中间球海胆(♀)与光棘球海胆(♂)种间杂交及自繁后代生长与表型特征比较

为了解中间球海胆Strongylocentrotus intermedius(Si)与光棘球海胆Strongylocentrotus nudus(Sn)杂交后代的杂种优势及表型特征,以同期培育的中间球海胆(♀)与光棘球海胆(♂)种间杂交子一代(Si♀×Sn♂)幼胆及自繁子一代幼胆为研究对象,对3种海胆的成活率、生长表现(生长速度和表型变异)和表型特征(管足色素细胞数量、骨片形状、棘刺的颜色和长度)进行了比较。结果表明:经过90 d的养殖,中间球海胆和光棘球海胆的最终成活率均为100%,杂交海胆为97%,但3种海胆间无显著性差异(P>0.05);在0⁶0 d的养殖范围内,杂交海胆具有最快的特定生长率(4.00%/d),且显著高于中间球海胆(2.91%/d)和光棘球海胆(3.15%/d)(P<0.05),而后两者之间无显著性差异(P>0.05),6060 d的养殖范围内,杂交海胆具有最快的特定生长率(4.00%/d),且显著高于中间球海胆(2.91%/d)和光棘球海胆(3.15%/d)(P<0.05),而后两者之间无显著性差异(P>0.05),60⁹0 d时,3种海胆的特定生长率之间均无显著性差异(P>0.05);试验结束时,杂交海胆体质量的变异系数(76.12%)显著高于光棘球海胆(63.81%)和中间球海胆(52.05%)(P<0.05),表明种间杂交显著增加了后代的遗传变异;光棘球海胆管足中色素细胞数量最多,中间球海胆最少,杂交海胆的色素细胞数量介于父母本之间;杂交海胆棘刺为浅紫色,介于中间球海胆的白色和紫海胆的深紫色之间,而棘长较父母本细短;与棘色和管足颜色不同,杂交海胆骨片两端的突起产生了新的变异。研究表明,在幼胆期杂交海胆的表型特征明显区别于父母本,具有更快的生长速度和更高的变异水平,具有较高的育种价值。     

中间球海胆、光棘球海胆自繁和杂交后代幼体发育及对高温的反应

对中间球海胆Strongylocentrotus intermedius(Si)和光棘球海胆S.nudus(Sn)进行完全双列杂交,通过对自繁后代(Si♀×Si♂、Sn♀×Sn♂)和杂交子代(Si♀×Sn♂、Sn♀×Si♂)的幼体发育进行观察,详细描述了幼体发育各个阶段的形态特征,并在18、22、26、30℃4个温度下对自繁和杂交子代的受精率、孵化率、各幼体时期的畸形率和生长状况进行了测量和分析。结果表明:杂交海胆的受精率均显著低于自繁海胆(P<0.05),Si♀×Sn♂杂交海胆在18℃时的孵化率与自繁海胆无显著性差异(P>0.05);Si♀×Sn♂杂交海胆幼体形态融合了两种自繁幼体的特征;温度对光棘球海胆自繁和杂交海胆子代的受精率、孵化率均有显著影响(P<0.05),中间球海胆在22℃下的受精率和孵化率最高,而光棘球海胆的最适受精和孵化温度为18℃,Si♀×Sn♂杂交海胆最适受精温度为22℃,而最适孵化温度为18℃;温度对海胆幼体发育的畸形率和生长均有显著影响(P<0.05),3种海胆幼体的最适生长水温均为18℃,Si♀×Sn♂杂交海胆在四腕幼体时期的畸形率最低,体长最小,除在八腕幼体时期畸形率最高外,在六腕幼体和八腕幼体时期的畸形率和生长性状均是介于自繁幼体之间。研究表明,Si♀×Sn♂杂交海胆在胚胎发育早期具有母本的热耐受性和生长劣势,但是随着幼体的生长发育,母性效应逐渐减弱,其在生长方面逐渐体现出父本的生长优势。     

中间球海胆与马粪海胆杂交后代幼胆期耐热性研究

为探明中间球海胆Strongylocentrotus intermedius(Si)和马粪海胆Hemicentrotus pulcherrimus(Hp)杂交后代(Si♀×Hp♂和Hp♀×Si♂)的耐热性能,分别对两亲本及其正反交后代的幼海胆进行了快速升温试验,通过观察生存状态并测量生存时间,比较了两亲本及其正反交后代幼胆期的耐热指数(Upper thermal tolerance, UTT)差异,并计算了两种杂交海胆生长早期在耐热指数上的杂种优势。结果表明:在快速升温条件下,4种海胆开始死亡时的温度由高到低依次为Hp(31.5℃)、Hp♀×Si♂(30℃)、Si♀×Hp♂(29.5℃)和Si(28℃),杂交后代Hp♀×Si♂和Si♀×Hp♂分别较中间球海胆高2、1.5℃,分别较马粪海胆低1.5、2℃;生存分析表明,总体生存时间分布由长至短依次为Hp、Hp♀×Si♂、Si♀×Hp♂和Si,4种海胆生存时间两两间均存在极显著性差异(P<0.01);4种海胆的耐热指数由高到低依次为Hp(6864.44℃·h)、Hp♀×Si♂(4955.42℃·h)、Si♀×Hp♂(4136.46℃·h)和Si(1167.42℃·h),不同种类的耐热指数相互之间均存在显著性差异(P<0.05);杂交后代Hp♀×Si♂和Si♀×Hp♂在耐热指数上分别表现出23.39%和3.00%的中亲杂种优势;两种杂交后代虽然相较于马粪海胆分别表现出-39.74%～-27.81%的单亲杂种劣势,但相较于中间球海胆均表现出254.23%～324.37%的单亲杂种优势。研究表明,中间球海胆与马粪海胆正反交后代均可作为培育耐高温海胆新品种的候选种类。     

中间球海胆繁殖前后性腺中脂类和脂肪酸含量变化

为研究中间球海胆Strongylocentrotus intermedius繁殖前后性腺中脂类和脂肪酸含量的变化,采用毛细管气相色谱法对排精/卵前后的中间球海胆性腺中脂类和脂肪酸组成进行了分析比较。结果表明:中间球海胆排精/卵前,雌、雄个体在性腺指数和性腺含水率上无显著性差异(P>0.05),雌性个体性腺中脂类含量显著高于雄性个体(P<0.05);排精/卵前后,海胆性腺中磷脂含量均较高,是海胆脂类的重要组分,排精/卵后,海胆性腺中游离脂肪酸和甘油三酯显著下降(P<0.05),胆固醇在雌性性腺中出现了显著升高(P<0.05);雌、雄海胆性腺中脂肪酸组成种类基本相同,共检测到24种脂肪酸,其中C_(20∶4(n-6))和C_(20∶5(n-3))是主要的不饱和脂肪酸组分,排精/卵后,雄性个体性腺中C_(18∶1(n-9))含量显著升高(P<0.05),雌性个体C_(18∶0)含量显著升高(P<0.05)。本研究结果可为海胆亲本营养繁殖学的研究提供基础数据和理论依据。     

中间球海胆与紫海胆种间杂交的受精、孵化和幼体发育研究

为探明中间球海胆Strongylocentrotus intermedius(Si)与紫海胆Anthocidaris crassispina(Ac)种间杂交的受精、孵化和幼体发育规律,对中间球海胆和紫海胆进行种间杂交,检测了不同水温和精子种类对海胆受精卵卵径、受精率和孵化率的影响,并对自繁和杂交海胆幼体发育时间和体长进行了测定和比较。结果表明:受精前中间球海胆卵径(86.64μm±4.21μm)极显著小于紫海胆(95.62μm±3.80μm)(P<0.01);在21℃和24℃下,自交组Si♀×Si♂受精卵卵径显著或极显著大于杂交组Si♀×Ac♂(P<0.05或P<0.01),而杂交组Ac♀×Si♂和自交组Ac♀×Ac♂受精卵卵径则不受水温(24℃和26℃)的影响;相同温度下,种间杂交受精率均极显著低于自繁受精率(P<0.01),Si♀×Si♂组(或Si♀×Ac♂组)受精率在21℃和24℃下无显著性差异(P>0.05),而杂交组Ac♀×Si♂在26℃下的受精率极显著高于24℃下(分别为38.91%±8.25%和0.79%±1.11%)(P<0.01);杂交组Si♀×Ac♂在21℃下的孵化率(87.96%±4.18%)极显著低于自交组Si♀×Si♂(99.64%±0.81%)(P<0.01),而在24℃下,这两组海胆均不能孵化,杂交组Ac♀×Si♂在24℃下的孵化率(9.32%±4.33%)极显著低于自交组Ac♀×Ac♂(100%)(P<0.01),而在26℃下则不能孵化;Ac♀×Ac♂组和Ac♀×Si♂组在24℃下经5 d即可发育至八腕幼体,Si♀×Ac♂组在21℃下经9 d发育至八腕幼体,Si♀×Si♂在21℃下经12 d发育至八腕幼体。研究表明,杂交组Si♀×Ac♂适宜在24℃下受精,21℃下孵化,而杂交组Ac♀×Si♂则适宜在26℃下受精,24℃下孵化,杂交组Ac♀×Si♂可能更具备高温耐受能力,可作为耐高温品种培育的重点材料进行进一步研究。     

中间球海胆幼体及稚海胆生长性状的遗传参数估计

为估计中间球海胆Strongylocentrotus intermedius幼体及稚海胆生长性状的遗传参数,采用巢式不平衡设计方法建立了44个中间球海胆全同胞家系,并测量了各家系海胆四腕幼体、六腕幼体和八腕幼体等各期浮游幼体的体长以及受精后30 d的稚海胆壳径,采用动物模型和约束性最大似然法(REML)估计了中间球海胆幼体和稚海胆生长性状的遗传参数。结果表明:中间球海胆四腕幼体和八腕幼体体长的遗传力分别为0.705±0.373和0.538±0.444,为高度遗传力,六腕幼体体长和稚海胆壳径的遗传力均接近于0,为低度遗传力;各阶段幼体体长和稚海胆壳径的共同环境效应为0.048⁰.352;各阶段幼体体长间遗传相关为正相关(0.3000.352;各阶段幼体体长间遗传相关为正相关(0.300⁰.518),各阶段幼体体长与稚海胆壳径间的遗传相关为负相关(-0.1520.518),各阶段幼体体长与稚海胆壳径间的遗传相关为负相关(-0.152^-0.435)。本研究结果可为制定中间球海胆的早期选择和间接选择选育方案提供参考依据。     

六种海胆及四种杂交海胆管足骨片类型和数量

为研究不同种类海胆Echinoidea管足内骨片类型和数量,利用光学显微镜对6种海胆(中间球海胆Strongylocentrotus intermedius、紫海胆Anthocidaris crassispina、光棘球海胆Mosecentrotus nudus、海刺猬Glyptocidaris crenularis、高腰海胆Mespilia globulus、马粪海胆Hemicentrotus pulcherrimus)及4种杂交海胆(中间球海胆♀×紫海胆♂S.intermedius♀×A.crassipine♂、中间球海胆♀×马粪海胆♂S.intermedius♀×H.pulcherrimus♂、中间球海胆♂×马粪海胆♀S.intermedius♂×H.pulcherrimus♀、中间球海胆♀×光棘球海胆♂S.intermedius♀×A.crassipine♂)管足的骨片进行了观察统计并分析。结果表明:10种海胆共有C形体、S形体、杆状体、三叉形体、海马状体5种骨片类型,且不同种海胆骨片类型和数量存在显著性差异;杂交海胆未产生新的骨片类型,拥有双亲的部分骨片类型,在骨片数量上倾向于双亲的平均值。研究表明,利用海胆管足内骨片类型和数量可完全区分出这10种海胆,本研究结果可为海胆分类提供理论依据,也可为杂交种的鉴定提供参考。     

中间球海胆幼体及稚海胆生长性状的遗传参数估计

为估计中间球海胆Strongylocentrotus intermedius幼体及稚海胆生长性状的遗传参数,采用巢式不平衡设计方法建立了44个中间球海胆全同胞家系,并测量了各家系海胆四腕幼体、六腕幼体和八腕幼体等各期浮游幼体的体长以及受精后30 d的稚海胆壳径,采用动物模型和约束性最大似然法(REML)估计了中间球海胆幼体和稚海胆生长性状的遗传参数。结果表明:中间球海胆四腕幼体和八腕幼体体长的遗传力分别为0.705±0.373和0.538±0.444,为高度遗传力,六腕幼体体长和稚海胆壳径的遗传力均接近于0,为低度遗传力;各阶段幼体体长和稚海胆壳径的共同环境效应为0.048~0.352;各阶段幼体体长间遗传相关为正相关(0.300~0.518),各阶段幼体体长与稚海胆壳径间的遗传相关为负相关(-0.152~-0.435)。本研究结果可为制定中间球海胆的早期选择和间接选择选育方案提供参考依据。     

六种海胆及四种杂交海胆管足骨片类型和数量

为研究不同种类海胆Echinoidea管足内骨片类型和数量,利用光学显微镜对6种海胆(中间球海胆Strongylocentrotus intermedius、紫海胆Anthocidaris crassispina、光棘球海胆Mosecentrotus nudus、海刺猬Glyptocidaris crenularis、高腰海胆Mespilia globulus、马粪海胆Hemicentrotus pulcherrimus)及4种杂交海胆(中间球海胆♀×紫海胆♂S.intermedius♀×A.crassipine♂、中间球海胆♀×马粪海胆♂S.intermedius♀×H.pulcherrimus♂、中间球海胆♂×马粪海胆♀S.intermedius♂×H.pulcherrimus♀、中间球海胆♀×光棘球海胆♂S.intermedius♀×A.crassipine♂)管足的骨片进行了观察统计并分析。结果表明:10种海胆共有C形体、S形体、杆状体、三叉形体、海马状体5种骨片类型,且不同种海胆骨片类型和数量存在显著性差异;杂交海胆未产生新的骨片类型,拥有双亲的部分骨片类型,在骨片数量上倾向于双亲的平均值。研究表明,利用海胆管足内骨片类型和数量可完全区分出这10种海胆,本研究结果可为海胆分类提供理论依据,也可为杂交种的鉴定提供参考。     

不同饵料模式与投喂方式对中间球海胆性腺营养成分的影响

在实验室条件下,进行了不同饵料模式与投喂方式对中间球海胆Strongylocentrotus intermedius性腺营养成分的影响研究。试验设置4种饵料模式(M1组投喂海带,M2组投喂海带+贻贝,M3组投喂南瓜,M4组投喂胡萝卜)和3种投喂方式(对照组投喂海带150 d,RM1组投喂南瓜75 d后投喂海带75 d,RM2组投喂胡萝卜75 d后投喂海带75 d),试验结束后,对海胆性腺中氨基酸、β-胡萝卜素和脂肪酸含量进行测定。结果表明:不同饵料模式条件下,M2组海胆性腺中氨基酸总量(TAA)、必需氨基酸总量(EAA)和EAA/TAA均最高;M4组鲜味氨基酸总量占氨基酸总量的百分比最高;M1与M2组雌、雄海胆的β-胡萝卜素含量及个体平均β-胡萝卜素含量均无差异性差异(P>0.05),二者显著高于其他2组(P<0.05);M3组雌海胆性腺中多不饱和脂肪酸(PUFA)含量显著高于其他3组(P<0.05),雄海胆中PUFA含量4组间无显著性差异(P>0.05)。不同投喂方式条件下,RM2组海胆性腺中TAA、EAA和EAA/TAA含量均最高;对照组雄海胆性腺中β-胡萝卜素含量及个体平均β-胡萝卜素含量均显著高于RM1和RM2组(P<0.05),而雌海胆性腺中二者的含量与RM1组无显著性差异(P>0.05),但均显著高于RM2组(P<0.05);RM1组雌、雄海胆性腺中PUFA含量均最高。研究表明:M2组饵料模式和RM2组投喂方式均可提高海胆性腺中氨基酸含量,且M2组饵料模式对海胆个体平均β-胡萝卜素含量的提高有促进作用,M3组饵料模式和RM1组投喂方式可明显提高海胆性腺中PUFA的含量。     

Vanadium in foods and in human body fluids and tissues

Using neutron activation analysis, vanadium was analysed in a range of foods, human body fluids and tissues. On the basis of these results and those of other workers, it was concluded that daily dietary intake amounts to some tens of micrograms. Analysis of body fluids (including milk, blood and excreta) and organs and tissues provided an estimate for the total body pool of vanadium in man of about 100 μg. Vanadium was not detectable in blood and urine at the level of 0.3 ng/g, while low levels were found in muscle, fat, bone, teeth and other tissues. The relationship between dietary intake to pulmonary absorption is discussed in relation to the occurrence of vanadium in man-made air particulates. The very low levels found in milks and eggs suggest minimal vanadium requirements in growth. The findings are discussed in the light of previous results and also in relation to the possible essentiality of vanadium.     

Iodine-129 in thyroid and urine in Ukraine and Denmark

Human thyroids collected from Gomel in Belarus, sheep thyroid from Jutland and human urine from Zealand in Denmark were analysed for 129I and 127I concentrations. The ratios of 129I/127I in human thyroid in Gomel are 2.65-11.0 x 10(-9) with an average of 7.21 x 10(-9), which is one order of magnitude higher than those from Asia and South America (10(-10)), but significantly lower than those observed in west Europe (10(-8)). A weak negative correlation (P < 0.05) between 129I/127I ratio in human thyroid and the age of the subjects was observed in Gomel. The average ratio of 129I/127I in sheep thyroids from Jutland of Denmark is 1.81 x 10(-7), which is two orders of magnitude higher than those in south hemisphere, and Asia. It is also significantly higher than those observed in other west European countries before 1984 and that in human thyroid in Gomel. The high thyroid 129I level in Jutland is attributed to the release of reprocessing plants in France and UK. The 129I/127I ratios in human urine in Zealand of Denmark are 0.86-2.86 x 10(-8). The possibility of using urine 129I to evaluate the thyroid exposure to 129I is investigated.     

儿童青少年近视的防控研究进展

儿童青少年近视率一直处于高位并持续上升,严重影响了我国儿童青少年的学习和生活,本研究通过查阅国内外治疗儿童青少年近视相关著作及文献,针对目前儿童青少年近视防控手段的进展,对各治疗方案进行分析和研究。     

Lead and cadmium contents in cereals and pulses in north-eastern China

It is known that, unlike Japanese, Koreans or southern Chinese who depend on rice as a major source of energy for daily life, people in north-eastern China rely not only on rice, but on wheat and other cereals and to a lesser extent also on pulses. Cereal and pulse samples were collected from open markets in north-eastern China, and analyzed by inductively-coupled plasma spectrometry (ICP-MS) for two potentially hazardous heavy metals — lead (Pb) and cadmium (Cd). The average Pb level in cereals (31.3 ng Pb/g as a geometric mean) and that of pulses (25.7 ng Pb/g) were similar to each other with no significant difference. Among the cereals, Pb contents were higher in foxtail millet (54.3 ng/g) and lower in maize (35.4 ng Pb/g; grain and flour in combination), wheat flour (28.8 ng Pb/g) and rice flour (22.7 ng Pb/g). Lead levels in two important types of pulses, kidney bean and soybean (24.6 and 30.8 ng Pb/g, respectively), were comparable to the levels in rice and wheat. In contrast, Cd levels were substantially higher in pulses (55.7 ng Cd/g) than in cereals (9.2 ng Cd/g), and among the pulses, Cd in soybean (55.7 ng Cd/g) was significantly higher than that in kidney bean (23.8 ng Cd/g). The possible public health implication of the Pb and Cd levels, especially the high Pb level in foxtail millet (54.3 ng Pb/g) and the high Cd level in soybean (73.5 ng Cd/g), is discussed.     

德国城乡景观与中国景观问题

2003年,笔者获得德国DAAD(德国国际学术交流基金会)奖励资助,作为访问学者在德国逗留了4个月(4月～8月).在这期间,笔者还考察了法国、丹麦、瑞典和意大利,但我认为还是德国的景观最为优雅和美丽.     

广义文脉与规划设计教育

城市规划设计教育不仅应关注历史化,还应关注自然、社会和经济;不仅应关注地方和传统,还应关注全球和未来。城市规划教育应掌握正确的发展观和方法论,肩负起发展地万脉的历史使命,保护社会公众的利益,推动城市持续发展。     

Perchlorate in raw and drinking water sources in England and Wales

A well‐known use of perchlorate is as a rocket fuel propellant; however, more widespread uses include in munitions and fireworks, and it also occurs naturally. Perchlorate suppresses the thyroid, which can lead to a variety of adverse effects. It is a widespread contaminant in the United States, but limited occurrence data in the United Kingdom exist, and even less for drinking water. Monitoring of 20 raw and treated drinking water sites in England and Wales, covering four seasonal periods, showed that perchlorate is a low‐level background contaminant of raw and treated drinking water. Low concentrations (treated drinking water: <0.020–2.073 μg/L, mean 0.747 μg/L) were detected at every higher‐risk site. The concentrations were comparable in each of the four sampling exercises and no significant trends were apparent relating to the time of year, the type of risk or the method of chlorination. Limited data showed that removal by ion exchange and granular‐activated carbon may occur.     

创新创业教育在高校实践教学中的研究与探索

大学生创新创业教育的开展对高校人才培养体系的完善具有非常重要的意义。针对目前我国高校创新创业教育模式的问题与不足进行探讨,分析研究了创新创业教育的实质,最后重点阐述了在实践教学中如何加强创新思路的引导,建立有效激励机制,开展创新及创业教育的应对策略,促进对大学生实践创新能力、创业就业能力和持续发展能力的培养。     

武汉城市景观文化生态保护建设的问题与对策

城市文化生态是形成城市特色的文化要素。历史古迹,优秀建筑,空间形态,环境特色,作为城市文化生态的显现部分,既是城市文化底蕴直观生动的反映,也是市民的情感港湾和精神家园。理应得到珍惜和保护。该文在系统地概括武汉景观文化生态特点的基础上,重点分析了当前武汉城市景观规划建设中的文化生态问题,提出了武汉今后改进城市景观文化生态规划建设的对策建议。