Vertical Shift Research Articles

Eye movements reveal that young school children shift attention when solving additions and subtractions.

Adults shift their attention to the right or to the left along a spatial continuum when solving additions and subtractions, respectively. Studies suggest that these shifts not only support the exact computation of the results but also anticipatively narrow down the range of plausible answers when processing the operands. However, little is known on when and how these attentional shifts arise in childhood during the acquisition of arithmetic. Here, an eye-tracker with high spatio-temporal resolution was used to measure spontaneous eye movements, used as a proxy for attentional shifts, while children of 2nd (8 y-o; N=50) and 4th (10 y-o; N=48) Grade solved simple additions (e.g., 4+3) and subtractions (e.g., 3-2). Gaze patterns revealed horizontal and vertical attentional shifts in both groups. Critically, horizontal eye movements were observed in 4th Graders as soon as the first operand and the operator were presented and thus before the beginning of the exact computation. In 2nd Graders, attentional shifts were only observed after the presentation of the second operand just before the response was made. This demonstrates that spatial attention is recruited when children solve arithmetic problems, even in the early stages of learning mathematics. The time course of these attentional shifts suggests that with practice in arithmetic children start to use spatial attention to anticipatively guide the search for the answer and facilitate the implementation of solving procedures. RESEARCH HIGHLIGHTS: Additions and subtractions are associated to right and left attentional shifts in adults, but it is unknown when these mechanisms arise in childhood. Children of 8-10 years old solved single-digit additions and subtractions while looking at a blank screen. Eye movements showed that children of 8 years old already show spatial biases possibly to represent the response when knowing both operands. Children of 10 years old shift attention before knowing the second operand to anticipatively guide the search for plausible answers.

Evaluation of kV Triggered Fiducial Tracking for Prostate SBRT Intrafraction Motion Management.

Stereotactic body radiation therapy (SBRT) is a safe and effective treatment for localized prostate cancer. Given the high dose per fraction, a high degree of precision is needed during SBRT treatment delivery. Fiducial marker tracking is a means of monitoring intrafraction motion, ensuring precise treatment delivery and potentially allowing for decreased planning target volume (PTV) margins. We present a 5-year single institution experience to characterize the performance of fiducial tracking. We analyzed 132 consecutive patients treated at our institution with prostate SBRT between July 2017 and November 2022 using fiducial tracking with the TrueBeam Auto Beam Hold feature. Patients were treated using a 5-fraction dose escalation protocol, with many receiving a simultaneous integrated boost to the GTV up to 45 Gy. All patients underwent pre-treatment cone-beam CT and planar kV imaging with rigid registration to the fiducial markers. Cine kV images were acquired every 3-5 seconds during treatment delivery and the beam was paused when a fiducial deviated from a given 4 mm diameter tolerance region. Additional intrafraction 2D or 3D imaging techniques were then used to realign the fiducials. Data was retrieved from the record and verify system including: number and type of intrafraction images, number of treatment interruptions, number of and magnitude of shifts, and total treatment time. The average number of cine kV images acquired per fraction and for the total 5 fraction SBRT course were 86.6 ± 26.8 and 425.6 ± 136.8 respectively. Assuming 1.3 mGy/kV image, the fiducial tracking process delivered an average additional 55.3 cGy over the full treatment course. On average, the beam was paused 5.0 ± 2.5 times per fraction (range 1-21 interruptions) and shifts were applied 4.1 ± 2.1 times (range 0-10.2 times) per fraction. Over the 2560 total shifts applied for all the patients, the average(max) translations were 0.6 (12) mm vrt, 0.7 (22) mm lng, and 0.9 (5) mm lat and the average(max) rotations were 0.19 (5.9)° pitch, 0.01 (2.4)° roll, and 0.16 (6.4)° rtn. Overall, 2.4% of shifts were greater than the 4 mm PTV margin and 4.2% of vertical shifts were greater than the 2.5 mm posterior margin. Average fraction treatment time was 27 ± 9.7 minutes. Fiducial tracking affords the potential to increase daily treatment precision when delivering prostate SBRT. Our data indicate that the beam is typically paused several times during a prostate SBRT fraction, with occasional large shifts required, suggesting the importance of intrafraction motion management. Downsides of kV triggered fiducial tracking include extension of treatment times and delivery of additional radiation dose to the patient. We are investigating if this method of motion management might allow for a reduction in PTV margins to reduce normal tissue dosing.

A new method based on deep learning and image processing for detection of strabismus with the Hirschberg test

Strabismus is a condition in which one or both eyes do not work in parallel or in harmony. People with strabismus have one eye looking straight ahead while the other eye looks inwards, outwards, upwards or downwards. This condition can affect both eyes. Strabismus is a common eye condition that affects about 4 % of the world's population. Tests such as Hirschberg, Cover and Krimsky are used to detect strabismus. In the Hirschberg test, a light source is held at a distance of 50 cm so that it falls on the centre of each eye. The horizontal and vertical distance between the centre of gravity of the light reflected from the cornea and the centre of the pupil indicates the degree of strabismus. In this study, deep learning and image processing algorithms are used to detect the eye, corneal reflection, iris and pupil on a patient's facial image. Based on the Hirschberg test, the horizontal and vertical shifts for both eyes were measured to determine the patient's degree of strabismus. In this way, the Hirschberg test used in strabismus screening was performed automatically by software. The correct detection of the pupil and the light reflected from the cornea by the algorithm means that the eye has been measured correctly. The software was tested on the facial images of 88 strabismic patients of different sexes and ages. 91 % of the 88 patients, or 80 patients, had their left eye measured correctly. 90 % of the 88 patients, or 79 patients, had their right eye measured correctly. The results for each eye obtained from the correct measurements were found to have an error of maximum ± 2°. This error is due to the fact that a real eye is in three-dimensional space, while the digital eye image is in two-dimensional space, and was only observed in the test results of some patients. This algorithm can be tested on patients of all ages and is not affected by morphological differences in the patients' faces. Successful results have been observed experimentally that this newly proposed method can be used in strabismus screening.

Exchange Bias in Nanostructures: An Update.

Exchange bias (EB) is a unidirectional anisotropy occurring in exchange-coupled ferromagnetic/antiferromagnetic systems, such as thin films, core-shell particles, or nanostructures. In addition to a horizontal shift of the hysteresis loop, defining the exchange bias, asymmetric loops and even vertical shifts can often be found. While the effect is used in hard disk read heads and several spintronics applications, its origin is still not fully understood. Especially in nanostructures with their additional shape anisotropies, interesting and often unexpected effects can occur. Here, we provide an overview of the most recent experimental findings and theoretical models of exchange bias in nanostructures from different materials.

Levee Slurry Wall Assessment Using Ground Penetrating Radar, A Case Study

Levees are essential structures in places with high water level events. Therefore, it is important to make periodic monitoring of these structures to assess their condition. Some levees consist of slurry walls built with reinforced concrete. GSSI ground penetrating radar with 200, 400, and 900 MHz antenna was used to assess the rebar and concrete condition of the slurry wall along 300m of the Big Dam Bride levee, Little Rock, Arkansas, USA. GPR profiles indicate the deterioration in rebar and concrete from the reflections of the rebar and the differences in the rebar vertical depths which represent the change in the concrete properties. These vertical shifts in the rebar anomalies indicate that the concrete fractured and the discontinued slabs shifted upward or downward over the years, all field observations did not indicated any vertical shift or fracture in the concrete slabs, or is the presence of deterioration in the concrete above the rebar. Therefore, the deteriorated part will appear at a higher or lower levels related to the non deteriorated part. Also, non-uniform values of reflections for the same depth suggest the rebar deterioration as well. There were about 182m out of 300m of the studied levee are detroierated with various degrees of rebars and concrete deterioration. The GPR was found to be effective to detect the slurry wall's concrete and rebar deterioration. The result of this study indicates that the slurry wall of the levee is possibly unsafe and partially deteriorated.

Coexistence of tetragonal and cubic phase induced complex magnetic behaviour in CoMn2O4 nanoparticles

CoMn2O4, known for its extensive range of applications, has been subject to limited investigations regarding its structure dependent magnetic properties. Here, we have examined the structure dependent magnetic properties of CoMn2O4 nanoparticles synthesized through a facile coprecipitation technique and are characterized using x-ray diffractometer, x-ray photoelectron spectroscopy (XPS), RAMAN spectroscopy, transmission electron microscopy and magnetic measurements. Rietveld refinement of the x-ray diffraction pattern reveals the coexistence of 91.84% of tetragonal and 8.16% of cubic phase. The cation distribution for tetragonal and cubic phases are (Co0.94Mn0.06)[Co0.06Mn1.94]O4 and (Co0.04Mn0.96)[Co0.96Mn1.04]O4, respectively. While Raman spectra and selected area electron diffraction pattern confirm the spinel structure, both +2 and +3 oxidation states for Co and Mn confirmed by XPS further corroborate the cation distribution. Magnetic measurement shows two magnetic transitions, Tc1 at 165 K and Tc2 at 93 K corresponding to paramagnetic to a lower magnetically ordered ferrimagnetic state followed by a higher magnetically ordered ferrimagnetic state, respectively. While Tc1 is attributed to the cubic phase having inverse spinel structure, Tc2 corresponds to the tetragonal phase with normal spinel. In contrast to general temperature dependent H C observed in ferrimagnetic material, an unusual temperature dependent H C with high spontaneous exchange bias of 2.971 kOe and conventional exchange bias of 3.316 kOe at 50 K are observed. Interestingly, a high vertical magnetization shift (VMS) of 2.5 emu g−1 is observed at 5 K, attributed to the Yafet–Kittel spin structure of Mn3+ in the octahedral site. Such unusual results are discussed on the basis of competition between the non-collinear triangular spin canting configuration of Mn3+ cations of octahedral sites and collinear spins of tetrahedral site. The observed VMS has the potential to revolutionize the future of ultrahigh density magnetic recording technology.

Minor species in Venus’ night side troposphere as observed by VIRTIS-H/Venus Express

The 2.3μm spectral window has been used to constrain the composition of the lower atmosphere (in the 30–40 km altitude range) on the night side of Venus for more than thirty years. Here, we present a follow-up study of Marcq et al. (2008), but using the full VIRTIS-H/Venus Express data archive as well as an updated radiative transfer forward model. We are able to confirm a latitudinal increase of CO of about 30% between 0° and 60°N, as well as an anti-correlated vertical shift of OCS profile by about −1km in the same latitude range. Both variations are about twice smaller in the southern hemisphere. Correlations of low latitude CO and OCS variations with zonally shifted surface elevation is tentatively found. These results are consistent with CO and OCS variations resulting from the competition between local thermochemistry and a Hadley-cell-like general circulation, albeit influenced by the orography. Finally, no evidence for spatial variations of water vapor (combined H2O and HDO) or sulfur dioxide could be evidenced in this data set; better constraining possible variations of these species would require future missions to include infrared spectrometers operating at a spectral resolving power higher than ∼104, such as VenSpec-H onboard EnVision. *Plain Language Summary Remotely measuring the composition of the Venusian atmosphere below the clouds is challenging, yet yields invaluable insights about the atmospheric chemistry, circulation and interaction with the surface and interior of the planet. The VIRTIS-H instrument on board ESA’s Venus Express orbiter (2006–2014) provides a rich data set in this regard, thanks to its ability to observe and analyze, on the night side of the planet, the infrared radiation emitted by the deep atmospheric layers. The results of our analyses confirm the previously observed trends for the variations of two trace gases (carbon monoxide and carbonyl sulfide) with latitude, explained by the combined effects of chemical reactions and transport by the atmospheric circulation. Variations of carbon monoxide may also be linked to the variations of ground elevation, confirming the link between surface topography and atmospheric circulation. However, we were unable to separate the signature of heavy water vapor from ordinary water vapor or to detect any variations in sulfur dioxide, both of which require more powerful infrared instruments such as those planned on future Venus orbiters such as ESA’s EnVision.

Exchange Bias and Vertical Magnetic Shift on Co−CoO Thin Films

AbstractThis work reports the results of an experimental study on Si(001)/Au(111)/Co/CoO/ZrO2 elaborated by electron beam evaporation. The chemical composition of the oxidized state of cobalt and zirconium cover layers derived from metallic deposition is confirmed by X‐ray photoelectron spectroscopy (XPS). Magnetic properties are probed by magneto‐optical Kerr effect (MOKE). The polar magneto‐optic Kerr effect (PMOKE) measurements reveal that the cooling at 77 K under an applied magnetic field induces an exchange coupling which is manifested by a positive exchange bias (EB) field accompanied by a negative vertical shift of the magnetization. In longitudinal magneto‐optical Kerr effect (LMOKE), the exchange coupling depends on the orientation of the applied measuring magnetic field. It is found that both the exchange field shift rate hshift and the vertical shift rate in magnetization mshift exhibit a peak at 45° between the applied field and the [100] in‐plane direction which may be associated with the presence of uncompensated pinned spins at the Co−CoO interface.

Overburden 4D seismic analysis: Influence of stress and pore-pressure changes accounting for elastic contrast between a reservoir and its anisotropic surrounding rocks

Time-lapse (4D) seismic data analysis is widely used to monitor producing hydrocarbon or CO2 storage reservoirs and their surroundings. The influence of potentially significant undrained pore-pressure changes around depleting (or injected) reservoirs appears to be neglected in most previous studies. The 4D seismic response in the overburden depends on the stress changes and strains induced by the reservoir. These alterations may challenge stable infill drilling and well integrity. We have used anisotropic static elastic moduli from laboratory measurements for two different field shales to predict stress changes and strains in the surroundings of a depleting reservoir through geomechanical modeling. These mechanical changes are used to quantify undrained pore-pressure changes using anisotropic poroelastic theory constrained with Skempton parameters. Finally, an empirical rock-physics model quantifies the impact of these poroelastic changes on vertical velocity changes and time strains. This model explicitly quantifies the individual contributions to vertical velocity changes from undrained pore pressure, mean stress, and shear stress above (and below) the depleting reservoir. We find that a stiffer surrounding rock exhibits significantly larger vertical time strains and time shifts in the overburden as compared with softer surrounding rocks because of promoted arching. Undrained overburden pore-pressure changes significantly contribute to overburden velocity changes and time shifts. Ignoring anisotropy in the Skempton parameters can lead to overestimating the overburden undrained pore pressure and time shifts after reservoir depletion. The anisotropy in static stiffnesses significantly impacts the dynamic changes in the vertical direction, and the dynamic changes are particularly pronounced in the vicinity of the reservoir. We find how a tailored rock-physics model can link 4D seismic data and geomechanics to separate stress, strain, and pore-pressure changes — all essential for optimizing drilling and production.

The Role of Neutral Wind Velocity and Its Vertical Component on Predictability of Formation and Localization of Sporadic E (Es)

The formation and localization of sporadic E (Es) layers predicted by the ion vertical drift velocity and its vertical change in the lower thermosphere during nighttime are shown analytically and by numerical simulations. The consideration of the existence of a minimum negative value of the vertical change of the ion vertical drift velocity as a necessary condition of formation of the Es layer and determining ion convergence rate into this layer is extended in case of the presence of vertical wind. Upward vertical wind can shift the convergence regions upward, while downward vertical wind shifts them downward, unlike the cases of the presence of only meridional and zonal winds. It also changes the ion convergence rate compared to the one with just a horizontal wind. It is shown for the first time that the upward constant wind also causes the convergence of ions with the maximum rate in the region where the ion-neutral collision frequency is equal to their cyclotron frequency. While demonstrating the presented theory by numerical simulations, HWM14 data is used for the meridional and zonal wind velocity profiles and the presence of its vertical component is assumed. In this case, in addition to the estimated ion drift velocity and its vertical changes, their initial distribution and ambipolar diffusion also determine the development of ion convergence/divergence processes. For a small magnitude of vertical wind velocity, its significant influence on the ions/electrons behavior is demonstrated, which shows the importance of both tidal wind and wind changes caused by the propagation of atmospheric gravity waves on the formation of the Es layer. In this theoretical research, it is shown that the realistic profile of the wind velocity, which takes into account the vertical component along with its zonal and meridional ones, is important for the prediction of the Es layers formation, as well as regions of ion depletion.

The effect of linear shear current on head-on collision of solitons

Head-on collision of two solitary waves in the presence of linear shear currents is studied by the use of the High-Level Green–Naghdi (HLGN) theory. The finite difference method is used to solve the HLGN model in the time-domain simulation. The initial values are obtained by the steady solution of solitary waves in the presence of linear shear currents. Shear currents with different velocities are considered to assess their effect on the solitary-wave collision. Three aspects of the head-on collision process in the presence of shear current are studied, namely, the wave elevation, velocity field, and particle trajectory. Results show that the background linear shear current significantly affects the wave elevation, velocity field, and particle trajectory during the head-on collision. It is observed that in the presence of the current, the wave elevation is narrower near the maximum surface displacement and is wider near the still-water level. It is also shown that near the seafloor, the horizontal velocity is opposite of the current direction, while it is following the current direction near the free surface. The opposite shear current results in the formation of a vortex in the fluid field. At the point of the collision, the vortex appears at a lower vertical position and shifts upstream of the current direction. Following the particle trajectories in the presence of the shear current, it is observed that the particles do not return to their initial positions after the head-on collisions, and the loop motions of the particles become smaller with larger current velocities.

Geochemical approach for decoding the paleoenvironmental and depositional evolution of a coastal lacustrine Konservat-Lagerstätte (Early Cretaceous, south-Central Pyrenees)

The lithographic limestone of La Pedrera de Meià (LPM) in south-Central Pyrenees (NE Spain) is considered one of the best preserved lacustrine-coastal successions of the Early Cretaceous in Europe, hosting a taxonomically diverse record of Barremian biota. While this Konservat-Lagerstätte has been extensively surveyed for paleontological purposes, little is known about the paleoenvironmental and depositional conditions prevailing during the formation of this fossil lagerstätte deposit. LPM limestone is made up of a homogeneous, dark gray to pale brown, faintly laminated 50 m-thick succession of micrite-rich intervals. To shed light on the environmental conditions of deposition, 303 rock samples were studied using a multiproxy approach based on different techniques including petrography, SEM-EDX, XRD, ICP-MS, XRF, Rare Earth Element distributions and C and O stable isotope geochemistry. The combination of sedimentological and geochemical data reveals a vertical shift of facies from littoral to profundal environments and then returning to littoral conditions. Profundal facies are made up of filament-rich mudstones originated from in situ precipitation of micrite either through biotically mediated or physico-chemical processes in undisturbed low energy settings, under anoxic conditions, characterized by the presence of transported terrestrial and lacustrine organisms that are exquisitely well-preserved. Littoral areas are characterized by the presence of in situ charophytes, smooth ostracods, and miliolid foraminifera that accumulated in mud-rich facies indicating low/moderate-energy, shallow-water, and relatively oxygenated conditions. Stable isotopic data and elemental geochemistry suggest a hydrologically closed to semi-closed lacustrine system with a restricted water circulation encouraging dysoxic to anoxic conditions in profundal sediments. Paleoproductivity proxies suggest a good correlation between catchment-derived siliciclastic discharge to the lake and primary productivity peaks. Furthermore, a decline in terrigenous input coupled with a reduction of meteoric water entrance to the lake is interpreted based on elemental proxies derived from paleosalinity and paleoredox analysis. Collectively, the strontium/barium (Sr/Ba) ratios, the sparse presence of miliolid foraminifera, and the isotopic signatures indicate an increase in salinity toward the younger intervals of the lake infilling, although their ultimate causes are unclear (i.e., increased evaporation, or a combination of reduced meteoric input and sporadic marine inputs might explain our data). The present work shows the importance of performing detailed multiproxy geochemical-sedimentological studies to better constrain the unique paleoenvironmental and paleohydrological conditions associated with the exceptional preservation of fossil biotas in Konservat-Lagerstätte deposits in analogous depositional settings.

The structural analysis of the periplasmic domain of Sinorhizobium meliloti chemoreceptor McpZ reveals a novel fold and suggests a complex mechanism of transmembrane signaling.

Chemotaxis is a fundamental process whereby bacteria seek out nutrient sources and avoid harmful chemicals. For the symbiotic soil bacterium Sinorhizobium meliloti, the chemotaxis system also plays an essential role in the interaction with its legume host. The chemotactic signaling cascade is initiated through interactions of an attractant or repellent compound with chemoreceptors or methyl-accepting chemotaxis proteins (MCPs). S. meliloti possesses eight chemoreceptors to mediate chemotaxis. Six of these receptors are transmembrane proteins with periplasmic ligand-binding domains (LBDs). The specific functions of McpW and McpZ are still unknown. Here, we report the crystal structure of the periplasmic domain of McpZ (McpZPD) at 2.7 Å resolution. McpZPD assumes a novel fold consisting of three concatenated four-helix bundle modules. Through phylogenetic analyses, we discovered that this helical tri-modular domain fold arose within the Rhizobiaceae family and is still evolving rapidly. The structure, offering a rare view of a ligand-free dimeric MCP-LBD, reveals a novel dimerization interface. Molecular dynamics calculations suggest ligand binding will induce conformational changes that result in large horizontal helix movements within the membrane-proximal domains of the McpZPD dimer that are accompanied by a 5 Å vertical shift of the terminal helix toward the inner cell membrane. These results suggest a mechanism of transmembrane signaling for this family of MCPs that entails both piston-type and scissoring movements. The predicted movements terminate in a conformation that closely mirrors those observed in related ligand-bound MCP-LBDs.

The new shift perturbation method with applications to vibrational problems

Employing variable horizontal and vertical shifts for the unperturbed solution, a new perturbation method is proposed. The new method is named as the shift perturbation method. The existing perturbation methods are interpreted with respect to the horizontal and vertical shifts for the unperturbed solution. The new method is applied to some well-known vibrational problems. The method is capable of producing admissible approximate solutions for a wide range of problems such as the free and forced vibrations of the Duffing equation, equations with quadratic and cubic nonlinearities, variable amplitude nonlinear problems, and boundary layer problems. A variant of the method also produced valid solutions for large perturbation parameters.

The Use of Regional Data Assimilation to Improve Numerical Simulations of Diurnal Characteristics of Precipitation during an Active Madden–Julian Oscillation Event over the Maritime Continent

This study examines the impact of regional data assimilation on diurnal characteristics of precipitation and winds over the Maritime Continent (MC) using a set of cloud-permitting-scale (~3 km) numerical simulations with the mesoscale community Weather Research and Forecasting (WRF) model and the NCEP Gridpoint Statistical Interpolation (GSI)-based ensemble-3DVAR hybrid data assimilation system. Numerical experiments focus on January 2018, when a well-defined, active Madden–Julian Oscillation (MJO) propagated through the MC region. Available conventional and satellite data are assimilated. Results show that simulated precipitation with data assimilation generally agrees better with satellite-derived rainfall than the control simulation without data assimilation. Simulations with data assimilation also reproduce the diurnal cycle of precipitation better, especially for the timing of the precipitation peak. Data assimilation modulates the overstrong (overweak) diurnal forcing over the land (ocean) in the control simulation. The vertical phase shift of the thermodynamic environment, associated with the timing of vertical motion transition along with low-level water vapor supplies, results in maximum precipitation occurring later, especially over land. To further demonstrate the impact of data assimilation, an additional experiment assimilates NASA Cyclone Global Navigation Satellite System (CYGNSS)-derived ocean surface winds. The results indicate that the assimilation of CYGNSS data exhibits an evident impact on the diurnal variation of surface variables and a similar shift in the diurnal cycle of precipitation. Overall, this study highlights the importance of regional data assimilation in improving the representation of precipitation over the MC, paving the way for a better understanding of the interactions of local diurnal convective precipitation cycles with MJO.

Oblique multi-periscopic prism for field expansion of homonymous hemianopia.

Oblique Fresnel peripheral prisms have been used for field expansion in homonymous hemianopia mobility such as walking and driving. However, limited field expansion, low image quality, and small eye scanning range limit their effectiveness. We developed a new oblique multi-periscopic prism using a cascade of rotated half-penta prisms, which provides 42° horizontal field expansion along with 18° vertical shift, high image quality, and wider eye scanning range. Feasibility and performance of a prototype using 3D-printed module are demonstrated by raytracing, photographic depiction, and Goldmann perimetry with patients with homonymous hemianopia.

Dimensionality engineering dependence of vertical magnetization shift and magnetic anisotropy evolution in manganite superlattices

The manganite superlattices consisting of a ferromagnetic La0.7Sr0.3MnO3 (LSMO) metal and a G-type antiferromagnetic SrMnO3 (SMO) insulator have been investigated in this work. Two very intriguing effects have been observed in these LSMO/SMO superlattices. The first one is the coexistence of the robust exchange bias and the evident vertical magnetization shift in the thicker superlattices. The second is the magnetic anisotropy variation from planar to perpendicular with increasing SMO layer thickness. These two novel phenomena have been confirmed by the electric transport anisotropy measurements and the microscopic magnetic domain switching images. Moreover, the X-ray linear dichroism experiments and first-principle calculations have revealed the orbital reconstruction dependence on the SMO layer thickness. It is noteworthy that the vertical magnetization shift and perpendicular magnetic anisotropy are usually observed in intrinsic out-of-plane magnetic easy axis materials such as SrRuO3-based heterostructures. However, the spins within LSMO films preferably orient towards the in-plane direction. Therefore, a new microscopic method for vertical magnetization shift and magnetic anisotropy manipulation has been developed, enabling the discovery of emergent phenomena as well as the control of the magnetic properties.

Spatial and Temporal Abnormalities of Spontaneous Fixational Saccades and Their Correlates With Positive and Cognitive Symptoms in Schizophrenia.

Visual fixation is a dynamic process, with the spontaneous occurrence of microsaccades and macrosaccades. These fixational saccades are sensitive to the structural and functional alterations of the cortical-subcortical-cerebellar circuit. Given that dysfunctional cortical-subcortical-cerebellar circuit contributes to cognitive and behavioral impairments in schizophrenia, we hypothesized that patients with schizophrenia would exhibit abnormal fixational saccades and these abnormalities would be associated with the clinical manifestations. Saccades were recorded from 140 drug-naïve patients with first-episode schizophrenia and 160 age-matched healthy controls during ten separate trials of 6-second steady fixations. Positive and negative symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). Cognition was assessed using the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Patients with schizophrenia exhibited fixational saccades more vertically than controls, which was reflected in more vertical saccades with angles around 90° and a greater vertical shift of horizontal saccades with angles around 0° in patients. The fixational saccades, especially horizontal saccades, showed longer durations, faster peak velocities, and larger amplitudes in patients. Furthermore, the greater vertical shift of horizontal saccades was associated with higher PANSS total and positive symptom scores in patients, and the longer duration of horizontal saccades was associated with lower MCCB neurocognitive composite, attention/vigilance, and speed of processing scores. Finally, based solely on these fixational eye movements, a K-nearest neighbors model classified patients with an accuracy of 85%. Conclusions: Our results reveal spatial and temporal abnormalities of fixational saccades and suggest fixational saccades as a promising biomarker for cognitive and positive symptoms and for diagnosis of schizophrenia.

Master-slave synchronization in the Duffing-van der Pol and Φ6Duffing oscillators

AbstractIn this work a master-slave configuration to obtain synchronization between the double-well Duffing-van der Pol (master system) and the three-well Φ6Duffing oscillators (slave system) is studied. For this configuration, we analyze the system when the dissipative and one that combines the elastic and dissipative couplings are used. Whenever the dissipative coupling is used, we observed a vertical shift synchronization in the slave system. However, when the combination of the elastic and dissipative couplings is used, the vertical shift disappears obtaining complete synchronization. We resort to perturbation method to corroborate analytically these kind of synchronization, when the master system provides an harmonic function to the slave system. These synchronizations are numerically corroborated.

Giant Exchange-Bias-Like Effect at Low Cooling Fields Induced by Pinned Magnetic Domains in Y2 NiIrO6 Double Perovskite.

Exchange bias (EB) is highly desirable for widespread technologies. Generally, conventional exchange-bias heterojunctions require excessively large cooling fields for sufficient bias fields, which are generated by pinned spins at the interface of ferromagnetic and antiferromagnetic layers. It is crucial for applicability to obtain considerable exchange-bias fields with minimum cooling fields. Here, an exchange-bias-like effect is reported in a double perovskite, Y2 NiIrO6 , which shows long-range ferrimagnetic ordering below 192 K. It displays a giant bias-like field of 1.1 T with a cooling field of only 15Oe at 5 K. This robust phenomenon appears below 170 K. This fascinating bias-like effect is the secondary effect of the vertical shifts of the magnetic loops, which is attributed to the pinned magnetic domains due to the combination of strong spin-orbit coupling on Ir, and antiferromagnetically coupled Ni- and Ir-sublattices. The pinned moments in Y2 NiIrO6 are present throughout the full volume, not just at the interface as in conventional bilayer systems.