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Bloch Guy G Department of Ecology, Evolution, and Behavior, The Hebrew University of Jerusalem, Jerusalem, - - 2013
Daily rhythms of physiology and behaviour are governed by an endogenous timekeeping mechanism (a circadian 'clock'). The alternation of environmental light and darkness synchronizes (entrains) these rhythms to the natural day-night cycle, and underlying mechanisms have been investigated using singly housed animals in the laboratory. But, most species ordinarily would ...
Vinayak Pooja - - 2013
Drosophila melanogaster shows exquisite light sensitivity for modulation of circadian functions in vivo, yet the activities of the Drosophila circadian photopigment cryptochrome (CRY) have only been observed at high light levels. We studied intensity/duration parameters for light pulse induced circadian phase shifts under dim light conditions in vivo. Flies show ...
Vargas Esteban - - 2013
This article attempts to clarify Francisco Varela’s proposal of a neurophenomenology of time consciousness in the light of distinctions based on the philosophical literature of phenomenology and recent advances of neurobiology. The analysis is carried out considering three aspects. In the first of them, we discuss the phenomenological aspect of ...
Schulze Julia - - 2013
Light entrainment pathways synchronize the circadian clock of almost all species of the animal and plant kingdom to the daily light dark cycle. In the Madeira cockroach Rhyparobia (Leucophaea) maderae, the circadian clock is located in the accessory medulla of the brain's optic lobes. The clock has abundant neuropeptides with ...
Hsiao Fan-Chi - - 2013
This study characterizes the different response patterns of sleep and wakefulness to short light-dark cycles in albino mice and examines whether retinal degeneration resulting from prolonged bright light treatment and/or rd/rd mutation alters such response patterns. Eight young male ICR mice with normal eyes, 7 young male rd/rd FVB mice, ...
Melo Paula - - 2013
Synchronized state of activity and rest might be attained by mechanisms of entrainment and masking. Most zeitgebers not only act to entrain but also to mask circadian rhythms. Although the light-dark (LD) cycle is the main zeitgeber of circadian rhythms in marmosets, social cues can act as weaker zeitgebers. Evidence ...
Fifel Karim - - 2013
In addition to the hallmark motor disorders in Parkinson's disease (PD) patients, nonmotor symptoms have attracted increasing attention. Among the nonmotor symptoms, sleep disturbances and cognitive deficits are frequently reported and contribute to a decrease in the quality of life. The pathophysiology of cognitive and sleep-wake abnormalities in PD is ...
de Boer Betteco J - - 2013
In the present study, we examined whether coupling influences resulting from unintended afference-based phase entrainment are affected by movement amplitude as such or by the amplitude relation between the limbs. We assessed entrainment strength by studying how passive movements of the contralateral hand influenced unimanual coordination with a metronome. Results ...
Dominoni D M DM Department of Migration and Immuno-ecology, Max Planck Institute for Ornithology, Radolfzell 78479, Germany. - - 2013
To keep pace with progressing urbanization organisms must cope with extensive habitat change. Anthropogenic light and noise have modified differences between day and night, and may thereby interfere with circadian clocks. Urbanized species, such as birds, are known to advance their activity to early morning and night hours. We hypothesized ...
Kumar Kanhaiya - - 2013
Light is one of the important parameters for the growth of photosynthetic microorganisms. In algal photobioreactors, pigmentation of algal cells has additional shading effect which reduces light penetration. Information on the local light intensity inside the photobioreactor is helpful for its efficient designs. Image analysis is based on trichromatic theory ...
van Dijk W - - 2013
To promote active participation of neurological patients during robotic gait training, controllers, such as "assist as needed" or "cooperative control", are suggested. Apart from providing support, these controllers also require that the robot should be capable of resembling natural, unsupported, walking. This means that they should have a transparent mode, ...
Kim M J - - 2013
A study was conducted to investigate the effect of different monochromatic lights on growth performance and hematological response of growing broiler chickens. A total of 360 one-day-old broiler chicks were randomly divided into 6 lighting treatments, which were replicated 6 times with 10 chicks in each replicate. Six light treatments ...
Li Yue - - 2013
Phase resetting by light is an important feature of circadian rhythms, and the current Drosophila model focuses on light-mediated degradation of the clock protein TIMELESS (TIM). PERIOD (PER) is the binding partner of TIM and a major repressor of the molecular clock, but direct evidence of PER in phase resetting ...
Muraro Nara I - - 2013
Over the years it has become crystal clear that a variety of processes encode time of day information, ranging from gene expression, protein stability, or subcellular localization of key proteins, to the fine tuning of network properties and modulation of input signals, ultimately ensuring that physiology and behavior are properly ...
Martín-Robles Agueda J - - 2013
Studies on the developmental onset of the teleost circadian clock have been carried out in zebrafish and, recently, in rainbow trout and Senegalese sole, where rhythms of clock gene expression entrained by light-dark (LD) cycles have been reported from the first days post fertilization. However, investigations of molecular clock rhythms ...
Carazo I - - 2013
The present study aimed to determine a non-invasive nocturnal lighting system for the behavioural observation of a highly light sensitive species, Senegalese sole (Solea senegalensis). Locomotor activity, four types of behaviour and plasma melatonin were analysed in groups of 12 adult Senegalese sole (Solea senegalensis) reared in captivity and held ...
Saper Clifford B CB Department of Neurology, Division of Sleep Medicine, and Program in Neuroscience, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States. Electronic address: - - 2013
It has been known since the 1970s that the suprachiasmatic nucleus (SCN) is the brain's main biological clock, and since the 1990s that it uses a genetic clock based on transcriptional-translational loops to tell time. However, the recent demonstration that many other cells in the brain and the body also ...
Prendergast Brian J BJ Department of Psychology, University of Chicago, Chicago, IL 60637, USA. - - 2013
Studies of rats and voles suggest that distinct pathways emanating from the anterior hypothalamic-retrochiasmatic area and the mediobasal hypothalamic arcuate nucleus independently generate ultradian rhythms (URs) in hormone secretion and behavior. We evaluated the hypothesis that destruction of arcuate nucleus (ARC) neurons, in concert with dampening of suprachiasmatic nucleus (SCN) ...
Vera L M - - 2013
Daily light and feeding cycles act as powerful synchronizers of circadian rhythmicity. Ultimately, these external cues entrain the expression of clock genes, which generate daily rhythmic behavioral and physiological responses in vertebrates. In the present study, we investigated clock genes in a marine teleost (gilthead sea bream). Partial cDNA sequences ...
Erzberger A A Department of Biological Physics, Max Planck Institute for the Physics of Complex Systems, Dresden, Germany. - - 2013
Circadian clocks are internal timekeepers present in almost all organisms. Driven by a genetic network of highly conserved structure, they generate self-sustained oscillations that entrain to periodic external signals such as the 24 h light-dark cycle. Vertebrates possess multiple, functionally overlapping homologues of the core clock genes. Furthermore, vertebrate clocks ...
Stanley David A DA Department of Biomedical Engineering, University of Florida, Gainesville, Florida, - - 2013
For over a century epileptic seizures have been known to cluster at specific times of the day. Recent studies have suggested that the circadian regulatory system may become permanently altered in epilepsy, but little is known about how this affects neural activity and the daily pattern of seizures. To investigate, ...
Smarr Benjamin L BL Department of Biology and Program of Neurobiology and Behavior, University of Washington, Seattle, WA 98195, - - 2013
The circadian system temporally organizes physiology and behavior throughout the 24-h day. At the core of this organization lies a network of multiple circadian oscillators located within the central nervous system as well as in virtually every peripheral organ. These oscillators define a 24-h temporal landscape of mutually interacting circadian ...
De Joydeep J Behavioural Neurogenetics Laboratory, Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, - - 2013
Studies on circadian entrainment have traditionally been performed under controlled laboratory conditions. Although these studies have served the purpose of providing a broad framework for our understanding of regulation of rhythmic behaviors under cyclic conditions, they do not reveal how organisms keep time in nature. Although a few recent studies ...
Ruiz Jesús - - 2013
OBJECTIVES: Filtering the cardiopulmonary resuscitation (CPR) artifact has been a major approach to minimizing interruptions to CPR for rhythm analysis. However, the effects of these filters on interruptions to CPR have not been evaluated. This study presents the first methodology for directly quantifying the effects of filtering on the uninterrupted ...
Leloup Jean-Christophe - - 2013
Advancing or delaying the light-dark (LD) cycle perturbs the circadian clock, which eventually recovers its original phase with respect to the new LD cycle. Readjustment of the clock occurs by shifting its phase in the same (orthodromic re-entrainment) or opposite direction (antidromic re-entrainment) as the shift in the LD cycle. ...
Yeang Hoong-Yeet - - 2013
In photoperiodic flowering, long-day (LD) plants are induced to flower seasonally when the daylight hours are long, whereas flowering in short-day (SD) plants is promoted under short photoperiods. According to the widely accepted external coincidence model, flowering occurs in LD Arabidopsis when the circadian rhythm of the gene CONSTANS (CO) ...
Ma Peijun - - 2013
Circadian clocks are found in a wide variety of organisms from cyanobacteria to mammals. Many believe that the circadian clock system evolved as an adaption to the daily cycles in light and temperature driven by the rotation of the earth. Studies on the cyanobacterium, Synechococcus elongatus PCC 7942, have confirmed ...
Sukovich Jonathan R - - 2013
Previous investigations of the temporal and spatial evolution of single bubble sonoluminescence (SBSL) have shown events to last on the order of tens to hundreds of picoseconds with spatial extents of less than 1 μm. Here we present observations of the temporal and spatial evolution of laser-nucleated SBSL events in ...
Nakamura Shizuka - - 2013
In this author's previous study [Nakamura, J. Acoust. Soc. Am. 131(4, Pt. 2), 3347 (2012)] on the acoustical analysis of the duration structure of rhythm in English speech observed in short sentences uttered by native speakers, the durations of the following rhythm unit showed the smallest variance among native speakers: ...
Chung Younah - - 2013
Korean has not been unanimously classified for rhythm class, and it lacks stress. Thus, it does not fit into views that rhythm rests on alternations of metrical strength. The goal was to examine what, if any, elements are used in Korean for rhythm purposes. It was hypothesized that the onsets ...
Tomina Yusuke - - 2013
Animals generally exhibit circadian rhythms of locomotor activity. They initiate locomotor behavior not only reflexively in response to external stimuli but also spontaneously in the absence of any specific stimulus. The neuronal mechanisms underlying circadian locomotor activity can, therefore, be based on the rhythmic changes in either reflexive efficacy or ...
Reitzel Adam M AM Department of Biology, University of North Carolina at Charlotte, Charlotte, NC 28223, USA. - - 2013
The circadian clock is a molecular network that translates predictable environmental signals, such as light levels, into organismal responses, including behavior and physiology. Regular oscillations of the molecular components of the clock enable individuals to anticipate regularly fluctuating environmental conditions. Cnidarians play important roles in benthic and pelagic marine environments ...
Kommedal Siri - - 2013
The circadian clock in the chicken pineal model develops before hatching, at around the 17th embryonic day (ED17). By this stage, it runs in synchrony with environmental cues. To address if phase resetting mechanisms are comparable to those of post-hatched chicken, we investigated ED19 stage chicken embryos under 12 hours ...
Valdez Diego J - - 2013
All organisms have evolved photodetection systems to synchronize their physiology and behavior with the external light-dark (LD) cycles. In nonmammalian vertebrates, the retina, the pineal organ, and the deep brain can be photoreceptive. Inner retinal photoreceptors transmit photic information to the brain and regulate diverse nonvisual tasks. We previously reported ...
Richards Jacob J Department of Medicine, University of Florida, Gainesville, FL, - - 2013
It has been well established that the circadian clock plays a crucial role in the regulation of almost every physiological process. It also plays a critical role in pathophysiological states including those of obesity and diabetes. Recent evidence has highlighted the potential for targeting the circadian clock as a potential ...
Ono Daisuke - - 2013
Cryptochrome (Cry) 1 and Cry2 are regarded as critical components for circadian rhythm generation in mammals. Nevertheless, cultured suprachiasmatic nucleus (SCN) of neonatal Cry double deficient (Cry1(-/-)/Cry2(-/-)) mice exhibit circadian rhythms that damp out in several cycles. Here, by combining bioluminescence imaging of Per1-luc and PER2::LUC with multielectrode recording, we ...
Egli Martin M Department of Biochemistry, Vanderbilt University, School of Medicine, Nashville, TN 37232, USA. Electronic address: - - 2013
The biochemical basis of circadian timekeeping is best characterized in cyanobacteria. The structures of its key molecular players, KaiA, KaiB, and KaiC are known and these proteins can reconstitute a remarkable circadian oscillation in a test tube. KaiC is rhythmically phosphorylated and its phospho-status is a marker of circadian phase ...
Zhu Yong Y School of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA. - - 2013
Human circadian rhythms are regulated by the interplay between circadian genes and environmental stimuli. The influence of altered sleep-wake schedules or light on human circadian gene expression patterns is not well characterized. Twenty-one young adults were asked to keep to their usual sleep schedules and two blood samples were drawn ...
Bolouri Moghaddam Mohammad Reza - - 2013
All organisms have an internal timing mechanism, termed the circadian clock, to anticipate the light/dark cycle. The clock, with an oscillating rhythm that approximates 24h, is a rather robust system persisting to a great extent in continuous light and dark. It is widely accepted that plant growth and development are ...
Cook Peter - - 2013
Is the ability to entrain motor activity to a rhythmic auditory stimulus, that is "keep a beat," dependent on neural adaptations supporting vocal mimicry? That is the premise of the vocal learning and synchronization hypothesis, recently advanced to explain the basis of this behavior (A. Patel, 2006, Musical Rhythm, Linguistic ...
Golombek Diego A - - 2013
Circadian rhythms are endogenous and need to be continuously entrained (synchronized) with the environment. Entrainment includes both coupling internal oscillators to external periodic changes as well as synchrony between the central clock and peripheral oscillators, which have been shown to exhibit different phases and resynchronization speed. Temporal desynchronization induces diverse ...
Dodd Antony N AN School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK, - - 2014
Correct circadian regulation increases plant productivity, and photosynthesis is circadian-regulated. Here, we discuss the regulatory basis for the circadian control of photosynthesis. We discuss candidate mechanisms underpinning circadian oscillations of light harvesting and consider how the circadian clock modulates CO2 fixation by Rubisco. We show that new techniques may provide ...
Menaker Michael - - 2013
The suprachiasmatic nucleus of the hypothalamus and at least two other unidentified central pacemakers regulate the temporal structure of a circadian network that involves almost every organ in the body. Phase control is central to the efficient function of this system. Individual circadian oscillators in tissues and organs in the ...
Fukuda Hirokazu - - 2013
Plant circadian systems are composed of a large number of self-sustained cellular circadian oscillators. Although the light-dark signal in the natural environment is known to be the most powerful Zeitgeber for the entrainment of cellular oscillators, its effect is too strong to control the plant rhythm into various forms of ...
Shimmura Tsuyoshi - - 2013
Crowing of roosters is described by onomatopoetic terms such as 'cock-a-doodle-doo' (English), 'ki-ke-ri-ki' (German), and 'ko-ke-kok-koh' (Japanese). Rooster crowing is a symbol of the break of dawn in many countries. Indeed, crowing is frequently observed in the morning [1]. However, people also notice that crowing is sometimes observed at other ...
El Allali Khalid - - 2013
The LD cycle is known to be the major cue to synchronize the circadian clock. In arid areas, the camel is exposed to extreme environmental conditions. Since wide oscillations of ambient temperature (Ta) are a major factor, we wondered whether cyclic Ta might contribute to synchronization of rhythms. The rhythm ...
Bedrosian Tracy A - - 2013
Humans and other organisms have adapted to a 24-h solar cycle in response to life on Earth. The rotation of the planet on its axis and its revolution around the sun cause predictable daily and seasonal patterns in day length. In order to successfully anticipate and adapt to these patterns ...
Ozturk Nuri - - 2013
Cryptochrome (CRY) is the primary circadian photoreceptor in Drosophila. It resets the circadian clock by promoting light-induced degradation of the clock proteins Timeless and Period, as well as its own proteolysis. The E3 ligases that ubiquitylate Timeless and Period before degradation are known and it is known that Drosophila (d) ...
Müller Werner E G - - 2013
In all eukaryotes, the 24-h periodicity in the environment contributed to the evolution of the molecular circadian clock. We studied some elements of a postulated circadian clock circuit in the lowest metazoans, the siliceous sponges. First, we identified in the demosponge Suberites domuncula the enzyme luciferase that generates photons. Then ...
Wojno Adam P - - 2013
One-time gene therapy resulted in multiyear visual improvement, and new approaches were used to evaluate effects on retinal structure.
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