception of indonesian nursing students regaring caring behavior and teaching characteristics of their clinical nursing instructors

    Directory of Open Access Journals (Sweden)

    madiha mukhtar


    Full Text Available Student’s learning and performance reflects the professional attitude, behavior, ethics and standards of their instructors. The aim of this study is to analyse the perception of Indonesian Nursing students regarding caring behavior and teaching characteristics of their CNIs. In this exploratory cross-sectional study, 149 Professional Nursing students from Regular program (Baccalaureate and Post diploma BSN and 15 Clinical Nursing Instructors were recruited from nursing faculty of public university located in Surabaya Indonesia. Data were collected by questionnaire and FGD was conducted to explore detailed information. In descriptive analysis: 6 % students perceived the caring behavior of their clinical instructors as low, 52.3% responds it as enough and 41.6 % considered it good. Teaching characteristics of CNI; 2.7% low, 26.8 as enough and 70.5 % good as perceived by their students. Data collected from students was analysed by using logistic regression test. Professional commitment with (P-value .038, motivation (P-value .010 and clinical placement environment (P-value .002 in main category (significance value is < 0.05 shows influence on perception of Indonesian nursing students regarding caring behaviour and teaching characteristics of their CNIs. In focused group discussion students’ recommended to increase the number of visits in clinical area and emphasises on bed side clinical demonstration. It can be concluded that students’ characteristics does have influence on their perception regarding caring behavior and clinical setting environment influence their perception regarding teaching characteristics of their CNIs.

  16. Evaluation of genetic diversity between toxic and non toxic Jatropha ...

    African Journals Online (AJOL)


    Indian varieties and a non-toxic variety of Mexican origin by means of about 400 RAPD ... evaluate the level of polymorphism and the capacity to discriminate between the ..... Population genetic software for teaching and research. Mol. Ecol.

  17. Finite difference methods for reducing numerical diffusion in TEACH-type calculations. [Teaching Elliptic Axisymmetric Characteristics Heuristically (United States)

    Syed, S. A.; Chiappetta, L. M.


    A methodological evaluation for two-finite differencing schemes for computer-aided gas turbine design is presented. The two computational schemes include; a Bounded Skewed Finite Differencing Scheme (BSUDS); and a Quadratic Upwind Differencing Scheme (QSDS). In the evaluation, the derivations of the schemes were incorporated into two-dimensional and three-dimensional versions of the Teaching Axisymmetric Characteristics Heuristically (TEACH) computer code. Assessments were made according to performance criteria for the solution of problems of turbulent, laminar, and coannular turbulent flow. The specific performance criteria used in the evaluation were simplicity, accuracy, and computational economy. It is found that the BSUDS scheme performed better with respect to the criteria than the QUDS. Some of the reasons for the more successful performance BSUDS are discussed.

  18. 'You need to have some guts to teach': Teacher preparation and characteristics for the teaching of sexuality and HIV/AIDS education in South African schools. (United States)

    Francis, Dennis A; DePalma, Renée


    Using in-depth interviews, we asked sexuality educators in South Africa about their own professional preparation and what they believed were necessary educator characteristics for teaching Sexuality Education. Our findings show that our teachers taught Sexuality Education without any appropriate qualification or preparation, but because they had a lighter teaching load and had room to take on more teaching hours. Nevertheless, they all mention that 'not anybody can teach Sexuality Education'. Drawing on Shulman's taxonomy of knowledge and Freire's concept of critical consciousness, we attempt to make meaning of the teachers' responses and their relevance for the teaching of Sexuality Education.

  19. Teacher characteristics and teaching styles as effectiveness enhancing factors of classroom practice

    NARCIS (Netherlands)

    Opdenakker, MC; Van Damme, J

    This study examined effects of teacher characteristics (gender, teacher education and certification, class management skills and job satisfaction) and teaching styles on indicators of good classroom practice in mathematics classes in secondary education by means of multilevel analysis. The study


    Directory of Open Access Journals (Sweden)

    Eduard Kolesár


    Full Text Available The amount of cyanogenic glycosides, as natural plant toxicants, in plants varies with plant species and environmental effects. Cyanogenic glycoside as an amygdalin was detected in apricot kernels, bitter almonds and peach, plum, pear and apple seeds. Amygdalin itself is non-toxic, but its HCN production decomposed by some enzymes is toxic substance. Target of this review was to describe the characteristic, metabolism and possible effects of amygdalin on reproductive processes. Previous studies describe the effects of natural compound amygdalin on female and male reproductive systems focused on process of steroidogenesis, spermatozoa motility and morphological abnormalities of spermatozoa. In accordance to the previous studies on amygdalin its benefit is controversial.

  1. Collective student characteristics alter the effects of teaching practices on academic outcomes

    NARCIS (Netherlands)

    Kikas, Eve; Peets, Kätlin; Hodges, Ernest V E


    The goal of this study was to examine the influence of collective student characteristics (academic skills and task persistence at the beginning of first grade) and different teaching practices (child-centered, teacher-directed, and child-dominated) on the development of academic skills and task

  2. Teachers ‘And Students ‘View Points about the Characteristics of Effective Teaching, Brijand University of Medical Sciences and Health Services, April2003-4

    Directory of Open Access Journals (Sweden)

    reza Ghaderi


    Full Text Available Background and purpose: As achieving the intended goals in medical education necessitates the utilization of effective teaching & learning methods. In order to further retention of the knowledge, continuous research is needed to study the factors affecting the quantitative and qualitative development of medical education. This study was to recognize the factors delineated by the students and teachers as to be important in the teaching-learning process.Methods: this was a cross-sectional descriptive-analytic study comprised of 880 students and 68 teachers at the Medical University of Birjand, lasting from April 2003 till April 2004. SPSS software and statistical test of Mann-Whitney were used for data analysis.Results: In this study, teachers ‘and students’ opinions about the characteristics of an effective teaching includingProfessional, and personal characteristics of the teachers, and motivation students toward independent learning each consisting of several items - were assessed  with regard to their sex, marital status. Residential status, educational level and educational group.The results were as the followings: Professional characteristics of the teachers: mastery over the subject. Rational sequencing of the subject matters, proper use of the basic knowledge of the related discipline, and use of simple language in teaching, were the choices rated by the teachers and students as the most important ones. Personal characteristics of teachers: self confidence in teaching. Interests in teaching, clear speech were the choices most rated by the teachers and students.Amongst the 3 characteristics of an effective teaching, teachers gave the first priority to motivation the students toward independent learning. While students regarded the professional characteristics of the teachers as the most preferred one.Conclusion: The study found that teachers and students regarded mastery over the subject, self confidence in teaching, use of simple

  3. Activating teaching methods in french language teaching


    Kulhánková, Anna


    The subject of this diploma thesis is activating teaching methods in french language teaching. This thesis outlines the issues acitvating teaching methods in the concept of other teaching methods. There is a definition of teaching method, classification of teaching methods and characteristics of each activating method. In the practical part of this work are given concrete forms of activating teaching methods appropriate for teaching of french language.

  4. The Influence of Soil Characteristics on the Toxicity of Oil Refinery Waste for the Springtail Folsomia candida (Collembola). (United States)

    Reinecke, Adriaan J; van Wyk, Mia; Reinecke, Sophie A


    We determined the toxicity of oil refinery waste in three soils using the springtail Folsomia candida (Collembola) in bioassays. Sublethal exposure to a concentration series of API-sludge presented EC50's for reproduction of 210 mg/kg in site soil; 880 mg/kg in LUFA2.2- and 3260 mg/kg in OECD-soil. The sludge was the least toxic in the OECD-soil with the highest clay and organic matter content, the highest maximum water holding capacity, and the least amount of sand. It was the most toxic in the reference site soil with the lowest organic matter content and highest sand content. The results emphasized the important role of soil characteristics such as texture and organic matter content in influencing toxicity, possibly by affecting bioavailability of toxicants.

  5. Recontextualising Cellular Respiration in Upper Secondary Biology Education. Characteristics and Practicability of a Learning and Teaching Strategy (United States)

    Wierdsma, Menno; Knippels, Marie-Christine; van Oers, Bert; Boersma, Kerst


    Since concepts may have different meanings in different contexts, students have to learn to recontextualise them, i.e. to adapt their meanings to a new context. It is unclear, however, what characteristics a learning and teaching strategy for recontextualising should have. The study aims to develop such a learning and teaching strategy for…

  6. Teaching Motivations, Characteristics and Professional Growth: Results from the Great Expectations (GE) Programme in the United States (United States)

    Thomson, Margareta Maria; Turner, Jeannine


    This present study sought to explore reasons given by K-12 teachers about their motivation to remain in teaching, their motivation for engaging in professional development, and characteristics of their teaching. Participants (N = 151) were public teachers of different grade levels from the USA enrolled in a one-week professional development…

  7. Toxicity of Lanthanum to Pathogenic Fungi and Its Morphological Characteristics

    Institute of Scientific and Technical Information of China (English)


    The inhibitory effects of La on the mycelial growth of several soil-borne pathogenic fungi including Rhizoctonia solani , Pythium sp . , Fusarium solani , Selerotinia sclerotiorum , and Fusarium oxyspoxum were studied in vitro. The results show that the mycelial growth was inhibited strongly by the La, with EC50 of 130 ~ 320 mg· L-1 and EC95 of about 550 ~ 40007 mg· L- 1 respectively. In addition, the morphological toxicity of La was studied by using the scanning electronic microscope. Treated by La, the mycelial growth of pathogenic fungi was significantly restrained, and the morphological characteristics were found to be abnormal, such as increased ramification, malformation, partial swelling and shrinking, and irregularly entangled mycelial block or rhizomorph.

  8. Categorization of nano-structured titanium dioxide according to physicochemical characteristics and pulmonary toxicity

    Directory of Open Access Journals (Sweden)

    Naoki Hashizume

    Full Text Available A potentially useful means of predicting the pulmonary risk posed by new forms of nano-structured titanium dioxide (nano-TiO2 is to use the associations between the physicochemical properties and pulmonary toxicity of characterized forms of TiO2. In the present study, we conducted intratracheal administration studies in rats to clarify the associations between the physicochemical characteristics of seven characterized forms of TiO2 and their acute or subacute pulmonary inflammatory toxicity. Examination of the associations between the physicochemical characteristics of the TiO2 and the pulmonary inflammatory responses they induced revealed (1 that differences in the crystallinity or shape of the TiO2 particles were not associated with the acute pulmonary inflammatory response; (2 that particle size was associated with the acute pulmonary inflammatory response; and (3 that TiO2 particles coated with Al(OH3 induced a greater pulmonary inflammatory response than did non-coated particles. We separated the seven TiO2 into two groups: a group containing the six TiO2 with no surface coating and a group containing the one TiO2 with a surface coating. Intratracheal administration to rats of TiO2 from the first group (i.e., non-coated TiO2 induced only acute pulmonary inflammatory responses, and within this group, the acute pulmonary inflammatory response was equivalent when the particle size was the same, regardless of crystallinity or shape. In contrast, intratracheal administration to rats of the TiO2 from the second group (i.e., the coated TiO2 induced a more severe, subacute pulmonary inflammatory response compared with that produced by the non-coated TiO2. Since alteration of the pulmonary inflammatory response by surface treatment may depend on the coating material used, the pulmonary toxicities of coated TiO2 need to be further evaluated. Overall, the present results demonstrate that physicochemical properties may be useful for predicting the

  9. Role of Pre-Course Student Characteristics on Student Learning in Interactive Teaching Environments (United States)

    Miller, Kelly Anne

    The goal of this dissertation is to broaden our understanding of interactive teaching strategies, in the context of the introductory physics classroom at the undergraduate level. The dissertation is divided into four main projects, each of which investigates a specific aspect of teaching physics interactively. All four projects look towards improving the effectiveness of interactive teaching by understanding how pre-course student characteristics affect the way students learn interactively. We first discuss lecture demonstrations in the context of an interactive classroom using Peer Instruction. We study the role of predictions in conceptual learning. We examine how students' predictions affect what they report having seen during a demonstration. We also examine how student predictions affect what they recall as the outcome of the demonstration at the end of the semester. We then analyze student response patterns to conceptual questions posed during Peer Instruction. We look at the relationship between a student's tendency to switch their answer and pre-course student characteristics like science self-efficacy. Next we elucidate response timing to conceptual questions posed over the course of the semester, in two introductory physics classes taught using Peer Instruction. We look at the relationship between student response times and student characteristics like pre-course physics knowledge, science self-efficacy and gender. We study response times as a way of gaining insight into students thinking in Peer Instruction environments as well as to improve the implementation of Peer Instruction. Finally, we present work on the role of NB, an online collaborative textbook annotation tool, in a flipped, project based, physics class. We analyze the relationship between students' level of online engagement and traditional learning metrics to understand the effectiveness of NB in the context of flipped classrooms. We also report the results of experiments conducted to

  10. Numerical Simulations of Spread Characteristics of Toxic Cyanide in the Danjiangkou Reservoir in China under the Effects of Dam Cooperation

    Directory of Open Access Journals (Sweden)

    Libin Chen


    Full Text Available Many accidents of releasing toxic pollutants into surface water happen each year in the world. It is believed that dam cooperation can affect flow field in reservoir and then can be applied to avoiding and reducing spread speed of toxic pollutants to drinking water intake mouth. However, few studies investigated the effects of dam cooperation on the spread characteristics of toxic pollutants in reservoir, especially the source reservoir for water diversion with more than one dam. The Danjiangkou Reservoir is the source reservoir of the China’ South-to-North Water Diversion Middle Route Project. The human activities are active within this reservoir basin and cyanide-releasing accident once happened in upstream inflow. In order to simulate the spread characteristics of cyanide in the reservoir in the condition of dam cooperation, a three-dimensional water quality model based on the Environmental Fluid Dynamics Code (EFDC has been built and put into practice. The results indicated that cooperation of two dams of the Danjiangkou Reservoir could be applied to avoiding and reducing the spread speed of toxic cyanide in the reservoir directing to the water intake mouth for water diversions.

  11. Key Competencies and Characteristics for Innovative Teaching among Secondary School Teachers: A Mixed-Methods Research (United States)

    Zhu, Chang; Wang, Di


    This research aims to understand the key competencies and characteristics for innovative teaching as perceived by Chinese secondary teachers. A mixed-methods research was used to investigate secondary teachers' views. First, a qualitative study was conducted with interviews of teachers to understand the perceived key competencies and…

  12. Disciplined Improvisation: Characteristics of Inquiry in Mindfulness-Based Teaching. (United States)

    Crane, Rebecca S; Stanley, Steven; Rooney, Michael; Bartley, Trish; Cooper, Lucinda; Mardula, Jody

    Evidence for the effectiveness of mindfulness-based stress reduction (MBSR) and mindfulness-based cognitive therapy (MBCT) is rapidly growing as interest in this field expands. By contrast, there are few empirical analyses of the pedagogy of MBSR and MBCT. Development of the evidence base concerning the teaching of MBCT or MBSR would support the integrity of the approach in the context of rapid expansion. This paper describes an applied conversation analysis (CA) of the characteristics of inquiry in the MBSR and MBCT teaching process. Audio-recordings of three 8-week MBCT and MBSR classes, with 24, 12, and 6 participants, were transcribed and systematically examined. The study focused on the teacher-led interactive inquiry which takes place in each session after a guided meditation practice. The study describes and analyzes three practices within the inquiry process that can be identified in sequences of talk: turn-taking talk involving questions and reformulations; the development of participant skills in a particular way of describing experience; and talk that constructs intersubjective connection and affiliation within the group. CA enables fine-grained analysis of the interactional work of mindfulness-based inquiry. Inquiry is a process of disciplined improvisation which is both highly specific to the conditions of the moment it took place in and uses repeated and recognizable patterns of interaction.


    Directory of Open Access Journals (Sweden)

    Богдана Лабінська


    Full Text Available The paper investigates the specific characteristics of implementing the combined method in teaching foreign languages in Western Ukraine and in Russia (1918–1939. Preconditions of the origin of the combined method have been ascertained. Teaching language aspects and communicative activities has been analyzed on the basis of curricula, manuals and scientific articles of those times. Comparative studies of foreign language teaching methodology in Ukraine and in Russia have been carried out. Fundamentals of the combined method of teaching foreign languages have been substantiated and peculiarities of their realization in the region under investigation have been formulated.

  14. Research on University Network Teaching Platform (Blackboard in Teaching Management

    Directory of Open Access Journals (Sweden)

    Gou Zhao Xia


    Full Text Available With rapid development of online education; teaching platform based on the network, as a new instructional mode has become a hot topic in online teaching. In this paper, the he teaching situation and existing problems on online was analyzed by comparing the difference between network teaching platform and traditional classroom teaching. Then the strategies of network teaching management and the case, which is focusing on the characteristics of Blackboard with the application of network teaching management was presents.

  15. Shifting the Focus to Student Learning: Characteristics of Effective Teaching Practice As Identified by Experienced Pre-service Faculty Advisors

    Directory of Open Access Journals (Sweden)

    Nancy Maynes


    Full Text Available Cochrane-Smith and Power identify trends in teacher education programs with some relating to heightened teacher accountability for students’ learning. In this paper we provide a model that identifies characteristics believed to be critical elements related to a teacher’s conceptual focus shifting from an emphasis on their teaching to their students’ learning and we have grounded these characteristics in current educational research. Through focus group inquiry, we have identified those teacher characteristics thought to account for effective teaching practice. These characteristics include: a professional growth perspective, passion and enthusiasm for the  content, pedagogical content knowledge, a rich instructional repertoire of strategies, awareness of assessment for, as, and of learning, ability to read the body language  of the learner, caring classroom management strategies, and instructional efforts (e.g., social justice. Our research data provide a conceptual framework for further study.

  16. Atmospheric toxic metals emission inventory and spatial characteristics from anthropogenic sources of Guangdong province, China (United States)

    Cher, S.; Menghua, L.; Xiao, X.; Yuqi, W.; Zhuangmin, Z.; Zhijiong, H.; Cheng, L.; Guanglin, J.; Zibing, Y.; Junyu, Z.


    Atmospheric toxic metals (TMs) are part of particulate matters, and may create adverse effects on the environment and human health depending upon their bioavailability and toxicity. Localized emission inventory is fundamental for parsing of toxic metals to identify key sources in order to formulate efficient toxic metals control strategies. With the use of the latest municipal level environment statistical data, this study developed a bottom-up emission inventory of five toxic metals (Hg, As, Pb, Cd, Cr) from anthropogenic activities in Guangdong province for the year of 2014. Major atmospheric toxic metals sources including combustion sources (coal, oil, biomass, municipal solid waste) and industrial process sources (cement production, nonferrous metal smelting, iron and steel industry, battery and fluorescent lamp production) were investigated. Results showed that: (1) The total emissions of Hg, As, Pb, Cd, Cr in Guangdong province were 18.14, 32.59, 411.34, 13.13, 84.16 t, respectively. (2) Different pollutants have obvious characteristics of emission sources. For total Hg emission, 46% comes from combustion sources, of which 32% from coal combustion and 8% from MSW combustion. Other 54% comes from industrial processes, which dominated by the cement (19%), fluorescent lamp (18%) and battery production (13%). Of the total Hg emission, 69% is released as Hg0 , 29% as Hg2+ , and only 2% as Hgp due to strict particulate matters controls policies. For As emissions, coal combustion, nonferrous metal smelting and iron and steel industry contributed approximate 48%, 25% and 24%, respectively. Pb emissions primarily come from battery production (42%), iron and steel industry (21%) and on-road mobile gasoline combustion (17%). Cd and Cr emissions were dominated by nonferrous metal smelting (71%) and iron and steel industry (82%), respectively. (3) In term of the spatial distribution, emissions of atmospheric toxic metals are mainly concentrated in the central region of

  17. Characteristic vibrational frequencies of toxic polychlorinated dibenzo-dioxins and -furans

    International Nuclear Information System (INIS)

    Patrizi, Barbara; Cumis, Mario Siciliani de; Viciani, Silvia; D’Amato, Francesco; Foggi, Paolo


    Highlights: • Database reporting FT-IR spectra for 13 of the 17 toxic PCDDs and PCDFs congeners. • Use of FT-IR database for quantification of toxic PCDD/Fs in complex matrix. • Monitoring of dioxin emissions from waste incinerators. - Abstract: The possibility to monitor in real-time the emission of dioxins produced by incineration of waste or by industrial processes is nowadays a necessity considering the high toxicity of these compounds, their persistence in the environment and their ability to bio-accumulate in the food chain. Recently it has been demonstrated the potentiality of detecting dioxins in carbon tetrachloride via MIR Quantum Cascade Lasers. A fundamental step in real time monitoring of dioxins emission is the possibility to recognize the most toxic congeners within complex mixtures and at low concentrations. Taking into account the lack of spectroscopic data about these very toxic environmental pollutants and the necessity to monitor their emissions we have recorded infrared spectra of 13 of the 17 most toxic congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) dissolved in carbon tetrachloride. In this way we have obtained a small database that we have used to test the ability of a linear regression algorithm to recognize each congener and its relative concentration in complex mixtures of these compounds

  18. Characteristic vibrational frequencies of toxic polychlorinated dibenzo-dioxins and -furans

    Energy Technology Data Exchange (ETDEWEB)

    Patrizi, Barbara, E-mail: [LENS, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); CNR, Istituto Nazionale di Ottica, Largo Enrico Fermi 6, 50125 Firenze (Italy); Cumis, Mario Siciliani de; Viciani, Silvia; D’Amato, Francesco [CNR, Istituto Nazionale di Ottica, Largo Enrico Fermi 6, 50125 Firenze (Italy); Foggi, Paolo [LENS, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino (Italy); CNR, Istituto Nazionale di Ottica, Largo Enrico Fermi 6, 50125 Firenze (Italy); Università degli Studi di Perugia, Dipartimento di Chimica, Via Elce di Sotto 8, 06123 Perugia (Italy)


    Highlights: • Database reporting FT-IR spectra for 13 of the 17 toxic PCDDs and PCDFs congeners. • Use of FT-IR database for quantification of toxic PCDD/Fs in complex matrix. • Monitoring of dioxin emissions from waste incinerators. - Abstract: The possibility to monitor in real-time the emission of dioxins produced by incineration of waste or by industrial processes is nowadays a necessity considering the high toxicity of these compounds, their persistence in the environment and their ability to bio-accumulate in the food chain. Recently it has been demonstrated the potentiality of detecting dioxins in carbon tetrachloride via MIR Quantum Cascade Lasers. A fundamental step in real time monitoring of dioxins emission is the possibility to recognize the most toxic congeners within complex mixtures and at low concentrations. Taking into account the lack of spectroscopic data about these very toxic environmental pollutants and the necessity to monitor their emissions we have recorded infrared spectra of 13 of the 17 most toxic congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) dissolved in carbon tetrachloride. In this way we have obtained a small database that we have used to test the ability of a linear regression algorithm to recognize each congener and its relative concentration in complex mixtures of these compounds.

  19. Toxic substances alert program (United States)

    Junod, T. L.


    A toxicity profile is provided, of 187 toxic substances procured by NASA Lewis Research Center during a 3 1/2 year period, including 27 known or suspected carcinogens. The goal of the program is to assure that the center's health and safety personnel are aware of the procurement and use of toxic substances and to alert and inform the users of these materials as to the toxic characteristics and the control measures needed to ensure their safe use. The program also provides a continuing record of the toxic substances procured, who procured them, what other toxic substances the user has obtained in the past, and where similar materials have been used elsewhere at the center.

  20. Separations chemistry of toxic metals

    International Nuclear Information System (INIS)

    Smith, P.; Barr, M.; Barrans, R.


    Sequestering and removing toxic metal ions from their surroundings is an increasingly active area of research and is gaining importance in light of current environmental contamination problems both within the DOE complex and externally. One method of separating metal ions is to complex them to a molecule (a ligand or chelator) which exhibits specific binding affinity for a toxic metal, even in the presence of other more benign metals. This approach makes use of the sometimes subtle differences between toxic and non-toxic metals resulting from variations in size, charge and shape. For example, toxic metals such as chromium, arsenic, and technetium exist in the environment as oxyanions, negatively charged species with a characteristic tetrahedral shape. Other toxic metals such as actinides and heavy metals are positively charged spheres with specific affinities for particular donor atoms such as oxygen (for actinides) and nitrogen (for heavy metals). In most cases the toxic metals are found in the presence of much larger quantities of less toxic metals such as sodium, calcium and iron. The selectivity of the chelators is critical to the goal of removing the toxic metals from their less toxic counterparts. The approach was to build a ligand framework that complements the unique characteristics of the toxic metal (size, charge and shape) while minimizing interactions with non-toxic metals. The authors have designed ligands exhibiting specificity for the target metals; they have synthesized, characterized and tested these ligands; and they have shown that they exhibit the proposed selectivity and cooperative binding effects

  1. Hazardous Waste Management System - Identification and Listing of Hazardous Waste - Toxicity Characteristic - Hydrocarbon Recovery Operations - Federal Register Notice, February 1, 1991 (United States)

    Extends the compliance date of the Toxicity Characteristic until January 25, 1991 for groundwater that is reinjected or reinfiltrated during existing hydrocarbon recovery operations at petroleum refineries, marketing terminals, and bulk plants.

  2. Pediatric Toxic Shock Syndrome

    Directory of Open Access Journals (Sweden)

    Jennifer Yee


    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the diagnosis and management of a pediatric patient with toxic shock syndrome. The case is also appropriate for teaching of medical students and advanced practice providers, as well as a review of the principles of crisis resource management, teamwork, and communication. Introduction: Toxic shock syndrome is a low-frequency, high-acuity scenario requiring timely identification and aggressive management. If patients suffering from this condition are managed incorrectly, they may progress into multi-organ dysfunction and potentially death. Toxic shock syndrome has been associated with Streptococcus and Staphylococcus aureus (Staph. Approximately half of Staph cases are associated with menstruation, which was first described in the 1970s-1980s and was associated with the use of absorbent tampons.1 Group A Streptococcus may cause complications such as necrotizing fasciitis and gangrenous myositis.2 Pediatric patients may present critically ill from toxic shock syndrome. Providers need to perform a thorough history and physical exam to discern the source of infection. Management requires aggressive care with antibiotics and IV fluids. Objectives: By the end of this simulation session, the learner will be able to: 1 Recognize toxic shock syndrome. 2 Review the importance of a thorough physical exam. 3 Discuss management of toxic shock syndrome, including supportive care and the difference in antibiotic choices for streptococcal and staphylococcal toxic shock syndrome. 4 Appropriately disposition a patient suffering from toxic shock syndrome. 5 Communicate effectively with team members and nursing staff during a resuscitation of a critically ill patient. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on toxic shock syndrome.

  3. Hazardous Waste Management System - Identification and Listing of Hazardous Waste - Toxicity Characteristic - Hydrocarbon Recovery Operations - Federal Register Notice, April 2, 1991 (United States)

    Proposal to extend the compliance date for the Toxicity Characteristic until January 25, 1993 for produced groundwater from free phase hydrocarbon recovery operations at certain petroleum industry sites-namely, refineries, marketing terminals, bulk plants.

  4. Recontextualising Cellular Respiration in Upper Secondary Biology Education. Characteristics and Practicability of a Learning and Teaching Strategy

    NARCIS (Netherlands)

    Wierdsma, Menno; Knippels, Marie Christine; van Oers, Bert; Boersma, Kerst Th


    Since concepts may have different meanings in different contexts, students have to learn to recontextualise them, i.e. to adapt their meanings to a new context. It is unclear, however, what characteristics a learning and teaching strategy for recontextualising should have. The study aims to develop

  5. Recontextualising cellular respiration in upper secondary biology education: characteristics and practicability of a learning and teaching strategy

    NARCIS (Netherlands)

    Wierdsma, Menno; Knippels, Marie-Christine; Oers, Bert; Boersma, Kerst


    Since concepts may have different meanings in different contexts, students have to learn to recontextualise them, i.e. to adapt their meanings to a new context. It is unclear, however, what characteristics a learning and teaching strategy for recontextualising should have. The study aims to develop

  6. Hazardous Waste Management System - Identification and Listing of Hazardous Waste - Toxicity Characteristic - Hydrocarbon Recovery Operations - Federal Register Notice, October 5, 1990 (United States)

    The Agency is promulgating an interim final rule to extend the compliance date of the Toxicity Characteristic rule for petroleum refining facilities, marketing terminals and bulk plants engaged in the recovery and remediation operation for 120 days.

  7. Application of Toxic Chinese Medicine in Chinese Pharmacopoeia (United States)

    Zhao, Hui; Feng, Yu; Mao, Mingsan


    Objective: Explore the application characteristics of proprietary Chinese medicine prescriptions containing toxic herbs in pharmacopoeia. Methods: In this paper, according to the clinical application of pharmacopoeia proprietary Chinese medicine is divided into table agent, Qushu agent, diarrhea agent, heat agent, Wen Li agent, cough and asthma agents, resuscitation agent, Gutian agent, Fuzheng agent, Anshen agent, hemostatic agent, The traditional Chinese medicine prescription and the clinical application of the Chinese herbal medicine containing the toxic Chinese medicine were analyzed and sorted out., Summed up the compatibility of toxic herbs and application characteristics. Results: Toxic Chinese herbal medicine in the cure of traditional Chinese medicine to play a long-standing role, through the overall thinking, dialectical thinking, and thinking of toxic Chinese medicine in the analysis of Chinese medicine that [2], toxic Chinese medicine in the application of proprietary Chinese medicine can not lack. Conclusion: Pharmacopoeia included proprietary Chinese medicine not only in the clinical treatment of good, but also the application of its toxic traditional Chinese medicine and its understanding of the enrichment of the toxic characteristics of traditional Chinese medicine and treatment-related disease pathology between the points of contact for patients with clinical applications Based on and theoretical guidance of Chinese medicine [3].

  8. Influence of selected water quality characteristics on the toxicity of lambda-cyhalothrin and gamma-cyhalothrin to Hyalella azteca. (United States)

    Smith, S; Lizotte, R E


    This study was conducted to assess the influence of suspended solids, dissolved organic carbon, and phytoplankton (as chlorophyll a) water quality characteristics on lambda-cyhalothrin and gamma-cyhalothrin aqueous toxicity to Hyalella azteca using natural water from 12 ponds and lakes in Mississippi, USA with varying water quality characteristics. H. azteca 48-h immobilization EC50 values ranged from 1.4 to 15.7 ng/L and 0.6 to 13.4 ng/L for lambda-cyhalothrin and gamma-cyhalothrin, respectively. For both pyrethroids, EC50 values linearly increased as turbidity, suspended solids, dissolved organic carbon and chlorophyll a concentrations increased.

  9. From Teaching to Facilitation

    DEFF Research Database (Denmark)

    de Graaff, Erik


    A shift from teaching to learning is characteristic of the introduction of Problem Based Learning (PBL) in an existing school. As a consequence the teaching staff has to be trained in skills like facilitating group work and writing cases. Most importantly a change in thinking about teaching...

  10. Toxicity alarm: Case history

    International Nuclear Information System (INIS)

    Hogan, D.; Retallack, J.


    In late fall 1991, the Novacor petrochemical plant near Joffre, Alberta experienced a toxicity alarm, the first since its startup 14 years ago. Fish exposed to a normal toxicity test were stressed within 2 h and showed 100% mortality after 24 h. A history of the events leading up to, during, and after the toxicity alarm is presented. The major effluent sources were three cooling water systems. Although these sources are well characterized, the event causes were not immediately clear. Initial toxic screening indicated that one was very toxic, another moderately toxic, and the third not toxic at all. All three systems utilized the same chemical treatment program to avoid fouling: stabilized phosphates with minor variants. The most toxic of the cooling systems operated at 10-12 cycles, had three chemicals for biocide control, and had three makeup streams. Toxic and nontoxic system characteristics were compared. An in-depth modified toxicity identification and evaluation program was then performed to identify and evaluate the cause of the toxicity alarm for future prevention. The most probable causes of toxicity were identified by elimination. The combination of high numbers of cycles, hydrocarbons in the makeup water, and bromine added as an antifoulant resulted in formation of aromatic bromamines which are capable of causing the toxic condition experienced. 2 tabs

  11. Toxic Leadership in Educational Organizations (United States)

    Green, James E.


    While research on the traits and skills of effective leaders is plentiful, only recently has the phenomenon of toxic leadership begun to be investigated. This research report focuses on toxic leadership in educational organizations--its prevalence, as well as the characteristics and early indicators. Using mixed methods, the study found four…

  12. Taking the Grading Leniency Story to the Edge. The Influence of Student, Teacher, and Course Characteristics on Student Evaluations of Teaching in Higher Education (United States)

    Brockx, Bert; Spooren, Pieter; Mortelmans, Dimitri


    The use of student evaluation of teaching (SET) to evaluate and improve teaching is widespread amongst institutions of higher education. Many authors have searched for a conclusive understanding about the influence of student, course, and teacher characteristics on SET. One hotly debated discussion concerns the interpretation of the positive and…

  13. Motivation for the teaching profession


    Křížová, Kateřina


    Anotace: The thesis "The motivation for the teaching profession" dealt with fundamental problems of motivation to the teaching profession. In the theoretical part, we have focused on general characteristics of terms that pertain to the teaching profession, particularly the theory of the teaching profession, the choice of the teaching profession, the phase of the teaching profession, teacher typology, the role of teacher training and professionalization of teachers, but also washed into the te...

  14. Expectations Compared of First-Year Students in Pre-School and Primary School Education Degrees at the University of Burgos in Relation to Characteristics and Practices in University Teaching most Desired

    Directory of Open Access Journals (Sweden)



    Full Text Available The intention of this work is to detect and analyse the desired characteristics and teaching practices that first year students will be taught in different subjects, comparing Pre-school with Primary Education degree at Burgos University. For that purpose, we have analysed data obtained from 120 surveys (60 others the Pre-school degree and 60 from the Primary Education degree, the surveys are based on the five basic aspects that we consider fundamental of a university education: personal and professional characteristics, evaluation, tutorial, information and communications technology (ICT and methodologies of education/learning. The results show that the student body values more the professional characteristics of its teaching staff than the personal ones; and the image transmitted by the teaching staff that uses ICT is always positive, creating a favourable opinion of his teaching, and the student body reaches to consider that ICTs are indispensable to nowadays education.

  15. Acute and Sub-chronic (28-day) Oral Toxicity Studies of ...

    African Journals Online (AJOL)


    was to investigate the acute and sub-chronic toxicity of A. conyzoides leaves in Wistar rats. Methods: In the acute test, the ... associated with navel in children [4], and in the treatment of ... Ethical Committee for Teaching and. Research (ref no.

  16. Optimization of Medical Teaching Methods

    Directory of Open Access Journals (Sweden)

    Wang Fei


    Full Text Available In order to achieve the goal of medical education, medicine and adapt to changes in the way doctors work, with the rapid medical teaching methods of modern science and technology must be reformed. Based on the current status of teaching in medical colleges method to analyze the formation and development of medical teaching methods, characteristics, about how to achieve optimal medical teaching methods for medical education teachers and management workers comprehensive and thorough change teaching ideas and teaching concepts provide a theoretical basis.

  17. Chapter 6: Selenium Toxicity to Aquatic Organisms (United States)

    This chapter addresses the characteristics and nature of organic selenium (Se) toxicity to aquatic organisms, based on the most current state of scientific knowledge. As such, the information contained in this chapter relates to the 'toxicity assessment' phase of aquatic ecologi...

  18. Quantitative Methods for Teaching Review


    Irina Milnikova; Tamara Shioshvili


    A new method of quantitative evaluation of teaching processes is elaborated. On the base of scores data, the method permits to evaluate efficiency of teaching within one group of students and comparative teaching efficiency in two or more groups. As basic characteristics of teaching efficiency heterogeneity, stability and total variability indices both for only one group and for comparing different groups are used. The method is easy to use and permits to rank results of teaching review which...

  19. Identification of the mechanisms that drive the toxicity of TiO2 particulates: the contribution of physicochemical characteristics

    Directory of Open Access Journals (Sweden)

    Peters Sheona


    general, requires consideration. At this time it is inappropriate to consider the findings for one TiO2 form as being representative for TiO2 particulates as a whole, due to the vast number of available TiO2 particulate forms and large variety of potential tissue and cell targets that may be affected by exposure. Thus emphasising that the physicochemical characteristics are fundamental to their toxicity.

  20. Study on Case Teaching of Financial Management (United States)

    Che, Zhenghong; Che, Zhengmei


    Case teaching is an efficient teaching method of management. It plays an important role to enhance the students' ability to practice the theory. However, case teaching of financial management has not achieved the expected results. The paper aims to study the importance, characteristics and corresponding methods of case teaching method of financial…

  1. Consumerism and consumer complexity: implications for university teaching and teaching evaluation. (United States)

    Hall, Wendy A


    A contemporary issue is the effects of a corporate production metaphor and consumerism on university education. Efforts by universities to attract students and teaching strategies aimed at 'adult learners' tend to treat student consumers as a homogeneous group with similar expectations. In this paper, I argue that consumer groups are not uniform. I use Dagevos' theoretical approach to categorize consumers as calculating, traditional, unique, and responsible. Based on the characteristics of consumers occupying these categories, I describe the implications of the varying consumer expectations for teaching. I also consider the implications for evaluation of teaching and call for research taking consumer types into account when evaluating teaching. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Support effects in single atom iron catalysts on adsorption characteristics of toxic gases (NO2, NH3, SO3 and H2S) (United States)

    Gao, Zhengyang; Yang, Weijie; Ding, Xunlei; Lv, Gang; Yan, Weiping


    The effects of support on gas adsorption is crucial for single atom catalysts design and optimization. To gain insight into support effects on gas adsorption characteristics, a comprehensive theoretical study was performed to investigate the adsorption characteristics of toxic gases (NO2, NH3, SO3 and H2S) by utilizing single atom iron catalysts with three graphene-based supports. The adsorption geometry, adsorption energy, electronic and magnetic properties of the adsorption system have been explored. Additionally, the support effects have been analyzed through d-band center and Fermi softness, and thermodynamic analysis has been performed to consider the effect of temperature on gas adsorption. The support effects have a remarkable influence on the adsorption characteristics of four types of toxic gases which is determined by the electronic structure of graphene-based support, and the electronic structure can be characterized by Fermi softness of catalysts. Fermi softness and uplift height of Fe atom could be good descriptors for the adsorption activity of single atom iron catalysts with graphene-based supports. The findings can lay a foundation for the further study of graphene-based support effects in single atom catalysts and provide a guideline for development and design of new graphene-based support materials utilizing the idea of Fermi softness.

  3. Modeling Aquatic Toxicity through Chromatographic Systems. (United States)

    Fernández-Pumarega, Alejandro; Amézqueta, Susana; Farré, Sandra; Muñoz-Pascual, Laura; Abraham, Michael H; Fuguet, Elisabet; Rosés, Martí


    Environmental risk assessment requires information about the toxicity of the growing number of chemical products coming from different origins that can contaminate water and become toxicants to aquatic species or other living beings via the trophic chain. Direct toxicity measurements using sensitive aquatic species can be carried out but they may become expensive and ethically questionable. Literature refers to the use of chromatographic measurements that correlate to the toxic effect of a compound over a specific aquatic species as an alternative to get toxicity information. In this work, we have studied the similarity in the response of the toxicity to different species and we have selected eight representative aquatic species (including tadpoles, fish, water fleas, protozoan, and bacteria) with known nonspecific toxicity to chemical substances. Next, we have selected four chromatographic systems offering good perspectives for surrogation of the eight selected aquatic systems, and thus prediction of toxicity from the chromatographic measurement. Then toxicity has been correlated to the chromatographic retention factor. Satisfactory correlation results have been obtained to emulate toxicity in five of the selected aquatic species through some of the chromatographic systems. Other aquatic species with similar characteristics to these five representative ones could also be emulated by using the same chromatographic systems. The final aim of this study is to model chemical products toxicity to aquatic species by means of chromatographic systems to reduce in vivo testing.

  4. Good teaching is good teaching: A narrative review for effective medical educators. (United States)

    Berman, Anthony C


    Educators have tried for many years to define teaching and effective teachers. More specifically, medical educators have tried to define what characteristics are common to successful teachers in the healthcare arena. The goal of teacher educators has long been to determine what makes an effective teacher so that they could do a better job of preparing future teachers to have a positive impact on the learning of their students. Medical educators have explored what makes some of their colleagues more able than others to facilitate the development of healthcare professionals who can successfully and safely meet the needs of future patients. Although there has historically been disagreement regarding the characteristics that need be developed in order for teachers to be effective, educational theorists have consistently agreed that becoming an effective teacher is a complex task. Such discussions have been central to deciding what education at any level is really all about. By exploring the literature and reflecting upon the personal experiences encountered in his lengthy career as a teacher, and as a teacher of teachers, the author reaches the conclusions that teaching is both art and science, that "good teaching is good teaching" regardless of the learning environment or the subject to be explored, and that the characteristics making up an effective medical educator are really not much different than those making up effective educators in any other area. © 2015 American Association of Anatomists.

  5. The reform of the teaching mode of Applied Optics curriculum and analysis of teaching effect (United States)

    Ning, Yu; Xu, Zhongjie; Li, Dun; Chen, Zilun; Cheng, Xiangai; Zhong, Hairong


    Military academies have two distinctive characteristics on talent training: Firstly, we must teach facing actual combat and connecting with academic frontier. Secondly, the bachelor's degree education and the military education should be balanced. The teaching mode of basic curriculum in military academies must be reformed and optimized on the basis of the traditional teaching mode, so as to ensure the high quality of teaching and provide enough guidance and help for students to support their academic burden. In this paper, our main work on "Applied Optics" teaching mode reform is introduced: First of all, we research extensively and learn fully from advanced teaching modes of the well-known universities at home and abroad, a whole design is made for the teaching mode of the core curriculum of optical engineering in our school "Applied Optics", building a new teaching mode which takes the methods of teaching basic parts as details, teaching application parts as emphases, teaching frontier parts as topics and teaching actual combat parts on site. Then combining with the questionnaire survey of students and opinions proposed by relevant experts in the teaching seminar, teaching effect and generalizability of the new teaching mode are analyzed and evaluated.

  6. Studies on the toxic interaction between monensin and tiamulin in rats: toxicity and pathology. (United States)

    Szücs, G; Bajnógel, J; Varga, A; Móra, Z; Laczay, P


    The characteristics of the toxic interaction between monensin and tiamulin were investigated in rats. A three-day comparative oral repeated-dose toxicity study was performed in Phase I, when the effects of monensin and tiamulin were studied separately (monensin 10, 30, and 50 mg/kg or tiamulin 40, 120, and 200 mg/kg body weight, respectively). In Phase II, the two compounds were administered simultaneously to study the toxic interaction (monensin 10 mg/kg and tiamulin 40 mg/kg b.w., respectively). Monensin proved to be toxic to rats at doses of 30 and 50 mg/kg. Tiamulin was well tolerated up to the dose of 200 mg/kg. After combined administration, signs of toxicity were seen (including lethality in females). Monensin caused a dose-dependent cardiotoxic effect and vacuolar degeneration of the skeletal muscles in the animals given 50 mg/kg. Both compounds exerted a toxic effect on the liver in high doses. After simultaneous administration of the two compounds, there was a mild effect on the liver (females only), hydropic degeneration of the myocardium and vacuolar degeneration of the skeletal muscles. The alteration seen in the skeletal muscles was more marked than that seen after the administration of 50 mg/kg monensin alone.

  7. Study on toxicity mutation of crown-vetch induced by radiation

    International Nuclear Information System (INIS)

    Yi Huying; Yu Hongbin; Ma Jianzong


    The suckers of Germany crown-vetch were irradiated by 60 Co gamma ray and fast neutron. The toxicity mutation frequency and genetic stability of crown-vetch were studied. The various toxicity mutants were found in M 1 . Most of the toxicity mutants was unstable in M 2 , Stable mutant was very few (about 2.0-12.9%). β-nitropropionic acid in the low toxicity mutants selected was 31.7-39.8 mg/g. Genetic characteristics of low toxicity mutants were stable in M 3 -M 5

  8. Exploration and practice in-class practice teaching mode (United States)

    Zang, Xue-Ping; Wu, Wei-Feng


    According to the opto-electronic information science and engineering professional course characteristics and cultivate students' learning initiative, raised the teaching of photoelectric professional course introduce In-class practice teaching mode. By designing different In-class practice teaching content, the students' learning interest and learning initiative are improved, deepen students' understanding of course content and enhanced students' team cooperation ability. In-class practice teaching mode in the course of the opto-electronic professional teaching practice, the teaching effect is remarkable.



    generic traits that describe toxic leadership. Broad characteristics of narcissism and cynicism are further reduced to descriptors of selfishness...abuse and tyranny. The persistent abusiveness, authoritarianism, narcissism and unpredictability can be displayed in two categories of toxicity...retention failure to the toxic leadership climate. These leaders are maladjusted, emphasizing narcissism and authoritarianism.25 The primary indicators of

  10. Case study of science teaching in an elementary school: Characteristics of an exemplary science teacher (United States)

    Kao, Huey-Lien

    Improving the quality of science teaching is one of the greatest concerns in recent science education reform efforts. Many science educators suggest that case studies of exemplary science teachers may provide guidance for these reform efforts. For this reason, the characteristics of exemplary science teaching practices have been identified in recent years. However, the literature lacks research exploring exemplary teacher beliefs about the nature of science and science pedagogy, the relationships between their beliefs and practices, or how outstanding teachers overcome difficulties in order to facilitate their students' science learning. In this study, Sam-Yu, an identified exemplary science teacher who teaches in an elementary school in Pintung, Taiwan, was the subject. An interpretative research design (Erickson, 1986) based on principles of naturalistic inquiry (Lincoln & Guba, 1985) was used. Both qualitative and quantitative methods were employed in this case study. The qualitative method involved conducting interviews with the teacher and students, observing classroom activities and analyzing the structure of the learning materials. The quantitative methods involved using the Learning Climate Inventory (LCI) (Lin, 1997) instrument to assess the learning environment of the exemplary science classroom. This study found that Sam-Yu had a blend of views on the nature of science and a varied knowledge about science pedagogy. Personal preferences, past experiences, and the national science curriculum all played important roles in the development and refinement of Sam-Yu's beliefs about science and pedagogy. Regarding his teaching practices, Sam-Yu provided the best learning experiences, as evidenced in both classroom observations and the survey results, for his students by using a variety of strategies. In addition, his classroom behaviors were highly associated with his beliefs about science and pedagogy. However, due to school-based and socio-cultural constraints

  11. New ideas for teaching electrocardiogram interpretation and improving classroom teaching content. (United States)

    Zeng, Rui; Yue, Rong-Zheng; Tan, Chun-Yu; Wang, Qin; Kuang, Pu; Tian, Pan-Wen; Zuo, Chuan


    Interpreting an electrocardiogram (ECG) is not only one of the most important parts of diagnostics but also one of the most difficult areas to teach. Owing to the abstract nature of the basic theoretical knowledge of the ECG, its scattered characteristics, and tedious and difficult-to-remember subject matter, teaching how to interpret ECGs is as difficult for teachers to teach as it is for students to learn. In order to enable medical students to master basic knowledge of ECG interpretation skills in a limited teaching time, we modified the content used for traditional ECG teaching and now propose a new ECG teaching method called the "graphics-sequence memory method." A prospective randomized controlled study was designed to measure the actual effectiveness of ECG learning by students. Two hundred students were randomly placed under a traditional teaching group and an innovative teaching group, with 100 participants in each group. The teachers in the traditional teaching group utilized the traditional teaching outline, whereas the teachers in the innovative teaching group received training in line with the proposed teaching method and syllabus. All the students took an examination in the final semester by analyzing 20 ECGs from real clinical cases and submitted their ECG reports. The average ECG reading time was 32 minutes for the traditional teaching group and 18 minutes for the innovative teaching group. The average ECG accuracy results were 43% for the traditional teaching group and 77% for the innovative teaching group. Learning to accurately interpret ECGs is an important skill in the cardiac discipline, but the ECG's mechanisms are intricate and the content is scattered. Textbooks tend to make the students feel confused owing to the restrictions of the length and the format of the syllabi, apart from many other limitations. The graphics-sequence memory method was found to be a useful method for ECG teaching.

  12. Generational differences of baccalaureate nursing students' preferred teaching methods and faculty use of teaching methods (United States)

    Delahoyde, Theresa

    Nursing education is experiencing a generational phenomenon with student enrollment spanning three generations. Classrooms of the 21st century include the occasional Baby Boomer and a large number of Generation X and Generation Y students. Each of these generations has its own unique set of characteristics that have been shaped by values, trends, behaviors, and events in society. These generational characteristics create vast opportunities to learn, as well as challenges. One such challenge is the use of teaching methods that are congruent with nursing student preferences. Although there is a wide range of studies conducted on student learning styles within the nursing education field, there is little research on the preferred teaching methods of nursing students. The purpose of this quantitative, descriptive study was to compare the preferred teaching methods of multi-generational baccalaureate nursing students with faculty use of teaching methods. The research study included 367 participants; 38 nursing faculty and 329 nursing students from five different colleges within the Midwest region. The results of the two-tailed t-test found four statistically significant findings between Generation X and Y students and their preferred teaching methods including; lecture, listening to the professor lecture versus working in groups; actively participating in group discussion; and the importance of participating in group assignments. The results of the Analysis of Variance (ANOVA) found seventeen statistically significant findings between levels of students (freshmen/sophomores, juniors, & seniors) and their preferred teaching methods. Lecture was found to be the most frequently used teaching method by faculty as well as the most preferred teaching method by students. Overall, the support for a variety of teaching methods was also found in the analysis of data.

  13. Amyloid β42 peptide is toxic to non-neural cells in Drosophila yielding a characteristic metabolite profile and the effect can be suppressed by PI3K

    Directory of Open Access Journals (Sweden)

    Mercedes Arnés


    Full Text Available The human Aβ42 peptide is associated with Alzheimer's disease through its deleterious effects in neurons. Expressing the human peptide in adult Drosophila in a tissue- and time-controlled manner, we show that Aβ42 is also toxic in non-neural cells, neurosecretory and epithelial cell types in particular. This form of toxicity includes the aberrant signaling by Wingless morphogen leading to the eventual activation of Caspase 3. Preventing Caspase 3 activation by means of p53 keeps epithelial cells from elimination but maintains the Aβ42 toxicity yielding more severe deleterious effects to the organism. Metabolic profiling by nuclear magnetic resonance (NMR of adult flies at selected ages post Aβ42 expression onset reveals characteristic changes in metabolites as early markers of the pathological process. All morphological and most metabolic features of Aβ42 toxicity can be suppressed by the joint overexpression of PI3K.

  14. The construction of bilingual teaching of optoelectronic technology (United States)

    Zhang, Yang; Zhao, Enming; Yang, Fan; Li, Qingbo; Zhu, Zheng; Li, Cheng; Sun, Peng


    This paper combines the characteristics of optoelectronic technology with that of bilingual teaching. The course pays attention to integrating theory with practice, and cultivating learners' ability. Reform and exploration have been done in the fields of teaching materials, teaching content, teaching methods, etc. The concrete content mainly includes five parts: selecting teaching materials, establishing teaching syllabus, choosing suitable teaching method, making multimedia courseware and improving the test system, which can arouse students' interest in their study and their autonomous learning ability to provide beneficial references for improving the quality of talents of optoelectronic bilingual courses.

  15. Clinical teaching with emotional intelligence: A teaching toolbox

    Directory of Open Access Journals (Sweden)

    Athar Omid


    Full Text Available Background: Emotional intelligence (EI helps humans to perceive their own and others′ emotions. It helps to make better interpersonal communication that consequently leads to an increase in everyday performance and professional career. Teaching, particularly teaching in the clinical environment, is among the professions that need a high level of EI due to its relevance to human interactions. Materials and Methods: We adopted EI competencies with characteristics of a good clinical teacher. As a result, we extracted 12 strategies and then reviewed the literatures relevant to these strategies. Results: In the present article, 12 strategies that a clinical teacher should follow to use EI in her/his teaching were described. Conclusion: To apply EI in clinical settings, a teacher should consider all the factors that can bring about a more positive emotional environment and social interactions. These factors will increase students′ learning, improve patients′ care, and maintain her/his well-being. In addition, he/she will be able to evaluate her/his teaching to improve its effectiveness.

  16. The Gender-Related Role of Teaching Profession in Turkey (United States)

    Uygun, Selcuk


    Teaching is a professional job that requires expertise. The characteristics of the professionals can affect the quality of the profession. One of these characteristics is gender. In this study, the gender-related role of teaching profession in Turkey is examined. The analysis in a historical perspective of gender distributions of students who have…

  17. Innovative methods in teaching mathematics


    Чепелева, Т. И.


    The report outlines the main directions of innovation in the teaching of higher mathematics at the university. The basic technological approach is suggested when creating lecture presentations such as their color characteristics of fonts, the amount of information on a slide, etc., which is based on teaching experience and is suitable for development of other educational presentations.

  18. Research on teaching methods. (United States)

    Oermann, M H


    studies attempted to identify variables that may influence learning, particularly characteristics of the learner. Only six investigators addressed learning styles and their interactions with the teaching method and outcomes (Gillies, 1984; Goldsmith, 1984; Kirchhoff & Holzemer, 1979; Kissinger & Munjas, 1981; Norris, 1986; Stein et al., 1972). Research in the future needs to focus on the relationship of different learner characteristics, attributes of the teaching method, and learning outcomes. In addition, initial learning, retention, transfer to practice, and instructional time should be studied. Characteristics of the teacher and setting and relationship to the methodologies used and outcomes of instruction need investigation. Research should attempt to identify optimal conditions for learning and ways in which methods should be used for particular students, subject matter, and points in the nursing curriculum...

  19. The SQL Server Database for Non Computer Professional Teaching Reform (United States)

    Liu, Xiangwei


    A summary of the teaching methods of the non-computer professional SQL Server database, analyzes the current situation of the teaching course. According to non computer professional curriculum teaching characteristic, put forward some teaching reform methods, and put it into practice, improve the students' analysis ability, practice ability and…

  20. On English Teaching in Maritime Colleges (United States)

    Shen, Jiang; Wang, Honggui


    According to English level of Chinese ocean sailors at present, we analyze the characteristics and instruction needs of navigation English and point out current English teaching in maritime specialty has many problems. Traditional teaching modes are not suitable for modern maritime needs any longer. So we propose feasible methods and…

  1. From basic physics to mechanisms of toxicity: the ``liquid drop'' approach applied to develop predictive classification models for toxicity of metal oxide nanoparticles (United States)

    Sizochenko, Natalia; Rasulev, Bakhtiyor; Gajewicz, Agnieszka; Kuz'min, Victor; Puzyn, Tomasz; Leszczynski, Jerzy


    Many metal oxide nanoparticles are able to cause persistent stress to live organisms, including humans, when discharged to the environment. To understand the mechanism of metal oxide nanoparticles' toxicity and reduce the number of experiments, the development of predictive toxicity models is important. In this study, performed on a series of nanoparticles, the comparative quantitative-structure activity relationship (nano-QSAR) analyses of their toxicity towards E. coli and HaCaT cells were established. A new approach for representation of nanoparticles' structure is presented. For description of the supramolecular structure of nanoparticles the ``liquid drop'' model was applied. It is expected that a novel, proposed approach could be of general use for predictions related to nanomaterials. In addition, in our study fragmental simplex descriptors and several ligand-metal binding characteristics were calculated. The developed nano-QSAR models were validated and reliably predict the toxicity of all studied metal oxide nanoparticles. Based on the comparative analysis of contributed properties in both models the LDM-based descriptors were revealed to have an almost similar level of contribution to toxicity in both cases, while other parameters (van der Waals interactions, electronegativity and metal-ligand binding characteristics) have unequal contribution levels. In addition, the models developed here suggest different mechanisms of nanotoxicity for these two types of cells.Many metal oxide nanoparticles are able to cause persistent stress to live organisms, including humans, when discharged to the environment. To understand the mechanism of metal oxide nanoparticles' toxicity and reduce the number of experiments, the development of predictive toxicity models is important. In this study, performed on a series of nanoparticles, the comparative quantitative-structure activity relationship (nano-QSAR) analyses of their toxicity towards E. coli and HaCaT cells were


    Directory of Open Access Journals (Sweden)

    A. Arifin


    Full Text Available The purposes of this study are to develop, to test the feasibility, to describe the characteristic, and to test the students understanding about integrated science teaching material about air using Four Steps Teaching Material Development (4S TMD. The Research and Development method was use to develop integrated science teaching materials which is involving  all science perspectives that are not presented in junior high school science book. The air theme was chosen in this study since it can be explained using biology, chemistry, physics, and earth and space science  perspectives. Development the teaching materials was consists of selection, structuring, characterization, and reduction didactic steps. Based on the of feasibility test results, the teaching material is qualified in content, presentation, language, and graphic feasibility aspects. The characteristic of this teaching material expose the closeness theme with student daily lifes and its compatibility with National Books Standard. Based on the understanding test results, the teaching material is qualified in understanding aspect with high category. It can be concluded that the teaching material qualified to be used as supplement teaching material of science learning.Penelitian ini bertujuan untuk mengembangkan, menguji kelayakan, memaparkan karakteristik, dan menguji keterpahaman bahan ajar IPA terpadu pada tema udara untuk siswa SMP kelas VII melalui Four Steps Teaching Material Development (4S TMD. Penelitian dengan metode Research and Development (R&D ini dilatar belakangi oleh tidak tersedianya bahan ajar IPA SMP yang disajikan secara terpadu melalui tema udara. Pengembangan bahan ajar IPA terpadu tema udara terdiri dari tahap seleksi, strukturisasi, karakterisasi dan reduksi didaktik. Berdasarkan uji kelayakan, bahan ajar telah memenuhi aspek kelayakan isi, kelayakan penyajian, kelayakan bahasa dan kelayakan kegrafikan. Karakteristik bahan ajar meliputi kedekatan tema bahan ajar

  3. Üstün Yetenekli Öğrencilerin Öğrenme, Öğretme, Öğretmenlik Mesleği ve Öğretmen Özellikleri ile İlgili Görüşleri (Gifted Students' Perceptions about Learning, Teaching, Teacher Characteristics and Teaching as a Profession

    Directory of Open Access Journals (Sweden)

    Bahadır Erişti


    Full Text Available Purpose and significance: The purpose of the study was to examine gifted students’ attributions to learning and teaching and their views about teacher characteristics and teaching as a profession.Method: This research was a mix of qualitative and quantitative methods. Gifted students' attributions to learning and teaching and their views about teacher charac-teristics and teaching as a profession were portrayed and data was interpreted using quantitative and qualitative methods based on students' own expressions. The re-search was conducted with 46 gifted students who were attending 7th, 8th and 9th grades in Eskisehir, Turkey. Students were identified by the identification system of the Education Programs for Talented Students at Anadolu University in Eskisehir. Students came from 15 different elementary schools; 18 of them were female and 28 were male. Seventeen of the participants were 7th graders, 14 were 8th graders and 15 were 9th graders.Data was collected using “Questionnaire for Gifted Students’ Perceptions of Learn-ing, Teaching and Teacher (QGST” developed by the researcher. It was reviewed by 5 experts in order to examine its content validity. They were professionals in curriculum and instruction, gifted education, and guidance and counseling. After expert revisions, a pilot study was carried out with 21 students before this study. The final form of the instrument included four groups of items. In one item, students ranked 14 teacher characteristics from 1 to 14 in importance with 1 being the most important and 14 the least important. In the other items, of which 4 were open-ended and 7 were forced-choice, students indicated their opinions and choices about learning and teaching. The instrument was administered to the participants during their summer courses they attended at Anadolu University. Data analysis included quantitative and qualitative methods. Quantitative data was analyzed using descriptive non

  4. Toxicity of nonylphenol diethoxylate in lab-scale anaerobic digesters

    DEFF Research Database (Denmark)

    Bozkurt, Hande; Sanin, F. Dilek


    Nonylphenol compounds have high commercial, industrial and domestic uses owing to their surface active properties. In addition to their toxic, carcinogenic and persistent characteristics; they have drawn the attention of scientists lately due to their endocrine disrupting properties....... Their widespread use and disposal cause them to enter wastewater treatment systems at high concentrations. Since they are highly persistent and hydrophobic, they accumulate mostly on sludge.In this study using Anaerobic Toxicity Assay (ATA) tests, the toxicity of a model nonylphenol compound, nonylphenol...

  5. Human health risk assessment based on toxicity characteristic leaching procedure and simple bioaccessibility extraction test of toxic metals in urban street dust of Tianjin, China.

    Directory of Open Access Journals (Sweden)

    Binbin Yu

    Full Text Available The potential ecological and human health risk related with urban street dust from urban areas of Tianjin, China was quantitatively analyzed using the method of toxicity characteristic leaching procedure (TCLP and simple bioaccessibility extraction test (SBET. In the study, Hakason index, Nemerow index (P, the hazard index (HI and the cancer risk index (RI were calculated to assess the potential risk. The sequence of potential ecological risk based on Hakason index was arsenic (As > cadmium (Cd > lead (Pb > copper (Cu > chromium (Cr, in particular, As and Cd were regarded as high polluted metals. While the results of extraction of TCLP were assessed using P, the sequence was As > Pb > Cd > Cr > Cu, which mean that As and Pb should be low polluted, and Cd, Cr and Cu would barely not polluted. For human health, total carcinogenic risk for children and adults was 2.01 × 10(-3 and 1.05 × 10(-3, respectively. This could be considered to be intolerable in urban street dust exposure. The sequence in the hazard quotient (HQ of each element was As > Cr > Pb > Cu > Cd. The HI value of these toxic metals in urban street dust for children and adults was 5.88 × 10(-1 and 2.80 × 10(-1, respectively. According to the characters of chemistry, mobility, and bioavailability of metals in urban street dust, we estimated the hazards on the environment and human health, which will help us to get more reasonable information for risk management of metals in urban environment.

  6. New land disposal restrictions on contaminated soil and debris, and newly identified toxicity characteristic organics

    International Nuclear Information System (INIS)

    Fortune, William B.; Schumann, Jean C.; Fallon, William E.; Badden, Janet W.; Smith, Edward H.


    The applicability of the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions (LDR) program to radioactive mixed wastes (RMW) has been clarified through U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE) rulemakings and notices. However, a number of waste management concerns involving RMW and RMW-contaminated soil and debris continue to exist with respect to achieving compliance with LDR provisions and treatment standards. Consequently, DOE has become increasingly proactive in its participation in the LDR rulemaking process and in the identification of LDR compliance issues associated with its RMW inventories. Both data and recommendations from across the DOE complex were collected and transmitted to EPA in response to proposed requirements that would implement LDR for contaminated soil and debris, and certain newly identified toxicity characteristic (TC) organics. Much of this information focused on concerns related to the application of proposed regulatory approaches to RMW streams. Highlights from the information included in these DOE responses are presented. (author)

  7. Study on the Implementation of Interaction Teaching Mode in Distance Education (United States)

    Zhou, Chunyu; Xu, Zhenhui


    By analyzing the learning characteristics of learners and the features of interactive teaching in distance education, this paper proposes the curriculum implementation subject of network education, namely objects multi-directional interaction teaching mode, so as to improve teaching effectiveness and achieve teaching objectives to ensure the…

  8. Interactive Methods for Teaching Action Potentials, an Example of Teaching Innovation from Neuroscience Postdoctoral Fellows in the Fellowships in Research and Science Teaching (FIRST) Program (United States)

    Keen-Rhinehart, E.; Eisen, A.; Eaton, D.; McCormack, K.


    Acquiring a faculty position in academia is extremely competitive and now typically requires more than just solid research skills and knowledge of one’s field. Recruiting institutions currently desire new faculty that can teach effectively, but few postdoctoral positions provide any training in teaching methods. Fellowships in Research and Science Teaching (FIRST) is a successful postdoctoral training program funded by the National Institutes of Health (NIH) providing training in both research and teaching methodology. The FIRST program provides fellows with outstanding interdisciplinary biomedical research training in fields such as neuroscience. The postdoctoral research experience is integrated with a teaching program which includes a How to Teach course, instruction in classroom technology and course development and mentored teaching. During their mentored teaching experiences, fellows are encouraged to explore innovative teaching methodologies and to perform science teaching research to improve classroom learning. FIRST fellows teaching neuroscience to undergraduates have observed that many of these students have difficulty with the topic of neuroscience. Therefore, we investigated the effects of interactive teaching methods for this topic. We tested two interactive teaching methodologies to determine if they would improve learning and retention of this information when compared with standard lectures. The interactive methods for teaching action potentials increased understanding and retention. Therefore, FIRST provides excellent teaching training, partly by enhancing the ability of fellows to integrate innovative teaching methods into their instruction. This training in turn provides fellows that matriculate from this program more of the characteristics that hiring institutions desire in their new faculty. PMID:23493377

  9. Acute toxicity of ingested fluoride. (United States)

    Whitford, Gary Milton


    This chapter discusses the characteristics and treatment of acute fluoride toxicity as well as the most common sources of overexposure, the doses that cause acute toxicity, and factors that can influence the clinical outcome. Cases of serious systemic toxicity and fatalities due to acute exposures are now rare, but overexposures causing toxic signs and symptoms are not. The clinical course of systemic toxicity from ingested fluoride begins with gastric signs and symptoms, and can develop with alarming rapidity. Treatment involves minimizing absorption by administering a solution containing calcium, monitoring and managing plasma calcium and potassium concentrations, acid-base status, and supporting vital functions. Approximately 30,000 calls to US poison control centers concerning acute exposures in children are made each year, most of which involve temporary gastrointestinal effects, but others require medical treatment. The most common sources of acute overexposures today are dental products - particularly dentifrices because of their relatively high fluoride concentrations, pleasant flavors, and their presence in non-secure locations in most homes. For example, ingestion of only 1.8 ounces of a standard fluoridated dentifrice (900-1,100 mg/kg) by a 10-kg child delivers enough fluoride to reach the 'probably toxic dose' (5 mg/kg body weight). Factors that may influence the clinical course of an overexposure include the chemical compound (e.g. NaF, MFP, etc.), the age and acid-base status of the individual, and the elapsed time between exposure and the initiation of treatment. While fluoride has well-established beneficial dental effects and cases of serious toxicity are now rare, the potential for toxicity requires that fluoride-containing materials be handled and stored with the respect they deserve. Copyright © 2011 S. Karger AG, Basel.

  10. Potential characteristics that relate to teachers mathematics-related beliefs (United States)

    Purnomo, Y. W.; Aziz, T. A.; Pramudiani, P.; Darwis, S.; Suryadi, D.


    A characteristic of the persons was very potential to affect the beliefs they held. This study examines whether there was a significant difference between the beliefs factors with characteristics such as gender, teaching experience, certification status, and grade level assignments. There were 325 primary school teachers in East Jakarta who participated in this research. MANOVA was applied to analyze the data. The findings of this study indicate that only on teaching experience, there was a significant difference between the beliefs held by the teachers, i.e. teachers who have 11-20 years teaching experience were more likely to think absolute than constructivism. Moreover, there was no difference between each belief they held with the other characteristics.

  11. A National Survey of Teaching Artists Working in Schools: Background, Preparation, Efficacy and School Experiences (United States)

    Snyder, Scott; Fisk, Timarie


    Several studies have described the characteristics and employment situations of teaching artists in the United States. This study adds to that literature by describing the characteristics of teaching artists working in K-12 school environments, the nature of the classroom roles of such teaching artists, the professional development and supervision…

  12. New ideas for teaching electrocardiogram interpretation and improving classroom teaching content

    Directory of Open Access Journals (Sweden)

    Zeng R


    Full Text Available Rui Zeng,1 Rong-Zheng Yue,2 Chun-Yu Tan,3 Qin Wang,4 Pu Kuang,5 Pan-Wen Tian,6 Chuan Zuo3 1Department of Cardiovascular Diseases, 2Department of Nephrology, 3Department of Rheumatology and Immunology, 4Department of Endocrinology, 5Department of Hematology, 6Department of Respiratory Diseases, West China Hospital, School of Clinic Medicine, Sichuan University, Chengdu, People’s Republic of China Background: Interpreting an electrocardiogram (ECG is not only one of the most important parts of diagnostics but also one of the most difficult areas to teach. Owing to the abstract nature of the basic theoretical knowledge of the ECG, its scattered characteristics, and tedious and difficult-to-remember subject matter, teaching how to interpret ECGs is as difficult for teachers to teach as it is for students to learn. In order to enable medical students to master basic knowledge of ECG interpretation skills in a limited teaching time, we modified the content used for traditional ECG teaching and now propose a new ECG teaching method called the “graphics-sequence memory method.” Methods: A prospective randomized controlled study was designed to measure the actual effectiveness of ECG learning by students. Two hundred students were randomly placed under a traditional teaching group and an innovative teaching group, with 100 participants in each group. The teachers in the traditional teaching group utilized the traditional teaching outline, whereas the teachers in the innovative teaching group received training in line with the proposed teaching method and syllabus. All the students took an examination in the final semester by analyzing 20 ECGs from real clinical cases and submitted their ECG reports. Results: The average ECG reading time was 32 minutes for the traditional teaching group and 18 minutes for the innovative teaching group. The average ECG accuracy results were 43% for the traditional teaching group and 77% for the innovative teaching

  13. The Situation and Countermeasures of Accounting Teaching in China


    Jinyu Yang


    The economic development proposes new issues for accounting teaching, which not only relies on educators¡¯ own perfection as well as the joint efforts of the accounting practitioners and social parties. The author briefly described the new circumstances the accounting education faces in recent years, summarized the characteristics of accounting teaching and proposed countermeasures to these accounting teaching issues.

  14. Optimization of Multimedia English Teaching in Context Creation (United States)

    Yang, Weiyan; Fang, Fan


    Using multimedia to create a context to teach English has its unique advantages. This paper explores the characteristics of multimedia and integrates how to use multimedia to optimize the context of English teaching as its purpose. In this paper, eight principles, specifically Systematization, Authenticity, Appropriateness, Interactivity,…

  15. Leaching Behavior of Heavy Metals from Cement Pastes Using a Modified Toxicity Characteristic Leaching Procedure (TCLP). (United States)

    Huang, Minrui; Feng, Huajun; Shen, Dongsheng; Li, Na; Chen, Yingqiang; Shentu, Jiali


    As the standard toxicity characteristic leaching procedure (TCLP) can not exhaust the acid neutralizing capacity of the cement rotary kiln co-processing solid wastes products which is particularly important for the assessment of the leaching concentrations of heavy metals. A modified TCLP was proposed. The extent of leaching of heavy metals is low using the TCLP and the leaching performance of the different metals can not be differentiated. Using the modified TCLP, however, Zn leaching was negligible during the first 180 h and then sharply increased (2.86 ± 0.18 to 3.54 ± 0.26 mg/L) as the acidity increased (pH leaching is enhanced using the modified TCLP. While Pb leached readily during the first 126 h and then leachate concentrations decreased to below the analytical detection limit. To conclude, this modified TCLP is a more suitable method for these cement rotary kiln co-processing products.

  16. Early Combination of Material Characteristics and Toxicology Is Useful in the Design of Low Toxicity Carbon Nanofiber

    Directory of Open Access Journals (Sweden)

    Tore Syversen


    Full Text Available This paper describes an approach for the early combination of material characterization and toxicology testing in order to design carbon nanofiber (CNF with low toxicity. The aim was to investigate how the adjustment of production parameters and purification procedures can result in a CNF product with low toxicity. Different CNF batches from a pilot plant were characterized with respect to physical properties (chemical composition, specific surface area, morphology, surface chemistry as well as toxicity by in vitro and in vivo tests. A description of a test battery for both material characterization and toxicity is given. The results illustrate how the adjustment of production parameters and purification, thermal treatment in particular, influence the material characterization as well as the outcome of the toxic tests. The combination of the tests early during product development is a useful and efficient approach when aiming at designing CNF with low toxicity. Early quality and safety characterization, preferably in an iterative process, is expected to be efficient and promising for this purpose. The toxicity tests applied are preliminary tests of low cost and rapid execution. For further studies, effects such as lung inflammation, fibrosis and respiratory cancer are recommended for the more in-depth studies of the mature CNF product.

  17. Toxicity assessment and selective leaching characteristics of Cu-Al-Ni shape memory alloys in biomaterials applications. (United States)

    Chang, Shih-Hang; Chen, Bor-Yann; Lin, Jin-Xiang


    Cu-Al-Ni shape memory alloys (SMAs) possess two-way shape memory effects, superelasticity, and damping capacity. Nonetheless, Cu-Al-Ni SMAs remain promising candidates for use in biomedical applications, as they are more economical and machinable than other SMAs. Ensuring the biocompatibility of Cu-Al-Ni SMAs is crucial to their development for biomedical applications. Therefore, this study aimed to assess the toxicity of Cu-Al-Ni SMAs using a Probit dose-response model and augmented simplex design. In this study, the effects of Cu2+, Al3+ and Ni2+ metal ions on bacteria (Escherichia coli DH5α) using Probit dose-response analysis and augmented simplex design to assess the actual toxicity of the Cu-Al-Ni SMAs. Extraction and repetition of Escherichia coli DH5α solutions with high Cu2+ ion concentrations and 30-hour incubation demonstrated that Escherichia coli DH5α was able to alter its growth mechanisms in response to toxins. Metal ions leached from Cu-Al-Ni SMAs appeared in a multitude of compositions with varying degrees of toxicity, and those appearing close to a saddle region identified in the contour plot of the augmented simplex model were identified as candidates for elevated toxicity levels. When the Cu-13.5Al-4Ni SMA plate was immersed in Ringer's solution, the selective leaching rate of Ni2+ ions far exceeded that of Cu2+ and Al3+. The number of Cu2+, Al3+ and Ni2+ ions leached from Cu-Al-Ni SMAs increased with immersion time; however, at higher ratios, toxicity interactions among the metal ions had the effect of gradually reducing overall toxicity levels with regard to Escherichia coli DH5α. The quantities of Cu2+, Al3+ and Ni2+ ions leached from the Cu-13.5Al-4Ni SMA plate increased with immersion time, the toxicity interactions associated with these compositions reduced the actual toxicity to Escherichia coli DH5α.

  18. The Flipped Classroom Teaching Model and Its Use for Information Literacy Instruction

    Directory of Open Access Journals (Sweden)

    Sara Arnold-Garza


    Full Text Available The “flipped classroom” teaching model has emerged in a variety of educational settings. It provides many advantages for students and exploits the affordances of modern technology. This article describes some of the pedagogical and logistical characteristics of the flipped teaching model. It situates the flipped classroom in higher education and library instruction, and make the case that there are characteristics of information literacy instruction that fit well with the flipped teaching model, in addition to providing some unique challenges.



    Muhammad Jarir


    This paper examined the most important methods used in the teaching of Islamic fiqh at the university level. The paper identified two types of methods and highlighted their advantages and disadvantages. The study particularly highlighted the Islamic perception of the methods and the optimal characteristics of a fiqh instructor. The paper concluded with a number of suggestion and recommendation that’s my correct the course of university teaching of Islamic fiqh. The paper mainly calls for the ...

  20. Developing Metrics for Effective Teaching in Agricultural Education (United States)

    Lawver, Rebecca G.; McKim, Billy R.; Smith, Amy R.; Aschenbrener, Mollie S.; Enns, Kellie


    Research on effective teaching has been conducted in a variety of settings for more than 40 years. This study offers direction for future effective teaching research in secondary agricultural education and has implications for career and technical education. Specifically, 142 items consisting of characteristics, behaviors, and/or techniques…

  1. Uses of Technology to Support Reflective Teaching Practices (United States)

    Brent, Wayne


    This dissertation researched and reported on how technology was used to facilitate and inform reflective teaching practices. It also identified the characteristics of benefits and barriers in using technology for teaching and reflection. The study, descriptive in nature, was designed to determine the reflective practices of instructors and how…

  2. Innovative Research on Teaching Model of Environmental Law Courses in China


    Yuling Li


    At present, the teaching model of environmental law courses in China is mainly lecture-based learning (LBL) teaching model whose disadvantages are closeness, unidirection and weak teaching practice. This model does not fit in with the characteristics of environmental law courses and the objective changes of ecological civilized society for the demand of talents of environmental law. Therefore, we should actively reform the current single teaching model, learn from foreign advanced teaching co...

  3. Perceptions of medical school graduates and students regarding their academic preparation to teach. (United States)

    Henry, B W; Haworth, J G; Hering, P


    How medical students learn and develop the characteristics associated with good teaching in medicine is not well known. Information about this process can improve the academic preparation of medical students for teaching responsibilities. The purpose of this study was to determine how different experiences contributed to the knowledge, skills, and attitudes of medical school graduates and students regarding medical teaching. A questionnaire was developed, addressing reliability and validity considerations, and given to first year residents and third year medical students (taught by those residents). Completed questionnaires were collected from 76 residents and 110 students (81% of the sample group). Item responses were analysed using descriptive and inferential statistics. Most residents (n = 54; 71%) positively viewed opportunities they had to practice teaching when they were seniors. Residents rated three activities for learning to teach highest: (1) observing teachers as they teach; (2) reviewing the material to be taught; and (3) directly teaching students; representing both individual and participatory ways of learning. Residents' self ratings of teaching behaviours improved over time and this self assessment by the residents was validated by the students' responses. Comparison between residents' self ratings and students' views of typical resident teaching behaviours showed agreement on levels of competence, confidence, and motivation. The students rated characteristics of enthusiasm, organisation, and fulfilment lower (pteaching responsibilities positively and showed agreement on characteristics of good teaching that may be helpful indicators in the process of developing medical teachers.

  4. Teaching methodology for the utilization of cinema in the teaching of medical microbiology and infectious diseases.

    Directory of Open Access Journals (Sweden)

    María José Fresnadillo Martínez


    Full Text Available Cinema, since it’s beginning, has been and is a social thermometer of the first magnitude reflecting the inequities of the population, among them are infectious diseases.  The caudal of images, sounds, and feelings that appear in the field support a very valid teaching resource, capable of complementing the classic teaching method and adapting the dynamic art of teaching to the actual educational tendencies.  If the definition of objectives and the teaching design are obligatory stages that should always be realized with rigor, in a method like this, because of its characteristics and youth, the control should be more exhaustive –before, during and after its execution- to avoid the “trivialization” to gain the maximum teaching efficiency that depends no as much on the material utilized (and its fundamental selection of films to accompany every unit taught like the use that is made of it.

  5. Characteristics of suspended solids affect bifenthrin toxicity to the calanoid copepods Eurytemora affinis and Pseudodiaptomus forbesi. (United States)

    Parry, Emily; Lesmeister, Sarah; Teh, Swee; Young, Thomas M


    Bifenthrin is a pyrethroid pesticide that is highly toxic to aquatic invertebrates. The dissolved concentration is generally thought to be the best predictor of acute toxicity. However, for the filter-feeding calanoid copepods Eurytemora affinis and Pseudodiaptomus forbesi, ingestion of pesticide-bound particles could prove to be another route of exposure. The present study investigated bifenthrin toxicity to E. affinis and P. forbesi in the presence of suspended solids from municipal wastewater effluent and surface water of the San Francisco (CA, USA) Estuary. Suspended solids mitigated the toxicity of total bifenthrin to E. affinis and P. forbesi, but mortality was higher than what would be predicted from dissolved concentrations alone. The results indicate that the toxicity and bioavailability of particle-associated bifenthrin was significantly correlated with counts of 0.5-µm to 2-µm particle sizes. Potential explanations could include direct ingestion of bifenthrin-bound particles, changes in food consumption and feeding behavior, and physical contact with small particles. The complex interactions between pesticides and particles of different types and sizes demonstrate a need for future ecotoxicological studies to investigate the role of particle sizes on aquatic organisms. © 2015 SETAC.

  6. Anthropomorphic Robot Hand And Teaching Glove (United States)

    Engler, Charles D., Jr.


    Robotic forearm-and-hand assembly manipulates objects by performing wrist and hand motions with nearly human grasping ability and dexterity. Imitates hand motions of human operator who controls robot in real time by programming via exoskeletal "teaching glove". Telemanipulator systems based on this robotic-hand concept useful where humanlike dexterity required. Underwater, high-radiation, vacuum, hot, cold, toxic, or inhospitable environments potential application sites. Particularly suited to assisting astronauts on space station in safely executing unexpected tasks requiring greater dexterity than standard gripper.

  7. Validation of a Teaching Effectiveness Assessment in Psychiatry Continuing Medical Education. (United States)

    Palmer, Brian A; Frye, Mark A; Vickers Douglas, Kristin S; Staab, Jeffrey P; Bright, Robert P; Schleck, Cathy D; Mandrekar, Jayawant N; Mahapatra, Saswati; Beckman, Thomas J; Wittich, Christopher M


    Little is known about factors associated with effective continuing medical education (CME) in psychiatry. The authors aimed to validate a method to assess psychiatry CME teaching effectiveness and to determine associations between teaching effectiveness scores and characteristics of presentations, presenters, and participants. This cross-sectional study was conducted at the Mayo Clinic Psychiatry Clinical Reviews and Psychiatry in Medical Settings. Presentations were evaluated using an eight-item CME teaching effectiveness instrument, its content based on previously published instruments. Factor analysis, internal consistency and interrater reliabilities, and temporal stability reliability were calculated. Associations were determined between teaching effectiveness scores and characteristics of presentations, presenters, and participants. In total, 364 participants returned 246 completed surveys (response rate, 67.6%). Factor analysis revealed a unidimensional model of psychiatry CME teaching effectiveness. Cronbach α for the instrument was excellent at 0.94. Item mean score (SD) ranged from 4.33 (0.92) to 4.71 (0.59) on a 5-point scale. Overall interrater reliability was 0.84 (95% CI, 0.75-0.91), and temporal stability was 0.89 (95% CI, 0.77-0.97). No associations were found between teaching effectiveness scores and characteristics of presentations, presenters, and participants. This study provides a new, validated measure of CME teaching effectiveness that could be used to improve psychiatry CME. In contrast to prior research in other medical specialties, CME teaching effectiveness scores were not associated with use of case-based or interactive presentations. This outcome suggests the need for distinctive considerations regarding psychiatry CME; a singular approach to CME teaching may not apply to all medical specialties.

  8. Selection of nursing teaching strategies in mainland China: A questionnaire survey. (United States)

    Zhou, HouXiu; Liu, MengJie; Zeng, Jing; Zhu, JingCi


    In nursing education, the traditional lecture and direct demonstration teaching method cannot cultivate the various skills that nursing students need. How to choose a more scientific and rational teaching method is a common concern for nursing educators worldwide. To investigate the basis for selecting teaching methods among nursing teachers in mainland China, the factors affecting the selection of different teaching methods, and the application of different teaching methods in theoretical and skill-based nursing courses. Questionnaire survey. Seventy one nursing colleges from 28 provincial-level administrative regions in mainland China. Following the principle of voluntary informed consent, 262 nursing teachers were randomly selected through a nursing education network platform and a conference platform. The questionnaire contents included the basis for and the factors influencing the selection of nursing teaching methods, the participants' common teaching methods, and the teaching experience of the surveyed nursing teachers. The questionnaires were distributed through the network or conference platform, and the data were analyzed by SPSS 17.0 software. The surveyed nursing teachers selected teaching methods mainly based on the characteristics of the teaching content, the characteristics of the students, and their previous teaching experiences. The factors affecting the selection of teaching methods mainly included large class sizes, limited class time, and limited examination formats. The surveyed nursing teachers primarily used lectures to teach theory courses and the direct demonstration method to teach skills courses, and the application frequencies of these two teaching methods were significantly higher than those of other teaching methods (P=0.000). More attention should be paid to the selection of nursing teaching methods. Every teacher should strategically choose teaching methods before each lesson, and nursing education training focused on selecting

  9. Identification of manganese as a toxicant in a groundwater treatment system: Addressing naturally occurring toxicants

    International Nuclear Information System (INIS)

    Goodfellow, W. Jr.; Sohn, V.; Richey, M.; Yost, J.


    Effluent from a groundwater remediation system at a bulk oil storage and distribution terminal has been chronically toxic to Ceriodaphnia dubia. The remediation system was designed in response to a hydrocarbon plume in the area of the terminal. The remediation system consists of a series of groundwater recovery wells and groundwater intercept trench systems with groundwater treatment and phased-separated hydrocarbon recovery systems. The groundwater treatment and petroleum recovery systems consist of oil/water separators, product recovery tanks, air strippers, filters, and carbon adsorption units. The characteristics of this effluent are low total suspended solids, total dissolved solids, and hardness concentrations as well as meeting stringent NPDES permit requirements for lead, copper, zinc, mercury, total petroleum hydrocarbons, and BTEX. Additional priority pollutant evaluations revealed no compounds of concern. Performance of a Toxicity identification Evaluation (TIE) indicated that manganese was the principle toxicant in the effluent. Manganese is a naturally occurring constituent in this groundwater source and is not added to the treatment system. This paper will present the results of the TIE with a discussion of treatability/control options for manganese control at this facility. Recommendations for addressing naturally occurring toxicants that are not a result of the facility's operations will also be presented

  10. Comparative metal oxide nanoparticle toxicity using embryonic zebrafish

    Directory of Open Access Journals (Sweden)

    Leah C. Wehmas


    Full Text Available Engineered metal oxide nanoparticles (MO NPs are finding increasing utility in the medical field as anticancer agents. Before validation of in vivo anticancer efficacy can occur, a better understanding of whole-animal toxicity is required. We compared the toxicity of seven widely used semiconductor MO NPs made from zinc oxide (ZnO, titanium dioxide, cerium dioxide and tin dioxide prepared in pure water and in synthetic seawater using a five-day embryonic zebrafish assay. We hypothesized that the toxicity of these engineered MO NPs would depend on physicochemical properties. Significant agglomeration of MO NPs in aqueous solutions is common making it challenging to associate NP characteristics such as size and charge with toxicity. However, data from our agglomerated MO NPs suggests that the elemental composition and dissolution potential are major drivers of toxicity. Only ZnO caused significant adverse effects of all MO particles tested, and only when prepared in pure water (point estimate median lethal concentration = 3.5–9.1 mg/L. This toxicity was life stage dependent. The 24 h toxicity increased greatly (∼22.7 fold when zebrafish exposures started at the larval life stage compared to the 24 h toxicity following embryonic exposure. Investigation into whether dissolution could account for ZnO toxicity revealed high levels of zinc ion (40–89% of total sample were generated. Exposure to zinc ion equivalents revealed dissolved Zn2+ may be a major contributor to ZnO toxicity.

  11. The Integration of technology in teaching mathematics (United States)

    Muhtadi, D.; Wahyudin; Kartasasmita, B. G.; Prahmana, R. C. I.


    This paper presents the Transformation of Technological Pedagogical and Content Knowledge (TPACK) of three pre-service math teacher. They participate in technology-based learning modules aligned with teaching practice taught school and became characteristic of teaching method by using the mathematical software. ICT-based learning environment has been the demands in practice learning to build a more effective approach to the learning process of students. Also, this paper presents the results of research on learning mathematics in middle school that shows the influence of design teaching on knowledge of math content specifically.

  12. The teaching/research trade-off in law: data from the right tail. (United States)

    Ginsburg, Tom; Miles, Thomas J


    There is a long scholarly debate on the trade-off between research and teaching in various fields, but relatively little study of the phenomenon in law. This analysis examines the relationship between the two core academic activities at one particular school, the University of Chicago Law School, which is considered one of the most productive in legal academia. We measure of scholarly productivity with the total number of publications by each professor for each year, and we approximate performance in teaching with course loads and average scores in student evaluations for each course. In OLS regressions, we estimate scholarly output as a function of teaching loads, faculty characteristics, and other controls. We also estimate teaching evaluation scores as a function of scholarly productivity, fixed effects for years and course subject, and faculty characteristics. Net of other factors, we find that, under some specifications, research and teaching are positively correlated. In particular, we find that students' perceptions of teaching quality rises, but at a decreasing rate, with the total amount of scholarship. We also find that certain personal characteristics correlate with productivity. The recent debate on the mission of American law schools has hinged on the assumption that a trade-off exists between teaching and research, and this article's analysis, although limited in various ways, casts some doubt on that assumption. © The Author(s) 2014.

  13. Comparison of three-stage sequential extraction and toxicity characteristic leaching tests to evaluate metal mobility in mining wastes

    International Nuclear Information System (INIS)

    Margui, E.; Salvado, V.; Queralt, I.; Hidalgo, M.


    Abandoned mining sites contain residues from ore processing operations that are characterised by high concentrations of heavy metals. The form in which a metal exists strongly influences its mobility and, thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. In this work, the modified three-stage sequential extraction procedure proposed by the BCR (now the Standards, Measurements and Testing Programme) was applied for the fractionation of Ni, Zn, Pb and Cd in mining wastes from old Pb-Zn mining areas located in the Val d'Aran (NE Spain) and Cartagena (SE Spain). Analyses of the extracts were performed by inductively coupled plasma atomic emission spectrometry and electrothermal atomic absorption spectrometry. The procedure was evaluated by using a certified reference material, BCR-701. The results of the partitioning study indicate that more easily mobilised forms (acid exchangeable) were predominant for Cd and Zn, particularly in the sample from Cartagena. In contrast, the largest amount of lead was associated with the iron and manganese oxide fractions. On the other hand, the applicability of lixiviation tests commonly used to evaluate the leaching of toxic species from landfill disposal (US-EPA Toxicity Characteristic Leaching Procedure and DIN 38414-S4) to mining wastes was also investigated and the obtained results compared with the information on metal mobility derivable from the application of the three-stage sequential extraction procedure

  14. The Universality of Good Teaching: A Study of Descriptors across Disciplines (United States)

    Samples, Jerry W.; Copeland, Susan E.


    The literature on teaching is replete with definitions and examples of good teaching. They include the traits and characteristics of the best instructors, teachers, and professors. In recent years, the literature included the impact of teaching on the student learner, thus coming full circle, from teacher to learner. The literature provides good…

  15. A comparative assessment of the acute inhalation toxicity of vanadium compounds. (United States)

    Rajendran, N; Seagrave, J C; Plunkett, L M; MacGregor, J A


    Vanadium compounds have become important in industrial processes, resulting in workplace exposure potential and are present in ambient air as a result of fossil fuel combustion. A series of acute nose-only inhalation toxicity studies was conducted in both rats and mice in order to obtain comparative data on the acute toxicity potential of compounds used commercially. V 2 O 3 , V 2 O 4 , and V 2 O 5 , which have different oxidation states (+3, +4, +5, respectively), were delivered as micronized powders; the highly water-soluble and hygroscopic VOSO 4 (+4) could not be micronized and was instead delivered as a liquid aerosol from an aqueous solution. V 2 O 5 was the most acutely toxic micronized powder in both species. Despite its lower overall percentage vanadium content, a liquid aerosol of VOSO 4 was more toxic than the V 2 O 5 particles in mice, but not in rats. These data suggest that an interaction of characteristics, i.e., bioavailability, solubility and oxidation state, as well as species sensitivity, likely affect the toxicity potential of vanadium compounds. Based on clinical observations and gross necropsy findings, the lung appeared to be the target organ for all compounds. The level of hazard posed will depend on the specific chemical form of the vanadium. Future work to define the inhalation toxicity potential of vanadium compounds of various oxidation states after repeated exposures will be important in understanding how the physico-chemical and biological characteristics of specific vanadium compounds interact to affect toxicity potential and the potential risks posed to human health.

  16. teacher characteristics and students' choice of teaching as a career

    African Journals Online (AJOL)

    Engr E. Egbochukwu

    choice of teaching as a career among secondary school students in Osun state, Nigeria. ... as a career. The study also showed a significant relationship between ... follows that how the students perceive their environment, personality, and opportunity will also ..... status and their children's, occupational preference. Journal of.

  17. Teaching Introductory Statistics to Blind Students (United States)

    Marson, Stephen M.; Harrington, Charles F.; Walls, Adam


    The challenges of learning statistics, particularly distributions and their characteristics, can be potentially monumental for vision impaired and blind students. The authors provide some practical advice for teaching these students.

  18. A Science Education that Promotes the Characteristics of Science and Scientists: Features of teaching

    Directory of Open Access Journals (Sweden)

    Michael P. Clough


    Full Text Available Effectively teaching about science, technology, engineering and mathematics (STEM is far more complex than policymakers, the public, and even many teachers realize. Leinhardt and Greeno (1986, p. 75 write that “teaching occurs in a relatively ill-structured, dynamic environment”, and this is even more so the case when attempting to teach STEM through inquiry (activities that require significant student decision-making and sense-making, and the necessary pedagogical practices that support student learning in those experiences and as inquiry (helping students understand how knowledge in STEM disciplines is developed and comes to be accepted.

  19. The Teacher and the Teaching Profession - An Ecological Adaptation. (United States)

    Zak, Itai

    This study aimed at assessing the relationships between the structures of the teaching occupation and teacher training institutions and the personality characteristics of teachers in Israel. The hypothesis considered was that recruitment by self-selection would promote an image of conservatism by bringing into teaching people with matched…

  20. TRIGA reactor characteristics

    International Nuclear Information System (INIS)

    Boeck, H.; Villa, M.


    This module describes the general design, characteristics and parameters of TRIGA reactors and fuels. It is recommended that most of this information should be incorporated into any reactor operator training program and, in many cases, the facility Safety Analysis Report. It is oriented to teach the basics of the physics and mechanical design of the TRIGA fuel as well as its unique operational characteristics and the differences between TRIGA fuels and others more traditional reactor fuels. (nevyjel)

  1. Dosimetric characteristics of PASSAG as a new polymer gel dosimeter with negligible toxicity (United States)

    Farhood, Bagher; Abtahi, Seyed Mohammad Mahdi; Geraily, Ghazale; Ghorbani, Mehdi; Mahdavi, Seied Rabi; Zahmatkesh, Mohammad Hasan


    Despite many advantages of polymer gel dosimeters, their clinical use is only not realized now. Toxicity of polymer gel dosimeters can be considered as one of their main limitations for use in routine clinical applications. In the current study, a new polymer gel dosimeter is introduced with negligible toxicity. For this purpose, 2-Acrylamido-2-Methy-1-PropaneSulfonic acid (AMPS) sodium salt monomer was replaced instead of acrylamide monomer used in PAGAT gel dosimeter by using %6 T and %50 C to the gel formula and the new formulation is called PASSAG (Poly AMPS Sodium Salt and Gelatin) polymer gel dosimeter. The irradiation of gel dosimeters was carried out using a Co-60 therapy machine. MRI technique was used to quantify the dose responses of the PASSAG gel dosimeter. Then, the MRI responses (R2) of the gel dosimeter was analyzed at different dose values, post-irradiation times, and scanning temperatures. The results showed that the new gel formulation has a negligible toxicity and it is also eco-friendly. In addition, carcinogenicity and genetic toxicity tests are negative for the monomer used in PASSAG. The radiological properties of PASSAG gel dosimeter showed that this substance can be considered as a soft tissue/water equivalent material. Furthermore, dosimetric evaluation of the new polymer gel dosimeter revealed an excellent linear R2-dose response in the evaluated dose range (0-15 Gy). The R2-dose sensitivity and dose resolution of PASSAG gel dosimeter were 0.081 s-1Gy-1 (in 0-15 Gy dose range) and 1 Gy (in 0-10 Gy dose range), respectively. Moreover, it was shown that the R2-dose sensitivity and dose resolution of the new gel dosimeter improves over time after irradiation. It was also found that the R2 response of the PASSAG gel dosimeter has less dependency to the 18, 20, and 24 °C scanning temperature in comparison to that of room temperature (22 °C).

  2. Applying Bandura's Model to Identifying Sources of Self-Efficacy of Teaching Artists (United States)

    Snyder, Scott; Fisk, Timarie


    Teaching artists have significant roles within K-12 schools. Although some research has been conducted to describe the characteristics, training, and employment experiences of teaching artists, no study has been conducted concerning the self-efficacy that such individuals have regarding teaching. The purpose of the study was to investigate the…

  3. Rewarding quality teaching in higher education: the evading dream ...

    African Journals Online (AJOL)

    Teaching, and specifically quality teaching, has for many centuries been the defining characteristic of the academic profession. However, since the dawning of the 20th century, it seems that the very basis of the global higher education institutional reward system is the belief that working with, contributing to, and pursuing ...

  4. Cerebral CT appearances of toxic encephalopathy of tetramine

    International Nuclear Information System (INIS)

    Zheng Wenlong; Wu Aiqin; Xu Chongyong; Ying Binyu; Hong Ruizhen


    Objective: To investigate the cerebral CT appearances of toxic encephalopathy of tetramine and improve the recognition on this disease. Methods: Four cases of toxic encephalopathy of tetramine were collected and their cerebral CT appearances were retrospectively analyzed. Results: Cerebral CT appearances in acute phase (within 8 days): (1) cerebral edema in different degree. CT abnormalities consisted of cortical hypodensities and complete loss of gray-white matter differentiation. The CT value were in 11-13 HU, and to be watery density in serious case, (2) subarachnoid hemorrhage. It demonstrated the signs of poisoning hypoxic ischemic encephalopathy in chronic phase. Conclusion: The cerebral CT appearances of toxic encephalopathy of tetramine had some character in acute phase and it can predict the serious degree of intoxication, but there was no characteristic findings in chronic phase

  5. Bryophytes as Teaching Materials on the Textbook of Botany (The Latter Term of Meiji to the Beginning of Showa) and Suggestions for Development of New Teaching Material


    Sato, Takayuki; Muko, Heiwa; Ohshika, Kiyoyuki


    Bryophytes have some characteristics as teaching material, but it is very difficult to use them in secondary education. Nevertheless, from the latter term of Meiji to the beginning of Showa, there are many teaching materials for natural history.Therefore, we analyzed teaching materials on the textbook of botany that was published at the period, take suggestions for newly development of teaching material. We analyzed composition of textbooks and species of Bryophytes, and compared them to a ma...

  6. Statistics Graduate Students' Professional Development for Teaching: A Communities of Practice Model (United States)

    Justice, Nicola

    Graduate teaching assistants (GTAs) are responsible for instructing approximately 25% of introductory statistics courses in the United States (Blair, Kirkman, & Maxwell, 2013). Most research on GTA professional development focuses on structured activities (e.g., courses, workshops) that have been developed to improve GTAs' pedagogy and content knowledge. Few studies take into account the social contexts of GTAs' professional development. However, GTAs perceive their social interactions with other GTAs to be a vital part of their preparation and support for teaching (e.g., Staton & Darling, 1989). Communities of practice (CoPs) are one way to bring together the study of the social contexts and structured activities of GTA professional development. CoPs are defined as groups of practitioners who deepen their knowledge and expertise by interacting with each other on an ongoing basis (e.g., Lave & Wenger, 1991). Graduate students may participate in CoPs related to teaching in many ways, including attending courses or workshops, participating in weekly meetings, engaging in informal discussions about teaching, or participating in e-mail conversations related to teaching tasks. This study explored the relationship between statistics graduate students' experiences in CoPs and the extent to which they hold student-centered teaching beliefs. A framework for characterizing GTAs' experiences in CoPs was described and a theoretical model relating these characteristics to GTAs' beliefs was developed. To gather data to test the model, the Graduate Students' Experiences Teaching Statistics (GETS) Inventory was created. Items were written to collect information about GTAs' current teaching beliefs, teaching beliefs before entering their degree programs, characteristics of GTAs' experiences in CoPs, and demographic information. Using an online program, the GETS Inventory was administered to N =218 statistics graduate students representing 37 institutions in 24 different U.S. states

  7. Characteristics of smokers and their knowledge about smoking at a teaching hospital in Karachi

    International Nuclear Information System (INIS)

    Qidwai, W.; Zahid, N.


    Objective: To study the characteristics of smokers and their knowledge about smoking, among Family Practice Patients, at a teaching hospital in Karachi, Pakistan. Main outcome measures: Age at starting smoking, duration and number of cigarettes smoked, started smoking under influence of friends, colleagues, family members or self motivation, number of friends and colleagues who smoked, whether smoking is unhealthy, and actual chance of harm to an individual due to smoking is very rare or not. Results: One hundred patients who visited Family Practice Center were interviewed. Sixty one percent were young married men, well educated and either student, in private service, self employed or unemployed. Eighty-four (84%) smokers started smoking between 16-25 years of age, and smoked 6-20 cigarettes daily for two to twenty five years. Sixty-nine (69%) of them started smoking under the influence of friends and had 3-5 friends and colleagues who smoked. 91% of smokers believed that smoking is unhealthy and were aware that it causes lung cancer and heart disease. Majority of them (69%) believed that the actual harm of smoking to an individual is not very rare. Conclusion: We have documented the characteristics of smokers and their knowledge about smoking among Family Practice patients. Majority of the respondents started smoking at a young age under the influence of friends though they were aware of its harmful effects. Though the sample size is small but it does give an indication about the responsible factors to plan interventional preventive strategies. (author)

  8. Using aquatic macroinvertebrate species traits to build test batteries for sediment toxicity assessment: accounting for the diversity of potential biological responses to toxicants. (United States)

    Ducrot, Virginie; Usseglio-Polatera, Philippe; Péry, T Alexandre R R; Mouthon, Jacques; Lafont, Michel; Roger, Marie-Claude; Garric, Jeanne; Férard, Jean-François


    An original species-selection method for the building of test batteries is presented. This method is based on the statistical analysis of the biological and ecological trait patterns of species. It has been applied to build a macroinvertebrate test battery for the assessment of sediment toxicity, which efficiently describes the diversity of benthic macroinvertebrate biological responses to toxicants in a large European lowland river. First, 109 potential representatives of benthic communities of European lowland rivers were selected from a list of 479 taxa, considering 11 biological traits accounting for the main routes of exposure to a sediment-bound toxicant and eight ecological traits providing an adequate description of habitat characteristics used by the taxa. Second, their biological and ecological trait patterns were compared using coinertia analysis. This comparison allowed the clustering of taxa into groups of organisms that exhibited similar life-history characteristics, physiological and behavioral features, and similar habitat use. Groups exhibited various sizes (7-35 taxa), taxonomic compositions, and biological and ecological features. Main differences among group characteristics concerned morphology, substrate preferendum and habitat utilization, nutritional features, maximal size, and life-history strategy. Third, the best representatives of the mean biological and ecological characteristics of each group were included in the test battery. The final selection was composed of Chironomus riparius (Insecta: Diptera), Branchiura sowerbyi (Oligochaeta: Tubificidae), Lumbriculus variegatus (Oligochaeta: Lumbriculidae), Valvata piscinalis (Gastropoda: Valvatidae), and Sericostoma personatum (Trichoptera: Sericostomatidae). This approach permitted the biological and ecological variety of the battery to be maximized. Because biological and ecological traits of taxa determine species sensitivity, such maximization should permit the battery to better account

  9. Thyroid cancer in toxic and non-toxic multinodular goiter

    Directory of Open Access Journals (Sweden)

    Cerci C


    Full Text Available Background : Many authors have claimed that hyperthyroidism protects against thyroid cancer and believed that the incidence of malignancy is lower in patients with toxic multinodular goiter (TMG than in those with non-toxic multinodular goiter. But in recent studies, it was reported that the incidence of malignancy with TMG is not as low as previously thought. Aim : To compare the thyroid cancer incidence in patients with toxic and non-toxic multinodular goiter. Settings and Design : Histology reports of patients treated surgically with a preoperative diagnosis of toxic and non-toxic multinodular goiter were reviewed to identify the thyroid cancer incidence. Patients having a history of neck irradiation or radioactive iodine therapy were excluded from the study. Materials and Methods : We reviewed 294 patients operated between 2001-2005 from toxic and non-toxic multinodular goiter. One hundred and twenty-four of them were toxic and 170 were non-toxic. Hyperthyroidism was diagnosed by elevated tri-iodothyroinine / thyroxine ratios and low thyroid-stimulating hormone with clinical signs and symptoms. All patients were evaluated with ultrasonography and scintigraphy and fine needle aspiration biopsy. Statistical Analysis Used : Significance of the various parameters was calculated by using ANOVA test. Results : The incidence of malignancy was 9% in the toxic and 10.58% in the non-toxic multinodular goiter group. Any significant difference in the incidence of cancer and tumor size between the two groups could not be detected. Conclusions : The incidence of malignancy in toxic multinodular goiter is not very low as thought earlier and is nearly the same in non-toxic multinodular goiter.

  10. Toxicity evaluation of the process effluent streams of a petrochemical industry. (United States)

    Reis, J L R; Dezotti, M; Sant'Anna, G L


    The physico-chemical characteristics and the acute toxicity of several wastewater streams, generated in the industrial production of synthetic rubber, were determined. The acute toxicity was evaluated in bioassays using different organisms: Danio rerio (fish), Lactuca sativa (lettuce) and Brachionus calyciflorus (rotifer). The removal of toxicity attained in the industrial wastewater treatment plant was also determined upstream and downstream of the activated sludge process. The results obtained indicate that the critical streams in terms of acute toxicity are the effluents from the liquid polymer unit and the spent caustic butadiene washing stage. The biological treatment was able to partially remove the toxicity of the industrial wastewater. However, a residual toxicity level persisted in the biotreated wastewater. The results obtained with Lactuca sativa showed a high degree of reproducibility, using root length or germination index as evaluation parameters. The effect of volatile pollutants on the toxicity results obtained with lettuce seeds was assessed, using ethanol as a model compound. Modifications on the assay procedure were proposed. A strong correlation between the toxic responses of Lactuca sativa and Danio rerio was observed for most industrial effluent streams.

  11. Management of low and intermediate level radioactive wastes with regard to their chemical toxicity

    International Nuclear Information System (INIS)


    A preliminary overview is provided of management options for low and intermediate level radioactive waste (LILW) with regard to its chemical toxicity. In particular, the following issues are identified and described associated with the management and safe disposal of chemically toxic materials in LILW: the origin and characteristics; the regulatory approaches; the pre-disposal management; the disposal; the safety assessment. Also included are: regulatory framework for chemically toxic low level wastes in the USA; pre-disposal processing options for LILW containing chemically toxic components; example treatment technologies for LILW containing chemically toxic components and safety assessment case studies for Germany, Belgium, France and Sweden

  12. Exploring Environmental Inequity in South Korea: An Analysis of the Distribution of Toxic Release Inventory (TRI Facilities and Toxic Releases

    Directory of Open Access Journals (Sweden)

    D. K. Yoon


    Full Text Available Recently, location data regarding the Toxic Release Inventory (TRI in South Korea was released to the public. This study investigated the spatial patterns of TRIs and releases of toxic substances in all 230 local governments in South Korea to determine whether spatial clusters relevant to the siting of noxious facilities occur. In addition, we employed spatial regression modeling to determine whether the number of TRI facilities and the volume of toxic releases in a given community were correlated with the community’s socioeconomic, racial, political, and land use characteristics. We found that the TRI facilities and their toxic releases were disproportionately distributed with clustered spatial patterning. Spatial regression modeling indicated that jurisdictions with smaller percentages of minorities, stronger political activity, less industrial land use, and more commercial land use had smaller numbers of toxic releases, as well as smaller numbers of TRI facilities. However, the economic status of the community did not affect the siting of hazardous facilities. These results indicate that the siting of TRI facilities in Korea is more affected by sociopolitical factors than by economic status. Racial issues are thus crucial for consideration in environmental justice as the population of Korea becomes more racially and ethnically diverse.

  13. Functional Genomics of a Non-Toxic Alexandrium Lusitanicum Culture

    National Research Council Canada - National Science Library

    Martins, Claudia A


    .... The loss of toxicity was accompanied by a reduction in growth capability. A subculture of this isolate maintains the ability to produce toxins and to grow at rates and to cell abundances that were characteristic of the original Alexandrium culture...


    Directory of Open Access Journals (Sweden)

    M Burhan R Wijaya


    Full Text Available This study aims to identify and develop management models Factory Teaching Vocational School through a series of tests and validation of the model with the approach of reasearch and Development. Teaching Factory Management Models at Vocational Schools is a concept that combines learning management approach learning Competency Based Training (CBT and Production Based Training (PBT in the real atmosphere so that the process of achieving competence or skill skills life skills (life skills in accordance with the standards of graduate work in the industrial world. In particular, this study aims to formulate design management model development Teaching Factory Vocational School. To achieve the research objectives above using the approach of Research and Development, through preliminary studies, design development models, testing and validation. Preliminary study phase is planned to take the flow / stage as follows: the study of literature, study / collection of field data, and a description and analysis of field findings (factual, namely: (1 the description of the characteristics of vocational school with a standard performance indicators that can be poured as the content of the development of Teaching Factory, (2 description of the characteristics and potential development group management model Tefa as an outcome groups to develop and implement management models Tefa for Vocational Schools (3 description of the characteristics of potential stakeholders to support the development and implementation TEFA management model, and (4 preparation of the management model TEFA for Vocational Schools excellence and innovative. Trial design done on a limited scale model group. Then the model was accompanied by outcome group to develop and implement a model TEFA for Vocational Schools to determine whether the model developed can be applied correctly. Data analysis in this study, the preliminary study stage, the findings or the facts about productive learning

  15. Gender in the Teaching Profession: University Students’ Views of Teaching as a Career

    Directory of Open Access Journals (Sweden)

    Veronika Tašner


    Full Text Available The purpose of our research is to gain a better insight into what encourages young adults, in particular young women, to enter the teaching profession. The empirical part of the article is based on a pilot study including 132 students, with data collection being based on a survey approach using a questionnaire. The research attempts to address the context from which the desired characteristics of pre-service teachers with regard to their future employment arise. We have therefore tried to single out factors influencing the choice of teaching as a career, and to examine pre-service teachers’ attitudes towards the reputation of female and male teachers. The data obtained confirm the thesis that the predominance of women in the teaching profession(s is an effect of the harmonisation of the female respondents’ habitus and their perception of the field they are entering. The perception of the teaching profession as a vocation (calling that can be linked to the concepts of caring, giving and helping also proves to be very important. The data also confirms the thesis that the orientation towards life and work balance is important to our respondents of both genders.

  16. Effects of soil organic matter content on cadmium toxicity in Eisenia fetida: implications for the use of biomarkers and standard toxicity tests. (United States)

    Irizar, A; Rodríguez, M P; Izquierdo, A; Cancio, I; Marigómez, I; Soto, M


    Bioavailability is affected by soil physicochemical characteristics such as pH and organic matter (OM) content. In addition, OM constitutes the energy source of Eisenia fetida, a well established model species for soil toxicity assessment. The present work aimed at assessing the effects of changes in OM content on the toxicity of Cd in E. fetida through the measurement of neutral red uptake (NRU) and mortality, growth, and reproduction (Organisation for Economic Co-operation and Development [OECD] Nos. 207 and 222). Complementarily, metallothionein (MT) and catalase transcription levels were measured. To decrease variability inherent to natural soils, artificial soils (Organization for Economic Cooperation and Development 1984) with different OM content (6, 10, and 14%) and spiked with Cd solutions at increasing concentrations were used. Low OM in soil decreased soil ingestion and Cd bioaccumulation but also increased Cd toxicity causing lower NRU of coelomocytes, 100 % mortality, and stronger reproduction impairment, probably due to the lack of energy to maintain protection mechanisms (production of MT).Cd bioaccumulation did not reflect toxicity, and OM played a pivotal role in Cd toxicity. Thus, OM content should be taken into account when using E. fetida in in vivo exposures for soil health assessment.

  17. The importance of understanding during the teaching process

    Directory of Open Access Journals (Sweden)

    Dubljanin Saša


    Full Text Available Learning in the teaching process often goes on without proper understanding which is one of important problems that modern didactics tries to solve. In order to direct the totality of teaching towards understanding it is necessary to answer the question what understanding is, which is why we analysed different philosophical views on the concept of understanding and stressed their semblance to pedagogic explanations. Different kinds of understanding were analyzed as well as their role and contribution in different teaching situations, especially in the context of problem solving. As an alternative to the teaching based on accumulation of knowledge the characteristics and some principles of teaching focused on understanding are described, and the need for stimulating and developing understanding as an important goal of education. The results of our research unequivocally show that learning with understanding enables students to memorize the teaching material better, as well as to understand the whole teaching subject and efficiently apply the acquired knowledge out of school, and leads to more flexible behaviour and better coping in everyday life.

  18. [Evaluation of flipped classroom teaching model in undergraduates education of oral and maxillofacial surgery]. (United States)

    Cai, Ming; Cao, Xia; Fang, Xiao; Wang, Xu-dong; Zhang, Li-li; Zheng, Jia-wei; Shen, Guo-fang


    Flipped classroom is a new teaching model which is different from the traditional teaching method. The history and characteristics of flipped classroom teaching model were introduced in this paper. A discussion on how to establish flipped classroom teaching protocol in oral and maxillofacial surgery education was carried out. Curriculum transformation, construction of education model and possible challenges were analyzed and discussed.

  19. An internet-based teaching file on clinical nuclear medicine

    International Nuclear Information System (INIS)

    Jiang Zhong; Wu Jinchang


    Objective: The goal of this project was to develop an internet-based interactive digital teaching file on nuclide imaging in clinical nuclear medicine, with the capability of access to internet. Methods: On the basis of academic teaching contents in nuclear medicine textbook for undergraduates who major in nuclear medicine, Frontpage 2000, HTML language, and JavaScript language in some parts of the contents, were utilized in the internet-based teaching file developed in this study. Results: A practical and comprehensive teaching file was accomplished and may get access with acceptable speed to internet. Besides basic teaching contents of nuclide imagings, a large number of typical and rare clinical cases, questionnaire with answers and update data in the field of nuclear medicine were included in the file. Conclusion: This teaching file meets its goal of providing an easy-to-use and internet-based digital teaching file, characteristically with the contents instant and enriched, and with the modes diversified and colorful

  20. Measuring Nurse Educators' Willingness to Adopt Inclusive Teaching Strategies. (United States)

    Levey, Janet A

    The purpose of the study was to examine the characteristics and relationships of nurse educators' teaching practices, knowledge, support, and willingness to adopt inclusive teaching strategies (WillAdITS). Adopting more inclusive teaching strategies based on universal design for instruction is an innovative way for educators to reach today's diverse student body. However, the pedagogy has not diffused into nursing education. Descriptive statistics and hierarchical multiple regression were used for analyzing data from 311 nurse educators in prelicensure and RN to BSN programs. The model explained 44.8 percent of the variance in WillAdITS. The best indicators for this pedagogy were knowledge of universal design for instruction, social system support for inclusive teaching strategies, multiple instructional formats, and years of teaching. Knowing factors influencing the adoption of inclusive teaching strategies can inform schools of nursing of areas needing further development in the preparation of novice to experienced educators to teach diverse learners.

  1. Can "Any" Teacher Teach Sexuality and HIV/AIDS? Perspectives of South African Life Orientation Teachers (United States)

    Helleve, Arnfinn; Flisher, Alan J.; Onya, Hans; Mukoma, Wanjiru; Klepp, Knut-Inge


    In this paper we explore the perceived desirable characteristics of South African Life Orientation teachers for teaching sexuality and HIV/AIDS. We also investigate the extent to which these characteristics can be understood as parts of a role script for teaching HIV/AIDS and sexuality. Data were collected from teachers who taught Grade Eight and…

  2. Developing the Teaching Profession: Factors Influencing Teachers’ Performance

    Directory of Open Access Journals (Sweden)

    Hamdi Serin


    Full Text Available Teachers always seek for possible ways to develop their teaching. There are many ways teachers can develop professionally. They can do this by generating new ideas or thinking deeply about reformulating what they do in class. Nevertheless, they cannot fully improve professional development on their own. Teachers can learn with the help of other people who have knowledge and experience in teaching and learning. They learn from in-service training programs that teach new techniques and approaches. Teacher development is a long-term process that requires systematic planning. Professional advancement in the teaching profession is based on some factors. This paper defines the characteristics of teachers’ professional development and aims to explain the factors it hinges upon.

  3. Toxic Anterior Segment Syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Özlem Öner


    Full Text Available Toxic anterior segment syndrome (TASS is a sterile intraocular inflammation caused by noninfectious substances, resulting in extensive toxic damage to the intraocular tissues. Possible etiologic factors of TASS include surgical trauma, bacterial endotoxin, intraocular solutions with inappropriate pH and osmolality, preservatives, denatured ophthalmic viscosurgical devices (OVD, inadequate sterilization, cleaning and rinsing of surgical devices, intraocular lenses, polishing and sterilizing compounds which are related to intraocular lenses. The characteristic signs and symptoms such as blurred vision, corneal edema, hypopyon and nonreactive pupil usually occur 24 hours after the cataract surgery. The differential diagnosis of TASS from infectious endophthalmitis is important. The main treatment for TASS formation is prevention. TASS is a cataract surgery complication that is more commonly seen nowadays. In this article, the possible underlying causes as well as treatment and prevention methods of TASS are summarized. (Turk J Oph thal mol 2011; 41: 407-13

  4. Anesthesiology residents' perspective about good teaching--a qualitative needs assessment. (United States)

    Ortwein, Heiderose; Blaum, Wolf E; Spies, Claudia D


    Germany, like many other countries, will soon have a shortage of qualified doctors. One reason for the dissatisfaction amongst medical residents are the relatively unstructured residency training programs despite increasing importance of outcome-based education. The aim of our study was to identify characteristics and requirements for good teaching during anesthesiology residency training from the resident's point of view. A consensus workshop with residents from all medical universities in Germany was held. Participants were allocated to one of the three topics, chosen based on a 2009 nationwide evaluation of residency. The three topics were (A) characteristics of helpful/good teachers, (B) characteristics of helpful/good conditions and (C) characteristics of helpful/good curricular structure. Each group followed a nominal group technique consensus process to define and rank characteristics for a good residency. 31 (79.5%) resident representatives were present. The consented results put emphasis on the importance of structured curricula including transparent goals and objectives, in training formative assessments and quality assurance measures for the program. Residents further long for trained trainers with formal teaching qualifications and protected teaching time. Good residency training requires careful consideration of all stakeholders' needs. Results reflect and extend previous findings and are at least to some degree easily implemented. These findings are an important step to establish a broader consensus within the discipline.

  5. Mr. Sherlock Holmes: Teaching Exemplar Extraordinary. (United States)

    Abrell, Ron


    Literature offers an unusually rich store of fictional characters from which all educators can learn much. Sherlock Holmes constitutes a model whose personal characteristics, love of truth, concern for his fellow man, and teaching ability exemplify the best in pedagogy. (Author)

  6. Slag-based materials for toxic metal and radioactive waste stabilization

    International Nuclear Information System (INIS)

    Langton, C.A.


    This paper discusses a salt solution that is a hazardous waste and has both corrosive and metal toxicity characteristics. Objectives of a wasteform designed to stabilize this solution are presented. Disposal site characterization studies are examined

  7. Teaching Strategies for Specialized Ensembles. (United States)

    Teaching Music, 1999


    Provides a strategy, from the book "Strategies for Teaching Specialized Ensembles," that addresses Standard 9A of the National Standards for Music Education. Explains that students will identify and describe the musical and historical characteristics of the classical era in music they perform and in audio examples. (CMK)

  8. Understanding resident ratings of teaching in the workplace: a multi-centre study

    NARCIS (Netherlands)

    Fluit, C.R.M.G.; Feskens, R.; Bolhuis, S.; Grol, R.; Wensing, M.; Laan, R.


    Providing clinical teachers with feedback about their teaching skills is a powerful tool to improve teaching. Evaluations are mostly based on questionnaires completed by residents. We investigated to what extent characteristics of residents, clinical teachers, and the clinical environment influenced


    Directory of Open Access Journals (Sweden)

    Svetlana V. Skvortsova


    Full Text Available The aim of the investigation is to find out the fundamentals of creative activity of pupils in a comprehensive school and reveal its main characteristics on the basis of analysis of the British system of education experience considering the original modern official educational documents devoted to optimization of education and its increased focus on the creative development of children and teenagers. Methods. Author uses the methods of theoretical analysis of original foreign materials; systematization and classification of the data from original foreign sources. Results. The main characteristics of creativity are purposefulness, aiming at search of a new idea or creation of worthy product, and also dependence on the environment that means search of sphere of educational activity for disclosing of individual creative potential of the pupil. Character of creative activity depends on personal characteristics of the performer, the high level of motivation and active use of imagination. Scientific novelty. The main characteristics of creative activity as seen by British educators are specified, particularly such feature as dependence on the environment is exposed, and the importance of using traditional teaching methods within the innovative ones is proved; the methods of teaching creativity used by British teachers are picked out and classified according to the levels of creative activity; practical recommendations for successful implementation of teaching creativity are described, such as taking advantage of spontaneous educational situations and the following changes in the work agenda. Practical significance. Analysis and systematization of the foreign researchers’ experience enriches Russian theory of education with understanding the fundamentals of teaching creativity. The singled out peculiarities of teaching creativity give perspectives for the scientific substantiation of adaption of the innovative components into Russian system of

  10. Evaluation of surficial sediment toxicity and sediment physico-chemical characteristics of representative sites in the Lagoon of Venice (Italy) (United States)

    Losso, C.; Arizzi Novelli, A.; Picone, M.; Marchetto, D.; Pessa, G.; Molinaroli, E.; Ghetti, P. F.; Volpi Ghirardini, A.


    Toxic hazard in sites with varying types and levels of contamination in the Lagoon of Venice was estimated by means of toxicity bioassays based on the early life-stages of the autochthonous sea urchin Paracentrotus lividus. Elutriate was chosen as the test matrix, due to its ability to highlight potential toxic effects towards sensitive biological components of the water column caused by sediment resuspension phenomena affecting the Lagoon. Surficial sediments (core-top 5 cm deep), directly influenced by resuspension/redeposition processes, and core sediments (core 20 cm deep), recording time-mediated contamination, were sampled in some sites located in the lagoonal area most greatly influenced by anthropogenic activities. Particle size, organic matter and water content were also analysed. In two sites, the results of physical parameters showed that the core-top sediments were coarser than the 20-cm core sediments. Sperm cell toxicity test results showed the negligible acute toxicity of elutriates from all investigated sites. The embryo toxicity test demonstrated a short-term chronic toxicity gradient for elutriates from the 20-cm core sediments, in general agreement both with the expected contamination gradient and with results of the Microtox® solid-phase test. Elutriates of the core-top 5-cm sediments revealed a totally inverted gradient, in comparison with that for the 20-cm core sediments, and the presence of a "hot spot" of contamination in the site chosen as a possible reference. Investigations on ammonia and sulphides as possible confounding factors excluded their contribution to this "hot spot". Integrated physico-chemical and toxicity results on sediments at various depths demonstrated the presence of disturbed sediments in the central basin of the Lagoon of Venice.

  11. Assessment of Cost Impacts of Using Non-Toxic Propulsion in Satellites (United States)

    Schiebener, P. J.; Gies, O.; Stuhlberger, J.; Schmitz, H.-D.


    The growing costs of space missions, the need for increased mission performance, and concerns associated with environmental issues deeply influence propulsion system design and propellant selection criteria. A propellant's performance was defined in the past exclusively in terms of specific impulse and density, but now high-performance, non-toxic, non-sophisticated mono- propellant systems are key drivers, and are considered for development to replace the traditional hydrazine (N2H4) mono-propellant thrusters. The mono-propellants under consideration are propellant formulations, which should be environmentally friendly, should have a high density, equal or better performance and better thermal characteristics than hydrazine. These considerations raised interest specially in the candidates of Hydroxylammonium Nitrate (HAN)-based propellants, Ammoniumdinitramide (ADN)-based propellants, Tri-ethanol (TEAN)-based propellants, Hydrazinium Nitroformate (HNF)-based propellants, Hydrogen Peroxide (H2O2)-based propellants. A near-term objective in consideration of satellite related process optimisation is to significantly reduce on-ground operations costs and at the same time improve mission performance. A far-term objective is to obtain a system presenting a very high performance, illustrated by a high specific impulse. Moving to a "non-toxic" propulsion system seems to be a solution to these two goals. The sought after benefits for non-toxic spacecraft mono-propellant propulsion are under investigation taking into account the four main parameters which are mandatory for customer satisfaction while meeting the price constraints: - Reliability, availability, maintainability and safety, - Manufacturing, assembly, integration and test, - Launch preparation and support, - Ground support equipment. These benefits of non-toxic mono-propellants can be proven by various examples, like an expected reduction of development costs due the non-toxicity of propellants which might allow

  12. Leaching characteristics of copper flotation waste before and after vitrification. (United States)

    Coruh, Semra; Ergun, Osman Nuri


    Copper flotation waste from copper production using a pyrometallurgical process contains toxic metals such as Cu, Zn, Co and Pb. Because of the presence of trace amounts of these highly toxic metals, copper flotation waste contributes to environmental pollution. In this study, the leaching characteristics of copper flotation waste from the Black Sea Copper Works in Samsun, Turkey have been investigated before and after vitrification. Samples obtained from the factory were subjected to toxicity tests such as the extraction procedure toxicity test (EP Tox), the toxicity characteristic leaching procedure (TCLP) and the "method A" extraction procedure of the American Society of Testing and Materials. The leaching tests showed that the content of some elements in the waste before vitrification exceed the regulatory limits and cannot be disposed of in the present form. Therefore, a stabilization or inertization treatment is necessary prior to disposal. Vitrification was found to stabilize heavy metals in the copper flotation waste successfully and leaching of these metals was largely reduced. Therefore, vitrification can be an acceptable method for disposal of copper flotation waste.

  13. Haloacetonitriles: metabolism and toxicity. (United States)

    Lipscomb, John C; El-Demerdash, Ebtehal; Ahmed, Ahmed E


    bioactivation process, depending on the particular HAN and the enzyme involved. HANs can inhibit CYP2E1-mediated metabolism, an effect which may be dependent on a covalent interaction with the enzyme. In addition, HAN compounds inhibit GST-mediated conjugation, but this effect is reversible upon dialysis, indicating that the interaction does not represent covalent binding. No subchronic studies of HAN toxicity are available in the literature. However, studies show that HANs produce developmental toxicity in experimental animals. The nature of developmental toxicity is affected by the type of administration vehicle, which renders interpretation of results more difficult. Skin tumors have been found following dermal application of HANs, but oral studies for carcinogenicity are negative. Pulmonary adenomas were increased following oral administration of HANs, but the A/J strain of mice employed has a characteristically high background rate of such tumors. HANs interact with DNA to produce unscheduled DNA repair, SCE and reverse mutations in Salmonella. HANs did not induce micronuclei or cause alterations in sperm head morphology in mice, but did induce micronuclei in newts. Thus, there is concern for the potential carcinogenicity of HANs. It would be valuable to delineate any relationship between the apparent threshold for micronuclei formation in newts and the potential mechanism of toxicity involving HAN-induced oxidative stress. Dose-response studies in rodents may provide useful information on toxicity mechanisms and dose selection for longer term toxicity studies. Additional studies are warranted before drawing firm conclusions on the hazards of HAN exposure. Moreover, additional studies on HAN-DNA and HAN-protein interaction mechanisms, are needed. Such studies can better characterize the role of metabolism in toxicity of individual HANs, and delineate the role of oxidative stress, both of which enhance the capacity to predict risk. Most needed, now, are new subchronic (and

  14. Where Learners' Questions Meet Modes of Teaching: A Study of Cases (United States)

    de Jesus, Helena Pedrosa; Almeida, Patricia; Teixeira-Dias, Jose J.; Watts, Mike


    This paper is concerned with "match-mismatch" problems. In particular it seeks to match students' questioning to different modes of teaching in undergraduate chemistry. Kolb's theory of experiential learning is used to bridge between learners' questioning and teaching formats. Three case studies illuminate both sets of characteristics, the…

  15. Teaching for excellence: honors pedagogies revealed

    NARCIS (Netherlands)

    Wolfensberger, M.V.C.


    What are characteristics of honors pedagogies in higher education? What are the teaching strategies that are particularly relevant and successful for academically gifted and motivated students? In spite of the substantial body of literature about the practice of honors education, very little

  16. Developmental toxicity of engineered nanomaterials

    DEFF Research Database (Denmark)

    Hougaard, Karin S.; Hansen, Jitka S.; Jackson, Petra


    Study of air pollution indicates that minute particles may adversely interfere with pregnancy and fetal development. As engineering of nanoparticles have emerged, so has concern that these might interfere with reproductive and developmental functions. This is because nanotechnology may potentially...... increase the overall particle burden in air and introduce particles with novel characteristics and surface reactivity. To evaluate safety for pregnant women, we have studied developmental toxicity of engineered nanoparticles (ENPs), following exposure of pregnant mice by inhalation (ENPs of titanium...

  17. Hazardous and toxic waste management in Botswana: practices and challenges. (United States)

    Mmereki, Daniel; Li, Baizhan; Meng, Liu


    Hazardous and toxic waste is a complex waste category because of its inherent chemical and physical characteristics. It demands for environmentally sound technologies and know-how as well as clean technologies that simultaneously manage and dispose it in an environmentally friendly way. Nevertheless, Botswana lacks a system covering all the critical steps from importation to final disposal or processing of hazardous and toxic waste owing to limited follow-up of the sources and types of hazardous and toxic waste, lack of modern and specialised treatment/disposal facilities, technical know-how, technically skilled manpower, funds and capabilities of local institutions to take lead in waste management. Therefore, because of a lack of an integrated system, there are challenges such as lack of cooperation among all the stakeholders about the safe management of hazardous and toxic waste. Furthermore, Botswana does not have a systematic regulatory framework regarding monitoring and hazardous and toxic waste management. In addition to the absence of a systematic regulatory framework, inadequate public awareness and dissemination of information about hazardous and toxic waste management, slower progress to phase-out persistent and bio-accumulative waste, and lack of reliable and accurate information on hazardous and toxic waste generation, sources and composition have caused critical challenges to effective hazardous and toxic waste management. It is, therefore, important to examine the status of hazardous and toxic waste as a waste stream in Botswana. By default; this mini-review article presents an overview of the current status of hazardous and toxic waste management and introduces the main challenges in hazardous and toxic waste management. Moreover, the article proposes the best applicable strategies to achieve effective hazardous and toxic waste management in the future. © The Author(s) 2014.

  18. Chronic Dermal Toxicity of Epoxy Resins I. Skin Carcinogenic Potency and General Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Holland, J.M.


    Epoxy resins are a diverse class of chemicals that differ in structure, physical properties, and, presumably, biological activity. The purpose of these experiments was to compare the chronic dermal toxicity and carcinogenicity of selected commercial epoxy resins and to determine the potential for positive synergistic carcinogenic interactions between different resins. This work is an extension and continuation of a Department of Energy sponsored program to evaluate epoxy resins for potential occupational health risks. The materials examined were chosen on the basis of their interest to the U.S. government. They are representative of the manufacturer's production at the time, and therefore the data are completely valid only for the specific production period. Results of the experimental exposures will be reported in two parts. This report describes the test materials, their chemical and physical characteristics and the experimental design. General (systemic) toxicity will be evaluated and the skin carcinogenicity of the materials compared. A subsequent report will provide morphological descriptions of skin and significant internal pathology induced by the various treatments.

  19. Toxicity of cassava wastewater effluents to African catfish: Clarias ...

    African Journals Online (AJOL)

    The relative lethal and sublethal toxicity of cassava wastewater effluents from a local food factory were investigated on Clarias gariepinus fingerlings using a renewable static bioassay. The physico-chemical characteristics of the cassava wastewater effluents showed a number of deviations from the standards of the Federal ...

  20. Characteristics of several equilibrium fuel cycles of PWR

    International Nuclear Information System (INIS)

    Waris, Abdul; Sekimoto, Hiroshi


    This paper evaluated the influence of neutron spectrum on characteristics of several equilibrium fuel cycles of pressurized water reactor (PWR). In this study, five kinds of fuel cycles were investigated. Required uranium enrichment, required natural uranium amount, and toxicity of heavy metals (HMs) in spent fuel were presented for comparison. The results showed that the enrichment and the required amount of natural uranium decrease significantly with increasing number of confined heavy nuclides when uranium is discharged from the reactor. On the other hand, when uranium is totally confined, the enrichment becomes extremely high. The confinement of plutonium and minor actinides (MA) seems effective in reducing radio-toxicity of discharged wastes. By confining all heavy nuclides except uranium those three characteristics could be reduced considerably. For this fuel cycle the toxicity of HMs in spent fuel become nearly equal to or less than that of loaded uranium. (author)

  1. Toxicity identification evaluation methods for identification of toxicants in refinery effluents

    International Nuclear Information System (INIS)

    Barten, K.A.; Mount, D.R.; Hackett, J.R.


    During the last five years, the authors have used Toxicity Identification Evaluation (TIE) methods to characterize and identify the source(s) of toxicity in effluents from dozens of municipal and industrial facilities. In most cases, specific chemicals responsible for toxicity have been identified. Although generally successful, the initial experience was that for several refinery effluents, they were able only to qualitatively characterize the presence of organic toxicants; standard toxicant identification procedures were not able to isolate specific organic chemicals. They believe that organic toxicity in these refinery effluents is caused by multiple organic compounds rather than by just a few; evidence for this includes an inability to isolate toxicity in a small number of fractions using liquid chromatography and the presence of very large numbers of compounds in isolated fractions. There is also evidence that the toxicant(s) may be ionic, in that the toxicity of whole effluent and isolated fractions often show increasing toxicity with decreasing pH. Finally, positive-pressure filtration has also reduced toxicity in some samples. In this presentation the authors summarize their experiences with refinery effluents, focusing on typical patterns they have observed and alternative procedures they have used to better understand the nature of these toxicants

  2. Factors affecting toxicity and efficacy of polymeric nanomedicines

    International Nuclear Information System (INIS)

    Igarashi, Eiki


    Nanomedicine is the application of nanotechnology to medicine. The purpose of this article is to review common characteristics of polymeric nanomedicines with respect to passive targeting. We consider several biodegradable polymeric nanomedicines that are between 1 and 100 nm in size, and discuss the impact of this technology on efficacy, pharmacokinetics, toxicity and targeting. The degree of toxicity of polymeric nanomedicines is strongly influenced by the biological conditions of the local environment, which influence the rate of degradation or release of polymeric nanomedicines. The dissemination of polymeric nanomedicines in vivo depends on the capillary network, which can provide differential access to normal and tumor cells. The accumulation of nanomedicines in the microlymphatics depends upon retention time in the blood and extracellular compartments, as well as the type of capillary endothelium surrounding specific tissues. Finally, the toxicity or efficacy of intact nanomedicines is also dependent upon tissue type, i.e., non-endocrine or endocrine tissue, spleen, or lymphatics, as well as tumor type


    Directory of Open Access Journals (Sweden)

    Iryna Lobachova


    Full Text Available The article deals with the problem of the application of the associative teaching technology at primary school and the peculiarities of its implementation in teaching English to primary schoolchildren. It is found out that the modern primary school student should be able to think creatively, to solve given tasks, find associative links between objects, and be able to intercultural communication. So, a teacher has to master the innovative teaching technologies that optimize and intensify the educational process to forming primary schoolchildren’s abilities of this kind. It is determined that the technology of associative teaching English to primary schoolchildren is one of the most effective technologies because it meets quite new goals and tasks of teaching foreign languages at primary school, age and individual characteristics, needs, and interests of primary schoolchildren. It is shown that the associative teaching technology is based on the principle of harmony with nature and it creates conditions that are close to life situations, makes learning the foreign language accessible and relaxed. Associative teaching a foreign language and its various aspects are performed in accordance with the primary schoolchildren’s individual characteristics. The psychological mechanism is very important in the organization of associative teaching; it is taken into account in teaching children of primary school because human beings think with images and words are sound images that allow you to express what a person sees, feels, and thinks. Associative teaching combines both verbal and non-verbal means of communication. Associative teaching contributes to learning a foreign language based on the child’s real actions in the form of the active actions with items in accordance with the human linguistic programme that defines phased sequence of the language development. An effective method of teaching a foreign language is a method of Mind Mapping, which

  4. Comparison of cellular toxicity between multi-walled carbon nanotubes and onion-like shell-shaped carbon nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seunghyon [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of); Kim, Ji-Eun [Korea Research Institute of Standard and Science, Center for NanoSafety Metrology, Division of Convergence Technology (Korea, Republic of); Kim, Daegyu [LG Electronics (Korea, Republic of); Woo, Chang Gyu [Korea Institute of Machinery and Materials, Environmental and Energy Systems Research Division (Korea, Republic of); Pikhitsa, Peter V. [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of); Cho, Myung-Haing, E-mail: [Seoul National University, Laboratory of Toxicology, College of Veterinary Medicine (Korea, Republic of); Choi, Mansoo, E-mail: [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of)


    The cellular toxicity of multi-walled carbon nanotubes (MWCNTs) and onion-like shell-shaped carbon nanoparticles (SCNPs) was investigated by analyzing the comparative cell viability. For the reasonable comparison, physicochemical characteristics were controlled thoroughly such as crystallinity, carbon bonding characteristic, hydrodynamic diameter, and metal contents of the particles. To understand relation between cellular toxicity of the particles and generation of reactive oxygen species (ROS), we measured unpaired singlet electrons of the particles and intracellular ROS, and analyzed cellular toxicity with/without the antioxidant N-acetylcysteine (NAC). Regardless of the presence of NAC, the cellular toxicity of SCNPs was found to be lower than that of MWCNTs. Since both particles show similar crystallinity, hydrodynamic size, and Raman signal with negligible contribution of remnant metal particles, the difference in cell viability would be ascribed to the difference in morphology, i.e., spherical shape (aspect ratio of one) for SCNP and elongated shape (high aspect ratio) for MWCNT.

  5. Comparison of cellular toxicity between multi-walled carbon nanotubes and onion-like shell-shaped carbon nanoparticles

    International Nuclear Information System (INIS)

    Kang, Seunghyon; Kim, Ji-Eun; Kim, Daegyu; Woo, Chang Gyu; Pikhitsa, Peter V.; Cho, Myung-Haing; Choi, Mansoo


    The cellular toxicity of multi-walled carbon nanotubes (MWCNTs) and onion-like shell-shaped carbon nanoparticles (SCNPs) was investigated by analyzing the comparative cell viability. For the reasonable comparison, physicochemical characteristics were controlled thoroughly such as crystallinity, carbon bonding characteristic, hydrodynamic diameter, and metal contents of the particles. To understand relation between cellular toxicity of the particles and generation of reactive oxygen species (ROS), we measured unpaired singlet electrons of the particles and intracellular ROS, and analyzed cellular toxicity with/without the antioxidant N-acetylcysteine (NAC). Regardless of the presence of NAC, the cellular toxicity of SCNPs was found to be lower than that of MWCNTs. Since both particles show similar crystallinity, hydrodynamic size, and Raman signal with negligible contribution of remnant metal particles, the difference in cell viability would be ascribed to the difference in morphology, i.e., spherical shape (aspect ratio of one) for SCNP and elongated shape (high aspect ratio) for MWCNT

  6. Effects of water quality parameters on boron toxicity to Ceriodaphnia dubia. (United States)

    Dethloff, Gail M; Stubblefield, William A; Schlekat, Christian E


    The potential modifying effects of certain water quality parameters (e.g., hardness, alkalinity, pH) on the acute toxicity of boron were tested using a freshwater cladoceran, Ceriodaphnia dubia. By comparison, boron acute toxicity was less affected by water quality characteristics than some metals (e.g., copper and silver). Increases in alkalinity over the range tested did not alter toxicity. Increases in water hardness appeared to have an effect with very hard waters (>500 mg/L as CaCO(3)). Decreased pH had a limited influence on boron acute toxicity in laboratory waters. Increasing chloride concentration did not provide a protective effect. Boron acute toxicity was unaffected by sodium concentrations. Median acute lethal concentrations (LC(50)) in natural water samples collected from three field sites were all greater than in reconstituted laboratory waters that matched natural waters in all respects except for dissolved organic carbon. Water effect ratios in these waters ranged from 1.4 to 1.8. In subsequent studies using a commercially available source of natural organic matter, acute toxicity decreased with increased dissolved organic carbon, suggesting, along with the natural water studies, that dissolved organic carbon should be considered further as a modifier of boron toxicity in natural waters where it exceeds 2 mg/L.

  7. Phenological Characteristics of the Barred Chicken in Western ...

    African Journals Online (AJOL)

    Between May and June 2011, the growth performance and phenological characteristics of local barred chicken of the Western Highland Cameroon was carried out in the Teaching and Research Farm of the University of Dschang. The data on body weight, body measurements and carcass characteristics were collected on ...

  8. Handbook for Teaching Korean-American Students. (United States)

    California State Dept. of Education, Sacramento. Bilingual Education Office.

    This handbook is designed for teachers, administrators, and other school personnel. It provides an explanation of the sociocultural and linguistic characteristics of Korean-Americans so educators can address their needs more effectively and orchestrate a better teaching environment by understanding and supporting the Korean-American cultural…

  9. Teaching Bird Identification & Vocabulary with Twitter (United States)

    Hallman, Tyler A.; Robinson, W. Douglas


    Species identification is essential to biology, conservation, and management. The ability to focus on specific diagnostic characteristics of a species helps improve the speed and accuracy of identification. Birds are excellent subjects for teaching species identification because, in combination with their different shapes and sizes, their plumages…

  10. Introducing Toxics


    David C. Bellinger


    With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present ...

  11. Toxic shock syndrome (United States)

    Staphylococcal toxic shock syndrome; Toxic shock-like syndrome; TSLS ... Toxic shock syndrome is caused by a toxin produced by some types of staphylococcus bacteria. A similar problem, called toxic shock- ...

  12. The Development and Preliminary Application Ofplant Quarantine Remote Teaching System Inchina (United States)

    Wu, Zhigang; Li, Zhihong; Yang, Ding; Zhang, Guozhen

    With the development of modern information technology, the traditional teaching mode becomes more deficient for the requirement of modern education. Plant Quarantine has been accepted as the common course for the universities of agriculture in China after the entry of WTO. But the teaching resources of this course are not enough especially for most universities with lack base. The characteristic of e-learning is regarded as one way to solve the problem of short teaching resource. PQRTS (Plant Quarantine Remote Teaching System) was designed and developed with JSP (Java Sever Pages), MySQL and Tomcat in this study. The system included many kinds of plant quarantine teaching resources, such as international glossary, regulations and standards, multimedia information of quarantine process and pests, ppt files of teaching, and training exercise. The system prototype implemented the functions of remote learning, querying, management, examination and remote discussion. It could be a tool for teaching, teaching assistance and learning online.

  13. Time-response characteristic and potential biomarker identification of heavy metal induced toxicity in zebrafish. (United States)

    Yin, Jian; Wang, Ai-Ping; Li, Wan-Fang; Shi, Rui; Jin, Hong-Tao; Wei, Jin-Feng


    The present work aims to explore the time-response (from 24 h to 96 h) characteristic and identify early potential sensitive biomarkers of copper (Cu) (as copper chloride dihydrate), cadmium (Cd) (as cadmium acetate), lead (Pb) (as lead nitrate) and chromium (Cr) (as potassium dichromate) exposure in adult zebrafish, focusing on reactive oxygen species (ROS), SOD activity, lipid peroxidation and gene expression related to oxidative stress and inflammatory response. Furthermore, the survival rate decreased apparently by a concentration-dependent manner after Cu, Cr, Cd and Pb exposure, and we selected non-lethal concentrations 0.05 mg/L for Cu, 15 mg/L for Cr, 3 mg/L for Cd and 93.75μg/L for Pb to test the effect on the following biological indicators. Under non-lethal concentration, the four heavy metals have no apparent histological change in adult zebrafish gills. Similar trends in ROS production, MDA level and SOD activity were up-regulated by the four heavy metals, while MDA level responded more sensitive to Pb by time-dependent manner than the other three heavy metals. In addition, mRNA levels related to antioxidant system (SOD1, SOD2 and Nrf2) were up-regulated by non-lethal concentration Cu, Cr, Cd and Pb exposure. MDA level and SOD1 gene have a more delayed response to heavy metals. Genes related to immunotoxicity were increased significantly after heavy metals exposure at non-lethal concentrations. TNF-α and IL-1β gene have similar sensibility to the four heavy metals, while IL-8 gene was more responsive to Cr, Cd and Pb exposure at 48 h groups and IFN-γ gene showed more sensitivity to Cu at 48 h groups than the other heavy metals. In conclusion, the present works have suggested that the IFN-γ gene may applied as early sensitive biomarker to identify Cu-induced toxicity, while MDA content and IL-8 gene may use as early sensitive biomarkers for evaluating the risk of Pb exposure. Moreover, IL-8 and IFN-γ gene were more responsive to heavy

  14. An Investigation into the Characteristics of Iranian EFL Teachers of Senior Secondary Schools and Language Institutes (United States)

    Afshar, Hassan Soodmand; Hamzavi, Raouf


    The present study explored the characteristics of 147 Iranian EFL teachers teaching at senior secondary schools (N = 62) and those teaching in private language institutes (N = 85). Data were collected through a Likert-scale teacher characteristics questionnaire mainly adapted from Borg (2006). Also, for data triangulation purposes, 20 teachers…

  15. Learning to Teach Geography for Primary Education: Results of an Experimental Programme (United States)

    Blankman, Marian; Schoonenboom, Judith; van der Schee, Joop; Boogaard, Marianne; Volman, Monique


    Students training to become primary school teachers appear to have little awareness of the core concepts of geography (teaching). To ensure that future primary school teachers are able to develop their pupils' geographical awareness, a six weeks programme was developed. The characteristics of this programme -- named Consciously Teaching Geography…

  16. Matching Student Expectations with Instructors' Dispositions: Insight into Quality of Online Teaching (United States)

    Welch, Anita G.; Orso, Don; Doolittle, Joan; Areepattamannil, Shaljan


    This paper explores the similarities and differences between student expectations of online instructors and the teaching dispositions of online instructors. Our research goal is to develop insight into factors related to online student success. Although researchers have identified key characteristics of effective teaching in the face-to-face…

  17. A study on the toxicity of three radiosensitizers on retinoblastoma cells by MTT assay

    International Nuclear Information System (INIS)

    Yi Xianjin; Jin Yizun; Ding Li; Ni Zhou; Wang Wenji


    The toxicity of three radiosensitizers BSO, CM and RSU-1069 on retinoblastoma cells was determined and the efficiency of in vitro MTT assay on drug-screening for retinoblastoma was also evaluated. The results showed that the MTT assay is very useful. The toxicity of radiosensitizers on retinoblastoma cells is dependent on cell line characteristics, drug concentration and time of exposure to it

  18. Anaerobic biodegradability and toxicity of complex or toxicant wastewater

    International Nuclear Information System (INIS)

    Wills Betancur, B.A.


    As a first approximation to wastewater classification in susceptibility terms to treatment by anaerobic biological system, anaerobic biodegradability trials are accomplished to leached of sanitary landfill, to wastewater of coffee grain wet treatment plant and to wastewater of fumaric acid recuperation plant. In the last Plant, anaerobic toxicity trials and lethal toxicity on the Daphnia pulex micro-crustacean are made too. Anaerobic biological trials are made continuing the Wageningen University (Holland) Methodology (1.987). Lethal toxicity biological trials are made following the Standard Methods for the Examination of Water and Wastewater(18th edition, 1992). In development of this investigation project is found that fumaric acid recuperation plant leached it has a low anaerobic biodegradability, a high anaerobic toxicity and a high lethal toxicity over Daphnia pulex, for such reasons this leached is cataloged as complex and toxic wastewater. The other hand, wastewater of coffee grain wet treatment plant and wastewater of sanitary landfill they are both highly biodegradability and not-toxic, for such reasons these wastewaters are cataloged as susceptible to treatment by anaerobic biological system

  19. Parents of children with physical disabilities perceive that characteristics of home exercise programs and physiotherapists' teaching styles influence adherence: a qualitative study. (United States)

    Lillo-Navarro, Carmen; Medina-Mirapeix, Francesc; Escolar-Reina, Pilar; Montilla-Herrador, Joaquina; Gomez-Arnaldos, Francisco; Oliveira-Sousa, Silvana L


    What are the perceptions of parents of children with physical disabilities about the home exercise programs that physiotherapists prescribe? How do these perceptions affect adherence to home exercise programs? Qualitative study using focus groups and a modified grounded theory approach. Parents of children with physical disabilities who have been prescribed a home exercise program by physiotherapists. Twenty-eight parents participated in the focus groups. Two key themes that related to adherence to home exercise programs in young children with physical disabilities were identified: the characteristics of the home exercise program; and the characteristics of the physiotherapist's teaching style. In the first theme, the participants described their experiences regarding their preference for exercises, which was related to the perceived effects of the exercises, their complexity, and the number of exercises undertaken. These factors determined the amount of time spent performing the exercises, the effect of the exercises on the family's relationships, and any sense of related burden. In the second theme, participants revealed that they adhered better to prescribed exercises when their physiotherapist made an effort to build their confidence in the exercises, helped the parents to incorporate the home exercise program into their daily routine, provided incentives and increased motivation. Parents perceive that their children's adherence to home-based exercises, which are supervised by the parents, is more successful when the physiotherapist's style and the content of the exercise program are positively experienced. These findings reveal which issues should be considered when prescribing home exercise programs to children with physical disabilities. [Lillo-Navarro C, Medina-Mirapeix F, Escolar-Reina P, Montilla-Herrador J, Gomez-Arnaldos F, Oliveira-Sousa SL (2015) Parents of children with physical disabilities perceive that characteristics of home exercise programs and

  20. Teaching strategies in web technologies for virtual learning environments

    Directory of Open Access Journals (Sweden)

    Ilber Dario Saza-Garzón


    Full Text Available The virtual learning environments (AVAs have been a subject of discussion and questions mainly on finding the best teaching practices, which tools you can use them and how to achieve optimum utilization have better results in virtual education, for Therefore in this paper some elements about the characteristics, history, teaching, studies have virtual environments and web applications as tools to support teaching and learning, are set for a virtual tutor note the when planning, designing, creating and implementing online courses. Thus the reader will find concepts, explanations and different evolutionary processes that wins ICT and how are you have been involved in the educational context, spotting potential applications from mediation of teaching, plus some suggestions of how to carry out exposed use thereof in virtual learning environments to strengthen the different processes of teaching and learning.

  1. Measuring financial toxicity as a clinically relevant patient-reported outcome: The validation of the COmprehensive Score for financial Toxicity (COST). (United States)

    de Souza, Jonas A; Yap, Bonnie J; Wroblewski, Kristen; Blinder, Victoria; Araújo, Fabiana S; Hlubocky, Fay J; Nicholas, Lauren H; O'Connor, Jeremy M; Brockstein, Bruce; Ratain, Mark J; Daugherty, Christopher K; Cella, David


    Cancer and its treatment lead to increased financial distress for patients. To the authors' knowledge, to date, no standardized patient-reported outcome measure has been validated to assess this distress. Patients with AJCC Stage IV solid tumors receiving chemotherapy for at least 2 months were recruited. Financial toxicity was measured by the COmprehensive Score for financial Toxicity (COST) measure. The authors collected data regarding patient characteristics, clinical trial participation, health care use, willingness to discuss costs, psychological distress (Brief Profile of Mood States [POMS]), and health-related quality of life (HRQOL) as measured by the Functional Assessment of Cancer Therapy: General (FACT-G) and the European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaires. Test-retest reliability, internal consistency, and validity of the COST measure were assessed using standard-scale construction techniques. Associations between the resulting factors and other variables were assessed using multivariable analyses. A total of 375 patients with advanced cancer were approached, 233 of whom (62.1%) agreed to participate. The COST measure demonstrated high internal consistency and test-retest reliability. Factor analyses revealed a coherent, single, latent variable (financial toxicity). COST values were found to be correlated with income (correlation coefficient [r] = 0.28; Pfinancial toxicity were race (P = .04), employment status (Pcosts was not found to be associated with the degree of financial distress (P = .49). The COST measure demonstrated reliability and validity in measuring financial toxicity. Its correlation with HRQOL indicates that financial toxicity is a clinically relevant patient-centered outcome. Cancer 2017;123:476-484. © 2016 American Cancer Society. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

  2. An Analytical Hierarchy Process Model for the Evaluation of College Experimental Teaching Quality (United States)

    Yin, Qingli


    Taking into account the characteristics of college experimental teaching, through investigaton and analysis, evaluation indices and an Analytical Hierarchy Process (AHP) model of experimental teaching quality have been established following the analytical hierarchy process method, and the evaluation indices have been given reasonable weights. An…

  3. Design of the Model of Constructivist Learning Theory for Moral Education in Physical Education Teaching (United States)

    Wang, Chenyu


    In order to achieve better effect of moral education in physical education teaching, this article employed constructivist learning theory to design the model of moral education according to the characteristics of physical education teaching, in order that the majority of P.E. teachers draw lessons from it in their teaching practice, and service to…


    Directory of Open Access Journals (Sweden)

    Mariia Kuts


    Full Text Available Modern learning foreign languages is based on a humanistic paradigm. The realization of the possibility of such activity researches consider in implementation of technological approach in educational process. The scientists connect the optimal and qualitative realization of this activity with the implementation of education technology into learning process. Modern studies are focused on questions of implementation of technological approach into teaching foreign languages. It is thought to allow to achieve guaranteed minimal level of learning results. At the same time there are some incompletely studied aspects such as content of pedagogical technologies, their conceptual and procedural characteristics, approaches to classification. In the article the essence of technological approach is revealed, the communicatively focused technologies of teaching foreign languages in non-linguistic universities are concretized. The interpretation of technological approach is given; characteristics and attributes in teaching foreign languages are selected. It is noticed that technological approach is social and engineering ideology in the sphere of didactics according to which teaching process is considered to be a completely designed process with strictly planned and fixed results (M. Klarin. In the article it is emphasized on feasibility and efficiency of technological approach while teaching foreign languages, the degree of its integration in educational process is defined. The communication-oriented technologies, based on a communicative method of E. Passov, are allocated as the most optimum. It is shown the communication-oriented technologies go beyond the conceptual idea of modelling in teaching process of real foreign-language communication, and their procedural component and contents are founded on certain principles. The most commonly used technologies of teaching foreign languages are classified as technologies of modernization and technologies of

  5. Teaching Teaching & Understanding Understanding

    DEFF Research Database (Denmark)


    "Teaching Teaching & Understanding Understanding" is a 19-minute award-winning short-film about teaching at university and higher-level educational institutions. It is based on the "Constructive Alignment" theory developed by Prof. John Biggs. The film delivers a foundation for understanding what...

  6. Determination of Leacheability of U, Th and Heavy Metals of Water Leached Purification (WLP) Residue and Soil from Bauxite Mining Area using Toxicity Characteristic Leaching Technique

    International Nuclear Information System (INIS)

    Siti Aminah Omar; Suhaimi Hamzah; Shamsiah Abdul Rahman


    The study was conducted to analyse the leachability of U, Th and heavy metals Cu, Cd, As, Pb, Mn, Zn, Ba, Se, Cr and Fe of water leached purification (WLP) residue gathered from Lynas Malaysia Sdn Bhd and soil from bauxite mining area, Kuantan. Their toxicity was assessed using the toxicity characteristic leaching procedure (TCLP) developed by the United States Environmental Protection Agency. The concentration of the elements studied was analysed using inductively coupled plasma mass spectrometry (ICP-MS). Results from the analysis indicated that the concentrations for all the elements studied in this project are well below than the TCLP regulatory limit. The concentrations of U and Th in leached solution were between 0.01 - 0.20 Bq/ kg. The concentrations of the multi elements were mostly between 0.02 - 1471 μg/ l, but certain elements such as Fe had concentration as high as 4707 μg/ l. Hence, it can be concluded that the WLP residue from Lynas and soil from bauxite mining area are very stable in the environment and does not pose any environmental problem. (author)

  7. Liking a tough teacher : Interpersonal characteristics of teaching and students’ achievement goals

    NARCIS (Netherlands)

    Mainhard, Tim


    Many have claimed, but only some have shown, that the social nature of teaching and classrooms is likely to have a direct effect on students’ achievement goals. This study examined the extent to which Dutch secondary school students’ (N = 2892) achievement goals were related to the interpersonal

  8. The Student Teachers Perceptions On Teaching Practice Supervision In Zimbabwe Is It A Process Of Grading Or Improvement Of Teaching Skills

    Directory of Open Access Journals (Sweden)

    Dr Sylod Chimhenga


    Full Text Available Supervisors are expected to observe how student teachers prepare deliver the lesson and conduct themselves as members of teaching profession and are expected to advise the students on how to improve their teaching skills. The present study is a descriptive survey which sought to analyze student teachers perception towards teaching practice as an exercise for grading or improvement and examine student teachers perception towards student-supervisor comments during discussion after classroom assessment. The sample comprised of 50 second year Diploma in Education who had undergone teaching practice in 2016. The students were purposefully sampled. In purposeful sampling the researcher selects the participants because they possess particular characteristics or knowledge being sought. A questionnaire was used to collect data for this study. The findings indicated that majority of student teachers who participated in the teaching practice perceived that the supervisors gave grades which did not reflect the comments made about the teaching performance of the student teacher. Based on the findings recommendations were made among others that assessment should match the comments on areas needing improvement and meaningful accompanying comments should be made to guide student teachers in the desired directions during teaching practice encourage student teachers to try harder or to give credit for work done well.

  9. Experimental investigation of the catalytic decomposition and combustion characteristics of a non-toxic ammonium dinitramide (ADN)-based monopropellant thruster (United States)

    Chen, Jun; Li, Guoxiu; Zhang, Tao; Wang, Meng; Yu, Yusong


    Low toxicity ammonium dinitramide (ADN)-based aerospace propulsion systems currently show promise with regard to applications such as controlling satellite attitude. In the present work, the decomposition and combustion processes of an ADN-based monopropellant thruster were systematically studied, using a thermally stable catalyst to promote the decomposition reaction. The performance of the ADN propulsion system was investigated using a ground test system under vacuum, and the physical properties of the ADN-based propellant were also examined. Using this system, the effects of the preheating temperature and feed pressure on the combustion characteristics and thruster performance during steady state operation were observed. The results indicate that the propellant and catalyst employed during this work, as well as the design and manufacture of the thruster, met performance requirements. Moreover, the 1 N ADN thruster generated a specific impulse of 223 s, demonstrating the efficacy of the new catalyst. The thruster operational parameters (specifically, the preheating temperature and feed pressure) were found to have a significant effect on the decomposition and combustion processes within the thruster, and the performance of the thruster was demonstrated to improve at higher feed pressures and elevated preheating temperatures. A lower temperature of 140 °C was determined to activate the catalytic decomposition and combustion processes more effectively compared with the results obtained using other conditions. The data obtained in this study should be beneficial to future systematic and in-depth investigations of the combustion mechanism and characteristics within an ADN thruster.

  10. Beyond Bigotry: Teaching about Unconscious Prejudice (United States)

    Ghoshal, Raj Andrew; Lippard, Cameron; Ribas, Vanesa; Muir, Ken


    Researchers have demonstrated that unconscious prejudices around characteristics such as race, gender, and class are common, even among people who avow themselves unbiased. The authors present a method for teaching about implicit racial bias using online Implicit Association Tests. The authors do not claim that their method rids students of…

  11. Acute gastrointestinal and genitourinary toxicity of image-guided intensity modulated radiation therapy for prostate cancer using a daily water-filled endorectal balloon

    Directory of Open Access Journals (Sweden)

    Deville Curtiland


    Full Text Available Abstract Background Our purpose was to report acute gastrointestinal (GI and genitourinary (GU toxicity rates for prostate cancer patients undergoing image-guided intensity modulated radiation therapy (IG-IMRT with a daily endorectal water-filled balloon (ERBH2O, and assess associations with planning parameters and pretreatment clinical characteristics. Methods The first 100 patients undergoing prostate and proximal seminal vesicle IG-IMRT with indexed-lumen 100 cc ERBH2O to 79.2 Gy in 1.8 Gy fractions at our institution from 12/2008- 12/2010 were assessed. Pretreatment characteristics, organ-at-risk dose volume histograms, and maximum GU and GI toxicities (CTCAE 3.0 were evaluated. Logistic regression models evaluated univariate association between toxicities and dosimetric parameters, and uni- and multivariate association between toxicities and pretreatment characteristics. Results Mean age was 68 (range 51–88. Thirty-two, 49, and 19 patients were low, intermediate, and high-risk, respectively; 40 received concurrent androgen deprivation. No grade 3 or greater toxicities were recorded. Maximum GI toxicity was grade 0, 1, and 2 in 69%, 23%, and 8%, respectively. Infield (defined as 1 cm above/below the CTV rectal mean/median doses, D75, V30, and V40 and hemorrhoid history were associated with grade 2 GI toxicity (Ps  Conclusion Prostate IG-IMRT using a daily ERBH2O shows low rates of acute GI toxicity compared to previous reports of air-filled ERB IMRT when using stringent infield rectum constraints and comparable GU toxicities.

  12. Applying the Multisim Technology to Teach the Course of High Frequency Power Amplifier (United States)

    Lv, Gang; Xue, Yuan-Sheng


    As one important professional base course in the electric information specialty, the course of "high frequency electronic circuit" has strong theoretical characteristic and abstract content. To enhance the teaching quality of this course, the computer simulation technology based on Multisim is introduced into the teaching of "high…

  13. Introducing Toxics

    Directory of Open Access Journals (Sweden)

    David C. Bellinger


    Full Text Available With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present their work in as much detail as they wish. Toxics will publish original research papers, conventional reviews, meta-analyses, short communications, theoretical papers, case reports, commentaries and policy perspectives, and book reviews (Book reviews will be solicited and should not be submitted without invitation. Toxins and toxicants concern individuals from a wide range of disciplines, and Toxics is interested in receiving papers that represent the full range of approaches applied to their study, including in vitro studies, studies that use experimental animal or non-animal models, studies of humans or other biological populations, and mathematical modeling. We are excited to get underway and look forward to working with authors in the scientific and medical communities and providing them with a novel venue for sharing their work. [...


    Directory of Open Access Journals (Sweden)

    Olha Homeniuk


    Full Text Available The article investigates the peculiarities of the implementation of the mixed method of teaching English in Bukovyna in the 1930-s highlighting the prerequisites of its application. The analysis of such aspects of the language as phonetics, vocabulary, grammar and types of speaking activity (speaking, reading and writing is carried out based on curricula and textbooks. The paper presents the comparative characteristic of teaching methods of foreign languages in Bukovyna and Halychyna. The approaches and principles of teaching English have been singled out. The basic principles of implementing the mixed method of teaching English in the region have been proved. There have been discovered the interconnected teaching of speech abilities and skills along with, the use of the native language and the importance of teaching grammar and applying intuition and understanding in combination. Theprospects of further research on methods of teaching foreign languages in the territory of Bukovyna have been outlined.


    The mitigating effect of increasing hardness on metal toxicity is reflected in water quality criteria in the United States. - - - Copper toxicity did not consistently vary as a function of hardness, but likely as a function of other water quality characteristics (e.g. alkalinity ...

  16. Late Toxicity After Intensity-Modulated Radiation Therapy for Localized Prostate Cancer: An Exploration of Dose-Volume Histogram Parameters to Limit Genitourinary and Gastrointestinal Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Pederson, Aaron W.; Fricano, Janine; Correa, David; Pelizzari, Charles A. [Department of Radiation and Cellular Oncology, Pritzker School of Medicine, University of Chicago, Chicago, IL (United States); Liauw, Stanley L., E-mail: [Department of Radiation and Cellular Oncology, Pritzker School of Medicine, University of Chicago, Chicago, IL (United States)


    Purpose: To characterize the late genitourinary (GU) and gastrointestinal (GI) toxicity for prostate cancer patients treated with intensity-modulated radiation therapy (IMRT) and propose dose-volume histogram (DVH) guidelines to limit late treatment-related toxicity. Methods and Materials: In this study 296 consecutive men were treated with IMRT for adenocarcinoma of the prostate. Most patients received treatment to the prostate with or without proximal seminal vesicles (90%), to a median dose of 76 Gy. Concurrent androgen deprivation therapy was given to 150 men (51%) for a median of 4 months. Late toxicity was defined by Common Toxicity Criteria version 3.0 as greater than 3 months after radiation therapy completion. Four groupings of DVH parameters were defined, based on the percentage of rectal or bladder tissue receiving 70 Gy (V{sub 70}), 65 Gy (V{sub 65}), and 40 Gy (V{sub 40}). These DVH groupings, as well as clinical and treatment characteristics, were correlated to maximal Grade 2+ GU and GI toxicity. Results: With a median follow-up of 41 months, the 4-year freedom from maximal Grade 2+ late toxicity was 81% and 91% for GU and GI systems, respectively, and by last follow-up, the rates of Grade 2+ GU and GI toxicity were 9% and 5%, respectively. On multivariate analysis, whole-pelvic IMRT was associated with Grade 2+ GU toxicity and age was associated with Grade 2+ GI toxicity. Freedom from Grade 2+ GI toxicity at 4 years was 100% for men with rectal V{sub 70} {<=}10%, V{sub 65} {<=}20%, and V{sub 40} {<=}40%; 92% for men with rectal V{sub 70} {<=}20%, V{sub 65} {<=}40%, and V{sub 40} {<=}80%; and 85% for men exceeding these criteria (p = 0.13). These criteria were more highly associated with GI toxicity in men aged {>=}70 years (p = 0.07). No bladder dose-volume relationships were associated with the risk of GU toxicity. Conclusions: IMRT is associated with low rates of severe GU or GI toxicity after treatment for prostate cancer. Rectal dose constraints

  17. Late Toxicity After Intensity-Modulated Radiation Therapy for Localized Prostate Cancer: An Exploration of Dose–Volume Histogram Parameters to Limit Genitourinary and Gastrointestinal Toxicity

    International Nuclear Information System (INIS)

    Pederson, Aaron W.; Fricano, Janine; Correa, David; Pelizzari, Charles A.; Liauw, Stanley L.


    Purpose: To characterize the late genitourinary (GU) and gastrointestinal (GI) toxicity for prostate cancer patients treated with intensity-modulated radiation therapy (IMRT) and propose dose–volume histogram (DVH) guidelines to limit late treatment-related toxicity. Methods and Materials: In this study 296 consecutive men were treated with IMRT for adenocarcinoma of the prostate. Most patients received treatment to the prostate with or without proximal seminal vesicles (90%), to a median dose of 76 Gy. Concurrent androgen deprivation therapy was given to 150 men (51%) for a median of 4 months. Late toxicity was defined by Common Toxicity Criteria version 3.0 as greater than 3 months after radiation therapy completion. Four groupings of DVH parameters were defined, based on the percentage of rectal or bladder tissue receiving 70 Gy (V 70 ), 65 Gy (V 65 ), and 40 Gy (V 40 ). These DVH groupings, as well as clinical and treatment characteristics, were correlated to maximal Grade 2+ GU and GI toxicity. Results: With a median follow-up of 41 months, the 4-year freedom from maximal Grade 2+ late toxicity was 81% and 91% for GU and GI systems, respectively, and by last follow-up, the rates of Grade 2+ GU and GI toxicity were 9% and 5%, respectively. On multivariate analysis, whole-pelvic IMRT was associated with Grade 2+ GU toxicity and age was associated with Grade 2+ GI toxicity. Freedom from Grade 2+ GI toxicity at 4 years was 100% for men with rectal V 70 ≤10%, V 65 ≤20%, and V 40 ≤40%; 92% for men with rectal V 70 ≤20%, V 65 ≤40%, and V 40 ≤80%; and 85% for men exceeding these criteria (p = 0.13). These criteria were more highly associated with GI toxicity in men aged ≥70 years (p = 0.07). No bladder dose–volume relationships were associated with the risk of GU toxicity. Conclusions: IMRT is associated with low rates of severe GU or GI toxicity after treatment for prostate cancer. Rectal dose constraints may help limit late GI morbidity.

  18. Characteristics of manipulative in mathematics laboratory (United States)

    Istiandaru, A.; Istihapsari, V.; Prahmana, R. C. I.; Setyawan, F.; Hendroanto, A.


    A manipulative is a teaching aid designed such that students could understand mathematical concepts by manipulating it. This article aims to provide an insight to the characteristics of manipulatives produced in the mathematics laboratory of Universitas Ahmad Dahlan, Indonesia. A case study was conducted to observe the existing manipulatives produced during the latest three years and classified the manipulatives based on the characteristics found. There are four kinds of manipulatives: constructivism manipulative, virtual manipulative, informative manipulative, and game-based manipulative. Each kinds of manipulative has different characteristics and impact towards the mathematics learning.

  19. Toxicological Considerations, Toxicity Assessment, and Risk Management of Inhaled Nanoparticles. (United States)

    Bakand, Shahnaz; Hayes, Amanda


    Novel engineered nanoparticles (NPs), nanomaterial (NM) products and composites, are continually emerging worldwide. Many potential benefits are expected from their commercial applications; however, these benefits should always be balanced against risks. Potential toxic effects of NM exposure have been highlighted, but, as there is a lack of understanding about potential interactions of nanomaterials (NMs) with biological systems, these side effects are often ignored. NPs are able to translocate to the bloodstream, cross body membrane barriers effectively, and affect organs and tissues at cellular and molecular levels. NPs may pass the blood-brain barrier (BBB) and gain access to the brain. The interactions of NPs with biological milieu and resulted toxic effects are significantly associated with their small size distribution, large surface area to mass ratio (SA/MR), and surface characteristics. NMs are able to cross tissue and cell membranes, enter into cellular compartments, and cause cellular injury as well as toxicity. The extremely large SA/MR of NPs is also available to undergo reactions. An increased surface area of the identical chemical will increase surface reactivity, adsorption properties, and potential toxicity. This review explores biological pathways of NPs, their toxic potential, and underlying mechanisms responsible for such toxic effects. The necessity of toxicological risk assessment to human health should be emphasised as an integral part of NM design and manufacture.

  20. Toxicological Considerations, Toxicity Assessment, and Risk Management of Inhaled Nanoparticles

    Directory of Open Access Journals (Sweden)

    Shahnaz Bakand


    Full Text Available Novel engineered nanoparticles (NPs, nanomaterial (NM products and composites, are continually emerging worldwide. Many potential benefits are expected from their commercial applications; however, these benefits should always be balanced against risks. Potential toxic effects of NM exposure have been highlighted, but, as there is a lack of understanding about potential interactions of nanomaterials (NMs with biological systems, these side effects are often ignored. NPs are able to translocate to the bloodstream, cross body membrane barriers effectively, and affect organs and tissues at cellular and molecular levels. NPs may pass the blood–brain barrier (BBB and gain access to the brain. The interactions of NPs with biological milieu and resulted toxic effects are significantly associated with their small size distribution, large surface area to mass ratio (SA/MR, and surface characteristics. NMs are able to cross tissue and cell membranes, enter into cellular compartments, and cause cellular injury as well as toxicity. The extremely large SA/MR of NPs is also available to undergo reactions. An increased surface area of the identical chemical will increase surface reactivity, adsorption properties, and potential toxicity. This review explores biological pathways of NPs, their toxic potential, and underlying mechanisms responsible for such toxic effects. The necessity of toxicological risk assessment to human health should be emphasised as an integral part of NM design and manufacture.

  1. Testing of CFC replacement fluids for arc-induced toxic by-products

    Energy Technology Data Exchange (ETDEWEB)

    Cravey, W.R.; Goerz, D.A.; Hawley-Fedder, R.A.


    The authors have developed a unique test-stand for quantifying the generation of perfluoroisobutylene (PFIB) in chlorofluorocarbon (CFC) replacement fluids when they are subjected to high electrical stress/breakdown environments. PFIB is an extremely toxic gas with a threshold limit value of 10 ppbv as set by the American Conference of Governmental Industrial Hygienists. They have tested several new fluids from various manufacturers for their potential to generate PFIB. Their goal is to determine breakdown characteristics and quantify toxic by-products of these replacement fluids to determine a safe, usable alternative for present CFC`s.

  2. Characteristics of Independent Music Teachers (United States)

    Upitis, Rena; Abrami, Philip C.; Brook, Julia; Boese, Karen; King, Matthew


    The purpose of the present study was to learn about the characteristics of independent music teachers, their beliefs about music teaching, and their studio practices. A self-report survey included questions about the teachers' (a) background experiences, (b) pedagogical approaches, (c) use of digital technologies, and (d) professional development…

  3. Acute gastrointestinal and genitourinary toxicity of image-guided intensity modulated radiation therapy for prostate cancer using a daily water-filled endorectal balloon

    International Nuclear Information System (INIS)

    Deville, Curtiland; Both, Stefan; Bui, Viet; Hwang, Wei-Ting; Tan, Kay-See; Schaer, Mattia; Tochner, Zelig; Vapiwala, Neha


    Our purpose was to report acute gastrointestinal (GI) and genitourinary (GU) toxicity rates for prostate cancer patients undergoing image-guided intensity modulated radiation therapy (IG-IMRT) with a daily endorectal water-filled balloon (ERB H2O ), and assess associations with planning parameters and pretreatment clinical characteristics. The first 100 patients undergoing prostate and proximal seminal vesicle IG-IMRT with indexed-lumen 100 cc ERB H2O to 79.2 Gy in 1.8 Gy fractions at our institution from 12/2008- 12/2010 were assessed. Pretreatment characteristics, organ-at-risk dose volume histograms, and maximum GU and GI toxicities (CTCAE 3.0) were evaluated. Logistic regression models evaluated univariate association between toxicities and dosimetric parameters, and uni- and multivariate association between toxicities and pretreatment characteristics. Mean age was 68 (range 51–88). Thirty-two, 49, and 19 patients were low, intermediate, and high-risk, respectively; 40 received concurrent androgen deprivation. No grade 3 or greater toxicities were recorded. Maximum GI toxicity was grade 0, 1, and 2 in 69%, 23%, and 8%, respectively. Infield (defined as 1 cm above/below the CTV) rectal mean/median doses, D75, V30, and V40 and hemorrhoid history were associated with grade 2 GI toxicity (Ps < 0.05). Maximum acute GU toxicity was grade 0, 1, and 2 for 17%, 41%, and 42% of patients, respectively. Infield bladder V20 (P = 0.03) and pretreatment International Prostate Symptom Scale (IPSS) (P = 0.003) were associated with grade 2 GU toxicity. Prostate IG-IMRT using a daily ERB H2O shows low rates of acute GI toxicity compared to previous reports of air-filled ERB IMRT when using stringent infield rectum constraints and comparable GU toxicities

  4. Application of recombinant fluorescent mammalian cells as a toxicity biosensor. (United States)

    Kim, E J; Lee, Y; Lee, J E; Gu, M B


    With respect to developing a more sensitive biosensor, a recombinant fluorescent Chinese Hamster Ovary cell line was used for the monitoring of various toxicants. Both cell lines, EFC-500 and KFC-A10, were able to detect toxicants sensitively. They were characterized with mitomycin C and gamma-ray as genotoxicants and bisphenol A, nonylphenol, ziram and methyl bromide as possible and known EDCs. When compared to each other, the response of KFC-A10 was generally more informative and sensitive. Compared to typical bacterial biosensor systems, these cell lines offered a sensitivity of 2- to 50-fold greater for the tested chemicals. Based on these results, the use of mammalian cells offers a sensitive biosensor system that is not only fast, cheap and reproducible but also capable of monitoring the endocrine-like characteristics of environmental toxicants.

  5. Toxicity of Carbon Nanotubes and its Implications for Occupational and Environmental Health (United States)

    Lam, Chiu-wing; James, John T.


    This viewgraph document reviews the sources of Nano particles in the environment, the structure and properties of Carbon Nanotubes (CNTs), the physical characteristics of CNT materials, pulmonary and other health concerns of exposure to CNTs. The toxicity of CNT in rodents is summarized and some natural, and man-made sources of CNTs are shown. CNTs are electrically and thermally conductive, fibrous, biopersistent and very complicated in structures. The factors affecting toxicity of CNTs are more than size and surface area.

  6. Toxicity and elemental composition of particulate matter from outdoor and indoor air of elementary schools in Munich, Germany. (United States)

    Oeder, S; Dietrich, S; Weichenmeier, I; Schober, W; Pusch, G; Jörres, R A; Schierl, R; Nowak, D; Fromme, H; Behrendt, H; Buters, J T M


    Outdoor particulate matter (PM(10)) is associated with detrimental health effects. However, individual PM(10) exposure occurs mostly indoors. We therefore compared the toxic effects of classroom, outdoor, and residential PM(10). Indoor and outdoor PM(10) was collected from six schools in Munich during teaching hours and in six homes. Particles were analyzed by scanning electron microscopy and X-ray spectroscopy (EDX). Toxicity was evaluated in human primary keratinocytes, lung epithelial cells and after metabolic activation by several human cytochromes P450. We found that PM(10) concentrations during teaching hours were 5.6-times higher than outdoors (117 ± 48 μg/m(3) vs. 21 ± 15 μg/m(3), P particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%, probably originating from paper). Outdoor PM contained more Ca-sulfate particles (38%). Indoor PM at 6 μg/cm(2) (10 μg/ml) caused toxicity in keratinocytes and in cells expressing CYP2B6 and CYP3A4. Toxicity by CYP2B6 was abolished with the reactive oxygen species scavenger N-acetylcysteine. We concluded that outdoor PM(10) and indoor PM(10) from homes were devoid of toxicity. Indoor PM(10) was elevated, chemically different and toxicologically more active than outdoor PM(10). Whether the effects translate into a significant health risk needs to be determined. Until then, we suggest better ventilation as a sensible option. Indoor air PM(10) on an equal weight base is toxicologically more active than outdoor PM(10). In addition, indoor PM(10) concentrations are about six times higher than outdoor air. Thus, ventilation of classrooms with outdoor air will improve air quality and is likely to provide a health benefit. It is also easier than cleaning PM(10) from indoor air, which has proven to be tedious. © 2011 John Wiley & Sons A/S.

  7. Colour and toxic characteristics of metakaolinite-hematite pigment for integrally coloured concrete, prepared from iron oxide recovered from a water treatment plant of an abandoned coal mine (United States)

    Sadasivam, Sivachidambaram; Thomas, Hywel Rhys


    A metakaolinite-hematite (KH) red pigment was prepared using an ocherous iron oxide sludge recovered from a water treatment plant of an abandoned coal mine. The KH pigment was prepared by heating the kaolinite and the iron oxide sludge at kaolinite's dehydroxylation temperature. Both the raw sludge and the KH specimen were characterised for their colour properties and toxic characteristics. The KH specimen could serve as a pigment for integrally coloured concrete and offers a potential use for the large volumes of the iron oxide sludge collected from mine water treatment plants.

  8. Influences of the coating on silver nanoparticle toxicity in a chronic test with Daphnia magna

    DEFF Research Database (Denmark)

    Sakka, Y.; Mackevica, Aiga; Skjolding, Lars Michael


    coated AgNP in a chronic Daphnia test. One type of AgNP was coated with citrate (cAgNP), the other AgNP were generally uncoated (pAgNP; p= pure), but sterically stabilized by an organic dispersant. Particles with a similar shape and diameter were chosen. The focus of the study was to relate observed......Sources for differences in silver nanoparticle toxicity at standardized conditions can be numerous. They range from particle properties and their actual concentrations to differences in uptake or depuration by the test organisms. In the present study we compared the toxicity of two differently...... differences in toxicity to characteristics of the AgNP, like size or surface potential, or to their corresponding behaviour during the test, like dissolution or uptake. The characteristics and the behaviour of the AgNP were investigated for changes in stability and especially the release of silver ions...

  9. Discovering less toxic ionic liquids by using the Microtox® toxicity test. (United States)

    Hernández-Fernández, F J; Bayo, J; Pérez de los Ríos, A; Vicente, M A; Bernal, F J; Quesada-Medina, J


    New Microtox® toxicity data of 16 ionic liquids of different cationic and anionic composition were determined. The ionic liquids 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate, [BMPyr(+)][TFO(-)], 1-butyl-1-methylpyrrolidinium chloride, [BMPyr(+)][Cl(-)], hydroxypropylmethylimidazolium fluoroacetate, [HOPMIM(+)][FCH2COO(-)], and hydroxypropylmethylimidazolium glycolate [HOPMIM(+)][glycolate(-)] were found to be less toxic than conventional organic solvent such as chloroform or toluene, accoding the Microtox® toxicity assays. The toxicity of pyrrolidinium cation was lower than the imidazolium and pyridinium ones. It was found that the inclusion of an hydroxyl group in the alkyl chain length of the cation also reduce the toxicity of the ionic liquid. To sum up, the Microtox® toxicity assays can be used as screening tool to easily determined the toxicity of a wide range of ionic liquids and the toxicity data obtained could allow the obtention of structure-toxicity relationships to design less toxic ionic liquids. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. [Selecting methods and awaiting growth: the teaching experience of fundamental nursing practicum instructors]. (United States)

    Lin, Hui-Chen; Lin, Chi-Yi; Chien, Tsui-Wei; Liu, Kuei-Fen; Chen, Miao-Yen; Lin, Wen-Chuan


    A constellation of factors accounts for teaching efficacy in the fundamental nursing practicum. Teachers play a critical role in terms of designing and executing an appropriate teaching plan, choosing effective methods, and holding appropriate teaching attitudes. It is thus extremely important that clinical teachers master the core characteristics of basic nursing practice. This study aimed to illuminate the core characteristics of basic nursing practice for students for reference by clinical practicum teachers. Qualitative research was used to identify the fundamentals of nursing practice by clinical teacher. Five focus group meetings were convened during the practice period. The researchers presided over group discussions held during the normal weekly teaching schedule and lasting approximately 2-4 hours each. The content analysis was adopted to analyze the data. Three major themes were proposed, including (1) student status: "novices were stymied by problems and thus improved slowly"; (2) teacher awareness: "teachers need to be aware of student capabilities, mood, and discomfort"; and (3) teaching style: "a good choice of methods should support and encourage students. To cultivate professional nursing knowledge and self-confidence for future professional commitment, clinical teachers must first understand the characteristics and motivations of learning of their students and then select the, skills, and attitudes appropriate to provide step-by-step guidance. Communication with staffs and the preparation of atmosphere prior to nursing practice are also essential for students. Results provide insights into the technical college environment with regard to basic-level clinical nursing practice.

  11. Validation of a biotic ligand model on site-specific copper toxicity to Daphnia magna in the Yeongsan River, Korea. (United States)

    Park, Jinhee; Ra, Jin-Sung; Rho, Hojung; Cho, Jaeweon; Kim, Sang Don


    The objective of this study was to determine whether the water effect ratio (WER) or biotic ligand model (BLM) could be applied to efficiently develop water quality criteria (WQC) in Korea. Samples were collected from 12 specific sites along the Yeongsan River (YSR), Korea, including two sewage treatment plants and one estuary lake. A copper toxicity test using Daphnia magna was performed to determine the WER and to compare to the BLM prediction. The results of the WER from YSR samples also indicated significantly different copper toxicities in all sites. The model-based predictions showed that effluent and estuary waters had significantly different properties in regard to their ability to be used to investigate water characteristics and copper toxicity. It was supposed that the slight water characteristics changes, such as pH, DOC, hardness, conductivity, among others, influence copper toxicity, and these variable effects on copper toxicity interacted with the water composition. The 38% prediction was outside of the validation range by a factor of two in all sites, showing a poor predictive ability, especially in STPs and streams adjacent to the estuary, while the measured toxicity was more stable. The samples that ranged from pH 7.3-7.7 generated stable predictions, while other samples, including those with lower and the higher pH values, led to more unstable predictions. The results also showed that the toxicity of Cu in sample waters to D. magna was closely proportional to the amounts of acidity, including the carboxylic and phenolic groups, as well as the DOC concentrations. Consequently, the acceptable prediction of metal toxicity in various water samples needs the site-specific results considering the water characteristics such as pH and DOC properties particularly in STPs and estuary regions. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Resident training for eclampsia and magnesium toxicity management: simulation or traditional lecture? (United States)

    Fisher, Nelli; Bernstein, Peter S; Satin, Andrew; Pardanani, Setul; Heo, Hye; Merkatz, Irwin R; Goffman, Dena


    To compare eclampsia and magnesium toxicity management among residents randomly assigned to lecture or simulation-based education. Statified by year, residents (n = 38) were randomly assigned to 3 educational intervention groups: Simulation→Lecture, Simulation, and Lecture. Postintervention simulations were performed for all and scored using standardized lists. Maternal, fetal, eclampsia management, and magnesium toxcity scores were assigned. Mann-Whitney U, Wilcoxon rank sum and χ(2) tests were used for analysis. Postintervention maternal (16 and 15 vs 12; P < .05) and eclampsia (19 vs 16; P < .05) scores were significantly better in simulation based compared with lecture groups. Postintervention magnesium toxcitiy and fetal scores were not different among groups. Lecture added to simulation did not lead to incremental benefit when eclampsia scores were compared between Simulation→Lecture and Simulation (19 vs 19; P = nonsignificant). Simulation training is superior to traditional lecture alone for teaching crucial skills for the optimal management of both eclampsia and magnesium toxicity, 2 life-threatening obstetric emergencies. Published by Mosby, Inc.

  13. [Application of mind map in teaching of medical parasitology]. (United States)

    Zhou, Hong-Chang; Shao, Sheng-Wen; Xu, Bo-Ying


    To improve the teaching quality of medical parasitology, mind map, a simple and effective learning method, was introduced. The mind map of each chapter was drawn by teacher and distributed to students before the class. It was helpful for teacher to straighten out the teaching idea, and for students to grasp the important learning points, perfect the class notes and improve learning efficiency. The divergent characteristics of mind map can also help to develop the students' innovation ability.

  14. A Teaching Case of Subject Clause Based on Implicit Learning

    Institute of Scientific and Technical Information of China (English)



    The New English curriculum criteria suggest teaching English grammar based on the students’cognitive characteristics and emotional needs,helping them discover the rules and encouraging them to master the grammar by using it.But due to the limited time in a lesson,many English teachers adopt a simple approach to teach grammar,in which students are required to memorize the rules first and then practice a lot.This approach is effec-

  15. Residents' Engagement and Empathy Associated With Their Perception of Faculty's Teaching Performance

    NARCIS (Netherlands)

    Lases, S. S. Lenny; Arah, Onyebuchi A.; Pierik, E. G. J. M. Robert; Heineman, Erik; Lombarts, M. J. M. H. Kiki


    Faculty members rely on residents' feedback about their teaching performance. The influence of residents' characteristics on evaluations of faculty is relatively unexplored. We aimed to evaluate the levels of work engagement and empathy among residents and the association of both characteristics

  16. Residents' engagement and empathy associated with their perception of faculty's teaching performance

    NARCIS (Netherlands)

    Lases, S. S. Lenny; Arah, Onyebuchi A.; Pierik, E. G. J. M. Robert; Heineman, Erik; Lombarts, M. J. M. H. Kiki


    Faculty members rely on residents' feedback about their teaching performance. The influence of residents' characteristics on evaluations of faculty is relatively unexplored. We aimed to evaluate the levels of work engagement and empathy among residents and the association of both characteristics

  17. Communication aspect of contemporary teaching from the perspective of students and teachers in primary schools from a border municipality of Bosilegrad


    Jovanović, Marija; Stojnev, Mirjana; Kovčić, Vesna


    Contemporary teaching, nowadays, more than before, is significantly determined by the communication that happens during the teaching process. With its characteristics and development potential, communication affects the achievement of the objectives and tasks of educational work in the classroom and essentially determines its quality and efficiency. The specifics stemming from the immediate social context impose on communication in teaching certain characteristics that can, to a greater or le...

  18. Autophagy as a Possible Underlying Mechanism of Nanomaterial Toxicity

    Directory of Open Access Journals (Sweden)

    Vanessa Cohignac


    Full Text Available The rapid development of nanotechnologies is raising safety concerns because of the potential effects of engineered nanomaterials on human health, particularly at the respiratory level. Since the last decades, many in vivo studies have been interested in the pulmonary effects of different classes of nanomaterials. It has been shown that some of them can induce toxic effects, essentially depending on their physico-chemical characteristics, but other studies did not identify such effects. Inflammation and oxidative stress are currently the two main mechanisms described to explain the observed toxicity. However, the exact underlying mechanism(s still remain(s unknown and autophagy could represent an interesting candidate. Autophagy is a physiological process in which cytoplasmic components are digested via a lysosomal pathway. It has been shown that autophagy is involved in the pathogenesis and the progression of human diseases, and is able to modulate the oxidative stress and pro-inflammatory responses. A growing amount of literature suggests that a link between nanomaterial toxicity and autophagy impairment could exist. In this review, we will first summarize what is known about the respiratory effects of nanomaterials and we will then discuss the possible involvement of autophagy in this toxicity. This review should help understand why autophagy impairment could be taken as a promising candidate to fully understand nanomaterials toxicity.


    Directory of Open Access Journals (Sweden)

    Muhammad Jarir


    Full Text Available This paper examined the most important methods used in the teaching of Islamic fiqh at the university level. The paper identified two types of methods and highlighted their advantages and disadvantages. The study particularly highlighted the Islamic perception of the methods and the optimal characteristics of a fiqh instructor. The paper concluded with a number of suggestion and recommendation that’s my correct the course of university teaching of Islamic fiqh. The paper mainly calls for the need to diagnose the causes of students’ weaknesses in this field and to find solutions to these causes.Copyright © 2013 by Al-Ta'lim All right reservedDOI: 10.15548/jt.v20i2.36

  20. Anesthesiology residents’ perspective about good teaching – a qualitative needs assessment

    Directory of Open Access Journals (Sweden)

    Ortwein, Heiderose


    Full Text Available [english] Background: Germany, like many other countries, will soon have a shortage of qualified doctors. One reason for the dissatisfaction amongst medical residents are the relatively unstructured residency training programs despite increasing importance of outcome-based education. The aim of our study was to identify characteristics and requirements for good teaching during anesthesiology residency training from the resident’s point of view. Methods: A consensus workshop with residents from all medical universities in Germany was held. Participants were allocated to one of the three topics, chosen based on a 2009 nationwide evaluation of residency. The three topics were (A characteristics of helpful/good teachers, haracteristics of helpful/good conditions and (C characteristics of helpful/good curricular structure. Each group followed a nominal group technique consensus process to define and rank characteristics for a good residency.Results: 31 (79.5% resident representatives were present. The consented results put emphasis on the importance of structured curricula including transparent goals and objectives, in training formative assessments and quality assurance measures for the program. Residents further long for trained trainers with formal teaching qualifications and protected teaching time.Conclusions: Good residency training requires careful consideration of all stakeholders’ needs. Results reflect and extend previous findings and are at least to some degree easily implemented. These findings are an important step to establish a broader consensus within the discipline.

  1. Evaluation of Socio-Demographic Characteristics of HIV/AIDS ...

    African Journals Online (AJOL)

    Evaluation of Socio-Demographic Characteristics of HIV/AIDS Patients in a Tertiary Hospital. ... Journal of Pharmaceutical and Allied Sciences. Journal Home ... Keywords: Socio-demographics, HIV/AID, Retrospective, Teaching hospital ...

  2. Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors. (United States)

    Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene


    The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests. © 2015 SETAC.

  3. Computer Multimedia Assisted English Vocabulary Teaching Courseware

    Directory of Open Access Journals (Sweden)

    Nan Yue


    Full Text Available English vocabulary is often regarded as the most boring link in English learning. However, English vocabulary is the basis of all aspects of English learning. Therefore, enriching the process of English vocabulary learning and stimulating the interest of English vocabulary learning are the keys to the reform of English vocabulary teaching. The computer multimedia is developing and popularizing rapidly with the rapid development of informationization and networking, which plays its role in more and more fields. The application of multimedia technology in the field of teaching is no longer strange. This paper mainly studied the design of computer multimedia assisted English vocabulary teaching courseware. First of all, this paper gave an overview of computer multimedia technology from the aspects of concept, characteristics, development and application situation, which cited and analyzed the cognitive learning theory and memory law. Under the guidance of scientific laws and in combination with the requirement analysis and pattern construction of English vocabulary teaching, this paper realized the module design, style design and database design of English vocabulary courseware. Finally, the content of English vocabulary teaching courseware was demonstrated, and its application effect was verified through the combination of subjective evaluation and objective evaluation. This article has an important guiding significance for stimulating students’ interest in English vocabulary learning and enhancing the quality of vocabulary teaching.

  4. Relationship between physico-chemical characteristics and potential toxicity of PM10. (United States)

    Megido, Laura; Suárez-Peña, Beatriz; Negral, Luis; Castrillón, Leonor; Suárez, Susana; Fernández-Nava, Yolanda; Marañón, Elena


    PM10 was sampled at a suburban location affected by traffic and industry in the north of Spain. The samples were analysed to determine the chemical components of PM10 (organic and elemental carbon, soluble chemical species and metals). The aim of this study was to assess the toxicity of PM10 in terms of the bulk analysis and the physico-chemical properties of the particles. Total carbon, sulphates, ammonium, chlorides and nitrates were found to be the major constituents of PM10. The contribution of the last of these was found to increase significantly with PM10 concentration (Pearson coefficient correlation of 0.7, p-value major risk to human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Learning to teach effectively: Science, technology, engineering, and mathematics graduate teaching assistants' teaching self-efficacy (United States)

    Dechenne, Sue Ellen

    Graduate teaching assistants (GTAs) from science, technology, engineering, and mathematics (STEM) are important in the teaching of undergraduate students (Golde & Dore, 2001). However, they are often poorly prepared for teaching (Luft, Kurdziel, Roehrig, & Turner, 2004). This dissertation addresses teaching effectiveness in three related manuscripts: (1) A position paper that summarizes the current research on and develops a model of GTA teaching effectiveness. (2) An adaptation and validation of two instruments; GTA perception of teaching training and STEM GTA teaching self-efficacy. (3) A model test of factors that predict STEM GTA teaching self-efficacy. Together these three papers address key questions in the understanding of teaching effectiveness in STEM GTAs including: (a) What is our current knowledge of factors that affect the teaching effectiveness of GTAs? (b) Given that teaching self-efficacy is strongly linked to teaching performance, how can we measure STEM GTAs teaching self-efficacy? (c) Is there a better way to measure GTA teaching training than currently exists? (d) What factors predict STEM GTA teaching self-efficacy? An original model for GTA teaching effectiveness was developed from a thorough search of the GTA teaching literature. The two instruments---perception of training and teaching self-efficacy---were tested through self-report surveys using STEM GTAs from six different universities including Oregon State University (OSU). The data was analyzed using exploratory and confirmatory factor analysis. Using GTAs from the OSU colleges of science and engineering, the model of sources of STEM GTA teaching self-efficacy was tested by administering self-report surveys and analyzed by using OLS regression analysis. Language and cultural proficiency, departmental teaching climate, teaching self-efficacy, GTA training, and teaching experience affect GTA teaching effectiveness. GTA teaching self-efficacy is a second-order factor combined from self

  6. Toxicity of nickel-spiked freshwater sediments to benthic invertebrates-Spiking methodology, species sensitivity, and nickel bioavailability (United States)

    Besser, John M.; Brumbaugh, William G.; Kemble, Nile E.; Ivey, Chris D.; Kunz, James L.; Ingersoll, Christopher G.; Rudel, David


    This report summarizes data from studies of the toxicity and bioavailability of nickel in nickel-spiked freshwater sediments. The goal of these studies was to generate toxicity and chemistry data to support development of broadly applicable sediment quality guidelines for nickel. The studies were conducted as three tasks, which are presented here as three chapters: Task 1, Development of methods for preparation and toxicity testing of nickel-spiked freshwater sediments; Task 2, Sensitivity of benthic invertebrates to toxicity of nickel-spiked freshwater sediments; and Task 3, Effect of sediment characteristics on nickel bioavailability. Appendices with additional methodological details and raw chemistry and toxicity data for the three tasks are available online at

  7. Crossing Thresholds: Identifying conceptual transitions in postsecondary teaching

    Directory of Open Access Journals (Sweden)

    Susan Wilcox


    Full Text Available In this paper we report on research we conducted to begin the process of identifying threshold concepts in the field of postsecondary teaching. Meyer & Land (2006 propose that within all disciplinary fields there seem to be particular threshold concepts that serve as gateways, opening up new and previously inaccessible ways of thinking and practicing. We developed a series of questions focusing on the “troublesome” and “transformative” characteristics of threshold concepts and asked these questions of several constituent groups, including those who are new to practice and the body of knowledge in postsecondary teaching and those who are already knowledgeable and/or experienced in the field. Based on our interpretation of participants’ responses, we identified four recognized concepts in the field of postsecondary teaching as potential threshold concepts in this field: Assessment for/as learning; Learning-centred teaching; Accommodation for diversity; and, Context-driven practice. Our findings suggest that threshold concepts are relevant to the field of postsecondary teaching. Through this work, we hope to help educational developers and faculty members consider what is involved in learning to teach and developing teaching expertise, and to encourage critical discussion about the teaching development “curriculum” in postsecondary settings. Threshold concepts arise as a field develops and are defined as practitioners and scholars in the field define their field. At this stage, we believe the real value of threshold concepts for postsecondary teaching lies in the discussion that arises in the process of identifying and naming the concepts.

  8. Chemistry teaching in different social contexts

    Directory of Open Access Journals (Sweden)

    Bruno Ferreira dos Santos


    Full Text Available This article presents the development of a research program on the teaching of chemistry guided by a theoretical framework of the Sociology of Education, and discusses its main results. Under a comparative analysis perspective, the pedagogical practices of teachers of chemistry teachers who teach in schools of different social contexts were been characterized by a set of indicators related to the rules of pedagogical discourse and were associated to the macrossocial issues of power and control, according to the theory by Basil Bernstein. The article presents the most relevant results obtained, highlighting the characteristics less favorable to the acquisition of scientific knowledge and skills, and which often constitute the practices observed in the schools where study the most needy students of the social spectrum. On the other hand, some results also show that, by altering some of these characteristics, teachers can increase student’s performance. These results have implications for the education of chemistry teachers and for public policies. The final part discusses the further unfolding and new directions for future research related to this program.

  9. Resuspension of toxic aerosol using MATHEW--ADPIC wind field--transport and diffusion codes

    International Nuclear Information System (INIS)

    Porch, W.M.


    Computer codes have been written which estimate toxic aerosol resuspension based on computed deposition from a primary source, wind, and surface characteristics. The primary deposition pattern and the transport, diffusion, and redeposition of the resuspended toxic aerosol are calculated using a mass-consistent wind field model including topography (MATHEW) and a particle-in-cell diffusion and transport model (ADPIC) which were developed at LLL. The source term for resuspended toxic aerosol is determined by multiplying the total aerosol flux as a function of wind speed by the area of highest concentration and the fraction of suspended material estimated to be toxic. Preliminary calculations based on a test problem at the Nevada Test Site determined an hourly averaged maximum resuspension factor of 10 -4 for a 15 m/sec wind which is within an admittedly large range of resuspension factor measurements using experimental data

  10. Japanese Martial Arts as Popular Culture: Teaching Opportunity and Challenge

    Directory of Open Access Journals (Sweden)

    Stephen Robert NAGY


    Full Text Available Japanese martial arts, here after Japanese budō, are popular cultural icons that are found in films, comics, video games and books. Teaching Japanese budō at university offers a novel way to teach about East Asian and in particular Japanese culture, history, and philosophy while including ideas about the globalization and the localization of culture. Question though remains as to how and what should we teach about the popular culture of Japanese budō at the university level? This paper found that a comprehensive approach to teaching about budō was effective. By using many kinds of materials and the incorporation of opportunities to experience budō and to try budō, students were better able to grasp the historical, cultural and religious characteristics of budō.

  11. Determining the bioavailability and toxicity of lead contamination to earthworms requires using a combination of physicochemical and biological methods

    International Nuclear Information System (INIS)

    Luo, Wei; Verweij, Rudo A.; Gestel, Cornelis A.M. van


    This study aimed at assessing the bioavailability and toxicity of lead to Eisenia andrei in shooting range soils representing different land uses (forest, grassland, bullet plot). Soils contained 47–2398 mg Pb/kg dry weight (dw), but also had different pH-CaCl 2 (3.2–6.8) and organic matter contents (3.8–13%). Therefore artificial soils with different pH and organic matter contents and two natural soils were included as control soils. Earthworms were exposed for 28 days and toxicity and uptake of Pb were related to total, water and 0.01 M CaCl 2 extractable and porewater Pb concentrations as well as to soil characteristics. Pb uptake in the earthworms linearly increased with increasing soil concentrations. At >2000 mg Pb/kg dw and pH 3.3–3.5, high earthworm mortality with significant weight loss and complete inhibition of reproduction were recorded. At <1000 mg/kg dw, earthworm reproduction was more related to differences in pH and other soil characteristics than to Pb. -- Highlights: • Availability and earthworm toxicity of Pb determined in field-contaminated soils. • Earthworm toxicity of most-polluted soils explained from available Pb levels. • Earthworm response in less polluted soils mainly determined by soil pH. • Earthworm toxicity correlated with Pb uptake from the soil. • Soil properties explained differences in earthworm Pb uptake and effects. -- Combination of physicochemical and biological assays helped explaining Pb toxicity in shooting range soils from available Pb concentrations and soil characteristics

  12. A review of teaching skills development programmes for medical students. (United States)

    Marton, Gregory E; McCullough, Brendan; Ramnanan, Christopher J


    The CanMEDS role of Scholar requires that medical trainees develop their skills as medical educators. The development of teaching skills in undergraduate medical students is therefore desirable, especially in view of the teaching obligations in residency programmes. The goal of this review was to identify the characteristics and outcomes of programmes designed to develop the teaching skills of undergraduate medical students. The authors searched medical literature databases using combinations of the search terms 'medical student', 'teacher', 'teaching skills', 'peer teaching', 'near-peer teaching' and 'student as teacher'. Twenty papers fit the predetermined search criteria, which included original characterisations of specific programmes involving undergraduate medical students. Three types of initiative were identified in the reviewed articles: peer teaching programmes; teaching workshops, and community outreach programmes. The majority of study participants were students in Years 3 and 4. Subjective self-evaluation by participants using Likert scale-based surveys was by far the most commonly used method of measuring project outcomes. Objective, quantitative teaching-related outcomes were rarely noted in the reports reviewed. Self-perceived improvements in teaching skills were noted by participants in most of the reports. Other perceived benefits included increases in organisational skills, knowledge and confidence in giving feedback. Although several types of programmes have been shown to subjectively improve the teaching skills of undergraduate medical students, characterisation of the objective outcomes of these initiatives is lacking and requires further study. © 2015 John Wiley & Sons Ltd.

  13. Teacher Identity in Language Teaching: Integrating Personal, Contextual, and Professional Factors (United States)

    Pennington, Martha C.; Richards, Jack C.


    This article reviews notions of identity and teacher identity, how these relate to the specific characteristics of language teaching, and how teacher identity can evolve or be developed through experience and teacher education. The notion of teacher identity highlights the individual characteristics of the teacher and how these are integrated with…

  14. Antimony Toxicity

    Directory of Open Access Journals (Sweden)

    Shyam Sundar


    Full Text Available Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans. Improvements in working conditions have remarkably decreased the incidence of antimony toxicity in the workplace. As a therapeutic, antimony has been mostly used for the treatment of leishmaniasis and schistosomiasis. The major toxic side-effects of antimonials as a result of therapy are cardiotoxicity (~9% of patients and pancreatitis, which is seen commonly in HIV and visceral leishmaniasis co-infections. Quality control of each batch of drugs produced and regular monitoring for toxicity is required when antimonials are used therapeutically.

  15. Identifying inequitable exposure to toxic air pollution in racialized and low-income neighbourhoods to support pollution prevention

    Directory of Open Access Journals (Sweden)

    Suzanne Kershaw


    Full Text Available Numerous environmental justice studies have confirmed a relationship between population characteristics such as low-income or minority status and the location of environmental health hazards. However, studies of the health risks from exposure to harmful substances often do not consider their toxicological characteristics. We used two different methods, the unit-hazard and the distance-based approach, to evaluate demographic and socio-economic characteristics of the population residing near industrial facilities in the City of Toronto, Canada. In addition to the mass of air emissions obtained from the national pollutant release inventory (NPRI, we also considered their toxicity using toxic equivalency potential (TEP scores. Results from the unit-hazard approach indicate no significant difference in the proportion of low-income individuals living in host versus non-host census tracts (t(107 = 0.3, P = 0.735. However, using the distance-based approach, the proportion of low-income individuals was significantly higher (+5.1%, t(522 = 6.0, P <0.001 in host tracts, while the indicator for “racialized” communities (“visible minority” was 16.1% greater (t(521 = 7.2, P <0.001 within 2 km of a NPRI facility. When the most toxic facilities by non-carcinogenic TEP score were selected, the rate of visible minorities living near the most toxic NPRI facilities was significantly higher (+12.9%, t(352 = 3.5, P = 0.001 than near all other NPRI facilities. TEP scores were also used to identify areas in Toronto that face a double burden of poverty and air toxics exposure in order to prioritise pollution prevention.

  16. Section 10: Ground Water - Waste Characteristics & Targets (United States)

    HRS Training. The waste characteristics factor category in the ground water pathway is made up of two components: the toxicity/mobility of the most hazardous substance associated with the site and the hazardous waste quantity at the site.

  17. Differential toxicity and influence of salinity on acute toxicity of ...

    African Journals Online (AJOL)

    Differential toxicity and influence of salinity on acute toxicity of copper sulphate and lead nitrate against Oreochromis niloticus. KA Bawa-Allah, F Osuala, J Effiong. Abstract. This study investigated the salinity-tolerance of Oreochromis niloticus and the influence of salinity changes on the acute toxicities of copper sulphate ...

  18. Electrospray Ionization Mass Spectrometry: From Cluster Ions to Toxic metal Ions in Biology

    Energy Technology Data Exchange (ETDEWEB)

    Lentz, Nicholas B. [Iowa State Univ., Ames, IA (United States)


    This dissertation focused on using electrospray ionization mass spectrometry to study cluster ions and toxic metal ions in biology. In Chapter 2, it was shown that primary, secondary and quarternary amines exhibit different clustering characteristics under identical instrument conditions. Carbon chain length also played a role in cluster ion formation. In Chapters 3 and 4, the effects of solvent types/ratios and various instrumental parameters on cluster ion formation were examined. It was found that instrument interface design also plays a critical role in the cluster ion distribution seen in the mass spectrum. In Chapter 5, ESI-MS was used to investigate toxic metal binding to the [Gln11]-amyloid β-protein fragment (1-16). Pb and Cd bound stronger than Zn, even in the presence of excess Zn. Hg bound weaker than Zn. There are endless options for future work on cluster ions. Any molecule that is poorly ionized in positive ion mode can potentially show an increase in ionization efficiency if an appropriate anion is used to produce a net negative charge. It is possible that drug protein or drug/DNA complexes can also be stabilized by adding counter-ions. This would preserve the solution characteristics of the complex in the gas phase. Once in the gas phase, CID could determine the drug binding location on the biomolecule. There are many research projects regarding toxic metals in biology that have yet to be investigated or even discovered. This is an area of research with an almost endless future because of the changing dynamics of biological systems. What is deemed safe today may show toxic effects in the future. Evolutionary changes in protein structures may render them more susceptible to toxic metal binding. As the understanding of toxicity evolves, so does the demand for new toxic metal research. New instrumentation designs and software make it possible to perform research that could not be done in the past. What was undetectable yesterday will

  19. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC50 values of other test models

    International Nuclear Information System (INIS)

    Khangarot, B.S.; Das, Sangita


    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC 50 ) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC 50 values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r 2 ) for 17 physicochemical properties of metals or metal ions and EC 50 s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK sp ), softness parameter and some other physicochemical characteristics were significantly correlated with EC 50 s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC 50 s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  20. Acute Toxicity of Opuntia Ficus Indica and Pistacia Lentiscus Seed Oils in Mice


    Boukeloua, A; Belkhiri, A; Djerrou, Z; Bahri, L; Boulebda, N; Pacha, Y Hamdi


    Opuntia ficus indica and Pistacia lentiscus L. seeds are used in traditional medicine. The objective of this study was to investigate the toxicity of the fixed oil of Opuntia ficus indica and Pistacia lentiscus L. seeds in mice through determination of LD50 values, and also the physicochemical characteristics of the fixed oil of these oils. The acute toxicity of their fixed oil were also investigated in mice using the method of Kabba and Berhens. The fixed oil of Pistacia lentiscus and Opunti...

  1. Classification of baseline toxicants for QSAR predictions to replace fish acute toxicity studies. (United States)

    Nendza, Monika; Müller, Martin; Wenzel, Andrea


    Fish acute toxicity studies are required for environmental hazard and risk assessment of chemicals by national and international legislations such as REACH, the regulations of plant protection products and biocidal products, or the GHS (globally harmonised system) for classification and labelling of chemicals. Alternative methods like QSARs (quantitative structure-activity relationships) can replace many ecotoxicity tests. However, complete substitution of in vivo animal tests by in silico methods may not be realistic. For the so-called baseline toxicants, it is possible to predict the fish acute toxicity with sufficient accuracy from log K ow and, hence, valid QSARs can replace in vivo testing. In contrast, excess toxicants and chemicals not reliably classified as baseline toxicants require further in silico, in vitro or in vivo assessments. Thus, the critical task is to discriminate between baseline and excess toxicants. For fish acute toxicity, we derived a scheme based on structural alerts and physicochemical property thresholds to classify chemicals as either baseline toxicants (=predictable by QSARs) or as potential excess toxicants (=not predictable by baseline QSARs). The step-wise approach identifies baseline toxicants (true negatives) in a precautionary way to avoid false negative predictions. Therefore, a certain fraction of false positives can be tolerated, i.e. baseline toxicants without specific effects that may be tested instead of predicted. Application of the classification scheme to a new heterogeneous dataset for diverse fish species results in 40% baseline toxicants, 24% excess toxicants and 36% compounds not classified. Thus, we can conclude that replacing about half of the fish acute toxicity tests by QSAR predictions is realistic to be achieved in the short-term. The long-term goals are classification criteria also for further groups of toxicants and to replace as many in vivo fish acute toxicity tests as possible with valid QSAR

  2. Teaching Chemical Engineers about Teaching (United States)

    Heath, Daniel E.; Hoy, Mary; Rathman, James F.; Rohdieck, Stephanie


    The Chemical and Biomolecular Engineering Department at The Ohio State University in collaboration with the University Center for the Advancement of Teaching developed the Chemical Engineering Mentored Teaching Experience. The Mentored Teaching Experience is an elective for Ph.D. students interested in pursuing faculty careers. Participants are…

  3. Antibacterial properties and toxicity from metallic nanomaterials

    Directory of Open Access Journals (Sweden)

    Vimbela GV


    Full Text Available Gina V Vimbela,1,* Sang M Ngo,2,* Carolyn Fraze,3 Lei Yang,4,5 David A Stout5–7 1Department of Chemical Engineering, 2Department of Electrical Engineering, California State University, Long Beach, CA, 3Brigham Young University Idaho, Rexburg, ID, USA; 4Department of Orthopaedics, Orthopaedic Institute, The First Affiliated Hospital, 5International Research Center for Translational Orthopaedics (IRCTO, Soochow University, Suzhou, Jiangsu, People’s Republic of China; 6Department of Mechanical and Aerospace Engineering, 7Department of Biomedical Engineering, California State University, Long Beach, CA, USA *These authors contributed equally to this work Abstract: The era of antibiotic resistance is a cause of increasing concern as bacteria continue to develop adaptive countermeasures against current antibiotics at an alarming rate. In recent years, studies have reported nanoparticles as a promising alternative to antibacterial reagents because of their exhibited antibacterial activity in several biomedical applications, including drug and gene delivery, tissue engineering, and imaging. Moreover, nanomaterial research has led to reports of a possible relationship between the morphological characteristics of a nanomaterial and the magnitude of its delivered toxicity. However, conventional synthesis of nanoparticles requires harsh chemicals and costly energy consumption. Additionally, the exact relationship between toxicity and morphology of nanomaterials has not been well established. Here, we review the recent advancements in synthesis techniques for silver, gold, copper, titanium, zinc oxide, and magnesium oxide nanomaterials and composites, with a focus on the toxicity exhibited by nanomaterials of multidimensions. This article highlights the benefits of selecting each material or metal-based composite for certain applications while also addressing possible setbacks and the toxic effects of the nanomaterials on the environment. Keywords

  4. Teaching Culture in the EFL/ESL Classroom (United States)

    Tran, Thu Hoang


    This article is intended to discuss prominent issues in teaching culture to second and foreign language students. The concepts of language and culture will be defined, respectively. Next, the characteristics and components of culture will be presented. In addition, commonly used terms in language and culture including enculturation, acculturation,…

  5. Personality Factors in the Student Teaching Triad. (United States)

    Hughes, Robert, Jr.; And Others

    A match or mis-match of cooperating teachers and student teachers on personality characteristics may have an important role in the overall effectiveness of the student teaching experience. Among the different personality factors that may affect participant relationships are flexibility, empathy, and self-esteem. To assess the validity of measures…

  6. Toxic stress and protective factors in multi-ethnic school age children: A research protocol. (United States)

    Condon, Eileen M; Sadler, Lois S; Mayes, Linda C


    Exposure to stressful environments in early childhood can cause a toxic stress response and lead to poor health outcomes, including obesity, cardiac disease, diabetes, and mental illness. In animals and maltreated children, the presence of a nurturing caregiver can buffer against the physiological disruptions associated with a toxic stress response; however, the specific caregiver and parenting characteristics that best promote a protective relationship in humans remain largely unexplored, particularly in families living in high-risk environments. In this study, framed in an ecobiodevelopmental (EBD) model, a cross-sectional design is being used to study 54 multi-ethnic, urban maternal-child dyads with children at early school age (4-9 years). Mothers' past experiences, mental health, and caregiving patterns and children's hair cortisol, C-reactive protein, pro-inflammatory cytokines, blood pressure, BMI, behavior, and school performance are being analyzed to identify maternal characteristics that may protect against children's toxic stress response in families at high risk for exposure to stressors such as poverty, trauma, or exposure to violence. © 2018 Wiley Periodicals, Inc.

  7. Teaching Diversity

    Directory of Open Access Journals (Sweden)

    Kay Young McChesney


    Full Text Available This article is targeted to faculty teaching race and ethnicity, racism, diversity, and multicultural courses. Many students equate race with skin color. The premise of this article is that to teach students about the social construction of race, teachers must first know enough science to teach students that race is not biological. This article examines the biology of race by showing how advances in DNA sequencing led to genetics research that supports arguments that race is not biological. DNA comparisons show that all human populations living today are one species that came from Africa. The article explains the migration of humans out of Africa about 60,000 years ago and how they populated Australia, then Asia, Europe, and the Americas. The article shows how recent research maps the timing of the migration and admixture of specific population groups into Europe and India. The article shows how a mutation in one nucleotide can result in a trait like blue eyes, or Hemoglobin S (which confers resistance to malaria, which can be subject to evolution through natural selection. DNA comparisons show how natural selection shaped the genetics of human skin color to adapt to less UV light in the northern latitudes of Europe and Asia. The article shows that there is no relation between skin color or other “racial” characteristics and complex traits like intelligence. The science in this article will help teachers explain that as race is not biological, race is socially constructed and culturally enacted.

  8. Evaluation of iodate toxicity (KIO3 on growth, morpho-physiological characteristics and mineral nutrients concentrations of potato (Solanum tuberosum L. cv. Agria

    Directory of Open Access Journals (Sweden)

    Ezatollah Esfandiari


    Full Text Available The current study was aimed to assess the effects of different iodate concentrations on morpho-physiological characteristics of potato. In this regard, a pot experiment was carried out during the spring and summer 2013. Five concentrations of KIO3 including control beside 10, 20, 40, and 80 mg/Kgsoil were applied through irrigation system. The results showed that all selected agronomical and morphological characteristics of potato except dry weight of stem (SDW and root (RDW were negatively affected by high iodate concentrations. The results showed that applying 80 mg KIO3/Kgsoil compared to control resulted in around 15, 86, 84, 41, 16, 25, 20, and 87% reductions in harvest index (HI, leaf dry weight (LDW, tuber dry weight (TDW, plant dry weight (PDW, stem length (SL, root length (RL, plant height (PH, and number of tuber per plant (NT, respectively. Iodate application (80 mg KIO3/Kgsoil vs. control also affected potato’s physiological characteristics including chlorophyll content (SPAD, relative water content (RWC, water use efficiency (WUE, evapo-transpiration efficiency (ETE, cell membrane stability index (CMSI and tolerance index (TI showing around 27, 12, 87, 39, 40, and 77% reductions for each one, respectively. Increasing iodate concentrations, although, showed no effect of Zn concentration of root and Fe and Mn concentrations of leaf, gradually decreased Zn concentration of leaf and increased Fe and Mn concentrations of root and Cu concentrations of root and leaf. Plants also showed several visible symptoms including stunting, chlorosis, browning of leaf tip and reduction in growth due to iodate toxicity.

  9. Evaluation on the toxicity of nanoAg to bovine serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Liu Rutao, E-mail: [School of Environmental Science and Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Sun Feng; Zhang Lijun; Zong Wansong; Zhao Xingchen; Wang Li; Wu Ruolin [School of Environmental Science and Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Hao Xiaopeng [State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100 (China)


    Measuring protein damage by nanomaterials may give insight into the mechanisms of toxicity of nanomaterials. The toxic effects of nanoAg on bovine serum albumin (BSA) were thoroughly studied using fluorescence spectroscopy, ultraviolet-visible absorption spectroscopy, resonance light scattering spectroscopy (RLS), circular dichroism spectroscopy (CD) and transmission electron microscopy (TEM). NanoAg had obvious toxic effects on BSA: nanoAg could increase the amount of helix and decrease the beta sheet structure, leading to a loosening of the protein skeleton. In the loose structure, internal hydrophobic amino acids are exposed and the characteristic fluorescence of BSA is obviously quenched. When the ratio of nanoAg and BSA increased to 1: 96 (wt/wt), the impact of nanoAg on the spectral properties leveled off. The RLS spectrum, TEM, CD spectra and electrophoresis results showed that BSA had destroyed the double-layer structure of nanoAg and covered its surface, generating a BSA-nanoAg complex held together by van der Waals and electrostatic forces. This paper provides a new perspective and method for determining the toxic effects of nanoAg on biological macromolecules.

  10. Highly qualified does not equal high quality: A study of urban stakeholders' perceptions of quality in science teaching (United States)

    Miranda, Rommel Joseph

    By employing qualitative methods, this study sought to determine the perceptions that urban stakeholders hold about what characteristics should distinguish a high school science teacher whom they would consider to demonstrate high quality in science teaching. A maximum variation sample of six science teachers, three school administrators, six parents and six students from a large urban public school district were interviewed using semi-structured, in-depth interview techniques. From these data, a list of observable characteristics which urban stakeholders hold as evidence of high quality in science teaching was generated. Observational techniques were utilized to determine the extent to which six urban high school science teachers, who meet the NCLB Act criteria for being "highly qualified", actually possessed the characteristics which these stakeholders hold as evidence of high quality in science teaching. Constant comparative analysis was used to analyze the data set. The findings suggest that urban stakeholders perceive that a high school science teacher who demonstrates high quality in science teaching should be knowledgeable about their subject matter, their student population, and should be resourceful; should possess an academic background in science and professional experience in science teaching; should exhibit professionalism, a passion for science and teaching, and a dedication to teaching and student learning; should be skillful in planning and preparing science lessons and in organizing the classroom, in presenting the subject matter to students, in conducting a variety of hands-on activities, and in managing a classroom; and should assess whether students complete class goals and objectives, and provide feedback about grades for students promptly. The findings further reveal that some of the urban high school science teachers who were deemed to be "highly qualified", as defined by the NCLB Act, engaged in practices that threatened quality in science

  11. Identification of Toxic Pyrrolizidine Alkaloids and Their Common Hepatotoxicity Mechanism

    Directory of Open Access Journals (Sweden)

    Xinmiao Yan


    Full Text Available Pyrrolizidine Alkaloids (PAs are currently one of the most important botanical hepatotoxic ingredients. Glutathion (GSH metabolism is the most reported pathway involved in hepatotoxicity mechanism of PAs. We speculate that, for different PAs, there should be a common mechanism underlying their hepatotoxicity in GSH metabolism. Computational methods were adopted to test our hypothesis in consideration of the limitations of current experimental approaches. Firstly, the potential targets of 22 PAs (from three major PA types in GSH metabolism were identified by reverse docking; Secondly, glutathione S-transferase A1 (GSTA1 and glutathione peroxidase 1 (GPX1 targets pattern was found to be a special characteristic of toxic PAs with stepwise multiple linear regressions; Furthermore, the molecular mechanism underlying the interactions within toxic PAs and these two targets was demonstrated with the ligand-protein interaction analysis; Finally, GSTA1 and GPX1 were proved to be significant nodes in GSH metabolism. Overall, toxic PAs could be identified by GSTA1 and GPX1 targets pattern, which suggests their common hepatotoxicity mechanism: the interfering of detoxication in GSH metabolism. In addition, all the strategies developed here could be extended to studies on toxicity mechanism of other toxins.

  12. Identification of Toxic Pyrrolizidine Alkaloids and Their Common Hepatotoxicity Mechanism. (United States)

    Yan, Xinmiao; Kang, Hong; Feng, Jun; Yang, Yiyan; Tang, Kailin; Zhu, Ruixin; Yang, Li; Wang, Zhengtao; Cao, Zhiwei


    Pyrrolizidine Alkaloids (PAs) are currently one of the most important botanical hepatotoxic ingredients. Glutathion (GSH) metabolism is the most reported pathway involved in hepatotoxicity mechanism of PAs. We speculate that, for different PAs, there should be a common mechanism underlying their hepatotoxicity in GSH metabolism. Computational methods were adopted to test our hypothesis in consideration of the limitations of current experimental approaches. Firstly, the potential targets of 22 PAs (from three major PA types) in GSH metabolism were identified by reverse docking; Secondly, glutathione S-transferase A1 (GSTA1) and glutathione peroxidase 1 (GPX1) targets pattern was found to be a special characteristic of toxic PAs with stepwise multiple linear regressions; Furthermore, the molecular mechanism underlying the interactions within toxic PAs and these two targets was demonstrated with the ligand-protein interaction analysis; Finally, GSTA1 and GPX1 were proved to be significant nodes in GSH metabolism. Overall, toxic PAs could be identified by GSTA1 and GPX1 targets pattern, which suggests their common hepatotoxicity mechanism: the interfering of detoxication in GSH metabolism. In addition, all the strategies developed here could be extended to studies on toxicity mechanism of other toxins.

  13. Linking the Organizational Forms Teachers and Teaching Methods in a Class Instructional Methodology

    Directory of Open Access Journals (Sweden)

    Graciela Nápoles-Quiñones


    Full Text Available A descriptive study was conducted to show the link between the organizational forms teachers and teaching methods, to expose the pedagogical theory, to deepen the teaching-learning process through methodological class. The main content of the work of teachers is the preparation and level rise; which requires the selection and use of working methods, ways and procedures in accordance with the real and objective conditions of staff who have received the action and conducive to teaching work. Teachers should be aware that you need to master the content they teach, be aware of the level of development of its students, the specific characteristics of the group and of each student, and competent to reciprocate the content they teach with reality.

  14. Teaching Morally and Teaching Morality (United States)

    Fenstermacher, Gary D.; Osguthorpe, Richard D.; Sanger, Matthew N.


    In this article, the authors introduce what they believe is an important distinction between teaching morality and teaching morally. In P-12 schools, the moral education debate often focuses on character education programs or other moral curricula. Such programs and curricula are championed as a means of teaching morality and transmitting moral…

  15. Teachers' conceptions of learning and teaching in student-centred medical curricula: the impact of context and personal characteristics

    NARCIS (Netherlands)

    Jacobs, J.C.G.; Luijk, S.J. van; Vleuten, C.P.M. van der; Kusurkar, R.A.; Croiset, G.; Scheele, F.


    BACKGROUND: Gibbs and Coffey (2004) have reported that teaching practices are influenced by teachers' conceptions of learning and teaching. In our previous research we found significant differences between teachers' conceptions in two medical schools with student-centred education. Medical school

  16. Gaseous emissions and toxic hazards associated with plastics in fire situations: A literature review (United States)

    Junod, T. L.


    The hazards of plastics in fire situations, the gases emitted, the factors influencing the nature of these emissions, the characteristics of toxic gases, and the results of laboratory studies, are discussed. The literature pertaining to the pyrolysis and oxidation of plastics was reviewed. An effort was made to define the state of the art for determining the toxic gases emitted by plastics under fire conditions. Recommendations are made and research needs defined as a result of this review.

  17. Dose and batch-dependent hepatobiliary toxicity of 10 nm silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Marcella De Maglie


    Full Text Available Silver nanoparticles (AgNPs are widely used because of their antimicrobial properties in medical devices and in a variety of consumer products. The extensive use of AgNPs raises concerns about their potential toxicity, although it is still difficult to draw definite conclusions about their toxicity based on published data. Our preliminary studies performed to compare the effect of the AgNPs size (10-40-100 nm on toxicity, demonstrated that the smallest AgNPs determine the most severe toxicological effects. In order to best investigate the impact of physicochemical characteristics of 10 nm AgNPs on toxicity, we compare three different batches of 10 nm AgNPs slightly different in size distribution (Batch A: 8.8±1.7 nm; Batch B: 9.4±1.7 nm; Batch C: 10.0±1.8 nm. Mice were intravenously treated with two doses (5 and 10 mg/kg of the 3 AgNPs. 24 hours after the treatment, mice were euthanized and underwent complete necropsy. Tissues were collected for histopathological examination and total silver content was determined in tissues by inductively coupled plasma mass spectrometry (ICP-MS. All batches induced severe hepatobiliary lesions, i.e. marked hepatocellular necrosis and massive hemorrhage of the gall bladder. The toxicity was dose-dependent and interestingly, the toxic effects were more severe in mice treated with batches A and B that contained smaller AgNPs. Since the total silver mass concentration was similar, the observed batch-dependent toxicity suggest that even subtle differences in size may contribute to relevant changes in the toxicological outcomes, confirming the fundamental involvement of physicochemical features with respect to toxicity.

  18. An experiment teaching method based on the Optisystem simulation platform (United States)

    Zhu, Jihua; Xiao, Xuanlu; Luo, Yuan


    The experiment teaching of optical communication system is difficult to achieve because of expensive equipment. The Optisystem is optical communication system design software, being able to provide such a simulation platform. According to the characteristic of the OptiSystem, an approach of experiment teaching is put forward in this paper. It includes three gradual levels, the basics, the deeper looks and the practices. Firstly, the basics introduce a brief overview of the technology, then the deeper looks include demoes and example analyses, lastly the practices are going on through the team seminars and comments. A variety of teaching forms are implemented in class. The fact proves that this method can not only make up the laboratory but also motivate the students' learning interest and improve their practical abilities, cooperation abilities and creative spirits. On the whole, it greatly raises the teaching effect.

  19. Teaching & Learning Tips 1: Teaching perspectives - an introduction. (United States)

    Rana, Jasmine; Burgin, Susan


    Challenge: Clinical and research responsibilities often leave little or no time to plan thoughtful teaching encounters with trainees. This "Teaching & Learning Tips" series is designed to be an accessible guide for dermatologists who want to improve their teaching skills. It is comprised of 12 articles about how to enhance teaching in various settings informed by research about how people learn and expert-derived or data-driven best practices for teaching. The series begins with a review of principles to optimize learning in any setting, including cognitive load theory, active learning strategies, and the impact of motivation and emotion on learning. It transitions into a practical "how to" guide format for common teaching scenarios in dermatology, such as lecturing, case-based teaching, and teaching procedures, among others. Herein, we kickoff the series by unpacking assumptions about teaching and learning. What does it mean to teach and learn? © 2017 The International Society of Dermatology.

  20. Teaching Evolution in New Jersey Public High Schools: Examining the Influence of Personal Belief and Religious Background on Teaching Practices (United States)

    Smith, Carlen


    The purpose of this study was to determine relationships between New Jersey biology teachers' personal characteristics and religious backgrounds and the time spent and approach to teaching evolution. The research instrument chosen was a cross-sectional survey. Survey questions were presented in various forms: fill in, single response, Likert…

  1. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC{sub 50} values of other test models

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S., E-mail: [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India); Das, Sangita [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India)


    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC{sub 50}) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC{sub 50} values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r{sup 2}) for 17 physicochemical properties of metals or metal ions and EC{sub 50}s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK{sub sp}), softness parameter and some other physicochemical characteristics were significantly correlated with EC{sub 50}s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC{sub 50}s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  2. Characteristics of school facilities and their impact on educational process and students' work

    Directory of Open Access Journals (Sweden)

    Petrović Ivana P.


    Full Text Available Much research suggests that educational process, learning and students' performance depend on a number of factors such as personal and professional characteristics of teachers, curricula, and the quality of teaching and extra-curricular activities. In addition, the quality of educational process is closely connected to material-technical conditions of the school and the quality of teaching equipment. This mostly concerns school facilities (school buildings, classrooms, cabinets, library, other facilities, courtyard and gymnasium, equipment, furniture and teaching aids. However, quality learning and work also require favourable physical, physiological, social and psychological conditions for study. This is the reason why this paper investigates students' opinions concerning the influence of certain characteristics of school facilities (wall colours, visual aids hanging on walls, teaching aids, furniture, and other physical aspects, including the size of student's groups on the quality of study and learning, as well as whether these opinions vary according to sex, age and year of study. The data was collected by a questionnaire comprising 25 items especially designed for the needs of this investigation. There were 116 respondents, students of the Preschool Teacher Training College in Kruševac. The findings show that certain features of the space and certain physical characteristics do have impact on students' work and performance, and therefore on the quality of teaching. They also demonstrate that students' estimates and opinions vary according to age and year of study.

  3. Exploring Relationships between Presage Variables of Florida Preservice Agricultural Education Teachers Related to Teaching Contextualized Mathematics (United States)

    Stripling, Christopher T.; Roberts, T. Grady


    The purpose of this exploratory study was to investigate the relationships between mathematics ability, personal mathematics efficacy, mathematics teaching efficacy, personal teaching efficacy, and background characteristics of preservice agricultural education teachers. Data were collected for two years at the University of Florida. Fourteen…

  4. The Characteristics of the Effective Teacher in Cyprus Public High School: The Students' Perspective. (United States)

    Koutsoulis, Michalis

    This study examined the teacher characteristics that students considered important in defining teacher effectiveness, focusing on human characteristics, communication skills, and teaching and production characteristics. Students from 25 high schools in Cyprus completed the Classroom Culture Description Questionnaire. Overall, students listed 94…

  5. The Anxiety of PGSD’s Student In The Teaching of Mathemathics


    Wardana, Mahardika Darmawan Kusuma; Amir, Mohammad Faizal


    Mathematics is a subject that has characteristics which different from other subjects. Mathematics subject mostly always splurging on numbers. This causes not all university students like this subject. Many university students are anxious when meeting or even more when teaching these subject. To find out more about the anxiety of students on mathematics, the researchers conducted a research to determine the anxiety that existed in the students while teaching mathematics subject. The method us...



    Sead Rešić; Eldina Atić


    In this research, the application of contemporary teaching aids in Mathematics teaching in elementary school was analyzed from the aspect of teachers, students and parents. The application of contemporary teaching aids in Mathematics teaching was analyzed through a sample of 100 students, and attitudes about the aids were examined from the points of view of students, teachers and parents. In this research, descriptive method, questionnaire and test were used. Results of the resear...

  7. Persistent toxic substances: sources, fates and effects. (United States)

    Wong, Ming H; Armour, Margaret-Ann; Naidu, Ravi; Man, Ming


    Persistent toxic substances (PTS) include the Stockholm persistent organic pollutants, like dichlorodiphenyltrichloroethane, polychlorinated biphenyls, dioxin/furan, etc., and organometallic compounds, like organomercury, organotin, and organolead, which all share the same characteristics of being persistent, toxic, bioaccumulative, and able to travel long distances through different media. The adverse health effects of some of the emerging chemicals like pentabromodiphenyl ether, bisphenol A, and di(2-ethylhexyl)phthalate, which are widely used in daily appliances (e.g., TVs, computers, mobile phones, plastic baby bottles), have become a public health concern due to more evidence now available showing their adverse effects like disturbance of the endocrine system and cancer. This article is an attempt to review the current status of PTS in our environment, citing case studies in China and North America, and whether our existing drinking water treatment and wastewater treatment processes are adequate in removing them from water. Some management issues of these emerging chemicals of concern are also discussed.

  8. Influence of the Vaginal Microbiota on Toxic Shock Syndrome Toxin 1 Production by Staphylococcus aureus


    MacPhee, Roderick A.; Miller, Wayne L.; Gloor, Gregory B.; McCormick, John K.; Hammond, Jo-Anne; Burton, Jeremy P.; Reid, Gregor


    Menstrual toxic shock syndrome (TSS) is a serious illness that afflicts women of premenopausal age worldwide and arises from vaginal infection by Staphylococcus aureus and concurrent production of toxic shock syndrome toxin-1 (TSST-1). Studies have illustrated the capacity of lactobacilli to reduce S. aureus virulence, including the capacity to suppress TSST-1. We hypothesized that an aberrant microbiota characteristic of pathogenic bacteria would induce the increased production of TSST-1 and...

  9. Relationships between teaching faculty and teaching librarians

    CERN Document Server

    Katz, Linda S


    Every librarian who teaches in an academic library setting understands the complexities involved in partnering with teaching faculty. Relationships Between Teaching Faculty and Teaching Librarians recounts the efforts of librarians and faculty working together in disciplines across the board to create and sustain connections crucial to the success of library instruction. This unique collection of essays examines various types of partnerships between librarians and faculty (networking, coordination, and collaboration) and addresses the big issues involved, including teaching within an academic

  10. Study on a Quality Evaluation Method for College English Classroom Teaching

    Directory of Open Access Journals (Sweden)

    Mao-hua Sun


    Full Text Available A quality evaluation method is an important means and the main basis on which to evaluate the college English classroom teaching quality of teachers. To overcome the one-sided subjectivity and resulting imprecision of the traditional classroom teaching quality evaluation method, a scientific and reasonable quality evaluation index system for college English classroom teaching is constructed. The fuzzy comprehensive evaluation method and the analytic hierarchy process method are combined to propose an improved multi-level fuzzy comprehensive evaluation model for obtaining a new college English classroom teaching quality evaluation method. In the proposed method, according to the fuzzy characteristics of a college English classroom teaching quality evaluation, the fuzzy comprehensive evaluation method is used to transform the qualitative evaluation indexes into limited quantitative evaluation indexes, then a judgment matrix is constructed to determine the weights among different levels by using the analytic hierarchy process method. Additionally, the college English classroom teaching quality is evaluated in detail. Finally, an actual case of college English classroom teaching is used to verify the effectiveness of the college English classroom teaching quality evaluation method. The results show that the proposed college English classroom teaching method can overcome the subjectivity and randomness shortcomings of the traditional classroom teaching quality evaluation methods, and improve the reliability, accuracy, and objectivity of fuzzy comprehensive evaluation. It is an effective method to evaluate college English classroom teaching quality.

  11. The application of network teaching in applied optics teaching (United States)

    Zhao, Huifu; Piao, Mingxu; Li, Lin; Liu, Dongmei


    Network technology has become a creative tool of changing human productivity, the rapid development of it has brought profound changes to our learning, working and life. Network technology has many advantages such as rich contents, various forms, convenient retrieval, timely communication and efficient combination of resources. Network information resources have become the new education resources, get more and more application in the education, has now become the teaching and learning tools. Network teaching enriches the teaching contents, changes teaching process from the traditional knowledge explanation into the new teaching process by establishing situation, independence and cooperation in the network technology platform. The teacher's role has shifted from teaching in classroom to how to guide students to learn better. Network environment only provides a good platform for the teaching, we can get a better teaching effect only by constantly improve the teaching content. Changchun university of science and technology introduced a BB teaching platform, on the platform, the whole optical classroom teaching and the classroom teaching can be improved. Teachers make assignments online, students learn independently offline or the group learned cooperatively, this expands the time and space of teaching. Teachers use hypertext form related knowledge of applied optics, rich cases and learning resources, set up the network interactive platform, homework submission system, message board, etc. The teaching platform simulated the learning interest of students and strengthens the interaction in the teaching.

  12. Development and practice for a PACS-based interactive teaching model for CT image

    International Nuclear Information System (INIS)

    Tian Junzhang; Jiang Guihua; Zheng Liyin; Wang Ling; Wenhua; Liang Lianbao


    Objective: To explore the interactive teaching model for CT imaging based on PACS, and provide the clinician and young radiologist with continued medical education. Methods: 100 M trunk net was adopted in PACS and 10 M was exchanged on desktop. Teaching model was installed in browse and diagnosis workstation. Teaching contents were classified according to region and managed according to branch model. Text data derived from authoritative textbooks, monograph, and periodicals. Imaging data derived from cases proved by pathology and clinic. The data were obtained through digital camera and scanner or from PACS. After edited and transformed into standard digital image through DICOM server, they were saved in HD of PACS image server with file form. Results: Teaching model for CT imaging provided kinds of cases of CT sign, clinic characteristics, pathology and distinguishing diagnosis. Normal section anatomy, typical image, and its notation could be browsed real time. Teaching model for CT imaging could provide reference to teaching, diagnosis and report. Conclusion: PACS-based teaching model for CT imaging could provide interactive teaching and scientific research tool and improve work quality and efficiency

  13. Toxicity of power vehicles exhaust gases using bio fuels of different composition

    International Nuclear Information System (INIS)

    Kalnins, I.; Berjoza, D.


    The aim of the work is to state the influence of different bio fuels on the surrounding environment using them in diesel motors. The work summarises information on the composition of toxic components in vehicle exhaust gases, their influence on the surrounding environment. Characteristic features of different biofuels are summarised as well as their application possibilities in diesel motors. Measuring devices and measuring methods of toxic components of exhaust gases have been classified. Different measuring regimes of diesel motor exhaust gases have been described. Research in automobile Renault, equipped with diesel motor, exhaust gas smokiness using different biofuels has been carried out (author)

  14. Medical Audit: A Nigerian Teaching Hospital's Preliminary Experience

    African Journals Online (AJOL)

    The definition, historical background, aims dimensions and the characteristics of medical audit as well as the indices to be measured in a medical audit exercise are highlighted. The preliminary experience of the University of Ilorin Teaching Hospital (UITH) in the planning, implementation and monitoring of a viable medical ...

  15. What Do College Students Want? A Prioritization of Instructional Behaviors and Characteristics (United States)

    Goldman, Zachary W.; Cranmer, Gregory A.; Sollitto, Michael; Labelle, Sara; Lancaster, Alexander L.


    Guided by Rhetorical and Relational Goals Theory, this study examined college students' preferences for effective teaching behaviors and characteristics. Students (n = 209) articulated qualities in their ideal instructor by prioritizing 10 instructional behaviors and characteristics from the rhetorical and relational traditions (assertive,…

  16. Toxicity and response in cats with neoplasia treated with toceranib phosphate. (United States)

    Harper, Aaron; Blackwood, Laura


    Objectives Toceranib phosphate is a tyrosine kinase inhibitor licensed for the treatment of non-resectable Patnaik grade II/III recurrent cutaneous mast cell tumours in dogs. There is no information in cats regarding the tolerated dose, toxicity or tumour response of this drug. The aim of this study was to analyse retrospectively a cohort of cats with advanced neoplasia treated with toceranib to identify toxicity and response. Methods The medical records of the Small Animal Teaching Hospital were reviewed. Cats were included if they had received toceranib for at least 2 weeks for the treatment of histologically or cytologically confirmed neoplastic disease, and had at least one set of monitoring blood tests (haematology, biochemistry) performed after baseline tests. Toxicity was graded according to the Veterinary Comparative Oncology Group - common terminology criteria for adverse events(VCOG-CTCAE) and response was measured according to Response Evaluation In Solid Tumors (RECIST) criteria. Results Fourteen cats met the inclusion criteria, the majority of which (13/14) had received previous therapy (surgery, radiotherapy, chemotherapy). The most common tumour types were mast cell tumours or malignant epithelial tumours. Toxicity occurred in 10/14 cats - 10 cats had mild myelosuppression or gastrointestinal effects. Two cats developed severe hepatoxicity. One cat died from congestive heart failure, although whether this was related to toceranib therapy is unknown. Regarding response, one cat achieved complete response; two cats achieved partial response and five cats achieved stable disease: overall biological response rate was 57.1%. All of the cats that achieved either partial or complete response were treated for mast cell disease. Overall median duration of response was 90 days (range 14-570 days). None of the cats with squamous cell carcinoma achieved a response. Conclusions and relevance Toceranib phosphate is generally well tolerated in cats, with toxicity

  17. Teaching Density Functional Theory Through Experiential Learning

    International Nuclear Information System (INIS)

    Narasimhan, Shobhana


    Today, quantum mechanical density functional theory is often the method of choice for performing accurate calculations on atomic, molecular and condensed matter systems. Here, I share some of my experiences in teaching the necessary basics of solid state physics, as well as the theory and practice of density functional theory, in a number of workshops held in developing countries over the past two decades. I discuss the advantages of supplementing the usual mathematically formal teaching methods, characteristic of graduate courses, with the use of visual imagery and analogies. I also describe a successful experiment we carried out, which resulted in a joint publication co-authored by 67 lecturers and students participating in a summer school. (paper)

  18. Teaching Abroad: Why Teachers Prefer Teaching Overseas

    Directory of Open Access Journals (Sweden)

    Mustafa Serbes


    Full Text Available Teaching overseas has always been a great opprotunity for academic and social development. Teachers who have international experiences stand a better chance of not only developing their teaching skills, communication skills and classroom management but also learning new languages and about other cultures. Teaching abroad can help teachers promote their skills for efficiency and effectiveness. It is important to stress that teachers with international experience can teach effectively and can contribute to the achievement of their students more. This paper focuses on five reasons why teachers prefer teaching overseas.

  19. The Teaching of Culture in English Language Teaching

    Institute of Scientific and Technical Information of China (English)



      Language is not only part of culture, but also the carrier. The relationship between them decides the important role of culture teaching in language teaching. However, some problems still exist in college English teaching. For example, classroom English teaching time is not enough for culture teaching; English learners’native language thinking has negative transfer in the target language learning, etc.. In order to solve these problems, this paper tends to discuss whether English teaching should put an emphasis on Big-C Culture or Little-c Culture.

  20. reflections from the 45th World Assembly on Education for Teaching

    African Journals Online (AJOL)

    ... economic growth, they impact on the expectations for quality education and training. ... Against this background, education for teaching in a globalised economic ... characteristics that pose a major challenge to higher education institutions.

  1. Evaluation of Teaching Performance: Considerations from the Competency-Based Approach

    Directory of Open Access Journals (Sweden)

    Mario Rueda Beltrán


    Full Text Available The article gives an overview of the main arguments and characteristics attributed to the Competency-based Approach in education, so as to analyze the various definitions available and some of the proposals on the subject of teaching skills. Approaches and strategies are suggested for developing teacher-evaluation programs in the context of a generalized environment in the educational sector which is adopting the model of competencies for school reform, curriculum redesign, modifications in teaching strategies, and manners and functions of evaluation.


    Directory of Open Access Journals (Sweden)

    Luis Roberto de Camargo Ribeiro


    Full Text Available This article brings the analysis of a study—of a descriptive-analytical nature—about online tutoring, some of its characteristics and peculiarities as compared to face-to-face education. To this end it analyzes the results of an online questionnaire answered by 222 tutors pertaining to programs offered at Universidade Federal de São Carlos (UFSCar in partnership with Universidade Aberta do Brasil (UAB and Brazilian townships. The analysis focused on tutors’ characteristics (e.g., sex, education background and teaching experience, their work organization and activities, the division of labor (between tutors and teachers responsible for subjects, and their perceptions about the nature of tutoring and education at a distance (DE. This study is chiefly based on authors such as Lortie, Tardif, and Shulman—about face-to-face teaching—and Mill, Maggio, and Kenski—on distance education. The results of this study point to the predominance of female tutors, which resembles the makeup of the teaching body in face-to-face education at the lower levels, and indicate the respondents’ high levels of schooling and considerable face-to-face teaching experience. Despite the difficulties encountered by the tutors in this study, mainly due to their lack of experience in DE and varied technical problems, most of the tutors found it easy and pleasurable to work online. The dada also suggest that the tutors enjoyed comparative autonomy as regards actions associated with content transmission as well as actions related to (virtual classroom management. This autonomy may be the basis for the respondents’ perception that the online tutor, in the context under consideration, performs a genuine teaching function.

  3. The Characteristics of Successful MOOCs in the Fields of Software, Science, and Management, According to Students’ Perception

    Directory of Open Access Journals (Sweden)

    Anat Cohen


    Full Text Available The characteristics of successful MOOCs were explored in this study. Thousands of student reviews regarding five xMOOCs (Massive Open Online Course in the fields of software, science, and management were extracted from the Coursetalk website and analyzed by quantitative and qualitative methods using the Garrison, Anderson, and Archer (2000 Community of Inquiry (CoI model. The 14 characteristics found to contribute to the success of MOOCs (e.g., teacher, atmosphere, exercise were partitioned into the teaching, social, and cognitive presence elements. In addition, cluster analysis revealed five types of learners, based on the characteristics they mentioned for course success: atmosphere, exercise, teacher, exam, and unspecified. This divides learners into groups that may prefer social, cognitive, or teaching presence. The findings of this study negate the perception that xMOOCs mostly contain teaching presence elements. This research contributes to the understanding of characteristics that contribute to successful MOOCs and sheds light on the students, too. Listening to the voices of the students and the types of characteristics that they chose to mention, enables further exploration of their preferences and expectations regarding MOOCs and, accordingly, to future adaptation between students’ preferences and MOOC characteristics.

  4. Mixture toxicity of wood preservative products in the fish embryo toxicity test. (United States)

    Coors, Anja; Dobrick, Jan; Möder, Monika; Kehrer, Anja


    Wood preservative products are used globally to protect wood from fungal decay and insects. We investigated the aquatic toxicity of five commercial wood preservative products, the biocidal active substances and some formulation additives contained therein, as well as six generic binary mixtures of the active substances in the fish embryo toxicity test (FET). Median lethal concentrations (LC50) of the single substances, the mixtures, and the products were estimated from concentration-response curves and corrected for concentrations measured in the test medium. The comparison of the experimentally observed mixture toxicity with the toxicity predicted by the concept of concentration addition (CA) showed less than twofold deviation for all binary mixtures of the active substances and for three of the biocidal products. A more than 60-fold underestimation of the toxicity of the fourth product by the CA prediction was detected and could be explained fully by the toxicity of one formulation additive, which had been labeled as a hazardous substance. The reason for the 4.6-fold underestimation of toxicity of the fifth product could not be explained unambiguously. Overall, the FET was found to be a suitable screening tool to verify whether the toxicity of formulated wood preservatives can reliably be predicted by CA. Applied as a quick and simple nonanimal screening test, the FET may support approaches of applying component-based mixture toxicity predictions within the environmental risk assessment of biocidal products, which is required according to European regulations. Copyright © 2012 SETAC.

  5. Predicting molybdenum toxicity to higher plants: Estimation of toxicity threshold values

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, S.P., E-mail: [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Mico, C.; Zhao, F.J.; Stroud, J.L. [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Zhang, H.; Fozard, S. [Division of Environmental Science, Lancaster University, Lancaster LA1 4YQ (United Kingdom)


    Four plant species (oilseed rape, Brassica napus L.; red clover, Trifolium pratense L.; ryegrass, Lolium perenne L.; and tomato, Lycopersicon esculentum L.) were tested on ten soils varying widely in soil properties to assess molybdenum (Mo) toxicity. A larger range (66-fold-609-fold) of added Mo concentrations resulting in 50% inhibition of yield (ED{sub 50}) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of Mo toxicity. Toxicity thresholds based on soil solution Mo narrowed the variation among soils compared to thresholds based on added Mo concentrations. We conclude that plant bioavailability of Mo in soil depends on Mo solubility, but this alone did not decrease the variability in observed toxicity enough to be used in risk assessment and that other soil properties influencing Mo toxicity to plants need to be considered. - Mo toxicity thresholds varied widely in different soils and therefore soil properties need to be taken into account in order to assess the risk of Mo exposure.

  6. Earthworm nano‐ecotoxicology: Towards an integrated approach in toxicity testing of metal nanoparticles

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Pedersen, Henrik; Wang, Jing

    Manufactured nanoparticles (NPs) belong to an emerging class of potential environmental pollutants. Of particular interest are the characteristics of NP toxicity under different exposure conditions e.g. cell culture, aquatic or soil media. NPs are thought to behave differently depending on the me...

  7. Patient characteristics upon initial presentation to chiropractic teaching clinics: A descriptive study conducted at one university (United States)

    Kaeser, Martha A.; Hawk, Cheryl; Anderson, Michelle


    Objective The purpose of this study was to compare demographics and chief complaints of the new patient population at our institution's fee-for-service clinics to the patient population of practicing chiropractors in the United States. We also compared the prevalence of obesity and hypertension to reference standards for the adult population. Methods Patient data were obtained from the electronic health records. All records identified as new patients during October 2013 were included. Variables of interest were clinic site, patient demographics, blood pressure, body mass index (BMI), chief complaint, and ICD-9 codes. Descriptive statistics were computed and compared to reference standards from previous reports. Results During October 2013, there were 224 new patients that entered the clinics. The average patient was a 31- to 50-year-old white male. Our clinic patients differed from those seen by US chiropractors in the distribution of all demographic variables. For adult patients, 31.4% were overweight, 29% were obese, and 8% stage 1 or 2 hypertension. Conclusion New patients in the fee-for-service teaching clinics appear to be dissimilar to those of US practicing chiropractors in several important demographics, characteristics, and types of complaints. The new patients had lower levels of overweight, obesity, and hypertension compared to US reference standards. PMID:25162982

  8. Teach First Norway - who joins and what are their initial motivations for teaching?

    Directory of Open Access Journals (Sweden)

    Katrine Nesje


    investigates specific characteristics of the professional motivations of candidates recruited to these programmes. The article reports both the motivations for teaching and reasons for attending the alternative teacher education programme Teach First Norway (TFN. For descriptive purposes a cluster analysis was performed based on survey data from one cohort (N=13 of TFN candidates. Three motivational profiles emerged: ‘low altruistic motivation’, ‘high interest in teaching’ and ‘predominant altruistic motivation’. The profiles were further explored through qualitative interviews.  The results show that the interplay between participants’ motivations is complex and unique. The stereotypical image of a TFN candidate that uses the programme as a springboard into management positions in businesses becomes more nuanced as a result of these findings.Keywords: alternative teacher education, motivations to teach, careers, Teach First

  9. Oilseed rape genotypes response to boron toxicity

    Directory of Open Access Journals (Sweden)

    Savić Jasna


    Full Text Available Response of 16 oilseed rape genotypes to B (boron toxicity was analyzed by comparing the results of two experiments conducted in a glasshouse. In Experiment 1 plants were grown in standard nutrient solutions with 10 µMB (control and 1000 µM B. Relative root and shoot growth varied from 20-120% and 31-117%, respectively. Variation in B concentration in shoots was also wide (206.5-441.7 µg B g-1 DW as well as total B uptake by plant (62.3-281.2 µg B g1. Four selected genotypes were grown in Experiment 2 in pots filled with high B soil (8 kg ha-1 B; B8. Shoot growth was not affected by B8 treatment, while root and shoot B concentration was significantly increased compared to control. Genotypes Panther and Pronto which performed low relative root and shoot growth and high B accumulation in plants in Experiment 1, had good growth in B8 treatment. In Experiment 2 genotype NS-L-7 had significantly lower B concentration in shots under treatment B8, but also very high B accumulation in Experiment 1. In addition, cluster analyses classified genotypes in three groups according to traits contrasting in their significance for analyzing response to B toxicity. The first group included four varieties based on their shared characteristics that have small value for the relative growth of roots and shoots and large values of B concentration in shoot. In the second largest group were connected ten genotypes that are heterogeneous in traits and do not stand out on any characteristic. Genotypes NS-L-7 and Navajo were separated in the third group because they had big relative growth of root and shoot, but also a high concentration of B in the shoot, and high total B uptake. Results showed that none of tested genotypes could not be recommended for breeding process to tolerance for B toxicity. [Projekat Ministarstva nauke Republike Srbije, br. OI 173028

  10. Evaluation on the Toxic Effects of NanoAg to Catalase. (United States)

    Zhang, Bin; Zhai, Wenxin; Liu, Rutao; Yu, Zehua; Shen, Hengmei; Hu, Xinxin


    Protein is the functional actor of life. Research on protein damage induced by nanomaterials may give insight into the toxicity mechanisms of nanoparticles. Studying nano silver over the impact of the structure and function of catalase (CAT) at the molecular level, is of great significance for a comprehensive evaluation of their toxic effects. The toxic effects of nanoAg on catalase were thoroughly investigated using steady state and time resolved fluorescence quenching measurements, ultraviolet-visible absorption spectroscopy, resonance light scattering spectroscopy (RLS), circular dichroism spectroscopy (CD) and transmission electron microscopy (TEM). NanoAg could decrease the amount of alpha-helix and increase the beta sheet structure, leading to loose the skeleton structure of catalase. The characteristic fluorescence of catalase was obviously quenched, which showed the exposal of internal hydrophobic amino acids enhanced, and its quenching type is dynamic quenching. The result of RLS and TEM showed that the distribution and size of nanoAg become more uniform and smaller after their interaction, resulting in a decrease of RLS intensity. NanoAg could make the activity of catalase rise. By changing the structure of catalase, nanoAg increases its enzymatic activity to a certain extent, breaking down its balance in vivo, thereby affecting the normal physiological activities. NanoAg has obvious toxic effects on catalase. This paper provided a new perspective and method for the toxic effects of nanoAg to biological macromolecules; provided basic data and reference gist for the hygienics and toxicology studies of nanoAg. It is conducive to the toxicity prevention and control work of nanoAg, promoting nano-technology applied to human production and living better.

  11. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Nowell, Lisa H., E-mail: [U.S. Geological Survey, California Water Science Center, Placer Hall, 6000 J Street, Sacramento, CA 95819 (United States); Norman, Julia E., E-mail: [U.S. Geological Survey, Oregon Water Science Center, 2130 SW 5" t" h Avenue, Portland, OR 97201 (United States); Ingersoll, Christopher G., E-mail: [U.S. Geological Survey, Columbia Environmental Research Center, 4200 New Haven Road, Columbia, MO 65021 (United States); Moran, Patrick W., E-mail: [U.S. Geological Survey, Washington Water Science Center, 934 Broadway, Suite 300, Tacoma, WA 98402 (United States)


    Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides in whole sediment. The Likely Effect Benchmark (LEB) defines a pesticide concentration in whole sediment above which there is a high probability of adverse effects on benthic invertebrates, and the Threshold Effect Benchmark (TEB) defines a concentration below which adverse effects are unlikely. For compounds without available SSBs, benchmarks were estimated using equilibrium partitioning (EqP). When a sediment sample contains a pesticide mixture, benchmark quotients can be summed for all detected pesticides to produce an indicator of potential toxicity for that mixture. Benchmarks were developed for 48 pesticide compounds using SSB data and 81 compounds using the EqP approach. In an example application, data for pesticides measured in sediment from 197 streams across the United States were evaluated using these benchmarks, and compared to measured toxicity from whole-sediment toxicity tests conducted with the amphipod Hyalella azteca (28-d exposures) and the midge Chironomus dilutus (10-d exposures). Amphipod survival, weight, and biomass were significantly and inversely related to summed benchmark quotients, whereas midge survival, weight, and biomass showed no relationship to benchmarks. Samples with LEB exceedances were rare (n = 3), but all were toxic to amphipods (i.e., significantly different from control). Significant toxicity to amphipods was observed for 72% of samples exceeding one or more TEBs, compared to 18% of samples below all TEBs. Factors affecting toxicity below TEBs may include the presence of contaminants other than pesticides, physical/chemical characteristics

  12. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides

    International Nuclear Information System (INIS)

    Nowell, Lisa H.; Norman, Julia E.; Ingersoll, Christopher G.; Moran, Patrick W.


    Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides in whole sediment. The Likely Effect Benchmark (LEB) defines a pesticide concentration in whole sediment above which there is a high probability of adverse effects on benthic invertebrates, and the Threshold Effect Benchmark (TEB) defines a concentration below which adverse effects are unlikely. For compounds without available SSBs, benchmarks were estimated using equilibrium partitioning (EqP). When a sediment sample contains a pesticide mixture, benchmark quotients can be summed for all detected pesticides to produce an indicator of potential toxicity for that mixture. Benchmarks were developed for 48 pesticide compounds using SSB data and 81 compounds using the EqP approach. In an example application, data for pesticides measured in sediment from 197 streams across the United States were evaluated using these benchmarks, and compared to measured toxicity from whole-sediment toxicity tests conducted with the amphipod Hyalella azteca (28-d exposures) and the midge Chironomus dilutus (10-d exposures). Amphipod survival, weight, and biomass were significantly and inversely related to summed benchmark quotients, whereas midge survival, weight, and biomass showed no relationship to benchmarks. Samples with LEB exceedances were rare (n = 3), but all were toxic to amphipods (i.e., significantly different from control). Significant toxicity to amphipods was observed for 72% of samples exceeding one or more TEBs, compared to 18% of samples below all TEBs. Factors affecting toxicity below TEBs may include the presence of contaminants other than pesticides, physical/chemical characteristics

  13. Aquatic toxicity testing of silver nanoparticles – a matter of timing

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Owsianiak, Mikolaj; Engelbrekt, Christian

    , and difficulties in controlling and/or describing the characteristics of the tested NPs. These issues may be related to the widespread approach of using freshly prepared stock solutions for ecotoxicity testing, as the introduction of NPs into aqueous media initiates time-dependent processes that possibly interfere...... of the test. Ultimately, the aim is better control of the AgNPs in the algal test system and improved prerequisites for describing their toxicity to alga. The underlying hypothesis is that a large part in the variability of AgNPs toxicity to algae can be explained by the kinetics of dissolution and speciation...... of Ag ions in the test media. To reduce the amount of time in which changes to NPs may occur during testing, the exposure period was minimized. A recently proposed short-term (2h) algal test was applied, using 14C incorporation during photosynthesis as toxic endpoint [1]. For citrate coated spherical Ag...

  14. Product consistency test and toxicity characteristic leaching procedure results of the ceramic waste form from the electrometallurgical treatment process for spent fuel

    International Nuclear Information System (INIS)

    Johnson, S. G.; Adamic, M. L.: DiSanto, T.; Warren, A. R.; Cummings, D. G.; Foulkrod, L.; Goff, K. M.


    The ceramic waste form produced from the electrometallurgical treatment of sodium bonded spent fuel from the Experimental Breeder Reactor-II was tested using two immersion tests with separate and distinct purposes. The product consistency test is used to assess the consistency of the waste forms produced and thus is an indicator of a well-controlled process. The toxicity characteristic leaching procedure is used to determine whether a substance is to be considered hazardous by the Environmental Protection Agency. The proposed high level waste repository will not be licensed to receive hazardous waste, thus any waste forms destined to be placed there cannot be of a hazardous nature as defined by the Resource Conservation and Recovery Act. Results are presented from the first four fully radioactive ceramic waste forms produced and from seven ceramic waste forms produced from cold surrogate materials. The fully radioactive waste forms are approximately 2 kg in weight and were produced with salt used to treat 100 driver subassemblies of spent fuel

  15. Graduate teaching assistants' perceptions of teaching competencies required for work in undergraduate science labs (United States)

    Deacon, Christopher; Hajek, Allyson; Schulz, Henry


    Many post-secondary institutions provide training and resources to help GTAs fulfil their teaching roles. However, few programmes focus specifically on the teaching competencies required by GTAs who work with undergraduate students in laboratory settings where learning tends to be more active and inquiry based than in classroom settings. From a review of 8 GTA manuals, we identified 20 competencies and then surveyed faculty and lab coordinators (FIS) and GTAs from a Faculty of Science at a comprehensive Canadian university to identify which of those competencies are required of GTAs who work in undergraduate science labs. GTAs and FIS did not significantly differ in the competencies they view as required for GTAs to work effectively in undergraduate labs. But, when comparing the responses of GTAs and FIS to TA manuals, 'Clearly and effectively communicates ideas and information with students' was the only competency for which there was agreement on the level of requirement. We also examined GTAs' self-efficacy for each of the identified competencies and found no overall relationship between self-efficacy and demographic characteristics, including experience and training. Our results can be used to inform the design of training programmes specifically for GTAs who work in undergraduate science labs, for example, programmes should provide strategies for GTAs to obtain feedback which they can use to enhance their teaching skills. The goal of this study is to improve undergraduate lab instruction in faculties of science and to enhance the teaching experience of GTAs by better preparing them for their role.

  16. Teaching psychology to computing students


    Taylor, Jacqui


    The aim of this paper is twofold. The first aim is to discuss some observations gained from teaching Psychology to Computing students, highlighting both the wide range of areas where Psychology is relevant to Computing education and the topics that are relevant at different stages of students’ education. The second aim is to consider findings from research investigating the characteristics of Computing and Psychology students. It is proposed that this information could be considered in the de...

  17. General informatics teaching with B-Learning teaching model

    Directory of Open Access Journals (Sweden)

    Nguyen The Dung


    Full Text Available Blended learning (B-learning, a combination of face-to-face teaching and E-learning-supported-teaching in an online course, and Information and Communication Technology (ICT tools have been studied in recent years. In addition, the use of this teaching model is effective in teaching and learning conditions in which some certain subjects are appropriate for the specific teaching context. As it has been a matter of concern of the universities in Vietnam today, deep studies related to this topic is crucial to be conducted. In this article, the process of developing online courses and organizing teaching for the General Informatics subject for first-year students at the Hue University of Education with B-learning teaching model will be presented. The combination of 60% face-to-face and 40% online learning.

  18. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen


    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors to h...

  19. 3. Phenotypic Characteristics of Zambian patients with Parkinson's

    African Journals Online (AJOL)


    ABSTRACT. Objective: To describe the phenotypic characteristics of adult Zambian patients with newly diagnosed Parkinson's disease (PD) at University Teaching Hospital (UTH). Background: The genetic basis of idiopathic Parkinson's disease is remains unknown. Little information is available regarding the genotype and ...

  20. The Literal Translation Hypothesis in ESP Teaching/Learning Environments

    Directory of Open Access Journals (Sweden)

    Pedro A. Fuertes-Olivera


    Full Text Available Research on the characteristics of specialized vocabulary usually replicates studies that deal with general words, e.g. they typically describe frequent terms and focus on their linguistic characteristics to aid in the learning and acquisition of the terms. We dispute this practise, as we believe that the basic characteristic of terms is that they are coined to restrict meaning, i.e. to be as precise and as specific as possible in a particular context. For instance, around 70% of English and Spanish accounting terms are multi-word terms, most of which contain more than three orthographic words that syntactically behave in a way that is very different from the syntactic behaviour of the node on which they are formed (Fuertes-Olivera and Tarp, forthcoming. This has prompted us to propose a research framework that investigates whether or not the literal translation hypothesis, which has been addressed in several areas of translation studies, can also be applied in ESP teaching/learning environments. If plausible, the assumptions on which this hypothesis is based can shed light on how learners disambiguate terms they encounter. Within this framework, this paper presents evidence that the literal translation hypothesis is possible in ESP; it offers the results of a pilot study that sheds light on how this hypothesis may work, and also discusses its usability in the context of ESP learning. In particular, this paper presents strategies for teaching multi-word terms that are different from those currently based on corpus data. We believe that exercises such as “cloze”, “fill in” and similar “guessing” exercises must be abandoned in ESP teaching/learning environments. Instead, we propose exercises that reproduce L1 teaching and learning activities, i.e., exercises that are typically used when acquiring specialised knowledge and skills in any domain, e.g. taking part in meetings and giving presentations in a business context.

  1. What the Student Does: Teaching for Enhanced Learning (United States)

    Biggs, John


    Many teachers see major difficulties in maintaining academic standards in today's larger and more diversified classes. The problem becomes more tractable if learning outcomes are seen as more a function of students' activities than of their fixed characteristics. The teacher's job is then to organise the teaching/learning context so that all…

  2. Teaching methods in PE teaching


    Šekeljić, Goran V.; Stamatović, Milovan V.


    The methods used in teaching physical education, as well as in every other very specific teaching area, have their own uniqueness and enormous importance in teaching. In the last fifty years literature showed many different methods systematized by several different criteria. Some were just taken from general didactics, some were tailored to the needs of physical education classes, and a few new ones were discovered. The special value of this work is that the existing methods are supplemented ...

  3. Amyloid-linked cellular toxicity triggered by bacterial inclusion bodies

    International Nuclear Information System (INIS)

    Gonzalez-Montalban, Nuria; Villaverde, Antonio; Aris, Anna


    The aggregation of proteins in the form of amyloid fibrils and plaques is the characteristic feature of some pathological conditions ranging from neurodegenerative disorders to systemic amyloidoses. The mechanisms by which the aggregation processes result in cell damage are under intense investigation but recent data indicate that prefibrillar aggregates are the most proximate mediators of toxicity rather than mature fibrils. Since it has been shown that prefibrillar forms of the nondisease-related misfolded proteins are highly toxic to cultured mammalian cells we have studied the cytoxicity associated to bacterial inclusion bodies that have been recently described as protein deposits presenting amyloid-like structures. We have proved that bacterial inclusion bodies composed by a misfolding-prone β-galactosidase fusion protein are clearly toxic for mammalian cells but the β-galactosidase wild type enzyme forming more structured thermal aggregates does not impair cell viability, despite it also binds and enter into the cells. These results are in the line that the most cytotoxic aggregates are early prefibrilar assemblies but discard the hypothesis that the membrane destabilization is Key event to subsequent disruption of cellular processes, such as ion balance, oxidative state and the eventually cell death

  4. Use and toxicity of traditional and complementary medicine among patients seeking care at an emergency department of a teaching hospital in Malaysia. (United States)

    Jatau, Abubakar Ibrahim; Aung, Myat Moe Thwe; Kamauzaman, Tuan Hairulnizam Tuan; Ab Rahman, Ab Fatah


    Traditional and Complementary Medicines (TCM) are widely used worldwide, and many of them have the potential to cause toxicity, interaction with conventional medications and non-adherence to prescribed medications due to patients' preference for the TCM use. However, information regarding their use among patients seeking care at emergency departments (ED) of a healthcare facility is limited. The study aimed to evaluate the TCM use among patients attending the ED of a teaching hospital in Malaysia. A sub-analysis of data from a prevalence study of medication-related visits among patients at the ED of Hospital Universiti Sains Malaysia was conducted. The study took place over a period of six weeks from December 2014 to January 2015 involving 434 eligible patients. Data on demography, conventional medication, and TCM uses were collected from patient interview and the medical folders. Among this cohort, 66 patients (15.2%, 95%CI 12.0, 19.0) reported concurrent TCM use. Sixteen (24.2%) of the TCM users were using more than one (1) type of TCM, and 17 (25.8%) came to the ED for medication-related reasons. Traditional Malay Medicine (TMM) was the most frequently used TCM by the patients. Five patients (7.6%) sought treatment at the ED for medical problems related to use of TCM. Patients seeking medical care at the ED may be currently using TCM. ED-physicians should be aware of these therapies and should always ask patients about the TCM use. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. A Case Study of Effective Practice in Mathematics Teaching and Learning Informed by Valsiner's Zone Theory (United States)

    Geiger, Vince; Anderson, Judy; Hurrell, Derek


    The characteristics that typify an effective teacher of mathematics and the environments that support effective teaching practices have been a long-term focus of educational research. In this article we report on an aspect of a larger study that investigated "best practice" in mathematics teaching and learning across all Australian…

  6. Characteristics and determinants of adult patients with acute poisoning attending the accident and emergency department of a teaching hospital in Qatar. (United States)

    Khudair, I F; Jassim, Z; Hanssens, Y; Alsaad, W A


    Data about etiologic and demographic characteristics of acute poisoning in adults in Qatar are lacking. This prospective observational study was undertaken to analyze characteristics and possible determinants of acute poisoning in adults in Qatar. During 2010, 18,073 patients attended the emergency department of Hamad General Hospital, a teaching hospital in Qatar. Out of them, 599 (3.3%) patients were diagnosed as "poisoning case" with either chemical or pharmaceutical substances. The prevalence rate of poisoning incidence was 35.3/100,000 population. Seven patients died, corresponding with a case-fatality rate of 0.39/1000. The majority were male (65%) and the mean age was 34 years. The poisons involved were mainly chemicals (61.6%) and pharmaceuticals (38.4%). Female, mainly single, suffered more intentional poisoning compared to male. Of the patients aged 60 years and above (7.2%), the majority (95.3%) suffered unintentional poisoning with pharmaceuticals; 56% with warfarin, 12% with digoxin and 7% with insulin. Multivariate analysis shows that female gender, single status, younger than 35 years of age, being poisoned by pharmaceutical products, and the need for hospitalization are significant determinants for acute intentional poisoning after adjusting all other possible covariates. The findings of this study can be used to establish awareness and prophylactic campaigns in Qatar.

  7. Random Forests to Predict Rectal Toxicity Following Prostate Cancer Radiation Therapy

    International Nuclear Information System (INIS)

    Ospina, Juan D.; Zhu, Jian; Chira, Ciprian; Bossi, Alberto; Delobel, Jean B.; Beckendorf, Véronique; Dubray, Bernard; Lagrange, Jean-Léon; Correa, Juan C.


    Purpose: To propose a random forest normal tissue complication probability (RF-NTCP) model to predict late rectal toxicity following prostate cancer radiation therapy, and to compare its performance to that of classic NTCP models. Methods and Materials: Clinical data and dose-volume histograms (DVH) were collected from 261 patients who received 3-dimensional conformal radiation therapy for prostate cancer with at least 5 years of follow-up. The series was split 1000 times into training and validation cohorts. A RF was trained to predict the risk of 5-year overall rectal toxicity and bleeding. Parameters of the Lyman-Kutcher-Burman (LKB) model were identified and a logistic regression model was fit. The performance of all the models was assessed by computing the area under the receiving operating characteristic curve (AUC). Results: The 5-year grade ≥2 overall rectal toxicity and grade ≥1 and grade ≥2 rectal bleeding rates were 16%, 25%, and 10%, respectively. Predictive capabilities were obtained using the RF-NTCP model for all 3 toxicity endpoints, including both the training and validation cohorts. The age and use of anticoagulants were found to be predictors of rectal bleeding. The AUC for RF-NTCP ranged from 0.66 to 0.76, depending on the toxicity endpoint. The AUC values for the LKB-NTCP were statistically significantly inferior, ranging from 0.62 to 0.69. Conclusions: The RF-NTCP model may be a useful new tool in predicting late rectal toxicity, including variables other than DVH, and thus appears as a strong competitor to classic NTCP models

  8. Student Perceptions of Effective Clinical Teaching Characteristics in Dental Hygiene Programs in Northeastern States (United States)

    Bearor, Dawn E.


    The clinical education component provided to dental hygiene students is an essential part of their development as competent practitioners. Instructor approaches to clinical teaching are therefore critical in providing quality clinical learning experiences. This study sought to identify dental hygiene students' perceptions of "best" and…

  9. New insights into parental effects and toxicity: Mate availability and diet in the parental environment affect offspring responses to contaminants

    International Nuclear Information System (INIS)

    Plautz, Stephanie C.; Funkhouser, Meghan A.; Salice, Christopher J.


    Parental effects manifest as alterations in offspring phenotype resulting from the parental phenotype and/or parental environment. We evaluated the effects of parental diet quality and mating strategy on the toxicant tolerance of offspring in Biomphalaria glabrata snails. We raised snails either individually (self-fertilizing) or in groups of three (outcrossing) on a diet of uncooked lettuce, fish food, cooked lettuce, or cooked lettuce plus fish food. We then exposed their offspring to cadmium and malathion challenges. Cadmium tolerance varied with parental diet and was greater in the offspring of outcrossing snails than self-fertilizing snails. Malathion tolerance was not affected by parental diet but was greater in the offspring of outcrossing snails. These results indicate that offspring responses to stressors are heavily influenced by parental experience, but may depend on the specific stressor and the mechanism of action and/or detoxification. -- Highlights: •We reared parental snails either alone or in groups and fed them one of four diets. •We exposed their juvenile offspring to cadmium and malathion survival challenges. •Outcrossing increased toxicant tolerance of juveniles compared to self-fertilizing. •Parental diet affected juvenile offspring tolerance to cadmium but not malathion. •Toxicant characteristics likely influenced parental effects on toxicant tolerance. -- Both parental diet composition and mating strategy can significantly alter the toxicant tolerance of offspring, and toxicant characteristics likely influence the probability of parental effects

  10. A toxicity reduction evaluation for an oily waste treatment plant exhibiting episodic effluent toxicity. (United States)

    Erten-Unal, M; Gelderloos, A B; Hughes, J S


    A Toxicity Reduction Evaluation (TRE) was conducted on the oily wastewater treatment plant (Plant) at a Naval Fuel Depot. The Plant treats ship and ballast wastes, berm water from fuel storage areas and wastes generated in the fuel reclamation plant utilizing physical/chemical treatment processes. In the first period of the project (Period I), the TRE included chemical characterization of the plant wastewaters, monitoring the final effluent for acute toxicity and a thorough evaluation of each treatment process and Plant operating procedures. Toxicity Identification Evaluation (TIE) procedures were performed as part of the overall TRE to characterize and identify possible sources of toxicity. Several difficulties were encountered because the effluent was saline, test organisms were marine species and toxicity was sporadic and unpredictable. The treatability approach utilizing enhancements, improved housekeeping, and operational changes produced substantial reductions in the acute toxicity of the final effluent. In the second period (Period II), additional acute toxicity testing and chemical characterization were performed through the Plant to assess the long-term effects of major unit process improvements for the removal of toxicity. The TIE procedures were also modified for saline wastewaters to focus on suspected class of toxicants such as surfactants. The TRE was successful in reducing acute toxicity of the final effluent through process improvements and operational modifications. The results indicated that the cause of toxicity was most likely due to combination of pollutants (matrix effect) rather than a single pollutant.

  11. Linguistic Ethnography, Literacy Teaching and Teacher Training

    DEFF Research Database (Denmark)

    Dolmer, Grete; Nielsen, Henrik Balle

    in current attempts to research-base teacher education. Lefstein, A. & J. Snell. 2014. Better than best practice. Developing teaching and learning through dialogue. London: Routledge. Keywords: literacy teaching classroom dialogue teacher feedback linguistic ethnography research-based teacher education...... material consists of field notes and video observations from the literacy classroom combined with reflective interviews with the literacy teacher and analyses of pupils’ oral and written texts. Taking a linguistic ethnographic approach, the case study investigates the interplay between teacher, pupil...... eclecticism, openness and systematicity characteristic of a linguistic ethnographic analysis (Lefstein & Snell 2014, 185-86). In the poster, we will focus on emergent data analysis. Our main points of interest are 1) the classroom dialogue between teacher and pupils and 2) the literacy teacher’s assessment...

  12. Teaching audience analysis to the technical student (United States)

    Debs, M. B.; Brillhart, L. V.


    Teaching audience analysis, as practiced in a technical writing course for engineering students, is discussed. Audience analysis is described as the task of defining the audience for a particular piece of writing and determining those characteristics of the audience which constrain the writer and effect reception of the message. A mature technical writing style that shows the tension produced when a text is written to be read and understood is considered in terms of audience analysis. Techniques include: (1) conveying to students the concept that a reader with certain expectations exist, (2) team teaching to preserve the context of a given technical discipline, and (3) assigning a technical report that addresses a variety of readers, thus establishing the complexity of audience oriented writing.

  13. Elucidating the mechanisms of nickel compound uptake: A review of particulate and nano-nickel endocytosis and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Muñoz, Alexandra; Costa, Max, E-mail:


    Nickel (Ni) is a worldwide pollutant and contaminant that humans are exposed to through various avenues resulting in multiple toxic responses — most alarming is its clear carcinogenic nature. A variety of particulate Ni compounds persist in the environment and can be distinguished by characteristics such as solubility, structure, and surface charge. These characteristics influence cellular uptake and toxicity. Some particulate forms of Ni are carcinogenic and are directly and rapidly endocytized by cells. A series of studies conducted in the 1980s observed this process, and we have reanalyzed the results of these studies to help elucidate the molecular mechanism of particulate Ni uptake. Originally the process of uptake observed was described as phagocytosis, however in the context of recent research we hypothesize that the process is macropinocytosis and/or clathrin mediated endocytosis. Primary considerations in determining the route of uptake here include calcium dependence, particle size, and inhibition through temperature and pharmacological approaches. Particle characteristics that influenced uptake include size, charge, surface characteristics, and structure. This discussion is relevant in the context of nanoparticle studies and the emerging interest in nano-nickel (nano-Ni), where toxicity assessments require a clear understanding of the parameters of particulate uptake and where establishment of such parameters is often obscured through inconsistencies across experimental systems. In this regard, this review aims to carefully document one system (particulate nickel compound uptake) and characterize its properties.

  14. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides (United States)

    Nowell, Lisa H.; Norman, Julia E.; Ingersoll, Christopher G.; Moran, Patrick W.


    /chemical characteristics of sediment, and uncertainty in TEB values. Additional evaluations of benchmarks in relation to sediment chemistry and toxicity are ongoing.

  15. The Influence of Professional Development on Teachers' Implementation of the Teaching Personal and Social Responsibility Model (United States)

    Lee, Okseon; Choi, Euichang


    The purpose of this study was to examine the influence of a professional development (PD) program on teachers' implementation of the Teaching Personal and Social Responsibility (TPSR) model, and to identify the characteristics of PD that influence teaching practice. The participants were six elementary school teachers and 12 students, and the data…

  16. Toxicities of sediments below 10 effluent outfalls to near-coastal areas of the Gulf of Mexico

    International Nuclear Information System (INIS)

    Lewis, M.; Weber, D.; Stanley, R.


    The chemical quality and toxicities of sediments collected in the receiving waters below 10 wastewater outfalls to Northwest Florida coastal areas were evaluated at multiple stations during 1994--1996. Eight types of toxicity tests using 11 test species were used to assess acute and chronic toxicity of the sediments collected below industrial, municipal, power generation and pulp mill outfalls. The primary objectives of the study were to evaluate the relative ability of different assessment procedures to detect toxicity and to provide some much-needed perspective on the impact of major point sources on sediment quality in Gulf of Mexico estuaries. The major chemical contaminants were heavy metals and PAHs. Acute and chronic toxicities were noted. Results of tests with sediment collected at the same location but several months later often differed. The most sensitive species were mysids and an estuarine amphipod. The least sensitive species were fish and macrophyte seedlings. There was poor correlation of effluent toxicity to sediment toxicity in the receiving water. Toxicity of the effluents was greater than that of the sediments. Overall, the unavailability of relevant chronic toxicity methods, uncertain criteria for choice of control stations, lack of guidance on frequency of testing and the dynamic physical and chemical characteristics of sediments are factors that need consideration if sediment monitoring is to be part of the NPDES regulatory process

  17. Teaching English Grammar Through Communicative Language Teaching Approach

    Institute of Scientific and Technical Information of China (English)



    Grammar is an important part of language learning. In order for students to have a functional knowledge of a language (in other words, that they can spontaneously produce language) they must have at least some knowledge about the grammatical con⁃structs of the language in question. How grammar can be taught? Considering various second language teaching methods, teaching grammar through Communicative Language Teaching Approach is the most talked. Emphasis in this article is put on the applica⁃tion of Communicative Language Teaching Approach in grammar teaching in college English classes.

  18. Estimation of toxicity using the Toxicity Estimation Software Tool (TEST) (United States)

    Tens of thousands of chemicals are currently in commerce, and hundreds more are introduced every year. Since experimental measurements of toxicity are extremely time consuming and expensive, it is imperative that alternative methods to estimate toxicity are developed.

  19. Exploiting Hypertext’s Potential for Teaching Gender Studies

    Directory of Open Access Journals (Sweden)

    Maya Zalbidea Paniagua


    Full Text Available The aim of this article is to show what feminist electronic literature can contribute to the study of gender theories and feminist literature. The study of feminist hypertext fictions and the use of hypertext as a teaching tool are facilitated by the intrinsic characteristics of the electronic medium, complementing the electronic medium and providing alternative possibilities in the learning process: collaborative authorship, multivocality, textual openness, non-hierarchical and rhizomatic structures, neo-kathartic effects and open publishing. Teaching feminist electronic literature using the hypertext offers the possibility of updating and discussing gender through a medium that permits rearranging the hypertext, better organized analyses of intertextuality and fostering the study through association and connections, which is the way the human brain works. The teaching method proposed pursues the objective of studying narratives about gender taking advantage of the new technologies without losing dialogues in class as intuitive learning process.

  20. Ideology Spotting: An Exercise in Teaching Conservatism and Liberalism (United States)

    Plazek, David J.


    It has long been lamented that Americans do not comprehend conservative and liberal ideologies and the associated policy preferences for each perspective (and the reasoning behind the associations). This research seeks to contribute to the teaching of conservatism and liberalism by creating a heuristic outlining six general characteristics for…

  1. From Classroom Teaching to Remote Teaching

    DEFF Research Database (Denmark)

    Borch, Ole; Helbo, Jan; Knudsen, Morten


    for teaching purpose on the Internet. It is also described how courses in the two different teaching environments can be maintained in one place. More professional teaching tools are available on the market, but the methods described in this paper are based on Luvit[1], an open low-cost web-based teaching tool...... and at the same time easy to learn and use by both developer and students. Two in-house project groups have tested the project work with success after a short learning period. 35 remote students under Open Education in Multimedia Industrial Information Technology (MII) are using the Luvit[1] tool and the methods...

  2. In which regions is breast-feeding safer from the impact of toxic elements from the environment?


    Cinar, Nursan; Ozdemir, Sami; Yucel, Oya; Ucar, Fatma


    Owing to its unique nutritional and immunological characteristics, breast milk is the most important food source for infants. But, children are at greater risk for exposure to environmental toxicants from breast milk. The aim of this study was to evaluate the influence of environmental pollution on essential and toxic element contents of breast milk and determine the risky locations in our population. This study was conducted on women who were breastfeeding (n=90). Milk samples were collected...

  3. Children's Ability to Recognise Toxic and Non-Toxic Fruits (United States)

    Fancovicova, Jana; Prokop, Pavol


    Children's ability to identify common plants is a necessary prerequisite for learning botany. However, recent work has shown that children lack positive attitudes toward plants and are unable to identify them. We examined children's (aged 10-17) ability to discriminate between common toxic and non-toxic plants and their mature fruits presented in…

  4. Toxic substances handbook (United States)

    Junod, T. L.


    Handbook, published in conjunction with Toxic Substances Alert Program at NASA Lewis Research Center, profiles 187 toxic chemicals in their relatively pure states and include 27 known or suspected carcinogens.

  5. Toxicity evaluation and prediction of toxic chemicals on activated sludge system. (United States)

    Cai, Bijing; Xie, Li; Yang, Dianhai; Arcangeli, Jean-Pierre


    The gaps of data for evaluating toxicity of new or overloaded organic chemicals on activated sludge system resulted in the requirements for methodology of toxicity estimation. In this study, 24 aromatic chemicals typically existed in the industrial wastewater were selected and classified into three groups of benzenes, phenols and anilines. Their toxicity on activated sludge was then investigated. Two indexes of IC(50-M) and IC(50-S) were determined respectively from the respiration rates of activated sludge with different toxicant concentration at mid-term (24h) and short-term (30min) time intervals. Experimental results showed that the group of benzenes was the most toxic, followed by the groups of phenols and anilines. The values of IC(50-M) of the tested chemicals were higher than those of IC(50-S). In addition, quantitative structure-activity relationships (QSARs) models developed from IC(50-M) were more stable and accurate than those of IC(50-S). The multiple linear models based on molecular descriptors and K(ow) presented better reliability than single linear models based on K(ow). Among these molecular descriptors, E(lumo) was the most important impact factor for evaluation of mid-term toxicity. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  6. Using spaced education to teach interns about teaching skills. (United States)

    Pernar, Luise I M; Corso, Katherine; Lipsitz, Stuart R; Breen, Elizabeth


    Despite limited preparation and knowledge base, surgical interns have important teaching responsibilities. Nevertheless, few faculty development programs are aimed at interns. Succinct teaching skill content was electronically distributed over time (spaced education) to interns in academic year 2010/2011. The interns in the previous year served as historic controls. Electronic surveys were distributed for program evaluation. Fifteen of 24 (62.5%) interns and 35 of 49 (71.4%) students responded to the surveys in academic year 2009/2010 and 16 of 27 (59.3%) interns and 38 of 52 (73%) students responded in academic year 2010/2011. Surveys showed improved attitudes toward teaching by interns as well as a higher estimation of interns' teaching skills as rated by students for those interns who received the spaced education program. Using spaced education to improve interns' teaching skills is a potentially powerful intervention that improves interns' enthusiasm for teaching and teaching effectiveness. The changes are mirrored in students' ratings of interns' teaching skills and interns' attitudes toward teaching. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Determination of leachate toxicity through acute toxicity using Daphnia pulex and anaerobic toxicity assays


    Carabalí-Rivera, Y. S; Barba-Ho, L. E; Torres-Lozada, P


    ABSTRACT The municipal solid waste (MSW) of large cities, in particular the ones of developing countries, is mainly disposed in landfills (LFs), whose inadequate management generates the emission of greenhouse gases and the production of leachates with high concentrations of organic and inorganic matter and, occasionally heavy metals. In this study, the toxicity of the leachates from an intermediate-age municipal landfill was evaluated by ecotoxicity and anaerobic toxicity tests. The acute to...

  8. A teaching-learning sequence about weather map reading (United States)

    Mandrikas, Achilleas; Stavrou, Dimitrios; Skordoulis, Constantine


    In this paper a teaching-learning sequence (TLS) introducing pre-service elementary teachers (PET) to weather map reading, with emphasis on wind assignment, is presented. The TLS includes activities about recognition of wind symbols, assignment of wind direction and wind speed on a weather map and identification of wind characteristics in a weather forecast. Sixty PET capabilities and difficulties in understanding weather maps were investigated, using inquiry-based learning activities. The results show that most PET became more capable of reading weather maps and assigning wind direction and speed on them. Our results also show that PET could be guided to understand meteorology concepts useful in everyday life and in teaching their future students.

  9. Mdr1a plays a crucial role in regulating the analgesic effect and toxicity of aconitine by altering its pharmacokinetic characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Lijun; Wu, Jinjun; Zhao, Min; Song, Wenjie; Qi, Xiaoxiao; Wang, Ying [International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006 (China); Lu, Linlin [International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006 (China); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (SAR) 999078 (China); Liu, Zhongqiu, E-mail: [International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006 (China); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (SAR) 999078 (China)


    Aconitine (AC) is the primary bioactive/toxic alkaloid in plants of the Aconitum species. Our previous study demonstrated that Mdr1 was involved in efflux of AC. However, the mechanism by which Mdr1 regulates the efficacy/toxicity of AC in vivo remains unclear. The present study aimed to determine the effects of Mdr1a on the efficacy/toxicity and pharmacokinetics of AC in wild-type and Mdr1a{sup −/−} FVB mice. After oral administration of AC, significantly higher analgesic effect was observed in Mdr1a{sup −/−} mice (49% to 105%) compared to wild-type mice (P < 0.05). The levels of s100-β protein and creatine kinase, which indicate cerebral and myocardial damage, respectively, were also significantly increased (P < 0.05) in Mdr1a{sup −/−} mice. Histopathological examination revealed that the Mdr1a{sup −/−} mice suffered from evident cerebral and myocardial damages, but the wild-type mice did not. These findings suggested that Mdr1a deficiency significantly promoted the analgesic effect of AC and exacerbated its toxicity. Pharmacokinetic experiments showed that T{sub 1/2} of AC in the Mdr1a{sup −/−} mice was significantly higher (from 87% to 300%) than that in wild-type mice (P < 0.05). The distribution of AC in the brain of Mdr1a{sup −/−} mice was 2- to 32-fold higher than that in the brains of wild-type mice (P < 0.05). Toxic reactions were more severe in Mdr1a{sup −/−} mice compared to wild-type mice. In conclusion, Mdr1a deficiency significantly enhanced the analgesic effect of AC and exacerbated its toxicity by upregulating its distribution to the brain and decreasing its plasma elimination rate. Thus, Mdr1a dysfunction may cause severe AC poisoning. - Highlights: • The efficacy and toxicity of aconitine were significantly enhanced in Mdr1a{sup −/−} mice. • The distribution of aconitine to the brain was remarkably increased in Mdr1a{sup −/−} mice. • The elimination rate of aconitine was significantly decreased in Mdr1a

  10. Toxic clinical hypoxic radiation sensitizers plus radiation-induced toxicity

    International Nuclear Information System (INIS)

    Richmond, R.C.


    The operational definition espoused twelve years ago that clinical hypoxic radiation sensitizers should be nontoxic interferes with the recognition and research of useful radiation sensitizers. Eight years ago the toxic antitumor drug cis-dichlorodiammineplatinum(II) was reported to be a hypoxic radiation sensitizer and the selective antitumor action of this drug was stressed as potentially creating tumor-targeted radiation sensitization. This rationale of oxidative antitumor drugs as toxic and targeted clinical sensitizers is useful, and has led to the study reported here. The antitumor drug cis-(1,1-cyclobutane-dicarboxylato)diammineplatinum(II), or JM-8, is being tested in clinical trials. Cells of S. typhimurium in PBS in the presence of 0.2mM JM-8 are found to be sensitized to irradiation under hypoxic, but not oxic, conditions. JM-8 is nontoxic to bacteria at this concentration, but upon irradiation the JM-8 solution becomes highly toxic. This radiation induced toxicity of JM-8 preferentially develops from hypoxic solution, and thus contributes to the rationale of hypoxic tumor cell destruction

  11. Reform and practice for photoelectric specialty experimental teaching based on virtual simulation experiment platform (United States)

    Ye, Yan; Lv, Qingsong; Wu, Maocheng; Xu, Yishen; Gu, Jihua


    In view of some problems about the traditional photoelectric specialty experimental teaching process, such as separation of theoretical teaching and practical teaching, immobilization of experimental teaching contents, low quality of experiments and no obvious effect, we explored and practiced a new experimental teaching model of "theoretical teaching, virtual simulation and physical experiment", which combined the characteristics of photoelectric information science and engineering major and the essential requirements of engineering innovation talents cultivation. The virtual simulation experiment platform has many advantages, such as high performance-to-price ratio, easy operation and open experimental process, which makes virtual simulation combine physical experiment, complete each other with virtual for practical. After the users log into the virtual simulation experimental platform, they will first study the contents of the experiment, clarify the purpose and requirements of the experiment, master the method of using the instrument and the relevant notes, and then use the experimental instruments provided by the platform to build the corresponding experimental system. Once the experimenter's optical path is set incorrectly or the instrument parameters are set incorrectly, the error or warning message will be automatically triggered, and the reference information will be given instructing the student to complete the correct experimental operation. The results of our practice in recent years show that the teaching reform of the photoelectric specialty experiments has not only brought great convenience to the experimental teaching management, broadened the students' thinking and vision, enhanced the students' experimental skills and comprehensive qualities, but also made the students participate in the experiment with their enthusiasm. During the construction of experiment programs, the students' engineering practical ability and independent innovation awareness

  12. Mobile internet and technology for optical teaching reform in higher education (United States)

    Zhou, Muchun; Zhao, Qi; Chen, Yanru


    There are some problems in optical education such as insufficient flexibility, individuality and adaptability to students who need information and education at present. The development of mobile internet and technology provides support to solve these problems. Basic characteristics, advantages and developments of these techniques used in education are presented in this paper. Mobile internet is introduced to reform the classroom teaching of optical courses. Mobile network tool selection, teaching resources construction and reform in teaching methods are discussed. Academic record and sampling surveys are used to assess intention to adopt mobile internet and learning effect of academic major of students, the results show that high quality optical education can be offered by adopting mobile internet and technologies in traditional instruction.

  13. An exploration for research-oriented teaching model in biology teaching. (United States)

    Xing, Wanjin; Mo, Morigen; Su, Huimin


    Training innovative talents, as one of the major aims for Chinese universities, needs to reform the traditional teaching methods. The research-oriented teaching method has been introduced and its connotation and significance for Chinese university teaching have been discussed for years. However, few practical teaching methods for routine class teaching were proposed. In this paper, a comprehensive and concrete research-oriented teaching model with contents of reference value and evaluation method for class teaching was proposed based on the current teacher-guiding teaching model in China. We proposed that the research-oriented teaching model should include at least seven aspects on: (1) telling the scientific history for the skills to find out scientific questions; (2) replaying the experiments for the skills to solve scientific problems; (3) analyzing experimental data for learning how to draw a conclusion; (4) designing virtual experiments for learning how to construct a proposal; (5) teaching the lesson as the detectives solve the crime for learning the logic in scientific exploration; (6) guiding students how to read and consult the relative references; (7) teaching students differently according to their aptitude and learning ability. In addition, we also discussed how to evaluate the effects of the research-oriented teaching model in examination.

  14. Toxicity assessment and geochemical model of chromium leaching from AOD slag. (United States)

    Liu, Bao; Li, Junguo; Zeng, Yanan; Wang, Ziming


    AOD (Argon Oxygen Decarburization) slag is a by-product of the stainless steel refining process. The leaching toxicity of chromium from AOD slag cannot be ignored in the recycling process of the AOD slag. To assess the leaching toxicity of the AOD slag, batch leaching tests have been performed. PHREEQC simulations combined with FactSage were carried out based on the detailed mineralogical analysis and petrophysical data. Moreover, Pourbaix diagram of the Cr-H2O system was protracted by HSC 5.0 software to explore the chromium speciation in leachates. It was found that AOD slag leachate is an alkaline and reductive solution. The Pourbaix diagram of the Cr-H2O system indicated that trivalent chromium, such as Cr(OH)4(-), is the major chromium species in the experimental Eh-pH region considered. However, toxic hexavalent chromium was released with maximum concentrations of 30 µg L(-1) and 18 µg L(-1) at L/S 10 and 100, respectively, during the earlier leaching stage. It concluded that the AOD slag possessed a certain leaching toxicity. After 10 d of leaching, trivalent chromium was the dominant species in the leachates, which corresponded to the results of PHREEQC simulation. Leaching toxicity of AOD slag is based on the chromium speciation and its transformation. Great attention should be focused on such factors as aging, crystal form of chromium-enriched minerals, and electrochemical characteristics of the leachates. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Good Teachers, Scholarly Teachers and Teachers Engaged in Scholarship of Teaching and Learning: A Case Study from McMaster University, Hamilton, Canada (United States)

    Vajoczki, Susan; Savage, Philip; Martin, Lynn; Borin, Paola; Kustra, Erika D. H.


    This paper defines and operationalizes definitions of good teaching, scholarly teaching and the scholarship of teaching and learning in order to measure characteristics of these definitions amongst undergraduate instructors at McMaster University. A total of 2496 instructors, including all part-time instructors, were surveyed in 2007. A total of…

  16. Development of an accelerated leaching method for incineration bottom ash correlated to toxicity characteristic leaching protocol. (United States)

    Lin, Shengxuan; Zhou, Xuedong; Ge, Liya; Ng, Sum Huan; Zhou, Xiaodong; Chang, Victor Wei-Chung


    Heavy metals and some metalloids are the most significant inorganic contaminants specified in toxicity characteristic leaching procedure (TCLP) in determining the safety of landfills or further utilization. As a consequence, a great deal of efforts had been made on the development of miniaturized analytical devices, such as Microchip Electrophoresis (ME) and μTAS for on-site testing of heavy metals and metalloids to prevent spreading of those pollutants or decrease the reutilization period of waste materials such as incineration bottom ash. However, the bottleneck lied in the long and tedious conventional TCLP that requires 18 h of leaching. Without accelerating the TCLP process, the on-site testing of the waste material leachates was impossible. In this study, therefore, a new accelerated leaching method (ALM) combining ultrasonic assisted leaching with tumbling was developed to reduce the total leaching time from 18 h to 30 min. After leaching, the concentrations of heavy metals and metalloids were determined with ICP-MS or ICP-optical emission spectroscopy. No statistical significance between ALM and TCLP was observed for most heavy metals (i.e., cobalt, manganese, mercury, molybdenum, nickel, silver, strontium, and tin) and metalloids (i.e., arsenic and selenium). For the heavy metals with statistical significance, correlation factors derived between ALM and TCLP were 0.56, 0.20, 0.037, and 0.019 for barium, cadmium, chromium, and lead, respectively. Combined with appropriate analytical techniques (e.g., ME), the ALM can be applied to rapidly prepare the incineration bottom ash samples as well as other environmental samples for on-site determination of heavy metals and metalloids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. The hologram and its utilization as a physics teaching tool for physics teaching in engineering courses


    Toledo, Rolando Serra; Cruz, Gilda Vega; Zaldo, Angel Ferrat; Lunazzi, José J.; Magalhães, Daniel S.F.


    With the emergence and development of the white-light holograms, new possibilities were created for its utilization as a teaching tool due to the characteristic of producing a three-dimensional image which constitutes an optical duplicate of the object. In this work the distinctive aspects of the hologram are described and its utilization is analyzed in engineering courses, through the design and construction of a Didactic Exhibition of Holography. Con el surgimiento de los hologramas reco...

  18. Immunotoxicity, genotoxicity and epigenetic toxicity of nanomaterials: New strategies for toxicity testing? (United States)

    Dusinska, Maria; Tulinska, Jana; El Yamani, Naouale; Kuricova, Miroslava; Liskova, Aurelia; Rollerova, Eva; Rundén-Pran, Elise; Smolkova, Bozena


    The unique properties of nanomaterials (NMs) are beneficial in numerous industrial and medical applications. However, they could also induce unintended effects. Thus, a proper strategy for toxicity testing is essential in human hazard and risk assessment. Toxicity can be tested in vivo and in vitro; in compliance with the 3Rs, alternative strategies for in vitro testing should be further developed for NMs. Robust, standardized methods are of great importance in nanotoxicology, with comprehensive material characterization and uptake as an integral part of the testing strategy. Oxidative stress has been shown to be an underlying mechanism of possible toxicity of NMs, causing both immunotoxicity and genotoxicity. For testing NMs in vitro, a battery of tests should be performed on cells of human origin, either cell lines or primary cells, in conditions as close as possible to an in vivo situation. Novel toxicity pathways, particularly epigenetic modification, should be assessed along with conventional toxicity testing methods. However, to initiate epigenetic toxicity screens for NM exposure, there is a need to better understand their adverse effects on the epigenome, to identify robust and reproducible causal links between exposure, epigenetic changes and adverse phenotypic endpoints, and to develop improved assays to monitor epigenetic toxicity. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Radionuclide toxicity

    International Nuclear Information System (INIS)

    Galle, P.


    The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

  20. Application of case teaching in genetics courses to students majoring in forestry. (United States)

    Wang, Qin-Mei; Cui, Jian-Guo; Yu, Chang-Zhi; Zhang, Zhi; Wu, Yue-Liang; Zhang, Li-Jie; Lin, Mei


    Undergraduate students majoring in forestry generally reflect that genetics is one of the most difficult compul-sory courses, because the traditional teaching method is difficult to satisfy their needs. According to the theoretical charac-teristics of forestry and actual demands of the students, in the light of teaching and research experience in recent years, we adopted a series of typical genetic cases such as 'opening coffin to identify relatives', stem-throne of Lycium ruthenicum Murr, and magic powers in Harry Potter. Our practices revealed that the case teaching in genetics could train good personality traits, learning abilities and creativity of the students, stimulate their interests and initiatives in learning, and increase systematic learning.


    Directory of Open Access Journals (Sweden)

    Elaine Teixeira da Silva


    Full Text Available This article aims to describe the possibilities provided by the use of new digital Information and Communication Technologies (ICT, aided by Web 2.0, on Spanish teaching both inside and outside classroom. We analyzed the social network Facebook because it has a large number of users who spend a significant amount of time on the site chatting with friends, posting comments, liking photos and profiles and participating in groups. This social network also provides teaching tools that will help students to develop their autonomy to (re learn how to think. It is shown that Facebook presents EaD characteristics and therefore can be considered an additional tool on language teaching and education.

  2. How surgical mentors teach: a classification of in vivo teaching behaviors part 2: physical teaching guidance. (United States)

    Sutkin, Gary; Littleton, Eliza B; Kanter, Steven L


    To study surgical teaching captured on film and analyze it at a fine level of detail to categorize physical teaching behaviors. We describe live, filmed, intraoperative nonverbal exchanges between surgical attending physicians and their trainees (residents and fellows). From the films, we chose key teaching moments and transcribed participants' utterances, actions, and gestures. In follow-up interviews, attending physicians and trainees watched videos of their teaching case and answered open-ended questions about their teaching methods. Using a grounded theory approach, we examined the videos and interviews for what might be construed as a teaching behavior and refined the physical teaching categories through constant comparison. We filmed 5 cases in the operating suite of a university teaching hospital that provides gynecologic surgical care. We included 5 attending gynecologic surgeons, 3 fellows, and 5 residents for this study. More than 6 hours of film and 3 hours of interviews were transcribed, and more than 250 physical teaching motions were captured. Attending surgeons relied on actions and gestures, sometimes wordlessly, to achieve pedagogical and surgical goals simultaneously. Physical teaching included attending physician-initiated actions that required immediate corollary actions from the trainee, gestures to illustrate a step or indicate which instrument to be used next, supporting or retracting tissues, repositioning the trainee's instruments, and placement of the attending physicians' hands on the trainees' hands to guide them. Attending physicians often voiced surprise at the range of their own teaching behaviors captured on film. Interrater reliability was high using the Cohen κ, which was 0.76 for the physical categories. Physical guidance is essential in educating a surgical trainee, may be tacit, and is not always accompanied by speech. Awareness of teaching behaviors may encourage deliberate teaching and reflection on how to innovate pedagogy

  3. Toxicity of copper chelates of azomethines and amino acids for Chlorella pyrenoidosa

    Energy Technology Data Exchange (ETDEWEB)

    Barashkov, G.K.; Rukhadze, E.G.; Talyzenkova, G.P.


    The authors have attempted to assess the toxicity of copper-containing compounds from the point of view of their interrelationship with the structural characteristics of the chelate compound and the structure of the ligand. The copper chelates of the azomethines tested may be provisionally divided into three types: A - complexes with N-alkly-azomethines; B - complexes with N-aryl-azomethines; C - binuclear complexes. Consideration was also given to chelates with aromatic and heterocyclic amino acids and to heteroligand chelates in which the copper atom coordinates azomethine and an amino acid simultaneously. Toxicity was determined by the method previously described and expressed as a critical concentration (C/sub cr/, mg Cu/liter) and in relative toxicity units (T/sub c/). The compounds investigated were obtained from the interaction between a bidentant ligand of an azomethine or anamino acid and copper acetate in a water-alcohol medium at pH 6-8. Since they are not very soluble in water, true solutions were obtained by using dimethyl sulfoxide.

  4. Teaching skills and personal characteristics of sex education teachers

    NARCIS (Netherlands)

    Timmerman, Greetje; Timmerman, M.C.

    This article examines relationships between various dimensions of teachers' professionalism, that is, pedagogical content knowledge and personal characteristics. Using Shulman's notion of pedagogical content knowledge (PCK) we explored the practical knowledge of twenty sex education teachers using

  5. Optimization of organic contaminant and toxicity testing analytical procedures for estimating the characteristics and environmental significance of natural gas processing plant waste sludges

    International Nuclear Information System (INIS)

    Novak, N.


    The Gas Plant Sludge Characterization Phase IIB program is a continuation of the Canadian Petroleum Association's (CPA) initiatives to characterize sludge generated at gas processing plants. The objectives of the Phase IIB project were to develop an effective procedure for screening waste sludges or centrifuge/leachate generated from sludge samples for volatile, solvent-soluble and water-soluble organics; verify the reproducibility of the three aquatic toxicity tests recommended as the battery of tests for determining the environmental significance of sludge centrifugates or leachates; assess the performance of two terrestrial toxicity tests in determining the environmental significance of whole sludge samples applied to soil; and to assess and discuss the reproducibility and cost-effectiveness of the sampling and analytical techniques proposed for the overall sludge characterization procedure. Conclusions and recommendations are provided for sludge collection, preparation and distribution, organic analyses, toxicity testing, project management, and procedure standardization. The three aquatic and two terrestrial toxicity tests proved effective in indicating the toxicity of complex mixtures. 27 refs., 3 figs., 59 tabs

  6. Teaching Teachers to Play and Teach Games (United States)

    Wright, Steven; McNeill, Michael; Fry, Joan; Wang, John


    This study was designed to determine the extent to which a technical and a tactical approach to teaching a basketball unit to physical education teacher education (PETE) students would each affect their games playing abilities, perceived ability to teach, and approach preference for teaching the game. Pre- and post-unit data were collected through…

  7. Teaching Culture Perception: Documenting and Transforming Institutional Teaching Cultures (United States)

    Kustra, Erika; Doci, Florida; Gillard, Kaitlyn; Hondzel, Catharine Dishke; Goff, Lori; Gabay, Danielle; Meadows, Ken N.; Borin, Paola; Wolf, Peter; Ellis, Donna; Eiliat, Hoda; Grose, Jill; Dawson, Debra L.; Hughes, Sandy


    An institutional culture that values teaching is likely to lead to improved student learning. The main focus of this study was to determine faculty, graduate and undergraduate students' perception of the teaching culture at their institution and identify indicators of that teaching culture. Themes included support for teaching development; support…

  8. Effectiveness of simple control measures on methicillin-resistant Staphylococcus aureus infection status and characteristics with susceptibility patterns in a teaching hospital in Peshawar. (United States)

    Rafiq, Muhammad Salman; Rafiq, Muhammad Imran; Khan, Taimur; Rafiq, Maria; Khan, Mah Muneer


    To determine the effectiveness of simple control measures on the infection status and characteristics of methicillin-resistant Staphylococcus aureus including susceptibility patterns among health professionals and patients in a teaching hospital. The cross-sectional study was conducted from September 2013 to January 2014, and comprised samples collected from healthcare personnel and patients in the various units of Khyber Teaching Hospital, Peshawar. The specimens were collected before and one month after the implementation of simple control measures for outbreak prevention of methicillin-resistant Staphylococcus aureus. These were tested for culture and antimicrobial susceptibility. Data about methicillin-sensitive and methicillin-resistant Staphylococcus aureus infection, wound characteristics and susceptibility patterns was collected and effectiveness of simple control measures was determined. SPSS 20 was used for statistical analysis. Of the total 390 isolates, 180(46.2%) were Staphylococcus aureus; 77(19.7%) from healthcare personnel and 103(26.4%) from patients. Of these, 164(42.1%) were methicillin-sensitive and 16(4.1%) were methicillin-resistant. Among the patients, 38(15.1%) methicillin-sensitive and 8(3.2%) methicillin-resistant isolates were recovered from wounds or skin and soft tissues. Pus with 33(13.1%) and 4(1.6%) cases respectively was the second most common source. Among methicillin-resistant isolates, resistance to Linezolid was 0%, all were resistant to Oxacillin, Cefoxitin, Amoxicillin, Cefotaxime and Cephradine, and resistance to both Co-Amoxiclav and Ciprofloxacin was 87.5%. After one month of implementation of simple control measures, the number of methicillin-resistant cases among healthcare professionals and patients dropped from 4(2.9%) and 7(10.8%) to 1(0.7%) and 5(2.7%), respectively. Methicillin-resistant and methicillin-sensitive Staphylococcus aureus differed in their anti-microbial susceptibility profiles. Selection of antibiotics

  9. In vitro toxicity analysis of nanoscale aluminum: Particle size and shape effects (United States)

    Palazuelos Jorganes, Maria


    Nanostructured materials promise to revolutionize many key areas of science and technology. As our ability to manipulate matter at the nanoscale increases, there is a need to assess the effects of these materials on human health and the environment. Materials at the nanoscale are interesting and useful because they possess properties that are different from the equivalent bulk or molecular scale. These same properties can make toxicological profiles very different from those of the same materials on a different scale. There is a rising consensus that toxicity analysis of nanomaterials should start from a thorough physicochemical characterization of the materials under investigation in order to be able to establish a proper correlation between the nanoparticles characteristics and their effects and behavior in physiological environments. This research is a clear example of the necessity of comprehensive studies when investigating the toxicity of nanomaterials. Aluminum nanoparticles are being extensively used for their very unique energetic properties. These materials offer a very promising market that is fostering many startup companies which are expected to consolidate on strong technological positions. Aluminum is generally recognized as a non-toxic material to humans and it is widely used for applications which imply direct human contact. The effect of aluminum nanoparticles in human health is still an unknown. My research consisted of an in vitro toxicity screening of aluminum materials from nano to micron size, including spherical irregularly shaped particles. Several issues relating to size, shape, detection and characterization of nanoparticles in the different environments relevant to in vitro toxicity analysis were addressed and suitable protocols were developed. Lung human epithelial cells were exposed to different concentrations of these materials and the effects were analyzed by means of various toxicity tests. Some of the materials investigated caused

  10. Electronic Cigarette Toxicity. (United States)

    Payne, J Drew; Michaels, David; Orellana-Barrios, Menfil; Nugent, Kenneth


    Electronic cigarettes (e-cigarettes) are often advertised as a healthier product when compared with traditional cigarettes. Currently, there are limited data to support this and only a threat of federal regulation from the US Food and Drug Administration. Calls to poison control centers about e-cigarette toxicity, especially in children, and case reports of toxic exposures have increased over the past 3 years. This research letter reports the frequency of hazardous exposures to e-cigarettes and characterizes the reported adverse health effects associated with e-cigarette toxicity.

  11. Evaluation of nano-specific toxicity of zinc oxide, copper oxide, and silver nanoparticles through toxic ratio

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weicheng; Liu, Xiawei; Bao, Shaopan; Xiao, Bangding; Fang, Tao, E-mail: [Chinese Academy of Sciences, Institute of Hydrobiology (China)


    For safety and environmental risk assessments of nanomaterials (NMs) and to provide essential toxicity data, nano-specific toxicities, or excess toxicities, of ZnO, CuO, and Ag nanoparticles (NPs) (20, 20, and 30 nm, respectively) to Escherichia coli and Saccharomyces cerevisiae in short-term (6 h) and long-term (48 h) bioassays were quantified based on a toxic ratio. ZnO NPs exhibited no nano-specific toxicities, reflecting similar toxicities as ZnO bulk particles (BPs) (as well as zinc salt). However, CuO and Ag NPs yielded distinctly nano-specific toxicities when compared with their BPs. According to their nano-specific toxicities, the capability of these NPs in eliciting hazardous effects on humans and the environment was as follows: CuO > Ag > ZnO NPs. Moreover, long-term bioassays were more sensitive to nano-specific toxicity than short-term bioassays. Overall, nano-specific toxicity is a meaningful measurement to evaluate the environmental risk of NPs. The log T{sub e}{sup particle} value is a useful parameter for quantifying NP nano-specific toxicity and enabling comparisons of international toxicological data. Furthermore, this value could be used to determine the environmental risk of NPs.

  12. Using Realia to Teach Physically Disabled Students in Writing Descriptive Texts

    Directory of Open Access Journals (Sweden)

    Noorma Fitriana M. Zain


    Full Text Available This case study is focused on teaching descriptive texts by using realia. The writer took the 8th grade students of SMPLB Negeri Ungaran as the subjects of the study. The aim of this research is to know the implementation of teaching descriptive texts that cover parts, qualities, and characteristics of the objects. This study was carried out around four meetings. In each meeting, the researcher observed the situation of the class and the setudents’ activities in that classroom. The data collection method used in the research was observation, interview, and documentation. In implementating the research, the researcher found several problems and difficulties in teaching learning processes. One of them is that, the teaching physically disabled students are not easy. It has to be slowly because the students’ ability in writing the lesson is limited. The other problem comes from the teacher him/herself that never uses media or tools to teach physically disabled students. It is a matter of fact that teaching physically  disabled students needs media to make them easily understand the learning materials. One of the media that could be used is realia. From this research it is expected that the problems could be solved and a new paradigm in teaching descriptive texts for disabled students could be considered.

  13. Maternal characteristics and timing of presentation following pre ...

    African Journals Online (AJOL)

    Background: To examine the influence of maternal characteristics on timing of presentation for intervention following pre-labour rupture of membrane (PROM) at term. Materials and Methods: This was a descriptive study of cases of term PROM with singleton births at the University of Benin Teaching Hospital (UBTH) from ...

  14. Growth performance, carcass and organ characteristics of growing ...

    African Journals Online (AJOL)

    An experiment was conducted at the Department of Animal Science teaching and research farm, Bayero University Kano, to evaluate the effect of feeding graded levels of Moringa oleifera leaf meal (MOLM) in diets on growth performance, carcass and organ characteristics of weaned rabbits. Twenty eight grower rabbits of ...

  15. Maternal mortality and delay: Socio-demographic characteristics of ...

    African Journals Online (AJOL)

    This study assessed the contribution of delay to maternal deaths and also determined the socio¬demographic characteristics of patients with maternal deaths with associated delay. Methods: This is a cross-sectional descriptive study of all maternal deaths in Irrua specialist Teaching Hospital, Nigeria between January 1999 ...

  16. On Teaching History in the Prisons of Georgia: A Person View. (United States)

    Durand, Robert


    Teaches a history course in a correctional facility in Georgia. Discusses class problems, testing, grading procedures, and the environment. Finds establishing routine is effective in bringing order and purpose to the class. Describes student characteristics and response to the class. (NL)

  17. Pulmonary toxicity of manufactured nanoparticles (United States)

    Peebles, Brian Christopher

    for occupational health. Permissible exposure limits to micrometer-size particulate matter in the workplace are in place, but current limits do not specifically address the role of surface chemistry and the potentially higher toxicity of nanomaterials. The size, agglomeration characteristics, and surface chemistry of carbon nanoparticles are being studied and manipulated to explore the causes of their toxicity. Inflammatory response and cytotoxicity following exposure of human and murine macrophages to nanoparticles are being employed as indicators of the ability of particles to cause respiratory harm. The results are expected to lead to more effective standards for nanomaterial exposure in the workplace and pathways to toxicity mitigation.

  18. What motivates residents to teach? The Attitudes in Clinical Teaching study. (United States)

    Dotters-Katz, Sarah; Hargett, Charles W; Zaas, Aimee K; Criscione-Schreiber, Lisa G


    Graduate medical trainees have a critical role in the teaching of other trainees. Improving their teaching requires an understanding of their attitudes towards teaching and their motivation to teach. Both have been incompletely explored in this population. We aimed to better understand graduate medical trainees' attitudes towards teaching and motivation to teach in the clinical setting in order to inform modifications to resident-as-teacher (RAT) programmes and enhance teaching practices. We applied Q methodology, an established sorting method, to identify and quantify the factors that have an impact on trainees' engagement in teaching. We invited house officers at our institution to rank-order 47 statements regarding their attitudes to and motivation for teaching. Respondents explained their Q-sort rankings in writing and completed a demographic questionnaire. By-person factor analysis yielded groups of individuals with similar attitudes. One hundred and seven trainees completed the Q-sort. We found three primary groups of attitudes towards teaching in the clinical setting: enthusiasm, reluctance and rewarded. Enthusiastic teachers are committed and make time to teach. Teaching increases their job satisfaction. Reluctant teachers have enthusiasm but are earlier in training and feel limited by clinical workload and unprepared. Rewarded teachers feel teaching is worthwhile and derive satisfaction from the rewards and recognition they receive for teaching. This improved understanding of common attitudes shared by groups of residents will help curriculum designers create RAT programmes to further reinforce and encourage attitudes that promote teaching as well as improve trainees' motivation to teach. Designing RAT programmes that acknowledge the attitudes to and motivations for teaching should help develop effective teachers to improve educational outcomes. Directed efforts to enhance motivation for reluctant teachers and encourage more positive attitudes in rewarded

  19. Cyclophosphamide-induced pulmonary toxicity

    International Nuclear Information System (INIS)

    Siemann, D.W.; Macler, L.; Penney, D.P.


    Unlike radiation effects, pulmonary toxicity following drug treatments may develop soon after exposure. The dose-response relationship between Cyclophosphamide and lung toxicity was investigated using increased breathing frequency assays used successfully for radiation induced injury. The data indicate that release of protein into the alveolus may play a significant role in Cy induced pulmonary toxicity. Although the mechanism responsible for the increased alveolar protein is as yet not identified, the present findings suggest that therapeutic intervention to inhibit protein release may be an approach to protect the lungs from toxic effects. (UK)



    Bektas, Meral; Erkal, Pinar


    In toxic organizations which are mostly destructive instead of being constrictive towards its employees, toxicity behaviors emerge as a result of the formal and informal relationships. Toxicity behaviors are often negatively affect motivation, job satisfaction or performance of the employees in workplace. Basic toxicity behaviors in organizations are: extreme jealousy, biting words, emphasis  superiority emphasis, getting angry, offending employees, strict control, heavy job workload, limited...

  1. Antimony Toxicity


    Sundar, Shyam; Chakravarty, Jaya


    Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans. Improvements in working conditions have remarkably decreased the incidence of antimony toxicity in the workplace. As a therapeutic, antimony has been mostly used for the treatment of leishmaniasis and schistosomiasis. The...

  2. Nursing Students’ Perceptions on Characteristics of an Effective Clinical Instructor

    Directory of Open Access Journals (Sweden)

    Joan E. Niederriter PhD, MSN, CMSRN, RN-BC


    Full Text Available Purpose To identify characteristics and teaching techniques of effective clinical instructors that can be utilized or implemented to improve the student nurse clinical experience. Background The clinical instructor is an integral part of a quality clinical experience. They help students transfer didactic information to the practice setting. The clinical nursing experience is a vital component in the developmental process of the nursing student. Research has been done on this subject, but gaps remain. The need for a more in-depth understanding of students’ perceptions of the characteristics and teaching techniques that best aid their comprehension and learning will help instructors to maximize student learning experiences in the practice setting. Method This qualitative research study utilized the phenomenological research method. Three open-ended questions were posed to 14 nursing students to identify the characteristics and teaching techniques they believed comprised an effective clinical instructor. Individual interviews were conducted and transcribed interviews were reviewed to identify common themes. Three faculty members provided member checking to prevent bias by reviewing the transcribed interviews for common themes. Findings Participants identified four main themes which include a trusting relationship, experience or knowledge, coach, and role model. The students found that they gained more knowledge, developed more critical thinking, and felt more confident with instructors who utilized characteristics and techniques from these four areas. Conclusion Clinical instructors play an important role in preparing the student nurse in becoming a competent nurse in the practice setting. This information can be used to provide a foundation in creating an educational opportunity to inform nurse educators in the ways to become a more effective clinical instructor.

  3. Good Mathematics Teaching from Mexican High School Students' Perspective (United States)

    Martinez-Sierra, Gustavo


    This paper reports a qualitative research that identifies the characteristics of good mathematics teaching from the perspective of Mexican high school students. For this purpose, the social representations of a good mathematics teacher and a good mathematics class were identified in a group of 67 students. In order to obtain information, a…

  4. Speechant: A Vowel Notation System to Teach English Pronunciation (United States)

    dos Reis, Jorge; Hazan, Valerie


    This paper introduces a new vowel notation system aimed at aiding the teaching of English pronunciation. This notation system, designed as an enhancement to orthographic text, was designed to use concepts borrowed from the representation of musical notes and is also linked to the acoustic characteristics of vowel sounds. Vowel timbre is…

  5. Content Maps: A Teaching and Assessment Tool for Content Knowledge (United States)

    Ward, Phillip; Lehwald, Harry; Lee, Yun Soo


    Developing content knowledge in teachers presents a constant challenge for teacher educators. This article introduces a teaching and assessment tool called a "content map," which allows teacher educators, teachers, and coaches to conceptualize the scope, sequence, and relational characteristics of the content being taught. Content maps…

  6. Rectal toxicity profile after transperineal interstitial permanent prostate brachytherapy: Use of a comprehensive toxicity scoring system and identification of rectal dosimetric toxicity predictors

    International Nuclear Information System (INIS)

    Shah, Jinesh N.; Ennis, Ronald D.


    Purpose: To better understand rectal toxicity after prostate brachytherapy, we employed the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE version 3.0), a comprehensive system with distinct and separately reported gastrointestinal adverse event items (unlike Radiation Therapy Oncology Group morbidity scoring), to evaluate item-specific postimplant rectal toxicities. Methods and Materials: We analyzed 135 patients treated with brachytherapy ± hormonal therapy, using CTCAE v3.0 to score acute/late rectal toxicities (median follow-up, 41 months). Dosimetric parameters were evaluated for ability to predict toxicities. Results: Use of CTCAE yielded a novel rectal toxicity profile consisting of diarrhea, incontinence, urgency, proctitis, pain, spasms, and hemorrhage event rates. No item had a 25 (percent of rectal volume receiving 25% of prescribed prostate dose) ≤ 25% vs. 60% for %V 25 > 25% (p 1 ≤ 40% vs. 44% for %V 1 > 40% (p = 0.007). Conclusions: A comprehensive understanding of item-specific postimplant rectal toxicities was obtained using CTCAE. Rectal %V 25 > 25% and %V 1 > 40% predicted worse late diarrhea and maximum toxicity, respectively

  7. A New In Vivo Model System to Assess the Toxicity of Semiconductor Nanocrystals

    Directory of Open Access Journals (Sweden)

    Angela Tino


    Full Text Available In the emerging area of nanotechnology, a key issue is related to the potential impacts of the novel nanomaterials on the environment and human health, so that this technology can be used with minimal risk. Specifically designed to combine on a single structure multipurpose tags and properties, smart nanomaterials need a comprehensive characterization of both chemicophysical properties and adequate toxicological evaluation, which is a challenging endeavour; the in vitro toxicity assays that are often employed for nanotoxicity assessments do not accurately predict in vivo response. To overcome these limitations and to evaluate toxicity characteristics of cadmium telluride quantum dots in relation to surface coatings, we have employed the freshwater polyp Hydra vulgaris as a model system. We assessed in vivo acute and sublethal toxicity by scoring for alteration of morphological traits, population growth rates, and influence on the regenerative capabilities providing new investigation clues for nanotoxicology purposes.

  8. Trichothecenes: structure-toxic activity relationships. (United States)

    Wu, Qinghua; Dohnal, Vlastimil; Kuca, Kamil; Yuan, Zonghui


    Trichothecenes comprise a large family of structurally related toxins mainly produced by fungi belonging to the genus Fusarium. Among trichothecenes, type A and type B are of the most concern due to their broad and highly toxic nature. In order to address structure-activity relationships (SAR) of trichothecenes, relationships between structural features and biological effects of trichothecene mycotoxins in mammalian systems are summarized in this paper. The double bond between C-9-C-10 and the 12,13-epoxide ring are essential structural features for trichothecene toxicity. Removal of these groups results in a complete loss of toxicity. A hydroxyl group at C-3 enhances trichothecene toxicity, while this activity decreases gradually when C-3 is substituted with either hydrogen or an acetoxy group. The presence of a hydroxyl group at C-4 promotes slightly lower toxicity than an acetoxy group at the same position. The toxicity for type B trichothecenes decreases if the substituent at C-4 is changed from acetoxy to hydroxyl or hydrogen at C-4 position. The presence of hydroxyl and hydrogen groups on C-15 decreases the trichothecene toxicity in comparison with an acetoxy group attached to this carbon. Trichothecenes toxicity increases when a macrocyclic ring exists between the C-4 and C-15. At C-8 position, an oxygenated substitution at C-8 is essential for trichothecene toxicity, indicating a decrease in the toxicity if substituent change from isovaleryloxy through hydrogen to the hydroxyl group. The presence of a second epoxy ring at C-7-C-8 reduces the toxicity, whereas epoxidation at C-9-C-10 of some macrocyclic trichothecenes increases the activity. Conjugated trichothecenes could release their toxic precursors after hydrolysis in animals, and present an additional potential risk. The SAR study of trichothecenes should provide some crucial information for a better understanding of trichothecene chemical and biological properties in food contamination.

  9. pH modulates arsenic toxicity in Bacillus licheniformis DAS-2. (United States)

    Tripti, K; Shardendu


    The toxic characteristics of arsenic species, As(V) and As(III) result in ecological risks. Arsenic tolerant bacterium was isolated and identified as the Bacillus licheniformis DAS-2 through 16SrDNA sequencing. B. licheniformis DAS-2 was efficient to tolerate and remove both the As(V)[MIC 8mM] and As(III)[MIC 6mM] from the growth medium. The potential for the removal/uptake of arsenic from the 3, 5 and 7mM As(V) enriched growth media was 100%, 60% and 35% respectively and from the 1, 3 and 5mM As(III) enrichment it was 100%, 99% and 58% respectively at neutral pH. 80% of uptake As(V) was reduced to As(III) in 3mM As(V) enrichment which was gradually decreased to only 17% at 7mM As(V) enrichment at neutral pH. The arsenic toxicity in B. licheniformis DAS-2 was found modulated by pH and was examined through alteration in growth, uptake/removal, reduction and measurement of chemical toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Joint use of laboratory bioassays and field-collected invertebrates to evaluate toxicity and contaminant bioaccumulation

    International Nuclear Information System (INIS)

    Long, S.P.; Byron, E.R.; Ohlendorf, H.M.


    Soil toxicity tests using earthworms (Eisenia andrei) were conducted using soil samples collected as part of ecological risk assessments for several sites at two facilities in California. At some sites, earthworms or other terrestrial invertebrates were collected in the field for chemical analysis. Ecological concerns focused on exposures to soil invertebrates and their secondary consumers, such as birds and small mammals. The toxicity tests were used to assess potential exposures to a variety of site-specific contaminants including organochlorine pesticides, PCBs, PAHs, petroleum hydrocarbons, heavy metals, and other inorganic substances. Site soils were combined with clean control soils to produce toxicity test soil dilutions containing 100%, 75%, 50%, 25%, and 0% site soils. Earthworm mortality and other observations were made at day 0, 7, 14, 21 and 28. Toxicity test results were combined with soil chemical analytical results and physical characteristics to establish NOAELs and LOAELs. Bioaccumulation in the laboratory earthworms and field-collected invertebrates was evaluated by comparing whole-body contaminant to soil contaminant concentrations. Allometric equations and sublethal toxicity data were used to predict potential effects on birds and small mammals. Earthworm toxicity tests indicated a wide range of sensitivity to on-site contaminants and showed the importance of considering potential confounding influences due to soil parameters other than contaminant concentration

  11. The Complementary Teaching of Physics and Music Acoustics - The Science of Sound (United States)

    Milicevic, D.; Markusev, D.; Nesic, Lj.; Djordjevic, G.


    The results of some up-to-date solutions referring to teaching physics as a part of educational reform in Serbia, can be negative in a great deal to content and scope of teaching process which has existed so far. Basic course and characteristics of those solutions mean decreasing the number of classes of full-time physics teaching. Such tendencies are unjustified for many reasons, and the basic one is that physics is the foundation of understanding not only natural science, but also art and music (optics and acoustics respectively) and physical education (statics and dynamics). As a result of all this, there is necessity to have natural lessons of physics with the teachers of subjects such as music, art and physical education. The main objective of it is to conclude one good quality teaching cycle, and make student acquire new as well as revise their knowledge in different subjects.

  12. Assessing the toxic effects of ethylene glycol ethers using Quantitative Structure Toxicity Relationship models

    International Nuclear Information System (INIS)

    Ruiz, Patricia; Mumtaz, Moiz; Gombar, Vijay


    Experimental determination of toxicity profiles consumes a great deal of time, money, and other resources. Consequently, businesses, societies, and regulators strive for reliable alternatives such as Quantitative Structure Toxicity Relationship (QSTR) models to fill gaps in toxicity profiles of compounds of concern to human health. The use of glycol ethers and their health effects have recently attracted the attention of international organizations such as the World Health Organization (WHO). The board members of Concise International Chemical Assessment Documents (CICAD) recently identified inadequate testing as well as gaps in toxicity profiles of ethylene glycol mono-n-alkyl ethers (EGEs). The CICAD board requested the ATSDR Computational Toxicology and Methods Development Laboratory to conduct QSTR assessments of certain specific toxicity endpoints for these chemicals. In order to evaluate the potential health effects of EGEs, CICAD proposed a critical QSTR analysis of the mutagenicity, carcinogenicity, and developmental effects of EGEs and other selected chemicals. We report here results of the application of QSTRs to assess rodent carcinogenicity, mutagenicity, and developmental toxicity of four EGEs: 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol and their metabolites. Neither mutagenicity nor carcinogenicity is indicated for the parent compounds, but these compounds are predicted to be developmental toxicants. The predicted toxicity effects were subjected to reverse QSTR (rQSTR) analysis to identify structural attributes that may be the main drivers of the developmental toxicity potential of these compounds.

  13. Degradation characteristics of urea and lime treated groundnut ...

    African Journals Online (AJOL)

    This research was conducted to investigate the chemical composition and rumen degradation characteristics of treated groundnut shells (GNS) based diets in the rumen. It was carried out in the Teaching and Research farm of the Department of Animal Science A.B.U. Zaria. Three fistulated Yankasa rams with average ...

  14. Teaching-learning of psychology: reflections from interbehavioral scientific matrix

    Directory of Open Access Journals (Sweden)

    Winter Edgar Reyna Cruz


    Full Text Available In previous works it has been pointed out that the exercise of Psychology is not limited to a single type of practice; On the contrary, psychologists perform philosophical, theoretical, technological, professional and transdisciplinary practices. Derived from the above in the present work, it is argued that teaching-learning Psychology demands that the aforementioned practices be taught-learn, to a greater or lesser extent. Based on this, (a the specific characteristics of each practice are described roughly; (b there is an aroused presentation of the main interbehavioral theoretical contributions regarding the teaching-learning of Psychology, the didactic interaction and the teacher's performance, which have focused on the learning of the practice of scientific investigation and its teaching; and, derived from the previous points, (c some reflections are presented regarding the teaching practice of psychology, as well as the learning of it, taking into account the different practices that are carried out in this discipline and not only with respect to the research practice. In the final comments, the benefits of the distinction of psychological practices in the training of apprentices of the discipline are indicated

  15. Oxygen toxicity

    Directory of Open Access Journals (Sweden)

    C. A. van der Westhuizen


    Full Text Available Oxygen has been discovered about 200 years ago. Since then the vital physiological involvement of oxygen in various biologi­cal processes, mainly energy production, has been established. However, in the body molecular oxygen can be converted to toxic oxygen metabolites such as superoxide anion, hydrogen peroxide, the hydroxyl radical and singlet oxygen. These toxic metabolites are produced mainly in the mitochondria, plasma membranes and endoplasmic reticulum.

  16. South Dakota Middle School Mathematics Teachers' Perceptions of Teaching Competencies (United States)

    Bleecker, Heather A.


    This quantitative research study investigates South Dakota middle school (grades 5-8) mathematics teachers' perceptions of teaching competencies including general pedagogical knowledge (GPK) and mathematical pedagogical content knowledge (MPCK). The study also considered how teacher characteristics relate to teacher competencies. The study…

  17. Yellow phosphorus process to convert toxic chemicals to non-toxic products (United States)

    Chang, S.G.


    The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

  18. Implementing an excellence in teaching recognition system: needs analysis and recommendations. (United States)

    Schindler, Nancy; Corcoran, Julia C; Miller, Megan; Wang, Chih-Hsiung; Roggin, Kevin; Posner, Mitchell; Fryer, Jonathan; DaRosa, Debra A


    Teaching awards have been suggested to serve a variety of purposes. The specific characteristics of teaching awards and the associated effectiveness at achieving planned purposes are poorly understood. A needs analysis was performed to inform recommendations for an Excellence in Teaching Recognition System to meet the needs of surgical education leadership. We performed a 2-part needs analysis beginning with a review of the literature. We then, developed, piloted, and administered a survey instrument to General Surgery program leaders. The survey examined the features and perceived effectiveness of existing teaching awards systems. A multi-institution committee of program directors, clerkship directors, and Vice-Chairs of education then met to identify goals and develop recommendations for implementation of an "Excellence in Teaching Recognition System." There is limited evidence demonstrating effectiveness of existing teaching awards in medical education. Evidence supports the ability of such awards to demonstrate value placed on teaching, to inspire faculty to teach, and to contribute to promotion. Survey findings indicate that existing awards strive to achieve these purposes and that educational leaders believe awards have the potential to do this and more. Leaders are moderately satisfied with existing awards for providing recognition and demonstrating value placed on teaching, but they are less satisfied with awards for motivating faculty to participate in teaching or for contributing to promotion. Most departments and institutions honor only a few recipients annually. There is a paucity of literature addressing teaching recognition systems in medical education and little evidence to support the success of such systems in achieving their intended purposes. The ability of awards to affect outcomes such as participation in teaching and promotion may be limited by the small number of recipients for most existing awards. We propose goals for a Teaching Recognition

  19. Improving teaching on the basis of student evaluation: integrative teaching consultation. (United States)

    Wibbecke, Gerald; Kahmann, Janine; Pignotti, Tanja; Altenberger, Leander; Kadmon, Martina


    Due to the development of medical education in the past decade the role of teachers has changed and requires higher didactic competence. Student evaluation of teaching alone does not lead to considerable improvement of teaching quality. We present the concept of "Integrative Teaching Consultation", which comprises both the teacher's reflection and own objectives to improve their teaching as well as data from students ratings. Teachers in collaboration with a teaching consultant reflect on their teaching ability and set themselves improvement goals. Then the consultant himself observes a teaching session and subsequently analyses the respective student evaluation in order to give meaningful feedback to the teacher. The combination of student feedback with professional consultation elements can initiate and maintain improvements in teaching. Teaching consultation complements existing faculty development programs and increases the benefit of student evaluations.

  20. Biological cellular response to carbon nanoparticle toxicity

    International Nuclear Information System (INIS)

    Panessa-Warren, B J; Warren, J B; Wong, S S; Misewich, J A


    Recent advances in nanotechnology have increased the development and production of many new nanomaterials with unique characteristics for industrial and biomedical uses. The size of these new nanoparticles (<100 nm) with their high surface area and unusual surface chemistry and reactivity poses unique problems for biological cells and the environment. This paper reviews the current research on the reactivity and interactions of carbon nanoparticles with biological cells in vivo and in vitro, with ultrastructural images demonstrating evidence of human cell cytotoxicity to carbon nanoparticles characteristic of lipid membrane peroxidation, gene down regulation of adhesive proteins, and increased cell death (necrosis, apoptosis), as well as images of nontoxic carbon nanoparticle interactions with human cells. Although it is imperative that nanomaterials be systematically tested for their biocompatibility and safety for industrial and biomedical use, there are now ways to develop and redesign these materials to be less cytotoxic, and even benign to cell systems. With this new opportunity to utilize the unique properties of nanoparticles for research, industry and medicine, there is a responsibility to test and optimize these new nanomaterials early during the development process, to eliminate or ameliorate identified toxic characteristics

  1. Some Psychological Aspects of Aging: Implications for Teaching and Learning. (United States)

    Lersten, Kenneth C.

    This paper reviews psychological literature concerned with aging, and includes brief reviews of (a) motor skill work, (b) the phenomena of "slowing," (c) social psychological findings, (d) sensation and perception, and (e) selected learning characteristics. The following teaching and learning strategies were elicited from this study: (a)…

  2. Phylogenetic diversity of bacteria associated with toxic and non-toxic ...

    African Journals Online (AJOL)

    Phylogenetic diversity of bacteria associated with toxic and non-toxic strains of Alexandrium minutum. L Palacios, B Reguera, J Franco, I Marín. Abstract. Marine planktonic dinoflagellates are usually associated with bacteria, some of which seem to have a symbiotic relation with the dinoflagellate cells. The role of bacteria in ...

  3. A novel teaching tool using dynamic cues improves visualisation of chest lesions by naive observers (United States)

    Mohamed Ali, M. A.; Toomey, R. J.; Ryan, J. T.; Cuffe, F. C.; Brennan, P. C.


    Introduction Dynamic cueing is an effective way of stimulating perception of regions of interest within radiological images. This study explores the impact of a novel teaching tool using dynamic cueing for lesion detection on plain chest radiographs. Materials and methods Observer performance studies were carried out where 36 novices examined 30 chest images in random order. Half of these contained between one and three simulated pulmonary nodules. Three groups were investigated: A (control: no teaching tool), B (retested immediately after undergoing the teaching tool) and C (retested a week after undergoing the teaching tool). The teaching tool involved dynamically displaying the same images with and without lesions. Results were compared using Receiver Operating Characteristics (ROC), sensitivity and specificity analyses. Results The second reading showed significantly greater area under the ROC curve (Az value) (pchest radiographs in the short term.

  4. Toxic effects of zinc from trout farm sediments on ATP, protein, and hemoglobin concentrations of Limnodrilus hoffmeisteri. (United States)

    Martinez-Tabche, L; Gutiérrez Cabrera, I; Gómez Oliván, L; Galar Martinez, M; Germán Faz, C


    Zinc (Zn) is a nutritionally essential metal, and deficiency results in severe health consequences to aquatic organisms. In this study toxicity data for Limnodrilus hoffmeisteri produced by Zn in systems using three natural sediments (trout farms: El Oyamel, El Truchón, and El Potrero) are presented. Hemoglobin, adenosine triphosphate (ATP), and protein concentrations were measured in L. hoffmeisteri exposed to spiked sediments, as indicators of exposure. Physicochemical characteristics of water and sediments were also considered. Zn concentrations were measured in water and sediment. El Oyamel, El Truchón, and El Potrero pond sediments did not have similar physicochemical characteristics. Zn concentrations of water obtained from the rustic ponds were near 0.4575 mg/L; however, this metal was always found to be higher in the sediments (0.0271-0.9754 mg/kg). The bioassay with worms demonstrated that pond sediments from El Oyamel, El Potrero, and El Truchón produced toxicity since ATP and protein concentrations were low compared to controls (organisms without metal). All spiked sediments had a significant reduction effect on ATP, protein, and hemoglobin concentrations. This investigation clearly shows that sediments of El Truchón, El Oyamel, and El Potrero possess toxicity potential. These results suggest the usefulness of these bioassays to evaluate the toxicity of sediments polluted with heavy metals.

  5. Teaching Certificate Program Participants' Perceptions of Mentor-Mentee Relationships. (United States)

    Sheehan, Amy Heck; Gonzalvo, Jasmine D; Ramsey, Darin C; Sprunger, Tracy L


    Objective. To assess teaching certificate program (TCP) participants' perceptions of mentor-mentee relationships. Methods. A 15-item survey instrument was administered to all 2014-2015 participants of the Indiana Pharmacy Teaching Certificate (IPTeC) program. Results. One hundred percent of IPTeC program participants (83/83) responded to the survey. The majority of participants indicated that having a professional mentor was either very important (52%) or important (47%) to their professional development and preferred to choose their own professional mentor (53%). Mentor characteristics rated as highly important by mentees included having similar clinical practice interests (82%), having similar research interests (66%), and being available to meet face-to-face (90%). Age, race, and gender of the mentor were not rated by mentees as important. Conclusion. Teaching certificate program participants place high importance on having a professional mentor. Mentorship of pharmacists completing TCPs should be a priority for current pharmacy faculty members so adequate guidance is available to future pharmacy educators.

  6. Teaching preschool children to report suspicious packages to adults. (United States)

    May, Michael E; Shayter, Ashley M; Schmick, Ayla; Barron, Becky; Doherty, Meghan; Johnson, Matthew


    Law enforcement agencies stress that public reporting of terror-related crime is the predominant means for disrupting these actions. However, schools may be unprepared because the majority of the populace may not understand the threat of suspicious materials or what to do when they are found on school grounds. The purpose of this study was to systematically teach preschool children to identify and report suspicious packages across three experiments. In the first experiment, we used multiple exemplar training to teach children to identify the characteristics of safe and unsafe packages. In the second experiment, we taught participants to identify the locations where packages should be considered unsafe. Finally, in the third experiment, we used behavioral skills training to teach participants to avoid touching unsafe packages, leave the area where they were located, and report their discovery to an adult. Results suggest the participants quickly developed these skills. Implications for safety skills in young school children are discussed. © 2018 Society for the Experimental Analysis of Behavior.

  7. Teaching Psychiatry Residents to Teach: A National Survey (United States)

    Crisp-Han, Holly; Chambliss, R. Bryan; Coverdale, John


    Objective: Because there have been no previously published national surveys on teaching psychiatry residents about how to teach, the authors surveyed United States psychiatry program directors on what and how residents are taught about teaching. Methods: All psychiatry training programs across the United States were mailed a semistructured…

  8. Validating potential toxicity assays to assess petroleum hydrocarbon toxicity in polar soil. (United States)

    Harvey, Alexis Nadine; Snape, Ian; Siciliano, Steven Douglas


    Potential microbial activities are commonly used to assess soil toxicity of petroleum hydrocarbons (PHC) and are assumed to be a surrogate for microbial activity within the soil ecosystem. However, this assumption needs to be evaluated for frozen soil, in which microbial activity is limited by liquid water (θ(liquid)). Influence of θ(liquid) on in situ toxicity was evaluated and compared to the toxicity endpoints of potential microbial activities using soil from an aged diesel fuel spill at Casey Station, East Antarctica. To determine in situ toxicity, gross mineralization and nitrification rates were determined by the stable isotope dilution technique. Petroleum hydrocarbon-contaminated soil (0-8,000 mg kg(-1)), packed at bulk densities of 1.4, 1.7, and 2.0 g cm(-3) to manipulate liquid water content, was incubated at -5°C for one, two, and three months. Although θ(liquid) did not have a significant effect on gross mineralization or nitrification, gross nitrification was sensitive to PHC contamination, with toxicity decreasing over time. In contrast, gross mineralization was not sensitive to PHC contamination. Toxic response of gross nitrification was comparable to potential nitrification activity (PNA) with similar EC25 (effective concentration causing a 25% effect in the test population) values determined by both measurement endpoints (400 mg kg(-1) for gross nitrification compared to 200 mg kg(-1) for PNA), indicating that potential microbial activity assays are good surrogates for in situ toxicity of PHC contamination in polar regions. Copyright © 2011 SETAC.

  9. Didattica della musica ed insegnante efficace: un'indagine quantitativa Music teaching and the effective teacher: a quantitative study


    Concina, Eleonora


    Teaching and learning are two dimensions of the same educative process; it is a complex condition where the individual can meet and experience his or her own cultural and social system, sharing meanings, symbols, and languages (Frabboni, 1999). A condition of effective teaching may develop when the teacher puts into his or her professional activity some specific characteristics with the aim to promote students' learning and autonomy in the educational process. There are some aspects in teache...

  10. Improving teaching on the basis of student evaluation: Integrative teaching consultation

    Directory of Open Access Journals (Sweden)

    Wibbecke, Gerald


    Full Text Available Objective: Due to the development of medical education in the past decade the role of teachers has changed and requires higher didactic competence. Student evaluation of teaching alone does not lead to considerable improvement of teaching quality. We present the concept of "Integrative Teaching Consultation", which comprises both the teacher’s reflection and own objectives to improve their teaching as well as data from students ratings.Methods: Teachers in collaboration with a teaching consultant reflect on their teaching ability and set themselves improvement goals. Then the consultant himself observes a teaching session and subsequently analyses the respective student evaluation in order to give meaningful feedback to the teacher.Results: The combination of student feedback with professional consultation elements can initiate and maintain improvements in teaching. Conclusion: Teaching consultation complements existing faculty development programs and increases the benefit of student evaluations.

  11. Performance and Carcass Characteristics of Broiler Finisher Birds ...

    African Journals Online (AJOL)

    Sixty (60) 4 weeks old Anak broiler strain were subjected to 28 days feeding trial at the Poultry Unit of the Teaching and Research Farm, Evan Enwerem, Owerri, Nigeria, to determine the dietary effect of pineapple wine sediment (PWSM) on their performance and carcass characteristics. The birds were divided into four ...

  12. Analysis of application for situational teaching method in tourism English teaching

    Directory of Open Access Journals (Sweden)

    Li Jing


    Full Text Available Faced with China’s English teaching problems today, it is not enough to just know that the situational teaching method can be effectively applied in a wide range of English teaching, but there is a must to embody the specific application value of the situational teaching method. This paper first analyzes tourism English teaching in China through establishing the quantifiable group-index hierarchical structure model to obtain the optimal training program of China’s tourism English talents, and then carries out a detailed analysis of the application and role of the situational teaching method in training of the tourism English ability to obtain the specific application scope and application value of the situational teaching method in the tourism English teaching.

  13. Design and practice of a novel experiment teaching system based on the optoelectric information chain (United States)

    Luo, Yunhan; Chen, Zhe; Li, Yan; Di, Hongwei; Li, Zhen; Bai, Chunhe; Tang, Jieyuan; Zhang, Jun; Yi, Xiao


    The course of optoelectronic information science is a diverse science and technology with wide range of disciplines, intensive technology, and strong applicability. As a result, the practice teaching in undergraduate education occupies the strategic important position, which is a key link in the process of innovative talents cultivation of photoelectric information, plays a unique and irreplaceable role by any other teaching methods. In order to meet the requirements of national innovative talents of photoelectric information, the complete teaching reform strategy was put forward by combining with the higher education policy and development strategy of teaching and professional characteristics. The goal of the experimental teaching reform is to cultivate innovative talents and to construct the photoelectric information industry chain system of experimental teaching platform and cultivating creative personnel. The key clue is the photoelectric information surrounding photoelectric information, like "generation - modulation - transformation - detection - procession" which will be realized by resource integration and complementary among cross disciplines, and focusing on scientific research support for the teaching and the combination of professional knowledge and practical application. This teaching reform scheme presented in the paper will provide very good demonstration effect in the curriculum reform of other photoelectric information related courses.

  14. Teaching with Technology. Teaching in Focus. No. 12 (United States)

    OECD Publishing, 2015


    Information and communication technology (ICT) use has been identified as one of the more active teaching practices, which promote skills students need for success. And yet, less than 40% of teachers across Teaching and Learning International Survey (TALIS) countries report using ICT as a regular part of their teaching practice. Shortages in…

  15. α-Synuclein overexpression increases dopamine toxicity in BE(2-M17 cells

    Directory of Open Access Journals (Sweden)

    Miller David W


    Full Text Available Abstract Background Oxidative stress has been proposed to be involved in the pathogenesis of Parkinson's disease (PD. A plausible source of oxidative stress in nigral dopaminergic neurons is the redox reactions that specifically involve dopamine and produce various toxic molecules, i.e., free radicals and quinone species. α-Synuclein, a protein found in Lewy bodies characteristic of PD, is also thought to be involved in the pathogenesis of PD and point mutations and multiplications in the gene coding for α-synuclein have been found in familial forms of PD. Results We used dopaminergic human neuroblastoma BE(2-M17 cell lines stably transfected with WT or A30P mutant α-synuclein to characterize the effect of α-synuclein on dopamine toxicity. Cellular toxicity was analyzed by lactate dehydrogenase assay and by fluorescence-activated cell sorter analysis. Increased expression of either wild-type or mutant α-synuclein enhances the cellular toxicity induced by the accumulation of intracellular dopamine or DOPA. Conclusions Our results suggest that an interplay between dopamine and α-synuclein can cause cell death in a neuron-like background. The data presented here are compatible with several models of cytotoxicity, including the formation of α-synuclein oligomers and impairment of the lysosomal degradation.

  16. Factors Affecting Canadian Teachers' Willingness to Teach Sexual Health Education (United States)

    Cohen, Jacqueline N.; Byers, E. Sandra; Sears, Heather A.


    Non-specialist teachers in Canada are increasingly required to teach sexual health topics. However, research suggests that they do not always do so willingly. This study examined the associations between the characteristics of non-specialist elementary and middle school teachers (n = 294) in Canadian schools and their willingness to provide sexual…

  17. Kinetics of soil dehydrogenase in response to exogenous Cd toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Xiangping [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, CAS 723 Xingke Rd., Tianhe District, Guangzhou 510650 (China); Wang, Ziquan; Lu, Guannan [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); He, Wenxiang, E-mail: [College of Natural Resources and Environment, Northwest A& F University, Yangling, 712100, Shaanxi (China); Key Laboratory of Plant Nutrition and Agro-environment in Northwest China, Ministry of Agriculture, Northwest A& F University, Yangling, 712100, Shaanxi (China); Wei, Gehong [College of Life Sciences, Northwest A& F University, Yangling, 712100, Shaanxi (China); Huang, Feng; Xu, Xinlan; Shen, Weijun [Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, CAS 723 Xingke Rd., Tianhe District, Guangzhou 510650 (China)


    Highlights: • pH explained 30–45% of the dehydrogenase activity (DHA), V{sub max}, and K{sub m} variations across soils. • Different inhibition mechanism of Cd to DHA varied soil types. • Soil properties and inhibition constant affect the toxicity of Cd. • Reaction constant (k) could indicate sensitively the toxicity of Cd to DHA. - Abstract: Soil dehydrogenase plays a role in the biological oxidation of soil organic matter and can be considered a good measure of the change of microbial oxidative activity under environmental pollutions. However, the kinetic characteristic of soil dehydrogenase under heavy metal stresses has not been investigated thoroughly. In this study, we characterized the kinetic characteristic of soil dehydrogenase in 14 soil types, and investigated how kinetic parameters changed under spiked with different concentrations of cadmium (Cd). The results showed that the K{sub m} and V{sub max} values of soil dehydrogenase was among 1.4–7.3 mM and 15.9–235.2 μM h{sup −1} in uncontaminated soils, respectively. In latosolic red soil and brown soil, the inhibitory kinetic mechanism of Cd to soil dehydrogenase was anticompetitive inhibition with inhibition constants (K{sub i}) of 12 and 4.7 mM, respectively; in other soils belonged to linear mixed inhibition, the values of K{sub i} were between 0.7–4.2 mM. Soil total organic carbon and K{sub i} were the major factors affecting the toxicity of Cd to dehydrogenase activity. In addition, the velocity constant (k) was more sensitive to Cd contamination compared to V{sub max} and K{sub m}, which was established as an early indicator of gross changes in soil microbial oxidative activity caused by Cd contamination.

  18. Co-Teaching in Student Teaching of an Elementary Education Program (United States)

    Chang, Sau Hou


    Successful co-teaching relied on essential elements and different approaches. However, few studies were found on these essential elements and different approaches in student teaching. The objective of this study was to examine how teacher candidates and cooperating teachers used the essential co-teaching elements and co-teaching approaches.…

  19. Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms (United States)

    Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.


    Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ≤ 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

  20. Teaching Creatively and Teaching for Creativity (United States)

    Brinkman, David J.


    This article provides a brief review of generally accepted ideas about creativity, followed by examples of music teachers teaching creatively and teaching their students to be more creative. Implications for teacher education and policy recommendations for music education are discussed.

  1. Both preparing to teach and teaching positively impact learning outcomes for peer teachers. (United States)

    Gregory, Alexander; Walker, Ian; McLaughlin, Kevin; Peets, Adam D


    We sought to evaluate the independent effects of preparing to teach and teaching on peer teacher learning outcomes. To evaluate the independent contributions of both preparing to teach and teaching to the learning of peer teachers in medical education. In total, 17 third-year medical students prepared to teach second-year students Advanced Cardiac Life Support algorithms and electrocardiogram (ECG) interpretation. Immediately prior to teaching they were randomly allocated to not teach, to teach algorithms, or to teach ECG. Peer teachers were tested on both topics prior to preparation, immediately after teaching and 60 days later. Compared to baseline, peer teachers' mean examination scores (±SD) demonstrated the greatest gains for content areas they prepared for and then taught (43.0% (13.9) vs. 66.3% (8.8), p teach but did not teach, less dramatic gains were evident (43.6% (8.3) vs. 54.7% (9.4), p teaching were greater than those for preparation (23.3% (10.9) vs. 8% (9.6), p teach and actively teaching may have independent positive effects on peer teacher learning outcomes.

  2. Teaching efficacy of nurses in clinical practice education: A cross-sectional study. (United States)

    Kim, Eun-Kyeung; Shin, Sujin


    Clinical nurses play a vital role in clinical practice education; thus, it is necessary to help clinical nurses have teaching efficacy through the development and application of systematic education programs. To identify nurses' teaching efficacy for clinical education and analyze the influencing factors of teaching efficacy. The study used a cross-sectional design. We used a convenience sample of 263 nurses from two hospitals. Teaching efficacy, general characteristics, and perception of clinical practice education were collected via self-reported questionnaires. Teaching efficacy was measured using Hwang's (2006) questionnaire, while perception of clinical practice education was measured using the Clinical Nurse Teacher Survey developed by Nishioka et al. (2014). Participants completed the questionnaire directly. The collected data were then analyzed using descriptive statistics, t-tests, ANOVAs, and multiple regression analysis with PASW Statistics 18.0. The mean total score of teaching efficacy was 72.5 (range 21-105). The leadership for students subscale had the highest score (3.56±0.59). The factors influencing teaching efficacy were length of clinical career (β=0.26, pteaching efficacy in nurses. Based on these results, nursing educators might need to develop greater confidence in their knowledge and enhance control of their teaching strategies. Nursing schools and hospitals might need to provide greater support and educational opportunities to nurse clinical practice instructors. Furthermore, constructing a system of cooperation between these colleges and educational hospitals, developing programs to enhance teaching efficacy, and identifying the clinical instructor's role are all necessary to promote clinical practice education. Copyright © 2017. Published by Elsevier Ltd.

  3. Teaching Listening (United States)

    Nemtchinova, Ekaterina


    Ekaterina Nemtchinova's book "Teaching Listening" explores different approaches to teaching listening in second language classrooms. Presenting up-to-date research and theoretical issues associated with second language listening, Nemtchinova explains how these new findings inform everyday teaching and offers practical suggestions…

  4. Evaluation matters: lessons learned on the evaluation of surgical teaching. (United States)

    Woods, Nicole N


    The traditional system of academic promotion and tenure can make it difficult to reward those who excel at surgical teaching. A successful faculty evaluation process can provide the objective measures of teaching performance needed for performance appraisals and promotion decisions. Over the course of two decades, an extensive faculty evaluation process has been developed in the Department of Surgery at the University of Toronto. This paper presents some of the non-psychometric characteristics of that system. Faculty awareness of the evaluation process, the consistency of its application, trainee anonymity and the materiality of the results are described key factors of a faculty evaluation system that meets the assessment needs of individual teachers and raises the profile of teaching in surgical departments. Copyright © 2010 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  5. Research and Teaching PA: Towards Research as Teaching (United States)

    van der Meer, Frans-Bauke; Marks, Peter


    Research and teaching are core business of academic institutions. The research context is thought to be fruitful for teaching and learning, and students may contribute to research. But how exactly does the interplay between research and teaching take place and how, in what respects and under which conditions, does this contribute to the quality of…

  6. Evaluation of metals, metalloids, and ash mixture toxicity using sediment toxicity testing. (United States)

    Stojak, Amber; Bonnevie, Nancy L; Jones, Daniel S


    In December 2008, a release of 4.1 million m(3) of coal ash from the Tennessee Valley Authority Kingston Fossil Plant occurred. Ash washed into the Emory River and migrated downstream into the Clinch and Tennessee Rivers. A Baseline Ecological Risk Assessment evaluated risks to ecological receptors from ash in the river system post-dredging. This article describes the approach used and results from sediment toxicity tests, discussing any causal relationships between ash, metals, and toxicity. Literature is limited in the realm of aquatic coal combustion residue (CCR) exposures and the potential magnitude of effects on benthic invertebrates. Sediment samples along a spectrum of ash content were used in a tiered toxicity testing approach and included a combination of 10 day sediment toxicity acute tests and longer-term, partial life cycle "definitive" tests with 2 species (Hyalella azteca and Chironomus dilutus). Arsenic, and to a lesser extent Se, in the ash was the most likely toxicant causing observed effects in the laboratory toxicity tests. Sites in the Emory River with the greatest statistical and biologically significant effects had As concentrations in sediments twice the probable effects concentration of 33 mg/kg. These sites contained greater than 50% ash. Sites with less than approximately 50% ash in sediments exhibited fewer significant toxic responses relative to the reference sediment in the laboratory. The results discussed here present useful evidence of only limited effects occurring from a worst-case exposure pathway. These results provided a valuable line of evidence for the overall assessment of risks to benthic invertebrates and to other ecological receptors, and were crucial to risk management and development of project remediation goals. © 2014 SETAC.

  7. Toxicity of Single and Mixed Contaminants in Seawater Measured with Acute Toxicity Bioassays

    Directory of Open Access Journals (Sweden)

    A.R. Fernandez-Alba


    Full Text Available Different types of organic pollutants commonly detected in seawater have been evaluated by acute toxicity bioassays. Vibrio fischeri, Daphnia magna, and Selenastrum capricornotum were selected to test toxic effects of individual compounds and mixtures of these compounds, obtaining EC50 values in the range of 0.001 to 28.9 mg/l. In the case of mixtures, synergistic toxic responses were seen for a clear majority of the cases (>60%. Mixtures containing methyl-tertiary-butyl ether (MTBE exhibit accelerated processes that result in a change in concentration required to produce a toxic effect; for example, in the case of mixtures containing MTBE and Diuron and Dichlofluanid.

  8. Effect of steam activation of biochar produced from a giant Miscanthus on copper sorption and toxicity. (United States)

    Shim, Taeyong; Yoo, Jisu; Ryu, Changkook; Park, Yong-Kwon; Jung, Jinho


    This study aims to evaluate the physiochemical properties, sorption characteristics, and toxicity effects of biochar (BC) produced from Miscanthus sacchariflorus via slow pyrolysis at 500°C and its steam activation product (ABC). Although BC has a much lower surface area than ABC (181 and 322m(2)g(-1), respectively), the Cu sorption capacities of BC and ABC are not significantly different (p>0.05). A two-compartment model successfully explains the sorption of BC and ABC as being dominated by fast and slow sorption processes, respectively. In addition, both BC and ABC efficiently eliminate the toxicity of Cu towards Daphnia magna. However, ABC itself induced acute toxicity to D. magna, which is possibly due to increased aromaticity upon steam activation. These findings suggest that activation of BC produced from M. sacchariflorus at a pyrolytic temperature of 500°C may not be appropriate in terms of Cu sorption and toxicity reduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Building a developmental toxicity ontology. (United States)

    Baker, Nancy; Boobis, Alan; Burgoon, Lyle; Carney, Edward; Currie, Richard; Fritsche, Ellen; Knudsen, Thomas; Laffont, Madeleine; Piersma, Aldert H; Poole, Alan; Schneider, Steffen; Daston, George


    As more information is generated about modes of action for developmental toxicity and more data are generated using high-throughput and high-content technologies, it is becoming necessary to organize that information. This report discussed the need for a systematic representation of knowledge about developmental toxicity (i.e., an ontology) and proposes a method to build one based on knowledge of developmental biology and mode of action/ adverse outcome pathways in developmental toxicity. This report is the result of a consensus working group developing a plan to create an ontology for developmental toxicity that spans multiple levels of biological organization. This report provide a description of some of the challenges in building a developmental toxicity ontology and outlines a proposed methodology to meet those challenges. As the ontology is built on currently available web-based resources, a review of these resources is provided. Case studies on one of the most well-understood morphogens and developmental toxicants, retinoic acid, are presented as examples of how such an ontology might be developed. This report outlines an approach to construct a developmental toxicity ontology. Such an ontology will facilitate computer-based prediction of substances likely to induce human developmental toxicity. © 2018 Wiley Periodicals, Inc.

  10. Joint use of laboratory bioassays and field-collected plants to evaluate toxicity and contaminant bioaccumulation

    International Nuclear Information System (INIS)

    Long, S.P.; Byron, E.R.; Ohlendorf, H.M.


    Soil toxicity tests using lettuce (Latuca saliva) were conducted using soil samples collected as part of ecological risk assessments at two facilities in California. At some sites, terrestrial plants were collected in the field for chemical analysis. Ecological concerns focused on exposures to plants, phytophagous insects, and their secondary consumers, such as birds and small mammals. The toxicity tests were used to assess potential exposures to a variety of site-specific contaminants including organochlorine pesticides, PCBs, PAHs, petroleum hydrocarbons, heavy metals, and other inorganic substances. Site soils were combined with clean control soils to produce toxicity test soil dilutions containing 100%, 75%, 50%, 25%, and 0% site soils. Observations of seed germination and growth were made at day 0, 7, 14, 21 and 28. Toxicity test results were combined with soil chemical analytical results and physical characteristics to establish NOAELs and LOAELs. Bioaccumulation in the lettuce and field-collected plants was evaluated by comparing plant contaminant to soil contaminant concentrations. Allometric equations and sublethal toxicity data were used to predict potential effects on birds and small mammals. Whole-body contaminant concentrations in insects collected on some of the plants in the field were also considered in evaluating the potential for toxicity to insectivorous birds. The study indicated that contaminant uptake was occurring in the field-collected and bioassay plants but not the insects. Site factors in addition to soil contaminant concentration influenced the potential for plant toxicity and bioaccumulation

  11. The Four-Phase Model of Interest Development applied to learning to teach

    Directory of Open Access Journals (Sweden)

    George Francisco Santiago Martin


    Full Text Available This article presents a research about the development of interest in teaching. The subjects of study were students of a public University of Paraná, Brazil, who integrated the a project in initial training called PIBID in scientific areas (Biological Sciences, Physics and Chemistry. The methodological procedures were based on the discursive textual analysis, from which it was possible to organize the data according to the Four-Phases Model of Interest Development (MDI of Hidi and Renninger (2006. After analysis, it was possible to characterize the interest of these students in teaching, suggesting that this interest can be developed in students during initial training. Our data showed, moreover, that interest in teaching has two main characteristics: the desire to be a teacher and the curiosity of the students to know how is to be a teacher. In addition, it was found that the school teachers can directly influence the maintenance of student interest in following a teaching career.

  12. The teaching researcher: faculty attitudes towards the teaching and research roles (United States)

    Alpay, E.; Verschoor, R.


    Results from a survey on faculty attitudes towards the teaching and research roles are presented. Attention is given to: (i) the perceived value of teaching (and teaching achievements) relative to research, (ii) approaches for research and teaching integration, (iii) the satisfaction gained from typical work tasks, and (iv) the importance of various work-life factors. Factors such as academic freedom, an intellectual work environment, flexible work hours, inspirational colleagues, and work diversity are found to be highly valued. Support from peers and colleagues is also seen as a key in learning to manage the different academic roles. A relatively low value is attributed to teaching achievements. Likewise, there is often little utilisation of teaching opportunities to support research work (other than senior-year research projects). Female faculty were found to give marginally a higher importance to teaching recognition and collaborative teaching opportunities. Based on the findings, general recommendations for supporting the teaching researcher are presented.

  13. Mechanisms of Phosphine Toxicity

    Directory of Open Access Journals (Sweden)

    Nisa S. Nath


    Full Text Available Fumigation with phosphine gas is by far the most widely used treatment for the protection of stored grain against insect pests. The development of high-level resistance in insects now threatens its continued use. As there is no suitable chemical to replace phosphine, it is essential to understand the mechanisms of phosphine toxicity to increase the effectiveness of resistance management. Because phosphine is such a simple molecule (PH3, the chemistry of phosphorus is central to its toxicity. The elements above and below phosphorus in the periodic table are nitrogen (N and arsenic (As, which also produce toxic hydrides, namely, NH3 and AsH3. The three hydrides cause related symptoms and similar changes to cellular and organismal physiology, including disruption of the sympathetic nervous system, suppressed energy metabolism and toxic changes to the redox state of the cell. We propose that these three effects are interdependent contributors to phosphine toxicity.

  14. Multivariate normal tissue complication probability modeling of gastrointestinal toxicity after external beam radiotherapy for localized prostate cancer

    International Nuclear Information System (INIS)

    Cella, Laura; D’Avino, Vittoria; Liuzzi, Raffaele; Conson, Manuel; Doria, Francesca; Faiella, Adriana; Loffredo, Filomena; Salvatore, Marco; Pacelli, Roberto


    The risk of radio-induced gastrointestinal (GI) complications is affected by several factors other than the dose to the rectum such as patient characteristics, hormonal or antihypertensive therapy, and acute rectal toxicity. Purpose of this work is to study clinical and dosimetric parameters impacting on late GI toxicity after prostate external beam radiotherapy (RT) and to establish multivariate normal tissue complication probability (NTCP) model for radiation-induced GI complications. A total of 57 men who had undergone definitive RT for prostate cancer were evaluated for GI events classified using the RTOG/EORTC scoring system. Their median age was 73 years (range 53–85). The patients were assessed for GI toxicity before, during, and periodically after RT completion. Several clinical variables along with rectum dose-volume parameters (Vx) were collected and their correlation to GI toxicity was analyzed by Spearman’s rank correlation coefficient (Rs). Multivariate logistic regression method using resampling techniques was applied to select model order and parameters for NTCP modeling. Model performance was evaluated through the area under the receiver operating characteristic curve (AUC). At a median follow-up of 30 months, 37% (21/57) patients developed G1-2 acute GI events while 33% (19/57) were diagnosed with G1-2 late GI events. An NTCP model for late mild/moderate GI toxicity based on three variables including V65 (OR = 1.03), antihypertensive and/or anticoagulant (AH/AC) drugs (OR = 0.24), and acute GI toxicity (OR = 4.3) was selected as the most predictive model (Rs = 0.47, p < 0.001; AUC = 0.79). This three-variable model outperforms the logistic model based on V65 only (Rs = 0.28, p < 0.001; AUC = 0.69). We propose a logistic NTCP model for late GI toxicity considering not only rectal irradiation dose but also clinical patient-specific factors. Accordingly, the risk of G1-2 late GI increases as V65 increases, it is higher for patients experiencing

  15. Toxicity Estimation Software Tool (TEST) (United States)

    The Toxicity Estimation Software Tool (TEST) was developed to allow users to easily estimate the toxicity of chemicals using Quantitative Structure Activity Relationships (QSARs) methodologies. QSARs are mathematical models used to predict measures of toxicity from the physical c...

  16. Distributed Structure Searchable Toxicity (United States)

    U.S. Environmental Protection Agency — The Distributed Structure Searchable Toxicity (DSSTox) online resource provides high quality chemical structures and annotations in association with toxicity data....

  17. The Teaching of Language or The Teaching of Communication?

    Directory of Open Access Journals (Sweden)

    Rodolfo Acosta Padrón


    Full Text Available This article shows the position of the author about the dilemma in language teaching of what is primary: the teaching of communicative skills or the knowledge of the language system. Some concepts are clarified and lead to the nec essity to conceive a language teaching - learning process that takes into account what constitute appropriate (pragmatic as well as correct language behavior (activity in the teaching of both the mother tongue and the foreign languages.

  18. Exploring the Impact of Toxic Attitudes and a Toxic Environment on the Veterinary Healthcare Team. (United States)

    Moore, Irene C; Coe, Jason B; Adams, Cindy L; Conlon, Peter D; Sargeant, Jan M


    The objective of this qualitative study was to compare veterinarians' and Registered Veterinary Technicians' (RVT's) perceptions of the veterinary healthcare team with respect to the impact of toxic attitudes and a toxic environment. Focus group interviews using a semi-structured interview guide and follow up probes were held with four veterinarian groups (23 companion animal veterinarians) and four Registered Veterinary Technician groups (26 RVTs). Thematic analysis of the discussions indicated both veterinarian and RVT participants felt team members with manifestations of toxic attitudes negatively impacted veterinary team function. These manifestations included people being disrespectful, being resistant to change, always wanting to be the "go to person," avoiding conflict, and lacking motivation. When conflict was ignored, or when people with toxic attitudes were not addressed, a toxic environment often resulted. A toxic environment sometimes manifested when "broken communication and tension between staff members" occurred as a result of employees lacking confidence, skills, or knowledge not being managed properly. It also occurred when employees did not feel appreciated, when there was difficulty coping with turnover, and when there were conflicting demands. The presence of people manifesting a toxic attitude was a source of frustration for both veterinarian and RVT participants. Prompt and consistent attention to negative behaviors is recommended to reduce the development of a toxic environment.

  19. Bioaccumulation and Toxicity of Carbon Nanoparticles Suspension Injection in Intravenously Exposed Mice

    Directory of Open Access Journals (Sweden)

    Ping Xie


    Full Text Available Carbon nanoparticles suspension injection (CNSI has been widely used in tumor drainage lymph node mapping, and its new applications in drug delivery, photothermal therapy, and so on have been extensively investigated. To develop new clinical applications, the toxicity of CNSI after intravenous exposure should be thoroughly investigated to ensure its safe use. Herein, we studied the bioaccumulation of CNSI in reticuloendothelial system (RES organs and the corresponding toxicity to mice. After the intravenous injection of CNSI, no abnormal behavior of mice was observed during the 28-day observation period. The body weight increases were similar among the exposed groups and the control group. The parameters of hematology and serum biochemistry remained nearly unchanged, with very few of them showing significant changes. The low toxicity of CNSI was also reflected by the unchanged histopathological characteristics of these organs. The injection of CNSI did not induce higher apoptosis levels either. The slight oxidative stress was observed in RES organs at high dosages at day 7 post-exposure. The implication to the clinical applications and toxicological evaluations of carbon nanomaterials is discussed.


    Liu, Suyu; Yin, Guosheng; Yuan, Ying


    A major practical impediment when implementing adaptive dose-finding designs is that the toxicity outcome used by the decision rules may not be observed shortly after the initiation of the treatment. To address this issue, we propose the data augmentation continual re-assessment method (DA-CRM) for dose finding. By naturally treating the unobserved toxicities as missing data, we show that such missing data are nonignorable in the sense that the missingness depends on the unobserved outcomes. The Bayesian data augmentation approach is used to sample both the missing data and model parameters from their posterior full conditional distributions. We evaluate the performance of the DA-CRM through extensive simulation studies, and also compare it with other existing methods. The results show that the proposed design satisfactorily resolves the issues related to late-onset toxicities and possesses desirable operating characteristics: treating patients more safely, and also selecting the maximum tolerated dose with a higher probability. The new DA-CRM is illustrated with two phase I cancer clinical trials. PMID:24707327

  1. Effects of particulate oxidation catalyst on unregulated pollutant emission and toxicity characteristics from heavy-duty diesel engine. (United States)

    Feng, Xiangyu; Ge, Yunshan; Ma, Chaochen; Tan, Jianwei


    To evaluate the effects of particulate oxidation catalyst (POC) on unregulated pollutant emission and toxicity characteristics, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), soot, soluble organic fractions (SOF) and sulphate emissions emitted from a heavy-duty diesel engine retrofitted with a POC were investigated on a diesel bench. The particulate matter (PM) in the exhaust was collected by Teflon membrane, and the PAHs and VOCs were analysed by a gas chromatography/mass spectrometer (GC/MS). The results indicate that the POC exhibits good performance on the emission control of VOCs, PAHs and PM. The POC and the diesel particulate filters (DPF) both show a good performance on reducing the VOCs emission. Though the brake-specific emission (BSE) reductions of the total PAHs by the POC were lower than those by the DPF, the POC still removed almost more than 50% of the total PAHs emission. After the engine was retrofitted with the POC, the reductions of the PM mass, SOF and soot emissions were 45.2-89.0%, 7.8-97.7% and 41.7-93.3%, respectively. The sulphate emissions decreased at low and medium loads, whereas at high load, the results were contrary. The PAHs emissions were decreased by 32.4-69.1%, and the contributions of the PAH compounds were affected by the POC, as well as by load level. The benzo[a]pyrene equivalent (BaPeq) of PAHs emissions were reduced by 35.9-97.6% with the POC. The VOCs emissions were reduced by 21.8-94.1% with the POC, and the reduction was more evident under high load.

  2. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.


    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  3. Behavioral Patterns in Special Education. Good Teaching Practices. (United States)

    Rodríguez-Dorta, Manuela; Borges, África


    Providing quality education means to respond to the diversity in the classroom. The teacher is a key figure in responding to the various educational needs presented by students. Specifically, special education professionals are of great importance as they are the ones who lend their support to regular classroom teachers and offer specialized educational assistance to students who require it. Therefore, special education is different from what takes place in the regular classroom, demanding greater commitment by the teacher. There are certain behaviors, considered good teaching practices, which teachers have always been connected with to achieve good teaching and good learning. To ensure that these teachers are carrying out their educational work properly it is necessary to evaluate. This means having appropriate instruments. The Observational Protocol for Teaching Functions in Primary School and Special Education (PROFUNDO-EPE, v.3., in Spanish) allows to capture behaviors from these professionals and behavioral patterns that correspond to good teaching practices. This study evaluates the behavior of two special education teachers who work with students from different educational stages and educational needs. It reveals that the analyzed teachers adapt their behavior according the needs and characteristics of their students to the students responding more adequately to the needs presented by the students and showing good teaching practices. The patterns obtained indicate that they offer support, help and clear guidelines to perform the tasks. They motivate them toward learning by providing positive feedback and they check that students have properly assimilated the contents through questions or non-verbal supervision. Also, they provide a safe and reliable climate for learning.

  4. Being at peace as an important factor in acquiring teaching competency by Iranian nurse teachers: a qualitative study. (United States)

    Emamzadeh Ghasemi, Hormat Sadat; Rafii, Forough; Farahani, Mansoureh A; Mohammadi, Nooreddin


    It is imperative to understand the factor that influence teaching competency. Therefore, it is necessary to study those that have an impact on the process of acquiring teaching competency. Competent nurse teachers have an important role in the achievement of nursing students and improving the quality of nursing education. However, few researches have focused specifically on the process of acquiring teaching competency in nurse teachers and its related factors. This study as a part of more extensive research aims to explore the factors influencing acquisition of teaching competency by Iranian nurse teachers. Grounded theory was chosen as the method. Eleven teachers from three nursing schools in Tehran were recruited. Data was generated by semi structured interviews during May 2011 to March 2013 and was analyzed through using constant comparison. Three main categories were emerged including "individual characteristics" (spirituality, professional interest, ethical conducts, knowledge expansion and reflective practice), "organizational factors" (management of educational systems, solidarity culture, student characteristics) and "socio-cultural factors" (social situations, and public definition of nursing). Nurse teachers who deal peacefully with the nursing profession and colleagues are responsible and committed to acquiring teaching competency. A suitable organization in nursing educational systems that is structured and ordered also encourages a peaceful approach by nurse teachers.

  5. The Effects of Temperature and Hydrostatic Pressure on Metal Toxicity: Insights into Toxicity in the Deep Sea. (United States)

    Brown, Alastair; Thatje, Sven; Hauton, Chris


    Mineral prospecting in the deep sea is increasing, promoting concern regarding potential ecotoxicological impacts on deep-sea fauna. Technological difficulties in assessing toxicity in deep-sea species has promoted interest in developing shallow-water ecotoxicological proxy species. However, it is unclear how the low temperature and high hydrostatic pressure prevalent in the deep sea affect toxicity, and whether adaptation to deep-sea environmental conditions moderates any effects of these factors. To address these uncertainties we assessed the effects of temperature and hydrostatic pressure on lethal and sublethal (respiration rate, antioxidant enzyme activity) toxicity in acute (96 h) copper and cadmium exposures, using the shallow-water ecophysiological model organism Palaemon varians. Low temperature reduced toxicity in both metals, but reduced cadmium toxicity significantly more. In contrast, elevated hydrostatic pressure increased copper toxicity, but did not affect cadmium toxicity. The synergistic interaction between copper and cadmium was not affected by low temperature, but high hydrostatic pressure significantly enhanced the synergism. Differential environmental effects on toxicity suggest different mechanisms of action for copper and cadmium, and highlight that mechanistic understanding of toxicity is fundamental to predicting environmental effects on toxicity. Although results infer that sensitivity to toxicants differs across biogeographic ranges, shallow-water species may be suitable ecotoxicological proxies for deep-sea species, dependent on adaptation to habitats with similar environmental variability.

  6. Comics in language and literature teaching in lower primary school grades: Instructional potential

    Directory of Open Access Journals (Sweden)

    Stojanović Buba D.


    Full Text Available The purpose of this paper is presenting possibilities for using comics in teaching mother tongue, literature and linguistic culture in foreign language teaching, specifically the English language. Comics in teaching can motivate students to experience literary creation, to comprehend grammatical categories and spelling rules more completely or to be the feedback on the experience of what has been read. They boost the reading perception of students and develop students' ability to separate the key segments which are represented by picture and text. In modern age, dominated by digital media, comics surely deserve a special place in teaching in order to consolidate the value of books. The paper presents elements of comics, their structure and role the in teaching language and literature. Comics are visual aids for communication characterized by time dimension which is achieved by ordering scenes, which makes them similar to film. Their important characteristic is simultaneous expression by picture and text, which makes it a powerful aid in teaching language and literature. Dialogues are typical for comics, as well as dynamic storyline, which makes them especially interesting to students. Brief remarks on the historical development of comics are given because of the review on their general development, as well as on the possibilities for their application in teaching. The reading crisis occurs when children start school because they are supposed to acquire complex mental skills-technique of reading and writing. When aversion to the written media is obvious, comics can be of great help. The paper illustrates the use of comics in teaching literature, grammar, and linguistic culture as the motivational tool for reading and analysing a literary text. Special emphasis is placed on the possibilities of motivation to experience literary creation. Stimulated by comics, with compulsory reading, students can experience the work in pictures, which they will

  7. Challenges and Difficulties to Teaching Engineering to Generation Z: a case research

    Directory of Open Access Journals (Sweden)

    Suamit Correia Barreiro


    Full Text Available Many people from generation Z are at the beginning of their academic activities. This generation has peculiar characteristics that might be a challenge in the labor market. Thus, instructors have a great role in their preparation. However, professors might face difficulties dealing with their specific characteristics. The research aims to carry out a general survey to enable an understanding of the greater challenges and difficulties in teaching the subject of engineering to the students of Generation Z. The research method used was a case study at a University with 20 instructors from the Faculty of Engineering. The analysis revealed a great challenge in relating theoretical concepts with practical concepts. The research also showed a probable tendency of using more exhibition methods, and the low knowledge about generation Z by most instructors. This study seeks to contribute to the teaching-learning process of engineering.

  8. Dependence of Nanoparticle Toxicity on Their Physical and Chemical Properties (United States)

    Sukhanova, Alyona; Bozrova, Svetlana; Sokolov, Pavel; Berestovoy, Mikhail; Karaulov, Alexander; Nabiev, Igor


    Studies on the methods of nanoparticle (NP) synthesis, analysis of their characteristics, and exploration of new fields of their applications are at the forefront of modern nanotechnology. The possibility of engineering water-soluble NPs has paved the way to their use in various basic and applied biomedical researches. At present, NPs are used in diagnosis for imaging of numerous molecular markers of genetic and autoimmune diseases, malignant tumors, and many other disorders. NPs are also used for targeted delivery of drugs to tissues and organs, with controllable parameters of drug release and accumulation. In addition, there are examples of the use of NPs as active components, e.g., photosensitizers in photodynamic therapy and in hyperthermic tumor destruction through NP incorporation and heating. However, a high toxicity of NPs for living organisms is a strong limiting factor that hinders their use in vivo. Current studies on toxic effects of NPs aimed at identifying the targets and mechanisms of their harmful effects are carried out in cell culture models; studies on the patterns of NP transport, accumulation, degradation, and elimination, in animal models. This review systematizes and summarizes available data on how the mechanisms of NP toxicity for living systems are related to their physical and chemical properties.

  9. The dioxins - essential characteristics. Pt. 1

    International Nuclear Information System (INIS)

    Brunn, H.


    Polychlorinated dibenzo-p-dioxins (PCDD) belong to the group of persistent chlorinated hydrocarbons. They are predominantly of anthropogenic origin, except for those originating from fires caused by lightning or volcanic eruption. PCDD, according to the present knowledge, are absolutely useless. They are toxic, lipophilic, hardly degradable, and therefore ubiquitous in environment and food chain. PCDD have also been found in breast milk. Because their carcinogenic mechanism of action is little known, the toxicological evaluation of PCDD is still incomplete. Even lowest concentrations of PCDD may be detrimental to health. These characteristics are reason with enough to group PCDD not with xenobiotics, but with harmful substances. Closely related to PCDD in their origin and characteristics are polychlorinated dibenzofuranes (PCDF), which therefore are frequently ranked among ''the dioxins'': Essential characteristics of PCDD and PCDF are discussed. (orig.) [de

  10. Iodine 125 prostate brachytherapy: prognostic factors for long-term urinary, digestive and sexual toxicities

    International Nuclear Information System (INIS)

    Doyen, J.; Mohammed Ali, A.; Ginot, A.; Ferre, M.; Castelli, J.; Hannoun-Levi, J.M.; Chamorey, E.; Mohammed Ali, A.; Quintens, H.; Amiel, J.


    Purpose For patients with good urinary function and presenting with a low risk prostate cancer, prostate brachytherapy using iodine implants represents one of the techniques of reference. This retrospective analysis investigates urinary (U), digestive (D) and sexual (S) toxicities and their prognostic factors of duration. Material and methods From August 2000 to November 2007, 176 patients presenting with prostate adenocarcinoma underwent interstitial brachytherapy. Urinary, digestive and sexual toxicities were classified according to Common toxicities criteria for adverse events, version 3.0 (C.T.C.A.E. V 3.0). For each toxicity (U, D, S), the number of complications U (dysuria, nicturia), D (proctitis, diarrhea) and S (sexual dysfunction, loss of libido) was listed and analyzed according to criteria related to the patient, implant, dosimetric data and characteristics of the toxicity. Prognostic factors identified in univariate analysis (U.V.A.) (Log Rank) were further analyzed in multivariate analysis (M.V.A.) (Cox model). Results With a median follow-up of 26 months (1-87), 147 patients (83.5 %) presented urinary toxicities. Among them, 29.5 % (86 patients) and 2.4 % (seven patients) presented grade 2 and 3 U toxicity respectively. In U.V.A., urinary grade toxicity greater than or equal to 2 (p = 0.037), the presence of initial U symptoms (p = 0.027) and more than two urinary toxicities (p 0.00032) were recognized as prognostic factors. The number of U toxicities was the only prognostic factor in M.V.A. (p = 0.04). D toxicity accounted for 40.6 % (71 patients). Among them, 3 % (six patients) were grade 2. None were grade 3. Two factors were identified as prognostic factors either in U.V.A. and M.V.A.: the number of D toxicities greater than or equal to 2 (univariate analysis: p = 0,00129, multivariate analysis: p = 0,002) and age less than or equal to 65 years (univariate analysis: p = 0,004, multivariate analysis: p 0,007). Eighty-three patients (47

  11. Teaching the Millennial Generation in the Religious and Theological Studies Classroom (United States)

    Bauman, Whitney; Marchal, Joseph A.; McLain, Karline; O'Connell, Maureen; Patterson, Sara M.


    This essay provides an overview of the distinctive challenges presented to teaching and learning in religious and theological studies by the conditions and characteristics of "millennial" students. While the emerging literature on this generation is far from consistent, it is still instructive and important to engage, as students that…

  12. Are Electronic Books Effective in Teaching Young Children Reading and Comprehension? (United States)

    Grant, Jamillah M. A.


    Whether electronic books, CD-ROM'S, or interactive media are beneficial in teaching reading should be determined on evidence that they aid reading comprehension. Reading is worthless unless one comprehends. In order to examine the effectiveness of electronic books in a reading program, the characteristics and attributes of how…

  13. Thermoregulatory responses to environmental toxicants: The interaction of thermal stress and toxicant exposure

    International Nuclear Information System (INIS)

    Leon, Lisa R.


    Thermal stress can have a profound impact on the physiological responses that are elicited following environmental toxicant exposure. The efficacy by which toxicants enter the body is directly influenced by thermoregulatory effector responses that are evoked in response to high ambient temperatures. In mammals, the thermoregulatory response to heat stress consists of an increase in skin blood flow and moistening of the skin surface to dissipate core heat to the environment. These physiological responses may exacerbate chemical toxicity due to increased permeability of the skin, which facilitates the cutaneous absorption of many environmental toxicants. The core temperature responses that are elicited in response to high ambient temperatures, toxicant exposure or both can also have a profound impact on the ability of an organism to survive the insult. In small rodents, the thermoregulatory response to thermal stress and many environmental toxicants (such as organophosphate compounds) is often biphasic in nature, consisting initially of a regulated reduction in core temperature (i.e., hypothermia) followed by fever. Hypothermia is an important thermoregulatory survival strategy that is used by small rodents to diminish the effect of severe environmental insults on tissue homeostasis. The protective effect of hypothermia is realized by its effects on chemical toxicity as molecular and cellular processes, such as lipid peroxidation and the formation of reactive oxygen species, are minimized at reduced core temperatures. The beneficial effects of fever are unknown under these conditions. Perspective is provided on the applicability of data obtained in rodent models to the human condition

  14. Basic steps in establishing effective small group teaching sessions in medical schools. (United States)

    Meo, Sultan Ayoub


    Small-group teaching and learning has achieved an admirable position in medical education and has become more popular as a means of encouraging the students in their studies and enhance the process of deep learning. The main characteristics of small group teaching are active involvement of the learners in entire learning cycle and well defined task orientation with achievable specific aims and objectives in a given time period. The essential components in the development of an ideal small group teaching and learning sessions are preliminary considerations at departmental and institutional level including educational strategies, group composition, physical environment, existing resources, diagnosis of the needs, formulation of the objectives and suitable teaching outline. Small group teaching increases the student interest, teamwork ability, retention of knowledge and skills, enhance transfer of concepts to innovative issues, and improve the self-directed learning. It develops self-motivation, investigating the issues, allows the student to test their thinking and higher-order activities. It also facilitates an adult style of learning, acceptance of personal responsibility for own progress. Moreover, it enhances student-faculty and peer-peer interaction, improves communication skills and provides opportunity to share the responsibility and clarify the points of bafflement.

  15. Oxaliplatin-Related Ocular Toxicity

    Directory of Open Access Journals (Sweden)

    Marina Mesquida


    Full Text Available We report the case of a 52-year-old woman with advanced colorectal cancer who was treated with oxaliplatin on a FOLFOX schedule. After 3 cycles of chemotherapy, she started to complain of visual loss, altered color vision and neurological symptoms. Due to the suspicion of ocular and neurological toxicity, antineoplastic treatment was stopped. Her visual field showed a concentric bilateral scotoma and the electrooculogram test revealed severe impairment of the retinal pigment epithelium. Visual acuity, color vision and visual field recovered completely 8 months later, although electrooculogram remained abnormal. Ocular toxicity has been reported as an infrequent adverse event of oxaliplatin. Findings in this case indicate toxicity of this chemotherapeutic agent on the retinal pigment epithelium, which has not been reported before. This damage could be permanent, and it thus differs from previously described oxaliplatin-induced ocular toxicities, which are usually transient and reversible. With increasing use of oxaliplatin as first-line treatment in advanced colorectal cancer, we have to be aware of this possible toxicity.

  16. Recruitment, Selection and Retention: The Shape of the Teaching Force. (United States)

    Schlechty, Phillip C.; Vance, Victor S.

    The characteristics of the talent pool that will be available to the teaching profession is largely controlled by institutions and agencies that either have only a passing interest in the education of teachers (major universities) or by those that have a vested interest in maintaining the status quo (schools of education that are dependent on…

  17. Preparation and characterization of nickel-spiked freshwater sediments for toxicity tests: toward more environmentally realistic nickel partitioning (United States)

    Brumbaugh, William G.; Besser, John M.; Ingersoll, Christopher G.; May, Thomas W.; Ivey, Chris D.; Schlekat, Christian E.; Garman, Emily R.


    Two spiking methods were compared and nickel (Ni) partitioning was evaluated during a series of toxicity tests with 8 different freshwater sediments having a range of physicochemical characteristics. A 2-step spiking approach with immediate pH adjustment by addition of NaOH at a 2:1 molar ratio to the spiked Ni was effective in producing consistent pH and other chemical characteristics across a range of Ni spiking levels. When Ni was spiked into sediment having a high acid-volatile sulfide and organic matter content, a total equilibration period of at least 10 wk was needed to stabilize Ni partitioning. However, highest spiking levels evidently exceeded sediment binding capacities; therefore, a 7-d equilibration in toxicity test chambers and 8 volume-additions/d of aerobic overlying water were used to avoid unrealistic Ni partitioning during toxicity testing. The 7-d pretest equilibration allowed excess spiked Ni and other ions from pH adjustment to diffuse from sediment porewater and promoted development of an environmentally relevant, 0.5- to 1-cm oxic/suboxic sediment layer in the test chambers. Among the 8 different spiked sediments, the logarithm of sediment/porewater distribution coefficient values (log Kd) for Ni during the toxicity tests ranged from 3.5 to 4.5. These Kd values closely match the range of values reported for various field Ni-contaminated sediments, indicating that testing conditions with our spiked sediments were environmentally realistic.

  18. Exploring the impact of toxic attitudes and a toxic environment on the veterinary healthcare team

    Directory of Open Access Journals (Sweden)

    Irene eMoore


    Full Text Available AbstractThe objective of this qualitative study was to compare veterinarians’ and Registered Veterinary Technicians’ (RVT’s perceptions of the veterinary health care team with respect to the impact of toxic attitudes and a toxic environment. Focus group interviews using a semi-structured interview guide and follow up probes were held with 4 veterinarian groups (23 companion animal veterinarians and 4 Registered Veterinary Technician groups (26 RVTs. Thematic analysis of the discussions indicated both veterinarian and RVT participants felt team members with toxic attitudes negatively impacted veterinary team function. These attitudes included people being disrespectful, being resistant to change, always wanting to be the go to person, avoiding conflict, and lacking motivation. When conflict was ignored, or when people with toxic attitudes were not addressed, a toxic environment often resulted. A toxic environment sometimes manifested when broken communication and tension between staff members occurred as a result of employees lacking confidence, skills, or knowledge not being managed properly. It also occurred when employees did not feel appreciated, when there was difficulty coping with turnover, and when there were conflicting demands.The presence of people with a toxic attitude was a source of frustration for both veterinarian and RVT participants. Prompt and consistent attention to negative behaviors is recommended to reduce the development of a toxic environment.

  19. Gulf of Mexico mud toxicity limitations

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, H.E.; Beardmore, D.H. (Phillips Petroleum Co., Bartlesville, OK (USA)); Stewart, W.S. (Drilling Specialties Co. (US))


    Because of the Environmental Protection Agency's recent toxicity limits on drilling mud discharges for offshore Gulf of Mexico, Phillips Petroleum conducted a mud toxicity study based on both field and lab tests. The study, discussed in this article, found the polyanionic cellulose-sulfomethylated quebracho-chrome lignosulfonate mud Phillips had been using would comfortably pass the toxicity limitations. The study also found barite and thinners were of low toxicity, and hydrocarbons and surfactants were highly toxic.

  20. Comparison of Toxicities to Vibrio fischeri and Fish Based on Discrimination of Excess Toxicity from Baseline Level (United States)

    Wang, Xiao H.; Yu, Yang; Huang, Tao; Qin, Wei C.; Su, Li M.; Zhao, Yuan H.


    Investigations on the relationship of toxicities between species play an important role in the understanding of toxic mechanisms to environmental organisms. In this paper, the toxicity data of 949 chemicals to fish and 1470 chemicals to V. fischeri were used to investigate the modes of action (MOAs) between species. The results show that although there is a positive interspecies correlation, the relationship is poor. Analysis on the excess toxicity calculated from toxic ratios (TR) shows that many chemicals have close toxicities and share the same MOAs between the two species. Linear relationships between the toxicities and octanol/water partition coefficient (log KOW) for baseline and less inert compounds indicate that the internal critical concentrations (CBRs) approach a constant both to fish and V. fischeri for neutral hydrophobic compounds. These compounds share the same toxic mechanisms and bio-uptake processes between species. On the other hand, some hydrophilic compounds exhibit different toxic effects with greatly different log TR values between V. fischeri and fish species. These hydrophilic compounds were identified as reactive MOAs to V. fischeri, but not to fish. The interspecies correlation is improved by adding a hydrophobic descriptor into the correlation equation. This indicates that the differences in the toxic ratios between fish and V. fischeri for these hydrophilic compounds can be partly attributed to the differences of bioconcentration between the two species, rather than the differences of reactivity with the target macromolecules. These hydrophilic compounds may more easily pass through the cell membrane of V. fischeri than the gill and skin of fish, react with the target macromolecules and exhibit excess toxicity. The compounds with log KOW > 7 exhibiting very low toxicity (log TR toxicity and MOAs. PMID:26901437

  1. Smartphone: a new device for teaching Physics


    Sans, Jose Angel; Manjón Herrera, Francisco Javier; Cuenca Gotor, Vanesa Paula; Giménez Valentín, Marcos Herminio; Salinas, Isabel; Barreiro Diez, José Antonio; Monsoriu Serra, Juan Antonio; Gómez Tejedor, José Antonio


    [EN] This paper reports on the use of smartphone’s sensors to perform several experiments designed to teach fundamentals of Physics. We have adapted traditional physics laboratory sessions to the use of the different sensors that can be found in a typical smartphone, such as an accelerometer, and light and magnetic field sensors. The existence of a large repository of free AndroidTM and AppleTM applications which exploit the characteristics of these sensors facilitates the design...


    Energy Technology Data Exchange (ETDEWEB)

    Simmons, F


    Reproductive toxicants are a very important class of compounds. They present unique hazards to those of child bearing ages, perform their 'dirty work' using a wide variety of mechanisms on a number of different organs, and are regulatorily important. Because of all of this, properly identifying reproductive toxicants is important, but fraught with difficulty. In this paper we will describe types or reproductive toxicants, their importance, and both mistakes and good practices that people who are not experts in reproductive toxicology may use in their attempts to identify them. Additionally, this paper will focus on chemical reproductive toxicants and will not address biological agents that could affect reproductive toxicity although many principles outlined here could be applied to that endeavor.

  3. Molecular toxicity mechanism of nanosilver

    Directory of Open Access Journals (Sweden)

    Danielle McShan


    Full Text Available Silver is an ancient antibiotic that has found many new uses due to its unique properties on the nanoscale. Due to its presence in many consumer products, the toxicity of nanosilver has become a hot topic. This review summarizes recent advances, particularly the molecular mechanism of nanosilver toxicity. The surface of nanosilver can easily be oxidized by O2 and other molecules in the environmental and biological systems leading to the release of Ag+, a known toxic ion. Therefore, nanosilver toxicity is closely related to the release of Ag+. In fact, it is difficult to determine what portion of the toxicity is from the nano-form and what is from the ionic form. The surface oxidation rate is closely related to the nanosilver surface coating, coexisting molecules, especially thiol-containing compounds, lighting conditions, and the interaction of nanosilver with nucleic acids, lipid molecules, and proteins in a biological system. Nanosilver has been shown to penetrate the cell and become internalized. Thus, nanosilver often acts as a source of Ag+ inside the cell. One of the main mechanisms of toxicity is that it causes oxidative stress through the generation of reactive oxygen species and causes damage to cellular components including DNA damage, activation of antioxidant enzymes, depletion of antioxidant molecules (e.g., glutathione, binding and disabling of proteins, and damage to the cell membrane. Several major questions remain to be answered: (1 the toxic contribution from the ionic form versus the nano-form; (2 key enzymes and signaling pathways responsible for the toxicity; and (3 effect of coexisting molecules on the toxicity and its relationship to surface coating.

  4. Abatement by Naringenin of Doxorubicin-Induced Cardiac Toxicity in Rats

    International Nuclear Information System (INIS)

    Arafa, H.M.; Abd-Ellah, M.F.; Hafez, H.F.


    Doxorubicin is one of the most active cytotoxic agents in current use. It has proven efficacy in various malignancies either alone or combined with other cytocidal agents. The clinical usefulness of the anthracycline drug has been precluded by cardiac toxicity. Many therapeutic interventions have been attempted to improve the therapeutic benefits of the drug. Few, however, have been efficacious in this setting. Purpose: We have addressed in the current study the possible protective effects of naringenin, a flavonoid known to have anti-oxidant properties, on doxorubicin induced cardiac toxicity in male Swiss albino rats. Methods: Forty male Swiss albino rats were used in this study. Naringenin (25 mg/kg body weight) was administered daily by gavage for 7 consecutive days before a cumulative single dose of doxorubicin (15 mg/kg body weight, ip). Doxorubicin induced marked biochemical alterations characteristic of cardiac toxicity including, elevated activities of serum total lactate dehydrogenase (LDH) and creatine phosphokinase (CPK), enhanced lipid peroxidation measured as malonaldehyde (MDA). The anthracycline drug has also reduced the cardiac enzymatic activities of superoxide dismutase (SOD), glutathione-Stransferase (GST) and catalase (CAT). Besides, it reduced significantly the reduced glutathione (GSH) level, but it increased the total NO content in heart tissue. Prior administration of naringenin ahead of doxorubicin challenge ameliorated all these biochemical markers. Taken together, one could conclude that naringenin has a protective role in the abatement of doxorubicin-induced cardiac toxicity that resides, at least in part, on its anti-radical effects and regulatory role on NO production

  5. Predictive QSAR modelling of algal toxicity of ionic liquids and its interspecies correlation with Daphnia toxicity. (United States)

    Roy, Kunal; Das, Rudra Narayan; Popelier, Paul L A


    Predictive toxicology using chemometric tools can be very useful in order to fill the data gaps for ionic liquids (ILs) with limited available experimental toxicity information, in view of their growing industrial uses. Though originally promoted as green chemicals, ILs have now been shown to possess considerable toxicity against different ecological endpoints. Against this background, quantitative structure-activity relationship (QSAR) models have been developed here for the toxicity of ILs against the green algae Scenedesmus vacuolatus using computed descriptors with definite physicochemical meaning. The final models emerged from E-state indices, extended topochemical atom (ETA) indices and quantum topological molecular similarity (QTMS) indices. The developed partial least squares models support the established mechanism of toxicity of ionic liquids in terms of a surfactant action of cations and chaotropic action of anions. The models have been developed within the guidelines of the Organization of Economic Co-operation and Development (OECD) for regulatory QSAR models, and they have been validated both internally and externally using multiple strategies and also tested for applicability domain. A preliminary attempt has also been made, for the first time, to develop interspecies quantitative toxicity-toxicity relationship (QTTR) models for the algal toxicity of ILs with Daphnia toxicity, which should be interesting while predicting toxicity of ILs for an endpoint when the data for the other are available.

  6. UPLC/ESI-QTOF-MS-based metabolomics survey on the toxicity of triptolide and detoxication of licorice. (United States)

    Wang, Zhuo; Liu, Jian-Qun; Xu, Jin-Di; Zhu, He; Kong, Ming; Zhang, Guo-Hua; Duan, Su-Min; Li, Xiu-Yang; Li, Guang-Fu; Liu, Li-Fang; Li, Song-Lin


    Triptolide (TP) from Tripterygium wilfordii has been demonstrated to possess anti-inflammatory, immunosuppressive, and anticancer activities. TP is specially used for the treatment of awkward rheumatoid arthritis, but its clinical application is confined by intense side effects. It is reported that licorice can obviously reduce the toxicity of TP, but the detailed mechanisms involved have not been comprehensively investigated. The current study aimed to explore metabolomics characteristics of the toxic reaction induced by TP and the intervention effect of licorice water extraction (LWE) against such toxicity. Obtained urine samples from control, TP and TP + LWE treated rats were analyzed by UPLC/ESI-QTOF-MS. The metabolic profiles of the control and the TP group were well differentiated by the principal component analysis and orthogonal partial least squares-discriminant analysis. The toxicity of TP was demonstrated to be evolving along with the exposure time of TP. Eight potential biomarkers related to TP toxicity were successfully identified in urine samples. Furthermore, LWE treatment could attenuate the change in six of the eight identified biomarkers. Functional pathway analysis revealed that the alterations in these metabolites were associated with tryptophan, pantothenic acid, and porphyrin metabolism. Therefore, it was concluded that LWE demonstrated interventional effects on TP toxicity through regulation of tryptophan, pantothenic acid, and porphyrin metabolism pathways, which provided novel insights into the possible mechanisms of TP toxicity as well as the potential therapeutic effects of LWE against such toxicity. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  7. Fractionation of fulvic acid by iron and aluminum oxides: influence on copper toxicity to Ceriodaphnia dubia (United States)

    Smith, Kathleen S.; Ranville, James F.; Lesher, Emily K.; Diedrich, Daniel J.; McKnight, Diane M.; Sofield, Ruth M.


    This study examines the effect on aquatic copper toxicity of the chemical fractionation of fulvic acid (FA) that results from its association with iron and aluminum oxyhydroxide precipitates. Fractionated and unfractionated FAs obtained from streamwater and suspended sediment were utilized in acute Cu toxicity tests on ,i>Ceriodaphnia dubia. Toxicity test results with equal FA concentrations (6 mg FA/L) show that the fractionated dissolved FA was 3 times less effective at reducing Cu toxicity (EC50 13 ± 0.6 μg Cu/L) than were the unfractionated dissolved FAs (EC50 39 ± 0.4 and 41 ± 1.2 μg Cu/L). The fractionation is a consequence of preferential sorption of molecules having strong metal-binding (more aromatic) moieties to precipitating Fe- and Al-rich oxyhydroxides, causing the remaining dissolved FA to be depleted in these functional groups. As a result, there is more bioavailable dissolved Cu in the water and hence greater potential for Cu toxicity to aquatic organisms. In predicting Cu toxicity, biotic ligand models (BLMs) take into account dissolved organic carbon (DOC) concentration; however, unless DOC characteristics are accounted for, model predictions can underestimate acute Cu toxicity for water containing fractionated dissolved FA. This may have implications for water-quality criteria in systems containing Fe- and Al-rich sediment, and in mined and mineralized areas in particular. Optical measurements, such as specific ultraviolet absorbance at 254 nm (SUVA254), show promise for use as spectral indicators of DOC chemical fractionation and inferred increased Cu toxicity.

  8. Learning to teach geography for primary education : Results of an experimental programme

    NARCIS (Netherlands)

    Blankman, M.; Schoonenboom, J.; van der Schee, J.; Boogaard, M.; Volman, M.


    Students training to become primary school teachers appear to have little awareness of the core concepts of geography (teaching). To ensure that future primary school teachers are able to develop their pupils’ geographical awareness, a six weeks programme was developed. The characteristics of this

  9. What Research Says about Effective Teaching for Promoting Achievement and Positive Attitudes in Students. An Instructional Module Prepared for Undergraduate Teacher Education in the RAFT Project. (United States)

    Handley, Herbert M., Ed.

    This module, developed by the Research Applications for Teaching (RAFT) project, was written to introduce the preservice teacher to the research base for effective teaching. Particular attention was given to the characteristics of teachers and teaching found in research literature to be associated with achievement and the development of positive…

  10. Institutional traditions in teachers' manners of teaching (United States)

    Lundqvist, Eva; Almqvist, Jonas; Östman, Leif


    The aim of this article is to make a close case study of one teacher's teaching in relation to established traditions within science education in Sweden. The teacher's manner of teaching is analysed with the help of an epistemological move analysis. The moves made by the teacher are then compared in a context of educational philosophy and selective tradition. In the analyses the focus is to study the process of teaching and learning in action in institutionalised and socially shared practices. The empirical material consists of video recordings of four lessons with the same group of students and the same teacher. The students are all in Year 7 in a Swedish 9-year compulsory school. During these lessons the students work with a subject area called "Properties of materials". The results show that the teacher makes a number of different moves with regard to how to proceed and come to a conclusion about what the substances are. Many of these moves are special in that they indicate that the students need to be able to handle the procedural level of school science. These moves do not deal directly with the knowledge production process, but with methodological aspects. The function of the moves turns the students' attention from one source of knowledge to another. The moves are aimed at helping the students to help themselves, since it is through their own activity and their own thinking that learning takes place. This is characteristic in the teacher's manner of teaching. When compared in a context of educational philosophy, this manner of teaching has similarities with progressentialism; a mixture of essentialism and progressivism. This educational philosophy is a central aspect of what is called the academic tradition—a selective tradition common in science education in Sweden between 1960 and 1990.

  11. Effects of various physicochemical characteristics on the toxicities of ZnO and TiO2 nanoparticles toward human lung epithelial cells

    International Nuclear Information System (INIS)

    Hsiao, I-Lun; Huang, Yuh-Jeen


    Although novel nanomaterials are being produced and applied in our daily lives at a rapid pace, related health and environmental toxicity assessments are lagging behind. Recent reports have concluded that the physicochemical properties of nanoparticles (NPs) have a crucial influence on their toxicities and should be evaluated during risk assessments. Nevertheless, several controversies exist regarding the biological effects of NP size and surface area. In addition, relatively few reports describe the extents to which the physicochemical properties of NPs influence their toxicity. In this study, we used six self-synthesized and two commercial ZnO and TiO 2 nanomaterials to evaluate the effects of the major physicochemical properties of NPs (size, shape, surface area, phase, and composition) on human lung epithelium cells (A549). We characterized these NPs using transmission electron microscopy, X-ray diffraction, the Brunauer-Emmett-Teller method, and dynamic laser scattering. From methyl thiazolyl tetrazolium (MTT) and Interleukin 8 (IL-8) assays of both rod- and sphere-like ZnO NPs, we found that smaller NPs had greater toxicity than larger ones-a finding that differs from those of previous studies. Furthermore, at a fixed NP size and surface area, we found that the nanorod ZnO particles were more toxic than the corresponding spherical ones, suggesting that both the size and shape of ZnO NPs influence their cytotoxicity. In terms of the effect of the surface area, we found that the contact area between a single NP and a single cell was more important than the total specific surface area of the NP. All of the TiO 2 NP samples exhibited cytotoxicities lower than those of the ZnO NP samples; among the TiO 2 NPs, the cytotoxicity increased in the following order: amorphous > anatase > anatase/rutile; thus, the phase of the NPs can also play an important role under size-, surface area-, and shape-controlled conditions. - Research Highlights: → Evaluate the

  12. Postoperative high-dose pelvic radiotherapy for N+ prostate cancer: Toxicity and matched case comparison with postoperative prostate bed-only radiotherapy

    International Nuclear Information System (INIS)

    Van Praet, Charles; Ost, Piet; Lumen, Nicolaas; De Meerleer, Gert; Vandecasteele, Katrien; Villeirs, Geert; Decaestecker, Karel; Fonteyne, Valérie


    Purpose: To report on toxicity of postoperative high-dose whole-pelvis radiotherapy (WPRT) with androgen deprivation therapy for lymph node metastasized (N1) prostate cancer (PC). To perform a matched-case analysis to compare this toxicity profile to postoperative prostate bed-only radiotherapy (PBRT). Materials and methods: Forty-eight N1-PC patients were referred for WPRT and 239 node-negative patients for PBRT. Patients were matched 1:1 according to pre-treatment demographics, symptoms, treatment and tumor characteristics. Mean dose to the prostate bed was 75 Gy (WPRT–PBRT) and 54 Gy to the elective nodes (WPRT) in 36 or 37 fractions. End points are genito-urinary (GU) and gastro-intestinal (GI) toxicity. Results: After WPRT, 35% developed grade 2 (G2) and 4% G3 acute GU toxicity. Acute GI toxicity developed in 42% (G2). Late GU toxicity developed in 36% (G2) and 7% (G3). One patient had G4 incontinence. Recuperation occurred in 59%. Late GI toxicity developed in 25% (G2) with 100% recuperation. Incidence of acute and late GI toxicity was higher following WPRT compared to PBRT (p ⩽ 0.041). GU toxicity was similar. With WPRT mean dose to bladder and rectosigmoid were higher. Conclusions: Postoperative high-dose WPRT comes at the cost of a temporary increase in G2. GI toxicity compared to PBRT because larger volumes of rectosigmoid are irradiated

  13. The Teaching Researcher: Faculty Attitudes towards the Teaching and Research Roles (United States)

    Alpay, E.; Verschoor, R.


    Results from a survey on faculty attitudes towards the teaching and research roles are presented. Attention is given to: (i) the perceived value of teaching (and teaching achievements) relative to research, (ii) approaches for research and teaching integration, (iii) the satisfaction gained from typical work tasks, and (iv) the importance of…

  14. Neuro-ophthalmic and clinical characteristics of brain tumours in a ...

    African Journals Online (AJOL)

    Background: Anecdotally, increasing number of patients are seen at Korle Bu Teaching Hospital (KBTH) with brain tumour. Neuro-ophthalmic symptoms and signs may help in timely diagnosis and intervention. Objective: To evaluate the neuro-ophthalmic and clinical characteristics of brain tumour in patients presenting at a ...

  15. Too much of a good thing: a retrospective study of β-lactam concentration-toxicity relationships. (United States)

    Imani, Sahand; Buscher, Hergen; Marriott, Debbie; Gentili, Sheridan; Sandaradura, Indy


    To determine the existence of concentration-toxicity relationships for common β-lactam antibiotic adverse effects and define thresholds above which toxicity is more likely. Retrospective review of consecutive patients treated with piperacillin, meropenem or flucloxacillin who underwent therapeutic drug monitoring (TDM) at St Vincent's Hospital (Sydney, Australia) between January 2013 and December 2015. Adverse events investigated included neurotoxicity, nephrotoxicity, hepatotoxicity and opportunistic Clostridium difficile infection. Toxicity was measured using observational grading criteria, clinical assessment and relevant serum biomarkers. These findings were correlated with trough TDM measurements at the time of toxicity presentation. TDM results from 378 patients (piperacillin = 223, meropenem = 94 and flucloxacillin = 61) were investigated. There was no difference in baseline patient characteristics across antibiotic groups. A statistically significant elevation in mean serum trough concentrations (Cmin) was found in patients diagnosed with neurotoxicity (piperacillin, P 361.4 mg/L; meropenem, Cmin >64.2 mg/L; flucloxacillin, Cmin >125.1 mg/L) or nephrotoxicity (piperacillin, Cmin >452.65 mg/L; meropenem, Cmin >44.45 mg/L) varied across antibiotics. Our data reveal an association between toxic concentrations for a number of β-lactam agents and neurotoxic/nephrotoxic effects. We have defined threshold concentrations above which these toxicities become more likely. Clinicians should balance concerns for therapeutic efficacy with potential toxicity when considering aggressive therapy. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email:

  16. Toxic C17-Sphinganine Analogue Mycotoxin, Contaminating Tunisian Mussels, Causes Flaccid Paralysis in Rodents

    Directory of Open Access Journals (Sweden)

    Riadh Marrouchi


    Full Text Available Severe toxicity was detected in mussels from Bizerte Lagoon (Northern Tunisia using routine mouse bioassays for detecting diarrheic and paralytic toxins not associated to classical phytoplankton blooming. The atypical toxicity was characterized by rapid mouse death. The aim of the present work was to understand the basis of such toxicity. Bioassay-guided chromatographic separation and mass spectrometry were used to detect and characterize the fraction responsible for mussels’ toxicity. Only a C17-sphinganine analog mycotoxin (C17-SAMT, with a molecular mass of 287.289 Da, was found in contaminated shellfish. The doses of C17-SAMT that were lethal to 50% of mice were 750 and 150 μg/kg following intraperitoneal and intracerebroventricular injections, respectively, and 900 μg/kg following oral administration. The macroscopic general aspect of cultures and the morphological characteristics of the strains isolated from mussels revealed that the toxicity episodes were associated to the presence of marine microfungi (Fusarium sp., Aspergillus sp. and Trichoderma sp. in contaminated samples. The major in vivo effect of C17-SAMT on the mouse neuromuscular system was a dose- and time-dependent decrease of compound muscle action potential amplitude and an increased excitability threshold. In vitro, C17-SAMT caused a dose- and time-dependent block of directly- and indirectly-elicited isometric contraction of isolated mouse hemidiaphragms.

  17. Active prey selection in two pelagic copepods feeding on potentially toxic and non-toxic dinoflagellates

    DEFF Research Database (Denmark)

    Schultz, Mette; Kiørboe, Thomas


    Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower but compar......Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower...

  18. Screen-Printed Electrodes Modified with "Green" Metals for Electrochemical Stripping Analysis of Toxic Elements. (United States)

    Economou, Anastasios


    This work reviews the field of screen-printed electrodes (SPEs) modified with "green" metals for electrochemical stripping analysis of toxic elements. Electrochemical stripping analysis has been established as a useful trace analysis technique offering many advantages compared to competing optical techniques. Although mercury has been the preferred electrode material for stripping analysis, the toxicity of mercury and the associated legal requirements in its use and disposal have prompted research towards the development of "green" metals as alternative electrode materials. When combined with the screen-printing technology, such environment-friendly metals can lead to disposable sensors for trace metal analysis with excellent operational characteristics. This review focuses on SPEs modified with Au, Bi, Sb, and Sn for stripping analysis of toxic elements. Different modification approaches (electroplating, bulk modification, use of metal precursors, microengineering techniques) are considered and representative applications are described. A developing related field, namely biosensing based on stripping analysis of metallic nanoprobe labels, is also briefly mentioned.

  19. Research on ERP Teaching Model Reform for Application-Oriented Talents Education (United States)

    Fan, Chongjun; Zhang, Peng; Liu, Qin; Yang, Jianzheng; Xi, Wanyu


    Enterprise Resource Planning is one of the core courses of management. According to the educational characteristics of application-oriented talents training, this paper discussed the issues of ERP teaching for application-oriented talents training at present and proposed a number of ideas and strategies in the aspects of modifying the teaching…

  20. Challenges and Difficulties to Teaching Engineering to Generation Z: a case research


    Barreiro, Suamit Correia; Bozutti, Daniel Fernando


    Many people from generation Z are at the beginning of their academic activities. This generation has peculiar characteristics that might be a challenge in the labor market. Thus, instructors have a great role in their preparation. However, professors might face difficulties dealing with their specific characteristics. The research aims to carry out a general survey to enable an understanding of the greater challenges and difficulties in teaching the subject of engineering to the students of G...

  1. Toxic releases from power plants

    International Nuclear Information System (INIS)

    Rubin, E.S.


    Beginning in 1998, electric power plants burning coal or oil must estimate and report their annual releases of toxic chemicals listed in the Toxics Release Inventory (TRI) published by the US Environmental Protection Agency (EPA). This paper identifies the toxic chemicals of greatest significance for the electric utility sector and develops quantitative estimates of the toxic releases reportable to the TRI for a representative coal-fired power plant. Key factors affecting the magnitude and types of toxic releases for individual power plants also are discussed. A national projection suggests that the magnitude of electric utility industry releases will surpass those of the manufacturing industries which current report to the TRI. Risk communication activities at the community level will be essential to interpret and provide context for the new TRI results

  2. Can dosimetric parameters predict acute hematologic toxicity in rectal cancer patients treated with intensity-modulated pelvic radiotherapy?

    International Nuclear Information System (INIS)

    Wan, Juefeng; Liu, Kaitai; Li, Kaixuan; Li, Guichao; Zhang, Zhen


    To identify dosimetric parameters associated with acute hematologic toxicity (HT) in rectal cancer patients undergoing concurrent chemotherapy and intensity-modulated pelvic radiotherapy. Ninety-three rectal cancer patients receiving concurrent capecitabine and pelvic intensity-modulated radiation therapy (IMRT) were analyzed. Pelvic bone marrow (PBM) was contoured for each patient and divided into three subsites: lumbosacral spine (LSS), ilium, and lower pelvis (LP). The volume of each site receiving 5–40 Gy (V 5, V10, V15, V20, V30, and V40, respectively) as well as patient baseline clinical characteristics was calculated. The endpoint for hematologic toxicity was grade ≥ 2 (HT2+) leukopenia, neutropenia, anemia or thrombocytopenia. Logistic regression was used to analyze correlation between dosimetric parameters and grade ≥ 2 hematologic toxicity. Twenty-four in ninety-three patients experienced grade ≥ 2 hematologic toxicity. Only the dosimetric parameter V40 of lumbosacral spine was correlated with grade ≥ 2 hematologic toxicity. Increased pelvic lumbosacral spine V40 (LSS-V40) was associated with an increased grade ≥ 2 hematologic toxicity (p = 0.041). Patients with LSS-V40 ≥ 60 % had higher rates of grade ≥ 2 hematologic toxicity than did patients with lumbosacral spine V40 < 60 % (38.3 %, 18/47 vs.13 %, 6/46, p =0.005). On univariate and multivariate logistic regression analysis, lumbosacral spine V40 and gender was also the variable associated with grade ≥ 2 hematologic toxicity. Female patients were observed more likely to have grade ≥ 2 hematologic toxicity than male ones (46.9 %, 15/32 vs 14.8 %, 9/61, p =0.001). Lumbosacral spine -V40 was associated with clinically significant grade ≥ 2 hematologic toxicity. Keeping the lumbosacral spine -V40 < 60 % was associated with a 13 % risk of grade ≥ 2 hematologic toxicity in rectal cancer patients undergoing concurrent chemoradiotherapy

  3. Teaching English to Engineers: Between English Language Teaching and Psychology


    Irina-Ana Drobot


    Teaching English to Engineers is part of English for Specific Purposes, a domain which is under the attention of English students especially under the current conditions of finding jobs and establishing partnerships outside Romania. The paper will analyse the existing textbooks together with the teaching strategies they adopt. Teaching English to Engineering students can intersect with domains such as psychology and cultural studies in order to teach them efficiently. Textbooks for students o...

  4. AMAP, the alleged non-toxic isomer of acetaminophen, is toxic in rat and human liver

    NARCIS (Netherlands)

    Hadi, M; Dragovic, S.; van Swelm, R; Herpers, B; van de Water, B.; Russel, RG; Commandeur, J.N.M.; Groothuis, G.M.


    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the wellknown hepatotoxicant acetaminophen (APAP). However, so far, AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in rat

  5. Meta-Teaching: Meaning and Strategy (United States)

    Chen, Xiaoduan


    Meta-teaching is the knowledge and reflection on teaching based on meta-ideas. It is the teaching about teaching, a teaching process with practice consciously guided by thinking, inspiring teachers to teach more effectively. Meta-teaching is related to the knowledge, inspection and amendment of teaching activities in terms of their design,…

  6. Teaching Justice and Teaching Justly: Reflections on Teaching World Religions at a Jesuit Liberal Arts College (United States)

    Schmalz, Mathew N.


    This paper examines how the teaching of world religions at Catholic Christians institutions can contribute to teaching justice and teaching justly. The paper compares central issues engaged by History of Religions as a discipline with those addressed within the Jesuit tradition of higher education as it developed in the wake of the Second Vatican…

  7. Immunological changes following a combined effect of chromic small dose γ-irradiation and toxic agents

    International Nuclear Information System (INIS)

    Shubik, V.M.; Zykova, I.A.


    Immunologic changes under conditions of durable effect of low dose γ-radiation on people in the case of combining radiation with the effect of low concentrations of toxic substances, are studied. Under the above effect, the appearance of deviations from the side of immunologic status is possible. Taking into account the important role of the immunity system in homeostasis preservation and the formation of a series of pathological states it is advisable to use figures, and characteristics inherent in the state of the cell immunity to autoallergic processes to estimate a combined effect of radiation and toxic substances on the organism of people [ru

  8. Toxic Stress: Effects, Prevention and Treatment

    Directory of Open Access Journals (Sweden)

    Hillary A. Franke


    Full Text Available Children who experience early life toxic stress are at risk of long-term adverse health effects that may not manifest until adulthood. This article briefly summarizes the findings in recent studies on toxic stress and childhood adversity following the publication of the American Academy of Pediatrics (AAP Policy Report on the effects of toxic stress. A review of toxic stress and its effects is described, including factors of vulnerability, resilience, and the relaxation response. An integrative approach to the prevention and treatment of toxic stress necessitates individual, community and national focus.

  9. AMAP, the alleged non-toxic isomer of acetaminophen, is toxic in rat and human liver

    NARCIS (Netherlands)

    Hadi, Mackenzie; Dragovic, Sanja; van Swelm, Rachel; Herpers, Bram; van de Water, Bob; Russel, Frans G. M.; Commandeur, Jan N. M.; Groothuis, Geny M. M.

    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the well-known hepatotoxicant acetaminophen (APAP). However, so far, AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in rat

  10. Faculty Members' Views of Effective Teaching: A Case Study of Qatar University (United States)

    Al-Thani, Alanood Mubarak; Al-Meghaissib, Latifa A. Aziz A. A.; Nosair, Mohamed Ragab Abdelhakeem Ali


    Effective teaching (ET) has recently drawn attention within higher educational intuitions owing to the need for greater accountability, and high quality learning outcomes. The present study investigated Qatar University faculty member's (QUFM) perception of ET, characteristics, practices, and impediment, by assembling data from a cluster sample of…

  11. Gender, ethnicity and teaching evaluations : Evidence from mixed teaching teams


    Wagner, Natascha; Rieger, Matthias; Voorvelt, Katherine


    textabstractThis paper studies the effect of teacher gender and ethnicity on student evaluations of teaching quality at university. We analyze a unique data-set featuring mixed teaching teams and a diverse, multicultural, multi-ethnic group of students and teachers. Co-teaching allows us to study the impact of teacher gender and ethnicity on students’ evaluations of teaching exploiting within course variation in an empirical model with course-year fixed effects. We document a negative effect ...

  12. Teaching Business Ethics or Teaching Business Ethically? (United States)

    Stablein, Ralph


    Notes that one of the most important contexts for ethical decision-making is the nature and operation of "contemporary capitalisms." Suggests that rather than issuing a call for teaching business ethics, the author emphasizes the need for more ethical business teaching. (SG)

  13. Leaching characteristics, ecotoxicity, and risk assessment based management of mine wastes (United States)

    Kim, J.; Ju, W. J.; Jho, E. H.; Nam, K.; Hong, J. K.


    Mine wastes generated during mining activities in metal mines generally contain high concentrations of metals that may impose toxic effects to surrounding environment. Thus, it is necessary to properly assess the mining-impacted landscapes for management. The study investigated leaching characteristics, potential environmental effects, and human health risk of mine wastes from three different metal mines in South Korea (molybdenum mine, lead-zinc mine, and magnetite mine). The heavy metal concentrations in the leachates obtained by using the Korean Standard Test Method for Solid Wastes (STM), Toxicity Characteristics Leaching Procedure (TCLP), and Synthetic Precipitation Leaching Procedure (SPLP) met the Korea Waste Control Act and the USEPA region 3 regulatory levels accordingly, even though the mine wastes contained high concentrations of metals. Assuming that the leachates may get into nearby water sources, the leachate toxicity was tested using Daphnia Magna. The toxic unit (TU) values after 24 h and 48 h exposure of all the mine wastes tested met the Korea Allowable Effluent Water Quality Standards (TUwaste may have long-term toxic effects (TU>1 for the eluent at L/S of 30) implying that the long-term effect of mine wastes left in mining areas need to be assessed. Considering reuse of mine wastes as a way of managing mine wastes, the human health risk assessment of reusing the lead-zinc mine waste in industrial areas was carried out using the bioavailable fraction of the heavy metals contained in the mine wastes, which was determined by using the Solubility/Bioavailability Research Consortium method. There may be potential carcinogenic risk (9.7E-05) and non-carcinogenic risk (HI, Hazard Index of 1.0E+00) as CR≧1.0E-05 has carcinogenic risk and HI≧1.0E+00 has non-carcinogenic risk. Overall, this study shows that not only the concentration-based assessment but ecological toxic effect and human health risk based assessments can be utilized for mining

  14. Analysis of Toxic and Non-Toxic Alexandrium (Dinophyceae) Species Using Ribosomal RNA Gene Sequences (United States)


    Therriault, J.-C. (1988). Cladistic analysis of electrophoretic variants within the toxic dinoflagellate genus Protogonyaulax. Botanica Marina 31: 39- 51. 8... Botanica Marina 34: 575-587. Halegraeff, G. M., and Bolch, C.J. (1992). Transport of toxic dinoflagellate cysts via ship’s ballast water: implications...analysis of electrophoretic variants within the toxic dinoflagellate genus Protogonv-u.!a,. Botanica Marina 31: 39-51. Curran, J., Baillie, D.L

  15. Visual advertisements: a tool for English language teaching?

    Directory of Open Access Journals (Sweden)

    Babocká Mária


    Full Text Available Advertising as one of the phenomena of modern times is often an inseparable, though undesirable part of our everyday lives. Current trends indicate that there are still more and more anglicisms, internationalisms, and particles of different cultures penetrating billboard advertisements in many towns and cities around the world, and Slovakia is no exception. The crucial question of this article is: How is it possible to use advertisements in English language teaching and learning? To answer this question, the examination is focused on: (1 defining the role and characteristic traits of advertisements; (2 searching for the linkage between the psychological principles of advertising and psychology of learning foreign languages; (3 the frequency of anglicisms and internationalisms in billboard advertisements in particular areas of selected Slovak cities; (4 concrete suggestions for teaching practice based on the previous findings.

  16. Teaching materials for radiation training and user guides

    International Nuclear Information System (INIS)

    Furuta, Etsuko; Kusama, Keiji


    Training for radiation teaching is important because of understanding radiation. Training methods except for a cloud chamber were proposed in this study; for example, drawing a visual image of a sand-picture by scanning its beta-rays with a handy type GM dosimeter. Though training hours are limited, measurement of alpha-, beta- and gamma-rays is useful to understand important characteristics of radiation. So, useful radioactive materials are the keys of radiation training. Small sizes of radioactive minerals, chemical reagent of KCl and radon progeny in the air were excellent radioactive materials for training. The differences between ionization and excitation of radiation, the relationship between penetration powers of radiation and shield effects of materials, the differences between natural radioactive materials and artificial ones, and other extension lectures were taught usefully for every grade as training by using these teaching materials. (author)

  17. Use of zeolite for removing ammonia and ammonia-caused toxicity in marine toxicity identification evaluations. (United States)

    Burgess, R M; Perron, M M; Cantwell, M G; Ho, K T; Serbst, J R; Pelletier, M C


    Ammonia occurs in marine waters including effluents, receiving waters, and sediment interstitial waters. At sufficiently high concentrations, ammonia can be toxic to aquatic species. Toxicity identification evaluation (TIE) methods provide researchers with tools for identifying aquatic toxicants. For identifying ammonia toxicity, there are several possible methods including pH alteration and volatilization, Ulva lactuca addition, microbial degradation, and zeolite addition. Zeolite addition has been used successfully in freshwater systems to decrease ammonia concentrations and toxicity for several decades. However, zeolite in marine systems has been used less because ions in the seawater interfere with zeolite's ability to adsorb ammonia. The objective of this study was to develop a zeolite method for removing ammonia from marine waters. To accomplish this objective, we performed a series of zeolite slurry and column chromatography studies to determine uptake rate and capacity and to evaluate the effects of salinity and pH on ammonia removal. We also assessed the interaction of zeolite with several toxic metals. Success of the methods was also evaluated by measuring toxicity to two marine species: the mysid Americamysis bahia and the amphipod Ampelisca abdita. Column chromatography proved to be effective at removing a wide range of ammonia concentrations under several experimental conditions. Conversely, the slurry method was inconsistent and variable in its overall performance in removing ammonia and cannot be recommended. The metals copper, lead, and zinc were removed by zeolite in both the slurry and column treatments. The zeolite column was successful in removing ammonia toxicity for both the mysid and the amphipod, whereas the slurry was less effective. This study demonstrated that zeolite column chromatography is a useful tool for conducting marine water TIEs to decrease ammonia concentrations and characterize toxicity.

  18. Transferring methods to teach business administration from one cultural context to another

    Directory of Open Access Journals (Sweden)

    Marie Catalo


    Full Text Available What happens when a teaching method is transferred from one cultural context to another? In this article we investigate this question by looking at how Computer Based Simulations (CBS were transposed from a French context to an Egyptian one. In this article we demonstrate, through the case of Egypt, how culture and the characteristics of the school system impact learning abilities. We describe what happens when Egyptian students are confronted with learning modes they have not encountered prior to University, in the context of an Egyptian-French dual-degree programme in business administration and business informatics. We show that the transfer of CBS as a teaching method revealed cultural differences between French and Egyptian students. As a consequence the teaching objectives of CBS were redefined in order to take the Egyptian context into account.

  19. Prediction of Chest Wall Toxicity From Lung Stereotactic Body Radiotherapy (SBRT)

    Energy Technology Data Exchange (ETDEWEB)

    Stephans, Kevin L., E-mail: [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, OH (United States); Djemil, Toufik; Tendulkar, Rahul D. [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, OH (United States); Robinson, Cliff G. [Department of Radiation Oncology, Siteman Cancer Center, Washington University, St Louis, MO (United States); Reddy, Chandana A.; Videtic, Gregory M.M. [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, OH (United States)


    Purpose: To determine patient, tumor, and treatment factors related to the development of late chest wall toxicity after lung stereotactic body radiotherapy (SBRT). Methods and Materials: We reviewed a registry of 134 patients treated with lung SBRT to 60 Gy in 3 fractions who had greater than 1 year of clinical follow-up and no history of multiple treatments to the same lobe (n = 48). Patients were treated as per Radiation Therapy Oncology Group Protocol 0236 without specific chest wall avoidance criteria. The chest wall was retrospectively contoured. Thirty-two lesions measured less than 3 cm, and sixteen measured 3 to 5 cm. The median planning target volume was 29 cm{sup 3}. Results: With a median follow-up of 18.8 months, 10 patients had late symptomatic chest wall toxicity (4 Grade 1 and 6 Grade 2) at a median of 8.8 months after SBRT. No patient characteristics (age, diabetes, hypertension, peripheral vascular disease, or body mass index) were predictive for toxicity, whereas there was a trend for continued smoking (p = 0.066; odds ratio [OR], 4.4). Greatest single tumor dimension (p = 0.047; OR, 2.63) and planning target volume (p = 0.040; OR, 1.04) were correlated with toxicity, whereas distance from tumor edge to chest wall and gross tumor volume did not reach statistical significance. Volumes of chest wall receiving 30 Gy (V30) through 70 Gy (V70) were all highly significant, although this correlation weakened for V65 and V70 and maximum chest wall point dose only trended to significance (p = 0.06). On multivariate analysis, tumor volume was no longer correlated with toxicity and only V30 through V60 remained statistically significant. Conclusions: Tumor size and chest wall dosimetry are correlated to late chest wall toxicity. Only chest wall V30 through V60 remained significant on multivariate analysis. Restricting V30 to 30 cm{sup 3} or less and V60 to 3 cm{sup 3} or less should result in a 10% to 15% risk of late chest wall toxicity or lower.

  20. Characteristics of Effective EFL Instructors: Language Teachers’ Perceptions Versus Learners’ Perceptions

    Directory of Open Access Journals (Sweden)

    Negar Hajizadeh


    Full Text Available Improving the field of foreign language teaching without improving the qualities of the teachers seems impossible. This attempt, at first hand, requires recognizing the qualities of effective EFL teachers. The aim of this study was to find what foreign language instructors perceive to be the most important characteristics of a successful EFL teacher. In addition, the teachers’ perception was compared to that of learners’ to see whether there were discrepancies between the two groups’ perceptions regarding the preferable characteristics of an effective English language instructors or not. A 58-item questionnaire was administered to teachers at a prominent language institute in Iran. This questionnaire was divided into eight sections and addressed issues relating to teachers’ personal qualities, command in English, teaching methods and evaluation methods they used within the class, mastery over teaching, teacher-student relation, class management and finally language skills management. Teachers were asked to specify the importance of each item in the questionnaire using terms like not important at all, somehow important, important and finally very important. Basic statistics were used to convert the qualitative results into quantitative ones for easier comparison. Interestingly however, the study revealed that the students’ perceptions and teachers’ perceptions do not differ in major ways although there are slight discrepancies.

  1. Development of reflexive critical thinking through the teaching of history in Benguela

    Directory of Open Access Journals (Sweden)

    Âurea Augusto Luís Wafunga


    Full Text Available Critical and reflective thinking is a necessary characteristic of the teacher in the present context. Based on observation and experience as teachers at the Institute of Education Sciences of Benguela, University of Katyavala Buíla, we see that the teaching of history in the Degree in Teaching History contributes little to the development of critical and reflective thinking. This is a very relevant aspect if we consider the need to train good critical and reflective teachers who are able to promote critical thinking in their students in a way that questions the different social contexts. The study presented here consisted in analyzing critical-reflexive thinking through the teaching of history. Non-participant observation and a questionnaire were used for this purpose. The information gathered showed that the respondents point to a low contribution of the teaching of history to the development of critical and reflective thinking. In this way, new methodological strategies need to be adapted in order to promote skills such as: analysis, criticism, reflection, reasoning and understanding of problems in a historical setting.

  2. Bosutinib induced pleural effusions: Case report and review of tyrosine kinase inhibitors induced pulmonary toxicity

    Directory of Open Access Journals (Sweden)

    Natalia I. Moguillansky, MD


    Full Text Available Tyrosine kinase inhibitors are known to cause pulmonary complications. We report a case of bosutinib related bilateral pleural effusions in a patient with chronic myeloid leukemia. Characteristics of the pleural fluid are presented. We also discuss other tyrosine kinase inhibitors induced pulmonary toxicities, including pulmonary hypertension and interstitial lung disease.

  3. The impact of aminated surface ligands and silica shells on the stability, uptake, and toxicity of engineered silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bonventre, Josephine A.; Pryor, Joseph B.; Harper, Bryan J.; Harper, Stacey L., E-mail: [Oregon State University, Department of Environmental and Molecular Toxicology (United States)


    Inherent nanomaterial characteristics, composition, surface chemistry, and primary particle size, are known to impact particle stability, uptake, and toxicity. Nanocomposites challenge our ability to predict nanoparticle reactivity in biological systems if they are composed of materials with contrasting relative toxicities. We hypothesized that toxicity would be dominated by the nanoparticle surface (shell vs core), and that modulating the surface ligands would have a direct impact on uptake. We exposed developing zebrafish (Danio rerio) to a series of ∼70 nm amine-terminated silver nanoparticles with silica shells (AgSi NPs) to investigate the relative influence of surface amination, composition, and size on toxicity. Like-sized aminated AgSi and Si NPs were more toxic than paired hydroxyl-terminated nanoparticles; however, both AgSi NPs were more toxic than the Si NPs, indicating a significant contribution of the silver core to the toxicity. Incremental increases in surface amination did not linearly increase uptake and toxicity, but did have a marked impact on dispersion stability. Mass-based exposure metrics initially supported the hypothesis that smaller nanoparticles (20 nm) would be more toxic than larger particles (70 nm). However, surface area-based metrics revealed that toxicity was independent of size. Our studies suggest that nanoparticle surfaces play a critical role in the uptake and toxicity of AgSi NPs, while the impact of size may be a function of the exposure metric used. Overall, uptake and toxicity can be dramatically altered by small changes in surface functionalization or exposure media. Only after understanding the magnitude of these changes, can we begin to understand the biologically available dose following nanoparticle exposure.

  4. Toxicity of Uranium Adsorbent Materials using the Microtox Toxicity Test

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jiyeon [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jeters, Robert T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, Gary A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bonheyo, George T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    The Marine Sciences Laboratory at the Pacific Northwest National Laboratory evaluated the toxicity of a diverse range of natural and synthetic materials used to extract uranium from seawater. The uranium adsorbent materials are being developed as part of the U. S. Department of Energy, Office of Nuclear Energy, Fuel Resources Program. The goal of this effort was to identify whether deployment of a farm of these materials into the marine environment would have any toxic effects on marine organisms.

  5. Development and Validation of WebQuests in Teaching Epics

    Directory of Open Access Journals (Sweden)

    Ronald Candy Santos Lasaten


    Full Text Available Using the Research Development (R&D methodology, the study aimed to develop and validate WebQuests which can be used in literature subjects, particularly in the tertiary level to address the need of literature teachers for pedagogy in the teaching of epic s. The development of the Web Quests was anchored on the Theory of Constructivism. Two groups of experts validated the Web Quests – the literature experts and the ICT experts. The Content Validation Checklist, used by the literature experts, was utilized t o evaluate the content of the Web Quests. Meanwhile, the Rubric for Evaluating Web Quests, used by the ICT experts, was utilized to evaluate the design characteristics of the Web Quests. Computed weighted means using range interval of point scores were emp loyed to treat the data gathered from the evaluation conducted by both group of experts. The Web Quests developed contain five major parts which include: 1 introduction; 2 task; 3 process; 4 evaluation; and 5 conclusion. Based on the findings, the con tent of the Web Quests developed are valid in terms of objectives, activities and instructional characteristics. Likewise, the design characteristics of the Web Quests are excellent in terms of introductions, tasks, processes, resources, evaluations, concl usions and overall designs. Thus, the Web Quests developed are acceptable and can be utilized as instructional materials by literature teachers in the teaching of epics.

  6. National Air Toxic Assessments (NATA) Results (United States)

    U.S. Environmental Protection Agency — The National Air Toxics Assessment was conducted by EPA in 2002 to assess air toxics emissions in order to identify and prioritize air toxics, emission source types...

  7. Diversity and dynamics of rhizobial populations in acidic soils with aluminum and manganese toxicities in forest zones

    Directory of Open Access Journals (Sweden)

    Linda Manet


    Full Text Available Soil acidity in the humid forest zones of Cameroon is one of the major constraints to agricultural productivity. This study was carried out to assess the rhizobial communities of two acidic soils; with aluminum toxicity (Nkoemvone and manganese toxicity (Nkolbisson for their potential to improve soil fertility in Cameroon. These two soils were used to inoculate to the host plants cowpea and siratro. At harvest, 120 rhizobacterial isolates were extracted from the nodules of these two hosts and subjected to morphological characterization. Twenty isolates per site were selected and analyzed for their 16S rDNA genetic profile following restrictions with endonucleases of PCR products and electrophoresis. The restriction patterns of the 16S rDNA of the 40 isolates showed 12 different profiles. Eight occurred in both types of soils, where as 4 were specific to the manganese-toxic-acidic soil. While the Al toxicity reduced the nodulation and growth of both plants, the Mn toxicity mostly affect the cowpea. This study ascertained the distribution of rhizobia based on soil characteristics. Further molecular analyses would allow the identification of the isolates recovered as well as their phylogenetical relationships.

  8. Stevens–Johnson syndrome and toxic epidermal necrolysis in an academic hospital setting: a 5-year retrospective study

    Directory of Open Access Journals (Sweden)

    Ewa Stocka-Łabno


    Full Text Available Introduction: Toxic epidermal necrolysis and Stevens–Johnson syndrome are acute life-threatening mucocutaneous reactions to drugs. The aims of the study were to identify these drugs and characterize population prone to these reactions. Materials and Methods: Data including demographics, culprit drug, clinical characteristics, course of disease, treatment given, and therapeutic responses were retrospectively collected from medical records of 31 patients admitted to Department of Dermatology from January 2009 to December 2014. Results: Drugs most commonly involved in Stevens–Johnson syndrome were antimicrobials: ciprofloxacin, doxycycline, cefuroxime, trimethoprim, amoxicillin, clindamycin, co-trimoxazole (50% of patients and nonsteroidal anti-inflammatory drugs: ibuprofen, naproxen, metamizole, piroxicam (29% of patients. Drugs involved in toxic epidermal necrolysis were antimicrobials: sulfasalazine, co-trimoxazole, cefuroxime, clindamycin (71% of patients and anticonvulsants: lamotrigine (29% of patients. The comorbidities’ characteristic for the group of patients affected by toxic epidermal necrolysis were psychiatric and autoimmune disorders. The most common complication was infection. Two patients died and in both cases the cause of death was sepsis. Conclusion: The study indicates that in observed population drugs with the highest risk of most severe reactions are lamotrigine (anticonvulsant and antimicrobials (most commonly sulfonamides, therefore it is advisable to consider carefully administration of these drugs, especially to patients with history of autoimmune reactions.

  9. Gender, ethnicity and teaching evaluations : Evidence from mixed teaching teams

    NARCIS (Netherlands)

    N. Wagner (Natascha); M. Rieger (Matthias); K.J. Voorvelt (Katherine)


    textabstractThis paper studies the effect of teacher gender and ethnicity on student evaluations of teaching quality at university. We analyze a unique data-set featuring mixed teaching teams and a diverse, multicultural, multi-ethnic group of students and teachers. Co-teaching allows us to study

  10. Characteristics of High School Students' and Science Teachers' Cognitive Frame about Effective Teaching Method for High School Science Subject (United States)

    Chung, Duk Ho; Park, Kyeong-Jin; Cho, Kyu Seong


    We investigated the cognitive frame of high school students and inservice high school science teachers about effective teaching method, and we also explored how they understood about the teaching methods suggested by the 2009 revised Science Curriculum. Data were collected from 275 high school science teachers and 275 high school students. We analyzed data in terms of the words and the cognitive frame using the Semantic Network Analysis. The results were as follows. First, the teachers perceived that an activity oriented class was the effective science class that helped improve students'' problem-solving abilities and their inquiry skills. The students had the cognitive frame that their teacher had to present relevant and enough teaching materials to students, and that they should also receive assistance from teachers in science class to better prepare for college entrance exam. Second, both students and teachers retained the cognitive frame about the efficient science class that was not reflected 2009 revised Science Curriculum exactly. Especially, neither groups connected the elements of ''convergence'' as well as ''integration'' embedded across science subject areas to their cognitive frame nor cognized the fact that many science learning contents were closed related to one another. Therefore, various professional development opportunities should be offered so that teachers succinctly comprehend the essential features and the intents of the 2009 revised Science Curriculum and thereby implement it in their science lessons effectively. Keywords : semantic network analysis, cognitive frame, teaching method, science lesson


    A time-integrated sampling device interfaced with two toxicity-based assays is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethylsulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor...

  12. Construction of Interactive Teaching System for Course of Mechanical Drawing Based on Mobile Augmented Reality Technology

    Directory of Open Access Journals (Sweden)

    Juan Cheng


    Full Text Available The teaching aim of Mechanical Drawing is to cultivate the students' graphics interpreting ability, plotting ability, inter-space imagination and innovation ability. For engineering students in China Universities, Mechanical Drawing course with the characteristics of 3D and 2D inter-space transformation, is often difficult to master. The ordinary dull teaching method is not enough for stimulating students’ spatial imagination capability, interest in learning, and cannot meet teachers’ teaching needs to explain complicated graphs relationships. In this paper, we design an interactive teaching system based on mobile augmented reality to improve the learning efficiency of Mechanical Drawing course. To check the effect of the proposed system, we carried out a case study of course teaching of Mechanical Drawing. The results demonstrate that the class for which interactive teaching system based on mobile augmented reality technology was adopted is significantly superior to the class for which the ordinary dull teaching approach was adopted with regard to the degree of proficiency of course key and difficult points content,spatial imagination capability, students’ interest in learning and study after class, especially in respect of students’ learning interest and spatial imagination capability.

  13. Selenium species-dependent toxicity, bioavailability and metabolic transformations in Caenorhabditis elegans. (United States)

    Rohn, Isabelle; Marschall, Talke Anu; Kroepfl, Nina; Jensen, Kenneth Bendix; Aschner, Michael; Tuck, Simon; Kuehnelt, Doris; Schwerdtle, Tanja; Bornhorst, Julia


    The essential micronutrient selenium (Se) is required for various systemic functions, but its beneficial range is narrow and overexposure may result in adverse health effects. Additionally, the chemical form of the ingested selenium contributes crucially to its health effects. While small Se species play a major role in Se metabolism, their toxicological effects, bioavailability and metabolic transformations following elevated uptake are poorly understood. Utilizing the tractable invertebrate Caenorhabditis elegans allowed for an alternative approach to study species-specific characteristics of organic and inorganic Se forms in vivo, revealing remarkable species-dependent differences in the toxicity and bioavailability of selenite, selenomethionine (SeMet) and Se-methylselenocysteine (MeSeCys). An inverse relationship was found between toxicity and bioavailability of the Se species, with the organic species displaying a higher bioavailability than the inorganic form, yet being less toxic. Quantitative Se speciation analysis with HPLC/mass spectrometry revealed a partial metabolism of SeMet and MeSeCys. In SeMet exposed worms, identified metabolites were Se-adenosylselenomethionine (AdoSeMet) and Se-adenosylselenohomocysteine (AdoSeHcy), while worms exposed to MeSeCys produced Se-methylselenoglutathione (MeSeGSH) and γ-glutamyl-MeSeCys (γ-Glu-MeSeCys). Moreover, the possible role of the sole selenoprotein in the nematode, thioredoxin reductase-1 (TrxR-1), was studied comparing wildtype and trxr-1 deletion mutants. Although a lower basal Se level was detected in trxr-1 mutants, Se toxicity and bioavailability following acute exposure was indistinguishable from wildtype worms. Altogether, the current study demonstrates the suitability of C. elegans as a model for Se species dependent toxicity and metabolism, while further research is needed to elucidate TrxR-1 function in the nematode.

  14. Changes in soil toxicity by phosphate-aided soil washing: effect of soil characteristics, chemical forms of arsenic, and cations in washing solutions. (United States)

    Jho, Eun Hea; Im, Jinwoo; Yang, Kyung; Kim, Young-Jin; Nam, Kyoungphile


    This study was set to investigate the changes in the toxicity of arsenic (As)-contaminated soils after washing with phosphate solutions. The soil samples collected from two locations (A: rice paddy and B: forest land) of a former smelter site were contaminated with a similar level of As. Soil washing (0.5 M phosphate solution for 2 h) removed 24.5% As, on average, in soil from both locations. Regardless of soil washing, Location A soil toxicities, determined using Microtox, were greater than that of Location B and this could be largely attributed to different soil particle size distribution. With soils from both locations, the changes in As chemical forms resulted in either similar or greater toxicities after washing. This emphasizes the importance of considering ecotoxicological aspects, which are likely to differ depending on soil particle size distribution and changes in As chemical forms, in addition to the total concentration based remedial goals, in producing ecotoxicologically-sound soils for reuse. In addition, calcium phosphate used as the washing solution seemed to contribute more on the toxic effects of the washed soils than potassium phosphate and ammonium phosphate. Therefore, it would be more appropriate to use potassium or ammonium phosphate than calcium phosphate for phosphate-aided soil washing of the As-contaminated soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Promoting addiction medicine teaching through functional mentoring by co-training generalist chief residents with faculty mentors. (United States)

    Alford, Daniel P; Carney, Brittany L; Jackson, Angela H; Brett, Belle; Bridden, Carly; Winter, Michael; Samet, Jeffrey H


    Generalist physicians should play a vital role in identifying and managing individuals with substance use but are inadequately trained to do so. This 5-year (2008-2012) controlled educational study assessed whether internal medicine and family medicine chief residents' (CRs) addiction medicine teaching increased by co-training with faculty mentors at a Chief Resident Immersion Training (CRIT) program in addiction medicine. All CRIT CR attendees identified a residency program faculty mentor to support addiction medicine teaching after CRIT through functional mentoring with a focus on developing and implementing an Addiction Medicine Teaching Project ("Teaching Project"). Approximately half of the CRs attended CRIT with their mentor (co-trained) and half without their mentor (solo-trained). Addiction medicine teaching outcomes were compared between groups using 6- and 11-month questionnaires and 4 bimonthly teaching logs. Of co-trained CRs, mentor characteristics that positively influenced addiction medicine teaching outcomes were identified. One hundred CRs from 74 residency programs attended CRIT from 2008 to 2012; 47 co-trained with their mentors and 53 solo-trained without their mentors. At 6-month follow-up, the co-trained CRs were more likely to meet at least monthly with their mentor (22.7% vs. 9.6%, P mentor as a facilitator for Teaching Project implementation (82.2% vs. 38.5%, P Mentors with more experience, including years of teaching, was associated with better CR Teaching Project outcomes. Co-training generalist chief residents with a faculty mentor appeared to facilitate functional mentoring-driven Teaching Project implementation but did not further increase already high levels of other addiction medicine teaching. Faculty mentors with more years of teaching experience were more effective in facilitating Teaching Project implementation.

  16. Multidisciplinary teaching in swimming: methodological reflection and proposal of check list

    Directory of Open Access Journals (Sweden)

    Sofia Canossa


    Full Text Available The present study proposes a new multidisciplinary approach related to teaching in swimming. Swimming is an interdisciplinary physical activity, which can be truly important at the level of the motor learning and experimentation in aquatic activities. In the present manuscript, it was compared the present reality of teaching in Swimming with a new perspective, this one with a multidisciplinary scope. Following the referred analysis, it was presented a discussion about the orientation and adequacy of the contents of the Swimming curriculum for children and youngsters, which are populations with specific characteristics and development necessities. In this sense, after stating the relevance of a multidisciplinary perspective, it was proposed a new approach for basic aquatic motor skills acquisition based on four disciplines: swimming, water polo, synchronised swimming and platform diving. This was made taking into account the initial stage of swimming teaching, i.e., aquatic readiness. This proposal aims mainly at implementing the teaching of Swimming at a multidisciplinary point of view that, in our opinion, is urgent, namely due to the small expression that the aquatic modalities traditionally considered as swimming satellites (water polo, synchronised swimming and platform diving have in the Portuguese sports context.

  17. Equilibrium leaching of toxic elements from cement stabilized soil. (United States)

    Voglar, Grega E; Leštan, Domen


    The toxicity characteristics leaching procedure (TCLP) is commonly used to assess the efficiency of solidification/stabilization (S/S) of pollutants in wastes, despite recent objections to this method. In this study, formulations of 7, 10, 15 and 20% (w/w) of calcium aluminate cement (CAC) and sulfate resistant Portland cement (SRC) were used for S/S of soil from brownfield contaminated with 43,149, 10,115, 7631, 6130, 90, 82 mg kg(-1) of Zn, Pb, Cu, As, Cd and Ni, respectively. CAC produced S/S soil monoliths of higher mechanical strength (up to 7.65 N mm(-2)). Mass-transfer analysis indicated surface wash-off as a mechanism of toxic elements release, and equilibrium leaching as a crucial parameter of S/S efficiency assessment. In the expected range of field soil pH after S/S (pH 7-9), the TCLP gave markedly different results than the multi-point pH equilibrium leaching method (using nine targeted pH values): up to 2953-, 94-, 483-, 1.3-, 27- and 1.5-times more Zn, Pb, Cu, As, Cd and Ni, respectively, was determined in the TCLP leachate. S/S with CAC reduced leachability of toxic elements more effectively than SRC. Our results indicate that, under given field conditions, the TCLP significantly underrates the efficiency of S/S of contaminated soil with cementitious binders. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Inquiry-based training improves teaching effectiveness of biology teaching assistants (United States)

    Hughes, P. William; Ellefson, Michelle R.


    Graduate teaching assistants (GTAs) are used extensively as undergraduate science lab instructors at universities, yet they often have having minimal instructional training and little is known about effective training methods. This blind randomized control trial study assessed the impact of two training regimens on GTA teaching effectiveness. GTAs teaching undergraduate biology labs (n = 52) completed five hours of training in either inquiry-based learning pedagogy or general instructional “best practices”. GTA teaching effectiveness was evaluated using: (1) a nine-factor student evaluation of educational quality; (2) a six-factor questionnaire for student learning; and (3) course grades. Ratings from both GTAs and undergraduates indicated that indicated that the inquiry-based learning pedagogy training has a positive effect on GTA teaching effectiveness. PMID:24147138

  19. Power Play? Teacher Characteristics and Class Assignments. Working Paper 59 (United States)

    Kalogrides, Demetra; Loeb, Susanna; Beteille, Tara


    While prior research has documented differences in the distribution of teacher characteristics across schools serving different student populations, few studies have examined how teacher sorting occurs within schools. Comparing teachers who teach in the same grade and school in a given year, the authors find less experienced, minority, and female…

  20. Teaching Culture Through Films

    Institute of Scientific and Technical Information of China (English)



    Cultural teaching is an issue which is associated with complexity and paradox and also it is a big challenge for faculty. Teaching culture through films has become an important way of cross-cultural teaching This paper focuses on the reasons for teaching culture through films, the value and how it works. And finally it leads out the prospects of cultural teaching through films.