Effects of market, e-marketing, and technology orientations on innovativeness and performance in Turkish health organizations.

PubMed

Mutlu, Hanifi Murat; Sürer, Atilla

2016-01-01

This article investigates the effects of strategic orientation on innovativeness and performance in health organizations in Turkey. We test hypotheses that market, e-marketing, and technology orientations positively affect innovativeness and performance. Market and technology orientations are found not have a significant effect on performance, but e-marketing orientation and innovativeness have a significant and positive effect. We also investigate indirect effects on innovativeness and performance. The analyses of direct and indirect effects are an important contribution to understanding relationships among research variables.

Field-controlled structures in ferromagnetic cholesteric liquid crystals.

PubMed

Medle Rupnik, Peter; Lisjak, Darja; Čopič, Martin; Čopar, Simon; Mertelj, Alenka

2017-10-01

One of the advantages of anisotropic soft materials is that their structures and, consequently, their properties can be controlled by moderate external fields. Whereas the control of materials with uniform orientational order is straightforward, manipulation of systems with complex orientational order is challenging. We show that a variety of structures of an interesting liquid material, which combine chiral orientational order with ferromagnetic one, can be controlled by a combination of small magnetic and electric fields. In the suspensions of magnetic nanoplatelets in chiral nematic liquid crystals, the platelet's magnetic moments orient along the orientation of the liquid crystal and, consequently, the material exhibits linear response to small magnetic fields. In the absence of external fields, orientations of the liquid crystal and magnetization have wound structure, which can be either homogeneously helical, disordered, or ordered in complex patterns, depending on the boundary condition at the surfaces and the history of the sample. We demonstrate that by using different combinations of small magnetic and electric fields, it is possible to control reversibly the formation of the structures in a layer of the material. In such a way, different periodic structures can be explored and some of them may be suitable for photonic applications. The material is also a convenient model system to study chiral magnetic structures, because it is a unique liquid analog of a solid helimagnet.

Individualism-Collectivism, Social Self-Control and Adolescent Substance Use and Risky Sexual Behavior.

PubMed

Pokhrel, Pallav; Bennett, Brooke L; Regmi, Sakshi; Idrisov, Bulat; Galimov, Artur; Akhmadeeva, Leila; Sussman, Steve

2018-06-07

Individualism and collectivism are cultural syndromes that have been associated with adolescent problem behavior in studies conducted in the U.S. and Southeast Asia. However, research investigating the mechanisms of how cultural orientation impacts health risk behaviors has been limited. This study tested a new model explaining the relationship between cultural orientation (i.e., individualism, collectivism) and adolescent problem behavior (i.e., substance use and risky sex) in terms of interpersonal self-regulation (i.e., social self-control). As such, the study is rooted in theories of the role of culture in developing self-regulation. Participants were high school students (N = 716) from the Bashkirtostan Republic of the Russian Federation. Adolescents from the Russian Federation tend to show high prevalence of cigarette smoking and binge drinking. People of the Russian Federation in general are traditionally collectivist in orientation, although increased globalization and post-Soviet capitalism may indicate high individualist values in younger generation Russians. Using path analysis we found that in addition to having direct effects, higher individualism indirectly affected substance use and risky sexual behavior through social self-control and negative life events. Higher collectivism was found to have a direct protective effect on risky sexual behavior and a direct effect on social self-control. However, collectivism was not found to have indirect effects on substance use or risky sexual behavior. Higher individualism appears to function as a risk factor for adolescent problem behavior and this relationship may be mediated by lower social self-control. Culturally-tailored prevention programs utilizing the individualism-collectivism framework may benefit from addressing social self-control.

The field efficacy of garlic extract against Dermanyssus gallinae in layer farms of Babol, Iran.

PubMed

Faghihzadeh Gorji, Shohreh; Faghihzadeh Gorji, Sina; Rajabloo, Mohammad

2014-03-01

Dermanyssus gallinae (Acari: Mesostigmata) is the most important hematophagous ectoparasite in layer farms in many countries. The reproduction rate of the parasite is rapid and can be completed in a week under favorable conditions. The parasite has direct and indirect effects on birds. It can also act as a vector for some important pathogens. Many researchers have investigated the effects of essential oils, plant extracts, oriental medicinal plant extracts, and silica against red mite. They can be used as killing agents or repellents. In the present study, the effect of garlic (Allium sativum) extract was investigated for controlling red mite infestation in a layer farm in Babol, North of Iran. Our results showed that the extract was effective and we obtained a 96% success after two successive sprays.

Fluid driven fracture mechanics in highly anisotropic shale: a laboratory study with application to hydraulic fracturing

NASA Astrophysics Data System (ADS)

Gehne, Stephan; Benson, Philip; Koor, Nick; Enfield, Mark

2017-04-01

The finding of considerable volumes of hydrocarbon resources within tight sedimentary rock formations in the UK led to focused attention on the fundamental fracture properties of low permeability rock types and hydraulic fracturing. Despite much research in these fields, there remains a scarcity of available experimental data concerning the fracture mechanics of fluid driven fracturing and the fracture properties of anisotropic, low permeability rock types. In this study, hydraulic fracturing is simulated in a controlled laboratory environment to track fracture nucleation (location) and propagation (velocity) in space and time and assess how environmental factors and rock properties influence the fracture process and the developing fracture network. Here we report data on employing fluid overpressure to generate a permeable network of micro tensile fractures in a highly anisotropic shale ( 50% P-wave velocity anisotropy). Experiments are carried out in a triaxial deformation apparatus using cylindrical samples. The bedding planes are orientated either parallel or normal to the major principal stress direction (σ1). A newly developed technique, using a steel guide arrangement to direct pressurised fluid into a sealed section of an axially drilled conduit, allows the pore fluid to contact the rock directly and to initiate tensile fractures from the pre-defined zone inside the sample. Acoustic Emission location is used to record and map the nucleation and development of the micro-fracture network. Indirect tensile strength measurements at atmospheric pressure show a high tensile strength anisotropy ( 60%) of the shale. Depending on the relative bedding orientation within the stress field, we find that fluid induced fractures in the sample propagate in two of the three principal fracture orientations: Divider and Short-Transverse. The fracture progresses parallel to the bedding plane (Short-Transverse orientation) if the bedding plane is aligned (parallel) with the direction of σ1. Conversely, the crack plane develops perpendicular to the bedding plane, if the bedding plane is orientated normal to σ1. Fracture initiation pressures are higher in the Divider orientation ( 24MPa) than in the Short-Transverse orientation ( 14MPa) showing a tensile strength anisotropy ( 42%) comparable to ambient tensile strength results. We then use X-Ray Computed Tomography (CT) 3D-images to evaluate the evolved fracture network in terms of fracture pattern, aperture and post-test water permeability. For both fracture orientations, very fine, axial fractures evolve over the entire length of the sample. For the fracturing in the Divider orientation, it has been observed, that in some cases, secondary fractures are branching of the main fracture. Test data from fluid driven fracturing experiments suggest that fracture pattern, fracture propagation trajectories and fracturing fluid pressure (initiation and propagation pressure) are predominantly controlled by the interaction between the anisotropic mechanical properties of the shale and the anisotropic stress environment. The orientation of inherent rock anisotropy relative to the principal stress directions seems to be the main control on fracture orientation and required fracturing pressure.

Indirect decentralized repetitive control

NASA Technical Reports Server (NTRS)

Lee, Soo Cheol; Longman, Richard W.

1993-01-01

Learning control refers to controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented a theory of indirect decentralized learning control based on use of indirect adaptive control concepts employing simultaneous identification and control. This paper extends these results to apply to the indirect repetitive control problem in which a periodic (i.e., repetitive) command is given to a control system. Decentralized indirect repetitive control algorithms are presented that have guaranteed convergence to zero tracking error under very general conditions. The original motivation of the repetitive control and learning control fields was learning in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the desired trajectory. Decentralized repetitive control is natural for this application because the feedback control for link rotations is normally implemented in a decentralized manner, treating each link as if it is independent of the other links.

Speed Sensorless Induction Motor Drives for Electrical Actuators: Schemes, Trends and Tradeoffs

NASA Technical Reports Server (NTRS)

Elbuluk, Malik E.; Kankam, M. David

1997-01-01

For a decade, induction motor drive-based electrical actuators have been under investigation as potential replacement for the conventional hydraulic and pneumatic actuators in aircraft. Advantages of electric actuator include lower weight and size, reduced maintenance and operating costs, improved safety due to the elimination of hazardous fluids and high pressure hydraulic and pneumatic actuators, and increased efficiency. Recently, the emphasis of research on induction motor drives has been on sensorless vector control which eliminates flux and speed sensors mounted on the motor. Also, the development of effective speed and flux estimators has allowed good rotor flux-oriented (RFO) performance at all speeds except those close to zero. Sensorless control has improved the motor performance, compared to the Volts/Hertz (or constant flux) controls. This report evaluates documented schemes for speed sensorless drives, and discusses the trends and tradeoffs involved in selecting a particular scheme. These schemes combine the attributes of the direct and indirect field-oriented control (FOC) or use model adaptive reference systems (MRAS) with a speed-dependent current model for flux estimation which tracks the voltage model-based flux estimator. Many factors are important in comparing the effectiveness of a speed sensorless scheme. Among them are the wide speed range capability, motor parameter insensitivity and noise reduction. Although a number of schemes have been proposed for solving the speed estimation, zero-speed FOC with robustness against parameter variations still remains an area of research for speed sensorless control.

Waveform control of orientation-dependent ionization of DCl in few-cycle laser fields.

PubMed

Znakovskaya, I; von den Hoff, P; Schirmel, N; Urbasch, G; Zherebtsov, S; Bergues, B; de Vivie-Riedle, R; Weitzel, K-M; Kling, M F

2011-05-21

Strong few-cycle light fields with stable electric field waveforms allow controlling electrons on time scales down to the attosecond domain. We have studied the dissociative ionization of randomly oriented DCl in 5 fs light fields at 720 nm in the tunneling regime. Momentum distributions of D(+) and Cl(+) fragments were recorded via velocity-map imaging. A waveform-dependent anti-correlated directional emission of D(+) and Cl(+) fragments is observed. Comparison of our results with calculations indicates that tailoring of the light field via the carrier envelope phase permits the control over the orientation of DCl(+) and in turn the directional emission of charged fragments upon the breakup of the molecular ion. © The Owner Societies 2011

SiN-SiC nanofilm: A nano-functional ceramic with bipolar magnetic semiconducting character

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

Zhang, Jiahui; Li, Xingxing; Yang, Jinlong, E-mail: jlyang@ustc.edu.cn

2014-04-28

Nowadays, functional ceramics have been largely explored for application in various fields. However, magnetic functional ceramics for spintronics remain little studied. Here, we propose a nano-functional ceramic of sphalerite SiN-SiC nanofilm with intrinsic ferromagnetic order. Based on first principles calculations, the SiN-SiC nanofilm is found to be a ferromagnetic semiconductor with an indirect band gap of 1.71 eV. By mean field theory, the Curie temperature is estimated to be 304 K, close to room temperature. Furthermore, the valence band and conduction band states of the nanofilm exhibit inverse spin-polarization around the Fermi level. Thus, the SiN-SiC nanofilm is a typical bipolar magneticmore » semiconductor in which completely spin-polarized currents with reversible spin polarization can be created and controlled by applying a gate voltage. Such a nano-functional ceramic provides a possible route for electrical manipulation of carrier's spin orientation.« less

High-precision control of static magnetic field magnitude, orientation, and gradient using optically pumped vapour cell magnetometry.

PubMed

Ingleby, S J; Griffin, P F; Arnold, A S; Chouliara, M; Riis, E

2017-04-01

An integrated system of hardware and software allowing precise definition of arbitrarily oriented magnetic fields up to |B| = 1 μT within a five-layer Mumetal shield is described. The system is calibrated with reference to magnetic resonance observed between Zeeman states of the 6S 1/2 F = 4 133 Cs ground state. Magnetic field definition over the full 4π solid angle is demonstrated with one-sigma tolerances in magnitude, orientation, and gradient of δ|B| = 0.94 nT, δθ = 5.9 mrad, and δ|∇B|=13.0 pT/mm, respectively. This field control is used to empirically map M x magnetometer signal amplitude as a function of the static field (B 0 ) orientation.

Direct and indirect pathways for choosing objects and actions.

PubMed

Hikosaka, Okihide; Kim, Hyoung F; Amita, Hidetoshi; Yasuda, Masaharu; Isoda, Masaki; Tachibana, Yoshihisa; Yoshida, Atsushi

2018-02-23

A prominent target of the basal ganglia is the superior colliculus (SC) which controls gaze orientation (saccadic eye movement in primates) to an important object. This 'object choice' is crucial for choosing an action on the object. SC is innervated by the substantia nigra pars reticulata (SNr) which is controlled mainly by the caudate nucleus (CD). This CD-SNr-SC circuit is sensitive to the values of individual objects and facilitates saccades to good objects. The object values are processed differently in two parallel circuits: flexibly by the caudate head (CDh) and stably by the caudate tail (CDt). To choose good objects, we need to reject bad objects. In fact, these contrasting functions are accomplished by the circuit originating from CDt: The direct pathway focuses on good objects and facilitates saccades to them; the indirect pathway focuses on bad objects and suppresses saccades to them. Inactivation of CDt deteriorated the object choice, because saccades to bad objects were no longer suppressed. This suggests that the indirect pathway is important for object choice. However, the direct and indirect pathways for 'object choice', which aim at the same action (i.e., saccade), may not work for 'action choice'. One possibility is that circuits controlling different actions are connected through the indirect pathway. Additional connections of the indirect pathway with brain areas outside the basal ganglia may also provide a wider range of behavioral choice. In conclusion, basal ganglia circuits are composed of the basic direct/indirect pathways and additional connections and thus have acquired multiple functions. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Research on the Mode of Technology Innovation Alliance of the New Material Industry in Hunan Province

NASA Astrophysics Data System (ADS)

Wang, Fan

2018-03-01

One of the main directions of technology development in the 21st century is the development and application of new materials, and the key to the development of the new material industry lies in the industrial technology innovation. The gross scale of the new material industry in Hunan Province ranks the first array in China. Based on the present situation of Hunan’s new material industry, three modes of technology innovation alliance are put forward in this paper, namely the government-driven mode, the research-driven and the market-oriented mode. The government-driven mode is applicable to the major technology innovation fields with uncertain market prospect, high risk of innovation and government’s direct or indirect intervention;the research-driven mode is applicable to the key technology innovation fields with a high technology content; and the market-oriented mode is applicable to the general innovation fields in which enterprises have demands for technology innovation but such innovation must be achieved via cooperative research and development.

Coherent Excitation of Optical Phonons in GaAs by Broadband Terahertz Pulses

PubMed Central

Fu, Zhengping; Yamaguchi, Masashi

2016-01-01

Coherent excitation and control of lattice motion by electromagnetic radiation in optical frequency range has been reported through variety of indirect interaction mechanisms with phonon modes. However, coherent phonon excitation by direct interaction of electromagnetic radiation and nuclei has not been demonstrated experimentally in terahertz (THz) frequency range mainly due to the lack of THz emitters with broad bandwidth suitable for the purpose. We report the experimental observation of coherent phonon excitation and detection in GaAs using ultrafast THz-pump/optical-probe scheme. From the results of THz pump field dependence, pump/probe polarization dependence, and crystal orientation dependence, we attributed THz wave absorption and linear electro-optic effect to the excitation and detection mechanisms of coherent polar TO phonons. Furthermore, the carrier density dependence of the interaction of coherent phonons and free carriers is reported. PMID:27905563

Post-Newtonian direct and mixed orbital effects due to the oblateness of the central body

NASA Astrophysics Data System (ADS)

Iorio, L.

2015-06-01

The orbital dynamics of a test particle moving in the nonspherically symmetric field of a rotating oblate primary is impacted also by certain indirect, mixed effects arising from the interplay of the different Newtonian and post-Newtonian accelerations which induce known direct perturbations. We systematically calculate the indirect gravitoelectromagnetic shifts per orbit of the Keplerian orbital elements of the test particle arising from the crossing among the first even zonal harmonic J2 of the central body and the post-Newtonian static and stationary components of its gravitational field. We also work out the Newtonian shifts per orbit of order J22, and the direct post-Newtonian gravitoelectric effects of order J2c-2 arising from the equations of motion. In the case of both the indirect and direct gravitoelectric J2c-2 shifts, our calculation holds for an arbitrary orientation of the symmetry axis of the central body. We yield numerical estimates of their relative magnitudes for systems ranging from Earth's artificial satellites to stars orbiting supermassive black holes. As far as their measurability is concerned, highly elliptical orbital configuration are desirable.

Magnetic field-directed hybrid anisotropic nanocomposites.

PubMed

Gong, Maogang; Zhang, Jingming; Ren, Shenqiang

2018-08-24

A facile bottom-up approach is developed to grow magnetic metallic Cu/FeCo (core/shell) nanowires, where their distribution and orientation can be controlled by magnetic field. The nanocomposites consisting of a ferroelectric polymer matrix and magnetic nanowire arrays exhibit the orientation-controlled anisotropy and interfacial magnetoelectric coupling effect.

Optimal control of orientation and entanglement for two dipole-dipole coupled quantum planar rotors.

PubMed

Yu, Hongling; Ho, Tak-San; Rabitz, Herschel

2018-05-09

Optimal control simulations are performed for orientation and entanglement of two dipole-dipole coupled identical quantum rotors. The rotors at various fixed separations lie on a model non-interacting plane with an applied control field. It is shown that optimal control of orientation or entanglement represents two contrasting control scenarios. In particular, the maximally oriented state (MOS) of the two rotors has a zero entanglement entropy and is readily attainable at all rotor separations. Whereas, the contrasting maximally entangled state (MES) has a zero orientation expectation value and is most conveniently attainable at small separations where the dipole-dipole coupling is strong. It is demonstrated that the peak orientation expectation value attained by the MOS at large separations exhibits a long time revival pattern due to the small energy splittings arising form the extremely weak dipole-dipole coupling between the degenerate product states of the two free rotors. Moreover, it is found that the peak entanglement entropy value attained by the MES remains largely unchanged as the two rotors are transported to large separations after turning off the control field. Finally, optimal control simulations of transition dynamics between the MOS and the MES reveal the intricate interplay between orientation and entanglement.

Direct and indirect determination of electrocaloric effect in Na0.5Bi0.5TiO3

NASA Astrophysics Data System (ADS)

Birks, E.; Dunce, M.; Peräntie, J.; Hagberg, J.; Sternberg, A.

2017-06-01

Direct and indirect studies of the electrocaloric effect were carried out in poled and depoled Na0.5Bi0.5TiO3. For this purpose, polarization and electrocaloric effect temperature change measurements were made at different electric field pulses as a function of temperature. The applicability of the widely used indirect electrocaloric effect determination method, using the Maxwell relation, was critically analyzed with respect to the reliable direct measurements. Quantitative differences were observed between the results obtained by both approaches in the case of the poled Na0.5Bi0.5TiO3 sample. These differences can be explained by the temperature-dependent concentration of domains oriented in the direction of the applied electric field. Whereas in depoled Na0.5Bi0.5TiO3, which is characterized by the electric field dependence of polar nanoregions embedded in a nonpolar matrix, the Maxwell relation is not applicable at all, as it is indicated by the obtained results. Possible mechanisms which could be responsible for the electrocaloric effect in the relaxor state were considered. The results of this study are used to evaluate the numerous results obtained and published by other authors, using the Maxwell relation to indirectly determine the electrocaloric effect. The reason for the negative values of the electrocaloric effect, obtained in such a way and widely discussed in the literature in the case of Na0.5Bi0.5TiO3, has been explained in this study.

The Direct and Indirect Effects of Parental Bonds, Parental Drug Use, and Self-Control on Adolescent Substance Use

ERIC Educational Resources Information Center

Hope,Trina L.; Whiteford, Scott W.

2005-01-01

Research indicates that parenting has important effects on adolescent substance use. However, the indirect effect of parenting on adolescent substance use via self-control is less understood. Gottfredson and Hirschi's General Theory of Crime has been extensively tested by researchers in the field of criminology, but the theory rarely has been used…

Closed-loop torque feedback for a universal field-oriented controller

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

De Doncker, R.W.A.A.; King, R.D.; Sanza, P.C.

A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation. 1 figure.

Closed-loop torque feedback for a universal field-oriented controller

DOEpatents

De Doncker, R.W.A.A.; King, R.D.; Sanza, P.C.; Haefner, K.B.

1992-11-24

A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation. 1 figure.

Closed-loop torque feedback for a universal field-oriented controller

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

De Doncker, Rik W. A. A.; King, Robert D.; Sanza, Peter C.

A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation.

Mammalian animal models of psychosexual differentiation: when is 'translation' to the human situation possible?

PubMed

Baum, Michael J

2006-11-01

Clinical investigators have been forced primarily to use experiments of nature (e.g., cloacal exstrophy; androgen insensitivity, congenital adrenal hyperplasia) to assess the contribution of fetal sex hormone exposure to the development of male- and female-typical profiles of gender identity and role behavior as well as sexual orientation. In this review, I summarize the results of numerous correlative as well as mechanistic animal experiments that shed significant light on general neuroendocrine mechanisms controlling the differentiation of neural circuits controlling sexual partner preference (sexual orientation) in mammalian species including man. I also argue, however, that results of animal studies can, at best, provide only indirect insights into the neuroendocrine determinants of human gender identity and role behaviors.

Useful oriented immobilization of antibodies on chimeric magnetic particles: direct correlation of biomacromolecule orientation with biological activity by AFM studies.

PubMed

Marciello, Marzia; Filice, Marco; Olea, David; Velez, Marisela; Guisan, José M; Mateo, Cesar

2014-12-16

The preparation and performance of a suitable chimeric biosensor based on antibodies (Abs) immobilized on lipase-coated magnetic particles by means of a standing orienting strategy are presented. This novel system is based on hydrophobic magnetic particles coated with modified lipase molecules able to orient and further immobilize different Abs in a covalent way without any previous site-selective chemical modification of biomacromolecules. Different key parameters attending the process were studied and optimized. The optimal preparation was performed using a controlled loading (1 nmol Ab g(-1) chimeric support) at pH 9 and a short reaction time to recover a biological activity of about 80%. AFM microscopy was used to study and confirm the Abs-oriented immobilization on lipase-coated magnetic particles and the final achievement of a highly active and recyclable chimeric immune sensor. This direct technique was demonstrated to be a powerful alternative to the indirect immunoactivity assay methods for the study of biomacromolecule-oriented immobilizations.

The Mediating Roles of Rejection Sensitivity and Proximal Stress in the Association Between Discrimination and Internalizing Symptoms Among Sexual Minority Women.

PubMed

Dyar, Christina; Feinstein, Brian A; Eaton, Nicholas R; London, Bonita

2018-01-01

The negative impact of discrimination on mental health among lesbian, gay, and bisexual populations has been well documented. However, the possible mediating roles of sexual orientation rejection sensitivity and rejection-based proximal stress in the association between discrimination and internalizing symptoms remain unclear. Rejection-based proximal stress is a subset of proximal stressors that are theorized to arise from concerns about and expectations of sexual orientation-based rejection and discrimination. Drawing on minority stress theory, we tested potential mediating effects using indirect effects structural equation modeling in a sample of 300 sexual minority women. Results indicated that the indirect effect of discrimination on internalizing symptoms (a latent variable indicated by depression and anxiety symptoms) through sexual orientation rejection sensitivity and rejection-based proximal stress (a latent variable indicated by preoccupation with stigma, concealment motivation, and difficulty developing a positive sexual identity) was significant. Additionally, the indirect effects of discrimination on rejection-based proximal stress through sexual orientation rejection sensitivity and of sexual orientation rejection sensitivity on internalizing symptoms through rejection-based proximal stress were also significant. These findings indicate that sexual orientation rejection sensitivity plays an important role in contributing to rejection-based proximal stress and internalizing symptoms among sexual minority women.

Posttraumatic Growth and Bereavement: The Contribution of Self-Determination Theory.

PubMed

Lumb, Andrew B; Beaudry, Myriam; Blanchard, Celine

2017-09-01

No research drawing from Self-Determination Theory has investigated the bereavement experience of individuals or how motivation can help facilitate posttraumatic growth (PTG) following the death of a loved one. In two cross-sectional studies, university students completed an online survey. Study 1 investigated the contribution of global autonomous and controlled motivation in statistically predicting PTG above and beyond previously researched correlates. Study 2 explored the mediating role of cognitive appraisals and coping in explaining the relationship between global motivation orientations and PTG. Results indicated that in comparison to controlled motivation, autonomous motivation was positively related PTG, even after controlling for previously researched correlates. Mediation results indicated an indirect effect of global autonomous motivation on PTG through task-oriented coping. Collectively, these findings suggest the importance of incorporating motivation into models of PTG. Clinical implications of these findings are also discussed.

Vibration control of a ship engine system using high-load magnetorheological mounts associated with a new indirect fuzzy sliding mode controller

NASA Astrophysics Data System (ADS)

Phu, Do Xuan; Choi, Seung-Bok

2015-02-01

In this work, a new high-load magnetorheological (MR) fluid mount system is devised and applied to control vibration in a ship engine. In the investigation of vibration-control performance, a new modified indirect fuzzy sliding mode controller is formulated and realized. The design of the proposed MR mount is based on the flow mode of MR fluid, and it includes two separated coils for generating a magnetic field. An optimization process is carried out to achieve maximal damping force under certain design constraints, such as the allowable height of the mount. As an actuating smart fluid, a new plate-like iron-particle-based MR fluid is used, instead of the conventional spherical iron-particle-based MR fluid. After evaluating the field-dependent yield stress of the MR fluid, the field-dependent damping force required to control unwanted vibration in the ship engine is determined. Subsequently, an appropriate-sized MR mount is manufactured and its damping characteristics are evaluated. After confirming the sufficient damping force level of the manufactured MR mount, a medium-sized ship engine mount system consisting of eight MR mounts is established, and its dynamic governing equations are derived. A new modified indirect fuzzy sliding mode controller is then formulated and applied to the engine mount system. The displacement and velocity responses show that the unwanted vibrations of the ship engine system can be effectively controlled in both the axial and radial directions by applying the proposed control methodology.

Effects of time perspective and self-control on procrastination and Internet addiction.

PubMed

Kim, Jinha; Hong, Hyeongi; Lee, Jungeun; Hyun, Myoung-Ho

2017-06-01

Background and aims College students experiencing stress show tendencies to procrastinate and can develop Internet addiction problems. This study investigated the structural relationship between time perspective and self-control on procrastination and Internet addiction. Methods College students (N = 377) residing in South Korea completed the following questionnaires: the Pathological Internet Use Behavior Symptom Scale for Adults, the Zimbardo Time Perspective Inventory, the Self-Control Rating Scale, and the Aitken Procrastination Inventory. The sample variance-covariance matrix was analyzed using AMOS 20.0. Results Time perspective had a direct effect on self-control and an indirect effect on Internet use and procrastination. In addition, self-control affected procrastination and Internet use. Conclusions Individuals with a present-oriented time perspective tend to evidence poorer self-control, increasing the likelihood of procrastination and Internet addiction. Individuals with a future-oriented time perspective, on the other hand, tend to have stronger self-control, decreasing their risk of procrastination and Internet addiction.

Effects of time perspective and self-control on procrastination and Internet addiction

PubMed Central

Kim, Jinha; Hong, Hyeongi; Lee, Jungeun; Hyun, Myoung-Ho

2017-01-01

Background and aims College students experiencing stress show tendencies to procrastinate and can develop Internet addiction problems. This study investigated the structural relationship between time perspective and self-control on procrastination and Internet addiction. Methods College students (N = 377) residing in South Korea completed the following questionnaires: the Pathological Internet Use Behavior Symptom Scale for Adults, the Zimbardo Time Perspective Inventory, the Self-Control Rating Scale, and the Aitken Procrastination Inventory. The sample variance–covariance matrix was analyzed using AMOS 20.0. Results Time perspective had a direct effect on self-control and an indirect effect on Internet use and procrastination. In addition, self-control affected procrastination and Internet use. Conclusions Individuals with a present-oriented time perspective tend to evidence poorer self-control, increasing the likelihood of procrastination and Internet addiction. Individuals with a future-oriented time perspective, on the other hand, tend to have stronger self-control, decreasing their risk of procrastination and Internet addiction. PMID:28494615

Methyl jasmonate-induction of cotton: a field test of the “attract and reward” strategy of conservation biological control

USDA-ARS?s Scientific Manuscript database

Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defense responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively impact herbivore survival, development, and fecundity. Indirect respons...

Male and Female University Students' Experiences of Indirect Aggression

ERIC Educational Resources Information Center

Leenaars, Lindsey; Rinaldi, Christina M.

2010-01-01

This study examines the role of sex, gender role orientation, social representations of indirect aggression, and indicators of psychosocial adjustment in indirect aggression and victimization in an emerging adult sample. A total of 42 participants (19 men, 23 women) recruited are required to complete the questionnaires, along with 18 participants…

Controlling Coaching Behaviors and Athlete Burnout: Investigating the Mediating Roles of Perfectionism and Motivation.

PubMed

Barcza-Renner, Kelly; Eklund, Robert C; Morin, Alexandre J; Habeeb, Christine M

2016-02-01

This investigation sought to replicate and extend earlier studies of athlete burnout by examining athlete-perceived controlling coaching behaviors and athlete perfectionism variables as, respectively, environmental and dispositional antecedents of athlete motivation and burnout. Data obtained from NCAA Division I swimmers (n = 487) within 3 weeks of conference championship meets were analyzed for this report. Significant indirect effects were observed between controlling coaching behaviors and burnout through athlete perfectionism (i.e., socially prescribed, self-oriented) and motivation (i.e., autonomous, amotivation). Controlling coaching behaviors predicted athlete perfectionism. In turn, self-oriented perfectionism was positively associated with autonomous motivation and negatively associated with amotivation, while socially prescribed perfectionism was negatively associated with autonomous motivation and positively associated with controlled motivation and amotivation. Autonomous motivation and amotivation, in turn, predicted athlete burnout in expected directions. These findings implicate controlling coaching behaviors as potentially contributing to athlete perfectionism, shaping athlete motivational regulations, and possibly increasing athlete burnout.

When death is not a problem: Regulating implicit negative affect under mortality salience.

PubMed

Lüdecke, Christina; Baumann, Nicola

2015-12-01

Terror management theory assumes that death arouses existential anxiety in humans which is suppressed in focal attention. Whereas most studies provide indirect evidence for negative affect under mortality salience by showing cultural worldview defenses and self-esteem strivings, there is only little direct evidence for implicit negative affect under mortality salience. In the present study, we assume that this implicit affective reaction towards death depends on people's ability to self-regulate negative affect as assessed by the personality dimension of action versus state orientation. Consistent with our expectations, action-oriented participants judged artificial words to express less negative affect under mortality salience compared to control conditions whereas state-oriented participants showed the reversed pattern. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Graphene levitation and orientation control using a magnetic field

NASA Astrophysics Data System (ADS)

Niu, Chao; Lin, Feng; Wang, Zhiming M.; Bao, Jiming; Hu, Jonathan

2018-01-01

This paper studies graphene levitation and orientation control using a magnetic field. The torques in all three spatial directions induced by diamagnetic forces are used to predict stable conditions for different shapes of millimeter-sized graphite plates. We find that graphite plates, in regular polygon shapes with an even number of sides, will be levitated in a stable manner above four interleaved permanent magnets. In addition, the orientation of micrometer-sized graphene flakes near a permanent magnet is studied in both air and liquid environments. Using these analyses, we are able to simulate optical transmission and reflection on a writing board and thereby reveal potential applications using this technology for display screens. Understanding the control of graphene flake orientation will lead to the discovery of future applications using graphene flakes.

Brief report: identity processes in Filipino late adolescents and young adults: parental influences and mental health outcomes.

PubMed

Pesigan, Ivan Jacob Agaloos; Luyckx, Koen; Alampay, Liane Peña

2014-07-01

This study focused on a process-oriented approach to identity formation using a sample of Filipino late adolescents and young adults (17-30 years; N = 779). Indirect relations between parenting and mental health via identity formation processes were examined. Two parenting dimensions (psychological control and support), two types of mental health outcomes (depression and psychological well-being), and five identity dimensions (commitment making (CM), identification with commitment (IC), exploration in breadth (EB), exploration in depth (ED), and ruminative exploration (RE)) were assessed. Recursive path analysis showed indirect relations between parenting and mental health via EB, ED, RE, and IC. Model differences between late adolescents (17-21 year olds) and young adults (22-30 year olds) were examined using multigroup path analysis. Results showed that the direct effect of psychological control on RE, and its indirect effect on depression through RE differed between the age groups. Implications and suggestions for future research are provided. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

A Longitudinal Analysis of the Indirect Effect of Violence Exposure on Future Orientation Through Perceived Stress and the Buffering Effect of Family Participation.

PubMed

Schmidt, Carissa J; Zimmerman, Marc A; Stoddard, Sarah A

2018-06-07

Exposure to violence (ETV) during adolescence has been associated with negative effects in later life, and may negatively affect an individual's future orientation. Future orientation has important health implications and warrants being studied. Yet, few researchers have examined how ETV affects an individual's future orientation as a young adult. The purpose of this study was to examine the indirect effect of ETV during adolescence on future orientation as a young adult through perceived stress. We also tested the moderating effect of family participation on the relationship between perceived stress and future orientation. Longitudinal data from a sample of 316 African American participants (42.10% male and 57.90% female, Mage = 14.76 at Wave 1) from low socioeconomic backgrounds recruited from a Midwestern school district were used in the analysis. Multigroup structural equation modeling (SEM) was used to test our hypotheses. Our findings indicated that greater ETV during adolescence is associated with higher levels of perceived stress and, in turn, a more negative outlook on one's future as a young adult. This indirect effect occurred for individuals with lower family participation, but was not evident for individuals with greater family participation. These findings provide important implications for youth development interventions. © Society for Community Research and Action 2018.

Coping as a Mediator Between Parental Attachment and Resilience: An Examination of Differential Effects Between Chinese Adolescents From Single Parent Families Versus Those From Intact Families.

PubMed

Guo, Xiamei

2018-01-01

The crude divorce rate has been increasing steadily for over a decade in China. Consequently, more and more children have to face the challenge of growing up in single parent families. The current study investigated the mediating effects of problem-oriented and emotion-oriented coping on the relationship between parental attachment and psychological resilience among a sample of Chinese adolescents from single parent families and intact families. Participants were 975 high school students (44.30% males; aged 15-19 years, M = 16.32 years, SD = 0.74), 871 from intact families and 104 from single parent families. Structural equation modeling showed that security in maternal attachment was positively associated with resilience through the indirect effect of reduced emotion-oriented coping among adolescents from single parent families. Among adolescents from intact families, security in maternal attachment was both directly associated with resilience and indirectly through enhanced problem-oriented and reduced emotion-oriented coping. Security in paternal attachment was associated with resilience both directly and indirectly through enhanced problem-oriented coping as well among those from intact families. Female adolescents exhibited significantly lower levels of resilience than male adolescents did regardless of the marital status of their parents. Limitations and suggestions for future research are discussed.

Controlling orientational order in block copolymers using low-intensity magnetic fields

PubMed Central

Choo, Youngwoo; Kawabata, Kohsuke; Kaufman, Gilad; Feng, Xunda; Di, Xiaojun; Rokhlenko, Yekaterina; Mahajan, Lalit H.; Ndaya, Dennis; Kasi, Rajeswari M.

2017-01-01

The interaction of fields with condensed matter during phase transitions produces a rich variety of physical phenomena. Self-assembly of liquid crystalline block copolymers (LC BCPs) in the presence of a magnetic field, for example, can result in highly oriented microstructures due to the LC BCP’s anisotropic magnetic susceptibility. We show that such oriented mesophases can be produced using low-intensity fields (<0.5 T) that are accessible using permanent magnets, in contrast to the high fields (>4 T) and superconducting magnets required to date. Low-intensity field alignment is enabled by the addition of labile mesogens that coassemble with the system’s nematic and smectic A mesophases. The alignment saturation field strength and alignment kinetics have pronounced dependences on the free mesogen concentration. Highly aligned states with orientation distribution coefficients close to unity were obtained at fields as small as 0.2 T. This remarkable field response originates in an enhancement of alignment kinetics due to a reduction in viscosity, and increased magnetostatic energy due to increases in grain size, in the presence of labile mesogens. These developments provide routes for controlling structural order in BCPs, including the possibility of producing nontrivial textures and patterns of alignment by locally screening fields using magnetic nanoparticles. PMID:29078379

High-harmonic spectroscopy of oriented OCS molecules: emission of even and odd harmonics.

PubMed

Kraus, P M; Rupenyan, A; Wörner, H J

2012-12-07

We study the emission of even and odd high-harmonic orders from oriented OCS molecules. We use an intense, nonresonant femtosecond laser pulse superimposed with its phase-controlled second harmonic field to impulsively align and orient a dense sample of molecules from which we subsequently generate high-order harmonics. The even harmonics appear around the full revivals of the rotational dynamics. We demonstrate perfect coherent control over their intensity through the subcycle delay of the two-color fields. The odd harmonics are insensitive to the degree of orientation, but modulate with the degree of axis alignment, in agreement with calculated photorecombination dipole moments. We further compare the shape of the even and odd harmonic spectra with our calculations and determine the degree of orientation.

Orientation observed by Zeeman spectra of dissociated atoms and the interference in photoexcitations

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

Kimura, Yasuyuki; Kasahara, Shunji; Kato, Hajime

2003-06-01

In a magnetic field, the wave number of a pump laser light polarized along the field was fixed to the isolated Cs{sub 2}D {sup 1}{sigma}{sub u}{sup +}(v=46, J=54)(leftarrow)X {sup 1}{sigma}{sub g}{sup +}(v=0, J=55) line, and the excitation spectrum of the dissociated Cs(6p {sup 2}P{sub 3/2}) atoms was measured by scanning the wave number of a probe laser light polarized perpendicular to the field. The population of each sublevel 6p {sup 2}P{sub 3/2,m{sub j}} of the dissociated atoms was determined from the line intensities in the m{sub j}-resolved excitation spectrum. The unequal population between the 6p {sup 2}P{sub 3/2,+verticalbarm{sub j}}{sub verticalbar}more » and 6p {sup 2}P{sub 3/2,-verticalbarm{sub j}}{sub verticalbar} levels (atomic orientation) was observed and it was enhanced as the magnetic-field strength was increased. The atomic orientation is shown to be induced by the interference between the indirect predissociation, which occurs by a combination of the spin-orbit coupling of the D {sup 1}{sigma}{sub u}{sup +} state with the (2){sup 3}{pi}{sub 0u} state and the L-uncoupling and Zeeman interactions between the (2){sup 3}{pi}{sub 0u} and dissociative (2){sup 3}{sigma}{sub u}{sup +} states, and the dissociation following a direct excitation to the (2){sup 3}{sigma}{sub u}{sup +} state, which is allowed by spin-orbit coupling of the (2){sup 3}{sigma}{sub u}{sup +} state with the B {sup 1}{pi}{sub u} state. It is demonstrated that the atomic orientation is produced by the photodissociation in the presence of an external magnetic field even when all degenerated molecular M=J,...,0,...,-J sublevels are excited by a light polarized linearly along the field.« less

Why we cannot conclude that sexual orientation is primarily a biological phenomenon.

PubMed

Byne, W

1997-01-01

While all mental phenomena must have an ultimate biological substrate, the precise contribution of biological factors to the development of sexual orientation remains to be elucidated. Does biology merely provide the slate of neural circuitry upon which sexual orientation is inscribed by experience? Do biological factors directly wire the brain so that it will support a particular orientation? Or do biological factors influence sexual orientation only indirectly, perhaps by influencing personality variables that in turn influence how one interacts with and shapes the environment as it contributes to the social relationships and experiences that shape sexual orientation as it emerges developmentally? Recent neurostructural and genetic linkage evidence pertaining to sexual orientation must be viewed tentatively until it has been adequately corroborated and integrated with psychological and cultural models. Moreover, even a reliable and robust correlation between a biological marker and sexual orientation would be equally compatible with the second and third possibilities delineated above. Yet if the third possibility more closely approximates reality, the search for predisposing biological factors will result in incomplete and misleading findings until their interactions with environmental factors are taken into account and controlled for in adequate longitudinal studies.

Motivational and social cognitive predictors of doping intentions in elite sports: an integrated approach.

PubMed

Barkoukis, V; Lazuras, L; Tsorbatzoudis, H; Rodafinos, A

2013-10-01

Doping use is an important issue in both competitive and non-competitive sports, and poses potentially irreversible health consequences to users. Scholars increasingly call for theory-driven studies on the psychosocial processes underlying doping use that will inform subsequent policy-making and prevention interventions. The aim of the study was to implement an integrative theoretical model to assess the direct and indirect effects of motivational variables, moral orientations, and social cognitions on doping intentions. A randomly selected and representative sample of 750 elite athletes anonymously completed a battery of questionnaires on motivational and moral constructs, and social cognitions related to doping. Hierarchical linear regression analysis and multiple mediation modeling were used. The effects of achievement goals and moral orientations were significantly mediated by attitudinal, normative, and self-efficacy beliefs, in both lifetime ever and never doping users. Moral orientations indirectly predicted the doping intentions of never users, but did not predict ever users' doping intentions. Achievement goals and sportspersonship orientations influence doping intentions indirectly, through the effects of attitudes and self-efficacy beliefs. Sportspersonship (moral) orientations were relevant to doping intentions among athletes with no prior experiences with doping, while achievement goals and situational temptation were relevant to both lifetime never and ever dopers. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The association between reality-based beliefs and indirectly experienced traumatization.

PubMed

Shiri, Shimon; Wexler, Isaiah D; Schwartz, Isabella; Kadari, Michal; Kreitler, Shulamith

2010-12-01

The purpose of the study was to examine the association between belief types and the magnitude of indirect traumatization. Specific types of beliefs were defined in terms of the cognitive orientation theory, which is a cognitive-motivational approach to the understanding, predicting, and changing of behaviors. Belief types that were analyzed included beliefs about self, general beliefs, beliefs about norms, and goal beliefs as they relate to personal growth. Study participants included 38 rescuers (body handlers), 37 nurses, and 31 rehabilitation workers who treated injured civilians that had been exposed to politically motivated violence. The Cognitive Orientation for Posttraumatic Growth Scale was used to assess beliefs about personal growth. The Revised Posttraumatic Stress Disorder Inventory was administered to evaluate indirect traumatization. The results indicate that three of the four belief types related to personal growth were associated with the level of indirect traumatization. Optimistic and positive beliefs about self and general beliefs were associated with a lower level of indirect traumatization symptomatology, suggesting that these types of beliefs may counteract indirect traumatization. On the other hand, stronger goal beliefs were associated with greater indirect traumatization. The negative association between positive goal beliefs and indirect trauma may be related to the gap the individual perceives between the hoped-for ideals and the trauma-stricken reality. These results indicate the importance of cognitive beliefs and their possible role in determining the response to indirect traumatization.

Glyphosate toxicity and the effects of long-term vegetation control on soil microbial communities

Treesearch

Matt D. Busse; Alice W. Ratcliff; Carol J. Stestak; Robert F. Powers

2001-01-01

We assessed the direct and indirect effect of the herbicide glyphosate on soil microbial communities from soil bioassays at glyphosate concentrations up to 100-fold greater than expected following a single field application. Indirect effects on microbial biomass, respiration, and metabolic diversity (Biolog and catabolic response profile) were compared seasonally after...

Training Older Workers: Resource-Oriented Strategies

ERIC Educational Resources Information Center

Jeske, Debora; Stamov Roßnagel, Christian; Strack, Juliane

2017-01-01

The goal of this paper is to outline resource-oriented strategies which may help practitioners provide training that caters for the needs of older workers. Building on resource-oriented frameworks, we review research that directly or indirectly examines the relationship between age and training performance. We identify three personal and three…

Magnetoreception and its trigeminal mediation in the homing pigeon

NASA Astrophysics Data System (ADS)

Mora, Cordula V.; Davison, Michael; Martin Wild, J.; Walker, Michael M.

2004-11-01

Two conflicting hypotheses compete to explain how a homing pigeon can return to its loft over great distances. One proposes the use of atmospheric odours and the other the Earth's magnetic field in the `map' step of the `map and compass' hypothesis of pigeon homing. Although magnetic effects on pigeon orientation provide indirect evidence for a magnetic `map', numerous conditioning experiments have failed to demonstrate reproducible responses to magnetic fields by pigeons. This has led to suggestions that homing pigeons and other birds have no useful sensitivity to the Earth's magnetic field. Here we demonstrate that homing pigeons (Columba livia) can discriminate between the presence and absence of a magnetic anomaly in a conditioned choice experiment. This discrimination is impaired by attachment of a magnet to the cere, local anaesthesia of the upper beak area, and bilateral section of the ophthalmic branch of the trigeminal nerve, but not of the olfactory nerve. These results suggest that magnetoreception (probably magnetite-based) occurs in the upper beak area of the pigeon. Traditional methods of rendering pigeons anosmic might therefore cause simultaneous impairment of magnetoreception so that future orientation experiments will require independent evaluation of the pigeon's magnetic and olfactory systems.

Magnetoreception and its trigeminal mediation in the homing pigeon.

PubMed

Mora, Cordula V; Davison, Michael; Wild, J Martin; Walker, Michael M

2004-11-25

Two conflicting hypotheses compete to explain how a homing pigeon can return to its loft over great distances. One proposes the use of atmospheric odours and the other the Earth's magnetic field in the 'map' step of the 'map and compass' hypothesis of pigeon homing. Although magnetic effects on pigeon orientation provide indirect evidence for a magnetic 'map', numerous conditioning experiments have failed to demonstrate reproducible responses to magnetic fields by pigeons. This has led to suggestions that homing pigeons and other birds have no useful sensitivity to the Earth's magnetic field. Here we demonstrate that homing pigeons (Columba livia) can discriminate between the presence and absence of a magnetic anomaly in a conditioned choice experiment. This discrimination is impaired by attachment of a magnet to the cere, local anaesthesia of the upper beak area, and bilateral section of the ophthalmic branch of the trigeminal nerve, but not of the olfactory nerve. These results suggest that magnetoreception (probably magnetite-based) occurs in the upper beak area of the pigeon. Traditional methods of rendering pigeons anosmic might therefore cause simultaneous impairment of magnetoreception so that future orientation experiments will require independent evaluation of the pigeon's magnetic and olfactory systems.

Plasma-electric field controlled growth of oriented graphene for energy storage applications

NASA Astrophysics Data System (ADS)

Ghosh, Subrata; Polaki, S. R.; Kamruddin, M.; Jeong, Sang Mun; (Ken Ostrikov, Kostya

2018-04-01

It is well known that graphene grows as flat sheets aligned with the growth substrate. Oriented graphene structures typically normal to the substrate have recently attracted major attention. Most often, the normal orientation is achieved in a plasma-assisted growth and is believed to be due to the plasma-induced in-built electric field, which is usually oriented normal to the substrate. This work focuses on the effect of an in-built electric field on the growth direction, morphology, interconnectedness, structural properties and also the supercapacitor performance of various configurations of graphene structures and reveals the unique dependence of these features on the electric field orientation. It is shown that tilting of growth substrates from parallel to the normal direction with respect to the direction of in-built plasma electric field leads to the morphological transitions from horizontal graphene layers, to oriented individual graphene sheets and then interconnected 3D networks of oriented graphene sheets. The revealed transition of the growth orientation leads to a change in structural properties, wetting nature, types of defect in graphitic structures and also affects their charge storage capacity when used as supercapacitor electrodes. This simple and versatile approach opens new opportunities for the production of potentially large batches of differently oriented and structured graphene sheets in one production run.

Dynamic separation of nanomagnet sublattices by orientation of elliptical elements

NASA Astrophysics Data System (ADS)

Yahagi, Y.; Berk, C. R.; Harteneck, B. D.; Cabrini, S. D.; Schmidt, H.

2014-04-01

We report the separation of the magnetization dynamics of densely packed nanomagnets depending on their orientation. The arrays consist of interleaved sublattices of identical nickel elliptical disks. By controlling the orientation of the elliptic disks relative to the external field in each sublattice, we simultaneously analyzed the magnetization dynamics in each sublattice using a time-resolved magnetooptic Kerr effect (TR-MOKE) microscopy system. The Fourier spectra showed clearly separated precession modes for sublattices with different orientations. The spectra were shown to be robust against the error in applied field orientation. The sublattice response can be tuned to a single collective frequency by choosing a symmetric field orientation. We analyzed the effect of the interelement coupling with various spacing between nanomagnets and found a relatively weak dependence on dipolar interactions in good agreement with micromagnetic simulations.

From goal motivation to goal progress: the mediating role of coping in the Self-Concordance Model.

PubMed

Gaudreau, Patrick; Carraro, Natasha; Miranda, Dave

2012-01-01

The present studies examined the mediating role of self-regulatory mechanisms in the relationship between goal motivation and goal progress in the Self-Concordance Model. First, a systematic review, using meta-analytical path analysis, supported the mediating role of effort and action planning in the positive association between autonomous goal motivation and goal progress. Second, results from two additional empirical studies, using structural equation modeling, lent credence to the mediating role of coping in the relationship between goal motivation and goal progress of university students. Autonomous goal motivation was positively associated with task-oriented coping, which predicted greater goal progress during midterm exams (Study 1, N=702) and at the end of the semester in a different sample (Study 2, N=167). Controlled goal motivation was associated with greater disengagement-oriented coping (Study 1 and Study 2) and lesser use of task-oriented coping (Study 2), which reduced goal progress. These results held up after controlling for perceived stress (Study 2). Our findings highlight the importance of coping in the "inception-to-attainment" goal process because autonomous goal motivation indirectly rather than directly predicts goal progress of university students through their usage of task-oriented coping.

Stimuli-Driven Control of the Helical Axis of Self-Organized Soft Helical Superstructures.

PubMed

Bisoyi, Hari Krishna; Bunning, Timothy J; Li, Quan

2018-06-01

Supramolecular and macromolecular functional helical superstructures are ubiquitous in nature and display an impressive catalog of intriguing and elegant properties and performances. In materials science, self-organized soft helical superstructures, i.e., cholesteric liquid crystals (CLCs), serve as model systems toward the understanding of morphology- and orientation-dependent properties of supramolecular dynamic helical architectures and their potential for technological applications. Moreover, most of the fascinating device applications of CLCs are primarily determined by different orientations of the helical axis. Here, the control of the helical axis orientation of CLCs and its dynamic switching in two and three dimensions using different external stimuli are summarized. Electric-field-, magnetic-field-, and light-irradiation-driven orientation control and reorientation of the helical axis of CLCs are described and highlighted. Different techniques and strategies developed to achieve a uniform lying helix structure are explored. Helical axis control in recently developed heliconical cholesteric systems is examined. The control of the helical axis orientation in spherical geometries such as microdroplets and microshells fabricated from these enticing photonic fluids is also explored. Future challenges and opportunities in this exciting area involving anisotropic chiral liquids are then discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Robust generation of Fourier-synthesized laser fields and their estimation of the optical phase by using quantum control of molecular tunneling ionization

NASA Astrophysics Data System (ADS)

Yoshida, Tsuyoshi; Saito, Naoaki; Ohmura, Hideki

2018-03-01

Intense (5.0 × 1012 W cm-2) nanosecond Fourier-synthesized laser fields consisting of fundamental, second-, third-, and fourth-harmonic light generated by an interferometer-free Fourier-synthesized laser field generator induce orientation-selective ionization based on directionally asymmetric molecular tunneling ionization (TI). The laser field generator ensures adjustment-free operation, high stability, and high reproducibility. Phase-sensitive, orientation-selective molecular TI provides a simple way to estimate the relative phase differences between the fundamental light and each harmonic by data-fitting analysis. This application of Fourier-synthesized laser fields will facilitate not only lightwave engineering but also the control of matter.

Carrier-envelope phase-dependent field-free molecular orientation

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

Shu Chuancun; Yuan Kaijun; Hu Wenhui

2009-07-15

We present a strategy to achieve carrier-envelope phase-dependent field-free molecular orientation with the use of carrier-envelope phase (CEP) stabilization and asymmetric few-cycle terahertz (THz) laser pulses. The calculations are performed on the LiH molecule by an exact solution of the full time-dependent Schroedinger equation including both the vibrational and the rotational degrees of freedom. Our calculations show that an efficient field-free molecular orientation can be obtained even at considerable temperatures. Moreover, we find a simple dependence of the field-free orientation on the CEP, which implies that the CEP becomes an important parameter for control of molecular orientation. More importantly, themore » realization of this scenario is appealing based on the fact that the intense few-cycle THz pulse with duration as short as a few optical cycles is available as a research tool.« less

Orientational control of block copolymer microdomains by sub-tesla magnetic fields

NASA Astrophysics Data System (ADS)

Gopinadhan, Manesh; Choo, Youngwoo; Feng, Xunda; Kawabata, Kohsuke; di, Xiaojun; Osuji, Chinedum

Magnetic fields offer a versatile approach to controlling the orientation of block copolymer (BCP) microdomains during self-assembly. To date however, such control has required the imposition of large magnetic fields (>3T), necessitating the use of complex magnet systems - either superconducting or very large conventional resistive magnets. Here we demonstrate the ability to direct BCP self-assembly using considerably smaller fields (<1T) which are accessible using simple rare-earth permanent magnets. The low field alignment is enabled by the presence of small quantities of mesogenic species that are blended into, and co-assemble with the liquid crystalline (LC) mesophase of the side-chain LC BCP under study. In situ SAXS experiments reveal a pronounced dependence of the critical alignment field strength on the stoichiometry of the blend, and the ability to generate aligned microdomains with orientational distribution coefficients exceeding 0.95 at sub-1 T fields for appropriate stoichiometries. The alignment response overall can be rationalized in terms of increased mobility and grain size due to the presence of the mesogenic additive. We use a permanent magnet to fabricate films with aligned nanopores, and the utility of this approach to generate complex BCP microdomain patterns in thin films by local field screening are highlighted. NSF DMR-1410568 and DMR-0847534.

Investigation of possible causes for human-performance degradation during microgravity flight

NASA Technical Reports Server (NTRS)

Schroeder, James E.; Tuttle, Megan L.

1992-01-01

The results of the first year of a three year study of the effects of microgravity on human performance are given. Test results show support for the hypothesis that the effects of microgravity can be studied indirectly on Earth by measuring performance in an altered gravitational field. The hypothesis was that an altered gravitational field could disrupt performance on previously automated behaviors if gravity was a critical part of the stimulus complex controlling those behaviors. In addition, it was proposed that performance on secondary cognitive tasks would also degrade, especially if the subject was provided feedback about degradation on the previously automated task. In the initial experimental test of these hypotheses, there was little statistical support. However, when subjects were categorized as high or low in automated behavior, results for the former group supported the hypotheses. The predicted interaction between body orientation and level of workload in their joint effect on performance in the secondary cognitive task was significant for the group high in automatized behavior and receiving feedback, but no such interventions were found for the group high in automatized behavior but not receiving feedback, or the group low in automatized behavior.

Parent-Child Cultural Orientations and Child Adjustment in Chinese American Immigrant Families

ERIC Educational Resources Information Center

Chen, Stephen H.; Hua, Michelle; Zhou, Qing; Tao, Annie; Lee, Erica H.; Ly, Jennifer; Main, Alexandra

2014-01-01

Direct and indirect/mediated relations of (a) children's and parents' cultural orientations and (b) parent-child gaps in cultural orientations to children's psychological adjustment were examined in a socioeconomically diverse sample of 258 Chinese American children (age = 6-9 years) from immigrant families. Parents reported on children's and…

Visual direction finding by fishes

NASA Technical Reports Server (NTRS)

Waterman, T. H.

1972-01-01

The use of visual orientation, in the absence of landmarks, for underwater direction finding exercises by fishes is reviewed. Celestial directional clues observed directly near the water surface or indirectly at an asymptatic depth are suggested as possible orientation aids.

Future orientation and competence to stand trial: the fragility of competence.

PubMed

Kivisto, Aaron J; Moore, Todd M; Fite, Paula A; Seidner, Bruce G

2011-01-01

The current study examined the direct, indirect, and interactive effects of age, intellectual ability, psychiatric symptomatology, and future orientation on juvenile adjudicative competence utilizing a secondary sample of 927 youth from the MacArthur Juvenile Adjudicative Competence Study. Consistent with previous research, age, intellectual ability, and future orientation were found to be positively associated with competence, and psychiatric symptomatology was weakly negatively related to competence. Tests of indirect effects revealed that the development of an orientation toward future consequences partially explains the relationship between age and the capacity to reason about legal decision-making. Further, tests of invariance revealed that the competence of immature adolescents is particularly "fragile," in that smaller deficits in cognitive abilities appear to pose greater problems in youths regarding their adjudicative competence than in their more mature peers. Findings are discussed in regard to forensic practice as well as for future research.

Measuring implicit gender-role orientation: the gender initial preference task.

PubMed

Stieger, Stefan; Burger, Christoph; Schiller, Franziska R; Schulze, Esther K; Voracek, Martin

2014-01-01

Individuals prefer their name letters over nonname letters, which is known as the name-letter effect (NLE). This research aimed to examine a possible NLE for gender-role orientation (GRO) by rating letters for their gender-typicality in an initial preference task (Gender-IPT). Indeed, a clear NLE appeared: Men rated their initials as more male-typical, whereas women rated them as more female-typical. The Gender-IPT showed good convergent validity with other direct and indirect (Gender Implicit Association Test) measures of GRO as well as predictive validity with sensation seeking and gender-typical everyday life behaviors. The Gender-IPT seems to be a useful and practical indirect measure to assess GRO in a short, convenient, and computer-independent way, complementing other indirect measures of GRO.

Stability limits for the supercooled liquid and superheated crystal of Lennard-Jones particles

NASA Astrophysics Data System (ADS)

Loscar, Ernesto S.; Martin, Daniel A.; Grigera, Tomás S.

2017-07-01

We have studied the limits of stability in the first order liquid-solid phase transition in a Lennard-Jones system by means of the short-time relaxation method and using the bond-orientational order parameter Q6. These limits are compared with the melting line. We have paid special attention to the supercooled liquid, comparing our results with the point where the free energy cost of forming a nucleating droplet goes to zero. We also indirectly estimate the dimension associated to the critical nucleus at the spinodal, expected to be fractal according to mean field theories of nucleation.

Predictors of race, adoption, and sexual orientation related socialization of adoptive parents of young children.

PubMed

Goldberg, Abbie E; Smith, JuliAnna Z

2016-04-01

Using a sample of 125 lesbian, gay, and heterosexual adoptive parent couples with young children (M = 6.32 years), this study examined predictors of direct socialization (preparation for adoptism, racism, and heterosexism) and indirect socialization (modeling interactions by responding to outsiders' inquiries about their child's adoptive status, racial background, or family structure). In terms of direct socialization, parents of older children tended to engage in more socialization around adoptism and heterosexism, and parents of daughters tended to engage in more socialization around racism and heterosexism. Greater perceived child interest in adoption was related to more direct socialization around adoptism. Parents of color reported more direct socialization around racism. Having a child of color was related to more direct socialization around heterosexism. Regarding indirect socialization, sexual minority parents reported more socialization around adoption and race. Greater perceived child interest in adoption was related to more indirect adoption socialization. Being more "out" was related to more indirect socialization around parent sexual orientation. (c) 2016 APA, all rights reserved).

Tunable inversion symmetry to control indirect-to-direct band gaps transitions

NASA Astrophysics Data System (ADS)

Lu, Xue-Zeng; Rondinelli, James M.

2018-05-01

Electric-field tunable indirect-to-direct band gap transitions occur in thin-film silicon and transition metal dichalcogenides; however, they remain challenging to access in three-dimensional transition metal oxides. Very recently, an unusual polar-to-nonpolar phase transition under epitaxial strain was discovered in A3B2O7 hybrid improper ferroelectrics (HIFs), which supports controllable dielectric anisotropy and magnetization. Here we examine HIF (ABO3) 1/(A'BO3) 1 superlattices and AA'BB' O6 double perovskites and predict a competing nonpolar antiferroelectric phase, demonstrating it is hidden in hybrid improper ferroelectrics exhibiting corner-connected B O6 octahedra. Furthermore, we show the transition between the polar and nonpolar phases enables an in-plane electric field to control the indirect-to-direct band gap transition at the phase boundary in the (ABO3) 1/(A'BO3) 1 superlattices and AA'BB' O6 double perovskites, which may be tuned through static strain or chemical substitution. Our findings establish HIFs as a functional electronics class from which to realize direct gap materials and enables the integration of a broader palette of chemistries and compounds for linear and nonlinear optical applications.

Lesbian, gay, & bisexual older adults: linking internal minority stressors, chronic health conditions, and depression.

PubMed

Hoy-Ellis, Charles P; Fredriksen-Goldsen, Karen I

2016-11-01

This study aims to: (1) test whether the minority stressors disclosure of sexual orientation; and (2) internalized heterosexism are predictive of chronic physical health conditions; and (3) depression; (4) to test direct and indirect relationships between these variables; and (5) whether chronic physical health conditions are further predictive of depression, net of disclosure of sexual orientation and internalized heterosexism. Secondary analysis of national, community-based surveys of 2349 lesbian, gay, and bisexual adults aged 50 and older residing in the US utilizing structural equation modeling. Congruent with minority stress theory, disclosure of sexual orientation is indirectly associated with chronic physical health conditions and depression, mediated by internalized heterosexism with a suppressor effect. Internalized heterosexism is directly associated with chronic physical health conditions and depression, and further indirectly associated with depression mediated by chronic physical health conditions. Finally, chronic physical health conditions have an additional direct relationship with depression, net of other predictor variables. Minority stressors and chronic physical health conditions independently and collectively predict depression, possibly a synergistic effect. Implications for depression among older sexual minority adults are discussed.

Avuncular tendencies and the evolution of male androphilia in Samoan fa'afafine.

PubMed

Vasey, Paul L; VanderLaan, Doug P

2010-08-01

The kin selection hypothesis for male androphilia holds that genes for male androphilia can be maintained in a population if the fitness costs of not reproducing directly are offset by enhancing indirect fitness. Kin share some proportion of genes identical by virtue of descent. Theoretically speaking, androphilic males can increase their fitness indirectly by allocating altruistic behavior toward kin, which, in turn, allows kin to increase their reproductive success. Research conducted in Independent Samoa has shown that androphilic males (known locally as fa'afafine) report significantly higher avuncular tendencies relative to gynephilic men. Here, we replicate this sexual orientation difference, using a larger, independent sample, suggesting that the documented sexual orientation difference in avuncular tendencies in Independent Samoa is genuine. We also extend previous research by showing that fa'afafine exhibit significantly higher avuncular tendencies even when compared to a more closely matched control group that also lacks direct parental care responsibilities (i.e., gynephilic men with no children). Although the greater avuncular tendencies of fa'afafine relative to gynephilic men are consistent with the predictions of the kin selection hypothesis for male androphilia, further research is needed before deeming male androphilia an adaptation for promoting elevated avuncularity. Likewise, more research is needed before deeming elevated avuncularity in fa'afafine an evolved adaptation for promoting indirect fitness. We discuss these findings in the context of alternative evolutionary explanations for male androphilia (i.e., an evolved by-product of an adaptation).

Domain and phase change contributions to response in high strain piezoelectric actuators

NASA Astrophysics Data System (ADS)

Cross, L. Eric

2000-09-01

Current solid state actuators are briefly compared to traditional actuator technologies to highlight the major need for enhanced strain capability. For the ferroelectric piezoelectric polycrystal ceramics, the balance of evidence suggests a large entrinsic contribution to the field induced strain from ferroelectric-ferroelastic domain wall motion. Here-to-fore the intrinsic single domain contribution has been derived indirectly from phenomenological analysis. Now, new evidence of a stable monoclinic phase at compositions very close to the MPB suggest that the previous assessment will need to be revised. Actuator behavior in the new lead zinc niobate-lead titanate (PZN:PT) single crystal shows most unusual anisotropic behavior. For 111 oriented field poled crystals in the rhombohedral phase normal low induced strain is observed. For 001 field poled crystals however massive (0.6%) quasi-linear anhysteritic strain can be induced. Since the 001 oriented field in the rhombohedral phase can not drive ferroelastic domain walls it is suggested that the strain must be intrinsic. The suggestion is that it is due to an induced monoclinic phase in which the Ps vector tilts under increasing field up to more than 20° from 111, before the vector switches to the tetragonal 001 direction. Such a polarization rotation mechanism has also been suggested by Fu and Cohen. Calculations of induced single domain strain using measured electrostriction constants agree well with observed behavior. Recent measurements by Park et al. and Wada et al. on single crystal BaTiO3 show strongly enhanced piezoelectricity at temperatures near the ferroelectric phase transitions. Of particular relevance is the inverse experiment forcing the tetragonal over to the rhombohedral phase with high 111 oriented field. From this result it is suggested that both cubic and dodecahedral mirrors participate in the reorientation through orthorhombic to the rhombohedral state giving rise to different value of the induced d33 at different field levels.

Orientation selective deep brain stimulation

NASA Astrophysics Data System (ADS)

Lehto, Lauri J.; Slopsema, Julia P.; Johnson, Matthew D.; Shatillo, Artem; Teplitzky, Benjamin A.; Utecht, Lynn; Adriany, Gregor; Mangia, Silvia; Sierra, Alejandra; Low, Walter C.; Gröhn, Olli; Michaeli, Shalom

2017-02-01

Objective. Target selectivity of deep brain stimulation (DBS) therapy is critical, as the precise locus and pattern of the stimulation dictates the degree to which desired treatment responses are achieved and adverse side effects are avoided. There is a clear clinical need to improve DBS technology beyond currently available stimulation steering and shaping approaches. We introduce orientation selective neural stimulation as a concept to increase the specificity of target selection in DBS. Approach. This concept, which involves orienting the electric field along an axonal pathway, was tested in the corpus callosum of the rat brain by freely controlling the direction of the electric field on a plane using a three-electrode bundle, and monitoring the response of the neurons using functional magnetic resonance imaging (fMRI). Computational models were developed to further analyze axonal excitability for varied electric field orientation. Main results. Our results demonstrated that the strongest fMRI response was observed when the electric field was oriented parallel to the axons, while almost no response was detected with the perpendicular orientation of the electric field relative to the primary fiber tract. These results were confirmed by computational models of the experimental paradigm quantifying the activation of radially distributed axons while varying the primary direction of the electric field. Significance. The described strategies identify a new course for selective neuromodulation paradigms in DBS based on axonal fiber orientation.

Gate control of quantum dot-based electron spin-orbit qubits

NASA Astrophysics Data System (ADS)

Wu, Shudong; Cheng, Liwen; Yu, Huaguang; Wang, Qiang

2018-07-01

We investigate theoretically the coherent spin dynamics of gate control of quantum dot-based electron spin-orbit qubits subjected to a tilted magnetic field under electric-dipole spin resonance (EDSR). Our results reveal that Rabi oscillation of qubit states can be manipulated electrically based on rapid gate control of SOC strength. The Rabi frequency is strongly dependent on the gate-induced electric field, the strength and orientation of the applied magnetic field. There are two major EDSR mechanisms. One arises from electric field-induced spin-orbit hybridization, and the other arises from magnetic field-induced energy-level crossing. The SOC introduced by the gate-induced electric field allows AC electric fields to drive coherent Rabi oscillations between spin-up and -down states. After the crossing of the energy-levels with the magnetic field, the spin-transfer crossing results in Rabi oscillation irrespective of whether or not the external electric field is present. The spin-orbit qubit is transferred into the orbit qubit. Rabi oscillation is anisotropic and periodic with respect to the tilted and in-plane orientation of the magnetic field originating from the interplay of the SOC, orbital, and Zeeman effects. The strong electrically-controlled SOC strength suggests the possibility for scalable applications of gate-controllable spin-orbit qubits.

Control of liquid crystal molecular orientation using ultrasound vibration

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

Taniguchi, Satoki; Wave Electronics Research Center, Doshisha University, 1-3 Tataramiyakodani, Kyotanabe, Kyoto 610-0321; Koyama, Daisuke

2016-03-07

We propose a technique to control the orientation of nematic liquid crystals using ultrasound and investigate the optical characteristics of the oriented samples. An ultrasonic liquid crystal cell with a thickness of 5–25 μm and two ultrasonic lead zirconate titanate transducers was fabricated. By exciting the ultrasonic transducers, the flexural vibration modes were generated on the cell. An acoustic radiation force to the liquid crystal layer was generated, changing the molecular orientation and thus the light transmission. By modulating the ultrasonic driving frequency and voltage, the spatial distribution of the molecular orientation of the liquid crystals could be controlled. The distributionmore » of the transmitted light intensity depends on the thickness of the liquid crystal layer because the acoustic field in the liquid crystal layer is changed by the orientational film.« less

Nanoscale Control over the Mixing Behavior of Surface-Confined Bicomponent Supramolecular Networks Using an Oriented External Electric Field

PubMed Central

2017-01-01

Strong electric fields are known to influence the properties of molecules as well as materials. Here we show that by changing the orientation of an externally applied electric field, one can locally control the mixing behavior of two molecules physisorbed on a solid surface. Whether the starting two-component network evolves into an ordered two-dimensional (2D) cocrystal, yields an amorphous network where the two components phase separate, or shows preferential adsorption of only one component depends on the solution stoichiometry. The experiments are carried out by changing the orientation of the strong electric field that exists between the tip of a scanning tunneling microscope and a solid substrate. The structure of the two-component network typically changes from open porous at negative substrate bias to relatively compact when the polarity of the applied bias is reversed. The electric-field-induced mixing behavior is reversible, and the supramolecular system exhibits excellent stability and good response efficiency. When molecular guests are adsorbed in the porous networks, the field-induced switching behavior was found to be completely different. Plausible reasons behind the field-induced mixing behavior are discussed. PMID:29112378

Dual tuning in creative processes: Joint contributions of intrinsic and extrinsic motivational orientations.

PubMed

Gong, Yaping; Wu, Junfeng; Song, Lynda Jiwen; Zhang, Zhen

2017-05-01

Intrinsic and extrinsic motivational orientations often coexist and can serve important functions. We develop and test a model in which intrinsic and extrinsic motivational orientations interact positively to influence personal creativity goal. Personal creativity goal, in turn, has a positive relationship with incremental creativity and an inverted U-shaped relationship with radical creativity. In a pilot study, we validated the personal creativity goal measure using 180 (Sample 1) and 69 (Sample 2) employees from a consulting firm. In the primary study, we tested the overall model using a sample of 657 research and development employees and their direct supervisors from an automobile firm. The results support the hypothesized model and yield several new insights. Intrinsic and extrinsic motivational orientations synergize with each other to strengthen personal creativity goal. Personal creativity goal in turn benefits incremental and radical creativity, but only up to a certain point for the latter. In addition to its linear indirect relationship with incremental creativity, intrinsic motivational orientation has an inverted U-shaped indirect relationship with radical creativity via personal creativity goal. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Controlling Growth Orientation of Phthalocyanine Films by Electrical Fields

NASA Technical Reports Server (NTRS)

Zhu, S.; Banks, C. E.; Frazier, D. O.; Ila, D.; Muntele, I.; Penn, B. G.; Sharma, A.; Rose, M. Franklin (Technical Monitor)

2001-01-01

Organic Phthalocyanine films have many applications ranging from data storage to various non-linear optical devices whose quality is affected by the growth orientation of Phthalocyanine films. Due to the structural and electrical properties of Phthalocyanine molecules, the film growth orientation depends strongly on the substrate surface states. In this presentation, an electrical field up to 4000 V/cm is introduced during film growth. The Phthalocyanine films are synthesized on quartz substrates using thermal evaporation. An intermediate layer is deposited on some substrates for introducing the electrical field. Scanning electron microscopy, x-ray diffraction, and Fourier transform infrared spectroscopy are used for measuring surface morphology, film structure, and optical properties, respectively. The comparison of Phthalocyanine films grown with and without the electrical field reveals different morphology, film density, and growth orientation, which eventually change optical properties of these films. These results suggest that the growth method in the electrical field can be used to synthesized Phthalocyanine films with a preferred crystal orientation as well as propose an interaction mechanism between the substrate surface and the depositing molecules. The details of growth conditions and of the growth model of how the Phthalocyanine molecules grow in the electrical field will be discussed.

Field-Oriented Control Of Induction Motors

NASA Technical Reports Server (NTRS)

Burrows, Linda M.; Roth, Mary Ellen; Zinger, Don S.

1993-01-01

Field-oriented control system provides for feedback control of torque or speed or both. Developed for use with commercial three-phase, 400-Hz, 208-V, 5-hp motor. Systems include resonant power supply operating at 20 kHz. Pulse-population-modulation subsystem selects individual pulses of 20-kHz single-phase waveform as needed to synthesize three waveforms of appropriate lower frequency applied to three phase windings of motor. Electric actuation systems using technology currently being built to peak powers of 70 kW. Amplitude of voltage of effective machine-frequency waveform determined by momentary frequency of pulses, while machine frequency determined by rate of repetition of overall temporal pattern of pulses. System enables independent control of both voltage and frequency.

Field Tested Service Oriented Robotic Architecture: Case Study

NASA Technical Reports Server (NTRS)

Flueckiger, Lorenzo; Utz, Hanz

2012-01-01

This paper presents the lessons learned from six years of experiments with planetary rover prototypes running the Service Oriented Robotic Architecture (SORA) developed by the Intelligent Robotics Group (IRG) at NASA Ames Research Center. SORA relies on proven software methods and technologies applied to the robotic world. Based on a Service Oriented Architecture and robust middleware, SORA extends its reach beyond the on-board robot controller and supports the full suite of software tools used during mission scenarios from ground control to remote robotic sites. SORA has been field tested in numerous scenarios of robotic lunar and planetary exploration. The results of these high fidelity experiments are illustrated through concrete examples that have shown the benefits of using SORA as well as its limitations.

Considering direct and indirect habitat influences on stream biota in eco-geomorphology research to better understand, model, and manage riverine ecosystems

NASA Astrophysics Data System (ADS)

Cienciala, P.; Nelson, A. D.

2017-12-01

The field of fluvial eco-geomorphology strives to improve the understanding of interactions between physical and biological processes in running waters. This body of research has greatly contributed to the advancement of integrated river science and management. Arguably, the most popular research themes in eco-geomorphology include hydrogemorphic controls of habitat quality and effects of disturbances such as floods, sediment transport events or sediment accumulation. However, in contrast to the related field of ecology, the distinction between direct and indirect mechanisms which may affect habitat quality and biotic response to disturbance has been poorly explored in eco-geomorphic research. This knowledge gap poses an important challenge for interpretations of field observations and model development. In this research, using the examples of benthic invertebrates and fish, we examine the importance of direct and indirect influences that geomorphic and hydraulic processes may exert on stream biota. We also investigate their implications for modeling of organism-habitat relationships. To achieve our goal, we integrate field and remote sensing data from montane streams in the Pacific Northwest region with habitat models. Preliminary results indicate that indirect hydrogeomorphic influences of stream organisms, such as those mediated by altered availability of food resources, can be as important as direct influences (e.g. physical disturbance). We suggest that these findings may also have important implications for modeling of riverine habitat.

Measurement of Anisotropic Particle Interactions with Nonuniform ac Electric Fields.

PubMed

Rupp, Bradley; Torres-Díaz, Isaac; Hua, Xiaoqing; Bevan, Michael A

2018-02-20

Optical microscopy measurements are reported for single anisotropic polymer particles interacting with nonuniform ac electric fields. The present study is limited to conditions where gravity confines particles with their long axis parallel to the substrate such that particles can be treated using quasi-2D analysis. Field parameters are investigated that result in particles residing at either electric field maxima or minima and with long axes oriented either parallel or perpendicular to the electric field direction. By nonintrusively observing thermally sampled positions and orientations at different field frequencies and amplitudes, a Boltzmann inversion of the time-averaged probability of states yields kT-scale energy landscapes (including dipole-field, particle-substrate, and gravitational potentials). The measured energy landscapes show agreement with theoretical potentials using particle conductivity as the sole adjustable material property. Understanding anisotropic particle-field energy landscapes vs field parameters enables quantitative control of local forces and torques on single anisotropic particles to manipulate their position and orientation within nonuniform fields.

Race-Ethnicity and Culture in the Family and Youth Outcomes: Test of a Path Model with Korean American Youth and Parents

PubMed Central

Choi, Yoonsun; Tan, Kevin Poh Hiong; Yasui, Miwa; Pekelnicky, Dina Drankus

2014-01-01

This study examined the interplay of parental racial-ethnic socialization and youth multidimensional cultural orientations to investigate how they indirectly and directly influence youth depressive symptoms and antisocial behaviors. Using data from the Korean American Families (KAF) Project (220 youths, 272 mothers, and 164 fathers, N = 656), this study tested the relationships concurrently, longitudinally, and accounting for earlier youth outcomes. The main findings include that racial-ethnic socialization is significantly associated with mainstream and ethnic cultural orientation among youth, which in turn influences depressive symptoms (but not antisocial behaviors). More specifically, parental racial-ethnic identity and pride discourage youth mainstream orientation, whereas cultural socialization in the family, as perceived by youth, increases ethnic orientation. These findings suggest a varying impact of racial-ethnic socialization on the multidimensional cultural orientations of youth. Korean language proficiency of youth was most notably predictive of a decrease in the number of depressive symptoms concurrently, longitudinally, and after controlling for previous levels of depressive symptoms. English language proficiency was also associated with a decrease in depressive symptoms, implying a benefit of bilingualism. PMID:24611081

Control of Rydberg atom blockade by dc electric field orientation in a quasi-one-dimensional sample

NASA Astrophysics Data System (ADS)

Goncalves, Luís Felipe; Marcassa, Luis Gustavo

2017-04-01

Rydberg atoms posse a strong atom-atom interaction, which limits its density in an atomic sample. Such effect is known as Rydberg atom blockade. Here, we present a novel way to control such effect by direct orienting the induced atomic dipole moment using a dc external electrical field. To demonstrate it, we excite the 50S1 / 2 Rb atomic state in a quasi-one-dimensional sample held in a quasi-electrostatic trap. A pure nS state holds only van der Waals interaction at long range, but in the presence of an external electric field the state mixing leads to strong dipole-dipole interactions. We have measured the Rydberg atom population as a function of ground state atoms density for several angles between the electric field and the main axis of the unidimensional sample. The results indicate that the limit on the final Rydberg density can be controlled by electric field orientation. Besides, we have characterized the sample by using direct spatial ion imaging, demonstrating that it does behave as an unidimensional sample. This work was supported by Sao Paulo Research Foundation (FAPESP) Grants No. 2011/22309-8 and No. 2013/02816- 8, the U.S. Army Research Office Grant No. W911NF-15-1-0638 and CNPq.

Better understanding work unit goal orientation: Its emergence and impact under different types of work unit structure.

PubMed

Dragoni, Lisa; Kuenzi, Maribeth

2012-09-01

With a multisource sample comprising 1,150 employees and 230 supervisors, we investigate the effect of leader goal orientation on leader's perceptions of unit performance. We propose that a leader's goal orientation indirectly impacts performance perceptions via the shared achievement goal adopted within the unit (i.e., unit goal orientation). Further, we hypothesize that the presence and impact of unit goal orientation depend on the work unit structure. We find general support for this moderated mediation model, with the strongest evidence being associated with the learning and prove dimensions of goal orientation.

Field gradients can control the alignment of nanorods.

PubMed

Ooi, Chinchun; Yellen, Benjamin B

2008-08-19

This work is motivated by the unexpected experimental observation that field gradients can control the alignment of nonmagnetic nanorods immersed inside magnetic fluids. In the presence of local field gradients, nanorods were observed to align perpendicular to the external field at low field strengths, but parallel to the external field at high field strengths. The switching behavior results from the competition between a preference to align with the external field (orientational potential energy) and preference to move into regions of minimum magnetic field (positional potential energy). A theoretical model is developed to explain this experimental behavior by investigating the statistics of nanorod alignment as a function of both the external uniform magnetic field strength and the local magnetic field variation above a periodic array of micromagnets. Computational phase diagrams are developed which indicate that the relative population of nanorods in parallel and perpendicular states can be adjusted through several control parameters. However, an energy barrier to rotation was discovered to influence the rate kinetics and restrict the utility of this assembly technique to nanorods which are slightly shorter than the micromagnet length. Experimental results concerning the orientation of nanorods inside magnetic fluid are also presented and shown to be in strong agreement with the theoretical work.

Preservice Students' Attitudes toward Pupil Control as They Develop throughout the Field Experiences.

ERIC Educational Resources Information Center

Killian, Joyce E.; McIntyre, D. John

This study used repeated measures of the Pupil Control Ideology (PCI) instrument to examine the change in student teacher orientation toward pupil control ideology occurring during a three semester field experience. The instrument was given to elementary and secondary education majors at Southern Illinois University at Carbondale five different…

Self-regulation: from goal orientation to job performance.

PubMed

Porath, Christine L; Bateman, Thomas S

2006-01-01

The authors investigated the effects on job performance of 3 forms of goal orientation and 4 self-regulation (SR) tactics. In a longitudinal field study with salespeople, learning and performance-prove goal orientation predicted subsequent sales performance, whereas performance-avoid goal orientation negatively predicted sales performance. The SR tactics functioned as mediating variables between learning and performance-prove goal orientations and performance. Social competence and proactive behavior directly and positively predicted sales performance, and emotional control negatively predicted performance. (c) 2006 APA, all rights reserved.

Highly Polarized Fluorescent Illumination Using Liquid Crystal Phase.

PubMed

Gim, Min-Jun; Turlapati, Srikanth; Debnath, Somen; Rao, Nandiraju V S; Yoon, Dong Ki

2016-02-10

Liquid crystal (LC) materials are currently the dominant electronic materials in display technology because of the ease of control of molecular orientation using an electric field. However, this technology requires the fabrication of two polarizers to create operational displays, reducing light transmission efficiency below 10%. It is therefore desirable to develop new technologies to enhance the light efficiency while maintaining or improving other properties such as the modulation speed of the molecular orientation. Here we report a uniaxial-oriented B7 smectic liquid crystalline film, using fluorescent bent-core LC molecules, a chemically modified substrate, and an in-plane electric field. A LC droplet under homeotropic boundary conditions of air/LC as well as LC/substrate exhibits large focal conic like optical textures. The in-plane electric field induced uniaxial orientation of the LC molecules, in which molecular polar directors are aligned in the direction of the electric field. This highly oriented LC film exhibits linearly polarized luminescence and microsecond time-scale modulation characteristics. The resultant device is both cheap and easy to fabricate and thus has great potential for electro-optic applications, including LC displays, bioimaging systems, and optical communications.

Effects of orientation on the time decay of magnetization for cobalt-alloy thin film media

NASA Astrophysics Data System (ADS)

Wang, J. P.; Alex, Michael; Tan, L. P.; Yan, M. L.

1999-04-01

The dependence of the time decay of magnetization on orientation ratio was investigated for longitudinal Co-alloy thin film media. The coercivity orientation ratio was controlled by the degree of mechanical texture. For oriented samples, it was found that the remanent magnetization along the circumferential direction decayed faster with time than that along the radial direction when the applied reverse magnetic field was near the remanent coercivity. However, the remanent magnetization along the circumferential direction decayed more slowly with time than that along the radial direction when the applied reverse magnetic field was less than roughly half the remanent coercivity. Anisotropic interactions and magnetic anisotropy distributions appear to be the cause for the different time decay of magnetization along the circumferential and radial directions for oriented media.

A high-damping magnetorheological elastomer with bi-directional magnetic-control modulus for potential application in seismology

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

Yu, Miao, E-mail: yumiao@cqu.edu.cn; Qi, Song; Fu, Jie

A high-damping magnetorheological elastomer (MRE) with bi-directional magnetic-control modulus is developed. This MRE was synthesized by filling NdFeB particles into polyurethane (PU)/ epoxy (EP) interpenetrating network (IPN) structure. The anisotropic samples were prepared in a permanent magnetic field and magnetized in an electromagnetic field of 1 T. Dynamic mechanical responses of the MRE to applied magnetic fields are investigated through magneto-rheometer, and morphology of MREs is observed via scanning electron microscope (SEM). Test result indicates that when the test field orientation is parallel to that of the sample's magnetization, the shear modulus of sample increases. On the other hand, when themore » orientation is opposite to that of the sample's magnetization, shear modulus decreases. In addition, this PU/EP IPN matrix based MRE has a high-damping property, with high loss factor and can be controlled by applying magnetic field. It is expected that the high damping property and the ability of bi-directional magnetic-control modulus of this MRE offer promising advantages in seismologic application.« less

Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet)

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

None, None

2013-11-01

Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks formore » roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. This project directly investigated rain and indirectly investigated built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.« less

[Psychometric assessment of defense mechanisms: correlation between questionnaire and expert rating. Initial study of validity].

PubMed

Reister, G; Fellhauer, R F; Franz, M; Wirth, T; Schellberg, D; Schepank, H; Tress, W

1993-01-01

Within the limits of an epidemiological longitudinal field survey on prevalence and course of psychogenic disorders a high-risk-population suffering from medical psychogenic impairment was investigated. The study was conducted in order to verify an etiological multi-level-model of psychogenic disorders in relation to the socialempiric variables "critical life events" and "social support" as well as the depth psychological oriented construct "personality". Besides other instruments a self rating scale based on Vallant's hierarchical model of defense, i.e. the german adaptation of the DSQ (Defense Style Questionnaire) of Bond and coworkers, was used for the accurate measurement of relevant personality parameters. Although defense processes predominantly work unconscious, manifestations of defense mechanisms could be measured indirectly by means of the rating scale. Its essential dimensions separated clinical patients from a group of healthy controls. Furthermore an immature organisation of defense was found to be related to psychogenic impairment. Concerning self- and expert-rating a significant correlation between "immature defense" and the defense mechanisms "schizoid phantasy", "projection" and "acting out" was proved.

Lost at sea: ocean acidification undermines larval fish orientation via altered hearing and marine soundscape modification

PubMed Central

Rossi, Tullio; Nagelkerken, Ivan; Connell, Sean D.

2016-01-01

The dispersal of larvae and their settlement to suitable habitat is fundamental to the replenishment of marine populations and the communities in which they live. Sound plays an important role in this process because for larvae of various species, it acts as an orientational cue towards suitable settlement habitat. Because marine sounds are largely of biological origin, they not only carry information about the location of potential habitat, but also information about the quality of habitat. While ocean acidification is known to affect a wide range of marine organisms and processes, its effect on marine soundscapes and its reception by navigating oceanic larvae remains unknown. Here, we show that ocean acidification causes a switch in role of present-day soundscapes from attractor to repellent in the auditory preferences in a temperate larval fish. Using natural CO2 vents as analogues of future ocean conditions, we further reveal that ocean acidification can impact marine soundscapes by profoundly diminishing their biological sound production. An altered soundscape poorer in biological cues indirectly penalizes oceanic larvae at settlement stage because both control and CO2-treated fish larvae showed lack of any response to such future soundscapes. These indirect and direct effects of ocean acidification put at risk the complex processes of larval dispersal and settlement. PMID:26763221

Visual cueing considerations in Nap-of-the-Earth helicopter flight head-slaved helmet-mounted displays

NASA Technical Reports Server (NTRS)

Grunwald, Arthur J.; Kohn, Silvia

1993-01-01

The pilot's ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays, commonly used in Apache and Cobra helicopter night operations, originates from a relatively narrow field-of-view Forward Looking Infrared Radiation Camera, gimbal-mounted at the nose of the aircraft and slaved to the pilot's line-of-sight, in order to obtain a wide-angle field-of-regard. Pilots have encountered considerable difficulties in controlling the aircraft by these devices. Experimental simulator results presented here indicate that part of these difficulties can be attributed to head/camera slaving system phase lags and errors. In the presence of voluntary head rotation, these slaving system imperfections are shown to impair the Control-Oriented Visual Field Information vital in vehicular control, such as the perception of the anticipated flight path or the vehicle yaw rate. Since, in the presence of slaving system imperfections, the pilot will tend to minimize head rotation, the full wide-angle field-of-regard of the line-of-sight slaved Helmet-Mounted Display, is not always fully utilized.

Rotating magnetizations in electrical machines: Measurements and modeling

NASA Astrophysics Data System (ADS)

Thul, Andreas; Steentjes, Simon; Schauerte, Benedikt; Klimczyk, Piotr; Denke, Patrick; Hameyer, Kay

2018-05-01

This paper studies the magnetization process in electrical steel sheets for rotational magnetizations as they occur in the magnetic circuit of electrical machines. A four-pole rotational single sheet tester is used to generate the rotating magnetic flux inside the sample. A field-oriented control scheme is implemented to improve the control performance. The magnetization process of different non-oriented materials is analyzed and compared.

Hydrology-oriented forest management trade-offs. A modeling framework coupling field data, simulation results and Bayesian Networks.

PubMed

Garcia-Prats, Alberto; González-Sanchis, María; Del Campo, Antonio D; Lull, Cristina

2018-10-15

Hydrology-oriented forest management sets water as key factor of the forest management for adaptation due to water is the most limiting factor in the Mediterranean forest ecosystems. The aim of this study was to apply Bayesian Network modeling to assess potential indirect effects and trade-offs when hydrology-oriented forest management is applied to a real Mediterranean forest ecosystem. Water, carbon and nitrogen cycles, and forest fire risk were included in the modeling framework. Field data from experimental plots were employed to calibrate and validate the mechanistic Biome-BGCMuSo model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere. Many other 50-year long scenarios with different conditions to the ones measured in the field experiment were simulated and the outcomes employed to build the Bayesian Network in a linked chain of models. Hydrology-oriented forest management was very positive insofar as more water was made available to the stand because of an interception reduction. This resource was made available to the stand, which increased the evapotranspiration and its components, the soil water content and a slightly increase of deep percolation. Conversely, Stemflow was drastically reduced. No effect was observed on Runof due to the thinning treatment. The soil organic carbon content was also increased which in turn caused a greater respiration. The long-term effect of the thinning treatment on the LAI was very positive. This was undoubtedly due to the increased vigor generated by the greater availability of water and nutrients for the stand and the reduction of competence between trees. This greater activity resulted in an increase in GPP and vegetation carbon, and therefore, we would expect a higher carbon sequestration. It is worth emphasizing that this extra amount of water and nutrients was taken up by the stand and did not entail any loss of nutrients. Copyright © 2018 Elsevier B.V. All rights reserved.

Demanding Epistemic Democracy and Indirect Civics Pedagogy: The Performance-Oriented Music Ensemble

ERIC Educational Resources Information Center

Pyrcz, Greg; MacLean, Tessa; Hopkins, Mark

2017-01-01

The participation of young adults in performance-oriented music ensembles can be seen to enhance democratic capacities and virtues. Much, however, turns on the particular conception of democracy at work. Although contemporary currents in music education tend towards models of liberal and participatory democracy to govern music ensembles, this…

Instructional characteristics in mathematics classrooms: relationships to achievement goal orientation and student engagement

NASA Astrophysics Data System (ADS)

Lazarides, Rebecca; Rubach, Charlott

2017-02-01

This longitudinal study examined relationships between student-perceived teaching for meaning, support for autonomy, and competence in mathematic classrooms (Time 1), and students' achievement goal orientations and engagement in mathematics 6 months later (Time 2). We tested whether student-perceived instructional characteristics at Time 1 indirectly related to student engagement at Time 2, via their achievement goal orientations (Time 2), and, whether student gender moderated these relationships. Participants were ninth and tenth graders (55.2% girls) from 46 classrooms in ten secondary schools in Berlin, Germany. Only data from students who participated at both timepoints were included (N = 746 out of total at Time 1 1118; dropout 33.27%). Longitudinal structural equation modeling showed that student-perceived teaching for meaning and support for competence indirectly predicted intrinsic motivation and effort, via students' mastery goal orientation. These paths were equivalent for girls and boys. The findings are significant for mathematics education, in identifying motivational processes that partly explain the relationships between student-perceived teaching for meaning and competence support and intrinsic motivation and effort in mathematics.

Measurement of the orientation of buffer-gas-cooled, electrostatically-guided ammonia molecules

NASA Astrophysics Data System (ADS)

Steer, Edward W.; Petralia, Lorenzo S.; Western, Colin M.; Heazlewood, Brianna R.; Softley, Timothy P.

2017-02-01

The extent to which the spatial orientation of internally and translationally cold ammonia molecules can be controlled as molecules pass out of a quadrupole guide and through different electric field regions is examined. Ammonia molecules are collisionally cooled in a buffer gas cell, and are subsequently guided by a three-bend electrostatic quadrupole into a detection chamber. The orientation of ammonia molecules is probed using (2 + 1) resonance-enhanced multiphoton ionisation (REMPI), with the laser polarisation axis aligned both parallel and perpendicular to the time-of-flight axis. Even with the presence of a near-zero field region, the ammonia REMPI spectra indicate some retention of orientation. Monte Carlo simulations propagating the time-dependent Schrödinger equation in a full basis set including the hyperfine interaction enable the orientation of ammonia molecules to be calculated - with respect to both the local field direction and a space-fixed axis - as the molecules pass through different electric field regions. The simulations indicate that the orientation of ∼95% of ammonia molecules in JK =11 could be achieved with the application of a small bias voltage (17 V) to the mesh separating the quadrupole and detection regions. Following the recent combination of the buffer gas cell and quadrupole guide apparatus with a linear Paul ion trap, this result could enable one to examine the influence of molecular orientation on ion-molecule reaction dynamics and kinetics.

Visual-Spatial Orienting in Autism.

ERIC Educational Resources Information Center

Wainwright, J. Ann; Bryson, Susan E.

1996-01-01

Visual-spatial orienting in 10 high-functioning adults with autism was examined. Compared to controls, subjects responded faster to central than to lateral stimuli, and showed a left visual field advantage for stimulus detection only when laterally presented. Abnormalities in attention shifting and coordination of attentional and motor systems are…

Effect of magnetic pulses on Caribbean spiny lobsters: implications for magnetoreception.

PubMed

Ernst, David A; Lohmann, Kenneth J

2016-06-15

The Caribbean spiny lobster, Panulirus argus, is a migratory crustacean that uses Earth's magnetic field as a navigational cue, but how these lobsters detect magnetic fields is not known. Magnetic material thought to be magnetite has previously been detected in spiny lobsters, but its role in magnetoreception, if any, remains unclear. As a first step toward investigating whether lobsters might have magnetite-based magnetoreceptors, we subjected lobsters to strong, pulsed magnetic fields capable of reversing the magnetic dipole moment of biogenic magnetite crystals. Lobsters were subjected to a single pulse directed from posterior to anterior and either: (1) parallel to the horizontal component of the geomagnetic field (i.e. toward magnetic north); or (2) antiparallel to the horizontal field (i.e. toward magnetic south). An additional control group was handled but not subjected to a magnetic pulse. After treatment, each lobster was tethered in a water-filled arena located within 200 m of the capture location and allowed to walk in any direction. Control lobsters walked in seemingly random directions and were not significantly oriented as a group. In contrast, the two groups exposed to pulsed fields were significantly oriented in approximately opposite directions. Lobsters subjected to a magnetic pulse applied parallel to the geomagnetic horizontal component walked westward; those subjected to a pulse directed antiparallel to the geomagnetic horizontal component oriented approximately northeast. The finding that a magnetic pulse alters subsequent orientation behavior is consistent with the hypothesis that magnetoreception in spiny lobsters is based at least partly on magnetite-based magnetoreceptors. © 2016. Published by The Company of Biologists Ltd.

Individual Differences in Men’s Misperception of Women’s Sexual Intent: Application and Extension of the Confluence Model

PubMed Central

Wegner, Rhiana; Abbey, Antonia

2016-01-01

Men are more likely than women to misperceive a cross-sex companion’s degree of sexual interest. The current study extends previous research by using the confluence model (Malamuth et al., 1991) to examine how narcissism and impulsive sensation-seeking are directly and indirectly associated with men’s misperception of women’s sexual interest. A community sample of young, single men (N = 470) completed audio computer-assisted self-interviews. Using path analyses, hostile masculinity and impersonal sexual orientation were proximal predictors of men’s misperception of women’s sexual intent. Additionally, narcissism was indirectly related to men’s misperception through hostile masculinity. Impulsive sensation-seeking was directly and indirectly related to men’s misperceptions through impersonal sexual orientation. Although there was a bivariate relationship between alcohol consumption and misperception, this relationship was not significant in the path model. Overall, these findings demonstrate the importance of considering how personality traits increase the risk for misperception. PMID:26834303

Control of proliferation rate of N27 dopaminergic neurons using Transcranial Magnetic Stimulation orientation

NASA Astrophysics Data System (ADS)

Meng, Yiwen; Hadimani, Ravi; Anantharam, Vellareddy; Kanthasamy, Anumantha; Jiles, David

2015-03-01

Transcranial magnetic stimulation (TMS) has been used to investigate possible treatments for a variety of neurological disorders. However, the effect that magnetic fields have on neurons has not been well documented in the literature. We have investigated the effect of different orientation of magnetic field generated by TMS coils with a monophasic stimulator on the proliferation rate of N27 neuronal cells cultured in flasks and multi-well plates. The proliferation rate of neurons would increase by exposed horizontally adherent N27 cells to a magnetic field pointing upward through the neuronal proliferation layer compared with the control group. On the other hand, proliferation rate would decrease in cells exposed to a magnetic field pointing downward through the neuronal growth layer compared with the control group. We confirmed results obtained from the Trypan-blue and automatic cell counting methods with those from the CyQuant and MTS cell viability assays. Our findings could have important implications for the preclinical development of TMS treatments of neurological disorders and represents a new method to control the proliferation rate of neuronal cells.

The anticipated transition to adulthood: effects of culture and individual experience on Polish and Finnish adolescents' future orientations.

PubMed

Trempala, J; Malmberg, L E

1998-05-01

The purpose of this study was to describe the effect of a set of individual resources and cultural factors on adolescents' probability estimations of the occurrence of positive future events in three life domains: education, occupation, and family. The hypothesis was that the effects of culture and individual resources are interwoven in the formation process of future orientation. The sample consisted of 352 17-year-old Polish and Finnish girls and boys from vocational and upper secondary schools. The 78-item questionnaire developed by the authors was used to measure different aspects of future orientation (probability, valence, and extension of future events in three life domains) and individual resources (self-esteem, control beliefs, and social knowledge about normatively and the generation gap). Data analysis showed that culture separately affected individual resources and adolescents' expectations. However, the results broadly confirmed the thesis that the culture has a limited effect on adolescents' expectations of the occurrence of future events. Moreover, these data suggested that the influence of sociocultural differences on adolescents' probability estimations is indirect. In the context of the presented data, the authors discuss their model of future orientation.

Control over Janus micromotors by the strength of a magnetic field

NASA Astrophysics Data System (ADS)

Baraban, Larysa; Makarov, Denys; Schmidt, Oliver G.; Cuniberti, Gianaurelio; Leiderer, Paul; Erbe, Artur

2013-01-01

For transportation of molecules or biological cells using artificial motors, the control over their motion, i.e. direction and speed of transfer, is important. Here, we demonstrate that modification of the velocity and orientation of a magnetic Janus particle can be efficiently controlled by tuning the strength of an applied homogeneous magnetic field. Interestingly, by keeping the same orientation of the magnetic field but changing its magnitude not only the velocity of capped particles can be altered but even their direction of motion can be reversed. We put forth a simple qualitative model, which allows us to explain this intriguing observation.For transportation of molecules or biological cells using artificial motors, the control over their motion, i.e. direction and speed of transfer, is important. Here, we demonstrate that modification of the velocity and orientation of a magnetic Janus particle can be efficiently controlled by tuning the strength of an applied homogeneous magnetic field. Interestingly, by keeping the same orientation of the magnetic field but changing its magnitude not only the velocity of capped particles can be altered but even their direction of motion can be reversed. We put forth a simple qualitative model, which allows us to explain this intriguing observation. Electronic supplementary information (ESI) available: Videos (1-3) describe the behavior of the magnetic Janus micromotors at different magnetic fields applied. The magnetic field is always applied along the positive direction of the y-axis. All the movies are recorded at the same frame rate of 21 images per second. Experiments were performed at 30 wt% of hydrogen peroxide in aqueous solution. Video 1 shows the motion of the Janus micromotors when a small magnetic field is applied (B = 0.2 mT). The particle is propelled in the direction ``opposite to the cap'' with a velocity of about 6 μm s-1. Video 2 displays the motion of the same Janus bead when an intermediately strong magnetic field is applied (B = 1.5 mT). The particle still moves in the direction ``opposite to the cap'', but with a much smaller velocity of about 1 μm s-1. Video 3 shows the behavior of the Janus micromotor, exposed to the high magnetic field B = 2.2 mT. The particle moves in the direction ``towards the cap'' with the speed of about 4 μm s-1. See DOI: 10.1039/c2nr32662k

Intergenerational Transmission of Tridimensional Cultural Orientations in Chinese American Families: The Role of Bicultural Socialization

PubMed Central

Kim, Su Yeong; Hou, Yang

2016-01-01

It is important to understand the acculturation process of ethnic minority youth: To which cultures do they orient, and how do their cultural orientations develop? The present study tests a tridimensional acculturation model in Chinese American families and examines a potential mechanism through which parental cultural orientations may relate to adolescent cultural orientations. Participants were 350 Chinese American adolescents (Mage =17.04, 58% female) and their parents in Northern California. Results support the tridimensional acculturation model by demonstrating moderate associations among Chinese American orientation, Chinese orientation, and American orientation; our findings also point to a unique effect of parental Chinese American orientation on parental bicultural socialization beliefs. Most importantly, we identified an indirect pathway from parental to adolescents’ Chinese American orientation through adolescents’ internalization of parental bicultural socialization beliefs. PMID:26781739

On Self‐Love and Outgroup Hate: Opposite Effects of Narcissism on Prejudice via Social Dominance Orientation and Right‐Wing Authoritarianism

PubMed Central

Dhont, Kristof; Makwana, Arti P.

2017-01-01

Abstract Previous research has obtained mixed findings as to whether feelings of self‐worth are positively or negatively related to right‐wing ideological beliefs and prejudice. We propose to clarify the link between self‐worth and ideology by distinguishing between narcissistic and non‐narcissistic self‐evaluations as well as between different dimensions of ideological attitudes. Four studies, conducted in three different socio‐political contexts: the UK (Study 1, N = 422), the US (Studies 2 and 3, Ns = 471 and 289, respectively), and Poland (Study 4, N = 775), investigated the associations between narcissistic and non‐narcissistic self‐evaluations, social dominance orientation (SDO), right‐wing authoritarianism (RWA), and ethnic prejudice. Confirming our hypotheses, the results consistently showed that after controlling for self‐esteem, narcissistic self‐evaluation was positively associated with SDO (accounting for RWA), yet negatively associated with RWA (accounting for SDO). These associations were similar after controlling for psychopathy and Machiavellianism (Study 3) as well as collective narcissism and Big Five personality characteristics (Study 4). Studies 2–4 additionally demonstrated that narcissistic self‐evaluation was indirectly positively associated with prejudice through higher SDO (free of RWA) but indirectly negatively associated with prejudice through lower RWA (free of SDO). Implications for understanding the role of self‐evaluation in right‐wing ideological attitudes and prejudice are discussed. Copyright © 2017 The Authors. European Journal of Personality published by John Wiley & Sons Ltd on behalf of European Association of Personality Psychology PMID:28983151

Beyond Being Present: Learning-Oriented Leadership in the Daily Work of Middle Managers

ERIC Educational Resources Information Center

Döös, Marianne; Johansson, Peter; Wilhelmson, Lena

2015-01-01

Purpose: This paper aims to contribute to the understanding of learning-oriented leadership as being integrated in managers' daily work. The particular focus is on managers' efforts to change how work is carried out through indirect acts of influence. In their daily work, managers influence the organisation's learning conditions in ways that go…

Controlled sample orientation and rotation in an acoustic levitator

NASA Technical Reports Server (NTRS)

Barmatz, Martin B. (Inventor); Gaspar, Mark S. (Inventor); Trinh, Eugene H. (Inventor)

1988-01-01

A system is described for use with acoustic levitators, which can prevent rotation of a levitated object or control its orientation and/or rotation. The acoustic field is made nonsymmetrical about the axis of the levitator, to produce an orienting torque that resists sample rotation. In one system, a perturbating reflector is located on one side of the axis of the levitator, at a location near the levitated object. In another system, the main reflector surface towards which incoming acoustic waves are directed is nonsymmetrically curved about the axis of the levitator. The levitated object can be reoriented or rotated in a controlled manner by repositioning the reflector producing the nonsymmetry.

Both the "What" and "Why" of Youth Sports Participation Matter; a Conditional Process Analysis.

PubMed

Gjesdal, Siv; Appleton, Paul R; Ommundsen, Yngvar

2017-01-01

This study builds on previous research combining achievement goal orientation from Achievement Goal Theory and motivational regulation from Self-Determination Theory. The aim was to assess the combination of the "what" and "why" of youth sport activity, and how it relates to the need for competence and self-esteem. Achievement goal orientation, specifically task and ego, was employed to represent the "what", whilst intrinsic and external regulation reflected the "why". Based on a sample of 496 youth sports participants, structural equation modeling with a bootstrapping procedure was used to examine whether the indirect relationship between achievement goal orientation and self-esteem was conditional to motivational regulation. The results show partial support for the conditional process models. Specifically, task orientation was indirectly linked with self-esteem through competence need, and the relationship was stronger with higher levels of intrinsic regulation for sport. Furthermore, ego orientation was negatively associated with self-esteem through a positive relationship with competence frustration. However, this relationship emerged only for those higher in intrinsic regulation. External regulation did not emerge as a moderator, but presented a positive relationship with competence frustration. Findings are discussed in light of both Achievement Goal Theory and Self-Determination Theory, and underline the importance of considering both the "what" and "why" when attempting to understand motivation in youth sport.

Large magnetoresistance in a directionally solidified Ni44.5Co5.1Mn37.1In13.3 magnetic shape memory alloy

NASA Astrophysics Data System (ADS)

Li, Zongbin; Hu, Wei; Chen, Fenghua; Zhang, Mingang; Li, Zhenzhuang; Yang, Bo; Zhao, Xiang; Zuo, Liang

2018-04-01

Polycrystalline Ni44.5Co5.1Mn37.1In13.3 alloy with coarse columnar-shaped grains and 〈0 0 1〉A preferred orientation was prepared by directional solidification. Due to the strong magnetostructural coupling, inverse martensitic transformation can be induced by the magnetic field, resulting in large negative magnetoresistance up to -58% under the field of 3 T. Such significant field controlled functional behaviors should be attributed to the coarse grains and strong preferred orientation in the directionally solidified alloy.

Direct and indirect measurement of the magnetocaloric effect in bulk and nanostructured Ni-Mn-In Heusler alloy

NASA Astrophysics Data System (ADS)

Ghahremani, Mohammadreza; Aslani, Amir; Hosseinnia, Marjan; Bennett, Lawrence H.; Della Torre, Edward

2018-05-01

A systematic study of the magnetocaloric effect of a Ni51Mn33.4In15.6 Heusler alloy converted to nanoparticles via high energy ball-milling technique in the temperature range of 270 to 310 K has been performed. The properties of the particles were characterized by x-ray diffraction, electron microscopy, and magnetometer techniques. Isothermal magnetic field variation of magnetization exhibits field hysteresis in bulk Ni51Mn33.4In15.6 alloy across the martensitic transition which significantly lessened in the nanoparticles. The magnetocaloric effects of the bulk and nanoparticle samples were measured both with direct method, through our state of the art direct test bed apparatus with controllability over the applied fields and temperatures, as well as an indirect method through Maxwell and thermodynamic equations. In direct measurements, nanoparticle sample's critical temperature decreased by 6 K, but its magnetocaloric effect enhanced by 17% over the bulk counterpart. Additionally, when comparing the direct and indirect magnetocaloric curves, the direct method showed 14% less adiabatic temperature change in the bulk and 5% less adiabatic temperature change in the nanostructured sample.

BiFeO3 Thin Films: A Playground for Exploring Electric-Field Control of Multifunctionalities

NASA Astrophysics Data System (ADS)

Yang, Jan-Chi; He, Qing; Yu, Pu; Chu, Ying-Hao

2015-07-01

A promising approach to the next generation of low-power, functional, and green nanoelectronics relies on advances in the electric-field control of lattice, charge, orbital, and spin degrees of freedom in novel materials. The possibility of electric-field control of these multiple materials functionalities offers interesting options across a range of modern technologies, including information communication, computing processes, data storage, active components, and functional electronics. This article reviews electric-field control and modulation of various degrees of freedom through the medium of multiferroic BiFeO3. Coexisting order parameters and inherent couplings in this materials system form a potent playground, enabling direct and indirect manipulation to obtain intriguing properties and functionalities with an electric stimulus. An in-depth understanding of those electrically controlled phenomena and breakthroughs is highlighted, paving a new route toward multifunctional nanoelectronics. This article concludes with a brief discussion on foreseeable challenges as well as future directions.

Mapping Strain Gradients in the FIB-Structured InGaN/GaN Multilayered Films with 3D X-ray Microbeam

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

Barabash, Rozaliya; Gao, Yanfei; Ice, Gene E

2010-01-01

This research presents a combined experimental-modeling study of lattice rotations and deviatoric strain gradients induced by focused-ion beam (FIB) milling in nitride heterostructures. 3D X-ray polychromatic microdiffraction (PXM) is used to map the local lattice orientation distribution in FIB-structured areas. Results are discussed in connection with microphotoluminescence ({mu}-PL), fluorescent analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) data. It is demonstrated that FIB-milling causes both direct and indirect damage to the InGaN/GaN layers. In films subjected to direct ion beam impact, a narrow amorphidized top layer is formed. Near the milling area, FIB-induced stress relaxation and formation ofmore » complicated 3D strain fields are observed. The resulting lattice orientation changes are found to correlate with a decrease and/or loss of PL intensity, and agree well with finite element simulations of the three-dimensional strain fields near the relaxed trenches. Experimentally, it is found that the lattice surface normal has an in-plane rotation, which only appears in simulations when the GaN-substrate lattice mismatch annihilates the InGaN-substrate mismatch. This behavior further supports the notion that the film/substrate interface is incoherent.« less

Mapping strain gradients in the FIB-structured InGaN/GaN multilayered films with 3D x-ray microbeam.

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

Barabash, R. I.; Gao, Y. F.; Ice, G. E.

2010-11-25

This research presents a combined experimental-modeling study of lattice rotations and deviatoric strain gradients induced by focused-ion beam (FIB) milling in nitride heterostructures. 3D X-ray polychromatic microdiffraction (PXM) is used to map the local lattice orientation distribution in FIB-structured areas. Results are discussed in connection with microphotoluminescence ({mu}-PL), fluorescent analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) data. It is demonstrated that FIB-milling causes both direct and indirect damage to the InGaN/GaN layers. In films subjected to direct ion beam impact, a narrow amorphidized top layer is formed. Near the milling area, FIB-induced stress relaxation and formation ofmore » complicated 3D strain fields are observed. The resulting lattice orientation changes are found to correlate with a decrease and/or loss of PL intensity, and agree well with finite element simulations of the three-dimensional strain fields near the relaxed trenches. Experimentally, it is found that the lattice surface normal has an in-plane rotation, which only appears in simulations when the GaN-substrate lattice mismatch annihilates the InGaN-substrate mismatch. This behavior further supports the notion that the film/substrate interface is incoherent.« less

Achievement goals as mediators of the relationship between competence beliefs and test anxiety.

PubMed

Putwain, David W; Symes, Wendy

2012-06-01

Previous work suggests that the expectation of failure is related to higher test anxiety and achievement goals grounded in a fear of failure. To test the hypothesis, based on the work of Elliot and Pekrun (2007), that the relationship between perceived competence and test anxiety is mediated by achievement goal orientations. Self-report data were collected from 275 students in post-compulsory education following courses in A Level Psychology. Competence beliefs were inversely related to the worry and tension components of test anxiety, both directly and indirectly through a performance-avoidance goal orientation. A mastery-avoidance goal orientation offered an indirect route from competence beliefs to worry only. These findings provide partial support for Elliot and Pekrun's (2007) model. Although significant mediating effects were found for mastery-avoidance and performance-avoidance goals, they were small and there may be other mechanisms to account for the relations between competence beliefs and test anxiety. ©2011 The British Psychological Society.

[Design of Adjustable Magnetic Field Generating Device in the Capsule Endoscope Tracking System].

PubMed

Ruan, Chao; Guo, Xudong; Yang, Fei

2015-08-01

The capsule endoscope swallowed from the mouth into the digestive system can capture the images of important gastrointestinal tract regions. It can compensate for the blind spot of traditional endoscopic techniques. It enables inspection of the digestive system without discomfort or need for sedation. However, currently available clinical capsule endoscope has some limitations such as the diagnostic information being not able to correspond to the orientation in the body, since the doctor is unable to control the capsule motion and orientation. To solve the problem, it is significant to track the position and orientation of the capsule in the human body. This study presents an AC excitation wireless tracking method in the capsule endoscope, and the sensor embedded in the capsule can measure the magnetic field generated by excitation coil. And then the position and orientation of the capsule can be obtained by solving a magnetic field inverse problem. Since the magnetic field decays with distance dramatically, the dynamic range of the received signal spans three orders of magnitude, we designed an adjustable alternating magnetic field generating device. The device can adjust the strength of the alternating magnetic field automatically through the feedback signal from the sensor. The prototype experiment showed that the adjustable magnetic field generating device was feasible. It could realize the automatic adjustment of the magnetic field strength successfully, and improve the tracking accuracy.

Effect of resonant magnetic perturbations on three dimensional equilibria in the Madison Symmetric Torus reversed-field pinch

NASA Astrophysics Data System (ADS)

Munaretto, S.; Chapman, B. E.; Nornberg, M. D.; Boguski, J.; DuBois, A. M.; Almagri, A. F.; Sarff, J. S.

2016-05-01

The orientation of 3D equilibria in the Madison Symmetric Torus (MST) [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] reversed-field pinch can now be controlled with a resonant magnetic perturbation (RMP). Absent the RMP, the orientation of the stationary 3D equilibrium varies from shot to shot in a semi-random manner, making its diagnosis difficult. Produced with a poloidal array of saddle coils at the vertical insulated cut in MST's thick conducting shell, an m = 1 RMP with an amplitude br/B ˜ 10% forces the 3D structure into any desired orientation relative to MST's diagnostics. This control has led to improved diagnosis, revealing enhancements in both the central electron temperature and density. With sufficient amplitude, the RMP also inhibits the generation of high-energy (>20 keV) electrons, which otherwise emerge due to a reduction in magnetic stochasticity in the core. Field line tracing reveals that the RMP reintroduces stochasticity to the core. A m = 3 RMP of similar amplitude has little effect on the magnetic topology or the high-energy electrons.

Transport of Indirect Excitons in High Magnetic Fields

NASA Astrophysics Data System (ADS)

Dorow, C. J.; Kuznetsova, Y. Y.; Calman, E. V.; Butov, L. V.; Wilkes, J.; Campman, K. L.; Gossard, A. C.

Spatially- and spectrally-resolved photoluminescence measurements of indirect excitons in high magnetic fields are presented. The high magnetic field regime for excitons is realized when the cyclotron splitting compares to the exciton binding energy. Due to small mass and binding energy, the high magnetic field regime for excitons is achievable in lab, requiring a few Tesla. Long indirect exciton lifetimes allow large exciton transport distances before recombination, giving an opportunity to study transport and relaxation kinetics of indirect magnetoexcitons via optical imaging. Indirect excitons in several Landau level states are realized. 0e -0h indirect magnetoexcitons (formed from electrons and holes at zeroth Landau levels) travel over large distances and form an emission ring around the excitation spot. In contrast, the 1e -1h and 2e -2h states do not exhibit long transport distances, and the spatial profiles of the emission closely follow the laser excitation. The 0e -0h indirect magnetoexciton transport distance reduces with increasing magnetic field. Accompanying theoretical work explains these effects in terms of magnetoexciton energy relaxation and effective mass enhancement. Supported by NSF Grant No. 1407277. J.W. was supported by the EPSRC (Grant EP/L022990/1). C.J.D. was supported by the NSF Graduate Research Fellowship Program under Grant No. DGE-1144086.

Acculturation and Substance Use among Hispanic Early Adolescents: Investigating the Mediating Roles of Acculturative Stress and Self-Esteem

ERIC Educational Resources Information Center

Zamboanga, Byron L.; Schwartz, Seth J.; Jarvis, Lorna Hernandez; Van Tyne, Kathryne

2009-01-01

We examined the extent to which Hispanic orientation and American orientation are associated with substance use (cigarette, alcohol, and marijuana) both directly and indirectly through acculturative stress and self-esteem. Participants were 347 Hispanic early adolescents (50.7% male; mean age = 12.57, SD = 0.92, range 11-15) from two middle…

Electronic Structures of Free-Standing Nanowires made from Indirect Bandgap Semiconductor Gallium Phosphide

PubMed Central

Liao, Gaohua; Luo, Ning; Chen, Ke-Qiu; Xu, H. Q.

2016-01-01

We present a theoretical study of the electronic structures of freestanding nanowires made from gallium phosphide (GaP)—a III-V semiconductor with an indirect bulk bandgap. We consider [001]-oriented GaP nanowires with square and rectangular cross sections, and [111]-oriented GaP nanowires with hexagonal cross sections. Based on tight binding models, both the band structures and wave functions of the nanowires are calculated. For the [001]-oriented GaP nanowires, the bands show anti-crossing structures, while the bands of the [111]-oriented nanowires display crossing structures. Two minima are observed in the conduction bands, while the maximum of the valence bands is always at the Γ-point. Using double group theory, we analyze the symmetry properties of the lowest conduction band states and highest valence band states of GaP nanowires with different sizes and directions. The band state wave functions of the lowest conduction bands and the highest valence bands of the nanowires are evaluated by spatial probability distributions. For practical use, we fit the confinement energies of the electrons and holes in the nanowires to obtain an empirical formula. PMID:27307081

Roughness of Ti Substrates for Control of the Preferred Orientation of TiO 2 Nanotube Arrays as a New Orientation Factor

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

Seong, Won Mo; Kim, Dong Hoe; Park, Ik Jae

2015-06-11

We report the surface roughness of a Ti substrate as a critical factor for controlling the degree of the preferred orientation of anatase TiO2 nanotube arrays (NTAs) which are synthesized by anodization and a subsequent annealing process. The degree of the preferred orientation to the (004) plane of the anatase crystal structure has a strong dependency on the root-mean-square roughness (Sq) of the initial Ti substrate when the roughness-controlled substrates are anodized in an ethylene glycol-based electrolyte containing ~2 wt % of water. Highly preferred oriented NTAs were obtained from low-Sq (<10 nm) substrates, which were accompanied by uniform poremore » distribution and low concentration of hydroxyl ions in as-anodized amorphous NTAs. The mechanism of the preferred oriented crystallization of nanometer-scaled tube walls is explained considering the microscopic geometrical uniformity of the oxide barrier and nanopores at the early stage of anodization, which affected the local electric field and thus the insertion of the hydroxyl group into the amorphous TiO2 tube walls.« less

Lost at sea: ocean acidification undermines larval fish orientation via altered hearing and marine soundscape modification.

PubMed

Rossi, Tullio; Nagelkerken, Ivan; Pistevos, Jennifer C A; Connell, Sean D

2016-01-01

The dispersal of larvae and their settlement to suitable habitat is fundamental to the replenishment of marine populations and the communities in which they live. Sound plays an important role in this process because for larvae of various species, it acts as an orientational cue towards suitable settlement habitat. Because marine sounds are largely of biological origin, they not only carry information about the location of potential habitat, but also information about the quality of habitat. While ocean acidification is known to affect a wide range of marine organisms and processes, its effect on marine soundscapes and its reception by navigating oceanic larvae remains unknown. Here, we show that ocean acidification causes a switch in role of present-day soundscapes from attractor to repellent in the auditory preferences in a temperate larval fish. Using natural CO2 vents as analogues of future ocean conditions, we further reveal that ocean acidification can impact marine soundscapes by profoundly diminishing their biological sound production. An altered soundscape poorer in biological cues indirectly penalizes oceanic larvae at settlement stage because both control and CO2-treated fish larvae showed lack of any response to such future soundscapes. These indirect and direct effects of ocean acidification put at risk the complex processes of larval dispersal and settlement. © 2016 The Author(s).

The Relationship Between Poor Quality of Life and Desire to Hasten Death: A Multiple Mediation Model Examining the Contributions of Depression, Demoralization, Loss of Control, and Low Self-worth.

PubMed

Robinson, Sophie; Kissane, David W; Brooker, Joanne; Hempton, Courtney; Burney, Susan

2017-02-01

The risk of suicide is elevated in palliative care patients compared with the general population. Various psychological factors, including depression, demoralization, loss of control, and low self-worth, have been associated with a desire to hasten death. The aim of this study was to investigate whether depression, demoralization, loss of control, and low self-worth mediated the relationship between global quality of life and desire to hasten death. A sample of 162 palliative care patients completed measures of global quality of life, depression, demoralization, perceived control, self-worth, and desire to hasten death. A multiple mediation model with bootstrapping sampling tested the total (combined) indirect effect and individual indirect effects of depression, the two subscales of demoralization (Meaning and Purpose, and Distress and Coping Ability), perceived control, and self-worth. Depressive symptoms, loss of meaning and purpose, loss of control, and low self-worth mediated the direct effect of global quality of life on desire to hasten death. The Distress and Coping Ability component of demoralization was not a significant mediator. Depression, loss of meaning and purpose, loss of control, and low self-worth are strong clinical markers for desire to hasten death. Targeting these symptoms through existentially oriented therapies, such as meaning-centered therapy, may ameliorate suicidal thinking. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Field oriented control of induction motors

NASA Technical Reports Server (NTRS)

Burrows, Linda M.; Zinger, Don S.; Roth, Mary Ellen

1990-01-01

Induction motors have always been known for their simple rugged construction, but until lately were not suitable for variable speed or servo drives due to the inherent complexity of the controls. With the advent of field oriented control (FOC), however, the induction motor has become an attractive option for these types of drive systems. An FOC system which utilizes the pulse population modulation method to synthesize the motor drive frequencies is examined. This system allows for a variable voltage to frequency ratio and enables the user to have independent control of both the speed and torque of an induction motor. A second generation of the control boards were developed and tested with the next point of focus being the minimization of the size and complexity of these controls. Many options were considered with the best approach being the use of a digital signal processor (DSP) due to its inherent ability to quickly evaluate control algorithms. The present test results of the system and the status of the optimization process using a DSP are discussed.

Petrogenesis of Challis Volcanic Group, east-central Idaho

NASA Astrophysics Data System (ADS)

Schleiffarth, W. K.; Larson, P. B.

2013-12-01

The Eocene Challis-Kamloops volcanic belt (CKVB) extends south and east from northern British Columbia to central Idaho and is related to the paleotectonic plate interaction between the Farallon and North American plates. Numerous volcanic fields are scattered throughout the CKVB and show a wide range of eruption styles, tectonic environments, and geochemical compositions. Several volcanic fields produced calc-alkaline rocks, while others produced moderately to strongly alkaline rocks. Some volcanic fields have a significant slab component, while others show no direct evidence of subduction-related magmatism. Proposed models for tectonic controls on the CKVB include continental volcanic arc delamination of subducted slab, rifted arc, slab window, and extensional continental tectonism. However, there is no generally accepted explanation for the petrogenesis of the CKVB. The Challis Volcanic Group (CVG) of central Idaho, located in the southern portion of the belt, is the largest of the Eocene volcanic fields (25,000 km2). The CVG is of interest because it exhibits very diverse volcanic deposits and compositions and may accurately represent the CKVB. Challis volcanism was synchronous with extension along the NE-SW-trending trans-Challis fault system and resulted in similarly oriented normal faults, dikes, calderas, and exhumation of the Pioneer core complex. The CVG covers much of central Idaho with exposures extending from the Sawtooth Mountains in the west to the Lemhi and Beaverhead ranges to the east. The CVG has high alkaline contents relative to calc-alkaline subduction-related volcanic rocks, varying isotopic signatures, and prevalent extensional features. These facts, coupled with the lack of obvious orientation of volcanic fields throughout the CKVB, explain why the petrogenesis of Eocene volcanism of the inland Pacific Northwest is controversial. Rare earth element concentrations and Sr, Nd, and Pb isotope ratios show that the CVG represents a mixture of crustal and mantle material. The increasing K concentrations away from the continental margin suggest that subduction was at least indirectly or partially related to the petrogenesis of the CKVB. Plate reconstructions show that a slab window existed beneath the Pacific Northwest due to a subducting spreading center. The anomalous geochemistry of the CKVB correlates with the position of the slab window and may have influenced the petrogenesis of the CVG.

Magnetic inclination from Brazilian bricks and application to Archeomagnetic dating

NASA Astrophysics Data System (ADS)

Begnini, G. S.; Hartmann, G. A.; Trindade, R. I.

2013-05-01

The Earth's magnetic field (EMF) is recorded in archeological baked materials carrying a stable remanent magnetization. This magnetic record can be used for indirectly date the archeological material by comparison with "reference curves" of the EMF. In this work we present magnetic inclination data from two different sites in southeastern Brazil, an ancient and a modern one: (a) a sampling at the ancient sugarcane mill Engenho Central de Piracicaba (ECP, 1881-1974 AD), and (b) a controlled survey at the modern brickyard Olaria Schiavolin (OS). Both of them are located in the city of Piracicaba, São Paulo State, Brazil. Magnetic measurements included stepwise thermal and alternating field demagnetization, anisotropy of magnetic susceptibility (AMS) and low-field magnetic susceptibility vs. temperature. In OS, we collected 40 oriented bricks from 5 sampling points inside the brickyard oven in order to test the stability and reliability of their remanent magnetizations by comparing them with the local field (measured directly with a fluxgate magnetometer). We observed differences of +/- 3° between the local field and the IGRF. When magnetic inclinations are reported relative to the flat planes of the brick (the situation we face for real ancient bricks), the differences due to inclination of the burning plane and magnetic anomalies inside the oven never exceed 6°. These differences are averaged out by using a minimum of 6 bricks (~24 specimens) per sampling point to compute the inclination. In the ancient site ECP we collected 140 non-oriented bricks from 14 different walls; three of them were previously dated using historical records. Inclinations were defined using at least 6 bricks per wall, showing consistent average values within the same walls. When compared to the IGRF and GUFM1 models, the inclinations obtained for the dated walls agreed within the experimental error. We have then applied the same procedure to estimate the age of the remaining walls. Using this procedure we were able to reconstruct the architectural history of ECP building, with the following ages: ECP5 (1881-1937.5), ECP11 (1924.5-1933.5), ECP1 (1921.5-1936.5), ECP2 (1926.5-1935.5), ECP10 (1931.5-1942.5), ECP3 (1931.5-1949.5) e ECP9 (1931.5-1972.5).

Assessing the Accuracy of Ortho-image using Photogrammetric Unmanned Aerial System

NASA Astrophysics Data System (ADS)

Jeong, H. H.; Park, J. W.; Kim, J. S.; Choi, C. U.

2016-06-01

Smart-camera can not only be operated under network environment anytime and any place but also cost less than the existing photogrammetric UAV since it provides high-resolution image, 3D location and attitude data on a real-time basis from a variety of built-in sensors. This study's proposed UAV photogrammetric method, low-cost UAV and smart camera were used. The elements of interior orientation were acquired through camera calibration. The image triangulation was conducted in accordance with presence or absence of consideration of the interior orientation (IO) parameters determined by camera calibration, The Digital Elevation Model (DEM) was constructed using the image data photographed at the target area and the results of the ground control point survey. This study also analyzes the proposed method's application possibility by comparing a Ortho-image the results of the ground control point survey. Considering these study findings, it is suggested that smartphone is very feasible as a payload for UAV system. It is also expected that smartphone may be loaded onto existing UAV playing direct or indirect roles significantly.

Efferent connections of the parvalbumin-positive (PV1) nucleus in the lateral hypothalamus of rodents.

PubMed

Celio, Marco R; Babalian, Alexandre; Ha, Quan Hue; Eichenberger, Simone; Clément, Laurence; Marti, Christiane; Saper, Clifford B

2013-10-01

A solitary cluster of parvalbumin-positive neurons--the PV1 nucleus--has been observed in the lateral hypothalamus of rodents. In the present study, we mapped the efferent connections of the PV1 nucleus using nonspecific antero- and retrograde tracers in rats, and chemoselective, Cre-dependent viral constructs in parvalbumin-Cre mice. In both species, the PV1 nucleus was found to project mainly to the periaqueductal grey matter (PAG), predominantly ipsilaterally. Indirectly in rats and directly in mice, a discrete, longitudinally oriented cylindrical column of terminal fields (PV1-CTF) was identified ventrolateral to the aqueduct on the edge of the PAG. The PV1-CTF is particularly dense in the rostral portion, which is located in the supraoculomotor nucleus (Su3). It is spatially interrupted over a short stretch at the level of the trochlear nucleus and abuts caudally on a second parvalbumin-positive (PV2) nucleus. The rostral and the caudal portions of the PV1-CTF consist of axonal endings, which stem from neurons scattered throughout the PV1 nucleus. Topographically, the longitudinal orientation of the PV1-CTF accords with that of the likewise longitudinally oriented functional modules of the PAG, but overlaps none of them. Minor terminal fields were identified in a crescentic column of the lateral PAG, as well as in the Edinger-Westphal, the lateral habenular, and the laterodorsal tegmental nuclei. So far, no obvious functions have been attributed to this small, circumscribed column ventrolateral to the aqueduct, the prime target of the PV1 nucleus. © 2013 Wiley Periodicals, Inc.

Acculturation, psychological adjustment, and parenting styles of Chinese immigrant mothers in the United States.

PubMed

Yu, Jing; Cheah, Charissa S L; Calvin, Grace

2016-10-01

This study examined whether acculturation to American culture, maintenance of Chinese culture, and their interaction predicted Chinese immigrant parents' psychological adjustment and parenting styles. We hypothesized that American orientation would be associated with more positive psychological well-being and fewer depressive symptoms in immigrant mothers, which in turn would be associated with more authoritative parenting and less authoritarian parenting. The examination of the roles of Chinese orientation and the interaction of the 2 cultural orientations in relation to psychological adjustment and parenting were exploratory. Participants were 164 first-generation Chinese immigrant mothers in the United States (Mage = 37.80). Structural equation modeling was used to examine the direct and indirect effects of acculturation on psychological adjustment and parenting. Bootstrapping technique was used to explore the conditional indirect effects of acculturation on parenting as appropriate. American orientation was strongly associated with positive psychological well-being, which was in turn related to more authoritative parenting and less authoritarian parenting. Moreover, American and Chinese orientations interacted to predict depressive symptoms, which were in turn associated with more authoritarian parenting. Specifically, American orientation was negatively associated with depressive symptoms only at mean or high levels of Chinese orientation. Results suggest acculturation as a distal contextual factor and psychological adjustment as 1 critical mechanism that transmits effects of acculturation to parenting. Promoting immigrant parents' ability and comfort in the new culture independently or in conjunction with encouraging biculturalism through policy intervention efforts appear crucial for the positive adjustment of Chinese immigrant parents and children. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Acculturation, Psychological Adjustment, and Parenting Styles of Chinese Immigrant Mothers in the U.S.

PubMed Central

Yu, Jing; Cheah, Charissa S. L.; Calvin, Grace

2016-01-01

Objectives This study examined whether acculturation to American culture, maintenance of Chinese culture, and their interaction predicted Chinese immigrant parents’ psychological adjustment and parenting styles. We hypothesized that American orientation would be associated with more positive psychological well-being and fewer depressive symptoms in immigrant mothers, which in turn would be associated with more authoritative parenting and less authoritarian parenting. The examination of the roles of Chinese orientation and the interaction of the two cultural orientations in relation to psychological adjustment and parenting were exploratory. Methods Participants were 164 first-generation Chinese immigrant mothers in the U.S. (Mage = 37.80). Structural equation modeling was used to examine the direct and indirect effects of acculturation on psychological adjustment and parenting. Bootstrapping technique was used to explore the conditional indirect effects of acculturation on parenting as appropriate. Results American orientation was strongly associated with positive psychological well-being, which was in turn related to more authoritative parenting and less authoritarian parenting. Moreover, American and Chinese orientations interacted to predict depressive symptoms, which were in turn associated with more authoritarian parenting. Specifically, American orientation was negatively associated with depressive symptoms only at mean or high levels of Chinese orientation. Conclusions Results suggest acculturation as a distal contextual factor and psychological adjustment as one critical mechanism that transmits the effects of acculturation to parenting. Promoting immigrant parents’ ability and comfort in the new culture independently or in conjunction with encouraging biculturalism through policy intervention efforts appear crucial for the positive adjustment of Chinese immigrant parents and children. PMID:27077796

Improved model predictive control of resistive wall modes by error field estimator in EXTRAP T2R

NASA Astrophysics Data System (ADS)

Setiadi, A. C.; Brunsell, P. R.; Frassinetti, L.

2016-12-01

Many implementations of a model-based approach for toroidal plasma have shown better control performance compared to the conventional type of feedback controller. One prerequisite of model-based control is the availability of a control oriented model. This model can be obtained empirically through a systematic procedure called system identification. Such a model is used in this work to design a model predictive controller to stabilize multiple resistive wall modes in EXTRAP T2R reversed-field pinch. Model predictive control is an advanced control method that can optimize the future behaviour of a system. Furthermore, this paper will discuss an additional use of the empirical model which is to estimate the error field in EXTRAP T2R. Two potential methods are discussed that can estimate the error field. The error field estimator is then combined with the model predictive control and yields better radial magnetic field suppression.

Pathways to delinquency and substance use among African American youth: Does future orientation mediate the effects of peer norms and parental monitoring?

PubMed

Marotta, Phillip L; Voisin, Dexter R

2017-10-01

The following study assessed whether future orientation mediated the effects of peer norms and parental monitoring on delinquency and substance use among 549 African American adolescents. Structural equation modeling computed direct and indirect (meditational) relationships between parental monitoring and peer norms through future orientation. Parental monitoring significantly correlated with lower delinquency through future orientation ( B = -.05, standard deviation = .01, p < .01). Future orientation mediated more than quarter (27.70%) of the total effect of parental monitoring on delinquency. Overall findings underscore the importance of strengthening resilience factors for African American youth, especially those who live in low-income communities.

Influence of nonuniform magnetic fields on orientation of plant seedlings in microgravity conditions

NASA Astrophysics Data System (ADS)

Nechitailo, G. S.; Mashinsky, A. L.; Kuznetsov, A. A.; Chikov, V. M.; Kuznetsov, O. A.

2001-01-01

Experiments on the spatial behavior of the flax ( Linum usitatissimum, L.) seedlings in a nonuniform magnetic field were conducted on the orbital space stations «Salutå and «Mirå. This field can displace sensory organelles (statoliths) inside receptor cells and such displacement should cause a physiological reaction of the plant - tropistic curvature. Experiments were conducted in the custom-built «Magnetogravistatå facility, where seeds were germinated and grown for 3-4 days in a magnetic field with the dynamic factor grad(H 2/2)≈ 10 7 Oe 2/cm, then fixed on orbit and returned to Earth for analysis. It was found, that 93% of the seedlings were oriented in the field consistently with curvature in response to displacement of statoliths along the field gradient by ponderomotive magnetic forces, while control seedlings grew in the direction of the initial orientation of the seed. This suggests, that gravity receptors of plants recognized magnetic forces on statoliths as gravity, and that gravity stimulus can be substituted for plants by a force of a different physical nature.

State of the art in medical applications using non-thermal atmospheric pressure plasma

NASA Astrophysics Data System (ADS)

Tanaka, Hiromasa; Ishikawa, Kenji; Mizuno, Masaaki; Toyokuni, Shinya; Kajiyama, Hiroaki; Kikkawa, Fumitaka; Metelmann, Hans-Robert; Hori, Masaru

2017-12-01

Plasma medical science is a novel interdisciplinary field that combines studies on plasma science and medical science, with the anticipation that understanding the scientific principles governing plasma medical science will lead to innovations in the field. Non-thermal atmospheric pressure plasma has been used for medical treatments, such as for cancer, blood coagulation, and wound healing. The interactions that occur between plasma and cells/tissues have been analyzed extensively. Direct and indirect treatment of cells with plasma has broadened the applications of non-thermal atmospheric pressure plasma in medicine. Examples of indirect treatment include plasma-assisted immune-therapy and plasma-activated medium. Controlling intracellular redox balance may be key in plasma cancer treatment. Animal studies are required to test the effectiveness and safety of these treatments for future clinical applications.

Field-controllable Spin-Hall Effect of Light in Optical Crystals: A Conoscopic Mueller Matrix Analysis.

PubMed

Samlan, C T; Viswanathan, Nirmal K

2018-01-31

Electric-field applied perpendicular to the direction of propagation of paraxial beam through an optical crystal dynamically modifies the spin-orbit interaction (SOI), leading to the demonstration of controllable spin-Hall effect of light (SHEL). The electro- and piezo-optic effects of the crystal modifies the radially symmetric spatial variation in the fast-axis orientation of the crystal, resulting in a complex pattern with different topologies due to the symmetry-breaking effect of the applied field. This introduces spatially-varying Pancharatnam-Berry type geometric phase on to the paraxial beam of light, leading to the observation of SHEL in addition to the spin-to-vortex conversion. A wave-vector resolved conoscopic Mueller matrix measurement and analysis provides a first glimpse of the SHEL in the biaxial crystal, identified via the appearance of weak circular birefringence. The emergence of field-controllable fast-axis orientation of the crystal and the resulting SHEL provides a new degree of freedom for affecting and controlling the spin and orbital angular momentum of photons to unravel the rich underlying physics of optical crystals and aid in the development of active photonic spin-Hall devices.

Life Goals Increase Self-regulation Among Male Patients with Alcohol Use Disorder.

PubMed

Won, Sung-Doo; Kim, Im-Yel

2018-01-24

Alcohol use disorder (AUD) has been conceptualized as a chronic self-regulation failure. The aim of this study was to examine the most probable pathways related to self-regulation among patients with AUD. In this study, a hypothetical model was proposed that focused on the relationship between risk factors (extrinsic life goals, emotion dysregulation) and protective factors (intrinsic life goals, self-control, and abstinence self-efficacy). Male patients with AUD (N = 188) were recruited from alcohol centers of four psychiatric hospitals between March 2015 and September 2015. All participants completed psychological assessments, including the Future Oriented Goals Scale (FOGS), the Alcohol Abstinence Self-Efficacy Scale (AASE), the Brief Self-Control Scale (BSCS), and the Difficulties in Emotion Regulation Scale (DERS) as well as sociodemographic characteristics. The final model was found to be a good fit to data. In testing indirect effects, it was shown that intrinsic life goals via emotion dysregulation, self-control, and alcohol abstinence self-efficacy decreased alcohol self-regulation failure. On the other hand, extrinsic life goals via these factors increased alcohol self-regulation failure. Conclusions/Importance: These results suggest that intrinsic goals might indirectly be the important and protective factors for AUD. Moreover, the findings implicate that self-regulation through goal setting may be necessary to alleviate symptoms and improve function among patients with AUD.

Analysis of field-oriented controlled induction motor drives under sensor faults and an overview of sensorless schemes.

PubMed

Arun Dominic, D; Chelliah, Thanga Raj

2014-09-01

To obtain high dynamic performance on induction motor drives (IMD), variable voltage and variable frequency operation has to be performed by measuring speed of rotation and stator currents through sensors and fed back them to the controllers. When the sensors are undergone a fault, the stability of control system, may be designed for an industrial process, is disturbed. This paper studies the negative effects on a 12.5 hp induction motor drives when the field oriented control system is subjected to sensor faults. To illustrate the importance of this study mine hoist load diagram is considered as shaft load of the tested machine. The methods to recover the system from sensor faults are discussed. In addition, the various speed sensorless schemes are reviewed comprehensively. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Elevated lateral stress in unlithified sediment, Midcontinent, United States - geotechnical and geophysical indicators for a tectonic origin

USGS Publications Warehouse

Woolery, E.W.; Schaefer, J.A.; Wang, Z.

2003-01-01

Indirect and direct geotechnical measurements revealed the presence of high lateral earth pressure (Ko) in shallow, unlithified sediment at a site in the northernmost Mississippi embayment region of the central United States. Results from pile-load and pressuremeter tests showed maximum Ko values greater than 10; however, the complex geologic environment of the Midcontinent made defining an origin for the anomalous Ko based solely on these measurements equivocal. Although in situ sediment characteristics indicated that indirect tectonic or nontectonic geologic mechanisms that include transient overburden loads (e.g., fluvial deposition/erosion, glacial advance/retreat) and dynamic shear loads (e.g., earthquakes) were not the dominant cause, they were unable to provide indicators for a direct tectonic generation. Localized stresses induced anthropogenically by the geotechnical field tests were also considered, but ruled out as the primary origin. A high-resolution shear-wave (SH) reflection image of geologic structure in the immediate vicinity of the test site revealed compression-style neotectonism, and suggested that the elevated stress was a tectonic manifestation. Post-Paleozoic reflectors exhibit a Tertiary (?) structural inversion, as evidenced by post-Cretaceous fault displacement and pronounced positive folds in the hanging wall of the interpreted faults. The latest stratigraphic extent of the stress effects (i.e., all measurements were in the Late Cretaceous to Tertiary McNairy Formation), as well as the relationship of stress orientation with the orientation of local structure and regional stress, remain unknown. These are the subjects of ongoing studies. ?? 2003 Elsevier Science B.V. All rights reserved.

A Study on Field Emission Characteristics of Planar Graphene Layers Obtained from a Highly Oriented Pyrolyzed Graphite Block

PubMed Central

2009-01-01

This paper describes an experimental study on field emission characteristics of individual graphene layers for vacuum nanoelectronics. Graphene layers were prepared by mechanical exfoliation from a highly oriented pyrolyzed graphite block and placed on an insulating substrate, with the resulting field emission behavior investigated using a nanomanipulator operating inside a scanning electron microscope. A pair of tungsten tips controlled by the nanomanipulator enabled electric connection with the graphene layers without postfabrication. The maximum emitted current from the graphene layers was 170 nA and the turn-on voltage was 12.1 V. PMID:20596315

Investigating Factors that Generate and Maintain Variation in Migratory Orientation: A Primer for Recent and Future Work.

PubMed

Delmore, Kira E; Liedvogel, Miriam

2016-01-01

The amazing accuracy of migratory orientation performance across the animal kingdom is facilitated by the use of magnetic and celestial compass systems that provide individuals with both directional and positional information. Quantitative genetics analyses in several animal systems suggests that migratory orientation has a strong genetic component. Nevertheless, the exact identity of genes controlling orientation remains largely unknown, making it difficult to obtain an accurate understanding of this fascinating behavior on the molecular level. Here, we provide an overview of molecular genetic techniques employed thus far, highlight the pros and cons of various approaches, generalize results from species-specific studies whenever possible, and evaluate how far the field has come since early quantitative genetics studies. We emphasize the importance of examining different levels of molecular control, and outline how future studies can take advantage of high-resolution tracking and sequencing techniques to characterize the genomic architecture of migratory orientation.

Both the “What” and “Why” of Youth Sports Participation Matter; a Conditional Process Analysis

PubMed Central

Gjesdal, Siv; Appleton, Paul R.; Ommundsen, Yngvar

2017-01-01

This study builds on previous research combining achievement goal orientation from Achievement Goal Theory and motivational regulation from Self-Determination Theory. The aim was to assess the combination of the “what” and “why” of youth sport activity, and how it relates to the need for competence and self-esteem. Achievement goal orientation, specifically task and ego, was employed to represent the “what”, whilst intrinsic and external regulation reflected the “why”. Based on a sample of 496 youth sports participants, structural equation modeling with a bootstrapping procedure was used to examine whether the indirect relationship between achievement goal orientation and self-esteem was conditional to motivational regulation. The results show partial support for the conditional process models. Specifically, task orientation was indirectly linked with self-esteem through competence need, and the relationship was stronger with higher levels of intrinsic regulation for sport. Furthermore, ego orientation was negatively associated with self-esteem through a positive relationship with competence frustration. However, this relationship emerged only for those higher in intrinsic regulation. External regulation did not emerge as a moderator, but presented a positive relationship with competence frustration. Findings are discussed in light of both Achievement Goal Theory and Self-Determination Theory, and underline the importance of considering both the “what” and “why” when attempting to understand motivation in youth sport. PMID:28491048

Direct and indirect punishment among strangers in the field

PubMed Central

Balafoutas, Loukas; Nikiforakis, Nikos; Rockenbach, Bettina

2014-01-01

Many interactions in modern human societies are among strangers. Explaining cooperation in such interactions is challenging. The two most prominent explanations critically depend on individuals’ willingness to punish defectors: In models of direct punishment, individuals punish antisocial behavior at a personal cost, whereas in models of indirect reciprocity, they punish indirectly by withholding rewards. We investigate these competing explanations in a field experiment with real-life interactions among strangers. We find clear evidence of both direct and indirect punishment. Direct punishment is not rewarded by strangers and, in line with models of indirect reciprocity, is crowded out by indirect punishment opportunities. The existence of direct and indirect punishment in daily life indicates the importance of both means for understanding the evolution of cooperation. PMID:25349390

Direct and indirect punishment among strangers in the field.

PubMed

Balafoutas, Loukas; Nikiforakis, Nikos; Rockenbach, Bettina

2014-11-11

Many interactions in modern human societies are among strangers. Explaining cooperation in such interactions is challenging. The two most prominent explanations critically depend on individuals' willingness to punish defectors: In models of direct punishment, individuals punish antisocial behavior at a personal cost, whereas in models of indirect reciprocity, they punish indirectly by withholding rewards. We investigate these competing explanations in a field experiment with real-life interactions among strangers. We find clear evidence of both direct and indirect punishment. Direct punishment is not rewarded by strangers and, in line with models of indirect reciprocity, is crowded out by indirect punishment opportunities. The existence of direct and indirect punishment in daily life indicates the importance of both means for understanding the evolution of cooperation.

Spatially resolved and time-resolved imaging of transport of indirect excitons in high magnetic fields

NASA Astrophysics Data System (ADS)

Dorow, C. J.; Hasling, M. W.; Calman, E. V.; Butov, L. V.; Wilkes, J.; Campman, K. L.; Gossard, A. C.

2017-06-01

We present the direct measurements of magnetoexciton transport. Excitons give the opportunity to realize the high magnetic-field regime for composite bosons with magnetic fields of a few tesla. Long lifetimes of indirect excitons allow the study of kinetics of magnetoexciton transport with time-resolved optical imaging of exciton photoluminescence. We performed spatially, spectrally, and time-resolved optical imaging of transport of indirect excitons in high magnetic fields. We observed that an increasing magnetic field slows down magnetoexciton transport. The time-resolved measurements of the magnetoexciton transport distance allowed for an experimental estimation of the magnetoexciton diffusion coefficient. An enhancement of the exciton photoluminescence energy at the laser excitation spot was found to anticorrelate with the exciton transport distance. A theoretical model of indirect magnetoexciton transport is presented and is in agreement with the experimental data.

Characterizing Electric Field Exposed P3HT Thin Films Using Polarized-Light Spectroscopies

DOE PAGES

Bhattacharjee, Ujjal; Elshobaki, Moneim; Santra, Kalyan; ...

2016-06-23

P3HT (poly (3-hexylthiophene)) has been widely used as a donor in the active layer in organic photovoltaic devices. Although moderately high-power conversion efficiencies have been achieved with P3HT-based devices, structural details, such as the orientation of polymer units and the extent of H- and J-aggregation are not yet fully understood; and different measures have been taken to control the ordering in the material. One such measure, which we have exploited, is to apply an electric field from a Van de Graaff generator. We used fluorescence (to measure anisotropy instead of polarization, which is more commonly measured) and Raman spectroscopy tomore » characterize the order of P3HT molecules in thin films resulting from the field. We determine preferential orientations of the units in a thin film, consistent with observed hole mobility in thin-film-transistors, and observe that the apparent H-coupling strength changes when the films are exposed to oriented electrical fields during drying.« less

Cyclic Solvent Vapor Annealing for Rapid, Robust Vertical Orientation of Features in BCP Thin Films

NASA Astrophysics Data System (ADS)

Paradiso, Sean; Delaney, Kris; Fredrickson, Glenn

2015-03-01

Methods for reliably controlling block copolymer self assembly have seen much attention over the past decade as new applications for nanostructured thin films emerge in the fields of nanopatterning and lithography. While solvent assisted annealing techniques are established as flexible and simple methods for achieving long range order, solvent annealing alone exhibits a very weak thermodynamic driving force for vertically orienting domains with respect to the free surface. To address the desire for oriented features, we have investigated a cyclic solvent vapor annealing (CSVA) approach that combines the mobility benefits of solvent annealing with selective stress experienced by structures oriented parallel to the free surface as the film is repeatedly swollen with solvent and dried. Using dynamical self-consistent field theory (DSCFT) calculations, we establish the conditions under which the method significantly outperforms both static and cyclic thermal annealing and implicate the orientation selection as a consequence of the swelling/deswelling process. Our results suggest that CSVA may prove to be a potent method for the rapid formation of highly ordered, vertically oriented features in block copolymer thin films.

Field-free orientation of diatomic molecule via the linearly polarized resonant pulses

NASA Astrophysics Data System (ADS)

Li, Su-Yu; Guo, Fu-Ming; Wang, Jun; Yang, Yu-Jun; Jin, Ming-Xing

2015-10-01

We propose a scheme to coherently control the field-free orientation of NO molecule whose rotational temperature is above 0 K. It is found that the maximum molecular orientation is affected by two factors: one is the sum of the population of M = 0 rotational states and the other is their distribution, however, their distribution plays a much more significant role in molecular orientation than the sum of their population. By adopting a series of linearly polarized pulses resonant with the rotational states, the distribution of M = 0 rotational states is well rearranged. Though the number of pulses used is small, a relatively high orientation degree can be obtained. This scheme provides a promising approach to the achievement of a good orientation effect. Project supported by the National Basic Research Program of China (Grant No. 2013CB922200), the National Natural Science Foundation of China (Grant Nos. 11034003, 11474129, 11274141, and 11304116), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130061110021), and the Graduate Innovation Fund of Jilin University (Grant No. 2015091).

Electric field controlled emulsion phase contactor

DOEpatents

Scott, Timothy C.

1995-01-01

A system for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity.

Method of using an electric field controlled emulsion phase contactor

DOEpatents

Scott, Timothy C.

1993-01-01

A system for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity.

Electric field controlled emulsion phase contactor

DOEpatents

Scott, T.C.

1995-01-31

A system is described for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity. 5 figs.

Magnetic field controlled single crystal growth and surface modification of titanium alloys exposed for biocompatibility

NASA Astrophysics Data System (ADS)

Hermann, Regina; Uhlemann, Margitta; Wendrock, Horst; Gerbeth, Gunter; Büchner, Bernd

2011-03-01

The aim of this work is growth and characterisation of Ti55Nb45 (wt%) single crystals by floating-zone single crystal growth of intermetallic compounds using two-phase radio-frequency (RF) electromagnetic heating. Thereby, the process and, in particular, the flow field in the molten zone is influenced by additional magnetic fields. The growth of massive intermetallic single crystals is very often unsuccessful due to an unfavourable solid-liquid interface geometry enclosing concave fringes. It is generally known that the crystallization process stability is enhanced if the crystallization interface is convex. For this, a tailored magnetic two-phase stirrer system has been developed, which enables a controlled influence on the melt ranging from intensive inwards to outwards flows. Since Ti is favourably light, strong and biocompatible, it is one of the few materials that naturally match the requirements for implantation in the human body. Therefore, the magnetic system was applied to crystal growth of Ti alloys. The grown crystals were oriented and cut to cubes with the desired crystallographic orientations [1 0 0] and [1 0 1] normally on a plane. The electron backscatter diffraction (EBSD) technique was applied to clearly determine crystal orientation and to localize grain boundaries. The formation of oxidic nanotubes on Ti surfaces in dependence of the grain orientation was investigated, performed electrochemically by anodic oxidation from fluoride containing electrolyte.

Time-dependent analysis of the mixed-field orientation of molecules without rotational symmetry

NASA Astrophysics Data System (ADS)

Thesing, Linda V.; Küpper, Jochen; González-Férez, Rosario

2017-06-01

We present a theoretical study of the mixed-field orientation of molecules without rotational symmetry. The time-dependent one-dimensional and three-dimensional orientation of a thermal ensemble of 6-chloropyridazine-3-carbonitrile molecules in combined linearly or elliptically polarized laser fields and tilted dc electric fields is computed. The results are in good agreement with recent experimental results of one-dimensional orientation for weak dc electric fields [J. L. Hansen, J. Chem. Phys. 139, 234313 (2013)]. Moreover, they predict that using elliptically polarized laser fields or strong dc fields, three-dimensional orientation is obtained. The field-dressed dynamics of excited rotational states is characterized by highly non-adiabatic effects. We analyze the sources of these non-adiabatic effects and investigate their impact on the mixed-field orientation for different field configurations in mixed-field-orientation experiments.

Structural controls on Eocene to Pliocene tectonic and metallogenic evolution of the southernmost Lesser Caucasus, Armenia: paleostress field reconstruction and fault-slip analysis

NASA Astrophysics Data System (ADS)

Hovakimyan, Samvel; Moritz, Robert; Tayan, Rodrik

2017-04-01

The Cenozoic evolution of the central segment of the Tethyan belt is dominated by oblique convergence and final collision of Gondwana-derived terranes and the Arabian plate with Eurasia, which created a favorable setting for the formation of the highly mineralized Meghri-Ordubad pluton in the southernmost Lesser Caucasus. Regional strike-slip faults played an important role in the control of the porphyry Cu-Mo and epithermal systems hosted by the Meghri-Ordubad pluton. In this contribution we discuss the paleostress and the kinematic environment of the major strike-slip and oblique-slip ore-controlling faults throughout the Eocene subduction to Mio-Pliocene post-collisional tectonic evolution of the Meghri-Ordubad pluton based on detailed structural field mapping of the ore districts, stereonet compilation of ore-bearing fractures and vein orientations in the major porphyry and epithermal deposits, and the paleostress reconstructions. Paleostress reconstructions indicate that during the Eocene and Early Oligocene, the main paleostress axe orientations reveal a dominant NE-SW-oriented compression, which is compatible with the subduction geometry of the Neotethys along Eurasia. This tectonic setting was favorable for dextral displacements along the two major, regional NNW-oriented Khustup-Giratakh and Salvard-Ordubad strike-slip faults. This resulted in the formation of a NS-oriented transrotational basin, known as the Central magma and ore- controlling zone (Tayan, 1998). It caused a horizontal clockwise rotation of blocks. The EW-oriented faults separating the blocks formed as en-échelon antithetic faults (Voghji, Meghrasar, Bughakyar and Meghriget-Cav faults). The Central zone consists of a network of EW-oriented sinistral and NS-oriented subparallel strike-slip faults (Tashtun, Spetry, Tey, Meghriget and Terterasar faults). They are active since the Eocene and were reactivated during the entire tectonic evolution of the pluton, but with different behaviors. During the Eocene, dextral displacement along the NS-oriented strike-slip faults were favorable for the opening of NE-oriented en-échelon normal faults. The NS-oriented faults, in particular at their intersection with EW- and NE-oriented faults, were important ore-controlling structures for the emplacement of major porphyry Cu-Mo (Dastakert, Aygedzor and Agarak) and epithermal (Tey-Lichkvaz and Terterasar) deposits. In summary, we conclude that from the Eocene to the Oligocene the dominant structural system consisted essentially in dextral strike-slip tectonics along the major NS-oriented faults. During the Oligocene to Miocene, NS-oriented compression and EW-oriented extension predominated, which is consistent with the collisional and post-collisional geodynamic evolution of the study area. This setting resulted in renewed dextral displacement along the NS-oriented ore-controlling faults, and sinistral displacement along the EW-oriented antithetic faults. This setting created the favorable geometry for opening NS- EW- and NE-oriented extension fractures, and the adequate conditions for the emplacement of vein-, stockwork-type porphyry deposits, including the giant Kadjaran deposit. During the Lower Miocene to Pliocene there was a rotation in the main regional stress components according to progressive regional evolution. Paleostress reconstructions indicate a change in compression from NS during the Miocene to NNW during the Pliocene. The Tashtun transcurrent fault had an oblique-slip behavior. It formed a negative flower structure with a sinistral strike-slip component, which resulted in the development of a pull-apart basin and the formation of the Lichk porphyry-epithermal system.

George Herbert Mead, Curriculum Theorist: The Curriculum Field and the Problem of Social Control.

ERIC Educational Resources Information Center

Franklin, Barry M.

This paper is one of three presented at a symposium intended to suggest how historical studies of the curriculum field can aid in identifying alternative perspectives to the prevailing scientific-technical perspective, an orientation that has dominated the curriculum field since its inception as a formal area of study. This paper contends that…

Effect of resonant magnetic perturbations on three dimensional equilibria in the Madison Symmetric Torus reversed-field pinch

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

Munaretto, S., E-mail: smunaretto@wisc.edu; Chapman, B. E.; Nornberg, M. D.

2016-05-15

The orientation of 3D equilibria in the Madison Symmetric Torus (MST) [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] reversed-field pinch can now be controlled with a resonant magnetic perturbation (RMP). Absent the RMP, the orientation of the stationary 3D equilibrium varies from shot to shot in a semi-random manner, making its diagnosis difficult. Produced with a poloidal array of saddle coils at the vertical insulated cut in MST's thick conducting shell, an m = 1 RMP with an amplitude b{sub r}/B ∼ 10% forces the 3D structure into any desired orientation relative to MST's diagnostics. This control has led to improvedmore » diagnosis, revealing enhancements in both the central electron temperature and density. With sufficient amplitude, the RMP also inhibits the generation of high-energy (>20 keV) electrons, which otherwise emerge due to a reduction in magnetic stochasticity in the core. Field line tracing reveals that the RMP reintroduces stochasticity to the core. A m = 3 RMP of similar amplitude has little effect on the magnetic topology or the high-energy electrons.« less

A genetic switch controls the production of flagella and toxins in Clostridium difficile.

PubMed

Anjuwon-Foster, Brandon R; Tamayo, Rita

2017-03-01

In the human intestinal pathogen Clostridium difficile, flagella promote adherence to intestinal epithelial cells. Flagellar gene expression also indirectly impacts production of the glucosylating toxins, which are essential to diarrheal disease development. Thus, factors that regulate the expression of the flgB operon will likely impact toxin production in addition to flagellar motility. Here, we report the identification a "flagellar switch" that controls the phase variable production of flagella and glucosylating toxins. The flagellar switch, located upstream of the flgB operon containing the early stage flagellar genes, is a 154 bp invertible sequence flanked by 21 bp inverted repeats. Bacteria with the sequence in one orientation expressed flagellum and toxin genes, produced flagella, and secreted the toxins ("flg phase ON"). Bacteria with the sequence in the inverse orientation were attenuated for flagellar and toxin gene expression, were aflagellate, and showed decreased toxin secretion ("flg phase OFF"). The orientation of the flagellar switch is reversible during growth in vitro. We provide evidence that gene regulation via the flagellar switch occurs post-transcription initiation and requires a C. difficile-specific regulatory factor to destabilize or degrade the early flagellar gene mRNA when the flagellar switch is in the OFF orientation. Lastly, through mutagenesis and characterization of flagellar phase locked isolates, we determined that the tyrosine recombinase RecV, which catalyzes inversion at the cwpV switch, is also responsible for inversion at the flagellar switch in both directions. Phase variable flagellar motility and toxin production suggests that these important virulence factors have both advantageous and detrimental effects during the course of infection.

Three-Dimensional Stress Fields and Slip Systems for Single Crystal Superalloy Notched Specimens

NASA Technical Reports Server (NTRS)

Magnan, Shannon M.; Throckmorton, David (Technical Monitor)

2002-01-01

Single crystal superalloys have become increasingly popular for turbine blade and vane applications due to their high strength, and creep and fatigue resistance at elevated temperatures. The crystallographic orientation of a single crystal material greatly affects its material properties, including elastic modulus, shear modulus, and ductility. These directional properties, along with the type of loading and temperature, dictate an anisotropic response in the yield strength, creep resistance, creep rupture ductility, fatigue resistance, etc. A significant amount of research has been conducted to determine the material properties in the <001> orientation, yet the material properties deviating from the <001> orientation have not been assessed for all cases. Based on the desired application and design criteria, a crystal orientation is selected to yield the maximum properties. Currently, single crystal manufacturing is able to control the primary crystallographic orientation within 15 of the target orientation, which is an acceptable deviation to meet both performance and cost guidelines; the secondary orientation is rarely specified. A common experiment is the standard load-controlled tensile test, in which specimens with different orientations can be loaded to observe the material response. The deformation behavior of single-crystal materials under tension and compression is known to be a function of not only material orientation, but also of varying microdeformation (i.e. dislocation) mechanisms. The underlying dislocation motion causes deformation via slip, and affects the activation of specific slip systems based on load and orientation. The slip can be analyzed by observing the visible traces left on the surface of the specimen from the slip activity within the single crystal material. The goal of this thesis was to predict the slip systems activated in three-dimensional stress fields of a notched tensile specimen, as a function of crystal orientation, using finite element analysis without addressing microstructural deformation mechanisms that govern their activation. Out of three orientations tested, the specimen with a [110] load orientation and a [001] growth direction had the lowest maximum resolved shear stress; this specimen orientation appears to be the best design candidate for a tensile application.

Effect of lactation therapy on Staphylococcus aureus transmission dynamics in two commercial dairy herds

PubMed Central

2013-01-01

Background Treatment of subclinical mastitis during lactation can have both direct (individual animal level) and indirect (population level) effects. With a few exceptions, prior research has focused on evaluating the direct effects of mastitis treatment, and to date no controlled field trials have been conducted to test whether beneficial indirect effects of lactation treatment strategies targeting subclinical mastitis can be demonstrated on commercial dairy farms. Furthermore, there is limited knowledge on the impact of such interventions on the population dynamics of specific bacterial strains. The purpose of this study was to test the hypothesis that lactation therapy targeting S. aureus subclinical intramammary infection reduces transmission of S. aureus strains within dairy herds. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to determine strain specific infection dynamics in treated and control groups in a split herd trial conducted on 2 commercial dairy farms. Results The direct effect of 8 days intramammary lactation therapy with pirlimycin hydrochloride was demonstrated by an increased proportion of cure and a reduction in duration of infection in quarters receiving treatment compared to untreated controls. The indirect effect of lactation therapy was demonstrated by reduction of new S. aureus intramammary infections (IMI) caused by the dominant strain type in both herds. Strain typing of representative isolates taken over the duration of all IMI, including pre- and post-treatment isolates, provided more precise estimates of new infection, cure, and re-infection rates. New S. aureus infections in recovered susceptible quarters and the emergence of a new strain type in one herd influenced incidence measures. Conclusion In addition to demonstrating positive direct effects of lactation therapy, this study provides evidence that treatment of subclinical S. aureus mastitis during lactation can have indirect effects including preventing new IMI and reducing incidence of clinical mastitis within dairy herds. Strain specific transmission parameter estimates for S. aureus MLST clonal complexes 5, 97 and 705 in 2 commercial dairy herds are also reported. PMID:23398676

Effect of lactation therapy on Staphylococcus aureus transmission dynamics in two commercial dairy herds.

PubMed

Barlow, John W; Zadoks, Ruth N; Schukken, Ynte H

2013-02-11

Treatment of subclinical mastitis during lactation can have both direct (individual animal level) and indirect (population level) effects. With a few exceptions, prior research has focused on evaluating the direct effects of mastitis treatment, and to date no controlled field trials have been conducted to test whether beneficial indirect effects of lactation treatment strategies targeting subclinical mastitis can be demonstrated on commercial dairy farms. Furthermore, there is limited knowledge on the impact of such interventions on the population dynamics of specific bacterial strains. The purpose of this study was to test the hypothesis that lactation therapy targeting S. aureus subclinical intramammary infection reduces transmission of S. aureus strains within dairy herds. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to determine strain specific infection dynamics in treated and control groups in a split herd trial conducted on 2 commercial dairy farms. The direct effect of 8 days intramammary lactation therapy with pirlimycin hydrochloride was demonstrated by an increased proportion of cure and a reduction in duration of infection in quarters receiving treatment compared to untreated controls. The indirect effect of lactation therapy was demonstrated by reduction of new S. aureus intramammary infections (IMI) caused by the dominant strain type in both herds. Strain typing of representative isolates taken over the duration of all IMI, including pre- and post-treatment isolates, provided more precise estimates of new infection, cure, and re-infection rates. New S. aureus infections in recovered susceptible quarters and the emergence of a new strain type in one herd influenced incidence measures. In addition to demonstrating positive direct effects of lactation therapy, this study provides evidence that treatment of subclinical S. aureus mastitis during lactation can have indirect effects including preventing new IMI and reducing incidence of clinical mastitis within dairy herds. Strain specific transmission parameter estimates for S. aureus MLST clonal complexes 5, 97 and 705 in 2 commercial dairy herds are also reported.

Face inversion and acquired prosopagnosia reduce the size of the perceptual field of view.

PubMed

Van Belle, Goedele; Lefèvre, Philippe; Rossion, Bruno

2015-03-01

Using a gaze-contingent morphing approach, we asked human observers to choose one of two faces that best matched the identity of a target face: one face corresponded to the reference face's fixated part only (e.g., one eye), the other corresponded to the unfixated area of the reference face. The face corresponding to the fixated part was selected significantly more frequently in the inverted than in the upright orientation. This observation provides evidence that face inversion reduces an observer's perceptual field of view, even when both upright and inverted faces are displayed at full view and there is no performance difference between these conditions. It rules out an account of the drop of performance for inverted faces--one of the most robust effects in experimental psychology--in terms of a mere difference in local processing efficiency. A brain-damaged patient with pure prosopagnosia, viewing only upright faces, systematically selected the face corresponding to the fixated part, as if her perceptual field was reduced relative to normal observers. Altogether, these observations indicate that the absence of visual knowledge reduces the perceptual field of view, supporting an indirect view of visual perception. Copyright © 2014 Elsevier B.V. All rights reserved.

Magnetically-assembled micro/mesopixels exhibiting light intensity enhancement in the (012) planes of fish guanine crystals

NASA Astrophysics Data System (ADS)

Chikashige, T.; Iwasaka, M.

2018-05-01

In this study, a new method was investigated to form light-reflecting dots at the micrometer scale using the magnetic orientations of biogenic guanine crystals obtained from fish skin and scales. The crystal platelets, possessing average dimensions of 5 μm×20 μm×100 nm, were dispersed in water and observed during exposure to vertical magnetic fields up to 5 T. The magnetic field direction was parallel to Earth's gravity, and allowed the narrowest edges of the crystals to be observed at the micrometer scale for the first time. The magnetic orientation process was initiated under conditions where the crystal platelets in water were laid on a glass substrate or where the platelets had random orientations. In the former case, the crystal platelets followed a two-stage magnetic orientation process where, in the first step, the platelet widths were aligned in the magnetic field direction. The second step required rotation of the ˜20-μm-long plates with respect to the Earth's gravity, where application of a 5 T magnetic field enabled their orientation. Real-time images of the magnetically aligning platelets provided new evidence that the crystal platelets also emitted reflected light from a very narrow window at two crystal planes (i.e., (0 1 ¯ 2 ¯ ) and (0 1 ¯ 2 )). In the latter case with random platelet orientation, spatially-condensed light-reflecting dots appeared while the guanine crystal platelets were floating and maintaining their orientation. The technique developed for controlling light-reflecting microscale objects in an aqueous medium can be applied to produce a type of microfluidic optical tool.

Hybrid Adaptive Flight Control with Model Inversion Adaptation

NASA Technical Reports Server (NTRS)

Nguyen, Nhan

2011-01-01

This study investigates a hybrid adaptive flight control method as a design possibility for a flight control system that can enable an effective adaptation strategy to deal with off-nominal flight conditions. The hybrid adaptive control blends both direct and indirect adaptive control in a model inversion flight control architecture. The blending of both direct and indirect adaptive control provides a much more flexible and effective adaptive flight control architecture than that with either direct or indirect adaptive control alone. The indirect adaptive control is used to update the model inversion controller by an on-line parameter estimation of uncertain plant dynamics based on two methods. The first parameter estimation method is an indirect adaptive law based on the Lyapunov theory, and the second method is a recursive least-squares indirect adaptive law. The model inversion controller is therefore made to adapt to changes in the plant dynamics due to uncertainty. As a result, the modeling error is reduced that directly leads to a decrease in the tracking error. In conjunction with the indirect adaptive control that updates the model inversion controller, a direct adaptive control is implemented as an augmented command to further reduce any residual tracking error that is not entirely eliminated by the indirect adaptive control.

Calibration of Low Cost Digital Camera Using Data from Simultaneous LIDAR and Photogrammetric Surveys

NASA Astrophysics Data System (ADS)

Mitishita, E.; Debiasi, P.; Hainosz, F.; Centeno, J.

2012-07-01

Digital photogrammetric products from the integration of imagery and lidar datasets are a reality nowadays. When the imagery and lidar surveys are performed together and the camera is connected to the lidar system, a direct georeferencing can be applied to compute the exterior orientation parameters of the images. Direct georeferencing of the images requires accurate interior orientation parameters to perform photogrammetric application. Camera calibration is a procedure applied to compute the interior orientation parameters (IOPs). Calibration researches have established that to obtain accurate IOPs, the calibration must be performed with same or equal condition that the photogrammetric survey is done. This paper shows the methodology and experiments results from in situ self-calibration using a simultaneous images block and lidar dataset. The calibration results are analyzed and discussed. To perform this research a test field was fixed in an urban area. A set of signalized points was implanted on the test field to use as the check points or control points. The photogrammetric images and lidar dataset of the test field were taken simultaneously. Four strips of flight were used to obtain a cross layout. The strips were taken with opposite directions of flight (W-E, E-W, N-S and S-N). The Kodak DSC Pro SLR/c digital camera was connected to the lidar system. The coordinates of the exposition station were computed from the lidar trajectory. Different layouts of vertical control points were used in the calibration experiments. The experiments use vertical coordinates from precise differential GPS survey or computed by an interpolation procedure using the lidar dataset. The positions of the exposition stations are used as control points in the calibration procedure to eliminate the linear dependency of the group of interior and exterior orientation parameters. This linear dependency happens, in the calibration procedure, when the vertical images and flat test field are used. The mathematic correlation of the interior and exterior orientation parameters are analyzed and discussed. The accuracies of the calibration experiments are, as well, analyzed and discussed.

Visual field information in Nap-of-the-Earth flight by teleoperated Helmet-Mounted displays

NASA Technical Reports Server (NTRS)

Grunwald, Arthur J.; Kohn, S.; Merhav, S. J.

1991-01-01

The human ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays originates from a Forward Looking Infrared Radiation Camera, gimbal-mounted at the front of the aircraft and slaved to the pilot's line-of-sight, to obtain wide-angle visual coverage. Although these displays are proved to be effective in Apache and Cobra helicopter night operations, they demand very high pilot proficiency and work load. Experimental work presented in the paper has shown that part of the difficulties encountered in vehicular control by means of these displays can be attributed to the narrow viewing aperture and head/camera slaving system phase lags. Both these shortcomings will impair visuo-vestibular coordination, when voluntary head rotation is present. This might result in errors in estimating the Control-Oriented Visual Field Information vital in vehicular control, such as the vehicle yaw rate or the anticipated flight path, or might even lead to visuo-vestibular conflicts (motion sickness). Since, under these conditions, the pilot will tend to minimize head rotation, the full wide-angle coverage of the Helmet-Mounted Display, provided by the line-of-sight slaving system, is not always fully utilized.

Stress Analysis of Composite Cylindrical Shells with an Elliptical Cutout

NASA Technical Reports Server (NTRS)

Oterkus, E.; Madenci, E.; Nemeth, M. P.

2007-01-01

A special-purpose, semi-analytical solution method for determining the stress and deformation fields in a thin laminated-composite cylindrical shell with an elliptical cutout is presented. The analysis includes the effects of cutout size, shape, and orientation; non-uniform wall thickness; oval-cross-section eccentricity; and loading conditions. The loading conditions include uniform tension, uniform torsion, and pure bending. The analysis approach is based on the principle of stationary potential energy and uses Lagrange multipliers to relax the kinematic admissibility requirements on the displacement representations through the use of idealized elastic edge restraints. Specifying appropriate stiffness values for the elastic extensional and rotational edge restraints (springs) allows the imposition of the kinematic boundary conditions in an indirect manner, which enables the use of a broader set of functions for representing the displacement fields. Selected results of parametric studies are presented for several geometric parameters that demonstrate that analysis approach is a powerful means for developing design criteria for laminated-composite shells.

Stress Analysis of Composite Cylindrical Shells With an Elliptical Cutout

NASA Technical Reports Server (NTRS)

Nemeth, M. P.; Oterkus, E.; Madenci, E.

2005-01-01

A special-purpose, semi-analytical solution method for determining the stress and deformation fields in a thin laminated-composite cylindrical shell with an elliptical cutout is presented. The analysis includes the effects of cutout size, shape, and orientation; nonuniform wall thickness; oval-cross-section eccentricity; and loading conditions. The loading conditions include uniform tension, uniform torsion, and pure bending. The analysis approach is based on the principle of stationary potential energy and uses Lagrange multipliers to relax the kinematic admissibility requirements on the displacement representations through the use of idealized elastic edge restraints. Specifying appropriate stiffness values for the elastic extensional and rotational edge restraints (springs) allows the imposition of the kinematic boundary conditions in an indirect manner, which enables the use of a broader set of functions for representing the displacement fields. Selected results of parametric studies are presented for several geometric parameters that demonstrate that analysis approach is a powerful means for developing design criteria for laminated-composite shells.

Attosecond polarization control in atomic RABBITT-like experiments assisted by a circularly polarized laser

NASA Astrophysics Data System (ADS)

Boll, D. I. R.; Fojón, O. A.

2017-12-01

We study theoretically the single ionization of noble gas atoms by the combined action of an attosecond pulse train with linear polarization and an assistant laser field with circular polarization. We employ a non-perturbative model that under certain approximations gives closed-form expressions for the angular distributions of photoelectrons. Interestingly, our model allow us to interpret these angular distributions as two-centre interferences where the orientation and the modulus of the separation vector between the virtual emitters is governed by the assistant laser field. Additionally, we show that such a configuration of light fields is similar to the polarization control technique, where both the attosecond pulse train and the assistant laser field have linear polarizations whose relative orientation may be controlled. Moreover, in order to compare our results with the available experimental data, we obtain analytical expressions for the cross sections integrated over the photoelectron emission angles. By means of these expressions, we define the ‘magic time’ as the delay for which the total cross sections for atomic targets exhibit the same functional form as the one of the monochromatic photoionization of diatomic molecular targets.

Real medical benefit assessed by indirect comparison.

PubMed

Falissard, Bruno; Zylberman, Myriam; Cucherat, Michel; Izard, Valérie; Meyer, François

2009-01-01

Frequently, in data packages submitted for Marketing Approval to the CHMP, there is a lack of relevant head-to-head comparisons of medicinal products that could enable national authorities responsible for the approval of reimbursement to assess the Added Therapeutic Value (ASMR) of new clinical entities or line extensions of existing therapies.Indirect or mixed treatment comparisons (MTC) are methods stemming from the field of meta-analysis that have been designed to tackle this problem. Adjusted indirect comparisons, meta-regressions, mixed models, Bayesian network analyses pool results of randomised controlled trials (RCTs), enabling a quantitative synthesis.The REAL procedure, recently developed by the HAS (French National Authority for Health), is a mixture of an MTC and effect model based on expert opinions. It is intended to translate the efficacy observed in the trials into effectiveness expected in day-to-day clinical practice in France.

Method of using an electric field controlled emulsion phase contactor

DOEpatents

Scott, T.C.

1993-11-16

A system is described for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity. 5 figures.

Magnetic barriers and their q95 dependence at DIII-D

NASA Astrophysics Data System (ADS)

Volpe, F. A.; Kessler, J.; Ali, H.; Evans, T. E.; Punjabi, A.

2012-05-01

It is well known that externally generated resonant magnetic perturbations (RMPs) can form islands in the plasma edge. In turn, large overlapping islands generate stochastic fields, which are believed to play a role in the avoidance and suppression of edge localized modes (ELMs) at DIII-D. However, large coalescing islands can also generate, in the middle of these stochastic regions, KAM surfaces effectively acting as ‘barriers’ against field-line dispersion and, indirectly, particle diffusion. It was predicted in Ali and Punjabi (2007 Plasma Phys. Control. Fusion 49 1565-82) that such magnetic barriers can form in piecewise analytic DIII-D plasma equilibria. In this work, the formation of magnetic barriers at DIII-D is corroborated by field-line tracing calculations using experimentally constrained EFIT (Lao et al 1985 Nucl. Fusion 25 1611) DIII-D equilibria perturbed to include the vacuum field from the internal coils utilized in the experiments. According to these calculations, the occurrence and location of magnetic barriers depend on the edge safety factor q95. It was thus suggested that magnetic barriers might contribute to narrowing the edge stochastic layer and play an indirect role in the RMPs failing to control ELMs for certain values of q95. The analysis of DIII-D discharges where q95 was varied, however, does not show anti-correlation between barrier formation and ELM suppression.

Effects of agricultural practices on organic matter degradation in ditches

NASA Astrophysics Data System (ADS)

Hunting, Ellard R.; Vonk, J. Arie; Musters, C. J. M.; Kraak, Michiel H. S.; Vijver, Martina G.

2016-02-01

Agricultural practices can result in differences in organic matter (OM) and agricultural chemical inputs in adjacent ditches, but its indirect effects on OM composition and its inherent consequences for ecosystem functioning remain uncertain. This study determined the effect of agricultural practices (dairy farm grasslands and hyacinth bulb fields) on OM degradation by microorganisms and invertebrates with a consumption and food preference experiment in the field and in the laboratory using natural OM collected from the field. Freshly cut grass and hyacinths were also offered to control for OM composition and large- and small mesh-sizes were used to distinguish microbial decomposition and invertebrate consumption. Results show that OM decomposition by microorganisms and consumption by invertebrates was similar throughout the study area, but that OM collected from ditches adjacent grasslands and freshly cut grass and hyacinths were preferred over OM collected from ditches adjacent to a hyacinth bulb field. In the case of OM collected from ditches adjacent hyacinth bulb fields, both microbial decomposition and invertebrate consumption were strongly retarded, likely resulting from sorption and accumulation of pesticides. This outcome illustrates that differences in agricultural practices can, in addition to direct detrimental effects on aquatic organisms, indirectly alter the functioning of adjacent aquatic ecosystems.

Closed Loop Control of a Tethered Magnetic Capsule Endoscope

PubMed Central

Taddese, Addisu Z.; Slawinski, Piotr R.; Obstein, Keith L.; Valdastri, Pietro

2017-01-01

Magnetic field gradients have repeatedly been shown to be the most feasible mechanism for gastrointestinal capsule endoscope actuation. An inverse quartic magnetic force variation with distance results in large force gradients induced by small movements of a driving magnet; this necessitates robotic actuation of magnets to implement stable control of the device. A typical system consists of a serial robot with a permanent magnet at its end effector that actuates a capsule with an embedded permanent magnet. We present a tethered capsule system where a capsule with an embedded magnet is closed loop controlled in 2 degree-of-freedom in position and 2 degree-of-freedom in orientation. Capitalizing on the magnetic field of the external driving permanent magnet, the capsule is localized in 6-D allowing for both position and orientation feedback to be used in a control scheme. We developed a relationship between the serial robot's joint parameters and the magnetic force and torque that is exerted onto the capsule. Our methodology was validated both in a dynamic simulation environment where a custom plug-in for magnetic interaction was written, as well as on an experimental platform. The tethered capsule was demonstrated to follow desired trajectories in both position and orientation with accuracy that is acceptable for colonoscopy. PMID:28286886

Closed Loop Control of a Tethered Magnetic Capsule Endoscope.

PubMed

Taddese, Addisu Z; Slawinski, Piotr R; Obstein, Keith L; Valdastri, Pietro

2016-06-01

Magnetic field gradients have repeatedly been shown to be the most feasible mechanism for gastrointestinal capsule endoscope actuation. An inverse quartic magnetic force variation with distance results in large force gradients induced by small movements of a driving magnet; this necessitates robotic actuation of magnets to implement stable control of the device. A typical system consists of a serial robot with a permanent magnet at its end effector that actuates a capsule with an embedded permanent magnet. We present a tethered capsule system where a capsule with an embedded magnet is closed loop controlled in 2 degree-of-freedom in position and 2 degree-of-freedom in orientation. Capitalizing on the magnetic field of the external driving permanent magnet, the capsule is localized in 6-D allowing for both position and orientation feedback to be used in a control scheme. We developed a relationship between the serial robot's joint parameters and the magnetic force and torque that is exerted onto the capsule. Our methodology was validated both in a dynamic simulation environment where a custom plug-in for magnetic interaction was written, as well as on an experimental platform. The tethered capsule was demonstrated to follow desired trajectories in both position and orientation with accuracy that is acceptable for colonoscopy.

Composite Reinforcement by Magnetic Control of Fiber Density and Orientation.

PubMed

Goldberg, Omri; Greenfeld, Israel; Wagner, H Daniel

2018-05-08

The flexural rigidity of cylindrical specimens, composed of epoxy reinforced by short, magnetized glass fibers, was enhanced using weak magnetic fields (<100 mT). By spatially controlling the magnitude and direction of the field, and thereby the torques and forces acting locally on the fibers, the orientation and concentration of the fillers in the matrix could be tuned prior to curing. Unidirectional alignment of the fibers, achieved using an air-core solenoid, improved the contribution of the fibers to the flexure modulus by a factor of 3. When a ring-shaped permanent magnet was utilized, the glass fibers were migrated preferentially near the rod boundary, and as a result, the contribution of the fibers to the flexure modulus doubled. The fiber length, density, and orientation distributions were extracted by μCT image analysis, allowing comparison of the experimental flexure modulus to a modified rule of mixtures prediction. The ability to magnetically control the fiber distribution in reinforced composites demonstrated in this study may be applied in the fabrication of complex micro- and macroscale structures with spatially variable anisotropy, allowing features such as crack diversion, strengthening of highly loaded regions, as well as economic management of materials and weight.

New Technique of High-Performance Torque Control Developed for Induction Machines

NASA Technical Reports Server (NTRS)

Kenny, Barbara H.

2003-01-01

Two forms of high-performance torque control for motor drives have been described in the literature: field orientation control and direct torque control. Field orientation control has been the method of choice for previous NASA electromechanical actuator research efforts with induction motors. Direct torque control has the potential to offer some advantages over field orientation, including ease of implementation and faster response. However, the most common form of direct torque control is not suitable for the highspeed, low-stator-flux linkage induction machines designed for electromechanical actuators with the presently available sample rates of digital control systems (higher sample rates are required). In addition, this form of direct torque control is not suitable for the addition of a high-frequency carrier signal necessary for the "self-sensing" (sensorless) position estimation technique. This technique enables low- and zero-speed position sensorless operation of the machine. Sensorless operation is desirable to reduce the number of necessary feedback signals and transducers, thus improving the reliability and reducing the mass and volume of the system. This research was directed at developing an alternative form of direct torque control known as a "deadbeat," or inverse model, solution. This form uses pulse-width modulation of the voltage applied to the machine, thus reducing the necessary sample and switching frequency for the high-speed NASA motor. In addition, the structure of the deadbeat form allows the addition of the high-frequency carrier signal so that low- and zero-speed sensorless operation is possible. The new deadbeat solution is based on using the stator and rotor flux as state variables. This choice of state variables leads to a simple graphical representation of the solution as the intersection of a constant torque line with a constant stator flux circle. Previous solutions have been expressed only in complex mathematical terms without a method to clearly visualize the solution. The graphical technique allows a more insightful understanding of the operation of the machine under various conditions.

Controlled alignment of carbon nanofibers in a large-scale synthesis process

NASA Astrophysics Data System (ADS)

Merkulov, Vladimir I.; Melechko, A. V.; Guillorn, M. A.; Simpson, M. L.; Lowndes, D. H.; Whealton, J. H.; Raridon, R. J.

2002-06-01

Controlled alignment of catalytically grown carbon nanofibers (CNFs) at a variable angle to the substrate during a plasma-enhanced chemical vapor deposition process is achieved. The CNF alignment is controlled by the direction of the electric field lines during the synthesis process. Off normal CNF orientations are achieved by positioning the sample in the vicinity of geometrical features of the sample holder, where bending of the electric field lines occurs. The controlled growth of kinked CNFs that consist of two parts aligned at different angles to the substrate normal also is demonstrated.

Electric Field-Mediated Processing of Polymers. Appendix 1

NASA Technical Reports Server (NTRS)

Wnek, G. E.; Bowlin, G. L.; Haas, T. W.

2000-01-01

Significant opportunities exist for the processing of polymers (homopolymers and blends) using electric fields. We suggest that a broad range of properties can be achieved using a relatively small number of polymers, with electric fields providing the ability to tailor properties via the control of shape, morphology, and orientation. Specific attention is given to electrospinning, but we note that electroaerosol formation and field-modulated film casting represent additional processing options.

Microscopic vertical orientation of nano-interspaced graphene architectures in deposit films as electrodes for enhanced supercapacitor performance

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

Jang, Gyoung Gug; Song, Bo; Li, Liyi

This paper reported a novel two-step process to fabricate high-performance supercapacitor films that contain microscale domains of nano-interspaced, re-stacked graphene sheets oriented perpendicular to the surface of current collector substrate, i.e., carbon fiber paper. In the two-step process, we first used ligand molecules to modify the surface of graphene oxide (GO) sheets and manipulate the interspacing between the re-stacked GO sheets. The ligand-modified GOs, i.e., m-GOs, were then reduced to obtain more conductive graphene (m-rGO), where X-ray diffraction measurement results indicated well-controlled interlayer spacing between the restacked m-rGO sheets up to 1 nm. The typical lateral dimension of the restackedmore » m-rGO sheets were ~40 µm. Then, electrical field was introduced during m-rGO slurry deposition process to induce the vertical orientation of the m-rGO sheets/stacks in the film deposit. The direct current electrical field induced the orientation of the domains of m-rGO stacks along the direction perpendicular to the surface of deposit film, i.e., direction of electric field. Also, the applied electric field increased the interlayer spacing further, which should enhance the diffusion and accessibility of electrolyte ions. As compared with the traditionally deposited “control” films, the field-processed film deposits that contain oriented structure of graphene sheets/stacks have shown up to ~1.6 times higher values in capacitance (430 F/g at 0.5 A/g) and ~67% reduction in equivalent series resistance. Finally, the approach of using electric field to tailor the microscopic architecture of graphene-based deposit films is effective to fabricate film electrodes for high performance supercapacitors.« less

Microscopic vertical orientation of nano-interspaced graphene architectures in deposit films as electrodes for enhanced supercapacitor performance

DOE PAGES

Jang, Gyoung Gug; Song, Bo; Li, Liyi; ...

2016-12-14

This paper reported a novel two-step process to fabricate high-performance supercapacitor films that contain microscale domains of nano-interspaced, re-stacked graphene sheets oriented perpendicular to the surface of current collector substrate, i.e., carbon fiber paper. In the two-step process, we first used ligand molecules to modify the surface of graphene oxide (GO) sheets and manipulate the interspacing between the re-stacked GO sheets. The ligand-modified GOs, i.e., m-GOs, were then reduced to obtain more conductive graphene (m-rGO), where X-ray diffraction measurement results indicated well-controlled interlayer spacing between the restacked m-rGO sheets up to 1 nm. The typical lateral dimension of the restackedmore » m-rGO sheets were ~40 µm. Then, electrical field was introduced during m-rGO slurry deposition process to induce the vertical orientation of the m-rGO sheets/stacks in the film deposit. The direct current electrical field induced the orientation of the domains of m-rGO stacks along the direction perpendicular to the surface of deposit film, i.e., direction of electric field. Also, the applied electric field increased the interlayer spacing further, which should enhance the diffusion and accessibility of electrolyte ions. As compared with the traditionally deposited “control” films, the field-processed film deposits that contain oriented structure of graphene sheets/stacks have shown up to ~1.6 times higher values in capacitance (430 F/g at 0.5 A/g) and ~67% reduction in equivalent series resistance. Finally, the approach of using electric field to tailor the microscopic architecture of graphene-based deposit films is effective to fabricate film electrodes for high performance supercapacitors.« less

Theory of "laser distillation" of enantiomers: purification of a racemic mixture of randomly oriented dimethylallene in a collisional environment.

PubMed

Gerbasi, David; Shapiro, Moshe; Brumer, Paul

2006-02-21

Enantiomeric control of 1,3 dimethylallene in a collisional environment is examined. Specifically, our previous "laser distillation" scenario wherein three perpendicular linearly polarized light fields are applied to excite a set of vib-rotational eigenstates of a randomly oriented sample is considered. The addition of internal conversion, dissociation, decoherence, and collisional relaxation mimics experimental conditions and molecular decay processes. Of greatest relevance is internal conversion which, in the case of dimethylallene, is followed by molecular dissociation. For various rates of internal conversion, enantiomeric control is maintained in this scenario by a delicate balance between collisional relaxation of excited dimethylallene that enhances control and collisional dephasing, which diminishes control.

In Situ Electrochemical Synthesis of Oriented and Defect-Free AEL Molecular-Sieve Films Using Ionic Liquids.

PubMed

Yu, Tongwen; Chu, Wenling; Cai, Rui; Liu, Yanchun; Yang, Weishen

2015-10-26

Simply preparing oriented and defect-free molecular-sieve films have been a long-standing challenge both in academia and industry. Most of the early works focus on the careful and multiple controls of the seeds layer or synthesis conditions. Herein, we report a one-step in situ electrochemical ionothermal method that combines a controllable electric field with ionic liquids. We demonstrate that an in-plane oriented and defect-free AEL (one molecular-sieve framework type) molecular-sieve film was obtained using an Al electrode as the Al source. The excellent corrosion-resistant performance of the film makes this technology promising in multiple applications, such as anti-corrosion coatings. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Field-aligned current and auroral Hall current characteristics derived from the Swarm constellation

NASA Astrophysics Data System (ADS)

Huang, Tao; Wang, Hui; Hermann, Luehr

2017-04-01

On the basis of field-aligned currents (FACs) and Hall currents derived from high-resolution magnetic field data of the Swarm constellation the average characteristics of these two current systems in the auroral regions are comprehensively investigated by statistical methods. This is the first study considering both current types simultaneously and for both hemispheres. The FAC distribution, derived from the Swarm dual-spacecraft approach, reveals the well-known features of Region 1 (R1) and Region 2 (R2) FACs. At high latitudes, Region 0 (R0) FACs appear on the dayside. Their direction depends on the orientation of the interplanetary magnetic field (IMF) By component. Of particular interest is the distribution of auroral Hall currents. The most prominent auroral electrojets are found to be closely controlled by the solar wind input. But there is no dependence on the IMF By orientation. The eastward electrojet is about twice as strong in summer as in winter. Conversely, the westward electrojet shows less dependence on season. Part of the electrojet current is closed over the polar cap. Here the seasonal variation of conductivity mainly controls the current density. There is a clear channeling of return currents over the polar cap. Depending on IMF By orientation most of the current is flowing either on the dawn or dusk side. The direction of Hall currents in the noon sector depends directly on the orientation of the IMF By. This is true for both signs of the IMF Bz component. But largest differences between summer and winter seasons are found for northward IMF Bz. Around the midnight sector the westward substorm electrojet is dominating. As expected, it is highly dependent on magnetic activity, but shows only little response to the IMF By polarity.

The relationship of discrimination related to sexual orientation and HIV-relevant risk behaviors among men who have sex with men.

PubMed

Rogers, Andrew H; Jardin, Charles; Mayorga, Nubia A; Bakhshaie, Jafar; Leonard, Amy; Lemaire, Chad; Zvolensky, Michael J

2018-05-30

Men who have sex with men (MSM) are at high risk for contraction and transmission of Human Immunodeficiency Virus (HIV). Increased risk of infection has been linked to high risk behaviors, such as alcohol and drug use, as well as engaging in unsafe sexual behaviors. Experiences of discrimination related to sexual orientation often experienced in this population predict risky behavior outcomes, but little research has examined the mechanisms implicated in this model. The current study examined the effect of anxiety and depressive symptoms in the relationship between discrimination related to sexual orientation and high-risk behaviors of alcohol use, drug use, using sex to cope with negative emotions, frequency of sex without a condom, and frequency of sex with an HIV+ or unknown status partner. Three hundred and eighty-nine MSM were recruited to participate in a survey based study. Results indicated anxiety was maintained a significant indirect effect between discrimination related to sexual orientation and coping behaviors (using sex to cope, alcohol, substance use), but showed no significant indirect associations with risky sexual behavior. Overall, the current study provides novel empirical evidence that discrimination related to sexual orientation is associated with increased anxiety, which in turn, is associated with certain HIV risk behaviors. Importantly, it is possible that alcohol use, drug use, and using sex to cope with negative emotions may be precursors to more risky sexual behavior, such as engaging in anal sex without a condom or having sex with an HIV+ or unknown status partner. Clinically, reducing symptoms of anxiety in the context of discrimination related to sexual orientation may help reduce HIV risk behavior among MSM. Copyright © 2018. Published by Elsevier B.V.

Sensory signals and neuronal groups involved in guiding the sea-ward motor behavior in turtle hatchlings of Chelonia agassizi

NASA Astrophysics Data System (ADS)

Fuentes, A. L.; Camarena, V.; Ochoa, G.; Urrutia, J.; Gutierrez, G.

2007-05-01

Turtle hatchlings orient display sea-ward oriented movements as soon as they emerge from the nest. Although most studies have emphasized the role of the visual information in this process, less attention has been paid to other sensory modalities. Here, we evaluated the nature of sensory cues used by turtle hatchlings of Chelonia agassizi to orient their movements towards the ocean. We recorded the time they took to crawl from the nest to the beach front (120m long) in control conditions and in visually, olfactory and magnetically deprived circumstances. Visually-deprived hatchlings displayed a high degree of disorientation. Olfactory deprivation and magnetic field distortion impaired, but not abolished, sea-ward oriented movements. With regard to the neuronal mapping experiments, visual deprivation reduced dramatically c-fos expression in the whole brain. Hatchlings with their nares blocked revealed neurons with c-fos expression above control levels principally in the c and d areas, while those subjected to magnetic field distortion had a wide spread activation of neurons throughout the brain predominantly in the dorsal ventricular ridge The present results support that Chelonia agassizi hatchlings use predominantly visual cues to orient their movements towards the sea. Olfactory and magnetic cues may also be use but their influence on hatchlings oriented motor behavior is not as clear as it is for vision. This conclusion is supported by the fact that in the absence of olfactory and magnetic cues, the brain turns on the expression of c- fos in neuronal groups that, in the intact hatchling, are not normally involved in accomplishing the task.

Testing Direct and Indirect Effects of Identity, Media Use, Cognitions, and Conversations on Self-Reported Physical Activity Among a Sample of Hispanic Adults.

PubMed

Wirtz, John G; Wang, Zongyuan; Kulpavarapos, Supathida

2017-03-01

This article presents the results of a study testing the direct and indirect effects of identity, media use, cognitions and conversations on physical activity (PA). The study was guided by the O-S-O-R model (Markus & Zajonc, 1985), and it used data collected from a sample of Hispanic adults (N = 268) living in the U.S. Southwest. Exercise identity and ethnic identity were defined as pre-orientations (O 1 ); use of PA-related media content was defined as the stimulus (S); reflective integration and conversations about PA-related media were post-orientations (O 2 ); and self-reported physical activity was the behavioral response (R). Structural equation modeling was used to analyze the data, and several compelling results emerged. Exercise identity had a significant positive direct effect on PA and PA-related media use, as well as a significant positive indirect effect on conversations about PA-related media. PA-related media use exerted a strong and significant positive effect on conversations about PA-related media, as well as a significant positive indirect effect on PA. Finally, conversations about PA-related media content had a significant positive direct effect on PA. The results indicate that identity acts as a filter influencing what media content are selected and that cognitions and conversations about media content can serve as a link between media use and health behavior. Key words: O-S-O-R model, physical activity, Hispanic adults, identity, media use, conversation.

Observation of the asymmetric Bessel beams with arbitrary orientation using a digital micromirror device.

PubMed

Gong, Lei; Qiu, Xing-Ze; Ren, Yu-Xuan; Zhu, Hui-Qing; Liu, Wei-Wei; Zhou, Jin-Hua; Zhong, Min-Cheng; Chu, Xiu-Xiang; Li, Yin-Mei

2014-11-03

Recently, V. V. Kotlyar et al. [Opt. Lett.39, 2395 (2014)] have theoretically proposed a novel kind of three-parameter diffraction-free beam with a crescent profile, namely, the asymmetric Bessel (aB) beam. The asymmetry degree of such nonparaxial modes was shown to depend on a nonnegative real parameter c. We present a more generalized asymmetric Bessel mode in which the parameter c is a complex constant. This parameter controls not only the asymmetry degree of the mode but also the orientation of the optical crescent, and affects the energy distribution and orbital angular momentum (OAM) of the beam. As a proof of concept, the high-quality generation of asymmetric Bessel-Gauss beams was demonstrated with the super-pixel method using a digital micromirror device (DMD). We investigated the near-field properties as well as the far field features of such beams, and the experimental observations were in good agreement with the theoretical predictions. Additionally, we provided an effective way to control the beam's asymmetry and orientation, which may find potential applications in light-sheet microscopy and optical manipulation.

Perchlorate Removal, Destruction, and Field Monitoring Demonstration

DTIC Science & Technology

2006-10-02

ion exchange unit. A pulsation dampener minimized pressure and flow fluctuations in the ion exchange system and a flow totalizer monitored total...instrumentation and controls, piping , electrical services, site work, service facilities, engineering, construction expenses, and other indirect costs were... Piping 113,750 157,500 Electrical services 48,750 67,500 Site work 65,000 90,000

Magnetic Alignment of Block Copolymer Microdomains by Intrinsic Chain Anisotropy.

PubMed

Rokhlenko, Yekaterina; Gopinadhan, Manesh; Osuji, Chinedum O; Zhang, Kai; O'Hern, Corey S; Larson, Steven R; Gopalan, Padma; Majewski, Paweł W; Yager, Kevin G

2015-12-18

We examine the role of intrinsic chain susceptibility anisotropy in magnetic field directed self-assembly of a block copolymer using in situ x-ray scattering. Alignment of a lamellar mesophase is observed on cooling across the disorder-order transition with the resulting orientational order inversely proportional to the cooling rate. We discuss the origin of the susceptibility anisotropy, Δχ, that drives alignment and calculate its magnitude using coarse-grained molecular dynamics to sample conformations of surface-tethered chains, finding Δχ≈2×10^{-8}. From field-dependent scattering data, we estimate that grains of ≈1.2  μm are present during alignment. These results demonstrate that intrinsic anisotropy is sufficient to support strong field-induced mesophase alignment and suggest a versatile strategy for field control of orientational order in block copolymers.

Optimizing Global Coronal Magnetic Field Models Using Image-Based Constraints

NASA Technical Reports Server (NTRS)

Jones-Mecholsky, Shaela I.; Davila, Joseph M.; Uritskiy, Vadim

2016-01-01

The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in the heliosphere. It provides energy for coronal heating, controls the release of coronal mass ejections, and drives heliospheric and magnetospheric activity, yet the coronal magnetic field itself has proven difficult to measure. This difficulty has prompted a decades-long effort to develop accurate, timely, models of the field, an effort that continues today. We have developed a method for improving global coronal magnetic field models by incorporating the type of morphological constraints that could be derived from coronal images. Here we report promising initial tests of this approach on two theoretical problems, and discuss opportunities for application.

Neural field model to reconcile structure with function in primary visual cortex.

PubMed

Rankin, James; Chavane, Frédéric

2017-10-01

Voltage-sensitive dye imaging experiments in primary visual cortex (V1) have shown that local, oriented visual stimuli elicit stable orientation-selective activation within the stimulus retinotopic footprint. The cortical activation dynamically extends far beyond the retinotopic footprint, but the peripheral spread stays non-selective-a surprising finding given a number of anatomo-functional studies showing the orientation specificity of long-range connections. Here we use a computational model to investigate this apparent discrepancy by studying the expected population response using known published anatomical constraints. The dynamics of input-driven localized states were simulated in a planar neural field model with multiple sub-populations encoding orientation. The realistic connectivity profile has parameters controlling the clustering of long-range connections and their orientation bias. We found substantial overlap between the anatomically relevant parameter range and a steep decay in orientation selective activation that is consistent with the imaging experiments. In this way our study reconciles the reported orientation bias of long-range connections with the functional expression of orientation selective neural activity. Our results demonstrate this sharp decay is contingent on three factors, that long-range connections are sufficiently diffuse, that the orientation bias of these connections is in an intermediate range (consistent with anatomy) and that excitation is sufficiently balanced by inhibition. Conversely, our modelling results predict that, for reduced inhibition strength, spurious orientation selective activation could be generated through long-range lateral connections. Furthermore, if the orientation bias of lateral connections is very strong, or if inhibition is particularly weak, the network operates close to an instability leading to unbounded cortical activation.

Solution-processed, Self-organized Organic Single Crystal Arrays with Controlled Crystal Orientation

PubMed Central

Kumatani, Akichika; Liu, Chuan; Li, Yun; Darmawan, Peter; Takimiya, Kazuo; Minari, Takeo; Tsukagoshi, Kazuhito

2012-01-01

A facile solution process for the fabrication of organic single crystal semiconductor devices which meets the demand for low-cost and large-area fabrication of high performance electronic devices is demonstrated. In this paper, we develop a bottom-up method which enables direct formation of organic semiconductor single crystals at selected locations with desired orientations. Here oriented growth of one-dimensional organic crystals is achieved by using self-assembly of organic molecules as the driving force to align these crystals in patterned regions. Based upon the self-organized organic single crystals, we fabricate organic field effect transistor arrays which exhibit an average field-effect mobility of 1.1 cm2V−1s−1. This method can be carried out under ambient atmosphere at room temperature, thus particularly promising for production of future plastic electronics. PMID:22563523

A genetic switch controls the production of flagella and toxins in Clostridium difficile

PubMed Central

2017-01-01

In the human intestinal pathogen Clostridium difficile, flagella promote adherence to intestinal epithelial cells. Flagellar gene expression also indirectly impacts production of the glucosylating toxins, which are essential to diarrheal disease development. Thus, factors that regulate the expression of the flgB operon will likely impact toxin production in addition to flagellar motility. Here, we report the identification a “flagellar switch” that controls the phase variable production of flagella and glucosylating toxins. The flagellar switch, located upstream of the flgB operon containing the early stage flagellar genes, is a 154 bp invertible sequence flanked by 21 bp inverted repeats. Bacteria with the sequence in one orientation expressed flagellum and toxin genes, produced flagella, and secreted the toxins (“flg phase ON”). Bacteria with the sequence in the inverse orientation were attenuated for flagellar and toxin gene expression, were aflagellate, and showed decreased toxin secretion (“flg phase OFF”). The orientation of the flagellar switch is reversible during growth in vitro. We provide evidence that gene regulation via the flagellar switch occurs post-transcription initiation and requires a C. difficile-specific regulatory factor to destabilize or degrade the early flagellar gene mRNA when the flagellar switch is in the OFF orientation. Lastly, through mutagenesis and characterization of flagellar phase locked isolates, we determined that the tyrosine recombinase RecV, which catalyzes inversion at the cwpV switch, is also responsible for inversion at the flagellar switch in both directions. Phase variable flagellar motility and toxin production suggests that these important virulence factors have both advantageous and detrimental effects during the course of infection. PMID:28346491

Voltage-Controllable Colossal Magnetocrystalline Anisotropy in Single Layer Dichalcogenides

NASA Astrophysics Data System (ADS)

Sui, Xuelei; Hu, Tao; Wang, Jianfeng; Gu, Bing-Lin; Duan, Wenhui; Miao, Mao-Sheng

Materials with large magnetocrystalline anisotropy and strong electric field effects are in great need for new types of memory devices that are based on electric field control of spin orientations. Instead of using modified transition metal films, we propose that some monolayer transition metal dichalcogenides are ideal candidate materials for this purpose. Using density functional calculations, we illustrate that they exhibit not only exceedingly large magnetocrystalline anisotropy (MCA) but also colossal voltage modulation under external field. Especially, spins in some materials like CrSe2 and FeSe2, which is strongly preferred to in-plane orientation, can be totally switched to out-of-plane direction. The effect is attributed to the large band character alteration of transition metal d-states around the Fermi level by electric field. We further demonstrate that strain can also greatly change MCA, and can help to improve the modulation efficiency while combining with electric field. Acknowledge the support of the Ministry of Science and Technology of China (Grant No.2016YFA0301001), and the National Natural Science Foundation of China (Grants No. 11674188 and 11334006), NSF-funded XSEDE resources (TG-DMR130005) especially on Stampede.

On the Factors Determining the Eruptive Character of Solar Flares

NASA Astrophysics Data System (ADS)

Baumgartner, Christian; Thalmann, Julia K.; Veronig, Astrid M.

2018-02-01

We investigated how the magnetic field in solar active regions (ARs) controls flare activity, i.e., whether a confined or eruptive flare occurs. We analyzed 44 flares of GOES class M5.0 and larger that occurred during 2011–2015. We used 3D potential magnetic field models to study their location (using the flare distance from the flux-weighted AR center d FC) and the strength of the magnetic field in the corona above (via decay index n and flux ratio). We also present a first systematic study of the orientation of the coronal magnetic field, using the orientation φ of the flare-relevant polarity inversion line as a measure. We analyzed all quantities with respect to the size of the underlying dipole field, characterized by the distance between the opposite-polarity centers, d PC. Flares originating from underneath the AR dipole (d FC/d PC < 0.5) tend to be eruptive if launched from compact ARs (d PC ≤ 60 Mm) and confined if launched from extended ARs. Flares ejected from the periphery of ARs (d FC/d PC > 0.5) are predominantly eruptive. In confined events, the flare-relevant field adjusts its orientation quickly to that of the underlying dipole with height (Δφ ≳ 40° until the apex of the dipole field), in contrast to eruptive events where it changes more slowly with height. The critical height for torus instability, h crit = h(n = 1.5), discriminates best between confined (h crit ≳ 40 Mm) and eruptive flares (h crit ≲ 40 Mm). It discriminates better than Δφ, implying that the decay of the confining field plays a stronger role than its orientation at different heights.

Chinese American Parents’ Acculturation and Enculturation, Bicultural Management Difficulty, Depressive Symptoms, and Parenting

PubMed Central

Kim, Su Yeong; Shen, Yishan; Huang, Xuan; Wang, Yijie; Orozco-Lapray, Diana

2014-01-01

This study examined whether Chinese American parents’ acculturation and enculturation were related to parenting practices (punitive parenting, democratic child participation, and inductive reasoning) indirectly through the mediation of parents’ bicultural management difficulty and parental depressed mood. Data came from a two-wave study of Chinese American families in Northern California. Mothers and fathers were assessed when their children were in early adolescence and then again in middle adolescence (407 mothers and 381 fathers at Wave 1; 308 mothers and 281 fathers at Wave 2). For both waves, we examined cross-sectional models encompassing both direct and indirect links from parental cultural orientations to parenting practices. We also used individual fixed-effects techniques to account for selection bias in testing model relationships at Wave 2. At Wave 1, via bicultural management difficulty and depressive symptoms, American orientation was related to less punitive parenting and more inductive reasoning for both parents, and Chinese orientation was related to more punitive parenting and less inductive reasoning for fathers. The findings indicate that bicultural management difficulty and parental depressed mood are important mechanisms to be considered when studying the relation between Chinese American parents’ acculturation/enculturation and parenting. PMID:25678944

Conjugate field approaches for active array compensation

NASA Technical Reports Server (NTRS)

Acosta, R. J.

1989-01-01

Two approaches for calculating the compensating feed array complex excitations are namely, the indirect conjugate field matching (ICFM) and the direct conjugate field matching (DCFM) approach. In the ICFM approach the compensating feed array excitations are determined by considering the transmitting mode and the reciprocity principle. The DCF, in contrast calculates the array excitations by integrating directly the induced surface currents on the reflector under a receiving mode. DCFM allows the reflector to be illuminated by an incident plane wave with a tapered amplitude. The level of taper can effectively control the sidelobe level of the compensated antenna pattern. Both approaches are examined briefly.

"On solid ground": family and school connectedness promotes adolescents' future orientation.

PubMed

Crespo, Carla; Jose, Paul E; Kielpikowski, Magdalena; Pryor, Jan

2013-10-01

The present study investigated the role of connectedness to the family and school contexts on future orientation of New Zealand adolescents. Participants were 1774 young people (51.9% female) aged between 9 and 16 years at time 1 of the study, who reported their connectedness to family and school and their perceptions of future orientation at three times of measurement one year apart. Structural equation modelling was used to test the combined role of family and school connectedness on future orientation over time. Findings supported a multiple mediation model in that adolescents' connectedness to family and school predicted more positive perceptions of future orientation both directly and indirectly via the effect of the context variables on each other. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

2011 Quantum Control of Light & Matter Gordon Research Conference (July 31-August 5, 2011, Mount Holyoke College, South Hadley, MA)

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

Thomas Weinacht

2011-08-05

Quantum control of light and matter is the quest to steer a physical process to a desirable outcome, employing constructive and destructive interference. Three basic questions address feasibility of quantum control: (1) The problem of controllability, does a control field exist for a preset initial and target state; (2) Synthesis, constructively finding the field that leads to the target; and (3) Optimal Control Theory - optimizing the field that carries out this task. These continue to be the fundamental theoretical questions to be addressed in the conference. How to realize control fields in the laboratory is an ongoing challenge. Thismore » task is very diverse viewing the emergence of control scenarios ranging from attoseconds to microseconds. How do the experimental observations reflect on the theoretical framework? The typical arena of quantum control is an open environment where much of the control is indirect. How are control scenarios realized in dissipative open systems? Can new control opportunities emerge? Can one null decoherence effects? An ideal setting for control is ultracold matter. The initial and final state can be defined more precisely. Coherent control unifies many fields of physical science. A lesson learned in one field can reflect on another. Currently quantum information processing has emerged as a primary target of control where the key issue is controlling quantum gate operation. Modern nonlinear spectroscopy has emerged as another primary field. The challenge is to unravel the dynamics of molecular systems undergoing strong interactions with the environment. Quantum optics where non-classical fields are to be generated and employed. Finally, coherent control is the basis for quantum engineering. These issues will be under the limelight of the Gordon conference on Quantum Control of Light and Matter.« less

Multi-field electron emission pattern of 2D emitter: Illustrated with graphene

NASA Astrophysics Data System (ADS)

Luo, Ma; Li, Zhibing

2016-11-01

The mechanism of laser-assisted multi-field electron emission of two-dimensional emitters is investigated theoretically. The process is basically a cold field electron emission but having more controllable components: a uniform electric field controls the emission potential barrier, a magnetic field controls the quantum states of the emitter, while an optical field controls electron populations of specified quantum states. It provides a highly orientational vacuum electron line source whose divergence angle over the beam plane is inversely proportional to square root of the emitter height. Calculations are carried out for graphene with the armchair emission edge, as a concrete example. The rate equation incorporating the optical excitation, phonon scattering, and thermal relaxation is solved in the quasi-equilibrium approximation for electron population in the bands. The far-field emission patterns, that inherit the features of the Landau bands, are obtained. It is found that the optical field generates a characteristic structure at one wing of the emission pattern.

Control of unidirectional transport of single-file water molecules through carbon nanotubes in an electric field.

PubMed

Su, Jiaye; Guo, Hongxia

2011-01-25

The transport of water molecules through nanopores is not only crucial to biological activities but also useful for designing novel nanofluidic devices. Despite considerable effort and progress that has been made, a controllable and unidirectional water flow is still difficult to achieve and the underlying mechanism is far from being understood. In this paper, using molecular dynamics simulations, we systematically investigate the effects of an external electric field on the transport of single-file water molecules through a carbon nanotube (CNT). We find that the orientation of water molecules inside the CNT can be well-tuned by the electric field and is strongly coupled to the water flux. This orientation-induced water flux is energetically due to the asymmetrical water-water interaction along the CNT axis. The wavelike water density profiles are disturbed under strong field strengths. The frequency of flipping for the water dipoles will decrease as the field strength is increased, and the flipping events vanish completely for the relatively large field strengths. Most importantly, a critical field strength E(c) related to the water flux is found. The water flux is increased as E is increased for E ≤ E(c), while it is almost unchanged for E > E(c). Thus, the electric field offers a level of governing for unidirectional water flow, which may have some biological applications and provides a route for designing efficient nanopumps.

Hanle model of a spin-orbit coupled Bose-Einstein condensate of excitons in semiconductor quantum wells

NASA Astrophysics Data System (ADS)

Andreev, S. V.; Nalitov, A. V.

2018-04-01

We present a theoretical model of a driven-dissipative spin-orbit coupled Bose-Einstein condensate of indirect excitons in semiconductor quantum wells (QW's). Our steady-state solution of the problem shares analogies with the Hanle effect in an optical orientation experiment. The role of the spin pump in our case is played by Bose-stimulated scattering into a linearly-polarized ground state and the depolarization occurs as a result of exchange interaction between electrons and holes. Our theory agrees with the recent experiment [A. A. High et al., Phys. Rev. Lett. 110, 246403 (2013), 10.1103/PhysRevLett.110.246403], where spontaneous emergence of spatial coherence and polarization textures have been observed. As a complementary test, we discuss a configuration where an external magnetic field is applied in the structure plane.

Circular-polarization-sensitive metamaterial based on triple-quantum-dot molecules.

PubMed

Kotetes, Panagiotis; Jin, Pei-Qing; Marthaler, Michael; Schön, Gerd

2014-12-05

We propose a new type of chiral metamaterial based on an ensemble of artificial molecules formed by three identical quantum dots in a triangular arrangement. A static magnetic field oriented perpendicular to the plane breaks mirror symmetry, rendering the molecules sensitive to the circular polarization of light. By varying the orientation and magnitude of the magnetic field one can control the polarization and frequency of the emission spectrum. We identify a threshold frequency Ω, above which we find strong birefringence. In addition, Kerr rotation and circular-polarized lasing action can be implemented. We investigate the single-molecule lasing properties for different energy-level arrangements and demonstrate the possibility of circular-polarization conversion. Finally, we analyze the effect of weak stray electric fields or deviations from the equilateral triangular geometry.

Fraternal Birth Order and Extreme Right-Handedness as Predictors of Sexual Orientation and Gender Nonconformity in Men.

PubMed

Kishida, Mariana; Rahman, Qazi

2015-07-01

The present study explored whether there were relationships between number of older brothers, handedness, recalled childhood gender nonconformity (CGN), and sexual orientation in men. We used data from previous British studies conducted in our laboratory (N = 1,011 heterosexual men and 921 gay men). These men had completed measures of demographic variables, number and sex of siblings, CGN, and the Edinburgh Handedness Inventory. The results did not replicate the fraternal birth order effect. However, gay men had fewer "other siblings" than heterosexual men (even after controlling for the stopping-rule and family size). In a sub-sample (425 gay men and 478 heterosexual men) with data available on both sibling sex composition and handedness scores, gay men were found to show a significantly greater likelihood of extreme right-handedness and non-right-handedness compared to heterosexual men. There were no significant effects of sibling sex composition in this sub-sample. In a further sub-sample (N = 487) with data available on sibling sex composition, handedness, and CGN, we found that men with feminine scores on CGN were more extremely right-handed and had fewer other-siblings compared to masculine scoring men. Mediation analysis revealed that handedness was associated with sexual orientation directly and also indirectly through the mediating factor of CGN. We were unable to replicate the fraternal birth order effect in our archived dataset but there was evidence for a relationship among handedness, sexual orientation, and CGN. These data help narrow down the number of possible neurodevelopmental pathways leading to variations in male sexual orientation.

The Role of Attachment Style in Facebook Use and Social Capital: Evidence from University Students and a National Sample

PubMed Central

2015-01-01

Abstract Social networking sites (SNSs) can be beneficial tools for users to gain social capital. Although social capital consists of emotional and informational resources accumulated through interactions with strong or weak social network ties, the existing literature largely ignores attachment style in this context. This study employed attachment theory to explore individuals' attachment orientations toward Facebook usage and toward online and offline social capital. A university student sample (study 1) and a representative national sample (study 2) showed consistent results. Secure attachment was positively associated with online bonding and bridging capital and offline bridging capital. Additionally, secure attachment had an indirect effect on all capital through Facebook time. Avoidant attachment was negatively associated with online bonding capital. Anxious–ambivalent attachment had a direct association with online bonding capital and an indirect effect on all capital through Facebook. Interaction frequency with good friends on Facebook positively predicted all online and offline capital, whereas interaction frequency with average friends on Facebook positively predicted online bridging capital. Interaction frequency with acquaintances on Facebook was negatively associated with offline bonding capital. The study concludes that attachment style is a significant factor in guiding social orientation toward Facebook connections with different ties and influences online social capital. The study extends attachment theory among university students to a national sample to provide more generalizable evidence for the current literature. Additionally, this study extends attachment theory to the SNS setting with a nuanced examination of types of Facebook friends after controlling extraversion. Implications for future research are discussed. PMID:25751049

The role of attachment style in Facebook use and social capital: evidence from university students and a national sample.

PubMed

Lin, Jih-Hsuan

2015-03-01

Social networking sites (SNSs) can be beneficial tools for users to gain social capital. Although social capital consists of emotional and informational resources accumulated through interactions with strong or weak social network ties, the existing literature largely ignores attachment style in this context. This study employed attachment theory to explore individuals' attachment orientations toward Facebook usage and toward online and offline social capital. A university student sample (study 1) and a representative national sample (study 2) showed consistent results. Secure attachment was positively associated with online bonding and bridging capital and offline bridging capital. Additionally, secure attachment had an indirect effect on all capital through Facebook time. Avoidant attachment was negatively associated with online bonding capital. Anxious-ambivalent attachment had a direct association with online bonding capital and an indirect effect on all capital through Facebook. Interaction frequency with good friends on Facebook positively predicted all online and offline capital, whereas interaction frequency with average friends on Facebook positively predicted online bridging capital. Interaction frequency with acquaintances on Facebook was negatively associated with offline bonding capital. The study concludes that attachment style is a significant factor in guiding social orientation toward Facebook connections with different ties and influences online social capital. The study extends attachment theory among university students to a national sample to provide more generalizable evidence for the current literature. Additionally, this study extends attachment theory to the SNS setting with a nuanced examination of types of Facebook friends after controlling extraversion. Implications for future research are discussed.

Magnetic alignment of block copolymer microdomains by intrinsic chain anisotropy

DOE PAGES

Rokhlenko, Yekaterina; Yager, Kevin G.; Gopinadhan, Manesh; ...

2015-12-18

We examine the role of intrinsic chain susceptibility anisotropy in magnetic field directed self-assembly of a block copolymer using in situ x-ray scattering. Alignment of a lamellar mesophase is observed on cooling across the disorder-order transition with the resulting orientational order inversely proportional to the cooling rate. We discuss the origin of the susceptibility anisotropy, Δ χ, that drives alignment and calculate its magnitude using coarse-grained molecular dynamics to sample conformations of surface-tethered chains, finding Δ χ ≈ 2×10 –8. From field-dependent scattering data, we estimate that grains of ≈ 1.2 μm are present during alignment. Furthermore, these results demonstratemore » that intrinsic anisotropy is sufficient to support strong field-induced mesophase alignment and suggest a versatile strategy for field control of orientational order in block copolymers.« less

Alternating Magnetic Field Forces for Satellite Formation Flying

NASA Technical Reports Server (NTRS)

Youngquist, Robert C.; Nurge, Mark A.; Starr, Stnaley O.

2012-01-01

Selected future space missions, such as large aperture telescopes and multi-component interferometers, will require the precise positioning of a number of isolated satellites, yet many of the suggested approaches for providing satellites positioning forces have serious limitations. In this paper we propose a new approach, capable of providing both position and orientation forces, that resolves or alleviates many of these problems. We show that by using alternating fields and currents that finely-controlled forces can be induced on the satellites, which can be individually selected through frequency allocation. We also show, through analysis and experiment, that near field operation is feasible and can provide sufficient force and the necessary degrees of freedom to accurately position and orient small satellites relative to one another. In particular, the case of a telescope with a large number of free mirrors is developed to provide an example of the concept. We. also discuss the far field extension of this concept.

Methods for controlling pore morphology in aerogels using electric fields and products thereof

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

Worsley, Marcus A.; Baumann, Theodore F.; Satcher, Jr., Joe H.

In one embodiment, an aerogel or xerogel includes column structures of a material having minor pores therein and major pores devoid of the material positioned between the column structures, where longitudinal axes of the major pores are substantially parallel to one another. In another embodiment, a method includes heating a sol including aerogel or xerogel precursor materials to cause gelation thereof to form an aerogel or xerogel and exposing the heated sol to an electric field, wherein the electric field causes orientation of a microstructure of the sol during gelation, which is retained by the aerogel or xerogel. In onemore » approach, an aerogel has elongated pores extending between a material arranged in column structures having structural characteristics of being formed from a sol exposed to an electric field that causes orientation of a microstructure of the sol during gelation which is retained by the elongated pores of the aerogel.« less

System and method for manipulating domain pinning and reversal in ferromagnetic materials

DOEpatents

Silevitch, Daniel M.; Rosenbaum, Thomas F.; Aeppli, Gabriel

2013-10-15

A method for manipulating domain pinning and reversal in a ferromagnetic material comprises applying an external magnetic field to a uniaxial ferromagnetic material comprising a plurality of magnetic domains, where each domain has an easy axis oriented along a predetermined direction. The external magnetic field is applied transverse to the predetermined direction and at a predetermined temperature. The strength of the magnetic field is varied at the predetermined temperature, thereby isothermally regulating pinning of the domains. A magnetic storage device for controlling domain dynamics includes a magnetic hard disk comprising a uniaxial ferromagnetic material, a magnetic recording head including a first magnet, and a second magnet. The ferromagnetic material includes a plurality of magnetic domains each having an easy axis oriented along a predetermined direction. The second magnet is positioned adjacent to the magnetic hard disk and is configured to apply a magnetic field transverse to the predetermined direction.

Magnetic alignment of block copolymer microdomains by intrinsic chain anisotropy

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

Rokhlenko, Yekaterina; Yager, Kevin G.; Gopinadhan, Manesh

We examine the role of intrinsic chain susceptibility anisotropy in magnetic field directed self-assembly of a block copolymer using in situ x-ray scattering. Alignment of a lamellar mesophase is observed on cooling across the disorder-order transition with the resulting orientational order inversely proportional to the cooling rate. We discuss the origin of the susceptibility anisotropy, Δ χ, that drives alignment and calculate its magnitude using coarse-grained molecular dynamics to sample conformations of surface-tethered chains, finding Δ χ ≈ 2×10 –8. From field-dependent scattering data, we estimate that grains of ≈ 1.2 μm are present during alignment. Furthermore, these results demonstratemore » that intrinsic anisotropy is sufficient to support strong field-induced mesophase alignment and suggest a versatile strategy for field control of orientational order in block copolymers.« less

A control-oriented dynamic wind farm flow model: “WFSim”

NASA Astrophysics Data System (ADS)

Boersma, S.; Gebraad, P. M. O.; Vali, M.; Doekemeijer, B. M.; van Wingerden, J. W.

2016-09-01

In this paper, we present and extend the dynamic medium fidelity control-oriented Wind Farm Simulator (WFSim) model. WFSim resolves flow fields in wind farms in a horizontal, two dimensional plane. It is based on the spatially and temporally discretised two dimensional Navier-Stokes equations and the continuity equation and solves for a predefined grid and wind farm topology. The force on the flow field generated by turbines is modelled using actuator disk theory. Sparsity in system matrices is exploited in WFSim, which enables a relatively fast flow field computation. The extensions to WFSim we present in this paper are the inclusion of a wake redirection model, a turbulence model and a linearisation of the nonlinear WFSim model equations. The first is important because it allows us to carry out wake redirection control and simulate situations with an inflow that is misaligned with the rotor plane. The wake redirection model is validated against a theoretical wake centreline known from literature. The second extension makes WFSim more realistic because it accounts for wake recovery. The amount of recovery is validated using a high fidelity simulation model Simulator fOr Wind Farm Applications (SOWFA) for a two turbine test case. Finally, a linearisation is important since it allows the application of more standard analysis, observer and control techniques.

Electrostatic orientation of the electron-transfer complex between plastocyanin and cytochrome c.

PubMed

Roberts, V A; Freeman, H C; Olson, A J; Tainer, J A; Getzoff, E D

1991-07-15

To understand the specificity and efficiency of protein-protein interactions promoting electron transfer, we evaluated the role of electrostatic forces in precollision orientation by the development of two new methods, computer graphics alignment of protein electrostatic fields and a systematic orientational search of intermolecular electrostatic energies for two proteins at present separation distances. We applied these methods to the plastocyanin/cytochrome c interaction, which is faster than random collision, but too slow for study by molecular dynamics techniques. Significant electrostatic potentials were concentrated on one-fourth (969 A2) of the plastocyanin surface, with the greatest negative potential centered on the Tyr-83 hydroxyl within the acidic patch, and on one-eighth (632 A2) of the cytochrome c surface, with the greatest positive potential centered near the exposed heme edge. Coherent electrostatic fields occurred only over these regions, suggesting that local, rather than global, charge complementarity controls productive recognition. The three energetically favored families of pre-collision orientations all directed the positive region surrounding the heme edge of cytochrome c toward the acidic patch of plastocyanin but differed in heme plane orientation. Analysis of electrostatic fields, electrostatic energies of precollision orientations with 12 and 6 A separation distances, and surface topographies suggested that the favored orientations should converge to productive complexes promoting a single electron-transfer pathway from the cytochrome c heme edge to Tyr-83 of plastocyanin. Direct interactions of the exposed Cu ligand in plastocyanin with the cytochrome c heme edge are not unfavorable sterically or electrostatically but should occur no faster than randomly, indicating that this is not the primary pathway for electron transfer.

Excellent field emission properties of vertically oriented CuO nanowire films

NASA Astrophysics Data System (ADS)

Feng, Long; Yan, Hui; Li, Heng; Zhang, Rukang; Li, Zhe; Chi, Rui; Yang, Shuaiyu; Ma, Yaya; Fu, Bin; Liu, Jiwen

2018-04-01

Oriented CuO nanowire films were synthesized on a large scale using simple method of direct heating copper grids in air. The field emission properties of the sample can be enhanced by improving the aspect ratio of the nanowires just through a facile method of controlling the synthesis conditions. Although the density of the nanowires is large enough, the screen effect is not an important factor in this field emission process because few nanowires sticking out above the rest. Benefiting from the unique geometrical and structural features, the CuO nanowire samples show excellent field emission (FE) properties. The FE measurements of CuO nanowire films illustrate that the sample synthesized at 500 °C for 8 h has a comparatively low turn-on field of 0.68 V/μm, a low threshold field of 1.1 V/μm, and a large field enhancement factor β of 16782 (a record high value for CuO nanostructures, to the best of our knowledge), indicating that the samples are promising candidates for field emission applications.

Windsock memory COnditioned RAM (CO-RAM) pressure effect: Forced reconnection in the Earth's magnetotail

NASA Astrophysics Data System (ADS)

Vörös, Z.; Facskó, G.; Khodachenko, M.; Honkonen, I.; Janhunen, P.; Palmroth, M.

2014-08-01

Magnetic reconnection (MR) is a key physical concept explaining the addition of magnetic flux to the magnetotail and closed flux lines back-motion to the dayside magnetosphere. This scenario elaborated by Dungey (1963) can explain many aspects of solar wind-magnetosphere interaction processes, including substorms. However, neither the Dungey model nor its numerous modifications were able to explain fully the onset conditions for MR in the tail. In this paper, we introduce new onset conditions for forced MR in the tail. We call our scenario the "windsock memory conditioned ram pressure effect." Our nonflux transfer-associated forcing is introduced by a combination of the large-scale windsock motions exhibiting memory effects and solar wind dynamic pressure actions on the nightside magnetopause during northward oriented interplanetary magnetic field (IMF). Using global MHD Grand Unified Magnetosphere Ionosphere Coupling Simulation version 4 simulation results, upstream data from Wind, magnetosheath data from Cluster 1 and distant tail data from the two-probe Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun mission, we show that the simultaneous occurrence of vertical windsock motions of the magnetotail and enhanced solar wind dynamic pressure introduces strong nightside disturbances, including enhanced electric fields and persistent vertical cross-tail shear flows. These perturbations, associated with a stream interaction region in the solar wind, drive MR in the tail during episodes of northward oriented interplanetary magnetic field (IMF). We detect MR indirectly, observing plasmoids in the tail and ground-based signatures of earthward moving fast flows. We also consider the application to solar system planets and close-in exoplanets, where the proposed scenario can elucidate some new aspects of solar/stellar wind-magnetosphere interactions.

Orientation Guidance and Control for Marine Vehicles in the Horizontal Plane

DTIC Science & Technology

1991-06-01

FIELD GROUP SUB-GROUP Autonomous vehicles , Guidance and control, Stability, Path keeping 19 ABSIRACT (Continue on reverse if necessary and identify by...following in 3-D space. 33 LIST OF REFERENCES 1. Kanayama, Y. and Hartman, B.I. (1989) " Smooth local path planning for autonomous vehicles , " Proceeding

Discrete wavelet transform and energy eigen value for rotor bars fault detection in variable speed field-oriented control of induction motor drive.

PubMed

Ameid, Tarek; Menacer, Arezki; Talhaoui, Hicham; Azzoug, Youness

2018-05-03

This paper presents a methodology for the broken rotor bars fault detection is considered when the rotor speed varies continuously and the induction machine is controlled by Field-Oriented Control (FOC). The rotor fault detection is obtained by analyzing a several mechanical and electrical quantities (i.e., rotor speed, stator phase current and output signal of the speed regulator) by the Discrete Wavelet Transform (DWT) in variable speed drives. The severity of the fault is obtained by stored energy calculation for active power signal. Hence, it can be a useful solution as fault indicator. The FOC is implemented in order to preserve a good performance speed control; to compensate the broken rotor bars effect in the mechanical speed and to ensure the operation continuity and to investigate the fault effect in the variable speed. The effectiveness of the technique is evaluated in simulation and in a real-time implementation by using Matlab/Simulink with the real-time interface (RTI) based on dSpace 1104 board. Copyright © 2018. Published by Elsevier Ltd.

Fault ride-through enhancement using an enhanced field oriented control technique for converters of grid connected DFIG and STATCOM for different types of faults.

PubMed

Ananth, D V N; Nagesh Kumar, G V

2016-05-01

With increase in electric power demand, transmission lines were forced to operate close to its full load and due to the drastic change in weather conditions, thermal limit is increasing and the system is operating with less security margin. To meet the increased power demand, a doubly fed induction generator (DFIG) based wind generation system is a better alternative. For improving power flow capability and increasing security STATCOM can be adopted. As per modern grid rules, DFIG needs to operate without losing synchronism called low voltage ride through (LVRT) during severe grid faults. Hence, an enhanced field oriented control technique (EFOC) was adopted in Rotor Side Converter of DFIG converter to improve power flow transfer and to improve dynamic and transient stability. A STATCOM is coordinated to the system for obtaining much better stability and enhanced operation during grid fault. For the EFOC technique, rotor flux reference changes its value from synchronous speed to zero during fault for injecting current at the rotor slip frequency. In this process DC-Offset component of flux is controlled, decomposition during symmetric and asymmetric faults. The offset decomposition of flux will be oscillatory in a conventional field oriented control, whereas in EFOC it was aimed to damp quickly. This paper mitigates voltage and limits surge currents to enhance the operation of DFIG during symmetrical and asymmetrical faults. The system performance with different types of faults like single line to ground, double line to ground and triple line to ground was applied and compared without and with a STATCOM occurring at the point of common coupling with fault resistance of a very small value at 0.001Ω. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

The magnetic orientation of the Antarctic amphipod Gondogeneia antarctica is cancelled by very weak radiofrequency fields.

PubMed

Tomanova, K; Vacha, M

2016-06-01

Studies on weak man-made radiofrequency (RF) electromagnetic fields affecting animal magnetoreception aim for a better understanding of the reception mechanism and also point to a new phenomenon having possible consequences in ecology and environmental protection. RF impacts on magnetic compasses have recently been demonstrated in migratory birds and other vertebrates. We set out to investigate the effect of RF on the magnetic orientation of the Antarctic krill species Gondogeneia antarctica, a small marine crustacean widespread along the Antarctic littoral line. Here, we show that upon release, G. antarctica (held under laboratory conditions) escaped in the magnetically seaward direction along the magnetic sea-land axis (y-axis) of the home beach. However, the animals were disoriented after being exposed to RF. Orientation was lost not only in an RF field with a magnetic flux density of 20 nT, as expected according to the literature, but even under the 2 nT originally intended as a control. Our results extend recent findings of the extraordinary sensitivity of animal magnetoreception to weak RF fields in marine invertebrates. © 2016. Published by The Company of Biologists Ltd.

Thermodynamics of the Electric Field Induced Orientation of Nematic Droplet/Polymer Films

NASA Astrophysics Data System (ADS)

Drzaic, Paul S.

1989-07-01

Films consisting of micron-sized nematic liquid crystal droplets dispersed in a polymer matrix (NCAP) represent an important new class of electro-optical devices. These films strongly scatter light in the tm powered state, but achieve a high degree of clarity when an electric field is applied. In this report we describe the aspects of liquid crystal and polymer composition that control the magnitude of the electric field required to orient the nematic droplets. The droplet shape is found to be an important factor in the electro-optical response of these films. In films deposited from aqueous solutions the nematic cavities in the film are usually oblate in nature, with the short axis perpendicular to the film plane. The nematic, which adopts a bipolar configuration within the cavity, is preferentially aligned so that each droplet's symmetry axis is aligned parallel to the film plane in the rest state, but rotates to lie parallel with the field in the powered state. Capacitance data is presented which supports this picture. It is shown that the nematic droplet shape can be a major factor in determining the thermodynamics of droplet orientation.

53. VIEW OF TIRRILL VOLTAGE REGULATOR LOCATED ON SOUTH WALL ...

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

53. VIEW OF TIRRILL VOLTAGE REGULATOR LOCATED ON SOUTH WALL OF CONTROL ROOM. THE SOLENOID COILS AT THE TOP RIGHT OF THE PHOTOGRAPH DETECT VARIATIONS IN VOLTAGE AND CURRENT. THE ARMATURES OF THESE COILS ACT ON A SPRING LOADED BEAM. MOVEMENT OF THIS BEAM INDIRECTLY CONTROL SWITCHES WHICH CAUSE RESISTANCE GRIDS TO BE SWITCHED IN OR OUT OF THE EXCITER GENERATOR FIELD COILS (SEE CT-142A-95). - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

OPTIMIZING GLOBAL CORONAL MAGNETIC FIELD MODELS USING IMAGE-BASED CONSTRAINTS

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

Jones, Shaela I.; Davila, Joseph M.; Uritsky, Vadim, E-mail: shaela.i.jonesmecholsky@nasa.gov

The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in the heliosphere. It provides energy for coronal heating, controls the release of coronal mass ejections, and drives heliospheric and magnetospheric activity, yet the coronal magnetic field itself has proven difficult to measure. This difficulty has prompted a decades-long effort to develop accurate, timely, models of the field—an effort that continues today. We have developed a method for improving global coronal magnetic field models by incorporating the type of morphological constraints that could be derived from coronal images. Here we report promising initial tests of thismore » approach on two theoretical problems, and discuss opportunities for application.« less

Seed orientation and magnetic field strength have more influence on tomato seed performance than relative humidity and duration of exposure to non-uniform static magnetic fields.

PubMed

Poinapen, Danny; Brown, Daniel C W; Beeharry, Girish K

2013-09-15

Different factors (e.g., light, humidity, and temperature) including exposure to static magnetic fields (SMFs), referred here as critical factors, can significantly affect horticultural seed performance. However, the link between magnetic field parameters and other interdependent factors affecting seed viability is unclear. The importance of these critical factors affecting tomato (Solanum lycopersicum L.) var. MST/32 seed performance was assessed after performing several treatments based on a L9 (3(4)) (four factors at three levels) orthogonal array (OA) design. The variable factors in the design were magnetic flux density (R1=332.1±37.8mT; R2=108.7±26.9mT; and R3=50.6±10.5mT), exposure time (1, 2, and 24h), seed orientation (North polarity, South polarity, and control - no magnetic field), and relative humidity (RH) (7.0, 25.5, and 75.5%). After seed moisture content stabilisation at the different chosen RH, seeds were exposed in dark under laboratory conditions to several treatments based on the OA design before performance evaluation. Treatments not employing magnetic field exposure were used as controls. Results indicate that electrolyte leakage rate was reduced by a factor of 1.62 times during seed imbibition when non-uniform SMFs were employed. Higher germination (∼11.0%) was observed in magnetically-exposed seeds than in non-exposed ones, although seedlings emerging from SMF treatments did not show a consistent increase in biomass accumulation. The respective influence of the four critical factors tested on seed performance was ranked (in decreasing order) as seed orientation to external magnetic fields, magnetic field strength, RH, and exposure time. This study suggests a significant effect of non-uniform SMFs on seed performance with respect to RH, and more pronounced effects are observed during seed imbibition rather than during later developmental stages. Copyright © 2013 Elsevier GmbH. All rights reserved.

Effect of Strain Restored Energy on Abnormal Grain Growth in Mg Alloy Simulated by Phase Field Methods

NASA Astrophysics Data System (ADS)

Wu, Yan; Huang, Yuan-yuan

2018-03-01

Abnormal grain growth of single phase AZ31 Mg alloy in the spatio-temporal process has been simulated by phase field models, and the influencing factors of abnormal grain growth are studied in order to find the ways to control secondary recrystallization in the microstructure. The study aims to find out the mechanisms for abnormal grain growth in real alloys. It is shown from the simulated results that the abnormal grain growth can be controlled by the strain restored energy. Secondary recrystallization after an annealing treatment can be induced if there are grains of a certain orientation in the microstructure with local high restored energy. However, if the value of the local restored energy at a certain grain orientation is not greater than 1.1E 0, there may be no abnormal grain growth in the microstructure.

Learning About Love: A Meta-Analytic Study of Individually-Oriented Relationship Education Programs for Adolescents and Emerging Adults.

PubMed

Simpson, David M; Leonhardt, Nathan D; Hawkins, Alan J

2018-03-01

Despite recent policy initiatives and substantial federal funding of individually oriented relationship education programs for youth, there have been no meta-analytic reviews of this growing field. This meta-analytic study draws on 17 control-group studies and 13 one-group/pre-post studies to evaluate the effectiveness of relationship education programs on adolescents' and emerging adults' relationship knowledge, attitudes, and skills. Overall, control-group studies produced a medium effect (d = .36); one-group/pre-post studies also produced a medium effect (d = .47). However, the lack of studies with long-term follow-ups of relationship behaviors in the young adult years is a serious weakness in the field, limiting what we can say about the value of these programs for helping youth achieve their aspirations for healthy romantic relationships and stable marriages.

The establishment and application of direct coupled electrostatic-structural field model in electrostatically controlled deployable membrane antenna

NASA Astrophysics Data System (ADS)

Gu, Yongzhen; Duan, Baoyan; Du, Jingli

2018-05-01

The electrostatically controlled deployable membrane antenna (ECDMA) is a promising space structure due to its low weight, large aperture and high precision characteristics. However, it is an extreme challenge to describe the coupled field between electrostatic and membrane structure accurately. A direct coupled method is applied to solve the coupled problem in this paper. Firstly, the membrane structure and electrostatic field are uniformly described by energy, considering the coupled problem is an energy conservation phenomenon. Then the direct coupled electrostatic-structural field governing equilibrium equations are obtained by energy variation approach. Numerical results show that the direct coupled method improves the computing efficiency by 36% compared with the traditional indirect coupled method with the same level accuracy. Finally, the prototype has been manufactured and tested and the ECDMA finite element simulations show good agreement with the experiment results as the maximum surface error difference is 6%.

Virtual and flexible digital signal processing system based on software PnP and component works

NASA Astrophysics Data System (ADS)

He, Tao; Wu, Qinghua; Zhong, Fei; Li, Wei

2005-05-01

An idea about software PnP (Plug & Play) is put forward according to the hardware PnP. And base on this idea, a virtual flexible digital signal processing system (FVDSPS) is carried out. FVDSPS is composed of a main control center, many sub-function modules and other hardware I/O modules. Main control center sends out commands to sub-function modules, and manages running orders, parameters and results of sub-functions. The software kernel of FVDSPS is DSP (Digital Signal Processing) module, which communicates with the main control center through some protocols, accept commands or send requirements. The data sharing and exchanging between the main control center and the DSP modules are carried out and managed by the files system of the Windows Operation System through the effective communication. FVDSPS real orients objects, orients engineers and orients engineering problems. With FVDSPS, users can freely plug and play, and fast reconfigure a signal process system according to engineering problems without programming. What you see is what you get. Thus, an engineer can orient engineering problems directly, pay more attention to engineering problems, and promote the flexibility, reliability and veracity of testing system. Because FVDSPS orients TCP/IP protocol, through Internet, testing engineers, technology experts can be connected freely without space. Engineering problems can be resolved fast and effectively. FVDSPS can be used in many fields such as instruments and meter, fault diagnosis, device maintenance and quality control.

Helping employees sleep well: Effects of cognitive behavioral therapy for insomnia on work outcomes.

PubMed

Barnes, Christopher M; Miller, Jared A; Bostock, Sophie

2017-01-01

Drawing from recent research advances indicating the harmful effects of insomnia on negative affect, job satisfaction, self-control, organizational citizenship behavior, and interpersonal deviance, we hypothesized that treating insomnia with Internet based cognitive behavior therapy for insomnia would lead to improvements in these outcomes. In a field experiment with a randomized wait-list control group, we found that treatment had a beneficial direct effect on negative affect, job satisfaction, and self-control. Moreover, the effect of treatment on job satisfaction was mediated by negative affect. We were not able to detect a direct effect of treatment on organizational citizenship behavior or interpersonal deviance. However, treatment had a beneficial indirect effect on organizational citizenship behavior through the mediators of negative affect and job satisfaction, and a beneficial indirect effect on interpersonal deviance through the mediator of self-control. These results move the applied psychology literature on insomnia beyond simply pointing out problematic effects of employee insomnia to providing evidence of a partial solution to such effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Structural basis of orientation sensitivity of cat retinal ganglion cells.

PubMed

Leventhal, A G; Schall, J D

1983-11-10

We investigated the structural basis of the physiological orientation sensitivity of retinal ganglion cells (Levick and Thibos, '82). The dendritic fields of 840 retinal ganglion cells labeled by injections of horseradish peroxidase into the dorsal lateral geniculate nucleus (LGNd) or optic tracts of normal cats. Siamese cats, and cat deprived of patterned visual experience from birth by monocular lid-suture (MD) were studied. Mathematical techniques designed to analyze direction were used to find the dendritic field orientation of each cell. Statistical techniques designed for angular data were used to determine the relationship between dendritic field orientation and angular position on the retina (polar angle). Our results indicate that 88% of retinal ganglion cells have oriented dendritic fields and that dendritic field orientation is related systematically to retinal position. In all regions of retina more that 0.5 mm from the area centralis the dendritic fields of retinal ganglion cells are oriented radially, i.e., like the spokes of a wheel having the area centralis at its hub. This relationship was present in all animals and cell types studied and was strongest for cells located close to the horizontal meridian (visual streak) of the retina. Retinal ganglion cells appear to be sensitive to stimulus orientation because they have oriented dendritic fields.

Direct vs. indirect pathway for nitrobenzene reduction reaction on a Ni catalyst surface: a density functional study.

PubMed

Mahata, Arup; Rai, Rohit K; Choudhuri, Indrani; Singh, Sanjay K; Pathak, Biswarup

2014-12-21

Density functional theory (DFT) calculations are performed to understand and address the previous experimental results that showed the reduction of nitrobenzene to aniline prefers direct over indirect reaction pathways irrespective of the catalyst surface. Nitrobenzene to aniline conversion occurs via the hydroxyl amine intermediate (direct pathway) or via the azoxybenzene intermediate (indirect pathway). Through our computational study we calculated the spin polarized and dispersion corrected reaction energies and activation barriers corresponding to various reaction pathways for the reduction of nitrobenzene to aniline over a Ni catalyst surface. The adsorption behaviour of the substrate, nitrobenzene, on the catalyst surface was also considered and the energetically most preferable structural orientation was elucidated. Our study indicates that the parallel adsorption behaviour of the molecules over a catalyst surface is preferable over vertical adsorption behaviour. Based on the reaction energies and activation barrier of the various elementary steps involved in direct or indirect reaction pathways, we find that the direct reduction pathway of nitrobenzene over the Ni(111) catalyst surface is more favourable than the indirect reaction pathway.

A second-order orientation-contrast stimulus for population-receptive-field-based retinotopic mapping.

PubMed

Yildirim, Funda; Carvalho, Joana; Cornelissen, Frans W

2018-01-01

Visual field or retinotopic mapping is one of the most frequently used paradigms in fMRI. It uses activity evoked by position-varying high luminance contrast visual patterns presented throughout the visual field for determining the spatial organization of cortical visual areas. While the advantage of using high luminance contrast is that it tends to drive a wide range of neural populations - thus resulting in high signal-to-noise BOLD responses - this may also be a limitation, especially for approaches that attempt to squeeze more information out of the BOLD response, such as population receptive field (pRF) mapping. In that case, more selective stimulation of a subset of neurons - despite reduced signals - could result in better characterization of pRF properties. Here, we used a second-order stimulus based on local differences in orientation texture - to which we refer as orientation contrast - to perform retinotopic mapping. Participants in our experiment viewed arrays of Gabor patches composed of a foreground (a bar) and a background. These could only be distinguished on the basis of a difference in patch orientation. In our analyses, we compare the pRF properties obtained using this new orientation contrast-based retinotopy (OCR) to those obtained using classic luminance contrast-based retinotopy (LCR). Specifically, in higher order cortical visual areas such as LO, our novel approach resulted in non-trivial reductions in estimated population receptive field size of around 30%. A set of control experiments confirms that the most plausible cause for this reduction is that OCR mainly drives neurons sensitive to orientation contrast. We discuss how OCR - by limiting receptive field scatter and reducing BOLD displacement - may result in more accurate pRF localization as well. Estimation of neuronal properties is crucial for interpreting cortical function. Therefore, we conclude that using our approach, it is possible to selectively target particular neuronal populations, opening the way to use pRF modeling to dissect the response properties of more clearly-defined neuronal populations in different visual areas. Copyright © 2017 Elsevier Inc. All rights reserved.

Essentialist beliefs, sexual identity uncertainty, internalized homonegativity and psychological wellbeing in gay men.

PubMed

Morandini, James S; Blaszczynski, Alexander; Ross, Michael W; Costa, Daniel S J; Dar-Nimrod, Ilan

2015-07-01

The present study examined essentialist beliefs about sexual orientation and their implications for sexual identity uncertainty, internalized homonegativity and psychological wellbeing in a sample of gay men. A combination of targeted sampling and snowball strategies were used to recruit 639 gay identifying men for a cross-sectional online survey. Participants completed a questionnaire assessing sexual orientation beliefs, sexual identity uncertainty, internalized homonegativity, and psychological wellbeing outcomes. Structural equation modeling was used to test whether essentialist beliefs were associated with psychological wellbeing indirectly via their effect on sexual identity uncertainty and internalized homonegativity. A unique pattern of direct and indirect effects was observed in which facets of essentialism predicted sexual identity uncertainty, internalized homonegativity and psychological wellbeing. Of note, viewing sexual orientation as immutable/biologically based and as existing in discrete categories, were associated with less sexual identity uncertainty. On the other hand, these beliefs had divergent relationships with internalized homonegativity, with immutability/biological beliefs associated with lower, and discreteness beliefs associated with greater internalized homonegativity. Of interest, although sexual identity uncertainty was associated with poorer psychological wellbeing via its contribution to internalized homophobia, there was no direct relationship between identity uncertainty and psychological wellbeing. Findings indicate that essentializing sexual orientation has mixed implications for sexual identity uncertainty and internalized homonegativity and wellbeing in gay men. Those undertaking educational and clinical interventions with gay men should be aware of the benefits and of caveats of essentialist theories of homosexuality for this population. (c) 2015 APA, all rights reserved).

The coil orientation dependency of the electric field induced by TMS for M1 and other brain areas.

PubMed

Janssen, Arno M; Oostendorp, Thom F; Stegeman, Dick F

2015-05-17

The effectiveness of transcranial magnetic stimulation (TMS) depends highly on the coil orientation relative to the subject's head. This implies that the direction of the induced electric field has a large effect on the efficiency of TMS. To improve future protocols, knowledge about the relationship between the coil orientation and the direction of the induced electric field on the one hand, and the head and brain anatomy on the other hand, seems crucial. Therefore, the induced electric field in the cortex as a function of the coil orientation has been examined in this study. The effect of changing the coil orientation on the induced electric field was evaluated for fourteen cortical targets. We used a finite element model to calculate the induced electric fields for thirty-six coil orientations (10 degrees resolution) per target location. The effects on the electric field due to coil rotation, in combination with target site anatomy, have been quantified. The results confirm that the electric field perpendicular to the anterior sulcal wall of the central sulcus is highly susceptible to coil orientation changes and has to be maximized for an optimal stimulation effect of the motor cortex. In order to obtain maximum stimulation effect in areas other than the motor cortex, the electric field perpendicular to the cortical surface in those areas has to be maximized as well. Small orientation changes (10 degrees) do not alter the induced electric field drastically. The results suggest that for all cortical targets, maximizing the strength of the electric field perpendicular to the targeted cortical surface area (and inward directed) optimizes the effect of TMS. Orienting the TMS coil based on anatomical information (anatomical magnetic resonance imaging data) about the targeted brain area can improve future results. The standard coil orientations, used in cognitive and clinical neuroscience, induce (near) optimal electric fields in the subject-specific head model in most cases.

Auditory perception and the control of spatially coordinated action of deaf and hearing children.

PubMed

Savelsbergh, G J; Netelenbos, J B; Whiting, H T

1991-03-01

From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained.

Optical spin orientation of minority holes in a modulation-doped GaAs/(Ga,Al)As quantum well

NASA Astrophysics Data System (ADS)

Koudinov, A. V.; Dzhioev, R. I.; Korenev, V. L.; Sapega, V. F.; Kusrayev, Yu. G.

2016-04-01

The optical spin orientation effect in a GaAs/(Ga,Al)As quantum well containing a high-mobility two-dimensional electron gas was found to be due to spin-polarized minority carriers, the holes. The observed oscillations of both the intensity and polarization of the photoluminescence in a magnetic field are well described in a model whose main elements are resonant absorption of the exciting light by the Landau levels and mixing of the heavy- and light-hole subbands. After subtraction of these effects, the observed influence of magnetic fields on the spin polarization can be well interpreted by a standard approach of the optical orientation method. The spin relaxation of holes is controlled by the Dyakonov-Perel' mechanism. Deceleration of the spin relaxation by the magnetic field occurs through the Ivchenko mechanism—due to the cyclotron motion of holes. Mobility of holes was found to be two orders of magnitude smaller than that of electrons, being determined by the scattering of holes by the electron gas.

Indirect measurement of N-14 quadrupolar coupling for NH3 intercalated in potassium graphite

NASA Technical Reports Server (NTRS)

Tsang, T.; Fronko, R. M.; Resing, H. A.

1987-01-01

A method for indirect measurement of the nuclear quadrupolar coupling was developed and applied to NH3 molecules in the graphite intercalation compound K(NH3)4.3C24, which has a layered structure with alternating carbon and intercalant layers. Three triplets were observed in the H-1 NMR spectra of the compound. The value of the N-14 quadrupolar coupling constant of NH3 (3.7 MHz), determined indirectly from the H-1 NMR spectra, was intermediate between the gas value of 4.1 MHz and the solid-state value of 3.2 MHz. The method was also used to deduce the (H-1)-(H-1) and (N-14)-(H-1) dipolar interactions, the H-1 chemical shifts, and the molecular orientations and motions of NH3.

Tuning polymorphism and orientation in organic semiconductor thin films via post-deposition processing.

PubMed

Hiszpanski, Anna M; Baur, Robin M; Kim, Bumjung; Tremblay, Noah J; Nuckolls, Colin; Woll, Arthur R; Loo, Yueh-Lin

2014-11-05

Though both the crystal structure and molecular orientation of organic semiconductors are known to impact charge transport in thin-film devices, separately accessing different polymorphs and varying the out-of-plane molecular orientation is challenging, typically requiring stringent control over film deposition conditions, film thickness, and substrate chemistry. Here we demonstrate independent tuning of the crystalline polymorph and molecular orientation in thin films of contorted hexabenzocoronene, c-HBC, during post-deposition processing without the need to adjust deposition conditions. Three polymorphs are observed, two of which have not been previously reported. Using our ability to independently tune the crystal structure and out-of-plane molecular orientation in thin films of c-HBC, we have decoupled and evaluated the effects that molecular packing and orientation have on device performance in thin-film transistors (TFTs). In the case of TFTs comprising c-HBC, polymorphism and molecular orientation are equally important; independently changing either one affects the field-effect mobility by an order of magnitude.

Influence of the interplanetary magnetic field on the occurrence and thickness of the plasma mantle

NASA Technical Reports Server (NTRS)

Sckopke, N.; Paschmann, G.; Rosenbauer, H.; Fairfield, D. H.

1976-01-01

The response of the plasma mantle to the orientation of the interplanetary magnetic field (IMF) has been studied by correlating Heos 2 plasma and Imp 6 magnetic field data. The mantle is nearly always present when the IMF has a southward component and often also when the field has a weak northward component. In addition, the mantle appears increasingly thicker with greater southward components. On the other hand, the mantle is thin or missing (from the region where it is normally found) when the average IMF has a strong northward component. This result supports the idea that polar cap convection plays a dominant role in the formation of the plasma mantle: mantle plasma originates in the magnetosheath, enters the magnetosphere through the day side polar cusps, and is transported across the cusp to the night side by means of a convection electric field whose magnitude is controlled by the orientation of the IMF.

Direct measurement of critical resolved shear stress of prismatic and basal slip in polycrystalline Ti using high energy X-ray diffraction microscopy

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

Wang, L.; Zheng, Z.; Phukan, H.

Knowledge of the critical resolved shear stress (CRSS) values of different slip modes is important for accurately modeling plastic deformation of hexagonal materials. Here, we demonstrate that CRSS can be directly measured with an in-situ high energy X-ray diffraction microscopy (HEDM) experiment. A commercially pure Ti tensile specimen was deformed up to 2.6% strain. In-situ far-field HEDM experiments were carried out to track the evolution of crystallographic orientations, centers of masses, and stress states of 1153 grains in a material volume of 1.1mm×1mm×1mm. Predominant prismatic slip was identified in 18 grains, where the orientation change occurred primarily by rotation aroundmore » the c-axis during specimen deformation. By analyzing the resolved shear stress on individual slip systems, the estimated CRSS for prismatic slip is 96±18 MPa. Predominant basal slip was identified in 22 other grains, where the 2 orientation change occurred primarily by tilting the c-axis about an axis in the basal plane. The estimated CRSS for basal slip is 127±33 MPa. The ratio of CRSS basal/CRSS prismatic is in the range of 1.7-2.1. From indirect assessment, the CRSS for pyramidal < c+a > slip is likely greater than 240MPa. Lastly, grain size and free surface effects on the CRSS value in different grains are also examined.« less

Evaluation of substance P as a neurotransmitter in equine jejunum.

PubMed

Malone, E D; Kannan, M S; Brown, D R

2000-10-01

To determine whether substance P (SP) functions as a neurotransmitter in equine jejunum. Samples of jejunum obtained from horses that did not have lesions in the gastrointestinal tract. Jejunal smooth muscle strips, oriented in the plane of the circular or longitudinal muscle, were suspended isometrically in muscle baths. Neurotransmitter release was induced by electrical field stimulation (EFS) delivered at 2 intensities (30 and 70 V) and various frequencies on muscle strips that were maintained at low tension or were under contraction. A neurokinin-1 receptor blocker (CP-96,345) was added to baths prior to EFS to interrupt SP neurotransmission. Additionally, direct effects of SP on muscle strips were evaluated, and SP-like immunoreactivity was localized in intestinal tissues, using indirect immunofluorescence testing. Substance P contracted circularly and longitudinally oriented muscle strips. Prior treatment with CP-96,345 altered muscle responses to SP and EFS, suggesting that SP was released from depolarized myenteric neurons. Depending on orientation of muscle strips and stimulation variables used, CP-96,345 increased or decreased the contractile response to EFS. Substance P-like immunoreactivity was detected in the myenteric plexus and circular muscle layers. Substance P appears to function as a neurotransmitter in equine jejunum. It apparently modulates smooth muscle contractility, depending on preexisting conditions. Effects of SP may be altered in some forms of intestinal dysfunction. Altering SP neurotransmission in the jejunum may provide a therapeutic option for motility disorders of horses that are unresponsive to adrenergic and cholinergic drugs.

Direct measurement of critical resolved shear stress of prismatic and basal slip in polycrystalline Ti using high energy X-ray diffraction microscopy

DOE PAGES

Wang, L.; Zheng, Z.; Phukan, H.; ...

2017-05-07

Knowledge of the critical resolved shear stress (CRSS) values of different slip modes is important for accurately modeling plastic deformation of hexagonal materials. Here, we demonstrate that CRSS can be directly measured with an in-situ high energy X-ray diffraction microscopy (HEDM) experiment. A commercially pure Ti tensile specimen was deformed up to 2.6% strain. In-situ far-field HEDM experiments were carried out to track the evolution of crystallographic orientations, centers of masses, and stress states of 1153 grains in a material volume of 1.1mm×1mm×1mm. Predominant prismatic slip was identified in 18 grains, where the orientation change occurred primarily by rotation aroundmore » the c-axis during specimen deformation. By analyzing the resolved shear stress on individual slip systems, the estimated CRSS for prismatic slip is 96±18 MPa. Predominant basal slip was identified in 22 other grains, where the 2 orientation change occurred primarily by tilting the c-axis about an axis in the basal plane. The estimated CRSS for basal slip is 127±33 MPa. The ratio of CRSS basal/CRSS prismatic is in the range of 1.7-2.1. From indirect assessment, the CRSS for pyramidal < c+a > slip is likely greater than 240MPa. Lastly, grain size and free surface effects on the CRSS value in different grains are also examined.« less

Electric field control of magnetic states in isolated and dipole-coupled FeGa nanomagnets delineated on a PMN-PT substrate.

PubMed

Ahmad, Hasnain; Atulasimha, Jayasimha; Bandyopadhyay, Supriyo

2015-10-09

We report observation of a 'non-volatile' converse magneto-electric effect in elliptical FeGa nanomagnets delineated on a piezoelectric PMN-PT substrate. The nanomagnets are first magnetized with a magnetic field directed along their nominal major axes. Subsequent application of a strong electric field across the piezoelectric substrate generates strain in the substrate, which is partially transferred to the nanomagnets and rotates the magnetizations of some of them away from their initial orientations. The rotated magnetizations remain in their new orientations after the field is removed, resulting in 'non-volatility'. In isolated nanomagnets, the magnetization rotates by <90° upon application of the electric field, but in a dipole-coupled pair consisting of one 'hard' and one 'soft' nanomagnet, which are both initially magnetized in the same direction by the magnetic field, the soft nanomagnet's magnetization rotates by [Formula: see text] upon application of the electric field because of the dipole influence of the hard nanomagnet. This effect can be utilized for a nanomagnetic NOT logic gate.

Shared Leadership Improves Team Novelty: The Mechanism and Its Boundary Condition

PubMed Central

Sun, Xiaomin; Jie, Yuan; Wang, Yilu; Xue, Gang; Liu, Yan

2016-01-01

Previous research has revealed the significant impact of shared leadership on team creativity, yet the mechanism underlying this relationship has rarely been investigated. The current research examined how shared leadership influenced team creativity (novelty and usefulness) across 3 studies using both long-term project teams and temporal task teams in the laboratory. The results showed that shared leadership enhanced the novelty dimension of team creativity by improving constructive controversy. Furthermore, team goal orientation moderated this effect. The indirect effect of constructive controversy holds for teams with learning goal orientation but not for those with performance goal orientation. Such patterns were not found in the usefulness dimension of team creativity. PMID:28066289

Popularity and Resource Control Goals as Predictors of Adolescent Indirect Aggression.

PubMed

Dyches, Karmon D; Mayeux, Lara

2015-01-01

Resource Control Theory conceptualizes aggression as a behavior that allows access to, and control of, limited resources (P. H. Hawley, 1999 ). This study investigated the associations of adolescents' indirect aggression with their resource control goals, or goals related to controlling social resources such as dating opportunities and peer status, and with their levels of popularity and social intelligence. Participants were 109 seventh-graders (52% girls) who completed a resource control goals measure, the Tromsø Social Intelligence Scale, and peer nominations of popularity and indirect aggression. Results indicated positive associations between resource control goals and peer-nominated indirect aggression, with popularity further moderating these associations. These findings suggest that the resource control goals of adolescents can be a motivating force to engage in hurtful behaviors. They provide a context from which peer relations researchers can improve their understanding and prevention of adolescents' indirect aggression.

System analysis through bond graph modeling

NASA Astrophysics Data System (ADS)

McBride, Robert Thomas

2005-07-01

Modeling and simulation form an integral role in the engineering design process. An accurate mathematical description of a system provides the design engineer the flexibility to perform trade studies quickly and accurately to expedite the design process. Most often, the mathematical model of the system contains components of different engineering disciplines. A modeling methodology that can handle these types of systems might be used in an indirect fashion to extract added information from the model. This research examines the ability of a modeling methodology to provide added insight into system analysis and design. The modeling methodology used is bond graph modeling. An investigation into the creation of a bond graph model using the Lagrangian of the system is provided. Upon creation of the bond graph, system analysis is performed. To aid in the system analysis, an object-oriented approach to bond graph modeling is introduced. A framework is provided to simulate the bond graph directly. Through object-oriented simulation of a bond graph, the information contained within the bond graph can be exploited to create a measurement of system efficiency. A definition of system efficiency is given. This measurement of efficiency is used in the design of different controllers of varying architectures. Optimal control of a missile autopilot is discussed within the framework of the calculated system efficiency.

Modulating protein behaviors on responsive surface by external electric fields: A molecular dynamics study

NASA Astrophysics Data System (ADS)

Xie, Yun; Pan, Yufang; Zhang, Rong; Liang, Ying; Li, Zhanchao

2015-01-01

Molecular dynamics simulations were employed to investigate the modulation of protein behaviors on the electrically responsive zwitterionic phosphorylcholine self-assembled monolayers (PC-SAMs). Results show that PC-SAMs could sensitively respond to the applied electric fields and exhibit three states with different charge distributions, namely both the negatively charged phosphate groups and the positively charged choline groups are exposed to the solution in the absence of electric fields (state 1), phosphate groups exposed in the presence of positive electric fields (state 2), and choline groups exposed in the presence of negative electric fields (state 3). Under state 1, the adsorption of Cyt c on the PC-SAM is reversible and the orientations of Cyt c are randomly distributed. Under state 2, the adsorption of Cyt c is enhanced due to the electrostatic attractions between the exposed phosphate groups and the positively charged protein; when adsorbed on the PC-SAMs, Cyt c tends to adopt the orientation with the heme plane perpendicular to the surface plane, and the percentage of this orientation increases as the field strength rises up. Under state 3, the adsorption of Cyt c is retarded because of the electrostatic repulsions between the exposed choline groups and the protein; however, if the gaps between PC chains are large enough, Cyt c could insert into the PC-SAM and access the phosphate groups after overcoming a slight energy barrier. Under three states, the basic backbone structures of Cyt c are well kept within the simulation time since the conformation of Cyt c is mainly affected by the surface-generated electric fields, whose strengths are modulated by the external electric fields and are not strong enough to deform protein. The results indicate the possibility of regulating protein behaviors, including promoting or retarding protein adsorption and regulating protein orientations, on responsive surfaces by applying electric fields on the surfaces without worrying protein deformation, which may be helpful in the applications of protein separation and controlled drug delivery.

Electric-Field-Oriented Growth of Long Hair-Like Silica Microfibrils and Derived Functional Monolithic Solids

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

Hu, Michael Z.; DePaoli, David W.; Kuritz, Tanya

We present a “bottom-up” fabrication approach to first grow a new class of inorganic (silica) long hair-like microfibers or microwires and then to form monolithic solid pellet that contains parallel arrays of bundled microfibers with a controlled orientation. During the sol-gel solution processing, reactive precursor species are utilized as molecular “building blocks” for the field-directed assembly growth of microfibers driven by an electric field of pulsed direct current (dc) with controlled frequency. In principle, this reactive electrofibrilation process that combines an external field with a solid-phase nucleation and growth process has no limitation on reactions (such as the one heremore » that involves sol-gel reaction chemistry) and on materials compositions (such as the example silica oxide), thus will enable bulk production of long microfibers of wide variety of inorganic materials (other oxides or metals). Furthermore, we have fabricated uniquely architectured monolithic solid materials containing aligned microfibers by “wet press” of the in-situ grown microfiber structure in the electric field. The consolidated monolithic slabs (1 cm x 1 cm x 3 mm) have shown anisotropic properties and desirable retention of DNA molecule fragments, thus, could serve as a platform stationary-phase materials for future development of capillary electrochromatography for biomolecule separations.« less

Electric-Field-Oriented Growth of Long Hair-Like Silica Microfibrils and Derived Functional Monolithic Solids

DOE PAGES

Hu, Michael Z.; DePaoli, David W.; Kuritz, Tanya; ...

2017-09-11

We present a “bottom-up” fabrication approach to first grow a new class of inorganic (silica) long hair-like microfibers or microwires and then to form monolithic solid pellet that contains parallel arrays of bundled microfibers with a controlled orientation. During the sol-gel solution processing, reactive precursor species are utilized as molecular “building blocks” for the field-directed assembly growth of microfibers driven by an electric field of pulsed direct current (dc) with controlled frequency. In principle, this reactive electrofibrilation process that combines an external field with a solid-phase nucleation and growth process has no limitation on reactions (such as the one heremore » that involves sol-gel reaction chemistry) and on materials compositions (such as the example silica oxide), thus will enable bulk production of long microfibers of wide variety of inorganic materials (other oxides or metals). Furthermore, we have fabricated uniquely architectured monolithic solid materials containing aligned microfibers by “wet press” of the in-situ grown microfiber structure in the electric field. The consolidated monolithic slabs (1 cm x 1 cm x 3 mm) have shown anisotropic properties and desirable retention of DNA molecule fragments, thus, could serve as a platform stationary-phase materials for future development of capillary electrochromatography for biomolecule separations.« less

Effect of ac electric field on the dynamics of a vesicle under shear flow in the small deformation regime

NASA Astrophysics Data System (ADS)

Sinha, Kumari Priti; Thaokar, Rochish M.

2018-03-01

Vesicles or biological cells under simultaneous shear and electric field can be encountered in dielectrophoretic devices or designs used for continuous flow electrofusion or electroporation. In this work, the dynamics of a vesicle subjected to simultaneous shear and uniform alternating current (ac) electric field is investigated in the small deformation limit. The coupled equations for vesicle orientation and shape evolution are derived theoretically, and the resulting nonlinear equations are handled numerically to generate relevant phase diagrams that demonstrate the effect of electrical parameters on the different dynamical regimes such as tank treading (TT), vacillating breathing (VB) [called trembling (TR) in this work], and tumbling (TU). It is found that while the electric Mason number (Mn), which represents the relative strength of the electrical forces to the shear forces, promotes the TT regime, the response itself is found to be sensitive to the applied frequency as well as the conductivity ratio. While higher outer conductivity promotes orientation along the flow axis, orientation along the electric field is favored when the inner conductivity is higher. Similarly a switch of orientation from the direction of the electric field to the direction of flow is possible by a mere change of frequency when the outer conductivity is higher. Interestingly, in some cases, a coupling between electric field-induced deformation and shear can result in the system admitting an intermediate TU regime while attaining the TT regime at high Mn. The results could enable designing better dielectrophoretic devices wherein the residence time as well as the dynamical states of the vesicular suspension can be controlled as per the application.

Single molecular orientation switching of an endohedral metallofullerene.

PubMed

Yasutake, Yuhsuke; Shi, Zujin; Okazaki, Toshiya; Shinohara, Hisanori; Majima, Yutaka

2005-06-01

The single molecular orientation switching of the Tb@C82 endohedral metallofullerene has been studied by using low-temperature ultrahigh vacuum (UHV) scanning tunneling microscopy (STM). An octanethiol self-assembled monolayer (SAM) was introduced between Tb@C82 and the Au111 substrate to control the thermal rotational states of Tb@C82. Scanning tunneling spectroscopy (STS) of Tb@C82 on an octanethiol SAM at 13 K demonstrated hysteresis including negative differential conductance (NDC). This observed hysteresis and NDC is interpreted in terms of a switching of the Tb@C82 molecular orientation caused by the interaction between its electric dipole moment and an external electric field.

GCM Simulations of the Aerosol Indirect Effect: Sensitivity to Cloud Parameterization and Aerosol Burden

NASA Technical Reports Server (NTRS)

Menon, Surabi; DelGenio, Anthony D.; Koch, Dorothy; Tselioudis, George; Hansen, James E. (Technical Monitor)

2001-01-01

We describe the coupling of the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to an online sulfur chemistry model and source models for organic matter and sea-salt that is used to estimate the aerosol indirect effect. The cloud droplet number concentration is diagnosed empirically from field experiment datasets over land and ocean that observe droplet number and all three aerosol types simultaneously; corrections are made for implied variations in cloud turbulence levels. The resulting cloud droplet number is used to calculate variations in droplet effective radius, which in turn allows us to predict aerosol effects on cloud optical thickness and microphysical process rates. We calculate the aerosol indirect effect by differencing the top-of-the-atmosphere net cloud radiative forcing for simulations with present-day vs. pre-industrial emissions. Both the first (radiative) and second (microphysical) indirect effects are explored. We test the sensitivity of our results to cloud parameterization assumptions that control the vertical distribution of cloud occurrence, the autoconversion rate, and the aerosol scavenging rate, each of which feeds back significantly on the model aerosol burden. The global mean aerosol indirect effect for all three aerosol types ranges from -1.55 to -4.36 W m(exp -2) in our simulations. The results are quite sensitive to the pre-industrial background aerosol burden, with low pre-industrial burdens giving strong indirect effects, and to a lesser extent to the anthropogenic aerosol burden, with large burdens giving somewhat larger indirect effects. Because of this dependence on the background aerosol, model diagnostics such as albedo-particle size correlations and column cloud susceptibility, for which satellite validation products are available, are not good predictors of the resulting indirect effect.

GCM Simulations of the Aerosol Indirect Effect: Sensitivity to Cloud Parameterization and Aerosol Burden

NASA Technical Reports Server (NTRS)

Menon, Surabi; DelGenio, Anthony D.; Koch, Dorothy; Tselioudis, George; Hansen, James E. (Technical Monitor)

2001-01-01

We describe the coupling of the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to an online sulfur chemistry model and source models for organic matter and sea-salt that is used to estimate the aerosol indirect effect. The cloud droplet number concentration is diagnosed empirically from field experiment datasets over land and ocean that observe droplet number and all three aerosol types simultaneously; corrections are made for implied variations in cloud turbulence levels. The resulting cloud droplet number is used to calculate variations in droplet effective radius, which in turn allows us to predict aerosol effects on cloud optical thickness and microphysical process rates. We calculate the aerosol indirect effect by differencing the top-of-the-atmosphere net cloud radiative forcing for simulations with present-day vs. pre-industrial emissions. Both the first (radiative) and second (microphysical) indirect effects are explored. We test the sensitivity of our results to cloud parameterization assumptions that control the vertical distribution of cloud occurrence, the autoconversion rate, and the aerosol scavenging rate, each of which feeds back significantly on the model aerosol burden. The global mean aerosol indirect effect for all three aerosol types ranges from -1.55 to -4.36 W/sq m in our simulations. The results are quite sensitive to the pre-industrial background aerosol burden, with low pre-industrial burdens giving strong indirect effects, and to a lesser extent to the anthropogenic aerosol burden, with large burdens giving somewhat larger indirect effects. Because of this dependence on the background aerosol, model diagnostics such as albedo-particle size correlations and column cloud susceptibility, for which satellite validation products are available, are not good predictors of the resulting indirect effect.

Tuning Bacterial Hydrodynamics with Magnetic Fields: A Path to Bacterial Robotics

NASA Astrophysics Data System (ADS)

Pierce, Christopher; Mumper, Eric; Brangham, Jack; Wijesinghe, Hiran; Lower, Stephen; Lower, Brian; Yang, Fengyuan; Sooryakumar, Ratnasingham

Magnetotactic Bacteria (MTB) are a group of motile prokaryotes that synthesize chains of lipid-bound, magnetic nano-particles. In this study, the innate magnetism of these flagellated swimmers is exploited to explore their hydrodynamics near confining surfaces, using the magnetic field as a tuning parameter. With weak (Gauss), uniform, external, magnetic ?elds and the field gradients arising from micro-magnetic surface patterns, the relative strength of hydrodynamic, magnetic and ?agellar force components is tuned through magnetic control of the bacteria's orientation and position. In addition to direct measurement of several hydrodynamic quantities related to the motility of individual cells, their tunable dynamics reveal a number of novel, highly controllable swimming behaviors with potential value in micro-robotics applications. Specifically, the experiments permit the MTB cells to be directed along parallel or divergent trajectories, suppress their flagellar forces through magnetic means, and induce transitions between planar, circulating trajectories and drifting, vertically oriented ``top-like'' motion. The implications of the work for fundamental hydrodynamics research as well as bacterially driven robotics applications will be discussed.

Description and test results of a variable speed, constant frequency generating system

NASA Astrophysics Data System (ADS)

Brady, F. J.

1985-12-01

The variable-speed, constant frequency generating system developed for the Mod-0 wind turbine is presented. This report describes the system as it existed at the conclusion of the project. The cycloconverter control circuit is described including the addition of field-oriented control. The laboratory test and actual wind turbine test results are included.

Theoretical study of spin Hall effect in conjugated Organic semiconductors

NASA Astrophysics Data System (ADS)

Mahani, M. R.; Delin, A.

The spin Hall effect (SHE), a direct conversion between electronic and spin currents, is a rapidly growing branch of spintronics. The study of SHE in conjugated polymers has gained momentum recently due to the weak spin-orbit couplings and hyperfine interactions in these materials. Our calculations of SHE based on the recent work, are the result of the misalignment of pi-orbitals in triads consisting of three molecules. In disordered organics, where the electronic conduction is through hopping of the electrons among randomly oriented molecules, instead of identifying a hopping triad to represent the entire system, we numerically solve the master equations for electrical and spin hall conductivities by summing the contributions from all triads in a sufficiently large system. The interference between the direct and indirect hoppings in these triads leads to SHE proportional to the orientation vector of molecule at the first order of spin-orbit coupling. Hence, our results show, the degree of molecular alignment as well as the strength of the spin-orbit coupling can be used to control the SHE in organics.

Tomographic active optical trapping of arbitrarily shaped objects by exploiting 3D refractive index maps

NASA Astrophysics Data System (ADS)

Kim, Kyoohyun; Park, Yongkeun

2017-05-01

Optical trapping can manipulate the three-dimensional (3D) motion of spherical particles based on the simple prediction of optical forces and the responding motion of samples. However, controlling the 3D behaviour of non-spherical particles with arbitrary orientations is extremely challenging, due to experimental difficulties and extensive computations. Here, we achieve the real-time optical control of arbitrarily shaped particles by combining the wavefront shaping of a trapping beam and measurements of the 3D refractive index distribution of samples. Engineering the 3D light field distribution of a trapping beam based on the measured 3D refractive index map of samples generates a light mould, which can manipulate colloidal and biological samples with arbitrary orientations and/or shapes. The present method provides stable control of the orientation and assembly of arbitrarily shaped particles without knowing a priori information about the sample geometry. The proposed method can be directly applied in biophotonics and soft matter physics.

Magnetization reversal of in-plane uniaxial Co films and its dependence on epitaxial alignment

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

Idigoras, O., E-mail: o.idigoras@nanogune.eu; Suszka, A. K.; Berger, A.

2014-02-28

This work studies the influence of crystallographic alignment onto magnetization reversal in partially epitaxial Co films. A reproducible growth sequence was devised that allows for the continuous tuning of grain orientation disorder in Co films with uniaxial in-plane anisotropy by the controlled partial suppression of epitaxy. While all stable or meta-stable magnetization states occurring during a magnetic field cycle exhibit a uniform magnetization for fully epitaxial samples, non-uniform states appear for samples with sufficiently high grain orientation disorder. Simultaneously with the occurrence of stable domain states during the magnetization reversal, we observe a qualitative change of the applied field anglemore » dependence of the coercive field. Upon increasing the grain orientation disorder, we observe a disappearance of transient domain wall propagation as the dominating reversal process, which is characterized by an increase of the coercive field for applied field angles away from the easy axis for well-ordered epitaxial samples. Upon reaching a certain disorder threshold level, we also find an anomalous magnetization reversal, which is characterized by a non-monotonic behavior of the remanent magnetization and coercive field as a function of the applied field angle in the vicinity of the nominal hard axis. This anomaly is a collective reversal mode that is caused by disorder-induced frustration and it can be qualitatively and even quantitatively explained by means of a two Stoner-Wohlfarth particle model. Its predictions are furthermore corroborated by Kerr microscopy and by Brillouin light scattering measurements.« less

Cost-effectiveness of a long-term Internet-delivered worksite health promotion programme on physical activity and nutrition: a cluster randomized controlled trial

PubMed Central

Robroek, Suzan J. W.; Polinder, Suzanne; Bredt, Folef J.; Burdorf, Alex

2012-01-01

This study aims to evaluate the cost-effectiveness of a long-term workplace health promotion programme on physical activity (PA) and nutrition. In total, 924 participants enrolled in a 2-year cluster randomized controlled trial, with departments (n = 74) within companies (n = 6) as the unit of randomization. The intervention was compared with a standard programme consisting of a physical health check with face-to-face advice and personal feedback on a website. The intervention consisted of several additional website functionalities: action-oriented feedback, self-monitoring, possibility to ask questions and monthly e-mail messages. Primary outcomes were meeting the guidelines for PA and fruit and vegetable intake. Secondary outcomes were self-perceived health, obesity, elevated blood pressure, elevated cholesterol level and maximum oxygen uptake. Direct and indirect costs were calculated from a societal perspective, and a process evaluation was performed. Of the 924 participants, 72% participated in the first and 60% in the second follow-up. No statistically significant differences were found on primary and secondary outcomes, nor on costs. Average direct costs per participant over the 2-year period were €376, and average indirect costs were €9476. In conclusion, no additional benefits were found in effects or cost savings. Therefore, the programme in its current form cannot be recommended for implementation. PMID:22350194

Therapeutic alliance mediates the association between personality and treatment outcome in patients with major depressive disorder.

PubMed

Kushner, Shauna C; Quilty, Lena C; Uliaszek, Amanda A; McBride, Carolina; Bagby, R Michael

2016-09-01

Patient personality traits have been shown to influence treatment outcome in those with major depressive disorder (MDD). The trait agreeableness, which reflects an interpersonal orientation, may affect treatment outcome via its role in the formation of therapeutic alliance. No published studies have tested this hypothesis in patients with MDD. Participants were 209 outpatients with MDD who were treated in a randomized control trial. Mediation analyses were conducted to examine the role of therapeutic alliance in the association between pretreatment personality and the reduction of depression symptom severity during treatment. Separate models were estimated for patient- versus therapist-rated therapeutic alliance. We found a significant indirect effect of agreeableness on the reduction of depression severity via patient-rated therapeutic alliance. Results were replicated across two well-validated measures of depression symptom severity. Results also partially supported indirect effects for extraversion and openness. Therapist ratings of alliance did not mediate the association between personality and treatment outcomes. Patients were recruited as part of a randomized control trial, which may limit the generalizability of results to practice-based clinical settings. Due to constraints on statistical power, intervention-specific mediation results were not examined. These results highlight the importance of personality and the role it plays in treatment process as well as outcome. Copyright © 2016 Elsevier B.V. All rights reserved.

Optimization and validation of indirect ELISA using truncated TssB protein for the serodiagnosis of glanders amongst equines.

PubMed

Singha, Harisankar; Malik, Praveen; Goyal, Sachin K; Khurana, Sandip K; Mukhopadhyay, Chiranjay; Eshwara, Vandana K; Singh, Raj K

2014-01-01

To express truncated TssB protein of Burkholderia mallei and to evaluate its diagnostic efficacy for serological detection of glanders among equines. In an attempt to develop recombinant protein based enzyme-linked immunosorbent assay (ELISA), N-terminal 200 amino acid sequences of B. mallei TssB protein-a type 6 secretory effector protein--were expressed in prokaryotic expression system. Diagnostic potential of recombinant TssB protein was evaluated in indirect ELISA using a panel of glanders positive (n = 49), negative (n = 30), and field serum samples (n = 1811). Cross-reactivity of the assay was assessed with equine disease control serum and human melioidosis positive serum. In comparison to CFT, diagnostic sensitivity and specificity of ELISA were 99.7% and 100%, respectively. The indirect ELISA method using the truncated TssB offered safer and more rapid and efficient means of serodiagnosis of glanders in equines. These data highlight the use of TssB as potential diagnostic antigen for serological diagnosis of glanders.

Indirect interactions between invasive and native plants via pollinators

NASA Astrophysics Data System (ADS)

Kaiser-Bunbury, Christopher N.; Müller, Christine B.

2009-03-01

In generalised pollination systems, the presence of alien plant species may change the foraging behaviour of pollinators on native plant species, which could result in reduced reproductive success of native plant species. We tested this idea of indirect interactions on a small spatial and temporal scale in a field study in Mauritius, where the invasive strawberry guava, Psidium cattleianum, provides additional floral resources for insect pollinators. We predicted that the presence of flowering guava would indirectly and negatively affect the reproductive success of the endemic plant Bertiera zaluzania, which has similar flowers, by diverting shared pollinators. We removed P. cattleianum flowers within a 5-m radius from around half the B. zaluzania target plants (treatment) and left P. cattleianum flowers intact around the other half (control). By far, the most abundant and shared pollinator was the introduced honey bee, Apis mellifera, but its visitation rates to treatment and control plants were similar. Likewise, fruit and seed set and fruit size and weight of B. zaluzania were not influenced by the presence of P. cattleianum flowers. Although other studies have shown small-scale effects of alien plant species on neighbouring natives, we found no evidence for such negative indirect interactions in our system. The dominance of introduced, established A. mellifera indicates their replacement of native insect flower visitors and their function as pollinators of native plant species. However, the pollination effectiveness of A. mellifera in comparison to native pollinators is unknown.

Powder agglomeration in a microgravity environment

NASA Technical Reports Server (NTRS)

Cawley, James D.

1994-01-01

This is the final report for NASA Grant NAG3-755 entitled 'Powder Agglomeration in a Microgravity Environment.' The research program included both two types of numerical models and two types of experiments. The numerical modeling included the use of Monte Carlo type simulations of agglomerate growth including hydrodynamic screening and molecular dynamics type simulations of the rearrangement of particles within an agglomerate under a gravitational field. Experiments included direct observation of the agglomeration of submicron alumina and indirect observation, using small angle light scattering, of the agglomeration of colloidal silica and aluminum monohydroxide. In the former class of experiments, the powders were constrained to move on a two-dimensional surface oriented to minimize the effect of gravity. In the latter, some experiments involved mixture of suspensions containing particles of opposite charge which resulted in agglomeration on a very short time scale relative to settling under gravity.

Running away from stress: How regulatory modes prospectively affect athletes' stress through passion.

PubMed

Lucidi, F; Pica, G; Mallia, L; Castrucci, E; Manganelli, S; Bélanger, J J; Pierro, A

2016-06-01

A prospective field study conducted with runners training for an upcoming marathon (Marathon of Rome 2013) examined the relation between regulatory modes, locomotion and assessment, and stress. Integrating regulatory mode theory and the dualistic model of passion, we hypothesized that the relation between regulatory modes (evaluated 3 months before the race) and the experience of stress approaching the marathon, is mediated by the type of passion (harmonious vs obsessive) athletes experience with regard to marathoning. Results revealed that (a) locomotion positively predicted harmonious passion, which in turn reduced athletes' experience of stress; and (b) assessment positively predicted obsessive passion, which in turn enhanced athletes' experience of stress. Overall, the present results suggest that proximal psychological mechanisms such as basic regulatory mode orientations can predict distal outcomes such as stress indirectly through their relation with motivational phenomena such as passion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Moral Punishment in Everyday Life.

PubMed

Hofmann, Wilhelm; Brandt, Mark J; Wisneski, Daniel C; Rockenbach, Bettina; Skitka, Linda J

2018-05-01

The present research investigated event-related, contextual, demographic, and dispositional predictors of the desire to punish perpetrators of immoral deeds in daily life, as well as connections among the desire to punish, moral emotions, and momentary well-being. The desire to punish was reliably predicted by linear gradients of social closeness to both the perpetrator (negative relationship) and the victim (positive relationship). Older rather than younger adults, conservatives rather than people with other political orientations, and individuals high rather than low in moral identity desired to punish perpetrators more harshly. The desire to punish was related to state anger, disgust, and embarrassment, and these were linked to lower momentary well-being. However, the negative effect of these emotions on well-being was partially compensated by a positive indirect pathway via heightened feelings of moral self-worth. Implications of the present field data for moral punishment research and the connection between morality and well-being are discussed.

Time Evolution of the Density Field of a Micro-Explosion Using Background Oriented Schlieren

NASA Astrophysics Data System (ADS)

Suriyanarayanan, P.; Venkatakrishnan, L.; Jagadeesh, G.

In recent years micro-explosions have found interesting trans-disciplinary applications in the areas of food preservation,wood science, drug delivery, gene therapy and bio-medical applications [1, 2]. Generating controlled micro-explosions in a laboratory environment in a reliable manner is essential; to study and understand some of the near field flow dynamics associated with blast waves.

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system.

PubMed

Mumtaz, Sidra; Khan, Laiq; Ahmed, Saghir; Bader, Rabiah

2017-01-01

This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms.

Indirect adaptive soft computing based wavelet-embedded control paradigms for WT/PV/SOFC in a grid/charging station connected hybrid power system

PubMed Central

Khan, Laiq; Ahmed, Saghir; Bader, Rabiah

2017-01-01

This paper focuses on the indirect adaptive tracking control of renewable energy sources in a grid-connected hybrid power system. The renewable energy systems have low efficiency and intermittent nature due to unpredictable meteorological conditions. The domestic load and the conventional charging stations behave in an uncertain manner. To operate the renewable energy sources efficiently for harvesting maximum power, instantaneous nonlinear dynamics should be captured online. A Chebyshev-wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control paradigm is proposed for variable speed wind turbine-permanent synchronous generator (VSWT-PMSG). A Hermite-wavelet incorporated NeuroFuzzy indirect adaptive MPPT control strategy for photovoltaic (PV) system to extract maximum power and indirect adaptive tracking control scheme for Solid Oxide Fuel Cell (SOFC) is developed. A comprehensive simulation test-bed for a grid-connected hybrid power system is developed in Matlab/Simulink. The robustness of the suggested indirect adaptive control paradigms are evaluated through simulation results in a grid-connected hybrid power system test-bed by comparison with conventional and intelligent control techniques. The simulation results validate the effectiveness of the proposed control paradigms. PMID:28877191

Towards an Approach of Semantic Access Control for Cloud Computing

NASA Astrophysics Data System (ADS)

Hu, Luokai; Ying, Shi; Jia, Xiangyang; Zhao, Kai

With the development of cloud computing, the mutual understandability among distributed Access Control Policies (ACPs) has become an important issue in the security field of cloud computing. Semantic Web technology provides the solution to semantic interoperability of heterogeneous applications. In this paper, we analysis existing access control methods and present a new Semantic Access Control Policy Language (SACPL) for describing ACPs in cloud computing environment. Access Control Oriented Ontology System (ACOOS) is designed as the semantic basis of SACPL. Ontology-based SACPL language can effectively solve the interoperability issue of distributed ACPs. This study enriches the research that the semantic web technology is applied in the field of security, and provides a new way of thinking of access control in cloud computing.

Retinal ganglion cell dendritic fields in old-world monkeys are oriented radially.

PubMed

Schall, J D; Perry, V H; Leventhal, A G

1986-03-12

We analyzed the dendritic field morphology of 297 ganglion cells from peripheral regions of monkey retina. Most of the dendritic fields were elongated, and there was a significant tendency for the dendritic fields to be oriented radially, i.e., like the spokes of a wheel with the fovea at the hub. An overrepresentation of radial orientations in the peripheral retina of primates might explain why humans are best able to detect stimuli which are oriented radially using peripheral vision.

Direct Torque Control of a Three-Phase Voltage Source Inverter-Fed Induction Machine

DTIC Science & Technology

2013-12-01

factors, FOC acquires all advantages of DC machine control and frees itself from the mechanical commutation drawbacks. Furthermore, FOC leads to high...of three-phase induction motor using microcontroller,” S.R.M Engineering College, Tamil Nadu, India , June/July 2006. [5] Texas Instruments Europe...loop. Direct flux control is possible through the constant magnetic field orientation achieved through commutator action. These two primary factors

Self-shaping composites with programmable bioinspired microstructures.

PubMed

Erb, Randall M; Sander, Jonathan S; Grisch, Roman; Studart, André R

2013-01-01

Shape change is a prevalent function apparent in a diverse set of natural structures, including seed dispersal units, climbing plants and carnivorous plants. Many of these natural materials change shape by using cellulose microfibrils at specific orientations to anisotropically restrict the swelling/shrinkage of their organic matrices upon external stimuli. This is in contrast to the material-specific mechanisms found in synthetic shape-memory systems. Here we propose a robust and universal method to replicate this unusual shape-changing mechanism of natural systems in artificial bioinspired composites. The technique is based upon the remote control of the orientation of reinforcing inorganic particles within the composite using a weak external magnetic field. Combining this reinforcement orientational control with swellable/shrinkable polymer matrices enables the creation of composites whose shape change can be programmed into the material's microstructure rather than externally imposed. Such bioinspired approach can generate composites with unusual reversibility, twisting effects and site-specific programmable shape changes.

Self-shaping composites with programmable bioinspired microstructures

NASA Astrophysics Data System (ADS)

Erb, Randall M.; Sander, Jonathan S.; Grisch, Roman; Studart, André R.

2013-04-01

Shape change is a prevalent function apparent in a diverse set of natural structures, including seed dispersal units, climbing plants and carnivorous plants. Many of these natural materials change shape by using cellulose microfibrils at specific orientations to anisotropically restrict the swelling/shrinkage of their organic matrices upon external stimuli. This is in contrast to the material-specific mechanisms found in synthetic shape-memory systems. Here we propose a robust and universal method to replicate this unusual shape-changing mechanism of natural systems in artificial bioinspired composites. The technique is based upon the remote control of the orientation of reinforcing inorganic particles within the composite using a weak external magnetic field. Combining this reinforcement orientational control with swellable/shrinkable polymer matrices enables the creation of composites whose shape change can be programmed into the material’s microstructure rather than externally imposed. Such bioinspired approach can generate composites with unusual reversibility, twisting effects and site-specific programmable shape changes.

Directed block copolymer self-assembly implemented via surface-embedded electrets

NASA Astrophysics Data System (ADS)

Wu, Mei-Ling; Wang, Dong; Wan, Li-Jun

2016-02-01

Block copolymer (BCP) nanolithography is widely recognized as a promising complementary approach to circumvent the feature size limits of conventional photolithography. The directed self-assembly of BCP thin film to form ordered nanostructures with controlled orientation and localized pattern has been the key challenge for practical nanolithography applications. Here we show that BCP nanopatterns can be directed on localized surface electrets defined by electron-beam irradiation to realize diverse features in a simple, effective and non-destructive manner. Charged electrets can generate a built-in electric field in BCP thin film and induce the formation of perpendicularly oriented microdomain of BCP film. The electret-directed orientation control of BCP film can be either integrated with mask-based patterning technique or realized by electron-beam direct-writing method to fabricate microscale arbitrary lateral patterns down to single BCP cylinder nanopattern. The electret-directed BCP self-assembly could provide an alternative means for BCP-based nanolithography, with high resolution.

Magnetic field stabilized electron-hole liquid in indirect-band-gap A l x G a 1 - x As

DOE PAGES

Alberi, K.; Fluegel, B.; Crooker, S. A.; ...

2016-02-29

An electron-hole liquid (EHL), a condensed liquidlike phase of free electrons and holes in a semiconductor, presents a unique system for exploring quantum many-body phenomena. And while the behavior of EHLs is generally understood, less attention has been devoted to systematically varying the onset of their formation and resulting properties. Here, we report on an experimental approach to tune the conditions of formation and characteristics using a combination of low excitation densities and high magnetic fields up to 90 T. Demonstration of this approach was carried out in indirect-band-gap A l 0.387 G a 0.613 As . EHL droplets canmore » be nucleated from one of two multiexciton complex states depending on the applied excitation density. Furthermore, the excitation density influences the carrier density of the EHL at high magnetic fields, where filling of successive Landau levels can be controlled. The ability to manipulate the formation pathway, temperature, and carrier density of the EHL phase under otherwise fixed experimental conditions makes our approach a powerful tool for studying condensed carrier phases in further detail.« less

College Students' Social Goals and Psychological Adjustment: Mediation via Emotion Regulation

ERIC Educational Resources Information Center

Shim, Sungok Serena; Wang, Cen; Makara, Kara A.; Xu, Xiao-Guang; Xie, Li-Na; Zhong, Ming

2017-01-01

University life can be stressful and students may struggle to adjust socially. We examined students' social achievement goals--their orientations towards their relationships with their peers--as one important factor underlying students' social and psychological adjustment in college. When investigating the direct and indirect effects of social…

A conditioned visual orientation requires the ellipsoid body in Drosophila

PubMed Central

Guo, Chao; Du, Yifei; Yuan, Deliang; Li, Meixia; Gong, Haiyun; Gong, Zhefeng

2015-01-01

Orientation, the spatial organization of animal behavior, is an essential faculty of animals. Bacteria and lower animals such as insects exhibit taxis, innate orientation behavior, directly toward or away from a directional cue. Organisms can also orient themselves at a specific angle relative to the cues. In this study, using Drosophila as a model system, we established a visual orientation conditioning paradigm based on a flight simulator in which a stationary flying fly could control the rotation of a visual object. By coupling aversive heat shocks to a fly's orientation toward one side of the visual object, we found that the fly could be conditioned to orientate toward the left or right side of the frontal visual object and retain this conditioned visual orientation. The lower and upper visual fields have different roles in conditioned visual orientation. Transfer experiments showed that conditioned visual orientation could generalize between visual targets of different sizes, compactness, or vertical positions, but not of contour orientation. Rut—Type I adenylyl cyclase and Dnc—phosphodiesterase were dispensable for visual orientation conditioning. Normal activity and scb signaling in R3/R4d neurons of the ellipsoid body were required for visual orientation conditioning. Our studies established a visual orientation conditioning paradigm and examined the behavioral properties and neural circuitry of visual orientation, an important component of the insect's spatial navigation. PMID:25512578

Numerical study of insect free hovering flight

NASA Astrophysics Data System (ADS)

Wu, Di; Yeo, Khoon Seng; Lim, Tee Tai; Fluid lab, Mechanical Engineering, National University of Singapore Team

2012-11-01

In this paper we present the computational fluid dynamics study of three-dimensional flow field around a free hovering fruit fly integrated with unsteady FSI analysis and the adaptive flight control system for the first time. The FSI model being specified for fruitfly hovering is achieved by coupling a structural problem based on Newton's second law with a rigorous CFD solver concerning generalized finite difference method. In contrast to the previous hovering flight research, the wing motion employed here is not acquired from experimental data but governed by our proposed control systems. Two types of hovering control strategies i.e. stroke plane adjustment mode and paddling mode are explored, capable of generating the fixed body position and orientation characteristic of hovering flight. Hovering flight associated with multiple wing kinematics and body orientations are shown as well, indicating the means by which fruitfly actually maintains hovering may have considerable freedom and therefore might be influenced by many other factors beyond the physical and aerodynamic requirements. Additionally, both the near- and far-field flow and vortex structure agree well with the results from other researchers, demonstrating the reliability of our current model.

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Companies Interpretations § 225.112 Indirect control of small business concern through convertible...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 3 2014-01-01 2014-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Companies Interpretations § 225.112 Indirect control of small business concern through convertible...

High-temperature superconducting radiofrequency probe for magnetic resonance imaging applications operated below ambient pressure in a simple liquid-nitrogen cryostat

NASA Astrophysics Data System (ADS)

Lambert, Simon; Ginefri, Jean-Christophe; Poirier-Quinot, Marie; Darrasse, Luc

2013-05-01

The present work investigates the joined effects of temperature and static magnetic field on the electrical properties of a 64 MHz planar high-temperature superconducting (HTS) coil, in order to enhance the signal-to-noise ratio (SNR) in nuclear magnetic resonance (NMR) applications with a moderate decrease of the HTS coil temperature (THTS). Temperature control is provided with accuracy better than 0.1 K from 80 to 66 K by regulating the pressure of the liquid nitrogen bath of a dedicated cryostat. The actual temperature of the HTS coil is obtained using a straightforward wireless method that eliminates the risks of coupling electromagnetic interference to the HTS coil and of disturbing the static magnetic field by DC currents near the region of interest. The resonance frequency ( f0) and the quality factor (Q) of the HTS coil are measured as a function of temperature in the 0-4.7 T field range with parallel and orthogonal orientations relative to the coil plane. The intrinsic HTS coil sensitivity and the detuning effect are then analyzed from the Q and f0 data. In the presence of the static magnetic field, the initial value of f0 in Earth's field could be entirely recovered by decreasing THTS, except for the orthogonal orientation above 1 T. The improvement of Q by lowering THTS was substantial. From 80 to 66 K, Q was multiplied by a factor of 6 at 1.5 T in orthogonal orientation. In parallel orientation, the maximum measured improvement of Q from 80 K to 66 K was a factor of 2. From 80 to 66 K, the improvement of the RF sensitivity relative to the initial value at the Earth's field and ambient pressure was up to 4.4 dB in parallel orientation. It was even more important in orthogonal orientation and continued to increase, up to 8.4 dB, at the maximum explored field of 1.5 T. Assuming that the noise contributions from the RF receiver are negligible, the SNR improvement using enhanced HTS coil cooling in NMR experiments was extracted from Q measurements either with or without the presence of the sample. Notably, the additional cooling in the presence of conductive samples appears more beneficial at higher field strengths and with an orthogonal incidence than with parallel. The temperature range accessible here, involving a relatively straightforward cryogenic design, brings a gain in RF sensitivity that is of great significance to cutting-edge applications with very weakly conducting samples, small biological specimens, or small animals in vivo. This work also demonstrates a better tolerance to thin-film orientation misalignments relative to the magnetic field, and this could eventually play a role in designing effective non-planar HTS coils or coil arrays which include elements of various orientations. Finally, the data provided in this work may help understand some critical aspects in the design of HTS coils for NMR and MRI applications and accounts for the presence of the static magnetic field, particularly regarding the SNR loss due to a decreased quality factor and detuning issues.

Blindsight modulation of motion perception.

PubMed

Intriligator, James M; Xie, Ruiman; Barton, Jason J S

2002-11-15

Monkey data suggest that of all perceptual abilities, motion perception is the most likely to survive striate damage. The results of studies on motion blindsight in humans, though, are mixed. We used an indirect strategy to examine how responses to visible stimuli were modulated by blind-field stimuli. In a 26-year-old man with focal striate lesions, discrimination of visible optic flow was enhanced about 7% by blind-field flow, even though discrimination of optic flow in the blind field alone (the direct strategy) was at chance. Pursuit of an imagined target using peripheral cues showed reduced variance but not increased gain with blind-field cues. Preceding blind-field prompts shortened reaction times to visible targets by about 10 msec, but there was no attentional crowding of visible stimuli by blind-field distractors. A similar efficacy of indirect blind-field optic flow modulation was found in a second patient with residual vision after focal striate damage, but not in a third with more extensive medial occipito-temporal damage. We conclude that indirect modulatory strategies are more effective than direct forced-choice methods at revealing residual motion perception after focal striate lesions.

Driving with indirect viewing sensors: understanding the visual perception issues

NASA Astrophysics Data System (ADS)

O'Kane, Barbara L.

1996-05-01

Visual perception is one of the most important elements of driving in that it enables the driver to understand and react appropriately to the situation along the path of the vehicle. The visual perception of the driver is enabled to the greatest extent while driving during the day. Noticeable decrements in visual acuity, range of vision, depth of field and color perception occur at night and under certain weather conditions. Indirect viewing sensors, utilizing various technologies and spectral bands, may assist the driver's normal mode of driving. Critical applications in the military as well as other official activities may require driving at night without headlights. In these latter cases, it is critical that the device, being the only source of scene information, provide the required scene cues needed for driving on, and often-times, off road. One can speculate about the scene information that a driver needs, such as road edges, terrain orientation, people and object detection in or near the path of the vehicle, and so on. But the perceptual qualities of the scene that give rise to these perceptions are little known and thus not quantified for evaluation of indirect viewing devices. This paper discusses driving with headlights and compares the scene content with that provided by a thermal system in the 8 - 12 micrometers micron spectral band, which may be used for driving at some time. The benefits and advantages of each are discussed as well as their limitations in providing information useful for the driver who must make rapid and critical decisions based upon the scene content available. General recommendations are made for potential avenues of development to overcome some of these limitations.

Integration of bioinformatics into an undergraduate biology curriculum and the impact on development of mathematical skills.

PubMed

Wightman, Bruce; Hark, Amy T

2012-01-01

The development of fields such as bioinformatics and genomics has created new challenges and opportunities for undergraduate biology curricula. Students preparing for careers in science, technology, and medicine need more intensive study of bioinformatics and more sophisticated training in the mathematics on which this field is based. In this study, we deliberately integrated bioinformatics instruction at multiple course levels into an existing biology curriculum. Students in an introductory biology course, intermediate lab courses, and advanced project-oriented courses all participated in new course components designed to sequentially introduce bioinformatics skills and knowledge, as well as computational approaches that are common to many bioinformatics applications. In each course, bioinformatics learning was embedded in an existing disciplinary instructional sequence, as opposed to having a single course where all bioinformatics learning occurs. We designed direct and indirect assessment tools to follow student progress through the course sequence. Our data show significant gains in both student confidence and ability in bioinformatics during individual courses and as course level increases. Despite evidence of substantial student learning in both bioinformatics and mathematics, students were skeptical about the link between learning bioinformatics and learning mathematics. While our approach resulted in substantial learning gains, student "buy-in" and engagement might be better in longer project-based activities that demand application of skills to research problems. Nevertheless, in situations where a concentrated focus on project-oriented bioinformatics is not possible or desirable, our approach of integrating multiple smaller components into an existing curriculum provides an alternative. Copyright © 2012 Wiley Periodicals, Inc.

Control of vortex state in cobalt nanorings with domain wall pinning centers

NASA Astrophysics Data System (ADS)

Lal, Manohar; Sakshath, S.; Mohanan Parakkat, Vineeth; Anil Kumar, P. S.

2018-05-01

Magnetic rings at the mesoscopic scale exhibit new spin configuration states and switching behavior, which can be controlled via geometrical structure, material composition and applied field. Vortex states in magnetic nanorings ensure flux closure, which is necessary for low stray fields in high packing density in memory devices. We performed magnetoresistance measurements on cobalt nanoring devices and show that by attaching nanowires to the ring, the vortex state can be stabilized. When a square pad is attached to the free end of the wire, the domain wall nucleation field in the nanowire is reduced. In addition, the vortex state persists over a larger range of magnetic fields, and exists at all in-plane orientations of the magnetic field. These experimental findings are well supported by our micromagnetic simulations.

The Positive Effect of Authoritarian Leadership on Employee Performance: The Moderating Role of Power Distance.

PubMed

Wang, Honglei; Guan, Bichen

2018-01-01

Based on goal setting theory, this study explores the positive effect and influencing process of authoritarian leadership on employee performance, as well as the moderating role of individual power distance in this process. Data from 211 supervisor-subordinate dyads in Chinese organizations indicates that authoritarian leadership is positively associated with employee performance, and learning goal orientation mediates this relationship. Furthermore, power distance moderates the effect of authoritarian leadership on learning goal orientation, such that the effect was stronger when individual power distance was higher. The indirect effect of authoritarian leadership on employee performance via learning goal orientation is also moderated by power distance. Theoretical and managerial implications and future directions are also discussed.

The Positive Effect of Authoritarian Leadership on Employee Performance: The Moderating Role of Power Distance

PubMed Central

Wang, Honglei; Guan, Bichen

2018-01-01

Based on goal setting theory, this study explores the positive effect and influencing process of authoritarian leadership on employee performance, as well as the moderating role of individual power distance in this process. Data from 211 supervisor-subordinate dyads in Chinese organizations indicates that authoritarian leadership is positively associated with employee performance, and learning goal orientation mediates this relationship. Furthermore, power distance moderates the effect of authoritarian leadership on learning goal orientation, such that the effect was stronger when individual power distance was higher. The indirect effect of authoritarian leadership on employee performance via learning goal orientation is also moderated by power distance. Theoretical and managerial implications and future directions are also discussed. PMID:29628902

Compensation for positioning error of industrial robot for flexible vision measuring system

NASA Astrophysics Data System (ADS)

Guo, Lei; Liang, Yajun; Song, Jincheng; Sun, Zengyu; Zhu, Jigui

2013-01-01

Positioning error of robot is a main factor of accuracy of flexible coordinate measuring system which consists of universal industrial robot and visual sensor. Present compensation methods for positioning error based on kinematic model of robot have a significant limitation that it isn't effective in the whole measuring space. A new compensation method for positioning error of robot based on vision measuring technique is presented. One approach is setting global control points in measured field and attaching an orientation camera to vision sensor. Then global control points are measured by orientation camera to calculate the transformation relation from the current position of sensor system to global coordinate system and positioning error of robot is compensated. Another approach is setting control points on vision sensor and two large field cameras behind the sensor. Then the three dimensional coordinates of control points are measured and the pose and position of sensor is calculated real-timely. Experiment result shows the RMS of spatial positioning is 3.422mm by single camera and 0.031mm by dual cameras. Conclusion is arithmetic of single camera method needs to be improved for higher accuracy and accuracy of dual cameras method is applicable.

Application of Volatile Antifungal Plant Essential Oils for Controlling Pepper Fruit Anthracnose by Colletotrichum gloeosporioides.

PubMed

Hong, Jeum Kyu; Yang, Hye Ji; Jung, Heesoo; Yoon, Dong June; Sang, Mee Kyung; Jeun, Yong-Chull

2015-09-01

Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for eco-friendly disease management of anthracnose during pepper fruit production.

Instabilities, rheology and spontaneous flows in magnetotactic bacterial suspensions

NASA Astrophysics Data System (ADS)

Alonso-Matilla, Roberto; Saintillan, David

2017-11-01

Magnetotactic bacteria are motile prokaryotes, mostly present in marine habitats, that synthesize intracellular magnetic membrane-bounded crystals known as magnetosomes. They behave as self-propelled permanent magnetic dipoles that orient and migrate along the geomagnetic field lines of the Earth. In this work, we analyze the macroscopic transport properties of suspensions of such bacteria in microfluidic devices. When placed in an external magnetic field, these microorganisms feel a net magnetic torque which is transmitted to the surrounding fluid, and can give rise to a net unidirectional fluid flow in a planar channel, with a flow rate and direction that can be controlled by adjusting both the magnitude and orientation of the external field. Using a continuum kinetic model, we provide a physical explanation for the onset of these spontaneous flows. We also study the rheological properties and stability of these suspensions in both an applied shear flow and a pressure-driven flow.

Phonon-assisted indirect transitions in angle-resolved photoemission spectra of graphite and graphene

NASA Astrophysics Data System (ADS)

Ayria, Pourya; Tanaka, Shin-ichiro; Nugraha, Ahmad R. T.; Dresselhaus, Mildred S.; Saito, Riichiro

2016-08-01

Indirect transitions of electrons in graphene and graphite are investigated by means of angle-resolved photoemission spectroscopy (ARPES) with several different incident photon energies and light polarizations. The theoretical calculations of the indirect transition for graphene and for a single crystal of graphite are compared with the experimental measurements for highly-oriented pyrolytic graphite and a single crystal of graphite. The dispersion relations for the transverse optical (TO) and the out-of-plane longitudinal acoustic (ZA) phonon modes of graphite and the TO phonon mode of graphene can be extracted from the inelastic ARPES intensity. We find that the TO phonon mode for k points along the Γ -K and K -M -K' directions in the Brillouin zone can be observed in the ARPES spectra of graphite and graphene by using a photon energy ≈11.1 eV. The relevant mechanism in the ARPES process for this case is the resonant indirect transition. On the other hand, the ZA phonon mode of graphite can be observed by using a photon energy ≈6.3 eV through a nonresonant indirect transition, while the ZA phonon mode of graphene within the same mechanism should not be observed.

Bias Dependent Spin Relaxation in a [110]-InAs/AlSb Two Dimensional Electron System

NASA Astrophysics Data System (ADS)

Hicks, J.; Holabird, K.

2005-03-01

Manipulation of electron spin is a critical component of many proposed semiconductor spintronic devices. One promising approach utilizes the Rashba effect by which an applied electric field can be used to reduce the spin lifetime or rotate spin orientation through spin-orbit interaction. The large spin-orbit interaction needed for this technique to be effective typically leads to fast spin relaxation through precessional decay, which may severely limit device architectures and functionalities. An exception arises in [110]-oriented heterostructures where the crystal magnetic field associated with bulk inversion asymmetry lies along the growth direction and in which case spins oriented along the growth direction do not precess. These considerations have led to a recent proposal of a spin-FET that incorporates a [110]-oriented, gate-controlled InAs quantum well channel [1]. We report measurements of the electron spin lifetime as a function of applied electric field in a [110]-InAs 2DES. Measurements made using an ultrafast, mid-IR pump-probe technique indicate that the spin lifetime can be reduced from its maximum to minimum value over a range of less than 0.2V per quantum well at room temperature. This work is supported by DARPA, NSERC and the NSF grant ECS - 0322021. [1] K. C. Hall, W. H. Lau, K. Gundogdu, M. E. Flatte, and T. F. Boggess, Appl. Phys. Lett. 83, 2937 (2003).

The Micromechanics of the Moving Contact Line

NASA Technical Reports Server (NTRS)

Han, Minsub; Lichter, Seth; Lin, Chih-Yu; Perng, Yeong-Yan

1996-01-01

The proposed research is divided into three components concerned with molecular structure, molecular orientation, and continuum averages of discrete systems. In the experimental program, we propose exploring how changes in interfacial molecular structure generate contact line motion. Rather than rely on the electrostatic and electrokinetic fields arising from the molecules themselves, we augment their interactions by an imposed field at the solid/liquid interface. By controling the field, we can manipulate the molecular structure at the solid/liquid interface. In response to controlled changes in molecular structure, we observe the resultant contact line motion. In the analytical portion of the proposed research we seek to formulate a system of equations governing fluid motion which accounts for the orientation of fluid molecules. In preliminary work, we have focused on describing how molecular orientation affects the forces generated at the moving contact line. Ideally, as assumed above, the discrete behavior of molecules can be averaged into a continuum theory. In the numerical portion of the proposed research, we inquire whether the contact line region is, in fact, large enough to possess a well-defined average. Additionally, we ask what types of behavior distinguish discrete systems from continuum systems. Might the smallness of the contact line region, in itself, lead to behavior different from that in the bulk? Taken together, our proposed research seeks to identify and accurately account for some of the molecular dynamics of the moving contact line, and attempts to formulate a description from which one can compute the forces at the moving contact line.

Light intensity modulation by coccoliths of Emiliania huxleyi as a micro-photo-regulator.

PubMed

Mizukawa, Yuri; Miyashita, Yuito; Satoh, Manami; Shiraiwa, Yoshihiro; Iwasaka, Masakazu

2015-09-01

In this study, we present experimental evidence showing that coccoliths have light-scattering anisotropy that contributes to a possible control of solar light exposure in the ocean. Changing the angle between the incident light and an applied magnetic field causes differences in the light-scattering intensities of a suspension of coccoliths isolated from Emiliania huxleyi. The magnetic field effect is induced by the diamagnetic torque force directing the coccolith radial plane perpendicular to the applied magnetic fields at 400 to 500 mT. The developed technique reveals the light-scattering anisotropies in the 3-μm-diameter floating coccoliths by orienting themselves in response to the magnetic fields. The detached coccolith scatters radially the light incident to its radial plane. The experimental results on magnetically oriented coccoliths show that an individual coccolith has a specific direction of light scattering, although the possible physiological effect of the coccolith remains for further study, focusing on the light-scattering anisotropies of coccoliths on living cells.

Light intensity modulation by coccoliths of Emiliania huxleyi as a micro-photo-regulator

NASA Astrophysics Data System (ADS)

Mizukawa, Yuri; Miyashita, Yuito; Satoh, Manami; Shiraiwa, Yoshihiro; Iwasaka, Masakazu

2015-09-01

In this study, we present experimental evidence showing that coccoliths have light-scattering anisotropy that contributes to a possible control of solar light exposure in the ocean. Changing the angle between the incident light and an applied magnetic field causes differences in the light-scattering intensities of a suspension of coccoliths isolated from Emiliania huxleyi. The magnetic field effect is induced by the diamagnetic torque force directing the coccolith radial plane perpendicular to the applied magnetic fields at 400 to 500 mT. The developed technique reveals the light-scattering anisotropies in the 3-μm-diameter floating coccoliths by orienting themselves in response to the magnetic fields. The detached coccolith scatters radially the light incident to its radial plane. The experimental results on magnetically oriented coccoliths show that an individual coccolith has a specific direction of light scattering, although the possible physiological effect of the coccolith remains for further study, focusing on the light-scattering anisotropies of coccoliths on living cells.

Direct and indirect measurement of physical activity in older adults: a systematic review of the literature.

PubMed

Kowalski, Kristina; Rhodes, Ryan; Naylor, Patti-Jean; Tuokko, Holly; MacDonald, Stuart

2012-12-18

Due to physiological and cognitive changes that occur with aging, accurate physical activity (PA) measurement in older adults represents a unique challenge. The primary purpose of this study was to systematically review measures of PA and their use and appropriateness with older adults. A secondary aim was to determine the level of agreement between PA measures in older adults. Literature was identified through electronic databases. Studies were eligible if they examined the correlation and/or agreement between at least 2 measures, either indirect and/or direct, of PA in older adults (> 65 years of age). Thirty-six studies met eligibility criteria. The indirect and direct measures of PA across the studies differed widely in their ability to address the key dimensions (i.e., frequency, intensity, time, type) of PA in older adults. The average correlation between indirect and direct measures was moderate (r=0.38). The correlation between indirect and other indirect measures (r=0.29) was weak, while correlations between direct measures with other direct measures were high (real world: r= 0.84; controlled settings: r=0.92). Agreement was strongest between direct PA measures with other direct measures in both real world and laboratory settings. While a clear trend regarding the agreement for mean differences between other PA measures (i.e., direct with indirect, indirect with indirect) did not emerge, there were only a limited number of studies that reported comparable units. Despite the lack of a clear trend regarding the agreement between PA measures in older adults, the findings underscore the importance of valid, accurate and reliable measurement. To advance this field, researchers will need to approach the assessment of PA in older adults in a more standardized way (i.e., consistent reporting of results, consensus over cut-points and epoch lengths, using appropriate validation tools). Until then researchers should be cautious when choosing measures for PA that are appropriate for their research questions and when comparing PA levels across various studies.

Mesenchymal stem cells restore orientation and exploratory behavior of rats after brain injury.

PubMed

Sokolova, I B; Fedotova, O R; Tsikunov, S G; Polyntsev, D G

2011-05-01

We studied the effects of intravenous and intracerebral transplantation of MSC on restoration of orientation and exploratory behavior of Wistar-Kyoto rats after removal of the left motor cortex. Removal of the motor cortex led to a significant reduction of the number of behavioral acts in the open field test. Two weeks after removal of the motor cortex and intravenous transplantation, the animals were as inhibited as the controls, but during the next 10 weeks, the behavioral status of these rats remained unchanged, while controls exhibited further behavioral degradation. After injection of MSC into the brain, the behavior of rats with trauma did not change in comparison with intact rats over 10 weeks.

[Morphometry of giant multipolar neurons of the brain stem reticular formation in rats on board the Kosmos-1667 biosatellite].

PubMed

Belichenko, P V; Leontovich, T A

1989-05-01

Giant multipolar neurons of nucleus reticularis gigantocellularis of rats which had been kept on board the biosatellite "Kosmos-1667" were morphometrically studied. There was a trend towards the increase in the cellular surface, the maximum diameter of dendritic field, the volume of the whole dendritic territory in the test group ad in the control experimental group kept on the earth. A reliable decrease in dendritic mass oriented to nucleus vestibularis and an increase in dendritic mass oriented to the midline were also found in test group, as compared to 3 control groups. Our data were discussed in the light of nervous tissue plasticity in adult mammals.

Consumptive use and resulting leach-field water budget of a mountain residence

USGS Publications Warehouse

Stannard, David; Paul, William T.; Laws, Roy; Poeter, Eileen P.

2010-01-01

Consumptive use of water in a dispersed rural community has important implications for maximum housing density and its effects on sustainability of groundwater withdrawals. Recent rapid growth in Colorado, USA has stressed groundwater supplies in some areas, thereby increasing scrutiny of approximate methods developed there more than 30 years ago to estimate consumptive use that are still used today. A foothills residence was studied during a 2-year period to estimate direct and indirect water losses. Direct losses are those from evaporation inside the home, plus any outdoor use. Indirect loss is evapotranspiration (ET) from the residential leach-field in excess of ET from the immediately surrounding terrain. Direct losses were 18.7% of water supply to the home, substantially larger than estimated historically in Colorado. A new approach was developed to estimate indirect loss, using chamber methods together with the Penman–Monteith model. Indirect loss was only 0.9% of water supply, but this value probably was anomalously low due to a recurring leach-field malfunction. Resulting drainage beneath the leach-field was 80.4% of water supply. Guidelines are given to apply the same methodology at other sites and combine results with a survey of leach-fields in an area to obtain more realistic average values of ET losses.

Speed control of an induction motor by 6-switched 3-level inverter

NASA Astrophysics Data System (ADS)

Saygin, Ali; Kerem, Alper

2017-12-01

This paper presents speed control analysis of an induction motor by a 6-switched 3-level inverter. In the analysis of topology, the study used the field oriented control technique which is widely used in the literature, easy and stable for operating systems. The field weaking technique was used for speeds exceeding nominal speed to reduce magnetic saturation and thermal losses. At the end of the process, it was observed to increase motor torque and inverter efficiency. Instead of using 12 switches in conventional 3-level inverters, 6 switches are used in this topology. Reduced number of switches is the greatest contribution of this study.

Tuning bacterial hydrodynamics with magnetic fields

NASA Astrophysics Data System (ADS)

Pierce, C. J.; Mumper, E.; Brown, E. E.; Brangham, J. T.; Lower, B. H.; Lower, S. K.; Yang, F. Y.; Sooryakumar, R.

2017-06-01

Magnetotactic bacteria are a group of motile prokaryotes that synthesize chains of lipid-bound, magnetic nanoparticles called magnetosomes. This study exploits their innate magnetism to investigate previously unexplored facets of bacterial hydrodynamics at surfaces. Through use of weak, uniform, external magnetic fields and local, micromagnetic surface patterns, the relative strength of hydrodynamic, magnetic, and flagellar force components is tuned through magnetic control of the bacteria's orientation. The resulting swimming behaviors provide a means to experimentally determine hydrodynamic parameters and offer a high degree of control over large numbers of living microscopic entities. The implications of this controlled motion for studies of bacterial motility near surfaces and for micro- and nanotechnology are discussed.

Use of Field Observations for Understanding Controls of Polar Low Cloud Microphysical Properties

NASA Astrophysics Data System (ADS)

McFarquhar, G. M.

2016-12-01

Although arctic clouds have a net warming effect on the Arctic surface, their radiative effect is sensitive to cloud microphysical properties, namely the sizes, phases and shapes of cloud particles. Such cloud properties are influenced by the numbers, compositions and sizes of aerosols, meteorological conditions, and surface characteristics. Uncertainty in representing cloud-aerosol interactions in varying environmental conditions and associated feedbacks is a major cause in our lack of understanding of why the Arctic is warming faster than the rest of the Earth. Here, the understanding of cloud-aerosol interactions gained from past arctic field experiments is reviewed. Such studies have characterized the structure of single-layer mixed phase clouds that are ubiquitous in the Arctic and investigated different aerosol indirect effect mechanisms acting in these clouds. But, it is still unknown what controls the amount of supercooled water in arctic clouds (especially in complex frequently occurring multi-layer clouds), how probability distributions of cloud properties and radiative heating and their subsequent impact on temperature profiles and underlying snow and sea ice cover vary with aerosol loading and composition in different surface and meteorological conditions, how the composition and concentration of arctic aerosols and cloud microphysical properties vary annually and interannually, and how cloud-aerosol-radiative interactions can be better represented in models with varying temporal and spatial scales. These needs can be addressed in two ways. First, there is a need for comprehensive and routine aircraft, UAV and tethered balloon measurements in the presence of ground, air or space-based remote sensors over a variety of surface and meteorological conditions. Second, planned observational campaigns (the Measurements of Aerosols Radiation and Clouds over the Southern Oceans MARCUS and the Southern Oceans Cloud Radiation Transport Experimental Study SOCRATES) should provide cloud, aerosol, radiative and precipitation observations over the pristine and continually cloudy Southern Oceans that are remote from natural and continental anthropogenic aerosol sources should provide a process-oriented understanding of cloud-aerosol interactions in liquid and ice clouds.

Are Caribbean reef sharks, Carcharhinus perezi, able to perceive human body orientation?

PubMed

Ritter, Erich K; Amin, Raid

2014-05-01

The present study examines the potential capability of Caribbean reef sharks to perceive human body orientation, as well as discussing the sharks' swimming patterns in a person's vicinity. A standardized video method was used to record the scenario of single SCUBA divers kneeling in the sand and the approach patterns of sharks, combined with a control group of two divers kneeling back-to-back. When approaching a single test-subject, significantly more sharks preferred to swim outside the person's field of vision. The results suggest that these sharks are able to identify human body orientation, but the mechanisms used and factors affecting nearest distance of approach remain unclear.

Simplified Models of Vector Control Impact upon Malaria Transmission by Zoophagic Mosquitoes

PubMed Central

Kiware, Samson S.; Chitnis, Nakul; Moore, Sarah J.; Devine, Gregor J.; Majambere, Silas; Merrill, Stephen; Killeen, Gerry F.

2012-01-01

Background High coverage of personal protection measures that kill mosquitoes dramatically reduce malaria transmission where vector populations depend upon human blood. However, most primary malaria vectors outside of sub-Saharan Africa can be classified as “very zoophagic,” meaning they feed occasionally (<10% of blood meals) upon humans, so personal protection interventions have negligible impact upon their survival. Methods and Findings We extended a published malaria transmission model to examine the relationship between transmission, control, and the baseline proportion of bloodmeals obtained from humans (human blood index). The lower limit of the human blood index enables derivation of simplified models for zoophagic vectors that (1) Rely on only three field-measurable parameters. (2) Predict immediate and delayed (with and without assuming reduced human infectivity, respectively) impacts of personal protection measures upon transmission. (3) Illustrate how appreciable indirect communal-level protection for non-users can be accrued through direct personal protection of users. (4) Suggest the coverage and efficacy thresholds required to attain epidemiological impact. The findings suggest that immediate, indirect, community-wide protection of users and non-users alike may linearly relate to the efficacy of a user’s direct personal protection, regardless of whether that is achieved by killing or repelling mosquitoes. High protective coverage and efficacy (≥80%) are important to achieve epidemiologically meaningful impact. Non-users are indirectly protected because the two most common species of human malaria are strict anthroponoses. Therefore, the small proportion of mosquitoes that are killed or diverted while attacking humans can represent a large proportion of those actually transmitting malaria. Conclusions Simplified models of malaria transmission by very zoophagic vectors may be used by control practitioners to predict intervention impact interventions using three field-measurable parameters; the proportion of human exposure to mosquitoes occurring when an intervention can be practically used, its protective efficacy when used, and the proportion of people using it. PMID:22701527

Magnetically Actuated Propellant Orientation, Controlling Fluids in a Low-Gravity Environment

NASA Technical Reports Server (NTRS)

Martin, James J.; Holt, James B.

2000-01-01

Cryogenic fluid management (CFM) is a technology area common to virtually every space transportation propulsion concept envisioned. Storage, supply, transfer and handling of sub-critical cryogenic fluids are basic capabilities that have long been needed by multiple programs and the need is expected to continue in the future. The use of magnetic fields provides another method, which could replace or augment current/traditional approaches, potentially simplifying vehicle operational constraints. The magnetically actuated propellant orientation (MAPO) program effort focused on the use of magnetic fields to control fluid motion as it relates to positioning (i.e. orientation and acquisition) of a paramagnetic substance such as LO2. Current CFM state- of-the-art systems used to control and acquire propellant in low gravity environments rely on liquid surface tension devices which employ vanes, fine screen mesh channels and baskets. These devices trap and direct propellant to areas where it's needed and have been used routinely with storable (non-cryogenic) propellants. However, almost no data exists r,egarding their operation in cryogenics and the use of such devices confronts designers with a multitude of significant technology issues. Typical problems include a sensitivity to screen dry out (due to thermal loads and pressurant gas) and momentary adverse accelerations (generated from either internal or external sources). Any of these problems can potentially cause the acquisition systems to ingest or develop vapor and fail. The use of lightweight high field strength magnets may offer a valuable means of augmenting traditional systems potentially mitigating or at least easing operational requirements. Two potential uses of magnetic fields include: 1) strategically positioning magnets to keep vent ports clear of liquid (enabling low G vented fill operations), and 2) placing magnets in the center or around the walls of the tank to create an insulating vapor pocket (between the liquid and the tank wall) which could effectively lower heat transfer to the liquid (enabling increased storage time).

78 FR 39352 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing of Proposed Rule Change Relating...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-01

... provide that, so long as ICE Group directly or indirectly controls any U.S. Regulated Subsidiary, the... indirectly controls any U.S. Regulated Subsidiary, the books, records and premises of ICE Group will be... Group directly or indirectly controls any Regulated Subsidiary (as defined in the NYSE Group Certificate...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 3 2012-01-01 2012-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

Full-Scale Field Test of Wake Steering

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

Fleming, Paul; Annoni, Jennifer; Scholbrock, Andrew

Wind farm control, in which turbine controllers are coordinated to improve farmwide performance, is an active field of research. One form of wind farm control is wake steering, in which a turbine is yawed to the inflow to redirect its wake away from downstream turbines. Wake steering has been studied in depth in simulations as well as in wind tunnels and scaled test facilities. This work performs a field test of wake steering on a full-scale turbine. In the campaign, the yaw controller of the turbine has been set to track different yaw misalignment set points while a nacelle-mounted lidarmore » scans the wake at several ranges downwind. The lidar measurements are combined with turbine data, as well as measurements of the inflow made by a highly instrumented meteorological mast. In conclusion, these measurements are then compared to the predictions of a wind farm control-oriented model of wakes.« less

Full-Scale Field Test of Wake Steering

DOE PAGES

Fleming, Paul; Annoni, Jennifer; Scholbrock, Andrew; ...

2017-06-13

Wind farm control, in which turbine controllers are coordinated to improve farmwide performance, is an active field of research. One form of wind farm control is wake steering, in which a turbine is yawed to the inflow to redirect its wake away from downstream turbines. Wake steering has been studied in depth in simulations as well as in wind tunnels and scaled test facilities. This work performs a field test of wake steering on a full-scale turbine. In the campaign, the yaw controller of the turbine has been set to track different yaw misalignment set points while a nacelle-mounted lidarmore » scans the wake at several ranges downwind. The lidar measurements are combined with turbine data, as well as measurements of the inflow made by a highly instrumented meteorological mast. In conclusion, these measurements are then compared to the predictions of a wind farm control-oriented model of wakes.« less

Multimode marine engine room simulation system based on field bus technology

NASA Astrophysics Data System (ADS)

Zheng, Huayao; Deng, Linlin; Guo, Yi

2003-09-01

Developing multi mode MER (Marine Engine Room) Labs is the main work in Marine Simulation Center, which is the key lab of Communication Ministry of China. It includes FPP (Fixed Pitch Propeller) and CPP (Controllable Pitch Propeller) mode MER simulation systems, integrated electrical propulsion mode MER simulation system, physical mode MER lab, etc. FPP mode simulation system, which was oriented to large container ship, had been completed since 1999, and got second level of Shanghai Municipal Science and Technical Progress award. This paper mainly introduces the recent development and achievements of Marine Simulation Center. Based on the Lon Works field bus, the structure characteristics and control strategies of completely distributed intelligent control network are discussed. The experiment mode of multi-nodes field bus detection and control system is described. Besides, intelligent fault diagnosis technology about some mechatronics integration control systems explored is also involved.

Impact of self-orientations and work-context-related variables on the well-being of public- and private-sector Turkish employees.

PubMed

Imamoğlu, E Olcay; Beydoğan, Başak

2011-01-01

The authors (a) explored the impact of individual differences in self-orientations (i.e., relatedness and individuation) of 383 Turkish public- and private-sector employees on their basic need satisfaction at work and their well-being (i.e., life satisfaction and psychological well-being); (b) considered differences in perceived autonomy- and relatedness-supportiveness of the work contexts; and (c) tested a model in which the relationship between self-orientations and well-being is partially mediated by the perceived supportiveness of the work context and the need satisfaction of employees at work, using structural equation modeling. Results suggest that self-orientations of employees predict their well-being both directly and indirectly through the mediation of perceived supportiveness and need satisfaction provided by the work context, which seem to vary according to sector type.

Fast optical switch having reduced light loss

NASA Technical Reports Server (NTRS)

Nelson, Bruce N. (Inventor); Cooper, Ronald F. (Inventor)

1992-01-01

An electrically controlled optical switch uses an electro-optic crystal of the type having at least one set of fast and slow optical axes. The crystal exhibits electric field induced birefringence such that a plane of polarization oriented along a first direction of a light beam passing through the crystal may be switched to a plane of polarization oriented along a second direction. A beam splitting polarizer means is disposed at one end of the crystal and directs a light beam passing through the crystal whose plane of polarization is oriented along the first direction differently from a light beam having a plane of polarization oriented along the second direction. The electro-optic crystal may be chosen from the crystal classes 43m, 42m, and 23. In a preferred embodiment, the electro-optic crystal is a bismuth germanium oxide crystal or a bismuth silicon oxide crystal. In another embodiment of the invention, polarization control optics are provided which transmit substantially all of the incident light to the electro-optic crystal, substantially reducing the insertion loss of the switch.

Directional orientation of birds by the magnetic field under different light conditions

PubMed Central

Wiltschko, Roswitha; Stapput, Katrin; Thalau, Peter; Wiltschko, Wolfgang

2010-01-01

This paper reviews the directional orientation of birds with the help of the geomagnetic field under various light conditions. Two fundamentally different types of response can be distinguished. (i) Compass orientation controlled by the inclination compass that allows birds to locate courses of different origin. This is restricted to a narrow functional window around the total intensity of the local geomagnetic field and requires light from the short-wavelength part of the spectrum. The compass is based on radical-pair processes in the right eye; magnetite-based receptors in the beak are not involved. Compass orientation is observed under ‘white’ and low-level monochromatic light from ultraviolet (UV) to about 565 nm green light. (ii) ‘Fixed direction’ responses occur under artificial light conditions such as more intense monochromatic light, when 590 nm yellow light is added to short-wavelength light, and in total darkness. The manifestation of these responses depends on the ambient light regime and is ‘fixed’ in the sense of not showing the normal change between spring and autumn; their biological significance is unclear. In contrast to compass orientation, fixed-direction responses are polar magnetic responses and occur within a wide range of magnetic intensities. They are disrupted by local anaesthesia of the upper beak, which indicates that the respective magnetic information is mediated by iron-based receptors located there. The influence of light conditions on the two types of response suggests complex interactions between magnetoreceptors in the right eye, those in the upper beak and the visual system. PMID:19864263

The perception of three-dimensionality across continuous surfaces

NASA Technical Reports Server (NTRS)

Stevens, Kent A.

1989-01-01

The apparent three-dimensionality of a viewed surface presumably corresponds to several internal preceptual quantities, such as surface curvature, local surface orientation, and depth. These quantities are mathematically related for points within the silhouette bounds of a smooth, continuous surface. For instance, surface curvature is related to the rate of change of local surface orientation, and surface orientation is related to the local gradient of distance. It is not clear to what extent these 3D quantities are determined directly from image information rather than indirectly from mathematically related forms, by differentiation or by integration within boundary constraints. An open empirical question, for example, is to what extent surface curvature is perceived directly, and to what extent it is quantitative rather than qualitative. In addition to surface orientation and curvature, one derives an impression of depth, i.e., variations in apparent egocentric distance. A static orthographic image is essentially devoid of depth information, and any quantitative depth impression must be inferred from surface orientation and other sources. Such conversion of orientation to depth does appear to occur, and even to prevail over stereoscopic depth information under some circumstances.

Toxicity of emamectin benzoate to Cydia pomonella (L.) and Cydia molesta (Busck) (Lepidoptera: Tortricidae): laboratory and field tests.

PubMed

Ioriatti, Claudio; Anfora, Gianfranco; Angeli, Gino; Civolani, Stefano; Schmidt, Silvia; Pasqualini, Edison

2009-03-01

Emamectin benzoate is a novel macrocyclic lactone insecticide derived from naturally occurring avermectin molecules isolated by fermentation from the soil microorganism Streptomyces avermitilis Kim & Goodfellow. The present study aims to evaluate the toxicity of emamectin benzoate to codling moth, Cydia pomonella (L.), and oriental fruit moth, C. molesta (Busck), under laboratory and semi-field conditions. Dose response bioassays showed that emamectin benzoate had a high level of intrinsic toxicity to early-stage larvae of both species, and that contact activity might contribute significantly to mortality. In the semi-field trials, residual toxicity lasted for more than 1 week. Ovicidal activity was recorded only for C. pomonella (approximately 30%), irrespective of the concentrations tested. Field trials confirmed the efficacy of emamectin benzoate on codling moth when applied at 7 day intervals. Fruit damage, both from the first and second generations, was comparable with that on treatment with chlorpyrifos-ethyl, used as a chemical reference. Emamectin benzoate may be considered a valuable tool for the control of codling moth as a component of an IPM programme. Its collective advantages are: high efficacy, lack of cross-resistance with currently used products, control of secondary pests such as oriental fruit moth and selective toxicity that spares beneficials. 2008 Society of Chemical Industry

Reliable low-power control of ultrafast vortex-core switching with the selectivity in an array of vortex states by in-plane circular-rotational magnetic fields and spin-polarized currents

NASA Astrophysics Data System (ADS)

Kim, Sang-Koog; Lee, Ki-Suk; Yu, Young-Sang; Choi, Youn-Seok

2008-01-01

The authors investigated the technological utility of counterclockwise (CCW) and clockwise (CW) circular-rotating fields (HCCW and HCW) and spin-polarized currents with an angular frequency ωH close to the vortex eigenfrequency ωD, for the reliable, low-power, and selective switching of the bistate magnetization (M) orientations of a vortex core (VC) in an array of soft magnetic nanoelements. CCW and CW circular gyrotropic motions in response to HCCW and HCW, respectively, show remarkably contrasting resonant behaviors, (i.e., extremely large-amplitude resonance versus small-amplitude nonresonance), depending on the M orientation of a given VC. Owing to this asymmetric resonance characteristics, the HCCW(HCW) with ωH˜ωD can be used to effectively switch only the up (down) core to its downward (upward) M orientation, selectively, by sufficiently low field (˜10Oe) and current density (˜107A/cm2). This work provides a reliable, low power, effective means of information storage, information recording, and information readout in vortex-based random access memory, simply called VRAM.

Haze, clouds and limited sky visibility: polarotactic orientation of crickets under difficult stimulus conditions.

PubMed

Henze, Miriam J; Labhart, Thomas

2007-09-01

Field crickets (Gryllus campestris L.) are able to detect the orientation of the electric vector (e-vector) of linearly polarized light. They presumably use this sense to exploit the celestial polarization pattern for course control or navigation. Polarization vision in crickets can be tested by eliciting a spontaneous polarotactic response. Previously, wide and 100% polarized stimuli were employed to induce this behavior. However, field crickets live on meadows where the observation of the sky is strongly limited by surrounding vegetation. Moreover, degrees of polarization (d) in the natural sky are much lower than 100%. We have therefore investigated thresholds for the behavioral response to polarized light under conditions mimicking those experienced by the insects in the field. We show that crickets are able to rely on polarized stimuli of just 1 degrees diameter. We also provide evidence that they exploit polarization down to an (average) polarization level of less than 7%, irrespective of whether the stimulus is homogeneous, such as under haze, or patched, such as a sky spotted by clouds. Our data demonstrate that crickets can rely on skylight polarization even under unfavorable celestial conditions, emphasizing the significance of polarized skylight orientation for insects.

Are gay men and lesbians discriminated against when applying for jobs? A four-city, Internet-based field experiment.

PubMed

Bailey, John; Wallace, Michael; Wright, Bradley

2013-01-01

An Internet-based field experiment was conducted to examine potential hiring discrimination based on sexual orientation; specifically, the "first contact" between job applicants and employers was looked at. In response to Internet job postings on CareerBuilder.com®, more than 4,600 resumes were sent to employers in 4 U.S. cities: Philadelphia, Chicago, Dallas, and San Francisco. The resumes varied randomly with regard to gender, implied sexual orientation, and other characteristics. Two hypotheses were tested: first, that employers' response rates vary by the applicants' assumed sexuality; and second, that employers' Response Rates by Sexuality vary by city. Effects of city were controlled for to hold constant any variation in labor market conditions in the 4 cities. Based on employer responses to the applications, it was concluded that there is no evidence that gay men or lesbians are discriminated against in their first encounter with employers, and no significant variation across cities in these encounters was found. Implications of these results for the literature on hiring discrimination based on sexual orientation, the strengths and limitations of the research, and the potential for the Internet-based field experiment design in future studies of discrimination are discussed.

Indirect effects of bioinsecticides on the nontarget fauna: The Camargue experiment calls for future research

NASA Astrophysics Data System (ADS)

Poulin, Brigitte

2012-10-01

Following its high selectivity and low toxicity to nontarget organisms, Bacillus thuringiensis var. israelensis (Bti) has become the most commonly used microbial agent to control mosquitoes worldwide. Considered non-toxic to mammals, birds, fish, plants and most aquatic organisms, Bti direct effects on the nontarget fauna are largely limited to non-biting midges (Chironomidae). Studies addressing the indirect effects of Bti through food web perturbations are scanty and showed no significant results. Mosquito-control in southern France was implemented in 1965 using various insecticides over 400 km of coast. In spite of a high mosquito nuisance, the Camargue wetlands were excluded from this control programme to preserve biodiversity. The expanding use of Bti has prompted the implementation of an experimental mosquito control in 2006 involving 2500 of the 25,000 ha of larval biotopes of the Camargue, accompanied by impact studies on the nontarget fauna. Using birds from natural and human-inhabited areas as model species, we assessed trophic perturbations caused by three years of Bti applications. The preliminary results of this 5-yr programme revealed significant effects of Bti spraying on abundance of reed-dwelling invertebrates serving as food to passerines, as well as on the diet and breeding success of house martins nesting in rural estates and small towns. Very few studies (if any) have provided such compelling evidence of an insecticide affecting vertebrate populations, putting into question the environmental-friendly character of Bti, at least in some areas. The significance of these results are discussed within a wider context and completed with an analysis of the current Bti bibliography to highlight and orient priorities for future research on this topic.

Separating Direct and Indirect Turbofan Engine Combustion Noise While Estimating Post-Combustion (Post-Flame) Residence Time Using the Correlation Function

NASA Technical Reports Server (NTRS)

Miles, Jeffrey Hilton

2011-01-01

A previous investigation on the presence of direct and indirect combustion noise for a full-scale turbofan engine using a far-field microphone at 130 is extended by also examining signals obtained at two additional downstream directions using far-field microphones at 110 deg and 160 deg. A generalized cross-correlation function technique is used to study the change in propagation time to the far field of the combined direct and indirect combustion noise signal as a sequence of low-pass filters are applied. The filtering procedure used produces no phase distortion. As the low-pass filter frequency is decreased, the travel time increases because the relative amount of direct combustion noise is reduced. The indirect combustion noise signal travels more slowly because in the combustor entropy fluctuations move with the flow velocity, which is slow compared to the local speed of sound. The indirect combustion noise signal travels at acoustic velocities after reaching the turbine and being converted into an acoustic signal. The direct combustion noise is always propagating at acoustic velocities. The results show that the estimated indirect combustion noise time delay values (post-combustion residence times) measured at each angle are fairly consistent with one another for a relevant range of operating conditions and demonstrate source separation of a mixture of direct and indirect combustion noise. The results may lead to a better idea about the acoustics in the combustor and may help develop and validate improved reduced-order physics-based methods for predicting turbofan engine core noise.

Open and closed loop manipulation of charged microchiplets in an electric field

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

Lu, J. P., E-mail: jplu@parc.com; Thompson, J. D.; Whiting, G. L.

We demonstrate the ability to orient, position, and transport microchips (“chiplets”) with electric fields. In an open-loop approach, modified four phase traveling wave potential patterns manipulate chiplets in a dielectric solution using dynamic template agitation techniques. Repeatable parallel assembly of chiplets is demonstrated to a positional accuracy of 6.5 μm using electrodes of 200 μm pitch. Chiplets with dipole surface charge patterns are used to show that orientation can be controlled by adding unique charge patterns on the chiplets. Chip path routing is also demonstrated. With a closed-loop control system approach using video feedback, dielectric, and electrophoretic forces are used to achievemore » positioning accuracy of better than 1 μm with 1 mm pitch driving electrodes. These chip assembly techniques have the potential to enable future printer systems where inputs are electronic chiplets and the output is a functional electronic system.« less

Boundary Layer Flow Control by an Array of Ramp-Shaped Vortex Generators

NASA Technical Reports Server (NTRS)

Zaman, K. B. M. Q.; Hirt, S. M.; Bencic, T. J.

2012-01-01

Flow field survey results for the effect of ramp-shaped vortex generators (VG) on a turbulent boundary layer are presented. The experiments are carried out in a low-speed wind tunnel and the data are acquired primarily by hot-wire anemometry. Distributions of mean velocity and turbulent stresses as well as streamwise vorticity, on cross-sectional planes at various downstream locations, are obtained. These detailed flow field properties, including the boundary layer characteristics, are documented with the primary objective of aiding possible computational investigations. The results show that VG orientation with apex upstream, that produces a downwash directly behind it, yields a stronger pair of streamwise vortices. This is in contrast to the case with apex downstream that produces a pair of vortices of opposite sense. Thus, an array of VG s with the former orientation, usually considered for film-cooling application, may also be superior for mixing enhancement and boundary layer separation control. (See CASI ID 20120009374 for Supplemental CD-ROM.)

Boundary Layer Flow Control by an Array of Ramp-Shaped Vortex Generators

NASA Technical Reports Server (NTRS)

Zaman, K. B. M. Q.; Hirt, S. M.; Bencic, T. J.

2012-01-01

Flow field survey results for the effect of ramp-shaped vortex generators (VG) on a turbulent boundary layer are presented. The experiments are carried out in a low-speed wind tunnel and the data are acquired primarily by hot-wire anemometry. Distributions of mean velocity and turbulent stresses as well as streamwise vorticity, on cross-sectional planes at various downstream locations, are obtained. These detailed flow field properties, including the boundary layer characteristics, are documented with the primary objective of aiding possible computational investigations. The results show that VG orientation with apex upstream, that produces a downwash directly behind it, yields a stronger pair of streamwise vortices. This is in contrast to the case with apex downstream that produces a pair of vortices of opposite sense. Thus, an array of VG s with the former orientation, usually considered for film-cooling application, may also be superior for mixing enhancement and boundary layer separation control. The data files can be found on a supplemental CD.

Non-Markovianity in the optimal control of an open quantum system described by hierarchical equations of motion

NASA Astrophysics Data System (ADS)

Mangaud, E.; Puthumpally-Joseph, R.; Sugny, D.; Meier, C.; Atabek, O.; Desouter-Lecomte, M.

2018-04-01

Optimal control theory is implemented with fully converged hierarchical equations of motion (HEOM) describing the time evolution of an open system density matrix strongly coupled to the bath in a spin-boson model. The populations of the two-level sub-system are taken as control objectives; namely, their revivals or exchange when switching off the field. We, in parallel, analyze how the optimal electric field consequently modifies the information back flow from the environment through different non-Markovian witnesses. Although the control field has a dipole interaction with the central sub-system only, its indirect influence on the bath collective mode dynamics is probed through HEOM auxiliary matrices, revealing a strong correlation between control and dissipation during a non-Markovian process. A heterojunction is taken as an illustrative example for modeling in a realistic way the two-level sub-system parameters and its spectral density function leading to a non-perturbative strong coupling regime with the bath. Although, due to strong system-bath couplings, control performances remain rather modest, the most important result is a noticeable increase of the non-Markovian bath response induced by the optimally driven processes.

Orientation and spread of reconnection x-line in asymmetric current sheets

NASA Astrophysics Data System (ADS)

Liu, Y. H.; Hesse, M.; Wendel, D. E.; Kuznetsova, M.; Wang, S.

2017-12-01

The magnetic field in solar wind plasmas can shear with Earth's dipole magnetic field at arbitrary angles, and the plasma conditions on the two sides of the (magnetopause) current sheet can greatly differ. One of the outstanding questions in such asymmetric geometry is what local physics controls the orientation of the reconnection x-line; while the x-line in a simplified 2D model (simulation) always points out of the simulation plane by design, it is unclear how to predict the orientation of the x-line in a fully three-dimensional (3D) system. Using kinetic simulations run on Blue Waters, we develop an approach to explore this 3D nature of the reconnection x-line, and test hypotheses including maximizing the reconnection rate, tearing mode growth rate or reconnection outflow speed, and the bisection solution. Practically, this orientation should correspond to the M-direction of the local LMN coordinate system that is often employed to analyze diffusion region crossings by the Magnetospheric Multiscale Mission (MMS). In this talk, we will also discuss how an x-line spread from a point source in asymmetric geometries, and the boundary effect on the development of the reconnection x-line and turbulence.

Online low-field NMR spectroscopy for process control of an industrial lithiation reaction-automated data analysis.

PubMed

Kern, Simon; Meyer, Klas; Guhl, Svetlana; Gräßer, Patrick; Paul, Andrea; King, Rudibert; Maiwald, Michael

2018-05-01

Monitoring specific chemical properties is the key to chemical process control. Today, mainly optical online methods are applied, which require time- and cost-intensive calibration effort. NMR spectroscopy, with its advantage being a direct comparison method without need for calibration, has a high potential for enabling closed-loop process control while exhibiting short set-up times. Compact NMR instruments make NMR spectroscopy accessible in industrial and rough environments for process monitoring and advanced process control strategies. We present a fully automated data analysis approach which is completely based on physically motivated spectral models as first principles information (indirect hard modeling-IHM) and applied it to a given pharmaceutical lithiation reaction in the framework of the European Union's Horizon 2020 project CONSENS. Online low-field NMR (LF NMR) data was analyzed by IHM with low calibration effort, compared to a multivariate PLS-R (partial least squares regression) approach, and both validated using online high-field NMR (HF NMR) spectroscopy. Graphical abstract NMR sensor module for monitoring of the aromatic coupling of 1-fluoro-2-nitrobenzene (FNB) with aniline to 2-nitrodiphenylamine (NDPA) using lithium-bis(trimethylsilyl) amide (Li-HMDS) in continuous operation. Online 43.5 MHz low-field NMR (LF) was compared to 500 MHz high-field NMR spectroscopy (HF) as reference method.

Mothers’ Power Assertion, Children’s Negative, Adversarial Orientation, and Future Behavior Problems in Low-Income Families: Early Maternal Responsiveness as a Moderator of the Developmental Cascade

PubMed Central

Kim, Sanghag; Kochanska, Grazyna

2014-01-01

Parental power assertion, a key dimension of family environment, generally sets in motion detrimental developmental cascades; however, evidence suggests that other qualities of parenting, such as responsiveness, can significantly moderate those processes. Mechanisms that account for such moderating effects are not fully understood. We propose a conceptual model of processes linking parental power assertion, parental responsiveness, children’s negative, adversarial, rejecting orientation toward the parent, and behavior problems. We test that model in a short-term longitudinal design involving 186 low-income, ethnically diverse mothers and their toddlers. When children were 30 months, the dyads were observed in multiple, lengthy, naturalistic laboratory interactions to assess behaviorally mothers’ responsiveness and their power-assertive control style. At 33 months, we observed behavioral indicators of children’s negative, adversarial, rejecting orientation toward the mothers in several naturalistic and standardized paradigms. At 40 months, mothers rated children’s behavior problems. The proposed moderated mediation sequence, tested using a new approach, PROCESS (Hayes, 2013), was supported. The indirect effect from maternal power assertion to children’s negative, adversarial orientation to future behavior problems was present when mothers’ responsiveness was either low or average but absent when mothers were highly responsive. This study elucidates a potential process that may link parental power assertion with behavior problems and highlights how positive aspects of parenting can moderate this process and defuse maladaptive developmental cascades. It also suggests possible targets for parenting intervention and prevention efforts. PMID:25401483

Mothers' power assertion; children's negative, adversarial orientation; and future behavior problems in low-income families: early maternal responsiveness as a moderator of the developmental cascade.

PubMed

Kim, Sanghag; Kochanska, Grazyna

2015-02-01

Parental power assertion, a key dimension of family environment, generally sets in motion detrimental developmental cascades; however, evidence suggests that other qualities of parenting, such as responsiveness, can significantly moderate those processes. Mechanisms that account for such moderating effects are not fully understood. We propose a conceptual model of processes linking parental power assertion, parental responsiveness, children's negative, adversarial, rejecting orientation toward the parent, and behavior problems. We test that model in a short-term longitudinal design involving 186 low-income, ethnically diverse mothers and their toddlers. When children were 30 months, the dyads were observed in multiple, lengthy, naturalistic laboratory interactions to assess behaviorally mothers' responsiveness and their power-assertive control style. At 33 months, we observed behavioral indicators of children's negative, adversarial, rejecting orientation toward the mothers in several naturalistic and standardized paradigms. At 40 months, mothers rated children's behavior problems. The proposed moderated mediation sequence, tested using a new approach, PROCESS (Hayes, 2013), was supported. The indirect effect from maternal power assertion to children's negative, adversarial orientation to future behavior problems was present when mothers' responsiveness was either low or average but absent when mothers were highly responsive. This study elucidates a potential process that may link parental power assertion with behavior problems and highlights how positive aspects of parenting can moderate this process and defuse maladaptive developmental cascades. It also suggests possible targets for parenting intervention and prevention efforts. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Effects of external stress field on the charge stability of nitrogen vacancy centers in diamond

NASA Astrophysics Data System (ADS)

Yao, Miao-Miao; Zhu, Tian-Yuan; Shu, Da-Jun

2017-07-01

The interaction of the atom-like defects in semiconductors with external fields provides an avenue to quantum information processing and nanoscale sensors. Meanwhile, external fields may induce instability of the desired charge state of the defects. It is essential to understand how the charge state of a defect is affected by external fields that introduced in diverse applications. In this letter, we explore the stability of the negatively charged state (NV-) and the neutral state (NV0) of the nitrogen vacancy (NV) center in diamond under stress by first-principles calculations. We find that the relative stability of NV- to NV0 is always reduced by the stress if the NV center is free to relax its orientation. Once the NV center has formed and retains its orientation, however, the relative stability of NV- can be always enhanced by compressive stress along its trigonal symmetry axis. We believe that the results are not only significant for control of the charge stability of NV center but also enlightening for applications based on specific charge states of other kinds of defects in the stress field.

Electric Field Generation and Control of Bipartite Quantum Entanglement between Electronic Spins in Mixed Valence Polyoxovanadate [GeV14O40]8.

PubMed

Palii, Andrew; Aldoshin, Sergey; Tsukerblat, Boris; Borràs-Almenar, Juan José; Clemente-Juan, Juan Modesto; Cardona-Serra, Salvador; Coronado, Eugenio

2017-08-21

As part of the search for systems in which control of quantum entanglement can be achieved, here we consider the paramagnetic mixed valence polyoxometalate K 2 Na 6 [GeV 14 O 40 ]·10H 2 O in which two electrons are delocalized over the 14 vanadium ions. Applying a homogeneous electric field can induce an antiferromagnetic coupling between the two delocalized electronic spins that behave independently in the absence of the field. On the basis of the proposed theoretical model, we show that the external field can be used to generate controllable quantum entanglement between the two electronic spins traveling over a vanadium network of mixed valence polyoxoanion [GeV 14 O 40 ] 8- . Within a simplified two-level picture of the energy pattern of the electronic pair based on the previous ab initio analysis, we evaluate the temperature and field dependencies of concurrence and thus indicate that the entanglement can be controlled via the temperature, magnitude, and orientation of the electric field with respect to molecular axes of [GeV 14 O 40 ] 8- .

Control of electron spin and orbital resonances in quantum dots through spin-orbit interactions

NASA Astrophysics Data System (ADS)

Stano, Peter; Fabian, Jaroslav

2008-01-01

The influence of a resonant oscillating electromagnetic field on a single electron in coupled lateral quantum dots in the presence of phonon-induced relaxation and decoherence is investigated. Using symmetry arguments, it is shown that the spin and orbital resonances can be efficiently controlled by spin-orbit interactions. The control is possible due to the strong sensitivity of the Rabi frequency to the dot configuration (the orientation of the dot and the applied static magnetic field); the sensitivity is a result of the anisotropy of the spin-orbit interactions. The so-called easy passage configuration is shown to be particularly suitable for a magnetic manipulation of spin qubits, ensuring long spin relaxation times and protecting the spin qubits from electric field disturbances accompanying on-chip manipulations.

Three-dimensional control of crystal growth using magnetic fields

NASA Astrophysics Data System (ADS)

Dulikravich, George S.; Ahuja, Vineet; Lee, Seungsoo

1993-07-01

Two coupled systems of partial differential equations governing three-dimensional laminar viscous flow undergoing solidification or melting under the influence of arbitrarily oriented externally applied magnetic fields have been formulated. The model accounts for arbitrary temperature dependence of physical properties including latent heat release, effects of Joule heating, magnetic field forces, and mushy region existence. On the basis of this model a numerical algorithm has been developed and implemented using central differencing on a curvilinear boundary-conforming grid and Runge-Kutta explicit time-stepping. The numerical results clearly demonstrate possibilities for active and practically instantaneous control of melt/solid interface shape, the solidification/melting front propagation speed, and the amount and location of solid accrued.

ELF communications system ecological monitoring program: Pollinating insect studies

NASA Astrophysics Data System (ADS)

Strickler, Karen; Schriber, J. Mark

1994-11-01

High voltage transmission lines and the earth's and other magnetic fields have been shown to affect honeybee reproduction, survival, orientation, and nest structure. ELY EM fields could have similar effects on native megachilid bees. Two species in the genus Megachile were abundant in artificial nests at experimental and control areas in Dickinson and Iron Counties in Michigan. Data on their nest architecture, nest activity, and emergence/mortality were collected between 1983 and 1993. Eight hypotheses concerning the possible effects of ELY EM fields were considered using these data. The ELY antenna has been fully operational since the summer of 1989. Tests of the hypotheses compare control vs. experimental areas before and after the ELY antenna became fully operational.

Analysis of Control-Oriented Wake Modeling Tools Using Lidar Field Results

DOE PAGES

Annoni, Jennifer; Fleming, Paul; Scholbrock, Andrew; ...

2018-02-08

Wind turbines in a wind farm operate individually to maximize their own performance regardless of the impact of aerodynamic interactions on neighboring turbines. Wind farm controls can be used to increase power production or reduce overall structural loads by properly coordinating turbines. One wind farm control strategy that is addressed in literature is known as wake steering, wherein upstream turbines operate in yaw misaligned conditions to redirect their wakes away from downstream turbines. The National Renewable Energy Laboratory (NREL) in Golden, CO conducted a demonstration of wake steering on a single utility-scale turbine. In this study, the turbine was operatedmore » at various yaw misalignment setpoints while a lidar mounted on the nacelle scanned five downstream distances. The lidar measurements were combined with turbine data, as well as measurements of the inflow made by a highly instrumented meteorological mast upstream. The full-scale measurements are used to validate controls-oriented tools, including wind turbine wake models, used for wind farm controls and optimization. This paper presents a quantitative comparison of the lidar data and controls-oriented wake models under different atmospheric conditions and turbine operation. The results show good agreement between the lidar data and the models under these different conditions.« less

Analysis of Control-Oriented Wake Modeling Tools Using Lidar Field Results

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

Annoni, Jennifer; Fleming, Paul; Scholbrock, Andrew

Wind turbines in a wind farm operate individually to maximize their own performance regardless of the impact of aerodynamic interactions on neighboring turbines. Wind farm controls can be used to increase power production or reduce overall structural loads by properly coordinating turbines. One wind farm control strategy that is addressed in literature is known as wake steering, wherein upstream turbines operate in yaw misaligned conditions to redirect their wakes away from downstream turbines. The National Renewable Energy Laboratory (NREL) in Golden, CO conducted a demonstration of wake steering on a single utility-scale turbine. In this study, the turbine was operatedmore » at various yaw misalignment setpoints while a lidar mounted on the nacelle scanned five downstream distances. The lidar measurements were combined with turbine data, as well as measurements of the inflow made by a highly instrumented meteorological mast upstream. The full-scale measurements are used to validate controls-oriented tools, including wind turbine wake models, used for wind farm controls and optimization. This paper presents a quantitative comparison of the lidar data and controls-oriented wake models under different atmospheric conditions and turbine operation. The results show good agreement between the lidar data and the models under these different conditions.« less

Effects of coil orientation on the electric field induced by TMS over the hand motor area

NASA Astrophysics Data System (ADS)

Laakso, Ilkka; Hirata, Akimasa; Ugawa, Yoshikazu

2014-01-01

Responses elicited by transcranial magnetic stimulation (TMS) over the hand motor area depend on the position and orientation of the stimulating coil. In this work, we computationally investigate the induced electric field for multiple coil orientations and locations in order to determine which parts of the brain are affected and how the sensitivity of motor cortical activation depends on the direction of the electric field. The finite element method is used for calculating the electric field induced by TMS in two individual anatomical models of the head and brain. The orientation of the coil affects both the strength and depth of penetration of the electric field, and the field strongly depends on the direction of the sulcus, where the target neurons are located. The coil position that gives the strongest electric field in the target cortical region may deviate from the closest scalp location by a distance on the order of 1 cm. Together with previous experimental data, the results support the hypothesis that the cortex is most sensitive to fields oriented perpendicular to the cortical layers, while it is relatively insensitive to fields parallel to them. This has important implications for targeting of TMS. To determine the most effective coil position and orientation, it is essential to consider both biological (the direction of the targeted axons) and physical factors (the strength and direction of the electric field).

The effects of incidence angle on film dosimetry and their consequences in IMRT dose verification.

PubMed

Srivastava, R P; De Wagter, C

2012-10-01

The dosimetric accuracy of EDR2 radiographic film has been rigorously assessed in regular and intensity modulated beams for various incidence angles, including the parallel and perpendicular orientation. There clearly exists confusion in literature regarding the effect of film orientation. The primary aim is to clarify potential sources of the confusion and to gain physical insight into the film orientation effect with a link to radiochromic film as well. An inverse pyramid IMRT field, consisting of six regular and elongated 3 × 20 cm(2) field segments, was studied in perpendicular and parallel orientation. Assessment of film self-perturbation and intrinsic directional sensitivity were also included in the experiments. Finally, the authors investigated the orientational effect in composite beams in the two extreme orientations, i.e., perpendicular and parallel. The study of an inverse pyramid dose profile revealed good agreement between the perpendicular film and the diamond detector within 0.5% in the low-scatter regions for both 6 and 18 MV. The parallel oriented film demonstrated a 3% under-response at 5-cm (6 MV) depth against the perpendicular orientation, but both orientations over responded equally in the central region, which received only scattered dose, at both 5- and 20-cm depths. In a regular 6-MV 5 × 5 cm(2) field, a 4.1% lower film response was observed in the parallel orientation compared to perpendicular orientation. The under response gradually increased to 6% when reducing the field size to 0.5 × 5 cm(2). On the other hand, the film showed a 1.7% lower response in parallel orientation for the large field size of 20 × 20 cm(2) at 5-cm depth but the difference disappeared at 10 cm. At 18 MV, similar but somewhat lower differences were found between the two orientations. The directional sensitivity of the film diminishes with increasing field size and depth. Surprisingly a composite IMRT beam consisting of 20 adjacent strip segments also produced a significant orientational dependence of film response, notwithstanding the large total field size of 20 × 20 cm(2). This analysis allowed the development of a hypothesis about the physics behind the orientational dependence of film response in general and to formulate precautions when using film dosimetry in the dosimetric verification of multibeam treatments.

Mechanisms of anode power deposition in a low pressure free burning arc

NASA Technical Reports Server (NTRS)

Soulas, George C.; Myers, Roger M.

1994-01-01

Anode power deposition is a dominant power loss mechanism for arc jets and MPD thrusters. In this study, a free burning arc experiment was operated at pressures and current densities similar to those in arc jets and MPD thrusters in an attempt to identify the physics controlling this loss mechanism. Use of a free burning arc allowed for the isolation of independent variables controlling anode power deposition and provided a convenient and flexible way to cover a broad range of currents, anode surface pressures, and applied magnetic field strengths and orientations using an argon gas. Test results showed that anode power deposition decreased with increasing anode surface pressure up to 6.7 Pa (0.05 torr) and then became insensitive to pressure. Anode power increased with increasing arc current while the electron number density near the anode surface increased linearity. Anode power also increased with increasing applied magnetic field strength due to an increasing anode fall voltage. Applied magnetic field orientation had an effect only at high currents and low anode surface pressures, where anode power decreased when applied field lines intercepted the anode surface. The results demonstrated that anode power deposition was dominated by the current carrying electrons and that the anode fall voltage was the largest contributor. Furthermore, the results showed that anode power deposition can be reduced by operating at increased anode pressures, reduced arc currents, and applied magnetic field strengths and with magnetic field lines intercepting the anode.

Evaluating the Impact of Collectivism and Individualism on Argumentative Writing by Chinese and North American College Students.

ERIC Educational Resources Information Center

Wu, Su-Yueh; Rubin, Donald L.

2000-01-01

Analyzes writing features conceptually linked to collectivist or individualist orientations among students from Taiwan and the United States. Notes that theses features were indirectness, personal disclosure, use of proverbs and other canonical expressions, collective self, and assertiveness. Makes comparisons across languages and nationalities…

An Investigation of the Association between Teacher-Student Relations and School Adjustment Competencies in Turkey

ERIC Educational Resources Information Center

Koca, Fatih

2017-01-01

In this study, the researcher examined the direct and indirect effects of student-teacher relationship, students' social skills, and behavioral orientation on students' academic competency in Turkish first-grade educational settings. For most Turkish children, the entry into first grade is their first formal schooling experience. Understanding how…

Tensile-strain effect of inducing the indirect-to-direct band-gap transition and reducing the band-gap energy of Ge

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

Inaoka, Takeshi, E-mail: inaoka@phys.u-ryukyu.ac.jp; Furukawa, Takuro; Toma, Ryo

By means of a hybrid density-functional method, we investigate the tensile-strain effect of inducing the indirect-to-direct band-gap transition and reducing the band-gap energy of Ge. We consider [001], [111], and [110] uniaxial tensility and (001), (111), and (110) biaxial tensility. Under the condition of no normal stress, we determine both normal compression and internal strain, namely, relative displacement of two atoms in the primitive unit cell, by minimizing the total energy. We identify those strain types which can induce the band-gap transition, and evaluate the critical strain coefficient where the gap transition occurs. Either normal compression or internal strain operatesmore » unfavorably to induce the gap transition, which raises the critical strain coefficient or even blocks the transition. We also examine how each type of tensile strain decreases the band-gap energy, depending on its orientation. Our analysis clearly shows that synergistic operation of strain orientation and band anisotropy has a great influence on the gap transition and the gap energy.« less

Nonlinear control of high-frequency phonons in spider silk

NASA Astrophysics Data System (ADS)

Schneider, Dirk; Gomopoulos, Nikolaos; Koh, Cheong Y.; Papadopoulos, Periklis; Kremer, Friedrich; Thomas, Edwin L.; Fytas, George

2016-10-01

Spider dragline silk possesses superior mechanical properties compared with synthetic polymers with similar chemical structure due to its hierarchical structure comprised of partially crystalline oriented nanofibrils. To date, silk’s dynamic mechanical properties have been largely unexplored. Here we report an indirect hypersonic phononic bandgap and an anomalous dispersion of the acoustic-like branch from inelastic (Brillouin) light scattering experiments under varying applied elastic strains. We show the mechanical nonlinearity of the silk structure generates a unique region of negative group velocity, that together with the global (mechanical) anisotropy provides novel symmetry conditions for gap formation. The phononic bandgap and dispersion show strong nonlinear strain-dependent behaviour. Exploiting material nonlinearity along with tailored structural anisotropy could be a new design paradigm to access new types of dynamic behaviour.

Electrical control of optical orientation of neutral and negatively charged excitons in an n -type semiconductor quantum well

NASA Astrophysics Data System (ADS)

Dzhioev, R. I.; Korenev, V. L.; Lazarev, M. V.; Sapega, V. F.; Gammon, D.; Bracker, A. S.

2007-01-01

We report electric field induced increase of spin orientation of negatively charged excitons (trions) localized in n -type GaAs/AlGaAs quantum well. Under resonant excitation of free neutral heavy-hole excitons, the polarization of trions increases dramatically with electrical injection of electrons. The polarization enhancement correlates strongly with trion/exciton luminescence intensity ratio. This effect results from a very efficient trapping of free neutral excitons by the quantum well interfacial fluctuations (“natural” quantum dots) containing resident electrons.

Role divergence and complexity in gerontological home care.

PubMed

Kaye, L W

1989-01-01

This study documents high levels of role complexity and functional overlap in the field of home health care. Personnel perform a wide range of "professional/organizational" and "community/familial" service functions though the emphasis is on the delivery of a battery of pseudo family-like tasks. The importance of a familial orientation does not significantly decline when controlling for length of employment or organizational rationality. Role orientation is, however, significantly associated with a worker's chronological age. Results lead to program planning recommendations meant to influence staff training paradigms in home health care.

Retinal constraints on orientation specificity in cat visual cortex.

PubMed

Schall, J D; Vitek, D J; Leventhal, A G

1986-03-01

Most retinal ganglion cells (Levick and Thibos, 1982) and cortical cells (Leventhal, 1983; Leventhal et al., 1984) subserving peripheral vision respond best to stimuli that are oriented radially, i.e., like the spokes of a wheel with the area centralis at the hub. We have extended this work by comparing directly the distributions of orientations represented in topographically corresponding regions of retina and visual cortex. Both central and peripheral regions were studied. The relations between the orientations of neighboring ganglion cells and the manner in which the overrepresentation of radial orientations is accommodated in the functional architecture of visual cortex were also studied. Our results are based on an analysis of the orientations of the dendritic fields of 1296 ganglion cells throughout the retina and the preferred orientations of 1389 cells located in retinotopically corresponding regions of cortical areas 17, 18, and 19 in the cat. We find that horizontal and vertical orientations are overrepresented in regions of both retina and visual cortex subserving the central 5 degrees of vision. The distributions of the orientations of retinal ganglion cells and cortical cells subserving the horizontal, vertical, and diagonal meridians outside the area centralis differ significantly. The distribution of the preferred orientations of the S (simple) cells in areas 17, 18 and 19 subserving a given part of the retina corresponds to the distribution of the dendritic field orientations of the ganglion cells in that part of retina. The distribution of the preferred orientations of C (complex) cells with narrow receptive fields in area 17 but not C cells with wide receptive fields in areas 17, 18, or 19 subserving a given part of the retina matches the distribution of the orientations of the ganglion cells in that part of retina. The orientations of all of the alpha-cells in 5-9 mm2 patches of retina along the horizontal, vertical, and oblique meridians were determined. A comparison of the orientations of neighboring cells indicates that other than a mutual tendency to be oriented radially, ganglion cells with similar orientations are not clustered in the retina. Reconstructions of electrode penetrations into regions of visual cortex representing peripheral retina indicate that columns subserving radial orientations are wider than those subserving nonradial orientations. Our results provide evidence that the distribution of the preferred orientations of simple cells in visual cortex subserving any region of the visual field matches the distribution of the orientations of the ganglion cells subserving the same region of the visual field.(ABSTRACT TRUNCATED AT 400 WORDS)

Superconducting spin valves controlled by spiral re-orientation in B20-family magnets

NASA Astrophysics Data System (ADS)

Pugach, N. G.; Safonchik, M.; Champel, T.; Zhitomirsky, M. E.; Lähderanta, E.; Eschrig, M.; Lacroix, C.

2017-10-01

We propose a superconducting spin-triplet valve, which consists of a superconductor and an itinerant magnetic material, with the magnet showing an intrinsic non-collinear order characterized by a wave vector that may be aligned in a few equivalent preferred directions under the control of a weak external magnetic field. Re-orienting the spiral direction allows one to controllably modify long-range spin-triplet superconducting correlations, leading to spin-valve switching behavior. Our results indicate that the spin-valve effect may be noticeable. This bilayer may be used as a magnetic memory element for cryogenic nanoelectronics. It has the following advantages in comparison to superconducting spin valves proposed previously: (i) it contains only one magnetic layer, which may be more easily fabricated and controlled; (ii) its ground states are separated by a potential barrier, which solves the "half-select" problem of the addressed switch of memory elements.

A novel approach to piecewise analytic agricultural machinery path reconstruction

NASA Astrophysics Data System (ADS)

Wörz, Sascha; Mederle, Michael; Heizinger, Valentin; Bernhardt, Heinz

2017-12-01

Before analysing machinery operation in fields, it has to be coped with the problem that the GPS signals of GPS receivers located on the machines contain measurement noise, are time-discrete, and the underlying physical system describing the positions, axial and absolute velocities, angular rates and angular orientation of the operating machines during the whole working time are unknown. This research work presents a new three-dimensional mathematical approach using kinematic relations based on control variables as Euler angular velocities and angles and a discrete target control problem, such that the state control function is given by the sum of squared residuals involving the state and control variables to get such a physical system, which yields a noise-free and piecewise analytic representation of the positions, velocities, angular rates and angular orientation. It can be used for a further detailed study and analysis of the problem of why agricultural vehicles operate in practice as they do.

Step-by-Step Design of an FPGA-Based Digital Compensator for DC/DC Converters Oriented to an Introductory Course

ERIC Educational Resources Information Center

Zumel, P.; Fernandez, C.; Sanz, M.; Lazaro, A.; Barrado, A.

2011-01-01

In this paper, a short introductory course to introduce field-programmable gate array (FPGA)-based digital control of dc/dc switching power converters is presented. Digital control based on specific hardware has been at the leading edge of low-medium power dc/dc switching converters in recent years. Besides industry's interest in this topic, from…

Gender Differentiation of Relationships Between Manifestations of Indirect Self-Destructiveness and Dimensions of Emotional Intelligence.

PubMed

Tsirigotis, Konstantinos; Łuczak, Joanna

2016-09-01

The aim of this study has been to explore the gender differentiation of relationships between individual manifestations of indirect self-destructiveness and particular dimensions of emotional intelligence. A population of 260 individuals (130 women and 130 men) aged 20-30 (mean age of 24.5) was studied by using the Polish version of the Chronic Self-Destructiveness Scale (CS-DS) and INTE, i.e. the Polish version of the Assessing Emotions Scale (AES). Manifestations of indirect self-destructiveness showed significant correlations with INTE variables, and those correlations were mainly negative. Relationships between specific dimensions of emotional intelligence and specific manifestations of self-destructiveness differed between women and men. One of the most important differences was the relationship between transgression and ability to recognize emotions. The knowledge of the differentiation of the above relationships may allow to orient prophylactic and therapeutic actions, and adjust them to the specific gender.

Sea lamprey orient toward a source of a synthesized pheromone using odor-conditioned rheotaxis

USGS Publications Warehouse

Johnson, Nicholas S.; Muhammad, Azizah; Thompson, Henry; Choi, Jongeun; Li, Weiming

2012-01-01

Characterization of vertebrate chemo-orientation strategies over long distances is difficult because it is often not feasible to conduct highly controlled hypothesis-based experiments in natural environments. To overcome the challenge, we couple in-stream behavioral observations of female sea lampreys (Petromyzon marinus) orienting to plumes of a synthesized mating pheromone, 7a,12a,24-trihydroxy-5a-cholan-3-one-24-sulfate (3kPZS), and engineering algorithms to systematically test chemo-orientation hypotheses. In-stream field observations and simulated movements of female sea lampreys according to control algorithms support that odor-conditioned rheotaxis is a component of the mechanism used to track plumes of 3kPZS over hundreds of meters in flowing water. Simulated movements of female sea lampreys do not support that rheotaxis or klinotaxis alone is sufficient to enable the movement patterns displayed by females in locating 3kPZS sources in the experimental stream. Odor-conditioned rheotaxis may not only be effective at small spatial scales as previous described in crustaceans, but may also be effectively used by fishes over hundreds of meters. These results may prove useful for developing management strategies for the control of invasive species that exploit the odor-conditioned tracking behavior and for developing biologically inspired navigation strategies for robotic fish.

The geomagnetic environment in which sea turtle eggs incubate affects subsequent magnetic navigation behaviour of hatchlings.

PubMed

Fuxjager, Matthew J; Davidoff, Kyla R; Mangiamele, Lisa A; Lohmann, Kenneth J

2014-09-22

Loggerhead sea turtle hatchlings (Caretta caretta) use regional magnetic fields as open-ocean navigational markers during trans-oceanic migrations. Little is known, however, about the ontogeny of this behaviour. As a first step towards investigating whether the magnetic environment in which hatchlings develop affects subsequent magnetic orientation behaviour, eggs deposited by nesting female loggerheads were permitted to develop in situ either in the natural ambient magnetic field or in a magnetic field distorted by magnets placed around the nest. In orientation experiments, hatchlings that developed in the normal ambient field oriented approximately south when exposed to a field that exists near the northern coast of Portugal, a direction consistent with their migratory route in the northeastern Atlantic. By contrast, hatchlings that developed in a distorted magnetic field had orientation indistinguishable from random when tested in the same north Portugal field. No differences existed between the two groups in orientation assays involving responses to orbital movements of waves or sea-finding, neither of which involves magnetic field perception. These findings, to our knowledge, demonstrate for the first time that the magnetic environment present during early development can influence the magnetic orientation behaviour of a neonatal migratory animal. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Mechanisms of two-color laser-induced field-free molecular orientation.

PubMed

Spanner, Michael; Patchkovskii, Serguei; Frumker, Eugene; Corkum, Paul

2012-09-14

Two mechanisms of two-color (ω+2ω) laser-induced field-free molecular orientation, based on the hyperpolarizability and ionization depletion, are explored and compared. The CO molecule is used as a computational example. While the hyperpolarizability mechanism generates small amounts of orientation at intensities below the ionization threshold, ionization depletion quickly becomes the dominant mechanism as soon as ionizing intensities are reached. Only the ionization mechanism leads to substantial orientation (e.g., on the order of ≳0.1). For intensities typical of laser-induced molecular alignment and orientation experiments, the two mechanisms lead to robust, characteristic timings of the field-free orientation wave-packet revivals relative to the alignment revivals and the revival time. The revival timings can be used to detect the active orientation mechanism experimentally.

Analog neural network control method proposed for use in a backup satellite control mode

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

Frigo, J.R.; Tilden, M.W.

1998-03-01

The authors propose to use an analog neural network controller implemented in hardware, independent of the active control system, for use in a satellite backup control mode. The controller uses coarse sun sensor inputs. The field of view of the sensors activate the neural controller, creating an analog dead band with respect to the direction of the sun on each axis. This network controls the orientation of the vehicle toward the sunlight to ensure adequate power for the system. The attitude of the spacecraft is stabilized with respect to the ambient magnetic field on orbit. This paper develops a modelmore » of the controller using real-time coarse sun sensor data and a dynamic model of a prototype system based on a satellite system. The simulation results and the feasibility of this control method for use in a satellite backup control mode are discussed.« less

Characteristics of a liquid-crystal-filled composite lattice terahertz bandgap fiber

NASA Astrophysics Data System (ADS)

Bai, Jinjun; Ge, Meilan; Wang, Shasha; Yang, Yanan; Li, Yong; Chang, Shengjiang

2018-07-01

A new type of terahertz fiber is presented based on composite lattice photonic crystal bandgap. The cladding is filled selectively with the nematic liquid crystal 5CB which is sensitive to the electric field. The terahertz wave can be modulated by using the electric field to control the orientation of liquid crystal molecules. The plane wave expansion method and the finite element method are employed to theoretically analyze bandgap characteristics, polarization characteristics, energy fraction and material absorption loss. The results show that this fiber structure can be used as tunable terahertz polarization controller.

Automatic estimation of retinal nerve fiber bundle orientation in SD-OCT images using a structure-oriented smoothing filter

NASA Astrophysics Data System (ADS)

Ghafaryasl, Babak; Baart, Robert; de Boer, Johannes F.; Vermeer, Koenraad A.; van Vliet, Lucas J.

2017-02-01

Optical coherence tomography (OCT) yields high-resolution, three-dimensional images of the retina. A better understanding of retinal nerve fiber bundle (RNFB) trajectories in combination with visual field data may be used for future diagnosis and monitoring of glaucoma. However, manual tracing of these bundles is a tedious task. In this work, we present an automatic technique to estimate the orientation of RNFBs from volumetric OCT scans. Our method consists of several steps, starting from automatic segmentation of the RNFL. Then, a stack of en face images around the posterior nerve fiber layer interface was extracted. The image showing the best visibility of RNFB trajectories was selected for further processing. After denoising the selected en face image, a semblance structure-oriented filter was applied to probe the strength of local linear structure in a discrete set of orientations creating an orientation space. Gaussian filtering along the orientation axis in this space is used to find the dominant orientation. Next, a confidence map was created to supplement the estimated orientation. This confidence map was used as pixel weight in normalized convolution to regularize the semblance filter response after which a new orientation estimate can be obtained. Finally, after several iterations an orientation field corresponding to the strongest local orientation was obtained. The RNFB orientations of six macular scans from three subjects were estimated. For all scans, visual inspection shows a good agreement between the estimated orientation fields and the RNFB trajectories in the en face images. Additionally, a good correlation between the orientation fields of two scans of the same subject was observed. Our method was also applied to a larger field of view around the macula. Manual tracing of the RNFB trajectories shows a good agreement with the automatically obtained streamlines obtained by fiber tracking.

Powering up with indirect reciprocity in a large-scale field experiment.

PubMed

Yoeli, Erez; Hoffman, Moshe; Rand, David G; Nowak, Martin A

2013-06-18

A defining aspect of human cooperation is the use of sophisticated indirect reciprocity. We observe others, talk about others, and act accordingly. We help those who help others, and we cooperate expecting that others will cooperate in return. Indirect reciprocity is based on reputation, which spreads by communication. A crucial aspect of indirect reciprocity is observability: reputation effects can support cooperation as long as peoples' actions can be observed by others. In evolutionary models of indirect reciprocity, natural selection favors cooperation when observability is sufficiently high. Complimenting this theoretical work are experiments where observability promotes cooperation among small groups playing games in the laboratory. Until now, however, there has been little evidence of observability's power to promote large-scale cooperation in real world settings. Here we provide such evidence using a field study involving 2413 subjects. We collaborated with a utility company to study participation in a program designed to prevent blackouts. We show that observability triples participation in this public goods game. The effect is over four times larger than offering a $25 monetary incentive, the company's previous policy. Furthermore, as predicted by indirect reciprocity, we provide evidence that reputational concerns are driving our observability effect. In sum, we show how indirect reciprocity can be harnessed to increase cooperation in a relevant, real-world public goods game.

Electronic structure and its external electric field modulation of PbPdO2 ultrathin slabs with (002) and (211) preferred orientations.

PubMed

Yang, Yanmin; Zhong, Kehua; Xu, Guigui; Zhang, Jian-Min; Huang, Zhigao

2017-07-31

The Electronic structure of PbPdO 2 with (002) and (211) preferred orientations were investigated using first-principles calculation. The calculated results indicate that, (002) and (211) orientations exhibit different electric field dependence of band-gap and carrier concentration. The small band gap and more sensitive electric field modulation of band gap were found in (002) orientation. Moreover, the electric field modulation of the resistivity up to 3-4 orders of magnitude is also observed in (002) slab, which reveals that origin of colossal electroresistance. Lastly, electric field modulation of band gap is well explained. This work should be significant for repeating the colossal electroresistance.

Liability of newness: assessing couple social support when starting a new business venture.

PubMed

Danes, Sharon M; Craft, Shonda M; Jang, Juyoung; Lee, Jinhee

2013-10-01

Study purpose was to investigate adapted social support instruments of nurturance and affiliation with male and female entrepreneurs and spouses starting a new business. Family Fundamental Interpersonal Relationship Orientation theory was the theoretical grounding. Business structure differed by entrepreneur gender in both direct and indirect spousal involvement. Both couple types were highly connected with their firms having high nurturance and affiliation scores. When couple discrepancies were compared, more male entrepreneur couples had shared meaning on business-oriented nurturance questions compared with female entrepreneur couples. The opposite was true for shared meaning on relationship-oriented nurturance. For all affiliation questions, more male entrepreneur couples had shared meaning than did female entrepreneur couples. Clinical applications of resulting instruments are discussed. © 2013 American Association for Marriage and Family Therapy.

Campus-Based Geographic Learning: A Field Oriented Teaching Scenario

ERIC Educational Resources Information Center

Jennings, Steven A.; Huber, Thomas P.

2003-01-01

The use of field classes and the need for university master planning are presented as a way to enhance learning. This field-oriented, goal-oriented approach to learning is proposed as a general model for university-level geographic education. This approach is presented for physical geography classes, but could also be applied to other subdivisions…

Interplanetary Magnetic Field Control of the Entry of Solar Energetic Particles into the Magnetosphere

NASA Technical Reports Server (NTRS)

Richard, R. L.; El-Alaoui, M.; Ashour-Abdalla, M.; Walker, R. J.

2002-01-01

We have investigated the entry of energetic ions of solar origin into the magnetosphere as a function of the interplanetary magnetic field orientation. We have modeled this entry by following high energy particles (protons and 3 He ions) ranging from 0.1 to 50 MeV in electric and magnetic fields from a global magnetohydrodynamic (MHD) model of the magnetosphere and its interaction with the solar wind. For the most part these particles entered the magnetosphere on or near open field lines except for some above 10 MeV that could enter directly by crossing field lines due to their large gyroradii. The MHD simulation was driven by a series of idealized solar wind and interplanetary magnetic field (IMF) conditions. It was found that the flux of particles in the magnetosphere and transport into the inner magnetosphere varied widely according to the IMF orientation for a constant upstream particle source, with the most efficient entry occurring under southward IMF conditions. The flux inside the magnetosphere could approach that in the solar wind implying that SEPs can contribute significantly to the magnetospheric energetic particle population during typical SEP events depending on the state of the magnetosphere.

Magnetic orientation in C. elegans relies on the integrity of the villi of the AFD magnetosensory neurons.

PubMed

Bainbridge, Chance; Rodriguez, Anjelica; Schuler, Andrew; Cisneros, Michael; Vidal-Gadea, Andrés G

2016-10-01

The magnetic field of the earth provides many organisms with sufficient information to successfully navigate through their environments. While evidence suggests the widespread use of this sensory modality across many taxa, it remains an understudied sensory modality. We have recently showed that the nematode C. elegans orients to earth-strength magnetic fields using the first pair of described magnetosensory neurons, AFDs. The AFD cells are a pair of ciliated sensory neurons crowned by fifty villi known to be implicated in temperature sensation. We investigated the potential importance of these subcellular structures for the performance of magnetic orientation. We show that ciliary integrity and villi number are essential for magnetic orientation. Mutants with impairments AFD cilia or villi structure failed to orient to magnetic fields. Similarly, C. elegans larvae possessing immature AFD neurons with fewer villi were also unable to orient to magnetic fields. Larvae of every stage however retained the ability to orient to thermal gradients. To our knowledge, this is the first behavioral separation of magnetic and thermal orientation in C. elegans. We conclude that magnetic orientation relies on the function of both cilia and villi in the AFD neurons. The role of villi in multiple sensory transduction pathways involved in the sensory transduction of vectorial stimuli further supports the likely role of the villi of the AFD neurons as the site for magnetic field transduction. The genetic and behavioral tractability of C. elegans make it a promising system for uncovering potentially conserved molecular mechanisms by which animals across taxa detect and orient to magnetic fields. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of Building Energy Saving Through the Development of Venetian Blinds' Optimal Control Algorithm According to the Orientation and Window-to-Wall Ratio

NASA Astrophysics Data System (ADS)

Kwon, Hyuk Ju; Yeon, Sang Hun; Lee, Keum Ho; Lee, Kwang Ho

2018-02-01

As various studies focusing on building energy saving have been continuously conducted, studies utilizing renewable energy sources, instead of fossil fuel, are needed. In particular, studies regarding solar energy are being carried out in the field of building science; in order to utilize such solar energy effectively, solar radiation being brought into the indoors should be acquired and blocked properly. Blinds are a typical solar radiation control device that is capable of controlling indoor thermal and light environments. However, slat-type blinds are manually controlled, giving a negative effect on building energy saving. In this regard, studies regarding the automatic control of slat-type blinds have been carried out for the last couple of decades. Therefore, this study aims to provide preliminary data for optimal control research through the controlling of slat angle in slat-type blinds by comprehensively considering various input variables. The window area ratio and orientation were selected as input variables. It was found that an optimal control algorithm was different among each window-to-wall ratio and window orientation. In addition, through comparing and analyzing the building energy saving performance for each condition by applying the developed algorithms to simulations, up to 20.7 % energy saving was shown in the cooling period and up to 12.3 % energy saving was shown in the heating period. In addition, building energy saving effect was greater as the window area ratio increased given the same orientation, and the effects of window-to-wall ratio in the cooling period were higher than those of window-to-wall ratio in the heating period.

Weak extremely-low-frequency magnetic fields and regeneration in the planarian Dugesia tigrina

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

Jenrow, K.A.; Smith, C.H.; Liboff, A.R.

1995-06-01

Extremely-low-frequency (ELF), low-intensity magnetic fields have been shown to influence cell signaling processes in a variety of systems, both in vivo and in vitro. Similar effects have been demonstrated for nervous system development and neurite outgrowth. The authors report that regeneration in planaria, which incorporates many of these processes, is also affected by ELF magnetic fields. The rate of cephalic regeneration, reflected by the mean regeneration time (MRT), for planaria populations regenerating under continuous exposure to combined DC (78.4 {mu}T) and AC (60.0 Hz at 10.0 {mu}T{sub peak}) magnetic fields applied in parallel was found to be significantly delayed (Pmore » {much_lt} 0.001) by 48 {+-} 1 h relative to two different types of control populations (MRT {minus}140 {+-} 12 h). One control population was exposed to only the AC component of this field combination, while the other experienced only the ambient geomagnetic field. All measurements were conducted in a low-gradient, low-noise magnetics laboratory under well-maintained temperature conditions. This delay in regeneration was shown to be dependent on the planaria having a fixed orientation with respect to the magnetic field vectors. Results also indicate that this orientation-dependent transduction process does not result from Faraday induction but is consistent with a Ca{sup 2+} cyclotron resonance mechanism. Data interpretation also permits the tentative conclusion that the effect results from an inhibition of events at an early stage in the regeneration process before the onset of proliferation and differentiation.« less

COBRA, an Arabidopsis Extracellular Glycosyl-Phosphatidyl Inositol-Anchored Protein, Specifically Controls Highly Anisotropic Expansion through Its Involvement in Cellulose Microfibril OrientationW⃞

PubMed Central

Roudier, François; Fernandez, Anita G.; Fujita, Miki; Himmelspach, Regina; Borner, Georg H.H.; Schindelman, Gary; Song, Shuang; Baskin, Tobias I.; Dupree, Paul; Wasteneys, Geoffrey O.; Benfey, Philip N.

2005-01-01

The orientation of cell expansion is a process at the heart of plant morphogenesis. Cellulose microfibrils are the primary anisotropic material in the cell wall and thus are likely to be the main determinant of the orientation of cell expansion. COBRA (COB) has been identified previously as a potential regulator of cellulose biogenesis. In this study, characterization of a null allele, cob-4, establishes the key role of COB in controlling anisotropic expansion in most developing organs. Quantitative polarized-light and field-emission scanning electron microscopy reveal that loss of anisotropic expansion in cob mutants is accompanied by disorganization of the orientation of cellulose microfibrils and subsequent reduction of crystalline cellulose. Analyses of the conditional cob-1 allele suggested that COB is primarily implicated in microfibril deposition during rapid elongation. Immunodetection analysis in elongating root cells revealed that, in agreement with its substitution by a glycosylphosphatidylinositol anchor, COB was polarly targeted to both the plasma membrane and the longitudinal cell walls and was distributed in a banding pattern perpendicular to the longitudinal axis via a microtubule-dependent mechanism. Our observations suggest that COB, through its involvement in cellulose microfibril orientation, is an essential factor in highly anisotropic expansion during plant morphogenesis. PMID:15849274

COBRA, an Arabidopsis extracellular glycosyl-phosphatidyl inositol-anchored protein, specifically controls highly anisotropic expansion through its involvement in cellulose microfibril orientation.

PubMed

Roudier, François; Fernandez, Anita G; Fujita, Miki; Himmelspach, Regina; Borner, Georg H H; Schindelman, Gary; Song, Shuang; Baskin, Tobias I; Dupree, Paul; Wasteneys, Geoffrey O; Benfey, Philip N

2005-06-01

The orientation of cell expansion is a process at the heart of plant morphogenesis. Cellulose microfibrils are the primary anisotropic material in the cell wall and thus are likely to be the main determinant of the orientation of cell expansion. COBRA (COB) has been identified previously as a potential regulator of cellulose biogenesis. In this study, characterization of a null allele, cob-4, establishes the key role of COB in controlling anisotropic expansion in most developing organs. Quantitative polarized-light and field-emission scanning electron microscopy reveal that loss of anisotropic expansion in cob mutants is accompanied by disorganization of the orientation of cellulose microfibrils and subsequent reduction of crystalline cellulose. Analyses of the conditional cob-1 allele suggested that COB is primarily implicated in microfibril deposition during rapid elongation. Immunodetection analysis in elongating root cells revealed that, in agreement with its substitution by a glycosylphosphatidylinositol anchor, COB was polarly targeted to both the plasma membrane and the longitudinal cell walls and was distributed in a banding pattern perpendicular to the longitudinal axis via a microtubule-dependent mechanism. Our observations suggest that COB, through its involvement in cellulose microfibril orientation, is an essential factor in highly anisotropic expansion during plant morphogenesis.

Rejection Sensitivity and Depression: Indirect Effects Through Problem Solving.

PubMed

Kraines, Morganne A; Wells, Tony T

2017-01-01

Rejection sensitivity (RS) and deficits in social problem solving are risk factors for depression. Despite their relationship to depression and the potential connection between them, no studies have examined RS and social problem solving together in the context of depression. As such, we examined RS, five facets of social problem solving, and symptoms of depression in a young adult sample. A total of 180 participants completed measures of RS, social problem solving, and depressive symptoms. We used bootstrapping to examine the indirect effect of RS on depressive symptoms through problem solving. RS was positively associated with depressive symptoms. A negative problem orientation, impulsive/careless style, and avoidance style of social problem solving were positively associated with depressive symptoms, and a positive problem orientation was negatively associated with depressive symptoms. RS demonstrated an indirect effect on depressive symptoms through two social problem-solving facets: the tendency to view problems as threats to one's well-being and an avoidance problem-solving style characterized by procrastination, passivity, or overdependence on others. These results are consistent with prior research that found a positive association between RS and depression symptoms, but this is the first study to implicate specific problem-solving deficits in the relationship between RS and depression. Our results suggest that depressive symptoms in high RS individuals may result from viewing problems as threats and taking an avoidant, rather than proactive, approach to dealing with problems. These findings may have implications for problem-solving interventions for rejection sensitive individuals.

Electroelastic fields in artificially created vortex cores in epitaxial BiFeO 3 thin films

DOE PAGES

Winchester, Ben; Wisinger, Nina Balke; Cheng, X. X.; ...

2015-08-03

Here we employ phase-field modeling to explore the elastic properties of artificially created 1-D domain walls in (001) p-oriented BiFeO 3 thin films, composed of a junction of the four polarization variants, all with the same out-of-plane polarization. It was found that these junctions exhibit peculiarly high electroelastic fields induced by the neighboring ferroelastic/ferroelectric domains. The vortex core exhibits a volume expansion, while the anti-vortex core is more compressive. We also discuss possible ways to control the electroelastic field, such as varying material constant and applying transverse electric field.

Cooperative ordering and kinetics of cellulose nanocrystal alignment in a magnetic field

DOE PAGES

De France, Kevin J.; Yager, Kevin G.; Hoare, Todd; ...

2016-07-13

Cellulose nanocrystals (CNCs) are emerging nanomaterials that form chiral nematic liquid crystals above a critical concentration (C*) and additionally orient within electromagnetic fields. The control over CNC alignment is significant for materials processing and end use; to date, magnetic alignment has been demonstrated using only strong fields over extended or arbitrary time scales. This work investigates the effects of comparatively weak magnetic fields (0–1.2 T) and CNC concentration (1.65–8.25 wt %) on the kinetics and degree of CNC ordering using small-angle X-ray scattering. Interparticle spacing, correlation length, and orientation order parameters (η and S) increased with time and field strengthmore » following a sigmoidal profile. In a 1.2 T magnetic field for CNC suspensions above C*, partial alignment occurred in under 2 min followed by slower cooperative ordering to achieve nearly perfect alignment in under 200 min (S = –0.499 where S = –0.5 indicates perfect antialignment). At 0.56 T, nearly perfect alignment was also achieved, yet the ordering was 36% slower. Outside of a magnetic field, the order parameter plateaued at 52% alignment (S = –0.26) after 5 h, showcasing the drastic effects of relatively weak magnetic fields on CNC alignment. For suspensions below C*, no magnetic alignment was detected.« less

Patients Know Best: Qualitative Study on How Families Use Patient-Controlled Personal Health Records

PubMed Central

Schneider, Hanna; Hill, Susan

2016-01-01

Background Self-management technologies, such as patient-controlled electronic health records (PCEHRs), have the potential to help people manage and cope with disease. Objective This study set out to investigate patient families’ lived experiences of working with a PCEHR. Methods We conducted a semistructured qualitative field study with patient families and clinicians at a children’s hospital in the UK that uses a PCEHR (Patients Know Best). All families were managing the health of a child with a serious chronic condition, who was typically under the care of multiple clinicians. As data gathering and analysis progressed, it became clear that while much of the literature assumes that patients are willing and waiting to take more responsibility for and control over their health management (eg, with PCEHRs), only a minority of participants in our study responded in this way. Their experiences with the PCEHR were diverse and strongly shaped by their coping styles. Theory on coping identifies a continuum of coping styles, from approach to avoidance oriented, and proposes that patients’ information needs depend on their style. Results We identified 3 groups of patient families and an outlier, distinguished by their coping style and their PCEHR use. We refer to the outlier as controlling (approach oriented, highly motivated to use PCEHR), and the 3 groups as collaborating (approach oriented, motivated to use PCEHR), cooperating (avoidance oriented, less motivated to use PCEHR), and avoiding (very avoidance oriented, not motivated to use PCEHR). Conclusions The PCEHR met the needs of controller and collaborators better than the needs of cooperators and avoiders. We draw on the Self-Determination Theory to propose ways in which a PCEHR design might better meet the needs of avoidance-oriented users. Further, we highlight the need for families to also relinquish control at times, and propose ways in which PCEHR design might support a better distribution of control, based on effective training, ease of use, comprehensibility of data security mechanisms, timely information provision (recognizing people’s different needs), personalization of use, and easy engagement with clinicians through the PCEHR. PMID:26912201

Sensory-Motor Adaptation to Space Flight: Human Balance Control and Artificial Gravity

NASA Technical Reports Server (NTRS)

Paloski, William H.

2004-01-01

Gravity, which is sensed directly by the otolith organs and indirectly by proprioceptors and exteroceptors, provides the CNS a fundamental reference for estimating spatial orientation and coordinating movements in the terrestrial environment. The sustained absence of gravity during orbital space flight creates a unique environment that cannot be reproduced on Earth. Loss of this fundamental CNS reference upon insertion into orbit triggers neuro-adaptive processes that optimize performance for the microgravity environment, while its reintroduction upon return to Earth triggers neuro-adaptive processes that return performance to terrestrial norms. Five pioneering symposia on The Role of the Vestibular Organs in the Exploration of Space were convened between 1965 and 1970. These innovative meetings brought together the top physicians, physiologists, and engineers in the vestibular field to discuss and debate the challenges associated with human vestibular system adaptation to the then novel environment of space flight. These highly successful symposia addressed the perplexing problem of how to understand and ameliorate the adverse physiological effects on humans resulting from the reduction of gravitational stimulation of the vestibular receptors in space. The series resumed in 2002 with the Sixth Symposium, which focused on the microgravity environment as an essential tool for the study of fundamental vestibular functions. The three day meeting included presentations on historical perspectives, vestibular neurobiology, neurophysiology, neuroanatomy, neurotransmitter systems, theoretical considerations, spatial orientation, psychophysics, motor integration, adaptation, autonomic function, space motion sickness, clinical issues, countermeasures, and rehabilitation. Scientists and clinicians entered into lively exchanges on how to design and perform mutually productive research and countermeasure development projects in the future. The problems posed by long duration missions dominated these discussions and were driven by the paucity of data available. These issues along with more specific recommendations arising from the above discussions will be addressed an upcoming issue of the Journal of Vestibular Research.

Domains of State-Owned, Privately Held, and Publicly Traded Firms in International Competition.

ERIC Educational Resources Information Center

Mascarenhas, Briance

1989-01-01

Hypotheses relating ownership to domain differences among state-owned, publicly traded, and privately held firms in international competition were examined in a controlled field study of the offshore drilling industry. Ownership explained selected differences in domestic market dominance, international presence, and customer orientation, even…

CNC Turning Technician. A Competency-Based Instructional System.

ERIC Educational Resources Information Center

Sloan, Kelly; Hilley, Robert

This competency-based curriculum guide for instructing students in using computer numerically controlled (CNC) turning machines is one of a series of instructional guides for the machinist field developed in Oklahoma. Although developed jointly with Baxter Technologies Corporation and oriented toward the Baxter Vo-Tec 2000 Future Builder CNC…

Digital telephony analysis model and issues

NASA Astrophysics Data System (ADS)

Keuthan, Lynn M.

1995-09-01

Experts in the fields of digital telephony and communications security have stated the need for an analytical tool for evaluating complex issues. Some important policy issues discussed by experts recently include implementing digital wire-taps, implementation of the 'Clipper Chip', required registration of encryption/decryption keys, and export control of cryptographic equipment. Associated with the implementation of these policies are direct costs resulting from implementation, indirect cost benefits from implementation, and indirect costs resulting from the risks of implementation or factors reducing cost benefits. Presented herein is a model for analyzing digital telephony policies and systems and their associated direct costs and indirect benefit and risk factors. In order to present the structure of the model, issues of national importance and business-related issues are discussed. The various factors impacting the implementation of the associated communications systems and communications security are summarized, and various implementation tradeoffs are compared based on economic benefits/impact. The importance of the issues addressed herein, as well as other digital telephony issues, has greatly increased with the enormous increases in communication system connectivity due to the advance of the National Information Infrastructure.

Measuring Filament Orientation: A New Quantitative, Local Approach

NASA Astrophysics Data System (ADS)

Green, C.-E.; Dawson, J. R.; Cunningham, M. R.; Jones, P. A.; Novak, G.; Fissel, L. M.

2017-09-01

The relative orientation between filamentary structures in molecular clouds and the ambient magnetic field provides insight into filament formation and stability. To calculate the relative orientation, a measurement of filament orientation is first required. We propose a new method to calculate the orientation of the one-pixel-wide filament skeleton that is output by filament identification algorithms such as filfinder. We derive the local filament orientation from the direction of the intensity gradient in the skeleton image using the Sobel filter and a few simple post-processing steps. We call this the “Sobel-gradient method.” The resulting filament orientation map can be compared quantitatively on a local scale with the magnetic field orientation map to then find the relative orientation of the filament with respect to the magnetic field at each point along the filament. It can also be used for constructing radial profiles for filament width fitting. The proposed method facilitates automation in analyses of filament skeletons, which is imperative in this era of “big data.”

The organization of orientation selectivity throughout macaque visual cortex.

PubMed

Vanduffel, Wim; Tootell, Roger B H; Schoups, Aniek A; Orban, Guy A

2002-06-01

A double-label deoxyglucose technique was used to study orientation columns throughout visual cortex in awake behaving macaques. Four macaques were trained to fixate while contrastreversing, stationary gratings or one-dimensional noise of a single orientation or an orthogonal orientation were presented, during uptake of [14C]deoxyglucose ([14C]DG) or [3H]DG, respectively. The two orthogonal stimulus orientations produced DG-labeled columns that were maximally separated in the two isotope maps (inter-digitated) in four areas: V1, V2, V3 and VP. The topographic change from interdigitated to overlapping columns occurred abruptly rather than gradually, at corresponding cortical area borders (e.g. VP and V4v, respectively). In addition, the data suggest that orientation column topography systematically changes with retinotopic eccentricity. In V1, the orientation columns systematically avoided the cytochrome oxidase blobs in the parafoveal representation, but converged closer to the blobs in the foveal representation. A control experiment indicated that this was unlikely to reflect eccentricity-dependent differences in cortical spatial frequency sensitivity. A similar eccentricity-dependent change in the topography of orientation columns occurred in V2. In parafoveal but not foveal visual field representations of V2, the orientation columns were centered on the thick cytochrome oxidase stripes, extended into the adjacent interstripe region, but were virtually absent in the thin stripes.

Sexual orientation and alcohol problem use among U.K. adolescents: an indirect link through depressed mood.

PubMed

Pesola, Francesca; Shelton, Katherine H; van den Bree, Marianne B M

2014-07-01

Sexual minority adolescents are more likely to engage in alcohol use than their heterosexual counterparts; however, the underlying reasons remain unclear and longitudinal research is limited. Owing to evidence that this group also experiences greater depressive symptoms than their peers, we aimed to (i) assess to what extent depressed mood explains the increased likelihood of engaging in alcohol use among sexual minority adolescents, and (ii) explore potential gender-specific patterns. Structural equation modelling was used to test the indirect relationship between sexual orientation and alcohol use through depressed mood, with heterosexuals as the reference group. A total of 3710 adolescents (12% sexual minority), from the Avon Longitudinal Study of Parents and Children (ALSPAC) study, assessed between the ages of 15 and 18 years. Sexual orientation was assessed at age 15, while alcohol use was measured using the Alcohol Use Disorders Identification Test (AUDIT) at age 18. Depressed mood was indexed by the Short Mood and Feelings Questionnaire (SMFQ) at age 16. Sexual minority adolescents were more likely to engage in alcohol problem use compared to their heterosexual counterparts [Btotal  = 0.12, 95% confidence interval (CI) = 0.04-0.20, P = 0.003]. Depressed mood explained 21% of the link between sexual orientation and alcohol use after adjustment for covariates and earlier measures (Z = 3.2, P = 0.001). No gender differences were observed. A higher prevalence of alcohol problem use in adolescents who are gay, lesbian or bisexual is partly explained by increased rates of depression in this group. © 2014 Society for the Study of Addiction.

Position and Orientation Insensitive Wireless Power Transmission for EnerCage-Homecage System.

PubMed

Jia, Yaoyao; Mirbozorgi, S Abdollah; Wang, Zheyuan; Hsu, Chia-Chun; Madsen, Teresa E; Rainnie, Donald; Ghovanloo, Maysam

2017-10-01

We have developed a new headstage architecture as part of a smart experimental arena, known as the EnerCage-HC2 system, which automatically delivers stimulation and collects behavioral data over extended periods with minimal small animal subject handling or personnel intervention in a standard rodent homecage. Equipped with a four-coil inductive link, the EnerCage-HC2 system wirelessly powers the receiver (Rx) headstage, irrespective of the subject's location or head orientation, eliminating the need for tethering or carrying bulky batteries. On the transmitter (Tx) side, a driver coil, five high-quality (Q) factor segmented resonators at different heights and orientations, and a closed-loop Tx power controller create a homogeneous electromagnetic (EM) field within the homecage 3-D space, and compensate for drops in power transfer efficiency (PTE) due to Rx misalignments. The headstage is equipped with four small slanted resonators, each covering a range of head orientations with respect to the Tx resonators, which direct the EM field toward the load coil at the bottom of the headstage. Moreover, data links based on Wi-Fi, UART, and Bluetooth low energy are utilized to enables remote communication and control of the Rx. The PTE varies within 23.6%-33.3% and 6.7%-10.1% at headstage heights of 8 and 20 cm, respectively, while continuously delivering >40 mW to the Rx electronics even at 90° rotation. As a proof of EnerCage-HC2 functionality in vivo, a previously documented on-demand electrical stimulation of the globus pallidus, eliciting consistent head rotation, is demonstrated in three freely behaving rats.

Geometrical Relationship Between Interplanetary Flux Ropes and Their Solar Sources

NASA Astrophysics Data System (ADS)

Marubashi, K.; Akiyama, S.; Yashiro, S.; Gopalswamy, N.; Cho, K.-S.; Park, Y.-D.

2015-05-01

We investigated the physical connection between interplanetary flux ropes (IFRs) near Earth and coronal mass ejections (CMEs) by comparing the magnetic field structures of IFRs and CME source regions. The analysis is based on the list of 54 pairs of ICMEs (interplanetary coronal mass ejections) and CMEs that are taken to be the most probable solar source events. We first attempted to identify the flux rope structure in each of the 54 ICMEs by fitting models with a cylinder and torus magnetic field geometry, both with a force-free field structure. This analysis determined the possible geometries of the identified flux ropes. Then we compared the flux rope geometries with the magnetic field structure of the solar source regions. We obtained the following results: (1) Flux rope structures are seen in 51 ICMEs out of the 54. The result implies that all ICMEs have an intrinsic flux rope structure, if the three exceptional cases are attributed to unfavorable observation conditions. (2) It is possible to find flux rope geometries with the main axis orientation close to the orientation of the magnetic polarity inversion line (PIL) in the solar source regions, the differences being less than 25°. (3) The helicity sign of an IFR is strongly controlled by the location of the solar source: flux ropes with positive (negative) helicity are associated with sources in the southern (northern) hemisphere (six exceptions were found). (4) Over two-thirds of the sources in the northern hemisphere are concentrated along PILs with orientations of 45° ± 30° (measured clockwise from the east), and over two-thirds in the southern hemisphere along PILs with orientations of 135° ± 30°, both corresponding to the Hale boundaries. These results strongly support the idea that a flux rope with the main axis parallel to the PIL erupts in a CME and that the erupted flux rope propagates through the interplanetary space with its orientation maintained and is observed as an IFR.

Development of a model osseo-magnetic link for intuitive rotational control of upper-limb prostheses.

PubMed

Rouse, Elliott J; Nahlik, David C; Peshkin, Michael A; Kuiken, Todd A

2011-04-01

The lack of proprioceptive feedback is a serious deficiency of current prosthetic control systems. The Osseo-Magnetic Link (OML) is a novel humeral or wrist rotation control system that could preserve proprioception. It utilizes a magnet implanted within the residual bone and sensors mounted in the prosthetic socket to detect magnetic field vectors and determine the bone's orientation. This allows the use of volitional bone rotation to control a prosthetic rotator. We evaluated the performance of the OML using a physical model of a transhumeral residual limb. A small Neodymium-Iron-Boron magnet was placed in a model humerus, inside a model upper arm. Four three-axis Hall-effect sensors were mounted on a ring 3 cm distal to the magnet. An optimization algorithm based on Newton's method determined the position and orientation of the magnet within the model humerus under various conditions, including bone translations, interference, and magnet misalignment. The orientation of the model humerus was determined within 3° for rotations centered in the arm; an additional 6° error was found for translations 20 mm from center. Adjustments in sensor placement may reduce these errors. The results demonstrate that the OML is a feasible solution for providing prosthesis rotation control while preserving rotational proprioception.

Control methods and systems for indirect evaporative coolers

DOEpatents

Woods, Jason; Kozubal, Erik

2015-09-22

A control method for operating an indirect evaporative cooler to control temperature and humidity. The method includes operating an airflow control device to provide supply air at a flow rate to a liquid desiccant dehumidifier. The supply air flows through the dehumidifier and an indirect evaporative cooler prior to exiting an outlet into a space. The method includes operating a pump to provide liquid desiccant to the liquid desiccant dehumidifier and sensing a temperature of an airstream at the outlet of the indirect evaporative cooler. The method includes comparing the temperature of the airstream at the outlet to a setpoint temperature at the outlet and controlling the pump to set the flow rate of the liquid desiccant. The method includes sensing space temperature, comparing the space temperature with a setpoint temperature, and controlling the airflow control device to set the flow rate of the supply air based on the comparison.

Nerve Cells Decide to Orient inside an Injectable Hydrogel with Minimal Structural Guidance.

PubMed

Rose, Jonas C; Cámara-Torres, María; Rahimi, Khosrow; Köhler, Jens; Möller, Martin; De Laporte, Laura

2017-06-14

Injectable biomaterials provide the advantage of a minimally invasive application but mostly lack the required structural complexity to regenerate aligned tissues. Here, we report a new class of tissue regenerative materials that can be injected and form an anisotropic matrix with controlled dimensions using rod-shaped, magnetoceptive microgel objects. Microgels are doped with small quantities of superparamagnetic iron oxide nanoparticles (0.0046 vol %), allowing alignment by external magnetic fields in the millitesla order. The microgels are dispersed in a biocompatible gel precursor and after injection and orientation are fixed inside the matrix hydrogel. Regardless of the low volume concentration of the microgels below 3%, at which the geometrical constrain for orientation is still minimum, the generated macroscopic unidirectional orientation is strongly sensed by the cells resulting in parallel nerve extension. This finding opens a new, minimal invasive route for therapy after spinal cord injury.

Effect of nanostructures orientation on electroosmotic flow in a microfluidic channel

NASA Astrophysics Data System (ADS)

Eng Lim, An; Lim, Chun Yee; Cheong Lam, Yee; Taboryski, Rafael; Rui Wang, Shu

2017-06-01

Electroosmotic flow (EOF) is an electric-field-induced fluid flow that has numerous micro-/nanofluidic applications, ranging from pumping to chemical and biomedical analyses. Nanoscale networks/structures are often integrated in microchannels for a broad range of applications, such as electrophoretic separation of biomolecules, high reaction efficiency catalytic microreactors, and enhancement of heat transfer and sensing. Their introduction has been known to reduce EOF. Hitherto, a proper study on the effect of nanostructures orientation on EOF in a microfluidic channel is yet to be carried out. In this investigation, we present a novel fabrication method for nanostructure designs that possess maximum orientation difference, i.e. parallel versus perpendicular indented nanolines, to examine the effect of nanostructures orientation on EOF. It consists of four phases: fabrication of silicon master, creation of mold insert via electroplating, injection molding with cyclic olefin copolymer, and thermal bonding and integration of practical inlet/outlet ports. The effect of nanostructures orientation on EOF was studied experimentally by current monitoring method. The experimental results show that nanolines which are perpendicular to the microchannel reduce the EOF velocity significantly (approximately 20%). This flow velocity reduction is due to the distortion of local electric field by the perpendicular nanolines at the nanostructured surface as demonstrated by finite element simulation. In contrast, nanolines which are parallel to the microchannel have no effect on EOF, as it can be deduced that the parallel nanolines do not distort the local electric field. The outcomes of this investigation contribute to the precise control of EOF in lab-on-chip devices, and fundamental understanding of EOF in devices which utilize nanostructured surfaces for chemical and biological analyses.

Unravelling changing interspecific interactions across environmental gradients using Markov random fields.

PubMed

Clark, Nicholas J; Wells, Konstans; Lindberg, Oscar

2018-05-16

Inferring interactions between co-occurring species is key to identify processes governing community assembly. Incorporating interspecific interactions in predictive models is common in ecology, yet most methods do not adequately account for indirect interactions (where an interaction between two species is masked by their shared interactions with a third) and assume interactions do not vary along environmental gradients. Markov random fields (MRF) overcome these limitations by estimating interspecific interactions, while controlling for indirect interactions, from multispecies occurrence data. We illustrate the utility of MRFs for ecologists interested in interspecific interactions, and demonstrate how covariates can be included (a set of models known as Conditional Random Fields, CRF) to infer how interactions vary along environmental gradients. We apply CRFs to two data sets of presence-absence data. The first illustrates how blood parasite (Haemoproteus, Plasmodium, and nematode microfilaria spp.) co-infection probabilities covary with relative abundance of their avian hosts. The second shows that co-occurrences between mosquito larvae and predatory insects vary along water temperature gradients. Other applications are discussed, including the potential to identify replacement or shifting impacts of highly connected species along climate or land-use gradients. We provide tools for building CRFs and plotting/interpreting results as an R package. © 2018 by the Ecological Society of America.

PIV-based estimation of unsteady loads on a flat plate at high angle of attack using momentum equation approaches

NASA Astrophysics Data System (ADS)

Guissart, Amandine; Bernal, Luis; Dimitriadis, Gregorios; Terrapon, Vincent

2015-11-01

The direct measurement of loads with force balance can become challenging when the forces are small or when the body is moving. An alternative is the use of Particle Image Velocimetry (PIV) velocity fields to indirectly obtain the aerodynamic coefficients. This can be done by the use of control volume approaches which lead to the integration of velocities, and other fields deriving from them, on a contour surrounding the studied body and its supporting surface. This work exposes and discusses results obtained with two different methods: the direct use of the integral formulation of the Navier-Stokes equations and the so-called Noca's method. The latter is a reformulation of the integral Navier-Stokes equations in order to get rid of the pressure. Results obtained using the two methods are compared and the influence of different parameters is discussed. The methods are applied to PIV data obtained from water channel testing for the flow around a 16:1 plate. Two cases are considered: a static plate at high angle of attack and a large amplitude imposed pitching motion. Two-dimensional PIV velocity fields are used to compute the aerodynamic forces. Direct measurements of dynamic loads are also carried out in order to assess the quality of the indirectly calculated coefficients.

Mitigation of indirect environmental effects of GM crops

PubMed Central

Pidgeon, J.D; May, M.J; Perry, J.N; Poppy, G.M

2007-01-01

Currently, the UK has no procedure for the approval of novel agricultural practices that is based on environmental risk management principles. Here, we make a first application of the ‘bow-tie’ risk management approach in agriculture, for assessment of land use changes, in a case study of the introduction of genetically modified herbicide tolerant (GMHT) sugar beet. There are agronomic and economic benefits, but indirect environmental harm from increased weed control is a hazard. The Farm Scale Evaluation (FSE) trials demonstrated reduced broad-leaved weed biomass and seed production at the field scale. The simplest mitigation measure is to leave a proportion of rows unsprayed in each GMHT crop field. Our calculations, based on FSE data, show that a maximum of 2% of field area left unsprayed is required to mitigate weed seed production and 4% to mitigate weed biomass production. Tilled margin effects could simply be mitigated by increasing the margin width from 0.5 to 1.5 m. Such changes are cheap and simple to implement in farming practices. This case study demonstrates the usefulness of the bow-tie risk management approach and the transparency with which hazards can be addressed. If adopted generally, it would help to enable agriculture to adopt new practices with due environmental precaution. PMID:17439853

Quadratic stark effect in the fullerene C60 at low symmetry orientation in the field

NASA Astrophysics Data System (ADS)

Tuchin, A. V.; Bityutskaya, L. A.; Bormontov, E. N.

2014-08-01

Results of numeric simulation of the influence of the electric field E = 0 - 1 V/Å on the electronic structure of the neutral fullerene C60 taking into account orientational deformation of its carbon cage at arbitrary orientations in the electric field including low symmetry orientations are presented. Splitting of the frontier t 1 u - and h u -levels of the molecule due to the quadratic Stark effect has been investigated. Dependencies of the effective electron work function and the energy gap between the lowest unoccupied and highest occupied molecular orbitals on the strengths of the electric field have been determined.

Nanoscale control of stripe-ordered magnetic domain walls by vertical spin transfer torque in La0.67Sr0.33MnO3 film

NASA Astrophysics Data System (ADS)

Wang, Jing; Wu, Shizhe; Ma, Ji; Xie, Lishan; Wang, Chuanshou; Malik, Iftikhar Ahmed; Zhang, Yuelin; Xia, Ke; Nan, Ce-Wen; Zhang, Jinxing

2018-02-01

Stripe-ordered domains with perpendicular magnetic anisotropy have been intensively investigated due to their potential applications in high-density magnetic data-storage devices. However, the conventional control methods (e.g., epitaxial strain, local heating, magnetic field, and magnetoelectric effect) of the stripe-ordered domain walls either cannot meet the demands for miniaturization and low power consumption of spintronic devices or require high strength of the electric field due to the small value of the magnetoelectric effect at room temperature. Here, a domain-wall resistive effect of 0.1% was clarified in La0.67Sr0.33MnO3 thin films between the configurations of current in the plane and perpendicular to the plane of walls. Furthermore, a reversible nanoscale control of the domain-wall re-orientation by vertical spin transfer torque across the probe/film interface was achieved, where a probe voltage of 0.1 V was applied on a manganite-based capacitor. We also demonstrated that the stripe-ordered magnetic domain-wall re-orientation strongly depends on the AC frequency of the scanning probe voltage which was applied on the capacitor.

Controlling BaZrO3 nanostructure orientation in YBa2Cu3O{}_{7-\\delta } films for a three-dimensional pinning landscape

NASA Astrophysics Data System (ADS)

Wu, J. Z.; Shi, J. J.; Baca, F. J.; Emergo, R.; Wilt, J.; Haugan, T. J.

2015-12-01

The orientation phase diagram of self-assembled BaZrO3 (BZO) nanostructures in c-oriented YBa2Cu3O{}7-δ (YBCO) films on flat and vicinal SrTiO3 substrates was studied experimentally with different dopant concentrations and vicinal angles and theoretically using a micromechanical model based on the theory of elasticity. The organized BZO nanostructure configuration was found to be tunable, between c-axis to ab-plane alignment, by the dopant concentration in the YBCO film matrix strained via lattice mismatched substrates. The correlation between the local strain caused by the BZO doping and the global strain on the matrix provides a unique approach for controllable growth of dopant nanostructure landscapes. In particular, a mixed phase of the c-axis-aligned nanorods and the ab-plane-aligned planar nanostructures can be obtained, leading to a three-dimensional pinning landscape with single impurity doping and much improved J c in almost all directions of applied magnetic field.

Cholesteric-nematic transitions induced by a shear flow and a magnetic field

NASA Astrophysics Data System (ADS)

Zakhlevnykh, A. N.; Makarov, D. V.; Novikov, A. A.

2017-10-01

The untwisting of the helical structure of a cholesteric liquid crystal under the action of a magnetic field and a shear flow has been studied theoretically. Both factors can induce the cholesteric-nematic transition independently; however, the difference in the orienting actions of the magnetic field and the shear flow leads to competition between magnetic and hydrodynamic mechanisms of influence on the cholesteric liquid crystal. We have analyzed different orientations of the magnetic field relative to the direction of the flow in the shear plane. In a number of limiting cases, the analytic dependences are obtained for the pitch of the cholesteric helix deformed by the shear flow. The phase diagrams of the cholesteric-nematic transitions and the pitch of the cholesteric helix are calculated for different values of the magnetic field strength and the angle of orientation, the flow velocity gradient, and the reactive parameter. It is shown that the magnetic field stabilizes the orientation of the director in the shear flow and expands the boundaries of orientability of cholesterics. It has been established that the shear flow shifts the critical magnetic field strength of the transition. It is shown that a sequence of reentrant orientational cholesteric-nematic-cholesteric transitions can be induced by rotating the magnetic field in certain intervals of its strength and shear flow velocity gradients.

A Comparison of Student Outcomes in Various Earth Science Courses Taught by Seventeen Iowa Teachers.

ERIC Educational Resources Information Center

Schirner, Silas Wesley

The effects of the type of earth science course (Earth Science Curriculum Project (ESCP) and non-ESCP), the directness or indirectness of teacher-pupil interaction in various teaching activities (I/D ratio), and the teacher's philosophical orientation (T/NT ratio) on various student outcomes such as understanding of science and scientists;…

Versatile Clinical Application of the Spike Screw: Direct Anchorage Versus Indirect Anchorage.

PubMed

Kim, Kyung A; Chen, Yu; Kwon, Soon-Yong; Seo, Kyung Won; Park, Ki-Ho; Kim, Seong-Hun

2015-10-01

This article represents clinical application of spike screw, novel design of miniscrew, for direct anchorage and indirect anchorage in orthodontic treatment. Accompanied by easy placement and removal, the spike screw provides good stability for the orthodontic anchorage. The spike screw consists of 6 spikes attached to a washer with laser welded stainless-steel hook that is placed by self-drilling fixation miniscrew. The spike screws were applied to correct malocclusions in patients as follows: traction of impacted canines and protraction of posterior teeth as a direct anchorage and correction of midline discrepancy as an indirect anchorage. For orthodontic traction of impacted canines, spike screws were placed in the mandibular labial mucosal area to create extrusive forces. Afterward, it was utilized for the protraction of posterior teeth. In the second case of the indirect anchorage, spike screw was applied on the midpalatal area to correct midline discrepancy that occurred during orthodontic treatment. The extended hook of a washer was prebended along the curvature of the palate and then secured with a mini screw. The extended hook was bonded to maxillary left first molar. In the first case, the spike screw provided adequate anchorage for the vertical traction of horizontally impacted canine. Since the spike screws were placed in the mandibular anterior lesion, the vertical traction force was applied simply with orthodontic elastics. Also, enough distance was achieved for up-down elastics to work by placing the spike screw in the opposite arch. The force of vertical traction was adjusted with selection of size and force of up-down elastics. Later, it was used to provide anchorage for protraction of mandibular molars without changing orientation of the spike screws. In the second case, the spike screw placed in the midpalatal area was attached to the left first molar and worked as an indirect anchorage. The midline discrepancy was resolved by consolidating the spaces to the left with securing the left first molar location. The novel design of the spike screw permits clinicians to have minimum invasive and easy placement and removal of the appliance while maintaining a good control over tooth movement with improved stability in various clinical cases.

The use of the geomagnetic field for short distance orientation in zebra finches.

PubMed

Voss, Joe; Keary, Nina; Bischof, Hans-Joachim

2007-07-02

Although the ability to use the Earth's magnetic field for long distance orientation and navigation has been demonstrated in many animals, the search for the appropriate receptor has not yet finished. It is also not entirely clear whether the use of magnetic field information is restricted to specialists like migrating birds, or whether it is a sense that is also suited to short distance orientation by avian species. We successfully trained nonmigratory zebra finches in a four-choice food-search task to use the natural magnetic field as well as an experimentally shifted field for short distance orientation, supporting the view that magnetic field perception may be a sense existing in all bird species. By using a conditioning technique in a standard laboratory animal, our experiments will provide an ideal basis for the search for the physiological mechanisms of magnetic field perception.

Hand placement near the visual stimulus improves orientation selectivity in V2 neurons

PubMed Central

Sergio, Lauren E.; Crawford, J. Douglas; Fallah, Mazyar

2015-01-01

Often, the brain receives more sensory input than it can process simultaneously. Spatial attention helps overcome this limitation by preferentially processing input from a behaviorally-relevant location. Recent neuropsychological and psychophysical studies suggest that attention is deployed to near-hand space much like how the oculomotor system can deploy attention to an upcoming gaze position. Here we provide the first neuronal evidence that the presence of a nearby hand enhances orientation selectivity in early visual processing area V2. When the hand was placed outside the receptive field, responses to the preferred orientation were significantly enhanced without a corresponding significant increase at the orthogonal orientation. Consequently, there was also a significant sharpening of orientation tuning. In addition, the presence of the hand reduced neuronal response variability. These results indicate that attention is automatically deployed to the space around a hand, improving orientation selectivity. Importantly, this appears to be optimal for motor control of the hand, as opposed to oculomotor mechanisms which enhance responses without sharpening orientation selectivity. Effector-based mechanisms for visual enhancement thus support not only the spatiotemporal dissociation of gaze and reach, but also the optimization of vision for their separate requirements for guiding movements. PMID:25717165

Electrically controlled magnetic circular dichroism and Faraday rotation in graphene

NASA Astrophysics Data System (ADS)

Kuzmenko, Alexey; Poumirol, Jean-Marie; Liu, Peter Q. Liu; Slipchenko, Tetiana; Nikitin, Alexey; Martin-Moreno, Luis; Faist, Jerome

Magnetic circular dichroism (MCD) and Faraday rotation (FR) are the fundamental phenomena of great practical importance arising from the breaking of the time reversal symmetry by a magnetic field. In most materials the strength and the sign of these effects can be only controlled by the field value and its orientation. Using broadband terahertz magneto-electro-optical spectroscopy, we demonstrate that in graphene both the MCD and the FR can be modulated in intensity, tuned in frequency and, importantly, inverted using only electrostatic doping at a fixed magnetic field due to the unique properties of the Dirac fermions. Our results indicate the fundamental possibility of compact, efficient, electrically invertible and wavelength-tunable non-reciprocal passive terahertz elements based on graphene operating at ambient temperature.

Seasonal and clonal variation in cellulose microfibril orientation during cell wall formation of tracheids in Cryptomeria japonica.

PubMed

Jyske, Tuula; Fujiwara, Takeshi; Kuroda, Katsushi; Iki, Taiichi; Zhang, Chunhua; Jyske, Tuomas K; Abe, Hisashi

2014-08-01

To investigate the biological mechanism by which trees control the changes in microfibril (MF) orientation among secondary cell wall layers of conifer tracheids, we studied seasonal variation in the orientation of newly deposited MFs during tracheid cell wall development in Japanese cedar (Cryptomeria japonica D. Don) trees growing in Central Japan (36°36'N, 140°39'E). Sample blocks were repeatedly collected from four 16-year-old clones of different origins during the growing season of 2010 to investigate the hypotheses that changes in cellulose MF orientation between wall layers exhibited seasonal and clonal differences. The progressive change in the orientation of newly deposited MFs on the primary and secondary cell wall layers of tracheids was detected by field-emission-scanning electron microscopy. Tracheid production and differentiation was studied by light microscopy. We observed a decreasing trend in the orientation of deposited MFs from earlywood to latewood in the S2 and S1 layers, where MFs appeared in a Z-helix. In contrast, no seasonal pattern in the orientation of the MFs in the S-helix was observed. Minor clonal variation was observed in the phenology of tracheid production and differentiation. We concluded that a seasonal decreasing trend in the orientation of the MFs in the Z-helix in S1 and S2 was present, whereas the MFs in other layers exhibited minor random variations. Thus, the orientation of the MFs in S2 was affected by seasonal factors, whereas the MFs in other layers were more intrinsically controlled. The within-ring variations in the MF orientation and thus the resulting average MF angle might also be related to genotypic differences in the tracheid production and differentiation rate. However, our results do not exclude other intrinsic and environmental regulations in the change in MF orientation, which remains a topic for future studies. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

In-plane orientation and composition dependences of crystal structure and electrical properties of {100}-oriented Pb(Zr,Ti)O3 films grown on (100) Si substrates by metal organic chemical vapor deposition

NASA Astrophysics Data System (ADS)

Okamoto, Shoji; Sankara Rama Krishnan, P. S.; Okamoto, Satoshi; Yokoyama, Shintaro; Akiyama, Kensuke; Funakubo, Hiroshi

2017-10-01

In-plane orientation-controlled Pb(Zr x ,Ti1- x )O3 (PZT) films with a thickness of approximately 2 µm and a Zr/(Zr + Ti) ratio of 0.39-0.65 were grown on (100) Si substrates by pulsed metal-organic chemical vapor deposition (MOCVD). In-plane-oriented epitaxial PZT films and in-plane random fiber-textured PZT films with {100} out-of-plane orientation were grown on (100)c SrRuO3//(100)c LaNiO3//(100) CeO2//(100) YSZ//(100) Si and (100)c SrRuO3/(100)c LaNiO3/(111) Pt/TiO2/SiO2/(100) Si substrates, respectively. The effects of Zr/(Zr + Ti) ratio and in-plane orientation on the crystal structure, dielectric, ferroelectric, and piezoelectric properties of the films were systematically investigated. The X-ray diffraction measurement showed that the epitaxial PZT films had a higher volume fraction of (100) orientation than the fiber-textured PZT films in the tetragonal Zr/(Zr + Ti) ratio region. A large difference was not detected between the epitaxial films and the fiber-textured films for Zr/(Zr + Ti) ratio dependence of the dielectric constant, and remanent polarization. However, in the rhombohedral phase region [Zr/(Zr + Ti) = 0.65], coercive field was found to be 1.5-fold different between the epitaxial and fiber-textured PZT films. The maximum field-induced strains measured at 0-100 kV/cm by scanning atomic force microscopy were obtained at approximately Zr/(Zr + Ti) = 0.50 and were about 0.5 and 0.3% for the epitaxial and fiber-textured PZT films, respectively.

A field test of electromagnetic geophysical techniques for locating simulated in situ mining leach solution

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

Tweeton, D.R.; Hanson, J.C.; Friedel, M.J.

1994-01-01

The US Bureau of Mines, The University of Arizona, Sandia National Laboratories, and Zonge Engineering and Research Organization, Inc., conducted cooperative field tests of six electromagnetic (EM) geophysical methods to compare their effectiveness in locating a brine solution simulating in situ leach solution or a high-conductivity plume of contamination. The brine was approximately 160 m below the surface. The testsite was the University's San Xavier experimental mine near Tucson, AZ. Geophysical surveys using surface and surface-borehole, time-domain electromagnetic (TEM) induction; surface controlled-source audiofrequency magnetotellurics (CSAMT); surface-borehole, frequency-domain electromagnetic (FEM) induction; crosshole FEM; and surface magnetic field ellipticity were conducted beforemore » and during brine injection. The surface TEM data showed a broad decrease in resistivity. CSAMT measurements with the conventional orientation did not detect the brine, but measurements with another orientation indicated some decrease in resistivity. The surface-borehole and crosshole methods located a known fracture and other fracture zones inferred from borehole induction logs. Surface magnetic field ellipticity data showed a broad decrease in resistivity at depth following brine injection.« less

Future orientation and health quality of life in primary care: vitality as a mediator.

PubMed

Hirsch, Jameson K; Molnar, Danielle; Chang, Edward C; Sirois, Fuschia M

2015-07-01

Temporal perspective, including views about future goals, may influence motivational processes related to health. An adaptive sense of future orientation is linked to better health, but little research has examined potential underlying factors, such as vitality. In a sample of 101 primary care patients, we examined whether belief in the changeability of the future was related to mental and physical energization and, in turn, to health-related quality of life. Participants were working, uninsured primary care patients, who completed self-report measures of future orientation, vitality, and health-related quality of life. Mediation models, covarying age, sex, and race/ethnicity indicated that vitality significantly mediated the association between future orientation and the outcomes of general health, mental health, social functioning, bodily pain, and role limitations due to emotional and physical reasons. Vitality exerted an indirect-only effect on the relation between future orientation and physical functioning. Our findings suggest that adaptive beliefs about the future may promote, or allow access to, physical and mental energy and, in turn, may result in better mental and physical health functioning. Individual-level and public health interventions designed to promote future orientation and vitality may beneficially influence quality of life and well-being.

A Flywheel Energy Storage System Demonstration for Space Applications

NASA Technical Reports Server (NTRS)

Kenny, Barbara H.; Kascak, Peter E.; Jansen, Ralph; Dever, Timothy

2003-01-01

A novel control algorithm for the charge and discharge modes of operation of a flywheel energy storage system for space applications is presented. The motor control portion of the algorithm uses sensorless field oriented control with position and speed estimates determined from a signal injection technique at low speeds and a back EMF technique at higher speeds. The charge and discharge portion of the algorithm use command feed-forward and disturbance decoupling, respectively, to achieve fast response with low gains. Simulation and experimental results are presented.

Development of Next-Generation Borehole Magnetometer and Its Potential Application in Constraining the Magnetic Declination of Oman Samail Ophiolite at ICDP Drill Sites

NASA Astrophysics Data System (ADS)

Lee, S. M.; Parq, J. H.; Kim, H.; Moe, K.; Lee, C. S.; Kanamatsu, T.; Kim, K. J.; Bahk, K. S.

2017-12-01

Determining the azimuthal orientation of core samples obtained from deep drilling is extremely difficult because the core itself could have rotated during drilling operations. Several indirect methods have been devised to address this issue, but have certain limitations. Thus it is still a challenge to determine the azimuthal orientation consistently over the entire length of the hole. Provided that the recovery rate is high and thus all the other magnetic properties such as magnetization intensity and inclination are measured from the recovered cores, one possible method for ascertaining magnetic declination information is to measure the magnetic field inside the empty borehole and invert for the best fitting declination. However, there are two major problems: one is that present-day borehole magnetometers are not precise enough to resolve changes in direction of magnetization, and the other is that in most rock drilling experiments the rate of recovery is low. To overcome the first major problem which is technical, scientists from Korea and Japan jointly conducted the development for the next-generation borehole magnetometer, namely 3GBM (3rd Generation Borehole Magnetometer). The borehole magnetometer which uses fiber-optic laser gyro promises to provide accurate information on not only the magnetic field itself but also the orientation of the instrument inside the borehole. Our goal is to deploy this borehole magnetometer in the ICDP Oman Drilling Project Phase 2 drilling experiment early 2018. The site may be suitable for the investigation because, as recent Phase 1 of the Oman Samail Ophiolite drilling has demonstrated, the recovery rate was very high. Also the post-drilling measurements onboard DV Chikyu have shown that much of the recovered samples has moderate magnetization intensity on the order of 0.1 and 1 A/m. Here, we present the results of numerical simulation of magnetic field inside the borehole using finite element method to show that magnetic declination may be obtained systematically from the top to the bottom of the holes. The results will help us to fine tune the magnetometer before the actual deployment. It will also be useful in interpreting the obtained results together with resistivity images from conventional wireline logging and post-drilling paleomagnetic lab measurements results.

Localized Dictionaries Based Orientation Field Estimation for Latent Fingerprints.

PubMed

Xiao Yang; Jianjiang Feng; Jie Zhou

2014-05-01

Dictionary based orientation field estimation approach has shown promising performance for latent fingerprints. In this paper, we seek to exploit stronger prior knowledge of fingerprints in order to further improve the performance. Realizing that ridge orientations at different locations of fingerprints have different characteristics, we propose a localized dictionaries-based orientation field estimation algorithm, in which noisy orientation patch at a location output by a local estimation approach is replaced by real orientation patch in the local dictionary at the same location. The precondition of applying localized dictionaries is that the pose of the latent fingerprint needs to be estimated. We propose a Hough transform-based fingerprint pose estimation algorithm, in which the predictions about fingerprint pose made by all orientation patches in the latent fingerprint are accumulated. Experimental results on challenging latent fingerprint datasets show the proposed method outperforms previous ones markedly.

Application of Volatile Antifungal Plant Essential Oils for Controlling Pepper Fruit Anthracnose by Colletotrichum gloeosporioides

PubMed Central

Hong, Jeum Kyu; Yang, Hye Ji; Jung, Heesoo; Yoon, Dong June; Sang, Mee Kyung; Jeun, Yong-Chull

2015-01-01

Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for eco-friendly disease management of anthracnose during pepper fruit production. PMID:26361475

Modeling the effect of neighboring grains on twin growth in HCP polycrystals

DOE PAGES

Kumar, M. Arul; Beyerlein, I. J.; Lebensohn, R. A.; ...

2017-08-04

In this paper, we study the dependence of neighboring grain orientation on the local stress state around a deformation twin in a hexagonal close packed (HCP) crystal and its effects on the resistance against twin thickening. We use a recently developed, full-field elasto-visco-plastic formulation based on fast Fourier transforms that accounts for the twinning shear transformation imposed by the twin lamella. The study is applied to Mg, Zr and Ti, since these HCP metals tend to deform by activation of different types of slip modes. The analysis shows that the local stress along the twin boundary are strongly controlled bymore » the relative orientation of the easiest deformation modes in the neighboring grain with respect to the twin lamella in the parent grain. A geometric expression that captures this parent-neighbor relationship is proposed and incorporated into a larger scale, mean-field visco-plastic self-consistent model to simulate the role of neighboring grain orientation on twin thickening. We demonstrate that the approach improves the prediction of twin area fraction distribution when compared with experimental observations.« less

Controlling the orientation of spin-correlated radical pairs by covalent linkage to nanoporous anodic aluminum oxide membranes.

PubMed

Chen, Hsiao-Fan; Gardner, Daniel M; Carmieli, Raanan; Wasielewski, Michael R

2013-10-07

Ordered multi-spin assemblies are required for developing solid-state molecule-based spintronics. A linear donor-chromophore-acceptor (D-C-A) molecule was covalently attached inside the 150 nm diam. nanopores of an anodic aluminum oxide (AAO) membrane. Photoexcitation of D-C-A in a 343 mT magnetic field results in sub-nanosecond, two-step electron transfer to yield the spin-correlated radical ion pair (SCRP) (1)(D(+)˙-C-A(-)˙), which then undergoes radical pair intersystem crossing (RP-ISC) to yield (3)(D(+)˙-C-A(-)˙). RP-ISC results in S-T0 mixing to selectively populate the coherent superposition states |S'> and |T'>. Microwave-induced transitions between these states and the unpopulated |T(+1)> and |T(-1)> states result in spin-polarized time-resolved EPR (TREPR) spectra. The dependence of the electron spin polarization (ESP) phase of the TREPR spectra on the orientation of the AAO membrane pores relative to the externally applied magnetic field is used to determine the overall orientation of the SCRPs within the pores at room temperature.

Modeling the effect of neighboring grains on twin growth in HCP polycrystals

NASA Astrophysics Data System (ADS)

Kumar, M. Arul; Beyerlein, I. J.; Lebensohn, R. A.; Tomé, C. N.

2017-09-01

In this paper, we study the dependence of neighboring grain orientation on the local stress state around a deformation twin in a hexagonal close packed (HCP) crystal and its effects on the resistance against twin thickening. We use a recently developed, full-field elasto-visco-plastic formulation based on fast Fourier transforms that account for the twinning shear transformation imposed by the twin lamella. The study is applied to Mg, Zr and Ti, since these HCP metals tend to deform by activation of different types of slip modes. The analysis shows that the local stress along the twin boundary are strongly controlled by the relative orientation of the easiest deformation modes in the neighboring grain with respect to the twin lamella in the parent grain. A geometric expression that captures this parent-neighbor relationship is proposed and incorporated into a larger scale, mean-field visco-plastic self-consistent model to simulate the role of neighboring grain orientation on twin thickening. We demonstrate that the approach improves the prediction of twin area fraction distribution when compared with experimental observations.

Powering up with indirect reciprocity in a large-scale field experiment

PubMed Central

Yoeli, Erez; Hoffman, Moshe; Rand, David G.; Nowak, Martin A.

2013-01-01

A defining aspect of human cooperation is the use of sophisticated indirect reciprocity. We observe others, talk about others, and act accordingly. We help those who help others, and we cooperate expecting that others will cooperate in return. Indirect reciprocity is based on reputation, which spreads by communication. A crucial aspect of indirect reciprocity is observability: reputation effects can support cooperation as long as peoples’ actions can be observed by others. In evolutionary models of indirect reciprocity, natural selection favors cooperation when observability is sufficiently high. Complimenting this theoretical work are experiments where observability promotes cooperation among small groups playing games in the laboratory. Until now, however, there has been little evidence of observability’s power to promote large-scale cooperation in real world settings. Here we provide such evidence using a field study involving 2413 subjects. We collaborated with a utility company to study participation in a program designed to prevent blackouts. We show that observability triples participation in this public goods game. The effect is over four times larger than offering a $25 monetary incentive, the company’s previous policy. Furthermore, as predicted by indirect reciprocity, we provide evidence that reputational concerns are driving our observability effect. In sum, we show how indirect reciprocity can be harnessed to increase cooperation in a relevant, real-world public goods game. PMID:23754399

Tactile orientation perception: an ideal observer analysis of human psychophysical performance in relation to macaque area 3b receptive fields

PubMed Central

Peters, Ryan M.; Staibano, Phillip

2015-01-01

The ability to resolve the orientation of edges is crucial to daily tactile and sensorimotor function, yet the means by which edge perception occurs is not well understood. Primate cortical area 3b neurons have diverse receptive field (RF) spatial structures that may participate in edge orientation perception. We evaluated five candidate RF models for macaque area 3b neurons, previously recorded while an oriented bar contacted the monkey's fingertip. We used a Bayesian classifier to assign each neuron a best-fit RF structure. We generated predictions for human performance by implementing an ideal observer that optimally decoded stimulus-evoked spike counts in the model neurons. The ideal observer predicted a saturating reduction in bar orientation discrimination threshold with increasing bar length. We tested 24 humans on an automated, precision-controlled bar orientation discrimination task and observed performance consistent with that predicted. We next queried the ideal observer to discover the RF structure and number of cortical neurons that best matched each participant's performance. Human perception was matched with a median of 24 model neurons firing throughout a 1-s period. The 10 lowest-performing participants were fit with RFs lacking inhibitory sidebands, whereas 12 of the 14 higher-performing participants were fit with RFs containing inhibitory sidebands. Participants whose discrimination improved as bar length increased to 10 mm were fit with longer RFs; those who performed well on the 2-mm bar, with narrower RFs. These results suggest plausible RF features and computational strategies underlying tactile spatial perception and may have implications for perceptual learning. PMID:26354318

Translational models of infection prevention and control: lessons from studying high risk aging populations.

PubMed

Mody, Lona

2018-06-13

The present review describes our research experiences and efforts in advancing the field of infection prevention and control in nursing facilities including postacute and long-term care settings. There are over two million infections in postacute and long-term care settings each year in the United States and $4 billion in associated costs. To define a target group most amenable to infection prevention and control interventions, we sought to quantify the relation between indwelling device use and microbial colonization in nursing facility patients. Using various methodologies including survey methods, observational epidemiology, randomized controlled studies, and collaboratives, we showed that indwelling device type is related to the site of multidrug-resistant organism (MDRO) colonization; multianatomic site colonization with MDROs is common; community-associated methicillin-resistant Staphylococcus aureus (MRSA) appeared in the nursing facility setting almost immediately following its emergence in acute care; (4) MDRO prevalence and catheter-associated infection rates can be reduced through a multimodal targeted infection prevention intervention; and (5) using a collaborative approach, such an intervention can be successfully scaled up. Our work advances the infection prevention field through translational research utilizing various methodologies, including quantitative and qualitative surveys, patient-oriented randomized controlled trials, and clinical microbiologic and molecular methods. The resulting interventions employ patient-oriented methods to reduce infections and antimicrobial resistance, and with partnerships from major national entities, can be implemented nationally.

Familial transmission of a body-related attentional bias - An eye-tracking study in a nonclinical sample of female adolescents and their mothers.

PubMed

Bauer, Anika; Schneider, Silvia; Waldorf, Manuel; Adolph, Dirk; Vocks, Silja

2017-01-01

Previous research indicates that body image disturbance is transmitted from mother to daughter via modeling of maternal body-related behaviors and attitudes (indirect transmission) and via maternal body-related feedback (direct transmission). So far, the transmission of body-related attentional biases, which according to cognitive-behavioral theories play a prominent role in the development and maintenance of eating disorders, has not been analyzed. The current eye-tracking study applied the concepts of direct and indirect transmission to body-related attentional biases by examining body-related viewing patterns on self- and other-pictures within mother-daughter dyads. Eye movements of N = 82 participants (n = 41 healthy female adolescents, mean age 15.82 years, SD = 1.80, and their mothers, mean age 47.78 years, SD = 4.52) were recorded while looking at whole-body pictures of themselves and a control peer. Based on fixations on self-defined attractive and unattractive body areas, visual attention bias scores were calculated for mothers and daughters, representing the pattern of body-related attention allocation. Based on mothers' fixations on their own daughter's and the adolescent peer's body, a second visual attention bias score was calculated, reflecting the mothers' viewing pattern on their own daughter. Analysis of variance revealed an attentional bias for self-defined unattractive body areas in adolescents. The girls' visual attention bias score correlated significantly with their mothers' bias score, indicating indirect transmission, and with their mothers' second bias score, indicating direct transmission. Moreover, the girls' bias score correlated significantly with negative body-related feedback from their mothers. Female adolescents show a deficit-oriented attentional bias for one's own and a peer's body. The correlated body-related attention patterns imply that attentional biases might be transmitted directly and indirectly from mothers to daughters. Results underline the potential relevance of maternal influences for the development of body image disturbance in girls and suggest specific family-based approaches for the prevention and treatment of eating disorders.

Weak Broadband Electromagnetic Fields are More Disruptive to Magnetic Compass Orientation in a Night-Migratory Songbird (Erithacus rubecula) than Strong Narrow-Band Fields

PubMed Central

Schwarze, Susanne; Schneider, Nils-Lasse; Reichl, Thomas; Dreyer, David; Lefeldt, Nele; Engels, Svenja; Baker, Neville; Hore, P. J.; Mouritsen, Henrik

2016-01-01

Magnetic compass orientation in night-migratory songbirds is embedded in the visual system and seems to be based on a light-dependent radical pair mechanism. Recent findings suggest that both broadband electromagnetic fields ranging from ~2 kHz to ~9 MHz and narrow-band fields at the so-called Larmor frequency for a free electron in the Earth’s magnetic field can disrupt this mechanism. However, due to local magnetic fields generated by nuclear spins, effects specific to the Larmor frequency are difficult to understand considering that the primary sensory molecule should be organic and probably a protein. We therefore constructed a purpose-built laboratory and tested the orientation capabilities of European robins in an electromagnetically silent environment, under the specific influence of four different oscillating narrow-band electromagnetic fields, at the Larmor frequency, double the Larmor frequency, 1.315 MHz or 50 Hz, and in the presence of broadband electromagnetic noise covering the range from ~2 kHz to ~9 MHz. Our results indicated that the magnetic compass orientation of European robins could not be disrupted by any of the relatively strong narrow-band electromagnetic fields employed here, but that the weak broadband field very efficiently disrupted their orientation. PMID:27047356

Antituberculosis nanodelivery system with controlled-release properties based on para-amino salicylate–zinc aluminum-layered double-hydroxide nanocomposites

PubMed Central

Saifullah, Bullo; Hussein, Mohd Zobir; Hussein-Al-Ali, Samer Hasan; Arulselvan, Palanisamy; Fakurazi, Sharida

2013-01-01

We report the intercalation and characterization of para-amino salicylic acid (PASA) into zinc/aluminum-layered double hydroxides (ZLDHs) by two methods, direct and indirect, to form nanocomposites: PASA nanocomposite prepared by a direct method (PASA-D) and PASA nanocomposite prepared by an indirect method (PASA-I). Powder X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis revealed that the PASA drugs were accommodated within the ZLDH interlayers. The anions of the drug were accommodated as an alternate monolayer (along the long-axis orientation) between ZLDH interlayers. Drug loading was estimated to be 22.8% and 16.6% for PASA-D and PASA-I, respectively. The in vitro release properties of the drug were investigated in physiological simulated phosphate-buffered saline solution of pH 7.4 and 4.8. The release followed the pseudo-second-order model for both nanocomposites. Cell viability (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide [MTT] assays) was assessed against normal human lung fibroblast MRC-5 and 3T3 mouse fibroblast cells at 24, 48, and 72 hours. The results showed that the nanocomposite formulations did not possess any cytotoxicity, at least up to 72 hours. PMID:24255593

Envisioning an America Without Sexual Orientation Inequities in Adolescent Health

PubMed Central

Birkett, Michelle; Greene, George J.; Hatzenbuehler, Mark L.; Newcomb, Michael E.

2014-01-01

This article explicates a vision for social change throughout multiple levels of society necessary to eliminate sexual orientation health disparities in youths. We utilized the framework of Bronfenbrenner’s ecological theory of development, a multisystemic model of development that considers direct and indirect influences of multiple levels of the environment. Within this multisystem model we discuss societal and political influences, educational systems, neighborhoods and communities, romantic relationships, families, and individuals. We stress that continued change toward equity in the treatment of lesbian, gay, and bisexual youths across these levels will break down the barriers for these youths to achieve healthy development on par with their heterosexual peers. PMID:24328618

How racial/ethnic bullying affects rejection sensitivity: the role of social dominance orientation.

PubMed

Wu, Ivan H C; Lyons, Brent; Leong, Frederick T L

2015-01-01

The authors built upon models of workplace bullying to examine how racial/ethnic bullying can lead to racial/ethnic minorities' sensitivity to future discrimination via its effects on race/ethnic-related stress. With a sample of racial/ethnic minorities, they found support for this process. Individual differences in social dominance orientation (SDO) also attenuated the mediation: The indirect effect of race/ethnic-related stress was weaker for minorities who endorse hierarchy legitimizing ideologies (high in SDO) compared to minorities low in SDO. Practical implications for the management of minority employees' experiences of discrimination are discussed. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Direct and indirect measurement of physical activity in older adults: a systematic review of the literature

PubMed Central

2012-01-01

Background Due to physiological and cognitive changes that occur with aging, accurate physical activity (PA) measurement in older adults represents a unique challenge. The primary purpose of this study was to systematically review measures of PA and their use and appropriateness with older adults. A secondary aim was to determine the level of agreement between PA measures in older adults. Methods Literature was identified through electronic databases. Studies were eligible if they examined the correlation and/or agreement between at least 2 measures, either indirect and/or direct, of PA in older adults (> 65 years of age). Results Thirty-six studies met eligibility criteria. The indirect and direct measures of PA across the studies differed widely in their ability to address the key dimensions (i.e., frequency, intensity, time, type) of PA in older adults. The average correlation between indirect and direct measures was moderate (r=0.38). The correlation between indirect and other indirect measures (r=0.29) was weak, while correlations between direct measures with other direct measures were high (real world: r= 0.84; controlled settings: r=0.92). Agreement was strongest between direct PA measures with other direct measures in both real world and laboratory settings. While a clear trend regarding the agreement for mean differences between other PA measures (i.e., direct with indirect, indirect with indirect) did not emerge, there were only a limited number of studies that reported comparable units. Conclusions Despite the lack of a clear trend regarding the agreement between PA measures in older adults, the findings underscore the importance of valid, accurate and reliable measurement. To advance this field, researchers will need to approach the assessment of PA in older adults in a more standardized way (i.e., consistent reporting of results, consensus over cut-points and epoch lengths, using appropriate validation tools). Until then researchers should be cautious when choosing measures for PA that are appropriate for their research questions and when comparing PA levels across various studies. PMID:23245612

Magnetic effect on dancing bees

NASA Technical Reports Server (NTRS)

Lindauer, M.; Martin, H.

1972-01-01

Bee sensitivity to the earth's magnetic field is studied. Data cover sensitivity range and the use of magnetoreception for orientation purposes. Experimental results indicate bee orientation is aided by gravity fields when the magnetic field is compensated.

Magnetosensitive neurons mediate geomagnetic orientation in Caenorhabditis elegans

PubMed Central

Vidal-Gadea, Andrés; Ward, Kristi; Beron, Celia; Ghorashian, Navid; Gokce, Sertan; Russell, Joshua; Truong, Nicholas; Parikh, Adhishri; Gadea, Otilia; Ben-Yakar, Adela; Pierce-Shimomura, Jonathan

2015-01-01

Many organisms spanning from bacteria to mammals orient to the earth's magnetic field. For a few animals, central neurons responsive to earth-strength magnetic fields have been identified; however, magnetosensory neurons have yet to be identified in any animal. We show that the nematode Caenorhabditis elegans orients to the earth's magnetic field during vertical burrowing migrations. Well-fed worms migrated up, while starved worms migrated down. Populations isolated from around the world, migrated at angles to the magnetic vector that would optimize vertical translation in their native soil, with northern- and southern-hemisphere worms displaying opposite migratory preferences. Magnetic orientation and vertical migrations required the TAX-4 cyclic nucleotide-gated ion channel in the AFD sensory neuron pair. Calcium imaging showed that these neurons respond to magnetic fields even without synaptic input. C. elegans may have adapted magnetic orientation to simplify their vertical burrowing migration by reducing the orientation task from three dimensions to one. DOI: http://dx.doi.org/10.7554/eLife.07493.001 PMID:26083711

ALLTEM Multi-Axis Electromagnetic Induction System Demonstration and Validation

DTIC Science & Technology

2011-11-17

fencing that test the capabilities of the platform systems Recently the Open Field area was reconfigured to emulate typical impact area conditions. The...surveyed. • Open field (indirect fire) The indirect fire subarea contains only three munition types that could be typically found at an impact area...direct fire subarea contains only three munition types that could be typically found at an impact area of a direct fire weapons range. These are 25 mm

General field and office procedures for indirect discharge measurements

USGS Publications Warehouse

Benson, M.A.; Dalrymple, Tate

2001-04-01

The discharge of streams is usually measured by the current-meter method. During flood periods, however, it is frequently impossible or impractical to measure the discharges by this method when they occur. Consequently, many peak discharges must be determined after the passage of the flood by indirect methods, such as slope-area, contracted-opening, flow-over-dam, and flow-through-culvert, rather than by direct current-meter measurement. Indirect methods of determining peak discharge are based on hydraulic equations which relate the discharge to the water-surface profile and the geometry of the channel. A field survey is made after the flood to determine the location and elevation of high-water marks and the characteristics of the channel. Detailed descriptions of the general procedures used in collecting the field data and in computing the discharge are given in this report. Each of the methods requires special procedures described in subsequent chapters.

Navy-ASEE (American Society for Engineering Education) Summer Faculty Research Program for 1982 with a Cummulative Compilation of Data on Later Research Fallouts from the 1979 and 1980 and 1981 Programs.

DTIC Science & Technology

1982-01-01

Oriental or Asian groups and 5 were non - minority women. Of the 24 minority representatives 9 were Black, 14 were of Oriental or Asian backgrounds and one... controlled atmospheres. Reactions of carbon dioxide with metal complexes are relatively rare, and John Cooper and his group at Naval Research...of the NSFRP parti- * cipants in 1982 held the Ph.D. or an quivalent doctoral degree in their field of expertise and approximately one third were

Interplanetary magnetic field orientation for transient events in the outer magnetosphere

NASA Technical Reports Server (NTRS)

Sibeck, D. G.; Newell, P. T.

1995-01-01

It is generally believed that flux transfer events (FTEs) in the outer dayside magneosphere, usually identified by transient (approximately 1 min) bipolar magneitc field perturbations in the direction normal to the nominal magnetopause, occur when the magnetosheath magetic field has a southward component. We compare the results of three methods for determining the magnetosheath magnetic field orientationat the times of previously identified UKS/IRM events: (1) the average magnetosheath magnetic field orientation in the 30-min period adjacent to the nearest magnetopause crossing, (2) the magnetosheath magnetic field orientation observed just outside the magnetopause, and (3) the lagged interplanetary magnetic field (IMF) orientation at the time of the transient events. Whereas the results of method 2 indicate that the events tend to occur for a southward magnetosheath magnetic field, the results of methods 1 and 3 show no such tnedency. The fact that the three methods yield significantly diffeent results emphasizes the need for caution in future studies.

A Computational Study of How Orientation Bias in the Lateral Geniculate Nucleus Can Give Rise to Orientation Selectivity in Primary Visual Cortex

PubMed Central

Kuhlmann, Levin; Vidyasagar, Trichur R.

2011-01-01

Controversy remains about how orientation selectivity emerges in simple cells of the mammalian primary visual cortex. In this paper, we present a computational model of how the orientation-biased responses of cells in lateral geniculate nucleus (LGN) can contribute to the orientation selectivity in simple cells in cats. We propose that simple cells are excited by lateral geniculate fields with an orientation-bias and disynaptically inhibited by unoriented lateral geniculate fields (or biased fields pooled across orientations), both at approximately the same retinotopic co-ordinates. This interaction, combined with recurrent cortical excitation and inhibition, helps to create the sharp orientation tuning seen in simple cell responses. Along with describing orientation selectivity, the model also accounts for the spatial frequency and length–response functions in simple cells, in normal conditions as well as under the influence of the GABAA antagonist, bicuculline. In addition, the model captures the response properties of LGN and simple cells to simultaneous visual stimulation and electrical stimulation of the LGN. We show that the sharp selectivity for stimulus orientation seen in primary visual cortical cells can be achieved without the excitatory convergence of the LGN input cells with receptive fields along a line in visual space, which has been a core assumption in classical models of visual cortex. We have also simulated how the full range of orientations seen in the cortex can emerge from the activity among broadly tuned channels tuned to a limited number of optimum orientations, just as in the classical case of coding for color in trichromatic primates. PMID:22013414

Formation of (111) orientation-controlled ferroelectric orthorhombic HfO{sub 2} thin films from solid phase via annealing

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

Mimura, Takanori; Katayama, Kiliha; Shimizu, Takao

2016-08-01

0.07YO{sub 1.5}-0.93HfO{sub 2} (YHO7) films were prepared on various substrates by pulse laser deposition at room temperature and subsequent heat treatment to enable a solid phase reaction. (111)-oriented 10 wt. % Sn-doped In{sub 2}O{sub 3}(ITO)//(111) yttria-stabilized zirconia, (111)Pt/TiO{sub x}/SiO{sub 2}/(001)Si substrates, and (111)ITO/(111)Pt/TiO{sub x}/SiO{sub 2}/(001)Si substrates were employed for film growth. In this study, X-ray diffraction measurements including θ–2θ measurements, reciprocal space mappings, and pole figure measurements were used to study the films. The film on (111)ITO//(111)yttria-stabilized zirconia was an (111)-orientated epitaxial film with ferroelectric orthorhombic phase; the film on (111)ITO/(111)Pt/TiO{sub x}/SiO{sub 2}/(001)Si was an (111)-oriented uniaxial textured film with ferroelectricmore » orthorhombic phase; and no preferred orientation was observed for the film on the (111)Pt/TiO{sub x}/SiO{sub 2}/(001)Si substrate, which does not contain ITO. Polarization–hysteresis measurements confirmed that the films on ITO covered substrates had saturated ferroelectric hysteresis loops. A remanent polarization (P{sub r}) of 9.6 and 10.8 μC/cm{sup 2} and coercive fields (E{sub c}) of 1.9 and 2.0 MV/cm were obtained for the (111)-oriented epitaxial and uniaxial textured YHO7 films, respectively. These results demonstrate that the (111)-oriented ITO bottom electrodes play a key role in controlling the orientation and ferroelectricity of the phase formation of the solid films deposited at room temperature.« less

Rigorous theory of molecular orientational nonlinear optics

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

Kwak, Chong Hoon, E-mail: chkwak@ynu.ac.kr; Kim, Gun Yeup

2015-01-15

Classical statistical mechanics of the molecular optics theory proposed by Buckingham [A. D. Buckingham and J. A. Pople, Proc. Phys. Soc. A 68, 905 (1955)] has been extended to describe the field induced molecular orientational polarization effects on nonlinear optics. In this paper, we present the generalized molecular orientational nonlinear optical processes (MONLO) through the calculation of the classical orientational averaging using the Boltzmann type time-averaged orientational interaction energy in the randomly oriented molecular system under the influence of applied electric fields. The focal points of the calculation are (1) the derivation of rigorous tensorial components of the effective molecularmore » hyperpolarizabilities, (2) the molecular orientational polarizations and the electronic polarizations including the well-known third-order dc polarization, dc electric field induced Kerr effect (dc Kerr effect), optical Kerr effect (OKE), dc electric field induced second harmonic generation (EFISH), degenerate four wave mixing (DFWM) and third harmonic generation (THG). We also present some of the new predictive MONLO processes. For second-order MONLO, second-order optical rectification (SOR), Pockels effect and difference frequency generation (DFG) are described in terms of the anisotropic coefficients of first hyperpolarizability. And, for third-order MONLO, third-order optical rectification (TOR), dc electric field induced difference frequency generation (EFIDFG) and pump-probe transmission are presented.« less

Study on signal intensity of low field nuclear magnetic resonance via an indirect coupling measurement

NASA Astrophysics Data System (ADS)

Jiang, Feng-Ying; Wang, Ning; Jin, Yi-Rong; Deng, Hui; Tian, Ye; Lang, Pei-Lin; Li, Jie; Chen, Ying-Fei; Zheng, Dong-Ning

2013-04-01

We carry out an ultra-low-field nuclear magnetic resonance (NMR) experiment based on high-Tc superconducting quantum interference devices (SQUIDs). The measurement field is in a micro-tesla range (~10 μT-100 μT) and the experiment is conducted in a home-made magnetically-shielded-room (MSR). The measurements are performed by the indirect coupling method in which the signal of nuclei precession is indirectly coupled to the SQUID through a tuned copper coil transformer. In such an arrangement, the interferences of applied measurement and polarization field to the SQUID sensor are avoided and the performance of the SQUID is not destroyed. In order to compare the detection sensitivity obtained by using the SQUID with that achieved using a conventional low-noise-amplifier, we perform the measurements using a commercial room temperature amplifier. The results show that in a wide frequency range (~1 kHz-10 kHz) the measurements with the SQUID sensor exhibit a higher signal-to-noise ratio. Further, we discuss the dependence of NMR peak magnitude on measurement frequency. We attribute the reduction of the peak magnitude at high frequency to the increased field inhomogeneity as the measurement field increases. This is verified by compensating the field gradient using three sets of gradient coils.

The Control of Auxin Transport in Parasitic and Symbiotic Root–Microbe Interactions

PubMed Central

Ng, Jason Liang Pin; Perrine-Walker, Francine; Wasson, Anton P.; Mathesius, Ulrike

2015-01-01

Most field-grown plants are surrounded by microbes, especially from the soil. Some of these, including bacteria, fungi and nematodes, specifically manipulate the growth and development of their plant hosts, primarily for the formation of structures housing the microbes in roots. These developmental processes require the correct localization of the phytohormone auxin, which is involved in the control of cell division, cell enlargement, organ development and defense, and is thus a likely target for microbes that infect and invade plants. Some microbes have the ability to directly synthesize auxin. Others produce specific signals that indirectly alter the accumulation of auxin in the plant by altering auxin transport. This review highlights root–microbe interactions in which auxin transport is known to be targeted by symbionts and parasites to manipulate the development of their host root system. We include case studies for parasitic root–nematode interactions, mycorrhizal symbioses as well as nitrogen fixing symbioses in actinorhizal and legume hosts. The mechanisms to achieve auxin transport control that have been studied in model organisms include the induction of plant flavonoids that indirectly alter auxin transport and the direct targeting of auxin transporters by nematode effectors. In most cases, detailed mechanisms of auxin transport control remain unknown. PMID:27135343

Supply side management innovation: —Analysis on Enterprises in Scientific Industry Park Based on Market Orientation

NASA Astrophysics Data System (ADS)

Li, Xing; Mao, Fenlan; Lin, Mian; Yadi, Nan

2017-12-01

This research presents a conceptual framework for incorporating organizational learning and innovations as the mediating variables between market orientation and organizational performance. The samples of this study include 145 companies from the information technology industry in the Scientific Industry Parks. The global model fit is acceptable. This empirical result supports the constructs mentioned above. 1. Market orientation has a positive and direct impact on organizational learning, administrative and technical innovation. 2. Organizational learning has a positive and direct impact on administrative and technical innovation, but with no statistically significant direct impact on performance. 3. Organizational learning does have a positive and indirect impact on performance by means of organizational innovations. 4. It is not statistically significant that the impact of the two innovation types (both administrative and technical) interact with each other.

Does self-efficacy mediate functional change in older adults participating in an exercise program after hip fracture? A randomized controlled trial.

PubMed

Chang, Feng-Hang; Latham, Nancy K; Ni, Pengsheng; Jette, Alan M

2015-06-01

To examine whether self-efficacy mediated the effect of the Home-based Post-Hip Fracture Rehabilitation program on activity limitations in older adults after hip fracture and whether the mediating effect was different between sex and age groups. Randomized controlled trial. Community. Participants with hip fracture (N=232; mean age ± SD, 79±9.4y) were randomly assigned to intervention (n=120, 51.7%) and attention control (n=112, 48.3%) groups. The 6-month intervention, the Home-based Post-Hip Fracture Rehabilitation, is a functionally oriented, home-based exercise program. Data were collected at baseline, postintervention (6mo), and follow-up (9mo). Activity Measure for Post-Acute Care. The mediating effect of the Home-based Post-Hip Fracture Rehabilitation program on Basic Mobility function through self-efficacy for exercise was significant at 9 months (βindirect=.21). Similarly, the mediating effect of the intervention on Daily Activity function through self-efficacy for exercise was significant at 9 months (βindirect=.49). In subgroup analyses, the mediating effect was significant at 9 months in the younger group (age, ≤79y) in comparison to the older group and was significant in women in comparison to men. Self-efficacy may play a partial mediating role in the effect on some longer-term functional outcomes in the Home-based Post-Hip Fracture Rehabilitation intervention. The results suggest that program components that target self-efficacy should be incorporated in future hip fracture rehabilitation interventions. Age and sex of the targeted participants may also need to be considered when developing interventions. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Does self-efficacy mediate functional change in older adults participating in an exercise program after hip fracture? A randomized control trial

PubMed Central

Latham, Nancy K.; Ni, Pengsheng; Jette, Alan M.

2015-01-01

Objectives This study examined whether self-efficacy mediated the effect of the HIP Rehab exercise program on activity limitations in older adults after hip fracture, and whether the mediation effect was different between different gender and age groups. Design Randomized controlled trial (RCT) Setting Community Participants Two hundred and thirty two participants aged 79±9.4 years with hip fracture were randomly assigned to intervention (n=120) or attention control (n=112) groups. Interventions The 6-month intervention, the HIP Rehab, is a functionally-oriented, home-based exercise program. Data was collected at baseline, post-intervention (6 months), and follow-up (9 months). Main outcome measure Activity Measure for Post-Acute Care (AM-PAC) Results The mediation effect of the HIP Rehab exercise program on Basic Mobility function through self-efficacy for exercise was significant at 9 months (βindirect=0.21). Similarly, the mediation effect of the intervention on Daily Activity function through self-efficacy for exercise was significant at 9 months (βindirect=0.49). In subgroup analyses, the mediation effect was significant at 9 months in the younger group (≤79 years old) in comparison to the older group, and was significant in females in comparison to males. Conclusion Self-efficacy may play a partial mediating role for the effect on some longer-term functional outcomes in the HIP Rehab intervention. The results suggest that program components that target self-efficacy should be incorporated in the future hip fracture rehabilitation interventions. Age and gender of the targeted participants may also need to be considered when developing interventions. PMID:25701101

Driven assembly with multiaxial fields: Creating a soft mode in assemblies of anisometric induced dipoles

DOE PAGES

Martin, James E.; Swol, Frank Van

2015-07-10

We show that multiaxial fields can induce time-averaged, noncentrosymmetric interactions between particles having polarization anisotropy, yet the multiaxial field itself does not exert either a force or a torque on an isolated particle. These induced interactions lead to particle assemblies whose energy is strongly dependent on both the translational and orientational degrees of freedom of the system. The situation is similar to a collection of permanent dipoles, but the symmetry of the time-averaged interaction is quite distinct, and the scale of the system energy can be dynamically controlled by the magnitude of the applied multiaxial field. In our paper, themore » case of polarizable rods is considered in detail, and it is suggested that collections of rods embedded in spheres can be used to create a material with a dynamically tunable magnetic permeability or dielectric permittivity. We report on Monte Carlo simulations performed to investigate the behavior of assemblies of both multiaxial-field induced dipoles and permanent dipoles arranged onto two-dimensional lattices. Lastly, the ground state of the induced dipoles is an orientational soft mode of aligned dipoles, whereas that of the permanent dipoles is a vortex state.« less

In situ study of electric field controlled ion transport in the Fe/BaTiO3 interface

NASA Astrophysics Data System (ADS)

Merkel, D. G.; Bessas, D.; Bazsó, G.; Jafari, A.; Rüffer, R.; Chumakov, A. I.; Khanh, N. Q.; Sajti, Sz; Celse, J.-P.; Nagy, D. L.

2018-01-01

Electric field controlled ion transport and interface formation of iron thin films on a BaTiO3 substrate have been investigated by in situ nuclear resonance scattering and x-ray reflectometry techniques. At early stage of deposition, an iron-II oxide interface layer was observed. The hyperfine parameters of the interface layer were found insensitive to the evaporated layer thickness. When an electric field was applied during growth, a 10 Å increase of the nonmagnetic/magnetic thickness threshold and an extended magnetic transition region was measured compared to the case where no field was applied. The interface layer was found stable under this threshold when further evaporation occurred, contrary to the magnetic layer where the magnitude and orientation of the hyperfine magnetic field vary continuously. The obtained results of the growth mechanism and of the electric field effect of the Fe/BTO system will allow the design of novel applications by creating custom oxide/metallic nanopatterns using laterally inhomogeneous electric fields during sample preparation.

The Impact of Agentic and Communal Exercise Messages on Individuals' Exercise Class Attitudes, Self-Efficacy Beliefs, and Intention to Attend.

PubMed

Howle, Timothy C; Dimmock, James A; Ntoumanis, Nikos; Chatzisarantis, Nikos L D; Sparks, Cassandra; Jackson, Ben

2017-12-01

We tested the effects of advertisements about a fictitious exercise class-derived using the theoretical constructs of agency and communion-on recipients' perceptions about, and interest in, the class. The final sample consisted of 150 adults (M age  = 44.69, SD = 15.83). Results revealed that participants who received a communal-oriented message reported significantly greater exercise task self-efficacy and more positive affective attitudes relative to those who received an agentic-oriented message. Communal (relative to agentic) messages were also indirectly responsible for greater intentions to attend the class, via more positive self-efficacy beliefs and affective attitudes. These findings were obtained despite the use of another manipulation to orient participants to either agency or communion goals. The results indicate that the primacy of communion over agency for message recipients may extend to exercise settings and may occur irrespective of whether participants are situationally oriented toward agency or communion.

Applicability of New Approaches of Sensor Orientation to Micro Aerial Vehicles

NASA Astrophysics Data System (ADS)

Rehak, M.; Skaloud, J.

2016-06-01

This study highlights the benefits of precise aerial position and attitude control in the context of mapping with Micro Aerial Vehicles (MAVs). Accurate mapping with MAVs is gaining importance in applications such as corridor mapping, road and pipeline inspections or mapping of large areas with homogeneous surface structure, e.g. forests or agricultural fields. There, accurate aerial control plays a major role in successful terrain reconstruction and artifact-free ortophoto generation. The presented experiments focus on new approaches of aerial control. We confirm practically that the relative aerial position and attitude control can improve accuracy in difficult mapping scenarios. Indeed, the relative orientation method represents an attractive alternative in the context of MAVs for two reasons. First, the procedure is somewhat simplified, e.g. the angular misalignment, so called boresight, between the camera and the inertial measurement unit (IMU) does not have to be determined and, second, the effect of possible systematic errors in satellite positioning (e.g. due to multipath and/or incorrect recovery of differential carrier-phase ambiguities) is mitigated. First, we present a typical mapping project over an agricultural field and second, we perform a corridor road mapping. We evaluate the proposed methods in scenarios with and without automated image observations. We investigate a recently proposed concept where adjustment is performed using image observations limited to ground control and check points, so called fast aerial triangulation (Fast AT). In this context we show that accurate aerial control (absolute or relative) together with a few image observations can deliver accurate results comparable to classical aerial triangulation with thousands of image measurements. This procedure in turns reduces the demands on processing time and the requirements on the existence of surface texture. Finally, we compare the above mentioned procedures with direct sensor orientation (DiSO) to show its potential for rapid mapping.

Multimaterial magnetically assisted 3D printing of composite materials.

PubMed

Kokkinis, Dimitri; Schaffner, Manuel; Studart, André R

2015-10-23

3D printing has become commonplace for the manufacturing of objects with unusual geometries. Recent developments that enabled printing of multiple materials indicate that the technology can potentially offer a much wider design space beyond unusual shaping. Here we show that a new dimension in this design space can be exploited through the control of the orientation of anisotropic particles used as building blocks during a direct ink-writing process. Particle orientation control is demonstrated by applying low magnetic fields on deposited inks pre-loaded with magnetized stiff platelets. Multimaterial dispensers and a two-component mixing unit provide additional control over the local composition of the printed material. The five-dimensional design space covered by the proposed multimaterial magnetically assisted 3D printing platform (MM-3D printing) opens the way towards the manufacturing of functional heterogeneous materials with exquisite microstructural features thus far only accessible by biological materials grown in nature.

Controls on Early-Rift Geometry: New Perspectives From the Bilila-Mtakataka Fault, Malawi

NASA Astrophysics Data System (ADS)

Hodge, M.; Fagereng, Å.; Biggs, J.; Mdala, H.

2018-05-01

We use the ˜110-km long Bilila-Mtakataka fault in the amagmatic southern East African Rift, Malawi, to investigate the controls on early-rift geometry at the scale of a major border fault. Morphological variations along the 14 ± 8-m high scarp define six 10- to 40-km long segments, which are either foliation parallel or oblique to both foliation and the current regional extension direction. As the scarp is neither consistently parallel to foliation nor well oriented for the current regional extension direction, we suggest that the segmented surface expression is related to the local reactivation of well-oriented weak shallow fabrics above a broadly continuous structure at depth. Using a geometrical model, the geometry of the best fitting subsurface structure is consistent with the local strain field from recent seismicity. In conclusion, within this early-rift, preexisting weaknesses only locally control border fault geometry at subsurface.

Multimaterial magnetically assisted 3D printing of composite materials

NASA Astrophysics Data System (ADS)

Kokkinis, Dimitri; Schaffner, Manuel; Studart, André R.

2015-10-01

3D printing has become commonplace for the manufacturing of objects with unusual geometries. Recent developments that enabled printing of multiple materials indicate that the technology can potentially offer a much wider design space beyond unusual shaping. Here we show that a new dimension in this design space can be exploited through the control of the orientation of anisotropic particles used as building blocks during a direct ink-writing process. Particle orientation control is demonstrated by applying low magnetic fields on deposited inks pre-loaded with magnetized stiff platelets. Multimaterial dispensers and a two-component mixing unit provide additional control over the local composition of the printed material. The five-dimensional design space covered by the proposed multimaterial magnetically assisted 3D printing platform (MM-3D printing) opens the way towards the manufacturing of functional heterogeneous materials with exquisite microstructural features thus far only accessible by biological materials grown in nature.

Measuring Filament Orientation: A New Quantitative, Local Approach

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

Green, C.-E.; Cunningham, M. R.; Jones, P. A.

The relative orientation between filamentary structures in molecular clouds and the ambient magnetic field provides insight into filament formation and stability. To calculate the relative orientation, a measurement of filament orientation is first required. We propose a new method to calculate the orientation of the one-pixel-wide filament skeleton that is output by filament identification algorithms such as filfinder. We derive the local filament orientation from the direction of the intensity gradient in the skeleton image using the Sobel filter and a few simple post-processing steps. We call this the “Sobel-gradient method.” The resulting filament orientation map can be compared quantitativelymore » on a local scale with the magnetic field orientation map to then find the relative orientation of the filament with respect to the magnetic field at each point along the filament. It can also be used for constructing radial profiles for filament width fitting. The proposed method facilitates automation in analyses of filament skeletons, which is imperative in this era of “big data.”.« less

Demonstration for Social Change: An Experiment in Local Control.

ERIC Educational Resources Information Center

Gittell, Marilyn; And Others

This evaluative history of New York City's recent experiments in public education documents three projects: Ocean Hill-Brownsville, IS 201, and Two Bridges. This study employs a process oriented and a qualitative methodology which relies most on field observation and participant-observers. The Institute study observed the new community boards,…

Control of enzymatic browning in potato (Solanum tuberosum L.) by sense and antisense RNA from tomato polyphenol oxidase.

PubMed

Coetzer, C; Corsini, D; Love, S; Pavek, J; Tumer, N

2001-02-01

Polyphenol oxidase (PPO) activity of Russet Burbank potato was inhibited by sense and antisense PPO RNAs expressed from a tomato PPO cDNA under the control of the 35S promoter from the cauliflower mosaic virus. Transgenic Russet Burbank potato plants from 37 different lines were grown in the field. PPO activity and the level of enzymatic browning were measured in the tubers harvested from the field. Of the tubers from 28 transgenic lines that were sampled, tubers from 5 lines exhibited reduced browning. The level of PPO activity correlated with the reduction in enzymatic browning in these lines. These results indicate that expression of tomato PPO RNA in sense or antisense orientation inhibits PPO activity and enzymatic browning in the major commercial potato cultivar. Expression of tomato PPO RNA in sense orientation led to the greatest decrease in PPO activity and enzymatic browning, possibly due to cosuppression. These results suggest that expression of closely related heterologous genes can be used to prevent enzymatic browning in a wide variety of food crops without the application of various food additives.

Alignment of SWNTs by protein-ligand interaction of functionalized magnetic particles under low magnetic fields.

PubMed

Park, Tae Jung; Park, Jong Pil; Lee, Seok Jae; Jung, Dae-Hwan; Ko, Young Koan; Jung, Hee-Tae; Lee, Sang Yup

2011-05-01

Carbon nanotubes (CNTs) have attracted considerable attention for applications using their superior mechanical, thermal and electrical properties. A simple method to controllably align single-walled CNTs (SWNTs) by using magnetic particles embedded with superparamagnetic iron oxide as an accelerator under the magnetic field was developed. The functionalization of SWNTs using biotin, interacted with streptavidin-coupled magnetic particles (micro-to-nano in diameter), and layer-by-layer assembly were performed for the alignment of a particular direction onto the clean silicon and the gold substrate at very low magnetic forces (0.02-0.89 T) at room temperature. The successful alignment of the SWNTs with multi-layer film was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). By changing the orientation and location of the substrates, crossed-networks of SWNTs-magnetic particle complex could easily be fabricated. We suggest that this approach, which consists of a combination of biological interaction among streptavidin-biotin and magnetite particles, should be useful for lateral orientation of individual SWNTs with controllable direction.

Effects of Field and Job Oriented Technical Retraining on Manpower Utilization of the Unemployed. Vocational-Industrial Education Research Report. Final Report.

ERIC Educational Resources Information Center

Bjorkquist, David C.

A job-oriented program emphasizing application to the specific occupation of tool design was compared with a field-oriented program intended to give a broad basic preparation for a variety of jobs in the field of mechanical technology. Both programs were conducted under the Manpower Development and Training Act (MDTA) for a period of 52 weeks.…

Infrared vibrational nanocrystallography and nanoimaging

PubMed Central

Muller, Eric A.; Pollard, Benjamin; Bechtel, Hans A.; van Blerkom, Peter; Raschke, Markus B.

2016-01-01

Molecular solids and polymers can form low-symmetry crystal structures that exhibit anisotropic electron and ion mobility in engineered devices or biological systems. The distribution of molecular orientation and disorder then controls the macroscopic material response, yet it is difficult to image with conventional techniques on the nanoscale. We demonstrated a new form of optical nanocrystallography that combines scattering-type scanning near-field optical microscopy with both optical antenna and tip-selective infrared vibrational spectroscopy. From the symmetry-selective probing of molecular bond orientation with nanometer spatial resolution, we determined crystalline phases and orientation in aggregates and films of the organic electronic material perylenetetracarboxylic dianhydride. Mapping disorder within and between individual nanoscale domains, the correlative hybrid imaging of nanoscale heterogeneity provides insight into defect formation and propagation during growth in functional molecular solids. PMID:27730212

Experimental and theoretical NMR and IR studies of the side-chain orientation effects on the backbone conformation of dehydrophenylalanine residue.

PubMed

Buczek, Aneta M; Ptak, Tomasz; Kupka, Teobald; Broda, Małgorzata A

2011-06-01

Conformation of N-acetyl-(E)-dehydrophenylalanine N', N'-dimethylamide (Ac-(E)-ΔPhe-NMe(2)) in solution, a member of (E)-α, β-dehydroamino acids, was studied by NMR and infrared spectroscopy and the results were compared with those obtained for (Z) isomer. To support the spectroscopic interpretation, the Φ, Ψ potential energy surfaces were calculated at the MP2/6-31 + G(d,p) level of theory in chloroform solution modeled by the self-consistent reaction field-polarizable continuum model method. All minima were fully optimized by the MP2 method and their relative stabilities were analyzed in terms of π-conjugation, internal H-bonds and dipole interactions between carbonyl groups. The obtained NMR spectral features were compared with theoretical nuclear magnetic shieldings, calculated using Gauge Independent Atomic Orbitals (GIAO) approach and rescaled to theoretical chemical shifts using benzene as reference. The calculated indirect nuclear spin-spin coupling constants were compared with available experimental parameters. Copyright © 2011 John Wiley & Sons, Ltd.

Reducing Stereotype Threat With Embodied Triggers: A Case of Sensorimotor-Mental Congruence.

PubMed

Chalabaev, Aïna; Radel, Rémi; Masicampo, E J; Dru, Vincent

2016-08-01

In four experiments, we tested whether embodied triggers may reduce stereotype threat. We predicted that left-side sensorimotor inductions would increase cognitive performance under stereotype threat, because such inductions are linked to avoidance motivation among right-handers. This sensorimotor-mental congruence hypothesis rests on regulatory fit research showing that stereotype threat may be reduced by avoidance-oriented interventions, and motor congruence research showing positive effects when two parameters of a motor action activate the same motivational system (avoidance or approach). Results indicated that under stereotype threat, cognitive performance was higher when participants contracted their left hand (Study 1) or when the stimuli were presented on the left side of the visual field (Studies 2-4), as compared with right-hand contraction or right-side visual stimulation. These results were observed on math (Studies 1, 2, and 4) and Stroop (Study 3) performance. An indirect effect of congruence on math performance through subjective fluency was also observed. © 2016 by the Society for Personality and Social Psychology, Inc.

On the representation and estimation of spatial uncertainty. [for mobile robot

NASA Technical Reports Server (NTRS)

Smith, Randall C.; Cheeseman, Peter

1987-01-01

This paper describes a general method for estimating the nominal relationship and expected error (covariance) between coordinate frames representing the relative locations of objects. The frames may be known only indirectly through a series of spatial relationships, each with its associated error, arising from diverse causes, including positioning errors, measurement errors, or tolerances in part dimensions. This estimation method can be used to answer such questions as whether a camera attached to a robot is likely to have a particular reference object in its field of view. The calculated estimates agree well with those from an independent Monte Carlo simulation. The method makes it possible to decide in advance whether an uncertain relationship is known accurately enough for some task and, if not, how much of an improvement in locational knowledge a proposed sensor will provide. The method presented can be generalized to six degrees of freedom and provides a practical means of estimating the relationships (position and orientation) among objects, as well as estimating the uncertainty associated with the relationships.

Visualizing heavy fermion confinement and Pauli-limited superconductivity in layered CeCoIn 5

DOE PAGES

Gyenis, András; Feldman, Benjamin E.; Randeria, Mallika T.; ...

2018-02-07

Layered material structures play a key role in enhancing electron–electron interactions to create correlated metallic phases that can transform into unconventional superconducting states. The quasi-two-dimensional electronic properties of such compounds are often inferred indirectly through examination of bulk properties. Here we use scanning tunneling microscopy to directly probe in cross-section the quasi-two-dimensional electronic states of the heavy fermion superconductor CeCoIn 5. Our measurements reveal the strong confined nature of quasiparticles, anisotropy of tunneling characteristics, and layer-by-layer modulated behavior of the precursor pseudogap gap phase. In the interlayer coupled superconducting state, the orientation of line defects relative to the d-wave ordermore » parameter determines whether in-gap states form due to scattering. Spectroscopic imaging of the anisotropic magnetic vortex cores directly characterizes the short interlayer superconducting coherence length and shows an electronic phase separation near the upper critical in-plane magnetic field, consistent with a Pauli-limited first-order phase transition into a pseudogap phase.« less

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

Gyenis, András; Feldman, Benjamin E.; Randeria, Mallika T.

Layered material structures play a key role in enhancing electron–electron interactions to create correlated metallic phases that can transform into unconventional superconducting states. The quasi-two-dimensional electronic properties of such compounds are often inferred indirectly through examination of bulk properties. Here we use scanning tunneling microscopy to directly probe in cross-section the quasi-two-dimensional electronic states of the heavy fermion superconductor CeCoIn 5. Our measurements reveal the strong confined nature of quasiparticles, anisotropy of tunneling characteristics, and layer-by-layer modulated behavior of the precursor pseudogap gap phase. In the interlayer coupled superconducting state, the orientation of line defects relative to the d-wave ordermore » parameter determines whether in-gap states form due to scattering. Spectroscopic imaging of the anisotropic magnetic vortex cores directly characterizes the short interlayer superconducting coherence length and shows an electronic phase separation near the upper critical in-plane magnetic field, consistent with a Pauli-limited first-order phase transition into a pseudogap phase.« less

Mesoscopic monodisperse ferromagnetic colloids enable magnetically controlled photonic crystals.

PubMed

Xu, Xiangling; Majetich, Sara A; Asher, Sanford A

2002-11-20

We report here the first synthesis of mesoscopic, monodisperse particles which contain nanoscopic inclusions of ferromagnetic cobalt ferrites. These monodisperse ferromagnetic composite particles readily self-assemble into magnetically responsive photonic crystals that efficiently Bragg diffract incident light. Magnetic fields can be used to control the photonic crystal orientation and, thus, the diffracted wavelength. We demonstrate the use of these ferromagnetic particles to fabricate magneto-optical diffracting fluids and magnetically switchable diffracting mirrors.

Novel Organic Field Effect Transistors via Nano-Modification

DTIC Science & Technology

2005-07-01

mobility by using two kinds of nano-scale films. One is to apply the photoalignment method on a nano-scale film to control the orientation of pentacene ...scale film (polymer electrolyte) to control moving of ions in/out an active semiconducor, pentacene or conducting polymer, for improving carrier...mobility. In this project, pentacene or a series of conducting polymers, such as the derivatives of PANI and P3HT will be patterned and manufactured in

Accuracy assessment of high resolution satellite imagery orientation by leave-one-out method

NASA Astrophysics Data System (ADS)

Brovelli, Maria Antonia; Crespi, Mattia; Fratarcangeli, Francesca; Giannone, Francesca; Realini, Eugenio

Interest in high-resolution satellite imagery (HRSI) is spreading in several application fields, at both scientific and commercial levels. Fundamental and critical goals for the geometric use of this kind of imagery are their orientation and orthorectification, processes able to georeference the imagery and correct the geometric deformations they undergo during acquisition. In order to exploit the actual potentialities of orthorectified imagery in Geomatics applications, the definition of a methodology to assess the spatial accuracy achievable from oriented imagery is a crucial topic. In this paper we want to propose a new method for accuracy assessment based on the Leave-One-Out Cross-Validation (LOOCV), a model validation method already applied in different fields such as machine learning, bioinformatics and generally in any other field requiring an evaluation of the performance of a learning algorithm (e.g. in geostatistics), but never applied to HRSI orientation accuracy assessment. The proposed method exhibits interesting features which are able to overcome the most remarkable drawbacks involved by the commonly used method (Hold-Out Validation — HOV), based on the partitioning of the known ground points in two sets: the first is used in the orientation-orthorectification model (GCPs — Ground Control Points) and the second is used to validate the model itself (CPs — Check Points). In fact the HOV is generally not reliable and it is not applicable when a low number of ground points is available. To test the proposed method we implemented a new routine that performs the LOOCV in the software SISAR, developed by the Geodesy and Geomatics Team at the Sapienza University of Rome to perform the rigorous orientation of HRSI; this routine was tested on some EROS-A and QuickBird images. Moreover, these images were also oriented using the world recognized commercial software OrthoEngine v. 10 (included in the Geomatica suite by PCI), manually performing the LOOCV since only the HOV is implemented. The software comparison guaranteed about the overall correctness and good performances of the SISAR model, whereas the results showed the good features of the LOOCV method.

Steering a virtual blowfly: simulation of visual pursuit.

PubMed

Boeddeker, Norbert; Egelhaaf, Martin

2003-09-22

The behavioural repertoire of male flies includes visually guided chasing after moving targets. The visuomotor control system for these pursuits belongs to the fastest found in the animal kingdom. We simulated a virtual fly, to test whether or not experimentally established hypotheses on the underlying control system are sufficient to explain chasing behaviour. Two operating instructions for steering the chasing virtual fly were derived from behavioural experiments: (i) the retinal size of the target controls the fly's forward speed and, thus, indirectly its distance to the target; and (ii) a smooth pursuit system uses the retinal position of the target to regulate the fly's flight direction. Low-pass filters implement neuronal processing time. Treating the virtual fly as a point mass, its kinematics are modelled in consideration of the effects of translatory inertia and air friction. Despite its simplicity, the model shows behaviour similar to that of real flies. Depending on its starting position and orientation as well as on target size and speed, the virtual fly either catches the target or follows it indefinitely without capture. These two behavioural modes of the virtual fly emerge from the control system for flight steering without implementation of an explicit decision maker.

Present-day stress field of Southeast Asia

NASA Astrophysics Data System (ADS)

Tingay, Mark; Morley, Chris; King, Rosalind; Hillis, Richard; Coblentz, David; Hall, Robert

2010-02-01

It is now well established that ridge push forces provide a major control on the plate-scale stress field in most of the Earth's tectonic plates. However, the Sunda plate that comprises much of Southeast Asia is one of only two plates not bounded by a major spreading centre and thus provides an opportunity to evaluate other forces that control the intraplate stress field. The Cenozoic tectonic evolution of the Sunda plate is usually considered to be controlled by escape tectonics associated with India-Eurasia collision. However, the Sunda plate is bounded by a poorly understood and complex range of convergent and strike-slip zones and little is known about the effect of these other plate boundaries on the intraplate stress field in the region. We compile the first extensive stress dataset for Southeast Asia, containing 275 A-D quality (177 A-C) horizontal stress orientations, consisting of 72 stress indicators from earthquakes (located mostly on the periphery of the plate), 202 stress indicators from breakouts and drilling-induced fractures and one hydraulic fracture test within 14 provinces in the plate interior. This data reveals that a variable stress pattern exists throughout Southeast Asia that is largely inconsistent with the Sunda plate's approximately ESE absolute motion direction. The present-day maximum horizontal stress in Thailand, Vietnam and the Malay Basin is predominately north-south, consistent with the radiating stress patterns arising from the eastern Himalayan syntaxis. However, the present-day maximum horizontal stress is primarily oriented NW-SE in Borneo, a direction that may reflect plate-boundary forces or topographic stresses exerted by the central Borneo highlands. Furthermore, the South and Central Sumatra Basins exhibit a NE-SW maximum horizontal stress direction that is perpendicular to the Indo-Australian subduction front. Hence, the plate-scale stress field in Southeast Asia appears to be controlled by a combination of Himalayan orogeny-related deformation, forces related to subduction (primarily trench suction and collision) and intraplate sources of stress such as topography and basin geometry.

Balancing Control and Complexity in Field Studies of Neonicotinoids and Honey Bee Health

PubMed Central

Suryanarayanan, Sainath

2013-01-01

Amidst ongoing declines in honey bee health, the contributory role of the newer systemic insecticides continues to be intensely debated. Scores of toxicological field experiments, which bee scientists and regulators in the United States have looked to for definitive causal evidence, indicate a lack of support. This paper analyzes the methodological norms that shape the design and interpretation of field toxicological studies. I argue that contemporary field studies of honey bees and pesticides are underpinned by a “control-oriented” approach, which precludes a serious investigation of the indirect and multifactorial ways in which pesticides could drive declines in honey bee health. I trace the historical rise to prominence of this approach in honey bee toxicology to the development of entomology as a science of insecticide development in the United States. Drawing on “complexity-oriented” knowledge practices in ecology, epidemiology, beekeeping and sociology, I suggest an alternative socio-ecological systems approach, which would entail in situ studies that are less concerned with isolating individual factors and more attentive to the interactive and place-based mix of factors affecting honey bee health. PMID:26466800

Disorder in the Disk: The Influence of Accretion Disk Thickness on the Large-scale Magnetic Dynamo.

NASA Astrophysics Data System (ADS)

Hogg, J. Drew; Reynolds, Christopher S.

2018-01-01

The evolution of the magnetic field from the enigmatic large-scale dynamo is often considered a central feature of the accretion disk around a black hole. The resulting low-frequency oscillations introduced from the growth and decay of the field strength, along with the change in field orientation, are thought to be intimately tied to variability from the disk. Several factors are at play, but the dynamo can either be directly tied to observable signatures through modulation of the heating rate, or indirectly as the source of quasiperiodic oscillations, the driver of nonlinear structure from propagating fluctuations in mass accretion rate, or even the trigger of state transitions. We present a selection of results from a recent study of this process using a suite of four global, high-resolution, MHD accretion disk simulations. We systematically vary the scale height ratio and find the large-scale dynamo fails to develop above a scale height ratio of h/r ≥ 0.2. Using “butterfly” diagrams of the azimuthal magnetic field, we show the large-scale dynamo exists in the thinner accretion disk models, but fails to excite when the scale height ratio is increased, a feature which is also reflected in 2D Fourier transforms. Additionally, we calculate the dynamo α-parameter through correlations in the averaged magnetic field and turbulent electromotive force, and also generate synthetic light curves from the disk cooling. Using our emission proxy, we find the disks have markedly different characters as photometric fluctuations are larger and less ordered when the disk is thicker and the dynamo is absent.

Orientation behavior of predaceous ground beetle species in response to volatile emissions from yellow starthistle damaged by an invasive slug

USDA-ARS?s Scientific Manuscript database

The up-regulation or emission of plant volatiles in response to herbivory may signal to the natural predators and parasitoids that a plant is under attack from herbivores. This is known as an indirect defense within a tritrophic system - where herbivore number is reduced through predation that is st...

Can native annual forbs reduce Bromus tectorum biomass and indirectly facilitate establishment of a native perennial grass?

Treesearch

Elizabeth A. Leger; Erin M. Goergen; Tara Forbis de Queiroz

2014-01-01

Restoration is challenging in systems invaded by competitive, disturbance oriented plants, but greater success may be achieved by mimicking natural successional processes and including disturbanceoriented natives in a seed mix. We asked whether seven native annual forbs from the Great Basin Desert, USA, were capable of reducing biomass of the invasive annual grass...

Learners' perceptions of learners regarded as having a homosexual orientation in an independent secondary school environment.

PubMed

Mostert, Hendrik P; Myburgh, Chris; Poggenpoel, Marie

2012-10-04

In schools today discrimination based on sexual orientation takes place on a regular basis. This form of discrimination leads to aggression towards learners perceived to be homosexual, as well as towards those with a homosexual orientation. For more than 15 years South Africa has been a democratic country with laws that protect learners who have a homosexual orientation. Nevertheless, aggression and discrimination towards these learners still occur in schools. Aggression often leads to verbal and physical bullying of the victims by perpetrators. The objectives of this research were to explore and describe Grade 11 learners' experiences of aggression towards learners perceived to be homosexual as well as those with a homosexual orientation in an independent secondary school environment. The research design was qualitative, exploratory, descriptive and contextual in nature. The data for this investigation consisted of essays based on a published newspaper photograph, phenomenological group interviews, observations and field notes. Tesch's method of data analysis was used, and an independent coder assisted. Three themes were identified, discussed and supported by a literature control: that learners experience that it is right and acceptable to have a homosexual orientation; that they experience ambivalence towards homosexual orientation of learners; and experienced feelings that it is wrong to have a homosexual orientation. Recommended guidelines are provided to address aggression towards learners perceived to be homosexual and those with a homosexual orientation.

Novel design of highly [110]-oriented barium titanate nanorod array and its application in nanocomposite capacitors.

PubMed

Yao, Lingmin; Pan, Zhongbin; Zhai, Jiwei; Chen, Haydn H D

2017-03-23

Nanocomposites in capacitors combining highly aligned one dimension ferroelectric nanowires with polymer would be more desirable for achieving higher energy density. However, the synthesis of the well-isolated ferroelectric oxide nanorod arrays with a high orientation has been rather scant, especially using glass-made substrates. In this study, a novel design that is capable of fabricating a highly [110]-oriented BaTiO 3 (BT) nanorod array was proposed first, using a three-step hydrothermal reaction on glass-made substrates. The details for controlling the dispersion of the nanorod array, the orientation and the aspect ratio are also discussed. It is found that the alkaline treatment of the TiO 2 (TO) nanorod array, rather than the completing transformation into sodium titanate, favors the transformation of the TO into the BT nanorod array, as well as protecting the glass-made substrate. The dispersity of the nanorod array can be controlled by the introduction of a glycol ether-deionized water mixed solvent and soluble salts. Moreover, the orientation of the nanorod arrays could be tuned by the ionic strength of the solution. This novel BT nanorod array was used as a filler in a nanocomposite capacitor, demonstrating that a large energy density (11.82 J cm -3 ) can be achieved even at a low applied electric field (3200 kV cm -1 ), which opens us a new application in nanocomposite capacitors.

Selective Cooperation in the Supermarket : Field Experimental Evidence for Indirect Reciprocity.

PubMed

Lange, Florian; Eggert, Frank

2015-12-01

Numerous laboratory experiments suggest that mechanisms of indirect reciprocity might account for human cooperation. However, conclusive field data supporting the predictions of indirect reciprocity in everyday life situations is still scarce. Here, we attempt to compensate for this lack by examining the determinants of cooperative behavior in a German supermarket. Our methods were as follows: Confederates of the experimenter lined up at the checkout, apparently to buy a single item. As an act of cooperation, the waiting person in front (the potential helper) could allow the confederate to go ahead. By this means, the potential helper could take a cost (additional waiting time) by providing the confederate with a benefit (saved waiting time). We recorded the potential helpers' behavior and the number of items they purchased as a quantitative measure proportional to the confederate's benefit. Moreover, in a field experimental design, we varied the confederates' image by manipulating the item they purchased (beer vs. water). As predicted, the more waiting time they could save, the more likely the confederates were to receive cooperation. This relationship was moderated by the confederates' image. Cost-to-benefit ratios were required to be more favorable for beer-purchasing individuals to receive cooperation. Our results demonstrate that everyday human cooperation can be studied unobtrusively in the field and that cooperation among strangers is selective in a way that is consistent with current models of indirect reciprocity.

Spatially and time resolved kinetics of indirect magnetoexcitons

NASA Astrophysics Data System (ADS)

Hasling, Matthew; Dorow, Chelsey; Calman, Erica; Butov, Leonid; Wilkes, Joe; Campman, Kenneth; Gossard, Arthur

The small exciton mass and binding energy give the opportunity to realize the high magnetic field regime for excitons in magnetic fields of few Tesla achievable in lab Long lifetimes of indirect exciton give the opportunity to study kinetics of magnetoexciton transport by time-resolved optical imaging of exciton emission. We present spatially and time resolved measurements showing the effect of increased magnetic field on transport of magnetoexcitons. We observe that increased magnetic field leads to slowing down of magnetoexciton transport. Supported by NSF Grant No. 1407277. J.W. was supported by the EPSRC (Grant EP/L022990/1). C.J.D. was supported by the NSF Graduate Research Fellowship Program under Grant No. DGE-1144086.

Motor Control and Regulation for a Flywheel Energy Storage System

NASA Technical Reports Server (NTRS)

Kenny, Barbara; Lyons, Valerie

2003-01-01

This talk will focus on the motor control algorithms used to regulate the flywheel system at the NASA Glenn Research Center. First a discussion of the inner loop torque control technique will be given. It is based on the principle of field orientation and is implemented without a position or speed sensor (sensorless control). Then the outer loop charge and discharge algorithm will be presented. This algorithm controls the acceleration of the flywheel during charging and the deceleration while discharging. The algorithm also allows the flywheel system to regulate the DC bus voltage during the discharge cycle.

'Fixed-axis' magnetic orientation by an amphibian: non-shoreward-directed compass orientation, misdirected homing or positioning a magnetite-based map detector in a consistent alignment relative to the magnetic field?

PubMed

Phillips, John B; Borland, S Chris; Freake, Michael J; Brassart, Jacques; Kirschvink, Joseph L

2002-12-01

Experiments were carried out to investigate the earlier prediction that prolonged exposure to long-wavelength (>500 nm) light would eliminate homing orientation by male Eastern red-spotted newts Notophthalmus viridescens. As in previous experiments, controls held in outdoor tanks under natural lighting conditions and tested in a visually uniform indoor arena under full-spectrum light were homeward oriented. As predicted, however, newts held under long-wavelength light and tested under either full-spectrum or long-wavelength light (>500 nm) failed to show consistent homeward orientation. The newts also did not orient with respect to the shore directions in the outdoor tanks in which they were held prior to testing. Unexpectedly, however, the newts exhibited bimodal orientation along a more-or-less 'fixed' north-northeast-south-southwest magnetic axis. The orientation exhibited by newts tested under full-spectrum light was indistinguishable from that of newts tested under long-wavelength light, although these two wavelength conditions have previously been shown to differentially affect both shoreward compass orientation and homing orientation. To investigate the possibility that the 'fixed-axis' response of the newts was mediated by a magnetoreception mechanism involving single-domain particles of magnetite, natural remanent magnetism (NRM) was measured from a subset of the newts. The distribution of NRM alignments with respect to the head-body axis of the newts was indistinguishable from random. Furthermore, there was no consistent relationship between the NRM of individual newts and their directional response in the overall sample. However, under full-spectrum, but not long-wavelength, light, the alignment of the NRM when the newts reached the 20 cm radius criterion circle in the indoor testing arena (estimated by adding the NRM alignment measured from each newt to its magnetic bearing) was non-randomly distributed. These findings are consistent with the earlier suggestion that homing newts use the light-dependent magnetic compass to align a magnetite-based 'map detector' when obtaining the precise measurements necessary to derive map information from the magnetic field. However, aligning the putative map detector does not explain the fixed-axis response of newts tested under long-wavelength light. Preliminary evidence suggests that, in the absence of reliable directional information from the magnetic compass (caused by the 90 degrees rotation of the response of the magnetic compass under long-wavelength light), newts may resort to a systematic sampling strategy to identify alignment(s) of the map detector that yields reliable magnetic field measurements.

Deception and the Mediterranean Campaigns of 1943-1944

DTIC Science & Technology

1986-03-31

Controlling Section, Radio Deception, Indirect Approach 2a. ABSTRACT (Contifnue m re~.roo & it~aI neceoom7anywd Identify by rdock number) The thesis is...8217Stonewall’ Jackson during the Civil 8Z6 M moo War. Jackson is so important to the study of the history of deception on the battle field that any work...here is the background and events surrounding the planning and execution of deception for the landings in Sicily by the Allies on 10 July 1943. %I 49! m

High microwave attenuation performance of planar carbonyl iron particles with orientation of shape anisotropy field

NASA Astrophysics Data System (ADS)

Guo, Cheng; Yang, Zhihong; Shen, Shile; Liang, Juan; Xu, Guoyue

2018-05-01

Planar anisotropy carbonyl iron (PACI) particles were prepared from commercial spherical carbonyl iron particles through a high performance ball-milling technique. The paraffin composites with orientation of shape anisotropy field for these PACI particles were obtained by applying an external magnetic field during the fabrication process. The frequency-dependent complex permeability values of these prepared paraffin composites have been investigated in the frequency range of 1-18 GHz. The results demonstrate that the orientation of shape anisotropy field for these PACI particles can effectively increase the complex permeability and decrease the complex permittivity values. Benefit from the enhancement in the complex permeability and reduction in the complex permittivity, the better impedance matching condition can be obtained and thus the good microwave absorption performance can be achieved for the samples with enough magnetic field orientation time.

Feasibility study of a layer-oriented wavefront sensor for solar telescopes: comment.

PubMed

Kellerer, Aglaé

2014-11-10

The future generation of telescopes will be equipped with multi-conjugate adaptive-optics (MCAO) systems in order to obtain high angular resolution over large fields of view. MCAO comes in two flavors: star- and layer-oriented. Existing solar MCAO systems rely exclusively on the star-oriented approach. Earlier we suggested a method to implement the layer-oriented approach, and in view of recent concerns by Marino and Wöger [Appl. Opt.53, 685 (2014)10.1364/AO.53.000685APOPAI1559-128X], we now explain the proposed scheme in further detail. We note that in any layer-oriented system one sensor is conjugated to the pupil and the others are conjugated to higher altitudes. For the latter, not all the sensing surface is illuminated by the entire field of view. The successful implementation of nighttime layer-oriented systems shows that the field reduction is no crucial limitation. In the solar approach the field reduction is directly noticeable because it causes vignetting of the Shack-Hartmann subaperture images. It can be accounted for by a suitable adjustment of the algorithms to calculate the local wavefront slopes. We discuss a further concern related to the optical layout of a layer-oriented solar system.

Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

NASA Astrophysics Data System (ADS)

Bonne, François; Alamir, Mazen; Bonnay, Patrick

2014-01-01

In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

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

Bonne, François; Bonnay, Patrick; Alamir, Mazen

2014-01-29

In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection,more » to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.« less

Effects of urbanization on direct and indirect interactions in a tri-trophic system.

PubMed

Tabea, Turrini; Dirk, Sanders; Eva, Knop

2016-04-01

While effects of urbanization on species assemblages are receiving increasing attention, effects on ecological interactions remain largely unexplored. We investigated how urbanization influences the strength of direct and indirect trophic interactions in a tri- trophic system. In a field experiment including five cities and nearby farmed areas, we used potted Vicia faba plants and manipulated the presence of Megoura viciae aphids and that of naturally occurring aphid predators. When predators could access aphids, they reduced their abundance less in the urban than in the agricultural ecosystem. Compared to aphid abundance on plants without predator access, abundance on plants with predator access was 2.58 times lower in urban and 5.27 times lower in agricultural areas. This indicates that urbanization limited top-down control of aphids by predators. In both ecosystems, plant biomass was negatively affected by herbivores and positively affected by predators, but the positive indirect predator effect was weaker in cities. Compared to aphid-infested plants without predator access, plants with predator access were 1.89 times heavier in urban and 2.12 times heavier in agricultural areas. Surprisingly, differences between ecosystems regarding the indirect predator effect on plants were not explained by the differentially strong herbivore suppression. Instead, the urban environment limited plant biomass per se, thereby mitigating the scope of a positive predator effect. Our results show that urbanization can influence direct and indirect trophic interactions through effects on biotic top-down forces and on plant growth. In order to understand how urbanization affects biodiversity and ecosystem functioning, it is fundamental to not only consider species assemblages, but also species interactions.

Bespoke optical springs and passive force clamps from shaped dielectric particles

NASA Astrophysics Data System (ADS)

Simpson, S. H.; Phillips, D. B.; Carberry, D. M.; Hanna, S.

2013-09-01

By moulding optical fields, holographic optical tweezers are able to generate structured force fields with magnitudes and length scales of great utility for experiments in soft matter and biological physics. It has recently been noted that optically induced force fields are determined not only by the incident optical field, but by the shape and composition of the particles involved [Gluckstad J. Optical manipulation: sculpting the object. Nat Photonics 2011;5:7-8]. Indeed, there are desirable but simple attributes of a force field, such as orientational control, that cannot be introduced by sculpting optical fields alone. With this insight in mind, we show, theoretically, how relationships between force and displacement can be controlled by optimizing particle shapes. We exhibit a constant force optical spring, made from a tapered microrod and discuss methods by which it could be fabricated. In addition, we investigate the optical analogue of streamlining, and show how objects can be shaped so as to reduce the effects of radiation pressure, and hence switch from non-trapping to trapping regimes.

Effect of visual field locus and oscillation frequencies on posture control in an ecological environment.

PubMed

Piponnier, Jean-Claude; Hanssens, Jean-Marie; Faubert, Jocelyn

2009-01-14

To examine the respective roles of central and peripheral vision in the control of posture, body sway amplitude (BSA) and postural perturbations (given by velocity root mean square or vRMS) were calculated in a group of 19 healthy young adults. The stimulus was a 3D tunnel, either static or moving sinusoidally in the anterior-posterior direction. There were nine visual field conditions: four central conditions (4, 7, 15, and 30 degrees); four peripheral conditions (central occlusions of 4, 7, 15, and 30 degrees); and a full visual field condition (FF). The virtual tunnel respected all the aspects of a real physical tunnel (i.e., stereoscopy and size increase with proximity). The results show that, under static conditions, central and peripheral visual fields appear to have equal importance for the control of stance. In the presence of an optic flow, peripheral vision plays a crucial role in the control of stance, since it is responsible for a compensatory sway, whereas central vision has an accessory role that seems to be related to spatial orientation.

Perceived Mortality and Perceived Morality: Perceptions of Value-Orientation Are More Likely When a Decision Is Preceded by a Mortality Reminder

PubMed Central

Nordmo, Mads; Norman, Elisabeth

2016-01-01

The questions addressed in this paper are whether and how reported mortality reminders can function as an indication of sincerity when communicating ambiguously motivated decisions. In two experiments, participants were exposed to a fictitious CEO who announced a decision to implement new organizational measures that were both environmentally and financially beneficial. In the experimental condition, the CEO attributed her new ideas to a recent mortality reminder. In the active control condition, the CEO attributed her decision to a non-lethal dentistry health scare, and in the passive control condition the CEO did not give any account of events preceding her decision. When a CEO implemented new corporate initiatives after a mortality reminder, her motivation for doing so was perceived as somewhat more motivated by intrinsic values, and significantly less motivated by financial gains. This change in attribution patterns was demonstrated to be indirectly related to a positive evaluation of the CEO, as well as an increased willingness to pay for the organization’s services. The second experiment further demonstrated that the reduced attribution to financial motivation associated with mortality awareness persisted even when the CEO in question was known for placing a high personal priority on financial goal attainment. The findings underscore the importance of perceived value-oriented motivation when communicating climate change mitigating policies, and the role of mortality awareness as one of many ways to induce such attributions. PMID:26973555

Perceived Mortality and Perceived Morality: Perceptions of Value-Orientation Are More Likely When a Decision Is Preceded by a Mortality Reminder.

PubMed

Nordmo, Mads; Norman, Elisabeth

2016-01-01

The questions addressed in this paper are whether and how reported mortality reminders can function as an indication of sincerity when communicating ambiguously motivated decisions. In two experiments, participants were exposed to a fictitious CEO who announced a decision to implement new organizational measures that were both environmentally and financially beneficial. In the experimental condition, the CEO attributed her new ideas to a recent mortality reminder. In the active control condition, the CEO attributed her decision to a non-lethal dentistry health scare, and in the passive control condition the CEO did not give any account of events preceding her decision. When a CEO implemented new corporate initiatives after a mortality reminder, her motivation for doing so was perceived as somewhat more motivated by intrinsic values, and significantly less motivated by financial gains. This change in attribution patterns was demonstrated to be indirectly related to a positive evaluation of the CEO, as well as an increased willingness to pay for the organization's services. The second experiment further demonstrated that the reduced attribution to financial motivation associated with mortality awareness persisted even when the CEO in question was known for placing a high personal priority on financial goal attainment. The findings underscore the importance of perceived value-oriented motivation when communicating climate change mitigating policies, and the role of mortality awareness as one of many ways to induce such attributions.

High magnetic field processing of liquid crystalline polymers

DOEpatents

Smith, M.E.; Benicewicz, B.C.; Douglas, E.P.

1998-11-24

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

High magnetic field processing of liquid crystalline polymers

DOEpatents

Smith, Mark E.; Benicewicz, Brian C.; Douglas, Elliot P.

1998-01-01

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

Indirect nontarget effects of host-specific biological control agents: Implications for biological control

Treesearch

Dean E. Pearson; Ragan M. Callaway

2005-01-01

Classical biological control of weeds currently operates under the assumption that biological control agents are safe (i.e., low risk) if they do not directly attack nontarget species. However, recent studies indicate that even highly host-specific biological control agents can impact nontarget species through indirect effects. This finding has profound...

Synthesis and Self-Assembly of fcc Phase FePt Nanorods

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

Chen, Min; Pica, Timothy; Jiang, Ying-Bing

2007-05-01

In this paper, we report a synthesis of FePt nanorods by confining decomposition of Fe(CO) 5 and reduction of Pt(caca) 2 in surfactant reverse cylindrical micelles. The controlled nucleation and growth kinetics in confined environment allows easy control over Fe/Pt composition, nanorod uniformity, and nanorod aspect ratio. The FePt nanorods tend to self-assemble into ordered arrays along three-dimensions. Directed assembly under external magnetic field leads to two-dimensional ordered arrays, parallel to the substrate magnetic field. We expect that with optimized external magnetic fields, we should be able to assemble these nanorods into orientated one or two-dimensional arrays, providing a uniformmore » anisotropic magnetic platform for varied applications in enhanced data storage, magneto-electron transport, etc.« less

A linear model fails to predict orientation selectivity of cells in the cat visual cortex.

PubMed Central

Volgushev, M; Vidyasagar, T R; Pei, X

1996-01-01

1. Postsynaptic potentials (PSPs) evoked by visual stimulation in simple cells in the cat visual cortex were recorded using in vivo whole-cell technique. Responses to small spots of light presented at different positions over the receptive field and responses to elongated bars of different orientations centred on the receptive field were recorded. 2. To test whether a linear model can account for orientation selectivity of cortical neurones, responses to elongated bars were compared with responses predicted by a linear model from the receptive field map obtained from flashing spots. 3. The linear model faithfully predicted the preferred orientation, but not the degree of orientation selectivity or the sharpness of orientation tuning. The ratio of optimal to non-optimal responses was always underestimated by the model. 4. Thus non-linear mechanisms, which can include suppression of non-optimal responses and/or amplification of optimal responses, are involved in the generation of orientation selectivity in the primary visual cortex. PMID:8930828

Changes in herbivore control in arable fields by detrital subsidies depend on predator species and vary in space.

PubMed

von Berg, Karsten; Thies, Carsten; Tscharntke, Teja; Scheu, Stefan

2010-08-01

Prey from the decomposer subsystem may help sustain predator populations in arable fields. Adding organic residues to agricultural systems may therefore enhance pest control. We investigated whether resource addition (maize mulch) strengthens aboveground trophic cascades in winter wheat fields. Evaluating the flux of the maize-borne carbon into the food web after 9 months via stable isotope analysis allowed differentiating between prey in predator diets originating from the above- and belowground subsystems. Furthermore, we recorded aphid populations in predator-reduced and control plots of no-mulch and mulch addition treatments. All analyzed soil dwelling species incorporated maize-borne carbon. In contrast, only 2 out of 13 aboveground predator species incorporated maize carbon, suggesting that these 2 predators forage on prey from the above- and belowground systems. Supporting this conclusion, densities of these two predator species were increased in the mulch addition fields. Nitrogen isotope signatures suggested that these generalist predators in part fed on Collembola thereby benefiting indirectly from detrital resources. Increased density of these two predator species was associated by increased aphid control but the identity of predators responsible for aphid control varied in space. One of the three wheat fields studied even lacked aphid control despite of mulch-mediated increased density of generalist predators. The results suggest that detrital subsidies quickly enter belowground food webs but only a few aboveground predator species include prey out of the decomposer system into their diet. Variation in the identity of predator species benefiting from detrital resources between sites suggest that, depending on locality, different predator species are subsidised by prey out of the decomposer system and that these predators contribute to aphid control. Therefore, by engineering the decomposer subsystem via detrital subsidies, biological control by generalist predators may be strengthened.

Indirect X-ray Detectors Based on Inkjet-Printed Photodetectors with a Screen-Printed Scintillator Layer.

PubMed

Oliveira, Juliana; Correia, Vitor; Sowade, Enrico; Etxebarria, Ikerne; Rodriguez, Raul D; Mitra, Kalyan Y; Baumann, Reinhard R; Lanceros-Mendez, Senentxu

2018-04-18

Organic photodetectors (PDs) based on printing technologies will allow to expand the current field of PD applications toward large-area and flexible applications in areas such as medical imaging, security, and quality control, among others. Inkjet printing is a powerful digital tool for the deposition of smart and functional materials on various substrates, allowing the development of electronic devices such as PDs on various substrates. In this work, inkjet-printed PD arrays, based on the organic thin-film transistor architecture, have been developed and applied for the indirect detection of X-ray radiation using a scintillator ink as an X-ray absorber. The >90% increase of the photocurrent of the PDs under X-ray radiation, from about 53 nA without the scintillator film to about 102 nA with the scintillator located on top of the PD, proves the suitability of the developed printed device for X-ray detection applications.

Acoustic positioning and orientation prediction

NASA Technical Reports Server (NTRS)

Barmatz, Martin B. (Inventor); Aveni, Glenn (Inventor); Putterman, Seth (Inventor); Rudnick, Joseph (Inventor)

1990-01-01

A method is described for use with an acoustic positioner, which enables a determination of the equilibrium position and orientation which an object assumes in a zero gravity environment, as well as restoring forces and torques of an object in an acoustic standing wave field. An acoustic standing wave field is established in the chamber, and the object is held at several different positions near the expected equilibrium position. While the object is held at each position, the center resonant frequency of the chamber is determined, by noting which frequency results in the greatest pressure of the acoustic field. The object position which results in the lowest center resonant frequency is the equilibrium position. The orientation of a nonspherical object is similarly determined, by holding the object in a plurality of different orientations at its equilibrium position, and noting the center resonant frequency for each orientation. The orientation which results in the lowest center resonant frequency is the equilibrium orientation. Where the acoustic frequency is constant, but the chamber length is variable, the equilibrium position or orientation is that which results in the greatest chamber length at the center resonant frequency.

Direct versus Indirect and Individual versus Group Modes of Language Therapy for Children with Primary Language Impairment: Principal Outcomes from a Randomized Controlled Trial and Economic Evaluation

ERIC Educational Resources Information Center

Boyle, James M.; McCartney, Elspeth; O'Hare, Anne; Forbes, John

2009-01-01

Background: Many school-age children with language impairments are enrolled in mainstream schools and receive indirect language therapy, but there have been, to the authors' knowledge, no previous controlled studies comparing the outcomes and costs of direct and indirect intervention delivered by qualified therapists and therapy assistants, and…

The Magnetic and Shielding Effects of Ring Current on Radiation Belt Dynamics

NASA Technical Reports Server (NTRS)

Fok, Mei-Ching

2012-01-01

The ring current plays many key roles in controlling magnetospheric dynamics. A well-known example is the magnetic depression produced by the ring current, which alters the drift paths of radiation belt electrons and may cause significant electron flux dropout. Little attention is paid to the ring current shielding effect on radiation belt dynamics. A recent simulation study that combines the Comprehensive Ring Current Model (CRCM) with the Radiation Belt Environment (RBE) model has revealed that the ring current-associated shielding field directly and/or indirectly weakens the relativistic electron flux increase during magnetic storms. In this talk, we will discuss how ring current magnetic field and electric shielding moderate the radiation belt enhancement.

Seismic Station Installation Orientation Errors at ANSS and IRIS/USGS Stations

USGS Publications Warehouse

Ringler, Adam T.; Hutt, Charles R.; Persfield, K.; Gee, Lind S.

2013-01-01

Many seismological studies depend on the published orientations of sensitive axes of seismic instruments relative to north (e.g., Li et al., 2011). For example, studies of the anisotropic structure of the Earth’s mantle through SKS‐splitting measurements (Long et al., 2009), constraints on core–mantle electromagnetic coupling from torsional normal‐mode measurements (Dumberry and Mound, 2008), and models of three‐dimensional (3D) velocity variations from surface waves (Ekström et al., 1997) rely on accurate sensor orientation. Unfortunately, numerous results indicate that this critical parameter is often subject to significant error (Laske, 1995; Laske and Masters, 1996; Yoshizawa et al., 1999; Schulte‐Pelkum et al., 2001; Larson and Ekström, 2002). For the Advanced National Seismic System (ANSS; ANSS Technical Integration Committee, 2002), the Global Seismographic Network (GSN; Butler et al., 2004), and many other networks, sensor orientation is typically determined by a field engineer during installation. Successful emplacement of a seismic instrument requires identifying true north, transferring a reference line, and measuring the orientation of the instrument relative to the reference line. Such an exercise is simple in theory, but there are many complications in practice. There are four commonly used methods for determining true north at the ANSS and GSN stations operated by the USGS Albuquerque Seismological Laboratory (ASL), including gyroscopic, astronomical, Global Positioning System (GPS), and magnetic field techniques. A particular method is selected based on site conditions (above ground, below ground, availability of astronomical observations, and so on) and in the case of gyroscopic methods, export restrictions. Once a north line has been determined, it must be translated to the sensor location. For installations in mines or deep vaults, this step can include tracking angles through the one or more turns in the access tunnel leading to the vault (e.g., GSN station WCI in Wyandotte Cave, Indiana). Finally, the third source of error comes from the ability of field engineers to orient the sensor relative to the reference line. In order to quantify bounds on the errors in each step in the orientation process, we conducted a series of tests at the ASL using twelve GSN and ANSS field engineers. The results from this exercise allow us to estimate upper bounds on the precision of our ability to orient instruments, as well as identify the sources of error in the procedures. We are also able to identify systematic bias of various true‐north‐finding methods relative to one another. Although we are unable to estimate the absolute accuracy of our orientation measurements due to our inability to identify true north without some error, the agreement between independent methods for finding true north provides confidence in the different approaches, assuming no systematic bias. Finally, our study neglects orientation errors that are beyond the control of the field engineer during a station visit. These additional errors can arise from deviations in the sensitive axes of the instruments relative to the case markings, processing errors (Holcomb, 2002) when comparing horizontal orientations relative to other sensors (e.g., borehole installations), and deviations of the sensitive axes of instruments from true orthogonality (e.g., instruments with separate modules such as the Streckeisen STS‐1).

Crystalline, Highly Oriented MOF Thin Film: the Fabrication and Application.

PubMed

Fu, Zhihua; Xu, Gang

2017-05-01

The thin film of metal-organic frameworks (MOFs) is a rapidly developing research area which has tremendous potential applications in many fields. One of the major challenges in this area is to fabricate MOF thin film with good crystallinity, high orientation and well-controlled thickness. In order to address this challenge, different appealing approaches have been studied intensively. Among various oriented MOF films, many efforts have also been devoted to developing novel properties and broad applications, such as in gas separator, thermoelectric, storage medium and photovoltaics. As a result, there has been a large demand for fundamental studies that can provide guidance and experimental data for further applications. In this account, we intend to present an overview of current synthetic methods for fabricating oriented crystalline MOF thin film and bring some updated applications. We give our perspective on the background, preparation and applications that led to the developments in this area and discuss the opportunities and challenges of using crystalline, highly oriented MOF thin film. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Light-dependent magnetoreception: orientation behaviour of migratory birds under dim red light.

PubMed

Wiltschko, Roswitha; Munro, Ursula; Ford, Hugh; Stapput, Katrin; Wiltschko, Wolfgang

2008-10-01

Magnetic compass orientation in migratory birds has been shown to be based on radical pair processes and to require light from the short wavelength part of the spectrum up to 565 nm Green. Under dim red light of 645 nm wavelength and 1 mW m(-2) intensity, Australian silvereyes and European robins showed a westerly tendency that did not change between spring and autumn, identifying it as a 'fixed direction' response. A thorough analysis revealed that this orientation did not involve the inclination compass, but was a response based on the polarity of the magnetic field. Furthermore, in contrast to the orientation under short-wavelength light, it could be disrupted by local anaesthesia of the upper beak where iron-containing receptors are located, indicating that it is controlled by these receptors. The similarity of the response under dim red light to the response in total darkness suggests that the two responses may be identical. These findings indicate that the observed 'fixed direction' response under dim red light is fundamentally different from the normal compass orientation, which is based on radical pair processes.

Nonlinear Y-Like Receptive Fields in the Early Visual Cortex: An Intermediate Stage for Building Cue-Invariant Receptive Fields from Subcortical Y Cells.

PubMed

Gharat, Amol; Baker, Curtis L

2017-01-25

Many of the neurons in early visual cortex are selective for the orientation of boundaries defined by first-order cues (luminance) as well as second-order cues (contrast, texture). The neural circuit mechanism underlying this selectivity is still unclear, but some studies have proposed that it emerges from spatial nonlinearities of subcortical Y cells. To understand how inputs from the Y-cell pathway might be pooled to generate cue-invariant receptive fields, we recorded visual responses from single neurons in cat Area 18 using linear multielectrode arrays. We measured responses to drifting and contrast-reversing luminance gratings as well as contrast modulation gratings. We found that a large fraction of these neurons have nonoriented responses to gratings, similar to those of subcortical Y cells: they respond at the second harmonic (F2) to high-spatial frequency contrast-reversing gratings and at the first harmonic (F1) to low-spatial frequency drifting gratings ("Y-cell signature"). For a given neuron, spatial frequency tuning for linear (F1) and nonlinear (F2) responses is quite distinct, similar to orientation-selective cue-invariant neurons. Also, these neurons respond to contrast modulation gratings with selectivity for the carrier (texture) spatial frequency and, in some cases, orientation. Their receptive field properties suggest that they could serve as building blocks for orientation-selective cue-invariant neurons. We propose a circuit model that combines ON- and OFF-center cortical Y-like cells in an unbalanced push-pull manner to generate orientation-selective, cue-invariant receptive fields. A significant fraction of neurons in early visual cortex have specialized receptive fields that allow them to selectively respond to the orientation of boundaries that are invariant to the cue (luminance, contrast, texture, motion) that defines them. However, the neural mechanism to construct such versatile receptive fields remains unclear. Using multielectrode recording, we found a large fraction of neurons in early visual cortex with receptive fields not selective for orientation that have spatial nonlinearities like those of subcortical Y cells. These are strong candidates for building cue-invariant orientation-selective neurons; we present a neural circuit model that pools such neurons in an imbalanced "push-pull" manner, to generate orientation-selective cue-invariant receptive fields. Copyright © 2017 the authors 0270-6474/17/370998-16$15.00/0.

17 CFR 1.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... that directly or indirectly controls such individual, partnership, corporation or association; or (viii) A business affiliate that, directly or indirectly is controlled by or is under common control with... equivalent of fixed-price sales of the cash products and by-products of such commodity by the same person...