One of the most fascinating predictions of the theory of general relativity is the effect of gravitational lensing, the bending of light in close proximity to massive stellar objects. Recently, artificial optical materials have been proposed to study the various aspects of curved spacetimes, including light trapping and Hawking's radiation. However, the development of experimental toy models that simulate gravitational lensing in curved spacetimes remains a challenge, especially for visible light. Here, by utilizing a microstructured optical waveguide around a microsphere, we propose to mimic curved spacetimes caused by gravity, with high precision. We experimentally demonstrate both far-field gravitational lensing effects and the critical phenomenon in close proximity to the photon sphere of astrophysical objects under hydrostatic equilibrium. The proposed microstructured waveguide can be used as an omnidirectional absorber, with potential light harvesting and microcavity applications.Comment: 17 pages, 4 figures. This work is published at Nature Photonics, Published online: 29 September 201

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An 8‐week experiment on fingerling black carp Mylopharyngodon piceus was conducted to evaluate the effects of dietary fish oil (FO) supplement on growth, fatty acid composition and non‐specific immunity responses. Five triplicate fingerling groups (initial weight = 2.72 ± 0.35 g) were fed isoenergetic and isonitrogenous diets in which the dietary FO was replaced with rapeseed oil (RO) in graded increments of 25% (0–100%). No significant effects were observed on specific growth rates, survival rates and feed conversion ratios, but there were significant differences in whole body moisture and liver lipid contents (P < 0.05), and the 100% RO replacement diet significantly enhanced hepatosomatic indexes compared to control group (P < 0.05). Other approximate whole body constituents, viscerasomatic ratios and condition factors were not influenced by dietary oil treatments. Fatty acid composition of muscle and liver was influenced by dietary fatty acid input, α‐linoleic acid and γ‐linolenic acid were significantly increased with increasing RO, but eicosapentaenoic acid, docosahexaenoic acid and the n‐3/n‐6 ratio were significantly reduced (P < 0.05). Alternative complement pathway, lysozyme and superoxide dismutase activities were not significantly influenced. These results indicate that black carp fed diets with FO supplement had similar growth and non‐specific immunity to the fish fed diet with RO.

The four main Chinese carps, collectively abbreviated as MCHA, include the black carp (Mylopharyngodon piceus), grass carp (Ctenop haryngodon idellus), silver carp (Hypoph thal michthys molitrix), and the big‐head carp (Aristichyths nobilis). MCHA constitutes a significant catch of China's fresh water fishery. The construction of the Gezhouba and Three Gorges Dams greatly affects the physical habitat conditions of these four main carp species. This paper presents a time‐series model for the assessment of instantaneous physical conditions in MCHA habitats. The model incorporates the effects of various hydrological variables (e.g. water level fluctuation, water temperature and sediment concentration) on MCHA habitat quality. The model is tested for the Yichang‐Zhijiang reaches of the Yangtze River – a suitable region for analysing the effects of dam construction on the physical conditions of MCHA habitat. The model analyses instream ecological flow (IEF) characteristics of the study area in the spawning season of MCHA. On the basis of the analysis, the min, max and optimal IEFs are 6200, 51000 and 14 500 m3/s, respectively. The model introduces an efficient method for calculating the instantaneous habitat area on the basis of IEF and other physical conditions. If properly applied, the model is an efficient tool for assessing the effects of variations in flow conditions on MCHA habitat quality. The model could also be used in real time to analyse the combined effect of ecological regulations (e.g. as induced by the Three Gorges and Gezhouba Dams) on MCHA spawning conditions. Copyright © 2012 John Wiley & Sons, Ltd.

Our study reveals a compound mutation consisting of a large deletion and a nonsense mutation, which provides a new insight in the mutation type of CTSC gene.