Physiological Reactivity Moderates the Association between Parental Directing and Young Adolescent Friendship Adjustment

Science.gov (United States)

Tu, Kelly M.; Erath, Stephen A.; Pettit, Gregory S.; El-Sheikh, Mona

2014-01-01

This study examined whether the longitudinal association between parental directing of friendships (i.e., encouraging or discouraging certain friendships) and young adolescents’ friendship adjustment (i.e., friendship quality and friends’ positive characteristics) was moderated by skin conductance level reactivity (SCLR) to peer stress. Participants included 123 young adolescents (M age = 12.03 years at T1; 50% boys; 58.5% European Americans). At T1 (summer before the transition to middle school), parents reported on the extent to which they directed adolescents toward or away from certain peers, and adolescents’ SCLR was assessed during a lab-based peer evaluation task. At T1 and T2 (spring of the first year of middle school), adolescents reported on the quality of their friendships and positive peer affiliations. Controlling for T1 friendship adjustment, parental directing predicted higher friendship quality and more positive peer affiliations, but only among young adolescents with lower SCLR, which was conceptualized as a marker of under-arousal and insensitivity to stress. Results are discussed with reference to the developmental period of early adolescence and related research on interactions between parental control and child characteristics as predictors of adolescent adjustment. PMID:25365119

Impact analysis of tap switch out of step for converter transformer

Science.gov (United States)

Hong-yue, ZHANG; Zhen-hua, ZHANG; Zhang-xue, XIONG; Gao-wang, YU

2017-06-01

AC transformer load regulation is mainly used to adjust the load side voltage level, improve the quality of power supply, the voltage range is relatively narrow. In DC system, converter transformer is the core equipment of AC and DC power converter and inverter. converter transformer tap adjustment can maintain the normal operation of the converter in small angle range control, the absorption of reactive power, economic operation, valve less stress, valve damping circuit loss, AC / DC harmonic component is also smaller. In this way, the tap switch action is more frequent, and a large range of the tap switch adjustment is required. Converter transformer with a more load voltage regulation switch, the voltage regulation range of the switch is generally 20~30%, the adjustment of each file is 1%~2%. Recently it is often found that the tap switch of Converter Transformers is out of step in Converter station. In this paper, it is analyzed in detail the impact of tap switch out of step for differential protection, overexcitation protection and zero sequence over current protection. Analysis results show that: the tap switch out of step has no effect on the differential protection and the overexcitation protection including the tap switch. But the tap switch out of step has effect on zero sequence overcurrent protection of out of step star-angle converter transformer. The zero sequence overcurrent protection will trip when the tap switch out of step is greater than 3 for out of step star-angle converter transformer.

Depletion calculations of adjuster rods in Darlington

Energy Technology Data Exchange (ETDEWEB)

Arsenault, B.; Tsang, K., E-mail: benoit.arsenault@amecfw.com, E-mail: kwok.tsang@amecfw.com [AMEC Foster Wheeler, Toronto, ON (Canada)

2015-07-01

This paper describes the simulation methodology and reactivity worth calculated for aged adjuster rods in the Darlington core. ORIGEN-S IST was applied to simulate the isotope transmutation process of the stainless steel and titanium adjusters. The compositions were used in DRAGON-IST to calculate the change in incremental properties of aged adjusters. Pre-simulations of the reactivity worth of the stainless steel and titanium adjusters in Darlington were performed using RFSP-IST and the results showed that the titanium adjuster rods exhibit faster reactivity-worth drop than that of stainless steel rods. (author)

Walking velocity and step length adjustments affect knee joint contact forces in healthy weight and obese adults.

Science.gov (United States)

Milner, Clare E; Meardon, Stacey A; Hawkins, Jillian L; Willson, John D

2018-04-28

Knee osteoarthritis is a major public health problem and adults with obesity are particularly at risk. One approach to alleviating this problem is to reduce the mechanical load at the joint during daily activity. Adjusting temporospatial parameters of walking could mitigate cumulative knee joint mechanical loads. The purpose of this study was to determine how adjustments to velocity and step length affects knee joint loading in healthy weight adults and adults with obesity. We collected three-dimensional gait analysis data on 10 adults with a normal body mass index and 10 adults with obesity during over ground walking in nine different conditions. In addition to preferred velocity and step length, we also conducted combinations of 15% increased and decreased velocity and step length. Peak tibiofemoral joint impulse and knee adduction angular impulse were reduced in the decreased step length conditions in both healthy weight adults (main effect) and those with obesity (interaction effect). Peak knee joint adduction moment was also reduced with decreased step length, and with decreased velocity in both groups. We conclude from these results that adopting shorter step lengths during daily activity and when walking for exercise can reduce mechanical stimuli associated with articular cartilage degenerative processes in adults with and without obesity. Thus, walking with reduced step length may benefit adults at risk for disability due to knee osteoarthritis. Adopting a shorter step length during daily walking activity may reduce knee joint loading and thus benefit those at risk for knee cartilage degeneration. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:XX-XX, 2018. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Reactive and Proactive Subtypes of Relational and Physical Aggression in Middle Childhood: Links to Concurrent and Longitudinal Adjustment

Science.gov (United States)

Mathieson, Lindsay C.; Crick, Nicki R.

2010-01-01

Peer aggression in children is a serious issue that school psychologists often encounter on a daily basis. To develop a better understanding of aggression, it is important to look at specific subtypes of aggression and how they are related to adjustment difficulties. Past research has examined the links between reactive and proactive physical…

Effect of the selective adsorption on the reactive scattering process of molecular beams from stepped surfaces

International Nuclear Information System (INIS)

Garcia, N.

1977-01-01

An indicative proposal which may explain the diffusion of incident atomic beams scattered by a crystal surface is made in terms of the selective adsorption mechanism. In this sense, the stepped metallic surfaces present characteristics which enhance the displacements and the lifetimes of the beams on the surface. This may be important for increasing the exchange reactive scattering of molecules from crystal surfaces

Statistical modeling of tear strength for one step fixation process of reactive printing and easy care finishing

International Nuclear Information System (INIS)

Asim, F.; Mahmood, M.

2017-01-01

Statistical modeling imparts significant role in predicting the impact of potential factors affecting the one step fixation process of reactive printing and easy care finishing. Investigation of significant factors on tear strength of cotton fabric for single step fixation of reactive printing and easy care finishing has been carried out in this research work using experimental design technique. The potential design factors were; concentration of reactive dye, concentration of crease resistant, fixation method and fixation temperature. The experiments were designed using DoE (Design of Experiment) and analyzed through software Design Expert. The detailed analysis of significant factors and interactions including ANOVA (Analysis of Variance), residuals, model accuracy and statistical model for tear strength has been presented. The interaction and contour plots of vital factors has been examined. It has been found from the statistical analysis that each factor has an interaction with other factor. Most of the investigated factors showed curvature effect on other factor. After critical examination of significant plots, quadratic model of tear strength with significant terms and their interaction at alpha = 0.05 has been developed. The calculated correlation coefficient, R2 of the developed model is 0.9056. The high values of correlation coefficient inferred that developed equation of tear strength will precisely predict the tear strength over the range of values. (author)

One-step preparation of zeolite silicalite-1 microspheres with adjustable macroporosity

KAUST Repository

Hua, Jia

2009-06-23

A facile one-step method was developed for the preparation of zeolite silicalite-1 (or ZSM-5) microspheres without the need of pre-synthesizing zeolite nanocrystals. In this method, Pluronic triblock copolymer F127 was added into a homogeneous silicalite-1 synthesis solution. During the hydrothermal synthesis, zeolite nanocrystals (∼ 100 nm) were formed and spontaneously assembled into uniform micrometer-sized (3-5 μm) spheres due to the presence of F127. The obtained microspheres possess significant textual porosity (up to 0.24 cm 3/g), which can be adjusted by simply adding different amounts of styrene in the synthesis. The zeolite microspheres are useful for enzyme immobilization, and the enzyme loading is proportional to the textual porosity. © 2009 American Chemical Society.

Insect-computer hybrid legged robot with user-adjustable speed, step length and walking gait.

Science.gov (United States)

Cao, Feng; Zhang, Chao; Choo, Hao Yu; Sato, Hirotaka

2016-03-01

We have constructed an insect-computer hybrid legged robot using a living beetle (Mecynorrhina torquata; Coleoptera). The protraction/retraction and levation/depression motions in both forelegs of the beetle were elicited by electrically stimulating eight corresponding leg muscles via eight pairs of implanted electrodes. To perform a defined walking gait (e.g., gallop), different muscles were individually stimulated in a predefined sequence using a microcontroller. Different walking gaits were performed by reordering the applied stimulation signals (i.e., applying different sequences). By varying the duration of the stimulation sequences, we successfully controlled the step frequency and hence the beetle's walking speed. To the best of our knowledge, this paper presents the first demonstration of living insect locomotion control with a user-adjustable walking gait, step length and walking speed. © 2016 The Author(s).

WIMS-IST/DRAGON-IST side-step calculation of reactivity device and structural material incremental cross sections for Wolsong NPP Unit 1

International Nuclear Information System (INIS)

Dahmani, M.; McArthur, R.; Kim, B.G.; Kim, S.M.; Seo, H.-B.

2008-01-01

This paper describes the calculation of two-group incremental cross sections for all of the reactivity devices and incore structural materials for an RFSP-IST full-core model of Wolsong NPP Unit 1, in support of the conversion of the reference plant model to two energy groups. This is of particular interest since the calculation used the new standard 'side-step' approach, which is a three-dimensional supercell method that employs the Industry Standard Toolset (IST) codes DRAGON-IST and WIMS-IST with the ENDF/B-VI nuclear data library. In this technique, the macroscopic cross sections for the fuel regions and the device material specifications are first generated using the lattice code WIMS-IST with 89 energy groups. DRAGON-IST then uses this data with a standard supercell modelling approach for the three-dimensional calculations. Incremental cross sections are calculated for the stainless-steel adjuster rods (SS-ADJ), the liquid zone control units (LZCU), the shutoff rods (SOR), the mechanical control absorbers (MCA) and various structural materials, such as guide tubes, springs, locators, brackets, adjuster cables and support bars and the moderator inlet nozzle deflectors. Isotopic compositions of the Zircaloy-2, stainless steel and Inconel X-750 alloys in these items are derived from Wolsong NPP Unit 1 history dockets. Their geometrical layouts are based on applicable design drawings. Mid-burnup fuel with no moderator poison was assumed. The incremental cross sections and key aspects of the modelling are summarized in this paper. (author)

UV-enhanced reactivation of minute-virus-of-mice: stimulation of a late step in the viral life cycle

International Nuclear Information System (INIS)

Rommelaere, J.; Vos, J.-M.; Cornelis, J.J.

1981-01-01

UV-enhanced reactivation of minute-virus-of-mice (MVM), an autonomous parvovirus, was studied in parasynchronous mouse A9 cells. The survival of UV-irradiated MVM is increased in cells which have been UV-irradiated prior to infection. UV-enhanced reactivation can be explained neither by facilitated plaque detection on UV-treated indicator cells, nor by altered kinetics of virus production by UV-irradiated cells. No effect of the multiplicity of infection on virus survival was detected in unirradiated or irradiated cells. The magnitude of UV-enhanced reactivation is a direct exponential function of the UV dose administered to the virus while virus survival is inversely proportional to the UV dosage. The expression of UV-enhanced reactivation can be activated in cells arrested in G 0 , it requires de novo protein synthesis and it is maximal when cells are irradiated 30 h before the onset of viral DNA replication. Early phases of the viral cycle, such as adsorption to cellular receptors, migration to the nucleus and uncoating were not affected by cell irradiation and are unlikely targets of the UV-enhanced reactivation function(s). These results, together with the single-strandedness of the viral genome, strongly suggest that the step stimulated in UV-irradiated cells functions concomitant with, or subsequent to, viral DNA replication. (author)

Using the WIMS-DIREN bigroup and multigroup methodology for Cernavoda Unit 1 and Unit 2 adjuster rods comparative reactivity calculations at Phase B commissioning

International Nuclear Information System (INIS)

Prodea, Iosif; Patrulescu, Ilie; Rizoiu, Andrei; Danila, Nicolae; Prisecaru, Ilie

2007-01-01

One of the most important CANDU reactor regulation system is the Adjuster Rods System (ADJ). The individual and bank calibration and performance evaluation of this system is carried out during the Phase B commissioning. The ADJ rods are grouped into seven banks based on full power reactivity control requirements. The Cernavoda Unit 2 adjuster rods characteristics were designed more than twenty years ago at INR Pitesti in the end of a fruitful collaboration between INR Pitesti (as designer) and Bristol Aerospace Limited (as manufacturer). In 1996, during the Phase B commissioning tests only AECL diffusion and Westcott approximation methodology was used. An alternative integral transport and high-modes diffusion approximation methodology was developed in INR Pitesti during the last years. As a result, the first collision probability code PIJXYZ was created and developed to carry out the supercell calculations as well as the code DIREN for 3D diffusion-based core simulations. The aim of this work was to evaluate comparatively the two adjuster rods systems (from Unit 1 and 2) in commissioning conditions. The concrete results will consist of individual, bank and total adjuster rods reactivity estimations with an emphasis on the differences and similarities between them. (authors)

Coolant void reactivity adjustments in advanced CANDU lattices using adjoint sensitivity technique

International Nuclear Information System (INIS)

Assawaroongruengchot, M.; Marleau, G.

2008-01-01

Coolant void reactivity (CVR) is an important factor in reactor accident analysis. Here we study the adjustments of CVR at beginning of burnup cycle (BOC) and k eff at end of burnup cycle (EOC) for a 2D Advanced CANDU Reactor (ACR) lattice using the optimization and adjoint sensitivity techniques. The sensitivity coefficients are evaluated using the perturbation theory based on the integral neutron transport equations. The neutron and flux importance transport solutions are obtained by the method of cyclic characteristics (MOCC). Three sets of parameters for CVR-BOC and k eff -EOC adjustments are studied: (1) Dysprosium density in the central pin with Uranium enrichment in the outer fuel rings, (2) Dysprosium density and Uranium enrichment both in the central pin, and (3) the same parameters as in the first case but the objective is to obtain a negative checkerboard CVR-BOC (CBCVR-BOC). To approximate the EOC sensitivity coefficient, we perform constant-power burnup/depletion calculations using a slightly perturbed nuclear library and the unperturbed neutron fluxes to estimate the variation of nuclide densities at EOC. Our aim is to achieve a desired negative CVR-BOC of -2 mk and k eff -EOC of 0.900 for the first two cases, and a CBCVR-BOC of -2 mk and k eff -EOC of 0.900 for the last case. Sensitivity analyses of CVR and eigenvalue are also included in our study

Coolant void reactivity adjustments in advanced CANDU lattices using adjoint sensitivity technique

Energy Technology Data Exchange (ETDEWEB)

Assawaroongruengchot, M. [Institut de Genie Nucleaire, Ecole Polytechnique de Montreal, P.O. Box 6079, stn. Centre-ville, Montreal, H3C3A7 (Canada)], E-mail: monchaia@gmail.com; Marleau, G. [Institut de Genie Nucleaire, Ecole Polytechnique de Montreal, P.O. Box 6079, stn. Centre-ville, Montreal, H3C3A7 (Canada)], E-mail: guy.marleau@polymtl.ca

2008-03-15

Coolant void reactivity (CVR) is an important factor in reactor accident analysis. Here we study the adjustments of CVR at beginning of burnup cycle (BOC) and k{sub eff} at end of burnup cycle (EOC) for a 2D Advanced CANDU Reactor (ACR) lattice using the optimization and adjoint sensitivity techniques. The sensitivity coefficients are evaluated using the perturbation theory based on the integral neutron transport equations. The neutron and flux importance transport solutions are obtained by the method of cyclic characteristics (MOCC). Three sets of parameters for CVR-BOC and k{sub eff}-EOC adjustments are studied: (1) Dysprosium density in the central pin with Uranium enrichment in the outer fuel rings, (2) Dysprosium density and Uranium enrichment both in the central pin, and (3) the same parameters as in the first case but the objective is to obtain a negative checkerboard CVR-BOC (CBCVR-BOC). To approximate the EOC sensitivity coefficient, we perform constant-power burnup/depletion calculations using a slightly perturbed nuclear library and the unperturbed neutron fluxes to estimate the variation of nuclide densities at EOC. Our aim is to achieve a desired negative CVR-BOC of -2 mk and k{sub eff}-EOC of 0.900 for the first two cases, and a CBCVR-BOC of -2 mk and k{sub eff}-EOC of 0.900 for the last case. Sensitivity analyses of CVR and eigenvalue are also included in our study.

Elderly fallers enhance dynamic stability through anticipatory postural adjustments during a choice stepping reaction time

Directory of Open Access Journals (Sweden)

Romain Tisserand

2016-11-01

Full Text Available In the case of disequilibrium, the capacity to step quickly is critical to avoid falling for elderly. This capacity can be simply assessed through the choice stepping reaction time test (CSRT, where elderly fallers (F take longer to step than elderly non-fallers (NF. However, reasons why elderly F elongate their stepping time remain unclear. The purpose of this study is to assess the characteristics of anticipated postural adjustments (APA that elderly F develop in a stepping context and their consequences on the dynamic stability. 44 community-dwelling elderly subjects (20 F and 22 NF performed a CSRT where kinematics and ground reaction forces were collected. Variables were analyzed using two-way repeated measures ANOVAs. Results for F compared to NF showed that stepping time is elongated, due to a longer APA phase. During APA, they seem to use two distinct balance strategies, depending on the axis: in the anteroposterior direction, we measured a smaller backward movement and slower peak velocity of the center of pressure (CoP; in the mediolateral direction, the CoP movement was similar in amplitude and peak velocity between groups but lasted longer. The biomechanical consequence of both strategies was an increased margin of stability (MoS at foot-off, in the respective direction. By elongating their APA, elderly F use a safer balance strategy that prioritizes dynamic stability conditions instead of the objective of the task. Such a choice in balance strategy probably comes from muscular limitations and/or a higher fear of falling and paradoxically indicates an increased risk of fall.

Effects of walking speed on the step-by-step control of step width.

Science.gov (United States)

Stimpson, Katy H; Heitkamp, Lauren N; Horne, Joscelyn S; Dean, Jesse C

2018-02-08

Young, healthy adults walking at typical preferred speeds use step-by-step adjustments of step width to appropriately redirect their center of mass motion and ensure mediolateral stability. However, it is presently unclear whether this control strategy is retained when walking at the slower speeds preferred by many clinical populations. We investigated whether the typical stabilization strategy is influenced by walking speed. Twelve young, neurologically intact participants walked on a treadmill at a range of prescribed speeds (0.2-1.2 m/s). The mediolateral stabilization strategy was quantified as the proportion of step width variance predicted by the mechanical state of the pelvis throughout a step (calculated as R 2 magnitude from a multiple linear regression). Our ability to accurately predict the upcoming step width increased over the course of a step. The strength of the relationship between step width and pelvis mechanics at the start of a step was reduced at slower speeds. However, these speed-dependent differences largely disappeared by the end of a step, other than at the slowest walking speed (0.2 m/s). These results suggest that mechanics-dependent adjustments in step width are a consistent component of healthy gait across speeds and contexts. However, slower walking speeds may ease this control by allowing mediolateral repositioning of the swing leg to occur later in a step, thus encouraging slower walking among clinical populations with limited sensorimotor control. Published by Elsevier Ltd.

Minimizing Freshwater Consumption in the Wash-Off Step in Textile Reactive Dyeing by Catalytic Ozonation with Carbon Aerogel Hosted Bimetallic Catalyst

Directory of Open Access Journals (Sweden)

Enling Hu

2018-02-01

Full Text Available In textile reactive dyeing, dyed fabrics have to be rinsed in the wash-off step several times to improve colorfastness. Thus, the multiple rinsing processes drastically increase the freshwater consumption and meanwhile generate massive waste rinsing effluents. This paper addresses an innovative alternative to recycle the waste effluents to minimize freshwater consumption in the wash-off step. Accordingly, catalytic ozonation with a highly effective catalyst has been applied to remedy the waste rinsing effluents for recycling. The carbon aerogel (CA hosted bimetallic hybrid material (Ag–Fe2O3@CA was fabricated and used as the catalyst in the degradation of residual dyes in the waste rinsing effluents by ozonation treatments. The results indicate the participation of Ag–Fe2O3@CA had strikingly enhanced the removal percentage of chemical oxidation demand by 30%. In addition, it has been validated that waste effluents had been successfully reclaimed after catalytic ozonation with Ag–Fe2O3@CA. They could be additionally reused to reduce freshwater consumption in the wash-off step, but without sacrificing the color quality of corresponding fabrics in terms of color difference and colorfastness. This study may be the first to report the feasibility of catalytic ozonation in minimization of freshwater consumption in the wash-off step in textile reactive dyeing.

Theory of Work Adjustment Personality Constructs.

Science.gov (United States)

Lawson, Loralie

1993-01-01

To measure Theory of Work Adjustment personality and adjustment style dimensions, content-based scales were analyzed for homogeneity and successively reanalyzed for reliability improvement. Three sound scales were developed: inflexibility, activeness, and reactiveness. (SK)

Lateral step initiation behavior in older adults.

Science.gov (United States)

Sparto, Patrick J; Jennings, J Richard; Furman, Joseph M; Redfern, Mark S

2014-02-01

Older adults have varied postural responses during induced and voluntary lateral stepping. The purpose of the research was to quantify the occurrence of different stepping strategies during lateral step initiation in older adults and to relate the stepping responses to retrospective history of falls. Seventy community-ambulating older adults (mean age 76 y, range 70-94 y) performed voluntary lateral steps as quickly as possible to the right or left in response to a visual cue, in a blocked design. Vertical ground reaction forces were measured using a forceplate, and the number and latency of postural adjustments were quantified. Subjects were assigned to groups based on their stepping strategy. The frequency of trials with one or two postural adjustments was compared with data from 20 younger adults (mean age 38 y, range 21-58 y). Logistic regression was used to relate presence of a fall in the previous year with the number and latency of postural adjustments. In comparison with younger adults, who almost always demonstrated one postural adjustment when stepping laterally, older adults constituted a continuous distribution in the percentage of step trials made with one postural adjustment (from 0% to 100% of trials). Latencies of the initial postural adjustment and foot liftoff varied depending on the number of postural adjustments made. A history of falls was associated a larger percentage of two postural adjustments, and a longer latency of foot liftoff. In conclusion, the number and latency of postural adjustments made during voluntary lateral stepping provides additional evidence that lateral control of posture may be a critical indicator of aging. Copyright © 2013 Elsevier B.V. All rights reserved.

Biclustering of gene expression data using reactive greedy randomized adaptive search procedure.

Science.gov (United States)

Dharan, Smitha; Nair, Achuthsankar S

2009-01-30

Biclustering algorithms belong to a distinct class of clustering algorithms that perform simultaneous clustering of both rows and columns of the gene expression matrix and can be a very useful analysis tool when some genes have multiple functions and experimental conditions are diverse. Cheng and Church have introduced a measure called mean squared residue score to evaluate the quality of a bicluster and has become one of the most popular measures to search for biclusters. In this paper, we review basic concepts of the metaheuristics Greedy Randomized Adaptive Search Procedure (GRASP)-construction and local search phases and propose a new method which is a variant of GRASP called Reactive Greedy Randomized Adaptive Search Procedure (Reactive GRASP) to detect significant biclusters from large microarray datasets. The method has two major steps. First, high quality bicluster seeds are generated by means of k-means clustering. In the second step, these seeds are grown using the Reactive GRASP, in which the basic parameter that defines the restrictiveness of the candidate list is self-adjusted, depending on the quality of the solutions found previously. We performed statistical and biological validations of the biclusters obtained and evaluated the method against the results of basic GRASP and as well as with the classic work of Cheng and Church. The experimental results indicate that the Reactive GRASP approach outperforms the basic GRASP algorithm and Cheng and Church approach. The Reactive GRASP approach for the detection of significant biclusters is robust and does not require calibration efforts.

Stability of gas atomized reactive powders through multiple step in-situ passivation

Science.gov (United States)

Anderson, Iver E.; Steinmetz, Andrew D.; Byrd, David J.

2017-05-16

A method for gas atomization of oxygen-reactive reactive metals and alloys wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a protective reaction film on the atomized particles. The present invention is especially useful for making highly pyrophoric reactive metal or alloy atomized powders, such as atomized magnesium and magnesium alloy powders. The gaseous reactive species (agents) are introduced into the atomization spray chamber at locations downstream of a gas atomizing nozzle as determined by the desired powder or particle temperature for the reactions and the desired thickness of the reaction film.

Assessment of CANDU-6 reactivity devices for DUPIC fuel

International Nuclear Information System (INIS)

Jeong, Chang Joon; Choi, Hang Bok

1998-11-01

Reactivity device characteristics for a CANDU 6 reactor loaded with DUPIC fuel have been assessed. The lattice parameters were generated by WIMS-AECL code and the core calculations were performed by RFSP code with a 3-dimensional full core model. The reactivity devices studied are the zone controller, adjusters, mechanical control absorber and shutoff rods. For the zone controller system, damping capability for spatial oscillation was investigated. For the adjusters, the restart capability was investigated. For the adjusters, the restart capability was investigated. The shin operation and power stepback calculation were also performed to confirm the compatibility of the current adjuster system. The mechanical control absorber was assessed for the function of compensating temperature reactivity feedback following a power reduction. And shutoff rods were also assessed to investigate the following a power reduction. And shutoff rods were also assessed to investigate the static reactivity worth. This study has shown that the current reactivity device system of CANDU-6 core with the DUPIC fuel. (author). 9 refs., 17 tabs., 7 figs

Orifice microreactor for the production of an organic peroxide – non-reactive and reactive characterization

NARCIS (Netherlands)

Illg, T.; Hessel, V.; Löb, P.; Schouten, J.C.

2012-01-01

In this article, the transfer of a two-step, biphasic, and exothermic peroxide synthesis into a microreactor assisted process is discussed as well as the non-reactive and reactive characterization of the developed orifice microreactor. Residence time distribution measurements showed nearly ideal

A novel non-sequential hydrogen-pulsed deep reactive ion etching of silicon

International Nuclear Information System (INIS)

Gharooni, M; Mohajerzadeh, A; Sandoughsaz, A; Khanof, S; Mohajerzadeh, S; Asl-Soleimani, E

2013-01-01

A non-sequential pulsed-mode deep reactive ion etching of silicon is reported that employs continuous etching and passivation based on SF 6 and H 2 gases. The passivation layer, as an important step for deep vertical etching of silicon, is feasible by hydrogen pulses in proper time-slots. By adjusting the etching parameters such as plasma power, H 2 and SF 6 flows and hydrogen pulse timing, the process can be controlled for minimum underetch and high etch-rate at the same time. High-aspect-ratio features can be realized with low-density plasma power and by controlling the reaction chemistry. The so-called reactive ion etching lag has been minimized by operating the reactor at higher pressures. X-ray photoelectron spectroscopy and scanning electron microscopy have been used to study the formation of the passivation layer and the passivation mechanism. (paper)

Reactive power supply by distributed generators

OpenAIRE

Braun, M.

2008-01-01

Distributed reactive power supply is necessary in distribution networks for an optimized network operation. This paper presents first the reactive power supply capabilities of generators connected to the distribution network (distributed generators). In a second step an approach is proposed of determining the energy losses resulting from reactive power supply by distributed generators. The costs for compensating these losses represent the operational costs of reactive power supply. These cost...

Weigle Reactivation in Acinetobacter Calcoaceticus

DEFF Research Database (Denmark)

Berenstein, Dvora

1982-01-01

phage and host survivals of about 5 times 10-6 and 1 times 10-1, respectively. Intracellular development of W-reactivated P78 was followed by one-step growth experiments. Conditions which allowed maximal W-reactivation also extended the period of phage production and yielded a somewhat reduced burst......Weigle (W)-reactivation was demonstrated in Acinetobacter calcoaceticus for the UV-irra-diated lysogenic phage P78. The reactivation factor (survival of irradiated phage on irradiated bacteria/ survival on unirradiated bacteria) reached a maximum value of 20. This was obtained at UV-doses giving...

Hamming generalized corrector for reactivity calculation

International Nuclear Information System (INIS)

Suescun-Diaz, Daniel; Ibarguen-Gonzalez, Maria C.; Figueroa-Jimenez, Jorge H.

2014-01-01

This work presents the Hamming method generalized corrector for numerically resolving the differential equation of delayed neutron precursor concentration from the point kinetics equations for reactivity calculation, without using the nuclear power history or the Laplace transform. A study was carried out of several correctors with their respective modifiers with different time step calculations, to offer stability and greater precision. Better results are obtained for some correctors than with other existing methods. Reactivity can be calculated with precision of the order h 5 , where h is the time step. (orig.)

Treating water-reactive wastes

International Nuclear Information System (INIS)

Lussiez, G.W.

1993-01-01

Some compounds and elements, such as lithium hydride, magnesium, sodium, and calcium react violently with water to generate much heat and produce hydrogen. The hydrogen can ignite or even form an explosive mixture with air. Other metals may react rapidly only if they are finely divided. Some of the waste produced at Los Alamos National Laboratory includes these metals that are contaminated with radioactivity. By far the greatest volume of water-reactive waste is lithium hydride contaminated with depleted uranium. Reactivity of the water-reactive wastes is neutralized with an atmosphere of humid nitrogen, which prevents the formation of an explosive mixture of hydrogen and air. When we adjust the temperature of the nitrogen and the humidifier, the nitrogen can be more or less humid, and the rate of reaction can be adjusted and controlled. Los Alamos has investigated the rates of reaction of lithium hydride as a function of the temperature and humidity, and, as anticipated, they in with in temperature and humidity. Los Alamos will investigate other variables. For example, the nitrogen flow will be optimized to conserve nitrogen and yet keep the reaction rates high. Reaction rates will be determined for various forms of lithium waste, from small chips to powder. Bench work will lead to the design of a skid-mounted process for treating wastes. Other water-reactive wastes will also be investigated

Interconnection and transportation networks: adjustments and stability; Reseaux d'interconnexion et de transport: reglages et stabilite

Energy Technology Data Exchange (ETDEWEB)

Bornard, P. [Reseau de Transport d' Electricite (RTE), Div. Systeme Electrique, 92 - Paris la Defense (France); Pavard, M. [Electricite de France (EDF), 75 - Paris (France); Testud, G. [Reseau de Transport d' Electricite (RTE), Dept. Exploitation du Systeme Electrique, 92 - Paris la Defense (France)

2005-10-01

Keeping the mastery of the safety of a power transportation system and respecting the contractual commitments with respect to the network users implies the implementation of efficient frequency and voltage adjustment systems. This article presents a synthetic overview of the methods and means implemented to ensure the adjustment of the voltage and frequency and the stability of very-high voltage power transportation networks: 1 - recalls of the general problem; 2 - frequency and active power adjustment: adapting generation to consumption, adapting consumption to generation; 3 - voltage and reactive power adjustment: duality of the voltage-reactive compensation adjustment, compensation of the reactive power, voltage adjustment chain, voltage adjustment of very high voltage networks, collapse of the voltage plan; 4 - alternators stability: static stability, transient stability, numerical simulation methods, stability improvement; 5 - conclusion. (J.S.)

An autonomous organic reaction search engine for chemical reactivity

Science.gov (United States)

Dragone, Vincenza; Sans, Victor; Henson, Alon B.; Granda, Jaroslaw M.; Cronin, Leroy

2017-06-01

The exploration of chemical space for new reactivity, reactions and molecules is limited by the need for separate work-up-separation steps searching for molecules rather than reactivity. Herein we present a system that can autonomously evaluate chemical reactivity within a network of 64 possible reaction combinations and aims for new reactivity, rather than a predefined set of targets. The robotic system combines chemical handling, in-line spectroscopy and real-time feedback and analysis with an algorithm that is able to distinguish and select the most reactive pathways, generating a reaction selection index (RSI) without need for separate work-up or purification steps. This allows the automatic navigation of a chemical network, leading to previously unreported molecules while needing only to do a fraction of the total possible reactions without any prior knowledge of the chemistry. We show the RSI correlates with reactivity and is able to search chemical space using the most reactive pathways.

Comparing the efficacy of metronome beeps and stepping stones to adjust gait: Steps to follow!

NARCIS (Netherlands)

Bank, P.J.M.; Roerdink, M.; Peper, C.E.

2011-01-01

Acoustic metronomes and visual targets have been used in rehabilitation practice to improve pathological gait. In addition, they may be instrumental in evaluating and training instantaneous gait adjustments. The aim of this study was to compare the efficacy of two cue types in inducing gait

Steps in the construction and verification of an explanatory model of psychosocial adjustment

Directory of Open Access Journals (Sweden)

Arantzazu Rodríguez-Fernández

2016-06-01

Full Text Available The aim of the present study was to empirically test an explanatory model of psychosocial adjustment during adolescence, with psychosocial adjustment during this stage being understood as a combination of school adjustment (or school engagement and subjective well-being. According to the hypothetic model, psychosocial adjustment depends on self-concept and resilience, which in turn act as mediators of the influence of perceived social support (from family, peers and teachers on this adjustment. Participants were 1250 secondary school students (638 girls and 612 boys aged between 12 and 15 years (Mean = 13.72; SD = 1.09. The results provided evidence of: (a the influence of all three types of perceived support on subject resilience and self-concept, with perceived family support being particularly important in this respect; (b the influence of the support received from teachers on school adjustment and support received from the family on psychological wellbeing; and (c the absence of any direct influence of peer support on psychosocial adjustment, although indirect influence was observed through the psychological variables studied. These results are discussed from an educational perspective and in terms of future research.

Steps in the construction and verification of an explanatory model of psychosocial adjustment

Directory of Open Access Journals (Sweden)

Arantzazu Rodríguez-Fernández

2016-06-01

Full Text Available The aim of the present study was to empirically test an explanatory model of psychosocial adjustment during adolescence, with psychosocial adjustment during this stage being understood as a combination of school adjustment (or school engagement and subjective well-being. According to the hypothetic model, psychosocial adjustment depends on self-concept and resilience, which in turn act as mediators of the influence of perceived social support (from family, peers and teachers on this adjustment. Participants were 1250 secondary school students (638 girls and 612 boys aged between 12 and 15 years (Mean = 13.72; SD = 1.09. The results provided evidence of: (a the influence of all three types of perceived support on subject resilience and self-concept, with perceived family support being particularly important in this respect; (b the influence of the support received from teachers on school adjustment and support received from the family on psychological wellbeing; and (c the absence of any direct influence of peer support on psychosocial adjustment, although indirect influence was observed through the psychological variables studied. These results are discussed from an educational perspective and in terms of future research

Assessment of reactivity devices for CANDU-6 with DUPIC fuel

International Nuclear Information System (INIS)

Jeong, Chang Joon; Choi, Hang Bok

1998-01-01

Reactivity device characteristics for a CANDU-6 reactor loaded with DUPIC fuel have been assessed. A transport code WIMS-AECL and a three-dimensional diffusion code RFSP were used for the lattice parameter generation and the core calculation, respectively. Three major reactivity devices have been assessed for their inherent functions. For the zone controller system, damping capability for spatial oscillation was investigated. The restart capability of the adjuster system was investigated. The shim operation and power stepback calculation were also performed to confirm the compatibility of the current adjuster rod system. The mechanical control absorber was assessed for the capability to compensate the temperature reactivity feedback following a power reduction. This study has shown that the current reactivity device systems retain their functions when used in a DUPIC fuel CANDU reactor

A Method of Dynamic Extended Reactive Power Optimization in Distribution Network Containing Photovoltaic-Storage System

Science.gov (United States)

Wang, Wu; Huang, Wei; Zhang, Yongjun

2018-03-01

The grid-integration of Photovoltaic-Storage System brings some undefined factors to the network. In order to make full use of the adjusting ability of Photovoltaic-Storage System (PSS), this paper puts forward a reactive power optimization model, which are used to construct the objective function based on power loss and the device adjusting cost, including energy storage adjusting cost. By using Cataclysmic Genetic Algorithm to solve this optimization problem, and comparing with other optimization method, the result proved that: the method of dynamic extended reactive power optimization this article puts forward, can enhance the effect of reactive power optimization, including reducing power loss and device adjusting cost, meanwhile, it gives consideration to the safety of voltage.

The Persian Version of Fertility Adjustment Scale: Psychometric Properties

Directory of Open Access Journals (Sweden)

Asma Tiyuri

2018-05-01

Full Text Available Background Infertility is a common clinical problem. Psychological adjustment to infertility refers to changing the viewpoint and attitude of an infertile person toward infertility problems, treatments and possible outcomes. The present study aims to prepare a valid and reliable scale for assessing the psychological adjustment to infertility, by determining the cultural adaptation, validity and reliability of the Persian version of the Fertility Adjustment Scale. Materials and Methods This is a cross-sectional study performed to localize and validate the Fertility Adjustment Scale, in which 40 infertile women and 40 healthy subjects (fertile or having children were detected by a gynecolo- gist and the subjects who completed the Fertility Adjustment Scale (FAS questionnaire were recruited. This study had four steps: in the first step, the literature was reviewed, in the second step, the scale was translated, in the third step, the content and construct validity indicators were calculated, and in the fourth step, reliability of the scale was validated. Results The mean (± SE and range of fertility adjustment total scores in the infertile group and the control group were 43.2 (1.2 and 27-57 and 42.3 (1.5 and 18-57, respectively (P=0.623. The content validity was good according to Con- tent Validity Index score (0.7-0.8. A two-component structure was extracted from factor analysis which approximately justifies 52.0% of the cumulative variations. A Cronbach’s alpha value of 0.68 showed moderate reliability. Conclusion The results of this study revealed that the infertility adjustment scale is a useful tool for the analysis of psy- chological reactions towards infertility problems and evaluation of the consequences of treating this social-clinical problem.

Development of Stepping Endurance Test Plan on CRDM of a Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, DongHyun; Kim, Hyeonil; Park, Suki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Various types of the irradiation targets can be loaded and unloaded during power operation, according to the purpose of research reactor utilization. And their reactivity worth varies as well. The insertion rate of reactivity is dependent to reactivity worth of targets, travel length during loading or unloading and transfer device speed. Due to the reactivity transition during loading and unloading, neutron power is changed and reaches an action point of the reactor regulating system. Based on the measured neutron rate of change, reactor power control system controls the power with its own algorithm. It generates the signals and transmits these to the CRDM for motor driving. Stepping motors on the CRDM move the control rods with step signals. The process repeats until power is stabilized. Accordingly, the stepping behaviours of CRDM should be modelled upon an understanding of the control process and reactor responses. Methodology for a stepping endurance test plan on the CRDM of a research reactor is developed since CRDM endurance is very important for reactor controller and should be ensured for a certain period of time throughout the life of a research reactor. Therefore, it is expected to provide a reasonable stepping test plan. In the future, the simulation will be performed with specific design values.

Design of reactive power procurement in deregulated electricity market

African Journals Online (AJOL)

user

novel reactive power procurement model is proposed, which ensure secure and ..... The simulation is performed in the Matlab. .... focus of this paper is a reactive procurement market model, which is a basically two-step optimization process.

Accessory stimulus modulates executive function during stepping task.

Science.gov (United States)

Watanabe, Tatsunori; Koyama, Soichiro; Tanabe, Shigeo; Nojima, Ippei

2015-07-01

When multiple sensory modalities are simultaneously presented, reaction time can be reduced while interference enlarges. The purpose of this research was to examine the effects of task-irrelevant acoustic accessory stimuli simultaneously presented with visual imperative stimuli on executive function during stepping. Executive functions were assessed by analyzing temporal events and errors in the initial weight transfer of the postural responses prior to a step (anticipatory postural adjustment errors). Eleven healthy young adults stepped forward in response to a visual stimulus. We applied a choice reaction time task and the Simon task, which consisted of congruent and incongruent conditions. Accessory stimuli were randomly presented with the visual stimuli. Compared with trials without accessory stimuli, the anticipatory postural adjustment error rates were higher in trials with accessory stimuli in the incongruent condition and the reaction times were shorter in trials with accessory stimuli in all the task conditions. Analyses after division of trials according to whether anticipatory postural adjustment error occurred or not revealed that the reaction times of trials with anticipatory postural adjustment errors were reduced more than those of trials without anticipatory postural adjustment errors in the incongruent condition. These results suggest that accessory stimuli modulate the initial motor programming of stepping by lowering decision threshold and exclusively under spatial incompatibility facilitate automatic response activation. The present findings advance the knowledge of intersensory judgment processes during stepping and may aid in the development of intervention and evaluation tools for individuals at risk of falls. Copyright © 2015 the American Physiological Society.

Adjustment errors of sunstones in the first step of sky-polarimetric Viking navigation: studies with dichroic cordierite/ tourmaline and birefringent calcite crystals.

Science.gov (United States)

Száz, Dénes; Farkas, Alexandra; Blahó, Miklós; Barta, András; Egri, Ádám; Kretzer, Balázs; Hegedüs, Tibor; Jäger, Zoltán; Horváth, Gábor

2016-01-01

According to an old but still unproven theory, Viking navigators analysed the skylight polarization with dichroic cordierite or tourmaline, or birefringent calcite sunstones in cloudy/foggy weather. Combining these sunstones with their sun-dial, they could determine the position of the occluded sun, from which the geographical northern direction could be guessed. In psychophysical laboratory experiments, we studied the accuracy of the first step of this sky-polarimetric Viking navigation. We measured the adjustment error e of rotatable cordierite, tourmaline and calcite crystals when the task was to determine the direction of polarization of white light as a function of the degree of linear polarization p. From the obtained error functions e(p), the thresholds p* above which the first step can still function (i.e. when the intensity change seen through the rotating analyser can be sensed) were derived. Cordierite is about twice as reliable as tourmaline. Calcite sunstones have smaller adjustment errors if the navigator looks for that orientation of the crystal where the intensity difference between the two spots seen in the crystal is maximal, rather than minimal. For higher p (greater than p crit) of incident light, the adjustment errors of calcite are larger than those of the dichroic cordierite (p crit=20%) and tourmaline (p crit=45%), while for lower p (less than p crit) calcite usually has lower adjustment errors than dichroic sunstones. We showed that real calcite crystals are not as ideal sunstones as it was believed earlier, because they usually contain scratches, impurities and crystal defects which increase considerably their adjustment errors. Thus, cordierite and tourmaline can also be at least as good sunstones as calcite. Using the psychophysical e(p) functions and the patterns of the degree of skylight polarization measured by full-sky imaging polarimetry, we computed how accurately the northern direction can be determined with the use of the Viking

A robust and powerful two-step testing procedure for local ancestry adjusted allelic association analysis in admixed populations.

Science.gov (United States)

Duan, Qing; Xu, Zheng; Raffield, Laura M; Chang, Suhua; Wu, Di; Lange, Ethan M; Reiner, Alex P; Li, Yun

2018-04-01

Genetic association studies in admixed populations allow us to gain deeper understanding of the genetic architecture of human diseases and traits. However, population stratification, complicated linkage disequilibrium (LD) patterns, and the complex interplay of allelic and ancestry effects on phenotypic traits pose challenges in such analyses. These issues may lead to detecting spurious associations and/or result in reduced statistical power. Fortunately, if handled appropriately, these same challenges provide unique opportunities for gene mapping. To address these challenges and to take these opportunities, we propose a robust and powerful two-step testing procedure Local Ancestry Adjusted Allelic (LAAA) association. In the first step, LAAA robustly captures associations due to allelic effect, ancestry effect, and interaction effect, allowing detection of effect heterogeneity across ancestral populations. In the second step, LAAA identifies the source of association, namely allelic, ancestry, or the combination. By jointly modeling allele, local ancestry, and ancestry-specific allelic effects, LAAA is highly powerful in capturing the presence of interaction between ancestry and allele effect. We evaluated the validity and statistical power of LAAA through simulations over a broad spectrum of scenarios. We further illustrated its usefulness by application to the Candidate Gene Association Resource (CARe) African American participants for association with hemoglobin levels. We were able to replicate independent groups' previously identified loci that would have been missed in CARe without joint testing. Moreover, the loci, for which LAAA detected potential effect heterogeneity, were replicated among African Americans from the Women's Health Initiative study. LAAA is freely available at https://yunliweb.its.unc.edu/LAAA. © 2017 WILEY PERIODICALS, INC.

REDSHANK I and GREENSHANK I (comprehensive point reactivity programmes for liquid moderated UO2 lattices)

International Nuclear Information System (INIS)

Alpiar, R.A.

1963-08-01

A recently issued programme (SANDPIPER I) enables few group diffusion parameters and reactivities to be derived for liquid moderated UO 2 lattices. The present programmes investigate the life history of such lattices. Burn up equations recalculate the fuel isotopic composition, in a series of steps. At each step, new few group constants and reactivity are recalculated for the new fuel composition. In addition, at each step, the control required to keep the reactivity of the reactor within a given deadband is recalculated. This control is effected by control rod withdrawal in Redshank, and by heavy water spectrum shift in Greenshank. The programme continues until the reactivity of the uncontrolled reactor falls below the deadband. (author)

Development of the adjusted nuclear cross-section library based on JENDL-3.2 for large FBR

International Nuclear Information System (INIS)

Yokoyama, Kenji; Ishikawa, Makoto; Numata, Kazuyuki

1999-04-01

JNC (and PNC) had developed the adjusted nuclear cross-section library in which the results of the JUPITER experiments were reflected. Using this adjusted library, the distinct improvement of the accuracy in nuclear design of FBR cores had been achieved. As a recent research, JNC develops a database of other integral data in addition to the JUPITER experiments, aiming at further improvement for accuracy and reliability. In 1991, the adjusted library based on JENDL-2, JFS-3-J2 (ADJ91R), was developed, and it has been used on the design research for FBR. As an evaluated nuclear library, however, JENDL-3.2 is recently used. Therefore, the authors developed an adjusted library based on JENDL-3.2 which is called JFS-3-J3.2(ADJ98). It is known that the adjusted library based on JENDL-2 overestimated the sodium void reactivity worth by 10-20%. It is expected that the adjusted library based on JENDL-3.2 solve the problem. The adjusted library JFS-3-J3.2(ADJ98) was produced with the same method as the adjusted library JFS-3-J2(ADJ91R) and used more integral parameters of JUPITER experiments than the adjusted library JFS-3-J2(ADJ91R). This report also describes the design accuracy estimation on a 600 MWe class FBR with the adjusted library JFS-3-J3.2(ADJ98). Its main nuclear design parameters (multiplication factor, burn-up reactivity loss, breeding ratio, etc.) except the sodium void reactivity worth which are calculated with the adjusted library JFS-3-J3.2(ADJ98) are almost the same as those predicted with JFS-3-J2(ADJ91R). As for the sodium void reactivity, the adjusted library JFS-3-J3.2(ADJ98) estimates about 4% smaller than the JFS-3-J2(ADJ91R) because of the change of the basic nuclear library from JENDL-2 to JENDL-3.2. (author)

Hamming method for solving the delayed neutron precursor concentration for reactivity calculation

International Nuclear Information System (INIS)

Díaz, Daniel Suescún; Ospina, Juan Felipe Flórez; Sarasty, Jesús Andrés Rodríguez

2012-01-01

Highlights: ► We present a new formulation to calculate the reactivity using the Hamming method. ► This method shows better accuracy than existing methods for reactivity calculation. ► The reactivity is calculated without limitation of the nuclear power form. ► The method can be implemented in reactivity meters with time step of up to 0.1 s. - Abstract: We propose a new method for numerically solving the inverse point kinetic equation for a nuclear reactor using the Hamming method, without requiring the nuclear power history and without using the Laplace transform. This new method converges with accuracy of order h 5 , where h is the step in the computation time. The procedure is validated for different forms of the nuclear power and with different time steps. The results indicate that this method has a better accuracy and lower computational effort compared with other conventional methods that use the nuclear power history.

Step-wise refolding of recombinant proteins.

Science.gov (United States)

Tsumoto, Kouhei; Arakawa, Tsutomu; Chen, Linda

2010-04-01

Protein refolding is still on trial-and-error basis. Here we describe step-wise dialysis refolding, in which denaturant concentration is altered in step-wise fashion. This technology controls the folding pathway by adjusting the concentrations of the denaturant and other solvent additives to induce sequential folding or disulfide formation.

An efficient unstructured WENO method for supersonic reactive flows

Science.gov (United States)

Zhao, Wen-Geng; Zheng, Hong-Wei; Liu, Feng-Jun; Shi, Xiao-Tian; Gao, Jun; Hu, Ning; Lv, Meng; Chen, Si-Cong; Zhao, Hong-Da

2018-03-01

An efficient high-order numerical method for supersonic reactive flows is proposed in this article. The reactive source term and convection term are solved separately by splitting scheme. In the reaction step, an adaptive time-step method is presented, which can improve the efficiency greatly. In the convection step, a third-order accurate weighted essentially non-oscillatory (WENO) method is adopted to reconstruct the solution in the unstructured grids. Numerical results show that our new method can capture the correct propagation speed of the detonation wave exactly even in coarse grids, while high order accuracy can be achieved in the smooth region. In addition, the proposed adaptive splitting method can reduce the computational cost greatly compared with the traditional splitting method.

REDSHANK I and GREENSHANK I (comprehensive point reactivity programmes for liquid moderated UO{sub 2} lattices)

Energy Technology Data Exchange (ETDEWEB)

Alpiar, R A [Technical Assessments and Services Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1963-08-15

A recently issued programme (SANDPIPER I) enables few group diffusion parameters and reactivities to be derived for liquid moderated UO{sub 2} lattices. The present programmes investigate the life history of such lattices. Burn up equations recalculate the fuel isotopic composition, in a series of steps. At each step, new few group constants and reactivity are recalculated for the new fuel composition. In addition, at each step, the control required to keep the reactivity of the reactor within a given deadband is recalculated. This control is effected by control rod withdrawal in Redshank, and by heavy water spectrum shift in Greenshank. The programme continues until the reactivity of the uncontrolled reactor falls below the deadband. (author)

Is impaired control of reactive stepping related to falls during inpatient stroke rehabilitation?

Science.gov (United States)

Mansfield, Avril; Inness, Elizabeth L; Wong, Jennifer S; Fraser, Julia E; McIlroy, William E

2013-01-01

Individuals with stroke fall more often than age-matched controls. Although many focus on the multifactorial nature of falls, the fundamental problem is likely the ability for an individual to generate reactions to recover from a loss of balance. Stepping reactions to recover balance are particularly important to balance recovery, and individuals with stroke have difficulty executing these responses to prevent a fall following a loss of balance. The purpose of this study is to determine if characteristics of balance recovery steps are related to falls during inpatient stroke rehabilitation. We conducted a retrospective review of individuals with stroke attending inpatient rehabilitation (n = 136). Details of falls experienced during inpatient rehabilitation were obtained from incident reports, nursing notes, and patient interviews. Stepping reactions were evoked using a "release-from-lean" postural perturbation. Poisson regression was used to determine characteristics of stepping reactions that were related to increased fall frequency relative to length of stay. In all, 20 individuals experienced 29 falls during inpatient rehabilitation. The characteristics of stepping reactions significantly related to increased fall rates were increased frequency of external assistance to prevent a fall to the floor, increased frequency of no-step responses, increased frequency of step responses with inadequate foot clearance, and delayed time to initiate stepping responses. Impaired control of balance recovery steps is related to increased fall rates during inpatient stroke rehabilitation. This study informs the specific features of stepping reactions that can be targeted with physiotherapy intervention during inpatient rehabilitation to improve dynamic stability control and potentially prevent falls.

Reduced step edges on rutile TiO (110) as competing defects to oxygen vacancies on the terraces and reactive sites for ethanol dissociation

DEFF Research Database (Denmark)

Martinez, U.; Hansen, Jonas Ørbæk; Salazar, Estephania Lira

2012-01-01

microscopy studies, we here present experimental evidence for the existence of O vacancies along the ⟨11̅ 1⟩R step edges (OS vac.’s) on rutile TiO2(110). Both the distribution of bridging O vacancies on the terraces and temperature-programed reaction experiments of ethanol-covered TiO2(110) point...... to the existence of the OS vac.’s. Based on experiments and density functional theory calculations, we show that OS vac.’s are reactive sites for ethanol dissociation via O-H bond scission. Implications of these findings are discussed...

18 CFR 154.403 - Periodic rate adjustments.

Science.gov (United States)

2010-04-01

... recovered or returned in a future surcharge. Include a step-by-step explanation of the methodology used to... terms and conditions of its tariff, the methodology and timing of any adjustments. The following must be... D of this part, the methodology must be consistent with the methodology used in the proceeding under...

Compensatory stepping responses in individuals with stroke: a pilot study.

Science.gov (United States)

Lakhani, Bimal; Mansfield, Avril; Inness, Elizabeth L; McIlroy, William E

2011-05-01

Impaired postural control and a high incidence of falls are commonly observed following stroke. Compensatory stepping responses are critical to reactive balance control. We hypothesize that, following a stroke, individuals with unilateral limb dyscontrol will be faced with the unique challenge of controlling such rapid stepping reactions that may eventually be linked to the high rate of falling. The objectives of this exploratory pilot study were to investigate compensatory stepping in individuals poststroke with regard to: (1) choice of initial stepping limb (paretic or non-paretic); (2) step characteristics; and (3) differences in step characteristics when the initial step is taken with the paretic vs. the non-paretic limb. Four subjects following stroke (38-165 days post) and 11 healthy young adults were recruited. Anterior and posterior perturbations were delivered by using a weight drop system. Force plates recorded centre-of-pressure excursion prior to the onset of stepping and step timing. Of the four subjects, three only attempted to step with their non-paretic limb and one stepped with either limb. Time to foot-off was generally slow, whereas step onset time and swing time were comparable to healthy controls. Two of the four subjects executed multistep responses in every trial, and attempts to force stepping with the paretic limb were unsuccessful in three of the four subjects. Despite high clinical balance scores, these individuals with stroke demonstrated impaired compensatory stepping responses, suggesting that current clinical evaluations might not accurately reflect reactive balance control in this population.

A stochastic framework for clearing of reactive power market

International Nuclear Information System (INIS)

Amjady, N.; Rabiee, A.; Shayanfar, H.A.

2010-01-01

This paper presents a new stochastic framework for clearing of day-ahead reactive power market. The uncertainty of generating units in the form of system contingencies are considered in the reactive power market-clearing procedure by the stochastic model in two steps. The Monte-Carlo Simulation (MCS) is first used to generate random scenarios. Then, in the second step, the stochastic market-clearing procedure is implemented as a series of deterministic optimization problems (scenarios) including non-contingent scenario and different post-contingency states. In each of these deterministic optimization problems, the objective function is total payment function (TPF) of generators which refers to the payment paid to the generators for their reactive power compensation. The effectiveness of the proposed model is examined based on the IEEE 24-bus Reliability Test System (IEEE 24-bus RTS). (author)

Do characteristics of a stationary obstacle lead to adjustments in obstacle stepping strategies?

Science.gov (United States)

Worden, Timothy A; De Jong, Audrey F; Vallis, Lori Ann

2016-01-01

Navigating cluttered and complex environments increases the risk of falling. To decrease this risk, it is important to understand the influence of obstacle visual cues on stepping parameters, however the specific obstacle characteristics that have the greatest influence on avoidance strategies is still under debate. The purpose of the current work is to provide further insight on the relationship between obstacle appearance in the environment and modulation of stepping parameters. Healthy young adults (N=8) first stepped over an obstacle with one visible top edge ("floating"; 8 trials) followed by trials where experimenters randomly altered the location of a ground reference object to one of 7 different positions (8 trials per location), which ranged from 6cm in front of, directly under, or up to 6cm behind the floating obstacle (at 2cm intervals). Mean take-off and landing distance as well as minimum foot clearance values were unchanged across different positions of the ground reference object; a consistent stepping trajectory was observed for all experimental conditions. Contrary to our hypotheses, results of this study indicate that ground based visual cues are not essential for the planning of stepping and clearance strategies. The simultaneous presentation of both floating and ground based objects may have provided critical information that lead to the adoption of a consistent strategy for clearing the top edge of the obstacle. The invariant foot placement observed here may be an appropriate stepping strategy for young adults, however this may not be the case across the lifespan or in special populations. Copyright © 2015 Elsevier B.V. All rights reserved.

Thermochemical reactivity of 5–15 mol% Fe, Co, Ni, Mn-doped cerium oxides in two-step water-splitting cycle for solar hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Gokon, Nobuyuki, E-mail: ngokon@eng.niigata-u.ac.jp [Center for Transdisciplinary Research, Niigata University, 8050 Ikarashi 2-nocho, Nishi-ku, Niigata 950-2181 (Japan); Suda, Toshinori [Graduate School of Science and Technology, Niigata University, 8050 Ikarashi 2-nocho, Niigata 950-2181 (Japan); Kodama, Tatsuya [Department of Chemistry & Chemical Engineering, Faculty of Engineering, Niigata University, 8050 Ikarashi 2-nocho, Niigata 950-2181 (Japan)

2015-10-10

Highlights: • 5–15 mol% M-doped ceria are examined for thermochemical two-step water-splitting. • 5 mol% Fe- and Co-doped ceria have stoichiometric production of oxygen and hydrogen. • 10–15 mol% Fe- and Mn-doped ceria showed near-stoichiometric production. - Abstract: The thermochemical two-step water-splitting cycle using transition element-doped cerium oxide (M–CeO{sub 2−δ}; M = Fe, Co, Ni, Mn) powders was studied for hydrogen production from water. The oxygen/hydrogen productivity and repeatability of M–CeO{sub 2−δ} materials with M doping contents in the 5–15 mol% range were examined using a thermal reduction (TR) temperature of 1500 °C and water decomposition (WD) temperatures in the 800–1150 °C range. The temperature, steam partial pressure, and steam flow rate in the WD step had an impact on the hydrogen productivity and production rate. 5 mol% Fe- and Co-doped CeO{sub 2−δ} enhances hydrogen productivity by up to 25% on average compared to undoped CeO{sub 2}, and shows stable repeatability of stoichiometric oxygen and hydrogen production for the cyclic thermochemical two-step water-splitting reaction. In addition, 5 mol% Mn-doped CeO{sub 2−δ}, 10 and 15 mol% Fe- and Mn-doped CeO{sub 2−δ} show near stoichiometric reactivities.

Development of the Calibrator of Reactivity Meter Using PC-Based DAQ System

International Nuclear Information System (INIS)

Edison; Mariatmo, A.; Sujarwono

2007-01-01

The reactivity meter calibrator has been developed by applying the PC-Based DAQ System programmed using LabVIEW. The Output of the calibrator is voltage proportional to neutron density n(t) corresponding to the step reactivity change ρ 0 . The “Kalibrator meter reactivitas.vi” program calculates seven roots and coefficients of solution n(t) of Reactor Kinetic equation using the in-hour equation. Based on data of dt = t k+1 - t k and t 0 = 0 input by user, the program approximates n(t) for each time interval t k ≤ t k+1 , where k = 0, 1, 2, 3, .... by a step function n(t) = n 0 ∑ j=1 7 A j e ω j t k . Then the program commands the DAQ device to output voltage V(t) = n(t) Volt at time t. The measurement of standard reactivity with the meter reactivity showed that the maximum deviation of measured reactivity from its standard were less than 1 %. (author)

Multi-step prediction for influenza outbreak by an adjusted long short-term memory.

Science.gov (United States)

Zhang, J; Nawata, K

2018-05-01

Influenza results in approximately 3-5 million annual cases of severe illness and 250 000-500 000 deaths. We urgently need an accurate multi-step-ahead time-series forecasting model to help hospitals to perform dynamical assignments of beds to influenza patients for the annually varied influenza season, and aid pharmaceutical companies to formulate a flexible plan of manufacturing vaccine for the yearly different influenza vaccine. In this study, we utilised four different multi-step prediction algorithms in the long short-term memory (LSTM). The result showed that implementing multiple single-output prediction in a six-layer LSTM structure achieved the best accuracy. The mean absolute percentage errors from two- to 13-step-ahead prediction for the US influenza-like illness rates were all LSTM has been applied and refined to perform multi-step-ahead prediction for influenza outbreaks. Hopefully, this modelling methodology can be applied in other countries and therefore help prevent and control influenza worldwide.

Substation Reactive Power Regulation Strategy

Science.gov (United States)

Zhang, Junfeng; Zhang, Chunwang; Ma, Daqing

2018-01-01

With the increasing requirements on the power supply quality and reliability of distribution network, voltage and reactive power regulation of substations has become one of the indispensable ways to ensure voltage quality and reactive power balance and to improve the economy and reliability of distribution network. Therefore, it is a general concern of the current power workers and operators that what kind of flexible and effective control method should be used to adjust the on-load tap-changer (OLTC) transformer and shunt compensation capacitor in a substation to achieve reactive power balance in situ, improve voltage pass rate, increase power factor and reduce active power loss. In this paper, based on the traditional nine-zone diagram and combining with the characteristics of substation, a fuzzy variable-center nine-zone diagram control method is proposed and used to make a comprehensive regulation of substation voltage and reactive power. Through the calculation and simulation of the example, this method is proved to have satisfactorily reconciled the contradiction between reactive power and voltage in real-time control and achieved the basic goal of real-time control of the substation, providing a reference value to the practical application of the substation real-time control method.

Higher sleep reactivity and insomnia mutually aggravate depressive symptoms: a cross-sectional epidemiological study in Japan.

Science.gov (United States)

Nakajima, Shun; Komada, Yoko; Sasai-Sakuma, Taeko; Okajima, Isa; Harada, Yutaka; Watanabe, Kazue; Inoue, Yuichi

2017-05-01

Sleep reactivity assessed using the Ford Insomnia Response to Stress Test (FIRST) is associated with depression. This study clarified stress reactivity and insomnia effects on depressive symptoms. A cross-sectional questionnaire survey was administered to 2645 participating government employees (35.4% female, mean age 42.8 years) during health checks conducted at Tottori prefecture, Japan, in June 2012. Questionnaire items included: demographic information; the FIRST; the Pittsburgh Sleep Quality Index (PSQI); and a 12-item version of the Center for Epidemiological Studies Depression scale (CES-D). The study defined CES-D scores of ≥12 points as positive for depression, PSQI scores of ≥5.5 points as positive for insomnia symptoms, and FIRST scores of ≥19 points as indicating higher sleep reactivity. Multivariate logistic regression analysis revealed insomnia (adjusted OR = 3.40), higher sleep reactivity (adjusted OR = 1.78), presence of disease currently being treated (adjusted OR = 1.84), and being female (adjusted OR = 1.53) as independently associated with depression. Participants with insomnia and a high FIRST score showed higher CES-D scores than those with insomnia alone and those with high FIRST without insomnia (all p insomnia. Elevated sleep reactivity and insomnia symptoms are thought to aggravate depressive symptoms. Copyright © 2017 Elsevier B.V. All rights reserved.

Calculation of reactivity without Lagrange interpolation

International Nuclear Information System (INIS)

Suescun D, D.; Figueroa J, J. H.; Rodriguez R, K. C.; Villada P, J. P.

2015-09-01

A new method to solve numerically the inverse equation of punctual kinetics without using Lagrange interpolating polynomial is formulated; this method uses a polynomial approximation with N points based on a process of recurrence for simulating different forms of nuclear power. The results show a reliable accuracy. Furthermore, the method proposed here is suitable for real-time measurements of reactivity, with step sizes of calculations greater that Δt = 0.3 s; due to its precision can be used to implement a digital meter of reactivity in real time. (Author)

Salary adjustments

CERN Multimedia

HR Department

2008-01-01

In accordance with decisions taken by the Finance Committee and Council in December 2007, salaries are adjusted with effect from 1 January 2008. Scale of basic salaries and scale of stipends paid to fellows (Annex R A 5 and R A 6 respectively): increased by 0.71% with effect from 1 January 2008. As a result of the stability of the Geneva consumer price index, following elements do not increase: a) Family Allowance, Child Allowance and Infant Allowance (Annex R A 3). b) Reimbursement of education fees: maximum amounts of reimbursement (Annex R A 4.01) for the academic year 2007/2008. Related adjustments will be implemented, wherever applicable, to Paid Associates and Students. As in the past, the actual percentage increase of each salary position may vary, due to the application of a constant step value and the rounding effects. Human Resources Department Tel. 73566

Salary adjustments

CERN Multimedia

HR Department

2008-01-01

In accordance with decisions taken by the Finance Committee and Council in December 2007, salaries are adjusted with effect from 1 January 2008. Scale of basic salaries and scale of stipends paid to fellows (Annex R A 5 and R A 6 respectively): increased by 0.71% with effect from 1 January 2008. As a result of the stability of the Geneva consumer price index, the following elements do not increase: a)\tFamily Allowance, Child Allowance and Infant Allowance (Annex R A 3); b)\tReimbursement of education fees: maximum amounts of reimbursement (Annex R A 4.01) for the academic year 2007/2008. Related adjustments will be applied, wherever applicable, to Paid Associates and Students. As in the past, the actual percentage increase of each salary position may vary, due to the application of a constant step value and rounding effects. Human Resources Department Tel. 73566

Automatized Assessment of Protective Group Reactivity: A Step Toward Big Reaction Data Analysis.

Science.gov (United States)

Lin, Arkadii I; Madzhidov, Timur I; Klimchuk, Olga; Nugmanov, Ramil I; Antipin, Igor S; Varnek, Alexandre

2016-11-28

We report a new method to assess protective groups (PGs) reactivity as a function of reaction conditions (catalyst, solvent) using raw reaction data. It is based on an intuitive similarity principle for chemical reactions: similar reactions proceed under similar conditions. Technically, reaction similarity can be assessed using the Condensed Graph of Reaction (CGR) approach representing an ensemble of reactants and products as a single molecular graph, i.e., as a pseudomolecule for which molecular descriptors or fingerprints can be calculated. CGR-based in-house tools were used to process data for 142,111 catalytic hydrogenation reactions extracted from the Reaxys database. Our results reveal some contradictions with famous Greene's Reactivity Charts based on manual expert analysis. Models developed in this study show high accuracy (ca. 90%) for predicting optimal experimental conditions of protective group deprotection.

Assessing the reactivation efficacy of hydroxylamine anion towards VX-inhibited AChE: a computational study.

Science.gov (United States)

Khan, Md Abdul Shafeeuulla; Ganguly, Bishwajit

2012-05-01

Oximate anions are used as potential reactivating agents for OP-inhibited AChE because of they possess enhanced nucleophilic reactivity due to the α-effect. We have demonstrated the process of reactivating the VX-AChE adduct with formoximate and hydroxylamine anions by applying the DFT approach at the B3LYP/6-311 G(d,p) level of theory. The calculated results suggest that the hydroxylamine anion is more efficient than the formoximate anion at reactivating VX-inhibited AChE. The reaction of formoximate anion and the VX-AChE adduct is a three-step process, while the reaction of hydroxylamine anion with the VX-AChE adduct seems to be a two-step process. The rate-determining step in the process is the initial attack on the VX of the VX-AChE adduct by the nucleophile. The subsequent steps are exergonic in nature. The potential energy surface (PES) for the reaction of the VX-AChE adduct with hydroxylamine anion reveals that the reactivation process is facilitated by the lower free energy of activation (by a factor of 1.7 kcal mol(-1)) than that of the formoximate anion at the B3LYP/6-311 G(d,p) level of theory. The higher free energy of activation for the reverse reactivation reaction between hydroxylamine anion and the VX-serine adduct further suggests that the hydroxylamine anion is a very good antidote agent for the reactivation process. The activation barriers calculated in solvent using the polarizable continuum model (PCM) for the reactivation of the VX-AChE adduct with hydroxylamine anion were also found to be low. The calculated results suggest that V-series compounds can be more toxic than G-series compounds, which is in accord with earlier experimental observations.

Adjusting CA19-9 values to predict malignancy in obstructive jaundice: Influence of bilirubin and C-reactive protein

Science.gov (United States)

La Greca, Gaetano; Sofia, Maria; Lombardo, Rosario; Latteri, Saverio; Ricotta, Agostino; Puleo, Stefano; Russello, Domenico

2012-01-01

AIM: To find a possible relationship between inflammation and CA19-9 tumor marker by analyzing data from patients with benign jaundice (BJ) and malignant jaundice (MJ). METHODS: All patients admitted for obstructive jaundice, in the period 2005-2009, were prospectively enrolled in the study, obtaining a total of 102 patients. On admission, all patients underwent complete standard blood test examinations including C-reactive protein (CRP), bilirubin, CA19-9. Patients were considered eligible for the study when they presented obstructive jaundice confirmed by instrumental examinations and increased serum bilirubin levels (total bilirubin > 2.0 mg/dL). The standard cut-off level for CA19-9 was 32 U/mL, whereas for CRP this was 1.5 mg/L. The CA19-9 level was adjusted by dividing it by the value of serum bilirubin or by the CRP value. The patients were divided into 2 groups, MJ and BJ, and after the adjustment a comparison between the 2 groups of patients was performed. Sensitivity, specificity and positive predictive values were calculated before and after the adjustment. RESULTS: Of the 102 patients, 51 were affected by BJ and 51 by MJ. Pathologic CA19-9 levels were found in 71.7% of the patients. In the group of 51 BJ patients there were 29 (56.9%) males and 22 (43.1%) females with a median age of 66 years (range 24-96 years), whereas in the MJ group there were 24 (47%) males and 27 (53%) females, with a mean age of 70 years (range 30-92 years). Pathologic CA19-9 serum level was found in 82.3% of MJ. CRP levels were pathologic in 66.6% of the patients with BJ and in 49% with MJ. Bilirubin and CA19-9 average levels were significantly higher in MJ compared with BJ (P = 0.000 and P = 0.02), while the CRP level was significantly higher in BJ (P = 0.000). Considering a CA19-9 cut-off level of 32 U/mL, 82.3% in the MJ group and 54.9% in the BJ group were positive for CA19-9 (P = 0.002). A CA19-9 cut-off of 100 U/mL increases the difference between the two groups: 35.3% in

Measurements in Los Alamos benchmark criticals and the central reactivity discrepancy

International Nuclear Information System (INIS)

Davey, W.G.; Hansen, G.E.; Koelling, J.J.; McLaughlin, T.P.

1978-01-01

Measurements in seven Los Alamos fast critical facilities are described; all are related to elucidating the causes of the central reactivity discrepancy in fast reactors. Specific capabilities of these specialized assemblies permit measurements well-above delayed critical and these confirm the validity of the delayed neutron data used for calibration; there is therefore no reactivity-scale error. Reactivity measurements in these homogeneous assemblies exhibit no discrepancy. It is concluded that nuclear data should not be adjusted to eliminate the discrepancy found in other, heterogeneous assemblies

Digital project management the complete step-by-step guide to a successful launch

CERN Document Server

Olson, Taylor

2016-01-01

The digital world is growing and changing at a rate that can seem overwhelming to those project managers who have to keep up with it to build customer-facing solutions and applications. It's rare for project managers working in this field to be provided with much direction or a process by which to carry out a project, and there has been next to nothing available specific to these types of projects in the literary marketplace. Digital Project Management: The Complete Step-by-Step Guide to a Successful Launch was developed to fill this gap by providing the knowledge, best practices and proven steps to consistently managing these types of project successfully from end-to-end now, and in the future with just minor adjustments to adapt to changes in technology.

Comparison on genomic predictions using GBLUP models and two single-step blending methods with different relationship matrices in the Nordic Holstein population

DEFF Research Database (Denmark)

Gao, Hongding; Christensen, Ole Fredslund; Madsen, Per

2012-01-01

Background A single-step blending approach allows genomic prediction using information of genotyped and non-genotyped animals simultaneously. However, the combined relationship matrix in a single-step method may need to be adjusted because marker-based and pedigree-based relationship matrices may...... not be on the same scale. The same may apply when a GBLUP model includes both genomic breeding values and residual polygenic effects. The objective of this study was to compare single-step blending methods and GBLUP methods with and without adjustment of the genomic relationship matrix for genomic prediction of 16......) a simple GBLUP method, 2) a GBLUP method with a polygenic effect, 3) an adjusted GBLUP method with a polygenic effect, 4) a single-step blending method, and 5) an adjusted single-step blending method. In the adjusted GBLUP and single-step methods, the genomic relationship matrix was adjusted...

Real-Time Reactive Power Distribution in Microgrids by Dynamic Programing

DEFF Research Database (Denmark)

Levron, Yoash; Beck, Yuval; Katzir, Liran

2017-01-01

In this paper a new real-time optimization method for reactive power distribution in microgrids is proposed. The method enables location of a globally optimal distribution of reactive power under normal operating conditions. The method exploits the typical compact structure of microgrids to obtain...... combination of reactive powers, by means of dynamic programming. Since every single step involves a one-dimensional problem, the complexity of the solution is only linear with the number of clusters, and as a result, a globally optimal solution may be obtained in real time. The paper includes the results...

New approach to the adjustment of group cross sections fitting integral measurements

International Nuclear Information System (INIS)

Chao, Y.A.

1979-01-01

The adjustment of group cross sections fitting integral measurements is viewed as a process of estimating theoretical and/or experimental negligence errors to bring statistical consistency to the integral and differential data so that they can be combined to form an enlarged ensemble, based on which an improved estimation of the physical constants can be made. A three-step approach is suggested, and its formalism of general validity is developed. In step one, the data of negligence error are extracted from the given integral and differential data. The method of extraction is based on the concepts of prior probability and information entropy. It automatically leads to vanishing negligence error as the two sets of data are statistically consistent. The second step is to identify the sources of negligence error and adjust the data by an amount compensating for the extracted negligence discrepancy. In the last step, the two data sets, already adjusted to mutual consistency are combined as a single unified ensemble. Standard methods of statistics can then be applied to reestimate the physical constants. 1 figure

Reactivity calculation with reduction of the nuclear power fluctuations

International Nuclear Information System (INIS)

Suescun Diaz, Daniel; Senra Martinez, Aquilino

2009-01-01

A new formulation is presented in this paper for the calculation of reactivity, which is simpler than the formulation that uses the Laplace and Z transforms. A treatment is also made to reduce the intensity of the noise found in the nuclear power signal used in the calculation of reactivity. Two classes of different filters are used for that. This treatment is based on the fact that the reactivity can be written by using the compose Simpson's rule resulting in a sum of two convolution terms with response to the impulse that is characteristic of a linear system. The linear part is calculated by using the filter named finite impulse response filter (FIR). The non-linear part is calculated using the filter exponentially adjusted by the least squares method, which does not cause attenuation in the reactivity calculation.

Reactivity calculation with reduction of the nuclear power fluctuations

Energy Technology Data Exchange (ETDEWEB)

Suescun Diaz, Daniel [COPPE/UFRJ, Programa de Engenharia Nuclear, Caixa Postal 68509, CEP 21941-914 RJ (Brazil)], E-mail: dsuescun@hotmail.com; Senra Martinez, Aquilino [COPPE/UFRJ, Programa de Engenharia Nuclear, Caixa Postal 68509, CEP 21941-914 RJ (Brazil)

2009-05-15

A new formulation is presented in this paper for the calculation of reactivity, which is simpler than the formulation that uses the Laplace and Z transforms. A treatment is also made to reduce the intensity of the noise found in the nuclear power signal used in the calculation of reactivity. Two classes of different filters are used for that. This treatment is based on the fact that the reactivity can be written by using the compose Simpson's rule resulting in a sum of two convolution terms with response to the impulse that is characteristic of a linear system. The linear part is calculated by using the filter named finite impulse response filter (FIR). The non-linear part is calculated using the filter exponentially adjusted by the least squares method, which does not cause attenuation in the reactivity calculation.

Diagnostic properties of C-reactive protein for detecting pneumonia in children.

Science.gov (United States)

Koster, Madieke J; Broekhuizen, Berna D L; Minnaard, Margaretha C; Balemans, Walter A F; Hopstaken, Rogier M; de Jong, Pim A; Verheij, Theo J M

2013-07-01

The diagnostic value of C-reactive protein (CRP) level for pneumonia in children is unknown. As a first step in the assessment of the value of CRP, a diagnostic study was performed in children at an emergency department (ED). In this cross-sectional study, data were retrospectively collected from children presenting with suspected pneumonia at the ED of Antonius Hospital Nieuwegein in The Netherlands between January 2007 and January 2012. Diagnostic outcome was pneumonia yes/no according to independent radiologist. (Un)adjusted association between CRP level and pneumonia and diagnostic value of CRP were calculated. Of 687 presenting children, 286 underwent both CRP measurement and chest radiography. 148 had pneumonia (52%). The proportion of pneumonia increased with CRP level. Negative predictive values declined, but positive predictive values increased with higher CRP thresholds. Univariable odds ratio for the association between CRP level and pneumonia was 1.2 (95% CI 1.11-1.21) per 10 mg/L increase. After adjustment for baseline characteristics CRP level remained associated with pneumonia. CRP level has independent diagnostic value for pneumonia in children presenting at the ED with suspected pneumonia, but low levels do not exclude pneumonia in this setting. These results prompt evaluation of CRP in primary care children with LRTI. Copyright © 2013 Elsevier Ltd. All rights reserved.

Study to use graded cobalt adjuster in 540 MWe PHWR

International Nuclear Information System (INIS)

Raj, Manish; Fernando, M.P.S.; Pradhan, A.S.; Kumar, A.N.

2007-01-01

Full text: There are 17 adjusters in 540 MWe PHWR, which are essentially provided for xenon override function. They also provide flux flattening being in the central region of the reactor core. The present design of adjusters consists of stainless steel tube. The adjuster rods are grouped into 8 banks for movement. Since adjusters are normally fully inserted during reactor operation, they are best suited for production of cobalt 60. The nickel-plated cobalt in the form of either slugs or pellet are used for the design of cobalt pencils. The number of pencils can be varied to optimize the reactivity load and cobalt 60 production requirement. The worth and activity of cobalt adjusters have been worked out considering different pin configuration for the adjuster assembly. To start with we have assumed all adjusters throughout its length are of the same configuration. The flux depression factors within the cobalt pencils have been considered in the estimations of the specific and total cobalt 60 activities. The option of using graded cobalt adjusters, where different pin configuration along the length is considered for better flux flattening

Reactive power control methods for improved reliability of wind power inverters under wind speed variations

DEFF Research Database (Denmark)

Ma, Ke; Liserre, Marco; Blaabjerg, Frede

2012-01-01

method to relieve the thermal cycling of power switching devices under severe wind speed variations, by circulating reactive power among the parallel power converters in a WTS or among the WTS's in a wind park. The amount of reactive power is adjusted to limit the junction temperature fluctuation...

New approach to the adjustment of group cross-sections fitting integral measurements

International Nuclear Information System (INIS)

Chao, Y.A.

1979-01-01

The adjustment of group cross-sections fitting integral measurements is viewed as a process of uncovering theoretical and/or experimental negligence errors to bring statistical consistency to the integral and differential data so that they can be combined to form an enlarged ensemble, on which an improved estimation of the physical constants can be based. An approach with three steps is suggested, and its formalism of general validity is developed. In step one, the data of negligence error are extracted from the given integral and differential data. The method of extraction is based on the concepts of prior probability and information entropy. It automatically leads to vanishing negligence error as the two sets of data are statistically consistent. The second step is to identify the sources of negligence error and adjust the data by an amount compensating the extracted negligence discrepancy. In the last step the two data sets, already adjusted to mutual consistency, are combined as a single unified ensemble. Standard methods of statistics can then be applied to re-estimate the physical constants. A simple example is shown as a demonstration of the method. 1 figure

Flexible Conflict Management: Conflict Avoidance and Conflict Adjustment in Reactive Cognitive Control

Science.gov (United States)

Dignath, David; Kiesel, Andrea; Eder, Andreas B.

2015-01-01

Conflict processing is assumed to serve two crucial, yet distinct functions: Regarding task performance, control is adjusted to overcome the conflict. Regarding task choice, control is harnessed to bias decision making away from the source of conflict. Despite recent theoretical progress, until now two lines of research addressed these…

Decolorization of reactive textile dyes using water falling film dielectric barrier discharge

International Nuclear Information System (INIS)

Dojcinovic, Biljana P.; Roglic, Goran M.; Obradovic, Bratislav M.; Kuraica, Milorad M.; Kostic, Mirjana M.; Nesic, Jelena; Manojlovic, Dragan D.

2011-01-01

Highlights: → Decolorization of four reactive textile dyes using non-thermal plasma reactor. → Influence of applied energy on decolorization. → Effects of initial pH and addition of homogeneous catalysts. → Toxicity evaluation using the brine shrimp as a test organism. - Abstract: Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0 mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H 2 O 2 , Fe 2+ and Cu 2+ ) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315 kJ/L) were studied. Influence of residence time was investigated over a period of 24 h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10 mM H 2 O 2 in a system of 80.0 mg/L Reactive Black 5 with applied energy density of 45 kJ/L, after residence time of 24 h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism.

Decolorization of reactive textile dyes using water falling film dielectric barrier discharge

Energy Technology Data Exchange (ETDEWEB)

Dojcinovic, Biljana P. [Institute of Chemistry, Technology and Metallurgy, Center of Chemistry, Studentski trg 12-16, 11000 Belgrade (Serbia); Roglic, Goran M. [Faculty of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia); Obradovic, Bratislav M., E-mail: obrat@ff.bg.ac.rs [Faculty of Physics, University of Belgrade, P.O. Box 368, 11000 Belgrade (Serbia); Kuraica, Milorad M. [Faculty of Physics, University of Belgrade, P.O. Box 368, 11000 Belgrade (Serbia); Kostic, Mirjana M. [Faculty of Technology and Metallurgy, Department of Textile Engineering, Karnegijeva 4, 11000 Belgrade (Serbia); Nesic, Jelena; Manojlovic, Dragan D. [Faculty of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia)

2011-08-30

Highlights: {yields} Decolorization of four reactive textile dyes using non-thermal plasma reactor. {yields} Influence of applied energy on decolorization. {yields} Effects of initial pH and addition of homogeneous catalysts. {yields} Toxicity evaluation using the brine shrimp as a test organism. - Abstract: Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0 mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H{sub 2}O{sub 2}, Fe{sup 2+} and Cu{sup 2+}) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315 kJ/L) were studied. Influence of residence time was investigated over a period of 24 h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10 mM H{sub 2}O{sub 2} in a system of 80.0 mg/L Reactive Black 5 with applied energy density of 45 kJ/L, after residence time of 24 h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism.

MODULAR BUNDLE ADJUSTMENT FOR PHOTOGRAMMETRIC COMPUTATIONS

Directory of Open Access Journals (Sweden)

N. Börlin

2018-05-01

Full Text Available In this paper we investigate how the residuals in bundle adjustment can be split into a composition of simple functions. According to the chain rule, the Jacobian (linearisation of the residual can be formed as a product of the Jacobians of the individual steps. When implemented, this enables a modularisation of the computation of the bundle adjustment residuals and Jacobians where each component has limited responsibility. This enables simple replacement of components to e.g. implement different projection or rotation models by exchanging a module. The technique has previously been used to implement bundle adjustment in the open-source package DBAT (Börlin and Grussenmeyer, 2013 based on the Photogrammetric and Computer Vision interpretations of Brown (1971 lens distortion model. In this paper, we applied the technique to investigate how affine distortions can be used to model the projection of a tilt-shift lens. Two extended distortion models were implemented to test the hypothesis that the ordering of the affine and lens distortion steps can be changed to reduce the size of the residuals of a tilt-shift lens calibration. Results on synthetic data confirm that the ordering of the affine and lens distortion steps matter and is detectable by DBAT. However, when applied to a real camera calibration data set of a tilt-shift lens, no difference between the extended models was seen. This suggests that the tested hypothesis is false and that other effects need to be modelled to better explain the projection. The relatively low implementation effort that was needed to generate the models suggest that the technique can be used to investigate other novel projection models in photogrammetry, including modelling changes in the 3D geometry to better understand the tilt-shift lens.

Modular Bundle Adjustment for Photogrammetric Computations

Science.gov (United States)

Börlin, N.; Murtiyoso, A.; Grussenmeyer, P.; Menna, F.; Nocerino, E.

2018-05-01

In this paper we investigate how the residuals in bundle adjustment can be split into a composition of simple functions. According to the chain rule, the Jacobian (linearisation) of the residual can be formed as a product of the Jacobians of the individual steps. When implemented, this enables a modularisation of the computation of the bundle adjustment residuals and Jacobians where each component has limited responsibility. This enables simple replacement of components to e.g. implement different projection or rotation models by exchanging a module. The technique has previously been used to implement bundle adjustment in the open-source package DBAT (Börlin and Grussenmeyer, 2013) based on the Photogrammetric and Computer Vision interpretations of Brown (1971) lens distortion model. In this paper, we applied the technique to investigate how affine distortions can be used to model the projection of a tilt-shift lens. Two extended distortion models were implemented to test the hypothesis that the ordering of the affine and lens distortion steps can be changed to reduce the size of the residuals of a tilt-shift lens calibration. Results on synthetic data confirm that the ordering of the affine and lens distortion steps matter and is detectable by DBAT. However, when applied to a real camera calibration data set of a tilt-shift lens, no difference between the extended models was seen. This suggests that the tested hypothesis is false and that other effects need to be modelled to better explain the projection. The relatively low implementation effort that was needed to generate the models suggest that the technique can be used to investigate other novel projection models in photogrammetry, including modelling changes in the 3D geometry to better understand the tilt-shift lens.

MCO gas composition for low reactive surface areas

International Nuclear Information System (INIS)

Packer, M.J.

1998-01-01

This calculation adjusts modeled output (HNF-SD-SNF-TI-040, Rev. 2) by considering lower reactive fuel surface areas and by increasing the input helium backfill overpressure from 0.5 to 1.5 atm (2.5 atm abs) to verify that MCO gas-phase oxygen concentrations can remain below 4 mole % over a 40 year interim period under a worst case condition of zero reactive surface area. Added backfill gas will dilute any gases generated during interim storage and is a strategy within the current design capability. The zero reactive surface area represents a hypothetical worst case example where there is no fuel scrap and/or damaged spent fuel rods in an MCO. Also included is a hypothetical case where only K East fuel exists in an MCO with an added backfill overpressure of 0.5 atm (1.5 atm abs)

STeP: A Tool for the Development of Provably Correct Reactive and Real-Time Systems

National Research Council Canada - National Science Library

Manna, Zohar

1999-01-01

This research is directed towards the implementation of a comprehensive toolkit for the development and verification of high assurance reactive systems, especially concurrent, real time, and hybrid systems...

Automatic Adjustments of a Trans-oesophageal Ultrasound Robot for Monitoring Intra-operative Catheters

Science.gov (United States)

Wang, Shuangyi; Housden, James; Singh, Davinder; Rhode, Kawal

2017-12-01

3D trans-oesophageal echocardiography (TOE) has become a powerful tool for monitoring intra-operative catheters used during cardiac procedures in recent years. However, the control of the TOE probe remains as a manual task and therefore the operator has to hold the probe for a long period of time and sometimes in a radiation environment. To solve this problem, an add-on robotic system has been developed for holding and manipulating a commercial TOE probe. This paper focuses on the application of making automatic adjustments to the probe pose in order to accurately monitor the moving catheters. The positioning strategy is divided into an initialization step based on a pre-planning method and a localized adjustments step based on the robotic differential kinematics and related image servoing techniques. Both steps are described in the paper along with simulation experiments performed to validate the concept. The results indicate an error less than 0.5 mm for the initialization step and an error less than 2 mm for the localized adjustments step. Compared to the much bigger live 3D image volume, it is concluded that the methods are promising. Future work will focus on evaluating the method in the real TOE scanning scenario.

Proposal for a Five-Step Method to Elicit Expert Judgment

Directory of Open Access Journals (Sweden)

Duco Veen

2017-12-01

Full Text Available Elicitation is a commonly used tool to extract viable information from experts. The information that is held by the expert is extracted and a probabilistic representation of this knowledge is constructed. A promising avenue in psychological research is to incorporated experts’ prior knowledge in the statistical analysis. Systematic reviews on elicitation literature however suggest that it might be inappropriate to directly obtain distributional representations from experts. The literature qualifies experts’ performance on estimating elements of a distribution as unsatisfactory, thus reliably specifying the essential elements of the parameters of interest in one elicitation step seems implausible. Providing feedback within the elicitation process can enhance the quality of the elicitation and interactive software can be used to facilitate the feedback. Therefore, we propose to decompose the elicitation procedure into smaller steps with adjustable outcomes. We represent the tacit knowledge of experts as a location parameter and their uncertainty concerning this knowledge by a scale and shape parameter. Using a feedback procedure, experts can accept the representation of their beliefs or adjust their input. We propose a Five-Step Method which consists of (1 Eliciting the location parameter using the trial roulette method. (2 Provide feedback on the location parameter and ask for confirmation or adjustment. (3 Elicit the scale and shape parameter. (4 Provide feedback on the scale and shape parameter and ask for confirmation or adjustment. (5 Use the elicited and calibrated probability distribution in a statistical analysis and update it with data or to compute a prior-data conflict within a Bayesian framework. User feasibility and internal validity for the Five-Step Method are investigated using three elicitation studies.

Finite differences with exponential filtering in the calculation of reactivity

International Nuclear Information System (INIS)

Suescun Diaz, Daniel; Senra Martinez, Aquilino

2010-01-01

A formulation for the calculation of reactivity using a recursive process is presented in this paper, as well as the treatment to reduce noise intensity that is found in the nuclear power signal. Using the history of nuclear power considered as the memory of such power and the filter exponentially adjusted with the least squares method, it is possible to reduce the nuclear power fluctuations without causing attenuation for the calculation of reactivity and with a smaller delay than that for low-pass filter of first order delay filter. (orig.)

Finite differences with exponential filtering in the calculation of reactivity

Energy Technology Data Exchange (ETDEWEB)

Suescun Diaz, Daniel; Senra Martinez, Aquilino [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). COPPE - Programa de Engenharia Nuclear

2010-08-15

A formulation for the calculation of reactivity using a recursive process is presented in this paper, as well as the treatment to reduce noise intensity that is found in the nuclear power signal. Using the history of nuclear power considered as the memory of such power and the filter exponentially adjusted with the least squares method, it is possible to reduce the nuclear power fluctuations without causing attenuation for the calculation of reactivity and with a smaller delay than that for low-pass filter of first order delay filter. (orig.)

Photoluminescent silicon nanocrystals with chlorosilane surfaces - synthesis and reactivity

Science.gov (United States)

Höhlein, Ignaz M. D.; Kehrle, Julian; Purkait, Tapas K.; Veinot, Jonathan G. C.; Rieger, Bernhard

2014-12-01

We present a new efficient two-step method to covalently functionalize hydride terminated silicon nanocrystals with nucleophiles. First a reactive chlorosilane layer was formed via diazonium salt initiated hydrosilylation of chlorodimethyl(vinyl)silane which was then reacted with alcohols, silanols and organolithium reagents. With organolithium compounds a side reaction is observed in which a direct functionalization of the silicon surface takes place.We present a new efficient two-step method to covalently functionalize hydride terminated silicon nanocrystals with nucleophiles. First a reactive chlorosilane layer was formed via diazonium salt initiated hydrosilylation of chlorodimethyl(vinyl)silane which was then reacted with alcohols, silanols and organolithium reagents. With organolithium compounds a side reaction is observed in which a direct functionalization of the silicon surface takes place. Electronic supplementary information (ESI) available: Detailed experimental procedures and additional NMR, PL, EDX, DLS and TEM data. See DOI: 10.1039/C4NR05888G

Emotion Reactivity, Comfort Expressing Emotions, and Future Suicidal Ideation in Emerging Adults.

Science.gov (United States)

Polanco-Roman, Lillian; Moore, Alyssa; Tsypes, Aliona; Jacobson, Colleen; Miranda, Regina

2018-01-01

Emotion reactivity and difficulties in expressing emotions have been implicated in risk for suicidal behavior. This study examined comfort in expressing emotions (positive vs. negative) and depressive symptoms as mediators of the prospective relation between emotion reactivity and suicidal ideation. Emerging adults (N = 143; 72% female; 28% White) completed measures of emotion reactivity, comfort expressing emotions, and suicidal ideation at baseline and of depressive symptoms and suicidal ideation 12 months later. Emotion reactivity predicted suicidal ideation at follow-up through depressive symptoms. Difficulty expressing love-but not happiness, sadness, and anger-partially mediated the relationship between emotion reactivity and suicidal ideation at follow-up before but not after adjusting for baseline ideation. The relation between high emotion reactivity and suicidal ideation may be explained by discomfort in the expression of positive emotions and by depressive symptoms. Promotion of comfort in positive emotion expression may reduce vulnerability to suicidal ideation. © 2017 Wiley Periodicals, Inc.

In situ formation of magnetite reactive barriers in soil for waste stabilization

Science.gov (United States)

Moore, Robert C.

2003-01-01

Reactive barriers containing magnetite and methods for making magnetite reactive barriers in situ in soil for sequestering soil contaminants including actinides and heavy metals, organic materials, iodine and technetium are disclosed. According to one embodiment, a two-step reagent introduction into soil takes place. In the first step, free oxygen is removed from the soil by separately injecting into the soil aqueous solutions of iron (II) salt, for example FeCl.sub.2, and base, for example NaOH or NH.sub.3 in about a 1:1 volume ratio. Then, in the second step, similar reagents are injected a second time (however, according to about a 1:2 volume ratio, iron to salt) to form magnetite. The magnetite formation is facilitated, in part, due to slow intrusion of oxygen into the soil from the surface. The invention techniques are suited to injection of reagents into soil in proximity to a contamination plume or source allowing in situ formation of the reactive barrier at the location of waste or hazardous material. Mixing of reagents to form. precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

Design and fabrication of a chitosan hydrogel with gradient structures via a step-by-step cross-linking process.

Science.gov (United States)

Xu, Yongxiang; Yuan, Shenpo; Han, Jianmin; Lin, Hong; Zhang, Xuehui

2017-11-15

The development of scaffolds to mimic the gradient structure of natural tissue is an important consideration for effective tissue engineering. In the present study, a physical cross-linking chitosan hydrogel with gradient structures was fabricated via a step-by-step cross-linking process using sodium tripolyphosphate and sodium hydroxide as sequential cross-linkers. Chitosan hydrogels with different structures (single, double, and triple layers) were prepared by modifying the gelling process. The properties of the hydrogels were further adjusted by varying the gelling conditions, such as gelling time, pH, and composition of the crosslinking solution. Slight cytotoxicity was showed in MTT assay for hydrogels with uncross-linking chitosan solution and non-cytotoxicity was showed for other hydrogels. The results suggest that step-by-step cross-linking represents a practicable method to fabricate scaffolds with gradient structures. Copyright © 2017. Published by Elsevier Ltd.

Reactivity insertion accident analysis

International Nuclear Information System (INIS)

Moreira, J.M.L.; Nakata, H.; Yorihaz, H.

1990-04-01

The correct prediction of postulated accidents is the fundamental requirement for the reactor licensing procedures. Accident sequences and severity of their consequences depend upon the analysis which rely on analytical tools which must be validated against known experimental results. Present work presents a systematic approach to analyse and estimate the reactivity insertion accident sequences. The methodology is based on the CINETHICA code which solves the point-kinetics/thermohydraulic coupled equations with weighted temperature feedback. Comparison against SPERT experimental results shows good agreement for the step insertion accidents. (author) [pt

Determination of thermal reactivity coefficients for the first fuel loading of MO34

International Nuclear Information System (INIS)

Lueley, J.; Vrban, B.; Farkas, G.; Hascik, J.; Hinca, R.; Petriska, M.; Slugen, V.

2012-01-01

The article introduces determination of thermal reactivity coefficients, especially summarized (isothermal) and moderator (density) reactivity coefficients between 200 grad C and 260 grad C with 2 grad C step, - in compliance with the assignment - for the first fuel loading into the RC of NP Mochovce units using 2 nd generation fuel during the start-up using calculation code MCNP5 1.60. (authors)

Maternal Self-Regulation, Relationship Adjustment, and Home Chaos: Contributions to Infant Negative Emotionality

Science.gov (United States)

Bridgett, David J.; Burt, Nicole M.; Laake, Lauren M.; Oddi, Kate B.

2013-01-01

There has been increasing interest in the direct and indirect effects of parental self-regulation on children’s outcomes. In the present investigation, the effects of maternal self-regulation, home chaos, and inter-parental relationship adjustment on broad and specific indicators of infant negative emotionality (NE) were examined. A sample of maternal caregivers and their 4-month-old infants (N = 85) from a rural community participated. Results demonstrated that better maternal self-regulation was associated with lower infant NE broadly, as well as with lower infant sadness and distress to limitations/frustration and better falling reactivity (i.e. emotion regulation), specifically. Maternal self-regulation also predicted less chaotic home environments and better maternal inter-parental relationship adjustment. Findings also supported the indirect effects of maternal self-regulation on broad and specific indicators of infant NE through home chaos and maternal relationship adjustment. Some differential effects were also identified. Elevated home chaos appeared to specifically affect infant frustration/distress to limitations whereas maternal relationship adjustment affected broad infant NE, as well as several specific indicators of infant NE: frustration/distress to limitations, sadness, and falling reactivity. In conjunction with other recent investigations that have reported the effects of maternal self-regulation on parenting, the findings in the present investigation suggest that parental self-regulation may influence children’s outcomes through several proximal environmental pathways. PMID:23748168

Enhanced reactivity of dinuclear Copper(I) acetylides in dipolar cycloadditions

DEFF Research Database (Denmark)

Ahlquist, Mårten Sten Gösta; Fokin, V.V.

2007-01-01

Dinuclear alkynyl copper(I) complexes exhibit superior reactivity toward organic azides compared to their monomeric analogues. DFT studies indicate that the second copper center facilitates the formation of the cupracycle in the rate-determining step and stabilizes the metallacycle intermediate i...

Out of the picture: a study of family drawings by children from step-, single-parent, and non-step families.

Science.gov (United States)

Dunn, Judy; O'Connor, Thomas G; Levy, Irit

2002-12-01

Investigated the family drawings of 180 children ages 5 to 7 years in various family settings, including stepfather, single-parent, complex stepfamilies, and 2-parent control families. The relations of family type and biological relatedness to omission of family members and grouping of parents were examined. Children from step- and single-parent families were more likely to exclude family members than children from "control" non-step families, and exclusion was predicted from biological relatedness. Children who were biologically related to both resident parents were also more likely to group their parents together. Omission of family members was found to be associated with children's adjustment (specifically more externalizing and internalizing behavior) as reported by teachers and parents. The results indicate that biological relatedness is a salient aspect of very young children's representations of their families. The association between adjustment and exclusion of family members and grouping of parents indicates that family drawings may be useful research and clinical tools, when used in combination with other methods of assessment.

Reduction of fluctuations in reactivity using symmetric matrix

International Nuclear Information System (INIS)

Suescun D, D.; Segovia Ch, F. A.; Bonilla L, H. F.

2016-09-01

A new filtering method is presented in this work known as Savitzky-Golay (SG); allows reducing the fluctuations in the calculation of the reactivity. The filter softens and does not attenuate the nuclear power regardless of its shape, guaranteeing to decrease different degrees of noise with different steps of calculation time. This formulation employs a polynomial approximation of a certain degree to calculate the convolution coefficients. Its implementation is computational and avoids problems of bad conditioning, caused by the inversion of a linear system. The results show values in the maximum difference and in the averages absolute errors of the reactivity in comparison with that reported in the literature. (Author)

Measurement of reactivity in ADS reactors considering an exponential decay after an interruption in the external proton source

Energy Technology Data Exchange (ETDEWEB)

Henrice Junior, Edson; Gonçalves, Alessandro C., E-mail: ejunior@con.ufrj.br [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Palma, Daniel A.P., E-mail: dapalma@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro - RJ (Brazil)

2017-07-01

The online monitoring of reactivity in ADS reactors is of paramount importance for the operations of such systems. This work is dedicated to the prediction of reactivity from a decay of the neutron population after a pulse from the external source. For that, a pulse from an external source in an ADS reactor was simulated with Serpent Reactor Physics code. From the data obtained, it was possible to make an adjustment, based on a combination of exponentials. The coefficient of the exponential for the dominating term of the sum of exponentials is compared to the simplified solution of the neutron diffusion equation, thus obtaining the reactivity. The method used for the adjustment has the advantage of not requiring data that is equally spaced, and of being easily programmable, waiving the use of specific software for linear adjustments. The preliminary results of the research showed a 750 pcm deviation in relation to the value found of -3,630 pcm obtained through point kinetics, and as a result should be the object of further study. (author)

Measurement of reactivity in ADS reactors considering an exponential decay after an interruption in the external proton source

International Nuclear Information System (INIS)

Henrice Junior, Edson; Gonçalves, Alessandro C.

2017-01-01

The online monitoring of reactivity in ADS reactors is of paramount importance for the operations of such systems. This work is dedicated to the prediction of reactivity from a decay of the neutron population after a pulse from the external source. For that, a pulse from an external source in an ADS reactor was simulated with Serpent Reactor Physics code. From the data obtained, it was possible to make an adjustment, based on a combination of exponentials. The coefficient of the exponential for the dominating term of the sum of exponentials is compared to the simplified solution of the neutron diffusion equation, thus obtaining the reactivity. The method used for the adjustment has the advantage of not requiring data that is equally spaced, and of being easily programmable, waiving the use of specific software for linear adjustments. The preliminary results of the research showed a 750 pcm deviation in relation to the value found of -3,630 pcm obtained through point kinetics, and as a result should be the object of further study. (author)

Elevated maternal C-reactive protein and increased risk of schizophrenia in a national birth cohort.

Science.gov (United States)

Canetta, Sarah; Sourander, Andre; Surcel, Heljä-Marja; Hinkka-Yli-Salomäki, Susanna; Leiviskä, Jaana; Kellendonk, Christoph; McKeague, Ian W; Brown, Alan S

2014-09-01

The objective of the present study was to investigate an association between early gestational C-reactive protein, an established inflammatory biomarker, prospectively assayed in maternal sera, and schizophrenia in a large, national birth cohort with an extensive serum biobank. A nested case-control design from the Finnish Prenatal Study of Schizophrenia cohort was utilized. A total of 777 schizophrenia cases (schizophrenia, N=630; schizoaffective disorder, N=147) with maternal sera available for C-reactive protein testing were identified and matched to 777 control subjects in the analysis. Maternal C-reactive protein levels were assessed using a latex immunoassay from archived maternal serum specimens. Increasing maternal C-reactive protein levels, classified as a continuous variable, were significantly associated with schizophrenia in offspring (adjusted odds ratio=1.31, 95% confidence interval=1.10-1.56). This finding remained significant after adjusting for potential confounders, including maternal and parental history of psychiatric disorders, twin/singleton birth, urbanicity, province of birth, and maternal socioeconomic status. This finding provides the most robust evidence to date that maternal inflammation may play a significant role in schizophrenia, with possible implications for identifying preventive strategies and pathogenic mechanisms in schizophrenia and other neurodevelopmental disorders.

An improved accrual: reducing medical malpractice year-end adjustments.

Science.gov (United States)

Frese, Richard C

2012-08-01

Healthcare organizations can improve their year-end malpractice insurance accruals by taking the following steps: Maintain productive communication. Match accrual and accounting policies. Adjust amount of credit to own historical loss experience. Request more frequent analysis. Obtain a second opinion.

A Tariff for Reactive Power

Energy Technology Data Exchange (ETDEWEB)

Kueck, John D [ORNL; Kirby, Brendan J [ORNL; Li, Fangxing [ORNL; Tufon, Christopher [Pacific Gas and Electric Company; Isemonger, Alan [California Independent System Operator

2008-07-01

reduce system losses, increase circuit capacity, increase reliability, and improve efficiency. Reactive power is theoretically available from any inverter-based equipment such as photovoltaic (PV) systems, fuel cells, microturbines, and adjustable-speed drives. However, the installation is usually only economical if reactive power supply is considered during the design and construction phase. In this report, we find that if the inverters of PV systems or the generators of combined heat and power (CHP) systems were designed with capability to supply dynamic reactive power, they could do this quite economically. In fact, on an annualized basis, these inverters and generators may be able to supply dynamic reactive power for about $5 or $6 per kVAR. The savings from the local supply of dynamic reactive power would be in reduced losses, increased capacity, and decreased transmission congestion. The net savings are estimated to be about $7 per kVAR on an annualized basis for a hypothetical circuit. Thus the distribution company could economically purchase a dynamic reactive power service from customers for perhaps $6/kVAR. This practice would provide for better voltage regulation in the distribution system and would provide an alternate revenue source to help amortize the cost of PV and CHP installations. As distribution and transmission systems are operated under rising levels of stress, the value of local dynamic reactive supply is expected to grow. Also, large power inverters, in the range of 500 kW to 1 MW, are expected to decrease in cost as they become mass produced. This report provides one data point which shows that the local supply of dynamic reactive power is marginally profitable at present for a hypothetical circuit. We expect that the trends of growing power flow on the existing system and mass production of inverters for distributed energy devices will make the dynamic supply of reactive power from customers an integral component of economical and reliable

AIREKMOD-RR, Reactivity Transients in Nuclear Research Reactors

International Nuclear Information System (INIS)

Baggoura, B.; Mazrou, H.

2001-01-01

1 - Description of program or function: AIREMOD-RR is a point kinetics code which can simulate fast transients in nuclear research reactor cores. It can also be used for theoretical reactor dynamics studies. It is used for research reactor kinetic analysis and provides a point neutron kinetic capability. The thermal hydraulic behavior is governed by a one-dimensional heat balance equation. The calculations are restricted to a single equivalent unit cell which consists of fuel, clad and coolant. 2 - Method of solution: For transient reactor kinetic calculations a modified Runge Kutta numerical method is used. The external reactivity insertion, specified as a function of time, is converted in dollar ($) unit. The neutron density, energy release and feedback variables are given at each time step. The two types of reactivity feedback considered are: Doppler effect and moderator effect. A new expression for the reactivity dependence on the feedback variables has been introduced in the present version of the code. The feedback reactivities are fitted in power series expression. 3 - Restrictions on the complexity of the problem: The number of delayed neutron groups and the total number of equations are limited only by computer storage capabilities. - Coolant is always in liquid phase. - Void reactivity feedback is not considered

Sexual orientation modulates endocrine stress reactivity.

Science.gov (United States)

Juster, Robert-Paul; Hatzenbuehler, Mark L; Mendrek, Adrianna; Pfaus, James G; Smith, Nathan Grant; Johnson, Philip Jai; Lefebvre-Louis, Jean-Philippe; Raymond, Catherine; Marin, Marie-France; Sindi, Shireen; Lupien, Sonia J; Pruessner, Jens C

2015-04-01

Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor. The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences. Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their "coming out"). Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly. Copyright © 2015 Society of Biological Psychiatry. Published

Sexual Orientation Modulates Endocrine Stress Reactivity

Science.gov (United States)

Juster, Robert-Paul; Hatzenbuehler, Mark L.; Mendrek, Adrianna; Pfaus, James G.; Smith, Nathan Grant; Johnson, Philip Jai; Lefebvre-Louis, Jean-Philippe; Raymond, Catherine; Marin, Marie-France; Sindi, Shireen; Lupien, Sonia J.; Pruessner, Jens C.

2015-01-01

BACKGROUND Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor. METHODS The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences. RESULTS Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their “coming out”). CONCLUSIONS Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly. PMID:25444167

Evaluation of bituminized waste reactivity

International Nuclear Information System (INIS)

Camaro, S.; Moulinier, D.

2000-01-01

The bituminization process has been used for conditioning low and medium level (LML) radioactive waste, particularly to immobilize coprecipitation slurries and evaporation concentrates generated by effluent treatment. The process consists in mixing bitumen matrix with inactive soluble and slightly soluble salts added to insolubilize the radionuclides or resulting from the neutralization of acid effluents. This operation is performed at a sufficient temperature - depending on waste composition and bitumen grade to ensure the flow of the resulting mixture into metal containers. Exothermicity due to salts/salts or salts/bitumen reactions depending on the type of waste can be induced during or after the mixing step. This could produce an additional heat emission that the drum must be able to release to avoid a potentially incidental pattern with ignition risk, explaining why the CEA has been involved in evaluating the thermal reactivity of bituminized waste and its repercussions on the bituminization process. Given the difficulty of discriminating each exothermal reaction, the characterization of a global reactivity appears as a further precautionary measure, in addition to the definition of a working safety margin. The CEA has accordingly developed studies on this aspect. The article discusses the experimental methodology developed for the determination of the global reactivity. (authors)

Unifying Model-Based and Reactive Programming within a Model-Based Executive

Science.gov (United States)

Williams, Brian C.; Gupta, Vineet; Norvig, Peter (Technical Monitor)

1999-01-01

Real-time, model-based, deduction has recently emerged as a vital component in AI's tool box for developing highly autonomous reactive systems. Yet one of the current hurdles towards developing model-based reactive systems is the number of methods simultaneously employed, and their corresponding melange of programming and modeling languages. This paper offers an important step towards unification. We introduce RMPL, a rich modeling language that combines probabilistic, constraint-based modeling with reactive programming constructs, while offering a simple semantics in terms of hidden state Markov processes. We introduce probabilistic, hierarchical constraint automata (PHCA), which allow Markov processes to be expressed in a compact representation that preserves the modularity of RMPL programs. Finally, a model-based executive, called Reactive Burton is described that exploits this compact encoding to perform efficIent simulation, belief state update and control sequence generation.

78 FR 40665 - Cost Accounting Standards: CAS 413 Pension Adjustments for Extraordinary Events

Science.gov (United States)

2013-07-08

... Accounting Standards: CAS 413 Pension Adjustments for Extraordinary Events AGENCY: Cost Accounting Standards...: The Office of Federal Procurement Policy (OFPP), Cost Accounting Standards (CAS) Board, is conducting... Extraordinary Events. This is the first step in a four- step process that may result in a final rule. As part of...

Heterogeneously catalyzed reactive extraction for biomass valorization into chemicals and fuels

NARCIS (Netherlands)

Ordomskiy, V.; Khodakov, A.Y.; Nijhuis, T.A.; Schouten, J.C.

2015-01-01

This paper focuses on the heterogeneously catalyzed reactive extraction and separation in reaction steps in organic and aqueous phases during the transformation of biomass derived products. Two approaches are demonstrated for decomposing and preserving routes for biomass transformation into valuable

The effect of step stool use and provider height on CPR quality during pediatric cardiac arrest: A simulation-based multicentre study.

Science.gov (United States)

Cheng, Adam; Lin, Yiqun; Nadkarni, Vinay; Wan, Brandi; Duff, Jonathan; Brown, Linda; Bhanji, Farhan; Kessler, David; Tofil, Nancy; Hecker, Kent; Hunt, Elizabeth A

2018-01-01

We aimed to explore whether a) step stool use is associated with improved cardiopulmonary resuscitation (CPR) quality; b) provider adjusted height is associated with improved CPR quality; and if associations exist, c) determine whether just-in-time (JIT) CPR training and/or CPR visual feedback attenuates the effect of height and/or step stool use on CPR quality. We analysed data from a trial of simulated cardiac arrests with three study arms: No intervention; CPR visual feedback; and JIT CPR training. Step stool use was voluntary. We explored the association between 1) step stool use and CPR quality, and 2) provider adjusted height and CPR quality. Adjusted height was defined as provider height + 23 cm (if step stool was used). Below-average height participants were ≤ gender-specific average height; the remainder were above average height. We assessed for interaction between study arm and both adjusted height and step stool use. One hundred twenty-four subjects participated; 1,230 30-second epochs of CPR were analysed. Step stool use was associated with improved compression depth in below-average (female, p=0.007; male, pstep stool use (pStep stool use is associated with improved compression depth regardless of height. Increased provider height is associated with improved compression depth, with visual feedback attenuating the effects of height and step stool use.

Methane dissociation on the steps and terraces of Pt(211) resolved by quantum state and impact site

Science.gov (United States)

Chadwick, Helen; Guo, Han; Gutiérrez-González, Ana; Menzel, Jan Paul; Jackson, Bret; Beck, Rainer D.

2018-01-01

Methane dissociation on the step and terrace sites of a Pt(211) single crystal was studied by reflection absorption infrared spectroscopy (RAIRS) at a surface temperature of 120 K. The C—H stretch RAIRS signal of the chemisorbed methyl product species was used to distinguish between adsorption on step and terrace sites allowing methyl uptake to be monitored as a function of incident kinetic energy for both sites. Our results indicate a direct dissociation mechanism on both sites with higher reactivity on steps than on terraces consistent with a difference in an activation barrier height of at least 30 kJ/mol. State-specific preparation of incident CH4 with one quantum of antisymmetric (ν3) stretch vibration further increases the CH4 reactivity enabling comparison between translational and vibrational activation on both steps and terraces. The reaction is modeled with first principles quantum theory that accurately describes dissociative chemisorption at different sites on the surface.

Dimensions of Adversity, Physiological Reactivity, and Externalizing Psychopathology in Adolescence: Deprivation and Threat.

Science.gov (United States)

Busso, Daniel S; McLaughlin, Katie A; Sheridan, Margaret A

Dysregulation of autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis function is a putative intermediate phenotype linking childhood adversity (CA) with later psychopathology. However, associations of CAs with autonomic nervous system and HPA-axis function vary widely across studies. Here, we test a novel conceptual model discriminating between distinct forms of CA (deprivation and threat) and examine their independent associations with physiological reactivity and psychopathology. Adolescents (N = 169; mean [SD] age, 14.9 [1.4] years) with a range of interpersonal violence (e.g., maltreatment, community violence) and poverty exposure participated in the Trier Social Stress test (TSST). During the TSST, electrocardiogram, impedance cardiograph, salivary cortisol, and dehydroepiandrosterone-sulfate data were collected. We compared the associations of poverty (an indicator of deprivation) and interpersonal violence (an indicator of threat) on sympathetic, parasympathetic, and HPA-axis reactivity to the TSST, and assessed whether these differences mediated the association of adversity with internalizing and externalizing symptoms. Exposure to poverty and interpersonal violence was associated with psychopathology. Interpersonal violence, adjusting for poverty, was associated with blunted sympathetic (b = 1.44, p = .050) and HPA-axis reactivity (b = -.09; p = .021). Blunted cortisol reactivity mediated the association of interpersonal violence with externalizing, but not internalizing, psychopathology. In contrast, poverty was not associated with physiological reactivity after adjusting for interpersonal violence. We provide evidence for distinct neurobiological mechanisms through which adversity related to poverty and interpersonal violence is associated with psychopathology in adolescence. Distinguishing distinct pathways through which adversity influences mental health has implications for preventive interventions targeting youths exposed to

Knee Trembling During Freezing of Gait Represents Multiple Anticipatory Postural Adjustments

Science.gov (United States)

Jacobs, Jesse V.; Nutt, John G.; Carlson-Kuhta, Patricia; Stephens, Marilee; Horak, Fay B.

2011-01-01

Freezing of gait (FoG) is an episodic, brief inability to step that delays gait initiation or interrupts ongoing gait. FoG is often associated with an alternating shaking of the knees, clinically referred to as knee trembling or trembling in place. The pathophysiology of FoG and of the concomitant trembling knees is unknown; impaired postural adjustment in preparation for stepping is one hypothesis. We examined anticipatory postural adjustments (APAs) prior to protective steps induced by a forward loss of balance in 10 Parkinson’s disease (PD) subjects with marked FoG and in 10 control subjects. The amplitude and timing of the APAs were determined from changes in the vertical ground-reaction forces recorded by a force plate under each foot and were confirmed by electromyographic recordings of bilateral medial gastrocnemius, tibialis anterior and tensor fascia latae muscles. Protective steps were accomplished with a single APA followed by a step for control subjects, whereas PD subjects frequently exhibited multiple, alternating APAs coexistent with the knee trembling commonly observed during FoG as well as delayed, inadequate or no stepping. These multiple APAs were not delayed in onset and were of similar or larger amplitude than the single APAs exhibited by the control subjects. These observations suggest that multiple APAs produce the knee trembling commonly associated with FoG and that FoG associated with a forward loss of balance is caused by an inability to couple a normal APA to the stepping motor pattern. PMID:19061889

One-step uniformly hybrid carbon quantum dots with high-reactive TiO{sub 2} for photocatalytic application

Energy Technology Data Exchange (ETDEWEB)

Wang, Wei [School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology, Nanjing 210044 (China); Ni, Yaru; Xu, Zhongzi [College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009 (China)

2015-02-15

Highlights: • CQDs were uniformly deposited on high-reactive TiO{sub 2} by a one-pot method. • CQDs can use a wide range of solar spectrum efficiently for photocatalysis. • TiO{sub 2} facets are not affected and the total photocatalytic activity was improved. - Abstract: High-reactive facets dominated anatase TiO{sub 2} is of great significance to solve environment and energy challenges. Maintaining the pristine structure and improving the photocatalytic activity of TiO{sub 2} still need innovation work by employing different modification processes. Here, carbon quantum dots (CQDs) were employed to modify TiO{sub 2} with exposed {0 0 1}, {1 0 1}, and {0 1 0} facets by a one-pot hydrothermal method. Results indicate that CQDs can disperse uniformly on TiO{sub 2} surface, and the high-reactive facets are maintained perfectly. The introduced CQDs can both enhance the light absorption and suppress photogenerated electron-hole’s recombination. Proper amount of introduced CQDs can both significantly enhance the photocatalytic activities, which are very stable, under the UV and visible light irradiation Corresponding photocatalytic mechanisms are also discussed in the present work.

Nuclear data for the calculation of thermal reactor reactivity coefficients

International Nuclear Information System (INIS)

1989-01-01

On its 15th meeting in Vienna, 16-20 June 1986, the International Nuclear Data Committee (INDC) considered it important to review the accuracy with which changes in thermal reactor reactivity resulting from changes in temperature and coolant density can be predicted. It was noted that reactor physicists in several countries had to adjust the thermal neutron cross-section data base in order to reproduce measured reactivity coefficients. Consequently, it appeared to be essential to examine the consistency of the integral and differential cross-section data and to make all the information available which has a bearing on reactivity coefficient prediction. Following the recommendation of the INDC, the Nuclear Data Section of the International Atomic Energy Agency, therefore, convened the Advisory Group Meeting on Nuclear Data for the Calculation of Thermal Reaction Reactivity Coefficients, in Vienna, Austria, 7-10 Dec. 1987. The Conclusions and Recommendations of the meeting together with the papers presented, are submitted in the present document. A separate abstract was prepared for each of these 12 papers. Refs, figs and tabs

Pulse shape adjustment for the SLC damping ring kickers

International Nuclear Information System (INIS)

Mattison, T.; Cassel, R.; Donaldson, A.; Fischer, H.; Gough, D.

1991-05-01

The difficulties with damping ring kickers that prevented operation of the SLAC Linear Collider in full multiple bunch mode have been overcome by shaping the current pulse to compensate for imperfections in the magnets. The risetime was improved by a peaking capacitor, with a tunable inductor to provide a locally flat pulse. The pulse was flattened by an adjustable droop inductor. Fine adjustment was provided by pulse forming line tuners driven by stepping motors. Further risetime improvement will be obtained by a saturating ferrite pulse sharpener. 4 refs., 3 figs

Cardiovascular Reactivity in Patients With Major Depressive Disorder With High- or Low-Level Depressive Symptoms: A Cross-Sectional Comparison of Cardiovascular Reactivity to Laboratory-Induced Mental Stress.

Science.gov (United States)

Wang, Mei-Yeh; Chiu, Chen-Huan; Lee, Hsin-Chien; Su, Chien-Tien; Tsai, Pei-Shan

2016-03-01

Depression increases the risk of adverse cardiac events. Cardiovascular reactivity is defined as the pattern of cardiovascular responses to mental stress. An altered pattern of cardiovascular reactivity is an indicator of subsequent cardiovascular disease. Because depression and adverse cardiac events may have a dose-dependent association, this study examined the differences in cardiovascular reactivity to mental stress between patients with major depressive disorder (MDD) with high depression levels and those with low depression levels. Moreover, autonomic nervous system regulation is a highly plausible biological mechanism for the pattern of cardiovascular reactivity to mental stress. The association between cardiovascular reactivity and parameters of heart rate variability (HRV), an index for quantifying autonomic nervous system activity modulation, was thus examined. This study included 88 patients with MDD. HRV was measured before stress induction. The Stroop Color and Word Test and mirror star-tracing task were used to induce mental stress. We observed no significant association between depressive symptom level and any of the cardiovascular reactivity parameters. Cardiovascular reactivity to mental stress was comparable between patients with MDD with high-level depressive symptoms and those with low-level depressive symptoms. After adjusting for confounding variables, the high-frequency domain of HRV was found to be an independent predictor of the magnitude of heart rate reactivity (β = -.33, p = .002). In conclusion, the magnitude of cardiovascular reactivity may be independent of depression severity in patients with MDD. The autonomic regulation of cardiovascular responses to mental stress primarily influences heart rate reactivity in patients with MDD. © The Author(s) 2015.

Evaluation of the oxide and silicide fuels reactivity in the RSG-GAS core

International Nuclear Information System (INIS)

S, Tukiran; M S, Tagor; S, Lily; Pinem, S.

2000-01-01

Fuel exchange of The RSG-GAS reactor core from uranium oxide to uranium silicide in the same loading, density, and enrichment, that is, 250 gr, 2.98 gr/cm 3 , and 19.75 % respectively, will be performed in-step wise. In every cycle of exchange with 5/l mode, it is needed to evaluate the parameter of reactor core operation. One of the important operation parameters is fuel reactivity that gives effect to the core reactivity. The experiment was performed at core no. 36, BOC, low power which exist 2 silicide fuels. The evaluation was done based on the RSG-GAS control rod calibration consisting of 40 fuels and 8 control rod.s. From 40 fuels in the core, there are 2 silicide fuels, RI-225/A-9 and RI-224/C-3. For inserting 2 silicide fuels, the reactivity effect to the core must be know. To know this effect , it was performed fuels reactivity experiment, which based on control rod calibration. But in this case the RSG-GAS has no other fresh oxide fuel so that configuration of the RSG-GAS core was rearranged by taking out the both silicide fuels and this configuration is used as reference core. Then silicide fuel RI-224 was inserted to position F-3 replacing the fresh oxide fuel RI-260 so the different reactivity of the fuels is obtained. The experiment result showed that the fuel reactivity change is in amount of 12.85 cent (0.098 % ) The experiment result was compared to the calculation result, using IAFUEL code which amount to 13.49 cent (0.103 %) The result showed that the reactivity change of oxide to silicide fuel is small so that the fuel exchange from uranium oxide to uranium silicide in the first step can be done without any significant change of the operation parameter

The Throw-and-Catch Model of Human Gait: Evidence from Coupling of Pre-Step Postural Activity and Step Location

Science.gov (United States)

Bancroft, Matthew J.; Day, Brian L.

2016-01-01

Postural activity normally precedes the lift of a foot from the ground when taking a step, but its function is unclear. The throw-and-catch hypothesis of human gait proposes that the pre-step activity is organized to generate momentum for the body to fall ballistically along a specific trajectory during the step. The trajectory is appropriate for the stepping foot to land at its intended location while at the same time being optimally placed to catch the body and regain balance. The hypothesis therefore predicts a strong coupling between the pre-step activity and step location. Here we examine this coupling when stepping to visually-presented targets at different locations. Ten healthy, young subjects were instructed to step as accurately as possible onto targets placed in five locations that required either different step directions or different step lengths. In 75% of trials, the target location remained constant throughout the step. In the remaining 25% of trials, the intended step location was changed by making the target jump to a new location 96 ms ± 43 ms after initiation of the pre-step activity, long before foot lift. As predicted by the throw-and-catch hypothesis, when the target location remained constant, the pre-step activity led to body momentum at foot lift that was coupled to the intended step location. When the target location jumped, the pre-step activity was adjusted (median latency 223 ms) and prolonged (on average by 69 ms), which altered the body’s momentum at foot lift according to where the target had moved. We conclude that whenever possible the coupling between the pre-step activity and the step location is maintained. This provides further support for the throw-and-catch hypothesis of human gait. PMID:28066208

The Throw-and-Catch Model of Human Gait: Evidence from Coupling of Pre-Step Postural Activity and Step Location.

Science.gov (United States)

Bancroft, Matthew J; Day, Brian L

2016-01-01

Postural activity normally precedes the lift of a foot from the ground when taking a step, but its function is unclear. The throw-and-catch hypothesis of human gait proposes that the pre-step activity is organized to generate momentum for the body to fall ballistically along a specific trajectory during the step. The trajectory is appropriate for the stepping foot to land at its intended location while at the same time being optimally placed to catch the body and regain balance. The hypothesis therefore predicts a strong coupling between the pre-step activity and step location. Here we examine this coupling when stepping to visually-presented targets at different locations. Ten healthy, young subjects were instructed to step as accurately as possible onto targets placed in five locations that required either different step directions or different step lengths. In 75% of trials, the target location remained constant throughout the step. In the remaining 25% of trials, the intended step location was changed by making the target jump to a new location 96 ms ± 43 ms after initiation of the pre-step activity, long before foot lift. As predicted by the throw-and-catch hypothesis, when the target location remained constant, the pre-step activity led to body momentum at foot lift that was coupled to the intended step location. When the target location jumped, the pre-step activity was adjusted (median latency 223 ms) and prolonged (on average by 69 ms), which altered the body's momentum at foot lift according to where the target had moved. We conclude that whenever possible the coupling between the pre-step activity and the step location is maintained. This provides further support for the throw-and-catch hypothesis of human gait.

K Basin Sludge Conditioning Process Testing Partitioning of PCBs in Dissolver Solution After Neutralization/Precipitation (Caustic Adjustment)

International Nuclear Information System (INIS)

Schmidt, A.J.; Thornton, B.M.; Hoppe, E.W.; Mong, G.M.; Silvers, K.L.; Slate, S.O.

1999-01-01

The purpose of the work described in this report was to gain a better understanding of how PCB congeners present in a simulated K Basin sludge dissolver solution will partition upon neutralization and precipitation (i.e., caustic adjustment). In a previous study (Mong et al. 1998),the entire series of sludge conditioning steps (acid dissolution, filtration, and caustic adjustment) were examined during integrated testing. In the work described here, the caustic adjustment step was isolated to examine the fate of PCBs in more detail within this processing step. For this testing, solutions of dissolver simulant (containing no solids) with a known initial concentration of PCB congeners were neutralized with caustic to generate a clarified supernatant and a settled sludge phase. PCBs were quantified in each phase (including the PCBs associated with the test vessel rinsates), and material balance information was collected

Calculation of homogenized Pickering NGS stainless steel adjuster rod neutron cross-sections using conservation of reaction rates

Energy Technology Data Exchange (ETDEWEB)

Robinson, R C [Atlantic Nuclear Services Ltd. (Canada); Tran, F [Ontario Hydro, Pickering, ON (Canada). Pickering Generating Station

1996-12-31

A homogenization methodology for calculation of reactivity device incremental cross-sections has been developed using reaction rate conservation (RRC). A heterogeneous transport calculation of flux was utilised to produce the homogenized cross-sections for a finite difference two group diffusion code. The RRC cross-sections have been shown to improve significantly the prediction of reactivity worth for stainless steel adjuster rods installed in Pickering NGS reactors. (author). 10 refs., 3 tabs., 6 figs.

Zinc hexacyanoferrate film as an effective protecting layer in two-step and one-step electropolymerization of pyrrole on zinc substrate

Energy Technology Data Exchange (ETDEWEB)

Pournaghi-Azar, M.H. [Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)]. E-mail: pournaghiazar@tabrizu.ac.ir; Nahalparvari, H. [Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

2005-03-15

The two-step and one-step electrosynthesis processes of polypyrrole (PPy) films on the zinc substrate are described. The two-step process includes (i) the zinc surface pretreatment with hexacyanoferrate ion in the aqueous medium in order to form a zinc hexacyanoferrate (ZnHCF) film non-blocking passive layer on the surface and with the view to prevent its reactivity and (ii) electropolymerization of pyrrole on the ZnHCF vertical bar Zn-modified electrode in aqueous pyrrole solution. In this context, both the non-electrolytic and electrolytic procedures were adapted, and the effect of some experimental conditions such as supporting electrolyte, pH and temperature of the solution at the zinc surface pretreatment step as well as pyrrole concentration and electrochemical techniques at the polymerization step was investigated. By optimizing the experimental conditions in both steps, we have obtained a homogeneous and strongly adherent PPy films on the zinc substrate. The one-step process is based on the use of an aqueous medium containing Fe(CN){sub 6}{sup 4-} and pyrrole. The ferrocyanide ion passivates the substrate by formation of ZnHCF film during the electropolymerization process of pyrrole and therefore makes it possible to obtain strongly adherent PPy films, with controlled thickness, either by cyclic voltammetry or by electrolysis at constant current or constant potential without any previously treatment of the zinc electrode surface. The polypyrrole films deposited on the zinc electrode were characterized by cyclic voltammetry and scanning electron microscopic (SEM) measurement.

Zinc hexacyanoferrate film as an effective protecting layer in two-step and one-step electropolymerization of pyrrole on zinc substrate

International Nuclear Information System (INIS)

Pournaghi-Azar, M.H.; Nahalparvari, H.

2005-01-01

The two-step and one-step electrosynthesis processes of polypyrrole (PPy) films on the zinc substrate are described. The two-step process includes (i) the zinc surface pretreatment with hexacyanoferrate ion in the aqueous medium in order to form a zinc hexacyanoferrate (ZnHCF) film non-blocking passive layer on the surface and with the view to prevent its reactivity and (ii) electropolymerization of pyrrole on the ZnHCF vertical bar Zn-modified electrode in aqueous pyrrole solution. In this context, both the non-electrolytic and electrolytic procedures were adapted, and the effect of some experimental conditions such as supporting electrolyte, pH and temperature of the solution at the zinc surface pretreatment step as well as pyrrole concentration and electrochemical techniques at the polymerization step was investigated. By optimizing the experimental conditions in both steps, we have obtained a homogeneous and strongly adherent PPy films on the zinc substrate. The one-step process is based on the use of an aqueous medium containing Fe(CN) 6 4- and pyrrole. The ferrocyanide ion passivates the substrate by formation of ZnHCF film during the electropolymerization process of pyrrole and therefore makes it possible to obtain strongly adherent PPy films, with controlled thickness, either by cyclic voltammetry or by electrolysis at constant current or constant potential without any previously treatment of the zinc electrode surface. The polypyrrole films deposited on the zinc electrode were characterized by cyclic voltammetry and scanning electron microscopic (SEM) measurement

Stepping to the Beat: Feasibility and Potential Efficacy of a Home-Based Auditory-Cued Step Training Program in Chronic Stroke

Directory of Open Access Journals (Sweden)

Rachel L. Wright

2017-08-01

Full Text Available BackgroundHemiparesis after stroke typically results in a reduced walking speed, an asymmetrical gait pattern and a reduced ability to make gait adjustments. The purpose of this pilot study was to investigate the feasibility and preliminary efficacy of home-based training involving auditory cueing of stepping in place.MethodsTwelve community-dwelling participants with chronic hemiparesis completed two 3-week blocks of home-based stepping to music overlaid with an auditory metronome. Tempo of the metronome was increased 5% each week. One 3-week block used a regular metronome, whereas the other 3-week block had phase shift perturbations randomly inserted to cue stepping adjustments.ResultsAll participants reported that they enjoyed training, with 75% completing all training blocks. No adverse events were reported. Walking speed, Timed Up and Go (TUG time and Dynamic Gait Index (DGI scores (median [inter-quartile range] significantly improved between baseline (speed = 0.61 [0.32, 0.85] m⋅s−1; TUG = 20.0 [16.0, 39.9] s; DGI = 14.5 [11.3, 15.8] and post stepping training (speed = 0.76 [0.39, 1.03] m⋅s−1; TUG = 16.3 [13.3, 35.1] s; DGI = 16.0 [14.0, 19.0] and was maintained at follow-up (speed = 0.75 [0.41, 1.03] m⋅s−1; TUG = 16.5 [12.9, 34.1] s; DGI = 16.5 [13.5, 19.8].ConclusionThis pilot study suggests that auditory-cued stepping conducted at home was feasible and well-tolerated by participants post-stroke, with improvements in walking and functional mobility. No differences were detected between regular and phase-shift training with the metronome at each assessment point.

Validation of DRAGON side-step method for Bruce-A restart Phase-B physics tests

International Nuclear Information System (INIS)

Shen, W.; Ngo-Trong, C.; Davis, R.S.

2004-01-01

The DRAGON side-step method, developed at AECL, has a number of advantages over the all-DRAGON method that was used before. It is now the qualified method for reactivity-device calculations. Although the side-step-method-generated incremental cross sections have been validated against those previously calculated with the all-DRAGON method, it is highly desirable to validate the side-step method against device-worth measurements in power reactors directly. In this paper, the DRAGON side-step method was validated by comparison with the device-calibration measurements made in Bruce-A NGS Unit 4 restart Phase-B commissioning in 2003. The validation exercise showed excellent results, with the DRAGON code overestimating the measured ZCR worth by ∼5%. A sensitivity study was also performed in this paper to assess the effect of various DRAGON modelling techniques on the incremental cross sections. The assessment shows that the refinement of meshes in 3-D and the use of the side-step method are two major reasons contributing to the improved agreement between the calculated ZCR worths and the measurements. Use of different DRAGON versions, DRAGON libraries, local-parameter core conditions, and weighting techniques for the homogenization of tube clusters inside the ZCR have a very small effect on the ZCR incremental thermal absorption cross section and ZCR reactivity worth. (author)

Obtaining incremental multigroup cross sections for CANDU super cells with reactivity devices

International Nuclear Information System (INIS)

Balaceanu, V.; Constantin, M.

2001-01-01

In the last 20 years a multigroup methodology WIMS - PIJXYZ (WP) was developed and validated at INR Pitesti for obtaining incremental cross sections for reactivity devices in CANDU reactors. This is an alternate methodology to the CANDU classic methodology (experimentally adjusted) based on the POWDERPUFS and MULTICELL computer codes. The 2D supercell calculation performed with the WIMS code, that is a NEA Data Bank transport code, and which produces multigroup cross sections (on 18 energy groups) for CANDU supercell material (standard and perturbed, with and without reactivity devices). To obtain an as correct as possible 3D modelling for the CANDU supercells containing reactivity devices, the WIMS cross sections are used as input data for the PIJXYZ code, thus obtaining homogenized cross sections for CANDU supercells. PIJXYZ is an integral transport code based on the formalism of the first collision probabilities. It is analogue to the SHETAN code and it was created for neutron analyzes at cell level for CANDU type reactors were the reactivity devices are perpendicular to the fuel channels. The coordinate system used in PIJXYZ is a mixed one, namely a rectangular-cylindrical system. The geometric model used in PIJXYZ is presented. The fuel beam is represented by a horizontal cylinder and the reactivity device by a vertical one both cylinders being immersed in the moderator. Two supercell types were considered: a perturbed supercell (containing a reactivity device) and the standard supercell were the place of reactivity device is occupied by the moderator. The incremental cross sections for reactivity device are obtained as differences between the homogenized over supercell cross sections (with reactivity device) and homogenized over standards supercell (without device) cross sections. The PIJXYZ computation may be done on an energy cutting with 2 up to 18 groups. The validation of VIMS - PIJXYZ was done on the basis of several benchmark and by comparison with

An Enhanced Islanding Microgrid Reactive Power, Imbalance Power, and Harmonic Power Sharing Scheme

DEFF Research Database (Denmark)

He, Jinwei; Lin, Yun Wei; Blaabjerg, Frede

2015-01-01

To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through online virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power, or harmonic power is added to the conventional real power...

A kinematic analysis of the rapid step test in balance-impaired and unimpaired older women.

Science.gov (United States)

Schulz, Brian W; Ashton-Miller, James A; Alexander, Neil B

2007-04-01

Little is known about the kinematic and kinetic determinants that might explain age and balance-impairment alterations in the results of volitional stepping performance tests. Maximal unipedal stance time (UST) was used to distinguish "balance-impaired" old (BI, UST30s, N=12, mean age=71 years) before they and healthy young females (Y, UST>30s, N=13, mean age=23 years) performed the rapid step test (RST). The RST evaluates the time required to take volitional front, side, and back steps of at least 80% maximum step length in response to verbal commands. Kinematic and kinetic data were recorded during the RST. The results indicate that the initiation phase of the step was the major source of age- and balance impairment-related delays. The delays in BI were primarily caused by increased postural adjustments prior to step initiation, as measured by center-of-pressure (COP) path length (p<0.003). The Step landing phase showed similar, but non-significant, temporal trends. Step length and peak center-of-mass (COM) deceleration during the Step-Out landing decreased in O by 18% (p=0.0002) and 24% (p=0.001), respectively, and a further 12% (p=0.04) and 18% (p=0.08) in BI. We conclude that the delay in BI step initiation was due to the increase in their postural adjustments prior to step initiation.

Droop Control with an Adjustable Complex Virtual Impedance Loop based on Cloud Model Theory

DEFF Research Database (Denmark)

Li, Yan; Shuai, Zhikang; Xu, Qinming

2016-01-01

Droop control framework with an adjustable virtual impedance loop is proposed in this paper, which is based on the cloud model theory. The proposed virtual impedance loop includes two terms: a negative virtual resistor and an adjustable virtual inductance. The negative virtual resistor term...... sometimes. The cloud model theory is applied to get online the changing line impedance value, which relies on the relevance of the reactive power responding the changing line impedance. The verification of the proposed control strategy is done according to the simulation in a low voltage microgrid in Matlab....

Autonomous Reactivity Control (ARC) — Principles, geometry and design process

Energy Technology Data Exchange (ETDEWEB)

Qvist, Staffan A., E-mail: staffan.qvist@physics.uu.se [Department of Physics and Astronomy, Uppsala University, Uppsala (Sweden); Department of Nuclear Engineering, University of California Berkeley (United States); Hellesen, Carl [Department of Physics and Astronomy, Uppsala University, Uppsala (Sweden); Thiele, Roman [Division of Reactor Technology, Royal Institute of Technology, Stockholm (Sweden); Dubberley, Allen E. [General Electric Advanced Reactor Systems Department (retired), Sunnyvale, CA (United States); Gradecka, Malwina; Greenspan, Ehud [Department of Nuclear Engineering, University of California Berkeley (United States)

2016-10-15

Highlights: • Here we define the principles of the operation and design of ARC systems. • ARC systems can provide inherent safety during and following unprotected transients. • A manufacturing and assembly method was developed and presented. - Abstract: The Autonomous Reactivity Control (ARC) system was developed to ensure inherent safety performance of Generation-IV reactors while having a minimal impact on reactor performance and economic viability. Here we present in detail the principles of how the ARC system operates, what materials should be used, what components make up the system and how they are interconnected. The relevant equations regarding how to design the system for a certain response are developed and defined, and the most important aspects determining the speed of actuation of the systems are analyzed. Thus, this study serves as the general reference material for all of the fundamental principles behind the ARC idea. Finally, we present a step-by-step guide to how a fast reactor fuel subassembly with an ARC system installed would be manufactured, using a full 3D-CAD model. For an ARC installation in a 1000 MWth sodium-cooled oxide-fueled fast reactor core, the system constitutes a relatively minor adjustment to a typical fuel assembly, increasing its total axial extent by ∼5–10% and the total primary coolant pressure drop by ∼1%. The main finding of this study is that it is possible to design, manufacture (using existing methods) and implement ARC systems in the fuel assemblies of fast reactor cores to provide inherent safety in all anticipated unprotected transients with only a modest increase in the length of the assembly and the pressure drop across the core.

General Adjustment Influence Factor of Malaysian Construction Expatriates Executives Abroad

Directory of Open Access Journals (Sweden)

Zainol Halmi

2016-01-01

Full Text Available The success of Malaysian construction companies creates an opportunity to explore abroad. Past studies have shown that the difficulty of expatriates in adjusting to a new environment is the main aspect that leads to failure of assignments. The success in implementing an overseas assignment does not solely depend on an expatriate’s technical expertise. The adjustment issues such as the interaction with the host nationals, and adaptability to the host country’s culture also exert influence on the assignment. The research was conducted to identify the influence of executive expatriate general adjustment on assignment in host countries. The objective of the study was to identify adjustment influence factors relating to general adjustment abroad. Questionnaires were sent to Malaysian expatriate executives. Sixty four Malaysian expatriate executives from Malaysian construction companies overseas were involved in this study. The findings show interaction, social and living environment influences their adjustment during expatriation. Pre-departure training preparation aspects for expatriates is a good step before their departure to host countries.

C-reactive protein, insulin resistance and risk of cardiovascular disease: a population-based study

DEFF Research Database (Denmark)

Hansen, T.W.; Olsen, M.H.; Rasmussen, S.

2008-01-01

BACKGROUND: C-reactive protein (CRP), a marker of inflammation, and insulin resistance (IR), a metabolic disorder, are closely related. CRP and IR have both been identified as significant risk factors of cardiovascular disease (CVD) after adjustment for conventional CVD risk factors...

High-sensitivity C-reactive protein and risk of sepsis.

Directory of Open Access Journals (Sweden)

Henry E Wang

Full Text Available Conventional C-reactive protein assays have been used to detect or guide the treatment of acute sepsis. The objective of this study was to determine the association between elevated baseline high-sensitivity C-reactive protein (hsCRP and the risk of future sepsis events.We studied data from 30,239 community dwelling, black and white individuals, age ≥45 years old enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS cohort. Baseline hsCRP and participant characteristics were determined at the start of the study. We identified sepsis events through review of hospital records. Elevated hsCRP was defined as values >3.0 mg/L. Using Cox regression, we determined the association between elevated hsCRP and first sepsis event, adjusting for sociodemographic factors (age, sex, race, region, education, income, health behaviors (tobacco and alcohol use, chronic medical conditions (coronary artery disease, diabetes, dyslipidemia, hypertension, chronic kidney disease, chronic lung disease and statin use.Over the mean observation time of 5.7 years (IQR 4.5-7.1, 974 individuals experienced a sepsis event, and 11,447 (37.9% had elevated baseline hsCRP (>3.0 mg/L. Elevated baseline hsCRP was independently associated with subsequent sepsis (adjusted HR 1.56; 95% CI 1.36-1.79, adjusted for sociodemographics, health behaviors, chronic medical conditions and statin use.Elevated baseline hsCRP was associated with increased risk of future sepsis events. hsCRP may help to identify individuals at increased risk for sepsis.

Impact of Anemia on Platelet Reactivity and Ischemic and Bleeding Risk: From the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents Study.

Science.gov (United States)

Giustino, Gennaro; Kirtane, Ajay J; Baber, Usman; Généreux, Philippe; Witzenbichler, Bernhard; Neumann, Franz-Josef; Weisz, Giora; Maehara, Akiko; Rinaldi, Michael J; Metzger, Christopher; Henry, Timothy D; Cox, David A; Duffy, Peter L; Mazzaferri, Ernest L; Brodie, Bruce R; Stuckey, Thomas D; Gurbel, Paul A; Dangas, George D; Francese, Dominic P; Ozan, Ozgu; Mehran, Roxana; Stone, Gregg W

2016-06-15

Anemic patients remain at increased risk of ischemic and bleeding events. Whether the effects of hemoglobin levels on thrombotic and bleeding risk are independent of platelet reactivity on clopidogrel, however, remains unknown. Patients from the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents study were categorized by the presence of anemia at baseline, defined according the World Health Organization criteria. Platelet reactivity was measured with VerifyNow assay; high platelet reactivity (HPR) on clopidogrel was defined as platelet reactive units value >208. Of 8,413 patients included in the study cohort, 1,816 (21.6%) had anemia. HPR was more prevalent in patients with anemia (58.3% vs 38.4%; p <0.001), an association that persisted after multivariate adjustment (adjusted odds ratio: 2.04; 95% confidence interval [CI]: 1.82 to 2.29; p <0.0001). Patients with anemia had higher 2-year rates of major adverse cardiac events (9.5% vs 5.6%; p <0.0001), major bleeding (11.8% vs 7.7%; p <0.0001), and all-cause mortality (4.0% vs 1.4%; p <0.0001); however, after adjustment for baseline clinical confounders, including HPR, anemia was no longer significantly associated with major adverse cardiac events but was still independently associated with all-cause mortality (adjusted HR 1.61, 95% CI 1.23 to 2.12; p <0.0001) and major bleeding (adjusted HR 1.42, 95% CI 1.20 to 1.68; p <0.0001). The effect of HPR on clinical outcomes was uniform according to anemia status, without evidence of interaction. In conclusion, anemia independently correlated with HPR. After percutaneous coronary intervention with drug-eluting stents, anemia at baseline was significantly associated with higher 2-year hemorrhagic and mortality risk; conversely, its association with ischemic risk was attenuated after multivariate adjustment, including HPR. Copyright © 2016 Elsevier Inc. All rights reserved.

Improved Conjugate Gradient Bundle Adjustment of Dunhuang Wall Painting Images

Science.gov (United States)

Hu, K.; Huang, X.; You, H.

2017-09-01

Bundle adjustment with additional parameters is identified as a critical step for precise orthoimage generation and 3D reconstruction of Dunhuang wall paintings. Due to the introduction of self-calibration parameters and quasi-planar constraints, the structure of coefficient matrix of the reduced normal equation is banded-bordered, making the solving process of bundle adjustment complex. In this paper, Conjugate Gradient Bundle Adjustment (CGBA) method is deduced by calculus of variations. A preconditioning method based on improved incomplete Cholesky factorization is adopt to reduce the condition number of coefficient matrix, as well as to accelerate the iteration rate of CGBA. Both theoretical analysis and experimental results comparison with conventional method indicate that, the proposed method can effectively conquer the ill-conditioned problem of normal equation and improve the calculation efficiency of bundle adjustment with additional parameters considerably, while maintaining the actual accuracy.

Diagnostic properties of C-reactive protein for detecting pneumonia in children

NARCIS (Netherlands)

Koster, M.J.; Broekhuizen, B.D.L.; Minnaard, M.C.; Balemans, W.A.; Hopstaken, R.M.; de Jong, P.A.; Verheij, Th.J.M.

BACKGROUND: The diagnostic value of C-reactive protein (CRP) level for pneumonia in children is unknown. As a first step in the assessment of the value of CRP, a diagnostic study was performed in children at an emergency department (ED). METHODS: In this cross-sectional study, data were

An accurate autonomous islanding microgrid reactive power, imbalance power and harmonic power sharing scheme

DEFF Research Database (Denmark)

He, Jinwei; Li, Yun Wei; Blaabjerg, Frede

2013-01-01

To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through adaptive virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power or harmonic power is added to the conventional real power...

Reactive Balance in Individuals With Chronic Stroke: Biomechanical Factors Related to Perturbation-Induced Backward Falling.

Science.gov (United States)

Salot, Pooja; Patel, Prakruti; Bhatt, Tanvi

2016-03-01

An effective compensatory stepping response is the first line of defense for preventing a fall during sudden large external perturbations. The biomechanical factors that contribute to heightened fall risk in survivors of stroke, however, are not clearly understood. It is known that impending sensorimotor and balance deficits poststroke predispose these individuals to a risk of fall during sudden external perturbations. The purpose of this study was to examine the mechanism of fall risk in survivors of chronic stroke when exposed to sudden, slip-like forward perturbations in stance. This was a cross-sectional study. Fourteen individuals with stroke, 14 age-matched controls (AC group), and 14 young controls (YC group) were exposed to large-magnitude forward stance perturbations. Postural stability was computed as center of mass (COM) position (XCOM/BOS) and velocity (ẊCOM/BOS) relative to the base of support (BOS) at first step lift-off (LO) and touch-down (TD) and at second step TD. Limb support was quantified as vertical hip descent (Zhip) from baseline after perturbation onset. All participants showed a backward balance loss, with 71% of the stroke group experiencing a fall compared with no falls in the control groups (AC and YC groups). At first step LO, no between-group differences in XCOM/BOS and ẊCOM/BOS were noted. At first step TD, however, the stroke group had a significantly posterior XCOM/BOS and backward ẊCOM/BOS compared with the control groups. At second step TD, individuals with stroke were still more unstable (more posterior XCOM/BOS and backward ẊCOM/BOS) compared with the AC group. Individuals with stroke also showed greater peak Zhip compared with the control groups. Furthermore, the stroke group took a larger number of steps with shorter step length and delayed step initiation compared with the control groups. Although the study highlights the reactive balance deficits increasing fall risk in survivors of stroke compared with healthy

The reactivity meter and core reactivity

International Nuclear Information System (INIS)

Siltanen, P.

1999-01-01

This paper discussed in depth the point kinetic equations and the characteristics of the point kinetic reactivity meter, particularly for large negative reactivities. From a given input signal representing the neutron flux seen by a detector, the meter computes a value of reactivity in dollars (ρ/β), based on inverse point kinetics. The prompt jump point of view is emphasised. (Author)

Reactivity calculation using the Euler–Maclaurin formula

International Nuclear Information System (INIS)

Suescún-Díaz, Daniel; Rodríguez-Sarasty, Jesús A.; Figueroa-Jiménez, Jorge H.

2013-01-01

Highlights: ► Euler–Maclaurin formula has high precision and low computational cost. ► This method can be implemented in reactivity meters with time step of up to 0.1 s. ► This approach has not limitation of the nuclear power form. - Abstract: We develop an approximation method based on the Euler–Maclaurin formula for numerically solving the integral of the inverse point kinetic equation for nuclear reactor power. Due to its greater precision, this method requires fewer history points than other methods based on the nuclear power history. The approximation is validated with different forms of the nuclear power and with different time step calculations. Results suggest that this method, though easier to implement, has a better precision and lower computational costs than other methods that require the nuclear power history

IMPROVED CONJUGATE GRADIENT BUNDLE ADJUSTMENT OF DUNHUANG WALL PAINTING IMAGES

Directory of Open Access Journals (Sweden)

K. Hu

2017-09-01

Full Text Available Bundle adjustment with additional parameters is identified as a critical step for precise orthoimage generation and 3D reconstruction of Dunhuang wall paintings. Due to the introduction of self-calibration parameters and quasi-planar constraints, the structure of coefficient matrix of the reduced normal equation is banded-bordered, making the solving process of bundle adjustment complex. In this paper, Conjugate Gradient Bundle Adjustment (CGBA method is deduced by calculus of variations. A preconditioning method based on improved incomplete Cholesky factorization is adopt to reduce the condition number of coefficient matrix, as well as to accelerate the iteration rate of CGBA. Both theoretical analysis and experimental results comparison with conventional method indicate that, the proposed method can effectively conquer the ill-conditioned problem of normal equation and improve the calculation efficiency of bundle adjustment with additional parameters considerably, while maintaining the actual accuracy.

In utero cortisol and testosterone exposure and fear reactivity in infancy.

Science.gov (United States)

Bergman, Kristin; Glover, Vivette; Sarkar, Pampa; Abbott, Dave H; O'Connor, Thomas G

2010-03-01

Fetal programming is emerging as a major conceptual model for understanding developmental origins of health and disease, including behavioral outcomes. As part of a larger study of prenatal stress and child development, we examined the association between prenatal hormone exposure and fear reactivity, a temperament dimension that is a predictor of long-term behavioral adjustment. Amniotic fluid was collected from a sample of women undergoing clinically indicated amniocentesis for later analysis of cortisol and testosterone. Children with normal birth outcomes were recalled for follow-up assessment at 17 months, at which time we administered an observational assessment of temperament (lab-TAB; n=108). Information on pregnancy and obstetric outcome was included as covariates. Results indicated that there was a significant association between prenatal testosterone and observed fear reactivity in boys (r(53)=0.34, p=0.01); no significant effect was found in girls (r(54)=-0.07, ns); the effect remained when obstetric, psychosocial, and parental anxiety were controlled for. There was not a significant association between fetal cortisol exposure and fear reactivity. The prediction from in utero testosterone exposure to fear reactivity in boys extends prior research on prenatal testosterone and may represent an association with a general predisposition to greater arousal and reactivity. Copyright 2010 Elsevier Inc. All rights reserved.

Improvement of COD and TOC reactive dyes in textile wastewater by ...

African Journals Online (AJOL)

STORAGESEVER

2009-07-06

Jul 6, 2009 ... This study was designed to investigate the removal of reactive dyes, Samofix Red V-RBL and Samofix. Green V-G from wastewater using a two step Al (III) coagulation/activated carbon adsorption method. ... (90%) of chemical oxygen demand (COD), total organic carbon (TOC) ..... a liquid to a solid surface.

On the Pricing of Step-Up Bonds in the European Telecom Sector

DEFF Research Database (Denmark)

Lando, David; Mortensen, Allan

This paper investigates the pricing of step-up bonds, i.e. corporatebonds with provisions stating that the coupon payments increase as thecredit rating level of the issuer declines. To assess the risk-neutral ratingtransition probabilities necessary to price these bonds, we introduce...... a newcalibration method within the reduced-form rating-based model of Jarrow,Lando, and Turnbull (1997). We also treat split ratings and adjust forrating outlook. Step-up bonds have been issued in large amounts in theEuropean telecom sector, and we find that, through most of the sample,step-up bonds issued...

Efficient integration of stiff kinetics with phase change detection for reactive reservoir processes

DEFF Research Database (Denmark)

Kristensen, Morten Rode; Gerritsen, Margot G.; Thomsen, Per Grove

2007-01-01

We propose the use of implicit one-step Explicit Singly Diagonal Implicit Runge-Kutta (ESDIRK) methods for integration of the stiff kinetics in reactive, compositional and thermal processes that are solved using operator-splitting type approaches. To facilitate the algorithmic development we...

Multivariate statistical analysis of a multi-step industrial processes

DEFF Research Database (Denmark)

Reinikainen, S.P.; Høskuldsson, Agnar

2007-01-01

Monitoring and quality control of industrial processes often produce information on how the data have been obtained. In batch processes, for instance, the process is carried out in stages; some process or control parameters are set at each stage. However, the obtained data might not be utilized...... efficiently, even if this information may reveal significant knowledge about process dynamics or ongoing phenomena. When studying the process data, it may be important to analyse the data in the light of the physical or time-wise development of each process step. In this paper, a unified approach to analyse...... multivariate multi-step processes, where results from each step are used to evaluate future results, is presented. The methods presented are based on Priority PLS Regression. The basic idea is to compute the weights in the regression analysis for given steps, but adjust all data by the resulting score vectors...

A Three-Step Atomic Layer Deposition Process for SiN x Using Si2Cl6, CH3NH2, and N2 Plasma.

Science.gov (United States)

Ovanesyan, Rafaiel A; Hausmann, Dennis M; Agarwal, Sumit

2018-06-06

We report a novel three-step SiN x atomic layer deposition (ALD) process using Si 2 Cl 6 , CH 3 NH 2 , and N 2 plasma. In a two-step process, nonhydrogenated chlorosilanes such as Si 2 Cl 6 with N 2 plasmas lead to poor-quality SiN x films that oxidize rapidly. The intermediate CH 3 NH 2 step was therefore introduced in the ALD cycle to replace the NH 3 plasma step with a N 2 plasma, while using Si 2 Cl 6 as the Si precursor. This three-step process lowers the atomic H content and improves the film conformality on high-aspect-ratio nanostructures as Si-N-Si bonds are formed during a thermal CH 3 NH 2 step in addition to the N 2 plasma step. During ALD, the reactive surface sites were monitored using in situ surface infrared spectroscopy. Our infrared spectra show that, on the post-N 2 plasma-treated SiN x surface, Si 2 Cl 6 reacts primarily with the surface -NH 2 species to form surface -SiCl x ( x = 1, 2, or 3) bonds, which are the reactive sites during the CH 3 NH 2 cycle. In the N 2 plasma step, reactive -NH 2 surface species are created because of the surface H available from the -CH 3 groups. At 400 °C, the SiN x films have a growth per cycle of ∼0.9 Å with ∼12 atomic percent H. The films grown on high-aspect-ratio nanostructures have a conformality of ∼90%.

Evaluation of five strategies to limit the impact of fouling in permeable reactive barriers

International Nuclear Information System (INIS)

Li Lin; Benson, Craig H.

2010-01-01

Ground water flow and geochemical reactive transport models were used to assess the effectiveness of five strategies used to limit fouling and to enhance the long-term hydraulic behavior of continuous-wall permeable reactive barriers (PRBs) employing granular zero valent iron (ZVI). The flow model accounted for geological heterogeneity and the reactive transport model included a geochemical algorithm for simulating iron corrosion and mineral precipitation reactions that have been observed in ZVI PRBs. The five strategies that were evaluated are pea gravel equalization zones, a sacrificial pre-treatment zone, pH adjustment, large ZVI particles, and mechanical treatment. Results of simulations show that installation of pea gravel equalization zones results in flow equalization and a more uniform distribution of residence times within the PRB. Residence times within the PRB are less affected by mineral precipitation when a pre-treatment zone is employed. pH adjustment limits the total amount of hydroxide ions in ground water to reduce porosity reduction and to retain larger residence times. Larger ZVI particles reduce porosity reduction as a result of the smaller iron surface area for iron corrosion, and retain longer residence time. Mechanical treatment redistributes the porosity uniformly throughout the PRB over time, which is effective in maintaining residence time.

Ethylene dissociation on flat and stepped Ni(111): A combined STM and DFT study

DEFF Research Database (Denmark)

Vang, R.T.; Honkala, Johanna Karoliina; Dahl, S.

2006-01-01

The dissociative adsorption of ethylene (C(2)H(4)) on Ni(111) was studied by scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. The STM studies reveal that ethylene decomposes exclusively at the step edges at room temperature. However, the step edge sites...... are poisoned by the reaction products and thus only a small brim of decomposed ethylene is formed. At 500 K decomposition on the (111) facets leads to a continuous growth of carbidic islands, which nucleate along the step edges. DFT calculations were performed for several intermediate steps...... in the decomposition of ethylene on both Ni(111) and the stepped Ni(211) surface. In general the Ni(211) surface is found to have a higher reactivity than the Ni(111) surface. Furthermore, the calculations show that the influence of step edge atoms is very different for the different reaction pathways. In particular...

Uncertainty assessment in geodetic network adjustment by combining GUM and Monte-Carlo-simulations

Science.gov (United States)

Niemeier, Wolfgang; Tengen, Dieter

2017-06-01

In this article first ideas are presented to extend the classical concept of geodetic network adjustment by introducing a new method for uncertainty assessment as two-step analysis. In the first step the raw data and possible influencing factors are analyzed using uncertainty modeling according to GUM (Guidelines to the Expression of Uncertainty in Measurements). This approach is well established in metrology, but rarely adapted within Geodesy. The second step consists of Monte-Carlo-Simulations (MC-simulations) for the complete processing chain from raw input data and pre-processing to adjustment computations and quality assessment. To perform these simulations, possible realizations of raw data and the influencing factors are generated, using probability distributions for all variables and the established concept of pseudo-random number generators. Final result is a point cloud which represents the uncertainty of the estimated coordinates; a confidence region can be assigned to these point clouds, as well. This concept may replace the common concept of variance propagation and the quality assessment of adjustment parameters by using their covariance matrix. It allows a new way for uncertainty assessment in accordance with the GUM concept for uncertainty modelling and propagation. As practical example the local tie network in "Metsähovi Fundamental Station", Finland is used, where classical geodetic observations are combined with GNSS data.

Structural and reactivity models for copper oxygenases: cooperative effects and novel reactivities.

Science.gov (United States)

Serrano-Plana, Joan; Garcia-Bosch, Isaac; Company, Anna; Costas, Miquel

2015-08-18

Dioxygen is widely used in nature as oxidant. Nature itself has served as inspiration to use O2 in chemical synthesis. However, the use of dioxygen as an oxidant is not straightforward. Its triplet ground-state electronic structure makes it unreactive toward most organic substrates. In natural systems, metalloenzymes activate O2 by reducing it to more reactive peroxide (O2(2-)) or superoxide (O2(-)) forms. Over the years, the development of model systems containing transition metals has become a convenient tool for unravelling O2-activation mechanistic aspects and reproducing the oxidative activity of enzymes. Several copper-based systems have been developed within this area. Tyrosinase is a copper-based O2-activating enzyme, whose structure and reactivity have been widely studied, and that serves as a paradigm for O2 activation at a dimetal site. It contains a dicopper center in its active site, and it catalyzes the regioselective ortho-hydroxylation of phenols to catechols and further oxidation to quinones. This represents an important step in melanin biosynthesis and it is mediated by a dicopper(II) side-on peroxo intermediate species. In the present accounts, our research in the field of copper models for oxygen activation is collected. We have developed m-xylyl linked dicopper systems that mimick structural and reactivity aspects of tyrosinase. Synergistic cooperation of the two copper(I) centers results in O2 binding and formation of bis(μ-oxo)dicopper(III) cores. These in turn bind and ortho-hydroxylate phenolates via an electrophilic attack of the oxo ligand over the arene. Interestingly the bis(μ-oxo)dicopper(III) cores can also engage in ortho-hydroxylation-defluorination of deprotonated 2-fluorophenols, substrates that are well-known enzyme inhibitors. Analysis of Cu2O2 species with different binding modes show that only the bis(μ-oxo)dicopper(III) cores can mediate the reaction. Finally, the use of unsymmetric systems for oxygen activation is a field

Active and reactive power neurocontroller for grid-connected photovoltaic generation system

Directory of Open Access Journals (Sweden)

I. Abadlia

2016-03-01

Full Text Available Many researchers have contributed to the development of a firm foundation for analysis and design of control applications in grid-connected renewable energy sources. This paper presents an intelligent control algorithm fond on artificial neural networks for active and reactive power controller in grid-connected photovoltaic generation system. The system is devices into two parts in which each part contains an inverter with control algorithm. A DC/DC converter in output voltage established by control magnitude besides maximum power point tracker algorithm always finds optimal power of the PV array in use. A DC/AC hysteresis inverter designed can synchronize a sinusoidal current output with the grid voltage and accurate an independent active and reactive power control. Simulation results confirm the validation of the purpose. Neurocontroller based active and reactive power presents an efficiency control that guarantees good response to the steps changing in active and reactive power with an acceptable current/voltage synchronism. In this paper the power circuit and the control system of the presented grid-connected photovoltaic generation system is simulated and tested by MatLab/Simulink.

Photocatalytic oxidation of a reactive azo dye and evaluation of the ...

African Journals Online (AJOL)

The purpose of this study was to investigate the photocatalytic oxidation of a reactive azo dye and determine the improvement in the biodegradability when photocatalytic oxidation was used as a pretreatment step prior to biological treatment. The results obtained from the experiments adding H2O2/TiO2 show that the ...

One-step method for the production of nanofluids

Science.gov (United States)

Kostic, Milivoje [Chicago, IL; Golubovic, Mihajlo [Chicago, IL; Hull, John R [Downers Grove, IL; Choi, Stephen U. S. [Napersville, IL

2010-05-18

A one step method and system for producing nanofluids by a particle-source evaporation and deposition of the evaporant into a base fluid. The base fluid such (i.e. ethylene glycol) is placed in a rotating cylindrical drum having an adjustable heater-boat-evaporator and heat exchanger-cooler apparatus. As the drum rotates, a thin liquid layer is formed on the inside surface of the drum. A heater-boat-evaporator having an evaporant material (particle-source) placed within its boat evaporator is adjustably positioned near a portion of the rotating thin liquid layer, the evaporant material being heated thereby evaporating a portion of the evaporant material, the evaporated material absorbed by the liquid film to form nanofluid.

Reactive modification of polyesters and their blends

Science.gov (United States)

Wan, Chen

2004-12-01

the desired rheological and structural characteristics of the final products for potential applications such as low density extrusion foaming or compatibilization of immiscible polymer blends. Important modification conditions through coagents are identified and reaction mechanisms are proposed. A high MW saturated polyester, PET, can also be rheologically modified in extruders through low MW multifunctional anhydride and epoxy compounds by chain extension/branching. Several such modifiers were successfully screened in terms of their reactivity towards PET under controlled reactive extrusion conditions. A dianhydride with medium reactivity was then successfully used in a one-step reactive modification/extrusion foaming process to produce low density foams. A similar process was successfully used to produce small cell size foams from a four component system containing PET, PP and lesser amounts of a low molecular weight multifunctional epoxy compound and an acid functionalized polyolefin, the latter acting as compatibilizers.

Quasi-epitaxial barium hexaferrite thin films prepared by a topotactic reactive diffusion process

Science.gov (United States)

Meng, Siqin; Yue, Zhenxing; Zhang, Xiaozhi; Li, Longtu

2014-01-01

Quasi-epitaxial barium hexaferrite thin films (BaM) with crystallographic c-axis parallel to film normal were prepared through a topotactic reactive diffusion process using two-step solution deposition on c-plane sapphire. The two-step spin coating process involves preparing an epitaxial hematite film, coating the film with barium precursor solution and thermal annealing. The crystal orientation and magnetic anisotropy of BaM thin films were investigated by X-ray diffraction analysis, SEM observation and magnetic measurements. Hysteresis loops showed good magnetic anisotropy and high remanence ratio (RR) Mr/Ms = 0.97. The films fabricated by two-step spin coating process displayed wider rocking curve width but better magnetic anisotropy than one-step spin coating. The possible mechanism of this discrepancy is discussed in this paper.

Quasi-epitaxial barium hexaferrite thin films prepared by a topotactic reactive diffusion process

Energy Technology Data Exchange (ETDEWEB)

Meng, Siqin; Yue, Zhenxing, E-mail: yuezhx@tsinghua.edu.cn; Zhang, Xiaozhi; Li, Longtu

2014-01-30

Quasi-epitaxial barium hexaferrite thin films (BaM) with crystallographic c-axis parallel to film normal were prepared through a topotactic reactive diffusion process using two-step solution deposition on c-plane sapphire. The two-step spin coating process involves preparing an epitaxial hematite film, coating the film with barium precursor solution and thermal annealing. The crystal orientation and magnetic anisotropy of BaM thin films were investigated by X-ray diffraction analysis, SEM observation and magnetic measurements. Hysteresis loops showed good magnetic anisotropy and high remanence ratio (RR) Mr/Ms = 0.97. The films fabricated by two-step spin coating process displayed wider rocking curve width but better magnetic anisotropy than one-step spin coating. The possible mechanism of this discrepancy is discussed in this paper.

Void coefficient of reactivity calculation for AP-600 core

International Nuclear Information System (INIS)

Suparlina, L.; Budiono, T.A.; Mardha, A.; Tukiran

1998-01-01

Void coefficient of reactivity as one of reactor kinetics parameters has been carried out. The calculation was done into two steps which is cell calculation using WIMSD/4 and core calculation using Batan-2DIFF code programs with the condition of beginning of cycle with all fresh fuels elements and all control rods withdrawn. The one dimension transport program in four neutron energy groups is used to calculate the cell generation of various core materials cell has been calculated in 1/4 fuel element with cluster model and square pitch arrange. Moderator density have been reduced until 20% for the void coefficient of reactivity calculation. Macroscopic cross-section as the out put of WIMSD/4 is being used as the input at the diffusion neutron program for core calculation. The void coefficient of reactivity of the AP-600 core can be determined with regular neutron flux and adjoint in four energy groups and X-Y geometry. The results is shown that the K eff calculation value is different 5.2% from the design data

Step-to-step variability in treadmill walking: influence of rhythmic auditory cueing.

Directory of Open Access Journals (Sweden)

Philippe Terrier

Full Text Available While walking, human beings continuously adjust step length (SpL, step time (SpT, step speed (SpS = SpL/SpT and step width (SpW by integrating both feedforward and feedback mechanisms. These motor control processes result in correlations of gait parameters between consecutive strides (statistical persistence. Constraining gait with a speed cue (treadmill and/or a rhythmic auditory cue (metronome, modifies the statistical persistence to anti-persistence. The objective was to analyze whether the combined effect of treadmill and rhythmic auditory cueing (RAC modified not only statistical persistence, but also fluctuation magnitude (standard deviation, SD, and stationarity of SpL, SpT, SpS and SpW. Twenty healthy subjects performed 6 × 5 min. walking tests at various imposed speeds on a treadmill instrumented with foot-pressure sensors. Freely-chosen walking cadences were assessed during the first three trials, and then imposed accordingly in the last trials with a metronome. Fluctuation magnitude (SD of SpT, SpL, SpS and SpW was assessed, as well as NonStationarity Index (NSI, which estimates the dispersion of local means in the times series (SD of 20 local means over 10 steps. No effect of RAC on fluctuation magnitude (SD was observed. SpW was not modified by RAC, what is likely the evidence that lateral foot placement is separately regulated. Stationarity (NSI was modified by RAC in the same manner as persistent pattern: Treadmill induced low NSI in the time series of SpS, and high NSI in SpT and SpL. On the contrary, SpT, SpL and SpS exhibited low NSI under RAC condition. We used relatively short sample of consecutive strides (100 as compared to the usual number of strides required to analyze fluctuation dynamics (200 to 1000 strides. Therefore, the responsiveness of stationarity measure (NSI to cued walking opens the perspective to perform short walking tests that would be adapted to patients with a reduced gait perimeter.

Data analysis-based autonomic bandwidth adjustment in software defined multi-vendor optical transport networks.

Science.gov (United States)

Li, Yajie; Zhao, Yongli; Zhang, Jie; Yu, Xiaosong; Jing, Ruiquan

2017-11-27

Network operators generally provide dedicated lightpaths for customers to meet the demand for high-quality transmission. Considering the variation of traffic load, customers usually rent peak bandwidth that exceeds the practical average traffic requirement. In this case, bandwidth provisioning is unmetered and customers have to pay according to peak bandwidth. Supposing that network operators could keep track of traffic load and allocate bandwidth dynamically, bandwidth can be provided as a metered service and customers would pay for the bandwidth that they actually use. To achieve cost-effective bandwidth provisioning, this paper proposes an autonomic bandwidth adjustment scheme based on data analysis of traffic load. The scheme is implemented in a software defined networking (SDN) controller and is demonstrated in the field trial of multi-vendor optical transport networks. The field trial shows that the proposed scheme can track traffic load and realize autonomic bandwidth adjustment. In addition, a simulation experiment is conducted to evaluate the performance of the proposed scheme. We also investigate the impact of different parameters on autonomic bandwidth adjustment. Simulation results show that the step size and adjustment period have significant influences on bandwidth savings and packet loss. A small value of step size and adjustment period can bring more benefits by tracking traffic variation with high accuracy. For network operators, the scheme can serve as technical support of realizing bandwidth as metered service in the future.

Bio-inspired step-climbing in a hexapod robot

International Nuclear Information System (INIS)

Chou, Ya-Cheng; Yu, Wei-Shun; Huang, Ke-Jung; Lin, Pei-Chun

2012-01-01

Inspired by the observation that the cockroach changes from a tripod gait to a different gait for climbing high steps, we report on the design and implementation of a novel, fully autonomous step-climbing maneuver, which enables a RHex-style hexapod robot to reliably climb a step up to 230% higher than the length of its leg. Similar to the climbing strategy most used by cockroaches, the proposed maneuver is composed of two stages. The first stage is the ‘rearing stage,’ inclining the body so the front side of the body is raised and it is easier for the front legs to catch the top of the step, followed by the ‘rising stage,’ maneuvering the body's center of mass to the top of the step. Two infrared range sensors are installed on the front of the robot to detect the presence of the step and its orientation relative to the robot's heading, so that the robot can perform automatic gait transition, from walking to step-climbing, as well as correct its initial tilt approaching posture. An inclinometer is utilized to measure body inclination and to compute step height, thus enabling the robot to adjust its gait automatically, in real time, and to climb steps of different heights and depths successfully. The algorithm is applicable for the robot to climb various rectangular obstacles, including a narrow bar, a bar and a step (i.e. a bar of infinite width). The performance of the algorithm is evaluated experimentally, and the comparison of climbing strategies and climbing behaviors in biological and robotic systems is discussed. (paper)

On reactive suspension plasma spraying of calcium titanate

OpenAIRE

Kotlan, J. (Jiří); Pala, Z. (Zdeněk); Mušálek, R. (Radek); Ctibor, P. (Pavel)

2016-01-01

This study shows possibility of preparation of calcium titanate powder and coatings by reactive suspension plasma spraying. Suspension of mixture of calcium carbonate (CaCO3) and titanium dioxide (TiO2) powders in ethanol was fed into hybrid plasma torch with a DC-arc stabilized by a water–argon mixture (WSP-H 500). Various feeding distances and angles were used in order to optimize suspension feeding conditions. In the next step, the coatings were deposited on stainless steel substrates and ...

The Role of Emotional Responses and Physiological Reactivity in the Marital Conflict-Child Functioning Link

Science.gov (United States)

El-Sheikh, Mona

2005-01-01

Background: Children's emotional responses and physiological reactivity to conflict were examined as mediators and moderators in the associations between exposure to parental marital conflict and child adjustment and cognitive problems. Method: One hundred and eighty elementary school children participated. In response to a simulated argument,…

Lack of independent relationships between left ventricular mass and cardiovascular reactivity to physical and psychological stress in the Coronary Artery Risk Development in Young Adults (CARDIA) Study.

Science.gov (United States)

Markovitz, J H; Raczynski, J M; Lewis, C E; Flack, J; Chesney, M; Chettur, V; Hardin, J M; Johnson, E

1996-09-01

The objective of this study was to determine whether exaggerated blood pressure (BP) reactivity to stress and psychosocial characteristics are related to left ventricular mass (LVM) in a large cohort of young adults. Analyses were conducted with 3,742 participants of the CARDIA study (945 white men, 1,024 white women, 781 black men, and 992 black women), evaluated in 1990 to 1091 with echocardiographic measurement of LVM. Analyses were stratified by gender and race. The relationships of LVM/height2.7 and cardiovascular reactivity to physical and psychological stressors (treadmill exercise, cold pressor, video game, and star-tracing tasks), were examined in both univariate and multivariate analyses adjusting for baseline BP, weight, and other relevant biobehavioral variables. The relationships between LVM and several psychosocial characteristics (hostility, anger suppression, anxiety, depressive symptoms, and education) were also assessed. Systolic blood pressure (SBP) reactivity to exercise was significantly related to LVM in black and white men; LVM was 10% greater among white men with exaggerated (upper quintile) peak exercise SBP than among other white men. SBP reactivity to the cold pressor test was related to LVM in all race/gender groups, although the relationship remained significant only among white men and women in the multivariate analysis. Diastolic blood pressure (DBP) reactivity to the video game was related to LVM only among black men in adjusted analyses. After adjusting for resting BP, weight, and other covariates in linear multiple regression models, SBP reactivity to exercise explained only 3% of the variance in LVM among white men. Otherwise, reactivity to other stressors or psychosocial variables accounted for no more than 1% of the variance in LVM. It was concluded that among a cohort of young adults, blood pressure reactivity to physical and mental stressors did not add substantially to the prediction of LVM when resting BP, weight, and other

Calculation of reactivity without Lagrange interpolation; Calculo de la reactividad sin interpolacion de Lagrange

Energy Technology Data Exchange (ETDEWEB)

Suescun D, D.; Figueroa J, J. H. [Pontificia Universidad Javeriana Cali, Departamento de Ciencias Naturales y Matematicas, Calle 18 No. 118-250, Cali, Valle del Cauca (Colombia); Rodriguez R, K. C.; Villada P, J. P., E-mail: dsuescun@javerianacali.edu.co [Universidad del Valle, Departamento de Fisica, Calle 13 No. 100-00, Cali, Valle del Cauca (Colombia)

2015-09-15

A new method to solve numerically the inverse equation of punctual kinetics without using Lagrange interpolating polynomial is formulated; this method uses a polynomial approximation with N points based on a process of recurrence for simulating different forms of nuclear power. The results show a reliable accuracy. Furthermore, the method proposed here is suitable for real-time measurements of reactivity, with step sizes of calculations greater that Δt = 0.3 s; due to its precision can be used to implement a digital meter of reactivity in real time. (Author)

Simulation and study on reactivity disturbs dynamic character of HTR-10 nuclear power system

International Nuclear Information System (INIS)

Huang Xiaojin; Feng Yuankun

2002-01-01

In order to not only know 10 MW High Temperature Gas Cooled Reactor (HTR-10) nuclear power system's dynamic character more deeply but also to satisfy requirements of control system's design and analysis, the dynamic model of HTR-10 nuclear power system is established on the basis of dynamic model of HTR-10 nuclear system, which supplies turbine and generate electricity system model. Using this model, system's main variables' dynamic processes are simulated when control rod takes step reactivity disturb. The concussive progresses which is caused by reactivity disturb are analyzed. The results indicate that fuel temperature changing more slowly than nuclear power makes reactivity negative feedback not to restrain power changing, and then power concussive progress comes to being

Differentiation of Self and Dyadic Adjustment in Couple Relationships: A Dyadic Analysis Using the Actor-Partner Interdependence Model.

Science.gov (United States)

Lampis, Jessica; Cataudella, Stefania; Agus, Mirian; Busonera, Alessandra; Skowron, Elizabeth A

2018-06-10

Bowen's multigenerational theory provides an account of how the internalization of experiences within the family of origin promotes development of the ability to maintain a distinct self whilst also making intimate connections with others. Differentiated people can maintain their I-position in intimate relationships. They can remain calm in conflictual relationships, resolve relational problems effectively, and reach compromises. Fusion with others, emotional cut-off, and emotional reactivity instead are common reactions to relational stress in undifferentiated people. Emotional reactivity is the tendency to react to stressors with irrational and intense emotional arousal. Fusion with others is an excessive emotional involvement in significant relationships, whilst emotional cut-off is the tendency to manage relationship anxiety through physical and emotional distance. This study is based on Bowen's theory, starting from the assumption that dyadic adjustment can be affected both by a member's differentiation of self (actor effect) and by his or her partner's differentiation of self (partner effect). We used the Actor-Partner Interdependence Model to study the relationship between differentiation of self and dyadic adjustment in a convenience sample of 137 heterosexual Italian couples (nonindependent, dyadic data). The couples completed the Differentiation of Self Inventory and the Dyadic Adjustment Scale. Men's dyadic adjustment depended only on their personal I-position, whereas women's dyadic adjustment was affected by their personal I-position and emotional cut-off as well as by their partner's I-position and emotional cut-off. The empirical and clinical implications of the results are discussed. © 2018 Family Process Institute.

Adams-Bashforth-Moulton method with Savitzky-Golay filter to reduce reactivity fluctuations

Energy Technology Data Exchange (ETDEWEB)

Suescun-Diaz, Daniel; Rasero Causil, Diego A. [Univ. Surcolombiana, Neiva (Colombia). Dept. de Ciencias Exactas y Naturales; Figueroa-Jimenez, Jorge H. [Pontificia Universidad Javeriana Cali, Cali (Colombia). Dept. de Ciencias Naturales y Matematicas

2017-12-15

In this paper we present a new method of calculating reactivity with fluctuation reduction. First we propose the generalized predictor and corrector using the fourth order Adams-Basforth-Moulton (ABM) for the numerical solution of the point kinetic equations for the calculation of reactivity, without using the history of nuclear power. Due to the nature of point kinetic equations, we use modifiers of the different predictors to increase precision in the approximation obtained. Secondly, we use the filter known as Savitzky-Golay (SG), which permits the reduction of the fluctuation in reactivity. It is known that the SG filter smoothing without diminishing the value of the nuclear power, irrespective of its form; this guarantees the reduction of Gaussian random noise levels, which is distributed around the average value of the nuclear power of up to σ = 0.1, with a time step h = 0.01 s. This formulation uses the Gram polynomial approximation, with a degree d = 2 the results show better values in the maximum difference in reactivity in comparison with that reported in literature.

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

2011-05-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

SPAR-H Step-by-Step Guidance

International Nuclear Information System (INIS)

Galyean, W.J.; Whaley, A.M.; Kelly, D.L.; Boring, R.L.

2011-01-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

2012-06-01

Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

Transcriptome wide annotation of eukaryotic RNase III reactivity and degradation signals.

Directory of Open Access Journals (Sweden)

Jules Gagnon

2015-02-01

Full Text Available Detection and validation of the RNA degradation signals controlling transcriptome stability are essential steps for understanding how cells regulate gene expression. Here we present complete genomic and biochemical annotations of the signals required for RNA degradation by the dsRNA specific ribonuclease III (Rnt1p and examine its impact on transcriptome expression. Rnt1p cleavage signals are randomly distributed in the yeast genome, and encompass a wide variety of sequences, indicating that transcriptome stability is not determined by the recurrence of a fixed cleavage motif. Instead, RNA reactivity is defined by the sequence and structural context in which the cleavage sites are located. Reactive signals are often associated with transiently expressed genes, and their impact on RNA expression is linked to growth conditions. Together, the data suggest that Rnt1p reactivity is triggered by malleable RNA degradation signals that permit dynamic response to changes in growth conditions.

Transcriptome Wide Annotation of Eukaryotic RNase III Reactivity and Degradation Signals

Science.gov (United States)

Gagnon, Jules; Lavoie, Mathieu; Catala, Mathieu; Malenfant, Francis; Elela, Sherif Abou

2015-01-01

Detection and validation of the RNA degradation signals controlling transcriptome stability are essential steps for understanding how cells regulate gene expression. Here we present complete genomic and biochemical annotations of the signals required for RNA degradation by the dsRNA specific ribonuclease III (Rnt1p) and examine its impact on transcriptome expression. Rnt1p cleavage signals are randomly distributed in the yeast genome, and encompass a wide variety of sequences, indicating that transcriptome stability is not determined by the recurrence of a fixed cleavage motif. Instead, RNA reactivity is defined by the sequence and structural context in which the cleavage sites are located. Reactive signals are often associated with transiently expressed genes, and their impact on RNA expression is linked to growth conditions. Together, the data suggest that Rnt1p reactivity is triggered by malleable RNA degradation signals that permit dynamic response to changes in growth conditions. PMID:25680180

Multi-Step Deep Reactive Ion Etching Fabrication Process for Silicon-Based Terahertz Components

Science.gov (United States)

Jung-Kubiak, Cecile (Inventor); Reck, Theodore (Inventor); Chattopadhyay, Goutam (Inventor); Perez, Jose Vicente Siles (Inventor); Lin, Robert H. (Inventor); Mehdi, Imran (Inventor); Lee, Choonsup (Inventor); Cooper, Ken B. (Inventor); Peralta, Alejandro (Inventor)

2016-01-01

A multi-step silicon etching process has been developed to fabricate silicon-based terahertz (THz) waveguide components. This technique provides precise dimensional control across multiple etch depths with batch processing capabilities. Nonlinear and passive components such as mixers and multipliers waveguides, hybrids, OMTs and twists have been fabricated and integrated into a small silicon package. This fabrication technique enables a wafer-stacking architecture to provide ultra-compact multi-pixel receiver front-ends in the THz range.

Intrinsic char reactivity of plastic waste (PET) during CO2 gasification

International Nuclear Information System (INIS)

Gil, M.V.; Fermoso, J.; Pevida, C.; Pis, J.J.; Rubiera, F.

2010-01-01

Char reactivity has a strong influence on the gasification process, since char gasification is the slowest step in the process. A sample of waste PET was devolatilised in a vertical quartz reactor and the resulting char was partially gasified under a CO 2 atmosphere at 925 C in order to obtain samples with different degrees of conversion. The reactivity of the char in CO 2 was determined by isothermal thermogravimetric analysis at different temperatures in a kinetically controlled regime and its reactive behaviour was evaluated by means of the random pore model (RPM). The texture of the char was characterised by means of N 2 and CO 2 adsorption isotherms. The results did not reveal any variation in char reactivity during conversion, whereas the micropore surface area was affected during the gasification process. It was found that the intrinsic reaction rate of the char can be satisfactorily calculated by normalizing the reaction rate by the narrow micropore surface area calculated from the CO 2 adsorption isotherms. It can be concluded therefore that the surface area available for the gasification process is the area corresponding to the narrow microporosity. (author)

Small Sample Reactivity Measurements in the RRR/SEG Facility: Reanalysis using TRIPOLI-4

Energy Technology Data Exchange (ETDEWEB)

Hummel, Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Palmiotti, Guiseppe [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-08-01

This work involved reanalyzing the RRR/SEG integral experiments performed at the Rossendorf facility in Germany throughout the 1970s and 80s. These small sample reactivity worth measurements were carried out using the pile oscillator technique for many different fission products, structural materials, and standards. The coupled fast-thermal system was designed such that the measurements would provide insight into elemental data, specifically the competing effects between neutron capture and scatter. Comparing the measured to calculated reactivity values can then provide adjustment criteria to ultimately improve nuclear data for fast reactor designs. Due to the extremely small reactivity effects measured (typically less than 1 pcm) and the specific heterogeneity of the core, the tool chosen for this analysis was TRIPOLI-4. This code allows for high fidelity 3-dimensional geometric modeling, and the most recent, unreleased version, is capable of exact perturbation theory.

Application of a Virtual Reactivity Feedback Control Loop in Non-Nuclear Testing of a Fast Spectrum Reactor

International Nuclear Information System (INIS)

Bragg-Sitton, Shannon M.; Forsbacka, Matthew

2004-01-01

For a compact, fast-spectrum reactor, reactivity feedback is dominated by core deformation at elevated temperature. Given the use of accurate deformation measurement techniques, it is possible to simulate nuclear feedback in non-nuclear electrically heated reactor tests. Implementation of simulated reactivity feedback in response to measured deflection is being tested at the Nasa Marshall Space Flight Center Early Flight Fission Test Facility (EFF-TF). During tests of the SAFE-100 reactor prototype, core deflection was monitored using a high resolution camera. 'Virtual' reactivity feedback was accomplished by applying the results of Monte Carlo calculations (MCNPX) to core deflection measurements; the computational analysis was used to establish the reactivity worth of various core deformations. The power delivered to the SAFE-100 prototype was then adjusted accordingly via kinetics calculations. The work presented in this paper will demonstrate virtual reactivity feedback as core power was increased from 1 kWt to 10 kWt, held approximately constant at 10 kWt, and then allowed to decrease based on the negative thermal reactivity coefficient. (authors)

Insights into the reactivation of cobalamin-dependent methionine synthase

Energy Technology Data Exchange (ETDEWEB)

Koutmos, Markos; Datta, Supratim; Pattridge, Katherine A.; Smith, Janet L.; Matthews, Rowena G.; (Michigan)

2009-12-10

Cobalamin-dependent methionine synthase (MetH) is a modular protein that catalyzes the transfer of a methyl group from methyltetrahydrofolate to homocysteine to produce methionine and tetrahydrofolate. The cobalamin cofactor, which serves as both acceptor and donor of the methyl group, is oxidized once every {approx}2,000 catalytic cycles and must be reactivated by the uptake of an electron from reduced flavodoxin and a methyl group from S-adenosyl-L-methionine (AdoMet). Previous structures of a C-terminal fragment of MetH (MetH{sup CT}) revealed a reactivation conformation that juxtaposes the cobalamin- and AdoMet-binding domains. Here we describe 2 structures of a disulfide stabilized MetH{sup CT} ({sub s-s}MetH{sup CT}) that offer further insight into the reactivation of MetH. The structure of {sub s-s}MetH{sup CT} with cob(II)alamin and S-adenosyl-L-homocysteine represents the enzyme in the reactivation step preceding electron transfer from flavodoxin. The structure supports earlier suggestions that the enzyme acts to lower the reduction potential of the Co(II)/Co(I) couple by elongating the bond between the cobalt and its upper axial water ligand, effectively making the cobalt 4-coordinate, and illuminates the role of Tyr-1139 in the stabilization of this 4-coordinate state. The structure of {sub s-s}MetH{sub CT} with aquocobalamin may represent a transient state at the end of reactivation as the newly remethylated 5-coordinate methylcobalamin returns to the 6-coordinate state, triggering the rearrangement to a catalytic conformation.

[Reactive anxiety crisis and chronic adjustment disorder: a unique case of work injury and suspected occupational disease].

Science.gov (United States)

Taino, Giuseppe; Pizzuto, Cristina; Pezzuto, Cristina; Pucci, Ennio; Imbriani, Marcello

2014-01-01

The present study aims to describe a case of work injury and occupational disease which is unique for the type of disease diagnosed, conditions of onset and mode of management by INAIL (Italian National Institute of Insurance for Injuries at Work and Occupational Diseases). A worker, after a verbal animated dispute with some collegues and superiors, had an acute psychiatric agitation attack and went to the nearest emergency room, where he was subjected to clinical exams. No neuropsychiatric alteration was found, but the physicians diagnosed an anxiety crisis reactive to the work environment. Consequently, the medical certificate for work injury was edited and sent to INAIL. The worker has been off work for 110 days because of a anxious and depressive syndrome, due to the verbal conflict. In a later assessment, INAIL recognized only the first 30 days of the employee's time off as injury at work, while judging the following period off work as related to affectivity disturbance due to common disease, not related to work environment. The following year, "anxious-depressive syndrome" is worsened and attributed by the same worker to the recurrence of acts of persecution and discrimination against him at work. For this reason he applied for recognition of occupational disease diagnosed as "Chronic Adjustment Disorder with prolonged depressive reaction and somatic anxiety, which developed into a protracted conflict marked the employment situation". INAIL rejected that request, but in the same year the employee has submitted the complaint for "mobbing". Even this request was rejected. Literature shows many examples of traumatic events during working activities which cause psychiatric disturbances. These events include industrial disasters, explosions, transport and mining accidents, accidents in psychiatric units with high risks of assaults, armed conflicts, war, assault and sexual assault, natural disasters. Victims show symptoms of acute stress disorder (ASD) or post

ITP Adjuster 1.0: A New Utility Program to Adjust Charges in the Topology Files Generated by the PRODRG Server

OpenAIRE

Medeiros, Diogo de Jesus; Cortopassi, Wilian Augusto; Costa França, Tanos Celmar; Pimentel, André Silva

2013-01-01

The suitable computation of accurate atomic charges for the GROMACS topology *.itp files of small molecules, generated in the PRODRG server, has been a tricky task nowadays because it does not calculate atomic charges using an ab initio method. Usually additional steps of structure optimization and charges calculation, followed by a tedious manual replacement of atomic charges in the *.itp file, are needed. In order to assist this task, we report here the ITP Adjuster 1.0, a utility program d...

Reactive Kripke semantics

CERN Document Server

Gabbay, Dov M

2013-01-01

This text offers an extension to the traditional Kripke semantics for non-classical logics by adding the notion of reactivity. Reactive Kripke models change their accessibility relation as we progress in the evaluation process of formulas in the model. This feature makes the reactive Kripke semantics strictly stronger and more applicable than the traditional one. Here we investigate the properties and axiomatisations of this new and most effective semantics, and we offer a wide landscape of applications of the idea of reactivity. Applied topics include reactive automata, reactive grammars, rea

Reactivity loss validation of high burn-up PWR fuels with pile-oscillation experiments in MINERVE

Energy Technology Data Exchange (ETDEWEB)

Leconte, P.; Vaglio-Gaudard, C.; Eschbach, R.; Di-Salvo, J.; Antony, M.; Pepino, A. [CEA, DEN, DER, Cadarache, F-13108 Saint-Paul-Lez-Durance (France)

2012-07-01

The ALIX experimental program relies on the experimental validation of the spent fuel inventory, by chemical analysis of samples irradiated in a PWR between 5 and 7 cycles, and also on the experimental validation of the spent fuel reactivity loss with bum-up, obtained by pile-oscillation measurements in the MINERVE reactor. These latter experiments provide an overall validation of both the fuel inventory and of the nuclear data responsible for the reactivity loss. This program offers also unique experimental data for fuels with a burn-up reaching 85 GWd/t, as spent fuels in French PWRs never exceeds 70 GWd/t up to now. The analysis of these experiments is done in two steps with the APOLLO2/SHEM-MOC/CEA2005v4 package. In the first one, the fuel inventory of each sample is obtained by assembly calculations. The calculation route consists in the self-shielding of cross sections on the 281 energy group SHEM mesh, followed by the flux calculation by the Method Of Characteristics in a 2D-exact heterogeneous geometry of the assembly, and finally a depletion calculation by an iterative resolution of the Bateman equations. In the second step, the fuel inventory is used in the analysis of pile-oscillation experiments in which the reactivity of the ALIX spent fuel samples is compared to the reactivity of fresh fuel samples. The comparison between Experiment and Calculation shows satisfactory results with the JEFF3.1.1 library which predicts the reactivity loss within 2% for burn-up of {approx}75 GWd/t and within 4% for burn-up of {approx}85 GWd/t. (authors)

Study of the IPR-R1 dynamics by means of reactivity pseudo-aleatory excitations

International Nuclear Information System (INIS)

Roedel, G.

1983-01-01

Aiming to demonstrate the feasibility of using the reactor noise neutronic analysis tecniques a dynamic model was developed for the IPR-R1 reactor at CDTN. This model allows reactivity feedback, due to the variations of fuel and coolant temperature. The system was excited by the variations of reactivity modulated by a pseudo aleatory binary sequence and its answer was measured by means of the fluctuactions dround the stationary power. The model developed and the technique used was tested, and the values of the system parameters obtained from the adjustment of the theoretical and experimental transfer function were compared to another, obtained from independent process. (E.G.) [pt

TRANC - a novel fast-response converter to measure total reactive atmospheric nitrogen

Science.gov (United States)

Marx, O.; Brümmer, C.; Ammann, C.; Wolff, V.; Freibauer, A.

2012-05-01

The input and loss of plant available nitrogen (reactive nitrogen: Nr) from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter), which offers the opportunity to quantify the sum of all airborne reactive nitrogen compounds (∑Nr) in high time resolution. The basic concept of the TRANC is the full conversion of all Nr to nitrogen monoxide (NO) within two reaction steps. Initially, reduced Nr compounds are being oxidised, and oxidised Nr compounds are thermally converted to lower oxidation states. Particulate Nr is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher nitrogen oxides or those generated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD) for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3-, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in ∑Nr concentrations and also matches the sum of all individual Nr compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal and catalytic

A novel instrumented multipeg running wheel system, Step-Wheel, for monitoring and controlling complex sequential stepping in mice.

Science.gov (United States)

Kitsukawa, Takashi; Nagata, Masatoshi; Yanagihara, Dai; Tomioka, Ryohei; Utsumi, Hideko; Kubota, Yasuo; Yagi, Takeshi; Graybiel, Ann M; Yamamori, Tetsuo

2011-07-01

Motor control is critical in daily life as well as in artistic and athletic performance and thus is the subject of intense interest in neuroscience. Mouse models of movement disorders have proven valuable for many aspects of investigation, but adequate methods for analyzing complex motor control in mouse models have not been fully established. Here, we report the development of a novel running-wheel system that can be used to evoke simple and complex stepping patterns in mice. The stepping patterns are controlled by spatially organized pegs, which serve as footholds that can be arranged in adjustable, ladder-like configurations. The mice run as they drink water from a spout, providing reward, while the wheel turns at a constant speed. The stepping patterns of the mice can thus be controlled not only spatially, but also temporally. A voltage sensor to detect paw touches is attached to each peg, allowing precise registration of footfalls. We show that this device can be used to analyze patterns of complex motor coordination in mice. We further demonstrate that it is possible to measure patterns of neural activity with chronically implanted tetrodes as the mice engage in vigorous running bouts. We suggest that this instrumented multipeg running wheel (which we name the Step-Wheel System) can serve as an important tool in analyzing motor control and motor learning in mice.

Reactive power and voltage control strategy based on dynamic and adaptive segment for DG inverter

Science.gov (United States)

Zhai, Jianwei; Lin, Xiaoming; Zhang, Yongjun

2018-03-01

The inverter of distributed generation (DG) can support reactive power to help solve the problem of out-of-limit voltage in active distribution network (ADN). Therefore, a reactive voltage control strategy based on dynamic and adaptive segment for DG inverter is put forward to actively control voltage in this paper. The proposed strategy adjusts the segmented voltage threshold of Q(U) droop curve dynamically and adaptively according to the voltage of grid-connected point and the power direction of adjacent downstream line. And then the reactive power reference of DG inverter can be got through modified Q(U) control strategy. The reactive power of inverter is controlled to trace the reference value. The proposed control strategy can not only control the local voltage of grid-connected point but also help to maintain voltage within qualified range considering the terminal voltage of distribution feeder and the reactive support for adjacent downstream DG. The scheme using the proposed strategy is compared with the scheme without the reactive support of DG inverter and the scheme using the Q(U) control strategy with constant segmented voltage threshold. The simulation results suggest that the proposed method has a significant improvement on solving the problem of out-of-limit voltage, restraining voltage variation and improving voltage quality.

Reactive flow modeling of initial density effect on divergence JB-9014 detonation driving

Science.gov (United States)

Yu, Xin; Huang, Kuibang; Zheng, Miao

2016-06-01

A serious of experiments were designed and the results were represented in this paper, in which 2mm thickness cooper shells were impacted by explosives named JB-9014 with different densities, and the surface velocities of the OFHC shells were measured. The comparison of experimental data shows the free surface velocity of the OFHC shell increase with the IHE density. Numerical modeling, which occupied phenomenological reactive flow rate model using the two-dimensional Lagrange hydrodynamic code, were carried out to simulate the above experiments, and empirical adjustments on detonation velocity and pressure and Pier Tang's adjustments on EOS of detonation products were both introduced in our numerical simulation work. The computational results agree well with that of experiments, and the numerical results with original parameters of products and the adjusted ones of JB-9014 could describe the density effect distinctly.

Algorithms of GPU-enabled reactive force field (ReaxFF) molecular dynamics.

Science.gov (United States)

Zheng, Mo; Li, Xiaoxia; Guo, Li

2013-04-01

Reactive force field (ReaxFF), a recent and novel bond order potential, allows for reactive molecular dynamics (ReaxFF MD) simulations for modeling larger and more complex molecular systems involving chemical reactions when compared with computation intensive quantum mechanical methods. However, ReaxFF MD can be approximately 10-50 times slower than classical MD due to its explicit modeling of bond forming and breaking, the dynamic charge equilibration at each time-step, and its one order smaller time-step than the classical MD, all of which pose significant computational challenges in simulation capability to reach spatio-temporal scales of nanometers and nanoseconds. The very recent advances of graphics processing unit (GPU) provide not only highly favorable performance for GPU enabled MD programs compared with CPU implementations but also an opportunity to manage with the computing power and memory demanding nature imposed on computer hardware by ReaxFF MD. In this paper, we present the algorithms of GMD-Reax, the first GPU enabled ReaxFF MD program with significantly improved performance surpassing CPU implementations on desktop workstations. The performance of GMD-Reax has been benchmarked on a PC equipped with a NVIDIA C2050 GPU for coal pyrolysis simulation systems with atoms ranging from 1378 to 27,283. GMD-Reax achieved speedups as high as 12 times faster than Duin et al.'s FORTRAN codes in Lammps on 8 CPU cores and 6 times faster than the Lammps' C codes based on PuReMD in terms of the simulation time per time-step averaged over 100 steps. GMD-Reax could be used as a new and efficient computational tool for exploiting very complex molecular reactions via ReaxFF MD simulation on desktop workstations. Copyright © 2013 Elsevier Inc. All rights reserved.

Design of Simulink module for dynamic reactivity simulation of marine reactor automatic control rod

International Nuclear Information System (INIS)

Chen Zhiyun; Luo Lei; Chen Wenzhen; Gui Xuewen

2010-01-01

The power of marine reactor varies frequently and acutely, which induces the frequent and acute adjustment of the automatic control rod. According to the characteristics of marine reactor and the problem of improper control rod reactivity insertion in previous literatures, the Simulink module for dynamic reactivity simulation of automatic control rod was designed and adopted as a sub-module of Simulink program for the fast calculation of the physical and thermal parameters of marine reactor. A typical dynamic process of the marine reactor was used as the benchmark, which indicates that the designed Simulink module is capable of the dynamic simulation of automatic control rod position and reactivity, and is adequate to the fast calculation of physic and thermal parameters. The Simulink module is of significant meaning to the simulation of the dynamic process of marine reactor and the fast calculation of the operating parameters. (authors)

Synthesis of functional nanocrystallites through reactive thermal plasma processing

Directory of Open Access Journals (Sweden)

Takamasa Ishigaki and Ji-Guang Li

2007-01-01

Full Text Available A method of synthesizing functional nanostructured powders through reactive thermal plasma processing has been developed. The synthesis of nanosized titanium oxide powders was performed by the oxidation of solid and liquid precursors. Quench gases, either injected from the shoulder of the reactor or injected counter to the plasma plume from the bottom of the reactor, were used to vary the quench rate, and therefore the particle size, of the resultant powders. The experimental results are well supported by numerical analysis on the effects of the quench gas on the flow pattern and temperature field of the thermal plasma as well as on the trajectory and temperature history of the particles. The plasma-synthesized TiO2 nanoparticles showed phase preferences different from those synthesized by conventional wet-chemical processes. Nanosized particles of high crystallinity and nonequilibrium chemical composition were formed in one step via reactive thermal plasma processing.

Digital reactivity meter

International Nuclear Information System (INIS)

Akkus, B.; Anac, H.; Alsan, S.; Erk, S.

1991-01-01

Nowadays, various digital methods making use of microcomputers for neutron detector signals and determining the reactivity by numerical calculations are used in reactor control systems in place of classical reactivity meters. In this work, a calculation based on the ''The Time Dependent Transport Equation'' has been developed for determining the reactivity numerically. The reactivity values have been obtained utilizing a computer-based data acquisition and control system and compared with the analog reactivity meter values as well as the values calculated from the ''Inhour Equation''

Adjusting kinematics and kinetics in a feedback-controlled toe walking model

Directory of Open Access Journals (Sweden)

Olenšek Andrej

2012-08-01

Full Text Available Abstract Background In clinical gait assessment, the correct interpretation of gait kinematics and kinetics has a decisive impact on the success of the therapeutic programme. Due to the vast amount of information from which primary anomalies should be identified and separated from secondary compensatory changes, as well as the biomechanical complexity and redundancy of the human locomotion system, this task is considerably challenging and requires the attention of an experienced interdisciplinary team of experts. The ongoing research in the field of biomechanics suggests that mathematical modeling may facilitate this task. This paper explores the possibility of generating a family of toe walking gait patterns by systematically changing selected parameters of a feedback-controlled model. Methods From the selected clinical case of toe walking we identified typical toe walking characteristics and encoded them as a set of gait-oriented control objectives to be achieved in a feedback-controlled walking model. They were defined as fourth order polynomials and imposed via feedback control at the within-step control level. At the between-step control level, stance leg lengthening velocity at the end of the single support phase was adaptively adjusted after each step so as to facilitate gait velocity control. Each time the gait velocity settled at the desired value, selected intra-step gait characteristics were modified by adjusting the polynomials so as to mimic the effect of a typical therapeutical intervention - inhibitory casting. Results By systematically adjusting the set of control parameters we were able to generate a family of gait kinematic and kinetic patterns that exhibit similar principal toe walking characteristics, as they were recorded by means of an instrumented gait analysis system in the selected clinical case of toe walking. We further acknowledge that they to some extent follow similar improvement tendencies as those which one can

Measuring Physical Activity with Pedometers in Older Adults with Intellectual Disability : Reactivity and Number of Days

NARCIS (Netherlands)

Hilgenkamp, Thessa; Van Wijck, Ruud; Evenhuis, Heleen

The minimum number of days of pedometer monitoring needed to estimate valid average weekly step counts and reactivity was investigated for older adults with intellectual disability. Participants (N = 268) with borderline to severe intellectual disability ages 50 years and older were instructed to

A data acquisition protocol for a reactive wireless sensor network monitoring application.

Science.gov (United States)

Aderohunmu, Femi A; Brunelli, Davide; Deng, Jeremiah D; Purvis, Martin K

2015-04-30

Limiting energy consumption is one of the primary aims for most real-world deployments of wireless sensor networks. Unfortunately, attempts to optimize energy efficiency are often in conflict with the demand for network reactiveness to transmit urgent messages. In this article, we propose SWIFTNET: a reactive data acquisition scheme. It is built on the synergies arising from a combination of the data reduction methods and energy-efficient data compression schemes. Particularly, it combines compressed sensing, data prediction and adaptive sampling strategies. We show how this approach dramatically reduces the amount of unnecessary data transmission in the deployment for environmental monitoring and surveillance networks. SWIFTNET targets any monitoring applications that require high reactiveness with aggressive data collection and transmission. To test the performance of this method, we present a real-world testbed for a wildfire monitoring as a use-case. The results from our in-house deployment testbed of 15 nodes have proven to be favorable. On average, over 50% communication reduction when compared with a default adaptive prediction method is achieved without any loss in accuracy. In addition, SWIFTNET is able to guarantee reactiveness by adjusting the sampling interval from 5 min up to 15 s in our application domain.

Child Abuse, Resting Blood Pressure, and Blood Pressure Reactivity to Psychosocial Stress.

Science.gov (United States)

Gooding, Holly C; Milliren, Carly E; Austin, S Bryn; Sheridan, Margaret A; McLaughlin, Katie A

2016-01-01

Childhood trauma is associated with hypertension in adults. It is unknown whether childhood trauma predicts elevated blood pressure earlier in development. We investigated whether the trauma of child abuse was associated with blood pressure in adolescents. The sample included 145 adolescents aged 13-17 years, 40% with exposure to child abuse. The mean age of participants was 14.93 years (SD = 1.33); 58% were female. The majority self-identified as non-Hispanic White (43%), with the remainder identifying as non-Hispanic Black (17%), Hispanic (17%), or other/mixed race (23%). We used established age/sex/height-specific cutoffs to determine the prevalence of prehypertension and hypertension in the sample. We used two-sample t tests to examine associations of abuse with resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) and blood pressure reactivity to the Trier Social Stress Test and a frustration task. We used linear regression to adjust for potential confounders including sociodemographic variables, body mass index, smoking, and psychopathology. Mean resting SBP and DBP were 114.07 mmHg and 61.35 mmHg in those with a history of abuse and 111.39 mmHg and 56.89 mmHg in those without a history of abuse. This difference was significant for DBP only. Twelve percent of participants met criteria for prehypertension or hypertension based on resting blood pressure values; this did not differ between those with and without an abuse history. Child abuse was associated with lower DBP and SBP reactivity to laboratory stress tasks and reduced DBP reactivity to frustration. These associations were robust to adjustment for potential confounders. Child abuse is associated with higher resting DBP and blunted DBP and SBP reactivity to laboratory stress in adolescence. These findings suggest a potential pathway by which child abuse leads to hypertension. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All

Exploring the ‘ultimate’ step in the mediatization of political parties

DEFF Research Database (Denmark)

Ørsten, Mark; Willig, Ida; Pedersen, Leif Hemming

Previous studies exploring the fourth dimension of mediatization, that is to say the extent to which political parties adjust their perceptions and behaviour to news media logic, have focused on three steps of structural change that political parties may take as a response to the increasing......, parties may begin to especially focus on candidates who are skilled in communicating with the news media (Strömbäck & Van Alest, 2013).So far, research into the fourth dimension of mediatization in Denmark has focused mostly on the first two steps (Blach-Ørsten, 2016; Elmelund-Præstekær & Hopmann, 2016...

Step out - Step in Sequencing Games

NARCIS (Netherlands)

Musegaas, M.; Borm, P.E.M.; Quant, M.

2014-01-01

In this paper a new class of relaxed sequencing games is introduced: the class of Step out - Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order.

The impact of fuel temperature reactivity coefficient on loss of reactivity control accident

International Nuclear Information System (INIS)

Park, J. H.; Ryu, E. H.; Song, Y. M.; Jung, J. Y.

2012-01-01

Nuclear reactors experience small power fluctuations or anticipated operational transients during even normal power operation. During normal operation, the reactivity is mainly controlled by liquid zone controllers, adjuster rods, mechanical control absorbers, and moderator poison. Even when the reactor power is increased abruptly and largely from an accident and when reactor control systems cannot be actuated quickly due to a fast transient, the reactor should be controlled and stabilized by its inherent safety parameter, such as a negative PCR (Power Coefficient of Reactivity) feedback. A PWR (Pressurized Water Reactor), it is well designed for the reactor to have a negative PCR so that the reactor can be safely shut down or stabilized whenever an abrupt reactivity insertion into the reactor core occurs or the reactor power is abruptly increased. However, it is known that a CANDU reactor has a small amount of PCR, as either negative or positive, because of the different design basis and safety concepts from a PWR. CNSC's regulatory and safety regime has stated that; The PCR of CANDU reactors does not pose a significant risk. Consistent with Canadian nuclear safety requirements, nuclear power plants must have an appropriate combination of inherent and engineered safety features incorporated into the design of the reactor safety and control systems. A reactor design that has a PCR is quite acceptable provided that the reactor is stable against power fluctuations, and that the probability and consequences of any potential accidents that would be aggravated by a positive reactivity feedback are maintained within CNSCprescribed limits. Recently, it was issued licensing the refurbished Wolsong unit 1 in Korea to be operated continuously after its design lifetime in which the calculated PCR was shown to have a small positive value by applying the recent physics code systems, which are composed of WIMS IST, DRAGON IST, and RFSP IST. These code systems were transferred

Preparation for Compensatory Forward Stepping in Parkinson’s Disease

Science.gov (United States)

King, Laurie A.; St George, Rebecca J.; Carlson-Kuhta, Patricia; Nutt, John G.; Horak, Fay B.

2010-01-01

Objective To characterize preparation for compensatory stepping in people with Parkinson’s disease (PD) compared with healthy control subjects, and to determine whether levodopa medication improves preparation or the execution phases of the step. Design Observational study. Setting Outpatient neuroscience laboratory. Participants Nineteen participants with idiopathic PD tested both in the on and off levodopa states and 17 healthy subjects. Intervention Moveable platform with posterior translations of 24cm at 56cm/s. Main Outcome Measures Compensatory steps forward, in response to a backward surface translation (24cm amplitude at 56cm/s), were categorized according to the presence of an anticipatory postural adjustment (APA) before stepping: no APA, single APA, or multiple APAs. The following step parameters were calculated: step latency, step length, center of mass (CoM) average velocity, and CoM displacement at the step initiation. Results Lateral APAs were evident in 57% and 42% of trials for people with PD in the off and on medication states, respectively, compared with only 10% of trials for control subjects. Compared with subjects with PD who did not have APAs, those subjects with PD who did make an APA prior to stepping had significantly later (mean ± SEM, 356 ± 16ms vs 305 ± 8ms) and shorter (mean ± SEM, 251 ± 27mm vs 300 ± 16mm) steps, their CoM was significantly farther forward (185 ± 7mm vs 171 ± 5mm) at foot-off, and they took significantly more steps to regain equilibrium. Levodopa did not affect the preparation or execution phase of compensatory stepping. Poor axial scores and reports of freezing in the United Parkinson’s Disease Rating Scale were associated with use of 1 or more APAs before compensatory stepping. Conclusions Lateral postural preparation prior to compensatory stepping in subjects with PD was associated with inefficient balance recovery from external perturbations. PMID:20801249

Step out-step in sequencing games

NARCIS (Netherlands)

Musegaas, Marieke; Borm, Peter; Quant, Marieke

2015-01-01

In this paper a new class of relaxed sequencing games is introduced: the class of Step out–Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order. First,

Adjustment Criterion and Algorithm in Adjustment Model with Uncertain

Directory of Open Access Journals (Sweden)

SONG Yingchun

2015-02-01

Full Text Available Uncertainty often exists in the process of obtaining measurement data, which affects the reliability of parameter estimation. This paper establishes a new adjustment model in which uncertainty is incorporated into the function model as a parameter. A new adjustment criterion and its iterative algorithm are given based on uncertainty propagation law in the residual error, in which the maximum possible uncertainty is minimized. This paper also analyzes, with examples, the different adjustment criteria and features of optimal solutions about the least-squares adjustment, the uncertainty adjustment and total least-squares adjustment. Existing error theory is extended with new observational data processing method about uncertainty.

First-principles investigations of O2 dissociation on low-coordinated Pd ensembles over stepped Au surfaces

International Nuclear Information System (INIS)

Yuan, D.W.; Liu, Z.R.; Xu, Y.

2012-01-01

The adsorption and dissociation of O 2 on Pd monomer or trimer incorporated into Au(322) and Au(321) surfaces are systematically investigated by first-principles calculations and nudged-elastic-band simulations. We found that the contiguous low-coordinated Pd ensembles alloyed into step edges of Au surfaces are required for O 2 dissociation with an enhanced adsorption energy (∼−1.00 eV). The dissociative barrier of O 2 is mainly related to the size of Pd ensembles, and the activation energy is about 1.00 eV on Pd trimers. However, the Pd monomer is less active for the adsorption and dissociation of O 2 . Additionally, the O spillover from Pd to Au sites only occurs at elevated temperature, and the diffusion processes are highly endothermic. The calculated results indicate that the Pd-modified Au step edge with a contiguous Pd ensemble is the reactive center for supplying atomic oxygen on Pd-doped Au catalysts. -- Highlights: ► Our results reveal the mechanism of O 2 dissociation on Pd-decorated stepped Au surfaces. ► The adsorption energy of O 2 is related to both coordination numbers and geometrical arrangements of Pd atoms alloyed into Au surface. ► The Pd-modified Au step with a contiguous Pd ensemble is the reactive center for O 2 dissociation. ► Our results are important for understanding the catalytic properties of Pd-modified nanoporous gold, especially for those catalytic reactions related to O 2 activation.

Identifying elderly people at risk for cognitive decline by using the 2-step test.

Science.gov (United States)

Maruya, Kohei; Fujita, Hiroaki; Arai, Tomoyuki; Hosoi, Toshiki; Ogiwara, Kennichi; Moriyama, Shunnichiro; Ishibashi, Hideaki

2018-01-01

[Purpose] The purpose is to verify the effectiveness of the 2-step test in predicting cognitive decline in elderly individuals. [Subjects and Methods] One hundred eighty-two participants aged over 65 years underwent the 2-step test, cognitive function tests and higher level competence testing. Participants were classified as Robust, step test, variables were compared between groups. In addition, ordered logistic analysis was used to analyze cognitive functions as independent variables in the three groups, using the 2-step test results as the dependent variable, with age, gender, etc. as adjustment factors. [Results] In the crude data, the step test was related to the Stroop test (β: 0.06, 95% confidence interval: 0.01-0.12). [Conclusion] The finding is that the risk stage of the 2-step test is related to cognitive functions, even at an initial risk stage. The 2-step test may help with earlier detection and implementation of prevention measures for locomotive syndrome and mild cognitive impairment.

Reactivity and Synthetic Applications of 4,5-Dicyanopyridazine: An Overview

Directory of Open Access Journals (Sweden)

Donatella Giomi

2010-03-01

Full Text Available Despite the poor reputation of electron-deficient pyridazines in intermolecular Hetero Diels-Alder (HDA reactions, 4,5-dicyanopyridazine (DCP showed a surprising reactivity as a heterocyclic azadiene in inverse electron-demand HDA processes with different dienophiles. The use of alkenes, alkynes and enamines as 2p electron counterparts afforded dicyanocyclohexa-1,3-dienes and substituted phthalonitriles, respectively, while the use of suitable bis-dienophiles provides a general strategy for the one-pot synthesis of polycyclic carbo- and hetero-cage systemsthrough pericyclic three-step homodomino processes. HDA reactions with heterocyclic dienophiles allowed direct benzoannelation: in particular, pyrrole and indole derivatives were converted to dicyano-indoles and -carbazoles. In addition an unprecedented reactivity of DCP as a very reactive heterocyclic electrophile at the C-4 carbon was also evidenced: by changing the experimental conditions, cyanopyrrolyl- and cyanoindolyl-pyridazines were obtained through reactions of pyrrole and indole systems as carbon nucleophiles in formal SNAr2 processes where a CN group of DCP acts as leaving group. Thus, careful control of the reaction conditions allows exploitation of both pathways for the synthesis of different classes of heterocyclic derivatives.

Visible-light photocatalytic decolorization of reactive brilliant red X-3B on Cu{sub 2}O/crosslinked-chitosan nanocomposites prepared via one step process

Energy Technology Data Exchange (ETDEWEB)

Cao, Chunhua [College of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056 (China); Xiao, Ling, E-mail: xiaoling9119@yahoo.cn [College of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Liu, Li; Zhu, Huayue [College of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Chen, Chunhua; Gao, Lin [Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Chemical and Environmental Engineering, Jianghan University, Wuhan 430056 (China)

2013-04-15

Cu{sub 2}O/crosslinked-chitosan nanocomposites (Cu{sub 2}O/CS NCs) were in situ prepared via a simple one-step liquid phase precipitation–reduction process and characterized by XRD, FT-IR, SEM, TEM, BET, XPS and UV–vis/DRS. The characterization results showed that Cu{sub 2}O/CS NCs were almost similar spherical or ellipsoidal and the surface was rough and porous because Cu{sub 2}O particle was wrapped in chitosan. The chitosan layer was especially favorable for improving the adsorption ability of dye and molecular oxygen and restraining the recombination of electrons–holes pair. The visible-light photocatalytic decolorization behavior on Cu{sub 2}O/CS NCs was evaluated using reactive brilliant red X-3B (X-3B) as a model pollutant. The influences of various experimental factors on X-3B decolorization were investigated. It was found that the photocatalytic decolorization process on Cu{sub 2}O/CS NCs followed apparent pseudo-first-order kinetics model. The dye X-3B could be decolorized more efficiently in acidic media than in alkaline media. Cu{sub 2}O/CS NCs exhibited enhanced visible-light photocatalytic activity compared with other photocatalysts reported before under similar experimental conditions.

The Role of Chronic Psychosocial Stress in Explaining Racial Differences in Stress Reactivity and Pain Sensitivity.

Science.gov (United States)

Gordon, Jennifer L; Johnson, Jacqueline; Nau, Samantha; Mechlin, Beth; Girdler, Susan S

To examine the role of psychosocial factors in mediating the relationship between African American (AA) race and both increased pain sensitivity and blunted stress reactivity. Participants included 133 AA and non-Hispanic white (nHW) individuals (mean [SD] age, 37 [9]) matched for age, sex, and socioeconomic status. Participants underwent mental stress testing (Trier Social Stress Test) while cardiovascular, hemodynamic, and neuroendocrine reactivity were measured. Participants completed questionnaires assessing potential sources of psychosocial stress and were tested for pain responses to cold pain and the temporal summation of heat pulses. Mediation analyses were used to determine the extent to which exposure to psychosocial stress accounted for the observed racial differences in stress reactivity and pain. Chronic stress exposure and reactivity to mental stress was largely similar among AAs and nHWs; however, AAs exhibited heightened pain to both cold (p = .012) and heat (p = .004). Racial differences in the relationship between stress reactivity and pain were also observed: while greater stress reactivity was associated with decreased pain among nHWs, reactivity was either unrelated to or even positively associated with pain among AAs (e.g., r = -.21 among nHWs and r = .41 among AAs for stroke volume reactivity and cold pressor intensity). Adjusting for minor racial differences in chronic psychosocial stress did not change these findings. Accounting for psychosocial factors eliminated racial differences in stress reactivity but not racial differences in sensitivity to experimental pain tasks. Increased exposure to chronic stress may not explain AAs' increased pain sensitivity in laboratory settings.

Intrinsic photocatalytic assessment of reactively sputtered TiO₂ films.

Science.gov (United States)

Rafieian, Damon; Driessen, Rick T; Ogieglo, Wojciech; Lammertink, Rob G H

2015-04-29

Thin TiO2 films were prepared by DC magnetron reactive sputtering at different oxygen partial pressures. Depending on the oxygen partial pressure during sputtering, a transition from metallic Ti to TiO2 was identified by spectroscopic ellipsometry. The crystalline nature of the film developed during a subsequent annealing step, resulting in thin anatase TiO2 layers, displaying photocatalytic activity. The intrinsic photocatalytic activity of the catalysts was evaluated for the degradation of methylene blue (MB) using a microfluidic reactor. A numerical model was employed to extract the intrinsic reaction rate constants. High conversion rates (90% degradation within 20 s residence time) were observed within these microreactors because of the efficient mass transport and light distribution. To evaluate the intrinsic reaction kinetics, we argue that mass transport has to be accounted for. The obtained surface reaction rate constants demonstrate very high reactivity for the sputtered TiO2 films. Only for the thinnest film, 9 nm, slightly lower kinetics were observed.

Risk Selection, Risk Adjustment and Choice: Concepts and Lessons from the Americas

Science.gov (United States)

Ellis, Randall P.; Fernandez, Juan Gabriel

2013-01-01

Interest has grown worldwide in risk adjustment and risk sharing due to their potential to contain costs, improve fairness, and reduce selection problems in health care markets. Significant steps have been made in the empirical development of risk adjustment models, and in the theoretical foundations of risk adjustment and risk sharing. This literature has often modeled the effects of risk adjustment without highlighting the institutional setting, regulations, and diverse selection problems that risk adjustment is intended to fix. Perhaps because of this, the existing literature and their recommendations for optimal risk adjustment or optimal payment systems are sometimes confusing. In this paper, we present a unified way of thinking about the organizational structure of health care systems, which enables us to focus on two key dimensions of markets that have received less attention: what choices are available that may lead to selection problems, and what financial or regulatory tools other than risk adjustment are used to influence these choices. We specifically examine the health care systems, choices, and problems in four countries: the US, Canada, Chile, and Colombia, and examine the relationship between selection-related efficiency and fairness problems and the choices that are allowed in each country, and discuss recent regulatory reforms that affect choices and selection problems. In this sample, countries and insurance programs with more choices have more selection problems. PMID:24284351

Risk Selection, Risk Adjustment and Choice: Concepts and Lessons from the Americas

Directory of Open Access Journals (Sweden)

Randall P. Ellis

2013-10-01

Full Text Available Interest has grown worldwide in risk adjustment and risk sharing due to their potential to contain costs, improve fairness, and reduce selection problems in health care markets. Significant steps have been made in the empirical development of risk adjustment models, and in the theoretical foundations of risk adjustment and risk sharing. This literature has often modeled the effects of risk adjustment without highlighting the institutional setting, regulations, and diverse selection problems that risk adjustment is intended to fix. Perhaps because of this, the existing literature and their recommendations for optimal risk adjustment or optimal payment systems are sometimes confusing. In this paper, we present a unified way of thinking about the organizational structure of health care systems, which enables us to focus on two key dimensions of markets that have received less attention: what choices are available that may lead to selection problems, and what financial or regulatory tools other than risk adjustment are used to influence these choices. We specifically examine the health care systems, choices, and problems in four countries: the US, Canada, Chile, and Colombia, and examine the relationship between selection-related efficiency and fairness problems and the choices that are allowed in each country, and discuss recent regulatory reforms that affect choices and selection problems. In this sample, countries and insurance programs with more choices have more selection problems.

Persistent high job demands and reactivity to mental stress predict future ambulatory blood pressure.

Science.gov (United States)

Steptoe, A; Cropley, M

2000-05-01

To test the hypothesis that work stress (persistent high job demands over 1 year) in combination with high reactivity to mental stress predict ambulatory blood pressure. Assessment of cardiovascular responses to standardized behavioural tasks, job demands, and ambulatory blood pressure over a working day and evening after 12 months. We studied 81 school teachers (26 men, 55 women), 36 of whom experienced persistent high job demands over 1 year, while 45 reported lower job demands. Participants were divided on the basis of high and low job demands, and high and low systolic pressure reactions to an uncontrollable stress task. Blood pressure and concurrent physical activity were monitored using ambulatory apparatus from 0900 to 2230 h on a working day. Cardiovascular stress reactivity was associated with waist/hip ratio. Systolic and diastolic pressure during the working day were greater in high job demand participants who were stress reactive than in other groups, after adjustment for age, baseline blood pressure, body mass index and negative affectivity. The difference was not accounted for by variations in physical activity. Cardiovascular stress reactivity and sustained psychosocial stress may act in concert to increase cardiovascular risk in susceptible individuals.

Predicting algal growth inhibition toxicity: three-step strategy using structural and physicochemical properties.

Science.gov (United States)

Furuhama, A; Hasunuma, K; Hayashi, T I; Tatarazako, N

2016-05-01

We propose a three-step strategy that uses structural and physicochemical properties of chemicals to predict their 72 h algal growth inhibition toxicities against Pseudokirchneriella subcapitata. In Step 1, using a log D-based criterion and structural alerts, we produced an interspecies QSAR between algal and acute daphnid toxicities for initial screening of chemicals. In Step 2, we categorized chemicals according to the Verhaar scheme for aquatic toxicity, and we developed QSARs for toxicities of Class 1 (non-polar narcotic) and Class 2 (polar narcotic) chemicals by means of simple regression with a hydrophobicity descriptor and multiple regression with a hydrophobicity descriptor and a quantum chemical descriptor. Using the algal toxicities of the Class 1 chemicals, we proposed a baseline QSAR for calculating their excess toxicities. In Step 3, we used structural profiles to predict toxicity either quantitatively or qualitatively and to assign chemicals to the following categories: Pesticide, Reactive, Toxic, Toxic low and Uncategorized. Although this three-step strategy cannot be used to estimate the algal toxicities of all chemicals, it is useful for chemicals within its domain. The strategy is also applicable as a component of Integrated Approaches to Testing and Assessment.

Psychological and marital adjustment in couples following a traumatic brain injury (TBI): a critical review.

Science.gov (United States)

Blais, Marie Claude; Boisvert, Jean-Marie

2005-12-20

The first part of this paper examines current data describing the psychological and marital adjustment of couples following a traumatic brain injury (TBI). Although these findings reveal some discrepancies, they highlight that adjustment following a TBI represents a genuine challenge for those involved in the process. The second part moves toward the examination of factors associated with psychological and marital adjustment in both couple partners. Here again, there exists a large diversity in empirical data and theoretical models informing this emerging area of interest. Nevertheless, cognitive variables such as coping skills are commonly seen as critical variables to explain the adjustment level in people with TBI and their spouse/caregivers. Concurrently with the discussion of the methodological issues and pitfalls encountered in this area of research, the conclusion provides suggestions of further steps to undertake in this endeavour toward a better understanding of the adjustment process following TBI.

Prediction of Optimal Daily Step Count Achievement from Segmented School Physical Activity

Directory of Open Access Journals (Sweden)

Ryan D. Burns

2015-01-01

Full Text Available Optimizing physical activity in childhood is needed for prevention of disease and for healthy social and psychological development. There is limited research examining how segmented school physical activity patterns relate to a child achieving optimal physical activity levels. The purpose of this study was to examine the predictive relationship between step counts during specific school segments and achieving optimal school (6,000 steps/day and daily (12,000 steps/day step counts in children. Participants included 1,714 school-aged children (mean age = 9.7±1.0 years recruited across six elementary schools. Physical activity was monitored for one week using pedometers. Generalized linear mixed effects models were used to determine the adjusted odds ratios (ORs of achieving both school and daily step count standards for every 1,000 steps taken during each school segment. The school segment that related in strongest way to a student achieving 6,000 steps during school hours was afternoon recess (OR = 40.03; P<0.001 and for achieving 12,000 steps for the entire day was lunch recess (OR = 5.03; P<0.001. School segments including lunch and afternoon recess play an important role for optimizing daily physical activity in children.

A Reactive Transport Model for Marcellus Shale Weathering

Science.gov (United States)

Li, L.; Heidari, P.; Jin, L.; Williams, J.; Brantley, S.

2017-12-01

Shale formations account for 25% of the land surface globally. One of the most productive shale-gas formations is the Marcellus, a black shale that is rich in organic matter and pyrite. As a first step toward understanding how Marcellus shale interacts with water, we developed a reactive transport model to simulate shale weathering under ambient temperature and pressure conditions, constrained by soil chemistry and water data. The simulation was carried out for 10,000 years, assuming bedrock weathering and soil genesis began right after the last glacial maximum. Results indicate weathering was initiated by pyrite dissolution for the first 1,000 years, leading to low pH and enhanced dissolution of chlorite and precipitation of iron hydroxides. After pyrite depletion, chlorite dissolved slowly, primarily facilitated by the presence of CO2 and organic acids, forming vermiculite as a secondary mineral. A sensitivity analysis indicated that the most important controls on weathering include the presence of reactive gases (CO2 and O2), specific surface area, and flow velocity of infiltrating meteoric water. The soil chemistry and mineralogy data could not be reproduced without including the reactive gases. For example, pyrite remained in the soil even after 10,000 years if O2 was not continuously present in the soil column; likewise, chlorite remained abundant and porosity remained small with the presence of soil CO2. The field observations were only simulated successfully when the specific surface areas of the reactive minerals were 1-3 orders of magnitude smaller than surface area values measured for powdered minerals, reflecting the lack of accessibility of fluids to mineral surfaces and potential surface coating. An increase in the water infiltration rate enhanced weathering by removing dissolution products and maintaining far-from-equilibrium conditions. We conclude that availability of reactive surface area and transport of H2O and gases are the most important

Removal of chromate in a permeable reactive barrier using zero-valent iron

DEFF Research Database (Denmark)

Kjeldsen, Peter; Locht, T

2002-01-01

Chromate is a commonly found groundwater contaminant. Permeable reactive barriers containing zero-valent iron as iron filings are able to remove the chromate by a combined reduction/precipitation reaction. However, due to the passivation of the reduction capability of the iron surfaces by the pre......). Mixing in sand had no significant enhancing effect on the removal capacity, in contrast to a pH adjustment of the groundwater to pH 4, which significantly increased the removal capacity....

Making an Adjustable C-Clamp. Kit No. 603. Instructor's Manual [and] Student Learning Activity Manual. [Revised.] T & I--Metalwork.

Science.gov (United States)

White, Jim; Alexander, Larry

This student activity kit consists of a programmed, self-instructional learning guide and an accompanying instructor's manual for use in teaching trade and industrial education students how to make an adjustable C-clamp. The student guide contains step-by-step instructions in the following areas: basic layout principles; use of a hack saw, file,…

Convexity Adjustments

DEFF Research Database (Denmark)

M. Gaspar, Raquel; Murgoci, Agatha

2010-01-01

A convexity adjustment (or convexity correction) in fixed income markets arises when one uses prices of standard (plain vanilla) products plus an adjustment to price nonstandard products. We explain the basic and appealing idea behind the use of convexity adjustments and focus on the situations...

BN600 reactivity definition

International Nuclear Information System (INIS)

Zheltyshev, V.; Ivanov, A.

2000-01-01

Since 1980, the fast BN600 reactor with sodium coolant has been operated at Beloyarsk Nuclear Power Plant. The periodic monitoring of the reactivity modifications should be implemented in compliance with the standards and regulations applied in nuclear power engineering. The reactivity measurements are carried out in order to confirm the basic neutronic features of a BN600 reactor. The reactivity measurements are aimed to justify that nuclear safety is provided in course of the in-reactor installation of the experimental core components. Two reactivity meters are to be used on BN600 operation: 1. Digital on-line reactivity calculated under stationary reactor operation on power (approximation of the point-wise kinetics is applied). 2. Second reactivity meter used to define the reactor control rod operating components efficiency under reactor startup and take account of the changing efficiency of the sensor, however, this is more time-consumptive than the on-line reactivity meter. The application of two reactivity meters allows for the monitoring of the reactor reactivity under every operating mode. (authors)

ITP Adjuster 1.0: A New Utility Program to Adjust Charges in the Topology Files Generated by the PRODRG Server

Directory of Open Access Journals (Sweden)

Diogo de Jesus Medeiros

2013-01-01

Full Text Available The suitable computation of accurate atomic charges for the GROMACS topology *.itp files of small molecules, generated in the PRODRG server, has been a tricky task nowadays because it does not calculate atomic charges using an ab initio method. Usually additional steps of structure optimization and charges calculation, followed by a tedious manual replacement of atomic charges in the *.itp file, are needed. In order to assist this task, we report here the ITP Adjuster 1.0, a utility program developed to perform the replacement of the PRODRG charges in the *.itp files of small molecules by ab initio charges.

Automatic efficiency optimization of an axial compressor with adjustable inlet guide vanes

Science.gov (United States)

Li, Jichao; Lin, Feng; Nie, Chaoqun; Chen, Jingyi

2012-04-01

The inlet attack angle of rotor blade reasonably can be adjusted with the change of the stagger angle of inlet guide vane (IGV); so the efficiency of each condition will be affected. For the purpose to improve the efficiency, the DSP (Digital Signal Processor) controller is designed to adjust the stagger angle of IGV automatically in order to optimize the efficiency at any operating condition. The A/D signal collection includes inlet static pressure, outlet static pressure, outlet total pressure, rotor speed and torque signal, the efficiency can be calculated in the DSP, and the angle signal for the stepping motor which control the IGV will be sent out from the D/A. Experimental investigations are performed in a three-stage, low-speed axial compressor with variable inlet guide vanes. It is demonstrated that the DSP designed can well adjust the stagger angle of IGV online, the efficiency under different conditions can be optimized. This establishment of DSP online adjustment scheme may provide a practical solution for improving performance of multi-stage axial flow compressor when its operating condition is varied.

Free Modal Algebras Revisited: The Step-by-Step Method

NARCIS (Netherlands)

Bezhanishvili, N.; Ghilardi, Silvio; Jibladze, Mamuka

2012-01-01

We review the step-by-step method of constructing finitely generated free modal algebras. First we discuss the global step-by-step method, which works well for rank one modal logics. Next we refine the global step-by-step method to obtain the local step-by-step method, which is applicable beyond

SYSTEMATIZATION OF THE BASIC STEPS OF THE STEP-AEROBICS

Directory of Open Access Journals (Sweden)

Darinka Korovljev

2011-03-01

Full Text Available Following the development of the powerful sport industry, in front of us appeared a lot of new opportunities for creating of the new programmes of exercising with certain requisites. One of such programmes is certainly step-aerobics. Step-aerobics can be defined as a type of aerobics consisting of the basic aerobic steps (basic steps applied in exercising on stepper (step bench, with a possibility to regulate its height. Step-aerobics itself can be divided into several groups, depending on the following: type of music, working methods and adopted knowledge of the attendants. In this work, the systematization of the basic steps in step-aerobics was made on the basis of the following criteria: steps origin, number of leg motions in stepping and relating the body support at the end of the step. Systematization of the basic steps of the step-aerobics is quite significant for making a concrete review of the existing basic steps, thus making creation of the step-aerobics lesson easier

Amygdala reactivity and negative emotionality: divergent correlates of antisocial personality and psychopathy traits in a community sample.

Science.gov (United States)

Hyde, Luke W; Byrd, Amy L; Votruba-Drzal, Elizabeth; Hariri, Ahmad R; Manuck, Stephen B

2014-02-01

Previous studies have emphasized that antisocial personality disorder (APD) and psychopathy overlap highly but differ critically in several features, notably negative emotionality (NEM) and possibly amygdala reactivity to social signals of threat and distress. Here we examined whether dimensions of psychopathy and APD correlate differentially with NEM and amygdala reactivity to emotional faces. Testing these relationships among healthy individuals, dimensions of psychopathy and APD were generated by the profile matching technique of Lynam and Widiger (2001), using facet scales of the NEO Personality Inventory-Revised, and amygdala reactivity was measured using a well-established emotional faces task, in a community sample of 103 men and women. Higher psychopathy scores were associated with lower NEM and lower amygdala reactivity, whereas higher APD scores were related to greater NEM and greater amygdala reactivity, but only after overlapping variance in APD and psychopathy was adjusted for in the statistical model. Amygdala reactivity did not mediate the relationship of APD and psychopathy scores to NEM. Supplemental analyses also compared other measures of factors within psychopathy in predicting NEM and amygdala reactivity and found that Factor 2 psychopathy was positively related to NEM and amygdala reactivity across measures of psychopathy. The overall findings replicate seminal observations on NEM in psychopathy by Hicks and Patrick (2006) and extend this work to neuroimaging in a normative population. They also suggest that one critical way in which APD and psychopathy dimensions may differ in their etiology is through their opposing levels of NEM and amygdala reactivity to threat. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Toward a Global Bundle Adjustment of SPOT 5 - HRS Images

Science.gov (United States)

Massera, S.; Favé, P.; Gachet, R.; Orsoni, A.

2012-07-01

The HRS (High Resolution Stereoscopic) instrument carried on SPOT 5 enables quasi-simultaneous acquisition of stereoscopic images on wide segments - 120 km wide - with two forward and backward-looking telescopes observing the Earth with an angle of 20° ahead and behind the vertical. For 8 years IGN (Institut Géographique National) has been developing techniques to achieve spatiotriangulation of these images. During this time the capacities of bundle adjustment of SPOT 5 - HRS spatial images have largely improved. Today a global single block composed of about 20,000 images can be computed in reasonable calculation time. The progression was achieved step by step: first computed blocks were only composed of 40 images, then bigger blocks were computed. Finally only one global block is now computed. In the same time calculation tools have improved: for example the adjustment of 2,000 images of North Africa takes about 2 minutes whereas 8 hours were needed two years ago. To reach such a result a new independent software was developed to compute fast and efficient bundle adjustments. In the same time equipment - GCPs (Ground Control Points) and tie points - and techniques have also evolved over the last 10 years. Studies were made to get recommendations about the equipment in order to make an accurate single block. Tie points can now be quickly and automatically computed with SURF (Speeded Up Robust Features) techniques. Today the updated equipment is composed of about 500 GCPs and studies show that the ideal configuration is around 100 tie points by square degree. With such an equipment, the location of the global HRS block becomes a few meters accurate whereas non adjusted images are only 15 m accurate. This paper will describe the methods used in IGN Espace to compute a global single block composed of almost 20,000 HRS images, 500 GCPs and several million of tie points in reasonable calculation time. Many advantages can be found to use such a block. Because the

Executive functioning performance predicts subjective and physiological acute stress reactivity: preliminary results.

Science.gov (United States)

Hendrawan, Donny; Yamakawa, Kaori; Kimura, Motohiro; Murakami, Hiroki; Ohira, Hideki

2012-06-01

Individual differences in baseline executive functioning (EF) capacities have been shown to predict state anxiety during acute stressor exposure. However, no previous studies have clearly demonstrated the relationship between EF and physiological measures of stress. The present study investigated the efficacy of several well-known EF tests (letter fluency, Stroop test, and Wisconsin Card Sorting Test) in predicting both subjective and physiological stress reactivity during acute psychosocial stress exposure. Our results show that letter fluency served as the best predictor for both types of reactivity. Specifically, the higher the letter fluency score, the lower the acute stress reactivity after controlling for the baseline stress response, as indicated by lower levels of state anxiety, negative mood, salivary cortisol, and skin conductance. Moreover, the predictive power of the letter fluency test remained significant for state anxiety and cortisol indices even after further adjustments for covariates by adding the body mass index (BMI) as a covariate. Thus, good EF performance, as reflected by high letter fluency scores, may dampen acute stress responses, which suggests that EF processes are directly associated with aspects of stress regulation. Copyright © 2012 Elsevier B.V. All rights reserved.

One-step Maskless Fabrication and Optical Characterization of Silicon Surfaces with Antireflective Properties and a White Color Appearance

DEFF Research Database (Denmark)

Sun, Ling; Feidenhans'l, Nikolaj Agentoft; Telecka, Agnieszka

2016-01-01

We report a simple one-step maskless fabrication of inverted pyramids on silicon wafers by reactive ion etching. The fabricated surface structures exhibit excellent anti-reflective properties: The total reflectance of the nano inverted pyramids fabricated by our method can be as low as 12% withou...... milky white color....

Reactivity effects of fission product decay in PWRs

International Nuclear Information System (INIS)

Aragones, J.M.; Ahnert, C.

1988-01-01

The purpose of the work reported in this paper is to analyze the effects of fission product chains with radioactive decay on the reactivity in pressurized water reactor (PWR) cores, calculating their accumulation and absorption rates along fuel burnup at continuous operation and after shutdown periods extending from 1 day to a few months. The authors PWR version of the WIMS-D4 code is first used to obtain the individual number densities, absorption rates, and averaged cross sections for every nuclide of the fission product chains with significant decay rates, as a function of fuel burnup at continuous irradiation. Next, by an auxiliary ad hoc code, these data, have been processed together with the required one for fissile nuclides and boron, also taken from WIMS at each burnup step, to calculate the average or effective values relevant for the analysis and the decay and change in overall absorption after several shutdown times. (1) The reactivity effect of fission product decay changes significantly with the shutdown time. The maximum absorption increase by decay is reached in ∼ 10 days' shutdown. (2) The dependence with fuel type, enrichment, and burnup is slight, but the change with previous power density is nearly linear, which might be significant after coast-down in previous cycles. (3) For long shutdown periods, the overall reactivity effect of decay in the three fission product chains considered is much less than if only the samarium peak due to 149 Nd is considered

Method of controlling reactivity

International Nuclear Information System (INIS)

Tochihara, Hiroshi.

1982-01-01

Purpose: To improve the reactivity controlling characteristics by artificially controlling the leakage of neutron from a reactor and providing a controller for controlling the reactivity. Method: A reactor core is divided into several water gaps to increase the leakage of neutron, its reactivity is reduced, a gas-filled control rod or a fuel assembly is inserted into the gap as required, the entire core is coupled in a system to reduce the leakage of the neutron, and the reactivity is increased. The reactor shutdown is conducted by the conventional control rod, and to maintain critical state, boron density varying system is used together. Futher, a control rod drive is used with that similar to the conventional one, thereby enabling fast reactivity variation, and the positive reactivity can be obtained by the insertion, thereby improving the reactivity controlling characteristics. (Yoshihara, H.)

Hydrogen with intrinsic CO{sub 2} sequestration: the ENI 'One Step Hydrogen' process

Energy Technology Data Exchange (ETDEWEB)

Rossini, S.; Cornaro, U.; Mizia, F.; Malandrino, A.; Piccoli, V. [Enitecnologie SpA, S. Donata Milanese (Italy); Sanfilippo, D.; Miracca, I. [Snamprogetti SpA, S. Donato Milanese (Italy)

2003-07-01

The new process, under development in our companies, is aimed to hydrogen production with intrinsic carbon dioxide sequestration. This is made possible combining in a cycle the water oxidative potential with a reverse action by a reducing agent like hydrocarbons, the preferred being natural gas. In the first step a suitable oxide takes up the oxygen from water splitting producing hydrogen. The solid act as an oxygen storage medium. Such 'lattice' oxygen is in turn released through one or more elemental steps. The process fits very well with a circulating fluid bed reactor which allows the movement of the solid from one reactive environment to the other. (orig.)

Reactive Arthritis

Directory of Open Access Journals (Sweden)

Eren Erken

2013-06-01

Full Text Available Reactive arthritis is an acute, sterile, non-suppurative and inflammatory arthropaty which has occured as a result of an infectious processes, mostly after gastrointestinal and genitourinary tract infections. Reiter syndrome is a frequent type of reactive arthritis. Both reactive arthritis and Reiter syndrome belong to the group of seronegative spondyloarthropathies, associated with HLA-B27 positivity and characterized by ongoing inflammation after an infectious episode. The classical triad of Reiter syndrome is defined as arthritis, conjuctivitis and urethritis and is seen only in one third of patients with Reiter syndrome. Recently, seronegative asymmetric arthritis and typical extraarticular involvement are thought to be adequate for the diagnosis. However, there is no established criteria for the diagnosis of reactive arthritis and the number of randomized and controlled studies about the therapy is not enough. [Archives Medical Review Journal 2013; 22(3.000: 283-299

TRANC – a novel fast-response converter to measure total reactive atmospheric nitrogen

Directory of Open Access Journals (Sweden)

V. Wolff

2012-05-01

Full Text Available The input and loss of plant available nitrogen (reactive nitrogen: Nr from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter, which offers the opportunity to quantify the sum of all airborne reactive nitrogen compounds (∑Nr in high time resolution. The basic concept of the TRANC is the full conversion of all Nr to nitrogen monoxide (NO within two reaction steps. Initially, reduced Nr compounds are being oxidised, and oxidised Nr compounds are thermally converted to lower oxidation states. Particulate Nr is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher nitrogen oxides or those generated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3−, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in ∑Nr concentrations and also matches the sum of all individual Nr compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal

Objectively Measured Daily Steps and Subsequent Long Term All-Cause Mortality: The Tasped Prospective Cohort Study.

Directory of Open Access Journals (Sweden)

Terence Dwyer

Full Text Available Self-reported physical activity has been inversely associated with mortality but the effect of objectively measured step activity on mortality has never been evaluated. The objective is to determine the prospective association of daily step activity on mortality among free-living adults.Cohort study of free-living adults residing in Tasmania, Australia between 2000 and 2005 who participated in one of three cohort studies (n = 2 576 total participants. Daily step activity by pedometer at baseline at a mean of 58.8 years of age, and for a subset, repeated monitoring was available 3.7 (SD 1.3 years later (n = 1 679. All-cause mortality (n = 219 deaths was ascertained by record-linkage to the Australian National Death Index; 90% of participants were followed-up over ten years, until June 2011. Higher daily step count at baseline was linearly associated with lower all-cause mortality (adjusted hazard ratio AHR, 0.94; 95% CI, 0.90 to 0.98 per 1 000 steps; P = 0.004. Risk was altered little by removing deaths occurring in the first two years. Increasing baseline daily steps from sedentary to 10 000 steps a day was associated with a 46% (95% CI, 18% to 65%; P = 0.004 lower risk of mortality in the decade of follow-up. In addition, those who increased their daily steps over the monitoring period had a substantial reduction in mortality risk, after adjusting for baseline daily step count (AHR, 0.39; 95% CI, 0.22 to 0.72; P = 0.002, or other factors (AHR, 0.38; 95% CI, 0.21-0.70; P = 0.002.Higher daily step count was linearly associated with subsequent long term mortality among free living adults. These data are the first to quantify mortality reductions using an objective measure of physical activity in a free living population. They strongly underscore the importance of physical inactivity as a major public health problem.

Radiological safety aspects during handling of adjuster rod (cobalt-60) samples at Cirus

International Nuclear Information System (INIS)

Yadav, R.K.B.; Prasad, S.K.; Khuspe, R.R.; Babu, K.S.; Kamble, M.K.; Deshpande, S.B.; Srivastava, Alok; Ramesh, N.; Sharma, R.C.

2008-01-01

Cobalt -60 produced from the irradiation of the 59 Co capsules in adjuster rod of Cirus is used in many medical and industrial applications such as radiation therapy, sterilization of agricultural products, sterilization of medical equipment, industrial gamma exposure devices, nucleonic gauging sources etc. Two adjuster rods used for adjusting small reactivity loads (3.5 mk at 40 MW) in reactor contain thirty 59 Co slugs each. The 59 Co slugs are in the form of small capsules. These slugs were irradiated for nearly 3 years of full power operation. Since the amount of activity handled in the adjuster rod is very high (35 - 40 kCi), adequate radiological safety coverage is to be provided during the transfer of adjuster rod from the reactor pile to Tray Rod Facility (TRF) and during remote handling and loading of adjuster rod samples in shipping flask at TRF. Radiation fields observed are 0.4 - 3.0 Gy/h. In Cirus, falling of Adjuster rod from vertical flask at top of pile could result in declaration of evacuation emergency due to potential hazards associated with the high radiation field (∼26 Gy/h at 1m) of 60 Co slugs. Entire process of remote handling is viewed through lead glass and movement of samples is carried out with the help of a pair of master slave manipulator (MSM) arms. TRF with full samples give a radiation background of 0.2 - 20 mGy/h, requiring control of movement of personnel in the area. This paper explains in detail about the health physics aspects during handling of adjuster rod from reactor pile to TRF and back to pile, unloading and loading of radioisotope samples, operational radiation protection experience gained and collective dose consumed for the above transfer and loading job. The collective dose consumed in the handling of two adjuster rods is 8.7 per-mSv. (author)

Vitamin D and C-Reactive Protein: A Mendelian Randomization Study.

Directory of Open Access Journals (Sweden)

Marte C Liefaard

Full Text Available Vitamin D deficiency is widely prevalent and has been associated with many diseases. It has been suggested that vitamin D has effects on the immune system and inhibits inflammation. The aim of our study was to investigate whether vitamin D has an inhibitory effect on systemic inflammation by assessing the association between serum levels of vitamin D and C-reactive protein. We studied the association between serum 25-hydroxyvitamin D and C-reactive protein through linear regression in 9,649 participants of the Rotterdam Study, an observational, prospective population-based cohort study. We used genetic variants related to vitamin D and CRP to compute a genetic risk score and perform bi-directional Mendelian randomization analysis. In linear regression adjusted for age, sex, cohort and other confounders, natural log-transformed CRP decreased with 0.06 (95% CI: -0.08, -0.03 unit per standard deviation increase in 25-hydroxyvitamin D. Bi-directional Mendelian randomization analyses showed no association between the vitamin D genetic risk score and lnCRP (Beta per SD = -0.018; p = 0.082 or the CRP genetic risk score and 25-hydroxyvitamin D (Beta per SD = 0.001; p = 0.998. In conclusion, higher levels of Vitamin D are associated with lower levels of C-reactive protein. In this study we did not find evidence for this to be the result of a causal relationship.

Reactive Imprint Lithography: Combined Topographical Patterning and Chemical Surface Functionalization of Polystyrene-block-poly(tert-butyl acrylate) Films

NARCIS (Netherlands)

Duvigneau, Joost; Cornelissen, Stijn; Bardajı´Valls, Nuria; Schönherr, Holger; Vancso, Gyula J.

2009-01-01

Here, reactive imprint lithography (RIL) is introduced as a new, one-step lithographic tool for the fabrication of large-area topographically patterned, chemically activated polymer platforms. Films of polystyrene-block-poly(tert-butyl acrylate) (PS-b-PtBA) are imprinted with PDMS master stamps at

Reactivity and burnout of wood fuels

Energy Technology Data Exchange (ETDEWEB)

Dall' Ora, M.

2011-07-01

This thesis deals with the combustion of wood in pulverised fuel power plants. In this type of boiler, the slowest step in the wood conversion process is char combustion, which is one of the factors that not only determine the degree of fuel burnout, but also affect the heat release profile in the boiler and thereby the overall operation and efficiency of the plant. Chapter 1 consists of an introduction to thermal conversion of biomass fuels as well as a description of a Danish power plant where a measuring campaign was carried out as part of this project. Chapter 2 is a brief literature review of different aspects relevant to wood combustion, including wood structure and composition, wood pyrolysis, wood char properties and wood char oxidation. The full scale campaign, which is the subject of Chapter 3, included sampling of wood fuel before and after milling and sampling of gas and particles at the top of the combustion chamber. The collected samples and data are used to obtain an evaluation of the mills in operation at the power plant, the particle size distribution of the wood fuel, as well as the char conversion attained in the furnace. In Chapter 4 an experimental investigation on the relation between pyrolysis of wood in boiler-like conditions and wood char properties is presented. Chars from pine and beech wood were produced by fast pyrolysis in an entrained flow reactor and by slow pyrolysis in a thermogravimetric analyser. The influence of pyrolysis temperature, heating rate and particle size on char yield and morphology was investigated. The applied pyrolysis temperature varied in the range 673-1673 K for slow pyrolysis and 1073-1573 K for fast pyrolysis. The chars were oxidised in a thermogravimetric analyser and the mass loss data were used to determine char oxidation reactivity. Char yield from fast pyrolysis (104-105 K/s) was as low as 1-6% on a dry ash free basis, whereas it was about 15-17% for slow pyrolysis (10-20 K/min); char yield decreased as

RICE: a computer program for multicomponent chemically reactive flows at all speeds

International Nuclear Information System (INIS)

Rivard, W.C.; Farmer, O.A.; Butler, T.D.

1974-11-01

The fluid dynamics of chemically reactive mixtures are calculated at arbitrary flow speeds with the RICE program. The dynamics are governed by the two-dimensional, time-dependent Navier-Stokes equations together with the species transport equations and the mass-action rate equations for the chemical reactions. The mass and momentum equations for the mixture are solved implicitly by the ICE technique. The equations for total energy and species transport are solved explicitly while the chemical rate equations are solved implicitly with a time step that may be a submultiple of the hydrodynamic time step. Application is made to continuous wave HF chemical lasers to compute the supersonic mixing and chemical reactions that take place in the lasing cavity. (U.S.)

Immunological Reactivity Using Monoclonal and Polyclonal Antibodies of Autoimmune Thyroid Target Sites with Dietary Proteins

Directory of Open Access Journals (Sweden)

Datis Kharrazian

2017-01-01

Full Text Available Many hypothyroid and autoimmune thyroid patients experience reactions with specific foods. Additionally, food interactions may play a role in a subset of individuals who have difficulty finding a suitable thyroid hormone dosage. Our study was designed to investigate the potential role of dietary protein immune reactivity with thyroid hormones and thyroid axis target sites. We identified immune reactivity between dietary proteins and target sites on the thyroid axis that includes thyroid hormones, thyroid receptors, enzymes, and transport proteins. We also measured immune reactivity of either target specific monoclonal or polyclonal antibodies for thyroid-stimulating hormone (TSH receptor, 5′deiodinase, thyroid peroxidase, thyroglobulin, thyroxine-binding globulin, thyroxine, and triiodothyronine against 204 purified dietary proteins commonly consumed in cooked and raw forms. Dietary protein determinants included unmodified (raw and modified (cooked and roasted foods, herbs, spices, food gums, brewed beverages, and additives. There were no dietary protein immune reactions with TSH receptor, thyroid peroxidase, and thyroxine-binding globulin. However, specific antigen-antibody immune reactivity was identified with several purified food proteins with triiodothyronine, thyroxine, thyroglobulin, and 5′deiodinase. Laboratory analysis of immunological cross-reactivity between thyroid target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune thyroid disease.

Reactive Strength Index: A Poor Indicator of Reactive Strength?

Science.gov (United States)

Healy, Robin; Kenny, Ian; Harrison, Drew

2017-11-28

The primary aim was to assess the relationships between reactive strength measures and associated kinematic and kinetic performance variables achieved during drop jumps. A secondary aim was to highlight issues with the use of reactive strength measures as performance indicators. Twenty eight national and international level sprinters, consisting of fourteen men and women, participated in this cross-sectional analysis. Athletes performed drop jumps from a 0.3 m box onto a force platform with dependent variables contact time (CT), landing time (TLand), push-off time (TPush), flight time (FT), jump height (JH), reactive strength index (RSI, calculated as JH / CT), reactive strength ratio (RSR, calculated as FT / CT) and vertical leg spring stiffness (Kvert) recorded. Pearson's correlation test found very high to near perfect relationships between RSI and RSR (r = 0.91 to 0.97), with mixed relationships found between RSI, RSR and the key performance variables, (Men: r = -0.86 to -0.71 between RSI/RSR and CT, r = 0.80 to 0.92 between RSI/RSR and JH; Women: r = -0.85 to -0.56 between RSR and CT, r = 0.71 between RSI and JH). This study demonstrates that the method of assessing reactive strength (RSI versus RSR) may be influenced by the performance strategies adopted i.e. whether an athlete achieves their best reactive strength scores via low CTs, high JHs or a combination. Coaches are advised to limit the variability in performance strategies by implementing upper and / or lower CT thresholds to accurately compare performances between individuals.

Cardiac MRI in children and adolescents who have undergone surgical repair of right-sided congenital heart disease. Automated left ventricular volumes and function analysis and effects of different manual adjustments

Energy Technology Data Exchange (ETDEWEB)

Rompel, O.; Janka, R.; May, M.S.; Lell, M.M.; Uder, M.; Hammon, M. [University Hospital Erlangen (Germany). Dept. of Radiology; Gloeckler, M.; Dittrich, S. [University Hospital Erlangen (Germany). Dept. of Pediatric Cardiology; Cesnjevar, R. [University Hospital Erlangen (Germany). Dept. of Pediatric Cardiac Surgery

2015-12-15

To evaluate automated segmentation and the effects of different manual adjustments regarding left ventricular parameter quantification in cardiac magnetic resonance (MR) data on children and adolescents who have undergone surgical repair of right-sided congenital heart disease (CHD). Dedicated software (syngo.via, Siemens AG) was used to automatically segment and/or manually adjust the end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), myocardial mass (MM) and ejection fraction (EF) before/after manual apex/base adjustment (ADJ-step 1) and after manual apex/base/myocardial contour adjustment (ADJ-step 2; reference standard). MR data of 40 patients (13.1 ± 3.1y, 4-17y) with repaired CHD with decreased pulmonary blood flow (CHD-DPBF) were evaluated. Intra- and inter-rater reliability was determined for 10 randomly selected patients. The software correctly detected the left ventricle in 38/40 (95 %) patients. EDV after automated segmentation: 119.1 ± 44.0ml; after ADJ-step 1: 115.8 ± 39.5 ml; after ADJ-step 2: 116.2 ± 39.4 ml. The corresponding results for ESV were 52.0 ± 18.5/49.6 ± 16.9/49.7 ± 16.4 ml; for SV 67.1 ± 28.5/66.2 ± 25.4/66.5 ± 25.5 ml; for EF 55.5 ± 7.3/56.7 ± 6.6/56.7 ± 6.3%; for MM 83.7 ± 35.9/76.2 ± 28.3/74.6 ± 27.2 g. Significant differences were found for ESV/MM/EF comparing the automated segmentation results with these after ADJ-step 1 and ADJ-step 2. No significant differences were found when comparing all results of ADJ-step 1 and ADJ-step 2 or when comparing EDV/SV results. Intra- and inter-rater reliability was excellent. The mean time effort was 63.4 ± 6.9 s for the automated segmentation, 74.2 ± 8.9 s for ADJ-step 1 and 269.5 ± 39.4 s for ADJ-step 2. Automated left ventricular volumes and function analysis in children and adolescents with surgically treated CHD proved to be feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provided

Cardiac MRI in children and adolescents who have undergone surgical repair of right-sided congenital heart disease. Automated left ventricular volumes and function analysis and effects of different manual adjustments

International Nuclear Information System (INIS)

Rompel, O.; Janka, R.; May, M.S.; Lell, M.M.; Uder, M.; Hammon, M.; Gloeckler, M.; Dittrich, S.; Cesnjevar, R.

2015-01-01

To evaluate automated segmentation and the effects of different manual adjustments regarding left ventricular parameter quantification in cardiac magnetic resonance (MR) data on children and adolescents who have undergone surgical repair of right-sided congenital heart disease (CHD). Dedicated software (syngo.via, Siemens AG) was used to automatically segment and/or manually adjust the end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), myocardial mass (MM) and ejection fraction (EF) before/after manual apex/base adjustment (ADJ-step 1) and after manual apex/base/myocardial contour adjustment (ADJ-step 2; reference standard). MR data of 40 patients (13.1 ± 3.1y, 4-17y) with repaired CHD with decreased pulmonary blood flow (CHD-DPBF) were evaluated. Intra- and inter-rater reliability was determined for 10 randomly selected patients. The software correctly detected the left ventricle in 38/40 (95 %) patients. EDV after automated segmentation: 119.1 ± 44.0ml; after ADJ-step 1: 115.8 ± 39.5 ml; after ADJ-step 2: 116.2 ± 39.4 ml. The corresponding results for ESV were 52.0 ± 18.5/49.6 ± 16.9/49.7 ± 16.4 ml; for SV 67.1 ± 28.5/66.2 ± 25.4/66.5 ± 25.5 ml; for EF 55.5 ± 7.3/56.7 ± 6.6/56.7 ± 6.3%; for MM 83.7 ± 35.9/76.2 ± 28.3/74.6 ± 27.2 g. Significant differences were found for ESV/MM/EF comparing the automated segmentation results with these after ADJ-step 1 and ADJ-step 2. No significant differences were found when comparing all results of ADJ-step 1 and ADJ-step 2 or when comparing EDV/SV results. Intra- and inter-rater reliability was excellent. The mean time effort was 63.4 ± 6.9 s for the automated segmentation, 74.2 ± 8.9 s for ADJ-step 1 and 269.5 ± 39.4 s for ADJ-step 2. Automated left ventricular volumes and function analysis in children and adolescents with surgically treated CHD proved to be feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provided

Energy transfer in reactive and non-reactive H2 + OH collisions

International Nuclear Information System (INIS)

Rashed, O.; Brown, N.J.

1985-04-01

We have used the methods of quasi-classical dynamics to compute energy transfer properties of non-reactive and reactive H 2 + OH collisions. Energy transfer has been investigated as function of translational temperature, reagent rotational energy, and reagent vibrational energy. The energy transfer mechanism is complex with ten types of energy transfer possible, and evidence was found for all types. There is much more exchange between the translational degree of freedom and the H 2 vibrational degree of freedom than there is between translation and OH vibration. Translational energy is transferred to the rotational degrees of freedom of each molecule. There is a greater propensity for the transfer of translation to OH rotation than H 2 rotation. In reactive collisions, increases in reagent translational temperature predominantly appear as vibrational energy in the water molecule. Energy transfer in non-reactive and reactive collisions does not depend strongly on the initial angular momentum in either molecule. In non-reactive collisions, vibrational energy is transferred to translation, to the rotational degree of freedom of the same molecule, and to the rotational and vibrational degrees of freedom of the other molecule. In reactive collisions, the major effect of increasing the vibrational energy in reagent molecules is that, on the average, the vibrational energy of the reagents appears as product vibrational energy. 18 refs., 16 figs., 6 tabs

Reduced Reactivity of Amines against Nucleophilic Substitution via Reversible Reaction with Carbon Dioxide

Directory of Open Access Journals (Sweden)

Fiaz S. Mohammed

2015-12-01

Full Text Available The reversible reaction of carbon dioxide (CO2 with primary amines to form alkyl-ammonium carbamates is demonstrated in this work to reduce amine reactivity against nucleophilic substitution reactions with benzophenone and phenyl isocyanate. The reversible formation of carbamates has been recently exploited for a number of unique applications including the formation of reversible ionic liquids and surfactants. For these applications, reduced reactivity of the carbamate is imperative, particularly for applications in reactions and separations. In this work, carbamate formation resulted in a 67% reduction in yield for urea synthesis and 55% reduction for imine synthesis. Furthermore, the amine reactivity can be recovered upon reversal of the carbamate reaction, demonstrating reversibility. The strong nucleophilic properties of amines often require protection/de-protection schemes during bi-functional coupling reactions. This typically requires three separate reaction steps to achieve a single transformation, which is the motivation behind Green Chemistry Principle #8: Reduce Derivatives. Based upon the reduced reactivity, there is potential to employ the reversible carbamate reaction as an alternative method for amine protection in the presence of competing reactions. For the context of this work, CO2 is envisioned as a green protecting agent to suppress formation of n-phenyl benzophenoneimine and various n-phenyl–n-alky ureas.

Reactive sites influence in PMMA oligomers reactivity: a DFT study

Science.gov (United States)

Paz, C. V.; Vásquez, S. R.; Flores, N.; García, L.; Rico, J. L.

2018-01-01

In this work, we present a theoretical study of methyl methacrylate (MMA) living anionic polymerization. The study was addressed to understanding two important experimental observations made for Michael Szwarc in 1956. The unexpected effect of reactive sites concentration in the propagation rate, and the self-killer behavior of MMA (deactivating of living anionic polymerization). The theoretical calculations were performed by density functional theory (DFT) to obtain the frontier molecular orbitals values. These values were used to calculate and analyze the chemical interaction descriptors in DFT-Koopmans’ theorem. As a result, it was observed that the longest chain-length species (related with low concentration of reactive sites) exhibit the highest reactivity (behavior associated with the increase of the propagation rate). The improvement in this reactivity was attributed to the crosslinking produced in the polymethyl methacrylate chains. Meanwhile, the self-killer behavior was associated with the intermolecular forces present in the reactive sites. This behavior was associated to an obstruction in solvation, since the active sites remained active through all propagation species. The theoretical results were in good agreement with the Szwarc experiments.

Adaptive step-size algorithm for Fourier beam-propagation method with absorbing boundary layer of auto-determined width.

Science.gov (United States)

Learn, R; Feigenbaum, E

2016-06-01

Two algorithms that enhance the utility of the absorbing boundary layer are presented, mainly in the framework of the Fourier beam-propagation method. One is an automated boundary layer width selector that chooses a near-optimal boundary size based on the initial beam shape. The second algorithm adjusts the propagation step sizes based on the beam shape at the beginning of each step in order to reduce aliasing artifacts.

Low-cost ZnO:Al transparent contact by reactive rotatable magnetron sputtering for Cu(In,Ga)Se2 solar modules

International Nuclear Information System (INIS)

Menner, R.; Hariskos, D.; Linss, V.; Powalla, M.

2011-01-01

Sputtering ZnO as transparent front contact (TCO) is standard in today's industrial scale Cu(In,Ga)Se 2 (CIGS) module manufacturing. Although innovative concepts like rotatable magnetron sputtering from ceramic targets have been realised, costs are still high due to expensive ceramic targets. Significant cost reductions are expected by using reactive sputtering of metallic targets. Therefore, ZSW and industrial partners investigated the reactive sputtering of Al-doped zinc oxide (ZAO) as TCO on CIGS absorbers of high quality and industrial relevance. The reactive DC sputtering from rotatable magnetron targets is controlled in the transition mode by adjusting oxygen flow and discharge voltage. Optimisation leads to ZAO films with a TCO quality nearly comparable to standard films deposited by DC ceramic sputtering. Scanning electron microscopy, X-ray diffraction, and Hall analyses of the ZAO films are performed. Medium-size CIGS modules are coated with reactively sputtered ZAO, resulting in 12.8% module efficiency and surpassing the efficiency of the ceramic witness device. Cd-free buffered devices are also successfully coated with reactive TCO. Damp heat stability according to IEC61646 is met by all reactively sputtered devices.

Mode division multiplexing technology for single-fiber optical trapping axial-position adjustment.

Science.gov (United States)

Liu, Zhihai; Wang, Lei; Liang, Peibo; Zhang, Yu; Yang, Jun; Yuan, Libo

2013-07-15

We demonstrate trapped yeast cell axial-position adjustment without moving the optical fiber in a single-fiber optical trapping system. The dynamic axial-position adjustment is realized by controlling the power ratio of the fundamental mode beam (LP01) and the low-order mode beam (LP11) generated in a normal single-core fiber. In order to separate the trapping positions produced by the two mode beams, we fabricate a special fiber tapered tip with a selective two-step method. A yeast cell of 6 μm diameter is moved along the optical axis direction for a distance of ~3 μm. To the best of our knowledge, this is the first demonstration of the trapping position adjustment without moving the fiber for single-fiber optical tweezers. The excitation and utilization of multimode beams in a single fiber constitutes a new development for single-fiber optical trapping and makes possible more practical applications in biomedical research fields.

The effect of reactive emotions expressed in response to another's anger on inferences of social power.

Science.gov (United States)

Hareli, Shlomo; David, Shlomo

2017-06-01

Social perception of emotions is influenced by the context in which it occurs. One such context is a social interaction involving an exchange of emotions. The way parties to the interaction are perceived is shaped by the combination of emotions exchanged. This idea was examined by assessing the extent to which expressions of anger toward a target-which, in isolation, are perceived as signals of high social power-are influenced by the target's emotional reaction to it (i.e., reactive emotions). Three studies show that the angry person was perceived as having a higher level of social power when this anger was responded by fear or sadness than when it was responded by neutrality or anger. Study 1 indicated that reactive emotions have a stronger effect on perceived social power when emotions were incongruent with gender stereotypes. Study 2 indicated that these effects are a result of these emotions serving as reactive emotions rather than a benchmark against which the angry person's power is assessed. Study 3 showed that reactive emotions affect perceived social power by serving as signals of the level to which the high social power suggested by the first person's expression is confirmed by its target. Comparing effects of reactive emotions to anger with reactive emotions to sadness, showed that perceived social power of the expresser is determined by the nature of the expression, with some adjustment caused by the reactive emotions. This underscores the importance of social interaction as a context for the social perception of emotions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A reactive transport model for Marcellus shale weathering

Science.gov (United States)

Heidari, Peyman; Li, Li; Jin, Lixin; Williams, Jennifer Z.; Brantley, Susan L.

2017-11-01

Shale formations account for 25% of the land surface globally and contribute a large proportion of the natural gas used in the United States. One of the most productive shale-gas formations is the Marcellus, a black shale that is rich in organic matter and pyrite. As a first step toward understanding how Marcellus shale interacts with water in the surface or deep subsurface, we developed a reactive transport model to simulate shale weathering under ambient temperature and pressure conditions, constrained by soil and water chemistry data. The simulation was carried out for 10,000 years since deglaciation, assuming bedrock weathering and soil genesis began after the last glacial maximum. Results indicate weathering was initiated by pyrite dissolution for the first 1000 years, leading to low pH and enhanced dissolution of chlorite and precipitation of iron hydroxides. After pyrite depletion, chlorite dissolved slowly, primarily facilitated by the presence of CO2 and organic acids, forming vermiculite as a secondary mineral. A sensitivity analysis indicated that the most important controls on weathering include the presence of reactive gases (CO2 and O2), specific surface area, and flow velocity of infiltrating meteoric water. The soil chemistry and mineralogy data could not be reproduced without including the reactive gases. For example, pyrite remained in the soil even after 10,000 years if O2 was not continuously present in the soil column; likewise, chlorite remained abundant and porosity remained small if CO2 was not present in the soil gas. The field observations were only simulated successfully when the modeled specific surface areas of the reactive minerals were 1-3 orders of magnitude smaller than surface area values measured for powdered minerals. Small surface areas could be consistent with the lack of accessibility of some fluids to mineral surfaces due to surface coatings. In addition, some mineral surface is likely interacting only with equilibrated pore

Adjustment of positional geodetic networks by unconventional estimations

Directory of Open Access Journals (Sweden)

Silvia Gašincová

2010-06-01

Full Text Available The content of this paper is the adjustment of positional geodetic networks by robust estimations. The techniques (basedon the unconventional estimations of repeated least-square method which have turned out to be suitable and applicable in the practisehave been demonstrated on the example of the local geodetic network, which was founded to compose this thesis. In the thesisthe following techniques have been chosen to compare the Method of least-squares with those many published in foreign literature:M-estimation of Biweight,M-estimation of Welsch and Danish method. All presented methods are based on the repeated least-squaremethod principle with gradual changing of weight of individual measurements. In the first stage a standard least-square method wascarried out in the following steps – iterations we gradually change individual weights according to the relevant instructions/ regulation(so-called weight function. Iteration process will be stopped when no deviated measurements are found in the file of measured data.MatLab programme version 5.2 T was used to implement mathematical adjustment.

Increased platelet reactivity is associated with circulating platelet-monocyte complexes and macrophages in human atherosclerotic plaques.

Directory of Open Access Journals (Sweden)

Bert Rutten

Full Text Available Platelet reactivity, platelet binding to monocytes and monocyte infiltration play a detrimental role in atherosclerotic plaque progression. We investigated whether platelet reactivity was associated with levels of circulating platelet-monocyte complexes (PMCs and macrophages in human atherosclerotic carotid plaques.Platelet reactivity was determined by measuring platelet P-selectin expression after platelet stimulation with increasing concentrations of adenosine diphosphate (ADP, in two independent cohorts: the Circulating Cells cohort (n = 244 and the Athero-Express cohort (n = 91. Levels of PMCs were assessed by flow cytometry in blood samples of patients who were scheduled for percutaneous coronary intervention (Circulating Cells cohort. Monocyte infiltration was semi-quantitatively determined by histological examination of atherosclerotic carotid plaques collected during carotid endarterectomy (Athero-Express cohort.We found increased platelet reactivity in patients with high PMCs as compared to patients with low PMCs (median (interquartile range: 4153 (1585-11267 area under the curve (AUC vs. 9633 (3580-21565 AUC, P<0.001. Also, we observed increased platelet reactivity in patients with high macrophage levels in atherosclerotic plaques as compared to patients with low macrophage levels in atherosclerotic plaques (mean ± SD; 8969 ± 3485 AUC vs. 7020 ± 3442 AUC, P = 0.02. All associations remained significant after adjustment for age, sex and use of drugs against platelet activation.Platelet reactivity towards ADP is associated with levels of PMCs and macrophages in human atherosclerotic carotid plaques.

Reactivity on the Web

OpenAIRE

Bailey, James; Bry, François; Eckert, Michael; Patrânjan, Paula Lavinia

2005-01-01

Reactivity, the ability to detect simple and composite events and respond in a timely manner, is an essential requirement in many present-day information systems. With the emergence of new, dynamic Web applications, reactivity on the Web is receiving increasing attention. Reactive Web-based systems need to detect and react not only to simple events but also to complex, real-life situations. This paper introduces XChange, a language for programming reactive behaviour on the Web,...

Regression Trees Identify Relevant Interactions: Can This Improve the Predictive Performance of Risk Adjustment?

Science.gov (United States)

Buchner, Florian; Wasem, Jürgen; Schillo, Sonja

2017-01-01

Risk equalization formulas have been refined since their introduction about two decades ago. Because of the complexity and the abundance of possible interactions between the variables used, hardly any interactions are considered. A regression tree is used to systematically search for interactions, a methodologically new approach in risk equalization. Analyses are based on a data set of nearly 2.9 million individuals from a major German social health insurer. A two-step approach is applied: In the first step a regression tree is built on the basis of the learning data set. Terminal nodes characterized by more than one morbidity-group-split represent interaction effects of different morbidity groups. In the second step the 'traditional' weighted least squares regression equation is expanded by adding interaction terms for all interactions detected by the tree, and regression coefficients are recalculated. The resulting risk adjustment formula shows an improvement in the adjusted R 2 from 25.43% to 25.81% on the evaluation data set. Predictive ratios are calculated for subgroups affected by the interactions. The R 2 improvement detected is only marginal. According to the sample level performance measures used, not involving a considerable number of morbidity interactions forms no relevant loss in accuracy. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Single-Stage Step up/down Driver for Permanent-Magnet Synchronous Machines

Science.gov (United States)

Chen, T. R.; Juan, Y. L.; Huang, C. Y.; Kuo, C. T.

2017-11-01

The two-stage circuit composed of a step up/down dc converter and a three-phase voltage source inverter is usually adopted as the electric vehicle’s motor driver. The conventional topology is more complicated. Additional power loss resulted from twice power conversion would also cause lower efficiency. A single-stage step up/down Permanent-Magnet Synchronous Motor driver for Brushless DC (BLDC) Motor is proposed in this study. The number components and circuit complexity are reduced. The low frequency six-step square-wave control is used to reduce the switching losses. In the proposed topology, only one active switch is gated with a high frequency PWM signal for adjusting the rotation speed. The rotor position signals are fed back to calculate the motor speed for digital close-loop control in a MCU. A 600W prototype circuit is constructed to drive a BLDC motor with rated speed 3000 rpm, and can control the speed of six sections.

Intranasal Oxytocin Administration Dampens Amygdala Reactivity towards Emotional Faces in Male and Female PTSD Patients.

Science.gov (United States)

Koch, Saskia Bj; van Zuiden, Mirjam; Nawijn, Laura; Frijling, Jessie L; Veltman, Dick J; Olff, Miranda

2016-05-01

Post-traumatic stress disorder (PTSD) is a disabling psychiatric disorder. As a substantial part of PTSD patients responds poorly to currently available psychotherapies, pharmacological interventions boosting treatment response are needed. Because of its anxiolytic and pro-social properties, the neuropeptide oxytocin (OT) has been proposed as promising strategy for treatment augmentation in PTSD. As a first step to investigate the therapeutic potential of OT in PTSD, we conducted a double-blind, placebo-controlled, cross-over functional MRI study examining OT administration effects (40 IU) on amygdala reactivity toward emotional faces in unmedicated male and female police officers with (n=37, 21 males) and without (n=40, 20 males) PTSD. Trauma-exposed controls were matched to PTSD patients based on age, sex, years of service and educational level. Under placebo, the expected valence-dependent amygdala reactivity (ie, greater activity toward fearful-angry faces compared with happy-neutral faces) was absent in PTSD patients. OT administration dampened amygdala reactivity toward all emotional faces in male and female PTSD patients, but enhanced amygdala reactivity in healthy male and female trauma-exposed controls, independent of sex and stimulus valence. In PTSD patients, greater anxiety prior to scanning and amygdala reactivity during the placebo session were associated with greater reduction of amygdala reactivity after OT administration. Taken together, our results indicate presumably beneficial neurobiological effects of OT administration in male and female PTSD patients. Future studies should investigate OT administration in clinical settings to fully appreciate its therapeutic potential.

Tailoring the morphology and properties of poly(lactic acid)/poly(ethylene-co-vinyl acetate)/starch blends via reactive compatibilization

NARCIS (Netherlands)

Ma, P.; Hristova - Bogaerds, D.G.; Schmit, P.; Goossens, J.G.P.; Lemstra, P.J.

2012-01-01

Poly(lactic acid)/poly(ethylene-co-vinyl acetate)/starch (PLA/EVA/starch) ternary blends were prepared by multi-step melt processing (reactive extrusion) in the presence of maleic anhydride (MA), benzoyl peroxide and glycerol. The effects of MA and glycerol concentration on the morphology and

A one-step, real-time PCR assay for rapid detection of rhinovirus.

Science.gov (United States)

Do, Duc H; Laus, Stella; Leber, Amy; Marcon, Mario J; Jordan, Jeanne A; Martin, Judith M; Wadowsky, Robert M

2010-01-01

One-step, real-time PCR assays for rhinovirus have been developed for a limited number of PCR amplification platforms and chemistries, and some exhibit cross-reactivity with genetically similar enteroviruses. We developed a one-step, real-time PCR assay for rhinovirus by using a sequence detection system (Applied Biosystems; Foster City, CA). The primers were designed to amplify a 120-base target in the noncoding region of picornavirus RNA, and a TaqMan (Applied Biosystems) degenerate probe was designed for the specific detection of rhinovirus amplicons. The PCR assay had no cross-reactivity with a panel of 76 nontarget nucleic acids, which included RNAs from 43 enterovirus strains. Excellent lower limits of detection relative to viral culture were observed for the PCR assay by using 38 of 40 rhinovirus reference strains representing different serotypes, which could reproducibly detect rhinovirus serotype 2 in viral transport medium containing 10 to 10,000 TCID(50) (50% tissue culture infectious dose endpoint) units/ml of the virus. However, for rhinovirus serotypes 59 and 69, the PCR assay was less sensitive than culture. Testing of 48 clinical specimens from children with cold-like illnesses for rhinovirus by the PCR and culture assays yielded detection rates of 16.7% and 6.3%, respectively. For a batch of 10 specimens, the entire assay was completed in 4.5 hours. This real-time PCR assay enables detection of many rhinovirus serotypes with the Applied Biosystems reagent-instrument platform.

Digital reactivity meter

International Nuclear Information System (INIS)

Jiang Zongbing

1996-02-01

The importance and the usual methods of reactivity measurement in a nuclear reactor are presented. Emphasis is put upon the calculation principle, software and hardware components, main specifications, application, as well as the features of the digital reactivity meter. The test results of operation in various reactors shown that the meter possess the following features: high accuracy, short response time, low output noise, high resolution, wide measuring range, simple and flexible to operate, high stability and reliability. In addition, the reactivity meter can save the measuring data automatically and have a perfect capability of self-verifying. It not only meet the requirement of the reactivity measurement in nuclear power plant, but also can be applied to various types of reactors. (1 tab.)

Analysis of reactivity accidents of the RSG-GAS core with silicide fuel

International Nuclear Information System (INIS)

Tukiran

2002-01-01

The fuels of RSG-GAS reactor is changed from uranium oxide to uranium silicide. For time being, the fuel of RSG-GAS core are mixed up between oxide and silicide fuels with 250 gr of loading and 2.96 g U/cm 3 of density, respectively. While, silicide fuel with 300 gr of loading is still under research. The advantages of silicide fuels are can be used in high density, so that, it can be stayed longer in the core at higher burn-up, therefore, the length of cycle is longer. The silicide fuel in RSG-GAS core is used in step-wise by using mixed up core. Firstly, it is used silicide fuel with 250 gr of loading and then, silicide fuel with 300 gr of loading (3.55 g U/cm 3 of density). In every step-wise of fuel loading must be analysed its safety margin. In this occasion, it is analysed the reactivity accident of RSG-GAS core with 300 gr of silicide fuel loading. The calculation was done by using POKDYN code which available at P2TRR. The calculation was done by reactivity insertion at start up and power rangers. From all cases which were have been done, the results of analysis showed that there is no anomaly and safety margin break at RSG-GAS core with 300 gr silicide fuel loading

Use of the 'DRAGON' program for the calculation of reactivity devices

International Nuclear Information System (INIS)

Mollerach, Ricardo; Fink, Jose

2003-01-01

DRAGON is a computer program developed at the Ecole Polytechnique of the University of Montreal and adopted by AECL for the transport calculations associated to reactivity devices. This report presents aspects of the implementation in NASA of the DRAGON program. Some cases of interest were evaluated. Comparisons with results of known programs as WIMS D5, and with experiments were done. a) Embalse (CANDU 6) cell without burnup and leakage. Calculations of macroscopic cross sections with WIMS and DRAGON show very good agreement with smaller differences in the thermal constants. b) Embalse fresh cell with different leakage options. c) Embalse cell with leakage and burnup. A comparison of k-infinity and k-effective with WIMS and DRAGON as a function of burnup shows that the differences ((D-W)/D) for fresh fuel are -0.17% roughly constant up to about 2500 MWd/tU, and then decrease to -0.06 % for 8500 MWd/tU. Experiments made in 1977 in ZED-2 critical facility, reported in [3], were used as a benchmark for the cell and supercell DRAGON calculations. Calculated fluxes were compared with experimental values and the agreement is so good. d) ZED-2 cell calculation. The measured buckling was used as geometric buckling. This case can be considered an experimental verification. The calculated reactivity with DRAGON is about 2 mk, and can be considered satisfactory. WIMS k-effective value is about one mk higher. e) Supercell calculations for ZED-2 vertical and horizontal tube and rod adjuster using 2D and 3D models were done. Comparisons between measured and calculated fluxes in the vicinity of the adjuster rods. Incremental cross sections for these adjusters were calculated using different options. f) ZED-2 reactor calculations with PUMA reveal a good concordance with critical heights measured in experiments. The report describes also particular features of the code and recommendations regarding its use that may be useful for new users. (author)

Monadic Functional Reactive Programming

NARCIS (Netherlands)

A.J. van der Ploeg (Atze); C Shan

2013-01-01

htmlabstractFunctional Reactive Programming (FRP) is a way to program reactive systems in functional style, eliminating many of the problems that arise from imperative techniques. In this paper, we present an alternative FRP formulation that is based on the notion of a reactive computation: a

Core design of long life-cycle fast reactors operating without reactivity margin

International Nuclear Information System (INIS)

Aristova, E. N.; Baydin, D. F.; Gol'din, V. Y.; Pestryakova, G. A.; Stoynov, M. I.

2012-01-01

In this paper we consider a possibility of designing a fast reactor core that operates without reactivity margin for a long time. This study is based on the physical principle of fast reactor operating in a self-adjustable neutron-nuclear regime (SANNR-1) introduced by L.P. Feoktistov (1988-1993) and improved by V. Ya. Gol'din SANNR-2 (1995). The mathematical modeling of active zones of fast reactors in SANNR modes is held by authors since 1992. The numerical simulation is based on solving the neutron transport equation coupled with quasi-diffusion equations. The calculations have been performed using standard 26 energy groups. We use a hierarchy of spatial models of 1D, 1.5D, 2D, and 3D geometries. The spatial models of higher dimensionality are used for verification of results. The calculations showed that operation of the reactor in this mode increases its efficiency, safety and simplifies management. It is possible to achieve continuous work of the reactor in SANNR-2 during 7-10 years without fuel overloads by means of further optimization of the mode. Small reactivity margin is used only for the reactor start up. After first 10-15 days the reactor in SANNR-2 operates without reactivity margin. (authors)

A clinically relevant major cross-reactive allergen from mesquite tree pollen.

Science.gov (United States)

Dhyani, A; Singh, B P; Arora, N; Jain, V K; Sridhara, S

2008-10-01

Prosopis juliflora (mesquite) is one of the major sources of pollinosis in tropical and semi-arid countries of the world. The present study was undertaken to purify and characterize a major cross-reactive allergen from this tree species. Mesquite pollen extract was purified using reverse-phase chromatography. Allergen characterization was done by electrophoresis, enzyme-linked immunosorbent assay (ELISA) and Western blotting. Clinical relevance of the purified protein was analyzed by in vivo (skin tests) and in vitro experiments such as ELISA, histamine release, peripheral blood mononuclear cells (PBMC) proliferation and cytokine assays. Cross-reactivity of purified protein with allergenic tree species and lima bean (food) was assessed by inhibition assays. A 66-kDa protein was purified from mesquite pollen extract using octadecyl silica resin. Purified protein recognized 90% of mesquite-sensitized patients in skin test and ELISA. It induced significant histamine release in allergic patients' blood and interleukin-4 secretion in the PBMC culture supernatants. Inhibition assays suggested close allergenic relationship of this protein with Ailanthus excelsa, Cassia siamea, Salvadora persica pollen and Phaseolus lunatus (lima bean - an edible legume). A 66-kDa major cross-reactive allergen was isolated from mesquite pollen using single-step purification procedure. The protein seems relevant for clinical applications in allergic disorders.

Reactivity costs in MARIA reactor

International Nuclear Information System (INIS)

Marcinkowska, Zuzanna E.; Pytel, Krzysztof M.; Frydrysiak, Andrzej

2017-01-01

Highlights: • The methodology for calculating consumed fuel cost of excess reactivity is proposed. • Correlation between time integral of the core excess reactivity and released energy. • Reactivity price gives number of fuel elements required for given excess reactivity. - Abstract: For the reactor operation at high power level and carrying out experiments and irradiations the major cost of reactor operation is the expense of nuclear fuel. In this paper the methodology for calculating consumed fuel cost-relatedness of excess reactivity is proposed. Reactivity costs have been determined on the basis of operating data. A number of examples of calculating the reactivity costs for processes such as: strong absorbing material irradiation, molybdenium-99 production, beryllium matrix poisoning and increased moderator temperature illustrates proposed method.

Reactive Distillation for Esterification of Bio-based Organic Acids

Energy Technology Data Exchange (ETDEWEB)

Fields, Nathan; Miller, Dennis J.; Asthana, Navinchandra S.; Kolah, Aspi K.; Vu, Dung; Lira, Carl T.

2008-09-23

The following is the final report of the three year research program to convert organic acids to their ethyl esters using reactive distillation. This report details the complete technical activities of research completed at Michigan State University for the period of October 1, 2003 to September 30, 2006, covering both reactive distillation research and development and the underlying thermodynamic and kinetic data required for successful and rigorous design of reactive distillation esterification processes. Specifically, this project has led to the development of economical, technically viable processes for ethyl lactate, triethyl citrate and diethyl succinate production, and on a larger scale has added to the overall body of knowledge on applying fermentation based organic acids as platform chemicals in the emerging biorefinery. Organic acid esters constitute an attractive class of biorenewable chemicals that are made from corn or other renewable biomass carbohydrate feedstocks and replace analogous petroleum-based compounds, thus lessening U.S. dependence on foreign petroleum and enhancing overall biorefinery viability through production of value-added chemicals in parallel with biofuels production. Further, many of these ester products are candidates for fuel (particularly biodiesel) components, and thus will serve dual roles as both industrial chemicals and fuel enhancers in the emerging bioeconomy. The technical report from MSU is organized around the ethyl esters of four important biorenewables-based acids: lactic acid, citric acid, succinic acid, and propionic acid. Literature background on esterification and reactive distillation has been provided in Section One. Work on lactic acid is covered in Sections Two through Five, citric acid esterification in Sections Six and Seven, succinic acid in Section Eight, and propionic acid in Section Nine. Section Ten covers modeling of ester and organic acid vapor pressure properties using the SPEAD (Step Potential

Influence of the void fraction in the linear reactivity model

International Nuclear Information System (INIS)

Castillo, J.A.; Ramirez, J.R.; Alonso, G.

2003-01-01

The linear reactivity model allows the multicycle analysis in pressurized water reactors in a simple and quick way. In the case of the Boiling water reactors the void fraction it varies axially from 0% of voids in the inferior part of the fuel assemblies until approximately 70% of voids to the exit of the same ones. Due to this it is very important the determination of the average void fraction during different stages of the reactor operation to predict the burnt one appropriately of the same ones to inclination of the pattern of linear reactivity. In this work a pursuit is made of the profile of power for different steps of burnt of a typical operation cycle of a Boiling water reactor. Starting from these profiles it builds an algorithm that allows to determine the voids profile and this way to obtain the average value of the same one. The results are compared against those reported by the CM-PRESTO code that uses another method to carry out this calculation. Finally, the range in which is the average value of the void fraction during a typical cycle is determined and an estimate of the impact that it would have the use of this value in the prediction of the reactivity produced by the fuel assemblies is made. (Author)

Reactive perforating collagenosis

Directory of Open Access Journals (Sweden)

Yadav Mukesh

2009-01-01

Full Text Available Reactive perforating collagenosis is a rare cutaneous disorder of unknown etiology. We hereby describe a case of acquired reactive perforating collagenosis in a patient of diabetes and chronic renal failure.

C-reactive protein levels and treatment resistance in schizophrenia - A Danish population-based cohort study

DEFF Research Database (Denmark)

Horsdal, Henriette Thisted; Wimberley, Theresa; Benros, Michael Eriksen

2017-01-01

-time schizophrenia diagnosis and a baseline C-reactive protein measurement (a commonly available marker of systemic inflammation) from 2000 to 2012. We defined treatment resistance as the earliest observed instance of either clozapine initiation or hospital admission due to schizophrenia after having received......OBJECTIVE: Schizophrenia is associated with increased levels of inflammatory markers. However, it remains unclear whether inflammatory markers are associated with treatment-resistant schizophrenia. METHODS: We conducted a population-based follow-up study among individuals with a first...... (4.0 vs. 3.1 mg/L, p = .13) was observed among the 52 (13.3%) treatment-resistant individuals. Increased levels of C-reactive protein (above 3 mg/L) at baseline were not associated with treatment resistance (adjusted hazard ratio = 0.99, 95% confidence interval [0.56, 1.73]). CONCLUSIONS: C...

What makes ecological systems reactive?

Science.gov (United States)

Snyder, Robin E

2010-06-01

Although perturbations from a stable equilibrium must ultimately vanish, they can grow initially, and the maximum initial growth rate is called reactivity. Reactivity thus identifies systems that may undergo transient population surges or drops in response to perturbations; however, we lack biological and mathematical intuition about what makes a system reactive. This paper presents upper and lower bounds on reactivity for an arbitrary linearized model, explores their strictness, and discusses their biological implications. I find that less stable systems (i.e. systems with long transients) have a smaller possible range of reactivities for which no perturbations grow. Systems with more species have a higher capacity to be reactive, assuming species interactions do not weaken too rapidly as the number of species increases. Finally, I find that in discrete time, reactivity is determined largely by mean interaction strength and neither discrete nor continuous time reactivity are sensitive to food web topology. 2010 Elsevier Inc. All rights reserved.

Secure provision of reactive power ancillary services in competitive electricity markets

Science.gov (United States)

El-Samahy, Ismael

The research work presented in this thesis discusses various complex issues associated with reactive power management and pricing in the context of new operating paradigms in deregulated power systems, proposing appropriate policy solutions. An integrated two-level framework for reactive power management is set forth, which is both suitable for a competitive market and ensures a secure and reliable operation of the associated power system. The framework is generic in nature and can be adopted for any electricity market structure. The proposed hierarchical reactive power market structure comprises two stages: procurement of reactive power resources on a seasonal basis, and real-time reactive power dispatch. The main objective of the proposed framework is to provide appropriate reactive power support from service providers at least cost, while ensuring a secure operation of the power system. The proposed procurement procedure is based on a two-step optimization model. First, the marginal benefits of reactive power supply from each provider, with respect to system security, are obtained by solving a loadability-maximization problem subject to transmission security constraints imposed by voltage and thermal limits. Second, the selected set of generators is determined by solving an optimal power flow (OPF)-based auction. This auction maximizes a societal advantage function comprising generators' offers and their corresponding marginal benefits with respect to system security, and considering all transmission system constraints. The proposed procedure yields the selected set of generators and zonal price components, which would form the basis for seasonal contracts between the system operator and the selected reactive power service providers. The main objective of the proposed reactive power dispatch model is to minimize the total payment burden on the Independent System Operator (ISO), which is associated with reactive power dispatch. The real power generation is

Reduction of fluctuations in reactivity using symmetric matrix; Reduccion de fluctuaciones en la reactividad usando matriz simetrica

Energy Technology Data Exchange (ETDEWEB)

Suescun D, D.; Segovia Ch, F. A. [Universidad Surcolombiana, Facultad de Ciencias, Departamento de Fisica, Av. Pastrana Borrero - Carrera 1, Neiva, Huila (Colombia); Bonilla L, H. F., E-mail: daniel.suescun@usco.edu.co [Universidade Federal de Sao Carlos, Campus Sorocaba, Pos-Graduacao em Engenharia de Producao, Rodovia Joao Leme dos Santos SP-264, Km 110 Bairro do Itinga, CEP 18052-780 Sorocaba, Sao Paulo (Brazil)

2016-09-15

A new filtering method is presented in this work known as Savitzky-Golay (SG); allows reducing the fluctuations in the calculation of the reactivity. The filter softens and does not attenuate the nuclear power regardless of its shape, guaranteeing to decrease different degrees of noise with different steps of calculation time. This formulation employs a polynomial approximation of a certain degree to calculate the convolution coefficients. Its implementation is computational and avoids problems of bad conditioning, caused by the inversion of a linear system. The results show values in the maximum difference and in the averages absolute errors of the reactivity in comparison with that reported in the literature. (Author)

RETRANS, Reactivity Transients in LWR

International Nuclear Information System (INIS)

Kamelander, G.

1989-01-01

1 - Description of program or function: RETRANS is appropriate to calculate power excursions in light water reactors initiated by reactivity insertions due to withdrawal of control elements. As in the code TWIGL, the neutron physics model is based on the time-dependent two-group neutron diffusion equations. The equation of state of the coolant is approximated by a table built into the code. RETRANS solves the heat conduction equation and calculates the heat transfer coefficient for representative fuel rods at each time-step. 2 - Method of solution: The time-dependent neutron diffusion equations are modified by an exponential transformation and solved by means of a finite difference method. There is an option accelerating the inner iterations of the difference scheme by a coarse-mesh re-balancing method. The heat balance equations of the thermo- hydraulic model are discretized and converted into a tri-diagonal system of linear equations which is solved recursively. 3 - Restrictions on the complexity of the problem: r-z-geometry, one- phase-flow

NET SALARY ADJUSTMENT

CERN Multimedia

Finance Division

2001-01-01

On 15 June 2001 the Council approved the correction of the discrepancy identified in the net salary adjustment implemented on 1st January 2001 by retroactively increasing the scale of basic salaries to achieve the 2.8% average net salary adjustment approved in December 2000. We should like to inform you that the corresponding adjustment will be made to your July salary. Full details of the retroactive adjustments will consequently be shown on your pay slip.

Phase behavior and reactive transport of partial melt in heterogeneous mantle model

Science.gov (United States)

Jordan, J.; Hesse, M. A.

2013-12-01

front that followes a stationary melting front which creates low porosity intermediate states. Therefore, localization of the melt flow is not observed because the precipitation front is stable and the melting front is always stationary under these conditions. This analysis illustrates the counterintuitive behavior that can arise when the phase behavior is taken into account and is a first step to understanding reactive melt transport and the reactive constraints on channelization in partial melts. ¬¬

Within-step modulation of leg muscles activity by afferent feedback in human walking

DEFF Research Database (Denmark)

Klint, Richard af; Nielsen, Jens Bo; Cole, Jonathan D.

2008-01-01

To maintain smooth and efficient gait the motor system must adjust for changes in the ground on a step-to-step basis. In the present study we investigated the role of sensory feedback as 19 able-bodied human subjects walked over a platform that mimicked an uneven supporting surface. Triceps surae.......153+/-0.051; 3 degrees : 0.156+/-0.053) and significantly decreased when the platform was declined (-3 degrees : 0.133+/-0.048; -2 degrees : 0.132+/-0.049) compared with level walking (0.141+/-0.048) for the able-bodied subjects. A similar experiment was performed with a subject who lacked proprioception...

Adsorption studies of a water soluble dye, Reactive Red MF-3B, using sonication-surfactant-modified attapulgite clay

International Nuclear Information System (INIS)

Huang Jianhua; Liu Yuanfa; Jin Qingzhe; Wang Xingguo; Yang Jun

2007-01-01

The removal of water-soluble Reactive Red MF-3B from aqueous media by sonication-surfactant-modified attapulgite clay was studied in a batch system. The surfactant used was octodecyl trimethyl ammonium chloride (OTMAC). Adsorbent characterizations were investigated using X-ray diffraction, infrared spectroscopy, and surface area analysis. The effects of pH, contact time, initial solute concentration, adsorbent dose, and temperature on the adsorption of Reactive Red MF-3B onto modified clay were investigated. On the basis of kinetic studies, specific rate constants involved in the processes were calculated and second-order adsorption kinetics was observed in the case. Film diffusion was found to be the rate-limiting step. Reactive Red MF-3B adsorption was found to increase with increase temperature. The Reactive Red MF-3B equilibrium adsorption data were fitted to Freundlich and Langmuir isotherm models, the former being found to provide the better fit of the experimental data. Thermodynamic parameters were calculated. From the results it can be concluded that the surfactant-modified clay could be a good adsorbent for treating Reactive Red MF-3B-contaminated waters

Reactive Collision Avoidance Algorithm

Science.gov (United States)

Scharf, Daniel; Acikmese, Behcet; Ploen, Scott; Hadaegh, Fred

2010-01-01

The reactive collision avoidance (RCA) algorithm allows a spacecraft to find a fuel-optimal trajectory for avoiding an arbitrary number of colliding spacecraft in real time while accounting for acceleration limits. In addition to spacecraft, the technology can be used for vehicles that can accelerate in any direction, such as helicopters and submersibles. In contrast to existing, passive algorithms that simultaneously design trajectories for a cluster of vehicles working to achieve a common goal, RCA is implemented onboard spacecraft only when an imminent collision is detected, and then plans a collision avoidance maneuver for only that host vehicle, thus preventing a collision in an off-nominal situation for which passive algorithms cannot. An example scenario for such a situation might be when a spacecraft in the cluster is approaching another one, but enters safe mode and begins to drift. Functionally, the RCA detects colliding spacecraft, plans an evasion trajectory by solving the Evasion Trajectory Problem (ETP), and then recovers after the collision is avoided. A direct optimization approach was used to develop the algorithm so it can run in real time. In this innovation, a parameterized class of avoidance trajectories is specified, and then the optimal trajectory is found by searching over the parameters. The class of trajectories is selected as bang-off-bang as motivated by optimal control theory. That is, an avoiding spacecraft first applies full acceleration in a constant direction, then coasts, and finally applies full acceleration to stop. The parameter optimization problem can be solved offline and stored as a look-up table of values. Using a look-up table allows the algorithm to run in real time. Given a colliding spacecraft, the properties of the collision geometry serve as indices of the look-up table that gives the optimal trajectory. For multiple colliding spacecraft, the set of trajectories that avoid all spacecraft is rapidly searched on

PID controller auto-tuning based on process step response and damping optimum criterion.

Science.gov (United States)

Pavković, Danijel; Polak, Siniša; Zorc, Davor

2014-01-01

This paper presents a novel method of PID controller tuning suitable for higher-order aperiodic processes and aimed at step response-based auto-tuning applications. The PID controller tuning is based on the identification of so-called n-th order lag (PTn) process model and application of damping optimum criterion, thus facilitating straightforward algebraic rules for the adjustment of both the closed-loop response speed and damping. The PTn model identification is based on the process step response, wherein the PTn model parameters are evaluated in a novel manner from the process step response equivalent dead-time and lag time constant. The effectiveness of the proposed PTn model parameter estimation procedure and the related damping optimum-based PID controller auto-tuning have been verified by means of extensive computer simulations. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Long-Term Effectiveness of Stress Management at Work: Effects of the Changes in Perceived Stress Reactivity on Mental Health and Sleep Problems Seven Years Later.

Science.gov (United States)

Herr, Raphael M; Barrech, Amira; Riedel, Natalie; Gündel, Harald; Angerer, Peter; Li, Jian

2018-02-03

The reduction of stress reactivity resulting from stress management interventions prevents disorders and improves mental health, however, its long-term sustainability has been little examined. The objective of this study was, therefore, to determine the effectiveness of a stress management intervention, designed to improve stress reactivity, for mental health and sleep problems seven years later, using longitudinal data from 101 male industrial workers. Linear regressions estimated the adjusted effects of the changes in stress reactivity in general as well as in its six subdimensions (work overload, social conflict, social stress, failure at work, and anticipatory and prolonged reactivity) on depression, anxiety, and sleep problems seven years later. The improvement of the prolonged reactivity had positive effects on depression, anxiety, and sleep problems (unstandardized regression coefficients [ Bs ] ≥ 0.35, all p -values ≤ 0.01). Depression and sleep problems were further improved by a reduction of the reactivity to social conflicts ( Bs ≥ 0.29, p -values stress reactivity resulting from a work stress intervention was effective and generally long-lasting in preventing mental health and sleep problems. The reduction of the prolonged reactivity seems of particular importance and efficient in inhibiting negative stress manifestations.

A Preliminary Assessment of the Adjuster Rod Depletion Effect in the CANDU Reactor

International Nuclear Information System (INIS)

Kim, Yonghee; Roh, Gyuhong; Kim, Won Young; Kim, Hak Sung; Park, Joo Hwan

2008-01-01

Lifetime of the Wolsong-1 CANDU reactor, which will be shutdown in April, 2009. Major reactor components such as the pressure tube are to be replaced and it is expected that the CANDU reactor can be operated for additional 25-30 years. Meanwhile, all the reactivity devices including the adjuster rods (ADJ) are supposed to be continuously used without any change. In the CANDU reactor, 21 stainless steel (SS) ADJs are used to control the core power distribution and compensate for some reactivity loss during several abnormal cases. The ADJs are normally fully inserted and the SS absorber should undergo a slow depletion through neutron irradiation for a long time. In April, 2009, the accumulated FPY (Full Power Day) of Wolsong-1 is about 23 years. Depletion of ADJs should result in a smaller ADJ worth and a higher fuel burnup and the core power distribution should also be affected by the ADJ depletion. In this work, the effects of the ADJ depletion have been assessed in terms of ADJ worth, time-average core characteristics

Reactive power compensator

Science.gov (United States)

El-Sharkawi, Mohamed A.; Venkata, Subrahmanyam S.; Chen, Mingliang; Andexler, George; Huang, Tony

1992-01-01

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

Reactive power compensator

Energy Technology Data Exchange (ETDEWEB)

El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Woodinville, WA); Chen, Mingliang (Kirkland, WA); Andexler, George (Everett, WA); Huang, Tony (Seattle, WA)

1992-01-01

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

Digital reactivity meter

International Nuclear Information System (INIS)

Copie, M.; Valantic, B.

1978-01-01

Digital reactivity meters (DRM) are mostly used as measuring instruments, e.g. for calibration of control rods, and there are only a few cases of their incorporation into the control systems of the reactors. To move in this direction there is more development work needed. First of all, fast algorithms are needed for inverse kinetics equations to relieve the computer for more important tasks of reactor model solving in real time. The next problem, currently under investigation, is the incorporation of the reactor thermal-hydraulic model into the DRM so that it can be used in the power range. Such an extension of DHM allows presentation not only of the instantaneous reactivity of the system, but also the inserted reactivity can be estimated from the temperature reactivity feed-backs. One of the applications of this concept is the anomalous digital reactivity monitor (ADRN) as part of the reactor protection system. As a solution of the first problem, a fast algorithm for solving the inverse kinetics equations has been implemented in the off-line program RODCAL on CDC 1700 computer and tested for its accuracy by performing different control rod calibrations on the reactor TRIGA

Simulation of uranium oxides reduction kinetics by hydrogen. Reactivities of germination and growth

International Nuclear Information System (INIS)

Brun, C.

1997-01-01

The aim of this work is to simulate the reduction by hydrogen of the tri-uranium octo-oxide U 3 O 8 (obtained by uranium trioxide calcination) into uranium dioxide. The kinetics curves have been obtained by thermal gravimetric analysis, the hydrogen and steam pressures being defined. The geometrical modeling which has allowed to explain the trend of the kinetics curves and of the velocity curves is an anisotropic germination-growth modeling. The powder is supposed to be formed of spherical grains with the same radius. The germs of the new UO 2 phase appear at the surface of the U 3 O 8 grains with a specific germination frequency. The growth reactivity is anisotropic and is very large in the tangential direction to the grains surface. Then, the uranium dioxide growths inside the grain and the limiting step is the grain surface. The variations of the growth reactivity and of the germination specific frequency in terms of the gases partial pressures and of the temperature have been explained by two different mechanisms. The limiting step of the growth mechanism is the desorption of water in the uranium dioxide surface. Concerning the germination mechanism the limiting step is a water desorption too but in the tri-uranium octo-oxide surface. The same geometrical modeling and the same germination and growth mechanisms have been applied to the reduction of a tri-uranium octo-oxide obtained by calcination of hydrated uranium trioxide. The values of the germination specific frequency of this solid are nevertheless weaker than those of the solid obtained by direct calcination of the uranium trioxide. (O.M.)

Structure reactivity relationships during N2O hydrogenation over Au-Ag alloys: A study by field emission techniques

Science.gov (United States)

Jacobs, Luc; Barroo, Cédric; Gilis, Natalia; Lambeets, Sten V.; Genty, Eric; Visart de Bocarmé, Thierry

2018-03-01

To make available atomic oxygen at the surface of a catalyst is the key step for oxidation reactions on Au-based catalysts. In this context, Au-Ag alloys catalysts exhibit promising properties for selective oxidation reactions of alcohols: low temperature activity and high selectivity. The presence of O(ads) and its effects on the catalytic reactivity is studied via the N2O dissociative adsorption and subsequent hydrogenation. Field emission techniques are particularly suited to study this reaction: Field Ion Microscopy (FIM) and Field Emission Microscopy (FEM) enable to image the extremity of sharp metallic tips, the size and morphology of which are close to those of one single catalytic particle. The reaction dynamics is studied in the 300-320 K temperature range and at a pressure of 3.5 × 10-3 Pa. The main results are a strong structure/reactivity relationship during N2O + H2 reaction over Au-8.8 at.%Ag model catalysts. Comparison of high-resolution FIM images of the clean sample and FEM images during reaction shows a sensitivity of the reaction to the local structure of the facets, independently of the used partial pressures of both N2O and H2. This suggests a localised dissociative adsorption step for N2O and H2 with the formation of a reactive interface around the {210} facets.

Clinical reactivations of herpes simplex virus type 2 infection and human immunodeficiency virus disease progression markers.

Directory of Open Access Journals (Sweden)

Bulbulgul Aumakhan

Full Text Available BACKGROUND: The natural history of HSV-2 infection and role of HSV-2 reactivations in HIV disease progression are unclear. METHODS: Clinical symptoms of active HSV-2 infection were used to classify 1,938 HIV/HSV-2 co-infected participants of the Women's Interagency HIV Study (WIHS into groups of varying degree of HSV-2 clinical activity. Differences in plasma HIV RNA and CD4+ T cell counts between groups were explored longitudinally across three study visits and cross-sectionally at the last study visit. RESULTS: A dose dependent association between markers of HIV disease progression and degree of HSV-2 clinical activity was observed. In multivariate analyses after adjusting for baseline CD4+ T cell levels, active HSV-2 infection with frequent symptomatic reactivations was associated with 21% to 32% increase in the probability of detectable plasma HIV RNA (trend p = 0.004, an average of 0.27 to 0.29 log10 copies/ml higher plasma HIV RNA on a continuous scale (trend p<0.001 and 51 to 101 reduced CD4+ T cells/mm(3 over time compared to asymptomatic HSV-2 infection (trend p<0.001. CONCLUSIONS: HIV induced CD4+ T cell loss was associated with frequent symptomatic HSV-2 reactivations. However, effect of HSV-2 reactivations on HIV disease progression markers in this population was modest and appears to be dependent on the frequency and severity of reactivations. Further studies will be necessary to determine whether HSV-2 reactivations contribute to acceleration of HIV disease progression.

Two steps simultaneous analysis of reactivity of L-norvaline in the T-for-H exchange reaction. Application of Taft equation to influence of Polar effect and steric effect

International Nuclear Information System (INIS)

Kataoka, Noriaki; Imaizumi, Hiroshi; Saito, Hiroshi; Sato, Takayuki; Kano, Naoki

2010-01-01

In order to quantitatively evaluate the influence of tritium ( 3 H or T) on ecosystem and the reactivity of materials having H atoms, the hydrogen isotope exchange reaction (T-for-H exchange reaction) between L-norvaline and HTO vapor was observed at 50-70degC in the gas-solid system. Applying the A''-McKay plot method to data obtained in the reaction, the rate constants of the functional groups in the material were obtained. Comparing these rate constants, following seven matters have been found in the T-for-H exchange reaction. (1) The reactivity of the functional groups in L-norvaline increases with increasing temperature. (2) As to L-norvaline, 1) the temperature dependence of each functional group increases with the following order: COOH group > NH 2 one. 2) the reactivity of COOH group is 2.2 times greater than that of NH 2 one. (3) As to the influence of the substituent, the reactivity of COOH group is larger than that of the NH 2 one. (4) It seems that the reactivity of the amino acid follows Taft equation. (5) Applying Taft equation, the ratio of influence of polar effect to steric one is 10:0 in NH 2 group, and is 3:7 in COOH one. (6) Using the A - McKay plot method, the reactivity of each functional group in an amino acid is able to be nondestructively, quantitatively and simultaneously analyzed without using masking reagent. (7) The method used in this work may be useful to quickly determine the reactivity of the functional groups in the materials. (author)

Two-step estimation in ratio-of-mediator-probability weighted causal mediation analysis.

Science.gov (United States)

Bein, Edward; Deutsch, Jonah; Hong, Guanglei; Porter, Kristin E; Qin, Xu; Yang, Cheng

2018-04-15

This study investigates appropriate estimation of estimator variability in the context of causal mediation analysis that employs propensity score-based weighting. Such an analysis decomposes the total effect of a treatment on the outcome into an indirect effect transmitted through a focal mediator and a direct effect bypassing the mediator. Ratio-of-mediator-probability weighting estimates these causal effects by adjusting for the confounding impact of a large number of pretreatment covariates through propensity score-based weighting. In step 1, a propensity score model is estimated. In step 2, the causal effects of interest are estimated using weights derived from the prior step's regression coefficient estimates. Statistical inferences obtained from this 2-step estimation procedure are potentially problematic if the estimated standard errors of the causal effect estimates do not reflect the sampling uncertainty in the estimation of the weights. This study extends to ratio-of-mediator-probability weighting analysis a solution to the 2-step estimation problem by stacking the score functions from both steps. We derive the asymptotic variance-covariance matrix for the indirect effect and direct effect 2-step estimators, provide simulation results, and illustrate with an application study. Our simulation results indicate that the sampling uncertainty in the estimated weights should not be ignored. The standard error estimation using the stacking procedure offers a viable alternative to bootstrap standard error estimation. We discuss broad implications of this approach for causal analysis involving propensity score-based weighting. Copyright © 2018 John Wiley & Sons, Ltd.

Body configuration at first stepping-foot contact predicts backward balance recovery capacity in people with chronic stroke.

Science.gov (United States)

de Kam, Digna; Roelofs, Jolanda M B; Geurts, Alexander C H; Weerdesteyn, Vivian

2018-01-01

To determine the predictive value of leg and trunk inclination angles at stepping-foot contact for the capacity to recover from a backward balance perturbation with a single step in people after stroke. Twenty-four chronic stroke survivors and 21 healthy controls were included in a cross-sectional study. We studied reactive stepping responses by subjecting participants to multidirectional stance perturbations at different intensities on a translating platform. In this paper we focus on backward perturbations. Participants were instructed to recover from the perturbations with maximally one step. A trial was classified as 'success' if balance was restored according to this instruction. We recorded full-body kinematics and computed: 1) body configuration parameters at first stepping-foot contact (leg and trunk inclination angles) and 2) spatiotemporal step parameters (step onset, step length, step duration and step velocity). We identified predictors of balance recovery capacity using a stepwise logistic regression. Perturbation intensity was also included as a predictor. The model with spatiotemporal parameters (perturbation intensity, step length and step duration) could correctly classify 85% of the trials as success or fail (Nagelkerke R2 = 0.61). In the body configuration model (Nagelkerke R2 = 0.71), perturbation intensity and leg and trunk angles correctly classified the outcome of 86% of the recovery attempts. The goodness of fit was significantly higher for the body configuration model compared to the model with spatiotemporal variables (pmodel. Body configuration at stepping-foot contact is a valid and clinically feasible indicator of backward fall risk in stroke survivors, given its potential to be derived from a single sagittal screenshot.

Reactive dispersive contaminant transport in coastal aquifers: Numerical simulation of a reactive Henry problem

KAUST Repository

Nick, H.M.

2013-02-01

The reactive mixing between seawater and terrestrial water in coastal aquifers influences the water quality of submarine groundwater discharge. While these waters come into contact at the seawater groundwater interface by density driven flow, their chemical components dilute and react through dispersion. A larger interface and wider mixing zone may provide favorable conditions for the natural attenuation of contaminant plumes. It has been claimed that the extent of this mixing is controlled by both, porous media properties and flow conditions. In this study, the interplay between dispersion and reactive processes in coastal aquifers is investigated by means of numerical experiments. Particularly, the impact of dispersion coefficients, the velocity field induced by density driven flow and chemical component reactivities on reactive transport in such aquifers is studied. To do this, a hybrid finite-element finite-volume method and a reactive simulator are coupled, and model accuracy and applicability are assessed. A simple redox reaction is considered to describe the degradation of a contaminant which requires mixing of the contaminated groundwater and the seawater containing the terminal electron acceptor. The resulting degradation is observed for different scenarios considering different magnitudes of dispersion and chemical reactivity. Three reactive transport regimes are found: reaction controlled, reaction-dispersion controlled and dispersion controlled. Computational results suggest that the chemical components\\' reactivity as well as dispersion coefficients play a significant role on controlling reactive mixing zones and extent of contaminant removal in coastal aquifers. Further, our results confirm that the dilution index is a better alternative to the second central spatial moment of a plume to describe the mixing of reactive solutes in coastal aquifers. © 2012 Elsevier B.V.

2-Step scalar deadzone quantization for bitplane image coding.

Science.gov (United States)

Auli-Llinas, Francesc

2013-12-01

Modern lossy image coding systems generate a quality progressive codestream that, truncated at increasing rates, produces an image with decreasing distortion. Quality progressivity is commonly provided by an embedded quantizer that employs uniform scalar deadzone quantization (USDQ) together with a bitplane coding strategy. This paper introduces a 2-step scalar deadzone quantization (2SDQ) scheme that achieves same coding performance as that of USDQ while reducing the coding passes and the emitted symbols of the bitplane coding engine. This serves to reduce the computational costs of the codec and/or to code high dynamic range images. The main insights behind 2SDQ are the use of two quantization step sizes that approximate wavelet coefficients with more or less precision depending on their density, and a rate-distortion optimization technique that adjusts the distortion decreases produced when coding 2SDQ indexes. The integration of 2SDQ in current codecs is straightforward. The applicability and efficiency of 2SDQ are demonstrated within the framework of JPEG2000.

Reactive ion assisted deposition of aluminum oxynitride thin films

International Nuclear Information System (INIS)

Hwangbo, C.K.; Lingg, L.J.; Lehan, J.P.; Macleod, H.A.; Suits, F.

1989-01-01

Optical properties, stoichiometry, chemical bonding states, and crystal structure of aluminum oxynitride (AlO/sub x/N/sub y/) thin films prepared by reactive ion assisted deposition were investigated. The results show that by controlling the amount of reactive gases the refractive index of aluminum oxynitride films at 550 nm is able to be varied from 1.65 to 1.83 with a very small extinction coefficient. Variations of optical constants and chemical bonding states of aluminum oxynitride films are related to the stoichiometry. From an x-ray photoelectron spectroscopy analysis it is observed that our aluminum oxynitride film is not simply a mixture of aluminum oxide and aluminum nitride but a continuously variable compound. The aluminum oxynitride films are amorphous from an x-ray diffraction analysis. A rugate filter using a step index profile of aluminum oxynitride films was fabricated by nitrogen ion beam bombardment of a growing Al film with backfill oxygen pressure as the sole variation. This filter shows a high resistivity to atmospheric moisture adsorption, suggesting that the packing density of aluminum oxynitride films is close to unity and the energetic ion bombardment densifies the film as well as forming the compound

Integrated Design and Control of Reactive and Non-Reactive Distillation Processes

DEFF Research Database (Denmark)

Mansouri, Seyed Soheil; Sales-Cruz, Mauricio; Huusom, Jakob Kjøbsted

, an alternative approach is to tackle process design and controllability issues simultaneously, in the early stages of process design. This simultaneous synthesis approach provides optimal/near optimal operation and more efficient control of conventional (non-reactive binary distillation columns) (Hamid et al...... of methodologies have been proposed and applied on various problems to address the interactions between process design and control, and they range from optimization-based approaches to model-based methods (Sharifzadeh, 2013). In this work, integrated design and control of non-reactive distillation, ternary...... reactive distillation processes. The element concept (Pérez Cisneros et al., 1997) is used to translate a ternary system of compounds (A + B ↔ C) to a binary system of element (WA and WB). In the case of multicomponent reactive distillation processes the equivalent element concept is used to translate...

Programming Reactive Extensions and LINQ

CERN Document Server

Liberty, Jesse

2011-01-01

Pro Reactive Extensions and LINQ is a deep dive into the next important technology for .NET developers: Reactive Extensions. This in-depth tutorial goes beyond what is available anywhere else to teach how to write WPF, Silverlight, and Windows Phone applications using the Reactive Extensions (Rx) to handle events and asynchronous method calls. Reactive programming allows you to turn those aspects of your code that are currently imperative into something much more event-driven and flexible. For this reason, it's sometimes referred to as LINQ for Events. Reactive programming hinges on the concep

Influence of the dopant during the one step mechano-chemical synthesis of sodium alanate

International Nuclear Information System (INIS)

Rongeat, C; Geipel, C; Llamas-Jansa, I; Schultz, L; Gutfleisch, O

2009-01-01

High-pressure reactive milling under hydrogen atmosphere is used for the one-step synthesis of doped sodium alanate. In-situ monitoring of the pressure and the temperature inside the vial gives a direct feedback about the reactions occurring during the milling. This information is used to study the influence of the dopant during synthesis, e.g. the amount of dopant added. The study of the pressure variations during milling is a reliable tool for screening the efficiency of different dopants.

Urea impedimetric biosensor based on reactive RF magnetron sputtered zinc oxide nanoporous transducer

International Nuclear Information System (INIS)

Mozaffari, Sayed Ahmad; Rahmanian, Reza; Abedi, Mohammad; Amoli, Hossein Salar

2014-01-01

Graphical abstract: - Highlights: • Application and optimization of reactive RF magnetron sputtering for homogeneous nanoporous ZnO thin film formation. • Exploiting nanoporous ZnO thin film as a good porous framework with large surface area/volume for having stable immobilized enzyme with minimum loss of activity. • Application of impedimetric assessment for urea biosensing due to its rapidity, sensitivity, and repeatability. - Abstract: Uniform sputtered nanoporous zinc oxide (Nano-ZnO) thin film on the conductive fluorinated-tin oxide (FTO) layer was applied to immobilize urease enzyme (Urs) for urea detection. Highly uniform nanoporous ZnO thin film were obtained by reactive radio frequency (RF) magnetron sputtering system at the optimized instrumental deposition conditions. Characterization of the surface morphology and roughness of ZnO thin film by field emission-scanning electron microscopy (FE-SEM) exhibits cavities of nanoporous film as an effective biosensing area for enzyme immobilization. Step by step monitoring of FTO/Nano-ZnO/Urs biosensor fabrication were performed using electrochemical methods such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. Fabricated FTO/Nano-ZnO/Urs biosensor was used for urea determination using EIS experiments. The impedimetric results show high sensitivity for urea detection within 0.83–23.24 mM and limit of detection as 0.40 mM

Reducing Schoolchildren With Reactive Aggression Through Child, Parent, and Conjoint Parent-Child Group Interventions: A Longitudinal Outcome Effectiveness Study.

Science.gov (United States)

Fung, Annis Lai Chu

2017-10-10

This study was the first to evaluate the effectiveness of three different group interventions to reduce children's reactive aggression based on the social information processing (SIP) model. In the first stage of screening, 3,734 children of Grades 4-6 completed the Reactive-Proactive Aggression Questionnaire (RPQ) to assess their reactive and proactive aggression. Respondents with a total score of z ≥ 1 on the RPQ were shortlisted for the second stage of screening by qualitative interview. Interviews with 475 children were conducted to select those who showed reactive aggression featuring a hostile attributional bias. Finally, 126 children (97 males and 29 females) aged 8 to 14 (M = 9.71, SD = 1.23) were selected and randomly assigned to one of the three groups: a child group, a parent group, and a parent-child group. A significant Time × Intervention effect was found for general and reactive aggression. The parent-child group and child group showed a significant drop in general aggression and reactive aggression from posttest to 6-month follow-up, after controlling for baseline scores, sex, and age. However, the parent group showed no treatment effect: reactive aggression scores were significantly higher than those in the child group at 6-month follow-up. This study has provided strong evidence that children with reactive aggression need direct and specific treatment to reconstruct the steps of the SIP involving the selection and interpretation of cues. The intervention could help to prevent severe violent crimes at the later stage of a reactive aggressor. © 2017 Family Process Institute.

A Data-Driven Stochastic Reactive Power Optimization Considering Uncertainties in Active Distribution Networks and Decomposition Method

DEFF Research Database (Denmark)

Ding, Tao; Yang, Qingrun; Yang, Yongheng

2018-01-01

To address the uncertain output of distributed generators (DGs) for reactive power optimization in active distribution networks, the stochastic programming model is widely used. The model is employed to find an optimal control strategy with minimum expected network loss while satisfying all......, in this paper, a data-driven modeling approach is introduced to assume that the probability distribution from the historical data is uncertain within a confidence set. Furthermore, a data-driven stochastic programming model is formulated as a two-stage problem, where the first-stage variables find the optimal...... control for discrete reactive power compensation equipment under the worst probability distribution of the second stage recourse. The second-stage variables are adjusted to uncertain probability distribution. In particular, this two-stage problem has a special structure so that the second-stage problem...

Modulation of EMG-EMG Coherence in a Choice Stepping Task

Directory of Open Access Journals (Sweden)

Ippei Nojima

2018-02-01

Full Text Available The voluntary step execution task is a popular measure for identifying fall risks among elderly individuals in the community setting because most falls have been reported to occur during movement. However, the neurophysiological functions during this movement are not entirely understood. Here, we used electromyography (EMG to explore the relationship between EMG-EMG coherence, which reflects common oscillatory drive to motoneurons, and motor performance associated with stepping tasks: simple reaction time (SRT and choice reaction time (CRT tasks. Ten healthy elderly adults participated in the study. Participants took a single step forward in response to a visual imperative stimulus. EMG-EMG coherence was analyzed for 1000 ms before the presentation of the stimulus (stationary standing position from proximal and distal tibialis anterior (TA and soleus (SOL muscles. The main result showed that all paired EMG-EMG coherences in the alpha and beta frequency bands were greater in the SRT than the CRT task. This finding suggests that the common oscillatory drive to the motoneurons during the SRT task occurred prior to taking a step, whereas the lower value of corticospinal activity during the CRT task prior to taking a step may indicate an involvement of inhibitory activity, which is consistent with observations from our previous study (Watanabe et al., 2016. Furthermore, the beta band coherence in intramuscular TA tended to positively correlate with the number of performance errors that are associated with fall risks in the CRT task, suggesting that a reduction in the inhibitory activity may result in a decrease of stepping performance. These findings could advance the understanding of the neurophysiological features of postural adjustments in elderly individuals.

Step dynamics and terrace-width distribution on flame-annealed gold films: The effect of step-step interaction

International Nuclear Information System (INIS)

Shimoni, Nira; Ayal, Shai; Millo, Oded

2000-01-01

Dynamics of atomic steps and the terrace-width distribution within step bunches on flame-annealed gold films are studied using scanning tunneling microscopy. The distribution is narrower than commonly observed for vicinal planes and has a Gaussian shape, indicating a short-range repulsive interaction between the steps, with an apparently large interaction constant. The dynamics of the atomic steps, on the other hand, appear to be influenced, in addition to these short-range interactions, also by a longer-range attraction of steps towards step bunches. Both types of interactions promote self-ordering of terrace structures on the surface. When current is driven through the films a step-fingering instability sets in, reminiscent of the Bales-Zangwill instability

Lifespan changes in global and selective stopping and performance adjustments

Directory of Open Access Journals (Sweden)

Maria Christina Van De Laar

2011-12-01

Full Text Available This study examined stopping and performance adjustments in four age groups (M ages: 8, 12, 21, and 76 years. All participants performed on three tasks, a standard two-choice task and the same task in which stop-signal trials were inserted requiring either the suppression of the response activated by the choice stimulus (global stop task or the suppression of the response when one stop signal was presented but not when the other stop signal occurred (selective stop task. The results showed that global stopping was faster than selective stopping in all age groups. Global stopping matured more rapidly than selective stopping. The developmental gain in stopping was considerably more pronounced compared to the loss observed during senescence. All age groups slowed the response on trials without a stop signal in the stop task compared to trials in the choice task, the elderly in particular. In addition, all age groups slowed on trials following stop-signal trials, except the elderly who did not slow following successful inhibits. By contrast, the slowing following failed inhibits was disproportionally larger in the elderly compared to young adults. Finally, sequential effects did not alter the pattern of performance adjustments. The results were interpreted in terms of developmental change in the balance between proactive and reactive control.

Lifespan Changes in Global and Selective Stopping and Performance Adjustments

Science.gov (United States)

van de Laar, Maria C.; van den Wildenberg, Wery P. M.; van Boxtel, Geert J. M.; van der Molen, Maurits W.

2011-01-01

This study examined stopping and performance adjustments in four age groups (M ages: 8, 12, 21, and 76 years). All participants performed on three tasks, a standard two-choice task and the same task in which stop-signal trials were inserted requiring either the suppression of the response activated by the choice stimulus (global stop task) or the suppression of the response when one stop-signal was presented but not when the other stop-signal occurred (selective stop task). The results showed that global stopping was faster than selective stopping in all age groups. Global stopping matured more rapidly than selective stopping. The developmental gain in stopping was considerably more pronounced compared to the loss observed during senescence. All age groups slowed the response on trials without a stop-signal in the stop task compared to trials in the choice task, the elderly in particular. In addition, all age groups slowed on trials following stop-signal trials, except the elderly who did not slow following successful inhibits. By contrast, the slowing following failed inhibits was disproportionally larger in the elderly compared to young adults. Finally, sequential effects did not alter the pattern of performance adjustments. The results were interpreted in terms of developmental change in the balance between proactive and reactive control. PMID:22180746

Traffic safety and step-by-step driving licence for young people

DEFF Research Database (Denmark)

Tønning, Charlotte; Agerholm, Niels

2017-01-01

presents a review of safety effects from step-by-step driving licence schemes. Most of the investigated schemes consist of a step-by-step driving licence with Step 1) various tests and education, Step 2) a period where driving is only allowed together with an experienced driver and Step 3) driving without...... companion is allowed but with various restrictions and, in some cases, additional driving education and tests. In general, a step-by-step driving licence improves traffic safety even though the young people are permitted to drive a car earlier on. The effects from driving with an experienced driver vary......Young novice car drivers are much more accident-prone than other drivers - up to 10 times that of their parents' generation. A central solution to improve the traffic safety for this group is implementation of a step-by-step driving licence. A number of countries have introduced a step...

Transient voltage control of a DFIG-based wind power plant for suppressing overvoltage using a reactive current reduction loop

Directory of Open Access Journals (Sweden)

Geon Park

2016-01-01

Full Text Available This paper proposes a transient voltage control scheme of a doubly fed induction generator (DFIG-based wind power plant (WPP using a reactive current reduction loop to suppress the overvoltage at a point of interconnection (POI and DFIG terminal after a fault clearance. The change of terminal voltage of a DFIG is monitored at every predefined time period to detect the fault clearance. If the voltage change exceeds a set value, then the reactive current reduction loop reduces the reactive current reference in the DFIG controller using the step function. The reactive current injection of DFIGs in a WPP is rapidly reduced, and a WPP can rapidly suppress the overvoltage at a fault clearance because the reactive current reference is reduced. Using an electromagnetic transients program–released version (EMTP–RV simulator, the performance of the proposed scheme was validated for a model system comprising 20 units of a 5-MW DFIG considering various scenarios, such as fault and wind conditions. Test results show that the proposed scheme enables a WPP to suppress the overvoltage at the POI and DFIG terminal within a short time under grid fault conditions.

Process stabilization by peak current regulation in reactive high-power impulse magnetron sputtering of hafnium nitride

International Nuclear Information System (INIS)

Shimizu, T; Villamayor, M; Helmersson, U; Lundin, D

2016-01-01

A simple and cost effective approach to stabilize the sputtering process in the transition zone during reactive high-power impulse magnetron sputtering (HiPIMS) is proposed. The method is based on real-time monitoring and control of the discharge current waveforms. To stabilize the process conditions at a given set point, a feedback control system was implemented that automatically regulates the pulse frequency, and thereby the average sputtering power, to maintain a constant maximum discharge current. In the present study, the variation of the pulse current waveforms over a wide range of reactive gas flows and pulse frequencies during a reactive HiPIMS process of Hf-N in an Ar–N 2 atmosphere illustrates that the discharge current waveform is a an excellent indicator of the process conditions. Activating the reactive HiPIMS peak current regulation, stable process conditions were maintained when varying the N 2 flow from 2.1 to 3.5 sccm by an automatic adjustment of the pulse frequency from 600 Hz to 1150 Hz and consequently an increase of the average power from 110 to 270 W. Hf–N films deposited using peak current regulation exhibited a stable stoichiometry, a nearly constant power-normalized deposition rate, and a polycrystalline cubic phase Hf-N with (1 1 1)-preferred orientation over the entire reactive gas flow range investigated. The physical reasons for the change in the current pulse waveform for different process conditions are discussed in some detail. (paper)

Achieving 10,000 steps: a comparison of public transport users and drivers in a university setting.

Science.gov (United States)

Villanueva, Karen; Giles-Corti, Billie; McCormack, Gavin

2008-09-01

To compare pedometer steps of university students who used public transport and private motor vehicles to travel to and or from The University of Western Australia (UWA). 103 undergraduate students in 2006 recruited by e-mail and snowballing wore a pedometer for five consecutive university days, and completed a travel and physical activity diary. Compared with private motor vehicle users, public transport users performed more daily steps (11443 vs. 10242 steps/day, p=0.04) After adjusting for gender, age group and average daily minutes of self-reported leisure-time physical activity, the odds of achieving 10,000 steps/day was higher in public transport users compared with private motor vehicle users (OR 3.55; 95% CI 1.34-9.38, p=0.01). Walking associated with public transport use appeared to contribute to university students achieving higher levels of daily steps. Encouraging public transport use could help increase and maintain community physical activity levels.

A simple reactivity-meter system

International Nuclear Information System (INIS)

Ferreira, P.S.B.

1992-01-01

This paper describes a new version of a reactivity meter developed at the Institute of Nuclear Energy Research (IPEN) (Brazil). The reactivity meter computes the reactor reactivity utilizing a programmable electrometer that performs the data aquisition. The software commands the main functions of the electrometer, the data acquisition, data transfer, and reactivity calculation. The necessary hardware for this reactivity meter are a programmable electrometer, a microcomputer, and interfaces for the microcomputer to communicate with the electrometer. If it is necessary, it is possible to connect a graphic register to the microcomputer. With this conventional hardware, available in any nuclear reactor facility, one can build a powerful reactivity meter. Adding to these advantages, one can use the microcomputer on-line to analyze the data, store the data on diskettes, or create graphics

C-Reactive Protein Levels in the Brugada Syndrome

Directory of Open Access Journals (Sweden)

Aimé Bonny

2011-01-01

Full Text Available Background. Inflammation in the Brugada syndrome (BrS and its clinical implication have been little studied. Aims. To assess the level of inflammation in BrS patients. Methods. All studied BrS patients underwent blood samples drawn for C-reactive protein (CRP levels at admission, prior to any invasive intervention. Patients with a previous ICD placement were controlled to exclude those with a recent (<14 days shock. We divided subjects into symptomatic (syncope or aborted sudden death and asymptomatic groups. In a multivariable analysis, we adjusted for significant variables (age, CRP ≥ 2 mg/L. Results. Fifty-four subjects were studied (mean age 45 ± 13 years, 49 (91% male. Twenty (37% were symptomatic. Baseline characteristics were similar in both groups. Mean CRP level was 1,4 ± 0,9 mg/L in asymptomatic and 2,4 ± 1,4 mg/L in symptomatic groups (P = .003. In the multivariate model, CRP concentrations ≥ 2 mg/L remained an independent marker for being symptomatic (P = .018; 95% CI: 1.3 to 19.3. Conclusion. Inflammation seems to be more active in symptomatic BrS. C-reactive protein concentrations ≥ 2 mg/L might be associated with the previous symptoms in BrS. The value of inflammation as a risk factor of arrhythmic events in BrS needs to be studied.

The composition dependence of the photochemical reactivity of strontium barium titanate

Science.gov (United States)

Bhardwaj, Abhilasha

, relative band edge positions and pH of the solution that can influence the reactivity. However, these factors are not significant in determining the composition dependence of the photochemical reactivity of SrxBa 1-xTiO3. The comparison of the surfaces of SrxBa 1-xTiO3 samples imaged by AFM after reaction (with silver nitrate) also showed that the mode of reaction gradually changes from spatially selective reactivity for BaTiO3 to spatially uniform reactivity for SrTiO3. The spatially selective reactivity disappears completely when x in SrxBa1-xTiO3 is greater than or equal to 0.28. The mechanism of the photochemical reaction of methylene blue dye on SrxBa1-xTiO3 was also studied. It is found that the dye reacts by a mechanism similar to that of silver. The methylene blue dye and silver reduce on the surfaces of positively charged domains and the reduced reaction products remain at the reduction reaction site. Extensions of this research would be to experimentally determine the band edges and defect concentrations in SrxBa1-xTiO 3 to get a better understanding of their influence on photochemical reactivity. Since the long term goal of this research is to find a efficient particulate catalyst for photocatalysis of water, the next step in this research is to carry out the photocatalysis of water using SrxBa1-x TiO3 powders. The effect of catalyst particle size should also be analyzed.

Separation of uranium and rare earth elements from Rirang ore leach solution by two-step precipitation

International Nuclear Information System (INIS)

Sradjono; Erni Rifandriyah, A.; Zahardi

1995-01-01

Separation of uranium and rare-earth elements from Rirang ore leach solution was carried out through a two-step precipitation. Several condition affecting the separation processes were examined including solution pH, reagent concentration, and reaction prepitation time. Optimum conditions for the first and second precipitation steps include adjustment of precipitation pH to 1.3 and 2.3, respectively by the addition of 7.3% of NH 4 OH solution and allowing 60 minutes precipitation/reaction time. Based on the conditions, about 6% of Th, 3% of U, 0.9% of PO 4 3- , and none of RE were recovered in the first precipitation step meanwhile, about 99% of RE, 55% of U, 76% of PO 4 3- , and of the Th were recovered in the second step. (author). 3 refs. 4 tabs. 4 figs

A step-defined sedentary lifestyle index: <5000 steps/day.

Science.gov (United States)

Tudor-Locke, Catrine; Craig, Cora L; Thyfault, John P; Spence, John C

2013-02-01

Step counting (using pedometers or accelerometers) is widely accepted by researchers, practitioners, and the general public. Given the mounting evidence of the link between low steps/day and time spent in sedentary behaviours, how few steps/day some populations actually perform, and the growing interest in the potentially deleterious effects of excessive sedentary behaviours on health, an emerging question is "How many steps/day are too few?" This review examines the utility, appropriateness, and limitations of using a reoccurring candidate for a step-defined sedentary lifestyle index: 10 000) to lower (sedentary lifestyle index for adults is appropriate for researchers and practitioners and for communicating with the general public. There is little evidence to advocate any specific value indicative of a step-defined sedentary lifestyle index in children and adolescents.

The Relations of Temperament Reactivity and Effortful Control to Children’s Adjustment Problems in China and the United States

Science.gov (United States)

Zhou, Qing; Lengua, Liliana J.; Wang, Yun

2014-01-01

The relations of parents’ and teachers’ reports of temperament anger-irritability, positive emotionality, and effortful control (attention focusing and inhibitory control) to children’s externalizing and internalizing problems were examined in Chinese (N = 382) and U.S. (N = 322) samples of school-age children. Results suggested that in both cultures, low effortful control and high anger–irritability were associated with high externalizing problems, although the relations were stronger in the Chinese sample than in the U.S. sample. Low positive emotionality was associated with high internalizing problems in both cultures. However, high positive emotionality was associated with noncomorbid externalizing problems (teachers’ reports) in the Chinese sample but not in the U.S. sample. These findings suggest that there are considerable cross-cultural similarities in the temperament-adjustment associations, although some cross-cultural differences might exist. Implications of the findings for the detection and intervention of adjustment problems in Chinese children are discussed. PMID:19413428

Sex-specific effects of mindfulness on romantic partners' cortisol responses to conflict and relations with psychological adjustment.

Science.gov (United States)

Laurent, Heidemarie; Laurent, Sean; Hertz, Robin; Egan-Wright, Dorianne; Granger, Douglas A

2013-12-01

Mindfulness is known to improve individuals' and couples' subjective stress regulation, but little is known about how it impacts hypothalamic-pituitary-adrenal (HPA) axis responses to acute psychosocial stress. The current study tested effects of dispositional mindfulness facets on young adult couples' cortisol responses to a conflict discussion stressor, as well as associations with psychological adjustment. One hundred heterosexual couples completed the five facet mindfulness questionnaire one week before engaging in a conflict discussion task. Each partner provided five saliva samples from pre- to post-conflict, which were assayed for cortisol. Measures of adjustment - depression and anxiety symptoms and global well-being - were also completed at this session. Hierarchical linear modeling of cortisol trajectories revealed sex-specific effects; whereas women's mindfulness (nonreactivity facet) predicted higher conflict stress cortisol levels, men's mindfulness (describing facet) predicted less pronounced cortisol reactivity/recovery curves. These patterns were related to better adjustment-lower depression symptoms for women and greater well-being for men. Implications for sex differences in mindfulness benefits are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

39 CFR 3010.25 - Limitation on unused rate adjustment authority rate adjustments.

Science.gov (United States)

2010-07-01

... only be applied together with inflation-based limitation rate adjustments or when inflation-based... used in lieu of an inflation-based limitation rate adjustment. ... 39 Postal Service 1 2010-07-01 2010-07-01 false Limitation on unused rate adjustment authority...

Potential impact of reactive vaccination in controlling cholera outbreaks: an exploratory analysis using a Zimbabwean experience.

Science.gov (United States)

Kim, Sun-Young; Choi, Yeongchull; Mason, Peter R; Rusakaniko, Simbarashe; Goldie, Sue J

2011-09-05

To contain ongoing cholera outbreaks, the World Health Organization has suggested that reactive vaccination should be considered in addition to its previous control measures. To explore the potential impact of a hypothetical reactive oral cholera vaccination using the example of the recent large-scale cholera outbreak in Zimbabwe. This was a retrospective cost-effectiveness analysis calculating the health and economic burden of the cholera outbreak in Zimbabwe with and without reactive vaccination. The primary outcome measure was incremental cost per disability-adjusted life year (DALY) averted. Under the base-case assumptions (assuming 50% coverage among individuals aged ≥2 years), reactive vaccination could have averted 1 320 deaths and 23 650 DALYs. Considering herd immunity, the corresponding values would have been 2 920 deaths and 52 360 DALYs averted. The total vaccination costs would have been ~$74 million and ~$21 million, respectively, with per-dose vaccine price of US$5 and $1. The incremental costs per DALY averted of reactive vaccination were $2 770 and $370, respectively, for vaccine price set at $5 and $1. Assuming herd immunity, the corresponding cost was $980 with vaccine price of $5, and the programme was cost-saving with a vaccine price of $1. Results were most sensitive to case-fatality rate, per-dose vaccine price, and the size of the outbreak. Reactive vaccination has the potential to be a cost-effective measure to contain cholera outbreaks in countries at high risk. However, the feasibility of implementation should be further evaluated, and caution is warranted in extrapolating the findings to different settings in the absence of other in-depth studies.

Fitting method of pseudo-polynomial for solving nonlinear parametric adjustment

Institute of Scientific and Technical Information of China (English)

陶华学; 宫秀军; 郭金运

2001-01-01

The optimal condition and its geometrical characters of the least-square adjustment were proposed. Then the relation between the transformed surface and least-squares was discussed. Based on the above, a non-iterative method, called the fitting method of pseudo-polynomial, was derived in detail. The final least-squares solution can be determined with sufficient accuracy in a single step and is not attained by moving the initial point in the view of iteration. The accuracy of the solution relys wholly on the frequency of Taylor's series. The example verifies the correctness and validness of the method.

Astronomical sketching a step-by-step introduction

CERN Document Server

Handy, Richard; Perez, Jeremy; Rix, Erika; Robbins, Sol

2007-01-01

This book presents the amateur with fine examples of astronomical sketches and step-by-step tutorials in each medium, from pencil to computer graphics programs. This unique book can teach almost anyone to create beautiful sketches of celestial objects.

Calculation-measurement comparison for control rods reactivity in RA-3 nuclear reactor

International Nuclear Information System (INIS)

Estryk, Guillermo; Gomez, Angel

2002-01-01

The RA-3 Nuclear Reactor of the Atomic Energy National Commission from Argentina, begun working with high enrichment fuel elements in 1967, and turned to low enrichment by 1990. During 1999 it was found out that several fuel elements had problems, so more than 50 % of them had to be removed from the core. Because of this, it was planned to go from core 93 to core 94 with special care from nuclear safety point of view. Core 94 was preceded by other five, T-1 to T-5, only as transitory ones. The care implied several nuclear parameters measurements: core reactivity excess, calibration of control rods, etc. Calculations were performed afterwards to simulate those measurements using the neutron diffusion code PUMA. The comparison shows a good agreement for more than 80% of the cases with differences lower than 10% in reactivity. The greatest differences were found in the last part of the control rods calibration and a better calculation of cell constants is planned to be done in order to improve the adjustment. (author)

Reactive Programming in Java

CERN Document Server

CERN. Geneva

2017-01-01

Reactive Programming in gaining a lot of excitement. Many libraries, tools, and frameworks are beginning to make use of reactive libraries. Besides, applications dealing with big data or high frequency data can benefit from this programming paradigm. Come to this presentation to learn about what reactive programming is, what kind of problems it solves, how it solves them. We will take an example oriented approach to learning the programming model and the abstraction.

Phosphonic acids aid composition adjustment in the synthesis of Cu_2_+_xZn_1_−_xSnSe_4_−_y nanoparticles

International Nuclear Information System (INIS)

Ibáñez, Maria; Berestok, Taisiia; Dobrozhan, Oleksandr; LaLonde, Aaron; Izquierdo-Roca, Victor; Shavel, Alexey; Pérez-Rodríguez, Alejandro; Snyder, G. Jeffrey; Cabot, Andreu

2016-01-01

The functional properties of quaternary I_2–II–IV–VI_4 nanomaterials, with potential interest in various technological fields, are highly sensitive to compositional variations, which is a challenging parameter to adjust. Here we demonstrate the presence of phosphonic acids to aid controlling the reactivity of the II element monomer to be incorporated in quaternary Cu_2ZnSnSe_4 nanoparticles and thus to provide a more reliable way to adjust the final nanoparticle metal ratios. Furthermore, we demonstrate the composition control in such multivalence nanoparticles to allow modifying charge carrier concentrations in nanomaterials produced from the assembly of these building blocks.

Reactivity estimation during a reactivity-initiated accident using the extended Kalman filter

International Nuclear Information System (INIS)

Busquim e Silva, R.; Marques, A.L.F.; Cruz, J.J.; Shirvan, K.; Kazimi, M.S.

2015-01-01

Highlights: • The EKF is modeled using sophisticate strategies to make the algorithm robust and accurate. • For a supercritical reactor under RIA, the EKF presents better results compared to IPK method independent of magnitude of the noise loads. • A sensitivity for five distinct carry-over effects indicates that the EKF is less sensitive to the different set of noise. • Although the P3D/R5 simulates the reactivity using a spatial kinetics method, the use of PKRE to model the EKF provides accurate results. • The reactivity’s standard deviation is higher for the IKF method. • Under HZP (slow power response) the IPK reactivity varies widely from positive to negative values (add extra difficulty to controlling the supercritical reactor): the EKF method does not have similar behavior under the same conditions (better controlling the operation). - Abstract: This study implements the extended Kalman filter (EKF) to estimate the nuclear reactor reactivity behavior under a reactivity-initiated accident (RIA). A coupled neutronics/thermal hydraulics code PARCS/RELAP5 (P3D/R5) simulates a control rod assembly ejection (CRE) on a traditional 2272 MWt PWR to generate the reactor power profile. A MATLAB script adds random noise to the simulated reactor power. For comparison, the inverse point kinetics (IPK) deterministic method is also implemented. Three different cases of CRE are simulated and the EKF, IPK and the P3D/R5 reactivity are compared. It was found that the EKF method presents better results compared to the IPK method. Furthermore, under a RIA due to small reactivity insertion and slow power response, the IPK reactivity varies widely from positive to negative, which may add extra difficulty to the task of controlling a supercritical reactor. This feature is also confirmed by a sensitivity analysis for five different noise loads and three distinct noise measurements standard deviations (SD)

Regarding KUR Reactivity Measurement System

International Nuclear Information System (INIS)

Nakamori, Akira; Hasegawa, Kei; Tsuchiyama, Tatsuo; Yamamoto, Toshihiro; Okumura, Ryo; Sano, Tadafumi

2012-01-01

This article reported: (1) the outline of the reactivity measurement system of Kyoto University Research Reactor (KUR), (2) the calibration data of control rod, (3) the problems and the countermeasures for range switching of linear output meter. For the laptop PC for the reactivity measurement system, there are four input signals: (1) linear output meter, (2) logarithmic output meter, (3) core temperature gauge, and (4) control rod position. The hardware of reactivity measurement system is controlled with Labview installed on the laptop. Output, reactivity, reactor period, and the change in reactivity due to temperature effect or Xenon effect are internally calculated and displayed in real-time with Labview based on the four signals above. Calculation results are recorded in the form of a spreadsheet. At KUR, the reactor core arrangement was changed, so the control rod was re-calibrated. At this time, calculated and experimental values of reactivity based on the reactivity measurement system were compared, and it was confirmed that the reactivity calculation by Labview was accurate. The range switching of linear output meter in the nuclear instrumentation should automatically change within the laptop, however sometimes this did not function properly in the early stage. It was speculated that undefined percent values during the transition of percent value were included in the calculation and caused calculation errors. The range switching started working properly after fixing this issue. (S.K.)

One step beyond: Different step-to-step transitions exist during continuous contact brachiation in siamangs

Directory of Open Access Journals (Sweden)

Fana Michilsens

2012-02-01

In brachiation, two main gaits are distinguished, ricochetal brachiation and continuous contact brachiation. During ricochetal brachiation, a flight phase exists and the body centre of mass (bCOM describes a parabolic trajectory. For continuous contact brachiation, where at least one hand is always in contact with the substrate, we showed in an earlier paper that four step-to-step transition types occur. We referred to these as a ‘point’, a ‘loop’, a ‘backward pendulum’ and a ‘parabolic’ transition. Only the first two transition types have previously been mentioned in the existing literature on gibbon brachiation. In the current study, we used three-dimensional video and force analysis to describe and characterize these four step-to-step transition types. Results show that, although individual preference occurs, the brachiation strides characterized by each transition type are mainly associated with speed. Yet, these four transitions seem to form a continuum rather than four distinct types. Energy recovery and collision fraction are used as estimators of mechanical efficiency of brachiation and, remarkably, these parameters do not differ between strides with different transition types. All strides show high energy recoveries (mean  = 70±11.4% and low collision fractions (mean  = 0.2±0.13, regardless of the step-to-step transition type used. We conclude that siamangs have efficient means of modifying locomotor speed during continuous contact brachiation by choosing particular step-to-step transition types, which all minimize collision fraction and enhance energy recovery.

Physics characteristics of a CANDU-600 with repositional adjuster rods fuelled with MOX or natural uranium

International Nuclear Information System (INIS)

Boczar, P.G.

1985-06-01

Repositioning the adjuster rods in 4 axial banks in future CANDU-600 reactors would permit the flexibility of grading the inner and outer banks to achieve optimal flattening of the axial power distribution for any particular fuel. With the 4 banks identical, acceptable axial power profiles can be achieved for both MOX and natural uranium fuels. Future work is to be directed at assessing the impact of lower zone controller and shutoff rod worth in the configuration of reactivity devices considered here, and if necessary, in identifying means of increasing their worth

Cardiovascular reactivity and proactive and reactive relational aggression among women with and without a history of sexual abuse.

Science.gov (United States)

Murray-Close, Dianna; Rellini, Alessandra H

2012-01-01

This study examined the association between cardiovascular reactivity and proactive and reactive functions of relational aggression among women with and without a history of sexual abuse. Heart rate reactivity, blood pressure reactivity, and respiratory sinus arrhythmia reactivity while recounting a relational stressor (e.g., being left out) were assessed. Participants provided self-reports of relational aggression and a history of sexual abuse prior to age 16. Results indicated that cardiovascular reactivity was only associated with relational aggression among women with a history of sexual abuse. In addition, whereas blunted reactivity was associated with proactive relational aggression, exaggerated reactivity was associated with reactive relational aggression. These findings highlight the importance of considering contextual moderators of the association between cardiovascular reactivity and aggression; moreover, results highlight distinct cardiovascular correlates of different functions of aggression. Finally, the findings underscore the need for additional research examining the physiological correlates of aggressive behavior among women. Copyright © 2011 Elsevier B.V. All rights reserved.

Application of stepping motor

International Nuclear Information System (INIS)

1980-10-01

This book is divided into three parts, which is about practical using of stepping motor. The first part has six chapters. The contents of the first part are about stepping motor, classification of stepping motor, basic theory og stepping motor, characteristic and basic words, types and characteristic of stepping motor in hybrid type and basic control of stepping motor. The second part deals with application of stepping motor with hardware of stepping motor control, stepping motor control by microcomputer and software of stepping motor control. The last part mentions choice of stepping motor system, examples of stepping motor, measurement of stepping motor and practical cases of application of stepping motor.

A simultaneous modulation of reactive and proactive inhibition processes by anodal tDCS on the right inferior frontal cortex.

Directory of Open Access Journals (Sweden)

Toni Cunillera

Full Text Available Proactive and reactive inhibitory processes are a fundamental part of executive functions, allowing a person to stop inappropriate responses when necessary and to adjust performance in in a long term in accordance to the goals of a task. In the current study, we manipulate, in a single task, both reactive and proactive inhibition mechanisms, and we investigate the within-subjects effect of increasing, by means of anodal transcranial direct current stimulation (tDCS, the involvement of the right inferior frontal cortex (rIFC. Our results show a simultaneous enhancement of these two cognitive mechanisms when modulating the neural activity of rIFC. Thus, the application of anodal tDCS increased reaction times on Go trials, indicating a possible increase in proactive inhibition. Concurrently, the stop-signal reaction time, as a covert index of the inhibitory process, was reduced, demonstrating an improvement in reactive inhibition. In summary, the current pattern of results validates the engagement of the rIFC in these two forms of inhibitory processes, proactive and reactive inhibition and it provides evidence that both processes can operate concurrently in the brain.

Internship guide : Work placements step by step

NARCIS (Netherlands)

Haag, Esther

2013-01-01

Internship Guide: Work Placements Step by Step has been written from the practical perspective of a placement coordinator. This book addresses the following questions : what problems do students encounter when they start thinking about the jobs their degree programme prepares them for? How do you

Microsoft Office professional 2010 step by step

CERN Document Server

Cox, Joyce; Frye, Curtis

2011-01-01

Teach yourself exactly what you need to know about using Office Professional 2010-one step at a time! With STEP BY STEP, you build and practice new skills hands-on, at your own pace. Covering Microsoft Word, PowerPoint, Outlook, Excel, Access, Publisher, and OneNote, this book will help you learn the core features and capabilities needed to: Create attractive documents, publications, and spreadsheetsManage your e-mail, calendar, meetings, and communicationsPut your business data to workDevelop and deliver great presentationsOrganize your ideas and notes in one placeConnect, share, and accom

Benchmark on traveling wave fast reactor with negative reactivity feedback obtained with MCNPX code

International Nuclear Information System (INIS)

Gann, V.V.; Gann, A.V.

2012-01-01

This paper presents results of computer simulations of traveling wave fast reactor with negative reactivity feedback. The results were obtained using MCNPX code combined with CINDER90 subroutine for depletion calculations. We considered 1-D model of TWR containing 4 m long core made of mixture of 66 at. % 238 U and 34 at. % 10 B. Ignitor made of 235 U was located in the center of the core. Boron was included as imitator of structural in-core materials and coolant. Negative reactivity feedback was adjusted to reactor power of 500 MW. In this case two burning waves originated from the igniter and travel to the ends of the core during the following 40 years; coefficient of utilization of 238 U reached 80 %. Distribution of specific power in traveling wave, isotope concentration of fission products and actinides, neutron flux, fast neutron spectrum, specific activity were calculated. Data of the computer simulation is in qualitative agreement with theoretical results obtained in slow burning wave approximation

Annual Adjustment Factors

Data.gov (United States)

Department of Housing and Urban Development — The Department of Housing and Urban Development establishes the rent adjustment factors - called Annual Adjustment Factors (AAFs) - on the basis of Consumer Price...

Control of the optical properties of silicon and chromium mixed oxides deposited by reactive magnetron sputtering

International Nuclear Information System (INIS)

Vergara, L.; Galindo, R. Escobar; Martinez, R.; Sanchez, O.; Palacio, C.; Albella, J.M.

2011-01-01

The development of mixed-oxide thin films allows obtaining materials with better properties than those of the different binary oxides, which makes them suitable for a great number of applications in different fields, such as tribology, optics or microelectronics. In this paper we investigate the deposition of mixed chromium and silicon oxides deposited by reactive magnetron sputtering with a view to use them as optical coatings with an adjustable refractive index. These films have been characterized by means of Rutherford backscattering spectrometry, Auger electron spectroscopy, X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy and spectroscopic ellipsometry so as to determine how the deposition conditions influence the characteristics of the material. We have found that the deposition parameter whose influence determines the properties of the films to a greater extent is the amount of oxygen in the reactive sputtering gas.

Intersectional scholarship & positive youth development: Post-modern paradigm shift in understanding adjustment of marginalized youth

Directory of Open Access Journals (Sweden)

J.-M. GONZALEZ

2016-11-01

Full Text Available Research on intersectionality of marginalized youth is generally situated in the assumption that non-normative identity leads to pathology and victimization. Further, most research to date has studied marginalized youth using a traditional nuclear family paradigm. In this paper we discuss how intersectionality addresses the combination of strengths and challenges of living with stigmatizing identities and family processes, towards developing successful youth adjustment. We apply the three-step intersectionality approach to study findings among a group of racial/ethnic minority and sexual minority identified youth and discuss the particular role of familism and extended kinship support beliefs that are unique to these youth as a promoter of successful adjustment.

[Hyper-reactive malarial splenomegaly].

Science.gov (United States)

Maazoun, F; Deschamps, O; Barros-Kogel, E; Ngwem, E; Fauchet, N; Buffet, P; Froissart, A

2015-11-01

Hyper-reactive malarial splenomegaly is a rare and severe form of chronic malaria. This condition is a common cause of splenomegaly in endemic areas. The pathophysiology of hyper-reactive malarial splenomegaly involves an intense immune reaction (predominantly B cell-driven) to repeated/chronic infections with Plasmodium sp. The diagnosis may be difficult, due to a poorly specific clinical presentation (splenomegaly, fatigue, cytopenias), a long delay between residence in a malaria-endemic area and onset of symptoms, and a frequent absence of parasites on conventional thin and thick blood smears. A strongly contributive laboratory parameter is the presence of high levels of total immunoglobulin M. When the diagnostic of hyper-reactive malarial splenomegaly is considered, search for anti-Plasmodium antibodies and Plasmodium nucleic acids (genus and species) by PCR is useful. Diagnosis of hyper-reactive malarial splenomegaly relies on the simultaneous presence of epidemiological, clinical, biological and follow-up findings. Regression of both splenomegaly and hypersplenism following antimalarial therapy allows the differential diagnosis with splenic lymphoma, a common complication of hyper-reactive malarial splenomegaly. Although rare in Western countries, hyper-reactive malarial splenomegaly deserves increased medical awareness to reduce the incidence of incorrect diagnosis, to prevent progression to splenic lymphoma and to avoid splenectomy. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

A high resolution pneumatic stepping actuator for harsh reactor environments

Science.gov (United States)

Tippetts, Thomas B.; Evans, Paul S.; Riffle, George K.

1993-01-01

A reactivity control actuator for a high-power density nuclear propulsion reactor must be installed in close proximity to the reactor core. The energy input from radiation to the actuator structure could exceed hundreds of W/cc unless low-cross section, low-absorptivity materials are chosen. Also, for post-test handling and subsequent storage, materials should not be used that are activated into long half-life isotopes. Pneumatic actuators can be constructed from various reactor-compatible materials, but conventional pneumatic piston actuators generally lack the stiffness required for high resolution reactivity control unless electrical position sensors and compensated electronic control systems are used. To overcome these limitations, a pneumatic actuator is under development that positions an output shaft in response to a series of pneumatic pulses, comprising a pneumatic analog of an electrical stepping motor. The pneumatic pulses are generated remotely, beyond the strong radiation environment, and transmitted to the actuator through tubing. The mechanically simple actuator uses a nutating gear harmonic drive to convert motion of small pistons directly to high-resolution angular motion of the output shaft. The digital nature of this actuator is suitable for various reactor control algorithms but is especially compatible with the three bean salad algorithm discussed by Ball et al. (1991).

Innovation of High Voltage Supply Adjustment Device on Diagnostic X-Ray Machine

International Nuclear Information System (INIS)

Sujatno; Wiranto Budi Santoso

2010-01-01

Innovation of high voltage supply adjustment device on diagnostic x-ray machine has been carried out. The innovation is conducted by utilizing an electronic circuit as a high voltage adjustment device. Usually a diagnostic x-ray machine utilizes a transformer or an auto-transformer as a high voltage supply adjustment device. A high power diagnostic x-ray machine needs a high power transformer which has big physical dimension. Therefore a box control where the transformer is located has to have big physical dimension. Besides, the price of the transformer is expensive and hardly found in local markets. In this innovation, the transformer is replaced by an electronic circuit. The main component of the electronic circuit is Triac BTA-40. As adjustment device, the triac is controlled by a variable resistor which is coupled by a stepper motor. A step movement of stepper motor varies a value of resistor. The resistor value determines the triac gate voltage. Furthermore the triac will open according to the value of electrical current flowing to the gate. When the gate is open, electrical voltage and current will flow from cathode to anode of the triac. The value of these electrical voltage and current depend on gate open condition. Then this triac output voltage is feed to diagnostic x-ray machine high voltage supply. Therefore the high voltage value of diagnostic x-ray machine is adjusted by the output voltage of the electronic circuit. By using this electronic circuit, the physical dimension of diagnostic x-ray machine box control and the price of the equipment can be reduced. (author)

Convexity Adjustments for ATS Models

DEFF Research Database (Denmark)

Murgoci, Agatha; Gaspar, Raquel M.

. As a result we classify convexity adjustments into forward adjustments and swaps adjustments. We, then, focus on affine term structure (ATS) models and, in this context, conjecture convexity adjustments should be related of affine functionals. In the case of forward adjustments, we show how to obtain exact...

Elaboration of titanium nitride coatings by activated reactive evaporation

International Nuclear Information System (INIS)

Granier, Jean

1978-01-01

As titanium nitride is a very interesting and promising material for the protection against wear and corrosion of metals and alloys with a low fusion point, and notably steels, this research thesis reports the study of the elaboration of a TiN coating by activated reactive evaporation. In a first part, the author describes deposition processes based on evaporation and their characteristics. He explains the choice of the studied process. He discusses published data and results related to the titanium-nitrogen system. He describes the apparatus and reports the operation mode adjustment, and reports the study of the influence of operating conditions (substrate temperature, nitrogen pressure, evaporation rate, possible use of a discharge) on growth kinetics and on coating properties. A reaction mechanism is then proposed to describe and explain the obtained results [fr

Development of a three dimensional homogeneous calculation model for the BFS-62 critical experiment. Preparation of adjusted equivalent measured values for sodium void reactivity values. Final report

International Nuclear Information System (INIS)

Manturov, G.; Semenov, M.; Seregin, A.; Lykova, L.

2004-01-01

The BFS-62 critical experiments are currently used as 'benchmark' for verification of IPPE codes and nuclear data, which have been used in the study of loading a significant amount of Pu in fast reactors. The BFS-62 experiments have been performed at BFS-2 critical facility of IPPE (Obninsk). The experimental program has been arranged in such a way that the effect of replacement of uranium dioxied blanket by the steel reflector as well as the effect of replacing UOX by MOX on the main characteristics of the reactor model was studied. Wide experimental program, including measurements of the criticality-keff, spectral indices, radial and axial fission rate distributions, control rod mock-up worth, sodium void reactivity effect SVRE and some other important nuclear physics parameters, was fulfilled in the core. Series of 4 BFS-62 critical assemblies have been designed for studying the changes in BN-600 reactor physics from existing state to hybrid core. All the assemblies are modeling the reactor state prior to refueling, i.e. with all control rod mock-ups withdrawn from the core. The following items are chosen for the analysis in this report: Description of the critical assembly BFS-62-3A as the 3rd assembly in a series of 4 BFS critical assemblies studying BN-600 reactor with MOX-UOX hybrid zone and steel reflector; Development of a 3D homogeneous calculation model for the BFS-62-3A critical experiment as the mock-up of BN-600 reactor with hybrid zone and steel reflector; Evaluation of measured nuclear physics parameters keff and SVRE (sodium void reactivity effect); Preparation of adjusted equivalent measured values for keff and SVRE. Main series of calculations are performed using 3D HEX-Z diffusion code TRIGEX in 26 groups, with the ABBN-93 cross-section set. In addition, precise calculations are made, in 299 groups and Ps-approximation in scattering, by Monte-Carlo code MMKKENO and discrete ordinate code TWODANT. All calculations are based on the common system

A New Approach to Optimal Allocation of Reactive Power Ancillary Service in Distribution Systems in the Presence of Distributed Energy Resources

Directory of Open Access Journals (Sweden)

Abouzar Samimi

2015-11-01

Full Text Available One of the most important Distribution System Operators (DSO schemes addresses the Volt/Var control (VVC problem. Developing a cost-based reactive power dispatch model for distribution systems, in which the reactive powers are appropriately priced, can motivate Distributed Energy Resources (DERs to participate actively in VVC. In this paper, new reactive power cost models for DERs, including synchronous machine-based DGs and wind turbines (WTs, are formulated based on their capability curves. To address VVC in the context of competitive electricity markets in distribution systems, first, in a day-ahead active power market, the initial active power dispatch of generation units is estimated considering environmental and economic aspects. Based on the results of the initial active power dispatch, the proposed VVC model is executed to optimally allocate reactive power support among all providers. Another novelty of this paper lies in the pricing scheme that rewards transformers and capacitors for tap and step changing, respectively, while incorporating the reactive power dispatch model. A Benders decomposition algorithm is employed as a solution method to solve the proposed reactive power dispatch, which is a mixed integer non-linear programming (MINLP problem. Finally, a typical 22-bus distribution network is used to verify the efficiency of the proposed method.

Reactive solute transport in physically and chemically heterogeneous porous media with multimodal reactive mineral facies: the Lagrangian approach.

Science.gov (United States)

Soltanian, Mohamad Reza; Ritzi, Robert W; Dai, Zhenxue; Huang, Chao Cheng

2015-03-01

Physical and chemical heterogeneities have a large impact on reactive transport in porous media. Examples of heterogeneous attributes affecting reactive mass transport are the hydraulic conductivity (K), and the equilibrium sorption distribution coefficient (Kd). This paper uses the Deng et al. (2013) conceptual model for multimodal reactive mineral facies and a Lagrangian-based stochastic theory in order to analyze the reactive solute dispersion in three-dimensional anisotropic heterogeneous porous media with hierarchical organization of reactive minerals. An example based on real field data is used to illustrate the time evolution trends of reactive solute dispersion. The results show that the correlation between the hydraulic conductivity and the equilibrium sorption distribution coefficient does have a significant effect on reactive solute dispersion. The anisotropy ratio does not have a significant effect on reactive solute dispersion. Furthermore, through a sensitivity analysis we investigate the impact of changing the mean, variance, and integral scale of K and Kd on reactive solute dispersion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Experimental estimation of moderator temperature coefficient of reactivity of the IPEN/MB-01 research reactor

International Nuclear Information System (INIS)

Silva, Rubens C. da; Bitelli, Ulysses D.; Mura, Luiz Ernesto C.

2017-01-01

The aim of this article is to present the procedure for the experimental estimation of the Moderator Temperature Coefficient of Reactivity of the IPEN/MB-01 Research Reactor, a parameter that has an important role in the physics and the control operations of any reactor facility. At the experiment, the IPEN/MB-01 reactor went critical at the power of 1W (1% of its total power), and whose core configuration was 28 x 26 rectangular array of UO_2 fuel rods, inside a light water (moderator) tank. In addition, there was a heavy water (D_2O) reflector installed in the West side of the core to obtain an adequate neutron reflection along the experiment. The moderator temperature was increased in steps of 4 °C, and the measurement of the mean moderator temperature was acquired using twelve calibrated thermocouples, placed around the reactor core. As a result, the mean value of -4.81 pcm/°C was obtained for such coefficient. The curves of ρ(T) (Reactivity x Temperature) and α"M_T(T)(Moderator Temperature Coefficient of Reactivity x Temperature) were developed using data from an experimental measurement of the integral reactivity curves through the Stable Period and Inverse Kinetics Methods, that was carried out at the reactor with the same core configuration. Such curves were compared and showed a very similar behavior between them. (author)

Detection of Islet Cell Immune Reactivity with Low Glycemic Index Foods: Is This a Concern for Type 1 Diabetes?

Directory of Open Access Journals (Sweden)

Datis Kharrazian

2017-01-01

Full Text Available Dietary management of autoimmune diabetes includes low glycemic foods classified from the glycemic index, but it does not consider the role that immunoreactive foods may play with the immunological etiology of the disease. We measured the reactivity of either monoclonal or polyclonal affinity-purified antibodies to insulin, insulin receptor alpha, insulin receptor beta, zinc transporter 8 (ZnT8, tyrosine phosphatase-based islet antigen 2 (IA2, and glutamic acid decarboxylase (GAD 65 and 67 against 204 dietary proteins that are commonly consumed. Dietary protein determinants included unmodified (raw and modified (cooked and roasted foods, herbs, spices, food gums, brewed beverages, and additives. There was no immune reactivity between insulin or insulin receptor beta and dietary proteins. However, we identified strong to moderate immunological reactivity with antibodies against insulin receptor alpha, ZnT8, IA2, GAD-65, and GAD-67 with several dietary proteins. We also identified 49 dietary proteins found in foods classified as low glycemic foods with immune reactivity to autoimmune target sites. Laboratory analysis of immunological cross-reactivity between pancreas target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune diabetes.

Speech perception at positive signal-to-noise ratios using adaptive adjustment of time compression.

Science.gov (United States)

Schlueter, Anne; Brand, Thomas; Lemke, Ulrike; Nitzschner, Stefan; Kollmeier, Birger; Holube, Inga

2015-11-01

Positive signal-to-noise ratios (SNRs) characterize listening situations most relevant for hearing-impaired listeners in daily life and should therefore be considered when evaluating hearing aid algorithms. For this, a speech-in-noise test was developed and evaluated, in which the background noise is presented at fixed positive SNRs and the speech rate (i.e., the time compression of the speech material) is adaptively adjusted. In total, 29 younger and 12 older normal-hearing, as well as 24 older hearing-impaired listeners took part in repeated measurements. Younger normal-hearing and older hearing-impaired listeners conducted one of two adaptive methods which differed in adaptive procedure and step size. Analysis of the measurements with regard to list length and estimation strategy for thresholds resulted in a practical method measuring the time compression for 50% recognition. This method uses time-compression adjustment and step sizes according to Versfeld and Dreschler [(2002). J. Acoust. Soc. Am. 111, 401-408], with sentence scoring, lists of 30 sentences, and a maximum likelihood method for threshold estimation. Evaluation of the procedure showed that older participants obtained higher test-retest reliability compared to younger participants. Depending on the group of listeners, one or two lists are required for training prior to data collection.

Effect of nitrite, limited reactive settler and plant design configuration on the predicted performance of simultaneous C/N/P removal WWTPs

DEFF Research Database (Denmark)

Guerrero, Javier; Flores-Alsina, Xavier; Guisasola, Albert

2013-01-01

as the reference model (A1). The second case (A2) adds nitrite as a new state variable, describing nitrification and denitrification as two-step processes. The third set of models (A3 and A4) considers different reactive settlers types (diffusion-limited/non limited). This study analyses the importance...

Application of enhanced electronegative multimodal chromatography as the primary capture step for immunoglobulin G purification.

Science.gov (United States)

Wang, Yanli; Chen, Quan; Xian, Mo; Nian, Rui; Xu, Fei

2018-06-01

In recent studies, electronegative multimodal chromatography with Eshmuno HCX was demonstrated to be a highly promising recovery step for direct immunoglobulin G (IgG) capture from undiluted cell culture fluid. In this study, the binding properties of HCX to IgG at different pH/salt combinations were systematically studied, and its purification performance was significantly enhanced by lowering the washing pH and conductivity after high capacity binding of IgG under its optimal conditions. A single polishing step gave an end-product with non-histone host cell protein (nh-HCP) below 1 ppm, DNA less than 1 ppb, which aggregates less than 0.5% and an overall IgG recovery of 86.2%. The whole non-affinity chromatography based two-column-step process supports direct feed loading without buffer adjustment, thus extraordinarily boosting the overall productivity and cost-savings.

Maladaptive social information processing in childhood predicts young men's atypical amygdala reactivity to threat.

Science.gov (United States)

Choe, Daniel Ewon; Shaw, Daniel S; Forbes, Erika E

2015-05-01

Maladaptive social information processing, such as hostile attributional bias and aggressive response generation, is associated with childhood maladjustment. Although social information processing problems are correlated with heightened physiological responses to social threat, few studies have examined their associations with neural threat circuitry, specifically amygdala activation to social threat. A cohort of 310 boys participated in an ongoing longitudinal study and completed questionnaires and laboratory tasks assessing their social and cognitive characteristics the boys were between 10 and 12 years of age. At age 20, 178 of these young men underwent functional magnetic resonance imaging and a social threat task. At age 22, adult criminal arrest records and self-reports of impulsiveness were obtained. Path models indicated that maladaptive social information-processing at ages 10 and 11 predicted increased left amygdala reactivity to fear faces, an ambiguous threat, at age 20 while accounting for childhood antisocial behavior, empathy, IQ, and socioeconomic status. Exploratory analyses indicated that aggressive response generation - the tendency to respond to threat with reactive aggression - predicted left amygdala reactivity to fear faces and was concurrently associated with empathy, antisocial behavior, and hostile attributional bias, whereas hostile attributional bias correlated with IQ. Although unrelated to social information-processing problems, bilateral amygdala reactivity to anger faces at age 20 was unexpectedly predicted by low IQ at age 11. Amygdala activation did not mediate associations between social information processing and number of criminal arrests, but both impulsiveness at age 22 and arrests were correlated with right amygdala reactivity to anger facial expressions at age 20. Childhood social information processing and IQ predicted young men's amygdala response to threat a decade later, which suggests that childhood social

Blood Pressure Reactivity to Psychological Stress in Young Adults and Cognition in Midlife: The Coronary Artery Risk Development in Young Adults (CARDIA) Study.

Science.gov (United States)

Yano, Yuichiro; Ning, Hongyan; Reis, Jared P; Lewis, Cora E; Launer, Lenore J; Bryan, R Nick; Yaffe, Kristine; Sidney, Stephen; Albanese, Emiliano; Greenland, Philip; Lloyd-Jones, Donald; Liu, Kiang

2016-01-13

The classic view of blood pressure (BP) reactivity to psychological stress in relation to cardiovascular risks assumes that excess reactivity is worse and lower reactivity is better. Evidence addressing how stress-induced BP reactivity in young adults is associated with midlife cognitive function is sparse. We assessed BP reactivity during a star tracing task and a video game in adults aged 20 to 32 years. Twenty-three years later, cognitive function was assessed with use of the Digit Symbol Substitution Test (a psychomotor speed test), the Rey Auditory Verbal Learning Test (a verbal memory test), and the modified Stroop test (an executive function test). At the time of follow-up, participants (n=3021) had a mean age of 50.2 years; 56% were women, and 44% were black. In linear regression models adjusted for demographic and clinical characteristics including baseline and follow-up resting BP, lower systolic BP (SBP) reactivity during the star tracing and video game was associated with worse Digit Symbol Substitution Test scores (β [SE]: 0.11 [0.02] and 0.05 [0.02], respectively) and worse performance on the Stroop test (β [SE]: -0.06 [0.02] and -0.05 [0.02]; all Pstress-induced SBP reactivity in younger adults was associated with lower cognitive function in midlife. BP reactivity to psychological stressors may have different associations with target organs in hypertension. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

The way to collisions, step by step

CERN Multimedia

2009-01-01

While the LHC sectors cool down and reach the cryogenic operating temperature, spirits are warming up as we all eagerly await the first collisions. No reason to hurry, though. Making particles collide involves the complex manoeuvring of thousands of delicate components. The experts will make it happen using a step-by-step approach.

A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal

Energy Technology Data Exchange (ETDEWEB)

Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Lee, Dong-Weon, E-mail: mems@jnu.ac.kr [MEMS and Nanotechnology Laboratory, School of Mechanical Engineering, Chonnam National University, Gwangju 500757 (Korea, Republic of)

2015-12-15

This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10{sup −5} N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal

International Nuclear Information System (INIS)

Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Lee, Dong-Weon

2015-01-01

This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10"−"5 N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

The iodine reactivity

International Nuclear Information System (INIS)

2003-01-01

The iodine is an important element because it has long life isotopes (such as iodine 129) and a great mobility in natural media. Iodine presents a complex chemistry because of its volatility and its strong redox reactivity. The S.E.C.R. works to better understand the reactivity of this element in different natural, industrial or biological environments. It plays a part in thermochemical sites as a possible way of hydrogen formation. This seminar gives some aspects relative to the chemical reactivity of iodine, since its thermochemistry in the I/S cycles to produce hydrogen to its reactivity in the natural medium and its potential radiological impact. This document includes 4 presentations transparencies) dealing with: the 129 I cycle rejected in the low radioactive gaseous and liquid effluents of the La Hague reprocessing plant (C. Frechou); a bibliographic review of iodine retention in soils (F. Bazer-Bachi); the hydrogen production and the iodine/sulfur thermochemical cycle (role of iodine in the process); and the direct characterization by electro-spray ionization mass spectroscopy of iodine fixation by fulvic acids (P. Reiller, B. Amekraz, C. Moulin, V. Moulin)

Calculation of nuclear reactivity using the generalised Adams-Bashforth-Moulton predictor corrector method

Energy Technology Data Exchange (ETDEWEB)

Suescun-Diaz, Daniel [Surcolombiana Univ., Neiva (Colombia). Groupo de Fisica Teorica; Narvaez-Paredes, Mauricio [Javeriana Univ., Cali (Colombia). Groupo de Matematica y Estadistica Aplicada Pontificia; Lozano-Parada, Jamie H. [Univ. del Valle, Cali (Colombia). Dept. de Ingenieria

2016-03-15

In this paper, the generalisation of the 4th-order Adams-Bashforth-Moulton predictor-corrector method is proposed to numerically solve the point kinetic equations of the nuclear reactivity calculations without using the nuclear power history. Due to the nature of the point kinetic equations, different predictor modifiers are used in order improve the precision of the approximations obtained. The results obtained with the prediction formulas and generalised corrections improve the precision when compared with previous methods and are valid for various forms of nuclear power and different time steps.

High-Sensitivity C-Reactive Protein as a Predictor of Cardiovascular Events after ST-Elevation Myocardial Infarction

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Daniel Rios Pinto; Ramos, Adriane Monserrat; Vieira, Pedro Lima; Menti, Eduardo; Bordin, Odemir Luiz Jr.; Souza, Priscilla Azambuja Lopes de; Quadros, Alexandre Schaan de; Portal, Vera Lúcia, E-mail: veraportal.pesquisa@gmail.com [Programa de Pós-Graduação em Ciências da Saúde: Cardiologia - Instituto de Cardiologia/Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)

2014-07-15

The association between high-sensitivity C-reactive protein and recurrent major adverse cardiovascular events (MACE) in patients with ST-elevation myocardial infarction who undergo primary percutaneous coronary intervention remains controversial. To investigate the potential association between high-sensitivity C-reactive protein and an increased risk of MACE such as death, heart failure, reinfarction, and new revascularization in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention. This prospective cohort study included 300 individuals aged >18 years who were diagnosed with ST-elevation myocardial infarction and underwent primary percutaneous coronary intervention at a tertiary health center. An instrument evaluating clinical variables and the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores was used. High-sensitivity C-reactive protein was determined by nephelometry. The patients were followed-up during hospitalization and up to 30 days after infarction for the occurrence of MACE. Student's t, Mann-Whitney, chi-square, and logistic regression tests were used for statistical analyses. P values of ≤0.05 were considered statistically significant. The mean age was 59.76 years, and 69.3% of patients were male. No statistically significant association was observed between high-sensitivity C-reactive protein and recurrent MACE (p = 0.11). However, high-sensitivity C-reactive protein was independently associated with 30-day mortality when adjusted for TIMI [odds ratio (OR), 1.27; 95% confidence interval (CI), 1.07-1.51; p = 0.005] and GRACE (OR, 1.26; 95% CI, 1.06-1.49; p = 0.007) risk scores. Although high-sensitivity C-reactive protein was not predictive of combined major cardiovascular events within 30 days after ST-elevation myocardial infarction in patients who underwent primary angioplasty and stent implantation, it was an independent predictor

Development of numerical methods for reactive transport

International Nuclear Information System (INIS)

Bouillard, N.

2006-12-01

When a radioactive waste is stored in deep geological disposals, it is expected that the waste package will be damaged under water action (concrete leaching, iron corrosion). Then, to understand these damaging processes, chemical reactions and solutes transport are modelled. Numerical simulations of reactive transport can be done sequentially by the coupling of several codes. This is the case of the software platform ALLIANCES which is developed jointly with CEA, ANDRA and EDF. Stiff reactions like precipitation-dissolution are crucial for the radioactive waste storage applications, but standard sequential iterative approaches like Picard's fail in solving rapidly reactive transport simulations with such stiff reactions. In the first part of this work, we focus on a simplified precipitation and dissolution process: a system made up with one solid species and two aqueous species moving by diffusion is studied mathematically. It is assumed that a precipitation dissolution reaction occurs in between them, and it is modelled by a discontinuous kinetics law of unknown sign. By using monotonicity properties, the convergence of a finite volume scheme on admissible mesh is proved. Existence of a weak solution is obtained as a by-product of the convergence of the scheme. The second part is dedicated to coupling algorithms which improve Picard's method and can be easily used in an existing coupling code. By extending previous works, we propose a general and adaptable framework to solve nonlinear systems. Indeed by selecting special options, we can either recover well known methods, like nonlinear conjugate gradient methods, or design specific method. This algorithm has two main steps, a preconditioning one and an acceleration one. This algorithm is tested on several examples, some of them being rather academical and others being more realistic. We test it on the 'three species model'' example. Other reactive transport simulations use an external chemical code CHESS. For a

Global phenomena from local rules: Peer-to-peer networks and crystal steps

Science.gov (United States)

Finkbiner, Amy

Even simple, deterministic rules can generate interesting behavior in dynamical systems. This dissertation examines some real world systems for which fairly simple, locally defined rules yield useful or interesting properties in the system as a whole. In particular, we study routing in peer-to-peer networks and the motion of crystal steps. Peers can vary by three orders of magnitude in their capacities to process network traffic. This heterogeneity inspires our use of "proportionate load balancing," where each peer provides resources in proportion to its individual capacity. We provide an implementation that employs small, local adjustments to bring the entire network into a global balance. Analytically and through simulations, we demonstrate the effectiveness of proportionate load balancing on two routing methods for de Bruijn graphs, introducing a new "reversed" routing method which performs better than standard forward routing in some cases. The prevalence of peer-to-peer applications prompts companies to locate the hosts participating in these networks. We explore the use of supervised machine learning to identify peer-to-peer hosts, without using application-specific information. We introduce a model for "triples," which exploits information about nearly contemporaneous flows to give a statistical picture of a host's activities. We find that triples, together with measurements of inbound vs. outbound traffic, can capture most of the behavior of peer-to-peer hosts. An understanding of crystal surface evolution is important for the development of modern nanoscale electronic devices. The most commonly studied surface features are steps, which form at low temperatures when the crystal is cut close to a plane of symmetry. Step bunching, when steps arrange into widely separated clusters of tightly packed steps, is one important step phenomenon. We analyze a discrete model for crystal steps, in which the motion of each step depends on the two steps on either side of

Computation, measurement and analysis of the reactivity-to-power-transfer-function for the sodium cooled nuclear power plant KNK I

International Nuclear Information System (INIS)

Hoppe, P.; Mitzel, F.

1977-02-01

The Reactivity-to-Power-Transfer-Function for the sodium cooled nuclear power plant KNK I (Kompakte Natriumgekuehlte Kernenergieanlage) has been measured and compared with theoretical results. The measurements have been performed with the help of pseudostochastic reactivity perturbations. The transfer function has been determined by computing the auto- and cross-power-spectral-densities for the reactivity- and neutron flux signals. The agreement between the experimental and theoretical transfer function could be improved by adjusting the reactivity coefficients. The applications of these measurements with respect to reactor diagnosis and malfunction detection are discussed. For this purpose the accuracy of the measured transfer function is of great importance. Therefore an extensive error analysis has been performed. It turned out, that the inherent instability of the reactor without control system and the feedback by the primary coolant system were the reasons for comparatively big systematical errors. The conditions have been derived under which these types of errors can be considerably reduced. The conclusions can also be applied to analogical measurements at fast sodium cooled reactors. Because of their inherent stability the systematical errors will be reduced. (orig.) [de

Executive Functioning, Cortisol Reactivity, and Symptoms of Psychopathology in Girls with Premature Adrenarche

Science.gov (United States)

Sontag-Padilla, Lisa M.; Dorn, Lorah D.; Tissot, Abbigail; Susman, Elizabeth J.; Beers, Sue R.; Rose, Susan R.

2012-01-01

The study examined the interaction between early maturational timing [as measured by premature adrenarche (PA)] and executive functioning and cortisol reactivity on symptoms of psychopathology. The study included 76 girls aged 6 through 8 years (mean = 7.50; SD = .85) with PA (n = 40) and on-time adrenarche (n = 36). Girls completed a battery of psychological and neuropsychological tests and blood sampling for cortisol. Parents completed the Child Behavior Checklist. Results demonstrated that girls with PA with lower levels of executive functioning had higher externalizing and anxious symptoms compared to other girls. Additionally, girls with PA who demonstrated increases in serum cortisol had higher externalizing symptoms than those with stable patterns. Finally, girls with PA who demonstrated decreases in cortisol reported higher depressive symptoms. Findings from this study provide important information concerning the impact of cognitive functioning and stress reactivity on adjustment to early maturation in girls with PA. Results of this research may inform screening and intervention efforts for girls who may be at greatest risk for emotional and behavioral problems as a result of early maturation. PMID:22293005

Age-related changes in compensatory stepping in response to unpredictable perturbations.

Science.gov (United States)

McIlroy, W E; Maki, B E

1996-11-01

Recent studies highlight the importance of compensatory stepping to preserve stability, and the spatial and temporal demands placed on the control of this reaction. Age-related changes in the control of stepping could greatly influence the risk of falling. The present study compares, in healthy elderly and young adults, the characteristics of compensatory stepping responses to unpredictable postural perturbations. A moving platform was used to unpredictably perturb the upright stance of 14 naive, active and mobile subjects (5 aged 22 to 28 and 9 aged 65 to 81). The first 10 randomized trials (5 forward and 5 backward) were evaluated to allow a focus on reactions to relatively novel perturbations. The behavior of the subjects was not constrained. Forceplate and kinematic measures were used to evaluate the responses evoked by the brief (600 msec) platform translation. Subjects stepped in 98% of the trials. Although the elderly were less likely to execute a lateral anticipatory postural adjustment prior to foot-lift, the onset of swing-leg unloading tended to begin at the same time in the two age groups. There was remarkable similarity between the young and elderly in many other characteristics of the first step of the response. In spite of this similarity, the elderly subjects were twice as likely to take additional steps to regain stability (63% of trials for elderly). Moreover, in elderly subjects, the additional steps were often directed so as to preserve lateral stability, whereas the young rarely showed this tendency. Given the functional significance of base-of-support changes as a strategy for preserving stability and the age-related differences presently revealed, assessment of the capacity to preserve stability against unpredictable perturbation, and specific measures such as the occurrence or placement of multiple steps, may prove to be a significant predictor of falling risk and an important outcome in evaluating or developing intervention strategies to

Public Reporting of Primary Care Clinic Quality: Accounting for Sociodemographic Factors in Risk Adjustment and Performance Comparison.

Science.gov (United States)

Wholey, Douglas R; Finch, Michael; Kreiger, Rob; Reeves, David

2018-01-03

Performance measurement and public reporting are increasingly being used to compare clinic performance. Intended consequences include quality improvement, value-based payment, and consumer choice. Unintended consequences include reducing access for riskier patients and inappropriately labeling some clinics as poor performers, resulting in tampering with stable care processes. Two analytic steps are used to maximize intended and minimize unintended consequences. First, risk adjustment is used to reduce the impact of factors outside providers' control. Second, performance categorization is used to compare clinic performance using risk-adjusted measures. This paper examines the effects of methodological choices, such as risk adjusting for sociodemographic factors in risk adjustment and accounting for patients clustering by clinics in performance categorization, on clinic performance comparison for diabetes care, vascular care, asthma, and colorectal cancer screening. The population includes all patients with commercial and public insurance served by clinics in Minnesota. Although risk adjusting for sociodemographic factors has a significant effect on quality, it does not explain much of the variation in quality. In contrast, taking into account the nesting of patients within clinics in performance categorization has a substantial effect on performance comparison.

Stress Reactivity in Insomnia.

Science.gov (United States)

Gehrman, Philip R; Hall, Martica; Barilla, Holly; Buysse, Daniel; Perlis, Michael; Gooneratne, Nalaka; Ross, Richard J

2016-01-01

This study examined whether individuals with primary insomnia (PI) are more reactive to stress than good sleepers (GS). PI and GS (n = 20 per group), matched on gender and age, completed three nights of polysomnography. On the stress night, participants received a mild electric shock and were told they could receive additional shocks during the night. Saliva samples were obtained for analysis of cortisol and alpha amylase along with self-report and visual analog scales (VAS). There was very little evidence of increased stress on the stress night, compared to the baseline night. There was also no evidence of greater stress reactivity in the PI group for any sleep or for salivary measures. In the GS group, stress reactivity measured by VAS scales was positively associated with an increase in sleep latency in the experimental night on exploratory analyses. Individuals with PI did not show greater stress reactivity compared to GS.

Dissecting long-term adjustments of photoprotective and photo-oxidative stress acclimation occurring in dynamic light environments

Directory of Open Access Journals (Sweden)

Shizue Matsubara

2016-11-01

Full Text Available Changes in light intensity directly affect the performance of the photosynthetic apparatus. Light energy absorbed in excess of cells’ needs leads to production of reactive oxygen species and photo-oxidative damage. Excess light in both constant and dynamic environments induces photoprotective acclimation in plants. Distinct sets of signals and regulatory mechanisms are involved in acclimatory adjustment of photoprotection and photosynthesis under constant and dynamic (fluctuating light conditions. We are still far away from drawing a comprehensive picture of acclimatory signal transduction pathways, particularly in dynamic environments. In this perspective article, we propose the use of Arabidopsis plants that produce H2O2 in chloroplasts (GO plants under atmospheric CO2 levels as a tool to study the mechanisms of long-term acclimation to photo-oxidative stress. In our opinion there are new avenues to future investigations on acclimatory adjustments and signal transduction occurring in plants under dynamic light environments.

Metric-adjusted skew information

DEFF Research Database (Denmark)

Liang, Cai; Hansen, Frank

2010-01-01

on a bipartite system and proved superadditivity of the Wigner-Yanase-Dyson skew informations for such states. We extend this result to the general metric-adjusted skew information. We finally show that a recently introduced extension to parameter values 1 ...We give a truly elementary proof of the convexity of metric-adjusted skew information following an idea of Effros. We extend earlier results of weak forms of superadditivity to general metric-adjusted skew information. Recently, Luo and Zhang introduced the notion of semi-quantum states...... of (unbounded) metric-adjusted skew information....

ADJUSTABLE CHIP HOLDER

DEFF Research Database (Denmark)

2009-01-01

An adjustable microchip holder for holding a microchip is provided having a plurality of displaceable interconnection pads for connecting the connection holes of a microchip with one or more external devices or equipment. The adjustable microchip holder can fit different sizes of microchips...

Elementary Steps of Syngas Reactions on Mo2C(001): Adsorption Thermochemistry and Bond Dissociation

Energy Technology Data Exchange (ETDEWEB)

Medford, Andrew

2012-02-16

Density functional theory (DFT) and ab initio thermodynamics are applied in order to investigate the most stable surface and subsurface terminations of Mo{sub 2}C(001) as a function of chemical potential and in the presence of syngas. The Mo-terminated (001) surface is then used as a model surface to evaluate the thermochemistry and energetic barriers for key elementary steps in syngas reactions. Adsorption energy scaling relations and Broensted-Evans-Polanyi relationships are established and used to place Mo{sub 2}C into the context of transition metal surfaces. The results indicate that the surface termination is a complex function of reaction conditions and kinetics. It is predicted that the surface will be covered by either C{sub 2}H{sub 2} or O depending on conditions. Comparisons to transition metals indicate that the Mo-terminated Mo{sub 2}C(001) surface exhibits carbon reactivity similar to transition metals such as Ru and Ir, but is significantly more reactive towards oxygen.

Reactive sputter deposition

CERN Document Server

Mahieu, Stijn

2008-01-01

In this valuable work, all aspects of the reactive magnetron sputtering process, from the discharge up to the resulting thin film growth, are described in detail, allowing the reader to understand the complete process. Hence, this book gives necessary information for those who want to start with reactive magnetron sputtering, understand and investigate the technique, control their sputtering process and tune their existing process, obtaining the desired thin films.

Periodic transients linked to a variation in reactivity; Transitoires de periode lies a une variation de reactivite

Energy Technology Data Exchange (ETDEWEB)

Furet, J; Weil, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

We study here the influence of the transient, linked to a variation in reactivity, on the measurement of the period, this measurement being made from the logarithmic differential of the power and being defined by 1/T 1/p(dp/dt). We show that the adjustment of the thresholds of period safety is often incompatible with the velocities of liberation of reactivity. A compromise is then necessary between the speed of response of the periodimeter and the speed with which the reactivity is liberated. This makes it necessary to have rapid security devices for the power levels in the piles in which the speeds of liberation of the reactivity are high. (author) [French] On etudie ici l'influence du transitoire lie a une variation de la reactivite sur la mesure de la periode, cette mesure etant faite a partir de la derivee logarithmique de la puissance et etant definie par 1/T 1/p(dp/dt). On montre que le reglage des seuils de securite periode est souvent incompatible avec les vitesses de liberation de reactivite. Il y a alors un compromis a faire entre la vitesse de reponse du periodemetre et la vitesse de liberation de reactivite. Ceci impose de disposer de securites rapides sur les niveaux de puissance, dans les piles ou les vitesses de liberation de reactivite sont importantes. (auteur)

Boron-carbide-aluminum and boron-carbide-reactive metal cermets. [B/sub 4/C-Al

Science.gov (United States)

Halverson, D.C.; Pyzik, A.J.; Aksay, I.A.

1985-05-06

Hard, tough, lighweight boron-carbide-reactive metal composites, particularly boron-carbide-aluminum composites, are produced. These composites have compositions with a plurality of phases. A method is provided, including the steps of wetting and reacting the starting materials, by which the microstructures in the resulting composites can be controllably selected. Starting compositions, reaction temperatures, reaction times, and reaction atmospheres are parameters for controlling the process and resulting compositions. The ceramic phases are homogeneously distributed in the metal phases and adhesive forces at ceramic-metal interfaces are maximized. An initial consolidated step is used to achieve fully dense composites. Microstructures of boron-carbide-aluminum cermets have been produced with modules of rupture exceeding 110 ksi and fracture toughness exceeding 12 ksi..sqrt..in. These composites and methods can be used to form a variety of structural elements.

Reactive programming in eventsourcing systems

OpenAIRE

Kučinskas, Žilvinas

2017-01-01

Eventsourcing describes current state as series of events that occurred in a system. Events hold all information that is needed to recreate current state. This method allows to achieve high volume of transactions, and enables efficient replication. Whereas reactive programming lets implement reactive systems in declarative style, decomposing logic into smaller, easier to understand components. Thesis aims to create reactive programming program interface, incorporating both principles. Applyin...

Mood reactivity rather than cognitive reactivity is predictive of depressive relapse: a randomized study with 5.5-year follow-up

NARCIS (Netherlands)

van Rijsbergen, Gerard D.; Bockting, Claudi L. H.; Burger, Huibert; Spinhoven, Philip; Koeter, Maarten W. J.; Ruhé, Henricus G.; Hollon, Steven D.; Schene, Aart H.

2013-01-01

The current study examined whether cognitive reactivity, cognitive extremity reactivity, and mood reactivity following mood provocation predicted relapse in depression over 5.5 years. Additionally, this study was the 1st to examine whether changes in cognitive reactivity and mood reactivity

Processing of polymers using reactive solvents

NARCIS (Netherlands)

Lemstra, P.J.; Kurja, J.; Meijer, H.E.H.; Meijer, H.E.H.

1997-01-01

A review with many refs. on processing of polymers using reactive solvents including classification of synthetic polymers, guidelines for the selection of reactive solvents, basic aspects of processing, examples of intractable and tractable polymer/reactive solvent system

Prognostic Value of C-Reactive Protein, Leukocytes, and Vitamin D in Severe Chronic Obstructive Pulmonary Disease

DEFF Research Database (Denmark)

Moberg, Mia; Vestbo, Jørgen; Martinez, Gerd

2014-01-01

Inflammatory biomarkers predict mortality and hospitalisation in chronic obstructive pulmonary disease (COPD). Yet, it remains uncertain if biomarkers in addition to reflecting disease severity add new prognostic information on severe COPD. We investigated if leukocytes, C-reactive protein (CRP......), and vitamin D were independent predictors of mortality and hospitalisation after adjusting for disease severity with an integrative index, the i-BODE index. In total, 423 patients participating in a pulmonary rehabilitation programme, with a mean value of FEV1 of 38% of predicted, were included. Mean followup...... was 45 months. During the follow-up period, 149 deaths (35%) were observed and 330 patients (78.0%) had at least one acute hospitalisation; 244 patients (57.7%) had at least one hospitalisation due to an exacerbation of COPD. In the analysis (Cox proportional hazards model) fully adjusted for age, sex...

Definition of reactivity and its measurability

International Nuclear Information System (INIS)

Hu Dapu

1986-01-01

Reactivity is the fundamental and important physical quantity in the reactor physics. The different kinds of method for defining reactivity are represented, the difference between different definitions of reactivity is indicalted and the conditions under which they have nearly the same measurable value are discussed. It is demonstrated that when the static adjointed neutron density or the neutron importance is selected to be a weight function for generating kinetic parameters used in the neutron kinetic equations, the kinetic reactivity is approximately equal to the static reactivity. Due to the constraint of the normalization condition, the shape function must be so selected that the corresponding amplitude function is proportional to the fundamental mode of neutron density variating with time. Measured reactivity by the kinetic method may vary with the position of detector, owing to the different space distribution of the prompt neutrons density and the delayed neutrons density and the effect of the higher harmonics of the neutron density. Some corresponding correction must be made in order to obtain the real static reactivity

A new concept for spatially divided Deep Reactive Ion Etching with ALD-based passivation

International Nuclear Information System (INIS)

Roozeboom, F; Kniknie, B; Lankhorst, A M; Winands, G; Knaapen, R; Smets, M; Poodt, P; Dingemans, G; Keuning, W; Kessels, W M M

2012-01-01

Conventional Deep Reactive Ion Etching (DRIE) is a plasma etch process with alternating half-cycles of 1) Si-etching with SF 6 to form gaseous SiF x etch products, and 2) passivation with C 4 F 8 that polymerizes as a protecting fluorocarbon deposit on the sidewalls and bottom of the etched features. In this work we report on a novel alternative and disruptive technology concept of Spatially-divided Deep Reactive Ion Etching, S-DRIE, where the process is converted from the time-divided into the spatially divided regime. The spatial division can be accomplished by inert gas bearing 'curtains' of heights down to ∼20 μm. These curtains confine the reactive gases to individual (often linear) injection slots constructed in a gas injector head. By horizontally moving the substrate back and forth under the head one can realize the alternate exposures to the overall cycle. A second improvement in the spatially divided approach is the replacement of the CVD-based C 4 F 8 passivation steps by ALD-based oxide (e.g. SiO 2 ) deposition cycles. The method can have industrial potential in cost-effective creation of advanced 3D interconnects (TSVs), MEMS manufacturing and advanced patterning, e.g., in nanoscale transistor line edge roughness using Atomic Layer Etching.

Electrospinning of reactive mesogens

NARCIS (Netherlands)

Yao, J.; Picot, O.T.; Hughes-Brittain, N.F.; Bastiaansen, C.W.M.; Peijs, T.

2016-01-01

The reinforcement potential of reactive liquid crystals or reactive mesogens (RMs) in electrospun fibers was investigated through the blending of two types of RMs (RM257 and RM82) with two types of thermoplastics; polyamide 6 (PA6) and poly(methyl methacrylate) (PMMA). Polymer/RM blends were

Repatriation Adjustment: Literature Review

Directory of Open Access Journals (Sweden)

Gamze Arman

2009-12-01

Full Text Available Expatriation is a widely studied area of research in work and organizational psychology. After expatriates accomplish their missions in host countries, they return to their countries and this process is called repatriation. Adjustment constitutes a crucial part in repatriation research. In the present literature review, research about repatriation adjustment was reviewed with the aim of defining the whole picture in this phenomenon. Present research was classified on the basis of a theoretical model of repatriation adjustment. Basic frame consisted of antecedents, adjustment, outcomes as main variables and personal characteristics/coping strategies and organizational strategies as moderating variables.

One-step generation of continuous-variable quadripartite cluster states in a circuit QED system

Science.gov (United States)

Yang, Zhi-peng; Li, Zhen; Ma, Sheng-li; Li, Fu-li

2017-07-01

We propose a dissipative scheme for one-step generation of continuous-variable quadripartite cluster states in a circuit QED setup consisting of four superconducting coplanar waveguide resonators and a gap-tunable superconducting flux qubit. With external driving fields to adjust the desired qubit-resonator and resonator-resonator interactions, we show that continuous-variable quadripartite cluster states of the four resonators can be generated with the assistance of energy relaxation of the qubit. By comparison with the previous proposals, the distinct advantage of our scheme is that only one step of quantum operation is needed to realize the quantum state engineering. This makes our scheme simpler and more feasible in experiment. Our result may have useful application for implementing quantum computation in solid-state circuit QED systems.

A Reactive Balance Rating Method that Correlates with Kinematics after Trip-Like Perturbations on a Treadmill and Fall Risk Among Residents of Older Adult Congregate Housing.

Science.gov (United States)

Madigan, Michael L; Aviles, Jessica; Allin, Leigh J; Nussbaum, Maury A; Alexander, Neil B

2018-04-16

A growing number of studies are using modified treadmills to train reactive balance after trip-like perturbations that require multiple steps to recover balance. The goal of this study was thus to develop and validate a low-tech reactive balance rating method in the context of trip-like treadmill perturbations to facilitate the implementation of this training outside the research setting. Thirty-five residents of five senior congregate housing facilities participated in the study. Subjects completed a series of reactive balance tests on a modified treadmill from which the reactive balance rating was determined, along with a battery of standard clinical balance and mobility tests that predict fall risk. We investigated the strength of correlation between the reactive balance rating and reactive balance kinematics. We compared the strength of correlation between the reactive balance rating and clinical tests predictive of fall risk, with the strength of correlation between reactive balance kinematics and the same clinical tests. We also compared the reactive balance rating between subjects predicted to be at a high or low risk of falling. The reactive balance rating was correlated with reactive balance kinematics (Spearman's rho squared = .04 - .30), exhibited stronger correlations with clinical tests than most kinematic measures (Spearman's rho squared = .00 - .23), and was 42-60% lower among subjects predicted to be at a high risk for falling. The reactive balance rating method may provide a low-tech, valid measure of reactive balance kinematics, and an indicator of fall risk, after trip-like postural perturbations.

Self-triggered assistive stimulus training improves step initiation in persons with Parkinson’s disease

Directory of Open Access Journals (Sweden)

Creath Robert A

2013-01-01

Full Text Available Abstract Background Prior studies demonstrated that hesitation-prone persons with Parkinson’s disease (PDs acutely improve step initiation using a novel self-triggered stimulus that enhances lateral weight shift prior to step onset. PDs showed reduced anticipatory postural adjustment (APA durations, earlier step onsets, and faster 1st step speed immediately following stimulus exposure. Objective This study investigated the effects of long-term stimulus exposure. Methods Two groups of hesitation-prone subjects with Parkinson’s disease (PD participated in a 6-week step-initiation training program involving one of two stimulus conditions: 1 Drop. The stance-side support surface was lowered quickly (1.5 cm; 2 Vibration. A short vibration (100 ms was applied beneath the stance-side support surface. Stimuli were self-triggered by a 5% reduction in vertical force under the stance foot during the APA. Testing was at baseline, immediately post-training, and 6 weeks post-training. Measurements included timing and magnitude of ground reaction forces, and step speed and length. Results Both groups improved their APA force modulation after training. Contrary to previous results, neither group showed reduced APA durations or earlier step onset times. The vibration group showed 55% increase in step speed and a 39% increase in step length which were retained 6 weeks post-training. The drop group showed no stepping-performance improvements. Conclusions The acute sensitivity to the quickness-enhancing effects of stimulus exposure demonstrated in previous studies was supplanted by improved force modulation following prolonged stimulus exposure. The results suggest a potential approach to reduce the severity of start hesitation in PDs, but further study is needed to understand the relationship between short- and long-term effects of stimulus exposure.

Step-growth polymerizing systems of general type “AfiBgi” : calculating the radius of gyration and the g-curve using generating functions and recurrences

NARCIS (Netherlands)

Hillegers, L.T.M.E.; Slot, J.J.M.

2017-01-01

Step-growth polymerized systems of general type “AfiBgi” are considered. One or more of the monomer species carries at least three reactive groups and thus can act as a branching point in a polymeric molecule. An algorithmic method is presented to calculate the topology-averaged square radius of

Adatom Fe(III on the hematite surface: Observation of a key reactive surface species

Directory of Open Access Journals (Sweden)

Rosso Kevin M

2004-06-01

Full Text Available The reactivity of a mineral surface is determined by the variety and population of different types of surface sites (e.g., step, kink, adatom, and defect sites. The concept of "adsorbed nutrient" has been built into crystal growth theories, and many other studies of mineral surface reactivity appeal to ill-defined "active sites." Despite their theoretical importance, there has been little direct experimental or analytical investigation of the structure and properties of such species. Here, we use ex-situ and in-situ scanning tunneling microcopy (STM combined with calculated images based on a resonant tunneling model to show that observed nonperiodic protrusions and depressions on the hematite (001 surface can be explained as Fe in an adsorbed or adatom state occupying sites different from those that result from simple termination of the bulk mineral. The number of such sites varies with sample preparation history, consistent with their removal from the surface in low pH solutions.

The effects of zinc bath temperature on the coating growth behavior of reactive steel

Energy Technology Data Exchange (ETDEWEB)

Wang Jianhua, E-mail: super_wang111@hotmail.com [School of Mechanical Engineering, Xiangtan University, Xiangtan, 411105 (China); Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan, 411105 (China); Tu Hao; Peng Bicao; Wang Xinming; Yin, Fucheng [School of Mechanical Engineering, Xiangtan University, Xiangtan, 411105 (China); Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan, 411105 (China); Su Xuping, E-mail: xuping@xtu.edu.cn [School of Mechanical Engineering, Xiangtan University, Xiangtan, 411105 (China); Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan, 411105 (China)

2009-11-15

The purpose of this work is to identify the influence of zinc bath temperature on the morphology and the thickness of reactive steel (Fe-0.1 wt.%Si alloy) coatings. The Fe-0.1 wt.%Si samples were galvanized for 3 min at temperatures in the range of 450-530 deg. C in steps of 10 deg. C. The coatings were characterized by using scanning electron microscopy/energy dispersive X-rays analysis. It was found that the coating thickness reaches the maximum at 470 deg. C and the minimum at 500 deg. C, respectively. When the reactive steel is galvanized at temperatures in the range of 450-490 deg. C, the coatings have a loose {zeta} layer on the top of a compact {delta} layer. With the increase of the galvanizing temperature, the {zeta} layer becomes looser. When the temperature is at 500 deg. C, the {zeta} phase disappears. With the increase of temperature, the coatings change to be a diffuse-{Delta} layer ({delta}+ liquid zinc).

Surrogate model approach for improving the performance of reactive transport simulations

Science.gov (United States)

Jatnieks, Janis; De Lucia, Marco; Sips, Mike; Dransch, Doris

2016-04-01

(MARS) method provides the best trade-off between speed and accuracy. This proof-of-concept forms an essential step towards building an interactive visual analytics system to enable user-driven systematic creation of geochemical surrogate models. Such a system shall enable reactive transport simulations with unprecedented spatial and temporal detail to become possible. References: Kolditz, O., Görke, U.J., Shao, H. and Wang, W., 2012. Thermo-hydro-mechanical-chemical processes in porous media: benchmarks and examples (Vol. 86). Springer Science & Business Media.

Reactive Power from Distributed Energy

Energy Technology Data Exchange (ETDEWEB)

Kueck, John; Kirby, Brendan; Rizy, Tom; Li, Fangxing; Fall, Ndeye

2006-12-15

Distributed energy is an attractive option for solving reactive power and distribution system voltage problems because of its proximity to load. But the cost of retrofitting DE devices to absorb or produce reactive power needs to be reduced. There also needs to be a market mechanism in place for ISOs, RTOs, and transmission operators to procure reactive power from the customer side of the meter where DE usually resides. (author)

Reactive Power from Distributed Energy

International Nuclear Information System (INIS)

Kueck, John; Kirby, Brendan; Rizy, Tom; Li, Fangxing; Fall, Ndeye

2006-01-01

Distributed energy is an attractive option for solving reactive power and distribution system voltage problems because of its proximity to load. But the cost of retrofitting DE devices to absorb or produce reactive power needs to be reduced. There also needs to be a market mechanism in place for ISOs, RTOs, and transmission operators to procure reactive power from the customer side of the meter where DE usually resides. (author)

Engine combustion control via fuel reactivity stratification

Science.gov (United States)

Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

2013-12-31

A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

Marginal thermal-neutron peak fluxes in systems with modulation of reactivity

International Nuclear Information System (INIS)

Alekseev, N.I.; Stolypin, V.S.

1978-01-01

A possibility of obtaining high (including marginal) thermal neutron peak fluxes PHIsub(m) in a light water trap of a pulsed fast reactor with modulation of reactivity has been studied. The dependences of sub(m) on the subcriticality and supercriticality as well as on the supercritical state duration have been calculated on stepped variations of the reactivity. The calculations show that PHIsub(m) of about 7.3x10 18 neutron/cm 2 xs with the effective pulse duration of approximately 150 μc, pulse frequency of approximately 1 Hz and at fuel temperature of approximately 1300 deg C can be obtained with the reactor. The comparative calculations show that sub(m) is 1.5 times higher than that of a booster obtained using a ''meson plant'' (designs of the booster and the reactor are equivalent). The neutron background between pulses in the reactor is much lower than in the booster, and there is no need for a power injector in the reactor altogether. Meanwhile the maximum attainable PHIsub(m) for the booster and the reactor are the same and equal approximately 2x10 19 neutron/cm 2 xs

Two-Step Optimization for Spatial Accessibility Improvement: A Case Study of Health Care Planning in Rural China

Directory of Open Access Journals (Sweden)

Jing Luo

2017-01-01

Full Text Available A recent advancement in location-allocation modeling formulates a two-step approach to a new problem of minimizing disparity of spatial accessibility. Our field work in a health care planning project in a rural county in China indicated that residents valued distance or travel time from the nearest hospital foremost and then considered quality of care including less waiting time as a secondary desirability. Based on the case study, this paper further clarifies the sequential decision-making approach, termed “two-step optimization for spatial accessibility improvement (2SO4SAI.” The first step is to find the best locations to site new facilities by emphasizing accessibility as proximity to the nearest facilities with several alternative objectives under consideration. The second step adjusts the capacities of facilities for minimal inequality in accessibility, where the measure of accessibility accounts for the match ratio of supply and demand and complex spatial interaction between them. The case study illustrates how the two-step optimization method improves both aspects of spatial accessibility for health care access in rural China.

Predictive value of reactive hyperemia for cardiovascular events in patients with peripheral arterial disease undergoing vascular surgery.

Science.gov (United States)

Huang, Alex L; Silver, Annemarie E; Shvenke, Elena; Schopfer, David W; Jahangir, Eiman; Titas, Megan A; Shpilman, Alex; Menzoian, James O; Watkins, Michael T; Raffetto, Joseph D; Gibbons, Gary; Woodson, Jonathan; Shaw, Palma M; Dhadly, Mandeep; Eberhardt, Robert T; Keaney, John F; Gokce, Noyan; Vita, Joseph A

2007-10-01

Reactive hyperemia is the compensatory increase in blood flow that occurs after a period of tissue ischemia, and this response is blunted in patients with cardiovascular risk factors. The predictive value of reactive hyperemia for cardiovascular events in patients with atherosclerosis and the relative importance of reactive hyperemia compared with other measures of vascular function have not been previously studied. We prospectively measured reactive hyperemia and brachial artery flow-mediated dilation by ultrasound in 267 patients with peripheral arterial disease referred for vascular surgery (age 66+/-11 years, 26% female). Median follow-up was 309 days (range 1 to 730 days). Fifty patients (19%) had an event, including cardiac death (15), myocardial infarction (18), unstable angina (8), congestive heart failure (6), and nonhemorrhagic stroke (3). Patients with an event were older and had lower hyperemic flow velocity (75+/-39 versus 95+/-50 cm/s, P=0.009). Patients with an event also had lower flow-mediated dilation (4.5+/-3.0 versus 6.9+/-4.6%, P<0.001), and when these 2 measures of vascular function were included in the same Cox proportional hazards model, lower hyperemic flow (OR 2.7, 95% CI 1.2 to 5.9, P=0.018) and lower flow-mediated dilation (OR 4.2, 95% CI: 1.8 to 9.8, P=0.001) both predicted cardiovascular events while adjusting for other risk factors. Thus, lower reactive hyperemia is associated with increased cardiovascular risk in patients with peripheral arterial disease. Furthermore, flow-mediated dilation and reactive hyperemia incrementally relate to cardiovascular risk, although impaired flow-mediated dilation was the stronger predictor in this population. These findings further support the clinical relevance of vascular function measured in the microvasculature and conduit arteries in the upper extremity.

Microwave-assisted one-step patterning of aqueous colloidal silver.

Science.gov (United States)

Yang, G; Zhou, Y W; Guo, Z R; Wan, Y; Ding, Q; Bai, T T; Wang, C L; Gu, N

2012-07-05

A new approach of utilizing microwave to pattern gradient concentric silver nanoparticle ring structures has been presented. The width and height of a single ring and the space between adjacent rings can be adjusted by changing the silver colloidal concentration and the microwave output power. By simply enhancing the ambient vapour pressure to the saturated value during microwave-assisted evaporation, sub-100 nm rings can be deposited in between adjacent micro-rings over a distance of millimetres. Combined with microwave sintering, this approach can also create conductive silver tracks in a single step, showing huge potential in fabricating micro- and nano-electronic devices in an ultra-fast and cost-effective fashion.

Biodecolorization and biodegradation of Reactive Blue by ...

African Journals Online (AJOL)

SERVER

2007-06-18

Jun 18, 2007 ... Aspergillus sp. effectively decolorized Reactive Blue and other structurally different synthetic dyes. Agitation was found to be an important ... Few chemically different dyes such as Reactive Black (75%), Reactive Yellow (70%),. Reactive Red (33%) and ..... Degradation of azo dyes by the lignin degrading ...

Experimental estimation of moderator temperature coefficient of reactivity of the IPEN/MB-01 research reactor

Energy Technology Data Exchange (ETDEWEB)

Silva, Rubens C. da; Bitelli, Ulysses D.; Mura, Luiz Ernesto C., E-mail: rubensrcs@usp.br, E-mail: ubitelli@ipen.br, E-mail: credidiomura@gmail.com [Universidade de Sao Paulo (PNV/POLI/USP), SP (Brazil). Arquitetura Naval e Departamento de Engenharia Oceanica; Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2017-07-01

The aim of this article is to present the procedure for the experimental estimation of the Moderator Temperature Coefficient of Reactivity of the IPEN/MB-01 Research Reactor, a parameter that has an important role in the physics and the control operations of any reactor facility. At the experiment, the IPEN/MB-01 reactor went critical at the power of 1W (1% of its total power), and whose core configuration was 28 x 26 rectangular array of UO{sub 2} fuel rods, inside a light water (moderator) tank. In addition, there was a heavy water (D{sub 2}O) reflector installed in the West side of the core to obtain an adequate neutron reflection along the experiment. The moderator temperature was increased in steps of 4 °C, and the measurement of the mean moderator temperature was acquired using twelve calibrated thermocouples, placed around the reactor core. As a result, the mean value of -4.81 pcm/°C was obtained for such coefficient. The curves of ρ(T) (Reactivity x Temperature) and α{sup M}{sub T}(T)(Moderator Temperature Coefficient of Reactivity x Temperature) were developed using data from an experimental measurement of the integral reactivity curves through the Stable Period and Inverse Kinetics Methods, that was carried out at the reactor with the same core configuration. Such curves were compared and showed a very similar behavior between them. (author)

Reactive Programming in Standard ML

OpenAIRE

Pucella, Riccardo

2004-01-01

Reactive systems are systems that maintain an ongoing interaction with their environment, activated by receiving input events from the environment and producing output events in response. Modern programming languages designed to program such systems use a paradigm based on the notions of instants and activations. We describe a library for Standard ML that provides basic primitives for programming reactive systems. The library is a low-level system upon which more sophisticated reactive behavi...

Significance of isolated reactive treponemal chemiluminescence immunoassay results.

Science.gov (United States)

Hunter, Michael G; Robertson, Peter W; Post, Jeffrey J

2013-05-01

Isolated reactive serum treponemal chemiluminescence immunoassay (CIA) specimens cause clinical uncertainty. Sera were screened by CIA, and reactive samples underwent reflex testing with rapid plasma reagin (RPR), Treponema pallidum particle agglutination (TPPA), and fluorescent treponemal antibody absorption (FTA Abs) assays. Samples reactive only on the CIA were deemed "isolated" reactive CIA samples. We undertook detailed review of a subset of subjects with isolated reactive CIA specimens. Of 28 261 specimens, 1171 (4.1%) were reactive on CIA, of which 133 (11.3%) had isolated CIA reactivity. Most subjects (66 of 82 [80.5%]) with isolated reactive CIA specimens were from high-prevalence populations. We found evidence of CIA, TPPA, and FTA Abs seroreversion. The median chemiluminescent signal-to-cutoff ratio was similar for isolated reactive CIA sera and sera that were reactive on either FTA Abs or TPPA assays (2.19 vs 2.32; P = .15) but lower than for sera reactive on both FTA Abs and TPPA assays (12.37; P < .001) or for sera reactive on RPR assays (25.53; P < .001). A total of 11 of 20 patients (55%) with an isolated reactive CIA specimen who underwent medical record review had previous or subsequent evidence of syphilis infection. Isolated reactive CIA specimens may represent true T. pallidum infection and may be found after seroreversion of traditional treponemal assays.

Discrete pre-processing step effects in registration-based pipelines, a preliminary volumetric study on T1-weighted images.

Science.gov (United States)

Muncy, Nathan M; Hedges-Muncy, Ariana M; Kirwan, C Brock

2017-01-01

Pre-processing MRI scans prior to performing volumetric analyses is common practice in MRI studies. As pre-processing steps adjust the voxel intensities, the space in which the scan exists, and the amount of data in the scan, it is possible that the steps have an effect on the volumetric output. To date, studies have compared between and not within pipelines, and so the impact of each step is unknown. This study aims to quantify the effects of pre-processing steps on volumetric measures in T1-weighted scans within a single pipeline. It was our hypothesis that pre-processing steps would significantly impact ROI volume estimations. One hundred fifteen participants from the OASIS dataset were used, where each participant contributed three scans. All scans were then pre-processed using a step-wise pipeline. Bilateral hippocampus, putamen, and middle temporal gyrus volume estimations were assessed following each successive step, and all data were processed by the same pipeline 5 times. Repeated-measures analyses tested for a main effects of pipeline step, scan-rescan (for MRI scanner consistency) and repeated pipeline runs (for algorithmic consistency). A main effect of pipeline step was detected, and interestingly an interaction between pipeline step and ROI exists. No effect for either scan-rescan or repeated pipeline run was detected. We then supply a correction for noise in the data resulting from pre-processing.

Covalent modification of cytochrome c by reactive metabolites of furan.

Science.gov (United States)

Phillips, Martin B; Sullivan, Mathilde M; Villalta, Peter W; Peterson, Lisa A

2014-01-21

Metabolism of the hepatotoxicant furan leads to protein adduct formation in the target organ. The initial bioactivation step involves cytochrome P450-catalyzed oxidation of furan, generating cis-2-butene-1,4-dial (BDA). BDA reacts with lysine to form pyrrolin-2-one adducts. Metabolic studies indicate that BDA also reacts with glutathione (GSH) to generate 2-(S-glutathionyl)butanedial (GSH-BDA), which then reacts with lysine to form GSH-BDA-lysine cross-links. To explore the relative reactivity of these two reactive intermediates, cytochrome c was reacted with BDA in the presence and absence of GSH. As judged by MALDI-TOF mass spectrometry, BDA reacts extensively with cytochrome c to form adducts that add 66 Da to the protein, consistent with the formation of pyrrolinone adducts. Addition of GSH to the reaction mixture reduced the overall extent of adduct formation. The mass of the adducted protein was shifted by 355 Da as expected for GSH-BDA-protein cross-link formation. LC-MS/MS analysis of the tryptic digests of the alkylated protein indicated that the majority of adducts occurred on lysine residues, with BDA reacting less selectively than GSH-BDA. Both types of adducts may contribute to the toxic effects of furan.

Synthesis of Aluminum Triacrylate as Reactive Filler in EPDM Reinforcement

Directory of Open Access Journals (Sweden)

Akram Shokrzadeh

2013-01-01

Full Text Available The organo-metal salt of aluminum triacrylate (ALTA with a general formula of (CH2=CHCOO3Al was  synthesized  as  a  reactive  fller  for  elastomers through a two-step synthetic procedure. Fourier transform-infrared spectroscopy (FTIR, DSC and DTA were employed for ALTA analysis and to study its cure characteristics. In this research, two composites based on ethylene propylene diene monomer rubber (EPDM with two types of reactive fllers of  modifed organoclay and ALTA were prepared by a laboratory two-roll mill. The types and different ratios of organoclay and ALTA on curing characteristics, mechanical properties such as tensile properties, hardness, and abrasion resistance were studied. The increase in fller content of both composites  led  to  the  incremental  increase  in  tensile strength, modulus, hardness, elongation-at-break and also the incremental increase in abrasion resistance of both composites. The improvement in reinforcing properties of ALTA in comparison with nanoclay is attributed to homopolymerization and graft copolymerization of ALTA at the same time during curing of the EPDM composites by peroxide. Making such additives may be taken as an effective action to achieve more durable and cheaper way to reinforce elastomers.

Predicting Reactive Transport Dynamics in Carbonates using Initial Pore Structure

Science.gov (United States)

Menke, H. P.; Nunes, J. P. P.; Blunt, M. J.

2017-12-01

Understanding rock-fluid interaction at the pore-scale is imperative for accurate predictive modelling of carbon storage permanence. However, coupled reactive transport models are computationally expensive, requiring either a sacrifice of resolution or high performance computing to solve relatively simple geometries. Many recent studies indicate that initial pore structure many be the dominant mechanism in determining the dissolution regime. Here we investigate how well the initial pore structure is predictive of distribution and amount of dissolution during reactive flow using particle tracking on the initial image. Two samples of carbonate rock with varying initial pore space heterogeneity were reacted with reservoir condition CO2-saturated brine and scanned dynamically during reactive flow at a 4-μm resolution between 4 and 40 times using 4D X-ray micro-tomography over the course of 1.5 hours using μ-CT. Flow was modelled on the initial binarized image using a Navier-Stokes solver. Particle tracking was then run on the velocity fields, the streamlines were traced, and the streamline density was calculated both on a voxel-by-voxel and a channel-by-channel basis. The density of streamlines was then compared to the amount of dissolution in subsequent time steps during reaction. It was found that for the flow and transport regimes studied, the streamline density distribution in the initial image accurately predicted the dominant pathways of dissolution and gave good indicators of the type of dissolution regime that would later develop. This work suggests that the eventual reaction-induced changes in pore structure are deterministic rather than stochastic and can be predicted with high resolution imaging of unreacted rock.

Multilevel hybrid split-step implicit tau-leap

KAUST Repository

Ben Hammouda, Chiheb

2016-06-17

In biochemically reactive systems with small copy numbers of one or more reactant molecules, the dynamics is dominated by stochastic effects. To approximate those systems, discrete state-space and stochastic simulation approaches have been shown to be more relevant than continuous state-space and deterministic ones. In systems characterized by having simultaneously fast and slow timescales, existing discrete space-state stochastic path simulation methods, such as the stochastic simulation algorithm (SSA) and the explicit tau-leap (explicit-TL) method, can be very slow. Implicit approximations have been developed to improve numerical stability and provide efficient simulation algorithms for those systems. Here, we propose an efficient Multilevel Monte Carlo (MLMC) method in the spirit of the work by Anderson and Higham (SIAM Multiscal Model. Simul. 10(1), 2012). This method uses split-step implicit tau-leap (SSI-TL) at levels where the explicit-TL method is not applicable due to numerical stability issues. We present numerical examples that illustrate the performance of the proposed method. © 2016 Springer Science+Business Media New York

Event-Based Modularization of Reactive Systems

NARCIS (Netherlands)

Malakuti Khah Olun Abadi, Somayeh; Aksit, Mehmet

2014-01-01

There is a large number of complex software systems that have reactive behavior. As for any other software system, reactive systems are subject to evolution demands. This paper defines a set requirements that must be fulfilled so that reuse of reactive software systems can be increased. Detailed

Single-Run Single-Mask Inductively-Coupled-Plasma Reactive-Ion-Etching Process for Fabricating Suspended High-Aspect-Ratio Microstructures

Science.gov (United States)

Yang, Yao-Joe; Kuo, Wen-Cheng; Fan, Kuang-Chao

2006-01-01

In this work, we present a single-run single-mask (SRM) process for fabricating suspended high-aspect-ratio structures on standard silicon wafers using an inductively coupled plasma-reactive ion etching (ICP-RIE) etcher. This process eliminates extra fabrication steps which are required for structure release after trench etching. Released microstructures with 120 μm thickness are obtained by this process. The corresponding maximum aspect ratio of the trench is 28. The SRM process is an extended version of the standard process proposed by BOSCH GmbH (BOSCH process). The first step of the SRM process is a standard BOSCH process for trench etching, then a polymer layer is deposited on trench sidewalls as a protective layer for the subsequent structure-releasing step. The structure is released by dry isotropic etching after the polymer layer on the trench floor is removed. All the steps can be integrated into a single-run ICP process. Also, only one mask is required. Therefore, the process complexity and fabrication cost can be effectively reduced. Discussions on each SRM step and considerations for avoiding undesired etching of the silicon structures during the release process are also presented.

Phosphonic acids aid composition adjustment in the synthesis of Cu{sub 2+x}Zn{sub 1−x}SnSe{sub 4−y} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Ibáñez, Maria; Berestok, Taisiia; Dobrozhan, Oleksandr [Catalonia Institute for Energy Research (IREC) (Spain); LaLonde, Aaron [California Institute of Technology, Materials Science (United States); Izquierdo-Roca, Victor; Shavel, Alexey; Pérez-Rodríguez, Alejandro [Catalonia Institute for Energy Research (IREC) (Spain); Snyder, G. Jeffrey [California Institute of Technology, Materials Science (United States); Cabot, Andreu, E-mail: acabot@irec.cat [Catalonia Institute for Energy Research (IREC) (Spain)

2016-08-15

The functional properties of quaternary I{sub 2}–II–IV–VI{sub 4} nanomaterials, with potential interest in various technological fields, are highly sensitive to compositional variations, which is a challenging parameter to adjust. Here we demonstrate the presence of phosphonic acids to aid controlling the reactivity of the II element monomer to be incorporated in quaternary Cu{sub 2}ZnSnSe{sub 4} nanoparticles and thus to provide a more reliable way to adjust the final nanoparticle metal ratios. Furthermore, we demonstrate the composition control in such multivalence nanoparticles to allow modifying charge carrier concentrations in nanomaterials produced from the assembly of these building blocks.

Reactive Desorption of CO Hydrogenation Products under Cold Pre-stellar Core Conditions

Science.gov (United States)

Chuang, K.-J.; Fedoseev, G.; Qasim, D.; Ioppolo, S.; van Dishoeck, E. F.; Linnartz, H.

2018-02-01

The astronomical gas-phase detection of simple species and small organic molecules in cold pre-stellar cores, with abundances as high as ∼10‑8–10‑9 n H, contradicts the generally accepted idea that at 10 K, such species should be fully frozen out on grain surfaces. A physical or chemical mechanism that results in a net transfer from solid-state species into the gas phase offers a possible explanation. Reactive desorption, i.e., desorption following the exothermic formation of a species, is one of the options that has been proposed. In astronomical models, the fraction of molecules desorbed through this process is handled as a free parameter, as experimental studies quantifying the impact of exothermicity on desorption efficiencies are largely lacking. In this work, we present a detailed laboratory study with the goal of deriving an upper limit for the reactive desorption efficiency of species involved in the CO–H2CO–CH3OH solid-state hydrogenation reaction chain. The limit for the overall reactive desorption fraction is derived by precisely investigating the solid-state elemental carbon budget, using reflection absorption infrared spectroscopy and the calibrated solid-state band-strength values for CO, H2CO and CH3OH. We find that for temperatures in the range of 10 to 14 K, an upper limit of 0.24 ± 0.02 for the overall elemental carbon loss upon CO conversion into CH3OH. This corresponds with an effective reaction desorption fraction of ≤0.07 per hydrogenation step, or ≤0.02 per H-atom induced reaction, assuming that H-atom addition and abstraction reactions equally contribute to the overall reactive desorption fraction along the hydrogenation sequence. The astronomical relevance of this finding is discussed.

Growth of ZnO nanowires on polypropylene membrane surface—Characterization and reactivity

Energy Technology Data Exchange (ETDEWEB)

Bojarska, Marta, E-mail: m.bojarska@ichip.pw.edu.pl [Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw (Poland); Lehrstuhl für Technische Chemie II, Universität Duisburg-Essen, Essen 45117 (Germany); Nowak, Bartosz, E-mail: novakbartosz@gmail.com [Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw (Poland); Skowroński, Jarosław, E-mail: jaroslaw.skowronski@itee.radom.pl [Institute for Sustainable Technologies—National Research Institute, Pułaskiego 6/10, 26-600 Radom (Poland); Piątkiewicz, Wojciech, E-mail: w.piatkiewicz@polymemtech.com [Institute for Sustainable Technologies—National Research Institute, Pułaskiego 6/10, 26-600 Radom (Poland); PolymemTech Sp. z o.o., al. Niepodległości 118/90, 02-577 Warsaw (Poland); Gradoń, Leon, E-mail: l.gradon@ichip.pw.edu.pl [Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw (Poland)

2017-01-01

Highlights: • ZnO nanowires were grown on a polypropylene microfiltration capillary membrane. • Plasma treatment was used for membrane activation and hydrophilization. • The photocatalytic/antibacterial properties were studied upon light irradiation. • PP/ZnO nanowires membrane show good photocatalytic and antibacterial activity. • We report a new method for obtaining reactive membranes with ZnO nanowires. - Abstract: Need for a new membrane is clearly visible in recent studies, mostly due to the fouling phenomenon. Authors, focused on problem of biofouling caused by microorganisms that are present in water environment. An attempt to form a new membrane with zinc oxide (ZnO) nanowires was made; where plasma treatment was used as a first step of modification followed by chemical bath deposition. Such membrane will exhibit additional reactive properties. ZnO, because of its antibacterial and photocatalytic properties, is more and more often used in commercial applications. The authors used SEM imaging, measurement of the contact angle, XRD and the FT–IR analysis for membrane characterization. Amount of ZnO deposited on membrane surface was also investigated by dithizone method. Photocatalytic properties of such membranes were examined through methylene blue and humic acid degradation in laboratory scale modules with LEDs as either: wide range white or UV light source. Antibacterial and antifouling properties of polypropylene membranes modified with ZnO nanowires were examined through a series of tests involving microorganisms: model gram-positive and −negative bacteria. The obtained results showed that it is possible to modify the membrane surface in such a way, that additional reactive properties will be given. Thus, not only did the membrane become a physical barrier, but also turned out to be a reactive one.

The Value of Step-by-Step Risk Assessment for Unmanned Aircraft

DEFF Research Database (Denmark)

La Cour-Harbo, Anders

2018-01-01

The new European legislation expected in 2018 or 2019 will introduce a step-by-step process for conducting risk assessments for unmanned aircraft flight operations. This is a relatively simple approach to a very complex challenge. This work compares this step-by-step process to high fidelity risk...... modeling, and shows that at least for a series of example flight missions there is reasonable agreement between the two very different methods....

Quantum Control of Graphene Plasmon Excitation and Propagation at Heaviside Potential Steps.

Science.gov (United States)

Wang, Dongli; Fan, Xiaodong; Li, Xiaoguang; Dai, Siyuan; Wei, Laiming; Qin, Wei; Wu, Fei; Zhang, Huayang; Qi, Zeming; Zeng, Changgan; Zhang, Zhenyu; Hou, Jianguo

2018-02-14

Quantum mechanical effects of single particles can affect the collective plasmon behaviors substantially. In this work, the quantum control of plasmon excitation and propagation in graphene is demonstrated by adopting the variable quantum transmission of carriers at Heaviside potential steps as a tuning knob. First, the plasmon reflection is revealed to be tunable within a broad range by varying the ratio γ between the carrier energy and potential height, which originates from the quantum mechanical effect of carrier propagation at potential steps. Moreover, the plasmon excitation by free-space photos can be regulated from fully suppressed to fully launched in graphene potential wells also through adjusting γ, which defines the degrees of the carrier confinement in the potential wells. These discovered quantum plasmon effects offer a unified quantum-mechanical solution toward ultimate control of both plasmon launching and propagating, which are indispensable processes in building plasmon circuitry.

Haplotype of platelet receptor P2RY12 gene is associated with residual clopidogrel on-treatment platelet reactivity.

Science.gov (United States)

Nie, Xiao-Yan; Li, Jun-Lei; Zhang, Yong; Xu, Yang; Yang, Xue-Li; Fu, Yu; Liang, Guang-Kai; Lu, Yun; Liu, Jian; Shi, Lu-Wen

To investigate a possible association between common variations of the P2RY12 and the residual clopidogrel on-treatment platelet reactivity after adjusting for the influence of CYP2C19 tested by thromboelastography (TEG). One hundred and eighty patients with acute coronary syndrome (ACS) treated with clopidogrel and aspirin were included and platelet function was assessed by TEG. Five selected P2RY12 single nucleotide polymorphisms (SNPs; rs6798347, rs6787801, rs6801273, rs6785930, and rs2046934), which cover the common variations in the P2RY12 gene and its regulatory regions, and three CYP2C19 SNPs ( * 2, * 3, * 17) were genotyped and possible haplotypes were analyzed. The high on-treatment platelet reactivity (HTPR) prevalence defined by a platelet inhibition rate <30% by TEG in adenosine diphosphate (ADP)-channel was 69 (38.33%). Six common haplotypes were inferred from four of the selected P2RY12 SNPs (denoted H 0 to H 5 ) according to the linkage disequilibrium R square (except for rs2046934). Haplotype H 1 showed a significantly lower incidence of HTPR than the reference haplotype (H 0 ) in the total study population while haplotypes H 1 and H 2 showed significantly lower incidences of HTPR than H 0 in the nonsmoker subgroup after adjusting for CYP2C19 effects and demographic characteristics. rs2046934 (T744C) did not show any significant association with HTPR. The combination of common P2RY12 variations including regulatory regions rather than rs2046934 (T744C) that related to pharmacodynamics of clopidogrel in patients with ACS was independently associated with residual on-clopidogrel platelet reactivity. This is apart from the established association of the CYP2C19. This association seemed more important in the subgroup defined by smoking.

Simulations geometric structures of the stepped profile bearing surface of the piston

Directory of Open Access Journals (Sweden)

Wroblewski Emil

2017-01-01

Full Text Available The main node piston-pin-piston rings are most responsible for the formation of mechanical losses. It is advisable to reduce friction losses in the piston-cylinder group lead to an increase in the overall efficiency of the engine and thus reduce the fuel consumption. The method to reduce the area covered by the oil film is a modification of the bearing surface of the piston by adjusting the profile. In this paper the results of simulation for the stepped microgeometry piston bearing surface are presented.

Tunable reactivity of supported single metal atoms by impurity engineering of the MgO(001) support.

Science.gov (United States)

Pašti, Igor A; Johansson, Börje; Skorodumova, Natalia V

2018-02-28

Development of novel materials may often require a rational use of high price components, like noble metals, in combination with the possibility to tune their properties in a desirable way. Here we present a theoretical DFT study of Au and Pd single atoms supported by doped MgO(001). By introducing B, C and N impurities into the MgO(001) surface, the interaction between the surface and the supported metal adatoms can be adjusted. Impurity atoms act as strong binding sites for Au and Pd adatoms and can help to produce highly dispersed metal particles. The reactivity of metal atoms supported by doped MgO(001), as probed by CO, is altered compared to their counterparts on pristine MgO(001). We find that Pd atoms on doped MgO(001) are less reactive than on perfect MgO(001). In contrast, Au adatoms bind CO much more strongly when placed on doped MgO(001). In the case of Au on N-doped MgO(001) we find that charge redistribution between the metal atom and impurity takes place even when not in direct contact, which enhances the interaction of Au with CO. The presented results suggest possible ways for optimizing the reactivity of oxide supported metal catalysts through impurity engineering.

Spring 5 & reactive streams

CERN Multimedia

CERN. Geneva; Clozel, Brian

2017-01-01

Spring is a framework widely used by the world-wide Java community, and it is also extensively used at CERN. The accelerator control system is constituted of 10 million lines of Java code, spread across more than 1000 projects (jars) developed by 160 software engineers. Around half of this (all server-side Java code) is based on the Spring framework. Warning: the speakers will assume that people attending the seminar are familiar with Java and Spring’s basic concepts. Spring 5.0 and Spring Boot 2.0 updates (45 min) This talk will cover the big ticket items in the 5.0 release of Spring (including Kotlin support, @Nullable and JDK9) and provide an update on Spring Boot 2.0, which is scheduled for the end of the year. Reactive Spring (1h) Spring Framework 5.0 has been released - and it now supports reactive applications in the Spring ecosystem. During this presentation, we'll talk about the reactive foundations of Spring Framework with the Reactor project and the reactive streams specification. We'll al...

Making real-time reactive systems reliable

Science.gov (United States)

Marzullo, Keith; Wood, Mark

1990-01-01

A reactive system is characterized by a control program that interacts with an environment (or controlled program). The control program monitors the environment and reacts to significant events by sending commands to the environment. This structure is quite general. Not only are most embedded real time systems reactive systems, but so are monitoring and debugging systems and distributed application management systems. Since reactive systems are usually long running and may control physical equipment, fault tolerance is vital. The research tries to understand the principal issues of fault tolerance in real time reactive systems and to build tools that allow a programmer to design reliable, real time reactive systems. In order to make real time reactive systems reliable, several issues must be addressed: (1) How can a control program be built to tolerate failures of sensors and actuators. To achieve this, a methodology was developed for transforming a control program that references physical value into one that tolerates sensors that can fail and can return inaccurate values; (2) How can the real time reactive system be built to tolerate failures of the control program. Towards this goal, whether the techniques presented can be extended to real time reactive systems is investigated; and (3) How can the environment be specified in a way that is useful for writing a control program. Towards this goal, whether a system with real time constraints can be expressed as an equivalent system without such constraints is also investigated.

Cross-reactivity of human nickel-reactive T-lymphocyte clones with copper and palladium

NARCIS (Netherlands)

Pistoor, F. H.; Kapsenberg, M. L.; Bos, J. D.; Meinardi, M. M.; von Blomberg, M. E.; Scheper, R. J.

1995-01-01

Twenty Ni-reactive T-lymphocyte clones were obtained from eight different donors and analyzed for their ability to cross-react with other metals. All Ni-reactive T-lymphocyte clones were CD4+CD8- and recognized Ni in association with either HLA-DR or -DQ molecules. Based on the periodic table of the

KfK analysis of the SUPER-PHENIX-1 control rod experiments. Pt. 1

International Nuclear Information System (INIS)

Giese, H.

1991-03-01

As proposed by the SPX-1 analysis task force, MSM (modified source multiplication) correction factors have been produced for a series of control rod configurations established in the first critical core C1D with minimum fissile loading and in the fully loaded core CMP. The report gives a complete description of the method used at KfK to produce these correction factors and summarises the evaluated experimental results obtained. The KfK method is characterized by a 'two-step-adjustment': A basic reactivity scale adjustment and a subsequent rod worth adjustment. The first adjustment was achieved by 'tuning' either the axialbuckling in the leakage term D B 2 or the average number of neutrons per fission in the production term so that the excess reactivity of the so-called 'Follower-core' with all control rods fully raised was properly reproduced. As this excess reactivity could not be directly determined by an experiment, it had to be assessed from the shut-down worth of the main control system in combination with measured fractions of the S-curve of this system. In the second adjustment, the absorber cross sections were tuned to reproduce experimental rod worths. While for the analysis of the C1D experiments, MSM correction factor calculations were performed in 2D centre-plane geometry only, the analysis of the CMP measurements employed both 2D and 3D calculations. (orig./HP)

Step-by-Step Visual Manuals: Design and Development

Science.gov (United States)

Urata, Toshiyuki

2004-01-01

The types of handouts and manuals that are used in technology training vary. Some describe procedures in a narrative way without graphics; some employ step-by-step instructions with screen captures. According to Thirlway (1994), a training manual should be like a tutor that permits a student to learn at his own pace and gives him confidence for…

Comparison of Reactive and Non-Reactive Spark Plasma Sintering Routes for the Fabrication of Monolithic and Composite Ultra High Temperature Ceramics (UHTC Materials

Directory of Open Access Journals (Sweden)

Roberto Orrù

2013-04-01

Full Text Available A wider utilization of ultra high temperature ceramics (UHTC materials strongly depends on the availability of efficient techniques for their fabrication as dense bodies. Based on recent results reported in the literature, it is possible to state that Spark Plasma Sintering (SPS technology offers a useful contribution in this direction. Along these lines, the use of two different SPS-based processing routes for the preparation of massive UHTCs is examined in this work. One method, the so-called reactive SPS (R-SPS, consists of the synthesis and densification of the material in a single step. Alternatively, the ceramic powders are first synthesized by Self-propagating High-temperature Synthesis (SHS and then sintered by SPS. The obtained results evidenced that R-SPS method is preferable for the preparation of dense monolithic products, while the sintering of SHS powders requires relatively milder conditions when considering binary composites. The different kinetic mechanisms involved during R-SPS of the monolithic and composite systems, i.e., combustion-like or gradual solid-diffusion, respectively, provides a possible explanation. An important role is also played by the SHS process, particularly for the preparation of composite powders, since stronger interfaces are established between the ceramic constituents formed in situ, thus favoring diffusion processes during the subsequent SPS step.

Mood reactivity rather than cognitive reactivity is predictive of depressive relapse : a randomized study with 5.5-year follow-up

NARCIS (Netherlands)

van Rijsbergen, Gerard D; Bockting, Claudi L H; Burger, Huibert; Spinhoven, Philip; Koeter, Maarten W J; Ruhe, Eric; Hollon, Steven D; Schene, Aart H

OBJECTIVE: The current study examined whether cognitive reactivity, cognitive extremity reactivity, and mood reactivity following mood provocation predicted relapse in depression over 5.5 years. Additionally, this study was the 1st to examine whether changes in cognitive reactivity and mood

Pain-related stress in the Neonatal Intensive Care Unit and salivary cortisol reactivity to socio-emotional stress in 3-month-old very preterm infants.

Science.gov (United States)

Provenzi, Livio; Giusti, Lorenzo; Fumagalli, Monica; Tasca, Hilarj; Ciceri, Francesca; Menozzi, Giorgia; Mosca, Fabio; Morandi, Francesco; Borgatti, Renato; Montirosso, Rosario

2016-10-01

Very preterm (VPT) infants are hospitalized in the Neonatal Intensive Care Unit (NICU) and exposed to varying levels of skin-breaking procedures (pain-related stress), even in absence of severe clinical conditions. Repeated and prolonged pain exposure may alter hypothalamic-pituitary-adrenal (HPA) axis reactivity in VPT infants. During the post-discharge period, altered HPA axis reactivity has been documented in response to non-social stressors, using salivary cortisol as a biomarker. However, little is known about the effects of NICU pain-related stress on subsequent HPA axis reactivity to socio-emotional stress in infants. We examined the relationship between pain-related stress in NICU and HPA axis reactivity (i.e., salivary cortisol reactivity) to an age-appropriate socio-emotional condition in 37 healthy VPT infants compared to 53 full-term (FT) controls. The number of skin-breaking procedures was obtained across NICU stay for VPT infants. At 3 months (corrected age for prematurity), all infants participated in the maternal Face-to-Face Still-Face (FFSF) procedure, in order to assess HPA axis reactivity to socio-emotional stress (i.e., maternal unresponsiveness). VPT infants exhibited a blunted salivary cortisol reactivity, which was associated with the amount of skin-breaking procedures during NICU: greater pain-related stress predicted lower salivary cortisol reactivity, adjusting for neonatal confounders. These findings further advance our knowledge of how early exposure to pain-related stress in NICU contributes to the programming of an altered HPA axis reactivity to socio-emotional stress in 3-month-old VPT infants, even in the absence of major perinatal complications. Copyright © 2016 Elsevier Ltd. All rights reserved.

On the Construction of Sorted Reactive Systems

DEFF Research Database (Denmark)

Birkedal, Lars; Debois, Søren; Hildebrandt, Thomas

2008-01-01

We develop a theory of sorted bigraphical reactive systems. Every application of bigraphs in the literature has required an extension, a sorting, of pure bigraphs. In turn, every such application has required a redevelopment of the theory of pure bigraphical reactive systems for the sorting at hand...... bigraphs. Technically, we give our construction for ordinary reactive systems, then lift it to bigraphical reactive systems. As such, we give also a construction of sortings for ordinary reactive systems. This construction is an improvement over previous attempts in that it produces smaller and much more...

Errors in Postural Preparation Lead to Increased Choice Reaction Times for Step Initiation in Older Adults

Science.gov (United States)

Nutt, John G.; Horak, Fay B.

2011-01-01

Background. This study asked whether older adults were more likely than younger adults to err in the initial direction of their anticipatory postural adjustment (APA) prior to a step (indicating a motor program error), whether initial motor program errors accounted for reaction time differences for step initiation, and whether initial motor program errors were linked to inhibitory failure. Methods. In a stepping task with choice reaction time and simple reaction time conditions, we measured forces under the feet to quantify APA onset and step latency and we used body kinematics to quantify forward movement of center of mass and length of first step. Results. Trials with APA errors were almost three times as common for older adults as for younger adults, and they were nine times more likely in choice reaction time trials than in simple reaction time trials. In trials with APA errors, step latency was delayed, correlation between APA onset and step latency was diminished, and forward motion of the center of mass prior to the step was increased. Participants with more APA errors tended to have worse Stroop interference scores, regardless of age. Conclusions. The results support the hypothesis that findings of slow choice reaction time step initiation in older adults are attributable to inclusion of trials with incorrect initial motor preparation and that these errors are caused by deficits in response inhibition. By extension, the results also suggest that mixing of trials with correct and incorrect initial motor preparation might explain apparent choice reaction time slowing with age in upper limb tasks. PMID:21498431

Performance of an attention-demanding task during treadmill walking shifts the noise qualities of step-to-step variation in step width.

Science.gov (United States)

Grabiner, Mark D; Marone, Jane R; Wyatt, Marilynn; Sessoms, Pinata; Kaufman, Kenton R

2018-06-01

The fractal scaling evident in the step-to-step fluctuations of stepping-related time series reflects, to some degree, neuromotor noise. The primary purpose of this study was to determine the extent to which the fractal scaling of step width, step width and step width variability are affected by performance of an attention-demanding task. We hypothesized that the attention-demanding task would shift the structure of the step width time series toward white, uncorrelated noise. Subjects performed two 10-min treadmill walking trials, a control trial of undisturbed walking and a trial during which they performed a mental arithmetic/texting task. Motion capture data was converted to step width time series, the fractal scaling of which were determined from their power spectra. Fractal scaling decreased by 22% during the texting condition (p Step width and step width variability increased 19% and five percent, respectively (p step width fractal scaling. The change of the fractal scaling of step width is consistent with increased cognitive demand and suggests a transition in the characteristics of the signal noise. This may reflect an important advance toward the understanding of the manner in which neuromotor noise contributes to some types of falls. However, further investigation of the repeatability of the results, the sensitivity of the results to progressive increases in cognitive load imposed by attention-demanding tasks, and the extent to which the results can be generalized to the gait of older adults seems warranted. Copyright © 2018 Elsevier B.V. All rights reserved.

A roadmap for OH reactivity research

Science.gov (United States)

Williams, Jonathan; Brune, William

2015-04-01

A fundamental property of the atmosphere is the frequency of gas-phase reactions with the OH radical, the atmosphere's primary oxidizing agent. This reaction frequency is called the OH reactivity and is the inverse the lifetime of the OH radical itself, which varies from a few seconds in the clean upper troposphere to below 10 ms in forests and polluted city environments. Ever since the discovery of the OH radical's importance to tropospheric chemistry, the characterization of its overall loss rate (OH reactivity) has remained a key question. At first, this property was assessed by summing the reactivity contributions of individually measured compounds; however, as improving analytical technology revealed ever more reactive species in ambient air, it became clear that this approach could provide only a lower limit. Approximately 15 years ago, the direct measurement of total OH reactivity was conceived independently by two groups. The first publications demonstrated direct OH reactivity measurements in the laboratory (Calpini et al., 1999) based on LIDAR and in the ambient air (Kovacs and Brune, 2001) based on in situ laser induced fluorescence detection of OH.

Borylnitrenes: electrophilic reactive intermediates with high reactivity towards C-H bonds.

Science.gov (United States)

Bettinger, Holger F; Filthaus, Matthias

2010-12-21

Borylnitrenes (catBN 3a and pinBN 3b; cat = catecholato, pin = pinacolato) are reactive intermediates that show high tendency towards insertion into the C-H bonds of unactivated hydrocarbons. The present article summarizes the matrix isolation investigations that were aimed at identifying, characterizing and investigating the chemical behaviour of 3a by spectroscopic means, and of the experiments in solution and in the gas phase that were performed with 3b. Comparison with the reactivity reported for difluorovinylidene 1a in solid argon indicates that 3a shows by and large similar reactivity, but only after photochemical excitation. The derivative 3b inserts into the C-H bonds of hydrocarbon solvents in high yields and thus allows the formation of primary amines, secondary amines, or amides from "unreactive" hydrocarbons. It can also be used for generation of methylamine or methylamide from methane in the gas phase at room temperature. Remaining challenges in the chemistry of borylnitrenes are briefly summarized.

Effects of direct injection timing and blending ratio on RCCI combustion with different low reactivity fuels

International Nuclear Information System (INIS)

Benajes, Jesús; Molina, Santiago; García, Antonio; Monsalve-Serrano, Javier

2015-01-01

Highlights: • E85 requires notable lower premixed energy ratios to achieve a stable combustion. • E10-95 leads to shorter and advanced combustion with higher maximum RoHR peaks. • E20-95, E10-98 and E10-95 reach EURO VI NOx and soot levels for all the engine loads. • E10-95 allows a significant reduction in HC and CO emissions. - Abstract: This work investigates the effects of the direct injection timing and blending ratio on RCCI performance and engine-out emissions at different engine loads using four low reactivity fuels: E10-95, E10-98, E20-95 and E85 (port fuel injected) and keeping constant the same high reactivity fuel: diesel B7 (direct injected). The experiments were conducted using a heavy-duty single-cylinder research diesel engine adapted for dual-fuel operation. All the tests were carried out at 1200 rpm. To assess the blending ratio effect, the total energy delivered to the cylinder coming from the low reactivity fuel was kept constant for the different fuel blends investigated by adjusting the low reactivity fuel mass as required in each case. In addition, a detailed analysis of the air/fuel mixing process has been developed by means of a 1-D in-house developed spray model. Results suggest that notable higher diesel amount is required to achieve a stable combustion using E85. This fact leads to higher NOx levels and unacceptable ringing intensity. By contrast, EURO VI NOx and soot levels are fulfilled with E20-95, E10-98 and E10-95. Finally, the higher reactivity of E10-95 results in a significant reduction in CO and HC emissions, mainly at low load

Pay-as-bid based reactive power market

International Nuclear Information System (INIS)

Amjady, N.; Rabiee, A.; Shayanfar, H.A.

2010-01-01

In energy market clearing, the offers are stacked in increasing order and the offer that intersects demand curve, determines the market clearing price (MCP). In reactive power market, the location of reactive power compensator is so important. A low cost reactive producer may not essentially be favorable if it is far from the consumer. Likewise, a high cost local reactive compensator at a heavily loaded demand center of network could be inevitably an alternative required to produce reactive power to maintain the integrity of power system. Given the background, this paper presents a day-ahead reactive power market based on pay-as-bid (PAB) mechanism. Generators expected payment function (EPF) is used to construct a bidding framework. Then, total payment function (TPF) of generators is used as the objective function of optimal power flow (OPF) problem to clear the PAB based market. The CIGRE-32 bus test system is used to examine the effectiveness of the proposed reactive power market.

Pay-as-bid based reactive power market

Energy Technology Data Exchange (ETDEWEB)

Amjady, N. [Department of Electrical Engineering, Semnan University, Semnan (Iran, Islamic Republic of); Rabiee, A., E-mail: Rabiee@iust.ac.i [Center of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Shayanfar, H.A. [Center of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

2010-02-15

In energy market clearing, the offers are stacked in increasing order and the offer that intersects demand curve, determines the market clearing price (MCP). In reactive power market, the location of reactive power compensator is so important. A low cost reactive producer may not essentially be favorable if it is far from the consumer. Likewise, a high cost local reactive compensator at a heavily loaded demand center of network could be inevitably an alternative required to produce reactive power to maintain the integrity of power system. Given the background, this paper presents a day-ahead reactive power market based on pay-as-bid (PAB) mechanism. Generators expected payment function (EPF) is used to construct a bidding framework. Then, total payment function (TPF) of generators is used as the objective function of optimal power flow (OPF) problem to clear the PAB based market. The CIGRE-32 bus test system is used to examine the effectiveness of the proposed reactive power market.

Should adjustment disorder be conceptualized as transitional disorder? In pursuit of adjustment disorders definition.

Science.gov (United States)

Israelashvili, Moshe

2012-12-01

The DSM classification of an adjustment disorder is frequently criticized for not being well differentiated from other disorders. A possible reason for this is the vague definition of the term adjustment in social science literature. Hence, the current paper discusses the definition of adjustment and its implications for understanding maladjustment. Differential definitions of the terms adjustment, adaptation, socialization and coping are outlined, leading to the proposition that each one of them represents a different type of demand that is imposed on an individual who encounters a transitional event. Moreover, the four types of demands might be the possible sources of maladjustment. Helping people in transition requires an identification of the source, or combination of sources, that have led to the adjustment problem first, followed by the implementation of an adequate helping approach.

Effect of One-Step and Multi-Steps Polishing System on Enamel Roughness

Directory of Open Access Journals (Sweden)

Cynthia Sumali

2013-07-01

Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 The final procedures of orthodontic treatment are bracket debonding and cleaning the remaining adhesive. Multi-step polishing system is the most common method used. The disadvantage of that system is long working time, because of the stages that should be done. Therefore, dental material manufacturer make an improvement to the system, to reduce several stages into one stage only. This new system is known as one-step polishing system. Objective: To compare the effect of one-step and multi-step polishing system on enamel roughness after orthodontic bracket debonding. Methods: Randomized control trial was conducted included twenty-eight maxillary premolar randomized into two polishing system; one-step OptraPol (Ivoclar, Vivadent and multi-step AstroPol (Ivoclar, Vivadent. After bracket debonding, the remaining adhesive on each group was cleaned by subjective polishing system for ninety seconds using low speed handpiece. The enamel roughness was subjected to profilometer, registering two roughness parameters (Ra, Rz. Independent t-test was used to analyze the mean score of enamel roughness in each group. Results: There was no significant difference of enamel roughness between one-step and multi-step polishing system (p>0.005. Conclusion: One-step polishing system can produce a similar enamel roughness to multi-step polishing system after bracket debonding and adhesive cleaning.DOI: 10.14693/jdi.v19i3.136

Does high C-reactive protein concentration increase atherosclerosis? The Whitehall II Study.

Directory of Open Access Journals (Sweden)

Mika Kivimäki

Full Text Available BACKGROUND: C-reactive protein (CRP, a marker of systemic inflammation, is associated with risk of coronary events and sub-clinical measures of atherosclerosis. Evidence in support of this link being causal would include an association robust to adjustments for confounders (multivariable standard regression analysis and the association of CRP gene polymorphisms with atherosclerosis (Mendelian randomization analysis. METHODOLOGY/PRINCIPAL FINDINGS: We genotyped 3 tag single nucleotide polymorphisms (SNPs [+1444T>C (rs1130864; +2303G>A (rs1205 and +4899T>G (rs 3093077] in the CRP gene and assessed CRP and carotid intima-media thickness (CIMT, a structural marker of atherosclerosis, in 4941 men and women aged 50-74 (mean 61 years (the Whitehall II Study. The 4 major haplotypes from the SNPs were consistently associated with CRP level, but not with other risk factors that might confound the association between CRP and CIMT. CRP, assessed both at mean age 49 and at mean age 61, was associated both with CIMT in age and sex adjusted standard regression analyses and with potential confounding factors. However, the association of CRP with CIMT attenuated to the null with adjustment for confounding factors in both prospective and cross-sectional analyses. When examined using genetic variants as the instrument for serum CRP, there was no inferred association between CRP and CIMT. CONCLUSIONS/SIGNIFICANCE: Both multivariable standard regression analysis and Mendelian randomization analysis suggest that the association of CRP with carotid atheroma indexed by CIMT may not be causal.

Structure-Reactivity Relationships in Multi-Component Transition Metal Oxide Catalysts FINAL Report

Energy Technology Data Exchange (ETDEWEB)

Altman, Eric I. [Yale Univ., New Haven, CT (United States)

2015-10-06

The focus of the project was on developing an atomic-level understanding of how transition metal oxide catalysts function. Over the course of several renewals the specific emphases shifted from understanding how local structure and oxidation state affect how molecules adsorb and react on the surfaces of binary oxide crystals to more complex systems where interactions between different transition metal oxide cations in an oxide catalyst can affect reactivity, and finally to the impact of cluster size on oxide stability and reactivity. Hallmarks of the work were the use of epitaxial growth methods to create surfaces relevant to catalysis yet tractable for fundamental surface science approaches, and the use of scanning tunneling microscopy to follow structural changes induced by reactions and to pinpoint adsorption sites. Key early findings included the identification of oxidation and reduction mechanisms on a tungsten oxide catalyst surface that determine the sites available for reaction, identification of C-O bond cleavage as the rate limiting step in alcohol dehydration reactions on the tungsten oxide surface, and demonstration that reduction does not change the favored reaction pathway but rather eases C-O bond cleavage and thus reduces the reaction barrier. Subsequently, a new reconstruction on the anatase phase of TiO₂ relevant to catalysis was discovered and shown to create sites with distinct reactivity compared to other TiO₂ surfaces. Building on this work on anatase, the mechanism by which TiO₂ enhances the reactivity of vanadium oxide layers was characterized and it was found that the TiO₂ substrate can force thin vanadia layers to adopt structures they would not ordinarily form in the bulk which in turn creates differences in reactivity between supported layers and bulk samples. From there, the work progressed to studying well-defined ternary oxides where synergistic effects between the two cations can induce

Microsoft® Visual Basic® 2010 Step by Step

CERN Document Server

Halvorson, Michael

2010-01-01

Your hands-on, step-by-step guide to learning Visual Basic® 2010. Teach yourself the essential tools and techniques for Visual Basic® 2010-one step at a time. No matter what your skill level, you'll find the practical guidance and examples you need to start building professional applications for Windows® and the Web. Discover how to: Work in the Microsoft® Visual Studio® 2010 Integrated Development Environment (IDE)Master essential techniques-from managing data and variables to using inheritance and dialog boxesCreate professional-looking UIs; add visual effects and print supportBuild com

Synthesis and characterization of carboxymethyl potato starch and its application in reactive dye printing.

Science.gov (United States)

Zhang, Bing; Gong, Honghong; Lü, Shaoyu; Ni, Boli; Liu, Mingzhu; Gao, Chunmei; Huang, Yinjuan; Han, Fei

2012-11-01

Carboxymethyl potato starch (CMPS) was synthesized with a simple dry and multi-step method as a product of the reaction of native potato starch and monochloroacetic acid in the presence of sodium hydroxide. The influence of the molar ratio of sodium hydroxide to anhydroglucose unit, the volume of 95% (v/v) ethanol, the rotation rate of motor driven stirrer and the reaction time for degree of substitution (DS) were evaluated. The product was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffractometry (XRD). FTIR spectrometry showed new bonds at 1618 and 1424 cm⁻¹ when native starch underwent carboxymethylation. SEM pictures showed that the smooth surface of native starch particles was mostly ruptured. XRD revealed that starch crystallinity was reduced after carboxymethylation. The viscosity of the mixture paste of carboxymethyl starch and sodium alginate (SA) was measured using a rotational viscometer. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with SA. And the results indicated that the mixed paste could partially replace SA as thickener in reactive dye printing. The study also showed that the method was low cost and eco-friendly and the product would have an extensive application in reactive dye printing. Copyright © 2012 Elsevier B.V. All rights reserved.

Analysis of excess reactivity of JOYO MK-III performance test core

International Nuclear Information System (INIS)

Maeda, Shigetaka; Yokoyama, Kenji

2003-10-01

JOYO is currently being upgraded to the high performance irradiation bed JOYO MK-III core'. The MK-III core is divided into two fuel regions with different plutonium contents. To obtain a higher neutron flux, the active core height was reduced from 55 cm to 50 cm. The reflector subassemblies were replaced by shielding subassemblies in the outer two rows. Twenty of the MK-III outer core fuel subassemblies in the performance test core were partially burned in the transition core. Four irradiation test rigs, which do not contain any fuel material, were loaded in the center of the performance test core. In order to evaluate the excess reactivity of MK-III performance test core accurately, we evaluated it by applying not only the JOYO MK-II core management code system MAGI, but also the MK-III core management code system HESTIA, the JUPITER standard analysis method and the Monte Carlo method with JFS-3-J3.2R content set. The excess reactivity evaluations obtained by the JUPITER standard analysis method were corrected to results based on transport theory with zero mesh-size in space and angle. A bias factor based on the MK-II 35th core, which sensitivity was similar to MK-III performance test core's, was also applied, except in the case where an adjusted nuclear cross-section library was used. Exact three-dimensional, pin-by-pin geometry and continuous-energy cross sections were used in the Monte Carlo calculation. The estimated error components associated with cross-sections, methods correction factors and the bias factor were combined based on Takeda's theory. Those independently calculated values agree well and range from 2.8 to 3.4%Δk/kk'. The calculation result of the MK-III core management code system HESTLA was 3.13% Δk/kk'. The estimated errors for bias method range from 0.1 to 0.2%Δk/kk'. The error in the case using adjusted cross-section was 0.3%Δk/kk'. (author)

Adjustable Pitot Probe

Science.gov (United States)

Ashby, George C., Jr.; Robbins, W. Eugene; Horsley, Lewis A.

1991-01-01

Probe readily positionable in core of uniform flow in hypersonic wind tunnel. Formed of pair of mating cylindrical housings: transducer housing and pitot-tube housing. Pitot tube supported by adjustable wedge fairing attached to top of pitot-tube housing with semicircular foot. Probe adjusted both radially and circumferentially. In addition, pressure-sensing transducer cooled internally by water or other cooling fluid passing through annulus of cooling system.

Early childhood cortisol reactivity moderates the effects of parent-child relationship quality on the development of children’s temperament in early childhood

Science.gov (United States)

Kopala-Sibley, Daniel C.; Dougherty, Lea R.; Dyson, Margret W.; Laptook, Rebecca S.; Olino, Thomas M.; Bufferd, Sara J.; Klein, Daniel N.

2017-01-01

Positive parenting has been related both to lower cortisol reactivity and more adaptive temperament traits in children, whereas elevated cortisol reactivity may be related to maladaptive temperament traits, such as higher negative emotionality (NE) and lower positive emotionality (PE). However, no studies have examined whether hypothalamic-pituitary-adrenal axis activity, as measured by cortisol reactivity, moderates the effect of the quality of the parent-child relationship on changes in temperament in early childhood. In this study, 126 3-year olds were administered the Laboratory Temperament Assessment Battery (Lab-TAB; Goldsmith et al., 1995) as a measure of temperamental NE and PE. Salivary cortisol was collected from the child at 4 time points during this task. The primary parent and the child completed the Teaching Tasks battery (Egeland et al., 1995), from which the quality of the relationship was coded. At age 6, children completed the Lab-TAB again. From age 3 to 6, adjusting for age 3 PE or NE, a better quality relationship with their primary parent predicted decreases in NE for children with elevated cortisol reactivity and predicted increases in PE for children with low cortisol reactivity. Results have implications for our understanding of the interaction of biological stress systems and the parent-child relationship in the development of temperament in childhood. PMID:26689860