Search results for " processing"
showing 10 items of 7549 documents
Ewald Hering und die Gegenfarbtheorie
1996
Ewald Hering's color-opponent-theory is still considered one of the foundations of the visual sciences. Prior to Hering, Hermann v. Helmholtz introduced a theory of color appearance, which was based primarily on the physical aspects of the stimulus. In contrast to Helmholtz, Hering's theory strongly emphasized the subject's perception of color. As a consequence, Hering considered Helmholtz' theory inadequate. Contrary to some historical accounts, he did not object to Helmholtz's three-receptor explanation for color-mixture. Instead of Helmholtz' fundamental colors red, green, and blue, Hering suggested that the colors possess opponent character: blue-yellow; red-green; and, black-white. Hel…
The time course of face matching by internal and external features: Effects of context and inversion.
2010
AbstractEffects of context and inversion were studied in face matching tasks by measuring proportion correct as a function of exposure duration. Subjects were instructed to attend either internal features (task A) or external features (task B) and matched two consecutive face stimuli, which included either congruent, incongruent, or no facial context features. In congruent contexts matching performance rose fast and took very similar courses for both types of facial features. With no contexts internal and external features were found to be matched at an equal speed, while incongruent contexts seriously delayed matching performance for internal, but not for external features. Analysing the e…
Depth Enhancement by Fusion for Passive and Active Sensing
2012
This paper presents a general refinement procedure that enhances any given depth map obtained by passive or active sensing. Given a depth map, either estimated by triangulation methods or directly provided by the sensing system, and its corresponding 2-D image, we correct the depth values by separately treating regions with undesired effects such as empty holes, texture copying or edge blurring due to homogeneous regions, occlusions, and shadowing. In this work, we use recent depth enhancement filters intended for Time-of-Flight cameras, and adapt them to alternative depth sensing modalities, both active using an RGB-D camera and passive using a dense stereo camera. To that end, we propose …
Bioaccessibility of tocopherols, carotenoids, and ascorbic acid from milk- and soy-based fruit beverages: Influence of food matrix and processing
2012
A study was made of the effect of high-pressure processing (HPP) and thermal treatment (TT) on plant bioactive compounds (tocopherols, carotenoids, and ascorbic acid) in 12 fruit juice-milk beverages and of how the food matrix [whole milk (JW), skimmed milk (JS), and soy milk (JSy)] modulates their bioaccessibility (%). HPP (400 MPa/40 °C/5 min) produced a significant decrease in carotenoid and ascorbic acid bioaccessibility in all three beverages and maintained the bioaccessibility of tocopherols in JW and JS while decreasing it in JSy. TT (90 °C/30 s) produced a significant decrease in tocopherol and carotenoid bioaccessibility in all three beverages and increased the bioaccessibility of …
Comparing the effects of thermal and non-thermal technologies on pomegranate juice quality: A review.
2019
The consumption of pomegranate juice (PJ) has increased substantially since scientific literature reported its therapeutic benefits that are attributable to antioxidant, antimicrobial, anti-carcinogenic, and anti- inflammatory properties. The growing consumer demands for fresh and high-quality food products have led to the interest in non- thermal technologies for preservation of fruit juices. Although thermal pasteurization is the most widely used preservation technology, it has adverse effects on the nutritional and sensory quality of juices. Conversely, non- thermal technologies are suitable alternatives for preservation and without negative effects on the quality. However, there is limi…
Translational adaptation to heat stress is mediated by RNA 5‐methylcytosine in Caenorhabditis elegans
2021
Abstract Methylation of carbon‐5 of cytosines (m5C) is a post‐transcriptional nucleotide modification of RNA found in all kingdoms of life. While individual m5C‐methyltransferases have been studied, the impact of the global cytosine‐5 methylome on development, homeostasis and stress remains unknown. Here, using Caenorhabditis elegans, we generated the first organism devoid of m5C in RNA, demonstrating that this modification is non‐essential. Using this genetic tool, we determine the localisation and enzymatic specificity of m5C sites in the RNome in vivo. We find that NSUN‐4 acts as a dual rRNA and tRNA methyltransferase in C. elegans mitochondria. In agreement with leucine and proline bein…
Human cytomegalovirus pp71 stimulates major histocompatibility complex class i presentation of IE1-derived peptides at immediate early times of infec…
2013
ABSTRACT Suppression of major histocompatibility complex (MHC) class I-mediated presentation of human cytomegalovirus (HCMV) peptides is an important mechanism to avoid CD8 T lymphocyte recognition and killing of infected cells. Of particular interest is how MHC class I presentation of essential regulatory immediate early (IE) proteins of HCMV can be effectively compromised at times when known viral immunoevasins are not abundantly expressed. The tegument protein pp71 had been suggested to be involved in MHC class I downregulation. Intriguingly, this polypeptide is also critically engaged in the initial derepression of the major IE gene locus, leading to enhanced expression of IE proteins I…
Importance of force feedback for following uneven virtual paths with a stylus
2021
It is commonly known that a physical textured path can be followed by indirect touch through a probe also in absence of vision if sufficiently informative cues are delivered by the other sensory channels, but prior research indicates that the level of performance while following a virtual path on a touchscreen depends on the type and channel such cues belong to. The re-enactment of oriented forces, as they are induced by localized obstacles in probe-based exploration, may be important to equalize the performance between physical and virtual path following. Using a stylus attached to a force-feedback arm, an uneven path marked by virtual bars was traversed while time and positions were measu…
Combining haptics and inertial motion capture to enhance remote control of a dual-arm robot
2022
AbstractHigh dexterity is required in tasks in which there is contact between objects, such as surface conditioning (wiping, polishing, scuffing, sanding, etc.), specially when the location of the objects involved is unknown or highly inaccurate because they are moving, like a car body in automotive industry lines. These applications require the human adaptability and the robot accuracy. However, sharing the same workspace is not possible in most cases due to safety issues. Hence, a multi-modal teleoperation system combining haptics and an inertial motion capture system is introduced in this work. The human operator gets the sense of touch thanks to haptic feedback, whereas using the motion…
From medical data to simple virtual mock-up of scapulo-humeral joint
2008
The surgical operations of shoulder joint are guided by various principles: osteosynthesis in the case of fracture, osteotomy in order to correct a deformation or to modify the functioning of the joint, or implementation of articular prosthesis. At the end of the twentieth century, many innovations in the domains of biomechanics and orthopedic surgery have been performed. Nevertheless, theoretical and practical problems may appear during the operation (visual field of surgeon is very limited, quality and shape of the bone is variable depending on the patient). Biomechanical criteria of success are defined for each intervention. For example, the installation with success of prosthetic implan…