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Sample records for ps general chemistry

  1. Measuring Student Performance in General Organic Chemistry

    Science.gov (United States)

    Austin, Ara C.; Ben-Daat, Hagit; Zhu, Mary; Atkinson, Robert; Barrows, Nathan; Gould, Ian R.

    2015-01-01

    Student performance in general organic chemistry courses is determined by a wide range of factors including cognitive ability, motivation and cultural capital. Previous work on cognitive factors has tended to focus on specific areas rather than exploring performance across all problem types and cognitive skills. In this study, we have categorized…

  2. Synthesis of Aspirin: A General Chemistry Experiment.

    Science.gov (United States)

    Olmsted, John III

    1998-01-01

    Describes the redesign of the first semester general chemistry laboratory at the college level. An organic component is included in the redesign and it provides students with explicit examples of several types of operations in which chemists engage. Contains 16 references. (DDR)

  3. Understanding Quantum Numbers in General Chemistry Textbooks

    Science.gov (United States)

    Niaz, Mansoor; Fernandez, Ramon

    2008-01-01

    Quantum numbers and electron configurations form an important part of the general chemistry curriculum and textbooks. The objectives of this study are: (1) Elaboration of a framework based on the following aspects: (a) Origin of the quantum hypothesis, (b) Alternative interpretations of quantum mechanics, (c) Differentiation between an orbital and…

  4. Predicting student success in General Chemistry

    Science.gov (United States)

    Figueroa, Daphne Elizabeth

    The goal of this research was to determine the predictors of student success in college level General Chemistry. The potential predictors were categorized as cognitive, non-cognitive, affective, or demographic factors. A broader goal of the study was to provide a reference for academic personnel to better judge the prerequisite skills, knowledge and attitudes that students should attain before enrolling in General Chemistry. Therefore, the study is relevant to chemical educators who are attempting to matriculate candidates for the scientific workforce and to chemical education researches who are interested in student success, student retention and curricular reform. The major hypotheses were that several factors from each category would emerge as significant predictors and that these would differ for students enrolled at three different post-secondary institutions: a community college, a private university and a public university. These hypotheses were tested using multiple regression techniques to analyze grade, student survey and post-test data collected from General Chemistry students at the three institutions. Over-all, twelve factors (six demographic, three cognitive and three affective) emerged as strong, significant predictors of student success. In addition, there were marked differences in which factors emerged based on the type of institution and on how student success was defined. Thus, the major hypotheses of the study were supported. Over-all, this study has significant implications for educational policy, theory, and practice. With regard to policy, there is a need for institutions and departments that offer General Chemistry to provide support for a diverse population of students. And, at the community college level, in particular, there is a need for better academic advising and more institutional support for underprepared students. In the classroom, the professor plays a critical role in influencing students' academic self-concept, which in turn

  5. General Dialdehyde Click Chemistry for Amine Bioconjugation.

    Science.gov (United States)

    Elahipanah, Sina; O'Brien, Paul J; Rogozhnikov, Dmitry; Yousaf, Muhammad N

    2017-05-17

    -conjugation strategy, we designed a straightforward scheme to synthesize a suite of dialdehyde reagents. The dialdehyde molecules were used for applications in cell-surface engineering and for tailoring surfaces for material science applications. We anticipate the broad utility of the general dialdehyde click chemistry to primary amines in all areas of chemical research, ranging from polymers and bioconjugation to material science and nanoscience.

  6. Generalized Subset Designs in Analytical Chemistry.

    Science.gov (United States)

    Surowiec, Izabella; Vikström, Ludvig; Hector, Gustaf; Johansson, Erik; Vikström, Conny; Trygg, Johan

    2017-06-20

    Design of experiments (DOE) is an established methodology in research, development, manufacturing, and production for screening, optimization, and robustness testing. Two-level fractional factorial designs remain the preferred approach due to high information content while keeping the number of experiments low. These types of designs, however, have never been extended to a generalized multilevel reduced design type that would be capable to include both qualitative and quantitative factors. In this Article we describe a novel generalized fractional factorial design. In addition, it also provides complementary and balanced subdesigns analogous to a fold-over in two-level reduced factorial designs. We demonstrate how this design type can be applied with good results in three different applications in analytical chemistry including (a) multivariate calibration using microwave resonance spectroscopy for the determination of water in tablets, (b) stability study in drug product development, and (c) representative sample selection in clinical studies. This demonstrates the potential of generalized fractional factorial designs to be applied in many other areas of analytical chemistry where representative, balanced, and complementary subsets are required, especially when a combination of quantitative and qualitative factors at multiple levels exists.

  7. Cafeteria-Style Grading in General Chemistry

    Science.gov (United States)

    Goodwin, John A.; Gilbert, Brian D.

    2001-04-01

    Self-selected individual course-grade weighting schemes allow students personal choice of course components in the general chemistry sequence at Coastal Carolina University. With the availability of a wide range of commercial and academically produced pedagogical resources, students can select materials that best suit their own learning styles, social situations, and motivation level. Our students use a signed contract to indicate their preferred grade-weighting schemes for determination of the course grade. In doing so, they choose from course components that include peer-led team learning (PLTL) in the Workshop Chemistry (WSC) model, computer-assisted instruction (CAI) using the ChemSkill Builder (CSB) software, a variety of in-class quizzes and group problem-solving exercises, written exams, and the final written exam. Minimum percentage values are required of all components except WSC and CSB, which have been completely optional graded course components at CCU since the summer of 1999. Comparison of student success in the course and content learning suggests that the improvements observed with introduction of a gamut of activities increase even more when the cafeteria-style grading is implemented.

  8. Understanding the Impact of a General Chemistry Course on Students' Transition to Organic Chemistry

    Science.gov (United States)

    Collins-Webb, Alexandra; Jeffery, Kathleen A.; Sweeder, Ryan D.

    2016-01-01

    The move from general chemistry to organic chemistry can be a challenge for students as it often involves a transition from quantitatively-oriented to mechanistically-oriented thinking. This study found that the design of the general chemistry course can change the student experience of this transition as assessed by a reflective survey. The…

  9. Comparing Recent Organizing Templates for Test Content between ACS Exams in General Chemistry and AP Chemistry

    Science.gov (United States)

    Holme, Thomas

    2014-01-01

    Two different versions of "big ideas" rooted content maps have recently been published for general chemistry. As embodied in the content outline from the College Board, one of these maps is designed to guide curriculum development and testing for advanced placement (AP) chemistry. The Anchoring Concepts Content Map for general chemistry…

  10. Stratospheric General Circulation with Chemistry Model (SGCCM)

    Science.gov (United States)

    Rood, Richard B.; Douglass, Anne R.; Geller, Marvin A.; Kaye, Jack A.; Nielsen, J. Eric; Rosenfield, Joan E.; Stolarski, Richard S.

    1990-01-01

    In the past two years constituent transport and chemistry experiments have been performed using both simple single constituent models and more complex reservoir species models. Winds for these experiments have been taken from the data assimilation effort, Stratospheric Data Analysis System (STRATAN).

  11. Using Clinical Cases to Teach General Chemistry

    Science.gov (United States)

    Dewprashad, Brahmadeo; Kosky, Charles; Vaz, Geraldine S.; Martin, Charlotte L.

    2004-01-01

    A clinical study was designed and used to show the relationship of health and medicine, in a typical clinical scenario, where many chemical principles are involved and that an integrated knowledge of chemistry and biology is essential to the understanding, diagnosing and treating of illnesses. A case study would be a positive learning experience…

  12. Avoiding general chemistry textbooks' misrepresentations of ...

    African Journals Online (AJOL)

    It is reported that there is a terminology problem as many authors state that practical equilibrium constants, viz. Kpand Kc, are unit-less quantities. Also, in many chemistry textbooks Kpplays the role of the thermodynamic equilibrium constant, Kº. Thus, after reviewing the proper definition of each of the terms analyzed, one ...

  13. Fluorine Compounds and Dental Health: Applications of General Chemistry Topics

    Science.gov (United States)

    Pinto, Gabriel

    2009-01-01

    An example about the use of everyday phenomena in teaching general chemistry is given. Students have a greater appreciation of the principles of chemistry if they can see the relevance to their lives. Fluorine compounds in dental applications (as topical or as systemic use) provide an excellent context in which to review core content of general…

  14. Connecting Achievement Motivation to Performance in General Chemistry

    Science.gov (United States)

    Ferrell, Brent; Phillips, Michael M.; Barbera, Jack

    2016-01-01

    Student success in chemistry is inherently tied to motivational and other affective processes. We investigated three distinct constructs tied to motivation: self-efficacy, interest, and effort beliefs. These variables were measured twice over the course of a semester in three sections of a first-semester general chemistry course (n = 170). We…

  15. General Chemistry Students' Understanding of Climate Change and the Chemistry Related to Climate Change

    Science.gov (United States)

    Versprille, Ashley N.; Towns, Marcy H.

    2015-01-01

    While much is known about secondary students' perspectives of climate change, rather less is known about undergraduate students' perspectives. The purpose of this study is to investigate general chemistry students' understanding of the chemistry underlying climate change. Findings that emerged from the analysis of the 24 interviews indicate that…

  16. Green Goggles: Designing and Teaching a General Chemistry Course to Nonmajors Using a Green Chemistry Approach

    Science.gov (United States)

    Prescott, Sarah

    2013-01-01

    A novel course using green chemistry as the context to teach general chemistry fundamentals was designed, implemented and is described here. The course design included an active learning approach, with major course graded components including a weekly blog entry, exams, and a semester project that was disseminated by wiki and a public symposium.…

  17. On the Terminological Mistake in the Biography of the Astrakhan Cossack Regiment Commander, Major General P.S. Popov

    Directory of Open Access Journals (Sweden)

    Astafyev Evgeniy V.

    2016-09-01

    Full Text Available On the basis of authentic documents of the late 18th – early 19th centuries, stored in federal and regional archives of Russia, as well as published materials, the article analyzes the reasons of the terminological mistake made in the biography of commander of Astrakhan’s Cossack regiment, major general P.S. Popov, which had been reproduced in the scientific works for longer than 100 years. So well known person in the Lower Volga region, P.S. Popov was purposefully chosen as an object of historical research. His biography is not typical for the people of provincial hereditary Russian nobility of this period, Astrakhan and Saratov’s nobility in this case, where, although rather conventionally, he was linked for a long time in the historical literature. Thanks to the current research, it was determined that P.S. Popov was born in Walachia, evidently not very rich noble family. For a long time he served in Bug Cossack regiment, where got promoted from Arnaut captain to officer rank. He took part in many campaigns of Russian-Turkish war, was repeatedly injured, and distinguished himself during the capture of the fortresses Ochakov and Ismail. P.S. Popov was awarded the order of St. John of Jerusalem, and golden mark for capture of Ismail. P.S. Popov was married to a daughter of Astrakhan priest, and had seven sons and daughters in this spousal. Already serving in Astrakhan province, he purchased a seigneury for himself and descendants in Tsaritsyn district of the Saratov province. His descendants settled in the Lower Volga region, kept the seigneury in possession, served in military and civil services.

  18. General Chemistry Courses That Can Affect Achievement: An Action Research Study in Developing a Plan to Improve Undergraduate Chemistry Courses

    Science.gov (United States)

    Shweikeh, Eman

    2014-01-01

    Over the past 50 years, considerable research has been dedicated to chemistry education. In evaluating principal chemistry courses in higher education, educators have noted the learning process for first-year general chemistry courses may be challenging. The current study investigated perceptions of faculty, students and administrators on…

  19. Attitude Counts: Self-Concept and Success in General Chemistry

    Science.gov (United States)

    Lewis, Scott E.; Shaw, Janet L.; Heitz, Judith O.; Webster, Gail H.

    2009-06-01

    General chemistry is a required first step for students who wish to pursue a career in science or health professions. The course often has low rates of student success and as a result serves as a gateway limiting access to science fields. This study seeks to better understand factors that are related to student success in general chemistry by focusing on the affective domain, in this case students' self-concept, or self-evaluation of ability as it pertains to a specific field of study. First, a profile of students' self-concept in the general chemistry setting is created. Next, the relationship between self-concept and success in the course is investigated, including examining the role of self-concept after taking into account a cognitive measure (SAT scores). This study is unique in that evidence is found for the impact of self-concept after taking into account a cognitive measure. Finally, the effect of a semester-long, inquiry-oriented learning environment on students' self-concept is described. Suggested interventions to improve student self-concept are also discussed.

  20. Improving the Teaching/Learning Process in General Chemistry: Report on the 1997 Stony Brook General Chemistry Teaching Workshop

    Science.gov (United States)

    Hanson, David M.; Wolfskill, Troy

    1998-02-01

    Motivated by the widespread recognition that traditional teaching methods at postsecondary institutions no longer are meeting students' educational needs, 59 participants came to the first Stony Brook General Chemistry Teaching Workshop, July 20-July 25, 1997, on improving the teaching/learning process in General Chemistry. The instructors from 42 institutions across the country, including community colleges, liberal-arts colleges, and large research universities, had mutual concerns that students are having difficulty understanding and applying concepts, finding relevance, transferring knowledge within and across disciplines, and identifying and developing skills needed for success in college and a career. This situation has come about because challenges posed by students' increasing diversity in academic preparation, cultural background, motivation, and career goals go unmet, with too many courses maintaining the conventional objective of structuring and presenting information.

  1. A General Chemistry Laboratory Theme: Spectroscopic Analysis of Aspirin

    Science.gov (United States)

    Byrd, Houston; O'Donnell, Stephen E.

    2003-02-01

    In this paper, we describe the introduction of spectroscopy into the general chemistry laboratory using a series of experiments based on a common substance, aspirin. In the first lab the students synthesize and recrystallize aspirin and take melting points of their product, an aspirin standard, and salicylic acid. The students perform the remaining experiments on a rotating basis where the following four labs run simultaneously: structural characterization of the synthesized aspirin by IR and NMR; analysis of synthesized aspirin and commercial products by UV vis spectroscopy; analysis of synthesized aspirin and commercial products by HPLC; and analysis of calcium in commercial buffered aspirin tablets by AAS. In each of the analysis experiments, students collect, graph, and analyze their data using a spreadsheet. We have found that this series of labs has been very beneficial to our students. From the course evaluations, students indicate that they are beginning to understand how chemistry is applied outside of the classroom.

  2. Impact of General Chemistry on Student Achievement and Progression to Subsequent Chemistry Courses: A Regression Discontinuity Analysis

    Science.gov (United States)

    Shultz, Ginger V.; Gottfried, Amy C.; Winschel, Grace A.

    2015-01-01

    General chemistry is a gateway course that impacts the STEM trajectory of tens of thousands of students each year, and its role in the introductory curriculum as well as its pedagogical design are the center of an ongoing debate. To investigate the role of general chemistry in the curriculum, we report the results of a posthoc analysis of 10 years…

  3. Learning beyond the Classroom: Using Text Messages to Measure General Chemistry Students' Study Habits

    Science.gov (United States)

    Ye, Li; Oueini, Razanne; Dickerson, Austin P.; Lewis, Scott E.

    2015-01-01

    This study used a series of text message inquiries sent to General Chemistry students asking: "Have you studied for General Chemistry I in the past 48 hours? If so, how did you study?" This method for collecting data is novel to chemistry education research so the first research goals were to investigate the feasibility of the technique…

  4. General chemistry courses that can affect achievement: An action research study in developing a plan to improve undergraduate chemistry courses

    Science.gov (United States)

    Shweikeh, Eman

    Over the past 50 years, considerable research has been dedicated to chemistry education. In evaluating principal chemistry courses in higher education, educators have noted the learning process for first-year general chemistry courses may be challenging. The current study investigated perceptions of faculty, students and administrators on chemistry education at three institutions in Southern California. Via action research, the study sought to develop a plan to improve student engagement in general chemistry courses. A mixed method was utilized to analyze different perceptions on key factors determining the level of commitment and engagement in general chemistry education. The approach to chemistry learning from both a faculty and student perspective was examined including good practices, experiences and extent of active participation. The research study considered well-known measures of effective education with an emphasis on two key components: educational practices and student behavior. Institutional culture was inclusively assessed where cognitive expectations of chemistry teaching and learning were communicated. First, the extent in which faculty members are utilizing the "Seven Principles for Good Practice in Undergraduate Education" in their instruction was explored. Second, student attitudes and approaches toward chemistry learning were examined. The focus was on investigating student understanding of the learning process and the structure of chemistry knowledge. The seven categories used to measure students' expectations for learning chemistry were: effort, concepts, math link, reality link, outcome, laboratory, and visualization. This analysis represents the views of 16 faculty and 140 students. The results validated the assertion that students need some competencies and skills to tackle the challenges of the chemistry learning process to deeply engage in learning. A mismatch exists between the expectations of students and those of the faculty

  5. Exploring Dominant Types of Explanations Built by General Chemistry Students

    Science.gov (United States)

    Talanquer, Vicente

    2010-12-01

    The central goal of our study was to explore the nature of the explanations generated by science and engineering majors with basic training in chemistry to account for the colligative properties of solutions. The work was motivated by our broader interest in the characterisation of the dominant types of explanations that science college students use to make sense of phenomena under conditions of limited time and limited explicit knowledge about a topic. Explanations were collected in written form using two different quizzes that students completed under time constraints at the end of a two-semester general chemistry course. Our study revealed that students' ability to generate causal/mechanical explanations depended on the nature of the task. In general, students were more inclined or able to generate mechanistic explanations to account for boiling-point elevation and freezing-point depression than to make sense of osmotic flow. The analysis of the types of causal explanations built by the study participants suggests that students may be biased towards some causal models or explanatory modes characterised as causal-additive and causal-static in our work. A large proportion of the students built non-causal teleological explanations to account for osmotic flow. None of the participants in our study used a dynamic model of matter as the basis for their explanations of any of the relevant phenomena; the idea of an underlying random process that is taking place at all times giving rise to emergent properties and behaviours was completely absent from their intuitive reasoning under conditions of limited time and knowledge.

  6. A New Approach to the General Chemistry Laboratory

    Science.gov (United States)

    Bieron, Joseph F.; McCarthy, Paul J.; Kermis, Thomas W.

    1996-11-01

    Background Canisius College is a medium-sized liberal arts college with a longstanding tradition of maintaining an excellent chemistry program. We realized a few years ago, however, that this tradition was not being sustained by our General Chemistry laboratory course, which had not changed significantly in years. With the help of a grant from the National Science Foundation, our department has been able to design a new laboratory course built around several guiding principles. The design called for experiments to be grouped in units or clusters. Each cluster has a unifying theme or common thread, which gives some coherence to the experiments. The clusters and experiments are listed in the appendix and briefly explained below. Course Design Cluster A's topic is organic and polymer chemistry, and its main objective is to show that chemistry can be enjoyable and relevant to common experiences. Data collection is minimal and hands-on manipulation with observable products is emphasized. Cluster B is a case study of the chemistry of maintaining a swimming pool. The common theme is solution chemistry, and the experiments are designed to promote critical thinking. Cluster C encompasses both oxidation - reduction reactions and electrochemistry, and attempts to show the commonality of these important topics. Cluster D is a series of experiments on methods and techniques of analytical chemistry; in this group the analysis of unknown materials is undertaken. Cluster E is covered last in the second semester, and it stresses important concepts in chemistry at a slightly more advanced level. The emphasis is on the relationship of experiment to theory, and the cluster involves experiments in kinetics, equilibrium, and synthesis. Other guidelines that we considered important in our design were the use of computers (when appropriate), the introduction of microscale chemistry, and the use of instrumentation whenever possible. A separate cluster, labeled Mac, was developed to provide

  7. The Effects of Clickers and Online Homework on Students' Achievement in General Chemistry

    Science.gov (United States)

    Gebru, Misganaw T.

    2012-01-01

    Retention of an introductory general chemistry course material is vital for student success in future chemistry and chemistry-related courses. This study investigated the effects of clickers versus online homework on students' long-term content retention, examined the effectiveness of online homework versus no graded homework on…

  8. Development and Assessment of Green, Research-Based Instructional Materials for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.

    2010-01-01

    This research entails integrating two novel approaches for enriching student learning in chemistry into the context of the general chemistry laboratory. The first is a pedagogical approach based on research in cognitive science and the second is the green chemistry philosophy. Research has shown that inquiry-based approaches are effective in…

  9. Eighth Mendeleyev Congress on General and Applied Chemistry USSR.

    Science.gov (United States)

    1960-06-27

    polymers, organic syntheses, chemical kinetics, radiochemistry, bio- chemistry and metabolic processes, P^t00^.1!^’ r uhvsleal chemistry...interesting paper on »Studies of the Synthesis of Vitamin A, Carotenoids and Other Terpenoids " was presented by G.I. Samokhvalov. N.N

  10. Teaching Lab Report Writing through Inquiry: A Green Chemistry Stoichiometry Experiment for General Chemistry

    Science.gov (United States)

    Cacciatore, Kristen L.; Sevian, Hannah

    2006-01-01

    We present an alternative to a traditional first-year chemistry laboratory experiment. This experiment has four key features: students utilize stoichiometry, learn and apply principles of green chemistry, engage in authentic scientific inquiry, and discover why each part of a scientific lab report is necessary. The importance and essential…

  11. A Transition Program for Underprepared Students in General Chemistry: Diagnosis, Implementation, and Evaluation

    Science.gov (United States)

    Shields, Shawn P.; Hogrebe, Mark C.; Spees, William M.; Handlin, Larry B.; Noelken, Greg P.; Riley, Julie M.; Frey, Regina F.

    2012-01-01

    We developed an online exam to diagnose students who are underprepared for college-level general chemistry and implemented a program to support them during the general chemistry sequence. This transition program consists of extended-length recitations, peer-led team-learning (PLTL) study groups, and peer-mentoring groups. We evaluated this…

  12. Procedimientos de asistencia odontológica hospitalaria en pacientes discapacitados psíquicos no colaboradores tratados con anestesia general

    OpenAIRE

    Hernán Pérez de la Ossa, Tomás

    2016-01-01

    La literatura existente acerca del manejo odontológico de pacientes discapacitados es escasa. El tratamiento de estos pacientes se realiza frecuentemente bajo anestesia general y en un medio hospitalario. La población de discapacitados psíquicos representa un grupo con una alta incidencia de patologías orales. La falta de diagnostico y las diferencias en el tratamiento contribuyen al empeoramiento de su salud oral y justifica la existencia de unidades especificas para estos pacientes...

  13. Performance of Students in General College Chemistry as Related to Secondary School Preparation in Chemistry and Other Selected Variables: A Predictive Study.

    Science.gov (United States)

    Longmire, Marshall Lee

    Investigated were possible relationships between performance in general college chemistry and secondary school preparation in chemistry. The researcher examined achievement in general college chemistry as a possible function of the student's high school science courses, mathematics courses, socioeconomic status, and scores on the ACT tests. Data…

  14. Exploring Dominant Types of Explanations Built by General Chemistry Students

    Science.gov (United States)

    Talanquer, Vicente

    2010-01-01

    The central goal of our study was to explore the nature of the explanations generated by science and engineering majors with basic training in chemistry to account for the colligative properties of solutions. The work was motivated by our broader interest in the characterisation of the dominant types of explanations that science college students…

  15. Eighth Mendeleyev Congress on General and Applied Chemistry - USSR -

    Science.gov (United States)

    1960-07-18

    was prepared, and their insecticidal and toxic properties studied. Acylation of dipterex by organic acids lowers its toxicity for warm-blooded animals...to the development of the new chemistry of ferrocene . Ye. A. Karpeyskaya, A. A. Tovstopyatova and A. A. Balandin (Moscow) showed that rhenium is a very

  16. Atoms-First Curriculum: A Comparison of Student Success in General Chemistry

    Science.gov (United States)

    Esterling, Kevin M.; Bartels, Ludwig

    2013-01-01

    We present an evaluation of the impact of an atoms-first curriculum on student success in introductory chemistry classes and find that initially a lower fraction of students obtain passing grades in the first and second quarters of the general chemistry series. This effect is more than reversed for first-quarter students after one year of…

  17. Examining the Effects of Reflective Journals on Pre-Service Science Teachers' General Chemistry Laboratory Achievement

    Science.gov (United States)

    Cengiz, Canan; Karatas, Faik Özgür

    2015-01-01

    The general chemistry laboratory is an appropriate place for learning chemistry well. It is also effective for stimulating higher-order thinking skills, including reflective thinking, a skill that is crucial for science teaching as well as learning. This study aims to examine the effects of feedback-supported reflective journal-keeping activities…

  18. Based on a True Story: Using Movies as Source Material for General Chemistry Reports

    Science.gov (United States)

    Griep, Mark A.; Mikasen, Marjorie L.

    2005-01-01

    The story to improve student enthusiasm for writing reports about the chemistry behind events reported in the news and movies were chosen as the source material. The use of movies in the chemical classroom helps an instructor move the subject of chemistry from abstract, general themes to the personal and subjective arena of human interactions.

  19. Student Conceptions about Energy Transformations: Progression from General Chemistry to Biochemistry

    Science.gov (United States)

    Wolfson, Adele J.; Rowland, Susan L.; Lawrie, Gwendolyn A.; Wright, Anthony H.

    2014-01-01

    Students commencing studies in biochemistry must transfer and build on concepts they learned in chemistry and biology classes. It is well established, however, that students have difficulties in transferring critical concepts from general chemistry courses; one key concept is "energy." Most previous work on students' conception of energy…

  20. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    Science.gov (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  1. The ACS Exams Institute Undergraduate Chemistry Anchoring Concepts Content Map I: General Chemistry

    Science.gov (United States)

    Holme, Thomas; Murphy, Kristen

    2012-01-01

    To provide tools for programmatic assessment related to the use of ACS Exams in undergraduate chemistry courses, the ACS Exams Institute has built a content map that applies to the entire undergraduate curriculum. At the top two levels, the grain size of the content classification is large and spans the entire undergraduate curriculum. At the…

  2. Chemistry for DUMMIES: how to popularize and introduce chemistry to the general public.

    Science.gov (United States)

    Montangero, Marc

    2012-01-01

    To mark the occasion of the International Year of Chemistry, each week in 2011 I posted a two-minute film demonstrating and explaining a simple and safe experiment to be carried out at home using everyday household products on the site www.chimie.ch/nuls.

  3. A general approach for monodisperse colloidal perovskites, Chemistry of Materials

    NARCIS (Netherlands)

    Demirors, A.F.; Imhof, A.

    2009-01-01

    We describe a novel general method for synthesizing monodisperse colloidal perovskite particles at room temperature by postsynthesis addition of metal hydroxides to amorphous titania colloids. In previous work, we used titania particles to synthesize homogenously mixed silica-titania composite

  4. Computer-based, Jeopardy™-like game in general chemistry for engineering majors

    Science.gov (United States)

    Ling, S. S.; Saffre, F.; Kadadha, M.; Gater, D. L.; Isakovic, A. F.

    2013-03-01

    We report on the design of Jeopardy™-like computer game for enhancement of learning of general chemistry for engineering majors. While we examine several parameters of student achievement and attitude, our primary concern is addressing the motivation of students, which tends to be low in a traditionally run chemistry lectures. The effect of the game-playing is tested by comparing paper-based game quiz, which constitutes a control group, and computer-based game quiz, constituting a treatment group. Computer-based game quizzes are Java™-based applications that students run once a week in the second part of the last lecture of the week. Overall effectiveness of the semester-long program is measured through pretest-postest conceptual testing of general chemistry. The objective of this research is to determine to what extent this ``gamification'' of the course delivery and course evaluation processes may be beneficial to the undergraduates' learning of science in general, and chemistry in particular. We present data addressing gender-specific difference in performance, as well as background (pre-college) level of general science and chemistry preparation. We outline the plan how to extend such approach to general physics courses and to modern science driven electives, and we offer live, in-lectures examples of our computer gaming experience. We acknowledge support from Khalifa University, Abu Dhabi

  5. Investigations of nitrogen oxide plasmas: Fundamental chemistry and surface reactivity and monitoring student perceptions in a general chemistry recitation

    Science.gov (United States)

    Blechle, Joshua M.

    unparalleled insight into the chemistry of these plasma systems. Part II of this work is focused on understanding the efficacy of a general chemistry recitation program. Such programs can be an valuable tool for improving students' problem solving skills and understanding using methods that are difficult to implement in large lecture settings. Here, general chemistry students at Colorado State University participated in a variety of recitation activities throughout the first semester of a 2-semester general chemistry sequence, including peer-led exercises, games, and scaffolded worksheets. Through weekly surveys, students were asked to evaluate and assess recitation activities for both interest and effectiveness as part of their course homework. Also included in these survey assignments were content questions relevant to the weekly themes, providing a measure of student learning of recitation topics. Student opinions were correlated with content retention, and these data were compared against student responses to a pre-survey administered before the first recitation session. This analysis allows for monitoring students' expectations of recitation courses and how well those expectations are met through the various types of activities employed. Ultimately, this work has found that students have positive feeling with respect to individual assignments, but that perspectives on chemistry and the course in general decrease dramatically from the beginning to the end of the semester. Thus, this work can serve as a significant starting points for future efforts to monitor and record student perceptions in the general chemistry recitation classroom, leading to further investigation into the source of changing attitudes and the role that week-to-week activities have on global course attitudes.

  6. General Procedure for the Easy Calculation of pH in an Introductory Course of General or Analytical Chemistry

    Science.gov (United States)

    Cepriá, Gemma; Salvatella, Luis

    2014-01-01

    All pH calculations for simple acid-base systems used in introductory courses on general or analytical chemistry can be carried out by using a general procedure requiring the use of predominance diagrams. In particular, the pH is calculated as the sum of an independent term equaling the average pK[subscript a] values of the acids involved in the…

  7. A General Chemistry and Precalculus First-Year Interest Group (FIG): Effect on Retention, Skills, and Attitudes

    Science.gov (United States)

    Pence, Laura E.; Workman, Harry J.; Haruta, Mako E.

    2005-01-01

    The backdrop of the calculus reform movement created a fertile movement for the creation of overlap between general chemistry and precalculus as many of the goals emphasized key concepts from the chemistry lab. By using the graphing calculator in both precalculus and chemistry laboratory enhanced the students' comfort and competence with the…

  8. Development, Implementation, and Assessment of General Chemistry Lab Experiments Performed in the Virtual World of Second Life

    Science.gov (United States)

    Winkelmann, Kurt; Keeney-Kennicutt, Wendy; Fowler, Debra; Macik, Maria

    2017-01-01

    Virtual worlds are a potential medium for teaching college-level chemistry laboratory courses. To determine the feasibility of conducting chemistry experiments in such an environment, undergraduate students performed two experiments in the immersive virtual world of Second Life (SL) as part of their regular General Chemistry 2 laboratory course.…

  9. What We Don't Test: What an Analysis of Unreleased ACS Exam Items Reveals about Content Coverage in General Chemistry Assessments

    Science.gov (United States)

    Reed, Jessica J.; Villafan~e, Sachel M.; Raker, Jeffrey R.; Holme, Thomas A.; Murphy, Kristen L.

    2017-01-01

    General chemistry courses are often the foundation for the study of other science disciplines and upper-level chemistry concepts. Students who take introductory chemistry courses are more often from health and science-related fields than chemistry. As such, the content taught and assessed in general chemistry courses is envisioned as building…

  10. Effects of Implementing a Hybrid Wet Lab and Online Module Lab Curriculum into a General Chemistry Course: Impacts on Student Performance and Engagement with the Chemistry Triplet

    Science.gov (United States)

    Irby, Stefan M.; Borda, Emily J.; Haupt, Justin

    2018-01-01

    Here, we describe the implementation a hybrid general chemistry teaching laboratory curriculum that replaces a portion of a course's traditional "wet lab" experiences with online virtual lab modules. These modules intentionally utilize representations on all three levels of the chemistry triplet-macroscopic, submicroscopic, and symbolic.…

  11. Design, Development, and Psychometric Analysis of a General, Organic, and Biological Chemistry Topic Inventory Based on the Identified Main Chemistry Topics Relevant to Nursing Clinical Practice

    Science.gov (United States)

    Brown, Corina E.

    2013-01-01

    This two-stage study focused on the undergraduate nursing course that covers topics in general, organic, and biological (GOB) chemistry. In the first stage, the central objective was to identify the main concepts of GOB chemistry relevant to the clinical practice of nursing. The collection of data was based on open-ended interviews of both nursing…

  12. Results of an interactively coupled atmospheric chemistrygeneral circulation model: Comparison with observations

    Directory of Open Access Journals (Sweden)

    R. Hein

    Full Text Available The coupled climate-chemistry model ECHAM4.L39(DLR/CHEM is presented which enables a simultaneous treatment of meteorology and atmospheric chemistry and their feedbacks. This is the first model which interactively combines a general circulation model with a chemical model, employing most of the important reactions and species necessary to describe the stratospheric and upper tropospheric ozone chemistry, and which is computationally fast enough to allow long-term integrations with currently available computer resources. This is possible as the model time-step used for the chemistry can be chosen as large as the integration time-step for the dynamics. Vertically the atmosphere is discretized by 39 levels from the surface up to the top layer which is centred at 10 hPa, with a relatively high vertical resolution of approximately 700 m near the extra-tropical tropopause. We present the results of a control simulation representing recent conditions (1990 and compare it to available observations. The focus is on investigations of stratospheric dynamics and chemistry relevant to describe the stratospheric ozone layer. ECHAM4.L39(DLR/CHEM reproduces main features of stratospheric dynamics in the arctic vortex region, including stratospheric warming events. This constitutes a major improvement compared to earlier model versions. However, apparent shortcomings in Antarctic circulation and temperatures persist. The seasonal and interannual variability of the ozone layer is simulated in accordance with observations. Activation and deactivation of chlorine in the polar stratospheric vortices and their inter-hemispheric differences are reproduced. Considering methane oxidation as part of the dynamic-chemistry feedback results in an improved representation of the spatial distribution of stratospheric water vapour concentrations. The current model constitutes a powerful tool to investigate, for instance, the combined direct and indirect effects of anthropogenic

  13. An Investigation of Online and Face-to-Face Communication in General Chemistry

    Science.gov (United States)

    Weaver, Gabriela; Green, Kellie; Rahman, Aliyah; Epp, Erik

    2009-01-01

    This exploratory study investigated an online office hour and a face-to-face recitation for similarities and differences. The online office hour and face-to-face recitation were a part of general chemistry courses taught at different universities. The courses covered the same material at the same level. The results of the investigation revealed…

  14. Playing with Light: Adventures in Optics and Spectroscopy for Honors and Majors General Chemistry

    Science.gov (United States)

    van Staveren, Marie N.; Edwards, Kimberly D.; Apkarian, V. A.

    2012-01-01

    A lab was developed for use in an undergraduate honors and majors general chemistry laboratory to introduce students to optics, spectroscopy, and the underlying principles of quantum mechanics. This lab includes four mini-experiments exploring total internal reflection, the tunneling of light, spectra of sparklers and colored candles, and emission…

  15. Teaching Assistants' Perceptions of a Training to Support an Inquiry-Based General Chemistry Laboratory Course

    Science.gov (United States)

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Whitworth, Brooke A.

    2015-01-01

    The purpose of this qualitative investigation was to better understand teaching assistants' (TAs') perceptions of training in a guided inquiry undergraduate general chemistry laboratory context. The training was developed using existing TA training literature and informed by situated learning theory. TAs engaged in training prior to teaching (~25…

  16. General Chemistry Students' Conceptual Understanding and Language Fluency: Acid-Base Neutralization and Conductometry

    Science.gov (United States)

    Nyachwaya, James M.

    2016-01-01

    The objective of this study was to examine college general chemistry students' conceptual understanding and language fluency in the context of the topic of acids and bases. 115 students worked in groups of 2-4 to complete an activity on conductometry, where they were given a scenario in which a titration of sodium hydroxide solution and dilute…

  17. Team-Based Learning Reduces Attrition in a First-Semester General Chemistry Course

    Science.gov (United States)

    Comeford, Lorrie

    2016-01-01

    Team-based learning (TBL) is an instructional method that has been shown to reduce attrition and increase student learning in a number of disciplines. TBL was implemented in a first-semester general chemistry course, and its effect on attrition was assessed. Attrition from sections before implementing TBL (fall 2008 to fall 2009) was compared with…

  18. Inquiry-Based Arson Investigation for General Chemistry Using GC-MS

    Science.gov (United States)

    Maurer, Marta K.; Bukowski, Michael R.; Menachery, Mary D.; Zatorsky, Adam R.

    2010-01-01

    We have developed a two-week guided-inquiry laboratory in which first-semester general chemistry students investigate a suspected arson using gas chromatography--mass spectrometry and paper chromatography. In the process of evaluating evidence from the crime scene, students develop and test hypotheses and learn the fundamentals of chromatography,…

  19. Examination of Bond Properties through Infrared Spectroscopy and Molecular Modeling in the General Chemistry Laboratory

    Science.gov (United States)

    Csizmar, Clifford M.; Force, Dee Ann; Warner, Don L.

    2012-01-01

    A concerted effort has been made to increase the opportunities for undergraduate students to address scientific problems employing the processes used by practicing chemists. As part of this effort, an infrared (IR) spectroscopy and molecular modeling experiment was developed for the first-year general chemistry laboratory course. In the…

  20. Looking beyond Lewis Structures: A General Chemistry Molecular Modeling Experiment Focusing on Physical Properties and Geometry

    Science.gov (United States)

    Linenberger, Kimberly J.; Cole, Renee S.; Sarkar, Somnath

    2011-01-01

    We present a guided-inquiry experiment using Spartan Student Version, ready to be adapted and implemented into a general chemistry laboratory course. The experiment provides students an experience with Spartan Molecular Modeling software while discovering the relationships between the structure and properties of molecules. Topics discussed within…

  1. Supporting Students' Learning to Learn in General Chemistry Using Moodle

    Science.gov (United States)

    Gonza´lez, Maritza Lau; Haza, Ulises Ja´uregui; Gramagtes, Aurora Pe´rez; Leo´n, Gloria Farin~as; Le Bolay, Nadine

    2014-01-01

    A combination of regular classroom teaching with the use of resources available on the Moodle platform has been designed to foster the development of skills for learning to learn for students in an undergraduate general chemistry course. The use of the Moodle platform essentially aimed at strengthening the students' prior knowledge of…

  2. Effects and Implications of Mini-Lectures on Learning in First-Semester General Chemistry

    Science.gov (United States)

    Toto, Joe; Booth, Kathy

    2008-01-01

    This study describes the efficacy of a novel tool, mini-lecture movies, in teaching Web based general chemistry. The analysis shows a marked improvement in student learning, as evidenced by a corresponding increase in homework and final exam scores. Students with access to mini-lecture movies scored 11.2% (p = 0.016) higher than students who did…

  3. Structure Determination of Unknown Organic Liquids Using NMR and IR Spectroscopy: A General Chemistry Laboratory

    Science.gov (United States)

    Pavel, John T.; Hyde, Erin C.; Bruch, Martha D.

    2012-01-01

    This experiment introduced general chemistry students to the basic concepts of organic structures and to the power of spectroscopic methods for structure determination. Students employed a combination of IR and NMR spectroscopy to perform de novo structure determination of unknown alcohols, without being provided with a list of possible…

  4. Reform in a General Chemistry Laboratory: How Do Students Experience Change in the Instructional Approach?

    Science.gov (United States)

    Chopra, I.; O'Connor, J.; Pancho, R.; Chrzanowski, M.; Sandi-Urena, S.

    2017-01-01

    This qualitative study investigated the experience of a cohort of students exposed consecutively to two substantially different environments in their General Chemistry Laboratory programme. To this end, the first semester in a traditional expository programme was followed by a semester in a cooperative, problem-based, multi-week format. The focus…

  5. A Genetically Optimized Predictive System for Success in General Chemistry Using a Diagnostic Algebra Test

    Science.gov (United States)

    Cooper, Cameron I.; Pearson, Paul T.

    2012-01-01

    In higher education, many high-enrollment introductory courses have evolved into "gatekeeper" courses due to their high failure rates. These courses prevent many students from attaining their educational goals and often become graduation roadblocks. At the authors' home institution, general chemistry has become a gatekeeper course in which…

  6. Web-Enhanced General Chemistry Increases Student Completion Rates, Success, and Satisfaction

    Science.gov (United States)

    Amaral, Katie E.; Shank, John D.; Shibley, Ivan A., Jr.; Shibley, Lisa R.

    2013-01-01

    General Chemistry I historically had one of the highest failure and withdrawal rates at Penn State Berks, a four-year college within the Penn State system. The course was completely redesigned to incorporate more group work, the use of classroom response systems, peer mentors, and a stronger online presence via the learning management system…

  7. Exploring Chemical Equilibrium with Poker Chips: A General Chemistry Laboratory Exercise

    Science.gov (United States)

    Bindel, Thomas H.

    2012-01-01

    A hands-on laboratory exercise at the general chemistry level introduces students to chemical equilibrium through a simulation that uses poker chips and rate equations. More specifically, the exercise allows students to explore reaction tables, dynamic chemical equilibrium, equilibrium constant expressions, and the equilibrium constant based on…

  8. Assessment of Antioxidant Capacities in Foods: A Research Experience for General Chemistry Students

    Science.gov (United States)

    Hoch, Matthew A.; Russell, Cianan B.; Steffen, Debora M.; Weaver, Gabriela C.; Burgess, John R.

    2009-01-01

    With the booming interest in health food and nutrition, investigations of the antioxidant capacities of various foods have come to the forefront of food science. This general chemistry laboratory curriculum provides students with an opportunity to design and implement their own experiments relating to antioxidants in food. The curriculum is six…

  9. Selected chapters from general chemistry in physics teaching with the help of e - learning

    Science.gov (United States)

    Feszterová, Melánia

    2017-01-01

    Education in the field of natural disciplines - Mathematics, Physics, Chemistry, Ecology and Biology takes part in general education at all schools on the territory of Slovakia. Its aim is to reach the state of balanced development of all personal characteristics of pupils, to teach them correctly identify and analyse problems, propose solutions and above all how to solve the problem itself. High quality education can be reached only through the pedagogues who have a good expertise knowledge, practical experience and high level of pedagogical abilities. The teacher as a disseminator of natural-scientific knowledge should be not only well-informed about modern tendencies in the field, but he/she also should actively participate in project tasks This is the reason why students of 1st year of study (bachelor degree) at the Department of Physics of Constantine the Philosopher University in Nitra attend lectures in the frame of subject General Chemistry. In this paper we present and describe an e - learning course called General Chemistry that is freely accessible to students. One of the aims of this course is to attract attention towards the importance of cross-curricular approach which seems to be fundamental in contemporary natural-scientific education (e.g. between Physics and Chemistry). This is why it is so important to implement a set of new topics and tasks that support development of abilities to realise cross-curricular goals into the process of preparation of future teachers of Physics.

  10. Chemistry?!

    Indian Academy of Sciences (India)

    Chemistry is the science of matter and of its transformations, and life is its highest expression. It provides structures endowed with properties and develops processes for the synthesis of structures. It plays a primordial role in our understanding of material phe- nomena, in our capability to act upon them, to modify them, to.

  11. Investigating macroscopic, submicroscopic, and symbolic connections in a college-level general chemistry laboratory

    Science.gov (United States)

    Thadison, Felicia Culver

    Explanations of chemical phenomena rely on understanding the behavior of submicroscopic particles. Because this level is "invisible," it is described using symbols such as models, diagrams and equations. For this reason, students often view chemistry as a "difficult" subject. The laboratory offers a unique opportunity for the students to experience chemistry macroscopically as well as symbolically. The purpose of this investigation was to determine how chemistry lab students explained chemical phenomenon on the macroscopic, submicroscopic, and representational/symbolic level. The participants were undergraduate students enrolled in an introductory level general chemistry lab course. Students' background information (gender, the number of previous chemistry courses), scores on final exams, and final average for the course were collected. Johnstone's triangle of representation guided the design and implementation of this study. A semi-structured interview was also conducted to bring out student explanations. The questionnaires required students to draw a molecule of water, complete acid base reaction equations, represent, submicroscopically, the four stages of an acid-base titration, and provide definitions of various terms. Students were able represent the submicroscopic level of water. Students were not able to represent the submicroscopic level of the reaction between an acid and a base. Students were able to represent the macroscopic level of an acid base reaction. Students were able to symbolically represent the reaction of an acid and a base. These findings indicate that students can use all three levels of chemical representation. However, students showed an inability to connect the levels in relation to acid-base chemistry. There was no relationship between a student's ability to use the levels and his or her final score in the course.

  12. An NMR-Smell Module for the First-Semester General Chemistry Laboratory

    Science.gov (United States)

    Uffelman, Erich S.; Cox, Elizabeth H.; Brown Goehring, J.; Lorig, Tyler S.; Davis, C. Michele

    2003-12-01

    This article describes a module of NMR-smell experiments for the general chemistry laboratory that can be taught in two-week or three-week formats; the module has also been run in a modified form with high school students during the summer. The series of experiments involves an exploration of organic stereochemistry via hands-on model building, several chemosensory smell tests, and hands-on use of 13C NMR, thus serving as a powerful interdisciplinary lab involving chemistry, physics, and neuroscience. Similarities and differences between NMR and MRI methods are emphasized. By the end of the NMR-smell module, students have a very basic knowledge of the physics of the NMR process, the ability to identify different types of organic isomerism, the ability to identify stereogenic centers in molecules, and a basic knowledge of the importance of 3-D structure in chemistry. The less quantifiable, but in some ways more important, benefits of the module that students really appreciate are getting to "touch and play" with the NMR, running the smell tests and seeing the strengths and limitations of their noses as analytical instruments, and seeing how the basic chemistry and physics of NMR relate to MRI.

  13. The Role of Water Chemistry in Marine Aquarium Design: A Model System for a General Chemistry Class

    Science.gov (United States)

    Keaffaber, Jeffrey J.; Palma, Ramiro; Williams, Kathryn R.

    2008-01-01

    Water chemistry is central to aquarium design, and it provides many potential applications for discussion in undergraduate chemistry and engineering courses. Marine aquaria and their life support systems feature many chemical processes. A life support system consists of the entire recirculation system, as well as the habitat tank and all ancillary…

  14. Results of an interactively coupled atmospheric chemistry - general circulation model. Comparison with observations

    Energy Technology Data Exchange (ETDEWEB)

    Hein, R.; Dameris, M.; Schnadt, C. [and others

    2000-01-01

    An interactively coupled climate-chemistry model which enables a simultaneous treatment of meteorology and atmospheric chemistry and their feedbacks is presented. This is the first model, which interactively combines a general circulation model based on primitive equations with a rather complex model of stratospheric and tropospheric chemistry, and which is computational efficient enough to allow long-term integrations with currently available computer resources. The applied model version extends from the Earth's surface up to 10 hPa with a relatively high number (39) of vertical levels. We present the results of a present-day (1990) simulation and compare it to available observations. We focus on stratospheric dynamics and chemistry relevant to describe the stratospheric ozone layer. The current model version ECHAM4.L39(DLR)/CHEM can realistically reproduce stratospheric dynamics in the Arctic vortex region, including stratospheric warming events. This constitutes a major improvement compared to formerly applied model versions. However, apparent shortcomings in Antarctic circulation and temperatures persist. The seasonal and interannual variability of the ozone layer is simulated in accordance with observations. Activation and deactivation of chlorine in the polar stratospheric vortices and their interhemispheric differences are reproduced. The consideration of the chemistry feedback on dynamics results in an improved representation of the spatial distribution of stratospheric water vapor concentrations, i.e., the simulated meriodional water vapor gradient in the stratosphere is realistic. The present model version constitutes a powerful tool to investigate, for instance, the combined direct and indirect effects of anthropogenic trace gas emissions, and the future evolution of the ozone layer. (orig.)

  15. Why has the bohr-sommerfeld model of the atom been ignoredby general chemistry textbooks?

    Science.gov (United States)

    Niaz, Mansoor; Cardellini, Liberato

    2011-12-01

    Bohr's model of the atom is considered to be important by general chemistry textbooks. A major shortcoming of this model was that it could not explain the spectra of atoms containing more than one electron. In order to increase the explanatory power of the model, Sommerfeld hypothesized the existence of elliptical orbits. This study has the following objectives: 1) Formulation of criteria based on a history and philosophy of science framework; and 2) Evaluation of university-level general chemistry textbooks based on the criteria, published in Italy and U.S.A. Presentation of a textbook was considered to be "satisfactory" if it included a description of the Bohr-Sommerfeld model along with diagrams of the elliptical orbits. Of the 28 textbooks published in Italy that were analyzed, only five were classified as "satisfactory". Of the 46 textbooks published in U.S.A., only three were classified as "satisfactory". This study has the following educational implications: a) Sommerfeld's innovation (auxiliary hypothesis) by introducing elliptical orbits, helped to restore the viability of Bohr's model; b) Bohr-Sommerfeld's model went no further than the alkali metals, which led scientists to look for other models; c) This clearly shows that scientific models are tentative in nature; d) Textbook authors and chemistry teachers do not consider the tentative nature of scientific knowledge to be important; e) Inclusion of the Bohr-Sommerfeld model in textbooks can help our students to understand how science progresses.

  16. Bad chemistry

    OpenAIRE

    Petsko, Gregory A

    2004-01-01

    General chemistry courses haven't changed significantly in forty years. Because most basic chemistry students are premedical students, medical schools have enormous influence and could help us start all over again to create undergraduate chemistry education that works.

  17. From Bhopal to Cold Fusion: A Case-Study Approach to Writing Assignments in Honors General Chemistry

    Science.gov (United States)

    Chamely-Wiik, Donna M.; Haky, Jerome E.; Galin, Jeffrey R.

    2012-01-01

    Faculty from the chemistry and English departments have developed a combined second-semester honors general chemistry and college writing course that fosters critical thinking through challenging writing assignments. Examples of case-study writing assignments and guidelines are provided that faculty at other institutions can adapt in similar…

  18. Introduction of Mass Spectrometry in an First-Semester General Chemistry Laboratory Course: Quantification of Mtbe or Dmso in Water

    Science.gov (United States)

    Solow, Mike

    2004-01-01

    Quantification of a contaminant in water provides the first-year general chemistry students with a tangible application of mass spectrometry. The relevance of chemistry to assessing and solving environmental problems is highlighted for students when they perform mass spectroscopy experiments.

  19. Using Graphs of Gibbs Energy versus Temperature in General Chemistry Discussions of Phase Changes and Colligative Properties

    Science.gov (United States)

    Hanson, Robert M.; Riley, Patrick; Schwinefus, Jeff; Fischer, Paul J.

    2008-01-01

    The use of qualitative graphs of Gibbs energy versus temperature is described in the context of chemical demonstrations involving phase changes and colligative properties at the general chemistry level. (Contains 5 figures and 1 note.)

  20. Modeling and analysis of aerosol processes in an interactive chemistry general circulation model

    Science.gov (United States)

    Verma, Sunita; Boucher, O.; Reddy, M. S.; Upadhyaya, H. C.; Le van, P.; Binkowski, F. S.; Sharma, O. P.

    2007-02-01

    An "online" aerosol dynamics and chemistry module is included in the Laboratoire de Météorologie Dynamique general circulation model (LMDZ), so that the chemical species are advected at each dynamical time step and evolve through chemical and physical processes that have been parameterized consistently with the meteorology. These processes include anthropogenic and biogenic emissions, over 50 gas/aqueous phase chemical reactions, transport due to advection, vertical diffusion and convection, dry deposition and wet scavenging. We have introduced a size-resolved representation of aerosols which undergo various processes such as coagulation, nucleation and dry and wet scavenging. The model considers 16 prognostic tracers: water vapor, liquid water, dimethyl sulfide (DMS), hydrogen sulfide (H2S), dimethyl sulphoxide (DMSO), methanesulphonic acid (MSA), sulfur dioxide (SO2), nitrogen oxides (NOX), carbon monoxide (CO), nitric acid (HNO3), ozone (O3), hydrogen peroxide (H2O2), sulfate mass and number for Aitken and accumulation modes. The scheme accounts for two-way interactions between tropospheric chemistry and aerosols. The oxidants and chemical species fields that represent the sulfate aerosol formation are evolved interactively with the model dynamics. A detailed description on the coupled climate-chemistry interactive module is presented with the evaluation of chemical species in winter and summer seasons. Aqueous phase reactions in cloud accounted for 71% of sulfate production rate, while only 45% of the sulfate burden in the troposphere is derived from in-cloud oxidation.

  1. General Chemistry and Cellular and Molecular Biology: An Experiment in Curricular Symbiosis

    Science.gov (United States)

    Truman Schwartz, A.; Serie, Jan

    2001-11-01

    During the 1998-99 academic year, with the support of the Howard Hughes Medical Institute, we co-taught integrated courses in general chemistry and cell biology to 23 first-year students. The double course was organized around six units: I. Energetics: Harvesting (Bio)Chemical Energy; II. The Regulation of Biological Processes: Chemical Kinetics and Equilibrium; III. Membranes and Electrochemical Gradients; IV. Acids and Bases and the Regulation of pH; V. Intracellular Compartments and Transport; and VI. Cellular Communication. The chemistry and biology were both taught in a manner meant to enhance understanding of these major themes and to emphasize the relationships between the two disciplines. Both of us were present for all class sessions and shared teaching responsibilities. The examinations, which corresponded to the units, also stressed the interdependence of biology and chemistry. The laboratory components were not integrated; rather the students were dispersed among laboratory sections shared with students from more traditional lecture sections. The paper reports on this experiment in curricular symbiosis, which proved to be a challenging and rewarding learning experience for both the students and us.

  2. Implementation of a PETN failure model using ARIA's general chemistry framework

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, Michael L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-01

    We previously developed a PETN thermal decomposition model that accurately predicts thermal ignition and detonator failure [1]. This model was originally developed for CALORE [2] and required several complex user subroutines. Recently, a simplified version of the PETN decomposition model was implemented into ARIA [3] using a general chemistry framework without need for user subroutines. Detonator failure was also predicted with this new model using ENCORE. The model was simplified by 1) basing the model on moles rather than mass, 2) simplifying the thermal conductivity model, and 3) implementing ARIA’s new phase change model. This memo briefly describes the model, implementation, and validation.

  3. What Do Conceptual Holes in Assessment Say about the Topics We Teach in General Chemistry?

    Science.gov (United States)

    Luxford, Cynthia J.; Holme, Thomas A.

    2015-01-01

    Introductory chemistry has long been considered a service course by various departments that entrust chemistry departments with teaching their students. As a result, most introductory courses include a majority of students who are not chemistry majors, and many are health and science related majors who are required to take chemistry. To identify…

  4. Ascorbic Acid as a Standard for Iodometric Titrations. An Analytical Experiment for General Chemistry

    Science.gov (United States)

    Silva, Cesar R.; Simoni, Jose A.; Collins, Carol H.; Volpe, Pedro L. O.

    1999-10-01

    Ascorbic acid is suggested as the weighable compound for the standardization of iodine solutions in an analytical experiment in general chemistry. The experiment involves an iodometric titration in which iodine reacts with ascorbic acid, oxidizing it to dehydroascorbic acid. The redox titration endpoint is determined by the first iodine excess that is complexed with starch, giving a deep blue-violet color. The results of the titration of iodine solution using ascorbic acid as a calibration standard were compared with the results acquired by the classic method using a standardized solution of sodium thiosulfate. The standardization of the iodine solution using ascorbic acid was accurate and precise, with the advantages of saving time and avoiding mistakes due to solution preparation. The colorless ascorbic acid solution gives a very clear and sharp titration end point with starch. It was shown by thermogravimetric analysis that ascorbic acid can be dried at 393 K for 2 h without decomposition. This experiment allows general chemistry students to perform an iodometric titration during a single laboratory period, determining with precision the content of vitamin C in pharmaceutical formulations.

  5. The effects of disequilibrium carbon chemistry in general circulation models of hot Jupiters

    Science.gov (United States)

    Steinrueck, Maria Elisabeth; Parmentier, Vivien; Showman, Adam P.

    2017-10-01

    Abundances of methane (CH4) and carbon monoxide (CO) are expected to be in disequilibrium in the photospheres of hot Jupiter exoplanets due to transport-induced quenching. It has been proposed that including this effect in general circulation models (GCMs) could resolve the mismatch between models and the observed 4.5 micron phase curves of hot Jupiters HD 189733b and HD 209458b.We modified the SPARC/MITgcm to mimic quenched carbon chemistry by assuming a constant ratio of CH4 to CO to calculate the opacities. Water abundances are modified accordingly so that the number of oxygen atoms is conserved. We ran global circulation models of HD 189733b assuming different values of the CH4/CO ratio. The change in temperature structure due to the quenched abundances is significant enough to affect the emission spectra. Thus, the radiative effect of the quenched abundances should be included in global circulation modelsWe show that including disequilibrium effects does not lower the 4.5 micron night side fluxes. If CO is the dominant species, as predicted by kinetics models, the increased CO opacity is offset by a lower water opacity. In this case, the 4.5 micron band turns out to be a bad diagnostic for disequilibrium carbon chemistry. As a consequence, disequilibrium carbon chemistry does not provide a good explanation for the small nightside flux observed at 4.5 microns in HD 189733b. The 3.6 Spitzer band should be a better indicator of disequilibrium chemistry. We find that the presence of quenched abundances always reduces the phase curve amplitude at 3.6 microns compared to the chemical equilibrium case, such that they are inconsistent with existing observations of HD 189733b. Therefore, other processes such as the presence of drag or night side clouds must be responsible for the shape of currently observed HD 189733b phase curves.We find that observations between 7 and 10 microns are a better diagnostic of disequilibrium carbon chemistry in the CO dominated regime

  6. Beyond "Inert" Ideas to Teaching General Chemistry from Rich Contexts: Visualizing the Chemistry of Climate Change (VC3)

    Science.gov (United States)

    Mahaffy, Peter G.; Holme, Thomas A.; Martin-Visscher, Leah; Martin, Brian E.; Versprille, Ashley; Kirchhoff, Mary; McKenzie, Lallie; Town, Marcy

    2017-01-01

    As one approach to moving beyond transmitting "inert" ideas to chemistry students, we use the term "teaching from rich contexts" to describe implementations of case studies or context-based learning based on systems thinking that provide deep and rich opportunities for learning crosscutting concepts through contexts. This…

  7. Investigations of Nitrogen Oxide Plasmas: Fundamental Chemistry and Surface Reactivity and Monitoring Student Perceptions in a General Chemistry Recitation

    Science.gov (United States)

    Blechle, Joshua M.

    2016-01-01

    Part I of this dissertation focuses on investigations of nitrogen oxide plasma systems. With increasing concerns over the environmental presence of NxOy species, there is growing interest in utilizing plasma-assisted conversion techniques. Advances, however, have been limited because of the lack of knowledge regarding the fundamental chemistry of…

  8. Climate Change Concepts and POGIL: Using climate change to teach general chemistry

    Science.gov (United States)

    King, D. B.; Lewis, J. E.; Anderson, K.; Latch, D.; Sutheimer, S.; Webster, G.; Middlecamp, C.; Moog, R.

    2013-12-01

    Climate change is a topic that can be used to engage students in a variety of courses and disciplines. Through an NSF-funded project, we have written a set of in-class POGIL (Process Oriented Guided Inquiry Learning) activities that use climate change topics to teach general chemistry concepts. POGIL is a pedagogical approach that uses group activities to teach content and process skills. In these group activities an initial model and a series of critical thinking questions are used to guide students through the introduction to or application of course content. Students complete the activities on their own, with the faculty member as a facilitator of learning, rather than a provider of information. Through assigned group roles and intentionally designed activity structure, process skills, such as teamwork, communication, and information processing, are developed during completion of the activity. While POGIL activities were initially developed for chemistry courses, this approach has now been used to create materials for use in other fields, such as biology, math, engineering and computer science. An additional component of this project is the incorporation of questions that relate to socio-scientific issues, e.g., the economic and social effects of climate change policies. The goal is for students to use evidence-based arguments in situations where opinion-based arguments are common. Key components (i.e., models and the corresponding critical thinking questions) of one activity will be presented. We will also report preliminary feedback based on initial classroom testing of several of the activities.

  9. Introductory Molecular Orbital Theory: An Honors General Chemistry Computational Lab as Implemented Using Three-Dimensional Modeling Software

    Science.gov (United States)

    Ruddick, Kristie R.; Parrill, Abby L.; Petersen, Richard L.

    2012-01-01

    In this study, a computational molecular orbital theory experiment was implemented in a first-semester honors general chemistry course. Students used the GAMESS (General Atomic and Molecular Electronic Structure System) quantum mechanical software (as implemented in ChemBio3D) to optimize the geometry for various small molecules. Extended Huckel…

  10. EVALUATION OF THE USE OF IPAD IN TEACHING GENERAL CHEMISTRY LAB TO FRESHMEN STUDENTS

    Directory of Open Access Journals (Sweden)

    N. EID

    2015-02-01

    Full Text Available It is generally accepted that the use of iPad enhances students’ engagement in the classroom. However, assessing the benefits of using iPad in teaching laboratory sessions have seen less attention, due to the hands-on nature of these courses. To do this assessment, iPad was applied in teaching two pilot sessions of the General Chemistry Lab, and students’ evaluation was compared to that of other students in sections taught by conventional teaching techniques. The evaluation was based on the students’ assessment of their achievements in meeting the main course outcomes, which indicated that the students in the classes taught using iPad showed more satisfaction with the course, and believed that they have better achieved the outcomes of the course compared to the conventional classes. Furthermore, the comparison process included the overall students’ quantitative performance, which showed insignificant difference between the two classes, with slightly better performance of students in normal classes in quizzes, whereas final exam marks were almost the same for both the iPad piloted students and conventional class students. The differences in quizzes results were attributed to the normal variation in the students’ academic merits. In addition, the piloted students were asked about their experience of using iPad in class and their satisfaction by using different iPad Apps. The feedback was collected and analysed, and the results showed that the students generally enjoyed using iPad in the class and appreciated all Apps.

  11. Last PS magnet refurbished

    CERN Document Server

    2009-01-01

    PS Magnet Refurbishment Programme Completed. The 51st and final refurbished magnet was transported to the PS on Tuesday 3 February. The repair and consolidation work on the PS started back in 2003 when two magnets and a busbar connection were found to be faulty during routine high-voltage tests. The cause of the fault was a combination of age and radiation on electrical insulation. After further investigation the decision was taken to overhaul half of the PS’s 100 magnets to reduce the risk of a similar fault. As from 20 February the PS ring will start a five-week test programme to be ready for operation at the end of March.

  12. Exploring students' interactions, arguments, and reflections in general chemistry laboratories with different levels of inquiry

    Science.gov (United States)

    Xu, Haozhi

    Students' learning in inquiry-based investigations has drawn considerable attention of the science education community. Inquiry activities can be viewed as knowledge construction processes in which students are expected to develop conceptual understanding and critical thinking abilities. Our study aimed to explore the effect of experiments with different levels of inquiry on students' interactions in the laboratory setting, as well as on students' written arguments and reflections. Our results are based on direct observations of group work in college general chemistry laboratories and analysis of associated written lab reports. The analysis of students' interactions in the laboratory was approached from three major analytic dimensions: Functional analysis, cognitive processing, and social processing. According to our results, higher levels of inquiry were associated with an increase in the relative frequency of episodes where students were engaged in proposing ideas versus asking and answering each others' questions. Higher levels of inquiry also favored episodes in which experimental work was approached in a more exploratory (versus procedural) manner. However, no major changes were observed in the extent to which students were engaged in either interpretive discussions of central scientific concepts and ideas. As part of our study we were also interested in characterizing the effects of experiments involving different levels of inquiry on the structure and adequacy of university general chemistry students' written arguments, as well as on the nature of their reflections about laboratory work. Our findings indicate that the level of inquiry of the observed experiments had no significant impact on the structure or adequacy of arguments generated by students. However, the level of inquiry of the experiments seemed to have a major impact on several areas of students' written reflections about laboratory work. In general, our results elicit trends and highlight issues

  13. Simulations of physics and chemistry of polar stratospheric clouds with a general circulation model

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, J.

    2005-04-20

    A polar stratospheric cloud submodel has been developed and incorporated in a general circulation model including atmospheric chemistry (ECHAM5/MESSy). The formation and sedimentation of polar stratospheric cloud (PSC) particles can thus be simulated as well as heterogeneous chemical reactions that take place on the PSC particles. For solid PSC particle sedimentation, the need for a tailor-made algorithm has been elucidated. A sedimentation scheme based on first order approximations of vertical mixing ratio profiles has been developed. It produces relatively little numerical diffusion and can deal well with divergent or convergent sedimentation velocity fields. For the determination of solid PSC particle sizes, an efficient algorithm has been adapted. It assumes a monodisperse radii distribution and thermodynamic equilibrium between the gas phase and the solid particle phase. This scheme, though relatively simple, is shown to produce particle number densities and radii within the observed range. The combined effects of the representations of sedimentation and solid PSC particles on vertical H{sub 2}O and HNO{sub 3} redistribution are investigated in a series of tests. The formation of solid PSC particles, especially of those consisting of nitric acid trihydrate, has been discussed extensively in recent years. Three particle formation schemes in accordance with the most widely used approaches have been identified and implemented. For the evaluation of PSC occurrence a new data set with unprecedented spatial and temporal coverage was available. A quantitative method for the comparison of simulation results and observations is developed and applied. It reveals that the relative PSC sighting frequency can be reproduced well with the PSC submodel whereas the detailed modelling of PSC events is beyond the scope of coarse global scale models. In addition to the development and evaluation of new PSC submodel components, parts of existing simulation programs have been

  14. Demonstration-Based Cooperative Testing in General Chemistry: A Broader Assessment-of-Learning Technique

    Science.gov (United States)

    Bowen, Craig W.; Phelps, Amy J.

    1997-06-01

    Demonstrations are often used as tools by instructors to help communicate ideas in chemistry. However, demonstrations can also be used as a means of measuring student learning. Understanding and problem solving in chemistry involves representing chemical phenomena at the symbolic, particulate and macroscopic levels. Measuring student learning of macroscopic understanding and its links to the other areas can be accomplished by using demonstrations as testing tools. The paper describes several examples of ways demonstrations are used to measure student learning in chemistry. Data collected as part of a study indicate that use of demonstration-based assessment activities throughout a term can lead to enhanced student conceptual understanding of chemistry.

  15. Implementation of Gas Chromatography and Microscale Distillation into the General Chemistry Laboratory Curriculum as Vehicles for Examining Intermolecular Forces

    Science.gov (United States)

    Csizmar, Clifford M.; Force, Dee Ann; Warner, Don L.

    2011-01-01

    As part of an NSF-funded Course Curriculum and Laboratory Improvement (CCLI) project that seeks, in part, to increase student exposure to scientific instrumentation, a gas chromatography experiment has been integrated into the second-semester general chemistry laboratory curriculum. The experiment uses affordable, commercially available equipment…

  16. Removal of Aromatic Pollutant Surrogate from Water by Recyclable Magnetite-Activated Carbon Nanocomposite: An Experiment for General Chemistry

    Science.gov (United States)

    Furlan, Ping Y.; Melcer, Michael E.

    2014-01-01

    A general chemistry laboratory experiment using readily available chemicals is described to introduce college students to an exciting class of nanocomposite materials. In a one-step room temperature synthetic process, magnetite nanoparticles are embedded onto activated carbon matrix. The resultant nanocomposite has been shown to combine the…

  17. Use of a PhET Interactive Simulation in General Chemistry Laboratory: Models of the Hydrogen Atom

    Science.gov (United States)

    Clark, Ted M.; Chamberlain, Julia M.

    2014-01-01

    An activity supporting the PhET interactive simulation, Models of the Hydrogen Atom, has been designed and used in the laboratory portion of a general chemistry course. This article describes the framework used to successfully accomplish implementation on a large scale. The activity guides students through a comparison and analysis of the six…

  18. Customized Videos on a YouTube Channel: A beyond the Classroom Teaching and Learning Platform for General Chemistry Courses

    Science.gov (United States)

    Ranga, Jayashree S.

    2017-01-01

    Videos are an integral part of online courses. In this study, customized YouTube videos were explored as teaching and learning materials in place of face-to-face discussion sessions in General Chemistry courses. The videos were created using a budget-friendly and interactive app on an iPad. The customized YouTube videos were available to students…

  19. Features of Representations in General Chemistry Textbooks: A Peek through the Lens of the Cognitive Load Theory

    Science.gov (United States)

    Nyachwaya, James M.; Gillaspie, Merry

    2016-01-01

    The goals of this study were (1) determine the prevalence of various features of representations in five general chemistry textbooks used in the United States, and (2) use cognitive load theory to draw implications of the various features of analyzed representations. We adapted the Graphical Analysis Protocol (GAP) (Slough et al., 2010) to look at…

  20. The Use of Molecular Modeling as "Pseudoexperimental" Data for Teaching VSEPR as a Hands-On General Chemistry Activity

    Science.gov (United States)

    Martin, Christopher B.; Vandehoef, Crissie; Cook, Allison

    2015-01-01

    A hands-on activity appropriate for first-semester general chemistry students is presented that combines traditional VSEPR methods of predicting molecular geometries with introductory use of molecular modeling. Students analyze a series of previously calculated output files consisting of several molecules each in various geometries. Each structure…

  1. Identification of Unknown Chloride Salts Using a Combination of Qualitative Analysis and Titration with Silver Nitrate: A General Chemistry Laboratory

    Science.gov (United States)

    Maines, Laina L.; Bruch, Martha D.

    2012-01-01

    General chemistry students often have difficulty writing balanced equations and performing stoichiometry calculations for precipitation reactions, in part because of difficulty understanding the symbolic notation used to represent chemical reactions. We have developed a problem-based experiment to improve student learning of these concepts, and…

  2. Quantitative Analysis in the General Chemistry Laboratory: Training Students to Analyze Individual Results in the Context of Collective Data

    Science.gov (United States)

    Ling, Chris D.; Bridgeman, Adam J.

    2011-01-01

    Titration experiments are ideal for generating large data sets for use in quantitative-analysis activities that are meaningful and transparent to general chemistry students. We report the successful implementation of a sophisticated quantitative exercise in which the students identify a series of unknown acids by determining their molar masses…

  3. The Influence of Self-Efficacy and Motivational Factors on Academic Performance in General Chemistry Course: A Modeling Study

    Science.gov (United States)

    Alci, Bulent

    2015-01-01

    This study aims to determine the predictive and explanatory model in terms of university students' academic performance in "General Chemistry" course and their motivational features. The participants were 169 university students in the 1st grade at university. Of the participants, 132 were female and 37 were male students. Regarding…

  4. Analytical capabilities and services of Lawrence Livermore Laboratory's General Chemistry Division. [Methods available at Lawrence Livermore

    Energy Technology Data Exchange (ETDEWEB)

    Gutmacher, R.; Crawford, R.

    1978-03-09

    This comprehensive guide to the analytical capabilities of Lawrence Livermore Laboratory's General Chemistry Division describes each analytical method in terms of its principle, field of application, and qualitative and quantitative uses. Also described are the state and quantity of sample required for analysis, processing time, available instrumentation, and responsible personnel.

  5. Two Methods of Determining Total Phenolic Content of Foods and Juices in a General, Organic, and Biological (GOB) Chemistry Lab

    Science.gov (United States)

    Shaver, Lee Alan; Leung, Sam H.; Puderbaugh, Amy; Angel, Stephen A.

    2011-01-01

    The determination of total phenolics in foods and fruit juices was used successfully as a laboratory experiment in our undergraduate general, organic, and biological (GOB) chemistry course. Two different colorimetric methods were used over three years and comparative student results indicate that a ferrous ammonium sulfate (FAS) indicator…

  6. Examining the Effectiveness of a Semi-Self-Paced Flipped Learning Format in a College General Chemistry Sequence

    Science.gov (United States)

    Hibbard, Lisa; Sung, Shannon; Wells, Breche´

    2016-01-01

    Flipped learning has come to the forefront in education. It maximizes learning by moving content delivery online, where learning can be self-paced, allowing for class time to focus on student-centered active learning. This five-year cross-sectional study assessed student performance in a college general chemistry for majors sequence taught by a…

  7. Impact of the Flipped Classroom on Student Performance and Retention: A Parallel Controlled Study in General Chemistry

    Science.gov (United States)

    Ryan, Michael D.; Reid, Scott A.

    2016-01-01

    Despite much recent interest in the flipped classroom, quantitative studies are slowly emerging, particularly in the sciences. We report a year-long parallel controlled study of the flipped classroom in a second-term general chemistry course. The flipped course was piloted in the off-semester course in Fall 2014, and the availability of the…

  8. Practical Work in Biology, Chemistry and Physics at Lower Secondary and General Upper Secondary Schools in Slovenia

    Science.gov (United States)

    Sorgo, Andrej; Spernjak, Andreja

    2012-01-01

    Syllabi in the science subjects, biology, chemistry and physics at lower and general upper secondary school are compared in the light of their underlying philosophies, goals, objectives and recognized importance in science teaching. Even though all syllabi were prepared within the same framework, great differences among syllabi concerning…

  9. Applications of mathematical learning models to student performance on general chemistry: Microcomputer drill and practice programs

    Science.gov (United States)

    Zitzewitz, Barbara S.; Berger, Carl F.

    Four drill and practice programs in general chemistry (Butler & Hough, 1982) were altered to keep records of response, scores, and response times as students used the programs. Mathematical learning models were applied to the resulting score and time data. When data for groups of students using the same programs were analyzed using the polynomial fit model of Kerlinger and Pedhazur (1973), significant results were found and in most cases the linear fit provided the only significant explanation for the variance in the data. The performance of individual students on selected programs was also analyzed using a linear model, a simple exponential saturation model, and a more complex model which incorporated ability and motivation factors into the exponential saturation model (Aldridge, 1983). Most of the students improved their performance linearly with time and none exhibited patterns characteristic of the Aldridge model. In some cases, the simple exponential saturation model provided an explanation of the data as probable as that of the linear model. The implications of the findings for science teaching are discussed.

  10. Inside the PS tunnel

    CERN Multimedia

    1974-01-01

    Pre-start work is going on at the end of the PS long shut-down. The photo shows secondary beams drawn from an internal target (bottom) towards South Hall, behind the shielding wall (top) (see also photo 7409012X).

  11. PS Control Room

    CERN Multimedia

    CERN PhotoLab

    1963-01-01

    The good old PS Control Room, all manual. For each parameter, a knob or a button to control it; for each, a light or meter or oscilloscope to monitor it; carefully written pages serve as the data bank; phones and intercom for communication. D.Dekkers is at the microphone, M.Valvini sits in front.

  12. PS auxiliary magnet

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    Units of the PS auxiliary magnet system. The picture shows how the new dipoles, used for vertical and horizontal high-energy beam manipulation, are split for installation and removal so that it is not necessary to break the accelerator vacuum. On the right, adjacent to the sector valve and the windings of the main magnet, is an octupole of the set.

  13. Introduction of Differential Scanning Calorimetry in a General Chemistry Laboratory Course: Determination of Heat Capacity of Metals and Demonstration of Law of Dulong and Petit

    Science.gov (United States)

    D'Amelia, Ronald P.; Stracuzzi, Vincent; Nirode, William F.

    2008-01-01

    Today's general chemistry students are introduced to many of the principles and concepts of thermodynamics. In first-year general chemistry undergraduate courses, thermodynamic properties such as heat capacity are frequently discussed. Classical calorimetric methods of analysis and thermal equilibrium experiments are used to determine heat…

  14. Take-Home Challenges: Extending Discovery-Based Activities beyond the General Chemistry Classroom

    Science.gov (United States)

    Mason, P. K.; Sarquis, A. M.

    1996-04-01

    In an effort to more effectively integrate the experimental nature of chemistry into our students' experiences, we are developing and implementing discovery-based activities into both the laboratory and lecture components of general chemistry. Below we describe and provide an example of a "take-home challenge" intended to supplement the lecture component of the course. These take-home challenges involve the student in chemistry exploration outside of class and extend the context of content and experimentation into a nontraditional laboratory environment. Over 25 take-home challenges have been developed to date. Preliminary evaluation of the impact of the take-home challenges shows that students reporting themselves as receiving a B or C grade in the course find the challenges very useful in helping them gain a conceptual understanding of the phenomena addressed. Students earning an A grade report little or no impact on their learning. Prepared as one-page handouts, each take-home challenge begins with a scene-setting introduction followed by pertinent background information, a list of materials to be collected, and any appropriate safety precautions. The exploration component of the activity integrates leading questions with the procedural instructions to help guide the students through the discovery process and challenge them to stretch their understanding of the chemistry. After completing a take-home challenge activity, students submit written reports containing responses to the questions posed, observations of data collected, and their responses to the challenge. The accompanying sample take-home challenge activity is provided as a novel adaptation of the belch phenomenon that challenges students to experiment in order to explain the factors that account for the observed behavior. Persons interested in field testing the take-home challenges with their classes should contact the authors. Belch Bottle Challenge: What factors are responsible for the behavior of a

  15. PS injection area

    CERN Multimedia

    1974-01-01

    Looking against the direction of protons in the main ring (left): the beam coming from the linac 1 either goes to the booster (on the right) or is deflected towards the PS to be directly injected into section 26 (facing the camera). Also shown the start of the TT2 line, ejected from straight section 16 to go towards the ISR passing over the beam line from the linac. (see Photo Archive 7409009)

  16. PS injection area

    CERN Multimedia

    1974-01-01

    To the right is the PS ring viewed along the direction of the protons. At the left the injection line coming from the 50 MeV Linac 1 (bottom) and going towards the 800 MeV booster, or deflected to the right to be injected directly into straight section 16. The drumlike element behind the (blue) dipole magnet is a 'debuncher' (a 200 MHz cavity). See photos 7409014X and 7409009.

  17. Utilization of the seven principles for good practice in undergraduate education in general chemistry by community college instructors

    Science.gov (United States)

    Panther Bishoff, Jennifer

    In recent years, higher education has undergone many changes. The advent of assessment, accountability, and a newfound focus on teaching have required faculty to examine how they are teaching. Administrators and faculty are beginning to recognize that learning is not a "one size fits all" enterprise. To this end, Chickering and Gamson developed an inventory that examined faculty utilization of the Seven Principles of Good Practice in Undergraduate Education. The seven principles included by the authors included faculty-student interaction, cooperative learning, active learning, giving prompt feedback, emphasizing time on task, communicating high expectations, and respecting diverse talents and ways of learning. It was determined by Chickering and Gamson, as well as many other researchers, that these seven principles were hallmarks of successful undergraduate education. Community colleges are important institutions to study, as many students begin their higher education at two-year colleges. Most students are also required to take one or more science classes for their general education requirements; therefore, many students must take at least one general chemistry course. Both community colleges and chemistry are rarely studied in literature, which makes this study important. Community college general chemistry instructors were surveyed using an online version of Chickering and Gamson's Faculty Inventory for the Seven Principles of Good Practice in Undergraduate Education. Responses were analyzed, and it was discovered that not only did instructors utilize the principles to a different extent, but there were also differences between genders as well as between the specific actions related to each principle.

  18. Getting Real: A General Chemistry Laboratory Program Focusing on "Real World" Substances

    Science.gov (United States)

    Kerber, Robert C.; Akhtar, Mohammad J.

    1996-11-01

    In order to confront the abstractness of the freshman chemistry syllabus and the consequent failure of students to relate what they learn to their everyday lives, we have designed a new freshman laboratory program. It is intended as an interface between the substances that surround the students in their ordinary lives and the abstract principles presented in chemistry classrooms (1). A laboratory should provide the organized experiences and observations that underlie the intellectual constructs of chemistry, and tying these experiences and observations to the real world can help to provide motivation for study of the principles. The freshman laboratory program constitutes the foundation for subsequent laboratory courses. However, the good habits we strive to develop there (careful observation, thorough record keeping, proper use of equipment, objective data analysis) are essential to all scientific work, and are intended to provide lasting educational value for all students, especially those who do not take later laboratory work. What We Do A list of the laboratory exercises carried out during 1994-1995 is presented in Table 1. The course incorporates the following features. 1. The exercises deal with recognizable, everyday substances, not just with "chemicals". That "baking soda" and "sodium bicarbonate" are the same is a chemical truism of which the students may be aware, but the visible presence of the Arm and Hammer box nevertheless helps them to make connections to the world outside the laboratory. Perceiving the connections, students may be inspired by curiosity to understand chemical phenomena better, not just to tolerate what they are being taught, as an irrelevant hurdle in the pursuit of a career. 2. Since many significant substances around students in the everyday world are organic, we work in the lab with organic as well as the usual inorganic materials. These include analgesics, vitamins, antifreeze, foodstuffs, dyestuffs, plastics, and fibers. In

  19. Productive whole-class discussions: A qualitative analysis of peer leader behaviors in general chemistry

    Science.gov (United States)

    Eckart, Teresa Mcclain

    The intention of this research was to describe behaviors and characteristics of General Chemistry I peer leaders using a pedagogical reform method referred to as Peer-led Guided Inquiry (PLGI), and to discuss the ways in which these peer leaders created productive whole-class discussions. This reform technique engaged students to work on guided inquiry activities while working cooperatively in small groups, led by undergraduate peer leaders. These sessions were video recorded and transcribed. The data was evaluated using grounded theory methods of analysis. This study examined the dialog between students and peer leaders, paying specific attention to question types and observed patterns of interactions. The research took shape by examining the kinds of questions asked by peer leaders and the purposes these questions served. In addition to looking at questions, different kinds of behaviors displayed by peer leaders during their small group sessions were also observed. A close examination of peer leader questions and behaviors aided in developing an answer to the overall research question regarding what factors are associated with productive whole-class discussions. Five major categories of peer leader behaviors evolved from the data and provided a means to compare and contrast productive whole-class discussions. While no category single-handedly determined if a discussion was good or bad, there was a tendency for peer leaders who exhibited positive traits in at least three of the following categories to have consistently better whole-class discussions: Procedural Practices, Supervisory Qualities, Questioning Techniques, Feedback/Responses, and Interpersonal Skills. Furthermore, each of the major categories is tied directly to Interpersonal, Communication, and Leadership skills and their interactions with each other. This study also addressed applications that each of these categories has on instructional practices and their need in peer leader training. In addition

  20. New reactions of germylenes with ketones and assessment of studio general chemistry

    Science.gov (United States)

    Sweeder, Ryan David

    New reaction modes of germylenes with ketones are presented. The germylene, Ge[CH(SiMe3)2]2 (1), will undergo reversible [4+2] addition with alkyl or aryl phenones to form a conjugated triene. Anthraquinone or 1,4-naphthylquinone will undergo a similar triene formation, but an insertion by a second molecule of 1 yields a product stable to reversion. In these cases, the second equivalent of germylene acts as a trap for the initially formed conjugated triene. A similar germylene, Ge[N(SiMe3)2]2 ( 2), reacts in analogous fashion with anthraquinone or 1,4-naphthylquinone indicating that it too engages in an equilibrium with phenones. The equilibrium for 2 with phenones lies heavily toward free 2 and phenone as no triene is detected via UV/Vis or NMR spectroscopies. Successful catalytic hydrogenation of the conjugate triene formed from the reaction of 1 with benzophenone is also presented. Other non-phenone ketones react with 1 via either CH or OH insertion. Three acetyl-containing ketones (acetone, butanone and cyclopropyl methyl ketone) have been observed to undergo CH insertion with 1 in the presence of one equivalent of MgCl2. The absence of MgCl 2 yields apparent OH insertion into the enol tautomer of the ketone. All secondary ketones examined undergo OH insertion even in the presence of MgCl2. The development, assessment and a description of a studio version of general chemistry are presented. This new course was implemented in the Fall 2002 semester at the University of Michigan. Content-based interviews focusing on equilibrium indicated that the students from the studio course had a better understanding of the underlying principles of equilibrium than their non-studio counterparts. The students enrolled in the studio course also gave more non-prompted explanations for a chemical reaction demonstrated during the interview, suggesting that they were more capable of transferring their chemical knowledge to new systems. The Motivated Strategies for Learning

  1. Analysis of Success in General Chemistry Based on Diagnostic Testing Using Logistic Regression

    Science.gov (United States)

    Legg, Margaret J.; Legg, Jason C.; Greenbowe, Thomas J.

    2001-08-01

    Several chemistry diagnostic and placement exams are used to help place chemistry students in an appropriate course or to determine strengths and weaknesses for specific topics in chemistry or math. The purpose of obtaining pre-course measurements is to increase students' academic success. Often these tests are used to predict the chance a student has in passing a course. This paper discusses the statistical methods of logistic regression applied to predicting the probability of passing a course, based on the scores on the California Chemistry Diagnostic Test at two different institutions with two different instructors over multiple years. This technique describes the relation of a test score (a continuous variable) to the probability of passing the class (a binary variable). Many papers in the Journal of Chemical Education have used a simple linear regression technique to correlate placement test scores with the proportion of students passing a course. The model assumptions are difficult to satisfy when using simple linear regression. Simple linear regression is useful when continuous predictor variables predict a continuous response, whereas logistic regression is useful when continuous predictor variables predict a binary response. Differences between simple linear regression and logistic regression and methods for evaluating linear regression model assumptions are discussed in detail. The fundamental concepts behind regression are described, with the caveats of using regression equations for predictions. By using logistic regression, instructors will be able to provide students with an estimate of their probability of passing the course.

  2. Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

    2008-01-01

    We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

  3. A General Chemistry Assignment Analyzing Environmental Contamination for the Depue, IL, National Superfund Site

    Science.gov (United States)

    Saslow Gomez, Sarah A.; Faurie-Wisniewski, Danielle; Parsa, Arlen; Spitz, Jeff; Spitz, Jennifer Amdur; Loeb, Nancy C.; Geiger, Franz M.

    2015-01-01

    The classroom exercise outlined here is a self-directed assignment that connects students to the environmental contamination problem surrounding the DePue Superfund site. By connecting chemistry knowledge gained in the classroom with a real-world problem, students are encouraged to personally connect with the problem while simultaneously…

  4. Green, Enzymatic Syntheses of Divanillin and Diapocynin for the Organic, Biochemistry, or Advanced General Chemistry Laboratory

    Science.gov (United States)

    Nishimura, Rachel T.; Giammanco, Chiara H.; Vosburg, David A.

    2010-01-01

    Environmentally benign chemistry is an increasingly important topic both in the classroom and the laboratory. In this experiment, students synthesize divanillin from vanillin or diapocynin from apocynin, using horseradish peroxidase and hydrogen peroxide in water. The dimerized products form rapidly at ambient temperature and are isolated by…

  5. Coordinated Implementation and Evaluation of Flipped Classes and Peer-Led Team Learning in General Chemistry

    Science.gov (United States)

    Robert, Jenay; Lewis, Scott E.; Oueini, Razanne; Mapugay, Andrea

    2016-01-01

    The research-based pedagogical strategy of flipped classes has been shown to be effective for increasing student achievement and retention in postsecondary chemistry classes. The purpose of flipped classes is to move content delivery (e.g., lecture) outside of the classroom, freeing more face-to-face time for active learning strategies. The…

  6. Pre-Assessment and Peer Tutoring as Measures to Improve Performance in Gateway General Chemistry Classes

    Science.gov (United States)

    Allenbaugh, R. J.; Herrera, K. M.

    2014-01-01

    Determining student readiness for gateway chemistry courses and providing underprepared students effective remediation are important as student bodies are growing increasingly diverse in their precollege preparation. The effectiveness of the ACT Mathematics Test and the Whimbey Analytical Skills Inventory (WASI) in predicting student success in…

  7. Investigating Macroscopic, Submicroscopic, and Symbolic Connections in a College-Level General Chemistry Laboratory

    Science.gov (United States)

    Thadison, Felicia Culver

    2011-01-01

    Explanations of chemical phenomena rely on understanding the behavior of submicroscopic particles. Because this level is "invisible," it is described using symbols such as models, diagrams and equations. For this reason, students often view chemistry as a "difficult" subject. The laboratory offers a unique opportunity for the students to…

  8. The testing effect in general chemistry: Effects of repeated testing on student performance across different test modes

    Science.gov (United States)

    Prisacari, Anna Agripina

    Research on the testing effect shows that practice tests are more effective than additional studying for enhancing learning. However, there has been little research directly addressing the role of additional testing when students take paper-based or computer-based tests in college courses. Accordingly, the purpose of this study was to investigate the role of the testing effect and test mode on student performance. The participants were 664 general chemistry students from two large universities in the Midwest and the Pacific Northwest. After covering the test material in their course, students completed two proctored practice tests that included 17 algorithmic question pairs, 5 conceptual pairs, and 2 definition pairs. Each practice test was delivered on computer or paper according to one of four conditions that were defined by the mode of the initial test and the mode of the final test. These conditions were: Computer-Computer, Computer-Paper, Paper-Computer, and Paper-Paper. After completing the initial practice test, students repeated half of the items. Feedback was provided after each test and performance was measured with normalized gains. After completing all of the tests, students were asked to indicate and explain their test mode preferences for general chemistry tests. Four major conclusions resulted from the study. First, the testing effect was found in all conditions, but varied in terms of the test mode. Paper-Computer showed the lowest gains and these gains were significantly lower than those for Paper-Paper. Gains from Computer-Paper and Paper-Paper were not significantly different from each other. Second, the test mode did not affect the students' performance on algorithmic questions, but affected their performance on conceptual and definition questions. Third, the gains from repeated items were significantly higher than the gains from non-repeated items. However, this testing effect was not consistent across all areas of chemistry content. Fourth, a

  9. At PS170 (APPLE)

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    APPLE stands for Antiproton-Proton to Pair of LEptons (an acronym of the ancestor experiment PAPLEP), the PS170 experiment setup at LEAR to study e+e-pair production in antiproton-proton annihilation by Padova-(CEN) Saclay- Torino Collaboration. It consisted of a liquid hydrogen target surrounded by several layers of proportional chambers in the vertical field of a C-magnet (this photo), a gas Cerenkov counter, wire chambers, hodoscopes, and an electromagnetic calorimeter (see photo 8302539X, 8302540X). See also photo 8301539X for the setup assembly at an early stage.

  10. Beyond iPS!

    Directory of Open Access Journals (Sweden)

    Editorial

    2012-01-01

    Full Text Available It’s undoubtedly a jubilant moment for scientists and clinicians working in the stem cell arena as Prof. Gurdon and Prof. Shinya Yamanaka have been chosen for the Nobel Prize in Physiology & Medicine this year. The mystery of cell biology is something unfathomable and probably the work of this duo as well as the other scientists, who have put their hands on in- vitro de-differentiation have opened our eyes to a new window or a new paradigm in cell biology. The iPS invention has brought a lot of hope in terms of potential direct benefits to treat several diseases, which have no definite options at the moment. But, we envisage that several spin-offs could come out of this invention and one very significant spin-off finding recently witnessed is the finding by Prof. Masaharu Seno and his team of researchers at the Okayama University, Japan (Chen L, et al. 2012, PLoS ONE 7(4:e33544.doi:10.1371/journal.pone.0033544. According to Prof. Seno, mouse iPS cells (miPS when cultured in the conditioned medium derived from cancer cell lines, differentiate into cancer stem cells (CSCs. While differentiating into CSCs, they do retain the potential to develop endothelial progenitor cells. Several questions arise here: 1.Are these miPS derived CSCs really pluripotent, even if the terminal differentiation destined to specific phenotypes? 2.Shouldn’t the Cancer Stem Cells be termed as cancer progenitor cells, as till date they are considered to be producing only cancer cells but not pluripotent to yield other types of normal tissues? The spin-offs could be infinite as the process of differentiation and de-differentiation happening due to trillions of signals and pathways, most still remaining not-so-well understood. A special mention should be made to Prof. Shinya Yamanaka as he has several sterling qualities to be a role-model for budding scientists. Apart from his passion for science, which made him shift his career from orthopedics to a cell biologist, his

  11. A study of two measures of spatial ability as predictors of success in different levels of general chemistry

    Science.gov (United States)

    Carter, Carolyn S.; Larussa, Mary A.; Bodner, George M.

    Preliminary data (Bodner and McMillen, 1986) suggested a correlation between spatial ability and performance in a general chemistry course for science and engineering majors. This correlation was seen not only on highly spatial tasks such as predicting the structures of ionic solids (r = 0.29), but also on tasks such as multiple-choice stoichiometry questions (r = 0.32) that might not be expected to involve spatial skills. To further investigate the relationship between spatial ability and performance in introductory chemistry courses, two spatial tests were given to 1648 students in a course for science and engineering majors (Carter, 1984) and 850 students in a course for students from nursing and agriculture (La-Russa, 1985) at Purdue. Scores on the spatial tests consistently contributed a small but significant amount to success on measures of performance in chemistry. Correlations were largest, however, for subscores that grouped questions that tested problem solving skills rather than rote memory or the application of simple algorithms, and correlations were also large for verbally complex questions thaty required the students to disembed and restructure relevant information.

  12. The Chemistry of a Mini

    Science.gov (United States)

    Jones, C. E.

    1972-01-01

    Describes various parts of a mini car and their chemical composition. Useful information is included for science teachers to relate basic chemistry concepts and techniques with their application in automobile industry. (PS)

  13. A Study of Concept Mapping as an Instructional Intervention in an Undergraduate General Chemistry Calorimetry Laboratory

    Science.gov (United States)

    Stroud, Mary W.

    This investigation, rooted in both chemistry and education, considers outcomes occurring in a small-scale study in which concept mapping was used as an instructional intervention in an undergraduate calorimetry laboratory. A quasi-experimental, multiple-methods approach was employed since the research questions posed in this study warranted the use of both qualitative and quantitative perspectives and evaluations. For the intervention group of students, a convenience sample, post-lab concept maps, written discussions, quiz responses and learning surveys were characterized and evaluated. Archived quiz responses for non-intervention students were also analyzed for comparison. Students uniquely constructed individual concept maps containing incorrect, conceptually correct and "scientifically thin" calorimetry characterizations. Students more greatly emphasized mathematical relationships and equations utilized during the calorimetry experiment; the meaning of calorimetry concepts was demonstrated to a lesser extent.

  14. Difficulties in generalizing modelling strategies in science: the case of physics and chemistry

    Directory of Open Access Journals (Sweden)

    Ileana M. Greca

    2005-03-01

    Full Text Available A review of the papers published in science education shows that the teaching centred in modelling is seemed as one of the most effective strategies for the improvement of the understanding of scientific concepts. However, a more carefully analyse also shows that what is being called as model or modelling process is very wide, and does not consider the differences in the specificities of the sciences. In this paper we try to discuss the differences and similitude in physics and chemistry modelling, having as reference the different explicative traditions in both sciences in the XVIII and XIX centuries. Finally, we discuss the didactic consequences of having in mind, or not, these differences.

  15. An analysis of cognitive growth of undergraduate students in a problem-centered general chemistry laboratory curriculum

    Science.gov (United States)

    Szeto, Alan Ka-Fai

    This study explored how undergraduate students in a new problem-centered General Chemistry Laboratory curriculum achieved cognitive growth. The new curriculum had three instructional segments: the highly-structured, semi-structured, and open-ended segments. The pedagogical approaches adopted were expository, guided-inquiry, and open-inquiry styles, respectively. Sixty-seven first-year undergraduate students who enrolled in the course in Spring semester, 2000, at Columbia University and three Ph.D.-level chemistry experts were included in the study. A qualitative approach was used including data collection through "think-aloud" problem solving; however, quantitative data such as test scores were also used. The findings from this study confirmed that chemistry experts possessed sophisticated and domain-specific conceptual knowledge structures; they mobilized and applied conceptual knowledge in conjunction with use of heuristics, tacit knowledge, and experience in authentic problem solving. They validated the new curriculum design in preparing students for inquiry-type of problem solving. For novices, solving of semi-structured before ill-structured problems had a positive effect on the solvers' chance of success in solving the latter type of problems as their abilities to mobilize and apply conceptual knowledge and use effective strategies appeared to be critical for successful problem solving. Students in the new course curriculum had grown cognitively as evidenced by their performance on the Case Study projects and Final Examination. High academic achievers were found to perform well independently while the medium and relatively low academic achievers should benefit from sustained and intensive instruction. It is proposed that ill-structured problems should be used to assess and identify the best from the better students. Finally, it was found that no significant change in students' attitudes had resulted from their curriculum experience. Gender and cognitive style

  16. Distinct iPS Cells Show Different Cardiac Differentiation Efficiency.

    Science.gov (United States)

    Ohno, Yohei; Yuasa, Shinsuke; Egashira, Toru; Seki, Tomohisa; Hashimoto, Hisayuki; Tohyama, Shugo; Saito, Yuki; Kunitomi, Akira; Shimoji, Kenichiro; Onizuka, Takeshi; Kageyama, Toshimi; Yae, Kojiro; Tanaka, Tomofumi; Kaneda, Ruri; Hattori, Fumiyuki; Murata, Mitsushige; Kimura, Kensuke; Fukuda, Keiichi

    2013-01-01

    Patient-specific induced pluripotent stem (iPS) cells can be generated by introducing transcription factors that are highly expressed in embryonic stem (ES) cells into somatic cells. This opens up new possibilities for cell transplantation-based regenerative medicine by overcoming the ethical issues and immunological problems associated with ES cells. Despite the development of various methods for the generation of iPS cells that have resulted in increased efficiency, safety, and general versatility, it remains unknown which types of iPS cells are suitable for clinical use. Therefore, the aims of the present study were to assess (1) the differentiation potential, time course, and efficiency of different types of iPS cell lines to differentiate into cardiomyocytes in vitro and (2) the properties of the iPS cell-derived cardiomyocytes. We found that high-quality iPS cells exhibited better cardiomyocyte differentiation in terms of the time course and efficiency of differentiation than low-quality iPS cells, which hardly ever differentiated into cardiomyocytes. Because of the different properties of the various iPS cell lines such as cardiac differentiation efficiency and potential safety hazards, newly established iPS cell lines must be characterized prior to their use in cardiac regenerative medicine.

  17. The role of self-regulated learning in explaining examination performance of college students in first-semester general chemistry

    Science.gov (United States)

    Beckley, Scott

    Many college students struggle with first-semester general chemistry. Prior studies have shown that a student's prior knowledge of chemistry, a cognitive factor, does not account for the total variance when measured by examination scores. This study explored the role of self-regulated learning (SRL) to identify the degree of success or failure of students with two outcome variables (i.e., American Chemical Society Comprehensive First-Term General Chemistry Examination (Form 2009) and hour-examination averages). The SRL construct consists of three interrelated components (i.e., cognitive, metacognitive, and motivational). SRL theory focuses on the idea of reciprocal determinism, in which the impact of one component of self-regulation affects the other two components. In the quantitative portion of this mixed methods study, eight measures of SRL were used to determine the `level' of self-regulation for each student. SRL variables were used in regression analysis and provided additional and unique variances. Cluster analysis techniques identified two distinct groups of students (i.e., adaptive and maladaptive). Generally, adaptive learners were associated with higher levels of SRL and success in the course; maladaptive learners had lower levels of SRL and struggled with the course demands. For the qualitative portion of the study, student volunteers (n = 8) were interviewed to gauge their views on the role of instruction in influencing their examination performances. The findings indicated that perceptions of teaching methods, demands of the course, course structure, feedback, and assessments were associated with the students' levels of self-regulation. Interviews revealed four SRL styles. Rote memorizers tended to fragment instruction and then memorize each fragment, while algorithmic memorizers tended to imitate the step-by-step problem-solving strategies of the instructor or the textbook. Globalizers were intrinsically motivated to learn the material but tended to

  18. SPS and PS Experiments Committee

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    OPEN SESSION: 09:00 Status report of NA58 / COMPASS: A. Magnon 09:40 Status report of PS212 / DIRAC: L. Tausher 10:10 PS212 / DIRAC Addendum: L. Nemenov CLOSED SESSION on Tuesday, 27 April 2004 after the open session, Main Building, 6th floor conference room

  19. Quantitative Clinical Chemistry Proteomics (qCCP) using mass spectrometry: general characteristics and application.

    Science.gov (United States)

    Lehmann, Sylvain; Hoofnagle, Andrew; Hochstrasser, Denis; Brede, Cato; Glueckmann, Matthias; Cocho, José A; Ceglarek, Uta; Lenz, Christof; Vialaret, Jérôme; Scherl, Alexander; Hirtz, Christophe

    2013-05-01

    Proteomics studies typically aim to exhaustively detect peptides/proteins in a given biological sample. Over the past decade, the number of publications using proteomics methodologies has exploded. This was made possible due to the availability of high-quality genomic data and many technological advances in the fields of microfluidics and mass spectrometry. Proteomics in biomedical research was initially used in 'functional' studies for the identification of proteins involved in pathophysiological processes, complexes and networks. Improved sensitivity of instrumentation facilitated the analysis of even more complex sample types, including human biological fluids. It is at that point the field of clinical proteomics was born, and its fundamental aim was the discovery and (ideally) validation of biomarkers for the diagnosis, prognosis, or therapeutic monitoring of disease. Eventually, it was recognized that the technologies used in clinical proteomics studies [particularly liquid chromatography-tandem mass spectrometry (LC-MS/MS)] could represent an alternative to classical immunochemical assays. Prior to deploying MS in the measurement of peptides/proteins in the clinical laboratory, it seems likely that traditional proteomics workflows and data management systems will need to adapt to the clinical environment and meet in vitro diagnostic (IVD) regulatory constraints. This defines a new field, as reviewed in this article, that we have termed quantitative Clinical Chemistry Proteomics (qCCP).

  20. Investigating the effectiveness of implementing the Science Writing Heuristic on student performance in general chemistry

    Science.gov (United States)

    Poock, Jason Ray

    This research investigated the effectiveness at how the Science Writing Heuristic in the freshman chemistry laboratory for science and engineering majors at Iowa State University during the fall and spring semesters of the 2002--2003 academic year, was implemented. The Science Writing Heuristic (SWH) consists of two components, writing to learn strategies and conducting the laboratory session in a student-centered, guided-inquiry fashion. The writing component replaced the standard laboratory report with a series of questions that guided the students' critical thinking along the lines of scientific investigation. The writing process helped students construct knowledge. Also critical to the successful implementation of the SWH was conducting the laboratory experiments in a student-centered, guided-inquiry fashion. Through the SWH the students became engaged in meaningful scientific dialogue that promoted knowledge construction. For the SWH to be properly implemented, a classroom dynamic between the teacher and the students should be established. The teacher provides the framework within which the laboratory experiment is conducted and the students respond to that guidance by becoming engaged in the learning process. Results of the study showed that student scores improved when the teacher properly implemented the SWH, when the students responded positively to the implementation of the SWH, and when there was a proper classroom dynamic created between the teacher and the students. This study revealed that successful implementation of the SWH was beneficial to females and low ability students. This research also demonstrated a connection between the implementation of a learning strategy in the laboratory component of a course and the subsequent benefit in student performance in the lecture component of the course.

  1. Choice of Study Resources in General Chemistry by Students Who Have Little Time to Study

    Science.gov (United States)

    Bunce, Diane M.; Komperda, Regis; Dillner, Debra K.; Lin, Shirley; Schroeder, Maria J.; Hartman, JudithAnn R.

    2017-01-01

    Students with an insufficient amount of time to study are becoming more prevalent in the general college population as many who enroll in college have competing responsibilities (full-time jobs, childcare, etc.). Such students are likely to choose study resources that they consider to be both effective and efficient. Students at the U.S. Naval…

  2. Textbook Treatments of Electrostatic Potential Maps in General and Organic Chemistry

    Science.gov (United States)

    Hinze, Scott R.; Williamson, Vickie M.; Deslongchamps, Ghislain; Shultz, Mary Jane; Williamson, Kenneth C.; Rapp, David N.

    2013-01-01

    Electrostatic potential maps (EPMs) allow for representation of key molecular-level information in a relatively simple and inexpensive format. As these visualizations become more prevalent in instruction, it is important to determine how students are exposed to them and supported in their use. A systematic review of current general and organic…

  3. HOW WE HAVE USED ITEM RESPONSE THEORY AND CLASSROOM MANAGEMENT TO IMPROVE STUDENT SUCCESS RATES IN LARGE GENERAL CHEMISTRY CLASSES

    Directory of Open Access Journals (Sweden)

    Brock L. Casselman

    Full Text Available Since 2012 we have tracked general chemistry student success rates at the University of Utah. In efforts to improve those rates we have implemented math prerequisites, changed our discussion session format, installed some metacognitive exercises aimed at the lowest quartile of students and instituted a flipped classroom model. Furthermore, using Item Response Theory we have identified what topics each individual student struggles with on practice tests. These steps have increased our success rates to ~76%. As well, student performance on nationally normed American Chemical Society final exams has improved to a median of 86 percentile. Our lowest quartile of students in spring 2016 scored at the 51 st percentile, above the national median.

  4. Population-based pediatric reference intervals for general clinical chemistry analytes on the Abbott Architect ci8200 instrument.

    Science.gov (United States)

    Ridefelt, Peter; Aldrimer, Mattias; Rödöö, Per-Olof; Niklasson, Frank; Jansson, Leif; Gustafsson, Jan; Hellberg, Dan

    2012-02-29

    Reference intervals are crucial decision-making tools aiding clinicians in differentiating between healthy and diseased populations. However, for children such values often are lacking or incomplete. Blood samples were obtained from 692 healthy children, aged 6 months to 18 years, recruited in daycare centers and schools. Twelve common general clinical chemistry analytes were measured on the Abbott Architect ci8200 platform; sodium, potassium, chloride, calcium, albumin-adjusted calcium, phosphate, magnesium, creatinine (Jaffe and enzymatic), cystatin C, urea and uric acid. Age- and gender specific pediatric reference intervals were defined by calculating the 2.5th and 97.5th percentiles. The data generated is primarily applicable to a Caucasian population when using the Abbott Architect platform, but could be used by any laboratory if validated for the local patient population.

  5. Picture this: The value of multiple visual representations for student learning of quantum concepts in general chemistry

    Science.gov (United States)

    Allen, Emily Christine

    Mental models for scientific learning are often defined as, "cognitive tools situated between experiments and theories" (Duschl & Grandy, 2012). In learning, these cognitive tools are used to not only take in new information, but to help problem solve in new contexts. Nancy Nersessian (2008) describes a mental model as being "[loosely] characterized as a representation of a system with interactive parts with representations of those interactions. Models can be qualitative, quantitative, and/or simulative (mental, physical, computational)" (p. 63). If conceptual parts used by the students in science education are inaccurate, then the resulting model will not be useful. Students in college general chemistry courses are presented with multiple abstract topics and often struggle to fit these parts into complete models. This is especially true for topics that are founded on quantum concepts, such as atomic structure and molecular bonding taught in college general chemistry. The objectives of this study were focused on how students use visual tools introduced during instruction to reason with atomic and molecular structure, what misconceptions may be associated with these visual tools, and how visual modeling skills may be taught to support students' use of visual tools for reasoning. The research questions for this study follow from Gilbert's (2008) theory that experts use multiple representations when reasoning and modeling a system, and Kozma and Russell's (2005) theory of representational competence levels. This study finds that as students developed greater command of their understanding of abstract quantum concepts, they spontaneously provided additional representations to describe their more sophisticated models of atomic and molecular structure during interviews. This suggests that when visual modeling with multiple representations is taught, along with the limitations of the representations, it can assist students in the development of models for reasoning about

  6. The atmospheric chemistry general circulation model ECHAM5/MESSy1: consistent simulation of ozone from the surface to the mesosphere

    Directory of Open Access Journals (Sweden)

    P. Jöckel

    2006-01-01

    Full Text Available The new Modular Earth Submodel System (MESSy describes atmospheric chemistry and meteorological processes in a modular framework, following strict coding standards. It has been coupled to the ECHAM5 general circulation model, which has been slightly modified for this purpose. A 90-layer model setup up to 0.01 hPa was used at spectral T42 resolution to simulate the lower and middle atmosphere. With the high vertical resolution the model simulates the Quasi-Biennial Oscillation. The model meteorology has been tested to check the influence of the changes to ECHAM5 and the radiation interactions with the new representation of atmospheric composition. In the simulations presented here a Newtonian relaxation technique was applied in the tropospheric part of the domain to weakly nudge the model towards the analysed meteorology during the period 1998–2005. This allows an efficient and direct evaluation with satellite and in-situ data. It is shown that the tropospheric wave forcing of the stratosphere in the model suffices to reproduce major stratospheric warming events leading e.g. to the vortex split over Antarctica in 2002. Characteristic features such as dehydration and denitrification caused by the sedimentation of polar stratospheric cloud particles and ozone depletion during winter and spring are simulated well, although ozone loss in the lower polar stratosphere is slightly underestimated. The model realistically simulates stratosphere-troposphere exchange processes as indicated by comparisons with satellite and in situ measurements. The evaluation of tropospheric chemistry presented here focuses on the distributions of ozone, hydroxyl radicals, carbon monoxide and reactive nitrogen compounds. In spite of minor shortcomings, mostly related to the relatively coarse T42 resolution and the neglect of inter-annual changes in biomass burning emissions, the main characteristics of the trace gas distributions are generally reproduced well. The MESSy

  7. Effectiveness of Podcasts Delivered on Mobile Devices as a Support for Student Learning During General Chemistry Laboratories

    Science.gov (United States)

    Powell, Cynthia B.; Mason, Diana S.

    2013-04-01

    Chemistry instructors in teaching laboratories provide expert modeling of techniques and cognitive processes and provide assistance to enrolled students that may be described as scaffolding interaction. Such student support is particularly essential in laboratories taught with an inquiry-based curriculum. In a teaching laboratory with a high instructor-to-student ratio, mobile devices can provide a platform for expert modeling and scaffolding during the laboratory sessions. This research study provides data collected on the effectiveness of podcasts delivered as needed in a first-semester general chemistry laboratory setting. Podcasts with audio and visual tracks covering essential laboratory techniques and central concepts that aid in experimental design or data processing were prepared and made available for students to access on an as-needed basis on iPhones® or iPod touches®. Research focused in three areas: the extent of podcast usage, the numbers and types of interactions between instructors and student laboratory teams, and student performance on graded assignments. Data analysis indicates that on average the podcast treatment laboratory teams accessed a podcast 2.86 times during the laboratory period during each week that podcasts were available. Comparison of interaction data for the lecture treatment laboratory teams and podcast treatment laboratory teams reveals that scaffolding interactions with instructors were statistically significantly fewer for teams that had podcast access rather than a pre-laboratory lecture. The implication of the results is that student laboratory teams were able to gather laboratory information more effectively when it was presented in an on-demand podcast format than in a pre-laboratory lecture format. Finally, statistical analysis of data on student performance on graded assignments indicates no significant differences between outcome measures for the treatment groups when compared as cohorts. The only statistically

  8. Generalized Graphs, Methods for Obtaining Graph Spectra. Application of Graph Spectra in Chemistry

    Science.gov (United States)

    Shen, Mingzuo

    Various graphical methods in the literature for getting at some features of the MO energy level spectra of especially pi systems and some related three-dimensional molecules are studied in detail. These include the graphical methods of Sinanoglu (although its mathematical, quantum-physical foundations, e.g. Sinanoglu's structural-covariance theory, are not discussed in this thesis), the edge-deletion method of Jiang, the specialized method of Sheng for benzenoid graphs, pairing theorems, graph splitting methods of e.g. McClelland, and more general one of R. A. Davidson. Of these the Sinanoglu method is found to be the only one generally applicable to diverse types of molecules without the need to introduce additional and complicated rules for each new graph type. The Sinanoglu method however is intended to be only a qualitative tool (giving the number of bonding, nonbonding, and antibonding levels and their changes upon reaction or geometrical distortions, large or small, of the molecule). Thus the other methods, although highly specialized, could be of help in getting some further information on the spectra. In particular, the "negative graph" concept in Chapter 3 of this thesis would be found useful in ascertaining the energy gap between the lowest and highest MO levels. In case where the Sinanoglu method cannot distinguish between differing stabilities of two molecules with the same signature and number of elections, this energy gap will be particularly useful. In the thesis, many alternative and simpler derivations of the graph-theoretic methods of Jiang, Davidson and others mentioned above are given. Some methods are generalized further. In the last chapter of the thesis starting with S 5.3, the graphical method is applied extensively to various types of molecules thought to have through-space interactions. Especially the Sinanoglu method is used to obtain the signature (instead of using a computer) and qualitative stabilities of these molecules are discussed

  9. Quantitative Determination of Iron in Limonite Using Spectroscopic Methods with Senior and General Chemistry Students: Geology-Inspired Chemistry Lab Explorations

    Science.gov (United States)

    Bopegedera, A. M. R. P.; Coughenour, Christopher L.; Oswalt, Andrew J.

    2016-01-01

    Limonite is the field term for a mixed assemblage of ferric oxyhydroxides, often containing nonferric silicate impurities. It is abundant on Earth's surface, possesses variable iron content, and is easily recognized by distinctive yellow and ochre hues. Limonite is a unique centerpiece for undergraduate chemistry laboratories because each sample…

  10. submitter Measurement of intrinsic rise times for various L(Y)SO and LuAG scintillators with a general study of prompt photons to achieve 10 ps in TOF-PET

    CERN Document Server

    Gundacker, Stefan; Pauwels, Kristof; Lecoq, Paul

    2016-01-01

    The coincidence time resolution (CTR) of scintillator based detectors commonly used in positron emission tomography is well known to be dependent on the scintillation decay time (${{\\tau}_{d}}$ ) and the number of photons detected (${{n}^{\\prime}}$ ), i.e. $CTR\\propto \\sqrt{{{\\tau}_{d}}/{{n}^{\\prime}}}$ . However, it is still an open question to what extent the scintillation rise time (${{\\tau}_{r}}$ ) and other fast or prompt photons, e.g. Cherenkov photons, at the beginning of the scintillation process influence the CTR. This paper presents measurements of the scintillation emission rate for different LSO type crystals, i.e. LSO:Ce, LYSO:Ce, LSO:Ce codoped Ca and LGSO:Ce. For the various LSO-type samples measured we find an average value of 70 ps for the scintillation rise time, although some crystals like LSO:Ce codoped Ca seem to have a much faster rise time in the order of 20 ps. Additional measurements for LuAG:Ce and LuAG:Pr show a rise time of 535 ps and 251 ps, respectively. For these crystals, promp...

  11. Effect of Peer-Led Team Learning (PLTL) on Student Achievement, Attitude, and Self-Concept in College General Chemistry in Randomized and Quasi Experimental Designs

    Science.gov (United States)

    Chan, Julia Y. K.; Bauer, Christopher F.

    2015-01-01

    This study investigated exam achievement and affective characteristics of students in general chemistry in a fully-randomized experimental design, contrasting Peer-Led Team Learning (PLTL) participation with a control group balanced for time-on-task and study activity. This study population included two independent first-semester courses with…

  12. "Greening" a Familiar General Chemistry Experiment: Coffee Cup Calorimetry to Determine the Enthalpy of Neutralization of an Acid-Base Reaction and the Specific Heat Capacity of Metals

    Science.gov (United States)

    Bopegedera, A. M. R. P.; Perera, K. Nishanthi R.

    2017-01-01

    Coffee cup calorimetry, performed with calorimeters made with styrofoam coffee cups, is a familiar experiment in the general chemistry laboratory. These calorimeters are inexpensive, easy to use, and provide good insulation for most thermodynamics experiments. This paper presents the successful substitution of paper coffee cups for styrofoam cups…

  13. A Reconstruction of Development of the Periodic Table Based on History and Philosophy of Science and Its Implications for General Chemistry Textbooks

    Science.gov (United States)

    Brito, Angmary; Rodriguez, Maria A.; Niaz, Mansoor

    2005-01-01

    The objectives of this study are: (a) elaboration of a history and philosophy of science (HPS) framework based on a reconstruction of the development of the periodic table; (b) formulation of seven criteria based on the framework; and (c) evaluation of 57 freshman college-level general chemistry textbooks with respect to the presentation of the…

  14. Simulating organic species with the global atmospheric chemistry general circulation model ECHAM5/MESSy1: a comparison of model results with observation

    NARCIS (Netherlands)

    Pozzer, A.; Jöckel, P.; Tost, H.; Sander, R.; Ganzeveld, L.N.; Kerkweg, A.; Lelieveld, J.

    2007-01-01

    The atmospheric-chemistry general circulation model ECHAM5/MESSy1 is evaluated with observations of different organic ozone precursors. This study continues a prior analysis which focused primarily on the representation of atmospheric dynamics and ozone. We use the results of the same reference

  15. Bringing out the "Main Characters" in General Chemistry: Can Creating a Sense of Narrative in the Classroom and for the Textbook Aid Long-Term Memory?

    Science.gov (United States)

    Chang, Junyoung; Churchill, David

    2011-01-01

    A new approach for teaching general chemistry is presented and discussed. Importantly, a storyline approach is provided in which the same chemical item or concept is reintroduced and embellished from chapter to chapter. The intention is to bring more connectivity between the various seemingly unrelated chapters. This might lead to a more…

  16. Yielding Unexpected Results: Precipitation of Ba[subscript3](PO[subscript4])[subscript2] and Implications for Teaching Solubility Principles in the General Chemistry Curriculum

    Science.gov (United States)

    Hazen, Jeffery L.; Cleary, David A.

    2014-01-01

    Precipitation of barium phosphate from aqueous solutions of a barium salt and a phosphate salt forms the basis for a number of conclusions drawn in general chemistry. For example, the formation of a solid white precipitate is offered as evidence that barium phosphate is insoluble. Furthermore, analysis of the supernatant is used to illustrate the…

  17. Structure and Evaluation of a Flipped General Chemistry Course as a Model for Small and Large Gateway Science Courses at an Urban Public Institution

    Science.gov (United States)

    Deri, Melissa A.; Mills, Pamela; McGregor, Donna

    2018-01-01

    A flipped classroom is one where students are first introduced to content outside of the classroom. This frees up class time for more active learning strategies and has been shown to enhance student learning in high school and college classrooms. However, many studies in General Chemistry, a college gateway science course, were conducted in small…

  18. Analyzing General Chemistry Texts' Treatment of Rates of Change Concepts in Reaction Kinetics Reveals Missing Conceptual Links

    Science.gov (United States)

    Seethaler, Sherry; Czworkowski, John; Wynn, Lynda

    2018-01-01

    Change over time is a crosscutting theme in the sciences that is pivotal to reaction kinetics, an anchoring concept in undergraduate chemistry, and students' struggles with rates of change are well-documented. Informed by the education scholarship in chemistry, physics, and mathematics, a research team with members from complementary disciplinary…

  19. Making Visible the Complexities of Problem Solving: An Ethnographic Study of a General Chemistry Course in a Studio Learning Environment

    Science.gov (United States)

    Kalainoff, Melinda Zapata

    Studio classrooms, designed such that laboratory and lecture functions can occur in the same physical space, have been recognized as a promising contributing factor in promoting collaborative learning in the sciences (NRC, 2011). Moreover, in designing for instruction, a critical goal, especially in the sciences and engineering, is to foster an environment where students have opportunities for learning problem solving practices (NRC, 2012a). However, few studies show how this type of innovative learning environment shapes opportunities for learning in the sciences, which is critical to informing future curricular and instructional designs for these environments. Even fewer studies show how studio environments shape opportunities to develop problem solving practices specifically. In order to make visible how the learning environment promotes problem solving practices, this study explores problem solving phenomena in the daily life of an undergraduate General Chemistry studio class using an ethnographic perspective. By exploring problem solving as a sociocultural process, this study shows how the instructor and students co-construct opportunities for learning in whole class and small group interactional spaces afforded in this studio environment and how the differential demands on students in doing problems requires re-conceptualizing what it means to "apply a concept".

  20. The PS locomotive runs again

    CERN Multimedia

    2001-01-01

    Over forty years ago, the PS train entered service to steer the magnets of the accelerator into place... ... a service that was resumed last Tuesday. Left to right: Raymond Brown (CERN), Claude Tholomier (D.B.S.), Marcel Genolin (CERN), Gérard Saumade (D.B.S.), Ingo Ruehl (CERN), Olivier Carlier (D.B.S.), Patrick Poisot (D.B.S.), Christian Recour (D.B.S.). It is more than ten years since people at CERN heard the rumbling of the old PS train's steel wheels. Last Tuesday, the locomotive came back into service to be tested. It is nothing like the monstrous steel engines still running on conventional railways -just a small electric battery-driven vehicle employed on installing the magnets for the PS accelerator more than 40 years ago. To do so, it used the tracks that run round the accelerator. In fact, it is the grandfather of the LEP monorail. After PS was commissioned in 1959, the little train was used more and more rarely. This is because magnets never break down, or hardly ever! In fact, the loc...

  1. The PS Booster hits 40

    CERN Multimedia

    Joannah Caborn Wengler

    2012-01-01

    Many accelerators’ "round" birthdays are being celebrated at CERN these days – the PS turned 50 in 2009, the SPS was 35 in 2011, and this year it's the turn of the PS Booster to mark its 40th anniversary. Originally designed to accelerate 1013 protons to 800 MeV, it has far exceeded its initial design performance over the years.   The PS Booster in the 1970s. Imagine the scene: a group of accelerator physicists staring expectantly at a monitor, when suddenly a shout of joy goes up as a signal flickers across the screen. Does that sound familiar? Well, turn the clock back 40 years (longer hair, wider trouser legs) and you have the situation at the PS Booster on 26 May 1972. On that day, beam was injected into the Booster for the first time. “It was a real buzz,” says Heribert Koziol, then Chairman of the Running-in Committee. “We were very happy – and also a little relieved – when the beam finally...

  2. New safety training for access to the PS complex areas

    CERN Multimedia

    2012-01-01

    Since 10/08/2012, a new course dedicated to the specific radiological risks in the accelerators of the PS complex has been available on SIR (https://sir.cern.ch/). This course complements the general classroom-based Radiation Safety training. Successful completion of the course will be obligatory and verified by the access system as from 01/11/2012 for access to the following accelerator areas: LINAC2, BOOSTER, PS and TT2. Information and reminder e-mails will be sent to all persons currently authorized to access the accelerators of the PS complex. For questions please contact the HSE unit and in particular, the Radiation Protection Group (+41227672504 or safety-rp-ps-complex@cern.ch).

  3. Measurement of intrinsic rise times for various L(Y)SO and LuAG scintillators with a general study of prompt photons to achieve 10 ps in TOF-PET.

    Science.gov (United States)

    Gundacker, Stefan; Auffray, Etiennette; Pauwels, Kristof; Lecoq, Paul

    2016-04-07

    The coincidence time resolution (CTR) of scintillator based detectors commonly used in positron emission tomography is well known to be dependent on the scintillation decay time (τd) and the number of photons detected (n'), i.e. CTR proportional variant √τd/n'. However, it is still an open question to what extent the scintillation rise time (τr) and other fast or prompt photons, e.g. Cherenkov photons, at the beginning of the scintillation process influence the CTR. This paper presents measurements of the scintillation emission rate for different LSO type crystals, i.e. LSO:Ce, LYSO:Ce, LSO:Ce codoped Ca and LGSO:Ce. For the various LSO-type samples measured we find an average value of 70 ps for the scintillation rise time, although some crystals like LSO:Ce codoped Ca seem to have a much faster rise time in the order of 20 ps. Additional measurements for LuAG:Ce and LuAG:Pr show a rise time of 535 ps and 251 ps, respectively. For these crystals, prompt photons (Cherenkov) can be observed at the beginning of the scintillation event. Furthermore a significantly lower rise time value is observed when codoping with calcium. To quantitatively investigate the influence of the rise time to the time resolution we measured the CTR with the same L(Y)SO samples and compared the values to Monte Carlo simulations. Using the measured relative light yields, rise- and decay times of the scintillators we are able to quantitatively understand the measured CTRs in our simulations. Although the rise time is important to fully explain the CTR variation for the different samples tested we determined its influence on the CTR to be in the order of a few percent only. This result is surprising because, if only photonstatistics of the scintillation process is considered, the CTR would be proportional to the square root of the rise time. The unexpected small rise time influence on the CTR can be explained by the convolution of the scintillation rate with the single photon time

  4. Preliminary Evaluation of PS300: A New Self-Lubricating High Temperature Composite Coating for Use to 800 C

    Science.gov (United States)

    Dellacorte, C.; Edmonds, B. J.

    1995-01-01

    This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800 C. PS300 is a metal bonded chrome oxide coating with silver and BaF2/CaF2 eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating, which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650 C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.

  5. The problem of polysemy in the first thousand words of the General Service List: A corpus study of secondary chemistry texts

    Science.gov (United States)

    Clemmons, Karina

    Vocabulary in a second language is an indispensable building block of all comprehension (Folse, 2006; Nation, 2006). Teachers in content area classes such as science, math, and social studies frequently teach content specific vocabulary, but are not aware of the obstacles that can occur when students do not know the basic words. Word lists such as the General Service List (GSL) were created to assist students and teachers (West, 1953). The GSL does not adequately take into account the high level of polysemy of many common English words, nor has it been updated by genre to reflect specific content domains encountered by secondary science students in today's high stakes classes such as chemistry. This study examines how many words of the first 1000 words of the GSL occurred in the secondary chemistry textbooks sampled, how often the first 1000 words of the GSL were polysemous, and specifically which multiple meanings occurred. A discussion of results includes word tables that list multiple meanings present, example phrases that illustrate the context surrounding the target words, suggestions for a GSL that is genre specific to secondary chemistry textbooks and that is ranked by meaning as well as type, and implications for both vocabulary materials and classroom instruction for ELLs in secondary chemistry classes. Findings are essential to second language (L2) researchers, materials developers, publishers, and teachers.

  6. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Srimath

    RESONANCE ⎜ March 2009. GENERAL ⎜ ARTICLE. Keywords. Green fluorescent protein,. FRET. Chemistry is Evergreen. 2008 Nobel Prize in Chemistry. Swagata Dasgupta. Swagata Dasgupta is an. Associate Professor in the. Department of Chemistry at IIT Kharagpur. Her research interests revolve around proteins and ...

  7. Comparison of High School Dual-Enrollment and Traditional First-Term General/Organic/Biochemistry College Chemistry Class Outcomes

    Science.gov (United States)

    Zuidema, Daniel R.; Eames, Kevin J.

    2014-01-01

    Student performance in a high school dual-enrollment chemistry course was compared with student performance in the corresponding traditional college course. The two courses were taught by the same instructor and evaluated using the same American Chemical Society (ACS) standardized examination. Interestingly, the high school dual-enrollment…

  8. The Application and Evaluation of a Two-Concept Diagnostic Instrument with Students Entering College General Chemistry

    Science.gov (United States)

    Heredia, Keily; Xu, Xiaoying; Lewis, Jennifer E.

    2012-01-01

    The Particulate Nature of Matter and Chemical Bonding Diagnostic Instrument (Othman J., Treagust D. F. and Chandrasegaran A. L., (2008), "Int. J. Sci. Educ.," 30(11), 1531-1550) is used to investigate college students' understanding of two chemistry concepts: particulate nature of matter and chemical bonding. The instrument, originally…

  9. Teaching Thermodynamics and Kinetics to Advanced General Chemistry Students and to Upper-Level Undergraduate Students Using PV Diagrams

    Science.gov (United States)

    Iyengar, Srinivasan S.; deSouza, Romualdo T.

    2014-01-01

    We describe how complex concepts in macroscopic chemistry, namely, thermodynamics and kinetics, can be taught at considerable depth both at the first-year undergraduate as well as upper levels. We begin with a careful treatment of PV diagrams, and by pictorially integrating the appropriate area in a PV diagram, we introduce work. This starting…

  10. The A[subscript 1c] Blood Test: An Illustration of Principles from General and Organic Chemistry

    Science.gov (United States)

    Kerber, Robert C.

    2007-01-01

    The glycated hemoglobin blood test, usually designated as the A[subscript 1c] test, is a key measure of the effectiveness of glucose control in diabetics. The chemistry of glucose in the bloodstream, which underlies the test and its impact, provides an illustration of the importance of chemical equilibrium and kinetics to a major health problem.…

  11. Interactive chemistry in the Laboratoire de Météorologie Dynamique general circulation model: model description and impact analysis of biogenic hydrocarbons on tropospheric chemistry

    Directory of Open Access Journals (Sweden)

    G. A. Folberth

    2006-01-01

    Full Text Available We present a description and evaluation of LMDz-INCA, a global three-dimensional chemistry-climate model, pertaining to its recently developed NMHC version. In this substantially extended version of the model a comprehensive representation of the photochemistry of non-methane hydrocarbons (NMHC and volatile organic compounds (VOC from biogenic, anthropogenic, and biomass-burning sources has been included. The tropospheric annual mean methane (9.2 years and methylchloroform (5.5 years chemical lifetimes are well within the range of previous modelling studies and are in excellent agreement with estimates established by means of global observations. The model provides a reasonable simulation of the horizontal and vertical distribution and seasonal cycle of CO and key non-methane VOC, such as acetone, methanol, and formaldehyde as compared to observational data from several ground stations and aircraft campaigns. LMDz-INCA in the NMHC version reproduces tropospheric ozone concentrations fairly well throughout most of the troposphere. The model is applied in several sensitivity studies of the biosphere-atmosphere photochemical feedback. The impact of surface emissions of isoprene, acetone, and methanol is studied. These experiments show a substantial impact of isoprene on tropospheric ozone and carbon monoxide concentrations revealing an increase in surface O3 and CO levels of up to 30 ppbv and 60 ppbv, respectively. Isoprene also appears to significantly impact the global OH distribution resulting in a decrease of the global mean tropospheric OH concentration by approximately 0.7×105 molecules cm-3 or roughly 8% and an increase in the global mean tropospheric methane lifetime by approximately seven months. A global mean ozone net radiative forcing due to the isoprene induced increase in the tropospheric ozone burden of 0.09 W m-2 is found. The key role of isoprene photooxidation in the global tropospheric redistribution of NOx is demonstrated. LMDz

  12. EDH 'Millionaire' in PS Division

    CERN Document Server

    2001-01-01

    Christmas cheer! Left to right: Gerard Lobeau receives a bottle of Champagne from Derek Mathieson and Jurgen De Jonghe in recognition of EDH's millionth document. At 14:33 on Monday 3 December a technician in PS division, Gerard Lobeau, unwittingly became part of an important event in the life of CERN's Electronic Document Handling system (EDH). While ordering some pieces of aluminum for one of the PS's 10Mhz RF cavities, he created EDH document number 1,000,000. To celebrate the event Derek Mathieson (EDH Project Leader) and Jurgen De Jonghe (Original EDH Project Leader) presented Mr Lobeau with a bottle of champagne. As with 93% of material requests, Mr Lobeau's order was delivered within 24 hours. 'I usually never win anything' said Mr Lobeau as he accepted his prize, 'I initially though there may have been a problem with EDH when the document number had so many zeros in it, and was then surprised to get a phone call from you a few minutes later.' The EDH team had been monitoring the EDH document number ...

  13. Annual Report 1984. Chemistry Department

    DEFF Research Database (Denmark)

    Funck, Jytte; Nielsen, Ole John

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, an......, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general.......This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry...

  14. Pressure Monitoring Using Hybrid fs/ps Rotational CARS

    Science.gov (United States)

    Kearney, Sean P.; Danehy, Paul M.

    2015-01-01

    We investigate the feasibility of gas-phase pressure measurements at kHz-rates using fs/ps rotational CARS. Femtosecond pump and Stokes pulses impulsively prepare a rotational Raman coherence, which is then probed by a high-energy 6-ps pulse introduced at a time delay from the Raman preparation. Rotational CARS spectra were recorded in N2 contained in a room-temperature gas cell for pressures from 0.1 to 3 atm and probe delays ranging from 10-330 ps. Using published self-broadened collisional linewidth data for N2, both the spectrally integrated coherence decay rate and the spectrally resolved decay were investigated as means for detecting pressure. Shot-averaged and single-laser-shot spectra were interrogated for pressure and the accuracy and precision as a function of probe delay and cell pressure are discussed. Single-shot measurement accuracies were within 0.1 to 6.5% when compared to a transducer values, while the precision was generally between 1% and 6% of measured pressure for probe delays of 200 ps or more, and better than 2% as the delay approached 300 ps. A byproduct of the pressure measurement is an independent but simultaneous measurement of the gas temperature.

  15. Assessing the Impact of New Research-Inspired General Chemistry Laboratory Experiments Using the Awareness of and Attitudes toward Scientific Research Inventory

    Science.gov (United States)

    Anzovino, Mary Elizabeth

    This work has three main components: 1.) The development of new research-inspired general chemistry laboratory experiments, 2.) The development of a new survey instrument to assess students' awareness of and attitudes toward scientific research, 3.) The utilization of that survey to assess the impacts of the new experiments. The value of undergraduate research experiences, both within and outside a course context, has been demonstrated in the literature. However, it is simply not feasible for all undergraduate students to participate in extracurricular research. Additionally, in many cases, integration of research modules into an undergraduate course is not realistic either. It is therefore necessary to assess the impacts of less complete, but still potentially significant, integration of research into the undergraduate curriculum via content drawn from current research at the University of Wisconsin--Madison. Two such experiments have been developed, in the areas of surfactants (synthesis and analysis) and reaction kinetics. Although a vast array of survey instruments exist to assess student attitudes toward science in general and specific fields such as chemistry, none of these instruments address scientific research. The Awareness of and Attitudes toward Scientific Research Inventory (AASRI) has been designed to fill this gap in the literature. The AASRI data exhibited evidence of good validity and reliability, suggesting that it is a useful assessment. A quasi-experimental study was conducted to evaluate the impact of the new research-inspired experiments in the general chemistry curriculum. The AASRI was used as a pre- and post-test for students who did and did not complete the new experiments. Although no significant differences were found between the groups, the data collected in the pre-test and post-test of both classes demonstrated evidence of good validity and reliability, and it is possible that a simple increase in the number of interventions would

  16. Coordination Chemistry of Life Processes: Bioinorganic Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Coordination Chemistry of Life Processes: Bioinorganic Chemistry. R N Mukherjee. General Article Volume 4 Issue 9 September 1999 pp 53-62. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. New Concepts of Quality Assurance in Analytical Chemistry: Will They Influence the Way We Conduct Science in General?

    DEFF Research Database (Denmark)

    Andersen, Jens; Glasdam, Sidsel-Marie; Larsen, Daniel Bo

    2016-01-01

    According to the guide Vocabulary in Metrology (VIM3) (JCGM, 2008), the definition of the concepts of trueness and accuracy has been revised, which has an important impact on analytical chemistry. Additionally, Eurachem/CITAC has published a new edition of the guide to Quantifying Uncertainty...... plasma optical emission spectrometry (ICP-OES) for determination of sodium, were evaluated in terms of the true level of uncertainty and revealed a genuine problem for science that was not addressed in VIM3 and QUAM. Comparison of theory and experimentation definitely requires statistical tools...

  18. 7 CFR 1753.37 - Plans and specifications (P&S).

    Science.gov (United States)

    2010-01-01

    ....37 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to... central office equipment. (2) The P&S shall specify the delivery and completion time required for each...

  19. Morphology and properties of SEBS block copolymer compatibilized PS/HDPE blends

    Czech Academy of Sciences Publication Activity Database

    Rek, V.; Vranješ, N.; Šlouf, Miroslav; Fortelný, Ivan; Jelčic, Ž.

    2008-01-01

    Roč. 40, č. 3 (2008), s. 237-251 ISSN 0095-2443 Grant - others:Ministry of Science, Education and Sport(HR) 0125059 Institutional research plan: CEZ:AV0Z40500505 Keywords : aPS/HDPE/SEBS blends * morphology * processing * rheological Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.658, year: 2008

  20. Global trend analysis of surface CO simulated using the global atmospheric chemistry general circulation model, EMAC (ECHAM5/MESSy)

    Science.gov (United States)

    Yoon, Jongmin; Pozzer, Andrea; Lelieveld, Jos

    2013-04-01

    Carbon monoxide (CO) is an important trace gas in tropospheric chemistry. It directly influences the concentration of tropospheric hydroxyl radical (OH), and therefore regulates the lifetimes of various tropospheric trace gases. Since anthropogenic activity produces about 60% of the annual global emission of the tropospheric CO, temporal trend analysis of surface CO is needed to understand the increasing (decreasing) influence of humans on the cleansing capacity of the atmosphere. In this study, the global trend of surface CO from 2001 to 2010 was estimated using the EMAC (ECHAM5/MESSy for Atmospheric Chemistry) model. The simulation is based on the emission scenario based on RCP8.5 (Representative Concentration Pathways). The global EMAC simulations of monthly surface CO are evaluated with monthly MOPITT (Measurements Of Pollution In The Troposphere) observations (i.e. MOP03TM), and the spatial correlations range from 0.87 to 0.97. The simulated trends are compared with the data from a global surface CO monitoring network, the World Data Centre for Greenhouse Gases (WDCGG), which includes also the NOAA/CMDL (Climate Monitoring and Diagnostic Laboratory of the National Oceanic and Atmospheric Administration) Cooperative Air Sampling Network. Over the United States and Western Europe, the significant decreases of surface CO are estimated at -49.7±2.7 and -38.6±2.7 ppbv per decade. In contrast, the surface CO increased by +12.4±10.2 and +7.2±3.7 ppbv per decade over South America and South Africa, respectively.

  1. Ps-atom scattering at low energies

    CERN Document Server

    Fabrikant, I I

    2015-01-01

    A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $v<1$ a.u. Our results show that the effect of the Ps-atom van der Waals interaction is weak compared to the polarization interaction in electron-atom and positron-atom scattering. As a result, the Ps scattering length for both Ar and Kr is positive, and the Ramsauer-Townsend minimum is not observed for Ps scattering from these targets. This makes Ps scattering quite different from electron scattering in the low-energy region, in contrast to the inter...

  2. Enhanced personal protection at the PS

    CERN Multimedia

    Samuel Morier Genoud

    2013-01-01

    Pictures 03, 06, 07 08 : Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system.Pictures 10, 12 ,13 : View of Building 271, the future control centre of the new PS complex safety system.

  3. PS, SL and LHC Auditoria change names

    CERN Document Server

    2003-01-01

    Following the replacement of the PS, SL and LHC Divisions by the AB and AT Divisions, the Auditoria are also changing their names. PS Auditorium is renamed AB Meyrin SL Auditorium is renamed AB Prévessin LHC Auditorium is renamed AT

  4. Polymer Chemistry in High School.

    Science.gov (United States)

    Stucki, Roger

    1984-01-01

    Discusses why polymer chemistry should be added to the general chemistry curriculum and what topics are appropriate (listing traditional with related polymer topics). Also discusses when and how these topics should be taught. (JN)

  5. Moving beyond feasibility in ultrafast shock chemistry experiments

    Science.gov (United States)

    Armstrong, Michael; Lewicki, James; Crowhurst, Jonathan; Zaug, Joseph; Radousky, Harry; Stavrou, Elissaios; Sawvel, April

    Although ultrafast hydrodynamic methods to investigate the chemistry of shocked materials on ps to ns time scales are generally mature, questions about the interpretation of such experiments remain. Most ultrafast experiments employ shock etalon methods whose interpretation depends on assumptions about the index of refraction of the shocked state. Further, although signatures for chemistry in longer time scale time-of-flight (ToF) experiments are well understood, ultrafast chemistry experiments have not typically employed ToF methods. The use of ToF methods in ultrafast experiments would enable a more straightforward connection to longer time scale data, and would generally provide more information than shock etalon methods. Finally, ultrafast experiments have not been performed over time scales greater than a few hundred of picoseconds, significantly limiting the scope of experiments to observe shocked chemistry under typical conditions at larger length scales. Here we address all of these issues by presenting data from shocked polymers obtained using both ToF and shock etalon methods, using a 1 ns pump and observation window. We compare the results of these two methods to reconcile data from these different methods and strengthen the interpretation of both types of experiment. Prepared by LLNL under Contract DE-AC52-07NA27344.

  6. On the crystallization behavior of syndiotactic-b-atactic polystyrene stereodiblock copolymers, atactic/syndiotactic polystyrene blends, and aPS/sPS blends modified with sPS-b-aPS

    Energy Technology Data Exchange (ETDEWEB)

    Annunziata, Liana, E-mail: liana.annunziatta@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France); Monasse, Bernard, E-mail: bernard.monasse@mines-paristech.fr [Mines-ParisTech, CEMEF, Centre de Mise en Forme des Matériaux, UMR CNRS 7635, Sophia Antipolis (France); Rizzo, Paola; Guerra, Gaetano [Dipartimento di Chimica e Biologia, Università degli studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano, SA (Italy); Duc, Michel [Total Petrochemicals Research Feluy, Zone Industrielle Feluy C, B-7181 Seneffe (Belgium); Carpentier, Jean-François, E-mail: jean-francois.carpentier@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France)

    2013-09-16

    Crystallization and morphological features of syndiotactic-b-atactic polystyrene stereodiblock copolymers (sPS-b-aPS), atactic/syndiotactic polystyrene blends (aPS/sPS), and aPS/sPS blends modified with sPS-b-aPS, with different compositions in aPS and sPS, have been investigated using differential scanning calorimetry (DSC), polarized light optical microscopy (POM) and wide angle X-ray diffraction (WAXRD) techniques. For comparative purposes, the properties of parent pristine sPS samples were also studied. WAXRD analyses revealed for all the samples, independently from their composition (aPS/sPS ratio) and structure (blends, block copolymers, blends modified with block copolymers), the same polymorphic β form of sPS. The molecular weight of aPS and sPS showed opposite effects on the crystallization of 50:50 aPS/sPS blends: the lower the molecular weight of aPS, the slower the crystallization while the lower the molecular weight of sPS, the faster the crystallization. DSC studies performed under both isothermal and non-isothermal conditions, independently confirmed by POM studies, led to a clear trend for the crystallization rate at a given sPS/aPS ratio (ca. 50:50 and 20:80): sPS homopolymers > sPS-b-aPS block copolymers ∼sPS/aPS blends modified with sPS-b-aPS copolymers > sPS/aPS blends. Interestingly, sPS-b-aPS block copolymers not only crystallized faster than blends, but also affected positively the crystallization behavior of blends. At 50:50 sPS/aPS ratio, blends (Blend-2), block copolymers (Cop-1) and blends modified with block copolymers (Blend-2-mod) crystallized via spherulitic crystalline growth controlled by an interfacial process. In all cases, an instantaneous nucleation was observed. The density of nuclei in block copolymers (160,000−190,000 nuclei mm{sup −3}) was always higher than that in blends and modified blends (30,000−60,000 nuclei mm{sup −3}), even for quite different sPS/aPS ratio. At 20:80 sPS/aPS ratio, the block copolymers

  7. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  8. The Breath of Chemistry

    DEFF Research Database (Denmark)

    Josephsen, Jens

    The present preliminary text is a short thematic presentation in biological inorganic chemistry meant to illustrate general and inorganic (especially coordination) chemistry in biochemistry. The emphasis is on molecular models to explain features of the complicated mechanisms essential to breathing...

  9. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 3. Chemistry is Everygreen - 2008 Nobel Prize in Chemistry. Swagata Dasgupta. General Article Volume 14 Issue 3 March 2009 pp 248-258. Fulltext. Click here to view fulltext PDF. Permanent link:

  10. Ps 22 in Gospels’ interpretation of Passion

    Directory of Open Access Journals (Sweden)

    Sylwester Jędrzejewski

    2012-09-01

    Full Text Available Ps 22 is a piece of artistically high poetry, clear images and metaphors, historical and prophetic references. The conviction of biblical scholars that the New Testament writers has recognized in Ps 22 prophetic witness of passion, accompanies the Church from its beginnings. The words of Jesus on the cross, taken from Ps 22: 2, have a character of lamentable re-symbolization of the prayer of Israel. These words establish a theological answer in the form of suitable credo as well. Dramatic question “why?” is connected with a proclamation and identification “My God”. The personal experience of oppression and death is included by Jesus in the history of his nation and in the experience of God. Ps 22 in the Gospels’ passion context becomes a proclamation form of prayer and a very personal, expressed in such dramatic circumstances confession of the faith.

  11. Yasp for LEIR to PS injection

    CERN Document Server

    Kain, V; Bartosik, H; Huschauer, A; Jacquet, D; Nicosia, D; Pasinelli, S; Wenninger, J

    2017-01-01

    The steering program YASP was introduced in the LEIRinjection as well as the extraction lines in 2016 to correctthe trajectories with well-known model based correctionalgorithms such as MICADO or SVD. In addition a YASPconfiguration was prepared to correct the extraction linetogether with the first turn of the PS. In this way the injectionoscillations can be corrected while keeping the trajectoryreasonable in the PS injection line.

  12. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Here we see the PS magnet string awaiting the replacement no. 6 magnet.

  13. General

    Indian Academy of Sciences (India)

    Page S20: NMR compound 4i. Page S22: NMR compound 4j. General: Chemicals were purchased from Fluka, Merck and Aldrich Chemical Companies. All the products were characterized by comparison of their IR, 1H NMR and 13C NMR spectroscopic data and their melting points with reported values. General procedure ...

  14. Validity and reliability of the Dutch adaptation of the Psoriatic Arthritis Quality of Life (PsAQoL Questionnaire.

    Directory of Open Access Journals (Sweden)

    Freke Wink

    Full Text Available OBJECTIVE: The Psoriatic Arthritis Quality of Life (PsAQoL questionnaire is a disease- specific instrument developed to measure quality of life (QoL in patients with psoriatic arthritis (PsA. The aim of this study was to translate the measure into Dutch and to determine its psychometric properties. METHOD: Translation of the original English PsAQoL into Dutch was performed by bilingual and lay panel. Ten field-test interviews with PsA patients were performed to assess face and content validity. In total, 211 PsA patients were included in a test-retest postal survey to investigate the reliability and construct validity of the Dutch adaptation of the PsAQoL. The PsAQoL, Health Assessment Questionnaire (HAQ and Skindex-17 were administered on two different occasions approximately two weeks apart. RESULTS: The Dutch version of the PsAQoL was found to be relevant, understandable and easy to complete in only a few minutes. It correlated as expected with the HAQ (Spearman's ρ = 0.72 and the 2 subscales of the Skindex-17 (ρ = 0.40 for the psychosocial and ρ = 0.46 for the symptom scale. Furthermore, the measure had good internal consistency (Cronbach's α = 0.92 and test-retest reliability (ρ = 0.89. The PsAQoL was able to define groups of patients based on self-reported general health status, self-reported severity of PsA and flare of arthritis. Duration of PsA did not influence PsAQoL scores. CONCLUSIONS: The Dutch version of the PsAQoL is a valid and reliable questionnaire suitable for use in clinical or research settings to asses PsA-specific QoL.

  15. Low energy o-Ps-o-Ps elastic scattering using a simple model

    Energy Technology Data Exchange (ETDEWEB)

    Himanshu, Sharma [Veer Kunwar Singh Univ., Dept. of Physics, Bihar (India); Kiran, Kumari [R N College, P. G. Dept. of Physics, Bihar (India); Sumana, Chakraborty [Indian Association for the Cultivation of Science, Dept. of Theoretical Physics (India)

    2009-06-15

    A simple model is employed to investigate o-Ps-o-Ps (positronium-positronium) scattering at low energies. This model contains the effect of exchange explicitly and a model long range potential in the framework of static-exchange model. These two physical features are of key importance in Ps-Ps (atom-atom) scattering system. S-wave triplet-triplet and singlet-singlet scattering lengths and corresponding phase shifts up to the incident momentum k = 0.5 a.u. are in excellent agreement with those yielded by most elaborate and theoretically sound predictions. (authors)

  16. Generality of the 18-n Rule: Intermetallic Structural Chemistry Explained through Isolobal Analogies to Transition Metal Complexes.

    Science.gov (United States)

    Yannello, Vincent J; Fredrickson, Daniel C

    2015-12-07

    Intermetallic phases exhibit a vast structural diversity in which electron count is known to be one controlling factor. However, chemical bonding theory has yet to establish how electron counts and structure are interrelated for the majority of these compounds. Recently, a simple bonding picture for transition metal (T)-main group (E) intermetallics has begun to take shape based on isolobal analogies to molecular T complexes. This bonding picture is summarized in the 18-n rule: each T atom in a T-E intermetallic phase will need 18-n electrons to achieve a closed-shell 18-electron configuration, where n is the number of electron pairs it shares with other T atoms in multicenter interactions isolobal to T-T bonds. In this Article, we illustrate the generality of this rule with a survey over a wide range of T-E phases. First, we illustrate how three structural progressions with changing electron counts can be accounted for, both geometrically and electronically, with the 18-n rule: (1) the transition between the fluorite and complex β-FeSi2 types for TSi2 phases; (2) the sequence from the marcasite type to the arsenopyrite type and back to the marcasite type for TSb2 compounds; and (3) the evolution from the AuCu3 type to the ZrAl3 and TiAl3 types for TAl3 phases. We then turn to a broader survey of the applicability of the 18-n rule through a study of the following 34 binary structure types: PtHg4, CaF2 (fluorite), Fe3C, CoGa3, Co2Al5, Ru2B3, β-FeSi2, NiAs, Ni2Al3, Rh4Si5, CrSi2, Ir3Ga5, Mo3Al8, MnP, TiSi2, Ru2Sn3, TiAl3, MoSi2, CoSn, ZrAl3, CsCl, FeSi, AuCu3, ZrSi2, Mn2Hg5, FeS2 (oP6, marcasite), CoAs3 (skutterudite), PdSn2, CoSb2, Ir3Ge7, CuAl2, Re3Ge7, CrP2, and Mg2Ni. Through these analyses, the 18-n rule is established as a framework for interpreting the stability of 341 intermetallic phases and anticipating their properties.

  17. LS1 Report: PS beams are back!

    CERN Multimedia

    Katarina Anthony & Anaïs Schaeffer

    2014-01-01

    For the first time in over 15 months, there are beams back in the PS. Making their first tour of the accelerator today, 20 June, their injection marks the end of weeks of cold checkouts and hardware commissioning in the PS.   The CERN Control Centre (CCC) is back in business: people gather to restart the LHC injectors, today the PS. Since hardware commissioning was wrapped up on 23 May, the Operations Group (BE-OP) has been conducting cold checkouts on the PS. This involves switching on all of the machine's systems, verifying that they respond to commands by OP and ensuring they are calibrated to beam timings. "These verifications were done, in part, during the hardware commissioning dry runs," says Rende Steerenberg, PS section leader. "But the cold checkouts are on a much larger scale, as we act as if there is beam in the whole machine. We placed a full load on the controls system, cooling, networks, etc. in order to setup the accelerator in the most realis...

  18. Risk Management Capability Maturity and Performance of Complex Product and System (CoPS Projects with an Asian Perspective

    Directory of Open Access Journals (Sweden)

    Ren, Y.

    2014-07-01

    Full Text Available Complex Products and Systems (CoPS are high value, technology and engineering-intensive capital goods. The motivation of this study is the persistent high failure rate of CoPS projects, Asian CoPS provider’s weak capability and lack of specific research on CoPS risk management. This paper evaluates risk management maturity level of CoPS projects against a general CoPS risk management capability maturity model (RM-CMM developed by the authors. An Asian based survey was conducted to investigate the value of RM to project performance, and Asian (non-Japanese CoPS implementers’ perceived application of RM practices, their strengths and weaknesses. The survey result shows that higher RM maturity level leads to higher CoPS project performance. It also shows project complexity and uncertainty moderates the relationship between some RM practices and project performance, which implies that a contingency approach should be adopted to manage CoPS risks effectively. In addition, it shows that Asian CoPS implementers are weak in RM process and there are also rooms for improvement in the softer aspects of organizational capabilities and robustness.

  19. Evaluation of Questions in General Chemistry Textbooks According to the Form of the Questions and the Question-Answer Relationship (QAR): The Case of Intra-and Intermolecular Chemical Bonding

    Science.gov (United States)

    Pappa, Eleni T.; Tsaparlis, Georgios

    2011-01-01

    One way of checking to what extent instructional textbooks achieve their aim is to evaluate the questions they contain. In this work, we analyze the questions that are included in the chapters on chemical bonding of ten general chemistry textbooks. We study separately the questions on intra- and on intermolecular bonding, with the former…

  20. Chemistry Dashboard

    Science.gov (United States)

    The Chemistry Dashboard is part of a suite of dashboards developed by EPA to help evaluate the safety of chemicals. The Chemistry Dashboard provides access to a variety of information on over 700,000 chemicals currently in use.

  1. Inhibition of the integrin signal constitutes a mouse iPS cell niche.

    Science.gov (United States)

    Higuchi, Sayaka; Yoshina, Sawako; Mitani, Shohei

    2016-09-01

    Stem cells are regulated by their surrounding microenvironments, called niche, such as cell-cell interaction and extracellular matrix. Classically, feeder cells as a niche have been used in the culture of iPS cells from both the mouse and the human. However, the regulation mechanism of stem cells by feeder cells as a niche still have been partially unclear. In this study, we used three murine iPS cell lines, iPS-MEF-Ng-20D-17, iPS-MEF-Ng-178B-5 and iPS-MEF-Fb/Ng-440A-3, which were generated by different reprogramming methods. In general, these cell lines commonly need the feeder cells as a niche to culture. Recently, the effect of substrate stiffness is known in stem cell study. First, we focused on the mechanical properties of feeder cells, and then we speculated that feeder-less culture might be made possible by using molecules in place of the mechanical properties of the niche. Finally, we found that the combination of disintegrin (echistatin) and 2i (GSK3 inhibitor and MEK inhibitor) is a sufficient condition for three murine iPS culture. This novel method of mimicking the murine iPS cell niche may be useful to understand signaling pathways to maintain the pluripotency of stem cells. © 2016 The Authors. Development, Growth & Differentiation published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Developmental Biologists.

  2. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. These pictures show one of the magnets (no. 19) on the PS locomotive brought back into service for the removal and replacement operations.

  3. Combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, John

    1994-01-01

    An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....

  4. General Synthesis of Transition-Metal Oxide Hollow Nanospheres/Nitrogen-Doped Graphene Hybrids by Metal-Ammine Complex Chemistry for High-Performance Lithium-Ion Batteries.

    Science.gov (United States)

    Chen, Jiayuan; Wu, Xiaofeng; Gong, Yan; Wang, Pengfei; Li, Wenhui; Mo, Shengpeng; Peng, Shengpan; Tan, Qiangqiang; Chen, Yunfa

    2018-02-09

    We present a general and facile synthesis strategy, on the basis of metal-ammine complex chemistry, for synthesizing hollow transition-metal oxides (Co 3 O 4 , NiO, CuO-Cu 2 O, and ZnO)/nitrogen-doped graphene hybrids, potentially applied in high-performance lithium-ion batteries. The oxygen-containing functional groups of graphene oxide play a prerequisite role in the formation of hollow transition-metal oxides on graphene nanosheets, and a significant hollowing process occurs only when forming metal (Co 2+ , Ni 2+ , Cu 2+ , or Zn 2+ )-ammine complex ions. Moreover, the hollowing process is well correlated with the complexing capacity between metal ions and NH 3 molecules. The significant hollowing process occurs for strong metal-ammine complex ions including Co 2+ , Ni 2+ , Cu 2+ , and Zn 2+ ions, and no hollow structures formed for weak and/or noncomplex Mn 2+ and Fe 3+ ions. Simultaneously, this novel strategy can also achieve the direct doping of nitrogen atoms into the graphene framework. The electrochemical performance of two typical hollow Co 3 O 4 or NiO/nitrogen-doped graphene hybrids was evaluated by their use as anodic materials. It was demonstrated that these unique nanostructured hybrids, in contrast with the bare counterparts, solid transition-metal oxides/nitrogen-doped graphene hybrids, perform with significantly improved specific capacity, superior rate capability, and excellent capacity retention. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The effect of matching learning styles and instructional strategies on academic achievement and student enjoyment of science lessons in a high school general chemistry course

    Science.gov (United States)

    Fundi, Shaaban Kitindi

    This study explored the matching hypothesis by examining the effect of matching students' learning style preferences with teachers' instructional strategies on students' academic performance and lesson enjoyment in a high school general chemistry course. To achieve the study aims, the researcher utilized a single-participant study design with a baseline phase and four treatment phases. Determination of students' learning style preferences involved using the Visual, Audial, Read/Write, and Kinesthetic (VARK) Learning Style Inventory. During the one-week baseline phase, students received instruction using regular instructional strategies, followed by four treatment phases: visual intervention, audial intervention, read/write intervention, and a kinesthetic intervention. Each intervention phase lasted one week. During each phase, the researcher measured academic achievement using three teacher-created quiz scores. Student enjoyment was measured using the Test of Science-Related Attitudes (TOSRA). A total of 14 students completed the VARK Questionnaire. Of these, eight students (2 boys and 6 girls) exhibited a multimodal learning style were subsequently excluded from study participation. An additional student was excluded due to excessive absenteeism, leaving five students who completed all phases of the study. Results indicated that matching students' learning style preferences with teachers' instructional strategies did not improve students' academic performance as measured by teacher-created quizzes. However, weekly switching of the instructional strategies did improve student enjoyment of chemistry lessons. Student enjoyment increased for all participants in all intervention phases regardless of whether or not instruction matched students' learning style preferences compared to baseline phase. The results of this study do not support the matching hypothesis. The students in this study, preferred to learn with multiple teaching strategies. Alternating instructional

  6. avoiding general chemistry textbooks' misrepresentations

    African Journals Online (AJOL)

    IICBA01

    the proper definition of each of the terms analyzed, one problem is presented in order to exemplify the ..... the units on RT because ΔGo is an extensive quantity with units of energy, whereas RT is intensive with ..... definition of both the practical equilibrium constants and the thermodynamic equilibrium contant as well as ...

  7. Discovery of a general method of solving the Schrödinger and dirac equations that opens a way to accurately predictive quantum chemistry.

    Science.gov (United States)

    Nakatsuji, Hiroshi

    2012-09-18

    Just as Newtonian law governs classical physics, the Schrödinger equation (SE) and the relativistic Dirac equation (DE) rule the world of chemistry. So, if we can solve these equations accurately, we can use computation to predict chemistry precisely. However, for approximately 80 years after the discovery of these equations, chemists believed that they could not solve SE and DE for atoms and molecules that included many electrons. This Account reviews ideas developed over the past decade to further the goal of predictive quantum chemistry. Between 2000 and 2005, I discovered a general method of solving the SE and DE accurately. As a first inspiration, I formulated the structure of the exact wave function of the SE in a compact mathematical form. The explicit inclusion of the exact wave function's structure within the variational space allows for the calculation of the exact wave function as a solution of the variational method. Although this process sounds almost impossible, it is indeed possible, and I have published several formulations and applied them to solve the full configuration interaction (CI) with a very small number of variables. However, when I examined analytical solutions for atoms and molecules, the Hamiltonian integrals in their secular equations diverged. This singularity problem occurred in all atoms and molecules because it originates from the singularity of the Coulomb potential in their Hamiltonians. To overcome this problem, I first introduced the inverse SE and then the scaled SE. The latter simpler idea led to immediate and surprisingly accurate solution for the SEs of the hydrogen atom, helium atom, and hydrogen molecule. The free complement (FC) method, also called the free iterative CI (free ICI) method, was efficient for solving the SEs. In the FC method, the basis functions that span the exact wave function are produced by the Hamiltonian of the system and the zeroth-order wave function. These basis functions are called complement

  8. Positron Annihilation in the Bipositronium Ps2

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.; Frolov, Alexei M.

    2005-07-01

    The electron-positron-pair annihilation in the bipositronium PS2 is considered. In particular, the two-, three-, one- and zero-photon annihilation rates are determined to high accuracy. The corresponding analytical expressions are also presented. Also, a large number of bound state properties have been determined for this system.

  9. The 4 Ps as a Guiding Perspective

    Science.gov (United States)

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps perspective addresses immediate needs: to help institutions gain traction in their retention strategies by framing and reframing the challenges and the possible responses, by challenging some of the traditional mental models about retention that can distract or dilute those strategies, and by offering focus and coherence to institutional…

  10. 10th Anniversary P.S.

    CERN Multimedia

    Adams,J

    1969-01-01

    John Adams parle de la préhistoire du P.S. avec présentation des dias. Le DG B.Gregory prend la parole. Les organisateurs présentent sous la direction du "Prof.Ocktette"(?) un sketch très humoristique (p.e.existence de Quark etc.....)

  11. Back to work for the PS

    CERN Multimedia

    2006-01-01

    On 22 June, the PS's rotating machine started turning again for the first time since its enforced shutdown one month ago (see Bulletin No. 23-24/2006) - and the PS was back in operation the very next day! A team from Siemens worked their socks off, 6 days a week for one month (including public holidays), to repair the electrical power supply in collaboration with the AB/PO Group's Main Power Converters (MPC) Section. The generator's faulty rotor was dismantled and replaced by the renovated spare rotor. The multitude of electrical and mechanical connections together with the sheer weight of the rotor (80 tonnes) made this an extremely complex job. The AB/PO Group used the shutdown to test a back-up solution for the PS power supply. The accelerator was directly wired up to the 18 kV electrical network via a 13 MVA transformer, installed at the end of the 1970s but never used. This solution succeeded in bringing the PS back into operation but at limited energy and frequency. Just 14 GeV could be achieved, whic...

  12. Síntese de biodiesel: uma proposta contextualizada de experimento para laboratório de química geral Synthesis of biodiesel: a contextualized experiment proposal for the general chemistry laboratory

    Directory of Open Access Journals (Sweden)

    Roberto Rinaldi

    2007-10-01

    Full Text Available The contextualized understanding of concepts in Chemistry by students from other areas is a challenging task. In this experiment, the synthesis of biodiesel is done by base catalyzed transesterification of refined soy oil with methanol at room temperature and common glassware found in any chemistry laboratory. The proposal permits introducing several concepts, such as that of emulsion, viscosity and catalysis to illustrate an activity based on an actual problem. In this didactic approach, some common problems of biodiesel production, such as soap formation and phase separation, are introduced into the procedure in order to raise questions and motivate the students to participate in the experimental work and stimulate reflections about critical aspects of biodiesel production. This experiment was carried out in the first semester of 2006, in experimental general chemistry taken by physics and agricultural, civil and chemical engineering students of UNICAMP.

  13. A multiturn measurement system for the CERN PS

    CERN Document Server

    Angoletta, Maria Elena

    2002-01-01

    Multiturn beam position measurements on one or more pickups provide very important information needed to derive machine optics parameters. A variety of analyses is possible, such as determination of phase advance, detuning with amplitude, and most important, the exploration of phase space. In this paper we present a new multiturn acquisition system for the CERN proton synchrotron (CERN PS) based on a compact PCI fast digitiser and a new general object-oriented visualisation and analysis tool for the acquired multiturn data. (11 refs).

  14. Mathematics for physical chemistry

    CERN Document Server

    Mortimer, Robert G

    2013-01-01

    Mathematics for Physical Chemistry is the ideal supplementary text for practicing chemists and students who want to sharpen their mathematics skills while enrolled in general through physical chemistry courses. This book specifically emphasizes the use of mathematics in the context of physical chemistry, as opposed to being simply a mathematics text. This 4e includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The early chapters are constructed around a sequence of mathematical topics, wit

  15. Experiments in physical chemistry

    CERN Document Server

    Wilson, J M; Denaro, A R

    1968-01-01

    Experiments in Physical Chemistry, Second Edition provides a compilation of experiments concerning physical chemistry. This book illustrates the link between the theory and practice of physical chemistry. Organized into three parts, this edition begins with an overview of those experiments that generally have a simple theoretical background. Part II contains experiments that are associated with more advanced theory or more developed techniques, or which require a greater degree of experimental skill. Part III consists of experiments that are in the nature of investigations wherein these invest

  16. Efficient model chemistries for peptides. I. General framework and a study of the heterolevel approximation in RHF and MP2 with Pople split-valence basis sets.

    Science.gov (United States)

    Echenique, Pablo; Alonso, José Luis

    2008-07-15

    We present an exhaustive study of more than 250 ab initio potential energy surfaces (PESs) of the model dipeptide HCO-L-Ala-NH(2). The model chemistries (MCs) investigated are constructed as homo- and heterolevels involving possibly different RHF and MP2 calculations for the geometry and the energy. The basis sets used belong to a sample of 39 representants from Pople's split-valence families, ranging from the small 3-21G to the large 6-311++G(2df,2pd). The reference PES to which the rest are compared is the MP2/6-311++G(2df,2pd) homolevel, which, as far as we are aware, is the most accurate PES in the literature. All data sets have been analyzed according to a general framework, which can be extended to other complex problems and which captures the nearness concept in the space of MCs. The great number of MCs evaluated has allowed us to significantly explore this space and show that the correlation between accuracy and computational cost of the methods is imperfect, thus justifying a systematic search for the combination of features in a MC that is optimal to deal with peptides. Regarding the particular MCs studied, the most important conclusion is that the potentially very cost-saving heterolevel approximation is a very efficient one to describe the whole PES of HCO-L-Ala-NH(2). Finally, we show that, although RHF may be used to calculate the geometry if a MP2 single-point energy calculation follows, pure RHF//RHF homolevels are not recommendable for this problem. (c) 2008 Wiley Periodicals, Inc.

  17. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  18. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets (no.'s 6 and 19)and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Pictured here are members of the PS team with the replacement no. 6 magnet. From left to right: In the back row, Frédéric Roussel (Transport DBS), Yves Bernard (Transport DBS), Luc Moreno (Cegelec), Thierry Battimanza (Transport DBS), Raymond Brown (AB/ABP), Thomas Zickler (AT/MEL); at the front, Steven Southern (AT/VAC), Thierry Gaidon (Brun & Sorensen), Philippe Vidales (Cegelec), Daniel Aubert (Cegelec), Jerome Cachet (Transport DBS), Jose Manual Gomes de Faria (AT/MEL), Eric Page (AT/VAC).

  19. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators´ spring start-up to two weeks. Here we see one of the replacement magnets (no. 19) being prepared.

  20. The PS overcomes two serious magnet failures

    CERN Multimedia

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks.

  1. Motor-Generator Set, PS Main Supply

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    This is the "new" motor-generator set. It replaced the previous, original, one which had served from the PS start-up in 1959. Ordered in 1965, installed in 1967, it was brought into operation at the beginning of 1968. Regularly serviced and fitted with modern regulation and controls, it still serves at the time of writing (2006) and promises to serve for several more years, as a very much alive museum-piece. See also 6803016 and 0201010.

  2. Measuring target for the PS Booster

    CERN Multimedia

    1971-01-01

    The measuring target for the PS Booster (originally 800 MeV, now 1.4 GeV). It measures the size of the beam by destroying all particles with amplitudes greater than the size of the fork, the position and width of which are adjustable. The plunging time is only 20 ms and the acceleration at the tip of the fork reaches 90 g. The servo-controlled linear motor is shown detached from the mechanism. See also 7602008.

  3. Memories of the PS and of LEP

    CERN Document Server

    Steinberger, Jack

    2012-01-01

    The CERN PS, which started in 1959, and the Brookhaven AGS in 1960, represented an advance by a factor of more than five in the energy of proton accelerators, from the 5 GeV of the Berkeley Bevatron to about 30 GeV. These accelerators made possible the large progress in our understanding of particles and their interactions over the next two decades, culminating in the electroweak and QCD gauge theories.

  4. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Here we see one of the replacement magnets (no. 6) being prepared.

  5. Enhanced personal protection system for the PS

    CERN Multimedia

    Caroline Duc

    2013-01-01

    During the first long shutdown (LS1) a new safety system will be installed in the primary beam areas of the PS complex in order to bring the standard of personnel radiation protection at the PS into line with that of the LHC.   Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system. The LHC access control systems are state-of-the-art, whereas those of the injection chain accelerators were running the risk of becoming obsolete. For the past two years a project to upgrade the access and safety systems of the first links in the LHC accelerator chain has been underway to bring them into compliance with nuclear safety standards. These systems provide the personnel with automatic protection by limiting access to hazardous areas and by ensuring that nobody is present in the areas when the accelerator is in operation. By the end of 2013, the project teams will ha...

  6. Supplemental instruction in chemistry

    Science.gov (United States)

    Lundeberg, Mary A.

    This study was designed to measure some effects of supplemental instruction in chemistry. Supplemental instruction is a peer-led cooperative learning program that encourages students to develop conceptual understanding by articulating both understandings and misconceptions in a think-aloud fashion. Supplemental instruction was offered three hours weekly outside of class and lab time for students in four classes of General Organic and Biological Chemistry. Over a two-year period 108 students volunteered to participate in this program; 45 students did not participate. As measured by final grades in chemistry and responses to a questionnaire, supplemental instruction was effective in increasing students' achievement in chemistry. Further research is needed to determine the in-depth effects of supplemental instruction on students' learning, problem solving, and self-esteem.

  7. Current organic chemistry

    National Research Council Canada - National Science Library

    1997-01-01

    Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...

  8. Dynamic Combinatorial Chemistry

    DEFF Research Database (Denmark)

    Lisbjerg, Micke

    This thesis is divided into seven chapters, which can all be read individually. The first chapter, however, contains a general introduction to the chemistry used in the remaining six chapters, and it is therefore recommended to read chapter one before reading the other chapters. Chapter 1...... is a general introductory chapter for the whole thesis. The history and concepts of dynamic combinatorial chemistry are described, as are some of the new and intriguing results recently obtained. Finally, the properties of a broad range of hexameric macrocycles are described in detail. Chapter 2 gives...

  9. Psühhodramaatikud annavad Pärnus eksami

    Index Scriptorium Estoniae

    2008-01-01

    29. maist kuni 1. juunini kestab Pärnus psühhodraama konverents "Geeniuste kohtumine", kus rahvusvahelise koolituse läbinud annavad eksami. Ruuda Palmquist on psühhodraama kui teadusharu rajajaid Eestis. Pärnus on kohal Rootsi Moreno Instituudi juhataja, psühhodraama lavastaja Marc Treadwell

  10. Ion Exchange and Thin Layer Chromatographic Separation and Identification of Amino Acids in a Mixture: An Experiment for General Chemistry and Biotechnology Laboratories

    Science.gov (United States)

    Brunauer, Linda S.; Caslavka, Katelyn E.; Van Groningen, Karinne

    2014-01-01

    A multiday laboratory exercise is described that is suitable for first-year undergraduate chemistry, biochemistry, or biotechnology students. Students gain experience in performing chromatographic separations of biomolecules, in both a column and thin layer chromatography (TLC) format. Students chromatographically separate amino acids (AA) in an…

  11. Psychometric properties of the French translation of the reduced KOOS and HOOS (KOOS-PS and HOOS-PS)

    DEFF Research Database (Denmark)

    Ornetti, P; Perruccio, A V; Roos, E M

    2009-01-01

    OBJECTIVE: To evaluate the psychometric properties of the French KOOS physical function (KOOS-PS) and HOOS physical function (HOOS-PS), specifically its feasibility, reliability, construct validity, and responsiveness. METHODS: Consecutive outpatients consulting for primary knee or hip osteoarthr......OBJECTIVE: To evaluate the psychometric properties of the French KOOS physical function (KOOS-PS) and HOOS physical function (HOOS-PS), specifically its feasibility, reliability, construct validity, and responsiveness. METHODS: Consecutive outpatients consulting for primary knee or hip...

  12. Characterizing the successful student in general chemistry and physical science classes in terms of Jung's personality types as identified by the Myers-Briggs Type Indicator

    Science.gov (United States)

    Riley, Wayne David

    1998-11-01

    A student's success in a science class can depend upon previous experiences, motivation, and the level of interest in the subject. Since psychological type is intrinsic to a person's whole being, it can be influential upon the student's motivation and interests. Thus, a study of student psychological types versus the level of success in a class, as measured by a percentage, has potential to uncover certain personality characteristics which may be helpful to or which may hinder a student's learning environment. This study was initiated, using the Myers-Briggs Type Indicator, to evaluate any correlation between a student's personality type and his/her performance in a science class. A total of 1041 students from three classes: Chemistry 121/122, Chemistry 112, Physical Science 100, volunteered for the study. An analysis of variance (ANOVA) was used to determine the levels of significance among sixteen personality types' averages. The results reveal that for the Chemistry 1121/122 course, the average score of the INTJ personality type was 5.1 to 12.6 points higher than every other personality type. The ANOVA identifies 3 personality types with averages significantly below the INTJ at the p < 0.05 significance level. The ANOVA analysis for the Chemistry 112 course identified significances between student scores at p = 0.08. The significance level for the differences among scores for the Physical Science 100 course was determined at a level of p = 0.02. Significance levels for p < 0.05 and <0.01 were identified between several groups in this course. The data suggest, that although personality type may not predict a particular student's success in a science class, students with certain personality traits may be favored in a chemistry class due the structure of the instruction and the presentation of the subject matter.

  13. Evolving science enhanced with iPS

    Directory of Open Access Journals (Sweden)

    Editor

    2007-11-01

    Full Text Available Dear friends, Greetings from all in the team. With the stage set for online submissions and the review-response-revision-resubmission process standardized, we have come with the first regular issue and from now there will be quarterly issues of the journal. Since the starting of the JSRM in a short span there have been a lot of developments, which we would rather say as "evolutions" keeping in mind, the recent iPS! This evolution we would like you to see from a background of the various developments in the art and science of medicine throughout in the past three centuries. We have come across the era of investigative tools such as bamboo made laryngoscopes to era of vaccines and antibiotics followed by the era of revolutionary non-invasive procedures and recently the nano technology based drugs and now the iPS! Macro to Micro, but still more to go. All through the influence of the society, religions, philosophies have been playing a very important role in every step the science of biology moves ahead. Starting with the contraception, assisted reproduction then the gene modified plants....and now the embryonic stem cells! With the advent of the iPS, though the issues of oncogenes, teratoma yet to be ruled out, we have found there is a way which can bypass the ES cells! Hats off to those scientists who have burnt their midnight oil to have found this way out! The lesson we learn is to explore things with an open mind and continue to proceed further without spending much time fingers crossed. Yours sincerely,The Editorial team.

  14. Position pickup of the PS Booster

    CERN Multimedia

    CERN PhotoLab

    1975-01-01

    The beam position around the 4 rings of the PS Booster (originally 800 MeV, now 1.4 GeV), is measured with electrostatic pickups (PU). They consist of a ceramic cylinder forming part of the vacuum chamber, and, in order to save space, they are located inside the multipole lenses. The inside of the ceramic is coated with a metallic layer, into which the form of the electrodes was cut by computer-controlled micro-sandblasting. Each PU has a pair of horizontal and a pair of vertical electrodes, as well as a separate intensity-sensing circular electrode.

  15. Space charge studies in the PS

    CERN Document Server

    Asvesta, F; Damerau, H; Huschauer, A; Papaphilippou, Y; Serluca, M; Sterbini, G; Zisopoulos, P

    2017-01-01

    In this paper the results of Machine Development (MD)studies conducted at the CERN Proton Sychrotron (PS) arepresented. The main focus was the investigation of newworking points in an effort to characterize and potentiallyimprove the brightness for LHC-type beams in view of theLHC Injectors Upgrade (LIU). Various working points werecompared in terms of losses and emittance evolution. Sincespace charge and the resonances it excites are the main causefor emittance blow-up and losses, tunes close to excitedresonances were carefully studied. Mitigation techniques,such as bunch flattening using a double harmonic RF system,were also tested.

  16. Quantum chemistry

    CERN Document Server

    Lowe, John P

    1993-01-01

    Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,

  17. The physical basis of chemistry

    CERN Document Server

    Warren, Warren S

    2000-01-01

    If the text you're using for general chemistry seems to lack sufficient mathematics and physics in its presentation of classical mechanics, molecular structure, and statistics, this complementary science series title may be just what you're looking for. Written for the advanced lower-division undergraduate chemistry course, The Physical Basis of Chemistry, Second Edition, offers students an opportunity to understand and enrich the understanding of physical chemistry with some quantum mechanics, the Boltzmann distribution, and spectroscopy. Posed and answered are questions concerning eve

  18. PAN/PS elctrospun fibers for oil spill cleanup

    Science.gov (United States)

    Ying, Qiao; Lili, Zhao; Haixiang, Sun; Peng, Li

    2014-08-01

    A high-capacity oil sorbent was fabricated by electrospinning using PS/PAN blend. Morphology, contact angle and oil adsorption of PAN/PS fiber and PP nonwoven fabric were studied. It was found that the PAN/PS fiber had a smaller diameter than PP, and the maximum sorption capacities of the PAN/PS sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.7, 66.75, and 43.38 g/g, which were far higher than those of PP. The sorbent PS/PAN fiber showed a contact angle of water144.32° and diesel oil 0°. The sorption kinetics of PAN/PS and PP sorbent were also investigated. Compared with the commercial PP fabric, the PAN/PS fiber seems to have the ability to be used in oil-spill cleanup application.

  19. Chemotherapy and quality of life in NSCLC PS 2 patients

    DEFF Research Database (Denmark)

    Helbekkmo, Nina; Strøm, Hans H; Sundstrøm, Stein H

    2009-01-01

    INTRODUCTION: Nearly 40% of patients with advanced NSCLC are in performance status (PS) 2. These patients have a shorter life expectancy than PS 0/1 patients and they are underrepresented in clinical trials. Data on how platinum-based combination chemotherapy affects Health Related Quality of Life...... (HRQOL) of patients with PS 2 are scarce and the treatment of this important group of patients is controversial. METHODS: A national multicenter phase III study on platinum based chemotherapy to 432 advanced NSCLC patients included 123 patients with PS 2. To explore the treatment impact on HRQOL......: Whereas the demographic data at baseline were well balanced between the groups, the PS 2 patients had significantly worse function and more severe symptoms than the PS 0/1 patients. In response to combination chemotherapy, the PS 2 patients had a more profound improvement of global QOL, cognitive function...

  20. Materials Chemistry

    CERN Document Server

    Fahlman, Bradley D

    2011-01-01

    The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...

  1. Nuclear Chemistry.

    Science.gov (United States)

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  2. Chemistry: The Middle Kingdom

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 7. Chemistry: The Middle Kingdom. Gautam R Desiraju. General Article Volume 12 Issue 7 July 2007 pp 44-60. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/012/07/0044-0060. Keywords.

  3. Tunnelling Effects in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. Tunnelling Effects in Chemistry: Molecules in the Strange Quantum World. Sharmistha Karmakar Deepthi Jose Ayan Datta. General Article Volume 19 Issue 2 February 2014 pp 160-174 ...

  4. Nobel Prize in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 4. Nobel Prize in Chemistry – 2003 The Gateway for Perfect Health. S M Srideshikan S K Srivatsa. General Article Volume 9 Issue 4 April 2004 pp 61-70. Fulltext. Click here to view fulltext PDF. Permanent link:

  5. Arrows in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 1. Arrows in Chemistry. Abirami Lakshminarayanan. General Article Volume 15 Issue 1 January 2010 pp 51-63. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/015/01/0051-0063. Keywords. Arrows ...

  6. The PS Booster Fast Wire Scanner

    CERN Document Server

    Burger, S; Priestnall, K; Raich, U

    2003-01-01

    The very tight emittance budget for LHC type beams makes precise emittance measurements in the injector complex a necessity. The PS machine uses 2 fast wire scanners per transverse plane for emittance measurement of the circulating beams. In order to ease comparison the same type of wire scanners have been newly installed in the upstream machine, the PS Booster, where each of the 4 rings is equipped with 2 wire scanners measuring the horizontal and vertical profiles. Those wire scanners use new and more modern control and readout electronics featuring dedicated intelligent motor movement controllers, which relieves the very stringent real time constraints due to the very high speed of 20m/s. In order to be able to measure primary beams at the very low injection energy of the Booster (50MeV) secondary emission currents from the wire can be measured as well as secondary particle flows at higher primary particle energies during and after acceleration. The solution adopted for the control of the devices is descri...

  7. Sofrimento psíquico e trabalho

    Directory of Open Access Journals (Sweden)

    Sarah Rosa Salles Vieira

    2014-03-01

    Full Text Available O presente artigo aprofunda questões clínico-téoricas relacionadas especificamente ao trabalho docente e ao sofrimento psíquico a ele relacionado a partir da observação clínica e vivência grupal nos atendimentos terapêuticos ocupacionais realizados no Hospital do Servidor Público Estadual de São Paulo "Francisco Morato de Oliveira" (HSPE-FMO. Partindo dos estudos acerca da Psicopatologia do Trabalho de Christophe Dejours, do trabalho docente e do relato de um caso clínico, caracteriza a problemática do sofrimento no trabalho, os sistemas de defesa contra este sofrimento, a ameaça à subjetividade do próprio trabalhador, as representações e conflitos vivenciados no trabalho docente, bem como a relação aditiva estabelecida como uma estratégia inconsciente de sobrevivência psíquica.

  8. Green Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Collison, Melanie

    2011-05-15

    Green chemistry is the science of chemistry used in a way that will not use or create hazardous substances. Dr. Rui Resendes is working in this field at GreenCentre Canada, an offshoot of PARTEQ Innovations in Kingston, Ontario. GreenCentre's preliminary findings suggest their licensed product {sup S}witchable Solutions{sup ,} featuring 3 classes of solvents and a surfactant, may be useful in bitumen oil sands extraction.

  9. Modeling Alzheimer's disease with human induced pluripotent stem (iPS) cells.

    Science.gov (United States)

    Mungenast, Alison E; Siegert, Sandra; Tsai, Li-Huei

    2016-06-01

    In the last decade, induced pluripotent stem (iPS) cells have revolutionized the utility of human in vitro models of neurological disease. The iPS-derived and differentiated cells allow researchers to study the impact of a distinct cell type in health and disease as well as performing therapeutic drug screens on a human genetic background. In particular, clinical trials for Alzheimer's disease (AD) have been failing. Two of the potential reasons are first, the species gap involved in proceeding from initial discoveries in rodent models to human studies, and second, an unsatisfying patient stratification, meaning subgrouping patients based on the disease severity due to the lack of phenotypic and genetic markers. iPS cells overcome this obstacles and will improve our understanding of disease subtypes in AD. They allow researchers conducting in depth characterization of neural cells from both familial and sporadic AD patients as well as preclinical screens on human cells. In this review, we briefly outline the status quo of iPS cell research in neurological diseases along with the general advantages and pitfalls of these models. We summarize how genome-editing techniques such as CRISPR/Cas9 will allow researchers to reduce the problem of genomic variability inherent to human studies, followed by recent iPS cell studies relevant to AD. We then focus on current techniques for the differentiation of iPS cells into neural cell types that are relevant to AD research. Finally, we discuss how the generation of three-dimensional cell culture systems will be important for understanding AD phenotypes in a complex cellular milieu, and how both two- and three-dimensional iPS cell models can provide platforms for drug discovery and translational studies into the treatment of AD. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. KAJIAN INDUCED PLURIPOTENT STEMCELL (iPS (HARAPAN DAN TANTANGAN

    Directory of Open Access Journals (Sweden)

    Masagus Zainuri

    2014-05-01

    Full Text Available AbstractInduced Pluripotent Stemcell (iPS are adult cells which the genetic information in the nucleus of those cells being reprogrammed (reprogram by inserting exogenous pluripotential genes. The exogenous gene transduction is using vectors, such as lentivirus, retrovirus, or adenovirus, which suppressed the gene expression of the original cells, so they will express the transduced exogenous gene. Viral vectors are then used to reprogramming and producing iPS clones that are pluripotent. iPS derived from adult cells of patient with certain diseases will be used as a tool to study the mechanisms of those specific diseases and the effects of selected drugs against the diseases. Several previous studies have shown that iPS clones developed from specific genetic disease have its original genotype and retain the character of the response to the drug that similar as the original adult cells. Opportunities for the utilization of autologous iPS cell therapy in the future is wide open as expected iPS transplant will not be rejected when transplanted back to the patient. Behind all its potential, iPS production is still facing some problems to be applicable clinically. The use of viruses as vectors may cause problems due to virus gene sequences may be integrated into the genome of the DNA donor cell, thereby causing mutations of the iPS clones. Several subsequent studies have succeeded in replacing the use of viruses as vectors, but the level of efficiency obtained is still very low. Another problem that arises is that epigenetic changes may occur in iPS cultures. Many advanced research related to iPS may be developed in Indonesia and is necessary to improve the production efficiency of iPS and solve iPS clones epigenetic changes problems in the future.Keywords: iPS, pluripotency, transduction, transfection.AbstrakInduced Pluripotent Stemcell (iPS adalah sel somatic dewasa yang informasi genetika dalam inti selnyadiprogram ulang (reprogram dengan cara

  11. Comparison of molecular species of various transphosphatidylated phosphatidylserine (PS) with bovine cortex PS by mass spectrometry

    NARCIS (Netherlands)

    Chen, S.; Li, K.W.

    2008-01-01

    The exogenous introduction of a molecular species mixture of bovine cortex phosphatidylserine (BC-PS) has been claimed to improve memory function in subjects suffering from age-associated memory impairment and dementia. However, it has been also reported that oral administration of another molecular

  12. Migrating the CERN PS control system to IBM workstations

    CERN Document Server

    De Metz-Noblat, N

    1995-01-01

    The workstations used within the control system of the CERN PS accelerator complex are not produced any more. We had therefore to review the software primary used as user interface and we achieved a port to IBM workstations. We are also preparing the maintenance of this code for the next ten years with minimal staff. This implies a clear separation between general computing facilities, control system developments, and operation. In order to share our experience, we will try to summarize various aspects of this migration: - system installation principles used to speed-up error recovery time and long-term maintenance costs, - problems correlated with the coexistence of two different platforms during migration, - software problems due to the platform and operating system changes, - hidden dependencies from a specific manufacturer.

  13. PS main supply: motor-generator set.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    In picture 04 the motor is on the right in the background and the main view is of the generator. The peak power in each PS cycle drawn from the generator, up to 96 MW, is taken from the rotational kinetic energy of the rotor (a heavy-weight of 80 tons), which makes the rotational speed drop by only a few percent. The motor replenishes the average power of 2 to 4 MW. Photo 05: The motor-generator set is serviced every year and, in particular, bearings and slip-rings are carefully checked. To the left is the motor with its slip-rings visible. It has been detached from the axle and moved to the side, so that the rotor can be removed from the huge generator, looming at the right.

  14. Radiation Chemistry

    Science.gov (United States)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  15. Mathematics for physical chemistry

    CERN Document Server

    Mortimer, Robert G

    2005-01-01

    Mathematics for Physical Chemistry, Third Edition, is the ideal text for students and physical chemists who want to sharpen their mathematics skills. It can help prepare the reader for an undergraduate course, serve as a supplementary text for use during a course, or serve as a reference for graduate students and practicing chemists. The text concentrates on applications instead of theory, and, although the emphasis is on physical chemistry, it can also be useful in general chemistry courses. The Third Edition includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The first ten chapters are constructed around a sequence of mathematical topics, with a gradual progression into more advanced material. The final chapter discusses mathematical topics needed in the analysis of experimental data.* Numerous examples and problems interspersed throughout the presentations * Each extensive chapter contains a preview, objectives, and ...

  16. Polymer Chemistry

    Science.gov (United States)

    Williams, Martha; Roberson, Luke; Caraccio, Anne

    2010-01-01

    This viewgraph presentation describes new technologies in polymer and material chemistry that benefits NASA programs and missions. The topics include: 1) What are Polymers?; 2) History of Polymer Chemistry; 3) Composites/Materials Development at KSC; 4) Why Wiring; 5) Next Generation Wiring Materials; 6) Wire System Materials and Integration; 7) Self-Healing Wire Repair; 8) Smart Wiring Summary; 9) Fire and Polymers; 10) Aerogel Technology; 11) Aerogel Composites; 12) Aerogels for Oil Remediation; 13) KSC's Solution; 14) Chemochromic Hydrogen Sensors; 15) STS-130 and 131 Operations; 16) HyperPigment; 17) Antimicrobial Materials; 18) Conductive Inks Formulations for Multiple Applications; and 19) Testing and Processing Equipment.

  17. PS: A nonprocedural language with data types and modules

    Science.gov (United States)

    Gokhale, M. B.

    1986-01-01

    The Problem Specification (PS) nonprocedural language is a very high level language for algorithm specification. PS is suitable for nonprogrammers, who can specify a problem using mathematically-oriented equations; for expert programmers, who can prototype different versions of a software system for evaluation; and for those who wish to use specifications for portions (if not all) of a program. PS has data types and modules similar to Modula-2. The compiler generates C code. PS is first shown by example, and then efficiency issues in scheduling and code generation are discussed.

  18. Food carbohydrate chemistry

    National Research Council Canada - National Science Library

    Wrolstad, R. E

    2012-01-01

    .... Now in Food Carbohydrate Chemistry, author Wrolstad emphasizes the application of carbohydrate chemistry to understanding the chemistry, physical and functional properties of food carbohydrates...

  19. Significant steps in the evolution of analytical chemistry--is the today's analytical chemistry only chemistry?

    Science.gov (United States)

    Karayannis, Miltiades I; Efstathiou, Constantinos E

    2012-12-15

    In this review the history of chemistry and specifically the history and the significant steps of the evolution of analytical chemistry are presented. In chronological time spans, covering the ancient world, the middle ages, the period of the 19th century, and the three evolutional periods, from the verge of the 19th century to contemporary times, it is given information for the progress of chemistry and analytical chemistry. During this period, analytical chemistry moved gradually from its pure empirical nature to more rational scientific activities, transforming itself to an autonomous branch of chemistry and a separate discipline. It is also shown that analytical chemistry moved gradually from the status of exclusive serving the chemical science, towards serving, the environment, health, law, almost all areas of science and technology, and the overall society. Some recommendations are also directed to analytical chemistry educators concerning the indispensable nature of knowledge of classical analytical chemistry and the associated laboratory exercises and to analysts, in general, why it is important to use the chemical knowledge to make measurements on problems of everyday life. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Confectionary Chemistry.

    Science.gov (United States)

    Levine, Elise Hilf

    1996-01-01

    Presents activities and demonstrations that enable teachers to use various types of confections as tactile experiences to spark chemistry students' interest and generate enthusiasm for learning. Presents uses of candy in teaching about atomic structure, spontaneous nuclear decay, chemical formulas, fractoluminescence, the effect of a molecular…

  1. Chemistry Notes.

    Science.gov (United States)

    School Science Review, 1983

    1983-01-01

    Presents chemistry experiments, laboratory procedures, demonstrations, and classroom materials/activities. These include: experiments on colloids, processing of uranium ore, action of heat on carbonates; color test for phenols and aromatic amines; solvent properties of non-electrolytes; stereoscopic applications/methods; a valency balance;…

  2. LEADIR-PS: providing unprecedented SMR safety and economics

    Energy Technology Data Exchange (ETDEWEB)

    Hart, R.S., E-mail: N2i2@xplornet.ca [Northern Nuclear Industries Incorporated, Cambridge, ON (Canada)

    2015-07-01

    Northern Nuclear Industries Incorporated (N{sup 2} I{sup 2}) is developing Small Modular Reactors (SMRs) called LEADIR-PS, an acronym for LEAD-cooled Integral Reactor-Passively Safe. LEADIR-PS integrates proven technologies including TRISO fuel, Pebble Bed core and graphite moderator, with molten lead coolant in an integral pool type reactor configuration to achieve unprecedented safety and economics. Plants under development are LEADIR-PS30, producing 30 MWth, LEADIR-PS100 producing 100 MWth and LEADIR-PS300 producing 300 MWth that are focused on serving the energy demands of areas with a small electrical grid and/or process heat applications. A plant consisting of six LEADIR-PS300 reactor modules serving a common turbine-generator, called the LEADIR-PS Six-Pack, is focused on serving areas with higher energy demands and a robust electricity grid. The Gen{sup +} I LEADIR-PS plants are inherently/passively safe. There is no potential for a Loss Of Coolant Accident, a reactivity transient without shutdown, a loss of heat sink, or hydrogen generation. No active systems or operator actions are required to assure safety. The unprecedented safety of LEADIR-PS reactors avoids large exclusion radius and demanding evacuation plan requirements. LEADIR-PS, with steam conditions of 370 {sup o}C and 12 MPa can serve over 85% of the world's non-transportation process heat demands. In Canada, the electricity and process heat demands, ranging from those of remote communities and the oil sands to densely populated areas can be served by LEADIR-PS. (author)

  3. Handbook of relativistic quantum chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenjian (ed.) [Peking Univ., Beijing (China). Center for Computational Science and Engineering

    2017-03-01

    This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.

  4. Student academic achievement in college chemistry

    Science.gov (United States)

    Tabibzadeh, Kiana S.

    General Chemistry is required for variety of baccalaureate degrees, including all medical related fields, engineering, and science majors. Depending on the institution, the prerequisite requirement for college level General Chemistry varies. The success rate for this course is low. The purpose of this study is to examine the factors influencing student academic achievement and retention in General Chemistry at the college level. In this study student achievement is defined by those students who earned grades of "C" or better. The dissertation contains in-depth studies on influence of Intermediate Algebra as a prerequisite compared to Fundamental Chemistry for student academic achievement and student retention in college General Chemistry. In addition the study examined the extent and manner in which student self-efficacy influences student academic achievement in college level General Chemistry. The sample for this part of the study is 144 students enrolled in first semester college level General Chemistry. Student surveys determined student self-efficacy level. The statistical analyses of study demonstrated that Fundamental Chemistry is a better prerequisite for student academic achievement and student retention. The study also found that student self-efficacy has no influence on student academic achievement. The significance of this study will be to provide data for the purpose of establishing a uniform and most suitable prerequisite for college level General Chemistry. Finally the variables identified to influence student academic achievement and enhance student retention will support educators' mission to maximize the students' ability to complete their educational goal at institutions of higher education.

  5. The HARP detector at the CERN PS

    CERN Document Server

    Catanesi, M G; Radicioni, E; Simone, S; Edgecock, R; Ellis, M; Robbins, S; Soler, F J P; Gößling, C; Mass, M; Bunyatov, S; Chukanov, A; Klimov, O; Krasin, I; Krasnoperov, A; Kustov, D; Popov, B; Serdiouk, V; Tereshchenko, V; Carassiti, V; Di Capua, E; Evangelisti, F; Vidal-Sitjes, G; Artamonov, A; Arce, P; Brocard, R; Decreuse, G; Friend, B; Giani, S; Gilardoni, S; Gorbunov, p; Grant, A; Grossheim, A; Gruber, P; Ivanchenko, V; Legrand, J C; Kayis-Topaksu,A; Panman, P; Papadopoulos, I; Pasternak, J; Chernyaev, E; Tsukerman, I; van der Vlugt, R; Veenhof, R; Wiebusch, C; Zucchelli, P; Blondel, A; Borghi, S; Campanelli, M; Cervera-Villanueva, A; Morone, M C; Prior, G; Schroeter, R; Kato, I; Gastaldi, Ugo; Mills, G B; Graulich, J S; Grégoire, G; Bonesini, M; Chignoli, F; Ferri, F; Paleari, F; Kirsanov, M; Postoev, V; Bagulya A; Grichine, V; Polukhina, N; Palladino, V; Coney, L; Schmitz, D; Barr, G; De Santo, A; Pattison, C; Zuber, K; Barichello, G; Bobisut, F; Gibin, D; Guglielmi, A; Laveder, M; Menegolli, A; Mezzetto M; Pepato, Adriano; Dumarchez, J; Troquereau, S; Vannucci, F; Dore, U; Iaciofano, A; Lobello, M; Marinilli, F; Orestano, D; Panayotov, D; Pasquali, M; Pastore, F; Tonazzo, A; Tortora, L; Booth, C; Buttar, C; Hodgson, P; Howlett, L; Nicholson, R; Bogomilovw, M; Burin, K; Chizhov, M; Kolev, D; Petev, P; Rusinov, I; Tsenov, R; Piperov, S; Temnikov, P; Apollonio, M; Chimenti, P; Giannini, G; Santin, G; Burguet-Castell, J; Gómez-Cadenas, J J; Novella, P; Sorel, M; Tornero, A

    2007-01-01

    HARP is a high-statistics, large solid angle experiment to measure hadron production using proton and pion beams with momenta between 1.5 and 15 GeV/c impinging on many different solid and liquid targets from low to high Z. The experiment, located in the T9 beam of the CERN PS, took data in 2001 and 2002. For the measurement of momenta of produced particles and for the identification of particle types, the experiment includes a large-angle spectrometer, based on a Time Projection Chamber and a system of Resistive Plate Chambers, and a forward spectrometer equipped with a set of large drift chambers, a threshold Cherenkov detector, a time-of-flight wall and an electromagnetic calorimeter. The large angle system uses a solenoidal magnet, while the forward spectrometer is based on a dipole magnet. Redundancy in particle identification has been sought, to enable the cross-calibration of efficiencies and to obtain a few percent overall accuracy in the cross-section measurements. Detector construction, operation an...

  6. Interleaving of beam lines inside the PS tunnel

    CERN Multimedia

    1983-01-01

    View against the direction of the proton beams. The PS ring (section 26) is on the left. The injection tunnel for LEAR leaving from here has increased the trafic in this already busy area where the two Linacs and the transfer tunnel leading to the SPS, ISR and AA join the PS ring (cf. photo 7802260, 7802261, Annual Report 1981, p. 89, fig. 12).

  7. Modulation of enzymatic PS synthesis by liposome membrane composition.

    Science.gov (United States)

    Pinsolle, Alexandre; Roy, Philippe; Cansell, Maud

    2014-03-01

    Phosphatidylserine (PS) is a phospholipid known to exert important physiological roles in humans. However, this phospholipid (PL) is poorly available as a natural source and hardly produced by the chemical route. In this work, PS was obtained by transphosphatidylation using phospholipase D (PLD) and PL self-assembled into liposomes as the substrates. The aim was to better understand how the liposome membrane composition could modulate PS yield. Three lecithins were used as PL substrates, one originated from a marine source providing a high amount of n-3 polyunsaturated fatty acids, and two issued from soya differing in their phosphatidylcholine (PC) content. Different parameters such as Ca(2+) content, enzyme and L-serine concentrations modulated PS synthesis. The presence of Ca(2+) increased PS conversion yield. The alcohol acceptor (L-serine) concentration positively acted on PL conversion, by governing the equilibrium between transphosphatidylation and hydrolysis. Beside these specific reaction conditions, it was demonstrated that the membrane composition of the liposomes modulated PS synthesis. A direct correlation between PS accumulation and the amount of cholesterol or α-tocopherol incorporated into the soya lecithins was observed. This result was interpreted in terms of "head" spacers promoting PLD transphosphatidylation. On the whole, this work provided key parameters for the formulation of liposomes using enzymatic PLD technology, to produce lecithins enriched in different proportions of PS and esterified with various types of fatty acids depending on the initial lecithin source. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Spectroscopic Classification of PS16chs with SOAR/Goodman

    Science.gov (United States)

    Miller, J. A.; Hounsell, R. A.; Pan, Y.-C.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-05-01

    We report the classification of PS16chs from spectroscopic observation with the Goodman spectrograph on the SOAR telescope. The observation was made on 2016 May 08 UT. We classify PS16chs as a SN Ia near maximum light at z = 0.19.

  9. Motor-Generator powering the PS (Proton Synchrotron) main magnets

    CERN Multimedia

    1983-01-01

    This motor-generator,30 MW peak, 1500 r.p.m.,pulsed power supply for the PS main magnet replaced in 1968 the initial 3000 r.p.m. motor-generator-flywheel set which had served from the PS start-up in 1959 until end 1967. See also photo 8302337 and its abstract.

  10. Transfer line TT70 (electrons from PS to SPS)

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    As injectors for LEP, PS and SPS had to be converted to the acceleration of electrons and positrons. So far, only positively charged particles had been transferred from the PS to the SPS, for the negatively charged electrons a new transfer line, TT70, had to be built. Due to the difference in level of the two machines, the transfer line slopes and tilts.

  11. Psühhodraama - spontaansuse kool / Taimi Elenurm

    Index Scriptorium Estoniae

    Elenurm, Taimi

    2010-01-01

    Viinis ja New Yorgis tegutsenud psühhiaatri Jakob Levy Moreno loodud psühhodraamast, mis võimaldab rollimängu kaudu näha ennast läbi teiste silmade, aga ka vabaneda pingetest andes võimaluse käituda teisiti kui tavaelus

  12. Successful online learning – the five Ps

    Directory of Open Access Journals (Sweden)

    Jim FLOOD

    2004-04-01

    Full Text Available Successful online learning – the five Ps Jim FLOOD E-learning Consultant-UK jimflood@btinternet.com Key learning points • An important aspect of design for online learning is visual ergonomics. • Learning theories offer poor predictive power in terms of how learners work and learn. • Success at learning is closely related to emotional engagement–and learning designers tend to ignore this aspect. • Online learning poses a challenging experience for learners–and they need support to cope with it. • A key goal to achieve Praxis – being able to put learning into practice. Many of you will be familiar with the three (or more Ps of marketing and even if not, as trainers or teachers you are likely to have used mnemonics as an aid to retention and recall. Mnemonics are especially useful when you need to get the key points to ‘stick’ in the minds of your audience. With this in mind I offer you the 5 Ps of online learning: Presentation, Pedagogy, Promotion, Preparation and Props. What I offer is not new; in fact much of it results from the eleven years of online teaching and learning at The Open University, the £22 million it has spent on research and evaluation 1, and the worldwide community that have been sharing experience in recent years. You can therefore consider these 5 Ps to be a convenient re-packing of the information and experience that can be found in abundance on the Internet. Presentation Good graphic design appeals to the subtle process by which the brain processes information and, as a result, we decide if we like the ‘look and feel’ of a visual environment. Part of liking this ‘look and feel’ is the way the text and pictorial layout can appear inviting and encouraging–a vital aspect of any online learning environment. Another aspect of presentation is how the text reads in terms of engaging the learner and introducing the story to be told–as well as being written in clear and concise English When browsing through books

  13. Cocrystal Controlled Solid-State Synthesis: A Green Chemistry Experiment for Undergraduate Organic Chemistry

    Science.gov (United States)

    Cheney, Miranda L.; Zaworotko, Michael J.; Beaton, Steve; Singer, Robert D.

    2008-01-01

    Green chemistry has become an important area of concern for all chemists from practitioners in the pharmaceutical industry to professors and the students they teach and is now being incorporated into lectures of general and organic chemistry courses. However, there are relatively few green chemistry experiments that are easily incorporated into…

  14. Telomere reprogramming and maintenance in porcine iPS cells.

    Directory of Open Access Journals (Sweden)

    Guangzhen Ji

    Full Text Available Telomere reprogramming and silencing of exogenous genes have been demonstrated in mouse and human induced pluripotent stem cells (iPS cells. Pigs have the potential to provide xenotransplant for humans, and to model and test human diseases. We investigated the telomere length and maintenance in porcine iPS cells generated and cultured under various conditions. Telomere lengths vary among different porcine iPS cell lines, some with telomere elongation and maintenance, and others telomere shortening. Porcine iPS cells with sufficient telomere length maintenance show the ability to differentiate in vivo by teratoma formation test. IPS cells with short or dysfunctional telomeres exhibit reduced ability to form teratomas. Moreover, insufficient telomerase and incomplete telomere reprogramming and/or maintenance link to sustained activation of exogenous genes in porcine iPS cells. In contrast, porcine iPS cells with reduced expression of exogenous genes or partial exogene silencing exhibit insufficient activation of endogenous pluripotent genes and telomerase genes, accompanied by telomere shortening with increasing passages. Moreover, telomere doublets, telomere sister chromatid exchanges and t-circles that presumably are involved in telomere lengthening by recombination also are found in porcine iPS cells. These data suggest that both telomerase-dependent and telomerase-independent mechanisms are involved in telomere reprogramming during induction and passages of porcine iPS cells, but these are insufficient, resulting in increased telomere damage and shortening, and chromosomal instability. Active exogenes might compensate for insufficient activation of endogenous genes and incomplete telomere reprogramming and maintenance of porcine iPS cells. Further understanding of telomere reprogramming and maintenance may help improve the quality of porcine iPS cells.

  15. Telomere reprogramming and maintenance in porcine iPS cells.

    Science.gov (United States)

    Ji, Guangzhen; Ruan, Weimin; Liu, Kai; Wang, Fang; Sakellariou, Despoina; Chen, Jijun; Yang, Yang; Okuka, Maja; Han, Jianyong; Liu, Zhonghua; Lai, Liangxue; Gagos, Sarantis; Xiao, Lei; Deng, Hongkui; Li, Ning; Liu, Lin

    2013-01-01

    Telomere reprogramming and silencing of exogenous genes have been demonstrated in mouse and human induced pluripotent stem cells (iPS cells). Pigs have the potential to provide xenotransplant for humans, and to model and test human diseases. We investigated the telomere length and maintenance in porcine iPS cells generated and cultured under various conditions. Telomere lengths vary among different porcine iPS cell lines, some with telomere elongation and maintenance, and others telomere shortening. Porcine iPS cells with sufficient telomere length maintenance show the ability to differentiate in vivo by teratoma formation test. IPS cells with short or dysfunctional telomeres exhibit reduced ability to form teratomas. Moreover, insufficient telomerase and incomplete telomere reprogramming and/or maintenance link to sustained activation of exogenous genes in porcine iPS cells. In contrast, porcine iPS cells with reduced expression of exogenous genes or partial exogene silencing exhibit insufficient activation of endogenous pluripotent genes and telomerase genes, accompanied by telomere shortening with increasing passages. Moreover, telomere doublets, telomere sister chromatid exchanges and t-circles that presumably are involved in telomere lengthening by recombination also are found in porcine iPS cells. These data suggest that both telomerase-dependent and telomerase-independent mechanisms are involved in telomere reprogramming during induction and passages of porcine iPS cells, but these are insufficient, resulting in increased telomere damage and shortening, and chromosomal instability. Active exogenes might compensate for insufficient activation of endogenous genes and incomplete telomere reprogramming and maintenance of porcine iPS cells. Further understanding of telomere reprogramming and maintenance may help improve the quality of porcine iPS cells.

  16. Supramolecular analytical chemistry.

    Science.gov (United States)

    Anslyn, Eric V

    2007-02-02

    A large fraction of the field of supramolecular chemistry has focused in previous decades upon the study and use of synthetic receptors as a means of mimicking natural receptors. Recently, the demand for synthetic receptors is rapidly increasing within the analytical sciences. These classes of receptors are finding uses in simple indicator chemistry, cellular imaging, and enantiomeric excess analysis, while also being involved in various truly practical assays of bodily fluids. Moreover, one of the most promising areas for the use of synthetic receptors is in the arena of differential sensing. Although many synthetic receptors have been shown to yield exquisite selectivities, in general, this class of receptor suffers from cross-reactivities. Yet, cross-reactivity is an attribute that is crucial to the success of differential sensing schemes. Therefore, both selective and nonselective synthetic receptors are finding uses in analytical applications. Hence, a field of chemistry that herein is entitled "Supramolecular Analytical Chemistry" is emerging, and is predicted to undergo increasingly rapid growth in the near future.

  17. Overview of PWR chemistry options

    Energy Technology Data Exchange (ETDEWEB)

    Nordmann, F.; Stutzmann, A.; Bretelle, J.L. [Electricite de France, Central Labs. (France)

    2002-07-01

    EDF Central Laboratories, in charge of engineering in chemistry, of defining the chemistry specifications and studying the operation feedback and improvement for 58 PWR units, have the opportunity to evaluate many options of operation developed and applied all around the world. Thanks to these international relationships and to the benefit of a large feedback from many units, some general evaluation of the various options is discussed in this paper. (authors)

  18. Shallow PS-logging by high frequency wave; Koshuha wo mochiita senbu PS kenso

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, A.; Miyazawa, M.; Azuma, H. [OYO Corp., Tokyo (Japan)

    1996-05-01

    This paper describes the following matters on down-hole PS logging in shallow subsurface. Determining an elastic wave velocity structure in shallow subsurface with high accuracy by using down-hole PS logging requires reduction of errors in reading travel time. Therefore, a high-frequency vibration source was fabricated with an objective to raise frequencies of waves used for the measurement. Measurements were made on two holes, A and B, at a measurement interval of 0.5 m, whereas at the hole A a measurement was performed simultaneously by using a normal type (low-frequency) vibration source. A spectral analysis on the waveform record revealed that the frequencies with each vibration source were 127 Hz and 27 Hz for the hole A, 115 Hz for the hole B, and the S/N ratio was all the same for both holes. When the high-frequency vibration source was used, the velocity was determined at accuracy of 5% over the whole length of the shallow section. When the low-frequency vibration source was used, sections with the velocity determining error greater than 5% were found, and it was not possible to derive the velocity structure in the shallow subsurface in fine segments. 3 refs., 8 figs., 2 tabs.

  19. Theoretical chemistry periodicities in chemistry and biology

    CERN Document Server

    Eyring, Henry

    1978-01-01

    Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

  20. Overview of the Moral Status of iPS Cells.

    Science.gov (United States)

    Martinho, Andreia Martins

    2016-07-01

    The production of induced pluripotent stem (iPS) cells in 2006 by Takahashi and Yamanaka was a major breakthrough in stem cell research. IPS cells technology holds great promise for cell therapy, disease modelling, and drug testing, but it poses ethical questions concerning the moral status of somatic cells, which can re-gain pluripotency (iPS cells). This article provides an overview of the arguments that substantiate the debate on the moral assessment of iPS cells: potentiality argument; relational properties/standard view; and genetic basis for moral status.

  1. Interstellar chemistry

    Science.gov (United States)

    Klemperer, William

    2006-01-01

    In the past half century, radioastronomy has changed our perception and understanding of the universe. In this issue of PNAS, the molecular chemistry directly observed within the galaxy is discussed. For the most part, the description of the molecular transformations requires specific kinetic schemes rather than chemical thermodynamics. Ionization of the very abundant molecular hydrogen and atomic helium followed by their secondary reactions is discussed. The rich variety of organic species observed is a challenge for complete understanding. The role and nature of reactions involving grain surfaces as well as new spectroscopic observations of interstellar and circumstellar regions are topics presented in this special feature. PMID:16894148

  2. Basidiomycete DyPs: Genomic diversity, structural-functional aspects, reaction mechanism and environmental significance.

    Science.gov (United States)

    Linde, Dolores; Ruiz-Dueñas, Francisco J; Fernández-Fueyo, Elena; Guallar, Victor; Hammel, Kenneth E; Pogni, Rebecca; Martínez, Angel T

    2015-05-15

    The first enzyme with dye-decolorizing peroxidase (DyP) activity was described in 1999 from an arthroconidial culture of the fungus Bjerkandera adusta. However, the first DyP sequence had been deposited three years before, as a peroxidase gene from a culture of an unidentified fungus of the family Polyporaceae (probably Irpex lacteus). Since the first description, fewer than ten basidiomycete DyPs have been purified and characterized, but a large number of sequences are available from genomes. DyPs share a general fold and heme location with chlorite dismutases and other DyP-type related proteins (such as Escherichia coli EfeB), forming the CDE superfamily. Taking into account the lack of an evolutionary relationship with the catalase-peroxidase superfamily, the observed heme pocket similarities must be considered as a convergent type of evolution to provide similar reactivity to the enzyme cofactor. Studies on the Auricularia auricula-judae DyP showed that high-turnover oxidation of anthraquinone type and other DyP substrates occurs via long-range electron transfer from an exposed tryptophan (Trp377, conserved in most basidiomycete DyPs), whose catalytic radical was identified in the H2O2-activated enzyme. The existence of accessory oxidation sites in DyP is suggested by the residual activity observed after site-directed mutagenesis of the above tryptophan. DyP degradation of substituted anthraquinone dyes (such as Reactive Blue 5) most probably proceeds via typical one-electron peroxidase oxidations and product breakdown without a DyP-catalyzed hydrolase reaction. Although various DyPs are able to break down phenolic lignin model dimers, and basidiomycete DyPs also present marginal activity on nonphenolic dimers, a significant contribution to lignin degradation is unlikely because of the low activity on high redox-potential substrates. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Chemistry of naphthalene diimides.

    Science.gov (United States)

    Bhosale, Sheshanath V; Jani, Chintan H; Langford, Steven J

    2008-02-01

    This tutorial review surveys recent developments in the chemistry of naphthalene diimides (NDIs) and explores their application in the fields of material and supramolecular science. It begins with a discussion of their general uses, methods of syntheses and their electronic and spectroscopic properties. Of interest to their application in the fields of conducting thin films and molecular sensors is the structure-function relationships that exist either as co-components of supramolecular ensembles as in the case of "nanotubes", or as the sole components in molecular wires. Also discussed are advances in NDI research within the areas of energy and electron transfer (covalent and non-covalent systems) and in host-guest chemistry including foldamer, mechanically-interlocked and ligand-gated ion channel examples. Finally, we explore the developments in the recent field of core-substituted NDIs, their photophysical properties and applications in artificial photosynthesis. We conclude with our views on the prospects of NDIs for future research endeavours.

  4. Quo vadis, analytical chemistry?

    Science.gov (United States)

    Valcárcel, Miguel

    2016-01-01

    This paper presents an open, personal, fresh approach to the future of Analytical Chemistry in the context of the deep changes Science and Technology are anticipated to experience. Its main aim is to challenge young analytical chemists because the future of our scientific discipline is in their hands. A description of not completely accurate overall conceptions of our discipline, both past and present, to be avoided is followed by a flexible, integral definition of Analytical Chemistry and its cornerstones (viz., aims and objectives, quality trade-offs, the third basic analytical reference, the information hierarchy, social responsibility, independent research, transfer of knowledge and technology, interfaces to other scientific-technical disciplines, and well-oriented education). Obsolete paradigms, and more accurate general and specific that can be expected to provide the framework for our discipline in the coming years are described. Finally, the three possible responses of analytical chemists to the proposed changes in our discipline are discussed.

  5. Benchmarking Problems Used in Second Year Level Organic Chemistry Instruction

    Science.gov (United States)

    Raker, Jeffrey R.; Towns, Marcy H.

    2010-01-01

    Investigations of the problem types used in college-level general chemistry examinations have been reported in this Journal and were first reported in the "Journal of Chemical Education" in 1924. This study extends the findings from general chemistry to the problems of four college-level organic chemistry courses. Three problem…

  6. PS buildings : reinforced concrete structure for shielding "bridge" pillar

    CERN Multimedia

    CERN PhotoLab

    1956-01-01

    The PS ring traverses the region between the experimental halls South and North (buildings Nos 150 and 151) under massive bridge-shaped concrete beams. This pillar stands at the S-W end of the structure.

  7. Study of Value Co-Creation in CoPS

    OpenAIRE

    Mingli Zhang; Jianhua Ye

    2013-01-01

    Value co-creation is associated with specific investment in the context of CoPS. The feature of CoPS decides that the study of co-creation cannot execute without regarding asset specificity. This study considers that value co-creation will be associated with specific value, which is outcome of relationship value and asset specificity. Supplier and customer have a close relation, which conducts to specific investment and then it turns to obstacle for competitors. Trust, commitment and satisfac...

  8. Motor-generator set of the PS main supply

    CERN Multimedia

    Photographic Service; CERN PhotoLab

    1968-01-01

    Already in 1964, the PS improvement programme included a new main magnet supply with more power for the longer cycles needed for slow extraction at the full energy of 26 GeV. This motor-generator set was installed in 1967 and took up service at the beginning of 1968. Regularly serviced and fitted with modern electronic regulation, it pulses the PS to this day.

  9. The Libera as a PS orbit measurement system building block

    CERN Document Server

    Belleman, J M; CERN. Geneva. AB Department

    2005-01-01

    During the year 2004, extensive tests using a Libera data processor have been made in order to study its suitability as a building block for a complete PS trajectory and orbit measurement system. The Libera consists of four fast 12-bits ADCs, a Virtex II Pro FPGA and a large memory. This note presents some of the results of the analysis of acquisitions made on a position pick-up in the CERN PS.

  10. DiPS: A Unifying Approach for developing System Software

    OpenAIRE

    Michiels, Sam; Matthijs, Frank; Walravens, Dirk; Verbaeten, Pierre

    2002-01-01

    In this paper we unify three essential features for flexible system software: a component oriented approach, self-adaptation and separation of concerns.We propose DiPS (Distrinet Protocol Stack), a component framework, which offers components, an anonymous interaction model and connectors to handle non-functional aspects such as concurrency. DiPS has effectively been used in industrial protocol stacks and device drivers.

  11. The new heart of the PS is beating strongly

    CERN Document Server

    Corinne Pralavorio

    2011-01-01

    The PS has resumed operation with a brand new electrical power system called POPS; this enormous system comprising power electronics and capacitors is crucial because if it broke down practically no particles would be able to circulate at CERN. As soon as it started, POPS passed all the tests with flying colours and is now pulsing at full power.   The new PS power system is made up of 6 containers, each with 60 tonnes of capacitors and 8 power converters. The date 11/02/11 will always be remembered with affection by the engineers in the Electrical Power Converters Group. At 11:11 in the morning (no joke), the first beams powered by the new system began to circulate in the PS. The cutely-named POPS (POwer for PS) took over from the old rotating machine that had been working since 1968. From now on it will be POPS that supplies the PS main magnets with the electrical pulses needed to accelerate the beams for the LHC and all CERN's other facilities. The system is crucial as the PS is one of the lyn...

  12. The PS will soon be back in operation

    CERN Multimedia

    2006-01-01

    The PS's power supply system is undergoing repairs for the accelerator to restart on 26 June. The AB Department's Power Converter Group is working flat out with Siemens to return the PS's power supply system to working order. A problem appeared on the insulation of the power cables of the rotor of the rotating machine (photo) which supplies power to the PS magnets. To prevent more significant damage to the rotating machine, the AB Department, with the approval of the CERN Management, decided to shut down the PS which had started running on 15 May. Everything is being done to restart the accelerator on 26 June. The PS's rotating machine comprises a motor coupled to a generator. The generator's rotor acts like a flywheel, supplying high-power pulses of 40 to 50 megawatts to the PS magnets. The 6 megawatt motor drives the installation at 1000 revolutions per minute and compensates only for variations in speed. It is an essential interface since it would be hard to imagine connecting such an electrical charge, p...

  13. iPS-Cinderella Story in Cell Biology

    Directory of Open Access Journals (Sweden)

    Editorial

    2010-01-01

    Full Text Available As we step through the frontiers of modern Science, we are all witnesses to the Cinderella story repeating itself in the form of the iPS. The process of re-programming adult somatic cells to derive Induced Pluripotent stem cells (iPS with the wand of transcription factors and then differentiating them back to adult somatic cells resembles the transformation of Cinderella from a Cinder girl to princess and back to a Cinder girl after the ball; but the iPS-Cinderella is the most fascinating thing ever in cell biology!From the day iPS first made its headlines when it was first produced by Shinya Yamanaka at Kyoto University in Japan, Stem Cell scientists all over the world are re- doing their experiments so far done using other sources like embryonic and adult Stem cells with the iPS cells exploring their potential to the fullest. A Stem Cell science news page without this magic word of iPS is difficult to imagine these days and Scientists have been successful in growing most of the adult Cell types from iPS cells.iPS cells was the key to solve the problems of Immune rejection and Immunosupression required when using other allogeneic Stem cell types which had baffled scientists previously. But the issues raised by scientists about the use of viruses and Oncogenes in producing iPS cells were made groundless when scientists in February 2008 published the discovery of a technique that could remove oncogenes after the induction of pluripotency and now it is possible to induce pluripotency using plasmid transfection, piggyback transposon system and piggyback transposon system combined with a non viral vector system. The word of the day is pIPS which are protein-induced Pluripotent stem cells which are iPS cells that were generated without any genetic alteration of the adult cell. This research by the group of Sheng Ding in La Jolla, California made public in April 2009 showed that the generation of poly-arginine anchors was sufficient to induce

  14. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  15. Immobilization chemistries.

    Science.gov (United States)

    Todt, Sascha; Blohm, Dietmar H

    2009-01-01

    Among the parameters which influence the success of a microarray experiment, the attachment of the nucleic acid captures to the support surface plays a decisive role.This article attempts to review the main concepts and ideas of the multiple variants which exist in terms of the immobilization chemistries used in nucleic acid microarray technology. Starting from the attachment of unmodified nucleic acids to modified glass slides by adsorption, further strategies for the coupling of nucleic acid capture molecules to a variety of support materials are surveyed with a focus on the reactive groups involved in the respective process.After a brief introduction, an overview is given about microarray substrates with special emphasis on the approaches used for the activation of these - usually chemically inert - materials. In the next sections strategies for the "undefined" and "defined" immobilization of captures on the substrates are described. While the latter approach tries to accomplish the coupling via a defined reactive moiety of the molecule to be immobilized, the former mentioned techniques involve multiply occurring reactive groups in the capture.The article finishes with an example for microarray manufacture, the production of aminopropyltriethoxysilane (APTES) functionalized glass substrates to which PDITC homobifunctional linker molecules are coupled; on their part providing reactive functional groups for the covalent immobilization of pre-synthesized, amino-modified oligonucleotides.This survey does not seek to be comprehensive rather it tries to present and provide key examples for the basic techniques, and to enable orientation if more detailed studies are needed. This review should not be considered as a guide to how to use the different chemistries described, but instead as a presentation of various principles and approaches applied in the still evolving field of nucleic acid microarray technology.

  16. Mathematical methods for physical and analytical chemistry

    CERN Document Server

    Goodson, David Z

    2011-01-01

    Mathematical Methods for Physical and Analytical Chemistry presents mathematical and statistical methods to students of chemistry at the intermediate, post-calculus level. The content includes a review of general calculus; a review of numerical techniques often omitted from calculus courses, such as cubic splines and Newton's method; a detailed treatment of statistical methods for experimental data analysis; complex numbers; extrapolation; linear algebra; and differential equations. With numerous example problems and helpful anecdotes, this text gives chemistry students the mathematical

  17. Simulation of a wide area survey for NEOs with Pan-STARRS PS1 & PS2 Telescopes

    Science.gov (United States)

    Chambers, Kenneth C.; Lilly (Schunova), Eva; Dukes, Martin Todd; Wainscoat, Richard J.

    2017-10-01

    We have performed a new survey simulation for a wide area survey with PS1 & PS2 as part of our quest to optimize the discovery rate of Near Earth Objects with the full Pan-STARRS system. The survey is intended to be as unbiased and as complete as possible given the available sky visibility and the anticipated performance of the PS1 and PS2 telescopes working together. The simulation includes a complete model of both telescopes, camera and slew overhead, sky visibility, moon phase, galactic plane exclusion, and weather. The performance of the resulting survey strategy is then evaluated using the method of Lilly et. al. 2017. This uses the Greenstreet et al. 2012 model with 50 million NEOs with absolute magnitudes 13 < H < 29 and the Moving Object Processing System (MOPS, Denneau et al. 2013) for linkages. The results are compared with other possible strategies.

  18. Profiling the microRNA Expression in Human iPS and iPS-derived Retinal Pigment Epithelium.

    Science.gov (United States)

    Wang, Heuy-Ching; Greene, Whitney A; Kaini, Ramesh R; Shen-Gunther, Jane; Chen, Hung-I H; Cai, Hong; Wang, Yufeng

    2014-01-01

    The purpose of this study is to characterize the microRNA (miRNA) expression profiles of induced pluripotent stem (iPS) cells and retinal pigment epithelium (RPE) derived from induced pluripotent stem cells (iPS-RPE). MiRNAs have been demonstrated to play critical roles in both maintaining pluripotency and facilitating differentiation. Gene expression networks accountable for maintenance and induction of pluripotency are linked and share components with those networks implicated in oncogenesis. Therefore, we hypothesize that miRNA expression profiling will distinguish iPS cells from their iPS-RPE progeny. To identify and analyze differentially expressed miRNAs, RPE was derived from iPS using a spontaneous differentiation method. MiRNA microarray analysis identified 155 probes that were statistically differentially expressed between iPS and iPS-RPE cells. Up-regulated miRNAs including miR-181c and miR-129-5p may play a role in promoting differentiation, while down-regulated miRNAs such as miR-367, miR-18b, and miR-20b are implicated in cell proliferation. Subsequent miRNA-target and network analysis revealed that these miRNAs are involved in cellular development, cell cycle progression, cell death, and survival. A systematic interrogation of temporal and spatial expression of iPS-RPE miRNAs and their associated target mRNAs will provide new insights into the molecular mechanisms of carcinogenesis, eye differentiation and development.

  19. General theory for multiple input-output perturbations in complex molecular systems. 1. Linear QSPR electronegativity models in physical, organic, and medicinal chemistry.

    Science.gov (United States)

    González-Díaz, Humberto; Arrasate, Sonia; Gómez-SanJuan, Asier; Sotomayor, Nuria; Lete, Esther; Besada-Porto, Lina; Ruso, Juan M

    2013-01-01

    In general perturbation methods starts with a known exact solution of a problem and add "small" variation terms in order to approach to a solution for a related problem without known exact solution. Perturbation theory has been widely used in almost all areas of science. Bhor's quantum model, Heisenberg's matrix mechanincs, Feyman diagrams, and Poincare's chaos model or "butterfly effect" in complex systems are examples of perturbation theories. On the other hand, the study of Quantitative Structure-Property Relationships (QSPR) in molecular complex systems is an ideal area for the application of perturbation theory. There are several problems with exact experimental solutions (new chemical reactions, physicochemical properties, drug activity and distribution, metabolic networks, etc.) in public databases like CHEMBL. However, in all these cases, we have an even larger list of related problems without known solutions. We need to know the change in all these properties after a perturbation of initial boundary conditions. It means, when we test large sets of similar, but different, compounds and/or chemical reactions under the slightly different conditions (temperature, time, solvents, enzymes, assays, protein targets, tissues, partition systems, organisms, etc.). However, to the best of our knowledge, there is no QSPR general-purpose perturbation theory to solve this problem. In this work, firstly we review general aspects and applications of both perturbation theory and QSPR models. Secondly, we formulate a general-purpose perturbation theory for multiple-boundary QSPR problems. Last, we develop three new QSPR-Perturbation theory models. The first model classify correctly >100,000 pairs of intra-molecular carbolithiations with 75-95% of Accuracy (Ac), Sensitivity (Sn), and Specificity (Sp). The model predicts probabilities of variations in the yield and enantiomeric excess of reactions due to at least one perturbation in boundary conditions (solvent, temperature

  20. Public perception of chemistry

    OpenAIRE

    Stražar, Alenka

    2015-01-01

    The thesis deals with the perception of chemistry among the public, which reflects the stereotypes that people have about chemistry. It presents the existing classification of stereotypes about chemistry and their upgrade. An analysis of movies that reflect the existing perception of chemistry in the public is written. Literature on selected aspects of the application of chemistry in movies is collected and analyzed. A qualification of perception of chemistry in the movies is presented based ...

  1. USSR Report Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    Contents: Adsorption, Chemistry,Alkaloids, Analytical Chemistry, Catalysis,Chemical Industry,,Coal Gasification, Combustion, Electrochemistry,Explosives and Explosions, Fertilizers, Free Radicals, Inorganic...

  2. Science Update: Inorganic Chemistry.

    Science.gov (United States)

    Rawls, Rebecca

    1981-01-01

    Describes areas of inorganic chemistry which have changed dramatically in the past year or two, including photochemistry, electrochemistry, organometallic complexes, inorganic reaction theory, and solid state chemistry. (DS)

  3. Principles of quantum chemistry

    CERN Document Server

    George, David V

    2013-01-01

    Principles of Quantum Chemistry focuses on the application of quantum mechanics in physical models and experiments of chemical systems.This book describes chemical bonding and its two specific problems - bonding in complexes and in conjugated organic molecules. The very basic theory of spectroscopy is also considered. Other topics include the early development of quantum theory; particle-in-a-box; general formulation of the theory of quantum mechanics; and treatment of angular momentum in quantum mechanics. The examples of solutions of Schroedinger equations; approximation methods in quantum c

  4. Impact of Amazonian deforestation on atmospheric chemistry

    NARCIS (Netherlands)

    Ganzeveld, L.N.; Lelieveld, J.

    2004-01-01

    A single-column chemistry and climate model has been used to study the impact of deforestation in the Amazon Basin on atmospheric chemistry. Over deforested areas, daytime ozone deposition generally decreases strongly except when surface wetness decreases through reduced precipitation, whereas

  5. A Teacher's View of Project Advance Chemistry.

    Science.gov (United States)

    Snow, Albert J.

    1984-01-01

    Project Advance is a high school chemistry program equivalent to chemistry taught on the Syracuse University campus. A survey reveals that teachers in general have positive attitudes and good impressions of the course. Positive attitudes and high regard for the experience were also noted by students completing the course. (JN)

  6. Implementation of a high resolution (< 11 ps RMS) Time-to-Digital Converter in a Field Programmable Gate Array

    Energy Technology Data Exchange (ETDEWEB)

    Ugur, Cahit [Helmholtz-Institut Mainz, Johannes Gutenberg-Universitaet Mainz (Germany); Bayer, Eugen [Department for Digital Electronics, University Kassel (Germany); Kurz, Nikolaus; Traxler, Michael [GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Michel, Jan [Institute for Nuclear Physics, Goethe University Frankfurt, Frankfurt am Main (Germany)

    2012-07-01

    A high resolution time-to-digital converter (TDC) was implemented in a general purpose field-programmable gate array (FPGA), a re-programmable digital chip. RMS and the time resolution of different channels are calculated for one clock cycle (5 ns) interval and a minimum of 10.3 ps RMS on two channels is achieved, which yields to a time resolution of 7.3 ps (10.3 ps/{radical}(2)) on a single channel. The TDC can be used in time-of-flight, time-over-threshold, drift time measurement applications as well as many other measurements with specific Front-End Electronics (FEE), e.g. charge measurements with charge-to-width (Q2W) FEE. The re-programmable flexibility of FPGAs also allows to have application specific features, e.g. trigger window, zero dead time etc.

  7. Characterization of crosslinked polystyrene(PS) beads in SBR matrix

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Yoon-Jong; Choe, Soonja [Inha Univ. (Korea, Republic of)

    1995-12-01

    Monodisperse sized crosslinked polystyrene(PS) beads were prepared by a reaction of semibatch emulsion polymerization with styrene monomer, divinylbenzene(DVB) crosslinking agent and potassium persulfate(K{sub 2}S{sub 2}O{sub 9}) initiator in the absence of emulsifier. The glass transition temperature(T{sub g}) and the mean diameter of the beads were increased from 100{degrees}C to 135{degrees}C and from 402 nm to 532 nm, respectively, for an incorporation of 2 to 10 mol% DVB. Crosslinking density was also linearly increased with DVB content. SEM microphotographs of SBR composite filled with various contents of PS beads revealed that PS beads are relatively well dispersed without changing the spherical shape of the beads in all range of compositions. In stress-strain analysis, elongation at break and tensile strength of SBR composite were increased with the bead content. Applicability of the PS beads as a filler in SBR matrix is tested by plotting Mooney-Rivlin or Guth-Smallwood equations. However, mechanical properties of the composite with the beads were not so excellent as those of the composite with carbon black. Crosslinked PS beads are still tentative as a white color reinforcing filler on SBR matrix.

  8. The PS complex produces the nominal LHC beam

    CERN Document Server

    Benedikt, Michael; Borburgh, J; Cappi, R; Chanel, M; Chohan, V; Cyvoct, G; Garoby, R; Grier, D G; Gruber, J; Hancock, S; Hill, C E; Jensen, E; Krusche, A; Lindroos, M; Métral, Elias; Métral, G; Metzmacher, K D; Olsfors, J; Pedersen, F; Raich, U; Riunaud, J P; Royer, J P; Sassowsky, M; Schindl, Karlheinz; Schönauer, Horst Otto; Thivent, M; Ullrich, H M; Völker, F V; Vretenar, Maurizio; Barnes, M; Blackmore, E W; Cifarelli, F; Clark, G; Jones, F; Koscielniak, Shane Rupert; Mammarella, F; Mitra, A; Poirier, R; Reiniger, K W; Ries, T C

    2000-01-01

    The LHC [1] will be supplied, via the SPS, with protons from the pre-injector chain comprising Linac2, PS Booster (PSB) and PS. These accelerators have under-gone a major upgrading programme [2] during the last five years so as to meet the stringent requirements of the LHC. These imply that many high-intensity bunches of small emittance and tight spacing (25 ns) be available at the PS extraction energy (25 GeV). The upgrading project involved an increase of Linac2 current, new RF systems in the PSB and the PS, raising the PSB energy from 1 to 1.4 GeV, two-batch filling of the PS and the installation of high-resolution beam profile measurement devices. With the project entering its final phase and most of the newly installed hardware now being operational, the emphasis switches to producing the nominal LHC beam and tackling the associated beam physics problems. While a beam with transverse characteristics better than nominal has been obtained, the longitudinal density still needs to be increased. An alternativ...

  9. A short textbook of colloid chemistry

    CERN Document Server

    Jirgensons, B

    1962-01-01

    A Short Textbook of Colloid Chemistry, Second Revised Edition details the factual aspect of colloid chemistry that includes the basic facts, established empirical and mathematical relationships, and practical applications. The chapters of the title are organized into two parts. In the first part, the text discusses the general concepts of colloid chemistry, such as the history and scope, basic terms, and basic methods in experiment with colloids. Part Two covers the technical aspect of colloid chemistry, such as the optical properties, electrical properties, and viscosity. The book will be of

  10. Chemistry Perfumes Your Daily Life

    Science.gov (United States)

    Fortineau, Anne-Dominique

    2004-01-01

    A synopsis on the history of perfumery is presented, along with the various processes accessible for obtaining natural perfume constituents, and creation of synthetic chemicals. The important contribution of organic chemists in the invention of perfumes, aspects of fragrance chemistry, and general information on the perfume industry are…

  11. Educational benefits of green chemistry

    Science.gov (United States)

    Desmond, Serenity; Ray, Christian; Andino Martínez, José G.

    2017-08-01

    In this article, we present our current state of affairs in the "greening" of general chemistry laboratories, at the University of Illinois at Urbana-Champaign. We recognize the need to quantify our environmental mark and what we plan to do to continue to strive to make our work more sustainable and educational.

  12. Final Results on the CERN PS Electrostatic Septa Consolidation Program

    CERN Document Server

    Borburgh, Jan; Bobbio, Piero; Carlier, Etienne; Hourican, Michael; Masson, Thierry; Müller, Tania; Prost, Antoine; Crescenti, Massimo

    2003-01-01

    The CERN PS electrostatic septum consolidation program is coming to completion after almost 4 years of development. The program was started to fulfil the increased requirements on vacuum performance and the need to reduce the time necessary for maintenance interventions. The new design of septum 31, used for the so-called 'continuous transfer' 5-turn extraction, and the related construction issues will be presented together with the operational experience gained during the PS 2002 run. In addition, the experience of two years of operation with the new generation septum 23, used for a resonant slow extraction, will be briefly discussed. The continued development undertaken since its installation in the PS ring in 2001 will also be described.

  13. A&T Sector Note on the PS transverse feedback

    CERN Document Server

    Coly, Marcel; Blas, Alfred; Sterbini, Guido; CERN. Geneva. ATS Department

    2017-01-01

    In a particle accelerator, several contributions can degrade the beam quality and particularly the beam transverse emittance. In this document we will describe a system used in the CERN Proton Synchrotron (PS) to cope with the injection steering errors and the transverse instabilities: the PS transverse feedback (PS TFB). As time progresses, this system is also being used for other purpose, to increase in a controlled way the beam transverse emittance and to excite the beam for the Multi-Turn-Extraction (MTE). In 2016, it has been successfully used on some operational beams to damp injection oscillations. This allowed to test the reliability of the system for its operational deployment. A piquet service is available in case of problem.

  14. SAFETY: STRICTER CONTROLS IN CONTROLLED AREAS IN THE PS

    CERN Document Server

    G. Daems

    2001-01-01

    The PS accelerators will soon stop for several months. Work will take place in controlled areas in the PS and will involve many people who are not always aware of the risks associated with the work sites. To guarentee the safety of these workers, the following two measures will be applied: everyone working in a controlled zone - Linacs, PSB, and PS machines tunnels, and transfer lines - must wear, visibly, his CERN access card and his film badge. the CERN access card and the film badge will only be issued after following a basic safety course. Regular checks will be carried out during the shutdown. Anyone without these two items on their person will be obliged to leave the area immediately.

  15. Electrophysical properties of PMN-PT-PS-PFN:Li ceramics

    Directory of Open Access Journals (Sweden)

    R. Skulski

    2013-01-01

    Full Text Available We present the technology of obtaining and the electrophysical properties of a multicomponent material 0.61PMN-0.20PT-0.09PS-0.1PFN:Li (PMN-PT-PS-PFN:Li. The addition of PFN into PMN-PT decreases the temperature of final sintering which is very important during technological process (addition of Li decreases electric conductivity of PFN. Addition of PS i.e., PbSnO3 (which is unstable in ceramic form permits to shift the temperature of the maximum of dielectric permittivity. One-step method of obtaining ceramic samples from oxides and carbonates has been used. XRD, microstructure, scanning calorimetry measurements and the main dielectric, ferroelectric and electromechanical properties have been investigated for the obtained samples.

  16. Chemistry in Our Life

    Indian Academy of Sciences (India)

    IAS Admin

    toothpaste, soaps and cosmetics, (7) plastics and polymers, (8) chemistry in health and disease, (9) chemistry of building, (10) fire chemistry and (11) chemistry of electricity. To write on these topics at a popular level for lay persons, without bringing in chemical for- mulas, structures or equations, is extremely difficult.

  17. A Reply to ''Reinterpretation of Students' Ideas When Reasoning about Particle Model Illustrations. A Response to ''Using Animations in Identifying General Chemistry Students' Misconceptions and Evaluating Their Knowledge Transfer Relating to Particle Position in Physical Changes'' by Smith and Villarreal (2015)''

    Science.gov (United States)

    Smith, K. Christopher; Villarreal, Savannah

    2015-01-01

    In this reply to Elon Langbeheim's response to an article recently published in this journal, authors Smith and Villarreal identify several types of general chemistry students' misconceptions concerning the concept of particle position during physical change. They focus their response on one of the misconceptions identified as such: Given a solid…

  18. Effect of interfaces on the melting of PEO confined in triblock PS-b-PEO-b-PS copolymers.

    Science.gov (United States)

    Beaudoin, E; Phan, T N T; Robinet, M; Denoyel, R; Davidson, P; Bertin, D; Bouchet, R

    2013-08-27

    Block copolymers form nanostructures that have interesting physical properties because they combine, for a single compound, the complementary features brought by each block. However, in order to fully exploit these properties, the physical state of each kind of domain must be precisely controlled. In this work, triblock PS-b-PEO-b-PS copolymers consisting of a central poly(ethylene oxide) (PEO) block covalently bonded to polystyrene (PS) blocks were synthesized by Atom Transfer Radical Polymerization. Their morphology was investigated by X-ray scattering and TEM experiments whereas their thermodynamic behavior was characterized by DSC. A strong decrease of both the melting temperature and the degree of crystallinity of PEO, due to its confinement between the PS domains, was observed and analyzed with a modified Gibbs-Thomson equation, following the approaches used for fluids confined in porous media. The existence of an amorphous bound layer, a few nanometers thick, at the PEO/PS interface, that does not undergo any phase transition in the temperature range investigated, accounts for both the melting temperature depression and the decrease of crystallinity upon confinement. This interfacial layer may significantly affect the mechanical and transport properties of these block copolymers that find applications as solid polymer electrolytes in batteries for example. Moreover, the value obtained for the solid PEO/liquid PEO surface tension is lower than those previously published but is thermodynamically consistent with the surface tensions of polymers at the solid/vapor and liquid/vapor interfaces.

  19. Mechanism of H2S Oxidation by the Dissimilatory Perchlorate-Reducing Microorganism Azospira suillum PS

    Directory of Open Access Journals (Sweden)

    Misha G. Mehta-Kolte

    2017-02-01

    Full Text Available The genetic and biochemical basis of perchlorate-dependent H2S oxidation (PSOX was investigated in the dissimilatory perchlorate-reducing microorganism (DPRM Azospira suillum PS (PS. Previously, it was shown that all known DPRMs innately oxidize H2S, producing elemental sulfur (So. Although the process involving PSOX is thermodynamically favorable (ΔG°′ = −206 kJ ⋅ mol−1 H2S, the underlying biochemical and genetic mechanisms are currently unknown. Interestingly, H2S is preferentially utilized over physiological electron donors such as lactate or acetate although no growth benefit is obtained from the metabolism. Here, we determined that PSOX is due to a combination of enzymatic and abiotic interactions involving reactive intermediates of perchlorate respiration. Using various approaches, including barcode analysis by sequencing (Bar-seq, transcriptome sequencing (RNA-seq, and proteomics, along with targeted mutagenesis and biochemical characterization, we identified all facets of PSOX in PS. In support of our proposed model, deletion of identified upregulated PS genes traditionally known to be involved in sulfur redox cycling (e.g., Sox, sulfide:quinone reductase [SQR] showed no defect in PSOX activity. Proteomic analysis revealed differential abundances of a variety of stress response metal efflux pumps and divalent heavy-metal transporter proteins, suggesting a general toxicity response. Furthermore, in vitro biochemical studies demonstrated direct PSOX mediated by purified perchlorate reductase (PcrAB in the absence of other electron transfer proteins. The results of these studies support a model in which H2S oxidation is mediated by electron transport chain short-circuiting in the periplasmic space where the PcrAB directly oxidizes H2S to So. The biogenically formed reactive intermediates (ClO2− and O2 subsequently react with additional H2S, producing polysulfide and So as end products.

  20. Basidiomycete-specific PsCaMKL1 encoding a CaMK-like protein kinase is required for full virulence of Puccinia striiformis f. sp. tritici.

    Science.gov (United States)

    Jiao, Min; Yu, Dan; Tan, Chenglong; Guo, Jia; Lan, Dingyun; Han, Ershang; Qi, Tuo; Voegele, Ralf Thomas; Kang, Zhensheng; Guo, Jun

    2017-10-01

    Calcium/calmodulin-dependent kinases (CaMKs) are Ser/Thr protein kinases (PKs) that respond to changes in cytosolic free Ca(2+) and play diverse roles in eukaryotes. In fungi, CAMKs are generally classified into four families CAMK1, CAMKL, RAD53 and CAMK-Unique. Among these, CAMKL constitutes the largest family. In some fungal plant pathogens, members of the CaMKL family have been shown to be responsible for pathogenesis. However, little is known about their role(s) in rust fungi. In this study, we functionally characterized a novel PK gene, PsCaMKL1, from Puccinia striiformis f. sp. tritici (Pst). PsCaMKL1 belongs to a group of PKs that is evolutionarily specific to basidiomyceteous fungi. PsCaMKL1 shows little intra-species polymorphism between Pst isolates. PsCaMKL1 transcripts are highly elevated at early infection stages, whereas gene expression is downregulated in barely germinated urediospores under KN93 treatment. Overexpression of PsCaMKL1 in fission yeast increased resistance to environmental stresses. Knock down of PsCaMKL1 using host-induced gene silencing (HIGS) reduced the virulence of Pst accompanied by reactive oxygen species (ROS) accumulation and a hypersensitive response. These results suggest that PsCaMKL1 is a novel pathogenicity factor that exerts it virulence function by regulating ROS production in wheat. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. Inauguration of POPS: the new power system of the PS

    CERN Multimedia

    Maximilien Brice

    2010-01-01

    Pictures 03 and 04 : The team from the Electrical Power Converters Group (TE/EPC) is joined by the Director of Accelerators, the heads of the BE, TE and FI departments, CERN managers and Converteam representatives in a group portrait in front of three of the containers that house the capacitor banks of the PS's new power supply system, POPS. Pictures 01, 06 and 07 : Magid-Michel Saikaly, energy and infrastructure director at Converteam, receives a prize from Steve Myers, Director of Accelerators at CERN, for the development and fabrication of the new electrical power system for the PS, called POPS.

  2. The Septa for LEIR Extraction and PS Injection

    CERN Document Server

    Borburgh, J; Masson, T; Prost, A

    2006-01-01

    The Low Energy Ion Ring (LEIR) is part of the CERN LHC injector chain for ions. The LEIR extraction uses a pulsed magnetic septum, clamped around a metallic vacuum chamber. Apart from separating the ultra high vacuum in the LEIR ring from the less good vacuum in the transfer line to the PS this chamber also serves as magnetic screen and retains the septum conductor in place. The PS ion injection septum consists of a pulsed laminated magnet under vacuum, featuring a single-turn water cooled coil and a remote positioning system. The design, the construction and the commissioning of both septa are described.

  3. Training of chemistry teachers for sustainable development

    Science.gov (United States)

    Gilmanshina, S. I.; Sagitova, R. N.; Melnikov, G. F.; Fedotova, R. R.

    2017-09-01

    Proposed and piloted teacher training plan containing elements of the concept of sustainable development. teacher training plan includes the development of general and specialized courses in chemical disciplines, organization of activities, taking into account the principles of Green Chemistry.

  4. The OMERACT psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS): definitions of key pathologies, suggested MRI sequences, and preliminary scoring system for PsA Hands

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; McQueen, Fiona; Wiell, Charlotte

    2009-01-01

    This article describes a preliminary OMERACT psoriatic arthritis magnetic resonance image scoring system (PsAMRIS) for evaluation of inflammatory and destructive changes in PsA hands, which was developed by the international OMERACT MRI in inflammatory arthritis group. MRI definitions of important...... pathologies in peripheral PsA and suggestions concerning appropriate MRI sequences for use in PsA hands are also provided....

  5. Green chemistry: A tool in Pharmaceutical Chemistry

    OpenAIRE

    Smita Talaviya; Falguni Majumdar

    2012-01-01

    Green chemistry expresses an area of research developing from scientific discoveries about pollution awareness and it utilizes a set of principles that reduces or eliminates the use or generation of hazardous substances in all steps of particular synthesis or process. Chemists and medicinal scientists can greatly reduce the risk to human health and the environment by following all the valuable principles of green chemistry. The most simple and direct way to apply green chemistry in pharmaceut...

  6. Optimization of protease production by an actinomycete Strain, PS ...

    African Journals Online (AJOL)

    Actinomycetes were isolated from the sediment samples of an estuarine shrimp pond located along the south east coast of India. During the investigation, a total of 28 strains of actinomycetes were isolated and examined for their protease activity. Among them, one strain PS-18A which was tentatively identified as ...

  7. Seismic receiver function interpretation: Ps splitting or anisotropic underplating?

    Science.gov (United States)

    Liu, Zhen; Park, Jeffrey

    2017-03-01

    Crustal anisotropy is crucial to understanding the evolutionary history of Earth's lithosphere. Shear wave splitting of Moho P-to-S converted phases in receiver functions (RFs) have been often used to study crustal anisotropy. Harmonic variation of Moho Ps phases in delay times are used to infer splitting parameters of averaged anisotropy in the crust. However, crustal anisotropy may distribute at various levels within the crust due to complex deformational processes. Layered anisotropy requires careful investigation of the distribution of anisotropy before interpreting Moho Ps splitting. In this study, we show results from stations ARU in Russia, KIP in the Hawaiian Islands and LSA in Tibetan Plateau, where layered anisotropy is constrained well by intracrust Ps conversions at high frequencies using a harmonic-decomposition technique. Anisotropic velocity models are inferred by forward-modeling decomposed RF waveforms. We suggest that the harmonic variation of Moho Ps phases should always be investigated to check for anisotropic layering using RFs with frequency content above 1 Hz, rather than simply reporting averaged anisotropy of the whole crust.

  8. Optimization of protease production by an actinomycete Strain, PS ...

    African Journals Online (AJOL)

    STORAGESEVER

    Isolation Agar Medium in duplicate Petri plates. To minimize ... on the Petri plates were counted from 5th day onwards, up to 28th .... After the dialysis, the volume was measured and analyzed for proteins and stored in deep freezer. Taxonomic investigation. The genus level identification was made for the strain PS-18A using ...

  9. Framing Retention for Institutional Improvement: A 4 Ps Framework

    Science.gov (United States)

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps framework for student retention strategy is a construct for reframing the retention discussion in a way that enables institutional improvement by challenging some conventional wisdom and prevailing perspectives that have characterized retention strategy for years. It opens new possibilities for action and improvement by suggesting that…

  10. Multipole stack for the 4 rings of the PS Booster

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The PS Booster (originally 800 MeV, now 1.4 GeV) saw first beam in 1972, routine operation began in 1973. The strive for ever higher intensities required the addition of multipoles. Manufacture of 8 stacks of multipoles was launched in 1974, for installation in 1976. For details, see 7511120X.

  11. The Swelling Behaviour of Polystyrene (PS)/ Polyvinylacetate (Pvac ...

    African Journals Online (AJOL)

    The effect of the variation of the type of solvent responsible for the differences in the swelling kinetics of Polystyrene (PS) and Polyvinyl acetate (PVAc) blends was studied. The results showed that the nature of solvent control or affects the degree of swelling. Also, 1-V characteristics at temperature range of 323-363K shows ...

  12. Boiling treatment of ABS and PS plastics for flotation separation.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Wu, Bao-xin; Liu, Qun

    2014-07-01

    A new physical method, namely boiling treatment, was developed to aid flotation separation of acrylonitrile-butadiene-styrene (ABS) and polystyrene (PS) plastics. Boiling treatment was shown to be effective in producing a hydrophilic surface on ABS plastic. Fourier Transform Infrared analysis was conducted to investigate the mechanism of boiling treatment of ABS. Surface rearrangement of polymer may be responsible for surface change of boiling treated ABS, and the selective influence of boiling treatment on the floatability of boiling treated plastics may be attributed to the difference in the molecular mobility of polymer chains. The effects of flotation time, frother concentration and particle size on flotation behavior of simple plastic were investigated. Based on flotation behavior of simple plastic, flotation separation of boiling treatment ABS and PS with different particle sizes was achieved efficiently. The purity of ABS and PS was up to 99.78% and 95.80%, respectively; the recovery of ABS and PS was up to 95.81% and 99.82%, respectively. Boiling treatment promotes the industrial application of plastics flotation and facilitates plastic recycling. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Part 6: The Literature of Inorganic Chemistry, Revised.

    Science.gov (United States)

    Douville, Judith A.

    2002-01-01

    Presents a list of resources on inorganic chemistry that includes general surveys, nomenclature, dictionaries, handbooks, compilations, and treatises. Selected for use by academic and student chemists. (DDR)

  14. Mars aqueous chemistry experiment

    Science.gov (United States)

    Clark, Benton C.; Mason, Larry W.

    1993-01-01

    The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

  15. psRNATarget: a plant small RNA target analysis server.

    Science.gov (United States)

    Dai, Xinbin; Zhao, Patrick Xuechun

    2011-07-01

    Plant endogenous non-coding short small RNAs (20-24 nt), including microRNAs (miRNAs) and a subset of small interfering RNAs (ta-siRNAs), play important role in gene expression regulatory networks (GRNs). For example, many transcription factors and development-related genes have been reported as targets of these regulatory small RNAs. Although a number of miRNA target prediction algorithms and programs have been developed, most of them were designed for animal miRNAs which are significantly different from plant miRNAs in the target recognition process. These differences demand the development of separate plant miRNA (and ta-siRNA) target analysis tool(s). We present psRNATarget, a plant small RNA target analysis server, which features two important analysis functions: (i) reverse complementary matching between small RNA and target transcript using a proven scoring schema, and (ii) target-site accessibility evaluation by calculating unpaired energy (UPE) required to 'open' secondary structure around small RNA's target site on mRNA. The psRNATarget incorporates recent discoveries in plant miRNA target recognition, e.g. it distinguishes translational and post-transcriptional inhibition, and it reports the number of small RNA/target site pairs that may affect small RNA binding activity to target transcript. The psRNATarget server is designed for high-throughput analysis of next-generation data with an efficient distributed computing back-end pipeline that runs on a Linux cluster. The server front-end integrates three simplified user-friendly interfaces to accept user-submitted or preloaded small RNAs and transcript sequences; and outputs a comprehensive list of small RNA/target pairs along with the online tools for batch downloading, key word searching and results sorting. The psRNATarget server is freely available at http://plantgrn.noble.org/psRNATarget/.

  16. Popular Science Articles for Chemistry Teaching

    Directory of Open Access Journals (Sweden)

    Ketevan Kupatadze

    2017-07-01

    Full Text Available The presented paper reviews popular science articles (these articles are published in online magazine “The Teacher” as one of the methods of chemistry teaching. It describes which didactic principles they are in line with and how this type of articles can be used in order to kindle the interest of pupils, students and generally, the readers of other specialties, in chemistry.  The articles review the main topics of inorganic/organic chemistry, biochemistry and ecological chemistry in a simple and entertaining manner. A part of the articles is about "household" chemistry. Chemical topics are related to poetry, literature, history of chemistry or simply, to fun news. The paper delineates the structure of popular science articles and the features of engaging students. It also reviews the teachers' and students' interview results about the usage of popular science articles in chemistry teaching process. The aforementioned pedagogical study revealed that the popular science articles contain useful information not only for the students of other specialties, but also for future biologists and ecologists (having chemistry as a mandatory subject at their universities. The articles are effectively used by teachers on chemistry lessons to kindle students' interest in this subject. DOI: http://dx.doi.org/10.17807/orbital.v9i3.960 

  17. Constitutional dynamic chemistry: bridge from supramolecular chemistry to adaptive chemistry.

    Science.gov (United States)

    Lehn, Jean-Marie

    2012-01-01

    Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels.CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation.The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter.

  18. The role of a conserved membrane proximal cysteine in altering αPS2CβPS integrin diffusion

    Science.gov (United States)

    Syed, Aleem; Arora, Neha; Bunch, Thomas A.; Smith, Emily A.

    2016-12-01

    Cysteine residues (Cys) in the membrane proximal region are common post-translational modification (PTM) sites in transmembrane proteins. Herein, the effects of a highly conserved membrane proximal α-subunit Cys1368 on the diffusion properties of αPS2CβPS integrins are reported. Sequence alignment shows that this cysteine is palmitoylated in human α3 and α6 integrin subunits. Replacing Cys1368 in wild-type integrins with valine (Val1368) putatively blocks a PTM site and alters integrins’ ligand binding and diffusion characteristics. Both fluorescence recovery after photobleaching (FRAP) and single particle tracking (SPT) diffusion measurements show Val1368 integrins are more mobile compared to wild-type integrins. Approximately 33% and 8% more Val1368 integrins are mobile as measured by FRAP and SPT, respectively. The mobile Val1368 integrins also exhibit less time-dependent diffusion, as measured by FRAP. Tandem mass spectrometry data suggest that Cys1368 contains a redox or palmitoylation PTM in αPS2CβPS integrins. This membrane proximal Cys may play an important role in the diffusion of other alpha subunits that contain this conserved residue.

  19. [Retinal Cell Therapy Using iPS Cells].

    Science.gov (United States)

    Takahashi, Masayo

    2016-03-01

    Progress in basic research, starting with the work on neural stem cells in the middle 1990's to embryonic stem (ES) cells and induced pluripotent stem (iPS) cells at present, will lead the cell therapy (regenerative medicine) of various organs, including the central nervous system to a big medical field in the future. The author's group transplanted iPS cell-derived retinal pigment epithelial (RPE) cell sheets to the eye of a patient with exudative age-related macular degeneration (AMD) in 2014 as a clinical research. Replacement of the RPE with the patient's own iPS cell-derived young healthy cell sheet will be one new radical treatment of AMD that is caused by cellular senescence of RPE cells. Since it was the first clinical study using iPS cell-derived cells, the primary endpoint was safety judged by the outcome one year after surgery. The safety of the cell sheet has been confirmed by repeated tumorigenisity tests using immunodeficient mice, as well as purity of the cells, karyotype and genetic analysis. It is, however, also necessary to prove the safety by clinical studies. Following this start, a good strategy considering cost and benefit is needed to make regenerative medicine a standard treatment in the future. Scientifically, the best choice is the autologous RPE cell sheet, but autologous cell are expensive and sheet transplantation involves a risky part of surgical procedure. We should consider human leukocyte antigen (HLA) matched allogeneic transplantation using the HLA 6 loci homozyous iPS cell stock that Prof. Yamanaka of Kyoto University is working on. As the required forms of donor cells will be different depending on types and stages of the target diseases, regenerative medicine will be accomplished in a totally different manner from the present small molecule drugs. Proof of concept (POC) of photoreceptor transplantation in mouse is close to being accomplished using iPS cell-derived photoreceptor cells. The shortest possible course for treatment

  20. A transmissão psíquica geracional

    Directory of Open Access Journals (Sweden)

    Vinícius Oliveira dos Santos

    Full Text Available O artigo seguinte refere-se a um estudo sobre como ocorre a transmissão psíquica entre as gerações e qual sua importância na constituição psíquica do sujeito. É também objetivo deste artigo explicar o que são as transmissões intergeracional e transgeracional. Para buscar respostas para essas questões, fez-se uma pesquisa bibliográfica sobre a transmissão psíquica, pelo viés psicanalítico, principalmente a partir da teoria lacaniana e com conceitos oriundos da linguística saussuriana. Será a partir de uma determinada ordem simbólica, constituída pela linguagem que precede o sujeito, nomeado por Lacan como o Outro, que a transmissão psíquica entre gerações ganhará o seu caráter unívoco, sempre se tendo em mente a importância fundamental do recalcamento e de seus efeitos, bem como do retorno do recalcado nas diferentes gerações. A transmissão psíquica é necessária e concomitante à constituição do sujeito, e ocorre através da linguagem, dos significantes que irão determinar uma ordem simbólica para o ser que nasce através dos diferentes discursos que perpassam as gerações nas figuras dos pais desse novo ser. Essa ordem simbólica continuará a se fazer presente nesse novo sujeito pelo restante de sua existência. Este artigo busca dar nova luz ao aspecto da transmissão psíquica transgeracional, diferenciando-se da recalque s abordagens psicanalíticas contemporâneas por ser uma leitura lacaniana. Serão usados dois exemplos: um de como a transmissão aparece na cultura, outro, na subjetividade do sujeito através da arte.

  1. Environmental chemistry: Volume A

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T.F.

    1999-08-01

    This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

  2. A dictionary of chemistry

    National Research Council Canada - National Science Library

    Daintith, John

    2008-01-01

    "Fully revised and updated, the sixth edition of this popular dictionary covers all aspects of chemistry from physical chemistry to biochemisty, and boasts broader coverage in forensics, metallurgy, and geology...

  3. Organometallic Chemistry of Molybdenum.

    Science.gov (United States)

    Lucas, C. Robert; Walsh, Kelly A.

    1987-01-01

    Suggests ways to avoid some of the problems students have learning the principles of organometallic chemistry. Provides a description of an experiment used in a third-year college chemistry laboratory on molybdenum. (TW)

  4. Advanced Chemistry Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...

  5. Green Chemistry and Education.

    Science.gov (United States)

    Hjeresen, Dennis L.; Schutt, David L.; Boese, Janet M.

    2000-01-01

    Many students today are profoundly interested in the sustainability of their world. Introduces Green Chemistry and its principles with teaching materials. Green Chemistry is the use of chemistry for pollution prevention and the design of chemical products and processes that are environmentally benign. (ASK)

  6. Compressed Sensing for Chemistry

    Science.gov (United States)

    Sanders, Jacob Nathan

    Many chemical applications, from spectroscopy to quantum chemistry, involve measuring or computing a large amount of data, and then compressing this data to retain the most chemically-relevant information. In contrast, compressed sensing is an emergent technique that makes it possible to measure or compute an amount of data that is roughly proportional to its information content. In particular, compressed sensing enables the recovery of a sparse quantity of information from significantly undersampled data by solving an ℓ 1-optimization problem. This thesis represents the application of compressed sensing to problems in chemistry. The first half of this thesis is about spectroscopy. Compressed sensing is used to accelerate the computation of vibrational and electronic spectra from real-time time-dependent density functional theory simulations. Using compressed sensing as a drop-in replacement for the discrete Fourier transform, well-resolved frequency spectra are obtained at one-fifth the typical simulation time and computational cost. The technique is generalized to multiple dimensions and applied to two-dimensional absorption spectroscopy using experimental data collected on atomic rubidium vapor. Finally, a related technique known as super-resolution is applied to open quantum systems to obtain realistic models of a protein environment, in the form of atomistic spectral densities, at lower computational cost. The second half of this thesis deals with matrices in quantum chemistry. It presents a new use of compressed sensing for more efficient matrix recovery whenever the calculation of individual matrix elements is the computational bottleneck. The technique is applied to the computation of the second-derivative Hessian matrices in electronic structure calculations to obtain the vibrational modes and frequencies of molecules. When applied to anthracene, this technique results in a threefold speed-up, with greater speed-ups possible for larger molecules. The

  7. PsVPS1, a dynamin-related protein, is involved in cyst germination and soybean infection of Phytophthora sojae.

    Directory of Open Access Journals (Sweden)

    Delong Li

    Full Text Available Plant pathogens secrete effector proteins to suppress plant immunity. However, the mechanism by which oomycete pathogens deliver effector proteins during plant infection remains unknown. In this report, we characterized a Phytophthora sojae vps1 gene. This gene encodes a homolog of the Saccharomyces cerevisiae vacuolar protein sorting gene vps1 that mediates budding of clathrin-coated vesicles from the late Golgi, which are diverted from the general secretory pathway to the vacuole. PsVPS1-silenced mutants were generated using polyethylene glycol-mediated protoplast stable transformation and were viable but had reduced extracellular protein activity. The PsVPS1-silenced mutants showed impaired hyphal growth, and the shapes of the vacuoles were highly fragmented. Silencing of PsVPS1 affected cyst germination as well as the polarized growth of germinated cysts. Silenced mutants showed impaired invasion of susceptible soybean plants regardless of wounding. These results suggest that PsVPS1 is involved in vacuole morphology and cyst development. Moreover, it is essential for the virulence of P. sojae and extracellular protein secretion.

  8. Transfer line from the PSB to the PS (recombination)

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    After sequential ejection of 5 bunches from each of the 4 rings of the Booster (originally 800 MeV, now 1.4 GeV), the 4 batches are brought to the same vertical level, so as to form a string of 20 bunches, filling the circumference of the PS. This vertical "recombination" is performed in the transfer line, using vertical bending magnets, septa and kickers. Here we see the section where the beam from ring 4 (the top one) is brought down to the level of ring 3, and the beam from ring 1 up to the level of ring 2. Further downstream (to the right, outside this picture), level 2 is brought up to level 3, identical to that of the PS. After this original recombination scheme, other ways of combining the 4 beams, vertically and/or longitudinally, were developed and used in operation.

  9. O Trabalho Psíquico da Intersubjetividade

    Directory of Open Access Journals (Sweden)

    Maria Inês Assumpção Fernandes

    2003-01-01

    Full Text Available O presente trabalho procura refletir sobre o trabalho psíquico da intersubjetividade nos grupos. Trata-se de pensá-lo na relação com a ruptura de investimentos durante o processo de Transformação x Criação, em primeiro lugar. A partir desse ponto, discutiremos a relação entre Transformação, Trabalho e Dispositivo. Neste caso pensamos nas possibilidades de intervenção, refletindo sobre a intervenção inpidual e a intervenção grupal. A questão da Transmissão Psíquica entre gerações será focalizada, fundamentalmente, no que se refere aos tempos lógicos do recalque.

  10. Images of Christ's Saving Work in Ps.-Epiphanius' Homilies

    Directory of Open Access Journals (Sweden)

    H. F. Stander

    1997-12-01

    Full Text Available Images of Christ's Saving Work in Ps.-Epiphanius' Homilies. One cannot really speak of a systematic theology on the subject of atone-ment in the patristic writers. Frances Young once said that 'it is in fact impossible to categorize neatly the thought of the major patristic writers on the subject of atonement'. She adds that one cannot do justice to the range of motifs and images that are found in describing the saving and atoning work of Christ if we merely dismember 'systematic theologies' to illustrate common soteriological themes. One can only appreciate patristic views of atonement if one begins by recognizing the multifaceted unity of imagery that pervades the literature. This then is the goal of this article: to discuss the rich images which Ps: -Epiphanius uses to describe the atoning work of Christ.

  11. Magnetoelectric MnPS3 as a candidate for ferrotoroidicity

    Science.gov (United States)

    Ressouche, E.; Loire, M.; Simonet, V.; Ballou, R.; Stunault, A.; Wildes, A.

    2010-09-01

    We have revisited the magnetic structure of manganese phosphorus trisulfide MnPS3 using neutron diffraction and polarimetry. MnPS3 undergoes a transition toward a collinear antiferromagnetic order at 78 K. The resulting magnetic point-group breaks both the time reversal and the space inversion thus allowing a linear magnetoelectric coupling. Neutron polarimetry was subsequently used to prove that this coupling provides a way to manipulate the antiferromagnetic domains simply by cooling the sample under crossed magnetic and electrical fields, in agreement with the nondiagonal form of the magnetoelectric tensor. In addition, this tensor has, in principle, an antisymmetric part that results in a toroidic moment and provides with a pure ferrotoroidic compound.

  12. PS Dreyer: Bakens op die pad van die wetenskap

    Directory of Open Access Journals (Sweden)

    A. J. Antonites

    1986-01-01

    Full Text Available PS Dreyer: Beacons on the path of science Professor PS Dreyer is an academic who has shown insight and vision into several problems of the human sciences since 1951. He has identified problems, but also contributed solutions to them. In this respect his philosophy on causality and freedom is of utmost importance. The same applies to his investigations into the relationship history-Christianity as well as the unity of sciences and how the concepts scientific, unscientic and nonscientific are related to one another. His contribution to the understanding of Greek philosophy should be of significance for time to come. Two milestones could be distinguished: Dreyer's particular solution to the problem of the criterion on truth, viz meaningfulness and his notion of the knowledge of values in ethics by valuation in contradistinction to knowledge through feeling, reason and will.

  13. Images of Christ's Saving Work in Ps.-Epiphanius' Homilies

    Directory of Open Access Journals (Sweden)

    H. F. Stander

    1997-01-01

    Full Text Available Images of Christ's Saving Work in Ps.-Epiphanius' Homilies. One cannot really speak of a systematic theology on the subject of atone-ment in the patristic writers. Frances Young once said that 'it is in fact impossible to categorize neatly the thought of the major patristic writers on the subject of atonement'. She adds that one cannot do justice to the range of motifs and images that are found in describing the saving and atoning work of Christ if we merely dismember 'systematic theologies' to illustrate common soteriological themes. One can only appreciate patristic views of atonement if one begins by recognizing the multifaceted unity of imagery that pervades the literature. This then is the goal of this article: to discuss the rich images which Ps: -Epiphanius uses to describe the atoning work of Christ.

  14. Longitudinal coupled-bunch instability studies in the PS

    CERN Document Server

    Damerau, H

    2017-01-01

    The main longitudinal limitation for LHC-type beams inthe PS are coupled-bunch instabilities. A dedicated proto-typefeedbacksystemusingaFinemetcavityasalongitudinalkicker has been installed. Extensive tests with beam havebeen performed to explore the intensity reach with this feed-back. The maximum intensity with nominal longitudinalemittance at PS extraction has been measured, as well as theemittance required to keep the beam longitudinally stableat the design intensity for the High-Luminosity LHC (HL-LHC). A higher-harmonic cavity is a complementary op-tion to extend the intensity reach beyond the capabilities ofthe coupled-bunch feedback. Preliminary machine develop-ment (MD) studies operating one20MHzor one40MHzRF system as a higher harmonic at the flat-top indicate thebeneficial effect on longitudinal beam stability

  15. American Association for Clinical Chemistry

    Science.gov (United States)

    ... Find the answer to your question IN CLINICAL CHEMISTRY Hs-cTnI as a Gatekeeper for Further Cardiac ... Online Harmonization.net Commission on Accreditation in Clinical Chemistry American Board of Clinical Chemistry Clinical Chemistry Trainee ...

  16. Functional characterization of calcineurin homologs PsCNA1/PsCNB1 in Puccinia striiformis f. sp. tritici using a host-induced RNAi system.

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    Full Text Available Calcineurin plays a key role in morphogenesis, pathogenesis and drug resistance in most fungi. However, the function of calcineurin genes in Puccinia striiformis f. sp. tritici (Pst is unclear. We identified and characterized the calcineurin genes PsCNA1 and PsCNB1 in Pst. Phylogenetic analyses indicate that PsCNA1 and PsCNB1 form a calcium/calmodulin regulated protein phosphatase belonging to the calcineurin heterodimers composed of subunits A and B. Quantitative RT-PCR analyses revealed that both PsCNA1 and PsCNB1 expression reached their maximum in the stage of haustorium formation, which is one day after inoculation. Using barely stripe mosaic virus (BSMV as a transient expression vector in wheat, the expression of PsCNA1 and PsCNB1 in Pst was suppressed, leading to slower extension of fungal hyphae and reduced production of urediospores. The immune-suppressive drugs cyclosporin A and FK506 markedly reduced the germination rates of urediospores, and when germination did occur, more than two germtubes were produced. These results suggest that the calcineurin signaling pathway participates in stripe rust morphogenetic differentiation, especially the formation of haustoria during the early stage of infection and during the production of urediospores. Therefore PsCNA1 and PsCNB1 can be considered important pathogenicity genes involved in the wheat-Pst interaction.

  17. Consolidation of the 45-Year Old PS Main Magnet System

    CERN Document Server

    Zickler, Thomas; Kalbreier, Wilhelm; Mess, Karl Hubert; Newborough, Antony

    2006-01-01

    After a major coil insulation breakdown on two of the 47-year-old CERN PS main magnets in 2003, an extensive magnet consolidation program has been launched. This article reviews the analysis of the magnet state be-fore the repair and the applied major improvements. An overview is given of the production of the new compo-nents, the actual refurbishment and the commissioning of the main magnet system after 18 months shutdown.

  18. Specification of the Beam Position Measurement in the PS Machine

    CERN Document Server

    Bravin, Enrico; Chanel, M; Ludwig, M; Métral, Elias; Métral, G; Potier, J P; Raich, U; Scrivens, R; Steerenberg, R; CERN. Geneva. AB Department

    2003-01-01

    This specification, drawn up by the instrumentation specification board 2, describes the requirements concerning orbit and trajectory measurements in the PS machine. The orbit measurement and the trajectory measurement are both indispensable in order to be able to guarantee the correct beam quality for beams like LHC, the future Grand Sasso beam, the nTOF beam and surely the combined operation of the nTOF beam and the East Area beam.

  19. Science spin: iPS cell research in the news.

    Science.gov (United States)

    Caulfield, T; Rachul, C

    2011-05-01

    Big scientific developments have always been spun to meet particular social agendas. We have seen it in the context of global warming, nuclear power, and genetically modified organisms. But few stories illustrate the phenomenon of spin as well as the reaction, and concomitant media coverage, that surrounded the November 2007 announcement regarding the reprogramming of skin cells to produce cells with qualities comparable to those of human embryonic stem cells (hESCs) known as induced pluripotent stem (iPS) cells.

  20. Physics at the AD/PS/SPS (1/4)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Lecture 1: The CERN injector complex and beams for non-LHC physics. The various machines and beam lines in the CERN injector complex are presented, from the linacs to the SPS. Special emphasis is given to the beam lines at the PS and SPS machines: AD, North and East Areas, nTOF and CNGS and HiRadMad as well as the ion beams. A short outlook is given to possible future upgrades and projects.

  1. Ps18.pdf | sep2002 | jess | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; jess; sep2002; Ps18.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Associates – 2017. Posted on 17 July 2017. Click here to see the list · 28th Mid Year Meeting. Posted on 26 May ...

  2. New Electron Cloud Detectors for the PS Main Magnets

    CERN Document Server

    Yin Vallgren, Ch; Gilardoni, S; Taborelli, M; Neupert, H; Ferreira Somoza, J

    2014-01-01

    Electron cloud (EC) has already been observed during normal operation of the PS, therefore it is necessary to study its in fluence on any beam instability for the future LHC Injector Upgrade (LIU). Two new electron cloud detectors have been discussed, developed and installed during the Long Shutdown (LS1) in one of the PS main magnets. The first measurement method is based on current measurement by using a shielded button-type pick-up. Due to the geometry and space limitation in the PS magnet, the button-type pick-up made of a 96%Al2O3 block coated with a thin layer of solvent-based Ag painting, placed 30 degrees to the bottom part of the vacuum chamber was installed in the horizontal direction where the only opening of the magnet coil is. The other newly developed measurement method is based on detection of photons emitted by the electrons from the electron cloud impinging on the vacuum chamber walls. The emitted photons are reected to a quartz window. A MCP-PMT (Micro-Channel Plate Photomultiplier Tube) wit...

  3. LS1 Report: PS Booster prepares for beam

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    With Linac2 already up and running, the countdown to beam in the LHC has begun! The next in line is the PS Booster, which will close up shop to engineers early next week. The injector will be handed over to the Operations Group who are tasked with getting it ready for active duty.   Taken as we approach the end of LS1 activities, this image shows where protons will soon be injected from Linac2 into the four PS Booster rings. Over the coming two months, the Operations Group will be putting the Booster's new elements through their paces. "Because of the wide range of upgrades and repairs carried out in the Booster, we have a very full schedule of tests planned for the machine," says Bettina Mikulec, PS Booster Engineer in Charge. "We will begin with cold checks; these are a wide range of tests carried out without beam, including system tests with power on/off and with varying settings, as well as verification of the controls system and timings." Amon...

  4. Annual Report of Institute of Nuclear Chemistry and Technology 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-10-01

    The report is the collection of short communications being the review of the scientific activity of Institute of Nuclear Chemistry and Technology - Warsaw in 1997. The papers are gathered in several branches as follows: radiation chemistry and physics; radiochemistry, stable isotopes, nuclear analytical methods, chemistry in general; radiobiology; nuclear technologies and methods. The annual report of INCT-1997 contains also the general information about INCT as well as the full list of scientific papers being published by the staff in 1997

  5. Teaching Green and Sustainable Chemistry: A Revised One-Semester Course Based on Inspirations and Challenges

    Science.gov (United States)

    Marteel-Parrish, Anne E.

    2014-01-01

    An elective course, "Toward the Greening of Our Minds": Green and Sustainable Chemistry, has been offered at Washington College since 2005. This new course without laboratory is designed for chemistry and biology majors and minors who have previously taken two semesters of general chemistry and organic chemistry. Due to the popularity of…

  6. The New Color of Chemistry: Green Chemistry

    Directory of Open Access Journals (Sweden)

    Zuhal GERÇEK

    2012-01-01

    Full Text Available Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provide a solution for this requirement, green chemistry rules and under standings should be primarily taken in the university curriculum and at all educational levels.

  7. Surface chemistry essentials

    CERN Document Server

    Birdi, K S

    2013-01-01

    Surface chemistry plays an important role in everyday life, as the basis for many phenomena as well as technological applications. Common examples range from soap bubbles, foam, and raindrops to cosmetics, paint, adhesives, and pharmaceuticals. Additional areas that rely on surface chemistry include modern nanotechnology, medical diagnostics, and drug delivery. There is extensive literature on this subject, but most chemistry books only devote one or two chapters to it. Surface Chemistry Essentials fills a need for a reference that brings together the fundamental aspects of surface chemistry w

  8. Kultuur isiksuse psühholoogiat ei mõjuta / Tiit Kändler

    Index Scriptorium Estoniae

    Kändler, Tiit, 1948-

    2010-01-01

    Psühholoogia uuemate andmete kohaselt ei sõltu indiviidi seadumus kultuurist, soost, vanusest, haridusest. Eesti psühholoogide Jüri Alliku ja Ann Realo osalusel ajakirjas "Journal Personality and Social Psychology" ilmunud artiklist

  9. Kultuur isiksuse psühholoogiat ei mõjuta / Tiit Kändler

    Index Scriptorium Estoniae

    Kändler, Tiit, 1948-

    2005-01-01

    Psühholoogia uuemate andmete kohaselt ei sõltu indiviidi seadumus kultuurist, soost, vanusest, haridusest. Eesti psühholoogide Jüri Alliku ja Anu Realo osalusel ajakirjas "Journal Personality and Social Psychology" ilmunud artiklist

  10. Comparative, validity and responsiveness of the HOOS-PS and KOOS-PS to the WOMAC physical function subscale in total joint replacement for osteoarthritis

    DEFF Research Database (Denmark)

    Davis, A M; Perruccio, A V; Canizares, M

    2009-01-01

    OBJECTIVE: To evaluate the internal consistency of the Hip disability and Osteoarthritis Outcome Score-Physical Function Short-form (HOOS-PS) and the Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form (KOOS-PS) in total hip replacement (THR) and total knee (TKR) replacement....... Construct validity and responsiveness were compared to the Western Ontario McMaster Universities' Osteoarthritis Index (WOMAC) Likert 3.0 physical function (PF) subscale and the PF excluding the items in the short measures (PF-exclusions). METHODS: Participants completed the full HOOS or KOOS, measures...... of fatigue, anxiety, depression and the Chronic Pain Grade (CPG) pre-surgery and the HOOS or KOOS 6 months post-surgery. Internal consistency for the HOOS-PS and KOOS-PS was calculated using Cronbach's alpha. For construct validity, it was hypothesized that correlations between the HOOS-PS or KOOS-PS and PF...

  11. Analüütilised voolud psühholoogias ja nende rakendamine pedagoogikas / Aleksander Elango

    Index Scriptorium Estoniae

    Elango, Aleksander, 1902-2004

    2001-01-01

    Analüütise psühholoogia kolm koolkonda - S.Freudì koolkond e. päris-psühhoanalüüs, A.Adlerì koolkond e. individuaalpsühholoogia ja C.G.Jungì psühhoanalüüsi ja individuaalpsühholoogia sünteesi luua püüdev koolkond. Analüütise psühholoogia koolkondade ja pedagoogika suhetest

  12. The New Color of Chemistry: Green Chemistry

    OpenAIRE

    Zuhal GERÇEK

    2012-01-01

    Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provid...

  13. File list: His.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.05.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX317576,S...077,SRX317607 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.05.AllAg.iPS_cells.bed ...

  14. File list: His.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.50.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127376,SRX146530,SRX146522,SRX146547,SRX333561,SRX035985,SRX1090869 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.50.AllAg.iPS_cells.bed ...

  15. File list: ALL.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.50.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX088...16,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.50.AllAg.iPS_cells.bed ...

  16. File list: His.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.10.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110016,S...315,SRX381309 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.10.AllAg.iPS_cells.bed ...

  17. File list: ALL.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.20.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX088...27,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.20.AllAg.iPS_cells.bed ...

  18. File list: His.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.50.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110015,S...079,SRX317585 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.50.AllAg.iPS_cells.bed ...

  19. File list: Pol.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.20.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.20.AllAg.iPS_cells.bed ...

  20. File list: ALL.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.05.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX753...00,SRX189399,SRX317607 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.05.AllAg.iPS_cells.bed ...

  1. File list: Pol.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.10.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.10.AllAg.iPS_cells.bed ...

  2. File list: ALL.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.05.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9774...30,SRX146524,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.05.AllAg.iPS_cells.bed ...

  3. File list: Oth.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.50.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX97...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.50.AllAg.iPS_cells.bed ...

  4. File list: Pol.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.50.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.50.AllAg.iPS_cells.bed ...

  5. File list: DNS.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.20.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX135563,SRX040377,SRX040376,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.20.AllAg.iPS_cells.bed ...

  6. File list: DNS.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.10.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX040377,SRX040376,SRX135563,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.10.AllAg.iPS_cells.bed ...

  7. File list: Pol.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.05.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX027462,SRX977434 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.05.AllAg.iPS_cells.bed ...

  8. File list: ALL.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.10.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX753...09,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.10.AllAg.iPS_cells.bed ...

  9. File list: His.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.10.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127372,SRX1090869,SRX127376,SRX035977,SRX146530,SRX146547,SRX146522 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.10.AllAg.iPS_cells.bed ...

  10. File list: Oth.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.20.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX97...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.20.AllAg.iPS_cells.bed ...

  11. File list: DNS.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.05.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX040377,SRX040376,SRX135563,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.05.AllAg.iPS_cells.bed ...

  12. File list: His.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.20.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX127389,SR...RX127372,SRX127373,SRX1090869,SRX127376,SRX146530,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.20.AllAg.iPS_cells.bed ...

  13. Genomic imprinting is variably lost during reprogramming of mouse iPS cells.

    Science.gov (United States)

    Takikawa, Sachiko; Ray, Chelsea; Wang, Xin; Shamis, Yulia; Wu, Tien-Yuan; Li, Xiajun

    2013-09-01

    Derivation of induced pluripotent stem (iPS) cells is mainly an epigenetic reprogramming process. It is still quite controversial how genomic imprinting is reprogrammed in iPS cells. Thus, we derived multiple iPS clones from genetically identical mouse somatic cells. We found that parentally inherited imprint was variably lost among these iPS clones. Concurrent with the loss of DNA methylation imprint at the corresponding Snrpn and Peg3 imprinted regions, parental origin-specific expression of the Snrpn and Zim1 imprinted genes was also lost in these iPS clones. This loss of parental genomic imprinting in iPS cells was likely caused by the reprogramming process during iPS cell derivation because extended culture of iPS cells did not lead to significant increase in the loss of genomic imprinting. Intriguingly, one to several paternal chromosomes appeared to have acquired de novo methylation at the Snrpn and Zac1 imprinted regions in a high percentage of iPS clones. These results might have some implications for future therapeutic applications of iPS cells. Since DNA methylation imprint can be completely erased in some iPS clones at multiple imprinted regions, iPS cell reprogramming may also be employed to dissect the underlying mechanisms of erasure, reacquisition and maintenance of genomic imprinting in mammals. Copyright © 2013. Published by Elsevier B.V.

  14. File list: Oth.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.10.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX65...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.10.AllAg.iPS_cells.bed ...

  15. File list: His.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.05.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127374,SRX127373,SRX1090869,SRX333561,SRX146530,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.05.AllAg.iPS_cells.bed ...

  16. File list: ALL.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.10.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9774...30,SRX146524,SRX146547,SRX146522 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.10.AllAg.iPS_cells.bed ...

  17. File list: ALL.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.50.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9773...1,SRX035985,SRX1090869 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.50.AllAg.iPS_cells.bed ...

  18. File list: ALL.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.20.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9773...30,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.20.AllAg.iPS_cells.bed ...

  19. File list: His.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.20.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110015,S...315,SRX381309 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.20.AllAg.iPS_cells.bed ...

  20. File list: Oth.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.05.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX65...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.05.AllAg.iPS_cells.bed ...

  1. File list: DNS.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.50.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX135563,SRX040376,SRX040377,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.50.AllAg.iPS_cells.bed ...

  2. Ser-261 phospho-regulation is involved in pS256 and pS269-mediated aquaporin-2 apical translocation.

    Science.gov (United States)

    Yui, Naofumi; Ando, Fumiaki; Sasaki, Sei; Uchida, Shinichi

    2017-08-26

    Vasopressin catalyzes aquaporin-2 phosphorylation at several serine sites in the C-terminal region. Compared with Ser-256 and Ser-269 phosphorylation, the role of Ser-261 phospho-regulation on vasopressin-regulated AQP2 apical translocation is largely unknown. In addition, recent discovery of transcytotic apical delivery of AQP2 made the concept of its intracellular trafficking even more complicated. In this study, we evaluated how intact phospho-AQP2 signals fit with the transcytosis trafficking model in Madin-Darby canine kidney cells. PS256 and pS269 signals were intracellularly detectable in wild-type AQP2 at the beginning of forskolin stimulation (1 min). These phospho-signals were detectable in basolateral membranes even after 10 min of stimulation. AQP2 stably inserted in the apical membrane increased pS269 and decreased pS261 signals. In an NDI-causing mutant P262L-AQP2, in which Ser-261 phospho-regulation is impaired, the pS256 and pS269 signals were detectable in the basolateral membranes with increased pS261 signals after forskolin stimulation. These results suggest that Ser-261 phospho-regulation is involved in pS256- and pS269-mediated AQP2 apical translocation. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Chemistry, Poetry, and Artistic Illustration: An Interdisciplinary Approach to Teaching and Promoting Chemistry

    Science.gov (United States)

    Furlan, Ping Y.; Kitson, Herbert; Andes, Cynthia

    2007-10-01

    This article describes a successful interdisciplinary collaboration among chemistry, humanities and English faculty members, who utilized poetry and artistic illustration to help students learn, appreciate, and enjoy chemistry. Students taking general chemistry classes were introduced to poetry writing and museum-type poster preparation during one class period. They were then encouraged to use their imagination and creativity to brainstorm and write chemistry poems or humors on the concepts and principles covered in the chemistry classes and artistically illustrate their original work on posters. The project, 2 3 months in length, was perceived by students as effective at helping them learn chemistry and express their understanding in a fun, personal, and creative way. The instructors found students listened to the directives because many posters were witty, clever, and eye-catching. They showed fresh use of language and revealed a good understanding of chemistry. The top posters were created by a mix of A-, B-, and C-level students. The fine art work, coupled with poetry, helped chemistry come alive on campus, providing an aesthetic presentation of materials that engaged the general viewer.

  4. Radiation chemistry comes before radiation biology.

    Science.gov (United States)

    O'Neill, Peter; Wardman, Peter

    2009-01-01

    This article seeks to illustrate some contributions of radiation chemistry to radiobiology and related science, and to draw attention to examples where radiation chemistry is central to our knowledge of specific aspects. Radiation chemistry is a mature branch of radiation science which is continually evolving and finding wider applications. This is particularly apparent in the study of the roles of free radicals in biology generally, and radiation biology specifically. The chemical viewpoint helps unite the spatial and temporal insight coming from radiation physics with the diversity of biological responses. While historically, the main application of radiation chemistry of relevance to radiation biology has been investigations of the free-radical processes leading to radiation-induced DNA damage and its chemical characterization, two features of radiation chemistry point to its wider importance. First, its emphasis on quantification and characterization at the molecular level helps provide links between DNA damage, biochemical repair processes, and mutagenicity and radiosensitivity. Second, its central pillar of chemical kinetics aids understanding of the roles of 'reactive oxygen species' in cell signalling and diverse biological effects more generally, and application of radiation chemistry in the development of drugs to enhance radiotherapy and as hypoxia-specific cytotoxins or diagnostic agents. The illustrations of the broader applications of radiation chemistry in this article focus on their relevance to radiation biology and demonstrate the importance of synergy in the radiation sciences. The past contributions of radiation chemistry to radiation biology are evident, but there remains considerable potential to help advance future biological understanding using the knowledge and techniques of radiation chemistry.

  5. Collagen birefringence assessment in heart chordae tendineae through PS-OCT

    Science.gov (United States)

    Real, Eusebio; Revuelta, José M.; González-Vargas, Nieves; Pontón, Alejandro; Calvo-Díez, Marta; López-Higuera, José M.; Conde, Olga M.

    2017-02-01

    Degenerative mitral regurgitation is a serious and frequent human heart valve disease. Malfunctioning of this valve brings the left-sided heart through a significant increase of pressure and volume overload. Severe degenerative mitral incompetence generally requires surgical repair or valve replacement with a bioprosthesis or mechanical heart valve. Degenerative disease affects the leaflets or/and the chordae tendineae, which link both leaflets to the papillary muscles. During mitral valve surgical repair, reconstruction of the valve leaflets, annulus and chordae are provided to prevent postoperative recurrence of valve regurgitation. The operative evaluation of the diseased and apparently normal chordae tendineae mainly depends of the surgeońs experience, without any other objective diagnosis tool. In this work, PS-OCT (Polarization Sensitive-Optical Coherence Tomography) is applied for the first time to evaluate the pathological condition of human chordae coming from the mitral valve. It consists on a prospective study to test the viability of this technique for the evaluation of the collagen core of chords. This core presents a strong birefringence due to the longitudinal and organized arrangement of its collagen bundles. Different densities and organizations of the collagen core translate into different birefringence indicators whose measurement become an objective marker of the core structure. Ex-vivo mitral degenerative chordae tendineae have been analyzed with PS-OCT. Intensity OCT is used to obtain complementary morphological information of the chords. Birefringence results correlate with the previously reported values for human tendinous tissue.

  6. I. Cognitive and Instructional Factors Relating to Students' Development of Personal Models of Chemical Systems in the General Chemistry Laboratory II. Solvation in Supercritical Carbon Dioxide/Ethanol Mixtures Studied by Molecular Dynamics Simulation

    Science.gov (United States)

    Anthony, Seth

    2014-01-01

    Part I: Students' participation in inquiry-based chemistry laboratory curricula, and, in particular, engagement with key thinking processes in conjunction with these experiences, is linked with success at the difficult task of "transfer"--applying their knowledge in new contexts to solve unfamiliar types of problems. We investigate…

  7. Create and Publish a Hierarchical Progressive Survey (HiPS)

    Science.gov (United States)

    Fernique, P.; Boch, T.; Pineau, F.; Oberto, A.

    2014-05-01

    Since 2009, the CDS promotes a method for visualizing based on the HEALPix sky tessellation. This method, called “Hierarchical Progressive Survey" or HiPS, allows one to display a survey progressively. It is particularly suited for all-sky surveys or deep fields. This visualization method is now integrated in several applications, notably Aladin, the SiTools/MIZAR CNES framework, and the recent HTML5 “Aladin Lite". Also, more than one hundred surveys are already available in this view mode. In this article, we will present the progress concerning this method and its recent adaptation to the astronomical catalogs such as the GAIA simulation.

  8. Electrostatic septum for "Continuous Transfer" from PS to SPS

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    For "Continuous Transfer" to the SPS, the PS beam, after acceleration, is peeled off in 5 turns. To minimize losses, the magnetic septa are preceded by an electrostatic septum in straight section 31. We see the inner part of it, on a lab-bench. The first part consists of W-wires, the second part is a Mo-foil. The circulating beam passes through the opening, the ejected beam at the outside (above the wires, in this picture). This assembly is the anode-part, the cathode is not shown.

  9. Beam Quality Preservation in the CERN PS-SPS Complex

    CERN Multimedia

    Arduini, Gianluigi

    2004-01-01

    The LHC will require beams of unprecedented transverse and longitudinal brightness. Their production imposes tight constraints on the emittance growth in each element of the LHC injector chain, namely the PS-SPS Accelerator Complex. The problems encountered at the different stages of the acceleration in the complex span a wide range of topics, such as injection matching, RF gymnastics, space charge, transverse and longitudinal single- and coupled-bunch instabilities, and electron cloud effects. The measurement techniques developed and applied to identify and study the various sources of emittance dilution to the high precision required for the LHC beams and the solutions found to control such phenomena are illustrated.

  10. Lo irreductible social y lo irreductible psíquico

    Directory of Open Access Journals (Sweden)

    Vincent Gaulejac, de

    2017-06-01

    Full Text Available Con base en la reconstrucción de las polaridades explicativas -lo irreductible social y lo irreductible psíquico-que atraviesan a las ciencias sociales, este texto propone trascender los modelos antagónicos y excluyentes. El objetivo es instaurar en el centro de la reflexión la idea de la dialktica existencial que restituye al sujeto tanto el contexto socio-histórico en el cual está localizado como el deseo y la singularidad que lo constituyen en productor de la afirmación de su individualidad y su historicidad.

  11. PS potential performance with a higher injection energy

    CERN Document Server

    Gilardoni, S; Borburgh, J; Bodart, D; Chiggiato, P; Damerau, H; Hancock, S; Metral, G; Pittet, S; Rossi, C; Rumolo, G; Steerenberg, R; Widorski, M

    2011-01-01

    In the context of the LHC Injectors upgrade project, the PS has to be brought up to − and to operate reliably at − the level of performance required by the HL-LHC until the end of the LHC lifetime. The study has started on the potential benefits of increasing the injection energy. An overview of the impact of this upgrade will be presented, with a preliminary estimate of the beam characteristics at the SPS entrance and the remaining performance limitations. The necessary hardware modifications will be described, highlighting the critical systems and the risks. The program for the 2011 machine studies and hardware interventions for refining these plans will be presented.

  12. Injection and transfer lines of the PS Booster

    CERN Multimedia

    Photographic Service

    1972-01-01

    In the foreground is the vacuum chamber for the 50 MeV proton beam coming from the Linac. The tank held by white frames houses the "Vertical Distributor", which deflects the Linac beam to the levels of the Booster's 4 superposed rings. After acceleration in the Booster, originally to 800 MeV, today to 1.4 GeV, the beams from the 4 rings are combined in the vertical plane and transfered to the 26 GeV PS. The "Recombination Line", intersecting the injection line, crosses the picture from left to right.

  13. Search for Decays of Heavy Neutrinos with the PS Beam

    CERN Multimedia

    2002-01-01

    The experiment searches for neutrino decay, primarily into the e|+e|-@n^e and @g@g@n^e modes. Neutrino masses in the region between 1 and 400~MeV will be explored. The beam used is the neutrino PS beam used for the oscillation experiments. The apparatus consists of a decay volume @=30~m long and a calorimeter @=8~radiation lengths thick and @=20~m|2 in surface. The detectors are flash-tube modules of the type developed at Saclay for the proton-stability experiment. Scintillator hodoscopes give the timing information necessary for the trigger logic and background rejection.

  14. Reliability and maintenance analysis of the CERN PS booster

    CERN Document Server

    Staff, P S B

    1977-01-01

    The PS Booster Synchrotron being a complex accelerator with four superposed rings and substantial additional equipment for beam splitting and recombination, doubts were expressed at the time of project authorization as to its likely operational reliability. For 1975 and 1976, the average down time was 3.2% (at least one ring off) or 1.5% (all four rings off). The items analysed are: operational record, design features, maintenance, spare parts policy, operating temperature, effects of thunderstorms, fault diagnostics, role of operations staff and action by experts. (15 refs).

  15. Viscometric characterization of PS/POSS hybrid nanocomposites

    OpenAIRE

    Bianchi, Otávio; Repenning, Gustavo B.; Mauler, Raquel S.; Oliveira, Ricardo V. B.; Canto, Leonardo B.

    2012-01-01

    Nanocompósitos híbridos de poliestireno (PS) e poliedros oligoméricos silsesquioxanos (POSS) com diferentes composições e graus de hibridização foram obtidos por processamento reativo no estado fundido utilizando-se peróxido de dicumila (DCP) como iniciador, na presença ou não de estireno como agente de transferência de radical. Os materiais foram caracterizados viscosimetricamente por cromatografia de permeação em gel (GPC) usando detecção tripla por espalhamento de luz, viscosimetria e índi...

  16. Journal of Business Chemistry

    OpenAIRE

    2013-01-01

    The Journal of Business Chemistry examines issues associated with leadership and management for chemists and managers working in chemical research or industry. This journal is devoted to improving and developing the field of Business Chemistry. The Journal of Business Chemistry publishes peer-reviewed papers (including case studies) and essays. Areas for possible publication in include: leadership issues in the chemical and biochemical industry, such as teamwork, team building, mentoring, coa...

  17. Orbital interactions in chemistry

    CERN Document Server

    Albright, Thomas A; Whangbo, Myung-Hwan

    2013-01-01

    Explains the underlying structure that unites all disciplines in chemistry Now in its second edition, this book explores organic, organometallic, inorganic, solid state, and materials chemistry, demonstrating how common molecular orbital situations arise throughout the whole chemical spectrum. The authors explore the relationships that enable readers to grasp the theory that underlies and connects traditional fields of study within chemistry, thereby providing a conceptual framework with which to think about chemical structure and reactivity problems. Orbital Interactions

  18. USSR Report, Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    This USSR Report on Chemistry contains articles on Aerosols, Adsorption, Biochemistry, Catalysis, Chemical Industry, Coal Gasification, Electrochemistry, Explosives and Explosions, Fertilizers, Food...

  19. Advances in quantum chemistry

    CERN Document Server

    Sabin, John R

    2013-01-01

    Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine.Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features

  20. Canopy Chemistry (OTTER)

    Data.gov (United States)

    National Aeronautics and Space Administration — Canopy characteristics: leaf chemistry, specific leaf area, LAI, PAR, IPAR, NPP, standing biomass--see also: Meteorology (OTTER) for associated meteorological...

  1. Solution phase combinatorial chemistry.

    Science.gov (United States)

    Merritt, A T

    1998-06-01

    Combinatorial chemistry and parallel array synthesis techniques are now used extensively in the drug discovery process. Although published literature has been dominated by solid phase chemistry approaches, the use of solution phase techniques has also been widely explored. This review considers the advantages and disadvantages of choosing solution phase approaches in the various stages of drug discovery and optimisation, and assesses the practical issues related to these approaches. The uses of standard solution chemistry, the related liquid phase approach, and of supported materials to enhance solution phase chemistry are all illustrated by a comprehensive review of the published literature over the past three years.

  2. Elements of environmental chemistry

    National Research Council Canada - National Science Library

    Hites, R. A; Raff, Jonathan D

    2012-01-01

    ... more. Extensively revised, updated, and expanded, this second edition includes new chapters on atmospheric chemistry, climate change, and polychlorinated biphenyls and dioxins, and brominated flame retardants...

  3. Computational Chemistry for Kids

    National Research Council Canada - National Science Library

    Naef, Olivier

    2000-01-01

    This article aims to show that computational chemistry is not exclusively restricted to molecular energy and structure calculations but also includes chemical process control and reaction simulation...

  4. Green Chemistry Pedagogy

    Science.gov (United States)

    Kolopajlo, Larry

    2017-02-01

    This chapter attempts to show how the practice of chemistry teaching and learning is enriched by the incorporation of green chemistry (GC) into lectures and labs. To support this viewpoint, evidence from a wide range of published papers serve as a cogent argument that GC attracts and engages both science and nonscience students, enhances chemistry content knowledge, and improves the image of the field, while preparing the world for a sustainable future. Published pedagogy associated with green and sustainable chemistry is critically reviewed and discussed.

  5. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues

    Science.gov (United States)

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-01-01

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation. PMID:26888607

  6. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues.

    Science.gov (United States)

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-02-18

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation.

  7. [Induced pluripotent stem (iPS) cell - issues for clinical application - ].

    Science.gov (United States)

    Aoi, Takashi

    2013-01-01

    Induced pluripotent stem (iPS) cells are generated from somatic cells by introducing small sets of transcription factors. iPS cells demonstrate pluripotency and the ability to self-renew. In addition, iPS cells can be generated from donor individuals with particular characteristics. Based on these features, iPS cells are expected to be applicable in drug discovery, the study of disease mechanisms and cell therapy. From a technical point of view, "diversity" is the key word. At present, iPS cells can be derived using various techniques, resulting in diversity in the quality of iPS cells generated. Therefore, optimization of the derivation technology is one of the most important issues. Another "diversity" is in the propensities amongst iPS cell lines derived using similar techniques. Thus, strategies for selecting good quality lines remain to be established. Considering such technical hurdles, establishment of an iPS cell bank consisting of high quality and versatile iPS lines is a promising idea because of the merits of cost and quality control. Now, we are exploring relevant parameters for the quality control of banked cells. The challenges facing clinical application of iPS cells are new but not unprecedented. To realize clinical applications of iPS cells, we need to make these challenges clear and overcome them through partnership not only with industry, governments and universities, but also patients and society at large.

  8. Cytokine-producing microglia have an altered beta-amyloid load in aged APP/PS1 Tg mice

    DEFF Research Database (Denmark)

    Babcock, Alicia A; Ilkjær, Laura; Clausen, Bettina H

    2015-01-01

    Beta-amyloid (Aβ) plaques and chronic neuroinflammation are significant neuropathological features of Alzheimer's disease. Microglial cells in aged brains have potential to produce cytokines such as TNF and IL-1 family members (IL-1α, IL-1β, and IL-1Ra) and to phagocytose Aβ in Alzheimer's disease...... of CD11b, TNF, and IL-1Ra. Cytokine production and Aβ load were assessed in neocortical CD11b(+)(CD45(+)) microglia by flow cytometry. Whereas most microglia in aged mice produced IL-1Ra, relatively low proportions of microglia produced TNF, IL-1α, and IL-1β. However, microglial production...... of these latter cytokines was generally increased in APP/PS1 Tg mice. Microglia that phagocytosed endogenously-produced Aβ were only observed in APP/PS1 Tg mice. Differences in phagocytic index and total Aβ load were observed in microglia with specific cytokine profiles. Both phagocytic index and total Aβ load...

  9. What Does the Acid Ionization Constant Tell You? An Organic Chemistry Student Guide

    Science.gov (United States)

    Rossi, Robert D.

    2013-01-01

    Many students find the transition from first-year general chemistry to second-year organic chemistry a daunting task. There are many reasons for this, not the least of which is their lack of a solid understanding and appreciation of the importance of some basic concepts and principles from general chemistry that play an extremely critical role in…

  10. Methods for iPS cell generation for basic research and clinical applications.

    Science.gov (United States)

    Mochiduki, Yuji; Okita, Keisuke

    2012-06-01

    The induction of pluripotency can be achieved by forced expression of defined factors in somatic cells. The established cells, termed induced pluripotent stem (iPS) cells, have pluripotency and an infinite capacity for self-renewal in common with embryonic stem (ES) cells. Patient-specific iPS cells could be a useful source for drug discovery and cell transplantation therapies; however, the original method for iPS cell generation had several issues that were obstacles to their clinical application. Recent studies have brought about various improvements for iPS cell generation and uncovered several characteristics of iPS cells. Here we summarize the current status of iPS cell studies, with a focus on the improved methods that can be used to generate iPS cells, and also refer to the future challenges. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Differences in clinical chemistry values according to the use of two laxatives for colonoscopy.

    Science.gov (United States)

    Jeong, Seri; Lee, Sang-Guk; Kim, Yoonjung; Park, Jeong Rae; Kim, Jeong-Ho

    2014-08-01

    Polyethylene glycol-electrolyte lavage solutions (PEG-ELSs) and sodium phosphate formulations (NaPs) are two major colon cleansing laxatives used in preparation for endoscopic examinations of the gastrointestinal tract. PEG-ELSs are osmotically balanced preparations, whereas NaPs are hyperosmotic purgatives. This study aimed to evaluate the effects of these two laxatives on routine chemistry tests. We retrospectively reviewed 9366 clinical records of patients who had health checkups with or without colonoscopy from July 2010 to June 2011. We compared the values of 19 clinical chemistry parameters in the NaPs group (n=3239) and the PEG-ELSs group (n=1279) with those of controls (without colonoscopy, n=4848). Compared with controls, the NaPs group had higher mean values of inorganic phosphate, sodium, chloride, creatinine, total protein, AST, and ALT, and lower mean values of calcium and potassium, exceeding acceptable biases. Notably, inorganic phosphate showed the largest % bias (51.14%). In the PEG-ELSs laxative group, higher mean values of inorganic phosphorus, creatinine, uric acid, AST, and total bilirubin and a lower mean value of potassium were observed compared with controls, exceeding acceptable biases. The effects of NaPs on inorganic phosphate, calcium, and electrolyte levels exceeded those of PEG-ELSs. PEG-ELSs rather than NaPs are recommended as the first choice for bowel preparation, taking safety concerns and the reliability of laboratory values into account. Blood chemistry data from blood samples drawn after the ingestion of laxatives for colonoscopy should be interpreted with caution. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  12. Properties of Extruded PS-212 Type Self-Lubricating Materials

    Science.gov (United States)

    Waters, W. J.; Sliney, H. E.; Soltis, R. F.

    1993-01-01

    Research has been underway at the NASA Lewis Research Center since the 1960's to develop high temperature, self-lubricating materials. The bulk of the research has been done in-house by a team of researchers from the Materials Division. A series of self-lubricating solid material systems has been developed over the years. One of the most promising is the composite material system referred to as PS-212 or PM-212. This material is a powder metallurgy product composed of metal bonded chromium carbide and two solid lubricating materials known to be self-lubricating over a wide temperature range. NASA feels this material has a wide potential in industrial applications. Simplified processing of this material would enhance its commercial potential. Processing changes have the potential to reduce processing costs, but tribological and physical properties must not be adversely affected. Extrusion processing has been employed in this investigation as a consolidation process for PM-212/PS-212. It has been successful in that high density bars of EX-212 (extruded PM-212) can readily be fabricated. Friction and strength data indicate these properties have been maintained or improved over the P.M. version. A range of extrusion temperatures have been investigated and tensile, friction, wear, and microstructural data have been obtained. Results indicate extrusion temperatures are not critical from a densification standpoint, but other properties are temperature dependent.

  13. Phase morphological study on SEBS compatibilized PS/LDPE blends

    Directory of Open Access Journals (Sweden)

    Chatchai Kunyawut

    2014-09-01

    Full Text Available The co-continuous phase morphology of polystyrene (PS/low density polyethylene (LDPE blends compatibilized with poly(styrene-block-ethylene/butylene-block-styrene triblock copolymers (SEBS with varying molecular weights has been investigated. The blend samples were prepared in a mini-twin screw extruder. The barrel length and diameter are 224 and 16 mm, respectively. The diameter of the capillary die is 1 mm. The concentration of the blends was 70/30 wt% of PS/LDPE while that of the SEBS used was 5 wt% of the blend. The mixing temperatures used were 180, 250, and 280o C, and a screw speed of 60 rpm. The morphology of the blends was investigated using an AFM technique. Average droplet diameters of the blend samples were determined using an OM technique. The co-continuous morphology has not been obtained in all the blends, although the mixing temperature used is as high as 280o C. The experimental results indicated that the model prediction of the co-continuous morphology proposed by Willemse and co-worker was not applicable to the blend systems studied. Only droplet-type dispersion was observed. This is considered to arise from the processing conditions and the mixing device used. The blend compatibilized with the high molecular weight SEBS had higher dispersed phase size than that of the blend compatibilized with the medium and low molecular weight SEBSs. This behaviour is likely to arise from coalescence during melt processing.

  14. Preparations for Upgrading the RF Systems of the PS Booster

    CERN Document Server

    Albright, Simon; Shaposhnikova, Elena

    2016-01-01

    The accelerators of the LHC injector chain need to be upgraded to provide the HL-LHC beams. The PS Booster, the first synchrotron in the LHC injection chain, uses three different RF systems (first, second and up to tenth harmonic) in each of its four rings. As part of the LHC Injector Upgrade the current ferrite RF systems will be replaced with broadband Finemet cavities, increasing the flexibility of the RF system. A Finemet test cavity has been installed in Ring 4 to investigate its effect on machine performance, especially beam stability, during extensive experimental studies. Due to large space charge impedance Landau damping is lost through most of the cycle in single harmonic operation, but is recovered when using the second harmonic and controlled longitudinal emittance blow-up. This paper compares beam parameters during acceleration with and without the Finemet test cavity. Comparisons were made using beam measurements and simulations with the BLonD code based on a full PS Booster impedance model. Thi...

  15. KSR-based medium improves the generation of high-quality mouse iPS cells.

    Science.gov (United States)

    Liu, Kai; Wang, Fang; Ye, Xiaoying; Wang, Lingling; Yang, Jiao; Zhang, Jingzhuo; Liu, Lin

    2014-01-01

    Induced pluripotent stem (iPS) cells from somatic cells have great potential for regenerative medicine. The efficiency in generation of iPS cells has been significantly improved in recent years. However, the generation of high-quality iPS cells remains of high interest. Consistently, we demonstrate that knockout serum replacement (KSR)-based medium accelerates iPS cell induction and improves the quality of iPS cells, as confirmed by generation of chimeras and all iPS cell-derived offspring with germline transmission competency. Both alkaline phosphatase (AP) activity assay and expression of Nanog have been used to evaluate the efficiency of iPS cell induction and formation of ES/iPS cell colonies; however, appropriate expression of Nanog frequently indicates the quality of ES/iPS cells. Interestingly, whereas foetal bovine serum (FBS)-based media increase iPS cell colony formation, as revealed by AP activity, KSR-based media increase the frequency of iPS cell colony formation with Nanog expression. Furthermore, inhibition of MAPK/ERK by a specific inhibitor, PD0325901, in KSR- but not in FBS-based media significantly increases Nanog-GFP+ iPS cells. In contrast, addition of bFGF in KSR-based media decreases proportion of Nanog-GFP+ iPS cells. Remarkably, PD can rescue Nanog-GFP+ deficiency caused by bFGF. These data suggest that MAPK/ERK pathway influences high quality mouse iPS cells and that KSR- and PD-based media could enrich homogeneous authentic pluripotent stem cells.

  16. Bioinorganic Chemistry of the Alkali Metal Ions.

    Science.gov (United States)

    Kim, Youngsam; Nguyen, Thuy-Tien T; Churchill, David G

    2016-01-01

    The common Group 1 alkali metals are indeed ubiquitous on earth, in the oceans and in biological systems. In this introductory chapter, concepts involving aqueous chemistry and aspects of general coordination chemistry and oxygen atom donor chemistry are introduced. Also, there are nuclear isotopes of importance. A general discussion of Group 1 begins from the prevalence of the ions, and from a comparison of their ionic radii and ionization energies. While oxygen and water molecule binding have the most relevance to biology and in forming a detailed understanding between the elements, there is a wide range of basic chemistry that is potentially important, especially with respect to biological chelation and synthetic multi-dentate ligand design. The elements are widely distributed in life forms, in the terrestrial environment and in the oceans. The details about the workings in animal, as well as plant life are presented in this volume. Important biometallic aspects of human health and medicine are introduced as well. Seeing as the elements are widely present in biology, various particular endogenous molecules and enzymatic systems can be studied. Sodium and potassium are by far the most important and central elements for consideration. Aspects of lithium, rubidium, cesium and francium chemistry are also included; they help in making important comparisons related to the coordination chemistry of Na(+) and K(+). Physical methods are also introduced.

  17. Modern Trends in Inorganic Chemistry

    Indian Academy of Sciences (India)

    Unknown

    projections of research in frontier areas of inorganic chemistry, includ- ing organometallics, bio-inorganic chemistry, catalysis and materials chemistry. We do hope that the wide range of topics covered in this Issue reflect the current trends of research in inorganic chemistry in India and prac- titioners of inorganic chemistry ...

  18. Optimization of protease production by an actinomycete Strain, PS ...

    African Journals Online (AJOL)

    STORAGESEVER

    myecete proteases in the bio-organic chemistry. Like most other microbial proteases, those from .... Various aminoacids for protease production. Gelatin broth was used for studying the influence of organic matter .... Fungicidal activity of marine actinomycetes against phyotopathogenic fungi. Indian J. Biotechnol. 4: 271-276.

  19. MicroRNA expression profiles of human iPS cells, retinal pigment epithelium derived from iPS, and fetal retinal pigment epithelium.

    Science.gov (United States)

    Greene, Whitney A; Muñiz, Alberto; Plamper, Mark L; Kaini, Ramesh R; Wang, Heuy-Ching

    2014-06-24

    The objective of this report is to describe the protocols for comparing the microRNA (miRNA) profiles of human induced-pluripotent stem (iPS) cells, retinal pigment epithelium (RPE) derived from human iPS cells (iPS-RPE), and fetal RPE. The protocols include collection of RNA for analysis by microarray, and the analysis of microarray data to identify miRNAs that are differentially expressed among three cell types. The methods for culture of iPS cells and fetal RPE are explained. The protocol used for differentiation of RPE from human iPS is also described. The RNA extraction technique we describe was selected to allow maximal recovery of very small RNA for use in a miRNA microarray. Finally, cellular pathway and network analysis of microarray data is explained. These techniques will facilitate the comparison of the miRNA profiles of three different cell types.

  20. I. Cognitive and instructional factors relating to students' development of personal models of chemical systems in the general chemistry laboratory II. Solvation in supercritical carbon dioxide/ethanol mixtures studied by molecular dynamics simulation

    Science.gov (United States)

    Anthony, Seth

    Part I. Students' participation in inquiry-based chemistry laboratory curricula, and, in particular, engagement with key thinking processes in conjunction with these experiences, is linked with success at the difficult task of "transfer"---applying their knowledge in new contexts to solve unfamiliar types of problems. We investigate factors related to classroom experiences, student metacognition, and instructor feedback that may affect students' engagement in key aspects of the Model-Observe-Reflect-Explain (MORE) laboratory curriculum - production of written molecular-level models of chemical systems, describing changes to those models, and supporting those changes with reference to experimental evidence---and related behaviors. Participation in introductory activities that emphasize reviewing and critiquing of sample models and peers' models are associated with improvement in several of these key aspects. When students' self-assessments of the quality of aspects of their models are solicited, students are generally overconfident in the quality of their models, but these self-ratings are also sensitive to the strictness of grades assigned by their instructor. Furthermore, students who produce higher-quality models are also more accurate in their self-assessments, suggesting the importance of self-evaluation as part of the model-writing process. While the written feedback delivered by instructors did not have significant impacts on student model quality or self-assessments, students' resubmissions of models were significantly improved when students received "reflective" feedback prompting them to self-evaluate the quality of their models. Analysis of several case studies indicates that the content and extent of molecular-level ideas expressed in students' models are linked with the depth of discussion and content of discussion that occurred during the laboratory period, with ideas developed or personally committed to by students during the laboratory period being

  1. On the analysis of activation energy of PS 35000 in various solvents

    Science.gov (United States)

    Padmanaban, R.; Venkatramanan, K.

    2015-08-01

    Polymer is a macromolecule, composed of many repeated subunits. Polystyrene is a polymer of styrene. Polystyrene has very low impact strength. Polystyrene generally leads to lower tensile strength, crystal grades being stiff and brittle. It is used to construct clamshell packs, cookie trays, cups, forks, spoons, cushioning materials for packaging, disposable medical devices, egg cartons, fast food containers, lids, lunch boxes, meat trays and also used in civil construction (concrete form-work or weight reduction on foundations). In the present study an attempt has been made to compute the viscosity of Polystyrene (PS 35000) in toluene and benzene in different concentrations (0.5%, 1.0%, 1.5%, 2.0% & 2.5%) at different temperatures (303 K, 308 K, 313 K & 318 K). From these experimental data the activation energy is calculated and the effect of solvent is analysed.

  2. Diversity in Medicinal Chemistry.

    Science.gov (United States)

    Peralta, David

    2018-01-08

    The wide world of medicinal chemistry: We look back at our activities in 2017, particularly the expansion of the journal's scope to nanomedicine and why we need a more inclusive medicinal chemistry journal. Additionally, we look at upcoming special issues and developments for ChemPubSoc Europe in 2018. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Exercises in Computational Chemistry

    DEFF Research Database (Denmark)

    Spanget-Larsen, Jens

    2016-01-01

    A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16).......A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16)....

  4. Movies in Chemistry Education

    Science.gov (United States)

    Pekdag, Bulent; Le Marechal, Jean-Francois

    2010-01-01

    This article reviews numerous studies on chemistry movies. Movies, or moving pictures, are important elements of multimedia and signify a privileged or motivating means of presenting knowledge. Studies on chemistry movies show that the first movie productions in this field were devoted to university lectures or documentaries. Shorter movies were…

  5. Chemistry of americium

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, W.W.

    1976-01-01

    Essential features of the descriptive chemistry of americium are reviewed. Chapter titles are: discovery, atomic and nuclear properties, collateral reading, production and uses, chemistry in aqueous solution, metal, alloys, and compounds, and, recovery, separation, purification. Author and subject indexes are included. (JCB)

  6. Mars aqueous chemistry experiment

    Science.gov (United States)

    Clark, Benton C.; Mason, Larry W.

    1994-01-01

    Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. The second year of the MACE project has shown significant progress in two major areas. MACE Instrument concept definition is a baseline design that has been generated for the complete MACE instrument, including definition of analysis modes, mass estimates and thermal model. The design includes multiple reagent reservoirs, 10 discrete analysis cells, sample manipulation capability, and thermal control. The MACE Measurement subsystems development progress is reported regarding measurement capabilities for aqueous ion sensing, evolved gas sensing, solution conductivity measurement, reagent addition (titration) capabilities, and optical sensing of suspended particles.

  7. Bioscience methodologies in physical chemistry an engineering and molecular approach

    CERN Document Server

    D'Amore, Alberto

    2013-01-01

    The field of bioscience methodologies in physical chemistry stands at the intersection of the power and generality of classical and quantum physics with the minute molecular complexity of chemistry and biology. This book provides an application of physical principles in explaining and rationalizing chemical and biological phenomena. It does not stick to the classical topics that are conventionally considered as part of physical chemistry; instead it presents principles deciphered from a modern point of view, which is the strength of this book.

  8. Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate

    Science.gov (United States)

    Nagel, S. R.; Benedetti, L. R.; Bradley, D. K.; Hilsabeck, T. J.; Izumi, N.; Khan, S.; Kyrala, G. A.; Ma, T.; Pak, A.

    2016-11-01

    The dilation x-ray imager (DIXI) [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010); S. R. Nagel et al., ibid. 83, 10E116 (2012); S. R. Nagel et al., ibid. 85, 11E504 (2014)] is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10 × improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method [J. Salmon et al., J. Math. Imaging Vision 48, 279294 (2014)] to improve the robustness of the DIXI data analysis. Here we present results on ignition-relevant experiments at the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P0, P2, and P4 Legendre modes, and their temporal evolution/swings).

  9. Role of insulin receptor and insulin signaling on αPS2CβPS integrins' lateral diffusion.

    Science.gov (United States)

    Mainali, Dipak; Syed, Aleem; Arora, Neha; Smith, Emily A

    2014-12-01

    Integrins are ubiquitous transmembrane receptors with adhesion and signaling properties. The influence of insulin receptor and insulin signaling on αPS2CβPS integrins' lateral diffusion was studied using single particle tracking in S2 cells before and after reducing the insulin receptor expression or insulin stimulation. Insulin signaling was monitored by Western blotting for phospho-Akt expression. The expression of the insulin receptor was reduced using RNA interference (RNAi). After insulin receptor RNAi, four significant changes were measured in integrin diffusion properties: (1) there was a 24% increase in the mobile integrin population, (2) 14% of the increase was represented by integrins with Brownian diffusion, (3) for integrins that reside in confined zones of diffusion, there was a 45% increase in the diameter of the confined zone, and (4) there was a 29% increase in the duration integrins spend in confined zones of diffusion. In contrast to reduced expression of the insulin receptor, which alters integrin diffusion properties, insulin stimulation alone or insulin stimulation under conditions of reduced insulin receptor expression have minimal effects on altering the measured integrin diffusion properties. The differences in integrin diffusion measured after insulin receptor RNAi in the presence or absence of insulin stimulation may be the result of other insulin signaling pathways that are activated at reduced insulin receptor conditions. No change in the average integrin diffusion coefficient was measured for any conditions included in this study.

  10. Transuranic Computational Chemistry.

    Science.gov (United States)

    Kaltsoyannis, Nikolas

    2018-02-26

    Recent developments in the chemistry of the transuranic elements are surveyed, with particular emphasis on computational contributions. Examples are drawn from molecular coordination and organometallic chemistry, and from the study of extended solid systems. The role of the metal valence orbitals in covalent bonding is a particular focus, especially the consequences of the stabilization of the 5f orbitals as the actinide series is traversed. The fledgling chemistry of transuranic elements in the +II oxidation state is highlighted. Throughout, the symbiotic interplay of experimental and computational studies is emphasized; the extraordinary challenges of experimental transuranic chemistry afford computational chemistry a particularly valuable role at the frontier of the periodic table. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Biosynthetic inorganic chemistry.

    Science.gov (United States)

    Lu, Yi

    2006-08-25

    Inorganic chemistry and biology can benefit greatly from each other. Although synthetic and physical inorganic chemistry have been greatly successful in clarifying the role of metal ions in biological systems, the time may now be right to utilize biological systems to advance coordination chemistry. One such example is the use of small, stable, easy-to-make, and well-characterized proteins as ligands to synthesize novel inorganic compounds. This biosynthetic inorganic chemistry is possible thanks to a number of developments in biology. This review summarizes the progress in the synthesis of close models of complex metalloproteins, followed by a description of recent advances in using the approach for making novel compounds that are unprecedented in either inorganic chemistry or biology. The focus is mainly on synthetic "tricks" learned from biology, as well as novel structures and insights obtained. The advantages and disadvantages of this biosynthetic approach are discussed.

  12. Hydrogen sulfide down-regulates BACE1 and PS1 via activating PI3K/Akt pathway in the brain of APP/PS1 transgenic mouse.

    Science.gov (United States)

    He, Xuan-Li; Yan, Ning; Chen, Xiao-Shan; Qi, Yun-Wen; Yan, Yong; Cai, Zhiyou

    2016-10-01

    Endogenous hydrogen sulfide (H2S) may have multiple physiological functions in brain. Our previous study showed that H2S improved spatial memory impairment and decreased the production of Aβ in APP/PS1 transgenic mice. However, many of the underlying mechanisms are not still being elucidated. The aim of the present study is to investigate the neuroprotective mechanisms of H2S involving in the activity of β-secretase (BACE1), γ-secretase (PS1) and α-secretase (ADAM17). Morris water maze was used to measure the behavior change. The levels of Aβ40 and Aβ42 were quantified using colorimetric ELISA kits and immunohistochemical analysis. The levels of BACE1, PS1, ADAM17, pAkt, pp38MAPK, pERK and pJNK were tested by Western blot analysis in normal mice, APP/PS1 transgenic mice and 50μmol/kg-NaHS-treated transgenic mice. On the basis of exogenous H2S treatment, LY294002 (inhibitors of PI3K/Akt) or PD98059 (inhibitors of MAPK/ERK) was injected into lateral cerebral ventricle. The levels of BACE1, PS1 and pp38MAPK were increased and ADAM17 were decreased in the APP/PS1 transgenic mice. After intraperitoneal administration of an H2S donor (NaHS) into APP/PS1 mice, the levels of BACE1, PS1 and pp38MAPK were reduced and ADAM17 increased. The level of pp38 MAPKs, pAkt and pERK1/2 was increased in APP/PS1 transgenic mice compared with normal mice (ptransgenic mice and normal mice (p>0.05). These results demonstrated that LY294002 inhibited the effect of H2S on decreasing the BACE1 and PS1, reducing the level of Aβ and improving memory impairment in APP/PS1 transgenic mice. PD98059 had no influence on the expression of BACE1 and PS1. H2S inhibits the expression of BACE1 and PS1 by activating PI3K/Akt pathway in AD. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  13. Korean Kimchi Chemistry: A Multicultural Chemistry Connection

    Science.gov (United States)

    Murfin, Brian

    2009-01-01

    Connecting science with different cultures is one way to interest students in science, to relate science to their lives, and at the same time to broaden their horizons in a variety of ways. In the lesson described here, students make kimchi, a delicious and popular Korean dish that can be used to explore many important chemistry concepts,…

  14. Development and characterization of sub-100 ps photomultiplier tubes.

    Science.gov (United States)

    Horsfield, C J; Rubery, M S; Mack, J M; Young, C S; Herrmann, H W; Caldwell, S E; Evans, S C; Sedilleo, T J; Kim, Y H; McEvoy, A; Milnes, J S; Howorth, J; Davis, B; O'Gara, P M; Garza, I; Miller, E K; Stoeffl, W; Ali, Z

    2010-10-01

    We describe the evaluation of a microchannel plate (MCP) photomultiplier tube (PMT), incorporating a 3 μm pore MCP and constant voltage anode and cathode gaps. The use of the small pore size results in PMTs with response functions of the order of 85 ps full-width-half-maximum, while the constant electric field across the anode and cathode gaps produces a uniform response function over the entire operating range of the device. The PMT was characterized on a number of facilities and employed on gas Cherenkov detectors fielded on various deuterium tritium fuel (DT) implosions on the Omega Laser Facility at the University of Rochester. The Cherenkov detectors are part of diagnostic development to measure Gamma ray reaction history for DT implosions on the National Ignition Facility.

  15. An Antiproton Decelerator in the CERN PS Complex

    CERN Document Server

    Riunaud, J P; Baird, S A; Boillot, J; Bosser, Jacques; Brouet, M; Caspers, Friedhelm; Chanel, M; Chohan, V; Eriksson, T; Garoby, R; Giannini, R; Giovannozzi, Massimo; Gruber, J; Hémery, J Y; Koziol, Heribert; MacCaferri, R; Maury, S; Metzmacher, K D; Möhl, D; Mulder, H; Pedersen, F; Perriollat, F; Poncet, Alain; Riunaud, J P; Serre, C; Simon, Daniel Jean; Tranquille, G; Tuyn, Jan Willem Nicolaas; Williams, B; Williams, D J

    1996-01-01

    The present CERN PS low-energy antiproton complex involves 4 machines to collect, cool, decelerate and supply experiments with up to 1010 antiprotons per pulse and per hour of momenta ranging from 0.1 to 2 GeV/c. In view of a possible future physics programme requiring low energy antiprotons, mainly to carry out studies on antihydrogen, a simplified scheme providing at low cost antiprotons at 100 MeV/c has been studied. It requires only one machine, the present Antiproton Collector (AC) converted into a cooler and decelerator (Antiproton Decelerator, AD) and delivering beam to experiments in the hall of the present Antiproton Accumulator Complex (AAC) [1]. This paper describes the feasibility study of such a scheme [2].

  16. MD on Head-Tail Instability in the PS Booster

    CERN Document Server

    Kornilov, V; Mikulec, B; Aumon, S; Rumolo, G

    2013-01-01

    Machine study experiments on the coherent instabilities appearing along the magnetic ramp have been performed at the CERN PS Booster synchrotron in the week of June 11-15, 2012. The space- and time structure of the head-tail instabilities was recorded by the triggered pick-up signals due to reproducibility of the occurrence time in the shot-by-shot sense. The intensity thresholds, the absolute growth rates and the mode structure have been compared for the bunches in the single-rf and in three types of the double-rf operation. The growth rates are compared to the instantaneous synchrotron frequencies, in the cases of the large corresponding ratio the head-tail mode structure is deformed by the driving impedance. Bunch parameters measurements indicate that the PSB bunches are in the regime of very strong transverse space-charge all along the magnetic ramp.

  17. Multipole Stack for the 800 MeV PS Booster

    CERN Multimedia

    1975-01-01

    The 800 MeV PS Booster had seen first beam in its 4 superposed rings in 1972, routine operation began in 1973. In the strive for ever higher beam intensities, the need for additional multipole lenses became evident. After detailed studies, the manufacture of 8 stacks of multipoles was launched in 1974. Each stack consists of 4 superposed multipoles and each multipole has 4 concentric shells. From the innermost to the outermost shell, Type A contains octupole, skew-octupole, sextupole, skew-sextupole. Type B contains skew-octupole, skew-sextupole, vertical dipole, horizontal dipole. Completion of installation in 1976 opened the way to higher beam intensities. M. Battiaz is seen here with a multipole stack and its many electrical connections.

  18. First PS magnet unit, with members of the Magnet Group.

    CERN Multimedia

    CERN PhotoLab

    1956-01-01

    Members of the Magnet Group, sitting atop the first unit of the PS combined-function magnet. The picture was taken at the Institute of Physics of Geneva University, as CERN was still a muddy construction site at that time. All these people have now retired, but all of the magnets are still pulsing away. Front row (left to right): R.Tinguely, C.Germain, G.Plass, D.Neet, B.de Raad, M.Cavallaro, K.H.Reich, G.Kuhn, J.Nilsson, C.A.Ramm, Paillard. Second row: L.Resegotti, M.Niklaus, C.J.Zilverschoon, R.Bertolotto, Marcellin, G.Brianti, P.Collet. Standing behind: B.Kuiper.

  19. Surface morphology of PS-PDMS diblock copolymer films

    DEFF Research Database (Denmark)

    Andersen, T.H.; Tougaard, S.; Larsen, N.B.

    2001-01-01

    Spin coated thin films (∼400 Å) of poly(styrene)–poly(dimethylsiloxane) (PS–PDMS) diblock copolymers have been investigated using X-ray Photoelectron Spectroscopy and Atomic Force Microscopy. Surface segregation of the poly(dimethylsiloxane) blocks was studied for five diblock copolymers which...... by use of peak shape analysis of the X-ray Photoelectron Spectra via the Tougaard Method. The amount of dimethylsiloxane in the uppermost part of the films was quantified as a function of annealing time and temperature. For annealing above the PS glass transition temperature, surface segregation...... of the dimethylsiloxane chain-ends occurs for all the studied PS–PDMS diblock copolymers. At room temperature, surface segregation takes place only when the amount of dimethylsiloxane in the diblock copolymers is small....

  20. Sub-10ps monolithic and low-power photodetector readout

    Energy Technology Data Exchange (ETDEWEB)

    Varner, Gary S.; Ruckman, Larry L.

    2009-02-20

    Recent advances in photon detectors have resulted in high-density imaging arrays that offer many performance and cost advantages. In particular, the excellent transit time spread of certain devices show promise to provide tangible benefits in applications such as Positron Emission Tomography (PET). Meanwhile, high-density, high-performance readout techniques have not kept on pace for exploiting these developments. Photodetector readout for next generation high event rate particle identification and time-resolved PET requires a highly-integrated, low-power, and cost-effective readout technique. We propose fast waveform sampling as a method that meets these criteria and demonstrate that sub-10ps resolution can be obtained for an existing device.

  1. Small-size meshless 50 ps streak tube

    Science.gov (United States)

    Ageeva, N. V.; Andreev, S. V.; Belolipetski, V. S.; Bryukhnevich, G. I.; Greenfield, D. E.; Ivanova, S. R.; Kaverin, A. M.; Khohlova, A. N.; Kuz'menko, E. A.; Levina, G. P.; Makushina, V. A.; Monastyrskiy, M. A.; Schelev, M. Ya.; Semichastnova, Z. M.; Serdyuchenko, Yu. N.; Skaballanovich, T. A.; Sokolov, V. E.

    2008-11-01

    In contrast to the conventional image intensifier with large work area, a streak image tube should possess additional important feature - the comparatively small temporal distortion at the entire work area of the photocathode. With this additional engineering restriction taken into account, a novel small-size meshless streak image tube has been developed by means of numerical optimization. The tube with 25-mm wide work area contains a pair of deflection plates to sweep the electron image along the 25 mm output phosphor screen that is separated by 100 mm from the photocathode. The electron image can be shuttered with a 300 V blanking electric pulse. Electron-optical magnification of the tube is unit; spatial resolution reaches 30 lp/mm over the entire photocathode work area; temporal resolution lies in the 20 - 50 ps range, depending on the accelerating voltage (6 - 15 kV).

  2. Psödohipoparatiroidi Tip 1A: Olgu Sunumu

    Directory of Open Access Journals (Sweden)

    Mehmet Güven

    2017-06-01

    Full Text Available Psödohipoparatiroidizm (PHPT; hedef organın parathormona (PTH yanıt vermediği kalıtımsal bir bozukluktur. Biyokimyasal olarak; hipokalsemi, hiperfosfatemi ve PTH yüksekliği ile karakterizedir. PTH uygulamasına verilen yanıt belirgin derecede düşüktür. Tip 1A, biyokimyasal özelliklere ek olarak Albright herediter osteodistrofisi (AHO olarak bilinen karakteristik somatik bir fenotipe de sahiptir. Bu fenotipin, kısa boy, yuvarlak yüz, frontal bombelik, brakidaktili, obezite özelikleri bulunmaktadır. Burada biz, hipokalsemi ve Albright herediter osteodistrofisi tanısı koyduğumuz; kalsiyum, aktif D vitamini ile tedavi ettiğimiz olgumuzu sunduk.

  3. Enhancing efficacy and mucosa-tropic distribution of an oral HIV-PsV DNA vaccine in animal models.

    Science.gov (United States)

    Fu, Jie; Bian, Guangxing; Zhao, Bijun; Dong, Zengxiang; Sun, Xiao; Chen, Fang; Ou, Lun; Song, Haifeng

    2009-12-01

    A strategy combined the oral delivery route and bovine papillomavirus (BPV) pseudovirus (PsV)-based human immunodeficiency virus (HIV) DNA vaccine, which has been proven to enhance the mucosal immunization compared with the systemic immunization and in general does not induce effective mucosal immune responses. In this study, the immune responses against the BPV expressing HIV gp41 epitopes (ELDKWA, NWFDIT) after oral administration in Cynomolgus monkeys (Macaca fascicularis) were assessed, and the biodistribution of plasmid DNA encapsulated in the papillomavirus-like particles (VLPs) were evaluated in murine models. Results showed that oral immunization with the HIV-PsV DNA vaccine in monkey generated p24 and gp41 epitopes-specific serum IgG. Importantly, these induced antibodies had been shown to neutralize HIV-1 primary strain. In addition, the advantage of VLPs as vehicles delivering genes had been first revealed in biodistribution results. Therefore, orally administered HIV-PsV DNA vaccine was well-tolerated, enhanced the mucosa targeting property of the plasmid DNA, and reduced the nontargeting distribution, which indicate that it would reduce stress associated with systemic vaccination.

  4. Surface Chemistry in Nanoscale Materials

    Directory of Open Access Journals (Sweden)

    Alex V. Hamza

    2009-12-01

    Full Text Available Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface area materials such as nanoporous solids, surface properties can start to dominate the overall material behavior. This allows one to create new materials with physical and chemical properties that are no longer determined by the bulk material, but by their nanoscale architectures. Here, we discuss several examples, ranging from nanoporous gold to surface engineered carbon aerogels that demonstrate the tuneability of nanoporous solids for sustainable energy applications.

  5. Surface Chemistry in Nanoscale Materials

    Science.gov (United States)

    Biener, Jürgen; Wittstock, Arne; Baumann, Theodore F.; Weissmüller, Jörg; Bäumer, Marcus; Hamza, Alex V.

    2009-01-01

    Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface area materials such as nanoporous solids, surface properties can start to dominate the overall material behavior. This allows one to create new materials with physical and chemical properties that are no longer determined by the bulk material, but by their nanoscale architectures. Here, we discuss several examples, ranging from nanoporous gold to surface engineered carbon aerogels that demonstrate the tuneability of nanoporous solids for sustainable energy applications.

  6. Photoredox Catalysis in Organic Chemistry

    Science.gov (United States)

    2016-01-01

    In recent years, photoredox catalysis has come to the forefront in organic chemistry as a powerful strategy for the activation of small molecules. In a general sense, these approaches rely on the ability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single-electron transfer with organic substrates, thereby generating reactive intermediates. In this Perspective, we highlight the unique ability of photoredox catalysis to expedite the development of completely new reaction mechanisms, with particular emphasis placed on multicatalytic strategies that enable the construction of challenging carbon–carbon and carbon–heteroatom bonds. PMID:27477076

  7. Use of sequential infiltration synthesis to improve the pattern transfer of PS-b-PLA DSA (Conference Presentation)

    Science.gov (United States)

    Evangelio Araujo, Laura; Fernández-Regúlez, Marta; Chevalier, Xavier; Nicolet, Célia; Cayrefourcq, Ian; Navarro, Christophe; Fleury, Guillaume; Pérez-Murano, Francesc

    2017-03-01

    Directed self-assembly of block copolymers is considered one of the candidates to fulfill the requirements of the next technological nodes [1,2]. Polymer domains are aligned by using a chemical and/or a topographical pre-pattern in which preferential surfaces to one of the two blocks or neutral wetting areas are created. In particular, polystyrene-block-polymetylmethacrylate (PS-b-PMMA) has been extensively studied during the last years showing strong capabilities to define periodic nanostructures. However, the relatively low Flory-Huggins parameter and, the resulting low segregation strength of PS-b-PMMA systems, limit their achievable resolution to around 11 nm [3]. The application of block copolymer on sub-10 nm technologies requires the development of the new block copolymer generation known as high- block copolymers. Additionally, an important requirement for their integration on the lithography roadmap is the capability of selectively remove one of the two blocks. The etch contrast between the two domains is typically low due to their organic chemistry. In this sense, selective sequential infiltration synthesis by ALD into one of the blocks can be used in order to incorporate an inorganic material. The formed organic/inorganic blend sustains better the plasma etching to remove the non-infiltrated organic block. In this contribution, we show the use of high- polystyrene-b-polylactide acid (PS-b-PLA) lamellar block copolymer for line/space applications. PS-b-PLA has a larger Flory-Huggins parameter (=0.218 at room temperature[4]) compared with PS-b-PMMA, allowing the size reduction of the self-assembled domains. The method to control the orientation of the polymer domains is similar to the one typically used for PS-b-PMMA. Chemical contrast and the subsequent alignment of the polymer domains are achieved by the definition of a chemical pre-pattern on a random copolymer PS-r-PMMA (48% of PS) (figure 1). The polymer brush is grafted on the substrate and then

  8. Updating the Psoriatic Arthritis (PsA) Core Domain Set: A Report from the PsA Workshop at OMERACT 2016.

    Science.gov (United States)

    Orbai, Ana-Maria; de Wit, Maarten; Mease, Philip J; Callis Duffin, Kristina; Elmamoun, Musaab; Tillett, William; Campbell, Willemina; FitzGerald, Oliver; Gladman, Dafna D; Goel, Niti; Gossec, Laure; Hoejgaard, Pil; Leung, Ying Ying; Lindsay, Chris; Strand, Vibeke; van der Heijde, Désirée M; Shea, Bev; Christensen, Robin; Coates, Laura; Eder, Lihi; McHugh, Neil; Kalyoncu, Umut; Steinkoenig, Ingrid; Ogdie, Alexis

    2017-10-01

    To include the patient perspective in accordance with the Outcome Measures in Rheumatology (OMERACT) Filter 2.0 in the updated Psoriatic Arthritis (PsA) Core Domain Set for randomized controlled trials (RCT) and longitudinal observational studies (LOS). At OMERACT 2016, research conducted to update the PsA Core Domain Set was presented and discussed in breakout groups. The updated PsA Core Domain Set was voted on and endorsed by OMERACT participants. We conducted a systematic literature review of domains measured in PsA RCT and LOS, and identified 24 domains. We conducted 24 focus groups with 130 patients from 7 countries representing 5 continents to identify patient domains. We achieved consensus through 2 rounds of separate surveys with 50 patients and 75 physicians, and a nominal group technique meeting with 12 patients and 12 physicians. We conducted a workshop and breakout groups at OMERACT 2016 in which findings were presented and discussed. The updated PsA Core Domain Set endorsed with 90% agreement by OMERACT 2016 participants included musculoskeletal disease activity, skin disease activity, fatigue, pain, patient's global assessment, physical function, health-related quality of life, and systemic inflammation, which were recommended for all RCT and LOS. These were important, but not required in all RCT and LOS: economic cost, emotional well-being, participation, and structural damage. Independence, sleep, stiffness, and treatment burden were on the research agenda. The updated PsA Core Domain Set was endorsed at OMERACT 2016. Next steps for the PsA working group include evaluation of PsA outcome measures and development of a PsA Core Outcome Measurement Set.

  9. First observation of o-Ps to p-Ps transition and first direct measurement of positronium hyperfine splitting with sub-THz light

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Takayuki, E-mail: yamazaki@icepp.s.u-tokyo.ac.jp; Miyazaki, Akira; Suehara, Taikan; Namba, Toshio; Asai, Shoji; Kobayashi, Tomio [University of Tokyo, Department of Physics, Graduate School of Science, and International Center for Elementary Particle Physics (Japan); Saito, Haruo [University of Tokyo, Graduate School of Arts and Sciences (Japan); Urushizaki, Yuichi; Ogawa, Isamu; Idehara, Toshitaka [University of Fukui, Research Center for Development of Far-Infrared Region (Japan); Sabchevski, Svilen [Bulgarian Academy of Sciences (Bulgaria)

    2012-12-15

    Positronium is an ideal system for the research of the bound state QED. The hyperfine splitting of positronium (Ps-HFS, about 203 GHz) is an important observable but all previous measurements of Ps-HFS had been measured indirectly using Zeeman splitting. There might be the unknown systematic errors on the uniformity of magnetic field. We are trying to measure Ps-HFS directly using sub-THz radiation. We developed an optical system to accumulate high power (about 10 kW) radiation in a Fabry-Perot resonant cavity and observed the positronium hyperfine transition for the first time.

  10. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

  11. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  12. An Analysis of Prospective Chemistry Teachers' Cognitive Structures through Flow Map Method: The Subject of Oxidation and Reduction

    Science.gov (United States)

    Temel, Senar

    2016-01-01

    This study aims to analyse prospective chemistry teachers' cognitive structures related to the subject of oxidation and reduction through a flow map method. Purposeful sampling method was employed in this study, and 8 prospective chemistry teachers from a group of students who had taken general chemistry and analytical chemistry courses were…

  13. Assessing Student Knowledge of Chemistry and Climate Science Concepts Associated with Climate Change: Resources to Inform Teaching and Learning

    Science.gov (United States)

    Versprille, Ashley; Zabih, Adam; Holme, Thomas A.; McKenzie, Lallie; Mahaffy, Peter; Martin, Brian; Towns, Marcy

    2017-01-01

    Climate change is one of the most critical problems facing citizens today. Chemistry faculty are presented with the problem of making general chemistry content simultaneously relevant and interesting. Using climate science to teach chemistry allows faculty to help students learn chemistry content in a rich context. Concepts related to…

  14. Students' Understanding of Acids/Bases in Organic Chemistry Contexts

    Science.gov (United States)

    Cartrette, David P.; Mayo, Provi M.

    2011-01-01

    Understanding key foundational principles is vital to learning chemistry across different contexts. One such foundational principle is the acid/base behavior of molecules. In the general chemistry sequence, the Bronsted-Lowry theory is stressed, because it lends itself well to studying equilibrium and kinetics. However, the Lewis theory of…

  15. Molecular Modeling and Computational Chemistry at Humboldt State University.

    Science.gov (United States)

    Paselk, Richard A.; Zoellner, Robert W.

    2002-01-01

    Describes a molecular modeling and computational chemistry (MM&CC) facility for undergraduate instruction and research at Humboldt State University. This facility complex allows the introduction of MM&CC throughout the chemistry curriculum with tailored experiments in general, organic, and inorganic courses as well as a new molecular modeling…

  16. The Humanistic Psychology Movement and the Teaching of Chemistry.

    Science.gov (United States)

    Battino, Rubin

    1983-01-01

    Describes how several areas of humanistic psychology can be applied to college level chemistry in particular and teaching in general, focusing on confluent education in chemistry and neurolinguistic programing (including representational systems, anchoring, and neurolinguistic programing strategies). Comments on the author's participation in the…

  17. The Journal of Mathematical Chemistry: A Bibliometric Profile

    OpenAIRE

    Willett, P.; Restrepo, G.

    2017-01-01

    This paper describes the bibliometric characteristics of 2,398 articles published in the Journal of Mathematical Chemistry in the period 1987-2015. These articles have been analysed using data from the Web of Science Core Collection and demonstrate the contribution of the journal not only to mathematical chemistry but also to science more generally.

  18. Impact of Theoretical Chemistry on Chemical and Biological Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 4. Impact of Theoretical Chemistry on Chemical and Biological Sciences: Chemistry Nobel Prize – 2013. Saraswathi Vishveshwara. General Article Volume 19 Issue 4 April 2014 pp 347-367 ...

  19. Kinetics of Carbaryl Hydrolysis: An Undergraduate Environmental Chemistry Laboratory

    Science.gov (United States)

    Hawker, Darryl

    2015-01-01

    Kinetics is an important part of undergraduate environmental chemistry curricula and relevant laboratory exercises are helpful in assisting students to grasp concepts. Such exercises are also useful in general chemistry courses because students can see relevance to real-world issues. The laboratory exercise described here involves determination of…

  20. Effect of a Virtual Chemistry Laboratory on Students' Achievement

    Science.gov (United States)

    Tatli, Zeynep; Ayas, Alipasa

    2013-01-01

    It is well known that laboratory applications are of significant importance in chemistry education. However, laboratory applications have generally been neglected in recent educational environments for a variety of reasons. In order to address this gap, this study examined the effect of a virtual chemistry laboratory (VCL) on student achievement…

  1. Avaliação do conhecimento sobre periodicidade química em uma turma de química geral do ensino a distância Assessment of knowledge on chemical periodicity in a distance-learning general chemistry class

    Directory of Open Access Journals (Sweden)

    Miguel de Araújo Medeiros

    2013-01-01

    Full Text Available This work describes the software Quiptabela, suggests a teaching activity, and analyses responses of general chemistry students from the Biological Sciences distance course at the Federal University of Tocantins. The software was described according to its educational potential, featuring the creation of dozens of charts or tables correlating physicochemical properties of the elements, being Brazilian, and free distribution. The teaching activities suggested analyzed students' ability to create and analyze tables and charts correlating the properties of chemical elements. Some 41% of students tested could define the term "periodic", but failed to use the concept to explain and differentiate changes in mass or atomic radius with the atomic number of elements.

  2. Asymmetric translation between multiple representations in chemistry

    Science.gov (United States)

    Lin, Yulan I.; Son, Ji Y.; Rudd, James A., II

    2016-03-01

    Experts are more proficient in manipulating and translating between multiple representations (MRs) of a given concept than novices. Studies have shown that instruction using MR can increase student understanding of MR, and one model for MR instruction in chemistry is the chemistry triplet proposed by Johnstone. Concreteness fading theory suggests that presenting concrete representations before abstract representations can increase the effectiveness of MR instruction; however, little work has been conducted on varying the order of different representations during instruction and the role of concreteness in assessment. In this study, we investigated the application of concreteness fading to MR instruction and assessment in teaching chemistry. In two experiments, undergraduate students in either introductory psychology courses or general chemistry courses were given MR instruction on phase changes using different orders of presentation and MR assessment questions based on the representations in the chemistry triplet. Our findings indicate that the order of presentation based on levels of concreteness in MR chemistry instruction is less important than implementation of comprehensive MR assessments. Even after MR instruction, students display an asymmetric understanding of the chemical phenomenon on the MR assessments. Greater emphasis on MR assessments may be an important component in MR instruction that effectively moves novices toward more expert MR understanding.

  3. Delay-line cables for the fast bumpers in the PS.

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    For 'continuous transfer' to the SPS, the beam accelerated in the PS is shaved off over several turns, so as to form a continuous sequence of bunches several times the length of the PS circumference. Fast bumpers, powered in a 'staircase' way, displace the PS beam stepwise towards the ejection septum. Each step lasts 2.1 microsec and the cable drums in this picture contain some of the bumper delay-lines of altogether 10 km.

  4. A DiPS+ case study: a self-healing RADIUS server

    OpenAIRE

    Michiels, Sam; Desmet, Lieven; Verbaeten, Pierre

    2004-01-01

    This report shows performance results of a RADIUS implementation using the DiPS+ software architecture. In addition it compares this implementation with a commercially available RADIUS implementation, and shows that the DiPS+ architecture differentiates between user types and request types. In fact, the DiPS+ prototype prioritizes incoming traffic based on application-specifc preferences, and allocates the available processing resources to the highest priority requests.

  5. Microfabricated device for co-culture of sympathetic neuron and iPS-derived cardiomyocytes.

    Science.gov (United States)

    Takeuchi, Akimasa; Shimba, Kenta; Takayama, Yuzo; Kotani, Kiyoshi; Lee, Jong-Kook; Noshiro, Makoto; Jimbo, Yasuhiko

    2013-01-01

    Induced pluripotent stem (iPS) cell-derived cardiomyocytes (iPS-CMs) has been expected as a cell source for therapy of serious heart failure. However, it is unclear whether the function of iPS-CMs is modulated by the host sympathetic nervous system. Here we developed a device for co-culture of sympathetic neurons and iPS-CMs using microfabrication technique. The device consisted of a culture chamber and a microelectrode-array (MEA) substrate. The superior cervical ganglion (SCG) neurons were co-cultured with iPS-CMs in a microfabricated device, which had multiple compartments. Several days after seeding, synapses were formed between SCG neurons and iPS-CMs, as confirmed by immunostaining. Spontaneous electrical activities of the SCG neurons and the iPS-CMs were observed from the electrode of the MEA substrate. The beat rate of iPS-CMs increased after electrical stimulation of the co-cultured SCG neurons. Such changes in the beat rate were prevented in the presence of propranolol, a β-adrenoreceptor antagonist. These results suggest that the microfabricated device will be utilized for studying the functional modulation of iPS-CMs by connected sympathetic neurons.

  6. Facile Synthesis of Mono-Dispersed Polystyrene (PS/Ag Composite Microspheres via Modified Chemical Reduction

    Directory of Open Access Journals (Sweden)

    Wen Zhu

    2013-12-01

    Full Text Available A modified method based on in situ chemical reduction was developed to prepare mono-dispersed polystyrene/silver (PS/Ag composite microspheres. In this approach; mono-dispersed PS microspheres were synthesized through dispersion polymerization using poly-vinylpyrrolidone (PVP as a dispersant at first. Then, poly-dopamine (PDA was fabricated to functionally modify the surfaces of PS microspheres. With the addition of [Ag(NH32]+ to the PS dispersion, [Ag(NH32]+ complex ions were absorbed and reduced to silver nanoparticles on the surfaces of PS-PDA microspheres to form PS/Ag composite microspheres. PVP acted both as a solvent of the metallic precursor and as a reducing agent. PDA also acted both as a chemical protocol to immobilize the silver nanoparticles at the PS surface and as a reducing agent. Therefore, no additional reducing agents were needed. The resulting composite microspheres were characterized by TEM, field emission scanning electron microscopy (FESEM, energy-dispersive X-ray spectroscopy (EDS, XRD, UV-Vis and surface-enhanced Raman spectroscopy (SERS. The results showed that Ag nanoparticles (NPs were homogeneously immobilized onto the PS microspheres’ surface in the presence of PDA and PVP. PS/Ag composite microspheres were well formed with a uniform and compact shell layer and were adjustable in terms of their optical property.

  7. Lehtmets : psühhiaatria ei ole piisavalt atraktiivne / Andres Lehtmets ; interv. Marika Kusnets

    Index Scriptorium Estoniae

    Lehtmets, Andres

    2004-01-01

    Vestlus Eesti Psühhiaatrite Seltsi aseesimehega rahva vaimsest tervisest. Samas ka sotsiaalministeeriumi rahvatervise osakonna peaspetsialisti Helja Eomoisi kommentaar: Mida teeb ministeerium rahva vaimse tervise parandamiseks?

  8. Chemistry with a Peel.

    Science.gov (United States)

    Borer, Londa; Larsen, Eric

    1997-01-01

    Presents experiments that introduce natural product chemistry into high school classrooms. In the laboratory activities, students isolate and analyze the oil in orange peels. Students also perform a steam distillation and learn about terpenes. (DDR)

  9. Indicators: Soil Chemistry

    Science.gov (United States)

    The chemical makeup of the soil can provide information on wetland condition, wetland water quality and services being provided by the wetland ecosystem. Analyzing soil chemistry reveals if the soil is contaminated with a toxic chemical or heavy metal.

  10. Microfluidics in inorganic chemistry.

    Science.gov (United States)

    Abou-Hassan, Ali; Sandre, Olivier; Cabuil, Valérie

    2010-08-23

    The application of microfluidics in chemistry has gained significant importance in the recent years. Miniaturized chemistry platforms provide controlled fluid transport, rapid chemical reactions, and cost-saving advantages over conventional reactors. The advantages of microfluidics have been clearly established in the field of analytical and bioanalytical sciences and in the field of organic synthesis. It is less true in the field of inorganic chemistry and materials science; however in inorganic chemistry it has mostly been used for the separation and selective extraction of metal ions. Microfluidics has been used in materials science mainly for the improvement of nanoparticle synthesis, namely metal, metal oxide, and semiconductor nanoparticles. Microfluidic devices can also be used for the formulation of more advanced and sophisticated inorganic materials or hybrids.

  11. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 7. Electrostatics in Chemistry - Molecular Electrostatic Potential: Visualization and Topography. Shridhar R Gadre Pravin K Bhadane. Series Article Volume 4 Issue 7 July 1999 pp 14-23 ...

  12. Handbook for High School Chemistry Teachers.

    Science.gov (United States)

    Bedenbaugh, John H., Ed.; Bedenbaugh, Angela O., Ed.

    This handbook is based on a list of essential topics that should be mastered by the student who subsequently plans to pursue college chemistry. Chapters include: (1) "Introduction" (describing a position paper and the background of the handbook); (2) "Essential General Topics and Objectives"; (3) "Testing Students" (providing sample tests and…

  13. An Epitome of K. Venkataraman's Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 12. An Epitome of K. Venkataraman's Chemistry. Gopalpur Nagendrappa. General Article Volume 9 Issue 12 ... Keywords. Flavones; Baker-Venkataraman transformation; azo and alizarine dyes; Raney nickel-hydrogenation; naphthols.

  14. Solid Acid Catalysts in Green Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 10. Solid Acid Catalysts in Green Chemistry - Some Practical Examples. Leena Rao. General Article Volume 12 Issue 10 October 2007 pp 30-36. Fulltext. Click here to view fulltext PDF. Permanent link:

  15. Solid Acid Catalysts in Green Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 8. Solid Acid Catalysts in Green Chemistry - Emerging Eco-Friendly Practices in Chemical Industry. Leena Rao. General Article Volume 12 Issue 8 August 2007 pp 65-75 ...

  16. One Hundred Years of Peptide Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 7. One Hundred Years of Peptide Chemistry. V V Suresh Babu. General Article Volume 16 Issue 7 July 2011 pp 640-647. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/016/07/0640-0647 ...

  17. One Hundred Years of Peptide Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 10. One Hundred Years of Peptide Chemistry. V V Suresh Babu. General Article Volume 6 Issue 10 October 2001 pp 68-75. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/006/10/0068-0075 ...

  18. Applications of supramolecular chemistry

    CERN Document Server

    Schneider, Hans-Jörg

    2012-01-01

    ""The time is ripe for the present volume, which gathers thorough presentations of the numerous actually realized or potentially accessible applications of supramolecular chemistry by a number of the leading figures in the field. The variety of topics covered is witness to the diversity of the approaches and the areas of implementation…a broad and timely panorama of the field assembling an eminent roster of contributors.""-Jean-Marie Lehn, 1987 Noble Prize Winner in Chemistry

  19. Fundamentals of quantum chemistry

    CERN Document Server

    House, J E

    2004-01-01

    An introduction to the principles of quantum mechanics needed in physical chemistry. Mathematical tools are presented and developed as needed and only basic calculus, chemistry, and physics is assumed. Applications include atomic and molecular structure, spectroscopy, alpha decay, tunneling, and superconductivity. New edition includes sections on perturbation theory, orbital symmetry of diatomic molecules, the Huckel MO method and Woodward/Hoffman rules as well as a new chapter on SCF and Hartree-Fock methods. * This revised text clearly presents basic q

  20. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation