Collagen sheet dressings for cutaneous lesions of toxic epidermal necrolysis

Directory of Open Access Journals (Sweden)

S Bhattacharya

2011-01-01

Full Text Available Toxic epidermal necrolysis (TEN is associated with a significant mortality of 30-50% and long-term sequelae. Treatment includes early admission to a burn unit, where management with precise fluid, electrolyte, protein, and energy supplementation, moderate mechanical ventilation, and expert wound care can be provided. Specific treatment with immunosuppressive drugs or immunoglobulins did not show an improved outcome in most studies and remains controversial. We have treated the cutaneous lesions of seven patients of TEN with collagen sheet dressings and have found a significant reduction in morbidity. The sheets are a one-time dressing, easy to apply and they reduce fluid loss, prevent infection, reduce pain, avoid repeated dressings and gradually peal off as the underlying lesions heal.

Effects of zinc supplementation on parent and teacher behaviour rating scores in low socioeconomic level Turkish primary school children.

Science.gov (United States)

Uçkardeş, Yasemin; Ozmert, Elif N; Unal, Fatih; Yurdakök, Kadriye

2009-04-01

To determine the effect of zinc supplementation on behaviour in low-income school aged children. Double-blind randomized, placebo controlled trial. Low-income district primary school in Turkey. Third grade students in the school. Among 252 students, 226 participated and 218 completed the study. Children in each class were randomized either to the study group to receive 15 mg/day elemental zinc syrup or to placebo group to receive the syrup without zinc for 10 weeks. The change in Conner's Rating Scales for Teachers and Parents scores after supplementation. The mean Conner's Rating Scale for Parents scores on attention deficit, hyperactivity, oppositional behaviour and conduct disorder decreased significantly in the study and placebo groups after supplementation (p children with clinically significant parent ratings on attention deficit (p = 0.01) and hyperactivity (p = 0.004) decreased in the study group while prevalence of oppositional behaviour (p = 0.007) decreased in the placebo group. In children of mothers with low education all mean Parents' scores decreased significantly (p children with clinically significant scores for attention deficit, hyperactivity and oppositional behaviour decreased only in the study group (p children with clinically significant scores for attention deficit and hyperactivity. The affect on behaviour was more evident in the children of low educated mothers.

Evolutions and Trends in Presenting. The Balance Sheet as a Financial Position Picture of an Entity

Directory of Open Access Journals (Sweden)

Ecaterina Necsulescu

2011-08-01

Full Text Available In this article we proposed to achieve a synthesis of the key moments in the evolution of the concept of balance, of the theories formulated over time, of the presentation forms of the balance sheet, a taxonomy of balance sheets, supplemented by a breakdown of the concept of financial position and of the structures related to the assessment of the financial position. In other words, we will consider a gradual presentation of the concept of balance sheet over time and a presentation of the balance as the main tool for highlighting the patrimonial situation, of the assets of enterprise owners and of the picture on the financial position of an economic entity.

Teacher's Guide to "Artes Latinae".

Science.gov (United States)

Masciantonio, Rudolph; And Others

The purpose of this guide is to assist teachers in the classroom utilization of "Artes Latinae", the Encyclopaedia Britannica Latin instructional system. This guide is intended as a supplement to the publisher's teacher's manual and presupposes familiarity with it. Stress has been placed on the early units of the textbook, since the inexperienced…

Locus of Control as It Relates to the Teaching Style of Elementary Teachers

Science.gov (United States)

Ture, Abidemi

2013-01-01

This research explored the relationship between elementary teachers' locus of control and teaching style. This research observed elementary teachers in their classrooms coupled with data gathered from information sheets, surveys, and interviews to determine if a relationship exists between the locus of control of the elementary teachers and…

[Recommendations on vitamin D and calcium supplements for adults in Spain].

Science.gov (United States)

Rigueira García, Ana Isabel

2012-10-01

Calcium supplements and vitamin D are involved in current debates of health, as cardiovascular safety of calcium, and correction of vitamin levels. The aim is to review the possibilities of making better use of supplements marketed in Spain, depending on their availability, information and related epidemiology. Analysis of comercial offer and available information about pharmacological aspects of Spanish medicinal supplements in data-sheets (39), guides and reports current institutional and professional, with additional search of this information and epidemiological data related Spanish in Cochrane Database of Systematic Reviews ®, PubMed ® (tool "Clinical Queries"), Dialnet database and hand search of Spanish journals directly related. There is no uniformity in terms of indication, expression of content, dosages, precautions and safety in data sheets or technical reports. The literature search found more recent publications volume for vitamin D than calcium, No evidence was found to establish appropriate dosing regimens indisputable or universal, or cholecalciferol bioavailability tests with aqueous vehiculización. In Spain nutritional situation is found generally suitable for the calcium but a status mostly unsuitable for vitamin D with several references for insufficiency and vitamin deficiency in adults. Corrective treatments primarily affect calcium supplements. There is an ample supply of calcium and vitamin D in Spain, whose drug design should rethink because don't respond to the needs identified or correction possibilities currently recommended. It should also improve and update their information, with particular interest in health status related to hypovitaminosis D.

Web-based Tools for Educators: Outreach Activities of the Polar Radar for Ice Sheet Measurements (PRISM) Project

Science.gov (United States)

Braaten, D. A.; Holvoet, J. F.; Gogineni, S.

2003-12-01

The Radar Systems and Remote Sensing Laboratory at the University of Kansas (KU) has implemented extensive outreach activities focusing on Polar Regions as part of the Polar Radar for Ice Sheet Measurements (PRISM) project. The PRISM project is developing advanced intelligent remote sensing technology that involves radar systems, an autonomous rover, and communications systems to measure detailed ice sheet characteristics, and to determine bed conditions (frozen or wet) below active ice sheets in both Greenland and Antarctica. These measurements will provide a better understanding of the response of polar ice sheets to global climate change and the resulting impact the ice sheets will have on sea level rise. Many of the research and technological development aspects of the PRISM project, such as robotics, radar systems, climate change and exploration of harsh environments, can kindle an excitement and interest in students about science and technology. These topics form the core of our K-12 education and training outreach initiatives, which are designed to capture the imagination of young students, and prompt them to consider an educational path that will lead them to scientific or engineering careers. The K-12 PRISM outreach initiatives are being developed and implemented in a collaboration with the Advanced Learning Technology Program (ALTec) of the High Plains Regional Technology in Education Consortium (HPR*TEC). ALTec is associated with the KU School of Education, and is a well-established educational research center that develops and hosts web tools to enable teachers nationwide to network, collaborate, and share resources with other teachers. An example of an innovative and successful web interface developed by ALTec is called TrackStar. Teachers can use TrackStar over the Web to develop interactive, resource-based lessons (called tracks) on-line for their students. Once developed, tracks are added to the TrackStar database and can be accessed and modified

Decontamination sheet

International Nuclear Information System (INIS)

Hirose, Emiko; Kanesaki, Ken.

1995-01-01

The decontamination sheet of the present invention is formed by applying an adhesive on one surface of a polymer sheet and releasably appending a plurality of curing sheets. In addition, perforated lines are formed on the sheet, and a decontaminating agent is incorporated in the adhesive. This can reduce the number of curing operation steps when a plurality steps of operations for radiation decontamination equipments are performed, and further, the amount of wastes of the cured sheets, and operator's exposure are reduced, as well as an efficiency of the curing operation can be improved, and propagation of contamination can be prevented. (T.M.)

Teacher Perceptions of an Online Tutoring Program for Elementary Mathematics

Science.gov (United States)

Whetstone, Patti; Clark, Amy; Flake, Mari Wheeler

2014-01-01

This study explores elementary teacher perceptions related to the implementation of an online tutoring program. Teachers were surveyed regarding factors that affected use of the online tutoring program as a supplement to mathematics instruction. Results indicated that teachers overwhelmingly reported positive views of the training and support…

Field-Based Teacher Research: How Teachers and Scientists Working Together Answers Questions about Turtle Nesting Ecology while Enhancing Teachers' Inquiry Skills

Science.gov (United States)

Winters, J. M.; Jungblut, D.; Catena, A. N.; Rubenstein, D. I.

2013-12-01

Providing rigorous academic supplement to a professional development program for teachers, QUEST is a fusion of Drexel University's environmental science research department with Princeton University's Program in Teacher Preparation. Completed in the summers of 2012 (in partnership with Earthwatch) and 2013 in Barnegat Bay, New Jersey, QUEST's terrapin field research program enhances K-12 teachers' ecological knowledge, develops inquiry-based thinking in the classroom, and builds citizen science engagement. With a focus on quality question development and data analysis to answer questions, teachers are coached in developing, implementing, and presenting independent research projects on diamondback terrapin nesting ecology. As a result, teachers participating in QUEST's week long program bring a realistic example of science in action into their classrooms, helping to develop their own students' critical thinking skills. For teachers, this program provides training towards educating students on how to do real and imaginative science - subsequently sending students to university better prepared to engage in their own independent research. An essential component of the collaboration through QUEST, in addition to the teacher's experience during and after the summer institute, is the research data collected which supplements that of the Principal Investigator. In 2012, by documenting terrapin nest site predators, teachers gained valuable scientific experience, while Drexel acquired important ecological data which would have not been able to be collected otherwise. In 2013, teachers helped answer important questions about terrapin nesting success post Superstorm Sandy. In fact, the 2013 QUEST teachers are the first to visualize the frighteningly increased erosion of a primary terrapin nesting site due to Sandy; showing how most terrapin nests now lie in the bay, instead of safe on shore. Teachers comment that interacting with scientists in the field, and contributing to

Basics of Desktop Publishing. Teacher Edition.

Science.gov (United States)

Beeby, Ellen

This color-coded teacher's guide contains curriculum materials designed to give students an awareness of various desktop publishing techniques before they determine their computer hardware and software needs. The guide contains six units, each of which includes some or all of the following basic components: objective sheet, suggested activities…

The Potato People in "School Daze": Presented by Theatre Beyond Words. Cue Sheet for Students.

Science.gov (United States)

Briley, Rachel

This performance guide is designed for teachers to use with students before and after a performance of the Potato People in "School Daze." The guide, called a "Cuesheet," contains seven pages of reproducible activity sheets for use in class with activities and discussion questions on the following topics: (1) Meet the…

Fuel cell technology for classroom instruction. Basic principles, experiments, work sheets. 2. ed.

Energy Technology Data Exchange (ETDEWEB)

Voigt, Cornelia; Hoeller, Stefan; Kueter, Uwe

2009-07-01

This book provides a clear introduction and overview to fuel cell technology and its associated subject areas. Examples of experiments using solar cells, electrolysis and fuel cells convey the knowledge for forthcoming tests in an understandable manner. The preparation of classroom experiments is made considerably easier for the teacher thanks to the experiment work sheets. These contain the necessary information concerning the material, set-up and execution of the experiment, and questions for evaluation purposes. Online-Shop The training documents and student work sheets combine the basic knowledge, questions and answers, and are ideal for copying. A comprehensive glossary at the end of the book explains all the important technical terms. (orig.)

Understanding the Educational Experiences of Science Teachers in a Five-Year Teacher Education Program: A Phenomenological Study

Science.gov (United States)

Srivastava, Nitin

This qualitative study provides an overview of educational experiences of six in-service and three pre-service secondary science teachers in the Benedum Collaborative Five-Year Teacher Education Program at a land-grant university. The researcher interviewed secondary science teachers on the experiences they found meaningful in various program components that influenced their teacher identity, beliefs about science pedagogy, and their sense of preparedness for teaching. Document analysis of teachers' journals and lesson plans supplemented the qualitative data in addition to the researcher's role and knowledge as an outsider (non-Benedum graduate) and insider (facilitator and instructor in the technology integration based classes for one year) of the Benedum Collaborative Five-Year Teacher Education Program. Findings also supported the Holmes (1986) and Goodlad (1990) views for extended field experiences and "collaborative culture" in teacher education for well-prepared teachers.

Summer Research Fellowships for Students and Teachers - 2005

Indian Academy of Sciences (India)

Fellows willing to accept students/teachers for work on joint short-term projects are included as a supplement in the November 2004 issue of Resonance - journal of science education. This information is also available in the Academy website. Proposals are invited from interested students and teachers for these Fellowships ...

9/11 and the War on Terror in Curricula and in State Standards Documents. CIRCLE Fact Sheet

Science.gov (United States)

Stoddard, Jeremy; Hess, Diana

2011-01-01

This Fact Sheet reports findings from an ongoing study of the representation of 9/11 and terrorism in curricula, textbooks, and state standards documents. The study was conducted in three stages. The first two stages focused on how supplemental curricula and best-selling social studies textbooks published between 2002-2010 present the events of…

High school athletes and nutritional supplements: a study of knowledge and use.

Science.gov (United States)

Massad, S J; Shier, N W; Koceja, D M; Ellis, N T

1995-09-01

Factors influencing nutritional supplement use by high school students were assessed. Comparisons were made between various groups of sports participants and non-sports participants. The Nutritional Supplement Use and Knowledge Scale was administered to 509 students. Mean supplement use score was 10.87 (SEM = 0.50, range 0-57). Mean knowledge score was 13.56 (SEM = 0.16, range 1-21). Significant relationships (p knowledge with use, and supplement use with gender. ANOVA found significant differences between supplement use by gender (p knowledge scores by sports category (p knowledge, supplement use, and subscores for protein, vitamins/minerals, knowledge, supplement use, and subscores for protein, vitamins/minerals, and carbohydrates were best discriminators of sport group membership. Greater knowledge about supplements was associated with less use; hence, education about supplements can be a deterrent to use. This study may help coaches, athletic trainers, athletic directors, teachers, physicians, and parents identify nutritional misconceptions held by adolescents.

Dense sheet Z-pinches

International Nuclear Information System (INIS)

Tetsu, Miyamoto

1999-01-01

The steady state and quasi-steady processes of infinite- and finite-width sheet z-pinches are studied. The relations corresponding to the Bennett relation and Pease-Braginskii current of cylindrical fiber z-pinches depend on a geometrical factor in the sheet z-pinches. The finite-width sheet z-pinch is approximated by a segment of infinite-width sheet z-pinch, if it is wide enough, and corresponds to a number of (width/thickness) times fiber z-pinch plasmas of the diameter that equals the sheet thickness. If the sheet current equals this number times the fiber current, the plasma created in the sheet z-pinches is as dense as in the fiber z-pinches. The total energy of plasma and magnetic field per unit mass is approximately equal in both pinches. Quasi-static transient processes are different in several aspects from the fiber z-pinch. No radiation collapse occurs in the sheet z-pinch. The stability is improved in the sheet z-pinches. The fusion criterions and the experimental arrangements to produce the sheet z-pinches are also discussed. (author)

Dietary docosahexaenoic acid supplementation in children with autism.

Science.gov (United States)

Voigt, Robert G; Mellon, Michael W; Katusic, Slavica K; Weaver, Amy L; Matern, Dietrich; Mellon, Bryan; Jensen, Craig L; Barbaresi, William J

2014-06-01

The aim of the study was to determine whether docosahexaenoic acid (DHA) supplementation improves the behavior of children with autism. A group of 3- to 10-year-old children with autism were randomized in a double-blind fashion to receive a supplement containing 200 mg of DHA or a placebo for 6 months. The parents and the investigator completed the Clinical Global Impressions-Improvement scale to rate changes in core symptoms of autism after 3 and 6 months. The parents completed the Child Development Inventory and the Aberrant Behavior Checklist, and both parents and teachers completed the Behavior Assessment Scale for Children (BASC) at enrollment and after 6 months. A total of 48 children (40 [83%] boys, mean age [standard deviation] 6.1 [2.0] years) were enrolled; 24 received DHA and 24 placebo. Despite a median 431% increase in total plasma DHA levels after 6 months, the DHA group was not rated as improved in core symptoms of autism compared to the placebo group on the CGI-I. Based on the analysis of covariance models adjusted for the baseline rating scores, parents (but not teachers) provided a higher average rating of social skills on the BASC for the children in the placebo group compared to the DHA group (P = 0.04), and teachers (but not parents) provided a higher average rating of functional communication on the BASC for the children in the DHA group compared to the placebo group (P = 0.02). Dietary DHA supplementation of 200 mg/day for 6 months does not improve the core symptoms of autism. Our results may have been limited by inadequate sample size.

TEDS-M 2008 User Guide for the International Database. Supplement 1: International Version of the TEDS-M Questionnaires

Science.gov (United States)

Brese, Falk, Ed.

2012-01-01

The Teacher Education Study in Mathematics (TEDS-M) International Database includes data for all questionnaires administered as part of the TEDS-M study. These consisted of questionnaires administered to future teachers, educators, and institutions with teacher preparation programs. This supplement contains the international version of the TEDS-M…

Implementing the adapted physical education E-learning program into physical education teacher education program.

Science.gov (United States)

Kwon, Eun Hye; Block, Martin E

2017-10-01

According to the Ministry of Education Korea (2014), the approximately 70.4% of all students with disabilities are included in general schools in Korea. However, studies show that Korean GPE teachers do not feel comforatble or prepared to include students with disabilities (Oh & Lee, 1999; Roh, 2002; Roh & Oh, 2005). The purpose of this study was to explore whether an APE e-learning supplement would have an impact on the level of self-efficacy and content knowledge of pre-service teachers related to including students with intellectual disabilities. An APE supplement was developed based on the Instructional Design Model (Dick, Carey, & Carey, 2005) to provide three sources of self-efficacy, mastery experience, vicarious experience, and social persuasions. Three groups of pre-service teachers (N=75) took the same content supplement with different delivery system, E-learning group (n=25) with online, traditional group (n=25) with printed handout, and control group (n=25) without supplement. Two instruments, the Physical Educators' Situation-Specific Self-efficacy and Inclusion Student with Disabilities in Physical Education (SE-PETE-D) and the content knowledge test, were given to all participants twice (i.e., pretest and posttest). A 3×2 mixed effect ANOVA revealed that pre-service teachers' perceived self-efficacy (p=0.023) improved after taking the e-learning supplement. However, there was no significant difference in the level of content knowledge (p=0.248) between the learning group and tranditional group. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of alternative flow sheets for the hybrid chlorine cycle

Energy Technology Data Exchange (ETDEWEB)

Gooding, Charles H. [Department of Chemical and Biomolecular Engineering, 209 Earle Hall, Clemson University, Clemson, SC 29634-0909 (United States)

2009-05-15

This paper reports the results of the most complete conceptual study conducted to date on hydrogen production using the hybrid chlorine cycle. Three alternative process flow sheets were developed, each capable of producing hydrogen at 35 C (308 K) and 21 bar. The alternative approaches differ primarily in the way HCl is isolated and converted to hydrogen and chlorine gases. Aspen Plus trademark simulation software was used to model the unit processes, supplemented where necessary by custom Excel spreadsheets. Major equipment was sized for a 200-million kg/yr plant; feasible materials of construction were identified; fixed capital investments and variable costs were estimated. Estimated net thermal efficiencies of the flow sheets range from 30% to 36%, based on the lower heating value of the hydrogen produced. With electrical power valued at $0.05/kWh, the cost of hydrogen produced by the hybrid chlorine cycle would be at least $3/kg. These results indicate that direct electrolysis of water is a more attractive way to produce hydrogen than any presently conceived version of the hybrid chlorine cycle. (author)

Are we reaching the target audience? Evaluation of a fish fact sheet.

Science.gov (United States)

Burger, J; Waishwell, L

2001-09-28

According to the US Environmental Protection Agency, over 16% of freshwater lakes and 7% of the rivers are under some sort of fish consumption advisory because of the presence of toxic chemicals. There is considerable interest in the issuing of information, advisories, and fact sheets concerning the consumption of wild-caught fish from contaminated waters, and in the actual consumption patterns of subsistence and recreational anglers. Despite the large number of consumption advisories issued by state agencies, there is little information on how these advisories, or other forms of risk communication, are perceived by target audiences, notably fishermen and women of child-bearing age. The states of South Carolina and Georgia issue consumption advisories for fish from the Savannah River, among other sites. To gain a greater insight into the perception of anglers about a supplemental fish fact sheet jointly developed by South Carolina, Georgia, federal agencies, and the Consortium for Risk Evaluation with Stakeholder Participation, we interviewed fisherman along the Savannah River. The objectives were to determine: (1) whether they had previously read the Fish Fact Sheet or had heard about the consumption advisories; (2) what major message they obtained from the sheet; (3) who they felt the fact sheet was aimed at, and who should get the Fish Fact Sheet; (4) who should be concerned about health risks from consuming the fish; and (5) the best method of disseminating such information. We interviewed 92 fishermen (37% black, 62% white) during the fishing season of 1999. Half had heard some information about consumption advisories, mainly from the media (64%). The study concluded that there were no ethnic differences in whether they had heard about the advisories, understood the major message of the fact sheet, felt they could reduce their risk from consuming the fish, or felt that it made a difference which agency issued the fact sheet. There were significant ethnic

Long-chain n-3 PUFA supplementation decreases physical activity during class time in iron-deficient South African school children.

Science.gov (United States)

Smuts, Cornelius M; Greeff, Jani; Kvalsvig, Jane; Zimmermann, Michael B; Baumgartner, Jeannine

2015-01-28

Both Fe deficiency and poor n-3 fatty acid status have been associated with behavioural changes in children. In the present study, we investigated the effects of Fe and DHA+EPA supplementation, alone or in combination, on physical activity during school days and on teacher-rated behaviour in healthy Fe-deficient school children. In a 2 × 2 factorial design, children (n 98, 6-11 years) were randomly assigned to receive (1) Fe (50 mg) plus DHA (420 mg)+EPA (80 mg), (2) Fe plus placebo, (3) placebo plus DHA+EPA or (4) placebo plus placebo as oral supplements (4 d/week) for 8.5 months. Physical activity was measured during four school days at baseline and endpoint using accelerometers, and data were stratified into morning class time (08.00-10.29 hours), break time (10.30-11.00 hours) and after-break class time (11.01-12.00 hours) for analysis. Classroom behaviour was assessed at endpoint using Conners' Teacher Rating Scales. DHA+EPA supplementation decreased physical activity counts during morning class time, increased sedentary physical activity, and decreased light- and moderate-intensity physical activities. Consistently, DHA+EPA supplementation increased sedentary physical activity and decreased light-intensity physical activity during after-break class time. Even though there were no treatment effects found on teacher-rated behaviour, lower physical activity during morning class time was associated with lower levels of teacher-rated hyperactivity and oppositional behaviour at endpoint. Despite a positive association between Fe status and physical activity during break time at baseline, Fe supplementation did not affect physical activity during break time and class time. Our findings suggest that DHA+EPA supplementation may decrease physical activity levels during class time, and further indicate that accelerometry might be a useful tool to assess classroom behaviour in healthy children.

Relation between current sheets and vortex sheets in stationary incompressible MHD

Directory of Open Access Journals (Sweden)

D. H. Nickeler

2012-03-01

Full Text Available Magnetohydrodynamic configurations with strong localized current concentrations and vortices play an important role in the dissipation of energy in space and astrophysical plasma. Within this work we investigate the relation between current sheets and vortex sheets in incompressible, stationary equilibria. For this approach it is helpful that the similar mathematical structure of magnetohydrostatics and stationary incompressible hydrodynamics allows us to transform static equilibria into stationary ones. The main control function for such a transformation is the profile of the Alfvén-Mach number MA, which is always constant along magnetic field lines, but can change from one field line to another. In the case of a global constant MA, vortices and electric current concentrations are parallel. More interesting is the nonlinear case, where MA varies perpendicular to the field lines. This is a typical situation at boundary layers like the magnetopause, heliopause, the solar wind flowing around helmet streamers and at the boundary of solar coronal holes. The corresponding current and vortex sheets show in some cases also an alignment, but not in every case. For special density distributions in 2-D, it is possible to have current but no vortex sheets. In 2-D, vortex sheets of field aligned-flows can also exist without strong current sheets, taking the limit of small Alfvén Mach numbers into account. The current sheet can vanish if the Alfvén Mach number is (almost constant and the density gradient is large across some boundary layer. It should be emphasized that the used theory is not only valid for small Alfvén Mach numbers MA MA ≲ 1. Connection to other theoretical approaches and observations and physical effects in space plasmas are presented. Differences in the various aspects of theoretical investigations of current sheets and vortex sheets are given.

An ice sheet model validation framework for the Greenland ice sheet

Science.gov (United States)

Price, Stephen F.; Hoffman, Matthew J.; Bonin, Jennifer A.; Howat, Ian M.; Neumann, Thomas; Saba, Jack; Tezaur, Irina; Guerber, Jeffrey; Chambers, Don P.; Evans, Katherine J.; Kennedy, Joseph H.; Lenaerts, Jan; Lipscomb, William H.; Perego, Mauro; Salinger, Andrew G.; Tuminaro, Raymond S.; van den Broeke, Michiel R.; Nowicki, Sophie M. J.

2017-01-01

We propose a new ice sheet model validation framework - the Cryospheric Model Comparison Tool (CmCt) - that takes advantage of ice sheet altimetry and gravimetry observations collected over the past several decades and is applied here to modeling of the Greenland ice sheet. We use realistic simulations performed with the Community Ice Sheet Model (CISM) along with two idealized, non-dynamic models to demonstrate the framework and its use. Dynamic simulations with CISM are forced from 1991 to 2013, using combinations of reanalysis-based surface mass balance and observations of outlet glacier flux change. We propose and demonstrate qualitative and quantitative metrics for use in evaluating the different model simulations against the observations. We find that the altimetry observations used here are largely ambiguous in terms of their ability to distinguish one simulation from another. Based on basin-scale and whole-ice-sheet-scale metrics, we find that simulations using both idealized conceptual models and dynamic, numerical models provide an equally reasonable representation of the ice sheet surface (mean elevation differences of framework demonstrates that our proposed metrics can distinguish relatively better from relatively worse simulations and that dynamic ice sheet models, when appropriately initialized and forced with the right boundary conditions, demonstrate a predictive skill with respect to observed dynamic changes that have occurred on Greenland over the past few decades. An extensible design will allow for continued use of the CmCt as future altimetry, gravimetry, and other remotely sensed data become available for use in ice sheet model validation.

Bryological exploration: field-trip based learning to develop competencies of science teacher candidate

Science.gov (United States)

Wisanti; Astriani, D.

2018-04-01

The purpose of this study was analyze the competencies of science teacher candidate after the bryological exploration. The intended competence of science teacher candidate was the ability to apply the concept and science ability to explore plant diversity that could be found around the environment.This field trip was conducted by exploring liverworts, hornworts, and mosses as well. This descriptive research was conducted during March until April 2017 at Universitas Negeri Surabaya (UNESA) and Sumber Brantas Arboretum in Malang, as the location of exploration. The subjects of this study were 76 candidate of teachers from science educations department, which is divided into three classes. The competences observed on this study were describing, identifying, collecting specimens, furthermore. The research instruments were observation sheets, product assessment sheets, and response questionnaire. The data were analyzed descriptive-quantitatively, in percentage and then categorized. The results of this study indicated that: the describing skill was categorized as ‘good’ identifying skill and collecting bryophytes was categorized as ‘very good’ and communicating skills was categorized ‘good’. In addition, the teacher candidates gave a very good response to field-trip-based learning. It can be concluded that the bryological exploration can develop the competences of science teacher candidates of Science Education Department of UNESA.

"Sundiata, Lion King of Mali." Adapted by Kim Hines, Featuring Griot Alhaji Papa Susso, Cue Sheet for Students.

Science.gov (United States)

Freeman, Aakhu TuahNera

This performance guide is designed for teachers to use with students before and after a performance of "Sundiata: Lion King of Mali," adapted by Kim Hines and featuring Griot Alhaji Papa Susso. The guide, called a "Cuesheet," contains seven activity sheets for use in class, addressing: (1) Sundiata: Man & Myth (discusses…

Chlamydia - CDC Fact Sheet

Science.gov (United States)

... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... sheet Pelvic Inflammatory Disease (PID) – CDC fact sheet Gonorrhea – CDC fact sheet STDs Home Page Bacterial Vaginosis ( ...

Laminin-521 Promotes Rat Bone Marrow Mesenchymal Stem Cell Sheet Formation on Light-Induced Cell Sheet Technology

Directory of Open Access Journals (Sweden)

Zhiwei Jiang

2017-01-01

Full Text Available Rat bone marrow mesenchymal stem cell sheets (rBMSC sheets are attractive for cell-based tissue engineering. However, methods of culturing rBMSC sheets are critically limited. In order to obtain intact rBMSC sheets, a light-induced cell sheet method was used in this study. TiO2 nanodot films were coated with (TL or without (TN laminin-521. We investigated the effects of laminin-521 on rBMSCs during cell sheet culturing. The fabricated rBMSC sheets were subsequently assessed to study cell sheet viability, reattachment ability, cell sheet thickness, collagen type I deposition, and multilineage potential. The results showed that laminin-521 could promote the formation of rBMSC sheets with good viability under hyperconfluent conditions. Cell sheet thickness increased from an initial 26.7 ± 1.5 μm (day 5 up to 47.7 ± 3.0 μm (day 10. Moreover, rBMSC sheets maintained their potential of osteogenic, adipogenic, and chondrogenic differentiation. This study provides a new strategy to obtain rBMSC sheets using light-induced cell sheet technology.

Character education in perspective of chemistry pre-service teacher

Science.gov (United States)

Merdekawati, Krisna

2017-12-01

As one of the pre-service teacher education programs, Chemistry Education Department Islamic University of Indonesia (UII) is committed to providing quality education. It is an education that can produce competent and characteristic chemistry pre-service teacher. The focus of research is to describe the perception of students as a potential teacher of chemistry on character education and achievement of character education. The research instruments include questionnaires and observation sheets. Research data show that students have understood the importance of character education and committed to organizing character education later in schools. Students have understood the ways in which character education can be used. The students stated that Chemistry Education Department has tried to equip students with character education. The observation result shows that students generally have character as a pre-service teacher.

Aftershocks: The Role of State Labor Policies in Shaping Teacher Sensemaking, Satisfaction and Exit Decisions in North Carolina

Science.gov (United States)

Feldman, Rachel Carly

2017-01-01

This dissertation examines how teachers respond to state-wide labor reforms. In 2013 and 2014, the state of North Carolina drastically altered compensation for teachers. Policymakers affected labor by attempting to revoke tenure for all teachers (and succeeded in eliminating it for new teachers), discontinuing supplemental pay for advanced…

A Randomized Rounding Approach for Optimization of Test Sheet Composing and Exposure Rate Control in Computer-Assisted Testing

Science.gov (United States)

Wang, Chu-Fu; Lin, Chih-Lung; Deng, Jien-Han

2012-01-01

Testing is an important stage of teaching as it can assist teachers in auditing students' learning results. A good test is able to accurately reflect the capability of a learner. Nowadays, Computer-Assisted Testing (CAT) is greatly improving traditional testing, since computers can automatically and quickly compose a proper test sheet to meet user…

ACER Chemistry Test Item Collection (ACER CHEMTIC Year 12 Supplement).

Science.gov (United States)

Australian Council for Educational Research, Hawthorn.

This publication contains 317 multiple-choice chemistry test items related to topics covered in the Victorian (Australia) Year 12 chemistry course. It allows teachers access to a range of items suitable for diagnostic and achievement purposes, supplementing the ACER Chemistry Test Item Collection--Year 12 (CHEMTIC). The topics covered are: organic…

Superfund fact sheet: The remedial program. Fact sheet

International Nuclear Information System (INIS)

1992-09-01

The fact sheet describes what various actions the EPA can take to clean up hazardous wastes sites. Explanations of how the criteria for environmental and public health risk assessment are determined and the role of state and local governments in site remediation are given. The fact sheet is one in a series providing reference information about Superfund issues and is intended for readers with no formal scientific training

Fact Sheet: Supplemental Proposal: State Plans to Address Emissions during Startup, Shutdown and Malfunction (SSM)

Science.gov (United States)

On September 5, 2014, EPA proposed a rule supplementing and revising its February 2013 proposal to ensure states have plans in place that require industrial facilities across the country to follow air pollution rules during SSM operations.

Radiation protecting sheet

International Nuclear Information System (INIS)

Makiguchi, Hiroshi.

1989-01-01

As protection sheets used in radioactivity administration areas, a thermoplastic polyurethane composition sheet with a thickness of less 0.5 mm, solid content (ash) of less than 5% and a shore D hardness of less than 60 is used. A composite sheet with thickness of less than 0.5 mm laminated or coated with such a thermoplastic polyurethane composition as a surface layer and the thermoplastic polyurethane composition sheet applied with secondary fabrication are used. This can satisfy all of the required properties, such as draping property, abrasion resistance, high breaking strength, necking resistance, endurance strength, as well as chemical resistance and easy burnability in burning furnace. Further, by forming uneveness on the surface by means of embossing, etc. safety problems such as slippage during operation and walking can be overcome. (T.M.)

Automobile sheet metal part production with incremental sheet forming

Directory of Open Access Journals (Sweden)

İsmail DURGUN

2016-02-01

Full Text Available Nowadays, effect of global warming is increasing drastically so it leads to increased interest on energy efficiency and sustainable production methods. As a result of adverse conditions, national and international project platforms, OEMs (Original Equipment Manufacturers, SMEs (Small and Mid-size Manufacturers perform many studies or improve existing methodologies in scope of advanced manufacturing techniques. In this study, advanced manufacturing and sustainable production method "Incremental Sheet Metal Forming (ISF" was used for sheet metal forming process. A vehicle fender was manufactured with or without die by using different toolpath strategies and die sets. At the end of the study, Results have been investigated under the influence of method and parameters used.Keywords: Template incremental sheet metal, Metal forming

Immune function and hematology of male cotton rats (Sigmodon hispidus) in response to food supplementation and methionine

Science.gov (United States)

Webb, R.E.; Leslie, David M.; Lochmiller, R.L.; Masters, R.E.

2003-01-01

We examined effects of supplementation of food quantity and quality (=enhanced methionine) on hematologic and immunologic parameters of wild, but enclosed, adult male cotton rats (Sigmodon hispidus) in north-central Oklahoma. Sheet metal enclosures were stocked with a high density of wild-caught cotton rats (160 animals/ha) and randomly assigned a treatment of no supplementation, mixed-ration supplementation or methionine-enhanced supplementation. Aside from small increases in counts of red blood cells and hematocrit levels, most indices of erythrocytic characteristics were not affected by supplementation with the mixed-ration or enhanced methionine. In contrast, platelet counts were highest in mixed-ration and methionine treatments and counts of total white blood cells were highest with methionine supplementation, albeit relative proportions of different leukocytes did not differ among treatments. Immunologically, neither delayed-type hypersensitivity response nor hemolytic-complement activity differed among treatments. Supplementation of food quantity and quality did not broadly affect hematologic parameters and immune function of male cotton rats, but enhanced platelet and leukocyte counts may confer advantages to overall health. Clarification of the role of such effects on population limitation or regulation requires additional research.

Variation in Teacher Salaries in Georgia: Does the Property Tax Base Matter?

Science.gov (United States)

Winters, John V.

2009-01-01

There is a great deal of variation in teacher salaries across school districts. This is important because districts that pay low salaries are likely to have greater trouble recruiting and retaining quality teachers. Regression analysis reveals that local supplements--payments exceeding the state minimum salary schedule--are affected by a number of…

Geometry of thin liquid sheet flows

Science.gov (United States)

Chubb, Donald L.; Calfo, Frederick D.; Mcconley, Marc W.; Mcmaster, Matthew S.; Afjeh, Abdollah A.

1994-01-01

Incompresible, thin sheet flows have been of research interest for many years. Those studies were mainly concerned with the stability of the flow in a surrounding gas. Squire was the first to carry out a linear, invicid stability analysis of sheet flow in air and compare the results with experiment. Dombrowski and Fraser did an experimental study of the disintegration of sheet flows using several viscous liquids. They also detected the formulation of holes in their sheet flows. Hagerty and Shea carried out an inviscid stability analysis and calculated growth rates with experimental values. They compared their calculated growth rates with experimental values. Taylor studied extensively the stability of thin liquid sheets both theoretically and experimentally. He showed that thin sheets in a vacuum are stable. Brown experimentally investigated thin liquid sheet flows as a method of application of thin films. Clark and Dumbrowski carried out second-order stability analysis for invicid sheet flows. Lin introduced viscosity into the linear stability analysis of thin sheet flows in a vacuum. Mansour and Chigier conducted an experimental study of the breakup of a sheet flow surrounded by high-speed air. Lin et al. did a linear stability analysis that included viscosity and a surrounding gas. Rangel and Sirignano carried out both a linear and nonlinear invisid stability analysis that applies for any density ratio between the sheet liquid and the surrounding gas. Now there is renewed interest in sheet flows because of their possible application as low mass radiating surfaces. The objective of this study is to investigate the fluid dynamics of sheet flows that are of interest for a space radiator system. Analytical expressions that govern the sheet geometry are compared with experimental results. Since a space radiator will operate in a vacuum, the analysis does not include any drag force on the sheet flow.

The Implementation of Pedagogical Content Knowledge (PCK based Guided Inquiry on Science Teacher Students

Directory of Open Access Journals (Sweden)

Lulu Tunjung Biru

2018-05-01

Full Text Available The aim of this study is examining the learning of Integrated Sciences through PCK based guided inquiry on prospective science teacher students. This research method was descriptive qualitative involving 33 science teacher students who taking Integrated Science 1 Subject in academic year 2016/2017. The research instrument used was the observation sheet to know the implementation PCK based guided inquiry. The results showed that the implementation of the activities of lecturer and science teacher students during the learning process using PCK based guided inquiry was very good conducted.

Best Management Practice, Fact Sheet 2. Sheet Flow to Open Space

OpenAIRE

Sample, David; Doumar, Lia

2013-01-01

This publication explains what sheet flow to open space is, where and how it is used, their limitations, routine and nonroutine maintenance, expected costs, and a glossary of terms. This fact sheet is one of a 15-part series on urban stormwater management practices.

Developing Mathematical Resilience of Prospective Math Teachers

Science.gov (United States)

Ariyanto, L.; Herman, T.; Sumarmo, U.; Suryadi, D.

2017-09-01

Prospective math teachers need to develop positive adaptive attitudes toward mathematics that will enable them to continue learning despite having to deal with obstacles and difficulties. This research focuses on the resilience improvement of the prospective mathematic teachers after being treated using problem-based learning based on their basic knowledge on mathematic and their overall knowledge on math. This research used only one group for pre-test and post-test. The result of this research shows that there is improvement on prospective teachers’ resilience after they were given treatment using problem-based learning. One of the factors causing the resilience improvement of the prospective mathematic teachers is the instructions on students’ work sheet. In the instructions, stud ents were asked to write difficulties in solving math problems as well as write down the solution they take to overcome them. This research can be used as a reference for other researchers who want to do the same research related on students’ resiliency o n math and or math lecturers to improve the resilience of prospective teachers to be resilient teachers on math in the future.

Carbon sheet pumping

International Nuclear Information System (INIS)

Ohyabu, N.; Sagara, A.; Kawamura, T.; Motojima, O.; Ono, T.

1993-07-01

A new hydrogen pumping scheme has been proposed which controls recycling of the particles for significant improvement of the energy confinement in toroidal magnetic fusion devices. In this scheme, a part of the vacuum vessel surface near the divertor is covered with carbon sheets of a large surface area. Before discharge initiation, the sheets are baked up to 700 ∼ 1000degC to remove the previously trapped hydrogen atoms. After being cooled down to below ∼ 200degC, the unsaturated carbon sheets trap high energy charge exchange hydrogen atoms effectively during a discharge and overall pumping efficiency can be as high as ∼ 50 %. (author)

Culinary Arts Teachers Manual. Project HIRE.

Science.gov (United States)

Gardner, David C.; And Others

Designed as supplemental material to on-going instruction in the vocational program, this teacher's manual to the Culinary Arts series is intended to accompany three dictionary booklets (available as CE 024 415-417) for use by handicapped students to help them master the core vocabulary taught in the trade. Information presented in the manual…

FDTD modeling of thin impedance sheets

Science.gov (United States)

Luebbers, Raymond J.; Kunz, Karl S.

1991-01-01

Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. In this paper it is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods.

Manipulatives Implementation For Supporting Learning Of Mathematics For Prospective Teachers

Science.gov (United States)

Sulistyaningsih, D.; Mawarsari, V. D.; Hidayah, I.; Dwijanto

2017-04-01

Manipulatives are needed by teachers to facilitate students understand of mathematics which is abstract. As a prospective mathematics teacher, the student must have good skills in making manipulatives. Aims of this study is to describe the implementation of learning courses of manipulative workshop in mathematics education courses by lecturer at Universitas Muhammadiyah Semarang which includes the preparation of learning, general professional ability, the professional capacity specifically, ability of self-development, development class managing, planning and implementation of learning, a way of delivering the material, and evaluation of learning outcomes. Data collection techniques used were questionnaires, interviews, and observation. The research instrument consisted of a questionnaire sheet, sheet observation and interview guides. Validity is determined using data triangulation and triangulation methods. Data were analyzed using an interactive model. The results showed that the average value of activities in preparation for learning, fosters capabilities of general professional, specialized professional, self-development, manage the classroom, implementing the learning, how to deliver the material, and how to evaluate learning outcomes are 79%, 73%, 67%, 75%, 83%, 72%, 64%, and 54%, respectively

Geography Education Research in Serbia: A Teacher's Perspective

Science.gov (United States)

Rajovic, Goran; Bulatovic, Jelisavka

2017-01-01

In all European Union countries have harmonized attitudes on the need and improving the quality geographic of education and his innovating. Modernization of geographic education is unthinkable without quality professional and personal development of teacher's geography. Renewal, modernization and supplement professional knowledge and skills…

Plasma dynamics in current sheets

International Nuclear Information System (INIS)

Bogdanov, S.Yu.; Drejden, G.V.; Kirij, N.P.; AN SSSR, Leningrad

1992-01-01

Plasma dynamics in successive stages of current sheet evolution is investigated on the base of analysis of time-spatial variations of electron density and electrodynamic force fields. Current sheet formation is realized in a two-dimensional magnetic field with zero line under the action of relatively small initial disturbances (linear regimes). It is established that in the limits of the formed sheet is concentrated dense (N e ∼= 10 16 cm -3 ) (T i ≥ 100 eV, bar-Z i ≥ 2) hot pressure of which is balanced by the magnetic action of electrodynamic forces is carried out both plasma compression in the sheet limits and the acceleration along the sheet surface from a middle to narrow side edges

Portfolio as a Means of Promoting Autonomous Learning in Teacher Education: A Quasi-Experimental Study

Science.gov (United States)

Meeus, Wil; Van Petegem, Peter; Meijer, Joost

2008-01-01

Background: The predominant dissertation model used in teacher education courses in Flanders is the "literature study with practical processing". Despite the practical supplement, this traditional model does not fit sufficiently well with autonomous learning as the objective of modern teacher education dissertations. This study reports on the…

46 CFR 232.4 - Balance sheet accounts.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Balance sheet accounts. 232.4 Section 232.4 Shipping... ACTIVITIES UNIFORM FINANCIAL REPORTING REQUIREMENTS Balance Sheet § 232.4 Balance sheet accounts. (a.... (b) Purpose of balance sheet accounts. The balance sheet accounts are intended to disclose the...

Global ice sheet modeling

International Nuclear Information System (INIS)

Hughes, T.J.; Fastook, J.L.

1994-05-01

The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

Sheet production apparatus for removing a crystalline sheet from the surface of a melt using gas jets located above and below the crystalline sheet

Energy Technology Data Exchange (ETDEWEB)

Kellerman, Peter L.; Thronson, Gregory D.

2017-06-14

In one embodiment, a sheet production apparatus comprises a vessel configured to hold a melt of a material. A cooling plate is disposed proximate the melt and is configured to form a sheet of the material on the melt. A first gas jet is configured to direct a gas toward an edge of the vessel. A sheet of a material is translated horizontally on a surface of the melt and the sheet is removed from the melt. The first gas jet may be directed at the meniscus and may stabilize this meniscus or increase local pressure within the meniscus.

Effects of the learning assistant experience on in-service teachers' practices

Science.gov (United States)

Gray, Kara E.; Webb, David C.; Otero, Valerie K.

2012-02-01

The Colorado Learning Assistant (LA) Program serves as a content-specific supplement to standard teacher preparation programs. In addition to transforming undergraduate STEM courses, it recruits and prepares math and science majors for teaching careers by involving university STEM faculty. The research reported here compares the teaching practices of in-service teachers who participated in the LA experience as undergraduates to a comparison group of teachers who did not participate in the LA program as undergraduates but were certified to teach through the same program. We report on teachers' views of assessments and differences in their teaching practices. This analysis is based on interviews with approximately 30 teachers and observations of their classrooms throughout their induction years of teaching. This work considers how the LA program may help improve current teacher preparation models.

Dynamics of Radially Expanding Liquid Sheets

Science.gov (United States)

Majumdar, Nayanika; Tirumkudulu, Mahesh S.

2018-04-01

The process of atomization often involves ejecting thin liquid sheets at high speeds from a nozzle that causes the sheet to flap violently and break up into fine droplets. The flapping of the liquid sheet has long been attributed to the sheet's interaction with the surrounding gas phase. Here, we present experimental evidence to the contrary and show that the flapping is caused by the thinning of the liquid sheet as it spreads out from the nozzle exit. The measured growth rates of the waves agree remarkably well with the predictions of a recent theory that accounts for the sheet's thinning but ignores aerodynamic interactions. We anticipate these results to not only lead to more accurate predictions of the final drop-size distribution but also enable more efficient designs of atomizers.

Buckling and stretching of thin viscous sheets

Science.gov (United States)

O'Kiely, Doireann; Breward, Chris; Griffiths, Ian; Howell, Peter; Lange, Ulrich

2016-11-01

Thin glass sheets are used in smartphone, battery and semiconductor technology, and may be manufactured by producing a relatively thick glass slab and subsequently redrawing it to a required thickness. The resulting sheets commonly possess undesired centerline ripples and thick edges. We present a mathematical model in which a viscous sheet undergoes redraw in the direction of gravity, and show that, in a sufficiently strong gravitational field, buckling is driven by compression in a region near the bottom of the sheet, and limited by viscous resistance to stretching of the sheet. We use asymptotic analysis in the thin-sheet, low-Reynolds-number limit to determine the centerline profile and growth rate of such a viscous sheet.

Metacognitive and multimedia support of experiments in inquiry learning for science teacher preparation

Science.gov (United States)

Bruckermann, Till; Aschermann, Ellen; Bresges, André; Schlüter, Kirsten

2017-04-01

Promoting preservice science teachers' experimentation competency is required to provide a basis for meaningful learning through experiments in schools. However, preservice teachers show difficulties when experimenting. Previous research revealed that cognitive scaffolding promotes experimentation competency by structuring the learning process, while metacognitive and multimedia support enhance reflection. However, these support measures have not yet been tested in combination. Therefore, we decided to use cognitive scaffolding to support students' experimental achievements and supplement it by metacognitive and multimedia scaffolds in the experimental groups. Our research question is to what extent supplementing cognitive support by metacognitive and multimedia scaffolding further promotes experimentation competency. The intervention has been applied in a two-factorial design to a two-month experimental course for 63 biology teacher students in their first bachelor year. Pre-post-test measured experimentation competency in a performance assessment. Preservice teachers worked in groups of four. Therefore, measurement took place at group level (N = 16). Independent observers rated preservice teachers' group performance qualitatively on a theory-based system of categories. Afterwards, experimentation competency levels led to quantitative frequency analysis. The results reveal differing gains in experimentation competency but contrary to our hypotheses. Implications of combining scaffolding measures on promoting experimentation competency are discussed.

Regeneration of rat corpora cavernosa tissue by transplantation of CD133+ cells derived from human bone marrow and placement of biodegradable gel sponge sheet

Directory of Open Access Journals (Sweden)

Shogo Inoue

2017-01-01

Full Text Available The objective is to develop an easier technique for regenerating corpora cavernosa tissue through transplantation of human bone marrow-derived CD133 + cells into a rat corpora cavernosa defect model. We excised 2 mm × 2 mm squares of the right corpora cavernosa of twenty-three 8-week-old male nude rats. Alginate gel sponge sheets supplemented with 1 × 10 4 CD133 + cells were then placed over the excised area of nine rats. Functional and histological evaluations were carried out 8 weeks later. The mean intracavernous pressure/mean arterial pressure ratio for the nine rats (0.34258 ± 0.0831 was significantly higher than that for eight rats with only the excision (0.0580 ± 0.0831, P = 0.0238 and similar to that for five rats for which the penis was exposed, and there was no excision (0.37228 ± 0.1051, P = 0.8266. Immunohistochemical analysis revealed that the nine fully treated rats had venous sinus-like structures and quantitative reverse transcription polymerase chain reaction analysis of extracts from their alginate gel sponge sheets revealed that the amounts of mRNA encoding the nerve growth factor (NGF, and vascular endothelial growth factor (VEGF were significantly higher than those for rats treated with alginate gel sheets without cell supplementation (NGF: P = 0.0309; VEGF: P < 0.0001. These findings show that transplantation of CD133 + cells accelerates functional and histological recovery in the corpora cavernosa defect model.

Ohm's law for a current sheet

Science.gov (United States)

Lyons, L. R.; Speiser, T. W.

1985-01-01

The paper derives an Ohm's law for single-particle motion in a current sheet, where the magnetic field reverses in direction across the sheet. The result is considerably different from the resistive Ohm's law often used in MHD studies of the geomagnetic tail. Single-particle analysis is extended to obtain a self-consistency relation for a current sheet which agrees with previous results. The results are applicable to the concept of reconnection in that the electric field parallel to the current is obtained for a one-dimensional current sheet with constant normal magnetic field. Dissipated energy goes directly into accelerating particles within the current sheet.

Composition through Construction: A Less Teacher-Directed Approach (EJ Update).

Science.gov (United States)

Tabachnick, Vicki

1992-01-01

Questions traditional composition techniques and their effects on student thinking and problem solving. Demonstrates how one high school English teacher responded to these classroom issues by reading relevant research and supplementing it with a study conducted on her own students. (HB)

The Music Industry Conference Guide for Music Educators. A Supplement to the Music Educators Journal.

Science.gov (United States)

Music Educators Journal, 1988

1988-01-01

This supplement is a comprehensive guide to the music industry designed for music teachers. Included are tips for contacting music businesses and suggestions on ordering music, robes, instruments, computer software, and other supplies. Includes an annotated directory of Music Industry Conference members. (JDH)

Accelerated Reader Program: What Do Teachers Really Think?

Science.gov (United States)

Smith, Amy Frances; Westberg, Karen; Hejny, Anne

2017-01-01

What do teachers really think about the Accelerated Reader program, a widely used supplemental, independent reading program in which their students read fiction and non-fiction books of their choice and take brief online comprehension quizzes about the books? The Accelerated Reader (AR) program was designed by Renaissance Learning Company to…

Adjustable focus laser sheet module for generating constant maximum width sheets for use in optical flow diagnostics

International Nuclear Information System (INIS)

Hult, J; Mayer, S

2011-01-01

A general design of a laser light sheet module with adjustable focus is presented, where the maximum sheet width is preserved over a fixed region. In contrast, conventional focusing designs are associated with a variation in maximum sheet width with focal position. A four lens design is proposed here, where the first three lenses are employed for focusing, and the last for sheet expansion. A maximum sheet width of 1100 µm was maintained over a 50 mm long distance, for focal distances ranging from 75 to 500 mm, when a 532 nm laser beam with a beam quality factor M 2 = 29 was used for illumination

Individual Variables, Attitudes towards English and Being a Teacher: A study on Prospective Teachers of English

Directory of Open Access Journals (Sweden)

Berna Güryay

2016-05-01

Full Text Available The achievement in learning a foreign language depends not only on cognitive factors such as intelligence, aptitude etc., but also on affective factors such as attitude and motivation. As the main branch of prospective teachers of English is teaching a language, their attitudes towards English and towards being a teacher are of vital importance in their future careers. The purpose of this descriptive study is to determine whether the attitudes of the students of English Language Teaching Department towards English affect their attitudes towards being a teacher of English and whether the students’ attitudes indicate significant differences with regard to individual variables such as gender, class, the types of High Schools from which they have graduated, their socio-economic background, and whether there is a teacher in their family. The sample group of the study were composed 540 prospective English teachers of the first, second, third and fourth year students of the Department of English Language Teaching at Buca Faculty of Education at Dokuz Eylül University, İzmir. For data collection, personal information sheet, the scale for attitudes towards English developed by Altunay (2002 (Alpha Reliability Coefficient: 0.96 and the scale for attitudes towards Being a Teacher developed by Semerci (1999 (Alpha Reliability Coefficient: 0.68 were used. The results indicate that the more positive the students’ attitudes towards English are, the more positive the students’ attitudes towards teaching profession are. Fur thermore, when attitudes towards English and towards being a teacher are compared,” it is indicated that the students’ attitudes towards English are a little bit higher.

Collisionless current sheet equilibria

Science.gov (United States)

Neukirch, T.; Wilson, F.; Allanson, O.

2018-01-01

Current sheets are important for the structure and dynamics of many plasma systems. In space and astrophysical plasmas they play a crucial role in activity processes, for example by facilitating the release of magnetic energy via processes such as magnetic reconnection. In this contribution we will focus on collisionless plasma systems. A sensible first step in any investigation of physical processes involving current sheets is to find appropriate equilibrium solutions. The theory of collisionless plasma equilibria is well established, but over the past few years there has been a renewed interest in finding equilibrium distribution functions for collisionless current sheets with particular properties, for example for cases where the current density is parallel to the magnetic field (force-free current sheets). This interest is due to a combination of scientific curiosity and potential applications to space and astrophysical plasmas. In this paper we will give an overview of some of the recent developments, discuss their potential applications and address a number of open questions.

Supporting teachers and children in schools: the effectiveness and cost-effectiveness of the Incredible Years teacher classroom management programme in primary school children: a cluster randomised controlled trial, with parallel economic and process evaluations.

Science.gov (United States)

Ford, Tamsin; Edwards, Vanessa; Sharkey, Siobhan; Ukoumunne, Obioha C; Byford, Sarah; Norwich, Brahm; Logan, Stuart

2012-08-30

Childhood antisocial behaviour has high immediate and long-term costs for society and the individual, particularly in relation to mental health and behaviours that jeopardise health. Managing challenging behaviour is a commonly reported source of stress and burn out among teachers, ultimately resulting in a substantial number leaving the profession. Interventions to improve parenting do not transfer easily to classroom-based problems and the most vulnerable parents may not be easily able to access them. Honing teachers' skills in proactive behaviour management and the promotion of socio-emotional regulation, therefore, has the potential to improve both child and teacher mental health and well-being and the advantage that it might potentially benefit all the children subsequently taught by any teacher that accesses the training. Cluster randomised controlled trial (RCT) of the Incredible Years teacher classroom management (TCM) course with combined economic and process evaluations.One teacher of children aged 4-9 years, from 80 schools in the South West Peninsula will be randomised to attend the TCM (intervention arm) or to "teach as normal" (control arm). The primary outcome measure will be the total difficulties score from the Strengths and Difficulties Questionnaire (SDQ) completed by the current class teachers prior to randomisation, and at 9, 18 and 30 months follow-up, supplemented by parent SDQs. Secondary measures include academic attainment (teacher report supplemented by direct measurement in a sub-sample), children's enjoyment of school, and teacher reports of their professional self-efficacy, and levels of burn out and stress, supplemented by structured observations of teachers classroom management skills in a subsample. Cost data for the economic evaluation will be based on parental reports of services accessed. Cost-effectiveness, using the SDQ as the measure of effect, will be examined over the period of the RCT and over the longer term using decision

17 CFR 210.6-04 - Balance sheets.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Balance sheets. 210.6-04... sheets. This rule is applicable to balance sheets filed by registered investment companies except for... of this part. Balance sheets filed under this rule shall comply with the following provisions: Assets...

Impacting the Science Community through Teacher Development: Utilizing Virtual Learning.

Science.gov (United States)

Boulay, Rachel; van Raalte, Lisa

2014-01-01

Commitment to the STEM (science, technology, engineering, math) pipeline is slowly declining despite the need for professionals in the medical field. Addressing this, the John A. Burns School of Medicine developed a summer teacher-training program with a supplemental technology-learning component to improve science teachers' knowledge and skills of Molecular Biology. Subsequently, students' skills, techniques, and application of molecular biology are impacted. Science teachers require training that will prepare them for educating future professionals and foster interest in the medical field. After participation in the program and full access to the virtual material, twelve high school science teachers completed a final written reflective statement to evaluate their experiences. Using thematic analysis, knowledge and classroom application were investigated in this study. Results were two-fold: teachers identified difference areas of gained knowledge from the teacher-training program and teachers' reporting various benefits in relation to curricula development after participating in the program. It is concluded that participation in the program and access to the virtual material will impact the science community by updating teacher knowledge and positively influencing students' experience with science.

Ice sheet in peril

DEFF Research Database (Denmark)

Hvidberg, Christine Schøtt

2016-01-01

Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions...

The transposition of the balance sheet to financial and functional balance sheet. Research and development

Directory of Open Access Journals (Sweden)

Liana GĂDĂU

2015-09-01

Full Text Available As the title suggests, through this paper we want to highlight the necessity of treating again the content and the form of the balance sheet in order to adapt it to a more efficient analysis, this way surpassing the informational valences of the classic balance sheet. The functional and the financial balance sheet will be taken into account. These models of balance sheet permit the complex analyses regarding the solvability or the bankruptcy risk of an enterprise to take place, and also other analyses, like the analysis of the structure and the financial/ functional equilibrium, the analysis of the company on operating cycles and their role in the functioning of the company. Through the particularities offered by each of these two models of balance sheet, we want to present the advantages of a superior informing. This content of this material is based on a vast investigation of the specialized literature.

Ice_Sheets_CCI: Essential Climate Variables for the Greenland Ice Sheet

Science.gov (United States)

Forsberg, R.; Sørensen, L. S.; Khan, A.; Aas, C.; Evansberget, D.; Adalsteinsdottir, G.; Mottram, R.; Andersen, S. B.; Ahlstrøm, A.; Dall, J.; Kusk, A.; Merryman, J.; Hvidberg, C.; Khvorostovsky, K.; Nagler, T.; Rott, H.; Scharrer, M.; Shepard, A.; Ticconi, F.; Engdahl, M.

2012-04-01

As part of the ESA Climate Change Initiative (www.esa-cci.org) a long-term project "ice_sheets_cci" started January 1, 2012, in addition to the existing 11 projects already generating Essential Climate Variables (ECV) for the Global Climate Observing System (GCOS). The "ice_sheets_cci" goal is to generate a consistent, long-term and timely set of key climate parameters for the Greenland ice sheet, to maximize the impact of European satellite data on climate research, from missions such as ERS, Envisat and the future Sentinel satellites. The climate parameters to be provided, at first in a research context, and in the longer perspective by a routine production system, would be grids of Greenland ice sheet elevation changes from radar altimetry, ice velocity from repeat-pass SAR data, as well as time series of marine-terminating glacier calving front locations and grounding lines for floating-front glaciers. The ice_sheets_cci project will involve a broad interaction of the relevant cryosphere and climate communities, first through user consultations and specifications, and later in 2012 optional participation in "best" algorithm selection activities, where prototype climate parameter variables for selected regions and time frames will be produced and validated using an objective set of criteria ("Round-Robin intercomparison"). This comparative algorithm selection activity will be completely open, and we invite all interested scientific groups with relevant experience to participate. The results of the "Round Robin" exercise will form the algorithmic basis for the future ECV production system. First prototype results will be generated and validated by early 2014. The poster will show the planned outline of the project and some early prototype results.

AI applications in sheet metal forming

CERN Document Server

Hussein, Hussein

2017-01-01

This book comprises chapters on research work done around the globe in the area of artificial intelligence (AI) applications in sheet metal forming. The first chapter offers an introduction to various AI techniques and sheet metal forming, while subsequent chapters describe traditional procedures/methods used in various sheet metal forming processes, and focus on the automation of those processes by means of AI techniques, such as KBS, ANN, GA, CBR, etc. Feature recognition and the manufacturability assessment of sheet metal parts, process planning, strip-layout design, selecting the type and size of die components, die modeling, and predicting die life are some of the most important aspects of sheet metal work. Traditionally, these activities are highly experience-based, tedious and time consuming. In response, researchers in several countries have applied various AI techniques to automate these activities, which are covered in this book. This book will be useful for engineers working in sheet metal industri...

Effect of Temperature and Sheet Temper on Isothermal Solidification Kinetics in Clad Aluminum Brazing Sheet

Science.gov (United States)

Benoit, Michael J.; Whitney, Mark A.; Wells, Mary A.; Winkler, Sooky

2016-09-01

Isothermal solidification (IS) is a phenomenon observed in clad aluminum brazing sheets, wherein the amount of liquid clad metal is reduced by penetration of the liquid clad into the core. The objective of the current investigation is to quantify the rate of IS through the use of a previously derived parameter, the Interface Rate Constant (IRC). The effect of peak temperature and initial sheet temper on IS kinetics were investigated. The results demonstrated that IS is due to the diffusion of silicon (Si) from the liquid clad layer into the solid core. Reduced amounts of liquid clad at long liquid duration times, a roughened sheet surface, and differences in resolidified clad layer morphology between sheet tempers were observed. Increased IS kinetics were predicted at higher temperatures by an IRC model as well as by experimentally determined IRC values; however, the magnitudes of these values are not in good agreement due to deficiencies in the model when applied to alloys. IS kinetics were found to be higher for sheets in the fully annealed condition when compared with work-hardened sheets, due to the influence of core grain boundaries providing high diffusivity pathways for Si diffusion, resulting in more rapid liquid clad penetration.

Energy information sheets

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-07-01

The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

Experiments on sheet metal shearing

OpenAIRE

Gustafsson, Emil

2013-01-01

Within the sheet metal industry, different shear cutting technologies are commonly used in several processing steps, e.g. in cut to length lines, slitting lines, end cropping etc. Shearing has speed and cost advantages over competing cutting methods like laser and plasma cutting, but involves large forces on the equipment and large strains in the sheet material.Numerical models to predict forces and sheared edge geometry for different sheet metal grades and different shear parameter set-ups a...

Predicting Pulsar Scintillation from Refractive Plasma Sheets

Science.gov (United States)

Simard, Dana; Pen, Ue-Li

2018-05-01

The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along sheets in the ionized interstellar medium, such as those due to Alfvén waves propagating along current sheets. If these sheets are closely aligned to our line-of-sight to the pulsar, high bending angles arise at the wave crests and a selection effect causes alignment of images produced at different crests, similar to grazing reflection off of a lake. Using geometric optics, we develop a simple parameterized model of these corrugated sheets that can be constrained with a single observation and that makes observable predictions for variations in the scintillation of the pulsar over time and frequency. This model reveals qualitative differences between lensing from overdense and underdense corrugated sheets: Only if the sheet is overdense compared to the surrounding interstellar medium can the lensed images be brighter than the line-of-sight image to the pulsar, and the faint lensed images are closer to the pulsar at higher frequencies if the sheet is underdense, but at lower frequencies if the sheet is overdense.

Energized Oxygen : Speiser Current Sheet Bifurcation

Science.gov (United States)

George, D. E.; Jahn, J. M.

2017-12-01

A single population of energized Oxygen (O+) is shown to produce a cross-tail bifurcated current sheet in 2.5D PIC simulations of the magnetotail without the influence of magnetic reconnection. Treatment of oxygen in simulations of space plasmas, specifically a magnetotail current sheet, has been limited to thermal energies despite observations of and mechanisms which explain energized ions. We performed simulations of a homogeneous oxygen background, that has been energized in a physically appropriate manner, to study the behavior of current sheets and magnetic reconnection, specifically their bifurcation. This work uses a 2.5D explicit Particle-In-a-Cell (PIC) code to investigate the dynamics of energized heavy ions as they stream Dawn-to-Dusk in the magnetotail current sheet. We present a simulation study dealing with the response of a current sheet system to energized oxygen ions. We establish a, well known and studied, 2-species GEM Challenge Harris current sheet as a starting point. This system is known to eventually evolve and produce magnetic reconnection upon thinning of the current sheet. We added a uniform distribution of thermal O+ to the background. This 3-species system is also known to eventually evolve and produce magnetic reconnection. We add one additional variable to the system by providing an initial duskward velocity to energize the O+. We also traced individual particle motion within the PIC simulation. Three main results are shown. First, energized dawn- dusk streaming ions are clearly seen to exhibit sustained Speiser motion. Second, a single population of heavy ions clearly produces a stable bifurcated current sheet. Third, magnetic reconnection is not required to produce the bifurcated current sheet. Finally a bifurcated current sheet is compatible with the Harris current sheet model. This work is the first step in a series of investigations aimed at studying the effects of energized heavy ions on magnetic reconnection. This work differs

Experimental formability analysis of bondal sandwich sheet

Science.gov (United States)

Kami, Abdolvahed; Banabic, Dorel

2018-05-01

Metal/polymer/metal sandwich sheets have recently attracted the interests of industries like automotive industry. These sandwich sheets have superior properties over single-layer metallic sheets including good sound and vibration damping and light weight. However, the formability of these sandwich sheets should be enhanced which requires more research. In this paper, the formability of Bondal sheet (DC06/viscoelastic polymer/DC06 sandwich sheet) was studied through different types of experiments. The mechanical properties of Bondal were determined by uniaxial tensile tests. Hemispherical punch stretching and hydraulic bulge tests were carried out to determine the forming limit diagram (FLD) of Bondal. Furthermore, cylindrical and square cup drawing tests were performed in dry and oil lubricated conditions. These tests were conducted at different blank holding forces (BHFs). An interesting observation about Bondal sheet deep drawing was obtaining of higher drawing depths at dry condition in comparison with oil-lubricated condition.

Ice sheet hydrology - a review

International Nuclear Information System (INIS)

Jansson, Peter; Naeslund, Jens-Ove; Rodhe, Lars

2007-03-01

This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

Ice sheet hydrology - a review

Energy Technology Data Exchange (ETDEWEB)

Jansson, Peter; Naeslund, Jens-Ove [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden); Rodhe, Lars [Geological Survey of Sweden, Uppsala (Sweden)

2007-03-15

This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

Disintegration of liquid sheets

Science.gov (United States)

Mansour, Adel; Chigier, Norman

1990-01-01

The development, stability, and disintegration of liquid sheets issuing from a two-dimensional air-assisted nozzle is studied. Detailed measurements of mean drop size and velocity are made using a phase Doppler particle analyzer. Without air flow the liquid sheet converges toward the axis as a result of surface tension forces. With airflow a quasi-two-dimensional expanding spray is formed. The air flow causes small variations in sheet thickness to develop into major disturbances with the result that disruption starts before the formation of the main break-up region. In the two-dimensional variable geometry air-blast atomizer, it is shown that the air flow is responsible for the formation of large, ordered, and small chaotic 'cell' structures.

Root-growth-inhibiting sheet

Science.gov (United States)

Burton, F.G.; Cataldo, D.A.; Cline, J.F.; Skiens, W.E.; Van Voris, P.

1993-01-26

In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a geotextile'' and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

Root-growth-inhibiting sheet

Science.gov (United States)

Burton, Frederick G.; Cataldo, Dominic A.; Cline, John F.; Skiens, W. Eugene; Van Voris, Peter

1993-01-01

In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a "geotextile" and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

Mobility Balance Sheet 2009

International Nuclear Information System (INIS)

Jorritsma, P.; Derriks, H.; Francke, J.; Gordijn, H.; Groot, W.; Harms, L.; Van der Loop, H.; Peer, S.; Savelberg, F.; Wouters, P.

2009-06-01

The Mobility Balance Sheet provides an overview of the state of the art of mobility in the Netherlands. In addition to describing the development of mobility this report also provides explanations for the growth of passenger and freight transport. Moreover, the Mobility Balance Sheet also focuses on a topical theme: the effects of economic crises on mobility. [nl

Safety advice sheets

CERN Multimedia

HSE Unit

2013-01-01

You never know when you might be faced with questions such as: when/how should I dispose of a gas canister? Where can I find an inspection report? How should I handle/store/dispose of a chemical substance…?   The SI section of the DGS/SEE Group is primarily responsible for safety inspections, evaluating the safety conditions of equipment items, premises and facilities. On top of this core task, it also regularly issues “Safety Advice Sheets” on various topics, designed to be of assistance to users but also to recall and reinforce safety rules and procedures. These clear and concise sheets, complete with illustrations, are easy to display in the appropriate areas. The following safety advice sheets have been issued so far: Other sheets will be published shortly. Suggestions are welcome and should be sent to the SI section of the DGS/SEE Group. Please send enquiries to general-safety-visits.service@cern.ch.

Manifold free multiple sheet superplastic forming

Science.gov (United States)

Elmer, John W.; Bridges, Robert L.

2004-01-13

Fluid-forming compositions in a container attached to enclosed adjacent sheets are heated to relatively high temperatures to generate fluids (gases) that effect inflation of the sheets. Fluid rates to the enclosed space between the sheets can be regulated by the canal from the container. Inflated articles can be produced by a continuous, rather than batch-type, process.

21 CFR 880.5180 - Burn sheet.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Burn sheet. 880.5180 Section 880.5180 Food and... Burn sheet. (a) Identification. A burn sheet is a device made of a porous material that is wrapped aroung a burn victim to retain body heat, to absorb wound exudate, and to serve as a barrier against...

Sheet-bulk metal forming – forming of functional components from sheet metals

Directory of Open Access Journals (Sweden)

Merklein Marion

2015-01-01

Full Text Available The paper gives an overview on the application of sheet-bulk metal forming operations in both scientific and industrial environment. Beginning with the need for an innovative forming technology, the definition of this new process class is introduced. The rising challenges of the application of bulk metal forming operations on sheet metals are presented and the demand on a holistic investigation of this topic is motivated. With the help of examples from established production processes, the latest state of technology and the lack on fundamental knowledge is shown. Furthermore, perspectives regarding new research topics within sheet-bulk metal forming are presented. These focus on processing strategies to improve the quality of functional components by the application of process-adapted semi-finished products as well as the local adaption of the tribological system.

Reconstructing the last Irish Ice Sheet 2: a geomorphologically-driven model of ice sheet growth, retreat and dynamics

Science.gov (United States)

Greenwood, Sarah L.; Clark, Chris D.

2009-12-01

The ice sheet that once covered Ireland has a long history of investigation. Much prior work focussed on localised evidence-based reconstructions and ice-marginal dynamics and chronologies, with less attention paid to an ice sheet wide view of the first order properties of the ice sheet: centres of mass, ice divide structure, ice flow geometry and behaviour and changes thereof. In this paper we focus on the latter aspect and use our new, countrywide glacial geomorphological mapping of the Irish landscape (>39 000 landforms), and our analysis of the palaeo-glaciological significance of observed landform assemblages (article Part 1), to build an ice sheet reconstruction yielding these fundamental ice sheet properties. We present a seven stage model of ice sheet evolution, from initiation to demise, in the form of palaeo-geographic maps. An early incursion of ice from Scotland likely coalesced with local ice caps and spread in a south-westerly direction 200 km across Ireland. A semi-independent Irish Ice Sheet was then established during ice sheet growth, with a branching ice divide structure whose main axis migrated up to 140 km from the west coast towards the east. Ice stream systems converging on Donegal Bay in the west and funnelling through the North Channel and Irish Sea Basin in the east emerge as major flow components of the maximum stages of glaciation. Ice cover is reconstructed as extending to the continental shelf break. The Irish Ice Sheet became autonomous (i.e. separate from the British Ice Sheet) during deglaciation and fragmented into multiple ice masses, each decaying towards the west. Final sites of demise were likely over the mountains of Donegal, Leitrim and Connemara. Patterns of growth and decay of the ice sheet are shown to be radically different: asynchronous and asymmetric in both spatial and temporal domains. We implicate collapse of the ice stream system in the North Channel - Irish Sea Basin in driving such asymmetry, since rapid

Pre-LGM Northern Hemisphere ice sheet topography

Directory of Open Access Journals (Sweden)

J. Kleman

2013-10-01

Full Text Available We here reconstruct the paleotopography of Northern Hemisphere ice sheets during the glacial maxima of marine isotope stages (MIS 5b and 4.We employ a combined approach, blending geologically based reconstruction and numerical modeling, to arrive at probable ice sheet extents and topographies for each of these two time slices. For a physically based 3-D calculation based on geologically derived 2-D constraints, we use the University of Maine Ice Sheet Model (UMISM to calculate ice sheet thickness and topography. The approach and ice sheet modeling strategy is designed to provide robust data sets of sufficient resolution for atmospheric circulation experiments for these previously elusive time periods. Two tunable parameters, a temperature scaling function applied to a spliced Vostok–GRIP record, and spatial adjustment of the climatic pole position, were employed iteratively to achieve a good fit to geological constraints where such were available. The model credibly reproduces the first-order pattern of size and location of geologically indicated ice sheets during marine isotope stages (MIS 5b (86.2 kyr model age and 4 (64 kyr model age. From the interglacial state of two north–south obstacles to atmospheric circulation (Rocky Mountains and Greenland, by MIS 5b the emergence of combined Quebec–central Arctic and Scandinavian–Barents-Kara ice sheets had increased the number of such highland obstacles to four. The number of major ice sheets remained constant through MIS 4, but the merging of the Cordilleran and the proto-Laurentide Ice Sheet produced a single continent-wide North American ice sheet at the LGM.

Supporting teachers and children in schools: the effectiveness and cost-effectiveness of the incredible years teacher classroom management programme in primary school children: a cluster randomised controlled trial, with parallel economic and process evaluations

Directory of Open Access Journals (Sweden)

Ford Tamsin

2012-08-01

Full Text Available Abstract Background Childhood antisocial behaviour has high immediate and long-term costs for society and the individual, particularly in relation to mental health and behaviours that jeopardise health. Managing challenging behaviour is a commonly reported source of stress and burn out among teachers, ultimately resulting in a substantial number leaving the profession. Interventions to improve parenting do not transfer easily to classroom-based problems and the most vulnerable parents may not be easily able to access them. Honing teachers’ skills in proactive behaviour management and the promotion of socio-emotional regulation, therefore, has the potential to improve both child and teacher mental health and well-being and the advantage that it might potentially benefit all the children subsequently taught by any teacher that accesses the training. Methods/Design Cluster randomised controlled trial (RCT of the Incredible Years teacher classroom management (TCM course with combined economic and process evaluations. One teacher of children aged 4–9 years, from 80 schools in the South West Peninsula will be randomised to attend the TCM (intervention arm or to “teach as normal” (control arm. The primary outcome measure will be the total difficulties score from the Strengths and Difficulties Questionnaire (SDQ completed by the current class teachers prior to randomisation, and at 9, 18 and 30 months follow-up, supplemented by parent SDQs. Secondary measures include academic attainment (teacher report supplemented by direct measurement in a sub-sample, children’s enjoyment of school, and teacher reports of their professional self-efficacy, and levels of burn out and stress, supplemented by structured observations of teachers classroom management skills in a subsample. Cost data for the economic evaluation will be based on parental reports of services accessed. Cost-effectiveness, using the SDQ as the measure of effect, will be examined

Research on Al-alloy sheet forming formability during warm/hot sheet hydroforming based on elliptical warm bulging test

Science.gov (United States)

Cai, Gaoshen; Wu, Chuanyu; Gao, Zepu; Lang, Lihui; Alexandrov, Sergei

2018-05-01

An elliptical warm/hot sheet bulging test under different temperatures and pressure rates was carried out to predict Al-alloy sheet forming limit during warm/hot sheet hydroforming. Using relevant formulas of ultimate strain to calculate and dispose experimental data, forming limit curves (FLCS) in tension-tension state of strain (TTSS) area are obtained. Combining with the basic experimental data obtained by uniaxial tensile test under the equivalent condition with bulging test, complete forming limit diagrams (FLDS) of Al-alloy are established. Using a quadratic polynomial curve fitting method, material constants of fitting function are calculated and a prediction model equation for sheet metal forming limit is established, by which the corresponding forming limit curves in TTSS area can be obtained. The bulging test and fitting results indicated that the sheet metal FLCS obtained were very accurate. Also, the model equation can be used to instruct warm/hot sheet bulging test.

On Jovian plasma sheet structure

International Nuclear Information System (INIS)

Khurana, K.K.; Kivelson, M.G.

1989-01-01

The authors evaluate several models of Jovian plasma sheet structure by determining how well they organize several aspects of the observed Voyager 2 magnetic field characteristics as a function of Jovicentric radial distance. It is shown that in the local time sector of the Voyager 2 outbound pass (near 0300 LT) the published hinged-magnetodisc models with wave (i.e., models corrected for finite wave velocity effects) are more successful than the published magnetic anomaly model in predicting locations of current sheet crossings. They also consider the boundary between the plasma sheet and the magnetotail lobe which is expected to vary slowly with radial distance. They use this boundary location as a further test of the models of the magnetotail. They show that the compressional MHD waves have much smaller amplitude in the lobes than in the plasma sheet and use this criterion to refine the identification of the plasma-sheet-lobe boundary. When the locations of crossings into and out of the lobes are examined, it becomes evident that the magnetic-anomaly model yields a flaring plasma sheet with a halfwidth of ∼ 3 R J at a radial distance of 20 R J and ∼ 12 R J at a radial distance of 100 R J . The hinged-magnetodisc models with wave, on the other hand, predict a halfwidth of ∼ 3.5 R J independent of distance beyond 20 R J . New optimized versions of the two models locate both the current sheet crossings and lobe encounters equally successfully. The optimized hinged-magnetodisc model suggests that the wave velocity decreases with increasing radial distance. The optimized magnetic anomaly model yields lower velocity contrast than the model of Vasyliunas and Dessler (1981)

Rubella - Fact Sheet for Parents

Science.gov (United States)

... and 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Rubéola The best way ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

Cell sheet technology and cell patterning for biofabrication

Energy Technology Data Exchange (ETDEWEB)

Hannachi, Imen Elloumi; Yamato, Masayuki; Okano, Teruo [Institute of Advanced Biomedical Engineering and Science, Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo (Japan)

2009-06-01

We have developed cell sheet technology as a modern method for the fabrication of functional tissue-like and organ-like structures. This technology allows for a sheet of interconnected cells and cells in full contact with their natural extracellular environment to be obtained. A cell sheet can be patterned and composed according to more than one cell type. The key technology of cell sheet engineering is that a fabricated cell sheet can be harvested and transplanted utilizing temperature-responsive surfaces. In this review, we summarize different aspects of cell sheet engineering and provide a survey of the application of cell sheets as a suitable material for biofabrication and clinics. Moreover, since cell micropatterning is a key tool for cell sheet engineering, in this review we focus on the introduction of our approaches to cell micropatterning and cell co-culture to the principles of automation and how they can be subjected to easy robotics programming. Finally, efforts towards making cell sheet technology suitable for biofabrication and robotic biofabrication are also summarized. (topical review)

Fact sheet on thyroid test in Fukushima prefecture

International Nuclear Information System (INIS)

Hiranuma, Yuri

2017-01-01

Fukushima Prefecture chose about 360,000 people who were 18 years old or younger at the time of the accident at Fukushima Daiichi NPS on March 11, 2011, and started thyroid test as part of the prefectural health survey on October 9, 2011. The survey is entrusted to Fukushima Medical University of Medicine from Fukushima Prefecture. This fact sheet summarizes the current state of thyroid test in Fukushima Prefecture. A considerable amount of data and related information have been accumulated in the seventh year from the beginning. However, especially the information disclosed in English by people concerned combined the results of the second round, which was not analyzed properly, with those of the first round. This fact gives a suspicion of intention to deny the possibility of radiation influence in such a way as to make it invisible even if there was the influence. This study firstly prepared an English fact sheet to convey the actual situation in English. However, since some official information/views were contained in papers only available in English, this study also prepared the Japanese version for enabling to grasp the current situation. The Japanese version is supplemented with explanation rather than the Japanese translation of the English version, in order to make it easier to understand. The future of thyroid test is a topic that is causing controversy. Now that the transparency, scientific fairness, and the data integrity of Fukushima Medical University are suspected, it is extremely important that an independent analysis in the true sense is to be performed by qualified experts based on the latest evidence. (A.O.)

Energy information sheets

Energy Technology Data Exchange (ETDEWEB)

1993-12-02

The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. Written for the general public, the EIA publication Energy Information Sheets was developed to provide information on various aspects of fuel production, prices, consumption and capability. The information contained herein pertains to energy data as of December 1991. Additional information on related subject matter can be found in other EIA publications as referenced at the end of each sheet.

Weld Repair of Thin Aluminum Sheet

Science.gov (United States)

Beuyukian, C. S.; Mitchell, M. J.

1986-01-01

Weld repairing of thin aluminum sheets now possible, using niobium shield and copper heat sinks. Refractory niobium shield protects aluminum adjacent to hole, while copper heat sinks help conduct heat away from repair site. Technique limits tungsten/inert-gas (TIG) welding bombardment zone to melt area, leaving surrounding areas around weld unaffected. Used successfully to repair aluminum cold plates on Space Shuttle, Commercial applications, especially in sealing fractures, dents, and holes in thin aluminum face sheets or clad brazing sheet in cold plates, heat exchangers, coolers, and Solar panels. While particularly suited to thin aluminum sheet, this process also used in thicker aluminum material to prevent surface damage near weld area.

Modeling the Alzheimer Abeta17-42 fibril architecture: tight intermolecular sheet-sheet association and intramolecular hydrated cavities.

Science.gov (United States)

Zheng, Jie; Jang, Hyunbum; Ma, Buyong; Tsai, Chung-Jun; Nussinov, Ruth

2007-11-01

We investigate Abeta(17-42) protofibril structures in solution using molecular dynamics simulations. Recently, NMR and computations modeled the Abeta protofibril as a longitudinal stack of U-shaped molecules, creating an in-parallel beta-sheet and loop spine. Here we study the molecular architecture of the fibril formed by spine-spine association. We model in-register intermolecular beta-sheet-beta-sheet associations and study the consequences of Alzheimer's mutations (E22G, E22Q, E22K, and M35A) on the organization. We assess the structural stability and association force of Abeta oligomers with different sheet-sheet interfaces. Double-layered oligomers associating through the C-terminal-C-terminal interface are energetically more favorable than those with the N-terminal-N-terminal interface, although both interfaces exhibit high structural stability. The C-terminal-C-terminal interface is essentially stabilized by hydrophobic and van der Waals (shape complementarity via M35-M35 contacts) intermolecular interactions, whereas the N-terminal-N-terminal interface is stabilized by hydrophobic and electrostatic interactions. Hence, shape complementarity, or the "steric zipper" motif plays an important role in amyloid formation. On the other hand, the intramolecular Abeta beta-strand-loop-beta-strand U-shaped motif creates a hydrophobic cavity with a diameter of 6-7 A, allowing water molecules and ions to conduct through. The hydrated hydrophobic cavities may allow optimization of the sheet association and constitute a typical feature of fibrils, in addition to the tight sheet-sheet association. Thus, we propose that Abeta fiber architecture consists of alternating layers of tight packing and hydrated cavities running along the fibrillar axis, which might be possibly detected by high-resolution imaging.

Improved ice loss estimate of the northwestern Greenland ice sheet

DEFF Research Database (Denmark)

Kjeldsen, Kristian Kjellerup; Khan, Shfaqat Abbas; Wahr, J.

2013-01-01

We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change...... estimate, we supplement the ICESat data with altimeter surveys from NASA's Airborne Topographic Mapper from 2002 to 2010 and NASA's Land, Vegetation and Ice Sensor from 2010. The Airborne data are mainly concentrated along the ice margin and thus have a significant impact on the estimate of the volume...... change. Our results show that adding Airborne Topographic Mapper and Land, Vegetation and Ice Sensor data to the ICESat data increases the catchment-wide estimate of ice volume loss by 11%, mainly due to an improved volume loss estimate along the ice sheet margin. Furthermore, our results show...

Sheet pinch devices

International Nuclear Information System (INIS)

Anderson, O.A.; Baker, W.R.; Ise, J. Jr.; Kunkel, W.B.; Pyle, R.V.; Stone, J.M.

1958-01-01

Three types of sheet-like discharges are being studied at Berkeley. The first of these, which has been given the name 'Triax', consists of a cylindrical plasma sleeve contained between two coaxial conducting cylinders A theoretical analysis of the stability of the cylindrical sheet plasma predicts the existence of a 'sausage-mode' instability which is, however, expected to grow more slowly than in the case of the unstabilized linear pinch (by the ratio of the radial dimensions). The second pinch device employs a disk shaped discharge with radial current guided between flat metal plates, this configuration being identical to that of the flat hydromagnetic capacitor without external magnetic field. A significant feature of these configurations is the absence of a plasma edge, i.e., there are no regions of sharply curved magnetic field lines anywhere in these discharges. The importance of this fact for stability is not yet fully investigated theoretically. As a third configuration a rectangular, flat pinch tube has been constructed, and the behaviour of a flat plasma sheet with edges is being studied experimentally

Application of stem-cell media to explant culture of human periosteum: An optimal approach for preparing osteogenic cell material.

Science.gov (United States)

Uematsu, Kohya; Nagata, Masaki; Kawase, Tomoyuki; Suzuki, Kenji; Takagi, Ritsuo

2013-01-01

As part of our clinical tests on bone regeneration using cultured periosteal sheets, here, we prepared cultured periosteal sheets in two types of stem-cell culture media, STK1 and STK3. Human periosteum was expanded either in 1% human serum-supplemented STK1 for 28 days, in 1% human serum-supplemented STK1 for 14 days followed by 1% human serum-supplemented STK3 for 14 days (1% human serum-supplemented STK1+3), or in 10% fetal bovine serum-supplemented Medium 199 for 28 days (control). Cultured periosteal sheet diameter and DNA content were significantly higher, and the multilayer structure was prominent in 1% human serum-supplemented STK1 and 1% human serum-supplemented STK1+3. The messenger RNA of osteoblastic markers was significantly upregulated in 1% human serum-supplemented STK1+3. Osteopontin-immunopositive staining and mineralization were evident across a wide area of the cultured periosteal sheet in 1% human serum-supplemented STK1+3. Subcutaneous implantation in nude mice following expansion in 1% human serum-supplemented STK1+3 produced the highest cultured periosteal sheet osteogenic activity. Expansion in 1% human serum-supplemented STK1+3 successfully induced cultured periosteal sheet growth while retaining osteogenic potential, and subsequent osteoblastic induction promoted the production of homogeneous cell material.

Effect of Cell Sheet Manipulation Techniques on the Expression of Collagen Type II and Stress Fiber Formation in Human Chondrocyte Sheets.

Science.gov (United States)

Wongin, Sopita; Waikakul, Saranatra; Chotiyarnwong, Pojchong; Siriwatwechakul, Wanwipa; Viravaidya-Pasuwat, Kwanchanok

2018-03-01

Cell sheet technology is applied to human articular chondrocytes to construct a tissue-like structure as an alternative treatment for cartilage defect. The effect of a gelatin manipulator, as a cell sheet transfer system, on the quality of the chondrocyte sheets was investigated. The changes of important chondrogenic markers and stress fibers, resulting from the cell sheet manipulation, were also studied. The chondrocyte cell sheets were constructed with patient-derived chondrocytes using a temperature-responsive polymer and a gelatin manipulator as a transfer carrier. The properties of the cell sheets, including sizes, expression levels of collagen type II and I, and the localization of the stress fibers, were assessed and compared with those of the cell sheets harvested without the gelatin manipulator. Using the gelatin manipulator, the original size of the chondrocyte cell sheets was retained with abundant stress fibers, but with a decrease in the expression of collagen type II. Without the gelatin manipulator, although the cell shrinkage occurred, the cell sheet with suppressed stress fiber formation showed significantly higher levels of collagen type II. These results support our observations that stress fiber formation in chondrocyte cell sheets affected the production of chondrogenic markers. These densely packed tissue-like structures possessed a good chondrogenic activity, indicating their potential for use in autologous chondrocyte implantation to treat cartilage defects.

FROM UNDERGRADUATE STUDENT TO PROFESSIONAL TEACHER. AN ASSESSMENT OF THE NDEA INSTITUTES FOR UNDERGRADUATES PREPARING TO BECOME ELEMENTARY OR SECONDARY TEACHERS OF MODERN FOREIGN LANGUAGES.

Science.gov (United States)

AXELROD, JOSEPH

A STUDY WAS MADE OF SEVEN NDEA INSTITUTES, GIVEN IN THE SUMMERS OF 1965 AND 1966 FOR UNDERGRADUATES PREPARING TO BE FOREIGN LANGUAGE TEACHERS, TO DETERMINE IF THESE INSTITUTES ARE AN EFFECTIVE SUPPLEMENT TO COLLEGE LANGUAGE PROGRAMS. INFORMATION SOURCES FOR THE STUDY WERE INSTITUTE DIRECTORS AND THEIR STAFF, VISITORS' OBSERVATIONS, AND…

Settlement during vibratory sheet piling

NARCIS (Netherlands)

Meijers, P.

2007-01-01

During vibratory sheet piling quite often the soil near the sheet pile wall will settle. In many cases this is not a problem. For situations with houses, pipelines, roads or railroads at relative short distance these settlements may not be acceptable. The purpose of the research described in this

49 CFR 1243.2 - Condensed balance sheet.

Science.gov (United States)

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Condensed balance sheet. 1243.2 Section 1243.2... § 1243.2 Condensed balance sheet. Commencing with reports for the 3 months beginning January 1, 1972, and... hereby, required to compile and file quarterly reports of balance sheet items in accordance with...

Electron energization in the geomagnetic tail current sheet

International Nuclear Information System (INIS)

Lyons, L.R.

1984-01-01

Electron motion in the distant tail current sheet is evaluated and found to violate the guiding center approximation at energies > or approx. =100 eV. Most electrons within the energy range approx.10 -1 -10 2 keV that enter the current sheet become trapped within the magnetic field reversal region. These electrons then convect earthward and gain energy from the cross-tail electric field. If the energy spectrum of electrons entering the current sheet is similar to that of electrons from the boundary layer surrounding the magnetotail, the energy gain from the electric field produces electron energy spectra comparable to those observed in the earth's plasma sheet. Thus current sheet interactions can be a significant source of particles and energy for plasma sheet electrons as well as for plasma sheet ions. A small fraction of electrons within the current sheet has its pitch angles scattered so as to be ejected from the current sheet within the atmospheric loss cone. These electrons can account for the electron precipitation near the high-latitude boundary of energetic electrons, which is approximately isotropic in pitch angle up to at least several hundred keV. Current sheet interaction should cause approximately isotropic auroral precipitation up to several hundred keV energies, which extends to significantly lower latitudes for ions than for electrons in agreement with low-altitude satellite observations. Electron precipitation associated with diffuse aurora generally has a transition at 1-10 keV to anisotropic pitch angle distributions. Such electron precipitation cannot be explained by current sheet interactions, but it can be explained by pitch angle diffusion driven by plasma turbulence

Bessel light sheet structured illumination microscopy

Science.gov (United States)

Noshirvani Allahabadi, Golchehr

Biomedical study researchers using animals to model disease and treatment need fast, deep, noninvasive, and inexpensive multi-channel imaging methods. Traditional fluorescence microscopy meets those criteria to an extent. Specifically, two-photon and confocal microscopy, the two most commonly used methods, are limited in penetration depth, cost, resolution, and field of view. In addition, two-photon microscopy has limited ability in multi-channel imaging. Light sheet microscopy, a fast developing 3D fluorescence imaging method, offers attractive advantages over traditional two-photon and confocal microscopy. Light sheet microscopy is much more applicable for in vivo 3D time-lapsed imaging, owing to its selective illumination of tissue layer, superior speed, low light exposure, high penetration depth, and low levels of photobleaching. However, standard light sheet microscopy using Gaussian beam excitation has two main disadvantages: 1) the field of view (FOV) of light sheet microscopy is limited by the depth of focus of the Gaussian beam. 2) Light-sheet images can be degraded by scattering, which limits the penetration of the excitation beam and blurs emission images in deep tissue layers. While two-sided sheet illumination, which doubles the field of view by illuminating the sample from opposite sides, offers a potential solution, the technique adds complexity and cost to the imaging system. We investigate a new technique to address these limitations: Bessel light sheet microscopy in combination with incoherent nonlinear Structured Illumination Microscopy (SIM). Results demonstrate that, at visible wavelengths, Bessel excitation penetrates up to 250 microns deep in the scattering media with single-side illumination. Bessel light sheet microscope achieves confocal level resolution at a lateral resolution of 0.3 micron and an axial resolution of 1 micron. Incoherent nonlinear SIM further reduces the diffused background in Bessel light sheet images, resulting in

Magnetic configurations of the tilted current sheets in magnetotail

Directory of Open Access Journals (Sweden)

C. Shen

2008-11-01

Full Text Available In this research, the geometrical structures of tilted current sheet and tail flapping waves have been analysed based on multiple spacecraft measurements and some features of the tilted current sheets have been made clear for the first time. The geometrical features of the tilted current sheet revealed in this investigation are as follows: (1 The magnetic field lines (MFLs in the tilted current sheet are generally plane curves and the osculating planes in which the MFLs lie are about vertical to the equatorial plane, while the normal of the tilted current sheet leans severely to the dawn or dusk side. (2 The tilted current sheet may become very thin, the half thickness of its neutral sheet is generally much less than the minimum radius of the curvature of the MFLs. (3 In the neutral sheet, the field-aligned current density becomes very large and has a maximum value at the center of the current sheet. (4 In some cases, the current density is a bifurcated one, and the two humps of the current density often superpose two peaks in the gradient of magnetic strength, indicating that the magnetic gradient drift current is possibly responsible for the formation of the two humps of the current density in some tilted current sheets. Tilted current sheets often appear along with tail current sheet flapping waves. It is found that, in the tail flapping current sheets, the minimum curvature radius of the MFLs in the current sheet is rather large with values around 1 RE, while the neutral sheet may be very thin, with its half thickness being several tenths of RE. During the flapping waves, the current sheet is tilted substantially, and the maximum tilt angle is generally larger than 45°. The phase velocities of these flapping waves are several tens km/s, while their periods and wavelengths are several tens of minutes, and several earth radii, respectively. These tail flapping events generally last several hours and occur during quiet periods or periods of

Sports Supplements

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Sports Supplements KidsHealth / For Teens / Sports Supplements What's in ... really work? And are they safe? What Are Sports Supplements? Sports supplements (also called ergogenic aids ) are ...

Relativistic current sheets in electron-positron plasmas

International Nuclear Information System (INIS)

Zenitani, S.

2008-01-01

The current sheet structure with magnetic field reversal is one of the fundamental structure in space and astrophysical plasmas. It draws recent attention in high-energy astrophysical settings, where relativistic electron-positron plasmas are considered. In this talk we will review the recent progress of the physical processes in the relativistic current sheet. The kinetic stability of a single current sheet, the nonlinear behavior of these instabilities, and recent challenges on the multi current sheet systems are introduced. We will also introduce some problems of magnetic reconnection in these relativistic environments. (author)

Tube sheet design for PFBR steam generator

International Nuclear Information System (INIS)

Chellapandi, P.; Chetal, S.C.; Bhoje, S.B.

1991-01-01

Top and bottom tube sheets of PFBR Steam Generators have been analysed with 3D and axisymmetric models using CASTEM Programs. Analysis indicates that the effects of piping reactions at the inlet/outlet nozzles on the primary stresses in the tube sheets are negligible and the asymmetricity of the deformation pattern introduced in the tube sheet by the presence of inlet/outlet and manhole nozzles is insignificant. The minimum tube sheet thicknesses for evaporator and reheater are 135 mm and 75 mm respectively. Further analysis has indicated the minimum fillet radius at the junction of tube sheet and dished end should be 20 mm. Simplified methodology has been developed to arrive at the number of thermal baffles required to protect the tube sheet against fatigue damage due to thermal transient. This method has been applied to PFBR steam generators to determine the required number of thermal baffles. For protecting the bottom tube sheet of evaporator against the thermal shock due to feed water and secondary pump trip, one thermal shield is found to be sufficient. Further analysis is required to decide upon the actual number to take care of the severe thermal transient, following the event of sudden dumping of water/steam, immediately after the sodium-water reaction. (author)

17 CFR 210.5-02 - Balance sheets.

Science.gov (United States)

2010-04-01

... customers at the date of the balance sheet. Include a general description of the prerequisites for billing... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Balance sheets. 210.5-02... Balance sheets. The purpose of this rule is to indicate the various line items and certain additional...

Pressure balance between lobe and plasma sheet

International Nuclear Information System (INIS)

Baumjohann, W.; Paschmann, G.; Luehr, H.

1990-01-01

Using eight months of AMPTE/IRM plasma and magnetic field data, the authors have done a statistical survey on the balance of total (thermal and magnetic) pressure in the Earth's plasma sheet and tail lobe. About 300,000 measurements obtained in the plasma sheet and the lobe were compared for different levels of magnetic activity as well as different distances from the Earth. The data show that lobe and plasma sheet pressure balance very well. Even in the worst case they do not deviate by more than half of the variance in the data itself. Approximately constant total pressure was also seen during a quiet time pass when IRM traversed nearly the whole magnetotail in the vertical direction, from the southern hemisphere lobe through the neutral sheet and into the northern plasma sheet boundary layer

Thermomechanical processing of plasma sprayed intermetallic sheets

Science.gov (United States)

Hajaligol, Mohammad R.; Scorey, Clive; Sikka, Vinod K.; Deevi, Seetharama C.; Fleischhauer, Grier; Lilly, Jr., A. Clifton; German, Randall M.

2001-01-01

A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3% Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

17 CFR 210.7-03 - Balance sheets.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Balance sheets. 210.7-03... 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Insurance Companies § 210.7-03 Balance sheets. (a... otherwise permitted by the Commission, should appear on the face of the balance sheets and in the notes...

Disposal sheet for preventing scattering of radioactive contaminated material

International Nuclear Information System (INIS)

Miyasaka, Shun-ichi; Kurioka, Hitoshi; Nakamura, Kenjiro.

1990-01-01

Upon disposal of vinyl sheets at the final stage of dismantling operation for nuclear buildings, etc., radioactive contaminated materials caused by cutting concretes, etc. remain on the sheets. In view of the above, members capable of restoring original shape due to the temperature difference are attached to the sheet main body so that the sheet main body may be folded into a bag-like shape. Since the members as described above are bent upon temperature elevation in the sheets, the sheet main body is pulled by the members and then spontaneously folded into a bag-like shape. As a result, the radioactive contaminated materials remaining on the sheets are wrapped into the sheet main body free from touch to operator's hands or without scattering to the surrounding. This can prevent operator's external and internal exposure. (T.M.)

Single Point Incremental Forming using a Dummy Sheet

DEFF Research Database (Denmark)

Skjødt, Martin; Silva, Beatriz; Bay, Niels

2007-01-01

A new version of single point incremental forming (SPIF) is presented. This version includes a dummy sheet on top of the work piece, thus forming two sheets instead of one. The dummy sheet, which is in contact with the rotating tool pin, is discarded after forming. The new set-up influences....... The possible influence of friction between the two sheets is furthermore investigated. The results show that the use of a dummy sheet reduces wear of the work piece to almost zero, but also causes a decrease in formability. Bulging of the planar sides of the pyramid is reduced and surface roughness...

The Development of Professional Mobility of Teachers in Supplemental Education System

Science.gov (United States)

Valeeva, Roza A.; Amirova, Lyudmila A.

2016-01-01

Actual continuity of the problems stated in this article caused by the fact that modern education is directed at the formation of a mobile person of the teacher, who is able to transform the educational reality and himself in accordance with the requirements of a developing society, and to provide not only high-quality mastering studying the…

Neutron spatial distribution measurement with 6Li-contained thermoluminescent sheets

International Nuclear Information System (INIS)

Konnai, A.; Odano, N.; Sawamura, H.; Ozasa, N.; Ishikawa, Y.

2006-01-01

We have been developing a thermoluminescent (TL) sheet for photon dosimetry (TL sheet) with thermoluminescent material of LiF:Mg, Cu, P and a co-polymer of ethylene and tetrafluoroethylene. For the purpose of a development of simple method for neutron spatial distribution measurement, TL sheet for neutron detection (NTL sheet) is made by adding 94.7% enriched 6 LiF to TL sheet. TL material in TL sheet is directly excited by ionizing radiation whereas, in the case of neutron detection, TL material in NTL sheet is indirectly excited by neutron capture reaction. That is neutron distribution can be obtained with TL caused by α particle from 6 Li(n, α) 3 H reaction. Responses of NTL sheets to neutrons were examined at the neutron beam irradiation facility for Boron Neutron Capture Therapy (BNCT) in JRR-4 research reactor in Japan Atomic Energy Agency. TL and NTL sheets were exposed to striped and roundly distributed neutron fields. Attenuations of neutron flux in air and water were also observed using NTL sheets. TL sheets were also exposed on the same conditions and compared with NTL sheets. TL intensity ratios of NTL sheet to TL sheet were consistent with the calculated value from 6 Li content. Thermal neutron attenuation observed by NTL sheet also corresponded with the result measured by Au wire radioactivation and TLD chips, which were currently used in BNCT at JRR-4. These results were analyzed with by Monte Carlo simulation. The present results indicated that NTL sheet is applicable to measurement of neutron spatial distribution. (author)

The Influence of Teachers' Conceptions on Their Students' Learning: Children's Understanding of Sheet Music

Science.gov (United States)

López-Íñiguez, Guadalupe; Pozo, Juan Ignacio

2014-01-01

Background: Despite increasing interest in teachers' and students' conceptions of learning and teaching, and how they influence their practice, there are few studies testing the influence of teachers' conceptions on their students' learning. Aims: This study tests how teaching conception (TC; with a distinction between…

Teacher-Guided Interactive Multimedia for Teaching English in an EFL Context

Science.gov (United States)

Tsai, Roland; Jenks, Michael

2009-01-01

This quasi-experimental study explored the effect of a "Teacher Guided Multimedia" CD-ROM program as a supplement in teaching vocabulary acquisition to EFL students. Eighty seven juniors in the Food and Beverage Management Department at Yuanpei University in northern Taiwan participated in the study. Students from two intact classes were…

On the possible eigenoscillations of neutral sheets

International Nuclear Information System (INIS)

Almeida, W.A.; Costa, J.M. da; Aruquipa, E.G.; Sudano, J.P.

1974-12-01

A neutral sheet model with hyperbolic tangent equilibrium magnetic field and hyperbolic square secant density profiles is considered. It is shown that the equation for small oscillations takes the form of an eigenvalue oscillation problem. Computed eigenfrequencies of the geomagnetic neutral sheet were found to be in the range of the resonant frequencies of the geomagnetic plasma sheet computed by other authors

Uranium mining sites - Thematic sheets

International Nuclear Information System (INIS)

2009-01-01

A first sheet proposes comments, data and key numbers about uranium extraction in France: general overview of uranium mining sites, status of waste rock and tailings after exploitation, site rehabilitation. The second sheet addresses the sources of exposure to ionizing radiations due to ancient uranium mining sites: discussion on the identification of these sources associated with these sites, properly due to mining activities or to tailings, or due to the transfer of radioactive substances towards water and to the contamination of sediments, description of the practice and assessment of radiological control of mining sites. A third sheet addresses the radiological exposure of public to waste rocks, and the dose assessment according to exposure scenarios: main exposure ways to be considered, studied exposure scenarios (passage on backfilled path and grounds, stay in buildings built on waste rocks, keeping mineralogical samples at home). The fourth sheet addresses research programmes of the IRSN on uranium and radon: epidemiological studies (performed on mine workers; on French and on European cohorts, French and European studies on the risk of lung cancer associated with radon in housing), study of the biological effects of chronic exposures. The last sheet addresses studies and expertises performed by the IRSN on ancient uranium mining sites in France: studies commissioned by public authorities, radioactivity control studies performed by the IRSN about mining sites, participation of the IRSN to actions to promote openness to civil society

Sheet, ligament and droplet formation in swirling primary atomization

Directory of Open Access Journals (Sweden)

Changxiao Shao

2018-04-01

Full Text Available We report direct numerical simulations of swirling liquid atomization to understand the physical mechanism underlying the sheet breakup of a non-turbulent liquid swirling jet which lacks in-depth investigation. The volume-of-fluid (VOF method coupled with adapted mesh refinement (AMR technique in GERRIS code is employed in the present simulation. The mechanisms of sheet, ligament and droplet formation are investigated. It is observed that the olive-shape sheet structure is similar to the experimental result qualitatively. The numerical results show that surface tension, pressure difference and swirling effect contribute to the contraction and extension of liquid sheet. The ligament formation is partially at the sheet rim or attributed to the extension of liquid hole. Especially, the movement of hairpin vortex exerts by an anti-radial direction force to the sheet surface and leads to the sheet thinness. In addition, droplet formation is attributed to breakup of ligament and central sheet.

Sheet, ligament and droplet formation in swirling primary atomization

Science.gov (United States)

Shao, Changxiao; Luo, Kun; Chai, Min; Fan, Jianren

2018-04-01

We report direct numerical simulations of swirling liquid atomization to understand the physical mechanism underlying the sheet breakup of a non-turbulent liquid swirling jet which lacks in-depth investigation. The volume-of-fluid (VOF) method coupled with adapted mesh refinement (AMR) technique in GERRIS code is employed in the present simulation. The mechanisms of sheet, ligament and droplet formation are investigated. It is observed that the olive-shape sheet structure is similar to the experimental result qualitatively. The numerical results show that surface tension, pressure difference and swirling effect contribute to the contraction and extension of liquid sheet. The ligament formation is partially at the sheet rim or attributed to the extension of liquid hole. Especially, the movement of hairpin vortex exerts by an anti-radial direction force to the sheet surface and leads to the sheet thinness. In addition, droplet formation is attributed to breakup of ligament and central sheet.

Copper contamination in thin stainless steel sheet

International Nuclear Information System (INIS)

Holbert, R.K. Jr.; Dobbins, A.G.; Bennett, R.K. Jr.

1986-01-01

The standard welding technique used at Oak Ridge Y-12 Plant for joining thin stainless sheet is the gas tungsten arc (GTA) welding process. One of the reoccurring problems with the sheet welds is surface cracking in the heat-affected zone (HAZ). Metallography shows that the cracks are only about 0.05 mm (0.002 in.) deep which is significant in a 0.25 mm (0.01 in.) thick sheet. Thus, welding requirements do not permit any surfacing cracking as detected by a fluorescent dye penetrant test conducted on every part after welding. Surface cracks have been found in both of the two most common weld designs in the thin sheet fabricated at the Oak Ridge Y-12 Plant. These butt joints are welded between two 0.25 mm thick stainless steel sheets and a tube with eyelet welded to a 25 mm (0.98 in.) thick sheet. The weld between the two sheets is made on a semiautomatic seam welding unit, whereas the tube-to-eyelet-to-sheet welds are done manually. The quality of both welds is very dependent on the welding procedure and the way the parts are placed in the weld fixturing. Metallographic examination has indicated that some welded parts with surface cracking in the weld region had copper particles on the surface, and the question of copper contamination has been raised. With the aid of a scanning electron microscope and an electron microprobe, the existence of copper in an around the surface cracks has been verified. The copper is on the surface of the parts prior to welding in the form of small dust particles

World-sheet gauge fields in superstrings

International Nuclear Information System (INIS)

Porrati, M.; Tomboulis, E.T.

1989-01-01

We investigate the introduction of world-sheet 2-dimensional gauge fields in a manner consistent with world-sheet supersymmetry. We obtain the effective string action resulting from the exact integration over the world-sheet gauge fields to show that it generally describes string models with spontaneous breaking of gauge symmetries with continuous breaking parameters. We examine the question of spacetime supersymmetry spontaneous breaking, and show that breaking with continuous, in particular arbitrarily small breaking parameters does not occur; only breaking for discrete values of parameters is possible. (orig.)

Bifurcation of Jovian magnetotail current sheet

Directory of Open Access Journals (Sweden)

P. L. Israelevich

2006-07-01

Full Text Available Multiple crossings of the magnetotail current sheet by a single spacecraft give the possibility to distinguish between two types of electric current density distribution: single-peaked (Harris type current layer and double-peaked (bifurcated current sheet. Magnetic field measurements in the Jovian magnetic tail by Voyager-2 reveal bifurcation of the tail current sheet. The electric current density possesses a minimum at the point of the Bx-component reversal and two maxima at the distance where the magnetic field strength reaches 50% of its value in the tail lobe.

Determinants of dietary supplement use--healthy individuals use dietary supplements.

Science.gov (United States)

Kofoed, Christina L F; Christensen, Jane; Dragsted, Lars O; Tjønneland, Anne; Roswall, Nina

2015-06-28

The prevalence of dietary supplement use varies largely among populations, and previous studies have indicated that it is high in the Danish population compared with other European countries. The diversity in supplement use across countries indicates that cultural and environmental factors could influence the use of dietary supplements. Only few studies investigating the use of dietary supplements have been conducted in the Danish population. The present cross-sectional study is based on 54,948 Danes, aged 50-64 years, who completed self-administrated questionnaires on diet, dietary supplements and lifestyle between 1993 and 1997. A health index including smoking, physical activity, alcohol and diet, and a metabolic risk index including waist circumference, urinary glucose and measured hypertension were constructed. Logistic regression was used to investigate these determinants in relation to the intake of dietary supplements. We found that 71 % of the participants were dietary supplement users; female sex, older age groups and higher educated participants were more likely to be users of any dietary supplements. One additional point in the health index was associated with 19, 16 and 9 % higher likelihood of being user of any, more common and less common supplements, respectively. In the metabolic risk index, one additional point was associated with 17 and 16 % lower likelihood of being user of any supplement and more common supplements, respectively. No significant association was found for less common supplement use. In conclusion, those with the healthiest lifestyle were more likely to use dietary supplements. Thus, lifestyle and dietary composition should be considered as confounders on supplement use and health outcomes.

Over the counter drugs (and dietary supplement) exercise: a team-based introduction to biochemistry for health professional students.

Science.gov (United States)

Phadtare, Sangita; Abali, Emine; Brodsky, Barbara

2013-01-01

For successful delivery of basic science topics for health-professional students, it is critical to reduce apprehension and illustrate relevance to clinical settings and everyday life. At the beginning of the Biochemistry course for Physician Assistants, a team-based assignment was designed to develop an understanding of the mechanism of action, effectiveness, and toxicity of five common over the counter (OTC) drugs and dietary supplements, and place these familiar medicines in a political and historical context. The objectives of this exercise were to stimulate interest in biochemistry; to provide basic information on enzymes and enzyme inhibitors related to these drugs to be expanded upon later in the course; and to encourage active and interactive learning. Teams of five students were formed, and each student was given an information sheet on aspirin, alpha-galactosidase, orlistat, dextromethorphan, or simvastatin, a low dose statin, which was previously available without prescription at pharmacies in the UK. After each member of the team acquired information on one OTC drug/dietary supplement by reading an assigned information sheet, the team was asked to go through a series of questions, and then submit answers to a quiz as a group. A high rate of success on the quiz, an overwhelmingly positive response on formal course evaluations, and enthusiastic exchanges during class suggested this team-based session accomplished its goals. Copyright © 2013 Wiley-Liss, Inc.

Environmental constraints on West Antarctic ice-sheet formation

Energy Technology Data Exchange (ETDEWEB)

Lindstrom, D R; MacAyeal, D R

1987-01-01

Small perturbations in Antarctic environmental conditions can culminate in the demise of the Antarctic ice sheet's western sector. This may have happened during the last interglacial period, and could recur within the next millennium due to atmospheric warming from trace gas and CO/sub 2/ increases. In this study, we investigate the importance of sea-level, accumulation rate, and ice influx from the East Antarctic ice sheet in the re-establishment of the West Antarctic ice sheet from a thin cover using a time-dependent numerical ice-shelf model. Our results show that a precursor to the West Antarctic ice sheet can form within 3000 years. Sea-level lowering caused by ice-sheet development in the Northern Hemisphere has the greatest environmental influence. Under favorable conditions, ice grounding occurs over all parts of the West Antarctic ice sheet except up-stream of Thwaites Glacier and in the Ross Sea region.

From a Distance: Student Empowerment and Constructing Teacher Identities Online

Directory of Open Access Journals (Sweden)

Ayshe TALAY-ONGAN

2004-07-01

Full Text Available ABSTRACT Online learning has infiltrated tertiary learning and teaching applications and offers enrichment in the construction of student learning through opportunities unfathomable for most university teachers when they were students. While all students benefit from online learning components that are supplemental to more traditional modes of teaching, it is the distance education students who are the most significant beneficiaries of these applications. This paper presents a framework developed towards ongoing dynamic evaluations of undergraduate units that are fully online on the WebCT platform in one of Australia's leading early childhood teacher education programs. It also describes a journey in which online learning and teaching experiences harnessed technology to better suit pedagogically-driven innovations and initiatives through unit content, instructional design and the emotionally supportive and empowering 'community spirit' created through online communications for distance education students. These experiences helped shape a platform of social discourse in constructing complex professional identities of pre-service early childhood teachers, and one of their teachers.

Hydrothermal growth of upright-standing ZnO sheet microcrystals

International Nuclear Information System (INIS)

Shi, Ruixia; Yang, Ping; Dong, Xiaobin; Jia, Changchao; Li, Jia

2014-01-01

Highlights: • Upright-standing ZnO sheet microcrystals were hydrothermally fabricated. • The ZnO sheets were prepared with sodium oxalate at 70 °C without any surfactant. • The preferable adsorption of oxalate anions causes the formation of ZnO sheet. • The continuous growth in six directions leads to the formation of hexagonal sheets. - Abstract: Large-scale upright-standing ZnO sheet microcrystals were fabricated on Zn substrate using sodium oxalate as structure-directing agent by a hydrothermal method at low temperature (70 °C) without any surfactant. The sheets are about 3–5 μm in dimension and 100–300 nm in thickness. The strong and narrow diffraction peaks of ZnO indicate that the sample has a good crystallinity and size. The morphology of sheet-like ZnO varied with the concentrations of sodium oxalate and reaction time. The sheet-like ZnO would transform into rod-like ones when sodium oxalate was substituted by equivalent sodium acetate. The formation of sheet-like ZnO is attributed to the preferable adsorption of oxalate anions on (0 0 0 1) face of ZnO, which inhibits the intrinsic growth of ZnO. Additionally, the continuous growth in six (0 1 −1 0) directions that have the lowest surface energy leads to the formation of hexagonal sheets

Diversified Professionalism of Physical Education Teachers in the Asian Context of Hong Kong

Science.gov (United States)

Sum, Raymond Kim Wai; Dimmock, Clive

2014-01-01

This study investigates the socialization and professional experiences of primary school physical education teachers (PSPETs) in the Asian context of Hong Kong. A qualitative research design is adopted. The researcher used semi-structured interviews, supplemented by documentary sources (diaries) for conducting data collection. Eleven PSPETs…

12 CFR 615.5211 - Risk categories-balance sheet assets.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Risk categories-balance sheet assets. 615.5211...—balance sheet assets. Section 615.5210(c) specifies certain balance sheet assets that are not assigned to the risk categories set forth below. All other balance sheet assets are assigned to the percentage...

The plasma sheet boundary and Ksub(p)

International Nuclear Information System (INIS)

Freeman, J.W.

1975-01-01

Freeman and Maguire (1967) first drew attention to the intrusion of energetic plasma from the tail to the geostationary orbit during geomagnetically disturbed times. Vasyliunas (1968) reported a correlation between the inward extension of the inner boundary of the plasma sheet and the Ksub(p) index and pointed out that the plasma sheet could occasionally reach the geostationary orbit distance. More recently McIlwain (1972) using the more refined detectors aboard the ATS-5 geostationary space-craft, has emphasized the correlation between the location of the plasma sheet boundary along the ATS orbit and geomagnetic activity. Using some older but unpublished data from the Suprathermal Ion Detector aboard the ATS-1 geostationary satellite, the relation between the local time occurrence of the plasma sheet at the geostationary orbit (6.6Rsub(E)) and Ksub(p) index is reported and then a relationship for the shift in the plasma sheet radial position is derived. (Auth.)

Surface elevation changes of the greenland ice sheet - results from ESA'S ice sheet CCI

DEFF Research Database (Denmark)

Fredenslund Levinsen, Joanna; Khvorostovky, Kirill; Meister, Rakia

2013-01-01

In order to ensure long-term climate data records for the Greenland Ice Sheet (GIS), ESA have launched the Climate Change Initiative (CCI). This work presents the preliminary steps towards the Ice Sheet CCI's surface elevation change (SEC) derivation using radar altimeter data. In order to find...... the most optimal method, a Round Robin exercise was conducted in which the scientific community was asked to provide their best SEC estimate over the Jakobshavn Isbr drainage basin. The participants used both repeat-track (RT), overlapping footprints, and the cross-over (XO) methods, and both ICESat laser...... and Envisat radar altimeter data were used. Based on this and feedback sheets describing their methods we found that a combination of the RT and XO techniques yielded the best results. In the following, the obtained results will be presented and discussed....

Probability based hydrologic catchments of the Greenland Ice Sheet

Science.gov (United States)

Hudson, B. D.

2015-12-01

Greenland Ice Sheet melt water impacts ice sheet flow dynamics, fjord and coastal circulation, and sediment and biogeochemical fluxes. Melt water exiting the ice sheet also is a key term in its mass balance. Because of this, knowledge of the area of the ice sheet that contributes melt water to a given outlet (its hydrologic catchment) is important to many ice sheet studies and is especially critical to methods using river runoff to assess ice sheet mass balance. Yet uncertainty in delineating ice sheet hydrologic catchments is a problem that is rarely acknowledged. Ice sheet catchments are delineated as a function of both basal and surface topography. While surface topography is well known, basal topography is less certain because it is dependent on radar surveys. Here, I a present a Monte Carlo based approach to delineating ice sheet catchments that quantifies the impact of uncertain basal topography. In this scheme, over many iterations I randomly vary the ice sheet bed elevation within published error bounds (using Morlighem et al., 2014 bed and bed error datasets). For each iteration of ice sheet bed elevation, I calculate the hydraulic potentiometric surface and route water over its path of 'steepest' descent to delineate the catchment. I then use all realizations of the catchment to arrive at a probability map of all major melt water outlets in Greenland. I often find that catchment size is uncertain, with small, random perturbations in basal topography leading to large variations in catchments size. While some catchments are well defined, others can double or halve in size within published basal topography error bars. While some uncertainty will likely always remain, this work points to locations where studies of ice sheet hydrology would be the most successful, allows reinterpretation of past results, and points to where future radar surveys would be most advantageous.

On the balance of stresses in the plasma sheet.

Science.gov (United States)

Rich, F. J.; Wolf, R. A.; Vasyliunas, V. M.

1972-01-01

The stress resulting from magnetic tension on the neutral sheet must, in a steady state, be balanced by any one or a combination of (1) a pressure gradient in the direction along the axis of the tail, (2) a similar gradient of plasma flow kinetic energy, and (3) the tension resulting from a pressure anisotropy within the plasma sheet. Stress balance in the first two cases requires that the ratios h/LX and BZ/BX be of the same order of magnitude, where h is the half-thickness of the neutral sheet, LX is the length scale for variations along the axis of the tail, and BZ and BX are the magnetic field components in the plasma sheet just outside the neutral sheet. The second case requires, in addition, that the plasma flow speed within the neutral sheet be of the order of or larger than the Alfven speed outside the neutral sheet. Stress balance in the third case requires that just outside the neutral sheet the plasma pressure obey the marginal firehose stability condition.

Thermal Transport Properties of Dry Spun Carbon Nanotube Sheets

Directory of Open Access Journals (Sweden)

Heath E. Misak

2016-01-01

Full Text Available The thermal properties of carbon nanotube- (CNT- sheet were explored and compared to copper in this study. The CNT-sheet was made from dry spinning CNTs into a nonwoven sheet. This nonwoven CNT-sheet has anisotropic properties in in-plane and out-of-plane directions. The in-plane direction has much higher thermal conductivity than the out-of-plane direction. The in-plane thermal conductivity was found by thermal flash analysis, and the out-of-plane thermal conductivity was found by a hot disk method. The thermal irradiative properties were examined and compared to thermal transport theory. The CNT-sheet was heated in the vacuum and the temperature was measured with an IR Camera. The heat flux of CNT-sheet was compared to that of copper, and it was found that the CNT-sheet has significantly higher specific heat transfer properties compared to those of copper. CNT-sheet is a potential candidate to replace copper in thermal transport applications where weight is a primary concern such as in the automobile, aircraft, and space industries.

Nonparaxial Bessel and Bessel–Gauss pincers light-sheets

Energy Technology Data Exchange (ETDEWEB)

Mitri, F.G., E-mail: F.G.Mitri@ieee.org

2017-01-23

Highlights: • Bessel and Bessel–Gauss autofocusing light sheets (i.e. beams in 2D) are developed. • The light-sheets are synthesized based on the angular spectrum decomposition method. • Computations of the scattering, radiation force and torque benefit from the solutions. - Abstract: Nonparaxial optical Bessel and Bessel–Gauss pincers optical-sheets are introduced based upon the angular spectrum decomposition in plane waves. The angular spectrum function and the beam-shape coefficients are expressed by means of improper integrals computed numerically. The radiated component of the electric field is also evaluated, displaying unique features of the nonparaxial Bessel pincers light-sheets. This new type of auto-focusing light-sheets finds potential applications in the development of novel methods in optical light-sheet tweezers for particle manipulation in opto-fluidics, particle sizing and imaging. Numerical predictions for the scattering, radiation force and torque, and particle dynamics also benefit from the developed beam solution.

Nonparaxial Bessel and Bessel–Gauss pincers light-sheets

International Nuclear Information System (INIS)

Mitri, F.G.

2017-01-01

Highlights: • Bessel and Bessel–Gauss autofocusing light sheets (i.e. beams in 2D) are developed. • The light-sheets are synthesized based on the angular spectrum decomposition method. • Computations of the scattering, radiation force and torque benefit from the solutions. - Abstract: Nonparaxial optical Bessel and Bessel–Gauss pincers optical-sheets are introduced based upon the angular spectrum decomposition in plane waves. The angular spectrum function and the beam-shape coefficients are expressed by means of improper integrals computed numerically. The radiated component of the electric field is also evaluated, displaying unique features of the nonparaxial Bessel pincers light-sheets. This new type of auto-focusing light-sheets finds potential applications in the development of novel methods in optical light-sheet tweezers for particle manipulation in opto-fluidics, particle sizing and imaging. Numerical predictions for the scattering, radiation force and torque, and particle dynamics also benefit from the developed beam solution.

Bifurcation of Jovian magnetotail current sheet

Directory of Open Access Journals (Sweden)

P. L. Israelevich

2006-07-01

Full Text Available Multiple crossings of the magnetotail current sheet by a single spacecraft give the possibility to distinguish between two types of electric current density distribution: single-peaked (Harris type current layer and double-peaked (bifurcated current sheet. Magnetic field measurements in the Jovian magnetic tail by Voyager-2 reveal bifurcation of the tail current sheet. The electric current density possesses a minimum at the point of the B_x-component reversal and two maxima at the distance where the magnetic field strength reaches 50% of its value in the tail lobe.

Potential of Using iPad as a Supplement to Teach Math to Students with Learning Disabilities

Science.gov (United States)

Kaur, Daljit; Koval, Ashely; Chaney, Hannah

2017-01-01

This qualitative study was conducted to identify the potential of using iPad as a supplement to teach math to students with learning disabilities. Ten teacher candidates from a university in the south provided one-on-one math tutoring services to ten students in a self-contained classroom at a local high poverty elementary school. The students…

Buckling Behavior of Substrate Supported Graphene Sheets

Directory of Open Access Journals (Sweden)

Kuijian Yang

2016-01-01

Full Text Available The buckling of graphene sheets on substrates can significantly degrade their performance in materials and devices. Therefore, a systematic investigation on the buckling behavior of monolayer graphene sheet/substrate systems is carried out in this paper by both molecular mechanics simulations and theoretical analysis. From 70 simulation cases of simple-supported graphene sheets with different sizes under uniaxial compression, two different buckling modes are investigated and revealed to be dominated by the graphene size. Especially, for graphene sheets with length larger than 3 nm and width larger than 1.1 nm, the buckling mode depends only on the length/width ratio. Besides, it is revealed that the existence of graphene substrate can increase the critical buckling stress and strain to 4.39 N/m and 1.58%, respectively, which are about 10 times those for free-standing graphene sheets. Moreover, for graphene sheets with common size (longer than 20 nm, both theoretical and simulation results show that the critical buckling stress and strain are dominated only by the adhesive interactions with substrate and independent of the graphene size. Results in this work provide valuable insight and guidelines for the design and application of graphene-derived materials and nano-electromechanical systems.

Teacher Leadership: Everyday Practices Surrounding Work- Related Stress

Directory of Open Access Journals (Sweden)

Chiweshe Nigel

2015-06-01

Full Text Available This interpretivist study contributes to our scholarly understanding of how everyday practices surrounding work-related stress in education affect teacher leadership and successful learning outcomes. Insights are drawn from our long-standing engagement in the field where we observed how teaching staff, students, and management interacted. These observations were supplemented by in-depth interviews with 20 teaching staff. Our findings reveal competing demands and practices across the individual intrapersonal environment and the work related environment. There were three key themes that emerged in answer to the core research question: 1 the role of relational practices in managing teacher burnout, 2 the role of surveillance practices in education and 3 the role of assimilating practices in education. Drawing insights from these practices, we develop a conceptual framework that will help us to see relations at work anew, and develop a deeper understanding of ‘sickies’, motivation, learning outcomes and teacher leadership opportunities in education

Lateral dimension-dependent antibacterial activity of graphene oxide sheets.

Science.gov (United States)

Liu, Shaobin; Hu, Ming; Zeng, Tingying Helen; Wu, Ran; Jiang, Rongrong; Wei, Jun; Wang, Liang; Kong, Jing; Chen, Yuan

2012-08-21

Graphene oxide (GO) is a promising precursor to produce graphene-family nanomaterials for various applications. Their potential health and environmental impacts need a good understanding of their cellular interactions. Many factors may influence their biological interactions with cells, and the lateral dimension of GO sheets is one of the most relevant material properties. In this study, a model bacterium, Escherichia coli ( E. coli ), was used to evaluate the antibacterial activity of well-dispersed GO sheets, whose lateral size differs by more than 100 times. Our results show that the antibacterial activity of GO sheets toward E. coli cells is lateral size dependent. Larger GO sheets show stronger antibacterial activity than do smaller ones, and they have different time- and concentration-dependent antibacterial activities. Large GO sheets lead to most cell loss after 1 h incubation, and their concentration strongly influences antibacterial activity at relative low concentration (oxidation capacity toward glutathione is similar, consistent with X-ray photoelectron spectroscopy and ultraviolet-visible absorption spectroscopy results. This suggests the lateral size-dependent antibacterial activity of GO sheets is caused by neither their aggregation states, nor oxidation capacity. Atomic force microscope analysis of GO sheets and cells shows that GO sheets interact strongly with cells. Large GO sheets more easily cover cells, and cells cannot proliferate once fully covered, resulting in the cell viability loss observed in the followed colony counting test. In contrast, small GO sheets adhere to the bacterial surfaces, which cannot effectively isolate cells from environment. This study highlights the importance of tailoring the lateral dimension of GO sheets to optimize the application potential with minimal risks for environmental health and safety.

Fabrication of Carbon Nanotube Polymer Actuator Using Nanofiber Sheet

Science.gov (United States)

Kato, Hayato; Shimizu, Akikazu; Sato, Taiga; Kushida, Masahito

2017-11-01

Carbon nanotube polymer actuators were developed using composite nanofiber sheets fabricated by multi-walled carbon nanotubes(MWCNTs) and poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). Nanofiber sheets were fabricated by electrospinning method. The effect of flow rate and polymer concentration on nanofiber formation were verified for optimum condition for fabricating nanofiber sheets. We examined the properties of MWCNT/PVDF-HFP nanofiber sheets, as follows. Electrical conductivity and mechanical strength increased as the MWCNT weight ratio increased. We fabricated carbon nanotube polymer actuators using MWCNT/PVDF-HFP nanofiber sheets and succeeded in operating of our actuators.

Global ice sheet/RSL simulations using the higher-order Ice Sheet System Model.

Science.gov (United States)

Larour, E. Y.; Ivins, E. R.; Adhikari, S.; Schlegel, N.; Seroussi, H. L.; Morlighem, M.

2017-12-01

Relative sea-level rise is driven by processes that are intimately linked to the evolution ofglacial areas and ice sheets in particular. So far, most Earth System models capable of projecting theevolution of RSL on decadal to centennial time scales have relied on offline interactions between RSL andice sheets. In particular, grounding line and calving front dynamics have not been modeled in a way that istightly coupled with Elasto-Static Adjustment (ESA) and/or Glacial-Isostatic Adjustment (GIA). Here, we presenta new simulation of the entire Earth System in which both Greenland and Antarctica ice sheets are tightly coupledto an RSL model that includes both ESA and GIA at resolutions and time scales compatible with processes suchas grounding line dynamics for Antarctica ice shelves and calving front dynamics for Greenland marine-terminatingglaciers. The simulations rely on the Ice Sheet System Model (ISSM) and show the impact of higher-orderice flow dynamics and coupling feedbacks between ice flow and RSL. We quantify the exact impact of ESA andGIA inclusion on grounding line evolution for large ice shelves such as the Ronne and Ross ice shelves, as well asthe Agasea Embayment ice streams, and demonstate how offline vs online RSL simulations diverge in the long run,and the consequences for predictions of sea-level rise.This work was performed at the California Institute of Technology's Jet Propulsion Laboratory undera contract with the National Aeronautics and Space Administration's Cryosphere Science Program.

Teacher's Guide to Accompany "Artes Latinae," the Encyclopaedia Britannica Latin Instructional System.

Science.gov (United States)

Masciantonio, Rudolph; And Others

This guide, a supplement to the "Artes Latinae Level One Teacher's Manual," prepared for use in the School District of Philadelphia, focuses primarily on how to adapt this course, intended for individualized instruction, to group instruction. Discussion of the multisensory instructional system includes remarks concerning the use of films, study…

Coupling of climate models and ice sheet models by surface mass balance gradients: application to the Greenland Ice Sheet

Directory of Open Access Journals (Sweden)

M. M. Helsen

2012-03-01

Full Text Available It is notoriously difficult to couple surface mass balance (SMB results from climate models to the changing geometry of an ice sheet model. This problem is traditionally avoided by using only accumulation from a climate model, and parameterizing the meltwater run-off as a function of temperature, which is often related to surface elevation (H_s. In this study, we propose a new strategy to calculate SMB, to allow a direct adjustment of SMB to a change in ice sheet topography and/or a change in climate forcing. This method is based on elevational gradients in the SMB field as computed by a regional climate model. Separate linear relations are derived for ablation and accumulation, using pairs of H_s and SMB within a minimum search radius. The continuously adjusting SMB forcing is consistent with climate model forcing fields, also for initially non-glaciated areas in the peripheral areas of an ice sheet. When applied to an asynchronous coupled ice sheet – climate model setup, this method circumvents traditional temperature lapse rate assumptions. Here we apply it to the Greenland Ice Sheet (GrIS. Experiments using both steady-state forcing and glacial-interglacial forcing result in realistic ice sheet reconstructions.

SPORT SUPPLEMENTATION

OpenAIRE

Alexandаr Marinkov

2016-01-01

Sport supplementation is essential for athletes performance and achievements. The well balanced and structured supplementation is a challenge for sport medicine because must be done a balance between potential benefits and potential risks (anti-doping rule violations and others). In this review are structured the most used categories sport supplementations. Nutritional supplements used in sport could be divided in some main categories like: amino acids, vitamins, proteins and antioxidants. Fo...

Teacher's Role in Managing the Class During Teaching and Learning Process

OpenAIRE

Rindu, Ignatius; Ariyanti, Ariyanti

2017-01-01

The purpose of this research is to investigate teacher’s roles which used by the English teacher in managing the class during the teaching and learning process at SMP Advent Samarinda. The research methodology used is descriptive design with qualitative approach which is aimed to describe the real situation in the field. In collecting the data, the researcher used questionnaires, observation sheet, field note and interview guide as the instruments. Moreover, the research subject is an English...

Joining of Aluminium Alloy Sheets by Rectangular Mechanical Clinching

International Nuclear Information System (INIS)

Abe, Y.; Mori, K.; Kato, T.

2011-01-01

A mechanical clinching has the advantage of low running costs. However, the joint strength is not high. To improve the maximum load of the joined sheets by a mechanical clinching, square and rectangular mechanical clinching were introduced. In the mechanical clinching, the two sheets are mechanically joined by forming an interlock between the lower and upper sheets by the punch and die. The joined length with the interlock was increased by the rectangular punch and die. The deforming behaviours of the sheets in the mechanical clinching were investigated, and then the interlock in the sheets had distribution in the circumference of the projection. Although the interlocks were formed in both projection side and diagonal, the interlock in the diagonal was smaller because of the long contact length between the lower sheet and the die cavity surface. The maximum load of the joined sheets by the rectangular mechanical clinching was two times larger than the load by the round mechanical clinching.

The properties of bioengineered chondrocyte sheets for cartilage regeneration

Directory of Open Access Journals (Sweden)

Ota Naoshi

2009-03-01

Full Text Available Abstract Background Although the clinical results of autologous chondrocyte implantation for articular cartilage defects have recently improved as a result of advanced techniques based on tissue engineering procedures, problems with cell handling and scaffold imperfections remain to be solved. A new cell-sheet technique has been developed, and is potentially able to overcome these obstacles. Chondrocyte sheets applicable to cartilage regeneration can be prepared with this cell-sheet technique using temperature-responsive culture dishes. However, for clinical application, it is necessary to evaluate the characteristics of the cells in these sheets and to identify their similarities to naive cartilage. Results The expression of SOX 9, collagen type 2, 27, integrin α10, and fibronectin genes in triple-layered chondrocyte sheets was significantly increased in comparison to those in conventional monolayer culture and in a single chondrocyte sheet, implying a nature similar to ordinary cartilage. In addition, immunohistochemistry demonstrated that collagen type II, fibronectin, and integrin α10 were present in the triple-layered chondrocyte sheets. Conclusion The results of this study indicate that these chondrocyte sheets with a consistent cartilaginous phenotype and adhesive properties may lead to a new strategy for cartilage regeneration.

"We Were Told We're Not Teachers... It Gets Difficult to Draw the Line": Negotiating Roles in Peer-Assisted Study Sessions (PASS)

Science.gov (United States)

Brown, Kim; Nairn, Karen; van der Meer, Jacques; Scott, Carole

2014-01-01

Peer learning models in pre-service teacher education are in the early stages of implementation. In this article, we evaluated a pilot Peer-Assisted Study Sessions (PASS) program that supplemented a course for pre-service teachers at one New Zealand university. PASS participants discussed experiences of the program, revealing tensions between what…

Fatigue characteristics of dual-phase steel sheets

Energy Technology Data Exchange (ETDEWEB)

Onn, Irwan Herman; Ahmad, Norhayati; Tamin, Mohd Nasir [Universiti Teknologi Malaysia, Skudai (Malaysia)

2015-01-15

Fatigue characteristics of dual-phase steel sheets, commonly used in automobile body construction were established. For this purpose, a series of fatigue tests, each at constant stress amplitude were conducted on 1.2 mm-thick, dual-phase DP600 steel sheet specimens with two different load ratios of minimum-to-maximum stress, R = 0.1 and -1. The resulting fatigue behavior is expressed in terms of fatigue strength-life (S-N) curves. Fatigue behavior of the steel sheets in the high-cycle fatigue region can be represented by Basquin's equation with coefficient and exponent value of 921.2 and 0.093, respectively. An endurance limit of 255 MPa is observed. In addition, fatigue strengths of the dual-phase steel sheets display lower magnitude than their bulk counterparts. Effect of mean stress on fatigue behavior of the steel sheets is well predicted by Walker's model. Exponential calibration factor is introduced to the models by SWT, Goodman and Morrow with comparable prediction to the Walker's model.

Dynamics of a radially expanding liquid sheet: Experiments

Science.gov (United States)

Majumdar, Nayanika; Tirumkudulu, Mahesh

2017-11-01

A recent theory predicts that sinuous waves generated at the center of a radially expanding liquid sheet grow spatially even in absence of a surrounding gas phase. Unlike flat liquid sheets, the thickness of a radially expanding liquid sheet varies inversely with distance from the center of the sheet. To test the predictions of the theory, experiments were carried out on a horizontal, radially expanding liquid sheet formed by collision of a single jet on a solid impactor. The latter was placed on a speaker-vibrator with controlled amplitude and frequency. The growth of sinuous waves was determined by measuring the wave surface inclination angle using reflected laser light under both atmospheric and sub-atmospheric pressure conditions. It is shown that the measured growth rate matches with the predictions of the theory over a large range of Weber numbers for both pressure conditions suggesting that the thinning of the liquid sheet plays a dominant role in setting the growth rate of sinuous waves with minimal influence of the surrounding gas phase on its dynamics. IIT Bombay.

How to prevent contamination with Candida albicans during the fabrication of transplantable oral mucosal epithelial cell sheets

Directory of Open Access Journals (Sweden)

Ryo Takagi

2015-06-01

Full Text Available We have utilized patients' own oral mucosa as a cell source for the fabrication of transplantable epithelial cell sheets to treat limbal stem cell deficiency and mucosal defects after endoscopic submucosal dissection of esophageal cancer. Because there are abundant microbiotas in the human oral cavity, the oral mucosa was sterilized and 40 μg/mL gentamicin and 0.27 μg/mL amphotericin B were added to the culture medium in our protocol. Although an oral surgeon carefully checked each patient's oral cavity and although candidiasis was not observed before taking the biopsy, contamination with Candida albicans (C. albicans was detected in the conditioned medium during cell sheet fabrication. After adding 1 μg/mL amphotericin B to the transportation medium during transport from Nagasaki University Hospital to Tokyo Women's Medical University, which are 1200 km apart, no proliferation of C. albicans was observed. These results indicated that the supplementation of transportation medium with antimycotics would be useful for preventing contamination with C. albicans derived from the oral mucosa without hampering cell proliferation.

Optimal swimming of a sheet.

Science.gov (United States)

Montenegro-Johnson, Thomas D; Lauga, Eric

2014-06-01

Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

Balance of the West Antarctic Ice Sheet

Science.gov (United States)

2002-01-01

For several decades, measurements of the West Antarctic Ice Sheet showed it to be retreating rapidly. But new data derived from satellite-borne radar sensors show the ice sheet to be growing. Changing Antarctic ice sheets remains an area of high scientific interest, particularly in light of recent global warming concerns. These new findings are significant because scientists estimate that sea level would rise 5-6 meters (16-20 feet) if the ice sheet collapsed into the sea. Do these new measurements signal the end of the ice sheet's 10,000-year retreat? Or, are these new satellite data simply much more accurate than the sparse ice core and surface measurements that produced the previous estimates? Another possibility is that the ice accumulation may simply indicate that the ice sheet naturally expands and retreats in regular cycles. Cryologists will grapple with these questions, and many others, as they examine the new data. The image above depicts the region of West Antarctica where scientists measured ice speed. The fast-moving central ice streams are shown in red. Slower tributaries feeding the ice streams are shown in blue. Green areas depict slow-moving, stable areas. Thick black lines depict the areas that collect snowfall to feed their respective ice streams. Reference: Ian Joughin and Slawek Tulaczyk Science Jan 18 2002: 476-480. Image courtesy RADARSAT Antarctic Mapping Project

Spina Bifida: General Information. Fact Sheet Number 12 = La Espina Bifida: Informacion General. Fact Sheet Number 12.

Science.gov (United States)

National Information Center for Children and Youth with Disabilities, Washington, DC.

This fact sheet offers definitions of the three types of spina bifida, outlines their incidence, describes characteristics of individuals with spina bifida, and reviews educational implications. The fact sheet emphasizes that school programs should be flexible to accommodate these students' special needs and frequent absences, that children with…

Ice Sheets & Ice Cores

DEFF Research Database (Denmark)

Mikkelsen, Troels Bøgeholm

Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known....... The first part concerns time series analysis of ice core data obtained from the Greenland Ice Sheet. We analyze parts of the time series where DO-events occur using the so-called transfer operator and compare the results with time series from a simple model capable of switching by either undergoing...

Microstructure evolution of a dissimilar junction interface between an Al sheet and a Ni-coated Cu sheet joined by magnetic pulse welding

Energy Technology Data Exchange (ETDEWEB)

Itoi, Takaomi, E-mail: itoi@faculty.chiba-u.jp [Department of Mechanical Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Mohamad, Azizan Bin; Suzuki, Ryo [Department of Mechanical Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Okagawa, Keigo [Department of Electrical and Electronics Engineering, Tokyo Metropolitan College of Industrial Technology, 1-10-40 Higashi ohi, Shinagawa-ku, Tokyo 140-0011 (Japan)

2016-08-15

An Al sheet and a Ni-coated Cu sheet were lap joined by using magnetic pulse welding (MPW). Tensile tests were performed on the joined sheets, and a good lap joint was achieved at a discharge energy of > 0.9 kJ. The weld interface exhibited a wavy morphology and an intermediate layer along the weld interface. Microstructure observations of the intermediate layer revealed that the Ni coating region consisted of a Ni–Al binary amorphous alloy and that the Al sheet region contained very fine Al nanograins. Ni fragments indicative of unmelted residual Ni from the coating were also observed in parts of the intermediate layer. Formation of these features can be attributed to localize melting and a subsequent high rate cooling of molten Al and Ni confined to the interface during the MPW process. In the absence of an oxide film, atomic-scale bonding was also achieved between the intermediate layer and the sheet surfaces after the collision. MPW utilises impact energy, which affects the sheet surfaces. From the obtained results, good lap joint is attributed to an increased contact area, the anchor effect, work hardening, the absence of an oxide film, and suppressed formation of intermetallic compounds at the interface. - Highlights: •Good lap joint of an Al sheet and a Ni-coated Cu sheet was achieved by using magnetic pulse welding. •A Ni–Al binary amorphous alloy was formed as an intermediate layer at weld interface. •Atomic-scale bonding was achieved between the intermediate layer and the sheet surfaces.

Synthesis of nanometre-thick MoO3 sheets

Science.gov (United States)

Kalantar-Zadeh, Kourosh; Tang, Jianshi; Wang, Minsheng; Wang, Kang L.; Shailos, Alexandros; Galatsis, Kosmas; Kojima, Robert; Strong, Veronica; Lech, Andrew; Wlodarski, Wojtek; Kaner, Richard B.

2010-03-01

The formation of MoO3 sheets of nanoscale thickness is described. They are made from several fundamental sheets of orthorhombic α-MoO3, which can be processed in large quantities via a low cost synthesis route that combines thermal evaporation and mechanical exfoliation. These fundamental sheets consist of double-layers of linked distorted MoO6 octahedra. Atomic force microscopy (AFM) measurements show that the minimum resolvable thickness of these sheets is 1.4 nm which is equivalent to the thickness of two double-layers within one unit cell of the α-MoO3 crystal.

Fact Sheets on Pesticides in Schools.

Science.gov (United States)

National Coalition against the Misuse of Pesticides, Washington, DC.

This document consists of a collection of fact sheets about the use of pesticides in schools and how to reduce it. The sheets are: (1) "Alternatives to Using Pesticides in Schools: What Is Integrated Pest Management?"; (2) "Health Effects of 48 Commonly Used Pesticides in Schools"; (3) "The Schooling of State Pesticide…

Single clay sheets inside electrospun polymer nanofibers

Science.gov (United States)

Sun, Zhaohui

2005-03-01

Nanofibers were prepared from polymer solution with clay sheets by electrospinning. Plasma etching, as a well controlled process, was used to supply electrically excited gas molecules from a glow discharge. To reveal the structure and arrangement of clay layers in the polymer matrix, plasma etching was used to remove the polymer by controlled gasification to expose the clay sheets due to the difference in reactivity. The shape, flexibility, and orientation of clay sheets were studied by transmission and scanning electron microscopy. Additional quantitative information on size distribution and degree of exfoliation of clay sheets were obtained by analyzing electron micrograph of sample after plasma etching. Samples in various forms including fiber, film and bulk, were thinned by plasma etching. Morphology and dispersion of inorganic fillers were studied by electron microscopy.

Complex world-sheets from N=2 strings

International Nuclear Information System (INIS)

Barbon, J.L.F.

1996-01-01

We study some properties of target space strings constructed from (2,1) heterotic strings. We argue that world-sheet complexification is a general property of the bosonic sector of such target world-sheets. We give a target space interpretation of this fact and relate it to the non-gaussian nature of free string field theory. We provide several one-loop calculations supporting the stringy construction of critical world-sheets in terms of (2,1) models. Using finite-temperature boundary conditions in the underlying (2,1) string we obtain non-chiral target space spin structures, and point out some of the problems arising for chiral spin structures, such as the heterotic world-sheet. To this end, we study the torus partition function of the corresponding asymmetric orbifold of the (2,1) string. (orig.)

Motion and shape of snowplough sheets in coaxial accelerators

International Nuclear Information System (INIS)

Tsagas, N.F.; Mair, G.L.R.; Prinn, A.E.

1978-01-01

A long coaxial accelerator is filled with helium at initial gas pressure between 0.2 and 4 Torr. When connected to a large capacitor at < - 10 kV a discharge is started at one end; the central electrode has negative polarity. The velocity of the plasma sheet, the snowplough, and its shape have been derived from streak photographs for terminal currents between about 100 and 300 kA. The motion of the sheet has been analysed by balancing the electromagnetic driving force against the inertia of the mass of the gas swept up by a plane sheet taken to be impenetrable to gas atoms. The calculated positions and average sheet velocities, which involve simplifying assumptions, have been found to be in good agreement with observations at different positions and pressures. Also the shape of the sheet has been derived by allowing for the sheet's curvature in the linear momentum equation while net radial motions causing variations in profile have, at first, been excluded. The calculated shape of the sheet is very nearly that photographically observed. The axial velocity of a sheet element is evaluated under the assumption that the plasma is azimuthally uniform, free of spikes and that the vessel's wall does not affect the shape. (author)

Corrosion Behavior of Brazed Zinc-Coated Structured Sheet Metal

Directory of Open Access Journals (Sweden)

A. Nikitin

2017-01-01

Full Text Available Arc brazing has, in comparison to arc welding, the advantage of less heat input while joining galvanized sheet metals. The evaporation of zinc is reduced in the areas adjacent to the joint and improved corrosion protection is achieved. In the automotive industry, lightweight design is a key technology against the background of the weight and environment protection. Structured sheet metals have higher stiffness compared to typical automobile sheet metals and therefore they can play an important role in lightweight structures. In the present paper, three arc brazing variants of galvanized structured sheet metals were validated in terms of the corrosion behavior. The standard gas metal arc brazing, the pulsed arc brazing, and the cold metal transfer (CMT® in combination with a pulsed cycle were investigated. In experimental climate change tests, the influence of the brazing processes on the corrosion behavior of galvanized structured sheet metals was investigated. After that, the corrosion behavior of brazed structured and flat sheet metals was compared. Because of the selected lap joint, the valuation of damage between sheet metals was conducted. The pulsed CMT brazing has been derived from the results as the best brazing method for the joining process of galvanized structured sheet metals.

The Workshop Program on Authentic Assessment for Science Teachers

Science.gov (United States)

Rustaman, N. Y.; Rusdiana, D.; Efendi, R.; Liliawati, W.

2017-02-01

A study on implementing authentic assessment program through workshop was conducted to investigate the improvement of the competence of science teachers in designing performance assessment in real life situation at school level context. A number of junior high school science teachers and students as participants were involved in this study. Data was collected through questionnaire, observation sheets, and pre-and post-test during 4 day workshop. This workshop had facilitated them direct experience with seventh grade junior high school students during try out. Science teachers worked in group of four and communicated each other by think-pair share in cooperative learning approach. Research findings show that generally the science teachers’ involvement and their competence in authentic assessment improved. Their knowledge about the nature of assessment in relation to the nature of science and its instruction was improved, but still have problem in integrating their design performance assessment to be implemented in their lesson plan. The 7th grade students enjoyed participating in the science activities, and performed well the scientific processes planned by group of science teachers. The response of science teachers towards the workshop was positive. They could design the task and rubrics for science activities, and revised them after the implementation towards the students. By participating in this workshop they have direct experience in designing and trying out their ability within their professional community in real situation towards their real students in junior high school.

Orientation and Morphology Effects in Rapid Silicon Sheet Solidification

Science.gov (United States)

Ciszek, T. F.

1984-01-01

Radial growth anisotropies and equilibrium forms of point nucleated, dislocation free silicon sheets spreading horizontally on the free surface of a silicon melt were measured for (100), (110), (111), and (112) sheet planes. The growth process was recorded. Qualitative Wulff surface free energy polar plots were deduced from the equilibrium shapes for each sheet plane. Predicted geometries for the tip shape of unidirectional, dislocation free, horizontally grown sheets growing in various directions within the planes were analyzed. Polycrystalline sheets and dendrite propagation were analyzed. For dendrites, growth rates on the order of 2.5 m/min and growth rate anisotropies of 25 are measured.

47 CFR 32.101 - Structure of the balance sheet accounts.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Structure of the balance sheet accounts. 32.101... UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.101 Structure of the balance sheet accounts. The Balance Sheet accounts shall be maintained as follows...

Molding cork sheets to complex shapes

Science.gov (United States)

Sharpe, M. H.; Simpson, W. G.; Walker, H. M.

1977-01-01

Partially cured cork sheet is easily formed to complex shapes and then final-cured. Temperature and pressure levels required for process depend upon resin system used and final density and strength desired. Sheet can be bonded to surface during final cure, or can be first-formed in mold and bonded to surface in separate step.

Whooping Cough (Pertussis) - Fact Sheet for Parents

Science.gov (United States)

... months 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Tosferina (pertussis) The best ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

Characterization of Tensile Mechanical Behavior of MSCs/PLCL Hybrid Layered Sheet

Directory of Open Access Journals (Sweden)

Azizah Intan Pangesty

2016-06-01

Full Text Available A layered construct was developed by combining a porous polymer sheet and a cell sheet as a tissue engineered vascular patch. The primary objective of this study is to investigate the influence of mesenchymal stem cells (MSCs sheet on the tensile mechanical properties of porous poly-(l-lactide-co-ε-caprolactone (PLCL sheet. The porous PLCL sheet was fabricated by the solid-liquid phase separation method and the following freeze-drying method. The MSCs sheet, prepared by the temperature-responsive dish, was then layered on the top of the PLCL sheet and cultured for 2 weeks. During the in vitro study, cellular properties such as cell infiltration, spreading and proliferation were evaluated. Tensile test of the layered construct was performed periodically to characterize the tensile mechanical behavior. The tensile properties were then correlated with the cellular properties to understand the effect of MSCs sheet on the variation of the mechanical behavior during the in vitro study. It was found that MSCs from the cell sheet were able to migrate into the PLCL sheet and actively proliferated into the porous structure then formed a new layer of MSCs on the opposite surface of the PLCL sheet. Mechanical evaluation revealed that the PLCL sheet with MSCs showed enhancement of tensile strength and strain energy density at the first week of culture which is characterized as the effect of MSCs proliferation and its infiltration into the porous structure of the PLCL sheet. New technique was presented to develop tissue engineered patch by combining MSCs sheet and porous PLCL sheet, and it is expected that the layered patch may prolong biomechanical stability when implanted in vivo.

The storm time central plasma sheet

Directory of Open Access Journals (Sweden)

R. Schödel

2002-11-01

Full Text Available The plasma sheet plays a key role during magnetic storms because it is the bottleneck through which large amounts of magnetic flux that have been eroded from the dayside magnetopause have to be returned to the dayside magnetosphere. Using about five years of Geotail data we studied the average properties of the near- and midtail central plasma sheet (CPS in the 10–30 RE range during magnetic storms. The earthward flux transport rate is greatly enhanced during the storm main phase, but shows a significant earthward decrease. Hence, since the magnetic flux cannot be circulated at a sufficient rate, this leads to an average dipolarization of the central plasma sheet. An increase of the specific entropy of the CPS ion population by a factor of about two during the storm main phase provides evidence for nonadiabatic heating processes. The direction of flux transport during the main phase is consistent with the possible formation of a near-Earth neutral line beyond ~20 RE.Key words. Magnetospheric physics (plasma convection; plasma sheet; storms and substorms

Suplemen Panduan Guru dalam Pengembangan Pembelajaran Tematik Kompetensi Dasar Matematika Kelas IV

Directory of Open Access Journals (Sweden)

Isti Hidayah

2013-12-01

Full Text Available AbstrakTujuan penelitian ini adalah untuk mengembangkan perangkat pembelajaran Matematika Sekolah Dasar (SD dengan penguatan tahapan enaktif-ikonik-simbolik berbantuan serang-kaian pertanyaan produktif. Perangkat pembelajaran berupa Panduan Guru sebagai suple-men dalam mengembangkan rancangan pembelajaran tematik kompetensi dasar (KD Ma-tematika kelas IV semester gasal. Penelitian ini telah menghasilkan Panduan Guru dengan perangkatnya, yaitu alat peraga sebagai representasi enaktif; media visual dalam bentuk po-werpoint sebagai representasi ikonik; lembar kegiatan peserta didik (LKPD dan lembar tu-gas peserta didik (LTPD, serta kartu masalah (contextual problem. Produk yang telah di-hasilkan akan membantu guru dalam mengembangkan rancangan pembelajaran dalam im-plementasi Kurikulum 2013. Hasil implementasi menunjukkan bahwa produk penelitian be-rupa Suplemen Panduan Guru membantu guru dalam mengembangkan rancangan dan pe-laksanaan pembelajaran dengan pendekatan ilmiah. Penyempurnaan Suplemen difokuskan pada keterpaduan aspek sikap, keterampilan, dan pengetahuan.Kata kunci: suplemen panduan guru; pembelajaran tematik KD Matematika; contextual                         problem   AbstractThe purpose of this research is to develop elementary mathematics learning devices with reinforcement stages enactive-iconic-symbolic aidednquestion series of productive to strengthen the ability of solving Mathematics problem students since early. A learning device Teacher’s Guide as a supplement in developing basic competencies thematic lesson plan fourth grade Math odd semester. This research has produced a Teacher’s Guide with the device; witch is a representation enactive prop; visual media in the form of PowerPoint as iconic representations; students’ activity sheets (LKPD and students’ task sheet (LTPD, and card problems (contextual problem. The benefit of this research that has been produced to assist teachers in developing

New directions in the science and technology of advanced sheet explosive formulations and the key energetic materials used in the processing of sheet explosives: Emerging trends.

Science.gov (United States)

Talawar, M B; Jangid, S K; Nath, T; Sinha, R K; Asthana, S N

2015-12-30

This review presents the work carried out by the international community in the area of sheet explosive formulations and its applications in various systems. The sheet explosive is also named as PBXs and is a composite material in which solid explosive particles like RDX, HMX or PETN are dispersed in a polymeric matrix, forms a flexible material that can be rolled/cut into sheet form which can be applied to any complex contour. The designed sheet explosive must possess characteristic properties such as flexible, cuttable, water proof, easily initiable, and safe handling. The sheet explosives are being used for protecting tanks (ERA), light combat vehicle and futuristic infantry carrier vehicle from different attacking war heads etc. Besides, sheet explosives find wide applications in demolition of bridges, ships, cutting and metal cladding. This review also covers the aspects such as risks and hazard analysis during the processing of sheet explosive formulations, effect of ageing on sheet explosives, detection and analysis of sheet explosive ingredients and the R&D efforts of Indian researchers in the development of sheet explosive formulations. To the best of our knowledge, there has been no review article published in the literature in the area of sheet explosives. Copyright © 2015 Elsevier B.V. All rights reserved.

Australian Government Balance Sheet Management

OpenAIRE

Wilson Au-Yeung; Jason McDonald; Amanda Sayegh

2006-01-01

Since almost eliminating net debt, the Australian Government%u2019s attention has turned to the financing of broader balance sheet liabilities, such as public sector superannuation. Australia will be developing a significant financial asset portfolio in the %u2018Future Fund%u2019 to smooth the financing of expenses through time. This raises the significant policy question of how best to manage the government balance sheet to reduce risk. This paper provides a framework for optimal balance sh...

Energy information sheets, July 1998

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-07-01

The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

Energy information sheets, September 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-09-01

The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

Anesthesia Fact Sheet

Science.gov (United States)

... Education About NIGMS NIGMS Home > Science Education > Anesthesia Anesthesia Tagline (Optional) Middle/Main Content Area En español ... Version (464 KB) Other Fact Sheets What is anesthesia? Anesthesia is a medical treatment that prevents patients ...

Ice flow Modelling of the Greenland Ice Sheet

DEFF Research Database (Denmark)

Nielsen, Lisbeth Tangaa

Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others. In t...... a steady state with respect to the reference climate at the end of the simulation and that the mass balance of the ice sheet at this time was more sensitive to recent climate fluctuations than the temperature forcing in the early or mid-Holocene.......Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others....... In this PhD project, the use of ice flow models for the interpretation of the age-structure of the Greenland ice sheet, i.e. the depth within the ice, at which ice deposited at given times are found at present day. Two different observational data sets of this archive were investigated. Further, paleo...

Forced tearing of ductile and brittle thin sheets.

Science.gov (United States)

Tallinen, T; Mahadevan, L

2011-12-09

Tearing a thin sheet by forcing a rigid object through it leads to complex crack morphologies; a single oscillatory crack arises when a tool is driven laterally through a brittle sheet, while two diverging cracks and a series of concertinalike folds forms when a tool is forced laterally through a ductile sheet. On the other hand, forcing an object perpendicularly through the sheet leads to radial petallike tears in both ductile and brittle materials. To understand these different regimes we use a combination of experiments, simulations, and simple theories. In particular, we describe the transition from brittle oscillatory tearing via a single crack to ductile concertina tearing with two tears by deriving laws that describe the crack paths and wavelength of the concertina folds and provide a simple phase diagram for the morphologies in terms of the material properties of the sheet and the relative size of the tool.

Self-inhibiting growth of the Greenland Ice Sheet

DEFF Research Database (Denmark)

Langen, Peter Lang; Solgaard, Anne Munck; Hvidberg, Christine Schøtt

2012-01-01

The build-up of the Greenland Ice Sheet (GrIS) from ice-free conditions is studied in an ice sheet model (ISM) driven by fields from an atmospheric general circulation model (GCM) to demonstrate the importance of coupling between the two components. Experiments where the two are coupled off-line...... are augmented by one where an intermediate ice sheet configuration is coupled back to the GCM. Forcing the ISM with GCM fields corresponding to the ice-free state leads to extensive regrowth which, however, is halted when the intermediate recoupling step is included. This inhibition of further growth is due...... to a Föhn effect of moist air parcels being lifted over the intermediate ice sheet and arriving in the low-lying Greenland interior with high temperatures. This demonstrates that two-way coupling between the atmosphere and the ice sheet is essential for understanding the dynamics and that large scale...

Antibubbles and fine cylindrical sheets of air

KAUST Repository

Beilharz, D.

2015-08-14

Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.

Antibubbles and fine cylindrical sheets of air

KAUST Repository

Beilharz, D.; Guyon, A.; Li, E.  Q.; Thoraval, M.-J.; Thoroddsen, Sigurdur T

2015-01-01

Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.

Nonparaxial Bessel and Bessel-Gauss pincers light-sheets

Science.gov (United States)

Mitri, F. G.

2017-01-01

Nonparaxial optical Bessel and Bessel-Gauss pincers optical-sheets are introduced based upon the angular spectrum decomposition in plane waves. The angular spectrum function and the beam-shape coefficients are expressed by means of improper integrals computed numerically. The radiated component of the electric field is also evaluated, displaying unique features of the nonparaxial Bessel pincers light-sheets. This new type of auto-focusing light-sheets finds potential applications in the development of novel methods in optical light-sheet tweezers for particle manipulation in opto-fluidics, particle sizing and imaging. Numerical predictions for the scattering, radiation force and torque, and particle dynamics also benefit from the developed beam solution.

Ice Sheet Roughness Estimation Based on Impulse Responses Acquired in the Global Ice Sheet Mapping Orbiter Mission

Science.gov (United States)

Niamsuwan, N.; Johnson, J. T.; Jezek, K. C.; Gogineni, P.

2008-12-01

The Global Ice Sheet Mapping Orbiter (GISMO) mission was developed to address scientific needs to understand the polar ice subsurface structure. This NASA Instrument Incubator Program project is a collaboration between Ohio State University, the University of Kansas, Vexcel Corporation and NASA. The GISMO design utilizes an interferometric SAR (InSAR) strategy in which ice sheet reflected signals received by a dual-antenna system are used to produce an interference pattern. The resulting interferogram can be used to filter out surface clutter so as to reveal the signals scattered from the base of the ice sheet. These signals are further processed to produce 3D-images representing basal topography of the ice sheet. In the past three years, the GISMO airborne field campaigns that have been conducted provide a set of useful data for studying geophysical properties of the Greenland ice sheet. While topography information can be obtained using interferometric SAR processing techniques, ice sheet roughness statistics can also be derived by a relatively simple procedure that involves analyzing power levels and the shape of the radar impulse response waveforms. An electromagnetic scattering model describing GISMO impulse responses has previously been proposed and validated. This model suggested that rms-heights and correlation lengths of the upper surface profile can be determined from the peak power and the decay rate of the pulse return waveform, respectively. This presentation will demonstrate a procedure for estimating the roughness of ice surfaces by fitting the GISMO impulse response model to retrieved waveforms from selected GISMO flights. Furthermore, an extension of this procedure to estimate the scattering coefficient of the glacier bed will be addressed as well. Planned future applications involving the classification of glacier bed conditions based on the derived scattering coefficients will also be described.

Elementary Science Indoors and Out: Teachers, Time, and Testing

Science.gov (United States)

Carrier, Sarah J.; Tugurian, Linda P.; Thomson, Margareta M.

2013-10-01

In this article, we present the results from a mixed-methods research study aimed to document indoor and outdoor fifth grade science experiences in one school in the USA in the context of accountability and standardized testing. We used quantitative measures to explore students' science knowledge, environmental attitudes, and outdoor comfort levels, and via qualitative measures, we examined views on science education and environmental issues from multiple sources, including the school's principal, teachers, and students. Students' science knowledge in each of the four objectives specified for grade 5 significantly improved during the school year. Qualitative data collected through interviews and observations found limited impressions of outdoor science. Findings revealed that, despite best intentions and a school culture that supported outdoor learning, it was very difficult in practice for teachers to supplement their classroom science instruction with outdoor activities. They felt constrained by time and heavy content demands and decided that the most efficient way of delivering science instruction was through traditional methods. Researchers discuss potentials and obstacles for the science community to consider in supporting teachers and preparing elementary school teachers to provide students with authentic experiential learning opportunities. We further confront teachers' and students' perceptions that science is always best and most efficiently learned inside the classroom through traditional text-driven instruction.

Complementarity in dietary supplements and foods: are supplement users vegetable eaters?

Science.gov (United States)

Kang, Hyoung-Goo; Joo, Hailey Hayeon; Choi, Kyong Duk; Lee, Dongmin; Moon, Junghoon

2017-01-01

Background : The consumption of fruits, vegetables, and dietary supplements correlate. Most previous studies have aimed to identify the determinants of supplement uses or the distinct features of supplement users; this literature lacks a discussion on dietary supplement consumption as a predictor of fruit and vegetable consumption. Objective : This study examines how dietary supplement consumption correlates with fruit and vegetable consumption by combining scanner data and surveys of Korean household grocery shopping. Methods : Propensity score matching (PSM) is used to identify the relationship between dietary supplement consumption and fruit and vegetable consumption in a household. A logit regression using supplement consumption as the dependent variable is used. Then, the supplement takers (the treatment group) are matched with non-takers (the control group) based on the propensity scores estimated in the logit regression. The fruit and vegetable consumption levels of the groups are then compared. Results : We found that dietary supplement use is associated with higher fruit and vegetable consumption. This supports the health consciousness hypothesis based on attention bias, availability heuristics, the focusing effect, and the consumption episode effect. It rejects the health substitute hypothesis based on economic substitutes and mental accounting. Conclusions : Future research on the health benefits of dietary supplements should address the complementary consumption of fruits/vegetables and their health benefits to avoid misstating the health effects of supplements.

Profile of elementary school science teacher instruction in disaster risk reduction: case study of volcano disaster

Science.gov (United States)

Pujianto; Prabowo; Wasis

2018-04-01

This study examined the profile of science' teacher instruction in Disaster Risk Reduction (DRR), as a feature of instructional quality, on students’ learning experiences. A qualitative study was done to observe teacher activities in teaching of disaster preparedness. Science teacher and 14 students at grade 4 of SDN (elementary school) Kiyaran 2 are involved as the subject of this study. Teacher’ instruction was coded with regard to preparation, action, and evaluation using observation sheets and documentation. Data analysis results showed a positive significant effect of the readiness during preparation on learning process of disaster risk reduction and an indirect effect of teacher’ action on students’ learning experiences. There is a lack of teaching materials about volcano disaster in the elementary school. Teacher found difficulties on evaluation of student achievement in disaster preparedness. These findings highlight the importance of DRR in uphold science teachers’ education. Items of teachers’ skill in preparing of DRR may be used to offer model of concrete instruction situation during university workshop for maintain teacher education.

Protein unfolding versus β-sheet separation in spider silk nanocrystals

International Nuclear Information System (INIS)

Alam, Parvez

2014-01-01

In this communication a mechanism for spider silk strain hardening is proposed. Shear failure of β-sheet nanocrystals is the first failure mode that gives rise to the creation of smaller nanocrystals, which are of higher strength and stiffness. β-sheet unfolding requires more energy than nanocrystal separation in a shear mode of failure. As a result, unfolding occurs after the nanocrystals separate in shear. β-sheet unfolding yields a secondary strain hardening effect once the β-sheet conformation is geometrically stable and acts like a unidirectional fibre in a fibre reinforced composite. The mechanism suggested herein is based on molecular dynamics calculations of residual inter-β-sheet separation strengths against residual intra-β-sheet unfolding strengths. (paper)

Cerebral Palsy: General Information. Fact Sheet Number 2 = La Paralisis Cerebral: Informacion General. Fact Sheet Number 18.

Science.gov (United States)

Interstate Research Associates, McLean, VA.

This fact sheet on cerebral palsy is offered in both English and Spanish. First, it provides a definition and considers various causes (e.g., an insufficient amount of oxygen reaching the fetal or newborn brain). The fact sheet then offers incidence figures and explains characteristics of the three main types of cerebral palsy: spastic, athetoid,…

Film sheet cassette

International Nuclear Information System (INIS)

1981-01-01

A novel film sheet cassette is described for handling CAT photographic films under daylight conditions and facilitating their imaging. A detailed description of the design and operation of the cassette is given together with appropriate illustrations. The resulting cassette is a low-cost unit which is easily constructed and yet provides a sure light-tight seal for the interior contents of the cassette. The individual resilient fingers on the light-trap permit the ready removal of the slide plate for taking pictures. The stippled, non-electrostatic surface of the pressure plate ensures an air layer and free slidability of the film for removal and withdrawal of the film sheet. The advantage of the daylight system is that a darkroom need not be used for inserting and removing the film in and out of the cassette resulting in a considerable time saving. (U.K.)

An Adaptive Test Sheet Generation Mechanism Using Genetic Algorithm

Directory of Open Access Journals (Sweden)

Huan-Yu Lin

2012-01-01

Full Text Available For test-sheet composition systems, it is important to adaptively compose test sheets with diverse conceptual scopes, discrimination and difficulty degrees to meet various assessment requirements during real learning situations. Computation time and item exposure rate also influence performance and item bank security. Therefore, this study proposes an Adaptive Test Sheet Generation (ATSG mechanism, where a Candidate Item Selection Strategy adaptively determines candidate test items and conceptual granularities according to desired conceptual scopes, and an Aggregate Objective Function applies Genetic Algorithm (GA to figure out the approximate solution of mixed integer programming problem for the test-sheet composition. Experimental results show that the ATSG mechanism can efficiently, precisely generate test sheets to meet the various assessment requirements than existing ones. Furthermore, according to experimental finding, Fractal Time Series approach can be applied to analyze the self-similarity characteristics of GA’s fitness scores for improving the quality of the test-sheet composition in the near future.

Simulations of the Scandinavian ice sheet and its subsurface conditions

International Nuclear Information System (INIS)

Boulton, G.S.; Caban, P.; Hulton, N.

1999-12-01

An ice sheet model has been applied to an approximate flow line through the area of the Fennoscandian ice sheet. The modelled ice sheet fluctuations have been matched with stratigraphic evidence of Weichselian ice sheet fluctuation in order to simulate ice sheet attributes through time along the flowline. The model predicts extensive melting at the base of the ice sheet. This output has been used as an input to a simplified model of hydrogeology along the southern flank of the ice sheet so as to reconstruct patterns of subglacial groundwater flow. The output from the model is also used to estimate patterns of subglacial stress and strain. Results suggest that large scale subglacial groundwater catchment are formed which were quite different in extent from modern catchment; that fossil subglacial groundwaters should be found at sampling depths; and much fracturing in shallow bedrock in Sweden could be glacially generated

Simulations of the Scandinavian ice sheet and its subsurface conditions

Energy Technology Data Exchange (ETDEWEB)

Boulton, G.S.; Caban, P.; Hulton, N. [Edinburgh Univ. (United Kingdom). Dept of Geology and Geophysics

1999-12-01

An ice sheet model has been applied to an approximate flow line through the area of the Fennoscandian ice sheet. The modelled ice sheet fluctuations have been matched with stratigraphic evidence of Weichselian ice sheet fluctuation in order to simulate ice sheet attributes through time along the flowline. The model predicts extensive melting at the base of the ice sheet. This output has been used as an input to a simplified model of hydrogeology along the southern flank of the ice sheet so as to reconstruct patterns of subglacial groundwater flow. The output from the model is also used to estimate patterns of subglacial stress and strain. Results suggest that large scale subglacial groundwater catchment are formed which were quite differentin extent from modern catchment; that fossil subglacial groundwaters should be found at sampling depths; and much fracturing in shallow bedrock in Sweden could be glacially generated.

Synthesis, characterization and optical properties of sheet-like ZnO

International Nuclear Information System (INIS)

Liu, Changzhen; Meng, Dawei; Wu, Xiuling; Wang, Yongqian; Yu, Xiaohong; Zhang, Zhengjie; Liu, Xiaoyang

2011-01-01

Highlights: → Sheet-like ZnO with regular hexagon shape was synthesized with a two-step method. → Sheet-like ZnO predecessor was synthesized at low temperature in open system. → The diameter and thickness of ZnO sheet can be controlled conveniently. → This low-cost and environmentally benign approach is controllable and reproducible. → Sheet-like ZnO may have potential application in optical and electrical devices. -- Abstract: Sheet-like ZnO with regular hexagon shape and uniform diameter has been successfully synthesized through a two-step method without any metal catalyst. First, the sheet-like ZnO precursor was synthesized in a weak alkaline carbamide environment with stirring in a constant temperature water-bath by the homogeneous precipitation method, then sheet-like ZnO was obtained by calcining at 600 o C for 2 h. The structures and optical properties of sheet-like ZnO have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) and UV-vis-NIR spectrophotometer. The results reveal that the product is highly crystalline with hexagonal wurtzite phase and has appearance of hexagon at (0 0 0 1) plane. The HRTEM images confirm that the individual sheet-like ZnO is single crystal. The PL spectrum exhibits a narrow ultraviolet emission at 397 nm and a broad visible emission centering at 502 nm. The band gap of sheet-like ZnO is about 3.15 eV.

Comparison of Corrosion Behavior of Electrochemically Deposited Nano-Cobalt-Coated Ni Sheet

Directory of Open Access Journals (Sweden)

Nasser Al-Aqeeli

2013-01-01

Full Text Available Corrosion behavior of nano-coblat-coated Ni sheet was compared with pure Ni and 20% Fe-Ni alloy sheet using potentiodynamic polarization and linear polarization technique in 0.1 M NaCl solution at room temperature. Results showed that corrosion resistance properties of nano-Co-coated Ni sheet were almost same as that of pure Ni sheet, however corrosion resistance of 20% Fe-Ni sheet was decreased significantly. Pitting potential of 20% Fe-Ni sheet was subsequently decreased as compared to pure Ni sheet as well as nano-cobalt-coated Ni sheet. SEM/EDS analysis of the corroded surfaces showed that both pure Ni and nano-coblat-coated Ni sheet did not show any appreciable corrosion however significant corrosion was observed in the case of 20% Fe-Ni sheet.

Space Mathematics, A Resource for Teachers Outlining Supplementary Space-Related Problems in Mathematics.

Science.gov (United States)

Reynolds, Thomas D.; And Others

This compilation of 138 problems illustrating applications of high school mathematics to various aspects of space science is intended as a resource from which the teacher may select questions to supplement his regular course. None of the problems require a knowledge of calculus or physics, and solutions are presented along with the problem…

Exploring Potential Uses of ICT in Chinese Language Arts Instruction: Eight Teachers' Perspectives

Science.gov (United States)

Lin, Janet Mei-Chuen; Lee, Greg C.; Chen, Hsiu-Yen

2004-01-01

Eight experienced Chinese language arts teachers from a typical junior high school in Taiwan participated in this study to discuss the potential uses of information and communications technologies (ICT) in Chinese language arts instruction. After meeting for 12 roundtable sessions and using a web forum as a supplement for exchanging ideas, they…

Especially for High School Teachers

Science.gov (United States)

Emory Howell, J.

1999-11-01

More Feature Articles This Month This issue contains a larger-than-usual number of Secondary School Chemistry feature articles (see side-bar). Mary Harris, who teaches in St. Louis, Missouri, and her student, Lauren Picard, contributed an account of student research on the cuprammonium rayon process (p 1512). In addition to being informative and interesting, the article provides a model for student-teacher interaction in carrying out an independent research project. Two North Carolina teachers, Charles Roser and Catherine McCluskey, describe how to use a Calculator Based Laboratory (interface) to measure the kinetics of the reaction that occurs when a lightstick is activated (p 1514). The method and the easy-to-construct device they made could be used with other systems, as well. Don't Throw Away the Carrier Sheet All areas of JCE Online are now accessible to all JCE subscribers. To find out how you can benefit, read the article appearing on p 1599, Now That I Have It, What Can I Do with It? Jon Holmes, Editor of JCE Online, explains in the article how you can use this resource most effectively. Access to several areas, such as full text access to articles, requires that you log in. The mailing label on the carrier sheet that accompanies your Journal each month contains a password that you need to log in. That is why you need to keep the carrier sheet, at least until you have logged in for the first time and either memorized the number or written it in a safe place. Detailed instructions for logging on are found by clicking on the "How to Log On" link, which appears near the upper left corner of the JCE Online Home Page, jchemed.chem.wisc.edu. If you read a school library copy you need to ask your librarian what password you need to log in. Congratulations Among the recipients of the most prestigious American Society Awards (p 1481) are two individuals who have given generously of their time and energy to the cause of chemical education. Both are familiar names to

14 CFR Section 3 - Chart of Balance Sheet Accounts

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Chart of Balance Sheet Accounts Section 3 Section 3 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... Balance Sheet Classifications Section 3 Chart of Balance Sheet Accounts [See footnotes at end of table...

17 CFR 229.1001 - (Item 1001) Summary term sheet.

Science.gov (United States)

2010-04-01

... sheet that is written in plain English. The summary term sheet must briefly describe in bullet point format the most material terms of the proposed transaction. The summary term sheet must provide security... transaction. The bullet points must cross-reference a more detailed discussion contained in the disclosure...

Theoretical Predictions of Freestanding Honeycomb Sheets of Cadmium Chalcogenides

Energy Technology Data Exchange (ETDEWEB)

Zhou, Jia [ORNL; Huang, Jingsong [ORNL; Sumpter, Bobby G [ORNL; Kent, Paul R [ORNL; Xie, Yu [ORNL; Terrones Maldonado, Humberto [ORNL; Smith, Sean C [ORNL

2014-01-01

Two-dimensional (2D) nanocrystals of CdX (X = S, Se, Te) typically grown by colloidal synthesis are coated with organic ligands. Recent experimental work on ZnSe showed that the organic ligands can be removed at elevated temperature, giving a freestanding 2D sheet of ZnSe. In this theoretical work, freestanding single- to few-layer sheets of CdX, each possessing a pseudo honeycomb lattice, are considered by cutting along all possible lattice planes of the bulk zinc blende (ZB) and wurtzite (WZ) phases. Using density functional theory, we have systematically studied their geometric structures, energetics, and electronic properties. A strong surface distortion is found to occur for all of the layered sheets, and yet all of the pseudo honeycomb lattices are preserved, giving unique types of surface corrugations and different electronic properties. The energetics, in combination with phonon mode calculations and molecular dynamics simulations, indicate that the syntheses of these freestanding 2D sheets could be selective, with the single- to few-layer WZ110, WZ100, and ZB110 sheets being favored. Through the GW approximation, it is found that all single-layer sheets have large band gaps falling into the ultraviolet range, while thicker sheets in general have reduced band gaps in the visible and ultraviolet range. On the basis of the present work and the experimental studies on freestanding double-layer sheets of ZnSe, we envision that the freestanding 2D layered sheets of CdX predicted herein are potential synthesis targets, which may offer tunable band gaps depending on their structural features including surface corrugations, stacking motifs, and number of layers.

NTPR Fact Sheets

Science.gov (United States)

History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

The social balance sheet 2004

OpenAIRE

Ph. Delhez; P. Heuse

2005-01-01

Each year, in the 4th quarter’s Economic Review, the National Bank examines the provisional results of the social balance sheets. As all the social balance sheets are not yet available for 2004, the study is based on a limited population of enterprises, compiled according to the principle of a constant sample. This population is made up of 38,530 enterprises employing around 1,331,000 workers in 2004. The main results of the analysis, in terms of employment, working hours, labour cost and tra...

Analysis of Financial Position Based on the Balance Sheet

OpenAIRE

Spineanu-Georgescu Luciana

2011-01-01

Analysis of financial position based on the balance sheet is mainly aimed at assessing the extent to which financial structure chosen by the firm, namely, financial resources, covering the needs reflected in the balance sheet financed. This is done through an analysis known as horizontal analysis balance sheet financial imbalances.

Sense and readability: participant information sheets for research studies.

Science.gov (United States)

Ennis, Liam; Wykes, Til

2016-02-01

Informed consent in research is partly achieved through the use of information sheets. There is a perception however that these information sheets are long and complex. The recommended reading level for patient information is grade 6, or 11-12 years old. To investigate whether the readability of participant information sheets has changed over time, whether particular study characteristics are related to poorer readability and whether readability and other study characteristics are related to successful study recruitment. Method: We obtained 522 information sheets from the UK National Institute for Health Research Clinical Research Network: Mental Health portfolio database and study principal investigators. Readability was assessed with the Flesch reading index and the Grade level test. Information sheets increased in length over the study period. The mean grade level across all information sheets was 9.8, or 15-16 years old. A high level of patient involvement was associated with more recruitment success and studies involving pharmaceutical or device interventions were the least successful. The complexity of information sheets had little bearing on successful recruitment. Information sheets are far more complex than the recommended reading level of grade 6 for patient information. The disparity may be exacerbated by an increasing focus on legal content. Researchers would benefit from clear guidance from ethics committees on writing succinctly and accessibly and how to balance the competing legal issues with the ability of participants to understand what a study entails. © The Royal College of Psychiatrists 2016.

Advanced friction modeling for sheet metal forming

NARCIS (Netherlands)

Hol, J.; Cid Alfaro, M.V.; de Rooij, Matthias B.; Meinders, Vincent T.

2012-01-01

The Coulomb friction model is frequently used for sheet metal forming simulations. This model incorporates a constant coefficient of friction and does not take the influence of important parameters such as contact pressure or deformation of the sheet material into account. This article presents a

Advanced friction modeling in sheet metal forming

NARCIS (Netherlands)

Hol, J.; Cid Alfaro, M.V.; Meinders, Vincent T.; Huetink, Han

2011-01-01

The Coulomb friction model is frequently used for sheet metal forming simulations. This model incorporates a constant coefficient of friction and does not take the influence of important parameters such as contact pressure or deformation of the sheet material into account. This article presents a

Fluoride and sodium trimetaphosphate (TMP release from fluoride varnishes supplemented with TMP

Directory of Open Access Journals (Sweden)

Michele Mauricio MANARELLI

2016-01-01

Full Text Available Abstract This study assessed fluoride (F and sodium trimetaphosphate (TMP release into artificial saliva from varnishes containing 0%, 2.5%, and 5% NaF, supplemented or not with 5% TMP. The varnishes were applied on polyester sheets (n = 8/group, and F and TMP released into artificial saliva were measured for up to 24 hours. The amount of F and TMP released were directly related to NaF and TMP concentrations in the varnishes. The highest F release was seen for 5% NaF and 5% NaF + 5% TMP, whereas 5% TMP released the highest amount of TMP. However, the simultaneous addition of NaF and TMP to varnishes significantly reduced the amount of F and TMP released from the products.

Determinants of dietary supplement use - healthy individuals use dietary supplements

DEFF Research Database (Denmark)

Kofoed, Christina L F; Christensen, Jane; Dragsted, Lars Ove

2015-01-01

influence the use of dietary supplements. Only few studies investigating the use of dietary supplements have been conducted in the Danish population. The present cross-sectional study is based on 54 948 Danes, aged 50-64 years, who completed self-administrated questionnaires on diet, dietary supplements...... and lifestyle between 1993 and 1997. A health index including smoking, physical activity, alcohol and diet, and a metabolic risk index including waist circumference, urinary glucose and measured hypertension were constructed. Logistic regression was used to investigate these determinants in relation...... to the intake of dietary supplements. We found that 71 % of the participants were dietary supplement users; female sex, older age groups and higher educated participants were more likely to be users of any dietary supplements. One additional point in the health index was associated with 19, 16 and 9 % higher...

Nonlinear dynamics of thin current sheets

International Nuclear Information System (INIS)

Daughton, William

2002-01-01

Observations indicate that the current sheet in the Earth's geomagnetic tail may compress to a thickness comparable to an ion gyro-radius prior to substorm onset. In recent years, there has been considerable controversy regarding the kinetic stability of these thin structures. In particular, the growth rate of the kink instability and its relevance to magnetotail dynamics is still being debated. In this work, a series of fully kinetic particle-in-cell simulations are performed for a thin Harris sheet. The ion to electron mass ratio is varied between m i /m e =4→400 and careful comparisons are made with a formally exact approach to the linear Vlasov theory. At low mass ratio m i /m e <64, the simulations are in excellent agreement with the linear theory, but at high mass ratio the kink instability is observed to grow more rapidly in the kinetic simulations than predicted by theory. The resolution to this apparent discrepancy involves the lower hybrid instability which is active on the edge of the sheet and rapidly produces nonlinear modifications to the initial equilibrium. The nature of this nonlinear deformation is characterized and a simple model is proposed to explain the physics. After the growth and saturation of the lower hybrid fluctuations, the deformed current sheet is similar in structure to a Harris equilibrium with an additional background population. This may explain the large growth rate of the kink instability at later times, since this type of modification to the Harris sheet has been shown to greatly enhance the growth rate of the kink mode

Ice Sheet Model Intercomparison Project (ISMIP6) contribution to CMIP6

Science.gov (United States)

Nowicki, Sophie M.J.; Payne, Tony; Larour, Eric; Seroussi, Helene; Goelzer, Heiko; Lipscomb, William; Gregory, Jonathan; Abe-Ouchi, Ayako; Shepherd, Andrew

2018-01-01

Reducing the uncertainty in the past, present and future contribution of ice sheets to sea-level change requires a coordinated effort between the climate and glaciology communities. The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary activity within the Coupled Model Intercomparison Project – phase 6 (CMIP6) focusing on the Greenland and Antarctic Ice Sheets. In this paper, we describe the framework for ISMIP6 and its relationship to other activities within CMIP6. The ISMIP6 experimental design relies on CMIP6 climate models and includes, for the first time within CMIP, coupled ice sheet – climate models as well as standalone ice sheet models. To facilitate analysis of the multi-model ensemble and to generate a set of standard climate inputs for standalone ice sheet models, ISMIP6 defines a protocol for all variables related to ice sheets. ISMIP6 will provide a basis for investigating the feedbacks, impacts, and sea-level changes associated with dynamic ice sheets and for quantifying the uncertainty in ice-sheet-sourced global sea-level change. PMID:29697697

Production (information sheets)

NARCIS (Netherlands)

2007-01-01

Documentation sheets: Geo energy 2 Integrated System Approach Petroleum Production (ISAPP) The value of smartness 4 Reservoir permeability estimation from production data 6 Coupled modeling for reservoir application 8 Toward an integrated near-wellbore model 10 TNO conceptual framework for "E&P

Is Music an Active Developmental Tool or Simply a Supplement? Early Childhood Preservice Teachers' Beliefs about Music

Science.gov (United States)

Kim, Hae Kyoung; Kemple, Kristen M.

2011-01-01

This study examines early childhood preservice teachers' beliefs about the importance of music in early childhood and explores factors influencing those beliefs. The study found that preservice teachers in this study held relatively strong beliefs about the importance of music, including aesthetic, quality-of-life, and social-emotional benefits.…

Evolution of the MHD sheet pinch

International Nuclear Information System (INIS)

Matthaeus, W.H.; Montgomery, D.

1979-01-01

A magnetohydrodynamic (MHD) problem of recurrent interest for both astrophysical and laboratory plasmas is the evolution of the unstable sheet pinch, a current sheet across which a dc magnetic field reverses sign. The evolution of such a sheet pinch is followed with a spectral-method, incompressible, two-dimensional, MHD turbulence code. Spectral diagnostics are employed, as are contour plots of vector potential (magnetic field lines), electric current density, and velocity stream function (velocity streamlines). The nonlinear effect which seems most important is seen to be current filamentation: the concentration of the current density onto sets of small measure near a mgnetic X point. A great deal of turbulence is apparent in the current distribution, which, for high Reynolds numbers, requires large spatial grids (greater than or equal to (64) 2 ). 11 figures, 1 table

Dipole-sheet multipole magnets for accelerators

International Nuclear Information System (INIS)

Walstrom, P.L.

1993-01-01

The dipole-sheet formalism can be used to describe both cylindrical current-sheet multipole magnets and cylindrical-bore magnets made up of permanent magnet blocks. For current sheets, the formalism provides a natural way of finding a finite set of turns that approximate a continuous distribution. The formalism is especially useful In accelerator applications where large-bore, short, high-field-quality magnets that are dominated by fringe fields are needed. A further advantage of the approach is that in systems with either open or cylindrically symmetric magnetic boundaries, analytical expressions for the three-dimensional fields that are suitable for rapid numerical evaluation can be derived. This development is described in some detail. Also, recent developments in higher-order particle-beam optics codes based on the formalism are described briefly

Influence of temperature fluctuations on equilibrium ice sheet volume

Science.gov (United States)

Bøgeholm Mikkelsen, Troels; Grinsted, Aslak; Ditlevsen, Peter

2018-01-01

Forecasting the future sea level relies on accurate modeling of the response of the Greenland and Antarctic ice sheets to changing temperatures. The surface mass balance (SMB) of the Greenland Ice Sheet (GrIS) has a nonlinear response to warming. Cold and warm anomalies of equal size do not cancel out and it is therefore important to consider the effect of interannual fluctuations in temperature. We find that the steady-state volume of an ice sheet is biased toward larger size if interannual temperature fluctuations are not taken into account in numerical modeling of the ice sheet. We illustrate this in a simple ice sheet model and find that the equilibrium ice volume is approximately 1 m SLE (meters sea level equivalent) smaller when the simple model is forced with fluctuating temperatures as opposed to a stable climate. It is therefore important to consider the effect of interannual temperature fluctuations when designing long experiments such as paleo-spin-ups. We show how the magnitude of the potential bias can be quantified statistically. For recent simulations of the Greenland Ice Sheet, we estimate the bias to be 30 Gt yr-1 (24-59 Gt yr-1, 95 % credibility) for a warming of 3 °C above preindustrial values, or 13 % (10-25, 95 % credibility) of the present-day rate of ice loss. Models of the Greenland Ice Sheet show a collapse threshold beyond which the ice sheet becomes unsustainable. The proximity of the threshold will be underestimated if temperature fluctuations are not taken into account. We estimate the bias to be 0.12 °C (0.10-0.18 °C, 95 % credibility) for a recent estimate of the threshold. In light of our findings it is important to gauge the extent to which this increased variability will influence the mass balance of the ice sheets.

Sheet Beam Klystron Instability Analysis

International Nuclear Information System (INIS)

Bane, K.

2009-01-01

Using the principle of energy balance we develop a 2D theory for calculating growth rates of instability in a two-cavity model of a sheet beam klystron. An important ingredient is a TE-like mode in the gap that also gives a longitudinal kick to the beam. When compared with a self-consistent particle-in-cell calculation, with sheet beam klystron-type parameters, agreement is quite good up to half the design current, 65 A; at full current, however, other, current-dependent effects come in and the results deviate significantly

Bi-directional electrons in the near-Earth plasma sheet

Directory of Open Access Journals (Sweden)

K. Shiokawa

2003-07-01

Full Text Available We have studied the occurrence characteristics of bi-directional electron pitch angle anisotropy (enhanced flux in field-aligned directions, F^ /F|| > 1.5 at energies of 0.1–30 keV using plasma and magnetic field data from the AMPTE/IRM satellite in the near-Earth plasma sheet. The occurrence rate increases in the tailward direction from XGSM = - 9 RE to - 19 RE . The occurrence rate is also enhanced in the midnight sector, and furthermore, whenever the elevation angle of the magnetic field is large while the magnetic field intensity is small, B ~ 15 nT. From these facts, we conclude that the bi-directional electrons in the central plasma sheet are produced mainly in the vicinity of the neutral sheet and that the contribution from ionospheric electrons is minor. A high occurrence is also found after earthward high-speed ion flows, suggesting Fermi-type field-aligned electron acceleration in the neutral sheet. Occurrence characteristics of bi-directional electrons in the plasma sheet boundary layer are also discussed.Key words. Magnetospheric physics (magnetospheric configuration and dynamics; magnetotail; plasma sheet

Firm Investment and Balance-Sheet Problems in Japan

OpenAIRE

Toshitaka Sekine

1999-01-01

This paper investigates whether balance-sheet conditions of firms and their main banks matter for firm investment behavior using dynamic corporate panel data in Japan for the period 1985-95. It finds that smaller non-bond issuing firms were facing liquidity constraints; these firms’ balance-sheet conditions (the debt asset ratios) affected their investment from the midst of the bubble era by influencing main banks’ lending to them; and the deterioration of their main banks’ balance-sheet cond...

The quantitative inspection of iron aluminide green sheet using transient thermography

International Nuclear Information System (INIS)

Watkins, Michael L.; Hinders, Mark K.; Scorey, Clive; Winfree, William

1999-01-01

The recent development of manufacturing techniques for the fabrication of thin iron aluminide, FeAl, sheet requires advanced quantitative methods for on-line inspection. An understanding of the mechanisms responsible for flaws and the development of appropriate flaw detection methods are key elements in an effective quality management system. The first step in the fabrication of thin FeAl alloy sheet is the formation of a green sheet, either by cold rolling or tape casting FeAl powder mixed with organic binding agents. The finished sheet is obtained using a series of process steps involving binder elimination, densification, sintering, and annealing. Non-uniformities within the green sheet are the major contributor to material failure in subsequent sheet processing and the production of non-conforming finished sheet. Previous work has demonstrated the advantages of using active thermography to detect the flaws and heterogeneity within green powder composites (1)(2)(3). The production environment and physical characteristics of these composites provide for unique challenges in developing a rapid nondestructive inspection capability. Thermography is non-contact and minimizes the potential damage to the fragile green sheet. Limited access to the material also demands a one-sided inspection technique. In this paper, we will describe the application of thermography for 100% on-line inspection within an industrial process. This approach is cost competitive with alternative technologies, such as x-ray imaging systems, and provides the required sensitivity to the variations in material composition. The formation of green sheet flaws and their transformation into defects within intermediate and finished sheet products will be described. A green sheet conformance criterion will be presented which would significantly reduce the probability of processing poor quality green sheet which contributes to higher waste and inferior bulk alloy sheet

Comparing levels of school performance to science teachers' reports on knowledge/skills, instructional use and student use of computers

Science.gov (United States)

Kerr, Rebecca

The purpose of this descriptive quantitative and basic qualitative study was to examine fifth and eighth grade science teachers' responses, perceptions of the role of technology in the classroom, and how they felt that computer applications, tools, and the Internet influence student understanding. The purposeful sample included survey and interview responses from fifth grade and eighth grade general and physical science teachers. Even though they may not be generalizable to other teachers or classrooms due to a low response rate, findings from this study indicated teachers with fewer years of teaching science had a higher level of computer use but less computer access, especially for students, in the classroom. Furthermore, teachers' choice of professional development moderated the relationship between the level of school performance and teachers' knowledge/skills, with the most positive relationship being with workshops that occurred outside of the school. Eighteen interviews revealed that teachers perceived the role of technology in classroom instruction mainly as teacher-centered and supplemental, rather than student-centered activities.

Antibubbles and fine cylindrical sheets of air

NARCIS (Netherlands)

Beilharz, D.; Guyon, A.; Li, E.Q.; Thoraval, Marie-Jean; Thoroddsen, S.T.

2015-01-01

Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a

The effectiveness of CPI model to improve positive attitude toward science (PATS) for pre-service physics teacher

Science.gov (United States)

Sunarti, T.; Wasis; Madlazim; Suyidno; Prahani, B. K.

2018-03-01

In the previous research, learning material based Construction, Production, and Implementation (CPI) model has been developed to improve scientific literacy and positive attitude toward science for pre-service physics teacher. CPI model has 4 phases, included: 1) Motivation; 2) Construction (Cycle I); 3) Production (Cycle II); and 4) Evaluation. This research is aimed to analyze the effectiveness of CPI model towards the improvement Positive Attitude toward Science (PATS) for pre-service physics teacher. This research used one group pre-test and post-test design on 160 pre-service physics teacher divided into 4 groups at Lambung Mangkurat University and Surabaya State University (Indonesia), academic year 2016/2017. Data collection was conducted through questioner, observation, and interview. Positive attitude toward science for pre-service physics teacher measurement were conducted through Positive Attitude toward Science Evaluation Sheet (PATSES). The data analysis technique was done by using Wilcoxon test and n-gain. The results showed that there was a significant increase in positive attitude toward science for pre-service physics teacher at α = 5%, with n-gain average of high category. Thus, the CPI model is effective for improving positive attitude toward science for pre-service physics teacher.

Reducing Test Anxiety while Increasing Learning: The Cheat Sheet

Science.gov (United States)

Erbe, Brigitte

2007-01-01

Student learning is greatly enhanced by studying prior to an exam. Allowing students to prepare a cheat sheet for the exam helps structure this study time and deepens learning. The crib sheet is well defined: one double-sided page of notes. An award for the best and most creative cheat sheet allows the instructor to appreciate the students'…

Ice sheet hydrology from observations

Energy Technology Data Exchange (ETDEWEB)

Jansson, Peter [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ-, Stockholm (Sweden)

2010-11-15

The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

Ice sheet hydrology from observations

International Nuclear Information System (INIS)

Jansson, Peter

2010-11-01

The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

Laser Indirect Shock Welding of Fine Wire to Metal Sheet.

Science.gov (United States)

Wang, Xiao; Huang, Tao; Luo, Yapeng; Liu, Huixia

2017-09-12

The purpose of this paper is to present an advanced method for welding fine wire to metal sheet, namely laser indirect shock welding (LISW). This process uses silica gel as driver sheet to accelerate the metal sheet toward the wire to obtain metallurgical bonding. A series of experiments were implemented to validate the welding ability of Al sheet/Cu wire and Al sheet/Ag wire. It was found that the use of a driver sheet can maintain high surface quality of the metal sheet. With the increase of laser pulse energy, the bonding area of the sheet/wire increased and the welding interfaces were nearly flat. Energy dispersive spectroscopy (EDS) results show that the intermetallic phases were absent and a short element diffusion layer which would limit the formation of the intermetallic phases emerging at the welding interface. A tensile shear test was used to measure the mechanical strength of the welding joints. The influence of laser pulse energy on the tensile failure modes was investigated, and two failure modes, including interfacial failure and failure through the wire, were observed. The nanoindentation test results indicate that as the distance to the welding interface decreased, the microhardness increased due to the plastic deformation becoming more violent.

Large patternable metal nanoparticle sheets by photo/e-beam lithography

Science.gov (United States)

Saito, Noboru; Wang, Pangpang; Okamoto, Koichi; Ryuzaki, Sou; Tamada, Kaoru

2017-10-01

Techniques for micro/nano-scale patterning of large metal nanoparticle sheets can potentially be used to realize high-performance photoelectronic devices because the sheets provide greatly enhanced electrical fields around the nanoparticles due to localized surface plasmon resonances. However, no single metal nanoparticle sheet currently exists with sufficient durability for conventional lithographical processes. Here, we report large photo and/or e-beam lithographic patternable metal nanoparticle sheets with improved durability by incorporating molecular cross-linked structures between nanoparticles. The cross-linked structures were easily formed by a one-step chemical reaction; immersing a single nanoparticle sheet consisting of core metals, to which capping molecules ionically bond, in a dithiol ethanol solution. The ligand exchange reaction processes were discussed in detail, and we demonstrated 20 μm wide line and space patterns, and a 170 nm wide line of the silver nanoparticle sheets.

Optimal Design of Sheet Pile Wall Embedded in Clay

Science.gov (United States)

Das, Manas Ranjan; Das, Sarat Kumar

2015-09-01

Sheet pile wall is a type of flexible earth retaining structure used in waterfront offshore structures, river protection work and temporary supports in foundations and excavations. Economy is an essential part of a good engineering design and needs to be considered explicitly in obtaining an optimum section. By considering appropriate embedment depth and sheet pile section it may be possible to achieve better economy. This paper describes optimum design of both cantilever and anchored sheet pile wall penetrating clay using a simple optimization tool Microsoft Excel ® Solver. The detail methodology and its application with examples are presented for cantilever and anchored sheet piles. The effects of soil properties, depth of penetration and variation of ground water table on the optimum design are also discussed. Such a study will help professional while designing the sheet pile wall penetrating clay.

How might the North American ice sheet influence the northwestern Eurasian climate?

Science.gov (United States)

Beghin, P.; Charbit, S.; Dumas, C.; Kageyama, M.; Ritz, C.

2015-10-01

It is now widely acknowledged that past Northern Hemisphere ice sheets covering Canada and northern Europe at the Last Glacial Maximum (LGM) exerted a strong influence on climate by causing changes in atmospheric and oceanic circulations. In turn, these changes may have impacted the development of the ice sheets themselves through a combination of different feedback mechanisms. The present study is designed to investigate the potential impact of the North American ice sheet on the surface mass balance (SMB) of the Eurasian ice sheet driven by simulated changes in the past glacial atmospheric circulation. Using the LMDZ5 atmospheric circulation model, we carried out 12 experiments under constant LGM conditions for insolation, greenhouse gases and ocean. In these experiments, the Eurasian ice sheet is removed. The 12 experiments differ in the North American ice-sheet topography, ranging from a white and flat (present-day topography) ice sheet to a full-size LGM ice sheet. This experimental design allows the albedo and the topographic impacts of the North American ice sheet onto the climate to be disentangled. The results are compared to our baseline experiment where both the North American and the Eurasian ice sheets have been removed. In summer, the sole albedo effect of the American ice sheet modifies the pattern of planetary waves with respect to the no-ice-sheet case, resulting in a cooling of the northwestern Eurasian region. By contrast, the atmospheric circulation changes induced by the topography of the North American ice sheet lead to a strong decrease of this cooling. In winter, the Scandinavian and the Barents-Kara regions respond differently to the American ice-sheet albedo effect: in response to atmospheric circulation changes, Scandinavia becomes warmer and total precipitation is more abundant, whereas the Barents-Kara area becomes cooler with a decrease of convective processes, causing a decrease of total precipitation. The gradual increase of the

The Realities of Teaching Elementary Mathematics by Student Teachers: A Phenomenological Probe

Directory of Open Access Journals (Sweden)

Jo Ann M. Petancio

2018-02-01

Full Text Available This study probed into the lived experiences of the student-teachers as they go through teaching Elementary Mathematics. Apart from Mathematics, these student-teachers who are generalists teach the other seven subjects. This phenomenological study was conducted during the first semester, school year 2017-2018 in Cebu Normal University-Integrated Laboratory School in Cebu City, Philippines. The researchers interviewed twelve student teachers and used Colaizzi’s method of data analysis. Results revealed that the essence of teaching Math from the lens of elementary student teachers is condensed in the following themes: a Emotional mix-up; b Challenging; c Never stop learning and reach out for help; d Success is a joint venture of teacher and student; e Values count; f We are work in progress. The researchers recommend that teacher education institutions may consider revisiting their policies and practices to strengthen the support lent by the supervisor, mentors and staff to the budding teachers; providing supplemental training and coaching towards improving the student teachers’ pedagogical content knowledge in Math; and providing the pre-service teachers with reflective strategies in processing one’s own experiences in teaching the subject. Moreover, since elementary student-teachers teach not only Math but the other subjects as well, the researchers also recommend that further researches may be conducted on topics related on how the teaching of the other subjects influence one’s way of teaching Mathematics.

Breakup characteristics of power-law liquid sheets formed by two impinging jets

International Nuclear Information System (INIS)

Bai, Fuqiang; Diao, Hai; Chang, Qing; Wang, Endong; Du, Qing; Zhang, Mengzheng

2014-01-01

The breakup characteristics of the shear-thinning power-law liquid sheets formed by two impinging jets have been investigated with the shadowgraph technique. This paper focuses on the effects of spray parameters (jet velocity), physical parameters (viscosity) and geometry parameters (impinging angle and nozzle cross-sectional shape) on the breakup behaviors of liquid sheets. The breakup mode, sheet length and expansion angle of the sheet are extracted from the spray images obtained by a high speed camera. Impinging angle and Weber number play the similar roles in promoting the breakup of liquid sheets. With the increase of jet velocity, five different breakup modes are observed and the expansion angle increases consistently after the closed-rim mode while the sheet length first increases and then decreases. But there exists a concave consisting of a fierce drop and a second rising process on the sheet length curve for the fluid with smaller viscosity. Different nozzle cross-sectional shapes emphasize significant effects on the sheet length and expansion angle of liquid sheets. At a fixed Weber number, the liquid sheet with greater viscosity has a greater sheet length and a smaller expansion angle due to the damping effect of viscosity. (papers)

Fatigue analysis of a PWR steam generator tube sheet

International Nuclear Information System (INIS)

Billon, F.; Buchalet, C.; Poudroux, G.

1985-01-01

The fatigue analysis of a PWR steam generator (S.G) tube sheet is threefold. First, the flow, pressure and temperature variations during the design transients are defined for both the primary fluid and the normal and auxiliary feedwater. Second, the flow, velocities, pressure and temperature variations of the secondary fluid at the bottom of the downcomer and above the tube sheet are determined for the transients considered. Finally, the corresponding temperatures and stresses in the tube sheet are calculated and the usage factors determined at various locations in the tube sheet. The currently available standard design transients for the primary fluid and the feedwater are too conservative to be utilized as such in the fatigue analysis of the S.G. tube sheets. Thus, a detailed examination and reappraisal of each operating transient was performed. The revised design conditions are used as inputs to the calculation model TEMPTRON. TEMPTRON determines the mixing conditions between the feedwater and the recirculation fluid from the S.G. feedwater nozzles to the center of the tube sheet via the downcomer. The fluid parameters, flow rate and velocity, temperature and pressure variations, as a function of the time during the transients are obtained. Finally, the usage factors at various locations on the tube sheet are derived using the standard ASME section III method

Grounding line transient response in marine ice sheet models

Directory of Open Access Journals (Sweden)

A. S. Drouet

2013-03-01

Full Text Available Marine ice-sheet stability is mostly controlled by the dynamics of the grounding line, i.e. the junction between the grounded ice sheet and the floating ice shelf. Grounding line migration has been investigated within the framework of MISMIP (Marine Ice Sheet Model Intercomparison Project, which mainly aimed at investigating steady state solutions. Here we focus on transient behaviour, executing short-term simulations (200 yr of a steady ice sheet perturbed by the release of the buttressing restraint exerted by the ice shelf on the grounded ice upstream. The transient grounding line behaviour of four different flowline ice-sheet models has been compared. The models differ in the physics implemented (full Stokes and shallow shelf approximation, the numerical approach, as well as the grounding line treatment. Their overall response to the loss of buttressing is found to be broadly consistent in terms of grounding line position, rate of surface elevation change and surface velocity. However, still small differences appear for these latter variables, and they can lead to large discrepancies (> 100% observed in terms of ice sheet contribution to sea level when cumulated over time. Despite the recent important improvements of marine ice-sheet models in their ability to compute steady state configurations, our results question the capacity of these models to compute short-term reliable sea-level rise projections.

A laser sheet self-calibration method for scanning PIV

Science.gov (United States)

Knutsen, Anna N.; Lawson, John M.; Dawson, James R.; Worth, Nicholas A.

2017-10-01

Knowledge of laser sheet position, orientation, and thickness is a fundamental requirement of scanning PIV and other laser-scanning methods. This paper describes the development and evaluation of a new laser sheet self-calibration method for stereoscopic scanning PIV, which allows the measurement of these properties from particle images themselves. The approach is to fit a laser sheet model by treating particles as randomly distributed probes of the laser sheet profile, whose position is obtained via a triangulation procedure enhanced by matching particle images according to their variation in brightness over a scan. Numerical simulations and tests with experimental data were used to quantify the sensitivity of the method to typical experimental error sources and validate its performance in practice. The numerical simulations demonstrate the accurate recovery of the laser sheet parameters over range of different seeding densities and sheet thicknesses. Furthermore, they show that the method is robust to significant image noise and camera misalignment. Tests with experimental data confirm that the laser sheet model can be accurately reconstructed with no impairment to PIV measurement accuracy. The new method is more efficient and robust in comparison with the standard (self-) calibration approach, which requires an involved, separate calibration step that is sensitive to experimental misalignments. The method significantly improves the practicality of making accurate scanning PIV measurements and broadens its potential applicability to scanning systems with significant vibrations.

Middle Schoolers and Magazines: What Teachers Can Learn from Students' Leisure Reading Habits

Science.gov (United States)

Gabriel, Rachael; Allington, Richard; Billen, Monica

2012-01-01

Teachers, parents, and librarians are constantly looking for methods and materials that engage students as readers and motivate them to increase the time they spend reading. In this article we describe findings from a study of middle schoolers' magazine reading habits that gave us a close look at the power of magazines as supplemental supports for…

Teacher Perceptions of Their Curricular and Pedagogical Shifts: Outcomes of a Project-Based Model of Teacher Professional Development in the Next Generation Science Standards.

Science.gov (United States)

Shernoff, David J; Sinha, Suparna; Bressler, Denise M; Schultz, Dawna

2017-01-01

In this study, we conducted a model of teacher professional development (PD) on the alignment of middle and high school curricula and instruction to the Next Generation Science Standards (NGSSs), and evaluated the impact of the PD on teacher participants' development. The PD model included a 4-day summer academy emphasizing project-based learning (PBL) in the designing of NGSS-aligned curricula and instruction, as well as monthly follow-up Professional Learning Community meetings throughout the year providing numerous opportunities for teachers to develop and implement lesson plans, share results of lesson writing and implementation (successes and challenges), provide mutual feedback, and refine curricula and assessments. Following the summer academy, six female teachers were interviewed about their current conceptualizations of NGSS, the extent of curricular shifts made that are required by NGSS, their self-perceptions regarding their level of accomplishment in curriculum writing, and the benefits of the PD in reaching their goals related to NGSS. Interviews were supplemented with an analysis of lesson plans written while participating in the PD program. The interviewed teachers suggested that they had made important conceptual and pedagogical shifts required by NGSS as they participated in the PD, and also noted a variety of challenges as they made this shift. While all teachers were relative novices at NGSS curriculum writing before the PD, most of the teachers interviewed felt that they had achieved the status of an "accomplished novice" following the summer academy. An analysis of their written lessons suggested a great range in the extent to which teachers effectively applied their understanding of NGSS to write lessons aligned to NGSS. Interviewed teachers believed that the PD model was helpful to their development as science teachers, and all reported that there were no aspects of the PD that were not helpful. Even though most teachers obtained a basic

TEACHERS WHO TEACH MATHEMATICS IN ADULT EDUCATION: CONCEPTS AND TEACHING PRACTICES

Directory of Open Access Journals (Sweden)

Andréa Thees

2012-12-01

Full Text Available This work represents a subset of a Masters’ research, which investigated how the pedagogical and non-pedagogical professional practices of mathematics teachers who teach in adult education are developed. In this paper we present the curricular management practices, tasks and materials, communication and evaluation. Through a case study of the daily activities of three math teachers who teach young people and adults, a qualitative research was developed, whose investigative tools were field observations, semi-structured interviews and questionnaires. Our study indicated that curriculum management practices are determined by a straightforward exposition teaching style, based on problem solving. Regarding the proposed tasks, teachers do not resort to learning materials other than blackboard and chalk, and rarely use the textbook. Communication in the classroom is univocal, sometimes supplemented by inadequate metaphors, especially in the teaching of algebra. The practices of student evaluation are predominantly focused on the summative function.

16 CFR 460.15 - How installers must handle fact sheets.

Science.gov (United States)

2010-01-01

... ADVERTISING OF HOME INSULATION § 460.15 How installers must handle fact sheets. If you are an installer, you... from you, you must show them the fact sheet(s) for the type(s) of insulation they want. You can decide...

Ice sheets on plastically-yielding beds

Science.gov (United States)

Hewitt, Ian

2016-11-01

Many fast flowing regions of ice sheets are underlain by a layer of water-saturated sediments, or till. The rheology of the till has been the subject of some controversy, with laboratory tests suggesting almost perfectly plastic behaviour (stress independent of strain rate), but many models adopting a pseudo-viscous description. In this work, we consider the behaviour of glaciers underlain by a plastic bed. The ice is treated as a viscous gravity current, on a bed that allows unconstrained slip above a critical yield stress. This simplified description allows rapid sliding, and aims to investigate 'worst-case' scenarios of possible ice-sheet disintegration. The plastic bed results in an approximate ice-sheet geometry that is primarily controlled by force balance, whilst ice velocity is determined from mass conservation (rather than the other way around, as standard models would hold). The stability of various states is considered, and particular attention is given to the pace at which transitions between unstable states can occur. Finally, we observe that the strength of basal tills depends strongly on pore pressure, and combine the model with a description of subglacial hydrology. Implications for the present-day ice sheets in Greenland and Antarctica will be discussed. Funding: ERC Marie Curie FP7 Career Integration Grant.

Pseudomonas - Fact Sheet

OpenAIRE

Public Health Agency

2012-01-01

Fact sheet on Pseudomonas, including:What is Pseudomonas?What infections does it cause?Who is susceptible to pseudomonas infection?How will I know if I have pseudomonas infection?How can Pseudomonas be prevented from spreading?How can I protect myself from Pseudomonas?How is Pseudomonas infection treated?

Continuous development of current sheets near and away from magnetic nulls

International Nuclear Information System (INIS)

Kumar, Sanjay; Bhattacharyya, R.

2016-01-01

The presented computations compare the strength of current sheets which develop near and away from the magnetic nulls. To ensure the spontaneous generation of current sheets, the computations are performed congruently with Parker's magnetostatic theorem. The simulations evince current sheets near two dimensional and three dimensional magnetic nulls as well as away from them. An important finding of this work is in the demonstration of comparative scaling of peak current density with numerical resolution, for these different types of current sheets. The results document current sheets near two dimensional magnetic nulls to have larger strength while exhibiting a stronger scaling than the current sheets close to three dimensional magnetic nulls or away from any magnetic null. The comparative scaling points to a scenario where the magnetic topology near a developing current sheet is important for energetics of the subsequent reconnection.

How is the Inquiry Skills of Biology Preservice Teachers in Biotechnology Lecture?

Science.gov (United States)

Hayat, M. S.; Rustaman, N. Y.

2017-09-01

This study was to investigate the inquiry skills of biology pre-service teachers in one teachers college in Central Java in biotechnology lecture. The method used is a case study of 29 biology preservice teacher. Data were collected using observation sheets, questionnaires, and interview guidelines. Research findings collected through questionnaires show that most students are accustomed to asking questions and formulating biotechnology issues; Skilled in conducting experiments; Skilled in obtaining relevant information from various sources; As well as skilled at processing, analyzing and interpreting data. Based on observation: lectures are not dominated by lecturers, students are able to solve problems encountered and conduct investigations. Based on the interview towards lecturers: students are always actively involved in questioning, investigation, inquiry, problem solving and experimenting in lectures. Why do most students show good inquiry skills? Because students are accustomed to invited inquiry in biology lectures. The impact, the students become more ready to be invited to do more advanced inquiry, such as real-world application inquiry, because the skill of inquiry is essentially trained.

Dynamic Antarctic ice sheet during the early to mid-Miocene

Science.gov (United States)

Gasson, Edward; DeConto, Robert M.; Pollard, David; Levy, Richard H.

2016-03-01

Geological data indicate that there were major variations in Antarctic ice sheet volume and extent during the early to mid-Miocene. Simulating such large-scale changes is problematic because of a strong hysteresis effect, which results in stability once the ice sheets have reached continental size. A relatively narrow range of atmospheric CO2 concentrations indicated by proxy records exacerbates this problem. Here, we are able to simulate large-scale variability of the early to mid-Miocene Antarctic ice sheet because of three developments in our modeling approach. (i) We use a climate-ice sheet coupling method utilizing a high-resolution atmospheric component to account for ice sheet-climate feedbacks. (ii) The ice sheet model includes recently proposed mechanisms for retreat into deep subglacial basins caused by ice-cliff failure and ice-shelf hydrofracture. (iii) We account for changes in the oxygen isotopic composition of the ice sheet by using isotope-enabled climate and ice sheet models. We compare our modeling results with ice-proximal records emerging from a sedimentological drill core from the Ross Sea (Andrill-2A) that is presented in a companion article. The variability in Antarctic ice volume that we simulate is equivalent to a seawater oxygen isotope signal of 0.52-0.66‰, or a sea level equivalent change of 30-36 m, for a range of atmospheric CO2 between 280 and 500 ppm and a changing astronomical configuration. This result represents a substantial advance in resolving the long-standing model data conflict of Miocene Antarctic ice sheet and sea level variability.

Ice Sheet Model Intercomparison Project (ISMIP6) Contribution to CMIP6

Science.gov (United States)

Nowicki, Sophie M. J.; Payne, Tony; Larour, Eric; Seroussi, Helene; Goelzer, Heiko; Lipscomb, William; Gregory, Jonathan; Abe-Ouchi, Ayako; Shepherd, Andrew

2016-01-01

Reducing the uncertainty in the past, present, and future contribution of ice sheets to sea-level change requires a coordinated effort between the climate and glaciology communities. The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary activity within the Coupled Model Intercomparison Project phase 6 (CMIP6) focusing on the Greenland and Antarctic ice sheets. In this paper, we describe the framework for ISMIP6 and its relationship with other activities within CMIP6. The ISMIP6 experimental design relies on CMIP6 climate models and includes, for the first time within CMIP, coupled ice-sheetclimate models as well as standalone ice-sheet models. To facilitate analysis of the multi-model ensemble and to generate a set of standard climate inputs for standalone ice-sheet models, ISMIP6 defines a protocol for all variables related to ice sheets. ISMIP6 will provide a basis for investigating the feedbacks, impacts, and sea-level changes associated with dynamic ice sheets and for quantifying the uncertainty in ice-sheet-sourced global sea-level change.

Microstructural Changes in Brazing Sheet due to Solid-Liquid Interaction

NARCIS (Netherlands)

Wittebrood, A.J.

2009-01-01

Aluminium brazing sheet is the material of choice to produce automotive heat exchangers. Although in Dutch the official translation of aluminium brazing sheet is “aluminium hardsoldeerplaat” the English name is used in the industry. Aluminium brazing sheet is basically a sandwich material and

Transfer of fibroblast sheets cultured on thermoresponsive dishes with membranes.

Science.gov (United States)

Kawecki, Marek; Kraut, Małgorzata; Klama-Baryła, Agnieszka; Łabuś, Wojciech; Kitala, Diana; Nowak, Mariusz; Glik, Justyna; Sieroń, Aleksander L; Utrata-Wesołek, Alicja; Trzebicka, Barbara; Dworak, Andrzej; Szweda, Dawid

2016-06-01

In cell or tissue engineering, it is essential to develop a support for cell-to-cell adhesion, which leads to the generation of cell sheets connected by extracellular matrix. Such supports must be hydrophobic and should result in a detachable cell sheet. A thermoresponsive support that enables the cultured cell sheet to detach using only a change in temperature could be an interesting alternative in regenerative medicine. The aim of this study was to evaluate plates covered with thermoresponsive polymers as supports for the formation of fibroblast sheets and to develop a damage-free procedure for cell sheet transfer with the use of membranes as transfer tools. Human skin fibroblasts were seeded on supports coated with a thermoresponsive polymer: commercial UpCell™ dishes (NUNC™) coated with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and dishes coated with thermoresponsive poly(tri(ethylene glycol) monoethyl ether methacrylate) (P(TEGMA-EE)). Confluent fibroblast sheets were effectively cultured and harvested from both commercial PNIPAM-coated dishes and laboratory P(TEGMA-EE)-coated dishes. To transfer a detached cell sheet, two membranes, Immobilon-P(®) and SUPRATHEL(®), were examined. The use of SUPRATHEL for relocating the cell sheets opens a new possibility for the clinical treatment of wounds. This study established the background for implementing thermoresponsive supports for transplanting in vitro cultured fibroblasts.

Endogenous Sheet-Averaged Tension Within a Large Epithelial Cell Colony.

Science.gov (United States)

Dumbali, Sandeep P; Mei, Lanju; Qian, Shizhi; Maruthamuthu, Venkat

2017-10-01

Epithelial cells form quasi-two-dimensional sheets that function as contractile media to effect tissue shape changes during development and homeostasis. Endogenously generated intrasheet tension is a driver of such changes, but has predominantly been measured in the presence of directional migration. The nature of epithelial cell-generated forces transmitted over supracellular distances, in the absence of directional migration, is thus largely unclear. In this report, we consider large epithelial cell colonies which are archetypical multicell collectives with extensive cell-cell contacts but with a symmetric (circular) boundary. Using the traction force imbalance method (TFIM) (traction force microscopy combined with physical force balance), we first show that one can determine the colony-level endogenous sheet forces exerted at the midline by one half of the colony on the other half with no prior assumptions on the uniformity of the mechanical properties of the cell sheet. Importantly, we find that this colony-level sheet force exhibits large variations with orientation-the difference between the maximum and minimum sheet force is comparable to the average sheet force itself. Furthermore, the sheet force at the colony midline is largely tensile but the shear component exhibits significantly more variation with orientation. We thus show that even an unperturbed epithelial colony with a symmetric boundary shows significant directional variation in the endogenous sheet tension and shear forces that subsist at the colony level.

Influence of temperature fluctuations on equilibrium ice sheet volume

Directory of Open Access Journals (Sweden)

T. B. Mikkelsen

2018-01-01

Full Text Available Forecasting the future sea level relies on accurate modeling of the response of the Greenland and Antarctic ice sheets to changing temperatures. The surface mass balance (SMB of the Greenland Ice Sheet (GrIS has a nonlinear response to warming. Cold and warm anomalies of equal size do not cancel out and it is therefore important to consider the effect of interannual fluctuations in temperature. We find that the steady-state volume of an ice sheet is biased toward larger size if interannual temperature fluctuations are not taken into account in numerical modeling of the ice sheet. We illustrate this in a simple ice sheet model and find that the equilibrium ice volume is approximately 1 m SLE (meters sea level equivalent smaller when the simple model is forced with fluctuating temperatures as opposed to a stable climate. It is therefore important to consider the effect of interannual temperature fluctuations when designing long experiments such as paleo-spin-ups. We show how the magnitude of the potential bias can be quantified statistically. For recent simulations of the Greenland Ice Sheet, we estimate the bias to be 30 Gt yr−1 (24–59 Gt yr−1, 95 % credibility for a warming of 3 °C above preindustrial values, or 13 % (10–25, 95 % credibility of the present-day rate of ice loss. Models of the Greenland Ice Sheet show a collapse threshold beyond which the ice sheet becomes unsustainable. The proximity of the threshold will be underestimated if temperature fluctuations are not taken into account. We estimate the bias to be 0.12 °C (0.10–0.18 °C, 95 % credibility for a recent estimate of the threshold. In light of our findings it is important to gauge the extent to which this increased variability will influence the mass balance of the ice sheets.

Continuous liquid sheet generator for ion stripping

International Nuclear Information System (INIS)

Gavin, B.; Batson, P.; Leemann, B.; Rude, B.

1984-10-01

Many of the technical problems of generating a large thin liquid sheet from 0.02 to 0.20 μm thick (3 to 40 μgm/cm 2 ) have been solved. It is shown that this perennial sheet is stable and consonant in dimension. Several ion beam species from the SuperHILAC have been used for evaluation; at 0.11 MeV/n. In one of three modes this sheet serves as an equivalent substitute for a carbon foil. The second mode is characterized by a solid-like charge state distribution but with a varying fraction of unstripped ions. The third mode gives stripping performance akin to a vapor stripping medium. 9 references, 7 figures

Simulation spread sheet of Angra-1 secondary circuit

International Nuclear Information System (INIS)

Futuro, F.L.; Rucos, J.; Ogando, A.; Maprelian, E.; Bassel, W.S.; Baptista Filho, B.D.

2000-01-01

The efficient operation of a Nuclear Power Plant (NPP) requires the continuous identification of derivations in the main operating parameters. The identification and analysis of those derivations allow someone to detect the degradation of instruments or even of any equipment. In order to study this problem the group of thermal generation of Angra 1 NPP, devised the use of a Microsoft Excel spread sheet for the automation of Angra 1 thermal balance. In the set of simulation spread sheets, measured values of the secondary system main parameters were compared with project values for a given reactor power level and condenser pressure. The spread sheets provide the turbines power and efficiency and do the plant thermal balance. This work presents a general description of the spread sheets set and a real case analysis of Angra 1 NPP, showing its precision and use easiness. (author)

The Potsdam Parallel Ice Sheet Model (PISM-PIK) - Part 2: Dynamic equilibrium simulation of the Antarctic ice sheet

Science.gov (United States)

Martin, M. A.; Winkelmann, R.; Haseloff, M.; Albrecht, T.; Bueler, E.; Khroulev, C.; Levermann, A.

2011-09-01

We present a dynamic equilibrium simulation of the ice sheet-shelf system on Antarctica with the Potsdam Parallel Ice Sheet Model (PISM-PIK). The simulation is initialized with present-day conditions for bed topography and ice thickness and then run to steady state with constant present-day surface mass balance. Surface temperature and sub-shelf basal melt distribution are parameterized. Grounding lines and calving fronts are free to evolve, and their modeled equilibrium state is compared to observational data. A physically-motivated calving law based on horizontal spreading rates allows for realistic calving fronts for various types of shelves. Steady-state dynamics including surface velocity and ice flux are analyzed for whole Antarctica and the Ronne-Filchner and Ross ice shelf areas in particular. The results show that the different flow regimes in sheet and shelves, and the transition zone between them, are captured reasonably well, supporting the approach of superposition of SIA and SSA for the representation of fast motion of grounded ice. This approach also leads to a natural emergence of sliding-dominated flow in stream-like features in this new 3-D marine ice sheet model.

75 FR 55340 - Recovery Fact Sheet 9580.100, Mold Remediation

Science.gov (United States)

2010-09-10

...] Recovery Fact Sheet 9580.100, Mold Remediation AGENCY: Federal Emergency Management Agency, DHS. ACTION... accepting comments on Recovery Fact Sheet RP9580.100, Mold Remediation. DATES: Comments must be received by... 20472-3100. II. Background The Recovery Fact Sheet RP9580.100, Mold Remediation, identifies the expenses...

Balance velocities of the Greenland ice sheet

DEFF Research Database (Denmark)

Joughin, I.; Fahnestock, M.; Ekholm, Simon

1997-01-01

We present a map of balance velocities for the Greenland ice sheet. The resolution of the underlying DEM, which was derived primarily from radar altimetery data, yields far greater detail than earlier balance velocity estimates for Greenland. The velocity contours reveal in striking detail......, the balance map is useful for ice-sheet modelling, mass balance studies, and field planning....

Cholera Fact Sheet

Science.gov (United States)

... news-room/fact-sheets/detail/cholera","@context":"http://schema.org","@type":"Article"}; العربية 中文 français русский español ... that includes feedback at the local level and information-sharing at the global level. Cholera cases are ...

Magneto-hydrodynamics of coupled fluid–sheet interface with mass suction and blowing

International Nuclear Information System (INIS)

Ahmad, R.

2016-01-01

There are large number of studies which prescribe the kinematics of the sheet and ignore the sheet's mechanics. However, the current boundary layer analysis investigates the mechanics of both the electrically conducting fluid and a permeable sheet, which makes it distinct from the other studies in the literature. One of the objectives of the current study is to (i) examine the behaviour of magnetic field effect for both the surface and the electrically conducting fluid (ii) investigate the heat and mass transfer between a permeable sheet and the surrounding electrically conducting fluid across the hydro, thermal and mass boundary layers. Self-similar solutions are obtained by considering the RK45 technique. Analytical solution is also found for the stretching sheet case. The skin friction dual solutions are presented for various types of sheet. The influence of pertinent parameters on the dimensionless velocity, shear stress, temperature, mass concentration, heat and mass transfer rates on the fluid–sheet interface is presented graphically as well as numerically. The obtained results are of potential benefit for studying the electrically conducting flow over various soft surfaces such as synthetic plastics, soft silicone sheet and soft synthetic rubber sheet. These surfaces are easily deformed by thermal fluctuations or thermal stresses. - Highlights: • The momentum equation is modelled for both the surrounding MHD fluid and the sheet with the effects of mass suction and blowing. • The current study further investigates the heat and mass transfer characteristics between a permeable sheet and the surrounding electrically conducting fluid across the thermal and mass boundary layers. • Both the approximated and analytical techniques have been included for the purpose of comparison, and the perfect numerical agreements have been established with the previous studies. • Dual solutions for the skin friction coefficients are found for various categories of

Composite cell sheet for periodontal regeneration: crosstalk between different types of MSCs in cell sheet facilitates complex periodontal-like tissue regeneration.

Science.gov (United States)

Zhang, Hao; Liu, Shiyu; Zhu, Bin; Xu, Qiu; Ding, Yin; Jin, Yan

2016-11-14

Tissue-engineering strategies based on mesenchymal stem cells (MSCs) and cell sheets have been widely used for periodontal tissue regeneration. However, given the complexity in periodontal structure, the regeneration methods using a single species of MSC could not fulfill the requirement for periodontal regeneration. We researched the interaction between the periodontal ligament stem cells (PDLSCs) and jaw bone marrow-derived mesenchymal stem cells (JBMMSCs), and constructed a composite cell sheet comprising both of the above MSCs to regenerate complex periodontium-like structures in nude mice. Our results show that by co-culturing PDLSCs and JBMMSCs, the expressions of bone and extracellular matrix (ECM)-related genes and proteins were significantly improved in both MSCs. Further investigations showed that, compared to the cell sheet using PDLSCs or JBMMSCs, the composite stem cell sheet (CSCS), which comprises these two MSCs, expressed higher levels of bone- and ECM-related genes and proteins, and generated a composite structure more similar to the native periodontal tissue physiologically in vivo. In conclusion, our results demonstrate that the crosstalk between PDLSCs and JBMMSCs in cell sheets facilitate regeneration of complex periodontium-like structures, providing a promising new strategy for physiological and functional regeneration of periodontal tissue.

Effects of electron pressure anisotropy on current sheet configuration

Energy Technology Data Exchange (ETDEWEB)

Artemyev, A. V., E-mail: aartemyev@igpp.ucla.edu; Angelopoulos, V.; Runov, A. [Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90095 (United States); Vasko, I. Y. [Space Research Institute, RAS, Moscow (Russian Federation)

2016-09-15

Recent spacecraft observations in the Earth's magnetosphere have demonstrated that the magnetotail current sheet can be supported by currents of anisotropic electron population. Strong electron currents are responsible for the formation of very thin (intense) current sheets playing the crucial role in stability of the Earth's magnetotail. We explore the properties of such thin current sheets with hot isotropic ions and cold anisotropic electrons. Decoupling of the motions of ions and electrons results in the generation of a polarization electric field. The distribution of the corresponding scalar potential is derived from the electron pressure balance and the quasi-neutrality condition. We find that electron pressure anisotropy is partially balanced by a field-aligned component of this polarization electric field. We propose a 2D model that describes a thin current sheet supported by currents of anisotropic electrons embedded in an ion-dominated current sheet. Current density profiles in our model agree well with THEMIS observations in the Earth's magnetotail.

Effects of electron pressure anisotropy on current sheet configuration

International Nuclear Information System (INIS)

Artemyev, A. V.; Angelopoulos, V.; Runov, A.; Vasko, I. Y.

2016-01-01

Recent spacecraft observations in the Earth's magnetosphere have demonstrated that the magnetotail current sheet can be supported by currents of anisotropic electron population. Strong electron currents are responsible for the formation of very thin (intense) current sheets playing the crucial role in stability of the Earth's magnetotail. We explore the properties of such thin current sheets with hot isotropic ions and cold anisotropic electrons. Decoupling of the motions of ions and electrons results in the generation of a polarization electric field. The distribution of the corresponding scalar potential is derived from the electron pressure balance and the quasi-neutrality condition. We find that electron pressure anisotropy is partially balanced by a field-aligned component of this polarization electric field. We propose a 2D model that describes a thin current sheet supported by currents of anisotropic electrons embedded in an ion-dominated current sheet. Current density profiles in our model agree well with THEMIS observations in the Earth's magnetotail.

Structural Biology Fact Sheet

Science.gov (United States)

... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

Friction and lubrication modelling in sheet metal forming: Influence of lubrication amount, tool roughness and sheet coating on product quality

Science.gov (United States)

Hol, J.; Wiebenga, J. H.; Carleer, B.

2017-09-01

In the stamping of automotive parts, friction and lubrication play a key role in achieving high quality products. In the development process of new automotive parts, it is therefore crucial to accurately account for these effects in sheet metal forming simulations. This paper presents a selection of results considering friction and lubrication modelling in sheet metal forming simulations of a front fender product. For varying lubrication conditions, the front fender can either show wrinkling or fractures. The front fender is modelled using different lubrication amounts, tool roughness’s and sheet coatings to show the strong influence of friction on both part quality and the overall production stability. For this purpose, the TriboForm software is used in combination with the AutoForm software. The results demonstrate that the TriboForm software enables the simulation of friction behaviour for varying lubrication conditions, i.e. resulting in a generally applicable approach for friction characterization under industrial sheet metal forming process conditions.

The electrostatics of charged insulating sheets peeled from grounded conductors

International Nuclear Information System (INIS)

Datta, M J; Horenstein, M N

2008-01-01

The physics of a charged, insulating sheet peeled from a ground-plane conductor is examined. Contact charging is ensured by charging a sheet to 10-12 kV with corona to establish intimate electrostatic contact with the underlying conductor. The surface potential is next forced to zero by sweeping the sheet with a stainless-steel brush, and the surface recharged to a new potential between 0 and 11 kV. The sheet is then peeled from the ground plane and its residual charge density is measured. Results show that the residual charge equals the breakdown-limiting value, but its polarity depends on the surface potential acquired just prior to peeling. The results have relevance to studies of industrial webs and insulating sheets.

Calcium supplements

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/007477.htm Calcium supplements To use the sharing features on this page, please enable JavaScript. WHO SHOULD TAKE CALCIUM SUPPLEMENTS? Calcium is an important mineral for the ...

Behavior of protruding lateral plane graphene sheets in liquid dodecane: molecular dynamics simulations

Energy Technology Data Exchange (ETDEWEB)

Chen, Shenghui; Sun, Shuangqing, E-mail: sunshuangqing@upc.edu.cn; Li, Chunling [China University of Petroleum (East China), College of Science (China); Pittman, Charles U. [Mississippi State University, Department of Chemistry (United States); Lacy, Thomas E. [Mississippi State University, Department of Aerospace Engineering (United States); Hu, Songqing, E-mail: songqinghu@upc.edu.cn [China University of Petroleum (East China), College of Science (China); Gwaltney, Steven R. [Mississippi State University, Department of Chemistry (United States)

2016-11-15

Molecular dynamics simulations are used to investigate the behavior of two parallel graphene sheets fixed on one edge (lateral plane) in liquid dodecane. The interactions of these sheets and dodecane molecules are studied with different starting inter-sheet distances. The structure of the dodecane solvent is also analyzed. The results show that when the distance between the two graphene sheets is short (less than 6.8 Å), the sheets will expel the dodecane molecules between them and stack together. However, when the distance between two sheets is large (greater than 10.2 Å), the two sheets do not come together, and the dodecane molecules will form ordered layers in the interlayer spacing. The equilibrium distance between the graphene sheets can only take on specific discrete values (3.4, 7.8, and 12.1 Å), because only an integer number of dodecane layers forms between the two sheets. Once the graphene sheets are in contact, they remain in contact; the sheets do not separate to allow dodecane into the interlayer spacing.

Continental Ice Sheets and the Planetary Radiation Budget

NARCIS (Netherlands)

Oerlemans, J.

1980-01-01

The interaction between continental ice sheets and the planetary radiation budget is potentially important in climate-sensitivity studies. A simple ice-sheet model incorporated in an energybalance climate model provides a tool for studying this interaction in a quantitative way. Experiments in which

Best Management Practice Fact Sheet. 12, Filtering Practices

OpenAIRE

Sample, David; Barlow, Stefani

2013-01-01

This fact sheet is one of a 15-part series on urban stormwater management practices. This fact sheet discusses filtering practices, what they are, where they are used, how they work, maintenance, limitations, performance, expected costs and includes a glossary of terms.

Best Management Practice Fact Sheet. 10, Dry Swale

OpenAIRE

Sample, David; Doumar, Lia

2013-01-01

This fact sheet is one of a 15-part series on urban stormwater management practices. This fact sheet discusses dry swales, what they are, where they are used, how they work, maintenance, limitations, performance, expected costs and includes a glossary of terms.

Best Management Practice Fact Sheet. 11, Wet Swale

OpenAIRE

Sample, David; Doumar, Lia

2013-01-01

This fact sheet is one of a 15-part series on urban stormwater management practices. This fact sheet discusses wet swales, what they are, where they are used, how they work, maintenance, limitations, performance, expected costs and includes a glossary of terms.

Vortices on the string and superstring world sheets

International Nuclear Information System (INIS)

Abrikosov, A.A.; Kogan, Ya.I.

1989-01-01

The world-sheet dynamics of the first quantized string propagating in non-simply connected space is considered. Presence of the vortices on the world sheet lead to Berezinsky-Kosterlitz-Thouless(BKT) phase transition. Bosonic and superstring cases are discussed. 20 refs.; 2 figs

Characterization of Platinum Nanoparticles Deposited on Functionalized Graphene Sheets

Directory of Open Access Journals (Sweden)

Yu-Chun Chiang

2015-09-01

Full Text Available Due to its special electronic and ballistic transport properties, graphene has attracted much interest from researchers. In this study, platinum (Pt nanoparticles were deposited on oxidized graphene sheets (cG. The graphene sheets were applied to overcome the corrosion problems of carbon black at operating conditions of proton exchange membrane fuel cells. To enhance the interfacial interactions between the graphene sheets and the Pt nanoparticles, the oxygen-containing functional groups were introduced onto the surface of graphene sheets. The results showed the Pt nanoparticles were uniformly dispersed on the surface of graphene sheets with a mean Pt particle size of 2.08 nm. The Pt nanoparticles deposited on graphene sheets exhibited better crystallinity and higher oxygen resistance. The metal Pt was the predominant Pt chemical state on Pt/cG (60.4%. The results from the cyclic voltammetry analysis showed the value of the electrochemical surface area (ECSA was 88 m2/g (Pt/cG, much higher than that of Pt/C (46 m2/g. The long-term test illustrated the degradation in ECSA exhibited the order of Pt/C (33% > Pt/cG (7%. The values of the utilization efficiency were calculated to be 64% for Pt/cG and 32% for Pt/C.

Resveratrol food supplements

DEFF Research Database (Denmark)

Aschemann-Witzel, Jessica; Grunert, Klaus G

2015-01-01

Background: Consumers increasingly choose food supplements in addition to their diet. Research on supplement users finds they are likely to be female, older and well-educated; Furthermore, supplement users are often characterised as being especially health-oriented, an observation which is termed...... the ‘inverse supplement hypothesis’. However, results are dependent on the substance in question. Little is known so far about botanicals in general, and more specifically, little is known about resveratrol. The psychographic variables of food supplement users are yet relatively underexplored. By comparing US...... and Danish respondents, we aimed to identify whether sociodemographic variables, health status, health beliefs and behaviour and interest in food aspects specifically relevant to resveratrol (e.g., naturalness, indulgence, and Mediterranean food) explain favourable attitudes and adoption intentions toward...

The Response of Ice Sheets to Climate Variability

Science.gov (United States)

Snow, K.; Goldberg, D. N.; Holland, P. R.; Jordan, J. R.; Arthern, R. J.; Jenkins, A.

2017-12-01

West Antarctic Ice Sheet loss is a significant contributor to sea level rise. While the ice loss is thought to be triggered by fluctuations in oceanic heat at the ice shelf bases, ice sheet response to ocean variability remains poorly understood. Using a synchronously coupled ice-ocean model permitting grounding line migration, this study evaluates the response of an ice sheet to periodic variations in ocean forcing. Resulting oscillations in grounded ice volume amplitude is shown to grow as a nonlinear function of ocean forcing period. This implies that slower oscillations in climatic forcing are disproportionately important to ice sheets. The ice shelf residence time offers a critical time scale, above which the ice response amplitude is a linear function of ocean forcing period and below which it is quadratic. These results highlight the sensitivity of West Antarctic ice streams to perturbations in heat fluxes occurring at decadal time scales.

Hibernia fact sheet

International Nuclear Information System (INIS)

Anon.

1994-01-01

This fact sheet gives details of the Hibernia oil field including its location, discovery date, oil company's interests in the project, the recoverable reserves of the two reservoirs, the production system used, capital costs of the project, and overall targets for Canadian benefit. Significant dates for the Hibernia project are listed. (UK)

A simple holistic hypothesis for the self-destruction of ice sheets

Science.gov (United States)

Hughes, T.

2011-07-01

Ice sheets are the only components of Earth's climate system that can self-destruct. This paper presents the quantitative force balance for bottom-up modeling of ice sheets, as first presented qualitatively in this journal as a way to quantify ice-bed uncoupling leading to self-destruction of ice sheets ( Hughes, 2009a). Rapid changes in sea level and climate can result if a large ice-sheet self-destructs quickly, as did the former Laurentide Ice Sheet of North America between 8100 and 7900 BP, thereby terminating the last cycle of Quaternary glaciation. Ice streams discharge up to 90 percent of ice from past and present ice sheets. A hypothesis is presented in which self-destruction of an ice sheet begins when ubiquitous ice-bed decoupling, quantified as a floating fraction of ice, proceeds along ice streams. This causes ice streams to surge and reduce thickness by some 90 percent, and height above sea level by up to 99 percent for floating ice, so the ice sheet undergoes gravitational collapse. Ice collapsing over marine embayments becomes floating ice shelves that may then disintegrate rapidly. This floods the world ocean with icebergs that reduce the ocean-to-atmosphere heat exchange, thereby triggering climate change. Calving bays migrate up low stagnating ice streams and carve out the accumulation zone of the collapsed ice sheet, which prevents its recovery, decreases Earth's albedo, and terminates the glaciation cycle. This sequence of events may coincide with a proposed life cycle of ice streams that drain the ice sheet. A first-order treatment of these life cycles is presented that depends on the longitudinal force balance along the flowbands of ice streams and gives a first approximation to ice-bed uncoupling at snapshots during gravitational collapse into ice shelves that disintegrate, thereby removing the ice sheet. The stability of the Antarctic Ice Sheet is assessed using this bottom-up approach.

Teaching Astronomy through e-learning in Poland: Astronomical Education in teacher training conducted by the Regional Teacher Training Center in Skierniewice

Science.gov (United States)

Dabrowska, A. E.

2014-12-01

Regional Teacher Training Centre (RTTC) in Skierniewice is one of 49 public, accredited institutions in Poland carrying out it statutory goals at the regional level. It has been operating since 1989 and is responsible for organizing of support of schools, institutions, networks of teachers for cooperation and self-education, organizing various forms of in-service training and disseminating examples of good practice. It also has rich experience in teaching by using modern Interactive Computer Technology (ICT) tools and e-learning platform. I present examples about teaching of Astronomical issues through teacher training both as hands on workshops as well as through e-learning. E-learning is playing an important role in organizing educational activities not only in the field of modern didactic but also in learning Science subjects. Teachers find e-learning as a very economical, easy and convenient way of learning and developing their knowledge and skills. Moreover, they are no longer afraid of using new ICT tools and programs which help them to cooperate with students effectively. Since 2011 RTTC in Skierniewice has been an organizer of many on-line in-service programs for teachers, in learning Science. Some of them are organized as blended-learning programs which allow teachers to participate first in hands on activities then continue learning on the Moodle platform. These courses include two 15 and 30-hours of Astronomical topics. Teachers have the opportunity to gain knowledge and receive materials not only about the Universe and the Solar System but also can learn to use tools like Stellarium, Celestia, WorldWide Telescope, Your Sky and other tools. E-learning modules consist of both publishing learning materials in various forms, eg. PowerPoint Presentations, Word & PDF materials, web sites, publications, working sheets as well as practical duties like participation in chats, forums, tasks, Wiki, group workshop. Teachers use these materials for extending their

Balance sheet capacity and endogenous risk

OpenAIRE

Jon Danielsson; Hyun Song Shin; Jean-Pierre Zigrand

2011-01-01

Banks operating under Value-at-Risk constraints give rise to a well-defined aggregate balance sheet capacity for the banking sector as a whole that depends on total bank capital. Equilibrium risk and market risk premiums can be solved in closed form as functions of aggregate bank capital. We explore the empirical properties of the model in light of recent experience in the financial crisis and highlight the importance of balance sheet capacity as the driver of the financial cycle and market r...

Symmetry breaking bifurcations of a current sheet

International Nuclear Information System (INIS)

Parker, R.D.; Dewar, R.L.; Johnson, J.L.

1990-01-01

Using a time evolution code with periodic boundary conditions, the viscoresistive hydromagnetic equations describing an initially static, planar current sheet with large Lundquist number have been evolved for times long enough to reach a steady state. A cosh 2 x resistivity model was used. For long periodicity lengths L p , the resistivity gradient drives flows that cause forced reconnection at X point current sheets. Using L p as a bifurcation parameter, two new symmetry breaking bifurcations were found: a transition to an asymmetric island chain with nonzero, positive, or negative phase velocity, and a transition to a static state with alternating large and small islands. These states are reached after a complex transient behavior, which involves a competition between secondary current sheet instability and coalescence

Tuning the mechanical properties of vertical graphene sheets through atomic layer deposition

International Nuclear Information System (INIS)

Davami, Keivan; Jiang, Yijie; Cortes, John; Lin, Chen; Turner, Kevin T; Bargatin, Igor; Shaygan, Mehrdad

2016-01-01

We report the fabrication and characterization of graphene nanostructures with mechanical properties that are tuned by conformal deposition of alumina. Vertical graphene (VG) sheets, also called carbon nanowalls (CNWs), were grown on copper foil substrates using a radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) technique and conformally coated with different thicknesses of alumina (Al_2O_3) using atomic layer deposition (ALD). Nanoindentation was used to characterize the mechanical properties of pristine and alumina-coated VG sheets. Results show a significant increase in the effective Young’s modulus of the VG sheets with increasing thickness of deposited alumina. Deposition of only a 5 nm thick alumina layer on the VG sheets nearly triples the effective Young’s modulus of the VG structures. Both energy absorption and strain recovery were lower in VG sheets coated with alumina than in pure VG sheets (for the same peak force). This may be attributed to the increase in bending stiffness of the VG sheets and the creation of connections between the sheets after ALD deposition. These results demonstrate that the mechanical properties of VG sheets can be tuned over a wide range through conformal atomic layer deposition, facilitating the use of VG sheets in applications where specific mechanical properties are needed. (paper)

Principles for designing proteins with cavities formed by curved β sheets

Energy Technology Data Exchange (ETDEWEB)

Marcos, Enrique; Basanta, Benjamin; Chidyausiku, Tamuka M.; Tang, Yuefeng; Oberdorfer, Gustav; Liu, Gaohua; Swapna, G. V. T.; Guan, Rongjin; Silva, Daniel-Adriano; Dou, Jiayi; Pereira, Jose Henrique; Xiao, Rong; Sankaran, Banumathi; Zwart, Peter H.; Montelione, Gaetano T.; Baker, David

2017-01-12

Active sites and ligand-binding cavities in native proteins are often formed by curved β sheets, and the ability to control β-sheet curvature would allow design of binding proteins with cavities customized to specific ligands. Toward this end, we investigated the mechanisms controlling β-sheet curvature by studying the geometry of β sheets in naturally occurring protein structures and folding simulations. The principles emerging from this analysis were used to design, de novo, a series of proteins with curved β sheets topped with α helices. Nuclear magnetic resonance and crystal structures of the designs closely match the computational models, showing that β-sheet curvature can be controlled with atomic-level accuracy. Our approach enables the design of proteins with cavities and provides a route to custom design ligand-binding and catalytic sites.

Modelling the Antarctic Ice Sheet

DEFF Research Database (Denmark)

Pedersen, Jens Olaf Pepke; Holm, A.

2015-01-01

to sea level high stands during past interglacial periods. A number of AIS models have been developed and applied to try to understand the workings of the AIS and to form a robust basis for future projections of the AIS contribution to sea level change. The recent DCESS (Danish Center for Earth System......The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...

Silicon Sheet Quality is Improved By Meniscus Control

Science.gov (United States)

Yates, D. A.; Hatch, A. E.; Goldsmith, J. M.

1983-01-01

Better quality silicon crystals for solar cells are possible with instrument that monitors position of meniscus as sheet of solid silicon is drawn from melt. Using information on meniscus height, instrument generates feedback signal to control melt temperature. Automatic control ensures more uniform silicon sheets.

Oscillations of spherical fullerenes interacting with graphene sheet

Energy Technology Data Exchange (ETDEWEB)

Ghavanloo, Esmaeal, E-mail: ghavanloo@shirazu.ac.ir; Fazelzadeh, S. Ahmad

2017-01-01

In the present study, the oscillations of spherical fullerenes in the vicinity of a fully constrained graphene sheet are investigated. Using the continuous approximation and Lennard-Jones potential, the van der Waals (vdW) potential energy and interaction forces are obtained. The equation of motion is derived and directly solved based on the actual force distribution between the fullerene molecules and the graphene sheet. Numerical results are obtained and shown that the oscillation is sensitive to the size of the fullerene as well as the distance between the center of the fullerene and the graphene sheet.

Magma transport in sheet intrusions of the Alnö carbonatite complex, central Sweden.

Science.gov (United States)

Andersson, Magnus; Almqvist, Bjarne S G; Burchardt, Steffi; Troll, Valentin R; Malehmir, Alireza; Snowball, Ian; Kübler, Lutz

2016-06-10

Magma transport through the Earth's crust occurs dominantly via sheet intrusions, such as dykes and cone-sheets, and is fundamental to crustal evolution, volcanic eruptions and geochemical element cycling. However, reliable methods to reconstruct flow direction in solidified sheet intrusions have proved elusive. Anisotropy of magnetic susceptibility (AMS) in magmatic sheets is often interpreted as primary magma flow, but magnetic fabrics can be modified by post-emplacement processes, making interpretation of AMS data ambiguous. Here we present AMS data from cone-sheets in the Alnö carbonatite complex, central Sweden. We discuss six scenarios of syn- and post-emplacement processes that can modify AMS fabrics and offer a conceptual framework for systematic interpretation of magma movements in sheet intrusions. The AMS fabrics in the Alnö cone-sheets are dominantly oblate with magnetic foliations parallel to sheet orientations. These fabrics may result from primary lateral flow or from sheet closure at the terminal stage of magma transport. As the cone-sheets are discontinuous along their strike direction, sheet closure is the most probable process to explain the observed AMS fabrics. We argue that these fabrics may be common to cone-sheets and an integrated geology, petrology and AMS approach can be used to distinguish them from primary flow fabrics.

Should Cheat Sheets be Used as Study Aids in Economics Tests?

OpenAIRE

Yoav Wachsman

2002-01-01

This paper reports an experiment that investigates the effectiveness of cheat sheets as study aids for economics tests. A cheat sheet is a piece of paper that students can write anything they want on and use during a test. I find that both preparing and using a cheat sheet improves students' test performance. Additionally, there is no evidence that students become over dependent on their cheat sheets for answers.

Bamboo Fibre Reinforced Cement Used as a Roofing Sheet | Alade ...

African Journals Online (AJOL)

Bamboo fibre roofing sheet was able to withstand an average load of 51Kg, which is above the minimum required strength of 50kg. Comparatively, Asbestos roofing sheets and coconut fibre roofing sheets of similar dimensions had failure loads of 104.65Kg and 79Kg respectively. When immersed in water, bamboo fibre ...

Solar wind and substorm excitation of the wavy current sheet

Directory of Open Access Journals (Sweden)

C. Forsyth

2009-06-01

Full Text Available Following a solar wind pressure pulse on 3 August 2001, GOES 8, GOES 10, Cluster and Polar observed dipolarizations of the magnetic field, accompanied by an eastward expansion of the aurora observed by IMAGE, indicating the occurrence of two substorms. Prior to the first substorm, the motion of the plasma sheet with respect to Cluster was in the ZGSM direction. Observations following the substorms show the occurrence of current sheet waves moving predominantly in the −YGSM direction. Following the second substorm, the current sheet waves caused multiple current sheet crossings of the Cluster spacecraft, previously studied by Zhang et al. (2002. We further this study to show that the velocity of the current sheet waves was similar to the expansion velocity of the substorm aurora and the expansion of the dipolarization regions in the magnetotail. Furthermore, we compare these results with the current sheet wave models of Golovchanskaya and Maltsev (2005 and Erkaev et al. (2008. We find that the Erkaev et al. (2008 model gives the best fit to the observations.

Tearing resistance of some co-polyester sheets

International Nuclear Information System (INIS)

Kim, Ho Sung; Karger-Kocsis, Jozsef

2004-01-01

A three-zone model consisting of initial, evolutionary and stabilised plastic zones for tearing resistance was proposed for polymer sheets. An analysis with the model, based on the essential work of fracture (EWF) approach, was demonstrated to be capable for predicting specific total work of fracture along the tear path across all the plastic zones although accuracy of specific essential work of fracture is subject to improvement. Photo-elastic images were used for identification of plastic deformation sizes and profiles. Fracture mode change during loading was described in relation with the three zones. Tearing fracture behaviour of extruded mono- and bi-layer sheets of different types of amorphous co-polyesters and different thicknesses was investigated. Thick material exhibited higher specific total work of tear fracture than thin mono-layer sheet in the case of amorphous polyethylene terephthalate (PET). This finding was explained in terms of plastic zone size formed along the tear path, i.e., thick material underwent larger plastic deformation than thin material. When PET and polyethylene terephthalate glycol (PETG) were laminated with each other, specific total work of fracture of the bi-layer sheets was not noticeably improved over that of the constituent materials

Evaluation of congruence among dietary supplement use and motivation for supplementation in young, Canadian athletes.

Science.gov (United States)

Parnell, Jill A; Wiens, Kristin; Erdman, Kelly Anne

2015-01-01

Dietary supplement use is endemic in young athletes; however, it is unclear if their choices are congruent with their motivation for supplementation and the established benefits of the dietary supplements. The aim of this study was to evaluate the relationships between dietary supplement use and self-reported rationale in young athletes. Canadian athletes (n = 567; 11-25 years; 76% club or provincial level, 24% national or higher) completed a questionnaire designed to assess supplementation patterns and motivation for supplementation. Chi square tests examined associations between dietary supplements and self-reported rationale for use. Vitamin and mineral supplements, including vitamin-enriched water, were associated with several health- and performance- related reasons (p performance reasons, as were performance foods (protein powder, sport bars, sport gels, etc.). Plant extracts and fatty acids were primarily associated with health reasons, particularly immune support (p performance rationales and supplementation for common ergogenic aids, however, less so for vitamin and mineral supplements, vitamin-enriched water, and plant extracts. Incongruences were found between fatty acids, protein supplements, vitamin and mineral supplements, vitamin-enriched water, and plant extracts and health motivators for supplementation. Educational interventions are essential to ensure young athletes are using dietary supplements safely and effectively.

Annual Energy Balance Sheets 2001-2002

International Nuclear Information System (INIS)

2004-01-01

During the year 2002 the primary supply of energy reached 629 TWh, which is 7.7 TWh less than 2001. The decrease originates mainly from the reduced electricity production from water power. Also the electricity production in nuclear power plants decreased by 4.5 TWh. If we were to look at the supplied energy for final consumption we will find a slightly rise by 1.8 TWh. The year 2002 was warmer than a 'normal' year and that consequently brings lower energy needs. Compared with 2001, 2002 was not warmer and a net electricity import of 5.4 TWh covered the energy needs. The energy use increased by 3.3 TWh between 2002 and 2001. The industry sector shows the largest rise by 2.9 TWh, nearly 2 per cent. Within that sector, energy from biomass fuel had a rise by 6.7 per cent. The household sector decreases its energy use by 2.7 per cent, and oil and electricity show the largest decrease. The proportionately high electricity price probably had a slowing down effect on the electricity use. The balance sheets of energy sources are showing the total supply and consumption of energy sources expressed in original units, i.e. units recorded in the primary statistics - mainly commercial units. The production of derived energy commodities is recorded on the supply - side of the balance sheets of energy sources, which is not the case in the energy balance sheets. The balance sheets of energy sources also include specifications of input--output and energy consumption in energy conversion industries. The energy balance sheets are based on primary data recorded in the balance sheets of energy sources, here expressed in a common energy unit, TJ. The production of derived energy is recorded in a second flow-step comprising energy turnover in energy conversion and is also specified in complementary input - output tables for energy conversion industries. The following items are shown in the energy balance sheets. 1.1 Inland supply of primary energy; 1.3 Import; 1.4 Export; 1.5 Changes in

Hypsometric amplification and routing moderation of Greenland ice sheet meltwater release

Science.gov (United States)

van As, Dirk; Mikkelsen, Andreas Bech; Holtegaard Nielsen, Morten; Box, Jason E.; Claesson Liljedahl, Lillemor; Lindbäck, Katrin; Pitcher, Lincoln; Hasholt, Bent

2017-06-01

Concurrent ice sheet surface runoff and proglacial discharge monitoring are essential for understanding Greenland ice sheet meltwater release. We use an updated, well-constrained river discharge time series from the Watson River in southwest Greenland, with an accurate, observation-based ice sheet surface mass balance model of the ˜ 12 000 km2 ice sheet area feeding the river. For the 2006-2015 decade, we find a large range of a factor of 3 in interannual variability in discharge. The amount of discharge is amplified ˜ 56 % by the ice sheet's hypsometry, i.e., area increase with elevation. A good match between river discharge and ice sheet surface meltwater production is found after introducing elevation-dependent transit delays that moderate diurnal variability in meltwater release by a factor of 10-20. The routing lag time increases with ice sheet elevation and attains values in excess of 1 week for the upper reaches of the runoff area at ˜ 1800 m above sea level. These multi-day routing delays ensure that the highest proglacial discharge levels and thus overbank flooding events are more likely to occur after multi-day melt episodes. Finally, for the Watson River ice sheet catchment, we find no evidence of meltwater storage in or release from the en- and subglacial environments in quantities exceeding our methodological uncertainty, based on the good match between ice sheet runoff and proglacial discharge.

Active current sheets near the earth's bow shock

International Nuclear Information System (INIS)

Schwartz, S.J.; Kessel, R.L.; Brown, C.C.; Woolliscroft, L.J.C.; Dunlop, M.W.; Farrugia, C.J.; Hall, D.S.

1988-01-01

The authors present here an investigation of active current sheets observed by the AMPTE UK spacecraft near the Earth's bow shock, concentrating on their macroscopic features and geometry. Events selected primarily by flow directions which deviate substantially from the Sun-Earth line show similar characteristics, including their association with an underlying macroscopic current sheet and a hot central region whose flow direction is organized, at least in part, by location relative to the inferred initial intersection point between the current sheet and the bow shock. This region is flanked by edges which, according to a Rankine-Hugoniot analysis, are often fast shocks whose orientation is consistent with that expected if a bulge on the bow shock convected past the spacecraft. They have found the magnetosheath manifestations of these events which they study in detail. They suggest that these events are the direct result of the disruption and reformation of the bow shock by the passage of an interplanetary current sheet, most probably a tangential discontinuity

Financing gas plants using off balance sheet structures

International Nuclear Information System (INIS)

Best, R.J.; Malcolm, V.

1999-01-01

A means by which to finance oil and gas facilities using off balance sheet structures was presented. Off balance sheet facility financing means the sale by an oil and gas producer of a processing and/or transportation facility to a financial intermediary, who under a Management Agreement, appoints the producer as the operator of the facility. The financial intermediary charges a fixed processing fee to the producer and all the benefits and upside of ownership are retained by the producer. This paper deals specifically with a flexible off balance sheet facility financing structure that can be used to make effective use of discretionary capital which is committed to gas processing and to the construction of new gas processing facilities. Off balance sheet financing is an attractive alternative method of ownership that frees up capital that is locked into the facilities while allowing the producer to retain strategic control of the processing facility

Fast imaging of live organisms with sculpted light sheets

Science.gov (United States)

Chmielewski, Aleksander K.; Kyrsting, Anders; Mahou, Pierre; Wayland, Matthew T.; Muresan, Leila; Evers, Jan Felix; Kaminski, Clemens F.

2015-04-01

Light-sheet microscopy is an increasingly popular technique in the life sciences due to its fast 3D imaging capability of fluorescent samples with low photo toxicity compared to confocal methods. In this work we present a new, fast, flexible and simple to implement method to optimize the illumination light-sheet to the requirement at hand. A telescope composed of two electrically tuneable lenses enables us to define thickness and position of the light-sheet independently but accurately within milliseconds, and therefore optimize image quality of the features of interest interactively. We demonstrated the practical benefit of this technique by 1) assembling large field of views from tiled single exposure each with individually optimized illumination settings; 2) sculpting the light-sheet to trace complex sample shapes within single exposures. This technique proved compatible with confocal line scanning detection, further improving image contrast and resolution. Finally, we determined the effect of light-sheet optimization in the context of scattering tissue, devising procedures for balancing image quality, field of view and acquisition speed.

Heat Exchanger Tube to Tube Sheet Joints Corrosion Behavior

Directory of Open Access Journals (Sweden)

M. Iancu

2013-03-01

Full Text Available Paper presents the studies made by the authors above the tube to tube sheet fittings of heat exchanger with fixed covers from hydrofining oil reforming unit. Tube fittings are critical zones for heat exchangers failures. On a device made from material tube and tube sheet at real joints dimensions were establish axial compression force and traction force at which tube is extracted from expanded joint. Were used two shapes joints with two types of fittings surfaces, one with smooth hole of tube sheet and other in which on boring surface we made a groove. From extracted expanded tube zones were made samples for corrosion tests in order to establish the corrosion rate, corrosion potential and corrosion current in working mediums such as hydrofining oil and industrial water at different temperatures. The corrosion rate values and the temperature influence are important to evaluate joints durability and also the results obtained shows that the boring tube sheet shape with a groove on hole tube shape presents a better corrosion behavior then the shape with smooth hole tube sheet.

Interaction of a charge with a thin plasma sheet

International Nuclear Information System (INIS)

Bordag, M.

2007-01-01

The interaction of the electromagnetic field with a two-dimensional plasma sheet intended to describe the pi-electrons of a carbon nanotube or a C 60 molecule is investigated. By first integrating out the displacement field of the plasma or the electromagnetic field, different representations for quantities like the Casimir energy are derived which are shown to be consistent with one another. Starting from the covariant gauge for the electromagnetic field, it is shown that the matching conditions to which the presence of the plasma sheet can be reduced are different from the commonly used ones. The difference in the treatments does not show up in the Casimir force between two parallel sheets, but it is present in the Casimir-Polder force between a charge or a neutral atom and a sheet. At once, since the plasma sheet is a regularization of the conductor boundary conditions, this sheds light on the difference in physics found earlier in the realization of conductor boundary conditions as 'thin' or 'thick' boundary conditions in Phys. Rev. D 70, 085010 (2004)

A Case Study and Balance Sheet Approach to Unemployment.

Science.gov (United States)

Hesketh, Beryl; And Others

1987-01-01

Describes positive and negative aspects of employment and unemployment in a balance sheet framework. Discusses the value of the balance sheet approach in understanding individual differences in reactions to unemployment. (Author/KS)

The Potsdam Parallel Ice Sheet Model (PISM-PIK – Part 2: Dynamic equilibrium simulation of the Antarctic ice sheet

Directory of Open Access Journals (Sweden)

M. A. Martin

2011-09-01

Full Text Available We present a dynamic equilibrium simulation of the ice sheet-shelf system on Antarctica with the Potsdam Parallel Ice Sheet Model (PISM-PIK. The simulation is initialized with present-day conditions for bed topography and ice thickness and then run to steady state with constant present-day surface mass balance. Surface temperature and sub-shelf basal melt distribution are parameterized. Grounding lines and calving fronts are free to evolve, and their modeled equilibrium state is compared to observational data. A physically-motivated calving law based on horizontal spreading rates allows for realistic calving fronts for various types of shelves. Steady-state dynamics including surface velocity and ice flux are analyzed for whole Antarctica and the Ronne-Filchner and Ross ice shelf areas in particular. The results show that the different flow regimes in sheet and shelves, and the transition zone between them, are captured reasonably well, supporting the approach of superposition of SIA and SSA for the representation of fast motion of grounded ice. This approach also leads to a natural emergence of sliding-dominated flow in stream-like features in this new 3-D marine ice sheet model.

BRITICE-CHRONO: Constraining rates and style of marine-influenced ice sheet decay to provide a data-rich playground for ice sheet modellers

Science.gov (United States)

Clark, Chris

2014-05-01

Uncertainty exists regarding the fate of the Antarctic and Greenland ice sheets and how they will respond to forcings from sea level and atmospheric and ocean temperatures. If we want to know more about the mechanisms and rate of change of shrinking ice sheets, then why not examine an ice sheet that has fully disappeared and track its retreat through time? If achieved in enough detail such information could become a data-rich playground for improving the next breed of numerical ice sheet models to be used in ice and sea level forecasting. We regard that the last British-Irish Ice Sheet is a good target for this work, on account of its small size, density of information and with its numerous researchers already investigating it. BRITICE-CHRONO is a large (>45 researchers) NERC-funded consortium project comprising Quaternary scientists and glaciologists who will search the seafloor around Britain and Ireland and parts of the landmass in order to find and extract samples of sand, rock and organic matter that can be dated (OSL; Cosmogenic; 14C) to reveal the timing and rate of change of the collapsing British-Irish Ice Sheet. The purpose is to produce a high resolution dataset on the demise on an ice sheet - from the continental shelf edge and across the marine to terrestrial transition. Some 800 new date assessments will be added to those that already exist. This poster reports on the hypotheses that underpin the work. Data on retreat will be collected by focusing on 8 transects running from the continental shelf edge to a short distance (10s km) onshore and acquiring marine and terrestrial samples for geochronometric dating. The project includes funding for 587 radiocarbon, 140 OSL and 158 TCN samples for surface exposure dating; with sampling accomplished by two research cruises and 16 fieldwork campaigns. Results will reveal the timing and rate of change of ice margin recession for each transect, and combined with existing landform and dating databases, will be

Mountain building and the initiation of the Greenland Ice Sheet

DEFF Research Database (Denmark)

Solgaard, Anne Munck; Bonow, Johan; Langen, Peter Lang

2013-01-01

The effects of a new hypothesis about mountain building in Greenland on ice sheet initiation are investigated using an ice sheet model in combination with a climate model. According to this hypothesis, low-relief landscapes near sea level characterised Greenland in Miocene times until two phases...... superimposed by cold and warm excursions. The modelling results show that no ice initiates in the case of the low-lying and almost flat topography prior to the uplifts. However, the results demonstrate a significant ice sheet growth in response to the orographically induced increase in precipitation....... Under conditions that are colder than the present, the ice can overcome the Föhn effect, flow into the interior and form a coherent ice sheet. The results thus indicate that the Greenland Ice Sheet of today is a relict formed under colder conditions. The modelling results are consistent...

Two-and-one-half-dimensional magnetohydrodynamic simulations of the plasma sheet in the presence of oxygen ions: The plasma sheet oscillation and compressional Pc 5 waves

International Nuclear Information System (INIS)

Lu Li; Liu Zhenxing; Cao Jinbin

2002-01-01

Two-and-one-half-dimensional magnetohydrodynamic simulations of the multicomponent plasma sheet with the velocity curl term in the magnetic equation are represented. The simulation results can be summarized as follows: (1) There is an oscillation of the plasma sheet with the period on the order of 400 s (Pc 5 range); (2) the magnetic equator is a node of the magnetic field disturbance; (3) the magnetic energy integral varies antiphase with the internal energy integral; (4) disturbed waves have a propagating speed on the order of 10 km/s earthward; (5) the abundance of oxygen ions influences amplitude, period, and dissipation of the plasma sheet oscillation. It is suggested that the compressional Pc 5 waves, which are observed in the plasma sheet close to the magnetic equator, may be caused by the plasma sheet oscillation, or may be generated from the resonance of the plasma sheet oscillation with some Pc 5 perturbation waves coming from the outer magnetosphere

Mirage effect from thermally modulated transparent carbon nanotube sheets.

Science.gov (United States)

Aliev, Ali E; Gartstein, Yuri N; Baughman, Ray H

2011-10-28

The single-beam mirage effect, also known as photothermal deflection, is studied using a free-standing, highly aligned carbon nanotube aerogel sheet as the heat source. The extremely low thermal capacitance and high heat transfer ability of these transparent forest-drawn carbon nanotube sheets enables high frequency modulation of sheet temperature over an enormous temperature range, thereby providing a sharp, rapidly changing gradient of refractive index in the surrounding liquid or gas. The advantages of temperature modulation using carbon nanotube sheets are multiple: in inert gases the temperature can reach > 2500 K; the obtained frequency range for photothermal modulation is ~100 kHz in gases and over 100 Hz in high refractive index liquids; and the heat source is transparent for optical and acoustical waves. Unlike for conventional heat sources for photothermal deflection, the intensity and phase of the thermally modulated beam component linearly depends upon the beam-to-sheet separation over a wide range of distances. This aspect enables convenient measurements of accurate values for thermal diffusivity and the temperature dependence of refractive index for both liquids and gases. The remarkable performance of nanotube sheets suggests possible applications as photo-deflectors and for switchable invisibility cloaks, and provides useful insights into their use as thermoacoustic projectors and sonar. Visibility cloaking is demonstrated in a liquid.

Hanford Site Treated Effluent Disposal Facility process flow sheet

International Nuclear Information System (INIS)

Bendixsen, R.B.

1993-04-01

This report presents a novel method of using precipitation, destruction and recycle factors to prepare a process flow sheet. The 300 Area Treated Effluent Disposal Facility (TEDF) will treat process sewer waste water from the 300 Area of the Hanford Site, located near Richland, Washington, and discharge a permittable effluent flow into the Columbia River. When completed and operating, the TEDF effluent water flow will meet or exceed water quality standards for the 300 Area process sewer effluents. A preliminary safety analysis document (PSAD), a preconstruction requirement, needed a process flow sheet detailing the concentrations of radionuclides, inorganics and organics throughout the process, including the effluents, and providing estimates of stream flow quantities, activities, composition, and properties (i.e. temperature, pressure, specific gravity, pH and heat transfer rates). As the facility begins to operate, data from process samples can be used to provide better estimates of the factors, the factors can be entered into the flow sheet and the flow sheet will estimate more accurate steady state concentrations for the components. This report shows how the factors were developed and how they were used in developing a flow sheet to estimate component concentrations for the process flows. The report concludes with how TEDF sample data can improve the ability of the flow sheet to accurately predict concentrations of components in the process

Symmetry breaking bifurcations of a current sheet

International Nuclear Information System (INIS)

Parker, R.D.; Dewar, R.L.; Johnson, J.L.

1988-08-01

Using a time evolution code with periodic boundary conditions, the viscoresistive hydromagnetic equations describing an initially static, planar current sheet with large Lundquist number have been evolved for times long enough to reach a steady state. A cosh 2 x resistivity model was used. For long periodicity lengths, L p , the resistivity gradient drives flows which cause forced reconnection at X point current sheets. Using L p as a bifurcation parameter, two new symmetry breaking bifurcations were found - a transition to an asymmetric island chain with nonzero, positive or negative phase velocity, and a transition to a static state with alternating large and small islands. These states are reached after a complex transient behavior which involves a competition between secondary current sheet instability and coalescence. 31 refs., 6 figs

Flat-plate solar array project. Volume 3: Silicon sheet: Wafers and ribbons

Science.gov (United States)

Briglio, A.; Dumas, K.; Leipold, M.; Morrison, A.

1986-01-01

The primary objective of the Silicon Sheet Task of the Flat-Plate Solar Array (FSA) Project was the development of one or more low cost technologies for producing silicon sheet suitable for processing into cost-competitive solar cells. Silicon sheet refers to high purity crystalline silicon of size and thickness for fabrication into solar cells. Areas covered in the project were ingot growth and casting, wafering, ribbon growth, and other sheet technologies. The task made and fostered significant improvements in silicon sheet including processing of both ingot and ribbon technologies. An additional important outcome was the vastly improved understanding of the characteristics associated with high quality sheet, and the control of the parameters required for higher efficiency solar cells. Although significant sheet cost reductions were made, the technology advancements required to meet the task cost goals were not achieved.

Irish Ice Sheet dynamics during deglaciation of the central Irish Midlands: Evidence of ice streaming and surging from airborne LiDAR

Science.gov (United States)

Delaney, Catherine A.; McCarron, Stephen; Davis, Stephen

2018-04-01

High resolution digital terrain models (DTMs) generated from airborne LiDAR data and supplemented by field evidence are used to map glacial landform assemblages dating from the last glaciation (Midlandian glaciation; OI stages 2-3) in the central Irish Midlands. The DTMs reveal previously unrecognised low-amplitude landforms, including crevasse-squeeze ridges and mega-scale glacial lineations overprinted by conduit fills leading to ice-marginal subaqueous deposits. We interpret this landform assemblage as evidence for surging behaviour during ice recession. The data indicate that two separate phases of accelerated ice flow were followed by ice sheet stagnation during overall deglaciation. The second surge event was followed by a subglacial outburst flood, forming an intricate esker and crevasse-fill network. The data provide the first clear evidence that ice flow direction was eastward along the eastern watershed of the Shannon River basin, at odds with previous models, and raise the possibility that an ice stream existed in this area. Our work demonstrates the potential for airborne LiDAR surveys to produce detailed paleoglaciological reconstructions and to enhance our understanding of complex palaeo-ice sheet dynamics.

Teacher Perceptions of Their Curricular and Pedagogical Shifts: Outcomes of a Project-Based Model of Teacher Professional Development in the Next Generation Science Standards

Directory of Open Access Journals (Sweden)

David J. Shernoff

2017-06-01

Full Text Available In this study, we conducted a model of teacher professional development (PD on the alignment of middle and high school curricula and instruction to the Next Generation Science Standards (NGSSs, and evaluated the impact of the PD on teacher participants’ development. The PD model included a 4-day summer academy emphasizing project-based learning (PBL in the designing of NGSS-aligned curricula and instruction, as well as monthly follow-up Professional Learning Community meetings throughout the year providing numerous opportunities for teachers to develop and implement lesson plans, share results of lesson writing and implementation (successes and challenges, provide mutual feedback, and refine curricula and assessments. Following the summer academy, six female teachers were interviewed about their current conceptualizations of NGSS, the extent of curricular shifts made that are required by NGSS, their self-perceptions regarding their level of accomplishment in curriculum writing, and the benefits of the PD in reaching their goals related to NGSS. Interviews were supplemented with an analysis of lesson plans written while participating in the PD program. The interviewed teachers suggested that they had made important conceptual and pedagogical shifts required by NGSS as they participated in the PD, and also noted a variety of challenges as they made this shift. While all teachers were relative novices at NGSS curriculum writing before the PD, most of the teachers interviewed felt that they had achieved the status of an “accomplished novice” following the summer academy. An analysis of their written lessons suggested a great range in the extent to which teachers effectively applied their understanding of NGSS to write lessons aligned to NGSS. Interviewed teachers believed that the PD model was helpful to their development as science teachers, and all reported that there were no aspects of the PD that were not helpful. Even though most teachers

Machine Shop Suggested Job and Task Sheets. Part I. 25 Elementary Jobs.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of elementary job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-five simple machine shop job sheets are included. Some or all of this material is provided for each job sheet: an introductory sheet with aim, checking…

Current state and future perspectives on coupled ice-sheet - sea-level modelling

Science.gov (United States)

de Boer, Bas; Stocchi, Paolo; Whitehouse, Pippa L.; van de Wal, Roderik S. W.

2017-08-01

The interaction between ice-sheet growth and retreat and sea-level change has been an established field of research for many years. However, recent advances in numerical modelling have shed new light on the precise interaction of marine ice sheets with the change in near-field sea level, and the related stability of the grounding line position. Studies using fully coupled ice-sheet - sea-level models have shown that accounting for gravitationally self-consistent sea-level change will act to slow down the retreat and advance of marine ice-sheet grounding lines. Moreover, by simultaneously solving the 'sea-level equation' and modelling ice-sheet flow, coupled models provide a global field of relative sea-level change that is consistent with dynamic changes in ice-sheet extent. In this paper we present an overview of recent advances, possible caveats, methodologies and challenges involved in coupled ice-sheet - sea-level modelling. We conclude by presenting a first-order comparison between a suite of relative sea-level data and output from a coupled ice-sheet - sea-level model.

On the structure of the magnetotail current sheet

International Nuclear Information System (INIS)

Ashour-Abdalla, M.; Peroomian, V.; Richard, R.L.; Zelenyi, L.M.

1993-01-01

Results from modeling ion distribution functions in a two-dimensional reduction of the Tsyganenko magnetic field model have enabled the authors to calculate the full ion pressure tensor inside the model magnetotail. A thin current sheet is formed in the distant tail and the pressure tensor within this sheet has significant off-diagonal terms. These terms resulting from quasiadiabatic ion trajectories create azimuthally asymmetric distribution functions which are capable of maintaining stress-balance. Outside the current sheet the off-diagonal terms disappear and moderate anisotropy builds up with P perpendicular/P parallel ∼ 0.8. Closer to the Earth rapid isotropization of the distribution occurs

Greenland Ice Sheet Surface Temperature, Melt, and Mass Loss: 2000-2006

Science.gov (United States)

Hall, Dorothy K.; Williams, Richard S., Jr.; Luthcke, Scott B.; DiGirolamo, Nocolo

2007-01-01

Extensive melt on the Greenland Ice Sheet has been documented by a variety of ground and satellite measurements in recent years. If the well-documented warming continues in the Arctic, melting of the Greenland Ice Sheet will likely accelerate, contributing to sea-level rise. Modeling studies indicate that an annual or summer temperature rise of 1 C on the ice sheet will increase melt by 20-50% therefore, surface temperature is one of the most important ice-sheet parameters to study for analysis of changes in the mass balance of the ice-sheet. The Greenland Ice Sheet contains enough water to produce a rise in eustatic sea level of up to 7.0 m if the ice were to melt completely. However, even small changes (centimeters) in sea level would cause important economic and societal consequences in the world's major coastal cities thus it is extremely important to monitor changes in the ice-sheet surface temperature and to ultimately quantify these changes in terms of amount of sea-level rise. We have compiled a high-resolution, daily time series of surface temperature of the Greenland Ice Sheet, using the I-km resolution, clear-sky land-surface temperature (LST) standard product from the Moderate-Resolution Imaging Spectroradiometer (MODIS), from 2000 - 2006. We also use Gravity Recovery and Climate Experiment (GRACE) data, averaged over 10-day periods, to measure change in mass of the ice sheet as it melt and snow accumulates. Surface temperature can be used to determine frequency of surface melt, timing of the start and the end of the melt season, and duration of melt. In conjunction with GRACE data, it can also be used to analyze timing of ice-sheet mass loss and gain.

Research Status on the Heterogeneous Sheet Connection Forming Technology

Directory of Open Access Journals (Sweden)

SHI Wen-yong

2017-04-01

Full Text Available The heterogeneous sheet connection forming is one of the effective ways to realize lightweight in many fields，such as equipment manufacturing and transportation. However, there are obvious differences in the material properties，when using the traditional connection methods，there is a certain technical bottlenecks. In this paper, the technological characteristics and research status of the welding method and mechanical connection method are discussed in detail，such as the TIC welding and the laser welding. The advantages and development potential of the technology are introduced in the field of the heterogeneous sheet connection，in combination with the industry development and the use demand，the development of the heterogeneous sheet connection technology is expected，to provide the technical support for the research and development of new heterogeneous sheet connection technology.

1998 energy balance sheet of France

International Nuclear Information System (INIS)

Anon.

1999-01-01

This paper summarizes the results of the energy balance sheet of France for the year 1998 according to the data published by the energy observatory from the general direction of energy and raw materials (DGEMP) and according to the press communication given by C. Pierret, French state secretary of the industry. The following points are commented: the energy balance sheet (national production and energy independence, the energy shares in the consumption), the decay of the energy bill, and the details of the bill by energy type. (J.S.)

Physics of the magnetotail current sheet

International Nuclear Information System (INIS)

Chen, J.

1993-01-01

The Earth's magnetotail plays an important role in the solar-wind--magnetosphere coupling. At the midplane of the magnetotail is a current sheet where the dominant magnetic field component reverses sign. The charged particle motion in and near the current sheet is collisionless and nonintegrable, exhibiting chaotic scattering. The current understanding of the dynamical properties of the charged particle motion is discussed. In particular, the relationships between particle dynamics and global attributes of the system are elucidated. Geometrical properties of the phase space determine important physical observables on both micro- and macroscales

Periodic folding of viscous sheets

Science.gov (United States)

Ribe, Neil M.

2003-09-01

The periodic folding of a sheet of viscous fluid falling upon a rigid surface is a common fluid mechanical instability that occurs in contexts ranging from food processing to geophysics. Asymptotic thin-layer equations for the combined stretching-bending deformation of a two-dimensional sheet are solved numerically to determine the folding frequency as a function of the sheet’s initial thickness, the pouring speed, the height of fall, and the fluid properties. As the buoyancy increases, the system bifurcates from “forced” folding driven kinematically by fluid extrusion to “free” folding in which viscous resistance to bending is balanced by buoyancy. The systematics of the numerically predicted folding frequency are in good agreement with laboratory experiments.

Modelling of aluminium sheet forming at elevated temperatures

NARCIS (Netherlands)

van den Boogaard, Antonius H.; Huetink, Han

2004-01-01

The formability of Al–Mg sheet can be improved considerably, by increasing the temperature. By heating the sheet in areas with large shear strains, but cooling it on places where the risk of necking is high, the limiting drawing ratio can be increased to values above 2.5. At elevated temperatures,

On normal modes of gas sheets and discs

International Nuclear Information System (INIS)

Drury, L.O'C.

1980-01-01

A method is described for calculating the reflection and transmission coefficients characterizing normal modes of the Goldreich-Lynden-Bell gas sheet. Two families of gas discs without self-gravity for which the normal modes can be found analytically are given and used to illustrate the validity of the sheet approximation. (author)

Hypsometric amplification and routing moderation of Greenland ice sheet meltwater release

Directory of Open Access Journals (Sweden)

D. van As

2017-06-01

Full Text Available Concurrent ice sheet surface runoff and proglacial discharge monitoring are essential for understanding Greenland ice sheet meltwater release. We use an updated, well-constrained river discharge time series from the Watson River in southwest Greenland, with an accurate, observation-based ice sheet surface mass balance model of the  ∼  12 000 km2 ice sheet area feeding the river. For the 2006–2015 decade, we find a large range of a factor of 3 in interannual variability in discharge. The amount of discharge is amplified  ∼  56 % by the ice sheet's hypsometry, i.e., area increase with elevation. A good match between river discharge and ice sheet surface meltwater production is found after introducing elevation-dependent transit delays that moderate diurnal variability in meltwater release by a factor of 10–20. The routing lag time increases with ice sheet elevation and attains values in excess of 1 week for the upper reaches of the runoff area at  ∼  1800 m above sea level. These multi-day routing delays ensure that the highest proglacial discharge levels and thus overbank flooding events are more likely to occur after multi-day melt episodes. Finally, for the Watson River ice sheet catchment, we find no evidence of meltwater storage in or release from the en- and subglacial environments in quantities exceeding our methodological uncertainty, based on the good match between ice sheet runoff and proglacial discharge.

Nonlinear Dynamics of Non-uniform Current-Vortex Sheets in Magnetohydrodynamic Flows

Science.gov (United States)

Matsuoka, C.; Nishihara, K.; Sano, T.

2017-04-01

A theoretical model is proposed to describe fully nonlinear dynamics of interfaces in two-dimensional MHD flows based on an idea of non-uniform current-vortex sheet. Application of vortex sheet model to MHD flows has a crucial difficulty because of non-conservative nature of magnetic tension. However, it is shown that when a magnetic field is initially parallel to an interface, the concept of vortex sheet can be extended to MHD flows (current-vortex sheet). Two-dimensional MHD flows are then described only by a one-dimensional Lagrange parameter on the sheet. It is also shown that bulk magnetic field and velocity can be calculated from their values on the sheet. The model is tested by MHD Richtmyer-Meshkov instability with sinusoidal vortex sheet strength. Two-dimensional ideal MHD simulations show that the nonlinear dynamics of a shocked interface with density stratification agrees fairly well with that for its corresponding potential flow. Numerical solutions of the model reproduce properly the results of the ideal MHD simulations, such as the roll-up of spike, exponential growth of magnetic field, and its saturation and oscillation. Nonlinear evolution of the interface is found to be determined by the Alfvén and Atwood numbers. Some of their dependence on the sheet dynamics and magnetic field amplification are discussed. It is shown by the model that the magnetic field amplification occurs locally associated with the nonlinear dynamics of the current-vortex sheet. We expect that our model can be applicable to a wide variety of MHD shear flows.

Window-dressing in German interwar balance sheets

OpenAIRE

Mark Spoerer

1998-01-01

German accounting rules value assets and liabilities asymmetrically and thus lead to grossly distorted balance sheets. In the interwar debate on a reform of disclosure regulation, financial experts considered the (undisclosed) tax balance sheet, which had to be drawn up separately for the corporate tax assessment, as a paradigm for adequate financial disclosure. However, due to tax secrecy thay were barred from analyzing tax documents. Using archival evidence, we analyz...

Geometry task & drill sheets : grades 6-8

CERN Document Server

Rosenberg, Mary

2011-01-01

For grades 6-8, our Common Core State Standards-based combined resource meets the geometry concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills.

Estimating the future ice sheet hydropower potential in Paakitsoq, Ilulissat, West Greenland

DEFF Research Database (Denmark)

Ahlstrøm, Andreas P.; Mottram, R.H.; Nielsen, C.

2008-01-01

sheet has emphasized the risk of sudden changes in catchment supply. In this study, we present a thorough investigation of hydropower feasibility at the Paakitsoq basin, near Ilulissat in West Greenland. The catchment is completely dominated by the Greenland ice sheet which provides large quantities...... of meltwater during the summer season. However, geometrical changes in the ice sheet, for example due to a retreat or an advance of the ice sheet margin, could change the hydrological catchment within the ice sheet. Such a change would have a devastating economical impact as a hydropower plant is a significant...... long-term investment for an Arctic community of modest population. Here we present a new bedrock and surface map of the Paakitsoq/Swiss Camp part of the Greenland ice sheet and a prediction of the future discharge up to 2080 AD using regional climate model output, dynamic ice sheet modelling...

Solar wind and substorm excitation of the wavy current sheet

Directory of Open Access Journals (Sweden)

C. Forsyth

2009-06-01

Full Text Available Following a solar wind pressure pulse on 3 August 2001, GOES 8, GOES 10, Cluster and Polar observed dipolarizations of the magnetic field, accompanied by an eastward expansion of the aurora observed by IMAGE, indicating the occurrence of two substorms. Prior to the first substorm, the motion of the plasma sheet with respect to Cluster was in the Z_GSM direction. Observations following the substorms show the occurrence of current sheet waves moving predominantly in the −Y_GSM direction. Following the second substorm, the current sheet waves caused multiple current sheet crossings of the Cluster spacecraft, previously studied by Zhang et al. (2002. We further this study to show that the velocity of the current sheet waves was similar to the expansion velocity of the substorm aurora and the expansion of the dipolarization regions in the magnetotail. Furthermore, we compare these results with the current sheet wave models of Golovchanskaya and Maltsev (2005 and Erkaev et al. (2008. We find that the Erkaev et al. (2008 model gives the best fit to the observations.

The Efficacy of a Silicone Sheet in Postoperative Scar Management.

Science.gov (United States)

Kim, Jin Sam; Hong, Joon Pio; Choi, Jong Woo; Seo, Dong Kyo; Lee, Eun Sook; Lee, Ho Seong

2016-09-01

Silicone gel sheeting has been introduced to prevent scarring, but objective evidence for its usefulness in scar healing is limited. Therefore, the authors' objective was to examine the effectiveness of silicone gel sheeting by randomly applying it to only unilateral scars from a bilateral hallux valgus surgery with symmetrical closure. In a prospective randomized, blinded, intraindividual comparison study, the silicone gel sheeting was applied to 1 foot of a hallux valgus incision scar (an experiment group) for 12 weeks upon removal of the stitches, whereas the symmetrical scar from the other foot was left untreated (a control group). The scars were evaluated at 4 and 12 weeks after the silicon sheet application. The Vancouver Scar Scale was used to measure the vascularity, pigmentation, pliability, height, and length of the scars. Adverse effects were also evaluated, and they included pain, itchiness, rash, erythema, and skin softening. At weeks 4 and 12, the experiment group scored significantly better on the Vancouver Scar Scale in all items, except length (P sheet does not cause adverse effects (P sheet application did show a significant improvement in prevention of postoperative scarring.

1970-1997 energy balance-sheets

International Nuclear Information System (INIS)

1998-01-01

The aim of this document is to bring together a consistent and harmonized set of statistical data on energy economics in the French territory. The information is based on the global and structural approach of the different energy balance-sheets published between 1970 and 1997. The first chapter gives a general idea of the energy situation of the passed year and outlines the evolution of the main aggregates (production, primary and final consumption etc..) comparatively to those of the general economy. The second chapter is devoted to the history of energy economics. Time series of indicators and diagrams allow to precise the structural modifications that occurred during the last decades. The main transformations in the national energy production and the development of the different energy sources in the industry, the residential and tertiary sectors and in the transportation sector are described too. The third chapter gives numerical data on energy for the last 28 years using the common Mtpe unit (million of tons of petroleum equivalent). These balance sheets are based on new energy keeping methods and use identical equivalence coefficients. The last chapter presents the energy balance sheets for the last three years, using the proper units for coal, petroleum, gas and electricity. (J.S.)

Effect of Fe, Co, Si and Ge impurities on optical properties of graphene sheet

International Nuclear Information System (INIS)

Kheyri, A.; Nourbakhsh, Z.; Darabi, E.

2016-01-01

The electronic and linear optical properties of pure graphene and impurity-graphene (with Fe, Co, Si and Ge impurities) sheets are investigated by using the full potential linear augmented plane wave plus local orbital (FPLAPW + lo) in the framework of the density functional theory (DFT). The calculated results are obtained within the generalized gradient approximation using the Perdew–Burke–Ernzerhof scheme in the presence of spin-orbit interaction. The band structure, partial electron density of states, dielectric function, absorption coefficient, optical conductivity, extinction index, energy loss function, reflectivity and the refraction index of these sheets for parallel and perpendicular electromagnetic wave polarization to sheet are investigated. The optical conductivity of Si-graphene and Ge-graphene sheets for the parallel electromagnetic wave polarization to the sheet starts with a gap about 0.4 eV confirms that these sheets have semiconductor behavior. Also the optical spectra of these sheets are anisotropic along these two wave polarizations. The dielectric function in the static limit of pure graphene sheet for perpendicular electromagnetic wave polarization to sheet does not significant change in the presence of Si, Ge, Fe and Co impurities. The static refractive index of Fe-graphene and Co-graphene sheets for parallel electromagnetic wave polarization to sheet is much larger than the corresponding value of pure graphene sheet. - Highlights: • Graphene sheet with Fe and Co impurities is metal. • Graphene sheet with Si and Ge impurities is semiconductor with 0.2 eV energy band gap. • These sheets optical spectra have metallic behavior for perpendicular polarization. • These sheets optical spectra have semiconductor behavior for parallel polarization. • Graphene sheet with Si and Ge impurities can use for optoelectronic devices.

Effect of Fe, Co, Si and Ge impurities on optical properties of graphene sheet

Energy Technology Data Exchange (ETDEWEB)

Kheyri, A. [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Nourbakhsh, Z., E-mail: z.nourbakhsh@sci.ui.ac.ir [Physics Department, Faculty of Science, University of Isfahan, Isfahan (Iran, Islamic Republic of); Darabi, E. [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

2016-08-01

The electronic and linear optical properties of pure graphene and impurity-graphene (with Fe, Co, Si and Ge impurities) sheets are investigated by using the full potential linear augmented plane wave plus local orbital (FPLAPW + lo) in the framework of the density functional theory (DFT). The calculated results are obtained within the generalized gradient approximation using the Perdew–Burke–Ernzerhof scheme in the presence of spin-orbit interaction. The band structure, partial electron density of states, dielectric function, absorption coefficient, optical conductivity, extinction index, energy loss function, reflectivity and the refraction index of these sheets for parallel and perpendicular electromagnetic wave polarization to sheet are investigated. The optical conductivity of Si-graphene and Ge-graphene sheets for the parallel electromagnetic wave polarization to the sheet starts with a gap about 0.4 eV confirms that these sheets have semiconductor behavior. Also the optical spectra of these sheets are anisotropic along these two wave polarizations. The dielectric function in the static limit of pure graphene sheet for perpendicular electromagnetic wave polarization to sheet does not significant change in the presence of Si, Ge, Fe and Co impurities. The static refractive index of Fe-graphene and Co-graphene sheets for parallel electromagnetic wave polarization to sheet is much larger than the corresponding value of pure graphene sheet. - Highlights: • Graphene sheet with Fe and Co impurities is metal. • Graphene sheet with Si and Ge impurities is semiconductor with 0.2 eV energy band gap. • These sheets optical spectra have metallic behavior for perpendicular polarization. • These sheets optical spectra have semiconductor behavior for parallel polarization. • Graphene sheet with Si and Ge impurities can use for optoelectronic devices.

Botanical supplements: detecting the transition from ingredients to supplements

Science.gov (United States)

Methods were developed using flow injection mass spectrometry (FIMS) and chemometrics for the comparison of spectral similarities and differences of 3 botanical ingredients and their supplements: Echinacea purpurea aerial samples and solid and liquid supplements, E. purpurea root samples and solid s...

Bracing system of the reflecting sheets making up an insulating pile

International Nuclear Information System (INIS)

Carr, R.W.

1976-01-01

In order to reduce heat and radiation losses, the body of nuclear reactors and the connected pipe work are encased in reflecting and insulating piles of thin spaced sheets of aluminium or stainless steel. These spaced sheets are then encased in thicker and more solid internal and external shells. The piles and shells are generally shaped to follow the contour of the reactor and connected piping. It is therefore necessary to have available a study bracing system to keep the pile intact during the various handling and assembly operations. The fastening system must also exert an effect on the edge of the pile to prevent the sheets making it up from shifting in relation to each other. The description is given of a fastening system that includes an oblong section to be fitted along the edges of the piles up sheets; bracing substantially perpendicular to the oblong section, to space the sheets of the stack in pairs; and a maintaining system, normally perpendicular to the oblong section, to enable the fastener to be clipped to the edge of the sheets by bending it around the edge of each sheet of the pile [fr

Biobeam—Multiplexed wave-optical simulations of light-sheet microscopy

Science.gov (United States)

Weigert, Martin; Bundschuh, Sebastian T.

2018-01-01

Sample-induced image-degradation remains an intricate wave-optical problem in light-sheet microscopy. Here we present biobeam, an open-source software package that enables simulation of operational light-sheet microscopes by combining data from 105–106 multiplexed and GPU-accelerated point-spread-function calculations. The wave-optical nature of these simulations leads to the faithful reproduction of spatially varying aberrations, diffraction artifacts, geometric image distortions, adaptive optics, and emergent wave-optical phenomena, and renders image-formation in light-sheet microscopy computationally tractable. PMID:29652879

Bringing Sheet Music to Life: My Experiences with OMR

Directory of Open Access Journals (Sweden)

Andrew Bullen

2008-06-01

Full Text Available This article describes the process of digitizing sheet music celebrating Pullman porters and rail travel from the 1870s-1920s. The process involves 1 digitizing sheet music, 2 running the digitized sheet music through an Optical Musical Recognition (OMR software package, 3cleaning up the resulting file, 4 converting it into an .mp3/MIDI file, and 5 tweaking it to use the voices/instruments of a music editing software program. The pros and cons of some popular OMR programs are discussed.

Interactions between two beta-sheets. Energetics of beta/beta packing in proteins.

Science.gov (United States)

Chou, K C; Némethy, G; Rumsey, S; Tuttle, R W; Scheraga, H A

1986-04-20

The analysis of the interactions between regularly folded segments of the polypeptide chain contributes to an understanding of the energetics of protein folding. Conformational energy-minimization calculations have been carried out to determine the favorable ways of packing two right-twisted beta-sheets. The packing of two five-stranded beta-sheets was investigated, with the strands having the composition CH3CO-(L-Ile)6-NHCH3 in one beta-sheet and CH3CO-(L-Val)6-NHCH3 in the other. Two distinct classes of low-energy packing arrangements were found. In the class with lowest energies, the strands of the two beta-sheets are aligned nearly parallel (or antiparallel) with each other, with a preference for a negative orientation angle, because this arrangement corresponds to the best complementary packing of the two twisted saddle-shaped beta-sheets. In the second class, with higher interaction energies, the strands of the two beta-sheets are oriented nearly perpendicular to each other. While the surfaces of the two beta-sheets are not complementary in this arrangement, there is good packing between the corner of one beta-sheet and the interior part of the surface of the other, resulting in a favorable energy of packing. Both classes correspond to frequently observed orientations of beta-sheets in proteins. In proteins, the second class of packing is usually observed when the two beta-sheets are covalently linked, i.e. when a polypeptide strand passes from one beta-sheet to the other, but we have shown here that a large contribution to the stabilization of this packing arrangement arises from noncovalent interactions.

Using REE tracers to measure sheet erosion changing to rill erosion

International Nuclear Information System (INIS)

Liu Puling; Xue Yazhou; Song Wei; Wang Mingyi; Ju Tongjun

2004-01-01

Rare Earth Elements (REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different rare earth elements of different soil depth across a slope in an indoor plot, two simulated rainfalls were applied to study the change of erosion type and the rill erosion process. The results indicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happens after rill erosion appears. Accumulated sheet and rill erosion amounts increase with the rainfalls time. The percentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of the rainfalls, the total rill erosion amounts are 4-5 times more than sheet erosion. In this paper, a new REE tracer method was used to quantitatively distinguish sheet and rill erosion amounts. The new REE tracer method should be useful to future studying of erosion processes on slope lands. (authors)

Description and classification of uranium oxide hydrate sheet topologies

International Nuclear Information System (INIS)

Miller, M.L.; Burns, P.C.; Ewing, R.C.; Finch, R.J.

1996-01-01

The uranyl oxide hydrates (UOH) are important corrosion products of uraninite and UO 2 in spent nuclear fuel under oxidizing conditions. However, the systematics of the crystal chemistry, thermodynamic parameters, and solubilities of this mineral group are poorly understood. With the exception of the synthetic UO 2 (OH) 2 polymorphs, all UOH crystal structures are based on sheets of edge-sharing 5 and 4-coordinated uranyl dipyramids. This structural similarity suggests that it is possible to develop a model by which to estimate the thermodynamic behavior of UOHs from data on structural endmember phases. Toward this end, a method of quantitatively describing all known UOH sheets has been developed. Only four structural unit chains are required to construct the uranyl oxide hydrate sheets (as well as the structurally similar U 3 O 8 sheets). The H-chain is restricted to α-UO 2 (OH) 2 and is made up of hexagonally coordinated uranyl ions sharing opposing edges. The arrowhead chain composed of pentagonal dipyramids sharing edges and alternating with trigonal vacancies is present in all other UOH sheets. These arrowhead chains are directed and can occur in both an Up-arrow and Down-arrow sense within a single sheet. The P-chain consists of edge-sharing pentagonal dipyramids forming a zigzag chain. The P-chain is flanked on both sides by arrowhead chains of the same sense. The remaining structural unit is a discontinuous chain of rhombic dipyramids. This R-chain is produced when nested adjacent Up-arrow and Down-arrow arrowhead chains are translated by a diagonal shift. This chain occurs in sheets which contain only 4-coordinate uranyl ion and those containing both 4- and 5-coordinate uranyl ions

Patterns through elastic instabilities, from thin sheets to twisted ribbons

Science.gov (United States)

Damman, Pascal

Sheets embedded in a given shape by external forces store the exerted work in elastic deformations. For pure tensile forces, the work is stored as stretching energy. When the forces are compressive, several ways to store the exerted work, combining stretching and bending deformations can be explored. For large deflections, the ratio of bending, Eh3ζ2 /L4 and stretching, Ehζ4 /L4 energies, suggests that strain-free solutions should be favored for thin sheets, provided ζ2 >>h2 (where E , ζ , Land h are the elastic modulus, the deflection, a characteristic sheet size and its thickness). For uniaxially constrained sheets deriving from the Elastica, strain-free solutions are obvious, i.e., buckles, folds or wrinkles grow to absorb the stress of compression. In contrast, crumpled sheets exhibit ``origami-like'' solutions usually described as an assembly of flat polygonal facets delimitated by ridges focusing strains are observed. This type of solutions is particularly interesting since a faceted morphology is isometric to the undeformed sheet, except at those narrow ridges. In some cases however, the geometric constraints imposed by the external forces do not allow solutions with negligible strain in the deformed state. For instance, considering a circular sheet on a small drop, so thin that bending becomes negligible, i.e., Eh3 / γL2 geometry and a competition between various energy terms, involving stretching and bending modes.

Ni-Flash-Coated Galvannealed Steel Sheet with Improved Properties

Science.gov (United States)

Pradhan, D.; Dutta, M.; Venugopalan, T.

2016-11-01

In the last several years, automobile industries have increasingly focused on galvannealed (GA) steel sheet due to their superior properties such as weldability, paintability and corrosion protection. To improve the properties further, different coatings on GA have been reported. In this context, an electroplating process (flash coating) of bright and adherent Ni plating was developed on GA steel sheet for covering the GA defects and enhancing the performances such as weldability, frictional behavior, corrosion resistance and phosphatability. For better illustration, a comparative study with bare GA steel sheet has also been carried out. The maximum electroplating current density of 700 A/m2 yielded higher cathode current efficiency of 95-98%. The performances showed that Ni-coated (coating time 5-7 s) GA steel sheet has better spot weldability, lower dynamic coefficient of friction (0.07 in lubrication) and three times more corrosion resistance compared to bare GA steel sheet. Plate-like crystal of phosphate coating with size of 10-25 µm was obtained on the Ni-coated GA. The main phase in the phosphate compound was identified as hopeite (63.4 wt.%) along with other phases such as spencerite (28.3 wt.%) and phosphophyllite (8.3 wt.%).

Low cost light-sheet microscopy for whole brain imaging

Science.gov (United States)

Kumar, Manish; Nasenbeny, Jordan; Kozorovitskiy, Yevgenia

2018-02-01

Light-sheet microscopy has evolved as an indispensable tool in imaging biological samples. It can image 3D samples at fast speed, with high-resolution optical sectioning, and with reduced photobleaching effects. These properties make light-sheet microscopy ideal for imaging fluorophores in a variety of biological samples and organisms, e.g. zebrafish, drosophila, cleared mouse brains, etc. While most commercial turnkey light-sheet systems are expensive, the existing lower cost implementations, e.g. OpenSPIM, are focused on achieving high-resolution imaging of small samples or organisms like zebrafish. In this work, we substantially reduce the cost of light-sheet microscope system while targeting to image much larger samples, i.e. cleared mouse brains, at single-cell resolution. The expensive components of a lightsheet system - excitation laser, water-immersion objectives, and translation stage - are replaced with an incoherent laser diode, dry objectives, and a custom-built Arduino-controlled translation stage. A low-cost CUBIC protocol is used to clear fixed mouse brain samples. The open-source platforms of μManager and Fiji support image acquisition, processing, and visualization. Our system can easily be extended to multi-color light-sheet microscopy.

Research on Computer Integrated Manufacturing of Sheet Metal Parts for Lithium Battery

Directory of Open Access Journals (Sweden)

Pan Wei-Min

2016-01-01

Full Text Available Lithium battery has been widely used as the main driving force of the new energy vehicle in recent years. Sheet metal parts are formed by means of pressure forming techniques with the characteristics of light weight, small size and high structural strength. The sheet metal forming has higher productivity and material utilization than the mechanical cutting, therefore sheet metal parts are widely used in many fields, such as modern automotive industry, aviation, aerospace, machine tools, instruments and household appliances. In this paper, taking a complex lithium battery box as an example, the integrated manufacturing of sheet metal parts is studied, and the digital integrated design and manufacturing process system is proposed. The technology is studied such as sheet metal design, unfolding, sheet nesting and laser cutting, CNC turret punch stamping programming, CNC bending etc. The feasibility of the method is verified through the examples of products and the integrated manufacturing of sheet metal box is completed.

Enhanced ice sheet melting driven by volcanic eruptions during the last deglaciation.

Science.gov (United States)

Muschitiello, Francesco; Pausata, Francesco S R; Lea, James M; Mair, Douglas W F; Wohlfarth, Barbara

2017-10-24

Volcanic eruptions can impact the mass balance of ice sheets through changes in climate and the radiative properties of the ice. Yet, empirical evidence highlighting the sensitivity of ancient ice sheets to volcanism is scarce. Here we present an exceptionally well-dated annual glacial varve chronology recording the melting history of the Fennoscandian Ice Sheet at the end of the last deglaciation (∼13,200-12,000 years ago). Our data indicate that abrupt ice melting events coincide with volcanogenic aerosol emissions recorded in Greenland ice cores. We suggest that enhanced ice sheet runoff is primarily associated with albedo effects due to deposition of ash sourced from high-latitude volcanic eruptions. Climate and snowpack mass-balance simulations show evidence for enhanced ice sheet runoff under volcanically forced conditions despite atmospheric cooling. The sensitivity of past ice sheets to volcanic ashfall highlights the need for an accurate coupling between atmosphere and ice sheet components in climate models.

24 CFR 1710.117 - Cost sheet, signature of Senior Executive Officer.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Cost sheet, signature of Senior... REGISTRATION Reporting Requirements § 1710.117 Cost sheet, signature of Senior Executive Officer. (a) Cost... description of our subdivision and development plans. Signature of Senior Executive Officer (2) Cost sheet...

Preparation of multilayer graphene sheets and their applications for particle accelerators

Science.gov (United States)

Tatami, Atsushi; Tachibana, Masamitsu; Yagi, Takashi; Murakami, Mutsuaki

2018-05-01

Multilayer graphene sheets were prepared by heat treatment of polyimide films at temperatures of up to 3000 °C. The sheets consist of highly oriented graphite layers with excellent mechanical robustness and flexibility. Key features of these sheets include their high thermal conductivity in the in-plane direction, good mechanical properties, and high carbon purity. The results suggest that the multilayer graphene sheets have great potential for charge stripping foils that persist even under the highest ion beam intensities irradiation and can be used for accelerator applications.

Investigation of Forming Performance of Laminated Steel Sheets Using Finite Element Analyses

International Nuclear Information System (INIS)

Liu Wenning; Sun Xin; Ruokolainen, Robert; Gayden Xiaohong

2007-01-01

Laminated steel sheets have been used in automotive structures for reducing in-cabin noise. However, due to the marked difference in material properties of the different laminated layers, integrating laminated steel parts into the manufacturing processes can be challenging. Especially, the behavior of laminated sheets during forming processes is very different from that of monolithic steel sheets. During the deep-draw forming process, large shear deformation and corresponding high interfacial stress may initiate and propagate interfacial cracks between the core polymer and the metal skin, hence degrading the performance of the laminated sheets. In this paper, the formability of the laminated steel sheets is investigated by means of numerical analysis. The goal of this work is to gain insight into the relationship between the individual properties of the laminated sheet layers and the corresponding formability of the laminated sheet as a whole, eventually leading to reliable design and successful forming process development of such materials. Finite element analyses of laminate sheet forming are presented. Effects of polymer core thickness and viscoelastic properties of the polymer core, as well as punching velocity, are also investigated

Moisture content in raw rubber sheet analyzed by transflectance near infrared spectroscopy

Directory of Open Access Journals (Sweden)

Ronnarit Rittiron

2014-07-01

Full Text Available Moisture content is an important trait for rubber sheet trading system. Therefore, a calibration equation for predicting moisture content was created by near infrared (NIR technique in order to develop a more fair trading system in Thailand. Spectra were recorded in two systems. One was measurement on each rubber sheet and the other was on a pile of sheets. Both were measured by a handheld NIR spectrometer in the short wavelength region (700–1100 nm in the transflectance mode using Teflon as a diffuse reflector. The spectra showed the peak at about 900 nm which belongs to isoprene, the major component of rubber sheet. Pretreatment with second derivative was applied to remove baseline shift effect occurring due to thickness differences on each rubber sheet. From validation results, moisture contents predicted by single sheet system were more accurate than a pile of sheet system with standard error of prediction (SEP = 0.39% and bias of -0.07%, and they were not significantly different from the actual values at 95% confidence. As a result, determining moisture content in each rubber sheet by a handheld NIR spectrometer provided accurate values, easy and rapid operation.

Quantifying stretching and rearrangement in epithelial sheet migration

International Nuclear Information System (INIS)

Lee, Rachel M; Nordstrom, Kerstin N; Losert, Wolfgang; Kelley, Douglas H; Ouellette, Nicholas T

2013-01-01

Although understanding the collective migration of cells, such as that seen in epithelial sheets, is essential for understanding diseases such as metastatic cancer, this motion is not yet as well characterized as individual cell migration. Here we adapt quantitative metrics used to characterize the flow and deformation of soft matter to contrast different types of motion within a migrating sheet of cells. Using a finite-time Lyapunov exponent (FTLE) analysis, we find that—in spite of large fluctuations—the flow field of an epithelial cell sheet is not chaotic. Stretching of a sheet of cells (i.e. positive FTLE) is localized at the leading edge of migration and increases when the cells are more highly stimulated. By decomposing the motion of the cells into affine and non-affine components using the metric D m in 2 , we quantify local plastic rearrangements and describe the motion of a group of cells in a novel way. We find an increase in plastic rearrangements with increasing cell densities, whereas inanimate systems tend to exhibit less non-affine rearrangements with increasing density. (paper)

Exploring teachers' perspectives on the impact of out-of-school science-based programs for secondary level physics classrooms in Nebraska

Science.gov (United States)

Baquerizo-Birth, Marisol

This exploratory phenomenological study investigates the lived experiences of six high school physics teachers in Nebraska regarding their perceptions on the impact of participating in a science-based out-of-school program. By exploring the research question, we discover how this experience relates to these teachers' self-concept and professional growth. Open-ended, semi-structured, one-on-one interviews are used as the data collection method to explore teachers' perceptions. Responses reveal that teachers participating in the Cosmic Ray Observatory Project (CROP) as a means of exploring advanced, extracurricular physics projects perceive their participation as an opportunity for enrichment, collaboration, helping their students, and empowerment. Intertwined in the presented narratives, teachers refer to their schools' limited administrative support as a source of struggle tied to the challenge of balancing school and teaching responsibilities with CROP participants' responsibilities. This study proposes teachers must feel confident with their specific subject area to achieve a progressive view of self, and that supplemental professional development opportunities are crucial to physics teaching.

SiC/C composite sheets produced from polycarbosilane/resin/bonder mixtures. Polycarbosilane/jushi/bonder kongokei kara sakuseishita SiC/C fukugo sheet

Energy Technology Data Exchange (ETDEWEB)

Kawamura, K. (The National Defense Academy, Kanagawa (Japan)); Koga, J.; Iwata, T.; Yamanaka, S.; Ono, M. (Mitsubishi Materials Corp., Saitama (Japan))

1992-02-01

In a course of work to improve anti-oxidative property and strength of sheets of carbonic composite materials with resins, and further to produce those sheets in an industrial scale, it was tried to prepare two types of 0.4 {approximately} 0.6 m thickness SiC / C composite sheets by heat treatment of two green sheets polycarbosilane ( PCS ) / fran resin / binder type and PCS / (phenol-formaldehyde resin / binder type ) at temperature of 1200 {approximately} 1400{degree}C in an atmosphere of nitrogen. The sheets thus made were subjected to SEM observation, X-ray diffraction, measurement of density and electric resistance, and to tests on weight loss by heating and on bending. The texture of them were as tight as that of their resin carbon ( glassy carbon ). The structural feature is formation of amorphous SiO{sub 2} as a secondary product, This indicates that Si in PCS reacts with oxygen in resin during pyrolysis. The bending strength and anti-oxidative property depend on the SiC content from PCS and that the mixing effect of SiC on them are feasible when a mixing ratio of PCS / resin is higher than (2/1). 13 ref., 7 figs., 2 tabs.

Multi-scale magnetic field intermittence in the plasma sheet

Directory of Open Access Journals (Sweden)

Z. Vörös

2003-09-01

Full Text Available This paper demonstrates that intermittent magnetic field fluctuations in the plasma sheet exhibit transitory, localized, and multi-scale features. We propose a multifractal-based algorithm, which quantifies intermittence on the basis of the statistical distribution of the "strength of burstiness", estimated within a sliding window. Interesting multi-scale phenomena observed by the Cluster spacecraft include large-scale motion of the current sheet and bursty bulk flow associated turbulence, interpreted as a cross-scale coupling (CSC process.Key words. Magnetospheric physics (magnetotail; plasma sheet – Space plasma physics (turbulence

Complete plasma dropouts at Vela satellites during thinning of the plasma sheet

International Nuclear Information System (INIS)

Lui, A.T.Y.; Hones, E.W. Jr.; Venkatesan, D.; Akasofu, S.; Bame, S.J.

1975-01-01

Five satellite years of Vela data are examined for plasma sheet thinnings. Complete proton disappearances (plasma dropouts) are the main subject here. During such times, the Vela satellite is temporarily in the high-latitude tail lobe. The distribution of such plasma dropouts within the magnetotail suggests that the semithickness of the plasma sheet near midnight seldom reaches less than 1 R/sub E/ during substorms and that the dawn and dusk portions of the plasma sheet remain thicker than the midnight portion. But it is also shown that the plasma sheet occasionally becomes very thin near the dusk magnetopause. No such severe thinnings of the plasma sheet are found near the dawn magnetopause. Plasma dropouts can occur regardless of the sign of the Z component of the IMF, but their frequency of occurrence seems to be greater when the Z component is negative.Three plasma dropouts which occurred in the midnight sector at unusually large distances from the estimated position of the neutral sheet were observed during geomagnetic storms. It is likely that the midnight sector of the plasma sheet can become very thick (approx.18 R/sub E/) at certain times during the main phase of storms. Detailed measurements in the plasma sheet were obtained near the beginning of a geomagnetic storm whose sc triggered a substorm. A compression of the plasma sheet at X/sub SM/approx. =-15 R/sub E/ occurred about 10 min after the sc onset at the earth and about 5 min after the start of plasma sheet thinning associated with the sc-related substorm. If compression-thinning of the plasma sheet initiated this substorm, the triggering action must have occurred earthward of X/sub SM/approx. =-15 R/sub E/

77 FR 32998 - Tin- and Chromium-Coated Steel Sheet From Japan

Science.gov (United States)

2012-06-04

...-Coated Steel Sheet From Japan Determination On the basis of the record \\1\\ developed in the subject five... order on tin- and chromium-coated steel sheet from Japan would be likely to lead to continuation or... USITC Publication 4325 (May 2012), entitled Tin- and Chromium-Coated Steel Sheet from Japan...

Precisely Assembled Nanofiber Arrays as a Platform to Engineer Aligned Cell Sheets for Biofabrication

Directory of Open Access Journals (Sweden)

Vince Beachley

2014-08-01

Full Text Available A hybrid cell sheet engineering approach was developed using ultra-thin nanofiber arrays to host the formation of composite nanofiber/cell sheets. It was found that confluent aligned cell sheets could grow on uniaxially-aligned and crisscrossed nanofiber arrays with extremely low fiber densities. The porosity of the nanofiber sheets was sufficient to allow aligned linear myotube formation from differentiated myoblasts on both sides of the nanofiber sheets, in spite of single-side cell seeding. The nanofiber content of the composite cell sheets is minimized to reduce the hindrance to cell migration, cell-cell contacts, mass transport, as well as the foreign body response or inflammatory response associated with the biomaterial. Even at extremely low densities, the nanofiber component significantly enhanced the stability and mechanical properties of the composite cell sheets. In addition, the aligned nanofiber arrays imparted excellent handling properties to the composite cell sheets, which allowed easy processing into more complex, thick 3D structures of higher hierarchy. Aligned nanofiber array-based composite cell sheet engineering combines several advantages of material-free cell sheet engineering and polymer scaffold-based cell sheet engineering; and it represents a new direction in aligned cell sheet engineering for a multitude of tissue engineering applications.

Recent development of non-oriented electrical steel sheet for automobile electrical devices

International Nuclear Information System (INIS)

Oda, Yoshihiko; Kohno, Masaaki; Honda, Atsuhito

2008-01-01

This paper describes non-oriented electrical steel sheet for automobile motors and reactors. Electrical steel sheets for energy efficient motors show high magnetic flux density and low iron loss. They are suitable for HEV traction motors and EPS motors. A thin-gauge electrical steel sheet and a gradient Si steel sheet show low iron loss in the high-frequency range. Therefore, the efficiency of high-frequency devices can be greatly improved. Since a 6.5% Si steel sheet possesses low iron loss and zero magnetostriction, it contributes to reduce the core loss and audible noise of high-frequency reactors

Easy synthesis of graphene sheets from alfalfa plants by treatment of nitric acid

International Nuclear Information System (INIS)

Qu, Jiao; Luo, Chunqiu; Zhang, Qian; Cong, Qiao; Yuan, Xing

2013-01-01

Highlights: ► An easy method for synthesis of graphene sheets using alfalfa plants was introduced. ► An novelty formation mechanism of graphene sheets using alfalfa plants was proposed. ► This method exploits a new carbon source and provides a novel idea to synthesize graphene sheets. -- Abstract: This letter focuses on synthesis of graphene sheets from alfalfa plants by treatment of nitric acid. The transmission electron microscopy image (TEM) demonstrates that the graphene sheets are agglomerated and overlapped, the energy dispersive spectrum (EDS) indicates that the products are pure, and the Raman spectrum shows the graphene sheets are well graphitized. In addition, the formation mechanism of the graphene sheets from alfalfa plants by treatment nitric acid is discussed. These findings inspire the search for a new strategy for synthesis of graphene sheets from renewable natural products, and the lower cost of this new process and carbon source may facilitate industrial production

Easy synthesis of graphene sheets from alfalfa plants by treatment of nitric acid

Energy Technology Data Exchange (ETDEWEB)

Qu, Jiao, E-mail: qujiao@bhu.edu.cn [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024 (China); Luo, Chunqiu, E-mail: fplj_lcq@163.com [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); Zhang, Qian; Cong, Qiao [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); Yuan, Xing [School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024 (China)

2013-04-01

Highlights: ► An easy method for synthesis of graphene sheets using alfalfa plants was introduced. ► An novelty formation mechanism of graphene sheets using alfalfa plants was proposed. ► This method exploits a new carbon source and provides a novel idea to synthesize graphene sheets. -- Abstract: This letter focuses on synthesis of graphene sheets from alfalfa plants by treatment of nitric acid. The transmission electron microscopy image (TEM) demonstrates that the graphene sheets are agglomerated and overlapped, the energy dispersive spectrum (EDS) indicates that the products are pure, and the Raman spectrum shows the graphene sheets are well graphitized. In addition, the formation mechanism of the graphene sheets from alfalfa plants by treatment nitric acid is discussed. These findings inspire the search for a new strategy for synthesis of graphene sheets from renewable natural products, and the lower cost of this new process and carbon source may facilitate industrial production.

Thin current sheets observation by MMS during a near-Earth's magnetotail reconnection event

Science.gov (United States)

Nakamura, R.; Varsani, A.; Nakamura, T.; Genestreti, K.; Plaschke, F.; Baumjohann, W.; Nagai, T.; Burch, J.; Cohen, I. J.; Ergun, R.; Fuselier, S. A.; Giles, B. L.; Le Contel, O.; Lindqvist, P. A.; Magnes, W.; Schwartz, S. J.; Strangeway, R. J.; Torbert, R. B.

2017-12-01

During summer 2017, the four spacecraft of the Magnetospheric Multiscale (MMS) mission traversed the nightside magnetotail current sheet at an apogee of 25 RE. They detected a number of flow reversal events suggestive of the passage of the reconnection current sheet. Due to the mission's unprecedented high-time resolution and spatial separation well below the ion scales, structure of thin current sheets is well resolved both with plasma and field measurements. In this study we examine the detailed structure of thin current sheets during a flow reversal event from tailward flow to Earthward flow, when MMS crossed the center of the current sheet . We investigate the changes in the structure of the thin current sheet relative to the X-point based on multi-point analysis. We determine the motion and strength of the current sheet from curlometer calculations comparing these with currents obtained from the particle data. The observed structures of these current sheets are also compared with simulations.

Improving Climate Literacy Using The Ice Sheet System Model (ISSM): A Prototype Virtual Ice Sheet Laboratory For Use In K-12 Classrooms

Science.gov (United States)

Halkides, D. J.; Larour, E. Y.; Perez, G.; Petrie, K.; Nguyen, L.

2013-12-01

Statistics indicate that most Americans learn what they will know about science within the confines of our public K-12 education system and the media. Next Generation Science Standards (NGSS) aim to remedy science illiteracy and provide guidelines to exceed the Common Core State Standards that most U.S. state governments have adopted, by integrating disciplinary cores with crosscutting ideas and real life practices. In this vein, we present a prototype ';Virtual Ice Sheet Laboratory' (I-Lab), geared to K-12 students, educators and interested members of the general public. I-Lab will allow users to perform experiments using a state-of-the-art dynamical ice sheet model and provide detailed downloadable lesson plans, which incorporate this model and are consistent with NGSS Physical Science criteria for different grade bands (K-2, 3-5, 6-8, and 9-12). The ultimate goal of this website is to improve public climate science literacy, especially in regards to the crucial role of the polar ice sheets in Earth's climate and sea level. The model used will be the Ice Sheet System Model (ISSM), an ice flow model developed at NASA's Jet Propulsion Laboratory and UC Irvine, that simulates the near-term evolution of polar ice sheets (Greenland and Antarctica) and includes high spatial resolution capabilities and data assimilation to produce realistic simulations of ice sheet dynamics at the continental scale. Open sourced since 2011, ISSM is used in cutting edge cryosphere research around the globe. Thru I-Lab, students will be able to access ISSM using a simple, online graphical interface that can be launched from a web browser on a computer, tablet or smart phone. The interface will allow users to select different climate conditions and watch how the polar ice sheets evolve in time under those conditions. Lesson contents will include links to background material and activities that teach observation recording, concept articulation, hypothesis formulation and testing, and

A Novel Method of Modeling the Deformation Resistance for Clad Sheet

International Nuclear Information System (INIS)

Hu Jianliang; Yi Youping; Xie Mantang

2011-01-01

Because of the excellent thermal conductivity, the clad sheet (3003/4004/3003) of aluminum alloy is extensively used in various heat exchangers, such as radiator, motorcar air conditioning, evaporator, and so on. The deformation resistance model plays an important role in designing the process parameters of hot continuous rolling. However, the complex behaviors of the plastic deformation of the clad sheet make the modeling very difficult. In this work, a novel method for modeling the deformation resistance of clad sheet was proposed by combining the finite element analysis with experiments. The deformation resistance model of aluminum 3003 and 4004 was proposed through hot compression test on the Gleeble-1500 thermo-simulation machine. And the deformation resistance model of clad sheet was proposed through finite element analysis using DEFORM-2D software. The relationship between cladding ratio and the deformation resistance was discussed in detail. The results of hot compression simulation demonstrate that the cladding ratio has great effects on the resistance of the clad sheet. Taking the cladding ratio into consideration, the mathematical model of the deformation resistance for clad sheet has been proved to have perfect forecasting precision of different cladding ratio. Therefore, the presented model can be used to predict the rolling force of clad sheet during the hot continuous rolling process.

Substorms in the Inner Plasma Sheet

Science.gov (United States)

Le Contel, O.; Perraut, S.; Roux, A.; Pellat, R.; Korth, A.

Thin Current Sheets (TCS) are regularly formed prior to substorm breakup, even in the near-Earth plasma sheet, as close as the geostationary orbit. A self-consistent kinetic theory describing the response of the plasma sheet to an electromagnetic perturbation is given. This perturbation corresponds to an external forcing, for instance caused by the solar wind (not an internal instability). The equilibrium of the configuration of this TCS in the presence of a time varying perturbation is shown to produce a strong parallel thermal anisotropy (T∥ > T⊺) of energetic electrons and ions (E>50keV) as well as an enhanced diamagnetic current carried by low energy ions (Ecurrents tend to enhance the confinement of this current sheet near the magnetic equator. These results are compared with data gathered by GEOS-2 at the geostationary orbit, where the magnetic signatures of TCS, and parallel anisotropies are regularly observed prior to breakup. By ensuring quasi-neutrality everywhere we find, when low frequency electromagnetic perturbations are applied, that although the magnetic field line remains an equipotential to the lowest order in Te/Ti, a field-aligned potential drop exists to the next order in (Te/Ti). Thus the development of a TCS implies the formation of a field-aligned potential drop (~= few hundred volts) to ensure the quasi-neutrality everywhere. For an earthward directed pressure gradient, a field-aligned electric field, directed towards the ionosphere, is obtained, on the western edge of the perturbation (i.e. western edge of the current sheet). Thus field aligned beams of electrons are expected to flow towards the equatorial region on the western edge of the current sheet. We study the stability of these electron beams and show that they are unstable to ``High Frequency'' (HF) waves. These ``HF'' waves are regularly observed at frequencies of the order of the proton gyrofrequency (fH+) just before, or at breakup. The amplitude of these HF waves is so

Groundwater flow modelling under ice sheet conditions. Scoping calculations

International Nuclear Information System (INIS)

Jaquet, O.; Namar, R.; Jansson, P.

2010-10-01

The potential impact of long-term climate changes has to be evaluated with respect to repository performance and safety. In particular, glacial periods of advancing and retreating ice sheet and prolonged permafrost conditions are likely to occur over the repository site. The growth and decay of ice sheets and the associated distribution of permafrost will affect the groundwater flow field and its composition. As large changes may take place, the understanding of groundwater flow patterns in connection to glaciations is an important issue for the geological disposal at long term. During a glacial period, the performance of the repository could be weakened by some of the following conditions and associated processes: - Maximum pressure at repository depth (canister failure). - Maximum permafrost depth (canister failure, buffer function). - Concentration of groundwater oxygen (canister corrosion). - Groundwater salinity (buffer stability). - Glacially induced earthquakes (canister failure). Therefore, the GAP project aims at understanding key hydrogeological issues as well as answering specific questions: - Regional groundwater flow system under ice sheet conditions. - Flow and infiltration conditions at the ice sheet bed. - Penetration depth of glacial meltwater into the bedrock. - Water chemical composition at repository depth in presence of glacial effects. - Role of the taliks, located in front of the ice sheet, likely to act as potential discharge zones of deep groundwater flow. - Influence of permafrost distribution on the groundwater flow system in relation to build-up and thawing periods. - Consequences of glacially induced earthquakes on the groundwater flow system. Some answers will be provided by the field data and investigations; the integration of the information and the dynamic characterisation of the key processes will be obtained using numerical modelling. Since most of the data are not yet available, some scoping calculations are performed using the

Groundwater flow modelling under ice sheet conditions. Scoping calculations

Energy Technology Data Exchange (ETDEWEB)

Jaquet, O.; Namar, R. (In2Earth Modelling Ltd (Switzerland)); Jansson, P. (Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden))

2010-10-15

The potential impact of long-term climate changes has to be evaluated with respect to repository performance and safety. In particular, glacial periods of advancing and retreating ice sheet and prolonged permafrost conditions are likely to occur over the repository site. The growth and decay of ice sheets and the associated distribution of permafrost will affect the groundwater flow field and its composition. As large changes may take place, the understanding of groundwater flow patterns in connection to glaciations is an important issue for the geological disposal at long term. During a glacial period, the performance of the repository could be weakened by some of the following conditions and associated processes: - Maximum pressure at repository depth (canister failure). - Maximum permafrost depth (canister failure, buffer function). - Concentration of groundwater oxygen (canister corrosion). - Groundwater salinity (buffer stability). - Glacially induced earthquakes (canister failure). Therefore, the GAP project aims at understanding key hydrogeological issues as well as answering specific questions: - Regional groundwater flow system under ice sheet conditions. - Flow and infiltration conditions at the ice sheet bed. - Penetration depth of glacial meltwater into the bedrock. - Water chemical composition at repository depth in presence of glacial effects. - Role of the taliks, located in front of the ice sheet, likely to act as potential discharge zones of deep groundwater flow. - Influence of permafrost distribution on the groundwater flow system in relation to build-up and thawing periods. - Consequences of glacially induced earthquakes on the groundwater flow system. Some answers will be provided by the field data and investigations; the integration of the information and the dynamic characterisation of the key processes will be obtained using numerical modelling. Since most of the data are not yet available, some scoping calculations are performed using the

New type of nonglossy image-receiving sheet

Science.gov (United States)

Aono, Toshiaki; Shibata, Takeshi; Nakamura, Yoshisada

1990-07-01

We have developed a new type of non-glossy surface of an image receiving sheet for a photothermographic color hardcopy system. There is a basic conflict in realizing uniform dye transfer with use of a receiving sheet having a matted surface, because when the degree of roughness exceeds a certain extent, uneven dye transfer readily takes place. It: has been solved by use of "microscopic" phase separation of a certain water-soluble polymer blend which constitutes the surface layer of the image receiving sheet. One of the preferable polymer blends for our purpose proved to be a ternary system, consisting of sodium salt of polymethacrylic acid (PMAA-Na), ammonium salt of polyacrylic acid (PAA-NH4) and water. Phase separation, which proceeded during the evaporation of water from the coated mixture, turned out to be of a spinodal decomposition type and thus capable of stably providing a desirable non-glossy surface.

Zinc oxide nanorod clusters deposited seaweed cellulose sheet for antimicrobial activity.

Science.gov (United States)

Bhutiya, Priyank L; Mahajan, Mayur S; Abdul Rasheed, M; Pandey, Manoj; Zaheer Hasan, S; Misra, Nirendra

2018-06-01

Seaweed cellulose was isolated from green seaweed Ulva fasciata using a common bleaching agent. Sheet containing porous mesh was prepared from the extracted seaweed crystalline cellulose along with zinc oxide (ZnO) nanorod clusters grown over the sheet by single step hydrothermal method. Seaweed cellulose and zinc oxide nanorod clusters deposited seaweed cellulose sheet was characterized by FT-IR, XRD, TGA, and SEM-EDX. Morphology showed that the diameter of zinc oxide nanorods were around 70nm. Zinc oxide nanorod clusters deposited on seaweed cellulose sheet gave remarkable antibacterial activity towards gram-positive (Staphylococcus aureus, Bacillus ceresus, Streptococcus thermophilis) and gram-negative (Escherichia coli, Pseudomonas aeruginous) microbes. Such deposited sheet has potential applications in pharmaceutical, biomedical, food packaging, water treatment and biotechnological industries. Copyright © 2018 Elsevier B.V. All rights reserved.

Clouds enhance Greenland ice sheet mass loss

Science.gov (United States)

Van Tricht, Kristof; Gorodetskaya, Irina V.; L'Ecuyer, Tristan; Lenaerts, Jan T. M.; Lhermitte, Stef; Noel, Brice; Turner, David D.; van den Broeke, Michiel R.; van Lipzig, Nicole P. M.

2015-04-01

Clouds have a profound influence on both the Arctic and global climate, while they still represent one of the key uncertainties in climate models, limiting the fidelity of future climate projections. The potentially important role of thin liquid-containing clouds over Greenland in enhancing ice sheet melt has recently gained interest, yet current research is spatially and temporally limited, focusing on particular events, and their large scale impact on the surface mass balance remains unknown. We used a combination of satellite remote sensing (CloudSat - CALIPSO), ground-based observations and climate model (RACMO) data to show that liquid-containing clouds warm the Greenland ice sheet 94% of the time. High surface reflectivity (albedo) for shortwave radiation reduces the cloud shortwave cooling effect on the absorbed fluxes, while not influencing the absorption of longwave radiation. Cloud warming over the ice sheet therefore dominates year-round. Only when albedo values drop below ~0.6 in the coastal areas during summer, the cooling effect starts to overcome the warming effect. The year-round excess of energy due to the presence of liquid-containing clouds has an extensive influence on the mass balance of the ice sheet. Simulations using the SNOWPACK snow model showed not only a strong influence of these liquid-containing clouds on melt increase, but also on the increased sublimation mass loss. Simulations with the Community Earth System Climate Model for the end of the 21st century (2080-2099) show that Greenland clouds contain more liquid water path and less ice water path. This implies that cloud radiative forcing will be further enhanced in the future. Our results therefore urge the need for improving cloud microphysics in climate models, to improve future projections of ice sheet mass balance and global sea level rise.

Up-scalable sheet-to-sheet production of high efficiency perovskite module and solar cells on 6-in. substrate using slot die coating

NARCIS (Netherlands)

Di Giacomo, Francesco; Shanmugam, Santhosh; Fledderus, Henri; Bruijnaers, Bardo J.; Verhees, Wiljan J.H.; Dorenkamper, Maarten S.; Veenstra, Sjoerd C.; Qiu, Weiming; Gehlhaar, Robert; Merckx, Tamara; Aernouts, Tom; Andriessen, Ronn; Galagan, Yulia

2018-01-01

Scalable sheet-to-sheet slot die coating processes have been demonstrated for perovskite solar cells and modules. The processes have been developed on 6 in. × 6 in. glass/ITO substrates for two functional layers: the perovskite photo-active layer and the Spiro-OMeTAD hole transport layer. Perovskite

Ocean Tide Influences on the Antarctic and Greenland Ice Sheets

Science.gov (United States)

Padman, Laurie; Siegfried, Matthew R.; Fricker, Helen A.

2018-03-01

Ocean tides are the main source of high-frequency variability in the vertical and horizontal motion of ice sheets near their marine margins. Floating ice shelves, which occupy about three quarters of the perimeter of Antarctica and the termini of four outlet glaciers in northern Greenland, rise and fall in synchrony with the ocean tide. Lateral motion of floating and grounded portions of ice sheets near their marine margins can also include a tidal component. These tide-induced signals provide insight into the processes by which the oceans can affect ice sheet mass balance and dynamics. In this review, we summarize in situ and satellite-based measurements of the tidal response of ice shelves and grounded ice, and spatial variability of ocean tide heights and currents around the ice sheets. We review sensitivity of tide heights and currents as ocean geometry responds to variations in sea level, ice shelf thickness, and ice sheet mass and extent. We then describe coupled ice-ocean models and analytical glacier models that quantify the effect of ocean tides on lower-frequency ice sheet mass loss and motion. We suggest new observations and model developments to improve the representation of tides in coupled models that are used to predict future ice sheet mass loss and the associated contribution to sea level change. The most critical need is for new data to improve maps of bathymetry, ice shelf draft, spatial variability of the drag coefficient at the ice-ocean interface, and higher-resolution models with improved representation of tidal energy sinks.

Stiffness Matrices and Anisotropy in the Trapezoidal Corrugated Composite Sheets

Directory of Open Access Journals (Sweden)

Mohammad Golzar

2013-10-01

Full Text Available In the some applications like as morphing technology, high strain and anisotropic behavior are essential design requirements. The corrugated composite sheets due to their special geometries have potential to high deflection under axial loading through longitudinal direction of corrugation. In this research, the strain and the anisotropic behavior of corrugated composite sheets are investigated by fabricating glass/epoxy samples with trapezoidal geometries. For evaluation of the mechanical behavior of the composites the samples were subjected to tension and flexural tests in the longitudinal and transverse directions of corrugation. In order to determine anisotropic behavior of the corrugated sheets, two approaches were introduced: (1 tensile anisotropic (E* and (2 flexural anisotropic (D*. The anisotropic behavior and ultimate deflections were investigated theoretically and experimentally. In this paper, mechanical behaviors based on theoretical and experimental analysis including the elastic constants and stiffness matrices of trapezoidal corrugated composite sheets were studied and the results were verified by finite element method. The results of the numerical and analytical solutions were compared with those of experimental tests. Finally, the load-displacement curves of tensile tests in longitudinal direction of corrugation, the ultimate deflection and anisotropy behavior of these exclusive composite sheets in the corrugated composite sheets were studied experimentally. The experimental results of the trapezoidal corrugated sheets showed that one of the most important parameters in the ultimate strain was amplitude of the corrugation elements. Generally, increasing the amplitude and element per length unit of trapezoidal corrugated specimen led to higher ultimate strain.

THE USE OF EDUCATIONAL MODELS OF DNA IN CLASSROOM BY TEACHERS OF ELEMENTARY SCHOOL

Directory of Open Access Journals (Sweden)

F.M. Chiari

2007-05-01

Full Text Available The importance of the teaching of Biotechnology and Molecular Biology is evidenced by the progress of those areas and it generates a demand in the updating of science and biology teachers. In that sense, a project was proposed inside of the Public Education Program of FAPESP, in partnership with CBME.The goal was evaluate, among other educational tools, the contribution of the plastic models "Building the molecules of the life: DNA and RNA" in the teaching and learning of these concepts. Nine science teachers of public elementary schools had an updating course after which they elaborated a diagnosis questionnaire in order to subsidize the application of the activities in the classroom. The activities were planned seeking contextualize the subject in classroom, taking into account the difficulties detected in the diagnosis questionnaire. A sheet of notes was elaborated, where the teachers could record their observations and thoughts after the application of the activities, as well as their possibilities and the students' difficulties. These registers indicated that the teachers were satisfied with the use of the material, which made possible a deepened study on the content and a greater interest and participation of the students. It also allowed a reflection on their practice, glimpsing new ways to teach.

Method of manufacturing aluminide sheet by thermomechanical processing of aluminide powders

Science.gov (United States)

Hajaligol, Mohammad R.; Scorey, Clive; Sikka, Vinod K.; Deevi, Seetharama C.; Fleischhauer, Grier; Lilly, Jr., A. Clifton; German, Randall M.

2000-01-01

A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr.ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3% Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

The Svalbard-Barents Sea ice-sheet - Historical, current and future perspectives

Science.gov (United States)

Ingólfsson, Ólafur; Landvik, Jon Y.

2013-03-01

The history of research on the Late Quaternary Svalbard-Barents Sea ice sheet mirrors the developments of ideas and the shifts of paradigms in glacial theory over the past 150 years. Since the onset of scientific research there in the early 19th Century, Svalbard has been a natural laboratory where ideas and concepts have been tested, and played an important (but rarely acknowledged) role in the break-through of the Ice Age theory in the 1870's. The history of how the scientific perception of the Svalbard-Barents sea ice sheet developed in the mid-20th Century also tells a story of how a combination of fairly scattered and often contradictory observational data, and through both deductive and inductive reasoning, could outline a major ice sheet that had left but few tangible fingerprints. Since the 1980's, with increased terrestrial stratigraphical data, ever more marine geological evidence and better chronological control of glacial events, our perception of the Svalbard-Barents Sea ice sheet has changed. The first reconstructions depicted it as a static, concentric, single-domed ice sheet, with ice flowing from an ice divide over the central northern Barents Sea that expanded and declined in response to large-scale, Late Quaternary climate fluctuations, and which was more or less in tune with other major Northern Hemisphere ice sheets. We now increasingly perceive it as a very dynamic, multidomed ice sheet, controlled by climate fluctuations, relative sea-level change, as well as subglacial topography, substrate properties and basal temperature. In this respect, the Svalbard-Barents Sea ice sheet will increasingly hold the key for understanding the dynamics and processes of how marine-based ice sheets build-up and decay.

Teachers and Technology Use in Secondary Science Classrooms: Investigating the Experiences of Middle School Science Teachers Implementing the Web-based Inquiry Science Environment (WISE)

Science.gov (United States)

Schulz, Rachel Corinne

This study investigated the intended teacher use of a technology-enhanced learning tool, Web-based Inquiry Science Environment (WISE), and the first experiences of teachers new to using it and untrained in its use. The purpose of the study was to learn more about the factors embedded into the design of the technology that enabled it or hindered it from being used as intended. The qualitative research design applied grounded theory methods. Using theoretical sampling and a constant comparative analysis, a document review of WISE website led to a model of intended teacher use. The experiences of four middle school science teachers as they enacted WISE for the first time were investigated through ethnographic field observations, surveys and interviews using thematic analysis to construct narratives of each teachers use. These narratives were compared to the model of intended teacher use of WISE. This study found two levels of intended teacher uses for WISE. A basic intended use involved having student running the project to completion while the teacher provides feedback and assesses student learning. A more optimal description of intended use involved the supplementing the core curriculum with WISE as well as enhancing the core scope and sequence of instruction and aligning assessment with the goals of instruction through WISE. Moreover, WISE projects were optimally intended to be facilitated through student-centered teaching practices and inquiry-based instruction in a collaborative learning environment. It is also optimally intended for these projects to be shared with other colleagues for feedback and iterative development towards improving the Knowledge Integration of students. Of the four teachers who participated in this study, only one demonstrated the use of WISE as intended in the most basic way. This teacher also demonstrated the use of WISE in a number of optimal ways. Teacher confusion with certain tools available within WISE suggests that there may be a

Blending Online Components into Traditional Instruction in Pre-Service Teacher Education: The Good, the Bad, and the Ugly

Science.gov (United States)

Lin, Hong

2008-01-01

This study investigated the effectiveness of using online instruction as a supplement to a face-to-face introductory technology education course. Survey data were collected from 46 pre-service teachers. Findings indicated that when traditional face-to-face instruction was combined with online components, learning was enhanced over a single…

A flexible tactile sensitive sheet using a hetero-core fiber optic sensor

Science.gov (United States)

Fujino, S.; Yamazaki, H.; Hosoki, A.; Watanabe, K.

2014-05-01

In this report, we have designed a tactile sensitive sheet based on a hetero-core fiber-optic sensor, which realize an areal sensing by using single sensor potion in one optical fiber line. Recently, flexible and wide-area tactile sensing technology is expected to applied to acquired biological information in living space and robot achieve long-term care services such as welfare and nursing-care and humanoid technology. A hetero-core fiber-optic sensor has several advantages such as thin and flexible transmission line, immunity to EMI. Additionally this sensor is sensitive to moderate bending actions with optical loss changes and is independent of temperature fluctuation. Thus, the hetero-core fiber-optic sensor can be suitable for areal tactile sensing. We measure pressure characteristic of the proposed sensitive sheet by changing the pressure position and pinching characteristic on the surface. The proposed tactile sensitive sheet shows monotonic responses on the whole sensitive sheet surface although different sensitivity by the position is observed at the sensitive sheet surface. Moreover, the tactile sensitive sheet could sufficiently detect the pinching motion. In addition, in order to realize the discrimination between pressure and pinch, we fabricated a doubled-over sensor using a set of tactile sensitive sheets, which has different kinds of silicon robbers as a sensitive sheet surface. In conclusion, the flexible material could be given to the tactile sensation which is attached under proposed sensitive sheet.

Experimental analysis of Nd-YAG laser cutting of sheet materials - A review

Science.gov (United States)

Sharma, Amit; Yadava, Vinod

2018-01-01

Cutting of sheet material is considered as an important process due to its relevance among products of everyday life such as aircrafts, ships, cars, furniture etc. Among various sheet cutting processes (ASCPs), laser beam cutting is one of the most capable ASCP to create complex geometries with stringent design requirements in difficult-to-cut sheet materials. Based on the recent research work in the area of sheet cutting, it is found that the Nd-YAG laser is used for cutting of sheet material in general and reflective sheet material in particular. This paper reviews the experimental analysis of Nd-YAG laser cutting process, carried out to study the influence of laser cutting parameters on the process performance index. The significance of experimental modeling and different optimization approaches employed by various researchers has also been discussed in this study.

MHD Ballooning Instability in the Plasma Sheet

International Nuclear Information System (INIS)

Cheng, C.Z.; Zaharia, S.

2003-01-01

Based on the ideal-MHD model the stability of ballooning modes is investigated by employing realistic 3D magnetospheric equilibria, in particular for the substorm growth phase. Previous MHD ballooning stability calculations making use of approximations on the plasma compressibility can give rise to erroneous conclusions. Our results show that without making approximations on the plasma compressibility the MHD ballooning modes are unstable for the entire plasma sheet where beta (sub)eq is greater than or equal to 1, and the most unstable modes are located in the strong cross-tail current sheet region in the near-Earth plasma sheet, which maps to the initial brightening location of the breakup arc in the ionosphere. However, the MHD beq threshold is too low in comparison with observations by AMPTE/CCE at X = -(8 - 9)R(sub)E, which show that a low-frequency instability is excited only when beq increases over 50. The difficulty is mitigated by considering the kinetic effects of ion gyrorad ii and trapped electron dynamics, which can greatly increase the stabilizing effects of field line tension and thus enhance the beta(sub)eq threshold [Cheng and Lui, 1998]. The consequence is to reduce the equatorial region of the unstable ballooning modes to the strong cross-tail current sheet region where the free energy associated with the plasma pressure gradient and magnetic field curvature is maximum

Modeling sheet-flow sand transport under progressive surface waves

NARCIS (Netherlands)

Kranenburg, Wouter

2013-01-01

In the near-shore zone, energetic sea waves generate sheet-flow sand transport. In present day coastal models, wave-induced sheet-flow sand transport rates are usually predicted with semi-empirical transport formulas, based on extensive research on this phenomenon in oscillatory flow tunnels.

Uncertainty Quantification for Large-Scale Ice Sheet Modeling

Energy Technology Data Exchange (ETDEWEB)

Ghattas, Omar [Univ. of Texas, Austin, TX (United States)

2016-02-05

This report summarizes our work to develop advanced forward and inverse solvers and uncertainty quantification capabilities for a nonlinear 3D full Stokes continental-scale ice sheet flow model. The components include: (1) forward solver: a new state-of-the-art parallel adaptive scalable high-order-accurate mass-conservative Newton-based 3D nonlinear full Stokes ice sheet flow simulator; (2) inverse solver: a new adjoint-based inexact Newton method for solution of deterministic inverse problems governed by the above 3D nonlinear full Stokes ice flow model; and (3) uncertainty quantification: a novel Hessian-based Bayesian method for quantifying uncertainties in the inverse ice sheet flow solution and propagating them forward into predictions of quantities of interest such as ice mass flux to the ocean.

Efficient tunable luminescence of SiGe alloy sheet polymers

International Nuclear Information System (INIS)

Vogg, G.; Meyer, A. J.-P.; Miesner, C.; Brandt, M. S.; Stutzmann, M.

2001-01-01

Crystalline SiGe alloy sheet polymers were topotactically prepared from epitaxially grown calcium germanosilicide Ca(Si 1-x Ge x ) 2 precursor films in the whole composition range. These polygermanosilynes are found to be a well-defined mixture of the known siloxene and polygermyne sheet polymers with the OH groups exclusively bonded to silicon. The optical properties determined by photoluminescence and optical reflection measurements identify the mixed SiGe sheet polymers as direct semiconductors with efficient luminescence tunable in the energy range between 2.4 and 1.3 eV. [copyright] 2001 American Institute of Physics

Equivalence Between Squirrel Cage and Sheet Rotor Induction Motor

Science.gov (United States)

Dwivedi, Ankita; Singh, S. K.; Srivastava, R. K.

2016-06-01

Due to topological changes in dual stator induction motor and high cost of its fabrication, it is convenient to replace the squirrel cage rotor with a composite sheet rotor. For an experimental machine, the inner and outer stator stampings are normally available whereas the procurement of rotor stampings is quite cumbersome and is not always cost effective. In this paper, the equivalence between sheet/solid rotor induction motor and squirrel cage induction motor has been investigated using layer theory of electrical machines, so as to enable one to utilize sheet/solid rotor in dual port experimental machines.

Elastic Buckling Behaviour of General Multi-Layered Graphene Sheets

Directory of Open Access Journals (Sweden)

Rong Ming Lin

2015-04-01

Full Text Available Elastic buckling behaviour of multi-layered graphene sheets is rigorously investigated. Van der Waals forces are modelled, to a first order approximation, as linear physical springs which connect the nodes between the layers. Critical buckling loads and their associated modes are established and analyzed under different boundary conditions, aspect ratios and compressive loading ratios in the case of graphene sheets compressed in two perpendicular directions. Various practically possible loading configurations are examined and their effect on buckling characteristics is assessed. To model more accurately the buckling behaviour of multi-layered graphene sheets, a physically more representative and realistic mixed boundary support concept is proposed and applied. For the fundamental buckling mode under mixed boundary support, the layers with different boundary supports deform similarly but non-identically, leading to resultant van der Waals bonding forces between the layers which in turn affect critical buckling load. Results are compared with existing known solutions to illustrate the excellent numerical accuracy of the proposed modelling approach. The buckling characteristics of graphene sheets presented in this paper form a comprehensive and wholesome study which can be used as potential structural design guideline when graphene sheets are employed for nano-scale sensing and actuation applications such as nano-electro-mechanical systems.

Ice shelf fracture parameterization in an ice sheet model

Science.gov (United States)

Sun, Sainan; Cornford, Stephen L.; Moore, John C.; Gladstone, Rupert; Zhao, Liyun

2017-11-01

Floating ice shelves exert a stabilizing force onto the inland ice sheet. However, this buttressing effect is diminished by the fracture process, which on large scales effectively softens the ice, accelerating its flow, increasing calving, and potentially leading to ice shelf breakup. We add a continuum damage model (CDM) to the BISICLES ice sheet model, which is intended to model the localized opening of crevasses under stress, the transport of those crevasses through the ice sheet, and the coupling between crevasse depth and the ice flow field and to carry out idealized numerical experiments examining the broad impact on large-scale ice sheet and shelf dynamics. In each case we see a complex pattern of damage evolve over time, with an eventual loss of buttressing approximately equivalent to halving the thickness of the ice shelf. We find that it is possible to achieve a similar ice flow pattern using a simple rule of thumb: introducing an enhancement factor ˜ 10 everywhere in the model domain. However, spatially varying damage (or equivalently, enhancement factor) fields set at the start of prognostic calculations to match velocity observations, as is widely done in ice sheet simulations, ought to evolve in time, or grounding line retreat can be slowed by an order of magnitude.

47 CFR 32.3000 - Instructions for balance sheet accounts-Depreciation and amortization.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Instructions for balance sheet accounts-Depreciation and amortization. 32.3000 Section 32.3000 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... for Balance Sheet Accounts § 32.3000 Instructions for balance sheet accounts—Depreciation and...

Active components in food supplements

NARCIS (Netherlands)

Siemelink M; Jansen EHJM; Piersma AH; Opperhuizen A; LEO

2000-01-01

The growing food supplement market, where supplements are both more diverse and more easily available (e.g. through Internet) formed the backdrop to the inventory of the active components in food supplements. The safety of an increased intake of food components via supplements was also at issue

State Fact Sheets on COPD

Science.gov (United States)

... Submit Search The CDC Chronic Obstructive Pulmonary Disease (COPD) Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . COPD Homepage Data and Statistics Fact Sheets Publications Publications ...

A test sheet generating algorithm based on intelligent genetic algorithm and hierarchical planning

Science.gov (United States)

Gu, Peipei; Niu, Zhendong; Chen, Xuting; Chen, Wei

2013-03-01

In recent years, computer-based testing has become an effective method to evaluate students' overall learning progress so that appropriate guiding strategies can be recommended. Research has been done to develop intelligent test assembling systems which can automatically generate test sheets based on given parameters of test items. A good multisubject test sheet depends on not only the quality of the test items but also the construction of the sheet. Effective and efficient construction of test sheets according to multiple subjects and criteria is a challenging problem. In this paper, a multi-subject test sheet generation problem is formulated and a test sheet generating approach based on intelligent genetic algorithm and hierarchical planning (GAHP) is proposed to tackle this problem. The proposed approach utilizes hierarchical planning to simplify the multi-subject testing problem and adopts genetic algorithm to process the layered criteria, enabling the construction of good test sheets according to multiple test item requirements. Experiments are conducted and the results show that the proposed approach is capable of effectively generating multi-subject test sheets that meet specified requirements and achieve good performance.

Microprobe metrology for direct sheet resistance and mobility characterization

DEFF Research Database (Denmark)

Nielsen, Peter Folmer; Petersen, Dirch Hjorth; Lin, Rong

2012-01-01

The M4PP measurement technique has gained increased interest from the semiconductor industry for direct sheet resistance measurements on ultra thin layers and small structures/pads. Several fully automatic microRSP probing tools are today in use for in-line sheet resistance measurements on blanket...

Modeling of AlMg Sheet Forming at Elevated Temperatures

NARCIS (Netherlands)

van den Boogaard, Antonius H.; Bolt, P.; Werkhoven, R.

2001-01-01

The process limits of aluminum sheet forming processes can be improved by control-ling local flow behavior by means of elevated temperatures and temperature gradients. In order to accurately model the deep drawing or stretching of aluminum sheet at elevated temperatures, a model is required that

Dynamics of fluid lines, sheets, filaments and membranes

International Nuclear Information System (INIS)

Coutris, N.

1988-01-01

We establish the dynamic equations of two types of fluid structures: 1) lines-filaments and 2) sheets-membranes. In the first part, we consider one-dimensional (line) and two-dimensional (sheet) fluid structures. The second part concerns the associated three- dimensional structures: filaments and membranes. In the third part, we establish the equations for thickened lines and thickened sheets. For that purpose, we introduce a thickness in the models of the first part. The fourth part concerns the thinning of the filament and the membrane. Then, by an asymptotic process, we deduce the corresponding equations from the equations of the second part in order to show the purely formal equivalence of the equations of the third and fourth parts. To obtain the equations, we make use of theorems whose proofs can be found in the appendices. The equations can be applied to many areas of interest: instabilities of liquid jets and liquid films, modelisation of interfaces between two different fluids as sheets or membranes, modelisation with the averaged equations over a cross section of single phase flows and two-phase flows in channels with a nonrectilinear axis such as bends or pump casings [fr

Creutzfeldt-Jakob Disease Fact Sheet for Healthcare Workers and Morticians

Science.gov (United States)

... here Home » Disorders » Patient & Caregiver Education » Fact Sheets Creutzfeldt-Jakob Disease Fact Sheet for Healthcare Workers and Morticians Creutzfeldt-Jakob disease (CJD) is a rare, fatal brain disorder that ...

Collision of hydrogen molecules interacting with two grapheme sheets

Directory of Open Access Journals (Sweden)

Malivuk-Gak Dragana

2017-01-01

Full Text Available It have been performed the computational experiments with two hydrogen molecules and two graphene sheets. Hydrogen - hydrogen and hydrogen - carbon interactions are described by Lennard - Jones potential. Equations of motion of the wave packet centre are solved numerically. The initial molecule velocity was determined by temperature and collisions occur in central point between two sheets. The molecules after collision stay near or get far away of graphene sheets. Then one can find what temperatures, graphene sheet sizes and their distances are favourable for hydrogen storage. It is found that quantum corrections of the molecule classical trajectories are not significant here. Those investigations of possibility of hydrogen storage by physisorption are of interest for improvement of the fuel cell systems. The main disadvantages of computational experiments are: (1 it cannot compute with very large number of C atoms, (2 it is assumed that carbon atoms are placed always in their equilibrium positions and (3 the changes of wave packet width are not considered.

Investigation of the Formability of TRIP780 Steel Sheets

Science.gov (United States)

Song, Yang

The formability of a metal sheet is dependent on its work hardening behaviour and its forming limits; and both aspects must be carefully determined in order to accurately simulate a particular forming process. This research aims to characterize the formability of a TRIP780 sheet steel using advanced experimental testing and analysis techniques. A series of flat rolling and tensile tests, as well as shear tests were conducted to determine the large deformation work hardening behaviour of this TRIP780 steel. Nakazima tests were carried out up to fracture to determine the forming limits of this sheet material. A highly-automated method for generating a robust FLC for sheet materials from DIC strain measurements was created with the help of finite element simulations, and evaluated against the conventional method. A correction algorithm that aims to compensate for the process dependent effects in the Nakazima test was implemented and tested with some success.

40 CFR 427.20 - Applicability; description of the asbestos-cement sheet subcategory.

Science.gov (United States)

2010-07-01

... asbestos-cement sheet subcategory. 427.20 Section 427.20 Protection of Environment ENVIRONMENTAL PROTECTION... Asbestos-Cement Sheet Subcategory § 427.20 Applicability; description of the asbestos-cement sheet... asbestos, Portland cement, silica, and other ingredients are used in the manufacturing of asbestos-cement...

MICROBIOLOGICAL QUALITY OF FOOD SUPPLEMENTS.

Science.gov (United States)

Ratajczak, Magdalena; Kubicka, Marcelina M; Kamińska, Dorota; Długaszewska, Jolanta

2015-01-01

Many specialists note that the food offered today - as a result of very complex technological processing - is devoid of many components that are important for the organism and the shortages have to be supplemented. The simplest for it is to consume diet supplements that provide the missing element in a concentrated form. In accordance with the applicable law, medicinal products include all substances or mixtures of substances that are attributed with properties of preventing or treating diseases with humans or animals. Permits to admit supplements to the market are issued by the Chief Sanitary Inspector and the related authorities; permits for medicines are issued by the Chief Pharmaceutical Inspector and the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products. Therefore, admittance of a supplement to the market is less costly and time consuming_than admittance of a medicine. Supplements and medicines may contain the same component but medicines will have a larger concentration than supplements. Sale of supplements at drug stores and in the form of tablets, capsules, liquids or powders makes consumer often confusing supplements with medicines. Now there are no normative documents specifying limits of microbiological impurities in diet supplements. In Polish legislation, diet supplements are subject to legal acts concerning food. Medicines have to comply with microbiological purity requirements specified in the Polish Pharmacopeia. As evidenced with the completed tests, the proportion of diet supplement samples with microbiological impurities is 6.5%. Sales of diet supplements have been growing each year, they are consumed by healthy people but also people with immunology deficiencies and by children and therefore consumers must be certain that they buy safe products.

Flapping dynamics of a thin liquid sheet

Science.gov (United States)

Vadivukkarasan, M.; Kumaran, Dhivyaraja; Panchagnula, Mahesh; Multi-phase flow physics Group Team

2017-11-01

We attempt to delineate and describe the complete evolution of a thin soap film when air is blown through a nozzle in the normal direction. The sequence of events and its intrinsic dynamics are captured using high speed imaging. By careful observation, it was observed that multiple mechanisms occur in the same system and each event is triggered by an independent mechanism. The events include (a) flapping of a liquid sheet and pinching of the bubble, (b) onset of rupture on the liquid sheet, (c) formation of ligaments and (d) ejection of drops. From this study, it is shown that these events are predominantly governed by Kelvin-Helmholtz instability, Taylor - Culick law, Rayleigh-Taylor instability and capillary instability, respectively. The present experiments can be considered as an extension to the previous studies on soap films as well as thin flapping sheets which has direct relevance to coaxial atomizers used in aircraft applications.

Mass balance of the Antarctic ice sheet.

Science.gov (United States)

Wingham, D J; Shepherd, A; Muir, A; Marshall, G J

2006-07-15

The Antarctic contribution to sea-level rise has long been uncertain. While regional variability in ice dynamics has been revealed, a picture of mass changes throughout the continental ice sheet is lacking. Here, we use satellite radar altimetry to measure the elevation change of 72% of the grounded ice sheet during the period 1992-2003. Depending on the density of the snow giving rise to the observed elevation fluctuations, the ice sheet mass trend falls in the range -5-+85Gtyr-1. We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend-growth of 27+/-29Gtyr-1-is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise.

Involving Practicing Scientists in K-12 Science Teacher Professional Development

Science.gov (United States)

Bertram, K. B.

2011-12-01

The Science Teacher Education Program (STEP) offered a unique framework for creating professional development courses focused on Arctic research from 2006-2009. Under the STEP framework, science, technology, engineering, and math (STEM) training was delivered by teams of practicing Arctic researchers in partnership with master teachers with 20+ years experience teaching STEM content in K-12 classrooms. Courses based on the framework were offered to educators across Alaska. STEP offered in-person summer-intensive institutes and follow-on audio-conferenced field-test courses during the academic year, supplemented by online scientist mentorship for teachers. During STEP courses, teams of scientists offered in-depth STEM content instruction at the graduate level for teachers of all grade levels. STEP graduate-level training culminated in the translation of information and data learned from Arctic scientists into standard-aligned lessons designed for immediate use in K-12 classrooms. This presentation will focus on research that explored the question: To what degree was scientist involvement beneficial to teacher training and to what degree was STEP scientist involvement beneficial to scientist instructors? Data sources reveal consistently high levels of ongoing (4 year) scientist and teacher participation; high STEM content learning outcomes for teachers; high STEM content learning outcomes for students; high ratings of STEP courses by scientists and teachers; and a discussion of the reasons scientists indicate they benefited from STEP involvement. Analyses of open-ended comments by teachers and scientists support and clarify these findings. A grounded theory approach was used to analyze teacher and scientist qualitative feedback. Comments were coded and patterns analyzed in three databases. The vast majority of teacher open-ended comments indicate that STEP involvement improved K-12 STEM classroom instruction, and the vast majority of scientist open-ended comments

Off-Balance Sheet Financing.

Science.gov (United States)

Adams, Matthew C.

1998-01-01

Examines off-balance sheet financing, the facilities use of outsourcing for selected needs, as a means of saving operational costs and using facility assets efficiently. Examples of using outside sources for energy supply and food services, as well as partnering with business for facility expansion are provided. Concluding comments address tax…

W-Band Sheet Beam Klystron Design

International Nuclear Information System (INIS)

Scheitrum, G.; Caryotakis, G.; Burke, A.; Jensen, A.; Jongewaard, E.; Krasnykh, A.; Neubauer, M.; Phillips, R.; Rauenbuehler, K.

2011-01-01

Sheet beam devices provide important advantages for very high power, narrow bandwidth RF sources like accelerator klystrons (1). Reduced current density and increased surface area result in increased power capabi1ity, reduced magnetic fields for focusing and reduced cathode loading. These advantages are offset by increased complexity, beam formation and transport issues and potential for mode competition in the ovennoded cavities and drift tube. This paper will describe the design issues encountered in developing a 100 kW peak and 2 kW average power sheet beam k1ystron at W-band including beam formation, beam transport, circuit design, circuit fabrication and mode competition.

Taking iron supplements

Science.gov (United States)

... medlineplus.gov/ency/article/007478.htm Taking iron supplements To use the sharing features on this page, ... levels. You may also need to take iron supplements as well to rebuild iron stores in your ...

Comparative properties of ceramic-based roofing sheets from local ...

African Journals Online (AJOL)

Ceramic roofing sheets were fabricated in the laboratory by using ideal raw materials. The fabricating materials are coiled coconut fibre, palm fruit fibre, fresh water, river sand, polymeric dust, saw dust and cement. The resulting product was compared with factory -produced ceramic-based roofing sheets that are easily ...

Interactions between ice sheets, climate and the solid Earth

NARCIS (Netherlands)

Berg, J. van den

2007-01-01

The melting of ice sheets in response to increasing temperatures is an important contribution to present day sea level rise. To predict the amount of sea level rise and to assess its impact on populated coastal regions, an increased understanding of the physical processes governing ice sheets is

A Teacher-Focused Intervention to Decrease PE Students' Amotivation by Increasing Need Satisfaction and Decreasing Need Frustration.

Science.gov (United States)

Cheon, Sung Hyeon; Reeve, Johnmarshall; Song, Yong-Gwan

2016-06-01

Intervention-induced gains in need satisfaction decrease PE students' amotivation. The present study adopted a dual-process model to test whether an intervention could also decrease need frustration and hence provide a second supplemental source to further decrease students' PE amotivation. Using an experimental, longitudinal research design, 19 experienced PE teachers (9 experimental, 10 control) and their 1,017 students participated in an intervention program to help teachers become both more autonomy supportive and less controlling. Multilevel repeated measures analyses showed that students of teachers in the experimental group reported greater T2, T3, and T4 perceived autonomy support, need satisfaction, and engagement and lesser T2, T3, and T4 perceived teacher control, need frustration, and amotivation than did students of teachers in the control group. Multilevel structural equation modeling analyses confirmed the hypothesized dual-process model in which both intervention-induced increases in need satisfaction and intervention-induced decreases need frustration decreased students' end-of-semester amotivation. We discuss the theoretical and practical implications of this new finding on the dual antecedents of diminished amotivation.

Controlling microstructure and texture in magnesium alloy sheet by shear-based deformation processing

Science.gov (United States)

Sagapuram, Dinakar

Application of lightweight Mg sheet is limited by its low workability, both in production of sheet (typically by multistep hot and cold-rolling) and forming of sheet into components. Large strain extrusion machining (LSEM), a constrained chip formation process, is used to create Mg alloy AZ31B sheet in a single deformation step. The deformation in LSEM is shown to be intense simple shear that is confined to a narrow zone, which results in significant deformation-induced heating up to ~ 200°C and reduces the need for pre-heating to realize continuous sheet forms. This study focuses on the texture and microstructure development in the sheet processed by LSEM. Interestingly, deep, highly twinned steady-state layer develops in the workpiece subsurface due to the compressive field ahead of the shear zone. The shear deformation, in conjunction with this pre-deformed twinned layer, results in tilted-basal textures in the sheet with basal planes tilted well away from the surface. These textures are significantly different from those in rolled sheet, where basal planes are nearly parallel to the surface. By controlling the strain path, the basal plane inclination from the surface could be varied in the range of 32-53°. B-fiber (basal plane parallel to LSEM shear plane), associated with basal slip, is the major texture component in the sheet. An additional minor C2-fiber component appears above 250°C due to the thermal activation of pyramidal slip. Together with these textures, microstructure ranges from severely cold-worked to (dynamically) recrystallized type, with the corresponding grain sizes varying from ultrafine- (~ 200 nm) to fine- (2 mum) grained. Small-scale limiting dome height (LDH) confirmed enhanced formability (~ 50% increase in LDH) of LSEM sheet over the conventional rolled sheet. Premature, twinning-driven shear fractures are observed in the rolled sheet with the basal texture. In contrast, LSEM sheet with a tilted-basal texture favorably oriented for

ICESat's First Year of Measurements Over the Polar Ice Sheets

Science.gov (United States)

Shuman, C. A.

2004-05-01

NASA's Ice, Cloud and Land Elevation Satellite (ICESat) mission was developed to measure changes in elevation of the Greenland and Antarctic ice sheets. Its primary mission goal is to significantly refine estimates of polar ice sheet mass balance. Obtaining precise, spatially dense, ice sheet elevations through time is the first step towards this goal. ICESat data will then enable study of associations between observed ice changes and dynamic or climatic forcing factors, and thus enable improved estimation of the present and future contributions of the ice sheets to global sea level rise. ICESat was launched on January 12, 2003 and acquired science data from February 20th to March 29th with the first of the three lasers of the Geoscience Laser Altimeter System (GLAS). Data acquisition with the second laser began on September 25th and continued until November 18th, 2003. For one-year change detection, the second laser is scheduled for operation from approximately February 17th to March 20th, 2004. Additional operational periods will be selected to 1) enable periodic measurements through the year, and 2) to support of other NASA Earth Science Enterprise missions and activities. To obtain these precise ice sheet elevations, GLAS has a 1064 nm wavelength laser operating at 40 Hz with a designed range precision of about 10 cm. The laser footprints are about 70 m in diameter on the Earth's surface and are spaced every 172 m along-track. The on-board GPS receiver enables radial orbit determinations to an accuracy better than 5 cm. The star-tracking attitude-determination system will enable laser footprints to be located to 6 m horizontally when attitude calibration is completed. The orbital altitude averages 600 km at an inclination of 94 degrees with coverage extending from 86 degrees N and S latitude. The spacecraft attitude can be controlled to point the laser beam to within 50 m of surface reference tracks over the ice sheets and to point off-nadir up to 5 degrees to

The Interaction of C-Band Microwaves with Large Plasma Sheets

International Nuclear Information System (INIS)

Ding Liang; Huo Wenqing; Yang Xinjie; Xu Yuemin

2012-01-01

A large plasma sheet 60 cm×60 cm×2 cm in size was generated using a hollow cathode, and measurements were conducted for interactions including transmission, reflection and absorption. With different discharge parameters, plasma sheets can vary and influence microwave strength. Microwave reflection decreases when the discharge current rises, and the opposite occurs in transmission. The C-band microwave is absorbed when it is propagated through large plasma sheets at higher pressure. When plasma density and collision frequency are fitted with incident microwave frequency, a large amount of microwave energy is consumed. Reflection, transmission and absorption all exist simultaneously. Plasma sheets are an attractive alternative to microwave steering at low pressure, and the microwave reflection used in receiving radar can be altered by changing the discharge parameters.

Vibrational analysis of single-layered graphene sheets

Energy Technology Data Exchange (ETDEWEB)

Sakhaee-Pour, A; Ahmadian, M T [Center of Excellence in Design, Robotics and Automation (CEDRA), Department of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Naghdabadi, R [Department of Mechanical Engineering and Institute for Nano Science and Technology, Sharif University of Technology, Tehran (Iran, Islamic Republic of)], E-mail: sakhaee@alum.sharif.edu, E-mail: naghdabd@sharif.edu

2008-02-27

A molecular structural mechanics method has been implemented to investigate the vibrational behavior of single-layered graphene sheets. By adopting this approach, mode shapes and natural frequencies are obtained. Vibrational analysis is performed with different chirality and boundary conditions. Numerical results from the atomistic modeling are employed to develop predictive equations via a statistical nonlinear regression model. With the proposed equations, fundamental frequencies of single-layered graphene sheets with considered boundary conditions can be predicted within 3% difference with respect to the atomistic simulation.

Initial rigid response and softening transition of highly stretchable kirigami sheet materials.

Science.gov (United States)

Isobe, Midori; Okumura, Ko

2016-04-27

We study, experimentally and theoretically, the mechanical response of sheet materials on which line cracks or cuts are arranged in a simple pattern. Such sheet materials, often called kirigami (the Japanese words, kiri and gami, stand for cut and paper, respectively), demonstrate a unique mechanical response promising for various engineering applications such as stretchable batteries: kirigami sheets possess a mechanical regime in which sheets are highly stretchable and very soft compared with the original sheets without line cracks, by virtue of out-of-plane deformation. However, this regime starts after a transition from an initial stiff regime governed by in-plane deformation. In other words, the softness of the kirigami structure emerges as a result of a transition from the two-dimensional to three-dimensional deformation, i.e., from stretching to bending. We clarify the physical origins of the transition and mechanical regimes, which are revealed to be governed by simple scaling laws. The results could be useful for controlling and designing the mechanical response of sheet materials including cell sheets for medical regeneration and relevant to the development of materials with tunable stiffness and mechanical force sensors.

Finnish Cooperating Physics Teachers' Conceptions of Physics Teachers' Teacher Knowledge

Science.gov (United States)

Asikainen, Mervi A.; Hirvonen, Pekka E.

2010-01-01

This article examines Finnish cooperating physics teachers' conceptions of teacher knowledge in physics. Six experienced teachers were interviewed. The data was analyzed to form categories concerning the basis of teacher knowledge, and the tradition of German Didaktik and Shulman's theory of teacher knowledge were used in order to understand the…

Large-scale Modeling of the Greenland Ice Sheet on Long Timescales

DEFF Research Database (Denmark)

Solgaard, Anne Munck

is investigated as well as its early history. The studies are performed using an ice-sheet model in combination with relevant forcing from observed and modeled climate. Changes in ice-sheet geometry influences atmospheric flow (and vice versa) hereby changing the forcing patterns. Changes in the overall climate...... and climate model is included shows, however, that a Föhn effect is activated and hereby increasing temperatures inland and inhibiting further ice-sheet expansion into the interior. This indicates that colder than present temperatures are needed in order for the ice sheet to regrow to the current geometry....... Accordingto this hypothesis, two stages of uplift since the Late Miocene lead to the present-day topography. The results of the ice-sheet simulations show geometries in line with geologicobservations through the period, and it is found that the uplift events enhance the effect of the climatic deterioration...

Methodologies for analysis of patterning in the mouse RPE sheet

Science.gov (United States)

Boatright, Jeffrey H.; Dalal, Nupur; Chrenek, Micah A.; Gardner, Christopher; Ziesel, Alison; Jiang, Yi; Grossniklaus, Hans E.

2015-01-01

Purpose Our goal was to optimize procedures for assessing shapes, sizes, and other quantitative metrics of retinal pigment epithelium (RPE) cells and contact- and noncontact-mediated cell-to-cell interactions across a large series of flatmount RPE images. Methods The two principal methodological advances of this study were optimization of a mouse RPE flatmount preparation and refinement of open-access software to rapidly analyze large numbers of flatmount images. Mouse eyes were harvested, and extra-orbital fat and muscles were removed. Eyes were fixed for 10 min, and dissected by puncturing the cornea with a sharp needle or a stab knife. Four radial cuts were made with iridectomy scissors from the puncture to near the optic nerve head. The lens, iris, and the neural retina were removed, leaving the RPE sheet exposed. The dissection and outcomes were monitored and evaluated by video recording. The RPE sheet was imaged under fluorescence confocal microscopy after staining for ZO-1 to identify RPE cell boundaries. Photoshop, Java, Perl, and Matlab scripts, as well as CellProfiler, were used to quantify selected parameters. Data were exported into Excel spreadsheets for further analysis. Results A simplified dissection procedure afforded a consistent source of images that could be processed by computer. The dissection and flatmounting techniques were illustrated in a video recording. Almost all of the sheet could be routinely imaged, and substantial fractions of the RPE sheet (usually 20–50% of the sheet) could be analyzed. Several common technical problems were noted and workarounds developed. The software-based analysis merged 25 to 36 images into one and adjusted settings to record an image suitable for large-scale identification of cell-to-cell boundaries, and then obtained quantitative descriptors of the shape of each cell, its neighbors, and interactions beyond direct cell–cell contact in the sheet. To validate the software, human- and computer

Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning.

Science.gov (United States)

Krabill; Abdalati; Frederick; Manizade; Martin; Sonntag; Swift; Thomas; Wright; Yungel

2000-07-21

Aircraft laser-altimeter surveys over northern Greenland in 1994 and 1999 have been coupled with previously reported data from southern Greenland to analyze the recent mass-balance of the Greenland Ice Sheet. Above 2000 meters elevation, the ice sheet is in balance on average but has some regions of local thickening or thinning. Thinning predominates at lower elevations, with rates exceeding 1 meter per year close to the coast. Interpolation of our results between flight lines indicates a net loss of about 51 cubic kilometers of ice per year from the entire ice sheet, sufficient to raise sea level by 0.13 millimeter per year-approximately 7% of the observed rise.

Indoor external dose rates due to decorative sheet stone

Energy Technology Data Exchange (ETDEWEB)

Lu, C.H.; Sheu, R.D.; Jiang, S.H. [Dept. of Engineering and System Science, National Tsing Hua Univ., Hsinchu (Taiwan)

2002-03-01

The specific activities in decorative sheet stone made of granite or marble were measured, whereby the absolute peak efficiency of the HPGe detectors employed in the measurements for the sheet-stone sample was determined using the semi-empirical method. The spatial distribution for the indoor external dose rates due to the radionuclides present in the decorative sheet stone used to clad the floor and the four walls of a standard room was calculated using a three-dimensional point kernel computer code. It was found that the spatial distribution for the indoor dose rates was complex and non-uniform, which represents a difference in relation to the results of earlier studies. (orig.)

Indoor external dose rates due to decorative sheet stone

International Nuclear Information System (INIS)

Lu, C.H.; Sheu, R.D.; Jiang, S.H.

2002-01-01

The specific activities in decorative sheet stone made of granite or marble were measured, whereby the absolute peak efficiency of the HPGe detectors employed in the measurements for the sheet-stone sample was determined using the semi-empirical method. The spatial distribution for the indoor external dose rates due to the radionuclides present in the decorative sheet stone used to clad the floor and the four walls of a standard room was calculated using a three-dimensional point kernel computer code. It was found that the spatial distribution for the indoor dose rates was complex and non-uniform, which represents a difference in relation to the results of earlier studies. (orig.)

Substructure and electrical resistivity analyses of pure tungsten sheet

International Nuclear Information System (INIS)

Trybus, C.L.; Sellers, C.H.; Anderl, R.A.

1991-01-01

The substructure of pure tungsten sheet (0.025 mm thick) is examined and quantified by transmission electron microscopy (TEM). Dislocation populations and arrangements are evaluated for as-worked and various annealed conditions of the tungsten sheet. The worked (rolled) tungsten substructure was nonhomogeneous, consisting of areas of very high and low dislocation densities. These results are correlated to resistivity measurements of the tungsten sheet following thermal cycling to 1200 degrees C to determine the substructural changes as a function of temperature. The comparison between the two characterization techniques is used to examine the relationship between structural and electronic properties in tungsten. 15 refs., 6 figs., 2 tabs

Ethanol Basics (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2015-01-01

Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

电子乐谱综述%The Summary of Electronic Sheet Music

Institute of Scientific and Technical Information of China (English)

许锦生; 林嘉宇; 周巍

2012-01-01

随着科学技术的发展,电子乐谱在人们学习乐器中扮演的角色越来越重要.通过对电子乐谱发展历程的了解,分析各种电子乐谱的优点及不足,提出了电子乐谱可以实现的四大功能,即:显示功能、播放功能、学习功能、乐谱库管理功能.%Following the development of science, Electronic Sheet Music is playing a more and more important position in playing a musical instrument. In this paper,we introduce the development of Electronic Sheet Music,and raise an issue by composite issues that people worked before, which Electronic Sheet Music could achieve four function. There are showwing Sheet Music, playing Sheet Music, Self -study function and Electronic Sheet Music management.

10 CFR 609.8 - Term sheets and conditional commitments.

Science.gov (United States)

2010-01-01

... Project Sponsor and the Eligible Lender or other Holder express agreement with the terms and conditions... 10 Energy 4 2010-01-01 2010-01-01 false Term sheets and conditional commitments. 609.8 Section 609... EMPLOY INNOVATIVE TECHNOLOGIES § 609.8 Term sheets and conditional commitments. (a) DOE, after review and...

Issues in Nutrition: Dietary Supplements.

Science.gov (United States)

Thompson, Margaret E; Noel, Mary Barth

2017-01-01

The majority of American adults report use of one or more dietary supplements every day or occasionally. The Dietary Supplement Health and Education Act of 1994 defines dietary supplements and regulates their manufacture and distribution. One of the most commonly used supplements is vitamin D. Measurement of serum levels of vitamin D must be undertaken with the caveats that different laboratories define normal levels differently, and that there is rarely a clinical correlation with the actual level. Patients should understand that supplements should not be used to excess, as there are toxicities and other adverse effects associated with most of them. There currently is considerable research being performed on probiotics and how the gut microbiome affects health and disease states. Protein supplements may be useful in reducing mortality rates in elderly patients but they do not appear to increase quality of life. If used, protein supplements should contain essential amino acids. Casein and whey supplements, derived from dairy sources, help transport essential amino acids to tissues. Although there have been many studies investigating the role of vitamin supplements in disease prevention, there have been few conclusive positive results. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

Lead in calcium supplements (abstract)

International Nuclear Information System (INIS)

Rehman, S.; Khalid, N.

2011-01-01

Lead present in calcium supplements is of grave concern as some lead levels have been measured up to the extent of regulatory limit set by the United States. Calcium supplements inevitably get contaminated with lead as both are naturally occurring elements. Therefore, it is imperative to indicate its level in these supplements in order to create awareness among consumers. In this study, a sophisticated analytical technique, atomic absorption spectrometry was used to analyze Pb contents in 27 commonly consumed Ca supplements manufactured by different national and multinational companies. The daily intake of lead through these supplements was calculated. Only 10% of the calcium supplements analyzed met the criteria of acceptable Pb levels (1.5 mu g/daily dose) in supplements/consumer products set by the United States. It was also found that Pb intake was highest in chelated calcium supplements 28.5 mu g/daily dose, whereas lowest 0.47 mu g/daily dose through calcium supplements with vitamin D formulation. In order to validate our results from the study conducted, IAEA-certified reference material (animal bone, H-5) was analyzed for its Pb levels. The levels of Pb determined were quite in good agreement with the certified values. (author)

Physician-Patient Communication about Dietary Supplements

Science.gov (United States)

Tarn, Derjung M.; Paterniti, Debora A.; Good, Jeffrey S.; Coulter, Ian D.; Galliher, James M.; Kravitz, Richard L.; Karlamangla, Arun; Wenger, Neil S.

2013-01-01

Objective Describe the content and frequency of provider-patient dietary supplement discussions during primary care office visits. Methods Inductive content analysis of 1477 transcribed audio-recorded office visits to 102 primary care providers was combined with patient and provider surveys. Encounters were collected in Los Angeles, California (2009–2010), geographically-diverse practice settings across the United States (2004–2005), and Sacramento, CA (1998–1999). Results Providers discussed 738 dietary supplements during encounters with 357 patients (24.2% of all encounters in the data). They mentioned: 1) reason for taking the supplement for 46.5% of dietary supplements; 2) how to take the supplement for 28.2%; 3) potential risks for 17.3%; 4) supplement effectiveness for 16.7%; and 5) supplement cost or affordability for 4.2%. Of these five topics, a mean of 1.13 (SD=1.2) topics were discussed for each supplement. More topics were reviewed for non-vitamin non-mineral supplements (mean 1.47 (SD=1.2)) than for vitamin/mineral supplements (mean 0.99 (SD=1.1); psupplements are occurring, it is clear that more discussion might be needed to inform patient decisions about supplement use. Practice Implication Physicians could more frequently address topics that may influence patient dietary supplement use, such as the risks, effectiveness, and costs of supplements. PMID:23466249

Thermal properties of highly structured composite and aluminium sheets in an aerodynamic tunnel

Science.gov (United States)

Kulhavy, Petr; Egert, Josef

This article deals with the thermodynamic behaviour of heat shields - structured metal and composite plates. Experiments have been carried out in a wind tunnel with an additional heating, which simulates the heat source from engine or exhaust pipe and simultaneously the airflow generated during a car movement. The tested sheets with hexagonal structure were a standard commercial made of aluminium and a second manufactured by replication (lamination, diffusion) from glass fabric. The airflow in a parallel way along the sheets was analysed experimentally in order to determine the heat transfer efficiency between surfaces of sheets and surrounding airflow. The temperature on the sheets was chosen to observe the effects of different sheets material, various heat power and airflow velocity. During the experiment a thermal input below the sheets and airflow velocity through the tunnel have been changed. The thermal field distribution on the metal sheet is different than in case of composite sheet. For the composite material the thermal field distribution was more homogeneous. This article describe briefly also methods of obtaining real composite geometry based on scanned data and their reconstruction for using in some future numerical models.

Thermal properties of highly structured composite and aluminium sheets in an aerodynamic tunnel

Directory of Open Access Journals (Sweden)

Kulhavy Petr

2017-01-01

Full Text Available This article deals with the thermodynamic behaviour of heat shields - structured metal and composite plates. Experiments have been carried out in a wind tunnel with an additional heating, which simulates the heat source from engine or exhaust pipe and simultaneously the airflow generated during a car movement. The tested sheets with hexagonal structure were a standard commercial made of aluminium and a second manufactured by replication (lamination, diffusion from glass fabric. The airflow in a parallel way along the sheets was analysed experimentally in order to determine the heat transfer efficiency between surfaces of sheets and surrounding airflow. The temperature on the sheets was chosen to observe the effects of different sheets material, various heat power and airflow velocity. During the experiment a thermal input below the sheets and airflow velocity through the tunnel have been changed. The thermal field distribution on the metal sheet is different than in case of composite sheet. For the composite material the thermal field distribution was more homogeneous. This article describe briefly also methods of obtaining real composite geometry based on scanned data and their reconstruction for using in some future numerical models.

A Modified Porous Titanium Sheet Prepared by Plasma-Activated Sintering for Biomedical Applications

Directory of Open Access Journals (Sweden)

Yukimichi Tamaki

2010-01-01

Full Text Available This study aimed to develop a contamination-free porous titanium scaffold by a plasma-activated sintering within an originally developed TiN-coated graphite mold. The surface of porous titanium sheet with or without a coated graphite mold was characterized. The cell adhesion property of porous titanium sheet was also evaluated in this study. The peak of TiC was detected on the titanium sheet processed with the graphite mold without a TiN coating. Since the titanium fiber elements were directly in contact with the carbon graphite mold during processing, surface contamination was unavoidable event in this condition. The TiC peak was not detectable on the titanium sheet processed within the TiN-coated carbon graphite mold. This modified plasma-activated sintering with the TiN-coated graphite mold would be useful to fabricate a contamination-free titanium sheet. The number of adherent cells on the modified titanium sheet was greater than that of the bare titanium plate. Stress fiber formation and the extension of the cells were observed on the titanium sheets. This modified titanium sheet is expected to be a new tissue engineering material in orthopedic bone repair.

Off-balance sheet exposures and banking crises in OECD countries

OpenAIRE

Barrell, R; Davis, P; Liadze, I; Karim, D

2012-01-01

Against the background of the acknowledged importance of off-balance-sheet exposures in the sub prime crisis, we seek to investigate whether this was a new phenomenon or common to earlier crises. Using a logit approach to predicting banking crises in 14 OECD countries we find a significant impact of a proxy for the ratio of banks‟ off-balance-sheet activity to total (off and on balance sheet) activity, as well as capital and liquidity ratios, the current account balance and GDP growth. These ...

Spread-sheet application to classify radioactive material for shipment

International Nuclear Information System (INIS)

Brown, A.N.

1998-01-01

A spread-sheet application has been developed at the Idaho National Engineering and Environmental Laboratory to aid the shipper when classifying nuclide mixtures of normal form, radioactive materials. The results generated by this spread-sheet are used to confirm the proper US DOT classification when offering radioactive material packages for transport. The user must input to the spread-sheet the mass of the material being classified, the physical form (liquid or not) and the activity of each regulated nuclide. The spread-sheet uses these inputs to calculate two general values: 1)the specific activity of the material and a summation calculation of the nuclide content. The specific activity is used to determine if the material exceeds the DOT minimal threshold for a radioactive material. If the material is calculated to be radioactive, the specific activity is also used to determine if the material meets the activity requirement for one of the three low specific activity designations (LSA-I, LSA-II, LSA-III, or not LSA). Again, if the material is calculated to be radioactive, the summation calculation is then used to determine which activity category the material will meet (Limited Quantity, Type A, Type B, or Highway Route Controlled Quantity). This spread-sheet has proven to be an invaluable aid for shippers of radioactive materials at the Idaho National Engineering and Environmental Laboratory. (authors)

Orientation determination of interfacial beta-sheet structures in situ.

Science.gov (United States)

Nguyen, Khoi Tan; King, John Thomas; Chen, Zhan

2010-07-01

Structural information such as orientations of interfacial proteins and peptides is important for understanding properties and functions of such biological molecules, which play crucial roles in biological applications and processes such as antimicrobial selectivity, membrane protein activity, biocompatibility, and biosensing performance. The alpha-helical and beta-sheet structures are the most widely encountered secondary structures in peptides and proteins. In this paper, for the first time, a method to quantify the orientation of the interfacial beta-sheet structure using a combined attenuated total reflectance Fourier transformation infrared spectroscopic (ATR-FTIR) and sum frequency generation (SFG) vibrational spectroscopic study was developed. As an illustration of the methodology, the orientation of tachyplesin I, a 17 amino acid peptide with an antiparallel beta-sheet, adsorbed to polymer surfaces as well as associated with a lipid bilayer was determined using the regular and chiral SFG spectra, together with polarized ATR-FTIR amide I signals. Both the tilt angle (theta) and the twist angle (psi) of the beta-sheet at interfaces are determined. The developed method in this paper can be used to obtain in situ structural information of beta-sheet components in complex molecules. The combination of this method and the existing methodology that is currently used to investigate alpha-helical structures will greatly broaden the application of optical spectroscopy in physical chemistry, biochemistry, biophysics, and structural biology.

Ice shelf fracture parameterization in an ice sheet model

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S. Sun

2017-11-01

Full Text Available Floating ice shelves exert a stabilizing force onto the inland ice sheet. However, this buttressing effect is diminished by the fracture process, which on large scales effectively softens the ice, accelerating its flow, increasing calving, and potentially leading to ice shelf breakup. We add a continuum damage model (CDM to the BISICLES ice sheet model, which is intended to model the localized opening of crevasses under stress, the transport of those crevasses through the ice sheet, and the coupling between crevasse depth and the ice flow field and to carry out idealized numerical experiments examining the broad impact on large-scale ice sheet and shelf dynamics. In each case we see a complex pattern of damage evolve over time, with an eventual loss of buttressing approximately equivalent to halving the thickness of the ice shelf. We find that it is possible to achieve a similar ice flow pattern using a simple rule of thumb: introducing an enhancement factor ∼ 10 everywhere in the model domain. However, spatially varying damage (or equivalently, enhancement factor fields set at the start of prognostic calculations to match velocity observations, as is widely done in ice sheet simulations, ought to evolve in time, or grounding line retreat can be slowed by an order of magnitude.

Forming properties and springback evaluation of copper beryllium sheets

International Nuclear Information System (INIS)

Tseng, A.A.; Jen, K.P.; Chen, T.C.; Kondetimmamhalli, R.

1995-01-01

Copper beryllium (CuBe) alloys possess excellent strength and conductivity. They have become the most important materials used for producing high reliability connectors and interconnections for electrical and electronic applications. As demand for high connection density in electrical and electronic products grows, springback behaviors become increasingly critical in fabricating these miniaturized contact components from sheet base materials. In the present article, a study of the springback behavior of CuBe sheets under different heat treatments is presented, with the goal of providing reliable information needed for fabricating more intricate connection parts. Both experimental and analytical techniques were adopted. The tensile tester was first used to study the springback related tensile properties. The governing tensile parameters on springback were identified, and their variations for sheets with different heat treatments were studied. It was found that a bilinear constitutive relationship can be characterize the stress strain behavior of the CuBe alloy. A closed form solution based on this bilinear relationship was formulated to predict the springback for the CuBe sheets at bending conditions. A V-shaped bend tester having an interchangeable punch to accommodate multiple radii was designed and built to evaluate the springback properties of CuBe sheets. A good correlation was found between the analytical predictions and experimental data. A parametric study, as an example, was also performed to provide the springback information needed for designing complicated connectors

Liquid Film Migration in Warm Formed Aluminum Brazing Sheet

Science.gov (United States)

Benoit, M. J.; Whitney, M. A.; Wells, M. A.; Jin, H.; Winkler, S.

2017-10-01

Warm forming has previously proven to be a promising manufacturing route to improve formability of Al brazing sheets used in automotive heat exchanger production; however, the impact of warm forming on subsequent brazing has not previously been studied. In particular, the interaction between liquid clad and solid core alloys during brazing through the process of liquid film migration (LFM) requires further understanding. Al brazing sheet comprised of an AA3003 core and AA4045 clad alloy, supplied in O and H24 tempers, was stretched between 0 and 12 pct strain, at room temperature and 523K (250 °C), to simulate warm forming. Brazeability was predicted through thermal and microstructure analysis. The rate of solid-liquid interactions was quantified using thermal analysis, while microstructure analysis was used to investigate the opposing processes of LFM and core alloy recrystallization during brazing. In general, liquid clad was consumed relatively rapidly and LFM occurred in forming conditions where the core alloy did not recrystallize during brazing. The results showed that warm forming could potentially impair brazeability of O temper sheet by extending the regime over which LFM occurs during brazing. No change in microstructure or thermal data was found for H24 sheet when the forming temperature was increased, and thus warm forming was not predicted to adversely affect the brazing performance of H24 sheet.

Evolution of the Eurasian Ice Sheets during the Last Deglaciation (25-10 kyr)

Science.gov (United States)

Hughes, A. L. C.; Gyllencreutz, R.; Mangerud, J.; Svendsen, J. I.; Lohne, Ø. S.

2014-12-01

Both the timing of maximum extent and subsequent pace of retreat of the interconnected Eurasian (British-Irish, Scandinavian, Svalbard-Barents-Kara Sea) Ice Sheets were spatially variable likely reflecting contrasts in response to forcing mechanisms, geographical settings and glacial dynamics both between individual ice sheets and ice-sheet sectors. For example the maximum limit along the western continental shelf edge was reached up to 3,000 years earlier than the maximum, mainly terrestrial, limits in the east. We present new time-slice reconstructions of the ice-sheet evolution through the last deglaciation based on a compiled chronology of over 5,000 dates and published ice-margin positions. Ice-sheet margins are depicted every 1,000 years (25-10 kyr) and include uncertainty estimates (represented by maximum, minimum and most-credible lines). The new ice-sheet scale reconstructions summarise and provide the means for direct comparison of the empirical geological record against simulations of the deglacial ice-sheet evolution from numerical and isostatic ice-sheet modelling and the timing of abrupt events observed in deglacial climate and ocean records. The reconstruction process has identified both instances of conflicting evidence and gaps in the geological record that should be a focus for future studies. This work is part of an on-going project to reconstruct the changing limits of the Eurasian Ice Sheets through the last glacial cycle (www.uib.no/project/dated).

Sausage mode instability of thin current sheets as a cause of magnetospheric substorms

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J. Büchner

Full Text Available Observations have shown that, prior to substorm explosions, thin current sheets are formed in the plasma sheet of the Earth's magnetotail. This provokes the question, to what extent current-sheet thinning and substorm onsets are physically, maybe even causally, related. To answer this question, one has to understand the plasma stability of thin current sheets. Kinetic effects must be taken into account since particle scales are reached in the course of tail current-sheet thinning. We present the results of theoretical investigations of the stability of thin current sheets and about the most unstable mode of their decay. Our conclusions are based upon a non-local linear dispersion analysis of a cross-magnetic field instability of Harris-type current sheets. We found that a sausage-mode bulk current instability starts after a sheet has thinned down to the ion inertial length. We also present the results of three-dimensional electromagnetic PIC-code simulations carried out for mass ratios up to M_i / m_e=64. They verify the linearly predicted properties of the sausage mode decay of thin current sheets in the parameter range of interest.

Key words. Magnetospheric physics (plasma waves and instabilities; storms and substorms · Space plasma physics (magnetic reconnection

Thermal vibration of a rectangular single-layered graphene sheet with quantum effects

International Nuclear Information System (INIS)

Wang, Lifeng; Hu, Haiyan

2014-01-01

The thermal vibration of a rectangular single-layered graphene sheet is investigated by using a rectangular nonlocal elastic plate model with quantum effects taken into account when the law of energy equipartition is unreliable. The relation between the temperature and the Root of Mean Squared (RMS) amplitude of vibration at any point of the rectangular single-layered graphene sheet in simply supported case is derived first from the rectangular nonlocal elastic plate model with the strain gradient of the second order taken into consideration so as to characterize the effect of microstructure of the graphene sheet. Then, the RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet simply supported on an elastic foundation is derived. The study shows that the RMS amplitude of the rectangular single-layered graphene sheet predicted from the quantum theory is lower than that predicted from the law of energy equipartition. The maximal relative difference of RMS amplitude of thermal vibration appears at the sheet corners. The microstructure of the graphene sheet has a little effect on the thermal vibrations of lower modes, but exhibits an obvious effect on the thermal vibrations of higher modes. The quantum effect is more important for the thermal vibration of higher modes in the case of smaller sides and lower temperature. The relative difference of maximal RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet decreases monotonically with an increase of temperature. The absolute difference of maximal RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet increases slowly with the rising of Winkler foundation modulus.

2012 Swimming Season Fact Sheets

Science.gov (United States)

To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

Nutritional Supplements for Strength Power Athletes

Science.gov (United States)

Wilborn, Colin

Over the last decade research involving nutritional supplementation and sport performance has increased substantially. Strength and power athletes have specific needs to optimize their performance. Nutritional supplementation cannot be viewed as a replacement for a balanced diet but as an important addition to it. However, diet and supplementation are not mutually exclusive, nor does one depend on the other. Strength and power athletes have four general areas of supplementation needs. First, strength athletes need supplements that have a direct effect on performance. The second group of supplements includes those that promote recovery. The third group comprises the supplements that enhance immune function. The last group of supplements includes those that provide energy or have a direct effect on the workout. This chapter reviews the key supplements needed to optimize the performance and training of the strength athlete.