Science.gov

Sample records for pin power reconstruction

  1. SIMULATE-4 pin power calculations

    SciTech Connect

    Bahadir, T.; Lindahl, S. Oe

    2006-07-01

    A new pin power reconstruction module has been implemented in Studsvik Scandpower's next generation nodal code, SIMULATE-4. Heterogeneous pin powers are calculated by modulating multi-group pin powers from the sub-mesh solver of SIMULATE-4 with pin form factors from single-assembly CASMO-5 lattice calculations. The multi-group pin power model captures instantaneous spectral effects, and actinide tracking on the assembly sub-mesh describes exposure-induced pin power variations. Model details and verification tests against high order multi-assembly transport methods are presented. The accuracy of the new methods is also demonstrated by comparing SIMULATE-4 calculations with measured critical experiment pin powers. (authors)

  2. Pinning Loss Power Density in Superconductors

    NASA Astrophysics Data System (ADS)

    Matsushita, Teruo

    2015-03-01

    The pinning loss power density is theoretically derived based on the resistive energy dissipation when the flux lines are driven by the Lorentz force in a superconductor. The obtained loss power density does not depend on the viscosity or flow resistivity, but is proportional to the pinning force density only, and it possesses the nature of hysteresis loss, as commonly measured in experiments. These features are predicted by the critical state model, which was recently proved theoretically. The obtained pinning force density is consistent with the prediction of the coherent potential approximation theory, a kind of statistical summation theory, for flux pinning. Thus, the irreversible properties associated with the flux pinning can be comprehensively described by these flux pinning theories. The irreversible flux pinning in the superconductor is compared with similar irreversible phenomena such as the motion of magnetic domain walls in ferromagnetic materials and the friction in mechanical systems. The possibility is also discussed for a general theoretical description of these irreversible phenomena in which the hysteresis loss occurs.

  3. A complication following ACL reconstruction using bioabsorbable cross-pins.

    PubMed

    Vecchini, Eugenio; Micheloni, Gian Mario; Corbo, Valentina Rita; Perusi, Francesco; Dib, Giovanni; Magnan, Bruno

    2016-01-01

    This is a case of a proximal pin migration after ACL reconstruction in medial soft tissue with pain, inflammatory reaction and functional reduction. 33-year-old male presented at our clinic with a complete ACL rupture. Reconstruction with autogenous gracilis and semitendinosus hamstring tendons was performed and graft fixed in the femoral canal with two PLLA bioabsorbable pins (RIGIDFIX® Cross Pin System). Two months postoperatively the patient presented swelling and pain on the medial side of the knee, full range of motion and negative results at the Lachman and Pivot shift tests. MRI examination showed the superior femoral tunnel crossing both the lateral and medial cortex lodging the pin in the knee's medial soft tissue corresponding to the swelling area reported by the patient. The tendon graft was properly positioned. After surgical removal of the pin through a small skin incision, the pain and swelling promptly subsided allowing the patient return to normal activities in few weeks without any pain. In our opinion the painful swelling of the knee was due to a displacement of the pin that had been accidentally lodged in the soft tissues instead of the bone causing a foreign-body reaction resulting in granuloma formation with local inflammation. This dislodgement could have been due to an inappropriately long femoral tunnel. PMID:27104331

  4. Pin guidance of reconstruction plate contour: an expanded role of external fixation.

    PubMed

    Jaquet, Yves; Higgins, Kevin M; Enepekides, Danny J

    2011-09-01

    This article presents a modification of intraoperative external fixation for mandibular reconstruction with free tissue flaps. This technique is indicated when preregistration of the reconstruction plate is not possible due to transmandibular tumor extension. Once standard external fixation has been carried out and prior to segmental mandibulectomy, additional pins are fixed to the connecting rod that delineate the mandibular contour in three-dimensional (3D) space. Following mandibulectomy, these pins allow accurate contouring of the reconstruction plate and improved restoration of mandibular contour, projection, and dental occlusion. A step-by-step description of the technique using models and intraoperative photos is presented. This method of mandibular reconstruction is a simple and time-effective alternative to intraoperative computer navigation and 3D modeling in select cases of oral carcinoma where tumor infiltration of the outer mandibular cortex precludes prebending of the reconstruction plates. PMID:22024840

  5. Evaluation of rodded BWR assembly pin powers with simulate

    SciTech Connect

    Bahadir, T.; Lindahl, S. Oe.

    2012-07-01

    In the development of Studsvik's nodal code SIMULATE5, special attention has been given to the accurate description of pin powers. The code solves the multi-group diffusion or simplified P3 equations with high spatial resolution. A short description is given of the handling of material heterogeneities in the axial and radial directions - the axial re-homogenization and the radial sub-mesh model, respectively. Furthermore, two models which are of special importance in the presence of control rods, and hence on the pellet clad interaction (PCI) phenomenon, are described; the quarter-assembly thermal-hydraulic treatment and the depletion of absorber material. A numerical example for a real core shows that while the impact of the fine grained description is negligible on global parameters such as k{sub eff}, the effect on pin powers may be substantial. For a deeply inserted and highly depleted control rod, the difference in pin powers caused by neglecting the advanced models of SIMULATE5, may be as high as 15 %. (authors)

  6. Diffusion-limited aggregation with power-law pinning.

    PubMed

    Hentschel, H G E; Popescu, M N; Family, F

    2004-01-01

    Using stochastic conformal mapping techniques we study the patterns emerging from Laplacian growth with a power-law decaying threshold for growth R(-gamma)(N) (where R(N) is the radius of the N-particle cluster). For gamma>1 the growth pattern is in the same universality class as diffusion limited aggregation (DLA), while for gamma<1 the resulting patterns have a lower fractal dimension D(gamma) than a DLA cluster due to the enhancement of growth at the hot tips of the developing pattern. Our results indicate that a pinning transition occurs at gamma=1/2, significantly smaller than might be expected from the lower bound alpha(min) approximately 0.67 of multifractal spectrum of DLA. This limiting case shows that the most singular tips in the pruned cluster now correspond to those expected for a purely one-dimensional line. Using multifractal analysis, analytic expressions are established for D(gamma) both close to the breakdown of DLA universality class, i.e., gamma less, similar 1, and close to the pinning transition, i.e., gamma greater, similar 1/2. PMID:14995617

  7. A wirelessly powered microspectrometer for neural probe-pin device

    NASA Astrophysics Data System (ADS)

    Choi, Sang H.; Kim, Min H.; Song, Kyo D.; Yoon, Hargsoon; Lee, Uhn

    2015-12-01

    Treatment of neurological anomalies, whether done invasively or not, places stringent demands on device functionality and size. We have developed a micro-spectrometer for use as an implantable neural probe to monitor neuro-chemistry in synapses. The micro-spectrometer, based on a NASA-invented miniature Fresnel grating, is capable of differentiating the emission spectra from various brain tissues. The micro-spectrometer meets the size requirements, and is able to probe the neuro-chemistry and suppression voltage typically associated with a neural anomaly. This neural probe-pin device (PPD) is equipped with wireless power technology (WPT) to enable operation in a continuous manner without requiring an implanted battery. The implanted neural PPD, together with a neural electronics interface and WPT, enable real-time measurement and control/feedback for remediation of neural anomalies. The design and performance of the combined PPD/WPT device for monitoring dopamine in a rat brain will be presented to demonstrate the current level of development. Future work on this device will involve the addition of an embedded expert system capable of performing semi-autonomous management of neural functions through a routine of sensing, processing, and control.

  8. Holding power of three different pin designs in the femur and ulna of the common buzzard (Buteo buteo).

    PubMed

    López García, Mariano; López Beceiro, Ana M; Valcárcel Juárez, Víctor; Muñoz Guzón, Fernando; González Cantalapiedra, Antonio

    2011-12-01

    External skeletal fixation is generally considered the best stabilization technique for immobilizing avian long bone fractures, but one of its major complications is the failure of bone-fixation pin interface or the loss of holding power. Consequently, this study is aimed at elucidating which pin design offers more pull-out strength in certain bones of the common buzzard (Buteo buteo). To achieve this objective, three pin designs (a smooth design and two negative profile threaded designs, with different thread pitch) were placed in five positions along the femur and ulna of the common buzzard. The pin pull-out strength was measured with the purpose of comparing medullary and pneumatic bones, insertion sites, and pin designs. Threaded pins with negative profile showed greater holding power than smooth pins (P < 0.05). When comparing holding power between the ulna and femur, no differences were found for smooth pins, whereas threaded pins showed more pull-out strength in the ulna than in the femur (P < 0.05). There were no differences observed related to pin location along the same bone when considering the same pin type. These results suggest that negative profile threaded pins have more holding power than smooth pins and that pneumatic bones provide less pull-out strength to negative profile threaded pins than medullary bones. PMID:22204047

  9. Broken bioabsorbable femoral cross-pin as a cause of a chondral lesion after anterior cruciate ligament reconstruction.

    PubMed

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Ziogas, Evangelos; Dimitriadis, Theofilos; Voulgaropoulos, Harilaos

    2009-01-01

    We present a case of a chondral lesion after anterior cruciate ligament (ACL) reconstruction caused by femoral cross-pin breakage and intra-articular migration of the fragment. A 20-year-old man initially underwent ACL reconstruction using a hamstring autograft. The RigidFix bioabsorbable cross-pin (DePuy Mitek) was used for the femoral fixation. The patient returned to a pre-injury level of activity (professional soccer player) 6 months postoperatively. However, 20 months postoperatively, the patient presented with effusion and lateral joint-line pain after practice, without signs of instability in clinical examination. Conservative treatment failed and at re-arthroscopy a chondral lesion of the lateral femoral and tibial condyle was found, which had been caused by the broken femoral cross-pin. The fragment was removed and the symptoms resolved. Orthopaedic surgeons should be aware of this complication when using a bioabsorbable cross-pin for femoral fixation in ACL reconstruction. PMID:21686583

  10. Broken bioabsorbable femoral cross-pin as a cause of a chondral lesion after anterior cruciate ligament reconstruction

    PubMed Central

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Ziogas, Evangelos; Dimitriadis, Theofilos; Voulgaropoulos, Harilaos

    2009-01-01

    We present a case of a chondral lesion after anterior cruciate ligament (ACL) reconstruction caused by femoral cross-pin breakage and intra-articular migration of the fragment. A 20-year-old man initially underwent ACL reconstruction using a hamstring autograft. The RigidFix bioabsorbable cross-pin (DePuy Mitek) was used for the femoral fixation. The patient returned to a pre-injury level of activity (professional soccer player) 6 months postoperatively. However, 20 months postoperatively, the patient presented with effusion and lateral joint-line pain after practice, without signs of instability in clinical examination. Conservative treatment failed and at re-arthroscopy a chondral lesion of the lateral femoral and tibial condyle was found, which had been caused by the broken femoral cross-pin. The fragment was removed and the symptoms resolved. Orthopaedic surgeons should be aware of this complication when using a bioabsorbable cross-pin for femoral fixation in ACL reconstruction. PMID:21686583

  11. Pinning down the Constitution: Interactively Teaching Congress's Power, Federalism, and Constitutional Interpretation

    ERIC Educational Resources Information Center

    Emenaker, Ryan

    2014-01-01

    "Pin-the-Tail-on-the-Constitution" is an engaged-learning activity that has been conducted in 26 classes over the past four years. The activity teaches multiple themes commonly included in a variety of courses on American politics such as federalism, congressional powers, the role of the federal courts, and the relevance of the commerce…

  12. Applying Cross-Pin System in Both Femoral and Tibial Fixation in Anterior Cruciate Ligament Reconstruction Using Hamstring Tendons

    PubMed Central

    Qi, Wei; Liu, Yujie; Xue, Jing; Li, Haifeng; Wang, Junliang; Qu, Feng

    2015-01-01

    Use of the RigidFix Cross Pin System (DePuy Mitek, Raynham, MA) is a popular technique for femoral fixation of grafts in anterior cruciate ligament reconstruction (ACLR). However, tibial fixation is still limited to the use of interference screws and post fixation, and few surgeons apply the femoral RigidFix system in tibial fixation. Meanwhile, tunnel enlargement is still a problem that affects the outcome of ACLR with hamstring grafts. We have used the femoral RigidFix system in femoral and tibial fixation. The rod top of the guide frame should be placed under the level of the subchondral bone at the proximal end of the tibial tunnel to ensure that the pins will not be inserted into the joint. The pins are inserted through the center of the lateral tibia. Using our technique, the fixation points of the femur and tibia are close to the anterior cruciate ligament insertions, and full contact of the graft with the tunnel wall can be accomplished. On the basis of our preliminary observations and investigation, we are optimistic about the prospect of performing ACLR using the RigidFix system in femoral and tibial fixation. PMID:26697293

  13. Sensitivity and System Response of Pin Power Peaking in VVER-1000 Fuel Assembly Using TSUNAMI-2D

    NASA Astrophysics Data System (ADS)

    Frybort, J.

    2014-04-01

    Pin power peaking in a VVER-1000 fuel assembly and its sensitivity and uncertainty was analyzed by TSUNAMI-2D code. Several types of fuel assemblies were considered. They differ in number and position of gadolinium fuel pins. The calculations were repeated for several fuel compositions obtained by fuel depletion calculation. The results are quantified sensitivity data, which can be used for enrichment profiling.

  14. Performance and breakdown characteristics of irradiated vertical power GaN P-i-N diodes

    DOE PAGESBeta

    King, M. P.; Armstrong, A. M.; Dickerson, J. R.; Vizkelethy, G.; Fleming, R. M.; Campbell, J.; Wampler, W. R.; Kizilyalli, I. C.; Bour, D. P.; Aktas, O.; et al

    2015-10-29

    Electrical performance and defect characterization of vertical GaN P-i-N diodes before and after irradiation with 2.5 MeV protons and neutrons is investigated. Devices exhibit increase in specific on-resistance following irradiation with protons and neutrons, indicating displacement damage introduces defects into the p-GaN and n- drift regions of the device that impact on-state device performance. The breakdown voltage of these devices, initially above 1700 V, is observed to decrease only slightly for particle fluence <; 1013 cm-2. Furthermore, the unipolar figure of merit for power devices indicates that while the on-resistance and breakdown voltage degrade with irradiation, vertical GaN P-i-Ns remainmore » superior to the performance of the best available, unirradiated silicon devices and on-par with unirradiated modern SiC-based power devices.« less

  15. Improved designs for p-i-n OLEDs towards the minimal power loss of devices

    NASA Astrophysics Data System (ADS)

    Qin, Dashan

    2014-05-01

    Currently, the low yield, high power loss, and poor stability of organic light emitting diodes (OLEDs) panels are remaining as the obstacles to the fast growth of the OLED industry, especially for the lighting application. The p-i-n OLEDs have been widely recognized as the promising method to circumvent these bottleneck factors, due to the unique merit of the electrical doping to enable low power loss. In p-i-n OLEDs, the frequently used n-doped electron transport layers (n-ETL1) such as n-BCP, n-Alq3 possess markedly lower conductivities but better capabilities of injecting electrons into ETL such as BCP, Alq3, as compared to another class of n-doped ETLs (n-ETL2), e.g., n-NTCDA, n-PTCDA, n-C60. Thus, in order to minimize the electron loss, we provide the structure of uniting two n-doped layers, cathode/ n-ETL2/ n-ETL1/ ETL. In p-i-n OLEDs, the hole current injected from the single p-doped hole transport layer (p-HTL) into the neat HTL must be limited, because the higher conductivity p-HTL has the higher lying highest occupied molecular orbital (HOMO) level, leading to a larger hole transport energy barrier (φB) at the interface with the neat HTL. Therefore, in order to minimize the hole loss, we suggest the structure of uniting two p-HTLs, anode/ p-HTL2/ p-HTL1/ HTL. The p-HTL2 possesses high-lying HOMO level and thereby high conductivity, decreasing the ohmic loss in the hole conduction; the p-HTL1 features a low-lying HOMO level, reducing the φB.

  16. Single-Bundle Anterior Cruciate Ligament Reconstruction with Semitendinosus Tendon Using the PINN-ACL CrossPin System: Minimum 4-Year Follow-up

    PubMed Central

    Baek, Seung-Gil; Lee, Byoung-Joo; Lee, Chang-Hwa

    2015-01-01

    Purpose This study evaluated mid-term results of anterior cruciate ligament (ACL) reconstruction using the PINN-ACL CrossPin system that allowed for short graft fixation. Materials and Methods Forty-three patients underwent single-bundle ACL reconstruction with a 4-strand semitendinosus tendon graft using the PINN-ACL CrossPin system. Femoral fixation was done using the PINN-ACL CrossPin system, and the tibial side was fixed with post-tie and a bioabsorbable interference screw. The mean follow-up period was 50 months. Evaluation was done using the Lachman test, pivot-shift test, International Knee Documentation Committee (IKDC) score and grade. Anterior displacement was assessed. Results There was improvement in the Lachman test and pivot-shift test at final follow-up, form grade II (n=40) or III (n=3) to grade I (n=3) or 0 (n=40) and from grade I (n=20) or II (n=10) to grade I (n=8) or 0 (n=22), respectively. The mean IKDC score was 88.7, and grade A and B were 93.0% at final follow-up. Side-to-side difference was improved from 6.7 mm to 2.1 mm at final follow-up. Complications occurred in 3 patients, a re-ruptured due to trauma at 2 years after surgery and a deep infection and a superficial infection. Conclusions The mid-term follow-up results of ACL reconstruction with the PINN-ACL CrossPin system were satisfactory. The PINN-ACL CrossPin can be considered as a useful instrument for short graft fixation. PMID:25750893

  17. BIOMECHANICAL STUDY OF TRANSCORTICAL OR TRANSTRABECULAR BONE FIXATION OF PATELLAR TENDON GRAFT WITH BIOABSORBABLE PINS IN ACL RECONSTRUCTION IN SHEEP

    PubMed Central

    Albano, Mauro Batista; Borges, Paulo César; Namba, Mario Massatomo; da Silva, João Luiz Vieira; de Assis Pereira Filho, Francisco; Filho, Edmar Stieven; Matias, Jorge Eduardo Fouto

    2015-01-01

    Objective: To determine the initial resistance of fixation using the Rigid Fix® system, and compare it with traditional fixation methods using metal interference screws; and to evaluate the resistance of the fixation with the rigid fix system when the rotational position of the bone block is altered in the interior of the femoral tunnel. Methods: forty ovine knee specimens (stifle joints) were submitted to anterior cruciate ligament reconstruction (ACL) using a bone-tendon-bone graft. In twenty specimens, the Rigid Fix method was used; this group was subdivided into two groups: ten knees the pins transfixed only the spongious area of the bone block, and ten for fixation passing through the layer of cortical bone. In the twenty remaining specimens, the graft was fixed with 9mm metal interference screws. Results: comparison of the RIGIDFIX® method with the metal interference screw fixation method did not show any statistically significant differences in terms of maximum load and rigidity; also, there were no statistically significant differences when the rotational position of the bone block was altered inside the femoral tunnel. For these evaluations, a level of significance of p < 0.017 was considered. Conclusion: fixation of the bone-tendon-bone graft with 2 bioabsorbable pines, regardless of the rotational position inside the femoral tunnel, gave a comparable fixation in terms of initial resistance to the metal interference screw, in this experimental model. PMID:27027081

  18. Use of TRIPOLI-4.3 lattice tally to investigate assembly power and pin power maps of PWR critical lattices experiments

    SciTech Connect

    Lee, Y. K.

    2006-07-01

    Power distribution calculation is a very important task for fuel assembly design and whole core safety analysis. In Monte Carlo power map calculation, both lattice geometry and lattice tally functions are essential. The lattice geometry features of TRIPOLI-4 Monte Carlo code have been reported in previous studies. Lattice tally functions of TRIPOLI-4.3 can be used to tally on some or all cells in a fuel pin lattice and to tally on a fuel assembly lattice with pin-by-pin modeling. In order to study the power maps in pin-by-pin level and in assembly-by-assembly level, this paper using lattice tally of TRIPOLI-4.3 code interprets three PWR critical lattice experiments from LEU-COMP-THERM-008 benchmark. The calculated K{sub eff} and relative assembly power maps in a 3 x 3 symmetry configuration have been investigated. The measured relative pin power distributions of 1/8 central assembly with different effects of lattice heterogeneity have been benchmarked against calculated ones. (authors)

  19. Influence of DBT reconstruction algorithm on power law spectrum coefficient

    NASA Astrophysics Data System (ADS)

    Vancamberg, Laurence; Carton, Ann-Katherine; Abderrahmane, Ilyes H.; Palma, Giovanni; Milioni de Carvalho, Pablo; Iordache, Rǎzvan; Muller, Serge

    2015-03-01

    In breast X-ray images, texture has been characterized by a noise power spectrum (NPS) that has an inverse power-law shape described by its slope β in the log-log domain. It has been suggested that the magnitude of the power-law spectrum coefficient β is related to mass lesion detection performance. We assessed β in reconstructed digital breast tomosynthesis (DBT) images to evaluate its sensitivity to different typical reconstruction algorithms including simple back projection (SBP), filtered back projection (FBP) and a simultaneous iterative reconstruction algorithm (SIRT 30 iterations). Results were further compared to the β coefficient estimated from 2D central DBT projections. The calculations were performed on 31 unilateral clinical DBT data sets and simulated DBT images from 31 anthropomorphic software breast phantoms. Our results show that β highly depends on the reconstruction algorithm; the highest β values were found for SBP, followed by reconstruction with FBP, while the lowest β values were found for SIRT. In contrast to previous studies, we found that β is not always lower in reconstructed DBT slices, compared to 2D projections and this depends on the reconstruction algorithm. All β values estimated in DBT slices reconstructed with SBP were larger than β values from 2D central projections. Our study also shows that the reconstruction algorithm affects the symmetry of the breast texture NPS; the NPS of clinical cases reconstructed with SBP exhibit the highest symmetry, while the NPS of cases reconstructed with SIRT exhibit the highest asymmetry.

  20. Thermal analysis of the FSP-1 fuel pin irradiation test. [for SP-100 space power reactor

    NASA Technical Reports Server (NTRS)

    Lyon, William F., III

    1991-01-01

    Thermal analysis of a pin from the FSP-1 fuels irradiation test has been completed. The purpose of the analysis was to provide predictions of fuel pin temperatures, determine the flow regime within the lithium annulus of the test assembly, and provide a standardized model for a consistent basis of comparison between pins within the test assembly. The calculations have predicted that the pin is operating at slightly above the test design temperatures and that the flow regime within the lithium annulus is a laminar buoyancy driven flow.

  1. Off-design temperature effects on nuclear fuel pins for an advanced space-power-reactor concept

    NASA Technical Reports Server (NTRS)

    Bowles, K. J.

    1974-01-01

    An exploratory out-of-reactor investigation was made of the effects of short-time temperature excursions above the nominal operating temperature of 990 C on the compatibility of advanced nuclear space-power reactor fuel pin materials. This information is required for formulating a reliable reactor safety analysis and designing an emergency core cooling system. Simulated uranium mononitride (UN) fuel pins, clad with tungsten-lined T-111 (Ta-8W-2Hf) showed no compatibility problems after heating for 8 hours at 2400 C. At 2520 C and above, reactions occurred in 1 hour or less. Under these conditions free uranium formed, redistributed, and attacked the cladding.

  2. A novel phylogeny and morphological reconstruction of the PIN genes and first phylogeny of the ACC-oxidases (ACOs)

    PubMed Central

    Clouse, Ronald M.; Carraro, Nicola

    2014-01-01

    The PIN and ACO gene families present interesting questions about the evolution of plant physiology, including testing hypotheses about the ecological drivers of their diversification and whether unrelated genes have been recruited for similar functions. The PIN-formed proteins contribute to the polar transport of auxin, a hormone which regulates plant growth and development. PIN loci are categorized into groups according to their protein length and structure, as well as subcellular localization. An interesting question with PIN genes is the nature of the ancestral form and location. ACOs are members of a superfamily of oxygenases and oxidases that catalyze the last step of ethylene synthesis, which regulates many aspects of the plant life cycle. We used publicly available PIN and ACO sequences to conduct phylogenetic analyses. Third codon positions of these genes in monocots have a high GC content, which could be historical but is more likely due to a mutational bias. Thus, we developed methods to extract phylogenetic information from nucleotide sequences while avoiding this convergent feature. One method consisted in using only A-T transformations, and another used only the first and second codon positions for serine, which can only take A or T and G or C, respectively. We also conducted tree-searches for both gene families using unaligned amino acid sequences and dynamic homology. PIN genes appear to have diversified earlier than ACOs, with monocot and dicot copies more mixed in the phylogeny. However, gymnosperm PINs appear to be derived and not closely related to those from primitive plants. We find strong support for a long PIN gene ancestor with short forms subsequently evolving one or more times. ACO genes appear to have diversified mostly since the dicot-monocot split, as most genes cluster into a small number of monocot and dicot clades when the tree is rooted by genes from mosses. Gymnosperm ACOs were recovered as closely related and derived. PMID

  3. Low power Electro-optical filter: Constructed using silicon nanobeam resonator and PIN junction

    NASA Astrophysics Data System (ADS)

    Ebrahimy, Mehdi N.; Orafaei, Hamed; Andalib, Alireza; Alipuor-Banaei, Hamed

    2015-06-01

    In this paper, a high tunable Electro-optical filter is designed and simulated with low electric power consumption. A silicon nanobeam resonator based on one-dimensional photonic crystal in the form of Fabry-Perot structure, silicon-on-insulator waveguide, is proposed with a PIN junction. In designing nanobeam resonator, "deterministic design method" is used to achieve the high quality factor and high-transmission rate. Tuning of the resonant wavelength in the output channel of the filter is achieved by manipulating the refractive index of the active area by using the free-carrier dispersion effect. The output wavelengths of designed device can be tuned for the telecom-friendly 1.55 μm range. The device shows a wavelength shift higher than 3 nm for a power consumption of only 0.9 mW. Finally, the simulation results show that the provided device can be considered as a narrowband and tunable Electro-optical filter that is suitable for DWDM communication system.

  4. A security evaluation of the Rigid-fix crosses pin system used for anterior cruciate ligament reconstruction in tibial fixation site

    PubMed Central

    Fan, Huaqiang; Wang, Jian; Fu, Yangpan; Dong, Huixiang; Wang, Jianxiong; Tang, Cong; Huang, Changming; Shi, Zhanjun

    2014-01-01

    Our study aims to evaluate the safeness and feasibility that Rigid-fix cross pin system was used for hamstring graft anterior cruciate ligament (ACL) reconstruction in the tibial fixation site. In this study, eleven adult conservative cadaver knees were performed using the Rigid-fix Cross Pin device in the tibial fixation site for modeling the ACL reconstruction. The guide rod top was put through the tibial tunnel at the three horizontal positions: equal pace to articular facet (group A), the plane 5 mm below articular facet (group B), and the plane 10 mm below articular facet (group C). We gave four rotation positions to the cross-pin guide: 0°, 30°, 45°, 60° slope, referring to the parallel line of the posterior border of tibial plateau. We recorded the iatrogenic damages incidence, in the four different slope angle in the three groups, and then compare the incidence using Chi-Square test. Our results suggested that the incidence of chondral injury of tibial plateau in group B and group C was significantly lower compared to group A (χ 2 A-B = 27.077, χ 2 A-C 45.517, P = 0.000); However, there was no significant difference for the incidence penetrating the medial condyle of tibial plateau among the three groups (χ 2 = 5.733, P = 0.057); The highest incidence of injuring ligamentum transversum is in group A with 72.7%, especially at the 60° slope angle. In summary, our study suggested that in order to achieve the satisfactory clinical effect for the Rigid-fix system used in the tibia end fixation of ACL reconstruction surgery, the guide rod top should be put at the 5 mm below articular facet with a slope that parallel to the tibial medial plane at 30°-60° slope angle. PMID:25550991

  5. A Wirelessly Powered Micro-Spectrometer for Neural Probe-Pin Device

    NASA Technical Reports Server (NTRS)

    Choi, Sang H.; Kim, Min Hyuck; Song, Kyo D.; Yoon, Hargsoon; Lee, Uhn

    2015-01-01

    Treatment of neurological anomalies, places stringent demands on device functionality and size. A micro-spectrometer has been developed for use as an implantable neural probe to monitor neuro-chemistry in synapses. The microspectrometer, based on a NASA-invented miniature Fresnel grating, is capable of differentiating the emission spectra from various brain tissues. The micro-spectrometer meets the size requirements, and is able to probe the neuro-chemistry and suppression voltage typically associated with a neural anomaly. This neural probe-pin device (PPD) is equipped with wireless power technology (WPT) enabling operation in a continuous manner without requiring an implanted battery. The implanted neural PPD, together with a neural electronics interface and WPT, allow real-time measurement and control/feedback for remediation of neural anomalies. The design and performance of the combined PPD/WPT device for monitoring dopamine in a rat brain will be presented to demonstrate the current level of development. Future work on this device will involve the addition of an embedded expert system capable of performing semi-autonomous management of neural functions through a routine of sensing, processing, and control.

  6. Requalification of SPERT (Special Power Excursion Reactor Test) pins for use in university reactors

    SciTech Connect

    Snelgrove, J.L.; Domagala, R.F.; Dates, L.R.

    1986-12-01

    A series of nondestructive and destructive examinations have been performed on a representative sample of stainless steel-clad UO/sub 2/ fuel pins procured in the early-to-mid 1960s for the SPERT program. These examinations were undertaken in order to requalify the SPERT pins for use in converting university research reactors from the use of highly enriched uranium to the use of low-enriched uranium. The requalification program included visual and dimensional inspections of fuel pins and fuel pellets, radiographic inspections of welds, fill gas analyses, and chemical and spectrographic analyses of fuel and cladding materials. In general all attributes tested were within or very close to specified values, although some weld defects not covered by the original specifications were found. 1 ref., 4 figs., 11 tabs.

  7. Comparison of power spectra for tomosynthesis projections and reconstructed images

    PubMed Central

    Engstrom, Emma; Reiser, Ingrid; Nishikawa, Robert

    2009-01-01

    Burgess et al. [Med. Phys. 28, 419–437 (2001)] showed that the power spectrum of mammographic breast background follows a power law and that lesion detectability is affected by the power-law exponent β which measures the amount of structure in the background. Following the study of Burgess et al., the authors measured and compared the power-law exponent of mammographic backgrounds in tomosynthesis projections and reconstructed slices to investigate the effect of tomosynthesis imaging on background structure. Our data set consisted of 55 patient cases. For each case, regions of interest (ROIs) were extracted from both projection images and reconstructed slices. The periodogram of each ROI was computed by taking the squared modulus of the Fourier transform of the ROI. The power-law exponent was determined for each periodogram and averaged across all ROIs extracted from all projections or reconstructed slices for each patient data set. For the projections, the mean β averaged across the 55 cases was 3.06 (standard deviation of 0.21), while it was 2.87 (0.24) for the corresponding reconstructions. The difference in β for a given patient between the projection ROIs and the reconstructed ROIs averaged across the 55 cases was 0.194, which was statistically significant (p<0.001). The 95% CI for the difference between the mean value of β for the projections and reconstructions was [0.170, 0.218]. The results are consistent with the observation that the amount of breast structure in the tomosynthesis slice is reduced compared to projection mammography and that this may lead to improved lesion detectability. PMID:19544793

  8. Comparison of power spectra for tomosynthesis projections and reconstructed images

    SciTech Connect

    Engstrom, Emma; Reiser, Ingrid; Nishikawa, Robert

    2009-05-15

    Burgess et al. [Med. Phys. 28, 419-437 (2001)] showed that the power spectrum of mammographic breast background follows a power law and that lesion detectability is affected by the power-law exponent {beta} which measures the amount of structure in the background. Following the study of Burgess et al., the authors measured and compared the power-law exponent of mammographic backgrounds in tomosynthesis projections and reconstructed slices to investigate the effect of tomosynthesis imaging on background structure. Our data set consisted of 55 patient cases. For each case, regions of interest (ROIs) were extracted from both projection images and reconstructed slices. The periodogram of each ROI was computed by taking the squared modulus of the Fourier transform of the ROI. The power-law exponent was determined for each periodogram and averaged across all ROIs extracted from all projections or reconstructed slices for each patient data set. For the projections, the mean {beta} averaged across the 55 cases was 3.06 (standard deviation of 0.21), while it was 2.87 (0.24) for the corresponding reconstructions. The difference in {beta} for a given patient between the projection ROIs and the reconstructed ROIs averaged across the 55 cases was 0.194, which was statistically significant (p<0.001). The 95% CI for the difference between the mean value of {beta} for the projections and reconstructions was [0.170, 0.218]. The results are consistent with the observation that the amount of breast structure in the tomosynthesis slice is reduced compared to projection mammography and that this may lead to improved lesion detectability.

  9. Reconstruction of the primordial power spectrum from CMB data

    SciTech Connect

    Guo, Zong-Kuan; Zhang, Yuan-Zhong; Schwarz, Dominik J. E-mail: dschwarz@physik.uni-bielefeld.de

    2011-08-01

    Measuring the deviation from scale invariance of the primordial power spectrum is a critical test of inflation. In this paper we reconstruct the shape of the primordial power spectrum of curvature perturbations from the cosmic microwave background data, including the 7-year Wilkinson Microwave Anisotropy Probe data and the Atacama Cosmology Telescope 148 GHz data, by using a binning method of a cubic spline interpolation in log-log space. We find that the power-law spectrum is preferred by the data and that the Harrison-Zel'dovich spectrum is disfavored at 95% confidence level. These conclusions hold with and without allowing for tensor modes, however the simpler model without tensors is preferred by the data. We do not find evidence for a feature in the primordial power spectrum — in full agreement with generic predictions from cosmological inflation.

  10. Pin care

    MedlinePlus

    There are different types of pin-cleaning solutions. The two most common solutions are: Sterile water A mixture of half normal saline and half hydrogen peroxide Use the solution that your surgeon recommends. Supplies you will need to ...

  11. Fuel pin

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  12. Automatic 3D power line reconstruction of multi-angular imaging power line inspection system

    NASA Astrophysics Data System (ADS)

    Zhang, Wuming; Yan, Guangjian; Wang, Ning; Li, Qiaozhi; Zhao, Wei

    2007-06-01

    We develop a multi-angular imaging power line inspection system. Its main objective is to monitor the relative distance between high voltage power line and around objects, and alert if the warning threshold is exceeded. Our multi-angular imaging power line inspection system generates DSM of the power line passage, which comprises ground surface and ground objects, for example trees and houses, etc. For the purpose of revealing the dangerous regions, where ground objects are too close to the power line, 3D power line information should be extracted at the same time. In order to improve the automation level of extraction, reduce labour costs and human errors, an automatic 3D power line reconstruction method is proposed and implemented. It can be achieved by using epipolar constraint and prior knowledge of pole tower's height. After that, the proper 3D power line information can be obtained by space intersection using found homologous projections. The flight experiment result shows that the proposed method can successfully reconstruct 3D power line, and the measurement accuracy of the relative distance satisfies the user requirement of 0.5m.

  13. Dowel pin

    DOEpatents

    Wojcik, Thaddeus A.

    1978-01-01

    Two abutting members are locked together by reaming a hole entirely through one member and at least partly through the other, machining a circular groove in each through hole just below the surface of the member, press fitting a dowel pin having a thin wall extension on at least one end thereof into the hole in both members, a thin wall extension extending into each through hole, crimping or snapping the thin wall extension into the grooves to positively lock the dowel pin in place and, if necessary, tack welding the end of the thin-wall extension in place.

  14. Locking Pull Pin

    NASA Technical Reports Server (NTRS)

    Killgrove, T. O.

    1986-01-01

    Proposed self-locking pull pin not accidentally released by shock or vibration but intentionally released by pull on lanyard. Any rotational movement of main pin traps secondary pin: prevents further rotation and disengagement of main pin.

  15. Measurements of fuel pin/water hole worths and power peaking, void coefficients, and temperature coefficients for 4. 81 wt% enriched UO[sub 2] fuel rods

    SciTech Connect

    Harris, D.R.; Rohr, R.R.; Angelo, P.L.; Patrou, N.T.; Buckwheat, K.W.; Hayes, D.K.

    1990-01-01

    The Rensselaer Polytechnic Institute reactor critical facility is currently the only facility in North America providing critical measurement data in support of the light water reactor electric power industry. The reactor is fueled by 4.81 wt% [sup 235]U enriched UO[sub 2] high-density pellets in stainless steel clad fuel rods at the present time, although experiments with other fuels are being analyzed. The fuel pins are supported by inexpensive stainless steel lattice plates in a large open water tank. Three sets of lattice plates have been fabricated for fuel pins in square array with pitches 0.585, 0.613, and 0.640 in. (1.486, 0.613, and 1.656 cm, respectively) to provide a relevant range of water-to-fuel volume ratios. The measurements reported here are for the first of these, a relatively tight lattice of considerable interest for reactor physics methods for advanced fuels and reactors.

  16. Nondestrucive analysis of fuel pins

    DOEpatents

    Stepan, I.E.; Allard, N.P.; Suter, C.R.

    1972-11-03

    Disclosure is made of a method and a correspondingly adapted facility for the nondestructive analysis of the concentation of fuel and poison in a nuclear reactor fuel pin. The concentrations of fuel and poison in successive sections along the entire length of the fuel pin are determined by measuring the reactivity of a thermal reactor as each successive small section of the fuel pin is exposed to the neutron flux of the reactor core and comparing the measured reactivity with the reactivities measured for standard fuel pins having various known concentrations. Only a small section of the length of the fuel pin is exposed to the neutron flux at any one time while the remainder of the fuel pin is shielded from the neutron flux. In order to expose only a small section at any one time, a boron-10-lined dry traverse tube is passed through the test region within the core of a low-power thermal nuclear reactor which has a very high fuel sensitivity. A narrow window in the boron-10 lining is positioned at the core center line. The fuel pins are then systematically traversed through the tube past the narrow window such that successive small sections along the length of the fuel pin are exposed to the neutron flux which passes through the narrow window.

  17. Comparison of short-term results of bone tunnel enlargement between EndoButton CL and cross-pin fixation systems after chronic anterior cruciate ligament reconstruction with autologous quadrupled hamstring tendons.

    PubMed

    Kuskucu, S M

    2008-01-01

    We performed arthroscopic anterior cruciate ligament (ACL) reconstructions of chronic ACL rupture with autologous hamstring tendon grafts in males (mean age 23.9 years). Thirty-two cross-pin fixations and 24 EndoButton CL fixations were performed on the femoral side. Distal fixations on the tibial side were maintained with interference screws plus a staple. Tunnel enlargement was evaluated using X-rays. Femoral and tibial tunnels were measured at three levels 5 mm apart, and average enlargement was calculated after correction for magnification. Tunnel enlargement 12 months after surgery was greater for the EndoButton CL system (femoral side 43.71%, tibial side 51.11%) than for the cross-pin system (femoral side 32.61%, tibial side 25.62%); the difference was significant only on the tibial side. Both proximal fixation techniques were judged clinically successful (follow-up 16 - 36 months). The far fixation point in the EndoButton CL group may be related to mechanical loosening. PMID:18230264

  18. Linear Equivalent Circuit and Current Sources Model Including Separation Resistances in the Ground Connection for Multiple Power-Supply Pin LSI

    NASA Astrophysics Data System (ADS)

    Saito, Yoshiyuki; Yasuhara, Masakatsu; Mabuchi, Yuichi; Matsushima, Tohlu; Hisakado, Takashi; Wada, Osami

    An EMC macro-model for LSIs, named the LECCS-core model, is under development for simulating high frequency noise in power supply currents. In this paper, the conventional LECCS-core model is extended by adding resistances in the ground connection of an LSI, in order to separate the core block and the analog block. The model parameters are identified using symbolic analysis and least-square optimization. Using this new model, the transfer impedances between different power supply pins can be simulated accurately. Additionally we derived the equivalent internal current sources by using that model. As a result, we confirmed that the internal current sources were improved. In conclusion, we confirmed that the configuration of the linear equivalent circuit and our modeling method can be applied widely to microcontrollers of the same block configuration.

  19. Wavefront aberration reconstruction from tangential refractive powers measured with spatial dynamic skiascopy.

    PubMed

    Barbero, Sergio

    2012-12-20

    The aim of this work was to study, using numerical simulations, the attainable level of accuracy to reconstruct the wavefront aberrations from tangential refractive power data measured with dynamic skiascopy. Two mathematical methods have been implemented. The first one is based on curve integration of the curvature data, previously interpolated with cubic splines. The second one reconstructs the three-dimensional wavefront surface, represented by a Zernike polynomial expansion, using a two-step least-squares method. The different factors affecting the reconstruction--noise, sampling, and wavefront patterns--were quantified. The results provide useful information to design more efficient experimental setups based on spatial dynamic skiascopy. PMID:23262600

  20. Dependence on the incident light power of the internal electric fields in a GaAs p-i-n solar cell according to bright photoreflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Jo, Hyun-Jun; Mun, Young Hee; Kim, Jong Su; Lee, Sang Jun

    2016-07-01

    Bright photoreflectance (BPR) spectroscopy at room temperature is used to examine the internal electric fields in a GaAs p-i-n solar cell for their dependence on the incident light power. Electric fields are observed at 30 µW and 100 µW of incident light. With increasing power, the strengths of the two electric fields are reduced due to the photovoltage effect. The electric field observed at 30 µW is assigned to the p-i interface, which is close to the surface. The other electric field is due to the i-n interface because the incident light penetrates deeper as the light power is increased. The electric field strength of 35.6 kV/cm at the p-i interface is lower than that of 42.9 kV/cm at the i-n interface at 500 µW of light power because the photovoltage effect is proportional to the number of photo-generated carriers, which is reduced as the distance from the surface increases. When the incident light power is similar to the excitation beam power, the electric fields at the p-i interface are saturated.

  1. Reconstruction of the primordial power spectrum using temperature and polarisation data from multiple experiments

    SciTech Connect

    Nicholson, Gavin; Contaldi, Carlo R. E-mail: c.contaldi@imperial.ac.uk

    2009-07-01

    We develop a method to reconstruct the primordial power spectrum, P(k), using both temperature and polarisation data from the joint analysis of a number of Cosmic Microwave Background (CMB) observations. The method is an extension of the Richardson-Lucy algorithm, first applied in this context by Shafieloo and Souradeep [1]. We show how the inclusion of polarisation measurements can decrease the uncertainty in the reconstructed power spectrum. In particular, the polarisation data can constrain oscillations in the spectrum more effectively than total intensity only measurements. We apply the estimator to a compilation of current CMB results. The reconstructed spectrum is consistent with the best-fit power spectrum although we find evidence for a 'dip' in the power on scales k ≈ 0.002 Mpc{sup −1}. This feature appears to be associated with the WMAP power in the region 18 ≤ l ≤ 26 which is consistently below best-fit models. We also forecast the reconstruction for a simulated, Planck-like [2] survey including sample variance limited polarisation data.

  2. Reconstruction of the primordial power spectrum using temperature and polarisation data from multiple experiments

    NASA Astrophysics Data System (ADS)

    Nicholson, Gavin; Contaldi, Carlo R.

    2009-07-01

    We develop a method to reconstruct the primordial power spectrum, P(k), using both temperature and polarisation data from the joint analysis of a number of Cosmic Microwave Background (CMB) observations. The method is an extension of the Richardson-Lucy algorithm, first applied in this context by Shafieloo & Souradeep [1]. We show how the inclusion of polarisation measurements can decrease the uncertainty in the reconstructed power spectrum. In particular, the polarisation data can constrain oscillations in the spectrum more effectively than total intensity only measurements. We apply the estimator to a compilation of current CMB results. The reconstructed spectrum is consistent with the best-fit power spectrum although we find evidence for a `dip' in the power on scales k approx 0.002 Mpc-1. This feature appears to be associated with the WMAP power in the region 18 <= ell <= 26 which is consistently below best-fit models. We also forecast the reconstruction for a simulated, Planck-like [2] survey including sample variance limited polarisation data.

  3. Pins for direct restorations.

    PubMed

    Papa, J; Wilson, P R; Tyas, M J

    1993-10-01

    Self-threading dentine pins permit the retention of large complex direct restorations but there are problems associated with their placement. Strain and crazing of dentine following pin insertion and pulpal and lateral perforations are common. Perforations can be avoided by operator awareness of tooth morphology. Strain and crazing has been found to be minimized by unscrewing the pin slightly after insertion, by using pins with a tap thread, and by using the smallest pin possible. Twist drill form and dulling affects the pin channel shape which in turn influences pin seating. A lack of standardization of pin and twist drill diameter and length has been implicated as the cause of poor pin retention. Manufacturers, in an attempt to standardize the depth of penetration of pins, have incorporated shoulders at the midpoint of the pin, which has met with varying success. More research in the area of limiting pin penetration is necessary, as well as attempts to improve the quality control of pin and twist drill manufacture. PMID:8227686

  4. On minimally parametric primordial power spectrum reconstruction and the evidence for a red tilt

    SciTech Connect

    Verde, Licia; Peiris, Hiranya E-mail: lverde@astro.princeton.edu

    2008-07-15

    The latest cosmological data seem to indicate a significant deviation from scale invariance of the primordial power spectrum when parameterized either by a power law or by a spectral index with non-zero 'running'. This deviation, by itself, serves as a powerful tool for discriminating among theories for the origin of cosmological structures such as inflationary models. Here, we use a minimally parametric smoothing spline technique to reconstruct the shape of the primordial power spectrum. This technique is well suited to searching for smooth features in the primordial power spectrum such as deviations from scale invariance or a running spectral index, although it would recover sharp features of high statistical significance. We use the WMAP three-year results in combination with data from a suite of higher resolution cosmic microwave background experiments (including the latest ACBAR 2008 release), as well as large-scale structure data from SDSS and 2dFGRS. We employ cross-validation to assess, using the data themselves, the optimal amount of smoothness in the primordial power spectrum consistent with the data. This minimally parametric reconstruction supports the evidence for a power law primordial power spectrum with a red tilt, but not for deviations from a power law power spectrum. Smooth variations in the primordial power spectrum are not significantly degenerate with the other cosmological parameters.

  5. Reusable Mechanical Pin Puller

    NASA Technical Reports Server (NTRS)

    Ngo, Son; Farley, Rodger; Devine, ED

    1991-01-01

    Reusable mechanical pin puller relatively simple spring-loaded trigger mechanism. Designed to save money and increase safety as substitute for costly and potentially dangerous pyrotechnic pin pullers used in development and testing of deployment mechanisms.

  6. Power Relationships in Rumpelstiltskin: A Textual Comparison of a Traditional and a Reconstructed Fairy Tale

    ERIC Educational Resources Information Center

    Kelley, Jane E.

    2008-01-01

    Reconstructed fairy tales provide a different point of view and challenge the assumptions of a common set of values; for that reason, these stories provide a medium in which to examine power relationships in texts by applying a critical multicultural analysis (Botelho & Rudman, forthcoming, 2008, "A critical multicultural analysis of children's…

  7. PinBus Interface Design

    SciTech Connect

    Hammerstrom, Donald J.; Adgerson, Jewel D.; Sastry, Chellury; Pratt, Richard M.; Pratt, Robert G.

    2009-12-30

    On behalf of the U.S. Department of Energy, PNNL has explored and expanded upon a simple control interface that might have merit for the inexpensive communication of smart grid operational objectives (demand response, for example) to small electric end-use devices and appliances. The approach relies on bi-directional communication via the electrical voltage states of from one to eight shared interconnection pins. The name PinBus has been suggested and adopted for the proposed interface protocol. The protocol is defined through the presentation of state diagrams and the pins’ functional definitions. Both simulations and laboratory demonstrations are being conducted to demonstrate the elegance and power of the suggested approach. PinBus supports a very high degree of interoperability across its interfaces, allowing innumerable pairings of devices and communication protocols and supporting the practice of practically any smart grid use case.

  8. Red, Straight, no bends: primordial power spectrum reconstruction from CMB and large-scale structure

    NASA Astrophysics Data System (ADS)

    Ravenni, Andrea; Verde, Licia; Cuesta, Antonio J.

    2016-08-01

    We present a minimally parametric, model independent reconstruction of the shape of the primordial power spectrum. Our smoothing spline technique is well-suited to search for smooth features such as deviations from scale invariance, and deviations from a power law such as running of the spectral index or small-scale power suppression. We use a comprehensive set of the state-of the art cosmological data: Planck observations of the temperature and polarisation anisotropies of the cosmic microwave background, WiggleZ and Sloan Digital Sky Survey Data Release 7 galaxy power spectra and the Canada-France-Hawaii Lensing Survey correlation function. This reconstruction strongly supports the evidence for a power law primordial power spectrum with a red tilt and disfavours deviations from a power law power spectrum including small-scale power suppression such as that induced by significantly massive neutrinos. This offers a powerful confirmation of the inflationary paradigm, justifying the adoption of the inflationary prior in cosmological analyses.

  9. Piezoelectric Pins for Use as Dust Detectors

    NASA Astrophysics Data System (ADS)

    Manning, H. L. K.; Campbell, I. H.; Nelson, K. A.; Yager, J. R.

    2002-09-01

    Piezoelectric pins are devices currently used in a number of applications including detecting elementary particle beams, monitoring volcanoes, and detecting high-speed micro-sized particles. These pins provide a means of studying ejecta from cratering processes in the laboratory and offer a potential lightweight, low power, flight dust detector. Using the hypervelocity dust particle accelerator at Concordia College in Moorhead, Minnesota, we have investigated the transient charge generated by piezoelectric pins impacted by dust particles. Carbonyl iron dust particles of 0.5-5 micrometer diameter having speeds ranging from 1-5 km/sec impacted the pins. The DC-100 MHz pin response was recorded and analyzed. The transient pin response to a single particle consists of many charge pulses of alternating sign (less than 10 ns in duration) separated by the pressure wave propagation time across the crystal (typically 100 ns). The charge produced by the pin changes sign when the pressure waves in the piezoelectric crystal reflect off of the metal electrodes. The magnitude of the pin response as a function of the impacting particle properties is presented and discussed. Pins using both polycrystalline PZT and single crystal LiNbO3 as the piezoelectric material were studied. This work is supported at Concordia College by the Minnesota Space Grant Consortium.

  10. The effect of frequency on atmospheric pressure glow discharge in a pin-to-plate gap sustained by a resonant power supply

    NASA Astrophysics Data System (ADS)

    Wang, Yong Sheng; Ding, Wei Dong; Wang, Ya Nan; Wang, Jia Chen; Li, Fang; Fan, Chuan

    2016-06-01

    More and more researchers have been attracted to the research of atmospheric pressure glow discharge (APGD) because of its great prospect in numerous industrial applications. Nevertheless, almost all of the industrial applications are based on achievement of stable, large-volume, and uniform APGD. In a previous study, stable filamentary APGD was obtained by applying a resonant power supply between pin-to-plate electrodes which could limit the peak value of discharge current to supress the glow-to-arc transition through a series-wound resonance principle. The filamentary APGD is centimeter-level in the length but only several millimeters in diameter. Therefore, in order to obtain large-volume and uniform APGD, it is significant to study how to diffuse filamentary APGD in radial direction. With the increasing resonant frequency of alternating current discharge, excited particles (mainly including energetic electrons and trapped ions left from the previous half-cycle discharge) in the electrodes gap increase, which benefits obtaining stable self-sustaining APGD. In this paper, mechanism and law of the influence of resonant frequency on the diffusion of filamentary APGD in ambient air were studied. By comparing the photos of discharge plasma and waveforms of the discharge voltage and current, it is found that the volume of the glow discharge plasma enlarges as the resonant frequency of the power supply increases. It is very significant and anticipating to study how to obtain stable, large-volume, and uniform APGD in ambient air by the resonant power supply.

  11. 18. SHEAR PIN, UNIT 24 GORGE POWERHOUSE. THE WICKET GATES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. SHEAR PIN, UNIT 24 GORGE POWERHOUSE. THE WICKET GATES ON THE TURBINE ARE EACH EQUIPPED WITH A SHEAR PIN AND OIL PRESSURE GAUGE. IF A GATE JAMS, THE PIN SMEARS AND THE CHANGE IN OIL PRESSURE TRIGGERS AN ALARM, 1989. - Skagit Power Development, Gorge Powerhouse, On Skagit River, 0.4 mile upstream from Newhalem, Newhalem, Whatcom County, WA

  12. Reconstruction of crystal band structure from the power spectrum of strong-field generated high harmonics

    NASA Astrophysics Data System (ADS)

    Wang, Chang-Ming; Ho, Tak-San; Chu, Shih-I.

    2016-05-01

    The study of high harmonic generation in solid driven by intense laser fields is a subject of much current interest. Recently we introduce a new optimization method to directly reconstruct the band structure of the crystal from the power spectrum of strong-field generated high harmonics. Without loss of generality, the reconstruction is formulated for a one-dimensional single band model as a minimization problem and solved by a derivative-free unconstrained optimization algorithm-NEWUOA. The method can be readily generalized to treat multi-band problems. Numerical simulations are presented to demonstrate the applicability of the method, and the reconstructed band structure is found to be in excellent agreement with the exact one. It is also shown that our optimization method remains robust and efficient even starting from the poorly guessed band structure.

  13. Nuclear fuel pin scanner

    DOEpatents

    Bramblett, Richard L.; Preskitt, Charles A.

    1987-03-03

    Systems and methods for inspection of nuclear fuel pins to determine fiss loading and uniformity. The system includes infeed mechanisms which stockpile, identify and install nuclear fuel pins into an irradiator. The irradiator provides extended activation times using an approximately cylindrical arrangement of numerous fuel pins. The fuel pins can be arranged in a magazine which is rotated about a longitudinal axis of rotation. A source of activating radiation is positioned equidistant from the fuel pins along the longitudinal axis of rotation. The source of activating radiation is preferably oscillated along the axis to uniformly activate the fuel pins. A detector is provided downstream of the irradiator. The detector uses a plurality of detector elements arranged in an axial array. Each detector element inspects a segment of the fuel pin. The activated fuel pin being inspected in the detector is oscillated repeatedly over a distance equal to the spacing between adjacent detector elements, thereby multiplying the effective time available for detecting radiation emissions from the activated fuel pin.

  14. Experimental verification of reconstructed absorbers embedded in scattering media by optical power ratio distribution.

    PubMed

    Yamaoki, Toshihiko; Hamada, Hiroaki; Matoba, Osamu

    2016-09-01

    Experimental investigation to show the effectiveness of the extraction method of absorber information in a scattering medium by taking the output power ratio distribution is presented. In the experiment, two metallic wires sandwiched by three homogeneous scattering media are used as absorbers in transmission geometry. The output power ratio distributions can extract the influence of the absorbers to enhance the optical signal. The peak position of the output power ratio distributions agree with the results suggested by numerical simulation. From the reconstructed results of tomography in the scattering media, we have confirmed that the tomographic image of two wires can distinguish them successfully from 41×21 output power ratio distributions by using continuous-wave light. PMID:27607261

  15. Straight SU-8 pins

    NASA Astrophysics Data System (ADS)

    Safavieh, R.; Pla Roca, M.; Qasaimeh, M. A.; Mirzaei, M.; Juncker, D.

    2010-05-01

    SU-8 can be patterned with high resolution, is flexible and tough. These characteristics qualify SU-8 as a material for making spotting pins for printing DNA and protein microarrays, and it can potentially replace the commonly used silicon and steel pins that are expensive, brittle in the case of silicon and can damage the substrate during the printing process. SU-8, however, accumulates large internal stress during fabrication and, as a consequence, thin and long SU-8 structures bend and coil up, which precludes using it for long, freestanding structures such as pins. Here we introduce (i) a novel fabrication process that allows the making of 30 mm long, straight spotting pins that feature (ii) a new design and surface chemistry treatments for better capillary flow control and more homogeneous spotting. A key innovation for the fabrication is a post-processing annealing step with slow temperature ramping and mechanical clamping between two identical substrates to minimize stress buildup and render it symmetric, respectively, which together yield a straight SU-8 structure. SU-8 pins fabricated using this process are compliant and resilient and can buckle without damage during printing. The pins comprise a novel flow stop valve for accurate metering of fluids, and their surface was chemically patterned to render the outside of the pin hydrophobic while the inside of the slit is hydrophilic, and the slit thus spontaneously fills when dipped into a solution while preventing droplet attachment on the outside. A single SU-8 pin was used to print 1392 protein spots in one run. SU-8 pins are inexpensive, straightforward to fabricate, robust and may be used as disposable pins for microarray fabrication. These pins serve as an illustration of the potential application of ultralow stress SU-8 for making freestanding microfabricated polymer microstructures.

  16. PINS Spectrum Identification Guide

    SciTech Connect

    A.J. Caffrey

    2012-03-01

    The Portable Isotopic Neutron Spectroscopy—PINS, for short—system identifies the chemicals inside munitions and containers without opening them, a decided safety advantage if the fill chemical is a hazardous substance like a chemical warfare agent or an explosive. The PINS Spectrum Identification Guide is intended as a reference for technical professionals responsible for the interpretation of PINS gamma-ray spectra. The guide is divided into two parts. The three chapters that constitute Part I cover the science and technology of PINS. Neutron activation analysis is the focus of Chapter 1. Chapter 2 explores PINS hardware, software, and related operational issues. Gamma-ray spectral analysis basics are introduced in Chapter 3. The six chapters of Part II cover the identification of PINS spectra in detail. Like the PINS decision tree logic, these chapters are organized by chemical element: phosphorus-based chemicals, chlorine-based chemicals, etc. These descriptions of hazardous, toxic, and/or explosive chemicals conclude with a chapter on the identification of the inert chemicals, e.g. sand, used to fill practice munitions.

  17. Reconstruction of a nonminimal coupling theory with scale-invariant power spectrum

    SciTech Connect

    Qiu, Taotao

    2012-06-01

    A nonminimal coupling single scalar field theory, when transformed from Jordan frame to Einstein frame, can act like a minimal coupling one. Making use of this property, we investigate how a nonminimal coupling theory with scale-invariant power spectrum could be reconstructed from its minimal coupling counterpart, which can be applied in the early universe. Thanks to the coupling to gravity, the equation of state of our universe for a scale-invariant power spectrum can be relaxed, and the relation between the parameters in the action can be obtained. This approach also provides a means to address the Big-Bang puzzles and anisotropy problem in the nonminimal coupling model within Jordan frame. Due to the equivalence between the two frames, one may be able to find models that are free of the horizon, flatness, singularity as well as anisotropy problems.

  18. Scalar field reconstruction of power-law entropy-corrected holographic dark energy

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Esmaeil; Sheykhi, Ahmad

    2011-10-01

    A so-called 'power-law entropy-corrected holographic dark energy' (PLECHDE) was recently proposed to explain the dark energy (DE)-dominated universe. This model is based on the power-law corrections to black hole entropy that appear when dealing with the entanglement of quantum fields between the inside and the outside of the horizon. In this paper, we suggest a correspondence between the interacting PLECHDE and the tachyon, quintessence, K-essence and dilaton scalar field models of DE in a non-flat Friedmann-Robertson-Walker universe. Then, we reconstruct the potential terms accordingly, and present the dynamical equations that describe the evolution of the scalar field DE models.

  19. Powered Flight Design and Reconstructed Performance Summary for the Mars Science Laboratory Mission

    NASA Technical Reports Server (NTRS)

    Sell, Steven; Chen, Allen; Davis, Jody; San Martin, Miguel; Serricchio, Frederick; Singh, Gurkirpal

    2013-01-01

    The Powered Flight segment of Mars Science Laboratory's (MSL) Entry, Descent, and Landing (EDL) system extends from backshell separation through landing. This segment is responsible for removing the final 0.1% of the kinetic energy dissipated during EDL and culminating with the successful touchdown of the rover on the surface of Mars. Many challenges exist in the Powered Flight segment: extraction of Powered Descent Vehicle from the backshell, performing a 300m divert maneuver to avoid the backshell and parachute, slowing the descent from 85 m/s to 0.75 m/s and successfully lowering the rover on a 7.5m bridle beneath the rocket-powered Descent Stage and gently placing it on the surface using the Sky Crane Maneuver. Finally, the nearly-spent Descent Stage must execute a Flyaway maneuver to ensure surface impact a safe distance from the Rover. This paper provides an overview of the powered flight design, key features, and event timeline. It also summarizes Curiosity's as flown performance on the night of August 5th as reconstructed by the flight team.

  20. Spring loaded locator pin assembly

    DOEpatents

    Groll, T.A.; White, J.P.

    1998-03-03

    This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece. 5 figs.

  1. Spring loaded locator pin assembly

    DOEpatents

    Groll, Todd A.; White, James P.

    1998-01-01

    This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece.

  2. A double tuned rail damper—increased damping at the two first pinned-pinned frequencies

    NASA Astrophysics Data System (ADS)

    Maes, J.; Sol, H.

    2003-10-01

    Railway-induced vibrations are a growing matter of environmental concern. The rapid development of transportation, the increase of vehicle speeds and vehicle weights have resulted in higher vibration levels. In the meantime vibrations that were tolerated in the past are now considered to be a nuisance. Numerous solutions have been proposed to remedy these problems. The majority only acts on a specific part of the dynamic behaviour of the track. This paper presents a possible solution to reduce the noise generated by the 'pinned-pinned' frequencies. Pinned-pinned frequencies correspond with standing waves whose nodes are positioned exactly at the sleeper supports. The two first pinned-pinned frequencies are situated approximately at 950 and 2200 Hz (UIC60-rail and sleeper spacing of 0.60 m). To attenuate these vibrations, the Department of MEMC at the VUB has developed a dynamic vibration absorber called the Double Tuned Rail Damper (DTRD). The DTRD is mounted between two sleepers on the rail and is powered by the motion of the rail. The DTRD consists of two major parts: a steel plate which is connected to the rail with an interface of an elastic layer, and a rubber mass. The two first resonance frequencies of the steel plate coincide with the targeted pinned-pinned frequencies of the rail. The rubber mass acts as a motion controller and energy absorber. Measurements at a test track of the French railway company (SNCF) have shown considerable attenuation of the envisaged pinned-pinned frequencies. The attenuation rate surpasses 5 dB/m at certain frequency bands.

  3. Dynamic-Feature Extraction, Attribution and Reconstruction (DEAR) Method for Power System Model Reduction

    SciTech Connect

    Wang, Shaobu; Lu, Shuai; Zhou, Ning; Lin, Guang; Elizondo, Marcelo A.; Pai, M. A.

    2014-09-04

    In interconnected power systems, dynamic model reduction can be applied on generators outside the area of interest to mitigate the computational cost with transient stability studies. This paper presents an approach of deriving the reduced dynamic model of the external area based on dynamic response measurements, which comprises of three steps, dynamic-feature extraction, attribution and reconstruction (DEAR). In the DEAR approach, a feature extraction technique, such as singular value decomposition (SVD), is applied to the measured generator dynamics after a disturbance. Characteristic generators are then identified in the feature attribution step for matching the extracted dynamic features with the highest similarity, forming a suboptimal ‘basis’ of system dynamics. In the reconstruction step, generator state variables such as rotor angles and voltage magnitudes are approximated with a linear combination of the characteristic generators, resulting in a quasi-nonlinear reduced model of the original external system. Network model is un-changed in the DEAR method. Tests on several IEEE standard systems show that the proposed method gets better reduction ratio and response errors than the traditional coherency aggregation methods.

  4. PINS-3X Operations

    SciTech Connect

    E.H. Seabury

    2013-09-01

    Idaho National Laboratory’s (INL’s) Portable Isotopic Neutron Spectroscopy System (PINS) non-intrusively identifies the chemical fill of munitions and sealed containers. The PINS-3X variant of the system is used to identify explosives and uses a deuterium-tritium (DT) electronic neutron generator (ENG) as the neutron source. Use of the system, including possession and use of the neutron generator and shipment of the system components requires compliance with a number of regulations. This report outlines some of these requirements as well as some of the requirements in using the system outside of INL.

  5. Three-dimensional pin-to-pin analyses of VVER-440 cores by the MOBY-DICK code

    SciTech Connect

    Lehmann, M.; Mikolas, P.

    1994-12-31

    Nuclear design for the Dukovany (EDU) VVER-440s nuclear power plant is routinely performed by the MOBY-DICK system. After its implementation on Hewlett Packard series 700 workstations, it is able to perform routinely three-dimensional pin-to-pin core analyses. For purposes of code validation, the benchmark prepared from EDU operational data was solved.

  6. Diffusion inspires selection of pinning nodes in pinning control

    NASA Astrophysics Data System (ADS)

    Zhou, Ming-Yang; He, Xingsheng; Fu, Zhong-Qian; Liao, Hao; Cai, Shi-min; Zhuo, Zhao

    2016-03-01

    The outstanding problem of controlling a complex network via pinning is related to network dynamics and has the potential to master large-scale real-world systems as well. This paper addresses the heart issue about how to choose pinning nodes for pinning control, where pinning control aims to control a network to an identical state by injecting feedback control signals to a small fraction of nodes. We explore networks' controllability from not only mathematical analysis, but also the aspects of network topology and information diffusion. Then, the connection between pinning control and information diffusion is given, and pinning node selection is transferred into multi-spreader problem in information diffusion. Based on information diffusion, a heuristic method is proposed to select pinning nodes by optimizing the spreading ability of multiple spreaders. The proposed method greatly improves the controllability of large practical networks, and provides a new perspective to investigate pinning node selection.

  7. Reconstruction of the primordial power spectrum of curvature perturbations using multiple data sets

    NASA Astrophysics Data System (ADS)

    Hunt, Paul; Sarkar, Subir

    2014-01-01

    Detailed knowledge of the primordial power spectrum of curvature perturbations is essential both in order to elucidate the physical mechanism (`inflation') which generated it, and for estimating the cosmological parameters from observations of the cosmic microwave background and large-scale structure. Hence it ought to be extracted from such data in a model-independent manner, however this is difficult because relevant cosmological observables are given by a convolution of the primordial perturbations with some smoothing kernel which depends on both the assumed world model and the matter content of the universe. Moreover the deconvolution problem is ill-conditioned so a regularisation scheme must be employed to control error propagation. We demonstrate that `Tikhonov regularisation' can robustly reconstruct the primordial spectrum from multiple cosmological data sets, a significant advantage being that both its uncertainty and resolution are then quantified. Using Monte Carlo simulations we investigate several regularisation parameter selection methods and find that generalised cross-validation and Mallow's Cp method give optimal results. We apply our inversion procedure to data from the Wilkinson Microwave Anisotropy Probe, other ground-based small angular scale CMB experiments, and the Sloan Digital Sky Survey. The reconstructed spectrum (assuming the standard ΛCDM cosmology) is not scale-free but has an infrared cutoff at klesssim5 × 10-4 Mpc-1 (due to the anomalously low CMB quadrupole) and several features with ~ 2σ significance at k/Mpc-1 ~ 0.0013-0.0025, 0.0362-0.0402 and 0.051-0.056, reflecting the `WMAP glitches'. To test whether these are indeed real will require more accurate data, such as from the Planck satellite and new ground-based experiments.

  8. Reconstruction of the primordial power spectrum of curvature perturbations using multiple data sets

    SciTech Connect

    Hunt, Paul; Sarkar, Subir E-mail: s.sarkar@physics.ox.ac.uk

    2014-01-01

    Detailed knowledge of the primordial power spectrum of curvature perturbations is essential both in order to elucidate the physical mechanism ('inflation') which generated it, and for estimating the cosmological parameters from observations of the cosmic microwave background and large-scale structure. Hence it ought to be extracted from such data in a model-independent manner, however this is difficult because relevant cosmological observables are given by a convolution of the primordial perturbations with some smoothing kernel which depends on both the assumed world model and the matter content of the universe. Moreover the deconvolution problem is ill-conditioned so a regularisation scheme must be employed to control error propagation. We demonstrate that 'Tikhonov regularisation' can robustly reconstruct the primordial spectrum from multiple cosmological data sets, a significant advantage being that both its uncertainty and resolution are then quantified. Using Monte Carlo simulations we investigate several regularisation parameter selection methods and find that generalised cross-validation and Mallow's C{sub p} method give optimal results. We apply our inversion procedure to data from the Wilkinson Microwave Anisotropy Probe, other ground-based small angular scale CMB experiments, and the Sloan Digital Sky Survey. The reconstructed spectrum (assuming the standard ΛCDM cosmology) is not scale-free but has an infrared cutoff at k∼<5 × 10{sup −4} Mpc{sup −1} (due to the anomalously low CMB quadrupole) and several features with ∼ 2σ significance at k/Mpc{sup −1} ∼ 0.0013–0.0025, 0.0362–0.0402 and 0.051–0.056, reflecting the 'WMAP glitches'. To test whether these are indeed real will require more accurate data, such as from the Planck satellite and new ground-based experiments.

  9. Generic inference of inflation models by non-Gaussianity and primordial power spectrum reconstruction

    SciTech Connect

    Dorn, Sebastian; Enßlin, Torsten A.; Ramirez, Erandy; Kunze, Kerstin E.

    2014-06-01

    We present a generic inference method for inflation models from observational data by the usage of higher-order statistics of the curvature perturbation on uniform density hypersurfaces. This method is based on the calculation of the posterior for the primordial non-Gaussianity parameters f{sub NL} and g{sub NL}, which in general depend on specific parameters of inflation and reheating models, and enables to discriminate among the still viable inflation models. To keep analyticity as far as possible to dispense with numerically expensive sampling techniques a saddle-point approximation is introduced, whose precision is validated for a numerical toy example. The mathematical formulation is done in a generic way so that the approach remains applicable to cosmic microwave background data as well as to large scale structure data. Additionally, we review a few currently interesting inflation models and present numerical toy examples thereof in two and three dimensions to demonstrate the efficiency of the higher-order statistics method. A second quantity of interest is the primordial power spectrum. Here, we present two Bayesian methods to infer it from observational data, the so called critical filter and an extension thereof with smoothness prior, both allowing for a non-parametric spectrum reconstruction. These methods are able to reconstruct the spectra of the observed perturbations and the primordial ones of curvature perturbation even in case of non-Gaussianity and partial sky coverage. We argue that observables like T- and B-modes permit to measure both spectra. This also allows to infer the level of non-Gaussianity generated since inflation.

  10. De-pinning of disordered bosonic chains

    NASA Astrophysics Data System (ADS)

    Vogt, N.; Cole, J. H.; Shnirman, A.

    2016-05-01

    We consider onset of transport (de-pinning) in one-dimensional bosonic chains with a repulsive boson–boson interaction that decays exponentially on large length-scales. Our study is relevant for (i) de-pinning of Cooper-pairs in Josephson junction arrays; (ii) de-pinning of magnetic flux quanta in quantum-phase-slip ladders, i.e. arrays of superconducting wires in a ladder-configuration that allow for the coherent tunneling of flux quanta. In the low-frequency, long wave-length regime these chains can be mapped onto an effective model of a one-dimensional elastic field in a disordered potential. The standard de-pinning theories address infinitely long systems in two limiting cases: (a) of uncorrelated disorder (zero correlation length); (b) of long range power-law correlated disorder (infinite correlation length). In this paper we study numerically chains of finite length in the intermediate case of long but finite disorder correlation length. This regime is of relevance for, e.g., the experimental systems mentioned above. We study the interplay of three length scales: the system length, the interaction range, the correlation length of disorder. In particular, we observe the crossover between the solitonic onset of transport in arrays shorter than the disorder correlation length to onset of transport by de-pinning for longer arrays.

  11. Lever-Arm Pin Puller

    NASA Technical Reports Server (NTRS)

    Macmartin, Malcolm

    1994-01-01

    Mechanism holds retaining pins in place except when actuated to release pins quickly. Mechanism is integral part of cover designed to be removed with simple downward motion of hand. Before removal, mechanism secures cover in place. After removal, mechanism holds retaining pins for reuse.

  12. Pin puller impact shock attenuation

    NASA Technical Reports Server (NTRS)

    Auclair, G. F.; Leonard, B. S.; Robbins, R. E.; Proffitt, W. L.

    1976-01-01

    Design of a pin arresting mechanism for a pyrotechnically actuated pin puller is reviewed. The investigative approach is discussed and the impact shock test results for various candidate designs are presented. The selected pin arresting design reduced the peak value of the shock response spectrum by five to one.

  13. 13. UNDERSIDE OF THROUGHWAY SHOWING MAIN CHORDS, SUSPENSION EYEBAR PIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. UNDERSIDE OF THROUGHWAY SHOWING MAIN CHORDS, SUSPENSION EYE-BAR PIN CONNECTORS, LOWER CHORD EYEBARS AND LATERAL BRACING MEMBERS - Spruce Street Bridge, East Spruce Street, 500 Block, spanning Power Canal, Sault Ste. Marie, Chippewa County, MI

  14. 10. EYEBAR PIN CONNECTION JOINING VERTICAL SUSPENSION STRINGER WITH LATERAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. EYEBAR PIN CONNECTION JOINING VERTICAL SUSPENSION STRINGER WITH LATERAL BRACING MEMBERS - Spruce Street Bridge, East Spruce Street, 500 Block, spanning Power Canal, Sault Ste. Marie, Chippewa County, MI

  15. Spatial Pinning Control

    NASA Astrophysics Data System (ADS)

    Frasca, Mattia; Buscarino, Arturo; Rizzo, Alessandro; Fortuna, Luigi

    2012-05-01

    In this Letter, we introduce the concept of spatial pinning control for a network of mobile chaotic agents. In a planar space, N agents move as random walkers and interact according to a time-varying r-disk proximity graph. A control input is applied only to those agents which enter a given area, called control region. The control is effective in driving all the agents to a reference evolution and has better performance than pinning control on a fixed set of agents. We derive analytical conditions on the relative size of the control region and the agent density for the global convergence of the system to the reference evolution and study the system under different regimes inherited by the velocity.

  16. Improving Functional Performance and Muscle Power 4-to-6 Months After Anterior Cruciate Ligament Reconstruction.

    PubMed

    Souissi, Sabrine; Wong, Del P; Dellal, Alexandre; Croisier, Jean-Louis; Ellouze, Zied; Chamari, Karim

    2011-01-01

    The purpose of this study was to examine the effects of 8-week retraining programs, with either two or three training sessions per week, on measures of functional performance and muscular power in athletes with anterior cruciate ligament reconstruction (ACLR). Sixteen male athletes were randomly assigned to two groups after ACLR: a functional training group (FTG, n = 8) training 2 intense sessions per week (4hrs/week), and a control group (CG, n = 8) training 3 sessions per week with moderate intensity (6hrs/week). The two groups were assessed at four and six months post-ACLR and the effects of retraining were measured using the following assessments: the functional and the muscular power tests, and the agility T-test. After retraining, the FTG had improved more than the CG in the operated leg in the single leg hop test (+34.64% vs. +10.92%; large effect), the five jump test (+8.87% vs. +5.03%; medium effect), and single leg triple jump (+32.15% vs. +16.05%; medium effect). For the agility T-test, the FTG had larger improvements (+17.26% vs. +13.03%, medium effect) as compared to the CG. For the bilateral power tests, no significant training effects were shown for the two groups in the squat jump (SJ), the counter movement jump (CMJ) and the free arms CMJ (Arm CMJ). On the other hand, the unilateral CMJ test with the injured and the uninjured legs showed a significant increase for the FTG with respect to CG (p < 0.05). The present study introduces a new training modality in rehabilitation after ACLR that results in good recovery of the operated limb along with the contra-lateral leg. This may allow the athletes to reach good functional and strength performance with only two physical training sessions per week, better preparing them for a return to sport activity at 6 months post- ACLR and eventually sparing time for a possible progressive introduction of the sport specific technical training. Key pointsFunctional training (plyometrics, neuromuscular, proprioceptive

  17. The PIN-FORMED (PIN) protein family of auxin transporters

    PubMed Central

    2009-01-01

    Summary The PIN-FORMED (PIN) proteins are secondary transporters acting in the efflux of the plant signal molecule auxin from cells. They are asymmetrically localized within cells and their polarity determines the directionality of intercellular auxin flow. PIN genes are found exclusively in the genomes of multicellular plants and play an important role in regulating asymmetric auxin distribution in multiple developmental processes, including embryogenesis, organogenesis, tissue differentiation and tropic responses. All PIN proteins have a similar structure with amino- and carboxy-terminal hydrophobic, membrane-spanning domains separated by a central hydrophilic domain. The structure of the hydrophobic domains is well conserved. The hydrophilic domain is more divergent and it determines eight groups within the protein family. The activity of PIN proteins is regulated at multiple levels, including transcription, protein stability, subcellular localization and transport activity. Different endogenous and environmental signals can modulate PIN activity and thus modulate auxin-distribution-dependent development. A large group of PIN proteins, including the most ancient members known from mosses, localize to the endoplasmic reticulum and they regulate the subcellular compartmentalization of auxin and thus auxin metabolism. Further work is needed to establish the physiological importance of this unexpected mode of auxin homeostasis regulation. Furthermore, the evolution of PIN-based transport, PIN protein structure and more detailed biochemical characterization of the transport function are important topics for further studies. PMID:20053306

  18. Reconstruction and Application of Protein–Protein Interaction Network

    PubMed Central

    Hao, Tong; Peng, Wei; Wang, Qian; Wang, Bin; Sun, Jinsheng

    2016-01-01

    The protein-protein interaction network (PIN) is a useful tool for systematic investigation of the complex biological activities in the cell. With the increasing interests on the proteome-wide interaction networks, PINs have been reconstructed for many species, including virus, bacteria, plants, animals, and humans. With the development of biological techniques, the reconstruction methods of PIN are further improved. PIN has gradually penetrated many fields in biological research. In this work we systematically reviewed the development of PIN in the past fifteen years, with respect to its reconstruction and application of function annotation, subsystem investigation, evolution analysis, hub protein analysis, and regulation mechanism analysis. Due to the significant role of PIN in the in-depth exploration of biological process mechanisms, PIN will be preferred by more and more researchers for the systematic study of the protein systems in various kinds of organisms. PMID:27338356

  19. Pip pin reliability and design

    NASA Technical Reports Server (NTRS)

    Skyles, Lane P.

    1994-01-01

    Pip pins are used in many engineering applications. Of particular interest to the aerospace industry is their use in various mechanism designs. Many payloads that fly aboard our nation's Space Shuttle have at least one actuated mechanism. Often these mechanisms incorporate pip pins in their design in order to fasten interfacing parts or joints. Pip pins are most often used when an astronaut will have a direct interface with the mechanism. This interfacing can be done during Space Shuttle mission EVA's (ExtraVehicular Activity). The main reason for incorporating pip pins is convenience and their ability to provide a quick release for interfacing parts. However, there are some issues that must be taken into account when using them in a design. These issues include documented failures and quality control problems when using substandard pip pins. A history of pip pins as they relate to the aerospace industry as well as general design features is discussed.

  20. Vortex pinning properties in Fe-chalcogenides

    NASA Astrophysics Data System (ADS)

    Leo, A.; Grimaldi, G.; Guarino, A.; Avitabile, F.; Nigro, A.; Galluzzi, A.; Mancusi, D.; Polichetti, M.; Pace, S.; Buchkov, K.; Nazarova, E.; Kawale, S.; Bellingeri, E.; Ferdeghini, C.

    2015-12-01

    Among the families of iron-based superconductors, the 11-family is one of the most attractive for high field applications at low temperatures. Optimization of the fabrication processes for bulk, crystalline and/or thin film samples is the first step in producing wires and/or tapes for practical high power conductors. Here we present the results of a comparative study of pinning properties in iron-chalcogenides, investigating the flux pinning mechanisms in optimized Fe(Se{}1-xTe x ) and FeSe samples by current-voltage characterization, magneto-resistance and magnetization measurements. In particular, from Arrhenius plots in magnetic fields up to 9 T, the activation energy is derived as a function of the magnetic field, {U}0(H), whereas the activation energy as a function of temperature, U(T), is derived from relaxation magnetization curves. The high pinning energies, high upper critical field versus temperature slopes near critical temperatures, and highly isotropic pinning properties make iron-chalcogenide superconductors a technological material which could be a real competitor to cuprate high temperature superconductors for high field applications.

  1. Development of 3D pseudo pin-by-pin calculation methodology in ANC

    SciTech Connect

    Zhang, B.; Mayhue, L.; Huria, H.; Ivanov, B.

    2012-07-01

    Advanced cores and fuel assembly designs have been developed to improve operational flexibility, economic performance and further enhance safety features of nuclear power plants. The simulation of these new designs, along with strong heterogeneous fuel loading, have brought new challenges to the reactor physics methodologies currently employed in the industrial codes for core analyses. Control rod insertion during normal operation is one operational feature in the AP1000{sup R} plant of Westinghouse next generation Pressurized Water Reactor (PWR) design. This design improves its operational flexibility and efficiency but significantly challenges the conventional reactor physics methods, especially in pin power calculations. The mixture loading of fuel assemblies with significant neutron spectrums causes a strong interaction between different fuel assembly types that is not fully captured with the current core design codes. To overcome the weaknesses of the conventional methods, Westinghouse has developed a state-of-the-art 3D Pin-by-Pin Calculation Methodology (P3C) and successfully implemented in the Westinghouse core design code ANC. The new methodology has been qualified and licensed for pin power prediction. The 3D P3C methodology along with its application and validation will be discussed in the paper. (authors)

  2. Electrically controlled pinning of Dzyaloshinskii-Moriya domain walls

    NASA Astrophysics Data System (ADS)

    Sato, Koji; Tretiakov, Oleg A.

    2016-03-01

    We propose a method to all-electrically control a domain-wall position in a ferromagnetic nanowire with Dzyaloshinskii-Moriya interaction. The strength of this interaction can be controlled by an external electric field, which in turn allows a fine tuning of the pinning potential of a spin-spiral domain wall. It allows to create more mobile pinning sites and can also be advantageous for ultra-low power electronics.

  3. Reconstruction of 137Cs activity in the ocean following the Fukushima Daiichi Nuclear Power Plant Accident

    NASA Astrophysics Data System (ADS)

    Tsumune, Daisuke; Aoyama, Michio; Tsubono, Takaki; Tateda, Yutaka; Misumi, Kazuhiro; Hayami, Hiroshi; Toyoda, Yasuhiro; Maeda, Yoshiaki; Yoshida, Yoshikatsu; Uematsu, Mitsuo

    2014-05-01

    A series of accidents at the Fukushima Dai-ichi Nuclear Power Plant following the earthquake and tsunami of 11 March 2011 resulted in the release of radioactive materials to the ocean by two major pathways, direct release from the accident site and atmospheric deposition. We reconstructed spatiotemporal variability of 137Cs activity in the ocean by the comparison model simulations and observed data. We employed a regional scale and the North Pacific scale oceanic dispersion models, an atmospheric transport model, a sediment transport model, a dynamic biological compartment model for marine biota and river runoff model to investigate the oceanic contamination. Direct releases of 137Cs were estimated for more than 2 years after the accident by comparing simulated results and observed activities very close to the site. The estimated total amounts of directly released 137Cs was 3.6±0.7 PBq. Directly release rate of 137Cs decreased exponentially with time by the end of December 2012 and then, was almost constant. The daily release rate of 137Cs was estimated to be 3.0 x 1010 Bq day-1 by the end of September 2013. The activity of directly released 137Cs was detectable only in the coastal zone after December 2012. Simulated 137Cs activities attributable to direct release were in good agreement with observed activities, a result that implies the estimated direct release rate was reasonable, while simulated 137Cs activities attributable to atmospheric deposition were low compared to measured activities. The rate of atmospheric deposition onto the ocean was underestimated because of a lack of measurements of dose rate and air activity of 137Cs over the ocean when atmospheric deposition rates were being estimated. Observed 137Cs activities attributable to atmospheric deposition in the ocean helped to improve the accuracy of simulated atmospheric deposition rates. Although there is no observed data of 137Cs activity in the ocean from 11 to 21 March 2011, observed data of

  4. Shock characterization of TOAD pins

    SciTech Connect

    Weirick, L.J.; Navarro, N.J.

    1995-08-01

    The purpose of this program was to characterize Time Of Arrival Detectors (TOAD) pins response to shock loading with respect to risetime, amplitude, repeatability and consistency. TOAD pins were subjected to impacts of 35 to 420 kilobars amplitude and approximately 1 ms pulse width to investigate the timing spread of four pins and the voltage output profile of the individual pins. Sets of pins were also aged at 45{degrees}, 60{degrees}, and 80{degrees}C for approximately nine weeks before shock testing at 315 kilobars impact stress. Four sets of pins were heated to 50.2{degrees}C (125{degrees}F) for approximately two hours and then impacted at either 50 or 315 kilobars. Also, four sets of pins were aged at 60{degrees}C for nine weeks and then heated to 50.2{degrees}C before shock testing at 50 and 315 kilobars impact stress, respectively. Particle velocity measurements at the contact point between the stainless steel targets and TOAD pins were made using a Velocity Interferometer System for Any Reflector (VISAR) to monitor both the amplitude and profile of the shock waves.

  5. Shock characterization of toad pins

    SciTech Connect

    Weirick, L.J.; Navarro, M.J.

    1996-05-01

    The purpose of this program was to characterize Time Of Arrival Detectors (TOAD) pins response to shock loading with respect to risetime, amplitude, repeatability and consistency. TOAD pins were subjected to impacts of 35 to 420 kilobars amplitude and approximately 1 ms pulse width to investigate the timing spread of four pins and the voltage output profile of the individual pins. Sets of pins were also aged at 45{degree}, 60{degree} and 80{degree}C for approximately nine weeks before shock testing at 315 kilobars impact stress. Four sets of pins were heated to 50.2{degree}C (125{degree}F) for approximately two hours and then impacted at either 50 or 315 kilobars. Also, four sets of pins were aged at 60{degree}C for nine weeks and then heated to 50.2{degree}C before shock testing at 50 and 315 kilobars impact stress, respectively. Particle velocity measurements at the contact point between the stainless steel targets and TOAD pins were made using a Velocity Interferometer System for Any Reflector (VISAR) to monitor both the amplitude and profile of the shock waves. {copyright} {ital 1996 American Institute of Physics.}

  6. Parentage Reconstruction in Eucalyptus nitens Using SNPs and Microsatellite Markers: A Comparative Analysis of Marker Data Power and Robustness

    PubMed Central

    Telfer, Emily J.; Stovold, Grahame T.; Li, Yongjun; Silva-Junior, Orzenil B.; Grattapaglia, Dario G.; Dungey, Heidi S.

    2015-01-01

    Pedigree reconstruction using molecular markers enables efficient management of inbreeding in open-pollinated breeding strategies, replacing expensive and time-consuming controlled pollination. This is particularly useful in preferentially outcrossed, insect pollinated Eucalypts known to suffer considerable inbreeding depression from related matings. A single nucleotide polymorphism (SNP) marker panel consisting of 106 markers was selected for pedigree reconstruction from the recently developed high-density Eucalyptus Infinium SNP chip (EuCHIP60K). The performance of this SNP panel for pedigree reconstruction in open-pollinated progenies of two Eucalyptus nitens seed orchards was compared with that of two microsatellite panels with 13 and 16 markers respectively. The SNP marker panel out-performed one of the microsatellite panels in the resolution power to reconstruct pedigrees and out-performed both panels with respect to data quality. Parentage of all but one offspring in each clonal seed orchard was correctly matched to the expected seed parent using the SNP marker panel, whereas parentage assignment to less than a third of the expected seed parents were supported using the 13-microsatellite panel. The 16-microsatellite panel supported all but one of the recorded seed parents, one better than the SNP panel, although there was still a considerable level of missing and inconsistent data. SNP marker data was considerably superior to microsatellite data in accuracy, reproducibility and robustness. Although microsatellites and SNPs data provide equivalent resolution for pedigree reconstruction, microsatellite analysis requires more time and experience to deal with the uncertainties of allele calling and faces challenges for data transferability across labs and over time. While microsatellite analysis will continue to be useful for some breeding tasks due to the high information content, existing infrastructure and low operating costs, the multi-species SNP resource

  7. Fuel pin cladding

    DOEpatents

    Vaidyanathan, Swaminathan; Adamson, Martyn G.

    1986-01-01

    An improved fuel pin cladding, particularly adapted for use in breeder reactors, consisting of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel and/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients.

  8. Fuel pin cladding

    DOEpatents

    Vaidyanathan, S.; Adamson, M.G.

    1983-12-16

    An improved fuel pin cladding, particularly adapted for use in breeder reactors, is described which consist of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel an/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients.

  9. Fuel pin cladding

    DOEpatents

    Vaidyanathan, S.; Adamson, M.G.

    1986-01-28

    Disclosed is an improved fuel pin cladding, particularly adapted for use in breeder reactors, consisting of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel and/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients. 2 figs.

  10. Anvil for Flaring PCB Guide Pins

    NASA Technical Reports Server (NTRS)

    Winn, E.; Turner, R.

    1985-01-01

    Spring-loaded anvil results in fewer fractured pins. New anvil for flaring guide pins in printed-circuit boards absorbs approximately 80 percent of press force. As result fewer pins damaged, and work output of flaring press greatly increased.

  11. Reconstruction of the primordial fluctuation spectrum from the five-year WMAP data by the cosmic inversion method with band-power decorrelation analysis

    SciTech Connect

    Nagata, Ryo; Yokoyama, Jun'ichi

    2008-12-15

    The primordial curvature fluctuation spectrum is reconstructed by the cosmic inversion method using the five-year Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background temperature anisotropy. We apply the covariance matrix analysis and decompose the reconstructed spectrum into statistically independent band-powers. The statistically significant deviation from a simple power-law spectrum suggested by the analysis of the first-year data is not found in the five-year data except possibly at one point near the border of the wave number domain where accurate reconstruction is possible.

  12. Quenched pinning and collective dislocation dynamics

    PubMed Central

    Ovaska, Markus; Laurson, Lasse; Alava, Mikko J.

    2015-01-01

    Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely. PMID:26024505

  13. Quenched pinning and collective dislocation dynamics.

    PubMed

    Ovaska, Markus; Laurson, Lasse; Alava, Mikko J

    2015-01-01

    Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely. PMID:26024505

  14. Automated fuel pin loading system

    DOEpatents

    Christiansen, D.W.; Brown, W.F.; Steffen, J.M.

    An automated loading system for nuclear reactor fuel elements utilizes a gravity feed conveyor which permits individual fuel pins to roll along a constrained path perpendicular to their respective lengths. The individual lengths of fuel cladding are directed onto movable transports, where they are aligned coaxially with the axes of associated handling equipment at appropriate production stations. Each fuel pin can be be reciprocated axially and/or rotated about its axis as required during handling steps. The fuel pins are inerted as a batch prior to welding of end caps by one of two disclosed welding systems.

  15. Automated fuel pin loading system

    DOEpatents

    Christiansen, David W.; Brown, William F.; Steffen, Jim M.

    1985-01-01

    An automated loading system for nuclear reactor fuel elements utilizes a gravity feed conveyor which permits individual fuel pins to roll along a constrained path perpendicular to their respective lengths. The individual lengths of fuel cladding are directed onto movable transports, where they are aligned coaxially with the axes of associated handling equipment at appropriate production stations. Each fuel pin can be reciprocated axially and/or rotated about its axis as required during handling steps. The fuel pins are inserted as a batch prior to welding of end caps by one of two disclosed welding systems.

  16. Multi-proxy reconstructions and the power of integration across marine, terrestrial, and freshwater ecosystems. (Invited)

    NASA Astrophysics Data System (ADS)

    Barrett, P. J.

    2011-12-01

    Over the past decade, dendrochronology (tree-ring analysis) techniques have been increasingly applied to growth increments of various bivalve, fish, and coral species. In particular, the use of crossdating ensures that all increments in a dataset have assigned the correct calendar year of formation and that the resulting chronology is exactly placed in time. Such temporal alignment facilitates direct comparisons among chronologies that span diverse taxa and ecosystems, illustrating the pervasive, synchronizing influence of climate from alpine forests to the continental slope. Such an approach can be particularly beneficial to reconstructions in that each species captures climate signals from its unique 'perspective' of life history and habitat. For example, combinations of tree-ring data and chronologies for the long-lived bivalve Pacific geoduck (Panopea generosa) capture substantially more variance in regional sea surface temperatures than either proxy could explain alone. Just as importantly, networks of chronologies spanning multiple trophic levels can help identify climate variables critical to ecosystem functioning, which can then be targeted to generate most biologically relevant reconstructions possible. Along the west coast of North America, fish and bivalve chronologies in combination with records of seabird reproductive success indicate that winter sea-level pressure is closely associated with California Current productivity, which can be hind-cast over the past six centuries using coastal tree-ring chronologies. Thus, multiple proxies not only increase reconstruction skill, but also help isolate climate variables most closely linked to ecosystem structure and functioning.

  17. Multi-proxy reconstructions and the power of integration across marine, terrestrial, and freshwater ecosystems. (Invited)

    NASA Astrophysics Data System (ADS)

    Black, B.

    2013-12-01

    Over the past decade, dendrochronology (tree-ring analysis) techniques have been increasingly applied to growth increments of various bivalve, fish, and coral species. In particular, the use of crossdating ensures that all increments in a dataset have assigned the correct calendar year of formation and that the resulting chronology is exactly placed in time. Such temporal alignment facilitates direct comparisons among chronologies that span diverse taxa and ecosystems, illustrating the pervasive, synchronizing influence of climate from alpine forests to the continental slope. Such an approach can be particularly beneficial to reconstructions in that each species captures climate signals from its unique 'perspective' of life history and habitat. For example, combinations of tree-ring data and chronologies for the long-lived bivalve Pacific geoduck (Panopea generosa) capture substantially more variance in regional sea surface temperatures than either proxy could explain alone. Just as importantly, networks of chronologies spanning multiple trophic levels can help identify climate variables critical to ecosystem functioning, which can then be targeted to generate most biologically relevant reconstructions possible. Along the west coast of North America, fish and bivalve chronologies in combination with records of seabird reproductive success indicate that winter sea-level pressure is closely associated with California Current productivity, which can be hind-cast over the past six centuries using coastal tree-ring chronologies. Thus, multiple proxies not only increase reconstruction skill, but also help isolate climate variables most closely linked to ecosystem structure and functioning.

  18. Pin1 in Neuronal Apoptosis

    PubMed Central

    Becker, Esther B.E.; Bonni, Azad

    2009-01-01

    While the role of the prolyl isomerase Pin1 in dividing cells has long been recognized, Pin1’s function in postmitotic neurons is poorly understood. We have identified a novel mechanism by which Pin1 mediates activation of the mitochondrial cell death machinery specifically in neurons. This perspective presents a sophisticated signaling pathway that triggers neuronal apoptosis upon JNK-mediated phosphorylation of the BH3-only protein BIMEL at serine 65. Pin1 is enriched at the mitochondria in neurons together with BIMEL and components of a neuron-specific JNK signaling complex and functions as a molecular switch that couples the phosphorylation of BIMEL by JNK to apoptosis specifically in neurons. We discuss how these findings relate to our understanding of the development of the nervous system and the pathogenesis of neurologic disorders. PMID:17568190

  19. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, David J.

    1987-01-01

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pin passageway extending through the assembly.

  20. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, David J.

    1987-02-03

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pin passageway extending through the assembly.

  1. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, D.J.

    1984-05-30

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pins passageway extending through the assembly.

  2. Simulation of the Vortex Dynamics in a Real Pinning Landscape of YBa2 Cu3 O7 -δ Coated Conductors

    NASA Astrophysics Data System (ADS)

    Sadovskyy, I. A.; Koshelev, A. E.; Glatz, A.; Ortalan, V.; Rupich, M. W.; Leroux, M.

    2016-01-01

    The ability of high-temperature superconductors (HTSs) to carry very large currents with almost no dissipation makes them irreplaceable for high-power applications. The development and further improvement of HTS-based cables require an in-depth understanding of the superconducting vortex dynamics in the presence of complex pinning landscapes. We present a critical current analysis of a real HTS sample in a magnetic field by combining state-of-the-art large-scale Ginzburg-Landau simulations with reconstructive three-dimensional scanning-transmission-electron-microscopy tomography of the pinning landscape in Dy-doped YBa2 Cu3 O7 -δ . This methodology provides a unique look at the vortex dynamics in the presence of a complex pinning landscape responsible for the high-current-carrying-capacity characteristic of commercial HTS wires. Our method demonstrates very good functional and quantitative agreement of the critical current between simulation and experiment, providing a new predictive tool for HTS wire designs.

  3. Pin-Type Gas Cooled Reactor for Nuclear Electric Propulsion

    NASA Astrophysics Data System (ADS)

    Wright, Steven A.; Lipinski, Ronald J.

    2003-01-01

    This paper describes a point design for a pin-type Gas-Cooled Reactor concept that uses a fuel pin design similar to the SP100 fuel pin. The Gas-Cooled Reactor is designed to operate at 100 kWe for 7 years plus have a reduced power mode of 20% power for a duration of 5 years. The power system uses a gas-cooled, UN-fueled, pin-type reactor to heat He/Xe gas that flows directly into a recuperated Brayton system to produce electricity. Heat is rejected to space via a thermal radiator that unfolds in space. The reactor contains approximately 154 kg of 93.15 % enriched UN in 313 fuel pins. The fuel is clad with rhenium-lined Nb-1Zr. The pressures vessel and ducting are cooled by the 900 K He/Xe gas inlet flow or by thermal radiation. This permits all pressure boundaries to be made of superalloy metals rather than refractory metals, which greatly reduces the cost and development schedule required by the project. The reactor contains sufficient rhenium (a neutron poison) to make the reactor subcritical under water immersion accidents without the use of internal shutdown rods. The mass of the reactor and reflectors is about 750 kg.

  4. Small pinning points increase grounding-line sensitivity

    NASA Astrophysics Data System (ADS)

    Favier, Lionel; Pattyn, Frank; Berger, Sophie; Drews, Reinhard

    2016-04-01

    Initialising prognostic simulations of outlet glaciers relies on geometry and surface velocity, from which data assimilation methods rectify poorly known parameters such as ice stiffness or basal slipperiness. Stemming from the contact between ice shelves and submarine topographic highs, pinning points impact both ice velocity and stiffness but, wherever they are small enough, they can easily be overlooked by satellite observations. Here, we use the ice-sheet model BISICLES to investigate the future ice dynamical behaviour of two neighbouring outlet glaciers in Dronning Maud Land, i.e., Hansenbreen and West Raghnild glacier. The latter is buttressed by a previously uncharted pinning point at the ice shelf front while both are separated by an ice promontory. We also reconstruct ice velocity and geometry fields including the pinning point, which is absent from Antarctic-wide datasets, from data collected on site. The model is initialised with three combinations of ice geometry and stiffness, (i) with or (ii) without the pinning point influence in the assimilation procedure, and (iii) being a variant of (i) but starting with unpinning. We explore two sub-ice shelf melting scenarios of three amplitudes, and two weertmann-type sliding law exponents for each initialisation. The results show the future unstable retreat of Hansenbreen, moderately affected by unpinning. However, ignoring the pinning point in data assimilation overstiffens the ice shelf and highly decreases the timing of the retreat. This study stresses the need of accurate bathymetry and ice velocity, as the current datasets that disregard pinning points tend to stabilise marine sectors of the East Antarctic ice sheet, hence affecting sea-level rise predictions.

  5. Prolyl isomerase Pin1 regulated signaling pathway revealed by Pin1 +/+ and Pin1 -/- mouse embryonic fibroblast cells.

    PubMed

    Huang, Guo-Liang; Qiu, Jin-Hua; Li, Bin-Bin; Wu, Jing-Jing; Lu, Yan; Liu, Xing-Yan; He, Zhiwei

    2013-10-01

    Pin1 (peptidylprolyl cis/trans isomerase, NIMA-interacting 1) plays a key role in a number of diseases including cancer and Alzheimer disease. Previous studies have identified a wide range of phosphoproteins as Pin1 substrates. Related pathways were analyzed separately. The aim of this study was to provide a comprehensive picture involving Pin1 regulation. A genome-wide mRNA expression microarray was carried out using the RNA isolation from Pin1 (+/+) and Pin1 (-/-) mouse embryonic fibroblast (MEF) cells. Signaling pathways regulated by Pin1 were analyzed with the utility of KEGG pathway and GO annotation. An expression pattern regulated by Pin1 was revealed. A total of 606 genes, 375 being up-regulated and 231 down-regulated, were differentially expressed when comparing Pin1 +/+ to Pin1 -/- MEF cells. Totally 48 pathways were shown to be regulated by Pin1 expression in KEGG pathway analysis. In the GO annotation system, 19 processes on biological processes, 15 processes on cellular components, and 18 processes on molecular functions were found to be in the regulation of Pin1 expression. Pathways related to immune system and cancer showed most significant association with Pin1 regulation. Pin1 is an important regulator in a wide range of signaling pathways that were related to immune system and cancer. PMID:23563987

  6. Thermoacoustic pin stacks. Summary report

    SciTech Connect

    Keolian, R.M.

    1994-07-06

    The construction and testing of a new stack geometry for thermoacoustic engines, called a pin stack, has been started. The stack is at the heart of a class of heat engines that use sound to deliver refrigeration, or use a temperature difference to generate sound. Calculations show that the pin stack should make useful improvements in engine efficiency. About 2000 wires will be hand sewn in a hexagonal lattice between the hot and cold heat exchangers in a sound source using low pressure neon gas between 300 K and 77 K. Thermoacoustics, Refrigeration, Acoustic source, Heat pump.

  7. 3D reconstruction and particle acceleration properties of Coronal Shock Waves During Powerful Solar Particle Events

    NASA Astrophysics Data System (ADS)

    Plotnikov, Illya; Vourlidas, Angelos; Tylka, Allan J.; Pinto, Rui; Rouillard, Alexis; Tirole, Margot

    2016-07-01

    Identifying the physical mechanisms that produce the most energetic particles is a long-standing observational and theoretical challenge in astrophysics. Strong pressure waves have been proposed as efficient accelerators both in the solar and astrophysical contexts via various mechanisms such as diffusive-shock/shock-drift acceleration and betatron effects. In diffusive-shock acceleration, the efficacy of the process relies on shock waves being super-critical or moving several times faster than the characteristic speed of the medium they propagate through (a high Alfven Mach number) and on the orientation of the magnetic field upstream of the shock front. High-cadence, multipoint imaging using the NASA STEREO, SOHO and SDO spacecrafts now permits the 3-D reconstruction of pressure waves formed during the eruption of coronal mass ejections. Using these unprecedented capabilities, some recent studies have provided new insights on the timing and longitudinal extent of solar energetic particles, including the first derivations of the time-dependent 3-dimensional distribution of the expansion speed and Mach numbers of coronal shock waves. We will review these recent developments by focusing on particle events that occurred between 2011 and 2015. These new techniques also provide the opportunity to investigate the enigmatic long-duration gamma ray events.

  8. Accelerating an Ordered-Subset Low-Dose X-Ray Cone Beam Computed Tomography Image Reconstruction with a Power Factor and Total Variation Minimization

    PubMed Central

    Huang, Hsuan-Ming; Hsiao, Ing-Tsung

    2016-01-01

    In recent years, there has been increased interest in low-dose X-ray cone beam computed tomography (CBCT) in many fields, including dentistry, guided radiotherapy and small animal imaging. Despite reducing the radiation dose, low-dose CBCT has not gained widespread acceptance in routine clinical practice. In addition to performing more evaluation studies, developing a fast and high-quality reconstruction algorithm is required. In this work, we propose an iterative reconstruction method that accelerates ordered-subsets (OS) reconstruction using a power factor. Furthermore, we combine it with the total-variation (TV) minimization method. Both simulation and phantom studies were conducted to evaluate the performance of the proposed method. Results show that the proposed method can accelerate conventional OS methods, greatly increase the convergence speed in early iterations. Moreover, applying the TV minimization to the power acceleration scheme can further improve the image quality while preserving the fast convergence rate. PMID:27073853

  9. Cryogenically cooled detector pin mount

    SciTech Connect

    Hunt, Jr., William E; Chrisp, Michael P

    2014-06-03

    A focal plane assembly facilitates a molybdenum base plate being mounted to another plate made from aluminum. The molybdenum pin is an interference fit (press fit) in the aluminum base plate. An annular cut out area in the base plate forms two annular flexures.

  10. Lightning Pin Injection Testing on MOSFETS

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.; Koppen, Sandra V.; Mielnik, John J.; Vaughan, Roger K.; Wysocki, Philip F.; Celaya, Jose R.; Saha, Sankalita

    2009-01-01

    Lightning transients were pin-injected into metal-oxide-semiconductor field-effect transistors (MOSFETs) to induce fault modes. This report documents the test process and results, and provides a basis for subsequent lightning tests. MOSFETs may be present in DC-DC power supplies and electromechanical actuator circuits that may be used on board aircraft. Results show that unprotected MOSFET Gates are susceptible to failure, even when installed in systems in well-shielded and partial-shielded locations. MOSFET Drains and Sources are significantly less susceptible. Device impedance decreased (current increased) after every failure. Such a failure mode may lead to cascading failures, as the damaged MOSFET may allow excessive current to flow through other circuitry. Preliminary assessments on a MOSFET subjected to 20-stroke pin-injection testing demonstrate that Breakdown Voltage, Leakage Current and Threshold Voltage characteristics show damage, while the device continues to meet manufacturer performance specifications. The purpose of this research is to develop validated tools, technologies, and techniques for automated detection, diagnosis and prognosis that enable mitigation of adverse events during flight, such as from lightning transients; and to understand the interplay between lightning-induced surges and aging (i.e. humidity, vibration thermal stress, etc.) on component degradation.

  11. Improved shock-detecting pin arrangement

    SciTech Connect

    Erskine, D.J.

    1996-05-01

    Shockwave speeds are often measured by comparing arrival times at the tips of electrical shorting pins in a hexagonal array over two elevations (called up and down). In the conventional arrangement, the center pin is solely responsible for measuring the curvature of the wavefront. Without this datum the shock speed cannot be precisely determined. In some experiments this pin fail frequently enough to be a problem. We report a simple rearrangement between up and down designated pins which eliminates the critical reliance on a single pin. {copyright} {ital 1996 American Institute of Physics.}

  12. Pinning control of chimera states

    NASA Astrophysics Data System (ADS)

    Gambuzza, Lucia Valentina; Frasca, Mattia

    2016-08-01

    The position of the coherent and incoherent domain of a chimera state in a ring of nonlocally coupled oscillators is strongly influenced by the initial conditions, making nontrivial the problem of confining them in a specific region of the structure. In this paper we propose the use of spatial pinning to induce a chimera state where the nodes belonging to one domain, either the coherent or the incoherent, are fixed by the control action. We design two different techniques according to the dynamics to be forced in the region of pinned nodes, and validate them on FitzHugh-Nagumo and Kuramoto oscillators. Furthermore, we introduce a suitable strategy to deal with the effects of finite size in small structures.

  13. Pinning synchronization of a mobile agent network

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Sun, You-xian

    2009-11-01

    We investigate the problem of controlling a group of mobile agents in a plane in order to move them towards a desired orbit via pinning control, in which each agent is associated with a chaotic oscillator coupled with those of neighboring agents, and the pinning strategy is to have the common linear feedback acting on a small fraction of agents by random selection. We explore the effects of the pinning probability, feedback gains and agent density in the pinning synchronization of a mobile agent network under a fast-switching constraint, and perform numerical simulations for validation. In particular, we show that there exists a critical pinning density for network synchronization with an unbounded region: above the threshold, the dynamical network can be controlled by pinning; below it, anarchy prevails. And for the network with a single bounded synchronization region, pinning control has little effect as regards enhancing network synchronizability.

  14. Alignment Pins for Assembling and Disassembling Structures

    NASA Technical Reports Server (NTRS)

    Campbell, Oliver C.

    2008-01-01

    Simple, easy-to-use, highly effective tooling has been devised for maintaining alignment of bolt holes in mating structures during assembly and disassembly of the structures. The tooling was originally used during removal of a body flap from the space shuttle Atlantis, in which misalignments during removal of the last few bolts could cause the bolts to bind in their holes. By suitably modifying the dimensions of the tooling components, the basic design of the tooling can readily be adapted to other structures that must be maintained in alignment. The tooling includes tapered, internally threaded alignment pins designed to fit in the bolt holes in one of the mating structures, plus a draw bolt and a cup that are used to install or remove each alignment pin. In preparation for disassembly of two mating structures, external supports are provided to prevent unintended movement of the structures. During disassembly of the structures, as each bolt that joins the structures is removed, an alignment pin is installed in its place. Once all the bolts have been removed and replaced with pins, the pins maintain alignment as the structures are gently pushed or pulled apart on the supports. In assembling the two structures, one reverses the procedure described above: pins are installed in the bolt holes, the structures are pulled or pushed together on the supports, then the pins are removed and replaced with bolts. The figure depicts the tooling and its use. To install an alignment pin in a bolt hole in a structural panel, the tapered end of the pin is inserted from one side of the panel, the cup is placed over the pin on the opposite side of the panel, the draw bolt is inserted through the cup and threaded into the pin, the draw bolt is tightened to pull the pin until the pin is seated firmly in the hole, then the draw bolt and cup are removed, leaving the pin in place. To remove an alignment pin, the cup is placed over the pin on the first-mentioned side of the panel, the draw

  15. SU-F-18C-02: Evaluations of the Noise Power Spectrum of a CT Iterative Reconstruction Technique for Radiation Therapy

    SciTech Connect

    Dolly, S; Chen, H; Anastasio, M; Mutic, S; Li, H

    2014-06-15

    Purpose: To quantitatively assess the noise power spectrum (NPS) of the new, commercially released CT iterative reconstruction technique, iDose{sup 4} from Philips, to compare it with filtered back-projection techniques (FBP), and to provide clinical practice suggestions for radiation therapy. Methods: A uniform phantom was CT imaged with 120kVp tube potential over a range of mAs (250-3333). The image sets were reconstructed using two reconstruction algorithms (FBP and iDose{sup 4} with noise reduction levels 1, 3, and 6) and three reconstruction filters (standard B, smooth A, and sharp C), after which NPS variations were analyzed and compared on region of interest (ROI) sizes (16×16 to 128×128 pixels), ROI radii (0–65 mm), reconstruction algorithms, reconstruction filters, and mAs. Results: The NPS magnitude and shape depended considerably on ROI size and location for both reconstruction algorithms. Regional noise variance became more stationary as ROI size decreased, minimizing NPS artifacts. The optimal 32×32-pixel ROI size balanced the trade-off between stationary noise and adequate sampling. NPS artifacts were greatest at the center of reconstruction space and decreased with increasing ROI distance from the center. The optimal ROI position was located near the phantom's radial midpoint (∼40mm). For sharper filters, the NPS magnitude and the maximum magnitude frequency increased. Higher dose scans yielded lower NPS magnitudes for both reconstruction algorithms and all filters. Compared to FBP, the iDose{sup 4} algorithm reduced the NPS magnitude while preferentially reducing noise at mid-range spatial frequencies, altering noise texture. This reduction was more significant with increasing iDose{sup 4} noise reduction level. Conclusion: Compared to pixel standard deviation, NPS has greater clinical potential for task-based image quality assessment, describing both the magnitude and spatial frequency characteristics of image noise. While iDose{sup 4

  16. Pin Wire Coating Trip Report

    SciTech Connect

    Spellman, G P

    2004-03-18

    A meeting to discuss the current pin wire coating problems was held at the Reynolds plant in Los Angeles on 2MAR04. The attendance list for Reynolds personnel is attached. there was an initial presentation which gave a brief history and the current status of pin wire coating at Reynolds. There was a presentation by Lori Primus on the requirements and issues for the coating. There was a presentation by Jim Smith of LANL on the chemistry and to some extent process development done to date. There was a long session covering what steps should be taken in the short term and, to a lesser extent, the long term. The coating currently being used is a blend of two polymers, polyethersulfone and polyparabanic acid (PPA) and some TiO2 filler. This system was accepted and put into production when the pin wire coating was outsourced to another company in 1974. When that company no longer was interested, the wire coating was brought in-house to Reynolds. At that time polyparabanic acid was actually a commercial product available from Exxon under the trade name Tradlon. However, it appears that the material used at Reynolds was synthesized locally. Also, it appears that a single large batch was synthesized in that time period and used up to 1997 when the supply ran out. The reason for the inclusion of TiO2 is not known although it does act as a rheological thickener. However, a more controlled thickening can be obtained with materials such as fumed silica. This material would have less likelihood of causing point imperfections in the coatings. Also, the mixing technique being used for all stages of the process is a relatively low shear ball mill process and the author recommends a high shear process such as a three roll paint mill, at least for the final mixing. Since solvent is added to the powder at Reynolds, it may be that they need to have the paint mill there.

  17. Evaluation of Wear between Pin and Bush in Roller Chain

    NASA Astrophysics Data System (ADS)

    Noguchi, Shoji; Yoshiba, Hideaki; Nakayama, Satoshi; Kanada, Tohru

    A roller chain is a typical machine element used in bicycles, motorcycles and many other devices for power transmission. The life of a roller chain is determined by elongation. As a rule of thumb, a chain begins to skip cogs on the sprocket wheel when the percentage of elongation reaches approximately 3%. Mechanical wear between pins and bushes causes elongation of the roller chain. However, research on the evaluation of wear of the roller chain is rare and the achievement is unstated. We describe the following initiatives in the study of wear between pins and bushes of a roller chain: (1) development of a wear tester using only two chain links, (2) establishment of a specific evaluation method using a roundness tester, and (3) causal explanation of non-uniform wear using the finite-element method (FEM). The experimental results show that pins and bushes are not in contact at the centerline, and that wear occurs exclusively at the tips of the pins owing to the bending deformation under the condition of tensile load.

  18. Tool Blunts Cotter Pin Legs for Safety

    NASA Technical Reports Server (NTRS)

    Stein, J. A.; Helble, D. R.

    1982-01-01

    Jaws on new insertion tool contain upset point and anvil. Point forces cotter-pin legs into loop as it engages anvil. Cotter pin before insertion consists of loop and straight shaft composed of two legs welded together as tips. After insertion, welded legs have been shaped into loop. Tool used to prevent bent loose ends of cotter pins from scratching workers' fingers or cutting and entangling wires.

  19. Magnetic pinning in superconductor-ferromagnet multilayers

    SciTech Connect

    Bulaevskii, L. N.; Chudnovsky, E. M.; Maley, M. P.

    2000-05-01

    We argue that superconductor/ferromagnet multilayers of nanoscale period should exhibit strong pinning of vortices by the magnetic domain structure in magnetic fields below the coercive field when ferromagnetic layers exhibit strong perpendicular magnetic anisotropy. The estimated maximum magnetic pinning energy for single vortex in such a system is about 100 times larger than the pinning energy by columnar defects. This pinning energy may provide critical currents as high as 10{sup 6}-10{sup 7} A/cm{sup 2} at high temperatures (but not very close to T{sub c}) at least in magnetic fields below 0.1 T. (c) 2000 American Institute of Physics.

  20. Improved shock-detection pin arrangement

    SciTech Connect

    Erskine, D.J.

    1995-08-01

    Shockwave speeds are often measured by comparing arrival times at the tips of electrical shorting pins in a hexagonal array over two elevations (called up and down). In the conventional arrangement, the center pin is solely responsible for measuring the curvature of the wavefront. Without this datum the shock speed cannot be precisely determined. In some experiments this pin fail frequently enough to be a problem. We report a simple rearrangement between up and down designated pins which eliminates the critical reliance on a single.

  1. Heat Exchanger With Internal Pin Elements

    DOEpatents

    Gerstmann, Joseph; Hannon, Charles L.

    2004-01-13

    A heat exchanger/heater comprising a tubular member having a fluid inlet end, a fluid outlet end and plurality of pins secured to the interior wall of the tube. Various embodiments additionally comprise a blocking member disposed concentrically inside the pins, such as a core plug or a baffle array. Also disclosed is a vapor generator employing an internally pinned tube, and a fluid-heater/heat-exchanger utilizing an outer jacket tube and fluid-side baffle elements, as well as methods for heating a fluid using an internally pinned tube.

  2. Fabrication of FFTF fuel pin wire wrap

    SciTech Connect

    Epperson, E.M.

    1980-06-01

    Lateral spacing between FFTF fuel pins is required to provide a passageway for the sodium coolant to flow over each pin to remove heat generated by the fission process. This spacing is provided by wrapping each fuel pin with type 316 stainless steel wire. This wire has a 1.435mm (0.0565 in.) to 1.448mm (0.0570 in.) diameter, contains 17 +- 2% cold work and was fabricated and tested to exacting RDT Standards. About 500 kg (1100 lbs) or 39 Km (24 miles) of fuel pin wrap wire is used in each core loading. Fabrication procedures and quality assurance tests are described.

  3. Update on PIN or Signature

    NASA Astrophysics Data System (ADS)

    Matyas, Vashek

    We promised a year back some data on the experiment that we ran with chip and PIN. If you recall, it was the first phase that we reported on here last year, where we used the University bookstore, and two PIN pads, one with very solid privacy shielding, the other one without any. We ran 17 people through the first one, 15 people through the second one, and we also had the students do, about half of them forging the signature, half of them signing their own signature, on the back of the card that is used for purchasing books, or whatever.We had a second phase of the experiment, after long negotiations, and very complicated logistics, with a supermarket in Brno where we were able to do anything that we wanted through the experiment for five hours on the floor, with only the supermarket manager, the head of security, and the camera operators knowing about the experiment. So the shop assistants, the ground floor security, everybody basically on the floor, did not know about the experiment. That was one of the reasons why the supermarket, or management, agreed to take part, they wanted to control their own internal security procedures.

  4. Replacement of split-pin assemblies in nuclear reactors

    SciTech Connect

    Nee, J.D.; Green, R.A.

    1989-12-12

    This patent describes a pin-insertion/torque tool for the replacement of old split-pin assemblies. Each of the new split-pin assemblies including a new split-pin having times and a new nut for securing the new split pin in the guide tube, a new nut being inserted in the guide tube in position to receive a split pin. The the pin-insertion/torque tool including a blade means for engaging a new split pin with the blade with the tines of the new split pins straddling the blade, means, connected to the blade, for advancing the split-pin into the guide tube into threading engagement with the new nut positioned to receive a new split pin and means, to be connected to the nut for securing the new nut onto the new split pin while the split pin is engaged by the blade.

  5. Retrospective reconstruction of Ioidne-131 distribution at the Fukushima Daiichi Nuclear Power Plant accident by analysis of Ioidne-129

    NASA Astrophysics Data System (ADS)

    Matsuzaki, Hiroyuki; Muramatsu, Yasuyuki; Toyama, Chiaki; Ohno, Takeshi; Kusuno, Haruka; Miyake, Yasuto; Honda, Maki

    2014-05-01

    Among various radioactive nuclides emitted from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Iodine-131 displayed high radioactivity just after the accident. Moreover if taken into human body, Iodine-131 concentrates in the thyroid and may cause the thyroid cancer. The recognition about the risk of Iodine-131 dose originated from the experience of the Chernobyl accident based on the epidemiological study [1]. It is thus important to investigate the detailed deposition distribution of I-131 to evaluate the radiation dose due to I-131 and watch the influence on the human health. However I-131 decays so rapidly (half life = 8.02 d) that it cannot be detected several months after the accident. At the recognition of the risk of I-131 on the Chernobyl occasion, it had gone several years after the accident. The reconstruction of I-131 distribution from Cs-137 distribution was not successful because the behavior of iodine and cesium was different because they have different chemical properties. Long lived radioactive isotope I-129 (half life = 1.57E+7 yr,), which is also a fission product as well as I-131, is ideal proxy for I-131 because they are chemically identical. Several studies had tried to quantify I-129 in 1990's but the analytical technique, especially AMS (Accelerator Mass Spectrometry), had not been developed well and available AMS facility was limited. Moreover because of the lack of enough data on I-131 just after the accident, the isotopic ratio I-129/I-131 of the Chernobyl derived iodine could not been estimated precisely [2]. Calculated estimation of the isotopic ratio showed scattered results. On the other hand, at the FDNPP accident detailed I-131 distribution is going to be successfully reconstructed by the systematical I-129 measurements by our group. We measured soil samples selected from a series of soil collection taken from every 2 km (or 5km, in the distant area) meshed region around FDNPP conducted by the Japanese Ministry of

  6. Failure Analysis of Electrical Pin Connectors

    NASA Technical Reports Server (NTRS)

    Newman, John A.; Baughman, James M.; Smith, Stephen W.; Herath, Jeffrey A.

    2008-01-01

    A study was initiated to determine the root cause of failure for circuit board electrical connection pins that failed during vibRatory testing. The circuit board is part of an unmanned space probe, and the vibratory testing was performed to ensure component survival of launch loading conditions. The results of this study show that the pins failed as a result of fatigue loading.

  7. Pin1 as an anticancer drug target.

    PubMed

    Xu, Guoyan G; Etzkorn, Felicia A

    2009-09-01

    Pin1 specifically catalyzes the cis/trans isomerization of phospho-Ser/Thr-Pro bonds and plays an important role in many cellular events through the effects of conformational change on the function of its biological substrates, including cell division cycle 25 C (Cdc25C), c-Jun and p53. Pin1 is overexpressed in many human cancer tissues, including breast, prostate and lung cancer. Its expression correlates with cyclin D1 levels, which contribute to cell transformation. Overexpression of Pin1 promotes tumor growth, while inhibition of Pin1 causes tumor cell apoptosis. Pin1 plays an important role in oncogenesis and therefore may serve as an effective anticancer target. Many inhibitors of Pin1 have been discovered, including several classes of designed inhibitors (alkene isosteres, reduced amides, indanyl ketones) and natural products (juglone, pepticinnamin E analogues, PiB and its derivatives obtained from a library screen). Pin1 inhibitors could be used as a novel type of anticancer drug by blocking cell cycle progression. Therefore, Pin1 represents a new diagnostic and therapeutic anticancer drug target. PMID:19890497

  8. Pinning impulsive control algorithms for complex network

    SciTech Connect

    Sun, Wen; Lü, Jinhu; Chen, Shihua; Yu, Xinghuo

    2014-03-15

    In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms.

  9. Stifness Of A Flux-Pinned Virtual Structure For Modular Spacecraft

    NASA Astrophysics Data System (ADS)

    Shoer, J.; Peck, M.

    We propose that modular spacecraft be constructed with interfaces consisting of combinations of magnets and Type II superconductors, establishing a non-contacting interaction between modules via magnetic flux pinning. This stable field interaction allows fractionated or modular spacecraft to fix their relative positions and orientations in a passive, virtual structure without mechanical connection, active control, or power expenditure. We report an experiment that investigates the mechanical properties of this magnetostatic interaction by finding the linear restoring forces and torques on a flux-pinned magnet and superconductor simultaneously in 6DOF for small displacements from a static equilibrium. Our results indicate that flux pinning is promising for modular spacecraft assembly and station-keeping applications, providing mechanical stiffnesses over 200 N/m at small (5 mm) magnet-superconductor separations and potentially useful nonzero stiffnesses at larger (over 3 cm) separations, with significant structural damping. We find that increasing the magnetic flux density at the superconductor surface strengthens the flux-pinning forces, suggesting that higher stiffness can be obtained over larger distances by increasing or focusing the pinned magnetic field. Still larger separations will be possible with other superconduc- tors, particularly single-domain superconductors, which show evidence of flux pinning up to a separation of 7 cm or more. Related experiments may be used in the future for performance verification of flux-pinning spacecraft systems.

  10. Pin-Retraction Mechanism On Quick-Release Cover

    NASA Technical Reports Server (NTRS)

    Macmartin, Malcolm

    1994-01-01

    Quick-release cover includes pin-retraction mechanism releasing cover quickly from lower of two sets of pin connections holding cover. Cover released at top by pulling lever as described in "Lever-Arm Pin Puller" (NPO-18788). Removal of cover begins when technician or robot pulls upper-pin-release lever. Cover swings downward until tabs on lower pins are pulled through slots in their receptacles. Lower pins are then free.

  11. The Mean-Field Flux Pinning Theory

    NASA Astrophysics Data System (ADS)

    Stejic, George

    We develop the Mean-Field Flux Pinning Theory, designed to model the flux line lattice (FLL) as it interacts with itself, the flux pinning centers and the geometry of the superconductor. Like other mean-field theories, the mean-field flux pinning theory does not attempt to model the FLL completely. Instead, it utilizes a simplified model for the FLL, termed the mean-field FLL, in which the FLL is modelled as a continuous vector field rather than as discrete fluxons as in other theories. By so doing, the interactions of the FLL are greatly simplified and more easily modelled. One application of the mean-field flux pinning theory is to predict J_{c} from microstructural data, which we use to determine the optimal Nb-Ti microstructures with (1) alpha -Ti pinning centers and (2) Nb pinning centers. The microstructure is modelled on a grid in which the local values of T_{c} and kappa reflect the spatial distribution of the pinning centers and the superconductor. Using this model, we solve the G-L equations and calculate the pinning potential defined as the vortex free energy as a function of position. We conclude that the ideal Nb-Ti microstructure with alpha-Ti pinning centers would require 40 volume percent of alpha -Ti and have 6nm thick pinning centers. In the Nb pinning center case, the ideal microstructure requires 50 volume percent of Nb and would have 6nm pinning centers. Another application for the mean-field flux pinning theory is to model the FLL as it interacts with the penetrating magnetic fields within lambda of the superconducting surface. Using this theory, we study the effects of sample geometry on the FLL and J _{c} for the thin film geometry. We find that the FLL becomes increasingly distorted as the film thickness is reduced and that J_{c } increases sharply for dimensions less that lambda. These predictions are experimentally evaluated in Nb-Ti thin films. Our results show that J_{c} values as high as 1/3 of J_{d} and a strong orientational

  12. COBRA-PI: an extension of the COBRA-3M code dynamically dimensioned to accept pin bundles of any size. [LMFBR

    SciTech Connect

    Froehle, P.H.; Bauer, T.H.

    1983-03-28

    COBRA, in general, performs a thermal-hydraulic analysis of an actual pin bundle by subdividing the bundle cross-section into coolant subchannels, pin sectors, duct wall sectors. Its calculation includes heat convected axially upward through coolant mass flow, heat flow between pin sectors and adjoining subchannels, and heat and mass flow between coolant subchannels. COBRA-3M is a version of COBRA built for LMFBR applications, that includes a sophisticated thermal model of fuel pins and duct wall. COBRA-3M that can explicitly model a wider variety of pin bundle configurations than 3M would allow and includes significant improvements to its thermal modeling. COBRA-PI is currently being used for thermal-hydraulic analysis of hypothetical LMFBR accident transients in both power and flow. Pin bundles currently being analyzed explicitly range from 7 to 37 pins of axial lengths ranging from approx. 0.3-2.0 meters.

  13. Electroanalytical devices with pins and thread.

    PubMed

    Glavan, Ana C; Ainla, Alar; Hamedi, Mahiar M; Fernández-Abedul, M Teresa; Whitesides, George M

    2016-01-01

    This work describes the adaptive use of conventional stainless steel pins-used in unmodified form or coated with carbon paste-as working, counter, and quasi-reference electrodes in electrochemical devices fabricated using cotton thread or embossed omniphobic R(F) paper to contain the electrolyte and sample. For some applications, these pin electrodes may be easier to modify and use than printed electrodes, and their position and orientation can be changed as needed. Electroanalytical devices capable of multiplex analysis (thread-based arrays or 96-well plates) were easily fabricated using pins as electrodes in either thread or omniphobic R(F) paper. PMID:26549661

  14. SU-E-J-147: Monte Carlo Study of the Precision and Accuracy of Proton CT Reconstructed Relative Stopping Power Maps

    SciTech Connect

    Dedes, G; Asano, Y; Parodi, K; Arbor, N; Dauvergne, D; Testa, E; Letang, J; Rit, S

    2015-06-15

    Purpose: The quantification of the intrinsic performances of proton computed tomography (pCT) as a modality for treatment planning in proton therapy. The performance of an ideal pCT scanner is studied as a function of various parameters. Methods: Using GATE/Geant4, we simulated an ideal pCT scanner and scans of several cylindrical phantoms with various tissue equivalent inserts of different sizes. Insert materials were selected in order to be of clinical relevance. Tomographic images were reconstructed using a filtered backprojection algorithm taking into account the scattering of protons into the phantom. To quantify the performance of the ideal pCT scanner, we study the precision and the accuracy with respect to the theoretical relative stopping power ratios (RSP) values for different beam energies, imaging doses, insert sizes and detector positions. The planning range uncertainty resulting from the reconstructed RSP is also assessed by comparison with the range of the protons in the analytically simulated phantoms. Results: The results indicate that pCT can intrinsically achieve RSP resolution below 1%, for most examined tissues at beam energies below 300 MeV and for imaging doses around 1 mGy. RSP maps accuracy of less than 0.5 % is observed for most tissue types within the studied dose range (0.2–1.5 mGy). Finally, the uncertainty in the proton range due to the accuracy of the reconstructed RSP map is well below 1%. Conclusion: This work explores the intrinsic performance of pCT as an imaging modality for proton treatment planning. The obtained results show that under ideal conditions, 3D RSP maps can be reconstructed with an accuracy better than 1%. Hence, pCT is a promising candidate for reducing the range uncertainties introduced by the use of X-ray CT alongside with a semiempirical calibration to RSP.Supported by the DFG Cluster of Excellence Munich-Centre for Advanced Photonics (MAP)

  15. Molecular pedigree reconstruction and estimation of evolutionary parameters in a wild Atlantic salmon river system with incomplete sampling: a power analysis

    PubMed Central

    2014-01-01

    Background Pedigree reconstruction using genetic analysis provides a useful means to estimate fundamental population biology parameters relating to population demography, trait heritability and individual fitness when combined with other sources of data. However, there remain limitations to pedigree reconstruction in wild populations, particularly in systems where parent-offspring relationships cannot be directly observed, there is incomplete sampling of individuals, or molecular parentage inference relies on low quality DNA from archived material. While much can still be inferred from incomplete or sparse pedigrees, it is crucial to evaluate the quality and power of available genetic information a priori to testing specific biological hypotheses. Here, we used microsatellite markers to reconstruct a multi-generation pedigree of wild Atlantic salmon (Salmo salar L.) using archived scale samples collected with a total trapping system within a river over a 10 year period. Using a simulation-based approach, we determined the optimal microsatellite marker number for accurate parentage assignment, and evaluated the power of the resulting partial pedigree to investigate important evolutionary and quantitative genetic characteristics of salmon in the system. Results We show that at least 20 microsatellites (ave. 12 alleles/locus) are required to maximise parentage assignment and to improve the power to estimate reproductive success and heritability in this study system. We also show that 1.5 fold differences can be detected between groups simulated to have differing reproductive success, and that it is possible to detect moderate heritability values for continuous traits (h2 ~ 0.40) with more than 80% power when using 28 moderately to highly polymorphic markers. Conclusion The methodologies and work flow described provide a robust approach for evaluating archived samples for pedigree-based research, even where only a proportion of the total population is sampled. The

  16. The Unbearable Lightness of PIN Cracking

    NASA Astrophysics Data System (ADS)

    Berkman, Omer; Ostrovsky, Odelia Moshe

    We describe new attacks on the financial PIN processing API. The attacks apply to switches as well as to verification facilities. The attacks are extremely severe allowing an attacker to expose customer PINs by executing only one or two API calls per exposed PIN. One of the attacks uses only the translate function which is a required function in every switch. The other attacks abuse functions that are used to allow customers to select their PINs online. Some of the attacks can be applied in switches even though the attacked functions require issuer's keys which do not exist in a switch. This is particularly disturbing as it was widely believed that functions requiring issuer's keys cannot do any harm if the respective keys are unavailable.

  17. The actuated latch pin and its development

    NASA Technical Reports Server (NTRS)

    Lawlor, P. J.

    1980-01-01

    An actuated latch pin developed to meet the need for a reusable locking device is described. The unit can function as a pin puller or as a pin pusher latch. Initial prototype testing demonstrated the feasibility of the device with the unit being driven from a 28 V dc supply and using 15 W to drive a 12 mm diameter pin through a stroke of 10 mm with a side load of 100 N in 120 ms. High wear rates with a MOS2 lubrication on the ballscrew and angular contact bearings have necessitated the reduction in the duty cycle from 1000 cycles in air and vacuum to 100 in air and 1000 in vacuum.

  18. Quick-Release Pin With Lever Action

    NASA Technical Reports Server (NTRS)

    Trevino, Robert C.

    1995-01-01

    Lever-action quick-release pin operated more easily. Mechanism operated with gloved hand. In modified version, lever added to handle to facilitate actuation. Lever action reduces actuation force. Lever-action pin operated by squeezing on any point of moveable ends of lever and handle together between thumb and forefinger or by simply grasping and squeezing handle and lever with entire hand in more natural grasp.

  19. IMp: The customizable LEGO® Pinned Insect Manipulator

    PubMed Central

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    Abstract We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble. PMID:25685035

  20. Performance measurements of hybrid PIN diode arrays

    SciTech Connect

    Shapiro, S.L. ); Arens, J.F.; Jernigan, J.G. . Space Sciences Lab.); Kramer, G. ); Collins, T.; Worley, S. ); Wilburn, C.D. ); Skubic, P. )

    1990-10-01

    We report the successful development of hybrid PIN diode arrays and a series of room-temperature measurements in a high-energy pion beam at FNAL. A PMOS VLSI 256 {times} 256 readout array having 30 {mu}m square pixels was indium-bump bonded to a mating PIN diode detector array. Preliminary measurements on the resulting hybrid show excellent signal-to-noise at room temperature. 3 refs., 5 figs.

  1. Investigating Dynamic Interdomain Allostery in Pin1

    PubMed Central

    Peng, Jeffrey W.

    2015-01-01

    Signaling proteins often sequester complementary functional sites in separate domains. How do the different domains communicate with one another? An attractive system to address this question is the mitotic regulator, human Pin1 (Lu et al. 1996). Pin-1 consists of two tethered domains: a WW domain for substrate binding, and a catalytic domain for peptidyl-prolyl isomerase (PPIase) activity. Pin1 accelerates the cis-trans isomerization of phospho-Ser/Thr-Pro (pS/T-P) motifs within proteins regulating the cell cycle and neuronal development. The early x-ray (Ranganathan et al. 1997; Verdecia et al. 2000) and solution NMR studies (Bayer et al. 2003; Jacobs et al. 2003) of Pin1 indicated inter- and intradomain motion. We became interested in exploring how such motions might affect interdomain communication, using NMR. Our accumulated results indicate substrate binding to Pin1 WW domain changes the intra/inter domain mobility, thereby altering substrate activity in the distal PPIase domain catalytic site. Thus, Pin1 shows evidence of dynamic allostery, in the sense of Cooper and Dryden (Cooper and Dryden 1984). We highlight our results supporting this conclusion, and summarize them via a simple speculative model of conformational selection. PMID:26495045

  2. Reconstruction of the Radiation Emergency Medical System From the Acute to the Sub-acute Phases After the Fukushima Nuclear Power Plant Crisis

    PubMed Central

    OJINO, Mayo; ISHII, Masami

    2014-01-01

    The radiation emergency medical system in Japan ceased to function as a result of the accident at the Fukushima Daiichi Nuclear Power Plant, which has commonly become known as the “Fukushima Accident.” In this paper, we review the reconstruction processes of the radiation emergency medical system in order of events and examine the ongoing challenges to overcoming deficiencies and reinforcing the system by reviewing relevant literature, including the official documents of the investigation committees of the National Diet of Japan, the Japanese government, and the Tokyo Electric Power Company, as well as technical papers written by the doctors involved in radiation emergency medical activities in Fukushima. Our review has revealed that the reconstruction was achieved in 6 stages from March 11 to July 1, 2011: (1) Re-establishment of an off-site center (March 13), (2) Re-establishment of a secondary radiation emergency hospital (March 14), (3) Reconstruction of the initial response system for radiation emergency care (April 2), (4) Reinforcement of the off-site center and stationing of disaster medical advisors at the off-site center (April 4), (5) Reinforcement of the medical care system and an increase in the number of hospitals for non-contaminated patients (From April 2 to June 23), and (6) Enhancement of the medical care system in the Fukushima Nuclear Power Plant and the construction of a new medical care system, involving both industrial medicine and emergency medicine (July 1). Medical resources such as voluntary efforts, academic societies, a local community medical system and university hospitals involved in medical care activities on 6 stages originally had not planned. In the future, radiation emergency medical systems should be evaluated with these 6 stages as a basis, in order to reinforce and enrich both the existing and backup systems so that minimal harm will come to nuclear power plant workers or evacuees and that they will receive proper care

  3. Self-locking double retention redundant pull pin release

    NASA Technical Reports Server (NTRS)

    Killgrove, Thomas O. (Inventor)

    1987-01-01

    A double-retention redundant pull pin release system is disclosed. The system responds to a single pull during an intentional release operation. A spiral-threaded main pin is seated in a mating bore in a housing, which main pin has a flange fastened thereon at the part of the main pin which is exterior to the housing. Accidental release tends to rotate the main pin. A secondary pin passes through a slightly oversized opening in the flange and is seated in a second bore in the housing. The pins counteract against one another to prevent accidental release. A frictional lock is shared between the main and secondary pins to enhance further locking of the system. The secondary pin, in response to a first pull, is fully retracted from its bore and flange hole. Thereafter the pull causes the main pin to rotate free of the housing to release, for example, a parachute mechanism.

  4. Temperature Distributions in LMR Fuel Pin Bundles as Modeled by COBRA-IV-I

    NASA Astrophysics Data System (ADS)

    Wright, Steven A.; Stout, Sherry

    2005-02-01

    Most pin type reactor designs for space power or terrestrial applications group the fuel pins into a number of relatively large fuel pin bundles or subassemblies. Fuel bundles for terrestrial liquid metal fast breeders reactors typically use 217 - 271 pins per sub-assembly, while some SP100 designs use up to 331 pins in a central subassembly that was surrounded by partial assemblies. Because thermal creep is exponentially related to temperature, small changes in fuel pin cladding temperature can make large differences in the lifetime in a high temperature liquid metal reactor (LMR). This paper uses the COBRA-IV-I computer code to determine the temperature distribution within LMR fuel bundles. COBRA-IV-I uses the sub-channel analysis approach to determine the enthalpy (or temperature) and flow distribution in rod bundles for both steady-state and transient conditions. The COBRA code runs in only a few seconds and has been benchmarked and tested extensively over a wide range of flow conditions. In this report the flow and temperature distributions for two types of lithium cooled space reactor core designs were calculated. One design uses a very tight fuel pin packing that has a pitch to diameter ratio of 1.05 (small wire wrap with a diameter of 392 μm) as proposed in SP100. The other design uses a larger pitch to diameter ratio of 1.09 with a larger more conventional sized wire wrap diameter of 1 mm. The results of the COBRA pin bundle calculations show that the larger pitch-to-diameter fuel bundle designs are more tolerant to local flow blockages, and in addition they are less sensitive to mal-flow distributions that occur near the edges of the subassembly.

  5. Temperature Distributions in LMR Fuel Pin Bundles as Modeled by COBRA-IV-I

    SciTech Connect

    Wright, Steven A.; Stout, Sherry

    2005-02-06

    Most pin type reactor designs for space power or terrestrial applications group the fuel pins into a number of relatively large fuel pin bundles or subassemblies. Fuel bundles for terrestrial liquid metal fast breeders reactors typically use 217 - 271 pins per sub-assembly, while some SP100 designs use up to 331 pins in a central subassembly that was surrounded by partial assemblies. Because thermal creep is exponentially related to temperature, small changes in fuel pin cladding temperature can make large differences in the lifetime in a high temperature liquid metal reactor (LMR). This paper uses the COBRA-IV-I computer code to determine the temperature distribution within LMR fuel bundles. COBRA-IV-I uses the sub-channel analysis approach to determine the enthalpy (or temperature) and flow distribution in rod bundles for both steady-state and transient conditions. The COBRA code runs in only a few seconds and has been benchmarked and tested extensively over a wide range of flow conditions. In this report the flow and temperature distributions for two types of lithium cooled space reactor core designs were calculated. One design uses a very tight fuel pin packing that has a pitch to diameter ratio of 1.05 (small wire wrap with a diameter of 392 {mu}m) as proposed in SP100. The other design uses a larger pitch to diameter ratio of 1.09 with a larger more conventional sized wire wrap diameter of 1 mm. The results of the COBRA pin bundle calculations show that the larger pitch-to-diameter fuel bundle designs are more tolerant to local flow blockages, and in addition they are less sensitive to mal-flow distributions that occur near the edges of the subassembly.

  6. Passive Time Coincidence Measurements with HEU Oxide Fuel Pins

    SciTech Connect

    McConchie, Seth M; Hausladen, Paul; Mihalczo, John T

    2008-01-01

    Passive time coincidence measurements have been performed on highly enriched uranium (HEU) oxide fuel pins at the Idaho National Laboratory Power Burst Facility. These experiments evaluate HEU detection capability using passive coincidence counting when utilizing moderated 3He tubes. Data acquisition was performed with the Nuclear Material Identification System (NMIS) to calculate the neutron coincidence time distributions. The amounts of HEU measured were 1 kg, 4 kg, and 8 kg in sealed 55-gallon drums. Data collected with the 3He tubes also include passive measurement of 31 kg of depleted uranium (DU) in order to determine the ability to distinguish HEU from DU. This paper presents results from the measurements.

  7. The influence of the repetition rate on the nanosecond pulsed pin-to-pin microdischarges

    NASA Astrophysics Data System (ADS)

    Huang, Bang-Dou; Takashima, Keisuke; Zhu, Xi-Ming; Pu, Yi-Kang

    2014-10-01

    The effect of repetition rate on a nanosecond atmospheric pressure discharge is investigated. The discharge is generated between two pins in a mixture of Ne and Ar. The voltage, current, power waveforms and the temporally and spatially resolved electron density and an ‘effective’ electron temperature are measured, with a pulse interval between 1.5 and 200 µs. It is found that not only does the repetition rate have a strong influence on the breakdown voltage and the peak discharge power, but it can also affect the rise rate of the volume averaged electron density and its peak value. Temporally and spatially resolved measurement of the electron density and the effective electron temperature show that the spatial distributions of both quantities are also influenced by the repetition rate. In the initial discharge period of all cases, the sharp rise of the electron density correlates with the drastic drop of the effective electron temperature. It is suggested that the residual charges have a strong impact on the axial distribution of the electric field and energetic electrons between the electrodes during the breakdown period, as illustrated by a simple sheath model.

  8. Temperature dependent simulation of diamond depleted Schottky PIN diodes

    NASA Astrophysics Data System (ADS)

    Hathwar, Raghuraj; Dutta, Maitreya; Koeck, Franz A. M.; Nemanich, Robert J.; Chowdhury, Srabanti; Goodnick, Stephen M.

    2016-06-01

    Diamond is considered as an ideal material for high field and high power devices due to its high breakdown field, high lightly doped carrier mobility, and high thermal conductivity. The modeling and simulation of diamond devices are therefore important to predict the performances of diamond based devices. In this context, we use Silvaco® Atlas, a drift-diffusion based commercial software, to model diamond based power devices. The models used in Atlas were modified to account for both variable range and nearest neighbor hopping transport in the impurity bands associated with high activation energies for boron doped and phosphorus doped diamond. The models were fit to experimentally reported resistivity data over a wide range of doping concentrations and temperatures. We compare to recent data on depleted diamond Schottky PIN diodes demonstrating low turn-on voltages and high reverse breakdown voltages, which could be useful for high power rectifying applications due to the low turn-on voltage enabling high forward current densities. Three dimensional simulations of the depleted Schottky PIN diamond devices were performed and the results are verified with experimental data at different operating temperatures

  9. Whole-Pin Furnace system: An experimental facility for studying irradiated fuel pin behavior under potential reactor accident conditions

    SciTech Connect

    Liu, Y.Y.; Tsai, H.C.; Donahue, D.A.; Pushis, D.O.; Savoie, F.E.; Holland, J.W.; Wright, A.E.; August, C.; Bailey, J.L.; Patterson, D.R.

    1990-05-01

    The whole-pin furnace system is a new in-cell experimental facility constructed to investigate how irradiated fuel pins may fail under potential reactor accident conditions. Extensive checkouts have demonstrated excellent performance in remote operation, temperature control, pin breach detection, and fission gas handling. The system is currently being used in testing of EBIR-II-irradiated Integral Fast Reactor (IFR) metal fuel pins; future testing will include EBR-II-irradiated mixed-oxide fuel pins. 7 refs., 4 figs.

  10. The Maize PIN Gene Family of Auxin Transporters.

    PubMed

    Forestan, Cristian; Farinati, Silvia; Varotto, Serena

    2012-01-01

    Auxin is a key regulator of plant development and its differential distribution in plant tissues, established by a polar cell to cell transport, can trigger a wide range of developmental processes. A few members of the two families of auxin efflux transport proteins, PIN-formed (PIN) and P-glycoprotein (ABCB/PGP), have so far been characterized in maize. Nine new Zea mays auxin efflux carriers PIN family members and two maize PIN-like genes have now been identified. Four members of PIN1 (named ZmPIN1a-d) cluster, one gene homologous to AtPIN2 (ZmPIN2), three orthologs of PIN5 (ZmPIN5a-c), one gene paired with AtPIN8 (ZmPIN8), and three monocot-specific PINs (ZmPIN9, ZmPIN10a, and ZmPIN10b) were cloned and the phylogenetic relationships between early-land plants, monocots, and eudicots PIN proteins investigated, including the new maize PIN proteins. Tissue-specific expression patterns of the 12 maize PIN genes, 2 PIN-like genes and ZmABCB1, an ABCB auxin efflux carrier, were analyzed together with protein localization and auxin accumulation patterns in normal conditions and in response to drug applications. ZmPIN gene transcripts have overlapping expression domains in the root apex, during male and female inflorescence differentiation and kernel development. However, some PIN family members have specific tissue localization: ZmPIN1d transcript marks the L1 layer of the shoot apical meristem and inflorescence meristem during the flowering transition and the monocot-specific ZmPIN9 is expressed in the root endodermis and pericycle. The phylogenetic and gene structure analyses together with the expression pattern of the ZmPIN gene family indicate that subfunctionalization of some maize PINs can be associated to the differentiation and development of monocot-specific organs and tissues and might have occurred after the divergence between dicots and monocots. PMID:22639639

  11. Ratchet effect in a conformal pinning array

    NASA Astrophysics Data System (ADS)

    Janko, Boldizsar; Ray, Dipanjan; Olson Reichhardt, Cynthia; Reichhardt, Charles

    2014-03-01

    Pinning arrays where the pinning sites are located at the vertices of a conformally transformed hexagonal lattice, also known as conformal pinning arrays (CPA), have recently been shown to greatly enhance the critical current of type-II superconductors both in simulation and in experiment. Here we show using molecular dynamics simulations that the differing flux-flow resistance of the CPA in the forward and reverse directions causes it to function as a highly effective vortex ratchet. We drive the vortices using an applied external ac current, and we find that the resulting dc output voltage for the CPA ratchet is larger than that for a random pinning array with a pinning gradient by up to an order of magnitude. The enhancement is robust over a wide range of vortex densities, temperatures, and ac drive amplitudes and frequencies. D. Ray et al, Phys. Rev. Lett. 110, 267001 (2013); Y. L. Wang et al, Phys. Rev. B 87, 220501(R) (2013); S. Guenon et al, Appl. Phys. Lett. 102, 252602 (2013).

  12. Statistics of dislocation pinning at localized obstacles

    NASA Astrophysics Data System (ADS)

    Dutta, A.; Bhattacharya, M.; Barat, P.

    2014-10-01

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  13. Statistics of dislocation pinning at localized obstacles

    SciTech Connect

    Dutta, A.; Bhattacharya, M. Barat, P.

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  14. The Experimental Study of Atmospheric Stirling Engines Using Pin-Fin Arrays' Heat Exchangers

    NASA Astrophysics Data System (ADS)

    Isshiki, Seita; Sato, Hidekazu; Konno, Shoji; Shiraishi, Hiroaki; Isshiki, Naotsugu; Fujii, Iwane; Mizui, Hiroyuki

    This paper reports experimental results on two kinds of atmospheric Stirling engines that were designed and manufactured using a pin-fin array heat exchanger for the heater and cooler (abbreviated to “pin-fin Stirling engine” hereafter). The first one is a large β type pin-fin Stirling engine with a 1.7-liter displacement volume and power piston volume. The heater consists of an aluminum circular disk with a diameter of 270mm and with large-scale pin-fin arrays carved into the surface. The maximum output reached 91W at a temperature difference of 330K, which is 36% of the scheduled value and 68% of the Kolin's cubic power law. The maximum thermal efficiency was estimated 4.2%. The second engine is an α type pin-fin Stirling engine. Glass syringes were used for the piston-cylinder system and the Ross-yoke mechanism was used for the crank mechanism. By changing temperature difference, the characteristic of output torque in the large range was measured with a precision torque detector.

  15. A division in PIN-medicated patterning during lateral organ initiation in grasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using phlyogenic and gene synteny analysis we identified an angiosperm PIN clade sister to PIN1, here termed SISter-of-PIN1 (soPIN1), which is present in all sampled angiosperms except for Brassicaceae. Additionally, we identified a conserved duplication of PIN1 in the grasses: PIN1a and PIN1b. In...

  16. Transportation of pinned charge density waves

    NASA Astrophysics Data System (ADS)

    Koo, Je Huan; Jeong, Jae Yoon; Cho, Guangsup

    2009-01-01

    We investigated the transport of pinned charge density waves (CDWs) that is observed in low dimensional materials. We treated pinned CDWs as moving CDWs that were confined within a typical quantum well amongst the many different types where pinning occurs at the barrier. We calculated the current flowing out of the quantum well by confined CDWs. The calculated conductivity is in good correspondence with experimental data in TTF-TCNQ, where the measured Fröhlich-Peierls temperature is 60 K much higher than the theoretical value of 20 K. The voltage dependence of the conductivity was calculated, where this is easily transformed into the dependence of electric field. The magnetic susceptibility was also calculated with a similar trend of experimental data. The susceptibility is a diamagnetic contribution by CDWs in addition to the constant background Pauli paramagnetic part.

  17. PINS Testing and Modification for Explosive Identification

    SciTech Connect

    E.H. Seabury; A.J. Caffrey

    2011-09-01

    The INL's Portable Isotopic Neutron Spectroscopy System (PINS)1 non-intrusively identifies the chemical fill of munitions and sealed containers. PINS is used routinely by the U.S. Army, the Defense Threat Reduction Agency, and foreign military units to determine the contents of munitions and other containers suspected to contain explosives, smoke-generating chemicals, and chemical warfare agents such as mustard and nerve gas. The objects assayed with PINS range from softball-sized M139 chemical bomblets to 200 gallon DOT 500X ton containers. INL had previously examined2 the feasibility of using a similar system for the identification of explosives, and based on this proof-of-principle test, the development of a dedicated system for the identification of explosives in an improvised nuclear device appears entirely feasible. INL has been tasked by NNSA NA-42 Render Safe Research and Development with the development of such a system.

  18. Flows in Pinned Arrays Simulating Brush Seals

    NASA Technical Reports Server (NTRS)

    Hendricks, R.C.; Kudriavtsev, V. V.; Braun, M. J.; Athavale, M. M.

    1996-01-01

    Flows through idealized pin arrays were investigated using an unstructured grid finite difference model and the simplified Ergun model to predict leakage flows and pressure drops in brush seals. The models are in good agreement in the laminar region with departures in the laminar-turbulent transition region defined by the simplified Ergun model. No local disturbances in the velocity or pressure fields, symptomatic of turbulence were found in the numerical results. The simplified model failed to predict the pressure drop of a 32-pin anisotropic array. Transitional and anisotropic behavior requires

  19. Penile Reconstruction

    PubMed Central

    Salgado, Christopher J.; Chim, Harvey; Tang, Jennifer C.; Monstrey, Stan J.; Mardini, Samir

    2011-01-01

    A variety of surgical options exists for penile reconstruction. The key to success of therapy is holistic management of the patient, with attention to the psychological aspects of treatment. In this article, we review reconstructive modalities for various types of penile defects inclusive of partial and total defects as well as the buried penis, and also describe recent basic science advances, which may promise new options for penile reconstruction. PMID:22851914

  20. RigidFix femoral fixation: a test for detecting inaccurate cross pin positioning.

    PubMed

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Dimitriadis, Theofilos; Pappis, Georgios; Parisis, Constantinos A

    2007-11-01

    The RigidFix Cross Pin System (DePuy Mitek, Raynham, MA) is a popular technique for femoral fixation of graft in ACL reconstruction. In some cases, though, cross pins miss the femoral tunnel resulting in inadequate proximal graft fixation. We present a simple test to detect the incorrect placement of cross pins. The pinholes are drilled through the guide frame, leaving 2 sleeves for cross pins insertion. The manufacturer's recommendations, at this stage, are to reinsert the femoral tunnel guidewire, remove the guide frame, and insert the graft without verifying accurate pinhole positioning. We reinsert the femoral tunnel guidewire without removing the guide frame, and a second guidewire is introduced through each of the sleeves in turn. In case of appropriate pinhole placement, the 2 guidewires will meet in the cannulated rod of the guide frame and the surgeon will have the metal-to-metal feeling. If the pinhole misses the femoral tunnel, the 2 guidewires will not meet and the surgeon will not have the metal-to-metal feeling. In our practice, 9 cases of inaccurate pinhole placement were detected with this test and verified by direct vision of the femoral tunnel with the arthroscope. We find this test simple, reliable, and not time consuming. PMID:17986419

  1. Fabrication of 3-μm diameter pin hole array (PHA) on thick W substrates

    NASA Astrophysics Data System (ADS)

    Levato, T.; Pathak, N. C.; Cecchetti, C. A.; Ciricosta, O.; Koester, P.; Labate, L.; Giulietti, A.; Giulietti, D.; De Angelis, F.; Di Fabrizio, E.; Delogu, P.; Gizzi, L. A.

    2010-02-01

    Pin-hole arrays are used for a variety of applications including, for example, X-ray imaging of laser-plasmas for fusion relevant studies [1]. More recently, a novel X-ray imaging technique has been proposed (this conference L. A. Gizzi et al.) within the High Power Laser Energy Research Facility (HiPER) to obtain spectrally resolved X-ray imaging [2] using single photon detection [3]. This technique requires a large number of images or, alternatively, large arrays of pin-holes, possibly with very small diameter («10 μm) [4]. In view of this, a technique was implemented for the fabrication of large arrays of pin-holes in thick metal substrates. Here we report on the optimizations of the laser-matter interaction process to obtain high aspect ratio cylinder-like pin-hole on heavy metal substrate by using a frequency-doubled Ti:Sa femtosecond laser pulses operating at 10 Hz. The influence of an air breakdown and a (ns)prepulse, on the drilled pin-hole, is showed by means of SEM images both for surface effects and internal quality of the channels, with evidence of micro and nano-sized structures. The holes drilled at an intensity just below the laser breakdown threshold for plasma creation in air, have an internal diameter of about 3 μm on a W substrate of 70 μm thickness, a micro-cylinder-like shape and no detectable deviations of the axis from a straight line. Arrays of up to 800 pin-holes were produced with the pin-hole properties being highly stable across the array. The final X-ray transmission is showed by using a μ-focus X-ray source.

  2. Fabrication of 3-{mu}m diameter pin hole array (PHA) on thick W substrates

    SciTech Connect

    Levato, T.; Pathak, N. C.; Ciricosta, O.; Cecchetti, C. A.; Koester, P.; Labate, L.; Giulietti, A.; Gizzi, L. A.; Giulietti, D.; De Angelis, F.; Di Fabrizio, E.; Delogu, P.

    2010-02-02

    Pin-hole arrays are used for a variety of applications including, for example, X-ray imaging of laser-plasmas for fusion relevant studies. More recently, a novel X-ray imaging technique has been proposed (this conference L. A. Gizzi et al.) within the High Power Laser Energy Research Facility (HiPER) to obtain spectrally resolved X-ray imaging using single photon detection. This technique requires a large number of images or, alternatively, large arrays of pin-holes, possibly with very small diameter (<<10 {mu}m). In view of this, a technique was implemented for the fabrication of large arrays of pin-holes in thick metal substrates. Here we report on the optimizations of the laser-matter interaction process to obtain high aspect ratio cylinder-like pin-hole on heavy metal substrate by using a frequency-doubled Ti:Sa femtosecond laser pulses operating at 10 Hz. The influence of an air breakdown and a (ns)prepulse, on the drilled pin-hole, is showed by means of SEM images both for surface effects and internal quality of the channels, with evidence of micro and nano-sized structures. The holes drilled at an intensity just below the laser breakdown threshold for plasma creation in air, have an internal diameter of about 3 {mu}m on a W substrate of 70 {mu}m thickness, a micro-cylinder-like shape and no detectable deviations of the axis from a straight line. Arrays of up to 800 pin-holes were produced with the pin-hole properties being highly stable across the array. The final X-ray transmission is showed by using a mu-focus X-ray source.

  3. Rotary pin-in-maze discriminator

    DOEpatents

    Benavides, Gilbert L.

    1997-01-01

    A discriminator apparatus and method that discriminates between a unique signal and any other (incorrect) signal. The unique signal is a sequence of events; each event can assume one of two possible event states. Given the unique signal, a maze wheel is allowed to rotate fully in one direction. Given an incorrect signal, both the maze wheel and a pin wheel lock in position.

  4. 49 CFR 230.97 - Crank pins.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Crank pins. 230.97 Section 230.97 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Driving...

  5. Valve for fuel pin loading system

    DOEpatents

    Christiansen, David W.

    1985-01-01

    A cyclone valve surrounds a wall opening through which cladding is projected. An axial valve inlet surrounds the cladding. Air is drawn through the inlet by a cyclone stream within the valve. An inflatable seal is included to physically engage a fuel pin subassembly during loading of fuel pellets.

  6. Mesoscopic pinning forces in neutron star crusts

    NASA Astrophysics Data System (ADS)

    Seveso, S.; Pizzochero, P. M.; Grill, F.; Haskell, B.

    2016-02-01

    The crust of a neutron star is thought to be comprised of a lattice of nuclei immersed in a sea of free electrons and neutrons. As the neutrons are superfluid, their angular momentum is carried by an array of quantized vortices. These vortices can pin to the nuclear lattice and prevent the neutron superfluid from spinning down, allowing it to store angular momentum which can then be released catastrophically, giving rise to a pulsar glitch. A crucial ingredient for this model is the maximum pinning force that the lattice can exert on the vortices, as this allows us to estimate the angular momentum that can be exchanged during a glitch. In this paper, we perform, for the first time, a detailed and quantitative calculation of the pinning force per unit length acting on a vortex immersed in the crust and resulting from the mesoscopic vortex-lattice interaction. We consider realistic vortex tensions, allow for displacement of the nuclei and average over all possible orientations of the crystal with respect to the vortex. We find that, as expected, the mesoscopic pinning force becomes weaker for longer vortices and is generally much smaller than previous estimates, based on vortices aligned with the crystal. Nevertheless, the forces we obtain still have maximum values of the order of fpin ≈ 1015 dyn cm-1, which would still allow for enough angular momentum to be stored in the crust to explain large Vela glitches, if part of the star is decoupled during the event.

  7. Flux pinning and stabilizer studies. Final report

    SciTech Connect

    Collings, E.W.

    1994-11-29

    A synopsis of the results of the flux-pinning and stabilizer studies that form the central theme of the subject contract is followed by a list of papers that were published during the period August 28, 1986 to November 31, 1992.

  8. Valve for fuel pin loading system

    DOEpatents

    Christiansen, D.W.

    1984-01-01

    A cyclone valve surrounds a wall opening through which cladding is projected. An axial valve inlet surrounds the cladding. Air is drawn through the inlet by a cyclone stream within the valve. An inflatable seal is included to physically engage a fuel pin subassembly during loading of fuel pellets.

  9. 8. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR BEAM, STRINGERS, LATTICE BRACING, EYEBARS, AND PIN, LOOKING SOUTH - Four Mile Bridge, Spanning Elk River on County Road 42, Steamboat Springs, Routt County, CO

  10. Vortex creep and thermal depinning within strong pinning theory

    NASA Astrophysics Data System (ADS)

    Willa, Roland; Buchacek, Martin; Geshkenbein, Vadim B.; Blatter, Gianni

    Vortex pinning in type-II superconductors can occur through the collective action of many pins (weak collective pinning scenario) or through plastic deformations induced by a low density of defects (strong pinning scenario). For the latter case, a new formalism has recently be developed to provide a quantitative link between the microscopic pinning landscape and experimentally accessible quantities describing pinning on a macroscopic level. Examples are the critical current density jc, the I- V characteristics, or the ac Campbell length λC. Inspired by the original work of Larkin and Brazovskii on density wave pinning, we have extended the strong pinning formalism to account for thermal depinning of flux lines and vortex creep.

  11. Penile reconstruction

    PubMed Central

    Garaffa, Giulio; Sansalone, Salvatore; Ralph, David J

    2013-01-01

    During the most recent years, a variety of new techniques of penile reconstruction have been described in the literature. This paper focuses on the most recent advances in male genital reconstruction after trauma, excision of benign and malignant disease, in gender reassignment surgery and aphallia with emphasis on surgical technique, cosmetic and functional outcome. PMID:22426595

  12. Image reconstruction

    SciTech Connect

    Defrise, Michel; Gullberg, Grant T.

    2006-04-05

    We give an overview of the role of Physics in Medicine andBiology in development of tomographic reconstruction algorithms. We focuson imaging modalities involving ionizing radiation, CT, PET and SPECT,and cover a wide spectrum of reconstruction problems, starting withclassical 2D tomogra tomography in the 1970s up to 4D and 5D problemsinvolving dynamic imaging of moving organs.

  13. Reconstructing the Chernobyl Nuclear Power Plant (CNPP) accident 30 years after. A unique database of air concentration and deposition measurements over Europe.

    PubMed

    Evangeliou, Nikolaos; Hamburger, Thomas; Talerko, Nikolai; Zibtsev, Sergey; Bondar, Yuri; Stohl, Andreas; Balkanski, Yves; Mousseau, Timothy A; Møller, Anders P

    2016-09-01

    30 years after the Chernobyl Nuclear Power Plant (CNPP) accident, its radioactive releases still remain of great interest mainly due to the long half-lives of many radionuclides emitted. Observations from the terrestrial environment, which hosts radionuclides for many years after initial deposition, are important for health and environmental assessments. Furthermore, such measurements are the basis for validation of atmospheric transport models and can be used for constraining the still not accurately known source terms. However, although the "Atlas of cesium deposition on Europe after the Chernobyl accident" (hereafter referred to as "Atlas") has been published since 1998, less than 1% of the direct observations of (137)Cs deposition has been made publicly available. The remaining ones are neither accessible nor traceable to specific data providers and a large fraction of these data might have been lost entirely. The present paper is an effort to rescue some of the data collected over the years following the CNPP accident and make them publicly available. The database includes surface air activity concentrations and deposition observations for (131)I, (134)Cs and (137)Cs measured and provided by Former Soviet Union authorities the years that followed the accident. Using the same interpolation tool as the official authorities, we have reconstructed a deposition map of (137)Cs based on about 3% of the data used to create the Atlas map. The reconstructed deposition map is very similar to the official one, but it has the advantage that it is based exclusively on documented data sources, which are all made available within this publication. In contrast to the official map, our deposition map is therefore reproducible and all underlying data can be used also for other purposes. The efficacy of the database was proved using simulated activity concentrations and deposition of (137)Cs from a Langrangian and a Euleurian transport model. PMID:27376994

  14. Timing analysis of PWR fuel pin failures

    SciTech Connect

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. ); Straka, M. )

    1992-09-01

    This report discusses research conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PF1/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design burnup. Using peaking factors commensurate with actual burnups would result in longer intervals for both reactor designs. This document provides appendices K and L of this report which provide plots for the timing analysis of PWR fuel pin failures for Oconee and Seabrook respectively.

  15. Consolidated fuel reprocessing program: Criticality experiments with fast test reactor fuel pins in an organic moderator

    SciTech Connect

    Bierman, S.R.

    1986-12-01

    The results obtained in a series of criticality experiments performed as part of a joint program on criticality data development between the United States Department of Energy and the Power Reactor and Nuclear Fuel Development Corporation of Japan are presented in this report along with a complete description of the experiments. The experiments involved lattices of Fast Test Reactor (FTR) fuel pins in an organic moderator mixture similar to that used in the solvent extraction stage of fuel reprocessing. The experiments are designed to provide data for direct comparison with previously performed experimental measurements with water moderated lattices of FTR fuel pins. The same lattice arrangements and FTR fuel pin types are used in these organic moderated experimental assemblies as were used in the water moderated experiments. The organic moderator is a mixture of 38 wt % tributylphosphate in a normal paraffin hydrocarbon mixture of C{sub 11}H{sub 24} to C{sub 15}H{sub 32} molecules. Critical sizes of 1054.8, 599.2, 301.8, 199.5 and 165.3 fuel pins were obtained respectively for organic moderated lattices having 0.761 cm, 0.968 cm, 1.242 cm, 1.537 cm and 1.935 cm square lattice pitches as compared to 1046.9, 571.9, 293.9, 199.7 and 165.1 fuel pins for the same lattices water moderated.

  16. Effect of magnetic element ions on collective pinning behaviour in Bi-2223 quadrilateral bars

    NASA Astrophysics Data System (ADS)

    Adam, M. I.

    2007-10-01

    Frequency and ac field dependence of Bi1.6Pb0.4Sr2(Ca1-xMx)2Cu3Oδ quadrilateral bars with x ⩽ 0.02 and M = Pr, Nd, Sm, Gd and Ni, prepared by the conventional reaction method have been measured in the range of low field/frequency ac susceptibility and BSCCO superconducting temperature. The ac loss peak shifts to higher temperature and its summit shows nonlinear change with increasing frequency. Introduction of magnetic ions as defects is found to increase the intergranular critical current Jcm and the flux pinning of Bi(Pb)-2223 system. Application of the power law critical state model suggested that pinning behaviour of specimen could be viewed as hysteretic bulk pinning and/or flux creep. On the other hand, Jcm dependence activation energy is found to obey Ea ∝ J-μ relation, characteristic of the vortex glass/collective creep. Hence, collective pinning behaviour of specimens is discussed in view of the intergranular pinning mechanism.

  17. Anisotropic flux pinning energy in FeSexTe1-x single crystals

    NASA Astrophysics Data System (ADS)

    Wu, Zhaofeng; Tao, Jian; Xu, Xibin; Qiu, Li; Yang, Shaoguang; Wang, Zhihe

    2016-09-01

    FeSexTe1 - x (x = 0.3, 0.4, 0.5, 0.6, 0.7) single crystals have been prepared by the chemical reaction of the elements. The field dependence of flux pinning energy shows a power law behavior, U∝H-α, where α displays a crossover at H ∼ 2 T from small value at low field to large value at high field for both magnetic fields perpendicular and parallel to c-axis. At same field, the flux pinning energy for H//ab-plane is higher than that for H//c-axis, showing an anisotropic behavior. The crossover maybe correspond to the flux pinning from single vortex pinning to collective pinning with magnetic field increasing. Based on the anisotropic G-L theory, the angular dependence of in-plane resistivity ρ in different magnetic fields at fixed temperature can be scaled by the equation, Hc2 GL (θ) =Hc2c /√{(cos2(θ) +γ-2sin2(θ)) } . The weak temperature dependence of anisotropic parameter γ near Tc was given for FeSe0.5Te0.5 and FeSe0.4Te0.6 crystals, respectively.

  18. Molecular Dynamic Simulation of Sodium in 7-Pin LMFBR Bundle Under Hypothetical Accident Conditions

    SciTech Connect

    Bottoni, Maurizio; Bottoni, Claudio; Scanu, John

    2006-07-01

    In the frame of safety analysis of liquid metal fast breeder reactors (LMFBRs) under hypothetical Unprotected Loss of Flow (ULOF) conditions two-phase flow of sodium is simulated in a 7-pin bundle, with hexagonal lattice. Molecular dynamics, with the application of the Direct Simulation Monte Carlo (DSMC) method, and a macroscopic model describing rewetting sequences due to the flow of a sodium liquid film along the pin surfaces, are applied to simulate the coolant in the bundle. The pin surfaces and the inner surface of the hexagonal canning are treated in the Monte Carlo simulation as diffusively reflecting surfaces. Collisions of sodium molecules are computed with the 'hard-sphere' model. With respect to previous work the following improvements of the computational code were made: i) The full bundle is simulated, thus allowing for asymmetries, like a skewed power distribution, to be accounted for; ii) A pin model calculates detailed temperature distributions in the pins, so that temperature boundary conditions are computed and not imposed; iii) Post processing visualisation of computed results was developed. An out of pile sodium boiling experiment run at the Nuclear Research Center of Karlsruhe, Germany, is simulated and conclusions are drawn about the applicability of the methodology in computer codes dedicated to breeder reactors safety analysis. (authors)

  19. Low-dark current 1024×1280 InGaAs PIN arrays

    NASA Astrophysics Data System (ADS)

    Yuan, Ping; Chang, James; Boisvert, Joseph C.; Karam, Nasser

    2014-06-01

    Photon counting imaging applications requires low noise from both detector and readout integrated circuit (ROIC) arrays. In order to retain the photon-counting-level sensitivity, a long integration time has to be employed and the dark current has to be minimized. It is well known that the PIN dark current is sensitive to temperature and a dark current density of 0.5 nA/cm2 was demonstrated at 7 °C previously. In order to restrain the size, weight, and power consumption (SWaP) of cameras for persistent large-area surveillance on small platforms, it is critical to develop large format PIN arrays with small pitch and low dark current density at higher operation temperatures. Recently Spectrolab has grown, fabricated and tested 1024x1280 InGaAs PIN arrays with 12.5 μm pitch and achieved 0.7 nA/cm2 dark current density at 15 °C. Based on our previous low-dark-current PIN designs, the improvements were focused on 1) the epitaxial material design and growth control; and 2) PIN device structure to minimize the perimeter leakage current and junction diffusion current. We will present characterization data and analyses that illustrate the contribution of various dark current mechanisms.

  20. Super-Junction PIN Photodiode to Integrate Optoelectronic Integrated Circuits in Standard Technologies: A Numerical Study

    NASA Astrophysics Data System (ADS)

    Roig, Jaume; Stefanov, Evgueniy; Morancho, Frédéric

    2007-07-01

    The use of super-junction (SJ) techniques in PIN photodiodes is proposed in this letter for the first time with the objective to assist the optoelectronic integrated circuits (OEICs) implementation in complementary metal oxide semiconductor (CMOS), bipolar CMOS (BiCMOS) and bipolar-CMOS-double diffused MOS (BCD) technologies. Its technological viability is also discussed to make it credible as an alternative to other OEICs approaches. Numerical simulation of realistic SJ-PIN devices, widely used in high power electronics, demonstrates the possibility to integrate high-performance CMOS-based OEICs in epitaxial layers with doping concentrations above 1× 1015 cm-3. The induced lateral depletion at low reverse biased voltage, assisted by the alternated N and P-doped pillars, allows high-speed transient response in SJ-PIN detecting wavelengths between 400 and 800 nm. Moreover, other important parameters as the responsivity and the dark current are not degraded in respect to the conventional PIN (C-PIN) structures.

  1. Effects of Pin Detached Space on Heat Transfer and Pin-Fin Arrays

    SciTech Connect

    Siw, Sin C.; Chyu, Minking K.; Shih, Tom I-P.; Alvin, Mary Anne

    2012-08-01

    Heat transfer and pressure characteristics in a rectangular channel with pin-fin arrays of partial detachment from one of the endwalls have been experimentally studied. The overall channel geometry (W = 76.2 mm, E = 25.4 mm) simulates an internal cooling passage of wide aspect ratio (3:1) in a gas turbine airfoil. With a given pin diameter, D = 6.35 mm = ¼E, three different pin-fin height-to-diameter ratios, H/D = 4, 3, and 2, were examined. Each of these three cases corresponds to a specific pin array geometry of detachment spacing (C) between the pin tip and one of the endwalls, i.e., C/D = 0, 1, 2, respectively. The Reynolds number, based on the hydraulic diameter of the unobstructed cross-section and the mean bulk velocity, ranges from 10,000 to 25,000. The experiment employs a hybrid technique based on transient liquid crystal imaging to obtain the distributions of the local heat transfer coefficient over all of the participating surfaces, including the endwalls and all the pin elements. Experimental results reveal that the presence of a detached space between the pin tip and the endwall has a significant effect on the convective heat transfer and pressure loss in the channel. The presence of pin-to-endwall spacing promotes wall-flow interaction, generates additional separated shear layers, and augments turbulent transport. In general, an increase in detached spacing, or C/D, leads to lower heat transfer enhancement and pressure drop. However, C/D = 1, i.e., H/D = 3, of a staggered array configuration exhibits the highest heat transfer enhancement, followed by the cases of C/D = 0 and C/D = 2, i.e., H/D = 4 or 2, respectively.

  2. Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization

    NASA Technical Reports Server (NTRS)

    Oelgoetz, Peter

    2000-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893.507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  3. Pin Load Control Applied to Retractable Pin Tool Technology and Its Characterization

    NASA Technical Reports Server (NTRS)

    Olegoetz, P.

    1999-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase IIA RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  4. Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization

    NASA Technical Reports Server (NTRS)

    Oelgoetz, Peter A.

    2000-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  5. A Biomechanical Comparison Of Pin Configurations Used For Percutaneous Pinning Of Distal Tibia Fractures In Children

    PubMed Central

    Brantley, Justin; Majumdar, Aditi; Jobe, J. Taylor; Kallur, Antony; Salas, Christina

    2016-01-01

    Background Percutaneous pin fixation is often used in conjunction with closed-reduction and cast immobilization to treat pediatric distal tibia fractures. The goal of this procedure is to maintain reduction and provide improved stabilization, in effort to facilitate a more anatomic union. We conducted a biomechanical study of the torsional and bending stability of three commonly used pin configurations in distal tibia fracture fixation. Methods A transverse fracture was simulated at the metaphyseal/diaphyseal junction in 15 synthetic tibias. Each fracture was reduced and fixed with two Kirschner wires, arranged in one of three pin configurations: parallel, retrograde, medial to lateral pins entering at the medial malleolus distal to the fracture (group A); parallel, antegrade, medial to lateral pins entering at the medial diaphysis proximal to the fracture (group B); or a cross-pin configuration with one retrograde, medial to lateral pin entering the medial malleolus distal to the fracture and the second an antegrade, medial to lateral pin entering at the medial diaphysis proximal to the fracture (group C). Stability of each construct was assessed by resistance to torsion and bending. Results Resistance to external rotation stress was significantly higher in group A than group B (P = 0.044). Resistance to internal rotation stress was significantly higher in group C than group B (P = 0.003). There was no significant difference in torsional stiffness when comparing group A with group C. Under a medial-directed load, group B and C specimens were significantly stiffer than those in group A (28 N/mm and 24 N/mm vs. 14 N/mm for A; P = 0.001 and P = 0.009, respectively) Conclusions None of the three pin configurations produced superior results with respect to all variables studied. Group A configuration provided the highest resistance to external rotation forces, which is the most clinically relevant variable under short-cast immobilization. Parallel, retrograde, medial

  6. Effects of three intramedullary pinning techniques on proximal pin location and articular damage in the canine tibia.

    PubMed

    Dixon, B C; Tomlinson, J L; Wagner-Mann, C C

    1994-01-01

    The effects of three different techniques of intramedullary (IM) pin placement on pin location and incidence of stifle joint injury were evaluated using 70 cadaver canine tibiae after mid-disphyseal osteotomy. In 50 tibiae, pins were placed retrograde in either a nondirected (group A) or a craniomedially directed fashion (group B) with 25 tibiae in each group. Pins were driven normograde (group N) in 20 tibiae. All the stifles were dissected to qualitatively evaluate pin interference with different joint structures. End-on radiographs of the tibial plateaus were used to quantitatively evaluate pin location. Interference with the caudal cruciate ligament, medial meniscus, lateral meniscus, or meniscal ligaments was not observed in any group. There was a significant association between pinning technique and incidence of involvement of the cranial cruciate ligament (P < .005), patella (P < .001), patellar ligament (P < .005), and femoral condyle (P < .01). Pin location for group A was significantly different from either other group in a cranial-caudal direction (P = .003), and was significantly different from group N in a medial-lateral direction (P = .005). No significant difference was observed between pin location for groups B and N in either plane. It was concluded that although nondirected retrograde pinning cannot be recommended, retrograde pins directed craniomedially may be an acceptable technique for the repair of proximal to mid-diaphyseal tibial fractures if care is taken to properly seat the pins. PMID:7871708

  7. Breast reconstruction.

    PubMed

    DellaCroce, Frank J; Wolfe, Emily T

    2013-04-01

    As diagnostic technology has progressed and the understanding of the disease process has evolved, the number of mastectomies performed in the United States has increased. Breast reconstructive techniques have commensurately become more sophisticated along the same timeline. The result is that those facing mastectomy have the potential to simultaneously retain physical beauty and wholeness. Only 33% of women who are otherwise candidates for immediate reconstruction at the time of mastectomy choose reconstruction. Patients generally have a high level of satisfaction with the option they choose, contributing to a feeling of overall recovery and physical and emotional wholeness. PMID:23464695

  8. Bending stiffness of conical and standard external fixator pins.

    PubMed

    Oni, O O; Capper, M; Soutis, C

    1993-10-01

    The bending stiffnesses of a conical and a standard external fixator pin have been compared. The pins were inserted into pilot holes in a piece of teak hardwood and loads of different magnitudes were applied at a fixed moment arm. Force-deflection curves were obtained for each pin, and stiffness (newtons per metre) and percentage stiffness reduction were calculated for each pilot hole size. The results show that deflection increased (i.e. stiffness decreased) with increasing force or diameter of pilot hole. This loss of stiffness was linear for the standard pin but was bimodal for the conical pin. PMID:8286671

  9. A comparative study of two types of sternal pins used for sternal closure: poly-L-lactide sternal pins versus uncalcined hydroxyapatite poly-L-lactide sternal pins.

    PubMed

    Fu, Xian-ming; Oshima, Hideki; Araki, Yoshimori; Narita, Yuji; Mutsuga, Masato; Okada, Noritaka; Tsunekawa, Tomohiro; Usui, Akihiko

    2013-12-01

    Bioabsorbable poly-L-lactide (PLLA) sternal pins are applied to reinforce sternal closure during cardiac surgery. However, these pins lack osteoconductivity. A new bioabsorbable sternal pin with osteoconductivity, made of uncalcined hydroxyapatite and poly-L-lactide (u-HA-PLLA) has been developed. This study was conducted to compare the two types of sternal pins in terms of sternal stability and healing after median sternotomy. Between October 2006 and January 2012, 105 patients underwent aortic surgery for aortic aneurysms or dissection via median sternotomy and sternal closure with sternal pins. Among these patients, 75 were followed for 12 months using serial computed tomography (CT). PLLA sternal pins were used in 30 patients (group A) and u-HA-PLLA sternal pins were used in 45 patients (group B). The incidence rates of transverse sternal dehiscence, anteroposterior displacement and complete sternal fusion were evaluated using CT. The cross-sectional cortical bone density area (CBDA) of the sternum around the sternal pins was examined to evaluate the osteoconductivity of the sternal pins. There were no significant differences between groups A and B in the sternal dehiscence rate (6.7 vs 4.4 %), sternal displacement rate (6.7 vs 2.2 %) or 12-month sternal fusion rate (63.3 vs 73.3 %). The CBDA around the sternal pins significantly increased between discharge and 12 months after surgery in group B (P < 0.001) but not in group A. These results show that u-HA-PLLA sternal pins exhibit certain osteoconductivity; however, both PLLA and u-HA-PLLA sternal pins provide comparable clinical outcomes regarding sternal stability and healing. PMID:23996506

  10. ACL reconstruction

    MedlinePlus

    ... Tissue taken from a donor is called an allograft. The procedure is usually performed with the help ... This increases the chance you may have a meniscus tear. ACL reconstruction may be used for these ...

  11. Scroll waves pinned to moving heterogeneities

    NASA Astrophysics Data System (ADS)

    Ke, Hua; Zhang, Zhihui; Steinbock, Oliver

    2015-03-01

    Three-dimensional excitable systems can self-organize vortex patterns that rotate around one-dimensional phase singularities called filaments. In experiments with the Belousov-Zhabotinsky reaction and numerical simulations, we pin these scroll waves to translating inert cylinders and demonstrate the controlled repositioning of their rotation centers. If the pinning site extends only along a portion of the filament, the phase singularity is stretched out along the trajectory of the heterogeneity, which effectively writes the singularity into the system. Its trailing end point follows the heterogeneity with a lower velocity. This velocity, its dependence on the placement of the anchor, and the shape of the filament are explained by a curvature flow model.

  12. Influential Factors of Z-pin Bridging Force

    NASA Astrophysics Data System (ADS)

    Li, Chenghu; Wu, Zhe; Meng, Zhijun; Li, Muchen

    2014-08-01

    The nine-pin bridging force experiments are conducted at room temperature (20 °C) and at 75 °C. A three-dimensional z-pin unit cell for finite element analysis is established to study the influential factors of the z-pin bridging force. The experimental results show that the z-pin bridging force at 75 °C is smaller than at 20 °C. The z-pin bridging force is highly dependent on the surface area of z-pin. Therefore, it is feasible that the bridging force can be enhanced by changing the surface area of z-pin. The study also shows that the lay-up sequences of laminates have an impact on the z-pin bridging force, and the maximum bridging force of z-pin rises with the increase elastic modules of the resin. The z-pin bridging force reduces with rise of temperature for two reasons: The elastic modulus and shear strength of the resin decrease with rise of temperature, forcing the bridging force to reduce and the resin makes some clamping effect on z-pin, pushing the bridging force to increase.

  13. [Eyebrow reconstruction].

    PubMed

    Baraër, F; Darsonval, V; Lejeune, F; Bochot-Hermouet, B; Rousseau, P

    2013-10-01

    The eyebrow is an essential anatomical area, from a social point of view, so its reconstruction, in case of skin defect, must be as meticulous as possible, with the less residual sequela. Capillary density extremely varies from one person to another and the different methods of restoration of this area should absolutely take this into consideration. We are going to review the various techniques of reconstruction, according to the sex and the surface to cover. PMID:23896574

  14. Statistical-summation theory of weak flux-line pins

    SciTech Connect

    Kerchner, H.R.

    1981-01-01

    A random array of flux-line-pinning defects is shown to produce a large, bulk pinning-force density even if the pins individually fail to satisfy the threshold criterion. By using a simplified model defect-FLL interaction, approximate expressions are obtained for the critical pinning-force density F/sub c/. The theory predicts that in materials with a weak pinning structure F/sub c/ depends only weakly on magnetic field except within narrow peaks near the upper and lower critical fields. The width of the peaks increases as the pinning is made stronger. A broad, dome-shaped peak in F/sub c/ and scaling-law behavior, both of which are usually associated with large F/sub c/ materials, is the strong-pinning limit of this theory.

  15. Thermal performance of a pin-fin assembly

    NASA Astrophysics Data System (ADS)

    Babus'hag, R. F.; Akintunde, K.; Probert, S. D.

    1995-02-01

    The steady-state forced-convective cooling of a horizontally based pin-fin assembly has been investigated experimentally. The circular pin-fins protruded vertically upward from a horizontal base plate. For each in-line or staggered combination of specified pin-fins and air-flow rate, the optimal spacing-to-diameter ratios corresponding to the maximum rate of heat dissipation from the array have been deduced. The effect of changing the thermal conductivity of the pin-fin material has been studied. Designers should aim to have a spacing-to-diameter ratio of 1.04, in the span-wise direction, for all pin-fin systems; whereas, the ratio for the pin-fins in the stream-wise direction will depend upon what fin material is used and whether or not the pin-fins are staggered or aligned.

  16. Rotary pin-in-maze discriminator

    DOEpatents

    Benavides, G.L.

    1997-05-06

    A discriminator apparatus and method that discriminates between a unique signal and any other (incorrect) signal are disclosed. The unique signal is a sequence of events; each event can assume one of two possible event states. Given the unique signal, a maze wheel is allowed to rotate fully in one direction. Given an incorrect signal, both the maze wheel and a pin wheel lock in position. 4 figs.

  17. Channelized coplanar waveguide pin-diode switches

    NASA Technical Reports Server (NTRS)

    Ponchak, G. E.; Simons, R. N.

    1989-01-01

    Three different types of p-i-n diode, reflective CPW switches are presented. The first two switches are the series and the shunt mounted diode switches. Each has achieved greater than 15 dB of isolation over a broad bandwidth. The third switch is a narrow band, high isolation switched filter which has achieved 19 dB of isolation. Equivalent circuits and measured performance for each switch is presented.

  18. Timing analysis of PWR fuel pin failures

    SciTech Connect

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. ); Straka, M. )

    1992-09-01

    Research has been conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin bumup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PFL/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design bumup. Using peaking factors commensurate widi actual bumups would result in longer intervals for both reactor designs. This document also contains appendices A through J of this report.

  19. Effects of mesh density and flow conditioning in simulating 7-pin wire wrapped fuel pins.

    SciTech Connect

    Smith, J. G.; Babin, B. R.; Pointer, W. D.; Fischer, P. F.

    2008-01-01

    In response to the goals outlined by the U.S. Department of Energy's Global Nuclear Energy Partnership program, Argonne National Laboratory has initiated an effort to create an integrated multi-physics multi-resolution thermal hydraulic simulation tool package for the evaluation of nuclear power plant design and safety. As part of this effort, the applicability of a variety of thermal hydraulic analysis methods for the prediction of heat transfer and fluid dynamics in the wire-wrapped fuel-rod bundles found in a fast reactor core is being evaluated. The work described herein provides an initial assessment of the capabilities of the general purpose commercial computational fluid dynamics code Star-CD for the prediction of fluid dynamic characteristics in a wire wrapped fast reactor fuel assembly. A 7-pin wire wrapped fuel rod assembly based on the dimensions of fuel elements in the concept Advanced Burner Test Reactor [1] was simulated for different mesh densities and domain configurations. A model considering a single axial span of the wire wrapped fuel assembly was initially used to assess mesh resolution effects. The influence of the inflow/outflow boundary conditions on the predicted flow fields in the single-span model were then investigated through comparisons with the central span region of models which included 3 and 5 spans. The change in grid refinement had minimal impact on the inter-channel exchange within the assembly resulting in roughly a 5 percent maximum difference. The central span of the 3-span and 5-span cases exhibits much higher velocities than the single span case,, with the largest deviation (15 to 20 percent) occurring furthest away from the wire spacer grids in the higher velocity regions. However, the differences between predicted flow fields in the 3-span and 5-span models are minimal.

  20. Performance measurements of hybrid PIN diode arrays

    SciTech Connect

    Jernigan, J.G.; Arens, J.F. . Space Sciences Lab.); Kramer, G. ); Collins, T.; Herring, J. ); Shapiro, S.L. ); Wilburn, C.D. )

    1990-05-01

    We report on the successful effort to develop hybrid PIN diode arrays and to demonstrate their potential as components of vertex detectors. Hybrid pixel arrays have been fabricated by the Hughes Aircraft Co. by bump bonding readout chips developed by Hughes to an array of PIN diodes manufactured by Micron Semiconductor Inc. These hybrid pixel arrays were constructed in two configurations. One array format having 10 {times} 64 pixels, each 120 {mu}m square, and the other format having 256 {times} 256 pixels, each 30 {mu}m square. In both cases, the thickness of the PIN diode layer is 300 {mu}m. Measurements of detector performance show that excellent position resolution can be achieved by interpolation. By determining the centroid of the charge cloud which spreads charge into a number of neighboring pixels, a spatial resolution of a few microns has been attained. The noise has been measured to be about 300 electrons (rms) at room temperature, as expected from KTC and dark current considerations, yielding a signal-to-noise ratio of about 100 for minimum ionizing particles. 4 refs., 13 figs.

  1. Fast PIN-diode beam loss monitors at Tevatron

    SciTech Connect

    Shiltsev, V.

    1997-07-01

    The article is devoted to results of fine time structure of particle losses in Tevatron with use of fast beam loss monitors (BLM) based on PIN-diodes. An ultimate goal of the new BLMs is to distinguish losses of protons and antiprotons from neighbor bunches with 132 ns bunch spacing in the Tevatron collider upgrade. The devices studied fit well to the goal as they can recognize even seven times closer - 18.9 ns - spaced bunches` losses in the Tevatron fixed target operation regime. We have measured main characteristics of the BLM as well as studied the proton losses over 10 decades of time scale - from dozen of minutes to dozen of nanoseconds. Power spectral density of the losses is compared with spectra of the proton beam motion.

  2. Design and evaluation of a 2D array PIN photodiode bump bonded to readout IC for the low energy x-ray detector.

    PubMed

    Yuk, Sunwoo; Park, Shin-Woong; Yi, Yun

    2006-01-01

    A 2D array radiation sensor, consisting of an array of PIN photodiodes bump bonded to readout integrated circuit (IC), has been developed for operation with low energy X-rays. The PIN photodiode array and readout IC for this system have been fabricated. The main performance measurements are the following: a few pA-scale leakage current, 350 pF junction capacitance, 30 microm-depth depletion layer and a 250 microm intrinsic layer at zero bias. This PIN photodiode array and readout IC were fabricated using a PIN photodiode process and standard 0.35 microm CMOS technology, respectively. The readout circuit is operated from a 3.3 V single power supply. Finally, a 2D array radiation sensor has been developed using bump bonding between the PIN photodiode and the readout electronics. PMID:17946079

  3. Sorting signals for PIN1 trafficking and localization.

    PubMed

    Marcote, María Jesús; Sancho-Andrés, Gloria; Soriano-Ortega, Esther; Aniento, Fernando

    2016-08-01

    PIN-FORMED (PIN) family proteins direct polar auxin transport based on their asymmetric (polar) localization at the plasma membrane. In the case of PIN1, it mainly localizes to the basal (rootward) plasma membrane domain of stele cells in root meristems. Vesicular trafficking events, such as clathrin-dependent PIN1 endocytosis and polar recycling, are probably the main determinants for PIN1 polar localization. However, very little is known about the signals which may be involved in binding the μ-adaptin subunit of clathrin adaptor complexes (APs) for sorting of PIN1 within clathrin-coated vesicles, which can determine its trafficking and localization. We have performed a systematic mutagenesis analysis to investigate putative sorting motifs in the hydrophilic loop of PIN1. We have found that a non-canonical motif, based in a phenylalanine residue, through the binding of μA(μ2)- and μD(μ3)-adaptin, is important for PIN1 endocytosis and for PIN1 traffcking along the secretory pathway, respectively. In addition, tyrosine-based motifs, which also bind different μ-adaptins, could also contribute to PIN1 trafficking and localization. PMID:27603315

  4. The effect of indole-3-carbinol on PIN1 and PIN2 in Arabidopsis roots.

    PubMed

    Katz, Ella; Nisani, Sophia; Sela, Mor; Behar, Hila; Chamovitz, Daniel A

    2015-01-01

    The phytochemical indole-3-carbinol is produced in Cruciferous plants upon tissue rapture and deters herbivores. We recently showed that indole-3-carbinol modulates auxin signaling in root tips. Here we present transcript profiling experiments which further reveal the influence of indole-3-carbinol on auxin signaling in root tips, and also show that I3C affects auxin transporters. Brief treatment with indole-3-carbinol led to a reduction in the amount of PIN1 and to mislocalization of PIN2. PMID:26252364

  5. The effect of indole-3-carbinol on PIN1 and PIN2 in Arabidopsis roots

    PubMed Central

    Katz, Ella; Nisani, Sophia; Sela, Mor; Behar, Hila; Chamovitz, Daniel A

    2015-01-01

    The phytochemical indole-3-carbinol is produced in Cruciferous plants upon tissue rapture and deters herbivores. We recently showed that indole-3-carbinol modulates auxin signaling in root tips. Here we present transcript profiling experiments which further reveal the influence of indole-3-carbinol on auxin signaling in root tips, and also show that I3C affects auxin transporters. Brief treatment with indole-3-carbinol led to a reduction in the amount of PIN1 and to mislocalization of PIN2. PMID:26252364

  6. A mechanism to pin skyrmions in chiral magnets.

    PubMed

    Liu, Ye-Hua; Li, You-Quan

    2013-02-20

    We propose a mechanism to pin skyrmions in chiral magnetic thin films by introducing local maxima of magnetic exchange strength as pinning centers. The local maxima can be realized by engineering the local density of itinerant electrons. The stationary properties and the dynamical pinning and depinning processes of an isolated skyrmion around a pinning center are studied. We carry out numerical simulations of the Landau-Lifshitz-Gilbert (LLG) equation and find a way to control the position of an isolated skyrmion in a pinning center lattice using electric current pulses. The results are verified by a Thiele equation analysis. We also find that the critical current to depin a skyrmion, which is estimated to have order of magnitude 10(7)-10(8) A m(-2), has linear dependence on the pinning strength. PMID:23339842

  7. A mechanism to pin skyrmions in chiral magnets

    NASA Astrophysics Data System (ADS)

    Liu, Ye-Hua; Li, You-Quan

    2013-02-01

    We propose a mechanism to pin skyrmions in chiral magnetic thin films by introducing local maxima of magnetic exchange strength as pinning centers. The local maxima can be realized by engineering the local density of itinerant electrons. The stationary properties and the dynamical pinning and depinning processes of an isolated skyrmion around a pinning center are studied. We carry out numerical simulations of the Landau-Lifshitz-Gilbert (LLG) equation and find a way to control the position of an isolated skyrmion in a pinning center lattice using electric current pulses. The results are verified by a Thiele equation analysis. We also find that the critical current to depin a skyrmion, which is estimated to have order of magnitude 107-108 A m-2, has linear dependence on the pinning strength.

  8. Contact stresses in pin-loaded orthotropic plates

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Klang, E. C.

    1984-01-01

    The effects of pin elasticity, friction, and clearance on the stresses near the hole in a pin-loaded orthotropic plate are described. The problem is modeled as a contact elasticity problem using complex variable theory, the pin and the plate being two elastic bodies interacting through contact. This modeling is in contrast to previous works which assumed that the pin is rigid or that it exerts a known cosinusoidal radial traction on the hole boundary. Neither of these approaches explicitly involves a pin. A collocation procedure and iteration were used to obtain numerical results for a variety of plate and pin elastic properties and various levels of friction and clearance. Collocation was used to enforce the boundary and iteration was used to find the contact and no-slip regions on the boundary. Details of the numerical scheme are discussed.

  9. Nanobubble stability induced by contact line pinning

    NASA Astrophysics Data System (ADS)

    Liu, Yawei; Zhang, Xianren

    2013-01-01

    The origin of surface nanobubbles stability is a controversial topic since nanobubbles were first observed. Here, we propose a mechanism that the three-phase contact line pinning, which results from the intrinsic nanoscale physical roughness or chemical heterogeneities of substrates, leads to stable surface nanobubbles. Using the constrained lattice density functional theory (LDFT) and kinetic LDFT, we prove thermodynamically and dynamically that the state with nanobubbles is in fact a thermodynamical metastable state. The mechanism consistent with the classical nucleation theory can interpret most of experimental characteristics for nanobubbles qualitatively, and predict relationships among the gas-side nanobubble contact angle, nanobubble size, and chemical potential.

  10. Current-voltage characteristics in collective pinning

    SciTech Connect

    de la Cruz, F.; Luzuriaga, J.; Martinez, E.N.; Osquiguil, E.J.

    1987-11-01

    The critical-current curves of amorphous samples which exhibit collective flux pinning have been analyzed, and it was found that the nonlinear part can be fitted by an expression of the form V(I)approx.((I-I/sub K/)/I/sub K/)/sup zeta/. This form, which could be due to critical behavior, is consistent with an interpretation of the unpinning of vortices in the collective regime as a phase transition between the static flux-line lattice (FLL) and the FLL in steady-state movement as has been proposed by Fisher.

  11. Semiconducting glasses with flux pinning inclusions

    DOEpatents

    Johnson, William L.; Poon, Siu-Joe; Duwez, Pol E.

    1981-01-01

    A series of amorphous superconducting glassy alloys containing 1% to 10% by volume of flux pinning crystalline inclusions have been found to have potentially useful properties as high field superconducting magnet materials. The alloys are prepared by splat cooling by the piston and anvil technique. The alloys have the composition (TM).sub.90-70 (M).sub.10-30 where TM is a transition metal selected from at least one metal of Groups IVB, VB, VIB, VIIB or VIIIB of the Periodic Table such as Nb, Mo, Ru, Zr, Ta, W or Re and M is at least one metalloid such as B, P, C, N, Si, Ge or Al.

  12. Capillary pinning of immiscible gravity currents in porous media

    NASA Astrophysics Data System (ADS)

    Zhao, B.; MacMinn, C. W.; Huppert, H. E.; Juanes, R.

    2013-12-01

    Gravity currents in porous media have attracted interest recently in the context of geological carbon dioxide (CO2) storage, where supercritical CO2 is captured from the flue gas of power plants and injected underground into deep saline aquifers. Capillarity can be important in the spreading and migration of the buoyant CO2 after injection because the typical pore size is very small (~10-100 microns), but the impact of capillarity on these flows is not well understood. Here, we study the impact of capillarity on the buoyant spreading of a finite gravity current of non-wetting fluid into a dense, wetting fluid in a vertically confined, horizontal aquifer. We show via simple, table-top experiments using glass bead packs that capillary pressure hysteresis pins a portion of the fluid-fluid interface. The horizontal extent of the pinned portion of the interface grows over time and this is responsible for ultimately stopping the spreading of the buoyant current after a finite distance. In addition, capillarity blunts the leading edge of the buoyant current. We demonstrate through micromodel experiments that the characteristic height of the nose of the current is controlled by the pore throat size distribution and the balance between capillarity and gravity. We develop a theoretical model that captures the evolution of immiscible gravity currents and predicts the maximum migration distance. Our work suggests that capillary pinning and capillary blunting exert an important control on finite-release gravity currents in the context of CO2 sequestration in deep saline aquifers. Gravity driven flow of a buoyant, nonwetting fluid (air) over a dense, wetting fluid (propylene glycol). Starting with a vertical interface between the fluids, the flow first undergoes a lock-exchange process. The process models a finite release problem after the dense fluid hits the left boundary. In contrast to finite release of a miscible current that spreads indefinitely, spreading of an immiscible

  13. Analysis of pin removal experiments conducted in an SCWR-like test lattice

    SciTech Connect

    Chawla, R.; Raetz, D.; Jordan, K. A.; Perret, G.

    2012-07-01

    A comprehensive program of integral experiments, largely based on the measurement of reaction rate distributions, was carried out recently on an SCWR-like fuel lattice in the central test zone of the PROTEUS zero-power research reactor at the Paul Scherrer Inst. in Switzerland. The present paper reports on the analysis of a complementary set of measurements, in which the reactivity effects of removing individual pins from the unperturbed, heterogeneously moderated reference lattice were investigated. It has been found that the detailed Monte Carlo modeling of the whole reactor using MCNPX is able - as in the case of the reaction rate distributions - to reproduce the experimental results for the pin removal worths within the achievable statistical accuracy. A comparison of reduced-geometry calculations between MCNPX and the deterministic LWR assembly code CASMO-4E has revealed certain discrepancies. On the basis of a reactivity decomposition analysis of the differences between the codes, it has been suggested that these could be due to CASMO-4E deficiencies in calculating the effect, upon pin removal, of the extra moderation in the neighboring fuel pins. (authors)

  14. Recent Developments on High Curie Temperature PIN-PMN-PT Ferroelectric Crystals

    PubMed Central

    Zhang, Shujun; Li, Fei; Sherlock, Nevin P.; Luo, Jun; Lee, Hyeong Jae; Xia, Ru; Meyer, Richard J.; Hackenberger, Wesley; Shrout, Thomas R.

    2011-01-01

    Pb(In0.5Nb0.5)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) ferroelectric crystals attracted extensive attentions in last couple years, due to their higher usage temperatures range (> 30°C) and coercive fields (~5kV/cm), meanwhile maintaining similar electromechanical couplings (k33> 90%) and piezoelectric coefficients (d33~1500pC/N), when compared to their binary counterpart Pb(Mg1/3Nb2/3)O3-PbTiO3. In this article, we reviewed recent developments on the PIN-PMN-PT single crystals, including the Bridgman crystal growth, dielectric, electromechanical, piezoelectric and ferroelectric behaviors as function of temperature and dc bias. Mechanical quality factor Q was studied as function of orientation and phase. Of particular interest is the dynamic strain, which related to the Q and d33, was found to be improved when compared to binary system, exhibiting the potential usage of PIN-PMN-PT in high power application. Furthermore, PIN-PMN-PT crystals exhibit improved thickness dependent properties, due to their small domain size, being on the order of 1μm. Finally, the manganese acceptor dopant in the ternary crystals was investigated and discussed briefly in this paper. PMID:21516190

  15. Performance Analysis of OCDMA Based on AND Detection in FTTH Access Network Using PIN & APD Photodiodes

    NASA Astrophysics Data System (ADS)

    Aldouri, Muthana; Aljunid, S. A.; Ahmad, R. Badlishah; Fadhil, Hilal A.

    2011-06-01

    In order to comprise between PIN photo detector and avalanche photodiodes in a system used double weight (DW) code to be a performance of the optical spectrum CDMA in FTTH network with point-to-multi-point (P2MP) application. The performance of PIN against APD is compared through simulation by using opt system software version 7. In this paper we used two networks designed as follows one used PIN photo detector and the second using APD photo diode, both two system using with and without erbium doped fiber amplifier (EDFA). It is found that APD photo diode in this system is better than PIN photo detector for all simulation results. The conversion used a Mach-Zehnder interferometer (MZI) wavelength converter. Also we are study, the proposing a detection scheme known as AND subtraction detection technique implemented with fiber Bragg Grating (FBG) act as encoder and decoder. This FBG is used to encode and decode the spectral amplitude coding namely double weight (DW) code in Optical Code Division Multiple Access (OCDMA). The performances are characterized through bit error rate (BER) and bit rate (BR) also the received power at various bit rate.

  16. Retractable pin dual in-line package test clip

    DOEpatents

    Bandzuch, Gregory S.; Kosslow, William J.

    1996-01-01

    This invention is a Dual In-Line Package (DIP) test clip for use when troubleshooting circuits containing DIP integrated circuits. This test clip is a significant improvement over existing DIP test clips in that it has retractable pins which will permit troubleshooting without risk of accidentally shorting adjacent pins together when moving probes to different pins on energized circuits or when the probe is accidentally bumped while taking measurements.

  17. Retractable pin dual in-line package test clip

    SciTech Connect

    Bandzuch, G.S.; Kosslow, W.J

    1993-12-31

    This invention is a Dual In-line Package (DIP) test clip for use when troubleshooting circuits containing DIP integrated circuits. This test clip is a significant improvement over existing DIP test clips in that it has retractable pins which will permit troubleshooting without risk of accidentally shorting adjacent pins together when moving probes to different pins on energized circuits or when the probe is accidentally bumped while taking measurements.

  18. Pinning synchronization of discrete dynamical networks with delay coupling

    NASA Astrophysics Data System (ADS)

    Cheng, Ranran; Peng, Mingshu; Zuo, Jun

    2016-05-01

    The purpose of this paper is to investigate the pinning synchronization analysis for nonlinear coupled delayed discrete dynamical networks with the identical or nonidentical topological structure. Based on the Lyapunov stability theory, pinning control method and linear matrix inequalities, several adaptive synchronization criteria via two kinds of pinning control method are obtained. Two examples based on Rulkov chaotic system are included to illustrate the effectiveness and verification of theoretical analysis.

  19. Reconstructing Validity

    ERIC Educational Resources Information Center

    Moss, Pamela A.

    2007-01-01

    In response to Lissitz and Samuelsen (2007), the author reconstructs the historical arguments for the more comprehensive unitary concept of validity and the principles of scientific inquiry underlying it. Her response is organized in terms of four questions: (a) How did validity in educational measurement come to be conceptualized as unitary, and…

  20. Vaginal reconstruction

    SciTech Connect

    Lesavoy, M.A.

    1985-05-01

    Vaginal reconstruction can be an uncomplicated and straightforward procedure when attention to detail is maintained. The Abbe-McIndoe procedure of lining the neovaginal canal with split-thickness skin grafts has become standard. The use of the inflatable Heyer-Schulte vaginal stent provides comfort to the patient and ease to the surgeon in maintaining approximation of the skin graft. For large vaginal and perineal defects, myocutaneous flaps such as the gracilis island have been extremely useful for correction of radiation-damaged tissue of the perineum or for the reconstruction of large ablative defects. Minimal morbidity and scarring ensue because the donor site can be closed primarily. With all vaginal reconstruction, a compliant patient is a necessity. The patient must wear a vaginal obturator for a minimum of 3 to 6 months postoperatively and is encouraged to use intercourse as an excellent obturator. In general, vaginal reconstruction can be an extremely gratifying procedure for both the functional and emotional well-being of patients.

  1. Project Reconstruct.

    ERIC Educational Resources Information Center

    Helisek, Harriet; Pratt, Donald

    1994-01-01

    Presents a project in which students monitor their use of trash, input and analyze information via a database and computerized graphs, and "reconstruct" extinct or endangered animals from recyclable materials. The activity was done with second-grade students over a period of three to four weeks. (PR)

  2. NEBA-3 pin and cermet hybrid bimodal reactor

    SciTech Connect

    Weitzberg, A.; Josloff, A.T.; Mondt, J.F.

    1995-12-31

    Early in 1994 a bimodal (power and propulsion) reactor concept that made use of two different fuel types was identified. UN pin fuel was selected for long lifetime to produce electricity, and UO{sub 2}-W cermet was selected for short-time high-temperature propulsion. During the last year the concept has been refined and analyzed as part of the DOE contribution to the joint Air Force Phillips Laboratory-Department of Energy Bimodal Program. With the exception of refractory metal vacuum gaps between the components containing hydrogen propellant and the refractory metal components containing lithium, and high temperature liquid metal-gas heat exchangers, the concept identified as Nuclear Engine for Bimodal Applications (NEBA)-3 uses previously developed and demonstrated technologies, including high efficiency closed Brayton cycle turboalternator-compressors for power production. Using near-term technology NEBA-3 can, as an upper stage to an Atlas IIAS launch vehicle, provide propulsion with specific impulse of about 850 seconds at thrusts of 90 to 925 Newtons, and 10 kilowatts of electricity for ten years. Based on previous cost estimates by DOE and NASA, a minimum program could deliver a flight system such as NEBA-3 within six years at a cost of from $500 to $700 million. The US space reactor power and propulsion community now has the technical capability to deliver such a system early in the next century.

  3. Percutaneous Pinning of Fifth Carpal–Metacarpal Fracture–Dislocations: An Alternative Pin Trajectory

    PubMed Central

    Lee, Sue Y.; Raphael, James S.

    2008-01-01

    Traditional management of unstable fourth and fifth carpal–metacarpal (CMC) fracture–dislocations (fx–dislocs) of the hand includes closed reduction and percutaneous pinning (CRPP) versus open reduction internal fixation (ORIF). Traditional trajectory of pin placement is toward the base of the hook of the hamate. Our case series of CMC fx–dislocs treated with this trajectory led to the development of ulnar deep motor branch symptoms (sxs). We attempt to propose an alternative trajectory that could lower the chance of iatrogenic injury. Five fresh frozen cadaveric specimens underwent percutaneous pinning of the fifth CMC joint using fluoroscopic guidance. Each cadaver was dissected, and the proximity of the deep motor branch of the ulnar nerve was measured in relation to a pin that penetrated the volar cortex. Our results confirm the close proximity of the deep motor branch of the ulnar nerve to the volar cortex of the hamate and demonstrate the potential for iatrogenic injury during CRPP of the fifth CMC fx–dislocs, especially with penetration of the volar cortex. By demonstrating the close proximity of the deep motor branch to the volar cortex of the hamate in cadavers, we highlight the potential for iatrogenic injury with CRPP of CMC fx–dislocs as seen in our case series. We recommend a more midaxial starting point on the proximal metacarpal with a trajectory aimed at the midbody of the hamate to prevent penetration of the hamate volar cortex and limit the chances of iatrogenic injury. PMID:18780105

  4. Percutaneous pinning of fifth carpal-metacarpal fracture-dislocations: an alternative pin trajectory.

    PubMed

    Saing, Minn H; Lee, Sue Y; Raphael, James S

    2008-09-01

    Traditional management of unstable fourth and fifth carpal-metacarpal (CMC) fracture-dislocations (fx-dislocs) of the hand includes closed reduction and percutaneous pinning (CRPP) versus open reduction internal fixation (ORIF). Traditional trajectory of pin placement is toward the base of the hook of the hamate. Our case series of CMC fx-dislocs treated with this trajectory led to the development of ulnar deep motor branch symptoms (sxs). We attempt to propose an alternative trajectory that could lower the chance of iatrogenic injury. Five fresh frozen cadaveric specimens underwent percutaneous pinning of the fifth CMC joint using fluoroscopic guidance. Each cadaver was dissected, and the proximity of the deep motor branch of the ulnar nerve was measured in relation to a pin that penetrated the volar cortex. Our results confirm the close proximity of the deep motor branch of the ulnar nerve to the volar cortex of the hamate and demonstrate the potential for iatrogenic injury during CRPP of the fifth CMC fx-dislocs, especially with penetration of the volar cortex. By demonstrating the close proximity of the deep motor branch to the volar cortex of the hamate in cadavers, we highlight the potential for iatrogenic injury with CRPP of CMC fx-dislocs as seen in our case series. We recommend a more midaxial starting point on the proximal metacarpal with a trajectory aimed at the midbody of the hamate to prevent penetration of the hamate volar cortex and limit the chances of iatrogenic injury. PMID:18780105

  5. The Scaling Rule and Fluxon Core Pinning in a High-Field Superconductor with Artificially Introduced Pins

    NASA Astrophysics Data System (ADS)

    Cooley, Lance David

    Flux pinning affects virtually every aspect of high-field superconductivity. Its fundamental mechanism(s) are in principle derived from a complicated theory, but are in practice generally accessed through measuring the field dependence of the bulk flux pinning force (F _{p}(B)). The central piece of information is the shape of the F_{p }(B) curve: It is generally accepted that if, and only if, the curve's shape is constant while the temperature or pin dimension changes, one pinning mechanism is dominant (the 'scaling rule'). During the course of this thesis, we established that the shape of F_{p}(B) is affected by the statistical distribution of the elementary pinning forces (f_{p}). Contrary to prior beliefs, it was concluded that the shape of the bulk pinning force curve for fluxon core pinning is constant, when the distribution is broad, only if the microstructure is fractal. The peak of the F_ {p}(B) curve occurs at a lower field prior models predict, regardless of whether the shape of the curve is constant. When the distribution is narrow, a constant shape occurs, and has the shape predicted for core pinning and direct summation. Thus, the bulk pinning force curve and the elementary pinning mechanism are directly related by the scaling rule only when the f_ {p} distribution is narrow. Within this context, core pinning has been investigated with a specially fabricated Nb-Ti composite having artificially introduced pins, for which the f_{p } distribution is as narrow as can be made. By design, core pinning should be dominant; the shape of the F_{p}(B) curve does not, however, have the predicted form. The results can be explained by a new pinning mechanism, which incorporates the proximity effect and an anisotropic fluxon core, as proposed by Gurevich. It is concluded that the shape of the bulk pinning force curve is very sensitive to the proximity effect, and it can have a peak at a higher field than was previously thought possible for core pinning. The scaling

  6. Convex accelerated maximum entropy reconstruction

    NASA Astrophysics Data System (ADS)

    Worley, Bradley

    2016-04-01

    Maximum entropy (MaxEnt) spectral reconstruction methods provide a powerful framework for spectral estimation of nonuniformly sampled datasets. Many methods exist within this framework, usually defined based on the magnitude of a Lagrange multiplier in the MaxEnt objective function. An algorithm is presented here that utilizes accelerated first-order convex optimization techniques to rapidly and reliably reconstruct nonuniformly sampled NMR datasets using the principle of maximum entropy. This algorithm - called CAMERA for Convex Accelerated Maximum Entropy Reconstruction Algorithm - is a new approach to spectral reconstruction that exhibits fast, tunable convergence in both constant-aim and constant-lambda modes. A high-performance, open source NMR data processing tool is described that implements CAMERA, and brief comparisons to existing reconstruction methods are made on several example spectra.

  7. ACL reconstruction - discharge

    MedlinePlus

    Anterior cruciate ligament reconstruction - discharge; ACL reconstruction - discharge ... had surgery to reconstruct your anterior cruciate ligament (ACL). The surgeon drilled holes in the bones of ...

  8. Epigallocatechin-gallate Suppresses Tumorigenesis by Directly Targeting Pin1

    SciTech Connect

    Urusova, Darya V.; Shim, Jung-Hyun; Kim, Dong Joon; Jung, Sung Keun; Zykova, Tatyana A.; Carper, Andria; Bode, Ann M.; Dong, Zigang

    2011-09-01

    The most active anticancer component in green tea is epigallocatechin-3-gallate (EGCG). The human peptidyl prolyl cis/trans isomerase (Pin1) plays a critical role in oncogenic signaling. Herein, we report the X-ray crystal structure of the Pin1/EGCG complex resolved at 1.9 Å resolution. Notably, the structure revealed the presence of EGCG in both the WW and PPIase domains of Pin1. The direct binding of EGCG with Pin1 was confirmed and the interaction inhibited Pin1 PPIase activity. In addition, proliferation of cells expressing Pin1 was inhibited and tumor growth in a xenograft mouse model was suppressed. The binding of EGCG with Arg17 in the WW domain prevented the binding of c-Jun, a well-known Pin1 substrate. EGCG treatment corresponded with a decreased abundance of cyclin D1 and diminution of 12-O-tetradecanoylphorbol-l3-acetate–induced AP-1 or NF-κB promoter activity in cells expressing Pin1. Overall, these results showed that EGCG directly suppresses the tumor-promoting effect of Pin1.

  9. Contact line pinning and the relationship between nanobubbles and substrates.

    PubMed

    Liu, Yawei; Wang, Jianjun; Zhang, Xianren; Wang, Wenchuan

    2014-02-01

    We report a theoretical study of nanobubble stabilization on a substrate by contact line pinning. In particular, we predict the magnitude of the pinning force required to stabilize a nanobubble and the threshold values of the pinning force that the substrate can provide. We show that the substrate chemistry and the local structures of substrate heterogeneity together determine whether or not surface nanobubbles are stable. We find that for stable nanobubbles, the contact angles are independent of substrate chemistry as its effects are cancelled out by the pinning effect. This prediction is in agreement with available experimental data. PMID:24511966

  10. Positioning and locking device for fuel pin to grid attachment

    DOEpatents

    Frick, Thomas M.; Wineman, Arthur L.

    1976-01-01

    A positioning and locking device for fuel pin to grid attachment provides an inexpensive means of positively positioning and locking the individual fuel pins which make up the driver fuel assemblies used in nuclear reactors. The device can be adapted for use with a currently used attachment grid assembly design and insures that the pins remain in their proper position throughout the in-reactor life of the assembly. This device also simplifies fuel bundle assembly in that a complete row of fuel pins can be added to the bundle during each step of assembly.

  11. Contact line pinning and the relationship between nanobubbles and substrates

    NASA Astrophysics Data System (ADS)

    Liu, Yawei; Wang, Jianjun; Zhang, Xianren; Wang, Wenchuan

    2014-02-01

    We report a theoretical study of nanobubble stabilization on a substrate by contact line pinning. In particular, we predict the magnitude of the pinning force required to stabilize a nanobubble and the threshold values of the pinning force that the substrate can provide. We show that the substrate chemistry and the local structures of substrate heterogeneity together determine whether or not surface nanobubbles are stable. We find that for stable nanobubbles, the contact angles are independent of substrate chemistry as its effects are cancelled out by the pinning effect. This prediction is in agreement with available experimental data.

  12. Heat transfer in a fuel pin shipping container. [IDENT 1578

    SciTech Connect

    Ingham, J.G.

    1980-11-11

    Maximum cladding temperatures occur when the IDENT 1578 fuel pin shipping container is installed in the T-3 Cask. The maximum allowable cladding temperature of 800/sup 0/F is reached when the rate of energy deposited in the 19-pin basket reaches 400 watts. Since 45% of the energy which is generated in the fuel escapes the 19-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 400/.55 = 727 watts. Similarly, the maximum allowable cladding temperature of 800/sup 0/F is reached when the rate of energy deposited in the 40-pin basket reaches 465 watts. Since 33% of the energy which is generated in the fuel escapes the 40-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 465/.66 = 704 watts. The IDENT 1578 fuel pin shipping container therefore meets its thermal design criteria. IDENT 1578 can handle fuel pins with a decay heat load of 600 watts while maintaining the maximum fuel pin cladding temperature below 800/sup 0/F. The emissivities which were determined from the test results for the basket tubes and container are relatively low and correspond to new, shiny conditions. As the IDENT 1578 container is exposed to high temperatures for extended periods of time during the transportation of fuel pins, the emissivities will probably increase. This will result in reduced temperatures.

  13. Thermal analysis of the FSP-1 fuel pin irradiation test

    SciTech Connect

    Lyon, W.F. III.

    1990-07-25

    Thermal analysis of a pin from the FSP-1 fuels irradiation test has been completed. The purpose of the analysis was to provide predictions of fuel pin temperatures, determine the flow regime within the lithium annulus of the test assembly, and provide a standardized model for a consistent basis of comparison between pins within the test assembly. The calculations have predicted that the pin is operating at slightly above the test design temperatures and that the flow regime within the lithium annulus is a laminar buoyancy driven flow. 7 refs., 5 figs.

  14. Effects of pin shape and array orientation on heat transfer and pressure loss in pin fin arrays

    NASA Astrophysics Data System (ADS)

    Metzger, D. E.; Fan, C. S.; Haley, S. W.

    1984-01-01

    In order to reduce the cooling airflow required by gas turbine blades, two families of pin fin array geometries which may potentially improve such air-cooled turbine blade airfoils' internal cooling performance are experimentally studied. One family uses circular cross section pins with various array orientations relative to the mean flow direction. The other family employs pins with an oblong cross section, again with various orientations. Heat transfer and pressure loss results indicate that the use of circular pins whose array orientation varies between the staggered and the inline can, in some cases, increase heat transfer while decreasing pressure loss. Elongated pins increased heat transfer, but with increased pressure loss. Pin surface heat transfer coefficients are double the endwall values.

  15. Optimizing Dynamical Network Structure for Pinning Control

    PubMed Central

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-01-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights. PMID:27067020

  16. Optimizing Dynamical Network Structure for Pinning Control.

    PubMed

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-01-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights. PMID:27067020

  17. Optimizing Dynamical Network Structure for Pinning Control

    NASA Astrophysics Data System (ADS)

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-04-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights.

  18. Breast Reconstruction After Mastectomy

    MedlinePlus

    ... around the cancer removed (lumpectomy or breast-conserving surgery) might not need reconstruction, but sometimes they do. Breast reconstruction is done by a plastic surgeon. Should I have breast reconstruction? Breast reconstruction ...

  19. Enhanced flux-pinning properties in superconducting YBa2Cu3O(7-delta) thin films with nanoengineering

    NASA Astrophysics Data System (ADS)

    Tsai, Chen-Fong

    Since the discovery of the high temperature superconductor YBa2Cu3O7-delta (YBCO), with transition temperature (Tc = 77 K), above liquid nitrogen point in 1987 many research projects have been dedicated to enhancing the high field performance of this material for practical applications. The 2 nd generation YBCO-based coated conductors are believed to be the most promising approach for commercial applications including power transmission, motors, generators, and high field magnets. With the advances of nanotechnologies, different nanoengineering methods have been demonstrated to enhance the performance of YBCO thin films, include doping with 0-dimensional (0-D) self-assembled nanoparticles, 1-dimensional (1-D) nanorods, and 2-dimensional (2-D) nanolayers. Furthermore, dopants with ferromagnetic properties are also reported to provide enhanced pinning effects by Lorentz force, especially under high-applied magnetic fields. The principle of these methods is to generate high-density defects at the heterogeneous interfaces as artificial pinning centers in an effort to improve the flux-pinning properties. The morphology and dimensions of the nanoinclusions play an important role in pining enhancement. Optimized pinning structures are likely to be located at energetically favorable vortex cores, which form a triangular lattice with dimensions close to the YBCO coherence length xi (xiab ~ 4 nm; xic ~ 0.5 nm at 77 K.) However, it is challenging to achieve small dimensional nanodopants in the vapor deposited YBCO thin films. The purpose of this research is to utilize nanoengineering methods to produce optimized pinning structure in YBCO thin films. In this thesis, we systematically study the effects of different nanoinclusions on the flux-pinning properties of YBCO thin films. The 0-D ferromagnetic Fe 2O3 and CoFe2O4 nanoparticles, 2-D CeO2 multilayers, and tunable vertically aligned nanocomposites (VAN) of (Fe2O3)x:(CeO2) 1-x and (CoFe2O4)x:(CeO2) 1-x systems are introduced

  20. Heat transfer coefficients for staggered arrays of short pin fins

    NASA Technical Reports Server (NTRS)

    Vanfossen, G. J.

    1981-01-01

    Short pin fins are often used to increase that heat transfer to the coolant in the trailing edge of a turbine blade. Due primarily to limits of casting technology, it is not possible to manufacture pins of optimum length for heat transfer purposes in the trailing edge region. In many cases the pins are so short that they actually decrease the total heat transfer surface area compared to a plain wall. A heat transfer data base for these short pins is not available in the literature. Heat transfer coefficients on pin and endwall surfaces were measured for several staggered arrays of short pin fins. The measured Nusselt numbers when plotted versus Reynolds numbers were found to fall on a single curve for all surfaces tested. The heat transfer coefficients for the short pin fins (length to diameter ratios of 1/2 and 2) were found to be about a factor of two lower than data from the literature for longer pin arrays (length to diameter ratios of about 8).

  1. Heat transfer coefficients for staggered arrays of short pin fins

    NASA Technical Reports Server (NTRS)

    Vanfossen, G. J.

    1981-01-01

    Short pin fins are often used to increase the heat transfer to the coolant in the trailing edge of a turbine blade. Due primarily to limits of casting technology, it is not possible to manufacture pins of optimum length for heat transfer purposes in the trailing edge region. In many cases the pins are so short that they actually decrease the total heat transfer surface area compared to a plain wall. A heat transfer data base for these short pins is not available in the literature. Heat transfer coefficients on pin and endwall surfaces were measured for several staggered arrays of short pin fins. The measured Nusselt numbers when plotted versus Reynolds numbers were found to fall on a single curve for all surfaces tested. The heat transfer coefficients for the short pin fins (length to diameter ratios of 1/2 and 2) were found to be about a factor of two lower than data from the literature for longer pin arrays (length to diameter ratios of about 8).

  2. Percutaneous pinning of fractures of the distal radius.

    PubMed

    Alm-Paulsen, Paal Sandoe; Rod, Oyvind; Rød, Kristian; Rajabi, Benjamin; Russwurm, Harald; Finsen, Vilhjalmur

    2012-09-01

    Reduction of fractures of the distal radius is often supplemented with percutaneous pinning, but there is little evidence that this affects the clinical outcome. A total of 43 patients with pinned, and 296 with conservatively-treated, fractures were reviewed a mean of 6 (range 3-13) years after injury. We found controls among the conservatively-treated patients who matched 30 of the patients with pinned fractures with respect to age, sex, trauma energy, and radiographic measurements at injury. Clinical and radiological results of the two groups were compared and contrasted. There was a trend for better radiological results in patients with pinned fractures, but not significantly so, and no difference in clinical variables. We identified seven published randomised studies in which pinning was compared with reduction and plaster of Paris alone. Most reported better radiological results at review. The three smallest studies with the shortest follow-up reported better clinical outcome for pinned fractures, while the remaining four studies found no significant clinical benefit from pinning. Although the radiological results were improved by percutaneous pinning in addition to reduction and plaster of Paris, the clinical outcome in extra-articular and simple intra-articular fractures seemed unaffected. PMID:22694081

  3. FSW of Tapered Thickness Welds using an Adjustable Pin Tool

    NASA Technical Reports Server (NTRS)

    Adams, Glynn; Venable, Richard; Lawless, Kirby; Smelser, Jerry (Technical Monitor)

    2002-01-01

    This viewgraph presentation describes the advantages of tapered thickness welds in FSW (friction stir welding), the structure of FSW welds, the adjustable pin tool used in FSW. Other topics described include compliance and temperature measurement in a FSW system, loads and torque upon the pin tool and its ability to penetrate different metals, and the results and metallurgy of FSW welds.

  4. Alignment tool facilitates pin placement on irregular horizontal surfaces

    NASA Technical Reports Server (NTRS)

    Boyle, J. V.

    1966-01-01

    Alignment tool facilitates spotting and cementing plastic pins on the true vertical to irregular concave and convex surfaces. The tool consists of a wood tripod with individually adjustable legs, a wood block with a hole for placing the pins and two spirit levels at a 90 degree angle for easy alignment.

  5. 41. VIEW OF WEST BASCULE LEAF LOCKING PINS IN EXTENDED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. VIEW OF WEST BASCULE LEAF LOCKING PINS IN EXTENDED POSITION - PINS FIT INTO MATCHING BUSHINGS ON THE EAST LEAF AND SECURE THE EAST AND WEST SECTIONS WHEN THE BRIDGE IS DOWN. - Tomlinson Bridge, Spanning Quinnipiac River at Forbes Street (U.S. Route 1), New Haven, New Haven County, CT

  6. Optical fuel pin scanner. [Patent application; for reading identifications

    DOEpatents

    Kirchner, T.L.; Powers, H.G.

    1980-12-09

    This patent relates to an optical identification system developed for post-irradiation disassembly and analysis of fuel bundle assemblies. The apparatus is designed to be lowered onto a stationary fuel pin to read identification numbers or letters imprinted on the circumference of the top fuel pin and cap. (DLC)

  7. The pin-amalgam restoration. Part 1. A review.

    PubMed

    Evans, J R; Wetz, J H

    1977-01-01

    A review of the literature indicates that the use of pins to support amalgam or cast gold restorations in advanced caries in posterior teeth is a quick and relatively inexpensive method of restoring teeth otherwise doomed to extraction. However, the use of pins demands a careful and skillful dentist who understands the morphology of these teeth and the proper use of the materials if injury to the pulp, accidental perforations, crazing of the dentin, and splitting of teeth are to be prevented. Until more objective and controlled studies are completed, the use of cemented pins vs. self-threading pins remains a matter of empirical and personal preference. It is clear that success in the use of any pin or pins depends more on the dentist's skill and judgment than on the particular type of pin technique used. In order to more objectively evaluate the use of pin-amalgam restorations, Part 11 of this study will analyze the results obtained in the Clinic at Tufts University School of Dental Medicine. PMID:318695

  8. Destabilizing interactions among [PSI(+)] and [PIN(+)] yeast prion variants.

    PubMed Central

    Bradley, Michael E; Liebman, Susan W

    2003-01-01

    The yeast Sup35 and Rnq1 proteins can exist in either the noninfectious soluble forms, [psi-] or [pin-], respectively, or the multiple infectious amyloid-like forms called [PSI+] or [PIN+] prion variants (or prion strains). It was previously shown that [PSI+] and [PIN+] prions enhance one another's de novo appearance. Here we show that specific prion variants of [PSI+] and [PIN+] disrupt each other's stable inheritance. Acquiring [PSI+] often impedes the inheritance of particular [PIN+] variants. Conversely, the presence of some [PIN+] variants impairs the inheritance of weak [PSI+] but not strong [PSI+] variants. These same [PIN+] variants generate a single-dot fluorescence pattern when a fusion of Rnq1 and green fluorescent protein is expressed. Another [PIN+] variant, which forms a distinctly different multiple-dot fluorescence pattern, does not impair [PSI+] inheritance. Thus, destabilization of prions by heterologous prions depends upon the variants involved. These findings may have implications for understanding interactions among other amyloid-forming proteins, including those associated with certain human diseases. PMID:14704158

  9. Origin of pinning enhancement in a ferromagnet-superconductor bilayer

    NASA Astrophysics Data System (ADS)

    Cieplak, Marta Z.; Cheng, X. M.; Chien, C. L.; Sang, Hai

    2005-01-01

    Vortex pinning has been studied for the superconducting Nb film covering ferromagnetic Co /Pt multilayer with perpendicular magnetic anisotropy, in which the magnetization reversal proceeds via domain-wall motion. Large enhancement of pinning in the Nb film has been observed in the final stages of the reversal process, and we demonstrate that it is caused by residual uninverted dendrite-shaped magnetic domains.

  10. Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation

    PubMed Central

    Zhang, Yingjie; Rai, Madhulika; Wang, Cheng; Gonzalez, Cayetano; Wang, Hongyan

    2016-01-01

    Prefoldin is a molecular chaperone complex that regulates tubulin function in mitosis. Here, we show that Prefoldin depletion results in disruption of neuroblast polarity, leading to neuroblast overgrowth in Drosophila larval brains. Interestingly, co-depletion of Prefoldin and Partner of Inscuteable (Pins) leads to the formation of gigantic brains with severe neuroblast overgrowth, despite that Pins depletion alone results in smaller brains with partially disrupted neuroblast polarity. We show that Prefoldin acts synergistically with Pins to regulate asymmetric division of both neuroblasts and Intermediate Neural Progenitors (INPs). Surprisingly, co-depletion of Prefoldin and Pins also induces dedifferentiation of INPs back into neuroblasts, while depletion either Prefoldin or Pins alone is insufficient to do so. Furthermore, knocking down either α-tubulin or β-tubulin in pins- mutant background results in INP dedifferentiation back into neuroblasts, leading to the formation of ectopic neuroblasts. Overexpression of α-tubulin suppresses neuroblast overgrowth observed in prefoldin pins double mutant brains. Our data elucidate an unexpected function of Prefoldin and Pins in synergistically suppressing dedifferentiation of INPs back into neural stem cells. PMID:27025979