Sample records for case study material

  1. CRIS Case Study Materials in Ethical Decision Making.

    ERIC Educational Resources Information Center

    Blanning, James R.

    Designed for secondary-level classroom discussion, these materials contain nine, short case studies of ethical dilemmas. The cast studies focus mainly on incidents and issues relevant to high school students. Discussion questions for each case study require students to examine the case, discuss the issue, and make an ethical decision about how…

  2. Arc Jet Testing of Thermal Protection Materials: 3 Case Studies

    NASA Technical Reports Server (NTRS)

    Johnson, Sylvia; Conley, Joe

    2015-01-01

    Arc jet testing is used to simulate entry to test thermal protection materials. This paper discusses the usefulness of arc jet testing for 3 cases. Case 1 is MSL and PICA, Case 2 is Advanced TUFROC, and Case 3 is conformable ablators.

  3. Developing, Implementing and Evaluating Case Studies in Materials Science

    ERIC Educational Resources Information Center

    Davis, Claire; Wilcock, Elizabeth

    2005-01-01

    The use of case studies to teach materials science undergraduates is an exciting and interesting educational approach. As well as helping learners to connect theory and practice, the case method is also useful for creating an active learning environment, developing key skills and catering for a range of different learning styles. This paper…

  4. Screening of pollution control and clean-up materials for river chemical spills using the multiple case-based reasoning method with a difference-driven revision strategy.

    PubMed

    Liu, Rentao; Jiang, Jiping; Guo, Liang; Shi, Bin; Liu, Jie; Du, Zhaolin; Wang, Peng

    2016-06-01

    In-depth filtering of emergency disposal technology (EDT) and materials has been required in the process of environmental pollution emergency disposal. However, an urgent problem that must be solved is how to quickly and accurately select the most appropriate materials for treating a pollution event from the existing spill control and clean-up materials (SCCM). To meet this need, the following objectives were addressed in this study. First, the material base and a case base for environment pollution emergency disposal were established to build a foundation and provide material for SCCM screening. Second, the multiple case-based reasoning model method with a difference-driven revision strategy (DDRS-MCBR) was applied to improve the original dual case-based reasoning model method system, and screening and decision-making was performed for SCCM using this model. Third, an actual environmental pollution accident from 2012 was used as a case study to verify the material base, case base, and screening model. The results demonstrated that the DDRS-MCBR method was fast, efficient, and practical. The DDRS-MCBR method changes the passive situation in which the choice of SCCM screening depends only on the subjective experience of the decision maker and offers a new approach to screening SCCM.

  5. Physics of Materials.

    ERIC Educational Resources Information Center

    Archenhold, W. F.; And Others

    1987-01-01

    Describes a new high school physics option in Great Britain which uses the model of a technological approach to the study of materials. Discusses the components of the program, including the development of a student book for independent learning and six case studies. Provides a case study about turbine blades. (TW)

  6. Acousto-ultrasonics to Assess Material and Structural Properties

    NASA Technical Reports Server (NTRS)

    Kautz, Harold E.

    2002-01-01

    This report was created to serve as a manual for applying the Acousto-Ultrasonic NDE method, as practiced at NASA Glenn, to the study of materials and structures for a wide range of applications. Three state of the art acousto-ultrasonic (A-U) analysis parameters, ultrasonic decay (UD) rate, mean time (or skewing factor, "s"), and the centroid of the power spectrum, "f(sub c)," have been studied and applied at GRC for NDE interrogation of various materials and structures of aerospace interest. In addition to this, a unique application of Lamb wave analysis is shown. An appendix gives a brief overview of Lamb Wave analysis. This paper presents the analysis employed to calculate these parameters and the development and reasoning behind their use. It also discusses the planning of A-U measurements for materials and structures to be studied. Types of transducer coupling are discussed including contact and non-contact via laser and air. Experimental planning includes matching transducer frequency range to material and geometry of the specimen to be studied. The effect on results of initially zeroing the DC component of the ultrasonic waveform is compared with not doing so. A wide range of interrogation problems are addressed via the application of these analysis parameters to real specimens is shown for five cases: Case 1: Differences in density in [0] SiC/RBSN ceramic matrix composite. Case 2: Effect of tensile fatigue cycling in [+/-45] SiC/SiC ceramic matrix composite. Case 3: Detecting creep life, and failure, in Udimet 520 Nickel-Based Super Alloy. Case 4: Detecting Surface Layer Formation in T-650-35/PMR-15 Polymer Matrix Composites Panels due to Thermal Aging. Case 5: Detecting Spin Test Degradation in PMC Flywheels. Among these cases a wide range of materials and geometries are studied.

  7. Study on Thermal Conductivity of Personal Computer Aluminum-Magnesium Alloy Casing

    NASA Astrophysics Data System (ADS)

    Liao, MeiHong

    With the rapid development of computer technology, micro-state atoms by simulating the movement of material to analyze the nature of the macro-state have become an important subject. Materials, especially aluminium-magnesium alloy materials, often used in personal computer case, this article puts forward heat conduction model of the material, and numerical methods of heat transfer performance of the material.

  8. Resident Perspectives of an Interactive Case Review Following Independent Didactic Study as a Method of Teaching a Pediatric Imaging Curriculum.

    PubMed

    Rozenberg, Aleksandr; Dheer, Sachin; Nazarian, Levon N; Long, Suzanne S

    The ABR has recently changed the format of the board examination, in which the oral examination was replaced by a computer based multiple-choice test. The purpose of this study was to determine resident's perceptions of a new conference resembling the new ABR format. Residents were requested to review a series of didactic pediatric imaging presentations prior to attending case conference. During conference, unknown cases reflecting the subject matter from the didactic presentations were presented along with multiple-choice questions. We then surveyed resident perspectives after each case conference. Between 14 and 18 residents were surveyed at the end of each subspecialty case review presentation. About 94% of resident respondents felt that the independent didactic study followed by an interactive case review session would better prepare them for the ABR certification exams, compared to didactic lectures alone. Furthermore, 95% of the respondents indicated that they preferred the independent didactic review followed by interactive case review versus didactic lecture alone. Most the respondents (85%) felt that combining independent didactic review with interactive unknown case sessions made the material more interesting and provided greater understanding of the material. There was no statistically significant difference in the distribution of answers across the subspecialty sessions (p > .05). Radiology residents favorably reviewed the combination of independent review of didactic material prior to interactive case review. Material presented in this fashion is felt to be more interesting and is thought to result in enhanced understanding of pediatric radiology material. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. From waste to sustainable materials management: Three case studies of the transition journey.

    PubMed

    Silva, Angie; Rosano, Michele; Stocker, Laura; Gorissen, Leen

    2017-03-01

    Waste policy is increasingly moving on from the 'prevention of waste' to a 'sustainable materials policy' focused agenda recognising individual wastes as a resource. In order to comparatively analyse policy developments in enhanced waste management, three case studies were selected; San Francisco's Zero Waste Program, Flanders's Sustainable Materials Management Initiative and Japan's Sound Material-Cycle Society Plan. These case studies were chosen as an opportunity to investigate the variety of leading approaches, governance structures, and enhanced waste policy outcomes, emerging globally. This paper concludes that the current transitional state of waste management across the world, is only in the first leg of the journey towards Circular Economy closed loop production models of waste as a resource material. It is suggested that further development in government policy, planning and behaviour change is required. A focus on material policy and incorporating multiple front runners across industry and knowledge institutions are offered as potential directions in the movement away from end-pipe land-fill solutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Case Study: Guidelines for Producing Videos to Accompany Flipped Cases

    ERIC Educational Resources Information Center

    Prud'homme-Généreux, Annie; Schiller, Nancy A.; Wild, John H.; Herreid, Clyde Freeman

    2017-01-01

    Three years ago, the "National Center for Case Study Teaching in Science" (NCCSTS) was inspired to merge the case study and flipped classroom approaches. The resulting project aimed to create the materials required to teach a flipped course in introductory biology by assigning videos as homework and case studies in the classroom. Three…

  11. Working towards Best Practice in Assessment. A Case Study Approach to Some Issues Concerning Competency-Based Assessment in the Vocational Education and Training Sector.

    ERIC Educational Resources Information Center

    Bloch, Barbara; Thomson, Peter

    Between July and November 1993, a cross-section of Australia's school- and workplace-based vocational education and training programs was studied to identify programs using innovative assessment strategies and materials. As innovative strategies/materials were identified, the study methodology was revised and a case study approach was adopted. The…

  12. Science of Materials: A Case Study of Intentional Teaching in the Early Years

    ERIC Educational Resources Information Center

    Hackling, Mark; Barratt-Pugh, Caroline

    2012-01-01

    Australia's Early Years Learning Framework and leading international researchers argue for more intentional and purposeful teaching of science in the early years. This case study of exemplary practice illustrates intentional teaching of science materials which opened-up learning opportunities in literacy and number. Student-led hands-on…

  13. Teacher Knowledge, Curriculum Materials, and Quality of Instruction: Lessons Learned and Open Issues

    ERIC Educational Resources Information Center

    Hill, Heather C.; Charalambous, Charalambos Y.

    2012-01-01

    This paper draws on four case studies to perform a cross-case analysis investigating the unique and joint contribution of mathematical knowledge for teaching (MKT) and curriculum materials to instructional quality. As expected, it was found that both MKT and curriculum materials matter for instruction. The contribution of MKT was more prevalent in…

  14. Molecular testing in lung cancer: fine-needle aspiration specimen adequacy and test prioritization prior to the CAP/IASLC/AMP Molecular Testing Guideline publication.

    PubMed

    Rafael, Oana C; Aziz, Mohamed; Raftopoulos, Harry; Vele, Oana E; Xu, Weisheng; Sugrue, Chiara

    2014-06-01

    Subtyping of lung carcinoma with immunohistochemistry is essential for diagnosis, whereas molecular testing (MT) is required for therapy guidance. In the current study, the authors report on MT performed on fine-needle aspiration specimens at the study institution over a 2-year period preceding the April 2013 College of American Pathologists (CAP)/International Association for the Study of Lung Cancer (IASLC)/Association for Molecular Pathology (AMP) Molecular Testing Guideline (MTG) publication. The database of the study institution was retrospectively queried for cases of lung and thoracic/lower cervical lymph node fine-needle aspiration specimens for 2011 through 2012. Of 246 selected cases, 26 featured a limited amount of material in cell blocks. MT increased significantly between 2011 and 2012 and was requested in 39.4% of cases (97 of 246 cases): 86 of those cases had at least 1 MT result and 11 had insufficient material for any MT. Anaplastic lymphoma kinase (ALK) testing was performed in 9 cases in which DNA was insufficient for epidermal growth factor receptor (EGFR) testing. In addition, 13 cases of adenocarcinoma/non-small cell lung carcinoma had at least 1 MT canceled because of insufficient DNA, but at the same time had an average of 3.46 immunohistochemical stains performed. Of all the cytology specimens, 10.6% featured limited material; however, no universally accepted testing sequence priority was available at the time the study was performed. As per the MTG, MT should take precedence over immunohistochemistry in cases of adenocarcinoma/non-small cell lung carcinoma. Approximately 5.3% of the specimens in the current study had insufficient material for MT while having multiple stains performed instead. The MTG also recommend performing EGFR before ALK testing; the authors found 9 cases with insufficient material for EGFR testing that had ALK testing performed. The results of the current study underscore the need for a testing prioritization algorithm in view of the MTG publication to serve as reference for both clinicians and pathologists. © 2014 American Cancer Society.

  15. Treatment of Acute Periodontal Abscesses Using the Biofilm Decontamination Approach: A Case Report Study.

    PubMed

    Pini-Prato, Giovanpaolo; Magnani, Cristina; Rotundo, Roberto

    2016-01-01

    The aim of this preliminary study was to show the treatment effect of the biofilm decontamination approach on acute periodontal abscesses. Clinical cases showing acute periodontitis were treated using an oral tissue decontaminant material that contains a concentrated aqueous mixture of hydroxybenzenesulfonic and hydroxymethoxybenzene acids and sulfuric acid. The material was positioned into the pocket on the root surface and left in the site for 30 seconds. No instrumentation was performed before the treatment. No systemic or local antibiotics were used in any of the cases. A questionnaire was used for each patient to record the pain/discomfort felt when the material was administered. All of the treated cases healed well and very rapidly. The infections were quickly resolved without complications, and the pockets associated with marginal tissue recession were also reduced. The momentary pain upon introduction of the material was generally well tolerated in the nonsurgically treated cases, and it completely disappeared after a few seconds. The biofilm decontamination approach seems to be a very promising technique for the treatment of acute periodontal abscess. The local application of this material avoids the use of systemic or local antibiotics.

  16. Cases and Materials on Women and the Law for GS 200: Introduction to Women's Studies.

    ERIC Educational Resources Information Center

    Knowles, Marjorie Fine, Ed.

    Cases and materials used in an undergraduate course, "Women and the Law," are divided to cover women and the Constitution of the U.S. (including the Equal Rights Amendment), the Supreme Court Abortion Decision, and the contemporary legal status of women including employment, education, and criminal law. Fifteen cases highlight the issues…

  17. Understanding transferable supply chain lessons and practices to a "high-tech" industry using guidelines from a primary sector industry: a case study in the food industry supply chain.

    PubMed

    Coronado Mondragon, Adrian E; Coronado Mondragon, Christian E; Coronado, Etienne S

    2015-01-01

    Flexibility and innovation at creating shapes, adapting processes, and modifying materials characterize composites materials, a "high-tech" industry. However, the absence of standard manufacturing processes and the selection of materials with defined properties hinder the configuration of the composites materials supply chain. An interesting alternative for a "high-tech" industry such as composite materials would be to review supply chain lessons and practices in "low-tech" industries such as food. The main motivation of this study is to identify lessons and practices that comprise innovations in the supply chain of a firm in a perceived "low-tech" industry that can be used to provide guidelines in the design of the supply chain of a "high-tech" industry, in this case composite materials. This work uses the case study/site visit with analogy methodology to collect data from a Spanish leading producer of fresh fruit juice which is sold in major European markets and makes use of a cold chain. The study highlights supply base management and visibility/traceability as two elements of the supply chain in a "low-tech" industry that can provide guidelines that can be used in the configuration of the supply chain of the composite materials industry.

  18. Arsenic Removal from Drinking Water

    EPA Science Inventory

    Web cast presentation covered six topics: 1), Arsenic Chemistry, 2), Technology Selection/Arsenic Demonstration Program, 3), Case Study 1, 4), Case Study 2,5), Case Study 3, and 6), Media Regeneration Project. The presentation consists of material presented at other training sess...

  19. Case Report: Analytical Electron Microscopy of Lung Granulomas Associated with Exposure to Coating Materials Carried by Glass Wool Fibers

    PubMed Central

    Ferreira, Angela S.; Moreira, Valéria B.; Castro, Marcos César S.; Soares, Porfírio J.; Algranti, Eduardo; Andrade, Leonardo R.

    2010-01-01

    Context Man-made vitreous fibers (MMVFs) are noncrystalline inorganic fibrous material used for thermal and acoustical insulation (e.g., rock wool, glass wool, glass microfibers, and refractory ceramic fibers). Neither epidemiologic studies of human exposure nor animal studies have shown a noticeable hazardous effect of glass wools on health. However, MMVFs have been anecdotally associated with granulomatous lung disease in several case reports. Case presentation Here, we describe the case of a patient with multiple bilateral nodular opacities who was exposed to glass wool fibers and coating materials for 7 years. Bronchoalveolar lavage fluid revealed an increased total cell count (predominantly macrophages) with numerous cytoplasmic particles. Lung biopsy showed peribronchiolar infiltration of lymphoid cells and many foreign-body–type granulomas. Alveolar macrophages had numerous round and elongated platelike particles inside the cytoplasm. X-ray microanalysis of these particles detected mainly oxygen/aluminum/silicon and oxygen/magnesium/silicon, compatible with kaolinite and talc, respectively. No elemental evidence for glass fibers was found in lung biopsy. Discussion The contribution of analytical electron microscopy applied in the lung biopsy was imperative to confirm the diagnosis of pneumoconiosis associated with a complex occupational exposure that included both MMVFs and coating materials. Relevance to clinical or professional practice This case study points out the possible participation of other components (coating materials), beyond MMVFs, in the etiology of pneumoconiosis. PMID:20123612

  20. How Do I Manage? An Introduction to Management. Supplementary Material and Workbook.

    ERIC Educational Resources Information Center

    North West Regional Management Centre, Chorley (England).

    This book contains supplementary material for a British self-study course in management designed as an introduction to the course for the Certificate in Management Studies. The materials in this book are learning activities referenced to various topics in the course materials. The nine activities include a case study of a production supervision…

  1. Effectiveness of Written Materials in a Rehabilitative Program for Female Offenders: A Case Study at the Montana Women's Prison

    ERIC Educational Resources Information Center

    Dillon, Laura; Colling, Kyle

    2010-01-01

    This case study of the Therapeutic Community Program at Montana Women's Prison investigates the relationship between inmate reading levels and the self-help materials used for rehabilitative purposes within prison settings. The Therapeutic Community Handbook, published by the Montana Department of Corrections, is used as the primary method of…

  2. THREE GENERATIONS, CASE MATERIALS IN LOW INCOME URBAN LIVING.

    ERIC Educational Resources Information Center

    JEFFERS, CAMILLE

    ONE IN A SERIES OF STUDIES OF THE CHILD REARING STUDY (CRS) OF LOW-INCOME FAMILIES IN WASHINGTON, D.C., THIS BOOKLET PRESENTS CASE MATERIALS TO ILLUSTRATE THE CRS THESIS THAT THERE IS A WIDE VARIABILITY IN BEHAVIOR AND OUTLOOK AMONG THE URBAN POOR, AND SUGGESTS SOME OF THE IMPLICATIONS OF THE CRS FINDINGS FOR PARENT AND FAMILY LIFE EDUCATION.…

  3. Understanding Transferable Supply Chain Lessons and Practices to a “High-Tech” Industry Using Guidelines from a Primary Sector Industry: A Case Study in the Food Industry Supply Chain

    PubMed Central

    Coronado Mondragon, Adrian E.; Coronado, Etienne S.

    2015-01-01

    Flexibility and innovation at creating shapes, adapting processes, and modifying materials characterize composites materials, a “high-tech” industry. However, the absence of standard manufacturing processes and the selection of materials with defined properties hinder the configuration of the composites materials supply chain. An interesting alternative for a “high-tech” industry such as composite materials would be to review supply chain lessons and practices in “low-tech” industries such as food. The main motivation of this study is to identify lessons and practices that comprise innovations in the supply chain of a firm in a perceived “low-tech” industry that can be used to provide guidelines in the design of the supply chain of a “high-tech” industry, in this case composite materials. This work uses the case study/site visit with analogy methodology to collect data from a Spanish leading producer of fresh fruit juice which is sold in major European markets and makes use of a cold chain. The study highlights supply base management and visibility/traceability as two elements of the supply chain in a “low-tech” industry that can provide guidelines that can be used in the configuration of the supply chain of the composite materials industry. PMID:25821848

  4. Foreign body aspiration in dentistry: a review.

    PubMed

    Cameron, S M; Whitlock, W L; Tabor, M S

    1996-08-01

    This article reviews the dangers of aspirating foreign bodies of dental origin. Two illustrative cases are presented, including an unusual case involving aspiration of an elastomeric impression material. The authors describe the techniques used to identify the foreign body. A radiodensimetric study of four impression materials demonstrates the difficulty of identifying most impression materials. The authors also present some strategies for reducing the risk of aspiration during dental procedures.

  5. Leakage of radioactive materials from particle accelerator facilities by non-radiation disasters like fire and flooding and its environmental impacts

    NASA Astrophysics Data System (ADS)

    Lee, A.; Jung, N. S.; Mokhtari Oranj, L.; Lee, H. S.

    2018-06-01

    The leakage of radioactive materials generated at particle accelerator facilities is one of the important issues in the view of radiation safety. In this study, fire and flooding at particle accelerator facilities were considered as the non-radiation disasters which result in the leakage of radioactive materials. To analyse the expected effects at each disaster, the case study on fired and flooded particle accelerator facilities was carried out with the property investigation of interesting materials presented in the accelerator tunnel and the activity estimation. Five major materials in the tunnel were investigated: dust, insulators, concrete, metals and paints. The activation levels on the concerned materials were calculated using several Monte Carlo codes (MCNPX 2.7+SP-FISPACT 2007, FLUKA 2011.4c and PHITS 2.64+DCHAIN-SP 2001). The impact weight to environment was estimated for the different beam particles (electron, proton, carbon and uranium) and the different beam energies (100, 430, 600 and 1000 MeV/nucleon). With the consideration of the leakage path of radioactive materials due to fire and flooding, the activation level of selected materials, and the impacts to the environment were evaluated. In the case of flooding, dust, concrete and metal were found as a considerable object. In the case of fire event, dust, insulator and paint were the major concerns. As expected, the influence of normal fire and flooding at electron accelerator facilities would be relatively low for both cases.

  6. Characterization of welded HP 9-4-30 steel for the advanced solid rocket motor

    NASA Technical Reports Server (NTRS)

    Watt, George William

    1990-01-01

    Solid rocket motor case materials must be high-strength, high-toughness, weldable alloys. The Advanced Solid Rocket Motor (ASRM) cases currently being developed will be made from a 9Ni-4Co quench and temper steel called HP 9-4-30. These ultra high-strength steels must be carefully processed to give a very clean material and a fine grained microstructure, which insures excellent ductility and toughness. The HP 9-4-30 steels are vacuum arc remelted and carbon deoxidized to give the cleanliness required. The ASRM case material will be formed into rings and then welded together to form the case segments. Welding is the desired joining technique because it results in a lower weight than other joining techniques. The mechanical and corrosion properties of the weld region material were fully studied.

  7. Using Online Case Studies to Enhance Teacher Preparation

    ERIC Educational Resources Information Center

    Richman, Laila

    2015-01-01

    The purpose of this study was to assess the impact interactive, online case studies have on learning for preservice teachers. More specifically, it evaluated whether the use of online case studies in instruction could enhance the level of knowledge the preservice teacher gained from the content material. This study utilized a nonequivalent group,…

  8. Elementary Students' Learning of Materials Science Practices through Instruction Based on Engineering Design Tasks

    ERIC Educational Resources Information Center

    Wendell, Kristen Bethke; Lee, Hee-Sun

    2010-01-01

    Materials science, which entails the practices of selecting, testing, and characterizing materials, is an important discipline within the study of matter. This paper examines how third grade students' materials science performance changes over the course of instruction based on an engineering design challenge. We conducted a case study of nine…

  9. The Analysis of a Murder, a Case Study

    ERIC Educational Resources Information Center

    Dinan, Frank J.; Szczepankiewicz, Steven H.; Carnaham, Melinda; Colvin, Michael T.

    2007-01-01

    The analysis of a Murder case study can be used in general chemistry or nonscience major chemistry courses to teach data handling and analysis in a non-laboratory context. This case study will help students to respond more enthusiastically and with more interest to a set of material placed before them related to a real case rather than…

  10. Post-impact behavior of composite solid rocket motor cases

    NASA Technical Reports Server (NTRS)

    Highsmith, Alton L.

    1992-01-01

    In recent years, composite materials have seen increasing use in advanced structural applications because of the significant weight savings they offer when compared to more traditional engineering materials. The higher cost of composites must be offset by the increased performance that results from reduced structural weight if these new materials are to be used effectively. At present, there is considerable interest in fabricating solid rocket motor cases out of composite materials, and capitalizing on the reduced structural weight to increase rocket performance. However, one of the difficulties that arises when composite materials are used is that composites can develop significant amounts of internal damage during low velocity impacts. Such low velocity impacts may be encountered in routine handling of a structural component like a rocket motor case. The ability to assess the reduction in structural integrity of composite motor cases that experience accidental impacts is essential if composite rocket motor cases are to be certified for manned flight. The study described herein was an initial investigation of damage development and reduction of tensile strength in an idealized composite subjected to low velocity impacts.

  11. DEVELOPMENT AND APPLICATION OF MATERIALS PROPERTIES FOR FLAW STABILITY ANALYSIS IN EXTREME ENVIRONMENT SERVICE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sindelar, R; Ps Lam, P; Andrew Duncan, A

    Discovery of aging phenomena in the materials of a structure may arise after its design and construction that impact its structural integrity. This condition can be addressed through a demonstration of integrity with the material-specific degraded conditions. Two case studies of development of fracture and crack growth property data, and their application in development of in-service inspection programs for nuclear structures in the defense complex are presented. The first case study covers the development of fracture toughness properties in the form of J-R curves for rolled plate Type 304 stainless steel with Type 308 stainless steel filler in the applicationmore » to demonstrate the integrity of the reactor tanks of the heavy water production reactors at the Savannah River Site. The fracture properties for the base, weld, and heat-affected zone of the weldments irradiated at low temperatures (110-150 C) up to 6.4 dpa{sub NRT} and 275 appm helium were developed. An expert group provided consensus for application of the irradiated properties for material input to acceptance criteria for ultrasonic examination of the reactor tanks. Dr. Spencer H. Bush played a lead advisory role in this work. The second case study covers the development of fracture toughness for A285 carbon steel in high level radioactive waste tanks. The approach in this case study incorporated a statistical experimental design for material testing to address metallurgical factors important to fracture toughness. Tolerance intervals were constructed to identify the lower bound fracture toughness for material input to flaw disposition through acceptance by analysis.« less

  12. Determining Crack Tip Field Parameters for Elastic-Plastic Materials via an Estimation Scheme

    DTIC Science & Technology

    1981-07-01

    of the Materials Laboratory was the Project Monitor for this study of the application of the Nonlinear Fracture Mechanics (NLFM) parameters to the...fracture mechanics (LEFM) is applicable . If the plastic zone size is large, compared to the case of small scale yielding, LEFM is not applicable . The...above HRR field equations are applicable only for the case of stationary cracks. 2.2 PARAMETER DETERMINATION For elastic-plastic materials, the

  13. A Study of False-Positive and False-Negative Error Rates in Cartridge Case Comparisons

    DTIC Science & Technology

    2014-04-07

    materials for the study, in particular Vicki Sieve. 3 Abstract: This report provides the details for a study designed to...participate in ASCLD were provided with 15 sets of 3 known + 1 unknown cartridge cases fired from a collection of 25 new Ruger SR9 handguns . The...answer sheet allowing for the AFTE range of conclusions, and return shipping materials . They were also asked to assess how many of the 3 knowns were

  14. Effects of resource-dependent cannibalism on population size distribution and individual life history in a case-bearing caddisfly

    PubMed Central

    Okuda, Noboru

    2018-01-01

    Resource availability often determines the intensity of cannibalism, which has a considerable effect on population size distribution and individual life history. Larvae of the caddisfly Psilotreta kisoensis build portable cases from sedimentary sands and often display cannibalism. For this species, the availability of preferable case material is a critical factor that affects larval fitness, and material is locally variable depending on the underlying geology. In this study, we investigated how sand quality as a case material determines cannibalism frequency among larvae and, in turn, how the differential cannibalism frequency affects the body-size distribution and voltinism. Rearing experiments within a cohort revealed that a bimodal size distribution developed regardless of material quality. However, as the preferable material became abundant, the proportion of larger to smaller individuals increased. Consecutive experiments suggested that smaller larvae were more frequently cannibalized by larger ones and excluded from the population when preferable smooth material was abundant. This frequent cannibalism resulted in a bimodal size distribution with a significantly higher proportion of larger compared to smaller individuals. The size-dependent cannibalism was significantly suppressed when the larvae were raised in an environment with a scarcity of the preferable case material. This is probably because larvae cannot enjoy the benefit of rapid growth by cannibalism due to the difficulties in enlarging their case. At low cannibalism the growth of smaller individuals was stunted, and this was probably due to risk of cannibalism by larger individuals. This growth reduction in small individuals led to a bimodal size-distribution but with a lower proportion of larger to smaller individuals compared to at high cannibalism. A field study in two streams showed a similar size distribution of larvae as was found in the rearing experiment. The bimodal ratio has consequences for life history, since a size-bimodal population causes a cohort splitting: only larvae that were fully grown at 1 year had a univoltine life cycle, whereas larvae with a stunted growth continued their larval life for another year (semivoltine). This study suggests that availability of preferable case building material is an important factor that affects cannibalism, which in turn affects larval population size structure and cohort splitting. PMID:29466375

  15. Effects of resource-dependent cannibalism on population size distribution and individual life history in a case-bearing caddisfly.

    PubMed

    Okano, Jun-Ichi; Okuda, Noboru

    2018-01-01

    Resource availability often determines the intensity of cannibalism, which has a considerable effect on population size distribution and individual life history. Larvae of the caddisfly Psilotreta kisoensis build portable cases from sedimentary sands and often display cannibalism. For this species, the availability of preferable case material is a critical factor that affects larval fitness, and material is locally variable depending on the underlying geology. In this study, we investigated how sand quality as a case material determines cannibalism frequency among larvae and, in turn, how the differential cannibalism frequency affects the body-size distribution and voltinism. Rearing experiments within a cohort revealed that a bimodal size distribution developed regardless of material quality. However, as the preferable material became abundant, the proportion of larger to smaller individuals increased. Consecutive experiments suggested that smaller larvae were more frequently cannibalized by larger ones and excluded from the population when preferable smooth material was abundant. This frequent cannibalism resulted in a bimodal size distribution with a significantly higher proportion of larger compared to smaller individuals. The size-dependent cannibalism was significantly suppressed when the larvae were raised in an environment with a scarcity of the preferable case material. This is probably because larvae cannot enjoy the benefit of rapid growth by cannibalism due to the difficulties in enlarging their case. At low cannibalism the growth of smaller individuals was stunted, and this was probably due to risk of cannibalism by larger individuals. This growth reduction in small individuals led to a bimodal size-distribution but with a lower proportion of larger to smaller individuals compared to at high cannibalism. A field study in two streams showed a similar size distribution of larvae as was found in the rearing experiment. The bimodal ratio has consequences for life history, since a size-bimodal population causes a cohort splitting: only larvae that were fully grown at 1 year had a univoltine life cycle, whereas larvae with a stunted growth continued their larval life for another year (semivoltine). This study suggests that availability of preferable case building material is an important factor that affects cannibalism, which in turn affects larval population size structure and cohort splitting.

  16. [Pathological and biochemical studies of 30 Niigata autopsy cases related to Minamata disease].

    PubMed

    Eto, Komyo; Takahashi, Hitoshi; Kakita, Akiyoshi; Tokunaga, Hidehiro; Yasutake, Akira; Nakano, Atsuhiro; Sawada, Masumi; Kinjo, Yoshihide

    2007-01-01

    To reevaluate pathologically and biochemically 30 autopsy cases related to Minamata disease (MD) in Niigata Prefecture (NP) and compare the findings with those of autopsy cases related to MD in Kumamoto Prefecture (KP). Recently, a set of pathological materials of these 30 autopsy cases has been sent from the Brain Research Institute at the University of Niigata to the National Institute for Minamata Disease (NIMD). The materials from each autopsy case were reexamined at the NIMD. There were no postnatal and fetal cases of MD in the NP autopsy materials. The contents of total mercury (T-Hg), methylmercury (Me-Hg), inorganic mercury (I-Hg) and selenium were measured in the organs of cerebrum, cerebellum, liver and kidney. The contents of T-Hg, Me-Hg and I-Hg were much higher in two cases than in controls. The pathological findings leading to the diagnosis of MD in the NP cases were essentially the same as those in KP, including the peripheral nerve lesions. In the most severely affected case of MD in NP, formation of multiple vacuoles of various sizes was observed in the cerebellar cortex, which was never encountered in the KP cases. The KP lesions were similar to that observed in an acute case of Me-Hg-treated common marmoset studied in the NIMD. The pathological features were essentially the same between the adult cases of MD in NP and KP.

  17. Nanostructured Thermal Protection Systems for Space Exploration Missions

    NASA Technical Reports Server (NTRS)

    Arnold, J. O.; Chen, Y. K.; Squire, T.; Srivastava, D.; Allen, G., Jr.; Stackpoole, M.; Goldstein, H. E.; Venkatapathy, E.; Loomis, M. P.

    2005-01-01

    Strong research and development programs in nanotechnology and Thermal Protection Systems (TPS) exist at NASA Ames. Conceptual studies have been undertaken to determine if new, nanostructured materials (composites of existing TPS materials and nanostructured composite fibers) could improve the performance of TPS. To this end, we have studied various candidate heatshields, some composed of existing TPS materials (with known material properties), to provide a baseline for comparison with others that are admixtures of such materials and a nanostructured material. In the latter case, some assumptions were made about the thermal conductivity and strength of the admixture, relative to the baseline TPS material. For the purposes of this study, we have made the conservative assumption that only a small fraction of the remarkable properties of carbon nanotubes (for example) will be realized in the material properties of the admixtures employing them. The heatshields studied included those for Sharp leading edges (appropriate to out-of-orbit entry and aero-maneuvering), probes, an out-of-orbit Apollo Command Module (as a surrogate for NASA's new Crew Exploration Vehicle [CEV]), a Mars Sample Return Vehicle and a large heat shield for Mars aerocapture missions. We report on these conceptual studies, which show that in some cases (not all), significant improvements in the TPS can be achieved through the use of nanostructured materials.

  18. Case study #3 -- severe scaling of an interstate bridge deck, and Potentially reactive carbonate aggregates, progress report #6 (partial): an example of bridge deterioration promoted by alkali-carbonate reaction.

    DOT National Transportation Integrated Search

    1971-01-01

    The project designated "Concrete Durability Studies" comprises case studies of unusual durability, either in kind or extent. These case studies are directed toward situations in which appearances suggest materials or construction rather than structur...

  19. Curriculum Differential Enactment: The Interplay of Teacher, Class, and Curriculum Materials

    ERIC Educational Resources Information Center

    Eisenmann, Tammy

    2011-01-01

    Curriculum materials' developers typically assume the existence of certain general social-educational classroom practices and norms. Conversely, the current study addresses the effects of context on curriculum enactment, focusing on the interrelations between teacher, class and curriculum materials. Each of the two case studies presented herein…

  20. First Preliminary Report on Isolation and Characterization of Novel Acinetobacter spp. in Casing Soil Used for Cultivation of Button Mushroom, Agaricus bisporus (Lange) Imbach

    PubMed Central

    Choudhary, D. K.

    2011-01-01

    Despite evaluation of large number of agroindustrial wastes for their use as casing material for Agaricus bisporus (Lange) Imbach cultivation, scant attention has been given to the importance of biological properties of casing materials. In the present study, an attempt was made to characterize the bacterial flora in casing layer, namely, Farm Yard Manure (FYM) and Spent Mushroom Substrate/spent compost (SMS/SC) (FYM+SC, 3 : 1) and FYM and Vermi Compost (VC) (FYM+VC, 3 : 1), employing partial 16S rDNA sequencing. Available data showed a significant variety of organisms that included Acinetobacter and Pseudomonas of the γ-proteobacteria, that were the most frequently encountered genera. This is the first preliminary report on the microbial diversity of casing soils and demonstrates the presence of Acinetobacter spp. that has not been previously described in casing material. PMID:22007222

  1. Effects of Buckling Knockdown Factor, Internal Pressure and Material on the Design of Stiffened Cylinders

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.

    2010-01-01

    A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.

  2. Open-Ended Cases in Agroecology: Farming and Food Systems in the Nordic Region and the US Midwest

    ERIC Educational Resources Information Center

    Francis, Charles; King, James; Lieblein, Geir; Breland, Tor Arvid; Salomonsson, Lennart; Sriskandarajah, Nadarajah; Porter, Paul; Wiedenhoeft, Mary

    2009-01-01

    Our aim is to describe open-ended case studies for learning real-life problem solving skills, and relate this approach to conventional, closed-ended decision case studies. Teaching methods are open-ended cases in agroecology, an alternative to traditional strategies that lead students through prepared materials and structured discussions to…

  3. Development and Evaluation of English Listening Study Materials for Business People Who Use Mobile Devices: A Case Study

    ERIC Educational Resources Information Center

    Yamada, Masanori; Kitamura, Satoshi; Shimada, Noriko; Utashiro, Takafumi; Shigeta, Katsusuke; Yamaguchi, Etsuji; Harrison, Richard; Yamauchi, Yuhei; Nakahara, Jun

    2011-01-01

    This study aims to verify the effectiveness of English language materials using mobile devices for business people in terms of the effect on motivation, overall learning performance, and practical performance in real business situations. We compared the use of materials developed from business English for a sales department in a company…

  4. The Common Core State Standards and the Role of Instructional Materials: A Case Study on EdReports.org

    ERIC Educational Resources Information Center

    Watt, Michael G.

    2016-01-01

    The purpose of this study was to review research studies investigating the role of instructional materials in relation to the Common Core State Standards and to evaluate whether a new organisation, EdReports.org, founded to evaluate the alignment of instructional materials to the Common Core State Standards, has achieved its objectives. Content…

  5. Experimental pretesting of public health campaigns: a case study.

    PubMed

    Whittingham, Jill; Ruiter, Robert A C; Zimbile, Filippo; Kok, Gerjo

    2008-01-01

    The aim of the present study is to demonstrate the merits of evaluating new public health campaign materials in the developmental phase using an experimental design. This is referred to as experimental pretesting. In practice, most new materials are tested only after they have been distributed using nonexperimental or quasiexperimental designs. In cases where materials are pretested prior to distribution, pretesting is usually done using qualitative research methods such as focus groups. Although these methods are useful, they cannot reliably predict the effectiveness of new campaign materials in a developmental phase. Therefore, we suggest when pretesting new materials, not only qualitative research methods but also experimental research methods must be used. The present study discusses an experimental pretest study of new campaign materials intended for distribution in a national sexually transmitted infection (STI) AIDS prevention campaign in the Netherlands. The campaign material tested was the storyline of a planned television commercial on safe sex. A storyboard that consisted of drawings and text was presented to members of the target population, namely, students between the ages of 14 and 16 enrolled in vocational schools. Results showed positive effects on targeted determinants of safe sexual behavior. The advantages, practical implications, and limitations of experimental pretesting are discussed.

  6. Learning material recommendation based on case-based reasoning similarity scores

    NASA Astrophysics Data System (ADS)

    Masood, Mona; Mokmin, Nur Azlina Mohamed

    2017-10-01

    A personalized learning material recommendation is important in any Intelligent Tutoring System (ITS). Case-based Reasoning (CBR) is an Artificial Intelligent Algorithm that has been widely used in the development of ITS applications. This study has developed an ITS application that applied the CBR algorithm in the development process. The application has the ability to recommend the most suitable learning material to the specific student based on information in the student profile. In order to test the ability of the application in recommending learning material, two versions of the application were created. The first version displayed the most suitable learning material and the second version displayed the least preferable learning material. The results show the application has successfully assigned the students to the most suitable learning material.

  7. DDS: The Dental Diagnostic Simulation System.

    ERIC Educational Resources Information Center

    Tira, Daniel E.

    The Dental Diagnostic Simulation (DDS) System provides an alternative to simulation systems which represent diagnostic case studies of relatively limited scope. It may be used to generate simulated case studies in all of the dental specialty areas with case materials progressing through the gamut of the diagnostic process. The generation of a…

  8. Uniform refraction in negative refractive index materials.

    PubMed

    Gutiérrez, Cristian E; Stachura, Eric

    2015-11-01

    We study the problem of constructing an optical surface separating two homogeneous, isotropic media, one of which has a negative refractive index. In doing so, we develop a vector form of Snell's law, which is used to study surfaces possessing a certain uniform refraction property, in both the near- and far-field cases. In the near-field problem, unlike the case when both materials have positive refractive indices, we show that the resulting surfaces can be neither convex nor concave.

  9. The Integration of Women into Combat Units in the Republic of Korea Army

    DTIC Science & Technology

    2014-12-12

    five generally accepted methods for gathering data in qualitative research : biography, phenomenology , grounded theory , ethnography , and a case study .1... methods of various research materials to address the primary research question. The case studies of the transition and development of female...Data collection for this study used the case study method , as it focused on

  10. The Use of Business Case Studies in Business German Classes.

    ERIC Educational Resources Information Center

    Schutte, Lilith

    The use of business case studies, defined as sophisticated models that present practical business problems and theoretical guidelines that can be used to solve the problems, is discussed. It is suggested that the main advantages of case studies are that they are usually more interesting to read than theoretical materials and they encourage student…

  11. Teaching with the Case Study Method to Promote Active Learning in a Small Molecule Crystallography Course for Chemistry Students

    ERIC Educational Resources Information Center

    Campbell, Michael G.; Powers, Tamara M.; Zheng, Shao-Liang

    2016-01-01

    Implementing the case study method in a practical X-ray crystallography course designed for graduate or upper-level undergraduate chemistry students is described. Compared with a traditional lecture format, assigning small groups of students to examine literature case studies encourages more active engagement with the course material and…

  12. Applying Cases to Solve Ethical Problems: The Significance of Positive and Process-Oriented Reflection

    PubMed Central

    Antes, Alison L.; Thiel, Chase E.; Martin, Laura E.; Stenmark, Cheryl K.; Connelly, Shane; Devenport, Lynn D.; Mumford, Michael D.

    2015-01-01

    This study examined the role of reflection on personal cases for making ethical decisions with regard to new ethical problems. Participants assumed the position of a business manager in a hypothetical organization and solved ethical problems that might be encountered. Prior to making a decision for the business problems, participants reflected on a relevant ethical experience. The findings revealed that application of material garnered from reflection on a personal experience was associated with decisions of higher ethicality. However, whether the case was viewed as positive or negative, and whether the outcomes, process, or outcomes and processes embedded in the experience were examined, influenced the application of case material to the new problem. As expected, examining positive experiences and the processes involved in those positive experiences resulted in greater application of case material to new problems. Future directions and implications for understanding ethical decision-making are discussed. PMID:26257506

  13. Bi-Objective Modelling for Hazardous Materials Road–Rail Multimodal Routing Problem with Railway Schedule-Based Space–Time Constraints

    PubMed Central

    Sun, Yan; Lang, Maoxiang; Wang, Danzhu

    2016-01-01

    The transportation of hazardous materials is always accompanied by considerable risk that will impact public and environment security. As an efficient and reliable transportation organization, a multimodal service should participate in the transportation of hazardous materials. In this study, we focus on transporting hazardous materials through the multimodal service network and explore the hazardous materials multimodal routing problem from the operational level of network planning. To formulate this problem more practicably, minimizing the total generalized costs of transporting the hazardous materials and the social risk along the planned routes are set as the optimization objectives. Meanwhile, the following formulation characteristics will be comprehensively modelled: (1) specific customer demands; (2) multiple hazardous material flows; (3) capacitated schedule-based rail service and uncapacitated time-flexible road service; and (4) environmental risk constraint. A bi-objective mixed integer nonlinear programming model is first built to formulate the routing problem that combines the formulation characteristics above. Then linear reformations are developed to linearize and improve the initial model so that it can be effectively solved by exact solution algorithms on standard mathematical programming software. By utilizing the normalized weighted sum method, we can generate the Pareto solutions to the bi-objective optimization problem for a specific case. Finally, a large-scale empirical case study from the Beijing–Tianjin–Hebei Region in China is presented to demonstrate the feasibility of the proposed methods in dealing with the practical problem. Various scenarios are also discussed in the case study. PMID:27483294

  14. Polarimetric phenomenology in the reflective regime: a case study using polarized hyperspectral data

    NASA Astrophysics Data System (ADS)

    Gibney, Mark

    2016-05-01

    Understanding the phenomenology of polarimetric data is necessary if we want to obtain the maximum benefit when we exploit that data. To first order, polarimetric phenomenology is driven by two things; the target material type (specular or diffuse) and the illuminating source (point (sun) or extended (body emission)). Polarimetric phenomenology can then be broken into three basic categories; ([specular material/sun source], [diffuse/sun], [specular/body]) where we have assigned body emission to the IR passband where materials are generally specular. The task of interest determines the category of interest since the task determines the dominant target material and the illuminating source (eg detecting diffuse targets under trees in VNIR = [diffuse/sun] category). In this paper, a specific case study for the important [diffuse/sun] category will be presented. For the reflective regime (0.3 - 3.0um), the largest polarimetric signal is obtained when the sun illuminates a significant portion of the material BRDF lobe. This naturally points us to problems whose primary target materials are diffuse since the BRDF lobe for specular materials is tiny (low probability of acquiring on the BRDF lobe) and glinty (high probability of saturating the sensor when on lobe). In this case study, we investigated signatures of solar illuminated diffuse paints acquired by a polarimetric hyperspectral sensor. We will discuss the acquisition, reduction and exploitation of that data, and use it to illustrate the primary characteristics of reflective polarimetric phenomenology.

  15. Controversial Suicide Case Using a Submachine Gun with a Sound Suppressor-The Need of Team Work of Forensic Chemistry and Firearm Examiners.

    PubMed

    Brożek-Mucha, Zuzanna; Zdeb, Krzysztof

    2018-05-01

    Evidence materials in a presumed suicide case were studied by a firearm examiner and a forensic chemist. The victim's body with double gunshot wounding in his forehead, a machine gun in the sustained fire mode with a silencer, and four cartridge cases were found. Examinations of the evidence, the case file studies, and experiments dedicated to the case were carried out. Relationships between the placement of cartridge cases and the gun were established using a fast camera. The distributions of gunshot residues on the evidence materials and within the comparative gunshot patterns were studied by means of optical and electron microscopy, X-ray microanalysis, and infrared spectroscopy. The shooting distance was assessed to be 30 cm or more, whereas the greatest distance that could have been achieved by the victim himself was about 11-13 cm. The obtained results supported the version of homicide rather than suicide. © 2017 American Academy of Forensic Sciences.

  16. Embodied Energy and GHG Emissions from Material Use in Conventional and Unconventional Oil and Gas Operations.

    PubMed

    Brandt, Adam R

    2015-11-03

    Environmental impacts embodied in oilfield capital equipment have not been thoroughly studied. In this paper, we present the first open-source model which computes the embodied energy and greenhouse gas (GHG) emissions associated with materials consumed in constructing oil and gas wells and associated infrastructure. The model includes well casing, wellbore cement, drilling mud, processing equipment, gas compression, and transport infrastructure. Default case results show that consumption of materials in constructing oilfield equipment consumes ∼0.014 MJ of primary energy per MJ of oil produced, and results in ∼1.3 gCO2-eq GHG emissions per MJ (lower heating value) of crude oil produced, an increase of 15% relative to upstream emissions assessed in earlier OPGEE model versions, and an increase of 1-1.5% of full life cycle emissions. A case study of a hydraulically fractured well in the Bakken formation of North Dakota suggests lower energy intensity (0.011 MJ/MJ) and emissions intensity (1.03 gCO2-eq/MJ) due to the high productivity of hydraulically fractured wells. Results are sensitive to per-well productivity, the complexity of wellbore casing design, and the energy and emissions intensity per kg of material consumed.

  17. Life cycle assessment for emerging materials: case study of a garden bed constructed from lumber produced with three different copper treatments

    EPA Science Inventory

    Although important data and methodological challenges facing LCA and emerging materials exist, this LCA captures material and process changes that are important drivers of environmental impacts. LCA methods need to be amended to reflect properties of emerging materials that deter...

  18. Diffraction Studies from Minerals to Organics - Lessons Learned from Materials Analyses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whitfield, Pamela S

    2014-01-01

    In many regards the study of materials and minerals by powder diffraction techniques are complimentary, with techniques honed in one field equally applicable to the other. As a long-time materials researcher many of the examples are of techniques developed for materials analysis applied to minerals. However in a couple of cases the study of new minerals was the initiation into techniques later used in materials-based studies. Hopefully they will show that the study of new minerals structures can provide opportunities to add new methodologies and approaches to future problems. In keeping with the AXAA many of the examples have anmore » Australian connection, the materials ranging from organics to battery materials.« less

  19. Thermal Modeling of the Injection of Standard and Thermally Insulated Cored Wire

    NASA Astrophysics Data System (ADS)

    Castro-Cedeno, E.-I.; Jardy, A.; Carré, A.; Gerardin, S.; Bellot, J. P.

    2017-12-01

    Cored wire injection is a widespread method used to perform alloying additions during ferrous and non-ferrous liquid metal treatment. The wire consists of a metal casing that is tightly wrapped around a core of material; the casing delays the release of the material as the wire is immersed into the melt. This method of addition presents advantages such as higher repeatability and yield of cored material with respect to bulk additions. Experimental and numerical work has been performed by several authors on the subject of alloy additions, spherical and cylindrical geometries being mainly considered. Surprisingly this has not been the case for cored wire, where the reported experimental or numerical studies are scarce. This work presents a 1-D finite volume numerical model aimed for the simulation of the thermal phenomena which occurs when the wire is injected into a liquid metal bath. It is currently being used as a design tool for the conception of new types of cored wire. A parametric study on the effect of injection velocity and steel casing thickness for an Al cored wire immersed into a steel melt at 1863 K (1590 °C) is presented. The standard single casing wire is further compared against a wire with multiple casings. Numerical results show that over a certain range of injection velocities, the core contents' release is delayed in the multiple casing when compared to a single casing wire.

  20. Head-on collision of normal shock waves with rigid porous materials

    NASA Astrophysics Data System (ADS)

    Levy, A.; Ben-Dor, G.; Skews, B. W.; Sorek, S.

    1993-08-01

    The head-on collision of a planar shock wave with a rigid porous material has been investigated experimentally in a 75 mm × 75 mm shock tube. The experimental study indicated that unlike the reflection from a flexible porous material (e.g., polyurethane foam) where the transmitted compression waves do not converge to a sharp shock wave, in the case of a rigid porous material (e.g., alumina) the transmitted compression waves do converge to a sharp shock wave, which decays as it propagates along the porous material. In addition to this major difference, many other differences were observed. They are outlined in the following sections. Based on these observations a suggestion modifying the phenomenology of the reflection/interaction process in the case a porous material with large permeability is proposed.

  1. Analytical Tools for the Application of Operational Culture: A Case Study in the Trans-Sahel

    DTIC Science & Technology

    2011-03-28

    Study Team Working Paper 3: Research Methods Discussion for the Study Team Methods229 Generating Empirical Materials In grounded theory ... research I have conducted using these methods . UNCLASSIFIED Analytical Tools for the Application of Operational Culture: A Case Study in the...Survey and a Case Study ,‖ Kjeller, Norway: FFI Glaser, B. G. & Strauss, A. L. (1967). ―The discovery of grounded theory

  2. Biology Teacher and Expert Opinions about Computer Assisted Biology Instruction Materials: A Software Entitled Nucleic Acids and Protein Synthesis

    ERIC Educational Resources Information Center

    Hasenekoglu, Ismet; Timucin, Melih

    2007-01-01

    The aim of this study is to collect and evaluate opinions of CAI experts and biology teachers about a high school level Computer Assisted Biology Instruction Material presenting computer-made modelling and simulations. It is a case study. A material covering "Nucleic Acids and Protein Synthesis" topic was developed as the…

  3. Oman: A Case Study on Research and Development of the Indigenous Building Methods, Materials, Local Skills and Resources. Report Studies ... C.88.

    ERIC Educational Resources Information Center

    Norton, John

    A brief resume of a major study conducted in 1973 identifies the extent to which the indigenous building methods and materials of Oman are capable of meeting the country's contemporary shelter needs, and compares them with alternative materials and techniques being introduced as replacements. Visits to 20 towns and villages in 6 regions and…

  4. Forensic Analysis of a Contact Lens in a Murder Case.

    PubMed

    Zwerling, Charles S

    2016-03-01

    Contact lenses have had rare relevance in trials and/or investigations. After 5 years of burial, orbital remnants were retrieved from an exhumed body and subsequently identified as a key piece of material evidence in a murder trial. The exhumed case materials were evaluated under laboratory conditions and were determined to be contact lens remnants. Contact lens fracture and burial simulation studies were performed to provide additional corroboration of the physical findings of the exhumed contact lens remnants. This material evidence was instrumental in providing factual proof refuting the defendant's testimony in the murder trial. A brief history of contact lens composition and use is provided for understanding the methods and observational results. This forensic case study represents the first published documentation of a contact lens from an exhumed body being used in a murder investigation and establishes an operational procedure for future forensic contact lens examinations. © 2016 American Academy of Forensic Sciences.

  5. A Collection of Papers on Self-Study and Institutional Improvement 1995.

    ERIC Educational Resources Information Center

    North Central Association of Colleges and Schools, Chicago, IL. Commission on Institutions of Higher Education.

    This 11th publication of Annual Meeting papers presents 68 written materials related to invited speakers' oral presentations. The materials address issues of self-study and institutional improvement by institutions of higher education. Chapter 1, "From Self-Study to Site Visit: Case Studies," shares the experiences of a community college…

  6. Managing Training Materials with Structured Text Design.

    ERIC Educational Resources Information Center

    Streit, Les D.; And Others

    1986-01-01

    Describes characteristics of structured text design; benefits of its use in training; benefits for developers of training materials and steps in preparing training materials. A case study illustrating how the structured text design process solved the sales training needs of the Mercedes-Benz Truck Company is presented. (MBR)

  7. Impact damage in filament wound composite bottles

    NASA Technical Reports Server (NTRS)

    Highsmith, Alton L.

    1993-01-01

    Increasingly, composite materials are being used in advanced structural applications because of the significant weight savings they offer when compared to more traditional engineering materials. The higher cost of composites must be offset by the increased performance that results from reduced structural weight if these new materials are to be used effectively. At present, there is considerable interest in fabricating solid rocket motor cases out of composite materials, and capitalizing on the reduced structural weight to increase rocket performance. However, one of the difficulties that arises when composite materials are used is that composites can develop significant amounts of internal damage during low velocity impacts. Such low velocity impacts may be encountered in routine handling of a structural component like a rocket motor case. The ability to assess the reduction in structural integrity of composite motor cases that experience accidental impacts is essential if composite rocket motor cases are to be certified for manned flight. While experimental studies of the post-impact performance of filament wound composite motor cases haven been proven performed (2,3), scaling impact data from small specimens to full scale structures has proven difficult. If such a scaling methodology is to be achieved, an increased understanding of the damage processes which influence residual strength is required. The study described herein was part of an ongoing investigation of damage development and reduction of tensile strength in filament wound composites subjected to low velocity impacts. The present study, which focused on documenting the damage that develops in filament wound composites as a result of such impacts, included two distinct tasks. The first task was to experimentally assess impact damage in small, filament wound pressure bottles using x-ray radiography. The second task was to study the feasibility of using digital image processing techniques to assist in determining the 3-D distribution of damage from stereo x-ray pairs.

  8. Transient thermal and stress analysis of maxillary second premolar tooth using an exact three-dimensional model.

    PubMed

    Hashemipour, Maryam Alsadat; Mohammadpour, Ali; Nassab, Seiied Abdolreza Gandjalikhan

    2010-01-01

    In this paper, the temperature and stress distributions in an exact 3D-model of a restored maxillary second premolar tooth are obtained with finite element approach. The carious teeth need to restore with appropriate restorative materials. There are too many restorative materials which can be used instead of tooth structures; since tooth structures are being replaced, the restorative materials should be similar to original structure as could as possible. In the present study, a Mesial Occlusal Distal (MOD) type of restoration is chosen and applied to a sound tooth model. Four cases of restoration are investigated: two cases in which base are used under restorative materials and two cases in which base is deleted. The restorative materials are amalgam and composite and glass-inomer is used as a base material. Modeling is done in the solid works ambient by means of an exact measuring of a typical human tooth dimensions. Tooth behavior under thermal load due to consuming hot liquids is analyzed by means of a three dimensional finite element method using ANSYS software. The highest values of tensile and compressive stresses are compared with tensile and compressive strength of the tooth and restorative materials and the value of shear stress on the tooth and restoration junctions is compared with the bond strength. Also, sound tooth under the same thermal load is analyzed and the results are compared with those obtained for restored models. Temperature and stress distributions in the tooth are calculated for each case, with a special consideration in the vicinity of pulp and restoration region. Numerical results show that in two cases with amalgam, using the base material (Glass-ionomer) under the restorative material causes to decrease the maximum temperature in the restorative teeth. In the stress analysis, it is seen that the principal stress has its maximum values in composite restorations. The maximum temperatures are found in the restoration case of amalgam without base. Besides, it is found that restoration has not any influence on the stress values at DEJ, such that for all cases, these values are close to sound tooth results.

  9. Case-Based Instructional Practices: A Multiple-Case Study from Torts, Marketing, and Online Instructional Design Classes

    ERIC Educational Resources Information Center

    Jung, Ji yoon

    2017-01-01

    The purpose of this study is to provide a comprehensive account on case-based instructional practices. Semester-long participant observation records in torts, marketing, and online instructional design classes, instructor interviews, course syllabi and teaching materials were used to describe the within-class complexity of the practices in terms…

  10. 10 CFR 39.39 - Records of material use.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... used; (2) In the case of unsealed licensed material used for subsurface tracer studies, the radionuclide and quantity of activity used in a particular well and the disposition of any unused tracer...

  11. 10 CFR 39.39 - Records of material use.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... used; (2) In the case of unsealed licensed material used for subsurface tracer studies, the radionuclide and quantity of activity used in a particular well and the disposition of any unused tracer...

  12. 10 CFR 39.39 - Records of material use.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... used; (2) In the case of unsealed licensed material used for subsurface tracer studies, the radionuclide and quantity of activity used in a particular well and the disposition of any unused tracer...

  13. 10 CFR 39.39 - Records of material use.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... used; (2) In the case of unsealed licensed material used for subsurface tracer studies, the radionuclide and quantity of activity used in a particular well and the disposition of any unused tracer...

  14. 10 CFR 39.39 - Records of material use.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... used; (2) In the case of unsealed licensed material used for subsurface tracer studies, the radionuclide and quantity of activity used in a particular well and the disposition of any unused tracer...

  15. Corrosion resistance of lithium/iodine batteries fabricated in an extremely dry environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, W.R.; Holmes, C.F.; Stinebring, R.C.

    1981-10-01

    Early lithium/iodine pacemaker batteries employed considerable amounts of inert plastic materials to encase the active ingredients inside the stainless steel case. Several years ago the Wilson Greatbatch Ltd. (WGL) Model 755 cell was introduced and represented a significant change in lithium/iodine battery construction. In this design (1) the iodinepolyvinylpyridine (PVP) depolarizer material was placed in direct contact with the 304L stainless steel case and much of the inert material was eliminated. This change resulted in obtaining substantially more depolarizer in the battery thereby greatly increasing the electrical capacity for the same cell volume. A study was instituted to evaluate possiblemore » corrosion effects between the iodine in the depolarizer and the stainless steel case.« less

  16. As Teachers Tell It: Implementing All Aspects of the Industry. Supporting Materials. [Volume Two.

    ERIC Educational Resources Information Center

    Andrew, Erika Nielsen, Ed.

    This document contains supporting materials from five case studies illustrating the All Aspects of the Industry (AAI) approach. AAI provides a framework for redesigning programs around broadly conceived, interdisciplinary, industry-focused programs and integrating academic and vocational education. Materials from the Boston (Massachusetts) Public…

  17. Training Teachers and Serving Students: Applying Usability Testing in Writing Programs

    ERIC Educational Resources Information Center

    McGovern, Heather

    2007-01-01

    Teachers often test course materials by using them in class. Usability testing provides an alternative: teachers receive student feedback and revise materials "before" teaching a class. Case studies based on interviews and observations with two teaching assistants who usability tested materials before teaching introductory technical writing…

  18. Using Technology and Instructional E-Material among Technical Teacher and Student into Teaching and Learning: A Qualitative Case Study

    ERIC Educational Resources Information Center

    Hashim, Mohamad Hisyam Mohd.

    2015-01-01

    The development of instructional electronic material or e-material for electrical and electronic studies was developed by many companies and institutions. However, the quality of the designed and the potentiality to use as a tool in teaching and learning is still doubtful. For this reason, the aim of this research was to understand the using…

  19. Bringing Fun and Meaning into Grammar Learning: A Case Study of a Secondary-Level EFL Class in Hong Kong

    ERIC Educational Resources Information Center

    Hua, Congchao; Li, Bin

    2015-01-01

    Popular culture materials are generally believed to have positive effects on L2 learning. This study examined the effectiveness of popular culture materials in enhancing Hong Kong EFL students' grammar learning. In a quasi-experimental design, 20 secondary school students were taught grammar in two ways: with the use of popular culture materials,…

  20. Nuclear forensics of a non-traditional sample: Neptunium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doyle, Jamie L.; Schwartz, Daniel; Tandon, Lav

    Recent nuclear forensics cases have focused primarily on plutonium (Pu) and uranium (U) materials. By definition however, nuclear forensics can apply to any diverted nuclear material. This includes neptunium (Np), an internationally safeguarded material like Pu and U, that could offer a nuclear security concern if significant quantities were found outside of regulatory control. This case study couples scanning electron microscopy (SEM) with quantitative analysis using newly developed specialized software, to evaluate a non-traditional nuclear forensic sample of Np. Here, the results of the morphological analyses were compared with another Np sample of known pedigree, as well as other traditionalmore » actinide materials in order to determine potential processing and point-of-origin.« less

  1. Nuclear forensics of a non-traditional sample: Neptunium

    DOE PAGES

    Doyle, Jamie L.; Schwartz, Daniel; Tandon, Lav

    2016-05-16

    Recent nuclear forensics cases have focused primarily on plutonium (Pu) and uranium (U) materials. By definition however, nuclear forensics can apply to any diverted nuclear material. This includes neptunium (Np), an internationally safeguarded material like Pu and U, that could offer a nuclear security concern if significant quantities were found outside of regulatory control. This case study couples scanning electron microscopy (SEM) with quantitative analysis using newly developed specialized software, to evaluate a non-traditional nuclear forensic sample of Np. Here, the results of the morphological analyses were compared with another Np sample of known pedigree, as well as other traditionalmore » actinide materials in order to determine potential processing and point-of-origin.« less

  2. Development of Protocol Materials in Teacher Education: A Case Study in Relating Theory and Practice.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa.

    A protocol materials program was developed to (1) train personnel who produce, use, and make budgetary decisions about protocol materials and (2) produce and disseminate effective materials and knowledge acquired as a result of the program. Two groups were selected to meet the goals of the program--one group consisting of project directors who…

  3. Clinical factors and clinical variation influencing the reproducibility of interocclusal recording methods.

    PubMed

    Eriksson, A; Ockert-Eriksson, G; Lockowandt, P; Eriksson, O

    2002-04-13

    The reproducibility of clinical records of the occlusion was assessed in three dimensions using mounted casts. Three distinct areas were examined: 1) mandibular positions (intercuspal position (IP) or retruded contact position (RCP)), 2) materials used in recording the occlusion, 3) clinical variation. Interocclusal records were made in a random order of three patients: one fixed prosthodontics case, one removable partial denture case and one complete denture case, with two different types of waxes, record rims, two different brands of vinyl polysiloxanes and one irreversible hydrocolloid. Private practice and Karolinska Institute, Huddinge, Sweden. One general dental practitioner and three voluntary patients. Point estimation of variance components indicate that 70-93% of the variation of the positions of the mounted casts are caused by: 1) clinical variation for all three cases and in three directions, 2) the influence of recording materials 0-29%, and 3) mandibular positions (IP/RCP) 0-11%. The ranges of the positions of the mounted casts were lower for the dentate case (0.04-1.39 mm) than for the partially dentate case (0.17-2.65 mm), which in turn was lower than those for the edentulous case (1.42-5.59 mm). Clinical variation seems to dominate the variation in positions of mounting casts when making interocclusal records, rather than mandibular position or the recording materials used. Therefore a dentist who makes one single interocclusal record cannot presume that it will reproduce the interocclusal relationship intended, which in the present study was most obvious for the edentulous case. The results showed that impression materials stabilised by a tray did not differ significantly from waxes and record rims concerning the reproducibility. Therefore the stabilised impression materials are an alternative, which also give additional advantages like reduction of appointments as well as superior accuracy.

  4. The effect of contact lens materials on disinfection activity of polyquaternium-1 and myristamidopropyl dimethylamine multipurpose solution against Staphylococcus aureus.

    PubMed

    Shoff, Megan E; Lucas, Anne D; Phillips, K Scott; Brown, Jennifer N; Hitchins, Victoria M; Eydelman, Malvina B

    2012-11-01

    This study examined the interaction of seven different lens materials with a multipurpose solution (MPS) containing the disinfectants polyquaternium-1 (0.001%) and myristamidopropyl dimethylamine (0.0005%). The objective of this study was to determine whether the different lens materials affect the concentration of a disinfectant in this commercially available MPS and the efficacy of the disinfectant against Staphylococcus aureus. Silicone hydrogel lenses (galyfilcon A, senofilcon A, comfilcon A, enfilcon A, balafilcon A, and lotrafilcon B) and a conventional hydrogel lens (etafilcon A) were soaked in polypropylene lens cases filled with commercially available MPS containing 0.001% polyquaternium-1 and 0.0005% myristamidopropyl dimethylamine for 6, 12, 24, 72, and 168 hours. Empty lens cases were also filled with MPS. After each time point, solutions from cases containing the seven types of lenses and controls were assayed for activity against S. aureus according to International Standards Organization 14729 standard with modifications. Test solutions were analyzed for polyquaternium-1 and myristamidopropyl dimethylamine concentration at each time point. The concentration of polyquaternium-1 and myristamidopropyl dimethylamine remaining in the lens cases was reduced only slightly over time. Storage with the lenses did not adversely affect biocidal efficacy of the solution, and in some cases, it was significantly better (P=0.0029). The efficacy of this polyquaternium-1 and myristamidopropyl dimethylamine MPS to kill S. aureus was not adversely affected by the presence of lens materials soaking in the cases. Thus, current methods for performing solution antimicrobial testing should be reevaluated.

  5. The CASE Project: Evaluation of Case-Based Approaches to Learning and Teaching in Statistics Service Courses

    ERIC Educational Resources Information Center

    Fawcett, Lee

    2017-01-01

    The CASE project (Case-based Approaches to Statistics Education; see www.mas.ncl.ac.uk/~nlf8/innovation) was established to investigate how the use of real-life, discipline-specific case study material in Statistics service courses could improve student engagement, motivation, and confidence. Ultimately, the project aims to promote deep learning…

  6. The Recovery Care and Treatment Center: A Database Design and Development Case

    ERIC Educational Resources Information Center

    Harris, Ranida B.; Vaught, Kara L.

    2008-01-01

    The advantages of active learning methodologies have been suggested and empirically shown by a number of IS educators. Case studies are one such teaching technique that offers students the ability to think analytically, apply material learned, and solve a real-world problem. This paper presents a case study designed to be used in a database design…

  7. Theoretical Considerations for Improving the Pulse Power of a Battery through the Addition of a Second Electrochemically Active Material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Knehr, K. W.; West, Alan C.

    Here, porous electrode theory is used to conduct case studies for when the addition of a second electrochemically active material can improve the pulse-power performance of an electrode. Case studies are conducted for the positive electrode of a sodium metal-halide battery and the graphite negative electrode of a lithium “rocking chair” battery. The replacement of a fraction of the nickel chloride capacity with iron chloride in a sodium metal-halide electrode and the replacement of a fraction of the graphite capacity with carbon black in a lithium-ion negative electrode were both predicted to increase the maximum pulse power by up tomore » 40%. In general, whether or not a second electrochemically active material increases the pulse power depends on the relative importance of ohmic-to-charge transfer resistances within the porous structure, the capacity fraction of the second electrochemically active material, and the kinetic and thermodynamic parameters of the two active materials.« less

  8. Theoretical Considerations for Improving the Pulse Power of a Battery through the Addition of a Second Electrochemically Active Material

    DOE PAGES

    Knehr, K. W.; West, Alan C.

    2016-05-26

    Here, porous electrode theory is used to conduct case studies for when the addition of a second electrochemically active material can improve the pulse-power performance of an electrode. Case studies are conducted for the positive electrode of a sodium metal-halide battery and the graphite negative electrode of a lithium “rocking chair” battery. The replacement of a fraction of the nickel chloride capacity with iron chloride in a sodium metal-halide electrode and the replacement of a fraction of the graphite capacity with carbon black in a lithium-ion negative electrode were both predicted to increase the maximum pulse power by up tomore » 40%. In general, whether or not a second electrochemically active material increases the pulse power depends on the relative importance of ohmic-to-charge transfer resistances within the porous structure, the capacity fraction of the second electrochemically active material, and the kinetic and thermodynamic parameters of the two active materials.« less

  9. Censorship of Sexual Materials: A Selected, Annotated Basic Bibliography.

    ERIC Educational Resources Information Center

    Tedford, Thomas L.

    The 37 references in this annotated bibliography are compiled for researchers of information on the censorship of sexual materials from ancient times to present. The materials include case studies, histories, essays, and opinion pieces about the use and regulation of "obscenity" in literature, pictorial art, radio broadcasting, the mail, film, and…

  10. Educative Curriculum Materials: Uptake, Impact, and Implications for Research and Design

    ERIC Educational Resources Information Center

    Davis, Elizabeth A.; Palincsar, Annemarie Sullivan; Smith, P. Sean; Arias, Anna Maria; Kademian, Sylvie M.

    2017-01-01

    The authors synthesize the findings of a research project to extend what is known about educative curriculum materials, or curriculum materials designed with the intent of supporting teacher learning as well as student learning. Drawing on a three-year program of research, including several close observational case studies and a large-scale…

  11. Mechanical Properties and Failure of Biopolymers: Atomistic Reactions to Macroscale Response

    PubMed Central

    Jung, GangSeob; Qin, Zhao

    2017-01-01

    The behavior of chemical bonding under various mechanical loadings is an intriguing mechanochemical property of biological materials, and the property plays a critical role in determining their deformation and failure mechanisms. Because of their astonishing mechanical properties and roles in constituting the basis of a variety of physiologically relevant materials, biological protein materials have been intensively studied. Understanding the relation between chemical bond networks (structures) and their mechanical properties offers great possibilities to enable new materials design in nanotechnology and new medical treatments for human diseases. Here we focus on how the chemical bonds in biological systems affect mechanical properties and how they change during mechanical deformation and failure. Three representative cases of biomaterials related to the human diseases are discussed in case studies, including: amyloids, intermediate filaments, and collagen, each describing mechanochemical features and how they relate to the pathological conditions at multiple scales. PMID:26108895

  12. Interior surface materials in the home and the development of bronchial obstruction in young children in Oslo, Norway.

    PubMed Central

    Jaakkola, J J; Oie, L; Nafstad, P; Botten, G; Samuelsen, S O; Magnus, P

    1999-01-01

    OBJECTIVES: This study assessed the role of polyvinyl chloride (PVC) plastics and textile materials in the home in the development of bronchial obstruction during the first 2 years of life. METHODS: The study was a matched pair case-control study based on a cohort of 3754 newborns in Oslo in 1992 and 1993 who were followed up for 2 years. The case group consisted of 251 children with bronchial obstruction; the control group was matched one-to-one for date of birth. RESULTS: In conditional logistic regression analysis, the risk of bronchial obstruction was related to the presence of PVC flooring (adjusted odds ratio [OR] = 1.89; 95% confidence interval [CI] = 1.14, 3.14) and textile wall materials (adjusted OR = 1.58; 95% CI = 0.98, 2.54). The reference category was wood or parquet flooring and painted walls and ceiling. Further analysis revealed an exposure-response relationship between the assessed amount of PVC and other plasticizer-containing surface materials and the risk of bronchial obstruction. CONCLUSIONS: This study provides new evidence of the role of PVC and textile wall materials in the development of bronchial obstruction in young children. PMID:9949747

  13. Interior surface materials in the home and the development of bronchial obstruction in young children in Oslo, Norway.

    PubMed

    Jaakkola, J J; Oie, L; Nafstad, P; Botten, G; Samuelsen, S O; Magnus, P

    1999-02-01

    This study assessed the role of polyvinyl chloride (PVC) plastics and textile materials in the home in the development of bronchial obstruction during the first 2 years of life. The study was a matched pair case-control study based on a cohort of 3754 newborns in Oslo in 1992 and 1993 who were followed up for 2 years. The case group consisted of 251 children with bronchial obstruction; the control group was matched one-to-one for date of birth. In conditional logistic regression analysis, the risk of bronchial obstruction was related to the presence of PVC flooring (adjusted odds ratio [OR] = 1.89; 95% confidence interval [CI] = 1.14, 3.14) and textile wall materials (adjusted OR = 1.58; 95% CI = 0.98, 2.54). The reference category was wood or parquet flooring and painted walls and ceiling. Further analysis revealed an exposure-response relationship between the assessed amount of PVC and other plasticizer-containing surface materials and the risk of bronchial obstruction. This study provides new evidence of the role of PVC and textile wall materials in the development of bronchial obstruction in young children.

  14. Academic Computing at Florida A&M University. A Case Study.

    ERIC Educational Resources Information Center

    Hunter, Beverly; Kearsley, Greg

    This case study is one of a series on academic computing at minority institutions which is designed to assist educators at other such institutions in identifying academic computing needs, establishing realistic goals, organizing a staff, and selecting materials. Following a brief description of the purpose and background of the overall study, the…

  15. Teaching Kindergartners Racial Diversity through Multicultural Literature: A Case Study in a Kindergarten Classroom in Korea

    ERIC Educational Resources Information Center

    Kim, So Jung; Wee, Su-Jeong; Lee, Young Mi

    2016-01-01

    Research Findings: This qualitative case study examines Korean kindergartners' literary discussions about racial/cultural diversity during a whole-group read-aloud. Using multiple sources of data, including observations, open-ended interviews, and written materials and children's artifacts, this study found that (a) the children exhibited a biased…

  16. Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin

    In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

  17. Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

    DOE PAGES

    Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin; ...

    2017-07-08

    In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

  18. JOB REDESIGN FOR OLDER WORKERS, TEN CASE STUDIES.

    ERIC Educational Resources Information Center

    MITNICK, EDWARD; ROTHBERG, HERMAN

    AFTER IDENTIFYING FIRMS WHICH HAD USED JOB REDESIGN TO SALVAGE THE SKILL OF OLDER EMPLOYEES, RESEARCH INVESTIGATORS MADE 10 INTENSIVE CASE STUDIES IN FIRMS PRODUCING AIRCRAFT ENGINES, ALUMINUM FRAMING, BUILDING MATERIALS, CARPETS, COMPUTERS, COPPER PIPE FITTINGS, FOOTWEAR, HEAVY IRON PIPE, PRECISION INSTRUMENTS, AND PRINTED NOVELTIES. EACH STUDY…

  19. Gap Analysis of Material Properties Data for Ferritic/Martensitic HT-9 Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Neil R.; Serrano De Caro, Magdalena; Rodriguez, Edward A.

    2012-08-28

    The US Department of Energy (DOE), Office of Nuclear Energy (NE), is supporting the development of an ASME Code Case for adoption of 12Cr-1Mo-VW ferritic/martensitic (F/M) steel, commonly known as HT-9, primarily for use in elevated temperature design of liquid-metal fast reactors (LMFR) and components. In 2011, Los Alamos National Laboratory (LANL) nuclear engineering staff began assisting in the development of a small modular reactor (SMR) design concept, previously known as the Hyperion Module, now called the Gen4 Module. LANL staff immediately proposed HT-9 for the reactor vessel and components, as well as fuel clad and ducting, due to itsmore » superior thermal qualities. Although the ASME material Code Case, for adoption of HT-9 as an approved elevated temperature material for LMFR service, is the ultimate goal of this project, there are several key deliverables that must first be successfully accomplished. The most important key deliverable is the research, accumulation, and documentation of specific material parameters; physical, mechanical, and environmental, which becomes the basis for an ASME Code Case. Time-independent tensile and ductility data and time-dependent creep and creep-rupture behavior are some of the material properties required for a successful ASME Code case. Although this report provides a cursory review of the available data, a much more comprehensive study of open-source data would be necessary. This report serves three purposes: (a) provides a list of already existing material data information that could ultimately be made available to the ASME Code, (b) determines the HT-9 material properties data missing from available sources that would be required and (c) estimates the necessary material testing required to close the gap. Ultimately, the gap analysis demonstrates that certain material properties testing will be required to fulfill the necessary information package for an ASME Code Case.« less

  20. [The study of new soft one-piece PHEMA keratoprosthesis implanted into alkali burned rabbits cornea].

    PubMed

    Bai, Hua; Huang, Yi-fei; Wang, Li-qiang

    2013-10-01

    This study was to evaluate clinical results of two types soft one-piece keratoprosthesis (KPros) made of PHEMA implanted to alkali burned rabbit corneas. Experimental study. Twelve pieces KPros were implanted alkali burned rabbit corneas(type I and II, 6 pieces respectively). The examinations including slit-lamp, fundus photography,B-ultrasound and ultrasound biomicroscopy (UBM) were carried out. All Kpros were stable and no complications happened including conjunctiva flap dehiscence, aqueous leak and infection. IOP were normal by finger touch. B-ultrasound show no retina detachment and UBM show synechia in most animals (10 case). Retroprosthetic membrane happened in type I (3 case) . Visible conjunctiva hyperplasia covering the optical region happened in all KPros. (1) The same material, integrated design, maybe eliminating the material interface problem. (2)Simple surgical skills. (3)IOP measurement is possible because of soft material. (4)KPro I do not need removal of the lens and vitrectomy. The projecting portion of KPro II may reduce the incidence of proliferative membrane. Long term effects need more cases and further observation.

  1. Recovery technologies for building materials

    NASA Astrophysics Data System (ADS)

    Karu, Veiko; Nurme, Martin; Valgma, Ingo

    2015-04-01

    Mining industry provides building materials for construction. Civil engineers have settled the quality parameters for construction materials. When we produce high quality building materials from carbonate rock (limestone, dolostone), then the estimated waste share is 25% to 30%, depending on crushing principles and rock quality. The challenge is to find suitable technology for waste recovery. During international mining waste related cooperation project MIN-NOVATION (www.min-novation.eu), partners mapped possibilities for waste recovery in mining industry and pointed out good examples and case studies. One example from Estonia showed that when we produce limestone aggregate, then we produce up to 30% waste material (fines with size 0-4mm). This waste material we can see as secondary raw material for building materials. Recovery technology for this fine grained material has been achieved with CDE separation plant. During the process the plant washes out minus 63 micron material from the limestone fines. This technology allows us to use 92% of all limestone reserves. By-product from 63 microns to 4 mm we can use as filler in concrete or as fine limestone aggregate for building or building materials. MIN-NOVATION project partners also established four pilot stations to study other mineral waste recovery technologies and solutions. Main aims on this research are to find the technology for recovery of mineral wastes and usage for new by-products from mineral mining waste. Before industrial production, testing period or case studies are needed. This research is part of the study of Sustainable and environmentally acceptable Oil shale mining No. 3.2.0501.11-0025 http://mi.ttu.ee/etp and the project B36 Extraction and processing of rock with selective methods - http://mi.ttu.ee/separation; http://mi.ttu.ee/miningwaste/

  2. [Unstable thorax fixation with bioabsorbable plates and screws. Presentation of some cases].

    PubMed

    Nolasco-de la Rosa, Ana Lilia; Mosiñoz-Montes, Roberto; Matehuala-García, Jesús; Román-Guzmán, Edgardo; Quero-Sandoval, Fidel; Reyes-Miranda, Alma Lorena

    2015-01-01

    Flail chest is managed with mechanical ventilation or inhalation therapy, and analgesia. Mechanical ventilations carry risks by themselves and disengage with the external fixators so they must be operated to improve lung ventilatory mechanics and cleaning. Little has been published on the use of bioabsorbable material and its evolution in the setting of flail chest. A material that did had to be retired, that presented the malleability of titanium and its inflammatory reaction was minimal and could be handled in both adults and children was investigated. Here is shown a descriptive study of patients with flail chest under rib fixation with plates and bioabsorbable screws. 18 cases are presented, aged 33-74 years, three with bilateral flail chest; fixation was performed between days 1-21 of the accident. In cases that showed no fractures pelvic limbs, gait next day restarted fi ng in all cases improved mechanical ventilation, pain decreased, none has so far presented reaction material. Flail chest has a high (16.3%) mortality when no management provides the pathophysiology of the condition (pain, poor mechanical ventilation, alveolar edema-pulmonary contusion). The use of bioabsorbable material has no side effects attributable to material which is another option for rib fixation. Copyright © 2015. Published by Masson Doyma México S.A.

  3. Accuracy of palpation-directed intra-articular glenohumeral injection confirmed by magnetic resonance arthrography.

    PubMed

    Powell, Scott E; Davis, Shane M; Lee, Emily H; Lee, Robert K; Sung, Ryan M; McGroder, Claire; Kouk, Shalen; Lee, Christopher S

    2015-02-01

    The aim of this study was to determine the accuracy of anatomic palpation-directed injections in the office setting. Two hundred twenty-six shoulders in 208 patients were studied using a 0.2-Tesla extremity scanner after the injection of gadolinium-diethylene triamine pentaacetic acid-saline. All patients were injected in a sterile fashion by a single board-certified shoulder surgeon using an anterior approach by palpating the rotator interval anterior to the acromioclavicular joint and angling the needle 45° lateral and 45° caudad. All injections, successful or otherwise, were single injections. Magnetic resonance (MR) arthrograms were retrospectively read by 2 musculoskeletal fellowship-trained, board certified radiologists to determine whether the injection was in the glenohumeral joint. Two hundred one of the 226 injections were successful (88.9%). Of the 25 unsuccessful injections, the contrast material extravasated out of the capsule in 5 cases and into the subscapularis tendon in 10 cases. The contrast material was injected into the subacromial space in 9 cases, into the rotator interval fat in 9 cases, and into extracapsular tissue in 6 cases. There was insufficient volume of contrast material in 10 cases. The accuracy rate was 88.9%. There were no complications. The palpation-directed rotator interval anterior approach technique for intra-articular glenohumeral MR arthrogram injections performed by a single surgeon was 88.9% accurate. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  4. JOB REDESIGN FOR OLDER WORKERS--CASE STUDIES.

    ERIC Educational Resources Information Center

    ROTHBERG, HERMAN J.

    INDUSTRIAL ESTABLISHMENTS SUCCESSFULLY USED METHODS OF JOB REDESIGN TO MAINTAIN THE EMPLOYMENT AND PRODUCTIVITY, AS WELL AS THE MORALE, OF AGING EMPLOYEES. EXAMPLES OF JOB REDESIGN WERE FOUND IN A WIDE VARIETY OF MANUFACTURING INDUSTRIES. CASE STUDIES WERE MADE IN PLANTS PRODUCING AIRCRAFT ENGINES, ALUMINUM FRAMING, BUILDING MATERIALS, CARPETS,…

  5. Case Studies in Applied Mathematics.

    ERIC Educational Resources Information Center

    Mathematical Association of America, Washington, DC.

    This collection of nine case studies in applied mathematics was written primarily for the use of the instructor by a Conference sponsored by the Committee on the Undergraduate Program in Mathematics (CUPM). Each chapter contains exercises of varying degrees of difficulty and several include student projects. The materials were used on a trial…

  6. OER Use in Intermediate Language Instruction: A Case Study

    ERIC Educational Resources Information Center

    Godwin-Jones, Robert

    2017-01-01

    This paper reports on a case study in the experimental use of Open Educational Resources (OERs) in intermediate level language instruction. The resources come from three sources: the instructor, the students, and open content repositories. The objective of this action research project was to provide student-centered learning materials, enhance…

  7. A case study of culturally appropriate conservation education

    Treesearch

    David N. Bengston; Michele Schermann

    2016-01-01

    Create culturally appropriate conservation education materials for Hmong Americans, including new refugees and elders with little proficiency in English, as well as the broader, multigenerational Hmong community. This case study discusses an organizational response from the USDA Forest Service, in partnership with others, to better serve the Hmong American community....

  8. Job and industry classifications associated with sarcoidosis in A Case-Control Etiologic Study of Sarcoidosis (ACCESS).

    PubMed

    Barnard, Juliana; Rose, Cecile; Newman, Lee; Canner, Martha; Martyny, John; McCammon, Chuck; Bresnitz, Eddy; Rossman, Milt; Thompson, Bruce; Rybicki, Benjamin; Weinberger, Steven E; Moller, David R; McLennan, Geoffrey; Hunninghake, Gary; DePalo, Louis; Baughman, Robert P; Iannuzzi, Michael C; Judson, Marc A; Knatterud, Genell L; Teirstein, Alvin S; Yeager, Henry; Johns, Carol J; Rabin, David L; Cherniack, Reuben

    2005-03-01

    To determine whether specific occupations and industries may be associated with sarcoidosis. A Case Control Etiologic Study of Sarcoidosis (ACCESS) obtained occupational and environmental histories on 706 newly diagnosed sarcoidosis cases and matched controls. We used Standard Industrial Classification (SIC) and Standard Occupational Classification (SOC) to assess occupational contributions to sarcoidosis risk. Univariable analysis identified elevated risk of sarcoidosis for workers with industrial organic dust exposures, especially in Caucasian workers. Workers for suppliers of building materials, hardware, and gardening materials were at an increased risk of sarcoidosis as were educators. Work providing childcare was negatively associated with sarcoidosis risk. Jobs with metal dust or metal fume exposures were negatively associated with sarcoidosis risk, especially in Caucasian workers. In this study, we found that exposures in particular occupational settings may contribute to sarcoidosis risk.

  9. Life cycle design metrics for energy generation technologies: Method, data, and case study

    NASA Astrophysics Data System (ADS)

    Cooper, Joyce; Lee, Seung-Jin; Elter, John; Boussu, Jeff; Boman, Sarah

    A method to assist in the rapid preparation of Life Cycle Assessments of emerging energy generation technologies is presented and applied to distributed proton exchange membrane fuel cell systems. The method develops life cycle environmental design metrics and allows variations in hardware materials, transportation scenarios, assembly energy use, operating performance and consumables, and fuels and fuel production scenarios to be modeled and comparisons to competing systems to be made. Data and results are based on publicly available U.S. Life Cycle Assessment data sources and are formulated to allow the environmental impact weighting scheme to be specified. A case study evaluates improvements in efficiency and in materials recycling and compares distributed proton exchange membrane fuel cell systems to other distributed generation options. The results reveal the importance of sensitivity analysis and system efficiency in interpreting case studies.

  10. Virtual and Material Buildings: Construction and Constructivism in Architecture and Writing.

    ERIC Educational Resources Information Center

    Medway, Peter

    1996-01-01

    Endorses recent arguments for more study of writing that shapes and directs the production of material artifacts and for considering writing as one semiotic mode among others. Considers a case of "nonwritten" symbolic production, architectural design, for what it may suggest for the study and teaching of writing. (TB)

  11. Applied Nuclear Accountability Systems: A Case Study in the System Architecture and Development of NuMAC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campbell, Andrea Beth

    2004-07-01

    This is a case study of the NuMAC nuclear accountability system developed at a private fuel fabrication facility. This paper investigates nuclear material accountability and safeguards by researching expert knowledge applied in the system design and development. Presented is a system developed to detect and deter the theft of weapons grade nuclear material. Examined is the system architecture that includes: issues for the design and development of the system; stakeholder issues; how the system was built and evolved; software design, database design, and development tool considerations; security and computing ethics. (author)

  12. Solving real decay and conservation problems of building materials by ultrasounds technique

    NASA Astrophysics Data System (ADS)

    Alvarez de Buergo, Monica; Fort, Rafael; Gomez-Heras, Miguel; Vazquez-Calvo, Carmen

    2010-05-01

    In this study a variety of case studies and different building materials in which ultrasounds velocity played a significant role are shown, either to characterize building materials, to measure deterioration, to assess conservation techniques or for preventive purposes. Regarding to materials properties, ultrasounds velocity provided interesting indices such as the quality index (useful when selecting replacing materials, materials for new constructions or either for sculptures); alteration index (very much related to pores and voids, and fissures); mechanical strength (assessing its reduction when materials are affected by several decay processes, being fire one of them) or anisotropy indices, which highly condition the decay of elements and materials in buildings and sculptures, and which vary themselves with decay progress. The technique is also a tool for detecting and locating elements inside structures, like metallic ones, and also to detect and locate discontinuities inside elements, both for consolidation purposes or even in cases of structures movement, which is quite common nowadays. Using some specific software, ultrasounds results can be plotted as iso-areas, which allows to define areas or zones of structures with the highest risk of detachment in a short-time in order to plan the most adequate interventions. Not new is also the aid of ultrasonics to assess consolidation products and to determine the degree of materials decay when submitted to artificial ageing. Much more innovative is the fact that ultrasonics measurement can be also helpful to determine different building periods in a same building, even the fact of determining an element's lifetime. The results obtained by this non destructive and portable technique that will be presented in this session correspond to both real case studies (results that helped to solve a real problem), some of them corresponding to emblematic monuments de España (Royal Palace of Madrid and some other monuments belonging to the Spanish National Heritage or Trust, archaeological structures and sculptures), and also to laboratory research to understand processes and helpful to see the best way of preservation. In some of the cases, other techniques have been used as complementary, such as sclerommetry, magnetometry and IR termography. Acknowledgements: to both MATERNAS (0505/MAT/0094) and GEOMATERIALES (2009-1629) research programmes, funded by the Regional Government of Madrid; and to the CONSOLIDER-INGENIO programme (CSD2007-0058), funded by the Spanish Ministry of Education and Science.

  13. Material Use in the United States - Selected Case Studies for Cadmium, Cobalt, Lithium, and Nickel in Rechargeable Batteries

    USGS Publications Warehouse

    Wilburn, David R.

    2008-01-01

    This report examines the changes that have taken place in the consumer electronic product sector as they relate to (1) the use of cadmium, cobalt, lithium, and nickel contained in batteries that power camcorders, cameras, cell phones, and portable (laptop) computers and (2) the use of nickel in vehicle batteries for the period 1996 through 2005 and discusses forecasted changes in their use patterns through 2010. Market penetration, material substitution, and technological improvements among nickel-cadmium (NiCd), nickel-metal-hydride (NiMH), and lithium-ion (Li-ion) rechargeable batteries are assessed. Consequences of these changes in light of material consumption factors related to disposal, environmental effects, retail price, and serviceability are analyzed in a series of short case studies.

  14. Teacher-Parent Communication and Parents' Ability to Select Reading Material: A Study of a Baggy Book Program

    ERIC Educational Resources Information Center

    Lorenz, Kelley M.

    2013-01-01

    This study examined the effects of a home-reading program on parent-teacher communication and on the ability of parents to select reading material for their children. In this qualitative case study, parents of 4th grade students participated in a reading homework program with their children. Using constructivist theories, the study's…

  15. Problem Oriented Literacy Materials Preparation: A Case Study

    ERIC Educational Resources Information Center

    Tripathi, Virendra

    1975-01-01

    One of the recent innovations of significance in developing nations is the concept of linking literacy education to problems related to socio-economic development. The article describes the Problem Oriented Materials Preparation Project of Literacy House, Lucknow, India. (Author/BP)

  16. Beneficial Uses of Dredged Material Case Study: San Francisco Bay Region

    EPA Pesticide Factsheets

    A major interagency, regional planning effort led to the development of the Long-Term Management Strategy and other planning programs in the San Francisco Bay area. These programs incorporate beneficial uses of dredged material into local projects.

  17. Understanding materials behavior from atomistic simulations: Case study of al-containing high entropy alloys and thermally grown aluminum oxide

    NASA Astrophysics Data System (ADS)

    Yinkai Lei

    Atomistic simulation refers to a set of simulation methods that model the materials on the atomistic scale. These simulation methods are faster and cheaper alternative approaches to investigate thermodynamics and kinetics of materials compared to experiments. In this dissertation, atomistic simulation methods have been used to study the thermodynamic and kinetic properties of two material systems, i.e. the entropy of Al-containing high entropy alloys (HEAs) and the vacancy migration energy of thermally grown aluminum oxide. (Abstract shortened by ProQuest.).

  18. Implementation of Pedagogical Content Knowledge (PCK) of Mathematics Teachers in Teaching Practice: A Case Study

    ERIC Educational Resources Information Center

    Maryono; Sutawidjaja, Akbar; Subanji; Irawati, Santi

    2017-01-01

    This study aims to describe the implementation of pedagogical content knowledge (PCK) of mathematics teachers in the teaching practice of the material system of linear equations of two variables (SLETV). The approach used is a qualitative case study. The main instrument is the researchers themselves and the supporting instruments is a vignette…

  19. Connecting Reading and Writing: A Case Study

    ERIC Educational Resources Information Center

    Li, Zhanfang

    2015-01-01

    Connecting reading and writing, proposed by many scholars, is realized in this case study. The 30 participants in this study are the English majors of the third year in one School of Foreign Languages in Beijing. They are encouraged to write journals every week, based on the source text materials in their Intensive Reading class, with the final…

  20. Case Studies: Persecution/Genocide. The Human Rights Series. Volume III.

    ERIC Educational Resources Information Center

    Litynsky, Walter; And Others

    A continuation of the study of those factors that lead to persecutions and acts of genocide is presented. As students read the materials included in the case studies, they should be referred to the organizing concepts discussed in "Teaching about the Holocaust and Genocide: Introduction. The Human Rights Series, Volume I." Unit 1 in that…

  1. A City Goes to War: A Case Study of Bridgeport, Connecticut, 1914-1917.

    ERIC Educational Resources Information Center

    Banit, Thomas

    1989-01-01

    Presents a case study used for teaching about World War I. Describes Bridgeport, Connecticut, during the period 1914-17. Includes maps, ethnographic data, and primary materials, such as newspaper accounts and speeches by U.S. President Woodrow Wilson. Provides learning objectives, study questions, and a glossary. Discusses the impact of the war on…

  2. The Use of Instructional Simulations to Support Classroom Teaching: A Crisis Communication Case Study

    ERIC Educational Resources Information Center

    Shifflet, Mark; Brown, Jane

    2006-01-01

    The purpose of this study was to investigate how exposure to classroom instruction affected the use of a computer simulation that was designed to provide students an opportunity to apply material presented in class. The study involved an analysis of a computer-based crisis communication case study designed for a college-level public relations…

  3. Biological materials by design.

    PubMed

    Qin, Zhao; Dimas, Leon; Adler, David; Bratzel, Graham; Buehler, Markus J

    2014-02-19

    In this topical review we discuss recent advances in the use of physical insight into the way biological materials function, to design novel engineered materials 'from scratch', or from the level of fundamental building blocks upwards and by using computational multiscale methods that link chemistry to material function. We present studies that connect advances in multiscale hierarchical material structuring with material synthesis and testing, review case studies of wood and other biological materials, and illustrate how engineered fiber composites and bulk materials are designed, modeled, and then synthesized and tested experimentally. The integration of experiment and simulation in multiscale design opens new avenues to explore the physics of materials from a fundamental perspective, and using complementary strengths from models and empirical techniques. Recent developments in this field illustrate a new paradigm by which complex material functionality is achieved through hierarchical structuring in spite of simple material constituents.

  4. Crime event 3D reconstruction based on incomplete or fragmentary evidence material--case report.

    PubMed

    Maksymowicz, Krzysztof; Tunikowski, Wojciech; Kościuk, Jacek

    2014-09-01

    Using our own experience in 3D analysis, the authors will demonstrate the possibilities of 3D crime scene and event reconstruction in cases where originally collected material evidence is largely insufficient. The necessity to repeat forensic evaluation is often down to the emergence of new facts in the course of case proceedings. Even in cases when a crime scene and its surroundings have undergone partial or complete transformation, with regard to elements significant to the course of the case, or when the scene was not satisfactorily secured, it is still possible to reconstruct it in a 3D environment based on the originally-collected, even incomplete, material evidence. In particular cases when no image of the crime scene is available, its partial or even full reconstruction is still potentially feasible. Credibility of evidence for such reconstruction can still satisfy the evidence requirements in court. Reconstruction of the missing elements of the crime scene is still possible with the use of information obtained from current publicly available databases. In the study, we demonstrate that these can include Google Maps(®*), Google Street View(®*) and available construction and architecture archives. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Study of Super Dielectric Material for Novel Paradigm Capacitors

    DTIC Science & Technology

    2018-03-01

    maximized. Interestingly, CHD protocol did not have a predictable or notable effect on performance in this study . In fact, in several cases shorter...measurement, such as dark matter and dark energy, the same inductive logic approach has been taken for the present study . In this case , we first applied...indicates the constant voltage hold duration. In two cases , a third term ‘No Weight’ indicates that a weight was not placed on top of the glass-capacitor

  6. Seeking instructional specificity: An example from analogical instruction

    NASA Astrophysics Data System (ADS)

    Kuo, Eric; Wieman, Carl E.

    2015-12-01

    Broad instructional methods like "interactive engagement" have been shown to be effective, but such general characterization provides little guidance on the details of how to structure instructional materials. In this study, we seek instructional specificity by comparing two ways of using an analogy to learn a target physical principle: (i) applying the analogy to the target physical domain on a case-by-case basis and (ii) using the analogy to create a general rule in the target physical domain. In the discussion sections of a large, introductory physics course (N =2 3 1 ), students who sought a general rule were better able to discover and apply a correct physics principle than students who analyzed the examples case by case. The difference persisted at a reduced level after subsequent direct instruction. We argue that students who performed case-by-case analyses were more likely to focus on idiosyncratic problem-specific features rather than the deep structural features. This study provides an example of investigations into how the specific structure of instructional materials can be consequential for what is learned.

  7. [Creation and Evaluation of Educational Programs for Additional Delayed Scan of FDG-PET/CT].

    PubMed

    Wada, Ryota; Kamiya, Takashi; Fujino, Kouichi; Ueda, Junpei; Isohashi, Kayako; Tatsumi, Mitsuaki; Hatazawa, Jun

    Generally, FDG-PET/CT image is acquired at the 60th minute after tracer administration. Depending on the clinical case, additional delayed scans may be useful. However, it is difficult to judge whether additional delayed scan is useful or not. The purposes of this study were creation and evaluation of educational programs to help radiological technologists to decide the usefulness of additional delayed scan of FDG-PET/CT. Educational programs consisted of the instructional materials and the judgment test of clinical cases. The instructional materials provided the valuable findings for differentiation between uptake in the wall of the colon and colon content, distinction between uptake in the lymph node and urinary tract, and evaluation of malignancy. The judgment test of clinical cases consisted of 10 cases selected by a nuclear medicine physician (for 5 of that cases additional delayed scan was decided to be useful). Five experienced technologists and five inexperienced technologists scored the volubility of additional delayed scan pre- and post-training using the instructional materials (the full marks of score is 5). After the educational programs using the instructional materials, the score was improved with the significant difference in both experienced (pre: 3.6±1.4, post: 4.0±1.2) and inexperienced (pre: 2.8±1.5, post: 3.7±1.5) groups (p<0.05). According to the educational programs, technologist might be able to decide whether the additional delayed scan is useful or not. The successful results of this study may improve the interpretation or reduce the total exposure dose of the PET/CT scan.

  8. Child Sexual Abuse Confirmed by Forensic Examination in Salvador, Bahia, Brazil.

    PubMed

    Silva, Welington Dos Santos; Barroso-Junior, Ubirajara de Oliveira

    2017-03-01

    Child sexual abuse is a worldwide public health issue. The objective of this study was to describe the demographic and clinical characteristics of children in cases of sexual abuse confirmed by material evidence at forensic examination. Cases of children younger than 12 years examined for suspected sexual abuse at the Institute of Forensic Medicine in Salvador, Bahia, Brazil, were reviewed retrospectively. The period evaluated was between 2005 and 2010. The inclusion criterion was the coroner's confirmation of sexual abuse based on material evidence. The mean age of the children in whom sexual abuse was confirmed was 8.2 (SD, 2.9) years, and 208 cases were female (83.9%). In 94% of the cases, the reason for carrying out the forensic examination was a report of sexual abuse. Less than 1% of the aggressors were female. A ruptured hymen was the finding that confirmed sexual abuse in 172 cases, corresponding to 83% of cases in girls. There were 2 cases of pregnancy. Recent anal or perianal lesions were present in 35 (87.5%) of the confirmed cases involving boys. Laboratory confirmation based on the detection of spermatozoa or prostate-specific antigen occurred in only 4.2% of cases. In all these cases, sample collection was performed within 24 hours of the alleged abuse. Thus, in the majority of cases with material evidence of sexual abuse, the confirmation criteria consisted of a ruptured hymen and recent perianal lesions.

  9. Modelling the Longevity of Dental Restorations by means of a CBR System

    PubMed Central

    Aliaga, Ignacio J.; Vera, Vicente; García, Alvaro E.

    2015-01-01

    The lifespan of dental restorations is limited. Longevity depends on the material used and the different characteristics of the dental piece. However, it is not always the case that the best and longest lasting material is used since patients may prefer different treatments according to how noticeable the material is. Over the last 100 years, the most commonly used material has been silver amalgam, which, while very durable, is somewhat aesthetically displeasing. Our study is based on the collection of data from the charts, notes, and radiographic information of restorative treatments performed by Dr. Vera in 1993, the analysis of the information by computer artificial intelligence to determine the most appropriate restoration, and the monitoring of the evolution of the dental restoration. The data will be treated confidentially according to the Organic Law 15/1999 on 13 December on the Protection of Personal Data. This paper also presents a clustering technique capable of identifying the most significant cases with which to instantiate the case-base. In order to classify the cases, a mixture of experts is used which incorporates a Bayesian network and a multilayer perceptron; the combination of both classifiers is performed with a neural network. PMID:25866792

  10. Adolescent Students' Intercultural Awareness When Using Culture-Based Materials in the English Class (La conciencia intercultural de estudiantes adolescentes al usar materiales con contenido cultural en la clase de inglés)

    ERIC Educational Resources Information Center

    Castañeda Usaquén, Mireya Esther

    2012-01-01

    This article reports on a qualitative and interpretative case study conducted at a high school located in the southeast of Bogotá. The case is comprised of a group of fifty-one eighth graders who had had little contact with English. It aimed at exploring how these adolescents made sense of the culture-based materials implemented in the English…

  11. Hairy carbon electrodes studied by cyclic voltammetry and battery discharge testing

    NASA Technical Reports Server (NTRS)

    Chung, Deborah D. L.; Shui, Xiaoping; Frysz, Christine A.

    1993-01-01

    Hairy carbon is a new material developed by growing submicron carbon filaments on conventional carbon substrates. Typical substrate materials include carbon black, graphite powder, carbon fibers, and glassy carbon. A catalyst is used to initiate hair growth with carbonaceous gases serving as the carbon source. To study the electrochemical behavior of hairy carbons, cyclic voltammetry (CV) and discharge testing were conducted. In both cases, hairy carbon results surpassed those of the substrate material alone.

  12. Juvenile hyaline fibromatosis: a case report and review of literature.

    PubMed

    Ribeiro, Sandra Lúcia; Guedes, Erilane L; Botan, Valeria; Barbosa, Alessandra; Freitas, Ernani J

    2009-01-01

    Juvenile hyaline fibromatosis (JHF) is a rare disease with autosomal recessive inheritance that occurs mainly in childhood and is characterized by the deposition of amorphous hyaline material in the skin and other organs. There are approximately 70 cases reported in the literature. Herein we describe the case of a 14-month-old boy with multiple cutaneous nodules around small and large joints, papulous skin lesions, hyperpigmented plaques and nodules in the perianal region, flexion contractures and stiffness of joints and diffuse osteoporosis. Symptoms were present since the second month of life. Histopathologic studies of joint nodulations demonstrated the presence of hyaline material, confirming the diagnosis of juvenile hyaline fibromatosis.

  13. The Case for Authentic Materials on Videodisc.

    ERIC Educational Resources Information Center

    Saint-Leon, Claire Brandicourt

    1988-01-01

    Foreign language video is invaluable for enhancing foreign language instruction, particularly when combined with laser videodisc technology, which allows learners to study minute details. Authentic materials should be made available on videodisks to fully exploit the resources of foreign language video. (Author/CB)

  14. [Cost analysis of intraoperative neurophysiological monitoring (IOM)].

    PubMed

    Kombos, T; Suess, O; Brock, M

    2002-01-01

    A number of studies demonstrate that a significant reduction of postoperative neurological deficits can be achieved by applying intraoperative neurophysiological monitoring (IOM) methods. A cost analysis of IOM is imperative considering the strained financial situation in the public health services. The calculation model presented here comprises two cost components: material and personnel. The material costs comprise consumer goods and depreciation of capital goods. The computation base was 200 IOM cases per year. Consumer goods were calculated for each IOM procedure respectively. The following constellation served as a basis for calculating personnel costs: (a) a medical technician (salary level BAT Vc) for one hour per case; (b) a resident (BAT IIa) for the entire duration of the measurement, and (c) a senior resident (BAT Ia) only for supervision. An IOM device consisting of an 8-channel preamplifier, an electrical and acoustic stimulator and special software costs 66,467 euros on the average. With an annual depreciation of 20%, the costs are 13,293 euros per year. This amounts to 66.46 euros per case for the capital goods. For reusable materials a sum of 0.75 euro; per case was calculated. Disposable materials were calculate for each procedure respectively. Total costs of 228.02 euro; per case were,s a sum of 0.75 euros per case was calculated. Disposable materials were calculate for each procedure respectively. Total costs of 228.02 euros per case were, calculated for surgery on the peripheral nervous system. They amount to 196.40 euros per case for spinal interventions and to 347.63 euros per case for more complex spinal operations. Operations in the cerebellopontine angle and brain stem cost 376.63 euros and 397.33 euros per case respectively. IOM costs amount to 328.03 euros per case for surgical management of an intracranial aneurysm and to 537.15 euros per case for functional interventions. Expenses run up to 833.63 euros per case for operations near the motor cortex and to 117.65 euros per case for intraoperative speech monitoring. Costs for inpatient medical rehabilitation have increased considerably in recent years. In view of the financial situation, it is necessary to reduce postoperative morbidity and the costs it involves. IOM leads to a reduction of morbidity. The costs for IOM calculated here justify its routine application in view of the legal and socioeconomic consequences of surgery-related neurological deficits.

  15. An Empirical Case Study of a Child Sexual Abuse Prevention Initiative in Georgia

    ERIC Educational Resources Information Center

    Schober, Daniel J.; Fawcett, Stephen B.; Thigpen, Sally; Curtis, Anna; Wright, Renee

    2012-01-01

    Objective: This empirical case study describes Prevent Child Abuse Georgia's effort to prevent child sexual abuse (CSA) by educating communities throughout the state on supporting preventive behaviour. The initiative consisted of three major components: (1) dissemination of CSA prevention messages and materials; (2) a statewide helpline that…

  16. The Design of Effective Case Study-Related Learning Strategies Training.

    ERIC Educational Resources Information Center

    Nuttall, Alice E.

    The development of case study training materials for an experimental research strategy is described, and the effects of such training are discussed. The theoretical foundation for learning strategies training was a social-cognitive/expectancy value model of college learning and teaching. In a posttest-only 2-group design, 54 students in an…

  17. Narrowing the Skills Gap: Workplace Literacy Programs in Canada. Final Report.

    ERIC Educational Resources Information Center

    Ottawa Univ. (Ontario).

    This report documents, in case study format, eight workplace literacy programs in Canada. Introductory materials highlight conclusions and discuss reasons for undertaking the project to document the Canadian experience in basic skills training from the perspective of the employer and employee and program design. Each case study or program profile…

  18. "Gaikokugo" Communication in an Intensive Course Format: Case Study Report and Recommendations.

    ERIC Educational Resources Information Center

    Rausch, Anthony; Altizer, Roger, Jr.; Parry, Andrew

    2000-01-01

    This paper is a pedagogically-oriented case study of a "Gaikokugo" Communication course conducted in an intensive format. After a brief introduction and consideration of the intensive course format, the pedagogical approach guiding the course (together with samples of the materials used in the course provided in the appendix) is…

  19. Fueling a Crisis: Public Argument and the 1988 Yellowstone Fire Debate.

    ERIC Educational Resources Information Center

    Hardy-Short, Dayle; Short, C. Brant

    Debate surrounding the 1988 Yellowstone National Park fires provides material for a case study into the relationship between a crisis and public argument. Studies like this reflect the importance of a recent trend in higher education, namely, the analysis of environmental issues from different academic perspectives. In this case, analysis of…

  20. Methods and Case Studies for Teaching and Learning about Failure and Safety.

    ERIC Educational Resources Information Center

    Bignell, Victor

    1999-01-01

    Discusses methods for analyzing case studies of failures of technological systems. Describes two distance learning courses that compare standard models of failure and success with the actuality of given scenarios. Provides teaching and learning materials and information sources for application to aspects of design, manufacture, inspection, use,…

  1. Two case studies: QuietRock QR-530 drywall panels in new and remediated multifamily construction

    NASA Astrophysics Data System (ADS)

    Tinianov, Brian D.

    2005-09-01

    Reliable acoustical isolation continues to be a high risk element of contemporary multifamily construction. Traditional construction techniques, offering potentially high acoustical performance, exist but may be compromised during typical construction or occupation. This paper presents two case studies using a new class of construction material-drywall panels employing constrained layer damping. QuietRock QR-530 damped gypsum board panels are used in a new construction project and as part of a remediation treatment. In a first study, QR-530 panels were used as a drywall alternative in a 2×6, semistaggered, framed wall separating luxury condominiums. Field evaluation per ASTM E36 revealed a normalized noise isolation class of 56. In a second case study, a single layer of QuietRock was applied directly to an existing single stud assembly in a resort hotel. Before and after testing yielded a change of 14 points, raising the noise isolation class from 36 to 50. This paper reviews the details of the test cases and the underlying physical principals of the subject materials.

  2. Correlating particle hardness with powder compaction performance.

    PubMed

    Cao, Xiaoping; Morganti, Mikayla; Hancock, Bruno C; Masterson, Victoria M

    2010-10-01

    Assessing particle mechanical properties of pharmaceutical materials quickly and with little material can be very important to early stages of pharmaceutical research. In this study, a wide range of pharmaceutical materials were studied using atomic force microscopy (AFM) nanoindentation. A significant amount of particle hardness and elastic modulus data were provided. Moreover, powder compact mechanical properties of these materials were investigated in order to build correlation between the particle hardness and powder compaction performance. It was found that the materials with very low or high particle hardness most likely exhibit poor compaction performance while the materials with medium particle hardness usually have good compaction behavior. Additionally, the results from this study enriched Hiestand's special case concept on particle hardness and powder compaction performance. This study suggests that the use of AFM nanoindentation can help to screen mechanical properties of pharmaceutical materials at early development stages of pharmaceutical research.

  3. Bi-material plane with interface crack for the model of semi-linear material

    NASA Astrophysics Data System (ADS)

    Domanskaya, T. O.; Malkov, V. M.; Malkova, Yu. V.

    2018-05-01

    The singular plane problems of nonlinear elasticity (plane strain and plane stress) are considered for bi-material infinite plane with interface crack. The plane is formed of two half-planes. Mechanical properties of half-planes are described by the model of semi-linear material. Using model of this harmonic material has allowed to apply the theory of complex functions and to obtain exact analytical global solutions of some nonlinear problems. Among them the problem of bi-material plane with the stresses and strains jumps at an interface is considered. As an application of the problem of jumps, the problem of interface crack is solved. The values of nominal (Piola) and Cauchy stresses and displacements are founded. Based on the global solutions the asymptotic expansions are constructed for stresses and displacements in a vicinity of crack tip. As an example the case of a free crack in bi-material plane subjected to constant stresses at infinity is studied. As a special case, the analytical solution of the problem of a crack in a homogeneous plane is obtained from the problem for bi-material plane with interface crack.

  4. Evaluation of Four Different Restorative Materials for Restoration of the Periodontal Condition of Wedge-Shaped Defect: A Comparative Study.

    PubMed

    Ruan, Jian-Yong; Gong, Zheng-Lin; Zhang, Rui-Zhi; Zhang, Zhe; Xu, Ran; Li, Da-Xu; Ren, Le; Tao, Hong

    2017-09-16

    BACKGROUND This study aimed to conduct a clinical evaluation of four restorative materials for restoration of dental wedge-shaped defect (WSD) and their impacts on periodontal tissues. MATERIAL AND METHODS A total of 280 maxillary premolars with dental WSD were selected from 106 patients; the patient cases were divided into eight groups according to different combinations of restorative materials (flowable resin composites, Dyract compomers, glass ionomer cement (GIC), light-curing composite resin), and WSD positions (approaching gingival and subgingival positions). Gingival crevicular fluid (GCF) volume, levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and interleukin-1β (IL-1β) in GCF were analyzed, while probing depth (PD), plaque index (PLI), and sulcus bleeding index (SBI) were also measured. The periodontal conditions of all patients were followed prior to restoration, as well as six months and 12 months after restoration. RESULTS After six months of restoration, the overall clinical success rates of flowable resin composites, Dyract compomers, and light-curing composite resin were greater than those of GIC. GCF volume, GCF-AST, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. After 12 months of restoration, the overall clinical success rates of flowable resin composites and Dyract compomers were greater than those of light-curing composite resin and GIC. GCF volume, GCF-AST, GCF-ALP, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. CONCLUSIONS Our study provided evidence that the clinical efficacy of flowable resin composites, Dyract compomers, and light-curing composite resin was greater than that of GIC for restoration of dental WSD.

  5. Evaluation of Four Different Restorative Materials for Restoration of the Periodontal Condition of Wedge-Shaped Defect: A Comparative Study

    PubMed Central

    Ruan, Jian-Yong; Gong, Zheng-Lin; Zhang, Rui-Zhi; Zhang, Zhe; Xu, Ran; Li, Da-Xu; Ren, Le; Tao, Hong

    2017-01-01

    Background This study aimed to conduct a clinical evaluation of four restorative materials for restoration of dental wedge-shaped defect (WSD) and their impacts on periodontal tissues. Material/Methods A total of 280 maxillary premolars with dental WSD were selected from 106 patients; the patient cases were divided into eight groups according to different combinations of restorative materials (flowable resin composites, Dyract compomers, glass ionomer cement (GIC), light-curing composite resin), and WSD positions (approaching gingival and subgingival positions). Gingival crevicular fluid (GCF) volume, levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and interleukin-1β (IL-1β) in GCF were analyzed, while probing depth (PD), plaque index (PLI), and sulcus bleeding index (SBI) were also measured. The periodontal conditions of all patients were followed prior to restoration, as well as six months and 12 months after restoration. Results After six months of restoration, the overall clinical success rates of flowable resin composites, Dyract compomers, and light-curing composite resin were greater than those of GIC. GCF volume, GCF-AST, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. After 12 months of restoration, the overall clinical success rates of flowable resin composites and Dyract compomers were greater than those of light-curing composite resin and GIC. GCF volume, GCF-AST, GCF-ALP, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. Conclusions Our study provided evidence that the clinical efficacy of flowable resin composites, Dyract compomers, and light-curing composite resin was greater than that of GIC for restoration of dental WSD. PMID:28917087

  6. An Examination of Language Teachers' Enactment of Curriculum Materials in the Context of a Centralised Curriculum

    ERIC Educational Resources Information Center

    Li, Zhan; Harfitt, Gary James

    2017-01-01

    This paper examines a ubiquitous yet under-studied area of language pedagogy, namely materials usage. It explores teachers' enactment of curriculum materials by focusing on English language education (ELE) teachers' use of prescribed textbooks to plan and deliver lessons at the tertiary level in Mainland China. A qualitative multi-case study…

  7. Design and Testing of Braided Composite Fan Case Materials and Components

    NASA Technical Reports Server (NTRS)

    Roberts, Gary D.; Pereira, J. Michael; Braley, Michael S.; Arnold, William a.; Dorer, James D.; Watson, William R/.

    2009-01-01

    Triaxial braid composite materials are beginning to be used in fan cases for commercial gas turbine engines. The primary benefit for the use of composite materials is reduced weight and the associated reduction in fuel consumption. However, there are also cost benefits in some applications. This paper presents a description of the braided composite materials and discusses aspects of the braiding process that can be utilized for efficient fabrication of composite cases. The paper also presents an approach that was developed for evaluating the braided composite materials and composite fan cases in a ballistic impact laboratory. Impact of composite panels with a soft projectile is used for materials evaluation. Impact of composite fan cases with fan blades or blade-like projectiles is used to evaluate containment capability. A post-impact structural load test is used to evaluate the capability of the impacted fan case to survive dynamic loads during engine spool down. Validation of these new test methods is demonstrated by comparison with results of engine blade-out tests.

  8. Selected Parametric Effects on Materials Flammability Limits

    NASA Technical Reports Server (NTRS)

    Hirsch, David B.; Juarez, Alfredo; Peyton, Gary J.; Harper, Susana A.; Olson, Sandra L.

    2011-01-01

    NASA-STD-(I)-6001B Test 1 is currently used to evaluate the flammability of materials intended for use in habitable environments of U.S. spacecraft. The method is a pass/fail upward flame propagation test conducted in the worst case configuration, which is defined as a combination of a material s thickness, test pressure, oxygen concentration, and temperature that make the material most flammable. Although simple parametric effects may be intuitive (such as increasing oxygen concentrations resulting in increased flammability), combinations of multi-parameter effects could be more complex. In addition, there are a variety of material configurations used in spacecraft. Such configurations could include, for example, exposed free edges where fire propagation may be different when compared to configurations commonly employed in standard testing. Studies involving combined oxygen concentration, pressure, and temperature on flammability limits have been conducted and are summarized in this paper. Additional effects on flammability limits of a material s thickness, mode of ignition, burn-length criteria, and exposed edges are presented. The information obtained will allow proper selection of ground flammability test conditions, support further studies comparing flammability in 1-g with microgravity and reduced gravity environments, and contribute to persuasive scientific cases for rigorous space system fire risk assessments.

  9. A family health case study. Stillbirth.

    PubMed

    Edmands, E M

    1982-01-01

    This is an example of a case study written to describe the physical and psychological impact of stillbirth on the patient and the family, and how it can be used in the teaching of family health. It is suggested that the teacher prepare the students by reviewing the known causes of stillbirth and the physiology of labor and delivery. The patient, her family, and her community are described in detail. The situation and events are given in the form of a story. After the presentation, questions are put to the students that require their assessment of the requirements of the patient and her family in terms of nursing-midwifery management. A number of follow-ups are suggested for the teacher and students. This material was prepared by INTRAH staff members. Other materials prepared include training exercise in group dynamics, how to use tracing techniques to create visual aids, how to evaluate teaching and how to create a family health case study.

  10. A training tool on how to create a family health case study. Creating a family health case study.

    PubMed

    Naimoli, J; Edmands, E M

    1982-01-01

    1 way of teaching family health is through a case study, which can focus on common situations that occur during the family life cycle. Case studies can also be used to teach students about factors to consider in uncommon situations, or can be designed from the trainer's own experience for a specific group of health workers to make them aware of local customs, beliefs, and practices. The general guidelines are the following: 1) determine specifice objectives; 2) outline the content to be covered; 3) develop the case study; 4) test and revise it. In developing the study it is useful to focus on 1 member in a community, providing information about social, physical, and personal history. Make a point of telling a story, and select a format that is suitable for one's purposes. It is important to obtain the reaction and critique of more than 1 colleague and to evaluate the study after it has been presented to students. There should be enough information to stimulate the students' thinking and to give them something to work with, and, at the same time, certain data should be omitted so that they can identify what is missing and needed. The material was prepared by INTRAH staff members. Other materials include training in group dynamics, how to use tracing techniques to create visual aids, and how to evaluate teaching. A case study on stillbirth is presented in an adjacent article.

  11. In-vivo assessment of barbed suturing thread with regard to tissue reaction and material absorption in a rat model.

    PubMed

    Petrut, Bogdan; Hogea, Maximiliam; Fetica, Bogdan; Kozan, Andrei; Feflea, Dragos; Sererman, Gabriel; Goezen, Ali Serdar; Rassweiler, Jens

    2013-01-01

    The laparoscopic approach in urological surgery demands a high degree of skill in intracorporeal suturing and knot tying. In an effort to reduce the amount of time required to perform a suture, new materials have been developed that through selfanchorage distribute tension more evenly across the suture and also eliminate the need of knot tying. The goal of this study was to assess the in vivo tissue response to a novel material (V-Loc tm; Covidien) in comparison to established materials (Vicryl, PDS II), in the case of bladder suturing, in a rat model. The study included 48 male Wistar rats. All underwent a median abdominal incision, with a 1cm cystotomy, followed by a running suture. The suture material used was either V-Loc absorbable self anchoring thread, Vicryl threaded absorbable suture or monofilament absorbable suture. The abdominal cavity and the bladder suture were macroscopically evaluated at the rats' scheduled death at 3 and 6 weeks. The bladder wall was microscopically assessed by a pathologist, with regard to tissue reaction and suture material degradation. All rats survived the procedure, with the abdominal scar fully healed at week 2. There were no signs of infection or lithiasis during the observation. Macroscopically, at 3 weeks, the suture material was recognizable and visible in all cases, with special mention that the V-Loc thread was considerably more rigid, retaining its shape almost entirely, and provoked more adhesion of the surrounding tissue. At 6 weeks, the suture was indistinguishable in the bladder wall in the case of monofilament absorbable material, barely visible in the case of Vicryl, while the aspect of the V-Loc suture resembled the one at 3 weeks, with the material still clearly visible in the bladder wall, shape almost entirely maintained, and surrounding tissue adherence. Microscopically, at 3 weeks and 6 weeks, all bladder walls examined had regained their structure. At 3 weeks, the monofilament absorbable suture showed intense tissue reaction, with the material already in phagocytosis; at 6 weeks, no clear evidence of leftover material was observed. At 3 weeks, the Vicryl material showed moderate tissue reaction, with phagocytosis initiated between the strands of the material; at 6 weeks, the material was almost entirely absorbed, but with a clear leftover tissue reaction. In the case of the V-Loc suture, due to the hardness of the thread, the material itself could not be cut for analysis with the bladder wall, and the examination could only involve the bladder wall and marks of the thread. Thus, the tissue reaction was minimal, as was the presence of phagocytes at the suture site. The material showed little, if any, signs of absorption after 6 weeks. The materials tested all proved equally effective in suturing the bladder wall in a rat model. However, the novel barbed thread proved a consistently low in-vivo absorption rate, while maintaining its rigidity over time. More research is needed to assess the possible clinical implications of these findings.

  12. In-vivo assessment of barbed suturing thread with regard to tissue reaction and material absorption in a rat model

    PubMed Central

    PETRUT, BOGDAN; HOGEA, MAXIMILIAM; FETICA, BOGDAN; KOZAN, ANDREI; FEFLEA, DRAGOS; SERERMAN, GABRIEL; GOEZEN, ALI SERDAR; RASSWEILER, JENS

    2013-01-01

    Aim The laparoscopic approach in urological surgery demands a high degree of skill in intracorporeal suturing and knot tying. In an effort to reduce the amount of time required to perform a suture, new materials have been developed that through selfanchorage distribute tension more evenly across the suture and also eliminate the need of knot tying. The goal of this study was to assess the in vivo tissue response to a novel material (V-Loc tm; Covidien) in comparison to established materials (Vicryl, PDS II), in the case of bladder suturing, in a rat model. Methods The study included 48 male Wistar rats. All underwent a median abdominal incision, with a 1cm cystotomy, followed by a running suture. The suture material used was either V-Loc absorbable self anchoring thread, Vicryl threaded absorbable suture or monofilament absorbable suture. The abdominal cavity and the bladder suture were macroscopically evaluated at the rats’ scheduled death at 3 and 6 weeks. The bladder wall was microscopically assessed by a pathologist, with regard to tissue reaction and suture material degradation. Results All rats survived the procedure, with the abdominal scar fully healed at week 2. There were no signs of infection or lithiasis during the observation. Macroscopically, at 3 weeks, the suture material was recognizable and visible in all cases, with special mention that the V-Loc thread was considerably more rigid, retaining its shape almost entirely, and provoked more adhesion of the surrounding tissue. At 6 weeks, the suture was indistinguishable in the bladder wall in the case of monofilament absorbable material, barely visible in the case of Vicryl, while the aspect of the V-Loc suture resembled the one at 3 weeks, with the material still clearly visible in the bladder wall, shape almost entirely maintained, and surrounding tissue adherence. Microscopically, at 3 weeks and 6 weeks, all bladder walls examined had regained their structure. At 3 weeks, the monofilament absorbable suture showed intense tissue reaction, with the material already in phagocytosis; at 6 weeks, no clear evidence of leftover material was observed. At 3 weeks, the Vicryl material showed moderate tissue reaction, with phagocytosis initiated between the strands of the material; at 6 weeks, the material was almost entirely absorbed, but with a clear leftover tissue reaction. In the case of the V-Loc suture, due to the hardness of the thread, the material itself could not be cut for analysis with the bladder wall, and the examination could only involve the bladder wall and marks of the thread. Thus, the tissue reaction was minimal, as was the presence of phagocytes at the suture site. The material showed little, if any, signs of absorption after 6 weeks. Conclusion The materials tested all proved equally effective in suturing the bladder wall in a rat model. However, the novel barbed thread proved a consistently low in-vivo absorption rate, while maintaining its rigidity over time. More research is needed to assess the possible clinical implications of these findings. PMID:26527981

  13. High School Students' Written Argumentation Qualities with Problem-Based Computer-Aided Material (PBCAM) Designed about Human Endocrine System

    ERIC Educational Resources Information Center

    Vekli, Gülsah Sezen; Çimer, Atilla

    2017-01-01

    This study investigated development of students' scientific argumentation levels in the applications made with Problem-Based Computer-Aided Material (PBCAM) designed about Human Endocrine System. The case study method was used: The study group was formed of 43 students in the 11th grade of the science high school in Rize. Human Endocrine System…

  14. Illicit Trafficking of Natural Radionuclides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva

    2008-08-07

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from anmore » operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.« less

  15. Illicit Trafficking of Natural Radionuclides

    NASA Astrophysics Data System (ADS)

    Friedrich, Steinhäusler; Lyudmila, Zaitseva

    2008-08-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  16. Limit analysis, rammed earth material and Casagrande test

    NASA Astrophysics Data System (ADS)

    El-Nabouch, Ranime; Pastor, Joseph; Bui, Quoc-Bao; Plé, Olivier

    2018-02-01

    The present paper is concerned with the simulation of the Casagrande test carried out on a rammed earth material for wall-type structures in the framework of Limit Analysis (LA). In a preliminary study, the material is considered as a homogeneous Coulomb material, and existing LA static and kinematic codes are used for the simulation of the test. In each loading case, static and kinematic bounds coincide; the corresponding exact solution is a two-rigid-block mechanism together with a quasi-constant stress vector and a velocity jump also constant along the interface, for the three loading cases. In a second study, to take into account the influence of compressive loadings related to the porosity of the material, an elliptic criterion (denoted Cohesive Cam-Clay, CCC) is defined based on recent homogenization results about the hollow sphere model for porous Coulomb materials. Finally, original finite element formulations of the static and mixed kinematic methods for the CCC material are developed and applied to the Casagrande test. The results are the same than above, except that this time the velocity jump depends on the compressive loading, which is more realistic but not satisfying fully the experimental observations. Therefore, the possible extensions of this work towards non-standard direct methods are analyzed in the conclusion section.

  17. Forensic investigation of plutonium metal: a case study of CRM 126

    DOE PAGES

    Byerly, Benjamin L.; Stanley, Floyd; Spencer, Khal; ...

    2016-11-01

    In our study, a certified plutonium metal reference material (CRM 126) with a known production history is examined using analytical methods that are commonly employed in nuclear forensics for provenancing and attribution. Moreover, the measured plutonium isotopic composition and actinide assay are consistent with values reported on the reference material certificate. Model ages from U/Pu and Am/Pu chronometers agree with the documented production timeline. Finally, these results confirm the utility of these analytical methods and highlight the importance of a holistic approach for forensic study of unknown materials.

  18. Strengthening materials specifications

    NASA Astrophysics Data System (ADS)

    Sampath, K.

    2005-10-01

    Continuing efforts to strengthen materials specifications readily recognize that a mere compliance with a materials specification only assures a material meeting or exceeding the minimum expectations explicitly detailed in the specification. Implicitly, such efforts also recognize that additional and specific client needs must be addressed as supplementary requirements and introduced during material procurement to reduce risks and assure enhanced performance. This article describes two U.S. Navy-related case studies that allowed further strengthening of the materials specification process, using newer methods and renewed understanding. The first case demonstrates the use of a constraints-based modeling approach to specify the chemical composition of high-performance welding electrodes for critical U.S. Navy applications. This approach helps to distinguish high-performance welding electrode chemical compositions from rich and lean welding electrode chemical compositions that might limit the operational envelope, reduce performance, or both, while increasing overall cost of fabrication but otherwise meet electrode specification requirements. The second case identifies that the size of an ingot could be an important factor while specifying the aluminum and sulfur contents of very large-size, heavy-gauge plates. Renewed understanding of melt fluidity issues associated with the solidification of very large-size ingots shows that deficiencies in through-thickness ductility of heavy-gauge plates are related to controlling aluminum and sulfur contents of the voluminous melt, notwithstanding explicit compliance with specification requirements.

  19. Toward instructional design principles: Inducing Faraday's law with contrasting cases

    NASA Astrophysics Data System (ADS)

    Kuo, Eric; Wieman, Carl E.

    2016-06-01

    Although physics education research (PER) has improved instructional practices, there are not agreed upon principles for designing effective instructional materials. Here, we illustrate how close comparison of instructional materials could support the development of such principles. Specifically, in discussion sections of a large, introductory physics course, a pair of studies compare two instructional strategies for teaching a physics concept: having students (i) explain a set of contrasting cases or (ii) apply and build on previously learned concepts. We compare these strategies for the teaching of Faraday's law, showing that explaining a set of related contrasting cases not only improves student performance on Faraday's law questions over building on a previously learned concept (i.e., Lorentz force), but also prepares students to better learn subsequent topics, such as Lenz's law. These differences persist to the final exam. We argue that early exposure to contrasting cases better focuses student attention on a key feature related to both concepts: change in magnetic flux. Importantly, the benefits of contrasting cases for both learning and enjoyment are enhanced for students who did not first attend a Faraday's law lecture, consistent with previous research suggesting that being told a solution can circumvent the benefits of its discovery. These studies illustrate an experimental approach for understanding how the structure of activities affects learning and performance outcomes, a first step toward design principles for effective instructional materials.

  20. Effect of the ultrasound-assisted preliminary maceration on the efficiency of the essential oil distillation from selected herbal raw materials.

    PubMed

    Kowalski, Radosław; Kowalska, Grażyna; Jamroz, Jerzy; Nawrocka, Agnieszka; Metyk, Damian

    2015-05-01

    The objective of the study was the estimation of the ultrasound-assisted preliminary maceration effect on the efficiency of essential oil distillation and on its qualitative and quantitative composition. The experiment included analyses on three herbal materials, i.e. peppermint leaves (Mentha piperita L.), marjoram herb (Origanum majorana L.), and chamomile flowers (Chamomilla recutita (L.) Rauschert). The study showed that the application of preliminary water maceration of raw material, augmented with ultrasounds, had a statistically significant increasing effect on the amount of oil distilled, in the case of mint leaf from 1.32% to 1.46% v/w, and in the case of marjoram herb from 1.13% to 1.27% v/w. In the case of chamomile flowers no significant effect of ultrasound on the amount of oil obtained was observed. Generally, comparing the composition of essential oils obtained in the experiments with the requirements of the relevant standards no unfavourable effect of the distillation augmenting techniques applied was noted. Therefore, it should be expected that the studied distillates of volatile fractions will have the desired biological activity. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Process feasibility study in support of silicon material task 1

    NASA Technical Reports Server (NTRS)

    Fang, C. S.; Hansen, K. C.; Miller, J. W., Jr.; Yaws, C. L.

    1978-01-01

    Initial results for gas thermal conductivity of silicon tetrafluoride and trichlorosilane are reported in respective temperature ranges of 25 to 400 C and 50 to 400 C. For chemical engineering analyses, the preliminary process design for the original silane process of Union Carbide was completed for Cases A and B, Regular and Minimum Process Storage. Included are raw material usage, utility requirements, major process equipment lists, and production labor requirements. Because of the large differences in surge tankage between major unit operations the fixed capital investment varied from $19,094,000 to $11,138,000 for Cases A and B, respectively. For the silane process the original flowsheet was revised for a more optimum arrangement of major equipment, raw materials and operating conditions. The initial issue of the revised flowsheet (Case C) for the silane process indicated favorable cost benefits over the original scheme.

  2. Case studies in conservation science

    NASA Astrophysics Data System (ADS)

    Bisulca, Christina

    The research presented in this dissertation covers three separate topics of conservation as defined by the National Science Foundation: 1) Materials Stabilization, Strengthening, Monitoring, and Repair; 2. Understanding Material Degradation and Aging; and 3) Materials and Structural Characterization of Cultural Heritage Objects (the 'technical study'). The first topic is addressed through a study to assess the consolidant tetraethoxysilane for the stabilization of alum treated wood. Falling under materials degradation studies is a study published in American Museum Novitates to understand how environmental conditions affect the aging of fossil resins from five different deposits. Two separate studies are included in technical study of cultural heritage objects which comprises the third research area of materials characterization. The first is a survey of red dyes used in Chinese paintings from the Ming Dynasty to the Early Republic (1364-1911). The second is a study of the pigments, dyes and binders used in Hawaiian barkcloth (kapa) from the 19th century.

  3. Qualitative assessment of study materials and communication strategies used in studies that include DNA collection.

    PubMed

    Jenkins, Mary M; Reed-Gross, Erika; Barfield, Wanda D; Prue, Christine E; Gallagher, Margaret L; Rasmussen, Sonja A; Honein, Margaret A

    2011-11-01

    To understand motivations and barriers to participation in studies that include DNA collection, focus group discussions were held with mothers who had participated in a case-control study of birth defects. Recruited mothers had completed an interview and had received a mailed kit containing cytobrushes to collect buccal cells for DNA from herself, her infant, and her infant's father. Six moderator-led focus groups were attended by a total of 38 women residing in Atlanta, Georgia. Focus groups were segmented by DNA collection status (biologics participants or nonparticipants), infant case-control status, infant birthweight, and maternal race and ethnicity. This report assesses maternal attitudes toward study materials and communication strategies. Across groups, respondents expressed concern about how their contact information was obtained. Study materials were described as clear and professional by most women, although some respondents reported confusion about disclosure of individual genetic results. Respondents generally reported that monetary incentives were not a motivation to participate, but increased perceived study legitimacy. Biologics nonparticipants expressed concerns about kit component sterility; government involvement; and DNA sample use, storage, and disposal. Respondents suggested that investigators provide feedback on whether sample collection was performed correctly and provide materials targeted to fathers to help alleviate paternal skepticism. Participation in DNA collection might be improved by strengthening study materials and communication strategies. Published 2011 Wiley Periodicals, Inc. This article is a U.S. Government work and is in the public domain in the USA.

  4. Materials for interocclusal records and their ability to reproduce a 3-dimensional jaw relationship.

    PubMed

    Ockert-Eriksson, G; Eriksson, A; Lockowandt, P; Eriksson, O

    2000-01-01

    The purpose of this study was to determine if accuracy and dimensional stability of vinyl polysiloxanes and irreversible hydrocolloids stabilized by a tray used for fixed prosthodontics, removable partial, and complete denture cases are comparable to those of waxes and record rims and if storage time (24 hours or 6 days) affects dimensional stability of the tested materials. Two waxes, two record rims, three vinyl polysiloxanes, and one irreversible hydrocolloid (alginate) were examined. Three pairs of master casts with measuring steel rods were mounted on an articulator (initial position). Five records were made of each material, and the upper cast was remounted after 24 hours or 6 days so that deviations from the initial position could be measured. Vinyl polysiloxanes reinforced by a stabilization tray were the most accurate materials able to reproduce a settled interocclusal position. Mounting casts (fixed prosthodontics cases) without records gave accuracy similar to wax records. Record rims used for removable partial and complete denture cases produced lesser accuracy than vinyl polysiloxanes and irreversible hydrocolloid stabilized by a tray. Accuracy was not significantly affected by storage time. The results show that accuracy of vinyl polysiloxanes and irreversible hydrocolloids reinforced by a tray is superior to that of record rims with regard to the complete denture case and is among the most accurate with regard to the removable partial denture case. For fixed prosthodontics, however, reinforcement is unnecessary.

  5. Sinks as integrative elements of the anthropogenic metabolism

    NASA Astrophysics Data System (ADS)

    Kral, Ulrich; Brunner, Paul H.

    2015-04-01

    The anthropogenic metabolism is an open system requiring exchange of materials and energy between the anthroposphere and the environment. Material and energy flows are taken from nature and become utilized by men. After utilization, the materials either remain in the anthroposphere as recycling products, or they leave the anthroposphere as waste and emission flows. To accommodate these materials without jeopardizing human and environmental health, limited natural sinks are available; thus, man-made sinks have to be provided where natural sinks are missing or overloaded. The oral presentation (1) suggests a coherent definition of the term "sink", encompassing natural and man-made processes, (2) presents a framework to analyse and evaluate anthropogenic material flows to sinks, based on the tool substance flow analysis and impact assessment methodology, and (3) applies the framework in a case study approach for selected substances such as Copper and Lead in Vienna and Perfluorooctane sulfonate in Switzerland. Finally, the numeric results are aggregated in terms of a new indicator that specifies on a regional scale which fractions of anthropogenic material flows to sinks are acceptable. The following results are obtained: In Vienna, 99% of Cu flows to natural and man-made sinks are in accordance with accepted standards. However, the 0.7% of Cu entering urban soils and the 0.3% entering receiving waters surpass the acceptable level. In the case of Pb, 92% of all flows into sinks prove to be acceptable, but 8% are disposed of in local landfills with limited capacity. For PFOS, 96% of all flows into sinks are acceptable. 4% cannot be evaluated due to a lack of normative criteria, despite posing a risk for human health and the environment. The case studies corroborate the need and constraints of sinks to accommodate inevitable anthropogenic material flows.

  6. Microstructure-property relationships and constitutive response of plastically graded case hardened steels

    NASA Astrophysics Data System (ADS)

    Klecka, Michael A.

    Case hardened materials, popularly used in many demanding engineering applications such as bearings, gears, and wear/impact surfaces, have high surface hardness and a gradient in material properties (hardness, yield strength, etc.) as a function of depth; therefore, they behave as plastically graded materials. In the current study, two different commercially available case carburized steels along with two through hardened steels are characterized to obtain relationships among the volume fraction of subsurface carbides, indentation hardness, elastic modulus, and yield strength as a function of depth. A variety of methods including microindentation, nanoindentation, ultrasonic measurements, compression testing, rule of mixtures, and upper and lower bound models are used to determine the relationships for elastic modulus and compare the experimental results with model predictions. In addition, the morphology, composition, and properties of the carbide particles are also determined. The gradient in hardness with depth in graded materials is commonly determined using microindentation on the cross-section of the material which contains the gradation in microstructure or composition. In the current study, a novel method is proposed to predict the hardness gradient profile using solely surface indentations at a range of loads. The method does not require the graded material to be sectioned, and has practical utility in the surface heat-treatment industry. For a material with a decreasing gradient in hardness, higher indent loads result in a lower measured hardness due to the influence of the softer subsurface layers. A power-law model is presented which relates the measured surface indentation hardness under increasing load to the subsurface gradient in hardness. A coordinated experimental and numerical study is presented to extract the constitutive response of graded materials, utilizing relationships between hardness, plastic deformation, and strain hardening response. The average plastic strain induced by an indent is shown to be an effective measure of the representative plastic strain, which is used in order to relate hardness to yield strength in both virgin and plastically deformed materials. It is shown that the two carburized steels contain gradients in yield strength, but constant strain hardening exponent with depth. The resulting model of material behavior is used to characterize the influence of specific gradients in material properties on the surface indentation behavior under increasing indentation loads. It is also shown that the response of the material is not greatly influenced by strain hardening exponent, while a gradient in strain hardening ability only has minimal impact. Gradients in elastic properties are also shown to have negligible influence for a fixed gradient in hardness. The depth of subsurface plastic deformation is shown to increase with sharper gradients in hardness, but is not altered by gradients in elastic properties. The proposed approach is not specific to case hardened materials and can be used to determine the subsurface hardness gradient for any graded material.

  7. American Civilization in Historic Perspective, Part I. A Guide for Teaching Social Studies, Grade 11.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    This teaching guide offers illustrative and reference materials that are both narrative and graphic on the three topics of Mass Media, Conflicting Ideologies, and Social Control. The objective is to furnish primary materials on these topics not easily available to teachers. Emphasis is on organizing the selections as short cases or studies.…

  8. Using Facebook to Enhance Independent Student Engagement: A Case Study of First-Year Undergraduates

    ERIC Educational Resources Information Center

    Clements, Jeff C.

    2015-01-01

    A case study was conducted to assess the efficacy of online communication tools for enhancing independent student engagement in a first-year undergraduate class. Material relevant to course topics was shared with students through three communication platforms and data were extracted to measure student engagement. A questionnaire was also used to…

  9. Evaluating the Impact of Open Educational Resources: A Case Study

    ERIC Educational Resources Information Center

    Choi, Young Mi; Carpenter, Cathy

    2017-01-01

    This paper presents a case study of the replacement of a textbook with free to use materials in a class on Human Factors and Ergonomics. Data on exam grades, course grades, and student opinions over a total of five semesters are reported, before and after the implementation. The results show that class performance remained similar before and…

  10. Making the Instructional Curriculum as an Interactive, Contextualized Process: Case Studies of Seven ESOL Teachers

    ERIC Educational Resources Information Center

    Wette, Rosemary

    2009-01-01

    This article reports on data from interpretive case studies of seven well-qualified, experienced teachers of adult ESOL, collected through weekly interviews and analysis of documents and materials produced over the duration of a whole course for each teacher. Teachers' knowledge and experience was apparent in their ability to conceptualize and…

  11. Reviving a Community's Adult Education Past: A Case Study of the Library's Role in Learning

    ERIC Educational Resources Information Center

    Irving, Catherine J.

    2010-01-01

    Amidst calls for libraries to regain their socially progressive roots and connections to community, this study analyzes two interwoven cases of nonformal, community education in northeastern Nova Scotia, initiated by libraries that aimed to revive those links. Through a reading circle and a people's school, librarians used historical materials on…

  12. From source material to news story in New Zealand print media: a prospective study of the stigmatizing processes in depicting mental illness.

    PubMed

    Nairn, R; Coverdale, J; Claasen, D

    2001-10-01

    The aim of this study was to analyse how newspaper articles that depict mental illnesses are generated from source materials. From a prospectively collected national sample of print materials involving mental illness, 50 published items that related to the Privacy Commissioner's opinion about disclosure of a psychiatric patient's health information were identified. A copy of the Privacy Commissioner's original Case Note and three news stories about the Case Note distributed by the New Zealand Press Association constituted the database. These materials were subjected to discourse analysis. We identified themes and their transformation from the Case Note through the news stories and examined the impact of these transformations on the stigmatization of mental illness. Four themes were identified: human rights, vulnerability, risk of dangerousness and threat, and mental illness/psychiatric patient. The only potentially positive theme, human rights, was limited both by being fragmented in the source material, and by being utilized, in the published news stories to undermine the legitimacy of the patient's right to privacy. Use of the other themes was consistent with stereotypes about mental illness. Although there were no inaccuracies in the content of the news stories they were substantially more negative than the source material in their depiction of the identified patient. A potentially positive discourse (human rights) was not by itself sufficient to ensure a positive portrayal of mental illness. An understanding of the transformations is important for efforts to effectively combat the stigmatization of those with mental illness.

  13. Real-time and accelerated outdoor endurance testing of solar cells

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Anagnostou, E.

    1978-01-01

    Materials for solar-cell module construction have been studied on the basis of limited real-time outdoor exposure evaluations. The materials tested included transmission samples, sub-modules, and actual solar cells. The results suggest that glass, fluorinated ethylene propylene, and perfluoroalkoxy are good materials for the covering or encapsulation of solar-cell modules. In all cases, dirt accumulation and cleanability are important factors.

  14. Process for producing dispersed particulate composite materials

    DOEpatents

    Henager, Jr., Charles H.; Hirth, John P.

    1995-01-01

    This invention is directed to a process for forming noninterwoven dispersed particulate composite products. In one case a composite multi-layer film product comprises a substantially noninterwoven multi-layer film having a plurality of discrete layers. This noninterwoven film comprises at least one discrete layer of a first material and at least one discrete layer of a second material. In another case the first and second materials are blended together with each other. In either case, the first material comprises a metalloid and the second material a metal compound. At least one component of a first material in one discrete layer undergoes a solid state displacement reaction with at least one component of a second material thereby producing the requisite noninterwoven composite film product. Preferably, the first material comprises silicon, the second material comprises Mo.sub.2 C, the third material comprises SiC and the fourth material comprises MoSi.sub.2.

  15. Enhancement of global flood damage assessments using building material based vulnerability curves

    NASA Astrophysics Data System (ADS)

    Englhardt, Johanna; de Ruiter, Marleen; de Moel, Hans; Aerts, Jeroen

    2017-04-01

    This study discusses the development of an enhanced approach for flood damage and risk assessments using vulnerability curves that are based on building material information. The approach draws upon common practices in earthquake vulnerability assessments, and is an alternative for land-use or building occupancy approach in flood risk assessment models. The approach is of particular importance for studies where there is a large variation in building material, such as large scale studies or studies in developing countries. A case study of Ethiopia is used to demonstrate the impact of the different methodological approaches on direct damage assessments due to flooding. Generally, flood damage assessments use damage curves for different land-use or occupancy types (i.e. urban or residential and commercial classes). However, these categories do not necessarily relate directly to vulnerability of damage by flood waters. For this, the construction type and building material may be more important, as is used in earthquake risk assessments. For this study, we use building material classification data of the PAGER1 project to define new building material based vulnerability classes for flood damage. This approach will be compared to the widely applied land-use based vulnerability curves such as used by De Moel et al. (2011). The case of Ethiopia demonstrates and compares the feasibility of this novel flood vulnerability method on a country level which holds the potential to be scaled up to a global level. The study shows that flood vulnerability based on building material also allows for better differentiation between flood damage in urban and rural settings, opening doors to better link to poverty studies when such exposure data is available. Furthermore, this new approach paves the road to the enhancement of multi-risk assessments as the method enables the comparison of vulnerability across different natural hazard types that also use material-based vulnerability curves. Finally, this approach allows for more accuracy in estimating losses as a result of direct damages. 1 http://earthquake.usgs.gov/data/pager/

  16. [Alternative biological materials to detect prenatal exposure to drugs of abuse in the third trimester of pregnancy].

    PubMed

    García-Serra, J; Ramis, J; Simó, S; Joya, X; Pichini, S; Vall, O; García-Algar, O

    2012-11-01

    Detection of prenatal drug abuse exposure is essential to ensure an appropriate monitoring of affected children. A maternal questionnaire is not an efficient screening tool. The usefulness of maternal hair and meconium as biological materials to assess this exposure has been described in last few years. The aim of this study was to compare both these alternative biological materials for prenatal drug exposure detection in the third trimester of pregnancy, in order to assess its use as a screening tool. Between January and March 2010, samples of maternal hair and meconium from 107 mother-infant dyads were collected in Can Misses Hospital, Ibiza. The presence of opiates, cocaine, cannabis, and amphetamines, was determined in both materials, using standard chromatographic techniques. Maternal hair analysis showed a 15.9% positivity for drugs of abuse (17 cases): 11 cannabis, 7 cocaine, 1 cannabis and ecstasy, and 1 cannabis and cocaine. Only one mother reported cannabis consumption and another one, cocaine. Of the 7 cocaine positive cases in hair, 6 were confirmed in meconium analysis, while of 11 cannabis positive cases, only 3 were confirmed in meconium. Two different consumer profiles were defined: cocaine consumers and cannabis consumers (with only 2 cases of multiple drug use). The highest level of cocaine ever published was detected (1.582ng/g) in one case. This study reveals a high prevalence of drug abuse in this cohort during pregnancy. Improved screening methods may optimize prevention and monitoring of exposed infants. Maternal hair seems to be more sensitive than meconium to detect prenatal exposure to cannabis during the third trimester, so it might become a good screening tool. Copyright © 2011 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  17. Modeling the dynamic crush of impact mitigating materials

    NASA Astrophysics Data System (ADS)

    Logan, R. W.; McMichael, L. D.

    1995-05-01

    Crushable materials are commonly utilized in the design of structural components to absorb energy and mitigate shock during the dynamic impact of a complex structure, such as an automobile chassis or drum-type shipping container. The development and application of several finite-element material models which have been developed at various times at LLNL for DYNA3D are discussed. Between the models, they are able to account for several of the predominant mechanisms which typically influence the dynamic mechanical behavior of crushable materials. One issue we addressed was that no single existing model would account for the entire gambit of constitutive features which are important for crushable materials. Thus, we describe the implementation and use of an additional material model which attempts to provide a more comprehensive model of the mechanics of crushable material behavior. This model combines features of the pre-existing DYNA models and incorporates some new features as well in an invariant large-strain formulation. In addition to examining the behavior of a unit cell in uniaxial compression, two cases were chosen to evaluate the capabilities and accuracy of the various material models in DYNA. In the first case, a model for foam filled box beams was developed and compared to test data from a four-point bend test. The model was subsequently used to study its effectiveness in energy absorption in an aluminum extrusion, spaceframe, vehicle chassis. The second case examined the response of the AT-400A shipping container and the performance of the overpack material during accident environments selected from 10CFR71 and IAEA regulations.

  18. Lithium potential variations for metastable materials: case study of nanocrystalline and amorphous LiFePO4.

    PubMed

    Zhu, Changbao; Mu, Xiaoke; Popovic, Jelena; Weichert, Katja; van Aken, Peter A; Yu, Yan; Maier, Joachim

    2014-09-10

    Much attention has been paid to metastable materials in the lithium battery field, especially to nanocrystalline and amorphous materials. Nonetheless, fundamental issues such as lithium potential variations have not been pertinently addressed. Using LiFePO4 as a model system, we inspect such lithium potential variations for various lithium storage modes and evaluate them thermodynamically. The conclusions of this work are essential for an adequate understanding of the behavior of electrode materials and even helpful in the search for new energy materials.

  19. Applicable research in practice: understanding the hydrophilic and flow property measurements of impression materials.

    PubMed

    Perry, Ronald D; Goldberg, Jeffrey A; Benchimol, Jacques; Orfanidis, John

    2006-10-01

    The flow properties and hydrophilicity of an impression material are key factors that affect its performance. This article details in vitro studies comparing these properties in 1 polyether and several vinyl polysiloxane light-body impression materials. The first series of studies examined the materials' flow properties used in a "shark fin" measurement procedure to determine which exhibited superior flow characteristics. The second series of studies reviewed the hydrophilic properties of the materials. Video analysis was used to record contact angle measurements at the early- and late-stage working times. Results showed 1 polyether material to be more hydrophilic. Applying this knowledge to practice, the authors present a clinical case in which a polyether's superior flow and quality of detail were used to make impressions for a patient receiving 8 single-unit zirconia crowns.

  20. On entropy change measurements around first order phase transitions in caloric materials.

    PubMed

    Caron, Luana; Ba Doan, Nguyen; Ranno, Laurent

    2017-02-22

    In this work we discuss the measurement protocols for indirect determination of the isothermal entropy change associated with first order phase transitions in caloric materials. The magneto-structural phase transitions giving rise to giant magnetocaloric effects in Cu-doped MnAs and FeRh are used as case studies to exemplify how badly designed protocols may affect isothermal measurements and lead to incorrect entropy change estimations. Isothermal measurement protocols which allow correct assessment of the entropy change around first order phase transitions in both direct and inverse cases are presented.

  1. The role of initial coherence and path materials in the dynamics of three rock avalanche case histories

    USGS Publications Warehouse

    Aaron, Jordan; McDougall, Scott; Moore, Jeffrey R.; Coe, Jeffrey A.; Hungr, Oldrich

    2017-01-01

    BackgroundRock avalanches are flow-like landslides that can travel at extremely rapid velocities and impact surprisingly large areas. The mechanisms that lead to the unexpected mobility of these flows are unknown and debated. Mechanisms proposed in the literature can be broadly classified into those that rely on intrinsic characteristics of the rock avalanche material, and those that rely on extrinsic factors such as path material. In this work a calibration-based numerical model is used to back-analyze three rock avalanche case histories. The results of these back-analyses are then used to infer factors that govern rock avalanche motionResultsOur study has revealed two key insights that must be considered when analyzing rock avalanches. Results from two of the case histories demonstrate the importance of accounting for the initially coherent phase of rock avalanche motion. Additionally, the back-analyzed basal resistance parameters, as well as the best-fit rheology, are different for each case history. This suggests that the governing mechanisms controlling rock avalanche motion are unlikely to be intrinsic. The back-analyzed strength parameters correspond well to those that would be expected by considering the path material that the rock avalanches overran.ConclusionOur results show that accurate simulation of rock avalanche motion must account for the initially coherent phase of movement, and that the mechanisms governing rock avalanche motion are unlikely to be intrinsic to the failed material. Interaction of rock avalanche debris with path materials is the likely mechanism that governs the motion of many rock avalanches.

  2. Detecting Molecular Mobility in Cryopreserved Materials using Mechanical Properties: Seeds as a Case Study

    USDA-ARS?s Scientific Manuscript database

    The purpose of this presentation is to examine molecular mobility of materials stored under cryogenic conditions. It is generally assumed that molecular mobility of fluids decrease to almost nil once the temperature decreases to below the glass transition temperature, Tg. Glass transitions have b...

  3. Hazardous materials incident costs : estimating the costs of the March 25, 2004, tanker truck crash in Bridgeport, Connecticut

    DOT National Transportation Integrated Search

    2004-08-01

    Significant variations in the reporting of hazardous materials incident costs are illustrated using a case study of the March 2004 crash of a fuel tanker truck on Interstate 95 in Bridgeport, Connecticut. Three separate cost estimates are presented, ...

  4. Technique development for conducting mechanical tests to study the pore formation process in case of material fracture

    NASA Astrophysics Data System (ADS)

    Magomedova, D. K.; Efimov, M. A.; Murashkin, M. Yu.

    2018-05-01

    The main purpose of this work was the development of an experimental technique for search and analysis of pore formation in the presented material. Geometry of the samples, the procedure of experiment and processing the samples for investigation were developed.

  5. Creating Culturally Relevant Instructional Materials: A Swaziland Case Study

    ERIC Educational Resources Information Center

    Titone, Connie; Plummer, Emily C.; Kielar, Melissa A.

    2012-01-01

    In the field of English language learning, research proves that culturally relevant reading materials improve students' language acquisition, learning motivation, self-esteem, and identity formation. Since English is the language of instruction in many distant countries, such as Swaziland, even when English is not the native language of those…

  6. PHYTOREMEDIATION OF DREDGED SEDIMENTS: A CASE STUDY AT THE JONES ISLAND CDF

    EPA Science Inventory

    The Jones Island Confined Disposal Facility (CDF) is a 44 acre in-lake area that receives dredged material from Milwaukee Harbor and the surrounding waterways. Some of those materials are contaminated with industrial waste and urban run-off. The CDF is nearing the end of its desi...

  7. The effects of different types of investments on the alpha-case layer of titanium castings.

    PubMed

    Guilin, Yu; Nan, Li; Yousheng, Li; Yining, Wang

    2007-03-01

    Different types of investments affect the formation of the alpha-case (alpha-case) layer on titanium castings. This alpha-case layer may possibly alter the mechanical properties of cast titanium, which may influence the fabrication of removable and fixed prostheses. The formation mechanism for the alpha-case layer is not clear. The aim of this study was to evaluate the effect of 3 types of investments on the microstructure, composition, and microhardness of the alpha-case layer on titanium castings. Fifteen wax columns with a diameter of 5 mm and a length of 40 mm were divided into 3 groups of 5 patterns each. Patterns were invested using 3 types of investment materials, respectively, and were cast in pure titanium. The 3 types of materials tested were SiO(2)-, Al(2)O(3)-, and MgO-based investments. All specimens were sectioned and prepared for metallographic observation. The microstructure and composition of the surface reaction layer of titanium castings were investigated by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The surface microhardness (VHN) for all specimens was measured using a hardness testing machine, and a mean value for each group was calculated. The alpha-case layer on titanium castings invested with SiO(2)-, Al(2)O(3)-, and MgO-based investments consisted of 3 layers-namely, the oxide layer, alloy layer, and hardening layer. In this study, the oxide layer and alloy layer were called the reaction layer. The thickness of the reaction layer for titanium castings using SiO(2)-, Al(2)O(3)-, and MgO-based investments was approximately 80 microm, 50 microm, and 14 microm, respectively. The surface microhardness of titanium castings made with SiO(2)-based investments was the highest, and that with MgO-based investments was the lowest. The type of investment affects the microstructure and microhardness of the alpha-case layer of titanium castings. Based on the thickness of the surface reaction layer and the surface microhardness of titanium castings, MgO-based investment materials may be the best choice for casting these materials.

  8. Effect of Different Substrates and Casing Materials on the Growth and Yield of Calocybe indica.

    PubMed

    Amin, Ruhul; Khair, Abul; Alam, Nuhu; Lee, Tae Soo

    2010-06-01

    Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica.

  9. Effect of Different Substrates and Casing Materials on the Growth and Yield of Calocybe indica

    PubMed Central

    Amin, Ruhul; Khair, Abul; Alam, Nuhu

    2010-01-01

    Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica. PMID:23956634

  10. Fate and Transport of Chemical Warfare Agents VX and HD ...

    EPA Pesticide Factsheets

    Report The intent of this investigation was to study the fate and transport of CWA applied to painted/sealed materials including the potential partitioning of CWA into permeable paints/sealants and subsequently into underlying porous materials. Based on the results obtained from this investigation, VX and sulfur mustard (HD) have the ability to permeate into paints and sealants, including in some cases the underlying porous materials. It is likely that other permeable materials besides paints and sealants may also show similar behavior.

  11. Antioxidant properties of different edible mushroom species and increased bioconversion efficiency of Pleurotus eryngii using locally available casing materials.

    PubMed

    Mishra, K K; Pal, R S; Arunkumar, R; Chandrashekara, C; Jain, S K; Bhatt, J C

    2013-06-01

    Total phenolics, radical scavenging activity (RSA) on DPPH, ascorbic acid content and chelating activity on Fe(2+) of Pleurotus citrinopileatus, Pleurotus djamor, Pleurotus eryngii, Pleurotus flabellatus, Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor-caju and Hypsizygus ulmarius have been evaluated. The assayed mushrooms contained 3.94-21.67 mg TAE of phenolics, 13.63-69.67% DPPH scavenging activity, 3.76-6.76 mg ascorbic acid and 60.25-82.7% chelating activity. Principal Component Analysis (PCA) revealed that significantly higher total phenolics, RSA on DPPH and growth/day was present in P. eryngii whereas P. citrinopileatus showed higher ascorbic acid and chelating activity. Agglomerative hierarchical clustering analysis revealed that studied mushroom species fall into two clusters; Cluster I included P. djamor, P. eryngii and P. flabellatus, while Cluster II included H. ulmarius, P. sajor-caju, P. citrinopileatus, P. ostreatus and P. florida. Enhanced yield of P. eryngii was achieved on spent compost casing material. Use of casing materials enhanced yield by 21-107% over non-cased substrate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Silicone impression material foreign body in the middle ear: Two case reports and literature review.

    PubMed

    Suzuki, Nobuyoshi; Okamura, Koji; Yano, Takuya; Moteki, Hideaki; Kitoh, Ryosuke; Takumi, Yutaka; Usami, Shin-ichi

    2015-10-01

    We report two cases of impression material foreign body in the middle ear. The first case had been affected with chronic otitis media. The silicone flowed into the middle ear through a tympanic membrane perforation during the process of making an ear mold. About 4 years and 8 months after, the patient had severe vertigo and deafness. We found bone erosion of the prominence of the lateral semicircular canal and diagnosed labyrinthitis caused by silicone impression material. In the second case silicone flowed into the canal wall down mastoid cavity. Both cases required surgery to remove the foreign body. The clinical courses in such cases are variable and timing of surgery is sometimes difficult. In addition to reporting these two cases, we present here a review of the literature regarding impression material foreign bodies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. MECP2 duplications in six patients with complex sex chromosome rearrangements

    PubMed Central

    Breman, Amy M; Ramocki, Melissa B; Kang, Sung-Hae L; Williams, Misti; Freedenberg, Debra; Patel, Ankita; Bader, Patricia I; Cheung, Sau Wai

    2011-01-01

    Duplications of the Xq28 chromosome region resulting in functional disomy are associated with a distinct clinical phenotype characterized by infantile hypotonia, severe developmental delay, progressive neurological impairment, absent speech, and proneness to infections. Increased expression of the dosage-sensitive MECP2 gene is considered responsible for the severe neurological impairments observed in affected individuals. Although cytogenetically visible duplications of Xq28 are well documented in the published literature, recent advances using array comparative genomic hybridization (CGH) led to the detection of an increasing number of microduplications spanning MECP2. In rare cases, duplication results from intrachromosomal rearrangement between the X and Y chromosomes. We report six cases with sex chromosome rearrangements involving duplication of MECP2. Cases 1–4 are unbalanced rearrangements between X and Y, resulting in MECP2 duplication. The additional Xq material was translocated to Yp in three cases (cases 1–3), and to the heterochromatic region of Yq12 in one case (case 4). Cases 5 and 6 were identified by array CGH to have a loss in copy number at Xp and a gain in copy number at Xq28 involving the MECP2 gene. In both cases, fluorescent in situ hybridization (FISH) analysis revealed a recombinant X chromosome containing the duplicated material from Xq28 on Xp, resulting from a maternal pericentric inversion. These cases add to a growing number of MECP2 duplications that have been detected by array CGH, while demonstrating the value of confirmatory chromosome and FISH studies for the localization of the duplicated material and the identification of complex rearrangements. PMID:21119712

  14. Full space device optimization for solar cells.

    PubMed

    Baloch, Ahmer A B; Aly, Shahzada P; Hossain, Mohammad I; El-Mellouhi, Fedwa; Tabet, Nouar; Alharbi, Fahhad H

    2017-09-20

    Advances in computational materials have paved a way to design efficient solar cells by identifying the optimal properties of the device layers. Conventionally, the device optimization has been governed by single or double descriptors for an individual layer; mostly the absorbing layer. However, the performance of the device depends collectively on all the properties of the material and the geometry of each layer in the cell. To address this issue of multi-property optimization and to avoid the paradigm of reoccurring materials in the solar cell field, a full space material-independent optimization approach is developed and presented in this paper. The method is employed to obtain an optimized material data set for maximum efficiency and for targeted functionality for each layer. To ensure the robustness of the method, two cases are studied; namely perovskite solar cells device optimization and cadmium-free CIGS solar cell. The implementation determines the desirable optoelectronic properties of transport mediums and contacts that can maximize the efficiency for both cases. The resulted data sets of material properties can be matched with those in materials databases or by further microscopic material design. Moreover, the presented multi-property optimization framework can be extended to design any solid-state device.

  15. Human Studies of Vertical and Horizontal Alveolar Ridge Augmentation Comparing Different Types of Bone Graft Materials: A Systematic Review.

    PubMed

    Chavda, Suraj; Levin, Liran

    2018-02-01

    Alveolar ridge augmentation can be completed with various types of bone augmentation materials (autogenous, allograft, xenograft, and alloplast). Currently, autogenous bone is labeled as the "gold standard" because of faster healing times and integration between native and foreign bone. No systematic review has currently determined whether there is a difference in implant success between various bone augmentation materials. The purpose of this article was to systematically review comparative human studies of vertical and horizontal alveolar ridge augmentation comparing different types of bone graft materials (autogenous, allograft, xenograft, and alloplast). A MEDLINE search was conducted under the 3 search concepts of bone augmentation, dental implants, and alveolar ridge augmentation. Studies pertaining to socket grafts or sinus lifts were excluded. Case reports, small case series, and review papers were excluded. A bias assessment tool was applied to the final articles. Overall, 219 articles resulted from the initial search, and 9 articles were included for final analysis. There were no discernible differences in implant success between bone augmentation materials. Generally, patients preferred nonautogenous bone sources as there were fewer hospital days, less pain, and better recovery time. Two articles had industrial support; however, conclusions of whether that support influenced the outcomes could not be determined. Future comparative studies should compare nonautogenous bone sources and have longer follow-up times.

  16. Forensic engineering of advanced polymeric materials Part IV: Case study of oxo-biodegradable polyethylene commercial bag - Aging in biotic and abiotic environment.

    PubMed

    Musioł, Marta; Rydz, Joanna; Janeczek, Henryk; Radecka, Iza; Jiang, Guozhan; Kowalczuk, Marek

    2017-06-01

    The public awareness of the quality of environment stimulates the endeavor to safe polymeric materials and their degradation products. The aim of the forensic engineering case study presented in this paper is to evaluate the aging process of commercial oxo-degradable polyethylene bag under real industrial composting conditions and in distilled water at 70°C, for comparison. Partial degradation of the investigated material was monitored by changes in molecular weight, thermal properties and Keto Carbonyl Bond Index and Vinyl Bond Index, which were calculated from the FTIR spectra. The results indicate that such an oxo-degradable product offered in markets degrades slowly under industrial composting conditions. Even fragmentation is slow, and it is dubious that biological mineralization of this material would occur within a year under industrial composting conditions. The slow degradation and fragmentation is most likely due to partially crosslinking after long time of degradation, which results in the limitation of low molecular weight residues for assimilation. The work suggests that these materials should not be labeled as biodegradable, and should be further analyzed in order to avoid the spread of persistent artificial materials in nature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Replacing Lectures with Small Groups: The Impact of Flipping the Residency Conference Day

    PubMed Central

    King, Andrew M.; Mayer, Chad; Barrie, Michael; Greenberger, Sarah; Way, David P.

    2018-01-01

    The flipped classroom, an educational alternative to the traditional lecture, has been widely adopted by educators at all levels of education and across many disciplines. In the flipped classroom, learners prepare in advance of the face-to-face meeting by learning content material on their own. Classroom time is reserved for application of the learned content to solving problems or discussing cases. Over the past year, we replaced most residency program lectures with small-group discussions using the flipped-classroom model, case-based learning, simulation and procedure labs. In the new model, residents prepared for conference by reviewing a patient case and studying suggested learning materials. Conference day was set aside for facilitated small-group discussions about the case. This is a cross-cohort study of emergency medicine residents who experienced the lecture-based curriculum to residents in the new flipped-classroom curriculum using paired comparisons (independent t-tests) on in-training exam scores while controlling for program year level. We also compared results of the evaluation of various program components. We observed no differences between cohorts on in-training examination scores. Small-group methods were rated the same across program years. Two program components in the new curriculum, an updated format of both adult and pediatric case conferences, were rated significantly higher on program quality. In preparation for didactics, residents in the new curriculum report spending more time on average with outside learning materials, including almost twice as much time reviewing textbooks. Residents found the new format of the case conferences to be of higher quality because of the inclusion of rapid-fire case discussions with targeted learning points. PMID:29383050

  18. Research in Accrediting Efforts (Project REA). An Assessment on the Awarding of Academic Credit for CETA Activities in Illinois. Case Studies.

    ERIC Educational Resources Information Center

    Stoyanoff, Karen, Comp.; Klehm, Jeanette, Comp.

    Summaries are presented of 15 case studies conducted at Illinois Comprehensive Employment and Training Act (CETA) regions to determine the kind of credentialing mechanisms that exist for awarding academic credit or some other record of achievement to those eligible participants who complete CETA training programs. Introductory material describes…

  19. Dialogic Instruction and Learning: The Case of One Kiswahili Classroom in Kenya

    ERIC Educational Resources Information Center

    Lisanza, Esther Mukewa

    2014-01-01

    This paper reports on an ethnographic case study which was carried out in a Kenyan first-grade classroom. The classroom had 89 students with their 2 teachers who taught at different times. The classroom was very crowded and had a high paucity of literacy materials. The study was guided by sociocultural and dialogic frameworks which maintain that…

  20. Chair Report Consultancy Meeting on Nuclear Security Assessment Methodologies (NUSAM) Transport Case Study Working Group

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shull, Doug

    The purpose of the consultancy assignment was to (i) apply the NUSAM assessment methods to hypothetical transport security table top exercise (TTX) analyses and (ii) document its results to working materials of NUSAM case study on transport. A number of working group observations, using the results of TTX methodologies, are noted in the report.

  1. Integrating Learning, Leadership, and Crisis in Management Education: Lessons from Army Officers in Iraq and Afghanistan

    ERIC Educational Resources Information Center

    Kayes, D. Christopher; Allen, Nate; Self, Nate

    2013-01-01

    This article presents a model and case study used to teach crisis leadership as a management education topic. The materials emerge from studies of U.S. Army leaders (company commanders and platoon leaders) working in Iraq and Afghanistan. The authors explain how examples and cases from military combat provide tools to teach about crisis…

  2. Elementary Social Studies in 2005: Danger or Opportunity?--A Response to Jeff Passe

    ERIC Educational Resources Information Center

    Libresco, Andrea S.

    2006-01-01

    From the emphasis on lower-level test-prep materials to the disappearance of the subject altogether, elementary social studies is, in the best case scenario, being tested and, thus, taught with a heavy emphasis on recall; and, in the worst-case scenario, not being taught at all. In this article, the author responds to Jeff Passe's views on…

  3. Scaffolded Writing and Early Literacy Development with Children Who Are Deaf: A Case Study

    ERIC Educational Resources Information Center

    Scott-Weich, Bridget; Yaden, David B., Jr.

    2017-01-01

    This case study examined the effects that the processes of private speech and materialization (using line underscores as word placeholders) had on the emergent writing behaviours of one, six-year-old student who was enrolled in an auditory--oral deaf or hard of hearing (DHH) first-grade classroom situated on a large urban public school campus.…

  4. Making things explicit using instructional materials: a case study of a Singapore teacher's practice

    NASA Astrophysics Data System (ADS)

    Leong, Yew Hoong; Cheng, Lu Pien; Toh, Wei Yeng Karen; Kaur, Berinderjeet; Toh, Tin Lam

    2018-04-01

    The phrase `make it explicit' is a common advice given to teachers. It is, however, not clear to us what this actually means when translated into classroom practice. Our review found that we are not alone: "explicit" is used in different ways in the education literature. This paper explores, through a case study of a teacher who stated "making things explicit" as an ostensible goal of his instructional practice, how the explicitation is realised in teaching mathematics. In particular, we examine how he used the instructional materials that he crafted to fulfil his goal of explicitation. We were able to uncover three strategies he used: explicit-from, explicit-within, and explicit-to.

  5. Sub-fragmentation of structural-reactive-material casings under explosion

    NASA Astrophysics Data System (ADS)

    Zhang, Fan

    2015-06-01

    The sub-fragmentation of structural reactive material (SRM) thick-casings is to generate fine fragments during casing fragmentation under explosive loading for their efficient energy release to enhance air blast. This has been investigated using a cylindrical casing made from either rich Al-MoO3 or Al-W-based granular composites. The former composite was to study the concept of reactive hot spots where the reaction of reactive particles, which were distributed into base SRM in a fuel-rich equivalence ratio, created heat and gas products during SRM fragmentation. The expansion of these distributed hot spots initiated local fractures of the casing, leading to fine fragments. The Al-W-based composite investigated the concept of impedance mismatch, where shock dynamics at the interfaces of different impedance ingredients resulted in non-uniform, high local temperatures and stresses and late in times the dissimilar inertia resulted in different accelerations, leading to material separation and fine fragments. The casings were manufactured through both hot iso-static pressing and cold gas dynamic spray deposition. Explosion experiments were conducted in a 3 m diameter, 23 m3 cylindrical chamber for these cased charges in a casing-to-explosive mass ratio of 1.75. The results demonstrated the presence of fine fragments and more efficient fragment combustion, compared with previous results, and indicated the effectiveness of both concepts. This work was jointly funded by Defence R&D Canada and the Advanced Energetics Program of DTRA (Dr. William H. Wilson).

  6. Allergic Reactions to Dental Materials-A Systematic Review

    PubMed Central

    Chopra, Radhika; Sachdev, Vinod

    2015-01-01

    Introduction Utility of various dental materials ranging from diagnosis to rehabilitation for the management of oral diseases are not devoid of posing a potential risk of inducing allergic reactions to the patient, technician and dentist. This review aims to develop a systematic approach for the selection and monitoring of dental materials available in the market thereby giving an insight to predict their risk of inducing allergic reactions. Materials and Methods Our data included 71 relevant articles which included 60 case reports, 8 prospective studies and 3 retrospective studies. The source of these articles was Pub Med search done with the following terms: allergies to impression materials, sodium hypochlorite, Ledermix paste, zinc oxide eugenol, formaldehyde, Latex gloves, Methyl methacrylate, fissure sealant, composites, mercury, Nickel-chromium, Titanium, polishing paste and local anaesthesia. All the relevant articles and their references were analysed. The clinical manifestations of allergy to different dental materials based on different case reports were reviewed. Results After reviewing the literature, we found that the dental material reported to cause most adverse reactions in patients is amalgam and the incidence of oral lichenoid reactions adjacent to amalgam restorations occur more often than other dental materials. Conclusion The most common allergic reactions in dental staff are allergies to latex, acrylates and formaldehyde. While polymethylmethacrylates and latex trigger delayed hypersensitivity reactions, sodium metabisulphite and nickel cause immediate reactions. Over the last few years, due to the rise in number of patients with allergies from different materials, the practicing dentists should have knowledge about documented allergies to known materials and thus avoid such allergic manifestations in the dental clinic. PMID:26557634

  7. 7 CFR 1726.21 - New materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false New materials. 1726.21 Section 1726.21 Agriculture... ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES General § 1726.21 New materials. The borrower shall purchase only new materials and equipment unless otherwise approved by RUS, on a case by case basis, prior...

  8. 7 CFR 1726.21 - New materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false New materials. 1726.21 Section 1726.21 Agriculture... ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES General § 1726.21 New materials. The borrower shall purchase only new materials and equipment unless otherwise approved by RUS, on a case by case basis, prior...

  9. Rapid identification of areas of interest in thin film materials libraries by combining electrical, optical, X-ray diffraction, and mechanical high-throughput measurements: a case study for the system Ni-Al.

    PubMed

    Thienhaus, S; Naujoks, D; Pfetzing-Micklich, J; König, D; Ludwig, A

    2014-12-08

    The efficient identification of compositional areas of interest in thin film materials systems fabricated by combinatorial deposition methods is essential in combinatorial materials science. We use a combination of compositional screening by EDX together with high-throughput measurements of electrical and optical properties of thin film libraries to determine efficiently the areas of interest in a materials system. Areas of interest are compositions which show distinctive properties. The crystallinity of the thus determined areas is identified by X-ray diffraction. Additionally, by using automated nanoindentation across the materials library, mechanical data of the thin films can be obtained which complements the identification of areas of interest. The feasibility of this approach is demonstrated by using a Ni-Al thin film library as a reference system. The obtained results promise that this approach can be used for the case of ternary and higher order systems.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Versino, Daniele; Brock, Jerry Steven

    In this manuscript we describe test cases for the dynamic sphere problem in presence of finite deformations. The spherical shell in exam is made of a homogeneous, isotropic or transverse isotropic material and elastic and elastic-plastic material behaviors are considered. Twenty cases, (a) to (t), are thus defined combining material types and boundary conditions. The inner surface radius, the outer surface radius and the material's density are kept constant for all the considered test cases and their values are r i = 10mm, r o = 20mm and p = 1000Kg/m 3 respectively.

  11. A new data-processing approach to study particle motion using ultrafast X-ray tomography scanner: case study of gravitational mass flow

    NASA Astrophysics Data System (ADS)

    Waktola, Selam; Bieberle, Andre; Barthel, Frank; Bieberle, Martina; Hampel, Uwe; Grudzień, Krzysztof; Babout, Laurent

    2018-04-01

    In most industrial products, granular materials are often required to flow under gravity in various kinds of silo shapes and usually through an outlet in the bottom. There are several interrelated parameters which affect the flow, such as internal friction, bulk and packing density, hopper geometry, and material type. Due to the low-spatial resolution of electrical capacitance tomography or scanning speed limitation of standard X-ray CT systems, it is extremely challenging to measure the flow velocity and possible centrifugal effects of granular materials flow effectively. However, ROFEX (ROssendorf Fast Electron beam X-ray tomography) opens new avenues of granular flow investigation due to its very high temporal resolution. This paper aims to track particle movements and evaluate the local grain velocity during silo discharging process in the case of mass flow. The study has considered the use of the Seramis material, which can also serve as a type of tracer particles after impregnation, due to its porous nature. The presented novel image processing and analysis approach allows satisfyingly measuring individual particle velocities but also tracking their lateral movement and three-dimensional rotations.

  12. Impact of interfacial imperfection on transverse wave in a functionally graded piezoelectric material structure with corrugated boundaries

    NASA Astrophysics Data System (ADS)

    Kumar Singh, Abhishek; Kumar, Santan; Kumari, Richa

    2018-03-01

    The propagation behavior of Love-type wave in a corrugated functionally graded piezoelectric material layered structure has been taken into account. Concretely, the layered structure incorporates a corrugated functionally graded piezoelectric material layer imperfectly bonded to a functionally graded piezoelectric material half-space. An analytical treatment has been employed to determine the dispersion relation for both cases of electrically open condition and electrically short condition. The phase velocity of the Love-type wave has been computed numerically and its dependence on the wave number has been depicted graphically for a specific type of corrugated boundary surfaces for both said conditions. The crux of the study lies in the fact that the imperfect bonding of the interface, the corrugated boundaries present in the layer, and the material properties of the layer and the half-space strongly influence the phase velocity of the Love-type wave. It can be remarkably noted that the imperfect bonding of the interface reduces the phase velocity of the Love-type wave significantly. As a special case of the problem, it is noticed that the procured dispersion relation for both cases of electrically open and electrically short conditions is in accordance with the classical Love wave equation.

  13. Translating Current Science into Materials for High School via a Scientist-Teacher Partnership

    NASA Astrophysics Data System (ADS)

    Brown, Julie C.; Bokor, Julie R.; Crippen, Kent J.; Koroly, Mary Jo

    2014-04-01

    Scientist-teacher partnerships are a unique form of professional development that can assist teachers in translating current science into classroom instruction by involving them in meaningful collaborations with university researchers. However, few reported models aim to directly alter science teachers' practices by supporting them in the development of curriculum materials. This article reports on a multiple case study of seven high school science teachers who attended an ongoing scientist-teacher partnership professional development program at a major Southeastern research university. Our interest was to understand the capacity of this professional development program for supporting teachers in the transfer of personal learning experiences with advanced science content and skills into curriculum materials for high school students. Findings indicate that, regardless of their ultimate success constructing curriculum materials, all cases considered the research grounded professional development supports beneficial to their professional growth with the exception of collective participation. Additionally, the cases also described how supports such as professional recognition and transferability served as affordances to the process of constructing these materials. However, teachers identified multiple constraints, including personal learning barriers, their classroom context, and the cost associated with implementing some of their curriculum ideas. Results have direct implications for future research and the purposeful design of professional development experiences through scientist-teacher partnerships.

  14. 3D-CFD analysis of diffusion and emission of VOCs in a FLEC cavity.

    PubMed

    Zhu, Q; Kato, S; Murakami, S; Ito, K

    2007-06-01

    This study is performed as a part of research that examines the emission and diffusion characteristics of volatile organic compounds (VOCs) from indoor building materials. In this paper, the flow field and the emission field of VOCs from the surface of building materials in a Field and Laboratory Emission Cell (FLEC) cavity are examined by 3D Computational Fluid Dynamics (CFD) analysis. The flow field within the FLEC cavity is laminar. With a total flow of 250 ml/min, the air velocity near the test material surface ranges from 0.1 to 4.5 cm/s. Three types of emission from building materials are studied here: (i) emission phenomena controlled by internal diffusion, (ii) emission phenomena controlled by external diffusion, and (iii) emission phenomena controlled by mixed diffusion (internal + external diffusion). In the case of internal diffusion material, with respect to the concentration distribution in the cavity, the local VOC emission rate becomes uniform and the FLEC works well. However, in the case of evaporation type (external diffusion) material, or mixed type materials (internal + external diffusion) when the resistance to transporting VOCs in the material is small, the FLEC is not suitable for emission testing because of the thin FLEC cavity. In this case, the mean emission rate is restricted to a small value, since the VOC concentration in the cavity rises to the same value as the surface concentration through molecular diffusion within the thin cavity, and the concentration gradient normal to the surface becomes small. The diffusion field and emission rate depend on the cavity concentration and on the Loading Factor. That is, when the testing material surface in the cavity is partially sealed to decrease the Loading Factor, the emission rate become higher with the decrease in the exposed area of the testing material. The flow field and diffusion field within the FLEC cavity are investigated by CFD method. After presenting a summary of the velocity distributed over the surface of test material and the emission properties of different type materials in FLEC, the paper pointed out that there is a bias in the airflow inside the FLEC cavity but do not influence the result of test emission rate, and the FLEC method is unsuitable for evaporation type materials in which the mass transfer of the surface controls the emission rate.

  15. The liquid wood heat flow and material properties as a function of temperature

    NASA Astrophysics Data System (ADS)

    Mazurchevici, Simona; Quadrini, Fabrizio; Nedelcu, Dumitru

    2018-03-01

    There are three types of ‘liquid wood’, Arbofill, Arboblend and Arboform and will replace plastics materials in the near future taking into account the biodegradability and higher properties versus common used plastics materials. In order to get more information about the materials properties of ‘liquid wood’ the granules and samples obtained by injection molding were studied using Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) for Arboform L,V3 Nature-‘liquid wood’ (A-LW) and Arboform L, V3 Nature reinforced with Aramid Fibers (A-LWAF).In case of A-LW granule studied, the DSC analysis presents that at 97 °C appears an endoderm peak which represents the crystallization of the material, at 175 °C the exoderm peak which means the melting point of the material. After the tested granule cooling period of time this one was tested again and the endoderm peak disappears, which means that crystallization of material disappeared. The melting point of the second test decreases slightly at 174.6 °C. Also, the new test shows that at 61.7 °C the glass transition temperature appears and the melting point slightly decreases. In case of A-LW samples the DSC analyses shows that the melting point increased by 2.77 °C compared to the melting point of Arboform granule. The material behavior is more or less the same without the crystallization area.

  16. Analyzing workplace exposures using direct reading instruments and video exposure monitoring techniques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gressel, M.G.; Heitbrink, W.A.; Jensen, P.A.

    1992-08-01

    The techniques for conducting video exposure monitoring were described along with the equipment required to monitor and record worker breathing zone concentrations, the analysis of the real time exposure data using video recordings, and the use of real time concentration data from a direct reading instrument to determine the effective ventilation rate and the mixing factor of a given room at a specific time. Case studies which made use of video exposure monitoring techniques to provide information not available through integrated sampling were also discussed. The process being monitored and the methodology used to monitor the exposures were described formore » each of the case studies. The case studies included manual material weigh out, ceramic casting cleaning, dumping bags of powdered materials, furniture stripping, administration of nitrous-oxide during dental procedures, hand held sanding operation, methanol exposures in maintenance garages, brake servicing, bulk loading of railroad cars and trucks, and grinding operations.« less

  17. Distance Learners' Perspective on User-Friendly Instructional Materials at the University of Zambia

    ERIC Educational Resources Information Center

    Simui, F.; Thompson, L. C.; Mundende, K.; Mwewa, G.; Kakana, F.; Chishiba, A.; Namangala, B.

    2017-01-01

    This case study focuses on print-based instructional materials available to distance education learners at the University of Zambia. Using the Visual Paradigm Software, we model distance education learners' voices into sociograms to make a contribution to the ongoing discourse on quality distance learning in poorly resourced communities. Emerging…

  18. Teaching Shakespeare: Materials and Outcomes for Web-Based Instruction and Class Adjunct.

    ERIC Educational Resources Information Center

    Schwartz, Helen J.

    Multimedia hypertext materials have instructional advantages when used as adjuncts in traditional classes and as the primary means of instruction, as illustrated in this case study of college-level Shakespeare classes. Plays become more accessible through use of audio and video resources, including video clips from play productions. Student work…

  19. Remembering George Washington: What Do Instructional Materials Teach Us about Washington's Patriotism?

    ERIC Educational Resources Information Center

    Fitzgerald, Jason C.

    2011-01-01

    History textbooks have long been criticized for their adherence to the "stabilized national narrative" (VanSledright 1998). However, teachers need to also be aware of the ideological influences of the supplemental instructional materials they choose. A case study of the Donald W. Reynolds Museum and Education Center at Mount Vernon illustrates…

  20. Using Video Materials in English for Technical Sciences: A Case Study

    ERIC Educational Resources Information Center

    Milosevic, Danica

    2017-01-01

    In the digital era, university instructors working in English for Technical Sciences (ETS) have opportunities, some might say obligations, to use audio-visual resources to motivate students. Such materials also call on cognitive and constructivist mechanisms thought to improve uptake of the target language (Tarnopolsky, 2012). This chapter reports…

  1. Simplified Application of Material Efficiency Green Metrics to Synthesis Plans: Pedagogical Case Studies Selected from "Organic Syntheses"

    ERIC Educational Resources Information Center

    Andraos, John

    2015-01-01

    This paper presents a simplified approach for the application of material efficiency metrics to linear and convergent synthesis plans encountered in organic synthesis courses. Computations are facilitated and automated using intuitively designed Microsoft Excel spreadsheets without invoking abstract mathematical formulas. The merits of this…

  2. Pedagogical Design Capacity and Underlying Knowledge Base of Curriculum Materials Use of a Hong Kong English Teacher

    ERIC Educational Resources Information Center

    Chong, Ivan

    2016-01-01

    Using "pedagogical design capacity" ("PDC") as the conceptual framework, this single-case study examines how an English teacher in Hong Kong perceives and mobilizes curriculum materials to teach reading comprehension to secondary one students in two stages of implementation. Relying on data collected from semi-structured…

  3. Student Teachers' Engagement with Re-Contextualized Materials: A Case of Numerical Approximation

    ERIC Educational Resources Information Center

    Brijlall, Deonarain; Bansilal, Sarah

    2011-01-01

    This paper reports on an exploration of students' learning derived from the implementation of learning materials developed in a previous collaborative project. The purpose of the study was to examine the development of third-year students' understanding of the Reimann Sum. These concepts were taught to undergraduate teacher trainees wishing to…

  4. A framework for sustainable nanomaterial selection and design based on performance, hazard, and economic considerations.

    PubMed

    Falinski, Mark M; Plata, Desiree L; Chopra, Shauhrat S; Theis, Thomas L; Gilbertson, Leanne M; Zimmerman, Julie B

    2018-04-30

    Engineered nanomaterials (ENMs) and ENM-enabled products have emerged as potentially high-performance replacements to conventional materials and chemicals. As such, there is an urgent need to incorporate environmental and human health objectives into ENM selection and design processes. Here, an adapted framework based on the Ashby material selection strategy is presented as an enhanced selection and design process, which includes functional performance as well as environmental and human health considerations. The utility of this framework is demonstrated through two case studies, the design and selection of antimicrobial substances and conductive polymers, including ENMs, ENM-enabled products and their alternatives. Further, these case studies consider both the comparative efficacy and impacts at two scales: (i) a broad scale, where chemical/material classes are readily compared for primary decision-making, and (ii) within a chemical/material class, where physicochemical properties are manipulated to tailor the desired performance and environmental impact profile. Development and implementation of this framework can inform decision-making for the implementation of ENMs to facilitate promising applications and prevent unintended consequences.

  5. Under-reporting of accidents involving biological material by nursing professionals at a Brazilian emergency hospital.

    PubMed

    Facchin, Luiza Tayar; Gir, Elucir; Pazin-Filho, Antonio; Hayashida, Miyeko; da Silva Canini, Silvia Rita Marin

    2013-01-01

    Pathogens can be transmitted to health professionals after contact with biological material. The exact number of infections deriving from these events is still unknown, due to the lack of systematic surveillance data and under-reporting. A cross-sectional study was carried out, involving 451 nursing professionals from a Brazilian tertiary emergency hospital between April and July 2009. Through an active search, cases of under-reporting of occupational accidents with biological material by the nursing team were identified by means of individual interviews. The Institutional Review Board approved the research project. Over half of the professionals (237) had been victims of one or more accidents (425 in total) involving biological material, and 23.76% of the accidents had not been officially reported using an occupational accident report. Among the underreported accidents, 53.47% were percutaneous and 67.33% were bloodborne. The main reason for nonreporting was that the accident had been considered low risk. The under-reporting rate (23.76%) was low in comparison with other studies, but most cases of exposure were high risk.

  6. Evaluation of Dielectric-Barrier-Discharge Actuator Substrate Materials

    NASA Technical Reports Server (NTRS)

    Wilkinson, Stephen P.; Siochi, Emilie J.; Sauti, Godfrey; Xu, Tian-Bing; Meador, Mary Ann; Guo, Haiquan

    2014-01-01

    A key, enabling element of a dielectric barrier discharge (DBD) actuator is the dielectric substrate material. While various investigators have studied the performance of different homogeneous materials, most often in the context of related DBD experiments, fundamental studies focused solely on the dielectric materials have received less attention. The purpose of this study was to conduct an experimental assessment of the body-force-generating performance of a wide range of dielectric materials in search of opportunities to improve DBD actuator performance. Materials studied included commonly available plastics and glasses as well as a custom-fabricated polyimide aerogel. Diagnostics included static induced thrust, electrical circuit parameters for 2D surface discharges and 1D volume discharges, and dielectric material properties. Lumped-parameter circuit simulations for the 1D case were conducted showing good correspondence to experimental data provided that stray capacitances are included. The effect of atmospheric humidity on DBD performance was studied showing a large influence on thrust. The main conclusion is that for homogeneous, dielectric materials at forcing voltages less than that required for streamer formation, the material chemical composition appears to have no effect on body force generation when actuator impedance is properly accounted for.

  7. Cytomorphology of cervicovaginal melanoma: ThinPrep versus conventional Papanicolaou tests

    PubMed Central

    Setia, Namrata; Goulart, Robert A; Leiman, Gladywn; Otis, Christopher N; Modem, Rukmini; Pantanowtiz, Liron

    2010-01-01

    Background: Primary cervicovaginal melanoma is a rare malignancy associated with a high risk of recurrence. Prior studies discussing the cytomorphology of cervicovaginal melanoma have been based primarily on review of conventional Papanicolaou (Pap) smears. The aim of this study was to evaluate cervicovaginal melanomas identified in liquid-based Pap tests, in comparison with features seen on conventional Pap smear preparation. Materials and Methods: Cases of cervicovaginal melanoma identified on Pap tests with concurrent or subsequent histopathologic confirmation were collected from the Baystate Medical Center cytopathology files and personal archives of the authors over a total period of 34 years. All cytopathology (n = 6) and the available histology slides (n = 5) were reviewed. Cases were analyzed regarding clinical, histopathologic and cytomorphological findings. Results: A total of six cases with invasive cervicovaginal melanoma diagnosed on Pap tests were identified. Most patients were postmenopausal with contact bleeding, correlating with surface ulceration (identified in biopsy/excision material in 5/5 cases). Most cases had deeply invasive tumors (5/5: modified Breslow's thickness > 5 mm and Chung's level of invasion IV/V). Pap tests included four ThinPrep and two conventional smears. Overall, ThinPrep Pap tests exhibited a higher ratio of tumor cells to background squamous cells. While all Pap tests were bloodstained, tumor diathesis was prominent only within conventional smears. Melanoma cells were present both as clusters and scattered single cells in each Pap test type. Both the preparations contained epithelioid tumor cells, whereas spindled tumor cells were seen in only two ThinPrep cases. Prominent nucleoli and binucleation of tumor cells were seen in both the preparations. Melanin pigment was identified in only ThinPrep (3/4) cases and nuclear pseudo-inclusions in one conventional Pap smear. Cell blocks were made in three ThinPrep cases and immunocytochemistry (S-100, HMB45, Melan-A) performed on additional vial material (one ThinPrep slide and one cell block) was immunoreactive in melanoma cells. Conclusion: Primary cervicovaginal melanoma, a rare malignancy seen predominantly in postmenopausal women, may be successfully diagnosed in either ThinPrep Pap tests or conventional Pap smears. While ThinPrep Pap tests did not demonstrate morphological advantage over conventional smears, liquid-based cytology specimens did provide additional material for cellblock preparation and immunocytochemical evaluation in a subset of cases. PMID:21298024

  8. Research on the development of green chemistry technology assessment techniques: a material reutilization case.

    PubMed

    Hong, Seokpyo; Ahn, Kilsoo; Kim, Sungjune; Gong, Sungyong

    2015-01-01

    This study presents a methodology that enables a quantitative assessment of green chemistry technologies. The study carries out a quantitative evaluation of a particular case of material reutilization by calculating the level of "greenness" i.e., the level of compliance with the principles of green chemistry that was achieved by implementing a green chemistry technology. The results indicate that the greenness level was enhanced by 42% compared to the pre-improvement level, thus demonstrating the economic feasibility of green chemistry. The assessment technique established in this study will serve as a useful reference for setting the direction of industry-level and government-level technological R&D and for evaluating newly developed technologies, which can greatly contribute toward gaining a competitive advantage in the global market.

  9. The Effect of School Culture on Science Education at an Ideologically Innovative Elementary Magnet School: An Ethnographic Case Study

    NASA Astrophysics Data System (ADS)

    Meier, Lori T.

    2012-11-01

    This ethnographic case study investigated the science practices of teachers at one public elementary magnet school in light of how school culture influenced science curriculum design and instruction. The purpose of the study was to address how school culture impacted the school's overall treatment of science as a viable content area. Key informant teachers were interviewed to explore their personal beliefs and values, teaching, access to materials, and views of the adopted integrated thematic curriculum model and magnet structure. The resulting data, triangulated with informal observation and artifact collection, were analyzed using a theoretical framework that emphasized five interdependent school culture indicators (values, beliefs, practices, materials, and problems). Findings suggest that the school's culture adversely influenced the treatment of science.

  10. Paleoenvironmental reconstruction of lagoonal strata from Sri Lanka using multiple physical properties proxies to assure stratigraphic continuity

    NASA Astrophysics Data System (ADS)

    Ranasinghage, P. N.; Ortiz, J. D.; Moore, A.; Siriwardana, C.

    2009-12-01

    Core collapsing is a common problem in studies of lagoonal sediment cores. Coring liquefied sediments below the water table can lead to collapse of material from upper core drives in to the hole. This can be prevented by casing the hole. But casing is not always possible due to practical issues such as coring device type, resources, or time constraints. In such cases identifying the collapsed material in each drive is necessary to ensure accurate results. Direct visual identification of collapsed portion is not always possible and may not be precise. This study successfully recognized collapsed material using a suite of physical properties measurements including: visible (VIS) reflectance spectroscopy, magnetic susceptibility and grain size spectra. This enables us to use the verified stratigraphically continuous records for paleo-environmental studies. Sediment cores were collected from three coastal lagoons and a swale along south eastern and eastern Sri Lanka. Cores were collected using a customized AMS soil coring device with a 1-m long sample barrel. The metal barrel of this instrument collects a 2.5 cm diameter sample in 1-m long plastic tubes. Coring was conducted to refusal, with a maximum depth of 5 m. Casing was not applied to the holes due to small core diameter and time constrains. Drill holes were placed at locations situated both below and above the water level of the lagoons. A total of 100 m of sediment core were obtained from these locations. After opening the cores, suspected collapsed material was initially identified by visual observation using a high power binocular microscope. Particle size, magnetic susceptibility, X-ray fluorescence (XRF) and Diffuse Spectral Reflectance (DSR) was then measured on all cores at 1-2 cm resolution to precisely define the repeated sediment intervals. Down core variation plots of magnetic susceptibility, CIE L* (lightness), a*(red/green difference), b* (blue and yellow difference) clearly record abrupt changes at core drive boundaries at the presence of collapsed material. The correlation of grain-size spectra from the bottom and top of consecutive drives was used to precisely determine the thickness of the collapsed material between drives. Our analysis of 48 m of core material thus far indicates that ~4.4m or ~9% of the record represents collapsed material which can be excluded from further study. The remaining continuous record was analyzed for paleoenvironmental studies. Down core variation of grain size, geochemical ratios, principle components of DSR and geochemical data, and magnetic susceptibility from all locations indicate a gradual filling of these deep lagoons and a transition from reducing to oxic conditions. According to an age model constructed for a nearby lagoon the onset of regression began ~6,000 years BP. Several instantaneous sedimentation events were recorded in all lagoons. Further studies will be carried out to determine whether these represent tsunami, storm surge, or flood deposits.

  11. The outcome of apical microsurgery using MTA as the root-end filling material: 2- to 6-year follow-up study.

    PubMed

    Çalışkan, M K; Tekin, U; Kaval, M E; Solmaz, M C

    2016-03-01

    To evaluate the influence of various predictors on the healing outcome 2-6 years after apical microsurgery (AMS) using MTA as the root-end filling material. A total of 90 anterior teeth with asymptomatic persistent periradicular periodontitis of strictly endodontic origin that failed after either nonsurgical or surgical treatment were included. Surgery was completed under local anaesthesia using a standardized clinical protocol. Clinical and radiographic measures as well as the follow-up period were used to determine the healing outcome. For statistical analysis of the predictors, the outcome was dichotomized into healed cases and nonhealed cases. Odds ratios were calculated, and Pearson chi-square or Fisher's exact tests were used to analyse the data. Clinical and radiographic assessment of AMS revealed that 80% were healed, 14.4% were nonhealed, whilst 5.6% were judged to be uncertain. None of the various predictors investigated had a significant influence on the outcome of AMS. The results of this clinical study demonstrated that 80% of cases that received apical microsurgery healed when using MTA as the root-end filling material. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. Growth Optimization Studies to Develop InAs/GaInSb Superlattice Materials for Very Long Wavelength Infrared Detection (Postprint)

    DTIC Science & Technology

    2014-10-01

    AFRL-RX-WP-JA-2015-0188 GROWTH OPTIMIZATION STUDIES TO DEVELOP INAS/GAINSB SUPERLATTICE MATERIALS FOR VERY LONG WAVELENGTH INFRARED...Interim 3. DATES COVERED (From – To) 17 January 2013 – 28 September 2014 4. TITLE AND SUBTITLE GROWTH OPTIMIZATION STUDIES TO DEVELOP INAS/GAINSB...AVAILABILITY STATEMENT Approved for public release; distribution unlimited. This report contains color. 13. SUPPLEMENTARY NOTES PA Case Number: 88ABW

  13. Short-term hot-hardness characteristics of five case hardened steels

    NASA Technical Reports Server (NTRS)

    Anderson, N. E.; Zaretsky, E. V.

    1975-01-01

    Short-term hot-hardness studies were performed with carburized and hardened AISI 8620, CBS 1000, CBS 1000M, CBS 600, and Vasco X-2 steels. Case and core hardness measurements were made at temperatures from 294 to 811 K (70 to 1000 F). The data were compared with data for high-speed tool steels and AISI 52100. The materials tested can be ranked as follows in order of decreasing hot-hardness retention: (1) Vasco X-2; equivalent to through-hardened tool steels up to 644 K (700 F) above which Vasco X-2 is inferior; (2) CBS 1000, (3) CBS 1000M; (4) CBS 6000; better hardness retention at elevated temperatures than through-hardened AISI 52100; and (5) AISI 8620. For the carburized steels, the change in hardness with temperature of the case and core are similar for a given material. The short-term hot hardness of these materials can be predicted with + or - 1 point Rockwell C.

  14. A Case Study on Content Based Instruction for Primary School Children

    ERIC Educational Resources Information Center

    Hidalgo Dávila, Helda Alicia; Caucedo Vela, Magda Lucy

    2011-01-01

    Teaching English at the primary school level is a challenge in countries such as Colombia where children study this language for only one hour a week in most institutions, and in the best of cases for 3 hours a week. Most of the public schools do not have enough and/or adequate English materials at their disposal for students to work with;…

  15. Computer-Assisted Learning in UK Engineering Degree Programmes: Lessons Learned from an Extensive Case Study Programme

    ERIC Educational Resources Information Center

    Rothberg, S. J.; Lamb, F. M.; Willis, L.

    2006-01-01

    This paper gives a synopsis of an extensive programme of case studies on real uses of computer-assisted learning (CAL) materials within UK engineering degree programmes. The programme was conducted between 2000 and 2003 and followed a questionnaire-based survey looking at CAL use in the UK and in Australia. The synopsis reveals a number of key…

  16. A case-study of landfill minimization and material recovery via waste co-gasification in a new waste management scheme.

    PubMed

    Tanigaki, Nobuhiro; Ishida, Yoshihiro; Osada, Morihiro

    2015-03-01

    This study evaluates municipal solid waste co-gasification technology and a new solid waste management scheme, which can minimize final landfill amounts and maximize material recycled from waste. This new scheme is considered for a region where bottom ash and incombustibles are landfilled or not allowed to be recycled due to their toxic heavy metal concentration. Waste is processed with incombustible residues and an incineration bottom ash discharged from existent conventional incinerators, using a gasification and melting technology (the Direct Melting System). The inert materials, contained in municipal solid waste, incombustibles and bottom ash, are recycled as slag and metal in this process as well as energy recovery. Based on this new waste management scheme with a co-gasification system, a case study of municipal solid waste co-gasification was evaluated and compared with other technical solutions, such as conventional incineration, incineration with an ash melting facility under certain boundary conditions. From a technical point of view, co-gasification produced high quality slag with few harmful heavy metals, which was recycled completely without requiring any further post-treatment such as aging. As a consequence, the co-gasification system had an economical advantage over other systems because of its material recovery and minimization of the final landfill amount. Sensitivity analyses of landfill cost, power price and inert materials in waste were also conducted. The higher the landfill costs, the greater the advantage of the co-gasification system has. The co-gasification was beneficial for landfill cost in the range of 80 Euro per ton or more. Higher power prices led to lower operation cost in each case. The inert contents in processed waste had a significant influence on the operating cost. These results indicate that co-gasification of bottom ash and incombustibles with municipal solid waste contributes to minimizing the final landfill amount and has great possibilities maximizing material recovery and energy recovery from waste. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Analytic Thermoelectric Couple Modeling: Variable Material Properties and Transient Operation

    NASA Technical Reports Server (NTRS)

    Mackey, Jonathan A.; Sehirlioglu, Alp; Dynys, Fred

    2015-01-01

    To gain a deeper understanding of the operation of a thermoelectric couple a set of analytic solutions have been derived for a variable material property couple and a transient couple. Using an analytic approach, as opposed to commonly used numerical techniques, results in a set of useful design guidelines. These guidelines can serve as useful starting conditions for further numerical studies, or can serve as design rules for lab built couples. The analytic modeling considers two cases and accounts for 1) material properties which vary with temperature and 2) transient operation of a couple. The variable material property case was handled by means of an asymptotic expansion, which allows for insight into the influence of temperature dependence on different material properties. The variable property work demonstrated the important fact that materials with identical average Figure of Merits can lead to different conversion efficiencies due to temperature dependence of the properties. The transient couple was investigated through a Greens function approach; several transient boundary conditions were investigated. The transient work introduces several new design considerations which are not captured by the classic steady state analysis. The work helps to assist in designing couples for optimal performance, and also helps assist in material selection.

  18. Transcatheter Arterial Embolization for Primary Postpartum Hemorrhage: Predictive Factors of Need for Embolic Material Conversion of Gelatin Sponge Particles to N-Butyl Cyanoacrylate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tanahashi, Yukichi; Goshima, Satoshi, E-mail: gossy@par.odn.ne.jp; Kondo, Hiroshi

    PurposeTo identify predictive factors for embolic material conversion to N-butyl cyanoacrylate (NBCA) for the treatment of primary postpartum hemorrhage (PPH) after failed transcatheter arterial embolization (TAE) using gelatin sponge (GS).Materials and MethodsInstitutional review board approval was obtained. We retrospectively studied 62 consecutive women with primary PPH who underwent TAE between January 2006 and March 2015. Five of them were excluded for the following: cardiopulmonary arrest at arrival (n = 1), uterine inversion (n = 1), and hysterectomy after TAE (n = 3). Remaining 57 women (age range, 21–43 years; mean, 32.6 years) comprised study population. TAE was initially performed using GS in all cases andmore » then converted to NBCA after two embolizations using GS with persistent hemodynamic instability or vaginal bleeding. The patients’ background, uterine height, vital signs, laboratory tests, disseminated intravascular coagulation score, and details of procedure were reviewed. Univariate and multivariate analyses were performed to determine factors related to embolic material conversion.ResultsTechnical success rate was 100%. Fourteen patients (25%) needed embolic material conversion to NBCA. Univariate analysis showed that uterine height, systolic blood pressure (sBP), and hemoglobin level were significantly related to embolic material conversion to NBCA (P = 0.029, 0.030, and 0.042). Logistic regression analysis showed that uterine height (odds ratio, 1.37; P = 0.025) and sBP (odds ratio, 0.96; P = 0.003) were associated with embolic material conversion to NBCA.ConclusionUterine height and sBP can be predictive factors for embolic material conversion to NBCA for the treatment of PPH.Level of EvidenceLevel 4, Case Control Study.« less

  19. Local structure studies of materials using pair distribution function analysis

    NASA Astrophysics Data System (ADS)

    Peterson, Joseph W.

    A collection of pair distribution function studies on various materials is presented in this dissertation. In each case, local structure information of interest pushes the current limits of what these studies can accomplish. The goal is to provide insight into the individual material behaviors as well as to investigate ways to expand the current limits of PDF analysis. Where possible, I provide a framework for how PDF analysis might be applied to a wider set of material phenomena. Throughout the dissertation, I discuss 0 the capabilities of the PDF method to provide information pertaining to a material's structure and properties, ii) current limitations in the conventional approach to PDF analysis, iii) possible solutions to overcome certain limitations in PDF analysis, and iv) suggestions for future work to expand and improve the capabilities PDF analysis.

  20. A Case Study Of Organic Dirac Materials -

    NASA Astrophysics Data System (ADS)

    Commeau, Benjamin; Geilhufe, Matthias; Fernando, Gayanath; Balatsky, Alexander

    Dirac Materials are characterized by linear band crossings within the electronic band structure. Most research of Dirac materials has been dedicated towards inorganic materials, e.g., binary chalcogenides as toplogical insulators, the Weyl semimetal TaAs or graphene. The purpose of this study is to investigate the formation of Dirac points in organic materials under pressure and mechanical strain. We study multiple structural phases of the organic charge-transfer salt (BEDT-TTF)2I3. We numerically calculate the relaxed band structure near the Fermi level along different k-space directions. Once the relaxed ion structure is obtained, we pick different cell parameters to shrink and investigate the changes in the band structure. We discuss band structure degeneracies protected by crystalline and other symmetries, if any. Quantum Espresso and VASP codes were used to calculate and validate our results.

  1. Assessing environmental risks for high intensity agriculture using the material flow analysis method--a case study of the Dongting Lake basin in South Central China.

    PubMed

    Yin, Guanyi; Liu, Liming; Yuan, Chengcheng

    2015-07-01

    This study primarily examined the assessment of environmental risk in high intensity agricultural areas. Dongting Lake basin was taken as a case study, which is one of the major grain producing areas in China. Using data obtained from 1989 to 2012, we applied Material Flow Analysis (MFA) to show the material consumption, pollutant output and production storage in the agricultural-environmental system and assessed the environmental risk index on the basis of the MFA results. The results predicted that the status of the environmental quality of the Dongting Lake area is unsatisfactory for the foreseeable future. The direct material input (DMI) declined by 13.9%, the domestic processed output (DPO) increased by 28.21%, the intensity of material consumption (IMC) decreased by 36.7%, the intensity of material discharge (IMD) increased by 10%, the material productivity (MP) increased by 27 times, the environmental efficiency (EE) increased by 15.31 times, and the material storage (PAS) increased by 0.23%. The DMI and DPO was higher at rural places on the edge of cities, whereas the risk of urban agriculture has arisen due to the higher increasing rate of DMI and DPO in cities compared with the counties. The composite environmental risk index increased from 0.33 to 0.96, indicating that the total environmental risk changed gradually but seriously during the 24 years assessed. The driving factors that affect environmental risk in high intensity agriculture can be divided into five classes: social, economic, human, natural and disruptive incidents. This study discussed a number of effective measures for protecting the environment while ensuring food production yields. Additional research in other areas and certain improvements of this method in future studies may be necessary to develop a more effective method of managing and controlling agricultural-environmental interactions.

  2. Chromosomal Gains at 9q Characterize Enteropathy-Type T-Cell Lymphoma

    PubMed Central

    Zettl, Andreas; Ott, German; Makulik, Angela; Katzenberger, Tiemo; Starostik, Petr; Eichler, Thorsten; Puppe, Bernhard; Bentz, Martin; Müller-Hermelink, Hans Konrad; Chott, Andreas

    2002-01-01

    Genetic alterations in enteropathy-type T-cell lymphoma (ETL) are unknown so far. In this series, 38 cases of ETL were analyzed by comparative genomic hybridization (CGH). CGH revealed chromosomal imbalances in 87% of cases analyzed, with recurrent gains of genetic material involving chromosomes 9q (in 58% of cases), 7q (24%), 5q (18%), and 1q (16%). Recurrent losses of genetic material occurred on chromosomes 8p and 13q (24% each), and 9p (18%). In this first systematic genetic study on ETL, chromosomal gains on 9q (minimal overlapping region 9q33-q34) were found to be highly characteristic of ETL. Fluorescence in situ hybridization analysis on four cases of ETL, using a probe for 9q34, indicated frequent and multiple gains of chromosomal material at 9q34 (up to nine signals per case). Among 16 patients with ETL who survived initial disease presentation, patients with more than three chromosomal gains or losses (n = 11) followed a worse clinical course than those with three or less imbalances (n = 5). The observation of similar genetic alterations in ETL and in primary gastric (n = 4) and colonic (n = 1) T-cell lymphoma, not otherwise specified, is suggestive of a genetic relationship of gastrointestinal T-cell lymphomas at either localization. PMID:12414511

  3. The implementation of case study with module-assisted to improve students' understanding on phytochemistry course

    NASA Astrophysics Data System (ADS)

    Julianto, Tatang Shabur; Fitriastuti, Dhina; Diniaty, Artina; Fauzi'ah, Lina; Arlianty, Widinda Normalia; Febriana, Beta Wulan; Muhaimin

    2017-12-01

    Phytochemistry is one of the course in Chemistry Department's curriculum which discusses about biosynthetic path of secondary metabolite compound in a plant, classification of secondary metabolite compound, isolation technique, and identification analysis. This course is expected to be able to bridge the generations of a nation that has expertise in managing the natural resources of Indonesian plants. In this research, it was evaluated the implementation of case study learning method towards students' understanding on phytochemistry course. The learning processes were conducted in 2 cycles i.e. before and after midterm. The first seven themes of materials before midterm were learned with case study method and the next seven themes of materials were studied with the same method with the module-assisted. The results showed that there was enhancement of students' understanding in class D that were obtained from comparison of midterm and final test. Contrarily, the students of class C have no significant enhancement. In addition, it was predicted that understanding enhancement was strongly influenced by the life skills and the motivation of students especially the academic skills aspect.

  4. Core curriculum illustration: rib fractures.

    PubMed

    Dunham, Gregor M; Perez-Girbes, Alexandre; Linnau, Ken F

    2017-06-01

    This is the 24th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at http://www.aseronline.org/curriculum/toc.htm .

  5. Analysis of the frequency and nature of hyaline ring granulomas in inflammatory odontogenic cysts.

    PubMed

    Henriques, A C G; Pereira, J S; Nonaka, C F W; Freitas, R A; Pinto, L P; Miguel, M C C

    2013-01-01

    To determine the prevalence of hyaline ring granulomas (HRGs) in a large case series of inflammatory odontogenic cysts, and to investigate the nature of these structures. All records from the patients diagnosed with inflammatory odontogenic cysts between January 1970 and April 2009 were reviewed. Histologic sections were evaluated by light microscopy and cases with HRGs for which sufficient biological material was available were submitted to histochemical analysis (Masson's trichrome) and immunohistochemistry (CD34, CD68 and collagen IV). Twenty-two (3.3%) of the 661 cases of inflammatory odontogenic cysts diagnosed during the study period presented HRGs. The relative frequency of HRGs was higher amongst residual radicular cysts (6.1%), followed by paradental cysts (5.6%) and radicular cysts (3.0%). HRGs appeared as roughly circular homogeneous/fibrillar masses in 14 (63.6%) cases and as round structures enclosing amorphous material in 3 (13.6%) cases. Most (77.8%) roughly circular homogeneous/fibrillar masses were positive for collagen, whereas all (100.0%) round structures enclosing amorphous material were negative for this protein. Immunohistochemistry showed that most mononucleated cells and all multinucleated giant cells were positive for CD68, but negative for CD34, in all cases. In addition, collagen IV immunostaining was negative in amorphous structures and weakly positive in homogeneous/fibrillar masses. The present results suggest a very low frequency of HRGs in inflammatory odontogenic cysts and support the hypothesis that these structures arise from the implantation of foreign material, most likely food particles of plant or vegetable origin. The diverse microscopic features of HRG possibly represent different developmental stages of this structure. © 2012 International Endodontic Journal.

  6. Improving ethical knowledge and sensemaking from cases through elaborative interrogation and outcome valence.

    PubMed

    Johnson, James F; Bagdasarov, Zhanna; MacDougall, Alexandra E; Steele, Logan; Connelly, Shane; Devenport, Lynn D; Mumford, Michael D

    2014-01-01

    The case-based approach to learning is popular among many applied fields. However, results of case-based education vary widely on case content and case presentation. This study examined two aspects of case-based education-outcome valence and case elaboration methods-in a two-day case-based Responsible Conduct of Research (RCR) ethics education program. Results suggest that outcome information is an integral part of a quality case. Furthermore, valence consistent outcomes may have certain advantages over mixed valence outcome information. Finally, students enjoy and excel working with case material, and the use of elaborative interrogation techniques can significantly improve internally-focused ethical sensemaking strategies associated with personal biases, constraints, and emotions.

  7. Homicides with corpse dismemberment in the material collected by the Department of Forensic Medicine, Krakow, Poland.

    PubMed

    Konopka, Tomasz; Bolechała, Filip; Strona, Marcin; Kopacz, Paweł

    2016-01-01

    Aim of the study: To determine the circumstances which can be useful for offenders profiling in homicide cases with victim's body dismemberment. Material and methods: Study of all homicide cases with victim's corpse dismemberment examined in Krakow Department of Forensic Medicine over the last 50 years. Results: Within the past 50 years, a total number of 30 cases of homicides with dismembered bodies were examined in Krakow. 22 cases represent defensive mutilations performed by offender, 3 cases can be classified as offensive muti-lations and 3 cases represent aggressive mutilations - decapitation as a method of committing homicide. In this period the only 1 case of necrophilic mutilations was examined, when the body was dismembered without murder. In most cases the background of homicide was the family conflict, 6 was cause of mental illness of perpetrator and in 3 was sexual motive. Only in 3 cases (from 25 when the offender was known) perpetrator kill a stranger. In the other the offender belonged to the family or friends of the victim. In all cases where the perpetrator was determined, homicide and dismemberment was performed in his place of residence. The findings of the Police investigations indicate that in most cases homicides were not planned, occurred under the influence of emotion, only two have been previously scheduled. Conclusions: Homicides with corpses dismemberment usually are committed by offenders who is in close relationship with victim (family or friend). Dismemberment is almost always performed in the same place as murder - home of perpetrator. This type of homicide usually is not planned.

  8. Sustainability in a Differential Equations Course: A Case Study of Easter Island

    ERIC Educational Resources Information Center

    Koss, Lorelei

    2011-01-01

    Easter Island is a fascinating example of resource depletion and population collapse, and its relatively short period of human habitation combined with its isolation lends itself well to investigation by students in a first-semester ordinary differential equations course. This article describes curricular materials for a semester-long case study…

  9. Extravasation of contrast material from vascular ectasia of the cecum detected with /sup 99m/Tc-pertechnetate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tavormina, A.; Mousavi, A.; Gordon, D.H.

    A case of vascular ectasia of the cecum is presented. The isotopic pattern did not differ from that of Meckel's diverticulum. The authors suggest that studies with /sup 99m/Tc may be helpful in screening for areas of pathology in cases of lower gastrointestinal bleeding.

  10. Developing Self-Regulated Learners through Collaborative Online Case Discussion in Educational Psychology

    ERIC Educational Resources Information Center

    Willems, Patricia P.; Gonzalez-DeHass, Alyssa

    2015-01-01

    Case study instruction is characterized by centering instruction around the use of hypothetical classroom dilemmas. It uses descriptive stories and invites students to discuss application of course material as they engage in hypothetical classroom problem-solving and teacher decision-making. Teaching is a complex profession that requires high…

  11. Utilizing the Peer Group Method with Case Studies to Teach Pharmacokinetics.

    ERIC Educational Resources Information Center

    Sims, Pamela J.

    1994-01-01

    A pharmacy school large-group (110 students) course in pharmacokinetics was designed to incorporate small-group team-based problem solving. The method allows students to learn material through traditional lecture, research the topic further, discuss the information gained, and apply the learning to specific cases in a manner that promotes…

  12. A Case Example of Insect Gymnastics: How Is Non-Euclidean Geometry Learned?

    ERIC Educational Resources Information Center

    Junius, Premalatha

    2008-01-01

    The focus of the article is on the complex cognitive process involved in learning the concept of "straightness" in Non-Euclidean geometry. Learning new material is viewed through a conflict resolution framework, as a student questions familiar assumptions understood in Euclidean geometry. A case study reveals how mathematization of the straight…

  13. Impacts of Vehicle Weight Reduction via Material Substitution on Life-Cycle Greenhouse Gas Emissions.

    PubMed

    Kelly, Jarod C; Sullivan, John L; Burnham, Andrew; Elgowainy, Amgad

    2015-10-20

    This study examines the vehicle-cycle and vehicle total life-cycle impacts of substituting lightweight materials into vehicles. We determine part-based greenhouse gas (GHG) emission ratios by collecting material substitution data and evaluating that alongside known mass-based GHG ratios (using and updating Argonne National Laboratory's GREET model) associated with material pair substitutions. Several vehicle parts are lightweighted via material substitution, using substitution ratios from a U.S. Department of Energy report, to determine GHG emissions. We then examine fuel-cycle GHG reductions from lightweighting. The fuel reduction value methodology is applied using FRV estimates of 0.15-0.25, and 0.25-0.5 L/(100km·100 kg), with and without powertrain adjustments, respectively. GHG breakeven values are derived for both driving distance and material substitution ratio. While material substitution can reduce vehicle weight, it often increases vehicle-cycle GHGs. It is likely that replacing steel (the dominant vehicle material) with wrought aluminum, carbon fiber reinforced plastic (CRFP), or magnesium will increase vehicle-cycle GHGs. However, lifetime fuel economy benefits often outweigh the vehicle-cycle, resulting in a net total life-cycle GHG benefit. This is the case for steel replaced by wrought aluminum in all assumed cases, and for CFRP and magnesium except for high substitution ratio and low FRV.

  14. The Credit Business. Instructor's Guide [and] Student Materials. Business Issues in the Classroom. Revised.

    ERIC Educational Resources Information Center

    Maxey, Phyllis F.; And Others

    One of a series of units on business issues designed for secondary school students, this packet examines the responsibilities of the lender and consumer in the credit business. Teacher and student materials are provided in separate sections. The teacher's guide presents five detailed lesson plans, each focusing on a credit case study; discussion…

  15. Case Studies in Critical Ecoliteracy: A Curriculum for Analyzing the Social Foundations of Environmental Problems

    ERIC Educational Resources Information Center

    Turner, Rita; Donnelly, Ryan

    2013-01-01

    This article outlines the features and application of a set of model curriculum materials that utilize eco-democratic principles and humanities-based content to cultivate critical analysis of the cultural foundations of socio-environmental problems. We first describe the goals and components of the materials, then discuss results of their use in…

  16. Delivering and Assessing Learning Material through Gquest: A Case Study on Patient Education

    ERIC Educational Resources Information Center

    Lanzola, Giordano; Ginardi, Germana; Russo, Paola; Quaglini, Silvana

    2014-01-01

    Gquest is a mobile platform for administering interviewing and learning material. It relies on a model that supports adaptivity in the dialog with its users and enforces consistency rules to constrain their input. Gquest downloads its modules over the air making them available to the users, then a synchronization engine collects any input provided…

  17. Supervisor's Manual: Great Falls Transition Project, a Cooperative Model for Least Restrictive Employment.

    ERIC Educational Resources Information Center

    White, Stephen; And Others

    The manual is intended to provide employment supervisors with skills to enable them to motivate and provide any needed support to workers with disabilities. The material is organized into seven short sessions with most of the material consisting of basic principles for communicating and instructing persons with disabilities and case study problems…

  18. Detection of diisocyanates in nesting material associated with mortality in pigeon chicks.

    PubMed

    Mukai, Motoko; Woods, Leslie W; Stump, Samuel; Ebel, Joseph G; Levitt, Ariana S; Frey, Margaret W; Smith, Jeanne; Uzal, Francisco A; Poppenga, Robert H; Puschner, Birgit

    2014-03-01

    Diisocyanates, commonly used in the production of polyurethane foams, paints, elastomers, varnishes, and coatings, are considered among the most hazardous inhalation toxicants. The present report describes 2 unusual cases of mortality in pigeon chicks associated with nesting material contaminated by diisocyanates. Case 1 was submitted by a racing pigeon breeder who had lost all the hatchlings (n = 125) following replacement of the nesting material with a different lot. All adult birds appeared healthy, and hatchability was not significantly affected, but hatchlings became lethargic and dyspneic after a day of hatch. At necropsy, dark wet lungs were found in the hatchlings. Case 2 was submitted by a show-roller pigeon breeder. In this case, the owner reported lower hatchability, and all hatchlings (approximately 100) died within 2 days of hatching with clinical signs similar to the first case. Necropsy did not reveal any significant findings. For both cases, nesting materials were screened for toxic compounds using gas chromatography-mass spectrometry. Toluene-2,4-diisocyanate (approximately 190-290 ppm) and 4,4'-methylene diphenyl diisocyanate (unquantified) were detected in the nesting pads. While there is very limited information on toxicosis in birds, there are reports of inhalant exposure of diisocyanates causing pulmonary edema and death in various mammalian species. Although cause-effect relationship of mortality and the nesting material was not established in the present cases, the presence of toxic compounds in the nesting materials is a cause for concern. Further investigation is needed to determine the prevalence and toxicity of diisocyanates-contaminated nesting material in avian species.

  19. Forecasting waste compositions: A case study on plastic waste of electronic display housings.

    PubMed

    Peeters, Jef R; Vanegas, Paul; Kellens, Karel; Wang, Feng; Huisman, Jaco; Dewulf, Wim; Duflou, Joost R

    2015-12-01

    Because of the rapid succession of technological developments, the architecture and material composition of many products used in daily life have drastically changed over the last decades. As a result, well-adjusted recycling technologies need to be developed and installed to cope with these evolutions. This is essential to guarantee continued access to materials and to reduce the ecological impact of our material consumption. However, limited information is currently available on the material composition of arising waste streams and even less on how these waste streams will evolve. Therefore, this paper presents a methodology to forecast trends in the material composition of waste streams. To demonstrate the applicability and value of the proposed methodology, it is applied to forecast the evolution of plastic housing waste from flat panel display (FPD) TVs, FPD monitors, cathode ray tube (CRT) TVs and CRT monitors. The results of the presented forecasts indicate that a wide variety of plastic types and additives, such as flame retardants, are found in housings of similar products. The presented case study demonstrates that the proposed methodology allows the identification of trends in the evolution of the material composition of waste streams. In addition, it is demonstrated that the recycling sector will need to adapt its processes to deal with the increasing complexity of plastics of end-of-life electronic displays while respecting relevant directives. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. The Use of Soil in Criminal Investigations

    NASA Astrophysics Data System (ADS)

    Dawson, Lorna; Fitzpatrick, Robert

    2013-04-01

    Forensic soil science, as a newly developed discipline of soil science, has matured to the extent that well-defined questions and successful crime scene investigations are being addressed in increasingly refined ways to assist law enforcement agencies. Soils, rocks, regolith, minerals and man-made mineral particles such as bricks (i.e. referred to "human-made" soil materials) are being used in specialised forensic investigations to associate/disassociate a sample taken from an item, such as shoes, clothing, shovel or vehicle, with a specific location. The majority of forensic cases involving soil materials are usually overwhelmingly complex, and the challenges of associating relevant information from one source with another, often requires the use and development of sophisticated field and laboratory methods. Through examples from case studies, this presentation will demonstrate how advanced field and laboratory approaches have been critical in developing coherent, predictive, soil models, from landscape to microscopic scales, to help contribute to soil-based criminal investigations in both Australia and Scotland. To demonstrate the critical importance of soil materials in forensic investigations, the following 2 case studies, which tackle difficult problems at a range of scales involving highly complex issues, will be presented: •The use of soil evidence to help solve a double murder case. This investigation used morphological, chemical, physical and mineralogical properties to identify similarities between soil-regolith found on a shovel taken from the suspect's vehicle and wetland soil-regolith subsequently located in the bottom of a quarry (Fitzpatrick and Raven, 2012). •The use of soil and related material to help search and to provide evidence in a murder case. This investigation used soil mineralogical and organic properties to identify similarities between sand found on a shovel and sand subsequently located at a beach. Results illustrate the benefit of using a complementary approach and consideration of the two way transfer of materials (Dawson and Hillier, 2010). References Fitzpatrick R.W. and Raven M.D. (2012) How Pedology and mineralogy helped solve a double murder case: Using forensics to inspire future generations of soil scientists. Soil Horizons. 53 (5) doi:10.2136/sh12-05-0016. Dawson, L.A. Hillier, S. (2010) Measurement of soil characteristics for forensic applications. Surface and Interface Analysis, 42, 363-377.

  1. Study Of Pre-Shaped Membrane Mirrors And Electrostatic Mirrors With Nonlinear-Optical Correction

    DTIC Science & Technology

    2002-01-01

    mirrors have been manufactured of glass-like material Zerodur with very low coefficient of linear expansion. They have a more light cellular construction...primary and flat secondary mirrors are both segmented ones. In the case of the primary mirror made of traditional materials such as Zerodur or fused...FINAL REPORT ISTC Project #2103p “Study of Pre-Shaped Membrane Mirrors and Electrostatic Mirrors with Nonlinear-Optical Correction” Manager

  2. Terrorism and hazardous material trucking: promoting perceived collective efficacy for terrorism prevention.

    PubMed

    James, Keith

    2008-01-01

    Hazardous-material trucking has recently been identified as an area of high potential risk for terrorism. Some recent theory and case study papers have argued for the importance of collective efficacy to disaster-response, terrorism prevention, and other rare-but-risky events. Therefore, a study based on the collective efficacy literature was done to test an intervention for increasing perceived collective efficacy for terrorism prevention among Canadian hazardous-material truck drivers. Results supported the impact of the intervention in increasing perceived efficacy for terrorism prevention. Implications for theory, research, and application are discussed.

  3. Computer model for refinery operations with emphasis on jet fuel production. Volume 1: Program description

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    A FORTRAN computer program is described for predicting the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.

  4. Computer model for refinery operations with emphasis on jet fuel production. Volume 3: Detailed systems and programming documentation

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    The FORTRAN computing program predicts flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuels of varying end point and hydrogen content specifications. The program has a provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.

  5. Heterologous, Fresh, Human Donor Sclera as Patch Graft Material in Glaucoma Drainage Device Surgery.

    PubMed

    Tsoukanas, Dimitrios; Xanthopoulou, Paraskevi; Charonis, Alexandros C; Theodossiadis, Panagiotis; Kopsinis, Gerasimos; Filippopoulos, Theodoros

    2016-07-01

    To determine the safety and efficacy of fresh, human sclera allografts as a patch graft material in glaucoma drainage device (GDD) surgery. Retrospective, noncomparative, interventional, consecutive case series. All GDD cases operated between 2008 and 2013 in which fresh human corneoscleral rims were used immediately after the central corneal button was used for penetrating or endothelial keratoplasty. Surgery was performed by 2 surgeons at 2 facilities. The Ahmed Glaucoma Valve (FP-7) was used exclusively in this cohort. Sixty-four eyes of 60 patients were identified; demographic data were recorded along with intraocular pressure (IOP), medication requirements, visual acuity, complications, and subsequent interventions. Incidence of complications. IOP and medication requirements at the last follow-up. Quilified success utilizing Tube Versus Trabeculectomy study criteria. The mean age of the cohort was 66.2±19.1 years; the average preoperative IOP was 33.2±11.1 mm Hg on 4.2±1.3 IOP-lowering agents before GDD surgery. IOP decreased significantly to 14.1±4.7 mm Hg (P<0.001) on 1.6±1.2 IOP-lowering agents (P<0.001) after an average follow-up of 18.2±15.4 months. There were no cases of early or late blebitis or endophthalmitis, and there was 1 case of conjunctival erosion and tube/plate exposure (1.6%) occurring 30 days after surgery. Qualified success was estimated as 90.5% and 81% at 1 and 2 years, respectively, using Tube Versus Trabeculectomy study criteria. Heterologous, fresh, human donor sclera appears to be a safe material for GDD tube coverage. It provides a cost-efficient alternative compared with traditional patch graft materials associated with a low risk of pathogen transmission.

  6. DOE Zero Energy Ready Home Case Study: Amaris Custom Homes, St.Paul, Minnesota; DOE Zero Energy Ready Home Case Study, Energy Efficiency & Renewable Energy (EERE)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2015-06-01

    For this project Amaris worked with U.S. Department of Energy (DOE) team, NorthernSTAR Building America Partnership, to approach zero energy in Minnesota's cold climate using reasonable, cost-effective, and replicable construction materials and practices. The result is a passive solar, super-efficient 3542-ft2 walkout rambler with all the creature comforts.

  7. Economic Education Experiences of Enterprising Teachers, Volume 15. A Report Developed from the 1976-77 Entries in the International Paper Company Foundation Awards Program for the Teaching of Economics.

    ERIC Educational Resources Information Center

    Dawson, George G., Ed.

    Twenty award winning, teacher-developed programs, projects, courses, and materials in economic education are presented. These case study projects are designed to be used with kindergarten through college students. The case studies are organized by grade level into five chapters. Chapter I suggests ways to teach economic concepts to educable…

  8. Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

    PubMed

    Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

    2001-01-01

    Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

  9. Integrated approaches for reducing sample size for measurements of trace elemental impurities in plutonium by ICP-OES and ICP-MS

    DOE PAGES

    Xu, Ning; Chamberlin, Rebecca M.; Thompson, Pam; ...

    2017-10-07

    This study has demonstrated that bulk plutonium chemical analysis can be performed at small scales (\\50 mg material) through three case studies. Analytical methods were developed for ICP-OES and ICP-MS instruments to measure trace impurities and gallium content in plutonium metals with comparable or improved detection limits, measurement accuracy and precision. In two case studies, the sample size has been reduced by 109, and in the third case study, by as much as 50009, so that the plutonium chemical analysis can be performed in a facility rated for lower-hazard and lower-security operations.

  10. Integrated approaches for reducing sample size for measurements of trace elemental impurities in plutonium by ICP-OES and ICP-MS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, Ning; Chamberlin, Rebecca M.; Thompson, Pam

    This study has demonstrated that bulk plutonium chemical analysis can be performed at small scales (\\50 mg material) through three case studies. Analytical methods were developed for ICP-OES and ICP-MS instruments to measure trace impurities and gallium content in plutonium metals with comparable or improved detection limits, measurement accuracy and precision. In two case studies, the sample size has been reduced by 109, and in the third case study, by as much as 50009, so that the plutonium chemical analysis can be performed in a facility rated for lower-hazard and lower-security operations.

  11. Single Center Experience with the AngioVac Aspiration System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salsamendi, Jason, E-mail: jsalsamendi@med.miami.edu; Doshi, Mehul, E-mail: mdoshi@med.miami.edu; Bhatia, Shivank, E-mail: sbhatia1@med.miami.edu

    2015-08-15

    PurposeThe AngioVac catheter system is a mechanical suction device designed for removal of intravascular material using extracorporeal veno-venous bypass circuit. The purpose of this study is to present the outcomes in patients treated with the AngioVac aspiration system and to discuss its efficacy in different vascular beds.Materials and MethodsA retrospectively review was performed of seven patients treated with AngioVac between October 2013 and December 2014. In 6/7 cases, the AngioVac cannula was inserted percutaneously and the patient was placed on veno-venous bypass. In one of the cases, the cannula was inserted directly into the Fontan circuit after sternotomy and themore » patient was maintained on cardiopulmonary bypass. Thrombus location included iliocaval (2), SVC (1), pulmonary arteries (1), Fontan circuit and Glenn shunt with pulmonary artery extension (1), right atrium (1), and IVC with renal vein extension (1).ResultsThe majority of thrombus (50–95 %) was removed in 5/7 cases, and partial thrombus removal (<50 %) was confirmed in 2/7 cases. Mean follow-up was 205 days (range 64–403 days). All patients were alive at latest follow-up. Minor complications included three neck hematomas in two total patients. No major complications occurred.ConclusionAngioVac is a useful tool for acute thrombus removal in the large vessels. The setup and substantial cost may limit its application in straightforward cases. More studies are needed to establish the utility of AngioVac in treatment of intravascular and intracardiac material.« less

  12. The use of nipah leaves (Nypa fruticans) as an environmentally friendly roofing material

    NASA Astrophysics Data System (ADS)

    Umar, Muhammad Zakaria; Faslih, Arman; Arsyad, Muhammad; Ikhsan, Ainussalbi Al; Umar, Mazhfia

    2017-09-01

    An environmentally friendly building is a building that cares for the environment. The use of building materials from plants are very beneficial to maintain the climatic conditions of space and one proper example is the roof made from palm leaves. Petoaha Village, located in the District of Abeli, Kendari Municipality has craftsmen specified in creating roof from palm leaves. The purpose of this study to analyze and identify the instruments of labor, materials, and how to create a roof of palm leaves in the Petoaha Village. This research applies a qualitative case study approach. The result shows that the roof of palm leaves is categorized as an environmentally friendly roofing material due to simple working tools, vegetative based material, man power use and preservation process through immersion in sea water.

  13. Etude theorique et experimentale de la correlation entre la resistance aux chocs thermiques et aux chocs mecaniques des materiaux refractaires utilises dans les fours de traitement de l'aluminium

    NASA Astrophysics Data System (ADS)

    Sebbani, Mohamed Jamal Eddine

    2001-07-01

    This work is a theoretical and experimental study of the correlation between the resistance to thermal shock and mechanical shock of refractory materials. The study of thermal shock showed that the Bahr and Hasselman approaches are alike and that they can be combined into a single, more general approach. This generalisation allowed the division of the theoretical models into two groups: the Hasselman model and the Harmuth model. However, neither of these approaches can predict the behaviour of all refractory materials submitted to thermal shock. Therefore, the generalisation of the Hasselman approach is more appropriate for more dense materials while the Hartmuth approach is more appropriate for less dense materials. The influence of porosity on the energy of rupture helped to explain the behaviour of the less dense material. The absence of generalisation in this case allows those parameters that could be correlated with thermal shock resistance to be dependent on the type of refractory. The study of mechanical shock provided a better understanding of this mechanism. The work performed showed, theoretically and experimentally, that the resistance of the refractory materials could be correlated with the parameter s20 Egwof n-22 . This new parameter helped to explain the statistical correlation between the resistance to mechanical impact and the soxRst parameter established in earlier work. The sintering influence, which makes the refractories more resistant to this type of demand, notably by reducing the "n" coefficient, was shown. This part of the study allowed the establishment of equivalence between thermal fatigue and fatigue by mechanical impact. An evaluation of the correlation between the two mechanisms demonstrated, theoretically and experimentally, that the mechanical and thermal demands could only be exceptionally correlated. In the case of thermal shock, which are imposed deformation demands, it is the shorter cracks which are the most dangerous. However, in the case of mechanical shock, which is constraint imposed, it is the longer cracks that are the most harmful. (Abstract shortened by UMI.)

  14. Surface polaritons in grating composed of left-handed materials

    NASA Astrophysics Data System (ADS)

    Tiwari, D. C.; Premlal, P. L.; Chaturvedi, Vandana

    2018-01-01

    In this work, we developed a unique mathematical model to solve dispersion relation for surface polaritons (SPs) in artificial composite materials grating. Here, we have taken two types of materials for analysis. In the first case, the grating composed of epsilon-negative (ENG) material and air interface. In second case, grating composed of left-handed materials (LHMs) and ENG medium interface is considered. The dispersion curves of both p and s polarized SPs modes are obtained analytically. In the case of ENG grating and air interface, polaritons dispersion curves exist for p-polarization only, whereas for LHM grating and ENG medium interface, the polaritons dispersion curves for both p and s polarization are observed.

  15. Designing Biomimetic Materials from Marine Organisms.

    PubMed

    Nichols, William T

    2015-01-01

    Two biomimetic design approaches that apply biological solutions to engineering problems are discussed. In the first case, motivation comes from an engineering problem and the key challenge is to find analogous biological functions and map them into engineering materials. We illustrate with an example of water pollution remediation through appropriate design of a biomimetic sponge. In the second case, a biological function is already known and the challenge is to identify the appropriate engineering problem. We demonstrate the biological approach with marine diatoms that control energy and materials at their surface providing inspiration for a number of engineering applications. In both cases, it is essential to select materials and structures at the nanoscale to control energy and materials flows at interfaces.

  16. Synthesis and characterization of cathode, anode and electrolyte materials for rechargeable lithium batteries

    NASA Astrophysics Data System (ADS)

    Yang, Shoufeng

    Two new classes of cathode materials were studied: iron phosphate/sulfate materials and layered manganese oxides, both of which are low cost and had shown some potential. The first class of materials have poor conductivity and cyclability. I studied a number of methods for increasing the conductivity, and determined that grinding the material with carbon black was as effective as special in-situ coatings. The optimum carbon loading was determined to be between 6 and 15 wt%. Too much carbon reduces the volumetric energy density, whereas too little significantly increased cell polarization (reduced the rate of reaction). The kinetic and thermodynamic stability of LiFePO 4 was also studied and it was determined that over discharge protection will be needed as irreversible Li3PO4 can be formed at low potentials. A novel hydrothermal synthesis method was developed, but the significant level of Fe on the Li site reduces the reaction rate too much. In the case of the layered manganese oxide, cation substitution with Co and Ni is found to be effective in avoiding Jahn-Teller effects and improving electrochemistry. A wide range of tin compounds have been suggested as lithium storage media for advanced anode materials, as tin can store over 4 Li per Sn atom. Lithium hexafluorophosphate, LiPF6, is presently the salt of choice for LiCoO2 batteries, but it is expensive and dissolves some manganese compounds. The lithium bis(oxolato)borate (BOB) salt was recently reported, and I made a study of its use in cells with the LiFePO4 cathode and the tin anode. During its synthesis, it became clear that LiBOB is very reactive with many solvents, and these complexes were characterized to better understand this new material. In LiBOB the lithium is five coordinated, an unstable configuration for the lithium ion so that water and many other solvents rapidly react to make a six coordination. Only in the case of ethylene carbonate was the lithium found to be four coordinated. The LiBOB based electrolyte has a lower ionic conductivity than LiPF6, thus providing a poorer performance, while the capacity retention is improved. Further improvement of conductivity is still needed. Improved LiFePO4 cathode materials have been formed, the behavior of pure tin in the form of foil has been determined and will serve as the base case for future studies of tin based anodes, and the structure and electrochemical behavior of the new LIBOB electrolyte salt has been determined. (Abstract shortened by UMI.)

  17. The effect of crystal size on tunneling phenomena in luminescent nanodosimetric materials

    NASA Astrophysics Data System (ADS)

    Pagonis, Vasilis; Bernier, Shannon; Vieira, Francisco Marques dos Santos; Steele, Shane

    2017-12-01

    The study of luminescence signals from nanodosimetric materials is an active research area, due to the many possible practical applications of such materials. In several of these materials it has been shown that quantum tunneling is a dominant mechanism for recombination processes associated with luminescence phenomena. This paper examines the effect of crystal size on quantum tunneling phenomena in nanocrystals, based on the assumption of a random distribution of electrons and positive ions. The behavior of such random distributions is determined by three characteristic lengths: the radius of the crystal R, the tunneling length a, and the initial average distance 〈d〉 between electrons and positive ions (which is directly related to the density of charges in the material). Two different cases are examined, depending on the relative concentrations of electrons and ions. In the first case the concentration of electrons is assumed to be much smaller than the concentration of positive ions. Examination of a previously derived analytical equation demonstrates two different types of crystal size effects. When the tunneling length a is much smaller than both R and 〈d〉, the analytical equations show that smaller crystals exhibit a faster tunneling recombination rate. However, when the tunneling length a is of the same order of magnitude as both R and 〈d〉, the opposite effect is observed, with smaller crystals exhibiting a slower tunneling recombination rate. As the crystal size increases, the rate of tunneling in both cases reaches the limit expected for bulk materials. In the second case we examine the situation where the concentrations of electrons and positive ions are equal at all times. In this situation there is no analytical equation available to describe the process, and the crystal size effects are simulated by using Monte Carlo (MC) techniques. The two opposite behaviors as a function of the crystal size are also observed in these MC simulations. The effect of sample temperature is also studied by extending the MC simulations to include thermal characteristics of the defects. The relevance of the simulated results for luminescence dosimetry is discussed.

  18. Establishment of Low Energy Building materials and Equipment Database Based on Property Information

    NASA Astrophysics Data System (ADS)

    Kim, Yumin; Shin, Hyery; eon Lee, Seung

    2018-03-01

    The purpose of this study is to provide reliable service of materials information portal through the establishment of public big data by collecting and integrating scattered low energy building materials and equipment data. There were few cases of low energy building materials database in Korea have provided material properties as factors influencing material pricing. The framework of the database was defined referred with Korea On-line E-procurement system. More than 45,000 data were gathered by the specification of entities and with the gathered data, price prediction models for chillers were suggested. To improve the usability of the prediction model, detailed properties should be analysed for each item.

  19. Parametric estimation for reinforced concrete relief shelter for Aceh cases

    NASA Astrophysics Data System (ADS)

    Atthaillah; Saputra, Eri; Iqbal, Muhammad

    2018-05-01

    This paper was a work in progress (WIP) to discover a rapid parametric framework for post-disaster permanent shelter’s materials estimation. The intended shelters were reinforced concrete construction with bricks as its wall. Inevitably, in post-disaster cases, design variations were needed to help suited victims condition. It seemed impossible to satisfy a beneficiary with a satisfactory design utilizing the conventional method. This study offered a parametric framework to overcome slow construction-materials estimation issue against design variations. Further, this work integrated parametric tool, which was Grasshopper to establish algorithms that simultaneously model, visualize, calculate and write the calculated data to a spreadsheet in a real-time. Some customized Grasshopper components were created using GHPython scripting for a more optimized algorithm. The result from this study was a partial framework that successfully performed modeling, visualization, calculation and writing the calculated data simultaneously. It meant design alterations did not escalate time needed for modeling, visualization, and material estimation. Further, the future development of the parametric framework will be made open source.

  20. Building and Managing Electronic Resources in Digital Era in India with Special Reference to IUCAA and NIV, Pune: A Comparative Case Study

    NASA Astrophysics Data System (ADS)

    Sahu, H. K.; Singh, S. N.

    2015-04-01

    This paper discusses and presents a comparative case study of two libraries in Pune, India, Inter-University Centre for Astronomy and Astrophysics and Information Centre and Library of National Institute of Virology (Indian Council of Medical Research). It compares how both libraries have managed their e-resource collections, including acquisitions, subscriptions, and consortia arrangements, while also developing a collection of their own resources, including pre-prints and publications, video lectures, and other materials in an institutional repository. This study illustrates how difficult it is to manage electronic resources in a developing country like India, even though electronic resources are used more than print resources. Electronic resource management can be daunting, but with a systematic approach, various problems can be solved, and use of the materials will be enhanced.

  1. BIPV: a real-time building performance study for a roof-integrated facility

    NASA Astrophysics Data System (ADS)

    Aaditya, Gayathri; Mani, Monto

    2018-03-01

    Building integrated photovoltaic system (BIPV) is a photovoltaic (PV) integration that generates energy and serves as a building envelope. A building element (e.g. roof and wall) is based on its functional performance, which could include structure, durability, maintenance, weathering, thermal insulation, acoustics, and so on. The present paper discusses the suitability of PV as a building element in terms of thermal performance based on a case study of a 5.25 kWp roof-integrated BIPV system in tropical regions. Performance of PV has been compared with conventional construction materials and various scenarios have been simulated to understand the impact on occupant comfort levels. In the current case study, PV as a roofing material has been shown to cause significant thermal discomfort to the occupants. The study has been based on real-time data monitoring supported by computer-based building simulation model.

  2. Improving a Case-Control Study of Multiple Sclerosis Using Formative Research

    PubMed Central

    Williamson, Dhelia M.; Wagner, Laurie; Henry, Judy P.

    2015-01-01

    Formative research (i.e. focus groups and key informant interviews) was conducted to understand risk perceptions and identify barriers to participation in a case-control study of environmental exposures and genetic susceptibility as risk factors for multiple sclerosis (MS). Individuals with MS were recruited to participate in a focus group discussion and individual interviews. Participants were asked to review and comment on study materials and process including participation, interview, genetic testing, confidentiality, and questionnaire. A structured discussion guide was used with all participants to ensure uniformity and coverage of all predetermined topics. Participants reported an increased likelihood of participation if they were informed about the study by their neurologist and not a government agency. All participants expressed willingness to provide a blood sample for genotyping but disagreed about the setting for the blood draw (at home or in a lab). Participants were concerned that they would not receive their individual genotyping results. The study protocol and materials were revised based on comments from the focus group participants. Formative research is an under-utilized resource for researchers conducting epidemiologic studies. Even with limited resources, piloting study materials with individuals similar to the proposed study population can provide opportunities to make modifications to effectively meet the needs of participants and promote participation and retention. PMID:25741529

  3. A training tool for visual aids. Using tracing techniques to create visual aids.

    PubMed

    Clark, M; Walters, J E; Wileman, R

    1982-01-01

    This training tool explains the use of tracing techniques to create visuals requiring few materials and no training of special skills in drawing. Magazines, books, posters, and many other materials contain photographs and drawings which can be used to create visual aids for health training and public health education. The materials required are pencils, an eraser, crayons or colored marking pens, paper clips, tracing and drawing paper, carbon paper, and sources of visual images. The procedure is described. The material was prepared by INTRAH staff members. Other materials include how to evaluate teaching, how to create a family health case study and training in group dynamics.

  4. Mechanical properties of experimental composites with different calcium phosphates fillers.

    PubMed

    Okulus, Zuzanna; Voelkel, Adam

    2017-09-01

    Calcium phosphates (CaPs)-containing composites have already shown good properties from the point of view of dental restorative materials. The purpose of this study was to examine the crucial mechanical properties of twelve hydroxyapatite- or tricalcium phosphate-filled composites. The raw and surface-treated forms of both CaP fillers were applied. As a reference materials two experimental glass-containing composites and one commercial dental restorative composite were applied. Nano-hardness, elastic modulus, compressive, flexural and diametral tensile strength of all studied materials were determined. Application of statistical methods (one-way analysis of variance and cluster agglomerative analysis) allowed for assessing the similarities between examined materials according to the values of studied parameters. The obtained results show that in almost all cases the mechanical properties of experimental CaPs-composites are comparable or even better than mechanical properties of examined reference materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. ASER core curriculum illustration project: aortic intramural hematoma (IMH).

    PubMed

    Perez-Girbes, Alexandre; Dunham, Gregor M; Linnau, Ken F

    2017-04-01

    This is the 23rd installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at http://www.aseronline.org/curriculum/toc.htm .

  6. Seismic waves in heterogeneous material: subcell resolution of the discontinuous Galerkin method

    NASA Astrophysics Data System (ADS)

    Castro, Cristóbal E.; Käser, Martin; Brietzke, Gilbert B.

    2010-07-01

    We present an important extension of the arbitrary high-order discontinuous Galerkin (DG) finite-element method to model 2-D elastic wave propagation in highly heterogeneous material. In this new approach we include space-variable coefficients to describe smooth or discontinuous material variations inside each element using the same numerical approximation strategy as for the velocity-stress variables in the formulation of the elastic wave equation. The combination of the DG method with a time integration scheme based on the solution of arbitrary accuracy derivatives Riemann problems still provides an explicit, one-step scheme which achieves arbitrary high-order accuracy in space and time. Compared to previous formulations the new scheme contains two additional terms in the form of volume integrals. We show that the increasing computational cost per element can be overcompensated due to the improved material representation inside each element as coarser meshes can be used which reduces the total number of elements and therefore computational time to reach a desired error level. We confirm the accuracy of the proposed scheme performing convergence tests and several numerical experiments considering smooth and highly heterogeneous material. As the approximation of the velocity and stress variables in the wave equation and of the material properties in the model can be chosen independently, we investigate the influence of the polynomial material representation on the accuracy of the synthetic seismograms with respect to computational cost. Moreover, we study the behaviour of the new method on strong material discontinuities, in the case where the mesh is not aligned with such a material interface. In this case second-order linear material approximation seems to be the best choice, with higher-order intra-cell approximation leading to potential instable behaviour. For all test cases we validate our solution against the well-established standard fourth-order finite difference and spectral element method.

  7. [Evidential value of dental materials identification by infrared spectroscopy in forensic medicine opinionating].

    PubMed

    Wachowiak, Roman; Strach, Bogna

    2007-01-01

    The potential for a release of dental restoration material or a spontaneous loss of a tooth structure fragment in the course of mastication frequently requires a reliable identification of the lost fragment in order to confirm its origin. The consequences of incidental mechanical injuries -- in view of the presence of dangerous solid fragments -- become particularly important in cases of using a chewing gum. The problem involves distinguishing between the structure of a fragment of restoration or a broken tooth structure and incidental contaminants of chewing gum produced in the process of gum manufacturing. The consequences of mechanical injuries or exposure to potential structural tooth damage in the course of gum chewing provide a subject for numerous litigations against manufacturer of chewing gum and require appropriate identification of the material. The studies were conducted using solid phase infrared spectroscopy in the range of 500-4000 wavelength (cm(-1)) for a quick identification of dental materials used in the dental practice. A database of infrared transmission spectra characteristic of commonly employed dental filling materials was prepared to provide a systemic reference system, useful in controversial interpretation cases.

  8. Making good use of online case study materials.

    PubMed

    Keefer, Matthew Wilks

    2005-07-01

    Web-based access to engaging instructional materials for SEE instruction represents an increasingly viable and attractive opportunity for educators. This paper will review research findings that demonstrate important differences in more experienced and novice ethical responses to engaging online materials, including authentic cases, codes, and commentaries. Results demonstrate that experienced ethical thinkers are more likely than novices to appeal to middle level principles that identify professional role-specific obligations (RSO); to make greater use of professional knowledge in order to recognize moral issues and relevant facts; and to employ more 'contextually sensitive' reasoning strategies when crafting resolutions to moral problems--e.g., identify alternative moral issues, assess the moral implications of actions, and provide alternative practical resolutions to conflicts. These findings suggest that when effectively integrated into SEE courses, authentic instructional materials have the potential to effectively challenge students and enhance student learning. However, there is evidence that the uses and benefits of these materials are not well understood. In the second part of this paper, five research-based instructional principles will be identified and discussed that can help SEE instructors better understand how to effectively integrate these materials into their courses.

  9. The roles of thermal insulation and heat storage in the energy performance of the wall materials: a simulation study.

    PubMed

    Long, Linshuang; Ye, Hong

    2016-04-07

    A high-performance envelope is the prerequisite and foundation to a zero energy building. The thermal conductivity and volumetric heat capacity of a wall are two thermophysical properties that strongly influence the energy performance. Although many case studies have been performed, the results failed to give a big picture of the roles of these properties in the energy performance of an active building. In this work, a traversal study on the energy performance of a standard room with all potential wall materials was performed for the first time. It was revealed that both heat storage materials and insulation materials are suitable for external walls. However, the importances of those materials are distinct in different situations: the heat storage plays a primary role when the thermal conductivity of the material is relatively high, but the effect of the thermal insulation is dominant when the conductivity is relatively low. Regarding internal walls, they are less significant to the energy performance than the external ones, and they need exclusively the heat storage materials with a high thermal conductivity. These requirements for materials are consistent under various climate conditions. This study may provide a roadmap for the material scientists interested in developing high-performance wall materials.

  10. The roles of thermal insulation and heat storage in the energy performance of the wall materials: a simulation study

    PubMed Central

    Long, Linshuang; Ye, Hong

    2016-01-01

    A high-performance envelope is the prerequisite and foundation to a zero energy building. The thermal conductivity and volumetric heat capacity of a wall are two thermophysical properties that strongly influence the energy performance. Although many case studies have been performed, the results failed to give a big picture of the roles of these properties in the energy performance of an active building. In this work, a traversal study on the energy performance of a standard room with all potential wall materials was performed for the first time. It was revealed that both heat storage materials and insulation materials are suitable for external walls. However, the importances of those materials are distinct in different situations: the heat storage plays a primary role when the thermal conductivity of the material is relatively high, but the effect of the thermal insulation is dominant when the conductivity is relatively low. Regarding internal walls, they are less significant to the energy performance than the external ones, and they need exclusively the heat storage materials with a high thermal conductivity. These requirements for materials are consistent under various climate conditions. This study may provide a roadmap for the material scientists interested in developing high-performance wall materials. PMID:27052186

  11. Contingency Contracting in Support of Conus Disasters: A Case Study of the 1994 Northridge Earthquake, 2005 Hurricane Katrina and 2012 Hurricane Sandy

    DTIC Science & Technology

    2014-06-01

    Northridge earthquake response. The City of Los Angeles and the State of California required contracts to address recycling of demolition materials to the...materials directly recycled and material removed from the site on the enclosed recycling log found within this Contract. Documentation includes...related to recycling disaster debris:  “Incentive payment: The City will pay tipping fees using the existing authorization letter; however, only source

  12. The LARSYS educational package: Instructor's notes. [instructional materials for training people to analyze remotely sensed data

    NASA Technical Reports Server (NTRS)

    Lindenlaub, J. C.; Davis, S. M.

    1974-01-01

    Materials are presented for assisting instructors in teaching the LARSYS Educational Package, which is a set of instructional materials to train people to analyze remotely sensed multispectral data. The seven units of the package are described. These units are: quantitative remote sensing, overview of the LARSYS software system, the 2780 remote terminal, demonstration of LARSYS on the 2780 remote terminal, exercises, guide to multispectral data analysis, and a case study using LARSYS for analysis of LANDSAT data.

  13. A Comparative Study of Multi-material Data Structures for Computational Physics Applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garimella, Rao Veerabhadra; Robey, Robert W.

    The data structures used to represent the multi-material state of a computational physics application can have a drastic impact on the performance of the application. We look at efficient data structures for sparse applications where there may be many materials, but only one or few in most computational cells. We develop simple performance models for use in selecting possible data structures and programming patterns. We verify the analytic models of performance through a small test program of the representative cases.

  14. Numerical Simulation of the Motion of Aerosol Particles in Open Cell Foam Materials

    NASA Astrophysics Data System (ADS)

    Solovev, S. A.; Soloveva, O. V.; Popkova, O. S.

    2018-03-01

    The motion of aerosol particles in open cell foam material is studied. The porous medium is investigated for a three-dimensional case with detailed simulation of cellular structures within an ordered geometry. Numerical calculations of the motion of particles and their deposition due to inertial and gravitational mechanisms are performed. Deposition efficiency curves for a broad range of particle sizes are constructed. The effect deposition mechanisms have on the efficiency of the porous material as a filter is analyzed.

  15. Applying Corpus-Based Findings to Form-Focused Instruction: The Case of Reported Speech

    ERIC Educational Resources Information Center

    Barbieri, Federica; Eckhardt, Suzanne E. B.

    2007-01-01

    Arguing that the introduction of corpus linguistics in teaching materials and the language classroom should be informed by theories and principles of SLA, this paper presents a case study illustrating how corpus-based findings on reported speech can be integrated into a form-focused model of instruction. After overviewing previous work which…

  16. Totally Unofficial: Raphael Lemkin and the Genocide Convention. The Making History Series

    ERIC Educational Resources Information Center

    Eshet, Dan

    2007-01-01

    This case study highlighting the story of Raphael Lemkin challenges everyone to think deeply about what it will take for individuals, groups, and nations to take up Lemkin's challenge. To make this material accessible for classrooms, this resource includes several components: an introduction by Genocide scholar Omer Bartov; a historical case study…

  17. An Empirical Evaluation of a Broad Ranging E-Text Adoption with Recommendations for Improving Deployment Success for Students

    ERIC Educational Resources Information Center

    Chapman, Jared R.; Seeley, Eugene L.; Wright, Norman S.; Glenn, Lowell M.; Adams, Lynn L.

    2016-01-01

    Electronic course materials have several advantages over printed materials. While these advantages create an enticing argument for the adoption of electronic textbooks, there are disadvantages that may hobble e-text adoption. This case study investigates the e-text adoption process for 50 class sections across 8 business disciplines with 27…

  18. A Manual for the Illinois Student Longitudinal Case Study System (ISLCS). Procedures and Materials for Planning and Implementing the ISLCS.

    ERIC Educational Resources Information Center

    Carvell, Fred; Carvell, Joan B.

    Designed for local school and district vocational educators, this manual contains instructions and materials necessary to plan and implement a student longitudinal followup system. Part 1 provides background information and definitions used in the system. In part 2 are described the 11 major activities that must be undertaken by local program…

  19. Digital Course Materials: A Case Study of the Apple iPad in the Academic Environment

    ERIC Educational Resources Information Center

    Cameron, Andrea H.; Bush, Michael H.

    2011-01-01

    The newness of the iPad device creates a phenomenon unique and unstudied in the academic environment. By merging the innovations of electronic text, e-reader, and multi-modal functionality, the iPad tablet device can act as an e-reader providing digital course materials as well as a range of other supplementary academic applications. This…

  20. The Effects of the Design and Development of a Chemistry Curriculum Reform on Teachers' Professional Growth: A Case Study

    ERIC Educational Resources Information Center

    Coenders, Fer; Terlouw, Cees; Dijkstra, Sanne; Pieters, Jules

    2010-01-01

    A curriculum innovation requires new learning material for students and a preparation program for teachers, in which teacher learning is a key ingredient. In this paper we describe how three experienced teachers, involved in the development and subsequent classroom enactment of student learning material for context-based chemistry education,…

  1. Developing a Material-Dialogic Approach to Pedagogy to Guide Science Teacher Education

    ERIC Educational Resources Information Center

    Hetherington, Lindsay; Wegerif, Rupert

    2018-01-01

    Dialogic pedagogy is being promoted in science teacher education but the literature on dialogic pedagogy tends to focus on explicit voices, and so runs the risk of overlooking the important role that material objects often play in science education. In this paper we use the findings of a teacher survey and classroom case study to argue that there…

  2. Learning Peace (and Conflict): The Role of Primary Learning Materials in Peacebuilding in Post-War Afghanistan, South Sudan and Sri Lanka

    ERIC Educational Resources Information Center

    Vanner, Catherine; Akseer, Spogmai; Kovinthan, Thursica

    2017-01-01

    Post-war education is usually considered a positive contributor to peacebuilding; however, it can also reinforce divisive perspectives. Textbooks and learning materials can be instrumental in maintaining or exacerbating existing inequalities. This paper uses case study literature reviews of Afghanistan, South Sudan and Sri Lanka to explore the…

  3. Science Teacher Decision-Making in a Climate of Heightened Accountability: A Rhizomatic Case Study Analysis of Two Science Departments in New York City

    ERIC Educational Resources Information Center

    Purohit, Kiran Dilip

    2017-01-01

    Secondary science teachers make many daily decisions in the enactment of curriculum. Although curriculum materials are widely available to address science content, practices, and skills, the consideration that goes into deciding how and whether to use such materials is complicated by teachers' beliefs about science, their understandings of…

  4. Tribology and Friction of Soft Materials: Mississippi State Case Study

    DTIC Science & Technology

    2010-03-18

    elastomers , foams, and fabrics. B. Develop internal state variable (ISV) material model. Model will be calibrated using database and verified...Rubbers Natural rubber Santoprene (Vulcanized Elastomer ) Styrene Butadiene Rubber (SBR) Foams Polypropylene Foam Polyurethane Foam Fabrics Kevlar...Axially symmetric model PC Disk PC Numerical Implementation in FEM Codes Experiment SEM Optical methods ISV Model Void Nucleation FEM Analysis

  5. Should the U.S. Army Adopt New 5.56mm Ammunition Cartridge Designs to Reduce Overall Ammunition Weight?

    DTIC Science & Technology

    2011-06-10

    developing alternative materials or configurations for ammunition cases.4 By using suitable widely available lightweight materials in the case of these...and civilian weapons manufacturers’ materials are accurate. The 5.56mm cartridge will still be the primary caliber of ammunition used in U.S. Army...in this case). External ballistics refers to all events concerning a projectile after it leaves the launcher, or barrel , and before achieves

  6. Genetics, mental illness, and complex disease: development and distribution of an interactive CD-ROM for genetic counselors. Final report for period 15 August 2000 - 31 December 2002

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McInerney, Joseph D.

    2003-03-31

    "Genetics and Major Psychiatric Disorders: A Program for Genetic Counselors" provides an introduction to psychiatric genetics, with a focus on the genetics of common complex disease, for genetics professionals. The program is available as a CD-ROM and an online educational resource. The on-line version requires a direct internet connection. Each educational module begins with an interactive case study that raises significant issues addressed in each module. In addition, case studies provided throughout the educational materials support teaching of major concepts. Incorporated throughout the content are expert video clips, video clips from individuals affected by psychiatric illness, and optional "learn more"more » materials that offer greater depth about a particular topic. The structure of the CD-ROM permits self-navigation, but we have suggested a sequence that allows materials to build upon each other. At any point in the materials, users may pause and look up terms in the glossary or review the DSM-IV criteria for selected psychiatric disorders. A detailed site map is available for those who choose to self navigate through the content.« less

  7. Characteristic Features of Hanging: A Study in Rural District of Central India.

    PubMed

    Ambade, Vipul Namdeorao; Kolpe, Dayanand; Tumram, Nilesh; Meshram, Satin; Pawar, Mohan; Kukde, Hemant

    2015-09-01

    The ligature mark is the most relevant feature of hanging. This study was undertaken with a view to determine the characteristic features of hanging and its association with ligature material or mode of suspension. Of a total medicolegal deaths reported at an Apex Medical Centre, hanging was noted in 4.1% cases, all suicidal with mortality rate of 1.5 per 100,000 population per year. The hanging was complete in 67.7% with nylon rope as the commonest type of ligature material used for ligation. The hanging mark was usually single, situated above thyroid cartilage, incomplete, prominent, and directed toward nape of neck. The mark of dribbling of saliva was seen in 11.8% cases. Facial congestion, petechial hemorrhage, and cyanosis were significantly seen in partial hanging. Though occasionally reported, the argent line was noted in 78.7% hanging deaths with neck muscle hemorrhage in 23.6% cases. Fracture of neck structure was predominant in complete hanging. © 2015 American Academy of Forensic Sciences.

  8. Investigation on the effects of temperature dependency of material parameters on a thermoelastic loading problem

    NASA Astrophysics Data System (ADS)

    Kumar, Anil; Mukhopadhyay, Santwana

    2017-08-01

    The present work is concerned with the investigation of thermoelastic interactions inside a spherical shell with temperature-dependent material parameters. We employ the heat conduction model with a single delay term. The problem is studied by considering three different kinds of time-dependent temperature and stress distributions applied at the inner and outer surfaces of the shell. The problem is formulated by considering that the thermal properties vary as linear function of temperature that yield nonlinear governing equations. The problem is solved by applying Kirchhoff transformation along with integral transform technique. The numerical results of the field variables are shown in the different graphs to study the influence of temperature-dependent thermal parameters in various cases. It has been shown that the temperature-dependent effect is more prominent in case of stress distribution as compared to other fields and also the effect is significant in case of thermal shock applied at the two boundary surfaces of the spherical shell.

  9. Effects of fabrication methods on spin relaxation and crystallite quality in Tm-doped ? powders studied using spectral hole burning

    NASA Astrophysics Data System (ADS)

    Lutz, Thomas; Veissier, Lucile; Thiel, Charles W.; Woodburn, Philip J. T.; Cone, Rufus L.; Barclay, Paul E.; Tittel, Wolfgang

    2016-01-01

    High-quality rare-earth-ion (REI) doped materials are a prerequisite for many applications such as quantum memories, ultra-high-resolution optical spectrum analyzers and information processing. Compared to bulk materials, REI doped powders offer low-cost fabrication and a greater range of accessible material systems. Here we show that crystal properties, such as nuclear spin lifetime, are strongly affected by mechanical treatment, and that spectral hole burning can serve as a sensitive method to characterize the quality of REI doped powders. We focus on the specific case of thulium doped ? (Tm:YAG). Different methods for obtaining the powders are compared and the influence of annealing on the spectroscopic quality of powders is investigated on a few examples. We conclude that annealing can reverse some detrimental effects of powder fabrication and, in certain cases, the properties of the bulk material can be reached. Our results may be applicable to other impurities and other crystals, including color centers in nano-structured diamond.

  10. Environmental degradation of composites for marine structures: new materials and new applications

    PubMed Central

    2016-01-01

    This paper describes the influence of seawater ageing on composites used in a range of marine structures, from boats to tidal turbines. Accounting for environmental degradation is an essential element in the multi-scale modelling of composite materials but it requires reliable test data input. The traditional approach to account for ageing effects, based on testing samples after immersion for different periods, is evolving towards coupled studies involving strong interactions between water diffusion and mechanical loading. These can provide a more realistic estimation of long-term behaviour but still require some form of acceleration if useful data, for 20 year lifetimes or more, are to be obtained in a reasonable time. In order to validate extrapolations from short to long times, it is essential to understand the degradation mechanisms, so both physico-chemical and mechanical test data are required. Examples of results from some current studies on more environmentally friendly materials including bio-sourced composites will be described first. Then a case study for renewable marine energy applications will be discussed. In both cases, studies were performed first on coupons at the material level, then during structural testing and analysis of large components, in order to evaluate their long-term behaviour. This article is part of the themed issue ‘Multiscale modelling of the structural integrity of composite materials’. PMID:27242304

  11. Zirconium: The material of the future in modern implantology.

    PubMed

    Kubasiewicz-Ross, Paweł; Dominiak, Marzena; Gedrange, Tomasz; Botzenhart, Ute U

    2017-01-01

    The authors present the contemporary state of knowledge concerning alternative materials for dental implantology. First of all, factors influencing osseointegration are stated. The most important factors seem to be the type of implant surface. Among the numerous parameters describing them, the most important are: average roughness and porous density. Some studies proved that materials with comparable surface roughness provide similar osseointegration. In modern implantology titanium is the material still considered as a "gold standard". However, aesthetic features of titanium still bear several disadvantages, especially in the case of periodontium with a thin biotype in the anterior, aesthetic sensitive area of the jaw. If a titanium implant is used in such a case, the mucosa at the implant's neck may become grayish and, consequently limits the success of the overall treatment. That was the reason for seeking alternative materials to manufacture dental implants. Initiated by general medicine, mainly orthopedics, the search led to the discovery of zirconium dioxide used in dental implantology. A small number of complications, good chemical parameters, anticorrosion, mechanical strength, elasticity module close to the one of steel, and especially biocompatibility made zirconium a perfect material for this purpose, although this material presents several problems in achieving optimal roughness. In this overview one of the probable methods, a process of partial synterization, is presented.

  12. An experimental study on fatigue performance of cryogenic metallic materials for IMO type B tank

    NASA Astrophysics Data System (ADS)

    Lee, Jin-Sung; You, Won-Hyo; Yoo, Chang-Hyuk; Kim, Kyung-Su; Kim, Yooil

    2013-12-01

    Three materials SUS304, 9% Ni steel and Al 5083-O alloy, which are considered possible candidate for International Maritime Organization (IMO) type B Cargo Containment System, were studied. Monotonic tensile, fatigue, fatigue crack growth rate and Crack Tip Opening Displacement tests were carried out at room, intermediate low (-100 °C) and cryogenic (-163 °C) temperatures. The initial yield and tensile strengths of all materials tended to increase with decreasing temperature, whereas the change in elastic modulus was not as remarkable. The largest and smallest improvement ratio of the initial yield strengths due to a temperature reduction were observed in the SUS304 and Al 5083- O alloy, respectively. The fatigue strengths of the three materials increased with decreasing temperature. The largest increase in fatigue strength was observed in the Al 5083-O alloy, whereas the 9% Ni steel sample showed the smallest increase. In the fatigue crack growth rate test, SUS304 and Al 5083-O alloy showed a decrease in the crack propagation rate, due to decrease in temperature, but no visible improvement in da/dN was observed in the case of 9% Ni steel. In the Crack Tip Opening Displacement (CTOD) test, CTOD values were converted to critical crack length for the comparison with different thickness specimens. The critical crack length tended to decrease in the case of SUS304 and increase for the Al 5083-O alloy with decreasing temperature. In case of 9% Ni steel, change of critical crack length was not observed due to temperature decrease. In addition, the changing material properties according to the temperature of the LNG tank were analyzed according to the international code for the construction and equipment of ships carrying liquefied gases in bulk (IGC code) and the rules of classifications.

  13. The Development of Nanotechnologies and Advanced Materials Industry in Science and Entrepreneurship: Socioeconomic and Technical Indicators. A Case Study of Latvia (Part One)

    NASA Astrophysics Data System (ADS)

    Geipele, I.; Geipele, S.; Staube, T.; Ciemleja, G.; Zeltins, N.

    2016-08-01

    The present scientific paper is the first part of two publications, where the authors obtain results from the scientific research presented in a series of works on the development of the nanotechnologies and advanced materials industry in science and entrepreneurship in Latvia. The study has a focus on finding proper socioeconomic and technical indicators. It provides resume on a scope of the study. The paper contains the developed structure of engineering economic indicator system, determined groups of indicators for assessment of the development of nanotechnologies and advanced materials industry in Latvia and results of the evaluation of the obtained statistics on the economic indicators.

  14. Evolution of a Materials Data Infrastructure

    NASA Astrophysics Data System (ADS)

    Warren, James A.; Ward, Charles H.

    2018-06-01

    The field of materials science and engineering is writing a new chapter in its evolution, one of digitally empowered materials discovery, development, and deployment. The 2008 Integrated Computational Materials Engineering (ICME) study report helped usher in this paradigm shift, making a compelling case and strong recommendations for an infrastructure supporting ICME that would enable access to precompetitive materials data for both scientific and engineering applications. With the launch of the Materials Genome Initiative in 2011, which drew substantial inspiration from the ICME study, digital data was highlighted as a core component of a Materials Innovation Infrastructure, along with experimental and computational tools. Over the past 10 years, our understanding of what it takes to provide accessible materials data has matured and rapid progress has been made in establishing a Materials Data Infrastructure (MDI). We are learning that the MDI is essential to eliminating the seams between experiment and computation by providing a means for them to connect effortlessly. Additionally, the MDI is becoming an enabler, allowing materials engineering to tie into a much broader model-based engineering enterprise for product design.

  15. Case studies of soil in art

    NASA Astrophysics Data System (ADS)

    Feller, C.; Landa, E. R.; Toland, A.; Wessolek, G.

    2015-08-01

    The material and symbolic appropriations of soil in artworks are numerous and diverse, spanning many centuries and artistic traditions, from prehistoric painting and ceramics to early Renaissance works in Western literature, poetry, paintings, and sculpture, to recent developments in film, architecture, and contemporary art. Case studies focused on painting, installation, and film are presented with the view of encouraging further exploration of art about, in, and with soil as a contribution to raising soil awareness.

  16. Using Novels as Bases for Case Studies: Michael Crichton's State of Fear and Global Warming

    ERIC Educational Resources Information Center

    Herreid, Clyde Freeman

    2005-01-01

    Every time an English professor assigns a novel, poem, or play for a class to analyze, he or she is using the case study method. Why shouldn't scientists do the same? They don't always have to write their own material. After all, there are some pretty good writers out there, and some of them actually slip a lot of science into the nooks and…

  17. Additive Manufacturing (3D Printing) Aircraft Parts and Tooling at the Maintenance Group Level

    DTIC Science & Technology

    The purpose of this research was to evaluate the effectiveness of additive manufacturing (AM) or 3D printing for the Air Force aircraft maintenance...case study of the 552d MXGs 3D printing operation explores their use of a Fused Deposition Modeling (FDM) thermoplastic material to manufacture parts...by applying the case study’s analysis toward a proof of concept, producing a C-130J Aft Cargo Door Rub Strip for 3D printing . The study concluded by

  18. Catheter-directed Endovascular Application of Thrombin: Report of 3 Cases and Review of the Literature

    PubMed Central

    Maybody, Majid; Madoff, David C.; Thornton, Raymond H; Morales, Steven A; Moskowitz, Chaya S; Hsu, Meier; Brody, Lynn A; Brown, Karen T; Covey, Anne M

    2017-01-01

    Purpose To report 3 new cases of catheter-directed endovascular application of thrombin and explore trends by analysis of published case series. Materials and Methods Institutional Review Board approved this retrospective study. All cases of non-tumoral arterial embolization performed from January 2003 to January 2015 at our institution were retrospectively reviewed. Thrombin was used in 7 of 589 cases. In 3 cases intra arterial thrombin was injected via catheter to treat active hemorrhage. Four cases were excluded due to percutaneous injection into visceral pseudoaneurysms (n=3) and making ex vivo autologous clot to be injected via catheter (n=1). Fisher’s exact and the Wilcoxon rank sum tests were used to assess for association with acute nontarget thrombosis. Results Catheter-directed thrombin was used in 3/589 (0.5%) cases at our institution. All three cases were technically successful with no further bleeding (100%). Nontarget thrombosis of proximal branches occurred in 2 patients (67%) with no significant clinical consequences. Including our 3 cases, a total of 28 cases were reviewed. Of the variables examined - location (p=0.99), size (p=0.66) and etiology of vascular lesion (p=0.92), pseudoaneurysm neck anatomy (p=0.14), thrombin units (p=0.47), volume (p=0.76) or technique of use of small doses (p=0.99), use of other embolic material (p=0.67) and use of adjunct techniques (p=0.99) - none were found to be significantly associated with acute nontarget thrombosis. Technical success was 96% with no reports of reperfusion after treatment. Conclusions Catheter-directed endovascular thrombin can be an additional tool to treat pseudoaneurysms not amenable to conventional embolization. Further studies are required to optimize technique and outcomes. PMID:27936421

  19. Reconstructing Harry: a genealogical study of a colonial family 'inside' and 'outside' the Grahamstown Asylum, 1888-1918.

    PubMed

    Wilbraham, Lindy

    2014-04-01

    Recent scholarship has explored the dynamics between families and colonial lunatic asylums in the late nineteenth century, where families actively participated in the processes of custodial care, committal, treatment and release of their relatives. This paper works in this historical field, but with some methodological and theoretical differences. The Foucauldian study is anchored to a single case and family as an illness narrative that moves cross-referentially between bureaucratic state archival material, psychiatric case records, and intergenerational family-storytelling and family photographs. Following headaches and seizures, Harry Walter Wilbraham was medically boarded from his position as Postmaster in the Cape of Good Hope Colony of South Africa with a 'permanent disease of the brain', and was committed to the Grahamstown Asylum in 1910, where he died the following year, aged 40 years. In contrast to writings about colonial asylums that usually describe several patient cases and thematic patterns in archival material over time and place, this study's genealogical lens examines one white settler male patient's experiences within mental health care in South Africa between 1908 and 1911. The construction of Harry's 'case' interweaves archival sources and reminiscences inside and outside the asylum, and places it within psychiatric discourse of the time, and family dynamics in the years that followed. Thus, this case study maps the constitution of 'patient' and 'family' in colonial life, c.1888-1918, and considers the calamity, uncertainty, stigma and silences of mental illness.

  20. EXPERIMENTAL STUDIES ON YELLOW FEVER IN NORTHERN PERU.

    PubMed

    Noguchi, H; Kligler, I J

    1921-01-31

    Fourteen typical cases of yellow fever were studied in northern Peru during an epidemic occurring in 1920, nine in Payta in March and April, and five in Morropon and Piura in April and May. The method of investigation was similar to that previously employed, but as the laboratory facilities were very meager certain changes were required. Although in Payta the work was handicapped by the lack of electric light, the scarcity of water and animal food, the unsuitability of the guinea pigs for inoculation, and the changes in culture media due to age, the results obtained under these adverse conditions were by no means negative. While in no instance was there a typical infection produced in animals, either by direct inoculation of blood or with culture materials, yet certain guinea pigs in each series showed temporary febrile reactions or definite hemorrhagic lesions of the lungs indicative of a mild leptospira infection. Direct search for Leptospira icteroides in the blood of patients or in culture materials was not made because the dark-field microscope could not be used. Subsequently, at Piura, the laboratory facilities were vastly, improved, the use of the dark-field microscope was made possible by means of a storage battery, and a fresh stock of young healthy guinea pigs was received from New York, and fresh rabbit serum obtained in Piura. In the study of the materials obtained from five cases of yellow fever in Morropon all these added facilities were taken advantage of, with the result that the outcome was positive and convincing. Cultures from the five cases were examined after 11, 12, and 13 days, and in those from three cases living leptospiras were found. By inoculation into suitable guinea pigs of culture material from these five cases, irrespective of whether or not leptospiras were detected under the dark-field microscope, a typical Leptospira icteroides infection was produced from four of the five cases. In one of these no leptospira had been detected in the culture tubes. Thus one case only yielded negative results, in that no leptospiras were found under the dark-field microscope and the animal inoculation was negative. The leptospira was demonstrated in the blood or organ emulsions of the infected guinea pigs, and further transmission of each strain to other guinea pigs was obtained and pure cultures were secured. A few points of practical significance appeared in the course of the present investigation. One is the importance of using fresh rabbit serum for culture media. Old rabbit serum, whether in pure form or incorporated with agar, etc., which had been kept for several months in a tropical climate, proved to be unsatisfactory for obtaining a growth of Leptospira icteroides. A second point of interest is the variation in susceptibility of guinea pigs to infection with Leptospira icteroides. In two of four series of positive animal inoculations with the Morropon culture materials only one-half of the guinea pigs inoculated with given materials developed typical symptoms. The other half either suffered from a transient mild infection, as evidenced by a few hemorrhagic foci in the lungs, or escaped infection altogether. From these facts it is highly probable that the lung lesions and febrile reactions observed in certain guinea pigs inoculated with the Payta materials were due to a mild leptospira infection. In a comparative experiment the native guinea pigs procured in Payta were found to be more resistant to the leptospira infection than those recently brought from New York. In fact, only a small portion of the former succumbed to typical infection even when inoculated with a virulent strain of Leptospira icteroides obtained from the Morropon epidemic. In conclusion it may be stated that of fourteen cases of yellow fever studied in Peru, a typical leptospira infection, together with the demonstration of the organism in experimentally infected guinea pigs, was obtained in four, while in the majority of instances indications of a mild, non-fatal leptospira infection were observed. In a few cases only were the results entirely negative. The leptospira isolated from Morropon cases of yellow fever, which is morphologically and culturally identical with the Guayaquil and Merida strains of Leptospira icteroides, was also shown by immunity test to be indistinguishable from the Guayaquil organism.

  1. [Breast cancer: histological prognosis from biopsy material].

    PubMed

    Veith, F; Picco, C

    1977-01-01

    Two histological factors to be taken into consideration for prognosis in pretreatment schedules of breast cancer have been studied on a group of 352 cases treated by non-mutilating therapeutics at the Fondation Curie between 1960 and 1970. The tumour material the slides of which we have reexamined "blindly", i.e. ignoring the evolution of the case had been obtained mostly by drill-biopsy. Histological groups and types have been determined following an analytical classification for computer purpose. The degree of malignancy was calculated with the method of Scarff-Bloom-Richardson. The analyzed data have been memorized on computer and then confronted with the elements of the T.N.M. classification and the survival of the patients involved. It appeared that if drill-biopsie have been performed correctly the histological type may be defined in eighty percent of cases. And it is likewise possible to calculate the histological grade of malignancy for each mammary cancer. With such a material the value for prognosis by means of the Scarff-Bloom-Richardson method still remains if applied only to adenocarcinoma of the "common infiltrating type".

  2. Manufacturing methods of a composite cell case for a Ni-Cd battery

    NASA Technical Reports Server (NTRS)

    Bauer, J. L.

    1979-01-01

    Basic manufacturing method refinements for using graphite epoxy material for a nickel cadmium battery cell case were performed to demonstrate production feasibility. The various facets of production scale-up, i.e., process and tooling development, together with material and process control, were integrated into a comprehensive manufacturing process that assures production reproducibility and product uniformity. Test results substantiate that a battery cell case produced from graphite epoxy pre-impregnated material, utilizing the internal pressure bag fabrication method, is feasible.

  3. Quantagenetics® analysis of laser-induced breakdown spectroscopic data: Rapid and accurate authentication of materials

    NASA Astrophysics Data System (ADS)

    McManus, Catherine E.; Dowe, James; McMillan, Nancy J.

    2018-07-01

    Many industrial and commercial issues involve authentication of such matters as the manufacturer or geographic source of a material, and quality control of materials, determining whether specific treatments have been properly applied, or if a material is authentic or fraudulent. Often, multiple analytical techniques and tests are used, resulting in expensive and time-consuming testing procedures. Laser-Induced Breakdown Spectroscopy (LIBS) is a rapid laser ablation spectroscopic analytical method. Each LIBS spectrum contains information about the concentration of every element, some isotopic ratios, and the molecular structure of the material, making it a unique and comprehensive signature of the material. Quantagenetics® is a multivariate statistical method based on Bayesian statistics that uses the Euclidian distance between LIBS spectra of materials to classify materials (US Patents 9,063,085 and 8,699,022). The fundamental idea behind Quantagenetics® is that LIBS spectra contain sufficient information to determine the origin and history of materials. This study presents two case studies that illustrate the method. LIBS spectra from 510 Colombian emeralds from 18 mines were classified by mine. Overall, 99.4% of the spectra were correctly classified; the success rate for individual mines ranges from 98.2% to 100%. Some of the mines are separated by distances as little as 200 m, indicating that the method uses the slight but consistent differences in composition to identify the mine of origin accurately. The second study used bars of 17-4 stainless steel from three manufacturers. Each of the three bars was cut into 90 coupons; 30 of each bar received no further treatment, another 30 from each bar received one tempering and hardening treatment, and the final 30 coupons from each bar received a different heat treatment. Using LIBS spectra taken from the coupons, the Quantagenetics® method classified the 270 coupons both by manufacturer (composition) and heat treatment (structure) with an overall success rate of 95.3%. Individual success rates range from 92.4% to 97.6%. These case studies were successful despite having no preconceived knowledge of the materials; artificial intelligence allows the materials to classify themselves without human intervention or bias. Multivariate analysis of LIBS spectra using the Quantagenetics® method has promise to improve quality control and authentication of a wide variety of materials in industrial enterprises.

  4. The Scientific and Technological area of the Programs of Curricular Diversification. Critical analysis of the available materials and a case study in Segovia province

    NASA Astrophysics Data System (ADS)

    Leal Insua, Maria Pilar

    This thesis is focused on the Scientific area of the Programs of Curricular Diversification, one of the Government actions for the attention to diversity in compulsory Secondary Education, established in the General Education Law (LOGSE: Ley de Ordenacion General del Sistema Educativo) of 1990. It has been carried out in Spain. In the thesis two different lines of work can be distinguished: (A) The analysis of material elaborated specifically for the mentioned area. We intent to know what materials have been elaborated and to analyze them; to this purpose we study the material spread in Congresses or Conferences, and also the articles published in magazines or specifically designed to be used in the Scientific area of the Programs of Curricular Diversification until year 2003. The analysis is made after classifying the material according to the format in which it appears (books, CDs, "Didactic Units"). (B) Two case studies, of evaluative character, carried out in two Secondary Schools in the province of Segovia (Spain), one of them in the city and another one in a rural population. The case studies are centered in the Scientific Area of the Programs of Curricular Diversification that last for two years. In the first of these Centers eight students took part in the Program; in the second, a total of seven. Throughout the investigation we observed that students who took part in the Programs obtained good academic results. Programs are proved to be effective in generating processes of academic success in pupils who were previously in situation of school failure and at risk of social exclusion. The success of these programs is fundamentally due to the following reasons: the low number of students involved, the fact that they are focused on basic knowledge, the reduced number of subjects studied. Besides, to offer the students the chance of a closer relationship with a few teachers increases their motivation and involvement in the programs. Key words: Attention to Diversity, Didactics of Experimental Sciences, Programs of curricular diversification, Scientific Technological Area

  5. Material characterisation with methods of nonlinear optics

    NASA Astrophysics Data System (ADS)

    Prylepa, A.; Reitböck, C.; Cobet, M.; Jesacher, A.; Jin, X.; Adelung, R.; Schatzl-Linder, M.; Luckeneder, G.; Stellnberger, K.-H.; Steck, T.; Faderl, J.; Stehrer, T.; Stifter, D.

    2018-01-01

    In this review, we present nonlinear optical methods, based on the second and third order nonlinear polarization, especially in the context of material characterization tasks outside the area of life sciences—for which these techniques are mostly designed. An overview of application studies reported to date is given, together with a discussion on the advantages and limits of the individual methods. Furthermore, new ways of experimentally combining different optical concepts are introduced, and their potential for characterisation and inspection tasks is evaluated in the context of various case studies, including the investigation of semiconductor surfaces, metals and related corrosion products, as well as of organic materials.

  6. Risk assessment during transport of radioactive materials through the Suez Canal

    NASA Astrophysics Data System (ADS)

    Sabek, M. G.; El-Shinawy, R. M. K.; Gomaa, M.

    1997-03-01

    In this paper a study for risk assessment of the impact of transporting radioactive materials, during the period 1986-1992, through the Suez Canal of Egypt is given. The code RADTRAN-IV was used for this study. The results of the code, for a normal case, show that the transportation of low activity materials such as uranium (U 3O 8) represent the main items that contribute significantly to the collective dose within the Suez Canal area (Port-Said, Ismailia and Suez). The values of the annual collective dose due to transportation of all radionuclide materials was found to be at a maximum in Suez town and is equal to 5.04 × 10 -8 Man-Sv for the whole populations. If we only consider the workder at the harbour (estimated to be 50 persons), the value of the annual collective dose is about 3.33 × 10 -4 Man-Sv. These values are less than the exemption value of 1 Man-Sv recommended by the IAEA. For the accident case, the following pathways are considered by the code: ground-shine, direct inhalation, inhalation of resuspended material and cloud-shine. The total values of the estimated risks for each radionuclide material are presented in table form and, in addition, health effects (genetic effects, GE, and latent cancer fatality), LCF) are discussed. The calculated values of the radiological risks are very low for the three towns, showing that no radiation-induced early deaths are to be expected.

  7. Central sorting and recovery of MSW recyclable materials: A review of technological state-of-the-art, cases, practice and implications for materials recycling.

    PubMed

    Cimpan, Ciprian; Maul, Anja; Jansen, Michael; Pretz, Thomas; Wenzel, Henrik

    2015-06-01

    Today's waste regulation in the EU comprises stringent material recovery targets and calls for comprehensive programs in order to achieve them. A similar movement is seen in the US where more and more states and communities commit to high diversion rates from landfills. The present paper reviews scientific literature, case studies and results from pilot projects, on the topic of central sorting of recyclable materials commonly found in waste from households. The study contributes, inter alia, with background understanding on the development of materials recovery, both in a historical and geographical perspective. Physical processing and sorting technology has reached a high level of maturity, and many quality issues linked to cross-contamination by commingling have been successfully addressed to date. New sorting plants tend to benefit from economies of scale, and innovations in automation and process control, which are targeted at curtailing process inefficiencies shown by operational practice. Technology developed for the sorting of commingled recyclables from separate collection is also being successfully used to upgrade residual MSW processing plants. The strongest motivation for central sorting of residual MSW is found for areas where source separation and separate collection is difficult, such as urban agglomerations, and can in such areas contribute to increasing recycling rates, either complementary to- or as a substitute for source separation of certain materials, such as plastics and metals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Computer model for refinery operations with emphasis on jet fuel production. Volume 2: Data and technical bases

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    The FORTRAN computing program predicts the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case. The report has sufficient detail for the information of most readers.

  9. Sound attenuation and absorption by micro-perforated panels backed by anisotropic fibrous materials: Theoretical and experimental study

    NASA Astrophysics Data System (ADS)

    Bravo, Teresa; Maury, Cédric

    2018-07-01

    Enhancing the attenuation or the absorption of low-frequency noise using lightweight bulk-reacting liners is still a demanding task in surface and air transport systems. The aim of this study is to understand the physical mechanisms involved in the attenuation and absorption properties of partitions made up of a thin micro-perforated panel (MPP) rigidly backed by a cavity filled with anisotropic fibrous material. Such a layout is denoted as a MPPF partition. Analytical models are formulated in the flow and no-flow cases to predict the axial damping of the least attenuated wave in a MPPF partition as well as the plane wave absorption coefficient. They account for a rigid or an elastic MPP facing a bulk-reacting fully-anisotropic material. A cost-efficient solution of the propagation constant for the least attenuated mode is obtained using a simulated annealing search method as well as a low-frequency approximation to the axial attenuation. The normal incidence absorption model is assessed in the no-flow case against pressure-velocity measurements of the surface impedance over a MPPF partition filled with fibreglass material. A parametric study is conducted to evaluate the MPP and the cavity constitutive parameters that mostly enhance the axial attenuation and sound absorption properties, with special interest on the MPP airframe relative velocity. This sensitivity study provides guidelines that could be used to further reduce the search space in parametric or impedance optimization studies.

  10. Evaluating Opportunities to Improve Material and Energy Impacts in Commodity Supply Chains.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanes, Rebecca J.; Carpenter, Alberta

    When evaluated at the process level, next-generation technologies may be more energy and emissions intensive than current technology. However, many advanced technologies have the potential to reduce material and energy consumption in upstream or downstream processing stages. In order to fully understand the benefits and consequences of technology deployment, next-generation technologies should be evaluated in context, as part of a supply chain. This work presents the Material Flows through Industry (MFI) scenario modeling tool. The MFI tool is a cradle-to-gate linear network model of the U.S. industrial sector that can model a wide range of manufacturing scenarios, including changes inmore » production technology, increases in industrial energy efficiency, and substitution between functionally equivalent materials. The MFI tool was developed to perform supply chain scale analyses in order to quantify the impacts and benefits of next-generation technologies and materials at that scale. For the analysis presented in this paper, the MFI tool is utilized to explore a case study comparing a steel supply chain to the supply chains of several functionally equivalent materials. Several of the alternatives to the baseline steel supply chain include next-generation production technologies and materials. Results of the case study show that aluminum production scenarios can out-perform the steel supply chain by using either an advanced smelting technology or an increased aluminum recycling rate. The next-generation material supply chains do not perform as well as either aluminum or steel, but may offer additional use phase reductions in energy and emissions that are outside the scope of the MFI tool. Future work will combine results from the MFI tool with a use phase analysis.« less

  11. Glioma and occupational exposure in Sweden, a case-control study.

    PubMed Central

    Rodvall, Y; Ahlbom, A; Spännare, B; Nise, G

    1996-01-01

    OBJECTIVES: The aim of the study was to analyse whether any job titles, industrial codes, and certain occupational exposures were associated with an increased risk of glioma. METHODS: A population based case-control study of incident primary brain tumours in adults was carried out in Uppsala, Sweden in the period 1987-90. The study included 192 cases of glioma and 192 matched controls. It also included cases with other tumours of the central nervous system with matched controls. Information from all 343 controls was used in this study. Information was collected by means of a questionnaire that was sent to all subjects. An occupational hygienist reviewed the questionnaires for self reported exposures to substances and assessed whether these reported exposures were plausible or not in the corresponding occupation. RESULTS: The kappa coefficient for those classified by the two methods ranged between 0.46 and 0.88, and they were almost the same for cases and controls. For men exposed to solvents a relative risk (RR) of 2.6 (95% CI 1.3 to 5.2) was found. For men exposed to pesticides the RR was 1.8 (95% CI 0.6 to 5.1), and for plastic materials the RR was 3.6 (95% CI 1.0 to 12.4). For men employed in forestry and logging the RR was 2.2 (95% CI 0.9 to 5.3) and in basic metal industries 2.0 (95% CI 1.0 to 4.0). CONCLUSION: An increased risk of glioma was associated with use of solvents, pesticides, and plastic materials but this should be interpreted with some caution. PMID:8983463

  12. As(V) and P Competitive Sorption on Soils, By-Products and Waste Materials

    PubMed Central

    Rivas-Pérez, Ivana María; Paradelo-Núñez, Remigio; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-01-01

    Batch-type experiments were used to study competitive As(V) and P sorption on various soils and sorbent materials. The materials assayed were a forest soil, a vineyard soil, pyritic material, granitic material, coarsely and finely ground mussel shell, calcinated mussel shell ash, pine sawdust and slate processing fines. Competition between As(V) and P was pronounced in the case of both soils, granitic material, slate fines, both shells and pine sawdust, showing more affinity for P. Contrary, the pyritic material and mussel shell ash showed high and similar affinity for As(V) and P. These results could be useful to make a correct use of the soils and materials assayed when focusing on As and P removal in solid or liquid media, in circumstances where both pollutants may compete for sorption sites. PMID:26690456

  13. Digital case-based learning system in school.

    PubMed

    Gu, Peipei; Guo, Jiayang

    2017-01-01

    With the continuing growth of multi-media learning resources, it is important to offer methods helping learners to explore and acquire relevant learning information effectively. As services that organize multi-media learning materials together to support programming learning, the digital case-based learning system is needed. In order to create a case-oriented e-learning system, this paper concentrates on the digital case study of multi-media resources and learning processes with an integrated framework. An integration of multi-media resources, testing and learning strategies recommendation as the learning unit is proposed in the digital case-based learning framework. The learning mechanism of learning guidance, multi-media materials learning and testing feedback is supported in our project. An improved personalized genetic algorithm which incorporates preference information and usage degree into the crossover and mutation process is proposed to assemble the personalized test sheet for each learner. A learning strategies recommendation solution is proposed to recommend learning strategies for learners to help them to learn. The experiments are conducted to prove that the proposed approaches are capable of constructing personalized sheets and the effectiveness of the framework.

  14. A forensic identification case and DPid - can it be a useful tool?

    PubMed Central

    de QUEIROZ, Cristhiane Leão; BOSTOCK, Ellen Marie; SANTOS, Carlos Ferreira; GUIMARÃES, Marco Aurélio; da SILVA, Ricardo Henrique Alves

    2017-01-01

    Abstract Objective The aim of this study was to show DPid as an important tool of potential application to solve cases with dental prosthesis, such as the forensic case reported, in which a skull, denture and dental records were received for analysis. Material and Methods Human identification is still challenging in various circumstances and Dental Prosthetics Identification (DPid) stores the patient’s name and prosthesis information and provides access through an embedded code in dental prosthesis or an identification card. All of this information is digitally stored on servers accessible only by dentists, laboratory technicians and patients with their own level of secure access. DPid provides a complete single-source list of all dental prosthesis features (materials and components) under complete and secure documentation used for clinical follow-up and for human identification. Results and Conclusion If DPid tool was present in this forensic case, it could have been solved without requirement of DNA exam, which confirmed the dental comparison of antemortem and postmortem records, and concluded the case as a positive identification. PMID:28678955

  15. Digital case-based learning system in school

    PubMed Central

    Gu, Peipei

    2017-01-01

    With the continuing growth of multi-media learning resources, it is important to offer methods helping learners to explore and acquire relevant learning information effectively. As services that organize multi-media learning materials together to support programming learning, the digital case-based learning system is needed. In order to create a case-oriented e-learning system, this paper concentrates on the digital case study of multi-media resources and learning processes with an integrated framework. An integration of multi-media resources, testing and learning strategies recommendation as the learning unit is proposed in the digital case-based learning framework. The learning mechanism of learning guidance, multi-media materials learning and testing feedback is supported in our project. An improved personalized genetic algorithm which incorporates preference information and usage degree into the crossover and mutation process is proposed to assemble the personalized test sheet for each learner. A learning strategies recommendation solution is proposed to recommend learning strategies for learners to help them to learn. The experiments are conducted to prove that the proposed approaches are capable of constructing personalized sheets and the effectiveness of the framework. PMID:29107965

  16. Low Temperature Regenerator Study.

    DTIC Science & Technology

    1979-08-01

    ultrafine particles in the regenerator matrix, he must increase the gross refrigeration to overcome the poorer efficiency of conventional materials. The...well as being, in many cases, highly toxic. 4.2 Production of Particles There are a surprisingly large number of ways that ultrafine particles can be...however, those materials provide some evidence that the surface enhance- ment effect survives when ultrafine particles are embedded, and even alloyed

  17. The Role of Postgraduate Students in Co-Authoring Open Educational Resources to Promote Social Inclusion: A Case Study at the University of Cape Town

    ERIC Educational Resources Information Center

    Hodgkinson-Williams, Cheryl; Paskevicius, Michael

    2012-01-01

    Like many universities worldwide, the University of Cape Town (UCT) in South Africa has joined the open educational resources (OER) movement, making a selection of teaching and learning materials available through its OER directory, UCT OpenContent. However, persuading and then supporting busy academics to share their teaching materials as OER…

  18. [Policy recommendations based on SWOT analysis for agricultural industrialization of traditional Chinese medicinal materials--a case study of uncariae ramulus cum uncis from Jianhe county in Guizhou province].

    PubMed

    Hu, Yong; Huo, Ke-Yi; Xiang, Hua

    2013-09-01

    This thesis reviews the historical background of agricultural industrialization, and analyzes the major theories of agricultural industrialization. It also utilizes SWOT analysis method to discuss the industrialization of traditional Chinese medicinal materials in Jianhe county, and finally it puts forward the recommendations for its further development.

  19. Students' Acceptance of File Sharing Systems as a Tool for Sharing Course Materials: The Case of Google Drive

    ERIC Educational Resources Information Center

    Sadik, Alaa

    2017-01-01

    Students' perceptions about both ease of use and usefulness are fundamental factors in determining their acceptance and successful use of technology in higher education. File sharing systems are one of these technologies and can be used to manage and deliver course materials and coordinate virtual teams. The aim of this study is to explore how…

  20. Newly invented biobased materials from low-carbon, diverted waste fibers: research methods, testing, and full-scale application in a case study structure

    Treesearch

    Julee A Herdt; John Hunt; Kellen Schauermann

    2016-01-01

    This project demonstrates newly invented, biobased construction materials developed by applying lowcarbon, biomass waste sources through the Authors’ engineered fiber processes and technology. If manufactured and applied large-scale the project inventions can divert large volumes of cellulose waste into high-performance, low embodied energy, environmental construction...

  1. The Effects of Different Levels of Disfluency on Learning Outcomes and Cognitive Load

    ERIC Educational Resources Information Center

    Seufert, Tina; Wagner, Felix; Westphal, Julia

    2017-01-01

    In some cases difficult-to-read learning materials lead to better performance than easy to-read materials. This phenomenon is called the disfluency effect and is attributed to a subjective feeling of task difficulty resulting in a deeper learning approach. In two studies (n[subscript 1] = 67, n[subscript 2] = 73) we investigated the impact of…

  2. Material Matters for Learning in Virtual Networks: A Case Study of a Professional Learning Programme Hosted in a Google+ Online Community

    ERIC Educational Resources Information Center

    Ackland, Aileen; Swinney, Ann

    2015-01-01

    In this paper, we draw on Actor-Network Theories (ANT) to explore how material components functioned to create gateways and barriers to a virtual learning network in the context of a professional development module in higher education. Students were practitioners engaged in family learning in different professional roles and contexts. The data…

  3. Fly pupae and puparia as potential contaminants of forensic entomology samples from sites of body discovery.

    PubMed

    Archer, M S; Elgar, M A; Briggs, C A; Ranson, D L

    2006-11-01

    Fly pupae and puparia may contaminate forensic entomology samples at death scenes if they have originated not from human remains but from animal carcasses or other decomposing organic material. These contaminants may erroneously lengthen post-mortem interval estimates if no pupae or puparia are genuinely associated with the body. Three forensic entomology case studies are presented, in which contamination either occurred or was suspected. In the first case, blow fly puparia collected near the body were detected as contaminants because the species was inactive both when the body was found and when the deceased was last sighted reliably. The second case illustrates that contamination may be suspected at particularly squalid death scenes because of the likely presence of carcasses or organic material. The third case involves the presence at the body discovery site of numerous potentially contaminating animal carcasses. Soil samples were taken along transects to show that pupae and puparia were clustered around their probable sources.

  4. Light microscopic study of periapical lesions associated with asymptomatic apical periodontitis.

    PubMed

    Kabak, S L; Kabak, Y S; Anischenko, S L

    2005-04-01

    The purpose of the study has been to evaluate the degree of chronic inflammation in tissues surrounding the apex of the tooth root in patients with apical periodontitis in the remission phase. The material included 37 apical granulomas and radicular cysts obtained as a result of apiectomy, and 20 teeth which were removed together with the focus of the periapical inflammation. Routine histological techniques, as well as the immunofluorescent and immuno-chemical methods were used to examine the material. Despite the absence of clinical symptoms in 23 of 57 cases, the morphological signs of chronic inflammation were observed in the apical area of the tooth root. Morphological signs of viral invasion of epithelial and stromal cells in the radicular cyst wall were revealed in six cases. The presence of the virus of Herpes simplex I in epithelial cells (five cases) and adenoviral invasion (one case) was confirmed by immuno-fluorescent and immuno-chemical methods. Histological examination often reveals morphological signs of an active inflammatory process in the periapical tissues of patients treated during clinical remission. In our opinion, the presence of viruses in the epithelial cells of the radicular cyst may contribute to the persistence of the active stage of the inflammatory process.

  5. Comparison of wear between occlusal splint materials and resin composite materials.

    PubMed

    Reyes-Sevilla, M; Kuijs, R H; Werner, A; Kleverlaan, C J; Lobbezoo, F

    2018-07-01

    Tooth wear in bruxing patients often results in a need for treatment with composite restorations. In some cases, bruxing patients receive an occlusal splint as a protective means as well. However, the wear between these opposing materials has not been investigated yet. The aim of this in vitro study was to assess the wear of different splint materials against resin composite materials. A two-body wear test was conducted using the ACTA wear machine. The materials selected for this study were three composites used for direct restorations (Filtek Z250, CLEARFIL AP-X, and Filtek Supreme XT) and four occlusal splints materials, viz. a polyamide resin (ThermoSens) an conventional (hand-processed), milled and printed polymethylmethacrylate (PMMA). As antagonistic materials, stainless steel, Filtek Supreme XT and CLEARFIL AP-X were used. The wear rate of the seven materials was determined after 200 000 cycles, using a profilometry. The rates were analysed using two-way ANOVA and post hoc Tukey's tests. The wear rates were significantly higher for the conventional and milled PMMA materials than for all other materials (P < .001). The wear rates of printed PMMA and the polyamide resin were comparable to composite wear rates. The antagonist materials have minor or no influence on the amount of wear of the various splint materials (P < .001). In conclusion, different splint materials yielded different wear rates for all antagonist materials tested. Keeping in mind that this study is an experimental in vitro study, this finding enables practitioners to choose the splint material necessary according to their patients' needs. © 2018 John Wiley & Sons Ltd.

  6. Gram-negative bacteremia: which empirical antibiotic therapy?

    PubMed

    Shoai Tehrani, M; Hajage, D; Fihman, V; Tankovic, J; Cau, S; Day, N; Visseaux, C; Carbonnelle, E; Kouatchet, A; Cattoir, V; Nhan, T X; Corvec, S; Jacquier, H; Jauréguy, F; Le Monnier, A; Morand, P; Zahar, J R

    2014-04-01

    Given the increasing frequency of cefotaxime-resistant strains, third-generation cephalosporins (3GC e.g. cefotaxime, ceftriaxone) might not be recommended any longer as empirical antibiotic therapy for community-acquired Gram-negative bacteremia (CA-GNB). We conducted a multicenter prospective descriptive study including patients with CA-GNB. Two hundred and nineteen patients were included. Escherichia coli and Pseudomonas aeruginosa were the most frequently isolated species in 63% (n=138) and 11% (n=24) of the cases, respectively. The prevalence of cefotaxime-resistance reached 18% (n=39) mostly due to intrinsic resistance (27 cases, 12%). The presence of invasive material (P<0.001), the origin of the patient (Paris region or West of France) (P=0.006), and home health care (P<0.001) were variables predicting resistant GNB. The negative predictive value for resistance in patients with invasive material coming from the West of France, or without invasive material and with home health care was 94%. The positive predictive value for patients with invasive material living in Paris, or without invasive material and with home health care only reached 58 and 54%, respectively. Using 3GC for CA-GNB due to cefotaxime-resistant strains was relatively frequent, ESBL-producing Enterobacteriaceae being rarely involved. Our study highlights the role of local epidemiology; before any changes to first-line antibiotic therapy, local epidemiological data should be taken into account. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. Materials library collections as tools for interdisciplinary research

    PubMed Central

    2018-01-01

    ABSTRACT This paper examines how materials libraries are used as tools for interdisciplinary collaboration in 3 research projects that inhabit a disciplinary triangle between materials research, design and user needs: PhysFeel, which explores how materials collections can be used in psychological therapies; Light.Touch.Matters, a design-led project to develop new smart materials; and Hands of X, which uses materials collections to develop a bespoke prosthetics service. The paper analyses and contrasts these case studies to better understand the affordances and limitations of materials collections when used as research, translational and design tools. We conclude that in collaborations between materials researchers, designers and end users, tensions arise as a result of the primacy that each partner gives to creativity, the development of new knowledge and to solving societal problems. The use of a materials library addresses many of these issues but is not a panacea for all the problems associated with interdisciplinary working. PMID:29576803

  8. Computational predictions of energy materials using density functional theory

    NASA Astrophysics Data System (ADS)

    Jain, Anubhav; Shin, Yongwoo; Persson, Kristin A.

    2016-01-01

    In the search for new functional materials, quantum mechanics is an exciting starting point. The fundamental laws that govern the behaviour of electrons have the possibility, at the other end of the scale, to predict the performance of a material for a targeted application. In some cases, this is achievable using density functional theory (DFT). In this Review, we highlight DFT studies predicting energy-related materials that were subsequently confirmed experimentally. The attributes and limitations of DFT for the computational design of materials for lithium-ion batteries, hydrogen production and storage materials, superconductors, photovoltaics and thermoelectric materials are discussed. In the future, we expect that the accuracy of DFT-based methods will continue to improve and that growth in computing power will enable millions of materials to be virtually screened for specific applications. Thus, these examples represent a first glimpse of what may become a routine and integral step in materials discovery.

  9. Materials library collections as tools for interdisciplinary research.

    PubMed

    Wilkes, S E; Miodownik, M A

    2018-01-01

    This paper examines how materials libraries are used as tools for interdisciplinary collaboration in 3 research projects that inhabit a disciplinary triangle between materials research, design and user needs: PhysFeel , which explores how materials collections can be used in psychological therapies; Light.Touch.Matters , a design-led project to develop new smart materials; and Hands of X , which uses materials collections to develop a bespoke prosthetics service. The paper analyses and contrasts these case studies to better understand the affordances and limitations of materials collections when used as research, translational and design tools. We conclude that in collaborations between materials researchers, designers and end users, tensions arise as a result of the primacy that each partner gives to creativity, the development of new knowledge and to solving societal problems. The use of a materials library addresses many of these issues but is not a panacea for all the problems associated with interdisciplinary working.

  10. An evaluation of the discriminating power of an Integrated Ballistics Identification System® Heritage™system with the NIST standard cartridge case (Standard Reference Material 2461).

    PubMed

    Morris, Keith B; Law, Eric F; Jefferys, Roger L; Dearth, Elizabeth C; Fabyanic, Emily B

    2017-11-01

    Through analysis and comparison of firing pin, breech face, and ejector impressions, where appropriate, firearm examiners may connect a cartridge case to a suspect firearm with a certain likelihood in a criminal investigation. When a firearm is not present, an examiner may use the Integrated Ballistics Identification System (IBIS ® ), an automated search and retrieval system coupled with the National Integrated Ballistics Information Network (NIBIN), a database of images showing the markings on fired cartridge cases and bullets from crime scenes along with test fired firearms. For the purpose of measurement quality control of these IBIS ® systems the National Institute of Standards and Technology (NIST) initiated the Standard Reference Material (SRM) 2460/2461 standard bullets and cartridge cases project. The aim of this study was to evaluate the overall performance of the IBIS ® system by using NIST standard cartridge cases. By evaluating the resulting correlation scores, error rates, and percent recovery, both the variability between and within examiners when using IBIS ® , in addition to any inter- and intra-variability between SRM cartridge cases was observed. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Sterilization and disinfection in the physician's office.

    PubMed Central

    Drummond, D C; Skidmore, A G

    1991-01-01

    OBJECTIVE: To review the principles and practice of sterilization and disinfection of medical instruments in the office setting. DATA SOURCES: Searches of MEDLINE for articles published from 1980 to 1990 on disinfection, sterilization, cross infection, surgical instruments and iatrogenic disease, bibliographies, standard texts and reference material located in a central processing department. STUDY SELECTION: We reviewed surveys of decontamination practices in physicians' offices, reviews of current recommendations for office decontamination procedures, case reports of cross infection in offices and much of the standard reference material on decontamination theory and practice. DATA SYNTHESIS: There have been few surveys of physicians' decontamination practices and few case reports of cross infection. Office practitioners have little access to practical information on sterilization and disinfection. CONCLUSION: The increasing threat of cross infection from medical instruments calls for greater knowledge about decontamination. We have adapted material from various sources and offer a primer on the subject. PMID:1913427

  12. Structuring On-the-Job Training.

    ERIC Educational Resources Information Center

    DeJong, J. A.; Versloot, A. M.

    A study examined on-the-job training (OJT) at 8 Dutch firms employing more than 500 individuals each. A case study approach was used to investigate the following: job characteristics, program history, training schedules, training process, training materials, interaction with production, trainee characteristics, trainer characteristics, social…

  13. Travel Abroad as Culture Study.

    ERIC Educational Resources Information Center

    Jantz, Richard K.; Weaver, V. Phillips

    1992-01-01

    Encourages traveling by teachers to enrich the multicultural curriculum in their classes. Includes suggestions and resources for planning overseas trips and using them to broaden teachers' perspectives and to provide background material for curriculum development. Outlines "case studies" of trips to Hungary and Greece. (CFR)

  14. Harmonization - Two Years' of Transportation Regulation Lessons Learned

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Colborn, K.

    2007-07-01

    The U.S. Department of Transportation issued modifications to the Hazardous Materials Regulations in October, 2004 as part of an ongoing effort to 'harmonize' U.S. regulations with those of the International Atomic Energy Agency. The harmonization effort had several predictable effects on low level radioactive materials shipment that were anticipated even prior to their implementation. However, after two years' experience with the new regulations, transporters have identified several effects on transportation which were not entirely apparent when the regulations were first implemented. This paper presents several case studies in the transportation of low level radioactive materials since the harmonization rules tookmore » effect. In each case, an analysis of the challenge posed by the regulatory revision is provided. In some cases, more than one strategy for compliance was considered, and the advantages and disadvantages of each are discussed. In several cases, regulatory interpretations were sought and obtained, and these are presented to clarify the legitimacy of the compliance approach. The presentation of interpretations will be accompanied by reports of clarifying discussions with the U.S. DOT about the interpretation and scope of the regulatory change. Specific transportation issues raised by the revised hazardous materials regulations are reviewed, including: The new definition of radioactive material in accordance with isotope-specific concentration and total activity limits. The new hazardous materials regulations (HMR) created a new definition for radioactive material. A case study is presented for soils contaminated with low levels of Th-230. These soils had been being shipped for years as exempt material under the old 2,000 pCi/g concentration limit. Under the new HMR, these same soils were radioactive material. Further, in rail-car quantities their activity exceeded an A2 value, so shipment of the material in gondolas appeared to require an IP-2 package. Interpretations, discussions, and an exemption were obtained to secure the continued shipment of this material. A provision to allow 'natural' radioactive materials to be exempt from the requirements of the HMR at up to 10x the listed isotopic concentrations. The revised HMR exempts certain natural materials and ores from regulation as radioactive material at concentrations up to 10x that allowed if the materials are not natural. The term 'natural' is not well defined, and initial attempts to qualify for this exemption were thwarted by concerns over what degree of material processing, if any, materials could experience and still be considered 'natural'. The presentation includes an example from a project involving post-processed tungsten ore, and includes interpretations from the US DOT as well as clarifying language from current and drafted IAEA regulation and guidance. New packaging descriptions allowing the use of cargo containers as IP-2 and IP-3 packages in some applications. The revised HMR provides an alternate certification procedure under which standard cargo containers can be used as IP-2 and IP-3 containers. There has been some confusion about how this high level of certification can apply to standard cargo containers when other sections of the regulations make this certification available only to considerably more stout containers after rigorous testing. The discussion includes interpretive guidance from the US DOT, and from the UK Department of Transport clarifying the same provision in IAEA regulations. A new definition of contamination with apparently broad impact on the shipment of empty containers and conveyances. The revised HMR presented a definition of contamination not referenced by any other part of the HMR. The preamble to the revised HMR provides confusing guidance on the application of the definition to shipment of empty containers, and subsequent interpretive guidance letters appear to conflict with the preamble as well as with each other. The definition also has the effect of regulating materials for transport as radioactive even when US NRC and US Department of Energy (DOE) guidance documents suggest that the materials are free-releasable. This presentation provides the latest available information on this emerging issue. The presentation strives to provide the benefit of recent real-world experience in new aspects of the HMR. The examples provides should have broad application to shippers of a variety of low level radioactive materials in the US and internationally. (authors)« less

  15. Fine needle aspiration cytology in lymphadenopathy of HIV-positive cases.

    PubMed

    Saikia, U N; Dey, P; Jindal, B; Saikia, B

    2001-01-01

    To evaluate the role of fine needle aspiration biopsy (FNAB) material in 25 HIV-positive cases with lymphadenopathy. We selected 25 cases for the present study who were enzyme-linked immunosorbent assay positive for HIV (HIV-1). FNAB was performed as a routine, outdoor procedure with informed consent of the patient. For each case, along with routine May-Grünwald-Giemsa and hematoxylin and eosin staining, Ziehl-Neelsen staining for acid-fast bacilli and periodic acid-Schiff staining for fungi were performed wherever necessary. A total of 28 sites were aspirated from 25 HIV patients. All these patients were heterosexual, and none had a history of drug abuse. FNAB was performed under ultrasound guidance in all four cases of a retroperitoneal group of lymph nodes. The most common FNAB diagnosis was reactive lymphoid hyperplasia (10), followed by tuberculosis (8). There were three cases diagnosed as fungal infection (two, Cryptococcus; one, histoplasmosis). FNAB of a case of lymph node was suggestive of tuberculosis. There was one case each diagnosed as non-Hodgkin's lymphoma and squamous cell carcinoma (metastatic). One case of a small axillary lymph node did not yield representative material. FNAB is a relatively inexpensive initial investigative technique in the diagnosis and management of HIV-positive patients. It can obviate the need for surgical excision and enable immediate treatment of specific infections.

  16. A hybrid Dantzig-Wolfe, Benders decomposition and column generation procedure for multiple diet production planning under uncertainties

    NASA Astrophysics Data System (ADS)

    Udomsungworagul, A.; Charnsethikul, P.

    2018-03-01

    This article introduces methodology to solve large scale two-phase linear programming with a case of multiple time period animal diet problems under both nutrients in raw materials and finished product demand uncertainties. Assumption of allowing to manufacture multiple product formulas in the same time period and assumption of allowing to hold raw materials and finished products inventory have been added. Dantzig-Wolfe decompositions, Benders decomposition and Column generations technique has been combined and applied to solve the problem. The proposed procedure was programmed using VBA and Solver tool in Microsoft Excel. A case study was used and tested in term of efficiency and effectiveness trade-offs.

  17. Advanced Materials and Coatings for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2004-01-01

    In the application area of aerospace tribology, researchers and developers must guarantee the highest degree of reliability for materials, components, and systems. Even a small tribological failure can lead to catastrophic results. The absence of the required knowledge of tribology, as Professor H.P. Jost has said, can act as a severe brake in aerospace vehicle systems-and indeed has already done so. Materials and coatings must be able to withstand the aerospace environments that they encounter, such as vacuum terrestrial, ascent, and descent environments; be resistant to the degrading effects of air, water vapor, sand, foreign substances, and radiation during a lengthy service; be able to withstand the loads, stresses, and temperatures encountered form acceleration and vibration during operation; and be able to support reliable tribological operations in harsh environments throughout the mission of the vehicle. This presentation id divided into two sections: surface properties and technology practice related to aerospace tribology. The first section is concerned with the fundamental properties of the surfaces of solid-film lubricants and related materials and coatings, including carbon nanotubes. The second is devoted to applications. Case studies are used to review some aspects of real problems related to aerospace systems to help engineers and scientists to understand the tribological issues and failures. The nature of each problem is analyzed, and the tribological properties are examined. All the fundamental studies and case studies were conducted at the NASA Glenn Research Center.

  18. Finite Element Study on Continuous Rotating versus Reciprocating Nickel-Titanium Instruments.

    PubMed

    El-Anwar, Mohamed I; Yousief, Salah A; Kataia, Engy M; El-Wahab, Tarek M Abd

    2016-01-01

    In the present study, GTX and ProTaper as continuous rotating endodontic files were numerically compared with WaveOne reciprocating file using finite element analysis, aiming at having a low cost, accurate/trustworthy comparison as well as finding out the effect of instrument design and manufacturing material on its lifespan. Two 3D finite element models were especially prepared for this comparison. Commercial engineering CAD/CAM package was used to model full detailed flute geometries of the instruments. Multi-linear materials were defined in analysis by using real strain-stress data of NiTi and M-Wire. Non-linear static analysis was performed to simulate the instrument inside root canal at a 45° angle in the apical portion and subjected to 0.3 N.cm torsion. The three simulations in this study showed that M-Wire is slightly more resistant to failure than conventional NiTi. On the other hand, both materials are fairly similar in case of severe locking conditions. For the same instrument geometry, M-Wire instruments may have longer lifespan than the conventional NiTi ones. In case of severe locking conditions both materials will fail similarly. Larger cross sectional area (function of instrument taper) resisted better to failure than the smaller ones, while the cross sectional shape and its cutting angles could affect instrument cutting efficiency.

  19. Hunting for valuables from landfills and assessing their market opportunities A case study with Kudjape landfill in Estonia.

    PubMed

    Bhatnagar, Amit; Kaczala, Fabio; Burlakovs, Juris; Kriipsalu, Mait; Hogland, Marika; Hogland, William

    2017-06-01

    Landfill mining is an alternative technology that merges the ideas of material recycling and sustainable waste management. This paper reports a case study to estimate the value of landfilled materials and their respective market opportunities, based on a full-scale landfill mining project in Estonia. During the project, a dump site (Kudjape, Estonia) was excavated with the main objectives of extracting soil-like final cover material with the function of methane degradation. In total, about 57,777 m 3 of waste was processed, particularly the uppermost 10-year layer of waste. Manual sorting was performed in four test pits to determine the detailed composition of wastes. 11,610 kg of waste was screened on site, resulting in fine (<40 mm) and coarse (>40 mm) fractions with the share of 54% and 46%, respectively. Some portion of the fine fraction was sieved further to obtain a very fine grained fraction of <10 mm and analyzed for its potential for metals recovery. The average chemical composition of the <10 mm soil-like fraction suggests that it offers opportunities for metal (Cr, Cu, Ni, Pb, and Zn) extraction and recovery. The findings from this study highlight the importance of implementing best available site-specific technologies for on-site separation up to 10 mm grain size, and the importance of developing and implementing innovative extraction methods for materials recovery from soil-like fractions.

  20. Shuttle Case Study Collection Website Development

    NASA Technical Reports Server (NTRS)

    Ransom, Khadijah S.; Johnson, Grace K.

    2012-01-01

    As a continuation from summer 2012, the Shuttle Case Study Collection has been developed using lessons learned documented by NASA engineers, analysts, and contractors. Decades of information related to processing and launching the Space Shuttle is gathered into a single database to provide educators with an alternative means to teach real-world engineering processes. The goal is to provide additional engineering materials that enhance critical thinking, decision making, and problem solving skills. During this second phase of the project, the Shuttle Case Study Collection website was developed. Extensive HTML coding to link downloadable documents, videos, and images was required, as was training to learn NASA's Content Management System (CMS) for website design. As the final stage of the collection development, the website is designed to allow for distribution of information to the public as well as for case study report submissions from other educators online.

  1. Thermal contact resistance measurement of conduction cooled binary current lead joint block in cryocooler based self field I-V characterization facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kundu, Ananya, E-mail: ananya@ipr.res.in; Das, Subrat Kumar; Agarwal, Anees Bano Pooja

    2016-05-23

    In the present study thermal resistance of conduction cooled current lead joint block employing two different interfacial material namely AlN sheet and Kapton Film have been studied in the temperature range 5K-35K. In each case, the performance of different interlayer materials e.g. Indium foil for moderately pressurized contacts (contact pressure <1 MPa), and Apiezon N Grease, GE varnish for low pressurized contact (contact pressure <1 MPa) is studied. The performances of AlN joint with Indium foil and with Apeizon N Grease are studied and it is observed that the contact resistance reduces more with indium foil as compared to greasedmore » contact. The contact resistance measurements of Kapton film with Apiezon N grease and with GE varnish were also carried out in the same temperature range. A comparative study of AlN joint with Indium foil and Kapton with GE varnish as filler material is carried out to demonstrate better candidate material among Kapton and AlN for a particular filler material in the same temperature range.« less

  2. Curriculum Development in Literacy. Monograph No. 1. Part A: Proceedings and Methods of the First Regional Literacy Workshop (Udaipur, India, November 29-December 20, 1979). Part B: Curriculum Development in Literacy. Literacy Curriculum and Materials Development. Portfolio of Literacy Materials. Series I: Four Monographs.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and the Pacific.

    This monograph, one of four in a series, contains material on a particular aspect of literacy training. Developed from reports, papers, and case studies from the Regional Literacy Workshop (November 29-December 20, 1979) held in Udaipur, India, the monographs are suggested for use in training programs for literacy personnel as background…

  3. Cost/benefit analysis of advanced materials technologies for future aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Stephens, G. E.

    1980-01-01

    The materials technologies studied included thermal barrier coatings for turbine airfoils, turbine disks, cases, turbine vanes and engine and nacelle composite materials. The cost/benefit of each technology was determined in terms of Relative Value defined as change in return on investment times probability of success divided by development cost. A recommended final ranking of technologies was based primarily on consideration of Relative Values with secondary consideration given to changes in other economic parameters. Technologies showing the most promising cost/benefits were thermal barrier coated temperature nacelle/engine system composites.

  4. Mejoramiento de la Produccion de Materiales de Educacion en Poblacion para la Ensenanza Primaria y la Post-Alfabetizacion. Taller Regional (Santiago, Chile, 27 mayo-5 junio, 1987). Informe Final (Upgrading the Production of Population Education Materials for Primary Education and Post-Literacy. Regional Workshop (Santiago, Chile, May 27-June 5, 1987). Final Report.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.

    This report contains the results of an operational training workshop covering 11 case studies on the production of teaching materials for population education and used for elementary education, literacy, and post-literacy programs. The workshop covered the planning and design for the production of teaching materials including an eight step…

  5. A New Paradigm of Fatigue Variability Behavior and Implications for Life Prediction (Preprint)

    DTIC Science & Technology

    2006-06-01

    turbine engine materials is discussed. These were: the α+β titanium alloy, Ti-6Al-2Sn-4Zr-6Mo (Ti- 6 -2- 4 - 6 ) and a powder metallurgy (P/M) processed...MATERIALS AND EXPERIMENTAL PROCEDURE The materials in this study were an α+β titanium alloy, Ti- 6 -2- 4 - 6 and a P/M processed nickel-based superalloy. Two...and correlations between microstructure and loading variables vs. the mean behavior have been established in many cases [ 6 -9]. In α+β titanium alloys

  6. Course of Near-hanging Victims Succumbed to Death: A Seven Year Study

    PubMed Central

    Mugadlimath, Anand B.; Zine, K.U.; Farooqui, Jamebaseer M.; Phalke, Balaji J.

    2015-01-01

    Introduction: Near hanging refers to victims who survive a hanging injury following attempted hanging, long enough to reach hospital. Delayed deaths in near hanging patients are mostly due to complication of hanging. The purpose of this study was to evaluate the demographics, mortality patterns and cause of delayed deaths in near hanging victims. Materials and Methods: In this study autopsy files over a seven year period from 2007 to 2013 were reviewed, and data of near hanging deaths (attempted hanging cases who succumbed to death and subjected for medicolegal autopsy) was extracted. Records of 14,000 autopsies was reviewed, and 10 deceased having died delayed deaths after near hanging episode were identified. In each case, the patients’ details, including gender, age, type of suspension, type of ligature material used for hanging and subsequent hanging mark produced were reviewed using autopsy reports and photographs taken during autopsy. Results: Demographic and pathological aspects of the each case discussed to throw light on autopsy findings in victims who died following near hanging. Complete suspension was present in 3 cases, while partial suspension was present in 7 cases. Survivals in delayed death after near hanging episode have ranged from 9 h to 72 d. Hypoxic encephalopathy was the most common cause of death, followed by pneumonia. Conclusion: Most of the near hanging patients did succumb to hypoxic encephalopathy; however, consolidation of lungs (pneumonia) was the next common cause of death reflecting need for aggressive oxygen therapy and selective resuscitation should be performed in all such cases. PMID:25954634

  7. College-Based Case Studies in Using PowerPoint Effectively

    ERIC Educational Resources Information Center

    Inoue-Smith, Yukiko

    2016-01-01

    This study reexamined PowerPoint's potential to enhance traditional pedagogical practices in higher education. The study addressed (1) the conditions under which PowerPoint meets students' needs in typical lecture-based classrooms, (2) whether professors consider PowerPoint-based lectures more effective than lectures supported by material on…

  8. Low losses left-handed materials with optimized electric and magnetic resonance

    NASA Astrophysics Data System (ADS)

    Zhou, Xin; Liu, Yahong; Zhao, Xiaopeng

    2010-03-01

    We propose that the losses in left-handed materials (LHMs) can be significantly affected by changing the coupling relationship between electric and magnetic resonance. A double bowknot shaped structure (DBS) is used to construct the LHMs. And the magnetic resonance of the DBS, which resonated in the case of lower and higher frequencies than the electric resonant dip, is studied in simulation and experiment by tailoring the structural parameters. The case of magnetic resonance located at low electric resonance frequencies band is confirmed to have relatively low losses. Using full wave simulation of prism shaped structure composed of DBS unit cells, we prove the negative refraction behavior in such a frame. This study can serve as a guide for designing other similar metal-dielectric-metal (MDM) in low losses at terahertz or higher frequencies.

  9. Improving impact resistance of ceramic materials by energy absorbing surface layers

    NASA Technical Reports Server (NTRS)

    Kirchner, H. P.; Seretsky, J.

    1974-01-01

    Energy absorbing surface layers were used to improve the impact resistance of silicon nitride and silicon carbide ceramics. Low elastic modulus materials were used. In some cases, the low elastic modulus was achieved using materials that form localized microcracks as a result of thermal expansion anisotropy, thermal expansion differences between phases, or phase transformations. In other cases, semi-vitreous or vitreous materials were used. Substantial improvements in impact resistance were observed at room and elevated temperatures.

  10. A three-dimensional inverse finite element analysis of the heel pad.

    PubMed

    Chokhandre, Snehal; Halloran, Jason P; van den Bogert, Antonie J; Erdemir, Ahmet

    2012-03-01

    Quantification of plantar tissue behavior of the heel pad is essential in developing computational models for predictive analysis of preventive treatment options such as footwear for patients with diabetes. Simulation based studies in the past have generally adopted heel pad properties from the literature, in return using heel-specific geometry with material properties of a different heel. In exceptional cases, patient-specific material characterization was performed with simplified two-dimensional models, without further evaluation of a heel-specific response under different loading conditions. The aim of this study was to conduct an inverse finite element analysis of the heel in order to calculate heel-specific material properties in situ. Multidimensional experimental data available from a previous cadaver study by Erdemir et al. ("An Elaborate Data Set Characterizing the Mechanical Response of the Foot," ASME J. Biomech. Eng., 131(9), pp. 094502) was used for model development, optimization, and evaluation of material properties. A specimen-specific three-dimensional finite element representation was developed. Heel pad material properties were determined using inverse finite element analysis by fitting the model behavior to the experimental data. Compression dominant loading, applied using a spherical indenter, was used for optimization of the material properties. The optimized material properties were evaluated through simulations representative of a combined loading scenario (compression and anterior-posterior shear) with a spherical indenter and also of a compression dominant loading applied using an elevated platform. Optimized heel pad material coefficients were 0.001084 MPa (μ), 9.780 (α) (with an effective Poisson's ratio (ν) of 0.475), for a first-order nearly incompressible Ogden material model. The model predicted structural response of the heel pad was in good agreement for both the optimization (<1.05% maximum tool force, 0.9% maximum tool displacement) and validation cases (6.5% maximum tool force, 15% maximum tool displacement). The inverse analysis successfully predicted the material properties for the given specimen-specific heel pad using the experimental data for the specimen. The modeling framework and results can be used for accurate predictions of the three-dimensional interaction of the heel pad with its surroundings.

  11. Manufacturing methods of a composite cell case for a Ni-Cd battery

    NASA Technical Reports Server (NTRS)

    Bauer, J. L.; Bogner, R. S.; Lowe, E. P.; Orlowski, E.

    1979-01-01

    Graphite epoxy material for a nickel cadmium battery cell case has been evaluated and determined to perform in the simulated environment of the battery. The basic manufacturing method requires refinement to demonstrate production feasibility. The various facets of production scale-up, i.e., process and tooling development together with material and process control, have been integrated into a comprehensive manufacturing process that assures production reproducibility and product uniformity. Test results substantiate that a battery cell case produced from graphite epoxy pre-impregnated material utilizing internal pressure bag fabrication method is feasible.

  12. The potential of materials analysis by electron rutherford backscattering as illustrated by a case study of mouse bones and related compounds.

    PubMed

    Vos, Maarten; Tökési, Károly; Benkö, Ilona

    2013-06-01

    Electron Rutherford backscattering (ERBS) is a new technique that could be developed into a tool for materials analysis. Here we try to establish a methodology for the use of ERBS for materials analysis of more complex samples using bone minerals as a test case. For this purpose, we also studied several reference samples containing Ca: calcium carbonate (CaCO(3)) and hydroxyapatite and mouse bone powder. A very good understanding of the spectra of CaCO(3) and hydroxyapatite was obtained. Quantitative interpretation of the bone spectrum is more challenging. A good fit of these spectra is only obtained with the same peak widths as used for the hydroxyapatite sample, if one allows for the presence of impurity atoms with a mass close to that of Na and Mg. Our conclusion is that a meaningful interpretation of spectra of more complex samples in terms of composition is indeed possible, but only if widths of the peaks contributing to the spectra are known. Knowledge of the peak widths can either be developed by the study of reference samples (as was done here) or potentially be derived from theory.

  13. Sensitivity of the Boundary Plasma to the Plasma-Material Interface

    DOE PAGES

    Canik, John M.; Tang, X. -Z.

    2017-01-01

    While the sensitivity of the scrape-off layer and divertor plasma to the highly uncertain cross-field transport assumptions is widely recognized, the plasma is also sensitive to the details of the plasma-material interface (PMI) models used as part of comprehensive predictive simulations. Here in this paper, these PMI sensitivities are studied by varying the relevant sub-models within the SOLPS plasma transport code. Two aspects are explored: the sheath model used as a boundary condition in SOLPS, and fast particle reflection rates for ions impinging on a material surface. Both of these have been the study of recent high-fidelity simulation efforts aimedmore » at improving the understanding and prediction of these phenomena. It is found that in both cases quantitative changes to the plasma solution result from modification of the PMI model, with a larger impact in the case of the reflection coefficient variation. Finally, this indicates the necessity to better quantify the uncertainties within the PMI models themselves, and perform thorough sensitivity analysis to propagate these throughout the boundary model; this is especially important for validation against experiment, where the error in the simulation is a critical and less-studied piece of the code-experiment comparison.« less

  14. The effect of various deformation processes on the corrosion behavior of casing and tubing carbon steels in sweet environment

    NASA Astrophysics Data System (ADS)

    Elramady, Alyaa Gamal

    The aim of this research project is to correlate the plastic deformation and mechanical instability of casing steel materials with corrosion behavior and surface change, in order to identify a tolerable degree of deformation for casing steel materials. While the corrosion of pipeline and casing steels has been investigated extensively, corrosion of these steels in sweet environments with respect to plastic deformation due to bending, rolling, autofrettage, or handling needs more investigation. Downhole tubular expansion of pipes (casings) is becoming standard practice in the petroleum industry to repair damaged casings, shutdown perforations, and ultimately achieve mono-diameter wells. Tubular expansion is a cold-drawing metal forming process, which consists of running conical mandrels through casings either mechanically using a piston or hydraulically by applying a back pressure. This mechanism subjects the pipes to large radial plastic deformations of up to 30 pct. of the inner diameter. It is known that cold-working is a way of strengthening materials such as low carbon steel, but given that this material will be subjected to corrosive environments, susceptibility to stress corrosion cracking (SCC) should be investigated. This research studies the effect of cold-work, in the form of cold-rolling and cold-expansion, on the surface behavior of API 5CT steels when it is exposed to a CO2-containing environment. Cold-work has a pronounced influence on the corrosion behavior of both API 5CT K55 and P110 grade steels. The lowest strength grade steel, API 5CT K55, performed poorly in a corrosive environment in the slow strain rate test. The ductile material exhibited the highest loss in strength and highest susceptibility to stress corrosion cracking in a CO 2-containing environment. The loss in strength declined with cold-rolling, which can be ascribed to the surface compressive stresses induced by cold-work. On the other hand, API 5CT P110 grade steels showed higher susceptibility to SCC when they were cold-rolled and cold-expanded. The research found that surface compressive stresses have an effect on the SCC behavior of casing and tubing steels. The CO2 corrosion behavior and atomic processes at the corroding interface were investigated at laboratory temperature using electrochemical techniques. Cold-work was found to have an influence on the corrosion behavior of both API 5CT K55 and P110 grade steels. These behaviors were found to be material and process dependent. Surface evaluation techniques such as field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD) analysis did not detect formation of a protective scale. X-ray diffraction and X-ray photoelectron spectroscopy (XPS) analysis both detected the appearance of a scale that was traced back to magnetite.

  15. Accuracy of cytology in sub typing non small cell lung carcinomas.

    PubMed

    Patel, Trupti S; Shah, Majal G; Gandhi, Jahnavi S; Patel, Pratik

    2017-07-01

    Sub typing of non small cell lung carcinoma (NSCLC) has an important task in the era of molecular and targeted therapies. Differentiating between squamous cell carcinoma (SQCC) and adenocarcinoma (ADC) is challenging when limited material is available in lung carcinoma. We investigated the accuracy and feasibility of sub typing NSCLCs in cytology and small biopsy material. Concurrent cytology and biopsy material obtained in a single CT- guided procedure in lung carcinoma over a year period retrospectively. Both materials were individually sub typed and analyzed. Immunohistochemistry (IHC) was performed. Accuracy was determined by comparing the results with IHC. Total 107 of 126 cases of NSCLCs were included for analysis, where both cytology and biopsy material were adequate for interpretation. FNAC allowed tumor typing in 83 (77.6%) cases; 36 (33.6%) were ADC, 47 (43.9%) cases were SQCC and 24 (22.4%) cases diagnosed as Non-small cell carcinoma not otherwise specified (NSCLC-NOS). In biopsy, 86 cases (80.4%) were typed, among which 34 (31.8%) were ADC, 52 (48.6%) were SQCC and 21 (19.6%) were of NSCLC-NOS type. The result of Chi-square index was significant. With the aid of IHC, NSCLC-NOS reduced from 14 (13%) cases to 2 (1.9%) cases. Cytology and small biopsy specimens achieved comparable specificity and accuracy in sub-typing NSCLC and optimal results were obtain when findings from both modalities combine. The advantage of paired specimens is to maximize overall diagnostic yield and the remaining material will be available for ancillary technique like IHC or for molecular testing. Diagn. Cytopathol. 2017;45:598-603. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Performable Case Studies in Ethics Education.

    PubMed

    Robeson, Richard; King, Nancy M P

    2017-09-12

    Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry-the creation and performance of short case studies designed specifically to raise bioethics issues for discussion-represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio.

  17. Performable Case Studies in Ethics Education

    PubMed Central

    Robeson, Richard; King, Nancy M. P.

    2017-01-01

    Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry—the creation and performance of short case studies designed specifically to raise bioethics issues for discussion—represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio. PMID:28895903

  18. DFT Studies of Semiconductor and Scintillator Detection Materials

    NASA Astrophysics Data System (ADS)

    Biswas, Koushik

    2013-03-01

    Efficient radiation detection technology is dependent upon the development of new semiconductor and scintillator materials with advanced capabilities. First-principles based approaches can provide vital information about the structural, electrical, optical and defect properties that will help develop new materials. In addition to the predictive power of modern density functional methods, these techniques can be used to establish trends in properties that may lead to identifying new materials with optimum properties. We will discuss the properties of materials that are of current interest both in the field of scintillators and room temperature semiconductor detectors. In case of semiconductors, binary compounds such as TlBr, InI, CdTe and recently developed ternary chalcohalide Tl6SeI4 will be discussed. Tl6SeI4 mixes a halide (TlI) with a chalcogenide (Tl2Se), which results in an intermediate band gap (1.86 eV) between that of TlI (2.75 eV) and Tl2Se (0.6 eV). For scintillators, we will discuss the case of the elpasolite compounds whose rich chemical compositions should enable the fine-tuning of the band gap and band edges to achieve high light yield and fast scintillation response.

  19. Electron microscopy and microanalysis of the fiber-matrix interface in monolithic silicone carbide-based ceramic composite material for use in a fusion reactor application.

    PubMed

    Toplisek, Tea; Drazic, Goran; Novak, Sasa; Kobe, Spomenka

    2008-01-01

    A composite material made from continuous monolithic silicone carbide (SiC) fibers and a SiC-based matrix (SiC(f)/SiC), was prepared using a novel technique, i.e. adapted dip coating and infiltration of SiC fibers with a water suspension containing SiC particles and a sintering additive. This kind of material could be used in the first-wall blanket of a future fusion reactor. Using magnetron sputtering, the SiC fibers were coated with various thin layers (TiC, CrN, CrC, WC, DLC-diamond-like carbon) of the interface material by physical vapor deposition (PVD). Using scanning and transmission electron microscopy and microanalysis, detailed microstructural studies of the fiber-matrix interface were performed. Both samples, with coated and uncoated fibers, were examined under a load. The microcracks introduced by the Vickers indenter continued their path through the fibers, and thus caused the failure of the composite material, in the case of the uncoated fibers or deviated from their primary direction at the fiber-matrix interface in the case of the coated fibers.

  20. Mechanically Stretchable and Electrically Insulating Thermal Elastomer Composite by Liquid Alloy Droplet Embedment.

    PubMed

    Jeong, Seung Hee; Chen, Si; Huo, Jinxing; Gamstedt, Erik Kristofer; Liu, Johan; Zhang, Shi-Li; Zhang, Zhi-Bin; Hjort, Klas; Wu, Zhigang

    2015-12-16

    Stretchable electronics and soft robotics have shown unsurpassed features, inheriting remarkable functions from stretchable and soft materials. Electrically conductive and mechanically stretchable materials based on composites have been widely studied for stretchable electronics as electrical conductors using various combinations of materials. However, thermally tunable and stretchable materials, which have high potential in soft and stretchable thermal devices as interface or packaging materials, have not been sufficiently studied. Here, a mechanically stretchable and electrically insulating thermal elastomer composite is demonstrated, which can be easily processed for device fabrication. A liquid alloy is embedded as liquid droplet fillers in an elastomer matrix to achieve softness and stretchability. This new elastomer composite is expected useful to enhance thermal response or efficiency of soft and stretchable thermal devices or systems. The thermal elastomer composites demonstrate advantages such as thermal interface and packaging layers with thermal shrink films in transient and steady-state cases and a stretchable temperature sensor.

  1. Effects of Ultrasonics-Assisted Face Milling on Surface Integrity and Fatigue Life of Ni-Alloy 718

    NASA Astrophysics Data System (ADS)

    Suárez, Alfredo; Veiga, Fernando; de Lacalle, Luis N. López; Polvorosa, Roberto; Lutze, Steffen; Wretland, Anders

    2016-11-01

    This work investigates the effects of ultrasonic vibration-assisted milling on important aspects such us material surface integrity, tool wear, cutting forces and fatigue resistance. As an alternative to natural application of ultrasonic milling in brittle materials, in this study, ultrasonics have been applied to a difficult-to-cut material, Alloy 718, very common in high-temperature applications. Results show alterations in the sub-superficial part of the material which could influence fatigue resistance of the material, as it has been observed in a fatigue test campaign of specimens obtained with the application of ultrasonic milling in comparison with another batch obtained applying conventional milling. Tool wear pattern was found to be very similar for both milling technologies, concluding the study with the analysis of cutting forces, exhibiting certain improvement in case of the application of ultrasonic milling with a more stable evolution.

  2. Effects of combustibles on internal quasi-static loads

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sandoval, N.R.; Hokanson, J.C.; Esparza, E.D.

    1984-08-01

    The phenomenon of quasi-static pressure enhancement produced when combustible materials are placed near HE sources has been recently discovered. The effects of placing solid and liquid combustible materials near detonating explosives on internal blast loading was measured during tests conducted in a one-eighth scale model of a containment structure. In many cases, dramatic increases in gas pressures resulted. Principal conclusions of this study are: combustible materials near explosives can markedly increase gas pressures in enclosed structures; there is a lack of data on HE-combustible combinations; quasi-static loading calculations should include estimates of contributions from the burning of combustible materials whenevermore » such materials are expected to be in intimate contact with HE sources; and effects of combustibles should be investigated further to determine methods for prediction. Variations in charge to combustible mass, charge type, structure volume, degree of venting and degree of contact between HE and combustible sbould be studied.« less

  3. New Polymer Materials for the Laser Sintering Process: Polypropylene and Others

    NASA Astrophysics Data System (ADS)

    Wegner, Andreas

    Laser sintering of polymers gets more and more importance for small series production. However, there is only a little number of materials available for the process. In most cases parts are build up using polyamide 12 or polyamide 11. Reasons for that are high prices, a restricted availability, poor mechanical part properties or an insufficient understanding of the processing of other materials. These problems result from the complex processing conditions in laser sintering with high requirements on the material's characteristics. Within this area, at the chair for manufacturing technology fundamental knowledge was established. Aim of the presented study was to qualify different polymers for the laser sintering process. Polyethylene, polypropylene, polyamide 6, polyoxymethylene as well as polybutylene terephthalate were analyzed. Within the study problems of qualifying new materials are discussed using some examples. Furthermore, the processing conditions as well as mechanical properties of a new polypropylene compound are shown considering also different laser sintering machines.

  4. Love-type waves in functionally graded piezoelectric material (FGPM) sandwiched between initially stressed layer and elastic substrate

    NASA Astrophysics Data System (ADS)

    Saroj, Pradeep K.; Sahu, S. A.; Chaudhary, S.; Chattopadhyay, A.

    2015-10-01

    This paper investigates the propagation behavior of Love-type surface waves in three-layered composite structure with initial stress. The composite structure has been taken in such a way that a functionally graded piezoelectric material (FGPM) layer is bonded between initially stressed piezoelectric upper layer and an elastic substrate. Using the method of separation of variables, frequency equation for the considered wave has been established in the form of determinant for electrical open and short cases on free surface. The bisection method iteration technique has been used to find the roots of the dispersion relations which give the modes for electrical open and short cases. The effects of gradient variation of material constant and initial stress on the phase velocity of surface waves are discussed. Dependence of thickness on each parameter of the study has been shown explicitly. Study has been also done to show the existence of cut-off frequency. Graphical representation has been done to exhibit the findings. The obtained results are significant for the investigation and characterization of Love-type waves in FGPM-layered media.

  5. The case study of biomaterials and biominerals

    NASA Astrophysics Data System (ADS)

    Del Hoyo Martínez, Carmen

    2013-04-01

    The teaching of biomaterials as case study by on-line platform , susceptible to develop both individually and in groups, got different objectives proposed by the European Higher Education System, among which include: participate actively in the teaching-learning process by students, interpreting situations, adapt processes and solutions. It also improves oral and written communication, analytical skills and synthesis and also the ability to think critically. Biomaterials have their origin in biominerals. These are solid inorganic compounds of defined structure, consisting of molecular control mechanisms that operate in biological systems. Its main functions are: structural support, a reservoir of essential elements, sensors, mechanical protection and storage of toxic elements. Following the demand of materials compatible with certain functional systems of our body, developed biomaterials. Always meet the condition of biocompatibility. Should be tolerated by the body and do not provoke rejection. This involves a comprehensive study of physiological conditions and the anatomy of the body where a biomaterial has to be implemented. The possibility of generating new materials from biominerals has a major impact in medicine and other fields could reach as geology, construction, crystallography, etc. While the study of these issues is in its infancy today, can be viewed as an impact on the art and future technology. Planning case study that students would prepare its report for discussion in subgroups. Occurs then the pooling of individual analysis, joint case discussion and adoption by the subgroup of a consensual solution to the problem. The teacher as facilitator and coordinator of the final case analysis, sharing leads to group-wide class and said the unanimous decision reached by the students and gives his opinion on the resolution of the case. REFERENCES D.P. Ausubel. Psicología Educativa. Un punto de vista cognoscitivo. Trillas. Ed. 1983. E.W. Eisner. Procesos cognitivos y currículum. Una base para decidir lo que hay que enseñar. Martínez Roca Ed. 1987. C.O. Oriakhi. Polymer Nanocomposition Approach to Advanced Materials, Journal of Chemical Education. Vol. 77. 2000. 9-16. G. Lagaly & T. J. Pinnavaia.Clay Mineral-Polymer Nanocomposites, Applied Clay Science. Vol. 5. 1999. G. Gibbs. Changing lecturer's conceptions of teaching and learning through action research,. SRHE Press, 1995.

  6. Oral lymphoepithelial cyst: A clinicopathological study of 26 cases and review of the literature

    PubMed Central

    Sykara, Maria; Ntovas, Panagiotis; Tosios, Konstantinos I.; Sklavounou, Alexandra

    2017-01-01

    Introduction Τo describe the clinicopathological features of 26 oral lymphoepithelial cysts (LECs) and review the literature. Material and Methods Twenty-six cases of oral LECs diagnosed during a 37-year period were retrospectively collected. The patients’ gender and age, as well as the main clinical features of the cysts were retrieved from the requisition forms. The main microscopic features were recorded after reevaluation of all cases. Pubmed and Google Scholar electronic databases were searched with the key word “oral LEC”. Inclusion criteria were the microscopic confirmation of LEC diagnosis and the report at least two of three main clinical features (gender, age and cyst’s location). Results The 26 oral LECs represented 0.08% of 31,564 biopsies accessioned during the study period. They affected 25 patients, 14 females and 11 males with a mean age of 33.04±9.81 years. They appeared as smooth (92%) nodules, with soft (24%) or firm (76%) consistency and normal (28%), yellow to normal (20%), yellow (32%) or white (20%) hue, in the tongue (69.23%) or the floor of mouth (30.77%). They were covered by parakeratinized squamous (92.31%) or non-keratinized (7.69%) epithelium and contained desquamated epithelial cells, amorphous eosinophilic material and/or inflammatory cells (100%). The lymphoid tissue surrounded the cystic cavity partially (34.62%) or completely (65.38%), often in a follicular pattern with prominent germinal centers (53.85%). Literature review yielded 316 cases of oral LECs derived from 25 case reports, 3 case studies/retrospective studies with detailed information for each case and 7 studies with summarized data. Conclusions Oral LEC is a pathologic entity with discrete clinical presentation that is, however, commonly misdiagnosed in clinical practice as other, mostly benign, entities. Its pathogenesis remains obscure, as its clinicopathologic features are consistent with both theories suggested up to date. Key words:Oral lymphoepithelial cyst; developmental cyst; non odontogenic cyst; lymphoid tissue; oral tonsil. PMID:28936296

  7. A Qualitative Case Study of Reading-While-Listening to Audiobooks Simultaneously

    ERIC Educational Resources Information Center

    Linton, Sorena Christina

    2017-01-01

    This study was a qualitative, evaluative, multicase study to determine the educator perspectives on the barriers to using Reading While Listening (RWL) simultaneously to audiobooks and their corresponding printed material. The goal of this study was to understand whether RWL should be used more extensively, implemented into a set curriculum, and…

  8. Motivation in Technology Education among Novice and Technological Talents

    ERIC Educational Resources Information Center

    Autio, Ossi

    2010-01-01

    The purpose of this study was to determine the elements motivating comprehensive school students to study technology education. The research was carried out as a qualitative case study and the material was collected through individual theme interviews. The study group consisted of two different test groups: novice and technological talents. In…

  9. [Histopathological and immunohistochemical studies on mucous cysts].

    PubMed

    Kuroda, N

    1989-01-01

    The present study investigated the histopathology, histochemistry of mucopolysaccharides, and immunohistochemistry of oral mucous cysts. The materials were obtained from ninety cases that were histopathologically diagnosed as oral mucous cysts at the Department of Oral Pathology, Meikai University School of Dentistry. Mucopolysaccharide staining was done with PAS, alcian blue (AB, pH 2.5) and high iron diamine (HID). Immunohistochemical studies were focused on secretory component (SC), lactoferrin (Lf), alpha-amylase (Am), IgA, lysozyme (Ly), and keratin (Kr). The following results were obtained: 1. Histopathological findings. (1) Retention and/or retention-like type cysts occurred in was twenty-six cases and the extravasation type in sixty-four cases. (2) Cases showing epithelial lining of the cystic wall were only eight in number, and many cystic walls were contained granulation tissue (fifty cases). (3) As for inflammation of the cystic wall, the degree was slight, and infiltrated cells were mainly macrophages (so-called mucinophages) and lymphocytes. (4) Regarding adjoining salivary glands, acinar cells showed atrophic changes, and hypertrophy of mucous acinar cells was evident. Many ducts showed dilatation, and stromal connective tissue showed fibrosis and hyalinization. 2. Histochemical findings on mucopolysaccharides. (1) Mucous materials in cystic cavity, mucous acinar cells, and secretory materials in ductal lumens were intensely stained by PAS and AB. But stainability with AB was less than that with PAS staining. Serous acinar cells and ductal epithelium were negative to PAS and AB staining. (2) Stainability of the above with HID was less than at with PAS or AB. Cystic walls were not stained by HID. Mucous acinar cells reactive with HID were intensely stained, but the number of the positive cells was limited when compared with the numbers of PAS-and AB-positive cells. 3. Immunohistochemical findings. (1) As for mucous materials in the cystic cavity, reactions for Sc, Am, IgA, and Ly were all positive, whereas those for Lf and Kr were negative. (2) Staining of cystic walls was generally weak: the walls were negative for IgA, Ly and Kr showed and borderline or slightly positive for Sc, Lf, and Am. (3) Mucous acinar cells were negative for all markers examined in this study, but serous acinar cells and/or demilunes were markedly positive for Sc, Ly, and Am. (4) In ductal epithelial cells, Ly and Kr were negative, but IgA was borderline or slightly positive. Sc and Am gave intensely positive staining. (5) Secretory materials in ductal lumens, Sc were intensely positive for Lf, and Ly; slightly or moderately positive for IgA; and slightly positive or negative for Am.(ABSTRACT TRUNCATED AT 400 WORDS)

  10. Transformation of silicate gels during heat treatment in air and in argon - Spectroscopic studies

    NASA Astrophysics Data System (ADS)

    Rokita, M.; Mozgawa, W.; Adamczyk, A.

    2014-07-01

    The sol-gel method offers the possibility of obtaining silicate materials with different chemical compositions. When using TEOS or other organic precursor to silica capable of hydrolysis and poly-condensation, it is possible to use inorganic or organic precursors to produce other ingredients. This paper presents results of studying two series of silicate sols with the addition of calcium, in which the molar ratio of calcium to silicon was Ca/Si = x/(100 - x), where x was, respectively, 0-40 (x = 0-control sample). The resulting gels were subjected to heat treatment, wherein the heating was carried out simultaneously in air or in argon. To study the various stages of transformation of the gels, IR spectroscopy was used as the main research method to observe gradual disappearance of bands associated with bonds typical of organic materials and formation of bands characteristic of Si-O-Si bridging bonds. Due to the amorphous or fine crystalline nature of the resulting material, as confirmed in XRD studies, the different bands on the IR spectra were characterized by large full width at half maximum, hence an attempt was made to decompose the spectra into component bands. The analytic parameters of the resulting bands warranted the conclusion that there had been structural changes caused by the varying synthesis parameters. A comparison of the sol spectra after heat treatment in air and in argon at different temperatures showed a clear decrease in the full width at half maximum in the case of bands of samples with calcium content x ⩾ 30. The resulting spectra were compared with spectra of crystalline tobermorite, quartz and pseudowollastonite, which suggested the possibility of existence of areas with quartz-like ordering in the case of materials with calcium content x ⩾ 20 for the samples heated in argon and areas with pseudowollastonite-like ordering in the case of materials with calcium content x ⩾ 10 for the samples heated in air atmosphere. The conclusions drawn on the basis of infrared spectra were confirmed by XRD - prolonged heating of gels at 700 °C allowed us to obtain fine quartz and pseudowollastonite.

  11. OMC Compressor Case

    NASA Technical Reports Server (NTRS)

    Humphrey, W. Donald

    1997-01-01

    This report summarizes efforts expended in the development of an all-composite compressor case. Two pre-production units have been built, one utilizing V-CAP and one utilizing AFR-700B resin systems. Both units have been rig tested at elevated temperatures well above design limit loads. This report discusses the manufacturing processes, test results, and Finite Element Analysis performed. The V-CAP unit was funded by NASA-Lewis Research Center in 1994 under contract number NAS3- 27442 for Development of an All-Composite OMC Compressor Case. This contract was followed by an Air Force study in 1996 to build and identical unit using the AFR-700B resin system in place of the V-CAP system. The second compressor case was funded under U.S. Air Force contract F33615-93-D-5326, Advanced Materials for Aerospace Structures Special Studies (AMAS3), Delivery Order 0021 entitled "Advanced Polymeric Composite Materials and Structures Technology for Advanced High Temperature Gas Turbine Engines.' Initial studies using the V-CAP resin system were undertaken in 1993 under a NASA Lewis contract (NAS3-26829). A first prototype unit was developed in a joint program between Textron-Lycoming (now Allied Signal) and Brunswick (now Lincoln Composites). This unit included composite end closures using low density, high temperature molded end closures. The units was similar in size and shape to a titanium case currently used on the PT-21 0 engine and was funded as part of the integrated High Performance Turbine Engine Technology (EHPTET) initiative of DOD and NASA.

  12. Copyright Center Will Let Colleges Pay Blanket Fees to Reuse Print Material

    ERIC Educational Resources Information Center

    Read, Brock

    2007-01-01

    This article reports on an annual copyright license for colleges created by the Copyright Clearance Center, a nonprofit group that manages licenses for the reuse of published material, that will allow institutions to pay a blanket fee to use copyrighted material instead of securing the rights to such content on a case-by-case basis. The blanket…

  13. The Effectiveness of Substituting Locally Available Materials in Teaching Chemistry in Nigeria: A Case for Science Education in Developing Countries

    ERIC Educational Resources Information Center

    DomNwachukwu, Nkechi S.; DomNwachukwu, Chinaka S.

    2006-01-01

    This article investigates the effectiveness of improvising locally available materials for teaching chemistry in Nigeria, as a case for a culture of improvisation for teaching the sciences in developing countries. The scarcity and cost of imported materials for teaching science has remained a major challenge to teaching sciences in developing…

  14. Cholera outbreak in Homa Bay County, Kenya, 2015.

    PubMed

    Githuku, Jane Njoki; Boru, Waqo Gufu; Hall, Casey Daniel; Gura, Zeinab; Oyugi, Elvis; Kishimba, Rogath Saika; Semali, Innocent; Farhat, Ghada Nadim; Mattie Park, Meeyoung

    2017-01-01

    Cholera is among the re-emerging diseases in Kenya. Beginning in December 2014, a persistent outbreak occurred involving 29 out of the 47 countries. Homa Bay County in Western Kenya was among the first counties to report cholera cases from January to April 2015. This case study is based on an outbreak investigation conducted by FELTP residents in Homa Bay County in February 2015. It simulates an outbreak investigation including laboratory confirmation, active case finding, descriptive epidemiology and implementation of control measures. This case study is designed for the training of basic level field epidemiology trainees or any other health care workers working in public health-related fields. It can be administered in 2-3 hours. Used as adjunct training material, the case study provides the trainees with competencies in investigating an outbreak in preparation for the actual real-life experience of such outbreaks.

  15. X-ray photoelectron study of Si+ ion implanted polymers

    NASA Astrophysics Data System (ADS)

    Tsvetkova, T.; Balabanov, S.; Bischoff, L.; Krastev, V.; Stefanov, P.; Avramova, I.

    2010-11-01

    X-ray photoelectron spectroscopy was used to characterize different polymer materials implanted with low energy Si+ ions (E=30 keV, D= 1.1017 cm-2). Two kinds of polymers were studied - ultra-high-molecular-weight poly-ethylene (UHMWPE), and poly-methyl-methacrylate (PMMA). The non-implanted polymer materials show the expected variety of chemical bonds: carbon-carbon, carbon being three- and fourfold coordinated, and carbon-oxygen in the case of PMMA samples. The X-ray photoelectron and Raman spectra show that Si+ ion implantation leads to the introduction of additional disorder in the polymer material. The X-ray photoelectron spectra of the implanted polymers show that, in addition to already mentioned bonds, silicon creates new bonds with the host elements - Si-C and Si-O, together with additional Si dangling bonds as revealed by the valence band study of the implanted polymer materials.

  16. Fiber optic strain measurements using an optically-active polymer

    NASA Astrophysics Data System (ADS)

    Buckley, Leonard J.; Neumeister, Gary C.

    1992-03-01

    A study encompassing the use of an optically-active polymer as the strain-sensing medium in an organic matrix composite was performed. Several compounds were synthesized for use as the inner cladding material for silica fiber-optic cores. These materials include a diacetylene containing polyamide. It is possible to dynamically modify the optical properties of these materials through changes in applied strain or temperature. By doing so the characteristic absorption in the visible is reversibly shifted to a higher energy state. The polymer-coated fiber-optic cores were initially studied in epoxy resin. Additionally, one of the polyamide/diacetylene polymers was studied in a spin-fiber form consisting of 15 micron filaments assembled in multifilament tows. The most promising configuration and materials were then investigated further by embedding in graphite/epoxy composite laminates. In each case the shift in the visible absorption peak was monitored as a function of applied mechanical strain.

  17. A continuum mechanics-based musculo-mechanical model for esophageal transport

    NASA Astrophysics Data System (ADS)

    Kou, Wenjun; Griffith, Boyce E.; Pandolfino, John E.; Kahrilas, Peter J.; Patankar, Neelesh A.

    2017-11-01

    In this work, we extend our previous esophageal transport model using an immersed boundary (IB) method with discrete fiber-based structural model, to one using a continuum mechanics-based model that is approximated based on finite elements (IB-FE). To deal with the leakage of flow when the Lagrangian mesh becomes coarser than the fluid mesh, we employ adaptive interaction quadrature points to deal with Lagrangian-Eulerian interaction equations based on a previous work (Griffith and Luo [1]). In particular, we introduce a new anisotropic adaptive interaction quadrature rule. The new rule permits us to vary the interaction quadrature points not only at each time-step and element but also at different orientations per element. This helps to avoid the leakage issue without sacrificing the computational efficiency and accuracy in dealing with the interaction equations. For the material model, we extend our previous fiber-based model to a continuum-based model. We present formulations for general fiber-reinforced material models in the IB-FE framework. The new material model can handle non-linear elasticity and fiber-matrix interactions, and thus permits us to consider more realistic material behavior of biological tissues. To validate our method, we first study a case in which a three-dimensional short tube is dilated. Results on the pressure-displacement relationship and the stress distribution matches very well with those obtained from the implicit FE method. We remark that in our IB-FE case, the three-dimensional tube undergoes a very large deformation and the Lagrangian mesh-size becomes about 6 times of Eulerian mesh-size in the circumferential orientation. To validate the performance of the method in handling fiber-matrix material models, we perform a second study on dilating a long fiber-reinforced tube. Errors are small when we compare numerical solutions with analytical solutions. The technique is then applied to the problem of esophageal transport. We use two fiber-reinforced models for the esophageal tissue: a bi-linear model and an exponential model. We present three cases on esophageal transport that differ in the material model and the muscle fiber architecture. The overall transport features are consistent with those observed from the previous model. We remark that the continuum-based model can handle more realistic and complicated material behavior. This is demonstrated in our third case where a spatially varying fiber architecture is included based on experimental study. We find that this unique muscle fiber architecture could generate a so-called pressure transition zone, which is a luminal pressure pattern that is of clinical interest. This suggests an important role of muscle fiber architecture in esophageal transport.

  18. The Economics of Fishing.

    ERIC Educational Resources Information Center

    Stowell, G.H.

    1982-01-01

    Presents background material to help British high school students study the economics of the fishing industry. Students apply their knowledge of cost and revenue theory to a case study of a European Economic Community fisheries dispute which raises questions about government intervention in international resource allocation issues. (AM)

  19. "I Know This Is Supposed to Be More Like the Real World, but . . .": Student Perceptions of a PBL Implementation in an Undergraduate Materials Science Course

    ERIC Educational Resources Information Center

    Henry, Holly R.; Tawfik, Andrew A.; Jonassen, David H.; Winholtz, Robert A.; Khanna, Sanjeev

    2012-01-01

    This qualitative case study examines the initial implementation of a problem-based version of an undergraduate course in materials science for the purpose of identifying areas of improvement to the curriculum prior to a planned second implementation. The course was designed around problems that students work in small teams to solve under the…

  20. Autonomy in Materials Research: A Case Study in Carbon Nanotube Growth (Postprint)

    DTIC Science & Technology

    2016-10-21

    built an Autonomous Research System (ARES)—an autonomous research robot capable of first-of-its-kind closed-loop iterative materials experimentation...ARES exploits advances in autonomous robotics , artificial intelligence, data sciences, and high-throughput and in situ techniques, and is able to...roles of humans and autonomous research robots , and for human-machine partnering. We believe autonomous research robots like ARES constitute a

  1. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China

    PubMed Central

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-01-01

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase. PMID:27011196

  2. Material Flow Analysis as a Tool to improve Waste Management Systems: The Case of Austria.

    PubMed

    Allesch, Astrid; Brunner, Paul H

    2017-01-03

    This paper demonstrates the power of material flow analysis (MFA) for designing waste management (WM) systems and for supporting decisions with regards to given environmental and resource goals. Based on a comprehensive case study of a nationwide WM-system, advantages and drawbacks of a mass balance approach are discussed. Using the software STAN, a material flow system comprising all relevant inputs, stocks and outputs of wastes, products, residues, and emissions is established and quantified. Material balances on the level of goods and selected substances (C, Cd, Cr, Cu, Fe, Hg, N, Ni, P, Pb, Zn) are developed to characterize this WM-system. The MFA results serve well as a base for further assessments. Based on given goals, stakeholders engaged in this study selected the following seven criteria for evaluating their WM-system: (i) waste input into the system, (ii) export of waste (iii) gaseous emissions from waste treatment plants, (iv) long-term gaseous and liquid emissions from landfills, (v) waste being recycled, (vi) waste for energy recovery, (vii) total waste landfilled. By scenario analysis, strengths and weaknesses of different measures were identified. The results reveal the benefits of a mass balance approach due to redundancy, data consistency, and transparency for optimization, design, and decision making in WM.

  3. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China.

    PubMed

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-03-22

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase.

  4. George Orwell's Animal Farm: a case study in leadership/management for undergraduate nursing students.

    PubMed

    Metcalf, James A

    2005-07-01

    Many BSN curricula require a "leadership and management" course. At George Mason University, that course is Leadership and Management in Nursing and Health Science. This article describes how George Orwell's classic novel Animal Farm was used as a case study in leadership and management. This exercise complemented the traditional course material, united the class in a common intellectual exercise, and fostered creative thinking. A nursing student, Anne Lord, offers reaction to the assignment as a signed "In-Box" exemplar.

  5. Brain tumors in children and occupational exposure of parents.

    PubMed

    Peters, F M; Preston-Martin, S; Yu, M C

    1981-07-10

    Ninety-two cases of brain tumor in children less than 10 years old were compared with 92 matched controls for parental occupational history. Cases were more likely than controls to show material occupations involving chemical exposure, paternal occupations involving solvents, and employment of father in the aircraft industry. These three factors were not affected by adjustment for the potential confounding variables examined in this study.

  6. Popular Video Cartoons and Associated Branded Toys in Teaching English to Very Young Learners: A Case Study

    ERIC Educational Resources Information Center

    Prosic-Santovac, Danijela

    2017-01-01

    When teaching foreign languages to very young learners, motivation is an issue that needs to be taken into account even more than in the case of any other age group. Teaching materials and students' textbooks used in schools and preschools, however carefully crafted, often fail to cater for the genuine interests of children and to invoke intrinsic…

  7. Orchestrating Semiotic Leaps from Tacit to Cultural Quantitative Reasoning--The Case of Anticipating Experimental Outcomes of a Quasi-Binomial Random Generator

    ERIC Educational Resources Information Center

    Abrahamson, Dor

    2009-01-01

    This article reports on a case study from a design-based research project that investigated how students make sense of the disciplinary tools they are taught to use, and specifically, what personal, interpersonal, and material resources support this process. The probability topic of binomial distribution was selected due to robust documentation of…

  8. Combining Advanced Turbulent Mixing and Combustion Models with Advanced Multi-Phase CFD Code to Simulate Detonation and Post-Detonation Bio-Agent Mixing and Destruction

    DTIC Science & Technology

    2017-10-01

    perturbations in the energetic material to study their effects on the blast wave formation. The last case also makes use of the same PBX, however, the...configuration, Case A: Spore cloud located on the top of the charge at an angle 45 degree, Case B: Spore cloud located at an angle 45 degree from the charge...theoretical validation. The first is the Sedov case where the pressure decay and blast wave front are validated based on analytical solutions. In this test

  9. Integrating remediation and resource recovery: On the economic conditions of landfill mining.

    PubMed

    Frändegård, Per; Krook, Joakim; Svensson, Niclas

    2015-08-01

    This article analyzes the economic potential of integrating material separation and resource recovery into a landfill remediation project, and discusses the result and the largest impact factors. The analysis is done using a direct costs/revenues approach and the stochastic uncertainties are handled using Monte Carlo simulation. Two remediation scenarios are applied to a hypothetical landfill. One scenario includes only remediation, while the second scenario adds resource recovery to the remediation project. Moreover, the second scenario is divided into two cases, case A and B. In case A, the landfill tax needs to be paid for re-deposited material and the landfill holder does not own a combined heat and power plant (CHP), which leads to disposal costs in the form of gate fees. In case B, the landfill tax is waived on the re-deposited material and the landfill holder owns its own CHP. Results show that the remediation project in the first scenario costs about €23/ton. Adding resource recovery as in case A worsens the result to -€36/ton, while for case B the result improves to -€14/ton. This shows the importance of landfill tax and the access to a CHP. Other important factors for the result are the material composition in the landfill, the efficiency of the separation technology used, and the price of the saleable material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Phase 2 STS new user development program. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Mcdowell, J. R.

    1976-01-01

    A methodology for developing new users for STS other than NASA and DoD, thereby maximizing the use of the STS system was developed. The approach to user development, reflected in the implementation plan, and attendant informational material to be used were evaluated by conducting a series of test cases with selected user organizations. These test case organizations were, in effect, used as consultants to evaluate the effectiveness, the needs, the completeness, and the adequacy of the user development approach and informational material. The selection of the test cases provided a variety of potential STS users covering industry, other government agencies, and the educational sector. The test cases covered various use areas and provided a mix of user organization types. A summary of the actual test cases conducted is given. The conduct of the test cases verified the general approach of the implementation plan, the validity of the user development strategy prepared for each test case organization and the effectiveness of the STS basic and user customized informational material.

  11. The same teacher, the same curriculum materials, different schools: What is the enacted curriculum?

    NASA Astrophysics Data System (ADS)

    Eisenmann, Tammy

    This research examines how the same teacher implements the same curriculum material in two different schools. The aim of the study is to examine how the enacted algebra curriculum may change when the same teacher enacts the same written curriculum materials in different classes. This research comprises two case studies. Each case examines one teacher who taught the beginning of the mathematical topic "equivalent algebraic expressions", to two 7th grade classes from different schools. The same textbook was used in all four classes. The data collected includes: 1. Observations: 25930 lessons throughout the school year in each of the participating classes; Other mathematics classes in each of the schools; Other non9mathematics classes in the participating classes. A total of 130 lessons were observed. The observations included continuous observations of the teaching of "equivalent algebraic expressions" (15919 lessons) in each class. These observations are the main data source of this research; 2. Interviews with the teachers; 3. Informal conversations; and 4. Field notes. The data was analyzed both through quantitative and qualitative analysis. The research focuses on the following two aspects of the enacted curriculum: implementation of the recommendation that appeared in the curriculum materials and the types of algebraic activity that the students were exposed to during the teaching of the mathematical topic. Kieran's framework (Kieran, 1996, 2004), which distinguishes between three types of algebraic activities 9 generational, transformational and global/meta9level 9 was employed for the examination of the algebraic activities. Comparisons were made for two aspects of the research: between the enacted curriculum in each of the classes and the curriculum materials; and between each of the classes taught by same teacher. It was found that in case study 1, that examined teacher Sara and schools Carmel and Tavor -- most of the recommendations for instruction that appeared in the curriculum materials, were implemented: The students were exposed to the main mathematical subjects/ideas and the mathematical sequence that appeared in the curriculum materials; the lesson structure was similar to the recommended structure, and did not include work on assignments that were not recommended in the curriculum materials. In spite of the similarities in each of the classes, and the curriculum materials, and between the two classes -- a few differences were found, mainly while comparing the enactment in Tavor versus the recommendations in the curriculum materials and the enactment in Carmel. Examination of the algebraic types of activities that the students were exposed to in Carmel and Tavor schools throughout the school year shows that, although the students in the two schools were not required to deal with a similar number of assignments and tasks, in both schools they were exposed to the three types of algebraic activities in similar distribution as appear in the curriculum materials. The focus on the algebraic types of activities exposed to during the whole class work, shows that a significantly lesser percentage of global/meta9level activities was enacted in Tavor. In Tavor, teacher Sara omitted global/meta level activities that appear in the curriculum materials and in addition, there were several cases in which the same assignment/task was enacted in Carmel as a global/meta9level activity but was not enacted in Tavor. In case study 2, which included teacher Rebecca and schools Gamla and Arbel, not all the recommendations in the curriculum material were enacted. Indeed, in both classes the main mathematics subjects/ideas intended for this topic according to the curriculum materials were presented to the students, and the topic was taught according to the mathematical sequence that appeared in the curriculum materials, however in both classes the lesson structures were different from the intended structure -- unintended assignments were enacted, and some of the assignments were enacted not according to their purpose (for example, an assignment that was intended for group work was given as homework). These differences were found in comparison of each of the classes to the curriculum materials and in comparison between Gamla and Arbel. Examination of the algebraic types of activities that the students were exposed to in both classes throughout the school year as well as in the whole class -- shows differences originating from both transformational and global/meta9level algebraic activities. It was found that in Gamla more global/meta9level activities were enacted, as compared to the curriculum materials and the enactment in Arbel. In Arbel, however, emphasis was given to transformational activities as compared to the curriculum materials and enactment in Gamla. In addition it was found that there is also a difference in the way both teachers, Sara and Rebecca, perceived the curriculum materials, and that this perception is expressed in the different way each of them used the curriculum materials in their classes. (Abstract shortened by UMI.)

  12. Raman Mapping for the Investigation of Nano-phased Materials

    NASA Astrophysics Data System (ADS)

    Gouadec, G.; Bellot-Gurlet, L.; Baron, D.; Colomban, Ph.

    Nanosized and nanophased materials exhibit special properties. First they offer a good compromise between the high density of chemical bonds by unit volume, needed for good mechanical properties and the homogeneity of amorphous materials that prevents crack initiation. Second, interfaces are in very high concentration and they have a strong influence on many electrical and redox properties. The analysis of nanophased, low crystallinity materials is not straigtforward. The recording of Raman spectra with a geometric resolution close to 0.5 \\upmu {text{ m}^3} and the deep understanding of the Raman signature allow to locate the different nanophases and to predict the properties of the material. Case studies are discussed: advanced polymer fibres, ceramic fibres and composites, textured piezoelectric ceramics and corroded (ancient) steel.

  13. In vitro and in vivo evidence of the cytotoxic and genotoxic effects of metal ions released by orthodontic appliances: A review.

    PubMed

    Martín-Cameán, Ana; Jos, Ángeles; Mellado-García, Pilar; Iglesias-Linares, Alejandro; Solano, Enrique; Cameán, Ana M

    2015-07-01

    Intraoral fixed orthodontic appliances are frequently used in the clinical practice of dentistry. They are made from alloys containing different metals at various percentages. The use of these appliances leads to the long-term exposure of patients to these materials, and the potential toxic effects of this exposure raises concerns about patient safety. Thus, the biocompatibility (corrosion behaviour and toxicity) of these materials has to be evaluated prior to clinical use. In the present report, the most recent studies in the scientific literature examining metal ion release from orthodontic appliances and the toxic effects of these ions have been reviewed with a special focus on cytotoxicity and genotoxicity. Previous studies suggest that a case-by-case safety evaluation is required to take into account the increasing variability of materials, their composition and the manufacturing processes. Moreover, in vivo toxicity studies in regard to metal release, cytotoxicity and genotoxicity are still scarce. Therefore, in vitro and in vivo monitoring studies are needed to establish cause-effect relationships between metal ion release and biomarkers of cytotoxicity and genotoxicity. Further investigations could be performed to elucidate the toxic mechanisms involved in the observed effects with a special emphasis on oxidative damage. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Optical coherence tomography based imaging of dental demineralisation and cavity restoration in 840 nm and 1310 nm wavelength regions

    NASA Astrophysics Data System (ADS)

    Damodaran, Vani; Rao, Suresh Ranga; Vasa, Nilesh J.

    2016-08-01

    In this paper, a study of in-house built optical coherence tomography (OCT) system with a wavelength of 840 nm for imaging of dental caries, progress in demineralisation and cavity restoration is presented. The caries when imaged with the 840 nm OCT system showed minute demineralisation in the order of 5 μm. The OCT system was also proposed to study the growth of lesion and this was demonstrated by artificially inducing caries with a demineralisation solution of pH 4.8. The progress of carious lesion to a depth of about 50-60 μm after 60 hours of demineralisation was clearly observed with the 840 nm OCT system. The tooth samples were subjected to accelerated demineralisation condition at pH of approximately 2.3 to study the adverse effects and the onset of cavity formation was clearly observed. The restoration of cavity was also studied by employing different restorative materials (filled and unfilled). In the case of restoration without filler material (unfilled), the restoration boundaries were clearly observed. Overall, results were comparable with that of the widely used 1310 nm OCT system. In the case of restoration with filler material, the 1310 nm OCT imaging displayed better imaging capacity due to lower scattering than 840 nm imaging.

  15. Evaluation of municipal solid waste management performance by material flow analysis: Theoretical approach and case study.

    PubMed

    Zaccariello, Lucio; Cremiato, Raffaele; Mastellone, Maria Laura

    2015-10-01

    The main role of a waste management plan is to define which is the combination of waste management strategies and method needed to collect and manage the waste in such a way to ensure a given set of targets is reached. Objectives have to be sustainable and realistic, consistent with the environmental policies and regulations and monitored to verify the progressive achievement of the given targets. To get the aim, the setting up and quantification of indicators can allow the measurement of efficiency of a waste management system. The quantification of efficiency indicators requires the developing of a material flow analysis over the system boundary, from waste collection to secondary materials selling, processing and disposal. The material flow analysis has been carried out with reference to a case study for which a reliable, time- and site-specific database was available. The material flow analysis allowed the evaluation of the amount of materials sent to recycling, to landfilling and to waste-to-energy, by highlighting that the sorting of residual waste can further increase the secondary materials amount. The utilisation of energy recovery to treat the low-grade waste allows the maximisation of waste diversion from landfill with a low production of hazardous ash. A preliminary economic balance has been carried out to define the gate fee of the waste management system that was in the range of 84-145 € t(-1) without including the separate collection cost. The cost of door-by-door separate collection, designed to ensure the collection of five separate streams, resulted in 250 € t(-1) ±30%. © The Author(s) 2015.

  16. Toward Eco Product Development with Qualitative and CAE Design Process - Case Study of Flame Guiding Module

    NASA Astrophysics Data System (ADS)

    Chen, W. L.; Chao, F. L.

    2018-04-01

    Sustainable products become increasingly important for company in addressing eco-performance to satisfy global environmental regulations. Case study of flame guiding module reviewed design process and concerns related to the torch design. For enhancing flame height, the torch was embedded with an airflow guidance structure. The design process and design methodologies were investigated as an eco-design case study. Combine qualitative and CAE simulation were proposed to fulfil its main and auxiliary functions including reduction of impact during use. The design guidelines help prevent mistake arrangements, CAE helps understand combustion phenomenon. The flow field simulation enables fine tune of geometric design. Functional test and measurement are carried out to confirm the product features. On Eco-performance, we choose 5 items for evaluation the status of previous and redesign module, namely function need, low impact material, few manufacturing steps, low energy consumption, and safety. The radar diagram indicates that eco-performance of redesign module is better. Life cycle assessment calculated the carbon footprint of the manufacturing and processing stage with Eco-it. By using recycled steel in the flame module, it reduces raw material stage carbon footprint significantly.

  17. Chronic lymphatic leukaemia and engine exhausts, fresh wood, and DDT: a case-referent study.

    PubMed Central

    Flodin, U; Fredriksson, M; Persson, B; Axelson, O

    1988-01-01

    The effect of potential risk factors for chronic lymphatic leukaemia was evaluated in a case-referent study encompassing 111 cases and 431 randomised referents, all alive. Information on exposure was obtained by questionnaires posted to the subjects. Crude rate ratios were increased for occupational exposure to solvents. DDT, engine exhausts, fresh wood (lumberjacks, paper pulp workers, and sawmill workers, for example) and also in farming. Further analysis of the material by means of the Miettinen confounder score technique reduced the number of rate ratios significantly exceeding unity to encompass only occupational exposure to engine exhaust, fresh wood, DDT, and contact with horses. PMID:2449239

  18. The 'relics of Joan of Arc': a forensic multidisciplinary analysis.

    PubMed

    Charlier, P; Poupon, J; Eb, A; De Mazancourt, P; Gilbert, T; Huynh-Charlier, I; Loublier, Y; Verhille, A M; Moulheirat, C; Patou-Mathis, M; Robbiola, L; Montagut, R; Masson, F; Etcheberry, A; Brun, L; Willerslev, E; de la Grandmaison, G Lorin; Durigon, M

    2010-01-30

    Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques. In the case of the so-called 'Joan of Arc's relics' (a group of bone and archaeological remains known as the 'Bottle of Chinon'), 14 specialists analysed the samples such as a cadaver X of carbonised aspect: forensic anthropologist, medical examiners, pathologists, geneticists, radiologist, biochemists, palynologists, zoologist and archaeologist. Materials, methods and results of this study are presented here. This study aims to offer an exploitable methodology for the modern medico-legal cases of small quantities of human bones of carbonised aspect. 2009 Elsevier Ireland Ltd. All rights reserved.

  19. Evaluation Report of the Double Wall Air Inflated MUST Shelter Made from Three Dimensional Fabric

    DTIC Science & Technology

    1975-10-22

    II Natick laboratory Test Results on Spray Coated 3-D Woven Fabric iWST Shelter Casing Material ......... 29 11 3-D Casing Fabric D1mensions, as Woven...of yarns shoi . be achieved before spraying. 3.1.3 The casing surface should be inspected afhir each of the first several spray coats for pinholes in...Coated Fabric Casing Material After two days of drying time, a three-foot-wide portion was cut off from one end of a sprayed casing . Part of this coated

  20. Quality by design for herbal drugs: a feedforward control strategy and an approach to define the acceptable ranges of critical quality attributes.

    PubMed

    Yan, Binjun; Li, Yao; Guo, Zhengtai; Qu, Haibin

    2014-01-01

    The concept of quality by design (QbD) has been widely accepted and applied in the pharmaceutical manufacturing industry. There are still two key issues to be addressed in the implementation of QbD for herbal drugs. The first issue is the quality variation of herbal raw materials and the second issue is the difficulty in defining the acceptable ranges of critical quality attributes (CQAs). To propose a feedforward control strategy and a method for defining the acceptable ranges of CQAs for the two issues. In the case study of the ethanol precipitation process of Danshen (Radix Salvia miltiorrhiza) injection, regression models linking input material attributes and process parameters to CQAs were built first and an optimisation model for calculating the best process parameters according to the input materials was established. Then, the feasible material space was defined and the acceptable ranges of CQAs for the previous process were determined. In the case study, satisfactory regression models were built with cross-validated regression coefficients (Q(2) ) all above 91 %. The feedforward control strategy was applied successfully to compensate the quality variation of the input materials, which was able to control the CQAs in the 90-110 % ranges of the desired values. In addition, the feasible material space for the ethanol precipitation process was built successfully, which showed the acceptable ranges of the CQAs for the concentration process. The proposed methodology can help to promote the implementation of QbD for herbal drugs. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Multidisciplinary tailoring of hot composite structures

    NASA Technical Reports Server (NTRS)

    Singhal, Surendra N.; Chamis, Christos C.

    1993-01-01

    A computational simulation procedure is described for multidisciplinary analysis and tailoring of layered multi-material hot composite engine structural components subjected to simultaneous multiple discipline-specific thermal, structural, vibration, and acoustic loads. The effect of aggressive environments is also simulated. The simulation is based on a three-dimensional finite element analysis technique in conjunction with structural mechanics codes, thermal/acoustic analysis methods, and tailoring procedures. The integrated multidisciplinary simulation procedure is general-purpose including the coupled effects of nonlinearities in structure geometry, material, loading, and environmental complexities. The composite material behavior is assessed at all composite scales, i.e., laminate/ply/constituents (fiber/matrix), via a nonlinear material characterization hygro-thermo-mechanical model. Sample tailoring cases exhibiting nonlinear material/loading/environmental behavior of aircraft engine fan blades, are presented. The various multidisciplinary loads lead to different tailored designs, even those competing with each other, as in the case of minimum material cost versus minimum structure weight and in the case of minimum vibration frequency versus minimum acoustic noise.

  2. Non-accident release of hazmat from railroad tank cars : training issues

    DOT National Transportation Integrated Search

    1999-07-01

    This report presents the results of a study to determine the extent to which written materials used in training railroad tank car HAZMAT loaders are consistent with the reading skills of the trainees. Data from four case study sites was used to condu...

  3. A Challenging Case of Acute Mercury Toxicity

    PubMed Central

    Alghoula, Faysal; Holewinski, Christopher

    2018-01-01

    Background Mercury exists in multiple forms: elemental, organic, and inorganic. Its toxic manifestations depend on the type and magnitude of exposure. The role of colonoscopic decompression in acute mercury toxicity is still unclear. We present a case of acute elemental mercury toxicity secondary to mercury ingestion, which markedly improved with colonoscopic decompression. Clinical Case A 54-year-old male presented to the ED five days after ingesting five ounces (148 cubic centimeters) of elemental mercury. Examination was only significant for a distended abdomen. Labs showed elevated serum and urine mercury levels. An abdominal radiograph showed radiopaque material throughout the colon. Succimer and laxatives were initiated. The patient had recurrent bowel movements, and serial radiographs showed interval decrease of mercury in the descending colon with interval increase in the cecum and ascending colon. Colonoscopic decompression was done successfully. The colon was evacuated, and a repeat radiograph showed decreased hyperdense material in the colon. Three months later, a repeat radiograph showed no hyperdense material in the colon. Conclusion Ingested elemental mercury can be retained in the colon. Although there are no established guidelines for colonoscopic decompression, our patient showed significant improvement. We believe further studies on this subject are needed to guide management practices. PMID:29559996

  4. Life Cycle Assessment of concrete manufacturing in small isolated states: the case of Cyprus

    NASA Astrophysics Data System (ADS)

    Chrysostomou, Chrystalla; Kylili, Angeliki; Nicolaides, Demetris; Fokaides, Paris A.

    2017-10-01

    Life Cycle Assessment (LCA) is an effective and valuable methodology for identifying the holistic sustainable behaviour of materials and products. It is also useful in analysing the impact a structure has over the course of its life cycle. Currently, there is no sufficient knowhow regarding the life cycle performance of building materials used in the case of small isolated states. This study focuses on the LCA of the production of concrete for the investigation of its environmental impact in isolated island states, using the case of Cyprus as an example. Four different scenarios for the production of 1 tonne of concrete are examined: (i) manufacturing of concrete by transporting raw materials from different locations around the island, (ii) manufacturing of concrete using alternative energy resources, (iii) manufacturing of concrete with reduced transportation needs, and (iv) on-site manufacturing of concrete. The results, in terms of environmental impacts of concrete produced, indicated that the use of renewable electricity instead of fossil-fuelled electricity in isolated states can drastically improve the environmental performance of the end product. Also, the minimisation of transportation distances and the use of locally available resources can also affect, to a degree, the environmental impact of concrete production.

  5. Soft lubrication: The elastohydrodynamics of nonconforming and conforming contacts

    NASA Astrophysics Data System (ADS)

    Skotheim, J. M.; Mahadevan, L.

    2005-09-01

    We study the lubrication of fluid-immersed soft interfaces and show that elastic deformation couples tangential and normal forces and thus generates lift. We consider materials that deform easily, due to either geometry (e.g., a shell) or constitutive properties (e.g., a gel or a rubber), so that the effects of pressure and temperature on the fluid properties may be neglected. Four different system geometries are considered: a rigid cylinder moving parallel to a soft layer coating a rigid substrate; a soft cylinder moving parallel to a rigid substrate; a cylindrical shell moving parallel to a rigid substrate; and finally a cylindrical conforming journal bearing coated with a thin soft layer. In addition, for the particular case of a soft layer coating a rigid substrate, we consider both elastic and poroelastic material responses. For all these cases, we find the same generic behavior: there is an optimal combination of geometric and material parameters that maximizes the dimensionless normal force as a function of the softness parameter η =hydrodynamicpressure/elasticstiffness=surfacedeflection/gapthickness, which characterizes the fluid-induced deformation of the interface. The corresponding cases for a spherical slider are treated using scaling concepts.

  6. Coupled heat transfer model and experiment study of semitransparent barrier materials in aerothermal environment

    NASA Astrophysics Data System (ADS)

    Wang, Da-Lin; Qi, Hong

    Semi-transparent materials (such as IR optical windows) are widely used for heat protection or transfer, temperature and image measurement, and safety in energy , space, military, and information technology applications. They are used, for instance, ceramic coatings for thermal barriers of spacecrafts or gas turbine blades, and thermal image observation under extreme or some dangerous environments. In this paper, the coupled conduction and radiation heat transfer model is established to describe temperature distribution of semitransparent thermal barrier medium within the aerothermal environment. In order to investigate this numerical model, one semi-transparent sample with black coating was considered, and photothermal properties were measured. At last, Finite Volume Method (FVM) was used to solve the coupled model, and the temperature responses from the sample surfaces were obtained. In addition, experiment study was also taken into account. In the present experiment, aerodynamic heat flux was simulated by one electrical heater, and two experiment cases were designed in terms of the duration of aerodynamic heating. One case is that the heater irradiates one surface of the sample continually until the other surface temperature up to constant, and the other case is that the heater works only 130 s. The surface temperature responses of these two cases were recorded. Finally, FVM model of the coupling conduction-radiation heat transfer was validated based on the experiment study with relative error less than 5%.

  7. Fiber-modified polyurethane foam for ballistic protection

    NASA Technical Reports Server (NTRS)

    Fish, R. H.; Parker, J. A.; Rosser, R. W.

    1975-01-01

    Closed-cell, semirigid, fiber-loaded, self-extinguishing polyurethane foam material fills voids around fuel cells in aircraft. Material prevents leakage of fuel and spreading of fire in case of ballistic incendiary impact. It also protects fuel cell in case of exterior fire.

  8. Recruitment Strategies and Costs Associated with Community-Based Research in a Mexican-Origin Population

    ERIC Educational Resources Information Center

    Mendez-Luck, Carolyn A.; Trejo, Laura; Miranda, Jeanne; Jimenez, Elizabeth; Quiter, Elaine S.; Mangione, Carol M.

    2011-01-01

    Purpose: We describe the recruitment strategies and personnel and materials costs associated with two community-based research studies in a Mexican-origin population. We also highlight the role that academic-community partnerships played in the outreach and recruitment process for our studies. We reviewed study documents using case study…

  9. Symbolic Leadership and Leadership Culture in One Unified Comprehensive School in Finland

    ERIC Educational Resources Information Center

    Lahtero, Tapio Juhani; Risku, Mika

    2012-01-01

    The research presented in this article is a description of the symbolic leadership and leadership culture in one unified comprehensive school in Finland. The study is a phenomenological qualitative case study based on triangulation. Leadership is studied through its functional, verbal and material dimensions. Leadership culture is regarded as one…

  10. Biomimicry in Product Design through Materials Selection and Computer Aided Engineering

    NASA Astrophysics Data System (ADS)

    Alexandridis, G.; Tzetzis, D.; Kyratsis, P.

    2016-11-01

    The aim of this study is to demonstrate a 7-step methodology that describes the way nature can act as a source of inspiration for the design and the development of a product. Furthermore, it suggests special computerized tools and methods for the product optimization regarding its environmental impact i.e. material selection, production methods. For validation purposes, a garden chaise lounge that imitates the form of a scorpion was developed as a result for the case study and the presentation of the current methodology.

  11. Identification of approximately duplicate material records in ERP systems

    NASA Astrophysics Data System (ADS)

    Zong, Wei; Wu, Feng; Chu, Lap-Keung; Sculli, Domenic

    2017-03-01

    The quality of master data is crucial for the accurate functioning of the various modules of an enterprise resource planning (ERP) system. This study addresses specific data problems arising from the generation of approximately duplicate material records in ERP databases. Such problems are mainly due to the firm's lack of unique and global identifiers for the material records, and to the arbitrary assignment of alternative names for the same material by various users. Traditional duplicate detection methods are ineffective in identifying such approximately duplicate material records because these methods typically rely on string comparisons of each field. To address this problem, a machine learning-based framework is developed to recognise semantic similarity between strings and to further identify and reunify approximately duplicate material records - a process referred to as de-duplication in this article. First, the keywords of the material records are extracted to form vectors of discriminating words. Second, a machine learning method using a probabilistic neural network is applied to determine the semantic similarity between these material records. The approach was evaluated using data from a real case study. The test results indicate that the proposed method outperforms traditional algorithms in identifying approximately duplicate material records.

  12. A System for True and False Memory Prediction Based on 2D and 3D Educational Contents and EEG Brain Signals.

    PubMed

    Bamatraf, Saeed; Hussain, Muhammad; Aboalsamh, Hatim; Qazi, Emad-Ul-Haq; Malik, Amir Saeed; Amin, Hafeez Ullah; Mathkour, Hassan; Muhammad, Ghulam; Imran, Hafiz Muhammad

    2016-01-01

    We studied the impact of 2D and 3D educational contents on learning and memory recall using electroencephalography (EEG) brain signals. For this purpose, we adopted a classification approach that predicts true and false memories in case of both short term memory (STM) and long term memory (LTM) and helps to decide whether there is a difference between the impact of 2D and 3D educational contents. In this approach, EEG brain signals are converted into topomaps and then discriminative features are extracted from them and finally support vector machine (SVM) which is employed to predict brain states. For data collection, half of sixty-eight healthy individuals watched the learning material in 2D format whereas the rest watched the same material in 3D format. After learning task, memory recall tasks were performed after 30 minutes (STM) and two months (LTM), and EEG signals were recorded. In case of STM, 97.5% prediction accuracy was achieved for 3D and 96.6% for 2D and, in case of LTM, it was 100% for both 2D and 3D. The statistical analysis of the results suggested that for learning and memory recall both 2D and 3D materials do not have much difference in case of STM and LTM.

  13. A System for True and False Memory Prediction Based on 2D and 3D Educational Contents and EEG Brain Signals

    PubMed Central

    2016-01-01

    We studied the impact of 2D and 3D educational contents on learning and memory recall using electroencephalography (EEG) brain signals. For this purpose, we adopted a classification approach that predicts true and false memories in case of both short term memory (STM) and long term memory (LTM) and helps to decide whether there is a difference between the impact of 2D and 3D educational contents. In this approach, EEG brain signals are converted into topomaps and then discriminative features are extracted from them and finally support vector machine (SVM) which is employed to predict brain states. For data collection, half of sixty-eight healthy individuals watched the learning material in 2D format whereas the rest watched the same material in 3D format. After learning task, memory recall tasks were performed after 30 minutes (STM) and two months (LTM), and EEG signals were recorded. In case of STM, 97.5% prediction accuracy was achieved for 3D and 96.6% for 2D and, in case of LTM, it was 100% for both 2D and 3D. The statistical analysis of the results suggested that for learning and memory recall both 2D and 3D materials do not have much difference in case of STM and LTM. PMID:26819593

  14. Finite element analysis of fretting contact for nonhomogenous materials

    NASA Astrophysics Data System (ADS)

    Korkmaz, Y. M.; Coker, D.

    2018-01-01

    Fretting problem arises in the case of relatively small sliding motion between contacting surfaces. Fatigue life of the components that are in contact with each other, especially in rotorcraft may be significantly reduced due to fretting. The purpose of this study is to investigate material inhomogeneity near the contact region on the fretting problem in a cylindrical on flat contact configuration. A finite element (FE) model was constructed by using commercial finite element package ABAQUSTMto study partial sliding and stress concentrations. In order to investigate the effect of material inhomogeneity, the fretting contact is analyzed by introducing voids near the contact region. The void size and an array of voids is introduced into the substrate. The results are compared in terms of pressure, shear traction, tangential stress magnitudes and relative slip between the contacting materials.

  15. Analysis of the embodied and operational energy: Study of a suburban house in Athens, Greece

    NASA Astrophysics Data System (ADS)

    Ghiata, Maria

    Operational energy can establish how successful a building is, in terms of environmentally 'considerate' design. Though embodied energy of construction materials also comprises an important indicator of the environmental impact of the material, the construction industry does not really promote it as such. This report enhances the significance of embodied energy and its relationship to operational energy (energy in use). Since buildings are becoming less energy demanding, operational energy will be decreasing, so that embodied energy will be gaining ground in the attempt to protect the environment. By the use of an 'environmentally friendly' house as a case study, it was proven that, though changes of the wall, floor, and insulation materials can take place, the operational energy does not change. What is greatly affected is the embodied energy of these construction materials.

  16. Cytomorphology of cervicovaginal melanoma: ThinPrep versus conventional Papanicolaou tests.

    PubMed

    Setia, Namrata; Goulart, Robert A; Leiman, Gladywn; Otis, Christopher N; Modem, Rukmini; Pantanowtiz, Liron

    2010-12-31

    Primary cervicovaginal melanoma is a rare malignancy associated with a high risk of recurrence. Prior studies discussing the cytomorphology of cervicovaginal melanoma have been based primarily on review of conventional Papanicolaou (Pap) smears. The aim of this study was to evaluate cervicovaginal melanomas identified in liquid-based Pap tests, in comparison with features seen on conventional Pap smear preparation. Cases of cervicovaginal melanoma identified on Pap tests with concurrent or subsequent histopathologic confirmation were collected from the Baystate Medical Center cytopathology files and personal archives of the authors over a total period of 34 years. All cytopathology (n = 6) and the available histology slides (n = 5) were reviewed. Cases were analyzed regarding clinical, histopathologic and cytomorphological findings. A total of six cases with invasive cervicovaginal melanoma diagnosed on Pap tests were identified. Most patients were postmenopausal with contact bleeding, correlating with surface ulceration (identified in biopsy/excision material in 5/5 cases). Most cases had deeply invasive tumors (5/5: modified Breslow's thickness > 5 mm and Chung's level of invasion IV/V). Pap tests included four ThinPrep and two conventional smears. Overall, ThinPrep Pap tests exhibited a higher ratio of tumor cells to background squamous cells. While all Pap tests were bloodstained, tumor diathesis was prominent only within conventional smears. Melanoma cells were present both as clusters and scattered single cells in each Pap test type. Both the preparations contained epithelioid tumor cells, whereas spindled tumor cells were seen in only two ThinPrep cases. Prominent nucleoli and binucleation of tumor cells were seen in both the preparations. Melanin pigment was identified in only ThinPrep (3/4) cases and nuclear pseudo-inclusions in one conventional Pap smear. Cell blocks were made in three ThinPrep cases and immunocytochemistry (S-100, HMB45, Melan-A) performed on additional vial material (one ThinPrep slide and one cell block) was immunoreactive in melanoma cells. Primary cervicovaginal melanoma, a rare malignancy seen predominantly in postmenopausal women, may be successfully diagnosed in either ThinPrep Pap tests or conventional Pap smears. While ThinPrep Pap tests did not demonstrate morphological advantage over conventional smears, liquid-based cytology specimens did provide additional material for cellblock preparation and immunocytochemical evaluation in a subset of cases.

  17. Perceptions of Pedagogical Formation Students about Web 2.0 Tools and Educational Practices

    ERIC Educational Resources Information Center

    Avci Yücel, Ümmühan

    2017-01-01

    This study aims to examine pedagogical formation students' perceptions about Web 2.0 tools and educational practices. A case study approach forms the methodological framework of this study. This study was conducted with 42 pedagogical formation students of an Instructional Technology and Material Design course during the 2014-2015 spring semester.…

  18. Organizational influence on the occurrence of work accidents involving exposure to biological material.

    PubMed

    Marziale, Maria Helena Palucci; Rocha, Fernanda Ludmilla Rossi; Robazzi, Maria Lúcia do Carmo Cruz; Cenzi, Camila Maria; dos Santos, Heloisa Ehmke Cardoso; Trovó, Marli Elisa Mendes

    2013-01-01

    to analyze work accidents involving exposure to biological materials which took place among personnel working in nursing and to evaluate the influence of the organizational culture on the occurrence of these accidents. a retrospective, analytical study, carried out in two stages in a hospital that was part of the Network for the Prevention of Work Accidents. The first stage involved the analysis of the characteristics of the work accidents involving exposure to biological materials as recorded over a seven-year period by the nursing staff in the hospital studied, and registered in the Network databank. The second stage involved the analysis of 122 nursing staff members' perception of the institutional culture, who were allocated to the control group (workers who had not had an accident) and the case group (workers who had had an accident). 386 accidents had been recorded: percutaneous lesions occurred in 79% of the cases, needles were the materials involved in 69.7% of the accidents, and in 81.9% of the accident there was contact with blood. Regarding the influence of the organizational culture on the occurrence of accidents, the results obtained through the analysis of the two groups did not demonstrate significant differences between the average scores attributed by the workers in each organizational value or practice category. It is concluded that accidents involving exposure to biological material need to be avoided, however, it was not possible to confirm the influence of organizational values or practices on workers' behavior concerning the occurrence of these accidents.

  19. Characterization and Modeling of Materials Responsible for Planetary Crustal Magnetism

    NASA Astrophysics Data System (ADS)

    Strauss, Becky E.

    Earth and Mercury are the only terrestrial planets in our solar system with present-day magnetic dipole fields generated by internal dynamo systems. In contrast, Mars and the Moon show evidence of past dipole fields in the form of crustal magnetic anomalies; to hold measurable magnetizations, crustal materials must have been exposed to an applied field. While the physical principles of magnetic recording are consistent between terrestrial planets, the particular conditions at each planet control the mechanisms by which crustal materials may be magnetized and limit the types of minerals that can retain magnetic remanence. As the suite of magnetic materials used for studies of remanence expands, the need for new methods follows. The integration of rock magnetic techniques with microscopy and chemical analyses enables the reconstruction of increasingly comprehensive narratives of remanence acquisition and alteration, even in materials that are challenging to study using traditional methods. This thesis demonstrates the utility of a materials approach to rock magnetism by applying techniques designed for terrestrial use in a planetary context. The first of two case studies focuses on calcite cave deposits as a means to demonstrate how novel techniques can be used to unlock previously inaccessible archives of magnetic information. Tandem magnetic and microscopic analyses improve our understanding of the rock magnetic properties of weakly magnetic stalagmites and their potential for paleomagnetic research, as well as illuminating the pathways of remanence acquisition in cave systems. The second case study addresses the magnetic anomalies recently detected by the MESSENGER orbiter at Mercury. These anomalies are consistent with remanence acquired in a dipole field. However, in the absence of physical samples, the types of magnetic minerals that could be holding remanence in Mercury's hot, highly reducing surface environment have not yet been determined. Orbital data is combined with fundamental rock magnetic principles to constrain the magnetic mineralogy of Mercury and to propose mechanisms of magnetization and remagnetization in the lithosphere.

  20. Doping as a means to probe the potential dependence of dopamine adsorption on carbon-based surfaces: A first-principles study

    NASA Astrophysics Data System (ADS)

    Aarva, Anja; Laurila, Tomi; Caro, Miguel A.

    2017-06-01

    In this work, we study the adsorption characteristics of dopamine (DA), ascorbic acid (AA), and dopaminequinone (DAox) on carbonaceous electrodes. Our goal is to obtain a better understanding of the adsorption behavior of these analytes in order to promote the development of new carbon-based electrode materials for sensitive and selective detection of dopamine in vivo. Here we employ density functional theory-based simulations to reach a level of detail that cannot be achieved experimentally. To get a broader understanding of carbonaceous surfaces with different morphological characteristics, we compare three materials: graphene, diamond, and amorphous carbon (a-C). Effects of solvation on adsorption characteristics are taken into account via a continuum solvent model. Potential changes that take place during electrochemical measurements, such as cyclic voltammetry, can also alter the adsorption behavior. In this study, we have utilized doping as an indirect method to simulate these changes by shifting the work function of the electrode material. We demonstrate that sp2- and sp3-rich materials, as well as a-C, respond markedly different to doping. Also the adsorption behavior of the molecules studied here differs depending on the surface material and the change in the surface potential. In all cases, adsorption is spontaneous, but covalent bonding is not detected in vacuum. The aqueous medium has a large effect on the adsorption behavior of DAox, which reaches its highest adsorption energy on diamond when the potential is shifted to more negative values. In all cases, inclusion of the solvent enhances the charge transfer between the slab and DAox. Largest differences in adsorption energy between DA and AA are obtained on graphene. Gaining better understanding of the behavior of the different forms of carbon when used as electrode materials provides a means to rationalize the observed complex phenomena taking place at the electrodes during electrochemical oxidation/reduction of these biomolecules.

  1. Fracture and Failure in Micro- and Nano-Scale

    NASA Astrophysics Data System (ADS)

    Charitidis, Costas A.

    Indentation and scratch in micro- and nano-scale are the most commonly used techniques for quantifying thin film and systems properties. Among them are different failure modes such as deformation, friction, fracture toughness, fatigue. Failure modes can be activated either by a cycle of indentation or by scratching of the samples to provide an estimation of the fracture toughness and interfacial fracture energies. In the present study, we report on the failure and fracture modes in two cases of engineering materials; that is transparent SiOx thin films onto poly(ethylene terephthalate) (PET) membranes and glass-ceramic materials. The SiOx/PET system meets the demands regarding scratch-resistance, wettability, biocompatibility, gas transmission, or friction, while maintaining the bulk characteristics of PET (such as easy processing, good mechanical properties, reasonably low permeability to oxygen and carbon dioxide gases (barrier properties), and good chemical coupling with antibacterial coatings). Glass-ceramic materials, since their first accidental production in the mid fifties by S.D. Stookey, have been used in a vast area of applications, from household cooktops and stoves, to missile nose cones and mirror mounts of orbital telescopes and from decorative wall coverings to medical applications. The fracture modes, namely transgranular and intergranular modes in glass-ceramic materials have paid less attention in literature comparing with ceramic materials. In the former case the crack paves its way irrespectively of the direction of the grain boundaries, i.e., the interfaces between the different phases. In the latter case the crack preferentially follows them, i.e., debonds the interfaces.

  2. Some Challenges for Raman Spectroscopy in Art History and the Preservation of Cultural Heritage

    NASA Astrophysics Data System (ADS)

    Edwards, H. G. M.

    2014-06-01

    Some challenges for the interpretation of Raman spectroscopic data derived from pigments and materials associated with oil paintings and cultural heritage artworks such as ivories are illustrated with several case studies.

  3. Geometry and mechanics of two-dimensional defects in amorphous materials

    PubMed Central

    Moshe, Michael; Levin, Ido; Aharoni, Hillel; Kupferman, Raz; Sharon, Eran

    2015-01-01

    We study the geometry of defects in amorphous materials and their elastic interactions. Defects are defined and characterized by deviations of the material’s intrinsic metric from a Euclidian metric. This characterization makes possible the identification of localized defects in amorphous materials, the formulation of a corresponding elastic problem, and its solution in various cases of physical interest. We present a multipole expansion that covers a large family of localized 2D defects. The dipole term, which represents a dislocation, is studied analytically and experimentally. Quadrupoles and higher multipoles correspond to fundamental strain-carrying entities. The interactions between those entities, as well as their interaction with external stress fields, are fundamental to the inelastic behavior of solids. We develop analytical tools to study those interactions. The model, methods, and results presented in this work are all relevant to the study of systems that involve a distribution of localized sources of strain. Examples are plasticity in amorphous materials and mechanical interactions between cells on a flexible substrate. PMID:26261331

  4. Seal Technology for Hypersonic Vehicle and Propulsion: An Overview

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.

    2008-01-01

    Hypersonic vehicles and propulsion systems pose an extraordinary challenge for structures and materials. Airframes and engines require lightweight, high-temperature materials and structural configurations that can withstand the extreme environment of hypersonic flight. Some of the challenges posed include very high temperatures, heating of the whole vehicle, steady-state and transient localized heating from shock waves, high aerodynamic loads, high fluctuating pressure loads, potential for severe flutter, vibration, and acoustic loads and erosion. Correspondingly high temperature seals are required to meet these aggressive requirements. This presentation reviews relevant seal technology for both heritage (e.g. Space Shuttle, X-15, and X-38) vehicles and presents several seal case studies aimed at providing lessons learned for future hypersonic vehicle seal development. This presentation also reviews seal technology developed for the National Aerospace Plane propulsion systems and presents several seal case studies aimed at providing lessons learned for future hypersonic propulsion seal development.

  5. Nursing distance education at the dawn of digital broadcasting: a case study in collaboration.

    PubMed

    Whitmore, Brent A

    2005-08-01

    For separate reasons, schools of nursing and public television stations are finding it a matter of mutual interest to work together in the production of distance education content for college nursing students in their communities. The advent of digital television (DTV) broadcasting has given these distance education partnerships new capabilities for reaching more potential students. In this article, I review one innovative collaboration between several nursing education programs and a public broadcasting service member station in South Texas. In this pilot project, nursing faculty were trained in television production techniques and became producers of DTV instructional video material. This case study demonstrates a number of ways in which nursing distance education programs can benefit by designing and delivering course material via digital broadcasting. It also highlights several difficulties that should be considered by distance educators prior to embarking on DTV curriculum development projects.

  6. The implications of starvation induced psychological changes for the ethical treatment of hunger strikers

    PubMed Central

    Fessler, D

    2003-01-01

    Design: Electronic databases were searched for (a) editorials and ethical proclamations on hunger strikers and their treatment; (b) studies of voluntary and involuntary starvation, and (c) legal cases pertaining to hunger striking. Additional studies were gathered in a snowball fashion from the published material cited in these databases. Material was included if it (a) provided ethical or legal guidelines; (b) shed light on psychological changes accompanying starvation, or (c) illustrated the practice of hunger striking. Authors' observations, opinions, and conclusions were noted. Conclusions: Although the heterogeneous nature of the sources precluded statistical analysis, starvation appears to be accompanied by marked psychological changes. Some changes clearly impair competence, in which case physicians are advised to follow advance directives obtained early in the hunger strike. More problematic are increases in impulsivity and aggressivity, changes which, while not impairing competence, enhance the likelihood that patients will starve themselves to death. PMID:12930863

  7. Terahertz Measurement of the Water Content Distribution in Wood Materials

    NASA Astrophysics Data System (ADS)

    Bensalem, M.; Sommier, A.; Mindeguia, J. C.; Batsale, J. C.; Pradere, C.

    2018-02-01

    Recently, THz waves have been shown to be an effective technique for investigating the water diffusion within porous media, such as biomaterial or insulation materials. This applicability is due to the sufficient resolution for such applications and the safe levels of radiation. This study aims to achieve contactless absolute water content measurements at a steady state case in semi-transparent solids (wood) using a transmittance THz wave range setup. First, a calibration method is developed to validate an analytical model based on the Beer-Lambert law, linking the absorption coefficient, the density of the solid, and its water content. Then, an estimation of the water content on a local scale in a transient-state case (drying) is performed. This study shows that THz waves are an effective contactless, safe, and low-cost technique for the measurement of water content in a porous medium, such as wood.

  8. The Use of Case Studies in an Undergraduate Biochemistry Course

    NASA Astrophysics Data System (ADS)

    Cornely, Kathleen

    1998-04-01

    Most college biochemistry courses are taught in a format in which the professor lectures and the student memorizes. Although this is the best method for conveying large amounts of material, it puts the student in the position of passive learner. The lecture-based format has not been abandoned, but has been supplemented with case study projects assigned to the students upon completion of the intermediary metabolism unit. The case study assignment is modeled on similar exercises carried out in medical school biochemistry courses in the US and around the world. A description of the assignment follows: a group of 4-5 students is given a case study which gives the medical history of a patient with an inherited metabolic disease. The group is asked to provide biochemical explanations for the patient's symptoms and to suggest an effective course of treatment. The evaluation consists of a short paper that the students write as a group. The assignment provides the opportunity for small group interaction within a larger class and emphasizes cooperative-collaborative learning. Students learn by researching the topic on their own and debating it in small group discussions, and in so doing, gain a sense of confidence in themselves and the material they have learned over the course of the semester. Solving a "real-life" problem helps develop analytical and higher-order thinking skills and allows the students to see how biochemical concepts they have learned apply to a clinical situation.

  9. "It's Not Their Job to Share Content": A Case Study of the Role of Senior Students in Adapting Teaching Materials as Open Educational Resources at the University of Cape Town

    ERIC Educational Resources Information Center

    Hodgkinson-Williams, Cheryl; Paskevicius, Michael

    2013-01-01

    Inspired by the Massachusetts Institute of Technology's landmark decision to make its teaching and learning materials freely available to the public as OpenCourseWare (OCW), many other higher education institutions have followed suit sharing resources now more generally referred to as Open Educational Resources (OER). The University of Cape Town…

  10. Coupling of order parameters, chirality, and interfacial structures in multiferroic materials.

    PubMed

    Conti, Sergio; Müller, Stefan; Poliakovsky, Arkady; Salje, Ekhard K H

    2011-04-13

    We study optimal interfacial structures in multiferroic materials with a biquadratic coupling between two order parameters. We discover a new duality relation between the strong coupling and the weak coupling regime for the case of isotropic gradient terms. We analyze the phase diagram depending on the coupling constant and anisotropy of the gradient term, and show that in a certain regime the secondary order parameter becomes activated only in the interfacial region.

  11. NARDAC (Naval Regional Data Automation Command) Operations: A Case Study.

    DTIC Science & Technology

    1984-09-01

    Long Beach, 1974 Sutmitted in partial fulfillment of the requirements for the degree of MASTER CF SCIENCI IN INFORMATION SYSTIES from the NAVAL...various pirts of the material Command. Therefore, it is appropriate to Zonsider centralizing the execution of these functions in NAVMAT. An...the Nance Committee recommended that the new ADP command be located under Chief of Naval Material (CNM) with a residual staff located under OP-094 to

  12. On the uniqueness of measuring elastoplastic properties from indentation: The indistinguishable mystical materials

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Ogasawara, Nagahisa; Zhao, Manhong; Chiba, Norimasa

    2007-08-01

    Indentation is widely used to extract material elastoplastic properties from the measured force-displacement curves. One of the most well-established indentation techniques utilizes dual (or plural) sharp indenters (which have different apex angles) to deduce key parameters such as the elastic modulus, yield stress, and work-hardening exponent for materials that obey the power-law constitutive relationship. However, the uniqueness of such analysis is not yet systematically studied or challenged. Here we show the existence of "mystical materials", which have distinct elastoplastic properties yet they yield almost identical indentation behaviors, even when the indenter angle is varied in a large range. These mystical materials are, therefore, indistinguishable by many existing indentation analyses unless extreme (and often impractical) indenter angles are used. Explicit procedures of deriving these mystical materials are established, and the general characteristics of the mystical materials are discussed. In many cases, for a given indenter angle range, a material would have infinite numbers of mystical siblings, and the existence maps of the mystical materials are also obtained. Furthermore, we propose two alternative techniques to effectively distinguish these mystical materials. The study in this paper addresses the important question of the uniqueness of indentation test, as well as providing useful guidelines to properly use the indentation technique to measure material elastoplastic properties.

  13. Application of NASTRAN to TFTR toroidal field coil structures

    NASA Technical Reports Server (NTRS)

    Chen, S. J.; Lee, E.

    1978-01-01

    The primary applied loads on the TF coils were electromagnetic and thermal. The complex structure and the tremendous applied loads necessitated computer type of solutions for the design problems. In the early stage of the TF coil design, many simplified finite element models were developed for the purpose of investigating the effects of material properties, supporting schemes, and coil case material on the stress levels in the case and in the copper coil. In the more sophisticated models that followed the parametric and scoping studies, the isoparametric elements, such as QUAD4, HEX8, and HEXA, were used. The analysis results from using these finite element models and the NASTRAN system were considered accurate enough to provide timely design information.

  14. Structure and properties of steel case-hardened by non-vacuum electron-beam cladding of carbon fibers

    NASA Astrophysics Data System (ADS)

    Losinskaya, A. A.; Lozhkina, E. A.; Bardin, A. I.

    2017-12-01

    At the present time, the actual problem of materials science is the increase in the steels performance characteristics. In the paper some mechanical properties of the case-hardened materials received by non-vacuum electron-beam cladding of carbon fibers are determined. The depth of the hardened layers varies from 1.5 to 3 mm. The impact strength of the samples exceeds 50 J/cm2. The wear resistance of the coatings obtained exceeds the properties of steel 20 after cementation and quenching with low tempering. The results of a study of the microhardness of the resulting layers and the microstructure are also given. The hardness of the surface layers exceeds 5700 MPa.

  15. Material flow analysis for an industry - A case study in packaging

    USGS Publications Warehouse

    Amey, E.B.; Sandgren, K.

    1996-01-01

    The basic materials used in packaging are glass, metals (primarily aluminum and steel), an ever-growing range of plastics, paper and paperboard, wood, textiles for bags, and miscellaneous other materials (such as glues, inks, and other supplies). They are fabricated into rigid, semi-rigid, or flexible containers. The most common forms of these containers include cans, drums, bottles, cartons, boxes, bags, pouches, and wraps. Packaging products are, for the most part, low cost, bulky products that are manufactured close to their customers. There is virtually no import or export of packaging products. A material flow analysis can be developed that looks at all inputs to an industrial sector, inventories the losses in processing, and tracks the fate of the material after its useful life. An example is presented that identifies the material inputs to the packaging industry, and addresses the ultimate fate of the materials used. ?? 1996 International Association for Mathematical Geology.

  16. Quantifying similarity of pore-geometry in nanoporous materials

    DOE PAGES

    Lee, Yongjin; Barthel, Senja D.; Dłotko, Paweł; ...

    2017-05-23

    In most applications of nanoporous materials the pore structure is as important as the chemical composition as a determinant of performance. For example, one can alter performance in applications like carbon capture or methane storage by orders of magnitude by only modifying the pore structure. For these applications it is therefore important to identify the optimal pore geometry and use this information to find similar materials. But, the mathematical language and tools to identify materials with similar pore structures, but different composition, has been lacking. We develop a pore recognition approach to quantify similarity of pore structures and classify themmore » using topological data analysis. This then allows us to identify materials with similar pore geometries, and to screen for materials that are similar to given top-performing structures. Using methane storage as a case study, we also show that materials can be divided into topologically distinct classes requiring different optimization strategies.« less

  17. Identification of Gifted African American Primary Grade Students through Leadership, Creativity, and Academic Performance in Curriculum Material Making and Peer-Teaching: A Case Study

    ERIC Educational Resources Information Center

    Zhbanova, Ksenia S.; Rule, Audrey C.; Stichter, Mary K.

    2015-01-01

    Research into identification of gifted early childhood students of minority groups through classroom activities is lacking. A focus in the United States on students with learning challenges and a lack of awareness of educators concerning the needs of early childhood gifted students are important causes of this situation. The current case study…

  18. Construction Material-Based Methodology for Military Contingency Base Construction: Case Study of Maiduguri, Nigeria

    DTIC Science & Technology

    2016-09-01

    NSDA Nigerian Steel Development Authority OPC ordinary Portland cement PDF population density factor RCC Reynolds Construction Company RHA rice...construction. Byproducts include blast furnace slag cement and gas. The increased use of steel scrap in production creates less dependence on the raw...The construction resources are gravel, cement , ready-mix concrete, lumber, steel , and brick. In some cases, there are multiple central areas in a

  19. Office of Workers’ Compensation Programs (OWCP). Data Codebook. Version 1.0

    DTIC Science & Technology

    1993-12-01

    Section 4. OWCP Data Codebook 4.1 Codebook Description ........................... 5 4.2 Codebook Column WHading Defnitions ............... 5 4.3 Data...OWCP (EARLY-REF) First character: variable. It was originally used T = Test group case between 1987 and 1990 in a C = Control group case study done...Nondestructive testing 4255 Fuel distribution system mechanic 3707 Metalizing 4301 Miscellaneous pliable materials work 3708 Metal process working 4351

  20. Battery resource assessment. Subtask 2.5: Battery manufacturing capability recycling of battery materials

    NASA Astrophysics Data System (ADS)

    Pemsler, P.

    1981-02-01

    Studies were conducted on the recycling of advanced battery system components for six different battery systems. These include: nickel/zinc, nickel/iron, zinc/chlorine, zinc/bromine, sodium/sulfur, and lithium-aluminum/iron sulfide. For each battery system, one or more processes were developed which would permit recycling of the major or active materials. Each recycle process was designed to produce a product material which can be used directly as a raw material by the battery manufacturer. Metal recoverabilities are in the range of 93 to 95% for all processes. In each case, capital and operating costs were developed for a recycling plant which processes 100,000 electric vehicle batteries per year.

  1. Paranuclear blue inclusions in metastatic undifferentiated small cell carcinoma in the bone marrow.

    PubMed

    Wittchow, R; Laszewski, M; Walker, W; Dick, F

    1992-09-01

    Paranuclear blue inclusions (PBIs) are frequently identified within metastatic undifferentiated small cell carcinoma (SCC) cells on air-dried bone marrow aspirates stained with Wright's stain. To determine the sensitivity and specificity of this finding, 116 bone marrow aspirates containing metastatic neoplasms were evaluated for the presence and frequency of PBIs. Bone marrow specimens included 47 cases of metastatic SCC of the lung, 13 cases of large cell lymphoma, 19 cases of neuroblastoma, five cases of small, noncleaved cell lymphoma, seven cases of rhabdomyosarcoma, three cases of Ewing's sarcoma, three cases of other sarcomas, and 19 cases of non-small cell carcinoma (adenocarcinoma). PBIs were identified in 40 of 47 (85%) cases of SCC and their frequency varied from 0 to 24% of tumor cells among different cases. In approximately half the cases of SCC, PBIs were identified in 1 to 4% tumor cells; and in eight cases, PBIs were present in 5% or more of tumor cells. PBIs were also identified in two of seven (29%) cases of rhabdomyosarcoma and one case of malignant peripheral nerve sheath tumor, but they were not seen in Ewing's sarcoma, small non-cleaved cell lymphoma, large cell lymphoma, neuroblastoma, or non-small cell carcinoma. In addition, PBIs were not seen in alcohol-fixed, Papanicolaou-stained cytology specimens containing SCC. Ultrastructurally, PBIs may represent phagocytized nuclear/cellular material. PBIs are a feature of small cell carcinoma on air-dried, cytologic material stained with Romanowsky type stains. Their presence may provide diagnostic information with regard to the differential diagnosis of metastatic SCC in the bone marrow. Future studies evaluating non-bone marrow Wright's stained fine-needle aspiration specimens are needed to determine if PBIs are useful in distinguishing SCC from other poorly differentiated tumors in the cytology laboratory.

  2. Material contrast does not predict earthquake rupture propagation direction

    USGS Publications Warehouse

    Harris, R.A.; Day, S.M.

    2005-01-01

    Earthquakes often occur on faults that juxtapose different rocks. The result is rupture behavior that differs from that of an earthquake occurring on a fault in a homogeneous material. Previous 2D numerical simulations have studied simple cases of earthquake rupture propagation where there is a material contrast across a fault and have come to two different conclusions: 1) earthquake rupture propagation direction can be predicted from the material contrast, and 2) earthquake rupture propagation direction cannot be predicted from the material contrast. In this paper we provide observational evidence from 70 years of earthquakes at Parkfield, CA, and new 3D numerical simulations. Both the observations and the numerical simulations demonstrate that earthquake rupture propagation direction is unlikely to be predictable on the basis of a material contrast. Copyright 2005 by the American Geophysical Union.

  3. Wrestling with Online Learning Technologies: Blind Students' Struggle to Achieve Academic Success

    ERIC Educational Resources Information Center

    Muwanguzi, Samuel; Lin, Lin

    2010-01-01

    This study examines the usability challenges and emotional reactions of blind college students in their attempts to access online educational materials and to communicate with colleagues through online technologies. A case study approach was adopted. Five students were interviewed regarding their online learning experiences using Blackboard, a…

  4. Analytical studies of the Space Shuttle orbiter nose-gear tire

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K.; Tanner, John A.; Peters, Jeanne M.; Robinson, Martha P.

    1991-01-01

    A computational procedure is presented for evaluating the analytic sensitivity derivatives of the tire response with respect to material and geometrical properties of the tire. The tire is modeled by using a two-dimensional laminated anisotropic shell theory with the effects of variation in material and geometric parameters included. The computational procedure is applied to the case of the Space Shuttle orbiter nose-gear tire subjected to uniform inflation pressure. Numerical results are presented which show the sensitivity of the different tire response quantities to variations in the material characteristics of both the cord and rubber.

  5. Evaluation of susceptibility of polymer and rubber materials intended into contact with drinking water on biofilm formation

    PubMed

    Szczotko, Maciej; Stankiewicz, Agnieszka; Jamsheer-Bratkowska, Małgorzata

    Plumbing materials in water distribution networks and indoor installations are constantly evolving. The application of new, more economical solutions with plastic materials eliminates the corrosion problems, however, do not fully protect the consumer against secondary microbial contamination of water intended for human consumption caused by the presence of a biofilm on the inner surface of materials applied. National Institute of Public Health - National Institute of Hygiene conducts research aimed at a comprehensive assessment of this type of materials, resulting their further marketing authorization in Poland. Evaluation and comparison of polymer and rubber materials intended to contact with water for the susceptibility to biofilm formation. Plastic materials (polyethylene, polypropylene, polyvinyl chloride) and rubber compounds (EPDM, NBR), from different manufacturers were evaluated. The study was carried out on 37 samples, which were divided into groups according to the material of which they were made. The testing was conducted according to the method based on conditions of dynamic flow of tap water. The level of bioluminescence in swabs taken from the surface of the tested materials was investigated with a luminometer. Evaluation of plastic materials does not show major objections in terms of hygienic assessment. All materials met the evaluation criteria established for methodology used. In case of rubber compounds, a substantial part clearly exceeded the limit values, which resulted in their negative assessment and elimination of these materials from domestic market. High susceptibility to the formation of biofilm in the group of products made of rubber compounds has been demonstrated. Examined plastic materials, except for several cases, do not revealed susceptibility to biofilm formation, but application of plastics for distribution of water intended for human consumption does not fully protect water from secondary, microbiological contamination. Complete verification of plumbing materials including biofilm formation test before their introduction into the domestic market should be continued.

  6. Feasibility and design study of a frictionless air mover for thermal management of electronics

    NASA Astrophysics Data System (ADS)

    Schacht, R.; Hausdorf, A.; Wunderle, B.

    2014-07-01

    A frictionless air mover concept is introduced in this paper. As opposed to a piezoelectric driven fan, the air mover is based on a flexible blade whose vibration is driven by means of a magnetic field. The blade is based on a polymer material. The paper presents the results of a feasibility analysis and an on-going comprehensive design study. The performance of the prototype amounted to 65% of a comparable piezoelectric fan. To enhance the performance, two different blade materials were investigated, as well as the influence of the coil shape and value. A further goal is to reduce the size and to investigate the influence of a casing. The design study resulted in a prototype of size of 50 × 14 × 35 mm2 including a casing. The performance could be doubled, to attain a volumetric flow rate of dot V ~14 l/min and a static pressure of ρstat = 3 Pa.

  7. The Promotion Strategy of Green Construction Materials: A Path Analysis Approach.

    PubMed

    Huang, Chung-Fah; Chen, Jung-Lu

    2015-10-14

    As one of the major materials used in construction, cement can be very resource-consuming and polluting to produce and use. Compared with traditional cement processing methods, dry-mix mortar is more environmentally friendly by reducing waste production or carbon emissions. Despite the continuous development and promotion of green construction materials, only a few of them are accepted or widely used in the market. In addition, the majority of existing research on green construction materials focuses more on their physical or chemical characteristics than on their promotion. Without effective promotion, their benefits cannot be fully appreciated and realized. Therefore, this study is conducted to explore the promotion of dry-mix mortars, one of the green materials. This study uses both qualitative and quantitative methods. First, through a case study, the potential of reducing carbon emission is verified. Then a path analysis is conducted to verify the validity and predictability of the samples based on the technology acceptance model (TAM) in this study. According to the findings of this research, to ensure better promotion results and wider application of dry-mix mortar, it is suggested that more systematic efforts be invested in promoting the usefulness and benefits of dry-mix mortar. The model developed in this study can provide helpful references for future research and promotion of other green materials.

  8. Multiscale analysis: a way to investigate laser damage precursors in materials for high power applications at nanosecond pulse duration

    NASA Astrophysics Data System (ADS)

    Natoli, J. Y.; Wagner, F.; Ciapponi, A.; Capoulade, J.; Gallais, L.; Commandré, M.

    2010-11-01

    The mechanism of laser induced damage in optical materials under high power nanosecond laser irradiation is commonly attributed to the presence of precursor centers. Depending on material and laser source, the precursors could have different origins. Some of them are clearly extrinsic, such as impurities or structural defects linked to the fabrication conditions. In most cases the center size ranging from sub-micrometer to nanometer scale does not permit an easy detection by optical techniques before irradiation. Most often, only a post mortem observation of optics permits to proof the local origin of breakdown. Multi-scale analyzes by changing irradiation beam size have been performed to investigate the density, size and nature of laser damage precursors. Destructive methods such as raster scan, laser damage probability plot and morphology studies permit to deduce the precursor densities. Another experimental way to get information on nature of precursors is to use non destructive methods such as photoluminescence and absorption measurements. The destructive and non destructive multiscale studies are also motivated for practical reasons. Indeed LIDT studies of large optics as those used in LMJ or NIF projects are commonly performed on small samples and with table top lasers whose characteristics change from one to another. In these conditions, it is necessary to know exactly the influence of the different experimental parameters and overall the spot size effect on the final data. In this paper, we present recent developments in multiscale characterization and results obtained on optical coatings (surface case) and KDP crystal (bulk case).

  9. Theoretical analysis of shock induced depolarization and current generation in ferroelectrics

    NASA Astrophysics Data System (ADS)

    Agrawal, Vinamra; Bhattacharya, Kaushik

    Ferroelectric generators are used to generate large magnitude current pulse by impacting a polarized ferroelectric material. The impact causes depolarization of the material and at high impact speeds, dielectric breakdown. Depending on the loading conditions and the electromechanical boundary conditions, the current or voltage profiles obtained vary. In this study, we explore the large deformation dynamic response of a ferroelectric material. Using the Maxwell's equations, conservation laws and the second law of thermodynamics, we derive the governing equations for the phase boundary propagation as well as the driving force acting on it. We allow for the phase boundary to contain surface charges which introduces the contribution of curvature of phase boundary in the governing equations and the driving force. This type of analysis accounts for the dielectric breakdown and resulting conduction in the material. Next, we implement the equations derived to solve a one dimensional impact problem on a ferroelectric material under different electrical boundary conditions. The constitutive law is chosen to be piecewise quadratic in polarization and quadratic in the strain. We solve for the current profile generated in short circuit case and for voltage profile in open circuited case. This work was made possible by the financial support of the US Air Force Office of Scientific Research through the Center of Excellence in High Rate Deformation Physics of Heterogeneous Materials (Grant: FA 9550-12-1-0091).

  10. 75 FR 15485 - Pipeline Safety: Workshop on Guidelines for Integrity Assessment of Cased Pipe

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-29

    ... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket ID...: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: Notice of workshop. SUMMARY... ``Guidelines for Integrity Assessment of Cased Pipe in Gas Transmission Pipelines'' and related Frequently...

  11. Housing Conditions Contribute to Underweight in Children: An Example From Rural Villages in Southeast Sulawesi, Indonesia.

    PubMed

    Tasnim, Tasnim; Dasvarma, Gouranga; Mwanri, Lillian

    2017-09-01

    The prevalence of underweight in children under 5 years of age is anomalously high in Konawe District, Southeast Sulawesi Province, Indonesia. This state of affairs may be related to poor housing conditions, such as limited access to clean water, the absence of a sanitary latrine, and the use of poor housing materials. Therefore, this study aimed to examine the effect of housing conditions on underweight in under-5 children in Konawe District. This study was conducted in 2013 in 5 health centres in Konawe District, Southeast Sulawesi Province, and used a case-control study design. The study recruited 400 under-5 children, including 100 of whom were cases and 300 of whom were age-matched controls (1:3). Cases were underweight children, while the controls were children with a normal nutritional status. The independent variables were the availability and types of water and latrine facilities and housing materials (roof, wall, and floor). The statistical analysis used Cox regression. A lack of water availability (odds ratio [OR], 5.0; 95% confidence interval [CI], 2.7 to 9.5; p<0.001), a lack of latrine availability in the home (OR, 2.5; 95% CI, 1.5 to 4.0; p<0.001), and poor-quality roofing materials (OR, 1.7; 95% CI, 1.1 to 2.7; p<0.02) significantly contributed to underweight in children. In contrast, the walls and the floors did not contribute to under-5 year children being underweight (p=0.09 and p=0.71, respectively). Sanitation facilities and roofing were identified as important factors to address in order to improve children's nutritional status. Children's health status was directly impacted by food intake via their nutritional status.

  12. Development and evaluation of elastomeric materials for geothermal applications

    NASA Technical Reports Server (NTRS)

    Mueller, W. A.; Kalfayan, S. H.; Reilly, W. W.; Ingham, J. D.

    1978-01-01

    A material for a casing packer for service for 24 hours in a geothermal environment was developed by synthesis of new elastomers and formulation of available materials. Formulation included use of commercial elastomer gumstocks and also crosslinking of plastic (high Tg) materials. Fibrous reinforcement of fluorocarbon rubbers was emphasized. Organic fiber reinforcement did not increase hot properties significantly. Glass fiber reinforcement gave significant increase in tensile properties. Elongation was reduced, and the glass-reinforced composition examined so far did not hold up well in the geothermal environment. Colloidal asbestos fibers were also investigated. A few experiments with polyphenyl ether gave material with low tensile and high compression set. Available high styrene SBR compositions were studied. Work to date suggests that new synthetic polymers will be required for service in geothermal environments.

  13. Radiological properties of plastics and TLD materials its application in radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Jabaseelan Samuel, E. James; Srinivasan, K.; Poopathi, V.

    2017-05-01

    In the current study, we evaluated the tissue equivalency of nine different commonly used thermoluminescence compounds and six plastic materials over the photon energy range of 15 KeV to 20 MeV. Our result confirmed that the ratio of number of electrons per gram, electron density of the entire TLD compounds and plastic materials to ICRU-44 soft tissue was lesser than unity, except in the case of polypropylene plastics. The effective atomic number ratio of all the plastic materials was also <1 excluding Poly-vinyl-chloride, and for TLD lithium borate material, it was <1 others which showed the deviation with respect to photon energy. Mass attenuation coefficient (µ/ϼ), mass absorption coefficient (µen/ρ) was calculated and the results are discussed in this paper.

  14. A systematic review of publications studies on medical tourism

    PubMed Central

    Masoud, Ferdosi; Alireza, Jabbari; Mahmoud, Keyvanara; Zahra, Agharahimi

    2013-01-01

    Introduction: Medical tourism for any study area is complex. Materials and Methods: Using full articles from other databases, Institute for Scientific Information (ISI), Science Direct, Emerald, Oxford, Magiran, and Scientific Information Database (SID), to examine systematically published articles about medical tourism in the interval 2000-2011 paid. Articles were obtained using descriptive statistics and content analysis categories were analyzed. Results: Among the 28 articles reviewed, 11 cases were a kind of research articles, three cases were case studies in Mexico, India, Hungary, Germany, and Iran, and 14 were case studies, review documents and data were passed. The main topics of study included the definition of medical tourism, medical tourists’ motivation and development of medical tourism, ethical issues in medical tourism, and impact on health and medical tourism marketing. Conclusion: The findings indicate the definition of medical tourism in various articles, and medical tourists are motivated. However, most studies indicate the benefits of medical tourism in developing countries and more developed countries reflect the consequences of medical tourism. PMID:24251287

  15. COMPREHENSIVE STANDARDS: THE POWER GENERATION CASE

    EPA Science Inventory

    This study presents an illustrative data base of material quantities and environmental effluents in the fuel cycles for alternative technologies of thermally generated power. The entire fuel cycle for each of the alternative ten technologies is outlined for a representative power...

  16. Nonsurgically retreated root filled teeth--radiographic findings after 20-27 years.

    PubMed

    Fristad, I; Molven, O; Halse, A

    2004-01-01

    To identify periapical changes in nonsurgically retreated root-filled teeth 20-27 years after root canal treatment. From an original material of 429 roots, retreated by undergraduate students in a teaching clinic, 112 roots in 70 individuals could be evaluated radiographically 20-27 years after treatment. The same roots had been studied 10-17 years earlier. The periapical condition was registered and compared by three observers in two series of intraoral radiographs taken 10-17 and 20-27 years after treatment. A retrospective analysis was performed to gain information about probable endodontic and nonendodontic reasons for extractions of lost roots, by evaluating their periapical status immediately after retreatment and at the 10-17-year follow-up. Favourable outcomes were observed in 11 roots that had radiolucencies at the 10-17-year follow-up. Eight of these roots had periapical pathosis preoperatively, five of them filled with surplus root filling material. The percentage of cases recorded as normal condition at the final follow-up was 95.5%, including five cases initially recorded with increased width of the apical periodontal space. Delayed healing as a result of surplus root filling material explained most of the cases with favourable outcome assessed many years after treatment. Twenty-eight roots were lost because of extraction during the observation period, 17 during the last 10 years. Based on status at previous follow-ups, endodontic failure seems to represent a minor reason for extraction in the material. Late periapical changes, with more successful cases, were recorded when a 10-17-year follow-up after root canal treatment was extended for another 10 years. Persistent asymptomatic periapical radiolucencies, especially those with overfill, should generally not be classified as failures, as many of them will heal after an extended observation period.

  17. Is it time to rebalance the case mix? A portfolio analysis of direct catheterization laboratory costs over a 5-year period.

    PubMed

    Plehn, Gunnar; Butz, Thomas; Maagh, Petra; Oernek, Ahmet; Meissner, Axel; Plehn, Natalie

    2016-11-03

    Cardiac catheterization laboratories (CLL) have continued to function as profit centers for hospitals. Due to a high percentage of material and labor costs, they are natural targets for process improvement. Our study applied a contribution margin (CBM) concept to evaluate costs and cost dynamics over a 5-year period. We retrospectively analyzed all procedures performed at a tertiary heart center between 2007 and 2011. Total variable costs, including labor time, material, and maintenance-expenses, were allocated at a global as well as a procedural level. CBM and CBM ratios were calculated by integration of individual DRG revenues. Annual case volume increased from 1288 to 1545. In parallel, overall profitability improved as indicated by a 2% increase in CBM ratio and a higher CBM generated per hour of CLL working time (4325 vs. 5892 €, p < 0.001). Coronary angiography generated higher average CBMs per hour than coronary or electrophysiological interventions (5831 vs. 3458 vs. 1495 €; p < 0.001). The latter are characterized by relatively high per case material expenditures. On a procedural level, DRG-specific trends as a steady improvement of examination time or an increase in material costs were detectable. The CBM concept allows a comprehensive analysis of CLL costs and cost dynamics. From a health service providers view, its range of application includes global profitability analysis, portfolio evaluation, and a detailed cost analysis of specific service lines. From a healthcare payers perspective, it may help to monitor hospital activities and to provide a solid data basis in cases where inappropriate developments are suspected. The calculation principle is simple which may increase user acceptance and thus the motivation of team members.

  18. Rational design of new electrolyte materials for electrochemical double layer capacitors

    NASA Astrophysics Data System (ADS)

    Schütter, Christoph; Husch, Tamara; Viswanathan, Venkatasubramanian; Passerini, Stefano; Balducci, Andrea; Korth, Martin

    2016-09-01

    The development of new electrolytes is a centerpiece of many strategies to improve electrochemical double layer capacitor (EDLC) devices. We present here a computational screening-based rational design approach to find new electrolyte materials. As an example application, the known chemical space of almost 70 million compounds is investigated in search of electrochemically more stable solvents. Cyano esters are identified as especially promising new compound class. Theoretical predictions are validated with subsequent experimental studies on a selected case. These studies show that based on theoretical predictions only, a previously untested, but very well performing compound class was identified. We thus find that our rational design strategy is indeed able to successfully identify completely new materials with substantially improved properties.

  19. Acid-base treated vermiculite as high performance adsorbent: Insights into the mechanism of cationic dyes adsorption, regeneration, recyclability and stability studies.

    PubMed

    Stawiński, Wojciech; Węgrzyn, Agnieszka; Dańko, Tomasz; Freitas, Olga; Figueiredo, Sónia; Chmielarz, Lucjan

    2017-04-01

    Additional treatment with NaOH of acid activated vermiculite results in even higher increase in the adsorption capacity in comparison to samples modified only in acidic solution (first step of activation) with respect to raw material. Optimization of treatment conditions and adsorption capacity for two cationic dyes (methylene blue (MB) and astrazon red (AR)), also as binary mixture, was evaluated. The capacity, based on column studies, increased from 48 ± 2 to 203 ± 4 mg g -1 in the case of methylene blue and from 51 ± 1 to 127 ± 2 mg g -1 in the case of astrazon red on starting and acid-base treated material, respectively. It was shown that adsorption mechanism changes for both cationic dyes after NaOH treatment and it results in decrease of adsorption rate. In binary mixtures methylene blue is bound stronger by adsorbent and astrazon red may be removed in initial stage of adsorption. Extensive studies on desorption/regeneration process proved high efficiency in recyclable use of all materials. Although cation exchange capacity decreases due to acid treatment, after base treatment exchange properties are used more efficiently. On the other hand, increased specific surface area has less significant contribution into the adsorption potential of studied materials. Obtained adsorbents worked efficiently in 7 adsorption-regeneration cycles and loss of adsorption capacity was observed only in two first cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Deformation and Life Analysis of Composite Flywheel Disk and Multi-disk Systems

    NASA Technical Reports Server (NTRS)

    Arnold, S. M.; Saleeb, A. F.; AlZoubi, N. R.

    2001-01-01

    In this study an attempt is made to put into perspective the problem of a rotating disk, be it a single disk or a number of concentric disks forming a unit. An analytical model capable of performing an elastic stress analysis for single/multiple, annular/solid, anisotropic/isotropic disk systems, subjected to both pressure surface tractions, body forces (in the form of temperature-changes and rotation fields) and interfacial misfits is derived and discussed. Results of an extensive parametric study are presented to clearly define the key design variables and their associated influence. In general the important parameters were identified as misfit, mean radius, thickness, material property and/or load gradation, and speed; all of which must be simultaneously optimized to achieve the "best" and most reliable design. Also, the important issue of defining proper performance/merit indices (based on the specific stored energy), in the presence of multiaxiality and material anisotropy is addressed. These merit indices are then utilized to discuss the difference between flywheels made from PMC and TMC materials with either an annular or solid geometry. Finally two major aspects of failure analysis, that is the static and cyclic limit (burst) speeds are addressed. In the case of static limit loads, upper, lower, and out-of-plane bounds for disks with constant thickness are presented for both the case of internal pressure loading (as one would see in a hydroburst test) and pure rotation (as in the case of a free spinning disk). The results (interaction diagrams) are displayed graphically in designer friendly format. For the case of fatigue, a representative fatigue/life master curve is illustrated in which the normalized limit speed versus number of applied cycles is given for a cladded TMC disk application.

  1. Proceedings of the Tri-Service Conference on Corrosion (1987) Held at the Air Force Academy, Colorado on 5-7 May 1987.

    DTIC Science & Technology

    1987-05-01

    j, ’er-,t- -- Case Studies of .- ’." Failures", Proceedinqs, 198O Tri-Ser vice Conference on Corrosion, AFWAL-TR-81- 401(, 1o1. 1, 2’.1-270, (II1). 3...Spiehler, 1981. Gulf of Mexico Study of "v’-. Biofouling on OTEC heat exchanger candidate alloys. Materials Performance 8:16-21. - Little, B. 1980... Case Studies Figure 2 shows the configuration of a straight shank attachment lug without bushing. All lugs, with or without bushing, that were

  2. A Homogenization Approach for Design and Simulation of Blast Resistant Composites

    NASA Astrophysics Data System (ADS)

    Sheyka, Michael

    Structural composites have been used in aerospace and structural engineering due to their high strength to weight ratio. Composite laminates have been successfully and extensively used in blast mitigation. This dissertation examines the use of the homogenization approach to design and simulate blast resistant composites. Three case studies are performed to examine the usefulness of different methods that may be used in designing and optimizing composite plates for blast resistance. The first case study utilizes a single degree of freedom system to simulate the blast and a reliability based approach. The first case study examines homogeneous plates and the optimal stacking sequence and plate thicknesses are determined. The second and third case studies use the homogenization method to calculate the properties of composite unit cell made of two different materials. The methods are integrated with dynamic simulation environments and advanced optimization algorithms. The second case study is 2-D and uses an implicit blast simulation, while the third case study is 3-D and simulates blast using the explicit blast method. Both case studies 2 and 3 rely on multi-objective genetic algorithms for the optimization process. Pareto optimal solutions are determined in case studies 2 and 3. Case study 3 is an integrative method for determining optimal stacking sequence, microstructure and plate thicknesses. The validity of the different methods such as homogenization, reliability, explicit blast modeling and multi-objective genetic algorithms are discussed. Possible extension of the methods to include strain rate effects and parallel computation is also examined.

  3. [Which one is more important, raw materials or productive technology?--a case study for quality consistency control of Gegen Qinlian decoction].

    PubMed

    Zhong, Wen; Chen, Sha; Zhang, Jun; Wang, Yu-Sheng; Liu, An

    2016-03-01

    To investigate the effect of Chinese medicine raw materials and production technology on quality consistency of Chinese patent medicines with Gegen Qinlian decoction as an example, and establish a suitable method for the quality consistency control of Chinese patent medicines. The results showed that the effect of production technology on the quality consistency was generally not more than 5%, while the effect of raw materials was even more than 30%, indicating that the effect of raw materials was much greater than that of the production technology. In this study, blend technology was used to improve the quality consistency of raw materials. As a result, the difference between the product produced by raw materials and reference groups was less than 5%, thus increasing the quality consistence of finished products. The results showed that under the current circumstances, the main factor affecting the quality consistency of Chinese patent medicines was raw materials, so we shall pay more attention to the quality of Chinese medicine's raw materials. Finally, a blend technology can improve the quality consistency of Chinese patent medicines. Copyright© by the Chinese Pharmaceutical Association.

  4. Exfoliative cytologic findings of primary pulmonary adenoid cystic carcinom: a report of 2 cases with a review of the cytologic features.

    PubMed

    Daneshbod, Yahya; Modjtahedi, Ebrahim; Atefi, Sohrab; Bedayat, Gholam Reza; Daneshbod, Khosrow

    2007-01-01

    Adenoid cystic carcinoma is a very rare primary pulmonary neoplasm. Cytologic findings of pulmonary washing and brushing in 2 cases of primary bronchial adenoid cystic carcinoma with special histologic features are described, with an emphasis on some points that have not been reported previously, together with the diagnostic pitfalls. Two cases of primary adenoid cystic carcinoma of the lung were diagnosed on exfoliative cytology. The patients' ages were 55 and 65 years old. Cytologic findings included large and small clusters of small cells in both 2 and 3 dimensions with occasional cystlike spaces containing mucoid material. The cells were arranged in spherical, cylindrical, basaloid and rosettelike arrangements. There were also abundant small and large mucoid globules, cylinders of homogeneous, acellular, mucous material and "cannon balls." Cytoplasmic and intranuclear round inclusions were noted in case 1. Rare findings of nuclear molding were noted. In case 2, chondromyxoid material and a bimorphic population of tumor cells caused diagnostic confusion with other salivary gland-type tumors of the lung. These cases showed characteristic cytologic findings of adenoid cystic carcinoma together with rare findings of intracellular and extracellular inclusionlike bodies, myxochondroid material, bimorphic populations and nuclear molding, which can cause diagnostic confusion with other lung tumors.

  5. In-situ subaqueous capping of mercury-contaminated sediments in a fresh-water aquatic system, Part II-evaluation of sorption materials.

    PubMed

    Randall, Paul M; Yates, Brian J; Lal, Vivek; Darlington, Ramona; Fimmen, Ryan

    2013-08-01

    The function and longevity of traditional, passive, isolation caps can be augmented through the use of more chemically active capping materials which have higher sorptive capacities, ideally rendering metals non-bioavailable. In the case of Hg, active caps also mitigate the rate and extent of methylation. This research examined low cost, readily available, capping materials for their ability to sequester Hg and MeHg. Furthermore, selected capping materials were evaluated to inhibit the methylation of Hg in an incubation study as well as the capacity of a selected capping material to inhibit translocation of Hg and MeHg with respect to ebullition-facilitated contaminant transport in a column study. Results indicated that bauxite had a better capacity for mercury sorption than the other test materials. However, bauxite as well as soil capping materials did not decrease methylation to a significant extent. Materials with larger surface areas, higher organic matter and acid volatile sulfide (AVS) content displayed a larger partitioning coefficient. In the incubation experiments, the presence of a carbon source (lactate), electron acceptor (sulfate) and the appropriate strains of SRB provided the necessary conditions for Hg methylation to occur. The column study showed effectiveness in sequestering Hg and MeHg and retarding transport to the overlying water column; however, disturbances to the soil capping material resulting from gas ebullition negated its effectiveness. Published by Elsevier Inc.

  6. The impact of using old germplasm on genetic merit and diversity-A cattle breed case study.

    PubMed

    Eynard, Sonia E; Windig, Jack J; Hulsegge, Ina; Hiemstra, Sipke-Joost; Calus, Mario P L

    2018-05-29

    Artificial selection and high genetic gains in livestock breeds led to a loss of genetic diversity. Current genetic diversity conservation actions focus on long-term maintenance of breeds under selection. Gene banks play a role in such actions by storing genetic materials for future use and the recent development of genomic information is facilitating characterization of gene bank material for better use. Using the Meuse-Rhine-Issel Dutch cattle breed as a case study, we inferred the potential role of germplasm of old individuals for genetic diversity conservation of the current population. First, we described the evolution of genetic merit and diversity over time and then we applied the optimal contribution (OC) strategy to select individuals for maximizing genetic diversity, or maximizing genetic merit while constraining loss of genetic diversity. In the past decades, genetic merit increased while genetic diversity decreased. Genetic merit and diversity were both higher in an OC scenario restricting the rate of inbreeding when old individuals were considered for selection, compared to considering only animals from the current population. Thus, our study shows that gene bank material, in the form of old individuals, has the potential to support long-term maintenance and selection of breeds. © 2018 The Authors. Journal of Animal Breeding and Genetics Published by Blackwell Verlag GmbH.

  7. Dental materials for cleft palate repair.

    PubMed

    Sharif, Faiza; Ur Rehman, Ihtesham; Muhammad, Nawshad; MacNeil, Sheila

    2016-04-01

    Numerous bone and soft tissue grafting techniques are followed to repair cleft of lip and palate (CLP) defects. In addition to the gold standard surgical interventions involving the use of autogenous grafts, various allogenic and xenogenic graft materials are available for bone regeneration. In an attempt to discover minimally invasive and cost effective treatments for cleft repair, an exceptional growth in synthetic biomedical graft materials have occurred. This study gives an overview of the use of dental materials to repair cleft of lip and palate (CLP). The eligibility criteria for this review were case studies, clinical trials and retrospective studies on the use of various types of dental materials in surgical repair of cleft palate defects. Any data available on the surgical interventions to repair alveolar or palatal cleft, with natural or synthetic graft materials was included in this review. Those datasets with long term clinical follow-up results were referred to as particularly relevant. The results provide encouraging evidence in favor of dental and other related biomedical materials to fill the gaps in clefts of lip and palate. The review presents the various bones and soft tissue replacement strategies currently used, tested or explored for the repair of cleft defects. There was little available data on the use of synthetic materials in cleft repair which was a limitation of this study. In conclusion although clinical trials on the use of synthetic materials are currently underway the uses of autologous implants are the preferred treatment methods to date. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Metal-Intermetallic Laminate Ti-Al3Ti Composites Produced by Spark Plasma Sintering of Titanium and Aluminum Foils Enclosed in Titanium Shells

    NASA Astrophysics Data System (ADS)

    Lazurenko, Daria V.; Mali, Vyacheslav I.; Bataev, Ivan A.; Thoemmes, Alexander; Bataev, Anatoly A.; Popelukh, Albert I.; Anisimov, Alexander G.; Belousova, Natalia S.

    2015-09-01

    Metal-intermetallic laminate composites are considered as promising materials for application in the aerospace industry. In this study, Ti-Al3Ti composites enclosed in titanium cases were produced by reactive spark plasma sintering. Sintering was carried out at 1103 K and 1323 K (830 °C and 1050 °C) for 10 minutes. In both cases, high-quality Ti-Al3Ti composites containing thin transition layers at the interfaces were obtained. Al2Ti, AlTi, and AlTi3 intermetallic phases and a solid solution of aluminum in titanium were observed in the transition layers by scanning and transmission electron microscopy. The material sintered at 1323 K (1050 °C) had higher strength in comparison with the composite obtained at 1103 K (830 °C). However, the hardness of the intermetallic component in the sample sintered at higher temperature decreased due to the grain growth. The impact toughness values of both materials were approximately identical.

  9. ToF-SIMS analysis of a polymer microarray composed of poly(meth)acrylates with C6 derivative pendant groups.

    PubMed

    Hook, Andrew L; Scurr, David J

    2016-04-01

    Surface analysis plays a key role in understanding the function of materials, particularly in biological environments. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) provides highly surface sensitive chemical information that can readily be acquired over large areas and has, thus, become an important surface analysis tool. However, the information-rich nature of ToF-SIMS complicates the interpretation and comparison of spectra, particularly in cases where multicomponent samples are being assessed. In this study, a method is presented to assess the chemical variance across 16 poly(meth)acrylates. Materials are selected to contain C 6 pendant groups, and ten replicates of each are printed as a polymer microarray. SIMS spectra are acquired for each material with the most intense and unique ions assessed for each material to identify the predominant and distinctive fragmentation pathways within the materials studied. Differentiating acrylate/methacrylate pairs is readily achieved using secondary ions derived from both the polymer backbone and pendant groups. Principal component analysis (PCA) is performed on the SIMS spectra of the 16 polymers, whereby the resulting principal components are able to distinguish phenyl from benzyl groups, mono-functional from multi-functional monomers and acrylates from methacrylates. The principal components are applied to copolymer series to assess the predictive capabilities of the PCA. Beyond being able to predict the copolymer ratio, in some cases, the SIMS analysis is able to provide insight into the molecular sequence of a copolymer. The insight gained in this study will be beneficial for developing structure-function relationships based upon ToF-SIMS data of polymer libraries. © 2016 The Authors Surface and Interface Analysis Published by John Wiley & Sons Ltd.

  10. The potential for fast van der Waals computations for layered materials using a Lifshitz model

    NASA Astrophysics Data System (ADS)

    Zhou, Yao; Pellouchoud, Lenson A.; Reed, Evan J.

    2017-06-01

    Computation of the van der Waals (vdW) interactions plays a crucial role in the study of layered materials. The adiabatic-connection fluctuation-dissipation theorem within random phase approximation (ACFDT-RPA) has been empirically reported to be the most accurate of commonly used methods, but it is limited to small systems due to its computational complexity. Without a computationally tractable vdW correction, fictitious strains are often introduced in the study of multilayer heterostructures, which, we find, can change the vdW binding energy by as much as 15%. In this work, we employed for the first time a defined Lifshitz model to provide the vdW potentials for a spectrum of layered materials orders of magnitude faster than the ACFDT-RPA for representative layered material structures. We find that a suitably defined Lifshitz model gives the correlation component of the binding energy to within 8-20% of the ACFDT-RPA calculations for a variety of layered heterostructures. Using this fast Lifshitz model, we studied the vdW binding properties of 210 three-layered heterostructures. Our results demonstrate that the three-body vdW effects are generally small (10% of the binding energy) in layered materials for most cases, and that non-negligible second-nearest neighbor layer interaction and three-body effects are observed for only those cases in which the middle layer is atomically thin (e.g. BN or graphene). We find that there is potential for particular combinations of stacked layers to exhibit repulsive three-body van der Waals effects, although these effects are likely to be much smaller than two-body effects.

  11. 17 CFR 240.10b5-1 - Trading “on the basis of” material nonpublic information in insider trading cases.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Trading âon the basis ofâ material nonpublic information in insider trading cases. 240.10b5-1 Section 240.10b5-1 Commodity and... Deceptive Devices and Contrivances § 240.10b5-1 Trading “on the basis of” material nonpublic information in...

  12. 17 CFR 240.10b5-1 - Trading “on the basis of” material nonpublic information in insider trading cases.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Trading âon the basis ofâ material nonpublic information in insider trading cases. 240.10b5-1 Section 240.10b5-1 Commodity and... Deceptive Devices and Contrivances § 240.10b5-1 Trading “on the basis of” material nonpublic information in...

  13. 17 CFR 240.10b5-1 - Trading “on the basis of” material nonpublic information in insider trading cases.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Trading âon the basis ofâ material nonpublic information in insider trading cases. 240.10b5-1 Section 240.10b5-1 Commodity and... Deceptive Devices and Contrivances § 240.10b5-1 Trading “on the basis of” material nonpublic information in...

  14. 17 CFR 240.10b5-1 - Trading “on the basis of” material nonpublic information in insider trading cases.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Trading âon the basis ofâ material nonpublic information in insider trading cases. 240.10b5-1 Section 240.10b5-1 Commodity and... Deceptive Devices and Contrivances § 240.10b5-1 Trading “on the basis of” material nonpublic information in...

  15. Report of NASA Lunar Energy Enterprise Case Study Task Force

    NASA Technical Reports Server (NTRS)

    Kearney, John J.

    1989-01-01

    The Lunar Energy Enterprise Case Study Task Force was asked to determine the economic viability and commercial potential of mining and extracting He-3 from the lunar soil, and transporting the material to Earth for use in a power-generating fusion reactor. Two other space energy projects, the Space Power Station (SPS) and the Lunar Power Station (LPS), were also reviewed because of several interrelated aspects of these projects. The specific findings of the Task Force are presented. Appendices contain related papers generated by individual Task Force Members.

  16. Writing about Clients: Ethical Considerations and Options

    ERIC Educational Resources Information Center

    Sperry, Len; Pies, Ronald

    2010-01-01

    Today, the decision to prepare clinical case material for publication is a decision that cannot be taken lightly. The decision involves reviewing ethical considerations and choosing among various options to safeguard client privacy. Such options include seeking the client's permission, disguising case material, and developing composite case…

  17. Teachers mathematical communication profile in explaining subject matter

    NASA Astrophysics Data System (ADS)

    Umami, Rohmatul; Budayasa, I. Ketut; Suwarsono, St.

    2017-12-01

    This study aimed to see a teachers mathematical communication profile in explaining a subject matter. It is a qualitative research. A high-school junior teacher (i.e., a teacher with 1- to 5-year experience) teaching mathematics at X-Social Class was selected as the subject of this study. The data was collected by observing the teachers mathematical communication in explaining a given material (i.e., the rule of sine) in class and an in-depth interview would be organized respectively. The result showed that the junior teacher explained the subject matter in systematic, complete, fluent, and centered manner. In this case, she began with reminding students on the previous material related to the current material to be learned, informing the current learning objectives, and finally delivering the subject matter. To support her explanation, the teacher also provided some related information, led the students attention into the given material by asking them particular related questions, and did not use any confusing terms. However, the study found that some of high-school teachers still used less appropriate language in explaining materials.

  18. Improving Self-Pierce Rivet Performance through Processing and Alloy Development

    NASA Astrophysics Data System (ADS)

    Van Hall, Stephen N.

    Spot welding has been used to join steel sheet material in the past during automotive manufacturing. The increasing use of aluminum and mixed materials to achieve continually increasing fuel economy standards requires mechanical joining methods to provide adequate impact performance. One such mechanical joining process is self-pierce riveting (SPR). Self-pierce riveting has grown in popularity in recent years due to fast cycle times, high static strength and fatigue performance as well as the ability to join many different sheet material combinations. Self-pierce rivet utilization has become limited due to the material properties of the rivet in two main areas: the joining of high-strength sheet material and joining of multiple sheet material combinations using a single rivet geometry, referred to as commonization. Two specific case studies have been developed to assess the failures that occur and evaluate potential solutions: joining of press-hardened steel (PHS) to Al6111 and improved commonization ability using a two layer aluminum joint that is currently joined with a specialized rivet. Riveting trials have been performed on each of the two case studies using cold forged rivets produced from 10B37 steel that has been heat-treated through a quench and temper process to a range of hardness levels to evaluate the failures that occur within the rivet. The failures occur with two different modes: buckling of the rivet at hardness values below 550 HV when joining PHS and Al6111 and fractures that occur in the rivet tail at hardness values above 550 HV during joining in each of the case studies under evaluation. The fractures have been attributed to a high degree of hoop strain that forms when the rivets are flared beyond the design specifications. A method to replicate the rivet flaring procedure under laboratory conditions has been developed by flaring the rivets through various strain paths to induce a hoop strain and the resultant fractures. The flaring method shows the ability to replicate the types of fractures that were observed during joining attempts while monitoring applied force, crosshead displacement and strain at the point of fracture at the rivet tail using digital image correlation. Alternative alloys including 4130, 4340 and 5160 were evaluated alongside 10B37 for improved performance after quenching and tempering, austempering and after being intentionally decarburized to varying degrees. The heat-treatments were evaluated through microscopy, fractography, rivet flaring and joining attempts for each case study and alloy under investigation. All of the alternative alloys showed no significant performance gains after being quenched and tempered or austempered. However, hoop strain to failure during flaring was increased between 2-4x after the rivets had been intentionally decarburized. The intentionally decarburized rivets were evaluated through joining trials and provided successful joining for each of the case studies under investigation using 10B37 rivets. Rivets produced from 4340 and 5160 also showed instances of success during joining attempts. The Cockroft and Latham failure criterion was evaluated in regards to rivet flaring through the development of finite element simulations using Abaqus. The Cockroft and Latham failure criterion was able to successfully predict the location of riveting fractures through multiple strain paths, rivet geometries and microstructures. Cockroft and Latham values from tensile tests of 10B37 wire led to an underestimate of the strain to failure when compared to the rivet flaring process for quenched and tempered rivets but was very similar to the strain predicted for rivets that had been intentionally decarburized.

  19. A Study to Improve the Brazilian Air Force’s Material Management System

    DTIC Science & Technology

    1991-12-01

    of Technology, in June 1990. Permanent Address: Base A6rea de Sio Paulo Instituto de Logistica da Aerongutica 07181 Guarulhos Sio Paulo Brazil 160 Vita...orders instead of more frequent smaller ones, and transportation from vendor to depot, which includes international fees in most cases, would be...optimized by the same reason. The transportation from depots to final users would not be affected, since only changes of depots and changes of material

  20. Variation, differential reproduction and oscillation: the evolution of nucleic acid hybridization.

    PubMed

    Suárez-Díaz, Edna

    2013-01-01

    This paper builds upon Hans-Jörg Rheinberger ideas on the oscillation and intercalation of epistemic things and technical objects in experimental systems, to give a fine-grained analysis of what here is called the problems of "adaptation" between our material and cognitive tools and the phenomena of the material world. To do so, it relies on the case-study of the evolution of nucleic acid hybridization and the stabilization of satellite DNA.

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