Exchanging gifts at the holidays is a tradition that dates back to thousands of years ago.Children are typically excused from buying gifts because they cost money kids may not have.But the truth is that some of the be...Exchanging gifts at the holidays is a tradition that dates back to thousands of years ago.Children are typically excused from buying gifts because they cost money kids may not have.But the truth is that some of the best gifts don't cost anything.If you would like to give meaningful gifts to family or friends at the holidays—without having to spend money—here's how you can get started.展开更多
Even when kids dont realize it,teachers listen with their ears and their hearts.So many teachers dedi-cate their lives to education and helping us raise good kids.Some of them go so far above and beyond the call of du...Even when kids dont realize it,teachers listen with their ears and their hearts.So many teachers dedi-cate their lives to education and helping us raise good kids.Some of them go so far above and beyond the call of duty that it makes you wonder if they are really angels in disguise.Stacy Caldwell is one of those teachers.展开更多
The 51st China Beijing International Gifts,Premium and Houseware Exhibition(hereinafter referred to as the Gifts Exhibition) officially opened the kaleidoscope of creative gifts at China International Exhibition Cente...The 51st China Beijing International Gifts,Premium and Houseware Exhibition(hereinafter referred to as the Gifts Exhibition) officially opened the kaleidoscope of creative gifts at China International Exhibition Center (Chaoyang Pavilion) on March 20th.More than 900 exhibitors built an aesthetic corridor of quality life with 200,000 gifts.展开更多
From August 14 to 16,the 52nd China Beijing International Gifts,Premium&Houseware Exhibition(hereinafter referred to as Beijing Gift&Home)was held at the China International Exhibition Center(Chaoyang Pavilion...From August 14 to 16,the 52nd China Beijing International Gifts,Premium&Houseware Exhibition(hereinafter referred to as Beijing Gift&Home)was held at the China International Exhibition Center(Chaoyang Pavilion)in Beijing,China.As the annual grand finale of the northern gift industry.展开更多
悦读·明其义.An endless journey:The eternal quest for science.无尽的征程:科学的永恒探索.Science represents humanity's most organized attempt to comprehend the mysteries of our universe,which is built upon the ...悦读·明其义.An endless journey:The eternal quest for science.无尽的征程:科学的永恒探索.Science represents humanity's most organized attempt to comprehend the mysteries of our universe,which is built upon the work of countless gifted individuals.Many renowned researchers began their careers as laboratory assistants before becoming outstanding experts in charge of major scientific initiatives that shape our modern world.展开更多
Dunhuang UNESCO Global Geopark Nestled in northwest China’s Gansu Province,Dunhuang UNESCO Global Geopark is a mesmerising fusion of extraordinary geological formations,rich history,and breathtaking desert landscapes...Dunhuang UNESCO Global Geopark Nestled in northwest China’s Gansu Province,Dunhuang UNESCO Global Geopark is a mesmerising fusion of extraordinary geological formations,rich history,and breathtaking desert landscapes.Spanning 2,180.75 square km,the geopark encompasses iconic sites such as the Yardang landforms,Mingsha Mountain(Singing Sand Dunes),and Crescent Spring,alongside cultural treasures like the Mogao Grottoes and various ancient Silk Road relics.展开更多
研究所用60个家系的吉富品系尼罗罗非鱼(GIFT strain Nile tilapia,Oreochromis niloticus;简称吉富罗非鱼)样本均为由世界渔业中心所在地马来西亚引进的原种。采用传统形态学测量方法,测量每尾鱼的体质量、体长、体高、体宽、头长、尾...研究所用60个家系的吉富品系尼罗罗非鱼(GIFT strain Nile tilapia,Oreochromis niloticus;简称吉富罗非鱼)样本均为由世界渔业中心所在地马来西亚引进的原种。采用传统形态学测量方法,测量每尾鱼的体质量、体长、体高、体宽、头长、尾柄长和尾柄高后进行主成分分析和相关分析,研究吉富品系尼罗罗非鱼群体内的形态差异。结果显示,吉富罗非鱼体高与体质量的相关性最大(R2=0.9002)。在体长与体质量对应的点状分布中,总群体、雌雄群体和每个家系群体中均呈现出2条带状,分布于2条带的个体间质量差异不显著(P>0.05),对应的个体数量之比接近常数0.7;体高、体宽、头长、尾柄长和尾柄高相应的分布则呈现出变异幅度迥异的条带。本研究表明,吉富罗非鱼群体内部在形态上存在差异。展开更多
The NEW GIFT Nile tilapia （Oreochromis niloticus niloticus L.） is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new...The NEW GIFT Nile tilapia （Oreochromis niloticus niloticus L.） is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new variety has been extended in most of areas of China. The management of genetically improved strains, including the genetic markers for identification is needed urgently. RAPD analysis was conducted and their conversion to SCAR markers was developed. From NEW GIFT Nile tilapia, two strain-specific RAPD bands, S304624 bp and S36568 bp were identified. The strain-specific RAPD bands were gel-purified, cloned, and sequenced. Locus-specific primers were then designed to amplify the strain-specific bands. PCR amplification was conducted to test the variations in allele frequencies of two converted SCAR markers among the NEW GIFT Nile tilapia and its base strains, as well as 7 additional farmed strains worldwide. The frequency of SCAR marker Ⅰ （553 bp） was 85.7% in NEW GIFT Nile tilapia, but 16.7% in the base strain. The frequency of SCAR marker Ⅱ （558 bp） was 91.4% in NEW GIFT Nile tilapia, but 0% 70% in the 7 other strains. In order to confirm the utility of these two markers, an examination was conducted for a wild population from Egypt, resulted the frequency of SCAR Ⅰ and Ⅱ was 10% and 70%, respectively, much lower than that of New GIFT strain. The increase in allele frequency of these two SCAR markers suggests that these markers might be genetically linked to the quantitative trait loci （QTL） underlining the performance traits by long term selection, and indicate the bright potential of SCAR marker technology for tracking generations during selection progress and for distinguishing among genetically improved strain and other strains.展开更多
借助扫描电镜和透射电镜对尼罗罗非鱼（Oreochromis niloticus）、奥利亚罗非鱼（O.aureus）、奥尼罗非鱼（O.niloticus×O.aureus）和吉富罗非鱼（GIFT Strain in Nile Tilapia,O.niloticus）成熟精子的超微结构进行了比较研究。...借助扫描电镜和透射电镜对尼罗罗非鱼（Oreochromis niloticus）、奥利亚罗非鱼（O.aureus）、奥尼罗非鱼（O.niloticus×O.aureus）和吉富罗非鱼（GIFT Strain in Nile Tilapia,O.niloticus）成熟精子的超微结构进行了比较研究。结果显示,4种罗非鱼精子均为有鞭毛精子,无顶体,尾部轴丝9±2型。尼罗罗非鱼精子植入窝陷入核深度最浅,线粒体个数和平均直径分别为5-9个、（0.36±0.10）μm,鞭毛侧鳍平均翼长为（0.29±0.11）μm;奥利亚罗非鱼精子核内染色质着色程度最深,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为3-10个、（0.40±0.17）μm,鞭毛侧鳍平均翼长为（0.32±0.12）μm;奥尼罗非鱼精子核内染色质着色程度较浅,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为5-7个、（0.32±0.09）μm,鞭毛侧鳍平均翼长（0.26±0.09）μm;吉富罗非鱼精子核内染色质着色最浅,植入窝陷入核最深,约占2/3,线粒体个数和平均直径分别为5-10个、（0.37±0.08）μm,中段存在大量中空囊泡,鞭毛侧鳍平均翼长为（0.15±0.03）μm,与其它三种罗非鱼精子鞭毛平均侧鳍翼长比较具显著性差异（P〈0.05）。展开更多
文摘Exchanging gifts at the holidays is a tradition that dates back to thousands of years ago.Children are typically excused from buying gifts because they cost money kids may not have.But the truth is that some of the best gifts don't cost anything.If you would like to give meaningful gifts to family or friends at the holidays—without having to spend money—here's how you can get started.
文摘Even when kids dont realize it,teachers listen with their ears and their hearts.So many teachers dedi-cate their lives to education and helping us raise good kids.Some of them go so far above and beyond the call of duty that it makes you wonder if they are really angels in disguise.Stacy Caldwell is one of those teachers.
文摘The 51st China Beijing International Gifts,Premium and Houseware Exhibition(hereinafter referred to as the Gifts Exhibition) officially opened the kaleidoscope of creative gifts at China International Exhibition Center (Chaoyang Pavilion) on March 20th.More than 900 exhibitors built an aesthetic corridor of quality life with 200,000 gifts.
文摘From August 14 to 16,the 52nd China Beijing International Gifts,Premium&Houseware Exhibition(hereinafter referred to as Beijing Gift&Home)was held at the China International Exhibition Center(Chaoyang Pavilion)in Beijing,China.As the annual grand finale of the northern gift industry.
文摘Yesterday I lost my favorite watch.It was a gift from my grandfather.I was so sad and worried.I looked for it here and there,but I just couldn't find.
文摘悦读·明其义.An endless journey:The eternal quest for science.无尽的征程:科学的永恒探索.Science represents humanity's most organized attempt to comprehend the mysteries of our universe,which is built upon the work of countless gifted individuals.Many renowned researchers began their careers as laboratory assistants before becoming outstanding experts in charge of major scientific initiatives that shape our modern world.
文摘Dunhuang UNESCO Global Geopark Nestled in northwest China’s Gansu Province,Dunhuang UNESCO Global Geopark is a mesmerising fusion of extraordinary geological formations,rich history,and breathtaking desert landscapes.Spanning 2,180.75 square km,the geopark encompasses iconic sites such as the Yardang landforms,Mingsha Mountain(Singing Sand Dunes),and Crescent Spring,alongside cultural treasures like the Mogao Grottoes and various ancient Silk Road relics.
文摘研究所用60个家系的吉富品系尼罗罗非鱼(GIFT strain Nile tilapia,Oreochromis niloticus;简称吉富罗非鱼)样本均为由世界渔业中心所在地马来西亚引进的原种。采用传统形态学测量方法,测量每尾鱼的体质量、体长、体高、体宽、头长、尾柄长和尾柄高后进行主成分分析和相关分析,研究吉富品系尼罗罗非鱼群体内的形态差异。结果显示,吉富罗非鱼体高与体质量的相关性最大(R2=0.9002)。在体长与体质量对应的点状分布中,总群体、雌雄群体和每个家系群体中均呈现出2条带状,分布于2条带的个体间质量差异不显著(P>0.05),对应的个体数量之比接近常数0.7;体高、体宽、头长、尾柄长和尾柄高相应的分布则呈现出变异幅度迥异的条带。本研究表明,吉富罗非鱼群体内部在形态上存在差异。
基金National Tilapia Industry Technical System(nycytx-48-3)National Tilapia Seed Program(nyhyzx07-044-01)
文摘The NEW GIFT Nile tilapia （Oreochromis niloticus niloticus L.） is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new variety has been extended in most of areas of China. The management of genetically improved strains, including the genetic markers for identification is needed urgently. RAPD analysis was conducted and their conversion to SCAR markers was developed. From NEW GIFT Nile tilapia, two strain-specific RAPD bands, S304624 bp and S36568 bp were identified. The strain-specific RAPD bands were gel-purified, cloned, and sequenced. Locus-specific primers were then designed to amplify the strain-specific bands. PCR amplification was conducted to test the variations in allele frequencies of two converted SCAR markers among the NEW GIFT Nile tilapia and its base strains, as well as 7 additional farmed strains worldwide. The frequency of SCAR marker Ⅰ （553 bp） was 85.7% in NEW GIFT Nile tilapia, but 16.7% in the base strain. The frequency of SCAR marker Ⅱ （558 bp） was 91.4% in NEW GIFT Nile tilapia, but 0% 70% in the 7 other strains. In order to confirm the utility of these two markers, an examination was conducted for a wild population from Egypt, resulted the frequency of SCAR Ⅰ and Ⅱ was 10% and 70%, respectively, much lower than that of New GIFT strain. The increase in allele frequency of these two SCAR markers suggests that these markers might be genetically linked to the quantitative trait loci （QTL） underlining the performance traits by long term selection, and indicate the bright potential of SCAR marker technology for tracking generations during selection progress and for distinguishing among genetically improved strain and other strains.
文摘借助扫描电镜和透射电镜对尼罗罗非鱼（Oreochromis niloticus）、奥利亚罗非鱼（O.aureus）、奥尼罗非鱼（O.niloticus×O.aureus）和吉富罗非鱼（GIFT Strain in Nile Tilapia,O.niloticus）成熟精子的超微结构进行了比较研究。结果显示,4种罗非鱼精子均为有鞭毛精子,无顶体,尾部轴丝9±2型。尼罗罗非鱼精子植入窝陷入核深度最浅,线粒体个数和平均直径分别为5-9个、（0.36±0.10）μm,鞭毛侧鳍平均翼长为（0.29±0.11）μm;奥利亚罗非鱼精子核内染色质着色程度最深,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为3-10个、（0.40±0.17）μm,鞭毛侧鳍平均翼长为（0.32±0.12）μm;奥尼罗非鱼精子核内染色质着色程度较浅,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为5-7个、（0.32±0.09）μm,鞭毛侧鳍平均翼长（0.26±0.09）μm;吉富罗非鱼精子核内染色质着色最浅,植入窝陷入核最深,约占2/3,线粒体个数和平均直径分别为5-10个、（0.37±0.08）μm,中段存在大量中空囊泡,鞭毛侧鳍平均翼长为（0.15±0.03）μm,与其它三种罗非鱼精子鞭毛平均侧鳍翼长比较具显著性差异（P〈0.05）。
