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Transcranial focused ultrasound (tFUS) is an emerging method for non-invasive neuromodulation akin to transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). tFUS offers several advantages over electromagnetic methods including high spatial resolution and the ability to reach deep brain targets. Here we describe two experiments assessing whether tFUS could modulate mood in healthy human volunteers by targeting the right inferior frontal gyrus (rIFG), an area implicated in mood and emotional regulation. In a randomized, placebo-controlled, double-blind study, participants received 30 s of 500 kHz tFUS or a placebo control. Visual Analog Mood Scales (VAMS) assessed mood four times within an hour (baseline and three times after tFUS). Participants who received tFUS reported an overall increase in Global Affect (GA), an aggregate score from the VAMS scale, indicating a positive shift in mood. Experiment 2 examined resting-state functional (FC) connectivity using functional magnetic resonance imaging (fMRI) following 2 min of 500 kHz tFUS at the rIFG. As in Experiment 1, tFUS enhanced self-reported mood states and also decreased FC in resting state networks related to emotion and mood regulation. These results suggest that tFUS can be used to modulate mood and emotional regulation networks in the prefrontal cortex. [ABSTRACT FROM AUTHOR]

Automatically generating a summary of a sports video poses the challenge of detecting interesting moments, or highlights, of a game. Traditional sports video summarization methods leverage editing conventions of broadcast sports video that facilitate the extraction of high-level semantics. However, user-generated videos are not edited and, thus, traditional methods are not suitable to generate a summary. In order to solve this problem, this paper proposes a novel video summarization method that uses players’ actions as a cue to determine the highlights of the original video. A deep neural-network-based approach is used to extract two types of action-related features and to classify video segments into interesting or uninteresting parts. The proposed method can be applied to any sports in which games consist of a succession of actions. Especially, this paper considers the case of Kendo (Japanese fencing) as an example of a sport to evaluate the proposed method. The method is trained using Kendo videos with ground truth labels that indicate the video highlights. The labels are provided by annotators possessing a different experience with respect to Kendo to demonstrate how the proposed method adapts to different needs. The performance of the proposed method is compared with several combinations of different features, and the results show that it outperforms previous summarization methods. [ABSTRACT FROM AUTHOR]

Augmented reality (AR) marker hiding is a technique to visually remove AR markers in a real-time video stream. A conventional approach transforms a background image with a homography matrix calculated on the basis of a camera pose and overlays the transformed image on an AR marker region in a real-time frame, assuming that the AR marker is on a planar surface. However, this approach may cause discontinuities in textures around the boundary between the marker and its surrounding area when the planar surface assumption is not satisfied. This paper proposes a method for AR marker hiding without discontinuities around texture boundaries even under nonplanar background geometry without measuring it. For doing this, our method estimates the dense motion in the marker’s background by analyzing the motion of sparse feature points around it, together with a smooth motion assumption, and deforms the background image according to it. Our experiments demonstrate the effectiveness of the proposed method in various environments with different background geometries and textures. [ABSTRACT FROM AUTHOR]

Authoring video blogs requires a video editing process, which is cumbersome for ordinary users. Video summarization can automate this process by extracting important segments from original videos. Because bloggers typically have certain stories for their blog posts, video summaries of a blog post should take the author's intentions into account. However, most prior works address video summarization by mining patterns from the original videos without considering the blog author's intentions. To generate a video summary that reflects the blog author's intention, we focus on supporting texts in video blog posts and present a text-based method, in which the supporting text serves as a prior to the video summary. Given video and text that describe scenes of interest, our method segments videos and assigns to each video segment its priority in the summary based on its relevance to the input text. Our method then selects a subset of segments with content that is similar to the input text. Accordingly, our method produces different video summaries from the same set of videos, depending on the input text. We evaluated summaries generated from both blog viewers' and authors' perspectives in a user study. Experimental results demonstrate the advantages to the proposed text-based method for video blog authoring. [ABSTRACT FROM AUTHOR]

Standard video does not capture the 3D aspect of human motion, which is important for comprehension of motion that may be ambiguous. In this paper, we apply augmented reality (AR) techniques to give viewers insight into 3D motion by allowing them to manipulate the viewpoint of a motion sequence of a human actor using a handheld mobile device. The motion sequence is captured using a single RGB-D sensor, which is easier for a general user, but presents the unique challenge of synthesizing novel views using images captured from a single viewpoint. To address this challenge, our proposed system reconstructs a 3D model of the actor, then uses a combination of the actor's pose and viewpoint similarity to find appropriate images to texture it. The system then renders the 3D model on the mobile device using visual SLAM to create a map in order to use it to estimate the mobile device's camera pose relative to the original capturing environment. We call this novel view of a moving human actor a reenactment, and evaluate its usefulness and quality with an experiment and a survey. [ABSTRACT FROM AUTHOR]

Diminished reality aims to remove real objects from video images and fill in the missing regions with plausible background textures in real time. Most conventional methods based on image inpainting achieve diminished reality by assuming that the background around a target object is almost planar. This paper proposes a new diminished reality method that considers background geometries with less constraints than the conventional ones. In this study, we approximate the background geometry by combining local planes, and improve the quality of image inpainting by correcting the perspective distortion of texture and limiting the search area for finding similar textures as exemplars. The temporal coherence of texture is preserved using the geometries and camera pose estimated by visual-simultaneous localization and mapping (SLAM). The mask region that includes a target object is robustly set in each frame by projecting a 3D region, rather than tracking the object in 2D image space. The effectiveness of the proposed method is successfully demonstrated using several experimental environments. [ABSTRACT FROM PUBLISHER]

Peripheral somatosensory circuits are known to respond to diverse stimulus modalities. The energy modalities capable of eliciting somatosensory responses traditionally belong to mechanical, thermal, electromagnetic, and photonic domains. Ultrasound (US) applied to the periphery has also been reported to evoke diverse somatosensations. These observations however have been based primarily on subjective reports and lack neurophysiological descriptions. To investigate the effects of peripherally applied US on human somatosensory brain circuit activity we recorded evoked potentials using electroencephalography and conducted functional magnetic resonance imaging of blood oxygen level-dependent (BOLD) responses to fingertip stimulation with pulsed US. We found a pulsed US waveform designed to elicit a mild vibration sensation reliably triggered evoked potentials having distinct waveform morphologies including a large double-peaked vertex potential. Fingertip stimulation with this pulsed US waveform also led to the appearance of BOLD signals in brain regions responsible for somatosensory discrimination including the primary somatosensory cortex and parietal operculum, as well as brain regions involved in hierarchical somatosensory processing, such as the insula, anterior middle cingulate cortex, and supramarginal gyrus. By changing the energy profile of the pulsed US stimulus waveform we observed pulsed US can differentially activate somatosensory circuits and alter subjective reports that are concomitant with changes in evoked potential morphology and BOLD response patterns. Based on these observations we conclude pulsed US can functionally stimulate different somatosensory fibers and receptors, which may permit new approaches to the study and diagnosis of peripheral nerve injury, dysfunction, and disease. [ABSTRACT FROM AUTHOR]

Background: A superporous (85%) hydroxyapatite (HA) block was recently developed to improve osteoconductivity, but it was often not clinically successful when used to treat periodontal osseous defects. The primary purpose of this study is to develop a clinically applicable tissue-engineered bone substitute using this HA block and human alveolar periosteum-derived cells. Methods: Commercially available superporous HA blocks were acid treated and subjected to a three-dimensional (3D) culture for periosteal cell cultivation. Cells in the pore regions of the treated HA block were observed on the fracture surface by scanning electron microscopy. After osteogenic induction, the cell-HA complexes were implanted subcutaneously in nude mice. Osteoid formation was histologically evaluated. Results: Acid treatment enlarged the interconnections among pores, resulting in the deep penetration of periosteal cells. Under these conditions, cells were maintained for >2 weeks without appreciable cell death in the deep pore regions of the HA block. The cell-HA complexes that received in vitro osteogenic induction formed osteoids in pore regions of the treated HA blocks in vivo. In contrast, most pore regions in the nonpretreated, cell-free HA blocks that were evaluated in vivo remained cell free. Conclusions: Our findings suggest that an acid-treated HA block could function as a better scaffold for the 3D high-density culture of human periosteal cells in vitro, and this cell-HA complex had significant osteogenic potential at the site of implantation in vivo. Compared with the cell-free HA block, our cell-HA complex using periosteal cells, which are the most accessible for clinical periodontists, showed promising results as a bone substitute in periodontal regenerative therapy. [ABSTRACT FROM AUTHOR]

This paper proposes a method to render free viewpoint images from omnidirectional videos using a deformable 3-D mesh model. In the proposed method, a 3-D mesh is placed in front of a virtual viewpoint and deformed by using the pre-estimated omnidirectional depth maps that are selected on the basis of position and posture of the virtual viewpoint. Although our approach is fundamentally based on the model-based rendering approach that renders a geometrically correct virtualized world, in order to avoid the hole problem, we newly employ a viewpoint-dependent deformable 3-D model instead of the use of a unified 3-D model that is generally used in the model based rendering approach. In experiments, free-viewpoint images are generated from the omnidirectional video captured by an omnidirectional multi camera system to show the feasibility of the proposed method for walk-through applications in the virtualized environment. [ABSTRACT FROM AUTHOR]

New developments in fluorophores as well as in detection methods have fueled the rapid growth of optical imaging in the life sciences. Commercial widefield microscopes generally use arc lamps, excitation/emission filters and shutters for fluorescence imaging. These components can be expensive, difficult to maintain and preclude stable illumination. Here, we describe methods to construct inexpensive and easy-to-use light sources for optical microscopy using light-emitting diodes (LEDs). We also provide examples of its applicability to biological fluorescence imaging. [ABSTRACT FROM AUTHOR]

Camera parameter recovery from an image sequence is very important in many applications such as 3D model reconstruction, object recognition, robot navigation, and mixed reality. However, there is a problem concerning the precision in camera parameter estimation from the image sequence, because feature tracking errors and estimation errors are accumulated. In this paper, we propose a camera parameter estimation method which is based on using a number of markers with known 3D position, color, and shape, as well as natural features. Initially, the camera parameters and 3D positions of natural features are estimated efficiently in every frame by tracking both these markers and natural features. The accumulation of estimated errors is then minimized by specifying additional markers in some frames of input and optimizing parameters globally through the whole input. In the experiments, some results of 3D reconstruction show the validity of the proposed method. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(8): 12–20, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10702 [ABSTRACT FROM AUTHOR]

The acquisition of olfactory information and its early processing in mammals are modulated by brain states through sniffing behavior and neural feedback. We imaged the spatiotemporal pattern of odor-evoked activity in a population of output neurons (mitral/tufted cells, MTCs) in the olfactory bulb (OB) of head-restrained mice expressing a genetically-encoded calcium indicator. The temporal dynamics of MTC population activity were relatively simple in anesthetized animals, but were highly variable in awake animals. However, the apparently irregular activity in awake animals could be predicted well using sniff timing measured externally, or inferred through fluctuations in the global responses of MTC population even without explicit knowledge of sniff times. The overall spatial pattern of activity was conserved across states, but odor responses had a diffuse spatial component in anesthetized mice that was less prominent during wakefulness. Multi-photon microscopy indicated that MTC lateral dendrites were the likely source of spatially disperse responses in the anesthetized animal. Our data demonstrate that the temporal and spatial dynamics of MTCs can be significantly modulated by behavioral state, and that the ensemble activity of MTCs can provide information about sniff timing to downstream circuits to help decode odor responses., Molecular and Cellular Biology

Primary olfactory cortical areas receive direct input from the olfactory bulb, but also have extensive associational connections that have been mainly studied with classical anatomical methods. Here, we shed light on the functional properties of associational connections in the anterior and posterior piriform cortices (aPC and pPC) using optophysiological methods. We found that the aPC receives dense functional connections from the anterior olfactory nucleus (AON), a major hub in olfactory cortical circuits. The local recurrent connectivity within the aPC, long invoked in cortical autoassociative models, is sparse and weak. By contrast, the pPC receives negligible input from the AON, but has dense connections from the aPC as well as more local recurrent connections than the aPC. Finally, there are negligible functional connections from the pPC to aPC. Our study provides a circuit basis for a more sensory role for the aPC in odor processing and an associative role for the pPC., Molecular and Cellular Biology

New developments in fluorophores as well as in detection methods have fueled the rapid growth of optical imaging in the life sciences. Commercial widefield microscopes generally use arc lamps, excitation/emission filters and shutters for fluorescence imaging. These components can be expensive, difficult to maintain and preclude stable illumination. Here, we describe methods to construct inexpensive and easy-to-use light sources for optical microscopy using light-emitting diodes (LEDs). We also provide examples of its applicability to biological fluorescence imaging., Molecular and Cellular Biology

Summary Ultrasound has received widespread attention as an emerging technology for targeted, non-invasive neuromodulation based on its ability to evoke electrophysiological and motor responses in animals. However, little is known about the spatiotemporal pattern of ultrasound-induced brain activity that could drive these responses. Here, we address this question by combining focused ultrasound with wide-field optical imaging of calcium signals in transgenic mice. Surprisingly, we find cortical activity patterns consistent with indirect activation of auditory pathways rather than direct neuromodulation at the ultrasound focus. Ultrasound-induced activity is similar to that evoked by audible sound. Furthermore, both ultrasound and audible sound elicit motor responses consistent with a startle reflex, with both responses reduced by chemical deafening. These findings reveal an indirect auditory mechanism for ultrasound-induced cortical activity and movement requiring careful consideration in future development of ultrasonic neuromodulation as a tool in neuroscience research. [ABSTRACT FROM AUTHOR]