Genetic heterogeneity and ploidy level analysis among different gynogenetic clones of the polyploid gibel carp

Background: Some triploid and tetraploid clones have been identified in the gynogenetic gibel carp, Carassius auratus gibelio Bloch, by karyotypic and cytologic analyses over many years. Further, 5-20% males and karyotypic diversity have been found among their natural and artificial populations. However, the DNA contents and the relation to their ploidy level and chromosome numbers have not been ascertained, and whether normal meiosis occurs in spermatogenesis needs to be determined in the different clones. Methods: The sampled blood cells or sperms were mixed with blood cells from chicken or individual gibel carp and fixed in 70% pre-cooled ethanol overnight at 4degreesC. The mixed cell pellets were washed 2-3 times in 1x phosphate buffered saline and then resuspended in the solution containing 0.5% pepsin and 0.1 M HCl. DNA was stained with propidium iodide solution (40 mug/mL) containing 4 kU/ml RNase. The measurements of DNA contents were performed with Phoenix Flow Systems. Results: Triploid clones A, E, F, and P had almost equal DNA content, but triploid clone D had greater DNA content than did the other four triploid clones. DNA content of clone M (7.01 +/- 0.15 pg/nucleus) was almost equal to the DNA content of clone D (5-38 +/- 0.06 pg/nucleus) plus the DNA content of common carp sperm (1.64 +/- 0.02 pg/nucleus). The DNA contents of sperms from clones A, P, and D were half of their blood cells, suggesting that normal meiosis occurs in spermatogenesis. Conclusions: Flow cytometry is a powerful method to analyze genetic heterogeneity and ploidy level among different gynogenetic clones of polyploid gibel carp. Through this study, four questions have been answered. (a) The DNA content correlation among the five triploid clones and one multiple tetraploid clone was revealed in the gibel carp, and the contents increased with not only the ploidy level but also the chromosome number. (b) Mean DNA content was 0.052 pg in six extra chromosomes of clone D, which was higher than that of each chromosome in clones A, E, F, and P (about 0.032 pg/ chromosome). This means that the six extra chromosomes are larger chromosomes. (c) Normal meiosis occurred during spermatogenesis of the gibel carp, because DNA contents of the sperms from clones A, P, and D were almost half of that in their blood cells. (d) Multiple tetraploid clone M (7.01 +/- 0.15 pg/nucleus) contained the complete genome of clone D (5.38 +/- 0.06 pg/nucleus) and the genome of common carp sperm (1.64 +/- 0.02 pg/nucleus). Cytometry Part A 56A:46-52, 2003. (C) 2003 Wiley-Liss, Inc.

Karyotypic diversity in polyploid gibel carp, Carassius auratus gibelio Bloch

Polyploid gibel carp, Carassius auratus gibelio, is an excellent model system for evolutionary genetics owing to its specific genetic background and reproductive modes. Comparative karyotype studies were performed in three cultured clones, one artificially manipulated group, and one mated group between two clones. Both the clones A and P had 156 chromosomes in their karyotypes, with 36 metacentric, 54 submetacentric, 36 subtelocentric, 24 acrocentric, and six small chromosomes. The karyotype of clone D contained 162 chromosomes, with 42 metacentric, 54 submetacentric, 36 subtelocentric, 24 acrocentric, and six small chromosomes. All the three clones had six small chromosomes in common. Group G, being originated from the clone D by artificial manipulation, showed supernumerary microchromosomes or chromosomal fragments, in addition to the normal chromosome complement that was identical to the clone D. The offspring from mating between clones D and A had 159 chromosomes. Comparing with the clone A, the DA offspring showed three extra metacentric chromosomes. In addition, variable RAPD fingerprint patterns and unusual SCAR marker inheritance were, respectively, detected among individuals of artificial group G and in the mated DA offspring. Both the chromosome and molecular findings suggest that genome reshuffling might have occurred by manipulation or mating of the clones.

Application of sampled grating to control the lasing wavelength in complex-coupled DFB laser

This paper reports that the complex-coupled distributed feedback laser with the sampled grating has been designed and fabricated. The +1st order reflection of the sampled grating is utilized for laser single mode operation, which is 1.5387 mu m in the experiment. The typical threshold current of the device is 30 mA, and the optical output power is about 10 mW at the injection current of 100 mA.

Integratable and High Speed Complex-Coupled MQW-DFB Lasers Fabricated on Semi-Insulating Substrates

A novel integratable and high speed InGaAsP multi-quantum well (MQW) complex-coupled distributed feedback (DFB) laser is successfully fabricated on a semi-insulating substrate. The fabricated ridge DFB laser exhibits a threshold current of 26 mA, a slope efficiency of 0.14 W.A(-1) and a side mode suppression ratio of 40 dB together with a 3 dB bandwidth of more than 8 GHz. The device is suitable for 10 Gbit/s optical fiber communication.

Control of the lasing wavelength by a sampled grating in a complex-coupled DFB laser

The lasing wavelength of a complex-coupled DFB laser is controlled by a sampled grating. The key concepts of the approach are to utilize the -1st order (negative first order) reflection of a sampled grating for laser single mode operation, and use conventional holographic exposure combined with the usual photolithography to fabricate the sampled grating. The typical threshold current of the sampled grating based DFB laser is 32 mA, and the optical output is about 10 mW at an injected current of 100 mA. The lasing wavelength of the device is 1.5356 mu m, which is the -1st order wavelength of the sampled grating.

Comparison of the properties of GaN grown on complex Si-based structures

With the aim of investigating the possible integration of optoelectronic devices, epitaxial GaN layers have been grown on Si(Ill) semiconductor-on-insulator (SOI) and on Si/CoSi2/Si(111) using metalorganic chemical vapor deposition. The samples are found to possess a highly oriented wurtzite structure, a uniform thickness, and abrupt interfaces. The epitaxial orientation is determined as GaN(0001)//Si(111), GaN[1120]//Si[110], and GaN[1010]//Si[112], and the GaN layer is tensilely strained in the direction parallel to the interface. According to Rutherford backscattering/channeling spectrometry and (0002) rocking curves, the crystalline quality of GaN on Si(111) SOI is better than that of GaN on silicide. Room-temperature photoluminescence of GaN/SOI reveals a strong near-band-edge emission at 368 nm (3.37 eV) with a full width at half-maximum of 59 meV. (c) 2005 American Institute of Physics.

Complex quantum ring structures formed by droplet epitaxy

Well-defined complex quantum ring structures formed by droplet epitaxy are demonstrated. By varying the temperature of the crystallizing Ga droplets and changing the As flux, GaAs/AlGaAs quantum single rings and concentric quantum double rings are fabricated, and double-ring complexes are observed. The growth mechanism of these quantum ring complexes is addressed. (c) 2006 American Institute of Physics.

A complex Fourier transformation study of the contactless electroreflectance of an undoped-n(+) GaAs structure

Complex Fourier transformation (CFT) has been employed to analyse contactless electroreflectance (CER) spectra from an undoped-n(+) GaAs structure with various ac modulations and dc bias voltages. The CFT spectra of CER have been compared with those of photoreflectance (PR). It has been found that the CER non-flat modulation is between the built-in electric field and a larger electric field which increases with the modulation voltage. The result has been explained by the screening of the applied modulation electric field in one of the two half modulation cycles and the trapping of electrons in surface states in the other half modulation cycle. The dc bias does not change the CER spectra, hence their CFT spectra. This is because of the screening of the applied dc bias electric field.

Epitaxial growth of SiC on complex substrates

Epitaxial growth of SiC on complex substrates was carried out at substrate temperature from 1200 degreesC to 1400 degreesC. Three kinds of new complex substrates, c-plane sapphire, AlN/sapphire, and GaN/AlN/sapphire, were used in this study. We obtained a growth rate in the range of 1-6 mum/h. Thick (6 mum) SIC epitaxial layers with no cracks were successfully obtained on AlN/sapphire and GaN/AlN/sapphire substrates. X-ray diffraction patterns have confirmed that single-crystal SiC was obtained on these complex substrates. Analysis of optical transmission spectra of the SIC grown on sapphire substrates shows the lowest-energy gap near 2.2 eV, which is the value for cubic SiC. The undoped SIC showed n-type electrical conductivity. (C) 2001 Elsevier Science B.V. All rights reserved.

Application of the compatibility relationship(1) in seeking a functional relationship among species' equilibrium quantities in complex systems

A new algorithm, representing an important advance in determination of the functional relationship, is first reported here. The algorithm is very useful and convenient for analyzing the incorporation of impurities. To show how the algorithm works, two early and well-known vapor phase epitaxy (VPE) experiments-Ashen's (Ashen, D. J.; Dean, P. J.; Hurle, D. T. J.; Mullin, J. B.; Royle, A.; White, A. M. Gallium Arsenide and Related Compounds, Institute of Physics Conference Series 24, 1974; Institute of Physics: London, 1975; p 229.), involving the doping of silicon and DiLorenzo's (DiLorenzo, J. V. J. Cryst. Growth 1972, 17, 189.), involving the mole fraction effect-are calculated to find the functional relationship between the Si contamination and the partial pressure of HCl. The calculated curves agree with the experimental results. A conclusion that the calculated values are greater than the true values has been drawn.

Compensation ratio-dependent concentration of a VInH4 complex in n-type liquid encapsulated Czochralski InP

The concentration of hydroen-indium vacancy complex VInH4 in liquid encapsulated Czochralski undoped and Fe-doped n-type InP has been studied by low-temperature infrared absorption spectroscopy. The VInH4 complex is found to be a dominant intrinsic shallow donor defect with concentrations up to similar to 10(16) cm(-3) in as-grown liquid encapsulated Czochralski InP. The concentration of the VInH4 complex is found to increase with the compensation ratio in good agreement with the proposed defect formation model of Walukiewicz [W. Walukiewicz, Phys. Rev. B 37, 4760 (1998); Appl. Phys. Lett. 54, 2094 (1989)], which predicts a Fermi-level-dependent concentration of amphoteric defects. (C) 1998 American Institute of Physics, [S0003-6951(98)04435-0].

A novel 1.3-mu m high T-0 AlGaInAs/InP strained-compensated multi-quantum well complex-coupled distributed feedback laser diode

A 1.3-mu m AlGaInAs/InP buried heterostructure (BH) stripe distributed feedback laser with a novel AlInAs/InP complex-coupled grating grown by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) is proposed and demonstrated. A high characteristic temperature (T-0 = 90K between 20-80 degrees C) and temperature-insensitive slope efficiency (0.25 dB drop from 20 to 80 degrees C) in 1.3 mu m AlGaInAs/InP DFB lasers was obtained by introducing AI(Ga)InAs graded-index separate-confinement heterostructure (GRINSCH) layers and a strained-compensated (SC) multi-quantum well (MQW).

A Complex BPF with On Chip Auto-tuning Architecture for Wireless Receivers

A 3(rd) order complex band-pass filter (BPF) with auto-tuning architecture is proposed in this paper. It is implemented in 0.18um standard CMOS technology. The complex filter is centered at 4.092MHz with bandwidth of 2.4MHz. The in-band 3(rd) order harmonic input intercept point (IIP3) is larger than 16.2dBm, with 50 Omega as the source impedance. The input referred noise is about 80uV(rms). The RC tuning is based on Binary Search Algorithm (BSA) with tuning accuracy of 3%. The chip area of the tuning system is 0.28 x 0.22 mm(2), less than 1/8 of that of the main-filter which is 0.92 x 0.59 mm(2). After tuning is completed, the tuning system will be turned off automatically to save power and to avoid interference. The complex filter consumes 2.6mA with a 1.8V power supply.

A Complex BPF with On Chip Auto-tuning Architecture for Low-IF Receivers

A 3(rd) order complex band-pass filter (BPF) with auto-tuning architecture is proposed in this paper. It is implemented in 0.18 mu m standard CMOS technology. The complex filter is centered at 4.092MHz with bandwidth of 2.4MHz. The in-band 3(rd) order harmonic input intercept point (IIP3) is larger than 19dBm, with 50 Omega as the source impedance. The input referred noise is about 80 mu V-rms. The RC tuning is based on Binary Search Algorithm (BSA) with tuning accuracy of 3%. The chip area of the tuning system is 0.28x0.22mm(2), less than 1/8 of that of the main-filter which is 0.92x0.59mm(2). After tuning is completed, the tuning system will be turned off automatically to save power and to avoid interference. The complex filter consumes 2.6mA with a 1.8V power supply.

Research of Face Detection System Applied for Detecting Faces with Complex Background and Illumination

An effective face detection system used for detecting multi pose frontal face in gray images is presented. Image preprocessing approaches are applied to reduce the influence of the complex illumination. Eye-analog pairing and improved multiple related template matching are used to glancing and accurate face detecting, respectively. To shorten the time cost of detecting process, we employ prejudge rules in checking candidate image segments before template matching. Test by our own face database with complicated illumination and background, the system has high calculation speed and illumination independency, and obtains good experimental results.