Search Results
Results 1 - 50 of 898
1 2 3 4 5 6 7 8 9 10 >
Greb Lutz - - 2014
: Chiral N-alkyl imines undergo unidirectional rotation in-duced by light and heat, thus providing a new class of mo-lecular motors. Depending on the conformational flexibility of the stator part (the carbonyl residue) and the nitrogen inversion barrier of the rotor part (the amine residue) in the molecule, the operation mode ...
Chen Jiawen J Centre for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747AG Groningen, The Netherlands. - - 2014
In order to improve the rotary motion of surface assembled light-driven molecular motors, tetra-acid-functionalized motors were bound to an amine-coated quartz surface without prior activation of the acid groups. In contrast to earlier bipodal motors, the tetravalent motor showed no significant reduction in the rotation speed when attached to a ...
De Oliveira Ana Luísa Botta Martins AL Department of Social Dentistry, Araraquara School of Dentistry, University of São Paulo State, São Paulo, - - 2014
Composite resin is a dental material susceptible to color change over time which limits the longevity of restorations made with this material. The influence of light curing units and different fluoride mouthrinses on superficial morphology and color stability of a nanofilled composite resin was evaluated. Specimens (N = 150) were prepared and ...
Paulsen Morten T MT Nofima AS, Osloveien 1, Pb210, 1431 Ås, Norway; Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, - - 2014
The aim of this study was to determine the effects of different salt substitutes on the sensory perception of sausages. TDS was used to explore the temporal perception of the samples and DA was used as a reference method. Grill-style sausages with different levels of salt reduction combined with different ...
Mahapatra Ajit Kumar - - 2013
A new BODIPY-azaindole based fluorescent sensor was designed and synthesized as a new colorimetric and ratiometric fluorescent chemosensor for fluoride. The binding and sensing abilities of sensor towards various anions were studied by absorption, emission and (1)H NMR titration spectroscopies. The spectral responses of to fluoride in acetonitrile-water were studied: ...
Souza Joyce - - 2013
Trypsin and bile salts have been identified as important triggers for excystation of Echinostoma metacercariae. Although excystation in trematodes is a well-known phenomenon, some morphological developmental changes remain to be elucidated. In order to gain further insight into the in vitro development of metacercariae, we assayed different cultivating conditions: 0.5% ...
Okamoto Hideyuki - - 2013
Various Yb<sup>2+</sup>-containing fluoride glasses melting under a reductive atmosphere were prepared. The brightest white light emission was observed for an AlF<sub>3</sub>-based fluoride glass not containing Hf or Zr. The largest full width at half maximum of the white emission spectra was 202 nm. In addition, incorporation of chloride into the ...
da Silva Barbosa Patricia - - 2013
Abstract Objective: The aim of this study was to assess the effect of low-intensity infrared laser light (λ=810 nm, 100 mW/cm(2), 90 sec, 4.47 J/cm(2), 9 J) with or without indocyanine green cream fluorinated or not fluorinated, using Knoop surface microhardness analysis. Background data: Lasers can be used as tools for the prevention of ...
Ivanoff Chris S - - 2013
To compare the deposition of fluoride particles into bovine enamel by diffusion (n = 20); dielectrophoresis (DEP) at 10 Hz and 5000 Hz (n = 10); and DEP (10 Hz and 5000 Hz) combined with AC electroosmosis (ACEO) at 400 Hz (DEP/ACE) (n = 10). Fluoride particle movements induced at ...
Singh Shailendra P - - 2013
Fremyella diplosiphon is a freshwater cyanobacterium that exhibits complementary chromatic adaptation (CCA), which allows the organism to alter its pigmentation and cellular morphology to maximally harvest available green light (GL) and red light (RL) at different depth levels in its aquatic ecosystem. We tested the effect of salinity on CCA-associated ...
Timar-Gabor Alida - - 2013
Thermoluminescence (TL) and optically stimulated luminescence (OSL) in the UV (270-370 nm) spectral region have been investigated for five types of table salt (NaCl) available in Romanian supermarkets with a view to applying them in retrospective dosimetry. The salt samples gave bright TL signals with two main peaks at ∼100°C ...
Tyystjärvi Taina - - 2013
Sigma factors of RNA polymerase recognize promoters and have a central role in controlling transcription initiation and acclimation to changing environmental conditions. The cyanobacterium Synechocystis sp. PCC 6803 encodes four non-essential group 2 sigma factors, SigB, SigC, SigD and SigE that closely resemble the essential SigA factor. Three out of ...
Nguyen Thi-Thanh-Tam - - 2012
Light switch: A dendronized salt exhibiting photoswitchable conductivity was designed and synthesized. The salt consists of tetrabutylammonium cations and large, rigidly dendronized borate anions, each bearing eight photo-responsive azobenzene moieties. The conductivity of solutions of this salt can be reversibly switched by irradiation, owing to light-induced changes in the overall ...
Karadeniz Ersan I - - 2012
Abstract Objective: To evaluate the null hypothesis that fluoride intake via drinking water has no effect on orthodontic root resorption in humans after orthodontic force application for 4 weeks and 12 weeks of retention. Materials and Methods: Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected ...
Zhao Guanjia - - 2012
A novel thin capsule motor has been described in this report. It utilizes the Marangoni effect for the solid capsule to run at water-oil interlayer, which has not been reported previously. Intrinsic and environment factors influencing the motion were investigated. It is also possible for the speed, direction and start/stop ...
Rabbah Jean-Pierre M - - 2012
BACKGROUND: Percutaneous edge-to-edge mitral valve (MV) repair is a potential therapeutic option for patients presenting with mitral regurgitation, who may not be suitable for surgery. We characterized the edge-to-edge repair forces in a posterior leaflet flail MV model to identify potential modes of mechanical failure. METHODS: Porcine MVs were evaluated ...
Sliker Levin J - - 2012
BACKGROUND: The state-of-the-art technology for gastrointestinal (GI) tract exploration is a capsule endoscope (CE). Capsule endoscopes are pill-sized devices that provide visual feedback of the GI tract as they move passively through the patient. These passive devices could benefit from a mobility system enabling maneuverability and controllability. Potential benefits of ...
Dube Henry - - 2012
A matter of light: Selective control over the assembly of two distinct encapsulation complexes in solution is achieved by using light of two wavelengths and heat. Guest exchange can be triggered in a sequential or parallel fashion, depending on the wavelength applied, and three combinations of encapsulation complexes are accessible. ...
Miteva Mariya - - 2012
BACKGROUND: Nonscarring alopecia differs from scarring alopecia on pathologic examination by the preservation of follicular units and lack of follicular dropout. However, long-standing cases of active nonscarring hair loss can show follicular dropout on pathologic examination and can be difficult to interpret. OBSERVATIONS: We describe a patient with nonscarring alopecia ...
Choo Heeyoung - - 2011
In a glance, the visual system can provide a summary of some kinds of information about objects in a scene. We explore how summary information about orientation is extracted and find that some representations of orientation are privileged over others. Participants judged the average orientation of either a set of ...
Tanaka Seiji - - 2011
This study re-examines the effects of environmental factors including substrate color, humidity, food quality, light intensity and temperature on the green-brown polyphenism, black patterning and background body color of solitarious (isolated-reared) nymphs of Schistocerca gregaria. All individuals reared in yellow-green or yellow containers became green morphs, whereas those reared in ...
Fairbanks Benjamin D - - 2011
Various techniques have been adopted to impart a biological responsiveness to synthetic hydrogels for the delivery of therapeutic agents as well as the study and manipulation of biological processes and tissue development. Such techniques and materials include polyelectrolyte gels that swell and deswell with changes in pH, thermosensitive gels that ...
Sinigaglia Corrado - - 2011
In the present article we discuss the relevance of the mirror mechanism for our sense of self and our sense of others. We argue that, by providing us with an understanding from the inside of actions, the mirror mechanism radically challenges the traditional view of the self and of the ...
Adelman Cahtia - - 2011
The permanent hearing loss following exposure to intense noise can be due either to mechanical structural damage (tearing) caused directly by the noise or to metabolic (biochemical) damage resulting from the elevated levels of free radicals released during transduction of the sound overstimulation. Drugs which depress active cochlear mechanics (e.g. ...
Klemuk Sarah A - - 2011
Vocal production requires active control of the respiratory system, larynx and vocal tract. Vocal sounds in mammals are produced by flow-induced vocal fold oscillation, which requires vocal fold tissue that can sustain the mechanical stress during phonation. Our understanding of the relationship between morphology and vocal function of vocal folds ...
Tanaka Junji - - 2011
This study evaluated the protective effects of purple rice ( Oryza sativa L.) bran extract (PRE) and its major anthocyanidins (cyanidin and peonidin) against light-induced retinal damage. In an in vitro experiment, cultured murine photoreceptor cells (661W) were damaged by a 24 h exposure to light. Viability of 661W after ...
Schorsch Stefan - - 2010
Lasers are common tools in the field of combustion diagnostics. In some respects, however, they have disadvantages. Therefore, there is a need for new light sources delivering radiation in the required wavelength regions with high stability and reliability at low cost. Light-emitting diodes (LED) in the near- and mid-infrared spectral ...
Pfeiffenberger Cory - - 2010
Adult behavioral assays have been used with great success in Drosophila melanogaster to identify circadian rhythm genes. In particular, the locomotor activity assay can identify altered behavior patterns over the course of several days in small populations, or even individual flies. Generally, circadian behavior is assayed during a period of ...
Roenneberg Till - - 2010
The traditional approaches to predict entrainment of circadian clocks by light are based on 2 concepts that were never successfully unified: the non-parametric approach assumes that entrainment occurs via discrete daily phase shifts while the parametric approach assumes that entrainment involves changes of the clock's velocity. Here the authors suggest ...
Rémi Jan - - 2010
The two major prerequisites for a functional circadian system are the generation of an internal day (circadian cycle) and adjusting its length-and phase-to that of the external day (zeitgeber cycle). The generation of circadian cycles can be observed in constant conditions where organisms show a self-sustained, free-running rhythm. Their expression ...
Ogeil Rowan P - - 2010
Ecstasy users report a number of adverse events following use including disturbed sleep. Previous research has suggested that MDMA affects the circadian system, however, the acute effects following a single, moderate dose have not been well characterised. The current study investigated how MDMA affected the circadian system, as measured by ...
Butler Matthew P - - 2011
Light is the principal cue that entrains the circadian timing system, but the threshold of entrainment and the relative contributions of the retinal photoreceptors-rods, cones and intrinsically photosensitive retinal ganglion cells-are not known. We measured thresholds of entrainment of wheel-running rhythms at three wavelengths, and compared these to thresholds of ...
Gannon Robert L - - 2011
Glutamate released from retinal ganglion cells conveys information about the daily light:dark cycle to master circadian pacemaker neurons within the suprachiasmatic nucleus that then synchronize internal circadian rhythms with the external day-length. Glutamate activation of ionotropic glutamate receptors in the suprachiasmatic nucleus is well established, but the function of the ...
Sadeghniiat-Haghighi Khosro - - 2011
About 20% of workers in industrialized countries are shift workers and more than half of them work on night or rotating shifts. Most night workers complain of sleepiness due to lack of adjustment of the circadian rhythm. In simulated night-work experiments, scheduled exposure to bright light has been shown to ...
Otalora Beatriz Baño - - 2010
Daily rhythms in different biochemical and hematological variables have been widely described in either diurnal or nocturnal species, but so far no studies in the rhythms of these variables have been conducted in a dual-phasing species such as the degus. The Octodon degus is a rodent that has the ability ...
Vivanco Pablo - - 2010
Octodon degus is a primarily diurnal rodent that presents great variation in its circadian chronotypes due to the interaction between two phase angles of entrainment, diurnal and nocturnal, and the graded masking effects of environmental light and temperature. The aim of this study was to test whether the circadian system ...
García Rafael A - - 2010
The 11-year activity cycle of the Sun is a consequence of a dynamo process occurring beneath its surface. We analyzed photometric data obtained by the CoRoT space mission, showing solarlike oscillations in the star HD49933, for signatures of stellar magnetic activity. Asteroseismic measurements of global changes in the oscillation frequencies ...
Vivanco Pablo - - 2010
There are two main processes involved in the expression of circadian rhythmicity: entrainment and masking. Whereas the first operates via the central pacemaker to anticipate predictable environmental conditions, masking (mainly induced by light) functions as a direct modulator of the circadian output signal induced by nonpredictable events. The Chilean rodent ...
López-Olmeda Jose F - - 2010
Food provided on a periodic basis can act as a potent synchronizer, being a stronger zeitgeber than light for peripheral oscillators in mammals. In fish, however, little is known about the influence of feeding time on the circadian pacemaker and the relationship between central and peripheral oscillators. The aim of ...
El Moussaouiti Rachid - - 2010
The phase and period responses to short light pulses were studied in the jerboa, a seasonal, hibernating, nocturnal rodent from the Atlas region in Morocco. The jerboa, which is a saltatory species, showed precise activity onsets and offsets under a light-dark (LD) cycle using infrared captors to record locomotor activity. ...
Chiesa Juan José - - 2010
The temporal distribution of behavioral programs throughout the 24-h day, known as temporal niche of a species, is determined by ecological factors that directly affect the adaptive value of the timing of specific behaviors. Temporal niche switching has been described in several species and is likely adaptive in habitats where ...
Kallingal George J - - 2010
Brief light pulses or microinjection of gastrin-releasing peptide (GRP) into the third ventricle or near the suprachiasmatic nucleus (SCN) induce phase shifts of circadian rhythms during the subjective night. It has previously been reported that these effects are strongly influenced by the activation of N-methyl-d-aspartate (NMDA) receptors and the availability ...
Gander P E - - 2010
We studied the effect of auditory training on the 40-Hz auditory steady-state response (ASSR) known to localize tonotopically to the region of primary auditory cortex (A1). The stimulus procedure was designed to minimize competitive interactions among frequency representations in A1 and delivered target events at random times in a training ...
Zapka Manuela M AG Neurosensorik, Institut für Biologie und Umweltwissenschaften, University of Oldenburg, D-26111 Oldenburg, - - 2010
Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, ...
Hammer Steven B SB Department of Biological Sciences, Kent State University, Kent, Ohio 44242, - - 2010
Alcohol abuse leads to marked disruptions of circadian rhythms, and these disturbances in themselves can increase the drive to drink. Circadian clock timing is regulated by light, as well as by nonphotic influences such as food, social interactions, and wheel running. We previously reported that alcohol markedly disrupts photic and ...
Lone Shahnaz Rahman - - 2010
Circadian clocks provide adaptive advantage to their owners by timing their behavioural and physiological processes in accordance with the external environment. Here we report the results of our study aimed at investigating the effect of the interaction between circadian timing system and environmental light/dark (LD) cycles on pre-adult development time ...
Morin Lawrence P LP Department of Psychiatry, Stony Brook University Medical Center, Stony Brook, NY 11794-8101, USA. - - 2010
In nocturnal rodents, millisecond light ("flash") stimuli can induce both a large circadian rhythm phase shift and an associated state change from highly active to quiescence followed by behavioral sleep. Suppression of locomotion ("negative masking") is an easily measured correlate of the state change. The present mouse studies used both ...
Tang Chih-Hang Anthony CH Howard Hughes Medical Institute, National Center for Behavioral Genomics and Department of Biology, Brandeis University, Waltham, MA 02454, - - 2010
Circadian systems are entrained and phase shifted by light. In Drosophila, the model of light-mediated phase shifting begins with photon capture by CRYPTOCHROME (CRY) followed by rapid TIMELESS (TIM) degradation. In this study, we focused on phase delays and assayed TIM degradation within individual brain clock neurons in response to ...
Bass Caroline E CE Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Winston-Salem, North Carolina 27101, USA. - - 2010
Using a discrete trials (DT) procedure, we have previously shown that rats exhibit variations in their pattern of cocaine self-administration relative to the time-of-day, often producing a daily rhythm of intake in which the majority of infusions occur during the dark phase of the 24 h light-dark cycle. We have ...
González-Menéndez Irene - - 2010
To study the melanopsin system of the albino CD1 mouse retina during postnatal development. Pups were kept under different ambient conditions: light/dark (LD) cycles, constant light (LL), constant darkness (DD), LL followed by LD, and DD followed by LL. Using immunohistochemistry, melanopsin-expressing cells were classified as M1 or M2 according ...
1 2 3 4 5 6 7 8 9 10 >