Amino acid composition and functional properties of giant red sea cucumber (Parastichopus californicus) collagen hydrolysates

Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis.The aim of this study was to evaluate the functional properties of collagen hydrolysates from this species.The degree of hydrolysis (DH),amino acid composition,SDS-PAGE,emulsion activity index (EAI),emulsion stability index (ESI),foam expansion (FE),and foam stability (FS) of hydrolysates were investigated.The effects of pH on the EAI,ESI FE and FS of hydrolysates were also inves-tigated.The results indicated that the β and α1 chains of the collagen were effectively hydrolyzed by trypsin at 50℃ with an En-zyme/Substrate (E/S) ration of 1:20 (w:w).The DH of collagen was up to 17.3% after 3 h hydrolysis with trypsin.The hydrolysates had a molecular weight distribution of 1.1 17 kDa,and were abundant in glycine (Gly),proline (Pro),glutamic acid (Glu),alanine (Ala) and hydroxyproline (Hyp) residues.The hydrolysates were fractionated into three fractions (< 3 kDa,3 10 kDa,and > 10 kDa),and the fraction of 3 10 kDa exhibited a higher EAI value than the fraction of > 10 kDa (P<0.05).The fraction of > 10 kDa had higher FE and FS values than other fractions (P<0.05).The pH had an important effect on the EAI,ESI,FE and FS.All the fractions showed undesirable emulsion and forming properties at pH 4.0.Under pH 7.0 and pH 10.0,the 3 10 kDa fraction showed higher EAI value and the fraction of > 10 kDa showed higher FE value,respectively.They are hoped to be utilized as functional ingredients in food and nutraceutical industries.     

The lost city of north‐west Queensland: a test of the model of giant Grikeland development in semi‐arid Karst

Jennings and Sweeting's (1963) model of landscape evolution in the Limestone Ranges of Western Australia has been proposed as a general scheme of semi‐arid karstification by Williams (1978) and Ford and Williams (1989). The model involves an initial plateau surface which undergoes progressive karstic dissection. The resultant landscape is characterised first by giant grikelands, then by box valleys and finally by karst towers. The depth of dissection is governed by the altitude of successive levels of pediplanation adjacent to the karst, with each karst level representing the location of a former erosion surface. The Lost City, a giant grikeland in the Barkly karst of north‐west Queensland, has evolved by the karstic dissection and stripping of a gently dipping sequence of carbonates and cherts. By contrast with the type example, the depth of dissection, the altitude of successive surfaces, the form and even the location of the grikeland are all controlled by rock structure. Not only does this cast doubt on the general applicability of Jennings and Sweeting's model, it suggests that such landscapes may also be the result of structural control and that the role played by semi‐arid climates may be less important than has previously been proposed. Given our present poverty of knowledge of semi‐arid karstification, any attempt to identify type examples of semi‐arid karst may be premature.     

特大多期复合型滑坡稳定性评价及因素敏感性分析

对西南某水电站库区一特大型、多期复合型滑坡所处的工程环境条件、自身结构及物质组成特征等进行了认真调查和研究。通过定性分析和定量评价，对滑坡整体及分期稳定性进行了综合评价。同时，根据实际情况，对滑坡稳定性影响因素进行了敏感性分析。     

气候变化对四川大熊猫栖息地的影响

利用累积距平曲线分析方法、一元线性回归分析、二项式系数加权平均法,通过分析大熊猫分布区域34个气象站建站以来的温度、降水量、日照时数、相对湿度气象观测资料,研究气候变化对大熊猫栖息地的影响,得出干暖是大熊猫栖息地气候变化的总体趋势。     

DISTRIBUTION FEATURES OF GIANT SEA-SALT NUCLEI IN ATMOSPHERE OVER YONGXING ISLAND, XISHA ISLANDS,DURING NORTHEAST WINTER MONSOON

In this paper, the chlorine ions nuclei data, observed at Yongxing (Xisha Islands) during November 1987, are analyzed. The main results are:1) The average concentration of chiorine ions nuclei with dry diameters larger than 2 μm is 878 per litre and the average salt content is 105. 4μg/m³, in which special giant nuclei with dry diameters larger than 4 μm are 19O per litre. The largest dry diameter of chloride ions observed reaches 57 μm, which are larger than that observed there during the southwest summer monsoon. The spetrum type shows quasi-unimodal and exponential lapse. 2) The salt content decreases with the height over sea surface. 3) The concentrations of chlorine ions nuclei reach the maximum value at 0800 (Local time, same below). and minimum at 0200.     

Seismic sentinel? An analysis of captive giant panda behavior in response to the Lushan earthquake in China

It is widely believed that various animal species can sense and respond to the geophysical stimuli that precede earthquakes, especially electromagnetic fields, although supporting field evidence is mostly anecdotal. Here we report on the reactions of four female giant pandas under observation over the three days prior to the Lushan (30.1°N, 103.0°E) magnitude 7.0 earthquake that occurred in Sichuan province, China, on April 20, 2013. We observed no significant generalized behavioral anomalies indicative of them perceiving an impending earthquake. We also observed no startle behaviors in the 5 s prior to tremors commencing, indicating that these pandas either did not detect or did not respond to precursor P-waves. Our findings suggest that although giant pandas have evolved in, and continue to occupy exclusively, a seismically active range in central China, they do not appear to perceive pre-earthquake geophysical warning signs.     

Diet of giant kokopu,Galaxias argenteus

The stomach contents of 105 preserved specimens of giant kokopu, Galaxias argenteus (Gmelin 1789), collected from various locations around New Zealand between c. 1963 and 1994, were used to investigate giant kokopu diet. A total of 76 food taxa, predominantly invertebrates, were identified and categorised as either of aquatic or terrestrial origin from the 91 stomachs that contained food items. Aquatic Trichoptera, Gastropoda, and Hemiptera comprised 29.1, 12.6, and 14.4% by abundance respectively, and terrestrial Coleoptera 12.2% by abundance. Adult terrestrial Coleoptera were the most commonly occurring taxa, and were found in 59% of the stomachs that contained food. Food items of aquatic origin occurred in 94.5% of the giant kokopu stomachs that contained food and comprised 74.9% of the items by abundance. Although fewer items of terrestrial origin were encountered, they nevertheless appeared to be a significant component of the diet, and occurred in 83.5% of the giant kokopu stomachs that contained food, and comprised 25.1% of the items by abundance. Items of terrestrial origin occurred slightly more frequently in giant kokopu from lotic habitats than from lentic habitats. The significance of terrestrial food may be associated with giant kokopu preference for habitats with riparian cover. Fish also appeared to be a significant component of the diet, as 26% of the giant kokopu examined contained fish remains. Giant kokopu are probably best described as generalist feeders, as they utilise a wide range of foods of both aquatic and terrestrial origin.     

黄、东海水母质点追踪影响因素分析

基于数值模型采用质点追踪的方法对大型水母的运移规律及其聚集的影响因素进行了研究。本文共设置6个质点释放区,分别从3、4、5月1日释放后追踪至9月30日。主要结论有:(1)采用不含潮汐过程与包含潮汐过程的水动力模式分别对表层质点进行追踪,结果表明含潮汐混合和潮汐非线性效应的POM模式对质点时空分布的模拟较为可靠;(2)基于含潮汐过程的POM模式气候态模拟结果,考虑质点垂直运动进行追踪,质点运移速度较表层追踪大大减慢,进入朝鲜/对马海峡的质点减少;其中济州岛沿岸质点几乎全部穿过朝鲜/对马海峡进入日本海,其它释放区质点最终广泛分布在南黄海以及东海中陆架,主要在黄海潮汐锋区和长江口以南沿岸锋聚集;(3)通过分析不同释放时间对质点在9月末分布的影响发现,质点释放时间偏早,即水母幼体形成较早,将使相对较多的质点向朝鲜/对马海峡聚集。     

星系形成环境与宇宙中的空洞

本文讨论了初始扰动谱中大尺度负密度扰动对星系尺度扰动峰值的局域密度的影响，以及空洞演化中边界壳层非线性发展的作用。结果表明它们并不能解释空洞的形成。但考虑星系相互作用在可见星系形成中的关键作用，把星系群与星系团的存在作为形成的必要条件时，可以用负密度扰动对星系团和星系群的局域密度的调制，解释３０─６０Ｍｐｃ的空洞形成。对于更大尺度空洞的形成，则必须考虑对标准冷暗物质模型谱作出修正。     

胶东金矿深部找矿主要成果和关键理论技术进展

系统总结了胶东金矿深部找矿的主要成果,回顾了胶东金矿的主要找矿理论认识和找矿方法技术发展历程。目前,胶东地区深、浅部累计探明金矿资源储量超过4500t,其中,500~2000m深度的深部金资源储量逾2700t,单矿床规模大于等于100t的超大型金矿床累计资源储量超过2900t,以破碎带蚀变岩型为主的金矿床资源储量逾3900t。探明了千吨级焦家巨型金矿床和三山岛巨型金矿床。对成矿模式的认识,经历了从受小构造控制的石英脉型金矿到受区域性大断裂控制的蚀变岩型金矿,再到深部阶梯式成矿的逐步扩展的发展过程。对成矿机制的认识,由绿岩带型金矿、多源长期成矿、岩浆热液金矿、幔源成矿、造山型金矿等发展为热隆伸展成矿。对矿床类型的认识,综合焦家式破碎带蚀变岩型金矿、玲珑式石英脉型金矿及其他多种类型金矿认识,提出了胶东型金矿的概念。找矿方法技术由早期的常规方法技术,发展为现今的高精度、大探测深度找矿方法技术。