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Growth performance and physiological parameters of the second generation selected and control groups of Pinctada martensii 被引量:10
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作者 DENG Yuewen YU Ziniu +2 位作者 DU Xiaodong WANG Qingheng FU Shao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期120-125,共6页
In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the... In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the first generation selected group.Growth performance of the SS and SC groups were compared on the basis of measurement data at Days 8,18,60,95,195 and 365.On Day 365,100 individuals (60.0–75.0 mm at shell length) were sampled from each group and then subjected to the experiment where physiological parameters such as filtrate rate,oxygen consumption and ammonia excretion were measured at 15,20,25 and 30°C.The results show that the SS group had significantly larger mean shell length and shell height than the SC group at Days 8,18,60,95,195 and 365 (P 0.05).The genetic gains at different ages varied from 6.0% to 17.0% for shell length and 5.7% to 14.6% for shell height,respectively.At 15,20,25 and 30 ° C,the SS groups had significantly larger filtrate rate than the SC group (P 0.05).At 15 and 25 °C,the differences in oxygen consumption rate between the SS and SC groups were not significant (P 0.05).At 20 and 30 °C,however,the oxygen consumption rate of the SS group was significantly larger than the SC group (P 0.05).At 15,20,25 and 30 °C,there were no significant differences in ammonia excretion rate between the SS and SC groups (P 0.05).The present results indicate that there existed considerable genetic variability in the base population and a further selection could be likely fruitful.Mass selection for faster growth might produce animals that had higher intake of metabolizable energy by virtue of faster filtrating behavior. 展开更多
关键词 Pinctada martensii the second generation selected group GROWTH genetic gains physiological parameters
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The Lifting Scheme Based on the Second Generation Wavelets 被引量:1
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作者 FENG Hui GUO Lanying XIAO Jinsheng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期503-506,共4页
The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing t... The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing time with its particular frame. This paper aims at introducing the second generation wavelets, begins with traditional Mallat algorithms, illustrates the lifting scheme and brings out the detail steps in the construction of Biorthogonal wavelets. Because of isolating the degrees of freedom remaining the biorthogonality relations, we can fully control over the lifting operators to design the wavelet for a particular application, such as increasing the number of the vanishing moments. 展开更多
关键词 lifting scheme the second generation wavelets vanishing moments
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QM/MM Study of the Second Harmonic Generation and Two-photon Absorption Properties of a Fluorescent Proteins-Dreiklang
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作者 张敏熠 魏婧 +2 位作者 宋金帅 吴鹏 李春森 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第9期1393-1403,共11页
A new reversibly switchable fluorescent protein(RSFP), namely Dreiklang, exhibits prominent feature that the wavelengths for switching and fluorescence are decoupled due to its great different structures between bri... A new reversibly switchable fluorescent protein(RSFP), namely Dreiklang, exhibits prominent feature that the wavelengths for switching and fluorescence are decoupled due to its great different structures between bright and dark states. This feature might also induce some nonlinear optic(NLO) properties changing as switching between two states, which might promote new method of biological science. We employ the QM/MM method to simulate the structures of different states, and study their second harmonic generation(SHG) and two-photon absorption(TPA) properties. And we found different states of Dreiklang have different SHG and TPA responses. The SHG and TPA properties of Dreiklang are correlated to particularly geometrical structures of different states, especially the centrosymmetric or nocentrosymmetric π-stacking structures which are formed by chromophore and beside residue Tyr203, so the SHG and TPA responses could be changed as the light induces switching among different states of Dreiklang. This work would prospectively guide the application of Dreiklang on the NLO technology, and help the development of new RSFP with special NLO function. 展开更多
关键词 fluorescent proteins the second harmonic generation two-photon absorption QM/MM method
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Becoming Adults During an Economic Crisis: What Happens to the Second Generations?
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作者 Roberta Ricuccia 《Sociology Study》 2013年第10期752-762,共11页
The paper presents findings of an empirical study carried out in an Italian area and focused on the effects of the economic crisis on immigrant families: the goal was to identify how the difficulties of these years ... The paper presents findings of an empirical study carried out in an Italian area and focused on the effects of the economic crisis on immigrant families: the goal was to identify how the difficulties of these years (not only socio-economic but also in terms of negative attitudes toward immigrants) affect on the life-paths of second generations. What happens to their school career? Are they forced to leave school in order to improve the family's income? Are they sent back to the country of origin of their parents to reduce life-costs in the immigration country? Thanks to a collection of around 30 interviews with young people between 18-24 years old and 30 interviews with both parents and social workers, the strategies which families are choosing to face economic and labour difficulties and their effects on integration paths and inter-ethnic relations will be described. 展开更多
关键词 Economic crisis the second generations INTEGRATION MIGRATION
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A New OFDM System Based on Lifting Wavelet Transform for Wireless Channel 被引量:2
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作者 GAO Jian-bo ZHAO Er-yuan 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2005年第3期21-25,共5页
It is well known that the Orthogonal Frequency Division Multiplexing ( OFDM ) system has a high ability to overcome the effect of multipath and can obtain high spectral efficiency in the wireless communication chann... It is well known that the Orthogonal Frequency Division Multiplexing ( OFDM ) system has a high ability to overcome the effect of multipath and can obtain high spectral efficiency in the wireless communication channel. However, avoid Interchannel Interference (ICI) and Intersymbol Interference (ISI) in wireless channel, a guard interval longer than channel delay is used in conventional OFDM system, which cause the efficiency of bandwidth usage reduced. Due to the superior spectral containment of wavelets, this paper proposed a new OFDM system based on Lifting Wavelet Transform (LWT-OFDM), which adopts lifting wavelet transform to replace the conventional Fourier transform. This new OFDM system doesn't need the Cyclic Prefix (CP) so its structure is more simply than FFT-OFDM and its algorithm is as simply as FFT-OFDM. The new LWT-OFDM system can mitigates some disadvantages of FFT-OFDM system, such as a relatively large peak-to-average power ratio, more sensitive to carrier frequency offset and phase noise. Simulations show that the LWT-OFDM system is more effective and attractive than conversional FFT-OFDM in wireless channel. 展开更多
关键词 OFDM 4G wavelet transform lifting theory. the second generation wavelet signal processing
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