Optimized nonhyperbolic moveout correction equation of long-offset seismic data for TI media with an arbitrary spatial orientation

The conventional long-offset nonhyperbolic moveout equation is derived for the transverse isotropic media with a vertical symmetric axis（VTI）.It cannot be extended to the transverse isotropic media with an arbitrary spatial orientation of symmetry axis（ATI）.In this paper,we optimize a modified long-offset nonhyperbolic moveout equation for ATI media based on the conventional nonhyperbolic moveout equation and the exact analytical solution of the quartic moveout coefficient（A_4） and NMO velocity for ATI media that were derived in our previous work.Compared with the exact traveltimes of the ray-tracing algorithm for anisotropic media,this optimized equation can be used to calculate the traveltime varying with survey line azimuth in arbitrary strong or weak ATI media.It can replace the time-consuming, multi-offset,and multi-azimuth ray tracing method for forward modeling of long-offset reflection traveltimes in ATI media,which is useful to further anisotropic parameter inversion using long-offset nonhyperbolic moveout.

Expanding through the Emerald Isle:exploration and spatial orientation of non-native bank voles in Ireland

Whether introduced into a completely novel habitat or slowly expanding their current range,the degree to which animals can effciently explore and navigate new environments can be key to survival,ultimately determining population establishment and colonization success.We tested whether spatial orientation and exploratory behavior are associated with non-native spread in free-living bank voles(Myodes glareolus,N=43)from a population accidentally introduced to Ireland a century ago.We measured spatial orientation and navigation in a radial arm maze,and behaviors associated to exploratory tendencies and risk-taking in repeated open-feld tests,at the expansion edge and in the source population.Bank voles at the expansion edge re-visited unrewarded arms of the maze more,waited longer before leaving it,took longer to start exploring both the radial arm maze and the open feld,and were more risk-averse compared to conspecifcs in the source population.Taken together,results suggest that for this small mammal under heavy predation pressure,a careful and thorough exploration strategy might be favored when expanding into novel environments.

Inner Ear Size May Account for Spatial Orientation Differences Between Sexes

男性的空间方位感总体上比女性的要好,这是为什么呢?最近多伦多大学的研究者发现造成这种差别的主要原因是由于二者内耳的长度不同。

Pioneering Studies of Spatial Behavior in Animals: Ivane Beritashvili and Edward Tolman

Ivane S. Beritashvili’s doctrine of image-driven behavior was established in the late 1920s and finally extended in his books in English (1965;1971). It bears a strong resemblance to the concepts of purposive behavior and “cognitive maps” developed in parallel by Edward C. Tolman (1932;1948) and significantly anticipated respective modern concepts. John O’Keefe and his disciples May-Britt Moser and Edvard I. Moser received the Nobel Prize in 2014 for their discoveries of cells that constitute a navigation system in the brain. The latter fact brings us to the pioneers of the study of the spatial orientation of animals that figuratively speaking, provided the giant’s shoulders on which O’Keefe and the Mosers stood to receive their award. Beritashvili and Tolman upheld the holistic and goal-directed nature of spatial behavior. A major contribution of Beritashvili to the science of animal behavior was the demonstration of the universality of learning following a single presentation of an object vitally important to the animal: either a food object or a noxious signal. Beritashvili showed that such “image-driven” behavior has a strong spatial component, i.e., the image is projected into a definite point in space. Thus, he came to maintain that there is a class of behavior that is image-driven that does not require a repetition of associations. Tolman made several significant contributions to the field of experimental psychology. He thought of learning as developing from bits of knowledge and cognitions about the environment and how the organism relates to it. He examined the role that reinforcement plays in the way that rats learn their way through complex mazes. These experiments eventually led to the theory of latent learning which describes learning that occurs in the absence of an obvious reward. Tolman also strongly advocated the theory that rats learn the place where they have been rewarded rather than the particular movements required to get there. To a great extent, Tolman’s work determined the direction of American psychology in the 1930s-1950s. The contribution of Beritashvili and Tolman, thus, is the groundwork of modern studies of spatial cognitive processes in human and nonhuman animals.

Lumbar spine localisation method based on feature fusion

To eliminate unnecessary background information,such as soft tissues in original CT images and the adverse impact of the similarity of adjacent spines on lumbar image segmentation and surgical path planning,a two‐stage approach for localising lumbar segments is proposed.First,based on the multi‐scale feature fusion technology,a non‐linear regression method is used to achieve accurate localisation of the overall spatial region of the lumbar spine,effectively eliminating useless background information,such as soft tissues.In the second stage,we directly realised the precise positioning of each segment in the lumbar spine space region based on the non‐linear regression method,thus effectively eliminating the interference caused by the adjacent spine.The 3D Intersection over Union(3D_IOU)is used as the main evaluation indicator for the positioning accuracy.On an open dataset,3D_IOU values of 0.8339�0.0990 and 0.8559�0.0332 in the first and second stages,respectively is achieved.In addition,the average time required for the proposed method in the two stages is 0.3274 and 0.2105 s respectively.Therefore,the proposed method performs very well in terms of both pre-cision and speed and can effectively improve the accuracy of lumbar image segmentation and the effect of surgical path planning.

Inferior vestibular neuritis in a fighter pilot:A case report

Pilot spatial disorientation is a leading factor contributing to many fatal flying accidents. Spatial orientation is the product of integrative inputs from the proprioceptive, vestibular, and visual systems. Vestibular neuritis (VN) can lead to sudden pilot incapacitation in flight. VN is commonly diagnosed by demonstration of unilateral vestibular failure, as unilateral loss of caloric response. As this test reflects the function of the superior part of the vestibular nerve only, cases of pure inferior nerve neuritis will be lost. This paper describes a fighter pilot with symptoms suggestive of VN but with normal caloric test results. Further test showed unilateral loss of vestibular evoked myogenic potential. We believe that the pilot suffered from pure inferior nerve vestibular neuritis. VEMP plays a major role in the diagnosis of inferior nerve vestibular neuritis in pilots. Aeromedical concerns are also discussed.

HSPOG:An Optimized Target Recognition Method Based on Histogram of Spatial Pyramid Oriented Gradients

The Histograms of Oriented Gradients(HOG)can produce good results in an image target recognition mission,but it requires the same size of the target images for classification of inputs.In response to this shortcoming,this paper performs spatial pyramid segmentation on target images of any size,gets the pixel size of each image block dynamically,and further calculates and normalizes the gradient of the oriented feature of each block region in each image layer.The new feature is called the Histogram of Spatial Pyramid Oriented Gradients(HSPOG).This approach can obtain stable vectors for images of any size,and increase the target detection rate in the image recognition process significantly.Finally,the article verifies the algorithm using VOC2012 image data and compares the effect of HOG.

Directly patterned substrate-free plasmonic “nanograter” structures with unusual Fano resonances

The application of three-dimensional(3D)plasmonic nanostructures as metamaterials(MMs),nano-antennas,and other devices faces challenges in producing metallic nanostructures with easily definable orientations,sophisticated shapes,and smooth surfaces that are operational in the optical regime and beyond.Here,we demonstrate that complex 3D nanostructures can be readily achieved with focused-ion-beam irradiation-induced folding and examine the optical characteristics of plasmonic“nanograter”structures that are composed of free-standing Au films.These 3D nanostructures exhibit interesting 3D hybridization in current flows and exhibit unusual and well-scalable Fano resonances at wavelengths ranging from 1.6 to 6.4 mm.Upon the introduction of liquids of various refractive indices to the structures,a strong dependence of the Fano resonance is observed,with spectral sensitivities of 1400 nm and 2040 nm per refractive index unit under figures of merit of 35.0 and 12.5,respectively,for low-order and high-order resonance in the near-infrared region.This work indicates the exciting,increasing relevance of similarly constructed 3D free-standing nanostructures in the research and development of photonics and MMs.