Laser welding closed-loop power control

DEFF Research Database (Denmark)

Bagger, Claus; Olsen, Flemming Ove

2003-01-01

A closed-loop control system is developed to maintain an even seam width on the root side of a laser weld by continually controlling the output laser power of a 1500 W CO2 laser.......A closed-loop control system is developed to maintain an even seam width on the root side of a laser weld by continually controlling the output laser power of a 1500 W CO2 laser....

IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence

Energy Technology Data Exchange (ETDEWEB)

Lewandowski, Matthew [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, 91191 Gif-sur-Yvette (France); Senatore, Leonardo, E-mail: matthew.lewandowski@ipht.fr, E-mail: senatore@stanford.edu [Stanford Institute for Theoretical Physics, Stanford University, Stanford, 94306 CA (United States)

2017-08-01

Because large-scale structure surveys may very well be the next leading sources of cosmological information, it is important to have a precise understanding of the cosmological observables; for this reason, the Effective Field Theory of Large-Scale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the so-called Einstein-de Sitter approximation, an approximation of the time dependence which is known to be accurate to better than one percent. However, in order to reach even higher accuracy, the full time dependence must be used. The computation with exact time dependence is sensitive to both infrared (IR) and ultraviolet (UV) effects in the loop integrands, and while these effects must cancel because of diffeomorphism invariance, they make numerical computation much less efficient. We provide a formulation of the one-loop, equal-time exact-time-dependence power spectrum of density perturbations which is manifestly free of these spurious IR and UV divergences at the level of the integrand. We extend our results to the total matter mode with clustering quintessence, show that IR and UV divergences cancel, and provide the associated IR- and UV-safe integrand. This also establishes that the consistency conditions are satisfied in this system. We then use our one-loop result to do an improved precision comparison of the two-loop dark-matter power spectrum with the Dark Sky N -body simulation.

Banded versus Single-sided bonded space maintainers: A Comparative Study

Directory of Open Access Journals (Sweden)

Sudhir Mittal

2018-01-01

Full Text Available Background: The present study is conducted to evaluate and compare the clinical performance of conventional band and loop space maintainer and fiber reinforced composite resin (FRCR space maintainers. Materials and Methods: A total of 45 extraction sites in the age group of 6–9 years having premature loss of primary molars or indicated for extraction were selected for the study. The patients were randomly divided into three groups as Group I, in which conventional band and loop space maintainer was given, Group II and Group III (FRCR, in which FRCR (everStick CandB and impregnated glass fibers (Interlig space maintainers were given, respectively. Patients were recalled at 3, 6, and 12-month interval for evaluation of all the three types of space maintainer. Results: Overall success rate of Group I was 86.7%, for Group II was 80%, and for Group III was 73.3% at the end of the study. Patient acceptability was significantly higher in Group II and Group III (FRCR as compared to Group I (Conventional band and loop. In Group I, cement loss and fracture of loop, whereas in Group II and Group III, debonding at enamel composite was the most common failure followed by debonding at fiber composite and fiber fracture. FRCR space maintainers were found to be cost-effective as compared to Group I. More linear changes and angular changes were recorded in Group I as compared to Group II and Group III but difference was not significant (P > 0.05. Conclusion: Only single (buccal surface application of FRCR space maintainers showed almost equal clinical efficacy compared to conventional band and loop space maintainer with significantly better patient acceptability, less cost, and time taken.

Endurance test for IR rig for RI production assembly (test procedure)

International Nuclear Information System (INIS)

Chung, Heung June; Ryu, Jeong Soo

2000-08-01

This test procedure details the test loop, test method, and test procedure for pressure drop, vibration and endurance test of IR Rig for RI production. From the pressure drop test, the hydraulic design requirements of the capsule are verified. HANARO limit condition is checked and the compatibility with HANARO core is verified. From flow induced vibration test vibration frequency and displacement are investigated. The wear of IR Rig is investigated through endurance test, and these data are used to evaluate the expected wear at maximum resident time of the IR Rig for RI production

Symmetry-improved 2PI approach to the Goldstone-boson IR problem of the SM effective potential

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Apostolos Pilaftsis

2016-05-01

Full Text Available The effective potential of the Standard Model (SM, from three loop order and higher, suffers from infrared (IR divergences arising from quantum effects due to massless would-be Goldstone bosons associated with the longitudinal polarizations of the W± and Z bosons. Such IR pathologies also hinder accurate evaluation of the two-loop threshold corrections to electroweak quantities, such as the vacuum expectation value of the Higgs field. However, these divergences are an artifact of perturbation theory, and therefore need to be consistently resummed in order to obtain an IR-safe effective potential. The so-called Two-Particle-Irreducible (2PI effective action provides a rigorous framework to consistently perform such resummations, without the need to resort to ad hoc subtractions or running into the risk of over-counting contributions. By considering the recently proposed symmetry-improved 2PI formalism, we address the problem of the Goldstone-boson IR divergences of the SM effective potential in the gaugeless limit of the theory. In the same limit, we evaluate the IR-safe symmetry-improved 2PI effective potential, after taking into account quantum loops of chiral fermions, as well as the renormalization of spurious custodially breaking effects triggered by fermionic Yukawa interactions. Finally, we compare our results with those obtained with other methods presented in the literature.

Liquid Lead-Bismuth Materials Test Loop

International Nuclear Information System (INIS)

Tcharnotskaia, Valentina; Ammerman, Curtt; Darling, Timothy; King, Joe; Li, Ning; Shaw, Don; Snodgrass, Leon; Woloshun, Keith

2002-01-01

We designed and built the Liquid Lead-Bismuth Materials Test Loop (MTL) to study the materials behavior in a flow of molten lead-bismuth eutectic (LBE). In this paper we present a description of the loop with main components and their functions. Stress distribution in the piping due to sustained, occasional and expansion loads is shown. The loop is designed so that a difference of 100 deg. C can be attained between the coldest and the hottest parts at a nominal flow rate of 8.84 GPM. Liquid LBE flow can be activated by a mechanical sump pump or by natural convection. In order to maintain a self-healing protective film on the surface of the stainless steel pipe, a certain concentration of oxygen has to be maintained in the liquid metal. We developed oxygen sensors and an oxygen control system to be implemented in the loop. The loop is outfitted with a variety of instruments that are controlled from a computer based data acquisition system. Initial experiments include preconditioning the loop, filling it up with LBE, running at uniform temperature and tuning the oxygen control system. We will present some preliminary results and discuss plans for the future tests. (authors)

Development of Cytoplasmic Male Sterile IR24 and IR64 Using CW-CMS/Rf17 System.

Science.gov (United States)

Toriyama, Kinya; Kazama, Tomohiko

2016-12-01

A wild-abortive-type (WA) cytoplasmic male sterility (CMS) has been almost exclusively used for breeding three-line hybrid rice. Many indica cultivars are known to carry restorer genes for WA-CMS lines and cannot be used as maintainer lines. Especially elite indica cultivars IR24 and IR64 are known to be restorer lines for WA-CMS lines, and are used as male parents for hybrid seed production. If we develop CMS IR24 and CMS IR64, the combination of F1 pairs in hybrid rice breeding programs will be greatly broadened. For production of CMS lines and restorer lines of IR24 and IR64, we employed Chinese wild rice (CW)-type CMS/Restorer of fertility 17 (Rf17) system, in which fertility is restored by a single nuclear gene, Rf17. Successive backcrossing and marker-assisted selection of Rf17 succeeded to produce completely male sterile CMS lines and fully restored restorer lines of IR24 and IR64. CW-cytoplasm did not affect agronomic characteristics. Since IR64 is one of the most popular mega-varieties and used for breeding of many modern varieties, the CW-CMS line of IR64 will be useful for hybrid rice breeding.

Activation of high and low affinity dopamine receptors generates a closed loop that maintains a conductance ratio and its activity correlate

Directory of Open Access Journals (Sweden)

Wulf-Dieter Christian Krenz

2013-10-01

Full Text Available Neuromodulators alter network output and have the potential to destabilize a circuit. The mechanisms maintaining stability in the face of neuromodulation are not well described. Using the pyloric network in the crustacean stomatogastric nervous system, we show that dopamine (DA does not simply alter circuit output, but activates a closed loop in which DA-induced alterations in circuit output consequently drive a change in an ionic conductance to preserve a conductance ratio and its activity correlate. DA acted at low affinity type 1 receptors (D1Rs to induce an immediate modulatory decrease in the transient potassium current (IA of a pyloric neuron. This, in turn, advanced the activity phase of that component neuron, which disrupted its network function and thereby destabilized the circuit. DA simultaneously acted at high affinity D1Rs on the same neuron to confer activity-dependence upon the hyperpolarization activated current (Ih such that the DA-induced changes in activity subsequently reduced Ih. This DA-enabled, activity-dependent, intrinsic plasticity exactly compensated for the modulatory decrease in IA to restore the IA:Ih ratio and neuronal activity phase, thereby closing an open loop created by the modulator. Activation of closed loops to preserve conductance ratios may represent a fundamental operating principle neuromodulatory systems use to ensure stability in their target networks.

IR-360 nuclear power plant safety functions and component classification

International Nuclear Information System (INIS)

Yousefpour, F.; Shokri, F.; Soltani, H.

2010-01-01

The IR-360 nuclear power plant as a 2-loop PWR of 360 MWe power generation capacity is under design in MASNA Company. For design of the IR-360 structures, systems and components (SSCs), the codes and standards and their design requirements must be determined. It is a prerequisite to classify the IR-360 safety functions and safety grade of structures, systems and components correctly for selecting and adopting the suitable design codes and standards. This paper refers to the IAEA nuclear safety codes and standards as well as USNRC standard system to determine the IR-360 safety functions and to formulate the principles of the IR-360 component classification in accordance with the safety philosophy and feature of the IR-360. By implementation of defined classification procedures for the IR-360 SSCs, the appropriate design codes and standards are specified. The requirements of specific codes and standards are used in design process of IR-360 SSCs by design engineers of MASNA Company. In this paper, individual determination of the IR-360 safety functions and definition of the classification procedures and roles are presented. Implementation of this work which is described with example ensures the safety and reliability of the IR-360 nuclear power plant.

IR-360 nuclear power plant safety functions and component classification

Energy Technology Data Exchange (ETDEWEB)

Yousefpour, F., E-mail: fyousefpour@snira.co [Management of Nuclear Power Plant Construction Company (MASNA) (Iran, Islamic Republic of); Shokri, F.; Soltani, H. [Management of Nuclear Power Plant Construction Company (MASNA) (Iran, Islamic Republic of)

2010-10-15

The IR-360 nuclear power plant as a 2-loop PWR of 360 MWe power generation capacity is under design in MASNA Company. For design of the IR-360 structures, systems and components (SSCs), the codes and standards and their design requirements must be determined. It is a prerequisite to classify the IR-360 safety functions and safety grade of structures, systems and components correctly for selecting and adopting the suitable design codes and standards. This paper refers to the IAEA nuclear safety codes and standards as well as USNRC standard system to determine the IR-360 safety functions and to formulate the principles of the IR-360 component classification in accordance with the safety philosophy and feature of the IR-360. By implementation of defined classification procedures for the IR-360 SSCs, the appropriate design codes and standards are specified. The requirements of specific codes and standards are used in design process of IR-360 SSCs by design engineers of MASNA Company. In this paper, individual determination of the IR-360 safety functions and definition of the classification procedures and roles are presented. Implementation of this work which is described with example ensures the safety and reliability of the IR-360 nuclear power plant.

Dynamical gluon masses in perturbative calculations at the loop level

International Nuclear Information System (INIS)

Machado, Fatima A.; Natale, Adriano A.

2013-01-01

Full text: In the phenomenology of strong interactions one always has to deal at some extent with the interplay between perturbative and non-perturbative QCD. On one hand, the former has quite developed tools, yielded by asymptotic freedom. On the other, concerning the latter, we nowadays envisage the following scenario: 1) There are strong evidences for a dynamically massive gluon propagator and infrared finite coupling constant; 2) There is an extensive and successful use of an infrared finite coupling constant in phenomenological calculations at tree level; 3) The infrared finite coupling improves the perturbative series convergence; 4) The dynamical gluon mass provides a natural infrared cutoff in the physical processes at the tree level. Considering this scenario it is natural to ask how these non-perturbative results can be used in perturbative calculations of physical observables at the loop level. Recent papers discuss how off-shell gauge and renormalization group invariant Green functions can be computed with the use of the Pinch Technique (PT), with IR divergences removed by the dynamical gluon mass, and using a well defined effective charge. In this work we improve the former results by the authors, which evaluate 1-loop corrections to some two- and three-point functions of SU(3) pure Yang-Mills, investigating the dressing of quantities that could account for an extension of loop calculations to the infrared domain of the theory, in a way applicable to phenomenological calculations. One of these improvements is maintaining the gluon propagator transverse in such a scheme. (author)

Automation of secondary loop operation in Indus-2 LCW plant

International Nuclear Information System (INIS)

Srinivas, L.; Pandey, R.M.; Yadav, R.P.; Gupta, S.; Gandhi, M.L.; Thakurta, A.C.

2013-01-01

Indus-2 Low Conductivity Water (LCW) plant has two loops, primary loop and secondary loop. The primary loop mainly supplies LCW to magnets, power supplies and RF systems at constant flow rate. The secondary loop extracts heat from the primary loop through heat exchangers to maintain the supply water temperature of the primary loop around a set value. The supply water temperature of the primary loop is maintained by operating the pumps and cooling towers in the secondary loop. The desired water flow rate in the secondary loop is met by the manual operation of the required number of the pumps. The automatic operation of the pumps and the cooling towers is proposed to replace the existing inefficient manual operation. It improves the operational reliability and ensures the optimum utilization of the pumps and the cooling towers. An algorithm has been developed using LabView programming to achieve optimized operation of the pumps and the cooling towers by incorporating First-In-First-Out (FIFO) logic. It also takes care of safety interlocks, and generates alarms. The program exchanges input and output signals of the plant using existing SCADA system. In this paper, the development of algorithm, its design and testing are elaborated. In the end, the results obtained thereof are discussed. (author)

One-loop Yukawa Couplings in Local Models

CERN Document Server

Conlon, Joseph P; Palti, Eran; 10.1007

2010-01-01

We calculate the one-loop Yukawa couplings and threshold corrections for supersymmetric local models of branes at singularities in type IIB string theory. We compute the corrections coming both from wavefunction and vertex renormalisation. The former comes in the IR from conventional field theory running and in the UV from threshold corrections that cause it to run from the winding scale associated to the full Calabi-Yau volume. The vertex correction is naively absent as it appears to correspond to superpotential renormalisation. However, we find that while the Wilsonian superpotential is not renormalised there is a physical vertex correction in the 1PI action associated to light particle loops.

One-loop Yukawa couplings in local models

International Nuclear Information System (INIS)

Conlon, Joseph P.; Goodsell, Mark; Palti, Eran

2010-07-01

We calculate the one-loop Yukawa couplings and threshold corrections for supersymmetric local models of branes at singularities in type IIB string theory. We compute the corrections coming both from wavefunction and vertex renormalisation. The former comes in the IR from conventional field theory running and in the UV from threshold corrections that cause it to run from the winding scale associated to the full Calabi-Yau volume. The vertex correction is naively absent as it appears to correspond to superpotential renormalisation. However, we find that while the Wilsonian superpotential is not renormalised there is a physical vertex correction in the 1PI action associated to light particle loops. (orig.)

One-loop Yukawa couplings in local models

Energy Technology Data Exchange (ETDEWEB)

Conlon, Joseph P. [Rudolf Peierls Center for Theoretical Physics, Oxford (United Kingdom); Balliol College, Oxford (United Kingdom); Goodsell, Mark [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Palti, Eran [Centre de Physique Theorique, Ecole Polytechnique, CNRS, Palaiseau (France)

2010-07-15

We calculate the one-loop Yukawa couplings and threshold corrections for supersymmetric local models of branes at singularities in type IIB string theory. We compute the corrections coming both from wavefunction and vertex renormalisation. The former comes in the IR from conventional field theory running and in the UV from threshold corrections that cause it to run from the winding scale associated to the full Calabi-Yau volume. The vertex correction is naively absent as it appears to correspond to superpotential renormalisation. However, we find that while the Wilsonian superpotential is not renormalised there is a physical vertex correction in the 1PI action associated to light particle loops. (orig.)

Aesthetic rehabilitation with multiple loop connectors

Directory of Open Access Journals (Sweden)

Ashish Kalra

2013-01-01

Full Text Available Patients with a missing tooth along with diastema have limited treatment options to restore the edentulous space. The use of a conventional fixed partial denture (FPD to replace the missing tooth may result in too wide anterior teeth leading to poor esthetics. The diastema resulting from the missing central incisors can be managed with implant-supported prosthesis or FPD with loop connectors. An old lady reported with chief complaints of missing upper anterior teeth due to trauma. Her past dental history revealed that she was having generalized spacing between her upper anterior teeth. Considering her esthetic requirement of maintaining the diastema between 12, 11, 22, and 21, the treatment option of 06 units porcelain fused to metal FPD from canine to canine with intermittent loop connectors between 21, 22, 11, 12 was planned. Connectors basically link different parts of FPDs. The modified FPD with loop connectors enhanced the natural appearance of the restoration, maintained the diastemas and the proper emergence profile, and preserve the remaining tooth structure of abutment teeth. This clinical report discussed a method for fabrication of a modified FPD with loop connectors to restore the wide span created by missing central incisors.

Light-like noncommutativity, light-front quantization and new light on UV/IR mixing

International Nuclear Information System (INIS)

Sheikh-Jabbari, M.M.; Tureanu, A.

2011-01-01

We revisit the problem of quantizing field theories on noncommutative Moyal space-time with light-like noncommutativity. To tackle the issues arising from noncommuting and hence nonlocal time, we argue that for this case light-front quantization procedure should be employed. In this appropriate quantization scheme we perform the non-planar loop analysis for the light-like noncommutative field theories. One of the important and peculiar features of light-front quantization is that the UV cutoff of the light-cone Hamiltonian manifests itself as an IR cutoff for the light-cone momentum, p + . Due to this feature, the naive results of covariant quantization for the light-like case allude to the absence of the UV/IR mixing in the light-front quantization. However, by a careful analysis of non-planar loop integrals we show that this is not the case and the UV/IR mixing persists. In addition, we argue in favour of the perturbative unitarity of light-like noncommutative field theories in the light-front quantization scheme.

Loop connectors in dentogenic diastema

Directory of Open Access Journals (Sweden)

Sanjna Nayar

2015-01-01

Full Text Available Patients with a missing tooth along with diastema have limited treatment options to restore the edentulous space. The use of a conventional fixed partial denture (FPD to replace the missing tooth may result in too wide anterior teeth leading to poor esthetics. Loss of anterior teeth with existing diastema may result in excess space available for pontic. This condition presents great esthetic challenge for prosthodontist. If implant supported prosthesis is not possible because of inadequate bone support, FPD along with loop connector may be a treatment option to maintain the diastema and provide optimal esthetic restoration. Here, we report a clinical case where FPD along with loop connector was used to achieve esthetic rehabilitation in maxillary anterior region in which midline diastema has been maintained.

Time evolution of the energy confinement time, internal inductance and effective edge safety factor on IR-T1 tokamak

International Nuclear Information System (INIS)

Salar Elahi, A; Ghoranneviss, M

2010-01-01

An attempt is made to investigate the time evolution of the energy confinement time, internal inductance and effective edge safety factor on IR-T1 tokamak. For this purpose, four magnetic pickup coils were designed, constructed and installed on the outer surface of the IR-T1 and then the Shafranov parameter (asymmetry factor) was obtained from them. On the other hand, also a diamagnetic loop was designed and installed on IR-T1 and poloidal beta was determined from it. Therefore, the internal inductance and effective edge safety factor were measured. Also, the time evolution of the energy confinement time was measured using the diamagnetic loop. Experimental results on IR-T1 show that the maximum energy confinement time (which corresponds to minimum collisions, minimum microinstabilities and minimum transport) is at low values of the effective edge safety factor (2.5 eff (a) i <0.72). The results obtained are in agreement with those obtained with the theoretical approach [1-5].

Study of the influence of Nb buffer layer on the exchange coupling induced at the Co/IrMn interface

Energy Technology Data Exchange (ETDEWEB)

Merino, I.L.C., E-mail: isabel5cas@gmail.com [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180 (Brazil); Figueiredo, L.C. [Instituto de Física, Universidade de Brasília, Brasília 70910-900 (Brazil); Passamani, E.C.; Nascimento, V.P. [Departamento de Física, Universidade Federal do Espírito Santo, Vitória 29075-910 (Brazil); Pelegrini, F. [Instituto de Física, Universidade Federal de Goiás, Goiânia 74560-900 (Brazil); Baggio Saitovitch, E. [Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro 22290-180 (Brazil)

2017-06-15

Highlights: • Nb buffer layer favors smooth/rough Co/IrMn interfaces, depending on its thickness. • Double and single-like hysteresis loop features depend on the Nb thickness. • Co uniaxial anisotropy induced exchange-bias in as-deposited sample. • Uniaxial and exchange-bias anisotropy directions depend on the Nb thickness. • Thicker Nb favors non-collinear anisotropies, while thinner Nb favors collinear. - Abstract: Hybrid Nb(t{sub Nb})/Co(10 nm)/IrMn(15 nm)/Nb(10 nm) heterostructured materials were prepared by DC Magnetron Sputtering and systematically studied by X-ray, magnetization and ferromagnetic resonance techniques. For thinner Nb buffer layer (≤10 nm), it was found that there is an inter-diffusion at Co/IrMn interface, which favors double-like hysteresis loop. For thicker Nb layers, however, a gradual transition from double to single-like hysteresis loops is observed and it is associated with the reduction of the Nb roughness, which also enhances the exchange coupling at the Co/IrMn interface. Nb grown on IrMn layer induces the formation of an NbIrMn alloy layer, while no evidence of inter-diffusion at the Co/Nb interface is observed. For rougher Nb buffer layers (t{sub Nb} < 50 nm), exchange bias and Co uniaxial anisotropies are pointing at the same direction (β∼zero), but for smoother Nb buffer layer (t{sub Nb} = 50 nm) a β angle of 150{sup o} is found. Exchange bias effect was measured in as-prepared and in field-cooled samples; being its presence, in as-prepared sample, attributed to the unidirectional anisotropy of the Co layer (its intensity is modified in case of sample with a CoIrMn alloy layer). Considering that the Si/Nb/Co/IrMn interfaces have different β values (t{sub Nb} = 35 and 50 nm), a study of the influence of magnetization direction, governed by exchange-biased layers, on superconducting properties of Nb films can be successfully done in this hybrid system.

Automatic numerical integration methods for Feynman integrals through 3-loop

International Nuclear Information System (INIS)

De Doncker, E; Olagbemi, O; Yuasa, F; Ishikawa, T; Kato, K

2015-01-01

We give numerical integration results for Feynman loop diagrams through 3-loop such as those covered by Laporta [1]. The methods are based on automatic adaptive integration, using iterated integration and extrapolation with programs from the QUADPACK package, or multivariate techniques from the ParInt package. The Dqags algorithm from QuadPack accommodates boundary singularities of fairly general types. PARINT is a package for multivariate integration layered over MPI (Message Passing Interface), which runs on clusters and incorporates advanced parallel/distributed techniques such as load balancing among processes that may be distributed over a network of nodes. Results are included for 3-loop self-energy diagrams without IR (infra-red) or UV (ultra-violet) singularities. A procedure based on iterated integration and extrapolation yields a novel method of numerical regularization for integrals with UV terms, and is applied to a set of 2-loop self-energy diagrams with UV singularities. (paper)

A Nodal-independent and tissue-intrinsic mechanism controls heart-looping chirality

Science.gov (United States)

Noël, Emily S.; Verhoeven, Manon; Lagendijk, Anne Karine; Tessadori, Federico; Smith, Kelly; Choorapoikayil, Suma; den Hertog, Jeroen; Bakkers, Jeroen

2013-11-01

Breaking left-right symmetry in bilateria is a major event during embryo development that is required for asymmetric organ position, directional organ looping and lateralized organ function in the adult. Asymmetric expression of Nodal-related genes is hypothesized to be the driving force behind regulation of organ laterality. Here we identify a Nodal-independent mechanism that drives asymmetric heart looping in zebrafish embryos. In a unique mutant defective for the Nodal-related southpaw gene, preferential dextral looping in the heart is maintained, whereas gut and brain asymmetries are randomized. As genetic and pharmacological inhibition of Nodal signalling does not abolish heart asymmetry, a yet undiscovered mechanism controls heart chirality. This mechanism is tissue intrinsic, as explanted hearts maintain ex vivo retain chiral looping behaviour and require actin polymerization and myosin II activity. We find that Nodal signalling regulates actin gene expression, supporting a model in which Nodal signalling amplifies this tissue-intrinsic mechanism of heart looping.

RTEL1 dismantles T loops and counteracts telomeric G4-DNA to maintain telomere integrity.

Science.gov (United States)

Vannier, Jean-Baptiste; Pavicic-Kaltenbrunner, Visnja; Petalcorin, Mark I R; Ding, Hao; Boulton, Simon J

2012-05-11

T loops and telomeric G-quadruplex (G4) DNA structures pose a potential threat to genome stability and must be dismantled to permit efficient telomere replication. Here we implicate the helicase RTEL1 in the removal of telomeric DNA secondary structures, which is essential for preventing telomere fragility and loss. In the absence of RTEL1, T loops are inappropriately resolved by the SLX4 nuclease complex, resulting in loss of the telomere as a circle. Depleting SLX4 or blocking DNA replication abolished telomere circles (TCs) and rescued telomere loss in RTEL1(-/-) cells but failed to suppress telomere fragility. Conversely, stabilization of telomeric G4-DNA or loss of BLM dramatically enhanced telomere fragility in RTEL1-deficient cells but had no impact on TC formation or telomere loss. We propose that RTEL1 performs two distinct functions at telomeres: it disassembles T loops and also counteracts telomeric G4-DNA structures, which together ensure the dynamics and stability of the telomere. Copyright © 2012 Elsevier Inc. All rights reserved.

First cytoplasmic loop of glucagon-like peptide-1 receptor can function at the third cytoplasmic loop position of rhodopsin.

Science.gov (United States)

Yamashita, Takahiro; Tose, Koji; Shichida, Yoshinori

2008-01-01

G protein-coupled receptors (GPCRs) are classified into several families based on their amino acid sequences. In family 1, GPCRs such as rhodopsin and adrenergic receptor, the structure-function relationship has been extensively investigated to demonstrate that exposure of the third cytoplasmic loop is essential for selective G protein activation. In contrast, much less is known about other families. Here we prepared chimeric mutants between Gt-coupled rhodopsin and Gi/Go- and Gs-coupled glucagon-like peptide-1 (GLP-1) receptor of family 2 and tried to identify the loop region that functions at the third cytoplasmic loop position of rhodopsin. We succeeded in expressing a mutant having the first cytoplasmic loop of GLP-1 receptor and found that this mutant activated Gi and Go efficiently but did not activate Gt. Moreover, the rhodopsin mutant having the first loop of Gs-coupled secretin receptor of family 2 decreased the Gi and Go activation efficiencies. Therefore, the first loop of GLP-1 receptor would share a similar role to the third loop of rhodopsin in G protein activation. This result strongly suggested that different families of GPCRs have maintained molecular architectures of their ancestral types to generate a common mechanism, namely exposure of the cytoplasmic loop, to activate peripheral G protein.

String states, loops and effective actions in noncommutative field theory and matrix models

Directory of Open Access Journals (Sweden)

Harold C. Steinacker

2016-09-01

Full Text Available Refining previous work by Iso, Kawai and Kitazawa, we discuss bi-local string states as a tool for loop computations in noncommutative field theory and matrix models. Defined in terms of coherent states, they exhibit the stringy features of noncommutative field theory. This leads to a closed form for the 1-loop effective action in position space, capturing the long-range non-local UV/IR mixing for scalar fields. The formalism applies to generic fuzzy spaces. The non-locality is tamed in the maximally supersymmetric IKKT or IIB model, where it gives rise to supergravity. The linearized supergravity interactions are obtained directly in position space at one loop using string states on generic noncommutative branes.

String states, loops and effective actions in noncommutative field theory and matrix models

Energy Technology Data Exchange (ETDEWEB)

Steinacker, Harold C., E-mail: harold.steinacker@univie.ac.at

2016-09-15

Refining previous work by Iso, Kawai and Kitazawa, we discuss bi-local string states as a tool for loop computations in noncommutative field theory and matrix models. Defined in terms of coherent states, they exhibit the stringy features of noncommutative field theory. This leads to a closed form for the 1-loop effective action in position space, capturing the long-range non-local UV/IR mixing for scalar fields. The formalism applies to generic fuzzy spaces. The non-locality is tamed in the maximally supersymmetric IKKT or IIB model, where it gives rise to supergravity. The linearized supergravity interactions are obtained directly in position space at one loop using string states on generic noncommutative branes.

UV-IR mixing in nonassociative Snyder ϕ4 theory

Science.gov (United States)

Meljanac, Stjepan; Mignemi, Salvatore; Trampetic, Josip; You, Jiangyang

2018-03-01

Using a quantization of the nonassociative and noncommutative Snyder ϕ4 scalar field theory in a Hermitian realization, we present in this article analytical formulas for the momentum-conserving part of the one-loop two-point function of this theory in D -, 4-, and 3-dimensional Euclidean spaces, which are exact with respect to the noncommutative deformation parameter β . We prove that these integrals are regularized by the Snyder deformation. These results indicate that the Snyder deformation does partially regularize the UV divergences of the undeformed theory, as it was proposed decades ago. Furthermore, it is observed that different nonassociative ϕ4 products can generate different momentum-conserving integrals. Finally, most importantly, a logarithmic infrared divergence emerges in one of these interaction terms. We then analyze sample momentum nonconserving integral qualitatively and show that it could exhibit IR divergence too. Therefore, infrared divergences should exist, in general, in the Snyder ϕ4 theory. We consider infrared divergences at the limit p →0 as UV/IR mixings induced by nonassociativity, since they are associated to the matching UV divergence in the zero-momentum limit and appear in specific types of nonassociative ϕ4 products. We also discuss the extrapolation of the Snyder deformation parameter β to negative values as well as certain general properties of one-loop quantum corrections in Snyder ϕ4 theory at the zero-momentum limit.

Operation of the hot test loop facilities

International Nuclear Information System (INIS)

Cheong, Moon Ki; Park, Choon Kyeong; Won, Soon Yeon; Yang, Sun Kyu; Cheong, Jang Whan; Cheon, Se Young; Song, Chul Hwa; Jeon, Hyeong Kil; Chang, Suk Kyu; Jeong, Heung Jun; Cho, Young Ro; Kim, Bok Duk; Min, Kyeong Ho

1994-12-01

The objective of this project is to obtain the available experimental data and to develop the measuring techniques through taking full advantage of the facilities. The facilities operated by the thermal hydraulics department have been maintained and repaired in order to carry out the thermal hydraulics tests necessary for providing the available data. The performance tests for double grid type bottom end piece which was improved on the debris filtering effectivity were performed using the PWR-Hot Test Loop. The CANDU-Hot Test Loop was operated to carry out the pressure drop tests and strength tests of fuel. The Cold Test Loop was used to obtain the local velocity data in subchannel within fuel bundle and to understand the characteristic of pressure drop required for improving the nuclear fuel and to develop the advanced measuring techniques. RCS Loop, which is used to measure the CHF, is presently under design and construction. B and C Loop is designed and constructed to assess the automatic depressurization safety system behavior. 4 tabs., 79 figs., 7 refs. (Author) .new

Impaired Insulin Signaling is Associated with Hepatic Mitochondrial Dysfunction in IR+/−-IRS-1+/− Double Heterozygous (IR-IRS1dh Mice

Directory of Open Access Journals (Sweden)

Andras Franko

2017-05-01

Full Text Available Mitochondria play a pivotal role in energy metabolism, but whether insulin signaling per se could regulate mitochondrial function has not been identified yet. To investigate whether mitochondrial function is regulated by insulin signaling, we analyzed muscle and liver of insulin receptor (IR+/−-insulin receptor substrate-1 (IRS-1+/− double heterozygous (IR-IRS1dh mice, a well described model for insulin resistance. IR-IRS1dh mice were studied at the age of 6 and 12 months and glucose metabolism was determined by glucose and insulin tolerance tests. Mitochondrial enzyme activities, oxygen consumption, and membrane potential were assessed using spectrophotometric, respirometric, and proton motive force analysis, respectively. IR-IRS1dh mice showed elevated serum insulin levels. Hepatic mitochondrial oxygen consumption was reduced in IR-IRS1dh animals at 12 months of age. Furthermore, 6-month-old IR-IRS1dh mice demonstrated enhanced mitochondrial respiration in skeletal muscle, but a tendency of impaired glucose tolerance. On the other hand, 12-month-old IR-IRS1dh mice showed improved glucose tolerance, but normal muscle mitochondrial function. Our data revealed that deficiency in IR/IRS-1 resulted in normal or even elevated skeletal muscle, but impaired hepatic mitochondrial function, suggesting a direct cross-talk between insulin signaling and mitochondria in the liver.

Leak Mitigation in Mechanically Pumped Fluid Loops for Long Duration Space Missions

Science.gov (United States)

Miller, Jennifer R.; Birur, Gajanana; Bame, David; Mastropietro, A. J.; Bhandari, Pradeep; Lee, Darlene; Karlmann, Paul; Liu, Yuanming

2013-01-01

Mechanically pumped fluid loops (MPFLs) are increasingly considered for spacecraft thermal control. A concern for long duration space missions is the leak of fluid leading to performance degradation or potential loop failure. An understanding of leak rate through analysis, as well as destructive and non-destructive testing, provides a verifiable means to quantify leak rates. The system can be appropriately designed to maintain safe operating pressures and temperatures throughout the mission. Two MPFLs on the Mars Science Laboratory Spacecraft, launched November 26, 2011, maintain the temperature of sensitive electronics and science instruments within a -40 deg C to 50 deg C range during launch, cruise, and Mars surface operations. With over 100 meters of complex tubing, fittings, joints, flex lines, and pumps, the system must maintain a minimum pressure through all phases of the mission to provide appropriate performance. This paper describes the process of design, qualification, test, verification, and validation of the components and assemblies employed to minimize risks associated with excessive fluid leaks from pumped fluid loop systems.

Interventions for maintaining nasogastric feeding after stroke: An integrative review of effectiveness and acceptability.

Science.gov (United States)

Mahoney, Catherine; Veitch, Linda

2018-02-01

To investigate the effectiveness and acceptability of interventions for maintaining nasogastric tubes in adult stroke patients. Internationally, incidence of cerebral vascular disease continues to increase and stroke is the largest cause of complex disability in adults. Dysphagia is common following a stroke which necessitates feeding via a nasogastric tube. Nasogastric tubes are not well tolerated by stroke patients and may be frequently dislodged. Hence, interventions such as tape, the nasal bridle/loop or hand mittens may be used to maintain nasogastric tube position. However, evidence around the effectiveness and acceptability of these interventions has not been reviewed and synthesised. Integrative literature review. Database searches in MEDLINE, PubMed, CINAHL, Scopus, Cochrane and EMBASE; manual reference list searches. Seven studies met the eligibility criteria and were included in the review. Evidence for the effectiveness of nasal bridle/loop and hand mittens to maintain nasogastric tube position in patients after a stroke is spare and methodologically poor, and especially limited around hand mittens use. There is insufficient evidence about the acceptability of both nasal bridle/loop and hand mittens among stroke patients. Current clinical practice is underpinned by assumptions around the acceptability of nasal bridle/loop and hand mittens to secure nasogastric tubes. This results in reliance on consensual judgement between professional, patients and their families to guide their use among individuals with dysphagia after stroke. Further research is required to assess the effectiveness of hand mittens and acceptability of both nasal bridle/loop and hand mittens among stroke patients to inform guideline development. Given the lack of evidence on the acceptability of hand mittens and nasal bridle/loop among stroke patients to inform evidence-based guidelines and protocols, healthcare professionals should reach consensus on their use by exercising clinical

An Architectural Style for Closed-loop Process-Control

DEFF Research Database (Denmark)

Christensen, Henrik Bærbak; Eriksen, Ole

2003-01-01

This report describes an architectural style for distributed closed-loop process control systems with high performance and hard real-time constraints. The style strikes a good balance between the architectural qualities of performance and modifiability/maintainability that traditionally are often...

An Architectural Style for Closed-loop Process-Control

DEFF Research Database (Denmark)

Christensen, Henrik Bærbak

This report describes an architectural style for distributed closed-loop process control systems with high performance and hard real-time constraints. The style strikes a good balance between the architectural qualities of performance and modifiability/maintainability that traditionally are often...

Semiclassical relations and IR effects in de Sitter and slow-roll space-times

Energy Technology Data Exchange (ETDEWEB)

Giddings, Steven B. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Sloth, Martin S., E-mail: giddings@physics.ucsb.edu, E-mail: sloth@cern.ch [CERN, Physics Department, Theory Unit, CH-1211 Geneva 23 (Switzerland)

2011-01-01

We calculate IR divergent graviton one-loop corrections to scalar correlators in de Sitter space, and show that the leading IR contribution may be reproduced via simple semiclassical consistency relations. One can likewise use such semiclassical relations to calculate leading IR corrections to correlators in slow-roll inflation. The regulated corrections shift the tensor/scalar ratio and consistency relation of single field inflation, and non-gaussianity parameters averaged over very large distances. For inflation of sufficient duration, for example arising from a chaotic inflationary scenario, these corrections become of order unity. First-order corrections of this size indicate a breakdown of the perturbative expansion, and suggest the need for a non-perturbative description of the corresponding regime. This is analogous to a situation argued to arise in black hole evolution, and to interfere with a sharp perturbative calculation of ''missing information'' in Hawking radiation.

Semiclassical relations and IR effects in de Sitter and slow-roll space-times

International Nuclear Information System (INIS)

Giddings, Steven B.; Sloth, Martin S.

2011-01-01

We calculate IR divergent graviton one-loop corrections to scalar correlators in de Sitter space, and show that the leading IR contribution may be reproduced via simple semiclassical consistency relations. One can likewise use such semiclassical relations to calculate leading IR corrections to correlators in slow-roll inflation. The regulated corrections shift the tensor/scalar ratio and consistency relation of single field inflation, and non-gaussianity parameters averaged over very large distances. For inflation of sufficient duration, for example arising from a chaotic inflationary scenario, these corrections become of order unity. First-order corrections of this size indicate a breakdown of the perturbative expansion, and suggest the need for a non-perturbative description of the corresponding regime. This is analogous to a situation argued to arise in black hole evolution, and to interfere with a sharp perturbative calculation of ''missing information'' in Hawking radiation

String corrections to circular Wilson loop and anomalies

Science.gov (United States)

Cagnazzo, Alessandra; Medina-Rincon, Daniel; Zarembo, Konstantin

2018-02-01

We study string quantum corrections to the ratio of latitude and circular Wilson loops in N = 4 super-Yang-Mills theory at strong coupling. Conformal gauge for the corresponding minimal surface in AdS5 × S 5 is singular and we show that an IR anomaly associated with the divergence in the conformal factor removes previously reported discrepancy with the exact field-theory result. We also carefully check conformal anomaly cancellation and recalculate fluctuation determinants by directly evaluting phaseshifts for all the fluctuation modes.

Supersymmetric Regularization Two-Loop QCD Amplitudes and Coupling Shifts

Energy Technology Data Exchange (ETDEWEB)

Dixon, Lance

2002-03-08

We present a definition of the four-dimensional helicity (FDH) regularization scheme valid for two or more loops. This scheme was previously defined and utilized at one loop. It amounts to a variation on the standard 't Hooft-Veltman scheme and is designed to be compatible with the use of helicity states for ''observed'' particles. It is similar to dimensional reduction in that it maintains an equal number of bosonic and fermionic states, as required for preserving supersymmetry. Supersymmetry Ward identities relate different helicity amplitudes in supersymmetric theories. As a check that the FDH scheme preserves supersymmetry, at least through two loops, we explicitly verify a number of these identities for gluon-gluon scattering (gg {yields} gg) in supersymmetric QCD. These results also cross-check recent non-trivial two-loop calculations in ordinary QCD. Finally, we compute the two-loop shift between the FDH coupling and the standard {bar M}{bar S} coupling, {alpha}{sub s}. The FDH shift is identical to the one for dimensional reduction. The two-loop coupling shifts are then used to obtain the three-loop QCD {beta} function in the FDH and dimensional reduction schemes.

Supersymmetric Regularization Two-Loop QCD Amplitudes and Coupling Shifts

International Nuclear Information System (INIS)

Dixon, Lance

2002-01-01

We present a definition of the four-dimensional helicity (FDH) regularization scheme valid for two or more loops. This scheme was previously defined and utilized at one loop. It amounts to a variation on the standard 't Hooft-Veltman scheme and is designed to be compatible with the use of helicity states for ''observed'' particles. It is similar to dimensional reduction in that it maintains an equal number of bosonic and fermionic states, as required for preserving supersymmetry. Supersymmetry Ward identities relate different helicity amplitudes in supersymmetric theories. As a check that the FDH scheme preserves supersymmetry, at least through two loops, we explicitly verify a number of these identities for gluon-gluon scattering (gg → gg) in supersymmetric QCD. These results also cross-check recent non-trivial two-loop calculations in ordinary QCD. Finally, we compute the two-loop shift between the FDH coupling and the standard MS coupling, α s . The FDH shift is identical to the one for dimensional reduction. The two-loop coupling shifts are then used to obtain the three-loop QCD β function in the FDH and dimensional reduction schemes

Non-supersymmetric Wilson loop in N = 4 SYM and defect 1d CFT

Science.gov (United States)

Beccaria, Matteo; Giombi, Simone; Tseytlin, Arkady A.

2018-03-01

Following Polchinski and Sully (arXiv:1104.5077), we consider a generalized Wilson loop operator containing a constant parameter ζ in front of the scalar coupling term, so that ζ = 0 corresponds to the standard Wilson loop, while ζ = 1 to the locally supersymmetric one. We compute the expectation value of this operator for circular loop as a function of ζ to second order in the planar weak coupling expansion in N = 4 SYM theory. We then explain the relation of the expansion near the two conformal points ζ = 0 and ζ = 1 to the correlators of scalar operators inserted on the loop. We also discuss the AdS5 × S 5 string 1-loop correction to the strong-coupling expansion of the standard circular Wilson loop, as well as its generalization to the case of mixed boundary conditions on the five-sphere coordinates, corresponding to general ζ. From the point of view of the defect CFT1 defined on the Wilson line, the ζ-dependent term can be seen as a perturbation driving a RG flow from the standard Wilson loop in the UV to the supersymmetric Wilson loop in the IR. Both at weak and strong coupling we find that the logarithm of the expectation value of the standard Wilson loop for the circular contour is larger than that of the supersymmetric one, which appears to be in agreement with the 1d analog of the F-theorem.

Closed loop two-echelon repairable item systems

NARCIS (Netherlands)

Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.

In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

Closed-loop two-echelon repairable item systems

NARCIS (Netherlands)

Spanjers, L.; Zijm, Willem H.M.; van Ommeren, Jan C.W.

2003-01-01

In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

Closed loop two-echelon repairable item systems

NARCIS (Netherlands)

Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.; Liberopoulos, G.; Papadopoulos, C.T.; Tan, B.; MacGregor Smith, J.; Gershwin, S.B.

2006-01-01

In this paper we consider closed loop two-echelon epairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

LoopIng: a template-based tool for predicting the structure of protein loops.

KAUST Repository

Messih, Mario Abdel

2015-08-06

Predicting the structure of protein loops is very challenging, mainly because they are not necessarily subject to strong evolutionary pressure. This implies that, unlike the rest of the protein, standard homology modeling techniques are not very effective in modeling their structure. However, loops are often involved in protein function, hence inferring their structure is important for predicting protein structure as well as function.We describe a method, LoopIng, based on the Random Forest automated learning technique, which, given a target loop, selects a structural template for it from a database of loop candidates. Compared to the most recently available methods, LoopIng is able to achieve similar accuracy for short loops (4-10 residues) and significant enhancements for long loops (11-20 residues). The quality of the predictions is robust to errors that unavoidably affect the stem regions when these are modeled. The method returns a confidence score for the predicted template loops and has the advantage of being very fast (on average: 1 min/loop).www.biocomputing.it/loopinganna.tramontano@uniroma1.itSupplementary data are available at Bioinformatics online.

Package-X 2.0: A Mathematica package for the analytic calculation of one-loop integrals

Science.gov (United States)

Patel, Hiren H.

2017-09-01

This article summarizes new features and enhancements of the first major update of Package-X. Package-X 2.0 can now generate analytic expressions for arbitrarily high rank dimensionally regulated tensor integrals with up to four distinct propagators, each with arbitrary integer weight, near an arbitrary even number of spacetime dimensions, giving UV divergent, IR divergent, and finite parts at (almost) any real-valued kinematic point. Additionally, it can generate multivariable Taylor series expansions of these integrals around any non-singular kinematic point to arbitrary order. All special functions and abbreviations output by Package-X 2.0 support Mathematica's arbitrary precision evaluation capabilities to deal with issues of numerical stability. Finally, tensor algebraic routines of Package-X have been polished and extended to support open fermion chains both on and off shell. The documentation (equivalent to over 100 printed pages) is accessed through Mathematica's Wolfram Documentation Center and contains information on all Package-X symbols, with over 300 basic usage examples, 3 project-scale tutorials, and instructions on linking to FEYNCALC and LOOPTOOLS. Program files doi:http://dx.doi.org/10.17632/yfkwrd4d5t.1 Licensing provisions: CC by 4.0 Programming language: Mathematica (Wolfram Language) Journal reference of previous version: H. H. Patel, Comput. Phys. Commun 197, 276 (2015) Does the new version supersede the previous version?: Yes Summary of revisions: Extension to four point one-loop integrals with higher powers of denominator factors, separate extraction of UV and IR divergent parts, testing for power IR divergences, construction of Taylor series expansions of one-loop integrals, numerical evaluation with arbitrary precision arithmetic, manipulation of fermion chains, improved tensor algebraic routines, and much expanded documentation. Nature of problem: Analytic calculation of one-loop integrals in relativistic quantum field theory. Solution

Scheme-Independent Calculation of $γ_{\\barψψ,IR}$ for an SU(3) Gauge Theory

DEFF Research Database (Denmark)

Ryttov, Thomas A.; Shrock, Robert

2016-01-01

We present a scheme-independent calculation of the infrared value of the anomalous dimension of the fermion bilinear, $\\gamma_{\\bar\\psi\\psi,IR}$ in an SU(3) gauge theory as a function of the number of fermions, $N_f$, via a series expansion in powers of $\\Delta_f$, where $\\Delta_f=(16.5-N......_f)$, to order $\\Delta_f^4$. We perform an extrapolation to obtain the first determination of the exact $\\gamma_{\\bar\\psi\\psi,IR}$ from continuum field theory. The results are compared with calculations of the $n$-loop values of this anomalous dimension from series in powers of the coupling and from lattice...

UNRAVELLING THE COMPONENTS OF A MULTI-THERMAL CORONAL LOOP USING MAGNETOHYDRODYNAMIC SEISMOLOGY

Energy Technology Data Exchange (ETDEWEB)

Prasad, S. Krishna; Jess, D. B. [Astrophysics Research Centre, School of Mathematics and Physics, Queen’s University Belfast, Belfast, BT7 1NN (United Kingdom); Klimchuk, J. A. [Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD, 20771 (United States); Banerjee, D., E-mail: krishna.prasad@qub.ac.uk [Indian Institute of Astrophysics, II Block Koramangala, Bengaluru 560034 (India)

2017-01-10

Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite significant advances in observations and theory, our knowledge on the fundamental properties of these structures is limited. Here, we present unprecedented observations of accelerating slow magnetoacoustic waves along a coronal loop that show differential propagation speeds in two distinct temperature channels, revealing the multi-stranded and multithermal nature of the loop. Utilizing the observed speeds and employing nonlinear force-free magnetic field extrapolations, we derive the actual temperature variation along the loop in both channels, and thus are able to resolve two individual components of the multithermal loop for the first time. The obtained positive temperature gradients indicate uniform heating along the loop, rather than isolated footpoint heating.

Alkoholio ir tabako pasiūlos ir paklausos teisinio reguliavimo raida Lietuvos Respublikoje: problemos ir sprendimai

OpenAIRE

Mockevičius, Arminas

2014-01-01

Viešosios teisės magistro studijų programos studento Armino Mockevičiaus buvo parašytas magistro baigiamasis darbas „Alkoholio ir tabako pasiūlos ir paklausos teisinio reguliavimo raida Lietuvos Respublikoje: problemos ir sprendimai“. Šis darbas parašytas Vilniuje, 2014 metais, Mykolo Romerio universiteto Teisės fakulteto Konstitucinės ir administracinės teisės institute, vadovaujant dr. Gintautui Vilkeliui, apimtis 98 p. Darbo tikslas yra atskleisti alkoholio ir tabako pasiūlos ir paklau...

Twisted Poincare invariance, noncommutative gauge theories and UV-IR mixing

Energy Technology Data Exchange (ETDEWEB)

Balachandran, A.P. [Department of Physics, Syracuse University, Syracuse NY, 13244-1130 (United States)], E-mail: bal@physics.syr.edu; Pinzul, A. [Insituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil)], E-mail: apinzul@fma.if.usp.br; Queiroz, A.R. [Centro Internacional de Fisica da Materia Condensada, Universidade de Brasilia, C.P. 04667, Brasilia, DF (Brazil); Universidade Federal de Goias, Campus Avancado de Catalao, Departamento de Fisica, St. Universitario - 75700-000, Catalao-GO (Brazil)], E-mail: amilcarq@gmail.com

2008-10-09

In the absence of gauge fields, quantum field theories on the Groenewold-Moyal (GM) plane are invariant under a twisted action of the Poincare group if they are formulated following [M. Chaichian, P.P. Kulish, K. Nishijima, A. Tureanu, Phys. Lett. B 604 (2004) 98, (hep-th/0408069); P. Aschieri, C. Blohmann, M. Dimitrijevic, F. Meyer, P. Schupp, J. Wess, Class. Quantum Grav. 22 (2005) 3511, (hep-th/0504183); A.P. Balachandran, A. Pinzul, B.A. Qureshi, S. Vaidya, (hep-th/0608138); A.P. Balachandran, A. Pinzul, B.A. Qureshi, S. Vaidya, (arXiv: 0708.0069 [hep-th]); A.P. Balachandran, A. Pinzul, B.A. Qureshi, S. Vaidya, (arXiv: 0708.1379 [hep-th]); A.P. Balachandran, A. Pinzul, B.A. Qureshi, (arXiv: 0708.1779 [hep-th])]. In that formulation, such theories also have no UV-IR mixing [A.P. Balachandran, A. Pinzul, B.A. Qureshi, Phys. Lett. B 634 (2006) 434, (hep-th/0508151)]. Here we investigate UV-IR mixing in gauge theories with matter following the approach of [A.P. Balachandran, A. Pinzul, B. A. Qureshi, S. Vaidya, (hep-th/0608138); A.P. Balachandran, A. Pinzul, B.A. Qureshi, S. Vaidya, (arXiv: 0708.0069 [hep-th])]. We prove that there is UV-IR mixing in the one-loop diagram of the S-matrix involving a coupling between gauge and matter fields on the GM plane, the gauge field being non-Abelian. There is no UV-IR mixing if it is Abelian.

Loop Transfer Matrix and Loop Quantum Mechanics

International Nuclear Information System (INIS)

Savvidy, George K.

2000-01-01

The gonihedric model of random surfaces on a 3d Euclidean lattice has equivalent representation in terms of transfer matrix K(Q i ,Q f ), which describes the propagation of loops Q. We extend the previous construction of the loop transfer matrix to the case of nonzero self-intersection coupling constant κ. We introduce the loop generalization of Fourier transformation which allows to diagonalize transfer matrices, that depend on symmetric difference of loops only and express all eigenvalues of 3d loop transfer matrix through the correlation functions of the corresponding 2d statistical system. The loop Fourier transformation allows to carry out the analogy with quantum mechanics of point particles, to introduce conjugate loop momentum P and to define loop quantum mechanics. We also consider transfer matrix on 4d lattice which describes propagation of memebranes. This transfer matrix can also be diagonalized by using the generalized Fourier transformation, and all its eigenvalues are equal to the correlation functions of the corresponding 3d statistical system. In particular the free energy of the 4d membrane system is equal to the free energy of 3d gonihedric system of loops and is equal to the free energy of 2d Ising model. (author)

A role for myelin-associated peroxisomes in maintaining paranodal loops and axonal integrity.

Science.gov (United States)

Kassmann, Celia M; Quintes, Susanne; Rietdorf, Jens; Möbius, Wiebke; Sereda, Michael Werner; Nientiedt, Tobias; Saher, Gesine; Baes, Myriam; Nave, Klaus-Armin

2011-07-21

Demyelinating diseases of the nervous system cause axon loss but the underlying mechanisms are not well understood. Here we show by confocal and electron microscopy that in myelin-forming glia peroxisomes are associated with myelin membranes. When peroxisome biogenesis is experimentally perturbed in Pex5 conditional mouse mutants, myelination by Schwann cells appears initially normal. However, in nerves of older mice paranodal loops become physically unstable and develop swellings filled with vesicles and electron-dense material. This novel model of a demyelinating neuropathy demonstrates that peroxisomes serve an important function in the peripheral myelin compartment, required for long-term axonal integrity. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

TRF2 Recruits RTEL1 to Telomeres in S Phase to Promote T-Loop Unwinding

OpenAIRE

Sarek, Grzegorz; Vannier, Jean-Baptiste; Panier, Stephanie; Petrini, John?H.J.; Boulton, Simon?J.

2015-01-01

Summary The helicase RTEL1 promotes t-loop unwinding and suppresses telomere fragility to maintain the integrity of vertebrate telomeres. An interaction between RTEL1 and PCNA is important to prevent telomere fragility, but how RTEL1 engages with the telomere to promote t-loop unwinding is unclear. Here, we establish that the shelterin protein TRF2 recruits RTEL1 to telomeres in S phase, which is required to?prevent catastrophic t-loop processing by structure-specific nucleases. We show that ...

Osteoclasts and CD8 T cells form a negative feedback loop that contributes to homeostasis of both the skeletal and immune systems.

Science.gov (United States)

Buchwald, Zachary S; Aurora, Rajeev

2013-01-01

There are a number of dynamic regulatory loops that maintain homeostasis of the immune and skeletal systems. In this review, we highlight a number of these regulatory interactions that contribute to maintaining homeostasis. In addition, we review data on a negative regulatory feedback loop between osteoclasts and CD8 T cells that contributes to homeostasis of both the skeletal and immune systems.

Loop kinematics

International Nuclear Information System (INIS)

Migdal, A.A.

1982-01-01

Basic operators acting in the loop space are introduced. The topology of this space and properties of the Stokes type loop functionals are discussed. The parametrically invariant loop calculus developed here is used in the loop dynamics

Traceable calibration of hospital 192Ir HDR sources

International Nuclear Information System (INIS)

Govinda Rajan, K.N.; Sharma, S.D.; Palaniselvam, T.; Vandana, S.; Bhatt, B.C.; Vinatha, S.; Patki, V.S.; Pendse, A.M.; Kannan, V.

2004-01-01

A HDR 1000 PLUS well type ionization chamber, procured from Standard Imaging, USA, and maintained by medical Physics and Safety Section (MPSS), Bhabha Atomic Research Centre (BARC), India, as a reference well chamber 1 (RWCH1), was traceably calibrated against the primary standard established by Radiological Standards Laboratory (RSL), BARC for 192 Ir HDR source, in terms of air kerma strength (AKS). An indigenously developed well-type ionization chamber, reference well chamber 2 (RWCH2) and electrometer system, fabricated by CD High Tech (CDHT) Instruments Private Ltd., Bangalore, India, was in turn calibrated against RWCH1. The CDHT system (i.e. RWCH2 and CDHT electrometer system) was taken to several hospitals, in different regions of the country, to check the calibration status of 192 Ir HDR sources. The result of this calibration audit work is reported here. (author)

Guidelines on the use of space maintainers following premature loss of primary teeth.

Science.gov (United States)

Brothwell, D J

1997-11-01

To formulate evidence-based guidelines on the appropriate use of space maintaining appliances to prevent or reduce the severity of malocclusion in the permanent dentition following the premature loss of primary teeth. Placement of lingual arch, palatal arch, band-loop, crown-loop, and intra-alveolar space maintainers. Reduced prevalence or severity of space loss in the primary or mixed dentition, reduced prevalence or severity of malocclusion in the permanent dentition measured as significant changes in: crowding, ectopic eruption, impacted teeth, Angle's class II or III occlusion, crossbite, deep overbite, deep overjet, or midline shift. Articles published from 1966 to 1996, located though Medline searches. Only clinical trials, cohort studies, case-control studies, or large case series were considered. Relevant clinical findings were evaluated and categorized using evidence-based methods and values established by the Canadian Task Force on the Periodic Health Examination. A recommendation was developed for the use of space maintainers. The potential benefits of using space maintaining appliances include reduced prevalence or severity of: crowding, ectopic eruption, tooth impaction, crossbite, excessive overbite and overjet, and poor molar relationship. Other advantages include the potential for considerable cost savings by reducing the need for future orthodontic treatment. The potential disadvantages of using space maintaining appliances include soft tissue impingement, interference with eruption of adjacent teeth, pain, plaque accumulation, caries, and broken, dislodged or lost appliances. There is poor evidence to recommend for or against the use of space maintainers to prevent or reduce the severity of malocclusion in the permanent dentition (see Table 1, Recommendation C) Decisions regarding the use of space maintainers must therefore be guided by factors other than scientific evidence.

The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues; Das TApIR Experiment IR-Absorptionsspektren fluessiger Wasserstoffisotopologe

Energy Technology Data Exchange (ETDEWEB)

Groessle, Robin

2015-11-27

The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

Tarptautinio turizmo raida ir vystymo prognozės Lietuvoje ir Lenkijoje

OpenAIRE

Veličkaitė, Dalia

2009-01-01

Išanalizuota ir įvertinta Lietuvos ir Lenkijos atvykstamojo turizmo raida 2000- 2007m., užsienio turistų srautai, apgyvendinimo paslaugų paklausa, turistų tikslai ir kelionių transporto pasirinkimas, turistų išlaidos ir šalių turizmo pajamos, iškeltos atvykstamojo turizmo problemos bei pateikti jų sprendimo siūlymai.paskutinėje darbo dalyje buvo atliktos 2008- 2015metų Lietuvos ir Lenkijos turizmo raidos prognozės. In the final master work Lithuanian and Poland arriving tourism development...

A Triple-Loop Inductive Power Transmission System for Biomedical Applications.

Science.gov (United States)

Lee, Byunghun; Kiani, Mehdi; Ghovanloo, Maysam

2016-02-01

A triple-loop wireless power transmission (WPT) system equipped with closed-loop global power control, adaptive transmitter (Tx) resonance compensation (TRC), and automatic receiver (Rx) resonance tuning (ART) is presented. This system not only opposes coupling and load variations but also compensates for changes in the environment surrounding the inductive link to enhance power transfer efficiency (PTE) in applications such as implantable medical devices (IMDs). The Tx was built around a commercial off-the-shelf (COTS) radio-frequency identification (RFID) reader, operating at 13.56 MHz. A local Tx loop finds the optimal capacitance in parallel with the Tx coil by adjusting a varactor. A global power control loop maintains the received power at a desired level in the presence of changes in coupling distance, coil misalignments, and loading. Moreover, a local Rx loop is implemented inside a power management integrated circuit (PMIC) to avoid PTE degradation due to the Rx coil surrounding environment and process variations. The PMIC was fabricated in a 0.35- μm 4M2P standard CMOS process with 2.54 mm(2) active area. Measurement results show that the proposed triple-loop system improves the overall PTE by up to 10.5% and 4.7% compared to a similar open- and single closed-loop system, respectively, at nominal coil distance of 2 cm. The added TRC and ART loops contribute 2.3% and 1.4% to the overall PTE of 13.5%, respectively. This is the first WPT system to include three loops to dynamically compensate for environment and circuit variations and improve the overall power efficiency all the way from the driver output in Tx to the load in Rx.

Electronic structure, local magnetism, and spin-orbit effects of Ir(IV)-, Ir(V)-, and Ir(VI)-based compounds

Energy Technology Data Exchange (ETDEWEB)

Laguna-Marco, M. A.; Kayser, P.; Alonso, J. A.; Martínez-Lope, M. J.; van Veenendaal, M.; Choi, Y.; Haskel, D.

2015-06-01

Element- and orbital-selective x-ray absorption and magnetic circular dichroism measurements are carried out to probe the electronic structure and magnetism of Ir 5d electronic states in double perovskite Sr2MIrO6 (M = Mg, Ca, Sc, Ti, Ni, Fe, Zn, In) and La2NiIrO6 compounds. All the studied systems present a significant influence of spin-orbit interactions in the electronic ground state. In addition, we find that the Ir 5d local magnetic moment shows different character depending on the oxidation state despite the net magnetization being similar for all the compounds. Ir carries an orbital contribution comparable to the spin contribution for Ir4+ (5d(5)) and Ir5+ (5d(4)) oxides, whereas the orbital contribution is quenched for Ir6+ (5d(3)) samples. Incorporation of a magnetic 3d atom allows getting insight into the magnetic coupling between 5d and 3d transition metals. Together with previous susceptibility and neutron diffractionmeasurements, the results indicate that Ir carries a significant local magnetic moment even in samples without a 3d metal. The size of the (small) net magnetization of these compounds is a result of predominant antiferromagnetic interactions between local moments coupled with structural details of each perovskite structure

IR-IR Conformation Specific Spectroscopy of Na+(Glucose) Adducts

Science.gov (United States)

Voss, Jonathan M.; Kregel, Steven J.; Fischer, Kaitlyn C.; Garand, Etienne

2018-01-01

We report an IR-IR double resonance study of the structural landscape present in the Na+(glucose) complex. Our experimental approach involves minimal modifications to a typical IR predissociation setup, and can be carried out via ion-dip or isomer-burning methods, providing additional flexibility to suit different experimental needs. In the current study, the single-laser IR predissociation spectrum of Na+(glucose), which clearly indicates contributions from multiple structures, was experimentally disentangled to reveal the presence of three α-conformers and five β-conformers. Comparisons with calculations show that these eight conformations correspond to the lowest energy gas-phase structures with distinctive Na+ coordination. [Figure not available: see fulltext.

PKCδ-mediated IRS-1 Ser24 phosphorylation negatively regulates IRS-1 function

International Nuclear Information System (INIS)

Greene, Michael W.; Ruhoff, Mary S.; Roth, Richard A.; Kim, Jeong-a; Quon, Michael J.; Krause, Jean A.

2006-01-01

The IRS-1 PH and PTB domains are essential for insulin-stimulated IRS-1 Tyr phosphorylation and insulin signaling, while Ser/Thr phosphorylation of IRS-1 disrupts these signaling events. To investigate consensus PKC phosphorylation sites in the PH-PTB domains of human IRS-1, we changed Ser24, Ser58, and Thr191 to Ala (3A) or Glu (3E), to block or mimic phosphorylation, respectively. The 3A mutant abrogated the inhibitory effect of PKCδ on insulin-stimulated IRS-1 Tyr phosphorylation, while reductions in insulin-stimulated IRS-1 Tyr phosphorylation, cellular proliferation, and Akt activation were observed with the 3E mutant. When single Glu mutants were tested, the Ser24 to Glu mutant had the greatest inhibitory effect on insulin-stimulated IRS-1 Tyr phosphorylation. PKCδ-mediated IRS-1 Ser24 phosphorylation was confirmed in cells with PKCδ catalytic domain mutants and by an RNAi method. Mechanistic studies revealed that IRS-1 with Ala and Glu point mutations at Ser24 impaired phosphatidylinositol-4,5-bisphosphate binding. In summary, our data are consistent with the hypothesis that Ser24 is a negative regulatory phosphorylation site in IRS-1

Two-loop polygon Wilson loops in N = 4 SYM

International Nuclear Information System (INIS)

Anastasiou, C.; Brandhuber, A.; Heslop, P.; Spence, B.; Travaglini, G.; Khoze, V.V.

2009-01-01

We compute for the first time the two-loop corrections to arbitrary n-gon lightlike Wilson loops in N = 4 supersymmetric Yang-Mills theory, using efficient numerical methods. The calculation is motivated by the remarkable agreement between the finite part of planar six-point MHV amplitudes and hexagon Wilson loops which has been observed at two loops. At n = 6 we confirm that the ABDK/BDS ansatz must be corrected by adding a remainder function, which depends only on conformally invariant ratios of kinematic variables. We numerically compute remainder functions for n = 7,8 and verify dual conformal invariance. Furthermore, we study simple and multiple collinear limits of the Wilson loop remainder functions and demonstrate that they have precisely the form required by the collinear factorisation of the corresponding two-loop n-point amplitudes. The number of distinct diagram topologies contributing to the n-gon Wilson loops does not increase with n, and there is a fixed number of 'master integrals', which we have computed. Thus we have essentially computed general polygon Wilson loops, and if the correspondence with amplitudes continues to hold, all planar n-point two-loop MHV amplitudes in the N = 4 theory.

Prevalence of dependent loops in urinary drainage systems in hospitalized patients.

Science.gov (United States)

Danek, Gale; Gravenstein, Nikolaus; Lizdas, David E; Lampotang, Samsun

2015-01-01

The purpose of this study was to measure the prevalence and configuration of dependent loops in urinary drainage systems in hospitalized, catheterized adults. The study sample comprised 141 patients with indwelling urinary catheters; subjects were hospitalized at an academic health center in northern Florida. We measured the prevalence of dependent loops in urine drainage systems and the incidence of urine-filled dependent loops over a 3-week period. We measured the heights of the crest (H(c)), trough (H(t)), and, when urine-filled dependent loops were present, the patient-side (H(p)) and bag-side (H(b)) menisci with a laser measurement system. All variables were measured in centimeters. The majority of observed urine drainage systems (85%) contained dependent loops in the drainage tubing and 93.8% of the dependent loops contained urine. H(c) and H(t) averaged 45.1 ± 11.1 and 27 ± 16.7 cm, respectively. Meniscus height difference (H(b) - H(p)) averaged 8.2 ± 5.8 and -12.2 ± 9.9 cm when H(p) H(b) (32.7%), respectively. We found that dependent loops are extremely common in urinary drainage systems among hospitalized patients despite the manufacturer recommendations and nursing and hospital policies. Maintaining the urine drainage tubing free of dependent loops would require incorporation into nursing care priorities and workflow as inadvertent force on the tubing, for example, patient movement or nurse contact can change tubing configuration and allow excess drainage tubing to re-form a dependent loop.

Development of Start-up and Shutdown Procedure for the HANARO Fuel Test Loop

International Nuclear Information System (INIS)

Park, S. K.; Sim, B. S.; Chi, D. Y.; Lee, J. M.; Lee, C. Y.; Ahn, S. H.

2009-06-01

A start-up and shutdown procedure for the HANARO fuel test loop has been developed. This is a facility for fuel and material irradiation tests. The facility provides experimental conditions similar to the normal operational pressures and temperatures of commercial PWR and CANDU plants. The normal operation modes of the HANARO fuel test loop are classified into loop shutdown, cold stand-by 1, cold stand-by 2, hot stand-by, and hot operation. The operation modes depend on the fission power of test fuels and the coolant temperature at the inlet of the in-pile test section. The HANARO must maintain a shutdown mode if the HANARO fuel test loop is loop shutdown, cold stand-by 1, cold stand-by 2, or hot stand-by. As the HANARO becomes power operation mode, the operation mode of the HANARO fuel test loop comes to hot operation from hot stand-by. The procedure for the HANARO fuel test loop consists of four main parts such as check of initial conditions, stat-up operation procedure, shutdown operation procedure, and check lists for operations. Several hot test operations ensure that the procedure is appropriate

Application of CAD-CAM for Fabrication of Metal-Free Band and Loop Space Maintainer.

Science.gov (United States)

Soni, Harleen Kaur

2017-02-01

An ideal occlusion with proper tooth alignment and fully functional teeth is the ultimate goal of all dental treatments. Premature extraction of deciduous teeth is a common sequeale of untreated dental caries in teeth in which the damage is far beyond repair. Premature extraction might lead to loss of space for the successor tooth, drifting of teeth and loss of arch integrity leading to malocclusion in the permanent teeth. To prevent the space loss, space maintainers are designed and delivered at the time of extraction to allow for development of proper functional occlusion in children till the eruption of the succedaneous permanent tooth. A six-year-old female patient with chronic intra-radicular abscess in upper right first primary molar was treated with extraction followed by the placement of BruxZir zirconia space maintainer. Clinical and radiographic examinations were performed at one and six months. At the end of six months, the patient was completely asymptomatic and there were no visible signs of gingival inflammation and tissue irritation at the site of the space maintainer.

The efficacy of imagery rescripting (IR) for social phobia: a randomized controlled trial.

Science.gov (United States)

Lee, Seung Won; Kwon, Jung-Hye

2013-12-01

There is a need for brief effective treatment of social phobia and Imagery Rescripting (IR) is a potential candidate. The purpose of this study was to examine the efficacy of IR preceded by cognitive restructuring as a stand-alone brief treatment using a randomized controlled design. Twenty-three individuals with social phobia were randomly assigned to an IR group or to a control group. Participants in the IR group were provided with one session of imagery interviewing and two sessions of cognitive restructuring and Imagery Rescripting. Those in the control group had one session of clinical interviewing and two sessions of supportive therapy. Outcome measures including the Korean version of the social avoidance and distress scale (K-SADS) were administered before and after treatment, and at three-month follow-up. The short version of the Questionnaire upon Mental Imagery and the Traumatic Experience Scale were also administered before treatment. Participants in the IR group improved significantly on K-SADS and other outcome measures, compared to the control group. The beneficial effects of IR were maintained at three-month follow-up. It was also found that mental imagery ability and the severity of the traumatic experience did not moderate the outcome of IR. Further studies are needed to replicate the findings of our study using a large sample. The efficacy of IR as a stand-alone brief treatment was demonstrated for social phobia. The findings indicate that IR could be utilized as a cost-effective intervention for social phobia. Copyright © 2013 Elsevier Ltd. All rights reserved.

Alternative loop rings

CERN Document Server

Goodaire, EG; Polcino Milies, C

1996-01-01

For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

Role of the antiferromagnetic pinning layer on spin wave properties in IrMn/NiFe based spin-valves

Energy Technology Data Exchange (ETDEWEB)

Gubbiotti, G., E-mail: gubbiotti@fisica.unipg.it; Tacchi, S. [Istituto Officina dei Materiali del CNR (IOM-CNR), Unità di Perugia, I-06123 Perugia (Italy); Del Bianco, L. [Department of Physics and Astronomy, University of Bologna, I-40127 Bologna (Italy); Department of Physics and Earth Sciences and CNISM, University of Ferrara, I-44122 Ferrara (Italy); Bonfiglioli, E.; Giovannini, L.; Spizzo, F.; Zivieri, R. [Department of Physics and Earth Sciences and CNISM, University of Ferrara, I-44122 Ferrara (Italy); Tamisari, M. [Department of Physics and Earth Sciences and CNISM, University of Ferrara, I-44122 Ferrara (Italy); Dipartimento di Fisica e Geologia, Università di Perugia, I-06123 Perugia (Italy)

2015-05-07

Brillouin light scattering (BLS) was exploited to study the spin wave properties of spin-valve (SV) type samples basically consisting of two 5 nm-thick NiFe layers (separated by a Cu spacer of 5 nm), differently biased through the interface exchange coupling with an antiferromagnetic IrMn layer. Three samples were investigated: a reference SV sample, without IrMn (reference); one sample with an IrMn underlayer (10 nm thick) coupled to the bottom NiFe film; one sample with IrMn underlayer and overlayer of different thickness (10 nm and 6 nm), coupled to the bottom and top NiFe film, respectively. The exchange coupling with the IrMn, causing the insurgence of the exchange bias effect, allowed the relative orientation of the NiFe magnetization vectors to be controlled by an external magnetic field, as assessed through hysteresis loop measurements by magneto-optic magnetometry. Thus, BLS spectra were acquired by sweeping the magnetic field so as to encompass both the parallel and antiparallel alignment of the NiFe layers. The BLS results, well reproduced by the presented theoretical model, clearly revealed the combined effects on the spin dynamic properties of the dipolar interaction between the two NiFe films and of the interface IrMn/NiFe exchange coupling.

Random walk loop soups and conformal loop ensembles

NARCIS (Netherlands)

van de Brug, T.; Camia, F.; Lis, M.

2016-01-01

The random walk loop soup is a Poissonian ensemble of lattice loops; it has been extensively studied because of its connections to the discrete Gaussian free field, but was originally introduced by Lawler and Trujillo Ferreras as a discrete version of the Brownian loop soup of Lawler and Werner, a

Renormalization of loop functions for all loops

International Nuclear Information System (INIS)

Brandt, R.A.; Neri, F.; Sato, M.

1981-01-01

It is shown that the vacuum expectation values W(C 1 ,xxx, C/sub n/) of products of the traces of the path-ordered phase factors P exp[igcontour-integral/sub C/iA/sub μ/(x)dx/sup μ/] are multiplicatively renormalizable in all orders of perturbation theory. Here A/sub μ/(x) are the vector gauge field matrices in the non-Abelian gauge theory with gauge group U(N) or SU(N), and C/sub i/ are loops (closed paths). When the loops are smooth (i.e., differentiable) and simple (i.e., non-self-intersecting), it has been shown that the generally divergent loop functions W become finite functions W when expressed in terms of the renormalized coupling constant and multiplied by the factors e/sup -K/L(C/sub i/), where K is linearly divergent and L(C/sub i/) is the length of C/sub i/. It is proved here that the loop functions remain multiplicatively renormalizable even if the curves have any finite number of cusps (points of nondifferentiability) or cross points (points of self-intersection). If C/sub γ/ is a loop which is smooth and simple except for a single cusp of angle γ, then W/sub R/(C/sub γ/) = Z(γ)W(C/sub γ/) is finite for a suitable renormalization factor Z(γ) which depends on γ but on no other characteristic of C/sub γ/. This statement is made precise by introducing a regularization, or via a loop-integrand subtraction scheme specified by a normalization condition W/sub R/(C-bar/sub γ/) = 1 for an arbitrary but fixed loop C-bar/sub γ/. Next, if C/sub β/ is a loop which is smooth and simple except for a cross point of angles β, then W(C/sub β/) must be renormalized together with the loop functions of associated sets S/sup i//sub β/ = ]C/sup i/ 1 ,xxx, C/sup i//sub p/i] (i = 2,xxx,I) of loops C/sup i//sub q/ which coincide with certain parts of C/sub β/equivalentC 1 1 . Then W/sub R/(S/sup i//sub β/) = Z/sup i/j(β)W(S/sup j//sub β/) is finite for a suitable matrix Z/sup i/j

Mixed heavy–light matching in the Universal One-Loop Effective Action

International Nuclear Information System (INIS)

Ellis, Sebastian A.R.; Quevillon, Jérémie; You, Tevong; Zhang, Zhengkang

2016-01-01

Recently, a general result for evaluating the path integral at one loop was obtained in the form of the Universal One-Loop Effective Action. It may be used to derive effective field theory operators of dimensions up to six, by evaluating the traces of matrices in this expression, with the mass dependence encapsulated in the universal coefficients. Here we show that it can account for loops of mixed heavy–light particles in the matching procedure. Our prescription for computing these mixed contributions to the Wilson coefficients is conceptually simple. Moreover it has the advantage of maintaining the universal structure of the effective action, which we illustrate using the example of integrating out a heavy electroweak triplet scalar coupling to a light Higgs doublet. Finally we also identify new structures that were previously neglected in the universal results.

Photothermal IR spectroscopy with perforated membrane micromechanical resonators

DEFF Research Database (Denmark)

Kurek, Maksymilian

-IR method. In order to overcome them, string resonators were replaced by membranes. A reliable sampling technique was maintained by adding perforation to membranes and thereby essentially getting membrane porous filters. Membranes gave also access to fully integrated magnetic transduction that allowed...... for significant shrinkage and simplification of the system. An analytical model of a locally heated membrane was developed and confirmed through FEM simulations. Then, low stress silicon nitride perforated membranes were fabricated and characterized using two different experimental setups that employed optical...

Reduction of the N-component scalar model at the two-loop level

International Nuclear Information System (INIS)

Jakovac, A.

1996-01-01

Dimensional reduction of high temperature field theories improves IR features of their perturbative treatment. A crucial question is the following: What three-dimensional theory is representing the full system the most faithful way? A careful investigation of the induced three-dimensional counterterm structure of the finite temperature 4D O(N) symmetric scalar theory at the two-loop level leads to proposing the presence of nonlocal operators in the effective theory. A three-dimensional matching process is applied for the construction of the optimal local, superrenormalizable approximation. copyright 1996 The American Physical Society

Overexpression of IRS2 in isolated pancreatic islets causes proliferation and protects human β-cells from hyperglycemia-induced apoptosis

International Nuclear Information System (INIS)

Mohanty, S.; Spinas, G.A.; Maedler, K.; Zuellig, R.A.; Lehmann, R.; Donath, M.Y.; Trueb, T.; Niessen, M.

2005-01-01

Studies in vivo indicate that IRS2 plays an important role in maintaining functional β-cell mass. To investigate if IRS2 autonomously affects β-cells, we have studied proliferation, apoptosis, and β-cell function in isolated rat and human islets after overexpression of IRS2 or IRS1. We found that β-cell proliferation was significantly increased in rat islets overexpressing IRS2 while IRS1 was less effective. Moreover, proliferation of a β-cell line, INS-1, was decreased after repression of Irs2 expression using RNA oligonucleotides. Overexpression of IRS2 in human islets significantly decreased apoptosis of β-cells, induced by 33.3 mM D-glucose. However, IRS2 did not protect cultured rat islets against apoptosis in the presence of 0.5 mM palmitic acid. Overexpression of IRS2 in isolated rat islets significantly increased basal and D-glucose-stimulated insulin secretion as determined in perifusion experiments. Therefore, IRS2 is sufficient to induce proliferation in rat islets and to protect human β-cells from D-glucose-induced apoptosis. In addition, IRS2 can improve β-cell function. Our results indicate that IRS2 acts autonomously in β-cells in maintenance and expansion of functional β-cell mass in vivo

Availability analysis of nuclear power plant system with the consideration of logical loop structures

International Nuclear Information System (INIS)

Matsuoka, Takeshi

2013-01-01

Nuclear power plants have logical loop structures in their system configuration. The typical example is a power source system, that is, a nuclear plant generates electricity and it is used for the operation of pumps in the plant. For the reliability or availability analysis of nuclear power plants, it is necessary to treat accurately logical loop structures. Authors have proposed an exact method for solving logical loop structure in reliability analysis, and generalized method has recently been presented. A nuclear power plant system is taken up and essential parts of logical loop structures are modeled into relatively simple form. The procedure to solve a loop structure is shown in which the proposed generalized method is applied, and availability of the system with loop structure is accurately solved. The analysis results indicate that reconsideration of present plant operating procedure should be made for the increase of safety of nuclear power plant in case of 'Loss of offsite power' incident. The analysis results also show an important role of loop structures for maintaining the overall system availability. The analysis procedure is also useful in effectively designing high reliable systems. (author)

Heating and dynamics of two flare loop systems observed by AIA and EIS

Energy Technology Data Exchange (ETDEWEB)

Li, Y.; Ding, M. D. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Qiu, J., E-mail: yingli@nju.edu.cn [Department of Physics, Montana State University, Bozeman, MT 59717 (United States)

2014-02-01

We investigate heating and evolution of flare loops in a C4.7 two-ribbon flare on 2011 February 13. From Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) imaging observations, we can identify two sets of loops. Hinode/EUV Imaging Spectrometer (EIS) spectroscopic observations reveal blueshifts at the feet of both sets of loops. The evolution and dynamics of the two sets are quite different. The first set of loops exhibits blueshifts for about 25 minutes followed by redshifts, while the second set shows stronger blueshifts, which are maintained for about one hour. The UV 1600 observation by AIA also shows that the feet of the second set of loops brighten twice. These suggest that continuous heating may be present in the second set of loops. We use spatially resolved UV light curves to infer heating rates in the few tens of individual loops comprising the two loop systems. With these heating rates, we then compute plasma evolution in these loops with the 'enthalpy-based thermal evolution of loops' model. The results show that, for the first set of loops, the synthetic EUV light curves from the model compare favorably with the observed light curves in six AIA channels and eight EIS spectral lines, and the computed mean enthalpy flow velocities also agree with the Doppler shift measurements by EIS. For the second set of loops modeled with twice-heating, there are some discrepancies between modeled and observed EUV light curves in low-temperature bands, and the model does not fully produce the prolonged blueshift signatures as observed. We discuss possible causes for the discrepancies.

Exchange bias and perpendicular anisotropy study of ultrathin Pt-Co-Pt-IrMn multilayers sputtered on float glass

Science.gov (United States)

Laval, M.; Lüders, U.; Bobo, J. F.

2007-09-01

We have prepared ultrathin Pt-Co-Pt-IrMn polycrystalline multilayers on float-glass substrates by DC magnetron sputtering. We have determined the optimal set of thickness for both Pt layers, the Co layer and the IrMn biasing layer so that these samples exhibit at the same time out-of-plane magnetic anisotropy and exchange bias. Kerr microscopy domain structure imaging evidences an increase of nucleation rate accompanied with inhomogeneous magnetic behavior in the case of exchange-biased films compared to Pt-Co-Pt trilayers. Polar hysteresis loops are measured in obliquely applied magnetic field conditions, allowing us to determine both perpendicular anisotropy effective constant Keff and exchange-bias coupling JE, which are significantly different from the ones determined by standard switching field measurements.

Exchange bias and perpendicular anisotropy study of ultrathin Pt-Co-Pt-IrMn multilayers sputtered on float glass

International Nuclear Information System (INIS)

Laval, M.; Lueders, U.; Bobo, J.F.

2007-01-01

We have prepared ultrathin Pt-Co-Pt-IrMn polycrystalline multilayers on float-glass substrates by DC magnetron sputtering. We have determined the optimal set of thickness for both Pt layers, the Co layer and the IrMn biasing layer so that these samples exhibit at the same time out-of-plane magnetic anisotropy and exchange bias. Kerr microscopy domain structure imaging evidences an increase of nucleation rate accompanied with inhomogeneous magnetic behavior in the case of exchange-biased films compared to Pt-Co-Pt trilayers. Polar hysteresis loops are measured in obliquely applied magnetic field conditions, allowing us to determine both perpendicular anisotropy effective constant K eff and exchange-bias coupling J E , which are significantly different from the ones determined by standard switching field measurements

NiTi bonded space regainer/maintainer

Directory of Open Access Journals (Sweden)

Negi K

2010-06-01

Full Text Available Early orthodontic interventions are often initiated in the developing dentition to promote favorable developmental changes. Interceptive orthodontic can eliminate or reduce the severity of a developing malocclusion, the complexity of orthodontic treatment, overall treatment time and cost. Premature loss of deciduous tooth or teeth can often destroy the integrity of normal occlusion. There are many space regaining and maintaining devices mentioned in literature. In this article, I present a simple space regaining method by a piece of nickel titanium (NiTi wire bonded between the teeth in active loop form, and the unique shape memory property of NiTi wire will upright or move the teeth and the lost space can be regained easily.

Parametric analysis of a dual loop Organic Rankine Cycle (ORC) system for engine waste heat recovery

International Nuclear Information System (INIS)

Song, Jian; Gu, Chun-wei

2015-01-01

Highlights: • A dual loop ORC system is designed for engine waste heat recovery. • The two loops are coupled via a shared heat exchanger. • The influence of the HT loop condensation parameters on the LT loop is evaluated. • Pinch point locations determine the thermal parameters of the LT loop. - Abstract: This paper presents a dual loop Organic Rankine Cycle (ORC) system consisting of a high temperature (HT) loop and a low temperature (LT) loop for engine waste heat recovery. The HT loop recovers the waste heat of the engine exhaust gas, and the LT loop recovers that of the jacket cooling water in addition to the residual heat of the HT loop. The two loops are coupled via a shared heat exchanger, which means that the condenser of the HT loop is the evaporator of the LT loop as well. Cyclohexane, benzene and toluene are selected as the working fluids of the HT loop. Different condensation temperatures of the HT loop are set to maintain the condensation pressure slightly higher than the atmosphere pressure. R123, R236fa and R245fa are chosen for the LT loop. Parametric analysis is conducted to evaluate the influence of the HT loop condensation temperature and the residual heat load on the LT loop. The simulation results reveal that under different condensation conditions of the HT loop, the pinch point of the LT loop appears at different locations, resulting in different evaporation temperatures and other thermal parameters. With cyclohexane for the HT loop and R245fa for the LT loop, the maximum net power output of the dual loop ORC system reaches 111.2 kW. Since the original power output of the engine is 996 kW, the additional power generated by the dual loop ORC system can increase the engine power by 11.2%.

Thermal analysis of reservoir structure versus capillary pumped loop

International Nuclear Information System (INIS)

Lin Hungwen; Lin Weikeng

2009-01-01

Capillary pumped loop (CPL) was already used in man-made satellites and space aircrafts with proven heat control technology. However, small-sized CPL had not yet made a breakthrough application in electronic components owing to poor heat-absorption capacity of evaporator structure. Hence, a small-scale CPL was designed for server in this research. The evaporator was designed with a circular groove and embedded with a high density polyethylene (HDPE) as a capillary structure to absorb working fluid. The influence of reservoir upon thermal resistance was also analyzed. The experimental results showed that, under a filling level of 72%, CPL with optimized design could remove 110 W energy while maintaining its temperature at 80 deg. C. Comparison of CPL with/without reservoir, the loop thermal resistance R th,loop was reduced by 0.14 deg. C/W and was able to increase the stability of CPL, too, the results confirmed that reservoir could enhance CPL performance and this technology will probably find application in electronics cooling for electronic devices

Liquid lithium loop system to solve challenging technology issues for fusion power plant

Science.gov (United States)

Ono, M.; Majeski, R.; Jaworski, M. A.; Hirooka, Y.; Kaita, R.; Gray, T. K.; Maingi, R.; Skinner, C. H.; Christenson, M.; Ruzic, D. N.

2017-11-01

Steady-state fusion power plant designs present major divertor technology challenges, including high divertor heat flux both in steady-state and during transients. In addition to these concerns, there are the unresolved technology issues of long term dust accumulation and associated tritium inventory and safety issues. It has been suggested that radiation-based liquid lithium (LL) divertor concepts with a modest lithium-loop could provide a possible solution for these outstanding fusion reactor technology issues, while potentially improving reactor plasma performance. The application of lithium (Li) in NSTX resulted in improved H-mode confinement, H-mode power threshold reduction, and reduction in the divertor peak heat flux while maintaining essentially Li-free core plasma operation even during H-modes. These promising results in NSTX and related modeling calculations motivated the radiative liquid lithium divertor concept and its variant, the active liquid lithium divertor concept, taking advantage of the enhanced or non-coronal Li radiation in relatively poorly confined divertor plasmas. To maintain the LL purity in a 1 GW-electric class fusion power plant, a closed LL loop system with a modest circulating capacity of ~1 l s-1 is envisioned. We examined two key technology issues: (1) dust or solid particle removal and (2) real time recovery of tritium from LL while keeping the tritium inventory level to an acceptable level. By running the LL-loop continuously, it can carry the dust particles and impurities generated in the vacuum vessel to the outside where the dust/impurities can be removed by relatively simple dust filter, cold trap and/or centrifugal separation systems. With ~1 l s-1 LL flow, even a small 0.1% dust content by weight (or 0.5 g s-1) suggests that the LL-loop could carry away nearly 16 tons of dust per year. In a 1 GW-electric (or ~3 GW fusion power) fusion power plant, about 0.5 g s-1 of tritium is needed to maintain the fusion fuel cycle

Image simulation for HardWare In the Loop simulation in EO domain

Science.gov (United States)

Cathala, Thierry; Latger, Jean

2015-10-01

Infrared camera as a weapon sub system for automatic guidance is a key component for military carrier such as missile for example. The associated Image Processing, that controls the navigation, needs to be intensively assessed. Experimentation in the real world is very expensive. This is the main reason why hybrid simulation also called HardWare In the Loop (HWIL) is more and more required nowadays. In that field, IR projectors are able to cast IR fluxes of photons directly onto the IR camera of a given weapon system, typically a missile seeker head. Though in laboratory, the missile is so stimulated exactly like in the real world, provided a realistic simulation tool enables to perform synthetic images to be displayed by the IR projectors. The key technical challenge is to render the synthetic images at the required frequency. This paper focuses on OKTAL-SE experience in this domain through its product SE-FAST-HWIL. It shows the methodology and Return of Experience from OKTAL-SE. Examples are given, in the frame of the SE-Workbench. The presentation focuses on trials on real operational complex 3D cases. In particular, three important topics, that are very sensitive with regards to IG performance, are detailed: first the 3D sea surface representation, then particle systems rendering especially to simulate flares and at last sensor effects modelling. Beyond "projection mode", some information will be given on the SE-FAST-HWIL new capabilities dedicated to "injection mode".

Boosted PWM open loop control of hydraulic proportional valves

International Nuclear Information System (INIS)

Amirante, R.; Innone, A.; Catalano, L.A.

2008-01-01

This paper presents an innovative open loop control technique for direct single stage hydraulic proportional valves whose response rate is significantly higher than that obtained by standard open loop control techniques, even comparable to more costly commercial closed loop systems. Different from standard open loop techniques, which provide the coil with a constant current proportional to the target position, the control strategy proposed in this paper employs the peak and hold (P and H) technique, widely used in Diesel engine modern supply systems, to boost the duty cycle value of the pulse width modulation (PWM) signal for a short time, namely during the spool displacement, while maintaining a lower duty cycle for holding the spool in the required opening position. The developed 'boosted PWM' technique only requires a low cost microcontroller, such as a peripheral interface controller (PIC) equipped with a metal oxide semiconductor (MOS) power driver. The PWM parameters are calibrated as a function of the spool displacement so as to maximize the response rate without introducing overshoots: the collected data are stored in the PIC. Different valve opening procedures with step response have been compared to demonstrate the merits of the proposed boosted PWM technique. No overshoots have been registered. Moreover, the proposed method is characterized by a significantly higher response rate with respect to a standard open loop control, which approximately has the same cost. Similar experimental tests show that the proposed boosted PWM technique has a response rate even higher than that provided by the more costly commercial closed loop system mounted on the valve, and it produces no overshoots

Boosted PWM open loop control of hydraulic proportional valves

Energy Technology Data Exchange (ETDEWEB)

Amirante, R.; Catalano, L.A. [Dipartimento di Ingegneria Meccanica e Gestionale, Politecnico di Bari, Via Re David 200, 70125 Bari (Italy); Innone, A. [Universita degli Studi di Foggia, via Napoli, 25 Foggia (Italy)

2008-08-15

This paper presents an innovative open loop control technique for direct single stage hydraulic proportional valves whose response rate is significantly higher than that obtained by standard open loop control techniques, even comparable to more costly commercial closed loop systems. Different from standard open loop techniques, which provide the coil with a constant current proportional to the target position, the control strategy proposed in this paper employs the peak and hold (P and H) technique, widely used in Diesel engine modern supply systems, to boost the duty cycle value of the pulse width modulation (PWM) signal for a short time, namely during the spool displacement, while maintaining a lower duty cycle for holding the spool in the required opening position. The developed 'boosted PWM' technique only requires a low cost microcontroller, such as a peripheral interface controller (PIC) equipped with a metal oxide semiconductor (MOS) power driver. The PWM parameters are calibrated as a function of the spool displacement so as to maximize the response rate without introducing overshoots: the collected data are stored in the PIC. Different valve opening procedures with step response have been compared to demonstrate the merits of the proposed boosted PWM technique. No overshoots have been registered. Moreover, the proposed method is characterized by a significantly higher response rate with respect to a standard open loop control, which approximately has the same cost. Similar experimental tests show that the proposed boosted PWM technique has a response rate even higher than that provided by the more costly commercial closed loop system mounted on the valve, and it produces no overshoots. (author)

Two-loop hard-thermal-loop thermodynamics with quarks

International Nuclear Information System (INIS)

Andersen, Jens O.; Petitgirard, Emmanuel; Strickland, Michael

2004-01-01

We calculate the quark contribution to the free energy of a hot quark-gluon plasma to two-loop order using hard-thermal-loop (HTL) perturbation theory. All ultraviolet divergences can be absorbed into renormalizations of the vacuum energy and the HTL quark and gluon mass parameters. The quark and gluon HTL mass parameters are determined self-consistently by a variational prescription. Combining the quark contribution with the two-loop HTL perturbation theory free energy for pure glue we obtain the total two-loop QCD free energy. Comparisons are made with lattice estimates of the free energy for N f =2 and with exact numerical results obtained in the large-N f limit

LoopIng: a template-based tool for predicting the structure of protein loops.

KAUST Repository

Messih, Mario Abdel; Lepore, Rosalba; Tramontano, Anna

2015-01-01

) and significant enhancements for long loops (11-20 residues). The quality of the predictions is robust to errors that unavoidably affect the stem regions when these are modeled. The method returns a confidence score for the predicted template loops and has

The recent and prospective developments of cooled IR FPAs for double application at Electron NRI

Science.gov (United States)

Arutunov, V. A.; Vasilyev, I. S.; Ivanov, V. G.; Prokofyev, A. E.

2003-09-01

The recent and prospective developments of monolithic silicon IR-Schottky-barrier staring focal plane arrays (IR SB FPAs), photodetector assembly, and digital thermal imaging cameras (TICs) at Electron National Research Institute (Electron NRI) are considered. Basic parameters for IR SB FPAs with 256x256 and 512x512 pixels, and TICs based on these arrays are presented. The problems emerged while proceeding from the developments of IR SB FPAs for the wavelength range from 3 μm to 5 μm to the developments of those ones for xLWIR range are indicated (an abrupt increase in the level of background architecture). Possibility for further improvement in basic parameters of IR SB FPAs are discussed (a decrease in threshold signal power down to 0.5-1.0"1013 W/element with an increase in quantum efficiency, a decrease in output noise and proceeding to Schottky barriers of degenerated semiconductor/silicon heterojunction, and implementation of these array parameters in photodetector assembly with improved thermal background shielding taking into consideration an optical structure of TIC for concrete application). It is concluded that relative simplicity of the technology and expected low cost of monolithic silicon IR SB FPAs with basic parameters compared with hybrid IR FPAs for the wavelength ranges from 3 μm to 5 μm and from 8 μm to 12 μm maintain large monolithic IR SB FPAs as a basis for developments of double application digital TICs in the Russian Federation.

Spin orientations of the spin-half Ir(4+) ions in Sr3NiIrO6, Sr2IrO4, and Na2IrO3: Density functional, perturbation theory, and Madelung potential analyses.

Science.gov (United States)

Gordon, Elijah E; Xiang, Hongjun; Köhler, Jürgen; Whangbo, Myung-Hwan

2016-03-21

The spins of the low-spin Ir(4+) (S = 1/2, d(5)) ions at the octahedral sites of the oxides Sr3NiIrO6, Sr2IrO4, and Na2IrO3 exhibit preferred orientations with respect to their IrO6 octahedra. We evaluated the magnetic anisotropies of these S = 1/2 ions on the basis of density functional theory (DFT) calculations including spin-orbit coupling (SOC), and probed their origin by performing perturbation theory analyses with SOC as perturbation within the LS coupling scheme. The observed spin orientations of Sr3NiIrO6 and Sr2IrO4 are correctly predicted by DFT calculations, and are accounted for by the perturbation theory analysis. As for the spin orientation of Na2IrO3, both experimental studies and DFT calculations have not been unequivocal. Our analysis reveals that the Ir(4+) spin orientation of Na2IrO3 should have nonzero components along the c- and a-axis directions. The spin orientations determined by DFT calculations are sensitive to the accuracy of the crystal structures employed, which is explained by perturbation theory analyses when interactions between adjacent Ir(4+) ions are taken into consideration. There are indications implying that the 5d electrons of Na2IrO3 are less strongly localized compared with those of Sr3NiIrO6 and Sr2IrO4. This implication was confirmed by showing that the Madelung potentials of the Ir(4+) ions are less negative in Na2IrO3 than in Sr3NiIrO6 and Sr2IrO4. Most transition-metal S = 1/2 ions do have magnetic anisotropies because the SOC induces interactions among their crystal-field split d-states, and the associated mixing of the states modifies only the orbital parts of the states. This finding cannot be mimicked by a spin Hamiltonian because this model Hamiltonian lacks the orbital degree of freedom, thereby leading to the spin-half syndrome. The spin-orbital entanglement for the 5d spin-half ions Ir(4+) is not as strong as has been assumed.

An RFID-Based Closed-Loop Wireless Power Transmission System for Biomedical Applications.

Science.gov (United States)

Kiani, Mehdi; Ghovanloo, Maysam

2010-04-01

This brief presents a standalone closed-loop wireless power transmission system that is built around a commercial off-the-shelf (COTS) radio-frequency identification (RFID) reader (TRF7960) operating at 13.56 MHz. It can be used for inductively powering implantable biomedical devices in a closed loop. Any changes in the distance and misalignment between transmitter and receiver coils in near-field wireless power transmission can cause a significant change in the received power, which can cause either a malfunction or excessive heat dissipation. RFID circuits are often used in an open loop. However, their back telemetry capability can be utilized to stabilize the received voltage on the implant. Our measurements showed that the delivered power to the transponder was maintained at 11.2 mW over a range of 0.5 to 2 cm, while the transmitter power consumption changed from 78 mW to 1.1 W. The closed-loop system can also oppose voltage variations as a result of sudden changes in the load current.

Deletion of Irs2 causes reduced kidney size in mice: role for inhibition of GSK3beta?

LENUS (Irish Health Repository)

Carew, Rosemarie M.

2010-07-06

Abstract Background Male Irs2-\\/- mice develop fatal type 2 diabetes at 13-14 weeks. Defects in neuronal proliferation, pituitary development and photoreceptor cell survival manifest in Irs2-\\/- mice. We identify retarded renal growth in male and female Irs2-\\/- mice, independent of diabetes. Results Kidney size and kidney:body weight ratio were reduced by approximately 20% in Irs2-\\/- mice at postnatal day 5 and was maintained in maturity. Reduced glomerular number but similar glomerular density was detected in Irs2-\\/- kidney compared to wild-type, suggesting intact global kidney structure. Analysis of insulin signalling revealed renal-specific upregulation of PKBβ\\/Akt2, hyperphosphorylation of GSK3β and concomitant accumulation of β-catenin in Irs2-\\/- kidney. Despite this, no significant upregulation of β-catenin targets was detected. Kidney-specific increases in Yes-associated protein (YAP), a key driver of organ size were also detected in the absence of Irs2. YAP phosphorylation on its inhibitory site Ser127 was also increased, with no change in the levels of YAP-regulated genes, suggesting that overall YAP activity was not increased in Irs2-\\/- kidney. Conclusions In summary, deletion of Irs2 causes reduced kidney size early in mouse development. Compensatory mechanisms such as increased β-catenin and YAP levels failed to overcome this developmental defect. These data point to Irs2 as an important novel mediator of kidney size.

Neocortical electrical stimulation for epilepsy : Closed-loop versus open-loop

NARCIS (Netherlands)

Vassileva, Albena; van Blooijs, Dorien; Leijten, Frans; Huiskamp, Geertjan

2018-01-01

The aim of this review is to evaluate whether open-loop or closed-loop neocortical electrical stimulation should be the preferred approach to manage seizures in intractable epilepsy. Twenty cases of open-loop neocortical stimulation with an implanted device have been reported, in 5 case studies.

detectIR: a novel program for detecting perfect and imperfect inverted repeats using complex numbers and vector calculation.

Science.gov (United States)

Ye, Congting; Ji, Guoli; Li, Lei; Liang, Chun

2014-01-01

Inverted repeats are present in abundance in both prokaryotic and eukaryotic genomes and can form DNA secondary structures--hairpins and cruciforms that are involved in many important biological processes. Bioinformatics tools for efficient and accurate detection of inverted repeats are desirable, because existing tools are often less accurate and time consuming, sometimes incapable of dealing with genome-scale input data. Here, we present a MATLAB-based program called detectIR for the perfect and imperfect inverted repeat detection that utilizes complex numbers and vector calculation and allows genome-scale data inputs. A novel algorithm is adopted in detectIR to convert the conventional sequence string comparison in inverted repeat detection into vector calculation of complex numbers, allowing non-complementary pairs (mismatches) in the pairing stem and a non-palindromic spacer (loop or gaps) in the middle of inverted repeats. Compared with existing popular tools, our program performs with significantly higher accuracy and efficiency. Using genome sequence data from HIV-1, Arabidopsis thaliana, Homo sapiens and Zea mays for comparison, detectIR can find lots of inverted repeats missed by existing tools whose outputs often contain many invalid cases. detectIR is open source and its source code is freely available at: https://sourceforge.net/projects/detectir.

Saccharomyces cerevisiae Linker Histone—Hho1p Maintains Chromatin Loop Organization during Ageing

Directory of Open Access Journals (Sweden)

Katya Uzunova

2013-01-01

Full Text Available Intricate, dynamic, and absolutely unavoidable ageing affects cells and organisms through their entire lifetime. Driven by diverse mechanisms all leading to compromised cellular functions and finally to death, this process is a challenge for researchers. The molecular mechanisms, the general rules that it follows, and the complex interplay at a molecular and cellular level are yet little understood. Here, we present our results showing a connection between the linker histones, the higher-order chromatin structures, and the process of chronological lifespan of yeast cells. By deleting the gene for the linker histone in Saccharomyces cerevisiae we have created a model for studying the role of chromatin structures mainly at its most elusive and so far barely understood higher-order levels of compaction in the processes of yeast chronological lifespan. The mutant cells demonstrated controversial features showing slower growth than the wild type combined with better survival during the whole process. The analysis of the global chromatin organization during different time points demonstrated certain loss of the upper levels of chromatin compaction in the cells without linker histone. The results underlay the importance of this histone for the maintenance of the chromatin loop structures during ageing.

A multiple-pass ring oscillator based dual-loop phase-locked loop

International Nuclear Information System (INIS)

Chen Danfeng; Ren Junyan; Deng Jingjing; Li Wei; Li Ning

2009-01-01

A dual-loop phase-locked loop (PLL) for wideband operation is proposed. The dual-loop architecture combines a coarse-tuning loop with a fine-tuning one, enabling a wide tuning range and low voltage-controlled oscillator (VCO) gain without poisoning phase noise and reference spur suppression performance. An analysis of the phase noise and reference spur of the dual-loop PLL is emphasized. A novel multiple-pass ring VCO is designed for the dual-loop application. It utilizes both voltage-control and current-control simultaneously in the delay cell. The PLL is fabricated in Jazz 0.18-μm RF CMOS technology. The measured tuning range is from 4.2 to 5.9 GHz. It achieves a low phase noise of -99 dBc/Hz - 1 MHz offset from a 5.5 GHz carrier.

A multiple-pass ring oscillator based dual-loop phase-locked loop

Energy Technology Data Exchange (ETDEWEB)

Chen Danfeng; Ren Junyan; Deng Jingjing; Li Wei; Li Ning, E-mail: dfchen@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

2009-10-15

A dual-loop phase-locked loop (PLL) for wideband operation is proposed. The dual-loop architecture combines a coarse-tuning loop with a fine-tuning one, enabling a wide tuning range and low voltage-controlled oscillator (VCO) gain without poisoning phase noise and reference spur suppression performance. An analysis of the phase noise and reference spur of the dual-loop PLL is emphasized. A novel multiple-pass ring VCO is designed for the dual-loop application. It utilizes both voltage-control and current-control simultaneously in the delay cell. The PLL is fabricated in Jazz 0.18-{mu}m RF CMOS technology. The measured tuning range is from 4.2 to 5.9 GHz. It achieves a low phase noise of -99 dBc/Hz - 1 MHz offset from a 5.5 GHz carrier.

Redoable Tie-Over Dressing Using Multiple Loop Silk Threads

Directory of Open Access Journals (Sweden)

Hyeon Jong Jo

2013-05-01

Full Text Available After skin grafting, to prevent hematoma or seroma collection at the graft site, a tie-over dressing has been commonly used. However, although the conventional tie-over dressing by suture is a useful method for securing a graft site, refixation is difficult when repeated tie-over dressing is needed. Therefore, we recommend a redoable tie-over dressing technique with multiple loops threads and connecting silk threads. After the raw surface of each of our cases was covered with a skin graft, multiple loop silk thread attached with nylon at the skin graft margin. We applied the ointment gauze and wet cotton/fluffy gauze over the skin graft, then fixed the dressing by connecting cross-counter multiple loop thread with connecting silk threads. When we opened the tie-over dressing by cutting the connecting silk threads, we repeated the tie-over dressing with the same method. The skin graft was taken successfully without hematoma or seroma collection or any other complications. In conclusion, we report a novel tie-over dressing enabling simple fixation of the dressing to maintain proper tension for wounds that require repetitive fixation. Further, with this reliable method, the skin grafts were well taken.

Redoable Tie-Over Dressing Using Multiple Loop Silk Threads

Directory of Open Access Journals (Sweden)

Hyeon Jong Jo

2013-05-01

Full Text Available After skin grafting, to prevent hematoma or seroma collection at the graft site, a tie-over dressing has been commonly used. However, although the conventional tie-over dressing by suture is a useful method for securing a graft site, refixation is difficult when repeated tieover dressing is needed. Therefore, we recommend a redoable tie-over dressing technique with multiple loops threads and connecting silk threads. After the raw surface of each of our cases was covered with a skin graft, multiple loop silk thread attached with nylon at the skin graft margin. We applied the ointment gauze and wet cotton/fluffy gauze over the skin graft, then fixed the dressing by connecting cross-counter multiple loop thread with connecting silk threads. When we opened the tie-over dressing by cutting the connecting silk threads, we repeated the tie-over dressing with the same method. The skin graft was taken successfully without hematoma or seroma collection or any other complications. In conclusion, we report a novel tie-over dressing enabling simple fixation of the dressing to maintain proper tension for wounds that require repetitive fixation. Further, with this reliable method, the skin grafts were well taken.

Sequence-structure relationships in RNA loops: establishing the basis for loop homology modeling.

Science.gov (United States)

Schudoma, Christian; May, Patrick; Nikiforova, Viktoria; Walther, Dirk

2010-01-01

The specific function of RNA molecules frequently resides in their seemingly unstructured loop regions. We performed a systematic analysis of RNA loops extracted from experimentally determined three-dimensional structures of RNA molecules. A comprehensive loop-structure data set was created and organized into distinct clusters based on structural and sequence similarity. We detected clear evidence of the hallmark of homology present in the sequence-structure relationships in loops. Loops differing by structures. Thus, our results support the application of homology modeling for RNA loop model building. We established a threshold that may guide the sequence divergence-based selection of template structures for RNA loop homology modeling. Of all possible sequences that are, under the assumption of isosteric relationships, theoretically compatible with actual sequences observed in RNA structures, only a small fraction is contained in the Rfam database of RNA sequences and classes implying that the actual RNA loop space may consist of a limited number of unique loop structures and conserved sequences. The loop-structure data sets are made available via an online database, RLooM. RLooM also offers functionalities for the modeling of RNA loop structures in support of RNA engineering and design efforts.

Research on tunable multiwavelength fiber lasers with two-section birefringence fibers and a nonlinear optical loop

Science.gov (United States)

Chen, Jiao; Tong, Zhengrong; Zhang, Weihua; Xue, Lifang; Pan, Honggang

2018-05-01

Two types of tunable multiwavelength fiber lasers based on two-section polarization maintaining fibers (PMFs) cascaded/in parallel and nonlinear optical loop are proposed and experimentally demonstrated. Two-section cascaded PMFs and two polarization controllers (PCs) form the two-stage Lyot filter, which can generate comb spectrum to achieve multiwavelength output. When two sections of PMFs are in parallel, PCs in two paths are adjusted to change the beam’s polarization to suppress the light of one branch, and then the light of the other branch passes through the cavity. Additionally, a nonlinear optical loop acts as an intensity-dependent component, which can suppress the mode competition to maintain a stable output of multiwavelength lasing. The nonlinear optical loop is made by a 3 dB coupler, a PC3, and a 200 m high nonlinear fiber. Two types of tunable multiwavelength fiber lasers can achieve tuning of the channel space and the number of lasing wavelengths by adjusting PC1 and PC2. The channel space of the multiwavelengh laser can be tuned at nearly 0.4, 0.68, and 0.92 nm. Meanwhile, the spectral range of multiwavelength lasing can be controlled by PC3 in the nonlinear optical loop, and the tuning range of two multiwavelength lasers is about 2.28 and 1.45 nm, respectively.

Suppression of superconductivity in Nb by IrMn in IrMn/Nb bilayers

KAUST Repository

Wu, B. L.

2013-10-10

Effect of antiferromagnet on superconductivity has been investigated in IrMn/Nb bilayers. Significant suppression of both transition temperature (Tc) and lower critical field (Hc1) of Nb is found in IrMn/Nb bilayers as compared to a single layer Nb of same thickness; the suppression effect is even stronger than that of a ferromagnet in NiFe/Nb bilayers. The addition of an insulating MgO layer at the IrMn-Nb interface nearly restores Tc to that of the single layer Nb, but Hc1 still remains suppressed. These results suggest that, in addition to proximity effect and magnetic impurity scattering, magnetostatic interaction also plays a role in suppressing superconductivity of Nb in IrMn/Nb bilayers. In addition to reduced Tc and Hc1, the IrMn layer also induces broadening in the transition temperature of Nb, which can be accounted for by a finite distribution of stray field from IrMn.

Operation of the nuclear fuel cycle test facilities -Operation of the hot test loop facilities

International Nuclear Information System (INIS)

Chun, S. Y.; Jeong, M. K.; Park, C. K.; Yang, S. K.; Won, S. Y.; Song, C. H.; Jeon, H. K.; Jeong, H. J.; Cho, S.; Min, K. H.; Jeong, J. H.

1997-01-01

A performance and reliability of a advanced nuclear fuel and reactor newly designed should be verified by performing the thermal hydraulics tests. In thermal hydraulics research team, the thermal hydraulics tests associated with the development of an advanced nuclear fuel and reactor haven been carried out with the test facilities, such as the Hot Test Loop operated under high temperature and pressure conditions, Cold Test Loop, RCS Loop and B and C Loop. The objective of this project is to obtain the available experimental data and to develop the advanced measuring techniques through taking full advantage of the facilities. The facilities operated by the thermal hydraulics research team have been maintained and repaired in order to carry out the thermal hydraulics tests necessary for providing the available data. The performance tests for the double grid type bottom end piece which was improved on the debris filtering effectivity were performed using the PWR-Hot Test Loop. The CANDU-Hot Test Loop was operated to carry out the pressure drop tests and strength tests of CANFLEX fuel. The Cold Test Loop was used to obtain the local velocity data in subchannel within HANARO fuel bundle and to study a thermal mixing characteristic of PWR fuel bundle. RCS thermal hydraulic loop was constructed and the experiments have been carried out to measure the critical heat flux. In B and C Loop, the performance tests for each component were carried out. (author). 19 tabs., 78 figs., 19 refs

Operation of the nuclear fuel cycle test facilities -Operation of the hot test loop facilities

Energy Technology Data Exchange (ETDEWEB)

Chun, S. Y.; Jeong, M. K.; Park, C. K.; Yang, S. K.; Won, S. Y.; Song, C. H.; Jeon, H. K.; Jeong, H. J.; Cho, S.; Min, K. H.; Jeong, J. H.

1997-01-01

A performance and reliability of a advanced nuclear fuel and reactor newly designed should be verified by performing the thermal hydraulics tests. In thermal hydraulics research team, the thermal hydraulics tests associated with the development of an advanced nuclear fuel and reactor haven been carried out with the test facilities, such as the Hot Test Loop operated under high temperature and pressure conditions, Cold Test Loop, RCS Loop and B and C Loop. The objective of this project is to obtain the available experimental data and to develop the advanced measuring techniques through taking full advantage of the facilities. The facilities operated by the thermal hydraulics research team have been maintained and repaired in order to carry out the thermal hydraulics tests necessary for providing the available data. The performance tests for the double grid type bottom end piece which was improved on the debris filtering effectivity were performed using the PWR-Hot Test Loop. The CANDU-Hot Test Loop was operated to carry out the pressure drop tests and strength tests of CANFLEX fuel. The Cold Test Loop was used to obtain the local velocity data in subchannel within HANARO fuel bundle and to study a thermal mixing characteristic of PWR fuel bundle. RCS thermal hydraulic loop was constructed and the experiments have been carried out to measure the critical heat flux. In B and C Loop, the performance tests for each component were carried out. (author). 19 tabs., 78 figs., 19 refs.

Basic Comparison of the Properties of the Loop and Frotte Yarns, Woven and Knitted Fabrics

Directory of Open Access Journals (Sweden)

Ewa Grabowska Katarzyna

2014-09-01

Full Text Available Both loop fancy yarns and frotte fancy yarns belong to the group of yarns with continuous effects. The difference between frotte and loop yarn relies on the fact that the loop yarn is constructed with two core yarns and the frotte yarn is constructed with only one core yarn. The differences are evident in the shape of these two types of fancy yarns. These shape differences are the functions of the tensions of component yarns during the twisting process. The shape and construction of the fancy yarn influence its properties. The properties of loop and frotte fancy yarns, woven and knitted fabrics are compared in this article in order to find out the optimal yarn’s and fabric’s production condition to satisfy the final user and maintain low production costs. In terms of economy aspects only, the frotte fancy yarns are believed to be cheaper in production due to lower quantity of components utilize for their production to compare with loop fancy yarns, under conditions of the same settings of ring twisting frame.

Mechanical properties of different types of space maintainers

Science.gov (United States)

Beldiman, M.-A.; Mârţu, I.; Leiţoiu, B.; Luchian, I.; Lupescu, O.; Bârcă, E. S.

2015-11-01

Currently, inside the oral cavity, the dental space maintainers are subjected to forces exerted on them when performing various functions; therefore, it is important to know how each of these mechanisms behave and respond to forces that are applied directly to them. The mechanical properties of the materials used in dentistry are defined by a set of characteristics representing the behaviour of their particular working conditions and it is qualitatively expressed by a number of parameters.The study aimed to determine the pressing force that can be taken by four 4 types of space maintainers frequently used in practice - fixed and removable, applied on four samples realized with human teeth extracted for orthodontic purposes. Static tests were carried out on a machine type short WDW-5 EC with a maximum force of 5 kN and a loading speed of 5 mm/min by a special testing machine, with an innovative appliance; data recording was automatically performed, using a computer with a special program that present the specific diagrams. Experimental determinations included the following aspects: to determine the maximum force that can be supported by each sample, and to observe the deformations. The values obtained indicate that the best option in terms of behavior under the conditions specified is the removable appliance, and the less functional version is the fixed space maintainer using brackets. According to tests conducted, the fracture strength was found to be more important for fixed space maintainers (band and loop, for example) so, in practice is using more frequent these types of space maintainers.

LOOP CALCULUS AND BELIEF PROPAGATION FOR Q-ARY ALPHABET: LOOP TOWER

Energy Technology Data Exchange (ETDEWEB)

CHERTKOV, MICHAEL [Los Alamos National Laboratory; CHERNYAK, VLADIMIR [Los Alamos National Laboratory

2007-01-10

Loop calculus introduced in [1], [2] constitutes a new theoretical tool that explicitly expresses symbol Maximum-A-Posteriori (MAP) solution of a general statistical inference problem via a solution of the Belief Propagation (BP) equations. This finding brought a new significance to the BP concept, which in the past was thought of as just a loop-free approximation. In this paper they continue a discussion of the Loop Calculus, partitioning the results into three Sections. In Section 1 they introduce a new formulation of the Loop Calculus in terms of a set of transformations (gauges) that keeping the partition function of the problem invariant. The full expression contains two terms referred to as the 'ground state' and 'excited states' contributions. The BP equations are interpreted as a special (BP) gauge fixing condition that emerges as a special orthogonality constraint between the ground state and excited states, which also selects loop contributions as the only surviving ones among the excited states. In Section 2 they demonstrate how the invariant interpretation of the Loop Calculus, introduced in Section 1, allows a natural extension to the case of a general q-ary alphabet, this is achieved via a loop tower sequential construction. The ground level in the tower is exactly equivalent to assigning one color (out of q available) to the 'ground state' and considering all 'excited' states colored in the remaining (q-1) colors, according to the loop calculus rule. Sequentially, the second level in the tower corresponds to selecting a loop from the previous step, colored in (q-1) colors, and repeating the same ground vs excited states splitting procedure into one and (q-2) colors respectively. The construction proceeds till the full (q-1)-levels deep loop tower (and the corresponding contributions to the partition function) are established. In Section 3 they discuss an ultimate relation between the loop calculus and the Bethe

Magnetic and exchange bias properties of YCo thin films and IrMn/YCo bilayers

Science.gov (United States)

Venkat Narayana, M.; Manivel Raja, M.; Jammalamadaka, S. Narayana

2018-02-01

We report on the structural and magnetic properties of YCo thin films and IrMn/YCo bilayers. X-ray diffraction infer that all the films are amorphous in nature. Magnetization versus magnetic field measurements reveal room temperature soft ferromagnetism in all the YCo films. Thin films which were grown at 100 W sputter power with growth rates of 0.677, 0.694 and 0.711 Å/sec show better morphology and composition than 50 W (0.333, 0.444 and 0.277 Å/sec) grown films. Perpendicular exchange bias in as deposited bilayers is evident for IrMn/YCo bilayers. Exchange bias (EB) decreases in case of in plane measurements and enhances for out of plane measurements after perpendicular field annealing. EB is more in case of out of plane direction due to large perpendicular anisotropy in comparison with in plane direction. Above the critical thickness, EB variation is explained on the basis of random field model in the Heisenberg regime, which has been proposed by Malozemoff. Indeed there exists an inverse relationship between EB and IrMn layer thickness. Evidenced vertical shift apart from the horizontal shift for magnetization loops is attributed to frozen magnetic moments in one of the layers at the interface. Present results would prove to be helpful in spintronic device applications.

A closed-loop photon beam control study for the Advanced Light Source

International Nuclear Information System (INIS)

Portmann, G.; Bengtsson, J.

1993-05-01

The third generation Advanced Light Source (ALS) will produce extremely bright photon beams using undulators and wigglers. In order to position the photon beams accurate to the micron level, a closed-loop feedback system is being developed. Using photon position monitors and dipole corrector magnets, a closed-loop system can automatically compensate for modeling uncertainties and exogenous disturbances. The following paper will present a dynamics model for the perturbations of the closed orbit of the electron beam in the ALS storage ring including the vacuum chamber magnetic field penetration effects. Using this reference model, two closed-loop feedback algorithms will be compared -- a classical PI controller and a two degree-of-freedom approach. The two degree-of-freedom method provides superior disturbance rejection while maintaining the desired performance goals. Both methods will address the need to gain schedule the controller due to the time varying dynamics introduced by changing field strengths when scanning the insertion devices

Introduction to Loop Heat Pipes

Science.gov (United States)

Ku, Jentung

2015-01-01

This is the presentation file for the short course Introduction to Loop Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. This course will discuss operating principles and performance characteristics of a loop heat pipe. Topics include: 1) pressure profiles in the loop; 2) loop operating temperature; 3) operating temperature control; 4) loop startup; 4) loop shutdown; 5) loop transient behaviors; 6) sizing of loop components and determination of fluid inventory; 7) analytical modeling; 8) examples of flight applications; and 9) recent LHP developments.

Reactor loops at Chalk River

International Nuclear Information System (INIS)

Sochaski, R.O.

1962-07-01

This report describes broadly the nine in-reactor loops, and their components, located in and around the NRX and NRU reactors at Chalk River. First an introduction and general description is given of the loops and their function, supplemented with a table outlining some loop specifications and nine simplified flow sheets, one for each individual loop. The report then proceeds to classify each loop into two categories, the 'main loop circuit' and the 'auxiliary circuit', and descriptions are given of each circuit's components in turn. These components, in part, are comprised of the main loop pumps, the test section, loop heaters, loop coolers, delayed-neutron monitors, surge tank, Dowtherm coolers, loop piping. Here again photographs, drawings and tables are included to provide a clearer understanding of the descriptive literature and to include, in tables, some specifications of the more important components in each loop. (author)

Reconfiguration of the NRAD delay loop for proposed 1 MW operations

International Nuclear Information System (INIS)

Heidel, C.C.; Richards, W.J.; Pruett, D.P.

1984-01-01

Neutron radiography is provided by the NRAD reactor facility, which is located beneath the HFEF hot cell. The NRAD reactor is a TRIGA reactor and is operated at a steady-state power level of 250 kw solely for neutron radiography and the development of radiography techniques. When the NRAD facility was designed and constructed, an operating power level of 250 kw was considered to be adequate for obtaining radiographs of the type of specimens envisaged at that time. Since that time a second radiography station was installed and the thickness of the specimens being radiographed is greater than was initially envisaged. In order to decrease exposure times, the reactor power level is to be increased to 1 Mw. The present delay loop can not to be used at 1 Mw operation, because the passage way where the primary piping exits the reactor room must be maintained less than 1 MR/hr. To obtain the needed delay before the primary water exits the reactor room using the present internal delay loop system would require two more delay loops of the same size to be placed in series with the present delay loop. Because the NRAD reactor tank is small this is not possible; therefore, the delay must take place external to the reactor tank. The delay loop will have to be located in a shielded area to allow the decay of N 16 . The best location for the delay tank will be in the east radiography

A closed loop wireless power transmission system using a commercial RFID transceiver for biomedical applications.

Science.gov (United States)

Kiani, Mehdi; Ghovanloo, Maysam

2009-01-01

This paper presents a standalone closed loop wireless power transmission system that is built around a commercial off-the-shelf (COTS) radio frequency identification (RFID) transceiver (MLX90121) operating at 13.56 MHz. It can be used for inductively powering implantable biomedical devices in a closed loop fashion. Any changes in the distance and misalignment between transmitter and receiver coils in near-field wireless power transmission can cause a significant change in the received power, which can cause either malfunction or excessive heat dissipation. RFID transceivers are often used open loop. However, their back telemetry capability can be utilized to stabilize the received voltage on the implant. Our measurements showed that the delivered power to the transponder was maintained at 1.48 mW over a range of 6 to 12 cm, while the transmitter power consumption changed from 0.3 W to 1.21 W. The closed loop system can also oppose voltage variations as a result of sudden changes in load current.

Coupled hydrodynamic-structural analysis of an integral flowing sodium test loop in the TREAT reactor

International Nuclear Information System (INIS)

Zeuch, W.R.; A-Moneim, M.T.

1979-01-01

A hydrodynamic-structural response analysis of the Mark-IICB loop was performed for the TREAT (Transient Reactor Test Facility) test AX-1. Test AX-1 is intended to provide information concerning the potential for a vapor explosion in an advanced-fueled LMFBR. The test will be conducted in TREAT with unirradiated uranium-carbide fuel pins in the Mark-IICB integral flowing sodium loop. Our analysis addressed the ability of the experimental hardware to maintain its containment integrity during the reference accident postulated for the test. Based on a thermal-hydraulics analysis and assumptions for fuel-coolant interaction in the test section, a pressure pulse of 144 MPa maximum pressure and pulse width of 1.32 ms has been calculated as the reference accident. The response of the test loop to the pressure transient was obtained with the ICEPEL and STRAW codes. Modelling of the test section was completed with STRAW and the remainder of the loop was modelled by ICEPEL

Mesoporous silica nanoparticle supported PdIr bimetal catalyst for selective hydrogenation, and the significant promotional effect of Ir

Energy Technology Data Exchange (ETDEWEB)

Yang, Hui; Huang, Chao; Yang, Fan [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Yang, Xu [Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China); Du, Li [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China); Liao, Shijun, E-mail: chsjliao@scut.edu.cn [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China)

2015-12-01

Graphical abstract: A mesoporous silica nanoparticle (MSN) supported bimetal catalyst, PdIr/MSN, was prepared by a facile impregnation and hydrogen reduction method. The strong promotional effect of Ir was observed and thoroughly investigated. At the optimal molar ratio of Ir to Pd (N{sub Ir}/N{sub Pd} = 0.1), the activity of PdIr{sub 0.1}/MSN was up to eight times and 28 times higher than that of monometallic Pd/MSN and Ir/MSN, respectively. The catalysts were characterized comprehensively by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and hydrogen temperature programmed reduction, which revealed that the promotional effect of Ir may be due to the enhanced dispersion of active components on the MSN, and to the intensified Pd–Ir electronic interaction caused by the addition of Ir. - Highlights: • Mesoporous nanoparticles were synthesized and used as support for metal catalyst. • PdIr bimetallic catalyst exhibited significantly improved hydrogenation activity. • The strong promotion of Ir was recognized firstly and investigated intensively. • PdIr exhibits 18 times higher activity than Pd to the hydrogenation of nitrobenzene. - Abstract: A mesoporous silica nanoparticle (MSN) supported bimetal catalyst, PdIr/MSN, was prepared by a facile impregnation and hydrogen reduction method. The strong promotional effect of Ir was observed and thoroughly investigated. At the optimal molar ratio of Ir to Pd (N{sub Ir}/N{sub Pd} = 0.1), the activity of PdIr{sub 0.1}/MSN was up to eight times and 28 times higher than that of monometallic Pd/MSN and Ir/MSN, respectively. The catalysts were characterized comprehensively by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and hydrogen temperature programmed reduction, which revealed that the promotional effect of Ir may be due to the enhanced dispersion of active components on the MSN, and to the intensified Pd–Ir electronic interaction

Hybrid nanomaterial and its applications: IR sensing and energy harvesting

Science.gov (United States)

Tseng, Yi-Hsuan

sensitivity and detection limit were due to the temperature difference between the two junctions formed by the nanohybrid thin film and copper-wire electrodes under asymmetric IR illumination, and the difference between the effective Seebeck coefficient of the nanohybrid thin film and that of the Cu wires. The IR sensor embedded in polydimethylsiloxane (PDMS) layers was also fabricated and tested to demonstrate its potential application as a flexible IR sensor. In another application, energy harvesting, a new type of thermoelectric microgenerator enabled with the SWNTs-CuS nanoparticles hybrid nanomaterial, was fabricated. This type of microgenerator did not require any cooling or heat sink element to maintain the temperature difference or gradient in the device. Instead, the integrated nanomaterials in the device enhanced the local temperature and thus produced and maintained an intrinsic temperature difference or gradient across the microgenerator, thereby converting light and heat directly into electricity. In order to enhance the maximum output voltage, the incoming light had to be focused on the thin film region. A tunable lens was fabricated to collect and focus the ambient light on the thin film to enhance the output voltage of the microgenerators. The tunable lens was fabricated with a flexible polymer, PDMS. Therefore, the focal length of the tunable lens can be adjusted by pumping oil into the lens chamber to deform a PDMS membrane, resulting in the changed focus of the lens. In order to enhance the output power, two different arrays of thermoelectric generators in series and in parallel were fabricated. A hybrid nanomaterial thin film was also used to enhance the temperature gradient of the thermoelectric generators. For the devices in series, the generated voltage of all thermoelectric generators was combined together to enhance the output voltage. With the device in parallel, it can be used to combine all of the current of thermoelectric generators together to

ROBUST CONTROL OF END-TIDAL CO2 USING THE H∞ LOOP-SHAPING APPROACH

Directory of Open Access Journals (Sweden)

Anake Pomprapa

2013-12-01

Full Text Available Mechanically ventilated patients require appropriate settings of respiratory control variables to maintain acceptable gas exchange. To control the carbon dioxide (CO2 level effectively and automatically, system identification based on a human subject was performed using a linear affine model and a nonlinear Hammerstein structure. Subsequently, a robust controller was designed using the H∞ loop-shaping approach, which synthesizes the optimal controller based on a specific objective by achieving stability with guaranteed performance. For demonstration purposes, the closed-loop control ventilation system was successfully tested in a human volunteer. The experimental results indicate that the blood CO2 level may indeed be controlled noninvasively by measuring end-tidal CO2 from expired air. Keeping the limited amount of experimental data in mind, we conclude that H∞ loop-shaping may be a promising technique for control of mechanical ventilation in patients with respiratory insufficiency.

BOOTES-IR: near IR follow-up GRB observations by a robotic system

International Nuclear Information System (INIS)

Castro-Tirado, A.J.; Postrigo, A. de Ugarte; Jelinek, M.

2005-01-01

BOOTES-IR is the extension of the BOOTES experiment, which operates in Southern Spain since 1998, to the near IR (NIR). The goal is to follow up the early stage of the gamma ray burst (GRB) afterglow emission in the NIR, alike BOOTES does already at optical wavelengths. The scientific case that drives the BOOTES-IR performance is the study of GRBs with the support of spacecraft like INTEGRAL, SWIFT and GLAST. Given that the afterglow emission in both, the NIR and the optical, in the instances immediately following a GRB, is extremely bright (reached V = 8.9 in one case), it should be possible to detect this prompt emission at NIR wavelengths too. The combined observations by BOOTES-IR and BOOTES-1 and BOOTES-2 will allow for real time identification of trustworthy candidates to have a high redshift (z > 5). It is expected that, few minutes after a GRB, the IR magnitudes be H ∼ 7-10, hence very high quality spectra can be obtained for objects as far as z = 10 by larger instruments

The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues

International Nuclear Information System (INIS)

Groessle, Robin

2015-01-01

The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

Distribution of sizes of erased loops for loop-erased random walks

OpenAIRE

Dhar, Deepak; Dhar, Abhishek

1997-01-01

We study the distribution of sizes of erased loops for loop-erased random walks on regular and fractal lattices. We show that for arbitrary graphs the probability $P(l)$ of generating a loop of perimeter $l$ is expressible in terms of the probability $P_{st}(l)$ of forming a loop of perimeter $l$ when a bond is added to a random spanning tree on the same graph by the simple relation $P(l)=P_{st}(l)/l$. On $d$-dimensional hypercubical lattices, $P(l)$ varies as $l^{-\\sigma}$ for large $l$, whe...

Control Performance Management in Industrial Automation Assessment, Diagnosis and Improvement of Control Loop Performance

CERN Document Server

Jelali, Mohieddine

2013-01-01

Control Performance Management in Industrial Automation provides a coherent and self-contained treatment of a group of methods and applications of burgeoning importance to the detection and solution of problems with control loops that are vital in maintaining product quality, operational safety, and efficiency of material and energy consumption in the process industries. The monograph deals with all aspects of control performance management (CPM), from controller assessment (minimum-variance-control-based and advanced methods), to detection and diagnosis of control loop problems (process non-linearities, oscillations, actuator faults), to the improvement of control performance (maintenance, re-design of loop components, automatic controller re-tuning). It provides a contribution towards the development and application of completely self-contained and automatic methodologies in the field. Moreover, within this work, many CPM tools have been developed that goes far beyond available CPM packages. Control Perform...

Numerical method for IR background and clutter simulation

Science.gov (United States)

Quaranta, Carlo; Daniele, Gina; Balzarotti, Giorgio

1997-06-01

The paper describes a fast and accurate algorithm of IR background noise and clutter generation for application in scene simulations. The process is based on the hypothesis that background might be modeled as a statistical process where amplitude of signal obeys to the Gaussian distribution rule and zones of the same scene meet a correlation function with exponential form. The algorithm allows to provide an accurate mathematical approximation of the model and also an excellent fidelity with reality, that appears from a comparison with images from IR sensors. The proposed method shows advantages with respect to methods based on the filtering of white noise in time or frequency domain as it requires a limited number of computation and, furthermore, it is more accurate than the quasi random processes. The background generation starts from a reticule of few points and by means of growing rules the process is extended to the whole scene of required dimension and resolution. The statistical property of the model are properly maintained in the simulation process. The paper gives specific attention to the mathematical aspects of the algorithm and provides a number of simulations and comparisons with real scenes.

PHOTOSPHERIC PROPERTIES OF WARM EUV LOOPS AND HOT X-RAY LOOPS

Energy Technology Data Exchange (ETDEWEB)

Kano, R. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Ueda, K. [Department of Astronomy, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Tsuneta, S., E-mail: ryouhei.kano@nao.ac.jp [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan)

2014-02-20

We investigate the photospheric properties (vector magnetic fields and horizontal velocity) of a well-developed active region, NOAA AR 10978, using the Hinode Solar Optical Telescope specifically to determine what gives rise to the temperature difference between ''warm loops'' (1-2 MK), which are coronal loops observed in EUV wavelengths, and ''hot loops'' (>3 MK), coronal loops observed in X-rays. We found that outside sunspots, the magnetic filling factor in the solar network varies with location and is anti-correlated with the horizontal random velocity. If we accept that the observed magnetic features consist of unresolved magnetic flux tubes, this anti-correlation can be explained by the ensemble average of flux-tube motion driven by small-scale random flows. The observed data are consistent with a flux tube width of ∼77 km and horizontal flow at ∼2.6 km s{sup –1} with a spatial scale of ∼120 km. We also found that outside sunspots, there is no significant difference between warm and hot loops either in the magnetic properties (except for the inclination) or in the horizontal random velocity at their footpoints, which are identified with the Hinode X-Ray Telescope and the Transition Region and Coronal Explorer. The energy flux injected into the coronal loops by the observed photospheric motion of the magnetic fields is estimated to be 2 × 10{sup 6} erg s{sup –1} cm{sup –2}, which is the same for both warm and hot loops. This suggests that coronal properties (e.g., loop length) play a more important role in giving rise to temperature differences of active-region coronal loops than photospheric parameters.

TRF2 recruits RTEL1 to telomeres in S phase to promote t-loop unwinding.

Science.gov (United States)

Sarek, Grzegorz; Vannier, Jean-Baptiste; Panier, Stephanie; Petrini, John H J; Boulton, Simon J

2015-02-19

The helicase RTEL1 promotes t-loop unwinding and suppresses telomere fragility to maintain the integrity of vertebrate telomeres. An interaction between RTEL1 and PCNA is important to prevent telomere fragility, but how RTEL1 engages with the telomere to promote t-loop unwinding is unclear. Here, we establish that the shelterin protein TRF2 recruits RTEL1 to telomeres in S phase, which is required to prevent catastrophic t-loop processing by structure-specific nucleases. We show that the TRF2-RTEL1 interaction is mediated by a metal-coordinating C4C4 motif in RTEL1, which is compromised by the Hoyeraal-Hreidarsson syndrome (HHS) mutation, RTEL1(R1264H). Conversely, we define a TRF2(I124D) substitution mutation within the TRFH domain of TRF2, which eliminates RTEL1 binding and phenocopies the RTEL1(R1264H) mutation, giving rise to aberrant t-loop excision, telomere length heterogeneity, and loss of the telomere as a circle. These results implicate TRF2 in the recruitment of RTEL1 to facilitate t-loop disassembly at telomeres in S phase. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Inhibition of PTP1B Restores IRS1-Mediated Hepatic Insulin Signaling in IRS2-Deficient Mice

Science.gov (United States)

González-Rodríguez, Águeda; Gutierrez, Jose A. Mas; Sanz-González, Silvia; Ros, Manuel; Burks, Deborah J.; Valverde, Ángela M.

2010-01-01

OBJECTIVE Mice with complete deletion of insulin receptor substrate 2 (IRS2) develop hyperglycemia, impaired hepatic insulin signaling, and elevated gluconeogenesis, whereas mice deficient for protein tyrosine phosphatase (PTP)1B display an opposing hepatic phenotype characterized by increased sensitivity to insulin. To define the relationship between these two signaling pathways in the regulation of liver metabolism, we used genetic and pharmacological approaches to study the effects of inhibiting PTP1B on hepatic insulin signaling and expression of gluconeogenic enzymes in IRS2−/− mice. RESEARCH DESIGN AND METHODS We analyzed glucose homeostasis and insulin signaling in liver and isolated hepatocytes from IRS2−/− and IRS2−/−/PTP1B−/− mice. Additionally, hepatic insulin signaling was assessed in control and IRS2−/− mice treated with resveratrol, an antioxidant present in red wine. RESULTS In livers of hyperglycemic IRS2−/− mice, the expression levels of PTP1B and its association with the insulin receptor (IR) were increased. The absence of PTP1B in the double-mutant mice restored hepatic IRS1-mediated phosphatidylinositol (PI) 3-kinase/Akt/Foxo1 signaling. Moreover, resveratrol treatment of hyperglycemic IRS2−/− mice decreased hepatic PTP1B mRNA and inhibited PTP1B activity, thereby restoring IRS1-mediated PI 3-kinase/Akt/Foxo1 signaling and peripheral insulin sensitivity. CONCLUSIONS By regulating the phosphorylation state of IR, PTB1B determines sensitivity to insulin in liver and exerts a unique role in the interplay between IRS1 and IRS2 in the modulation of hepatic insulin action. PMID:20028942

Validation of the thermal code of RadTherm-IR, IR-Workbench, and F-TOM

Science.gov (United States)

Schwenger, Frédéric; Grossmann, Peter; Malaplate, Alain

2009-05-01

System assessment by image simulation requires synthetic scenarios that can be viewed by the device to be simulated. In addition to physical modeling of the camera, a reliable modeling of scene elements is necessary. Software products for modeling of target data in the IR should be capable of (i) predicting surface temperatures of scene elements over a long period of time and (ii) computing sensor views of the scenario. For such applications, FGAN-FOM acquired the software products RadTherm-IR (ThermoAnalytics Inc., Calumet, USA; IR-Workbench (OKTAL-SE, Toulouse, France). Inspection of the accuracy of simulation results by validation is necessary before using these products for applications. In the first step of validation, the performance of both "thermal solvers" was determined through comparison of the computed diurnal surface temperatures of a simple object with the corresponding values from measurements. CUBI is a rather simple geometric object with well known material parameters which makes it suitable for testing and validating object models in IR. It was used in this study as a test body. Comparison of calculated and measured surface temperature values will be presented, together with the results from the FGAN-FOM thermal object code F-TOM. In the second validation step, radiances of the simulated sensor views computed by RadTherm-IR and IR-Workbench will be compared with radiances retrieved from the recorded sensor images taken by the sensor that was simulated. Strengths and weaknesses of the models RadTherm-IR, IR-Workbench and F-TOM will be discussed.

Up-regulation of K{sub ir}2.1 by ER stress facilitates cell death of brain capillary endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Kito, Hiroaki [Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya (Japan); Yamazaki, Daiju [Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya (Japan); Department of Biological Chemistry, Kyoto University, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Department of Molecular Neurobiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Ohya, Susumu; Yamamura, Hisao [Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya (Japan); Asai, Kiyofumi [Department of Molecular Neurobiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Imaizumi, Yuji, E-mail: yimaizum@phar.nagoya-cu.ac.jp [Department of Molecular and Cellular Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya (Japan)

2011-07-29

Highlights: {yields} We found that application of endoplasmic reticulum (ER) stress with tunicamycin to brain capillary endothelial cells (BCECs) induced cell death. {yields} The ER stress facilitated the expression of inward rectifier K{sup +} channel (K{sub ir}2.1) and induced sustained membrane hyperpolarization. {yields} The membrane hyperpolarization induced sustained Ca{sup 2+} entry through voltage-independent nonspecific cation channels and consequently facilitated cell death. {yields} The K{sub ir}2.1 up-regulation by ER stress is, at least in part, responsible for cell death of BCECs under pathological conditions. -- Abstract: Brain capillary endothelial cells (BCECs) form blood brain barrier (BBB) to maintain brain homeostasis. Cell turnover of BCECs by the balance of cell proliferation and cell death is critical for maintaining the integrity of BBB. Here we found that stimuli with tunicamycin, endoplasmic reticulum (ER) stress inducer, up-regulated inward rectifier K{sup +} channel (K{sub ir}2.1) and facilitated cell death in t-BBEC117, a cell line derived from bovine BCECs. The activation of K{sub ir} channels contributed to the establishment of deeply negative resting membrane potential in t-BBEC117. The deep resting membrane potential increased the resting intracellular Ca{sup 2+} concentration due to Ca{sup 2+} influx through non-selective cation channels and thereby partly but significantly regulated cell death in t-BBEC117. The present results suggest that the up-regulation of K{sub ir}2.1 is, at least in part, responsible for cell death/cell turnover of BCECs induced by a variety of cellular stresses, particularly ER stress, under pathological conditions.

One-loop potential with scale invariance and effective operators

CERN Document Server

Ghilencea, D M

2016-01-01

We study quantum corrections to the scalar potential in classically scale invariant theories, using a manifestly scale invariant regularization. To this purpose, the subtraction scale $\\mu$ of the dimensional regularization is generated after spontaneous scale symmetry breaking, from a subtraction function of the fields, $\\mu(\\phi,\\sigma)$. This function is then uniquely determined from general principles showing that it depends on the dilaton only, with $\\mu(\\sigma)\\sim \\sigma$. The result is a scale invariant one-loop potential $U$ for a higgs field $\\phi$ and dilaton $\\sigma$ that contains an additional {\\it finite} quantum correction $\\Delta U(\\phi,\\sigma)$, beyond the Coleman Weinberg term. $\\Delta U$ contains new, non-polynomial effective operators like $\\phi^6/\\sigma^2$ whose quantum origin is explained. A flat direction is maintained at the quantum level, the model has vanishing vacuum energy and the one-loop correction to the mass of $\\phi$ remains small without tuning (of its self-coupling, etc) bey...

Design validation and performance of closed loop gas recirculation system

International Nuclear Information System (INIS)

Kalmani, S.D.; Majumder, G.; Mondal, N.K.; Shinde, R.R.; Joshi, A.V.

2016-01-01

A pilot experimental set up of the India Based Neutrino Observatory's ICAL detector has been operational for the last 4 years at TIFR, Mumbai. Twelve glass RPC detectors of size 2 × 2 m 2 , with a gas gap of 2 mm are under test in a closed loop gas recirculation system. These RPCs are continuously purged individually, with a gas mixture of R134a (C 2 H 2 F 4 ), isobutane (iC 4 H 10 ) and sulphur hexafluoride (SF 6 ) at a steady rate of 360 ml/h to maintain about one volume change a day. To economize gas mixture consumption and to reduce the effluents from being released into the atmosphere, a closed loop system has been designed, fabricated and installed at TIFR. The pressure and flow rate in the loop is controlled by mass flow controllers and pressure transmitters. The performance and integrity of RPCs in the pilot experimental set up is being monitored to assess the effect of periodic fluctuation and transients in atmospheric pressure and temperature, room pressure variation, flow pulsations, uniformity of gas distribution and power failures. The capability of closed loop gas recirculation system to respond to these changes is also studied. The conclusions from the above experiment are presented. The validations of the first design considerations and subsequent modifications have provided improved guidelines for the future design of the engineering module gas system.

STATYBINIŲ MEDŽIAGŲ KONKURENCINGUMAS IR TENDENCIJOS

OpenAIRE

Kontrimas, Robertas

2010-01-01

Darbe analizuojamas statybinių medžiagų konkurencingumas, nustatyti statybinių medžiagų konkurencingumą įtakojantys veiksniai ir pateikti pasiūlymai rinkos gerinimui. Pasitvirtino hipotezė, kad statybinių medžiagų paklausą ir kainas įtakoja klientų poreikiai ir jų finansinės galimybės, tačiau pasaulinės krizės įtaka yra labai ženkli,. Atlikta darbuotojų ir pirkėjų apklausa padėjo nustatyti, kokios statybinės medžiagos dažniausiai yra perkamos, kaip klientai ir darbuotojai vertina įmonę ir jos...

Multiple Flow Loop SCADA System Implemented on the Production Prototype Loop

Energy Technology Data Exchange (ETDEWEB)

Baily, Scott A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wheat, Robert Mitchell [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-11-16

The following report covers FY 15 activities to develop supervisory control and data acquisition (SCADA) system for the Northstar Moly99 production prototype gas flow loop. The goal of this effort is to expand the existing system to include a second flow loop with a larger production-sized blower. Besides testing the larger blower, this system will demonstrate the scalability of our solution to multiple flow loops.

Consistent momentum space regularization/renormalization of supersymmetric quantum field theories: the three-loop β-function for the Wess-Zumino model

International Nuclear Information System (INIS)

Carneiro, David; Sampaio, Marcos; Nemes, Maria Carolina; Scarpelli, Antonio Paulo Baeta

2003-01-01

We compute the three loop β function of the Wess-Zumino model to motivate implicit regularization (IR) as a consistent and practical momentum-space framework to study supersymmetric quantum field theories. In this framework which works essentially in the physical dimension of the theory we show that ultraviolet are clearly disentangled from infrared divergences. We obtain consistent results which motivate the method as a good choice to study supersymmetry anomalies in quantum field theories. (author)

Performance of Water Recirculation Loop Maintentance Components for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Rector, Tony; Peyton, Barbara; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2014-01-01

Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessonslearned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Performance of Water Recirculation Loop Maintenance Components for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin

2014-01-01

Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Discrimination of Chinese Sauce liquor using FT-IR and two-dimensional correlation IR spectroscopy

Science.gov (United States)

Sun, Su-Qin; Li, Chang-Wen; Wei, Ji-Ping; Zhou, Qun; Noda, Isao

2006-11-01

We applied the three-step IR macro-fingerprint identification method to obtain the IR characteristic fingerprints of so-called Chinese Sauce liquor (Moutai liquor and Kinsly liquor) and a counterfeit Moutai. These fingerprints can be used for the identification and discrimination of similar liquor products. The comparison of their conventional IR spectra, as the first step of identification, shows that the primary difference in Sauce liquor is the intensity of characteristic peaks at 1592 and 1225 cm -1. The comparison of the second derivative IR spectra, as the second step of identification, shows that the characteristic absorption in 1400-1800 cm -1 is substantially different. The comparison of 2D-IR correlation spectra, as the third and final step of identification, can discriminate the liquors from another direction. Furthermore, the method was successfully applied to the discrimination of a counterfeit Moutai from the genuine Sauce liquor. The success of the three-step IR macro-fingerprint identification to provide a rapid and effective method for the identification of Chinese liquor suggests the potential extension of this technique to the identification and discrimination of other wine and spirits, as well.

On loop extensions and cohomology of loops

OpenAIRE

Benítez, Rolando Jiménez; Meléndez, Quitzeh Morales

2015-01-01

In this paper are defined cohomology-like groups that classify loop extensions satisfying a given identity in three variables for association identities, and in two variables for the case of commutativity. It is considered a large amount of identities. This groups generalize those defined in works of Nishigori [2] and of Jhonson and Leedham-Green [4]. It is computed the number of metacyclic extensions for trivial action of the quotient on the kernel in one particular case for left Bol loops a...

OncomiR addiction is generated by a miR-155 feedback loop in Theileria-transformed leukocytes.

Directory of Open Access Journals (Sweden)

Justine Marsolier

Full Text Available The intracellular parasite Theileria is the only eukaryote known to transform its mammalian host cells. We investigated the host mechanisms involved in parasite-induced transformation phenotypes. Tumour progression is a multistep process, yet 'oncogene addiction' implies that cancer cell growth and survival can be impaired by inactivating a single gene, offering a rationale for targeted molecular therapies. Furthermore, feedback loops often act as key regulatory hubs in tumorigenesis. We searched for microRNAs involved in addiction to regulatory loops in leukocytes infected with Theileria parasites. We show that Theileria transformation involves induction of the host bovine oncomiR miR-155, via the c-Jun transcription factor and AP-1 activity. We identified a novel miR-155 target, DET1, an evolutionarily-conserved factor involved in c-Jun ubiquitination. We show that miR-155 expression led to repression of DET1 protein, causing stabilization of c-Jun and driving the promoter activity of the BIC transcript containing miR-155. This positive feedback loop is critical to maintain the growth and survival of Theileria-infected leukocytes; transformation is reversed by inhibiting AP-1 activity or miR-155 expression. This is the first demonstration that Theileria parasites induce the expression of host non-coding RNAs and highlights the importance of a novel feedback loop in maintaining the proliferative phenotypes induced upon parasite infection. Hence, parasite infection drives epigenetic rewiring of the regulatory circuitry of host leukocytes, placing miR-155 at the crossroads between infection, regulatory circuits and transformation.

The Introduction of an Undergraduate Interventional Radiology (IR) Curriculum: Impact on Medical Student Knowledge and Interest in IR

International Nuclear Information System (INIS)

Shaikh, M.; Shaygi, B.; Asadi, H.; Thanaratnam, P.; Pennycooke, K.; Mirza, M.; Lee, M.

2016-01-01

IntroductionInterventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.MethodsIn 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.ResultsSeventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.ConclusionDelivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.

The Introduction of an Undergraduate Interventional Radiology (IR) Curriculum: Impact on Medical Student Knowledge and Interest in IR

Energy Technology Data Exchange (ETDEWEB)

Shaikh, M. [Bradford Royal Infirmary, Department of Radiology, Bradford Teaching Hospital Foundation Trust (United Kingdom); Shaygi, B. [Royal Devon and Exeter Hospital, Interventional Radiology Department (United Kingdom); Asadi, H., E-mail: asadi.hamed@gmail.com; Thanaratnam, P.; Pennycooke, K.; Mirza, M.; Lee, M., E-mail: mlee@rcsi.ie [Beaumont Hospital, Interventional Radiology Service, Department of Radiology (Ireland)

2016-04-15

IntroductionInterventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.MethodsIn 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.ResultsSeventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.ConclusionDelivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.

Ion beam synthesis of IrSi3 by implantation of 2 MeV Ir ions

International Nuclear Information System (INIS)

Sjoreen, T.P.; Chisholm, M.F.; Hinneberg, H.J.

1992-11-01

Formation of a buried IrSi 3 layer in (111) oriented Si by ion implantation and annealing has been studied at an implantation energy of 2 MeV for substrate temperatures of 450--550C. Rutherford backscattering (RBS), ion channeling and cross-sectional transmission electron microscopy showed that a buried epitaxial IrSi 3 layer is produced at 550C by implanting ≥ 3.4 x 10 17 Ir/cm 2 and subsequently annealing for 1 h at 1000C plus 5 h at 1100C. At a dose of 3.4 x 10 17 Ir/cm 2 , the thickness of the layer varied between 120 and 190 nm and many large IrSi 3 precipitates were present above and below the film. Increasing the dose to 4.4 x 10 17 Ir/cm 2 improved the layer uniformity at the expense of increased lattice damage in the overlying Si. RBS analysis of layer formation as a function of substrate temperature revealed the competition between the mechanisms for optimizing surface crystallinity vs. IrSi 3 layer formation. Little apparent substrate temperature dependence was evident in the as-implanted state but after annealing the crystallinity of the top Si layer was observed to deteriorate with increasing substrate temperature while the precipitate coarsening and coalescence improved

Rapid Simulation of Flat Knitting Loops Based On the Yarn Texture and Loop Geometrical Model

Directory of Open Access Journals (Sweden)

Lu Zhiwen

2017-06-01

Full Text Available In order to create realistic loop primitives suitable for the fast computer-aided design (CAD of the flat knitted fabric, we have a research on the geometric model of the loop as well as the variation of the loop surface. Establish the texture variation model based on the changing process from the normal yarn to loop that provides the realistic texture of the simulative loop. Then optimize the simulative loop based on illumination variation. This paper develops the computer program with the optimization algorithm and achieves the loop simulation of different yarns to verify the feasibility of the proposed algorithm. Our work provides a fast CAD of the flat knitted fabric with loop simulation, and it is not only more realistic but also material adjustable. Meanwhile it also provides theoretical value for the flat knitted fabric computer simulation.

Smulkaus ir vidutinio verslo konkurencingumas Lietuvoje

OpenAIRE

Vijeikis, Juozas; Makštutis, Antanas

2009-01-01

Straipsnio mokslinė problema, naujumas ir aktualumas. Konkurencingumas kaip įmonių efektyvios veiklos reiškinys yra aktualus šalies verslo gyvenime vykdant darnios ekonominės plėtros politiką. Ši politika kaip problema smulkaus ir vidutinio verslo (SVV) plėtrai ir konkurencingumui didinti nėra sistemiškai ištirta ir aprašyta Lietuvos sąlygomis mokslinėje ir praktinėje literatūroje. Vienas svarbiausių veiksnių, siekiant spartaus ekonominio augimo, yra darnios verslininkystės plėtra Lietuvoje n...

Structural, phase stability, electronic, elastic properties and hardness of IrN{sub 2} and zinc blende IrN: First-principles calculations

Energy Technology Data Exchange (ETDEWEB)

Zhou, Zhaobo [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhou, Xiaolong, E-mail: kmzxlong@163.com [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhang, Kunhua [State Key Laboratory of Rare Precious Metals Comprehensive Utilization of New Technologies, Kunming Institute of Precious Metals, Kunming 650106 (China)

2016-12-15

First-principle calculations were performed to investigate the structural, phase stability, electronic, elastic properties and hardness of monoclinic structure IrN{sub 2} (m-IrN{sub 2}), orthorhombic structure IrN{sub 2} (o-IrN{sub 2}) and zinc blende structure IrN (ZB IrN). The results show us that only m-IrN{sub 2} is both thermodynamic and dynamic stability. The calculated band structure and density of states (DOS) curves indicate that o-IrN{sub 2} and ZB Ir-N compounds we calculated have metallic behavior while m-IrN{sub 2} has a small band gap of ~0.3 eV, and exist a common hybridization between Ir-5d and N-2p states, which forming covalent bonding between Ir and N atoms. The difference charge density reveals the electron transfer from Ir atom to N atom for three Ir-N compounds, which forming strong directional covalent bonds. Notable, a strong N-N bond appeared in m-IrN{sub 2} and o-IrN{sub 2}. The ratio of bulk to shear modulus (B/G) indicate that three Ir-N compounds we calculated are ductile, and ZB IrN possesses a better ductility than two types IrN{sub 2}. m-IrN{sub 2} has highest Debye temperature (736 K), illustrating it possesses strongest covalent bonding. The hardness of three Ir-N compounds were also calculated, and the results reveal that m-IrN{sub 2} (18.23 GPa) and o-IrN{sub 2} (18.02 GPa) are ultraincompressible while ZB IrN has a negative value, which may be attributed to phase transition at ca. 1.98 GPa.

Protection of p+-n-Si Photoanodes by Sputter-Deposited Ir/IrOxThin Films

DEFF Research Database (Denmark)

Mei, Bastian Timo; Seger, Brian; Pedersen, Thomas

2014-01-01

Sputter deposition of Ir/IrOx on p+-n-Si without interfacial corrosion protection layers yielded photoanodes capable of efficient water oxidation (OER) in acidic media (1 M H2SO4). Stability of at least 18 h was shown by chronoamperomety at 1.23 V versus RHE (reversible hydrogen electrode) under 38...... density of 1 mA/cm2 at 1.05 V vs. RHE. Further improvement by heat treatment resulted in a cathodic shift of 40 mV and enabled a current density of 10 mA/cm2 (requirements for a 10% efficient tandem device) at 1.12 V vs. RHS under irradiation. Thus, the simple IrOx/Ir/p+-n-Si structures not only provide...

Novel cross-talk between IGF-IR and DDR1 regulates IGF-IR trafficking, signaling and biological responses

Science.gov (United States)

Sacco, Antonella; Morcavallo, Alaide; Vella, Veronica; Voci, Concetta; Spatuzza, Michela; Xu, Shi-Qiong; Iozzo, Renato V.; Vigneri, Riccardo; Morrione, Andrea; Belfiore, Antonino

2015-01-01

The insulin-like growth factor-I receptor (IGF-IR), plays a key role in regulating mammalian development and growth, and is frequently deregulated in cancer contributing to tumor initiation and progression. Discoidin domain receptor 1 (DDR1), a collagen receptor tyrosine-kinase, is as well frequently overexpressed in cancer and implicated in cancer progression. Thus, we investigated whether a functional cross-talk between the IGF-IR and DDR1 exists and plays any role in cancer progression. Using human breast cancer cells we found that DDR1 constitutively associated with the IGF-IR. However, this interaction was enhanced by IGF-I stimulation, which promoted rapid DDR1 tyrosine-phosphorylation and co-internalization with the IGF-IR. Significantly, DDR1 was critical for IGF-IR endocytosis and trafficking into early endosomes, IGF-IR protein expression and IGF-I intracellular signaling and biological effects, including cell proliferation, migration and colony formation. These biological responses were inhibited by DDR1 silencing and enhanced by DDR1 overexpression. Experiments in mouse fibroblasts co-transfected with the human IGF-IR and DDR1 gave similar results and indicated that, in the absence of IGF-IR, collagen-dependent phosphorylation of DDR1 is impaired. These results demonstrate a critical role of DDR1 in the regulation of IGF-IR action, and identify DDR1 as a novel important target for breast cancers that overexpress IGF-IR. PMID:25840417

Multi-loop PWR modeling and hardware-in-the-loop testing using ACSL

International Nuclear Information System (INIS)

Thomas, V.M.; Heibel, M.D.; Catullo, W.J.

1989-01-01

Westinghouse has developed an Advanced Digital Feedwater Control System (ADFCS) which is aimed at reducing feedwater related reactor trips through improved control performance for pressurized water reactor (PWR) power plants. To support control system setpoint studies and functional design efforts for the ADFCS, an ACSL based model of the nuclear steam supply system (NSSS) of a Westinghouse (PWR) was generated. Use of this plant model has been extended from system design to system testing through integration of the model into a Hardware-in-Loop test environment for the ADFCS. This integration includes appropriate interfacing between a Gould SEL 32/87 computer, upon which the plant model executes in real time, and the Westinghouse Distributed Processing family (WDPF) test hardware. A development program has been undertaken to expand the existing ACSL model to include capability to explicitly model multiple plant loops, steam generators, and corresponding feedwater systems. Furthermore, the program expands the ADFCS Hardware-in-Loop testing to include the multi-loop plant model. This paper provides an overview of the testing approach utilized for the ADFCS with focus on the role of Hardware-in-Loop testing. Background on the plant model, methodology and test environment is also provided. Finally, an overview is presented of the program to expand the model and associated Hardware-in-Loop test environment to handle multiple loops

Design strategies for dynamic closed-loop optogenetic neurocontrol in vivo

Science.gov (United States)

Bolus, M. F.; Willats, A. A.; Whitmire, C. J.; Rozell, C. J.; Stanley, G. B.

2018-04-01

Objective. Controlling neural activity enables the possibility of manipulating sensory perception, cognitive processes, and body movement, in addition to providing a powerful framework for functionally disentangling the neural circuits that underlie these complex phenomena. Over the last decade, optogenetic stimulation has become an increasingly important and powerful tool for understanding neural circuit function, owing to the ability to target specific cell types and bidirectionally modulate neural activity. To date, most stimulation has been provided in open-loop or in an on/off closed-loop fashion, where previously-determined stimulation is triggered by an event. Here, we describe and demonstrate a design approach for precise optogenetic control of neuronal firing rate modulation using feedback to guide stimulation continuously. Approach. Using the rodent somatosensory thalamus as an experimental testbed for realizing desired time-varying patterns of firing rate modulation, we utilized a moving average exponential filter to estimate firing rate online from single-unit spiking measured extracellularly. This estimate of instantaneous rate served as feedback for a proportional integral (PI) controller, which was designed during the experiment based on a linear-nonlinear Poisson (LNP) model of the neuronal response to light. Main results. The LNP model fit during the experiment enabled robust closed-loop control, resulting in good tracking of sinusoidal and non-sinusoidal targets, and rejection of unmeasured disturbances. Closed-loop control also enabled manipulation of trial-to-trial variability. Significance. Because neuroscientists are faced with the challenge of dissecting the functions of circuit components, the ability to maintain control of a region of interest in spite of changes in ongoing neural activity will be important for disambiguating function within networks. Closed-loop stimulation strategies are ideal for control that is robust to such changes

Random walk loop soup

OpenAIRE

Lawler, Gregory F.; Ferreras, José A. Trujillo

2004-01-01

The Brownian loop soup introduced in Lawler and Werner (2004) is a Poissonian realization from a sigma-finite measure on unrooted loops. This measure satisfies both conformal invariance and a restriction property. In this paper, we define a random walk loop soup and show that it converges to the Brownian loop soup. In fact, we give a strong approximation result making use of the strong approximation result of Koml\\'os, Major, and Tusn\\'ady. To make the paper self-contained, we include a proof...

Comparison of air-kerma strength determinations for HDR 192Ir sources

International Nuclear Information System (INIS)

Rasmussen, Brian E.; Davis, Stephen D.; Schmidt, Cal R.; Micka, John A.; DeWerd, Larry A.

2011-01-01

Purpose: To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) 192 Ir brachytherapy sources maintained by University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. Methods: The improved, laser-aligned seven-distance apparatus of University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR 192 Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the 192 Ir air-kerma calibration coefficient from the NIST air-kerma standards at 137 Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A wall for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. Results: The average measurements when using the inverse N K interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Conclusions: Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well chambers was 0.01%, confirming that

Comparison of air-kerma strength determinations for HDR (192)Ir sources.

Science.gov (United States)

Rasmussen, Brian E; Davis, Stephen D; Schmidt, Cal R; Micka, John A; Dewerd, Larry A

2011-12-01

To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) (192)Ir brachytherapy sources maintained by the University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. The improved, laser-aligned seven-distance apparatus of the University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR (192)Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the (192)Ir air-kerma calibration coefficient from the NIST air-kerma standards at (137)Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A(wall) for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. The average measurements when using the inverse N(K) interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well chambers was 0.01%, confirming that it is not necessary to

Neutron transport in irradiation loops (IRENE loop)

International Nuclear Information System (INIS)

Sarsam, Maher.

1980-09-01

This thesis is composed of two parts with different aspects. Part one is a technical description of the loop and its main ancillary facilities as well as of the safety and operational regulations. The measurement methods on the model of the ISIS reactor and on the loop in the OSIRIS reactor are described. Part two deals with the possibility of calculating the powers dissipated by each rod of the fuel cluster, using appropriate computer codes, not only in the reflector but also in the core and to suggest a method of calculation [fr

HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome: Brazilian Metabolic Syndrome Study (BRAMS).

Science.gov (United States)

Geloneze, Bruno; Vasques, Ana Carolina Junqueira; Stabe, Christiane França Camargo; Pareja, José Carlos; Rosado, Lina Enriqueta Frandsen Paez de Lima; Queiroz, Elaine Cristina de; Tambascia, Marcos Antonio

2009-03-01

To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 90th percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. In the healthy group, HOMA-IR indexes were associated with central obesity, triglycerides and total cholesterol (p 2.7 and HOMA2-IR > 1.8; and, for MS were: HOMA1-IR > 2.3 (sensitivity: 76.8%; specificity: 66.7%) and HOMA2-IR > 1.4 (sensitivity: 79.2%; specificity: 61.2%). The cut-off values identified for HOMA1-IR and HOMA2-IR indexes have a clinical and epidemiological application for identifying IR and MS in Westernized admixtured multi-ethnic populations.

IOT Overview: IR Instruments

Science.gov (United States)

Mason, E.

In this instrument review chapter the calibration plans of ESO IR instruments are presented and briefly reviewed focusing, in particular, on the case of ISAAC, which has been the first IR instrument at VLT and whose calibration plan served as prototype for the coming instruments.

Atom condensation on an atomically smooth surface: Ir, Re, W, and Pd on Ir(111)

International Nuclear Information System (INIS)

Wang, S.C.; Ehrlich, G.

1991-01-01

The distribution of condensing metal atoms over the two types of sites present on an atomically smooth Ir(111) has been measured in a field ion microscope. For Ir, Re, W, and Pd from a thermal source, condensing on Ir(111) at ∼20 K, the atoms are randomly distributed, as expected if they condense at the first site struck

Single-nucleotide polymorphism of INS, INSR, IRS1, IRS2, PPAR-G ...

Indian Academy of Sciences (India)

2017-03-02

Mar 2, 2017 ... Abstract. Polycystic ovary syndrome (PCOS) is the most common and a complex female endocrine disorder, and is one of the leading cause of female infertility. Here, we aimed to investigate the association of single-nucleotide polymorphism of INS, INSR,. IRS1, IRS2, PPAR-G and CAPN10 gene in the ...

Suppression of superconductivity in Nb by IrMn in IrMn/Nb bilayers

KAUST Repository

Wu, B. L.; Yang, Y. M.; Guo, Z. B.; Wu, Y. H.; Qiu, J. J.

2013-01-01

Effect of antiferromagnet on superconductivity has been investigated in IrMn/Nb bilayers. Significant suppression of both transition temperature (Tc) and lower critical field (Hc1) of Nb is found in IrMn/Nb bilayers as compared to a single layer Nb

Loop space representation of quantum general relativity and the group of loops

International Nuclear Information System (INIS)

Gambini, R.

1991-01-01

The action of the constraints of quantum general relativity on a general state in the loop representation is coded in terms of loop derivatives. These differential operators are related to the infinitesimal generators of the group of loops and generalize the area derivative first considered by Mandelstam. A new sector of solutions of the physical states space of nonperturbative quantum general relativity is found. (orig.)

Fermions and loops on graphs: I. Loop calculus for determinants

International Nuclear Information System (INIS)

Chernyak, Vladimir Y; Chertkov, Michael

2008-01-01

This paper is the first in a series devoted to evaluation of the partition function in statistical models on graphs with loops in terms of the Berezin/fermion integrals. The paper focuses on a representation of the determinant of a square matrix in terms of a finite series, where each term corresponds to a loop on the graph. The representation is based on a fermion version of the loop calculus, previously introduced by the authors for graphical models with finite alphabets. Our construction contains two levels. First, we represent the determinant in terms of an integral over anti-commuting Grassmann variables, with some reparametrization/gauge freedom hidden in the formulation. Second, we show that a special choice of the gauge, called the BP (Bethe–Peierls or belief propagation) gauge, yields the desired loop representation. The set of gauge fixing BP conditions is equivalent to the Gaussian BP equations, discussed in the past as efficient (linear scaling) heuristics for estimating the covariance of a sparse positive matrix

On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

Science.gov (United States)

Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

2013-10-01

The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH3)4][IrCl6] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.

On formation mechanism of Pd–Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

International Nuclear Information System (INIS)

Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

2013-01-01

The formation mechanism of Pd–Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH 3 ) 4 ][IrCl 6 ] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd–Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10–200 nm) and dendrite Ir-rich (10–50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd–Ir nanoparticles, were found to occur.Graphical Abstract

Dechanneling by dislocation loops

International Nuclear Information System (INIS)

Chalant, Gerard.

1976-09-01

Ion implantation always induces the creation of dislocation loops. When the damage profile is determined by a backscattering technique, the dechanneling by these loops is implicitely at the origin of these measurements. The dechanneling of alpha particles by dislocation loops produced by the coalescence of quenched-in vacancies in aluminium is studied. The dechanneling and the concentration of loops were determined simultaneously. The dechanneling width around dislocation was found equal to lambda=6A, both for perfect and imperfect loops having a mean diameter d=250A. In the latter case, a dechanneling probability chi=0.34 was determined for the stacking fault, in good agreement with previous determination in gold. A general formula is proposed which takes into account the variation of lambda with the curvature (or the diameter d) of the loops. Finally, by a series of isothermal anneals, the self-diffusion energy ΔH of aluminium was measured. The value obtained ΔH=1.32+-0.10eV is in good agreement with the values obtained by other methods [fr

Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action

DEFF Research Database (Denmark)

Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob

2018-01-01

Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling...... properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type......, IRS-1-/-and IRS-2-/-mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1...

The Brownian loop soup

OpenAIRE

Lawler, Gregory F.; Werner, Wendelin

2003-01-01

We define a natural conformally invariant measure on unrooted Brownian loops in the plane and study some of its properties. We relate this measure to a measure on loops rooted at a boundary point of a domain and show how this relation gives a way to ``chronologically add Brownian loops'' to simple curves in the plane.

Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action.

Science.gov (United States)

Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob; Kahn, C Ronald; Emanuelli, Brice

2018-07-01

Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type, IRS-1 -/- and IRS-2 -/- mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1. These regulated sites included previously reported substrates of the insulin/IGF-1 signalling pathway, as well as novel substrates including Nuclear Factor I X and Semaphorin-4B. In silico prediction suggests the protein kinase B (PKB), protein kinase C (PKC), and cyclin-dependent kinase (CDK) as the main mediators of these phosphorylation events. Importantly, we found preferential phosphorylation patterns depending on the presence of either IRS-1 or IRS-2, which was associated with specific sets of kinases involved in signal transduction downstream of these substrates such as PDHK1, MAPK3, and PKD1 for IRS-1, and PIN1 and PKC beta for IRS-2. Overall, by generating a comprehensive phosphoproteomic profile from brown preadipocyte cells in response to IGF-1 stimulation, we reveal both common and distinct insulin/IGF-1 signalling events mediated by specific IRS proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

Effect of ambient pressure variation on closed loop gas system for India based Neutrino Observatory (INO)

Science.gov (United States)

Satyanarayana, B.; Majumder, G.; Mondal, N. K.; Kalmani, S. D.; Shinde, R. R.; Joshi, A.

2014-10-01

Pilot unit of a closed loop gas mixing and distribution system for the INO project was designed and is being operated with 1.8meters × 1.9meters RPCs for about two years. A number of studies on controlling the flow and optimisation of the gas mixture through the RPC stack were carried out during this period. The gas system essentially measures and attempts to maintain absolute pressure inside the RPC gas volume. During typical Mumbai monsoon seasons, the barometric pressure changes rather rapidly, due to which the gas system fails to maintain the set differential pressure between the ambience and the RPC gas volume. As the safety bubblers on the RPC gas input lines are set to work on fixed pressure differentials, the ambient pressure changes lead to either venting out and thus wasting gas through safety bubblers or over pressuring the RPCs gas volume and thus degrading its performance. The above problem also leads to gas mixture contamination through minute leaks in gas gap. The problem stated above was solved by including the ambient barometric pressure as an input parameter in the closed loop. Using this, it is now possible to maintain any set differential pressure between the ambience and RPC gas volumes between 0 to 20mm of water column, thus always ensuring a positive pressure inside the RPC gas volume with respect to the ambience. This has resulted in improved performance of the gas system by maintaining the constant gas flow and reducing the gas toping up frequency. In this paper, we will highlight the design features and improvements of the closed loop gas system. We will present some of the performance studies and considerations for scaling up the system to be used with the engineering module and then followed by Iron Calorimeter detector (ICAL), which is designed to deploy about 30,000 RPCs of 1.8meters × 1.9 meters in area.

Reactor recirculation pump test loop

International Nuclear Information System (INIS)

Taka, Shusei; Kato, Hiroyuki

1979-01-01

A test loop for a reactor primary loop recirculation pumps (PLR pumps) has been constructed at Ebara's Haneda Plant in preparation for production of PLR pumps under license from Byron Jackson Pump Division of Borg-Warner Corporation. This loop can simulate operating conditions for test PLR pumps with 130 per cent of the capacity of pumps for a 1100 MWe BWR plant. A main loop, primary cooling system, water demineralizer, secondary cooling system, instrumentation and control equipment and an electric power supply system make up the test loop. This article describes the test loop itself and test results of two PLR pumps for Fukushima No. 2 N.P.S. Unit 1 and one main circulation pump for HAZ Demonstration Test Facility. (author)

Engineering challenges and solutions for the ITER magnetic diagnostics flux loops

International Nuclear Information System (INIS)

Clough, M.; Casal, N.; Suarez Diaz, A.; Vayakis, G.; Walsh, M.

2014-01-01

The Magnetic Diagnostics Flux Loops (MDFL) are a key diagnostic for the ITER tokamak, providing important information about the shape of the plasma boundary, instabilities and magnetic error fields. In total, 237 flux loops will be installed on ITER, on the inside and outside walls of the Vacuum Vessel, and will range in area from 1 m 2 to 250 m 2 . This paper describes the detailed engineering design of the MDFL, explaining the solutions developed to maintain measurement accuracy within their difficult operating environment and other requirements: ultra-high vacuum conditions, strong magnetic fields, high gamma and neutron radiation doses, challenging installation, very high reliability and no maintenance during the 20 year machine lifetime. In addition, the paper discusses testing work undertaken to validate the design and outlines the remaining tasks to be performed. The views and opinions expressed herein do not necessarily reflect those of the ITER Organization. (authors)

Wilson loops in minimal surfaces

International Nuclear Information System (INIS)

Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

1999-01-01

The AdS/CFT correspondence suggests that the Wilson loop of the large N gauge theory with N = 4 supersymmetry in 4 dimensions is described by a minimal surface in AdS 5 x S 5 . The authors examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which the authors call BPS loops, whose expectation values are free from ultra-violet divergence. They formulate the loop equation for such loops. To the extent that they have checked, the minimal surface in AdS 5 x S 5 gives a solution of the equation. The authors also discuss the zig-zag symmetry of the loop operator. In the N = 4 gauge theory, they expect the zig-zag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. They will show how this is realized for the minimal surface

Wilson loops and minimal surfaces

International Nuclear Information System (INIS)

Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

1999-01-01

The AdS-CFT correspondence suggests that the Wilson loop of the large N gauge theory with N=4 supersymmetry in four dimensions is described by a minimal surface in AdS 5 xS 5 . We examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which we call BPS loops, whose expectation values are free from ultraviolet divergence. We formulate the loop equation for such loops. To the extent that we have checked, the minimal surface in AdS 5 xS 5 gives a solution of the equation. We also discuss the zigzag symmetry of the loop operator. In the N=4 gauge theory, we expect the zigzag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. We will show how this is realized for the minimal surface. (c) 1999 The American Physical Society

Density functional study of the L10-αIrV transition in IrV and RhV

International Nuclear Information System (INIS)

Mehl, Michael J.; Hart, Gus L.W.; Curtarolo, Stefano

2011-01-01

Research highlights: → The computational determination of the ground state of a material can be a difficult task, particularly if the ground state is uncommon and so not found in usual databases. In this paper we consider the alpha-IrV structure, a low temperature structure found only in two compounds, IrV and RhV. In both cases this structure can be considered as a distorted tetragonal structure, and the tetragonal 'L1 0 ' structure is the high temperature structure for both compounds. We show, however, that the logical path for the transition from the L1 0 to the alpha-IrV structure is energetically forbidden, and find a series of unstable and metastable structures which have a lower energy than the L1 0 phase, but are higher in energy than the alpha-IrV phase. We also consider the possibility of the alpha-IrV structure appearing in neighboring compounds. We find that both IrTi and RhTi are candidates. - Abstract: Both IrV and RhV crystallize in the αIrV structure, with a transition to the higher symmetry L1 0 structure at high temperature, or with the addition of excess Ir or Rh. Here we present evidence that this transition is driven by the lowering of the electronic density of states at the Fermi level of the αIrV structure. The transition has long been thought to be second order, with a simple doubling of the L1 0 unit cell due to an unstable phonon at the R point (0 1/2 1/2). We use first-principles calculations to show that all phonons at the R point are, in fact, stable, but do find a region of reciprocal space where the L1 0 structure has unstable (imaginary frequency) phonons. We use the frozen phonon method to examine two of these modes, relaxing the structures associated with the unstable phonon modes to obtain new structures which are lower in energy than L1 0 but still above αIrV. We examine the phonon spectra of these structures as well, looking for instabilities, and find further instabilities, and more relaxed structures, all of which have

Protein loop modeling using a new hybrid energy function and its application to modeling in inaccurate structural environments.

Directory of Open Access Journals (Sweden)

Hahnbeom Park

Full Text Available Protein loop modeling is a tool for predicting protein local structures of particular interest, providing opportunities for applications involving protein structure prediction and de novo protein design. Until recently, the majority of loop modeling methods have been developed and tested by reconstructing loops in frameworks of experimentally resolved structures. In many practical applications, however, the protein loops to be modeled are located in inaccurate structural environments. These include loops in model structures, low-resolution experimental structures, or experimental structures of different functional forms. Accordingly, discrepancies in the accuracy of the structural environment assumed in development of the method and that in practical applications present additional challenges to modern loop modeling methods. This study demonstrates a new strategy for employing a hybrid energy function combining physics-based and knowledge-based components to help tackle this challenge. The hybrid energy function is designed to combine the strengths of each energy component, simultaneously maintaining accurate loop structure prediction in a high-resolution framework structure and tolerating minor environmental errors in low-resolution structures. A loop modeling method based on global optimization of this new energy function is tested on loop targets situated in different levels of environmental errors, ranging from experimental structures to structures perturbed in backbone as well as side chains and template-based model structures. The new method performs comparably to force field-based approaches in loop reconstruction in crystal structures and better in loop prediction in inaccurate framework structures. This result suggests that higher-accuracy predictions would be possible for a broader range of applications. The web server for this method is available at http://galaxy.seoklab.org/loop with the PS2 option for the scoring function.

PENDIDIKAN AKHLAK MUSLIMAT MELALUISYA’IR : ANALISIS GENDER ATAS AJARAN SYI’IR MUSLIMAT KARYA NYAI WANIFAH KUDUS

Directory of Open Access Journals (Sweden)

Nur Said

2016-03-01

Full Text Available Penelitian ini difokuskan pada tiga hal: (1 Apakah karakteristik lingkup isi Syi’ir Muslimat?, (2 Bagai-manakah kondisi sosial budaya pada saat naskah ditulis oleh penulis?, (3 Apa nilai-nilai pendidikan moral bagi perempuan Muslim di isi Syi’ir Muslimat dalam perspektif gender?. Penelitian ini menggunakan pendekatan filologi dengan meningkatkan penggunaan analisis gender. Hasil dari penelitian ini adalah: Pertama, Syi’ir Muslimat ditulis oleh Nyai Wanifah, seorang wanita yang hidup pada zaman kolonial Belanda dipesantren tradisi di Kudus, Jawa Tengah. Kedua, beberapa nilai pendidikan moral di Syi’ir Muslimatantara lain: (1 Pentingnya pendidikan moral, (2 Bahaya perempuan bodoh; (3 Pentingnya belajar bagi perempuan di usia dini, (4 Etika menghias diri; (5 Bahaya materialisme, (6 Etika hubungan keluarga; (7 Dari rumah untuk mencapai surga; (8 Berhati-hatilah dengan tipu iblis; (9 Hindari perzinahan; (10 yang penting dari penutupan aurot; (11 yang ditujukan kepada orang tua. Ketiga, meskipun ada beberapa senyawa yang bias gender dalam Syi’ir Muslimat misalnya: (a Ada penjelasan yang menunjukkan bahwa perempuan lebih rendah dibandingkan laki-laki dalam derajat, (2 Pernyataan bahwa wanita bicara dibandingkan laki-laki, (3 wanita hanya cocok di wilayah domestik; Namun secara umum nasihat di syi’ir masih sangat relafen dalam konteks sekarang, terutama untuk memberikan solusi alternatif dalam merespon krisis moral bangsa terutama pada wanita generasi muda. Kata kunci: Syi’ir Muslimat, Pendidikan Karakter, Analisis Gender. This study focused on three things: (1 What is the characteristics of the scope of contents of Syi’ir Muslimat?, (2 What is the socio-cultural conditions at the time the manuscript was written by the author?, (3 What are the moral education values for Muslim women in the content of Syi’ir Muslimat in the perspective of gender?. This research uses a philological approach with enhanced use of gender analysis. The

BPS Wilson loops and Bremsstrahlung function in ABJ(M): a two loop analysis

Energy Technology Data Exchange (ETDEWEB)

Bianchi, Marco S. [Institut für Physik, Humboldt-Universität zu Berlin,Newtonstraße 15, 12489 Berlin (Germany); Griguolo, Luca [Dipartimento di Fisica e Scienze della Terra, Università di Parmaand INFN Gruppo Collegato di Parma,Viale G.P. Usberti 7/A, 43100 Parma (Italy); Leoni, Matias [Physics Department, FCEyN-UBA & IFIBA-CONICETCiudad Universitaria, Pabellón I, 1428, Buenos Aires (Argentina); Penati, Silvia [Dipartimento di Fisica, Università di Milano-Bicoccaand INFN, Sezione di Milano-Bicocca,Piazza della Scienza 3, I-20126 Milano (Italy); Seminara, Domenico [Dipartimento di Fisica, Università di Firenzeand INFN Sezione di Firenze,via G. Sansone 1, 50019 Sesto Fiorentino (Italy)

2014-06-19

We study a family of circular BPS Wilson loops in N=6 super Chern-Simons-matter theories, generalizing the usual 1/2-BPS circle. The scalar and fermionic couplings depend on two deformation parameters and these operators can be considered as the ABJ(M) counterpart of the DGRT latitudes defined in N=4 SYM. We perform a complete two-loop analysis of their vacuum expectation value, discuss the appearance of framing-like phases and propose a general relation with cohomologically equivalent bosonic operators. We make an all-loop proposal for computing the Bremsstrahlung function associated to the 1/2-BPS cusp in terms of these generalized Wilson loops. When applied to our two-loop result it reproduces the known expression. Finally, we comment on the generalization of this proposal to the bosonic 1/6-BPS case.

Leaf venation, as a resistor, to optimize a switchable IR absorber.

Science.gov (United States)

Alston, M E; Barber, R

2016-08-24

Leaf vascular patterns are the mechanisms and mechanical support for the transportation of fluidics for photosynthesis and leaf development properties. Vascular hierarchical networks in leaves have far-reaching functions in optimal transport efficiency of functional fluidics. Embedding leaf morphogenesis as a resistor network is significant in the optimization of a translucent thermally functional material. This will enable regulation through pressure equalization by diminishing flow pressure variation. This paper investigates nature's vasculature networks that exhibit hierarchical branching scaling applied to microfluidics. To enable optimum potential for pressure drop regulation by algorithm design. This code analysis of circuit conduit optimization for transport fluidic flow resistance is validated against CFD simulation, within a closed loop network. The paper will propose this self-optimization, characterization by resistance seeking targeting to determine a microfluidic network as a resistor. To advance a thermally function material as a switchable IR absorber.

The IRS-1 signaling system.

Science.gov (United States)

Myers, M G; Sun, X J; White, M F

1994-07-01

Insulin-receptor substrate 1 (IRS-1) is a principal substrate of the receptor tyrosine kinase for insulin and insulin-like growth factor 1, and a substrate for a tyrosine kinase activated by interleukin 4. IRS-1 undergoes multisite tyrosine phosphorylation and mediates downstream signals by 'docking' various proteins that contain Src homology 2 domains. IRS-1 appears to be a unique molecule; however, 4PS, a protein found mainly in hemopoietic cells, may represent another member of this family.

pH Mapping on Tooth Surfaces for Quantitative Caries Diagnosis Using Micro Ir/IrOx pH Sensor.

Science.gov (United States)

Ratanaporncharoen, Chindanai; Tabata, Miyuki; Kitasako, Yuichi; Ikeda, Masaomi; Goda, Tatsuro; Matsumoto, Akira; Tagami, Junji; Miyahara, Yuji

2018-04-03

A quantitative diagnostic method for dental caries would improve oral health, which directly affects the quality of life. Here we describe the preparation and application of Ir/IrOx pH sensors, which are used to measure the surface pH of dental caries. The pH level is used as an indicator to distinguish between active and arrested caries. After a dentist visually inspected and defined 18 extracted dentinal caries at various positions as active or arrested caries, the surface pH values of sound and caries areas were directly measured with an Ir/IrOx pH sensor with a diameter of 300 μm as a dental explorer. The average pH values of the sound root, the arrested caries, and active caries were 6.85, 6.07, and 5.30, respectively. The pH obtained with an Ir/IrOx sensor was highly correlated with the inspection results by the dentist, indicating that the types of caries were successfully categorized. This caries testing technique using a micro Ir/IrOx pH sensor provides an accurate quantitative caries evaluation and has potential in clinical diagnosis.

Closed Loop Control of Penetration Depth during CO₂ Laser Lap Welding Processes

Directory of Open Access Journals (Sweden)

Antonio Ancona

2012-08-01

Full Text Available In this paper we describe a novel spectroscopic closed loop control system capable of stabilizing the penetration depth during laser welding processes by controlling the laser power. Our novel approach is to analyze the optical emission from the laser generated plasma plume above the keyhole, to calculate its electron temperature as a process-monitoring signal. Laser power has been controlled by using a quantitative relationship between the penetration depth and the plasma electron temperature. The sensor is able to correlate in real time the difference between the measured electron temperature and its reference value for the requested penetration depth. Accordingly the closed loop system adjusts the power, thus maintaining the penetration depth.

Computational stability appraisal of rectangular natural circulation loop: Effect of loop inclination

International Nuclear Information System (INIS)

Krishnani, Mayur; Basu, Dipankar N.

2017-01-01

Highlights: • Computational model developed for single-phase rectangular natural circulation loop. • Role of loop inclination to vertical on thermalhydraulic stability is explored. • Inclination has strong stabilizing effect due to lower effective gravitation force. • Increase in tilt angle reduces settling time and highest amplitude of oscillation. • An angle of 15° is suggested for the selected loop geometry. - Abstract: Controlling stability behavior of single-phase natural circulation loops, without significantly affecting its steady-state characteristics, is a topic of wide research interest. Present study explores the role of loop inclination on a particular loop geometry. Accordingly a 3D computational model of a rectangular loop is developed and transient conservation equations are solved to obtain the temporal variation in flow parameters. Starting from the quiescent state, simulations are performed for selected sets of operating conditions and also with a few selected inclination angles. System experiences instability at higher heater powers and also with higher sink temperatures. Inclination is found to have a strong stabilizing influence owing to the reduction in the effective gravitational acceleration and subsequent decline in local buoyancy effects. The settling time and highest amplitude of oscillations substantially reduces for a stable system with a small inclination. Typically-unstable systems can also suppress the oscillations, when subjected to tilting, within a reasonable period of time. It is possible to stabilize the loop within shorter time span by increasing the tilt angle, but at the expense of reduction in steady-state flow rate. Overall a tilt angle of 15° is suggested for the selected geometry. Results from the 3D model is compared with the predictions from an indigenous 1D code. While similar qualitative influence of inclination is observed, the 1D model predicts early appearance of the stability threshold and hence hints

Comparison of air-kerma strength determinations for HDR {sup 192}Ir sources

Energy Technology Data Exchange (ETDEWEB)

Rasmussen, Brian E.; Davis, Stephen D.; Schmidt, Cal R.; Micka, John A.; DeWerd, Larry A. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2011-12-15

Purpose: To perform a comparison of the interim air-kerma strength standard for high dose rate (HDR) {sup 192}Ir brachytherapy sources maintained by University of Wisconsin Accredited Dosimetry Calibration Laboratory (UWADCL) with measurements of the various source models using modified techniques from the literature. The current interim standard was established by Goetsch et al. in 1991 and has remained unchanged to date. Methods: The improved, laser-aligned seven-distance apparatus of University of Wisconsin Medical Radiation Research Center (UWMRRC) was used to perform air-kerma strength measurements of five different HDR {sup 192}Ir source models. The results of these measurements were compared with those from well chambers traceable to the original standard. Alternative methodologies for interpolating the {sup 192}Ir air-kerma calibration coefficient from the NIST air-kerma standards at {sup 137}Cs and 250 kVp x rays (M250) were investigated and intercompared. As part of the interpolation method comparison, the Monte Carlo code EGSnrc was used to calculate updated values of A{sub wall} for the Exradin A3 chamber used for air-kerma strength measurements. The effects of air attenuation and scatter, room scatter, as well as the solution method were investigated in detail. Results: The average measurements when using the inverse N{sub K} interpolation method for the Classic Nucletron, Nucletron microSelectron, VariSource VS2000, GammaMed Plus, and Flexisource were found to be 0.47%, -0.10%, -1.13%, -0.20%, and 0.89% different than the existing standard, respectively. A further investigation of the differences observed between the sources was performed using MCNP5 Monte Carlo simulations of each source model inside a full model of an HDR 1000 Plus well chamber. Conclusions: Although the differences between the source models were found to be statistically significant, the equally weighted average difference between the seven-distance measurements and the well

Diffusion of Wilson loops

International Nuclear Information System (INIS)

Brzoska, A.M.; Lenz, F.; Thies, M.; Negele, J.W.

2005-01-01

A phenomenological analysis of the distribution of Wilson loops in SU(2) Yang-Mills theory is presented in which Wilson loop distributions are described as the result of a diffusion process on the group manifold. It is shown that, in the absence of forces, diffusion implies Casimir scaling and, conversely, exact Casimir scaling implies free diffusion. Screening processes occur if diffusion takes place in a potential. The crucial distinction between screening of fundamental and adjoint loops is formulated as a symmetry property related to the center symmetry of the underlying gauge theory. The results are expressed in terms of an effective Wilson loop action and compared with various limits of SU(2) Yang-Mills theory

Successful synthesis and thermal stability of immiscible metal Au-Rh, Au-Ir andAu-Ir-Rh nanoalloys

Science.gov (United States)

Shubin, Yury; Plyusnin, Pavel; Sharafutdinov, Marat; Makotchenko, Evgenia; Korenev, Sergey

2017-05-01

We successfully prepared face-centred cubic nanoalloys in systems of Au-Ir, Au-Rh and Au-Ir-Rh, with large bulk miscibility gaps, in one-run reactions under thermal decomposition of specially synthesised single-source precursors, namely, [AuEn2][Ir(NO2)6], [AuEn2][Ir(NO2)6] х [Rh(NO2)6]1-х and [AuEn2][Rh(NO2)6]. The precursors employed contain all desired metals ‘mixed’ at the atomic level, thus providing significant advantages for obtaining alloys. The observations using high-resolution transmission electron microscopy show that the nanoalloy structures are composed of well-dispersed aggregates of crystalline domains with a mean size of 5 ± 3 nm. Еnergy dispersive x-ray spectroscopy and x-ray powder diffraction (XRD) measurements confirm the formation of AuIr, AuRh, AuIr0.75Rh0.25, AuIr0.50Rh0.50 and AuIr0.25Rh0.75 metastable solid solutions. In situ high-temperature synchrotron XRD (HTXRD) was used to study the formation mechanism of nanoalloys. The observed transformations are described by the ‘conversion chemistry’ mechanism characterised by the primary development of particles comprising atoms of only one type, followed by a chemical reaction resulting in the final formation of a nanoalloy. The obtained metastable nanoalloys exhibit essential thermal stability. Exposure to 180 °C for 30 h does not cause any dealloying process.

On some properties of conjugacy closed loops

International Nuclear Information System (INIS)

Adeniran, John Olusola

2002-07-01

It is shown that central loops are not conjugacy closed loops but instead are loops of units in their loop algebras that are conjugacy closed. It is also shown that certain inner mappings of a conjugacy closed loop are nuclear. Some invariants of left conjugacy closed loops are obtained. (author)

Temperature control feedback loops for the linac upgrade side coupled cavities at Fermilab

International Nuclear Information System (INIS)

Crisp, J.

1990-01-01

The linac upgrade project at Fermilab will replace the last 4 drift-tube linac tanks with seven side coupled cavity strings. This will increase the beam energy from 200 to 400 MeV at injection into the Booster accelerator. The main objective of the temperature loop is to control the resonant frequency of the cavity strings. A cavity string will constant of 4 sections connected with bridge couplers driven with a 12 MW klystron at 805 MHz. Each section is a side coupled cavity chain consisting of 16 accelerating cells and 15 side coupling cells. For the linac upgrade, 7 full cavity strings will be used. A separate temperature control system is planned for each of the 28 accelerating sections, the two transition sections, and the debuncher section. The cavity strings will be tuned to resonance for full power beam loaded conditions. A separate frequency loop is planned that will sample the phase difference between a monitor placed in the end cell of each section and the rf drive. The frequency loop will control the set point for the temperature loop which will be able to maintain the resonant frequency through periods within beam or rf power. The frequency loop will need the intelligence required to determine under what conditions the phase error information is valid and the temperature set point should be adjusted. This paper will discuss some of the reason for temperature control, the implementation, and some of the problems encountered. An appendix contains some useful constants and descriptions of some of the sensor and control elements used. 13 figs

Characteristics of Ir/Au transition edge sensor

International Nuclear Information System (INIS)

Kunieda, Yuichi; Ohno, Masashi; Nakazawa, Masaharu; Takahashi, Hiroyuki; Fukuda, Daiji; Ohkubo, Masataka

2004-01-01

A new type of microcalorimeter has been developed using a transition edge sensor (TES) and an electro-thermal feedback (ETF) method to achieve higher energy resolution and higher count rate. We are developing a superconducting Ir-based transition edge sensor (TES) microcalorimeters. To improve thermal conductivity and achieve higher energy resolution with an Ir-TES, we fabricated an Ir/Au bilayer TES by depositing gold on Ir and investigated the influence of intermediate between superconducting and normal states at the transition edge for signal responses by microscopic observation in the Ir/Au-TES. (T. Tanaka)

Infrared (IR) photon-sensitive spectromicroscopy in a cryogenic environment

Science.gov (United States)

Pereverzev, Sergey

2016-06-14

A system designed to suppress thermal radiation background and to allow IR single-photon sensitive spectromicroscopy of small samples by using both absorption, reflection, and emission/luminescence measurements. The system in one embodiment includes: a light source; a plurality of cold mirrors configured to direct light along a beam path; a cold or warm sample holder in the beam path; windows of sample holder (or whole sample holder) are transparent in a spectral region of interest, so they do not emit thermal radiation in the same spectral region of interest; a cold monochromator or other cold spectral device configured to direct a selected fraction of light onto a cold detector; a system of cold apertures and shields positioned along the beam path to prevent unwanted thermal radiation from arriving at the cold monochromator and/or the detector; a plurality of optical, IR and microwave filters positioned along the beam path and configured to adjust a spectral composition of light incident upon the sample under investigation and/or on the detector; a refrigerator configured to maintain the detector at a temperature below 1.0K; and an enclosure configured to: thermally insulate the light source, the plurality of mirrors, the sample holder, the cold monochromator and the refrigerator.

Jaunesnių ir vyresnių klasių mokinių konfliktų ir jų sprendimų ypatumai

OpenAIRE

Stočkutė, Jovita

2012-01-01

Tyrimo objektas – jaunesnių ir vyresnių klasių mokinių konfliktai ir jų sprendimų ypatumai. Tyrimo tikslas – išanalizuoti jaunesnių ir vyresnių klasių mokinių konfliktus ir jų sprendimų ypatumus. Hipotezės – keliame prielaidas, kad - vyresnių klasių mokiniai konfliktuoti pamokose linkę labiau, nei jaunesnių klasių mokiniai. - vyresnių klasių mokiniai naudoja įvairesnes konflikto sprendimo strategijas nei jaunesnių klasių mokiniai. Tyrimo uždaviniai: 1. Atskleisti jaune...

Mirror symmetry and loop operators

Energy Technology Data Exchange (ETDEWEB)

Assel, Benjamin [Department of Mathematics, King’s College London,The Strand, London WC2R 2LS (United Kingdom); Gomis, Jaume [Perimeter Institute for Theoretical Physics,Waterloo, Ontario, N2L 2Y5 (Canada)

2015-11-09

Wilson loops in gauge theories pose a fundamental challenge for dualities. Wilson loops are labeled by a representation of the gauge group and should map under duality to loop operators labeled by the same data, yet generically, dual theories have completely different gauge groups. In this paper we resolve this conundrum for three dimensional mirror symmetry. We show that Wilson loops are exchanged under mirror symmetry with Vortex loop operators, whose microscopic definition in terms of a supersymmetric quantum mechanics coupled to the theory encode in a non-trivial way a representation of the original gauge group, despite that the gauge groups of mirror theories can be radically different. Our predictions for the mirror map, which we derive guided by branes in string theory, are confirmed by the computation of the exact expectation value of Wilson and Vortex loop operators on the three-sphere.

Teaching IR to Medical Students: A Call to Action.

Science.gov (United States)

Lee, Aoife M; Lee, Michael J

2018-02-01

Interventional radiology (IR) has grown rapidly over the last 20 years and is now an essential component of modern medicine. Despite IR's increasing penetration and reputation in healthcare systems, IR is poorly taught, if taught at all, in most medical schools. Medical students are the referrers of tomorrow and potential IR recruits and deserve to be taught IR by expert IRs. The lack of formal IR teaching curricula in many medical schools needs to be addressed urgently for the continued development and dissemination of, particularly acute, IR services throughout Europe. We call on IRs to take up the baton to teach IR to the next generation of doctors.

Iridium Interfacial Stack - IrIS

Science.gov (United States)

Spry, David

2012-01-01

Iridium Interfacial Stack (IrIS) is the sputter deposition of high-purity tantalum silicide (TaSi2-400 nm)/platinum (Pt-200 nm)/iridium (Ir-200 nm)/platinum (Pt-200 nm) in an ultra-high vacuum system followed by a 600 C anneal in nitrogen for 30 minutes. IrIS simultaneously acts as both a bond metal and a diffusion barrier. This bondable metallization that also acts as a diffusion barrier can prevent oxygen from air and gold from the wire-bond from infiltrating silicon carbide (SiC) monolithically integrated circuits (ICs) operating above 500 C in air for over 1,000 hours. This TaSi2/Pt/Ir/Pt metallization is easily bonded for electrical connection to off-chip circuitry and does not require extra anneals or masking steps. There are two ways that IrIS can be used in SiC ICs for applications above 500 C: it can be put directly on a SiC ohmic contact metal, such as Ti, or be used as a bond metal residing on top of an interconnect metal. For simplicity, only the use as a bond metal is discussed. The layer thickness ratio of TaSi2 to the first Pt layer deposited thereon should be 2:1. This will allow Si from the TaSi2 to react with the Pt to form Pt2Si during the 600 C anneal carried out after all layers have been deposited. The Ir layer does not readily form a silicide at 600 C, and thereby prevents the Si from migrating into the top-most Pt layer during future anneals and high-temperature IC operation. The second (i.e., top-most) deposited Pt layer needs to be about 200 nm to enable easy wire bonding. The thickness of 200 nm for Ir was chosen for initial experiments; further optimization of the Ir layer thickness may be possible via further experimentation. Ir itself is not easily wire-bonded because of its hardness and much higher melting point than Pt. Below the iridium layer, the TaSi2 and Pt react and form desired Pt2Si during the post-deposition anneal while above the iridium layer remains pure Pt as desired to facilitate easy and strong wire-bonding to the Si

The Heating of Solar Coronal Loops by Alfvén Wave Turbulence

Energy Technology Data Exchange (ETDEWEB)

Van Ballegooijen, A. A. [5001 Riverwood Avenue, Sarasota, FL 34231 (United States); Asgari-Targhi, M.; Voss, A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2017-11-01

In this paper we further develop a model for the heating of coronal loops by Alfvén wave turbulence (AWT). The Alfvén waves are assumed to be launched from a collection of kilogauss flux tubes in the photosphere at the two ends of the loop. Using a three-dimensional magnetohydrodynamic model for an active-region loop, we investigate how the waves from neighboring flux tubes interact in the chromosphere and corona. For a particular combination of model parameters we find that AWT can produce enough heat to maintain a peak temperature of about 2.5 MK, somewhat lower than the temperatures of 3–4 MK observed in the cores of active regions. The heating rates vary strongly in space and time, but the simulated heating events have durations less than 1 minute and are unlikely to reproduce the observed broad differential emission measure distributions of active regions. The simulated spectral line nonthermal widths are predicted to be about 27 km s{sup −1}, which is high compared to the observed values. Therefore, the present AWT model does not satisfy the observational constraints. An alternative “magnetic braiding” model is considered in which the coronal field lines are subject to slow random footpoint motions, but we find that such long-period motions produce much less heating than the shorter-period waves launched within the flux tubes. We discuss several possibilities for resolving the problem of producing sufficiently hot loops in active regions.

Optimal fit of chairside-fabricated distal shoe space maintainer.

Science.gov (United States)

Nouri, M R; Kennedy, D B

2013-10-01

Premature loss of a primary second molar may lead to space loss in the dental arch. This space loss tends to be more severe in unfavourable malocclusions. The distal shoe space maintainer (DSSM) may be beneficial in controlling the path of eruption of an unerupted permanent first molar from the primary into the early mixed dentition. This article describes the technique for achieving optimal fit of a chairside-fabricated band and DSSM in a single visit by contouring the distal shoe blade, and by extending it to the mesial surface of the permanent first molar. Upon the eruption of the permanent first molar DSSM may be modified to a reverse band-and-loop, or replaced by a lingual holding arch.

Modular high-voltage bias generator powered by dual-looped self-adaptive wireless power transmission.

Science.gov (United States)

Xie, Kai; Huang, An-Feng; Li, Xiao-Ping; Guo, Shi-Zhong; Zhang, Han-Lu

2015-04-01

We proposed a modular high-voltage (HV) bias generator powered by a novel transmitter-sharing inductive coupled wireless power transmission technology, aimed to extend the generator's flexibility and configurability. To solve the problems caused through an uncertain number of modules, a dual-looped self-adaptive control method is proposed that is capable of tracking resonance frequency while maintaining a relatively stable induction voltage for each HV module. The method combines a phase-locked loop and a current feedback loop, which ensures an accurate resonance state and a relatively constant boost ratio for each module, simplifying the architecture of the boost stage and improving the total efficiency. The prototype was built and tested. The input voltage drop of each module is less than 14% if the module number varies from 3 to 10; resonance tracking is completed within 60 ms. The efficiency of the coupling structure reaches up to 95%, whereas the total efficiency approaches 73% for a rated output. Furthermore, this technology can be used in various multi-load wireless power supply applications.

OH/IR stars in the Galaxy

International Nuclear Information System (INIS)

Baud, B.

1978-01-01

Radio astronomical observations leading to the discovery of 71 OH/IR sources are described in this thesis. These OH/IR sources are characterized by their double peaked OH emission profile at a wavelength of 18 cm and by their strong IR infrared emission. An analysis of the distribution and radial velocities of a number of previously known and new OH/IR sources was performed. The parameter ΔV (the velocity separation between two emission peaks of the 18 cm line profile) was found to be a good criterion for a population classification with respect to stellar age

First-principles study on cubic pyrochlore iridates Y2Ir2O7 and Pr2Ir2O7

International Nuclear Information System (INIS)

Ishii, Fumiyuki; Mizuta, Yo Pierre; Kato, Takehiro; Ozaki, Taisuke; Weng Hongming; Onoda, Shigeki

2015-01-01

Fully relativistic first-principles electronic structure calculations based on a noncollinear local spin density approximation (LSDA) are performed for pyrochlore iridates Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 . The all-in, all-out antiferromagnetic (AF) order is stablized by the on-site Coulomb repulsion U > U c in the LSDA+U scheme, with U c ∼ 1.1 eV and 1.3 eV for Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 , respectively. AF semimetals with and without Weyl points and then a topologically trivial AF insulator successively appear with further increasing U. For U = 1.3 eV, Y 2 Ir 2 O 7 is a topologically trivial narrow-gap AF insulator having an ordered local magnetic moment ∼0.5μ B /Ir, while Pr 2 Ir 2 O 7 is barely a paramagnetic semimetal with electron and hole concentrations of 0.016/Ir, in overall agreements with experiments. With decreasing oxygen position parameter x describing the trigonal compression of IrO 6 octahedra, Pr 2 Ir 2 O 7 is driven through a non-Fermi-liquid semimetal having only an isolated Fermi point of Γ 8 + , showing a quadratic band touching, to a Z 2 topological insulator. (author)

WWER type reactor primary loop imitation on large test loop facility in MARIA reactor

International Nuclear Information System (INIS)

Moldysh, A.; Strupchevski, A.; Kmetek, Eh.; Spasskov, V.P.; Shumskij, A.M.

1982-01-01

At present in Poland in cooperation with USSR a nuclear water loop test facility (WL) in 'MARIA' reactor in Sverke is under construction. The program objective is to investigate processes occuring in WWER reactor under emergency conditions, first of all after the break of the mainprimary loop circulation pipe-line. WL with the power of about 600 kW consists of three major parts: 1) an active loop, imitating the undamaged loops of the WWER reactor; 2) a passive loop assignedfor modelling the broken loop of the WWER reactor; 3) the emergency core cooling system imitating the corresponding full-scale system. The fuel rod bundle consists of 18 1 m long rods. They were fabricated according to the standard WWER fuel technology. In the report some general principles of WWERbehaviour imitation under emergency conditions are given. They are based on the operation experience obtained from 'SEMISCALE' and 'LOFT' test facilities in the USA. A description of separate modelling factors and criteria effects on the development of 'LOCA'-type accident is presented (the break cross-section to the primary loop volume ratio, the pressure differential between inlet and outlet reactor chambers, the pressure drop rate in the loop, the coolant flow rate throuh the core etc.). As an example a comparison of calculated flow rate variations for the WWER-1000 reactor and the model during the loss-of-coolant accident with the main pipe-line break at the core inlet is given. Calculations have been carried out with the use of TECH'-M code [ru

Natively unstructured loops differ from other loops.

Directory of Open Access Journals (Sweden)

Avner Schlessinger

2007-07-01

Full Text Available Natively unstructured or disordered protein regions may increase the functional complexity of an organism; they are particularly abundant in eukaryotes and often evade structure determination. Many computational methods predict unstructured regions by training on outliers in otherwise well-ordered structures. Here, we introduce an approach that uses a neural network in a very different and novel way. We hypothesize that very long contiguous segments with nonregular secondary structure (NORS regions differ significantly from regular, well-structured loops, and that a method detecting such features could predict natively unstructured regions. Training our new method, NORSnet, on predicted information rather than on experimental data yielded three major advantages: it removed the overlap between testing and training, it systematically covered entire proteomes, and it explicitly focused on one particular aspect of unstructured regions with a simple structural interpretation, namely that they are loops. Our hypothesis was correct: well-structured and unstructured loops differ so substantially that NORSnet succeeded in their distinction. Benchmarks on previously used and new experimental data of unstructured regions revealed that NORSnet performed very well. Although it was not the best single prediction method, NORSnet was sufficiently accurate to flag unstructured regions in proteins that were previously not annotated. In one application, NORSnet revealed previously undetected unstructured regions in putative targets for structural genomics and may thereby contribute to increasing structural coverage of large eukaryotic families. NORSnet found unstructured regions more often in domain boundaries than expected at random. In another application, we estimated that 50%-70% of all worm proteins observed to have more than seven protein-protein interaction partners have unstructured regions. The comparative analysis between NORSnet and DISOPRED2 suggested

Radioluminescence dating: the IR emission of feldspar

International Nuclear Information System (INIS)

Schilles, Thomas.; Habermann, Jan

2000-01-01

A new luminescence reader for radioluminescence (RL) measurements is presented. The system allows detection of RL emissions in the near infrared region (IR). Basic bleaching properties of the IR-RL emission of feldspars are investigated. Sunlight-bleaching experiments as a test for sensitivity changes are presented. IR-bleaching experiments were carried out to obtain information about the underlying physical processes of the IR-RL emission

Pamokslo ir eseistikos sąveika Juliaus Sasnausko ir Giedrės Kazlauskaitės eseistikoje

OpenAIRE

Skirmantienė, Daiva

2010-01-01

Jaunosios kartos rašytojų kunigo pamokslininko Juliaus Sasnausko ir pasaulietės Giedrės Kazlauskaitės kūrybos semantinį ir įdėjinį lauką padeda suprasti teologinės literatūros ir literatūrinės teologijos sąveika. Teologinių prasmių paieška jų tekstuose atliepia šiuolaikinio žmogaus pastangas per literatūrą, skelbiančią gyvenamojo laikotarpio aktualijas, rasti kelią į tam tikras krikščioniškąsias tiesas ir bandyti reflektuoti savo tikėjimą bei analizuoti išganymo istoriją. Autorių kūryo...

β-Isocyanoalanine as an IR probe: comparison of vibrational dynamics between isonitrile and nitrile-derivatized IR probes.

Science.gov (United States)

Maj, Michał; Ahn, Changwoo; Kossowska, Dorota; Park, Kwanghee; Kwak, Kyungwon; Han, Hogyu; Cho, Minhaeng

2015-05-07

An infrared (IR) probe based on isonitrile (NC)-derivatized alanine 1 was synthesized and the vibrational properties of its NC stretching mode were investigated using FTIR and femtosecond IR pump-probe spectroscopy. It is found that the NC stretching mode is very sensitive to the hydrogen-bonding ability of solvent molecules. Moreover, its transition dipole strength is larger than that of nitrile (CN) in nitrile-derivatized IR probe 2. The vibrational lifetime of the NC stretching mode is found to be 5.5 ± 0.2 ps in both D2O and DMF solvents, which is several times longer than that of the azido (N3) stretching mode in azido-derivatized IR probe 3. Altogether these properties suggest that the NC group can be a very promising sensing moiety of IR probes for studying the solvation structure and dynamics of biomolecules.

A type of loop algebra and the associated loop algebras

International Nuclear Information System (INIS)

Tam Honwah; Zhang Yufeng

2008-01-01

A higher-dimensional twisted loop algebra is constructed. As its application, a new Lax pair is presented, whose compatibility gives rise to a Liouville integrable hierarchy of evolution equations by making use of Tu scheme. One of the reduction cases of the hierarchy is an analogous of the well-known AKNS system. Next, the twisted loop algebra, furthermore, is extended to another higher dimensional loop algebra, from which a hierarchy of evolution equations with 11-potential component functions is obtained, whose reduction is just standard AKNS system. Especially, we prove that an arbitrary linear combination of the four Hamiltonian operators directly obtained from the recurrence relations is still a Hamiltonian operator. Therefore, the hierarchy with 11-potential functions possesses 4-Hamiltonian structures. Finally, an integrable coupling of the hierarchy is worked out

Joint IAEA/NEA IRS guidelines

International Nuclear Information System (INIS)

1997-01-01

The Incident Reporting System (IRS) is an international system jointly operated by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA). The fundamental objective of the IRS is to contribute to improving the safety of commercial nuclear power plants (NPPs) which are operated worldwide. This objective can be achieved by providing timely and detailed information on both technical and human factors related to events of safety significance which occur at these plants. The purpose of these guidelines, which supersede the previous IAEA Safety Series No. 93 (Part II) and the NEA IRS guidelines, is to describe the system and to give users the necessary background and guidance to enable them to produce IRS reports meeting a high standard of quality while retaining the high efficiency of the system expected by all Member States operating nuclear power plants

CD-loop Extension in Zika Virus Envelope Protein Key for Stability and Pathogenesis.

Science.gov (United States)

Gallichotte, Emily N; Dinnon, Kenneth H; Lim, Xin-Ni; Ng, Thiam-Seng; Lim, Elisa X Y; Menachery, Vineet D; Lok, Shee-Mei; Baric, Ralph S

2017-12-05

With severe disease manifestations including microcephaly, congenital malformation, and Guillain-Barré syndrome, Zika virus (ZIKV) remains a persistent global public health threat. Despite antigenic similarities with dengue viruses, structural studies have suggested the extended CD-loop and hydrogen-bonding interaction network within the ZIKV envelope protein contribute to stability differences between the viral families. This enhanced stability may lead to the augmented infection, disease manifestation, and persistence in body fluids seen following ZIKV infection. To examine the role of these motifs in infection, we generated a series of ZIKV recombinant viruses that disrupted the hydrogen-bonding network (350A, 351A, and 350A/351A) or the CD-loop extension (Δ346). Our results demonstrate a key role for the ZIKV extended CD-loop in cell-type-dependent replication, virion stability, and in vivo pathogenesis. Importantly, the Δ346 mutant maintains similar antigenicity to wild-type virus, opening the possibility for its use as a live-attenuated vaccine platform for ZIKV and other clinically relevant flaviviruses. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Modeling of compact loop antennas

International Nuclear Information System (INIS)

Baity, F.W.

1987-01-01

A general compact loop antenna model which treats all elements of the antenna as lossy transmission lines has been developed. In addition to capacitively-tuned resonant double loop (RDL) antennas the model treats stub-tuned resonant double loop antennas. Calculations using the model have been compared with measurements on full-scale mockups of resonant double loop antennas for ATF and TFTR in order to refine the transmission line parameters. Results from the model are presented for RDL antenna designs for ATF, TFTR, Tore Supra, and for the Compact Ignition Tokamak

CCD and IR array controllers

Science.gov (United States)

Leach, Robert W.; Low, Frank J.

2000-08-01

A family of controllers has bene developed that is powerful and flexible enough to operate a wide range of CCD and IR focal plane arrays in a variety of ground-based applications. These include fast readout of small CCD and IR arrays for adaptive optics applications, slow readout of large CCD and IR mosaics, and single CCD and IR array operation at low background/low noise regimes as well as high background/high speed regimes. The CCD and IR controllers have a common digital core based on user- programmable digital signal processors that are used to generate the array clocking and signal processing signals customized for each application. A fiber optic link passes image data and commands to VME or PCI interface boards resident in a host computer to the controller. CCD signal processing is done with a dual slope integrator operating at speeds of up to one Megapixel per second per channel. Signal processing of IR arrays is done either with a dual channel video processor or a four channel video processor that has built-in image memory and a coadder to 32-bit precision for operating high background arrays. Recent developments underway include the implementation of a fast fiber optic data link operating at a speed of 12.5 Megapixels per second for fast image transfer from the controller to the host computer, and supporting image acquisition software and device drivers for the PCI interface board for the Sun Solaris, Linux and Windows 2000 operating systems.

Įvairialyčiai lantano ir mangano oksido ir multiferoinio bismuto ferito heterodariniai

Directory of Open Access Journals (Sweden)

Bonifacas VENGALIS

2011-11-01

Full Text Available Pastaruoju metu naujų elektronikos prietaisų gamyboje buvo pasiekta didelė pažanga auginant, tyrinėjant ir pritaikant plonasluoksnes struktūras, sudarytas iš įvairių daugiakomponenčių funkcinių oksidų. Šiai oksidų grupei priklauso superlaidieji kupratai, mangano oksidai (manganitai, pasižymintys magnetovaržos reiškiniu, taip pat kiti feromagnetiniai, feroelektriniai, multiferoiniai oksidai. Manganitams (jų bendra formulė Ln1-xAxMnO3, kur Ln = La, Nd,..., o A - dvivalentis katijonas, toks kaip Ba, Sr ar Ca skiriama daug dėmesio dėl jų įdomių elektrinių savybių bei tinkamumo įvairiems spintronikos prietaisams kurti. Multiferoikai  (feroelektriniai feromagnetai pasižymi magnetoelektriniu efektu, duodančiu unikalią galimybę elektrinėms ir magnetinėms medžiagos savybėms valdyti panaudoti elektrinius ir magnetinius laukus. Bismuto feritas BiFeO3 (BFO, turintis romboedriškai deformuotą perovskito struktūrą, šiuo metu yra vienas labiausiai tyrinėjamų šios klasės junginių. Organiniai puslaidininkiai (OP taip pat atveria daug naujų galimybių elektronikai. Jų pranašumas yra didelė organinių junginių įvairovė ir palyginti paprasta ir pigi plonų sluoksnių gamybos technologija. Be to, OP pasižymi neįprastai didelėmis sukinių relaksacijos laiko vertėmis, todėl ateityje jie gali būti naudojami naujiems spintronikos prietaisams gaminti. Šiame straipsnyje apžvelgiami pastarųjų metų darbo autorių ir jų kolegų atlikti anksčiau minėtų medžiagų tyrimai. Daugiausia dėmesio skiriama magnetovaržinėmis savybėmis pasižyminčių lantano ir mangano oksidų (manganitų bei multiferoinio  BiFeO3 (BFO junginio plonųjų sluoksnių ir heterodarinių auginimui, tarpfazinių ribų tarp minėtų oksidų, laidžiojo SrTiO3 ir organinio puslaidininkio (Alq3 sudarymui, taip pat elektrinėms heterodarinių savybėms. Plonieji La2/3A1/3MnO3 (A = Ca, Sr, Ba, Ce sluoksniai, kurių storis d

Rogowski Loop design for NSTX

International Nuclear Information System (INIS)

McCormack, B.; Kaita, R.; Kugel, H.; Hatcher, R.

2000-01-01

The Rogowski Loop is one of the most basic diagnostics for tokamak operations. On the National Spherical Torus Experiment (NSTX), the plasma current Rogowski Loop had the constraints of the very limited space available on the center stack, 5,000 volt isolation, flexibility requirements as it remained a part of the Center Stack assembly after the first phase of operation, and a +120 C temperature requirement. For the second phase of operation, four Halo Current Rogowski Loops under the Center Stack tiles will be installed having +600 C and limited space requirements. Also as part of the second operational phase, up to ten Rogowski Loops will installed to measure eddy currents in the Passive Plate support structures with +350 C, restricted space, and flexibility requirements. This presentation will provide the details of the material selection, fabrication techniques, testing, and installation results of the Rogowski Loops that were fabricated for the high temperature operational and bakeout requirements, high voltage isolation requirements, and the space and flexibility requirements imposed upon the Rogowski Loops. In the future operational phases of NSTX, additional Rogowski Loops could be anticipated that will measure toroidal plasma currents in the vacuum vessel and in the Passive Plate assemblies

Hybrid Combustion-Gasification Chemical Looping

Energy Technology Data Exchange (ETDEWEB)

Herbert Andrus; Gregory Burns; John Chiu; Gregory Lijedahl; Peter Stromberg; Paul Thibeault

2009-01-07

For the past several years Alstom Power Inc. (Alstom), a leading world-wide power system manufacturer and supplier, has been in the initial stages of developing an entirely new, ultra-clean, low cost, high efficiency power plant for the global power market. This new power plant concept is based on a hybrid combustion-gasification process utilizing high temperature chemical and thermal looping technology The process consists of the oxidation, reduction, carbonation, and calcination of calcium-based compounds, which chemically react with coal, biomass, or opportunity fuels in two chemical loops and one thermal loop. The chemical and thermal looping technology can be alternatively configured as (i) a combustion-based steam power plant with CO{sub 2} capture, (ii) a hybrid combustion-gasification process producing a syngas for gas turbines or fuel cells, or (iii) an integrated hybrid combustion-gasification process producing hydrogen for gas turbines, fuel cells or other hydrogen based applications while also producing a separate stream of CO{sub 2} for use or sequestration. In its most advanced configuration, this new concept offers the promise to become the technology link from today's Rankine cycle steam power plants to tomorrow's advanced energy plants. The objective of this work is to develop and verify the high temperature chemical and thermal looping process concept at a small-scale pilot facility in order to enable AL to design, construct and demonstrate a pre-commercial, prototype version of this advanced system. In support of this objective, Alstom and DOE started a multi-year program, under this contract. Before the contract started, in a preliminary phase (Phase 0) Alstom funded and built the required small-scale pilot facility (Process Development Unit, PDU) at its Power Plant Laboratories in Windsor, Connecticut. Construction was completed in calendar year 2003. The objective for Phase I was to develop the indirect combustion loop with CO{sub 2

Thermal-hydraulic analyses for in-pile SCWR fuel qualification test loops and SCWR material loop

Energy Technology Data Exchange (ETDEWEB)

Vojacek, A.; Mazzini, G.; Zmitkova, J.; Ruzickova, M. [Research Centre Rez (Czech Republic)

2014-07-01

One of the R&D directions of Research Centre Rez is dedicated to the supercritical water-cooled reactor concept (SCWR). Among the developed experimental facilities and infrastructure in the framework of the SUSEN project (SUStainable ENergy) is construction and experimental operation of the supercritical water loop SCWL focusing on material tests. At the first phase, this SCWL loop is assembled and operated out-of-pile in the dedicated loop facilities hall. At this out-of-pile operation various operational conditions are tested and verified. After that, in the second phase, the SCWL loop will be situated in-pile, in the core of the research reactor LVR-15, operated at CVR. Furthermore, it is planned to carry out a test of a small scale fuel assembly within the SuperCritical Water Reactor Fuel Qualification Test (SCWR-FQT) loop, which is now being designed. This paper presents the results of the thermal-hydraulic analyses of SCWL loop out-of-pile operation using the RELAP5/MOD3.3. The thermal-hydraulic modeling and the performed analyses are focused on the SCWL loop model validation through a comparison of the calculation results with the experimental results obtained at various operation conditions. Further, the present paper focuses on the transient analyses for start-up and shut-down of the FQT loop, particularly to explore the ability of system codes ATHLET 3.0A to simulate the transient between subcritical conditions and supercritical conditions. (author)

Closed loop engine control for regulating NOx emissions, using a two-dimensional fuel-air curve

Science.gov (United States)

Bourn, Gary D.; Smith, Jack A.; Gingrich, Jess W.

2007-01-30

An engine control strategy that ensures that NOx emissions from the engine will be maintained at an acceptable level. The control strategy is based on a two-dimensional fuel-air curve, in which air manifold pressure (AMP) is a function of fuel header pressure and engine speed. The control strategy provides for closed loop NOx adjustment to a base AMP value derived from the fuel-air curve.

General report IRS-literature 1965-1976

International Nuclear Information System (INIS)

Schulz, W.

1976-12-01

The Institut fuer Reaktorsicherheit der TUeV e.V. (IRS) is of central importance in matters of licensing. It was jointly founded in 1965 by the eleven TUeVs of the Federal Republic of Germany and West-Berlin, by the Germanischer Lloyd and the then Federal Ministry for Scientific Research. After 12 sucsessful years the IRS will terminate its activities on December 31st, 1976, and together with the Laboratorium fuer Reaktorregelung und Anlagensicherung (LRA) at the TU Munich, Garching, it will be from January 1st, 1977 onwards part of the Gesellschaft fuer Reaktorsicherheit (GRS) mbH, a newly founded corporation. The activities of IRS and LRA will be continued by the GRS starting from January 1st, 1977. All IRS' report series and information services listed in this report are thus running out. The new corporation will build up its publications on the basis of the experience gained by IRS and LRA. (orig.) [de

Algorithm for counting large directed loops

Energy Technology Data Exchange (ETDEWEB)

Bianconi, Ginestra [Abdus Salam International Center for Theoretical Physics, Strada Costiera 11, 34014 Trieste (Italy); Gulbahce, Natali [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, NM 87545 (United States)

2008-06-06

We derive a Belief-Propagation algorithm for counting large loops in a directed network. We evaluate the distribution of the number of small loops in a directed random network with given degree sequence. We apply the algorithm to a few characteristic directed networks of various network sizes and loop structures and compare the algorithm with exhaustive counting results when possible. The algorithm is adequate in estimating loop counts for large directed networks and can be used to compare the loop structure of directed networks and their randomized counterparts.

Oscillation damping of chiral string loops

International Nuclear Information System (INIS)

Babichev, Eugeny; Dokuchaev, Vyacheslav

2002-01-01

Chiral cosmic string loops tend to the stationary (vorton) configuration due to energy loss into gravitational and electromagnetic radiation. We describe the asymptotic behavior of near stationary chiral loops and their fading to vortons. General limits on the gravitational and electromagnetic energy losses by near stationary chiral loops are found. For these loops we estimate the oscillation damping time. We present solvable examples of gravitational radiation energy loss by some chiral loop configurations. The analytical dependence of string energy with time is found in the case of the chiral ring with small amplitude radial oscillations

ϕ 3 theory with F4 flavor symmetry in 6 - 2 ɛ dimensions: 3-loop renormalization and conformal bootstrap

Science.gov (United States)

Pang, Yi; Rong, Junchen; Su, Ning

2016-12-01

We consider ϕ 3 theory in 6 - 2 ɛ with F 4 global symmetry. The beta function is calculated up to 3 loops, and a stable unitary IR fixed point is observed. The anomalous dimensions of operators quadratic or cubic in ϕ are also computed. We then employ conformal bootstrap technique to study the fixed point predicted from the perturbative approach. For each putative scaling dimension of ϕ (Δ ϕ ), we obtain the corresponding upper bound on the scaling dimension of the second lowest scalar primary in the 26 representation ( Δ 26 2nd ) which appears in the OPE of ϕ × ϕ. In D = 5 .95, we observe a sharp peak on the upper bound curve located at Δ ϕ equal to the value predicted by the 3-loop computation. In D = 5, we observe a weak kink on the upper bound curve at ( Δ ϕ , Δ 26 2nd ) = (1.6, 4).

LoopX: A Graphical User Interface-Based Database for Comprehensive Analysis and Comparative Evaluation of Loops from Protein Structures.

Science.gov (United States)

Kadumuri, Rajashekar Varma; Vadrevu, Ramakrishna

2017-10-01

Due to their crucial role in function, folding, and stability, protein loops are being targeted for grafting/designing to create novel or alter existing functionality and improve stability and foldability. With a view to facilitate a thorough analysis and effectual search options for extracting and comparing loops for sequence and structural compatibility, we developed, LoopX a comprehensively compiled library of sequence and conformational features of ∼700,000 loops from protein structures. The database equipped with a graphical user interface is empowered with diverse query tools and search algorithms, with various rendering options to visualize the sequence- and structural-level information along with hydrogen bonding patterns, backbone φ, ψ dihedral angles of both the target and candidate loops. Two new features (i) conservation of the polar/nonpolar environment and (ii) conservation of sequence and conformation of specific residues within the loops have also been incorporated in the search and retrieval of compatible loops for a chosen target loop. Thus, the LoopX server not only serves as a database and visualization tool for sequence and structural analysis of protein loops but also aids in extracting and comparing candidate loops for a given target loop based on user-defined search options.

Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Rector, Tony; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

A water loop maintenance device and process to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been undergoing a performance evaluation. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the water recirculation maintenance device and process is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance process further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware. This

Midterm Experience of Ipsilateral Axillary-Axillary Arteriovenous Loop Graft as Tertiary Access for Haemodialysis

Directory of Open Access Journals (Sweden)

J. P. Hunter

2014-01-01

Full Text Available Objectives. To present a series of ipsilateral axillary artery to axillary vein loop arm grafts as an alternative vascular access procedure for haemodialysis in patients with difficult access. Design. Retrospective case series. Methods. Patients who underwent an axillary loop arteriovenous graft from September 2009 to September 2012 were included. Preoperative venous imaging to exclude central venous stenosis and to image arm/axillary veins was performed. A cuffed PTFE graft was anastomosed to the distal axillary artery and axillary vein and looped on the arm. Results. 25 procedures were performed on 22 patients. Median age was 51 years, with 9 males and 13 females. Median number of previous access procedures was 3 (range 0–7. Median followup was 16.4 months (range 1–35. At 3 months and 1 year, the primary and secondary patency rates were 70% and 72% and 36% and 37%, respectively. There were 11 radiological interventions in 6 grafts including 5 angioplasties and 6 thrombectomies. There were 19 surgical procedures in 10 grafts, including thrombectomy, revision, repair for bleeding, and excision. Conclusions. Our series demonstrates that the axillary loop arm graft yields acceptable early patency rates in a complex group of patients but to maintain graft patency required high rates of surgical and radiological intervention, in particular graft thrombectomy.

256-MDCT for evaluation of urolithiasis: iterative reconstruction allows for a significant reduction of the applied radiation dose while maintaining high subjective and objective image quality

International Nuclear Information System (INIS)

Veldhoen, Simon; Laqmani, Azien; Derlin, Thorsten; Karul, Murat; Hammerle, Diego; Adam, Gerhard; Regier, Marc; Buhk, Jan-Hendrick; Sehner, Susanne; Nagel, Hans D.; Chun, Felix

2014-01-01

Multidetector CT (MDCT) is the established imaging modality in diagnostics of urolithiasis. The aim of iterative reconstruction (IR) is to allow for a radiation dose reduction while maintaining high image quality. This study evaluates its performance in MDCT for assessment of urolithiasis. Fifty-two patients underwent non-contrast abdominal MDCT. Twenty-six patients were referred to MDCT under suspicion of urolithiasis, and examined using a dose-reduced scan protocol (RDCT). Twenty-six patients, who had undergone standard-dose MDCT, served as reference for radiation dose comparison. RDCT images were reconstructed using an IR system (iDose4™, Philips Healthcare, Cleveland, OH, USA). Objective image noise (OIN) was recorded and five radiologists rated the subjective image quality independently. Radiation parameters were derived from the scan protocols. The CTDIvol could be reduced by 50% to 5.8 mGy (P < 0.0001). The same reduction was achieved for DLP and effective dose to 253 ± 27 mGy*cm (P < 0.0001) and 3.9 ± 0.4 mSv (P < 0.0001). IR led to a reduction of the OIN of up to 61% compared with classic filtered back projection (FBP) (P < 0.0001). The OIN declined with increasing IR levels. RDCT with FBP showed the lowest scores of subjective image quality (2.32 ± 0.04). Mean scores improved with increasing IR levels. iDose6 was rated with the best mean score (3.66 ± 0.04). The evaluated IR-tool and protocol may be applied to achieve a considerable radiation dose reduction in MDCT for diagnostics of urolithiasis while maintaining a confident image quality. Best image quality, suitable for evaluation of the entire abdomen concerning differential diagnoses, was achieved with iDose6.

3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses.

Science.gov (United States)

Kim, Nammoon; Kim, Youngok

2011-10-04

In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS) is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D) positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB) signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.

α-Lipoic acid stabilized DTX/IR780 micelles for photoacoustic/fluorescence imaging guided photothermal therapy/chemotherapy of breast cancer.

Science.gov (United States)

Li, WenTing; Peng, JinRong; Yang, Qian; Chen, LiJuan; Zhang, Lan; Chen, XiaoXin; Qian, ZhiYong

2018-05-01

Micellar nanoparticles have unique advantages as carriers for therapeutic or imaging agents, owing to their smaller size and better penetration of tumors. However, some agents, due to their physical or chemical properties, are difficult to load into micelles. IR780 is one of these agents, and is also a promising near-infrared dye for fluorescence imaging (FI)/photoacoustic imaging (PAI) and cancer photothermal therapy (PTT). Its hydrophobic and high crystallization structure results in limited bioavailability in vivo. It is difficult to load into micelles constructed from an amphiphilic block polymer with relatively low molecular weight. In this study, we use computer simulation and introduce another small biomolecule, α-lipoic acid, into the micelles constructed from a mPEG-PCL copolymer, to lower the energy of molecular interaction between MPEG-PCL and IR780, and expect to enhance the loading capacity of the micelles to IR780. The introduction of α-lipoic acid decreases the energy of molecular interaction between MEPG-PCL and IR780 from -46.18 kJ mol-1 to -196.52 kJ mol-1 and increases the loading capacity and stability of the mPEG-PCL micelles to IR780, which also maintains the loading capacity to DTX. We further construct DTX/IR780 co-loaded mPEG-PCL micelles for FI/PAI dual modal imaging guided PTT/chemotherapy of cancer. By FI and PAI evaluation in vitro and in vivo, we demonstrate that the DTX/IR780 co-loaded micelles can be used as FI and PAI probes. By further evaluating the therapeutic outcome of PTT/chemotherapy co-therapy of breast cancer, we demonstrate that the DTX/IR780 co-loaded mPEG-PCL micelles can serve as promising candidates for FI and PAI guided PTT/chemotherapy of breast cancer.

On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH{sub 3}){sub 4}][IrCl{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Asanova, Tatyana I., E-mail: nti@niic.nsc.ru; Asanov, Igor P. [Nikolaev Institute of Inorganic Chemistry SB RAS (Russian Federation); Kim, Min-Gyu [Pohang University of Science and Technology, Beamline Research Division (Korea, Republic of); Gerasimov, Evgeny Yu. [Boreskov Institute of Catalysis SB RAS (Russian Federation); Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V. [Nikolaev Institute of Inorganic Chemistry SB RAS (Russian Federation)

2013-10-15

The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH{sub 3}){sub 4}][IrCl{sub 6}] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 Degree-Sign C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.Graphical Abstract.

Intraoperative stroke volume optimization using stroke volume, arterial pressure, and heart rate: closed-loop (learning intravenous resuscitator) versus anesthesiologists.

Science.gov (United States)

Rinehart, Joseph; Chung, Elena; Canales, Cecilia; Cannesson, Maxime

2012-10-01

The authors compared the performance of a group of anesthesia providers to closed-loop (Learning Intravenous Resuscitator [LIR]) management in a simulated hemorrhage scenario using cardiac output monitoring. A prospective cohort study. In silico simulation. University hospital anesthesiologists and the LIR closed-loop fluid administration system. Using a patient simulator, a 90-minute simulated hemorrhage protocol was run, which included a 1,200-mL blood loss over 30 minutes. Twenty practicing anesthesiology providers were asked to manage this scenario by providing fluids and vasopressor medication at their discretion. The simulation program was also run 20 times with the LIR closed-loop algorithm managing fluids and an additional 20 times with no intervention. Simulated patient weight, height, heart rate, mean arterial pressure, and cardiac output (CO) were similar at baseline. The mean stroke volume, the mean arterial pressure, CO, and the final CO were higher in the closed-loop group than in the practitioners group, and the coefficient of variance was lower. The closed-loop group received slightly more fluid (2.1 v 1.9 L, p closed-loop maintained more stable hemodynamics than the practitioners primarily because the fluid was given earlier in the protocol and CO optimized before the hemorrhage began, whereas practitioners tended to resuscitate well but only after significant hemodynamic change indicated the need. Overall, these data support the potential usefulness of this closed-loop algorithm in clinical settings in which dynamic predictors are not available or applicable. Published by Elsevier Inc.

Activity uniformity of Ir-192 seeds

International Nuclear Information System (INIS)

Ling, C.C.; Gromadzki, Z.C.

1981-01-01

A simple device that uses materials and apparatus commonly available in a radiotherapy department has been designed, fabricated and used in routine quality control relative to the activity uniformity of clinical Ir-192 seeds in ribbons. Detailed evaluation indicated that this system is easy to use and can yield relative activity measurements of individual Ir-192 seeds accurate to within 2%. With this device, activity uniformity of commercial Ir-192 seeds from two manufacturers has been assessed. For the seven shipments of Ir-192 seeds studied, the root mean square variations of individual seed strength from the average of each shipment ranged from 3.4 to 7.1%. Variation in seed activity by more than +- 10% from the average is not uncommon

Persistent semi-metal-like nature of epitaxial perovskite CaIrO3 thin films

International Nuclear Information System (INIS)

Biswas, Abhijit; Jeong, Yoon Hee

2015-01-01

Strong spin-orbit coupled 5d transition metal based ABO 3 oxides, especially iridates, allow tuning parameters in the phase diagram and may demonstrate important functionalities, for example, by means of strain effects and symmetry-breaking, because of the interplay between the Coulomb interactions and strong spin-orbit coupling. Here, we have epitaxially stabilized high quality thin films of perovskite (Pv) CaIrO 3 . Film on the best lattice-matched substrate shows semi-metal-like characteristics. Intriguingly, imposing tensile or compressive strain on the film by altering the underlying lattice-mismatched substrates still maintains semi-metallicity with minute modification of the effective correlation as tensile (compressive) strain results in tiny increases (decreases) of the electronic bandwidth. In addition, magnetoresistance remains positive with a quadratic field dependence. This persistent semi-metal-like nature of Pv-CaIrO 3 thin films with minute changes in the effective correlation by strain may provide new wisdom into strong spin-orbit coupled 5d based oxide physics

Higher dimensional loop quantum cosmology

International Nuclear Information System (INIS)

Zhang, Xiangdong

2016-01-01

Loop quantum cosmology (LQC) is the symmetric sector of loop quantum gravity. In this paper, we generalize the structure of loop quantum cosmology to the theories with arbitrary spacetime dimensions. The isotropic and homogeneous cosmological model in n + 1 dimensions is quantized by the loop quantization method. Interestingly, we find that the underlying quantum theories are divided into two qualitatively different sectors according to spacetime dimensions. The effective Hamiltonian and modified dynamical equations of n + 1 dimensional LQC are obtained. Moreover, our results indicate that the classical big bang singularity is resolved in arbitrary spacetime dimensions by a quantum bounce. We also briefly discuss the similarities and differences between the n + 1 dimensional model and the 3 + 1 dimensional one. Our model serves as a first example of higher dimensional loop quantum cosmology and offers the possibility to investigate quantum gravity effects in higher dimensional cosmology. (orig.)

Hyperstaticity and loops in frictional granular packings

Science.gov (United States)

Tordesillas, Antoinette; Lam, Edward; Metzger, Philip T.

2009-06-01

The hyperstatic nature of granular packings of perfectly rigid disks is analyzed algebraically and through numerical simulation. The elementary loops of grains emerge as a fundamental element in addressing hyperstaticity. Loops consisting of an odd number of grains behave differently than those with an even number. For odd loops, the latent stresses are exterior and are characterized by the sum of frictional forces around each loop. For even loops, the latent stresses are interior and are characterized by the alternating sum of frictional forces around each loop. The statistics of these two types of loop sums are found to be Gibbsian with a "temperature" that is linear with the friction coefficient μ when μ<1.

Towards an Artificial Phonological Loop: An Assistive Device for Working Memory and Attentional Control

Directory of Open Access Journals (Sweden)

D. Bogen

2006-01-01

Full Text Available We describe the initial development of an artificial phonological loop (APL, a new technology to assist individuals with impairment of the working memory system. The phonological loop, along with the visuospatial sketchpad, is one of the two slave short-term memory subsystems that comprise working memory, a cognitive function closely associated with the control of attention. In the phonological loop, phonological (speech information lasting for 1–2 second is maintained active by repetitive, subvocal (silent speech rehearsal. Deficits in working memory, specifically in the phonological loop, occur in many disorders, including attention-deficit disorder and Alzheimer’s disease. In these disorders, it appears that the ability for phonological rehearsal is intact, but the regulation or triggering of the rehearsal process is inadequate, thus causing the contents of working memory to be lost. The purpose, then, of the APL is to facilitate the phonological loop by artificially extending the duration of phonological rehearsals. The APL mimics the natural phonological loop by providing audible vocal echoes to take the place of subvocal rehearsals. In this system, the user talks to him/herself in short (1–2 second phrases; the device records these phrases, stores them in electronic memory, and then repeats— i.e., echoes—the phrases multiple times over an extended period. Two versions of this device have been developed: the Echo-APL and the Rearticulation-APL. In the Echo-APL, only echoing is involved. In the Rearticulation-APL, however, the user re-vocalizes (rearticulates the phrase in response to an audible cue. The device repeats the cue until it detects (hears the re-vocalization. Future research and development of the APL will require extensive testing and careful evaluation of possible echo-schedules: the predefined program controlling inter-echo time intervals and echo-amplitude (echo loudness. The APL essentially exteriorizes the silent

Loop Heat Pipe Startup Behaviors

Science.gov (United States)

Ku, Jentung

2016-01-01

A loop heat pipe must start successfully before it can commence its service. The startup transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe startup behaviors. Topics include the four startup scenarios, the initial fluid distribution between the evaporator and reservoir that determines the startup scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power startup, and methods to enhance the startup success. Also addressed are the pressure spike and pressure surge during the startup transient, and repeated cycles of loop startup and shutdown under certain conditions.

Conformal boundary loop models

International Nuclear Information System (INIS)

Jacobsen, Jesper Lykke; Saleur, Hubert

2008-01-01

We study a model of densely packed self-avoiding loops on the annulus, related to the Temperley-Lieb algebra with an extra idempotent boundary generator. Four different weights are given to the loops, depending on their homotopy class and whether they touch the outer rim of the annulus. When the weight of a contractible bulk loop x≡q+q -1 element of (-2,2], this model is conformally invariant for any real weight of the remaining three parameters. We classify the conformal boundary conditions and give exact expressions for the corresponding boundary scaling dimensions. The amplitudes with which the sectors with any prescribed number and types of non-contractible loops appear in the full partition function Z are computed rigorously. Based on this, we write a number of identities involving Z which hold true for any finite size. When the weight of a contractible boundary loop y takes certain discrete values, y r ≡([r+1] q )/([r] q ) with r integer, other identities involving the standard characters K r,s of the Virasoro algebra are established. The connection with Dirichlet and Neumann boundary conditions in the O(n) model is discussed in detail, and new scaling dimensions are derived. When q is a root of unity and y=y r , exact connections with the A m type RSOS model are made. These involve precise relations between the spectra of the loop and RSOS model transfer matrices, valid in finite size. Finally, the results where y=y r are related to the theory of Temperley-Lieb cabling

Large lithium loop experience

International Nuclear Information System (INIS)

Kolowith, R.; Owen, T.J.; Berg, J.D.; Atwood, J.M.

1981-10-01

An engineering design and operating experience of a large, isothermal, lithium-coolant test loop are presented. This liquid metal coolant loop is called the Experimental Lithium System (ELS) and has operated safely and reliably for over 6500 hours through September 1981. The loop is used for full-scale testing of components for the Fusion Materials Irradiation Test (FMIT) Facility. Main system parameters include coolant temperatures to 430 0 C and flow to 0.038 m 3 /s (600 gal/min). Performance of the main pump, vacuum system, and control system is discussed. Unique test capabilities of the ELS are also discussed

Modular invariance and covariant loop calculus

International Nuclear Information System (INIS)

Petersen, J.L.; Roland, K.O.; Sidenius, J.R.

1988-01-01

The covariant loop calculus provides an efficient technique for computing explicit expressions for the density on moduli space corresponding to arbitrary (bosonic string) loop diagrams. Since modular invariance is not manifest, however, we carry out a detailed comparison with known explicit two- and three-loop results derived using analytic geometry (one loop is known to be okay). We establish identity to 'high' order in some moduli and exactly in others. Agreement is found as a result of various nontrivial cancellations, in part related to number theory. We feel our results provide very strong support for the correctness of the covariant loop calculus approach. (orig.)

Modular invariance and covariant loop calculus

International Nuclear Information System (INIS)

Petersen, J.L.; Roland, K.O.; Sidenius, J.R.

1988-01-01

The covariant loop calculus provides and efficient technique for computing explicit expressions for the density on moduli space corresponding to arbitrary (bosonic string) loop diagrams. Since modular invariance is not manifest, however, we carry out a detailed comparison with known explicit 2- and 3- loop results derived using analytic geometry (1 loop is known to be ok). We establish identity to 'high' order in some moduli and exactly in others. Agreement is found as a result of various non-trivial cancellations, in part related to number theory. We feel our results provide very strong support for the correctness of the covariant loop calculus approach. (orig.)

Thermal-to-visible transducer (TVT) for thermal-IR imaging

Science.gov (United States)

Flusberg, Allen; Swartz, Stephen; Huff, Michael; Gross, Steven

2008-04-01

We have been developing a novel thermal-to-visible transducer (TVT), an uncooled thermal-IR imager that is based on a Fabry-Perot Interferometer (FPI). The FPI-based IR imager can convert a thermal-IR image to a video electronic image. IR radiation that is emitted by an object in the scene is imaged onto an IR-absorbing material that is located within an FPI. Temperature variations generated by the spatial variations in the IR image intensity cause variations in optical thickness, modulating the reflectivity seen by a probe laser beam. The reflected probe is imaged onto a visible array, producing a visible image of the IR scene. This technology can provide low-cost IR cameras with excellent sensitivity, low power consumption, and the potential for self-registered fusion of thermal-IR and visible images. We will describe characteristics of requisite pixelated arrays that we have fabricated.

Parallel tiled Nussinov RNA folding loop nest generated using both dependence graph transitive closure and loop skewing.

Science.gov (United States)

Palkowski, Marek; Bielecki, Wlodzimierz

2017-06-02

RNA secondary structure prediction is a compute intensive task that lies at the core of several search algorithms in bioinformatics. Fortunately, the RNA folding approaches, such as the Nussinov base pair maximization, involve mathematical operations over affine control loops whose iteration space can be represented by the polyhedral model. Polyhedral compilation techniques have proven to be a powerful tool for optimization of dense array codes. However, classical affine loop nest transformations used with these techniques do not optimize effectively codes of dynamic programming of RNA structure predictions. The purpose of this paper is to present a novel approach allowing for generation of a parallel tiled Nussinov RNA loop nest exposing significantly higher performance than that of known related code. This effect is achieved due to improving code locality and calculation parallelization. In order to improve code locality, we apply our previously published technique of automatic loop nest tiling to all the three loops of the Nussinov loop nest. This approach first forms original rectangular 3D tiles and then corrects them to establish their validity by means of applying the transitive closure of a dependence graph. To produce parallel code, we apply the loop skewing technique to a tiled Nussinov loop nest. The technique is implemented as a part of the publicly available polyhedral source-to-source TRACO compiler. Generated code was run on modern Intel multi-core processors and coprocessors. We present the speed-up factor of generated Nussinov RNA parallel code and demonstrate that it is considerably faster than related codes in which only the two outer loops of the Nussinov loop nest are tiled.

Isolated Gramicidin Peptides Probed by IR Spectroscopy

NARCIS (Netherlands)

Rijs, A. M.; Kabelac, M.; Abo-Riziq, A.; Hobza, P.; de Vries, M. S.

2011-01-01

We report double-resonant IR/UV ion-dip spectroscopy of neutral gramicidin peptides in the gas phase. The IR spectra of gramicidin A and C, recorded in both the 1000 cm(-1) to 1800 cm(-1) and the 2700 to 3750 cm(-1) region, allow structural analysis. By studying this broad IR range, various local

Braškių 'Senga Sengana' prisitaikymas prie diferencijuoto ir kompleksinio UV-B spinduliuotės ir ozono poveikio

OpenAIRE

Brazaitytė, Aušra; Sakalauskaitė, Jurga; Duchovskis, Pavelas; Šikšnianienė, Jūratė Bronė; Samuolienė, Giedrė; Ulinskaitė, Raimonda; Baranauskis, Kęstutis; Urbonavičiūtė, Akvilė; Šabajevienė, Gintarė; Gelvonauskis, Bronislovas; Uselis, Nobertas; Vagusevičienė, Ilona

2007-01-01

2005 m. Lietuvos sodininkystės ir daržininkystės instituto fitotrono komplekse nustatytas diferencijuotas ir kompleksinis UV-B spinduliuotės bei ozono poveikis braškių augimui ir fotosintezės pigmentų pokyčiams bei jų prisitaikymo prie šių stresorių galimybės. Poveikis stresą sukeliančiais veiksniais buvo skirstomas į du laikotarpius: adaptacijos ir pagrindinį. Ozono koncentracija adaptacijos laikotarpiu buvo 80 µg m-3, o pagrindinio poveikio – 240 µg m-3. Tokia koncentracija buvo palaikoma 7...

Gauge theory loop operators and Liouville theory

International Nuclear Information System (INIS)

Drukker, Nadav; Teschner, Joerg

2009-10-01

We propose a correspondence between loop operators in a family of four dimensional N=2 gauge theories on S 4 - including Wilson, 't Hooft and dyonic operators - and Liouville theory loop operators on a Riemann surface. This extends the beautiful relation between the partition function of these N=2 gauge theories and Liouville correlators found by Alday, Gaiotto and Tachikawa. We show that the computation of these Liouville correlators with the insertion of a Liouville loop operator reproduces Pestun's formula capturing the expectation value of a Wilson loop operator in the corresponding gauge theory. We prove that our definition of Liouville loop operators is invariant under modular transformations, which given our correspondence, implies the conjectured action of S-duality on the gauge theory loop operators. Our computations in Liouville theory make an explicit prediction for the exact expectation value of 't Hooft and dyonic loop operators in these N=2 gauge theories. The Liouville loop operators are also found to admit a simple geometric interpretation within quantum Teichmueller theory as the quantum operators representing the length of geodesics. We study the algebra of Liouville loop operators and show that it gives evidence for our proposal as well as providing definite predictions for the operator product expansion of loop operators in gauge theory. (orig.)

New arrangements, new scrutiny. The IRS reconsiders hospital-physician relationships at tax-exempt facilities.

Science.gov (United States)

Sullivan, T J

1992-01-01

The pressure to maintain adequate operating margins has forced many not-for-profit hospitals to adopt more overtly competitive behavior than they have in the past. However, in struggling to remain economically viable, these facilities should carefully avoid actions that would threaten their tax-exempt status. Not-for-profit facilities should be particularly careful that their arrangements with physicians, which often appear designed to increase referrals, do not violate the criteria according to which the Internal Revenue Code extends tax exemption to charitable organizations. Section 501(c)(3) of the code exempts organizations "no part of the net earnings of which inures to the benefit of any private shareholder or individual." According to this provision, "insiders" (i.e., those with a personal interest in or opportunity to influence organization activities from the inside) are entitled to no more than reasonable payment for their goods or services. The Internal Revenue Service (IRS) takes the position that, as employees or individuals having a close professional working relationship with a hospital, physicians are insiders. Thus a hospital that pays physicians what the IRS judges to be more than fair market value for services (or charges physicians less than fair market value for office rental) may find its exemption in jeopardy. If not-for-profit hospitals want to maintain their tax-exempt status, they must be certain the arrangements they enter into with physicians truly further their exempt purpose: to promote the health of the community.

A True Open-Loop Synchronization Technique

DEFF Research Database (Denmark)

Golestan, Saeed; Vidal, Ana; Yepes, Alejandro G.

2016-01-01

Synchronization techniques can be broadly classified into two major categories: Closed-loop and open-loop methods. The open-loop synchronization (OLS) techniques, contrary to the closed-loop ones, are unconditionally stable and benefit from a fast dynamic response. Their performance, however, tends...... is to develop a true OLS (and therefore, unconditionally stable) technique without any need for the calculation of sine and cosine functions. The effectiveness of the proposed synchronization technique is confirmed through the simulation and experimental results....

A kinematic view of loop closure.

Science.gov (United States)

Coutsias, Evangelos A; Seok, Chaok; Jacobson, Matthew P; Dill, Ken A

2004-03-01

We consider the problem of loop closure, i.e., of finding the ensemble of possible backbone structures of a chain segment of a protein molecule that is geometrically consistent with preceding and following parts of the chain whose structures are given. We reduce this problem of determining the loop conformations of six torsions to finding the real roots of a 16th degree polynomial in one variable, based on the robotics literature on the kinematics of the equivalent rotator linkage in the most general case of oblique rotators. We provide a simple intuitive view and derivation of the polynomial for the case in which each of the three pair of torsional axes has a common point. Our method generalizes previous work on analytical loop closure in that the torsion angles need not be consecutive, and any rigid intervening segments are allowed between the free torsions. Our approach also allows for a small degree of flexibility in the bond angles and the peptide torsion angles; this substantially enlarges the space of solvable configurations as is demonstrated by an application of the method to the modeling of cyclic pentapeptides. We give further applications to two important problems. First, we show that this analytical loop closure algorithm can be efficiently combined with an existing loop-construction algorithm to sample loops longer than three residues. Second, we show that Monte Carlo minimization is made severalfold more efficient by employing the local moves generated by the loop closure algorithm, when applied to the global minimization of an eight-residue loop. Our loop closure algorithm is freely available at http://dillgroup. ucsf.edu/loop_closure/. Copyright 2004 Wiley Periodicals, Inc. J Comput Chem 25: 510-528, 2004

Fasting serum insulin and the homeostasis model of insulin resistance (HOMA-IR) in the monitoring of lifestyle interventions in obese persons.

Science.gov (United States)

Vogeser, Michael; König, Daniel; Frey, Ingrid; Predel, Hans-Georg; Parhofer, Klaus Georg; Berg, Aloys

2007-09-01

Lifestyle changes with increased physical activity and balanced energy intake are recognized as the principal interventions in obesity and insulin resistance. Only few prospective studies, however, have so far addressed the potential role of routine biochemical markers of insulin sensitivity in the monitoring of respective interventions. Fasting insulin and glucose was measured in 33 obese individuals undergoing a lifestyle modification program (MOBILIS) at baseline and after 1 year. The HOMA-IR index (homeostasis model of insulin resistance) was calculated as [fasting serum glucose*fasting serum insulin/22.5], with lower values indicating a higher degree of insulin sensitivity. While the median body mass index (BMI) and waist circumference decreased by 10% and 11%, respectively, the HOMA-IR index decreased in an over-proportional manner by 45% within 1 year (BMI baseline, median 35.7, interquartile range (IQR) 33.7-37.7; after 1 year, median 32.2, IQR 29.6-35.1. HOMA-IR baseline, median 2.9, IQR 1.5-4.6; after 1 year 1.6, IQR 0.9-2.7). In contrast to HOMA-IR and fasting serum insulin, no significant changes in fasting serum glucose were observed. Baseline and post-intervention HOMA-IR showed a high degree of inter-individual variation with eight individuals maintaining high HOMA-IR values despite weight loss after 1 year of intervention. Individual changes in the carbohydrate metabolism achieved by a lifestyle intervention program were displayed by fasting serum insulin concentrations and the HOMA-IR but not by fasting glucose measurement alone. Therefore, assessment of the HOMA-IR may help to individualize lifestyle interventions in obesity and to objectify improvements in insulin sensitivity after therapeutic lifestyle changes.

The Wilson loop and some applications

International Nuclear Information System (INIS)

Bezerra, V.B.

1983-01-01

A simple relation between the classical Wilson loop and the angular deviation in the parallel shift is found. An example of potential which given field copies and which give the same classical Wilson loop for a given trajectory is exchibited. Afterwards, the asymptotic behaviour of the Wilson loop for the BPST instanton and meron is discussed. Using the dimensional regularization technique to calculate the second order term of Quantum Wilson loop, the influence of geometrical factors for the residue in the polo due to contact points, cusp and intersections, in function of the upsilon dimension of the space-time is investigated. Finally, the charge renormalization in Quantum Electrodynamics using Quantum Wilson loop is calculated. (L.C.) [pt

The Wilson loop and some applications

International Nuclear Information System (INIS)

Bezerra, V.B.

1983-04-01

A simple relation between the classical Wilson loop and the angular deviation in the parallel displacement is found. An example of potentials which give field copies and which suplly the same classical Wilson loop for a particular trajectory is exhibited. The asymptotic behaviour of the Wilson loop for the BPST instanton and the meron, is discussed. By using the dimensional regularization technique to calculate the second order term of the quantum Wilson loop, the influence of geometrical factors for the residue in the pole due to contact points, cuspides and intersections, in function of the space-time ν, is investigated. Charge renormalization in Quantum electrodynamics is finally calculated by using the quantum Wilson loop. (L.C.) [pt

Vartotojų lojalumas : formavimas ir valdymas

OpenAIRE

Zikienė, Kristina

2010-01-01

Vienas iš esminių daugelio organizacijų tikslų, garantuojančių tolesnį sėkmingą konkuravimą nuolat besikeičiančiame verslo pasaulyje, yra vartotojų lojalumo įgijimas ir išlaikymas. Įvairios lojalumo formavimo ir valdymo problemos plačiai ir detaliai analizuojamos šioje mokomojoje knygoje. Knyga pradedama vartotojų lojalumo analize marketingo mokslo raidos kontekste. Tolesnis dėmesys skiriamas vartotojų lojalumo vadybinio aspekto analizei, atskleidžiant vartotojų lojalumo koncepcijos teorines ...

Broilerienos paklausa ir pasiūla Lietuvoje

OpenAIRE

Paškauskienė, Kristina

2008-01-01

Labai svarbu ir savalaikiškai ištirti vartotojų poreikį broilerienai, aktualu nustatyti vartotojų požiūrį į Lietuvoje užauginamą produkciją bei importuotą. ir kokia yra priklausomybė vyrų bei moterų tarpe, ir nuo gaunamo atlyginimo. Vartotojų tyrimai rodo, kad auga paklausa lengvai virškinamiems, greitai paruošiamiems, aukštos maistinės kokybės gyvulininkystės produktams. Darbo tikslas - Išsiaiškinti broilerienos paklausą ir pasiūlą Lietuvoje, įvertinti broilerienos suvartojimo tendencija...

One-Loop Operation of Primary Heat Transport System in MONJU During Heat Transport System Modifications

International Nuclear Information System (INIS)

Goto, T.; Tsushima, H.; Sakurai, N.; Jo, T.

2006-01-01

MONJU is a prototype fast breeder reactor (FBR). Modification work commenced in March 2005. Since June 2004, MONJU has changed to one-loop operation of the primary heat transport system (PHTS) with all of the secondary heat transport systems (SHTS) drained of sodium. The purposes of this change are to shorten the modification period and to reduce the cost incurred for circuit trace heating electrical consumption. Before changing condition, the following issues were investigated to show that this mode of operation was possible. The heat loss from the reactor vessel and the single primary loop must exceed the decay heat by an acceptable margin but the capacity of pre-heaters to keep the sodium within the primary vessel at about 200 deg. C must be maintained. With regard to the heat loss and the decay heat, the estimated heat loss in the primary system was in the range of 90-170 kW in one-loop operation, and the calculated decay heat was 21.2 kW. Although the heat input of the primary pump was considered, it was clear that circuit heat loss greatly exceeded the decay heat. As for pre-heaters, effective capacity was less than the heat loss. Therefore, the temperature of the reactor vessel room was raised to reduce the heat loss. One-loop operation of the PHTS was able to be executed by means of these measures. The cost of electrical consumption in the power plant has been reduced by one-loop operation of the PHTS and the modification period was shortened. (authors)

Conformation and stability of intramolecular telomeric G-quadruplexes: sequence effects in the loops.

Directory of Open Access Journals (Sweden)

Giovanna Sattin

Full Text Available Telomeres are guanine-rich sequences that protect the ends of chromosomes. These regions can fold into G-quadruplex structures and their stabilization by G-quadruplex ligands has been employed as an anticancer strategy. Genetic analysis in human telomeres revealed extensive allelic variation restricted to loop bases, indicating that the variant telomeric sequences maintain the ability to fold into G-quadruplex. To assess the effect of mutations in loop bases on G-quadruplex folding and stability, we performed a comprehensive analysis of mutant telomeric sequences by spectroscopic techniques, molecular dynamics simulations and gel electrophoresis. We found that when the first position in the loop was mutated from T to C or A the resulting structure adopted a less stable antiparallel topology; when the second position was mutated to C or A, lower thermal stability and no evident conformational change were observed; in contrast, substitution of the third position from A to C induced a more stable and original hybrid conformation, while mutation to T did not significantly affect G-quadruplex topology and stability. Our results indicate that allelic variations generate G-quadruplex telomeric structures with variable conformation and stability. This aspect needs to be taken into account when designing new potential anticancer molecules.

Visualizing Infrared (IR) Spectroscopy with Computer Animation

Science.gov (United States)

Abrams, Charles B.; Fine, Leonard W.

1996-01-01

IR Tutor, an interactive, animated infrared (IR) spectroscopy tutorial has been developed for Macintosh and IBM-compatible computers. Using unique color animation, complicated vibrational modes can be introduced to beginning students. Rules governing the appearance of IR absorption bands become obvious because the vibrational modes can be visualized. Each peak in the IR spectrum is highlighted, and the animation of the corresponding normal mode can be shown. Students can study each spectrum stepwise, or click on any individual peak to see its assignment. Important regions of each spectrum can be expanded and spectra can be overlaid for comparison. An introduction to the theory of IR spectroscopy is included, making the program a complete instructional package. Our own success in using this software for teaching and research in both academic and industrial environments will be described. IR Tutor consists of three sections: (1) The 'Introduction' is a review of basic principles of spectroscopy. (2) 'Theory' begins with the classical model of a simple diatomic molecule and is expanded to include larger molecules by introducing normal modes and group frequencies. (3) 'Interpretation' is the heart of the tutorial. Thirteen IR spectra are analyzed in detail, covering the most important functional groups. This section features color animation of each normal mode, full interactivity, overlay of related spectra, and expansion of important regions. This section can also be used as a reference.

An experimental study of dislocation loop nucleation

International Nuclear Information System (INIS)

Bounaud, J.Y.; Leteurtre, J.

1975-01-01

The nucleation of dislocation loops is experimentally studied by observing the demixion of the Burgers vectors of dislocation loops nucleated in copper whiskers irradiated in flexion by fission fragments at room temperature. The demixion of Burgers vectors is observed by the dimensional effects of dislocation loops: after irradiation, the applied stress is removed; the whisker shows a residual strain that is due to loops because, after an annealing treatment to evaporate dislocation loops, each whisker recovers its initial straight shape. Everywhere along the whisker, the radius of curvature is measured and plotted vs the max. applied stress. Estimations of the interstitial and vacancy dislocation loop nuclei are derived [fr

Stem loop sequences specific to transposable element IS605 are found linked to lipoprotein genes in Borrelia plasmids.

Directory of Open Access Journals (Sweden)

Nicholas Delihas

Full Text Available BACKGROUND: Plasmids of Borrelia species are dynamic structures that contain a large number of repetitive genes, gene fragments, and gene fusions. In addition, the transposable element IS605/200 family, as well as degenerate forms of this IS element, are prevalent. In Helicobacter pylori, flanking regions of the IS605 transposase gene contain sequences that fold into identical small stem loops. These function in transposition at the single-stranded DNA level. METHODOLOGY/PRINCIPAL FINDINGS: In work reported here, bioinformatics techniques were used to scan Borrelia plasmid genomes for IS605 transposable element specific stem loop sequences. Two variant stem loop motifs are found in the left and right flanking regions of the transposase gene. Both motifs appear to have dispersed in plasmid genomes and are found "free-standing" and phylogenetically conserved without the associated IS605 transposase gene or the adjacent flanking sequence. Importantly, IS605 specific stem loop sequences are also found at the 3' ends of lipoprotein genes (PFam12 and PFam60, however the left and right sequences appear to develop their own evolutionary patterns. The lipoprotein gene-linked left stem loop sequences maintain the IS605 stem loop motif in orthologs but only at the RNA level. These show mutations whereby variants fold into phylogenetically conserved RNA-type stem loops that contain the wobble non-Watson-Crick G-U base-pairing. The right flanking sequence is associated with the family lipoprotein-1 genes. A comparison of homologs shows that the IS605 stem loop motif rapidly dissipates, but a more elaborate secondary structure appears to develop in its place. CONCLUSIONS/SIGNIFICANCE: Stem loop sequences specific to the transposable element IS605 are present in plasmid regions devoid of a transposase gene and significantly, are found linked to lipoprotein genes in Borrelia plasmids. These sequences are evolutionarily conserved and/or structurally developed in

Assessing catchment connectivity using hysteretic loops

Science.gov (United States)

Davis, Jason; Masselink, Rens; Goni, Mikel; Gimenez, Rafael; Casali, Javier; Seeger, Manuel; Keesstra, Saskia

2017-04-01

Storm events mobilize large proportions of sediments in catchment systems. Therefore understanding catchment sediment dynamics throughout the continuity of storms and how initial catchment states act as controls on the transport of sediment to catchment outlets is important for effective catchment management. Sediment connectivity is a concept which can explain the origin, pathways and sinks of sediments within catchments (Baartman et al., 2013; Parsons et al., 2015; Masselink et al., 2016a,b; Mekonnen et al., 2016). However, sediment connectivity alone does not provide a practicable mechanism by which the catchment's initial state - and thus the location of entrained sediment in the sediment transport cascade - can be characterized. Studying the dynamic relationship between water discharge (Q) and suspended sediment (SS) at the catchment outlet can provide a valuable research tool to infer the likely source areas and flow pathways contributing to sediment transport because the relationship can be characterized by predictable hysteresis patterns. Hysteresis is observed when the sediment concentration associated with a certain flow rate is different depending on the direction in which the analysis is performed - towards the increase or towards the diminution of the flow. However, the complexity of the phenomena and factors which determine the hysteresis make its interpretation ambiguous. Previous work has described various types of hysteretic loops as well as the cause for the shape of the loop, mainly pointing to the origin of the sediments. The data set for this study comes from four experimental watersheds in Navarre (Spain), owned and maintained by the Government of Navarre. These experimental watersheds have been monitored and studied since 1996 (La Tejería and Latxaga) and 2001 (Oskotz principal and Oskotz woodland). La Tejería and Latxaga watersheds are similar to each other regarding size (approximately 200 ha), geology (marls and sandstones), soils (fine

Coupling between feedback loops in autoregulatory networks affects bistability range, open-loop gain and switching times

International Nuclear Information System (INIS)

Tiwari, Abhinav; Igoshin, Oleg A

2012-01-01

Biochemical regulatory networks governing diverse cellular processes such as stress-response, differentiation and cell cycle often contain coupled feedback loops. We aim at understanding how features of feedback architecture, such as the number of loops, the sign of the loops and the type of their coupling, affect network dynamical performance. Specifically, we investigate how bistability range, maximum open-loop gain and switching times of a network with transcriptional positive feedback are affected by additive or multiplicative coupling with another positive- or negative-feedback loop. We show that a network's bistability range is positively correlated with its maximum open-loop gain and that both quantities depend on the sign of the feedback loops and the type of feedback coupling. Moreover, we find that the addition of positive feedback could decrease the bistability range if we control the basal level in the signal-response curves of the two systems. Furthermore, the addition of negative feedback has the capacity to increase the bistability range if its dissociation constant is much lower than that of the positive feedback. We also find that the addition of a positive feedback to a bistable network increases the robustness of its bistability range, whereas the addition of a negative feedback decreases it. Finally, we show that the switching time for a transition from a high to a low steady state increases with the effective fold change in gene regulation. In summary, we show that the effect of coupled feedback loops on the bistability range and switching times depends on the underlying mechanistic details. (paper)

Gauge theory loop operators and Liouville theory

Energy Technology Data Exchange (ETDEWEB)

Drukker, Nadav [Humboldt Univ. Berlin (Germany). Inst. fuer Physik; Gomis, Jaume; Okuda, Takuda [Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada); Teschner, Joerg [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2009-10-15

We propose a correspondence between loop operators in a family of four dimensional N=2 gauge theories on S{sup 4} - including Wilson, 't Hooft and dyonic operators - and Liouville theory loop operators on a Riemann surface. This extends the beautiful relation between the partition function of these N=2 gauge theories and Liouville correlators found by Alday, Gaiotto and Tachikawa. We show that the computation of these Liouville correlators with the insertion of a Liouville loop operator reproduces Pestun's formula capturing the expectation value of a Wilson loop operator in the corresponding gauge theory. We prove that our definition of Liouville loop operators is invariant under modular transformations, which given our correspondence, implies the conjectured action of S-duality on the gauge theory loop operators. Our computations in Liouville theory make an explicit prediction for the exact expectation value of 't Hooft and dyonic loop operators in these N=2 gauge theories. The Liouville loop operators are also found to admit a simple geometric interpretation within quantum Teichmueller theory as the quantum operators representing the length of geodesics. We study the algebra of Liouville loop operators and show that it gives evidence for our proposal as well as providing definite predictions for the operator product expansion of loop operators in gauge theory. (orig.)

Role of IRS-2 in insulin and cytokine signalling.

Science.gov (United States)

Sun, X J; Wang, L M; Zhang, Y; Yenush, L; Myers, M G; Glasheen, E; Lane, W S; Pierce, J H; White, M F

1995-09-14

The protein IRS-1 acts as an interface between signalling proteins with Src-homology-2 domains (SH2 proteins) and the receptors for insulin, IGF-1, growth hormone, several interleukins (IL-4, IL-9, IL-13) and other cytokines. It regulates gene expression and stimulates mitogenesis, and appears to mediate insulin/IGF-1-stimulated glucose transport. Thus, survival of the IRS-1-/- mouse with only mild resistance to insulin was surprising. This dilemma is provisionally resolved with our discovery of a second IRS-signalling protein. We purified and cloned a likely candidate called 4PS from myeloid progenitor cells and, because of its resemblance to IRS-1, we designate it IRS-2. Alignment of the sequences of IRS-2 and IRS-1 revealed a highly conserved amino terminus containing a pleckstrin-homology domain and a phosphotyrosine-binding domain, and a poorly conserved carboxy terminus containing several tyrosine phosphorylation motifs. IRS-2 is expressed in many cells, including tissues from IRS-1-/- mice, and may be essential for signalling by several receptor systems.

Relating loop quantum cosmology to loop quantum gravity: symmetric sectors and embeddings

International Nuclear Information System (INIS)

Engle, J

2007-01-01

In this paper we address the meaning of states in loop quantum cosmology (LQC), in the context of loop quantum gravity. First, we introduce a rigorous formulation of an embedding proposed by Bojowald and Kastrup, of LQC states into loop quantum gravity. Then, using certain holomorphic representations, a new class of embeddings, called b-embeddings, are constructed, following the ideas of Engle (2006 Quantum field theory and its symmetry reduction Class. Quantum Gravity 23 2861-94). We exhibit a class of operators preserving each of these embeddings, and show their consistency with the LQC quantization. In the b-embedding case, the classical analogues of these operators separate points in phase space. Embedding at the gauge and diffeomorphism invariant level is discussed briefly in the conclusions

DNA looping by FokI: the impact of twisting and bending rigidity on protein-induced looping dynamics

Science.gov (United States)

Laurens, Niels; Rusling, David A.; Pernstich, Christian; Brouwer, Ineke; Halford, Stephen E.; Wuite, Gijs J. L.

2012-01-01

Protein-induced DNA looping is crucial for many genetic processes such as transcription, gene regulation and DNA replication. Here, we use tethered-particle motion to examine the impact of DNA bending and twisting rigidity on loop capture and release, using the restriction endonuclease FokI as a test system. To cleave DNA efficiently, FokI bridges two copies of an asymmetric sequence, invariably aligning the sites in parallel. On account of the fixed alignment, the topology of the DNA loop is set by the orientation of the sites along the DNA. We show that both the separation of the FokI sites and their orientation, altering, respectively, the twisting and the bending of the DNA needed to juxtapose the sites, have profound effects on the dynamics of the looping interaction. Surprisingly, the presence of a nick within the loop does not affect the observed rigidity of the DNA. In contrast, the introduction of a 4-nt gap fully relaxes all of the torque present in the system but does not necessarily enhance loop stability. FokI therefore employs torque to stabilise its DNA-looping interaction by acting as a ‘torsional’ catch bond. PMID:22373924

A closed-loop system for frequency tracking of piezoresistive cantilever sensors

Science.gov (United States)

Wasisto, Hutomo Suryo; Zhang, Qing; Merzsch, Stephan; Waag, Andreas; Peiner, Erwin

2013-05-01

A closed loop circuit capable of tracking resonant frequencies for MEMS-based piezoresistive cantilever resonators is developed in this work. The proposed closed-loop system is mainly based on a phase locked loop (PLL) circuit. In order to lock onto the resonant frequency of the resonator, an actuation signal generated from a voltage-controlled oscillator (VCO) is locked to the phase of the input reference signal of the cantilever sensor. In addition to the PLL component, an instrumentation amplifier and an active low pass filter (LPF) are connected to the system for gaining the amplitude and reducing the noise of the cantilever output signals. The LPF can transform a rectangular signal into a sinusoidal signal with voltage amplitudes ranging from 5 to 10 V which are sufficient for a piezoactuator input (i.e., maintaining a large output signal of the cantilever sensor). To demonstrate the functionality of the system, a self-sensing silicon cantilever resonator with a built-in piezoresistive Wheatstone bridge is fabricated and integrated with the circuit. A piezoactuator is utilized for actuating the cantilever into resonance. Implementation of this closed loop system is used to track the resonant frequency of a silicon cantilever-based sensor resonating at 9.4 kHz under a cross-sensitivity test of ambient temperature. The changes of the resonant frequency are interpreted using a frequency counter connected to the system. From the experimental results, the temperature sensitivity and coefficient of the employed sensor are 0.3 Hz/°C and 32.8 ppm/°C, respectively. The frequency stability of the system can reach up to 0.08 Hz. The development of this system will enable real-time nanoparticle monitoring systems and provide a miniaturization of the instrumentation modules for cantilever-based nanoparticle detectors.

NaIrO3-A pentavalent post-perovskite

International Nuclear Information System (INIS)

Bremholm, M.; Dutton, S.E.; Stephens, P.W.; Cava, R.J.

2011-01-01

Sodium iridium (V) oxide, NaIrO 3, was synthesized by a high pressure solid state method and recovered to ambient conditions. It is found to be isostructural with CaIrO 3 , the much-studied structural analog of the high-pressure post-perovskite phase of MgSiO 3 . Among the oxide post-perovskites, NaIrO 3 is the first example with a pentavalent cation. The structure consists of layers of corner- and edge-sharing IrO 6 octahedra separated by layers of NaO 8 bicapped trigonal prisms. NaIrO 3 shows no magnetic ordering and resistivity measurements show non-metallic behavior. The crystal structure, electrical and magnetic properties are discussed and compared to known post-perovskites and pentavalent perovskite metal oxides. -- Graphical abstract: Sodium iridium(V) oxide, NaIrO 3 , synthesized by a high pressure solid state method and recovered to ambient conditions is found to crystallize as the post-perovskite structure and is the first example of a pentavalent ABO 3 post-perovskite. Research highlights: → NaIrO 3 post-perovskite stabilized by pressure. → First example of a pentavalent oxide post-perovskite. → Non-metallic and non-magnetic behavior of NaIrO 3 .

Water loop for training

International Nuclear Information System (INIS)

Moeller, S.V.

1983-02-01

The procedures used to operate the water loop of the Institute of Nuclear Enginering (IEN) in Brazil are presented. The aim is to help future operators of the training water loop in the operation technique and in a better comprehension of the phenomena occured during the execution of an experience. (E.G.) [pt

The OregonHeart Total Artificial Heart: Design and Performance on a Mock Circulatory Loop.

Science.gov (United States)

Glynn, Jeremy; Song, Howard; Hull, Bryan; Withers, Stanley; Gelow, Jill; Mudd, James; Starr, Albert; Wampler, Richard

2017-10-01

Widespread use of heart transplantation is limited by the scarcity of donor organs. Total artificial heart (TAH) development has been pursued to address this shortage, especially to treat patients who require biventricular support. We have developed a novel TAH that utilizes a continuously spinning rotor that shuttles between two positions to provide pulsatile, alternating blood flow to the systemic and pulmonary circulations without artificial valves. Flow rates and pressures generated by the TAH are controlled by adjusting rotor speed, cycle frequency, and the proportion of each cycle spent pumping to either circulation. To validate the design, a TAH prototype was placed in a mock circulatory loop that simulates vascular resistance, pressure, and compliance in normal and pathophysiologic conditions. At a systemic blood pressure of 120/80 mm Hg, nominal TAH output was 7.4 L/min with instantaneous flows reaching 17 L/min. Pulmonary artery, and left and right atrial pressures were all maintained within normal ranges. To simulate implant into a patient with severe pulmonary hypertension, the pulmonary vascular resistance of the mock loop was increased to 7.5 Wood units. By increasing pump speed to the pulmonary circulation, cardiac output could be maintained at 7.4 L/min as mean pulmonary artery pressure increased to 56 mm Hg while systemic blood pressures remained normal. This in vitro testing of a novel, shuttling TAH demonstrated that cardiac output could be maintained across a range of pathophysiologic conditions including pulmonary hypertension. These experiments serve as a proof-of-concept for the design, which has proceeded to in vivo testing. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

How to remedy Eurocentrism in IR?

DEFF Research Database (Denmark)

Bilgin, Pinar

2016-01-01

While IR's Eurocentric limits are usually acknowledged, what those limits mean for theorizing about the international is seldom clarified. In The Global Transformation, Buzan and Lawson offer a 'composite approach' that goes some way towards addressing IR's Eurocentrism, challenging existing myth...

LHX2 Mediates the FGF-to-SHH Regulatory Loop during Limb Development

Directory of Open Access Journals (Sweden)

Billy A. Watson

2018-06-01

Full Text Available During limb development, fibroblast growth factors (Fgfs govern proximal–distal outgrowth and patterning. FGFs also synchronize developmental patterning between the proximal–distal and anterior–posterior axes by maintaining Sonic hedgehog (Shh expression in cells of the zone of polarizing activity (ZPA in the distal posterior mesoderm. Shh, in turn, maintains Fgfs in the apical ectodermal ridge (AER that caps the distal tip of the limb bud. Crosstalk between Fgf and Shh signaling is critical for patterned limb development, but the mechanisms underlying this feedback loop are not well-characterized. Implantation of Fgf beads in the proximal posterior limb bud can maintain SHH expression in the former ZPA domain (evident 3 h after application, while prolonged exposure (24 h can induce SHH outside of this domain. Although temporally and spatially disparate, comparative analysis of transcriptome data from these different populations accentuated genes involved in SHH regulation. Comparative analysis identified 25 candidates common to both treatments, with eight linked to SHH expression or function. Furthermore, we demonstrated that LHX2, a LIM Homeodomain transcription factor, is an intermediate in the FGF-mediated regulation of SHH. Our data suggest that LHX2 acts as a competency factor maintaining distal posterior SHH expression subjacent to the AER.

Endurance test on IR rig for RI production

International Nuclear Information System (INIS)

Chung, Heung June; Youn, Y. J.; Han, H. S.; Hong, S. B.; Cho, Y. G.; Ryu, J. S.

2000-12-01

This report presents the pressure drop, vibration and endurance test results for IR rig for RI production which were desigened and fabricated by KAERI. From the pressure drop test results, it is noted that the flow rate through the IR rig corresponding to the pressure drop of 200 kPa is measured to be about 3.12 kg/sec. Vibration frequency for the IR rig ranges from 13 to 17 Hz. RMS(Root Mean Square) displacement for the IR rig is less than 30 μm, and the maximum displacement is less than 110μm. These experimental results show that the design criteria of IR rig meet the HANARO limit conditions. Endurance test results show that the appreciable fretting wear for the IR rig does not occur, however tiny trace of wear between contact points is observed

Study on IR Properties of Reduced Graphene Oxide

Science.gov (United States)

Ma, Deyue; Li, Xiaoxia; Guo, Yuxiang; Zeng, Yurun

2018-01-01

Firstly, the reduced graphene oxide was prepared by modified hummer method and characterized. Then, the complex refractive index of reduced graphene oxide in IR band was tested and its IR absorption and radiation properties were researched by correlated calculation. The results show that reduced graphene oxide prepared by hummer method are multilayered graphene with defects and functional groups on its surface. Its absorption in near and far IR bands is strong, but it’s weaker in middle IR band. At the IR atmosphere Window, its normal spectral emissivity decreases with wavelength increasing, and its total normal spectral emissivity in 3 ∼ 5μm and 8 ∼ 14μm are 0.75 and 0.625, respectively. Therefore, reduced graphene oxide can be used as IR absorption and coating materials and have a great potential in microwave and infrared compatible materials.

Use of HOMA-IR in hepatitis C.

Science.gov (United States)

Eslam, M; Kawaguchi, T; Del Campo, J A; Sata, M; Khattab, M Abo-Elneen; Romero-Gomez, M

2011-10-01

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent manner and contributes to steatosis, progression of fibrosis and resistance to interferon plus ribavirin therapy. Our understanding of HCV-induced IR has improved considerably over the years, but certain aspects concerning its evaluation still remain elusive to clinical researchers. One of the most important issues is elucidating the ideal method for assessment of IR in the setting of hepatitis C. The hyperinsulinaemic euglycaemic clamp is the gold standard method for determining insulin sensitivity, but is impractical as it is labour intensive and time-consuming. To date, all human studies except for four where IR was evaluated in the HCV setting, an estimation of IR has been used rather than direct measurements of insulin-mediated glucose uptake. The most commonly used estimation in the HCV population is the homeostasis model assessment of insulin resistance (HOMA-IR) which is calculated from a single measurement of fasting insulin and glucose. In this article, we review the use and reporting of HOMA in the literature and provide guidance on its appropriate as well as inappropriate use in the hepatitis setting. © 2011 Blackwell Publishing Ltd.

Loop equations in the theory of gravitation

International Nuclear Information System (INIS)

Makeenko, Yu.M.; Voronov, N.A.

1981-01-01

Loop-space variables (matrices of parallel transport) for the theory of gravitation are described. Loop equations, which are equivalent to the Einstein equations, are derived in the classical case. Loop equations are derived for gravity with cosmological constant as well. An analogy with the loop-space approach in Yang-Mills theory is discussed [ru

Tritium Management Loop Design Status

Energy Technology Data Exchange (ETDEWEB)

Rader, Jordan D. [ORNL; Felde, David K. [ORNL; McFarlane, Joanna [ORNL; Greenwood, Michael Scott [ORNL; Qualls, A L. [ORNL; Calderoni, Pattrick [Idaho National Laboratory (INL)

2017-12-01

This report summarizes physical, chemical, and engineering analyses that have been done to support the development of a test loop to study tritium migration in 2LiF-BeF2 salts. The loop will operate under turbulent flow and a schematic of the apparatus has been used to develop a model in Mathcad to suggest flow parameters that should be targeted in loop operation. The introduction of tritium into the loop has been discussed as well as various means to capture or divert the tritium from egress through a test assembly. Permeation was calculated starting with a Modelica model for a transport through a nickel window into a vacuum, and modifying it for a FLiBe system with an argon sweep gas on the downstream side of the permeation interface. Results suggest that tritium removal with a simple tubular permeation device will occur readily. Although this system is idealized, it suggests that rapid measurement capability in the loop may be necessary to study and understand tritium removal from the system.

Criteria for saturated magnetization loop

International Nuclear Information System (INIS)

Harres, A.; Mikhov, M.; Skumryev, V.; Andrade, A.M.H. de; Schmidt, J.E.; Geshev, J.

2016-01-01

Proper estimation of magnetization curve parameters is vital in studying magnetic systems. In the present article, criteria for discrimination non-saturated (minor) from saturated (major) hysteresis loops are proposed. These employ the analysis of (i) derivatives of both ascending and descending branches of the loop, (ii) remanent magnetization curves, and (iii) thermomagnetic curves. Computational simulations are used in order to demonstrate their validity. Examples illustrating the applicability of these criteria to well-known real systems, namely Fe_3O_4 and Ni fine particles, are provided. We demonstrate that the anisotropy-field value estimated from a visual examination of an only apparently major hysteresis loop could be more than two times lower than the real one. - Highlights: • Proper estimation of hysteresis-loop parameters is vital in magnetic studies. • We propose criteria for discrimination minor from major hysteresis loops. • The criteria analyze magnetization, remanence and ZFC/FC curves and/or their derivatives. • Examples of their application on real nanoparticles systems are given. • Using the criteria could avoid twofold or bigger saturation-field underestimation errors.

Criteria for saturated magnetization loop

Energy Technology Data Exchange (ETDEWEB)

Harres, A. [Departamento de Física, UFSM, Santa Maria, 97105-900 Rio Grande do Sul (Brazil); Mikhov, M. [Faculty of Physics, University of Sofia, 1164 Sofia (Bulgaria); Skumryev, V. [Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona (Spain); Departament de Física, Universitat Autònoma de Barcelona, 08193 Barcelona (Spain); Andrade, A.M.H. de; Schmidt, J.E. [Instituto de Física, UFRGS, Porto Alegre, 91501-970 Rio Grande do Sul (Brazil); Geshev, J., E-mail: julian@if.ufrgs.br [Departament de Física, Universitat Autònoma de Barcelona, 08193 Barcelona (Spain); Instituto de Física, UFRGS, Porto Alegre, 91501-970 Rio Grande do Sul (Brazil)

2016-03-15

Proper estimation of magnetization curve parameters is vital in studying magnetic systems. In the present article, criteria for discrimination non-saturated (minor) from saturated (major) hysteresis loops are proposed. These employ the analysis of (i) derivatives of both ascending and descending branches of the loop, (ii) remanent magnetization curves, and (iii) thermomagnetic curves. Computational simulations are used in order to demonstrate their validity. Examples illustrating the applicability of these criteria to well-known real systems, namely Fe{sub 3}O{sub 4} and Ni fine particles, are provided. We demonstrate that the anisotropy-field value estimated from a visual examination of an only apparently major hysteresis loop could be more than two times lower than the real one. - Highlights: • Proper estimation of hysteresis-loop parameters is vital in magnetic studies. • We propose criteria for discrimination minor from major hysteresis loops. • The criteria analyze magnetization, remanence and ZFC/FC curves and/or their derivatives. • Examples of their application on real nanoparticles systems are given. • Using the criteria could avoid twofold or bigger saturation-field underestimation errors.

Hermann agreement updates IRS guidelines for incentives.

Science.gov (United States)

Broccolo, B M; Peregrine, M W

1995-01-01

The October 1994 agreement between the Internal Revenue Service (IRS) and Hermann Hospital of Houston, Texas, elucidates current IRS policy on physician recruitment incentives. The IRS distinguishes between the recruiting and the retention of physicians and perimts incentives beyond reasonable compensation in the former but not the latter circumstance. This new agreement, while not legally precedential, nevertheless provides guidance for healthcare organizations seeking safe harbor protection.

Capillary-Condenser-Pumped Heat-Transfer Loop

Science.gov (United States)

Silverstein, Calvin C.

1989-01-01

Heat being transferred supplies operating power. Capillary-condenser-pumped heat-transfer loop similar to heat pipe and to capillary-evaporator-pumped heat-transfer loop in that heat-transfer fluid pumped by evaporation and condensation of fluid at heat source and sink, respectively. Capillary condenser pump combined with capillary evaporator pump to form heat exchanger circulating heat-transfer fluids in both loops. Transport of heat more nearly isothermal. Thermal stress in loop reduced, and less external surface area needed in condenser section for rejection of heat to heat sink.

Quantum chromodynamics as dynamics of loops

International Nuclear Information System (INIS)

Makeenko, Yu.; Migdal, A.A.

1980-01-01

The problem of a possibility of reformulating quantum chromodynamics (QCD) in terms of colourless composite fields instead of coloured quarks and gluons is considered. The role of such fields is played by the gauge invariant loop functionals. The Shwinger equations of motion is derived in the loop space which completely describe dynamics of the loop fields. New manifestly gauge invariant diagram technique in the loop space is developed. These diagrams reproduce asymptotic freedom in the ultraviolet range and are consistent with the confinement law in the infrared range

Persistent semi-metal-like nature of epitaxial perovskite CaIrO{sub 3} thin films

Energy Technology Data Exchange (ETDEWEB)

Biswas, Abhijit; Jeong, Yoon Hee, E-mail: yhj@postech.ac.kr [Department of Physics, POSTECH, Pohang 790-784 (Korea, Republic of)

2015-05-21

Strong spin-orbit coupled 5d transition metal based ABO{sub 3} oxides, especially iridates, allow tuning parameters in the phase diagram and may demonstrate important functionalities, for example, by means of strain effects and symmetry-breaking, because of the interplay between the Coulomb interactions and strong spin-orbit coupling. Here, we have epitaxially stabilized high quality thin films of perovskite (Pv) CaIrO{sub 3}. Film on the best lattice-matched substrate shows semi-metal-like characteristics. Intriguingly, imposing tensile or compressive strain on the film by altering the underlying lattice-mismatched substrates still maintains semi-metallicity with minute modification of the effective correlation as tensile (compressive) strain results in tiny increases (decreases) of the electronic bandwidth. In addition, magnetoresistance remains positive with a quadratic field dependence. This persistent semi-metal-like nature of Pv-CaIrO{sub 3} thin films with minute changes in the effective correlation by strain may provide new wisdom into strong spin-orbit coupled 5d based oxide physics.

Abnormal duodenal loop demonstrated by X-ray

International Nuclear Information System (INIS)

Thommesen, P.; Funch-Jensen, P.

1986-01-01

The occurrence of dyspeptic symptoms has previously been correlated with the shape of the duodenal loop in patients with X-ray-negative dyspepsia. An abnormal duodenal loop was associated with a significantly higher incidence of symtoms provoked by meals, vomiting, regurgitations, heartburn, and the irritable bowel syndrome. 89% of these patients (26 patients with a normal duodenal loop and 39 patients with abnormal duodenal loop) were available for a 5-year follow-up study of symptomatic outcome. The incidence of symptoms provoked by meals was still significantly higher in patients with an abnormal duodenal loop, and there was also a significant difference concerning symptomatic outcome. Approximately 75% of the patients with a normal duodenal loop had improved, and 25% had unchanged clinical conditions. Approximately 50% of the patients with an abnormal duodenal loop had improved, and 50% had an unchanged or even deteriorated clinical condition

Kalman Orbit Optimized Loop Tracking

Science.gov (United States)

Young, Lawrence E.; Meehan, Thomas K.

2011-01-01

Under certain conditions of low signal power and/or high noise, there is insufficient signal to noise ratio (SNR) to close tracking loops with individual signals on orbiting Global Navigation Satellite System (GNSS) receivers. In addition, the processing power available from flight computers is not great enough to implement a conventional ultra-tight coupling tracking loop. This work provides a method to track GNSS signals at very low SNR without the penalty of requiring very high processor throughput to calculate the loop parameters. The Kalman Orbit-Optimized Loop (KOOL) tracking approach constitutes a filter with a dynamic model and using the aggregate of information from all tracked GNSS signals to close the tracking loop for each signal. For applications where there is not a good dynamic model, such as very low orbits where atmospheric drag models may not be adequate to achieve the required accuracy, aiding from an IMU (inertial measurement unit) or other sensor will be added. The KOOL approach is based on research JPL has done to allow signal recovery from weak and scintillating signals observed during the use of GPS signals for limb sounding of the Earth s atmosphere. That approach uses the onboard PVT (position, velocity, time) solution to generate predictions for the range, range rate, and acceleration of the low-SNR signal. The low- SNR signal data are captured by a directed open loop. KOOL builds on the previous open loop tracking by including feedback and observable generation from the weak-signal channels so that the MSR receiver will continue to track and provide PVT, range, and Doppler data, even when all channels have low SNR.

Direct phase-locking of a 8.6-μm quantum cascade laser to a mid-IR optical frequency comb: application to precision spectroscopy of N2O.

Science.gov (United States)

Gambetta, Alessio; Cassinerio, Marco; Coluccelli, Nicola; Fasci, Eugenio; Castrillo, Antonio; Gianfrani, Livio; Gatti, Davide; Marangoni, Marco; Laporta, Paolo; Galzerano, Gianluca

2015-02-01

We developed a high-precision spectroscopic system at 8.6 μm based on direct heterodyne detection and phase-locking of a room-temperature quantum-cascade-laser against an harmonic, 250-MHz mid-IR frequency comb obtained by difference-frequency generation. The ∼30  dB signal-to-noise ratio of the detected beat-note together with the achieved closed-loop locking bandwidth of ∼500  kHz allows for a residual integrated phase noise of 0.78 rad (1 Hz-5 MHz), for an ultimate resolution of ∼21  kHz, limited by the measured linewidth of the mid-IR comb. The system was used to perform absolute measurement of line-center frequencies for the rotational components of the ν2 vibrational band of N2O, with a relative precision of 3×10(-10).

LOOP: engineering marvel, economic calamity

Energy Technology Data Exchange (ETDEWEB)

Brossard, E B

1985-01-01

The Louisiana Offshore Oil Port (LOOP) is the first superport built in the Lower 48. The United States was the only major oil-importing country that did not have a superport, and therefore, could not offload very large crude carriers (VLCCs). Unfortunately, a number of factors changed after it was decided to build LOOP, and these, plus the onerous provisions of the Deepwater Ports Act of 1974, which authorized superports, prevented LOOP from operating economically. LOOP's facilities consist of an offshore platform complex with three single-point-mooring (SPM) system buoys, 19 miles offshore in 110 feet of water, as well as a 32-million-barrel storage terminal 31 miles inland at Clovelly Salt Dome, and connecting pipelines offshore and onshore. By the time LOOP was started-up in May 1981, demand for oil had declined, because of rises in the price of oil, and the source of US oil imports had shifted back to the western hemisphere, away from the eastern hemisphere, closer to the US. The refinery mix in the US also changed, because of up-grading of a number of big refineries, which further reduced demand and made heavier crudes from countries like Mexico and Venezuela more economical. Because of reduced oil imports and shorter hauls, oil shippers started using or continued to use smaller tankers. Smaller tankers are not economical for LOOP, nor do they need LOOP. The start-up of the Trans-Alaska Pipeline System (TAPS) in mid-1977 backed out 1.5 million bd/sup -1/ of foreign imports. TAPS' capacity coincides with LOOP's offloading capacity of 1.4 million bd/sup -1/. US decontrol of domestic crude in 1981 and increased drilling, plus general energy conservation further reduced US oil imports. US consumption declined to 15.1 million bd/sup -1/ in 1983, from 18.8 million bd/sup -1/ in 1978. This award-winning superport needed federal decontrol and increased oil imports along with more VLCCs, in order to operate economically.

Design and Development of transducer for IR radiation measurement

International Nuclear Information System (INIS)

Pattarachindanuwong, Surat; Poopat, Bovornchoke; Meethong, Wachira

2003-06-01

Recently, IR radiation has many important roles such as for plastics industry, food industry and medical instrumentation. The consequence of exposed irradiation objects from IR can be greatly affected by the quantity of IR radiation. Therefore the objectively this research is to design and develop a transducer for IR radiation measurement. By using a quartz halogen lamp as a IR heat source of IR radiation and a thermopile sensor as a transducer. The thermal conductivity of transducer and air flow, were also considered for design and development of transducer. The study shows that the designed transducer can be used and applied in high temperature process, for example, the quality control of welding, the non-contact temperature measurement of drying oven and the testing of IR source in medical therapy device

The massless two-loop two-point function

International Nuclear Information System (INIS)

Bierenbaum, I.; Weinzierl, S.

2003-01-01

We consider the massless two-loop two-point function with arbitrary powers of the propagators and derive a representation from which we can obtain the Laurent expansion to any desired order in the dimensional regularization parameter ε. As a side product, we show that in the Laurent expansion of the two-loop integral only rational numbers and multiple zeta values occur. Our method of calculation obtains the two-loop integral as a convolution product of two primitive one-loop integrals. We comment on the generalization of this product structure to higher loop integrals. (orig.)

Open loop thanks to direct torque control (DTC). Motor control without feedback loop; Open loop dank direkter Drehmomentregelung (DTC). Hochwertige Motorregelung ohne Rueckfuehrung

Energy Technology Data Exchange (ETDEWEB)

Link, Michael [ABB Automation Products GmbH, Ladenburg (Germany)

2009-07-01

Servo drives are used in various applications. The range of applications is huge and thus also requirements to the drive system. Mainly, a fast torque and speed control is required. This is the domaine of direct torque control (DTC). In many applications DTC can meet this challenge to control the motor with full torque at zero speed. The servo converter based on DTC technology provides a control concept for synchronous and asynchronous motors for both closed loop and open loop control. DTC controlled drives support the whole range from open loop up to high performance motion control applications. (orig.)

SH2-B promotes insulin receptor substrate 1 (IRS1)- and IRS2-mediated activation of the phosphatidylinositol 3-kinase pathway in response to leptin.

Science.gov (United States)

Duan, Chaojun; Li, Minghua; Rui, Liangyou

2004-10-15

Leptin regulates energy homeostasis primarily by binding and activating its long form receptor (LRb). Deficiency of either leptin or LRb causes morbid obesity. Leptin stimulates LRb-associated JAK2, thus initiating multiple pathways including the Stat3 and phosphatidylinositol (PI) 3-kinase pathways that mediate leptin biological actions. Here we report that SH2-B, a JAK2-interacting protein, promotes activation of the PI 3-kinase pathway by recruiting insulin receptor substrate 1 (IRS1) and IRS2 in response to leptin. SH2-B directly bound, via its PH and SH2 domain, to both IRS1 and IRS2 both in vitro and in intact cells and mediated formation of a JAK2/SH2-B/IRS1 or IRS2 tertiary complex. Consequently, SH2-B dramatically enhanced leptin-stimulated tyrosine phosphorylation of IRS1 and IRS2 in HEK293 cells stably expressing LRb, thus promoting association of IRS1 and IRS2 with the p85 regulatory subunit of PI 3-kinase and phosphorylation and activation of Akt. SH2-B mutants with lower affinity for IRS1 and IRS2 exhibited reduced ability to promote association of JAK2 with IRS1, tyrosine phosphorylation of IRS1, and association of IRS1 with p85 in response to leptin. Moreover, deletion of the SH2-B gene impaired leptin-stimulated tyrosine phosphorylation of endogenous IRS1 in mouse embryonic fibroblasts (MEF), which was reversed by reintroduction of SH2-B. Similarly, SH2-B promoted growth hormone-stimulated tyrosine phosphorylation of IRS1 in both HEK293 and MEF cells. Our data suggest that SH2-B is a novel mediator of the PI 3-kinase pathway in response to leptin or other hormones and cytokines that activate JAK2.

HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome - Brazilian Metabolic Syndrome Study (BRAMS)

OpenAIRE

Geloneze, B; Vasques, ACJ; Stabe, CFC; Pareja, JC; Rosado, LEFPD; de Queiroz, EC; Tambascia, MA

2009-01-01

Objective: To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Methods: Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 9011 percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. Results: In the he...

New Ir Bis-Carbonyl Precursor for Water Oxidation Catalysis

Energy Technology Data Exchange (ETDEWEB)

Huang, Daria L. [Department of Chemistry, Yale University, 225; Beltrán-Suito, Rodrigo [Department of Chemistry, Yale University, 225; Thomsen, Julianne M. [Department of Chemistry, Yale University, 225; Hashmi, Sara M. [Department of Chemical and Environmental; Materna, Kelly L. [Department of Chemistry, Yale University, 225; Sheehan, Stafford W. [Catalytic Innovations LLC, 70 Crandall; Mercado, Brandon Q. [Department of Chemistry, Yale University, 225; Brudvig, Gary W. [Department of Chemistry, Yale University, 225; Crabtree, Robert H. [Department of Chemistry, Yale University, 225

2016-02-05

This paper introduces IrI(CO)2(pyalc) (pyalc = (2-pyridyl)-2-propanoate) as an atom-efficient precursor for Ir-based homogeneous oxidation catalysis. This compound was chosen to simplify analysis of the water oxidation catalyst species formed by the previously reported Cp*IrIII(pyalc)OH water oxidation precatalyst. Here, we present a comparative study on the chemical and catalytic properties of these two precursors. Previous studies show that oxidative activation of Cp*Ir-based precursors with NaIO4 results in formation of a blue IrIV species. This activation is concomitant with the loss of the placeholder Cp* ligand which oxidatively degrades to form acetic acid, iodate, and other obligatory byproducts. The activation process requires substantial amounts of primary oxidant, and the degradation products complicate analysis of the resulting IrIV species. The species formed from oxidation of the Ir(CO)2(pyalc) precursor, on the other hand, lacks these degradation products (the CO ligands are easily lost upon oxidation) which allows for more detailed examination of the resulting Ir(pyalc) active species both catalytically and spectroscopically, although complete structural analysis is still elusive. Once Ir(CO)2(pyalc) is activated, the system requires acetic acid or acetate to prevent the formation of nanoparticles. Investigation of the activated bis-carbonyl complex also suggests several Ir(pyalc) isomers may exist in solution. By 1H NMR, activated Ir(CO)2(pyalc) has fewer isomers than activated Cp*Ir complexes, allowing for advanced characterization. Future research in this direction is expected to contribute to a better structural understanding of the active species. A diol crystallization agent was needed for the structure determination of 3.

Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

2017-12-13

A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Mid-Infrared Spectral Properties of IR QSOs

International Nuclear Information System (INIS)

Xia, X. Y.; Cao, C.; Mao, S.; Deng, Z. G.

2008-01-01

We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope. The MIR properties of IR QSOs are compared with those of optically-selected Palomar-Green QSOs (PG QSOs) and ultra-luminous infrared galaxies (ULIRGs). The average MIR spectral features from ∼5 to 30 μm, including the spectral slopes, 6.2 μm PAH emission strengths and [NeII] 12.81 μm luminosities of IR QSOs, differ from those of PG QSOs. In contrast, IR QSOs and ULIRGs have comparable PAH and [NeII] luminosities. These results are consistent with IR QSOs being at a transitional stage from ULIRGs to classical QSOs. We also find the correlation between the EW (PAH 6.2 μm) and outflow velocities suggests that star formation activities are suppressed by feedback from AGNs and/or supernovae.

IGF-IR targeted therapy: Past, present and future

NARCIS (Netherlands)

J.A.M.J.L. Janssen (Joseph); A.J. Varewijck (Aimee)

2014-01-01

textabstractThe IGF-I receptor (IGF-IR) has been studied as an anti-cancer target. However, monotherapy trials with IGF-IR targeted antibodies or with IGF-IR specific tyrosine kinase inhibitors have, overall, been very disappointing in the clinical setting. This review discusses potential reasons

Exchange bias properties of 140 nm-sized dipolarly interacting circular dots with ultrafine IrMn and NiFe layers

Energy Technology Data Exchange (ETDEWEB)

Spizzo, F., E-mail: spizzo@fe.infn.it [Dipartimento di Fisica e Scienze della Terra and CNISM, Università di Ferrara, I-44122 Ferrara (Italy); Tamisari, M. [Dipartimento di Fisica e Scienze della Terra and CNISM, Università di Ferrara, I-44122 Ferrara (Italy); Dipartimento di Fisica e Geologia and CNISM, Università di Perugia, I-06123 Perugia (Italy); Chinni, F.; Bonfiglioli, E. [Dipartimento di Fisica e Scienze della Terra and CNISM, Università di Ferrara, I-44122 Ferrara (Italy); Gerardino, A. [Istituto di Fotonica e Nanotecnologie, CNR, I-00156 Roma (Italy); Barucca, G. [Dipartimento SIMAU, Università Politecnica delle Marche, I-60131 Ancona (Italy); Bisero, D.; Fin, S.; Del Bianco, L. [Dipartimento di Fisica e Scienze della Terra and CNISM, Università di Ferrara, I-44122 Ferrara (Italy)

2016-02-15

We studied the exchange bias effect in an array of IrMn(3 nm)/NiFe(3 nm) circular dots (size ~140 nm and center-to-center distance ~200 nm, as revealed by microscopy analyses), prepared on a large area (3×3 mm{sup 2}) by electron beam lithography and lift-off, using dc sputtering deposition. Hysteresis loops were measured by SQUID magnetometer at increasing values of temperature T (in the 5–300 K range) after cooling from 300 K down to 5 K in zero field (ZFC mode) and in a saturating magnetic field (FC mode). The exchange bias effect disappears above T~200 K and, at each temperature, the exchange field H{sub EX} measured in ZFC is substantially lower than the FC one. Micromagnetic calculations indicate that, at room temperature, each dot is in high-remanence ground state, but magnetic dipolar interactions establish a low-remanence configuration of the array as a whole. Hence, at low temperature, following the ZFC procedure, the exchange anisotropy in the dot array is averaged out, tending to zero. However, even the FC values of H{sub EX} and of the coercivity H{sub C} are definitely smaller compared to those measured in a reference continuous film with the same stack configuration (at T=5 K, H{sub EX}~90 Oe and H{sub C}~180 Oe in the dots and H{sub EX}~1270 Oe and H{sub C}~860 Oe in the film). Our explanation is based on the proven glassy magnetic nature of the ultrathin IrMn layer, implying the existence of magnetic correlations among the spins, culminating in a collective freezing below T~100 K. We propose, also by the light of micromagnetic simulations, that the small dot size imposes a spatial constraint on the magnetic correlation length among the IrMn spins so that, even at the lowest temperature, their thermal stability, especially at the dot border, is compromised. - Highlights: • Exchange bias in 140 nm-sized IrMn(3 nm)/NiFe(3 nm) dots much weaker than in a film. • Glassy magnetic nature of the IrMn phase and collective spin freezing at T<100 K �

Exchange bias properties of 140 nm-sized dipolarly interacting circular dots with ultrafine IrMn and NiFe layers

International Nuclear Information System (INIS)

Spizzo, F.; Tamisari, M.; Chinni, F.; Bonfiglioli, E.; Gerardino, A.; Barucca, G.; Bisero, D.; Fin, S.; Del Bianco, L.

2016-01-01

We studied the exchange bias effect in an array of IrMn(3 nm)/NiFe(3 nm) circular dots (size ~140 nm and center-to-center distance ~200 nm, as revealed by microscopy analyses), prepared on a large area (3×3 mm"2) by electron beam lithography and lift-off, using dc sputtering deposition. Hysteresis loops were measured by SQUID magnetometer at increasing values of temperature T (in the 5–300 K range) after cooling from 300 K down to 5 K in zero field (ZFC mode) and in a saturating magnetic field (FC mode). The exchange bias effect disappears above T~200 K and, at each temperature, the exchange field H_E_X measured in ZFC is substantially lower than the FC one. Micromagnetic calculations indicate that, at room temperature, each dot is in high-remanence ground state, but magnetic dipolar interactions establish a low-remanence configuration of the array as a whole. Hence, at low temperature, following the ZFC procedure, the exchange anisotropy in the dot array is averaged out, tending to zero. However, even the FC values of H_E_X and of the coercivity H_C are definitely smaller compared to those measured in a reference continuous film with the same stack configuration (at T=5 K, H_E_X~90 Oe and H_C~180 Oe in the dots and H_E_X~1270 Oe and H_C~860 Oe in the film). Our explanation is based on the proven glassy magnetic nature of the ultrathin IrMn layer, implying the existence of magnetic correlations among the spins, culminating in a collective freezing below T~100 K. We propose, also by the light of micromagnetic simulations, that the small dot size imposes a spatial constraint on the magnetic correlation length among the IrMn spins so that, even at the lowest temperature, their thermal stability, especially at the dot border, is compromised. - Highlights: • Exchange bias in 140 nm-sized IrMn(3 nm)/NiFe(3 nm) dots much weaker than in a film. • Glassy magnetic nature of the IrMn phase and collective spin freezing at T<100 K • Confinement of IrMn magnetic

OGTT results in obese adolescents with normal HOMA-IR values.

Science.gov (United States)

Sahin, Nursel Muratoglu; Kinik, Sibel Tulgar; Tekindal, Mustafa Agah

2013-01-01

To investigate insulin resistance (IR) with OGTT in obese adolescents who have normal fasting insulin and homeostasis model assessment for insulin resistance (HOMA-IR). A total of 97 obese adolescents who had values of HOMA-IR IR using an insulin peak of ≥150 μU/mL (1041.8 pmol/L) and/or ≥75 μU/mL (520.9 pmol/L) 120 min after glucose charge and the sum of insulin levels >2083.5 pmol/L (300 μU/mL) in OGTT. IR risk factors were defined as family history of diabetes mellitus, acanthosis nigricans (AN), and hepatic steatosis. IR was detected in 61 (62.9%) patients. The IR group had significantly more frequent AN (p=0.0001). As the number of risk factors increased, the frequency of IR also increased (p=0.01). We advise to perform OGTT in obese adolescents with normal HOMA-IR, if they have risk factors for IR.

Stability, structure, and evolution of cool loops

International Nuclear Information System (INIS)

Cally, P.S.; Robb, T.D.

1991-01-01

The criteria for the existence and stability of cool loops are reexamined. It is found that the stability of the loops strongly depends on the form of the heating and radiative loss functions and that if the Ly-alpha peak which appears in most calculations of the radiative loss function is real, cool loops are almost certainly unstable. Removing the hydrogen contribution from the recent loss function Q(T) by Cook et al. (1989) does not produce the much-used result, Q proportional to T-cubed, which is so favorable to cool loop stability. Even using the probably unrealistically favorable loss function Q1 of Cook et al. with the hydrogen contribution removed, the maximum temperature attainable in stable cool loops is a factor of 2-3 too small to account for the excess emission observed in lower transition region lines. Dynamical simulations of cool loop instabilities reveal that the final state of such a model is the hot loop equilibrium. 26 refs

3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses

Directory of Open Access Journals (Sweden)

Kim Nammoon

2011-01-01

Full Text Available Abstract In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.

4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

Science.gov (United States)

Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

1995-10-20

Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

Conformal anomaly of super Wilson loop

Energy Technology Data Exchange (ETDEWEB)

Belitsky, A.V., E-mail: andrei.belitsky@asu.edu [Department of Physics, Arizona State University, Tempe, AZ 85287-1504 (United States)

2012-09-11

Classically supersymmetric Wilson loop on a null polygonal contour possesses all symmetries required to match it onto non-MHV amplitudes in maximally supersymmetric Yang-Mills theory. However, to define it quantum mechanically, one is forced to regularize it since perturbative loop diagrams are not well defined due to presence of ultraviolet divergences stemming from integration in the vicinity of the cusps. A regularization that is adopted by practitioners by allowing one to use spinor helicity formalism, on the one hand, and systematically go to higher orders of perturbation theory is based on a version of dimensional regularization, known as Four-Dimensional Helicity scheme. Recently it was demonstrated that its use for the super Wilson loop at one loop breaks both conformal symmetry and Poincare supersymmetry. Presently, we exhibit the origin for these effects and demonstrate how one can undo this breaking. The phenomenon is alike the one emerging in renormalization group mixing of conformal operators in conformal theories when one uses dimensional regularization. The rotation matrix to the diagonal basis is found by means of computing the anomaly in the Ward identity for the conformal boost. Presently, we apply this ideology to the super Wilson loop. We compute the one-loop conformal anomaly for the super Wilson loop and find that the anomaly depends on its Grassmann coordinates. By subtracting this anomalous contribution from the super Wilson loop we restore its interpretation as a dual description for reduced non-MHV amplitudes which are expressed in terms of superconformal invariants.

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high-capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit Transport Water Loop. The bed design further leverages a sorbent developed for the ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System. The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of crewed spaceflight Environmental Control and Life Support System hardware.

Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2013-01-01

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator

Science.gov (United States)

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2011-01-01

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a clear demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Fundamental and Harmonic Oscillations in Neighboring Coronal Loops

Science.gov (United States)

Li, Hongbo; Liu, Yu; Vai Tam, Kuan

2017-06-01

We present observations of multimode (fundamental and harmonic) oscillations in a loop system, which appear to be simultaneously excited by a GOES C-class flare. Analysis of the periodic oscillations reveals that (1) the primary loop with a period of P a ≈ 4 minutes and a secondary loop with two periods of P a ≈ 4 minutes and P b ≈ 2 minutes are detected simultaneously in closely spaced loop strands; (2) both oscillation components have their peak amplitudes near the loop apex, while in the second loop the low-frequency component P a dominates in a loop segment that is two times larger than the high-frequency component P b ; (3) the harmonic mode P b shows the largest deviation from a sinusoidal loop shape at the loop apex. We conclude that multiple harmonic modes with different displacement profiles can be excited simultaneously even in closely spaced strands, similar to the overtones of a violin string.

Growth and phase transformations of Ir on Ge(111)

Science.gov (United States)

Mullet, C. H.; Stenger, B. H.; Durand, A. M.; Morad, J. A.; Sato, Y.; Poppenheimer, E. C.; Chiang, S.

2017-12-01

The growth of Ir on Ge(111) as a function of temperature between 23 °C and 820 °C is characterized with low energy electron microscopy (LEEM), low energy electron diffraction (LEED), scanning tunneling microscopy (STM), and x-ray photoemission spectroscopy (XPS). Deposition onto a substrate at 350 °C revealed a novel growth mode consisting of multilayer Ir islands with (√3 × √3)R30° (abbreviated as √3) structure interconnected by ;bridges; of single-layer Ir several atoms wide. For deposition onto substrates above 500 °C, the √3 Ir phase grows with dendritic morphology, and substrate step bunches act as barriers to √3 Ir growth. LEEM images showed Stranski-Krastanov growth for 650-820 °C: after the √3 phase covers the surface, corresponding to 2 monolayers (ML) Ir coverage, multilayer hexagonal-shaped Ir islands form, surrounded by regions of IrGe alloy. Hexagonal-shaped Ir islands also formed upon heating 1.2 ML of √3 Ir beyond 830 °C, which resulted in the elimination of √3 structure from the surface. The transformation from √3 to (1 × 1) structure upon heating to 830 °C was an irreversible surface phase transition. Annealing > 2.0 ML of Ir in the √3 phase above the 830 °C disorder temperature, followed by cooling, produced a (3 × 1) structure. Subsequent heating and cooling through 830 °C give evidence for a reversible (3 × 1) to (1 × 1) phase transition.

Biochemical applications of FT-IR spectroscopy

NARCIS (Netherlands)

Pistorius, A.M.A.

1996-01-01

This thesis describes the use of (FT-)IR spectroscopy in general biochemical research. In chapter 3, IR spectroscopy is used in the quantitation of residual detergent after reconstitution of an integral membrane protein in a pre-defined lipid matrix. This chapter discusses the choice of the

Future development of IR thermovision weather satellite equipment

Science.gov (United States)

Listratov, A. V.

1974-01-01

The self radiation of the surface being viewed is used for image synthesis in IR thermovision equipment. The installation of such equipment aboard weather satellites makes it possible to obtain cloud cover pictures of the earth's surface in a complete orbit, regardless of the illumination conditions, and also provides quantitative information on the underlying surface temperature and cloud top height. Such equipment is used successfully aboard the Soviet satellites of the Meteor system, and experimentally on the American satellites of the Nimbus series. With regard to surface resolution, the present-day IR weather satellite equipment is inferior to the television equipment. This is due primarily to the comparatively low detectivity of the IR detectors used. While IR equipment has several fundamental advantages in comparison with the conventional television equipment, the problem arises of determining the possibility for future development of weather satellite IR thermovision equipment. Criteria are examined for evaluating the quality of IR.

Soft Neutrosophic Loops and Their Generalization

Directory of Open Access Journals (Sweden)

Mumtaz Ali

2014-06-01

Full Text Available Soft set theory is a general mathematical tool for dealing with uncertain, fuzzy, not clearly defined objects. In this paper we introduced soft neutrosophic loop,soft neutosophic biloop, soft neutrosophic N -loop with the discuission of some of their characteristics. We also introduced a new type of soft neutrophic loop, the so called soft strong neutrosophic loop which is of pure neutrosophic character. This notion also found in all the other corresponding notions of soft neutrosophic thoery. We also given some of their properties of this newly born soft structure related to the strong part of neutrosophic theory.

Two- and three-loop amplitudes in covariant loop calculus

International Nuclear Information System (INIS)

Roland, K.

1988-04-01

We study 2- and 3-loop vacuum-amplitudes for the closed bosonic string. We compare two sets of expressions for the corresponding density on moduli space: One, based on the covariant Reggeon loop calculus (where modular invariance is not manifest). The other, based on analytic geometry. We want to prove identity between the two sets of expressions. Quite apart from demonstrating modular invariance of the Reggeon results, this would in itself be a remarkable mathematical feature. Identity is established to 'high' order in some moduli and exactly in others. The expansions reveal an essentially number-theoretical structure. Agreement is found only by exploiting the connection between the 4 Jacobi θ-functions and number theory. (orig.)

Two- and three-loop amplitudes in covariant loop calculus

International Nuclear Information System (INIS)

Roland, K.

1989-01-01

We study two- and three-loop vacuum amplitudes for the closed bosonic string. We compare two sets of expressions for the corresponding density on moduli space. One is based on the covariant reggeon loop calculus (where modular invariance is not manifest). The other is based on analytic geometry. We want to prove identity between the two sets of expressions. Quite apart from demonstrating modular invariance of the reggeon results, this would in itself be a remarkable mathematical feature. Identity is established to ''high'' order in some moduli and exactly in others. The expansions reveal an essentially number-theoretic structure. Agreement is found only by exploiting the connection between the four Jacobi θ-functions and number theory. (orig.)

High-temperature helium-loop facility

International Nuclear Information System (INIS)

Tokarz, R.D.

1981-09-01

The high-temperature helium loop is a facility for materials testing in ultrapure helium gas at high temperatures. The closed loop system is capable of recirculating high-purity helium or helium with controlled impurities. The gas loop maximum operating conditions are as follows: 300 psi pressure, 500 lb/h flow rate, and 2100 0 F temperature. The two test sections can accept samples up to 3.5 in. diameter and 5 ft long. The gas loop is fully instrumented to continuously monitor all parameters of loop operation as well as helium impurities. The loop is fully automated to operate continuously and requires only a daily servicing by a qualified operator to replenish recorder charts and helium makeup gas. Because of its versatility and high degree of parameter control, the helium loop is applicable to many types of materials research. This report describes the test apparatus, operating parameters, peripheral systems, and instrumentation system. The experimental capabilities and test conand presents the results that have been obtained. The study has been conducted using a four-phase approach. The first phase develops the solution to the steady-state radon-diffusion equation in one-dimensieered barriers; disposal charge analysis; analysis of spent fuel policy implementation; spent f water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Uranium concentrations in the sediments which were above detection limits ranged from 0.10 t 51.2 ppM. The mean of the logarithms of the uranium concentrations was 0.53. A group of high uranium concentrations occurs near the junctions of quadrangles AB, AC, BB, a 200 mK. In case 2), x-ray studies of isotopic phase separation in 3 He-- 4 He bcc solids were carried out by B. A. Fraass

Human-in-the-Loop Assessment of Alternative Clearances in Interval Management Arrival Operations

Science.gov (United States)

Baxley, Brian T.; Wilson, Sara R.; Swieringa, Kurt A.; Johnson, William C.; Roper, Roy D.; Hubbs, Clay E.; Goess, Paul A.; Shay, Richard F.

2016-01-01

Interval Management Alternative Clearances (IMAC) was a human-in-the-loop simulation experiment conducted to explore the Air Traffic Management (ATM) Technology Demonstration (ATD-1) Concept of Operations (ConOps), which combines advanced arrival scheduling, controller decision support tools, and aircraft avionics to enable multiple time deconflicted, efficient arrival streams into a high-density terminal airspace. Interval Management (IM) is designed to support the ATD-1 concept by having an "Ownship" (IM-capable) aircraft achieve or maintain a specific time or distance behind a "Target" (preceding) aircraft. The IM software uses IM clearance information and the Ownship data (route of flight, current location, and wind) entered by the flight crew, and the Target aircraft's Automatic Dependent Surveillance-Broadcast state data, to calculate the airspeed necessary for the IM-equipped aircraft to achieve or maintain the assigned spacing goal.

Loop Quantum Gravity

Directory of Open Access Journals (Sweden)

Rovelli Carlo

1998-01-01

Full Text Available The problem of finding the quantum theory of the gravitational field, and thus understanding what is quantum spacetime, is still open. One of the most active of the current approaches is loop quantum gravity. Loop quantum gravity is a mathematically well-defined, non-perturbative and background independent quantization of general relativity, with its conventional matter couplings. Research in loop quantum gravity today forms a vast area, ranging from mathematical foundations to physical applications. Among the most significant results obtained are: (i The computation of the physical spectra of geometrical quantities such as area and volume, which yields quantitative predictions on Planck-scale physics. (ii A derivation of the Bekenstein-Hawking black hole entropy formula. (iii An intriguing physical picture of the microstructure of quantum physical space, characterized by a polymer-like Planck scale discreteness. This discreteness emerges naturally from the quantum theory and provides a mathematically well-defined realization of Wheeler's intuition of a spacetime ``foam''. Long standing open problems within the approach (lack of a scalar product, over-completeness of the loop basis, implementation of reality conditions have been fully solved. The weak part of the approach is the treatment of the dynamics: at present there exist several proposals, which are intensely debated. Here, I provide a general overview of ideas, techniques, results and open problems of this candidate theory of quantum gravity, and a guide to the relevant literature.

Saturation Mutagenesis of the HIV-1 Envelope CD4 Binding Loop Reveals Residues Controlling Distinct Trimer Conformations.

Directory of Open Access Journals (Sweden)

Maria Duenas-Decamp

2016-11-01

Full Text Available The conformation of HIV-1 envelope (Env glycoprotein trimers is key in ensuring protection against waves of neutralizing antibodies generated during infection, while maintaining sufficient exposure of the CD4 binding site (CD4bs for viral entry. The CD4 binding loop on Env is an early contact site for CD4 while penetration of a proximal cavity by CD4 triggers Env conformational changes for entry. The role of residues in the CD4 binding loop in regulating the conformation of the trimer and trimer association domain (TAD was investigated using a novel saturation mutagenesis approach. Single mutations identified, resulted in distinct trimer conformations affecting CD4bs exposure, the glycan shield and the TAD across diverse HIV-1 clades. Importantly, mutations that improve access to the CD4bs without exposing the immunodominant V3 loop were identified. The different trimer conformations identified will affect the specificity and breadth of nabs elicited in vivo and are important to consider in design of Env immunogens for vaccines.

Estimation of complex permittivity using loop antenna

DEFF Research Database (Denmark)

Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

2004-01-01

A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna.......A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna....

ϕ{sup 3} theory with F{sub 4} flavor symmetry in 6−2ϵ dimensions: 3-loop renormalization and conformal bootstrap

Energy Technology Data Exchange (ETDEWEB)

Pang, Yi [Max-Planck-Insitut für Gravitationsphysik (Albert-Einstein-Institut),Am Mühlenberg 1, Potsdam, DE-14476 (Germany); Rong, Junchen [Fields, Gravity & Strings, Center for Theoretical Physics of the Universe,Institute for Basic Sciences, Daejeon, 305-811 (Korea, Republic of); Su, Ning [CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,Chinese Academy of Sciences, Zhong Guan Cun East Street 55 #,P.O. Box 2735, Beijing, 100190 (China)

2016-12-14

We consider ϕ{sup 3} theory in 6−2ϵ with F{sub 4} global symmetry. The beta function is calculated up to 3 loops, and a stable unitary IR fixed point is observed. The anomalous dimensions of operators quadratic or cubic in ϕ are also computed. We then employ conformal bootstrap technique to study the fixed point predicted from the perturbative approach. For each putative scaling dimension of ϕ (Δ{sub ϕ}), we obtain the corresponding upper bound on the scaling dimension of the second lowest scalar primary in the 26 representation (Δ{sub 26}{sup 2nd}) which appears in the OPE of ϕ×ϕ. In D=5.95, we observe a sharp peak on the upper bound curve located at Δ{sub ϕ} equal to the value predicted by the 3-loop computation. In D=5, we observe a weak kink on the upper bound curve at (Δ{sub ϕ},Δ{sub 26}{sup 2nd})=(1.6,4).

IR Cards: Inquiry-Based Introduction to Infrared Spectroscopy

Science.gov (United States)

Bennett, Jacqueline; Forster, Tabetha

2010-01-01

As infrared spectroscopy (IR) is frequently used in undergraduate organic chemistry courses, an inductive introduction to IR spectroscopy that uses index cards printed with spectra, structures, and chemical names is described. Groups of students are given an alphabetized deck of these "IR cards" to sort into functional groups. The students then…

Quantitative gas analysis with FT-IR

DEFF Research Database (Denmark)

Bak, J.; Larsen, A.

1995-01-01

Calibration spectra of CO in the 2.38-5100 ppm concentration range (22 spectra) have been measured with a spectral resolution of 4 cm(-1), in the mid-IR (2186-2001 cm(-1)) region, with a Fourier transform infrared (FT-IR) instrument. The multivariate calibration method partial least-squares (PLS1...

Validity and reproducibility of HOMA-IR, 1/HOMA-IR, QUICKI and McAuley's indices in patients with hypertension and type II diabetes.

Science.gov (United States)

Sarafidis, P A; Lasaridis, A N; Nilsson, P M; Pikilidou, M I; Stafilas, P C; Kanaki, A; Kazakos, K; Yovos, J; Bakris, G L

2007-09-01

The aim of this study was to evaluate the validity and reliability of homeostasis model assessment-insulin resistance (HOMA-IR) index, its reciprocal (1/HOMA-IR), quantitative insulin sensitivity check index (QUICKI) and McAuley's index in hypertensive diabetic patients. In 78 patients with hypertension and type II diabetes glucose, insulin and triglyceride levels were determined after a 12-h fast to calculate these indices, and insulin sensitivity (IS) was measured with the hyperinsulinemic euglycemic clamp technique. Two weeks later, subjects had again their glucose, insulin and triglycerides measured. Simple and multiple linear regression analysis were applied to assess the validity of these indices compared to clamp IS and coefficients of variation between the two visits were estimated to assess their reproducibility. HOMA-IR index was strongly and inversely correlated with the basic IS clamp index, the M-value (r=-0.572, PHOMA-IR and QUICKI indices were positively correlated with the M-value (r=0.342, PHOMA-IR was the best fit of clamp-derived IS. Coefficients of variation between the two visits were 23.5% for HOMA-IR, 19.2% for 1/HOMA-IR, 7.8% for QUICKI and 15.1% for McAuley's index. In conclusion, HOMA-IR, 1/HOMA-IR and QUICKI are valid estimates of clamp-derived IS in patients with hypertension and type II diabetes, whereas the validity of McAuley's index needs further evaluation. QUICKI displayed better reproducibility than the other indices.

Functional Fourier transforms and the loop equation

International Nuclear Information System (INIS)

Bershadskii, M.A.; Vaisburd, I.D.; Migdal, A.A.

1986-01-01

The Migdal-Makeenko momentum-space loop equation is investigated. This equation is derived from the ordinary loop equation by taking the Fourier transform of the Wilson functional. A perturbation theory is constructed for the new equation and it is proved that the action of the loop operator is determined by vertex functions which coincide with those of the previous equation. It is shown how the ghost loop arises in direct iterations of the momentum-space equation with respect to the coupling constant. A simple example is used to illustrate the mechanism of appearance of an integration in the interior loops in transition to observables

IR sensor for monitoring of burner flame; IR sensor foer oevervakning av braennarflamma

Energy Technology Data Exchange (ETDEWEB)

Svanberg, Marcus; Funkquist, Jonas; Clausen, Soennik; Wetterstroem, Jonas

2007-12-15

To obtain a smooth operation of the coal-fired power plants many power plant managers have installed online mass flow measurement of coal to all burners. This signal is used to monitor the coal mass flow to the individual burner and match it with appropriate amount of air and also to monitor the distribution of coal between the burners. The online mass flow measurement system is very expensive (approximately 150 kEUR for ten burners) and is not beneficial for smaller plants. The accuracy of the measurement and the sample frequency are also questionable. The idea in this project has been to evaluate a cheaper system that can present the same information and may also provide better accuracy and faster sample frequency. The infrared sensor is a cheap narrow banded light emission sensor that can be placed in a water cooed probe. The sensor was directed at the burner flame and the emitted light was monitored. Through calibration the mass flow of coal can be presented. Two measurement campaigns were performed. Both campaigns were carried out in Nordjyllandsverket in Denmark even though the second campaign was planned to be in Uppsala. Due to severe problems in the Uppsala plant the campaign was moved to Nordjyllandsverket. The pre-requisites for the test plant were that online measurement of coal flow was installed. In Nordjyllandsverket 4 out of 16 burners have the mass flow measurement installed. Risoe Laboratories has vast experiences in the IR technology and they provided the IR sensing equipment. One IR sensor was placed in the flame guard position just behind the flame directed towards the ignition zone. A second sensor was placed at the boiler wall directed towards the flame. The boiler wall position did not give any results and the location was not used during the second campaign. The flame-guard-positioned-sensor- signal was thoroughly evaluated and the results show that there is a clear correlation between the coal mass flow and the IR sensor signal. Tests were

Towards the use of Structural Loop Analysis to Study System Behaviour of Socio-Ecological Systems.

Science.gov (United States)

Abram, Joseph; Dyke, James

2016-04-01

Maintaining socio-ecological systems in desirable states is key to developing a growing economy, alleviating poverty and achieving a sustainable future. While the driving forces of an environmental system are often well known, the dynamics impacting these drivers can be hidden within a tangled structure of causal chains and feedback loops. A lack of understanding of a system's dynamic structure and its influence on a system's behaviour can cause unforeseen side-effects during model scenario testing and policy implementation. Structural Loop analysis of socio-ecological system models identifies dominant feedback structures during times of behavioural shift, allowing the user to monitor key influential drivers during model simulation. This work carries out Loop Eigenvalue Elasticity Analysis (LEEA) on three system dynamic models, exploring tipping points in lake systems undergoing eutrophication. The purpose is to explore the potential benefits and limitations of the technique in the field of socio-ecology. The LEEA technique shows promise for socio-ecological systems which undergo regime shifts or express oscillatory trends, but shows limited usefulness with large models. The results of this work highlight changes in feedback loop dominance, years prior to eutrophic tipping events in lake systems. LEEA could be used as an early warning signal to impending system changes, complementary to other known early warning signals. This approach could improve our understanding during critical times of a system's behaviour, changing how we approach model analysis and the way scenario testing and policy implementation are addressed in socio-ecological system models.

Loop Evolution Observed with AIA and Hi-C

Science.gov (United States)

Mulu-Moore, Fana; Winebarger, Amy R.; Cirtain, Jonathan W.; Kobayashi, Ken; Korreck, Kelly E.; Golub, Leon; Kuzin, Sergei; Walsh, Robert William; DeForest, Craig E.; De Pontieu, Bart;

IR spectroscopy at the ITO-organic interface

Energy Technology Data Exchange (ETDEWEB)

Alt, Milan [Karlsruher Institut fuer Technologie, Karlsruhe (Germany); Shazada, Ahmad [Max-Planck Institut fuer Polymerforschung, Mainz (Germany); Tamanai, Akemi; Trollmann, Jens; Glaser, Tobias; Beck, Sebastian; Tengeler, Sven; Pucci, Annemarie [Kirchhoff-Institut fuer Physik, Heidelberg (Germany)

2012-07-01

Thin films of P3HT have been prepared by spin coating and electrooxidative polymerization on platinum- and ITO-coated substrates. Additionally, P3HT-films on silicon substrates have been prepared by spin coating only. The measured IR spectra of the spin coated films allowed for an elaboration of a detailed optical model for P3HT, which has been used to simulate IR reflection-absorption spectra on ITO and Pt substrates. Comparison of simulated spectra with measurements revealed no substrate influence on the IR spectra for the spincoated films. In case of spincoated P3HT-films on ITO-substrate, the obtained IR spectra correspond to simulation data very well up to 6000 wavenumbers. In the electropolymerized P3HT films we have identified residuals of the electrolyte ionic liquid, acting as dopand for P3HT. While IR spectra of the electropolymerized P3HT films on Pt substrate could be explained reasonably well as a superposition of chemically doped P3HT and the ionic electrolyte, the IR spectra of electropolymerized P3HT films on ITO substrates showed strongly deposition-time dependent deviations. These were most likely related to varying properties of the ITO surface between reference and sample measurement due to an interaction of ITO and the electrolyte at the film-substrate interface.

Operational experience - Lessons learned from IRS-reports in Germany

International Nuclear Information System (INIS)

Wetzel, N.; Maqua, M.

2005-01-01

The international Incident Reporting System (IRS), jointly operated by IAEA and OECD-NEA, is a main source of safety significant findings and lessons learned of nuclear operating experience. GRS (Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH) is a scientific-technical expert and research organisation. On Behalf of the Federal Minister of Environment, Nature Conservation and Reactor Safety (BMU), GRS provides the IRS officer. The evaluation of IRS-Reports and the dissemination of the main findings including the assessment of the relevance for German NPPs is task of GRS. The value of IRS is among experts undoubted. But nevertheless, the reporting to IRS decreases since some years. This presentation is aimed to show the support of IRS in strengthening the safety of German NPPs. The evaluation of IRS-Reports at GRS is three-fold. It comprises initial screening, quarterly and yearly reporting and the development of specific German Information Notices on safety significant events with direct applicability to German NPPs. Some examples of lessons learned from recent international events are discussed below. These examples shall demonstrate that the use of the IRS enhances significantly the knowledge on operational events. (author)

Optical and IR light curves of VV Puppis

International Nuclear Information System (INIS)

Szkody, P.; Bailey, J.A.; Hough, J.H.

1983-01-01

We present optical (0.36 to 0.6 μm) light curves with time resolutions of seconds and infrared (IR) (1.25 to 2.2 μm) light curves with time resolutions of minutes for VV Puppis during a high state. The optical light curves show a single hump with largest amplitude in the V filter, while the IR light curves show a double hump sinusoidal variation. Flickering is evident in both the optical and IR light curves, with the largest amplitude in optical B light. Through subtraction of the low state fluxes from our high state values, we obtain a flux distribution of the accretion column which peaks at 0.55 μm and becomes #betta# 2 in the IR, consistent with current cyclotron models. Comparison of the observed IR variations throughout the orbit with the expected variations due to an M4 star heated by an accretion column at an inclination of 66 0 suggests that the IR light is a combination of the secondary star plus contributions from two emitting poles. (author)

Evolution of the vertebrate insulin receptor substrate (Irs) gene family.

Science.gov (United States)

Al-Salam, Ahmad; Irwin, David M

2017-06-23

Insulin receptor substrate (Irs) proteins are essential for insulin signaling as they allow downstream effectors to dock with, and be activated by, the insulin receptor. A family of four Irs proteins have been identified in mice, however the gene for one of these, IRS3, has been pseudogenized in humans. While it is known that the Irs gene family originated in vertebrates, it is not known when it originated and which members are most closely related to each other. A better understanding of the evolution of Irs genes and proteins should provide insight into the regulation of metabolism by insulin. Multiple genes for Irs proteins were identified in a wide variety of vertebrate species. Phylogenetic and genomic neighborhood analyses indicate that this gene family originated very early in vertebrae evolution. Most Irs genes were duplicated and retained in fish after the fish-specific genome duplication. Irs genes have been lost of various lineages, including Irs3 in primates and birds and Irs1 in most fish. Irs3 and Irs4 experienced an episode of more rapid protein sequence evolution on the ancestral mammalian lineage. Comparisons of the conservation of the proteins sequences among Irs paralogs show that domains involved in binding to the plasma membrane and insulin receptors are most strongly conserved, while divergence has occurred in sequences involved in interacting with downstream effector proteins. The Irs gene family originated very early in vertebrate evolution, likely through genome duplications, and in parallel with duplications of other components of the insulin signaling pathway, including insulin and the insulin receptor. While the N-terminal sequences of these proteins are conserved among the paralogs, changes in the C-terminal sequences likely allowed changes in biological function.

High pressure experimental water loop

International Nuclear Information System (INIS)

Grenon, M.

1958-01-01

A high pressure experimental water loop has been made for studying the detection and evolution of cladding failure in a pressurized reactor. The loop has been designed for a maximum temperature of 360 deg. C, a maximum of 160 kg/cm 2 and flow rates up to 5 m 3 /h. The entire loop consists of several parts: a main circuit with a canned rotor circulation pump, steam pressurizer, heating tubes, two hydro-cyclones (one de-gasser and one decanter) and one tubular heat exchanger; a continuous purification loop, connected in parallel, comprising pressure reducing valves and resin pots which also allow studies of the stability of resins under pressure, temperature and radiation; following the gas separator is a gas loop for studying the recombination of the radiolytic gases in the steam phase. The preceding circuits, as well as others, return to a low pressure storage circuit. The cold water of the low pressure storage flask is continuously reintroduced into the high pressure main circuit by means of a return pump at a maximum head of 160 kg /cm 2 , and adjusted to the pressurizer level. This loop is also a testing bench for the tight high pressure apparatus. The circulating pump and the connecting flanges (Oak Ridge type) are water-tight. The feed pump and the pressure reducing valves are not; the un-tight ones have a system of leak recovery. To permanently check the tightness the circuit has been fitted with a leak detection system (similar to the HRT one). (author) [fr

Near-IR laser-triggered target cell collection using a carbon nanotube-based cell-cultured substrate.

Science.gov (United States)

Sada, Takao; Fujigaya, Tsuyohiko; Niidome, Yasuro; Nakazawa, Kohji; Nakashima, Naotoshi

2011-06-28

Unique near-IR optical properties of single-walled carbon nanotube (SWNTs) are of interest in many biological applications. Here we describe the selective cell detachment and collection from an SWNT-coated cell-culture dish triggered by near-IR pulse laser irradiation. First, HeLa cells were cultured on an SWNT-coated dish prepared by a spraying of an aqueous SWNT dispersion on a glass dish. The SWNT-coated dish was found to show a good cell adhesion behavior as well as a cellular proliferation rate similar to a conventional glass dish. We discovered, by near-IR pulse laser irradiation (at the laser power over 25 mW) to the cell under optical microscopic observation, a quick single-cell detachment from the SWNT-coated surface. Shockwave generation from the irradiated SWNTs is expected to play an important role for the cell detachment. Moreover, we have succeeded in catapulting the target single cell from the cultured medium when the depth of the medium was below 150 μm and the laser power was stronger than 40 mW. The captured cell maintained its original shape. The retention of the genetic information of the cell was confirmed by the polymerase chain reaction (PCR) technique. A target single-cell collection from a culture medium under optical microscopic observation is significant in wide fields of single-cell studies in biological areas.

Automation of loop amplitudes in numerical approach

International Nuclear Information System (INIS)

Fujimoto, J.; Ishikawa, T.; Shimizu, Y.; Kato, K.; Nakazawa, N.; Kaneko, T.

1997-01-01

An automatic calculating system GRACE-L1 of one-loop Feynman amplitude is reviewed. This system can be applied to 2 to 2-body one-loop processes. A sample calculation of 2 to 3-body one-loop amplitudes is also presented. (orig.)

Loop-quantum-gravity vertex amplitude.

Science.gov (United States)

Engle, Jonathan; Pereira, Roberto; Rovelli, Carlo

2007-10-19

Spin foam models are hoped to provide the dynamics of loop-quantum gravity. However, the most popular of these, the Barrett-Crane model, does not have the good boundary state space and there are indications that it fails to yield good low-energy n-point functions. We present an alternative dynamics that can be derived as a quantization of a Regge discretization of Euclidean general relativity, where second class constraints are imposed weakly. Its state space matches the SO(3) loop gravity one and it yields an SO(4)-covariant vertex amplitude for Euclidean loop gravity.

THE CORONAL LOOP INVENTORY PROJECT: EXPANDED ANALYSIS AND RESULTS

Energy Technology Data Exchange (ETDEWEB)

Schmelz, J. T. [USRA, 7178 Columbia Gateway Drive, Columbia, MD 21046 (United States); Christian, G. M.; Chastain, R. A., E-mail: jschmelz@usra.edu [Physics Department, University of Memphis, Memphis, TN 38152 (United States)

2016-11-10

We have expanded upon earlier work that investigates the relative importance of coronal loops with isothermal versus multithermal cross-field temperature distributions. These results are important for determining if loops have substructure in the form of unresolved magnetic strands. We have increased the number of loops targeted for temperature analysis from 19 to 207 with the addition of 188 new loops from multiple regions. We selected all loop segments visible in the 171 Å images of the Atmospheric Imaging Assembly (AIA) that had a clean background. Eighty-six of the new loops were rejected because they could not be reliably separated from the background in other AIA filters. Sixty-one loops required multithermal models to reproduce the observations. Twenty-eight loops were effectively isothermal, that is, the plasma emission to which AIA is sensitive could not be distinguished from isothermal emission, within uncertainties. Ten loops were isothermal. Also, part of our inventory was one small flaring loop, one very cool loop whose temperature distribution could not be constrained by the AIA data, and one loop with inconclusive results. Our survey can confirm an unexpected result from the pilot study: we found no isothermal loop segments where we could properly use the 171-to-193 ratio method, which would be similar to the analysis done for many loops observed with TRACE and EIT. We recommend caution to observers who assume the loop plasma is isothermal, and hope that these results will influence the direction of coronal heating models and the effort modelers spend on various heating scenarios.

Bootstrapping the Three-Loop Hexagon

Energy Technology Data Exchange (ETDEWEB)

Dixon, Lance J.; /CERN /SLAC; Drummond, James M.; /CERN /Annecy, LAPTH; Henn, Johannes M.; /Humboldt U., Berlin /Santa Barbara, KITP

2011-11-08

We consider the hexagonal Wilson loop dual to the six-point MHV amplitude in planar N = 4 super Yang-Mills theory. We apply constraints from the operator product expansion in the near-collinear limit to the symbol of the remainder function at three loops. Using these constraints, and assuming a natural ansatz for the symbol's entries, we determine the symbol up to just two undetermined constants. In the multi-Regge limit, both constants drop out from the symbol, enabling us to make a non-trivial confirmation of the BFKL prediction for the leading-log approximation. This result provides a strong consistency check of both our ansatz for the symbol and the duality between Wilson loops and MHV amplitudes. Furthermore, we predict the form of the full three-loop remainder function in the multi-Regge limit, beyond the leading-log approximation, up to a few constants representing terms not detected by the symbol. Our results confirm an all-loop prediction for the real part of the remainder function in multi-Regge 3 {yields} 3 scattering. In the multi-Regge limit, our result for the remainder function can be expressed entirely in terms of classical polylogarithms. For generic six-point kinematics other functions are required.

Lattice QED in the loop space

International Nuclear Information System (INIS)

Fort, H.

1994-01-01

We present a survey on the state of the art in the formulation of lattice compact QED in the space of loops. In a first part we review our most recent Hamiltonian results which signal a second order transition for (3+1) compact QED. We devote the second part to the Lagrangian loop formalism, showing the equivalence of the recently proposed loop action with the Villain form. (orig.)

Loop quantization as a continuum limit

International Nuclear Information System (INIS)

Manrique, Elisa; Oeckl, Robert; Weber, Axel; Zapata, Jose A

2006-01-01

We present an implementation of Wilson's renormalization group and a continuum limit tailored for loop quantization. The dynamics of loop-quantized theories is constructed as a continuum limit of the dynamics of effective theories. After presenting the general formalism we show as a first explicit example the 2D Ising field theory, an interacting relativistic quantum field theory with local degrees of freedom quantized by loop quantization techniques

Dynamic control of modeled tonic-clonic seizure states with closed-loop stimulation

Directory of Open Access Journals (Sweden)

Bryce eBeverlin II

2013-02-01

Full Text Available Seizure control using deep brain stimulation (DBS provides an alternative therapy to patients with intractable and drug resistant epilepsy. This paper presents novel DBS stimulus protocols to disrupt seizures. Two protocols are presented: open-loop stimulation and a closed-loop feedback system utilizing measured firing rates to adjust stimulus frequency. Stimulation suppression is demonstrated in a computational model using 3000 excitatory Morris-Lecar model neurons connected with depressing synapses. Cells are connected using second order network topology to simulate network topologies measured in cortical networks. The network spontaneously switches from tonic to clonic as synaptic strengths and tonic input to the neurons decreases. To this model we add periodic stimulation pulses to simulate DBS. Periodic forcing can synchronize or desynchronize an oscillating population of neurons, depending on the stimulus frequency and amplitude. Therefore, it is possible to either extend or truncate the tonic or clonic phases of the seizure. Stimuli applied at the firing rate of the neuron generally synchronize the population while stimuli slightly slower than the firing rate prevent synchronization. We present an adaptive stimulation algorithm that measures the firing rate of a neuron and adjusts the stimulus to maintain a relative stimulus frequency to firing frequency and demonstrate it in a computational model of a tonic-clonic seizure. This adaptive algorithm can affect the duration of the tonic phase using much smaller stimulus amplitudes than the open-loop control.

Flat Knitting Loop Deformation Simulation Based on Interlacing Point Model

Directory of Open Access Journals (Sweden)

Jiang Gaoming

2017-12-01

Full Text Available In order to create realistic loop primitives suitable for the faster CAD of the flat-knitted fabric, we have performed research on the model of the loop as well as the variation of the loop surface. This paper proposes an interlacing point-based model for the loop center curve, and uses the cubic Bezier curve to fit the central curve of the regular loop, elongated loop, transfer loop, and irregular deformed loop. In this way, a general model for the central curve of the deformed loop is obtained. The obtained model is then utilized to perform texture mapping, texture interpolation, and brightness processing, simulating a clearly structured and lifelike deformed loop. The computer program LOOP is developed by using the algorithm. The deformed loop is simulated with different yarns, and the deformed loop is applied to design of a cable stitch, demonstrating feasibility of the proposed algorithm. This paper provides a loop primitive simulation method characterized by lifelikeness, yarn material variability, and deformation flexibility, and facilitates the loop-based fast computer-aided design (CAD of the knitted fabric.

Variational solution of the loop equation in QCD

International Nuclear Information System (INIS)

Agishtein, M.E.; Migdal, A.A.

1988-01-01

A new technique for the large N loop equation of QCD is worked out. The Wilson loop W(C) is approximated by a Gaussian functional. The parameters are fitted to the loop equation, after which the equation is statisfied up to 0.2%. The resulting Wilson loop corresponds to linearly rising Regge trajectories. The problem of tachyon is still present, but it could be cured by iteration of the loop equation starting from this variational solution. (orig.)

Variational solution of the loop equation in QCD

International Nuclear Information System (INIS)

Agishtein, M.E.; Migdal, A.A.

1988-01-01

A new technique for the large N loop equation of QCD is worked out. The Wilson loop W(C) is approximated by a Gaussian functional. The parameters are fitted to the loop equation, after which the equation is satisfied up to 0.2%. The resulting Wilson loop corresponds to linearly rising Regge trajectories. The problem of tachyon is still present, but it could be cured by iteration of the loop equation starting from this variational solution

Loop Quantum Cosmology

Directory of Open Access Journals (Sweden)

Bojowald Martin

2008-07-01

Full Text Available Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a classical spacetime inevitably comes to an end after a finite amount of proper time. This presents a breakdown of the classical picture and requires an extended theory for a meaningful description. Since small length scales and high curvatures are involved, quantum effects must play a role. Not only the singularity itself but also the surrounding spacetime is then modified. One particular theory is loop quantum cosmology, an application of loop quantum gravity to homogeneous systems, which removes classical singularities. Its implications can be studied at different levels. The main effects are introduced into effective classical equations, which allow one to avoid the interpretational problems of quantum theory. They give rise to new kinds of early-universe phenomenology with applications to inflation and cyclic models. To resolve classical singularities and to understand the structure of geometry around them, the quantum description is necessary. Classical evolution is then replaced by a difference equation for a wave function, which allows an extension of quantum spacetime beyond classical singularities. One main question is how these homogeneous scenarios are related to full loop quantum gravity, which can be dealt with at the level of distributional symmetric states. Finally, the new structure of spacetime arising in loop quantum gravity and its application to cosmology sheds light on more general issues, such as the nature of time.

Loop Quantum Cosmology

Directory of Open Access Journals (Sweden)

Bojowald Martin

2005-12-01

Full Text Available Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a classical space-time inevitably comes to an end after a finite amount of proper time. This presents a breakdown of the classical picture and requires an extended theory for a meaningful description. Since small length scales and high curvatures are involved, quantum effects must play a role. Not only the singularity itself but also the surrounding space-time is then modified. One particular realization is loop quantum cosmology, an application of loop quantum gravity to homogeneous systems, which removes classical singularities. Its implications can be studied at different levels. Main effects are introduced into effective classical equations which allow to avoid interpretational problems of quantum theory. They give rise to new kinds of early universe phenomenology with applications to inflation and cyclic models. To resolve classical singularities and to understand the structure of geometry around them, the quantum description is necessary. Classical evolution is then replaced by a difference equation for a wave function which allows to extend space-time beyond classical singularities. One main question is how these homogeneous scenarios are related to full loop quantum gravity, which can be dealt with at the level of distributional symmetric states. Finally, the new structure of space-time arising in loop quantum gravity and its application to cosmology sheds new light on more general issues such as time.

CHY loop integrands from holomorphic forms

Energy Technology Data Exchange (ETDEWEB)

Gomez, Humberto [Facultad de Ciencias Basicas, Universidad Santiago de Cali,Calle 5 62-00 Barrio Pampalinda, Cali, Valle (Colombia); Perimeter Institute for Theoretical Physics,31 Caroline Street N, Waterloo, ON N2L 2Y5 (Canada); Mizera, Sebastian; Zhang, Guojun [Perimeter Institute for Theoretical Physics,31 Caroline Street N, Waterloo, ON N2L 2Y5 (Canada); Department of Physics & Astronomy, University of Waterloo,Waterloo, ON N2L 3G1 (Canada)

2017-03-16

Recently, the Cachazo-He-Yuan (CHY) approach for calculating scattering amplitudes has been extended beyond tree level. In this paper, we introduce a way of constructing CHY integrands for Φ{sup 3} theory up to two loops from holomorphic forms on Riemann surfaces. We give simple rules for translating Feynman diagrams into the corresponding CHY integrands. As a complementary result, we extend the L-algorithm, originally introduced in https://arxiv.org/abs/1604.05373, to two loops. Using this approach, we are able to analytically verify our prescription for the CHY integrands up to seven external particles at two loops. In addition, it gives a natural way of extending to higher-loop orders.

Differential cellular responses to prolonged LDR-IR in MLH1-proficient and MLH1-deficient colorectal cancer HCT116 cells.

Science.gov (United States)

Yan, Tao; Seo, Yuji; Kinsella, Timothy J

2009-11-15

MLH1 is a key DNA mismatch repair (MMR) protein involved in maintaining genomic stability by participating in the repair of endogenous and exogenous mispairs in the daughter strands during S phase. Exogenous mispairs can result following treatment with several classes of chemotherapeutic drugs, as well as with ionizing radiation. In this study, we investigated the role of the MLH1 protein in determining the cellular and molecular responses to prolonged low-dose rate ionizing radiation (LDR-IR), which is similar to the clinical use of cancer brachytherapy. An isogenic pair of MMR(+) (MLH1(+)) and MMR(-) (MLH1(-)) human colorectal cancer HCT116 cells was exposed to prolonged LDR-IR (1.3-17 cGy/h x 24-96 h). The clonogenic survival and gene mutation rates were examined. Cell cycle distribution was analyzed with flow cytometry. Changes in selected DNA damage repair proteins, DNA damage response proteins, and cell death marker proteins were examined with Western blotting. MLH1(+) HCT116 cells showed greater radiosensitivity with enhanced expression of apoptotic and autophagic markers, a reduced HPRT gene mutation rate, and more pronounced cell cycle alterations (increased late-S population and a G(2)/M arrest) following LDR-IR compared with MLH1(-) HCT116 cells. Importantly, a progressive increase in MLH1 protein levels was found in MLH1(+) cells during prolonged LDR-IR, which was temporally correlated with a progressive decrease in Rad51 protein (involved in homologous recombination) levels. MLH1 status significantly affects cellular responses to prolonged LDR-IR. MLH1 may enhance cell radiosensitivity to prolonged LDR-IR through inhibition of homologous recombination (through inhibition of Rad51).

The base pairing RNA Spot 42 participates in a multi-output feedforward loop to help enact catabolite repression in Escherichia coli

Science.gov (United States)

Beisel, Chase L.; Storz, Gisela

2011-01-01

SUMMARY Bacteria selectively consume some carbon sources over others through a regulatory mechanism termed catabolite repression. Here, we show that the base pairing RNA Spot 42 plays a broad role in catabolite repression in Escherichia coli by directly repressing genes involved in central and secondary metabolism, redox balancing, and the consumption of diverse non-preferred carbon sources. Many of the genes repressed by Spot 42 are transcriptionally activated by the global regulator CRP. Since CRP represses Spot 42, these regulators participate in a specific regulatory circuit called a multi-output feedforward loop. We found that this loop can reduce leaky expression of target genes in the presence of glucose and can maintain repression of target genes under changing nutrient conditions. Our results suggest that base pairing RNAs in feedforward loops can help shape the steady-state levels and dynamics of gene expression. PMID:21292161

The Brain–Intestinal Mucosa–Appendix– Microbiome–Brain Loop

Directory of Open Access Journals (Sweden)

Luis Vitetta

2018-04-01

Full Text Available The brain and the gut are connected from early fetal life. The mother’s exposure to microbial molecules is thought to exert in utero developmental effects on the fetus. These effects could importantly underpin the groundwork for subsequent pathophysiological mechanisms for achieving immunological tolerance and metabolic equilibrium post birth, events that continue through to 3–4 years of age. Furthermore, it is understood that the microbiome promotes cues that instruct the neonate’s mucosal tissues and skin in the language of molecular and cellular biology. Post birth mucosal lymphoid tissue formation and maturation (most probably including the vermiform appendix is microbiota-encouraged co-establishing the intestinal microbiome with a developing immune system. Intestinal mucosal tissue maturation loops the brain-gut-brain and is postulated to influence mood dispositions via shifts in the intestinal microbiome phyla. A plausible appreciation is that dysregulated pro-inflammatory signals from intestinal resident macrophages could breach the loop by providing adverse mood signals via vagus nerve afferents to the brain. In this commentary, we further suggest that the intestinal resident macrophages act as an upstream traffic controller of translocated microbes and metabolites in order to maintain local neuro-endocrine-immunological equilibrium. When macrophages are overwhelmed through intestinal microbiome and intestinal epithelial cell dysbiosis, pro-inflammatory signals are sustained, which may then lead to mood disorders. The administration of probiotics as an adjunctive medicine co-administered with antidepressant medications in improving depressed mood may have biological and clinical standing.

Loop quantum cosmology and singularities.

Science.gov (United States)

Struyve, Ward

2017-08-15

Loop quantum gravity is believed to eliminate singularities such as the big bang and big crunch singularity. This belief is based on studies of so-called loop quantum cosmology which concerns symmetry-reduced models of quantum gravity. In this paper, the problem of singularities is analysed in the context of the Bohmian formulation of loop quantum cosmology. In this formulation there is an actual metric in addition to the wave function, which evolves stochastically (rather than deterministically as the case of the particle evolution in non-relativistic Bohmian mechanics). Thus a singularity occurs whenever this actual metric is singular. It is shown that in the loop quantum cosmology for a homogeneous and isotropic Friedmann-Lemaître-Robertson-Walker space-time with arbitrary constant spatial curvature and cosmological constant, coupled to a massless homogeneous scalar field, a big bang or big crunch singularity is never obtained. This should be contrasted with the fact that in the Bohmian formulation of the Wheeler-DeWitt theory singularities may exist.

Climate Prediction Center IR 4km Dataset

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — CPC IR 4km dataset was created from all available individual geostationary satellite data which have been merged to form nearly seamless global (60N-60S) IR...

Constructing QCD one-loop amplitudes

International Nuclear Information System (INIS)

Forde, D

2008-01-01

In the context of constructing one-loop amplitudes using a unitarity bootstrap approach we discuss a general systematic procedure for obtaining the coefficients of the scalar bubble and triangle integral functions of one-loop amplitudes. Coefficients are extracted after examining the behavior of the cut integrand as the unconstrained parameters of a specifically chosen parameterization of the cut loop momentum approach infinity. Measurements of new physics at the forthcoming experimental program at CERN's Large Hadron Collider (LHC) will require a precise understanding of processes at next-to-leading order (NLO). This places increased demands for the computation of new one-loop amplitudes. This in turn has spurred recent developments towards improved calculational techniques. Direct calculations using Feynman diagrams are in general inefficient. Developments of more efficient techniques have usually centered around unitarity techniques [1], where tree amplitudes are effectively 'glued' together to form loops. The most straightforward application of this method, in which the cut loop momentum is in D = 4, allows for the computation of 'cut-constructible' terms only, i.e. (poly)logarithmic containing terms and any related constants. QCD amplitudes contain, in addition to such terms, rational pieces which cannot be derived using such cuts. These 'missing' rational parts can be extracted using cut loop momenta in D = 4-2 (var e psilon). The greater difficulty of such calculations has restricted the application of this approach, although recent developments [3, 4] have provided new promise for this technique. Recently the application of on-shell recursion relations [5] to obtaining the 'missing' rational parts of one-loop processes [6] has provided an alternative very promising solution to this problem. In combination with unitarity methods an 'on-shell bootstrap' approach provides an efficient technique for computing complete one-loop QCD amplitudes [7]. Additionally

Spin-glass-like behaviour in IrSr2RECu2O8 (RE=Sm and Eu)

International Nuclear Information System (INIS)

Santos-Garcia, A.J. dos; Duijn, J. van; Alario-Franco, M.A.

2008-01-01

We report the results of magnetic and specific heat measurements on the 1212-type compounds IrSr 2 RECu 2 O 8 with RE=Sm and Eu, prepared by high-pressure and high-temperature synthesis. The magnetic susceptibility of these compounds shows a large difference in the temperature dependence of the magnetization measured under zero-field-cooled and field-cooled conditions below 87 and 71 K, respectively, and upon further cooling below ∼10 K substantial maxima are observed too. Further AC susceptibility measurements support a glassy behaviour in lower magnetic transitions whereas the specific heat measurements do not show the typical long-range ordering commonly displayed in ferro, ferri or antiferromagnetic transitions. Hysteresis loops suggest the presence of magnetic clusters in the otherwise paramagnetic zone, indicating that these compounds probably display a reentrant spin-glass transition. Results are presented and discussed. - Graphical abstract: IrSr 2 RECu 2 O 8 with RE=Sm and Eu were prepared by high-pressure and high-temperature synthesis. Both samples adopt a M-1212-type perovskite structure and a microdomain texturing of the long c-axis is observed by TEM. A very interesting magnetic behaviour is observed in these materials. A 'cluster by cluster freezing' model is proposed, instead of the classical individual spin freezing one to explain the spin-glass-like behaviour that seems to coexist with weak ferromagnetism in both compounds

Loop-Loop Interactions Regulate KaiA-Stimulated KaiC Phosphorylation in the Cyanobacterial KaiABC Circadian Clock

Energy Technology Data Exchange (ETDEWEB)

Egli, Martin [Vanderbilt Univ., Nashville, TN (United States); Pattanayek, Rekha [Vanderbilt Univ., Nashville, TN (United States); Sheehan, Jonathan H. [Vanderbilt Univ., Nashville, TN (United States); Xu, Yao [Vanderbilt Univ., Nashville, TN (United States); Mori, Tetsuya [Vanderbilt Univ., Nashville, TN (United States); Smith, Jarrod A. [Vanderbilt Univ., Nashville, TN (United States); Johnson, Carl H. [Vanderbilt Univ., Nashville, TN (United States)

2013-01-25

We found that the Synechococcus elongatus KaiA, KaiB, and KaiC proteins in the presence of ATP generate a post-translational oscillator that runs in a temperature-compensated manner with a period of 24 h. KaiA dimer stimulates phosphorylation of KaiC hexamer at two sites per subunit, T432 and S431, and KaiB dimers antagonize KaiA action and induce KaiC subunit exchange. Neither the mechanism of KaiA-stimulated KaiC phosphorylation nor that of KaiB-mediated KaiC dephosphorylation is understood in detail at present. We demonstrate here that the A422V KaiC mutant sheds light on the former mechanism. It was previously reported that A422V is less sensitive to dark pulse-induced phase resetting and has a reduced amplitude of the KaiC phosphorylation rhythm in vivo. A422 maps to a loop (422-loop) that continues toward the phosphorylation sites. By pulling on the C-terminal peptide of KaiC (A-loop), KaiA removes restraints from the adjacent 422-loop whose increased flexibility indirectly promotes kinase activity. We found in the crystal structure that A422V KaiC lacks phosphorylation at S431 and exhibits a subtle, local conformational change relative to wild-type KaiC. Molecular dynamics simulations indicate higher mobility of the 422-loop in the absence of the A-loop and mobility differences in other areas associated with phosphorylation activity between wild-type and mutant KaiCs. Finally, the A-loop–422-loop relay that informs KaiC phosphorylation sites of KaiA dimer binding propagates to loops from neighboring KaiC subunits, thus providing support for a concerted allosteric mechanism of phosphorylation.

Two-phase Heating in Flaring Loops

Science.gov (United States)

Zhu, Chunming; Qiu, Jiong; Longcope, Dana W.

2018-03-01

We analyze and model a C5.7 two-ribbon solar flare observed by the Solar Dynamics Observatory, Hinode, and GOES on 2011 December 26. The flare is made of many loops formed and heated successively over one and half hours, and their footpoints are brightened in the UV 1600 Å before enhanced soft X-ray and EUV missions are observed in flare loops. Assuming that anchored at each brightened UV pixel is a half flaring loop, we identify more than 6700 half flaring loops, and infer the heating rate of each loop from the UV light curve at the footpoint. In each half loop, the heating rate consists of two phases: intense impulsive heating followed by a low-rate heating that is persistent for more than 20 minutes. Using these heating rates, we simulate the evolution of their coronal temperatures and densities with the model of the “enthalpy-based thermal evolution of loops.” In the model, suppression of thermal conduction is also considered. This model successfully reproduces total soft X-ray and EUV light curves observed in 15 passbands by four instruments GOES, AIA, XRT, and EVE. In this flare, a total energy of 4.9 × 1030 erg is required to heat the corona, around 40% of this energy is in the slow-heating phase. About two-fifths of the total energy used to heat the corona is radiated by the coronal plasmas, and the other three fifth transported to the lower atmosphere by thermal conduction.

Structural Variation and Uniformity among Tetraloop-Receptor Interactions and Other Loop-Helix Interactions in RNA Crystal Structures

Science.gov (United States)

Wu, Li; Chai, Dinggeng; Fraser, Marie E.; Zimmerly, Steven

2012-01-01

Tetraloop-receptor interactions are prevalent structural units in RNAs, and include the GAAA/11-nt and GNRA-minor groove interactions. In this study, we have compiled a set of 78 nonredundant loop-helix interactions from X-ray crystal structures, and examined them for the extent of their sequence and structural variation. Of the 78 interactions in the set, only four were classical GAAA/11-nt motifs, while over half (48) were GNRA-minor groove interactions. The GNRA-minor groove interactions were not a homogeneous set, but were divided into five subclasses. The most predominant subclass is characterized by two triple base pair interactions in the minor groove, flanked by two ribose zipper contacts. This geometry may be considered the “standard” GNRA-minor groove interaction, while the other four subclasses are alternative ways to form interfaces between a minor groove and tetraloop. The remaining 26 structures in the set of 78 have loops interacting with mostly idiosyncratic receptors. Among the entire set, a number of sequence-structure correlations can be identified, which may be used as initial hypotheses in predicting three-dimensional structures from primary sequences. Conversely, other sequence patterns are not predictive; for example, GAAA loop sequences and GG/CC receptors bind to each other with three distinct geometries. Finally, we observe an example of structural evolution in group II introns, in which loop-receptor motifs are substituted for each other while maintaining the larger three-dimensional geometry. Overall, the study gives a more complete view of RNA loop-helix interactions that exist in nature. PMID:23152878

Control-structure interaction in precision pointing servo loops

Science.gov (United States)

Spanos, John T.

1989-01-01

The control-structure interaction problem is addressed via stability analysis of a generic linear servo loop model. With the plant described by the rigid body mode and a single elastic mode, structural flexibility is categorized into one of three types: (1) appendage, (2) in-the-loop minimum phase, and (3) in-the-loop nonminimum phase. Closing the loop with proportional-derivative (PD) control action and introducing sensor roll-off dynamics in the feedback path, stability conditions are obtained. Trade studies are conducted with modal frequency, modal participation, modal damping, loop bandwidth, and sensor bandwidth treated as free parameters. Results indicate that appendage modes are most likely to produce instability if they are near the sensor rolloff, whereas in-the-loop modes are most dangerous near the loop bandwidth. The main goal of this paper is to provide a fundamental understanding of the control-structure interaction problem so that it may benefit the design of complex spacecraft and pointing system servo loops. In this framework, the JPL Pathfinder gimbal pointer is considered as an example.

Numerical evaluation of one-loop QCD amplitudes

DEFF Research Database (Denmark)

Badger, Simon David; Biedermann, Benedikt; Uwer, Peter

2012-01-01

We present the publicly available program NGluon allowing the numerical evaluation of primitive amplitudes at one-loop order in massless QCD. The program allows the computation of one-loop amplitudes for an arbitrary number of gluons. The focus of the present article is the extension to one-loop ...

The relationship between visfatin and HOMA-IR in hypertensive patients, and the effect of antihypertensive drugs on visfatin and HOMA-IR in hypertensive patients with insulin resistance.

Science.gov (United States)

Lan, Jianjun; Chen, Xiaoni; Chen, Xiaoping; Wang, Si; Zhang, Xin; Wu, Kai; He, Sen; Peng, Yong; Jiang, Lingyun; Li, Longxin; Wan, Liyan

2011-10-01

To investigate the correlation between serum visfatin and insulin resistance (IR) in non-diabetic essential hypertensive (EH) patients with and without IR, and to evaluate the effect of antihypertensive treatment on serum visfatin and IR in these patients. A total of 81 non-diabetic EH patients, including 54 with IR and 27 without IR, were enrolled. After two weeks wash-out, patients with IR were randomly assigned to telmisartan (group T) or amlodipine (group A) for 6 months. Blood samples were taken before and after treatment for measurement of routine biochemical parameters, visfatin and insulin resistance (measured by HOMA-IR). Visfatin was independently correlated with HOMA-IR (r=0.845, P=0.000). After 6 months of treatment, both drugs lowered HOMA-IR, more significantly so in group T than group A (P=0.010). Serum visfatin levels increased in group T but decreased in group A. Serum visfatin levels were higher in non-diabetic EH patients with IR compared with those without IR. Visfatin is independently correlated with HOMA-IR. Telmisartan lowers HOMA-IR to a greater extent than amlodipine. Interestingly, serum visfatin increased with telmisartan yet decreased with amlodipine treatment. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A novel IrNi@PdIr/C core-shell electrocatalyst with enhanced activity and durability for the hydrogen oxidation reaction in alkaline anion exchange membrane fuel cells.

Science.gov (United States)

Qin, Bowen; Yu, Hongmei; Jia, Jia; Jun, Chi; Gao, Xueqiang; Yao, Dewei; Sun, Xinye; Song, Wei; Yi, Baolian; Shao, Zhigang

2018-03-08

Herein, a novel non-platinum core-shell catalyst, namely, IrNi@PdIr/C was prepared via a galvanic replacement reaction; it exhibits enhanced hydrogen oxidation activity and excellent stability under alkaline conditions. Electrochemical experiments demonstrated that the mass and specific activities at 50 mV of IrNi@PdIr/C are 2.1 and 2.2 times that of commercial Pt/C in 0.1 M KOH at 298 K, respectively. Moreover, accelerated degradation tests have shown that the electrochemically active surface area (ECSA) of IrNi@PdIr/C reduces by only 5.1%, which is almost 4 times less than that of commercial Pt/C and the mass activity at 50 mV of IrNi@PdIr/C after 2000 potential cycles is still 1.8 times higher than that of aged Pt/C. XRD and XPS analysis suggest that the enhanced HOR activity is attributed to the weakening of the hydrogen binding to the PdIr overlayers induced by the IrNi core. The better stability to potential cycling can be associated with the PdIr shell, which inhibits oxide formation. These results suggest that IrNi@PdIr/C is a promising non-platinum anode catalyst for alkaline anion exchange membrane fuel cells.

Vertically Polarized Omnidirectional Printed Slot Loop Antenna

DEFF Research Database (Denmark)

Kammersgaard, Nikolaj Peter Iversen; Kvist, Søren H.; Thaysen, Jesper

2015-01-01

A novel vertically polarized omnidirectional printed slot loop antenna has been designed, simulated, fabricated and measured. The slot loop works as a magnetic loop. The loop is loaded with inductors to insure uniform and in-phase fields in the slot in order to obtain an omnidirectional radiation...... pattern. The antenna is designed for the 2.45 GHz Industrial, Scientific and Medical band. Applications of the antenna are many. One is for on-body applications since it is ideal for launching a creeping waves due to the polarization....

Towards a closed-loop cochlear implant system: application of embedded monitoring of peripheral and central neural activity.

Science.gov (United States)

Mc Laughlin, Myles; Lu, Thomas; Dimitrijevic, Andrew; Zeng, Fan-Gang

2012-07-01

Although the cochlear implant (CI) is widely considered the most successful neural prosthesis, it is essentially an open-loop system that requires extensive initial fitting and frequent tuning to maintain a high, but not necessarily optimal, level of performance. Two developments in neuroscience and neuroengineering now make it feasible to design a closed-loop CI. One development is the recording and interpretation of evoked potentials (EPs) from the peripheral to the central nervous system. The other is the embedded hardware and software of a modern CI that allows recording of EPs. We review EPs that are pertinent to behavioral functions from simple signal detection and loudness growth to speech discrimination and recognition. We also describe signal processing algorithms used for electric artifact reduction and cancellation, critical to the recording of electric EPs. We then present a conceptual design for a closed-loop CI that utilizes in an innovative way the embedded implant receiver and stimulators to record short latency compound action potentials ( ~1 ms), auditory brainstem responses (1-10 ms) and mid-to-late cortical potentials (20-300 ms). We compare EPs recorded using the CI to EPs obtained using standard scalp electrodes recording techniques. Future applications and capabilities are discussed in terms of the development of a new generation of closed-loop CIs and other neural prostheses.

Whole-loop mitochondrial DNA D-loop sequence variability in Egyptian Arabian equine matrilines

Science.gov (United States)

Hudson, William

2017-01-01

Background Egyptian Arabian horses have been maintained in a state of genetic isolation for over a hundred years. There is only limited genetic proof that the studbook records of female lines of Egyptian Arabian pedigrees are reliable. This study characterized the mitochondrial DNA (mtDNA) signatures of 126 horses representing 14 matrilines in the Egyptian Agricultural Organization (EAO) horse-breeding program. Findings Analysis of the whole D-loop sequence yielded additional information compared to hypervariable region-1 (HVR1) analysis alone, with 42 polymorphic sites representing ten haplotypes compared to 16 polymorphic sites representing nine haplotypes, respectively. Most EAO haplotypes belonged to ancient haplogroups, suggesting origin from a wide geographical area over many thousands of years, although one haplotype was novel. Conclusions Historical families share haplotypes and some individuals from different strains belonged to the same haplogroup: the classical EAO strain designation is not equivalent to modern monophyletic matrilineal groups. Phylogenetic inference showed that the foundation mares of the historical haplotypes were highly likely to have the same haplotypes as the animals studied (p > 0.998 in all cases), confirming the reliability of EAO studbook records and providing the opportunity for breeders to confirm the ancestry of their horses. PMID:28859174

Crystal growth and characterization of Ir-Te compounds

Energy Technology Data Exchange (ETDEWEB)

Kurzhals, Philipp; Weber, Frank; Zocco, Diego; Adelmann, Peter; Merz, Michael; Wolf, Thomas; Kuntz, Sebastian; Grube, Kai [Karlsruhe Institute of Technology, Institute for Solid State Physics, Karlsruhe (Germany)

2016-07-01

IrTe{sub 2} is distinguished by a structural phase transition whose origin is not understood up to the present day. We grew crystals using the self-flux method starting from the reagents iridium and tellurium and got specimen with varying amounts of IrTe{sub 2} and Ir{sub 3}Te{sub 8}, analyzed by x-ray powder diffraction. We studied the transition near T = 280 K in magnetization measurements down to T = 1.8 K probing also for superconductivity, which was reported for intercalated samples. Results indicate that the structural transition happens over an extended range in temperature and superconductivity is absent in our samples. Ir{sub 3}Te{sub 8} is not studied to such an extent as IrTe{sub 2}. In previous publications a structural phase transition is reported. We characterized the transition by performing magnetization measurements and X-ray diffraction.

String breaking with Wilson loops?

CERN Document Server

Kratochvila, S; Kratochvila, Slavo; Forcrand, Philippe de

2003-01-01

A convincing, uncontroversial observation of string breaking, when the static potential is extracted from Wilson loops only, is still missing. This failure can be understood if the overlap of the Wilson loop with the broken string is exponentially small. In that case, the broken string ground state will only be seen if the Wilson loop is long enough. Our preliminary results show string breaking in the context of the 3d SU(2) adjoint static potential, using the L\\"uscher-Weisz exponential variance reduction approach. As a by-product, we measure the fundamental SU(2) static potential with improved accuracy and see clear deviations from Casimir scaling.

BMN correlators by loop equations

International Nuclear Information System (INIS)

Eynard, Bertrand; Kristjansen, Charlotte

2002-01-01

In the BMN approach to N=4 SYM a large class of correlators of interest are expressible in terms of expectation values of traces of words in a zero-dimensional gaussian complex matrix model. We develop a loop-equation based, analytic strategy for evaluating such expectation values to any order in the genus expansion. We reproduce the expectation values which were needed for the calculation of the one-loop, genus one correction to the anomalous dimension of BMN-operators and which were earlier obtained by combinatorial means. Furthermore, we present the expectation values needed for the calculation of the one-loop, genus two correction. (author)

Structural, mechanical, and electronic properties of TaB2, TaB, IrB2, and IrB: First-principle calculations

International Nuclear Information System (INIS)

Zhao Wenjie; Wang Yuanxu

2009-01-01

First-principle calculations were performed to investigate the structural, elastic, and electronic properties of TaB 2 , TaB, IrB 2 , and IrB. The calculated equilibrium structural parameters, shear modulus, and Young's modulus of TaB 2 are well consistent with the available experimental data, and TaB 2 with P6/mmm space group has stronger directional bonding between ions than WB 2 , OsB 2 , IrN 2 , and PtN 2 . For TaB 2 , the hexagonal P6/mmm structure is more stable than the orthorhombic Pmmn one, while for IrB 2 the orthorhombic Pmmn structure is the most stable one. The high shear modulus of P6/mmm phase TaB 2 is mainly due to the strong covalent π-bonding of B-hexagon in the (0001) plane. Such a B-hexagon network can strongly resist against an applied [112-bar0] (0001) shear deformation. Correlation between the hardness and the elastic constants of TaB 2 was discussed. The band structure shows that P6/mmm phase TaB 2 and Pmmn phase IrB 2 are both metallic. The calculations show that both TaB and IrB are elastically stable with the hexagonal P6 3 /mmc structure. - Elastic constant c 44 of TaB 2 is calculated to be 235 GPa. This value is exceptionally high, exceeding those of WB 2 , OsB 2 , WB 4 , OsN 2 , IrN 2 , and PtN 2 .

Experimental study on the effect of fill ratio on an R744 two-phase thermosyphon loop

International Nuclear Information System (INIS)

Tong, Zhen; Liu, Xiao-Hua; Li, Zhen; Jiang, Yi

2016-01-01

Highlights: • Performance of R744 two-phase thermosyphon loop is experimentally analyzed. • There are usually some fluids that circulate in the loop without changing phase. • Maximum heat transfer ability is achieved at the fill ratio around 100%. • Lowest driving temperature difference is achieved at the fill ratio around 62%. • Thermosyphon loop with a lower fill ratio is more likely to fluctuate at small heat loads. - Abstract: As a natural, environmentally friendly fluid with excellent thermodynamic and transport properties, carbon dioxide is an effective alternative refrigerant. This paper describes an experiment conducted on an R744-based two-phase thermosyphon loop (TPTL). With different fill ratios of 45~151%, the effect of fill ratio on the working performance of the R744 TPTL is investigated. To maintain the conservation of momentum, part of the fluid circulates in the loop without changing phase; this part of the fluid may be liquid, vapor, or both liquid and vapor depending on the fill ratio. This is how the R744 TPTL self-adjusts among different heat loads. The experimental results show that the working state of the R744 TPTL has a lot to do with the fill ratio. With a low fill ratio, the TPTL is more likely to fluctuate under small heat loads. When the fill ratio is around 100%, the TPTL reaches its maximum heat transfer ability, and when the fill ratio is around 62%, the lowest driving temperature difference is achieved. Considering that the fill ratio's effect on the driving temperature difference is not very significant and that pursuing maximum heat transfer ability is more meaningful, a fill ratio of around 100% is recommended.

Loop-space quantum formulation of free electromagnetism

International Nuclear Information System (INIS)

Di Bartolo, C.; Nori, F.; Gambini, R.; Trias, A.

1983-01-01

A procedure for direct quantization of free electromagnetism in the loop-space is proposed. Explicit solutions for the loop-dependent vacuum and the Wilson loop-average are given. It is shown that elementary lines of magnetic field appear as extremals in the vacuum state as a result of the regularization procedure

A totally diverting loop colostomy.

Science.gov (United States)

Merrett, N. D.; Gartell, P. C.

1993-01-01

A technique is described where the distal limb of a loop colostomy is tied with nylon or polydioxanone. This ensures total faecal diversion and dispenses with the supporting rod, enabling early application of stoma appliances. The technique does not interfere with the traditional transverse closure of a loop colostomy. PMID:8379632

Room temperature mid-IR single photon spectral imaging

DEFF Research Database (Denmark)

Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter; Pedersen, Christian

2012-01-01

Spectral imaging and detection of mid-infrared (mid-IR) wavelengths are emerging as an enabling technology of great technical and scientific interest; primarily because important chemical compounds display unique and strong mid-IR spectral fingerprints revealing valuable chemical information. Whi...... 20 % for polarized incoherent light at 3 \\mum. The proposed method is relevant for existing and new mid-IR applications like gas analysis and medical diagnostics....

On-the-fly reduction of open loops

Energy Technology Data Exchange (ETDEWEB)

Buccioni, Federico; Pozzorini, Stefano; Zoller, Max [Universitaet Zuerich, Physik-Institut, Zurich (Switzerland)

2018-01-15

Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations. (orig.)

On-the-fly reduction of open loops

Science.gov (United States)

Buccioni, Federico; Pozzorini, Stefano; Zoller, Max

2018-01-01

Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations.

Loop Quantum Cosmology.

Science.gov (United States)

Bojowald, Martin

2008-01-01

Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a classical spacetime inevitably comes to an end after a finite amount of proper time. This presents a breakdown of the classical picture and requires an extended theory for a meaningful description. Since small length scales and high curvatures are involved, quantum effects must play a role. Not only the singularity itself but also the surrounding spacetime is then modified. One particular theory is loop quantum cosmology, an application of loop quantum gravity to homogeneous systems, which removes classical singularities. Its implications can be studied at different levels. The main effects are introduced into effective classical equations, which allow one to avoid the interpretational problems of quantum theory. They give rise to new kinds of early-universe phenomenology with applications to inflation and cyclic models. To resolve classical singularities and to understand the structure of geometry around them, the quantum description is necessary. Classical evolution is then replaced by a difference equation for a wave function, which allows an extension of quantum spacetime beyond classical singularities. One main question is how these homogeneous scenarios are related to full loop quantum gravity, which can be dealt with at the level of distributional symmetric states. Finally, the new structure of spacetime arising in loop quantum gravity and its application to cosmology sheds light on more general issues, such as the nature of time. Supplementary material is available for this article at 10.12942/lrr-2008-4.

Genetic and acoustic population structuring in the Okinawa least horseshoe bat: are intercolony acoustic differences maintained by vertical maternal transmission?

Science.gov (United States)

Yoshino, Hajime; Armstrong, Kyle N; Izawa, Masako; Yokoyama, Jun; Kawata, Masakado

2008-12-01

The origin and meaning of echolocation call frequency variation within rhinolophid bats is not well understood despite an increasing number of allopatric and sympatric examples being documented. A bimodal distribution of mean regional call frequency within the Okinawa-jima Island population of Rhinolophus cornutus pumilus (Rhinolophidae) provided a unique opportunity to investigate geographic call frequency variation early in its development. Individual resting echolocation frequencies, partial mitochondrial DNA D-loop sequences and genotypes from six microsatellite loci were obtained from 288 individuals in 11 colonies across the entire length of the island, and nearby Kume-jima Island. Acoustic differences (5-8 kHz) observed between the north and south regions have been maintained despite evidence of sufficient nuclear gene flow across the middle of the island. Significant subdivision of maternally inherited D-loop haplotypes suggested a limitation of movement of females between regions, but not within the regions, and was evidence of female philopatry. These results support a 'maternal transmission' hypothesis whereby the difference in the constant frequency (CF) component between the regions is maintained by mother-offspring transmission of CF, the restricted dispersal of females between regions and small effective population size. We suggest that the mean 5-8 kHz call frequency difference between the regions might develop through random cultural drift.

Hydraulic loop: practices using open control systems

International Nuclear Information System (INIS)

Carrasco, J.A.; Alonso, L.; Sanchez, F.

1998-01-01

The Tecnatom Hydraulic Loop is a dynamic training platform. It has been designed with the purpose of improving the work in teams. With this system, the student can obtain a full scope vision of a system. The hydraulic Loop is a part of the Tecnatom Maintenance Centre. The first objective of the hydraulic Loop is the instruction in components, process and process control using open control system. All the personal of an electric power plant can be trained in the Hydraulic Loop with specific courses. The development of a dynamic tool for tests previous to plant installations has been an additional objective of the Hydraulic Loop. The use of this platform is complementary to the use of full-scope simulators in order to debug and to analyse advanced control strategies. (Author)

Osmotic mechanism of the loop extrusion process

Science.gov (United States)

Yamamoto, Tetsuya; Schiessel, Helmut

2017-09-01

The loop extrusion theory assumes that protein factors, such as cohesin rings, act as molecular motors that extrude chromatin loops. However, recent single molecule experiments have shown that cohesin does not show motor activity. To predict the physical mechanism involved in loop extrusion, we here theoretically analyze the dynamics of cohesin rings on a loop, where a cohesin loader is in the middle and unloaders at the ends. Cohesin monomers bind to the loader rather frequently and cohesin dimers bind to this site only occasionally. Our theory predicts that a cohesin dimer extrudes loops by the osmotic pressure of cohesin monomers on the chromatin fiber between the two connected rings. With this mechanism, the frequency of the interactions between chromatin segments depends on the loading and unloading rates of dimers at the corresponding sites.

Thermodynamic evaluation of chemical looping combustion for combined cooling heating and power production driven by coal

International Nuclear Information System (INIS)

Fan, Junming; Hong, Hui; Zhu, Lin; Wang, Zefeng; Jin, Hongguang

2017-01-01

Highlights: • An ex-situ coal gasification chemical looping combustion integrated with CCHP process has been presented. • This novel process maintains a maximum energy efficiency of 60.34%. • The fossil energy saving ratio of this process is optimize to be 27.20%. - Abstract: This study carries out an investigation concerning on the benefits of ex-situ coal gasification chemical looping combustion integrated with combined cooling, heating and power generation (CCHP-CLC) by means of thermodynamic evaluation. The coal gasification syngas is introduced into chemical looping combustion for inherent separation of CO_2 without extra energy consumed. The combustion flue gases from both air reactor and fuel reactor are sequentially fed into gas turbines for electricity production, a heat recovery vapor generator unit for further electricity generation with driving a LiBr-H_2O absorption chiller for cooling production in summer and finally a heat exchanger for daily heat water production. A preliminary parameter analysis helps to obtain the optimum operating condition, as steam-to-coal ratio (S/C) of 0.05, oxygen-to-coal ratio (O/C) of 0.75, and operating pressure of chemical looping combustion process of 5 bar. The overall energy efficiency of the CCHP-CLC process is calculated equal to 58.20% in summer compared with that of 60.34% in winter. Importantly, by utilization of such process, the reduction potential of fossil fuel (coal) consumption has been demonstrated to be 23.36% in summer and 27.20% in winter.

Two-Loop Scattering Amplitudes from the Riemann Sphere

CERN Document Server

Geyer, Yvonne; Monteiro, Ricardo; Tourkine, Piotr

2016-01-01

The scattering equations give striking formulae for massless scattering amplitudes at tree level and, as shown recently, at one loop. The progress at loop level was based on ambitwistor string theory, which naturally yields the scattering equations. We proposed that, for ambitwistor strings, the standard loop expansion in terms of the genus of the worldsheet is equivalent to an expansion in terms of nodes of a Riemann sphere, with the nodes carrying the loop momenta. In this paper, we show how to obtain two-loop scattering equations with the correct factorization properties. We adapt genus-two integrands from the ambitwistor string to the nodal Riemann sphere and show that these yield correct answers, by matching standard results for the four-point two-loop amplitudes of maximal supergravity and super-Yang-Mills theory. In the Yang-Mills case, this requires the loop analogue of the Parke-Taylor factor carrying the colour dependence, which includes non-planar contributions.

Free convection in a partially submerged fluid loop

International Nuclear Information System (INIS)

Britt, T.E.; Wood, D.C.

1982-01-01

Several natural convection loop systems are studied in order to determine the operational characteristics for a multiple loop container which is used to cool failed nuclear reactor assemblies. Both analytical and experimental studies were undertaken to examine flow in both circular and rectangular flow loops. It was found that when a circular loop is heated at the bottom and cooled at the top, recirculation cells form at all input power fluxes. At fluxes between 0.1 W/cm 2 and 0.7 W/cm 2 the cells caused flow oscillations and reversals. With the circular loop heated from the side, no recirculation cells were observed at the power fluxes up to 1.5 W/cm. Boiling did not occur in the circular loop. For a rectangular loop heated and cooled on its vertical sides, no recirculation cells or flow reversals were seen. At input power fluxes above 1.2 W/cm 2 , periodic boiling in the heated side caused flow oscillations

A non-perturbative study of 4d U(1) non-commutative gauge theory - the fate of one-loop instability

International Nuclear Information System (INIS)

Bietenholz, Wolfgang; Nishimura, Jun; Susaki, Yoshiaki; Volkholz, Jan

2006-01-01

Recent perturbative studies show that in 4d non-commutative spaces, the trivial (classically stable) vacuum of gauge theories becomes unstable at the quantum level, unless one introduces sufficiently many fermionic degrees of freedom. This is due to a negative IR-singular term in the one-loop effective potential, which appears as a result of the UV/IR mixing. We study such a system non-perturbatively in the case of pure U(1) gauge theory in four dimensions, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d = 2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non-commutativity parameter θ, which provides evidence for a possible continuum theory. The extent of the dynamically generated space in the non-commutative directions becomes finite in the above limit, and its dependence on θ is evaluated explicitly. We also study the dispersion relation. In the weak coupling symmetric phase, it involves a negative IR-singular term, which is responsible for the observed phase transition. In the broken phase, it reveals the existence of the Nambu-Goldstone mode associated with the spontaneous symmetry breaking

The effect of test dose and first IR stimulation temperature on post-IR IRSL measurements of rock slices

DEFF Research Database (Denmark)

Liu, Jinfeng; Murray, Andrew; Sohbati, Reza

2016-01-01

lies close to the laboratory saturation levels only for higher first IR stimulation temperatures e.g. 200°C or 250°C. Our data confirm earlier suggestions based on sand-grain measurements that, for older sam-ples, accurate measurements close to saturation require that a higher first IR temperature...

Cooling Active Region Loops Observed With SXT and TRACE

OpenAIRE

Winebarger, Amy R.; Warren, Harry P.

2005-01-01

An Impulsive Heating Multiple Strand (IHMS) Model is able to reproduce the observational characteristics of EUV (~ 1 MK) active region loops. This model implies that some of the loops must reach temperatures where X-ray filters are sensitive (> 2.5 MK) before they cool to EUV temperatures. Hence, some bright EUV loops must be preceded by bright X-ray loops. Previous analysis of X-ray and EUV active region observations, however, have concluded that EUV loops are not preceded by X-ray loops. In...

Efficacy determinants of subcutaneous microdose glucagon during closed-loop control.

Science.gov (United States)

Russell, Steven J; El-Khatib, Firas H; Nathan, David M; Damiano, Edward R

2010-11-01

During a previous clinical trial of a closed-loop blood glucose (BG) control system that administered insulin and microdose glucagon subcutaneously, glucagon was not uniformly effective in preventing hypoglycemia (BGMicrodose glucagon administration was relatively ineffective in preventing hypoglycemia when plasma insulin levels exceeded the controller's online estimate by >60%. After the algorithm PK parameters were globally adjusted, insulin dosing was more conservative and microdose glucagon administration was very effective in reducing hypoglycemia while maintaining normal plasma glucagon levels. Improvements in the accuracy of the controller's online estimate of plasma insulin levels could be achieved if ultrarapid-acting insulin formulations could be developed with faster absorption and less intra- and intersubject variability than the current insulin analogs available today. © 2010 Diabetes Technology Society.

Quantum chromodynamics as dynamics of loops

International Nuclear Information System (INIS)

Makeenko, Yu.M.; Migdal, A.A.

1981-01-01

QCD is entirely reformulated in terms of white composite fields - the traces of the loop products. The 1/N expansion turns out to be the WKB (Hartree-Fock) approximation for these fields. The 'classical' equation describing the N = infinite case is reduced tp a bootstrap form. New, manifestly gauge-invariant perturbation theory in the loop space, reproducing asymptotic freedom, is developed by iterations of this equation. The area law appears to be a self-consistent solution at large loops. (orig.)

Effects of adding Braun jejunojejunostomy to standard Whipple procedure on reduction of afferent loop syndrome - a randomized clinical trial.

Science.gov (United States)

Kakaei, Farzad; Beheshtirouy, Samad; Nejatollahi, Seyed Moahammad Reza; Rashidi, Iqbal; Asvadi, Touraj; Habibzadeh, Afshin; Oliaei-Motlagh, Mohammad

2015-12-01

Whipple surgery (pancreaticodeudenectomy) has a high complication rate. We aimed to evaluate whether adding Braun jejunojejunostomy (side-to-side anastomosis of afferent and efferent loops distal to the gastrojejunostomy site) to a standard Whipple procedure would reduce postoperative complications. We conducted a randomized clinical trial comparing patients who underwent standard Whipple surgery (standard group) and patients who underwent standard Whipple surgery with Braun jejunojejunostomy (Braun group). Patients were followed for 1 month after the procedure and postoperative complications were recorded. Our study included 30 patients: 15 in the Braun and 15 in the standard group. In the Braun group, 4 (26.7%) patients experienced 6 complications, whereas in the standard group, 7 (46.7%) patients experienced 11 complications (p = 0.14). Complications in the Braun group were gastrointestinal bleeding and wound infection (n = 1 each) and delayed gastric emptying and pulmonary infection (n = 2 each). Complications in the standard group were death, pancreatic anastomosis leak and biliary anastomosis leak (n = 1 each); gastrointestinal bleeding (n = 2); and afferent loop syndrome and delayed gastric emptying (n = 3 each). There was no significant difference between groups in the subtypes of complications. Our results showed that adding Braun jejunojejunostomy to standard Whipple procedure was associated with lower rates of afferent loop syndrome and delayed gastric emptying. However, more studies are needed to define the role of Braun jejunojejunostomy in this regard. IRCT2014020316473N1 (www.irct.ir).

IR fixed points in SU(3 gauge theories

Directory of Open Access Journals (Sweden)

K.-I. Ishikawa

2015-09-01

Full Text Available We propose a novel RG method to specify the location of the IR fixed point in lattice gauge theories and apply it to the SU(3 gauge theories with Nf fundamental fermions. It is based on the scaling behavior of the propagator through the RG analysis with a finite IR cutoff, which we cannot remove in the conformal field theories in sharp contrast to the confining theories. The method also enables us to estimate the anomalous mass dimension in the continuum limit at the IR fixed point. We perform the program for Nf=16,12,8 and Nf=7 and indeed identify the location of the IR fixed points in all cases.

The Universal One-Loop Effective Action

CERN Document Server

Drozd, Aleksandra; Quevillon, Jérémie; You, Tevong

2016-01-01

We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.

The universal one-loop effective action

International Nuclear Information System (INIS)

Drozd, Aleksandra; Ellis, John; Quevillon, Jérémie; You, Tevong

2016-01-01

We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.

Mathematical Modeling of Loop Heat Pipes

Science.gov (United States)

Kaya, Tarik; Ku, Jentung; Hoang, Triem T.; Cheung, Mark L.

1998-01-01

The primary focus of this study is to model steady-state performance of a Loop Heat Pipe (LHP). The mathematical model is based on the steady-state energy balance equations at each component of the LHP. The heat exchange between each LHP component and the surrounding is taken into account. Both convection and radiation environments are modeled. The loop operating temperature is calculated as a function of the applied power at a given loop condition. Experimental validation of the model is attempted by using two different LHP designs. The mathematical model is tested at different sink temperatures and at different elevations of the loop. Tbc comparison of the calculations and experimental results showed very good agreement (within 3%). This method proved to be a useful tool in studying steady-state LHP performance characteristics.

Loop expansion in massless three-dimensional QED

International Nuclear Information System (INIS)

Guendelman, E.I.; Radulovic, Z.M.

1983-01-01

It is shown how the loop expansion in massless three-dimensional QED can be made finite, up to three loops, by absorbing the infrared divergences in a gauge-fixing term. The same method removes leading and first subleading singularities to all orders of perturbation theory, and all singularities of the fermion self-energy to four loops

Summary of TRUEX Radiolysis Testing Using the INL Radiolysis Test Loop

Energy Technology Data Exchange (ETDEWEB)

Dean R. Peterman; Lonnie G. Olson; Rocklan G. McDowell; Gracy Elias; Jack D. Law

2012-03-01

The INL radiolysis and hydrolysis test loop has been used to evaluate the effects of hydrolytic and radiolytic degradation upon the efficacy of the TRUEX flowsheet for the recovery of trivalent actinides and lanthanides from acidic solution. Repeated irradiation and subsequent re-conditioning cycles did result in a significant decrease in the concentration of the TBP and CMPO extractants in the TRUEX solvent and a corresponding decrease in americium and europium extraction distributions. However, the build-up of solvent degradation products upon {gamma}-irradiation, had little impact upon the efficiency of the stripping section of the TRUEX flowsheet. Operation of the TRUEX flowsheet would require careful monitoring to ensure extraction distributions are maintained at acceptable levels.

Different roles of eukaryotic MutS and MutL complexes in repair of small insertion and deletion loops in yeast.

Directory of Open Access Journals (Sweden)

Nina V Romanova

2013-10-01

Full Text Available DNA mismatch repair greatly increases genome fidelity by recognizing and removing replication errors. In order to understand how this fidelity is maintained, it is important to uncover the relative specificities of the different components of mismatch repair. There are two major mispair recognition complexes in eukaryotes that are homologues of bacterial MutS proteins, MutSα and MutSβ, with MutSα recognizing base-base mismatches and small loop mispairs and MutSβ recognizing larger loop mispairs. Upon recognition of a mispair, the MutS complexes then interact with homologues of the bacterial MutL protein. Loops formed on the primer strand during replication lead to insertion mutations, whereas loops on the template strand lead to deletions. We show here in yeast, using oligonucleotide transformation, that MutSα has a strong bias toward repair of insertion loops, while MutSβ has an even stronger bias toward repair of deletion loops. Our results suggest that this bias in repair is due to the different interactions of the MutS complexes with the MutL complexes. Two mutants of MutLα, pms1-G882E and pms1-H888R, repair deletion mispairs but not insertion mispairs. Moreover, we find that a different MutL complex, MutLγ, is extremely important, but not sufficient, for deletion repair in the presence of either MutLα mutation. MutSβ is present in many eukaryotic organisms, but not in prokaryotes. We suggest that the biased repair of deletion mispairs may reflect a critical eukaryotic function of MutSβ in mismatch repair.

Improvenments in environmental trace analysis by GC-IR and LC-IR.

NARCIS (Netherlands)

Visser, T.; Vredenbregt, M.J.; Jong, A.P.J.M.; Somsen, G.W.; Hankemeier, T.; Velthorst, N.H.; Gooijer, C.; Brinkman, U.A.T.

1997-01-01

Research has been carried out to enlarge the potential of infrared (IR) spectrometry as a detector in gas and liquid chromatography (GC and LC). The study has been directed to applications in environmental analysis. Examples of recently obtained results are presented. The analyte detectability of

Ligand binding affinity at the insulin receptor isoform A (IR-A and subsequent IR-A tyrosine phosphorylation kinetics are important determinants of mitogenic biological outcomes.

Directory of Open Access Journals (Sweden)

Harinda eRajapaksha

2015-07-01

Full Text Available The insulin receptor (IR is a tyrosine kinase receptor that can mediate both metabolic and mitogenic biological actions. The IR isoform-A (IR-A arises from alternative splicing of exon 11 and has different ligand binding and signalling properties compared to the IR isoform-B. The IR-A not only binds insulin but also insulin-like growth factor-II (IGF-II with high affinity. IGF-II acting through the IR-A promotes cancer cell proliferation, survival and migration by activating some unique signalling molecules compared to those activated by insulin. This observation led us to investigate whether the different IR-A signalling outcomes in response to IGF-II and insulin could be attributed to phosphorylation of a different subset of IR-A tyrosine residues or to the phosphorylation kinetics. We correlated IR-A phosphorylation to activation of molecules involved in mitogenic and metabolic signalling (MAPK and Akt and receptor internalisation rates (related to mitogenic signalling. We also extended this study to incorporate two ligands that are known to promote predominantly mitogenic ([His4, Tyr15, Thr49, Ile51] IGF-I, qIGF-I or metabolic (S597 peptide biological actions, to see if common mechanisms can be used to define mitogenic or metabolic signalling through the IR-A. The 3-fold lower mitogenic action of IGF-II compared to insulin was associated with a decreased potency in activation of Y960, Y1146, Y1150, Y1151, Y1316 and Y1322, in MAPK phosphorylation and in IR-A internalization. With the poorly mitogenic S597 peptide it was a decreased rate of tyrosine phosphorylation rather than potency that was associated with a low mitogenic potential. We conclude that both decreased affinity of IR-A binding and the kinetics of IR-A phosphorylation can independently lead to a lower mitogenic activity. None of the studied parameters could account for the lower metabolic activity of qIGF-I.

Measurement of the Ir-191,193(n,2n)Ir-190,192 Reaction Cross Section Between 9.0 and 16.5 MeV

Science.gov (United States)

Wildenhain, Elizabeth; Finch, Sean; Tornow, Werner; Krishichayan, F.

2017-09-01

Iridium is one of the elements prioritized by Nonproliferation and Homeland Security agencies. In addition, Ir-192 is being used in various medical treatments. Improved data and corresponding evaluations of neutron-induced reactions on the iridium isotopes are required to meet the demands of several applications of societal interest. This study measured the cross section of the Ir-191,193(n, 2n)Ir-190,192 reactions at energies from 9.0 to 16.5 MeV using the activation technique. Natural Ir samples [Ir-191 37.3%, Ir-193 62.7%] were sandwiched between Au-197 monitor foils and irradiated with monoenergetic neutron beams at the tandem facility of the Triangle Universities Nuclear Laboratory (TUNL). Gamma rays from the irradiated samples were counted in TUNL's low background facility using high-efficient HPGe detectors. Measured cross-section data are compared to previous data and to predictions from nuclear data libraries (e.g. ENDF). Research at TUNL funded by the NSF.

Ilgalaikių bedarbių karjeros projektavimo socialiniai ir psichologiniai veiksniai

OpenAIRE

Noreikienė, Ligita

2009-01-01

Darbas yra viena iš pagrindinių žmogaus vertybių. Jis suteikia kiekvienam saviraiškos galimybę, didina saugumo jausmą ir padeda kurti materialinę gerovę. Bedarbystė – rimta socialinė ir psichologinė darbo neturinčio žmogaus problema. Nepakankamos investicijos į pramonės, paslaugų, transporto ir statybos sektorius sukuria perteklinę darbo jėgą ir didina nedarbą. Padidėjus bendram nedarbui, visada išauga ilgalaikė bedarbystė. Ilgalaikio nedarbo metu prarandama turėta kvalifikacija ir gebėjimai...

Near-IR imaging of cracks in teeth

Science.gov (United States)

Fried, William A.; Simon, Jacob C.; Lucas, Seth; Chan, Kenneth H.; Darling, Cynthia L.; Staninec, Michal; Fried, Daniel

2014-02-01

Dental enamel is highly transparent at near-IR wavelengths and several studies have shown that these wavelengths are well suited for optical transillumination for the detection and imaging of tooth decay. We hypothesize that these wavelengths are also well suited for imaging cracks in teeth. Extracted teeth with suspected cracks were imaged at several wavelengths in the near-IR from 1300-1700-nm. Extracted teeth were also examined with optical coherence tomography to confirm the existence of suspected cracks. Several teeth of volunteers were also imaged in vivo at 1300-nm to demonstrate clinical potential. In addition we induced cracks in teeth using a carbon dioxide laser and imaged crack formation and propagation in real time using near-IR transillumination. Cracks were clearly visible using near-IR imaging at 1300-nm in both in vitro and in vivo images. Cracks and fractures also interfered with light propagation in the tooth aiding in crack identification and assessment of depth and severity.

Data in support of FSH induction of IRS-2 in human granulosa cells: Mapping the transcription factor binding sites in human IRS-2 promoter

Directory of Open Access Journals (Sweden)

Surleen Kaur

2016-03-01

Full Text Available Insulin receptor substrate-2 (IRS-2 plays critical role in the regulation of various metabolic processes by insulin and IGF-1. The defects in its expression and/or function are linked to diseases like polycystic ovary syndrome (PCOS, insulin resistance and cancer. To predict the transcription factors (TFs responsible for the regulation of human IRS-2 gene expression, the transcription factor binding sites (TFBS and the corresponding TFs were investigated by analysis of IRS-2 promoter sequence using MatInspector Genomatix software (Cartharius et al., 2005 [1]. The ibid data is part of author׳s publication (Anjali et al., 2015 [2] that explains Follicle stimulating hormone (FSH mediated IRS-2 promoter activation in human granulosa cells and its importance in the pathophysiology of PCOS. Further analysis was carried out for binary interactions of TF regulatory genes in IRS-2 network using Cytoscape software tool and R-code. In this manuscript, we describe the methodology used for the identification of TFBSs in human IRS-2 promoter region and provide details on experimental procedures, analysis method, validation of data and also the raw files. The purpose of this article is to provide the data on all TFBSs in the promoter region of human IRS-2 gene as it has the potential for prediction of the regulation of IRS-2 gene in normal or diseased cells from patients with metabolic disorders and cancer. Keywords: IRS-2, TFBS, FSH, SP1, ChIP

A LabVIEW model incorporating an open-loop arterial impedance and a closed-loop circulatory system.

Science.gov (United States)

Cole, R T; Lucas, C L; Cascio, W E; Johnson, T A

2005-11-01

While numerous computer models exist for the circulatory system, many are limited in scope, contain unwanted features or incorporate complex components specific to unique experimental situations. Our purpose was to develop a basic, yet multifaceted, computer model of the left heart and systemic circulation in LabVIEW having universal appeal without sacrificing crucial physiologic features. The program we developed employs Windkessel-type impedance models in several open-loop configurations and a closed-loop model coupling a lumped impedance and ventricular pressure source. The open-loop impedance models demonstrate afterload effects on arbitrary aortic pressure/flow inputs. The closed-loop model catalogs the major circulatory waveforms with changes in afterload, preload, and left heart properties. Our model provides an avenue for expanding the use of the ventricular equations through closed-loop coupling that includes a basic coronary circuit. Tested values used for the afterload components and the effects of afterload parameter changes on various waveforms are consistent with published data. We conclude that this model offers the ability to alter several circulatory factors and digitally catalog the most salient features of the pressure/flow waveforms employing a user-friendly platform. These features make the model a useful instructional tool for students as well as a simple experimental tool for cardiovascular research.

The design of in-pile test section for fuel test loop

Energy Technology Data Exchange (ETDEWEB)

Park, K. N.; Lee, J. M.; Shim, B. S.; Zee, D. Y.; Park, S. H.; Ahn, S. H.; Lee, J. Y.; Kim, Y. J. [KAERI, Taejon (Korea, Republic of)

2004-07-01

As an equipment for nuclear fuel's general performance irradiation test in HANARO, Fuel Test Loop(FTL) has been developed that can irradiate the pin to the maximum number of 3 at the core irradiation hole(IR1 hole) by considering for it's utility and user's irradiation requirement. 3-Pin FTL consists of In-Pile Test Section (IPS) and Out-of-Pile System (OPS). IPS consists for IPS Vessel assembly, In-Pool Piping, IPS Support, In-Pool Piping Support etc. Design that such IPS considers interference item consisted to do not bear in existing facilities by one. IVA that is connected to the OPS are controlled and regulated by means of system pressure, system temperature and the water quality. IPS Vessel assembly is consisted of outer pressure vessel, inner pressure vessel, IPS head, inner assembly and test fuel carrier. After 3-Pin FTL development which is expected to be finished by the 2006, FTL will be used for the irradiation test of the new PWR-type fuel and can maximize the usage of HANARO.

Mechanical evaluation of space closure loops in orthodontics.

Science.gov (United States)

Rodrigues, Eduardo Uggeri; Maruo, Hiroshi; Guariza Filho, Odilon; Tanaka, Orlando; Camargo, Elisa Souza

2011-01-01

This study evaluated the mechanical performance of teardrop-shaped loops and teardrop-shaped loops with helix used in orthodontic space closure. Sixty retraction loops made with 0.019" x 0.025" stainless steel (SS) and beta-titanium (BT) wires were used. They were attached to a testing machine to measure the magnitudes of the sagittal force and the load-deflection ratio necessary for 1 mm, 2 mm and 3 mm activation. The results demonstrated that the BT alloy presented significantly smaller mean values (p < 0.01) of sagittal force and load-deflection than the SS alloy. The loop with the highest mean value of sagittal force and load-deflection was the teardrop-shaped loop (p < 0.01). Differences were observed in the mean values of sagittal force and load-deflection among activations, and the highest mean value was found in the activation of 3 mm, while the smallest mean value was evident in the activation of 1 mm (p < 0.01). It could be concluded that the metallic alloy used and the presence of a helix in configuration of the loops may have a strong influence on the sagittal force produced and on the load-deflection ratio; the teardrop-shaped loops and teardrop-shaped loops with helix in BT presented the release of lighter forces; the teardrop-shaped loop in SS generated a high load-deflection ratio, providing high magnitudes of horizontal force during its deactivation.

Mechanical evaluation of space closure loops in Orthodontics

Directory of Open Access Journals (Sweden)

Eduardo Uggeri Rodrigues

2011-02-01

Full Text Available This study evaluated the mechanical performance of teardrop-shaped loops and teardrop-shaped loops with helix used in orthodontic space closure. Sixty retraction loops made with 0.019" x 0.025" stainless steel (SS and beta-titanium (BT wires were used. They were attached to a testing machine to measure the magnitudes of the sagittal force and the load-deflection ratio necessary for 1 mm, 2 mm and 3 mm activation. The results demonstrated that the BT alloy presented significantly smaller mean values (p < 0.01 of sagittal force and load-deflection than the SS alloy. The loop with the highest mean value of sagittal force and load-deflection was the teardrop-shaped loop (p < 0.01. Differences were observed in the mean values of sagittal force and load-deflection among activations, and the highest mean value was found in the activation of 3 mm, while the smallest mean value was evident in the activation of 1 mm (p < 0.01. It could be concluded that the metallic alloy used and the presence of a helix in configuration of the loops may have a strong influence on the sagittal force produced and on the load-deflection ratio; the teardrop-shaped loops and teardrop-shaped loops with helix in BT presented the release of lighter forces; the teardrop-shaped loop in SS generated a high load-deflection ratio, providing high magnitudes of horizontal force during its deactivation.

Protein Loop Structure Prediction Using Conformational Space Annealing.

Science.gov (United States)

Heo, Seungryong; Lee, Juyong; Joo, Keehyoung; Shin, Hang-Cheol; Lee, Jooyoung

2017-05-22

We have developed a protein loop structure prediction method by combining a new energy function, which we call E PLM (energy for protein loop modeling), with the conformational space annealing (CSA) global optimization algorithm. The energy function includes stereochemistry, dynamic fragment assembly, distance-scaled finite ideal gas reference (DFIRE), and generalized orientation- and distance-dependent terms. For the conformational search of loop structures, we used the CSA algorithm, which has been quite successful in dealing with various hard global optimization problems. We assessed the performance of E PLM with two widely used loop-decoy sets, Jacobson and RAPPER, and compared the results against the DFIRE potential. The accuracy of model selection from a pool of loop decoys as well as de novo loop modeling starting from randomly generated structures was examined separately. For the selection of a nativelike structure from a decoy set, E PLM was more accurate than DFIRE in the case of the Jacobson set and had similar accuracy in the case of the RAPPER set. In terms of sampling more nativelike loop structures, E PLM outperformed E DFIRE for both decoy sets. This new approach equipped with E PLM and CSA can serve as the state-of-the-art de novo loop modeling method.

Effect of Loop Diameter on the Steady State and Stability Behaviour of Single-Phase and Two-Phase Natural Circulation Loops

Directory of Open Access Journals (Sweden)

P. K. Vijayan

2008-01-01

Full Text Available In natural circulation loops, the driving force is usually low as it depends on the riser height which is generally of the order of a few meters. The heat transport capability of natural circulation loops (NCLs is directly proportional to the flow rate it can generate. With low driving force, the straightforward way to enhance the flow is to reduce the frictional losses. A simple way to do this is to increase the loop diameter which can be easily adopted in pressure tube designs such as the AHWR and the natural circulation boilers employed in fossil-fuelled power plants. Further, the loop diameter also plays an important role on the stability behavior. An extensive experimental and theoretical investigation of the effect of loop diameter on the steady state and stability behavior of single- and two-phase natural circulation loops have been carried out and the results of this study are presented in this paper.

UPTF loop seal tests and their RELAP simulation

International Nuclear Information System (INIS)

Tuomainen, M.; Tuunanen, J.

1997-01-01

In a pressurized water reactor the loop seals have an effect on the natural circulation. If a loop seal is filled with water it can cause a flow stagnation in the loop during two-phase natural circulation. Also the pressure loss over a filled loop seal is high, which lowers the water level in the core. Tests to investigate the loop seal behaviour were performed on a German Upper Plenum Test Facility (UPTF). The purpose of the tests was to study the amount of water in the loop seal under different steam flow rates. The tests were simulated with RELAP5/MOD3.2. With high steam flow rates the code had problems in simulating the amount of the water remaining in the pump elbow, but in general the agreement between the calculated results and the experimental data was good. (orig.)

SU(2) string tension from large Wilson loops

International Nuclear Information System (INIS)

Karsch, F.; Lang, C.B.

1984-01-01

We determine expectation values of Wilson loops and correlations of Polyakov loops on lattices of size 10 X 16 3 and 8 X 16 3 at β values 2.25 and 2.375. Utilizing a recently proposed method to reduce the variance of loop expectation values, we are able to measure loops up to 6 X 6. We find Λsub(L) = 0.0151 +- 0.0006√sub(K) at β = 2.375. (orig.)

Editorial. Kultūros reiškiniai šiuolaikinių informacijos ir komunikacijos technologijų sąlygomis: nuo meno ir televizijos iki politikos

Directory of Open Access Journals (Sweden)

Jovilė Barevičiūtė

2015-10-01

Full Text Available Šiame žurnalo numeryje aptariami kai kurie daugiaaspekčiai šiuolaikinės kultūros reiškiniai, apimant tokius jų, kaip menas, televizija, politika ir kt. Medijos ir komunikacija nūdien intensyviai skverbiasi kone į visas darbo ir laisvalaikio veiklos, viešojo ir privataus sektorių sritis, reprezentuodamos dinamišką ir netolygią gyvenamojo pasaulio tikrovę. Medijuotoji komunikacija vis labiau tampa dominuojančia socializacijos forma, ji išstumia gyvąją komunikaciją: kuo toliau, tuo labiau šis reiškinys nusako ne tik jaunimo, bet ir brandaus amžiaus žmonių šiandienį bendravimo būdą. Tad akivaizdu, kad XXI a. žmogus vis labiau pasineria į įvairių medijų tinklus, apraizgančius jo gyvenimą ir tampančius pagrindine socialios ir visavertės eg zistencijos sąlyga. Tokios socialinės institucijos, kaip menas, televizija, politika, religija, šeima ir daugelis kitų, nūdien jau nebėra tokios savarankiškos, kaip, tarkime, prieš dešimt, dvidešimt ar daugiau metų. Jų suverenitetą daugiausia transformuoja būtent medijos, šioms institucijoms diktuojančios savas sąlygas ir primetančios savas taisykles. Kitaip tariant, medijos tampa tokios galingos, kad ima steigti savuosius dėsnius, kuriems vis labiau paklūsta tradicinė gyvosios socializacijos aplinka. Taip kyla daugybė diskutuotinų ir ginčytinų klausimų, paliečiančių socialinių institucijų apibrėžties, autonomijos ir suvereniteto aspektus. Šiuos aspektus iš įvairių perspektyvų gvildena ir šio numerio autoriai. Eugenija Krukauskienė ir Viktorija Žilinskaitė-Vytienė savo straipsnyje aptaria kultūros vartojimo klausimus tirdamos, kaip šiuolaikinio lietuviškojo kino meno pavyzdžius suvokia ir vertina tam tikrų amžiaus kategorijų jaunimas. Algis Mickūnas gilinasi į filosofinius šiuolaikinių diskursų klausimus, pasirinkdamas kūniškumo, lytėjimo ir taktilikos aspektus, glaudžiai susijusius su medijuotosios komunikacijos tema

The design and application of a multi-band IR imager

Science.gov (United States)

Li, Lijuan

2018-02-01

Multi-band IR imaging system has many applications in security, national defense, petroleum and gas industry, etc. So the relevant technologies are getting more and more attention in rent years. As we know, when used in missile warning and missile seeker systems, multi-band IR imaging technology has the advantage of high target recognition capability and low false alarm rate if suitable spectral bands are selected. Compared with traditional single band IR imager, multi-band IR imager can make use of spectral features in addition to space and time domain features to discriminate target from background clutters and decoys. So, one of the key work is to select the right spectral bands in which the feature difference between target and false target is evident and is well utilized. Multi-band IR imager is a useful instrument to collect multi-band IR images of target, backgrounds and decoys for spectral band selection study at low cost and with adjustable parameters and property compared with commercial imaging spectrometer. In this paper, a multi-band IR imaging system is developed which is suitable to collect 4 spectral band images of various scenes at every turn and can be expanded to other short-wave and mid-wave IR spectral bands combination by changing filter groups. The multi-band IR imaging system consists of a broad band optical system, a cryogenic InSb large array detector, a spinning filter wheel and electronic processing system. The multi-band IR imaging system's performance is tested in real data collection experiments.

Incremental Closed-loop Identification of Linear Parameter Varying Systems

DEFF Research Database (Denmark)

Bendtsen, Jan Dimon; Trangbæk, Klaus

2011-01-01

, closed-loop system identification is more difficult than open-loop identification. In this paper we prove that the so-called Hansen Scheme, a technique known from linear time-invariant systems theory for transforming closed-loop system identification problems into open-loop-like problems, can be extended...

Studying DNA looping by single-molecule FRET.

Science.gov (United States)

Le, Tung T; Kim, Harold D

2014-06-28

Bending of double-stranded DNA (dsDNA) is associated with many important biological processes such as DNA-protein recognition and DNA packaging into nucleosomes. Thermodynamics of dsDNA bending has been studied by a method called cyclization which relies on DNA ligase to covalently join short sticky ends of a dsDNA. However, ligation efficiency can be affected by many factors that are not related to dsDNA looping such as the DNA structure surrounding the joined sticky ends, and ligase can also affect the apparent looping rate through mechanisms such as nonspecific binding. Here, we show how to measure dsDNA looping kinetics without ligase by detecting transient DNA loop formation by FRET (Fluorescence Resonance Energy Transfer). dsDNA molecules are constructed using a simple PCR-based protocol with a FRET pair and a biotin linker. The looping probability density known as the J factor is extracted from the looping rate and the annealing rate between two disconnected sticky ends. By testing two dsDNAs with different intrinsic curvatures, we show that the J factor is sensitive to the intrinsic shape of the dsDNA.

NO Reactions Over Ir-Based Catalysts in the Presence of O2

Directory of Open Access Journals (Sweden)

Mingxin Guo

2011-01-01

Full Text Available The behaviour of a series of Ir-based catalysts supported on SiO2, ZSM-5 and γ-Al2O3 with various Ir loadings prepared by impregnation method was conducted by temperature programmed reaction (TPR technique. The result implies that NO is oxidized to NO2 while simultaneously being reduced to N2 or N2O in the NO reactions over iridium catalysts. The surface active phase over iridium catalysts that promote the NO reactions is IrO2. The catalytic activity increases with the increase of the Ir loading and support materials have a little effect on the catalytic activity. When the loading is less than 0.1%, the catalytic activity was found to be dependent on the nature of support materials and in order: Ir/ZSM-5>Ir/γ-Al2O3>Ir/SiO2. When the loading is higher than 0.1%, the catalytic activity for NO oxidation is in order: Ir/ZSM-5>Ir/SiO2>Ir/γ -Al2O3, which is correlated with Ir dispersion on the surface of support materials and the catalytic activity for NO reduction is in sequence: Ir/γ -Al2O3>Ir/SiO2>Ir/ZSM-5, which is attributed to the adsorbed-dissociation of NO2. Compared to Pt/γ-Al2O3, Ir/γ-Al2O3 catalyst is more benefit for the NO reduction.

Process/Equipment Co-Simulation on Syngas Chemical Looping Process

Energy Technology Data Exchange (ETDEWEB)

Zeng, Liang; Zhou, Qiang; Fan, Liang-Shih

2012-09-30

The chemical looping strategy for fossil energy applications promises to achieve an efficient energy conversion system for electricity, liquid fuels, hydrogen and/or chemicals generation, while economically separate CO{sub 2} by looping reaction design in the process. Chemical looping particle performance, looping reactor engineering, and process design and applications are the key drivers to the success of chemical looping process development. In order to better understand and further scale up the chemical looping process, issues such as cost, time, measurement, safety, and other uncertainties need to be examined. To address these uncertainties, advanced reaction/reactor modeling and process simulation are highly desired and the modeling efforts can accelerate the chemical looping technology development, reduce the pilot-scale facility design time and operating campaigns, as well as reduce the cost and technical risks. The purpose of this work is thus to conduct multiscale modeling and simulations on the key aspects of chemical looping technology, including particle reaction kinetics, reactor design and operation, and process synthesis and optimization.

Perception as a closed-loop convergence process.

Science.gov (United States)

Ahissar, Ehud; Assa, Eldad

2016-05-09

Perception of external objects involves sensory acquisition via the relevant sensory organs. A widely-accepted assumption is that the sensory organ is the first station in a serial chain of processing circuits leading to an internal circuit in which a percept emerges. This open-loop scheme, in which the interaction between the sensory organ and the environment is not affected by its concurrent downstream neuronal processing, is strongly challenged by behavioral and anatomical data. We present here a hypothesis in which the perception of external objects is a closed-loop dynamical process encompassing loops that integrate the organism and its environment and converging towards organism-environment steady-states. We discuss the consistency of closed-loop perception (CLP) with empirical data and show that it can be synthesized in a robotic setup. Testable predictions are proposed for empirical distinction between open and closed loop schemes of perception.

Feedback Loop Gains and Feedback Behavior (1996)

DEFF Research Database (Denmark)

Kampmann, Christian Erik

2012-01-01

Linking feedback loops and system behavior is part of the foundation of system dynamics, yet the lack of formal tools has so far prevented a systematic application of the concept, except for very simple systems. Having such tools at their disposal would be a great help to analysts in understanding...... large, complicated simulation models. The paper applies tools from graph theory formally linking individual feedback loop strengths to the system eigenvalues. The significance of a link or a loop gain and an eigenvalue can be expressed in the eigenvalue elasticity, i.e., the relative change...... of an eigenvalue resulting from a relative change in the gain. The elasticities of individual links and loops may be found through simple matrix operations on the linearized system. Even though the number of feedback loops can grow rapidly with system size, reaching astronomical proportions even for modest systems...

[HOMA-IR in patients with chronic hepatitis C].

Science.gov (United States)

Botshorishvili, T; Vashakidze, E

2012-02-01

The aim of investigation was to study the frequency of IR in type of viral hepatitis C, correlation with the degree of hepatic lesion and liver cirrhosis. 130 patients were investigated: 20 with acute hepatitis C; 38 with chronic hepatitis C; 72 with cirrhosis: among them 10 with Stage A, 14 with Stage B and 48 with Stage C. Also we used 30 healthy people as the controls. The study demonstrates significant changes of insulin, glucose, HOMA-IR type of viral hepatitis C, correlation with the degree of hepatic lesion and liver cirrhosis. In patients with liver cirrhosis levels of HOMA-IR is higher than in patients with chronic hepatitis C. In patients with acute hepatitis C levels of HOMA-IR was normal as in the control group. The results showed that various types of chronic viral hepatitis C and stages of cirrhosis set to increase HOMA-IR versus the controls., which were the most prominent in cases of severe hepatic lesion, which indicates that insulin resistance is a frequent companion of CHC.

Two-Loop Splitting Amplitudes

International Nuclear Information System (INIS)

Bern, Z.

2004-01-01

Splitting amplitudes govern the behavior of scattering amplitudes at the momenta of external legs become collinear. In this talk we outline the calculation of two-loop splitting amplitudes via the unitarity sewing method. This method retains the simple factorization properties of light-cone gauge, but avoids the need for prescriptions such as the principal value or Mandelstam-Leibbrandt ones. The encountered loop momentum integrals are then evaluated using integration-by-parts and Lorentz invariance identities. We outline a variety of applications for these splitting amplitudes

Two-loop splitting amplitudes

International Nuclear Information System (INIS)

Bern, Z.; Dixon, L.J.; Kosower, D.A.

2004-01-01

Splitting amplitudes govern the behavior of scattering amplitudes at the momenta of external legs become collinear. In this talk we outline the calculation of two-loop splitting amplitudes via the unitarity sewing method. This method retains the simple factorization properties of light-cone gauge, but avoids the need for prescriptions such as the principal value or Mandelstam-Leibbrandt ones. The encountered loop momentum integrals are then evaluated using integration-by-parts and Lorentz invariance identities. We outline a variety of applications for these splitting amplitudes

Ankyrin repeat and SOCS box containing protein 4 (Asb-4 colocalizes with insulin receptor substrate 4 (IRS4 in the hypothalamic neurons and mediates IRS4 degradation

Directory of Open Access Journals (Sweden)

Xia Zefeng

2011-09-01

Full Text Available Abstract Background The arcuate nucleus of the hypothalamus regulates food intake. Ankyrin repeat and SOCS box containing protein 4 (Asb-4 is expressed in neuropeptide Y and proopiomelanocortin (POMC neurons in the arcuate nucleus, target neurons in the regulation of food intake and metabolism by insulin and leptin. However, the target protein(s of Asb-4 in these neurons remains unknown. Insulin receptor substrate 4 (IRS4 is an adaptor molecule involved in the signal transduction by both insulin and leptin. In the present study we examined the colocalization and interaction of Asb-4 with IRS4 and the involvement of Asb-4 in insulin signaling. Results In situ hybridization showed that the expression pattern of Asb-4 was consistent with that of IRS4 in the rat brain. Double in situ hybridization showed that IRS4 colocalized with Asb-4, and both Asb-4 and IRS4 mRNA were expressed in proopiomelanocortin (POMC and neuropeptide Y (NPY neurons within the arcuate nucleus of the hypothalamus. In HEK293 cells co-transfected with Myc-tagged Asb-4 and Flag-tagged IRS4, Asb-4 co-immunoprecipitated with IRS4; In these cells endogenous IRS4 also co-immunoprecipitated with transfected Myc-Asb-4; Furthermore, Asb-4 co-immunoprecipitated with IRS4 in rat hypothalamic extracts. In HEK293 cells over expression of Asb-4 decreased IRS4 protein levels and deletion of the SOCS box abolished this effect. Asb-4 increased the ubiquitination of IRS4; Deletion of SOCS box abolished this effect. Expression of Asb-4 decreased both basal and insulin-stimulated phosphorylation of AKT at Thr308. Conclusions These data demonstrated that Asb-4 co-localizes and interacts with IRS4 in hypothalamic neurons. The interaction of Asb-4 with IRS4 in cell lines mediates the degradation of IRS4 and decreases insulin signaling.

Upconversion imager measures single mid-IR photons

DEFF Research Database (Denmark)

Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter; Pedersen, Christian

2013-01-01

the performance of today's state of the art IR detectors for the visible/near-IR region shows a striking contrast, as the latter can have dark currents in the range of 0.001 electrons per second. Demonstrated performance of waveguide upconversion techniques still show considerable dark noise, even when working...

Results from GRACE/SUSY at one-loop

International Nuclear Information System (INIS)

Fujimoto, J.; Ishikawa, T.; Kurihara, Y.; Jimbo, M.; Yasui, Y.; Kaneko, T.; Kon, T.; Kuroda, M.; Shimizu, Y.

2007-01-01

We report the recent development on the SUSY calculations with the help of GRACE system. GRACE/SUSY/1LOOP is the computer code which can generate Feynman diagrams in the MSSM automatically and compute one-loop amplitudes in the numerical way. We present new results of various two-body widths and chargino pair production at ILC (international linear collider) at one-loop level. (author)

LMFBR with booster pump in pumping loop

International Nuclear Information System (INIS)

Rubinstein, H.J.

1975-01-01

A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation

Oferta ir akceptas vartojimo sutartyse

OpenAIRE

Ežerskytė, Ramunė

2011-01-01

Sutarčiai sudaryti paprastai reikia, kad viena šalis pasiūlytų sudaryti sutartį (oferta), o kita šalis sutiktų su pasiūlymu (akceptas). Sutarčių įvairovėje išskiriamos vartojimo sutartys, kurios dėl silpnesnės šalies apsaugos principo įgyvendinimo pasižymi tam tikrais ypatumais. Vartojimo sutarčių sudarymas pateikiant ofertą ir akceptą yra šio magistro baigiamojo darbo objektas. Magistro baigiamąjį darbą sudaro trys dalys. Pirmojoje darbo dalyje analizuojama vartojimo sutarties sąvoka ir spec...

A non-perturbative study of 4d U(1) non-commutative gauge theory — the fate of one-loop instability

Science.gov (United States)

Bietenholz, Wolfgang; Nishimura, Jun; Susaki, Yoshiaki; Volkholz, Jan

2006-10-01

Recent perturbative studies show that in 4d non-commutative spaces, the trivial (classically stable) vacuum of gauge theories becomes unstable at the quantum level, unless one introduces sufficiently many fermionic degrees of freedom. This is due to a negative IR-singular term in the one-loop effective potential, which appears as a result of the UV/IR mixing. We study such a system non-perturbatively in the case of pure U(1) gauge theory in four dimensions, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d = 2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non-commutativity parameter θ, which provides evidence for a possible continuum theory. The extent of the dynamically generated space in the non-commutative directions becomes finite in the above limit, and its dependence on θ is evaluated explicitly. We also study the dispersion relation. In the weak coupling symmetric phase, it involves a negative IR-singular term, which is responsible for the observed phase transition. In the broken phase, it reveals the existence of the Nambu-Goldstone mode associated with the spontaneous symmetry breaking.

Computational advantages of reverberating loops for sensorimotor learning.

Science.gov (United States)

Fortney, Kristen; Tweed, Douglas B

2012-03-01

When we learn something new, our brain may store the information in synapses or in reverberating loops of electrical activity, but current theories of motor learning focus almost entirely on the synapses. Here we show that loops could also play a role and would bring advantages: loop-based algorithms can learn complex control tasks faster, with exponentially fewer neurons, and avoid the problem of weight transport. They do all this at a cost: in the presence of long feedback delays, loop algorithms cannot control very fast movements, but in this case, loop and synaptic mechanisms can complement each other-mixed systems quickly learn to make accurate but not very fast motions and then gradually speed up. Loop algorithms explain aspects of consolidation, the role of attention, and the relapses that are sometimes seen after a task has apparently been learned, and they make further predictions.

Innovative hybrid pile oscillator technique in the Minerve reactor: open loop vs. closed loop

Science.gov (United States)

Geslot, Benoit; Gruel, Adrien; Bréaud, Stéphane; Leconte, Pierre; Blaise, Patrick

2018-01-01

Pile oscillator techniques are powerful methods to measure small reactivity worth of isotopes of interest for nuclear data improvement. This kind of experiments has long been implemented in the Mineve experimental reactor, operated by CEA Cadarache. A hybrid technique, mixing reactivity worth estimation and measurement of small changes around test samples is presented here. It was made possible after the development of high sensitivity miniature fission chambers introduced next to the irradiation channel. A test campaign, called MAESTRO-SL, took place in 2015. Its objective was to assess the feasibility of the hybrid method and investigate the possibility to separate mixed neutron effects, such as fission/capture or scattering/capture. Experimental results are presented and discussed in this paper, which focus on comparing two measurements setups, one using a power control system (closed loop) and another one where the power is free to drift (open loop). First, it is demonstrated that open loop is equivalent to closed loop. Uncertainty management and methods reproducibility are discussed. Second, results show that measuring the flux depression around oscillated samples provides valuable information regarding partial neutron cross sections. The technique is found to be very sensitive to the capture cross section at the expense of scattering, making it very useful to measure small capture effects of highly scattering samples.

Thermal instabilities in magnetically confined plasmas: Solar coronal loops

International Nuclear Information System (INIS)

Habbal, S.R.; Rosner, R.

1979-01-01

The thermal stability of confined solar coronal structures (''loops'') is investigated, following both normal mode and a new, global instability analysis. We demonstrate that: (a) normal mode analysis shows modes with size scales comparable to that of loops to be unstable, but to be strongly affected by the loop boundary conditions; (b) a global analysis, based upon variation of the total loop energy losses and gains, yields loop stability conditions for global modes dependent upon the coronal loop heating process, with magnetically coupled heating processes giving marginal stability. The connection between the present analysis and the minimum flux corona of Hearn is also discussed

Merginų ir jų motinų tarpusavio santykių, nepasitenkinimo kūnu ir motinų naudojamo auklėjimo stiliaus sąsajos

OpenAIRE

Tkačiova, Jekaterina

2009-01-01

Pastaraisiais metais vis daugiau susirūpinimą kelia prastėjanti merginų sveikta (Forbes ir kt., 2004), o nepasitenkinimas kūnu siejamas su neigiama fizine ir psichine sveikata bei rizikingu elgesiu (dietos naudojimas, badavimas ir kt.), kuris susijęs su valgymo sutrikimų vystimusi, žema saviverte, depresija, savęs žalojimu ir net savižudybėmis. Darbo tikslas - ištirti merginų ir jų motinų tarpusavio santykių sąsajas su nepasitenkinimu kūnu bei motinų naudojamu auklėjimo stiliumi. Tiriamųjų...

Magnetic evaluation of hydrogen pressures changes on MHD fluctuations in IR-T1 tokamak plasma

Science.gov (United States)

Alipour, Ramin; Ghanbari, Mohamad R.

2018-04-01

Identification of tokamak plasma parameters and investigation on the effects of each parameter on the plasma characteristics is important for the better understanding of magnetohydrodynamic (MHD) activities in the tokamak plasma. The effect of different hydrogen pressures of 1.9, 2.5 and 2.9 Torr on MHD fluctuations of the IR-T1 tokamak plasma was investigated by using of 12 Mirnov coils, singular value decomposition and wavelet analysis. The parameters such as plasma current, loop voltage, power spectrum density, energy percent of poloidal modes, dominant spatial structures and temporal structures of poloidal modes at different plasma pressures are plotted. The results indicate that the MHD activities at the pressure of 2.5 Torr are less than them at other pressures. It also has been shown that in the stable area of plasma and at the pressure of 2.5 Torr, the magnetic force and the force of plasma pressure are in balance with each other and the MHD activities are at their lowest level.

Feedback loop compensates for rectifier nonlinearity

Science.gov (United States)

1966-01-01

Signal processing circuit with two negative feedback loops rectifies two sinusoidal signals which are 180 degrees out of phase and produces a single full-wave rectified output signal. Each feedback loop incorporates a feedback rectifier to compensate for the nonlinearity of the circuit.

Benzene adsorption and oxidation on Ir(111)

NARCIS (Netherlands)

Weststrate, C.J.; Bakker, J.W.; Gluhoi, A.C.; Ludwig, W.; Nieuwenhuys, B.E.

2007-01-01

Adsorption, decompn. and oxidn. of benzene on Ir(1 1 1) was studied by high resoln. (synchrotron) XPS, temp. programmed desorption and LEED. Mol. adsorption of benzene on Ir(1 1 1) is obsd. between 170 K and 350 K. Above this temp. both desorption and decompn. of benzene take place. An ordered

Carrier-free 194Ir from an 194Os/194Ir generator - a new candidate for radioimmunotherapy

International Nuclear Information System (INIS)

Mirzadeh, S.; Rice, D.E.; Knapp, F.F. Jr.

1992-01-01

Iridium-194 (t 1/2 = 19.15 h) decays by beta-particle emission (E max = 2.236 MeV) and is a potential candidate for radioimmunotherapy. An important characteristic is availability of 194 Ir from decay of reactor-produced 194 Os (t 1/2 = 6y). We report the fabrication of the first 194 Os/ 194 Ir generator system using activated carbon. In addition, a novel gas thermochromatographic method was developed for the one step conversion of metallic Os to OsO 4 and subsequent separation and purification of OsO 4 . In this manner, the reactor irradiated enriched 192 Os target was converted to 194 OsO 4 , which was then converted to the K 2 OsCl 6 for generator loading. The yield and the elution profile of carrier-free 194 Ir, and 194 Os breakthrough were determined for a prototype generator which was evaluated over a 10-month period. (author)

Physiological closed-loop control in intelligent oxygen therapy: A review.

Science.gov (United States)

Sanchez-Morillo, Daniel; Olaby, Osama; Fernandez-Granero, Miguel Angel; Leon-Jimenez, Antonio

2017-07-01

Oxygen therapy has become a standard care for the treatment of patients with chronic obstructive pulmonary disease and other hypoxemic chronic lung diseases. In current systems, manually continuous adjustment of O 2 flow rate is a time-consuming task, often unsuccessful, that requires experienced staff. The primary aim of this systematic review is to collate and report on the principles, algorithms and accuracy of autonomous physiological close-loop controlled oxygen devices as well to present recommendations for future research and studies in this area. A literature search was performed on medical database MEDLINE, engineering database IEEE-Xplore and wide-raging scientific databases Scopus and Web of Science. A narrative synthesis of the results was carried out. A summary of the findings of this review suggests that when compared to the conventional manual practice, the closed-loop controllers maintain higher saturation levels, spend less time below the target saturation, and save oxygen resources. Nonetheless, despite of their potential, autonomous oxygen therapy devices are scarce in real clinical applications. Robustness of control algorithms, fail-safe mechanisms, limited reliability of sensors, usability issues and the need for standardized evaluating methods of assessing risks can be among the reasons for this lack of matureness and need to be addressed before the wide spreading of a new generation of automatic oxygen devices. Copyright © 2017 Elsevier B.V. All rights reserved.