Transmodal (nonsensory-specific) regions sit at the confluence of different information streams, and play an important role in cognition. These regions are thought to receive and integrate information from multiple functional networks. However, little is known about (1) how transmodal cortices are functionally organized and (2) how this organization might facilitate information processing. In t...

This paper analyzes the use of ultrasonic echo amplitudes to evaluate the characteristics of the detected surfaces (such as distinguishing between walls and corners). The shape and surface characteristics of the environment, such as roughness or absorption coefficient, as well as the distance and the angle of incidence, have high influence on the amplitude of the echoes. As a consequence, the a...

To elucidate the mechanism of regional hemostasis in the left ventricular (LV) cavity during myocardial infarction, the blood pathway in LV cavity was examined with contrast echocardiography injected from the left atrium before and after coronary ligation in nine canines. Before coronary ligation, contrast echoes spread over LV cavity with one rush. After ligation, smokelike echoes indicating h...

Bats, using frequency-modulated echolocation sounds, can capture a moving target in real 3D space. The process by which they are able to accomplish this, however, is not completely understood. This work offers and analyzes a model for description of one mechanism that may play a role in the echolocation process of real bats. This mechanism allows for the localization of targets in 3D space from...

AIMS To test the hypothesis that inter-observer variability accounts for the wide variation in reported prevalences of fibrin strands on prosthetic heart valves and to develop criteria for their identification and reporting. METHODS AND RESULTS A videotape with 30 sequences of prosthetic heart valves imaged by transoesophageal echocardiography and showing abnormalities such as strands, microb...

[1] At various altitudes in the plasmasphere, sounder pulses from the Radio Plasma Imager (RPI) instrument on the IMAGE satellite can couple strongly to protons, a process revealed in echo time delay versus frequency forms that arrive at multiples of the local proton cyclotron period tp. Lower-altitude (<4000 km) versions of two of these proton cyclotron (PC) forms were previously observed in t...

Classification of plants according to their echoes is an elementary component of bat behavior that plays an important role in spatial orientation and food acquisition. Vegetation echoes are, however, highly complex stochastic signals: from an acoustical point of view, a plant can be thought of as a three-dimensional array of leaves reflecting the emitted bat call. The received echo is therefore...

The high squint diving SAR is widely used to provide the information in advance. Large squint angle deduces the deeper coupling of range and azimuth of SAR echoes which makes SAR imaging more difficult. Especially, the large range migration of the deep couple heavily burdens the imaging processing time and storage units. The diving motion of platform worsens the situation. This paper proposes t...

Echolocating big brown bats (Eptesicus fuscus) broadcast ultrasonic frequency-modulated (FM) biosonar sounds (20-100 kHz frequencies; 10-50 microseconds periods) and perceive target range from echo delay. Knowing the acuity for delay resolution is essential to understand how bats process echoes because they perceive target shape and texture from the delay separation of multiple reflections. Bat...

The use of echolocation for navigating in dense, cluttered environments is a challenge due to the need for rapid sampling of nearby objects in the face of delayed echoes from distant objects. In the wild, echolocating bats frequently encounter this situation when leaving the roost or while hunting. If long-delay echoes from a distant object are received after the next pulse is sent out, these "...