Manipulation Of Orientation Research Articles

The Fragility of the Near-Hand Effect

Recent literature has demonstrated that hand position can affect visual processing, a set of phenomena termed Near Hand Effects (NHEs). Across four studies we looked for single-hand NHEs on a large screen when participants were asked to discriminate stimuli based on size, colour, and orientation (Study 1), to detect stimuli after a manipulation of hand shaping (Study 2), to detect stimuli after the introduction of a peripheral cue (Study 3), and finally to detect stimuli after a manipulation of screen orientation (Study 4). Each study failed to find a NHE. Further examination of the pooled data using a Bayesian analysis also failed to reveal positive evidence for faster responses or larger cueing effects near a hand. These findings suggest that at least some NHEs may be surprisingly fragile, which dovetails with the recent proposition that NHEs may not form a unitary set of phenomena (Gozli & Deng, 2018). The implication is that visual processing may be less sensitive to hand position across measurement techniques than previously thought, and points to a need for well-powered, methodologically rigorous studies on this topic in the future.

Crystallographic orientation control and optical properties of GaN nanowires.

The optical and electrical properties of nitride materials are closely related to their crystallographic orientation. Here, we report our effort on crystallographic orientation manipulation of GaN NWs using vapour–liquid–solid hydride vapour phase epitaxy (VLS-HVPE). The growth orientations of the GaN NWs are tuned from the polar c-axis to the non-polar m-axis by simply varying the supply of III precursors on various substrates, including c-, r, m-plane sapphire, (111) silicon and (0001) GaN. By varying the size of the Ni/Au catalyst, we found that the catalyst size has a negligible influence on the growth orientation of GaN NWs. All these demonstrate that the growth orientation of the GaN NWs is dominated by the flow rate of the precursor, regardless of the catalyst size and the substrate adopted. Moreover, the optical properties of GaN NWs were characterized using micro-photoluminescence, revealing that the observed red luminescence band (near 660 nm) is related to the lateral growth of the GaN NWs. The work presented here will advance the understanding of the VLS process of GaN NWs and represents a step forward towards controllable GaN NW growth.

Manipulation of cellular orientation and migration by internalized magnetic particles

Cellular orientation and migration are mediated by internalized Fe3O4 nanoparticles with an external magnetic field in a particle-concentration dependent manner.

Prepublication: Optical trapping and orientation manipulation of 2D inorganic materials using a linearly polarized laser beam

Prepublication: Optical trapping and orientation manipulation of 2D inorganic materials using a linearly polarized laser beam

The manipulation of magnetic coercive field and orientation of magnetic anisotropy via electric fields

We report the effects of the electric field on the magnetic coercive field (Hc) and uniaxial magnetic anisotropy (UMA) orientation of polycrystalline Ni film grown on an unpoled (0 1 1) [Pb(Mg1/3Nb2/3)O3](1−x)–[PbTiO3]x (PMN-PT) single crystal substrate. Under various electric fields, normalized magnetic hysteresis loops of Ni films change in width; this represents the change of coercive field (ΔHc). Loop shapes are found to depend on the angle between the magnetic field and the sample, where changes in the shape reveal a small rotation of UMA. All these changes show that the magnetic properties vary periodically with a periodic electric field, by strain-mediated magnetoelectric coupling in the Ni/Ag/PMN-PT/Ag heterostructure. The poled PMN-PT produces strains under electric fields in the range of −4.2 kV cm−1 ⩽ E ⩽ 4.2 kV cm−1, then transfers it to Ni films resulting in changes to its Hc and UMA. The curves of the in-plane Hc and strain, at two mutually orthogonal directions, represent butterfly patterns versus the applied electric field. In addition, the changes observed in both the Hc and strain show asymmetric features in two orthogonal directions, which results in a small rotation angle of the UMA of Ni as the electric field decreases. The effective manipulation of magnitude and orientation of magnetic anisotropy via electric fields in ferromagnetic/ferroelectric (FM/FE) heterostructures is an important step towards controlling the magnetic tunnel junctions.

First-principles design of spintronics materials

Abstract Spintronics is one of the most promising next generation information technology, which uses the spins of electrons as information carriers and possesses potential advantages of speeding up data processing, high circuit integration density, and low energy consumption. However, spintronics faces a number of challenges, including spin generation and injection, long distance spin transport, and manipulation and detection of spin orientation. In solving these issues, new concepts and spintronics materials were proposed one after another, such as half metals, spin gapless semiconductors, and bipolar magnetic semiconductors. Topological insulators can also be viewed as a special class of spintronics materials, with their surface states used for pure spin generation and transportation. In designing these spintronics materials, first-principles calculations play a very important role. This article attempts to give a brief review of the basic principles and theoretical design of these materials. Meanwhile, we also give some attentions to the antiferromagnetic spintronics, which is mainly based on antiferromagnets and has aroused much interest in recent years.

Magnetization switching by combining electric field and spin-transfer torque effects in a perpendicular magnetic tunnel junction.

Effective manipulation of magnetization orientation driven by electric field in a perpendicularly magnetized tunnel junction introduces technologically relevant possibility for developing low power magnetic memories. However, the bipolar orientation characteristic of toggle-like magnetization switching possesses intrinsic difficulties for practical applications. By including both the in-plane (T//) and field-like (T⊥) spin-transfer torque terms in the Landau-Lifshitz-Gilbert simulation, reliable and deterministic magnetization reversal can be achieved at a significantly reduced current density of 5×109 A/m2 under the co-action of electric field and spin-polarized current, provided that the electric-field pulse duration exceeds a certain critical value τc. The required critical τc decreases with the increase of T⊥ strength because stronger T⊥ can make the finally stabilized out-of-plane component of magnetization stay in a larger negative value. The power consumption for such kind of deterministic magnetization switching is found to be two orders of magnitude lower than that of the switching driven by current only.

When Parents Know Little about What Happened: Parent-guided Conversations, Stress, and Young Children's Eyewitness Memory.

This study examined how 4- to 7-year-olds' memories for a stressor were influenced by conversations with a parent who had little knowledge of the target event, and the stress children experienced before, during, and after the event. Children (N = 43) watched a mildly stressful video before talking about it with a parent. Parents were asked to focus on either the children's feelings or the content of the video itself. A researcher interviewed the children about their memory following the conversation. Behavioral and physiological measures of children's stress were collected at multiple stages. Children recalled more inaccurate information with the parent than with the interviewer. Younger age and parent insecure attachment were associated with poorer memory. Manipulation of parents' emotion orientation did not predict memory, but individual differences in the talk did, although in different ways from what would be expected from research on conversations about shared events. Less stress (according to self-reported happiness and observed negative affect) before and after, but not during, the stressor was linked with better memory. Implications for children's memory in legal settings are discussed. Copyright © 2016 John Wiley & Sons, Ltd.

Reproductive isolation between Zaluzianskya species: the influence of volatiles and flower orientation on hawkmoth foraging choices.

Floral trait differences between related species may play a key role in reproductive isolation imposed by pollinators. Volatile emissions can influence pollinator choice, but how they act in combination with traits such as flower orientation is rarely studied. We compared flower-opening patterns, morphology, colour, orientation and volatile emissions for two closely related species of Zaluzianskya and their natural hybrids. Hawkmoth pollinators were tested for preference between flowers of the two species, and between flowers with manipulations of volatiles or orientation. Flowers of Z.natalensis and Z.microsiphon open at night and day, respectively, but they overlap during early evening, when hawkmoths showed a strong preference for Z.natalensis. The species have similar flower size and colour, but Z.natalensis emits more floral volatiles in the evening and presents flowers vertically face-up as opposed to horizontally in Z.microsiphon, whereas natural hybrids are intermediate. Adding methyl benzoate and linalool to flowers of Z.microsiphon did not increase hawkmoth attraction, but re-orientation of flowers to face vertically increased attraction when scent cues were present, whereas re-orientation of Z.natalensis flowers to face horizontally decreased attraction. This study highlights the importance of flower orientation in imposing reproductive isolation.

Vitamin B12 deficiency: Characterization of psychometrics and MRI morphometrics

Objectives: Vitamin B12 is essential for the integrity of the central nervous system. However, performances in different cognitive domains relevant to vitamin B12 deficiency remain to be detailed. To date, there have been limited studies that examined the relationships between cognitions and structural neuroimaging in a single cohort of low-vitamin B12 status. The present study aimed to depict psychometrics and magnetic resonance imaging (MRI) morphometrics among patients with vitamin B12 deficiency, and to examine their inter-relations.Methods: We compared 34 consecutive patients with vitamin B12 deficiency (serum level ≤250 pg/ml) to 34 demographically matched controls by their cognitive performances and morphometric indices of brain MRI. The correlations between psychometrics and morphometrics were analyzed.Results: The vitamin B12 deficiency group had lower scores than the controls on total scores of Mini-Mental Status Examination (MMSE) and Cognitive Abilities Screening Instrument (CASI) (both P < 0.05), language (P < 0.01), orientation (P < 0.01), and mental manipulation (P < 0.05). The patients also showed a greater frontal horn ratio than the controls (P < 0.05). Bicaudate ratio, fronto-occipital ratio, uncotemporal index, and normalized interuncal distance all showed a strong correlation with the total score of MMSE and CASI (all P < 0.01). Among these psychometric and morphometric indices, pronounced correlations between bicaudate ratio and long-term memory, mental manipulation, orientation, language, and verbal fluency were noted (all P < 0.01).Discussion: Vitamin B12 deficiency is associated with a global cognition decline with language, orientation, and mental manipulation selectively impaired. Preferential atrophy in frontal regions is the main neuroimaging feature. Although the frontal ratio highlights the relevant atrophy among patients, the bicaudate ratio might be the best index on the basis of its strong association with global cognition and related cognitive domains, implying dysfunction of fronto-subcortical circuits as the fundamental pathogenesis related to vitamin B12 deficiency.

Development of computer play pedagogy intervention for children with low conceptual understanding in basic mathematics operation using the dyscalculia feature approach

This study describes the development of a basic computer-based play pedagogy intervention using a dyscalculia-remedy-oriented approach such as repetition and number orientation manipulation, and the investigation of its effect on children displaying dyscalculia characteristics. This computer play was evaluated in a group of 50 seven-year-old Malaysian children, who were low achievers in mathematics subject and were divided into control and intervention group. The intervention group engaged with the newly developed computer play for an hour per day for five consecutive days, while the control group attended normal classroom learning for the same time period. Overall post-test scores indicated that children from the intervention group performed significantly better than the control group after the five-day intervention period by 57.9%. Number disorientation and arithmetic operation confusion, which are common amongst the children displaying dyscalculia characteristics, were also significantly reduced after the intervention. This implies that the children benefitted from the computer play.

Molecular orientation and electronic structure at organic heterojunction interfaces

Due to the highly anisotropic nature of π-conjugated molecules, the molecular orientation in organic thin films can significantly affect light absorption, charge transport, energy level alignment (ELA) and hence device performance. Synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy represents a powerful technique for probing molecular orientation. The aim of this review paper is to provide a balanced assessment on the investigation of molecular orientation at the organic–organic heterojunction (OOH) interface by NEXAFS, as well as the gap-states mediated orientation dependent energy level alignment at OOH interfaces. We highlight recent progress in elucidating molecular orientation at OOH interfaces dominated by various interfacial interactions, gap-states controlled orientation dependent energy level alignments at OOH interfaces, and the manipulations of molecular orientation and ELA in OOH.

Nano-Composite manufacturing using the Electro-Orientation method of Micro/Nano-Particles in a liquid polymer with mechanical characteristics analysis

A new technology for manufacturing micro/nano composites by utilizing an electric field to fabricate particle orientations in a polymer liquid state is developed and its thermo-mechanical properties are tested. This method allows the manipulation of the local orientation of the submerged micro/nano size particles in a liquid matrix. The study demonstrates that the technology is able to locally manipulate the particle orientation and applicable diverse metal/non-metal inclusions in a polymer matrix. The theoretical background of this process includes the dielectrophoresis, diploe moment, and electrophoresis of particles in a polymer matrix. Electrophoresis is an important phenomenon in the orientation of non-spherical particles in a continuous phase. Attempts were made to distribute several types of metal and non-metal particles in a liquid epoxy, in order to test the effects of electrophoresis under an electric field; the rotation and alignment of the particles were clearly observed and pictures were taken. The mathematical models of the kinetic movements caused by the electrophoretic force are also presented here. The results obtained from the experiment indicate the effectiveness of the proposed method and validate the suggested mathematical models, including all of the expanded manipulation.

Inter-hemispheric dynamics revealed by reaction time in the Dimond paradigm.

The Dimond paradigm (DP) consists of tachistoscopically presenting two stimuli to be discriminated--either both stimuli in a single visual hemifield or one in each. The DP has recently been implemented using predecessors to index homotopy of the callosal fibre projection with reaction time (RT) as the dependent measure. Using simple perceptual discrimination tasks, it has recently been reported that the advantage of the unilateral stimulation condition significantly decreases with practice. This effect has been interpreted as being due to the plasticity of the callosal network. Two experiments were designed to replicate these two little-known effects, namely callosal homotopy and callosal network plasticity. In addition, new evidence of another type of callosal network plasticity, termed "callosal network dispatching", was sought by introducing double manipulation of orientations of both stimulus-contours and inter-stimulus arrays to the DP. Strong support for the callosal homotopy and callosal network plasticity effects was obtained. In addition, evidence for a "callosal network dispatcher" effect accrued.

Magnetochromatic thin-film microplates.

A new type of magnetochromatic material is developed based on thin-film interference of microplates self-assembled from super-paramagnetic nanocrystals. Dynamic optical tuning can be achieved through orientational manipulation of free-standing super-paramagnetic thin-film microplates using external magnetic fields.

A novel, new robotic platform for natural orifice distal pancreatectomy.

Laparoendoscopic technology has revolutionized the practice of surgery; however, surgeons have not widely accepted laparoscopic techniques for pancreatic surgeries due to the complexity of the operation. Natural orifice transluminal endoscopic surgery (NOTES) offers a great new potential for pancreatic procedures, with early data showing benefits of reduced visible scarring and the potential for decreased wound infections, hernias, pain, and postoperative complications. However, there are significant limitations to the currently used flexible endoscopy tools, including a diminished visual field, spatial orientation and tissue manipulation issues, and 2-dimensional visual feedback. We have adopted a novel snake-like robot, the minimally invasive cardiac surgery (MICS) robot, which addresses these issues. In the current pilot study, the MICS robot was evaluated for transrectal distal pancreas exploration and resection in 2 nonsurvival porcine models. Abdominal navigation and accessing the pancreas was investigated in the first pig, and based on its success, pancreas resection was studied in pig 2. The MICS robot was successful in accessing and visualizing the right upper, left upper, and left lower quadrants of the abdomen in pig 1 and was able to perform a successful complex NOTES procedure with distal pancreas resection in pig 2, with only minimal laparoscopic retraction assistance. In conclusion, preliminary results showing the MICS robot in natural orifice distal pancreatectomy are positive. Enhancements to optics and instrumentation will help further increase the usability in pancreatic interventions. Future indications may include transgastric NOTES approaches, endoluminal procedures, and single-port applications.

Effect of crystal orientation in Cu(In,Ga)Se 2 fabricated by multi-layer precursor method on its cell performance

Abstract Cu(In,Ga)Se2 (CIGS) films with different crystal orientations and Ga/(In + Ga), Ga/III, profiles are fabricated by the so-called “multi-layer precursor method”, utilizing multi-layer co-evaporation of material sources. In this literature, the crystal orientation and averaged Ga/III near the CIGS surface, estimated from the Ga/III profile, are investigated to improve the cell performance, especially open-circuit voltage (VOC). It is revealed that the VOC increases and more enhances with (220/204)-oriented CIGS absorbers, when the averaged Ga/III near the CIGS surface increases. The conversion efficiency of the solar cell on flexible stainless steel substrate is ultimately improved by the manipulations of the crystal orientation, namely, I(220/204)/I(112) of approximately 1.7, and the averaged Ga/III near the CIGS surface of 0.38 under the multi-layer precursor method.

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

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 magnetic 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.

Multi-Dimensional Manipulation of Yeast Cells Using a LP$_{11}$ Mode Beam

We report a new method for constructing a single fiber optical tweezers, which can realize multi-dimensional manipulation of trapped yeast cells by using a LP11 mode beam excited in a normal communication single core optical fiber. This allows a simple and convenient orientation control on the trapped yeast cells. The LP11 mode beam, both for generating trap and orientation manipulation, has been modulated by using the tension and twisting loaded on the fiber. We present experimental results of controllable deflection and orientation manipulation of the yeast cells. To the best of our knowledge, it is the first report about the trapped yeast cells being driven by the normal single fiber optical tweezers in multi dimensions, and it constitutes a new development for single fiber optical trapping and makes possible of more practical applications in the biomedical research fields.

Too close for comfort: Stimulus valence moderates the influence of motivational orientation on distance perception.

The relationship between approach and avoidance motivational orientations and valenced stimuli has previously been discussed in relation to physical distance. However, it has remained unclear whether approach and avoidance can actually change how people perceive the physical distance to valenced stimuli. Drawing on research on motivational orientation and valence as well as the motivated perception account, we predicted that valenced stimuli incompatible with motivational orientation would be perceived as closer than compatible stimuli because they motivate the goal of resolving the inconsistency arising from discrepant affective information. This prediction was supported in a series of 4 experiments. Findings were consistent across different manipulations of motivational orientation, including motor movements (Experiments 1 and 2) and cognitive procedures (Experiments 3 and 4), and across different types of stimuli, including abstract words (Experiments 1, 2, and 4) and photos of concrete objects (Experiment 3). Experiment 4 further investigated the mechanism behind the influence of incompatibility versus compatibility between motivational orientation and valence on distance perception. The findings showed that, relative to compatibility, incompatibility resulted in participants solving more anagrams, presumably because the goal-related motivational state gave rise to a general state of activation. Furthermore, perceptual estimates were correlated with the activity of the Behavioral Inhibition System (BIS) and the activity of the Behavioral Activation System (BAS) relative to the BIS, further suggesting that goal-related motivation may be associated with perception. Overall, the present research adds to a growing body of evidence suggesting that visual perception is shaped by motivational considerations.