Embryonic stages and eye-specific gene expression of the local cyprinoid fish Anabarilius grahami in Fuxian Lake, China

Anabarilius grahami is a cyprinoid fish endemic to Fuxian Lake, Yunnan, China. In this study, a comprehensive staging series of A. grahami was produced. The embryonic development of A. grahami was divided into six main periods: zygote period, cleavage per

Age-related effects of bilateral frontal eye fields lesions on rapid eye movements during REM sleep in rhesus monkeys

Rapid eye movement (REM) is one of the most characteristic features of REM sleep, but the mechanisms underlying its regulation remain unclear. The present study aims to investigate whether the frontal eye field (FEF) is involved in the regulation of the r

Ectopic Six3 expression in the dragon eye goldfish

For goldfish (Carassius auratus), there are many varieties with different eye phenotypes due to artificial selection and adaptive evolution. Dragon eye is a variant eye characterized by a large-size eyeball protruding out of the socket similar to the eye of dragon in Chinese legends. In this study, anatomical structure of the goldfish dragon eye was compared with that of the common eye, and a stretching of the retina was observed in the enlarged dragon eye. Moreover, the homeobox-containing transcription factor Six3 cDNAs were cloned from the two types of goldfish, and the expression patterns were analyzed in both normal eye and dragon eye goldfish. No amino acid sequence differences were observed between the two deduced peptides, and the expression pattern of Six3 protein in dragon eye is quite similar to common eye during embryogenesis, but from 2 days after hatching, ectopic Six3 expression began to occur in the dragon eye, especially in the outer nuclear layer cells. With eye development, more predominant Six3 distribution was detected in the outer nuclear layer cells of dragon eye than that of normal eye, and fewer cell-layers in outer nuclear layer were observed in dragon eye retina than in normal eye retina. The highlight of this study is that higher Six3 expression occurs in dragon eye goldfish than in normal eye goldfish during retinal development of larvae. (C) 2007 Elsevier Inc. All rights reserved.

Bioaccumulation of the hepatotoxic microcystins in various organs of a freshwater snail from a subtropical Chinese lake, Taihu lake, with dense toxic microcystis blooms

In this paper, we describe the seasonal dynamics of three common microcystins (MCs MC-RR, MC-YR, and MC-LR) in the whole body, hepatopancreas, intestine, gonad, foot, remaining tissue, and offspring of a freshwater snail, Bellamya aeruginosa, from Gonghu Bay of Lake Taihu, China, where dense toxic Microcystis blooms occur in the warm seasons. Microcystins were determined by liquid chromatography electrospray ionization mass spectrum. Microcystin (MC-RR + MC-YR + MC-LR) content of the offspring and gonad showed high positive correlation, indicating that microcystins could transfer from adult females to their young with physiological connection. This study is the first to report the presence of microcystins in the offspring of the adult snail. The majority of the toxins were present in the intestine (53.6%) and hepatopancreas (29.9%), whereas other tissues contained only 16.5%. If intestines are excluded, up to 64.3% of the toxin burden was allocated in the hepatopancreas. The microcystin content in the intestine, hepatopancreas, and gonad were correlated with the biomass of Microcystis and intracellular and extracellular toxins. Of the analyzed foot samples, 18.2% were above the tolerable daily microcystin intake recommended by the World Health Organization (WHO) for human consumption. This result indicates that public health warnings regarding human ingestion of snails from Taihu Lake are warranted. In addition, further studies are needed to evaluate the occurrence by Microcystis in relation to spatial and temporal changes in water quality.

Tandem organic light-emitting diodes with an effective charge-generation connection structure

The tandem organic light-emitting diodes (OLEDs) with an effective charge-generation connection structure of Mg-doped tris(8-hydroxyquinoline) aluminum (Alq(3))/Molybdenum oxide (MoO3)-doped 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) were presented. At a current density of 50 mA/cm(2), the current efficiency of the tandem OLED with two standard NPB/Alq(3) emitting units is 4.2 cd/A, which is 1.7 times greater than that of the single EL device. The tandem OLED with the similar connection structure of Mg-doped PTCDA/MoO3-doped PTCDA was also fabricated and the influences of the different connection units on the current efficiency of the tandem OLED were discussed as well.

Eye-safe, high-energy, single-mode all-fiber laser with widely tunable repetition rate

We present a novel high-energy, single-mode, all-fiber-based master-oscillator-power-amplifier (MOPA) laser system operating in the C-band with 3.3-ns pulses and a very widely tunable repetition rate, ranging from 30 kHz to 50 MHz. The laser with a maximum pulse energy of 25 mu J and a repetition rate of 30 kHz is obtained at, a wavelength of 1548 nm by using a double-clad, single-mode, Er:Yb co-doped fiber power amplifier.

Visual-Context Boosting for Eye Detection

Eye detection plays an important role in many practical applications. This paper presents a novel two-step scheme for eye detection. The first step models an eye by a newly defined visual-context pattern (VCP), and the second step applies semisupervised boosting for precise detection. VCP describes both the space and appearance relations between an eye region (region of eye) and a reference region (region of reference). The context feature of a VCP is extracted by using the integral image. Aiming to reduce the human labeling efforts, we apply semisupervised boosting, which integrates the context feature and the Haar-like features for precise eye detection. Experimental results on several standard face data sets demonstrate that the proposed approach is effective, robust, and efficient. We finally show that this approach is ready for practical applications.

G-quadruplex-based DNAzyme for sensitive mercury detection with the naked eye

Hg2+ is able to inhibit the peroxidase-like DNAzyme function of a T-containing G-quadruplex DNA via Hg2+-mediated T-T base pairs, which enables the visual detection of Hg2+ in the TMB-H2O2 reaction system with high selectivity and sensitivity.

Efficient tandem polymer photovoltaic cells with two subcells in parallel connection

Tandem polymer photovoltaic cells with the subcells having different absorption characteristics in series connection are widely investigated to enhance absorption coverage over the solar spectrum. Herein. we demonstrate efficient tandem polymer photovoltaic cells with the two stacked subcells comprising different band-gap conjugated polymer and fullerene derivative bulk heterojunction in parallel connection. A semitransparent metal layer combined with inorganic semiconductor compounds is utilized as the intermediate electrode of the two stacked subcells to create the required built-in potential for collecting photo-generated charges. The short-circuit current of the stacked cell is the sum of the subcells and the open-circuit voltage is similar to the subcells.