Framework for the Development of OER-Based Learning Materials in ODL Environment
ERIC Educational Resources Information Center
Teng, Khor Ean; Hung, Chung Sheng
2013-01-01
This paper describes the framework for the development of OER-based learning materials "TCC121/05 Programming Fundamentals with Java" for ODL learners in Wawasan Open University (WOU) using three main development phases mainly: creation, evaluation and production phases. The proposed framework has further been tested on ODL learners to…
Statistical research into low-power solar flares. Main phase duration
NASA Astrophysics Data System (ADS)
Borovik, Aleksandr; Zhdanov, Anton
2017-12-01
This paper is a sequel to earlier papers on time parameters of solar flares in the Hα line. Using data from the International Flare Patrol, an electronic database of solar flares for the period 1972-2010 has been created. The statistical analysis of the duration of the main phase has shown that it increases with increasing flare class and brightness. It has been found that the duration of the main phase depends on the type and features of development of solar flares. Flares with one brilliant point have the shortest main phase; flares with several intensity maxima and two-ribbon flares, the longest one. We have identified more than 3000 cases with an ultra-long duration of the main phase (more than 60 minutes). For 90% of such flares the duration of the main phase is 2-3 hrs, but sometimes it reaches 12 hrs.
Developing Open-Ended Questions for Surface Area and Volume of Beam
ERIC Educational Resources Information Center
Kurniawan, Henry; Putri, Ratu Ilma Indra; Hartono, Yusuf
2018-01-01
The purpose of this research was to show open-ended questions about surface area and beam volume which valid and practice, have potential effect. This research is research development which consists of two main phases: preliminary phase (preparation phase and problem design) and formative evaluation phase (evaluation and revision phases). The…
Synthesis and evaluation of phase detectors for active bit synchronizers
NASA Technical Reports Server (NTRS)
Mcbride, A. L.
1974-01-01
Self-synchronizing digital data communication systems usually use active or phase-locked loop (PLL) bit synchronizers. The three main elements of PLL synchronizers are the phase detector, loop filter, and the voltage controlled oscillator. Of these three elements, phase detector synthesis is the main source of difficulty, particularly when the received signals are demodulated square-wave signals. A phase detector synthesis technique is reviewed that provides a physically realizable design for bit synchronizer phase detectors. The development is based upon nonlinear recursive estimation methods. The phase detector portion of the algorithm is isolated and analyzed.
F layer positive response to a geomagnetic storm - June 1972
NASA Technical Reports Server (NTRS)
Miller, N. J.; Grebowsky, J. M.; Mayr, H. G.; Harris, I.; Tulunay, Y. K.
1979-01-01
A circulation model of neutral thermosphere-ionosphere coupling is used to interpret in situ spacecraft measurements taken during a topside midlatitude ionospheric storm. The data are measurements of electron density taken along the circular polar orbit of Ariel 4 at 550 km during the geomagnetically disturbed period June 17-18, 1972. It is inferred that collisional momentum transfer from the disturbed neutral thermosphere to the ionosphere was the dominant midday process generating the positive F-layer storm phase in the summer hemisphere. In the winter hemisphere the positive storm phase drifted poleward in the apparent response to magnetospheric E x B drifts. A summer F-layer positive phase developed at the sudden commencement and again during the geomagnetic main phase; a winter F-layer positive phase developed only during the geomagnetic main phase. The observed seasonal differences in both the onsets and the magnitudes of the positive phases are attributed to the interhemispheric asymmetry in thermospheric dynamics.
Ring magnet firing angle control
Knott, M.J.; Lewis, L.G.; Rabe, H.H.
1975-10-21
A device is provided for controlling the firing angles of thyratrons (rectifiers) in a ring magnet power supply. A phase lock loop develops a smooth ac signal of frequency equal to and in phase with the frequency of the voltage wave developed by the main generator of the power supply. A counter that counts from zero to a particular number each cycle of the main generator voltage wave is synchronized with the smooth AC signal of the phase lock loop. Gates compare the number in the counter with predetermined desired firing angles for each thyratron and with coincidence the proper thyratron is fired at the predetermined firing angle.
Space shuttle phase B study plan
NASA Technical Reports Server (NTRS)
Hello, B.
1971-01-01
Phase B emphasis was directed toward development of data which would facilitate selection of the booster concept, and main propulsion system for the orbiter. A shuttle system is also defined which will form the baseline for Phase C program activities.
History and Benefits of Engine Level Testing Throughout the Space Shuttle Main Engine Program
NASA Technical Reports Server (NTRS)
VanHooser, Katherine; Kan, Kenneth; Maddux, Lewis; Runkle, Everett
2010-01-01
Rocket engine testing is important throughout a program s life and is essential to the overall success of the program. Space Shuttle Main Engine (SSME) testing can be divided into three phases: development, certification, and operational. Development tests are conducted on the basic design and are used to develop safe start and shutdown transients and to demonstrate mainstage operation. This phase helps form the foundation of the program, demands navigation of a very steep learning curve, and yields results that shape the final engine design. Certification testing involves multiple engine samples and more aggressive test profiles that explore the boundaries of the engine to vehicle interface requirements. The hardware being tested may have evolved slightly from that in the development phase. Operational testing is conducted with mature hardware and includes acceptance testing of flight assets, resolving anomalies that occur in flight, continuing to expand the performance envelope, and implementing design upgrades. This paper will examine these phases of testing and their importance to the SSME program. Examples of tests conducted in each phase will also be presented.
Space Shuttle main engine product improvement
NASA Technical Reports Server (NTRS)
Lucci, A. D.; Klatt, F. P.
1985-01-01
The current design of the Space Shuttle Main Engine has passed 11 certification cycles, amassed approximately a quarter million seconds of engine test time in 1200 tests and successfully launched the Space Shuttle 17 times of 51 engine launches through May 1985. Building on this extensive background, two development programs are underway at Rocketdyne to improve the flow of hot gas through the powerhead and evaluate the changes to increase the performance margins in the engine. These two programs, called Phase II+ and Technology Test Bed Precursor program are described. Phase II+ develops a two-tube hot-gas manifold that improves the component environment. The Precursor program will evaluate a larger throat main combustion chamber, conduct combustion stability testing of a baffleless main injector, fabricate an experimental weld-free heat exchanger tube, fabricate and test a high pressure oxidizer turbopump with an improved inlet, and develop and test methods for reducing temperature transients at start and shutdown.
NASA Technical Reports Server (NTRS)
He, Zhuohui J.
2017-01-01
Two P&W (Pratt & Whitney)'s axially staged sector combustors have been developed under NASA's Environmentally Responsible Aviation (ERA) project. One combustor was developed under ERA Phase I, and the other was developed under ERA Phase II. Nitrogen oxides (NOx) emissions characteristics and correlation equations for these two sector combustors are reported in this article. The Phase I design was to optimize the NOx emissions reduction potential, while the Phase II design was more practical and robust. Multiple injection points and fuel staging strategies are used in the combustor design. Pilot-stage injectors are located on the front dome plate of the combustor, and main-stage injectors are positioned on the top and bottom (Phase I) or on the top only (Phase II) of the combustor liners downstream. Low power configuration uses only pilot-stage injectors. Main-stage injectors are added to high power configuration to help distribute fuel more evenly and achieve lean burn throughout the combustor yielding very low NOx emissions. The ICAO (International Civil Aviation Organization) landing-takeoff NOx emissions are verified to be 88 percent (Phase I) and 76 percent (Phase II) under the ICAO CAEP/6 (Committee on Aviation Environmental Protection 6th Meeting) standard, exceeding the ERA project goal of 75 percent reduction, and the combustors proved to have stable combustion with room to maneuver on fuel flow splits for operability.
Avery, Kerry N L; Williamson, Paula R; Gamble, Carrol; O'Connell Francischetto, Elaine; Metcalfe, Chris; Davidson, Peter; Williams, Hywel; Blazeby, Jane M
2017-02-17
Designing studies with an internal pilot phase may optimise the use of pilot work to inform more efficient randomised controlled trials (RCTs). Careful selection of preagreed decision or 'progression' criteria at the juncture between the internal pilot and main trial phases provides a valuable opportunity to evaluate the likely success of the main trial and optimise its design or, if necessary, to make the decision not to proceed with the main trial. Guidance on the appropriate selection and application of progression criteria is, however, lacking. This paper outlines the key issues to consider in the optimal development and review of operational progression criteria for RCTs with an internal pilot phase. A structured literature review and exploration of stakeholders' opinions at a Medical Research Council (MRC) Hubs for Trials Methodology Research workshop. Key stakeholders included triallists, methodologists, statisticians and funders. There is considerable variation in the use of progression criteria for RCTs with an internal pilot phase, although 3 common issues predominate: trial recruitment, protocol adherence and outcome data. Detailed and systematic reporting around the decision-making process for stopping, amending or proceeding to a main trial is uncommon, which may hamper understanding in the research community about the appropriate and optimal use of RCTs with an internal pilot phase. 10 top tips for the development, use and reporting of progression criteria for internal pilot studies are presented. Systematic and transparent reporting of the design, results and evaluation of internal pilot trials in the literature should be encouraged in order to facilitate understanding in the research community and to inform future trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Williamson, Paula R; Gamble, Carrol; O'Connell Francischetto, Elaine; Metcalfe, Chris; Davidson, Peter; Williams, Hywel; Blazeby, Jane M
2017-01-01
Objectives Designing studies with an internal pilot phase may optimise the use of pilot work to inform more efficient randomised controlled trials (RCTs). Careful selection of preagreed decision or ‘progression’ criteria at the juncture between the internal pilot and main trial phases provides a valuable opportunity to evaluate the likely success of the main trial and optimise its design or, if necessary, to make the decision not to proceed with the main trial. Guidance on the appropriate selection and application of progression criteria is, however, lacking. This paper outlines the key issues to consider in the optimal development and review of operational progression criteria for RCTs with an internal pilot phase. Design A structured literature review and exploration of stakeholders' opinions at a Medical Research Council (MRC) Hubs for Trials Methodology Research workshop. Key stakeholders included triallists, methodologists, statisticians and funders. Results There is considerable variation in the use of progression criteria for RCTs with an internal pilot phase, although 3 common issues predominate: trial recruitment, protocol adherence and outcome data. Detailed and systematic reporting around the decision-making process for stopping, amending or proceeding to a main trial is uncommon, which may hamper understanding in the research community about the appropriate and optimal use of RCTs with an internal pilot phase. 10 top tips for the development, use and reporting of progression criteria for internal pilot studies are presented. Conclusions Systematic and transparent reporting of the design, results and evaluation of internal pilot trials in the literature should be encouraged in order to facilitate understanding in the research community and to inform future trials. PMID:28213598
Critical phases in the seed development of common juniper (Juniperus communis).
Gruwez, R; Leroux, O; De Frenne, P; Tack, W; Viane, R; Verheyen, K
2013-01-01
Common juniper (Juniperus communis L.) populations in northwest European lowlands are currently declining in size and number. An important cause of this decline is a lack of natural regeneration. Low seed viability seems to be one of the main bottlenecks in this process. Previous research revealed a negative relation between seed viability and both temperature and nitrogen deposition. Additionally, the seeds of common juniper have a variable ripening time, which possibly influences seed viability. However, the underlying mechanisms remain unresolved. In order to elucidate this puzzle, it is important to understand in which phases of seed production the main defects are situated, together with the influence of ripening time. In this study, we compared seed viability of populations with and without successful recruitment. We examined three seed phases: (i) gamete development; (ii) fertilisation and early-embryo development; and (iii) late-embryo development. After the first two phases, we found no difference in the percentage viable seeds between populations with or without recruitment. After late-embryo development, populations without recruitment showed a significantly lower percentage of viable seeds. These results suggest that late-embryo development is a bottleneck in seed development. However, the complex interaction between seed viability and ripening time suggest that the causes should be in the second seed phase, as the accelerated development of male and female gametophytes may disturb the male-female synchrony for successful mating. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.
Junior High School Science: A Manual for Teachers. A Search for Structure. Grade 7.
ERIC Educational Resources Information Center
Baltimore County Public Schools, Towson, MD.
GRADES OR AGES: Grade 7. SUBJECT MATTER: Science. ORGANIZATION AND PHYSICAL APPEARANCE: The introduction describes the development of the junior high school science program. The main text is divided into three phases: Processes and Skills, Developing a Model of Matter, and Human Structure and Function. Phase I contains two subcategories: Rocks and…
Nano-particle modified stationary phases for high-performance liquid chromatography.
Nesterenko, Ekaterina P; Nesterenko, Pavel N; Connolly, Damian; He, Xiaoyun; Floris, Patrick; Duffy, Emer; Paull, Brett
2013-08-07
This review covers the latest developments and applications of nano-materials in stationary phase development for various modes of high-performance liquid chromatography. Specific attention is placed upon the development of new composite phases, including the synthetic and immobilisation strategies used, to produce either encapsulated nano-particles, or surface attached nano-particles, layers, coatings and other structures. The resultant chromatographic applications, where applicable, are discussed with comment upon enhanced selectivity and/or efficiency of the nano-particle modified phases, where such effects have been identified. In the main this review covers developments over the past five years and is structured according to the nature of the nano-particles themselves, including carbonaceous, metallic, inorganic, and organopolymer based materials.
Lightweight Phase-Change Material For Solar Power
NASA Technical Reports Server (NTRS)
Stark, Philip
1993-01-01
Lightweight panels containing phase-change materials developed for use as heat-storage elements of compact, lightweight, advanced solar dynamic power system. During high insolation, heat stored in panels via latent heat of fusion of phase-change material; during low insolation, heat withdrawn from panels. Storage elements consist mainly of porous carbon-fiber structures imbued with germanium. Developed for use aboard space station in orbit around Earth, also adapted to lightweight, compact, portable solar-power systems for use on Earth.
Smart sign enhancement : executive summary report.
DOT National Transportation Integrated Search
2007-09-01
In the Smart Sign Ordering System (Phase I) the : University of Akron developed an on-line : interactive traffic-sign ordering system for ODOT. : The main focus of SSOS Phase I was to provide : ODOT with a fully automated and networked sign : orderin...
This paper highlights the development of the emission inventories and emission processing for Europe (EU) and North America (NA) in the second phase of the Air Quality Model Evaluation International Initiative (AQMEII) project. The main purpose of the second phase of the AQMEII...
Magnetic sensor for nondestructive evaluation of deteriorated prestressing strand : phase II.
DOT National Transportation Integrated Search
2011-08-01
This report gives an account of the execution and achievements in Phase II of the project completed through August 2011. The main objective of this project is to advance the practical development of a nondestructive testing and evaluation method usin...
Regional and contact metamorphism within the Moy Intrusive Complex, Grampian Highlands, Scotland
NASA Astrophysics Data System (ADS)
Zaleski, E.
1985-04-01
In central Scotland, the Moy Intrusive Complex consists of (1) the Main Phase — syntectonic peraluminous granodiorite to granite emplaced at c. 455 Ma, intruded by (2) the Finglack Alaskite — post-tectonic leucocratic granite emplaced at 407+/-5 Ma. The Main Phase was emplaced into country rocks at amphibolite facies temperatures. Rb-Sr dates and a compositional spectrum of decreasing celadonite content in Main Phase muscovite suggest the persistence of c. 550° C temperatures for c. 30 Ma but with a declining pressure regime, i.e. isothermal uplift. The Finglack Alaskite was intruded at high structural level, leading to the development of a contact metamorphic aureole in the Main Phase. The thermal effects of contact metamorphism include intergrowths of andalusite, biotite and feldspar in pseudomorphs after muscovite. This is associated with recrystallized granoblastic quartz. Muscovite breakdown and reaction with adjacent biotite, quartz and feldspar, i.e. a function of local mineral assemblage rather than bulk rock composition, is postulated to explain the occurrence of metamorphic andalusite in a granitoid rock. The Main Phase pluton of the Moy Intrusive Complex lies within a NNE trending belt of c. 450 Ma Caledonian tectonic and magmatic activity paralleling the Moine Thrust, and extending from northern Scotland to the Highland Boundary Fault. Syntectonic ‘S-type’ magmatism with upper crustal source areas implies crustal thickening and suggests an intracratonic orogeny.
Offshore wind development research (technical brief).
DOT National Transportation Integrated Search
2014-04-01
The study addresses all aspects of Offshore Wind (OSW) development. This includes identifying : vessel types, vessel installation methods, needs and operating characteristics through all phases : of OSW installation, construction, operations and main...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-15
... study design elements for a prospective, national longitudinal study of child health and development. In combination, the substudies encompassed by the Vanguard phase will be used to inform the design of the Main... that are to be used in the design of the NCS Main Study. The Vanguard Study begins prior to the NCS...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-26
... purpose of the proposed methodological study is to continue the Vanguard phase of the National Children's... health and development. In combination, these studies will be used to inform the design of the Main Study... and to inform the design of the Main Study. Methods Provider Based Sampling We will compile a list of...
den Breejen, Elvira M E; Hermens, Rosella P M G; Galama, Wienke H; Willemsen, Wim N P; Kremer, Jan A M; Nelen, Willianne L D M
2016-06-01
Patient involvement in scoping the guideline is emphasized, but published initiatives actively involving patients are generally limited to the writing and reviewing phase. To assess patients' added value to the scoping phase of a multidisciplinary guideline on infertility. Qualitative interview study. We conducted interviews among 12 infertile couples and 17 professionals. We listed and compared the couples' and professionals' key clinical issues (=care aspects that need improvement) to be addressed in the guideline according to four domains: current guidelines, professionals, patients and organization of care. Main key clinical issues suggested by more than three quarters of the infertile couples and/or at least two professionals were identified and compared. Overall, we identified 32 key clinical issues among infertile couples and 23 among professionals. Of the defined main key clinical issues, infertile couples mentioned eight issues that were not mentioned by the professionals. These main key clinical issues mainly concerned patient-centred (e.g. poor information provision and poor alignment of care) aspects of care on the professional and organizational domain. Both groups mentioned two main key clinical issues collectively that were interpreted differently: the lack of emotional support and respect for patients' values. Including patients from the first phase of the guideline development process leads to valuable additional main key clinical issues for the next step of a multidisciplinary guideline development process and broadens the scope of the guideline, particularly regarding patient-centredness and organizational issues from a patients' perspective. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care; all rights reserved.
Time-resolved imaging of the plasma development in a triggered vacuum switch
NASA Astrophysics Data System (ADS)
Park, Wung-Hoa; Kim, Moo-Sang; Son, Yoon-Kyoo; Frank, Klaus; Lee, Byung-Joon; Ackerman, Thilo; Iberler, Marcus
2017-12-01
Triggered vacuum switches (TVS) are particularly used in pulsed power technology as closing switches for high voltages and high charge transfer. A non-sealed-off prototype was designed with a side-on quartz window to investigate the evolution of the trigger discharge into the main discharge. The image acquisition was done with a fast CCD camera PI-MAX2 from Princeton Instruments. The CCD camera has a maximum exposure time of 2 ns. The electrode configuration of the prototype is a conventional six-rod gap type, a capacitor bank with C = 16.63 μF, which corresponds at 20 kV charging voltage to a total stored charge of 0.3 C or a total energy of 3.3 kJ. The peak current is 88 kA. According to the tremendously highly different light intensities during the trigger and main discharge, the complete discharge is split into three phases: a trigger breakdown phase, an intermediate phase and a main discharge phase. The CCD camera images of the first phase show instabilities of the trigger breakdown, in phase 2 three different discharge modes are observed. After the first current maximum the discharge behavior is reproducible.
DOT National Transportation Integrated Search
2014-01-01
The Maine Department of Transportation (MaineDOT) has noted poor correlation between predicted pile resistances : calculated using commonly accepted design methods and measured pile resistance from dynamic pile load tests (also : referred to as high ...
DOT National Transportation Integrated Search
2014-01-01
The Maine Department of Transportation (MaineDOT) has noted poor correlation between predicted pile resistances : calculated using commonly accepted design methods and measured pile resistance from dynamic pile load tests (also : referred to as high ...
Ring Current Development During Storm Main Phase
NASA Technical Reports Server (NTRS)
Fok, Mei-Ching; Moore, Thomas E.; Greenspan, Marian E.
1996-01-01
The development of the ring current ions in the inner magnetosphere during the main phase of a magnetic storm is studied. The temporal and spatial evolution of the ion phase space densities in a dipole field are calculated using a three dimensional ring current model, considering charge exchange and Coulomb losses along drift paths. The simulation starts with a quiet time distribution. The model is tested by comparing calculated ion fluxes with Active Magnetospheric Particle Tracer Explorers/CCE measurement during the storm main phase on May 2, 1986. Most of the calculated omnidirectional fluxes are in good agreement with the data except on the dayside inner edge (L less than 2.5) of the ring current, where the ion fluxes are underestimated. The model also reproduces the measured pitch angle distributions of ions with energies below 10 keV. At higher energy, an additional diffusion in pitch angle is necessary in order to fit the data. The role of the induced electric field on the ring current dynamics is also examined by simulating a series of substorm activities represented by stretching and collapsing the magnetic field lines. In response to the impulsively changing fields, the calculated ion energy content fluctuates about a mean value that grows steadily with the enhanced quiescent field.
NASA Astrophysics Data System (ADS)
Deschamps, A.; de Geuser, F.; Decreus, B.; Malard, B.
Al-Cu-Li based alloys are experiencing a rapid development for aerospace applications. The main hardening phase of this system (T1-Al2CuLi) forms as thin platelets (1 nm) that can reach diameters of 50 to 100 nm with remarkable stability in temperature. The nucleation, growth and thickening mechanisms of this phase are of crucial importance for the understanding of the microstructures resulting from simple to complex thermo-mechanical treatments, including friction stir welding of such alloys.
Learn by Doing - Phase I of the ToxCast Research Program
In 2007, the USEPA embarked on a multi-year, multi-million dollar research program to develop and evaluate a new approach to prioritizing the toxicity testing of environmental chemicals. ToxCast was divided into three main phases of effort – a proof of concept, an expansion and ...
NASA Technical Reports Server (NTRS)
Shelley, E. G.; Klumpar, D. M.; Peterson, W. K.; Ghielmetti, A.; Balsiger, H.; Geiss, J.; Rosenbauer, H.
1985-01-01
Observations from the Hot Plasma Composition Experiment on the AMPTE/CCE spacecraft during the magnetic storm of 4-5 September 1984 reveal that significant injection of ions of terrestrial origin accompanied the storm development. The compression of the magnetosphere at storm sudden commencement carried the magnetopause inside the CCE orbit clearly revealing the shocked solar wind plasma. A build up of suprathermal ions is observed near the plasmapause during the storm main phase and recovery phase. Pitch angle distributions in the ring current during the main phase show differences between H(+) and O(+) that suggest mass dependent injection, transport and/or loss processes.
Nonlinear evolution of energetic-particles-driven waves in collisionless plasmas
NASA Astrophysics Data System (ADS)
Li, Shuhan; Liu, Jinyuan; Wang, Feng; Shen, Wei; Li, Dong
2018-06-01
A one-dimensional electrostatic collisionless particle-in-cell code has been developed to study the nonlinear interaction between electrostatic waves and energetic particles (EPs). For a single wave, the results are clear and agree well with the existing theories. For coexisting two waves, although the mode nonlinear coupling between two wave fields is ignored, the second-order phase space islands can still exist between first-order islands generated by the two waves. However, the second-order phase islands are not formed by the superposed wave fields and the perturbed motions of EPs induced by the combined effect of two main resonances make these structures in phase space. Owing to these second-order islands, energy can be transferred between waves, even if the overlap of two main resonances never occurs. Depending on the distance between the main resonance islands in velocity space, the second-order island can affect the nonlinear dynamics and saturations of waves.
Choi, Yun Jeong; Lim, Ji Young; Lee, Young Whee; Kim, Hwa Soon
2008-10-01
The purpose of this study was to develop visions of nursing service, nursing strategies and key performance indicators (KPIs) for an intensive care unit (ICU) based on a Balanced Scorecard (BSC). This study was undertaken by using methodological research. The development process consisted of four phases; the first phase was to develop the vision of nursing in ICUs. The second phase was to develop strategies according to 4 perspectives of a BSC. The third phase was to develop KPIs according to the 4 perspectives of BSC and the final phase was to combine the nursing visions, strategies and KPIs of ICUs. Two main visions of nursing service for ICUs were established. These were 'realization of harmonized professional nursing with human respect' and 'recovery of health through specialized nursing' respectively. In order to reach the aim of developing nursing visions, thirteen practical strategies and nineteen KPIs were developed by four perspectives of the BSC. The results will be used as objective fundamental data to attain business outcomes for the achievement of nursing visions and strategies of ICUs.
Furukawa, Makoto; Takagai, Yoshitaka
2016-10-04
Online solid-phase extraction (SPE) coupled with inductively coupled plasma mass spectrometry (ICPMS) is a useful tool in automatic sequential analysis. However, it cannot simultaneously quantify the analytical targets and their recovery percentages (R%) in one-shot samples. We propose a system that simultaneously acquires both data in a single sample injection. The main flowline of the online solid-phase extraction is divided into main and split flows. The split flow line (i.e., bypass line), which circumvents the SPE column, was placed on the main flow line. Under program-controlled switching of the automatic valve, the ICPMS sequentially measures the targets in a sample before and after column preconcentration and determines the target concentrations and the R% on the SPE column. This paper describes the system development and two demonstrations to exhibit the analytical significance, i.e., the ultratrace amounts of radioactive strontium ( 90 Sr) using commercial Sr-trap resin and multielement adsorbability on the SPE column. This system is applicable to other flow analyses and detectors in online solid phase extraction.
Investigation on the mode of AC discharge in H2O affected by temperature
NASA Astrophysics Data System (ADS)
Siyuan, DONG; Shaomeng, GUO; Dan, WEN; Xiaoliang, TANG; Gao, QIU
2018-04-01
In this paper, some experimental equipment has been set up for kHz frequency AC liquid phase discharge, and the temperature of the deionized water was regulated during discharge. The electrical characteristics and spectra of liquid phase H2O discharge have been investigated. Two discharge modes, high temperature and low temperature, were both found. The results show that there are two mechanisms in liquid phase discharge: the field ionization mechanism and the breakdown mechanism of bubbles, and these two mechanisms are always developed simultaneously; the temperature is the key factor determining the discharge type. At high temperature, the breakdown of bubbles is the main discharge mechanism, and the field ionization mechanism occurs mainly at low temperature.
Lower Colorado River Proposed General Permit Main Report and Final Environmental Impact Statement.
1982-04-01
developed in two phases. Phase I consisted of the compilation of a data base establishing pertinent environmental parameters and inventorying resources...The result of Phase 1 investigations was a document entitled "Preliminary Enviornmental Resources Inventory Report (PERIR), Vols. I and II", dated...upstream just belo-1arker Dam, and river access is limited. Further, fewer pleasure boaters and water skiers are present. For these reasons, fishing is more
NASA Astrophysics Data System (ADS)
Shprits, Y.; Chen, Y.; Friedel, R.; Kondrashov, D.; Ni, B.; Subbotin, D.; Reeves, G.; Ghil, M.
2009-04-01
We present first results of the UCLA-LANL Reanalysis Project. Radiation belt relativistic electron Phase Space Density is obtained using the data assimilative VERB code combined with observations from GEO, CRRES, and Akebono data. Reanalysis of data shows the pronounced peaks in the phase space density and pronounced dropouts of fluxes during the main phase of a storm. The results of the reanalysis are discussed and compared to the simulations with the recently developed VERB 3D code.
USDA-ARS?s Scientific Manuscript database
Shiga toxins (Stxs) produced by Shiga toxin-producing Escherichia coli (STEC) are considered as the main causative agent, leading to the development of the hemolytic uremic syndrome (HUS); these toxins injure endothelial cells mainly the glomeruli. After passing through the intestinal wall, Stxs hav...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-04
...: The purpose of the proposed methodological study is to continue the Vanguard phase of the National... study design elements for a prospective, national longitudinal study of child health and development. In combination, the sub-studies encompassed by the Vanguard Phase will be used to inform the design of the Main...
Attitude towards Azeri Language in Iran: A Large-Scale Survey Research
ERIC Educational Resources Information Center
Rezaei, Saeed; Latifi, Ashkan; Nematzadeh, Arash
2017-01-01
This survey research investigated the attitude of Iranian Azeri native speakers towards Azeri language. A questionnaire was developed and its reliability was estimated (r = 0.74) through a piloting phase on 54 Azeri native speakers. The participants, for the main phase of this study, were 400 Azeri native speakers with different social and…
ERIC Educational Resources Information Center
New Educational Directions, Crawfordsville, IN.
Phase 2 of this project presents a skeletal model for evaluating vocational education programs which can be applied to secondary, post-secondary, and adult education programs. The model addresses 13 main components of the vocational education system: descriptive information, demonstration of need, student recruitment and selection, curriculum,…
Polymorphism and disorder in caffeine: Dielectric investigation of molecular mobilities
NASA Astrophysics Data System (ADS)
Descamps, M.; Decroix, A. A.
2014-12-01
Using dielectric relaxation data we have characterized the molecular mobilities of caffeine both in phase I (stable and metastable) and in phase II. In phase I effects of sublimation and phase transformation kinetics were carefully considered. In plane rotational motions were followed on a wide temperature range. A noticeable antiferroelectric short range order developing at the approach of the glass-like transition is characterized. Condition for occurrence of a critical-like behaviour is discussed. At high temperature the emergence of an additional ultra slow relaxation process is highlighted. Possible molecular mechanisms are proposed for both processes. In phase II the existence of a less intense relaxation process is confirmed. Close similarity with the main process developing in phase I hints at a common origin of the dipolar motions. Careful consideration of recent structure determinations leads to suggest that this process is associated to similar molecular in plane rotations but developing at the surface of crystalline samples. Lower cooperativity at the surface is reflected in the smaller activation entropy of the relaxation.
Integrated Design Methodology for Highly Reliable Liquid Rocket Engine
NASA Astrophysics Data System (ADS)
Kuratani, Naoshi; Aoki, Hiroshi; Yasui, Masaaki; Kure, Hirotaka; Masuya, Goro
The Integrated Design Methodology is strongly required at the conceptual design phase to achieve the highly reliable space transportation systems, especially the propulsion systems, not only in Japan but also all over the world in these days. Because in the past some catastrophic failures caused some losses of mission and vehicle (LOM/LOV) at the operational phase, moreover did affect severely the schedule delays and cost overrun at the later development phase. Design methodology for highly reliable liquid rocket engine is being preliminarily established and investigated in this study. The sensitivity analysis is systematically performed to demonstrate the effectiveness of this methodology, and to clarify and especially to focus on the correlation between the combustion chamber, turbopump and main valve as main components. This study describes the essential issues to understand the stated correlations, the need to apply this methodology to the remaining critical failure modes in the whole engine system, and the perspective on the engine development in the future.
[Physiotherapy for juvenile idiopathic arthritis].
Spamer, M; Georgi, M; Häfner, R; Händel, H; König, M; Haas, J-P
2012-07-01
Control of disease activity and recovery of function are major issues in the treatment of children and adolescents suffering from juvenile idiopathic arthritis (JIA). Functional therapies including physiotherapy are important components in the multidisciplinary teamwork and each phase of the disease requires different strategies. While in the active phase of the disease pain alleviation is the main focus, the inactive phase requires strategies for improving motility and function. During remission the aim is to regain general fitness by sports activities. These phase adapted strategies must be individually designed and usually require a combination of different measures including physiotherapy, occupational therapy, massage as well as other physical procedures and sport therapy. There are only few controlled studies investigating the effectiveness of physical therapies in JIA and many strategies are derived from long-standing experience. New results from physiology and sport sciences have contributed to the development in recent years. This report summarizes the basics and main strategies of physical therapy in JIA.
Olivo, Alessandro; Robinson, Ian
2014-03-06
A double event, supported as part of the Royal Society scientific meetings, was organized in February 2013 in London and at Chicheley Hall in Buckinghamshire by Dr A. Olivo and Prof. I. Robinson. The theme that joined the two events was the use of X-ray phase in novel imaging approaches, as opposed to conventional methods based on X-ray attenuation. The event in London, led by Olivo, addressed the main roadblocks that X-ray phase contrast imaging (XPCI) is encountering in terms of commercial translation, for clinical and industrial applications. The main driver behind this is the development of new approaches that enable XPCI, traditionally a synchrotron method, to be performed with conventional laboratory sources, thus opening the way to its deployment in clinics and industrial settings. The satellite meeting at Chicheley Hall, led by Robinson, focused on the new scientific developments that have recently emerged at specialized facilities such as third-generation synchrotrons and free-electron lasers, which enable the direct measurement of the phase shift induced by a sample from intensity measurements, typically in the far field. The two events were therefore highly complementary, in terms of covering both the more applied/translational and the blue-sky aspects of the use of phase in X-ray research.
2009-11-30
Son blueberry fields as shown in Figure 113. All FAA and Maine DOT permits were acquired. Richard Willey was the designated LSO (Launch Safety...The launch area is on the Jasper Wyman & Son blueberry fields as shown in Figure 113. FAA and Maine DOT permits are required for flight testing
VLT enclosures: design and construction
NASA Astrophysics Data System (ADS)
Schneermann, Michael W.; Marchiori, Gianpietro; Dimichino, Francesco
1997-03-01
The VLT enclosures main functions are to protect the telescopes during operational as well as non-operational phases from any adverse weather conditions and to provide optimal conditions for observation. An adequate design of a ventilation and wind protection system is important for the performance of the enclosures with respect to the minimization of the corresponding seeing effects. The VLT enclosures are equipped with ventilation doors on the azimuth platform level, with louvers on the rotating part and with a windscreen at the observing slit. Extensive qualification tests of the louvers and windscreen mechanical assemblies have been performed during the enclosures development phase. This paper gives an overview over the general layout of the enclosures and the major subsystems, summarizes the main functional specifications and gives the main results and conclusions of the functional performance tests. Presently the first enclosure erection is nearing its completion and pre- commissioning of all systems will commence. The status of the site erection of the enclosures is presented and the planning for the next phases of the erection is presented.
Low cost carbon fiber technology development for carbon fiber composite applications : phase 1.
DOT National Transportation Integrated Search
2008-01-01
The main goals of this research program at UTSI were: 1) to produce low cost carbon fibers and 2) to develop specific carbonbased : material technologies to meet current and future high performance fiber-reinforced composite needs of FTA and other : ...
Molecular Architecture for Reagentless Immunosensors
1990-11-01
emphasis on electrochemical signal detection, will be developed. Phase II will be mainly devoted to manufacture development and to clinical trials ...Arbor, MI 48104 Ju - Py- Dis-tri~ l AvV ’. : Cedes :Diet . Schramm & Lawton 24665-LS The overall objective of this project was to investigate new
DOT National Transportation Integrated Search
1999-06-01
The main purpose of Phase I of this project was to develop a methodology for predicting consequences of hazardous material (HM) crashes, such as injuries and property damage. An initial step in developing a risk assessment is to reliably estimate the...
ERIC Educational Resources Information Center
Samo, Damianus D.; Darhim; Kartasasmita, Bana
2017-01-01
The purpose of this research is to develop contextual mathematical thinking learning model which is valid, practical and effective based on the theoretical reviews and its support to enhance higher-order thinking ability. This study is a research and development (R & D) with three main phases: investigation, development, and implementation.…
NASA Astrophysics Data System (ADS)
Mouikis, C.; Bingham, S.; Kistler, L. M.; Farrugia, C. J.; Spence, H. E.; Gkioulidou, M.
2016-12-01
The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CME's), co-rotating interaction regions (CIR's), high-speed streamers and other structures. The resulting changes in the ring current particle pressure change the global magnetic field, which affects the transport of the radiation belts. In order to determine the field changes during a storm, it is necessary to understand the transport, sources and losses of the particles that contribute to the ring current. The source population of the storm time ring current is the night side plasma sheet. We use Van Allen Probes observations to determine the ring current pressure contribution of the convecting plasma sheet H+ and O+ particles in the storm time development of the ring current. We compare storms that are related to different interplanetary drivers, CMEs and CIRs, as observed at different local times. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L 2 and their pressure compares to the local magnetic field pressure as deep as L 3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current. However, the largest difference between the CME and CIR ring current responses during the storm main and early recovery phases is caused by how the 15 - 60 keV O+ responds to these drivers.
Aerothermal modeling program, phase 2
NASA Technical Reports Server (NTRS)
Mongia, H. C.; Patankar, S. V.; Murthy, S. N. B.; Sullivan, J. P.; Samuelsen, G. S.
1985-01-01
The main objectives of the Aerothermal Modeling Program, Phase 2 are: to develop an improved numerical scheme for incorporation in a 3-D combustor flow model; to conduct a benchmark quality experiment to study the interaction of a primary jet with a confined swirling crossflow and to assess current and advanced turbulence and scalar transport models; and to conduct experimental evaluation of the air swirler interaction with fuel injectors, assessments of current two-phase models, and verification the improved spray evaporation/dispersion models.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alexandrov, D. V., E-mail: Dmitri.Alexandrov@usu.ru; Ivanov, A. A.
2009-05-15
The process of solidification of ternary systems in the presence of moving phase transition regions has been investigated theoretically in terms of the nonlinear equation of the liquidus surface. A mathematical model is developed and an approximate analytical solution to the Stefan problem is constructed for a linear temperature profile in two-phase zones. The temperature and impurity concentration distributions are determined, the solid-phase fractions in the phase transition regions are obtained, and the laws of motion of their boundaries are established. It is demonstrated that all boundaries move in accordance with the laws of direct proportionality to the square rootmore » of time, which is a general property of self-similar processes. It is substantiated that the concentration of an impurity of the substance undergoing a phase transition only in the cotectic zone increases in this zone and decreases in the main two-phase zone in which the other component of the substance undergoes a phase transition. In the process, the concentration reaches a maximum at the interface between the main two-phase zone and the cotectic two-phase zone. The revealed laws of motion of the outer boundaries of the entire phase transition region do not depend on the amount of the components under consideration and hold true for crystallization of a multicomponent system.« less
Implementation of a Proficiency-Based Diploma System in Maine: Phase II--District Level Analysis
ERIC Educational Resources Information Center
Silvernail, David L.; Stump, Erika K.; McCafferty, Anita Stewart; Hawes, Kathryn M.
2014-01-01
This report describes the findings from Phase II of a study of Maine's implementation of a proficiency-based diploma system. At the request of the Joint Standing Committee on Education and Cultural Affairs of the Maine Legislature, the Maine Policy Research Institute (MEPRI) has conducted a two-phased study of the implementation of Maine law…
A study of space-rated connectors using a robot end-effector
NASA Technical Reports Server (NTRS)
Nguyen, Charles C.
1995-01-01
The main research activities have been directed toward the study of the Robot Operated Materials Processing System (ROMPS), developed at GSFC under a flight project to investigate commercially promising in-space material processes and to design reflyable robot automated systems to be used in the above processes for low-cost operations. The research activities can be divided into two phases. Phase 1 dealt with testing of ROMPS robot mechanical interfaces and compliant device using a Stewart Platform testbed and Phase 2 with computer simulation study of the ROMPS robot control system. This report provides a summary of the results obtained in Phase 1 and Phase 2.
NASA Astrophysics Data System (ADS)
Avetisyan, A. R.; Lazarev, L. Ya.
2017-07-01
This article is a brief overview of some scientific and engineering ideas in the sphere of two-phase gas dynamics that were developed by the team of the Problem Laboratory of Turbomachines, Department of Steam and Gas Turbines, Moscow Power Engineering Institute (NRU MPEI, National Research University), under the leadership of Mikhail Efimovich Deich since 1963 and the analysis of their development and influence on the current state of the problem. At the early stages of the studies on two-phase media, the problem of the measurement of physical parameters of phases was especially urgent. The characteristics of probes for the measurement of one-phase flows in the presence of drops were studied, and the corrections for the influence of the second phase were obtained. However, the main focus was the development of new methods, and the optical method using a laser light source that is currently used at the leading laboratories of the world was chosen as the main method. The study of the wet-steam flow in nozzles is one of the first stages of the research on the problem. In these studies, the wave structure of supersonic wet-steam flows (condensation jumps and shock waves, Mach waves, turbulent condensation, periodic condensation nonstationarity, etc.) was investigated in detail. At present, like in the earlier studies, much attention is paid to the study of the influence of the addition of surface-active substance (SASs) on the wet-steam flow. The study of the wet-steam motion in steam-turbine stages was performed simultaneously with physical studies as the practical application of the obtained results. The development of computer technology in the 21st century contributed to the elaboration of the theoretical methods for the calculation of wet-steam flows in elements of power devices.
Airfoil Vibration Dampers program
NASA Technical Reports Server (NTRS)
Cook, Robert M.
1991-01-01
The Airfoil Vibration Damper program has consisted of an analysis phase and a testing phase. During the analysis phase, a state-of-the-art computer code was developed, which can be used to guide designers in the placement and sizing of friction dampers. The use of this computer code was demonstrated by performing representative analyses on turbine blades from the High Pressure Oxidizer Turbopump (HPOTP) and High Pressure Fuel Turbopump (HPFTP) of the Space Shuttle Main Engine (SSME). The testing phase of the program consisted of performing friction damping tests on two different cantilever beams. Data from these tests provided an empirical check on the accuracy of the computer code developed in the analysis phase. Results of the analysis and testing showed that the computer code can accurately predict the performance of friction dampers. In addition, a valuable set of friction damping data was generated, which can be used to aid in the design of friction dampers, as well as provide benchmark test cases for future code developers.
ERIC Educational Resources Information Center
Silverman, Mitchell
Reported are the first phase activities of a longitudinal project designed to evaluate the effectiveness of Guided Group Interaction (GGI) technique as a meaningful approach in the field of corrections. The main findings relate to the establishment of reliability for the main components of the Revised Behavior Scores System developed to assess the…
James Bacon; Robert Manning; Steven Lawson; William Valliere; Daniel Laven
2003-01-01
A multi-year research initiative was undertaken to inform park planning and management efforts at the Schoodic Peninsula Section of Acadia National Park, Maine. This research focused on developing information that will enable formulation of indicators and standards of quality. The first phase of research in the summer of 2000 obtained descriptive information on visitor...
Characterization of organic compounds in biochars derived from municipal solid waste.
Taherymoosavi, Sarasadat; Verheyen, Vince; Munroe, Paul; Joseph, Stephen; Reynolds, Alicia
2017-09-01
Municipal solid waste (MSW) generation has been growing in many countries, which has led to numerous environmental problems. Converting MSW into a valuable biochar-based by-product can manage waste and, possibly, improve soil fertility, depending on the soil properties. In this study, MSW-based biochars, collected from domestic waste materials and kerbsides in two Sydney's regions, were composted and pyrolysed at 450°C, 550°C and 650°C. The characteristics of the organic components and their interactions with mineral phases were investigated using a range of analytical techniques, with special attention given to polycyclic aromatic hydrocarbons and heavy metal concentrations. The MSW biochar prepared at 450°C contained the most complex organic compounds. The highest concentration of fixed C, indicating the stability of biochar, was detected in the high-temperature-biochar. Microscopic analysis showed development of pores and migration of mineral phases, mainly Ca/P/O-rich phases, into the micro-pores and Si/Al/O-rich phases on the surface of the biochar in the MSW biochar produced at 550°C. Amalgamation of organic phases with mineral compounds was observed, at higher pyrolysis temperatures, indicating chemical reactions between these two phases at 650°C. XPS analysis showed the main changes occurred in C and N bonds. During heat treatment, N-C/C=N functionalities decomposed and oxidized N configurations, mainly pyridine-N-oxide groups, were formed. The majority of the dissolved organic carbon fraction in both MSW biochar produced at 450°C and 550°C was in the form of building blocks, whereas LMW acids was the main fraction in high-temperature-biochar (59.9%). Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bingham, S.; Mouikis, C.; Kistler, L. M.; Fok, M. C. H.; Glocer, A.; Farrugia, C. J.; Gkioulidou, M.; Spence, H. E.
2016-12-01
The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CMEs), and co-rotating interaction regions (CIRs). Delineating the differences in the ring current development between these two drivers will aid our understanding of the ring current dynamics. Using Van Allen Probes observations, we develop an empirical ring current model of the ring current pressure, the pressure anisotropy and the current density development during the storm phases for both types of storm drivers and for all MLTs inside L 6. In addition, we identify the populations (energy and species) responsible. We find that during the storm main phase and the early recovery phase the plasma sheet particles (10-80 keV) convecting from the nightside contribute the most on the ring current pressure and current density. However, during these phases, the main difference between CMEs and CIRs is in the O+ contribution. This empirical model is compared to the results of CIMI simulations of CMEs and CIRs where the model input is comprised of the superposed epoch solar wind conditions of the storms that comprise the empirical model, while different inner magnetosphere boundary conditions will be tested in order to match the empirical model results. Comparing the model and simulation results will fill our understanding of the ring current dynamics as part of the highly coupled inner magnetosphere system.
Short-term hydro generation and interchange contract scheduling for Swiss Rail
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christoforidis, M.; Awobamise, B.; Tong, S.
This paper describes the Short-Term Resource Scheduling (STRS) function that has been developed by Siemens-Empros as part of the new SBB/Direktion Kraftwerk (Swiss Rail) Energy Management System. Optimal scheduling of the single-phase hydro plants, single-phase and three-phase energy accounts, and purchase and sale of three phase energy subject to a multitude of physical and contractual constraints (including spinning and regulating reserve requirements), is the main objective of the STRS function. The operations planning horizon of STRS is one day to one week using an hourly time increment.
Recent development of ionic liquid stationary phases for liquid chromatography.
Shi, Xianzhe; Qiao, Lizhen; Xu, Guowang
2015-11-13
Based on their particular physicochemical characteristics, ionic liquids have been widely applied in many fields of analytical chemistry. Many types of ionic liquids were immobilized on a support like silica or monolith as stationary phases for liquid chromatography. Moreover, different approaches were developed to bond covalently ionic liquids onto the supporting materials. The obtained ionic liquid stationary phases show multi-mode mechanism including hydrophobic, hydrophilic, hydrogen bond, anion exchange, π-π, and dipole-dipole interactions. Therefore, they could be used in different chromatographic modes including ion-exchange, RPLC, NPLC and HILIC to separate various classes of compounds. This review mainly summarizes the immobilized patterns and types of ionic liquid stationary phases, their retention mechanisms and applications in the recent five years. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Mouikis, Christopher; Bingham, Samuel; Kistler, Lynn; Spence, Harlan; Gkioulidou, Matina
2017-04-01
The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CME's), and co-rotating interaction regions (CIR's). Using Van Allen Probes observations, we develop an empirical ring current model of the ring current pressure, the pressure anisotropy and the current density development during the storm phases for both types of storm drivers and for all MLTs inside L 6. Delineating the differences in the ring current development between these two drivers will aid our understanding of the ring current dynamics. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L 2 and their pressure compares to the local magnetic field pressure as deep as L 3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current. However, the largest difference between the CME and CIR ring current responses during the storm main and early recovery phases is caused by how the 15 - 60 keV O+ responds to these drivers. This empirical model is compared to the results of CIMI simulations of a CMEs and a CIRs where the model input is comprised of the superposed epoch solar wind conditions of the storms that comprise the empirical model. Different inner magnetosphere boundary conditions are tested in order to match the empirical model results. Comparing the model and simulation results improves our understanding of the ring current dynamics as part of the highly coupled inner magnetosphere system. In addition, within the framework of this empirical model, the prediction of the EMIC wave generation linear theory is tested using the observed plasma parameters and comparing with the observations of EMIC waves.
NASA Astrophysics Data System (ADS)
Widowati, A.; Anjarsari, P.; Zuhdan, K. P.; Dita, A.
2018-03-01
The challenges of the 21st century require innovative solutions. Education must able to make an understanding of science learning that leads to the formation of scientific literacy learners. This research was conducted to produce the prototype as science worksheet based on Nature of Science (NoS) within inquiry approach and to know the effectiveness its product for developing scientific literacy. This research was the development and research design, by pointing to Four D models and Borg & Gall Model. There were 4 main phases (define, design, develop, disseminate) and additional phases (preliminary field testing, main product revision, main field testing, and operational product revision). Research subjects were students of the junior high school in Yogyakarta. The instruments used included questionnaire sheet product validation and scientific literacy test. For the validation data were analyzed descriptively. The test result was analyzed by an N-gain score. The results showed that the appropriateness of worksheet applying NoS within inquiry-based learning approach is eligible based on the assessment from excellent by experts and teachers, students’ scientific literacy can improve high category of the N-gain score at 0.71 by using student worksheet with Nature of Science (NoS) within inquiry approach.
The Role of Social Support in Dance Talent Development
ERIC Educational Resources Information Center
Chua, Joey
2015-01-01
This multiple case study aims to answer the main research question, "How well are exceptionally talented Finnish and Singaporean dance students supported by significant individuals at different phases of the students' development?" The exceptionally talented students aged 16 to 22 were enrolled in their national dance institutions--the…
a Calorimetric Study of the Precipitation Hardening Mechanisms in AN Al-Cu-Mg-Si Alloy
NASA Astrophysics Data System (ADS)
Hayoune, Abdelali
2013-08-01
The precipitation phenomena and the related hardening in an Al-Cu-Mg-Si alloy were studied by calorimetry, X-ray diffraction analysis and microhardness measurements. The main calorimetric peaks were identified to be due to β‧‧, θ‧ and Q‧ phases precipitation. The hardening during aging at room temperature and 160°C, was respectively, explained by atomic clusters and GP zones formation and by GP zones and β‧‧/θ‧ phases coprecipitation. Although the mechanical properties variation during aging at 200°C is simple, the corresponding microstructural evolution is complex: on the basis of the DSC results, the increasing of microhardness values, is mainly due to the coprecipitation of GP zones and β‧‧/θ‧ phases, however, the maximum hardening is explained by the coexistence of β‧‧/θ‧ and θ‧‧ phases. Another important conclusion is that during aging at 160°C and 200°C, the θ‧ phase is essentially developed from GP zones.
NASA Astrophysics Data System (ADS)
Castillo Vincentelli, Maria Gabriela; Favoreto, Julia; Roemers-Oliveira, Eduardo
2018-02-01
An integrated geophysical and geological analysis of a carbonate reservoir can offer an effective method to better understand the paleogeographical evolution and distribution of a geological reservoir and non-reservoir facies. Therefore, we propose a better method for obtaining geological facies from geophysical facies, helping to characterize the permo-porous system of this kind of play. The goal is to determine the main geological phases from a specific hydrocarbon producer (Albian Campos Basin, Brazil). The applied method includes the use of a petrographic and qualitative description from the integrated reservoir with seismic interpretation of an attribute map (energy, root mean square, mean amplitude, maximum negative amplitude, etc), all calculated at the Albian level for each of the five identified phases. The studied carbonate reservoir is approximately 6 km long with a main direction of NE-SW, and it was sub-divided as follows (from bottom to top): (1) the first depositional sequence of the bank was composed mainly of packstone, indicating that the local structure adjacent to the main bank is protected from environmental conditions; (2) characterized by the presence of grainstone developed at the higher structure; (3) the main sequence of the peloidal packstone with mudstones oncoids; (4) corresponds to the oil production of carbonate reservoirs formed by oolitic grainstone deposited at the top of the carbonate bank; at this phase, rising sea levels formed channels that connected the open sea shelf with the restricted circulation shelf; and (5) mudstone and wackestone represent the system’s flooding phase.
NASA Astrophysics Data System (ADS)
1990-09-01
The main purpose of the International Thermonuclear Experimental Reactor (ITER) is to develop an experimental fusion reactor through the united efforts of many technologically advanced countries. The ITER terms of reference, issued jointly by the European Community, Japan, the USSR, and the United States, call for an integrated international design activity and constitute the basis of current activities. Joint work on ITER is carried out under the auspices of the International Atomic Energy Agency (IAEA), according to the terms of quadripartite agreement reached between the European Community, Japan, the USSR, and the United States. The site for joint technical work sessions is at the Max Planck Institute of Plasma Physics. Garching, Federal Republic of Germany. The ITER activities have two phases: a definition phase performed in 1988 and the present design phase (1989 to 1990). During the definition phase, a set of ITER technical characteristics and supporting research and development (R and D) activities were developed and reported. The present conceptual design phase of ITER lasts until the end of 1990. The objectives of this phase are to develop the design of ITER, perform a safety and environmental analysis, develop site requirements, define future R and D needs, and estimate cost, manpower, and schedule for construction and operation. A final report will be submitted at the end of 1990. This paper summarizes progress in the ITER program during the 1989 design phase.
Chang, Chung-Liang; Sie, Ming-Fong; Shie, Jin-Long
2011-01-01
This paper presents the design concept of a bio-botanic robot which demonstrates its behavior based on plant growth. Besides, it can reflect the different phases of plant growth depending on the proportional amounts of light, temperature and water. The mechanism design is made up of a processed aluminum base, spring, polydimethylsiloxane (PDMS) and actuator to constitute the plant base and plant body. The control system consists of two micro-controllers and a self-designed embedded development board where the main controller transmits the values of the environmental sensing module within the embedded board to a sub-controller. The sub-controller determines the growth stage, growth height, and time and transmits its decision value to the main controller. Finally, based on the data transmitted by the sub-controller, the main controller controls the growth phase of the bio-botanic robot using a servo motor and leaf actuator. The research result not only helps children realize the variation of plant growth but also is entertainment-educational through its demonstration of the growth process of the bio-botanic robot in a short time.
DAG: a new observatory and a prospective observing site for other potential telescopes
NASA Astrophysics Data System (ADS)
Yeşilyaprak, Cahit; Yerli, Sinan K.; Keskin, Onur; Güçsav, B. Bülent
2016-07-01
DAG (Eastern Anatolia Observatory is read as "Doğu Anadolu Gözlemevi" in Turkish) is the newest and largest observatory of Turkey, constructed at an altitude of 3150 m in Konaklı/Erzurum provenience, with an optical and nearinfrared telescope (4 m in diameter) and its robust observing site infrastructure. This national project consists of three main phases: DAG (Telescope, Enclosure, Buildings and Infrastructures), FPI (Focal Plane Instruments and Adaptive Optics) and MCP (Mirror Coating Plant). All these three phases are supported by the Ministry of Development of Turkey and funding is awarded to Atatürk University. Telescope, enclosure and building tenders were completed in 2014, 2015 and 2016, respectively. The final design of telescope, enclosure and building and almost all main infrastructure components of DAG site have been completed; mainly: road work, geological and atmospheric surveys, electric and fiber cabling, water line, generator system, cable car to summit. This poster explains recent developments of DAG project and talks about the future possible collaborations for various telescopes which can be constructed at the site.
Generation of phase edge singularities by coplanar three-beam interference and their detection.
Patorski, Krzysztof; Sluzewski, Lukasz; Trusiak, Maciej; Pokorski, Krzysztof
2017-02-06
In recent years singular optics has gained considerable attention in science and technology. Up to now optical vortices (phase point dislocations) have been of main interest. This paper presents the first general analysis of formation of phase edge singularities by coplanar three-beam interference. They can be generated, for example, by three-slit interference or self-imaging in the Fresnel diffraction field of a sinusoidal grating. We derive a general condition for the ratio of amplitudes of interfering beams resulting in phase edge dislocations, lateral separation of dislocations depends on this ratio as well. Analytically derived properties are corroborated by numerical and experimental studies. We develop a simple, robust, common path optical self-imaging configuration aided by a coherent tilted reference wave and spatial filtering. Finally, we propose an automatic fringe pattern analysis technique for detecting phase edge dislocations, based on the continuous wavelet transform. Presented studies open new possibilities for developing grating based sensing techniques for precision metrology of very small phase differences.
Applications of phase-contrast x-ray imaging to medicine using an x-ray interferometer
NASA Astrophysics Data System (ADS)
Momose, Atsushi; Yoneyama, Akio; Takeda, Tohoru; Itai, Yuji; Tu, Jinhong; Hirano, Keiichi
1999-10-01
We are investigating possible medical applications of phase- contrast X-ray imaging using an X-ray interferometer. This paper introduces the strategy of the research project and the present status. The main subject is to broaden the observation area to enable in vivo observation. For this purpose, large X-ray interferometers were developed, and 2.5 cm X 1.5 cm interference patterns were generated using synchrotron X-rays. An improvement of the spatial resolution is also included in the project, and an X-ray interferometer designed for high-resolution phase-contrast X-ray imaging was fabricated and tested. In parallel with the instrumental developments, various soft tissues are observed by phase- contrast X-ray CT to find correspondence between the generated contrast and our histological knowledge. The observation done so far suggests that cancerous tissues are differentiated from normal tissues and that blood can produce phase contrast. Furthermore, this project includes exploring materials that modulate phase contrast for selective imaging.
Development of the RFBB “Bargouzine” concept for Ariane-5 evolution
NASA Astrophysics Data System (ADS)
Sumin, Yuriy; Kostromin, Sergey F.; Panichkin, Nikolai; Prel, Yves; Osin, Mikhail; Iranzo-Greus, David; Prampolini, Marco
2009-10-01
This paper presents the study of a concept of Ariane-5 evolution by means of replacement of two solid-propellant boosters EAP with two liquid-propellant reusable fly-back boosters (RFBBs) called "Bargouzine". The main design feature of the reference RFBB is LOX/LH2 propellant, the canard aerodynamic configuration with delta wings and rocket engines derived from Vulcain-2 identical to that of the central core except for the nozzle length. After separation RFBBs return back by use of air breathing engines mounted in the aft part and then landing on a runway. The aim of the study is a more detailed investigation of critical technology issues concerning reliability, re-usability and maintenance requirements. The study was performed in three main phases: system trade-off, technical consolidation, and programmatic synthesis. The system trade-off includes comparative analysis of two systems with three and four engines on each RFBB and determination of the necessary thrust level taking into account thrust reservation for emergency situations. Besides, this phase contains trade-off on booster aerodynamic configurations and abort scenario analysis. The second phase includes studying of controllability during the ascent phase and separation, thermo-mechanical design, development of ground interfaces and attachment means, and turbojets engine analysis taking into account reusability.
NASA Astrophysics Data System (ADS)
Behrens, J.; Ranitzsch, P. C.-O.; Beck, M.; Beglarian, A.; Erhard, M.; Groh, S.; Hannen, V.; Kraus, M.; Ortjohann, H.-W.; Rest, O.; Schlösser, K.; Thümmler, T.; Valerius, K.; Wierman, K.; Wilkerson, J. F.; Winzen, D.; Zacher, M.; Weinheimer, C.
2017-06-01
The KATRIN experiment aims to determine the neutrino mass scale with a sensitivity of 200 {meV/c^2} (90% C. L.) by a precision measurement of the shape of the tritium β -spectrum in the endpoint region. The energy analysis of the decay electrons is achieved by a MAC-E filter spectrometer. To determine the transmission properties of the KATRIN main spectrometer, a mono-energetic and angular-selective electron source has been developed. In preparation for the second commissioning phase of the main spectrometer, a measurement phase was carried out at the KATRIN monitor spectrometer where the device was operated in a MAC-E filter setup for testing. The results of these measurements are compared with simulations using the particle-tracking software "Kassiopeia", which was developed in the KATRIN collaboration over recent years.
Developing a holistic accreditation system for medical universities of the Islamic Republic of Iran.
Yousefy, A; Changiz, T; Yamani, N; Zahrai, R H; Ehsanpour, S
2009-01-01
This report describes the steps in the development of an accreditation system for medical universities in the Islamic Republic of Iran. The national accreditation project, supported by the government, was performed from 2001 to 2005. The project was carried out in 3 main phases, each phase including a number of tasks. After a review of the international literature on accreditation and through national consensus, a set of national institutional accreditation standards was developed, including 95 standards and 504 indicators in 10 areas. By complying with accepted national standards, Iranian medical universities will play an important role in promoting health system performance.
Possible impacts of climate change on natural vegetation in Saxony (Germany).
Chmielewski, Frank M; Müller, Antje; Küchler, Wilfried
2005-11-01
Recent climate changes have had distinct impacts on plant development in many parts of the world. Higher air temperatures, mainly since the end of the 1980s, have led to advanced timing of phenological phases and consequently to an extension of the general growing season. For this reason it is interesting to know how plants will respond to future climate change. In this study simple phenological models have been developed to estimate the impact of climate change on the natural vegetation in Saxony. The estimations are based on a regional climate scenario for the state of Saxony. The results indicate that changes in the timing of phenophases could continue in the future. Due to distinct temperature changes in winter and in summer, mainly the spring and summer phases will be advanced. Spring phenophases, such as leafing or flowering, show the strongest trends. Depending on the species, the average timing of these phenophases could be advanced by 3-27 days by 2050. Phenophases in autumn show relatively small changes. Thus, the annual growth period of individual trees will be further extended, mainly because of the shift of spring phases. Frequent droughts in summer and in autumn can compensate for the earlier leafing of trees, because in this case leaf colouring and leaf fall would start some weeks earlier. In such cases, the growing period would not be really extended, but shifted to the beginning of the year.
ERIC Educational Resources Information Center
Restrepo, M. Adelaida; Gorin, Joanna S.; Gray, Shelley; Morgan, Gareth P.; Barona, Nicole
2010-01-01
The main purpose of this study is to develop a Spanish language screening measure that (a) is valid and reliable for the purpose of identifying Spanish-speaking (SS) children at risk for Language Impairment (LI), (b) is valid and reliable across different Spanish dialects, different socioeconomic groups, and different ethnicities, (c) uses a…
Best Practices for Competency Development and Assessment in Higher Education
ERIC Educational Resources Information Center
Redondo Duarte, Sara; Learreta Ramos, Begoña; Ruiz Rosillo, María Auxiliadora; Alperstedt, Cristiane; Hazé, Emmanuël
2015-01-01
The main objective of this article is to present the results of a study aimed at determining, classifying and evaluating practices of interest for general competency development and assessment in undergraduate programmes. The study encompassed the following phases: (1) focus group in order to establish a starting point regarding competency…
Turrero García, Miguel; Chang, YoonJeung; Arai, Yoko; Huttner, Wieland B
2016-02-15
The evolutionary expansion of the neocortex primarily reflects increases in abundance and proliferative capacity of cortical progenitors and in the length of the neurogenic period during development. Cell cycle parameters of neocortical progenitors are an important determinant of cortical development. The ferret (Mustela putorius furo), a gyrencephalic mammal, has gained increasing importance as a model for studying corticogenesis. Here, we have studied the abundance, proliferation, and cell cycle parameters of different neural progenitor types, defined by their differential expression of the transcription factors Pax6 and Tbr2, in the various germinal zones of developing ferret neocortex. We focused our analyses on postnatal day 1, a late stage of cortical neurogenesis when upper-layer neurons are produced. Based on cumulative 5-ethynyl-2'-deoxyuridine (EdU) labeling as well as Ki67 and proliferating cell nuclear antigen (PCNA) immunofluorescence, we determined the duration of the various cell cycle phases of the different neocortical progenitor subpopulations. Ferret neocortical progenitors were found to exhibit longer cell cycles than those of rodents and little variation in the duration of G1 among distinct progenitor types, also in contrast to rodents. Remarkably, the main difference in cell cycle parameters among the various progenitor types was the duration of S-phase, which became shorter as progenitors progressively changed transcription factor expression from patterns characteristic of self-renewal to those of neuron production. Hence, S-phase duration emerges as major target of cell cycle regulation in cortical progenitors of this gyrencephalic mammal. © 2015 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.
A novel ultrasonic phased array inspection system to NDT for offshore platform structures
NASA Astrophysics Data System (ADS)
Wang, Hua; Shan, Baohua; Wang, Xin; Ou, Jinping
2007-01-01
A novel ultrasonic phased array detection system is developed for nondestructive testing (NDT). The purpose of the system is to make acquisition of data in real-time from 64-element ultrasonic phased array transducer, and to enable real- time processing of the acquired data. The system is composed of five main parts: master unit, main board, eight transmit/receive units, a 64-element transducer and an external PC. The system can be used with 64 element transducers, excite 32 elements, receive and sample echo signals form 32 elements simultaneously at 62.5MHz with 8 bit precision. The external PC is used as the user interface showing the real time images and controls overall operation of the system through USB serial link. The use of Universal Serial Bus (USB) improves the transform speed and reduces hardware interface complexity. The program of the system is written in Visual C++.NET and is platform independent.
Free-Piston Stirling Power Conversion Unit for Fission Power System, Phase II Final Report
NASA Technical Reports Server (NTRS)
Wood, J. Gary; Stanley, John
2016-01-01
In Phase II, the manufacture and testing of two 6-kW(sub e)Stirling engines was completed. The engines were delivered in an opposed 12-kW(sub e) arrangement with a common expansion space heater head. As described in the Phase I report, the engines were designed to be sealed both hermetically and with a bolted O-ring seal. The completed Phase II convertor is in the bolted configuration to allow future disassembly. By the end of Phase II, the convertor had passed all of the final testing requirements in preparation for delivery to the NASA Glenn Research Center. The electronic controller also was fabricated and tested during Phase II. The controller sets both piston amplitudes and maintains the phasing between them. It also sets the operating frequency of the machine. Details of the controller are described in the Phase I final report. Fabrication of the direct-current to direct-current (DC-DC) output stage, which would have stepped down the main controller output voltage from 700 to 120 V(sub DC), was omitted from this phase of the project for budgetary reasons. However, the main controller was successfully built, tested with the engines, and delivered. We experienced very few development issues with this high-power controller. The project extended significantly longer than originally planned because of yearly funding delays. The team also experienced several hardware difficulties along the development path. Most of these were related to the different thermal expansions of adjacent parts constructed of different materials. This issue was made worse by the large size of the machine. Thermal expansion problems also caused difficulties in the brazing of the opposed stainless steel sodium-potassium (NaK) heater head. Despite repeated attempts Sunpower was not able to successfully braze the opposed head under this project. Near the end of the project, Glenn fabricated an opposed Inconel NaK head, which was installed prior to delivery for testing at Glenn. Engine development prior to this was performed using both single- and dual-opposed (common expansion space) Inconel heads with clamp-on electric heaters.
Imbibition of wheat seeds: Application of image analysis
NASA Astrophysics Data System (ADS)
Lev, Jakub; Blahovec, Jiří
2017-10-01
Image analysis is widely used for monitoring seeds during germination, and it is often the final phase of germination that is subjected to the greatest attention. However, the initial phase of germination (the so-called imbibition) also exhibits interesting behaviour. This work shows that image analysis has significant potential in the imbibition. Herein, a total of 120 seeds were analysed during germination tests, and information about seed size and shape was stored and analysed. It was found that the imbibition can be divided into two newly defined parts. The first one (`abrupt imbibition') consists mainly of the swelling of the seed embryo part and lasts approximately one hour. The second one, referred to as `main imbibition', consists mainly of spatial expansion caused by imbibition in the other parts of the seed. The results presented are supported by the development of seed cross area and shape parameters, and by direct observation.
Orbit transfer rocket engine technology program. Phase 2: Advanced engine study
NASA Technical Reports Server (NTRS)
Erickson, C.; Martinez, A.; Hines, B.
1987-01-01
In Phase 2 of the Advanced Engine Study, the Failure Modes and Effects Analysis (FMEA) maintenance-driven engine design, preliminary maintenance plan, and concept for space operable disconnects generated in Phase 1 were further developed. Based on the results of the vehicle contractors Orbit Transfer Vehicle (OTV) Concept Definition and System Analysis Phase A studies, minor revisions to the engine design were made. Additional refinements in the engine design were identified through further engine concept studies. These included an updated engine balance incorporating experimental heat transfer data from the Enhanced Heat Load Thrust Chamber Study and a Rao optimum nozzle contour. The preliminary maintenance plan of Phase 1 was further developed through additional studies. These included a compilation of critical component lives and life limiters and a review of the Space Shuttle Main Engine (SSME) operations and maintenance manual in order to begin outlining the overall maintenance procedures for the Orbit Transfer Vehicle Engine and identifying technology requirements for streamlining space-based operations. Phase 2 efforts also provided further definition to the advanced fluid coupling devices including the selection and preliminary design of a preferred concept and a preliminary test plan for its further development.
NASA Technical Reports Server (NTRS)
Goullioud, Renaud; Dekens, Frank; Nemati, Bijan; An, Xin; Carson, Johnathan
2010-01-01
The SIM Lite Astrometric Observatory is a mission concept for a space-borne instrument to perform micro-arc-second narrow-angle astrometry to search 60 to 100 nearby stars for Earth-like planets, and to perform global astrometry for a broad astrophysics program. The instrument consists of two Michelson stellar interferometers and a telescope. The first interferometer chops between the target star and a set of reference stars. The second interferometer monitors the attitude of the instrument in the direction of the target star. The telescope monitors the attitude of the instrument in the other two directions. The main enabling technology development for the mission was completed during phases A & B. The project is currently implementing the developed technology onto flight-ready engineering models. These key engineering tasks will significantly reduce the implementation risks during the flight phases C & D of the mission. The main optical interferometer components, including the astrometric beam combiner, the fine steering optical mechanism, the path-length-control and modulation optical mechanisms, focal-plane camera electronics and cooling heat pipe, are currently under development. Main assemblies are built to meet flight requirements and will be subjected to flight qualification level environmental testing (random vibration and thermal cycling) and performance testing. This paper summarizes recent progress in engineering risk reduction activities.
An Automatic Phase-Change Detection Technique for Colloidal Hard Sphere Suspensions
NASA Technical Reports Server (NTRS)
McDowell, Mark; Gray, Elizabeth; Rogers, Richard B.
2005-01-01
Colloidal suspensions of monodisperse spheres are used as physical models of thermodynamic phase transitions and as precursors to photonic band gap materials. However, current image analysis techniques are not able to distinguish between densely packed phases within conventional microscope images, which are mainly characterized by degrees of randomness or order with similar grayscale value properties. Current techniques for identifying the phase boundaries involve manually identifying the phase transitions, which is very tedious and time consuming. We have developed an intelligent machine vision technique that automatically identifies colloidal phase boundaries. The algorithm utilizes intelligent image processing techniques that accurately identify and track phase changes vertically or horizontally for a sequence of colloidal hard sphere suspension images. This technique is readily adaptable to any imaging application where regions of interest are distinguished from the background by differing patterns of motion over time.
NASA Technical Reports Server (NTRS)
Banda, Carolyn; Bushnell, David; Chen, Scott; Chiu, Alex; Neukom, Christian; Nishimura, Sayuri; Prevost, Michael; Shankar, Renuka; Staveland, Lowell; Smith, Greg
1992-01-01
This is the Software Concept Document for the Man-machine Integration Design and Analysis System (MIDAS) being developed as part of Phase V of the Army-NASA Aircrew/Aircraft Integration (A3I) Progam. The approach taken in this program since its inception in 1984 is that of incremental development with clearly defined phases. Phase 1 began in 1984 and subsequent phases have progressed at approximately 10-16 month intervals. Each phase of development consists of planning, setting requirements, preliminary design, detailed design, implementation, testing, demonstration and documentation. Phase 5 began with an off-site planning meeting in November, 1990. It is expected that Phase 5 development will be complete and ready for demonstration to invited visitors from industry, government and academia in May, 1992. This document, produced during the preliminary design period of Phase 5, is intended to record the top level design concept for MIDAS as it is currently conceived. This document has two main objectives: (1) to inform interested readers of the goals of the MIDAS Phase 5 development period, and (2) to serve as the initial version of the MIDAS design document which will be continuously updated as the design evolves. Since this document is written fairly early in the design period, many design issues still remain unresolved. Some of the unresolved issues are mentioned later in this document in the sections on specific components. Readers are cautioned that this is not a final design document and that, as the design of MIDAS matures, some of the design ideas recorded in this document will change. The final design will be documented in a detailed design document published after the demonstrations.
Improved Tubulars for Better Economics in Deep Gas Well Drilling Using Microwave Technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinesh Agrawal
2006-09-30
The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joiningmore » (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.« less
Improved Tubulars for Better Economics in Deep Gas Well Drilling using Microwave Technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinesh Agrawal; Paul Gigl; Mark Hunt
2007-07-31
The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joiningmore » (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.« less
Development of a CFD code for casting simulation
NASA Technical Reports Server (NTRS)
Murph, Jesse E.
1993-01-01
Because of high rejection rates for large structural castings (e.g., the Space Shuttle Main Engine Alternate Turbopump Design Program), a reliable casting simulation computer code is very desirable. This code would reduce both the development time and life cycle costs by allowing accurate modeling of the entire casting process. While this code could be used for other types of castings, the most significant reductions of time and cost would probably be realized in complex investment castings, where any reduction in the number of development castings would be of significant benefit. The casting process is conveniently divided into three distinct phases: (1) mold filling, where the melt is poured or forced into the mold cavity; (2) solidification, where the melt undergoes a phase change to the solid state; and (3) cool down, where the solidified part continues to cool to ambient conditions. While these phases may appear to be separate and distinct, temporal overlaps do exist between phases (e.g., local solidification occurring during mold filling), and some phenomenological events are affected by others (e.g., residual stresses depend on solidification and cooling rates). Therefore, a reliable code must accurately model all three phases and the interactions between each. While many codes have been developed (to various stages of complexity) to model the solidification and cool down phases, only a few codes have been developed to model mold filling.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-21
... methodological study is to evaluate the feasibility, acceptability, and cost of three separate recruitment... (NCS). In combination, the studies in the Vanguard Phase will be used to inform the design of the Main...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-17
... preparation needed for a study of this size and complexity, the NCS was designed to include a preliminary... parallel with the Main Study. At every phase of the NCS, the multiple methodological studies conducted...
Maximum heat of mass concrete - phase 2.
DOT National Transportation Integrated Search
2016-11-01
The main findings and recommendations from this study are as follows: : (1) The database of adiabatic temperature rise tables which was developed in this study can be used in the DIANA software for the modeling of mass concrete structures. : (2) Clas...
Field-Aligned Current at Plasma Sheet Boundary Layers During Storm Time: Cluster Observation
NASA Astrophysics Data System (ADS)
Shi, J.; Cheng, Z.; Zhang, T.; Dunlop, M.; Liu, Z.
2007-05-01
The magnetic field data from the FGM instruments on board the four Cluster spacecrafts were used to study Field Aligned Current (FAC) at the Plasma Sheet Boundary Layers (PSBLs) with the so called "curlometer technique". We analyzed the date obtained in 2001 in the magnetotail and only two cases were found in the storm time. One (August 17, 2001) occurred from sudden commencement to main phase, and the other (October 1, 2001) lay in the main phase and recovery phase. The relationship between the FAC density and the AE index was studied and the results are shown as follows. (1) In the sudden commencement and the main phase the density of the FAC increases obviously, in the recovery phase the density of the FAC increases slightly. (2) From the sudden commencement to the initial stage of the main phase the FAC increases with decreasing AE index and decreases with increasing AE index. From the late stage of the main phase to initial stage of the recovery phase, the FAC increases with increasing AE index and decreases with decreasing AE index. In the late stage of the recovery phase the disturbance of the FAC is not so violent, so that the FAC varying with the AE index is not very obvious.
NASA Astrophysics Data System (ADS)
He, Fei; Zhang, Xiao-Xin; Wang, Wenbin; Liu, Libo; Ren, Zhi-Peng; Yue, Xinan; Hu, Lianhuan; Wan, Weixing; Wang, Hui
2018-04-01
In this study, we present multisatellite observations of the large-scale structures of subauroral polarization streams (SAPS) during the main phase of a severe geomagnetic storm that occurred on 31 March 2001. Observations by the Defense Meteorological Satellite Program F12 to F15 satellites indicate that the SAPS were first generated around the dusk sector at the beginning of the main phase. The SAPS channel then expanded toward the midnight sector and moved to lower latitudes as the main phase progressed. The peak velocity, latitudinal width, latitudinal alignment, and longitudinal span of the SAPS channel were highly dynamic during the storm main phase. The large westward velocities of the SAPS were located in the region of low electron densities, associated with low ionospheric conductivity. The large-scale structures of the SAPS also corresponded closely to those of the region-2 field-aligned currents, which were mainly determined by the azimuthal pressure gradient of the ring current.
The plasmasheet H+ and O+ contribution on the storm time ring current
NASA Astrophysics Data System (ADS)
Mouikis, C.; Bingham, S.; Kistler, L. M.; Spence, H. E.; Gkioulidou, M.; Claudepierre, S. G.; Farrugia, C. J.
2015-12-01
The source population of the storm time ring current is the night side plasma sheet. We use Van Allen Probes and Cluster observations to determine the contribution of the convecting plasma sheet H+ and O+ particles in the storm time development of the ring current. Using the Volland-Stern model with a dipole magnetic field together with the identification of the observed energy cutoffs in the particle spectra, we specify the pressure contributed by H+ and O+ populations that are on open drift paths vs. the pressure contributed by the trapped populations, for different local times. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L~2 and their pressure compares to the local magnetic field pressure as deep as L~3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current.
Reproductive Ontogeny of Wheat Grown on the MIR Space Station
NASA Technical Reports Server (NTRS)
Bubenheim, David L.; Stieber, Joseph
1997-01-01
The reproductive ontogeny of 'Super-Dwarf' wheat grown on the space station Mir is chronicled from the vegetative phase through flower development. Changes in the apical meristem associated with transition From the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Filament elongation, which characteristically occurs just prior to anthesis and moves the anthers through the stigmatic branches thus facilitating pollination, did no1 xcur in the flowers of spikes grown on Mir. While development of spikes on tillers typically occurs later :han that of spikes on the main stem, all flowers appear to be arrested at the same developmental point.
Optical Design of the WFIRST Phase-A Integral Field Channel
NASA Technical Reports Server (NTRS)
Gao, Guangjun; Pasquale, Bert A.; Marx, Catherine T.; Chambers, Victor
2017-01-01
WFIRST is one of NASA's Decadal Survey Missions and is currently in Phase-A development. The optical design of the WFIRST Integral Field Channel (IFC), one of three main optical channels of WFIRST, is presented, and the evolution of the IFC channel since Mission Concept Review (MCR, end of Pre-Phase A) is discussed. The IFC has two sub-channels: Supernova (IFC-S) and Galaxy (IFC-G) channels, with Fields of View of 3"x4.5" and 4.2"x9" respectively, and approximately R 75 spectral analysis over waveband 0.42 approximately 2.0 micrometers. The Phase-A IFC optical design meets image quality requirements over the FOV areas while balancing cost and volume constraints.
Advanced Health Management System for the Space Shuttle Main Engine
NASA Technical Reports Server (NTRS)
Davidson, Matt; Stephens, John
2004-01-01
Boeing-Canoga Park (BCP) and NASA-Marshall Space Flight Center (NASA-MSFC) are developing an Advanced Health Management System (AHMS) for use on the Space Shuttle Main Engine (SSME) that will improve Shuttle safety by reducing the probability of catastrophic engine failures during the powered ascent phase of a Shuttle mission. This is a phased approach that consists of an upgrade to the current Space Shuttle Main Engine Controller (SSMEC) to add turbomachinery synchronous vibration protection and addition of a separate Health Management Computer (HMC) that will utilize advanced algorithms to detect and mitigate predefined engine anomalies. The purpose of the Shuttle AHMS is twofold; one is to increase the probability of successfully placing the Orbiter into the intended orbit, and the other is to increase the probability of being able to safely execute an abort of a Space Transportation System (STS) launch. Both objectives are achieved by increasing the useful work envelope of a Space Shuttle Main Engine after it has developed anomalous performance during launch and the ascent phase of the mission. This increase in work envelope will be the result of two new anomaly mitigation options, in addition to existing engine shutdown, that were previously unavailable. The added anomaly mitigation options include engine throttle-down and performance correction (adjustment of engine oxidizer to fuel ratio), as well as enhanced sensor disqualification capability. The HMC is intended to provide the computing power necessary to diagnose selected anomalous engine behaviors and for making recommendations to the engine controller for anomaly mitigation. Independent auditors have assessed the reduction in Shuttle ascent risk to be on the order of 40% with the combined system and a three times improvement in mission success.
Turrero García, Miguel; Chang, YoonJeung; Arai, Yoko
2016-01-01
ABSTRACT The evolutionary expansion of the neocortex primarily reflects increases in abundance and proliferative capacity of cortical progenitors and in the length of the neurogenic period during development. Cell cycle parameters of neocortical progenitors are an important determinant of cortical development. The ferret (Mustela putorius furo), a gyrencephalic mammal, has gained increasing importance as a model for studying corticogenesis. Here, we have studied the abundance, proliferation, and cell cycle parameters of different neural progenitor types, defined by their differential expression of the transcription factors Pax6 and Tbr2, in the various germinal zones of developing ferret neocortex. We focused our analyses on postnatal day 1, a late stage of cortical neurogenesis when upper‐layer neurons are produced. Based on cumulative 5‐ethynyl‐2′‐deoxyuridine (EdU) labeling as well as Ki67 and proliferating cell nuclear antigen (PCNA) immunofluorescence, we determined the duration of the various cell cycle phases of the different neocortical progenitor subpopulations. Ferret neocortical progenitors were found to exhibit longer cell cycles than those of rodents and little variation in the duration of G1 among distinct progenitor types, also in contrast to rodents. Remarkably, the main difference in cell cycle parameters among the various progenitor types was the duration of S‐phase, which became shorter as progenitors progressively changed transcription factor expression from patterns characteristic of self‐renewal to those of neuron production. Hence, S‐phase duration emerges as major target of cell cycle regulation in cortical progenitors of this gyrencephalic mammal. J. Comp. Neurol. 524:456–470, 2016. © 2015 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:25963823
Progressive magmatism and evolution of the Variscan suture in southern Iberia
NASA Astrophysics Data System (ADS)
Braid, James A.; Murphy, J. Brendan; Quesada, Cecilio; Gladney, Evan R.; Dupuis, Nicolle
2018-04-01
Magmatic activity is an integral component of orogenic processes, from arc magmatism during convergence to post-collisional crustal melting. Southern Iberia exposes a Late Paleozoic suture zone within Pangea and where a crustal fragment of Laurussia (South Portuguese Zone) is juxtaposed with parautochthonous Gondwana (Ossa Morena Zone). Fault-bounded oceanic metasedimentary rocks, mélanges and ophiolite complexes characterize the suture zone and are intruded by plutonic rocks and mafic dykes. The generation and emplacement of these intrusive rocks and their relationship to development of the suture zone and the orogen are undetermined. Field evidence combined with U/Pb (zircon) geochronology reveals three main phases of plutonism, a pre-collisional unfoliated gabbroic phase emplaced at ca 354 Ma, crosscut by a syn-tectonic ca 345 Ma foliated granodiorite phase followed by a ca 335 Ma granitic phase. Geochemical analyses (major, trace, rare earth elements) indicate that the gabbro exhibits a calc-alkaline arc signature whereas the granodiorite and granite are typical of post-collisional slab break-off. Taken together, these data demonstrate a protracted development of the orogen and support a complex late stage evolution broadly similar to the tectonics of the modern eastern Mediterranean. In this scenario, the highly oblique closure of a small tract of oceanic lithosphere postdates the main collision event resulting in escape of parautochthonous and allochthonous terranes toward the re-entrant.
Pang, Long; Yang, Peijie; Pang, Rong; Li, Shunyi
2017-08-01
1-Hexadecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide is a solid-phase ionic organic material under ambient temperature and is considered as a kind of "frozen" ionic liquid. Because of their solid-state and ultra-hydrophobicity, "frozen" ionic liquids are able to be confined in the pores of hollow fiber, based on which a simple method was developed for the hollow-fiber solid-phase microextraction of dichlorodiphenyltrichloroethane and its main metabolites. Under optimized conditions, the proposed method results in good linearity (R 2 > 0.9965) over the range of 0.5-50 μg/L, with low limits of detection and quantification in the range of 0.33-0.38 and 1.00-1.25 μg/L, respectively. Intra- and interday precisions evaluated by relative standard deviation were 3-6 and 1-6%, respectively. The spiked recoveries of dichlorodiphenyltrichloroethane and its main metabolites from real water samples were in the range of 64-113 and 79-112%, respectively, at two different concentration levels. The results suggest that "frozen" ionic liquids are promising for use as a class of novel sorbents. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Chang, Chung-Liang; Sie, Ming-Fong; Shie, Jin-Long
2011-01-01
This paper presents the design concept of a bio-botanic robot which demonstrates its behavior based on plant growth. Besides, it can reflect the different phases of plant growth depending on the proportional amounts of light, temperature and water. The mechanism design is made up of a processed aluminum base, spring, polydimethylsiloxane (PDMS) and actuator to constitute the plant base and plant body. The control system consists of two micro-controllers and a self-designed embedded development board where the main controller transmits the values of the environmental sensing module within the embedded board to a sub-controller. The sub-controller determines the growth stage, growth height, and time and transmits its decision value to the main controller. Finally, based on the data transmitted by the sub-controller, the main controller controls the growth phase of the bio-botanic robot using a servo motor and leaf actuator. The research result not only helps children realize the variation of plant growth but also is entertainment-educational through its demonstration of the growth process of the bio-botanic robot in a short time. PMID:22247684
Planetary protection principles used for Phobos-Grunt mission
NASA Astrophysics Data System (ADS)
Martynov, M. B.; Alexashkin, S. N.; Khamidullina, N. M.; Orlov, O. I.; Novikova, N. D.; Deshevaya, E. A.; Trofimov, V. I.
2011-12-01
The article presents an analysis of the Phobos-Grunt mission, a classification of its phases in terms of planetary protection, and the main principles of activities management and definition of actions for fulfilling the planetary-protection requirements developed by Committee on Space Research.
Maintenance Decision Support System, Phase III
DOT National Transportation Integrated Search
2017-09-01
The main goal of the project was to address barriers that limit NDOTs ability to implement MDSS and MMS systems. The four project tasks included: Task 1: Develop system for tracking sand and/or deicing material usage: A system that tracks where and w...
Railroad classification yard design methodology study : East Deerfield Yard, a case study
DOT National Transportation Integrated Search
1980-02-01
This interim report documents the application of a railroad classification yard design methodology to Boston and Maine's East Deerfield Yard Rehabiliation. This case study effort represents Phase 2 of a larger effort to develop a yard design methodol...
NASA Astrophysics Data System (ADS)
Kozyra, J. U.; Liemohn, M. W.; Clauer, C. R.; Ridley, A. J.; Thomsen, M. F.; Borovsky, J. E.; Roeder, J. L.; Jordanova, V. K.; Gonzalez, W. D.
2002-08-01
The 4-6 June 1991 magnetic storm, which occurred during solar maximum conditions, is analyzed to investigate two observed features of magnetic storms that are not completely understood: (1) the mass-dependent decay of the ring current during the early recovery phase and (2) the role of preconditioning in multistep ring current development. A kinetic ring current drift-loss model, driven by dynamic fluxes at the nightside outer boundary, was used to simulate this storm interval. A strong partial ring current developed and persisted throughout the main and early recovery phases. The majority of ions in the partial ring current make one pass through the inner magnetosphere on open drift paths before encountering the dayside magnetopause. The ring current exhibited a three-phase decay in this storm. A short interval of charge-exchange loss constituted the first phase of the decay followed by a classical two-phase decay characterized by an abrupt transition between two very different decay timescales. The short interval dominated by charge-exchange loss occurred because an abrupt northward turning of the interplanetary magnetic field (IMF) trapped ring current ions on closed trajectories, and turned-off sources and ``flow-out'' losses. If this had been the end of the solar wind disturbance, decay timescales would have gradually lengthened as charge exchange preferentially removed the short-lived species; a distinctive two-phase decay would not have resulted. However, the IMF turned weakly southward, drift paths became open, and a standard two-phase decay ensued as the IMF rotated slowly northward again. As has been shown before, a two-phase decay is produced as open drift paths are converted to closed in a weakening convection electric field, driving a transition from the fast flow-out losses associated with the partial ring current to the slower charge-exchange losses associated with the trapped ring current. The open drift path geometry during the main phase and during phase 1 of the two-phase decay has important consequences for the evolution of ring current composition and for preconditioning issues. In this particular storm, ring current composition changes measured by the Combined Release and Radiation Effects Satellite (CRRES) during the main and recovery phase of the storm resulted largely from composition changes in the plasma sheet transmitted into the inner magnetosphere along open drift paths as the magnetic activity declined. Possible preconditioning elements were investigated during the multistep development of this storm, which was driven by the sequential arrival of three southward IMF Bz intervals of increasing peak strength. In each case, previous intensifications (preexisting ring currents) were swept out of the magnetosphere by the enhanced convection associated with the latest intensification and did not act as a significant preconditioning element. However, plasma sheet characteristics varied significantly between subsequent intensifications, altering the response of the magnetosphere to the sequential solar wind drivers. A denser plasma sheet (ring current source population) appeared during the second intensification, compensating for the weaker IMF Bz at this time and producing a minimum pressure-corrected Dst* value comparable to the third intensification (driven by stronger IMF Bz but a lower density plasma sheet source). The controlling influence of the plasma sheet dynamics on the ring current dynamics and its role in altering the inner magnetospheric response to solar wind drivers during magnetic storms adds a sense of urgency to understanding what processes produce time-dependent responses in the plasma sheet density, composition, and temperature.
Could aspiration of the Graafian follicle cause luteal phase deficiency?
Feichtinger, W; Kemeter, P; Szalay, S; Beck, A; Janisch, H
1982-02-01
Luteal phase quality was evaluated in 32 patients wih nonstimulated cycles after laparoscopic oocyte recovery for in vitro fertilization. A luteal phase deficiency occurred in two cases (6.2%), the mean duration of the luteal phase was 13.5 +/- 1.3 days in 30 patients, and two patients developed amenorrhea of 23 and 43 days respectively after laparoscopy in spite of normal progesterone values 7 and 9 days after oocyte recovery. Six embryo transfers were performed after fertilization and regular cleavage of the obtained oocytes. No pregnancy resulted from the embryo transfers, although the patients had apparently normal luteal phases. In one patient there was a transient beta-subunit human chorionic gonadotropin (beta-hCG) elevation in serum. Luteal phase deficiency should not be main cause of a nonsuccessful embryo transfer. However, a prophylactic luteal phase support after oocyte recovery and embryo transfer in nonstimulated cycles is proposed.
Maintenance Research. Report 6. Maintenance Training.
ERIC Educational Resources Information Center
Louisiana State Dept. of Highways, Baton Rouge.
The main objective of the training research phase of the maintenance management study was to develop and test training methods suitable for highway maintenance supervisors. Supervisors were trained by one of five different methods (lecture, group discussion, programed instruction, programed workshops, audiovisual instruction). The report documents…
[Early childhood development and risk factors in rural China: a cohort study].
Cui, Y; Gao, J Q; Yue, A; Tang, L; Luo, R F; Scott, Rozelle
2018-02-02
Objective: To investigate the development status and risk factors of infants and toddlers in rural China. Methods: In this cohort study, 603 infants (6-12 months of age, Phase Ⅰ) in the rural areas of QinLing-Bashan (Qin-Ba) in Shaanxi were recruited in the control group that received no intervention from April 2013 to October 2015. Three follow-up visits were performed every six months (Phase Ⅱ(12-18 months of age), Phase Ⅲ (18-24 months of age) and Phase Ⅳ(24-30 months of age)). In all the 4 phases (Ⅰ-Ⅳ), general data of the children and the families were collected by questionnaires, early childhood growth and development were assessed by door to door visits, children's hemoglobin levels were determined by laboratory tests, and the cognitive and motor development screening was conducted by the Bayley Scales of Infant and Toddler Development. Logistic regression was used to analyze the risk factors affecting the development of infants and toddlers in rural areas and the data were analyzed in terms of risk factors from infants, guardians and family. Results: Phase Ⅱ, Phase Ⅲ and Phase Ⅳ survey recruited 497, 483 and 486 participants respectively. The incidences of cognitive impairment (mental development scores<80) in rural areas of southern Shaanxi were 13.4% (81/603) in Phase Ⅰ(6-12 months), 20.1%(100/497) in PhaseⅡ(12-18 months), 42.9% (207/483) in Phase Ⅲ(18-24 months) and 50.4%(245/486) in Phase Ⅳ(24-30 months) respectively, which showed a significant increase with age (χ(2)=233.40, P< 0.01); the incidences of psychomotor impairment (psychomotor development scores<80) of Phase Ⅰ, Phase Ⅱ, Phase Ⅲ and Phase Ⅳ were 25.0% (151/603), 26.8% (133/497), 8.3% (40/483) and 11.9% (58/486), which showed a significant decrease with age (χ(2)=87.08, P< 0.01). Multivariate logistic regression analysis showed that the leading risk factor of the cognitive development of 24-30-month-old children was the mothers' poor education background (≤9 years of school education) ( OR= 2.56, P< 0.01), and the main risk factors affecting psychomotor development were the mothers' poor education background (≤9 years of school education) ( OR= 2.64, P< 0.05) and growth retardation ( OR= 2.95, P= 0.07). Conclusions: The early childhood development (especially cognitive development) in the rural areas of Qin-Ba in Shaanxi of China is not optimistic. More attention should be paid to the early childhood development in rural China, especially to the development of children from the mothers with poor education background.
Real-time optical signal processors employing optical feedback: amplitude and phase control.
Gallagher, N C
1976-04-01
The development of real-time coherent optical signal processors has increased the appeal of optical computing techniques in signal processing applications. A major limitation of these real-time systems is the. fact that the optical processing material is generally of a phase-only type. The result is that the spatial filters synthesized with these systems must be either phase-only filters or amplitude-only filters. The main concern of this paper is the application of optical feedback techniques to obtain simultaneous and independent amplitude and phase control of the light passing through the system. It is shown that optical feedback techniques may be employed with phase-only spatial filters to obtain this amplitude and phase control. The feedback system with phase-only filters is compared with other feedback systems that employ combinations of phase-only and amplitude-only filters; it is found that the phase-only system is substantially more flexible than the other two systems investigated.
Jin, Hongli; Liu, Yanfang; Guo, Zhimou; Wang, Jixia; Zhang, Xiuli; Wang, Chaoran; Liang, Xinmiao
2016-10-25
Traditional Chinese Medicine (TCM) is an ancient medical practice which has been used to prevent and cure diseases for thousands of years. TCMs are frequently multi-component systems with mainly unidentified constituents. The study of the chemical compositions of TCMs remains a hotspot of research. Different strategies have been developed to manage the significant complexity of TCMs, in an attempt to determine their constituents. Reversed-phase liquid chromatography (RPLC) is still the method of choice for the separation of TCMs, but has many problems related to limited selectivity. Recently, enormous efforts have been concentrated on the development of efficient liquid chromatography (LC) methods for TCMs, based on selective stationary phases. This can improve the resolution and peak capacity considerably. In addition, high-efficiency stationary phases have been applied in the analysis of TCMs since the invention of ultra high-performance liquid chromatography (UHPLC). This review describes the advances in LC methods in TCM research from 2010 to date, and focuses on novel stationary phases. Their potential in the separation of TCMs using relevant applications is also demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marsillac, Sylvain
2015-11-30
The main objective of this proposal was to use several pathways to reduce the production cost of Cu(In,Ga)Se 2 (CIGS) PV modules and therefore the levelized cost of energy (LCOE) associated with this technology. Three high cost drivers were identified, nominally: 1) Materials cost and availability; 2) Large scale uniformity; 3) Improved throughput These three cost drivers were targeted using the following pathways: 1) Reducing the thickness of the CIGS layer while enhancing materials quality; 2) Developing and applying enhanced in-situ metrology via real time spectroscopic ellipsometry; 3) Looking into alternative heterojunction partner, back contact and anti-reflection (AR) coating Elevenmore » main Tasks were then defined to achieve these goals (5 in Phase 1 and 6 in Phase 2), with 11 Milestones and 2 Go/No-go decision points at the end of Phase 1. The key results are summarized below« less
Torres-González, Ahira; López-Rivera, Paulina; Duarte-Lisci, Georgina; López-Ramírez, Ángel; Correa-Benítez, Adriana; Rivero-Cruz, J Fausto
2016-01-01
A head space solid-phase microextraction method combined with gas chromatography-mass spectrometry was developed and optimised to extract and analyse volatile compounds of Melipona beecheii geopropolis. Seventy-three constituents were identified using this technique in the sample of geopropolis collected. The main compounds detected include β-fenchene (14.53-15.45%), styrene (8.72-9.98%), benzaldehyde (7.44-7.82%) and the most relevant volatile components presents at high level in the geopropolis were terpenoids (58.17%).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1984-01-12
This report describes the work done under Phase II, the verification testing of the Kinetic Extruder. The main objective of the test program was to determine failure modes and wear rates. Only minor auxiliary equipment malfunctions were encountered. Wear rates indicate useful life expectancy of from 1 to 5 years for wear-exposed components. Recommendations are made for adapting the equipment for pilot plant and commercial applications. 3 references, 20 figures, 12 tables.
Dilution jet mixing program, phase 3
NASA Technical Reports Server (NTRS)
Srinivasan, R.; Coleman, E.; Myers, G.; White, C.
1985-01-01
The main objectives for the NASA Jet Mixing Phase 3 program were: extension of the data base on the mixing of single sided rows of jets in a confined cross flow to discrete slots, including streamlined, bluff, and angled injections; quantification of the effects of geometrical and flow parameters on penetration and mixing of multiple rows of jets into a confined flow; investigation of in-line, staggered, and dissimilar hole configurations; and development of empirical correlations for predicting temperature distributions for discrete slots and multiple rows of dilution holes.
Design, Development and Validation of the Eurostar 3000 Large Propellant Tank
NASA Astrophysics Data System (ADS)
Autric, J.-M.; Catherall, D.; Figues, C.; Brockhoff, T.; Lafranconi, R.
2004-10-01
EADS Astrium has undertaken the design and development of an enlarged propellant tank for its high modular Eurostar 3000 telecom satellites platform. The design and development activities included fracture, stress and functional analysis, the manufacturing of development models for the propellant management device, the qualification of new manufacturing processes and the optimization of the design with respect to the main requirements. The successful design and development-testing phase has allowed starting the manufacturing of the qualification model.
NASA Astrophysics Data System (ADS)
Miccio, L.; Memmolo, P.; Merola, F.; Fusco, S.; Netti, P. A.; Ferraro, P.
2014-03-01
A method for 3D tracking has been developed exploiting Digital Holography features in Microscopy (DHM). In the framework of self-consistent platform for manipulation and measurement of biological specimen we use DHM for quantitative and completely label free analysis of samples with low amplitude contrast. Tracking capability extend the potentiality of DHM allowing to monitor the motion of appropriate probes and correlate it with sample properties. Complete 3D tracking has been obtained for the probes avoiding the amplitude refocusing in traditional tracking processes. Moreover, in biology and biomedical research fields one of the main topic is the understanding of morphology and mechanics of cells and microorganisms. Biological samples present low amplitude contrast that limits the information that can be retrieved through optical bright-field microscope measurements. The main effect on light propagating in such objects is in phase. This is known as phase-retardation or phase-shift. DHM is an innovative and alternative approach in microscopy, it's a good candidate for no-invasive and complete specimen analysis because its main characteristic is the possibility to discern between intensity and phase information performing quantitative mapping of the Optical Path Length. In this paper, the flexibility of DH is employed to analyze cell mechanics of unstained cells subjected to appropriate stimuli. DHM is used to measure all the parameters useful to understand the deformations induced by external and controlled stresses on in-vitro cells. Our configuration allows 3D tracking of micro-particles and, simultaneously, furnish quantitative phase-contrast maps. Experimental results are presented and discussed for in vitro cells.
NASA Astrophysics Data System (ADS)
Choi, Ki-Seon; Moon, Il-Ju
2012-09-01
This study analyzes the characteristics of Western North Pacific (WNP) tropical cyclone (TC) activity and large-scale environments according to the Western Pacific (WP) teleconnection pattern in summer. In the positive WP phase, an anomalous cyclone and an anomalous anticyclone develop in the low and middle latitudes of the East Asia area, respectively. As a result, southeasterlies are reinforced in the northeast area of East Asia (including Korea and Japan), which facilitates the movement of TC to this area, whereas northwesterlies are reinforced in the southwest area of East Asia (including southern China and the Indochina Peninsula) which blocks the movement of TC to that area. Due to the spatial distribution of this reinforced pressure system, TCs that develop during the positive WP phase move and turn more to the northeast of the WNP than TCs which develop during the negative WP phase. The characteristics of this TC activity during the positive WP phase are associated with the upper tropospheric jet being located farther to the northeast. TCs during the negative WP phase mainly move to the west from the Philippines toward southern China and the Indochina Peninsula. Due to the terrain effect caused by the passage of TCs in mainland China, the intensity of TCs during the negative WP phase is weaker than those during the positive WP phase.
Challenges and perspective of drug repurposing strategies in early phase clinical trials.
Kato, Shumei; Moulder, Stacy L; Ueno, Naoto T; Wheler, Jennifer J; Meric-Bernstam, Funda; Kurzrock, Razelle; Janku, Filip
2015-01-01
Despite significant investments in the development of new agents only 5% of cancer drugs entering Phase I clinical trials are ultimately approved for routine clinical cancer care. Drug repurposing strategies using novel combinations of previously tested anticancer agents could reduce the cost and improve treatment outcomes. At MD Anderson Cancer Center, early phase clinical trials with drug repurposing strategies demonstrated promising outcomes in patients with both rare and common treatment refractory advanced cancers. Despite clinical efficacy advancing drug repurposing strategies in the clinical trial trajectory beyond early phase studies has been challenging mainly due to lack of funding and interest from the pharmaceutical industry. In this review, we delineate our experience and challenges with drug repurposing strategies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mekjian, Aram
2016-10-18
The main emphasis of the entire project is on issues having to do with medium energy and ultra-relativistic energy and heavy ion collisions. A major goal of both theory and experiment is to study properties of hot dense nuclear matter under various extreme conditions and to map out the phase diagram in density or chemical potential and temperature. My studies in medium energy nuclear collisions focused on the liquid-gas phase transition and cluster yields from such transitions. Here I developed both the statistical model of nuclear multi-fragmentation and also a mean field theory.
[The progress in speciation analysis of trace elements by atomic spectrometry].
Wang, Zeng-Huan; Wang, Xu-Nuo; Ke, Chang-Liang; Lin, Qin
2013-12-01
The main purpose of the present work is to review the different non-chromatographic methods for the speciation analysis of trace elements in geological, environmental, biological and medical areas. In this paper, the sample processing methods in speciation analysis were summarized, and the main strategies for non-chromatographic technique were evaluated. The basic principles of the liquid extractions proposed in the published literatures recently and their advantages and disadvantages were discussed, such as conventional solvent extraction, cloud point extraction, single droplet microextraction, and dispersive liquid-liquid microextraction. Solid phase extraction, as a non-chromatographic technique for speciation analysis, can be used in batch or in flow detection, and especially suitable for the online connection to atomic spectrometric detector. The developments and applications of sorbent materials filled in the columns of solid phase extraction were reviewed. The sorbents include chelating resins, nanometer materials, molecular and ion imprinted materials, and bio-sorbents. Other techniques, e. g. hydride generation technique and coprecipitation, were also reviewed together with their main applications.
NASA Astrophysics Data System (ADS)
Jin, Shuanggen; Jin, Rui; Kutoglu, H.
2017-06-01
The most intense geomagnetic storm in solar cycle 24 occurred on March 17, 2015, and the detailed ionospheric storm morphologies are difficultly obtained from traditional observations. In this paper, the Geostationary Earth Orbit (GEO) observations of BeiDou Navigation Satellite System (BDS) are for the first time used to investigate the ionospheric responses to the geomagnetic storm. Using BDS GEO and GIMs TEC series, negative and positive responses to the March 2015 storm are found at local and global scales. During the main phase, positive ionospheric storm is the main response to the geomagnetic storm, while in the recovery phase, negative phases are pronounced at all latitudes. Maximum amplitudes of negative and positive phases appear in the afternoon and post-dusk sectors during both main and recovery phases. Furthermore, dual-peak positive phases in main phase and repeated negative phase during the recovery are found from BDS GEO observations. The geomagnetic latitudes corresponding to the maximum disturbances during the main and recovery phases show large differences, but they are quasi-symmetrical between southern and northern hemispheres. No clear zonal propagation of traveling ionospheric disturbances is detected in the GNSS TEC disturbances at high and low latitudes. The thermospheric composition variations could be the dominant source of the observed ionospheric storm effect from GUVI [O]/[N2] ratio data as well as storm-time electric fields. Our study demonstrates that the BDS (especially the GEO) observations are an important data source to observe ionospheric responses to the geomagnetic storm.
Schoorel, E N C; Vankan, E; Scheepers, H C J; Augustijn, B C C; Dirksen, C D; de Koning, M; van Kuijk, S M J; Kwee, A; Melman, S; Nijhuis, J G; Aardenburg, R; de Boer, K; Hasaart, T H M; Mol, B W J; Nieuwenhuijze, M; van Pampus, M G; van Roosmalen, J; Roumen, F J M E; de Vries, R; Wouters, M G A J; van der Weijden, T; Hermens, R P M G
2014-01-01
To develop a patient decision aid (PtDA) for mode of delivery after caesarean section that integrates personalised prediction of vaginal birth after caesarean (VBAC) with the elicitation of patient preferences and evidence-based information. A PtDA was developed and pilot tested using the International Patients Decision Aid Standards (IPDAS) criteria. Obstetric health care in the Netherlands. A multidisciplinary steering group, an expert panel, and 25 future users of the PtDA, i.e. women with a previous caesarean section. The development consisted of a construction phase (definition of scope and purpose, and selection of content, framework, and format) and a pilot testing phase by interview. The process was supervised by a multidisciplinary steering group. Usability, clarity, and relevance. The construction phase resulted in a booklet including unbiased balanced information on mode of birth after caesarean section, a preference elicitation exercise, and tailored risk information, including a prediction model for successful VBAC. During pilot testing, visualisation of risks and clarity formed the main basis for revisions. Pilot testing showed the availability of tailored structured information to be the main factor involving women in decision-making. The PtDA meets 39 out of 50 IPDAS criteria (78%): 23 out of 23 criteria for content (100%) and 16 out of 20 criteria for the development process (80%). Criteria for effectiveness (n = 7) were not evaluated. An evidence-based PtDA was developed, with the probability of successful VBAC and the availability of structured information as key items. It is likely that the PtDA enhances the quality of decision-making on mode of birth after caesarean section. © 2013 Royal College of Obstetricians and Gynaecologists.
ERIC Educational Resources Information Center
KAYA, ESIN; AND OTHERS
A TWO-YEAR COOPERATIVE RESEARCH PROJECT (1965-1967) WAS CONDUCTED TO SYNTHESIZE THE BODY OF AVAILABLE EMPIRICAL KNOWLEDGE RELATED TO EDUCATIONAL PRACTICE IN A MANNER TYPICAL OF SCIENTIFIC THEORY CONSTRUCTION AND TO DEVELOP A DICTIONARY OF OVER 600 COMMON EDUCATIONAL TERMS OPERATIONALLY DEFINED IN AN APPENDED GLOSSARY. THE THREE MAIN PHASES OF THE…
Designing a model for trauma system management using public health approach: the case of Iran.
Tarighi, Payam; Tabibi, Seyed Jamaledin; Motevalian, Seyed Abbas; Tofighi, Shahram; Maleki, Mohammad Reza; Delgoshaei, Bahram; Panahi, Farzad; Masoomi, Gholam Reza
2012-01-01
Trauma is a leading cause of death and disability around the world. Injuries are responsible for about six million deaths annually, of which ninety percent occur in developing countries. In Iran, injuries are the most common cause of death among age groups below fifty. Trauma system development is a systematic and comprehensive approach to injury prevention and treatment whose effectiveness has been proved. The present study aims at designing a trauma system management model as the first step toward trauma system establishment in Iran. In this qualitative research, a conceptual framework was developed based on the public health approach and three well-known trauma system models. We used Benchmarks, Indicators and Scoring (BIS) to analyze the current situation of Iran trauma care system. Then the trauma system management was designed using the policy development phase of public health approach The trauma system management model, validated by a panel of experts, describes lead agency, trauma system plan, policy-making councils, and data-based control according to the four main functions of management: leading, planning, organizing and controlling. This model may be implemented in two phases: the exclusive phase, focusing on resource integration and the inclusive phase, which concentrates on system development. The model could facilitate the development of trauma system in Iran through pilot studies as the assurance phase of public health approach. Furthermore, the model can provide a practical framework for trauma system management at the international level.
Cheng, Shunfan; Wang, Yanjie; Zhuang, Libin; Xue, Jian; Wei, Yanying; Feldhoff, Armin; Caro, Jürgen; Wang, Haihui
2016-08-26
A novel concept for the preparation of multiphase composite ceramics based on demixing of a single ceramic precursor has been developed and used for the synthesis of a dual-phase H2 -permeable ceramic membrane. The precursor BaCe0.5 Fe0.5 O3-δ decomposes on calcination at 1370 °C for 10 h into two thermodynamically stable oxides with perovskite structures: the cerium-rich oxide BaCe0.85 Fe0.15 O3-δ (BCF8515) and the iron-rich oxide BaCe0.15 Fe0.85 O3-δ (BCF1585), 50 mol % each. In the resulting dual-phase material, the orthorhombic perovskite BCF8515 acts as the main proton conductor and the cubic perovskite BCF1585 as the main electron conductor. The dual-phase membrane shows an extremely high H2 permeation flux of 0.76 mL min(-1) cm(-2) at 950 °C with 1.0 mm thickness. This auto-demixing concept should be applicable to the synthesis of other ionic-electronic conducting ceramics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Arredondo, Armando; Orozco, Emanuel; De Icaza, Esteban
2005-01-01
The main objective was to identify trends and evidence on health financing after health care decentralization. Evaluative research with a before-after design integrating qualitative and quantitative analysis. Taking into account feasibility, political and technical criteria, three Latin American countries were selected as study populations: Mexico, Nicaragua and Peru. The methodology had two main phases. In the first phase, the study referred to secondary sources of data and documents to obtain information about the following variables: type of decentralization implemented, source of finance, funds of financing, providers, final use of resources and mechanisms for resource allocation. In the second phase, the study referred to primary data collected in a survey of key personnel from the health sectors of each country. The trends and evidence reported in all five financing indicators may identify major weaknesses and strengths in health financing. Weaknesses: a lack of human resources trained in health economics who can implement changes, a lack of financial resource independence between the local and central levels, the negative behavior of the main macro-economic variables, and the difficulty in developing new financing alternatives. Strengths: the sharing between the central level and local levels of responsibility for financing health services, the implementation of new organizational structures for the follow-up of financial changes at the local level, the development and implementation of new financial allocation mechanisms taking as a basis the efficiency and equity principles, new technique of a per-capita adjustment factor corrected at the local health needs, and the increase of financing contributions from households and local levels of government.
Bhaskar, Vaishnavi; Chan, Hsun-Liang; MacEachern, Mark; Kripfgans, Oliver D
2018-05-23
Ultrasonography has shown promising diagnostic value in dental implant imaging research; however, exactly how ultrasound was used and at what stage of implant therapy it can be applied has not been systematically evaluated. Therefore, the aim of this review is to investigate potential indications of ultrasound use in the three implant treatment phases, namely planning, intraoperative and postoperative phase. Eligible manuscripts were searched in major databases with a combination of key words related to the use of ultrasound imaging in implant therapy. An initial search yielded 414 articles, after further review, 28 articles were finally included for this systematic review. Ultrasound was found valuable, though at various development stages, for evaluating (1) soft tissues, (2) hard tissues (3) vital structures and (4) implant stability. B-mode, the main function to image anatomical structures of interest, has been evaluated in pre-clinical and clinical studies. Quantitative ultrasound parameters, e.g. sound speed and amplitude, are being developed to evaluate implant-bone stability, mainly in simulation and pre-clinical studies. Ultrasound could be potentially useful in all 3 treatment phases. In the planning phase, ultrasound could evaluate vital structures, tissue biotype, ridge width/density, and cortical bone thickness. During surgery, it can provide feedback by identifying vital structures and bone boundary. At follow-up visits, it could evaluate marginal bone level and implant stability. Understanding the current status of ultrasound imaging research for implant therapy would be extremely beneficial for accelerating translational research and its use in dental clinics.
DOT National Transportation Integrated Search
2008-03-01
The main objective of this study was to determine the most beneficial and cost-effective accelerated load facility that can be used in conjunction with LTRCs Accelerated Load Facility (ALF). The facility will be used primarily for conducting preli...
Theoretical Bases for Using Virtual Reality in Education
ERIC Educational Resources Information Center
Chen, Chwen Jen
2009-01-01
This article elaborates on how the technical capabilities of virtual reality support the constructivist learning principles. It introduces VRID, a model for instructional design and development that offers explicit guidance on how to produce an educational virtual environment. The define phase of VRID consists of three main tasks: forming a…
USDA-ARS?s Scientific Manuscript database
Mammary stem cells (MaSC) are essential for growth and maintenance of the mammary epithelium. Two main phases of mammary growth include ductal elongation prior to puberty and lobulo-alveolar growth and development during pregnancy. Some studies have utilized morphological characteristics and retenti...
Quantification of tylosin and tylosin antibiotic resistance genes in cattle waste
USDA-ARS?s Scientific Manuscript database
Presented is the development of a solid phase extraction (SPE) procedure and a liquid chromatography-mass spectrometry (LC-MS/MS) method for quantifying tylosin in cattle waste samples. Tylosin is a macrolide antibiotic found naturally as a fermentation product of Streptomyces fradiae and is mainly ...
Debrus, Benjamin; Guillarme, Davy; Rudaz, Serge
2013-10-01
A complete strategy dedicated to quality-by-design (QbD) compliant method development using design of experiments (DOE), multiple linear regressions responses modelling and Monte Carlo simulations for error propagation was evaluated for liquid chromatography (LC). The proposed approach includes four main steps: (i) the initial screening of column chemistry, mobile phase pH and organic modifier, (ii) the selectivity optimization through changes in gradient time and mobile phase temperature, (iii) the adaptation of column geometry to reach sufficient resolution, and (iv) the robust resolution optimization and identification of the method design space. This procedure was employed to obtain a complex chromatographic separation of 15 antipsychotic basic drugs, widely prescribed. To fully automate and expedite the QbD method development procedure, short columns packed with sub-2 μm particles were employed, together with a UHPLC system possessing columns and solvents selection valves. Through this example, the possibilities of the proposed QbD method development workflow were exposed and the different steps of the automated strategy were critically discussed. A baseline separation of the mixture of antipsychotic drugs was achieved with an analysis time of less than 15 min and the robustness of the method was demonstrated simultaneously with the method development phase. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Han, Bing; Tao, Wang; Chen, Yanbin; Li, Hao
2017-08-01
In the current work, T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys for aircraft fuselage panels have been fabricated by double-sided fiber laser beam welding with different filler wires. A new type wire CW3 (Al-6.2Cu-5.4Si) was studied and compared with conventional wire AA4047 (Al-12Si) mainly on microstructure and mechanical properties. It was found that the main combined function of Al-6.2%Cu-5.4%Si in CW3 resulted in considerable improvements especially on intergranular strength, hot cracking susceptibility and hoop tensile properties. Typical non-dendritic equiaxed zone (EQZ) was observed along welds' fusion boundary. Hot cracks and fractures during the load were always located within the EQZ, however, this typical zone could be restrained by CW3, effectively. Furthermore, changing of the main intergranular precipitated phase within the EQZ from T phase by AA4047 to T2 phase by CW3 also resulted in developments on microscopic intergranular reinforcement and macroscopic hoop tensile properties. In addition, bridging caused by richer substructure dendrites within CW3 weld's columnar zone resulted in much lower hot cracking susceptibility of the whole weld than AA4047.
Dose escalation methods in phase I cancer clinical trials.
Le Tourneau, Christophe; Lee, J Jack; Siu, Lillian L
2009-05-20
Phase I clinical trials are an essential step in the development of anticancer drugs. The main goal of these studies is to establish the recommended dose and/or schedule of new drugs or drug combinations for phase II trials. The guiding principle for dose escalation in phase I trials is to avoid exposing too many patients to subtherapeutic doses while preserving safety and maintaining rapid accrual. Here we review dose escalation methods for phase I trials, including the rule-based and model-based dose escalation methods that have been developed to evaluate new anticancer agents. Toxicity has traditionally been the primary endpoint for phase I trials involving cytotoxic agents. However, with the emergence of molecularly targeted anticancer agents, potential alternative endpoints to delineate optimal biological activity, such as plasma drug concentration and target inhibition in tumor or surrogate tissues, have been proposed along with new trial designs. We also describe specific methods for drug combinations as well as methods that use a time-to-event endpoint or both toxicity and efficacy as endpoints. Finally, we present the advantages and drawbacks of the various dose escalation methods and discuss specific applications of the methods in developmental oncotherapeutics.
NASA Astrophysics Data System (ADS)
Lanuru, Mahatma; Mashoreng, S.; Amri, K.
2018-03-01
The success of seagrass transplantation is very much depending on the site selection and suitable transplantation methods. The main objective of this study is to develop and use a site-selection model to identify the suitability of sites for seagrass (Enhalus acoroides) transplantation. Model development was based on the physical and biological characteristics of the transplantation site. The site-selection process is divided into 3 phases: Phase I identifies potential seagrass habitat using available knowledge, removes unnecessary sites before the transplantation test is performed. Phase II involves field assessment and transplantation test of the best scoring areas identified in Phase I. Phase III is the final calculation of the TSI (Transplant Suitability Index), based on results from Phases I and II. The model was used to identify the suitability of sites for seagrass transplantation in the West coast of South Sulawesi (3 sites at Labakkang Coast, 3 sites at Awerange Bay, and 3 sites at Lale-Lae Island). Of the 9 sites, two sites were predicted by the site-selection model to be the most suitable sites for seagrass transplantation: Site II at Labakkang Coast and Site III at Lale-Lae Island.
Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program
NASA Technical Reports Server (NTRS)
Edwards, Bryan; Cox, Charles; Booth, Earl R., Jr. (Technical Monitor)
2002-01-01
As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.
Yu Pomjakushin, V; Krzton-Maziopa, A; Pomjakushina, E V; Conder, K; Chernyshov, D; Svitlyk, V; Bosak, A
2012-10-31
The crystal and magnetic structures of the superconducting iron-based chalcogenides Rb(y)Fe(2-x)Se(2) have been studied by means of single-crystal synchrotron x-ray and high-resolution neutron powder diffraction in the temperature range 2-570 K. The ground state of the crystal is an intrinsically phase-separated state with two distinct-by-symmetry phases. The main phase has the iron vacancy ordered √5 × √5 superstructure (I4/m space group) with AFM ordered Fe spins. The minority phase does not have √5 × √5-type of ordering and has a smaller in-plane lattice constant a and larger tetragonal c-axis and can be well described by assuming the parent average vacancy disordered structure (I4/mmm space group) with the refined stoichiometry Rb(0.60(5))(Fe(1.10(5))Se)(2). The minority phase amounts to 8-10% mass fraction. The unit cell volume of the minority phase is 3.2% smaller than the one of the main phase at T = 2 K and has quite different temperature dependence. The minority phase merges with the main vacancy ordered phase on heating above the phase separation temperature T(P) = 475 K. The spatial dimensions of the phase domains strongly increase above T(P) from 1000 to >2500 Å due to the integration of the regions of the main phase that were separated by the second phase at low temperatures. Additional annealing of the crystals at a temperature T = 488 K, close to T(P), for a long time drastically reduces the amount of the minority phase.
Novel drugs in clinical development for hepatocellular carcinoma.
Waidmann, Oliver; Trojan, Jörg
2015-01-01
Sorafenib is the only systemic drug approved for the treatment of advanced hepatocellular carcinoma (HCC). Within recent years, several investigational agents mainly targeting angiogenesis failed in late-phase clinical development either due to toxicity or lack of benefit. This review covers recent clinical data on systemic agents and ongoing trials in patients with advanced HCC. In unselected patients with advanced HCC, disappointing results have been reported from several large trials. However, in two subgroups encouraging results have been achieved. Treatment with the MET inhibitor tivantinib resulted in a substantial survival benefit in the subgroup of MET overexpressing tumors in a randomized Phase II trial. Furthermore, the vascular endothelial growth factor receptor 2 antibody ramucirumab resulted in improved overall survival in patients with baseline α-fetoprotein (AFP) ≥ 400 ng/ml in a Phase III trial. These two agents, and several others, will be further developed in HCC. Moreover, immunotherapeutics such as checkpoint inhibitors, programmed death receptor-1 blocking antibodies and oncolytic viruses are under investigation in advanced HCC.
Design of automatic rotor blades folding system using NiTi shape memory alloy actuator
NASA Astrophysics Data System (ADS)
Ali, M. I. F.; Abdullah, E. J.
2016-10-01
This present paper will study the requirements for development of a new Automatic Rotor Blades Folding (ARBF) system that could possibly solve the availability, compatibility and complexity issue of upgrading a manual to a fully automatic rotor blades folding system of a helicopter. As a subject matter, the Royal Malaysian Navy Super Lynx Mk 100 was chosen as the baseline model. The aim of the study was to propose a design of SMART ARBF's Shape Memory Alloy (SMA) actuator and proof of operating concept using a developed scale down prototype model. The performance target for the full folding sequence is less than ten minutes. Further analysis on design requirements was carried out, which consisted of three main phases. Phase 1 was studying the SMA behavior on the Nickel Titanium (NiTi) SMA wire and spring (extension type). Technical values like activation requirement, contraction length, and stroke- power and stroke-temperature relationship were gathered. Phase 2 was the development of the prototype where the proposed design of stepped-retractable SMA actuator was introduced. A complete model of the SMART ARBF system that consisted of a base, a main rotor hub, four main rotor blades, four SMA actuators and also electrical wiring connections was fabricated and assembled. Phase 3 was test and analysis whereby a PINENG-PN968s-10000mAh Power Bank's 5 volts, which was reduced to 2.5 volts using LM2596 Step-Down Converter, powered and activated the NiTi spring inside each actuator. The bias spring (compression type), which functions to protract and push the blades to spread position, will compress together with the retraction of actuators and pull the blades to the folding position. Once the power was removed and SMA spring deactivated, the bias spring stiffness will extend the SMA spring and casing and push the blades back to spread position. The timing for the whole revolution was recorded. Based on the experimental analysis, the recorded timing for folding sequence is 2.5 minutes in average and therefore met the required criteria.
Chemical enhanced oil recovery (EOR) activities in Indonesia: How it's future
NASA Astrophysics Data System (ADS)
Abdurrahman, Muslim
2017-05-01
Enhanced oil recovery (EOR) is a proven method for increasing oil production in many oil fields in the world. Huge oil remaining in the reservoir after primary and secondary recovery stage are the main reason for developing EOR methods. Approximately of 49.50 billion barrels oil as a candidate for EOR activities in Indonesia. This present study focuses on the chemical EOR activities involved surfactant and polymer. This research based on pertinent information from various resources such as journal papers, conference papers, and report from the government. Based on this information, this paper explain in detail the progress of each project and it shows the potential oil field employ chemical EOR in the near future. Generally, the EOR activities can be categorized into two phases such as preliminary study phase and field implementation phase. In the preliminary study, the activities simply involve experimental and/or simulation works. Following the preliminary is the field implementation phase which can be categorized into three phases such as field trial, pilot project, and full-scale. In fact, several activities have been conducted by Lemigas (government oil and gas research center), Institut Teknologi Bandung, Institut Pertanian Bogor. These activities focused on laboratory and simulation work. Those institutions have been developing the chemical formula collaborating with oil companies for applying the EOR method in their oil fields. Currently, status of chemical EOR activities include 5 oil fields under pilot project and 12 oil fields under field trial. There are 7 oil fields applying surfactant, 4 oil fields by alkaline-surfactant-polymer (ASP), 2 oil fields by polymer, 1 oil field by surfactant polymer (SP), and 1 oil field by caustic. According to this information, we will have insight knowledge about the EOR current activities, the main issues, future activities on chemical EOR in Indonesia. Moreover, this study can became the preliminary information for researchers who interested conducting further research and development on the chemical EOR activities in the near future.
Clinical pharmacology of novel anti-Alzheimer disease modifying medications.
Caraci, Filippo; Bosco, Paolo; Leggio, Gian Marco; Malaguarnera, Michele; Drago, Filippo; Bucolo, Claudio; Salomone, Salvatore
2013-01-01
In recent years, efforts have been directed to develop "disease-modifying" medications to treat Alzheimer's disease (AD), able to halt or slow the pathological process. Because the earlier the treatment starts, the greater is the possibility of efficacy, it is important to set up biomarkers for early diagnosis of functional brain abnormalities, before the clinical manifestation of the overt disease. Up to now, strategies to develop disease-modifying drugs have mainly targeted β amyloid (Aβ, accumulation, aggregation, clearance) and/or tau protein (phosphorylation and aggregation). Active and passive immunotherapy is the main strategy aimed at increasing Aβ clearance. Unfortunately several candidate diseasemodifying drugs have failed in phase III clinical trials conducted in mild to moderate AD. More recently, in phase III studies, bapineuzumab has been discontinued because it did not prove clinically effective (despite its significant effect on biomarkers), while solaneuzumab has been found effective in slowing AD progression. Several methological problems have been recently pointed out to explain the lack of clinical efficacy of novel disease-modifying drug-treatments; moreover, new insights in pathophysiology of AD give the premise to develop novel drug targeting. Clinical trials recently completed and/or still ongoing are discussed in the present review.
NASA Astrophysics Data System (ADS)
Schmutzer, G.; Avram, V.; Feher, I.; David, L.; Moldovan, Z.
2012-02-01
The volatile composition of alcoholic beverage was studied by headspace solid-phase microextraction (HSSPME) method and gas chromatography - mass spectrometry (GC-MS). Some volatile compounds, such as alcohols, esters, terpenes and other are mainly responsible for the flavor of fortified wines and their amounts specify the quality of the alcoholic beverages. From this perspective it is interesting to develop a rapid, selective and sensitive analytical method suitable for simultaneous quantification of the main molecules being responsible for the organoleptic characteristic of alcoholic beverages. Vermouth fortified drink was analyzed in order to characterize the volatile profile. Using the HS-SPME/GC-MS a number of twenty-six volatile compounds from a commercial market alcoholic beverage were identified. The most abundant compounds were m-thymol, o-thymol and eugenol, alongside of the ethyl ester compounds.
Klein, Thomas; Clemens, Helmut; Mayer, Svea
2016-01-01
Advanced intermetallic alloys based on the γ-TiAl phase have become widely regarded as most promising candidates to replace heavier Ni-base superalloys as materials for high-temperature structural components, due to their facilitating properties of high creep and oxidation resistance in combination with a low density. Particularly, recently developed alloying concepts based on a β-solidification pathway, such as the so-called TNM alloy, which are already incorporated in aircraft engines, have emerged offering the advantage of being processible using near-conventional methods and the option to attain balanced mechanical properties via subsequent heat-treatment. Development trends for the improvement of alloying concepts, especially dealing with issues regarding alloying element distribution, nano-scale phase characterization, phase stability, and phase formation mechanisms demand the utilization of high-resolution techniques, mainly due to the multi-phase nature of advanced TiAl alloys. Atom probe tomography (APT) offers unique possibilities of characterizing chemical compositions with a high spatial resolution and has, therefore, been widely used in recent years with the aim of understanding the materials constitution and appearing basic phenomena on the atomic scale and applying these findings to alloy development. This review, thus, aims at summarizing scientific works regarding the application of atom probe tomography towards the understanding and further development of intermetallic TiAl alloys. PMID:28773880
Klein, Thomas; Clemens, Helmut; Mayer, Svea
2016-09-06
Advanced intermetallic alloys based on the γ-TiAl phase have become widely regarded as most promising candidates to replace heavier Ni-base superalloys as materials for high-temperature structural components, due to their facilitating properties of high creep and oxidation resistance in combination with a low density. Particularly, recently developed alloying concepts based on a β-solidification pathway, such as the so-called TNM alloy, which are already incorporated in aircraft engines, have emerged offering the advantage of being processible using near-conventional methods and the option to attain balanced mechanical properties via subsequent heat-treatment. Development trends for the improvement of alloying concepts, especially dealing with issues regarding alloying element distribution, nano-scale phase characterization, phase stability, and phase formation mechanisms demand the utilization of high-resolution techniques, mainly due to the multi-phase nature of advanced TiAl alloys. Atom probe tomography (APT) offers unique possibilities of characterizing chemical compositions with a high spatial resolution and has, therefore, been widely used in recent years with the aim of understanding the materials constitution and appearing basic phenomena on the atomic scale and applying these findings to alloy development. This review, thus, aims at summarizing scientific works regarding the application of atom probe tomography towards the understanding and further development of intermetallic TiAl alloys.
A statistical analysis of substorm associated tail activity
NASA Astrophysics Data System (ADS)
Hsu, Tung-Shin; McPherron, Robert L.
2012-11-01
Substorm onset timing is a critical issue in magnetotail dynamics research. Solar wind energy is accumulated in the magnetosphere and the configuration of the magnetosphere evolves toward an unstable state during the growth phase. At some point, the expansion phase begins and the stored energy is released through a variety of processes that return the magnetosphere to a lower energy state. In recovery the various processes die away. Unfortunately, the ground and magnetospheric signatures of onset, i.e. energy release, can be seen both in the growth phase prior to onset and in the expansion phase after onset. Some investigators refer to each of these events as a substorm. Tail observations suggest that most substorms have one event that differentiates the behavior of the tail field and plasma. We refer to this time as the "main substorm onset". Each substorm associated phenomenon is timed independently and then compared with main substorm onsets. ISEE-2 tail observations are used to examine the tail lobe magnetic conditions associated with substorms because ISEE-2 orbit has a high inclination and frequently observes lobe field. Approximately 70 ˜ 75% of tail lobe Bt and Bz change are associated with the main substorm onset. If the satellite is more than 3 Re above (below) the neutral sheet, 86% (57%) of plasma pressure dropouts are associated with substorms. We interpret our results as evidence that the effect of the growth phase is to drive the magnetosphere towards instability. As it approaches global instability local regions become temporarily unstable but are rapidly quenched. Eventually one of these events develops into the global instability that releases most of the stored energy and returns the magnetosphere to a more stable configuration.
[Research on Shielding of Emboli with the Phase-Controlled Ultrasound].
Liu, Chuang; Bai, Jingfeng
2016-01-01
The postoperative neurological complications is associated with intraoperative cerebral emboli, which results from extracorporeal circulation and operation. It can effectively reduce the incidence of neurological complications with ultrasonic radiation. In fluids, a particle will change it's motion trail when it is acted by the radiation force generated by the ultrasound. This article mainly discuss how to shielding emboli with ultrasound. The equipment can transmit phased ultrasonic signals, which is designed on a FPGA development board. The board can generate a square wave, which is converted into a sine wave through a power amplifier. In addition, the control software has been developed on Qt development environment. The result indicates it's feasible to shielding emboli with ultrasonic radiation force. This article builds a strong foundation for the future research.
NASA Technical Reports Server (NTRS)
Feigenbaum, H.; Kaufman, A.; Wang, C. L.; Werth, J.; Whelan, J. A.
1983-01-01
Operating experience with a 5kW methanol-air integrated system is described. On-going test results for a 24-cell, two-sq ft (4kW) stack are reported. The main activity for this stack is currently the evaluation of developmental non-metalic cooling plates. Single-cell test results are presented for a promising developmental cathode catalyst.
Quantum model for electro-optical amplitude modulation.
Capmany, José; Fernández-Pousa, Carlos R
2010-11-22
We present a quantum model for electro-optic amplitude modulation, which is built upon quantum models of the main photonic components that constitute the modulator, that is, the guided-wave beamsplitter and the electro-optic phase modulator and accounts for all the different available modulator structures. General models are developed both for single and dual drive configurations and specific results are obtained for the most common configurations currently employed. Finally, the operation with two-photon input for the control of phase-modulated photons and the important topic of multicarrier modulation are also addressed.
Flow induced vibrations in the SSME injector heads
NASA Technical Reports Server (NTRS)
Lepore, Frank A.
1991-01-01
A description is given of the flowfield in the Space Shuttle Main Engine (SSME) powerhead, the mechanisms which control flow-induced vibrations, and previous experimental work. An in-depth description is given of the development phase of the program , which includes the analysis, design, and fabrication of liquid oxygen (LOX) posts models used in the experimental phase, as well as test facilities, equipment, and procedures used. Also covered is the experimental data analysis, which includes overall steady state powerhead flowfield as well as the high frequency response of the LOX posts.
Defect-Induced Hedgehog Polarization States in Multiferroics
NASA Astrophysics Data System (ADS)
Li, Linze; Cheng, Xiaoxing; Jokisaari, Jacob R.; Gao, Peng; Britson, Jason; Adamo, Carolina; Heikes, Colin; Schlom, Darrell G.; Chen, Long-Qing; Pan, Xiaoqing
2018-03-01
Continuous developments in nanotechnology require new approaches to materials synthesis that can produce novel functional structures. Here, we show that nanoscale defects, such as nonstoichiometric nanoregions (NSNRs), can act as nano-building blocks for creating complex electrical polarization structures in the prototypical multiferroic BiFeO3 . An array of charged NSNRs are produced in BiFeO3 thin films by tuning the substrate temperature during film growth. Atomic-scale scanning transmission electron microscopy imaging reveals exotic polarization rotation patterns around these NSNRs. These polarization patterns resemble hedgehog or vortex topologies and can cause local changes in lattice symmetries leading to mixed-phase structures resembling the morphotropic phase boundary with high piezoelectricity. Phase-field simulations indicate that the observed polarization configurations are mainly induced by charged states at the NSNRs. Engineering defects thus may provide a new route for developing ferroelectric- or multiferroic-based nanodevices.
Defect-Induced Hedgehog Polarization States in Multiferroics.
Li, Linze; Cheng, Xiaoxing; Jokisaari, Jacob R; Gao, Peng; Britson, Jason; Adamo, Carolina; Heikes, Colin; Schlom, Darrell G; Chen, Long-Qing; Pan, Xiaoqing
2018-03-30
Continuous developments in nanotechnology require new approaches to materials synthesis that can produce novel functional structures. Here, we show that nanoscale defects, such as nonstoichiometric nanoregions (NSNRs), can act as nano-building blocks for creating complex electrical polarization structures in the prototypical multiferroic BiFeO_{3}. An array of charged NSNRs are produced in BiFeO_{3} thin films by tuning the substrate temperature during film growth. Atomic-scale scanning transmission electron microscopy imaging reveals exotic polarization rotation patterns around these NSNRs. These polarization patterns resemble hedgehog or vortex topologies and can cause local changes in lattice symmetries leading to mixed-phase structures resembling the morphotropic phase boundary with high piezoelectricity. Phase-field simulations indicate that the observed polarization configurations are mainly induced by charged states at the NSNRs. Engineering defects thus may provide a new route for developing ferroelectric- or multiferroic-based nanodevices.
Main braking phase for a soft moon landing as a form of trajectory correction
NASA Astrophysics Data System (ADS)
Likhachev, V. N.; Sikharulidze, Yu. G.; Fedotov, V. P.
2013-12-01
Rationale is given for the braking profile of a spacecraft making a soft landing on the Moon's surface, including the following four phases: main braking, free fall, repeated braking, and descent at a constant speed. Due to the large altitude differential over the braking path in near-polar regions of the Moon, main braking is proposed as a type of trajectory correction impulse using no altimeter. The boundary problem solution and statistical calculations are used to give the potential energy costs and characteristics of the dispersion characteristics for this phase and choose an optimal thrust-to-weight ratio for the phase.
High resolution kilometric range optical telemetry in air by radio frequency phase measurement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guillory, Joffray; García-Márquez, Jorge; Truong, Daniel
2016-07-15
We have developed an optical Absolute Distance Meter (ADM) based on the measurement of the phase accumulated by a Radio Frequency wave during its propagation in the air by a laser beam. In this article, the ADM principle will be described and the main results will be presented. In particular, we will emphasize how the choice of an appropriate photodetector can significantly improve the telemeter performances by minimizing the amplitude to phase conversion. Our prototype, tested in the field, has proven its efficiency with a resolution better than 15 μm for a measurement time of 10 ms and distances upmore » to 1.2 km.« less
Coupled Structural, Thermal, Phase-change and Electromagnetic Analysis for Superconductors, Volume 2
NASA Technical Reports Server (NTRS)
Felippa, C. A.; Farhat, C.; Park, K. C.; Militello, C.; Schuler, J. J.
1996-01-01
Described are the theoretical development and computer implementation of reliable and efficient methods for the analysis of coupled mechanical problems that involve the interaction of mechanical, thermal, phase-change and electromag subproblems. The focus application has been the modeling of superconductivity and associated quantum-state phase change phenomena. In support of this objective the work has addressed the following issues: (1) development of variational principles for finite elements, (2) finite element modeling of the electromagnetic problem, (3) coupling of thermel and mechanical effects, and (4) computer implementation and solution of the superconductivity transition problem. The main accomplishments have been: (1) the development of the theory of parametrized and gauged variational principles, (2) the application of those principled to the construction of electromagnetic, thermal and mechanical finite elements, and (3) the coupling of electromagnetic finite elements with thermal and superconducting effects, and (4) the first detailed finite element simulations of bulk superconductors, in particular the Meissner effect and the nature of the normal conducting boundary layer. The theoretical development is described in two volumes. Volume 1 describes mostly formulation specific problems. Volume 2 describes generalization of those formulations.
NASA Astrophysics Data System (ADS)
Shi, Xiaoning; Zhu, Minggang; Zhou, Dong; Song, Liwei; Guo, Zhaohui; Li, Jia; Li, Wei
2018-05-01
The sintered (Ce, Nd)-Fe-B magnets were produced widely by Double Main Phase (DMP) method in China as the magnetic properties of the DMP magnets are superior to those of single main phase (SMP) magnets with the same nominal composition. In this work, the microstructure and corrosion mechanism of the sintered (Ce0.2Nd0.8)30FebalB (wt.%) magnets prepared by DMP and SMP method were studied in detail. Compared to SMP magnets, the DMP magnets have more positive corrosion potential, lower corrosion current density, larger electron transfer resistance, and lower mass loss of the free corrosion experiment in 0.5mol/l Na2SO4 aqueous solution. All of the results show that the DMP magnets have better corrosion resistance than SMP magnets. The back scattered electron images show that the crystalline grains of the DMP magnets are sphericity with a smooth surface while the SMP ones have plenty of edges and corners. Besides, the distribution of Ce/Nd is much more uneven in both magnetic phase and rare earth (Re)-rich phase of the DMP magnets than those of SMP magnets. After corrosion, DMP magnets show eroded magnetic phase and intact Re-rich phase, which indicate that galvanic corrosion of the Re-rich phase acting as the cathode appears.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pendse, Hemant P.
Maine and its industries identified more efficient utilization of biomass as a critical economic development issue. In Phase I of this implementation project, a research team was assembled, research equipment was implemented and expertise was demonstrated in pyrolysis, hydrodeoxygenation of pyrolysis oils, catalyst synthesis and characterization, and reaction engineering. Phase II built upon the infrastructure to innovate reaction pathways and process engineering, and integrate new approaches for fuels and chemical production within pulp and paper and other industries within the state. This research cluster brought together chemists, engineers, physicists and students from the University of Maine, Bates College, and Bowdoinmore » College. The project developed collaborations with Oak Ridge National Laboratory and Brookhaven National Laboratory. The specific research projects within this proposal were of critical interest to the DoE - in particular the biomass program within EERE and the catalysis/chemical transformations program within BES. Scientific and Technical Merit highlights of this project included: (1) synthesis and physical characterization of novel size-selective catalyst/supports using engineered mesoporous (1-10 nm diameter pores) materials, (2) advances in fundamental knowledge of novel support/ metal catalyst systems tailored for pyrolysis oil upgrading, (3) a microcalorimetric sensing technique, (4) improved methods for pyrolysis oil characterization, (5) production and characterization of woody biomass-derived pyrolysis oils, (6) development of two new patented bio oil pathways: thermal deoxygenation (TDO) and formate assisted pyrolysis (FASP), and (7) technoeconomics of pyrolysis of Maine forest biomass. This research cluster has provided fundamental knowledge to enable and assess pathways to thermally convert biomass to hydrocarbon fuels and chemicals.« less
A Chain of Modeling Tools For Gas and Aqueous Phase Chemstry
NASA Astrophysics Data System (ADS)
Audiffren, N.; Djouad, R.; Sportisse, B.
Atmospheric chemistry is characterized by the use of large set of chemical species and reactions. Handling with the set of data required for the definition of the model is a quite difficult task. We prsent in this short article a preprocessor for diphasic models (gas phase and aqueous phase in cloud droplets) named SPACK. The main interest of SPACK is the automatic generation of lumped species related to fast equilibria. We also developped a linear tangent model using the automatic differentiation tool named ODYSSEE in order to perform a sensitivity analysis of an atmospheric multi- phase mechanism based on RADM2 kinetic scheme.Local sensitivity coefficients are computed for two different scenarii. We focus in this study on the sensitivity of the ozone,NOx,HOx, system with respect to some aqueous phase reactions and we inves- tigate the influence of the reduction in the photolysis rates in the area below the cloud region.
Biogas production enhancement using semi-aerobic pre-aeration in a hybrid bioreactor landfill.
Cossu, Raffaello; Morello, Luca; Raga, Roberto; Cerminara, Giulia
2016-09-01
Landfilling continues to be one of the main methods used in managing Municipal Solid Waste (MSW) worldwide, particularly in developing countries. Although in many countries national legislation aims to reduce this practice as much as possible, landfill is a necessary and unavoidable step in closing the material cycle. The need for innovative waste management techniques to improve landfill management and minimize the adverse environmental impact produced has resulted in an increasing interest in innovative systems capable of accelerating waste stabilization. Landfill bioreactors allow decomposition kinetics to be increased and post-operational phase to be shortened; in particular, hybrid bioreactors combine the benefits afforded by both aerobic and anaerobic processes. Six bioreactor simulators were used in the present study: four managed as hybrid, with an initial semi-aerobic phase and a second anaerobic phase, and two as anaerobic control bioreactors. The main goal of the first aerated phase is to reduce Volatile Fatty Acids (VFA) in order to increase pH and enhance methane production during the anaerobic phase; for this reason, air injection was stopped only when these parameters reached the optimum range for methanogenic bacteria. Biogas and leachate were constantly monitored throughout the entire methanogenic phase with the aim of calibrating a Gompertz Model and evaluating the effects of pre-aeration on subsequent methane production. The results showed that moderate and intermittent pre-aeration produces a positive effect both on methane potential and in the kinetics of reaction. Copyright © 2015 Elsevier Ltd. All rights reserved.
Auroras observations of the MAIN in Apatity during 2014/15 winter season
NASA Astrophysics Data System (ADS)
Guineva, V.; Despirak, I.; Kozelov, B.
2017-08-01
In this work we review substorms, originated during the 2014/2015 winter season. Observations of the Multiscale Aurora Imaging Network (MAIN) in Apatity have been used. Solar wind and interplanetary magnetic field parameters were estimated by the 1-min sampled OMNI data base from CDAWeb (http://cdaweb.gsfc.nasa.gov/cdaweb/ istp_public/). Auroral disturbances were verified by the 10-s sampled data of IMAGE magnetometers and by data of the all-sky camera at Apatity. Subject of the review were the peculiarities in the development of substorms occurred during different geomagnetic conditions. The behavior of the substorms developed in non-storm time and during different phases of geomagnetic storms was discussed.
Improving Mixed-phase Cloud Parameterization in Climate Model with the ACRF Measurements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Zhien
Mixed-phase cloud microphysical and dynamical processes are still poorly understood, and their representation in GCMs is a major source of uncertainties in overall cloud feedback in GCMs. Thus improving mixed-phase cloud parameterizations in climate models is critical to reducing the climate forecast uncertainties. This study aims at providing improved knowledge of mixed-phase cloud properties from the long-term ACRF observations and improving mixed-phase clouds simulations in the NCAR Community Atmosphere Model version 5 (CAM5). The key accomplishments are: 1) An improved retrieval algorithm was developed to provide liquid droplet concentration for drizzling or mixed-phase stratiform clouds. 2) A new ice concentrationmore » retrieval algorithm for stratiform mixed-phase clouds was developed. 3) A strong seasonal aerosol impact on ice generation in Arctic mixed-phase clouds was identified, which is mainly attributed to the high dust occurrence during the spring season. 4) A suite of multi-senor algorithms was applied to long-term ARM observations at the Barrow site to provide a complete dataset (LWC and effective radius profile for liquid phase, and IWC, Dge profiles and ice concentration for ice phase) to characterize Arctic stratiform mixed-phase clouds. This multi-year stratiform mixed-phase cloud dataset provides necessary information to study related processes, evaluate model stratiform mixed-phase cloud simulations, and improve model stratiform mixed-phase cloud parameterization. 5). A new in situ data analysis method was developed to quantify liquid mass partition in convective mixed-phase clouds. For the first time, we reliably compared liquid mass partitions in stratiform and convective mixed-phase clouds. Due to the different dynamics in stratiform and convective mixed-phase clouds, the temperature dependencies of liquid mass partitions are significantly different due to much higher ice concentrations in convective mixed phase clouds. 6) Systematic evaluations of mixed-phase cloud simulations by CAM5 were performed. Measurement results indicate that ice concentrations control stratiform mixed-phase cloud properties. The improvement of ice concentration parameterization in the CAM5 was done in close collaboration with Dr. Xiaohong Liu, PNNL (now at University of Wyoming).« less
Idaho Math Initiative. Public School Information. Legislative Report, 2008
ERIC Educational Resources Information Center
Idaho State Department of Education, 2008
2008-01-01
The Idaho Math Initiative has been developed to help raise student achievement in mathematics across all K-12 grades, focusing on three main areas: teacher education, student achievement, and public awareness. This report describes the initial phase of the Math Initiative, including: (1) Assessment; (2) Intervention; (3) Standards; (4) Curriculum;…
"Constructing" the Cell Cycle in 3D
ERIC Educational Resources Information Center
Koc, Isil; Turan, Merve
2012-01-01
The cycle of duplication and division, known as the "cell cycle," is the essential mechanism by which all living organisms reproduce. This activity allows students to develop an understanding of the main events that occur during the typical eukaryotic cell cycle mostly in the process of mitotic phase that divides the duplicated genetic material…
Chen, Wenduo; Zhu, Youliang; Cui, Fengchao; Liu, Lunyang; Sun, Zhaoyan; Chen, Jizhong; Li, Yunqi
2016-01-01
Gay-Berne (GB) potential is regarded as an accurate model in the simulation of anisotropic particles, especially for liquid crystal (LC) mesogens. However, its computational complexity leads to an extremely time-consuming process for large systems. Here, we developed a GPU-accelerated molecular dynamics (MD) simulation with coarse-grained GB potential implemented in GALAMOST package to investigate the LC phase transitions for mesogens in small molecules, main-chain or side-chain polymers. For identical mesogens in three different molecules, on cooling from fully isotropic melts, the small molecules form a single-domain smectic-B phase, while the main-chain LC polymers prefer a single-domain nematic phase as a result of connective restraints in neighboring mesogens. The phase transition of side-chain LC polymers undergoes a two-step process: nucleation of nematic islands and formation of multi-domain nematic texture. The particular behavior originates in the fact that the rotational orientation of the mesogenes is hindered by the polymer backbones. Both the global distribution and the local orientation of mesogens are critical for the phase transition of anisotropic particles. Furthermore, compared with the MD simulation in LAMMPS, our GPU-accelerated code is about 4 times faster than the GPU version of LAMMPS and at least 200 times faster than the CPU version of LAMMPS. This study clearly shows that GPU-accelerated MD simulation with GB potential in GALAMOST can efficiently handle systems with anisotropic particles and interactions, and accurately explore phase differences originated from molecular structures.
Cui, Fengchao; Liu, Lunyang; Sun, Zhaoyan; Chen, Jizhong; Li, Yunqi
2016-01-01
Gay-Berne (GB) potential is regarded as an accurate model in the simulation of anisotropic particles, especially for liquid crystal (LC) mesogens. However, its computational complexity leads to an extremely time-consuming process for large systems. Here, we developed a GPU-accelerated molecular dynamics (MD) simulation with coarse-grained GB potential implemented in GALAMOST package to investigate the LC phase transitions for mesogens in small molecules, main-chain or side-chain polymers. For identical mesogens in three different molecules, on cooling from fully isotropic melts, the small molecules form a single-domain smectic-B phase, while the main-chain LC polymers prefer a single-domain nematic phase as a result of connective restraints in neighboring mesogens. The phase transition of side-chain LC polymers undergoes a two-step process: nucleation of nematic islands and formation of multi-domain nematic texture. The particular behavior originates in the fact that the rotational orientation of the mesogenes is hindered by the polymer backbones. Both the global distribution and the local orientation of mesogens are critical for the phase transition of anisotropic particles. Furthermore, compared with the MD simulation in LAMMPS, our GPU-accelerated code is about 4 times faster than the GPU version of LAMMPS and at least 200 times faster than the CPU version of LAMMPS. This study clearly shows that GPU-accelerated MD simulation with GB potential in GALAMOST can efficiently handle systems with anisotropic particles and interactions, and accurately explore phase differences originated from molecular structures. PMID:26986851
CYP2D6 *6/*6 genotype and drug interactions as cause of haloperidol-induced extrapyramidal symptoms.
Šimić, Iveta; Potočnjak, Ines; Kraljičković, Iva; Stanić Benić, Mirjana; Čegec, Ivana; Juričić Nahal, Danica; Ganoci, Lana; Božina, Nada
2016-08-01
A 66-year-old male Caucasian, received 1 mg of haloperidol orally and rapidly developed severe iatrogenic extrapyramidal symptoms. Treatment was immediately discontinued, and the side effects resolved. Haloperidol is mainly metabolized by Phase I CYP2D6 and to the lesser extent by CYP3A4 and by Phase II UGT2B7 enzymes. Genotyping was performed revealing CYP2D6*6/*6, CYP3A4*1/*1, and UGT2B7 -161 C/T genotypes, implicating poor, extensive and intermediate metabolism, respectively. Of the CYPs, haloperidol is metabolized by CYP2D6 and CYP3A4 primarily. It was the introduction of ciprofloxacin which was a trigger for the development of adverse drug reaction due to inhibition of CYP3A4, which was in presented patient main metabolic pathway for haloperidol since he was CYP2D6 poor metabolizer. Presented case report highlights the importance of genotyping. Pharmacogenetics testing should be considered when drug toxicity is suspected, polymorphic metabolic pathways used and drugs concomitantly applied.
The source of O+ in the storm time ring current
NASA Astrophysics Data System (ADS)
Kistler, L. M.; Mouikis, C. G.; Spence, H. E.; Menz, A. M.; Skoug, R. M.; Funsten, H. O.; Larsen, B. A.; Mitchell, D. G.; Gkioulidou, M.; Wygant, J. R.; Lanzerotti, L. J.
2016-06-01
A stretched and compressed geomagnetic field occurred during the main phase of a geomagnetic storm on 1 June 2013. During the storm the Van Allen Probes spacecraft made measurements of the plasma sheet boundary layer and observed large fluxes of O+ ions streaming up the field line from the nightside auroral region. Prior to the storm main phase there was an increase in the hot (>1 keV) and more isotropic O+ ions in the plasma sheet. In the spacecraft inbound pass through the ring current region during the storm main phase, the H+ and O+ ions were significantly enhanced. We show that this enhanced inner magnetosphere ring current population is due to the inward adiabatic convection of the plasma sheet ion population. The energy range of the O+ ion plasma sheet that impacts the ring current most is found to be from ~5 to 60 keV. This is in the energy range of the hot population that increased prior to the start of the storm main phase, and the ion fluxes in this energy range only increase slightly during the extended outflow time interval. Thus, the auroral outflow does not have a significant impact on the ring current during the main phase. The auroral outflow is transported to the inner magnetosphere but does not reach high enough energies to affect the energy density. We conclude that the more energetic O+ that entered the plasma sheet prior to the main phase and that dominates the ring current is likely from the cusp.
NASA Astrophysics Data System (ADS)
Kotova, D. S.; Klimenko, M. V.; Klimenko, V. V.; Zakharov, V. E.; Ratovsky, K. G.; Nosikov, I. A.; Zhao, B.
2015-11-01
This paper analyses the geomagnetic storm on September 26-29, 2011. We compare the calculation results obtained using the Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP) and IRI-2012 (Bilitza et al., 2014) model with ground-based ionosonde data of stations at different latitudes and longitudes. We examined physical mechanisms responsible for the formation of ionospheric effects during the main phase of geomagnetic storm that occurred at the rising phase of the 24th solar cycle. We used numerical results obtained from IRI-2012 and GSM TIP models as propagation environment for HF signals from an equatorial transmitter during quiet and disturbed conditions. We used the model of HF radio wave propagation developed in I. Kant Baltic Federal University (BFU) that is based on the geometrical optics approximation. We compared the obtained radio paths in quiet conditions and during the main and recovery storm phases and evaluated radio wave attenuation in different media models.
Timing, tempo and paleoenvironmental influence of Deccan volcanism relative to the KT extinction
NASA Astrophysics Data System (ADS)
Adatte, Thierry; Keller, Gerta; Schoene, Blair; Khadri, Syed
2015-04-01
Deccan Traps erupted in three main phases with 6% total Deccan volume in phase-1 (base C30n), 80% in phase-2 (C29r) and 14% in phase-3 (C29n). Recent studies indicate that the bulk (80%) of Deccan trap eruptions (Phase-2) occurred over a relatively short time interval in magnetic polarity C29r (Chenet et al., 2008). Moreover, U-Pb zircon geochronology shows that the main Phase 2 began 250 ka before the Cretaceous-Tertiary (KT) mass extinction, suggesting a cause-and-effect relationship (Blair et al., 2015). In India a strong floral response is observed as a direct consequence of volcanic phase-2. In Lameta (infratrappean) sediments preceding the volcanic eruptions, palynoflora are dominated by gymnosperms and angiosperms (Samant and Mohabey, 2005). Shortly after the onset of Deccan phase-2, this floral association was decimated as indicated by a sharp decrease in pollen and spores coupled with the appearance of fungi, which mark increasing stress conditions apparently as a direct result of volcanic activity. The inter-trappean sediments corresponding to the Phases 2 and 3 are characterized by the highest alteration CIA index values suggesting increased acid rains due to SO2 emissions. Closer to the eruption center, the lava flows are generally separated by red weathered horizons known as red boles, marking a quiescent period between two basalt flows. Red boles consist mainly of red silty clays characterized by concentrations of immobile elements such as Al and Fe3+ ions, which provide indirect evidence of a primitive form of paleo-laterite that probably developed during the short periods of weathering between eruptions. There are at least 15 thick red bole layers in C29r below the KT boundary, and all were deposited in phase-2 volcanic eruptions that occurred over a time span of about 250 ky. These short duration exposures are reflected in the mineralogical and geochemical data that indicate rapid weathering (high CIA) but arid conditions. The arid conditions can be explained by acid rain, which accelerated the weathering process. These observations indicate that Deccan volcanism played a key role in increasing atmospheric CO2 and SO2 levels that resulted in global warming and acidified oceans, thus increasing biotic stress that predisposed faunas to eventual extinction at the KTB.
Investigation into mechanical properties of bone and its main constituents
NASA Astrophysics Data System (ADS)
Evdokimenko, Ekaterina
Bone is a hierarchically structured natural composite material, consisting of organic phase (type-I collagen), inorganic phase (hydroxyapatite), and water. Studies of the two main bone constituents, utilizing controlled demineralization and deproteinization, can shed light on mineral-collagen interaction which makes bone such a unique biological material. This knowledge is necessary for computational analysis of bone structure to identify preferential sites in the collagen matrix and mineral network that degrade more easily. The main goal of this work is to develop a comprehensive picture of mechanical properties of bone and its main constituents. Following the Introduction, Chapter 2 presents an investigation of microstructure and compressive mechanical properties of bovine femur cortical bone carried out on completely demineralized, completely deproteinized, and untreated bone samples in three anatomical directions. Anisotropic nature of bone was clearly identified in all cases. Extra levels of porosity along with microstructural differences for the three directions were found to be the main sources of the anisotropy. In Chapter 3, a new theoretical model of cortical and trabecular bone as composite materials with hierarchical structure spanning from nanometer (collagen-mineral) level to millimeter (bone) level was developed. Compression testing was performed on untreated, demineralized, and deproteinized cortical and trabecular bovine femur bone samples to verify the model. The experimental data were compared with theoretical predictions; excellent agreement was found between the theory and experiments for all bone phases. Optical microscopy, scanning electron microscopy, and micro-computed tomography techniques were applied to characterize the structure of the samples at multiple length scales and provide further inputs for the modeling. Chapter 4 presents a comparative study of mechanical properties, microstructure, and porosity of mature and young bovine femur cortical bone. It was found that the amount of porosity decreases, while the microhardness increases with maturation. Osteoporotic degradation of trabecular bone elasticity, described in Chapter 5, was modeled using a cellular mechanics approach. Evolution equations for elastic modulus of bone in terms of those of mineral and protein trabeculae and in terms of demineralized and deproteinized bones were formulated and verified by the analysis of compressive properties of bovine femur trabecular bone.
Moving formal methods into practice. Verifying the FTPP Scoreboard: Results, phase 1
NASA Technical Reports Server (NTRS)
Srivas, Mandayam; Bickford, Mark
1992-01-01
This report documents the Phase 1 results of an effort aimed at formally verifying a key hardware component, called Scoreboard, of a Fault-Tolerant Parallel Processor (FTPP) being built at Charles Stark Draper Laboratory (CSDL). The Scoreboard is part of the FTPP virtual bus that guarantees reliable communication between processors in the presence of Byzantine faults in the system. The Scoreboard implements a piece of control logic that approves and validates a message before it can be transmitted. The goal of Phase 1 was to lay the foundation of the Scoreboard verification. A formal specification of the functional requirements and a high-level hardware design for the Scoreboard were developed. The hardware design was based on a preliminary Scoreboard design developed at CSDL. A main correctness theorem, from which the functional requirements can be established as corollaries, was proved for the Scoreboard design. The goal of Phase 2 is to verify the final detailed design of Scoreboard. This task is being conducted as part of a NASA-sponsored effort to explore integration of formal methods in the development cycle of current fault-tolerant architectures being built in the aerospace industry.
Runway exit designs for capacity improvement demonstrations. Phase 2: Computer model development
NASA Technical Reports Server (NTRS)
Trani, A. A.; Hobeika, A. G.; Kim, B. J.; Nunna, V.; Zhong, C.
1992-01-01
The development is described of a computer simulation/optimization model to: (1) estimate the optimal locations of existing and proposed runway turnoffs; and (2) estimate the geometric design requirements associated with newly developed high speed turnoffs. The model described, named REDIM 2.0, represents a stand alone application to be used by airport planners, designers, and researchers alike to estimate optimal turnoff locations. The main procedures are described in detail which are implemented in the software package and possible applications are illustrated when using 6 major runway scenarios. The main output of the computer program is the estimation of the weighted average runway occupancy time for a user defined aircraft population. Also, the location and geometric characteristics of each turnoff are provided to the user.
Current status of Kumgang laser system
NASA Astrophysics Data System (ADS)
Kong, Hong Jin; Park, Sangwoo; Ahn, HeeKyung; Lee, Hwihyeong; Oh, Jungsuk; Kim, Jom Sool
2015-02-01
In KAIST, Kumgang laser is being developed for demonstration of the kW level coherent beam combination using stimulated Brillouin scattering phase conjugation mirrors. It will combine 4 modules of DPSSL rod amplifier which produces 1 kW output power. It is composed of the single frequency front-end, pre-amplifier module, and main amplifier. The output powers of the pre-amp and main amplifier module are 200 W (20 mJ @ 10 kHz / 10 ns) and 1.07kW (107 mJ @ 10 kHz / 10 ns), respectively.
Ortiz-Villanueva, Elena; Tauler, Romà
2017-01-01
Metabolomics is a powerful and widely used approach that aims to screen endogenous small molecules (metabolites) of different families present in biological samples. The large variety of compounds to be determined and their wide diversity of physical and chemical properties have promoted the development of different types of hydrophilic interaction liquid chromatography (HILIC) stationary phases. However, the selection of the most suitable HILIC stationary phase is not straightforward. In this work, four different HILIC stationary phases have been compared to evaluate their potential application for the analysis of a complex mixture of metabolites, a situation similar to that found in non-targeted metabolomics studies. The obtained chromatographic data were analyzed by different chemometric methods to explore the behavior of the considered stationary phases. ANOVA-simultaneous component analysis (ASCA), principal component analysis (PCA) and partial least squares regression (PLS) were used to explore the experimental factors affecting the stationary phase performance, the main similarities and differences among chromatographic conditions used (stationary phase and pH) and the molecular descriptors most useful to understand the behavior of each stationary phase. PMID:29064436
NASA Astrophysics Data System (ADS)
Li, M. H.; Brûlet, A.; Keller, P.; Cotton, J. P.
1996-09-01
This article describes the conformation of two species of liquid crystalline polymers as revealed by small angle neutron scattering. The results obtained with side chain polymers are recalled. The procedure used to analyze the scattering data of main chains in the nematic phase is reported in this paper. It permits a demonstration of the existence of hairpins. Comparison of both polymer species shows that in the isotropic phase, the two polymers adopt a random coil conformation. In the nematic phase, the conformations are very different; the side chains behave as a melt of penetrable random coils whereas the main chains behave as a nematic phase of non penetrable cylinders.
Folta, Sara C; Koomas, Alyssa; Metayer, Nesly; Fullerton, Karen J; Hubbard, Kristie L; Anzman-Frasca, Stephanie; Hofer, Teresa; Nelson, Miriam; Newman, Molly; Sacheck, Jennifer; Economos, Christina
2015-12-24
Little effort has focused on the role of volunteer-led out-of-school time (OST) programs (ie, enrichment and sports programs) as key environments for the promotion of healthy eating and physical activity habits among school-aged children. The Healthy Kids Out of School (HKOS) initiative developed evidence-based, practical guiding principles for healthy snacks, beverages, and physical activity. The goal of this case study was to describe the methods used to engage regional partners to understand how successful implementation and dissemination of these principles could be accomplished. HKOS partnered with volunteer-led programs from 5 OST organizations in Maine, Massachusetts, and New Hampshire to create a regional "learning laboratory." We engaged partners in phases. In the first phase, we conducted focus groups with local volunteer program leaders; during the second phase, we held roundtable meetings with regional and state program administrators; and in the final phase, we conducted additional outreach to refine and finalize implementation strategies. Implementation strategies were developed based on themes and information that emerged. For enrichment programs, strategies included new patch and pin programs that were consistent with the organizations' infrastructure and usual practices. For sports programs, the main strategy was integration with online trainings for coaches. Through the engagement process, we learned that dissemination of the guiding principles in these large and complex OST organizations was best accomplished by using implementation strategies that were customized, integrated, and aligned with goals and usual practices. The lessons learned can benefit future efforts to prevent obesity in complex environments.
Logo recognition using alpha-rooted phase correlation in the radon transform domain
NASA Astrophysics Data System (ADS)
DelMarco, Stephen
2009-08-01
Alpha-rooted phase correlation (ARPC) is a recently-developed variant of classical phase correlation that includes a Fourier domain image enhancement operation. ARPC combines classical phase correlation with alpha-rooting to provide tunable image enhancement. The alpha-rooting parameters may be adjusted to provide a tradeoff between height and width of the ARPC main lobe. A high narrow main lobe peak provides high matching accuracy for aligned images, but reduced matching performance for misaligned logos. A lower, wider peak trades matching accuracy on aligned logos, for improved matching performance on misaligned imagery. Previously, we developed ARPC and used it in the spatial domain for logo recognition as part of an overall automated document analysis problem. However, spatial domain ARPC performance can be sensitive to logo misalignments, including rotational misalignment. In this paper we use ARPC as a match metric in the radon transform domain for logo recognition. In the radon transform domain, rotational misalignments correspond to translations in the radon transform angle parameter. These translations are captured by ARPC, thereby producing rotation-invariant logo matching. In the paper, we first present an overview of ARPC, and then describe the logo matching algorithm. We present numerical performance results demonstrating matching tolerance to rotational misalignments. We demonstrate robustness of the radon transform domain rotation estimation to noise. We present logo verification and recognition performance results using the proposed approach on a public domain logo database. We compare performance results to performance obtained using spatial domain ARPC, and state-of-the-art SURF features, for logos in salt-and-pepper noise.
Signaling molecules involved in the transition of growth to development of Dictyostelium discoideum.
Mir, Hina A; Rajawat, Jyotika; Pradhan, Shalmali; Begum, Rasheedunnisa
2007-03-01
The social amoeba Dictyostelium discoideum, a powerful paradigm provides clear insights into the regulation of growth and development. In addition to possessing complex individual cellular functions like a unicellular eukaryote, D. discoideum cells face the challenge of multicellular development. D. discoideum undergoes a relatively simple differentiation process mainly by cAMP mediated pathway. Despite this relative simplicity, the regulatory signaling pathways are as complex as those seen in metazoan development. However, the introduction of restriction-enzyme-mediated integration (REMI) technique to produce developmental gene knockouts has provided novel insights into the discovery of signaling molecules and their role in D. discoideum development. Cell cycle phase is an important aspect for differentiation of D. discoideum, as cells must reach a specific stage to enter into developmental phase and specific cell cycle regulators are involved in arresting growth phase genes and inducing the developmental genes. In this review, we present an overview of the signaling molecules involved in the regulation of growth to differentiation transition (GDT), molecular mechanism of early developmental events leading to generation of cAMP signal and components of cAMP relay system that operate in this paradigm.
NASA Astrophysics Data System (ADS)
Omer, Muhamed F.; Friis, Henrik
2014-03-01
The Ordovician deltaic to shallow marine Khabour Formation in Northern Iraq consists mainly of sandstone with minor siltstone and interbedded shale. The sandstones are pervasively cemented by quartz that resulted in very little preserved primary porosity. Cathodoluminescence and petrographic studies showed that the silica cementation occurred in five successive phases which can be distinguished by their luminescence pattern. The precipitations of two phases have predated the major compaction process while the other phases are younger. The successive phases represent a sequence of changes in silica supply which were classified as very early and early, derived from dissolved biogenic silica that precipitated as opal/microquartz, possibly pre-compactional and of non-luminescent quartz overgrowth type. This was followed by phases whose silica supply derived from pressure solution of quartz, dissolution of feldspar, and hydrothermal fluids related to major thrust fault event. These successive quartz cement phases showed an increase in luminescence and the development of complicated zonation pattern in late-stage quartz cementation.
Phased Array Radar Network Experiment for Severe Weather
NASA Astrophysics Data System (ADS)
Ushio, T.; Kikuchi, H.; Mega, T.; Yoshikawa, E.; Mizutani, F.; Takahashi, N.
2017-12-01
Phased Array Weather Radar (PAWR) was firstly developed in 2012 by Osaka University and Toshiba under a grant of NICT using the Digital Beamforming Technique, and showed a impressive thunderstorm behavior with 30 second resolution. After that development, second PAWR was installed in Kobe city about 60 km away from the first PAWR site, and Tokyo Metropolitan University, Osaka Univeristy, Toshiba and the Osaka Local Government started a new project to develop the Osaka Urban Demonstration Network. The main sensor of the Osaka Network is a 2-node Phased Array Radar Network and lightning location system. Data products that are created both in local high performance computer and Toshiba Computer Cloud, include single and multi-radar data, vector wind, quantitative precipitation estimation, VIL, nowcasting, lightning location and analysis. Each radar node is calibarated by the baloon measurement and through the comparison with the GPM (Global Precipitation Measurement)/ DPR (Dual Frequency Space borne Radar) within 1 dB. The attenuated radar reflectivities obtained by the Phased Array Radar Network at X band are corrected based on the bayesian scheme proposed in Shimamura et al. [2016]. The obtained high resolution (every 30 seconds/ 100 elevation angles) 3D reflectivity and rain rate fields are used to nowcast the surface rain rate up to 30 minutes ahead. These new products are transferred to Osaka Local Government in operational mode and evaluated by several section in Osaka Prefecture. Furthermore, a new Phased Array Radar with polarimetric function has been developed in 2017, and will be operated in the fiscal year of 2017. In this presentation, Phased Array Radar, network architecuture, processing algorithm, evalution of the social experiment and first Multi-Prameter Phased Array Radar experiment are presented.
Zhu, Jianting; Sun, Dongmin
2016-09-01
Groundwater flowing through residual nonaqueous phase liquid (NAPL) source zone will cause NAPL dissolution and generate large contaminant plume. The use of contaminant mass discharge (CMD) measurements in addition to NAPL aqueous phase concentration to characterize site conditions and assess remediation performance is becoming popular. In this study, we developed new and generic numerical models to investigate the significance of groundwater flux temporal variations on the NAPL source dynamics. The developed models can accommodate any temporal variations of groundwater flux in the source zone. We examined the various features of groundwater flux using a few selected functional forms of linear increase/decrease, gradual smooth increase/decrease, and periodic fluctuations with a general trend. Groundwater flux temporal variations have more pronounced effects on the contaminant mass discharge dynamics than the aqueous concentration. If the groundwater flux initially increases, then the reduction in contaminant mass discharge (CMDR) vs. NAPL mass reduction (MR) relationship is mainly downward concave. If the groundwater flux initially decreases, then CMDR vs. MR relationship is mainly upward convex. If the groundwater flux variations are periodic, the CMDR vs. MR relationship tends to also have periodic variations ranging from upward convex to downward concave. Eventually, however, the CMDR vs. MR relationship approaches 1:1 when majority of the NAPL mass becomes depleted. Copyright © 2016 Elsevier B.V. All rights reserved.
Study on microstructure and strengthening mechanism of AZ91-Y magnesium alloy
NASA Astrophysics Data System (ADS)
Cai, Huisheng; Guo, Feng; Su, Juan; Liu, Liang; Chen, Baodong
2018-03-01
AZ91-Y magnesium alloy with different thicknesses were prepared by die casting process. The main existence forms of Y in alloy and the effects of Y on microstructure and mechanical properties of alloy were studied, the main reason for the change of mechanical properties and fracture mechanism were analyzed. The results show that, yttrium exists mainly in the forms of Al2Y phase and trace solid solution in α-Mg. Yttrium can refine the grain of α-Mg, reduce the amount of eutectic β-Mg17Al12 phase and promote its discrete distribution. The room temperature tensile strength and elongation of alloy increased first and then decreased with the increase of Y content. The designed alloys containing 0.6% Y (measured containing 0.63% Y) have better mechanical properties. The change of mechanical properties of alloy is a comprehensive reflection of the effect of solid solution, grain refinement and second phase. The cracking of Al2Y phase and β-Mg17Al12 phase and crack propagation through Al2Y phase and β-Mg17Al12 phase are the main fracture mechanism of magnesium alloy containing yttrium. The cooling rate does not change the trend of the influence of Y, but affects the degree of influence of Y.
NASA Astrophysics Data System (ADS)
Chen, Ya-Zhou; Zhou, Liu-Cheng; He, Wei-Feng; Sun, Yu; Li, Ying-Hong; Jiao, Yang; Luo, Si-Hai
2017-01-01
Molecular dynamics simulations were used to study the plastic behavior of monocrystalline nickel under shock compression along the [100] and [110] orientations. The shock Hugoniot relation, local stress curve, and process of microstructure development were determined. Results showed the apparent anisotropic behavior of monocrystalline nickel under shock compression. The separation of elastic and plastic waves was also obvious. Plastic deformation was more severely altered along the [110] direction than the [100] direction. The main microstructure phase transformed from face-centered cubic to body-centered cubic and generated a large-scale and low-density stacking fault along the family of { 111 } crystal planes under shock compression along the [100] direction. By contrast, the main mechanism of plastic deformation in the [110] direction was the nucleation of the hexagonal, close-packed phase, which generated a high density of stacking faults along the [110] and [1̅10] directions.
Time-Series INSAR: An Integer Least-Squares Approach For Distributed Scatterers
NASA Astrophysics Data System (ADS)
Samiei-Esfahany, Sami; Hanssen, Ramon F.
2012-01-01
The objective of this research is to extend the geode- tic mathematical model which was developed for persistent scatterers to a model which can exploit distributed scatterers (DS). The main focus is on the integer least- squares framework, and the main challenge is to include the decorrelation effect in the mathematical model. In order to adapt the integer least-squares mathematical model for DS we altered the model from a single master to a multi-master configuration and introduced the decorrelation effect stochastically. This effect is described in our model by a full covariance matrix. We propose to de- rive this covariance matrix by numerical integration of the (joint) probability distribution function (PDF) of interferometric phases. This PDF is a function of coherence values and can be directly computed from radar data. We show that the use of this model can improve the performance of temporal phase unwrapping of distributed scatterers.
The pervasive role of social learning in primate lifetime development.
Whiten, Andrew; van de Waal, Erica
2018-01-01
In recent decades, an accelerating research effort has exploited a substantial diversity of methodologies to garner mounting evidence for social learning and culture in many species of primate. As in humans, the evidence suggests that the juvenile phases of non-human primates' lives represent a period of particular intensity in adaptive learning from others, yet the relevant research remains scattered in the literature. Accordingly, we here offer what we believe to be the first substantial collation and review of this body of work and its implications for the lifetime behavioral ecology of primates. We divide our analysis into three main phases: a first phase of learning focused on primary attachment figures, typically the mother; a second phase of selective learning from a widening array of group members, including some with expertise that the primary figures may lack; and a third phase following later dispersal, when a migrant individual encounters new ecological and social circumstances about which the existing residents possess expertise that can be learned from. Collating a diversity of discoveries about this lifetime process leads us to conclude that social learning pervades primate ontogenetic development, importantly shaping locally adaptive knowledge and skills that span multiple aspects of the behavioral repertoire.
ROBIS: A new tool to assess risk of bias in systematic reviews was developed.
Whiting, Penny; Savović, Jelena; Higgins, Julian P T; Caldwell, Deborah M; Reeves, Barnaby C; Shea, Beverley; Davies, Philippa; Kleijnen, Jos; Churchill, Rachel
2016-01-01
To develop ROBIS, a new tool for assessing the risk of bias in systematic reviews (rather than in primary studies). We used four-stage approach to develop ROBIS: define the scope, review the evidence base, hold a face-to-face meeting, and refine the tool through piloting. ROBIS is currently aimed at four broad categories of reviews mainly within health care settings: interventions, diagnosis, prognosis, and etiology. The target audience of ROBIS is primarily guideline developers, authors of overviews of systematic reviews ("reviews of reviews"), and review authors who might want to assess or avoid risk of bias in their reviews. The tool is completed in three phases: (1) assess relevance (optional), (2) identify concerns with the review process, and (3) judge risk of bias. Phase 2 covers four domains through which bias may be introduced into a systematic review: study eligibility criteria; identification and selection of studies; data collection and study appraisal; and synthesis and findings. Phase 3 assesses the overall risk of bias in the interpretation of review findings and whether this considered limitations identified in any of the phase 2 domains. Signaling questions are included to help judge concerns with the review process (phase 2) and the overall risk of bias in the review (phase 3); these questions flag aspects of review design related to the potential for bias and aim to help assessors judge risk of bias in the review process, results, and conclusions. ROBIS is the first rigorously developed tool designed specifically to assess the risk of bias in systematic reviews. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
ROBIS: A new tool to assess risk of bias in systematic reviews was developed
Whiting, Penny; Savović, Jelena; Higgins, Julian P.T.; Caldwell, Deborah M.; Reeves, Barnaby C.; Shea, Beverley; Davies, Philippa; Kleijnen, Jos; Churchill, Rachel
2016-01-01
Objective To develop ROBIS, a new tool for assessing the risk of bias in systematic reviews (rather than in primary studies). Study Design and Setting We used four-stage approach to develop ROBIS: define the scope, review the evidence base, hold a face-to-face meeting, and refine the tool through piloting. Results ROBIS is currently aimed at four broad categories of reviews mainly within health care settings: interventions, diagnosis, prognosis, and etiology. The target audience of ROBIS is primarily guideline developers, authors of overviews of systematic reviews (“reviews of reviews”), and review authors who might want to assess or avoid risk of bias in their reviews. The tool is completed in three phases: (1) assess relevance (optional), (2) identify concerns with the review process, and (3) judge risk of bias. Phase 2 covers four domains through which bias may be introduced into a systematic review: study eligibility criteria; identification and selection of studies; data collection and study appraisal; and synthesis and findings. Phase 3 assesses the overall risk of bias in the interpretation of review findings and whether this considered limitations identified in any of the phase 2 domains. Signaling questions are included to help judge concerns with the review process (phase 2) and the overall risk of bias in the review (phase 3); these questions flag aspects of review design related to the potential for bias and aim to help assessors judge risk of bias in the review process, results, and conclusions. Conclusions ROBIS is the first rigorously developed tool designed specifically to assess the risk of bias in systematic reviews. PMID:26092286
Xing, Mingfei; Wang, Jingyu; Fu, Zegang; Zhang, Donghui; Wang, Yaping; Zhang, Zhiyuan
2018-04-05
In this study, a novel process for the extraction of heavy metal Ba and Sr from waste CRT panel glass and synchronous preparation of high silica glass powder was developed by glass phase separation. CRT panel glass was first remelted with B 2 O 3 under air atmosphere to produce alkali borosilicate glass. During the phase separation process, the glass separated into two interconnected phases which were B 2 O 3 -rich phase and SiO 2 -rich phase. Most of BaO, SrO and other metal oxides including Na 2 O, K 2 O, Al 2 O 3 and CaO were mainly concentrated in the B 2 O 3 -rich phase. The interconnected B 2 O 3 -rich phase can be completely leached out by 5mol/L HNO 3 at 90 ℃. The remaining SiO 2 -rich phase was porous glasses consisting almost entirely of silica. The maximum Ba and Sr removal rates were 98.84% and 99.38% and high silica glass powder (SiO 2 purity > 90 wt%) was obtained by setting the temperature, B 2 O 3 added amount and holding time at 1000-1100 ℃, 20-30% and 30 min, respectively. Thus this study developed an potential economical process for detoxification and reclamation of waste heavy metal glasses. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Taddei, Arnaud
After it had been decided to design a common user environment for UNIX platforms among HEP laboratories, a joint project between DESY and CERN had been started. The project consists in 2 phases: 1. Provide a common user environment at shell level, 2. Provide a common user environment at graphical level (X11). Phase 1 is in production at DESY and at CERN as well as at PISA and RAL. It has been developed around the scripts originally designed at DESY Zeuthen improved and extended with a 2 months project at CERN with a contribution from DESY Hamburg. It consists of a set of files which are customizing the environment for the 6 main shells (sh, csh, ksh, bash, tcsh, zsh) on the main platforms (AIX, HP-UX, IRIX, SunOS, Solaris 2, OSF/1, ULTRIX, etc.) and it is divided at several "sociological" levels: HEP, site, machine, cluster, group of users and user with some levels which are optional. The second phase is under design and a first proposal has been published. A first version of the phase 2 exists already for AIX and Solaris, and it should be available for all other platforms, by the time of the conference. This is a major collective work between several HEP laboratories involved in the HEPiX-scripts and HEPiX-X11 working-groups.
NASA Astrophysics Data System (ADS)
Edmond, J. A.; Hill, S. C.; Xu, H.; Perez, J. D.; Fok, M. C. H.; Goldstein, J.; McComas, D. J.; Valek, P. W.
2017-12-01
The Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) mission obtained energetic neutral atom (ENA) images during a 4 day storm on 7-10 September 2015. The storm has two separate SYM/H minima, so we divide the storm into four intervals: first main phase, first recovery phase, second main phase, and second recovery phase. Simulations with the Comprehensive Inner Magnetosphere-Ionosphere Model (CIMI) are compared and contrasted with the TWINS observations. We find good agreement in most aspects of the storm. E. G. (1) the location of the ion pressure peaks are most often in the dusk-midnight sector, (2) the pitch angle distributions at the pressure peaks most often display perpendicular anisotropy, and (3) the energy spectra at the pressure peaks have similar maximum energies. There are, however, some exceptions to these general features. We describe and interpret these notable events. We also have examined particle paths determined from the CIMI model simulations to assist in the interpretation of the notable events.In this poster, we focus upon the features of the CIMI simulations with a self-consistent electric field and with the semi-empirical Weimer electric potential in relationship to the TWINS observations.
Design of analytical systems based on functionality of doped ice.
Okada, Tetsuo
2014-01-01
Ice plays an important role for the circulations of some compounds in the global environment. Both the ice surface and the liquid phase developed in a frozen solution are involved in such reactions of the molecules of environmental importance. This leads to the idea that ice can be used to design novel analytical reaction systems. We devised ice chromatography, in which ice particles are used as the liquid chromatographic stationary phase, and have subsequently developed various analytical systems utilizing the functionality of ice. This review focuses our attention on the analytical facets of ice containing impurities such as salts; hereinafter, we call this "doped ice". The design of novel separation systems and use as microreactors with doped ice are mainly discussed.
NASA Astrophysics Data System (ADS)
Chzhu, O. P.; Shubenkova, E. G.
2017-08-01
Liposomal structures were developed on the basis of oil and water extracts of natural organomineral formations. These structures are natural compositions. The content of the main components in the preparations varies within the range of 20-25% of the lipophilic phase, 64-74% of the hydrophilic phase, 5-10% of the auxiliary component and the stabilizer on the phospholipid base is 1%. Phospholipids of natural origin were used as surface-active substances. The influence of hydrophilic and lipophilic auxiliary components on the content of neutral lipids in the surface lipid layer of the skin was studied. The developed preparations can be used as carriers of both hydrophilic and lipophilic active substances in pharmaceutical compositions, cosmetic and veterinary products on a natural basis.
Micromagnetic simulations with periodic boundary conditions: Hard-soft nanocomposites
Wysocki, Aleksander L.; Antropov, Vladimir P.
2016-12-01
Here, we developed a micromagnetic method for modeling magnetic systems with periodic boundary conditions along an arbitrary number of dimensions. The main feature is an adaptation of the Ewald summation technique for evaluation of long-range dipolar interactions. The method was applied to investigate the hysteresis process in hard-soft magnetic nanocomposites with various geometries. The dependence of the results on different micromagnetic parameters was studied. We found that for layered structures with an out-of-plane hard phase easy axis the hysteretic properties are very sensitive to the strength of the interlayer exchange coupling, as long as the spontaneous magnetization for the hardmore » phase is significantly smaller than for the soft phase. The origin of this behavior was discussed. Additionally, we investigated the soft phase size optimizing the energy product of hard-soft nanocomposites.« less
Field-circuit analysis and measurements of a single-phase self-excited induction generator
NASA Astrophysics Data System (ADS)
Makowski, Krzysztof; Leicht, Aleksander
2017-12-01
The paper deals with a single-phase induction machine operating as a stand-alone self-excited single-phase induction generator for generation of electrical energy from renewable energy sources. By changing number of turns and size of wires in the auxiliary stator winding, an improvement of performance characteristics of the generator were obtained as regards no-load and load voltage of the stator windings as well as stator winding currents of the generator. Field-circuit simulation models of the generator were developed using Flux2D software package for the generator with shunt capacitor in the main stator winding. The obtained results have been validated experimentally at the laboratory setup using the single-phase capacitor induction motor of 1.1 kW rated power and 230 V voltage as a base model of the generator.
NASA Astrophysics Data System (ADS)
Biswas, Anirban; Henkel, Karsten; Schmeißer, Dieter; Mandal, Dipankar
2017-12-01
The electroactive β phase of poly(vinylidene fluoride) (PVDF) is induced due to the aging time of PVDF solutions. The feasibility of the combination of the three crystalline polymorphs (α, β and γ) is demonstrated where their relative proportion within the PVDF film can be tailored by the simple monitoring of the preparation conditions. To identify all these phases, Fourier transform infrared (FT-IR) spectroscopy is carried out and it is spotlighted that the vibrational bands at 510 and 841 cm-1 are not sufficient to state the formation of the β phase. The main aim of this work is devoted to develop a better understanding on the thermal stability of these several phases of PVDF, which has a longstanding ambiguity persisting in this area. It has been found that the in situ thermal FT-IR spectroscopy is one of the best alternatives to understand this important issue. It is ascertained that the β phase is the least thermally stable phase among α, β and γ phases, whereas the γ phase is the most thermally stable phase.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simunovic, Srdjan; Piro, Markus H.A.
Thermochimica is a software library that determines a unique combination of phases and their compositions at thermochemical equilibrium. Thermochimica can be used for stand-alone calculations or it can be directly coupled to other codes. This release of the software does not have a graphical user interface (GUI) and it can be executed from the command line or from an Application Programming Interface (API). Also, it is not intended for thermodynamic model development or for constructing phase diagrams. The main purpose of the software is to be directly coupled with a multi-physics code to provide material properties and boundary conditions formore » various physical phenomena. Significant research efforts have been dedicated to enhance computational performance through advanced algorithm development, such as improved estimation techniques and non-linear solvers. Various useful parameters can be provided as output from Thermochimica, such as: determination of which phases are stable at equilibrium, the mass of solution species and phases at equilibrium, mole fractions of solution phase constituents, thermochemical activities (which are related to partial pressures for gaseous species), chemical potentials of solution species and phases, and integral Gibbs energy (referenced relative to standard state). The overall goal is to provide an open source computational tool to enhance the predictive capability of multi-physics codes without significantly impeding computational performance.« less
Scenario Development for the Southwestern United States
NASA Astrophysics Data System (ADS)
Mahmoud, M.; Gupta, H.; Stewart, S.; Liu, Y.; Hartmann, H.; Wagener, T.
2006-12-01
The primary goal of employing a scenario development approach for the U.S. southwest is to inform regional policy by examining future possibilities related to regional vegetation change, water-leasing, and riparian restoration. This approach is necessary due to a lack of existing explicit water resources application of scenarios to the entire southwest region. A formal approach for scenario development is adopted and applied towards water resources issues within the arid and semi-arid regions of the U.S. southwest following five progressive and reiterative phases: scenario definition, scenario construction, scenario analysis, scenario assessment, and risk management. In the scenario definition phase, the inputs of scientists, modelers, and stakeholders were collected in order to define and construct relevant scenarios to the southwest and its water sustainability needs. From stakeholder-driven scenario workshops and breakout sessions, the three main axes of principal change were identified to be climate change, population development patterns, and quality of information monitoring technology. Based on the extreme and varying conditions of these three main axes, eight scenario narratives were drafted to describe the state of each scenario's respective future and the events which led to it. Events and situations are described within each scenario narrative with respect to key variables; variables that are both important to regional water resources (as distinguished by scientists and modelers), and are good tracking and monitoring indicators of change. The current phase consists of scenario construction, where the drafted scenarios are re-presented to regional scientists and modelers to verify that proper key variables are included (or excluded) from the eight narratives. The next step is to construct the data sets necessary to implement the eight scenarios on the respective computational models of modelers investigating vegetation change, water-leasing, and riparian restoration in the southwest
NASA Astrophysics Data System (ADS)
Pfefferkorn, T.; Oxynos, C.; Greff, P.; Gerlach, L.
2008-09-01
After the successful series of Eurostar 3000 and Spacebus 4000 satellites and due to the demand of satellite operators for even larger and more powerful satellites, ESA decided to co-fund the development of a new satellite platform which covers the market segment beyond the upper limits of both satellite families.The new satellite bus family Alphabus is developed in the frame of ARTES 8 project by a joint project team of ASTRIUM and TAS, whereas the solar array is developed by ASTRIUM GmbH.The main approaches in this design phase for the Alphabus solar array were to find a standardized and scaleable design to production and to use qualification heritage from former projects, especially Eurostar 3000, as far as possible. The main challenges for the solar array design and test philosophy were the usage of lateral deployment and related sequential deployment and the bus voltage of 102,5V and related ESD precautions.This paper provides an overview of the different configurations, their main design features and performance parameters. In addition it summarizes the development and verification approach and shows the actual qualification status.
Ehn, Maria; Hansson, Pär; Sjölinder, Marie; Boman, Inga-Lill; Folke, Mia; Sommerfeld, Disa; Borg, Jörgen; Palmcrantz, Susanne
2015-01-01
The aim of this work has been to develop a technical support enabling home-based motor training after stroke. The basis for the work plan has been to develop an interactive technical solution supporting three different groups of stroke patients: (1) patients with stroke discharged from hospital with support from neuro team; (2) patients with stroke whose support from neuro team will be phased out and (3) patients living with impaired motor functions long-term. The technology has been developed in close collaboration with end-users using a method earlier evaluated and described [12]. This paper describes the main functions of the developed technology. Further, results from early user-tests with end-users, performed to identify needs for improvements to be carried out during further technical development. The developed technology will be tested further in a pilot study of the safety and, usefulness of the technology when applied as a support for motor training in three different phases of the post-stroke rehabilitation process.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Babic, Miroslav; Kljenak, Ivo; Mavko, Borut
2006-07-01
The CFD code CFX4.4 was used to simulate an experiment in the ThAI facility, which was designed for investigation of thermal-hydraulic processes during a severe accident inside a Light Water Reactor containment. In the considered experiment, air was initially present in the vessel, and helium and steam were injected during different phases of the experiment at various mass flow rates and at different locations. The main purpose of the simulation was to reproduce the non-homogeneous temperature and species concentration distributions in the ThAI experimental facility. A three-dimensional model of the ThAI vessel for the CFX4.4 code was developed. The flowmore » in the simulation domain was modeled as single-phase. Steam condensation on vessel walls was modeled as a sink of mass and energy using a correlation that was originally developed for an integral approach. A simple model of bulk phase change was also introduced. The calculated time-dependent variables together with temperature and concentration distributions at the end of experiment phases are compared to experimental results. (authors)« less
Susceptibility Tensor Imaging (STI) of the Brain
Li, Wei; Liu, Chunlei; Duong, Timothy Q.; van Zijl, Peter C.M.; Li, Xu
2016-01-01
Susceptibility tensor imaging (STI) is a recently developed MRI technique that allows quantitative determination of orientation-independent magnetic susceptibility parameters from the dependence of gradient echo signal phase on the orientation of biological tissues with respect to the main magnetic field. By modeling the magnetic susceptibility of each voxel as a symmetric rank-2 tensor, individual magnetic susceptibility tensor elements as well as the mean magnetic susceptibility (MMS) and magnetic susceptibility anisotropy (MSA) can be determined for brain tissues that would still show orientation dependence after conventional scalar-based quantitative susceptibility mapping (QSM) to remove such dependence. Similar to diffusion tensor imaging (DTI), STI allows mapping of brain white matter fiber orientations and reconstruction of 3D white matter pathways using the principal eigenvectors of the susceptibility tensor. In contrast to diffusion anisotropy, the main determinant factor of susceptibility anisotropy in brain white matter is myelin. Another unique feature of susceptibility anisotropy of white matter is its sensitivity to gadolinium-based contrast agents. Mechanistically, MRI-observed susceptibility anisotropy is mainly attributed to the highly ordered lipid molecules in myelin sheath. STI provides a consistent interpretation of the dependence of phase and susceptibility on orientation at multiple scales. This article reviews the key experimental findings and physical theories that led to the development of STI, its practical implementations, and its applications for brain research. PMID:27120169
Towards Citizen Co-Created Public Service Apps.
Emaldi, Mikel; Aguilera, Unai; López-de-Ipiña, Diego; Pérez-Velasco, Jorge
2017-06-02
WeLive project's main objective is about transforming the current e-government approach by providing a new paradigm based on a new open model oriented towards the design, production and deployment of public services and mobile apps based on the collaboration of different stakeholders. These stakeholders form the quadruple helix, i.e., citizens, private companies, research institutes and public administrations. Through the application of open innovation, open data and open services paradigms, the framework developed within the WeLive project enables the co-creation of urban apps. In this paper, we extend the description of the WeLive platform presented at , plus the preliminary results of the first pilot phase. The two-phase evaluation methodology designed and the evaluation results of first pilot sub-phase are also presented.
NASA Astrophysics Data System (ADS)
Nohavica, D.; Têminová, J.; Berková, D.; Zagrádková, M.; Kortan, I.; Zelinka, I.; Walachová, I.; Malina, V.
1988-11-01
A modified single-phase liquid phase epitaxy method was developed on the basis of a novel variant of the growth boat. The method was used to grow GaInAsP/InP double heterostructures for lasers emitting at 1.3 and 1.55 μm. The main properties of wide-contact diodes (radiation power and threshold current density) were adopted as the characteristics of the quality of heterostructures characterized by different configurations of active and guiding layers. The quality of the structure was confirmed by the fabrication of laser diodes of the following types: stripe with oxide insulation, clad-ridge waveguide, and double-channel planar buried.
Uniforming information management in Finnish Social Welfare.
Laaksonen, Maarit; Kärki, Jarmo; Ailio, Erja
2012-01-01
This paper describes the phases and methods used in the National project for IT in Social Services in Finland (Tikesos). The main goals of Tikesos were to unify the client information systems in social services, to develop electronic documentation and to produce specifications for nationally organized electronic archive. The method of Enterprise Architecture was largely used in the project.
Armored Force: The Rapid Development of a Uniquely American Force
2010-03-19
tank dominated the Armored Force in 1940. The latest model, the M2A4 , weighed 12 tons and carried a 37mm main gun mounted in a single turret. It also...exploitation phase. Second, armor was concentrated in sufficient mass at the point of the breakthrough. This enabled the armored units to blast their
NASA Technical Reports Server (NTRS)
Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan
2014-01-01
ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.
Edmonds, Stephanie W; Solimeo, Samantha L; Nguyen, Vu-Thuy; Wright, Nicole C; Roblin, Douglas W; Saag, Kenneth G; Cram, Peter
2017-01-01
Context Patient education materials can provide important information related to osteoporosis prevention and treatment. However, available osteoporosis education materials fail to follow best-practice guidelines for patient education. Objective To develop an educational brochure on bone health for adults aged 50 years and older using mixed-method, semistructured interviews. Design This project consisted of 3 phases. In Phase 1, we developed written content that included information about osteoporosis. Additionally, we designed 2 graphic-rich brochures, Brochure A (photographs) and Brochure B (illustrations). In Phase 2, interviewers presented the text-only document and both brochure designs to 53 participants from an academic Medical Center in the Midwest and an outpatient clinic in the Southeastern region of the US. Interviewers used open- and closed-ended questions to elicit opinions regarding the brochures. In Phase 3, using feedback from Phase 2, we revised the brochure and presented it to 11 participants at a third site in the Southeastern US. Main Outcome Measures Participants’ comprehension of brochure text and acceptability of brochure design. Results We enrolled 64 participants. Most were women, white, and college-educated, with an average age of 66.1 years. Participants were able to restate the basic content of the brochure and preferred Brochure A’s use of photographs. Conclusions Using feedback from older adults, we developed and refined a brochure for communicating bone health information to older adults at risk of osteoporosis and fragility fractures. The methods outlined in this article may serve to guide others in developing health educational brochures for chronic medical conditions. PMID:28080957
Semiclassical limit of the focusing NLS: Whitham equations and the Riemann-Hilbert Problem approach
NASA Astrophysics Data System (ADS)
Tovbis, Alexander; El, Gennady A.
2016-10-01
The main goal of this paper is to put together: a) the Whitham theory applicable to slowly modulated N-phase nonlinear wave solutions to the focusing nonlinear Schrödinger (fNLS) equation, and b) the Riemann-Hilbert Problem approach to particular solutions of the fNLS in the semiclassical (small dispersion) limit that develop slowly modulated N-phase nonlinear wave in the process of evolution. Both approaches have their own merits and limitations. Understanding of the interrelations between them could prove beneficial for a broad range of problems involving the semiclassical fNLS.
NASA Small Business Innovation Research Program. Composite List of Projects, 1983 to 1989
NASA Technical Reports Server (NTRS)
1990-01-01
The NASA SBIR Composite List of Projects, 1983 to 1989, includes all projects that have been selected for support by the Small Business Innovation Research (SBIR) Program of NASA. The list describes 1232 Phase 1 and 510 Phase 2 contracts that had been awarded or were in negotiation for award in August 1990. The main body is organized alphabetically by name of the small businesses. Four indexes cross-reference the list. The objective of this listing is to provide information about the SBIR program to anyone concerned with NASA research and development activities.
Campbell, Keri R.; Judge, Elizabeth J.; Barefield, James E.; ...
2017-04-22
We show the analysis of light water reactor simulated used nuclear fuel using laser-induced breakdown spectroscopy (LIBS) is explored using a simplified version of the main oxide phase. The main oxide phase consists of the actinides, lanthanides, and zirconium. The purpose of this study is to develop a rapid, quantitative technique for measuring zirconium in a uranium dioxide matrix without the need to dissolve the material. A second set of materials including cerium oxide is also analyzed to determine precision and limit of detection (LOD) using LIBS in a complex matrix. Two types of samples are used in this study:more » binary and ternary oxide pellets. The ternary oxide, (U,Zr,Ce)O 2 pellets used in this study are a simplified version the main oxide phase of used nuclear fuel. The binary oxides, (U,Ce)O 2 and (U,Zr)O 2 are also examined to determine spectral emission lines for Ce and Zr, potential spectral interferences with uranium and baseline LOD values for Ce and Zr in a UO 2 matrix. In the spectral range of 200 to 800 nm, 33 cerium lines and 25 zirconium lines were identified and shown to have linear correlation values (R 2) > 0.97 for both the binary and ternary oxides. The cerium LOD in the (U,Ce)O 2 matrix ranged from 0.34 to 1.08 wt% and 0.94 to 1.22 wt% in (U,Ce,Zr)O 2 for 33 of Ce emission lines. The zirconium limit of detection in the (U,Zr)O 2 matrix ranged from 0.84 to 1.15 wt% and 0.99 to 1.10 wt% in (U,Ce,Zr)O 2 for 25 Zr lines. Finally, the effect of multiple elements in the plasma and the impact on the LOD is discussed.« less
NASA Astrophysics Data System (ADS)
Tsai, Chun-Wei; Lyu, Bo-Han; Wang, Chen; Hung, Cheng-Chieh
2017-05-01
We have already developed multi-function and easy-to-use modulation software that was based on LabVIEW system. There are mainly four functions in this modulation software, such as computer generated holograms (CGH) generation, CGH reconstruction, image trimming, and special phase distribution. Based on the above development of CGH modulation software, we could enhance the performance of liquid crystal on silicon - spatial light modulator (LCoSSLM) as similar as the diffractive optical element (DOE) and use it on various adaptive optics (AO) applications. Through the development of special phase distribution, we are going to use the LCoS-SLM with CGH modulation software into AO technology, such as optical microscope system. When the LCOS-SLM panel is integrated in an optical microscope system, it could be placed on the illumination path or on the image forming path. However, LCOS-SLM provides a program-controllable liquid crystal array for optical microscope. It dynamically changes the amplitude or phase of light and gives the obvious advantage, "Flexibility", to the system
Contributions of substorm injections to SYM-H depressions in the main phase of storms
NASA Astrophysics Data System (ADS)
He, Zhaohai; Dai, Lei; Wang, Chi; Duan, Suping; Zhang, Lingqian; Chen, Tao; Roth, I.
2016-12-01
Substorm injections bring energetic particles to the inner magnetosphere. But the role of the injected population in building up the storm time ring current is not well understood. By surveying Los Alamos National Laboratory geosynchronous data during 34 storm main phases, we show evidence that at least some substorm injections can contribute to substorm-time scale SYM-H/Dst depressions in the main phase of storms. For event studies, we analyze two typical events in which the main-phase SYM-H index exhibited stepwise depressions that are correlated with particle flux enhancement due to injections and with AL index. A statistical study is performed based on 95 storm time injection events. The flux increases of the injected population (50-400 keV) are found proportional to the sharp SYM-H depressions during the injection interval. By identifying dispersionless and dispersive injection signals, we estimate the azimuthal extent of the substorm injection. Statistical results show that the injection regions of these storm time substorms are characterized with an azimuthal extent larger than 06:00 magnetic local time. These results suggest that at least some substorm injections may mimic the large-scale enhanced convection and contribute to sharp decreases of Dst in the storm main phase.
Liu, Dongming; Li, Mingxiao; Xi, Beidou; Zhao, Yue; Wei, Zimin; Song, Caihong; Zhu, Chaowei
2015-01-01
Composting is an appropriate management alternative for municipal solid waste; however, our knowledge about the microbial regulation of this process is still scare. We employed metaproteomics to elucidate the main biodegradation pathways in municipal solid waste composting system across the main phases in a large-scale composting plant. The investigation of microbial succession revealed that Bacillales, Actinobacteria and Saccharomyces increased significantly with respect to abundance in composting process. The key microbiologic population for cellulose degradation in different composting stages was different. Fungi were found to be the main producers of cellulase in earlier phase. However, the cellulolytic fungal communities were gradually replaced by a purely bacterial one in active phase, which did not support the concept that the thermophilic fungi are active through the thermophilic phase. The effective decomposition of cellulose required the synergy between bacteria and fungi in the curing phase. PMID:25989417
NASA Astrophysics Data System (ADS)
Capuano, Paolo; De Lauro, Enza; De Martino, Salvatore; Falanga, Mariarosaria; Petrosino, Simona
2015-04-01
One of the main challenge in volcano-seismological literature is to locate and characterize the source of volcano/tectonic seismic activity. This passes through the identification at least of the onset of the main phases, i.e. the body waves. Many efforts have been made to solve the problem of a clear separation of P and S phases both from a theoretical point of view and developing numerical algorithms suitable for specific cases (see, e.g., Küperkoch et al., 2012). Recently, a robust automatic procedure has been implemented for extracting the prominent seismic waveforms from continuously recorded signals and thus allowing for picking the main phases. The intuitive notion of maximum non-gaussianity is achieved adopting techniques which involve higher-order statistics in frequency domain., i.e, the Convolutive Independent Component Analysis (CICA). This technique is successful in the case of the blind source separation of convolutive mixtures. In seismological framework, indeed, seismic signals are thought as the convolution of a source function with path, site and the instrument response. In addition, time-delayed versions of the same source exist, due to multipath propagation typically caused by reverberations from some obstacle. In this work, we focus on the Volcano Tectonic (VT) activity at Campi Flegrei Caldera (Italy) during the 2006 ground uplift (Ciaramella et al., 2011). The activity was characterized approximately by 300 low-magnitude VT earthquakes (Md < 2; for the definition of duration magnitude, see Petrosino et al. 2008). Most of them were concentrated in distinct seismic sequences with hypocenters mainly clustered beneath the Solfatara-Accademia area, at depths ranging between 1 and 4 km b.s.l.. The obtained results show the clear separation of P and S phases: the technique not only allows the identification of the S-P time delay giving the timing of both phases but also provides the independent waveforms of the P and S phases. This is an enormous advantage for all the problems related to the source inversion and location In addition, the VT seismicity was accompanied by hundreds of LP events (characterized by spectral peaks in the 0.5-2-Hz frequency band) that were concentrated in a 7-day interval. The main interest is to establish whether the occurrence of LPs is only limited to the swarm that reached a climax on days 26-28 October as indicated by Saccorotti et al. (2007), or a longer period is experienced. The automatically extracted waveforms with improved signal-to-noise ratio via CICA coupled with automatic phase picking allowed to compile a more complete seismic catalog and to better quantify the seismic energy release including the presence of LP events from the beginning of October until mid of November. Finally, a further check of the volcanic nature of extracted signals is achieved by looking at the seismological properties and the content of entropy held in the traces (Falanga and Petrosino 2012; De Lauro et al., 2012). Our results allow us to move towards a full description of the complexity of the source, which can be used for hazard-model development and forecast-model testing, showing an illustrative example of the applicability of the CICA method to regions with low seismicity in high ambient noise
Temperature-Controlled High-Speed AFM: Real-Time Observation of Ripple Phase Transitions.
Takahashi, Hirohide; Miyagi, Atsushi; Redondo-Morata, Lorena; Scheuring, Simon
2016-11-01
With nanometer lateral and Angstrom vertical resolution, atomic force microscopy (AFM) has contributed unique data improving the understanding of lipid bilayers. Lipid bilayers are found in several different temperature-dependent states, termed phases; the main phases are solid and fluid phases. The transition temperature between solid and fluid phases is lipid composition specific. Under certain conditions some lipid bilayers adopt a so-called ripple phase, a structure where solid and fluid phase domains alternate with constant periodicity. Because of its narrow regime of existence and heterogeneity ripple phase and its transition dynamics remain poorly understood. Here, a temperature control device to high-speed atomic force microscopy (HS-AFM) to observe dynamics of phase transition from ripple phase to fluid phase reversibly in real time is developed and integrated. Based on HS-AFM imaging, the phase transition processes from ripple phase to fluid phase and from ripple phase to metastable ripple phase to fluid phase could be reversibly, phenomenologically, and quantitatively studied. The results here show phase transition hysteresis in fast cooling and heating processes, while both melting and condensation occur at 24.15 °C in quasi-steady state situation. A second metastable ripple phase with larger periodicity is formed at the ripple phase to fluid phase transition when the buffer contains Ca 2+ . The presented temperature-controlled HS-AFM is a new unique experimental system to observe dynamics of temperature-sensitive processes at the nanoscopic level. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Bian, Lu-peng; Li, Ying; Han, Xu-hao; Cheng, Jin-yun; Qin, Xiao-ning; Zhao, Yan-qiu; Sun, Ji-bing
2018-02-01
New SmCo5 + x wt% Alnico composite ribbons melt-spun at 40 m/s are designed by multi-element addition of Alnico alloy into SmCo5 matrix, and their structure and magnetic properties are investigated. The results show that the main phase in x ≤ 2.5 ribbons is Sm(Co,M)5, whereas the main phase changes into Sm(Co,M)7 at x = 4.0-8.5, and simultaneously that the content of Al-rich and amorphous phases increases with increasing x. The hard magnetic properties of the ribbons are found to improve with an increase in Alnico content, and particularly the average magnetic properties reach maximum, i.e., Hc = 19.6 ± 1.2 kOe, Mr = 47.7 ± 3.4 emu/g and M2T = 59.1 ± 5.6 emu/g, at x = 4.0. The main reasons for such improvement are that the finer grains divided by three grain boundaries exist in main phase, the dispersed Al-Ni and Al-Co-rich phases distribute in grains and grain boundaries, and the Fe-rich Alnico alloying elements dissolve into Sm(Co,M)7 matrix phase. However, when x > 4.0, the gradually increasing Al-Co and amorphous phases lead to the reduction of hard magnetic properties.
Coupled Structural, Thermal, Phase-Change and Electromagnetic Analysis for Superconductors. Volume 1
NASA Technical Reports Server (NTRS)
Felippa, C. A.; Farhat, C.; Park, K. C.; Militello, C.; Schuler, J. J.
1996-01-01
Described are the theoretical development and computer implementation of reliable and efficient methods for the analysis of coupled mechanical problems that involve the interaction of mechanical, thermal, phase-change and electromagnetic subproblems. The focus application has been the modeling of superconductivity and associated quantum-state phase-change phenomena. In support of this objective the work has addressed the following issues: (1) development of variational principles for finite elements, (2) finite element modeling of the electromagnetic problem, (3) coupling of thermal and mechanical effects, and (4) computer implementation and solution of the superconductivity transition problem. The main accomplishments have been: (1) the development of the theory of parametrized and gauged variational principles, (2) the application of those principled to the construction of electromagnetic, thermal and mechanical finite elements, and (3) the coupling of electromagnetic finite elements with thermal and superconducting effects, and (4) the first detailed finite element simulations of bulk superconductors, in particular the Meissner effect and the nature of the normal conducting boundary layer. The theoretical development is described in two volumes. This volume, Volume 1, describes mostly formulations for specific problems. Volume 2 describes generalization of those formulations.
Analyzing global trends of biomarker use in drug interventional clinical studies.
Hayashi, K; Masuda, S; Kimura, H
2012-04-01
The trend of biomarker use in drug interventional clinical studies was analyzed using ClinicalTrials.gov to provide an overview of how biomarkers are used to streamline clinical studies and to examine regional differences. A total of 3,383 clinical study data was analyzed according to phase, region, sponsor, and therapeutic class. The number of clinical studies using biomarkers has been increasing constantly and is dependent on the number of Phase I and II studies. The majority of studies (58.5%) were sponsored by the United States, with the studies being conducted mainly in the sponsor's home region (80.3%). The use of biomarkers was prominent in the oncology area (37.1%). Although current data indicates some bias in the clinical use of biomarkers, it is expected that their use will increase in later phase studies or other therapeutic areas as biomarker development proceeds. In addition, limited regional use of biomarkers may lead to differences in biomarker use in drug development and in combination with political support may result in differences in competitiveness of drug development. Biomarkers would be a powerful tool against deteriorating research and development productivity when used more in appropriate clinical study conditions.
[Concepts in anticoagulant therapy - past, present, and future].
Graf, L
2012-11-01
The understanding of the clotting system emerged in parallel to the development of anticoagulants. In contrast to vitamin K-antagonists and heparins that where discovered by chance, new anticoagulants have been systematically designed to specifically inhibit single clotting factors. Both clotting factors Xa (FXa) and thrombin play a crucial role within the new cell-based model of hemostasis. Thus it is obvious that FXa and thrombin turned out to be ideal targets for anticoagulation. The proof of the concept of selective inhibition of thrombin and FXa has been provided by hirudin and fondaparinux, respectively. By now, a whole group of new oral anticoagulants has been licensed: the direct FXa-inhibitors rivaroxaban, apixaban, and edoxaban as well as the direct thrombin dabigatran etexilate. Furthermore, a bundle of FXa- and thrombin-inhibitors that differ from the so far licensed products mainly in pharmacokinetics are in an advanced phase of development. A further innovative concept of anticoagulation that entered its clinical phase of development is the inhibition of factor VIII. Other new concepts such as inhibition of initiation of coagulation by blocking factor VIIa, inhibition of contact factor XII, or inhibition of factor IX are in an early phase of development.
Which emotional regulatory strategy makes Chinese adolescents happier? A longitudinal study.
Sang, Biao; Deng, Xinmei; Luan, Ziyan
2014-12-01
Growing interest in emotion regulation is reflected in the studies of cognitive and social development. However, the extant studies mainly highlight how emotion regulation develops based on a western value system. This study utilised a longitudinal design to examine the development of emotion regulation and explored the contributions of different regulatory strategies to emotion experience regarding the early adolescent development period in a Chinese population. A total of 303 Chinese adolescents (age range = 10-14 years) were followed up in a three-phase longitudinal study for 3 years. In each phase of the study, participants completed Adolescents Emotion Regulation Questionnaire and Daily Emotion Scale. Results of hierarchical linear regressions revealed that Chinese adolescents reported more down-regulation. Down-regulation is more effective than up-regulation in enhancing desirable emotion experience and reducing undesirable emotion experience during adolescents' development. Also, the adaptive functions of emotional regulatory strategies in Chinese background were discussed. © 2014 International Union of Psychological Science.
NASA Astrophysics Data System (ADS)
Hidayati, A.; Rahmi, A.; Yohandri; Ratnawulan
2018-04-01
The importance of teaching materials in accordance with the characteristics of students became the main reason for the development of basic electronics I module integrated character values based on conceptual change teaching model. The module development in this research follows the development procedure of Plomp which includes preliminary research, prototyping phase and assessment phase. In the first year of this research, the module is validated. Content validity is seen from the conformity of the module with the development theory in accordance with the demands of learning model characteristics. The validity of the construct is seen from the linkage and consistency of each module component developed with the characteristic of the integrated learning model of character values obtained through validator assessment. The average validation value assessed by the validator belongs to a very valid category. Based on the validator assessment then revised the basic electronics I module integrated character values based on conceptual change teaching model.
Vaccination Against Dengue: Challenges and Current Developments.
Guy, Bruno; Lang, Jean; Saville, Melanie; Jackson, Nicholas
2016-01-01
Dengue is a growing threat worldwide, and the development of a vaccine is a public health priority. The completion of the active phase of two pivotal efficacy studies conducted in Asia and Latin America by Sanofi Pasteur has constituted an important step. Several other approaches are under development, and whichever technology is used, vaccine developers face several challenges linked to the particular nature and etiology of dengue disease. We start our review by defining questions and potential issues linked to dengue pathology and presenting the main types of vaccine approaches that have explored these questions; some of these candidates are in a late stage of clinical development. In the second part of the review, we focus on the Sanofi Pasteur dengue vaccine candidate, describing the steps from research to phase III efficacy studies. Finally, we discuss what could be the next steps, before and after vaccine introduction, to ensure that the vaccine will provide the best benefit with an acceptable safety profile to the identified target populations.
Ka-Band Multibeam Aperture Phased Array Being Developed
NASA Technical Reports Server (NTRS)
Reinhart, Richard C.; Kacpura, Thomas J.
2004-01-01
Phased-array antenna systems offer many advantages to low-Earth-orbiting satellite systems. Their large scan angles and multibeam capabilities allow for vibration-free, rapid beam scanning and graceful degradation operation for high rate downlink of data to users on the ground. Technology advancements continue to reduce the power, weight, and cost of these systems to make phased arrays a competitive alternative in comparison to the gimbled reflector system commonly used in science missions. One effort to reduce the cost of phased arrays is the development of a Ka-band multibeam aperture (MBA) phased array by Boeing Corporation under a contract jointly by the NASA Glenn Research Center and the Office of Naval Research. The objective is to develop and demonstrate a space-qualifiable dual-beam Ka-band (26.5-GHz) phased-array antenna. The goals are to advance the state of the art in Ka-band active phased-array antennas and to develop and demonstrate multibeam transmission technology compatible with spacecraft in low Earth orbit to reduce the cost of future missions by retiring certain development risks. The frequency chosen is suitable for space-to-space and space-to-ground communication links. The phased-array antenna has a radiation pattern designed by combining a set of individual radiating elements, optimized with the type of radiating elements used, their positions in space, and the amplitude and phase of the currents feeding the elements. This arrangement produces a directional radiation pattern that is proportional to the number of individual radiating elements. The arrays of interest here can scan the main beam electronically with a computerized algorithm. The antenna is constructed using electronic components with no mechanical parts, and the steering is performed electronically, without any resulting vibration. The speed of the scanning is limited primarily by the control electronics. The radiation performance degrades gracefully if a portion of the elements fail. The arrays can be constructed to conform to a mounting surface, and multibeam capability is integral to the design. However, there are challenges for mission designers using monolithic-microwave-integrated-circuit- (MMIC-) based arrays because of reduced power efficiency, higher costs, and certain system effects that result in link degradations. The multibeam aperture phased-array antenna development is attempting to address some of these issues, particularly manufacturing, costs, and system performance.
Preparative crystallization of a single chain antibody using an aqueous two-phase system.
Huettmann, Hauke; Berkemeyer, Matthias; Buchinger, Wolfgang; Jungbauer, Alois
2014-11-01
A simultaneous crystallization and aqueous two-phase extraction of a single chain antibody was developed, demonstrating process integration. The process conditions were designed to form an aqueous two-phase system, and to favor crystallization, using sodium sulfate and PEG-2000. At sufficiently high concentrations of PEG, a second phase was generated in which the protein crystallization occurred simultaneously. The single chain antibody crystals were partitioned to the top, polyethylene glycol-rich phase. The crystal nucleation took place in the sodium sulfate-rich phase and at the phase boundary, whereas crystal growth was progressing mainly in the polyethylene glycol-rich phase. The crystals in the polyethylene glycol-rich phase grew to a size of >50 µm. Additionally, polyethylene glycol acted as an anti-solvent, thus, it influenced the crystallization yield. A phase diagram with an undersaturation zone, crystallization area, and amorphous precipitation zone was established. Only small differences in polyethylene glycol concentration caused significant shifts of the crystallization yield. An increase of the polyethylene glycol content from 2% (w/v) to 4% (w/v) increased the yield from approximately 63-87%, respectively. Our results show that crystallization in aqueous two-phase systems is an opportunity to foster process integration. © 2014 Wiley Periodicals, Inc.
Phase-insensitive storage of coherences by reversible mapping onto long-lived populations
NASA Astrophysics Data System (ADS)
Mieth, Simon; Genov, Genko T.; Yatsenko, Leonid P.; Vitanov, Nikolay V.; Halfmann, Thomas
2016-01-01
We theoretically develop and experimentally demonstrate a coherence population mapping (CPM) protocol to store atomic coherences in long-lived populations, enabling storage times far beyond the typically very short decoherence times of quantum systems. The amplitude and phase of an atomic coherence is written onto the populations of a three-state system by specifically designed sequences of radiation pulses from two coupling fields. As an important feature, the CPM sequences enable a retrieval efficiency, which is insensitive to the phase of the initial coherence. The information is preserved in every individual atom of the medium, enabling applications in purely homogeneously or inhomogeneously broadened ensembles even when stochastic phase jumps are the main source of decoherence. We experimentally confirm the theoretical predictions by applying CPM for storage of atomic coherences in a doped solid, reaching storage times in the regime of 1 min.
NASA Astrophysics Data System (ADS)
Quesnel, François; Soucy, Gervais; Veilleux, Jocelyn; Hovington, Pierre; Zhu, Wen; Zaghib, Karim
The properties of lithium titanates anodes in Li-ion batteries are highly dependent on their secondary constituents. While their main phase is usually constituted of Li4Ti5O12, significant quantity of lithium titanates compounds of various stoichiometry are often present, due to either the processing, usage or aging of the material. These may go underreported, as many of these spectrums overlap or display low signal in X-ray diffraction (XRD). Samples of nanosized lithium titanates synthetized by inductive plasma were characterized by XRD and scanning electron microscopy (SEM), as they provide a regular yet typical crystallite size and shape including multiple phases. A Rietveld refinement was developed to extract the composition of these samples. Mass balance through further annealing and differential scanning calorimetry (DSC) enthalpy measurements from phase transformations were also used as identification and validation techniques.
NASA Astrophysics Data System (ADS)
Yasuoka, Shigekazu; Ishida, Jun; Kishida, Kyosuke; Inui, Haruyuki
2017-04-01
The influence of Ce addition on the phase constitution, microstructure, hydrogen absorption/desorption properties and battery performances of newly developed rare earth (RE)-Mg-Ni hydrogen-absorbing superlattice alloys for negative electrode materials in Ni-metal hydride (MH) batteries were investigated. The partial substitution of RE (La and Nd) with Ce results in a higher discharge performance and a lower cycle life in the battery. The Ce addition greatly affects the phase constitution, which is mainly characterized by increased formation of the AB2 phase (A = RE or Mg and B = Ni or Al). The existence of the AB2 phase is found to accelerate alloy pulverization and oxidation when the alloys are used as negative electrode materials in Ni-MH model cells. The accelerated pulverization and oxidation are considered to be responsible for the observed higher discharge performance and lower cycle life in the batteries, respectively.
Nutritional and metabolic programming during the first thousand days of life.
Agosti, Massimo; Tandoi, Francesco; Morlacchi, Laura; Bossi, Angela
2017-06-28
The latest scientific acquisitions are demonstrating what has already been hypothesized for more than twenty years about the development of the state of health/illness of individuals. Indeed, certain stimuli, if applied to a sensible phase of development, are able to modify, through epigenetic mechanisms, gene expression of DNA, resulting in adaptive modifications of phenotype to the environment, which may reflect negatively on the health of every individual. This concept, applied to nutrition, has opened up important prospects for research in this area. The nutritional history of an individual, linked to the development of a healthy state, would begin very early. In fact, since the pregnancy and for the next two years (for a total of about 1000 days), the maternal eating habits, the type of breastfeeding and then the main stages of nutrition in the evolutionary phase represent those sensitive moments, essential for the development of important endocrine, metabolic, immunological alterations, better known as metabolic syndrome. This condition would represent the physiopathogenetic basis for explaining a series of disorders, known as non communicable diseases (NCDs) such as obesity, diabetes, hypertension, cardiovascolar disease and all those conditions that today affect the health of most industrialized countries and through the years are emerging especially in developing countries (South America, Asia), where new environmental conditions and increased food availability are changing food habits, with far-reaching public health impacts. This paper analyzes these new nutritional perspectives and the main implications of what has been termed the 1000-day theory.
NASA Astrophysics Data System (ADS)
Kuntoro, Hadiyan Yusuf; Hudaya, Akhmad Zidni; Dinaryanto, Okto; Majid, Akmal Irfan; Deendarlianto
2016-06-01
Due to the importance of the two-phase flow researches for the industrial safety analysis, many researchers developed various methods and techniques to study the two-phase flow phenomena on the industrial cases, such as in the chemical, petroleum and nuclear industries cases. One of the developing methods and techniques is image processing technique. This technique is widely used in the two-phase flow researches due to the non-intrusive capability to process a lot of visualization data which are contain many complexities. Moreover, this technique allows to capture direct-visual information data of the flow which are difficult to be captured by other methods and techniques. The main objective of this paper is to present an improved algorithm of image processing technique from the preceding algorithm for the stratified flow cases. The present algorithm can measure the film thickness (hL) of stratified flow as well as the geometrical properties of the interfacial waves with lower processing time and random-access memory (RAM) usage than the preceding algorithm. Also, the measurement results are aimed to develop a high quality database of stratified flow which is scanty. In the present work, the measurement results had a satisfactory agreement with the previous works.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuntoro, Hadiyan Yusuf, E-mail: hadiyan.y.kuntoro@mail.ugm.ac.id; Majid, Akmal Irfan; Deendarlianto, E-mail: deendarlianto@ugm.ac.id
Due to the importance of the two-phase flow researches for the industrial safety analysis, many researchers developed various methods and techniques to study the two-phase flow phenomena on the industrial cases, such as in the chemical, petroleum and nuclear industries cases. One of the developing methods and techniques is image processing technique. This technique is widely used in the two-phase flow researches due to the non-intrusive capability to process a lot of visualization data which are contain many complexities. Moreover, this technique allows to capture direct-visual information data of the flow which are difficult to be captured by other methodsmore » and techniques. The main objective of this paper is to present an improved algorithm of image processing technique from the preceding algorithm for the stratified flow cases. The present algorithm can measure the film thickness (h{sub L}) of stratified flow as well as the geometrical properties of the interfacial waves with lower processing time and random-access memory (RAM) usage than the preceding algorithm. Also, the measurement results are aimed to develop a high quality database of stratified flow which is scanty. In the present work, the measurement results had a satisfactory agreement with the previous works.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Almansouri, Hani; Foster, Benjamin; Kisner, Roger A
2016-01-01
This paper documents our progress developing an ultrasound phased array system in combination with a model-based iterative reconstruction (MBIR) algorithm to inspect the health of and characterize the composition of the near-wellbore region for geothermal reservoirs. The main goal for this system is to provide a near-wellbore in-situ characterization capability that will significantly improve wellbore integrity evaluation and near well-bore fracture network mapping. A more detailed image of the fracture network near the wellbore in particular will enable the selection of optimal locations for stimulation along the wellbore, provide critical data that can be used to improve stimulation design, andmore » provide a means for measuring evolution of the fracture network to support long term management of reservoir operations. Development of such a measurement capability supports current hydrothermal operations as well as the successful demonstration of Engineered Geothermal Systems (EGS). The paper will include the design of the phased array system, the performance specifications, and characterization methodology. In addition, we will describe the MBIR forward model derived for the phased array system and the propagation of compressional waves through a pseudo-homogenous medium.« less
1980-09-01
insurance costs, a decrease in available low-income housing which tends to cluster around the river, increase in the cost of existing housing (from...developable lands is thus a real loss, not merely a paper loss of unquantifiable "potential." The relocation of the established residential community, a...habitat largely vegetation types somewhat, due tolarge dom releasNS. Least Bell’s virgo No change. 1,OOD-acre Prado borrow 440 acres of borrow Mo change
Galileo Parachute System modification program
NASA Technical Reports Server (NTRS)
Mcmenamin, H. J.; Pochettino, L. R.
1984-01-01
This paper discusses the development program conducted on the Galileo Parachute System following the slow opening performance of the main parachute during the first system drop test. The parachute system is part of the Galileo entry probe that will descend through the Jupiter atmosphere. The uncontrolled parachute opening experienced in this test was not acceptable for the probe system. Therefore, the main parachute design was modified and the system sequence was changed to prevent a recurrence. These alterations and their system effects were evaluated analytically, and in a ground test program. At the conclusion of this phase, the system drop test was successfully repeated.
New developments for determination of uncertainty in phase evaluation
NASA Astrophysics Data System (ADS)
Liu, Sheng
Phase evaluation exists mostly in, but not limited to, interferometric applications that utilize coherent multidimensional signals to modulate the physical quantity of interest into a nonlinear form, represented by repeating the phase modulo of 271 radians. In order to estimate the underlying physical quantity, the wrapped phase has to be unwrapped by an evaluation procedure which is usually called phase unwrapping. The procedure of phase unwrapping will obviously face the challenge of inconsistent phase, which could bring errors in phase evaluation. The main objectives of this research include addressing the problem of inconsistent phase in phase unwrapping and applications in modern optical techniques. In this research, a new phase unwrapping algorithm is developed. The creative idea of doing phase unwrapping between regions has an advantage over conventional pixel-to-pixel unwrapping methods because the unwrapping result is more consistent by using a voting mechanism based on all Zit-discontinuities hints. Furthermore, a systematic sequence of regional unwrapping is constructed in order to achieve a global consistent result. An implementation of the idea is illustrated in dct.il with step-by-step pseudo codes. The performance of the algorithm is demonstrated on real world applications. In order to solve a phase unwrapping problem which is caused by depth discontinuities in 3D shape measurement, a new absolute phase coding strategy is developed. The algorithm presented has two merits: effectively extends the coding range and preserves the measurement sensitivity. The performance of the proposed absolute coding strategy is proved by results of 3D shape measurement for objects with surface discontinuities. As a powerful tool for real world applications a universal software package, Optical Measurement and Evaluation Software (OMES), is designed for the purposes of automatic measurement and quantitative evaluation in 3D shape measurement and laser interferometry. Combined with different sensors or setups, OMES has been successfully applied in the industries, for example, GM Powertrain, Coming, and Ford Optical Lab., and used for various applications such as shape measurement, deformation/displacement measurement, strain/stress analysis, non-destructive testing, vibration/modal analysis, and biomechanics analysis.
An Analytical-Numerical Model for Two-Phase Slug Flow through a Sudden Area Change in Microchannels
Momen, A. Mehdizadeh; Sherif, S. A.; Lear, W. E.
2016-01-01
In this article, two new analytical models have been developed to calculate two-phase slug flow pressure drop in microchannels through a sudden contraction. Even though many studies have been reported on two-phase flow in microchannels, considerable discrepancies still exist, mainly due to the difficulties in experimental setup and measurements. Numerical simulations were performed to support the new analytical models and to explore in more detail the physics of the flow in microchannels with a sudden contraction. Both analytical and numerical results were compared to the available experimental data and other empirical correlations. Results show that models, which were developed basedmore » on the slug and semi-slug assumptions, agree well with experiments in microchannels. Moreover, in contrast to the previous empirical correlations which were tuned for a specific geometry, the new analytical models are capable of taking geometrical parameters as well as flow conditions into account.« less
Computer-aided evaluation of the railway track geometry on the basis of satellite measurements
NASA Astrophysics Data System (ADS)
Specht, Cezary; Koc, Władysław; Chrostowski, Piotr
2016-05-01
In recent years, all over the world there has been a period of intensive development of GNSS (Global Navigation Satellite Systems) measurement techniques and their extension for the purpose of their applications in the field of surveying and navigation. Moreover, in many countries a rising trend in the development of rail transportation systems has been noticed. In this paper, a method of railway track geometry assessment based on mobile satellite measurements is presented. The paper shows the implementation effects of satellite surveying railway geometry. The investigation process described in the paper is divided on two phases. The first phase is the GNSS mobile surveying and the analysis obtained data. The second phase is the analysis of the track geometry using the flat coordinates from the surveying. The visualization of the measured route, separation and quality assessment of the uniform geometric elements (straight sections, arcs), identification of the track polygon (main directions and intersection angles) are discussed and illustrated by the calculation example within the article.
Effect of pre-strain on precipitation and exfoliation corrosion resistance in an Al-Zn-Mg alloy
NASA Astrophysics Data System (ADS)
Lu, Xianghan; Du, Zhiwei; Han, Xiaolei; Li, Ting; Wang, Guojun; Lu, Liying; Bai, Xiaoxia; Zhou, Tietao
2017-12-01
To investigate the effect of pre-strain on behaviors in a specially developed Al-4.5Zn-1.2Mg alloy, transmission electron microscopy (TEM) bright field (BF) imaging combined with select area electron diffraction (SAED), Vickers-hardness tests and electrical conductivity tests was conducted for insight into precipitation in aluminum (Al) matrix during two step ageing, and standard exfoliation corrosion (EXCO) test combined with high-angle angular dark field scanning transmission electron microscopy (HAADF-STEM) and scanning electron microscopy (SEM) was carried out for corrosion behavior. Results showed that pre-strain accelerated precipitation during two step ageing as the sequence of: (i) supersaturated solid solution (SSS), GPI zones precipitations, GPI dissolution; (ii) SSS, fcc precipitates, η’ phases or η phases. And the precipitation hardening of the fcc precipitates was not effective as GPI zones. Pre-strain also accelerated EXCO developing, which was mainly attributed to the coverage ratio of η phases on high-angle grain boundaries (HAGBs) increasing as pre-strain increase.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheung, Michael L M; Chan, Anthony T C; The Chinese University of Hong Kong
Purpose: To develop a formulation for 4D treatment planning for a tumour tracking volumetric modulated arc therapy treatment (VMAT) plan for lung cancer. Methods: A VMAT plan was optimized based on a reference phase of the 4DCT of a lung cancer patient. The PTV was generated from the GTV of the reference phase. The collimator angle was set to 90 degrees such that the MLC travels along superior-inferior direction which is the main component of movement of a lung tumour. Then, each control point of the VMAT plan was assigned to a particular phase of the 4DCT in chronological order.more » The MLC positions of each control point were shifted according to the position of the tumour centroid of its assigned phase to form a tumour tracking VMAT plan. The control points of the same phase were grouped to form a pseudo VMAT plan for that particular phase. Dose calculation was performed for each pseudo VMAT plan on the corresponding phase of the 4DCT. The CTs of all phases were registered to the reference phase CT according to the displacement of the tumour centroid. The individual dose distributions of the pseudo VMAT plans were summed up and displayed on the reference phase of the 4DCT. A control VMAT plan was optimized based on a PTV generated from the ITV of all phases and compared with the tumour tracking VMAT plan. Results: Both plans achieved >95% volume coverage at the prescription dose level (96% for the tumour tracking plan and 97% for the control plan). But the normal lung volume irradiated at the prescription dose level was 39% less for the tumour tracking plan than the control plan. Conclusion: A formulation of 4D treatment planning for tumour tracking VMAT plans for lung cancer was developed.« less
Cell Cycle Deregulation in the Neurons of Alzheimer’s Disease
Moh, Calvin; Kubiak, Jacek Z.; Bajic, Vladan P.; Zhu, Xiongwei; Smith, Mark A.
2018-01-01
The cell cycle consists of four main phases: G1, S, G2, and M. Most cells undergo these cycles up to 40–60 times in their life. However, neurons remain in a nondividing, nonreplicating phase, G0. Neurons initiate but do not complete cell division, eventually entering apoptosis. Research has suggested that like cancer, Alzheimer’s disease (AD) involves dysfunction in neuronal cell cycle reentry, leading to the development of the two-hit hypothesis of AD. The first hit is abnormal cell cycle reentry, which typically results in neuronal apoptosis and prevention of AD. However, with the second hit of chronic oxidative damage preventing apoptosis, neurons gain “immortality” analogous to tumor cells. Once both of these hits are activated, AD can develop and produce senile plaques and neurofibrillary tangles throughout brain tissue. In this review, we propose a mechanism for neuronal cell cycle reentry and the development of AD. PMID:21630160
Domene, Xavier; Alcañiz, Josep M; Andrés, Pilar
2008-02-01
Development of methodologies to assess the safety of reusing polluted organic wastes in soil is a priority in Europe. In this study, and coupled with chemical analysis, seven organic wastes were subjected to different aquatic and soil bioassays. Tests were carried out with solid-phase waste and three different waste eluates (water, methanol, and dichloromethane). Solid-phase assays were indicated as the most suitable for waste testing not only in terms of relevance for real situations, but also because toxicity in eluates was generally not representative of the chronic effects in solid-phase. No general correlations were found between toxicity and waste pollutant burden, neither in solid-phase nor in eluate assays, showing the inability of chemical methods to predict the ecotoxicological risks of wastes. On the contrary, several physicochemical parameters reflecting the degree of low organic matter stability in wastes were the main contributors to the acute toxicity seen in collembolans and daphnids.
Design and Stability of an On-Orbit Attitude Control System Using Reaction Control Thrusters
NASA Technical Reports Server (NTRS)
Hall, Robert A.; Hough, Steven; Orphee, Carolina; Clements, Keith
2015-01-01
Principles for the design and stability of a spacecraft on-orbit attitude control system employing on-off Reaction Control System (RCS) thrusters is presented. Both the vehicle dynamics and the control system actuators are inherently nonlinear, hence traditional linear control system design approaches are not directly applicable. This paper has three main aspects: It summarizes key RCS control System design principles from the Space Shuttle and Space Station programs, it demonstrates a new approach to develop a linear model of a phase plane control system using describing functions, and applies each of these to the initial development of the NASA's next generation of upper stage vehicles. Topics addressed include thruster hardware specifications, phase plane design and stability, jet selection approaches, filter design metrics, and automaneuver logic.
NASA Collaborative Design Processes
NASA Technical Reports Server (NTRS)
Jones, Davey
2017-01-01
This is Block 1, the first evolution of the world's most powerful and versatile rocket, the Space Launch System, built to return humans to the area around the moon. Eventually, larger and even more powerful and capable configurations will take astronauts and cargo to Mars. On the sides of the rocket are the twin solid rocket boosters that provide more than 75 percent during liftoff and burn for about two minutes, after which they are jettisoned, lightening the load for the rest of the space flight. Four RS-25 main engines provide thrust for the first stage of the rocket. These are the world's most reliable rocket engines. The core stage is the main body of the rocket and houses the fuel for the RS-25 engines, liquid hydrogen and liquid oxygen, and the avionics, or "brain" of the rocket. The core stage is all new and being manufactured at NASA's "rocket factory," Michoud Assembly Facility near New Orleans. The Launch Vehicle Stage Adapter, or LVSA, connects the core stage to the Interim Cryogenic Propulsion Stage. The Interim Cryogenic Propulsion Stage, or ICPS, uses one RL-10 rocket engine and will propel the Orion spacecraft on its deep-space journey after first-stage separation. Finally, the Orion human-rated spacecraft sits atop the massive Saturn V-sized launch vehicle. Managed out of Johnson Space Center in Houston, Orion is the first spacecraft in history capable of taking humans to multiple destinations within deep space. 2) Each element of the SLS utilizes collaborative design processes to achieve the incredible goal of sending human into deep space. Early phases are focused on feasibility and requirements development. Later phases are focused on detailed design, testing, and operations. There are 4 basic phases typically found in each phase of development.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Zhien
2010-06-29
The project is mainly focused on the characterization of cloud macrophysical and microphysical properties, especially for mixed-phased clouds and middle level ice clouds by combining radar, lidar, and radiometer measurements available from the ACRF sites. First, an advanced mixed-phase cloud retrieval algorithm will be developed to cover all mixed-phase clouds observed at the ACRF NSA site. The algorithm will be applied to the ACRF NSA observations to generate a long-term arctic mixed-phase cloud product for model validations and arctic mixed-phase cloud processes studies. To improve the representation of arctic mixed-phase clouds in GCMs, an advanced understanding of mixed-phase cloud processesmore » is needed. By combining retrieved mixed-phase cloud microphysical properties with in situ data and large-scale meteorological data, the project aim to better understand the generations of ice crystals in supercooled water clouds, the maintenance mechanisms of the arctic mixed-phase clouds, and their connections with large-scale dynamics. The project will try to develop a new retrieval algorithm to study more complex mixed-phase clouds observed at the ACRF SGP site. Compared with optically thin ice clouds, optically thick middle level ice clouds are less studied because of limited available tools. The project will develop a new two wavelength radar technique for optically thick ice cloud study at SGP site by combining the MMCR with the W-band radar measurements. With this new algorithm, the SGP site will have a better capability to study all ice clouds. Another area of the proposal is to generate long-term cloud type classification product for the multiple ACRF sites. The cloud type classification product will not only facilitates the generation of the integrated cloud product by applying different retrieval algorithms to different types of clouds operationally, but will also support other research to better understand cloud properties and to validate model simulations. The ultimate goal is to improve our cloud classification algorithm into a VAP.« less
Cell cycle gene expression under clinorotation
NASA Astrophysics Data System (ADS)
Artemenko, Olga
2016-07-01
Cyclins and cyclin-dependent kinase (CDK) are main regulators of the cell cycle of eukaryotes. It's assumes a significant change of their level in cells under microgravity conditions and by other physical factors actions. The clinorotation use enables to determine the influence of gravity on simulated events in the cell during the cell cycle - exit from the state of quiet stage and promotion presynthetic phase (G1) and DNA synthesis phase (S) of the cell cycle. For the clinorotation effect study on cell proliferation activity is the necessary studies of molecular mechanisms of cell cycle regulation and development of plants under altered gravity condition. The activity of cyclin D, which is responsible for the events of the cell cycle in presynthetic phase can be controlled by the action of endogenous as well as exogenous factors, but clinorotation is one of the factors that influence on genes expression that regulate the cell cycle.These data can be used as a model for further research of cyclin - CDK complex for study of molecular mechanisms regulation of growth and proliferation. In this investigation we tried to summarize and analyze known literature and own data we obtained relatively the main regulators of the cell cycle in altered gravity condition.
Polychaetes of an artificial reef in the central mediterranean sea
NASA Astrophysics Data System (ADS)
Gravina, M. F.; Ardizzone, G. D.; Belluscio, A.
1989-02-01
The development of a polychaete community over five years on a man-made reef was analyzed. The reef was composed of 280 concrete blocks (2 × 2 × 2 m) and located in the Tyrrhenian Sea (Italy) 1.5 miles offshore and 12-14 m deep. Sixty-three species were collected—serpulids, nereids and cirratulids being the most abundant families. Ordination by Principal Components Analysis (PCA) technique showed three main stages in the colonization process: a pioneer phase, when mainly serpulids ( Pomatoceros triqueter, P. lamarckii, Hydroides pseuduncinata) occurred; a second phase, characterized by mussel ( Mytilus galloprovincialis) dominance and a more differentiated community structure with a lot of new species especially recurring on hard bottom ( Serpula concharum, H. dianthus, Ceratonereis costae); and a third phase, with an alteration of the substratum through soft deposits and the polychaete community characterized by also the occurrence of soft bottom species ( Heteromastus filiformis, Polydora ciliata, Dorvillea rubrovittata). From the trophic point of view, the structure of the community changed from dominance by filter feeders (97%) to a more differentiated situation with abundant detritic feeders ( c. 20%). The rates of immigration and extinction and the colonization curve showed that an actual stable steady-state was not reached.
Supporting Indigenous Students' Understanding of the Numeration System of Their First Language
ERIC Educational Resources Information Center
Cortina, Jose Luis
2013-01-01
Results from a project conducted in Mexico are discussed, in which a group of 17 indigenous teachers analyzed the numeration systems of their first language. The main goal of the project is to develop resources that help teachers in supporting students' understanding of the systems. In the first phase of the project, the central organizing ideas…
The report describes the implementation, theory of operation, and performance of an adjustable, 48 tap, surface wave transversal equalizer designed...for the Rome Air Development Center, Floyd Site Radar. The transversal equalizer achieves equalization of system distortion by an array of fixed taps...which provide leading and lagging echoes of the main signal. Equalization is achieved by the introduction of an equal but oppositely phased echo of
Seasonal and diurnal variation in concentrations of gaseous and particulate phase endosulfan
NASA Astrophysics Data System (ADS)
Li, Qingbo; Wang, Xianyu; Song, Jing; Sui, Hongqi; Huang, Lei; Li, Lu
2012-12-01
Successive 52-week air monitoring of α-endosulfan (α-E), β-endosulfan (β-E) and endosulfan sulfate (E.S) in the gaseous and particulate phases was conducted in Dalian city, northeast China by using an active high-volume sampler. Significant seasonal and diurnal variations in endosulfan concentrations were observed. It was found that the concentration of gaseous-phase α-E peaked in the summer and the concentration of particulate phase α-E peaked in the winter. For E.S, both gaseous and particulate phase concentrations peaked in the summer. α-E was distributed predominantly in the gas phase in the summer but was distributed mainly in the particulate phase in the winter. β-E was distributed mainly in the gas phase in the summer and in the particulate phase at other times of the year. E.S was distributed mainly in the particulate phase throughout the year. Elevated temperatures facilitated the volatilization of α-E from particle surfaces but exerted little effect on β-E and had almost no effect on E.S. Trajectory-based analysis indicates that the seasonal variation in atmospheric concentrations of endosulfan in Dalian city was influenced strongly by the land and sea air masses. In addition, differences in endosulfan concentrations in the particulate phase between day and night were likely due to the circulation of sea/land breezes. The 'cold-condensation' effect occurring during the night may result in the attachment of endosulfan to the particulate phase.
Kimiskidis, Vasilios; Spanakis, Marios; Niopas, Ioannis; Kazis, Dimitrios; Gabrieli, Chrysi; Kanaze, Feras Imad; Divanoglou, Daniil
2007-01-17
An isocratic reversed-phase HPLC-UV procedure for the determination of oxcarbazepine and its main metabolites 10-hydroxy-10,11-dihydrocarbamazepine and 10,11-dihydroxy-trans-10,11-dihydrocarbamazepine in human plasma and cerebrospinal fluid has been developed and validated. After addition of bromazepam as internal standard, the analytes were isolated from plasma and cerebrospinal fluid by liquid-liquid extraction. Separation was achieved on a X-TERRA C18 column using a mobile phase composed of 20 mM KH(2)PO(4), acetonitrile, and n-octylamine (76:24:0.05, v/v/v) at 40 degrees C and detected at 237 nm. The described assay was validated in terms of linearity, accuracy, precision, recovery and lower limit of quantification according to the FDA validation guidelines. Calibration curves were linear with a coefficient of variation (r) greater than 0.998. Accuracy ranged from 92.3% to 106.0% and precision was between 2.3% and 8.2%. The method has been applied to plasma and cerebrospinal fluid samples obtained from patients treated with oxcarbazepine, both in monotherapy and adjunctive therapy.
Medas, Daniela; De Giudici, Giovanni; Casu, Maria Antonietta; Musu, Elodia; Gianoncelli, Alessandra; Iadecola, Antonella; Meneghini, Carlo; Tamburini, Elena; Sprocati, Anna Rosa; Turnau, Katarzyna; Lattanzi, Pierfranco
2015-02-03
Euphorbia pithyusa L. was used in a plant growth-promoting assisted field trial experiment. To unravel the microscopic processes at the interface, thin slices of E. pithyusa roots were investigated by micro-X-ray fluorescence mapping. Roots and rhizosphere materials were examined by X-ray absorption spectroscopy at the Zn K-edge, X-ray diffraction, and scanning electron microscopy. Results indicate some features common to all the investigated samples. (i) In the rhizosphere of E. pithyusa, Zn was found to exist in different phases. (ii) Si and Al are mainly concentrated in a rim at the epidermis of the roots. (iii) Zn is mostly stored in root epidermis and does not appear to be coordinated to organic molecules but mainly occurs in mineral phases such as Zn silicates. We interpreted that roots of E. pithyusa significantly promote mineral evolution in the rhizosphere. Concomitantly, the plant uses Si and Al extracted by soil minerals to build a biomineralization rim, which can capture Zn. This Zn silicate biomineralization has relevant implications for phytoremediation techniques and for further biotechnology development, which can be better designed and developed after specific knowledge of molecular processes ruling mineral evolution and biomineralization processes has been gained.
Investigational opioid antagonists for treating opioid-induced bowel dysfunction.
Mozaffari, Shilan; Nikfar, Shekoufeh; Abdollahi, Mohammad
2018-03-01
Opioids have been highlighted for their role in pain relief among cancer and non-cancer patients. Novel agents have been investigated to reduce opioid-induced constipation (OIC) as the main adverse effect that may lead to treatment discontinuation. Development of peripherally acting mu-opioid receptor antagonists (PAMORA) has resulted in a novel approach to preserve the efficacy of pain control along with less OIC. Areas covered: Clinical evidence for investigational PAMORAs was reviewed and clinical trials on investigational agents to reduce OIC were included. TD-1211 is currently being evaluated in Phase II clinical trial. Oxycodone-naltrexone and ADL-5945 went through Phase III clinical trials, but have been discontinued. Expert opinion: There is a substantial need to develop agents with specific pharmacokinetic properties to meet the needs of patients with underlying diseases. Holding the efficacy of a medicine with the highest selectivity on targeted receptors and the least adverse effects is the main approach in upcoming investigations to improve patients' quality of life (QoL). Novel agents to reduce opioid-induced bowel dysfunction (OIBD) that do not reverse peripherally mediated pain analgesia are of great interest. Direct comparison of available agents in this field is lacking in the literature.
NASA Astrophysics Data System (ADS)
Madrigal, R. F.; Blaya, L. Carretero S.; Ulibarrena, M.; Beléndez, A.; Fimia, A.
2002-01-01
In this paper we present the theoretical and experimental study of diffraction efficiency of unbleached holograms, showing that the volume fraction of metallic silver inside the gelatin after development ( q) is the main parameter in the behavior of the holographic grating properties. Using this fact, and the obtained relationship between pH and q, we have found values of diffraction efficiencies near 30% with a developing time of 3 min without bleaching step.
Effect of liquid droplets on turbulence in a round gaseous jet
NASA Technical Reports Server (NTRS)
Mostafa, A. A.; Elghobashi, S. E.
1986-01-01
The main objective of this investigation is to develop a two-equation turbulence model for dilute vaporizing sprays or in general for dispersed two-phase flows including the effects of phase changes. The model that accounts for the interaction between the two phases is based on rigorously derived equations for turbulence kinetic energy (K) and its dissipation rate epsilon of the carrier phase using the momentum equation of that phase. Closure is achieved by modeling the turbulent correlations, up to third order, in the equations of the mean motion, concentration of the vapor in the carrier phase, and the kinetic energy of turbulence and its dissipation rate for the carrier phase. The governing equations are presented in both the exact and the modeled formes. The governing equations are solved numerically using a finite-difference procedure to test the presented model for the flow of a turbulent axisymmetric gaseous jet laden with either evaporating liquid droplets or solid particles. The predictions include the distribution of the mean velocity, volume fractions of the different phases, concentration of the evaporated material in the carrier phase, turbulence intensity and shear stress of the carrier phase, droplet diameter distribution, and the jet spreading rate. The predictions are in good agreement with the experimental data.
Method of synthesized phase objects for pattern recognition with rotation invariance
NASA Astrophysics Data System (ADS)
Ostroukh, Alexander P.; Butok, Alexander M.; Shvets, Rostislav A.; Yezhov, Pavel V.; Kim, Jin-Tae; Kuzmenko, Alexander V.
2015-11-01
We present a development of the method of synthesized phase objects (SPO-method) [1] for the rotation-invariant pattern recognition. For the standard method of recognition and the SPO-method, the comparison of the parameters of correlation signals for a number of amplitude objects is executed at the realization of a rotation in an optical-digital correlator with the joint Fourier transformation. It is shown that not only the invariance relative to a rotation at a realization of the joint correlation for synthesized phase objects (SP-objects) but also the main advantage of the method of SP-objects over the reference one such as the unified δ-like recognition signal with the largest possible signal-to-noise ratio independent of the type of an object are attained.
Chin, Sanghoon; Thévenaz, Luc; Sancho, Juan; Sales, Salvador; Capmany, José; Berger, Perrine; Bourderionnet, Jérôme; Dolfi, Daniel
2010-10-11
We experimentally demonstrate a novel technique to process broadband microwave signals, using all-optically tunable true time delay in optical fibers. The configuration to achieve true time delay basically consists of two main stages: photonic RF phase shifter and slow light, based on stimulated Brillouin scattering in fibers. Dispersion properties of fibers are controlled, separately at optical carrier frequency and in the vicinity of microwave signal bandwidth. This way time delay induced within the signal bandwidth can be manipulated to correctly act as true time delay with a proper phase compensation introduced to the optical carrier. We completely analyzed the generated true time delay as a promising solution to feed phased array antenna for radar systems and to develop dynamically reconfigurable microwave photonic filters.
Towards Citizen Co-Created Public Service Apps †
Emaldi, Mikel; Aguilera, Unai; López-de-Ipiña, Diego; Pérez-Velasco, Jorge
2017-01-01
WeLive project’s main objective is about transforming the current e-government approach by providing a new paradigm based on a new open model oriented towards the design, production and deployment of public services and mobile apps based on the collaboration of different stakeholders. These stakeholders form the quadruple helix, i.e., citizens, private companies, research institutes and public administrations. Through the application of open innovation, open data and open services paradigms, the framework developed within the WeLive project enables the co-creation of urban apps. In this paper, we extend the description of the WeLive platform presented at , plus the preliminary results of the first pilot phase. The two-phase evaluation methodology designed and the evaluation results of first pilot sub-phase are also presented. PMID:28574460
Shuttle-tethered satellite system definition study extension
NASA Technical Reports Server (NTRS)
1980-01-01
A system requirements definition and configuration study (Phase B) of the Tethered Satellite System (TSS) was conducted during the period 14 November 1977 to 27 February 1979. Subsequently a study extension was conducted during the period 13 June 1979 to 30 June 1980, for the purpose of refining the requirements identified during the main phase of the study, and studying in some detail the implications of accommodating various types of scientific experiments on the initial verification flight mission. An executive overview is given of the Tethered Satellite System definition developed during the study. The results of specific study tasks undertaken in the extension phase of the study are reported. Feasibility of the Tethered Satellite System has been established with reasonable confidence and the groundwork laid for proceeding with hardware design for the verification mission.
NASA Astrophysics Data System (ADS)
Baishev, D. G.; Moiseyev, A. V.; Boroyev, R. N.; Kobyakova, S. E.; Stepanov, A. E.; Mandrikova, O. V.; Solovev, I. S.; Khomutov, S. Yu.; Polozov, Yu. A.; Yoshikawa, A.; Yumoto, K.
2015-12-01
Magnetic and ionospheric disturbances in the far eastern region of Russia during the magnetic storm of 5 April 2010 are studied using data of geophysical stations operated by IKFIA SB RAS and IKIR FEB RAS. By performing wavelet analysis of experimental data, the wavelet powers of geomagnetic perturbations at different stations are estimated, in an attempt to investigate the dynamical development of a geomagnetic storm. It is shown that, though weak geomagnetic disturbances were present prior to the main phase of magnetic storm, the variations of the magnetic field during a storm development were found to be rather strong. The highest intensity of geomagnetic disturbances during the interplanetary shock at the Earth's magnetosphere was observed at KTN (L~9) while at ZYK (L~4) strongest geomagnetic perturbations occurred during the magnetospheric substorm with the onset at 09:03 UT. Large geomagnetic fluctuations were recorded at TIX and CHD (L~5-6), when the High-Intensity Long-Duration Continuous AE Activity (HILDCAA) was observed on 6 April 2010. Ionospheric conditions at YAK (L~3.4) and PET (L~2.2) were characterized by a pre-storm enhancement in the electron density in the F2 layer on 4 April 2010 and prolonged negative phase of the ionospheric storm during the main and recovery phases of magnetic storm on 6-8 April 2010. These experimental results underscore the importance of multi-instrumental observations and provide clues to the complex interactive processes.
May, Michael; Paul, Elizabeth; Katovic, Vladimir
2015-11-01
A vacuum sublimation module of axisymmetric geometry was developed and employed to purify solid-phase materials. The module provides certain practical advantages and it comprises: a metering valve, glass collector, glass lower body, main seal, threaded bushing, and glass internal cartridge (the latter to contain starting material). A complementary process was developed to de-solvate, sublime, weigh, and collect solid chemical materials exemplified by oxalic acid, ferrocene, pentachlorobenzene, chrysene, and urea. The oxalic acid sublimate was analyzed by titration, melting range, Fourier Transform Infrared (FT-IR) Spectroscopy, cyclic voltammetry, and its (aqueous phase) electrolytically generated gas. The analytical data were consistent with a high-purity, anhydrous oxalic acid sublimate. Cyclic voltammograms of 0.11 mol. % oxalic acid in water displayed a 2.1 V window on glassy carbon electrode beyond which electrolytic decomposition occurs. During module testing, fifteen relatively pure materials were sublimed with (energy efficient) passive cooling and the solid-phase recovery averaged 95 mass %. Key module design features include: compact vertical geometry, low-angle conical collector, uniformly compressed main seal, modest power consumption, transparency, glovebox compatibility, cooling options, and preferential conductive heat transfer. To help evaluate the structural (module) heat transfer, vertical temperature profiles along the dynamically evacuated lower body were measured versus electric heater power: for example, an input of 18.6 W generated a temperature 443-K at the bottom. Experimental results and engineering calculations indicate that during sublimation, solid conduction is the primary mode of heat transfer to the starting material.
Jiménez-Díaz, I; Vela-Soria, F; Rodríguez-Gómez, R; Zafra-Gómez, A; Ballesteros, O; Navalón, A
2015-09-10
In the present work, a review of the analytical methods developed in the last 15 years for the determination of endocrine disrupting chemicals (EDCs) in human samples related with children, including placenta, cord blood, amniotic fluid, maternal blood, maternal urine and breast milk, is proposed. Children are highly vulnerable to toxic chemicals in the environment. Among these environmental contaminants to which children are at risk of exposure are EDCs -substances able to alter the normal hormone function of wildlife and humans-. The work focuses mainly on sample preparation and instrumental techniques used for the detection and quantification of the analytes. The sample preparation techniques include, not only liquid-liquid extraction (LLE) and solid-phase extraction (SPE), but also modern microextraction techniques such as extraction with molecular imprinted polymers (MIPs), stir-bar sorptive extraction (SBSE), hollow-fiber liquid-phase microextraction (HF-LPME), dispersive liquid-liquid microextraction (DLLME), matrix solid phase dispersion (MSPD) or ultrasound-assisted extraction (UAE), which are becoming alternatives in the analysis of human samples. Most studies focus on minimizing the number of steps and using the lowest solvent amounts in the sample treatment. The usual instrumental techniques employed include liquid chromatography (LC), gas chromatography (GC) mainly coupled to tandem mass spectrometry. Multiresidue methods are being developed for the determination of several families of EDCs with one extraction step and limited sample preparation. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Quiers, M.; Perrette, Y.; Etienne, D.; Develle, A. L.; Jacq, K.
2017-12-01
The use of organic proxies increases in paleoenvironmental reconstructions from natural archives. Major advances have been achieved by the development of new highly informative molecular proxies usually linked to specific compounds. While studies focused on targeted compounds, offering a high information degree, advances on bulk organic matter are limited. However, this bulk is the main contributor to carbon cycle and has been shown to be a driver of many mineral or organic compounds transfer and record. Development of target proxies need complementary information on bulk organic matter to understand biases link to controlling factors or analytical methods, and provide a robust interpretation. Fluorescence methods have often been employed to characterize and quantify organic matter. However, these technics are mainly developed for liquid samples, inducing material and resolution loss when working on natural archives (either stalagmite or sediments). High-resolution solid phase fluorescence (SPF) was developed on speleothems. This method allows now to analyse organic matter quality and quantity if procedure to constrain the optical density are adopted. In fact, a calibration method using liquid phase fluorescence (LPF) was developed for speleothem, allowing to quantify organic carbon at high-resolution. We report here an application of such a procedure SPF/LPF measurements on lake sediments. In order to avoid sediment matrix effects on the fluorescence signal, a calibration using LPF measurements was realised. First results using this method provided organic matter quality record of different organic matter compounds (humic-like, protein-like and chlorophylle-like compounds) at high resolution for the sediment core. High resolution organic matter fluxes are obtained in a second time, applying pragmatic chemometrics model (non linear models, partial least square models) on high resolution fluorescence data. SPF method can be considered as a promising tool for high resolution record on organic matter quality and quantity. Potential application of this method will be evocated (lake ecosystem dynamic, changes in trophic levels)
Collaborative development of the EPICS Qt framework Phase I Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mayssat, Robert E.
At Lyncean, a private company spun-off from technology developed at the SLAC National Lab, we have been using EPICS for over a decade. EPICS is ubiquitous on our flagship product – the Compact Light Source. EPICS is not only used to control our laser and accelerator systems, but also to control our x-ray beamlines. The goal of this SBIR is for Lyncean Technologies to spearhead a worldwide collaborative effort for the development of control system tools for EPICS using the Qt framework, a C++-based coding environment that could serve as a competitive alternative to the Java-based Control System Studio (CSS).more » This grant's Phase I, not unlike a feasibility study, is designed for planning and scoping the preparatory work needed for Phase II or other funding opportunities. The three main objectives of this Phase I are (1) to become better acquainted with the existing EPICS Qt software and Qt framework in order to evaluate the best options for ongoing development, (2) to demonstrate that our engineers can lead the EPICS community and jump-start the Qt collaboration, and (3) to identify a scope for our future work with solicited feedback from the EPICS community. This Phase I report includes key technical findings. It clarifies the differences between the two apparently-competing EPICS Qt implementations, caQtDM and the QE Framework; it explains how to create python-bindings, and compares Qt graphical libraries. But this report is also a personal story that narrates the birth of a collaboration. Starting a collaboration is not the work of a single individual, but the work of many. Therefore this report is also an attempt to publicly give credit to many who supported the effort. The main take-away from this grant is the successful birth of an EPICS Qt collaboration, seeded with existing software from the PSI and the Australian Synchrotron. But a lot more needs to be done for the collaboration founders' vision to be realized, and for the collaboration to reach its full potential. To help define the scope of future work, a useful approach we have identified is user experience design (UXD) and is discussed herein.« less
NASA Astrophysics Data System (ADS)
Sorathia, K.; Ukhorskiy, A. Y.; Merkin, V. G.; Wiltberger, M. J.; Lyon, J.; Claudepierre, S. G.; Fennell, J. F.
2017-12-01
During geomagnetic storms the intensities of radiation belt electrons exhibit dramatic variability. In the main phase electron intensities exhibit deep depletion over a broad region of the outer belt. The intensities then increase during the recovery phase, often to levels that significantly exceed their pre-storm values. In this study we analyze the depletion, recovery and enhancement of radiation belt intensities during the 2013 St. Patrick's geomagnetic storm. We simulate the dynamics of high-energy electrons using our newly-developed test-particle radiation belt model (CHIMP) based on a hybrid guiding-center/Lorentz integrator and electromagnetic fields derived from high-resolution global MHD (LFM) simulations. Our approach differs from previous work in that we use MHD flow information to identify and seed test-particles into regions of strong convection in the magnetotail. We address two science questions: 1) what are the relative roles of magnetopause losses, transport-driven atmospheric precipitation, and adiabatic cooling in the radiation belt depletion during the storm main phase? and 2) to what extent can enhanced convection/mesoscale injections account for the radiation belt buildup during the recovery phase? Our analysis is based on long-term model simulation and the comparison of our model results with electron intensity measurements from the MAGEIS experiment of the Van Allen Probes mission.
NASA Technical Reports Server (NTRS)
Fayssal, Safie; Weldon, Danny
2008-01-01
The United States National Aeronautics and Space Administration (NASA) is in the midst of a space exploration program called Constellation to send crew and cargo to the international Space Station, to the moon, and beyond. As part of the Constellation program, a new launch vehicle, Ares I, is being developed by NASA Marshall Space Flight Center. Designing a launch vehicle with high reliability and increased safety requires a significant effort in understanding design variability and design uncertainty at the various levels of the design (system, element, subsystem, component, etc.) and throughout the various design phases (conceptual, preliminary design, etc.). In a previous paper [1] we discussed a probabilistic functional failure analysis approach intended mainly to support system requirements definition, system design, and element design during the early design phases. This paper provides an overview of the application of probabilistic engineering methods to support the detailed subsystem/component design and development as part of the "Design for Reliability and Safety" approach for the new Ares I Launch Vehicle. Specifically, the paper discusses probabilistic engineering design analysis cases that had major impact on the design and manufacturing of the Space Shuttle hardware. The cases represent important lessons learned from the Space Shuttle Program and clearly demonstrate the significance of probabilistic engineering analysis in better understanding design deficiencies and identifying potential design improvement for Ares I. The paper also discusses the probabilistic functional failure analysis approach applied during the early design phases of Ares I and the forward plans for probabilistic design analysis in the detailed design and development phases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, William; Krakowiak, Konrad J.; Ulm, Franz-Josef, E-mail: ulm@mit.edu
2014-01-15
According to recent developments in cement clinker engineering, the optimization of chemical substitutions in the main clinker phases offers a promising approach to improve both reactivity and grindability of clinkers. Thus, monitoring the chemistry of the phases may become part of the quality control at the cement plants, along with the usual measurements of the abundance of the mineralogical phases (quantitative X-ray diffraction) and the bulk chemistry (X-ray fluorescence). This paper presents a new method to assess these three complementary quantities with a single experiment. The method is based on electron microprobe spot analyses, performed over a grid located onmore » a representative surface of the sample and interpreted with advanced statistical tools. This paper describes the method and the experimental program performed on industrial clinkers to establish the accuracy in comparison to conventional methods. -- Highlights: •A new method of clinker characterization •Combination of electron probe technique with cluster analysis •Simultaneous assessment of phase abundance, composition and bulk chemistry •Experimental validation performed on industrial clinkers.« less
Development of phase detection schemes based on surface plasmon resonance using interferometry.
Kashif, Muhammad; Bakar, Ahmad Ashrif A; Arsad, Norhana; Shaari, Sahbudin
2014-08-28
Surface plasmon resonance (SPR) is a novel optical sensing technique with a unique ability to monitor molecular binding in real-time for biological and chemical sensor applications. Interferometry is an excellent tool for accurate measurement of SPR changes, the measurement and comparison is made for the sensitivity, dynamic range and resolution of the different analytes using interferometry techniques. SPR interferometry can also employ phase detection in addition to the amplitude of the reflected light wave, and the phase changes more rapidly compared with other approaches, i.e., intensity, angle and wavelength. Therefore, the SPR phase interferometer offers the advantages of spatial phase resolution and high sensitivity. This work discusses the advancements in interferometric SPR methods to measure the phase shifts due to refractive index changes. The main application areas of SPR sensors are demonstrated, i.e., the Fabry-Perot interferometer, Michelson interferometer and Mach-Zehnder interferometer, with different configurations. The three interferometers are discussed in detail, and solutions are suggested to enhance the performance parameters that will aid in future biological and chemical sensors.
Development of Phase Detection Schemes Based on Surface Plasmon Resonance Using Interferometry
Kashif, Muhammad; Bakar, Ahmad Ashrif A.; Arsad, Norhana; Shaari, Sahbudin
2014-01-01
Surface plasmon resonance (SPR) is a novel optical sensing technique with a unique ability to monitor molecular binding in real-time for biological and chemical sensor applications. Interferometry is an excellent tool for accurate measurement of SPR changes, the measurement and comparison is made for the sensitivity, dynamic range and resolution of the different analytes using interferometry techniques. SPR interferometry can also employ phase detection in addition to the amplitude of the reflected light wave, and the phase changes more rapidly compared with other approaches, i.e., intensity, angle and wavelength. Therefore, the SPR phase interferometer offers the advantages of spatial phase resolution and high sensitivity. This work discusses the advancements in interferometric SPR methods to measure the phase shifts due to refractive index changes. The main application areas of SPR sensors are demonstrated, i.e., the Fabry-Perot interferometer, Michelson interferometer and Mach-Zehnder interferometer, with different configurations. The three interferometers are discussed in detail, and solutions are suggested to enhance the performance parameters that will aid in future biological and chemical sensors. PMID:25171117
Influence of relative permeabilities on chemical enhanced oil recovery
NASA Astrophysics Data System (ADS)
Destefanis, M. F.; Savioli, G. B.
2011-05-01
The main objective of chemical flooding is to mobilize the trapped oil remaining after a secondary recovery by waterflooding. This purpose is achieved by lowering the oil-water interfacial tension and producing partial miscibility between both phases. The chemical partition among phases (phase behavior) influences all other physical properties. In particular, it affects residual saturations determining relative permeability curves. Relative permeabilities rule the flow of each phase through the porous medium, so they play an essential role in oil recovery. Therefore, in this work we study the influence of relative permeabilities on the behavior of a surfactant-polymer flooding for the three different types of phase behavior. This analysis is performed applying the 3D compositional numerical simulator UTCHEM developed at the University of Texas at Austin. From the examples studied, we conclude that the influence of relative permeabilities depends on the type of phase behavior, i.e., as microemulsion relative permeability decreases, oil recovery increases for Types II(+) and III while slightly decreases for Type II(-). Moreover, a better displacement efficiency is observed for Types II(+) and III, because they behave similarly to a miscible displacement.
Alteration minerals in impact-generated hydrothermal systems - Exploring host rock variability
NASA Astrophysics Data System (ADS)
Schwenzer, Susanne P.; Kring, David A.
2013-09-01
Impact-generated hydrothermal systems have been previously linked to the alteration of Mars’ crust and the production of secondary mineral assemblages seen from orbit. The sensitivity of the resultant assemblages has not yet been evaluated as a function of precursor primary rock compositions. In this work, we use thermochemical modeling to explore the variety of minerals that could be produced by altering several known lithologies based on martian meteorite compositions. For a basaltic host rock lithology (Dhofar 378, Humphrey) the main alteration phases are feldspar, zeolite, pyroxene, chlorite, clay (nontronite, kaolinite), and hematite; for a lherzolithic host rock lithology (LEW 88516) the main alteration phases are amphibole, serpentine, chlorite, clay (nontronite, kaolinite), and hematite; and for an ultramafic host rock lithology (Chassigny) the main minerals are secondary olivine, serpentine, magnetite, quartz, and hematite. These assemblages and proportions of phases in each of those cases depend on W/R and temperature. Integrating geologic, hydrologic and alteration mineral evidence, we have developed a model to illustrate the distribution of alteration assemblages that occur in different levels of an impact structure. At the surface, hot, hydrous alteration affects the ejecta and melt sheet producing clay and chlorite. Deeper in the subsurface and depending on the permeability of the rock, a variety of minerals - smectite, chlorite, serpentine, amphiboles and hematite - are produced in a circulating hydrothermal system. These modeled mineral distributions should assist with interpretation of orbital observations and help guide surface exploration by rovers and sample return assets.
Zhang, Yan; Jiao, Shengyin; Lv, Jia; Du, Renjia; Yan, Xiaoni; Wan, Caixia; Zhang, Ruijuan; Han, Bei
2017-01-01
Clostridium beijerinckii DG-8052, derived from NCIMB 8052, cannot produce solvent or form spores, a phenomenon known as degeneration. To explore the mechanisms of degeneration at the gene level, transcriptomic profiles of the wild-type 8052 and DG-8052 strains were compared. Expression of 5168 genes comprising 98.6% of the genome was assessed. Interestingly, 548 and 702 genes were significantly up-regulated in the acidogenesis and solventogenesis phases of DG-8052, respectively, and mainly responsible for the phosphotransferase system, sugar metabolic pathways, and chemotaxis; meanwhile, 699 and 797 genes were significantly down-regulated, respectively, and mainly responsible for sporulation, oxidoreduction, and solventogenesis. The functions of some altered genes, including 286 and 333 at the acidogenesis and solventogenesis phases, respectively, remain unknown. Dysregulation of the fermentation machinery was accompanied by lower transcription levels of glycolysis rate-limiting enzymes (pfk and pyk), and higher transcription of cell chemotaxis genes (cheA, cheB, cheR, cheW, and cheY), controlled mainly by σ54 at acidogenesis. Meanwhile, abnormal spore formation was associated with repressed spo0A, sigE, sigF, sigG, and sigK which are positively regulated by σ70, and correspondingly inhibited expression of CoA-transferase at the solventogenesis phase. These findings indicated that morphological and physiological changes in the degenerated Clostridium strain may be related to altered expression of sigma factors, providing valuable targets for strain development of Clostridium species. PMID:28194137
Kumar, Ashwini; Gaurav; Malik, Ashok Kumar; Tewary, Dhananjay Kumar; Singh, Baldev
2008-03-03
Solid phase microextraction (SPME) is an innovative, solvent free technology that is fast, economical and versatile. SPME is a fiber coated with a liquid (polymer), a solid (sorbent) or a combination of both. The fiber coating takes up the compounds from the sample by absorption in the case of liquid coatings or adsorption in the case of solid coatings. The SPME fiber is then transferred with the help of a syringe like device into the analytical instrument for desorption and analysis of the target analytes. The sol-gel process provides a versatile method to prepare size, shape and charge selective materials of high purity and homogeneity by means of preparation techniques different from the traditional ones, for the chemical analysis. This review is on the current state of the art and future trends in the developments of solid phase microextraction (SPME) fibers using sol-gel method. To achieve more selective determination of different compound classes, the variety of different coating material for SPME fibers has increased. Further developments in SPME as a highly efficient extraction technique, will greatly depend on new breakthroughs in the area of new coating material developments for the SPME fibers. In sol-gel approach, appropriate sol-gel precursors and other building blocks can be selected to create a stationary phase with desired structural and surface properties. This approach is efficient in integrating the advantageous properties of organic and inorganic material systems and thereby increasing and improving the extraction selectivity of the produced amalgam organic-inorganic stationary phases. This review is mainly focused on recent advanced developments in the design, synthesis, characterisation, properties and application of sol-gel in preparation of coatings for the SPME fibers.
Upstream Optioneering: Optimising Higher Activity Waste Management
DOE Office of Scientific and Technical Information (OSTI.GOV)
McTeer, Jennifer; Morris, Jenny; Wickham, Stephen
2013-07-01
The Upstream Optioneering project was created by the Nuclear Decommissioning Authority (NDA) Radioactive Waste Management Directorate (RWMD) to support the development and implementation of opportunities to optimise the management of UK higher activity waste, spent fuel and other materials that may be disposed of in a geological disposal facility. The project works in an integrative manner with the NDA, RWMD and waste producers, and was split into three phases: - In Phase 1 waste management opportunities were identified and collated from across the NDA estate. - In Phase 2, opportunities collated during Phase 1, were further consolidated, analysed and prioritisedmore » to develop a three year work programme. Prioritisation ensured that resources were deployed appropriately and opportunities can be realised before the potential benefit diminishes. - Phase 3, which began in April 2012, comprises a three year work programme to address the prioritised opportunities. Work varies from direct implementation of opportunities to scoping studies that may pave the way for more detailed subsequent work by Site Licence Companies. The work programme is flexible and, subject to change control, varies depending on the needs of project sponsors (RWMD, NDA Strategy and NDA Delivery). This paper provides an overview of the Upstream Optioneering project (focusing particularly on Phases 2 and 3), summarises work carried out to date within the three year work programme, and provides some examples of the main findings concerning specific opportunities from Year One of the Phase 3 work programme. (authors)« less
Achievement of high coercivity in sintered R-Fe-B magnets based on misch-metal by dual alloy method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Niu, E, E-mail: niue@aphy.iphy.ac.cn; Wang, Zhen-Xi; Beijing Zhong Ke San Huan Research, No.10 Chuangxin Road, Changping District, Beijing 102200
2014-03-21
The R-Fe-B (R, rare earth) sintered magnets prepared with different ratio of alloys of MM-Fe-B (MM, misch-metal) and Nd-Fe-B by dual alloy method were investigated. As expected, the high ratio of MM-Fe-B alloy degrades the hard magnetic properties heavily with intrinsic coercivity lower than 5 kOe. When the atomic ratio MM/R ≤ 21.5% the magnetic properties can reach a practical level of B{sub r} ≥ 12.1 kGs, H{sub cj} ≥ 10.7 kOe, and (BH){sub max} ≥ 34.0 MGOe. And the effect of H{sub cj} enhancement by the grain boundary diffusion process is obvious when MM/R ≤ 21.5%. It is revealed that the decrement of intrinsic magnetic properties of R{sub 2}Fe{submore » 14}B matrix phase is not the main reason of the degradation of the magnets with high MM ratio. The change of deteriorated microstructure together with phase component plays fundamental roles in low H{sub cj}. In high MM ratio magnets, (a) after annealing, Ce atoms inside main phase are inclined to be segregated in the outer layer of the main phase grains; (b) there is no thin layer of Ce-rich phase as an analogue of Nd-rich phase to separate main phase grains; (c) excessive Ce tends to form CeFe{sub 2} grains.« less
NASA Technical Reports Server (NTRS)
Patel, V. L.
1975-01-01
Twenty-one geomagnetic storm events during 1966 and 1970 were studied by using simultaneous interplanetary magnetic field and plasma parameters. Explorer 33 and 35 field and plasma data were analyzed on large-scale (hourly) and small-scale (3 min.) during the time interval coincident with initial phase of the geomagnetic storms. The solar-ecliptic Bz component turns southward at the end of the initial phase, thus triggering the main phase decrease in Dst geomagnetic field. When the Bz is already negative, its value becomes further negative. The By component also shows large fluctuations along with Bz. When there are no clear changes in the Bz component, the By shows abrupt changes at the main phase onet. On the small-scale behavior of the magnetic field and electric field (E=-VxB) studied in details for the three events, it is found that the field fluctuations in By, Bz and Ey and Ez are present in the initial phase. These fluctuations become larger just before the main phase of the storm begins. In the largescale behavior field remains quiet because the small scale variations are averaged out.
Affonso, A G; Queiroz, H L; Novo, E M L M
2015-11-01
This paper examines water properties from lakes, (depression lakes, sensu Junk et al., 2012), channels (scroll lakes with high connectivity, sensu Junk et al., 2012) and paleo-channels (scroll lakes with low connectivity-sensu Junk et al., 2012, locally called ressacas) located in Mamirauá Sustainable Development Reserve, in Central Amazon floodplain, Amazonas, Brazil. We analysed surface temperature, conductivity, pH, dissolved oxygen, turbidity, transparency, suspended inorganic and organic matter, chlorophyll-a, pheophytin, total nitrogen, total phosphorus, organic and inorganic carbon in 2009 high water phase, 2009 and 2010 low water phases. Multivariate statistical analyses of 24 aquatic systems (6 ressacas, 12 lakes and 6 channels, 142 samples) were applied to the variables in order to: 1) quantify differences among aquatic system types; 2) assess how those differences are affected in the different phases of the hydrological year. First, we analysed the entire set of variables to test for differences among phases of the hydrological year and types of aquatic systems using a PERMANOVA two-way crossed design. The results showed that the all measured limnological variables are distinct regarding both factors: types of aquatic systems and hydrological phases. In general, the magnitude and amplitude of all variables were higher in the low water phase than in the high water phase, except for water transparency in all aquatic system's types. PERMANOVA showed that the differences between aquatic system's types and hydrological phases of all variables were highly significant for both main factors (type and phase) and for the type x phase interaction. Limnological patterns of Amazon floodplain aquatic systems are highly dynamic, dependent on the surrounding environment, flood pulse, main river input and system type. These patterns show how undisturbed systems respond to natural variability in such a diverse environment, and how distinct are those aquatic systems, especially during the low water phase. Aquatic systems in Mamirauá floodplain represent limnological patterns of almost undisturbed areas and can be used as future reference for comparison with disturbed areas, such as those of the Lower Amazon, and as a baseline for studies on the effects of anthropogenic influences and climate change and on Amazon aquatic ecosystem.
Heat transfer in rocket engine combustion chambers and regeneratively cooled nozzles
NASA Technical Reports Server (NTRS)
1993-01-01
A conjugate heat transfer computational fluid dynamics (CFD) model to describe regenerative cooling in the main combustion chamber and nozzle and in the injector faceplate region for a launch vehicle class liquid rocket engine was developed. An injector model for sprays which treats the fluid as a variable density, single-phase media was formulated, incorporated into a version of the FDNS code, and used to simulate the injector flow typical of that in the Space Shuttle Main Engine (SSME). Various chamber related heat transfer analyses were made to verify the predictive capability of the conjugate heat transfer analysis provided by the FDNS code. The density based version of the FDNS code with the real fluid property models developed was successful in predicting the streamtube combustion of individual injector elements.
Phase 1 Development Testing of the Advanced Manufacturing Demonstrator Engine
NASA Technical Reports Server (NTRS)
Case, Nicholas L.; Eddleman, David E.; Calvert, Marty R.; Bullard, David B.; Martin, Michael A.; Wall, Thomas R.
2016-01-01
The Additive Manufacturing Development Breadboard Engine (BBE) is a pressure-fed liquid oxygen/pump-fed liquid hydrogen (LOX/LH2) expander cycle engine that was built and operated by NASA at Marshall Space Flight Center's East Test Area. The breadboard engine was conceived as a technology demonstrator for the additive manufacturing technologies for an advanced upper stage prototype engine. The components tested on the breadboard engine included an ablative chamber, injector, main fuel valve, turbine bypass valve, a main oxidizer valve, a mixer and the fuel turbopump. All parts minus the ablative chamber were additively manufactured. The BBE was successfully hot fire tested seven times. Data collected from the test series will be used for follow on demonstration tests with a liquid oxygen turbopump and a regeneratively cooled chamber and nozzle.
Participation of the Olfactory Bulb in Circadian Organization during Early Postnatal Life in Rabbits
Navarrete, Erika; Ortega-Bernal, Juan Roberto; Trejo-Muñoz, Lucero; Díaz, Georgina; Montúfar-Chaveznava, Rodrigo; Caldelas, Ivette
2016-01-01
Experimental evidence indicates that during pre-visual stages of development in mammals, circadian regulation is still not under the control of the light-entrainable hypothalamic pacemaker, raising the possibility that the circadian rhythmicity that occurs during postnatal development is under the control of peripheral oscillators, such as the main olfactory bulb (MOB). We evaluated the outcome of olfactory bulbectomy on the temporal pattern of core body temperature and gross locomotor activity in newborn rabbits. From postnatal day 1 (P1), pups were randomly assigned to one of the following conditions: intact pups (INT), intact pups fed by enteral gavage (INT+ENT), sham operated pups (SHAM), pups with unilateral lesions of the olfactory bulb (OBx-UNI), and pups with bilateral lesions of the olfactory bulb (OBx-BI). At the beginning of the experiment, from P1-8, the animals in all groups were fed at 11:00, from P9-13 the feeding schedule was delayed 6 h (17:00), and finally, from P14-15 the animals were subjected to fasting conditions. The rabbit pups of the INT, INT+ENT, SHAM and OBx-UNI groups exhibited a clear circadian rhythmicity in body temperature and locomotor activity, with a conspicuous anticipatory rise hours prior to the nursing or feeding schedule, which persisted even during fasting conditions. In addition, phase delays in the nursing or feeding schedule induced a clear phase shift in both parameters. In contrast, the OBx-BI group exhibited atypical rhythmicity in both parameters under entrained conditions that altered the anticipatory component, as well as deficient phase control of both rhythms. The present results demonstrate that the expression of circadian rhythmicity at behavioral and physiological levels during early stages of rabbit development largely depends on the integrity of the main olfactory bulb. PMID:27305041
NASA Astrophysics Data System (ADS)
Adatte, Thierry; Sordet, Valentin; Keller, Gerta; Schoene, Blair; Samperton, Kyle; Khadri, Syed
2016-04-01
Deccan Traps erupted in three main phases with 6% total Deccan volume in phase-1 (C30n), 80% in phase-2 (C29r) and 14% in phase-3 (C29n). Recent studies indicate that the bulk (80%) of Deccan trap eruptions (phase-2) occurred over a relatively short time interval in magnetic polarity C29r. U-Pb zircon geochronology shows that the main phase-2 began 250 ky before the Cretaceous-Tertiary (KT) mass extinction and continued into the early Danian suggesting a cause-and-effect relationship. In India a strong floral response is observed as a direct consequence of volcanic phase-2. Shortly after the onset of Deccan phase-2, the floral association dominated by gymnosperms and angiosperms was decimated as indicated by a sharp decrease in pollen and spores coupled with the appearance of fungi, which mark increasing stress conditions as a direct result of volcanic activity. The inter-trappean sediments deposited in phase-2 are characterized by the highest alteration CIA index values suggesting increased acid rains due to SO2 emissions. In addition, a sharp decrease in pollen and spores coupled with the appearance of fungi mark increasing stress conditions, which are likely a direct result of volcanic activity. Bulk organic geochemistry points to a strong degradation of the indigenous organic matter, suggesting that the biomass was oxidized in acidic conditions triggered by intense volcanic activity. Closer to the eruption center, the lava flows are generally separated by red weathered horizons known as red boles that mark quiescent periods between basalt flows. Red boles have increasingly attracted the attention of researchers to understand the climatic and paleoenvironmental impact of Continental Flood Basalts (CFB). Recent advances in U-Pb dating of Deccan lava flows, studies of weathering patterns and paleoclimatic information gained from multiproxy analyses of red bole beds (e.g., lithology, mineralogy, geochemistry) yield crucial evidence of environmental changes triggered by volcanic activity. Red boles consist mainly of red silty clays characterized by concentrations of immobile elements such as Al and Fe3+ ions that are typical of paleo-laterites which probably developed during the short periods of weathering between eruptions. At least 30 thick red bole layers are present in C29r below the KT boundary between lava flows of phase-2 that erupted over a time span of about 250 ky. The short duration exposures of these red boles are reflected in the mineralogical and geochemical data that indicate rapid weathering (high CIA) linked to increasing acid rains. ∂D and ∂18O measured on smectite clays from the red boles approximate the meteoric water composition that prevailed during Deccan eruptions. Preliminary isotopic data from red boles deposited during the main phase-2 suggest significant and rapid changes in rainfall intensity and/or altitude linked to the accumulation of a 3100m thick basalt pile that erupted over a short period of time.
Baños, Núria; Migliorelli, Federico; Posadas, Eduardo; Ferreri, Janisse; Palacio, Montse
2015-01-01
The objectives of this review were to identify the predictive factors of induction of labor (IOL) failure or success as well as to highlight the current heterogeneity regarding the definition and diagnosis of failed IOL. Only studies in which the main or secondary outcome was failed IOL, defined as not entering the active phase of labor after 24 h of prostaglandin administration ± 12 h of oxytocin infusion, were included in the review. The data collected were: study design, definition of failed IOL, induction method, IOL indications, failed IOL rate, cesarean section because of failed IOL and predictors of failed IOL. The database search detected 507 publications. The main reason for exclusion was that the primary or secondary outcomes were not the predetermined definition of failed IOL (not achieving active phase of labor). Finally, 7 studies were eligible. The main predictive factors identified in the review were cervical status, evaluated by the Bishop score or cervical length. Failed IOL should be defined as the inability to achieve the active phase of labor, considering that the definition of IOL is to enter the active phase of labor. A universal definition of failed IOL is an essential requisite to analyze and obtain solid results and conclusions on this issue. An important finding of this review is that only 7 of all the studies reviewed assessed achieving the active phase of labor as a primary or secondary IOL outcome. Another conclusion is that cervical status remains the most important predictor of IOL outcome, although the value of the parameters explored up to now is limited. To find or develop predictive tools to identify those women exposed to IOL who may not reach the active phase of labor is crucial to minimize the risks and costs associated with IOL failure while opening a great opportunity for investigation. Therefore, other predictive tools should be studied in order to improve IOL outcome in terms of health and economic burden. © 2015 S. Karger AG, Basel.
Ahrens, W; Greiser, H; Linseisen, J; Kluttig, A; Schipf, S; Schmidt, B; Günther, K
2014-11-01
The German National Cohort (GNC) is the largest population-based cohort study in Germany. Beginning in 2014, a total of 200,000 women and men aged 20-69 years will be examined in 18 study centers. The aim of the study is to investigate the etiology of chronic diseases in relation to lifestyle, genetic, socioeconomic, and environmental factors and to develop appropriate methods for early diagnosis and prevention of diseases such as cardiovascular and respiratory diseases, cancer, diabetes, neurodegenerative/psychiatric diseases, as well as musculoskeletal and infectious diseases. Pretest studies (phase 1 and 2) were conducted to select methods, instruments, and procedures for the main study, to develop standard operating procedures, and to design and test the examination program according to acceptance, expected duration, and feasibility. The pretest studies included testing of interviews, questionnaires, anthropometric measurements, several medical examinations, and the collection of biosamples. In addition, the logistic, technical, and personnel infrastructure for the main study could be established including the study centers, the central infrastructure for data management, processes to coordinate the study, and data protection and quality management concepts. The examination program for the main phase of the GNC was designed and optimized based on the results of the pretest studies. The GNC is a population-based, highly standardized and excellently phenotyped cohort that will be the basis for new strategies for risk assessment and identification, early diagnosis, and prevention of multifactorial diseases.
Nobukawa, Teruyoshi; Nomura, Takanori
2016-09-05
A holographic data storage system using digital holography is proposed to record and retrieve multilevel complex amplitude data pages. Digital holographic techniques are capable of modulating and detecting complex amplitude distribution using current electronic devices. These techniques allow the development of a simple, compact, and stable holographic storage system that mainly consists of a single phase-only spatial light modulator and an image sensor. As a proof-of-principle experiment, complex amplitude data pages with binary amplitude and four-level phase are recorded and retrieved. Experimental results show the feasibility of the proposed holographic data storage system.
High Speed Solid State Circuit Breaker
NASA Technical Reports Server (NTRS)
Podlesak, Thomas F.
1993-01-01
The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.
Cookey, Jacob; Bernier, Denise; Tibbo, Philip G
2014-07-01
The impact of cannabis use on the brain tissue is still unclear, both in the healthy developing brain and in people with schizophrenia. The focus of this review is on white matter, the primary connective infrastructure of the brain. We systematically reviewed diffusion tensor imaging (DTI) studies of early phase schizophrenia (illness effect), of cannabis use in otherwise healthy brains (drug effect), and of early phase schizophrenia with cannabis use (combined effects). Studies had to include a healthy, non-cannabis using, control group as well as report on fractional anisotropy as it is the most commonly used DTI index. We excluded cohorts with heavy alcohol or illicit drug use and studies with a sample size of less than 20 in the clinical group. We retained 17 studies of early phase schizophrenia, which together indicate deficits in white matter integrity observed in all fiber tract families, but most frequently in association, callosal and projection fibers. In otherwise healthy cannabis users (2 studies), deficits in white matter tracts were reported mainly in callosal fibers, but also in projection and limbic fibers. In cannabis users with early phase schizophrenia (1 study), deficits in white matter integrity were also observed in all fiber tract families, except for limbic fibers. The current literature points to several families of white matter tracts being differentially affected in early phase schizophrenia. Further work is required to reveal the impact of cannabis use in otherwise healthy people as well as those with schizophrenia. Paucity of available studies as well as restricting analysis to FA values represent the main limitations of this review. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Chen, Yongzhou; Zhang, Yong; Song, Xiaozhen; Shen, Ziqin; Zhang, Tianyuan
2018-05-01
Ferroelectric glass-ceramics, with a basic composition 90 wt.% (Ba0.65Sr0.35)TiO3-10 wt.% (B2O3-nSiO2) (n = 0.5, 1, 3, 5) were synthesized by the sol-gel method and their phase development and dielectric properties were investigated by differential thermal analysis, x-ray diffraction, field emission scanning electron microscopy, dielectric temperature curves and impedance spectroscopy. From the differential thermal analysis, glass transition and crystallization behavior can be observed. From the x-ray diffraction study, two crystalline phases (Ba,Sr)TiO3 and Ba2TiSi2O8 were formed over the entire composition range of the glass-ceramics. In addition, the main crystal phase has undergone a transformation from (Ba,Sr)TiO3 to Ba2TiSi2O8 with the increase of n. A typical structure in which the crystal phase was surrounded by a glassy matrix has been observed in the scanning electron microscope images. As a result of temperature dependent dielectric property measurements, the dielectric constant increased obviously with the increase of n from 0.5 to 1. Further increasing n led to a reduction of the dielectric constant, which is in coincidence with the variation of the intensity of (Ba,Sr)TiO3 phase with n. According to the impedance spectroscopy analysis and the activation energy calculation, the relaxation peak in both Z″ and M″ data should be attributed to the crystal-glass interface, and the change of conduction mechanism with the increase of SiO2/B2O3 ratio may be attributed to the corresponding transition of the main crystal phase.
Erratum: Voyager Color Photometry of Saturn's Main Rings
NASA Technical Reports Server (NTRS)
Estrada, Paul R.; Cuzzi, Jeffrey N.; Showalter, Mark R.; DeVincenzi, Donald (Technical Monitor)
2002-01-01
We correct a calibration error in our earlier analysis of Voyager color observations of Saturn's main rings at 14 deg phase angle and present thoroughly revised and reanalyzed radial profiles of the brightness of the main rings in Voyager G, V, and UV filters, and ratios of these brightnesses. These results are consistent with more recent HST results at 6 deg phase angle, once allowance is made for plausible phase reddening of the rings. Unfortunately, the Voyager camera calibration factors are simply not sufficiently well known for a combination of the Voyager and HST data to be used to constrain the phase reddening quantitatively. However, some interesting radial variations in reddening between 6-14 deg phase angles are hinted at. We update a ring-and-satellite color vs. albedo plot from Cuzzi and Estrada in several ways. The A and B rings are still found to be in a significantly redder part of color-albedo space than Saturn's icy satellites.
Bioactive Wollastonite-Diopside Foams from Preceramic Polymers and Reactive Oxide Fillers
Fiocco, Laura; Elsayed, Hamada; Ferroni, Letizia; Gardin, Chiara; Zavan, Barbara; Bernardo, Enrico
2015-01-01
Wollastonite (CaSiO3) and diopside (CaMgSi2O6) silicate ceramics have been widely investigated as highly bioactive materials, suitable for bone tissue engineering applications. In the present paper, highly porous glass-ceramic foams, with both wollastonite and diopside as crystal phases, were developed from the thermal treatment of silicone polymers filled with CaO and MgO precursors, in the form of micro-sized particles. The foaming was due to water release, at low temperature, in the polymeric matrix before ceramic conversion, mainly operated by hydrated sodium phosphate, used as a secondary filler. This additive proved to be “multifunctional”, since it additionally favored the phase development, by the formation of a liquid phase upon firing, in turn promoting the ionic interdiffusion. The liquid phase was promoted also by the incorporation of powders of a glass crystallizing itself in wollastonite and diopside, with significant improvements in both structural integrity and crushing strength. The biological characterization of polymer-derived wollastonite-diopside foams, to assess the bioactivity of the samples, was performed by means of a cell culture test. The MTT assay and LDH activity tests gave positive results in terms of cell viability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Babic, Miroslav; Kljenak, Ivo; Mavko, Borut
2006-07-01
The CFD code CFX4.4 was used to simulate an experiment in the ThAI facility, which was designed for investigation of thermal-hydraulic processes during a severe accident inside a Light Water Reactor containment. In the considered experiment, air was initially present in the vessel, and helium and steam were injected during different phases of the experiment at various mass flow rates and at different locations. The main purpose of the proposed work was to assess the capabilities of the CFD code to reproduce the atmosphere structure with a three-dimensional model, coupled with condensation models proposed by the authors. A three-dimensional modelmore » of the ThAI vessel for the CFX4.4 code was developed. The flow in the simulation domain was modeled as single-phase. Steam condensation on vessel walls was modeled as a sink of mass and energy using a correlation that was originally developed for an integral approach. A simple model of bulk phase change was also included. Calculated time-dependent variables together with temperature and volume fraction distributions at the end of different experiment phases are compared to experimental results. (authors)« less
NASA Astrophysics Data System (ADS)
Lytvynenko, D. M.; Slyusarenko, Yu V.
2017-08-01
A theory of quasi-neutral equilibrium states of charges above a liquid dielectric surface is developed. This theory is based on the first principles of quantum statistics for systems comprising many identical particles. The proposed approach involves applying the variational principle, modified for the considered systems, and the Thomas-Fermi model. In the terms of the developed theory self-consistency equations are obtained. These equations provide the relation between the main parameters describing the system: the potential of the static electric field, the distribution function of charges and the surface profile of the liquid dielectric. The equations are used to study the phase transition in the system to a spatially periodic state. The proposed method can be applied in analyzing the properties of the phase transition in the system in relation to the spatially periodic states of wave type. Using the analytical and numerical methods, we perform a detailed study of the dependence of the critical parameters of such a phase transition on the thickness of the liquid dielectric film. Some stability criteria for the new asymmetric phase of the studied system are discussed.
Scattering - a probe to Earth's small scale structure
NASA Astrophysics Data System (ADS)
Rost, S.; Earle, P.
2009-05-01
Much of the short-period teleseismic wavefield shows strong evidence for scattered waves in extended codas trailing the main arrivals predicted by ray theory. This energy mainly originates from high-frequency body waves interacting with fine-scale volumetric heterogeneities in the Earth. Studies of this energy revealed much of what we know about Earth's structure at scale lengths around 10 km throughout the Earth from crust to core. From these data we can gain important information about the mineral-physical and geochemical constitution of the Earth that is inaccessible to many other seismic imaging techniques. Previous studies used scattered energy related to PKP, PKiKP, and Pdiff to identify and map the small-scale structure of the mantle and core. We will present observations related to the core phases PKKP and P'P' to study fine-scale mantle heterogeneities. These phases are maximum travel-time phases with respect to perturbations at their reflection points. This allows observation of the scattered energy as precursors to the main phase avoiding common problems with traditional coda phases which arrive after the main pulse. The precursory arrival of the scattered energy allows the separation between deep Earth and crustal contributions to the scattered wavefield for certain source-receiver configurations. Using the information from these scattered phases we identify regions of the mantle that shows increased scattering potential likely linked to larger scale mantle structure identified in seismic tomography and geodynamical models.
Low-noise front-end electronics for detection of intermediate-frequency weak light signals
NASA Astrophysics Data System (ADS)
Lin, Cunbao; Yan, Shuhua; Du, Zhiguang; Wei, Chunhua; Wang, Guochao
2015-02-01
A novel low-noise front-end electronics was proposed for detection of light signals with intensity about 10 μW and frequency above 2.7 MHz. The direct current (DC) power supply, pre-amplifier and main-amplifier were first designed, simulated and then realized. Small-size components were used to make the power supply small, and the pre-amplifier and main-amplifier were the least capacitors to avoid the phase shift of the signals. The performance of the developed front-end electronics was verified in cross-grating diffraction experiments. The results indicated that the output peak-topeak noise of the +/-5 V DC power supply was about 2 mV, and the total output current was 1.25 A. The signal-to-noise ratio (SNR) of the output signal of the pre-amplifier was about 50 dB, and it increased to nearly 60 dB after the mainamplifier, which means this front-end electronics was especially suitable for using in the phase-sensitive and integrated precision measurement systems.
Sensitive ultrasonic vibrometer for very low frequency applications.
Cretin, B; Vairac, P; Jachez, N; Pergaud, J
2007-08-01
Ultrasonic measurement of distance is a well-known low cost method but only a few vibrometers have been developed because sensitivity, spatial resolution, and bandwidth are not high or wide enough for standard laboratory applications. Nevertheless, compared to optical vibrometers, two interesting properties should be considered: very low frequency noise (0.1 Hz to 1 kHz) is reduced and the long wavelength enables rough surfaces to be investigated. Moreover, the ultrasonic probe is a differential sensor, without being a mechanical load for the vibrating structure as usual accelerometers based on contacting transducers are. The main specificity of the presented probe is its ultralow noise electronics including a 3/2 order phase locked loop which extracts the phase modulation related to the amplitude of the detected vibration. This article presents the main useful physical aspects and details of the actual probe. The given application is the measurement of the vibration of an isolated optical bench excited at very low frequency with an electromagnetic transducer.
Closed Loop Two-Phase Thermosyphon of Small Dimensions: a Review of the Experimental Results
NASA Astrophysics Data System (ADS)
Franco, Alessandro; Filippeschi, Sauro
2012-06-01
A bibliographical review on the heat and mass transfer in gravity assisted Closed Loop Two Phase Thermosyphons (CLTPT) with channels having a hydraulic diameter of the order of some millimetres and input power below 1 kW is proposed. The available experimental works in the literature are critically analysed in order to highlight the main results and the correlation between mass flow rate and heat input in natural circulation loops. A comparison of different experimental apparatuses and results is made. It is observed that the results are very different among them and in many cases the experimental data disagree with the conventional theory developed for an imposed flow rate. The paper analyses the main differences among the experimental devices and try to understand these disagreements. From the present analysis it is evident that further systematic studies are required to generate a meaningful body of knowledge of the heat and mass transport mechanism in these devices for practical applications in cooling devices or energy systems.
NASA Astrophysics Data System (ADS)
Costantini, L.; Pioli, L.; Bonadonna, C.; Clavero, J.; Longchamp, C.
2011-03-01
Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460 years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (< 3.1 ka) is one of the best exposed and widely dispersed pyroclastic deposits, related to both fall and flow activity. The deposit is dispersed over an area of 250 km 2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phase, characterised by unstable plumes which emplaced a series of pyroclastic density currents intercalated with thin fallout layers and finally to iv) a Climactic phase forming a more sustained plume which eventually collapsed generating the final pyroclastic density currents. The deposit (fall and flow) has a minimum cumulative volume of 0.6 km 3, with the main sustained phase being associated with a VEI 4 and the flow units having a minimum estimated total volume of 0.04 km 3. The erupted material has a homogenous chemical composition but displays a remarkable variability in both textural and physical properties. The density distribution of juvenile products shows a clear bimodality characterised by two main populations: P1 and P2. Population P1 consists of highly vesicular clasts (modal density around 1000 kg m - 3 ) with mostly sub-spherical bubbles and moderately crystallised groundmass with large-sized microlites. Clasts from population P2 are poorly vesicular (modal density around 1600 kg m - 3 ) with irregular to collapsed bubbles and numerous smaller microlites. The variability of both vesicularity and microlite characteristics suggests the involvement of two magma batches with distinct pre-eruptive degassing and rising histories. Our eruption conceptual model implies the arrival of new magma (represented in the deposit by P1 clasts) into a small, outgassed magma body which was accumulated at shallow level (mainly represented by P2 clasts). A new Chaimilla-type eruption could significantly affect the communities that have recently developed around Villarrica volcano and subsist mainly on tourism and forestry. As a result, a better understanding of the dynamics and evolution of the Chaimilla eruption is necessary for the identification of potential hazard scenarios at Villarrica volcano and, ultimately, for the risk mitigation of this populated area of Southern Chile.
Software Estimates Costs of Testing Rocket Engines
NASA Technical Reports Server (NTRS)
Smith, C. L.
2003-01-01
Simulation-Based Cost Model (SiCM), a discrete event simulation developed in Extend , simulates pertinent aspects of the testing of rocket propulsion test articles for the purpose of estimating the costs of such testing during time intervals specified by its users. A user enters input data for control of simulations; information on the nature of, and activity in, a given testing project; and information on resources. Simulation objects are created on the basis of this input. Costs of the engineering-design, construction, and testing phases of a given project are estimated from numbers and labor rates of engineers and technicians employed in each phase, the duration of each phase; costs of materials used in each phase; and, for the testing phase, the rate of maintenance of the testing facility. The three main outputs of SiCM are (1) a curve, updated at each iteration of the simulation, that shows overall expenditures vs. time during the interval specified by the user; (2) a histogram of the total costs from all iterations of the simulation; and (3) table displaying means and variances of cumulative costs for each phase from all iterations. Other outputs include spending curves for each phase.
Wyoming freight movement system vulnerabilities and ITS.
DOT National Transportation Integrated Search
2013-12-01
This report summarizes the work performed during the second phase of a two-phase : research project. The first phase focused on two main areas: freight safety and wind : vulnerability, and the identification of critical infrastructure. Phase I also t...
Influence of control parameters on the joint tracking performance of a coaxial weld vision system
NASA Technical Reports Server (NTRS)
Gangl, K. J.; Weeks, J. L.
1985-01-01
The first phase of a series of evaluations of a vision-based welding control sensor for the Space Shuttle Main Engine Robotic Welding System is described. The robotic welding system is presently under development at the Marshall Space Flight Center. This evaluation determines the standard control response parameters necessary for proper trajectory of the welding torch along the joint.
X-48B Phase 1 Flight Maneuver Database and ICP Airspace Constraint Analysis
NASA Technical Reports Server (NTRS)
Fast, Peter Alan
2010-01-01
The work preformed during the Summer 2010 by Peter Fast. The main tasks assigned were to update and improve the X-48 Flight Maneuver Database and conduct an Airspace Constraint Analysis for the Remotely Operated Aircraft Area used to flight test Unmanned Arial Vehicles. The final task was to develop and demonstrate a working knowledge of flight control theory.
NASA Astrophysics Data System (ADS)
Huang, Peiyan; Liu, Guangwan; Guo, Xinyan; Huang, Man
2008-11-01
The experimental research on fatigue crack propagation rate of reinforced concrete (RC) beams strengthened with carbon fiber laminate (CFL) is carried out by MTS system in this paper. The experimental results show that, the main crack propagation on strengthened beam can be summarized into three phases: 1) fast propagation phase; 2) steady propagation and rest phase; 3) unsteady propagation phase. The phase 2-i.e. steady propagation and rest stage makes up about 95% of fatigue life of the strengthened beam. The propagation rate of the main crack, da/dN, in phase 2 can be described by Paris formula, and the constant C and m can be confirmed by the fatigue crack propagation experiments of the RC beams strengthened with CFL under three-point bending loads.
On the phase lag of turbulent dissipation in rotating tidal flows
NASA Astrophysics Data System (ADS)
Zhang, Qianjiang; Wu, Jiaxue
2018-03-01
Field observations of rotating tidal flows in a shallow tidally swept sea reveal that a notable phase lag of both shear production and turbulent dissipation increases with height above the seafloor. These vertical delays of turbulent quantities are approximately equivalent in magnitude to that of squared mean shear. The shear production approximately equals turbulent dissipation over the phase-lag column, and thus a main mechanism of phase lag of dissipation is mean shear, rather than vertical diffusion of turbulent kinetic energy. By relating the phase lag of dissipation to that of the mean shear, a simple formulation with constant eddy viscosity is developed to describe the phase lag in rotating tidal flows. An analytical solution indicates that the phase lag increases linearly with height subjected to a combined effect of tidal frequency, Coriolis parameter and eddy viscosity. The vertical diffusion of momentum associated with eddy viscosity produces the phase lag of squared mean shear, and resultant delay of turbulent quantities. Its magnitude is inhibited by Earth's rotation. Furthermore, a theoretical formulation of the phase lag with a parabolic eddy viscosity profile can be constructed. A first-order approximation of this formulation is still a linear function of height, and its magnitude is approximately 0.8 times that with constant viscosity. Finally, the theoretical solutions of phase lag with realistic viscosity can be satisfactorily justified by realistic phase lags of dissipation.
Rolfe, Matthew D.; Rice, Christopher J.; Lucchini, Sacha; Pin, Carmen; Thompson, Arthur; Cameron, Andrew D. S.; Alston, Mark; Stringer, Michael F.; Betts, Roy P.; Baranyi, József; Peck, Michael W.
2012-01-01
Lag phase represents the earliest and most poorly understood stage of the bacterial growth cycle. We developed a reproducible experimental system and conducted functional genomic and physiological analyses of a 2-h lag phase in Salmonella enterica serovar Typhimurium. Adaptation began within 4 min of inoculation into fresh LB medium with the transient expression of genes involved in phosphate uptake. The main lag-phase transcriptional program initiated at 20 min with the upregulation of 945 genes encoding processes such as transcription, translation, iron-sulfur protein assembly, nucleotide metabolism, LPS biosynthesis, and aerobic respiration. ChIP-chip revealed that RNA polymerase was not “poised” upstream of the bacterial genes that are rapidly induced at the beginning of lag phase, suggesting a mechanism that involves de novo partitioning of RNA polymerase to transcribe 522 bacterial genes within 4 min of leaving stationary phase. We used inductively coupled plasma mass spectrometry (ICP-MS) to discover that iron, calcium, and manganese are accumulated by S. Typhimurium during lag phase, while levels of cobalt, nickel, and sodium showed distinct growth-phase-specific patterns. The high concentration of iron during lag phase was associated with transient sensitivity to oxidative stress. The study of lag phase promises to identify the physiological and regulatory processes responsible for adaptation to new environments. PMID:22139505
Development of dual sensor hand-held detector
NASA Astrophysics Data System (ADS)
Sezgin, Mehmet
2010-04-01
In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.
Development/Modernization of an Advanced Non-Light Water Reactor Probabilistic Risk Assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henneke, Dennis W.; Robinson, James
In 2015, GE Hitachi Nuclear Energy (GEH) teamed with Argonne National Laboratory (Argonne) to perform Research and Development (R&D) of next-generation Probabilistic Risk Assessment (PRA) methodologies for the modernization of an advanced non-Light Water Reactor (non-LWR) PRA. This effort built upon a PRA developed in the early 1990s for GEH’s Power Reactor Inherently Safe Module (PRISM) Sodium Fast Reactor (SFR). The work had four main tasks: internal events development modeling the risk from the reactor for hazards occurring at-power internal to the plant; an all hazards scoping review to analyze the risk at a high level from external hazards suchmore » as earthquakes and high winds; an all modes scoping review to understand the risk at a high level from operating modes other than at-power; and risk insights to integrate the results from each of the three phases above. To achieve these objectives, GEH and Argonne used and adapted proven PRA methodologies and techniques to build a modern non-LWR all hazards/all modes PRA. The teams also advanced non-LWR PRA methodologies, which is an important outcome from this work. This report summarizes the project outcomes in two major phases. The first phase presents the methodologies developed for non-LWR PRAs. The methodologies are grouped by scope, from Internal Events At-Power (IEAP) to hazards analysis to modes analysis. The second phase presents details of the PRISM PRA model which was developed as a validation of the non-LWR methodologies. The PRISM PRA was performed in detail for IEAP, and at a broader level for hazards and modes. In addition to contributing methodologies, this project developed risk insights applicable to non-LWR PRA, including focus-areas for future R&D, and conclusions about the PRISM design.« less
Lesellier, E
2012-11-30
The recent introduction of new stationary phases for liquid chromatography based on superficially porous particles, called core-shell or fused-core, dramatically improved the separation performances through very high efficiency, due mainly to reduced eddy diffusion. However, few studies have evaluated the retention and selectivity of C18 phases based on such particles, despite some retention order change reported in literature between some of these phases. The carotenoid test has been developed a few years ago in the goal to compare the chromatographic properties of C18 bonded phases. Based on the analysis of carotenoid pigments by using Supercritical Fluid Chromatography (SFC), it allows, with a single analysis, to measure three main properties of reversed phase chromatography stationary phases: hydrophobicity, polar surface activity and shape selectivity. Previous studies showed the effect of the endcapping treatment, the bonding density, the pore size, and the type of bonding (monomeric vs. polymeric) on these studied properties, and described the classification map used for a direct column comparison. It was applied to ten ODS superficially porous stationary phases, showing varied chromatographic behaviors amongst these phases. As expected, due to the lower specific surface area, these superficially porous phases are less hydrophobic than the fully porous one. In regards of the polar surface activity (residual silanols) and to the shape selectivity, some of these superficially porous phases display close chromatographic properties (Poroshell 120, Halo C18, Ascentis Express, Accucore C18, Nucleoshell C18 on one side and Aeris Wide pore, Aeris peptide and Kinetex XDB on the other side), whereas others, Kinetex C18 and Halo peptide ES C18 display more specific ones. Besides, they can be compared to classical fully porous phases, in the goal to improve method transfer from fully to superficially porous particles. By the way, the paper also report the extension of the test to other ligands such as naphtyl, cholester, phenyl-hexyl, or to the new ODS bonded phases, such as charge surface hybrid phases, High Strength Silica, and Hybrid ones, and also presents results for identical brands using different particle size, such as Luna and Synergi phases. Phenyl-hexyl and napthyl ligands show rather close properties, low hydrophobicity, high polar surface activity and specific shape selectivity, whereas, at the opposite, the cholester phase display a polymeric behavior and a high hydrophobicity. Finally, additional classical (fully porous particles) C18 bonded phases are also reported to complete the data set presented in previous papers. Copyright © 2012 Elsevier B.V. All rights reserved.
Carbon Nanotube Chopped Fiber for Enhanced Properties in Additive Manufacturing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Menchhofer, Paul A.; Johnson, Joseph E.; Lindahl, John M.
2016-06-06
Nanocomp Technologies, Inc. is working with Oak Ridge National Laboratory to develop carbon nanotube (CNT) composite materials and evaluate their use in additive manufacturing (3D printing). The first phase demonstrated feasibility and improvements for carbon nanotube (CNT)- acrylonitrile butadiene styrene (ABS) composite filaments use in additive manufacturing, with potential future work centering on further improvements. By focusing the initial phase on standard processing methods (developed mainly for the incorporation of carbon fibers in ABS) and characterization techniques, a basis of knowledge for the incorporation of CNTs in ABS was learned. The ability to understand the various processing variables is criticalmore » to the successful development of these composites. From the degradation effects on ABS (caused by excessive temperatures), to the length of time the ABS is in the melt state, to the order of addition of constituents, and also to the many possible mixing approaches, a workable flow sequence that addresses each processing step is critical to the final material properties. Although this initial phase could not deal with each of these variables in-depth, a future study is recommended that will build on the lessons learned for this effort.« less
Development of a S/w System for Relative Positioning Using GPS Carrier Phase
NASA Astrophysics Data System (ADS)
Ahn, Yong-Won; Kim, Chun-Hwey; Park, Pil-Ho; Park, Jong-Uk; Jo, Jeong-Ho
1997-12-01
We developed a GPS phase data processing S/W system which calculates baseline vectors and distances between two points located in the surface of the Earth. For this development a Double-Difference method and L1 carrier phase data from GPS(Global Positioning System) were used. This S/W system consists of four main parts : satellite position calculation, Single-Difference equation, Double-Difference equation, and correlation. To verify our S/W, we fixed KAO(N36.37, E127.37, H77.61m), one of the International GPS Services for Geodynamics, which is located at Tae-Jon, and we measured baseline vectors and relative distances with data from observations at approximate baseline distances of 2.7, 42.1, 81.1, 146.6km. Then we compared the vectors and distances with the data which we obtained from the GPSurvery S/W system, with the L1/L2 ION-Free method and broadcast ephemeris. From the comparison of the vectors and distances with the data from the GPSurvey S/W system, we found baseline vectors X, Y, Z and baseline distances matched well within the extent of 50cm and 10cm, respectively.
O'Ryan, Miguel; Vidal, Roberto; del Canto, Felipe; Salazar, Juan Carlos; Montero, David
2015-01-01
Efforts to develop vaccines for prevention of acute diarrhea have been going on for more than 40 y with partial success. The myriad of pathogens, more than 20, that have been identified as a cause of acute diarrhea throughout the years pose a significant challenge for selecting and further developing the most relevant vaccine candidates. Based on pathogen distribution as identified in epidemiological studies performed mostly in low-resource countries, rotavirus, Cryptosporidium, Shigella, diarrheogenic E. coli and V. cholerae are predominant, and thus the main targets for vaccine development and implementation. Vaccination against norovirus is most relevant in middle/high-income countries and possibly in resource-deprived countries, pending a more precise characterization of disease impact. Only a few licensed vaccines are currently available, of which rotavirus vaccines have been the most outstanding in demonstrating a significant impact in a short time period. This is a comprehensive review, divided into 2 articles, of nearly 50 vaccine candidates against the most relevant viral and bacterial pathogens that cause acute gastroenteritis. In order to facilitate reading, sections for each pathogen are organized as follows: i) a discussion of the main epidemiological and pathogenic features; and ii) a discussion of vaccines based on their stage of development, moving from current licensed vaccines to vaccines in advanced stage of development (in phase IIb or III trials) to vaccines in early stages of clinical development (in phase I/II) or preclinical development in animal models. In this first article we discuss rotavirus, norovirus and Vibrio cholerae. In the following article we will discuss Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic), and Campylobacter jejuni.
O’Ryan, Miguel; Vidal, Roberto; del Canto, Felipe; Salazar, Juan Carlos; Montero, David
2015-01-01
Efforts to develop vaccines for prevention of acute diarrhea have been going on for more than 40 y with partial success. The myriad of pathogens, more than 20, that have been identified as a cause of acute diarrhea throughout the years pose a significant challenge for selecting and further developing the most relevant vaccine candidates. Based on pathogen distribution as identified in epidemiological studies performed mostly in low-resource countries, rotavirus, Cryptosporidium, Shigella, diarrheogenic E. coli and V. cholerae are predominant, and thus the main targets for vaccine development and implementation. Vaccination against norovirus is most relevant in middle/high-income countries and possibly in resource-deprived countries, pending a more precise characterization of disease impact. Only a few licensed vaccines are currently available, of which rotavirus vaccines have been the most outstanding in demonstrating a significant impact in a short time period. This is a comprehensive review, divided into 2 articles, of nearly 50 vaccine candidates against the most relevant viral and bacterial pathogens that cause acute gastroenteritis. In order to facilitate reading, sections for each pathogen are organized as follows: i) a discussion of the main epidemiological and pathogenic features; and ii) a discussion of vaccines based on their stage of development, moving from current licensed vaccines to vaccines in advanced stage of development (in phase IIb or III trials) to vaccines in early stages of clinical development (in phase I/II) or preclinical development in animal models. In this first article we discuss rotavirus, norovirus and Vibrio cholerae. In the following article we will discuss Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic), and Campylobacter jejuni. PMID:25715048
Housing decision making methods for initiation development phase process
NASA Astrophysics Data System (ADS)
Zainal, Rozlin; Kasim, Narimah; Sarpin, Norliana; Wee, Seow Ta; Shamsudin, Zarina
2017-10-01
Late delivery and sick housing project problems were attributed to poor decision making. These problems are the string of housing developer that prefers to create their own approach based on their experiences and expertise with the simplest approach by just applying the obtainable standards and rules in decision making. This paper seeks to identify the decision making methods for housing development at the initiation phase in Malaysia. The research involved Delphi method by using questionnaire survey which involved 50 numbers of developers as samples for the primary stage of collect data. However, only 34 developers contributed to the second stage of the information gathering process. At the last stage, only 12 developers were left for the final data collection process. Finding affirms that Malaysian developers prefer to make their investment decisions based on simple interpolation of historical data and using simple statistical or mathematical techniques in producing the required reports. It was suggested that they seemed to skip several important decision-making functions at the primary development stage. These shortcomings were mainly due to time and financial constraints and the lack of statistical or mathematical expertise among the professional and management groups in the developer organisations.
Chen, Chung-De; Huang, Yen-Chieh; Chiang, Hsin-Lin; Hsieh, Yin-Cheng; Guan, Hong-Hsiang; Chuankhayan, Phimonphan; Chen, Chun-Jung
2014-09-01
Optimization of the initial phasing has been a decisive factor in the success of the subsequent electron-density modification, model building and structure determination of biological macromolecules using the single-wavelength anomalous dispersion (SAD) method. Two possible phase solutions (φ1 and φ2) generated from two symmetric phase triangles in the Harker construction for the SAD method cause the well known phase ambiguity. A novel direct phase-selection method utilizing the θ(DS) list as a criterion to select optimized phases φ(am) from φ1 or φ2 of a subset of reflections with a high percentage of correct phases to replace the corresponding initial SAD phases φ(SAD) has been developed. Based on this work, reflections with an angle θ(DS) in the range 35-145° are selected for an optimized improvement, where θ(DS) is the angle between the initial phase φ(SAD) and a preliminary density-modification (DM) phase φ(DM)(NHL). The results show that utilizing the additional direct phase-selection step prior to simple solvent flattening without phase combination using existing DM programs, such as RESOLVE or DM from CCP4, significantly improves the final phases in terms of increased correlation coefficients of electron-density maps and diminished mean phase errors. With the improved phases and density maps from the direct phase-selection method, the completeness of residues of protein molecules built with main chains and side chains is enhanced for efficient structure determination.
Curtis, Jeffrey R; Lee, Eun Bong; Kaplan, Irina V; Kwok, Kenneth; Geier, Jamie; Benda, Birgitta; Soma, Koshika; Wang, Lisy; Riese, Richard
2016-01-01
Objectives Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). To further assess the potential role of Janus kinase inhibition in the development of malignancies, we performed an integrated analysis of data from the tofacitinib RA clinical development programme. Methods Malignancy data (up to 10 April 2013) were pooled from six phase II, six Phase III and two long-term extension (LTE) studies involving tofacitinib. In the phase II and III studies, patients with moderate-to-severe RA were randomised to various tofacitinib doses as monotherapy or with background non-biological disease-modifying antirheumatic drugs (DMARDs), mainly methotrexate. The LTE studies (tofacitinib 5 or 10 mg twice daily) enrolled patients from qualifying prior phase I, II and III index studies. Results Of 5671 tofacitinib-treated patients, 107 developed malignancies (excluding non-melanoma skin cancer (NMSC)). The most common malignancy was lung cancer (n=24) followed by breast cancer (n=19), lymphoma (n=10) and gastric cancer (n=6). The rate of malignancies by 6-month intervals of tofacitinib exposure indicates rates remained stable over time. Standardised incidence ratios (comparison with Surveillance, Epidemiology and End Results) for all malignancies (excluding NMSC) and selected malignancies (lung, breast, lymphoma, NMSC) were within the expected range of patients with moderate-to-severe RA. Conclusions The overall rates and types of malignancies observed in the tofacitinib clinical programme remained stable over time with increasing tofacitinib exposure. PMID:25902789
Light stable isotope analysis of meteorites by ion microprobe
NASA Technical Reports Server (NTRS)
Mcsween, Harry Y., Jr.
1994-01-01
The main goal was to develop the necessary secondary ion mass spectrometer (SIMS) techniques to use a Cameca ims-4f ion microprobe to measure light stable isotope ratios (H, C, O and S) in situ and in non-conducting mineral phases. The intended application of these techniques was the analysis of meteorite samples, although the techniques that have been developed are equally applicable to the investigation of terrestrial samples. The first year established techniques for the analysis of O isotope ratios (delta O-18 and delta O-17) in conducting mineral phases and the measurement of S isotope ratios (delta S-34) in a variety of sulphide phases. In addition, a technique was developed to measure delta S-34 values in sulphates, which are insulators. Other research undertaken in the first year resulted in SIMS techniques for the measurement of wide variety of trace elements in carbonate minerals, with the aim of understanding the nature of alteration fluids in carbonaceous chondrites. In the second year we developed techniques for analyzing O isotope ratios in nonconducting mineral phases. These methods are potentially applicable to the measurement of other light stable isotopes such as H, C and S in insulators. Also, we have further explored the analytical techniques used for the analysis of S isotopes in sulphides by analyzing troilite in a number of L and H ordinary chondrites. This was done to see if there was any systematic differences with petrological type.
NASA Technical Reports Server (NTRS)
Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.
1989-01-01
The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.
Nayak, Nadiya B.; Nayak, Bibhuti B.
2016-01-01
Development of in-born porous nature of zirconium hydroxide nanopowders through a facile hydrogen (H2) gas-bubbles assisted borohydride synthesis route using sodium borohydride (NaBH4) and novel information on the temperature-mediated phase transformation, pore geometry as well as pore hysteresis transformation of in-born porous zirconium hydroxide nanopowders with the help of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) isotherm and Transmission Electron Microscopy (TEM) images are the main theme of this research work. Without any surfactants or pore forming agents, the borohydride derived amorphous nature of porous powders was stable up to 500 °C and then the seed crystals start to develop within the loose amorphous matrix and trapping the inter-particulate voids, which led to develop the porous nature of tetragonal zirconium oxide at 600 °C and further sustain this porous nature as well as tetragonal phase of zirconium oxide up to 800 °C. The novel hydrogen (H2) gas-bubbles assisted borohydride synthesis route led to develop thermally stable porous zirconium hydroxide/oxide nanopowders with an adequate pore size, pore volume, and surface area and thus these porous materials are further suggested for promising use in different areas of applications. PMID:27198738
NASA Astrophysics Data System (ADS)
Lee, Jun; Lee, Jungwoo; Yun, Sang-Leen; Oh, Hye-Cheol
2017-08-01
The purpose of this study was to develop a two-dimensional shallow water flow model using the finite volume method on a combined unstructured triangular and quadrilateral grid system to simulate coastal, estuarine and river flows. The intercell numerical fluxes were calculated using the classical Osher-Solomon's approximate Riemann solver for the governing conservation laws to be able to handle wetting and drying processes and to capture a tidal bore like phenomenon. The developed model was validated with several benchmark test problems including the two-dimensional dam-break problem. The model results were well agreed with results of other models and experimental results in literature. The unstructured triangular and quadrilateral combined grid system was successfully implemented in the model, thus the developed model would be more flexible when applying in an estuarine system, which includes narrow channels. Then, the model was tested in Mobile Bay, Alabama, USA. The developed model reproduced water surface elevation well as having overall Predictive Skill of 0.98. We found that the primary inlet, Main Pass, only covered 35% of the fresh water exchange while it covered 89% of the total water exchange between the ocean and Mobile Bay. There were also discharge phase difference between MP and the secondary inlet, Pass aux Herons, and this phase difference in flows would act as a critical role in substances' exchange between the eastern Mississippi Sound and the northern Gulf of Mexico through Main Pass and Pass aux Herons in Mobile Bay.
Enhancing seismic P phase arrival picking based on wavelet denoising and kurtosis picker
NASA Astrophysics Data System (ADS)
Shang, Xueyi; Li, Xibing; Weng, Lei
2018-01-01
P phase arrival picking of weak signals is still challenging in seismology. A wavelet denoising is proposed to enhance seismic P phase arrival picking, and the kurtosis picker is applied on the wavelet-denoised signal to identify P phase arrival. It has been called the WD-K picker. The WD-K picker, which is different from those traditional wavelet-based pickers on the basis of a single wavelet component or certain main wavelet components, takes full advantage of the reconstruction of main detail wavelet components and the approximate wavelet component. The proposed WD-K picker considers more wavelet components and presents a better P phase arrival feature. The WD-K picker has been evaluated on 500 micro-seismic signals recorded in the Chinese Yongshaba mine. The comparison between the WD-K pickings and manual pickings shows the good picking accuracy of the WD-K picker. Furthermore, the WD-K picking performance has been compared with the main detail wavelet component combining-based kurtosis (WDC-K) picker, the single wavelet component-based kurtosis (SW-K) picker, and certain main wavelet component-based maximum kurtosis (MMW-K) picker. The comparison has demonstrated that the WD-K picker has better picking accuracy than the other three-wavelet and kurtosis-based pickers, thus showing the enhanced ability of wavelet denoising.
NASA Astrophysics Data System (ADS)
Hatch, Spencer M.; LaBelle, James; Chaston, Christopher C.
2018-01-01
We review the role of Alfvén waves in magnetosphere-ionosphere coupling during geomagnetically active periods, and use three years of high-latitude FAST satellite observations of inertial Alfvén waves (IAWs) together with 55 years of tabulated measurements of the Dst index to answer the following questions: 1) How do global rates of IAW-related energy deposition, electron precipitation, and ion outflow during storm main phase and storm recovery phase compare with global rates during geomagnetically quiet periods? 2) What fraction of net IAW-related energy deposition, electron precipitation, and ion outflow is associated with storm main phase and storm recovery phase; that is, how are these budgets partitioned by storm phase? We find that during the period between October 1996 and November 1999, rates of IAW-related energy deposition, electron precipitation, and ion outflow during geomagnetically quiet periods are increased by factors of 4-5 during storm phases. We also find that ∼62-68% of the net Alfvénic energy deposition, electron precipitation, and ion outflow in the auroral ionosphere occurred during storm main and recovery phases, despite storm phases comprising only 31% of this period. In particular storm main phase, which comprised less than 14% of the three-year period, was associated with roughly a third of the total Alfvénic energy input and ion outflow in the auroral ionosphere. Measures of geomagnetic activity during the IAW study period fall near corresponding 55-year median values, from which we conclude that each storm phase is associated with a fraction of total Alfvénic energy, precipitation, and outflow budgets in the auroral ionosphere that is, in the long term, probably as great or greater than the fraction associated with geomagnetic quiescence for all times except possibly those when geomagnetic activity is protractedly weak, such as solar minimum. These results suggest that the budgets of IAW-related energy deposition, electron precipitation, and ion outflow are roughly equally partitioned by geomagnetic storm phase.
Global Pattern of The Evolutions of the Sub-Auroral Polarization Streams
NASA Astrophysics Data System (ADS)
He, F.; Zhang, X.; Wang, W.; Wan, W.
2017-12-01
Due to the spatial and temporal limitations of the in-situ measurements from the low altitude polar orbiting satellites or the ionospheric scan by incoherent scatter radars, the global configuration and evolution of SAPS are still not very clear. Here, we present multi-satellite observations of the evolution of subauroral polarization streams (SAPS) during the main phase of a server geomagnetic storm occurred on 31 March 2001. DMSP F12 to F15 observations indicate that the SAPS were first generated in the dusk sector at the beginning of the main phase. Then the SAPS channel expanded towards the midnight and moved to lower latitudes as the main phase went on. The peak velocity, latitudinal width, latitudinal alignment, and longitudinal span of the SAPS channels were highly dynamic during the storm main phase. The global evolution of the SAPS corresponds well with that of the region-2 field-aligned currents, which are mainly determined by the azimuthal pressure gradient of the ring current. Further studies on 37 storms and 30 isolated substorms indicate that the lifetime of the SAPS channel was proportional to the period of time for southward interplanetary magnetic field (IMF). The SAPS channel disappeared after northward turning of the IMF. During the recovery phase, if the IMF kept northward, no SAPS channel was generated, if the IMF turned to southward again, however, SAPS channel will be generated again with lifetime proportional to the duration of the southward IMF. During isolated substorms, the SAPS channel was also controlled by IMF. The SAPS channel was generated after substorm onset and the peak drift velocity of the SAPS channel achieved its maximum during the recovery phase of the substorm. It is suggested that, SAPS channel were mainly controlled by IMF, more works should be done with observations or simulations of investigate the global patterns of the SAPS and the magnetosphere-ionosphere couplings.
First-order system least squares and the energetic variational approach for two-phase flow
NASA Astrophysics Data System (ADS)
Adler, J. H.; Brannick, J.; Liu, C.; Manteuffel, T.; Zikatanov, L.
2011-07-01
This paper develops a first-order system least-squares (FOSLS) formulation for equations of two-phase flow. The main goal is to show that this discretization, along with numerical techniques such as nested iteration, algebraic multigrid, and adaptive local refinement, can be used to solve these types of complex fluid flow problems. In addition, from an energetic variational approach, it can be shown that an important quantity to preserve in a given simulation is the energy law. We discuss the energy law and inherent structure for two-phase flow using the Allen-Cahn interface model and indicate how it is related to other complex fluid models, such as magnetohydrodynamics. Finally, we show that, using the FOSLS framework, one can still satisfy the appropriate energy law globally while using well-known numerical techniques.
Workshop on Two-Phase Fluid Behavior in a Space Environment
NASA Technical Reports Server (NTRS)
Swanson, Theodore D. (Editor); Juhasz, AL (Editor); Long, W. Russ (Editor); Ottenstein, Laura (Editor)
1989-01-01
The Workshop was successful in achieving its main objective of identifying a large number of technical issues relating to the design of two-phase systems for space applications. The principal concern expressed was the need for verified analytical tools that will allow an engineer to confidently design a system to a known degree of accuracy. New and improved materials, for such applications as thermal storage and as heat transfer fluids, were also identified as major needs. In addition to these research efforts, a number of specific hardware needs were identified which will require development. These include heat pumps, low weight radiators, advanced heat pipes, stability enhancement devices, high heat flux evaporators, and liquid/vapor separators. Also identified was the need for a centralized source of reliable, up-to-date information on two-phase flow in a space environment.
Smith, Kevin W; Cain, Fred W; Talbot, Geoff
2004-08-25
Palm kernel stearin and hydrogenated palm kernel stearin can be used to prepare compound chocolate bars or coatings. The objective of this study was to characterize the chemical composition, polymorphism, and melting behavior of the bloom that develops on bars of compound chocolate prepared using these fats. Bars were stored for 1 year at 15, 20, or 25 degrees C. At 15 and 20 degrees C the bloom was enriched in cocoa butter triacylglycerols, with respect to the main fat phase, whereas at 25 degrees C the enrichment was with palm kernel triacylglycerols. The bloom consisted principally of solid fat and was sharper melting than was the fat in the chocolate. Polymorphic transitions from the initial beta' phase to the beta phase accompanied the formation of bloom at all temperatures.
Koehler, Annette; Wildbolz, Caroline
2009-11-15
An in-depth life-cycle assessment of nine home-care and personal-hygiene products was conducted to determine the ecological relevance of different life-cycle phases and compare the environmental profiles of products serving equal applications. Using detailed data from industry and consumer-behavior studies a broad range of environmental impacts were analyzed to identify the main drivers in each life-cycle stage and potentials for improving the environmental footprints. Although chemical production significantly adds to environmental burdens, substantial impacts are caused in the consumer-use phase. As such, this research provides recommendations for product development, supply chain management, product policies, and consumer use. To reduce environmental burdens products should, for instance, be produced in concentrated form, while consumers should apply correct product dosages and low water temperatures during product application.
Some characteristics of intense geomagnetic storms and their energy budget
NASA Astrophysics Data System (ADS)
Vichare, Geeta; Alex, S.; Lakhina, G. S.
2005-03-01
The present study analyses nine intense geomagnetic storms (∣Dst∣ > 175 nT) with the aid of ACE satellite measurements and ground magnetic field values at Alibag Magnetic Observatory. The study confirms the crucial role of southward IMF in triggering the storm main phase as well as controlling the magnitude of the storm. The main phase interval shows clear dependence on the duration of southward IMF. An attempt is made to identify the multipeak signature in the ring current energy injection rate during main phase of the storm. In order to quantify the energy budget of magnetic storms, the present paper computes the solar wind energies, magnetospheric coupling energies, auroral and Joule heating energies, and the ring current energies for each storm under examination. Computation of the solar wind- magnetosphere coupling function considers the variation of the size of the magnetosphere by using the measured solar wind ram pressure. During the main phase of the storm, the solar wind kinetic energy ranges from 9 × 1017 to 72 × 1017 J with an average of 30 × 1017 J; the total energy dissipated in the auroral ionosphere varies between 2 × 1015 and 9 × 1015 J, whereas ring current energies range from 8 × 1015 to 19 × 1015 J. For the total storm period, about 3.5% of total solar wind kinetic energy is available for the redistribution in the magnetosphere, and around 20% of this goes into the inner magnetosphere and in the auroral ionosphere of both the hemispheres. It is found that during main phase of the storm, almost 5% of the total solar wind kinetic energy is available for the redistribution in the magnetosphere, whereas during the recovery phase the percentage becomes 2.3%.
Is there a maternally induced immunological imprinting phase à la Konrad Lorenz?
Lemke, H; Lange, H
1999-10-01
In mammals, IgG antibodies are transferred from mothers to the offspring. Since these maternal antibodies result mainly from thymus-dependent immune responses which have undergone immune maturation through somatic hypermutations, they represent the highest quality of the collective maternal immunological experience. Maternal antibodies not only confer passive immunity as long as the newborn's immune system has not fully developed, but also exert an active stimulation as indicated by their regulatory influence on isotype expression, long-term idiotypic alterations, determination of the adult B and T cell repertoire, induction of antigen reactive IgM as well as an affinity enhancement of a proportion of early primary antibodies. The fact that several of these features can only be induced during limited sensitive periods shortly after birth is reminiscent of the behavioural imprinting as defined by Konrad Lorenz. We therefore propose that during early ontogeny there is an immunological imprinting phase with characteristics analogous to behavioural imprinting: (i) the internal imprinting effect is induced by external signals, (ii) in contrast to normal learning, immunological imprinting is also only possible during certain development phases and (iii) it is characterised by an (almost) irreversible result. Hence, if particular immunological experiences are only possible during such sensitive phases, maternal immunoglobulins and consequently the mother's immunological experience is of prime importance for the start of the ontogenetic development of the immune system.
Distribution of PAEs in the middle and lower reaches of the Yellow River, China.
Sha, Yujuan; Xia, Xinghui; Yang, Zhifeng; Huang, Gordon H
2007-01-01
Samples of water, sediment and suspended particulates were collected from 13 sites in the middle and lower reaches of the Yellow River in China. Phthalic acid esters (PAEs) concentrations in different phases of each sample were determined by Gas Chromatogram GC-FID. The results are shown as follows: (1) In the Xiao Langdi-Dongming Bridge section, PAEs concentrations in water phase from the main river ranged from 3.99 x 10(-3) to 45.45 x 10(-3) mg/L, which were similar to those from other rivers in the world. The PAEs levels in the tributaries of the Yellow River were much higher than those of the main river. (2) In the studied branches, the concentration of PAEs in sediment for Luoyang Petrochemical Channel (331.70 mg/Kg) was the highest. The concentrations of PAEs in sediment phase of the main river were 30.52 to 85.16 mg/Kg, which were much higher than those from other rivers in the world. In the main river, the concentration level of PAEs on suspended solid phases reached 94.22 mg/Kg, and it reached 691.23 mg/Kg in the Yiluo River - one tributary of the Yellow River. (3) Whether in the sediment or on the suspended solid phases, there was no significant correlation between the contents of PAEs and TOC or particle size of the solid phase; and the calculated Koc of Di (2-Ethylhexyl) Phthalate (DEHP) in the river were much less than the theoretical value, which inferred that PAEs were not on the equilibrium between water and suspended solid phases/sediment. (4) Among the measured PAEs compounds, the proportions of DEHP and di-n-butyl phthalate (DBP) were much higher than the others. The concentrations of DEHP exceeded the Quality Standard in all the main river and tributary stations except those in the Mengjin and Jiaogong Bridge of the main river. This indicates that more attention should be paid to pollution control and further assessment in understanding risks associated with human health.
Survey of minor-to-moderate magnetic storm effects on ionosphere: American sector
NASA Astrophysics Data System (ADS)
Buresova, Dalia; Lastovicka, Jan; Chum, Jaroslav; Pezzopane, Michael; Staciarini Batista, Inez; Gularte, Erika; Novotna, Dagmar
2014-05-01
The paper is focused on ionospheric reaction to occasional minor-to-moderate magnetic storms above selected ionospheric stations located across the Northern and Southern America. Most of the storms analysed occurred under extremely low solar activity conditions of 2007-2009. We analysed variability of the F2 layer critical frequency foF2 and the F2 layer peak height hmF2 obtained for different latitudinal and longitudinal sectors of both hemispheres for the entire period of selected magnetic storms. Observations were compared with the effects of strong magnetic storms and with the IRI2000 outputs when STORM model option is activated. We analysed ionospheric reaction during each storm phase with main emphasis paid on the recovery phase. In general, storm recovery phase is characterized by an abatement of perturbations and a gradual return to the "ground state" of ionosphere. Magnetospheric substorms, typical for the main phase, as a rule cease during the storm recovery phase. However, observations of stormy ionosphere show significant departures from the climatology also within this phase, which are comparable with those usually observed during the storm main phase. Both positive and negative deviations of foF2 and hmF2 have been observed independent on season and location.
NASA Astrophysics Data System (ADS)
Li, Zhu-bai; Wang, Li-chen; Geng, Xiao-peng; Hu, Feng-xia; Sun, Ji-rong; Shen, Bao-gen
2017-03-01
Magnetic materials of MM-Fe-B (MM=mischmetal) ribbons were prepared using melt spinning method by varying the content of MM. The ribbons contain minor phases besides the main phase of Re2Fe14B. X-ray techniques show that the diffraction peak intensities of the minor phase Fe3B vary with the content of constituent elements, indicating that the amount of minor phase could be tunable. The squareness of hysteresis loop is the best in MM13Fe80.5B6.5 ribbons, which should mainly ascribe to the less amount of minor phase. Henkel plots verify the more uniform magnetization reversals in MM13Fe80.5B6.5 ribbons, and the energy product achieves to the maximum of 12.74 MGOe with the coercivity of 6.50 kOe. With the increase of MM content the coercivity increases monotonically, and reaches to 9.13 kOe in MM15Fe77.5B7.5 ribbons, which should be related with the nature of the defects in the main phase. These investigations show that optimizing the content of constituent elements and phase constitution could improve magnetic properties in the resource-saving magnets of MM-Fe-B ribbons.
He, Peixin; Wang, Ke; Cai, Yingli; Hu, Xiaolong; Zheng, Yan; Zhang, Junjie; Liu, Wei
2018-06-01
Sclerotial formation is a key phase of the morel life cycle and lipids have been recorded as the main cytoplasmic reserves in sclerotia of Morchella fungi without any experimental verification. In this study, the ultrastructural features of the undifferentiated mycelia stage (MS) and three main sclerotial differentiation states (sclerotial initial [SI], sclerotial development [SD] and sclerotial maturation [SM]) were compared by transmission electron microscopy. The nature of the energy-rich substance in hypha and sclerotium of Morchella importuna was qualitatively investigated by confocal laser scanning microscopy and quantitatively studied by extraction of lipids. Sclerotia were observed to form from the repeated branching and enlargement of either terminal hyphae or subordinate hyphal branches, indicating a complex type of sclerotial development. Autophagy and apoptosis were involved in the sclerotial metamorphosis of the cultivated strain of M. importuna. During the SI phase, the characteristic features of autophagy (vacuolation, coalescence of small vacuoles, existence of autophagosomes and engulfment of autophagosomes by vacuoles) were observed. At the SD phase, apoptotic characteristics (condensation of the cytoplasm and nucleus, shrinkage of plasma membrane, extensive plasma membrane blebbing and existence of phagosomes) could be seen in some developing sclerotial cells. In the final stage of sclerotial morphogensis, the sclerotial cells showed a necrotic mode of cell death. In addition, confocal laser imaging studies of live cells indicated that the energy-rich substance in morel hyphae and sclerotia was lipid. The lipid content in sclerotia was significantly more than that in hyphal cells. To the best of our knowledge, this is the first detailed ultrastructural description highlighting the involvement of autophagy and apoptosis in sclerotial metamorphosis of Morchella species and lipid accumulation during morel sclerotial development was also first experimentally verified. This work will promote a better understanding of the mechanism of morel sclerotial metamorphosis. Copyright © 2018 Elsevier Ltd. All rights reserved.
Guang, Yang; Ge, Song; Han, Liu
2016-01-01
The harmonious development in society, economy and environment are crucial to regional sustained boom. However, the society, economy and environment are not respectively independent, but both mutually promotes one which, or restrict mutually complex to have the long-enduring overall process. The present study is an attempt to investigate the relationship and interaction of society, economy and environment in China based on the data from 2004 to 2013. The principal component analysis (PCA) model was employed to identify the main factors effecting the society, economy and environment subsystems, and SD (system dynamics) method used to carry out dynamic assessment for future state of sustainability from society, economy and environment perspective with future indicator values. Sustainable development in China was divided in the study into three phase from 2004 to 2013 based competitive values of these three subsystems. According to the results of PCA model, China is in third phase, and the economy growth is faster than the environment development, while the social development still maintained a steady and rapid growth, implying that the next step for sustainable development in China should focus on society development, especially the environment development.
Phase Transformation and Aging Behavior of Al0.5CoCrFeNiSi0.2 High-Entropy Alloy
NASA Astrophysics Data System (ADS)
Zhang, C.; Wu, G. F.; Dai, P. Q.
2015-05-01
An Al0.5CoCrFeNiSi0.2 high-entropy alloy was prepared by vacuum arc melting. The alloy was aged from 700 to 1100 °C. The effects of aging on the phase transformation and mechanical performances were explored. The as-cast alloy showed a dendritic (DR) microstructure. The DR region was an Fe,Cr-rich FCC phase, while the interdendritic (ID) region was a spinodal structure composed of Fe,Cr-rich BCC (A2) and Ni,Al-rich BCC (B2) phases. At aging temperatures between 700 and 900 °C, the Fe,Cr-rich BCC (A2) phase in the ID region transformed into σ and Fe,Cr-rich FCC phases. Meanwhile, some Ni,Al-rich FCC phase particles precipitated from the DR region. During aging at 1100 °C, the DR microstructure disappeared, and a microstructure composed of Fe,Cr-rich FCC and Ni,Al-rich BCC (B2) phases both possessing a lamellar shape was developed. The alloy exhibited evident hardening and lower tensile strain when the aging temperature was lower than 1000 °C, which was mainly attributed to the generation of the σ phase in the ID region. However, a contrasting behavior was observed when the aging temperature was higher than 1000 °C, which was attributed to the redissolution of the σ phase and the microstructure coarsening.
Aziz, Muhammad Tahir; Rehman, Tofeeq Ur; Qureshi, Sadia; Andleeb, Sidrah
2017-12-01
Background The aim of drug therapy is to attain distinct therapeutic effects that not only improve patient's quality of life but also reduce the inherent risks associated with the therapeutic use of drugs. Pharmacists play a key role in reducing these risks by developing appropriate interventions. Whether to accept or reject the intervention made by the pharmacist is a relevant consultant's decision. Objective To evaluate the impact of electronic prompts and follow-up of rejected pharmacy interventions by clinical pharmacists in an in-patient setting. Setting Shaukat Khanum Cancer Hospital & Research Center, Lahore, Pakistan. Method The study was conducted in two phases. Data for 3 months were collected for each phase of the study. Systematic and quantifiable consensus validity was developed for rejected interventions in phase 1, based on patient outcome analyses. Severity rating was assigned to assess the significance of interventions. Electronic prompts for follow-on interventions in phase 2 were then developed and implemented, including daily review via a multidisciplinary team (MDT) approach. Main outcome measure Validity of rejected interventions, acceptance of follow-on interventions before and after re-engineering the pharmacy processes, rejection rate and severity rating of follow-on interventions. Result Of a total of 2649 and 3064 interventions that were implemented during phase 1 and phase 2, 238 (9%) and 307 (10%) were rejected, respectively. Additionally, 133 (56%) were inappropriate rejections during phase 1. The estimated reliability between pharmacists regarding rejected interventions was 0.74 (95% CI of 0.69, 0.79, p 0.000). Prospective data were analysed after implementing electronic alerts and an MDT approach. The acceptance rate of follow-on interventions in phase 2 was 60% (184). Conclusion Electronic prompts for follow-on interventions together with an MDT approach enhance the optimization of pharmacotherapy, increase drug rationality and improve patient care.
Verification System: First System-Wide Performance Test
NASA Astrophysics Data System (ADS)
Chernobay, I.; Zerbo, L.
2006-05-01
System-wide performance tests are essential for the development, testing and evaluation of individual components of the verification system. In addition to evaluating global readiness it helps establishing the practical and financial requirements for eventual operations. The first system-wide performance test (SPT1) was conducted in three phases: - A preparatory phase in May-June 2004 - A performance testing phase in April-June 2005 - An evaluation phase in the last half of 2005. The preparatory phase was developmental in nature. The main objectives for the performance testing phase included establishment of performance baseline under current provisional mode of operation (CTBT/PC- 19/1/Annex II, CTBT/WGB-21/1), examination of established requirements and procedures for operation and maintenance. To establish a system-wide performance baseline the system configuration was fixed for April-May 2005. The third month (June 2005) was used for implementation of 21 test case scenarios to examine either particular operational procedures or the response of the system components to the failures simulated under controlled conditions. A total of 163 stations and 5 certified radionuclide laboratories of International Monitoring System (IMS) participated in the performance testing phase - about 50% of the eventual IMS network. 156 IMS facilities and 40 National Data Centres (NDCs) were connected to the International Data Centre (IDC) via Global Communication Infrastructure (GCI) communication links. In addition, 12 legacy stations in the auxiliary seismic network sent data to the IDC over the Internet. During the performance testing phase, the IDC produced all required products, analysed more than 6100 seismic events and 1700 radionuclide spectra. Performance of all system elements was documented and analysed. IDC products were compared with results of data processing at the NDCs. On the basis of statistics and information collected during the SPT1 a system-wide performance baseline under current guidelines for provisional Operation and Maintenance was established. The test provided feedback for further development of the draft IMS and IDC Operational Manuals and identified priority areas for further system development.
Local profile dependence of coercivity in (MM0.3Nd0.7)-Fe-B sintered magnets
NASA Astrophysics Data System (ADS)
Yu, Xiaoqiang; Zhu, Minggang; Liu, Weiqiang; Li, Wei; Sun, Yachao; Shi, Xiaoning; Yue, Ming
2018-03-01
Two magnets with the same nominal composition of (MM0.3Nd0.7)-Fe-B (Marked as A) and [(La0.27Ce0.53Pr0.03Nd0.17)0.3Nd0.7]-Fe-B (Marked as B) were prepared using traditional powder metallurgical process, respectively. In order to point out the difference between two magnets, the magnetic properties, microstructure and magnetic domain of both magnets were investigated. Both magnets have the same elements, but different raw materials of misch-metal (MM) and La/Ce/Pr/Nd pure metal, which induces different magnetic properties. The magnet A with Br of 13.1 kGs, Hcj of 7.6 kOe, (BH)max of 37.8 MGOe and magnet B with Br of 13.4 kGs, Hcj of 5.8 kOe, (BH)max of 34.5 MGOe are obtained. Although both magnets have the similar Br, magnet A has higher coercivity than that of magnet B. According to refined results of characteristic X-ray diffraction peaks, there is a hard magnetic main phase with higher magnetic anisotropy field (HA) in magnet A and opposite case happens on magnet B. SEM images demonstrate that magnet A has more continuous RE-rich phase and smaller grain size compared to that of magnet B, which contributes to enhancing the coercivity. In addition, two main phases of [Nd0.82(La, Ce)0.18]-Fe-B and [Nd0.75(La, Ce)0.25]-Fe-B were detected by the EDX calculation, and the two main phases in both magnets were observed by magnetic domains again. Compared to magnet B, 2:14:1 main phases in magnet A contain more [Nd0.82(La, Ce)0.18]-Fe-B main phases and less [Nd0.75(La, Ce)0.25]-Fe-B main phases, which also leads to higher coercivity due to the different HA among Nd2Fe14B, La2Fe14B and Ce2Fe14B phases. Therefore, it is concluded that MM substitution could exhibit better magnetic properties than (La0.27Ce0.53Pr0.03Nd0.17)-metal substitution. Furthermore, applications of MM are beneficial to fabricate (MM, Nd)-Fe-B permanent magnets with lower cost.
Development of an HPV Educational Protocol for Adolescents
Wetzel, Caitlin; Tissot, Abbigail; Kollar, Linda M.; Hillard, Paula A.; Stone, Rachel; Kahn, Jessica A.
2007-01-01
Study Objectives To develop an educational protocol about HPV and Pap tests for adolescents, to evaluate the protocol for understandability and clarity, and to evaluate the protocol for its effectiveness in increasing knowledge about HPV. Design In phase 1, investigators and adolescents developed the protocol. In phase 2, adolescents evaluated the protocol qualitatively, investigators evaluated its effectiveness in increasing HPV knowledge in a sample of adolescents, and the protocol was revised. In phase 3, investigators evaluated the effectiveness of the revised protocol in an additional adolescent sample. Setting Urban, hospital-based teen health center. Participants A total of 252 adolescent girls and boys in the three study phases. Main Outcome Measures Pre- and post-protocol knowledge about HPV, measured using a 10- or 11-item scale. Results Scores on the HPV knowledge scale increased significantly (p<.0001) among adolescents who participated in phases 2 and 3 after they received the protocol. Initial differences in scores based on race, insurance type and condom use were not noted post-protocol. Conclusion The protocol significantly increased knowledge scores about HPV in this population, regardless of sociodemographic characteristics and risk behaviors. Effective, developmentally appropriate educational protocols about HPV and Pap tests are particularly important in clinical settings as cervical cancer screening guidelines evolve, HPV DNA testing is integrated into screening protocols, and HPV vaccines become available. In-depth, one-on-one education about HPV may also prevent adverse psychosocial responses and promote healthy sexual and Pap screening behaviors in adolescents with abnormal HPV or Pap test results. Synopsis The investigators developed an educational protocol about HPV and Pap tests and evaluated its effectiveness in increasing knowledge about HPV among adolescents. PMID:17868894
Symmetric Topological Phases and Tensor Network States
NASA Astrophysics Data System (ADS)
Jiang, Shenghan
Classification and simulation of quantum phases are one of main themes in condensed matter physics. Quantum phases can be distinguished by their symmetrical and topological properties. The interplay between symmetry and topology in condensed matter physics often leads to exotic quantum phases and rich phase diagrams. Famous examples include quantum Hall phases, spin liquids and topological insulators. In this thesis, I present our works toward a more systematically understanding of symmetric topological quantum phases in bosonic systems. In the absence of global symmetries, gapped quantum phases are characterized by topological orders. Topological orders in 2+1D are well studied, while a systematically understanding of topological orders in 3+1D is still lacking. By studying a family of exact solvable models, we find at least some topological orders in 3+1D can be distinguished by braiding phases of loop excitations. In the presence of both global symmetries and topological orders, the interplay between them leads to new phases termed as symmetry enriched topological (SET) phases. We develop a framework to classify a large class of SET phases using tensor networks. For each tensor class, we can write down generic variational wavefunctions. We apply our method to study gapped spin liquids on the kagome lattice, which can be viewed as SET phases of on-site symmetries as well as lattice symmetries. In the absence of topological order, symmetry could protect different topological phases, which are often referred to as symmetry protected topological (SPT) phases. We present systematic constructions of tensor network wavefunctions for bosonic symmetry protected topological (SPT) phases respecting both onsite and spatial symmetries.
Novel antibiotics: are we still in the pre-post-antibiotic era?
Draenert, R; Seybold, U; Grützner, E; Bogner, J R
2015-04-01
Therapeutic efficacy and safety in infections due to multidrug-resistant bacteria can be improved by the clinical development of new compounds and devising new derivatives of already useful antibiotics. Due to a striking global increase in multidrug-resistant Gram-positive but even more Gram-negative organisms, new antibiotics are urgently needed. This paper provides a review of novel antibiotic compounds which are already in clinical development, mainly in phase III clinical trials. Each of these new trials increases the possibility of new antibiotics receiving approval.
Gilles, Martine Annie; Guélin, Jean-Charles; Desbrosses, Kévin; Wild, Pascal
2017-10-01
The working population is getting older. Workers must adapt to changing conditions to respond to the efforts required by the tasks they have to perform. In this laboratory-based study, we investigated the capacities of motor adaptation as a function of age and work pace. Two phases were identified in the task performed: a collection phase, involving dominant use of the lower limbs; and an assembly phase, involving bi-manual motor skills. Results showed that senior workers were mainly limited during the collection phase, whereas they had less difficulty completing the assembly phase. However, senior workers did increase the vertical force applied while assembling parts, whatever the work pace. In younger and middle-aged subjects, vertical force was increased only for the faster pace. Older workers could adapt to perform repetitive tasks under different time constraints, but adaptation required greater effort than for younger workers. These results point towards a higher risk of developing musculoskeletal disorders among seniors. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Xu, Yangzi; Lu, Yuan; Sundberg, Kristin L.; Liang, Jianyu; Sisson, Richard D.
2017-05-01
An experimental investigation on the effects of post-annealing treatments on the microstructure, mechanical properties and corrosion behavior of direct metal laser sintered Ti-6Al-4V alloys has been conducted. The microstructure and phase evolution as affected by annealing treatment temperature were examined through scanning electron microscopy and x-ray diffraction. The tensile properties and Vickers hardness were measured and compared to the commercial Grade 5 Ti-6Al-4V alloy. Corrosion behavior of the parts was analyzed electrochemically in simulated body fluid at 37 °C. It was found out that the as-printed parts mainly composed of non-equilibrium α' phase. Annealing treatment allowed the transformation from α' to α phase and the development of β phase. The tensile test results indicated that post-annealing treatment could improve the ductility and decrease the strength. The as-printed Ti-6Al-4V part exhibits inferior corrosion resistance compared to the commercial alloy, and post-annealing treatment can reduce its susceptibility to corrosion by reducing the two-phase interface area.
Tang, Bing; Yu, Guojun; Fang, Jianzhang; Shi, Taihong
2010-05-15
An emulsion liquid membrane (ELM)-crystallization process, using hypophosphorous acid as a reducing agent in the internal aqueous phase, has been developed for the purpose of recovering high-purity silver directly from dilute industrial effluents (waste rinse water). After pretreatment with HNO(3), silver in waste rinse water can be reliably recovered with high efficiency through the established process. The main parameters in the process of ELM-crystallization include the concentration of carrier in the membrane phase, the concentration of reducing agent in the internal aqueous phase, and the treatment ratio, which influence the recovery efficiency to various extents and must be controlled carefully. The results indicated that more than 99.5% (wt.) of the silver ions in the external aqueous phase were extracted by the ELM-crystallization process, with an average efficiency of recovery of 99.24% (wt.) and a purity of 99.92% (wt.). The membrane phase can be used repeatedly without loss of the efficiency of recovery. Copyright (c) 2009 Elsevier B.V. All rights reserved.
Mazzeo Rinaldi, Francesco
2016-06-01
In the last two decades, EU policies have had a fundamental role in orienting regional/local development. The objective of this work is set in this context as it intends to analyze the local development programs activated in Sicily in the last three programming periods. The main aim is to explore whether the EU partnership principle influenced cooperation among local actors, assessing the continuity of local institutional coalition in managing different local development programs within the regional development policy system. We focus, in particular, on Strategic Plans (SP) promoted in Sicily in the transition phase between the 2000-2006 and the 2007-2013 periods. Copyright © 2016 Elsevier Ltd. All rights reserved.
Giannuzzi, Viviana; Landi, Annalisa; Bosone, Enrico; Giannuzzi, Floriana; Nicotri, Stefano; Torrent-Farnell, Josep; Bonifazi, Fedele; Felisi, Mariagrazia; Bonifazi, Donato; Ceci, Adriana
2017-09-11
The research and development process in the field of rare diseases is characterised by many well-known difficulties, and a large percentage of orphan medicinal products do not reach the marketing approval.This work aims at identifying orphan medicinal products that failed the developmental process and investigating reasons for and possible factors influencing failures. Drugs designated in Europe under Regulation (European Commission) 141/2000 in the period 2000-2012 were investigated in terms of the following failures: (1) marketing authorisation failures (refused or withdrawn) and (2) drugs abandoned by sponsors during development.Possible risk factors for failure were analysed using statistically validated methods. This study points out that 437 out of 788 designations are still under development, while 219 failed the developmental process. Among the latter, 34 failed the marketing authorisation process and 185 were abandoned during the developmental process. In the first group of drugs (marketing authorisation failures), 50% reached phase II, 47% reached phase III and 3% reached phase I, while in the second group (abandoned drugs), the majority of orphan medicinal products apparently never started the development process, since no data on 48.1% of them were published and the 3.2% did not progress beyond the non-clinical stage.The reasons for failures of marketing authorisation were: efficacy/safety issues (26), insufficient data (12), quality issues (7), regulatory issues on trials (4) and commercial reasons (1). The main causes for abandoned drugs were efficacy/safety issues (reported in 54 cases), inactive companies (25.4%), change of company strategy (8.1%) and drug competition (10.8%). No information concerning reasons for failure was available for 23.2% of the analysed products. This analysis shows that failures occurred in 27.8% of all designations granted in Europe, the main reasons being safety and efficacy issues. Moreover, the stage of development reached by drugs represents a specific risk factor for failures. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
A Novel Multi-Class Ensemble Model for Classifying Imbalanced Biomedical Datasets
NASA Astrophysics Data System (ADS)
Bikku, Thulasi; Sambasiva Rao, N., Dr; Rao, Akepogu Ananda, Dr
2017-08-01
This paper mainly focuseson developing aHadoop based framework for feature selection and classification models to classify high dimensionality data in heterogeneous biomedical databases. Wide research has been performing in the fields of Machine learning, Big data and Data mining for identifying patterns. The main challenge is extracting useful features generated from diverse biological systems. The proposed model can be used for predicting diseases in various applications and identifying the features relevant to particular diseases. There is an exponential growth of biomedical repositories such as PubMed and Medline, an accurate predictive model is essential for knowledge discovery in Hadoop environment. Extracting key features from unstructured documents often lead to uncertain results due to outliers and missing values. In this paper, we proposed a two phase map-reduce framework with text preprocessor and classification model. In the first phase, mapper based preprocessing method was designed to eliminate irrelevant features, missing values and outliers from the biomedical data. In the second phase, a Map-Reduce based multi-class ensemble decision tree model was designed and implemented in the preprocessed mapper data to improve the true positive rate and computational time. The experimental results on the complex biomedical datasets show that the performance of our proposed Hadoop based multi-class ensemble model significantly outperforms state-of-the-art baselines.
Rapid Loss of Radiation Belt Relativistic Electrons by EMIC Waves
DOE Office of Scientific and Technical Information (OSTI.GOV)
Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan
How relativistic electrons are lost is an important question surrounding the complex dynamics of the Earth's outer radiation belt. Radial loss to the magnetopause and local loss to the atmosphere are two main competing paradigms. Here on the basis of the analysis of a radiation belt storm event on 27 February 2014, we present new evidence for the electromagnetic ion cyclotron (EMIC) wave-driven local precipitation loss of relativistic electrons in the heart of the outer radiation belt. During the main phase of this storm, the radial profile of relativistic electron phase space density was quasi-monotonic, qualitatively inconsistent with the predictionmore » of radial loss theory. The local loss at low L shells was required to prevent the development of phase space density peak resulting from the radial loss process at high L shells. The rapid loss of relativistic electrons in the heart of outer radiation belt was observed as a dip structure of the electron flux temporal profile closely related to intense EMIC waves. Our simulations further confirm that the observed EMIC waves within a quite limited longitudinal region were able to reduce the off-equatorially mirroring relativistic electron fluxes by up to 2 orders of magnitude within about 1.5 h.« less
Phase constitution in the interfacial region of laser penetration brazed magnesium–steel joints
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miao, Yugang; Han, Duanfeng, E-mail: handuanfeng@gmail.com; Xu, Xiangfang
2014-07-01
The phase constitution in the interfacial region of laser penetration brazed magnesium–steel joints was investigated using electron microscopy. From the distribution of elements, the transition zone was mainly composed of elements Mg and Fe along with some Al and O. Furthermore, the transition layer consisted mainly of intermetallic compounds and metal oxides. The compounds were identified as Al-rich phases, such as Mg{sub 17}Al{sub 12}, Mg{sub 2}Al{sub 3}, FeAl and Fe{sub 4}Al{sub 13}. More noteworthy was that the thickness of the transition layer was determined by Fe–Al compounds. The presence of FeAl and Fe{sub 4}Al{sub 13} was a result of themore » complex processes that were associated with the interfacial reaction of solid steel and liquid Mg–Al alloy. - Highlights: • A technology of laser penetration brazed Mg alloy and steel has been developed. • The interface of Mg/Fe dissimilar joints was investigated using electron microscopy. • The transition layer consisted of intermetallic compounds and metal oxides. • Moreover, the thickness of transition layer was determined by Fe/Al compounds. • The presence of FeAl and Fe{sub 4}Al{sub 13} was associated with the interfacial reaction.« less
Rapid Loss of Radiation Belt Relativistic Electrons by EMIC Waves
Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; ...
2017-08-31
How relativistic electrons are lost is an important question surrounding the complex dynamics of the Earth's outer radiation belt. Radial loss to the magnetopause and local loss to the atmosphere are two main competing paradigms. Here on the basis of the analysis of a radiation belt storm event on 27 February 2014, we present new evidence for the electromagnetic ion cyclotron (EMIC) wave-driven local precipitation loss of relativistic electrons in the heart of the outer radiation belt. During the main phase of this storm, the radial profile of relativistic electron phase space density was quasi-monotonic, qualitatively inconsistent with the predictionmore » of radial loss theory. The local loss at low L shells was required to prevent the development of phase space density peak resulting from the radial loss process at high L shells. The rapid loss of relativistic electrons in the heart of outer radiation belt was observed as a dip structure of the electron flux temporal profile closely related to intense EMIC waves. Our simulations further confirm that the observed EMIC waves within a quite limited longitudinal region were able to reduce the off-equatorially mirroring relativistic electron fluxes by up to 2 orders of magnitude within about 1.5 h.« less
Hybrid simulations of Alfvén modes driven by energetic particles
NASA Astrophysics Data System (ADS)
Zhu, J.; Ma, Z. W.; Wang, S.
2016-12-01
A hybrid kinetic-magnetohydrodynamic code (CLT-K) is developed to study nonlinear dynamics of Alfvén modes driven by energetic particles (EP). A n = 2 toroidicity-induced discrete shear Alfvén eigenmode (TAE)-type energetic particle mode (EPM) with two dominant poloidal harmonics (m = 2 and 3) is first excited and its frequency remains unchanged in the early phase. Later, a new branch of the n = 2 frequency with a single dominant poloidal mode (m = 3) splits from the original TAE-type EPM. The new single m EPM (m = 3) slowly moves radially outward with the downward chirping of the frequency and the mode amplitude remains at a higher level. The original EPM remains at its original position without the frequency chirping, but its amplitude decays with time. Finally, the m = 3 EPM becomes dominant and the frequency falls into the β-induced gap of the Alfvén continuum. The redistribution of the δf in the phase space is consistent with the mode frequency downward chirping and the drifting direction of the resonance region is mainly due to the biased free energy profile. The transition from a TAE-type EPM to a single m EPM is mainly caused by extension of the p = 0 trapped particle resonance in the phase space.
OVERVIEW OF ENHANCED HANFORD SINGLE-SHELL TANK (SST) INTEGRITY PROJECT - 12128
DOE Office of Scientific and Technical Information (OSTI.GOV)
VENETZ TJ; BOOMER KD; WASHENFELDER DJ
2012-01-25
To improve the understanding of the single-shell tanks integrity, Washington River Protection Solutions, LLC, the USDOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank (SST) Integrity Project in 2009. An expert panel on SST integrity, consisting of various subject matters experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration, Seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for the Hanford Federalmore » Agreement and Compliance Order, which is also known as the Tri-Party Agreement. The change package identified two phases of work for SST integrity. The initial phase has been focused on efforts to envelope the integrity of the tanks. The initial phase was divided into two primary areas of investigation: structural integrity and leak integrity. If necessary based on the outcome from the initial work, a second phase would be focused on further definition of the integrity of the concrete and liners. Combined these two phases are designed to support the formal integrity assessment of the Hanford SSTs in 2018 by Independent Qualified Registered Engineer. The work to further define the DOE's understanding of the structural integrity SSTs involves preparing a modern Analysis of Record using a finite element analysis program. Structural analyses of the SSTs have been conducted since 1957, but these analyses used analog calculation, less rigorous models, or focused on individual structures. As such, an integrated understanding of all of the SSTs has not been developed to modern expectations. In support of this effort, other milestones will address the visual inspection of the tank concrete and the collection of concrete core samples from the tanks for analysis of current mechanics properties. The work on the liner leak integrity has examined the leaks from 23 tanks with liner failures. Individual leak assessments are being developed for each tank to identify the leak cause and location. Also a common cause study is being performed to take the data from individual tanks to look for trends in the failure. Supporting this work is an assessment of the leak rate from tanks at both Hanford and the Savannah River Site and a new method to locate leak sites in tank liner using ionic conductivity. A separate activity is being conducted to examine the propensity for corrosion in select single shell tanks with aggressive waste layers. The work for these two main efforts will provide the basis for the phase two planning. If the margins identified aren't sufficient to ensure the integrity through the life of the mission, phase two would focus on activities to further enhance the understanding of tank integrity. Also coincident with any phase-two work would be the integrity analysis for the tanks, which would be complete in 2018. With delays in the completion of waste treatment facilities at Hanford, greater reliance on safe, continued storage of waste in the single shell tanks is increased in importance. The goal of integrity assessment would provide basis to continue SST activities till the end of the treatment mission.« less
Development of MQXF: The Nb 3Sn low-β quadrupole for the HiLumi LHC
Ferracin, P.; G. Ambrosio; Anerella, M.; ...
2015-12-18
The High Luminosity (HiLumi) Large Hadron Collider (LHC) project has, as the main objective, to increase the LHC peak luminosity by a factor five and the integrated luminosity by a factor ten. This goal will be achieved mainly with a new interaction region layout, which will allow a stronger focusing of the colliding beams. The target will be to reduce the beam size in the interaction points by a factor of two, which requires doubling the aperture of the low-β (or inner triplet) quadrupole magnets. The use of Nb3Sn superconducting material and, as a result, the possibility of operating atmore » magnetic field levels in the windings higher than 11 T will limit the increase in length of these quadrupoles, called MQXF, to acceptable levels. After the initial design phase, where the key parameters were chosen and the magnet's conceptual design finalized, the MQXF project, a joint effort between the U.S. LHC Accelerator Research Program and the Conseil Europeen pour la Recherche Nucleaire (CERN), has now entered the construction and test phase of the short models. Concurrently, the preparation for the development of the full-length prototypes has been initiated. Lastly, this paper will provide an overview of the project status, describing and reporting on the performance of the superconducting material, the lessons learnt during the fabrication of superconducting coils and support structure, and the fine tuning of the magnet design in view of the start of the prototyping phase.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malhotra, V.M.; Wright, M.A.
1995-12-31
The main goal of this project is to develop a bench-scale procedure to design and fabricate advanced brake and structural composite materials from Illinois coal combustion residues. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), differential thermal analysis (DTA), and transmission-Fourier transform infrared (FTIR) were conducted on PCC fly ash (Baldwin), FBC fly ash (ADM unit1-6), FBC fly ash (S.I. coal), FBC spent bed ash (ADM unit1-6), bottom ash, and scrubber sludge (CWLP) residues to characterize their geometrical shapes, mineral phases, and thermal stability. Our spectroscopic results indicate that the scrubber sludge is mainly composed of a gypsum-like phase whosemore » lattice structure is different from the lattice structure of conventional gypsum, and sludge does not contain hannebachite (CaSO{sub 3}0.5H{sub 2}O) phase. In the second and third quarters the focus of research has been on developing protocols for the formation of advanced brake composites and structural composites. Our attempts to fabricate brake frictional shoes, in the form of 1.25 inch disks, from PCC fly ash, FBC spent bed ash, scrubber sludge, coal char, iron particles, and coal tar were successful. Based on the experience gained and microscopic analyses, we have now upscaled our procedures to fabricate 2.5 inch diameter disks from coal combustion residues. The SEM and Young`s modulus analyses of brake composites fabricated at 400 psi < Pressure < 2200 psi suggest pressure has a strong influence on the particle packing and the filling of interstices in our composites.« less
The cell-cycle interactome: a source of growth regulators?
Blomme, Jonas; Inzé, Dirk; Gonzalez, Nathalie
2014-06-01
When plants develop, cell proliferation and cell expansion are tightly controlled in order to generate organs with a determinate final size such as leaves. Several studies have demonstrated the importance of the cell proliferation phase for leaf growth, illustrating that cell-cycle regulation is crucial for correct leaf development. A large and complex set of interacting proteins that constitute the cell-cycle interactome controls the transition from one cell-cycle phase to another. Here, we review the current knowledge on cell-cycle regulators from this interactome affecting final leaf size when their expression is altered, mainly in Arabidopsis. In addition to the description of mutants of CYCLIN-DEPENDENT KINASES (CDKs), CYCLINS (CYCs), and their transcriptional and post-translational regulators, a phenotypic analysis of gain- and loss-of-function mutants for 27 genes encoding proteins that interact with cell-cycle proteins is presented. This compilation of information shows that when cell-cycle-related genes are mis-expressed, leaf growth is often altered and that, seemingly, three main trends appear to be crucial in the regulation of final organ size by cell-cycle-related genes: (i) cellular compensation; (ii) gene dosage; and (iii) correct transition through the G2/M phase by ANAPHASE PROMOTING COMPLEX/CYCLOSOME (APC/C) activation. In conclusion, this meta-analysis shows that the cell-cycle interactome is enriched in leaf growth regulators, and illustrates the potential to identify new leaf growth regulators among putative new cell-cycle regulators. © The Author 2013. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Final waste forms project: Performance criteria for phase I treatability studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gilliam, T.M.; Hutchins, D.A.; Chodak, P. III
1994-06-01
This document defines the product performance criteria to be used in Phase I of the Final Waste Forms Project. In Phase I, treatability studies will be performed to provide {open_quotes}proof-of-principle{close_quotes} data to establish the viability of stabilization/solidification (S/S) technologies. This information is required by March 1995. In Phase II, further treatability studies, some at the pilot scale, will be performed to provide sufficient data to allow treatment alternatives identified in Phase I to be more fully developed and evaluated, as well as to reduce performance uncertainties for those methods chosen to treat a specific waste. Three main factors influence themore » development and selection of an optimum waste form formulation and hence affect selection of performance criteria. These factors are regulatory, process-specific, and site-specific waste form standards or requirements. Clearly, the optimum waste form formulation will require consideration of performance criteria constraints from each of the three categories. Phase I will focus only on the regulatory criteria. These criteria may be considered the minimum criteria for an acceptable waste form. In other words, a S/S technology is considered viable only if it meet applicable regulatory criteria. The criteria to be utilized in the Phase I treatability studies were primarily taken from Environmental Protection Agency regulations addressed in 40 CFR 260 through 265 and 268; and Nuclear Regulatory Commission regulations addressed in 10 CFR 61. Thus the majority of the identified criteria are independent of waste form matrix composition (i.e., applicable to cement, glass, organic binders etc.).« less
Hasan, Mehedi; Guemri, Rabiaa; Maldonado-Basilio, Ramón; Lucarz, Frédéric; de Bougrenet de la Tocnaye, Jean-Louis; Hall, Trevor
2014-12-15
A photonic circuit design for implementing frequency 8-tupling and 24-tupling is proposed. The front- and back-end of the circuit comprises 4×4 MMI couplers enclosing an array of four pairs of phase modulators and 2×2 MMI couplers. The proposed design for frequency multiplication requires no optical or electrical filters, the operation is not limited to carefully adjusted modulation indexes, and the drift originated from static DC bias is mitigated by making use of the intrinsic phase relations of multi-mode interference couplers. A transfer matrix approach is used to represent the main building blocks of the design and hence to describe the operation of the frequency 8-tupling and 24-tupling. The concept is theoretically developed and demonstrated by simulations. Ideal and imperfect power imbalances in the multi-mode interference couplers, as well as ideal and imperfect phases of the electric drives to the phase modulators, are analyzed.
Numerical Simulation and Chaotic Analysis of an Aluminum Holding Furnace
NASA Astrophysics Data System (ADS)
Wang, Ji-min; Zhou, Yuan-yuan; Lan, Shen; Chen, Tao; Li, Jie; Yan, Hong-jie; Zhou, Jie-min; Tian, Rui-jiao; Tu, Yan-wu; Li, Wen-ke
2014-12-01
To achieve high heat efficiency, low pollutant emission and homogeneous melt temperature during thermal process of secondary aluminum, taking into account the features of aluminum alloying process, a CFD process model was developed and integrated with heat load and aluminum temperature control model. This paper presented numerical simulation of aluminum holding furnaces using the customized code based on FLUENT packages. Thermal behaviors of aluminum holding furnaces were investigated by probing into main physical fields such as flue gas temperature, velocity, and concentration, and combustion instability of aluminum holding process was represented by chaos theory. The results show that aluminum temperature uniform coefficient firstly decreases during heating phase, then increases and reduces alternately during holding phase, lastly rises during standing phase. Correlation dimension drops with fuel velocity. Maximal Lyapunov exponent reaches to a maximum when air-fuel ratio is close to 1. It would be a clear comprehension about each phase of aluminum holding furnaces to find new technology, retrofit furnace design, and optimize parameters combination.
Cophasing techniques for extremely large telescopes
NASA Astrophysics Data System (ADS)
Devaney, Nicholas; Schumacher, Achim
2004-07-01
The current designs of the majority of ELTs envisage that at least the primary mirror will be segmented. Phasing of the segments is therefore a major concern, and a lot of work is underway to determine the most suitable techniques. The techniques which have been developed are either wave optics generalizations of classical geometric optics tests (e.g. Shack-Hartmann and curvature sensing) or direct interferometric measurements. We present a review of the main techniques proposed for phasing and outline their relative merits. We consider problems which are specific to ELTs, e.g. vignetting of large parts of the primary mirror by the secondary mirror spiders, and the need to disentangle phase errors arising in different segmented mirrors. We present improvements in the Shack-Hartmann and curvature sensing techniques which allow greater precision and range. Finally, we describe a piston plate which simulates segment phasing errors and show the results of laboratory experiments carried out to verify the precision of the Shack-Hartmann technique.
A Concept Analysis of Holistic Care by Hybrid Model.
Jasemi, Madineh; Valizadeh, Leila; Zamanzadeh, Vahid; Keogh, Brian
2017-01-01
Even though holistic care has been widely discussed in the health care and professional nursing literature, there is no comprehensive definition of it. Therefore, the aim of this article is to present a concept analysis of holistic care which was developed using the hybrid model. The hybrid model comprises three phases. In the theoretical phase, characteristics of holistic care were identified through a review of the literature from CINAHL, MEDLINE, PubMed, OVID, and Google Scholar databases. During the fieldwork phase, in-depth interviews were conducted with eight nurses who were purposely selected. Finally, following an analysis of the literature and the qualitative interviews, a theoretical description of the concept of holistic care was extracted. Two main themes were extracted of analytical phase: "Holistic care for offering a comprehensive model for caring" and "holistic care for improving patients' and nurses' conditions." By undertaking a conceptual analysis of holistic care, its meaning can be clarified which will encourage nursing educators to include holistic care in nursing syllabi, and consequently facilitate its provision in practice.
Wang, Qian; Chen, Xiaoguang; Zhu, Lin; Yan, Jiuchun; Lai, Zhiwei; Zhao, Pizhi; Bao, Juncheng; Lv, Guicai; You, Chen; Zhou, Xiaoyu; Zhang, Jian; Li, Yuntao
2017-01-01
Al-50Si alloys were joined by rapid ultrasound-induced transient-liquid-phase bonding method using Zn foil as interlayer at 390°C in air, below the melt point of interlayer. The fracture of oxide films along the edge of Si particles led to contact and inter-diffusion between aluminum substrate and Zn interlayer, and liquefied Zn-Al alloys were developed. The width of Zn-Al alloys gradually decreased with increasing the ultrasonic vibration time due to liquid squeezing out and accelerated diffusion. A stage of isothermal solidification existed, and the completion time was significantly shortened. In the liquid metal, the acoustic streaming and ultrasonic cavitations were induced. As the process developed, much more Si particles, which were particulate-reinforced phases of Al-50Si, gradually migrated to the center of soldering seam. The highest average shear strength of joints reached to 94.2MPa, and the fracture mainly occurred at the base metal. Copyright © 2016 Elsevier B.V. All rights reserved.
Emerging lipid-lowering drugs: squalene synthase inhibitors.
Elsayed, Raghda K; Evans, Jeffery D
2008-06-01
Lapaquistat was the only squalene synthase inhibitor in Phase III clinical trials in Europe and the United States, but was recently discontinued from clinical development. Unlike statins, the inhibition of de novo cholesterol biosynthesis by lapaquistat does not deplete mevalonate, a precursor of isoprenoids. Isoprenoids are critical in cell growth and metabolism. The present review will focus on the chemistry, pharmacology, and lipid-lowering effects of novel squalene synthase inhibitors. A search of Pubmed, IPA, and GoogleScholar for studies (animal and human) and review articles published in English between 1990 and April 2008, using the search terms "squalene synthase inhibitors" or "lapaquistat". All clinical trials identified were then cross-referenced for their citations. All literature identified was then complied for this analysis. Lapaquistat mainly targets LDL-C, but may have some effect on HDL-C and TG. Preliminary reports on Phase II and Phase III associated lapaquistat 100 mg with elevated hepatic enzymes. Hepatotoxicity, possible drug-drug interaction with statins, and the investigation of a statin/coenzyme Q10 combination are among the few challenges that impeded lapaquistat's clinical development.
Enhancing the quality of argumentation in school science
NASA Astrophysics Data System (ADS)
Osborne, Jonathan; Erduran, Sibel; Simon, Shirley
2004-12-01
The research reported in this study focuses on the design and evaluation of learning environments that support the teaching and learning of argumentation in a scientific context. The research took place over 2 years, between 1999 and 2001, in junior high schools in the greater London area. The research was conducted in two phases. In phase 1, working with a group of 12 science teachers, the main emphasis was to develop sets of materials and strategies to support argumentation in the classroom, and to support and assess teachers' development with teaching argumentation. Data were collected by video- and audio-recording the teachers' attempts to implement these lessons at the beginning and end of the year. During this phase, analytical tools for evaluating the quality of argumentation were developed based on Toulmin's argument pattern. Analysis of the data shows that there was significant development in the majority of teachers use of argumentation across the year. Results indicate that the pattern of use of argumentation is teacher-specific, as is the nature of the change. In phase 2 of the project, the focus of this paper, teachers taught the experimental groups a minimum of nine lessons which involved socioscientific or scientific argumentation. In addition, these teachers taught similar lessons to a comparison group at the beginning and end of the year. The purpose of this research was to assess the progression in student capabilities with argumentation. For this purpose, data were collected from 33 lessons by video-taping two groups of four students in each class engaging in argumentation. Using a framework for evaluating the nature of the discourse and its quality developed from Toulmin's argument pattern, the findings show that there was improvement in the quality of students' argumentation. This research presents new methodological developments for work in this field.
Large liquid rocket engine transient performance simulation system
NASA Technical Reports Server (NTRS)
Mason, J. R.; Southwick, R. D.
1989-01-01
Phase 1 of the Rocket Engine Transient Simulation (ROCETS) program consists of seven technical tasks: architecture; system requirements; component and submodel requirements; submodel implementation; component implementation; submodel testing and verification; and subsystem testing and verification. These tasks were completed. Phase 2 of ROCETS consists of two technical tasks: Technology Test Bed Engine (TTBE) model data generation; and system testing verification. During this period specific coding of the system processors was begun and the engineering representations of Phase 1 were expanded to produce a simple model of the TTBE. As the code was completed, some minor modifications to the system architecture centering on the global variable common, GLOBVAR, were necessary to increase processor efficiency. The engineering modules completed during Phase 2 are listed: INJTOO - main injector; MCHBOO - main chamber; NOZLOO - nozzle thrust calculations; PBRNOO - preburner; PIPE02 - compressible flow without inertia; PUMPOO - polytropic pump; ROTROO - rotor torque balance/speed derivative; and TURBOO - turbine. Detailed documentation of these modules is in the Appendix. In addition to the engineering modules, several submodules were also completed. These submodules include combustion properties, component performance characteristics (maps), and specific utilities. Specific coding was begun on the system configuration processor. All functions necessary for multiple module operation were completed but the SOLVER implementation is still under development. This system, the Verification Checkout Facility (VCF) allows interactive comparison of module results to store data as well as provides an intermediate checkout of the processor code. After validation using the VCF, the engineering modules and submodules were used to build a simple TTBE.
Thermodynamics of concentrated solid solution alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gao, Michael C.; Zhang, C.; Gao, P.
This study reviews the three main approaches for predicting the formation of concentrated solid solution alloys (CSSA) and for modeling their thermodynamic properties, in particular, utilizing the methodologies of empirical thermo-physical parameters, CALPHAD method, and first-principles calculations combined with hybrid Monte Carlo/Molecular Dynamics (MC/MD) simulations. In order to speed up CSSA development, a variety of empirical parameters based on Hume-Rothery rules have been developed. Herein, these parameters have been systematically and critically evaluated for their efficiency in predicting solid solution formation. The phase stability of representative CSSA systems is then illustrated from the perspectives of phase diagrams and nucleation drivingmore » force plots of the σ phase using CALPHAD method. The temperature-dependent total entropies of the FCC, BCC, HCP, and σ phases in equimolar compositions of various systems are presented next, followed by the thermodynamic properties of mixing of the BCC phase in Al-containing and Ti-containing refractory metal systems. First-principles calculations on model FCC, BCC and HCP CSSA reveal the presence of both positive and negative vibrational entropies of mixing, while the calculated electronic entropies of mixing are negligible. Temperature dependent configurational entropy is determined from the atomic structures obtained from MC/MD simulations. Current status and challenges in using these methodologies as they pertain to thermodynamic property analysis and CSSA design are discussed.« less
Thermodynamics of concentrated solid solution alloys
Gao, Michael C.; Zhang, C.; Gao, P.; ...
2017-10-12
This study reviews the three main approaches for predicting the formation of concentrated solid solution alloys (CSSA) and for modeling their thermodynamic properties, in particular, utilizing the methodologies of empirical thermo-physical parameters, CALPHAD method, and first-principles calculations combined with hybrid Monte Carlo/Molecular Dynamics (MC/MD) simulations. In order to speed up CSSA development, a variety of empirical parameters based on Hume-Rothery rules have been developed. Herein, these parameters have been systematically and critically evaluated for their efficiency in predicting solid solution formation. The phase stability of representative CSSA systems is then illustrated from the perspectives of phase diagrams and nucleation drivingmore » force plots of the σ phase using CALPHAD method. The temperature-dependent total entropies of the FCC, BCC, HCP, and σ phases in equimolar compositions of various systems are presented next, followed by the thermodynamic properties of mixing of the BCC phase in Al-containing and Ti-containing refractory metal systems. First-principles calculations on model FCC, BCC and HCP CSSA reveal the presence of both positive and negative vibrational entropies of mixing, while the calculated electronic entropies of mixing are negligible. Temperature dependent configurational entropy is determined from the atomic structures obtained from MC/MD simulations. Current status and challenges in using these methodologies as they pertain to thermodynamic property analysis and CSSA design are discussed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
François, B.; Boudot, R.; Calosso, C. E.
2014-09-15
We report the development, absolute phase noise, and residual phase noise characterization of a 9.192 GHz microwave frequency synthesis chain devoted to be used as a local oscillator in a high-performance cesium vapor cell atomic clock based on coherent population trapping (CPT). It is based on frequency multiplication of an ultra-low phase noise 100 MHz oven-controlled quartz crystal oscillator using a nonlinear transmission line-based chain. Absolute phase noise performances of the 9.192 GHz output signal are measured to be −42, −100, −117 dB rad{sup 2}/Hz and −129 dB rad{sup 2}/Hz at 1 Hz, 100 Hz, 1 kHz, and 10 kHz offset frequencies, respectively. Comparedmore » to current results obtained in a state-of-the-art CPT-based frequency standard developed at LNE-SYRTE, this represents an improvement of 8 dB and 10 dB at f = 166 Hz and f = 10 kHz, respectively. With such performances, the expected Dick effect contribution to the atomic clock short term frequency stability is reported at a level of 6.2 × 10{sup −14} at 1 s integration time, that is a factor 3 higher than the atomic clock shot noise limit. Main limitations are pointed out.« less
Menković, N; Savikin-Fodulović, K; Savin, K
2000-03-01
The chemical investigation of MeOH extracts of Gentiana lutea leaves and flowers showed that xanthones were one of the dominant class of compounds. Secoiridoids and flavonoids were also recorded. The amount of secondary metabolites varied depending on development stage. In the phase of flowering, leaves are rich with compounds possessing C-glycoside structures while O-glycoside structures accumulate mainly before flowering.
Developing a global model of magnetospheric substorms
NASA Astrophysics Data System (ADS)
Kan, J. R.
1990-09-01
Competing models of magnetospheric substorms are discussed. The definitions of the three substorm phases are presented, and the advantages and drawbacks of the near-earth X-line model, magnetosphere-ionosphere coupling model, low-latitude boundary layer model, and thermal catastrophe model are examined. It is shown that the main challenge to achieving a quantitative understanding of the magnetospheric signatures of substorms is to understand the anomalous dissipation processes in collisionless plasmas.
NASA Technical Reports Server (NTRS)
Neal, Valerie; Shields, Nicholas, Jr.; Carr, Gerald P.; Pogue, William; Schmitt, Harrison H.; Schulze, Arthur E.
1988-01-01
The focus is on Extravehicular Activity (EVA) systems requirements definition for an advanced space mission: remote-from-main base EVA on the Moon. The lunar environment, biomedical considerations, appropriate hardware design criteria, hardware and interface requirements, and key technical issues for advanced lunar EVA were examined. Six remote EVA scenarios (three nominal operations and three contingency situations) were developed in considerable detail.
Asteroid 5535 Annefrank size, shape, and orientation: Stardust first results
NASA Technical Reports Server (NTRS)
Duxbury, T. C.; Newburn, R. L., Jr.; Acton, C. H.; Carranza, E.; McElrath, T. P.; Ryan, R. E.; Synnott, S. P.; You, T. H.; Brownlee, D. E.; Cheuvront, A. R.;
2004-01-01
The NASA Discovery Stardust spacecraft flew by the main belt asteroid 5535 Annefrank at a distance of 3100 km and a speed of 7.4 km/s in November 2002 to test the encounter sequence developed for its primary science target, the comet 81P/Wild2. During this testing, over 70 images of Annefrank were obtained, taken over a phase angle range from 40 to 140 degrees.
Diffusion bonding aeroengine components
NASA Astrophysics Data System (ADS)
Fitzpatrick, G. A.; Broughton, T.
1988-10-01
The use of diffusion bonding processes at Rolls-Royce for the manufacture of titanium-alloy aircraft engine components and structures is described. A liquid-phase diffusion bonding process called activated diffusion bonding has been developed for the manufacture of the hollow titanium wide chord fan blade. In addition, solid-state diffusion bonding is being used in the manufacture of hollow vane/blade airfoil constructions mainly in conjunction with superplastic forming and hot forming techniques.
The potential of SGLT2 inhibitors in phase II clinical development for treating type 2 diabetes.
Pafili, K; Maltezos, E; Papanas, N
2016-10-01
There is now an abundance of anti-diabetic agents. However, only few patients achieve glycemic targets. Moreover, current glucose-lowering agents mainly depend upon insulin secretion or function. Sodium glucose co-transporter type 2 (SGLT2) inhibitors present a novel glucose-lowering therapy, inducing glycosuria in an insulin-independent fashion. In this review, the authors discuss the key efficacy and safety data from phase II clinical trials in type 2 diabetes mellitus (T2DM) of the main SGLT2 inhibitors approved or currently in development, and provide a rationale for their use in T2DM. Despite the very promising characteristics of this new therapeutic class, a number of issues await consideration. One important question is what to expect from head-to-head comparison data. We also need to know if dual inhibition of SGLT1/SGLT2 is more efficacious in reducing HbA1c and how this therapy affects metabolic and cardiovascular parameters. Additionally, several SGLT2 agents that have not yet come to market have hitherto been evaluated in Asian populations, whereas approved SGLT2 inhibitors have been frequently studied in other populations, including Caucasian subjects. Thus, we need more information on the potential role of ethnicity on their efficacy and safety.
Main Ethiopian Rift Kinematic analogue modeling: Implications for Nubian-Somalian plate motion.
NASA Astrophysics Data System (ADS)
Erbello, A.; Corti, G.; Sani, F.; Agostini, A.; Buccianti, A.; Kidane, T. B.
2016-12-01
In this contribution, analogue modeling is used to provide new insights into the kinematics of the Nubia and Somalia plates responsible for development and evolution of the Main Ethiopian Rift (MER), at the northern termination of the East African Rift. In particular, we performed new crustal-scale, brittle models to analyze the along-strike variations in fault architecture in the MER and their relations with the rift trend, plate motion and the resulting Miocene-recent kinematics of rifting. The models reproduced the overall geometry of the 600km-long MER with its along-strike variation in orientation to test different hypothesis proposed to explain rift evolution. Analysis of model results in terms of statistics of fault length and orientation, as well as deformation architecture, and its comparison with the MER suggests that models of two-phase rifting (with a first phase of NW-SE extension followed by E-W rifting) or constant NW-SE extension, as well as models of constant ENE-WSW rifting are not able to reproduce the fault architecture observed in nature. Model results suggest instead that the rift has likely developed under a constant, post-11 Ma extension oriented roughly ESE-WNW (N97.5°E), consistent with recent plate kinematics models.
NASA Astrophysics Data System (ADS)
Erbello, Asfaw; Corti, Giacomo; Agostini, Andrea; Sani, Federico; Kidane, Tesfaye; Buccianti, Antonella
2016-12-01
In this contribution, analogue modeling is used to provide new insights into the Nubia-Somalia kinematics responsible for development and evolution of the Main Ethiopian Rift (MER), at the northern termination of the East African Rift system. In particular, we performed new crustal-scale, brittle models to analyze the along-strike variations in fault architecture in the MER and their relations with the rift trend, plate motion and the resulting Miocene-recent kinematics of rifting. The models reproduced the overall geometry of the ∼600 km-long MER with its along-strike variation in orientation to test different hypothesis proposed to explain rift evolution. Analysis of model results in terms of statistics of fault length and orientation, as well as deformation architecture, and its comparison with the MER suggest that models of two-phase rifting (with a first phase of NW-SE extension followed by E-W rifting) or constant NW-SE extension, as well as models of constant ENE-WSW rifting are not able to reproduce the fault architecture observed in nature. Model results suggest instead that the rift has likely developed under a constant, post-11 Ma extension oriented roughly ESE-WNW (N97.5°E), consistent with recent plate kinematics models.
A two dimensional power spectral estimate for some nonstationary processes. M.S. Thesis
NASA Technical Reports Server (NTRS)
Smith, Gregory L.
1989-01-01
A two dimensional estimate for the power spectral density of a nonstationary process is being developed. The estimate will be applied to helicopter noise data which is clearly nonstationary. The acoustic pressure from the isolated main rotor and isolated tail rotor is known to be periodically correlated (PC) and the combined noise from the main and tail rotors is assumed to be correlation autoregressive (CAR). The results of this nonstationary analysis will be compared with the current method of assuming that the data is stationary and analyzing it as such. Another method of analysis is to introduce a random phase shift into the data as shown by Papoulis to produce a time history which can then be accurately modeled as stationary. This method will also be investigated for the helicopter data. A method used to determine the period of a PC process when the period is not know is discussed. The period of a PC process must be known in order to produce an accurate spectral representation for the process. The spectral estimate is developed. The bias and variability of the estimate are also discussed. Finally, the current method for analyzing nonstationary data is compared to that of using a two dimensional spectral representation. In addition, the method of phase shifting the data is examined.
NASA Astrophysics Data System (ADS)
Fagundes, P. R.; Cardoso, F. A.; Fejer, B. G.; Kavutarapu, V.; Ribeiro, B. A.; Pillat, V. G.
2015-12-01
Fagundes PR, Cardoso FA and Venkatesh KPhysics and Astronomy Laboratory, Universidade do Vale do Paraiba (UNIVAP), Sao Jose dos Campos, Sao Paulo, Brazil In the present investigation we discuss the results on the response of the ionosphere (F-region) in the Brazilian sector, during extreme space weather event of March 2015. This geomagnetic storm has been considered as one of strongest storms in the solar cycle 24 where, the Dst index reached a minimum of -227 nT at 23:00 UT (17/03/2015) with KP reaching to 8-, and the monthly mean F10.7 solar flux was 125 sfu. This space weather event was studied using a large network of 110 GPS stations. It has been noticed that the Total Electron Content (TEC) was severely disturbed during the geomagnetic storm main and recovery phases. A wavelike oscillation with three peaks is observed from equator to low latitudes during the storm main phase on 17th and 18th March, 2015. Using a latitudinal chain of 8 GPS stations from equatorial region to low latitudes the storm time behavior of the Equatorial Ionization Anomaly (EIA) is investigated. It was noticed that the wavelike oscillation peak latitudinal extent decreases from the beginning of main phase to the recovery phase. The first maximum extends beyond from 2oS to 20oS, the second one from 8oS to 18oS and the third one from 13oS to 17oS. In addition, a strong negative phase in TEC variations is observed during the recovery phase on March 18, 2015. This negative phase is found to be stronger at low-latitude compared to the equatorial region. An anomalous behavior of EIA caused by the wavelike oscillations is observed during the main phase on March 17, 2015. Also, due to the strong negative phase in TEC resulted in strong EIA suppression on March 18, 2015.
Pires, Ana Paula Salum; De Oliveira, Carolina Dizioli Rodrigues; Moura, Sidnei; Dörr, Felipe Augusto; Silva, Wagner Abreu E; Yonamine, Mauricio
2009-01-01
Ayahuasca is obtained by infusing the pounded stems of Banisteriopsis caapi in combination with the leaves of Psychotria viridis. P. viridis is rich in the psychedelic indole N,N-dimethyltryptamine, whereas B. caapi contains substantial amounts of beta-carboline alkaloids, mainly harmine, harmaline and tetrahydroharmine, which are monoamine-oxidase inhibitors. Because of differences in composition in ayahuasca preparations, a method to measure their main active constituents is needed. To develop a gas chromatographic method for the simultaneous determination of dimethyltryptamine and the main beta-carbolines found in ayahuasca preparations. The alkaloids were extracted by means of solid phase extraction (C(18)) and detected by gas chromatography with nitrogen/phosphorous detector. The lower limit of quantification (LLOQ) was 0.02 mg/mL for all analytes. The calibration curves were linear over a concentration range of 0.02-4.0 mg/mL (r(2 )> 0.99). The method was also precise (RSD < 10%). A simple gas chromatographic method to determine the main alkaloids found in ayahuasca was developed and validated. The method can be useful to estimate administered doses in animals and humans for further pharmacological and toxicological investigations of ayahuasca. Copyright (c) 2009 John Wiley & Sons, Ltd.
Dai, Wenting; Dong, Jihong; Yan, Wanglin; Xu, Jiren
2017-01-01
The paper divided the whole coal life cycle, explained each phase characteristics, and took coal mine in China as a study case to assess the ecological risk in coal utilization phase. The main conclusions are as follows: (1) the whole coal life cycle is divided into coal mining, processing, transportation, utilization, and waste disposal. (2) The key points of production organization and characteristics in the five phases have great differences. The coal mining phase is characterized by the damage of the key ecological factors (water, soil, atmosphere, vegetation, etc.) damaged while the coal processing phase by discharging waste. The characteristics in coal transportation phase mainly performance as escaping and migration of atmospheric pollutants. In coal utilization phase, the main characteristics are aggravation of greenhouse effect. The main characteristics of waste disposal phase are accumulation of negative ecological effects on the land. (3) The ecological risk of soil heavy metals is serious in coal utilization phase. The potential ecological hazard coefficients of Pb and As in coal, residue and ash are all lower than 40, presenting low environmental impact on soil; the potential ecological risk coefficients of Cd are higher than 60, nearly half of their potential ecological risk coefficients are higher than 160, which presents high environmental pollution impact on soil; Hg's potential ecological risk coefficients are higher than 320, presenting the highest environmental pollution impact on soil; the comprehensive pollution indexes in coal, residue, and ash are relatively high, which means the pollution hazard potential to soil environment is high. (4) The ecological risk of the atmospheric solid suspended matter is relatively strong in coal utilization phase. The ecological risk of Cd and As in primary flue gas is both lower than net flue gas. The geoaccumulation indexes of Cd and Hg in primary flue gas and net flue gas are both higher than 5, presenting the very strong ecological risk; 50 % of the geoaccumulation index values of As are between 3 and 4, which has also presenting a strong ecological risk while Pb does not present the ecological risk characterization.
1st Stage Separation Aerodynamics Of VEGA Launcher
NASA Astrophysics Data System (ADS)
Genito, M.; Paglia, F.; Mogavero, A.; Barbagallo, D.
2011-05-01
VEGA is an European launch vehicle under development by the Prime Contractor ELV S.p.A. in the frame of an ESA contract. It is constituted by four stages, dedicated to the scientific/commercial market of small satellites (300 ÷ 2500 kg) into Low Earth Orbits, with inclinations ranging from 5.2° up to Sun Synchronous Orbits and with altitude ranging from 300 to 1500 km. Aim of this paper is to present a study of flow field due to retro-rockets impingement during the 1st stage VEGA separation phase. In particular the main goal of the present work is to present the aerodynamic activities performed for the justification of the separation phase.
Contact line motion over substrates with spatially non-uniform properties
NASA Astrophysics Data System (ADS)
Ajaev, Vladimir; Gatapova, Elizaveta; Kabov, Oleg
2017-11-01
We develop mathematical models of moving contact lines over flat solid surfaces with spatial variation of temperature and wetting properties under the conditions when evaporation is significant. The gas phase is assumed to be pure vapor and a lubrication-type framework is employed for describing viscous flow in the liquid. Marangoni stresses at the liquid surface arise as a result of temperature variation in the vapor phase, non-equilibrium effects during evaporation at the interface, and Kelvin effect. The relative importance of these three factors is determined. Variation of wetting properties is modeled through a two-component disjoining pressure, with the main focus on spatially periodic patterns leading to time-periodic variation of the contact line speed.
PRay - A graphical user interface for interactive visualization and modification of rayinvr models
NASA Astrophysics Data System (ADS)
Fromm, T.
2016-01-01
PRay is a graphical user interface for interactive displaying and editing of velocity models for seismic refraction. It is optimized for editing rayinvr models but can also be used as a dynamic viewer for ray tracing results from other software. The main features are the graphical editing of nodes and fast adjusting of the display (stations and phases). It can be extended by user-defined shell scripts and links to phase picking software. PRay is open source software written in the scripting language Perl, runs on Unix-like operating systems including Mac OS X and provides a version controlled source code repository for community development (https://sourceforge.net/projects/pray-plot-rayinvr/).
Sentinel-4: the geostationary component of the GMES atmosphere monitoring missions
NASA Astrophysics Data System (ADS)
Bazalgette Courrèges-Lacoste, G.; Arcioni, M.; Meijer, Y.; Bézy, J.-L.; Bensi, P.; Langen, J.
2017-11-01
The implementation of operational atmospheric composition monitoring missions is foreseen in the context of the Global Monitoring for Environment and Security (GMES) initiative. Sentinel-4 will address the geostationary observations and Sentinel-5 the low Earth orbit ones. The two missions are planned to be launched on-board Eumetsat's Meteosat Third Generation (MTG) and Post-EPS satellites, respectively. This paper presents an overview of the GMES Sentinel- 4 mission, which has been assessed at Phase-0 level. It describes the key requirements and outlines the main aspects of the candidate implementation concepts available at completion of Phase-0. The paper will particularly focus on the observation mode, the estimated performance and the related technology developments.
STS propellant scavenging systems study. Part 2, volume 1: Executive summary and study results
NASA Technical Reports Server (NTRS)
Williams, Frank L.
1987-01-01
The major objective of the STS Propellant Scavenging Study is to define the hardware, operations, and life cycle costs for recovery of unused Space Transportation System propellants. Earlier phases were concerned exclusively with the recovery of cryogenic propellants from the main propulsion system of the manned STS. The phase of the study covered by this report (Part II Extension) modified the objectives to include cryogenic propellants delivered to orbit by the unmanned cargo vehicle. The Part II Extension had the following objectives: (1) predict OTV propellant requirements from 1995 to 2010; investigate scavenging/transport tank reuse; determine optimum tank sizing and arrangement; and develop hardware concepts for tanks.
NASA Astrophysics Data System (ADS)
Ponce-Lee, E. L.; Olivares-Pérez, A.; Fuentes-Tapia, I.
2004-06-01
Computer holograms made with sugar crystals are reported. This material is well known as a good sweetener; the sugar from sugar cane or sugar beet (sucrose). These sweetener can be applied as honey "water and diluted sugar" easily on any substrate such as plastics or glasses without critical conditions for developed process. This step corresponds only to the cured sucrose as a photopolymer process. The maximum absorption spectra is localized at UV region λ=240 nm. We record with lithographic techniques some gratings, showing a good diffraction efficiency around 45%. This material has good resolution to make diffraction gratings. These properties are attractive because they open the possibility to make phase holograms on candies. Mainly the phase modulation is by refraction index.
Parachute dynamics and stability analysis. [using nonlinear differential equations of motion
NASA Technical Reports Server (NTRS)
Ibrahim, S. K.; Engdahl, R. A.
1974-01-01
The nonlinear differential equations of motion for a general parachute-riser-payload system are developed. The resulting math model is then applied for analyzing the descent dynamics and stability characteristics of both the drogue stabilization phase and the main descent phase of the space shuttle solid rocket booster (SRB) recovery system. The formulation of the problem is characterized by a minimum number of simplifying assumptions and full application of state-of-the-art parachute technology. The parachute suspension lines and the parachute risers can be modeled as elastic elements, and the whole system may be subjected to specified wind and gust profiles in order to assess their effects on the stability of the recovery system.
Alteration of Hormonal Levels in a Rootless Epiphytic Bromeliad in Different Phenological Phases.
Mercier; Endres
1999-11-01
Major changes in indole-3-acetic acid (IAA) and cytokinin (CK) levels occur at different phenological phases of Tillandsia recurvata shoots. This epiphytic rootless bromeliad was chosen as suitable material for hormonal analysis because CK synthesis is restricted to the shoots, thus avoiding problems in the interpretation of results caused by translocation and interconversion of CK forms between roots and leaves encountered in plants with both organs. Young plants of T. recurvata have weak apical dominance because side shoots appeared early in development, and branch growth was correlated with a strong increase in the level of zeatin. The flowering phase was characterized by a significant increase in free base CKs, zeatin, and isopentenyladenine compared with the levels found in adult vegetative shoots. In contrast, both free-base CKs declined in the fruiting phenological phase, and the IAA level increased dramatically. It was concluded that in phases characterized by intense organ formation, such as in the juvenile and flowering stages, there was an enhancement of CK content, mainly caused by zeatin, leading to a lower IAA/CK ratio. Higher ratios were correlated with phases that showed no organogenesis, such as adult and fruiting phenologies.
Learning by observation: insights from Williams syndrome.
Foti, Francesca; Menghini, Deny; Mandolesi, Laura; Federico, Francesca; Vicari, Stefano; Petrosini, Laura
2013-01-01
Observing another person performing a complex action accelerates the observer's acquisition of the same action and limits the time-consuming process of learning by trial and error. Observational learning makes an interesting and potentially important topic in the developmental domain, especially when disorders are considered. The implications of studies aimed at clarifying whether and how this form of learning is spared by pathology are manifold. We focused on a specific population with learning and intellectual disabilities, the individuals with Williams syndrome. The performance of twenty-eight individuals with Williams syndrome was compared with that of mental age- and gender-matched thirty-two typically developing children on tasks of learning of a visuo-motor sequence by observation or by trial and error. Regardless of the learning modality, acquiring the correct sequence involved three main phases: a detection phase, in which participants discovered the correct sequence and learned how to perform the task; an exercise phase, in which they reproduced the sequence until performance was error-free; an automatization phase, in which by repeating the error-free sequence they became accurate and speedy. Participants with Williams syndrome beneficiated of observational training (in which they observed an actor detecting the visuo-motor sequence) in the detection phase, while they performed worse than typically developing children in the exercise and automatization phases. Thus, by exploiting competencies learned by observation, individuals with Williams syndrome detected the visuo-motor sequence, putting into action the appropriate procedural strategies. Conversely, their impaired performances in the exercise phases appeared linked to impaired spatial working memory, while their deficits in automatization phases to deficits in processes increasing efficiency and speed of the response. Overall, observational experience was advantageous for acquiring competencies, since it primed subjects' interest in the actions to be performed and functioned as a catalyst for executed action.
Developing a patient-led electronic feedback system for quality and safety within Renal PatientView.
Giles, Sally J; Reynolds, Caroline; Heyhoe, Jane; Armitage, Gerry
2017-03-01
It is increasingly acknowledged that patients can provide direct feedback about the quality and safety of their care through patient reporting systems. The aim of this study was to explore the feasibility of patients, healthcare professionals and researchers working in partnership to develop a patient-led quality and safety feedback system within an existing electronic health record (EHR), known as Renal PatientView (RPV). Phase 1 (inception) involved focus groups (n = 9) and phase 2 (requirements) involved cognitive walkthroughs (n = 34) and 1:1 qualitative interviews (n = 34) with patients and healthcare professionals. A Joint Services Expert Panel (JSP) was convened to review the findings from phase 1 and agree the core principles and components of the system prototype. Phase 1 data were analysed using a thematic approach. Data from phase 1 were used to inform the design of the initial system prototype. Phase 2 data were analysed using the components of heuristic evaluation, resulting in a list of core principles and components for the final system prototype. Phase 1 identified four main barriers and facilitators to patients feeding back on quality and safety concerns. In phase 2, the JSP agreed that the system should be based on seven core principles and components. Stakeholders were able to work together to identify core principles and components for an electronic patient quality and safety feedback system in renal services. Tensions arose due to competing priorities, particularly around anonymity and feedback. Careful consideration should be given to the feasibility of integrating a novel element with differing priorities into an established system with existing functions and objectives. © 2016 European Dialysis and Transplant Nurses Association/European Renal Care Association.
Hard x-ray phase contrastmicroscopy - techniques and applications
NASA Astrophysics Data System (ADS)
Holzner, Christian
In 1918, Einstein provided the first description of the nature of the refractive index for X-rays, showing that phase contrast effects are significant. A century later, most x-ray microscopy and nearly all medical imaging remains based on absorption contrast, even though phase contrast offers orders of magnitude improvements in contrast and reduced radiation exposure at multi-keV x-ray energies. The work presented is concerned with developing practical and quantitative methods of phase contrast for x-ray microscopy. A theoretical framework for imaging in phase contrast is put forward; this is used to obtain quantitative images in a scanning microscope using a segmented detector, and to correct for artifacts in a commercial phase contrast x-ray nano-tomography system. The principle of reciprocity between scanning and full-field microscopes is then used to arrive at a novel solution: Zernike contrast in a scanning microscope. These approaches are compared on a theoretical and experimental basis in direct connection with applications using multi-keV x-ray microscopes at the Advanced Photon Source at Argonne National Laboratory. Phase contrast provides the best means to image mass and ultrastructure of light elements that mainly constitute biological matter, while stimulated x-ray fluorescence provides high sensitivity for studies of the distribution of heavier trace elements, such as metals. These approaches are combined in a complementary way to yield quantitative maps of elemental concentration from 2D images, with elements placed in their ultrastructural context. The combination of x-ray fluorescence and phase contrast poses an ideal match for routine, high resolution tomographic imaging of biological samples in the future. The presented techniques and demonstration experiments will help pave the way for this development.
Exploring Residents’ Communication Learning Process in the Workplace: A Five-Phase Model
Scherpbier, Albert; van Dulmen, Sandra
2015-01-01
Context Competency-based education is a resurgent paradigm in professional medical education. However, more specific knowledge is needed about the learning process of such competencies, since they consist of complex skills. We chose to focus on the competency of skilled communication and want to further explore its learning process, since it is regarded as a main competency in medical education. Objective This study aims to explore in more detail the learning process that residents in general practice go through during workplace-based learning in order to become skilled communicators. Methods A qualitative study was conducted in which twelve GP residents were observed during their regular consultations, and were interviewed in-depth afterwards. Results Analysis of the data resulted in the construction of five phases and two overall conditions to describe the development towards becoming a skilled communicator: Confrontation with (un)desired behaviour or clinical outcomes was the first phase. Becoming conscious of one’s own behaviour and changing the underlying frame of reference formed the second phase. The third phase consisted of the search for alternative behaviour. In the fourth phase, personalization of the alternative behaviour had to occur, this was perceived as difficult and required much time. Finally, the fifth phase concerned full internalization of the new behaviour, which by then had become an integrated part of the residents’ clinical repertoire. Safety and cognitive & emotional space were labelled as overall conditions influencing this learning process. Conclusions Knowledge and awareness of these five phases can be used to adjust medical working and learning environments in such a way that development of skilled medical communication can come to full fruition and its benefits are more fully reaped. PMID:26000767
NASA Technical Reports Server (NTRS)
Yoerkie, Charles A.; Gintoli, P. J.; Ingraham, S. T.; Moore, J. A.
1986-01-01
The goal of this research is the understanding of helicopter internal noise mechanisms and the development, design, and testing of noise control concepts which will produce significant reductions in the acoustic environment to which passengers are exposed. The Phase 3 effort involved the identification and evaluation of current and advanced treatment concepts, including isolation of structure-borne paths. In addition, a plan was devised for the full-scale evaluation of an isolation concept. Specific objectives were as follows: (1) identification and characterization of various noise control concepts; (2) implementation of noise control concepts within the S-76 SEA (statistical energy analysis) model; (3) definition and evaluation of a preliminary acoustic isolation design to reduce structure-borne transmission of acoustic frequency main gearbox gear clash vibrations into the airframe; (4) formulation of a plan for the full-scale validation of the isolation concept; and (5) prediction of the cabin noise environment with various noise control concepts installed.
SEDHI: development status of the Pléiades detection electronics
NASA Astrophysics Data System (ADS)
Dantes, Didier; Biffi, Jean-Marc; Neveu, Claude; Renard, Christophe
2017-11-01
In the framework of the Pléiades program, Alcatel Space is developping with CNES a new concept of Highly Integrated Detection Electronic Subsystem (SEDHI) which lead to very high gains in term of camera mass, volume and power consumption. This paper presents the design of this new concept and summarizes its main performances. The electrical, mechanical and thermal aspects of the SEDHI concept are described, including the basic technologies: panchromatic detector, multispectral detector, butting technology, ASIC for phase shift of detector clocks, ASIC for video processing, ASIC for phase trimming, hybrids, video modules... This concept and these technologies can be adapted to a large scale of missions and instruments. Design, performance and budgets of the subsystem are given for the Pléiades mission for which the SEDHI concept has been selected. The detailed performances of each critical component are provided, focusing on the most critical performances which have been obtained at this level of the Pléiades development.
Summary Document: Restoration Plan for Major Airports after a Bioterrorist Attack
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raber, E
2007-01-11
This document provides general guidelines for developing a Restoration Plan for a major airport following release of a biological warfare agent. San Francisco International Airport was selected as the example airport during development of the Plan to illustrate specific details. The spore forming bacterium Bacillus anthracis was selected as the biological agent of primary concern because it is the most difficult of known bioterrorism agents to inactivate and is considered to be one of the agents most likely to be used as a biological weapon. The focus of the Plan is on activities associated with the Characterization, Remediation, and Clearancemore » Phases that are defined herein. Activities associated with the Notification and First-Response Phases are briefly discussed in Appendixes A and B, respectively. In addition to the main text of this Plan and associated appendixes, a data supplement was developed specifically for San Francisco International Airport. Requests for the data supplement must be made directly to the Emergency Planning Operations Division of San Francisco International Airport.« less
Composite load spectra for select space propulsion structural components
NASA Technical Reports Server (NTRS)
Newell, J. F.; Ho, H. W.; Kurth, R. E.
1991-01-01
The work performed to develop composite load spectra (CLS) for the Space Shuttle Main Engine (SSME) using probabilistic methods. The three methods were implemented to be the engine system influence model. RASCAL was chosen to be the principal method as most component load models were implemented with the method. Validation of RASCAL was performed. High accuracy comparable to the Monte Carlo method can be obtained if a large enough bin size is used. Generic probabilistic models were developed and implemented for load calculations using the probabilistic methods discussed above. Each engine mission, either a real fighter or a test, has three mission phases: the engine start transient phase, the steady state phase, and the engine cut off transient phase. Power level and engine operating inlet conditions change during a mission. The load calculation module provides the steady-state and quasi-steady state calculation procedures with duty-cycle-data option. The quasi-steady state procedure is for engine transient phase calculations. In addition, a few generic probabilistic load models were also developed for specific conditions. These include the fixed transient spike model, the poison arrival transient spike model, and the rare event model. These generic probabilistic load models provide sufficient latitude for simulating loads with specific conditions. For SSME components, turbine blades, transfer ducts, LOX post, and the high pressure oxidizer turbopump (HPOTP) discharge duct were selected for application of the CLS program. They include static pressure loads and dynamic pressure loads for all four components, centrifugal force for the turbine blade, temperatures of thermal loads for all four components, and structural vibration loads for the ducts and LOX posts.
A Generalised Fault Protection Structure Proposed for Uni-grounded Low-Voltage AC Microgrids
NASA Astrophysics Data System (ADS)
Bui, Duong Minh; Chen, Shi-Lin; Lien, Keng-Yu; Jiang, Jheng-Lun
2016-04-01
This paper presents three main configurations of uni-grounded low-voltage AC microgrids. Transient situations of a uni-grounded low-voltage (LV) AC microgrid (MG) are simulated through various fault tests and operation transition tests between grid-connected and islanded modes. Based on transient simulation results, available fault protection methods are proposed for main and back-up protection of a uni-grounded AC microgrid. In addition, concept of a generalised fault protection structure of uni-grounded LVAC MGs is mentioned in the paper. As a result, main contributions of the paper are: (i) definition of different uni-grounded LVAC MG configurations; (ii) analysing transient responses of a uni-grounded LVAC microgrid through line-to-line faults, line-to-ground faults, three-phase faults and a microgrid operation transition test, (iii) proposing available fault protection methods for uni-grounded microgrids, such as: non-directional or directional overcurrent protection, under/over voltage protection, differential current protection, voltage-restrained overcurrent protection, and other fault protection principles not based on phase currents and voltages (e.g. total harmonic distortion detection of currents and voltages, using sequence components of current and voltage, 3I0 or 3V0 components), and (iv) developing a generalised fault protection structure with six individual protection zones to be suitable for different uni-grounded AC MG configurations.
Phase Behavior of Binary Blends of AB+AC Block Copolymers with compatible B and C blocks
NASA Astrophysics Data System (ADS)
Pryamitsyn, Victor; Ganesan, Venkat
2012-02-01
Recently the experimental studies of phase behavior of binary blends of PS-b-P2VP and PS-b-PHS demonstrated an interesting effect: blends of symmetric PS-b-P2VP and shorter symmetric (PS-b-PHS) formed cylindrical HEX and spherical BCC phases, while each pure component formed lamellas. The miscibility of P2VP and PHS is caused by the hydrogen bonding between P2VP and PHS,which can be described as a negative Flory ?-parameter between P2VP and PHS. We developed a theory of the microphase segregation of AB+AC blends of diblock copolymers based on strong stretching theory. The main result of our theory is that in the copolymer brush-like layer formed by longer B chain and shorter C chains, the attraction between B and shorter C chains causes relative stretching of short C chains and compression of longer B chains. The latter manifests in an excessive bending force towards the grafting surface (BC|AA interface). Such bending force causes a transition from a symmetric lamella phase to a HEX cylinder or BCC spherical phases with the BC phase being a ``matrix'' component. In a blend of asymmetric BCC sphere forming copolymers (where B and C segments are the minor components), such bending force may unfold BCC spherical phase to a HEX cylinder phase, or even highly uneven lamella phases.
Yuhara, Daisuke; Brumby, Paul E; Wu, David T; Sum, Amadeu K; Yasuoka, Kenji
2018-05-14
To develop prediction methods of three-phase equilibrium (coexistence) conditions of methane hydrate by molecular simulations, we examined the use of NVT (isometric-isothermal) molecular dynamics (MD) simulations. NVT MD simulations of coexisting solid hydrate, liquid water, and vapor methane phases were performed at four different temperatures, namely, 285, 290, 295, and 300 K. NVT simulations do not require complex pressure control schemes in multi-phase systems, and the growth or dissociation of the hydrate phase can lead to significant pressure changes in the approach toward equilibrium conditions. We found that the calculated equilibrium pressures tended to be higher than those reported by previous NPT (isobaric-isothermal) simulation studies using the same water model. The deviations of equilibrium conditions from previous simulation studies are mainly attributable to the employed calculation methods of pressure and Lennard-Jones interactions. We monitored the pressure in the methane phase, far from the interfaces with other phases, and confirmed that it was higher than the total pressure of the system calculated by previous studies. This fact clearly highlights the difficulties associated with the pressure calculation and control for multi-phase systems. The treatment of Lennard-Jones interactions without tail corrections in MD simulations also contributes to the overestimation of equilibrium pressure. Although improvements are still required to obtain accurate equilibrium conditions, NVT MD simulations exhibit potential for the prediction of equilibrium conditions of multi-phase systems.
NASA Astrophysics Data System (ADS)
Yuhara, Daisuke; Brumby, Paul E.; Wu, David T.; Sum, Amadeu K.; Yasuoka, Kenji
2018-05-01
To develop prediction methods of three-phase equilibrium (coexistence) conditions of methane hydrate by molecular simulations, we examined the use of NVT (isometric-isothermal) molecular dynamics (MD) simulations. NVT MD simulations of coexisting solid hydrate, liquid water, and vapor methane phases were performed at four different temperatures, namely, 285, 290, 295, and 300 K. NVT simulations do not require complex pressure control schemes in multi-phase systems, and the growth or dissociation of the hydrate phase can lead to significant pressure changes in the approach toward equilibrium conditions. We found that the calculated equilibrium pressures tended to be higher than those reported by previous NPT (isobaric-isothermal) simulation studies using the same water model. The deviations of equilibrium conditions from previous simulation studies are mainly attributable to the employed calculation methods of pressure and Lennard-Jones interactions. We monitored the pressure in the methane phase, far from the interfaces with other phases, and confirmed that it was higher than the total pressure of the system calculated by previous studies. This fact clearly highlights the difficulties associated with the pressure calculation and control for multi-phase systems. The treatment of Lennard-Jones interactions without tail corrections in MD simulations also contributes to the overestimation of equilibrium pressure. Although improvements are still required to obtain accurate equilibrium conditions, NVT MD simulations exhibit potential for the prediction of equilibrium conditions of multi-phase systems.
Zahiruddin, Wan Mohd; Arifin, Wan Nor; Mohd-Nazri, Shafei; Sukeri, Surianti; Zawaha, Idris; Bakar, Rahman Abu; Hamat, Rukman Awang; Malina, Osman; Jamaludin, Tengku Zetty Maztura Tengku; Pathman, Arumugam; Mas-Harithulfadhli-Agus, Ab Rahman; Norazlin, Idris; Suhailah, Binti Samsudin; Saudi, Siti Nor Sakinah; Abdullah, Nurul Munirah; Nozmi, Noramira; Zainuddin, Abdul Wahab; Aziah, Daud
2018-03-07
In Malaysia, leptospirosis is considered an endemic disease, with sporadic outbreaks following rainy or flood seasons. The objective of this study was to develop and validate a new knowledge, attitude, belief and practice (KABP) questionnaire on leptospirosis for use in urban and rural populations in Malaysia. The questionnaire comprised development and validation stages. The development phase encompassed a literature review, expert panel review, focus-group testing, and evaluation. The validation phase consisted of exploratory and confirmatory parts to verify the psychometric properties of the questionnaire. A total of 214 and 759 participants were recruited from two Malaysian states, Kelantan and Selangor respectively, for the validation phase. The participants comprised urban and rural communities with a high reported incidence of leptospirosis. The knowledge section of the validation phase utilized item response theory (IRT) analysis. The attitude and belief sections utilized exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The development phase resulted in a questionnaire that included four main sections: knowledge, attitude, belief, and practice. In the exploratory phase, as shown by the IRT analysis of knowledge about leptospirosis, the difficulty and discrimination values of the items were acceptable, with the exception of two items. Based on the EFA, the psychometric properties of the attitude, belief, and practice sections were poor. Thus, these sections were revised, and no further factor analysis of the practice section was conducted. In the confirmatory stage, the difficulty and discrimination values of the items in the knowledge section remained within the acceptable range. The CFA of the attitude section resulted in a good-fitting two-factor model. The CFA of the belief section retained low number of items, although the analysis resulted in a good fit in the final three-factor model. Based on the IRT analysis and factor analytic evidence, the knowledge and attitude sections of the KABP questionnaire on leptospirosis were psychometrically valid. However, the psychometric properties of the belief section were unsatisfactory, despite being revised after the initial validation study. Further development of this section is warranted in future studies.
THE LIGHT CURVE OF HERCULES X-1 AS OBSERVED BY THE ROSSI X-RAY TIMING EXPLORER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leahy, D. A.; Igna, Ciprian, E-mail: leahy@ucalgary.ca
2011-07-20
Analysis of the light curve of Hercules X-1 using the full set of archival observations of Hercules X-1 by the Rossi X-Ray Timing Explorer/Proportional Counter Array (RXTE/PCA) is reported. The observations cover time periods that Her X-1 is in main high, short high, and low states, and an anomalous low state (ALS). They include over 1.4 Ms of net exposure time. We present 35 day and orbital phase folded light curves of the count rates and softness ratios, showing the range of behaviors of Her X-1 with the high sensitivity of the RXTE/PCA. New phenomena are uncovered and previous phenomenamore » are seen in greater detail. For both main high and short high states, the fraction of time in dips is found to be a function of orbital phase and of 35 day phase. It increases steadily with orbital phase past orbital phase 0.3 and is higher at the start and end of both main high and short high states. It is higher for short high state (62%) than for main high state (28%). The normal low state data and ALS data are compared: the low state count rate is {approx}twice as high as for ALS data. The 2-4 keV to 9-20 keV softness ratio changes smoothly with orbital phase for low states and ALSs, and is indistinguishable between the two, yet very different than for the high states. This supports models for which the cause of the ALS is changed disk geometry that prevents a direct line of sight from neutron star to observer at all 35 day phases.« less
NASA Astrophysics Data System (ADS)
Kitanovski, Z.; Čusak, A.; Grgić, I.; Claeys, M.
2014-08-01
Guaiacol (2-methoxyphenol) and its derivatives can be emitted into the atmosphere by thermal degradation (i.e., burning) of wood lignins. Due to its volatility, guaiacol is predominantly distributed atmospherically in the gaseous phase. Recent studies have shown the importance of aqueous-phase reactions in addition to the dominant gas-phase and heterogeneous reactions of guaiacol, in the formation of secondary organic aerosol (SOA) in the atmosphere. The main objectives of the present study were to chemically characterize the main products of the aqueous-phase photonitration of guaiacol and examine their possible presence in urban atmospheric aerosols. The aqueous-phase reactions were carried out under simulated sunlight and in the presence of hydrogen peroxide and nitrite. The formed guaiacol reaction products were concentrated by solid-phase extraction and then purified with semi-preparative high-performance liquid chromatography (HPLC). The fractionated individual compounds were isolated as pure solids and further analyzed with liquid-state proton, carbon-13 and two-dimensional nuclear magnetic resonance (NMR) spectroscopy, and direct infusion negative ion electrospray ionization tandem mass spectrometry ((-)ESI-MS/MS). The NMR and product ion (MS2) spectra were used for unambiguous product structure elucidation. The main products of guaiacol photonitration are 4-nitroguaiacol (4NG), 6-nitroguaiacol (6NG), and 4,6-dinitroguaiacol (4,6DNG). Using the isolated compounds as standards, 4NG and 4,6DNG were unambiguously identified in winter PM10 aerosols from the city of Ljubljana (Slovenia) by means of HPLC/(-)ESI-MS/MS. Owing to the strong absorption of ultraviolet and visible light, 4,6DNG could be an important constituent of atmospheric "brown" carbon, especially in regions affected by biomass burning.
Automatic Clustering of Rolling Element Bearings Defects with Artificial Neural Network
NASA Astrophysics Data System (ADS)
Antonini, M.; Faglia, R.; Pedersoli, M.; Tiboni, M.
2006-06-01
The paper presents the optimization of a methodology for automatic clustering based on Artificial Neural Networks to detect the presence of defects in rolling bearings. The research activity was developed in co-operation with an Italian company which is expert in the production of water pumps for automotive use (Industrie Saleri Italo). The final goal of the work is to develop a system for the automatic control of the pumps, at the end of the production line. In this viewpoint, we are gradually considering the main elements of the water pump, which can cause malfunctioning. The first elements we have considered are the rolling bearing, a very critic component for the system. The experimental activity is based on the vibration measuring of rolling bearings opportunely damaged; vibration signals are in the second phase elaborated; the third and last phase is an automatic clustering. Different signal elaboration techniques are compared to optimize the methodology.
NASA Technical Reports Server (NTRS)
Stoughton, R. M.
1990-01-01
A proposed methodology applicable to the design of manipulator systems is described. The current design process is especially weak in the preliminary design phase, since there is no accepted measure to be used in trading off different options available for the various subsystems. The design process described uses Cartesian End-Effector Impedance as a measure of performance for the system. Having this measure of performance, it is shown how it may be used to determine the trade-offs necessary to the preliminary design phase. The design process involves three main parts: (1) determination of desired system performance in terms of End-Effector Impedance; (2) trade-off design options to achieve this desired performance; and (3) verification of system performance through laboratory testing. The design process is developed using numerous examples and experiments to demonstrate the feasability of this approach to manipulator design.
Vortex Loops at the Superfluid Lambda Transition: An Exact Theory?
NASA Technical Reports Server (NTRS)
Williams, Gary A.
2003-01-01
A vortex-loop theory of the superfluid lambda transition has been developed over the last decade, with many results in agreement with experiments. It is a very simple theory, consisting of just three basic equations. When it was first proposed the main uncertainty in the theory was the use Flory scaling to find the fractal dimension of the random-walking vortex loops. Recent developments in high-resolution Monte Carlo simulations have now made it possible to verify the accuracy of this Flory-scaling assumption. Although the loop theory is not yet rigorously proven to be exact, the Monte Carlo results show at the least that it is an extremely good approximation. Recent loop calculations of the critical Casimir effect in helium films in the superfluid phase T < Tc will be compared with similar perturbative RG calculations in the normal phase T > Tc; the two calculations are found to match very nicely right at Tc.
A Hamiltonian approach to Thermodynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baldiotti, M.C., E-mail: baldiotti@uel.br; Fresneda, R., E-mail: rodrigo.fresneda@ufabc.edu.br; Molina, C., E-mail: cmolina@usp.br
In the present work we develop a strictly Hamiltonian approach to Thermodynamics. A thermodynamic description based on symplectic geometry is introduced, where all thermodynamic processes can be described within the framework of Analytic Mechanics. Our proposal is constructed on top of a usual symplectic manifold, where phase space is even dimensional and one has well-defined Poisson brackets. The main idea is the introduction of an extended phase space where thermodynamic equations of state are realized as constraints. We are then able to apply the canonical transformation toolkit to thermodynamic problems. Throughout this development, Dirac’s theory of constrained systems is extensivelymore » used. To illustrate the formalism, we consider paradigmatic examples, namely, the ideal, van der Waals and Clausius gases. - Highlights: • A strictly Hamiltonian approach to Thermodynamics is proposed. • Dirac’s theory of constrained systems is extensively used. • Thermodynamic equations of state are realized as constraints. • Thermodynamic potentials are related by canonical transformations.« less
NASA Technical Reports Server (NTRS)
Srivastava, Sadanand; deLamadrid, James
1998-01-01
The User System Interface Agent (USIA) is a special type of software agent which acts as the "middle man" between a human user and an information processing environment. USIA consists of a group of cooperating agents which are responsible for assisting users in obtaining information processing services intuitively and efficiently. Some of the main features of USIA include: (1) multiple interaction modes and (2) user-specific and stereotype modeling and adaptation. This prototype system provides us with a development platform towards the realization of an operational information ecology. In the first phase of this project we focus on the design and implementation of prototype system of the User-System Interface Agent (USIA). The second face of USIA allows user interaction via a restricted query language as well as through a taxonomy of windows. In third phase the USIA system architecture was revised.
Radiation Hard Silicon Particle Detectors for Phase-II LHC Trackers
NASA Astrophysics Data System (ADS)
Oblakowska-Mucha, A.
2017-02-01
The major LHC upgrade is planned after ten years of accelerator operation. It is foreseen to significantly increase the luminosity of the current machine up to 1035 cm-2s-1 and operate as the upcoming High Luminosity LHC (HL-LHC) . The major detectors upgrade, called the Phase-II Upgrade, is also planned, a main reason being the aging processes caused by severe particle radiation. Within the RD50 Collaboration, a large Research and Development program has been underway to develop silicon sensors with sufficient radiation tolerance for HL-LHC trackers. In this summary, several results obtained during the testing of the devices after irradiation to HL-LHC levels are presented. Among the studied structures, one can find advanced sensors types like 3D silicon detectors, High-Voltage CMOS technologies, or sensors with intrinsic gain (LGAD). Based on these results, the RD50 Collaboration gives recommendation for the silicon detectors to be used in the detector upgrade.
[Military psychiatry in Israel: a 50-year perspective].
Bleich, A
2000-05-01
The history of military psychiatry in Israel may be divided into 2 main periods. The first extended from the War of Independence in 1948, through the Sinai, Six Day and Yom Kippur Wars. Its outstanding feature was avoidance of the issue of combat stress reaction (CSR). The Yom Kippur War made the recognition of CSR inescapable, assisted in breaking up denial, and served as a stimulus for development of the next phase of the system. This second phase was characterized by impressive progress in all areas of military psychiatry. The rich experience accumulated during the wars, together with the assimilation of a research culture which began blooming, especially in the wake of the Lebanon War, aided the development and crystallization of concepts related to combat and non-combat military psychiatry alike. The build-up of the mental health organization overlapped field deployment of the Medical Corps.
Progress in superconductivity: The Indian Scenario
NASA Technical Reports Server (NTRS)
Multani, Manu; Mishra, V. K.
1995-01-01
India has made rapid progress in the field of high temperature superconductivity, beginning at the time of publication of the Zeitschrift fur Physik paper by Bednorz and Muller. Phase 1 of the program was conceived by the Department of Science & Technology of the Government of India. It consisted of 42 projects in the area of basic research, 23 projects in applications and 4 short-term demonstration studies. The second phase started in October 1991 and will run through March 1995. It consists of 50 basic research programs and 24 application programs. The total investment, mainly consisting of infrastructural development to supplement existing facilities and hiring younger people, has amounted to about Indian Rupees 40 crores, equivalent to about US$ 13 million. The expenditure for the period 1992-1997 shall be up to about Rs. 27 crores, equivalent to about US$ 9 million. The basic idea is to keep pace with developments around the world.
Radiopaque Strontium Fluoroapatite Glass-Ceramics.
Höland, Wolfram; Schweiger, Marcel; Dittmer, Marc; Ritzberger, Christian
2015-01-01
The controlled precipitation of strontium fluoroapatite crystals was studied in four base glass compositions derived from the SiO2-Al2O3-Y2O3-SrO-Na2O-K2O/Rb2O/Cs2O-P2O5-F system. The crystal phase formation of these glasses and the main properties of the glass-ceramics, such as thermal and optical properties and radiopacity were compared with a fifth, a reference glass-ceramic. The reference glass-ceramic was characterized as Ca-fluoroapatite glass-ceramic. The four strontium fluoroapatite glass-ceramics showed the following crystal phases: (a) Sr5(PO4)3F - leucite, KAlSi2O6, (b) Sr5(PO4)3F - leucite, KAlSi2O6, and nano-sized NaSrPO4, (c) Sr5(PO4)3F - pollucite, CsAlSi2O6, and nano-sized NaSrPO4, and (d) Sr5(PO4)3F - Rb-leucite, RbAlSi2O6, and nano-sized NaSrPO4. The proof of crystal phase formation was possible by X-ray diffraction. The microstructures, which were studied using scanning electron microscopy, demonstrated a uniform distribution of the crystals in the glass matrix. The Sr-fluoroapatites were precipitated based on an internal crystallization process, and the crystals demonstrated a needle-like morphology. The study of the crystal growth of needle-like Sr-fluoroapatites gave a clear evidence of an Ostwald ripening mechanism. The formation of leucite, pollucite, and Rb-leucite was based on a surface crystallization mechanism. Therefore, a twofold crystallization mechanism was successfully applied to develop these types of glass-ceramics. The main focus of this study was the controlled development of glass-ceramics exhibiting high radiopacity in comparison to the reference glass-ceramic. This goal could be achieved with all four glass-ceramics with the preferred development of the Sr-fluoroapatite - pollucite-type glass-ceramic. In addition to this main development, it was possible to control the thermal properties. Especially the Rb-leucite containing glass-ceramic showed the highest coefficient of thermal expansion (CTE). These glass-ceramics allow optical properties, especially the translucency and color, to be tailored to the needs of biomaterials for dental applications. The authors conclude that it is possible to use twofold crystallization processes to develop glass-ceramic biomaterials featuring different properties, such as specific radiopacity values, CTEs, and optical characteristics.
Radiopaque Strontium Fluoroapatite Glass-Ceramics
Höland, Wolfram; Schweiger, Marcel; Dittmer, Marc; Ritzberger, Christian
2015-01-01
The controlled precipitation of strontium fluoroapatite crystals was studied in four base glass compositions derived from the SiO2–Al2O3–Y2O3–SrO–Na2O–K2O/Rb2O/Cs2O–P2O5–F system. The crystal phase formation of these glasses and the main properties of the glass-ceramics, such as thermal and optical properties and radiopacity were compared with a fifth, a reference glass-ceramic. The reference glass-ceramic was characterized as Ca-fluoroapatite glass-ceramic. The four strontium fluoroapatite glass-ceramics showed the following crystal phases: (a) Sr5(PO4)3F – leucite, KAlSi2O6, (b) Sr5(PO4)3F – leucite, KAlSi2O6, and nano-sized NaSrPO4, (c) Sr5(PO4)3F – pollucite, CsAlSi2O6, and nano-sized NaSrPO4, and (d) Sr5(PO4)3F – Rb-leucite, RbAlSi2O6, and nano-sized NaSrPO4. The proof of crystal phase formation was possible by X-ray diffraction. The microstructures, which were studied using scanning electron microscopy, demonstrated a uniform distribution of the crystals in the glass matrix. The Sr-fluoroapatites were precipitated based on an internal crystallization process, and the crystals demonstrated a needle-like morphology. The study of the crystal growth of needle-like Sr-fluoroapatites gave a clear evidence of an Ostwald ripening mechanism. The formation of leucite, pollucite, and Rb-leucite was based on a surface crystallization mechanism. Therefore, a twofold crystallization mechanism was successfully applied to develop these types of glass-ceramics. The main focus of this study was the controlled development of glass-ceramics exhibiting high radiopacity in comparison to the reference glass-ceramic. This goal could be achieved with all four glass-ceramics with the preferred development of the Sr-fluoroapatite – pollucite-type glass-ceramic. In addition to this main development, it was possible to control the thermal properties. Especially the Rb-leucite containing glass-ceramic showed the highest coefficient of thermal expansion (CTE). These glass-ceramics allow optical properties, especially the translucency and color, to be tailored to the needs of biomaterials for dental applications. The authors conclude that it is possible to use twofold crystallization processes to develop glass-ceramic biomaterials featuring different properties, such as specific radiopacity values, CTEs, and optical characteristics. PMID:26528470
NASA Technical Reports Server (NTRS)
Ruf, Joseph H.
1992-01-01
Phase 2+ Space Shuttle Main Engine powerheads, E0209 and E0215 degraded their main combustion chamber (MCC) liners at a faster rate than is normal for phase 2 powerheads. One possible cause of the accelerated degradation was a reduction of coolant flow through the MCC. Hardware changes were made to the preburner fuel leg which may have reduced the resistance and, therefore, pulled some of the hydrogen from the MCC coolant leg. A computational fluid dynamics (CFD) analysis was performed to determine hydrogen flow path resistances of the phase 2+ fuel preburner injector elements relative to the phase 2 element. FDNS was implemented on axisymmetric grids with the hydrogen assumed to be incompressible. The analysis was performed in two steps: the first isolated the effect of the different inlet areas and the second modeled the entire injector element hydrogen flow path.
NASA Astrophysics Data System (ADS)
Kuchle, Juliano; Scherer, Claiton Marlon dos Santos; Born, Christian Correa; Alvarenga, Renata dos Santos; Adegas, Felipe
2011-04-01
The Dom João Stage comprises an interval with variable thickness between 100 and 1200 m, composed of fluvial, eolian and lacustrine deposits of Late Jurassic age, based mainly on the lacustrine ostracod fauna (although the top deposits may extend into the Early Cretaceous). These deposits comprise the so-called Afro-Brazilian Depression, initially characterized as containing the Brotas Group of the Recôncavo Basin (which includes the Aliança and the Sergi Formations) and subsequently extended into the Tucano, Jatobá, Camamu, Almada, Sergipe, Alagoas and Araripe Basins in northeastern Brazil, encompassing the study area of this paper. The large occurrence area of the Dom João Stage gives rise to discussions about the depositional connectivity between the basins, and the real extension of sedimentation. In the first studies of this stratigraphic interval, the Dom João Stage was strictly associated with the rift phase, as an initial stage (decades of 1960-70), but subsequent analyses considered the Dom João as an intracratonic basin or pre-rift phase - without any relation to the active mechanics of a tectonic syn-rift phase (decades of 1980-2000). The present work developed an evolutionary stratigraphic and tectonic model, based on the characterization of depositional sequences, internal flooding surfaces, depositional systems arrangement and paleoflow directions. Several outcrops on the onshore basins were used to build composite sections of each basin, comprising facies, architectural elements, depositional systems, stratigraphic and lithostratigraphic frameworks, and paleocurrents. In addition to that, over a hundred onshore and offshore exploration wells were used (only 21 of which are showed) to map the depositional sequences and generate correlation sections. These show the characteristics and relations of the Dom João Stage in each studied basin, and they were also extended to the Gabon Basin. The results indicate that there were two main phases during the Dom João Stage, in which distinctive sedimentary environments were developed, reflecting depositional system arrangements, paleoflow directions were diverse, and continuous or compartmented basins were developed.
Intrinsic evolution of novel (Nd, MM)2Fe14B-system magnetic flakes
NASA Astrophysics Data System (ADS)
Yu, Xiaoqiang; Zhu, Minggang; Liu, Weiqiang; Li, Yanfeng; Zhang, Jiuxing; Yue, Ming; Li, Wei
2018-01-01
The Nd-substituted (Nd x MM1- x )-Fe-B strip-casting flakes were prepared by induction melting in the vacuum furnace and then subsequently by strip-casting technology. The microstructure and magnetic properties of (Nd x MM1- x )-Fe-B alloys are related to the Nd substitution. 2:14:1 main phases and minor impure phases coexist in the MM-Fe-B flake. For example, La2O3 and CeFe2 impure phases are obviously detected in the x = 0 specimen. As an increase of the Ce concentration is inversely accompanied with the decrease of the Nd content ( x) in (Nd x MM1- x )2Fe14B main phases (0 ≤ x ≤ 1), XRD analysis shows that the overall diffraction peaks of the main phases shift to right domestically because of smaller radius Ce4+. The melting point, spin reorientation phase transition temperature, Curie temperature, magneto-crystalline anisotropy field (at 300 K), and the magnetization ( M 9T) for MM-Fe-B/(Nd0.4MM0.6)-Fe-B/(Nd0.7MM0.3)-Fe-B/Nd-Fe-B strip-casting alloys are 1376.15/1414.15/1439.15/1458.15 K, 74/113/124/135 K, 493.2/538.4/559.7/582.3 K, 48/55.2/64.4/70.1 kOe and 136.5/143.7/151.5/153.7 emu/g, respectively. Due to the varied composition of hard magnetic main phases, M 9T increases gradually with the increase of Nd content ( x). SEM observation and EDX results demonstrate that more Nd and Pr elements aggregate into the 2:14:1 ferromagnetic phase, while less La and Ce elements are prone to the RE-rich region compared with the nominal ratio. As a result, the growth of M 9T becomes extraordinary under maximum external field 9 T, indicating that the (Nd0.7MM0.3)-Fe-B flake may display relatively good magnetic properties and those with higher Nd content have evident effect on magnetization, compositions, and microstructures of hard magnetic main phases. Therefore, practical application of (Nd x MM1- x )-Fe-B-sintered magnets will be very prospective.
Tectonics and hydrocarbon potential of the Barents Megatrough
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baturin, D.; Vinogradov, A.; Yunov, A.
1991-08-01
Interpretation of geophysical data shows that the geological structure of the Eastern Barents Shelf, named Barents Megatrough (BM), extends sublongitudinally almost from the Baltic shield to the Franz Josef Land archipelago. The earth crust within the axis part of the BM is attenuated up to 28-30 km, whereas in adjacent areas its thickness exceeds 35 km. The depression is filled with of more than 15 km of Upper Paleozoic, Mesozoic, and Cenozoic sediments overlying a folded basement of probable Caledonian age. Paleozoic sediments, with exception of the Upper Permian, are composed mainly of carbonates and evaporites. Mesozoic-Cenozoic sediments are mostlymore » terrigenous. The major force in the development of the BM was due to extensional tectonics. Three rifting phases are recognizable: Late Devonian-Early Carboniferous, Early Triassic, and Jurassic-Early Cretaceous. The principal features of the geologic structure and evolution of the BM during the late Paleozoic-Mesozoic correlate well with those of the Sverdup basin, Canadian Arctic. Significant quantity of Late Jurassic-Early Cretaceous basaltic dikes and sills were intruded within Triassic sequence during the third rifting phase. This was probably the main reason for trap disruption and hydrocarbon loss from Triassic structures. Lower Jurassic and Lower Cretaceous reservoir sandstones are most probably the main future objects for oil and gas discoveries within the BM. Upper Jurassic black shales are probably the main source rocks of the BM basin, as well as excellent structural traps for hydrocarbon fluids from the underlying sediments.« less
Multicaloric effect in bi-layer multiferroic composites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vopson, M. M., E-mail: melvin.vopson@port.ac.uk; Zhou, D.; Caruntu, G.
2015-11-02
The multicaloric effect was theoretically proposed in 2012 and, despite numerous follow up studies, the effect still awaits experimental confirmation. The main limitation is the fact that the multicaloric effect is only observed at a temperature equal to the transition temperature of the magnetic and electric phases coexisting within a multiferroic (MF) (i.e., T ≈ T{sub c}{sup m} ≈ T{sub c}{sup e}). Such condition is hard to fulfill in single phase MFs and a solution is to develop suitable composite MF materials. Here, we examine the multicaloric effect in a bi-layer laminated composite MF in order to determine the optimal design parameters for bestmore » caloric response. We show that magnetically induced multicaloric effect requires magnetic component of heat capacity smaller than that of the electric phase, while the layer thickness of the magnetic phase must be at least 5 times the thickness of the electric phase. The electrically induced multicaloric effect requires the magnetic layer to be 10% of the electric phase thickness, while its heat capacity must be larger than that of the electric phase. These selection rules are generally applicable to bulk as well as thin film MF composites for optimal multicaloric effect.« less
Rotor performance characteristics from an aeroacoustic helicopter wind-tunnel test program
NASA Technical Reports Server (NTRS)
Hoad, D. R.; Elliott, J. W.; Orie, N. M.
1986-01-01
An investigation of helicopter rotor noise at model scale was conducted in the Langley 4 by 7 meter tunnel. The program described was the first of a planned three-phase project whose purpose was to examine the characteristic noise mechanism involved in main rotor/tail rotor interaction noise. This first phase was conducted with a main rotor only, in order to identify the characteristic noise generated by only the main rotor. The aerodynamic operating conditions of the rotor system were defined during the test. The acoustic data were properly referenced.
Single phase two pole/six pole motor
Kirschbaum, Herbert S.
1984-01-01
A single phase alternating current two pole/six pole motor is provided with a main stator winding having six coils disposed unequally around the periphery of the machine. These coils are divided into two groups. When these groups are connected such that their magnetomotive forces are additive, two pole motor operation results. When the polarity of one of the groups is then reversed, six pole motor operation results. An auxiliary stator winding which is similar to the main stator winding is displaced from the main stator winding by 90 electrical degrees on a two pole basis.
1979-04-01
programs for non-Federal dams. (3) To update, verify and complete the National Inventory of Dams. 1.2 DESCRIPTION OF PROJECT a. Location. The Lovejoy Pond...BUREAU OF STANDARDS- 1963-A 41 ANDROSCOGGIN RIVER BASIN NORTH WAYNE ,MAINE LOVEJOY POND DAM ME-00022 0 PHASE I INSPECTION REPORT NATIONAL DAM INSPECTION...side of necessar mnd idenifIr bioc Sigmmber) DAMS, INSPECTION, DAM SAFETY, * Androscoggin River Basin North Wayne, Maine Lovejoy Pond * 20. ABSTRACT
NASA Astrophysics Data System (ADS)
He, Yuchen; Satoshi, Uehara; Hidemasa, Takana; Hideya, Nishiyama
2016-09-01
A zero-dimensional model to simulate a nano-pulse-discharged bubble in water was developed. The model consists of gas and liquid phases corresponding to the inside and outside of the bubble, respectively. The diffusions of chemical species from the gas to the liquid phase through the bubble interface was also investigated. The initial gas is Ar, but includes a little H2O and O2 in the bubble. The time evolution of the OH concentration in the liquid phase was mainly investigated as an important species for water treatment. It was shown that OH was generated in the bubble and then diffused into the liquid. With the application of a continuous nano-pulse discharge, more OH radicals were generated as the frequency increased at a low voltage for a given power consumption. supported partially by Japan Society for the Promotion of Science (JSPS) KAKENHI (No. 26249015)
NASA Astrophysics Data System (ADS)
Szplet, R.; Kalisz, J.; Jachna, Z.
2009-02-01
We present a time digitizer having 45 ps resolution, integrated in a field programmable gate array (FPGA) device. The time interval measurement is based on the two-stage interpolation method. A dual-edge two-phase interpolator is driven by the on-chip synthesized 250 MHz clock with precise phase adjustment. An improved dual-edge double synchronizer was developed to control the main counter. The nonlinearity of the digitizer's transfer characteristic is identified and utilized by the dedicated hardware code processor for the on-the-fly correction of the output data. Application of presented ideas has resulted in the measurement uncertainty of the digitizer below 70 ps RMS over the time interval ranging from 0 to 1 s. The use of the two-stage interpolation and a fast FIFO memory has allowed us to obtain the maximum measurement rate of five million measurements per second.
Optical path design of phase contrast imaging on HL-2A tokamak
NASA Astrophysics Data System (ADS)
Qiyun, CHENG; Yi, YU; Shaobo, GONG; Min, XU; Tao, LAN; Wei, JIANG; Boda, YUAN; Yifan, WU; Lin, NIE; Rui, KE; Ting, LONG; Dong, GUO; Minyou, YE; Xuru, DUAN
2017-12-01
A phase contrast imaging (PCI) diagnostic has recently been developed on HL-2A tokamak. It can diagnose plasma density fluctuations with maximum wave number of 15 cm-1 and wave number resolution of 2 cm-1. The time resolution reaches 2 μs. A 10.6 μm CO2 laser is expanded to a beam with a diameter of 30 mm and injected into the plasma as an incident beam, injecting into plasma. The emerging scattered and unscattered beams are contrasted by a phase plate. The ideas of optical path design are presented in this paper, together with the parameters of the main optical components. The whole optical path of PCI is not only carefully designed, but also constructed on HL-2A. First calibration results show the ability of this system to catch plasma turbulence in a wide frequency domain.
Langley's CSI evolutionary model: Phase 2
NASA Technical Reports Server (NTRS)
Horta, Lucas G.; Reaves, Mercedes C.; Elliott, Kenny B.; Belvin, W. Keith; Teter, John E.
1995-01-01
Phase 2 testbed is part of a sequence of laboratory models, developed at NASA Langley Research Center, to enhance our understanding on how to model, control, and design structures for space applications. A key problem with structures that must perform in space is the appearance of unwanted vibrations during operations. Instruments, design independently by different scientists, must share the same vehicle causing them to interact with each other. Once in space, these problems are difficult to correct and therefore, prediction via analysis design, and experiments is very important. Phase 2 laboratory model and its predecessors are designed to fill a gap between theory and practice and to aid in understanding important aspects in modeling, sensor and actuator technology, ground testing techniques, and control design issues. This document provides detailed information on the truss structure and its main components, control computer architecture, and structural models generated along with corresponding experimental results.
Hydroxyapatite: Vibrational spectra and monoclinic to hexagonal phase transition
NASA Astrophysics Data System (ADS)
Slepko, Alexander; Demkov, Alexander A.
2015-02-01
Fundamental studies of biomaterials are necessary to deepen our understanding of their degradation and to develop cure for related illnesses. Biomineral hydroxyapatite Ca10(PO4)6(OH)2 is the main mineral constituent of mammal bone, and its synthetic analogues are used in biomedical applications. The mineral can be found in either hexagonal or monoclinic form. The transformation between these two phases is poorly understood, but knowing its mechanism may be critical to reversing processes in bone related to aging. Using density functional theory, we investigate the mechanisms of the phase transformation and estimate the transition temperature to be 680 K in fair agreement with the experimental temperature of 470 K. We also report the heat capacity of hydroxyapatite and a peculiarity in its phonon dispersion that might allow for non-destructive measurements of the crystal composition with applications in preventive medical screening for bone mineral loss.
SPHERES: From Ground Development to Operations on ISS
NASA Technical Reports Server (NTRS)
Katterhagen, A.
2015-01-01
SPHERES (Synchronized Position Hold Engage and Reorient Experimental Satellites) is an internal International Space Station (ISS) Facility that supports multiple investigations for the development of multi-spacecraft and robotic control algorithms. The SPHERES Facility on ISS is managed and operated by the SPHERES National Lab Facility at NASA Ames Research Center (ARC) at Moffett Field California. The SPHERES Facility on ISS consists of three self-contained eight-inch diameter free-floating satellites which perform the various flight algorithms and serve as a platform to support the integration of experimental hardware. To help make science a reality on the ISS, the SPHERES ARC team supports a Guest Scientist Program (GSP). This program allows anyone with new science the possibility to interface with the SPHERES team and hardware. In addition to highlighting the available SPHERES hardware on ISS and on the ground, this presentation will also highlight ground support, facilities, and resources available to guest researchers. Investigations on the ISS evolve through four main phases: Strategic, Tactical, Operations, and Post Operations. The Strategic Phase encompasses early planning beginning with initial contact by the Principle Investigator (PI) and the SPHERES program who may work with the PI to assess what assistance the PI may need. Once the basic parameters are understood, the investigation moves to the Tactical Phase which involves more detailed planning, development, and testing. Depending on the nature of the investigation, the tactical phase may be split into the Lab Tactical Phase or the ISS Tactical Phase due to the difference in requirements for the two destinations. The Operations Phase is when the actual science is performed; this can be either in the lab, or on the ISS. The Post Operations Phase encompasses data analysis and distribution, and generation of summary status and reports. The SPHERES Operations and Engineering teams at ARC is composed of experts who can guide the Payload Developer (PD) and Principle Investigator (PI) in reaching critical milestones to make their science a reality using the SPHERES platform. From performing integrated safety and verification assessments, to assisting in developing crew procedures and operations products, to organizing, planning, and executing all test sessions, to helping manage data products, the SPHERES team at ARC is available to support microgravity research with the SPEHRES Guest Scientist Program.
Wick, Carson A.; McClellan, James H.; Arepalli, Chesnal D.; Auffermann, William F.; Henry, Travis S.; Khosa, Faisal; Coy, Adam M.; Tridandapani, Srini
2015-01-01
Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as well as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (PAGG) and IVS (PIV S) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (PCT). The one exception was the RCA, which improved for PAGG for 18 of the 20 subjects when compared to PCT (PCT = 2.48; PAGG = 2.07, p = 0.001). Conclusions: A method for quantifying the motion of specific coronary vessels using a correlation-based, phase-to-phase deviation measure was developed and tested on 20 patients receiving cardiac CT exams. The IVS was found to be a suitable predictor of vessel quiescence. The diagnostic quality of the quiescent phases detected by the proposed methods was comparable to those calculated by the CT scanner. The ability to quantify coronary vessel quiescence from the motion of the IVS can be used to develop new CTCA gating techniques and quantify the resulting potential improvement in CTCA image quality. PMID:25652511
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wick, Carson A.; McClellan, James H.; Arepalli, Chesnal D.
2015-02-15
Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as wellmore » as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (P{sub AGG}) and IVS (P{sub IV} {sub S}) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (P{sub CT}). The one exception was the RCA, which improved for P{sub AGG} for 18 of the 20 subjects when compared to P{sub CT} (P{sub CT} = 2.48; P{sub AGG} = 2.07, p = 0.001). Conclusions: A method for quantifying the motion of specific coronary vessels using a correlation-based, phase-to-phase deviation measure was developed and tested on 20 patients receiving cardiac CT exams. The IVS was found to be a suitable predictor of vessel quiescence. The diagnostic quality of the quiescent phases detected by the proposed methods was comparable to those calculated by the CT scanner. The ability to quantify coronary vessel quiescence from the motion of the IVS can be used to develop new CTCA gating techniques and quantify the resulting potential improvement in CTCA image quality.« less
NASA Astrophysics Data System (ADS)
Shi, Xue-Feng; Wang, Hai-Chen; Tang, Ping-Ying; Tang, Bi-Yu
2017-09-01
To predict and compare the main reinforcement effects of the key precipitation phases Mg2Cu3Si, Mg2Si and MgCu2 in Mg-Cu-Si alloy, the structural, mechanical and electronic properties of these phases have been studied by ab initio calculations. The lowest formation enthalpy and cohesive energy indicate that Mg2Cu3Si has the strongest alloying ability and structural stability. The mechanical modulus indicates that Mg2Cu3Si has the strongest resistance to reversible shear/volume distortion and has maximum hardness. The characterization of brittle (ductile) behavior manifests that MgCu2 has favorable ductility. Meanwhile the evaluation of elastic anisotropy indicates that Mg2Si possesses elastic isotropy. Debye temperature prediction shows that Mg2Si and Mg2Cu3Si have better thermal stability. To achieve an unbiased interpretation on the phase stability and mechanical behavior of these precipitation phases, the density of states and differential charge densities are also analyzed. The current study deepens the comprehensive understanding of main reinforcement effects of these precipitation phases on Mg-Cu-Si alloys, and also benefits to optimize the overall performances of Mg-Cu-Si alloy from the hardness, ductility and thermal stability by controlling these second precipitation phases during the heat treatment process.
The Main Transport System in the Wheat Ear
NASA Technical Reports Server (NTRS)
Stieber, Joseph; Stieber, Joli; Bubenheim, David L.; Kliss, Mark (Technical Monitor)
1996-01-01
The vascular system in the rachis, rachilla, and florets of the wheat ear was studied by direct microscopical observation of cleaned semi longitudinal sections. A periodic repetitive change of amphivasal and collateral phases was found along each main vascular bundle in the rachis. This change alternates between the two groups of main bundles and is related to the bilateral alternate arrangement of the spikelets on the rachis, so that a large amphivasal phase of the one group opposes the collateral phase of the other group. Ring-shaped tracheary inter-connections were observed mostly at the nodes. A similar system was found in the rachilla. There is a continuous uninterrupted tracheary connection between each of the florets and the rachis. A functional significance of the periodic changes observed has been suggested.
Development and fabrication of structural components for a scramjet engine
NASA Technical Reports Server (NTRS)
Buchmann, O. A.
1990-01-01
A program broadly directed toward design and development of long-life (100 hours and 1,000 cycles with a goal of 1,000 hours and 10,000 cycles) hydrogen-cooled structures for application to scramjets is presented. Previous phases of the program resulted in an overall engine design and analytical and experimental characterization of selected candidate materials and concepts. The latter efforts indicated that the basic life goals for the program can be reached with available means. The main objective of this effort was an integrated, experimental evaluation of the results of the previous program phases. The fuel injection strut was selected for this purpose, including fabrication development and fabrication of a full-scale strut. Testing of the completed strut was to be performed in a NASA-Langley wind tunnel. In addition, conceptual designs were formulated for a heat transfer test unit and a flat panel structural test unit. Tooling and fabrication procedures required to fabricate the strut were developed, and fabrication and delivery to NASA of all strut components, including major subassemblies, were completed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Louge, M. Y.; Jenkins, J. T.
The main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. In particular, capacitance probes are designed to measure local, time-dependent particle concentrations. In addition, a new optical fiber probe based on laser-induced-phosphorescence is developed to measure particle velocities. The principles for the capacitance and optical diagnostics were given in our first and second quarterly reports. In this reporting period, we have demonstrated with success the feasibility of the optical fiber probe. Another objective of this work is to develop a model of dense-phase conveying and to test thismore » model in a setup that incorporates our diagnostics. In this period, as a prelude to these modeling efforts scheduled for the third year of the contract, we have carried out additional computer simulations of rapid granular flows to verify the theories of Jenkins and Richman (1988) on the anisotropy of the second moment in simple shear. 2 refs., 5 figs.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Kezhao; Ni, Longchang; Lei, Zhenglong, E-ma
The tensile deformation behavior of laser welded Ti{sub 2}AlNb joints was investigated using in situ analysis methods. The fracture mode of the single-B2-phase fusion zone was quasi-cleavage at room temperature and intergranular at 650 °C, while that of base metal was microvoid coalescence at both room temperature and 650 °C. Tensile deformation at room temperature was observed using in situ SEM tensile testing. In base metal, microcracks nucleated and propagated mainly within the O phase or along O/B2 phase boundaries. While both the cross- and multi-slips were found in the single-B2-phase fusion zone, a confocal laser scanning microscopy was usedmore » to observe the crack initiation and propagation process in situ at 650 °C. Cracks mainly formed along the B2/O phase boundaries in base metal, along the fragile grain boundaries of B2 phase in the fusion zone. The thermal simulation experiment and following TEM analysis indicated that the precipitation of continuous O-phase films along the B2 grain boundaries resulted in the high temperature brittleness of laser welded Ti{sub 2}AlNb joints. - Highlights: •Cracks formed within O phase or along B2/O boundaries in the base metal. •Cross- and multi-slips relieved stress in the fusion zone at room temperature. •Cracks mainly formed along the B2/O boundaries at 650 °C. •In the fusion zone, intergranular cracks were in situ observed at 650 °C. •O-phase films along B2 grain boundaries caused the high temperature brittleness.« less
Simulations of phase space distributions of storm time proton ring current
NASA Technical Reports Server (NTRS)
Chen, Margaret W.; Lyons, Larry R.; Schulz, Michael
1994-01-01
We use results of guiding-center simulations of ion transport to map phase space densities of the stormtime proton ring current. We model a storm as a sequence of substorm-associated enhancements in the convection electric field. Our pre-storm phase space distribution is an analytical solution to a steady-state transport model in which quiet-time radial diffusion balances charge exchange. This pre-storm phase space spectra at L approximately 2 to 4 reproduce many of the features found in observed quiet-time spectra. Using results from simulations of ion transport during model storms having main phases of 3, 6, and 12 hr, we map phase space distributions from the pre-storm distribution in accordance with Liouville's theorem. We find stormtime enhancements in the phase space densities at energies E approximately 30-160 keV for L approximately 2.5 to 4. These enhancements agree well with the observed stormtime ring current. For storms with shorter main phases (approximately 3 hr), the enhancements are caused mainly by the trapping of ions injected from open night side trajectories, and diffusive transport of higher-energy (greater than or approximately 160 keV) ions contributes little to the stormtime ring current. However, the stormtime ring current is augmented also by the diffusive transport of higher-energy ions (E greater than or approximately 160 keV) durinng stroms having longer main phases (greater than or approximately 6 hr). In order to account for the increase in Dst associated with the formation of the stormtime ring current, we estimate the enhancement in particle-energy content that results from stormtime ion transport in the equatorial magnetosphere. We find that transport alone cannot account for the entire increase in absolute value of Dst typical of a major storm. However, we can account for the entire increase in absolute value of Dst by realistically increasing the stormtime outer boundary value of the phase space density relative to the quiet-time value. We compute the magnetic field produced by the ring current itself and find that radial profiles of the magnetic field depression resemble those obtained from observational data.
Space Shuttle Main Engine (SSME) LOX turbopump pump-end bearing analysis
NASA Technical Reports Server (NTRS)
1986-01-01
A simulation of the shaft/bearing system of the Space Shuttle Main Engine Liquid Oxygen turbopump was developed. The simulation model allows the thermal and mechanical characteristics to interact as a realistic simulation of the bearing operating characteristics. The model accounts for single and two phase coolant conditions, and includes the heat generation from bearing friction and fluid stirring. Using the simulation model, parametric analyses were performed on the 45 mm pump-end bearings to investigate the sensitivity of bearing characteristics to contact friction, axial preload, coolant flow rate, coolant inlet temperature and quality, heat transfer coefficients, outer race clearance and misalignment, and the effects of thermally isolating the outer race from the isolator.
A unified classification of stationary phases for packed column supercritical fluid chromatography.
West, C; Lesellier, E
2008-05-16
The use of supercritical fluids as chromatographic mobile phases allows to obtain rapid separations with high efficiency on packed columns, which could favour the replacement of numerous HPLC methods by supercritical fluid chromatography (SFC) ones. Moreover, despite some unexpected chromatographic behaviours, general retention rules are now well understood, and mainly depend on the nature of the stationary phase. The use of polar stationary phases improves the retention of polar compounds, when C18-bonded silica favours the retention of hydrocarbonaceous compounds. In this sense, reversed-phase and normal-phase chromatography can be achieved in SFC, as in HPLC. However, these two domains are clearly separated in HPLC due to the opposite polarity of the mobile phases used for each method. In SFC, the same mobile phase can be used with both polar and non-polar stationary phases. Consequently, the need for a novel classification of stationary phases in SFC appears, allowing a unification of the classical reversed- and normal-phase domains. In this objective, the paper presents the development of a five-dimensional classification based on retention data for 94-111 solutes, using 28 commercially available columns representative of three major types of stationary phases. This classification diagram is based on a linear solvation energy relationship, on the use of solvation vectors and the calculation of similarity factors between the different chromatographic systems. This classification will be of great help in the choice of the well-suited stationary phase, either in regards of a particular separation or to improve the coupling of columns with complementary properties.
TOWARDS A NOVEL MODULAR ARCHITECTURE FOR CERN RADIATION MONITORING.
Boukabache, Hamza; Pangallo, Michel; Ducos, Gael; Cardines, Nicola; Bellotta, Antonio; Toner, Ciarán; Perrin, Daniel; Forkel-Wirth, Doris
2017-04-01
The European Organization for Nuclear Research (CERN) has the legal obligation to protect the public and the people working on its premises from any unjustified exposure to ionising radiation. In this context, radiation monitoring is one of the main concerns of the Radiation Protection Group. After 30 y of reliable service, the ARea CONtroller (ARCON) system is approaching the end of its lifecycle, which raises the need for new, more efficient radiation monitors with a high level of modularity to ensure better maintainability. Based on these two main principles, new detectors are currently being developed that will be capable of measuring very low dose rates down to 50 nSv h-1, whilst being able to measure radiation over an extensive range of 8 decades without any auto scaling. To reach these performances, CERN Radiation MOnitoring Electronics (CROME), the new generation of CERN radiation monitors, is based on the versatile architecture that includes new read-out electronics developed by the Instrumentation and Logistics section of the CERN Radiation Protection Group as well as a reconfigurable system on chip capable of performing complex processing calculations. Beside the capabilities of CROME to continuously measure the ambient dose rate, the system generates radiation alarms, provides interlock signals, drives alarm display units through a fieldbus and provides long-term, permanent and reliable data logging. The measurement tests performed during the first phase of the development show very promising results that pave the way to the second phase: the certification. © The Author 2016. Published by Oxford University Press.
TOWARDS A NOVEL MODULAR ARCHITECTURE FOR CERN RADIATION MONITORING
Boukabache, Hamza; Pangallo, Michel; Ducos, Gael; Cardines, Nicola; Bellotta, Antonio; Toner, Ciarán; Perrin, Daniel; Forkel-Wirth, Doris
2017-01-01
Abstract The European Organization for Nuclear Research (CERN) has the legal obligation to protect the public and the people working on its premises from any unjustified exposure to ionising radiation. In this context, radiation monitoring is one of the main concerns of the Radiation Protection Group. After 30 y of reliable service, the ARea CONtroller (ARCON) system is approaching the end of its lifecycle, which raises the need for new, more efficient radiation monitors with a high level of modularity to ensure better maintainability. Based on these two main principles, new detectors are currently being developed that will be capable of measuring very low dose rates down to 50 nSv h−1, whilst being able to measure radiation over an extensive range of 8 decades without any auto scaling. To reach these performances, CERN Radiation MOnitoring Electronics (CROME), the new generation of CERN radiation monitors, is based on the versatile architecture that includes new read-out electronics developed by the Instrumentation and Logistics section of the CERN Radiation Protection Group as well as a reconfigurable system on chip capable of performing complex processing calculations. Beside the capabilities of CROME to continuously measure the ambient dose rate, the system generates radiation alarms, provides interlock signals, drives alarm display units through a fieldbus and provides long-term, permanent and reliable data logging. The measurement tests performed during the first phase of the development show very promising results that pave the way to the second phase: the certification. PMID:27909154
Gritsun, Taras A; le Feber, Joost; Rutten, Wim L C
2012-01-01
A typical property of isolated cultured neuronal networks of dissociated rat cortical cells is synchronized spiking, called bursting, starting about one week after plating, when the dissociated cells have sufficiently sent out their neurites and formed enough synaptic connections. This paper is the third in a series of three on simulation models of cultured networks. Our two previous studies [26], [27] have shown that random recurrent network activity models generate intra- and inter-bursting patterns similar to experimental data. The networks were noise or pacemaker-driven and had Izhikevich-neuronal elements with only short-term plastic (STP) synapses (so, no long-term potentiation, LTP, or depression, LTD, was included). However, elevated pre-phases (burst leaders) and after-phases of burst main shapes, that usually arise during the development of the network, were not yet simulated in sufficient detail. This lack of detail may be due to the fact that the random models completely missed network topology .and a growth model. Therefore, the present paper adds, for the first time, a growth model to the activity model, to give the network a time dependent topology and to explain burst shapes in more detail. Again, without LTP or LTD mechanisms. The integrated growth-activity model yielded realistic bursting patterns. The automatic adjustment of various mutually interdependent network parameters is one of the major advantages of our current approach. Spatio-temporal bursting activity was validated against experiment. Depending on network size, wave reverberation mechanisms were seen along the network boundaries, which may explain the generation of phases of elevated firing before and after the main phase of the burst shape.In summary, the results show that adding topology and growth explain burst shapes in great detail and suggest that young networks still lack/do not need LTP or LTD mechanisms.
Mining The Sdss-moc Database For Main-belt Asteroid Solar Phase Behavior.
NASA Astrophysics Data System (ADS)
Truong, Thien-Tin; Hicks, M. D.
2010-10-01
The 4th Release of the Sloan Digital Sky Survey Moving Object Catalog (SDSS-MOC) contains 471569 moving object detections from 519 observing runs obtained up to March 2007. Of these, 220101 observations were linked with 104449 known small bodies, with 2150 asteroids sampled at least 10 times. It is our goal to mine this database in order to extract solar phase curve information for a large number of main-belt asteroids of different dynamical and taxonomic classes. We found that a simple linear phase curve fit allowed us to reject data contaminated by intrinsic rotational lightcurves and other effects. As expected, a running mean of solar phase coefficient is strongly correlated with orbital elements, with the inner main-belt dominated by bright S-type asteroids and transitioning to darker C and D-type asteroids with steeper solar phase slopes. We shall fit the empirical H-G model to our 2150 multi-sampled asteroids and correlate these parameters with spectral type derived from the SDSS colors and position within the asteroid belt. Our data should also allow us to constrain solar phase reddening for a variety of taxonomic classes. We shall discuss errors induced by the standard "g=0.15" assumption made in absolute magnitude determination, which may slightly affect number-size distribution models.
Recovery Act - Refinement of Cross Flow Turbine Airfoils
DOE Office of Scientific and Technical Information (OSTI.GOV)
McEntee, Jarlath
2013-08-30
Ocean Renewable Power Company, LLC (ORPC) is a global leader in hydrokinetic technology and project development. ORPC develops hydrokinetic power systems and eco-conscious projects that harness the power of oceans and rivers to create clean, predictable renewable energy. ORPC’s technology consists of a family of modular hydrokinetic power systems: the TidGen® Power System, for use at shallow to medium-depth tidal sites; the RivGen™ Power System, for use at river and estuary sites; and the OCGen® Power System, presently under development, for use at deep tidal and offshore ocean current sites. These power systems convert kinetic energy in moving water intomore » clean, renewable, grid-compatible electric power. The core technology component for all ORPC power systems is its patented turbine generator unit (TGU). The TGU uses proprietary advanced design cross flow (ADCF) turbines to drive an underwater permanent magnet generator mounted at the TGU’s center. It is a gearless, direct-drive system that has the potential for high reliability, requires no lubricants and releases no toxins that could contaminate the surrounding water. The hydrokinetic industry shows tremendous promise as a means of helping reduce the U.S.’s use of fossil fuels and dependence on foreign oil. To exploit this market opportunity, cross-flow hydrokinetic devices need to advance beyond the pre-commercial state and more systematic data about the structure and function of cross-flow hydrokinetic devices is required. This DOE STTR project, “Recovery Act - Refinement of Cross Flow Turbine Airfoils,” refined the cross-flow turbine design process to improve efficiency and performance and developed turbine manufacturing processes appropriate for volume production. The project proposed (1) to overcome the lack of data by extensively studying the properties of cross flow turbines, a particularly competitive design approach for extracting hydrokinetic energy and (2) to help ORPC mature its pre-commercial hydrokinetic technology into a commercially viable product over a three-year period by means of a design-for-manufacture process to be applied to the turbines which would result in a detail turbine design suitable for volume manufacture. In Phase I of the Project, ORPC systematically investigated performance of cross flow turbines by varying design parameters including solidity, foil profile, number of foils and foil toe angle using scale models of ORPC’s turbine design in a tow tank at the University of Maine (UMaine). Data collected provided information on interactions between design variables and helped ORPC improve turbine efficiency from 21% to greater than 35%. Analytical models were developed to better understand the physical phenomena at play in cross-flow turbines. In Phase II of the Project, ORPC expanded on data collected in Phase I to continue improving turbine efficiency, with a goal to optimally approach the Betz limit of 59.3%. Further tow tank testing and development of the analytical models and techniques was completed at UMaine and led to a deeper understanding of the flow phenomena involved. In addition, ORPC evaluated various designs, materials and manufacturing methods for full-scale turbine foils, and identified those most conducive to volume manufacture. Selected components of the turbine were structurally tested in a laboratory environment at UMaine. Performance and structural testing of the full scale turbine design was conducted as part of the field testing. The work funded by this project enabled the development of design tools for the rapid and efficient development of high performance cross-flow hydrokinetic turbine foils. The analytical tools are accurate and properly capture the underlying physical flow phenomena present in hydrokinetic cross-flow turbines. The ability to efficiently examine the design space provides substantial economic benefit to ORPC in that it allows for rapid design iteration at a low computational cost. The design-for-manufacture work enabled the delivery of a turbine design suitable for manufacture in intermediate to large quantity, lowering the unit cost of turbines and the levelized cost of electricity from ORPC hydrokinetic turbine. ORPC fielded the turbine design in a full scale application – the Cobscook Bay Tidal Energy Project which began operation off the coast of Eastport, Maine in September 2012. This is the first commercial, grid-connected tidal energy project in North America and the only ocean energy project not involving a dam which delivers power to a utility grid anywhere in the Americas. ORPC received a Federal Energy Regulatory Commission pilot project license to install and operate this project in February 2012. Construction of the TidGen® Power System began in March 2012, and the system was grid-connected on September 13, 2012. A 20-year commercial power purchase agreement to sell the power generated by the project was completed with Bangor Hydro Electric Company and is the first and only power purchase agreement for tidal energy. This is the first project in the U.S. to receive Renewable Energy Certificates for tidal energy production. The STTR project is a benefit to the public through its creation of jobs. ORPC’s recent deployment of the TidGen™ Power System is part of their larger project, the Maine Tidal Energy Project. According to ORPC’s report to the Maine Public Utilities Commission and the 20-year power purchase agreement, the Maine Tidal Energy Project will create and/or retain at least 80 direct full-time equivalent jobs in Maine during the development, construction and installation phase (2011 through 2016). In addition, the Maine Tidal Energy Project will create and/or retain at least 12 direct full-time equivalent jobs in Maine during the operating and maintenance phase (2016 through 2020). The STTR project has facilitated new and expanded services in manufacturing, fabrication and assembly, including major business growth for the composite technologies sector; creation of deepwater deployment, maintenance and retrieval services; and the expansion and formation of technical support services such as site assessment and design services, geotechnical services, underwater transmission services, and environmental monitoring services. The Maine Tidal Energy Project’s impact on workforce will enable other ocean energy projects – be they offshore wind, wave or additional tidal opportunities – to succeed in Maine. ORPC received a 2013 Tibbetts Award by the U.S. Small Business Administration.« less
Multiwavelength Diagnostics of the Precursor and Main Phases of an M1.8 Flare on 2011 April 22
NASA Technical Reports Server (NTRS)
Awasthi, A. K.; Jain, R.; Gadhiya, P. D.; Aschwanden, M. J.; Uddin, W.; Srivastava, A. K.; Chandra, R.; Gopalswamy, N.; Nitta, N. V.; Yashiro, S.;
2013-01-01
We study the temporal, spatial and spectral evolution of the M1.8 flare, which occurred in the active region 11195 (S17E31) on 2011 April 22, and explore the underlying physical processes during the precursor phase and their relation to the main phase. The study of the source morphology using the composite images in 131Å wavelength observed by the Solar Dynamics Observatory/Atmospheric Imaging Assembly and 6-14 kiloelectronvolts [from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI)] revealed a multi-loop system that destabilized systematically during the precursor and main phases. In contrast, hard X-ray emission (20-50 kiloelectronvolts) was absent during the precursor phase, appearing only from the onset of the impulsive phase in the form of foot-points of emitting loops. This study also revealed the heated loop-top prior to the loop emission, although no accompanying foot-point sources were observed during the precursor phase. We estimate the flare plasma parameters, namely temperature (T), emission measure (EM), power-law index (gamma) and photon turn-over energy (to), and found them to be varying in the ranges 12.4-23.4 megakelvins, 0.0003-0.6 x 10 (sup 49) per cubic centimeter, 5-9 and 14-18 kiloelectronvolts, respectively, by forward fitting RHESSI spectral observations. The energy released in the precursor phase was thermal and constituted approximately 1 percent of the total energy released during the flare. The study of morphological evolution of the filament in conjunction with synthesized T and EM maps was carried out, which reveals (a) partial filament eruption prior to the onset of the precursor emission and (b) heated dense plasma over the polarity inversion line and in the vicinity of the slowly rising filament during the precursor phase. Based on the implications from multiwavelength observations, we propose a scheme to unify the energy release during the precursor and main phase emissions in which the precursor phase emission was originated via conduction front that resulted due to the partial filament eruption. Next, the heated leftover S-shaped filament underwent slow-rise and heating due to magnetic reconnection and finally erupted to produce emission during the impulsive and gradual phases.
Awofisayo, A; Ibbotson, S; Smith, G E; Janmohamed, K; Mohamed, H; Olowokure, B
2013-07-01
School closure as a social distancing measure was used in some countries during the initial phases of the influenza A(H1N1)pdm09 pandemic. The objective of this paper is to describe the use of a risk-based approach to public health interventions for schools during the 'containment phase' of the pandemic and to describe lessons learnt. The development of a framework for risk assessment and decision-making to determine school closures in the West Midlands, England, during the 'containment phase' of influenza A(H1N1)pdm09 pandemic is described. Using the framework developed during the 'containment phase', assessments were conducted for 344 educational institutions who reported confirmed cases or 'particularly high absenteeism'. Of these, 209 (60%) had confirmed cases and 65 were closed, mainly for public health or operational reasons. Schools were closed on an individual basis, during the most intense period of the pandemic and for an average period of six days (maximum 11 days). The risk-based approach evolved as experience and knowledge of influenza A(H1N1)pdm09 pandemic virus increased, however some decisions were difficult to communicate to parents, schools and stakeholders particularly when the number of schools affected escalated and the pandemic response phases changed. The management of school closures is an 'uncertain art'. Numerous challenges and lessons were identified in attempting, during the containment phase of the influenza A(H1N1)pdm09 pandemic, to ensure consistency and transparency in an increasingly complex process. The overall approach described could be further developed to improve decision-making for infectious diseases in schools. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Lukolo, Linda Ndeshipandula; van Dyk, Agnes
2015-01-01
Talking about sexuality has never been easy in most Namibians cultures and it seems that most parents feel uncomfortable and embarrassed to talk openly with their children about sexuality. They do not participate in the sexuality education of their children, because they believe they are unable to provide quality and adequate sexuality information due to their lack of knowledge about human sexuality or their perceived inability to explain what they do know. The ultimate purpose of this study was to develop, describe, implement and evaluate an educational programme to empower rural parents to participate in the sexuality education of their children. The study was designed to be qualitative, explorative, descriptive and contextual in nature. It was performed in three phases. Phase 1 consisted of a situational analysis to explore and describe how parents provide sexuality education. Phase 2 consisted of the development of a conceptual framework that facilitated the development of an educational programme. In phase 3 the programme was implemented and evaluated, recommendations were made and conclusions drawn. The main findings revealed two themes: factors influencing parental participation in their children’s sexuality education, and the need for parental participation in their children’s sexuality education. This article is part of series of three article stems from a study on the topic of sexuality education empowerment programme of rural parents in Namibia. The three articles have the following titles: one: parent’s participation in sexuality education of their children: a situational analysis; two: conceptual framework developments that facilitate the development of an educational programme and three: programme implementation and evaluation. This article dealt with parent’s participation in sexuality education of their children: a situational analysis. PMID:25560329
Vandermosten, Leen; Pham, Thao-Thy; Possemiers, Hendrik; Knoops, Sofie; Van Herck, Evelien; Deckers, Julie; Franke-Fayard, Blandine; Lamb, Tracey J; Janse, Chris J; Opdenakker, Ghislain; Van den Steen, Philippe E
2018-03-05
Malaria-associated acute respiratory distress syndrome (MA-ARDS) is a complication of malaria with a lethality rate of up to 80% despite anti-malarial treatment. It is characterized by a vast infiltration of leukocytes, microhaemorrhages and vasogenic oedema in the lungs. Previously, a mouse model for MA-ARDS was developed by infection of C57BL/6 mice with the Edinburgh line NK65-E of Plasmodium berghei. Here, both host and parasite factors were demonstrated to play crucial roles in the development and severity of lung pathology. In particular, the genetic constitution of the host was an important determinant in the development of MA-ARDS. Both male and female C57BL/6, but not BALB/c, mice developed MA-ARDS when infected with P. berghei NK65-E. However, the New York line of P. berghei NK65 (NK65-NY) did not induce demonstrable MA-ARDS, despite its accumulation in the lungs and fat tissue to a similar or even higher extent as P. berghei NK65-E. These two commonly used lines of P. berghei differ in their red blood cell preference. P. berghei NK65-NY showed a stronger predilection for reticulocytes than P. berghei NK65-E and this appeared to be associated with a lower pathogenicity in the lungs. The pulmonary pathology in the C57BL/6/P. berghei NK65-E model was more pronounced than in the model with infection of DBA/2 mice with P. berghei strain ANKA. The transient lung pathology in DBA/2 mice infected with P. berghei ANKA coincided with the infection phase in which parasites mainly infected normocytes. This phase was followed by a less pathogenic phase in which P. berghei ANKA mainly infected reticulocytes. The propensity of mice to develop MA-ARDS during P. berghei infection depends on both host and parasite factors and appears to correlate with RBC preference. These data provide insights in induction of MA-ARDS and may guide the choice of different mouse-parasite combinations to study lung pathology.
ERIC Educational Resources Information Center
Lee, Kyungmee; Brett, Clare
2013-01-01
This qualitative case study is the first phase of a large-scale design-based research project to implement a theoretically derived double-layered CoP model within real-world teacher development practices. The main goal of this first iteration is to evaluate the courses and test and refine the CoP model for future implementations. This paper…
Marsella, L T; Savastano, L; Saracino, V; Del Vecchio, R
2005-01-01
The authors emphasize the violation of children's and adolescents' rights as a result of the exploitation of child labour. Besides the legal aspect, they pointed out the medical features related to the delicate growing process of the child in the phases of development and adaptation of the main organs to hard work. Currently the problem is being supervised by those states that recognize the right for minors to be protected against any kind of physical, mental, spiritual and moral risk.
Chemical modification of electrolytes for lithium batteries
NASA Astrophysics Data System (ADS)
Afanas'ev, Vladimir N.; Grechin, Aleksandr G.
2002-09-01
Modern approaches to modifying chemically electrolytes for lithium batteries are analysed with the aim of optimising the charge-transfer processes in liquid-phase and solid (polymeric) media. The main regularities of transport properties of lithium electrolyte solutions containing complex (encapsulated) ions in aprotic solvents and polymers are discussed. The prospects for the development of electrolytic solvosystems with the chain (ionotropic) mechanism of conduction with respect to lithium ions are outlined. The bibliography includes 126 references.
Problems and perspectives in paraplegia
NASA Technical Reports Server (NTRS)
Nashold, B.
1974-01-01
Improved clinical treatment of the paraplegic, developed during World War II, has reduced the overall mortality rate from close to 100 percent to 30 percent. Despite major clinical improvements, mainly in treatment of the acute phase of paraplegia, and despite greater rehabilitation efforts, the spinal injured person is never rehabilitated in the sense that he reaches an optimum and stays there. He is always exposed to the constant threat of deterioration of his physiological, sociological, and psychological state.
Hypersonic Experimental and Computational Capability, Improvement and Validation. Volume 2
NASA Technical Reports Server (NTRS)
Muylaert, Jean (Editor); Kumar, Ajay (Editor); Dujarric, Christian (Editor)
1998-01-01
The results of the phase 2 effort conducted under AGARD Working Group 18 on Hypersonic Experimental and Computational Capability, Improvement and Validation are presented in this report. The first volume, published in May 1996, mainly focused on the design methodology, plans and some initial results of experiments that had been conducted to serve as validation benchmarks. The current volume presents the detailed experimental and computational data base developed during this effort.
[Tuberculosis and its control--lessons from the past and future prospect].
Shimao, Tadao
2005-06-01
Koch R reported the discovery of tubercle bacilli on March 24, 1882, and the numbers of death from phthisis were collected in the vital statistics from the latter half of 1883 in Japan. Tuberculosis death was officially adopted in the Japanese vital statistics from 1899, and there was certain disagreement existed between the numbers of death from TB and phthisis in 1899, the analysis on the trend of TB in Japan was done based on TB death. Trend of TB in Japan in the past 100 years could be divided into five phases. In phase 1 (1899-1918), TB mortality had increased with the first industrialization of Japan with main focus on the weaving industry. During this period, TB mortality of female was higher than that of male and then major victims of TB were young girls born from 1890 to 1925. In phase 2 (1918-1930), TB mortality decreased through excess death of TB cases by the influenza pandemic in 1918. This decline due to influenza pandemic was seen all over the world, and in the European countries and the U.S., the decline continued up to 1945 while in Japan, TB had increased again in the phase 3 (1930-1945) mainly due to second industrialization with main focus on heavy industry and the impact of quasi-war and war conditions. In phase 4 (1945-mid 1970s), TB started to decline fast due to the excess death of TB cases during the World War II and then, the application of modern TB control started from early 1950s. In phase 5 (from mid 1970s until now), decline of TB has showed down. Increase or slowdown of TB decline was seen nearly all countries of the world, however, its causes were different from country to country. In case of Japan, slowdown was caused by the rapid ageing of the population, in developing countries mainly by the impact of HIV epidemic and in industrialized countries, mainly by the migration of the population and partly by the HIV epidemic. Contribution of phthisiology in Japan to the global progress of phthisiology could be summarized as follows: elucidation of the pathogenesis of TB when TB was highly prevalent in Japan by high incidence of TB from primarily infected youth, the development of mass screening for TB using radiophotography technique developed in Japan, completion of the interpretation method of chest X-ray findings, first success in the mass production of freeze-dried BCG vaccine in the world, the first implementation of the TB prevalence survey using random sampling method in 1953, and the development of a new drug for TB, kanamycin. Phthisiology also contributed to the progress of international health. As the objective index to measure the magnitude of TB problem, the concept of annual risk of TB infection (ARTI) was introduced by Sutherland and Styblo, and by using ARTI, the epidemiological situation of TB could be divided into 3 categories; high prevalence country with ARTI above 1%, low prevalence country below 0.05-0.1%, and middle prevalence country inbetween. To reduce the burden of TB in high prevalence countries, so-called DOTS strategy of TB control was introduced and has been applied in most developing countries, and the gap between high and low prevalence countries has reduced in the past decade. Cooperation in global TB control has also been done actively from the government and NGOs of industrialized countries under the strong leadership of WHO. For the success of TB control, the transmission of tubercle bacilli in a community should be cut either infection, onset of TB or the progress of TB. Prevention of TB infection could be achieved by the early detection of TB cases and their cure by the treatment. To encourage early visit to doctors for those with symptoms suggesting TB and adequate examinations at medical institutions for these persons would be a major tool of early detection of TB cases in Japan in the future. In addition, there is no doubt to intensify contacts examinations and source investigations. It is hoped to elucidate recent pathogenesis of TB by applying new technologies such as QFT and RFLP. Prevention of onset of TB will be focused on the preventive use of TB drugs, however, development of new vaccine better than BCG is also encouraged for the developing countries where the risk of TB infection is remained high. TB is now a curable disease, and the duration of treatment has been shortened to 6 months. If new more potent TB drugs were developed, and the total duration of treatment could be shortened, the global TB control could be done much more easily, and also most MDRTB cases could be cured. Otsuka Pharmaceutical Company is now developing a new potent drug which has no cross resistance with existing TB drugs. This new drug is now on the clinical trial phase II, and it is hoped that Japan can make another great contribution to the global TB control. It is my sincere wish that the government continues to assist the research to develop new TB drugs and new technologies used in TB control, and in future, if it is needed to change the current policy of TB control, a new policy should be tried in a pilot area before its introduction on national level. The Japanese Society for TB is a key organization in developing further research and the training of new personnel engaging in TB research and control, and I sincerely hope further development of the Society.
A Smart Wearable Sensor System for Counter-Fighting Overweight in Teenagers.
Standoli, Carlo Emilio; Guarneri, Maria Renata; Perego, Paolo; Mazzola, Marco; Mazzola, Alessandra; Andreoni, Giuseppe
2016-08-10
PEGASO is a FP7-funded project whose goal is to develop an ICT and mobile-based platform together with an appropriate strategy to tackle the diffusion of obesity and other lifestyle-related illnesses among teenagers. Indeed, the design of an engaging strategy, leveraging a complementary set of technologies, is the approach proposed by the project to promote the adoption of healthy habits such as active lifestyle and balanced nutrition and to effectively counter-fight the emergence of overweight and obesity in the younger population. A technological key element of such a strategy sees the adoption of wearable sensors to monitor teenagers' activities, which is at the basis of developing awareness about the current lifestyle. This paper describes the experience carried out in the framework of the PEGASO project in developing and evaluating wearable monitoring systems addressed to adolescents. The paper describes the methodological approach based on the co-designing of such a wearable system and the main results that, in the first phase, involved a total of 407 adolescents across Europe in a series of focus groups conducted in three countries for the requirements definition phase. Moreover, it describes an evaluation process of signal reliability during the usage of the wearable system. The main results described here are: (a) a prototype of the standardized experimental protocol that has been developed and applied to test signal reliability in smart garments; (b) the requirements definition methodology through a co-design activity and approach to address user requirements and preferences and not only technological specifications. Such co-design approach is able to support a higher system acceptance and usability together with a sustained adoption of the solution with respect to the traditional technology push system development strategy.
A Smart Wearable Sensor System for Counter-Fighting Overweight in Teenagers
Standoli, Carlo Emilio; Guarneri, Maria Renata; Perego, Paolo; Mazzola, Marco; Mazzola, Alessandra; Andreoni, Giuseppe
2016-01-01
PEGASO is a FP7-funded project whose goal is to develop an ICT and mobile-based platform together with an appropriate strategy to tackle the diffusion of obesity and other lifestyle-related illnesses among teenagers. Indeed, the design of an engaging strategy, leveraging a complementary set of technologies, is the approach proposed by the project to promote the adoption of healthy habits such as active lifestyle and balanced nutrition and to effectively counter-fight the emergence of overweight and obesity in the younger population. A technological key element of such a strategy sees the adoption of wearable sensors to monitor teenagers’ activities, which is at the basis of developing awareness about the current lifestyle. This paper describes the experience carried out in the framework of the PEGASO project in developing and evaluating wearable monitoring systems addressed to adolescents. The paper describes the methodological approach based on the co-designing of such a wearable system and the main results that, in the first phase, involved a total of 407 adolescents across Europe in a series of focus groups conducted in three countries for the requirements definition phase. Moreover, it describes an evaluation process of signal reliability during the usage of the wearable system. The main results described here are: (a) a prototype of the standardized experimental protocol that has been developed and applied to test signal reliability in smart garments; (b) the requirements definition methodology through a co-design activity and approach to address user requirements and preferences and not only technological specifications. Such co-design approach is able to support a higher system acceptance and usability together with a sustained adoption of the solution with respect to the traditional technology push system development strategy. PMID:27517929
Toward Phase IV, Populating the WOVOdat Database
NASA Astrophysics Data System (ADS)
Ratdomopurbo, A.; Newhall, C. G.; Schwandner, F. M.; Selva, J.; Ueda, H.
2009-12-01
One of challenges for volcanologists is the fact that more and more people are likely to live on volcanic slopes. Information about volcanic activity during unrest should be accurate and rapidly distributed. As unrest may lead to eruption, evacuation may be necessary to minimize damage and casualties. The decision to evacuate people is usually based on the interpretation of monitoring data. Over the past several decades, monitoring volcanoes has used more and more sophisticated instruments. A huge volume of data is collected in order to understand the state of activity and behaviour of a volcano. WOVOdat, The World Organization of Volcano Observatories (WOVO) Database of Volcanic Unrest, will provide context within which scientists can interpret the state of their own volcano, during and between crises. After a decision during the 2000 IAVCEI General Assembly to create WOVOdat, development has passed through several phases, from Concept Development (Phase-I in 2000-2002), Database Design (Phase-II, 2003-2006) and Pilot Testing (Phase-III in 2007-2008). For WOVOdat to be operational, there are still two (2) steps to complete, which are: Database Population (Phase-IV) and Enhancement and Maintenance (Phase-V). Since January 2009, the WOVOdat project is hosted by Earth Observatory of Singapore for at least a 5-year period. According to the original planning in 2002, this 5-year period will be used for completing the Phase-IV. As the WOVOdat design is not yet tested for all types of data, 2009 is still reserved for building the back-end relational database management system (RDBMS) of WOVOdat and testing it with more complex data. Fine-tuning of the WOVOdat’s RDBMS design is being done with each new upload of observatory data. The next and main phase of WOVOdat development will be data population, managing data transfer from multiple observatory formats to WOVOdat format. Data population will depend on two important things, the availability of SQL database in volcano observatories and their data sharing policy. Hence, a strong collaboration with every WOVO observatory is important. For some volcanoes where the data are not in an SQL system, the WOVOdat project will help scientists working on the volcano to start building an SQL database.
Duplaga, Mariusz; Leszczuk, Mikolaj; Zielinski, Krzysztof
2006-01-01
Central and Eastern Europe countries (CEEC) undertook considerable efforts to include themselves in the main research and development activities in the area of health telematics in Europe. Countries of this region demonstrate diversified environments of economy transformation and health care systems status. The transition phase to market economy brings essential risks to the healthcare system performance. It seems that efforts of developing e-health environment in CEEC could be substantially accelerated by extended co-operation with partners from current member states of the European Union. The PRO-ACCESS project was initiated in the late phase of fifth Framework Programme as supporting action. It focused on the transfer of current concepts in medical telematics to countries remaining in the pre-accession phase. The process of dissemination of up-to-date approaches to e-health environment development is carried out by the Krakow Centre of Telemedicine and is supported by leading health telematics centres in Europe. To accelerate the dissemination activities the network of co-operating centres in CEEC was established. The strategy employed within the PRO-ACCESS project is supposed to yield "critical mass" necessary for facilitating the e-health development in this region of Europe. The activities employed to reach this objective included publishing activities, events and trainings as well as intake of solutions from supporting centres.
Flow structure and aerodynamic performance of a hovering bristled wing in low Re
NASA Astrophysics Data System (ADS)
Lee, Seunghun; Lahooti, Mohsen; Kim, Daegyoum
2017-11-01
Previous studies on a bristled wing have mainly focused on simple kinematics of the wing such as translation or rotation. The aerodynamic performance of a bristled wing in a quasi-steady phase is known to be comparable to that of a smooth wing without a gap because shear layers in the gaps of the bristled wing are sufficiently developed to block the gaps. However, we point out that, in the starting transient phase where the shear layers are not fully developed, the force generation of a bristled wing is not as efficient as that of a quasi-steady state. The performance in the transient phase is important to understand the aerodynamics of a bristled wing in an unsteady motion. In the hovering motion, due to repeated stroke reversals, the formation and development of shear layers inside the gaps is repeated in each stroke. In this study, a bristled wing in hovering is numerically investigated in the low Reynolds number of O(10). We especially focus on the development of shear layers during a stroke reversal and its effect on the overall propulsive performance. Although the aerodynamic force generation is slightly reduced due to the gap vortices, the asymmetric behavior of vortices in a gap between bristles during a stroke reversal makes the bristled wing show higher lift to drag ratio than a smooth wing.
Bolanča, Tomislav; Marinović, Slavica; Ukić, Sime; Jukić, Ante; Rukavina, Vinko
2012-06-01
This paper describes development of artificial neural network models which can be used to correlate and predict diesel fuel properties from several FTIR-ATR absorbances and Raman intensities as input variables. Multilayer feed forward and radial basis function neural networks have been used to rapid and simultaneous prediction of cetane number, cetane index, density, viscosity, distillation temperatures at 10% (T10), 50% (T50) and 90% (T90) recovery, contents of total aromatics and polycyclic aromatic hydrocarbons of commercial diesel fuels. In this study two-phase training procedures for multilayer feed forward networks were applied. While first phase training algorithm was constantly the back propagation one, two second phase training algorithms were varied and compared, namely: conjugate gradient and quasi Newton. In case of radial basis function network, radial layer was trained using K-means radial assignment algorithm and three different radial spread algorithms: explicit, isotropic and K-nearest neighbour. The number of hidden layer neurons and experimental data points used for the training set have been optimized for both neural networks in order to insure good predictive ability by reducing unnecessary experimental work. This work shows that developed artificial neural network models can determine main properties of diesel fuels simultaneously based on a single and fast IR or Raman measurement.
Marbjerg, Gerd; Brunskog, Jonas; Jeong, Cheol-Ho; Nilsson, Erling
2015-09-01
A model, combining acoustical radiosity and the image source method, including phase shifts on reflection, has been developed. The model is denoted Phased Acoustical Radiosity and Image Source Method (PARISM), and it has been developed in order to be able to model both specular and diffuse reflections with complex-valued and angle-dependent boundary conditions. This paper mainly describes the combination of the two models and the implementation of the angle-dependent boundary conditions. It furthermore describes how a pressure impulse response is obtained from the energy-based acoustical radiosity by regarding the model as being stochastic. Three methods of implementation are proposed and investigated, and finally, recommendations are made for their use. Validation of the image source method is done by comparison with finite element simulations of a rectangular room with a porous absorber ceiling. Results from the full model are compared with results from other simulation tools and with measurements. The comparisons of the full model are done for real-valued and angle-independent surface properties. The proposed model agrees well with both the measured results and the alternative theories, and furthermore shows a more realistic spatial variation than energy-based methods due to the fact that interference is considered.
Letica, Jelena; Marković, Slavko; Zirojević, Jelena; Nikolić, Katarina; Agbaba, Danica
2010-01-01
An RP-HPLC method for simultaneous separation and quantification of pantoprazole and its five main impurities in pharmaceutical formulations was developed and validated. The separation was accomplished on a Zorbax Eclipse XDB C18 column (5 microm particle size, 150 x 4.6 mm id) using a gradient with mobile phase A [buffer-acetonitrile (70 + 30, v/v)], and mobile phase B [buffer-acetonitrile (30 + 70, v/v)]. The buffer was 0.01 M ammonium acetate solution with addition of 1 mL triethylamine/L of the solution, adjusted to pH 4.5 with orthophosphoric acid. The eluent flow rate was 1 mL/min, the temperature of the column was 30 degrees C, and the eluate was monitored at 290 nm. Linearity (r = 0.999), recovery (97.6-105.8%), RSD (0.55-1.90%), and LOQ (0.099-1.48 microg/mL) were evaluated and found to be satisfactory. The proposed method can be used for simultaneous identification and quantification of the analyzed compounds in pharmaceutical formulations.
RF pulse shape control in the compact linear collider test facility
NASA Astrophysics Data System (ADS)
Kononenko, Oleksiy; Corsini, Roberto
2018-07-01
The Compact Linear Collider (CLIC) is a study for an electron-positron machine aiming at accelerating and colliding particles at the next energy frontier. The CLIC concept is based on the novel two-beam acceleration scheme, where a high-current low-energy drive beam generates RF in series of power extraction and transfer structures accelerating the low-current main beam. To compensate for the transient beam-loading and meet the energy spread specification requirements for the main linac, the RF pulse shape must be carefully optimized. This was recently modelled by varying the drive beam phase switch times in the sub-harmonic buncher so that, when combined, the drive beam modulation translates into the required voltage modulation of the accelerating pulse. In this paper, the control over the RF pulse shape with the phase switches, that is crucial for the success of the developed compensation model, is studied. The results on the experimental verification of this control method are presented and a good agreement with the numerical predictions is demonstrated. Implications for the CLIC beam-loading compensation model are also discussed.
Design and control of the phase current of a brushless dc motor to eliminate cogging torque
NASA Astrophysics Data System (ADS)
Jang, G. H.; Lee, C. J.
2006-04-01
This paper presents a design and control method of the phase current to reduce the torque ripple of a brushless dc (BLDC) motor by eliminating cogging torque. The cogging torque is the main source of torque ripple and consequently of speed error, and it is also the excitation source to generate the vibration and noise of a motor. This research proposes a modified current wave form, which is composed of main and auxiliary currents. The former is the conventional current to generate the commutating torque. The latter generates the torque with the same magnitude and opposite sign of the corresponding cogging torque at the given position in order to eliminate the cogging torque. Time-stepping finite element method simulation considering pulse-width-modulation switching method has been performed to verify the effectiveness of the proposed method, and it shows that this proposed method reduces torque ripple by 36%. A digital-signal-processor-based controller is also developed to implement the proposed method, and it shows that this proposed method reduces the speed ripple significantly.
Powder formation of {gamma} uranium-molybdenum alloys via hydration-dehydration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vaz de Oliveira, Fabio Branco; Durazzo, Michelangelo; Fontenele Urano de Carvalho, Elita
2008-07-15
Gamma uranium-molybdenum alloys has been considered as fuel phase in plate type fuel elements for MTR reactors, mainly due to their acceptable performance under irradiation and metallurgical processing. To its use as a dispersion phase in aluminum matrix, a necessary step is the conversion of the as cast structure into powder, and one of the techniques considered at IPEN / CNEN - Brazil is HDH (hydration-dehydration). The alloys were produced by the induction melting technique, and samples were obtained from the alloys for the thermal treatments, under constant flow of hydrogen, for temperatures varying from 400 deg C to 600more » deg C and times from 1 to 4 hours, followed by dehydration. A preliminary characterization of the powders was made and the curves of mass variation versus time were obtained and related to the powder characteristics. This paper describes the first results on the development of the technology to the powder formation of the (5 to 10) % weight molybdenum {gamma}-UMo alloys, and discusses some of its aspects, mainly those related to the {gamma} {yields} {alpha} equilibrium data. (author)« less
Melt Flow Control in the Directional Solidification of Binary Alloys
NASA Technical Reports Server (NTRS)
Zabaras, Nicholas
2003-01-01
Our main project objectives are to develop computational techniques based on inverse problem theory that can be used to design directional solidification processes that lead to desired temperature gradient and growth conditions at the freezing front at various levels of gravity. It is known that control of these conditions plays a significant role in the selection of the form and scale of the obtained solidification microstructures. Emphasis is given on the control of the effects of various melt flow mechanisms on the local to the solidification front conditions. The thermal boundary conditions (furnace design) as well as the magnitude and direction of an externally applied magnetic field are the main design variables. We will highlight computational design models for sharp front solidification models and briefly discuss work in progress toward the development of design techniques for multi-phase volume-averaging based solidification models.
Structural and Lithologic Characterization of the SAFOD Pilot Hole and Phase One Main Hole
NASA Astrophysics Data System (ADS)
Barton, D. C.; Bradbury, K.; Solum, J. G.; Evans, J. P.
2005-12-01
Petrological and microstructural analyses of drill cuttings were conducted for the San Andreas Fault Observatory at Depth (SAFOD) Pilot Hole and Main Hole projects. Grain mounts were produced at ~30 m (100 ft) intervals from drill cuttings collected from the Pilot Hole to a depth of 2164 m (7100 ft) and from Phase 1 of the SAFOD main hole to a depth of 3067 m (10062 ft). . Thin-section grain mount analysis included identification of mineral composition, alteration, and deformation within individual grains, measured at .5 mm increments on an equally spaced, 300 point grid pattern. Lithologic features in the Quaternary/Tertiary deposits from 30 - 640 m (100-2100 ft) in the Pilot Hole, and 670 - 792 m (2200 - 2600 ft) in the Phase 1 main hole, include fine-grained, thinly bedded sediments with clasts of fine-grained volcanic groundmass. Preliminary grain mount analysis from 1920 - 3067 m (6300 - 10062) in the Phase 1 main hole, indicates a sedimentary sequence consisting of fine-grained lithic fragments of very fine-grained shale. Deformation mechanisms observed within the cuttings of granitic rocks from 914 - 1860 m (3000 - 6100 ft.) include intracrystalline plasticity and cataclasis. Intracrystalline plastic deformation within quartz and feldspar grains is indicated by undulatory extinction, ribbon grains, chessboard patterns, and deformation twins and lamellae. Cataclastic deformation is characterized by intra- and intergranular microfractures, angular grains, gouge zones, iron-oxide banding, and comminution. Mineral and cataclasite abundances were plotted as a function of weight percent vs. depth. Plots of quartz and feldspar abundances are also correlated with XRD weight percent data from 1160 - 1890 m (3800 - 6200 ft.) in the granitic and granodioritic sequences of the Phase 1 main hole. Regions of the both of the drill holes with cataclasite abundances ranging from 20 - 30 wt% are interpreted as shear zones. Shear zones identified in this study from 1150 - 1420 m (3773 - 4659 ft.) in the Pilot Hole occur in the same location as shear zones recognized by Boness and Zoback (2004) using borehole geophysical data. These shear zones may possibly be correlated to shear zones identified in the Phase I main hole from 1615 - 2012 m (5300 - 6600 ft). If this is the case, it can be explained by steeply dipping subsidiary fault zones, likely associated with the San Andreas Fault system.
GIOVE-A: Two Years of Galileo Signals
NASA Astrophysics Data System (ADS)
Davies, P.; da Silva Curiel, A.; Rooney, E.; Sweeting, M.; Gattia, G.
2008-08-01
During 2007, the GIOVE-A mission has transitioned from an experimental mission into what is effectively an operational mission. The small satellite approach used in the development of the mission, and the lessons learned from this mission, are being applied in the development of SSTL's Geostationary communication satellite platform. Furthermore, ESA has also been considering the lessons learned from small low-cost, rapid-response missions such as GIOVE with a view to a new procurement approach for such "entry-level" missions. On 28 December 2005 the first satellite in the Galileo programme was launched into space. The satellite, GIOVE-A, was developed for the European Space Agency (ESA) under a contract signed in July 2003. Since January 2006 GIOVE-A has broadcast the Galileo signal enabling Europe to claim the ITU frequency filing, to qualify the Galileo payload equipment, to characterise the performance of the Galileo system and to develop ground receiving equipment. The satellite was built for a relatively low-cost, €28M, within a very rapid timescale - from contract signature to flight readiness in 28 months. In order to meet this timescale SSTL used a development approach similar to the one it uses for its range of microsatellites. Further, the GIOVE-A satellite carries many pieces of equipment from the microsatellite range integrated into a larger structure, and in-flight results with the COTS parts are now showing that these are holding up well in the harsh MEO environment. The development approach was very different from a typical ESA operational mission and formed one of the reference inputs to the "Lightsat" approach which ESA will employ on some of its future projects. The paper will cover the main results and lessons learned from the GIOVE-A mission. We will describe the small satellite approach to its development and the main lessons learned from the development phase. We will also cover the main results of the mission since launch concentrating on the initial phase during 2006 when the payload was exercised to achieve the initial mission goals. We will then describe the routine operations performed during 2007 which led to the satellite achieving close to 100% availability whilst employing a very low cost operational concept without full-time operations staff.
3D Micro-tomography on Aggregates from the 2014- 2015 Eruption of Hunga Tonga-Hunga Ha'apai Volcano
NASA Astrophysics Data System (ADS)
Colombier, M.; Scheu, B.; Cronin, S. J.; Tost, M.; Dobson, K. J.; Dingwell, D. B.
2016-12-01
In December 2014- January 2015, a surtseyan eruption at Hunga Tonga-Hunga Ha'apai volcano (Tonga) formed a new island. Three main eruptive phases were distinguished by observation and deposits: (i) mound and cone construction, involving collapse of 300-600 m-high wet tephra jets, grain flows, slope-remobilisation and energetic surges, with little or no convective plume (ii) The upper cone-building phase with lower jets (mainly <300 m) but greater ash production (weak, steam-rich plumes to 6 km) and weak surges, and (iii) final phase with weak surge, fall and ballistic deposits with more vesicular pyroclasts producing proximal capping deposits. Most sampled deposits contain ash, lapilli and bombs, and lapilli-sized aggregates are ubiquitous. We used high-resolution 3D X-ray microcomputed tomography (XCT) to quantify the grain size distribution (GSD) and porosity by sampling multiple stratigraphic units within the main eruptive sequences. We visualized and quantified the internal structure of the aggregates to understand the evolution of this surtseyan eruption. We present here an overview of the textural information: porosity, vesicle size distribution and morphology as well as the variability of the aggregation features. Aggregates from the fall deposits of the early wet phase are mostly loosely packed, poorly-structured ash clusters. Aggregates from the early surge sequence and the main cone building phase dominantly exhibit a central particle coated by ash cluster material. Vesicles in the particles from the early fall deposits tend to be smaller and more isolated than in the particles from the surge sequence and the main cone building phase. The GSD of aggregates obtained by XCT is highly valuable to correct the total GSD of volcaniclastic deposits. The strong variations in the aggregation features across the eruption suggest a range of different formation and deposition mechanisms related to varying degrees of magma-water-interaction, which changed the morphology and textural properties of the individual particles.
Jovanović, Marko; Rakić, Tijana; Tumpa, Anja; Jančić Stojanović, Biljana
2015-06-10
This study presents the development of hydrophilic interaction liquid chromatographic method for the analysis of iohexol, its endo-isomer and three impurities following Quality by Design (QbD) approach. The main objective of the method was to identify the conditions where adequate separation quality in minimal analysis duration could be achieved within a robust region that guarantees the stability of method performance. The relationship between critical process parameters (acetonitrile content in the mobile phase, pH of the water phase and ammonium acetate concentration in the water phase) and critical quality attributes is created applying design of experiments methodology. The defined mathematical models and Monte Carlo simulation are used to evaluate the risk of uncertainty in models prediction and incertitude in adjusting the process parameters and to identify the design space. The borders of the design space are experimentally verified and confirmed that the quality of the method is preserved in this region. Moreover, Plackett-Burman design is applied for experimental robustness testing and method is fully validated to verify the adequacy of selected optimal conditions: the analytical column ZIC HILIC (100 mm × 4.6 mm, 5 μm particle size); mobile phase consisted of acetonitrile-water phase (72 mM ammonium acetate, pH adjusted to 6.5 with glacial acetic acid) (86.7:13.3) v/v; column temperature 25 °C, mobile phase flow rate 1 mL min(-1), wavelength of detection 254 nm. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Yuhang, X.
2017-12-01
A pumping test was carried out to explore the transfer rules of pressure drop in coal reservoir during the drainage. The experiment was divided into three stages. In the first stage, the pump displacement of 3m3/h was used to reduce the bottom hole flowing pressure and stopped until the continuous gas phase was produced; Undertaking the first stage, in the second stage, when the gas phase was continuously produced, the pump was stopped immediately. As the bottom hole flowing pressure going up without gas phase, pumping started again for a week. In the third stage ,the well pumping was carried out at the bottom hole pressure drop rate of 30Kpa/d after two months' recovery. Combined with the data of regional geology and fractured well, taking the characteristics of macroscopic coal rocks, development of pore and fracture in coal and isothermal adsorption test as the background, the features of reservoir output in each stage of the experiment were analyzed and compared, and then the transfer rules of pressure drop contained in the differences of the output was studied further. In the first and third stage of the experiment, the output of liquid phase was much larger than the space volume of coal reservoir pore and fracture in the range of 100m2. In the second stage, the output of the continuous gas phase appeared around 0.7Mpa when the continuous gas phase appears below the critical desorption pressure of 0.25Mpa during the whole experiment. The results indicate that, the transfer of pressure drop in the coal reservoir of this well is mainly horizontal, and the liquid phase produced in the reservoir mainly comes from the recharge of the reservoir at the far end of the relative high pressure area; the adsorption space of coalbed methane in the coal matrix as well as the main migration channel of fluid in the reservoir doesn't belong to the same pressure system and there exists the communication barrier between them. In addition, the increasing of the effective stress has little influence on the communication between these two systems. The definition of transfer rules in coal reservoir pressure drop, also the understanding of the correlation between the rules and characteristics of the reservoir output has great guiding significance to the establishment of pressure drop system in coalbed methane well as well as the analysis of production problems.
NASA Astrophysics Data System (ADS)
Pistolesi, Marco; Cioni, Raffaello; Bonadonna, Costanza; Elissondo, Manuela; Baumann, Valerie; Bertagnini, Antonella; Chiari, Laura; Gonzales, Rafael; Rosi, Mauro; Francalanci, Lorella
2015-01-01
After decades of repose, Puyehue-Cordón Caulle Volcano (Chile) erupted in June 2011 following a month of continuously increasing seismic activity. The eruption dispersed a large volume of rhyolitic tephra over a wide area and was characterized by complex dynamics. During the initial climactic phase of the eruption (24-30 h on 4-5 June), 11-14-km-high plumes dispersed most of the erupted tephra eastward towards Argentina, reaching as far as the Atlantic Ocean. This first eruptive phase was followed by activity of lower intensity, leading to the development of a complex stratigraphic sequence, mainly due to rapid shifts in wind direction and eruptive style. The resulting tephra deposits consist of 13 main layers grouped into four units. Each layer was characterized based on its dispersal direction, sedimentological features, and on the main characteristics of the juvenile fraction (texture, density, petrography, chemistry). The lowest part of the eruptive sequence (Unit I), corresponding to the tephra emitted between 4 and 5 June, is composed of alternating lapilli layers with a total estimated volume of ca. 0.75 km3; these layers record the highest intensity phase, during which a bent-over plume dispersed tephra towards the southeast-east, with negligible up-wind sedimentation. Products emitted during 5-6 June (Unit II) signaled an abrupt shift in wind direction towards the north, leading to the deposition of a coarse ash deposit in the northern sector (ca. 0.21 km3 in volume), followed by a resumption of easterly directed winds. A third phase (Unit III) began on 7 June and resulted in tephra deposits in the eastern sector and ballistic bombs around the vent area. A final phase (Unit IV) started after 15 June and was characterized by the emission of fine-grained white tephra from ash-charged plumes during low-level activity and the extrusion of a viscous lava flow. Timing and duration of the first eruptive phases were constrained based on comparison of the dispersal of the main tephra layers with satellite images, showing that most of the tephra was emitted during the first 72 h of the event. The analyzed juvenile material tightly clusters within the rhyolitic field, with negligible chemical variations through the eruptive sequence. Textural observations reveal that changes in eruption intensity (and consequently in magma ascent velocity within the conduit) and complex interactions between gas-rich and gas-depleted magma portions during ascent resulted in vesicular clasts with variable degrees of shear localization, and possibly in the large heterogeneity of the juvenile material.
The preparatory phase of the April 6th 2009, Mw 6.3, L’Aquila earthquake: Seismological observations
NASA Astrophysics Data System (ADS)
Lucente, F. P.; de Gori, P.; Margheriti, L.; Piccinini, D.; Dibona, M.; Chiarabba, C.; Piana Agostinetti, N.
2009-12-01
Few decades ago, the dilatancy-diffusion hypothesis held great promise as a physical basis for developing earthquakes prediction techniques, but the potential never become reality, as the result of too few observations consistent with the theory. One of the main problems has been the lack of detailed monitoring records of small earthquakes swarms spatio-temporally close to the incoming major earthquakes. In fact, the recognition of dilatancy-related effects requires the use of very dense network of three-component seismographs, which, in turn, implies the a-priori knowledge of major earthquakes location, i.e., actually a paradox. The deterministic prediction of earthquakes remains a long time, hard task to accomplish. Nevertheless, for seismologists, the understanding of the processes that preside over the earthquakes nucleation and the mechanics of faulting represents a big step toward the ability to predict earthquakes. Here we describe a set of seismological observations done on the foreshock sequence that preceded the April 6th 2009, Mw 6.3, L’Aquila earthquake. In this occasion, the dense configuration of the seismic network in the area gave us the unique opportunity for a detailed reconstruction of the preparatory phase of the main shock. We show that measurable precursory effects, as changes of the seismic waves velocity and of the anisotropic parameters in the crust, occurred before the main shock. From our observations we infer that fluids play a key role in the fault failure process, and, most significantly, that the elastic properties of the rock volume surrounding the main shock nucleation area undergo a dramatic change about a week before the main shock occurrence.
Kephalopoulos, Stylianos; Paviotti, Marco; Anfosso-Lédée, Fabienne; Van Maercke, Dirk; Shilton, Simon; Jones, Nigel
2014-06-01
The Environmental Noise Directive (2002/49/EC) requires EU Member States to determine the exposure to environmental noise through strategic noise mapping and to elaborate action plans in order to reduce noise pollution, where necessary. A common framework for noise assessment methods (CNOSSOS-EU) has been developed by the European Commission in co-operation with the EU Member States to be applied for strategic noise mapping as required by the Environment Noise Directive (2002/49/EC). CNOSSOS-EU represents a harmonised and coherent approach to assess noise levels from the main sources of noise (road traffic, railway traffic, aircraft and industrial) across Europe. This paper outlines the process behind the development of CNOSSOS-EU and the parts of the CNOSSOS-EU core methodological framework which were developed during phase A of the CNOSSOS-EU process (2010-2012), whilst focusing on the main scientific and technical issues that were addressed, and the implementation challenges that are being faced before it can become fully operational in the EU MS. Copyright © 2014. Published by Elsevier B.V.
Clinical development of gene- and cell-based therapies: overview of the European landscape
de Wilde, Sofieke; Guchelaar, Henk-Jan; Zandvliet, Maarten Laurens; Meij, Pauline
2016-01-01
In the last decade, many clinical trials with gene- and cell-based therapies were performed and increasing interest in the development was established by (national) authorities, academic developers, and commercial companies. However, until now only eight products have received marketing authorization (MA) approval. In this study, a comprehensive overview of the clinical development of gene- and cell-based therapies in Europe is presented, with a strong focus on product-technical aspects. Public data regarding clinical trials with gene- and cell-based therapies, obtained from the European Union (EU) clinical trial database (EudraCT) between 2004 and 2014 were analyzed, including product-technical variables as potential determinants affecting development. 198 unique gene and cell therapy products were identified, which were studied in 278 clinical trials, mostly in phase 1/2 trials and with cell therapies as major group. Furthermore, most products were manufactured from autologous starting material mostly manufactured from stem cells. The majority of the trials were sponsored by academia, whereas phase 3 trials mostly by large companies. Academia dominated early-stage development by mainly using bone marrow derived products and stem cells. Conversely, commercial sponsors were more actively pursuing in vivo gene therapy medicinal product development, and cell therapies derived from differentiated tissue in later-stage development. PMID:27990447
Transcriptomic and metabolite analyses of Cabernet Sauvignon grape berry development.
Deluc, Laurent G; Grimplet, Jérôme; Wheatley, Matthew D; Tillett, Richard L; Quilici, David R; Osborne, Craig; Schooley, David A; Schlauch, Karen A; Cushman, John C; Cramer, Grant R
2007-11-22
Grape berry development is a dynamic process that involves a complex series of molecular genetic and biochemical changes divided into three major phases. During initial berry growth (Phase I), berry size increases along a sigmoidal growth curve due to cell division and subsequent cell expansion, and organic acids (mainly malate and tartrate), tannins, and hydroxycinnamates accumulate to peak levels. The second major phase (Phase II) is defined as a lag phase in which cell expansion ceases and sugars begin to accumulate. Véraison (the onset of ripening) marks the beginning of the third major phase (Phase III) in which berries undergo a second period of sigmoidal growth due to additional mesocarp cell expansion, accumulation of anthocyanin pigments for berry color, accumulation of volatile compounds for aroma, softening, peak accumulation of sugars (mainly glucose and fructose), and a decline in organic acid accumulation. In order to understand the transcriptional network responsible for controlling berry development, mRNA expression profiling was conducted on berries of V. vinifera Cabernet Sauvignon using the Affymetrix GeneChip Vitis oligonucleotide microarray ver. 1.0 spanning seven stages of berry development from small pea size berries (E-L stages 31 to 33 as defined by the modified E-L system), through véraison (E-L stages 34 and 35), to mature berries (E-L stages 36 and 38). Selected metabolites were profiled in parallel with mRNA expression profiling to understand the effect of transcriptional regulatory processes on specific metabolite production that ultimately influence the organoleptic properties of wine. Over the course of berry development whole fruit tissues were found to express an average of 74.5% of probes represented on the Vitis microarray, which has 14,470 Unigenes. Approximately 60% of the expressed transcripts were differentially expressed between at least two out of the seven stages of berry development (28% of transcripts, 4,151 Unigenes, had pronounced (> or =2 fold) differences in mRNA expression) illustrating the dynamic nature of the developmental process. The subset of 4,151 Unigenes was split into twenty well-correlated expression profiles. Expression profile patterns included those with declining or increasing mRNA expression over the course of berry development as well as transient peak or trough patterns across various developmental stages as defined by the modified E-L system. These detailed surveys revealed the expression patterns for genes that play key functional roles in phytohormone biosynthesis and response, calcium sequestration, transport and signaling, cell wall metabolism mediating expansion, ripening, and softening, flavonoid metabolism and transport, organic and amino acid metabolism, hexose sugar and triose phosphate metabolism and transport, starch metabolism, photosynthesis, circadian cycles and pathogen resistance. In particular, mRNA expression patterns of transcription factors, abscisic acid (ABA) biosynthesis, and calcium signaling genes identified candidate factors likely to participate in the progression of key developmental events such as véraison and potential candidate genes associated with such processes as auxin partitioning within berry cells, aroma compound production, and pathway regulation and sequestration of flavonoid compounds. Finally, analysis of sugar metabolism gene expression patterns indicated the existence of an alternative pathway for glucose and triose phosphate production that is invoked from véraison to mature berries. These results reveal the first high-resolution picture of the transcriptome dynamics that occur during seven stages of grape berry development. This work also establishes an extensive catalog of gene expression patterns for future investigations aimed at the dissection of the transcriptional regulatory hierarchies that govern berry development in a widely grown cultivar of wine grape. More importantly, this analysis identified a set of previously unknown genes potentially involved in critical steps associated with fruit development that can now be subjected to functional testing.
Transcriptomic and metabolite analyses of Cabernet Sauvignon grape berry development
Deluc, Laurent G; Grimplet, Jérôme; Wheatley, Matthew D; Tillett, Richard L; Quilici, David R; Osborne, Craig; Schooley, David A; Schlauch, Karen A; Cushman, John C; Cramer, Grant R
2007-01-01
Background Grape berry development is a dynamic process that involves a complex series of molecular genetic and biochemical changes divided into three major phases. During initial berry growth (Phase I), berry size increases along a sigmoidal growth curve due to cell division and subsequent cell expansion, and organic acids (mainly malate and tartrate), tannins, and hydroxycinnamates accumulate to peak levels. The second major phase (Phase II) is defined as a lag phase in which cell expansion ceases and sugars begin to accumulate. Véraison (the onset of ripening) marks the beginning of the third major phase (Phase III) in which berries undergo a second period of sigmoidal growth due to additional mesocarp cell expansion, accumulation of anthocyanin pigments for berry color, accumulation of volatile compounds for aroma, softening, peak accumulation of sugars (mainly glucose and fructose), and a decline in organic acid accumulation. In order to understand the transcriptional network responsible for controlling berry development, mRNA expression profiling was conducted on berries of V. vinifera Cabernet Sauvignon using the Affymetrix GeneChip® Vitis oligonucleotide microarray ver. 1.0 spanning seven stages of berry development from small pea size berries (E-L stages 31 to 33 as defined by the modified E-L system), through véraison (E-L stages 34 and 35), to mature berries (E-L stages 36 and 38). Selected metabolites were profiled in parallel with mRNA expression profiling to understand the effect of transcriptional regulatory processes on specific metabolite production that ultimately influence the organoleptic properties of wine. Results Over the course of berry development whole fruit tissues were found to express an average of 74.5% of probes represented on the Vitis microarray, which has 14,470 Unigenes. Approximately 60% of the expressed transcripts were differentially expressed between at least two out of the seven stages of berry development (28% of transcripts, 4,151 Unigenes, had pronounced (≥2 fold) differences in mRNA expression) illustrating the dynamic nature of the developmental process. The subset of 4,151 Unigenes was split into twenty well-correlated expression profiles. Expression profile patterns included those with declining or increasing mRNA expression over the course of berry development as well as transient peak or trough patterns across various developmental stages as defined by the modified E-L system. These detailed surveys revealed the expression patterns for genes that play key functional roles in phytohormone biosynthesis and response, calcium sequestration, transport and signaling, cell wall metabolism mediating expansion, ripening, and softening, flavonoid metabolism and transport, organic and amino acid metabolism, hexose sugar and triose phosphate metabolism and transport, starch metabolism, photosynthesis, circadian cycles and pathogen resistance. In particular, mRNA expression patterns of transcription factors, abscisic acid (ABA) biosynthesis, and calcium signaling genes identified candidate factors likely to participate in the progression of key developmental events such as véraison and potential candidate genes associated with such processes as auxin partitioning within berry cells, aroma compound production, and pathway regulation and sequestration of flavonoid compounds. Finally, analysis of sugar metabolism gene expression patterns indicated the existence of an alternative pathway for glucose and triose phosphate production that is invoked from véraison to mature berries. Conclusion These results reveal the first high-resolution picture of the transcriptome dynamics that occur during seven stages of grape berry development. This work also establishes an extensive catalog of gene expression patterns for future investigations aimed at the dissection of the transcriptional regulatory hierarchies that govern berry development in a widely grown cultivar of wine grape. More importantly, this analysis identified a set of previously unknown genes potentially involved in critical steps associated with fruit development that can now be subjected to functional testing. PMID:18034876
Passivity-based Robust Control of Aerospace Systems
NASA Technical Reports Server (NTRS)
Kelkar, Atul G.; Joshi, Suresh M. (Technical Monitor)
2000-01-01
This report provides a brief summary of the research work performed over the duration of the cooperative research agreement between NASA Langley Research Center and Kansas State University. The cooperative agreement which was originally for the duration the three years was extended by another year through no-cost extension in order to accomplish the goals of the project. The main objective of the research was to develop passivity-based robust control methodology for passive and non-passive aerospace systems. The focus of the first-year's research was limited to the investigation of passivity-based methods for the robust control of Linear Time-Invariant (LTI) single-input single-output (SISO), open-loop stable, minimum-phase non-passive systems. The second year's focus was mainly on extending the passivity-based methodology to a larger class of non-passive LTI systems which includes unstable and nonminimum phase SISO systems. For LTI non-passive systems, five different passification. methods were developed. The primary effort during the years three and four was on the development of passification methodology for MIMO systems, development of methods for checking robustness of passification, and developing synthesis techniques for passifying compensators. For passive LTI systems optimal synthesis procedure was also developed for the design of constant-gain positive real controllers. For nonlinear passive systems, numerical optimization-based technique was developed for the synthesis of constant as well as time-varying gain positive-real controllers. The passivity-based control design methodology developed during the duration of this project was demonstrated by its application to various benchmark examples. These example systems included longitudinal model of an F-18 High Alpha Research Vehicle (HARV) for pitch axis control, NASA's supersonic transport wind tunnel model, ACC benchmark model, 1-D acoustic duct model, piezo-actuated flexible link model, and NASA's Benchmark Active Controls Technology (BACT) Wing model. Some of the stability results for linear passive systems were also extended to nonlinear passive systems. Several publications and conference presentations resulted from this research.
NASA Astrophysics Data System (ADS)
Mitani, K.; Seki, K.; Keika, K.; Gkioulidou, M.; Lanzerotti, L. J.; Mitchell, D. G.; Kletzing, C.
2017-12-01
It is known that proton is main contributor of the ring current and oxygen ions can make significant contribution during major magnetic storms. Ions are supplied to the ring current by radial transport from the plasma sheet. Convective transport of lower-energy protons and diffusive transport of higher-energy protons were reported to contribute to the storm-time and quiet-time ring current respectively [e.g., Gkioulidou et al., 2016]. However, supply mechanisms of the oxygen ions are not clear. To characterize the supply of oxygen ions to the ring current during magnetic storms, we studied the properties of energetic proton and oxygen ion phase space densities (PSDs) for specific magnetic moment (μ) during the April 23-25, 2013, geomagnetic storm observed by the Van Allen Probes mission. We here report on radial transport of high-energy (μ ≥ 0.5 keV/nT) oxygen ions into the deep inner magnetosphere during the late main phase of the magnetic storm. Since protons show little change during this period, this oxygen radial transport is inferred to cause the development of the late main phase. Enhancement of poloidal magnetic fluctuations is simultaneously observed. We estimated azimuthal mode number ≤5 by using cross wavelet analysis with ground-based observation of IMAGE ground magnetometers. The fluctuations can resonate with drift and bounce motions of the oxygen ions. The results suggest that combination of the drift and drift-bounce resonances is responsible for the radial transport of high-energy oxygen ions into the deep inner magnetosphere. We also report on the radial transport of the high-energy oxygen ions into the deep inner magnetosphere during other magnetic storms.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campbell, Keri R.; Judge, Elizabeth J.; Barefield, James E.
We show the analysis of light water reactor simulated used nuclear fuel using laser-induced breakdown spectroscopy (LIBS) is explored using a simplified version of the main oxide phase. The main oxide phase consists of the actinides, lanthanides, and zirconium. The purpose of this study is to develop a rapid, quantitative technique for measuring zirconium in a uranium dioxide matrix without the need to dissolve the material. A second set of materials including cerium oxide is also analyzed to determine precision and limit of detection (LOD) using LIBS in a complex matrix. Two types of samples are used in this study:more » binary and ternary oxide pellets. The ternary oxide, (U,Zr,Ce)O 2 pellets used in this study are a simplified version the main oxide phase of used nuclear fuel. The binary oxides, (U,Ce)O 2 and (U,Zr)O 2 are also examined to determine spectral emission lines for Ce and Zr, potential spectral interferences with uranium and baseline LOD values for Ce and Zr in a UO 2 matrix. In the spectral range of 200 to 800 nm, 33 cerium lines and 25 zirconium lines were identified and shown to have linear correlation values (R 2) > 0.97 for both the binary and ternary oxides. The cerium LOD in the (U,Ce)O 2 matrix ranged from 0.34 to 1.08 wt% and 0.94 to 1.22 wt% in (U,Ce,Zr)O 2 for 33 of Ce emission lines. The zirconium limit of detection in the (U,Zr)O 2 matrix ranged from 0.84 to 1.15 wt% and 0.99 to 1.10 wt% in (U,Ce,Zr)O 2 for 25 Zr lines. Finally, the effect of multiple elements in the plasma and the impact on the LOD is discussed.« less
Morrison, Deborah; Mair, Frances S; Chaudhuri, Rekha; McGee-Lennon, Marilyn; Thomas, Mike; Thomson, Neil C; Yardley, Lucy; Wyke, Sally
2015-07-28
Around 300 million people worldwide have asthma and prevalence is increasing. Self-management can be effective in improving a range of outcomes and is cost effective, but is underutilised as a treatment strategy. Supporting optimum self-management using digital technology shows promise, but how best to do this is not clear. We aimed to develop an evidence based, theory informed, online resource to support self-management in adults with asthma, called 'Living well with Asthma', as part of the RAISIN (Randomized Trial of an Asthma Internet Self-Management Intervention) study. We developed Living well with Asthma in two phases. Phase 1: A low fidelity prototype (paper-based) version of the website was developed iteratively through input from a multidisciplinary expert panel, empirical evidence from the literature, and potential end users via focus groups (adults with asthma and practice nurses). Implementation and behaviour change theories informed this process. Phase 2: The paper-based designs were converted to a website through an iterative user centred process. Adults with asthma (n = 10) took part in think aloud studies, discussing the paper based version, then the web-based version. Participants considered contents, layout, and navigation. Development was agile using feedback from the think aloud sessions immediately to inform design and subsequent think aloud sessions. Think aloud transcripts were also thematically analysed, further informing resource development. The website asked users to aim to be symptom free. Key behaviours targeted to achieve this include: optimising medication use (including inhaler technique); attending primary care asthma reviews; using asthma action plans; increasing physical activity levels; and stopping smoking. The website had 11 sections, plus email reminders, which promoted these behaviours. Feedback on the contents of the resource was mainly positive with most changes focussing on clarification of language, order of pages and usability issues mainly relating to navigation difficulties. Our multifaceted approach to online intervention development underpinned by theory, using evidence from the literature, co-designed with end users and a multidisciplinary panel has resulted in a resource which end users find relevant to their needs and easy to use. Living well with Asthma is undergoing evaluation within a randomized controlled trial.
Therapist competencies necessary for the delivery of compassion-focused therapy: A Delphi study.
Liddell, Alice E; Allan, Steven; Goss, Ken
2017-06-01
Compassion-focused therapy (CFT) has shown promising results for a range of clinical presentations. This study explored the therapeutic competencies required to deliver CFT and organized these into a coherent framework. The Delphi method was used to explore and refine competencies for delivering CFT in three rounds of data collection. The first round involved interviews with 12 experts in CFT. Data were analysed using template analysis to generate a draft competency framework. The main competencies were used to create a survey for rounds two and three involving CFT experts and practitioners. Data collected from the surveys were used to refine the competencies. The CFT competency framework (CFT-CF) that was produced comprised 25 main competencies within six key areas of competence. The areas were as follows: competencies in creating safeness, meta-skills, non-phase-specific skills, phase-specific skills, knowledge and understanding and use of supervision. The main competencies included several subcompetencies specifying knowledge, skills and attributes needed to demonstrate the main competence. Overall, there was consensus on 14 competencies and 20 competencies exceeded an 80% agreement level. Some of the CFT competencies overlapped with existing therapies, whilst others were specific to CFT. The CFT-CF provides useful guidance for clinicians, supervisors and training programmes. Further research could develop the CFT-CF into a therapist rating scale in order to measure the outcome of training and to assess treatment fidelity in clinical trials. The compassion-focused therapy competency framework (CFT-CF) identifies therapeutic competencies that overlap with existing treatments as well as those specific to compassion-focused therapy (CFT). The CFT-CF builds guidance for the competencies required to deliver CFT in a range of clinical settings. The CFT-CF provides guidance for those training CFT therapists. The CFT-CF could be used as a basis to develop a therapist rating scale. © 2016 The British Psychological Society.
Low Resolution Picture Transmission (LRPT) Demonstration System. Phase II; 1.0
NASA Technical Reports Server (NTRS)
Fong, Wai; Yeh, Pen-Shu; Duran, Steve; Sank, Victor; Nyugen, Xuan; Xia, Wei; Day, John H. (Technical Monitor)
2002-01-01
Low-Resolution Picture Transmission (LRPT) is a proposed standard for direct broadcast transmission of satellite weather images. This standard is a joint effort by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) and NOAA. As a digital transmission scheme, its purpose is to replace the current analog Automatic Picture Transmission (APT) system for use in the Meteorological Operational (METOP) satellites. GSFC has been tasked to build an LRPT Demonstration System (LDS). Its main objective is to develop or demonstrate the feasibility of a low-cost receiver utilizing a PC as the primary processing component and determine the performance of the protocol in the simulated Radio Frequency (RF) environment. The approach would consist of two phases.
[Determination of sennosides and degraded products in the process of sennoside metabolism by HPLC].
Sun, Yan; Li, Xuetuo; Yu, Xingju
2004-01-01
A method for the separation and determination of sennosides A and B and the main composition (sennidins A and B) in degraded products of sennosides by linear gradient high performance liquid chromatography has been developed. Separation conditions were as follows: column, a Spherisorb C18 column (250 mm x 4.6 mm i.d., 10 microm); column temperature, 40 degrees C; detection wavelength, 360 nm; mobile phase A, 1.25% acetic acid aqueous solution; mobile phase B, methanol; linear gradient, 100% A --> (20 min) 100% B. The method is effective, quick, accurate and reproducible. The satisfactory results show that this new method has certain practical values as an approach of real-time analysis in the process of sennoside metabolism.
LUNA: low-flying UAV-based forest monitoring system
NASA Astrophysics Data System (ADS)
Keizer, Jan Jacob; Pereira, Luísa; Pinto, Glória; Alves, Artur; Barros, Antonio; Boogert, Frans-Joost; Cambra, Sílvia; de Jesus, Cláudia; Frankenbach, Silja; Mesquita, Raquel; Serôdio, João; Martins, José; Almendra, Ricardo
2015-04-01
The LUNA project is aiming to develop an information system for precision forestry and, in particular, the monitoring of eucalypt plantations that is first and foremost based on multi-spectral imagery acquired using low-flying uav's. The presentation will focus on the first phase of image acquisition, processing and analysis for a series of pot experiments addressing main threats for early-stage eucalypt plantations in Portugal, i.e. acute , chronic and cyclic hydric stress, nutrient stress, fungal infections and insect plague attacks. The imaging results will be compared with spectroscopic measurements as well as with eco-physiological and plant morphological measurements. Furthermore, the presentation will show initial results of the project's second phase, comprising field tests in existing eucalypt plantations in north-central Portugal.
NASA Astrophysics Data System (ADS)
Ito, S.; Takaku, Y.; Ikeda, M.; Kishimoto, Y.
2018-01-01
The Super Kamiokand-Gadolinium (SK-Gd) project is the upgrade of the Super-Kamiokande (SK) detector in order to discover Supernova Relic Neutrinos (SRNs) by loading 0.2% of Gd2(SO4)3 into a 50 kton of the SK water tank. In order to continue solar neutrino measurement with low energy threshold at ˜3.5 MeV, main radioactive contamination, U and Th in Gd2(SO4)3, should be purified before loading. We developed solid-phase extraction technique to measure low concentration of U and Th in Gd2(SO4)3 by ICP-MS. The extraction technique and current status will be presented.
All electrical propagating spin wave spectroscopy with broadband wavevector capability
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ciubotaru, F., E-mail: Florin.Ciubotaru@imec.be; KU Leuven, Departement Electrotechniek; Devolder, T.
2016-07-04
We developed an all electrical experiment to perform the broadband phase-resolved spectroscopy of propagating spin waves in micrometer sized thin magnetic stripes. The magnetostatic surface spin waves are excited and detected by scaled down to 125 nm wide inductive antennas, which award ultra broadband wavevector capability. The wavevector selection can be done by applying an excitation frequency above the ferromagnetic resonance. Wavevector demultiplexing is done at the spin wave detector thanks to the rotation of the spin wave phase upon propagation. A simple model accounts for the main features of the apparatus transfer functions. Our approach opens an avenue for themore » all electrical study of wavevector-dependent spin wave properties including dispersion spectra or non-reciprocal propagation.« less
Multi-Modal Traveler Information System - Gateway Phased Implementation Plan
DOT National Transportation Integrated Search
1997-11-25
The purpose of this working paper is to provide the main concepts and elements that need to be addressed in the overall implementation of the Gateway, both the Initial Phase and the Ultimate Phase. This working paper addresses these concepts and elem...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kulawik, K., E-mail: kulawik@agh.edu.pl; Buffat, P.A., E-mail: philippe.buffat@epfl.ch; Ecole Polytechnique Fédérale de Lausanne, CIME, Station 12, CH-1015 Lausanne Switzerland
Microstructural characterization of Inconel 718 superalloy after three different heat treatment variants was performed by electron microscopy and electron tomography techniques, taking advantage of recent development in quantitative electron microscopy. Distribution maps of the chemical elements, collected by ChemiSTEM™ EDX system, offer a clear contrast between γ′, γ″, and the γ matrix. It was found that the γ′ phase contains mainly Ni, Al, and Ti, while the γ″ phase contains Ni, Nb, and Ti. Thus application of the Al and Nb STEM–EDX elemental maps enables identification and size measurements of γ′ and γ″ nanoparticles. 3D morphology of γ′ and γ″more » precipitates was examined by electron microscopy and FIB–SEM tomography. Employed methods revealed that in all three heat treatment variants the γ′ particles are almost spheroidal while the γ″ precipitates are mainly elongated-disc shaped. However, the precipitate sizes differed for each variant contributing to differences in the yield strength. Tomographic images were used for estimation of the volume fraction of the both strengthening phases. - Highlights: • ChemiSTEM™ EDX elemental maps bring a fast mean to differentiate γ′ and γ″ particles. • Such maps enable for the explicit size measurements of γ′ and γ″ nanoparticles. • Explicit γ′ and γ″ phases total volume fraction was measured employing FIB–SEM. • γ′/γ″ co-precipitates and sandwich-like γ′/γ″/γ′ particles were present. • HRSTEM-HAADF imaging revealed atomic columns of the γ′/γ″ co-precipitates.« less
Left atrium function by 2D speckle tracking in aortic valve disease.
Salas-Pacheco, Jose L; Ávila-Vanzzini, Nydia; Eugenia, Ruiz-Esparza M; Arias-Godínez, Jose A
2016-12-01
A paucity of data exists about left atrium (LA) function in aortic valve stenosis (AS) or regurgitation (AR). Two-dimensional speckle tracking echocardiography allows the noninvasive study of LA functional disturbances in aortic valve disease and their impact in the development of pulmonary hypertension (PH). Consecutive patients with moderate or severe AS or AR were included. Left ventricle (LV) and LA speckle tracking strain quantification was performed. We included 42 patients with AS and 30 with AR. Differences were not found in LA volumes and strain in AS or AR. The LA volumetric derangements parallel the decrease in LA longitudinal strain. Maximum LA volume, minimum LA volume, and indexed LA volume were higher in severe valvular disease (SVD) than in moderate [23 cc (P=.018, IC 95% : 4-41), 16 cc (P=.035, IC 95% : 2-31), and 14 cc (P=.022, IC 95% : 2-25), respectively], occurred in the same way with LA strain in the conduit (6.3%, P=.034, IC 95% : 1-12) and reservoir (7.1%, P=.04, IC 95% : 2-14) phases. In multivariable model, strain of reservoir phase was the variable mainly associated with PH; each decrease in one unit of strain of reservoir phase increased 6% the PH probability (OR: 1.06, P=.01). This study demonstrates that in patients with AS and AR, the LA has a similar behavior and that exist a close correlation between LA volumetric and functional parameters. The variable mainly associated with PH was LA strain of reservoir phase. © 2016, Wiley Periodicals, Inc.
Single phase two pole/six pole motor
Kirschbaum, H.S.
1984-09-25
A single phase alternating current two pole/six pole motor is provided with a main stator winding having six coils disposed unequally around the periphery of the machine. These coils are divided into two groups. When these groups are connected such that their magnetomotive forces are additive, two pole motor operation results. When the polarity of one of the groups is then reversed, six pole motor operation results. An auxiliary stator winding which is similar to the main stator winding is displaced from the main stator winding by 90 electrical degrees on a two pole basis. 12 figs.
IMPROVED TUBULARS FOR BETTER ECONOMICS IN DEEP GAS WELL DRILLING USING MICROWAVE TECHNOLOGY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinesh Agrawal; Paul Gigl; Mahlon Dennis
2005-03-01
The main objective of the research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Originally, it was proposed to accomplish this by developing an efficient and economically viable continuous microwave process to sinter continuously formed/extruded steel powder for the manufacture of seamless coiled tubing and other tubular products. However, based on the results and faced with insurmountable difficulties in the extrusion and de-waxing processes,more » the approach of achieving the goals of the program has been slightly changed. In the continuation proposal an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joining (by induction or microwave) is adopted. This process can be developed into a semi-continuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. Originally, the entire program was spread over three phases with the following goals: Phase I: Demonstration of the feasibility concept of continuous microwave sintering process for tubular steel products. Phase II: Design, building and testing of a prototype microwave system which shall be combined with a continuous extruder for steel tubular objects. Phase III: Execution of the plan for commercialization of the technology by one of the industrial partners. However, since some of the goals of the phase I were not completed, an extension of nine months was granted and we continued extrusion experiments, designed and built semicontinuous microwave sintering unit.« less
The Evolution of Second-Phase Particles in 6111 Aluminum Alloy Processed by Hot and Cold Rolling
NASA Astrophysics Data System (ADS)
Zhang, Lixin; Wang, Yihan; Ni, Song; Chen, Gang; Li, Kai; Du, Yong; Song, Min
2018-03-01
The evolution of coarse Al9.9Fe2.65Ni1.45 phase, spherical Al12(Mn,Fe)3Si phase and rod-like Q phase in a 6111 aluminum alloy during hot and cold rolling deformation processes was systematically investigated in this work. The results showed that the coarse Al9.9Fe2.65Ni1.45 particles are mainly distributed at the grain boundaries, accompanied by the co-formation of Al12(Fe,Mn)3Si phase and Mg2Si phase, while the spherical Al12(Mn,Fe)3Si particles are mainly distributed in the grain interiors. Hot rolling has little effects on the size and distribution of both phases, but cold deformation can severely decrease the size of the particles by breaking the particles into small pieces. In addition, the temperature of 450 °C is not high enough for the dissolution of Q phase in the Al matrix, but the Q particles can be broken into small pieces due to the stress concentration during both hot and cold rolling deformation. In addition, the influences of phase evolution, dislocations and recrystallization on the mechanical properties evolution were also discussed.
Harris, Ricci; Cormack, Donna; Curtis, Elana; Jones, Rhys; Stanley, James; Lacey, Cameron
2016-07-11
Health provider racial/ethnic bias and its relationship to clinical decision-making is an emerging area of research focus in understanding and addressing ethnic health inequities. Examining potential racial/ethnic bias among medical students may provide important information to inform medical education and training. This paper describes the development, pretesting and piloting of study content, tools and processes for an online study of racial/ethnic bias (comparing Māori and New Zealand European) and clinical decision-making among final year medical students in New Zealand (NZ). The study was developed, pretested and piloted using a staged process (eight stages within five phases). Phase 1 included three stages: 1) scoping and conceptual framework development; 2) literature review and identification of potential measures and items; and, 3) development and adaptation of study content. Three main components were identified to assess different aspects of racial/ethnic bias: (1) implicit racial/ethnic bias using NZ-specific Implicit Association Tests (IATs); (2) explicit racial/ethnic bias using direct questions; and, (3) clinical decision-making, using chronic disease vignettes. Phase 2 (stage 4) comprised expert review and refinement. Formal pretesting (Phase 3) included construct testing using sorting and rating tasks (stage 5) and cognitive interviewing (stage 6). Phase 4 (stage 7) involved content revision and building of the web-based study, followed by pilot testing in Phase 5 (stage 8). Materials identified for potential inclusion performed well in construct testing among six participants. This assisted in the prioritisation and selection of measures that worked best in the New Zealand context and aligned with constructs of interest. Findings from the cognitive interviewing (nine participants) on the clarity, meaning, and acceptability of measures led to changes in the final wording of items and ordering of questions. Piloting (18 participants) confirmed the overall functionality of the web-based questionnaire, with a few minor revisions made to the final study. Robust processes are required in the development of study content to assess racial/ethnic bias in order to optimise the validity of specific measures, ensure acceptability and minimise potential problems. This paper has utility for other researchers in this area by informing potential development approaches and identifying possible measurement tools.
Rothgangel, Andreas; Braun, Susy; de Witte, Luc; Beurskens, Anna; Smeets, Rob
2016-04-01
To describe the development and content of a clinical framework for mirror therapy (MT) in patients with phantom limb pain (PLP) following amputation. Based on an a priori formulated theoretical model, 3 sources of data collection were used to develop the clinical framework. First, a review of the literature took place on important clinical aspects and the evidence on the effectiveness of MT in patients with phantom limb pain. In addition, questionnaires and semi-structured interviews were used to analyze clinical experiences and preferences of physical and occupational therapists and patients suffering from PLP regarding the application of MT. All data were finally clustered into main and subcategories and were used to complement and refine the theoretical model. For every main category of the a priori formulated theoretical model, several subcategories emerged from the literature search, patient, and therapist interviews. Based on these categories, we developed a clinical flowchart that incorporates the main and subcategories in a logical way according to the phases in methodical intervention defined by the Royal Dutch Society for Physical Therapy. In addition, we developed a comprehensive booklet that illustrates the individual steps of the clinical flowchart. In this study, a structured clinical framework for the application of MT in patients with PLP was developed. This framework is currently being tested for its effectiveness in a multicenter randomized controlled trial. © 2015 World Institute of Pain.
Evaluating the operational risks of biomedical waste using failure mode and effects analysis.
Chen, Ying-Chu; Tsai, Pei-Yi
2017-06-01
The potential problems and risks of biomedical waste generation have become increasingly apparent in recent years. This study applied a failure mode and effects analysis to evaluate the operational problems and risks of biomedical waste. The microbiological contamination of biomedical waste seldom receives the attention of researchers. In this study, the biomedical waste lifecycle was divided into seven processes: Production, classification, packaging, sterilisation, weighing, storage, and transportation. Twenty main failure modes were identified in these phases and risks were assessed based on their risk priority numbers. The failure modes in the production phase accounted for the highest proportion of the risk priority number score (27.7%). In the packaging phase, the failure mode 'sharp articles not placed in solid containers' had the highest risk priority number score, mainly owing to its high severity rating. The sterilisation process is the main difference in the treatment of infectious and non-infectious biomedical waste. The failure modes in the sterilisation phase were mainly owing to human factors (mostly related to operators). This study increases the understanding of the potential problems and risks associated with biomedical waste, thereby increasing awareness of how to improve the management of biomedical waste to better protect workers, the public, and the environment.
Micropropagation and cryopreservation of garlic (Allium sativum L.).
Keller, E R Joachim; Senula, Angelika
2013-01-01
Garlic (Allium sativum L.) is a very important medicinal and spice plant. It is conventionally propagated by daughter bulbs ("cloves") and bulbils from the flower head. Micropropagation is used for speeding up the vegetative propagation mainly using the advantage to produce higher numbers of healthy plants free of viruses, which have higher yield than infected material. Using primary explants from bulbs and/or bulbils (shoot tips) or unripe inflorescence bases, in vitro cultures are initiated on MS-based media containing auxins, e.g., naphthalene acetic acid, and cytokinins, e.g., 6-γ-γ-(dimethylallylaminopurine) (2iP). Rooting is accompanying leaf formation. It does not need special culture phases. The main micropropagation methods rely on growth of already formed meristems. Long-term storage of micropropagated material, cryopreservation, is well-developed to maintain germplasm. The main method is vitrification using the cryoprotectant mixture PVS3.
Stevenson, Edward G. J.; Greene, Leslie E.; Maes, Kenneth C.; Ambelu, Argaw; Tesfaye, Yihenew Alemu; Rheingans, Richard; Hadley, Craig
2012-01-01
Water insecurity is a primary underlying determinant of global health disparities. While public health research on water insecurity has focused mainly on two dimensions, water access and adequacy, an anthropological perspective highlights the cultural or lifestyle dimension of water insecurity, and its implications for access / adequacy and for the phenomenology of water insecurity. Recent work in Bolivia has shown that scores on a water insecurity scale derived from ethnographic observations are associated with emotional distress. We extend this line of research by assessing the utility of a locally developed water insecurity scale, compared with standard measures of water access and adequacy, in predicting women's psychosocial distress in Ethiopia. In 2009-2010 we conducted two phases of research. Phase I was mainly qualitative and designed to identify locally relevant experiences of water insecurity, and Phase II used a quantitative survey to test the association between women's reported water insecurity and the Falk Self-Reporting Questionnaire (SRQ-F), a measure of psychosocial distress. In multiple regression models controlling for food insecurity and reported quantity of water used, women's water insecurity scores were significantly associated with psychosocial distress. Including controls for time required to collect water and whether water sources were protected did not further predict psychosocial distress. This approach highlights the social dimension of water insecurity, and may be useful for informing and evaluating interventions to improve water supplies. PMID:22575697
The role of nano-particles in the field of thermal spray coating technology
NASA Astrophysics Data System (ADS)
Siegmann, Stephan; Leparoux, Marc; Rohr, Lukas
2005-06-01
Nano-particles play not only a key role in recent research fields, but also in the public discussions about health and safety in nanotechnology. Nevertheless, the worldwide activities in nano-particles research increased dramatically during the last 5 to 10 years. There are different potential routes for the future production of nano-particles at large scale. The main directions envisaged are mechanical milling, wet chemical reactions or gas phase processes. Each of the processes has its specific advantages and limitations. Mechanical milling and wet chemical reactions are typically time intensive and batch processes, whereas gas phase productions by flames or plasma can be carried out continuously. Materials of interest are mainly oxide ceramics, carbides, nitrides, and pure metals. Nano-ceramics are interesting candidates for coating technologies due to expected higher coating toughness, better thermal shock and wear resistance. Especially embedded nano-carbides and-nitrides offer homogenously distributed hard phases, which enhance coatings hardness. Thermal spraying, a nearly 100 years old and world wide established coating technology, gets new possibilities thanks to optimized, nano-sized and/or nano-structured powders. Latest coating system developments like high velocity flame spraying (HVOF), cold gas deposition or liquid suspension spraying in combination with new powder qualities may open new applications and markets. This article gives an overview on the latest activities in nano-particle research and production in special relation to thermal spray coating technology.
High pressure phase transformations revisited
NASA Astrophysics Data System (ADS)
Levitas, Valery I.
2018-04-01
High pressure phase transformations play an important role in the search for new materials and material synthesis, as well as in geophysics. However, they are poorly characterized, and phase transformation pressure and pressure hysteresis vary drastically in experiments of different researchers, with different pressure transmitting media, and with different material suppliers. Here we review the current state, challenges in studying phase transformations under high pressure, and the possible ways in overcoming the challenges. This field is critically compared with fields of phase transformations under normal pressure in steels and shape memory alloys, as well as plastic deformation of materials. The main reason for the above mentioned discrepancy is the lack of understanding that there is a fundamental difference between pressure-induced transformations under hydrostatic conditions, stress-induced transformations under nonhydrostatic conditions below yield, and strain-induced transformations during plastic flow. Each of these types of transformations has different mechanisms and requires a completely different thermodynamic and kinetic description and experimental characterization. In comparison with other fields the following challenges are indicated for high pressure phase transformation: (a) initial and evolving microstructure is not included in characterization of transformations; (b) continuum theory is poorly developed; (c) heterogeneous stress and strain fields in experiments are not determined, which leads to confusing material transformational properties with a system behavior. Some ways to advance the field of high pressure phase transformations are suggested. The key points are: (a) to take into account plastic deformations and microstructure evolution during transformations; (b) to formulate phase transformation criteria and kinetic equations in terms of stress and plastic strain tensors (instead of pressure alone); (c) to develop multiscale continuum theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.
High pressure phase transformations revisited.
Levitas, Valery I
2018-04-25
High pressure phase transformations play an important role in the search for new materials and material synthesis, as well as in geophysics. However, they are poorly characterized, and phase transformation pressure and pressure hysteresis vary drastically in experiments of different researchers, with different pressure transmitting media, and with different material suppliers. Here we review the current state, challenges in studying phase transformations under high pressure, and the possible ways in overcoming the challenges. This field is critically compared with fields of phase transformations under normal pressure in steels and shape memory alloys, as well as plastic deformation of materials. The main reason for the above mentioned discrepancy is the lack of understanding that there is a fundamental difference between pressure-induced transformations under hydrostatic conditions, stress-induced transformations under nonhydrostatic conditions below yield, and strain-induced transformations during plastic flow. Each of these types of transformations has different mechanisms and requires a completely different thermodynamic and kinetic description and experimental characterization. In comparison with other fields the following challenges are indicated for high pressure phase transformation: (a) initial and evolving microstructure is not included in characterization of transformations; (b) continuum theory is poorly developed; (c) heterogeneous stress and strain fields in experiments are not determined, which leads to confusing material transformational properties with a system behavior. Some ways to advance the field of high pressure phase transformations are suggested. The key points are: (a) to take into account plastic deformations and microstructure evolution during transformations; (b) to formulate phase transformation criteria and kinetic equations in terms of stress and plastic strain tensors (instead of pressure alone); (c) to develop multiscale continuum theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.
Electromechanical modelling and design for phase control of locked modes in the DIII-D tokamak
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olofsson, K. E. J.; Choi, W.; Humphreys, D. A.
A basic nonlinear electromechanical model is developed for the interaction between a pre-existing near-saturated tearing-mode, a conducting wall, active coils internal to the wall, and active coils external to the wall. The tearing-mode is represented by a perturbed helical surface current and its island has a small but finite moment of inertia. The model is shown to have several properties that are qualitatively consistent with the experimental observations of mode-wall and mode-coil interactions. The main purpose of the model is to guide the design of a phase control system for locked modes (LMs) in tokamaks. Such a phase controller maymore » become an important component in integrated disruption avoidance systems. A realistic feedback controller for the LM phase is designed and tested for the electromechanical model. The results indicate that a simple fixed-gain controller can perform phase control of LMs with a range of sizes, and at arbitrary misalignment relative to a realistically dimensioned background error field. Finally, the basic model is expected to be a useful minimal dynamical system representation also for other aspects of mode-wall-coil interactions.« less
NASA Astrophysics Data System (ADS)
Korolkov, Victor P.; Konchenko, Alexander S.; Cherkashin, Vadim V.; Mironnikov, Nikolay G.; Poleshchuk, Alexander G.
2013-09-01
Detailed analysis of etch depth map for phase binary computer-generated holograms intended for testing aspheric optics is a very important task. In particular, diffractive Fizeau null lenses need to be carefully tested for uniformity of etch depth. We offer a simplified version of the specular spectroscopic scatterometry method. It is based on the spectral properties of binary phase multi-order gratings. An intensity of zero order is a periodical function of illumination light wave number. The grating grooves depth can be calculated as it is inversely proportional to the period. Measurement in reflection allows one to increase the phase depth of the grooves by a factor of 2 and measure more precisely shallow phase gratings. Measurement uncertainty is mainly defined by the following parameters: shifts of the spectrum maximums that occur due to the tilted grooves sidewalls, uncertainty of light incidence angle measurement, and spectrophotometer wavelength error. It is theoretically and experimentally shown that the method we describe can ensure 1% error. However, fiber spectrometers are more convenient for scanning measurements of large area computer-generated holograms. Our experimental system for characterization of binary computer-generated holograms was developed using a fiber spectrometer.
Intermetallic Compound Growth and Stress Development in Al-Cu Diffusion Couple
NASA Astrophysics Data System (ADS)
Mishler, M.; Ouvarov-Bancalero, V.; Chae, Seung H.; Nguyen, Luu; Kim, Choong-Un
2018-01-01
This paper reports experimental observations evidencing that the intermetallic compound phase interfaced with Cu in the Al-Cu diffusion couple is most likely α2-Cu3Al phase, not γ-Cu9Al4 phase as previously assumed, and that its growth to a critical thickness may result in interface failure by stress-driven fracture. These conclusions are made based on an interdiffusion study of a diffusion couple made of a thick Cu plate coated with ˜ 2- μm-thick Al thin film. The interface microstructure and lattice parameter were characterized using scanning electron microscopy and x-ray diffraction analysis. Specimens aged at temperature between 623 K (350°C) and 723 K (450°C) for various hours produced consistent results supporting the main conclusions. It is found that disordered α2-Cu3Al phase grows in a similar manner to solid-state epitaxy, probably owing to its structural similarity to the Cu lattice. The increase in the interface strain that accompanies the α2-Cu3Al phase growth ultimately leads to interface fracture proceeding from crack initiation and growth along the interface. This mechanism provides the most consistent explanation for interface failures observed in other studies.
Zhai, Xingchen; Zhao, Haitian; Zhang, Min; Yang, Xin; Sun, Jingming; She, Yongxin; Dong, Aijun; Zhang, Hua; Yao, Lei; Wang, Jing
2018-04-01
A new 3‑aminophenylboronic acid-functionalized stationary phase based on silica for hydrophilic interaction liquid chromatography (HILIC) was developed and showed great HILIC characteristics on separation for chito‑oligosaccharides. The material was synthesized by grafting 3‑aminophenylboronic acid group to silica, and it was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), elemental analysis and thermal gravimetric analysis (TGA). Nucleobases and nucleosides were used to evaluate the retention property and to investigate retention mechanism by the models designed for description of partitioning and surface adsorption through adjusting ratio of water in the mobile phase. Parameters affecting chromatography behavior such as ionic strength, buffer pH and column temperature were also investigated. Results have indicated that the retention mechanism was a combination of partitioning and surface adsorption, and the hydrogen bond seemed to be the main force for the retention behavior. Finally, the new 3‑aminophenylboronic acid-functionalized based on silica stationary phase was applied to separate chito-oligosaccharide samples with optimized mobile phase conditions and showed acceptable chromatograms. Copyright © 2018 Elsevier B.V. All rights reserved.
Towards the control of the modal energy transfer in transverse mode instabilities
NASA Astrophysics Data System (ADS)
Stihler, Christoph; Jauregui, Cesar; Tünnermann, Andreas; Limpert, Jens
2018-02-01
Thermally-induced refractive index gratings (RIG) in high-power fiber laser systems lead to transverse mode instabilities (TMI) above a certain average power threshold. The effect of TMI is currently the main limitation for the further average power scaling of fiber lasers and amplifiers with nearly diffraction-limited beam quality. In this work we experimentally investigate, for the first time, the growth of the RIG strength by introducing a phase-shift between the RIG and the modal interference pattern in a fiber amplifier. The experiments reveal that the RIG is strong enough to couple energy between different transverse modes even at powers significantly below the TMI threshold, provided that the introduced phase-shift is high enough. This indicates that, as the strength of the RIG further increases with increasing average output power, the RIG becomes more and more sensitive to even small noise-induced phase-shifts, which ultimately trigger TMI. Furthermore, it is shown that a beam cleaning also occurs when a positive phase-shift is introduced, even above the TMI threshold. This finding will pave the way for the development of a new class of mitigation strategies for TMI, which key feature is the control of the introduced phase-shift.