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https://www.readbyqxmd.com/read/28213690/anticipatory-postural-adjustments-associated-with-reaching-movements-are-programmed-according-to-the-availability-of-visual-information
#1
Roberto Esposti, Carlo Bruttini, Francesco Bolzoni, Paolo Cavallari
During goal-directed arm movements, the eyes, head, and arm are coordinated to look at and reach the target. We examined whether the expectancy of visual information about the target modifies Anticipatory Postural Adjustments (APAs). Ten standing subjects had to (1) move the eyes, head and arm, so as to reach, with both gaze and index-finger, a target of known position placed outside their visual field (Gaze-Reach); (2) look at the target while reaching it (Reach in Full Vision); (3) keep the gaze away until having touched it (Reach then Gaze) and (4) just Gaze without Reach the target...
February 17, 2017: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
https://www.readbyqxmd.com/read/28213397/regional-differences-in-the-preferred-e-vector-orientation-of-honeybee-ocellar-photoreceptors
#2
Yuri Ogawa, Willi Ribi, Jochen Zeil, Jan M Hemmi
In addition to compound eyes, honeybees (Apis mellifera) possess three single lens eyes called ocelli located on the top of the head. Ocelli are involved in head-attitude control and in some insects have been shown to provide celestial compass information. Anatomical and early electrophysiological studies have suggested that UV and blue-green photoreceptors in ocelli are polarization sensitive. However, their retinal distribution and receptor characteristics have not been documented. Here, we used intracellular electrophysiology to determine the relationship between the spectral and polarization sensitivity of photoreceptors and their position within the visual field of the ocelli...
February 17, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28213320/comparative-analysis-of-mosquito-diptera-culicidae-aedes-aegypti-liston-responses-to-the-insecticide-temephos-and-plant-derived-essential-oil-derived-from-piper-betle-l
#3
Prabhakaran Vasantha-Srinivasan, Sengottayan Senthil-Nathan, Athirstam Ponsankar, Annamalai Thanigaivel, Edward-Sam Edwin, Selvaraj Selin-Rani, Muthiah Chellappandian, Venkatraman Pradeepa, Jalasteen Lija-Escaline, Kandaswamy Kalaivani, Wayne B Hunter, Veeramuthu Duraipandiyan, Naif Abdullah Al-Dhabi
Resistance to treatments with Temephos or plant derived oil, Pb-CVO, between a field collected Wild Strain (WS) and a susceptible Laboratory Strain (LS) of Ae. aegypti were measured. The Temephos (0.1mg/L) showed the greatest percentage of mosquito mortality compared to Pb-CVO (1.5mg/L) in LS Ae. aegypti. However, WS Ae. aegypti was not significantly affected by Temephos (0.1mg/L) treatment compare to the Pb-CVO (1.5mg/L). However, both strains (LS and WS) when treated with Pb-CVO (1.5mg/L) displayed steady larval mortality rate across all instars...
February 14, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28213112/laminar-imaging-of-positive-and-negative-bold-in-human-visual-cortex-at-7t
#4
Alessio Fracasso, Peter R Luijten, Serge O Dumoulin, Natalia Petridou
Deciphering the direction of information flow is critical to understand the brain. Data from non-human primate histology shows that connections between lower to higher areas (e.g. retina→V1), and between higher to lower areas (e.g. V1←V2) can be dissociated based upon the distribution of afferent synapses at the laminar level. Ultra-high field scanners opened up the possibility to image brain structure and function at an unprecedented level of detail. Taking advantage of the increased spatial resolution available, it could theoretically be possible to disentangle activity from different cortical depths from human cerebral cortex, separately studying different compartments across depth...
February 14, 2017: NeuroImage
https://www.readbyqxmd.com/read/28212982/vision-science-and-adaptive-optics-the-state-of-the-field
#5
Susana Marcos, John S Werner, Stephen A Burns, William H Merigan, Pablo Artal, David A Atchison, Karen M Hampson, Richard Legras, Linda Lundstrom, Geungyoung Yoon, Joseph Carroll, Stacey S Choi, Nathan Doble, Adam M Dubis, Alfredo Dubra, Ann Elsner, Ravi Jonnal, Donald T Miller, Michel Paques, Hannah E Smithson, Laura K Young, Yuhua Zhang, Melanie Campbell, Jennifer Hunter, Andrew Metha, Grazyna Palczewska, Jesse Schallek, Lawrence C Sincich
Adaptive optics is a relatively new field, yet it is spreading rapidly and allows new questions to be asked about how the visual system is organized. The editors of this feature issue have posed a series of question to scientists involved in using adaptive optics in vision science. The questions are focused on three main areas. In the first we investigate the use of adaptive optics for psychophysical measurements of visual system function and for improving the optics of the eye. In the second, we look at the applications and impact of adaptive optics on retinal imaging and its promise for basic and applied research...
February 14, 2017: Vision Research
https://www.readbyqxmd.com/read/28212877/defining-outcomes-for-clinical-trials-of-leber-congenital-amaurosis-caused-by-gucy2d-mutations
#6
Samuel G Jacobson, Artur V Cideciyan, Alexander Sumaroka, Alejandro J Roman, Jason Charng, Monica Lu, Shreyasi Choudhury, Sharon B Schwartz, Elise Heon, Gerald A Fishman, Shannon E Boye
PURPOSE: To determine outcome measures for a clinical trial of Leber congenital amaurosis (LCA) associated with mutations in the GUCY2D gene. DESIGN: Retrospective observational case series. METHODS: 28 patients with GUCY2D-LCA (ages 2-59) were studied clinically and with chromatic full-field sensitivity testing (FST), optical coherence tomography (OCT), pupillometry, and the NEI Visual Function Questionnaire. RESULTS: FST permitted quantitation of cone and rod sensitivity in these patients with severe visual impairment...
February 14, 2017: American Journal of Ophthalmology
https://www.readbyqxmd.com/read/28212106/view-based-3-d-model-retrieval-a-benchmark
#7
An-An Liu, Wei-Zhi Nie, Yue Gao, Yu-Ting Su
View-based 3-D model retrieval is one of the most important techniques in numerous applications of computer vision. While many methods have been proposed in recent years, to the best of our knowledge, there is no benchmark to evaluate the state-of-the-art methods. To tackle this problem, we systematically investigate and evaluate the related methods by: 1) proposing a clique graph-based method and 2) reimplementing six representative methods. Moreover, we concurrently evaluate both hand-crafted visual features and deep features on four popular datasets (NTU60, NTU216, PSB, and ETH) and one challenging real-world multiview model dataset (MV-RED) prepared by our group with various evaluation criteria to understand how these algorithms perform...
February 15, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/28212053/transthoracic-echocardiography-pitfalls-and-limitations-as-delineated-at-cardiac-ct-and-mr-imaging
#8
Sachin B Malik, Natalie Chen, Rex A Parker, Joe Y Hsu
Transthoracic echocardiography ( TTE transthoracic echocardiography ) is a critical tool in the field of clinical cardiology. It often serves as one of the first-line imaging modalities in the evaluation of cardiac disease owing to its low cost, portability, widespread availability, lack of ionizing radiation, and ability to evaluate both anatomy and function of the heart. Consequently, a large majority of patients undergoing a cardiac computed tomography (CT) or magnetic resonance (MR) imaging examination will have a TTE transthoracic echocardiography available for review...
February 17, 2017: Radiographics: a Review Publication of the Radiological Society of North America, Inc
https://www.readbyqxmd.com/read/28211793/a-novel-field-emission-microscopy-method-to-study-field-emission-characteristics-of-freestanding-carbon-nanotube-array
#9
Yunhan Li, Yonghai Sun, David Jaffray, John T W Yeow
Field emission (FE) uniformity and mechanism of emitter failure of freestanding carbon nanotube (CNT) arrays have not been well studied due to the difficulty of observing and quantifying FE performance of each emitter in CNT arrays. Herein a field emission microscopy (FEM) method based on Poly(methyl methacrylate) (PMMA) thin film is proposed to study the FE uniformity and CNT emitter failure of freestanding CNT arrays. FE uniformity of freestanding CNT arrays and different levels of FE current contributions from each emitter in the arrays are recorded and visualized...
February 17, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28211246/dna-amplification-in-the-field-move-over-pcr-here-comes-lamp
#10
Patricia L M Lee
It would not be an exaggeration to say that among molecular technologies, it is PCR (polymerase chain reaction) that underpins the discipline of molecular ecology as we know it today. With PCR, it has been possible to target the amplification of particular fragments of DNA, which can then be analysed in a multitude of ways. The capability of PCR to amplify DNA from a mere handful of copies further means that conservationists and ecologists are able to sample DNA unobtrusively and with minimal disturbance to the environment and the organisms of interest...
March 2017: Molecular Ecology Resources
https://www.readbyqxmd.com/read/28211206/variable-familial-exudative-vitreoretinopathy-in-a-family-harbouring-variants-in-both-fzd4-and-tspan12
#11
Patrik Schatz, Arif O Khan
PURPOSE: To report a family affected by familial exudative vitreoretinopathy (FEVR) in which more severe disease phenotypes segregated with digenic rather than monogenic variants in FEVR-related genes. METHODS: Phenotype was documented with high-resolution imaging of retinal structure and wide-field fundus photography. Next-generation sequencing (NGS) of known genes involved in FEVR was performed. RESULTS: Three affected individuals within a family with FEVR presented with variable disease severity...
February 16, 2017: Acta Ophthalmologica
https://www.readbyqxmd.com/read/28211185/a-comparison-of-goldmann-iii-v-and-spatially-equated-test-stimuli-in-visual-field-testing-the-importance-of-complete-and-partial-spatial-summation
#12
Jack Phu, Sieu K Khuu, Barbara Zangerl, Michael Kalloniatis
PURPOSE: Goldmann size V (GV) test stimuli are less variable with a greater dynamic range and have been proposed for measuring contrast sensitivity instead of size III (GIII). Since GIII and GV operate within partial summation, we hypothesise that actual GV (aGV) thresholds could predict GIII (pGIII) thresholds, facilitating comparisons between actual GIII (aGIII) thresholds with pGIII thresholds derived from smaller GV variances. We test the suitability of GV for detecting visual field (VF) loss in patients with early glaucoma, and examine eccentricity-dependent effects of number and depth of defects...
March 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28211176/peripheral-aberrations-in-adult-hyperopes-emmetropes-and-myopes
#13
Uchechukwu L Osuagwu, Marwan Suheimat, David A Atchison
PURPOSE: To determine differences in peripheral aberrations in hyperopic, emmetropic and myopic groups. METHODS: Cycloplegic peripheral aberrations for 5 mm pupils were measured at 39 locations across 42° × 32° of right eye visual fields with a COAS-HD Hartmann-Shack aberrometer in nine hyperopes (mean age 29 ± 5 years, spherical equivalent refraction M + 1.47 ± 0.58 D), 20 emmetropes (28 ± 7 years, +0.06 ± 0.36 D) and 20 myopes (27 ± 6 years, -2...
March 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28210958/does-global-astrocytic-calcium-signaling-participate-in-awake-brain-state-transitions-and-neuronal-circuit-function
#14
Celia Kjaerby, Rune Rasmussen, Mie Andersen, Maiken Nedergaard
We continuously need to adapt to changing conditions within our surrounding environment, and our brain needs to quickly shift between resting and working activity states in order to allow appropriate behaviors. These global state shifts are intimately linked to the brain-wide release of the neuromodulators, noradrenaline and acetylcholine. Astrocytes have emerged as a new player participating in the regulation of brain activity, and have recently been implicated in brain state shifts. Astrocytes display global Ca(2+) signaling in response to activation of the noradrenergic system, but whether astrocytic Ca(2+) signaling is causative or correlative for shifts in brain state and neural activity patterns is not known...
February 16, 2017: Neurochemical Research
https://www.readbyqxmd.com/read/28210832/benefits-of-an-android-based-tablet-application-in-primary-screening-for-eye-diseases-in-a-rural-population-india
#15
Sayed Ahmed Imtiaz, Sannapaneni Krishnaiah, Sunil Kumar Yadav, Balasubramaniam Bharath, Ramanathan V Ramani
To investigate the effectiveness, efficiency and cost gains in collecting patient eye health information from remote rural villages of India by trained field investigators through an Android Based Tablet Application namely 'Sankara Electronic Remote Vision Information System (SERVIS)". During January and March 2016, a population based cross-sectional study was conducted in three Indian states employing SERVIS and manual method. The SERVIS application has a 48-items survey instrument programed into the application...
April 2017: Journal of Medical Systems
https://www.readbyqxmd.com/read/28210181/causes-of-irreversible-unilateral-or-bilateral-blindness-in-the-al-baha-region-of-the-kingdom-of-saudi-arabia
#16
Huda Farhan Alghamdi
PURPOSE: To determine the causes of irreversible unilateral and bilateral blindness that cannot be rehabilitated medically, optically nor surgically in Al Baha province, Kingdom of Saudi Arabia. METHODS: There were a retrospective chart review and examination of patients presenting to King Fahad Hospital Al Baha, Saudi Arabia, with unilateral or bilateral blindness from June 2011 to September 2011. Blindness was defined as best corrected visual acuity (BCVA) of less than 0...
July 2016: Saudi Journal of Ophthalmology: Official Journal of the Saudi Ophthalmological Society
https://www.readbyqxmd.com/read/28210047/the-effect-of-visual-field-condition-on-kinetic-in-upper-extremities-and-e-m-g-in-lower-extremities-while-performing-reaching-in-normal-adults
#17
Hyekang Park, Youngeun Kang, Minah Yoo, Bomjin Lee, Jeongok Yang, Joongsook Lee, Dongwook Han, Taeyoung Oh
[Purpose] The aims of this study was to investigate mean velocity and angle of shoulder joint, activation of tibialis anterior and gastrocnemius according to both eyes, dominant eye and non-dominant eye condition during reaching task in normal adults. [Subjects and Methods] Our research recruited 24 participants (male 11, female 13) in Silla University. Participants were performed reaching out movement by conditions of both eye, dominants eye, non-dominants eye. The target was placed at 45 degree diagonal direction and distance far away 130% of their arm length...
January 2017: Journal of Physical Therapy Science
https://www.readbyqxmd.com/read/28210001/visualization-of-au-nanoparticles-buried-in-a-polymer-matrix-by-scanning-thermal-noise-microscopy
#18
Atsushi Yao, Kei Kobayashi, Shunta Nosaka, Kuniko Kimura, Hirofumi Yamada
Several researchers have recently demonstrated visualization of subsurface features with a nanometer-scale resolution using various imaging schemes based on atomic force microscopy. Since all these subsurface imaging techniques require excitation of the oscillation of the cantilever and/or sample surface, it has been difficult to identify a key imaging mechanism. Here we demonstrate visualization of Au nanoparticles buried 300 nm into a polymer matrix by measurement of the thermal noise spectrum of a microcantilever with a tip in contact to the polymer surface...
February 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28209965/high-amplitude-electrical-stimulation-can-reduce-elicited-neuronal-activity-in-visual-prosthesis
#19
Alejandro Barriga-Rivera, Tianruo Guo, Chih-Yu Yang, Amr Al Abed, Socrates Dokos, Nigel H Lovell, John W Morley, Gregg J Suaning
Retinal electrostimulation is promising a successful therapy to restore functional vision. However, a narrow stimulating current range exists between retinal neuron excitation and inhibition which may lead to misperformance of visual prostheses. As the conveyance of representation of complex visual scenes may require neighbouring electrodes to be activated simultaneously, electric field summation may contribute to reach this inhibitory threshold. This study used three approaches to assess the implications of relatively high stimulating conditions in visual prostheses: (1) in vivo, using a suprachoroidal prosthesis implanted in a feline model, (2) in vitro through electrostimulation of murine retinal preparations, and (3) in silico by computing the response of a population of retinal ganglion cells...
February 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28209521/impaired-visual-competition-in-patients-with-homonymous-visual-field-defects
#20
A C Geuzebroek, A V van den Berg
Intense visual training can lead to partial recovery of visual field defects caused by lesions of the primary visual cortex. However, the standard visual detection and discrimination tasks, used to assess this recovery process tend to ignore the complexity of the natural visual environment, where multiple stimuli continuously interact. Visual competition is an essential component for natural search tasks and detecting unexpected events. Our study focused on visual decision-making and to what extent the recovered visual field can compete for attention with the 'intact' visual field...
February 13, 2017: Neuropsychologia
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