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1.
Opt Express ; 21(13): 15144-54, 2013 Jul 01.
Article in English | MEDLINE | ID: mdl-23842301

ABSTRACT

We present a coupler design allowing normally-incident light coupling from free-space into a monomode photonic crystal waveguide operating in the slow-light regime. Numerical three-dimensional calculations show that extraction efficiencies as high as 80% can be achieved for very large group indices up to 100. We demonstrate experimentally the device feasibility by coupling and extracting light from a photonic crystal waveguide over a large group-index range (from 10 to 60). The measurements are in good agreement with theoretical predictions. We also study numerically the impact of various geometrical parameters on the coupler performances.

2.
Opt Express ; 20(24): 27403-10, 2012 Nov 19.
Article in English | MEDLINE | ID: mdl-23187597

ABSTRACT

We start from a 2D photonic crystal nanocavity with moderate Q-factor and dynamically increase it by two order of magnitude by the joint action of coherent population oscillations and nonlinear refractive index.


Subject(s)
Computer Simulation , Light , Nanotechnology/instrumentation , Optical Devices , Photons , Refractometry/instrumentation , Scattering, Radiation , Computer-Aided Design , Crystallization , Equipment Design , Nonlinear Dynamics
3.
Phys Rev Lett ; 109(11): 113903, 2012 Sep 14.
Article in English | MEDLINE | ID: mdl-23005630

ABSTRACT

Slow light induced by coherent population oscillations and cavity dispersive nonlinear response are combined achieving 2 orders of magnitude enhancement of the group delay and an equivalent decreasing of the spectral linewidth of a L3 two-dimensional photonic crystal nanocavity.

4.
Environ Entomol ; 37(3): 636-49, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18559169

ABSTRACT

Female gypsy moths, Lymantria dispar L., from 46 geographic strains were evaluated for flight capability and related traits. Males from 31 of the same strains were evaluated for genetic diversity using two polymorphic cytochrome oxidase I mitochondrial DNA restriction sites, the nuclear FS1 marker, and four microsatellite loci. Females capable of strong directed flight were found in strains that originated from Asia, Siberia, and the northeastern parts of Europe, but flight capability was not fixed in most strains. No flight-capable females were found in strains from the United States or southern and western Europe. Wing size and musculature were shown to correlate with flight capability and potentially could be used in predicting female flight capability. The mtDNA haplotypes broadly separated the gypsy moth strains into three groups: North American, European/Siberian, and Asian. Specific microsatellite or FS1 alleles were only fixed in a few strains, and there was a gradual increase in the frequency of alleles dominant in Asia at both the nuclear and microsatellite loci moving geographically from west to east. When all the genetic marker information was used, 94% of the individuals were accurately assigned to their broad geographic group of origin (North American, European, Siberian, and Asian), but female flight capability could not be predicted accurately. This suggests that gene flow or barriers to it are important in determining the current distribution of flight-capable females and shows the need for added markers when trying to predict female flight capability in introduced populations, especially when a European origin is suspected.


Subject(s)
DNA, Mitochondrial/genetics , Flight, Animal , Genetic Variation , Moths/physiology , Animals , Female , Genotype , Geography , Haplotypes , Male , Microsatellite Repeats , Moths/anatomy & histology , Moths/genetics , Muscle Strength , Polymorphism, Restriction Fragment Length , Wings, Animal/anatomy & histology
5.
Environ Entomol ; 36(2): 484-94, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17445385

ABSTRACT

A clinal female flight polymorphism exists in the gypsy moth, Lymantria dispar L., where female flight diminishes from east to west across Eurasia. A Russian population where females are capable of sustained ascending flight and a North American population with females incapable of flight were crossed: parentals, reciprocal F(1) hybrids, double reciprocal F(2) hybrids, and all possible backcrosses to both the parental lines were compared. Heritabilities were estimated using a threshold model, female offspring on female parent regressions, and joint-scaling analyses. Heritability of female flight capability measured using a free flight test was at least 0.60, and variation in wing size, muscle strength, and flight behaviors contributed to the flight polymorphism. Relative wing size varied continuously and had a heritability of 0.70. Environmental variation accounted for >90% of the variation in female preflight weight and relative flight muscle strength, as estimated by an inverted female's ability to right herself. Preflight walking behavior and early deposition of eggs were each inherited through a single gene with two co-dominant alleles. There was no evidence for sex-linkage or maternal effects in female flight capability or associated traits. Continued vigilance to exclude and eradicate introductions of strains capable of female flight in North America is warranted even in areas where no females fly, because some of the alleles needed for full flight capability may not be present in the North American populations, and some flight capability is maintained in the hybrids that could increase the rate of spread of L. dispar.


Subject(s)
Flight, Animal/physiology , Moths/genetics , Moths/physiology , Selection, Genetic , Alleles , Animals , Asia , Crosses, Genetic , Europe , Female , Male , Muscle Strength/genetics , North America , Polymorphism, Genetic , Species Specificity , Wings, Animal/anatomy & histology
6.
Biull Eksp Biol Med ; 109(6): 575-6, 1990 Jun.
Article in Russian | MEDLINE | ID: mdl-2168774

ABSTRACT

Levels of triiodothyronine, thyroxine, insulin, glucose and free fatty acids in the blood; contents of adrenaline, noradrenaline in adrenals and glycogen in the liver; activity of phenylethanolamine-N-methyltransferase in adrenals, hexokinase and glucose-6-phosphatase in the liver were studied in male Wistar rats and rats with inherited stress-induced arterial hypertension /ISIAH/. It was found that genetically caused rise of hypophyseal-thyroid systems activity in ISIAH-rats leads to a decrease of insulin blood level, activation of lipolysis and breach of glucose tolerance.


Subject(s)
Hypertension/physiopathology , Adrenal Glands/analysis , Adrenal Glands/enzymology , Animals , Blood Glucose/analysis , Epinephrine/analysis , Fatty Acids, Nonesterified/blood , Glucose-6-Phosphatase/analysis , Hexokinase/analysis , Hypertension/blood , Hypertension/metabolism , Insulin/blood , Liver/enzymology , Liver Glycogen/analysis , Male , Norepinephrine/analysis , Phenylethanolamine N-Methyltransferase/analysis , Rats , Rats, Inbred SHR , Rats, Inbred Strains , Thyroxine/blood , Triiodothyronine/blood
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