Dynamic expressions of hypothalamic genes regulate seasonal breeding in a natural rodent population

Seasonal breeding is a universal reproductive strategy in many animals. Hypothalamic genes, especially type 2 and 3 iodothyronine deiodinases (Dio2/3), RFamide-related peptide 3 (Rfrp-3), kisspeptin (Kiss-1), and gonadotropin-releasing hormone (GnRH), are involved in a photoperiodic pathway that encodes seasonal signals from day length in many vertebrate species. However, the seasonal expression patterns of these genes in wild mammals are less studied. Here, we present a four-year field investigation to reveal seasonal rhythm and age-dependent reproductive activity in male Brandt's voles (Lasiopodomys brandtii) and to detect relationships among seasonal expression profiles of hypothalamic genes, testicular activity, age, and annual day length. From breeding season (April) to non-breeding season (October), adult male voles displayed a synchronous peak in gonadal activity with annual day length around summer solstice, which was jointly caused by age structure shifts and age-dependent gonadal development patterns. Overwintered males maintained reproductive activity until late in the breeding season, whereas most newborn males terminated gonadal development completely, except for a minority of males born early in spring. Consistently, the synchronous and opposite expression profiles of Dio2/3 suggest their central function to decode photoperiodic signals and to predict the onset of the non-breeding season. Moreover, changes in Dio2/3 signals may guide the actions of Kiss-1 and Rfrp-3 to regulate the age-dependent divergence of reproductive strategy in wild Brandt's vole. Our results provide evidence on how hypothalamic photoperiod genes regulate seasonal breeding in a natural rodent population. This article is protected by copyright. All rights reserved

Swelling Behaviors of Superabsorbent Composites Based on Acrylic Acid/Acrylamide Copolymer and Attapulgite

The swelling behaviors and water retention of superabsorbent sand-fixing materials prepared from acrylic acid/acrylamide copolymer (AA/AM) and acid-modified attapulgite under ultrasonic treatments and different pH conditions were investigated. The results demonstrated that a suitable amount of attapulgite can effectively improve the absorption capacity and saltwater performance. The superabsorbent achieved the highest absorptions of 1257.54 g/g and 209.45 g/g in distilled water and a 0.9 wt% NaCl solution, and a higher water absorbency occurred over a wide pH range of 5~9 when the ultrasonic power was 200 W and the attapulgite content was 10%. The addition of attapulgite could significantly increase the water absorption and retention

Design and fabrication of high efficiency diffuser film based on laser speckle

Conference Name:6th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies. Conference Address: Xiamen, China. Time:April 26, 2012 - April 29, 2012.The Chinese Optical Society (COS); Inst. Opt. Electron. (IOE), Chinese Acad. Sci. (CAS)Diffuser film is one of the main components in liquid crystal display backlight unit. It can cause strong scattering for the light out from the light guide plate, and it have the ability to make diffuse reflection and uniform diffusion of the out light occur. How to improve the brightness, the uniformity of backlight unit, and make it more and more slimmer are not only what manufacturers pursuit to, but also an hotspot recently. In this paper, we make use of the statistical analysis law of laser speckle to achieve the fabrication of diffuser film. According to the requirements for the technical parameters of diffuser film, the structure characteristics of laser speckle and manufacturing methods are analyzed and discussed in detail. They consist of producing the original edition of the laser speckle figure (Photoresist board was used as recording medium to produce embossment laser speckle images, and this is one of the most important process in moulding technology), using electricity molding system to manufacture metal formwork (It is also called as electrotyping, which is transfer the embossment speckle image from the photoresist board to a metal plate), and moulding replication (In a certain temperature and pressure, template stripes were transferred to the film). The diffusion light uniformity and brightness can be controlled via adjusting intensity distribution and average diameter of the speckles. Then the preliminary experiment results are given under laboratory conditions (argon ion laser, 位=457.9nm), and meanwhile the effects of several common diffuser films are compared in this paper. 漏 2012 SPIE

Optical Tweezers Array System Based on 2D Photonic Crystals

Conference Name:International Conference on Physics Science and Technology (ICPST). Conference Address: Hong Kong, PEOPLES R CHINA. Time:DEC 12-13, 2011.A simple optical interference method for creating multiple optical tweezers from a single laser beam, using two dimentional photonic crystals (PhCs) as a diffractive beam splitter, was described. To obtained clear periodic traps, all diffracted beams sould be used and the intensity of each splitted beam should be same. So the period and the surface features of PhCs was adjusted in the present study As a demonstration of this technique, using 2D PhCs with 700 nanometer period, hexagonal lattice patterns with one micrometer period have been implemented. The image of periodic intensity gradient of light fabricated by this method is presented. (C) 2011 Published by Elsevier B.V. Selection and/or peer-review under responsibility of Garry Lee

Optical matching system for eliminating lateral position displacement of holographic images under varying laser wavelength

Conference Name:9th International Symposium on Display Holography, ISDH 2012. Conference Address: Cambridge, MA, United states. Time:June 25, 2012 - June 29, 2012.The diffraction angle of a hologram is proportional to the wavelength so that a lateral displacement of the holographic image will occur when there is a change in wavelength. Such displacement is more serious when the image is generated at far distance. A matching system including an HOE and a hologram is proposed to eliminate the image lateral displacement under varying wavelength. Theoretical analysis demonstrates that the two elements must have the conditions: (a) They must have the same fringe periods; (b) They must be placed in parallel; (c) The diffracted beam from HOE must be collimated. The two elements were fabricated in the experiment and applied into a holographic sight. A test was carried out on the sight through watching the image lateral movement at 50-meter distance. The experimental result shows that under varying wavelength there is no image lateral displacement observed, verifying the effectiveness of the matching system. ? Published under licence by IOP Publishing Ltd

Enhancement of LED light extraction via diffraction of hexagonal lattice fabricated in ITO layer with holographic lithography and wet etching

A novel method for enhancing light extraction efficiency of LEDs via diffraction of the lattice fabricated in ITO layers of LEDs is proposed. The lattice fabrication process includes holographic lithography and wet etching. 3-beam interference holographic approach was used to fabricate large-area hexagonal lattice mask which can cover 2-inch semiconductor wafer, and acid etching was used to transfer the lattice structure into p-contact ITO layer. 1.4 fold enhancement of light output at 20 mA injection current was obtained from GaN-based LEDs in the primary experiment. The lattice fabrication process is rapid and cost-effective thus enabling industrial mass production of high brightness LEDs. (C) 2008 Elsevier B.V. All rights reserved

Reduction of sunlight reflection on surfaces of solar cells by fabricating hexagonal lattices in multicrystalline silicon

Conference Name:Conference on Solid State Lighting and Solar Energy Technologies. Conference Address: Beijing, PEOPLES R CHINA. Time:NOV 12-14, 2007.A new method for reducing surface reflectance of multicrystalline silicon wafers is presented. The method using holographic lithography and wet etching to fabricate 2-dimensional (213) photonic crystal (PC) on the surface of multicrystalline silicon. 2D hexangonal PC structures with micron scale lattice constant exhibit significant reduction of the surface reflectance. In the method, 2D hexagonal PC structure is firstly recorded in photoresist, which is coated on the surface of Si wafer, using holographic 3-beam interference technique. After exposure and development the wafer is put into acid solution to transfer the lattice structure into the silicon. Experiments with different exposure angles and etching times were carried out to form different lattice period and structure depth for obtaining optimal lattice parameters. PC with 1.3 mu m lattice constant and 0.5 mu m depth has achieved a reflectance below 6%. The holographic technique used in the work allows large-area lattice fabrication with only one process. The proposed method has the advantages of low production cost and high throughput, enabling industrial mass production of Si solar cells