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1.
  • 1. This paper reports on the dynamics of the coral community structure at A Ma Wan (AMW) and A Ye Wan (AYW) in Tung Ping Chau, Hong Kong, focusing on data collected before and after the summer typhoon seasons in 1997 to 1999. This period (1999) experienced the highest frequency of severe tropical cyclones to hit Hong Kong with one cyclone being the strongest to hit in the last 23 years (1984 to 2006).
  • 2. This is part of a long‐term monitoring programme of subtropical coral communities that has been set up in AMW since May 1997 and AYW since May 1998 with nine fixed position 40 m long transects and 0.5 m × 0.5 m permanent quadrats laid at 5 m intervals along each transect. A total of 45 scleractinian coral species from 21 genera (12 families) was recorded, with 40 species in AMW and 32 species in AYW recorded at the beginning of the study.
  • 3. Multidimensional scaling ordinations showed distinct spatial variations in the coral communities within and between sites. These variations were probably a result of the differential effects of the repeated cyclone impacts on the communities. Cyphastrea serailia, Goniopora lobata, Montipora peltiformis and Pavona decussata were the dominant species most strongly affected by cyclone impacts at AMW, experiencing a 6.2–16.2% loss of mean area cover during the study period. Some dominant species (e.g. P. decussata) in AYW also experienced a 6.5–14.3% loss of mean area cover within the same period.
  • 4. Overall, these coral community structures appeared relatively stable and resistant to repeated physical disturbances. However, they may have low resilience towards more severe disturbances in the future. Preserving the resilience of coral communities/species in Tung Ping Chau should be one of the main goals of coral conservation strategies for the island.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
2.
A water soluble storage albumin from Inca peanut (IPA) accounted for approximately 25% (w/w) of defatted seed flour weight, representing 31% of the total seed protein. IPA is a 3S storage protein composed of two glycosylated polypeptides, with estimated molecular weights (MW) of 32800 and 34800 Da, respectively. IPA has an estimated sugar content of 4.8% +/- 0.92% (n = 6). IPA is a basic protein (pI of approximately 9.4) and contains all of the essential amino acids in adequate amounts when compared to the FAO/WHO recommended pattern for a human adult. The tryptophan content of IPA is unusually high (44 mg/g of protein), whereas the phenylalanine content is low (9 mg/g of protein). IPA is a highly digestible protein in vitro.  相似文献   
3.
4.
Near extinction of a highly fecund fish: the one that nearly got away   总被引:6,自引:0,他引:6  
It is widely assumed that commercial fisheries of highly fecund species are particularly resilient to exploitation, and that, should populations become seriously diminished, economic constraints will force fishing to cease before biological extinction can occur. Indeed, among commercially exploited marine fishes there is not one confirmed global extinction. Here we document, using nonconventional means, a story that not only questions such assumptions but that should also alert us to how little we know about significant fisheries in some parts of the world. Our case study is that of the highly threatened Chinese bahaba, Bahaba taipingensis, a member of the Sciaenidae (the drums or croakers), and an example of a fecund and commercially important group of fishes that appears to be especially vulnerable to fishing. We also demonstrate that the careful use of informal, or traditional, information can provide a powerful, sometimes unique, means of identifying and assessing the status and history of species that might be quietly slipping away before we learn anything about them.  相似文献   
5.
The guava processing industry in Malaysia produces by-products in the form of seed core and peel. These by-products can be regarded as underused resources but there are concerns about their composition that prevent their use in the food and feed industries. This study aims to analyze the respective effects of heat treatments (boiling or autoclaving) and germination periods on the nutritional composition and phytochemical content of guava seeds. The guava seeds were found to contain 618, 78, 72, and 5 mg/g dry weight total dietary fiber, fat, protein, and ash, respectively. The tannin and saponin contents, but not the phytic acid content, were below the respective anti-nutritional thresholds. The heat treatments did not affect the total dietary fiber and ash contents but reduced all other chemical components to different extents (15–91 %). Boiling did not reduce the phytic acid content substantially but autoclaving caused a reduction of 91 % to a level below the anti-nutritional threshold. Germination for 14 days caused a significant reduction in nutrient contents in the range of 16–79 %. Germination also reduced the phytic acid content by 90 % in the seed but did not significantly affect the saponin content. Thus, guava seed can be treated thermally or germinated to manipulate its chemical composition to enable its use in the food and feed industries.  相似文献   
6.
探讨了选用芒果落果、疏果为原料,加工芒果腌菜的工艺技术。利用芒果落果和疏果加工制作腌菜具有原料廉价、质地佳、风味突出、工艺简单等特点,便于在芒果产区普及与推广。  相似文献   
7.
Chiu PY  Lam PY  Yan CW  Ko KM 《Fitoterapia》2011,82(4):682-691
The effects of schisandrin B (Sch B) and its analogs on solar irradiation-induced oxidative injury were examined in BJ human fibroblasts. Sch B and schisandrin C (Sch C) increased cellular reduced glutathione (GSH) level and protected against solar irradiation-induced oxidative injury. The photoprotection was paralleled by decreases in the elastases-type protease activity and matrix-metalloproteinases-1 expression in solar-irradiated fibroblasts. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production. The results suggest that by virtue of its pro-oxidant action and the subsequent glutathione antioxidant response, Sch B or Sch C may offer the prospect of preventing skin photo-aging.  相似文献   
8.
Gas chromatography was used to quantitate free galactose in Braeburn, Fuji, Red Delicious, and Spartan apples during cold storage, after thermal processing of apple slices and in juice produced using clarification and/or liquifaction enzymes. Spartan had significantly higher galactose levels as compared to Red Delicious apples, but changes in galactose in all varieties during 9 months of cold storage were insignificant. Blanching and canning decreased galactose levels, but doubling the thermal processing during canning increased the free galactose concentration detected in plant tissue. An enzymatic liquefaction aid used to prepare apple juice dramatically increased the free galactose content while a clarification aid caused only a slight increase due to its selective action on soluble pectin. These findings provide useful information for dietitians to base diet recommendations for galactosemic patients.  相似文献   
9.
The almond major storage protein, amandin, was prepared by column chromatography (amandin-1), cryoprecipitation (amandin-2), and isoelectric precipitation (amandin-3) methods. Amandin is a legumin type protein characterized by a sedimentation value of 14S. Amandin is composed of two major types of polypeptides with estimated molecular weights of 42-46 and 20-22 kDa linked via disulfide bonds. Several additional minor polypeptides were also present in amandin. Amandin is a storage protein with an estimated molecular weight of 427,300 +/- 47,600 Da (n = 7) and a Stokes radius of 65.88 +/- 3.21 A (n = 7). Amandin is not a glycoprotein. Amandin-1, amandin-2, and amandin-3 are antigenically related and have similar biochemical properties. Amandin-3 is more negatively charged than either amandin-1 or amandin-2. Methionine is the first essential limiting amino acid in amandin followed by lysine and threonine.  相似文献   
10.
为实现袋鼠临床样本中疱疹病毒1型(Macropodid herpesvirus 1,MaHV-1)的出入境快速检测,基于MaHV-1的gB基因序列设计特异引物和TaqMan探针,建立了一种MaHV-1荧光PCR检测方法。试验结果显示,该方法只对MaHV-1 gB基因呈现特异性扩增,与禽传染性喉气管炎病毒、伪狂犬病毒和牛传染性鼻气管炎病毒不发生交叉反应,对阳性标准质粒对照(pCR-MaHV-1-gB)的最低检测限为8个拷贝数/反应。该方法的组内和组间试验的Ct值变异系数介于0.17%~0.96%之间,具有良好的重现性。试验结果表明,本研究建立的实时荧光PCR方法可用于袋鼠MaHV-1的病原学检测。  相似文献   
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