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McGovern Kristen A KA Department of Wildlife and Fisheries Sciences, Texas A&M University, 454 Throckmorton St, College Station, TX, - - 2014
Little is known about the tactics northern elephant seals (NES) use to capture prey due to the difficulties in observing these animals underwater. NES forage on vertically migrating prey at depths >500 m during day and at night where light levels are negligible. Although NES have increased visual sensitivity in ...
Martens Andy A University of Canterbury, Christchurch, New - - 2014
Highly lethal terrorist attacks, which we define as those killing 21 or more people, account for 50% of the total number of people killed in all terrorist attacks combined, yet comprise only 3.5% of terrorist attacks. Given the disproportionate influence of these incidents, uncovering systematic patterns in attacks that precede ...
Liu Yunxia - - 2013
Hand, foot, and mouth disease (HFMD) has caused major public health concerns worldwide, and has become one of the leading causes of children death. China is the most serious epidemic area with a total of 3,419,149 reported cases just from 2008 to 2010, and its different geographic areas might have ...
Lichtenhan Jeffery T JT Massachusetts Eye & Ear Infirmary, Eaton-Peabody Laboratory of Auditory Physiology, Boston, MA 02114, USA. - - 2013
Presently available nonbehavioral methods to estimate auditory thresholds perform less well at frequencies below 1 kHz than at 1 kHz and above. For many uses, such as providing accurate infant hearing aid amplification for low-frequency vowels, an accurate nonbehavioral method to estimate low-frequency thresholds is needed. A novel technique was ...
Padmanaban Jeya J JP Research, Inc., Mountain View, - - 2013
There is evidence that underride events are undercounted by the Fatality Analysis Reporting System (FARS), a census of fatal crashes on public roads in the United States. This study's principal objective was to develop accurate fatality estimates for side underride crashes involving "combination trucks" and light vehicles. Police reports from ...
Tang Julian W JW Department of Laboratory Medicine, National University Hospital, Singapore. - - 2013
Hospital isolation rooms are vital for the containment (when under negative pressure) of patients with, or the protection (when under positive pressure) of patients, from airborne infectious agents. Such facilities were essential for the management of highly contagious patients during the 2003 severe acute respiratory syndrome (SARS) outbreaks and the ...
Choi Cheol Young - - 2012
The present study aimed to test starvation-induced oxidative stress in the cinnamon clownfish Amphiprion melanopus illuminated by light-emitting diodes (LEDs): red (peak at 630nm), green (peak at 530nm), and blue (peak at 450nm) within a visible light. We investigated the oxidative stress induced by starvation for 12days during illumination with ...
Bergevin Christopher - - 2012
Otoacoustic emissions (sound emitted from the ear) allow cochlear function to be probed noninvasively. The emissions evoked by pure tones, known as stimulus-frequency emissions (SFOAEs), have been shown to provide reliable estimates of peripheral frequency tuning in a variety of mammalian and non-mammalian species. Here, we apply the same methodology ...
Lomber Stephen - - 2012
Within extrastriate visual cortex of humans, monkeys and cats, individual cortical areas are specialized for spatial or motion processing. In cat auditory cortex, four regions have been identified to be critical for accurately determining the spatial location of an acoustic stimulus. The purpose of the present investigation was to determine ...
Schallek Jesse B JB Department of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York, USA. - - 2012
To examine the impact of reduced inner retinal function and breed on intrinsic optical signals in cats. Retinal intrinsic optical signals were recorded from anesthetized cats with a modified fundus camera. Near infrared light (NIR, 700-900 nm) was used to illuminate the retina while a charge-coupled device (CCD) camera captured ...
Ramsier Marissa A - - 2012
Few mammals-cetaceans, domestic cats and select bats and rodents-can send and receive vocal signals contained within the ultrasonic domain, or pure ultrasound (greater than 20 kHz). Here, we use the auditory brainstem response (ABR) method to demonstrate that a species of nocturnal primate, the Philippine tarsier (Tarsius syrichta), has a ...
Wang J - - 2012
The purpose of this study was to clarify stimulus pulse parameters effective to elicit behaviors of cats trained to detect electric pulse stimuli through chronically implanted electrodes in the primary auditory cortex. One or two pulse parameters were systematically shifted from the standard stimulus consisting of constant-current pulses of amplitude ...
Zhong Hui - - 2012
Adult cats with a complete spinal cord transection at T12-T13 can relearn over a period of days-to-weeks how to generate full weight-bearing stepping on a treadmill or standing ability if trained specifically for that task. In the present study, we assessed short-term (milliseconds to minutes) adaptations by repetitively imposing a ...
Li Xu - - 2011
Cryptochromes are blue-light receptors mediating various light responses in plants and animals. The photochemical mechanism of cryptochromes is not well understood. It has been proposed that photoactivation of cryptochromes involves the blue-light-dependent photoreduction of flavin adenine dinucleotide via the electron transport chain composed of three evolutionarily conserved tryptophan residues known ...
Friedburg Christoph - - 2011
To provide an up to 14-year overview of the early ocular phenotype in siblings with a homozygous p.G461R mutation in the KCNV2 gene. Two brothers and their sister were followed-up clinically from ages 5 years, 4 years, and 2 months, respectively, including complete ophthalmological examinations. Goldmann visual fields, two-color-threshold (2CT) ...
Sokolova Vladyslava - - 2012
Phytochromes are the red/far-red photoreceptors in higher plants. Among them, phytochrome A (PHYA) is responsible for the far-red high-irradiance response and for the perception of very low amounts of light, initiating the very-low-fluence response. Here, we report a detailed physiological and molecular characterization of the phyA-5 mutant of Arabidopsis (Arabidopsis ...
Kondoh Masato - - 2011
Cryptochromes (CRYs) are widespread flavoproteins with homology to photolyases (PHRs), a class of blue-light-activated DNA repair enzymes. Unlike PHRs, both plant and animal CRYs have a C-terminal domain. This cryptochrome C-terminal (CCT) domain mediates interactions with other proteins, while the PHR-like domain converts light energy into a signal via reduction ...
Burghardt Thomas P TP Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, United States. - - 2011
Myosin motors transduce ATP free energy into mechanical work. Transduction models allocate specific functions to motor structural domains beginning with ATP hydrolysis in the active site and ending in a lever-arm rotating power-stroke. Myosin light chains, regulatory (RLC) and essential (ELC), bind IQ-domains on the lever-arm and track its movement. ...
Adamczyk Andrew J - - 2011
The proposal that enzymatic catalysis is due to conformational fluctuations has been previously promoted by means of indirect considerations. However, recent works have focused on cases where the relevant motions have components toward distinct conformational regions, whose population could be manipulated by mutations. In particular, a recent work has claimed ...
Tierney Simon M - - 2012
Most bees rely on flowering plants and hence are diurnal foragers. From this ancestral state, dim-light foraging in bees requires significant adaptations to a new photic environment. We used DNA sequences to evaluate the phylogenetic history of the most diverse clade of Apoidea that is adapted to dim-light environments (Augochlorini: ...
Karlstam Lena - - 2011
Objective  To describe a slowly progressive retinopathy (SPR) in Shetland Sheepdogs. Animals  Forty adult Shetlands Sheepdogs with ophthalmoscopic signs of SPR and six normal Shetland Sheepdogs were included in the study. Procedure  Ophthalmic examination including slit-lamp biomicroscopy and ophthalmoscopy was performed in all dogs. Electroretinograms and obstacle course-test were performed ...
Lahiri Mayukh - - 2011
It was shown not long ago that complete spatial coherence of light at a pair of points in the space-time domain may be interpreted as a manifestation of so-called "statistical similarity" between the fluctuating field at the two points. In this Letter, we consider complete spatial coherence at a pair ...
Yuan Hua H Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, - - 2011
PixD (Slr1694) is a BLUF (blue-light-using FAD) photoreceptor used by the cyanobacterium Synechocystis sp. PCC6803 to control phototaxis toward blue light. In this study, we probe the involvement of a conserved Tyr8-Gln50-Met93 triad in promoting an output signal upon blue light excitation of the bound flavin. Analysis of acrylamide quenching ...
Liu Jian - - 2011
Rhodopsin has developed mechanisms to optimize its sensitivity to light by suppressing dark noise and enhancing quantum yield. We propose that an intramolecular hydrogen-bonding network formed by ∼20 water molecules, the hydrophilic residues, and peptide backbones in the transmembrane region is essential to restrain thermal isomerization, the source of dark ...
Caporale Natalia N Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720-2020, - - 2011
Inherited retinal degeneration results from many different mutations in either photoreceptor-specific or nonphotoreceptor-specific genes. However, nearly all mutations lead to a common blinding phenotype that initiates with rod cell death, followed by loss of cones. In most retinal degenerations, other retinal neuron cell types survive for long periods after blindness ...
Wang Xing - - 2011
In Synechocystis sp. PCC 6803, the loop domain (aa 1-70) of the phycobilisome core-membrane linker, L(CM), was found to interact with the glycosyl transferase homolog, Sll1466. Growth of a Sll1466 knock-out mutant was slightly faster in low light, but strongly inhibited in high light; the phenotype is discussed in relation ...
Nazari Mahboobeh - - 2011
The bioluminescence reaction, which uses luciferin, Mg(2+)-ATP and molecular oxygen to yield an electronically excited oxyluciferin, is carried out by luciferase and emits visible light. The bioluminescence color of firefly luciferases is determined by the luciferase structure and assay conditions. It is proposed that the stability of a protein can ...
Chen Min - - 2011
A limiting factor for photosynthetic organisms is their light-harvesting efficiency, that is the efficiency of their conversion of light energy to chemical energy. Small modifications or variations of chlorophylls allow photosynthetic organisms to harvest sunlight at different wavelengths. Oxygenic photosynthetic organisms usually utilize only the visible portion of the solar ...
Johnson Matthew P - - 2011
Plants must regulate their use of absorbed light energy on a minute-by-minute basis to maximize the efficiency of photosynthesis and to protect photosystem II (PSII) reaction centers from photooxidative damage. The regulation of light harvesting involves the photoprotective dissipation of excess absorbed light energy in the light-harvesting antenna complexes (LHCs) ...
Chu Patrick Hw - - 2011
Purpose:  The present study investigated retinal adaptive responses in concert with the modulation of forward and backward adaptation induced by periodic global flashes using the global flash multifocal electroretinogram (mfERG). Methods:  Six normal subjects were recruited for global flash mfERG measurements, which consisted of 103 scaled hexagonal elements followed by ...
Förster Britta - - 2011
Leaves of avocado (Persea americana Mill.) that develop and persist in deep shade canopies have very low rates of photosynthesis but contain high concentrations of lutein epoxide (Lx) that are partially de-epoxidized to lutein (L) after one hour exposure to 120 to 350 µmol photons m-2 s-1 increasing the total ...
Oguchi Riichi - - 2011
• We studied how different color lights cause gradients of photoinhibition within a leaf, to attempt to resolve the controversy of whether photon absorption by chlorophyll or by manganese (Mn) is the primary cause of photoinhibition, as suggested by the excess-energy hypothesis or the two-step hypothesis, respectively. • Lincomycin-treated leaf ...
Niedzwiedzki Dariusz M - - 2011
A peripheral light-harvesting complex from the aerobic purple bacterium Roseobacter (R.) denitrificans was purified and its photophysical properties characterized. The complex contains two types of pigments, bacteriochlorophyll (BChl) a and the carotenoid (Car) spheroidenone and possesses unique spectroscopic properties. It appears to lack the B850 bacteriochlorophyll a Q(y) band that ...
Samoilova O P - - 2011
In this work, using a PAM-fluorimetry technique, we have compared effects of plant adaptation to the light or dark conditions on the kinetics of chlorophyll a fluorescence yield in Tradecantia leaves of several species (T. albiflora, T. fluminensis, T. navicularis, and T. sillamontana), which represent plants of different ecotypes. Two ...
Tang Kuo-Hsiang - - 2011
Chlorosomes, the peripheral light-harvesting antenna complex from green photosynthetic bacteria, are the largest and one of the most efficient light-harvesting antenna complexes found in nature. In contrast to other light-harvesting antennas, chlorosomes are constructed from more than 150 000 self-assembled bacteriochlorophylls (BChls) and contain relatively few proteins that play secondary roles. ...
Wang Xuewen X School of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, - - 2011
The shade avoidance syndrome (SAS) allows plants to anticipate and avoid shading by neighbouring plants by initiating an elongation growth response. The phytochrome photoreceptors are able to detect a reduction in the red:far red ratio in incident light, the result of selective absorption of red and blue wavelengths by proximal ...
Ohad Itzhak - - 2011
We briefly review the main mechanisms proposed for photodamage to photosystem II, at the donor and at the acceptor sides, and then discuss the mechanism whereby filamentous cyanobacteria inhabiting biological sand crusts such as Microcoleus sp. are able to avoid serious damage to their photosynthetic machinery. We show that the ...
Hughes Nicole M - - 2011
Leaf reddening during autumn in senescing, deciduous tree species has received widespread attention from the public and in the scientific literature, whereas leaf reddening in evergreen species during winter remains largely ignored. Winter reddening can be observed in evergreen herbs, shrubs, vines and trees in Mediterranean, temperate, alpine, and arctic ...
Dankov Kolyo G - - 2011
Pulse-amplitude-modulated (PAM) chlorophyll fluorescence and photosynthetic oxygen evolution were used to investigate the role of the different amount and organization of light-harvesting complexes of photosystem II (LHCII) in four pea species on the susceptibility of the photosynthetic apparatus to high-light treatment. In this work we analyzed the thylakoid membrane lipid ...
Inoue-Kashino Natsuko - - 2011
The psb30 (ycf12) gene is conserved in a wide variety of oxygenic-photosynthetic organisms except angiosperms and some marine cyanobacteria. Psb30 protein is found in cyanobacterial photosystem II (PSII) core complexes and is dispensable for PSII structure and function. The most recent three-dimensional structure of cyanobacterial PSII core complex has revealed ...
Conde-Álvarez Rafael M - - 2011
We have studied the plasticity of the photosynthetic apparatus in the endangered aquatic macrophyte Althenia orientalis to the gradient of light availability within its meadow canopy. We determined diurnal change in situ irradiance, light quality, in vivo chlorophyll a fluorescence, ex situ oxygen evolution rates, respiration rate and pigment concentration. ...
Tomo Tatsuya - - 2011
This mini review presents current topics of discussion about photosystem (PS) I and PS II of photosynthesis in the Acaryochloris marina. A. marina is a photosynthetic cyanobacterium in which chlorophyll (Chl) d is the major antenna pigment (>95%). However, Chl a is always present in a few percent. Chl d ...
Hartz Aaron J - - 2011
ABSTRACT. Expressed rhodopsins were detected by proteomic analysis in an investigation of potential signal receptors in the cell membrane of the marine heterotrophic dinoflagellate Oxyrrhis marina (CCMP604). We inferred these to be sensory rhodopsins, a type of G-protein-coupled receptor trans-membrane signaling molecule. Because phototactic behavior based on sensory rhodopsins has ...
Nefissi Rim - - 2011
The photoperiodic response is one of the adaptation mechanisms to seasonal changes of lengths of day and night. The circadian clock plays pivotal roles in this process. In Arabidopsis, LHY, CCA1, ELF3, and other clock proteins play major roles in maintaining circadian rhythms. lhy;cca1 double mutants with severe defects in ...
Vass Imre - - 2011
Light induced damage of the photosynthetic apparatus is an important and complex phenomenon, which affects primarily the Photosystem II complex. Here I summarize the current state of understanding, which concerns the role of charge recombination reactions in photodamage and photoprotection. The main mechanism of photodamage induced by visible light appears ...
Oguchi Riichi - - 2011
Photosystem II (PS II) is photoinactivated during photosynthesis, requiring repair to maintain full function during the day. What is the mechanism(s) of the initial events that lead to photoinactivation of PS II? Two hypotheses have been put forward. The excess-energyhypothesis states that excess energy absorbed by Chl, neither utilized in ...
Fetterman J Gregor - - 2011
Pigeons pecked on three keys, responses to one of which could be reinforced after 3 flashes of the houselight, to a second key after 6, and to a third key after 12. The flashes were arranged according to variable-interval schedules. Response allocation among the keys was a function of the ...
Rakhimberdieva Marina G - - 2011
Blue light induced quenching in a Synechocystis sp. PCC 6803 strain lacking both photosystems is only related to allophycocyanin fluorescence. A fivefold decrease in the fluorescence level in two bands near 660 and 680nm is attributed to different allophycocyanin forms in the phycobilisome core. Some low-heat sensitive component inactivated at ...
Hart Nathan Scott - - 2011
Sharks are apex predators, and their evolutionary success is in part due to an impressive array of sensory systems, including vision. The eyes of sharks are well developed and function over a wide range of light levels. However, whilst close relatives of the sharks-the rays and chimaeras-are known to have ...
Thangaraj Balakumar - - 2011
Photosystem I-light harvesting complex I (PSI-LHCI) was isolated from the thermoacidophilic red alga Galdieria sulphuraria, and its structure, composition, and light-harvesting function were characterized by electron microscopy, mass spectrometry, and ultrafast optical spectroscopy. The results show that Galdieria PSI is a monomer with core features similar to those of PSI ...
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