居室放射性及其对策

介绍了居室放射性的概念，度量单位，危害，影响因素及其分布特点，提出了防护对策。     

Determination of Carcinogenic Heterocyclic Amines in Satay by Liquid Chromatography

The successful determination of mutagenic/carcinogenic heterocyclic amines (HCAs) in trace amounts (ng/g, ppb levels) in commercial foods depends largely on the detection sensitivity and selectivity, as well as the quality of clean-up of complex food matrices. In the present study, UV and fluorescence detection in series with gradient elution HPLC was used for the separation and determination of eight HCAs present in a local delicacy, satay. The identification of peaks was carried out by UV diode-array spectrophotometry. The most common HCA found in all types of satay (chicken, mutton, pork) cooked under Chinese and Malay styles was 2-amino-9H-pyrido[2,3-b]indole (AC) (1.3-12 ppb) while 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) was found at comparatively high levels (78 ppb) in both Chinese-style pork and Malay-style chicken satay. Other major HCAs included 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) (non-detectable (ND) to 31 ppb), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) (ND-12 ppb) and 2-aminodipyrido[1,2-a:3,2-d]-imidazole (Glu-P-2) (ND-25 ppb). Comutagen norharman (NH) was also detected at levels up to 84 ppb, while harman (H) was only detected in one sample (Chinese-style pork satay), at a level of 25 ppb. The differences in the type and level of HCAs in satay samples may be attributed to the variation in raw foodstuffs cooked under different styles by Chinese or Malay vendors, and the ingredients added during cooking.     

The amplification refractory mutation system (ARMS): A rapid and direct prenatal diagnostic technique for β-thalassaemia in Singapore

β-Thalassaemia major patients have chronic anaemia and since 3–4 per cent of Singaporeans carry the β-gene, prenatal diagnosis is essential. We evaluated the amplification refractory mutation system (ARMS) technique as a routine test for prenatal diagnosis of β-major. Six mutations along the β-gene were studied—41–42 (-TCTT), IVSII #654 (C-T), 17β (A-T), – 28 TATA (A-G), IVSI #5 (G-C), and IVSI #1 (G-T). Our results indicate that prenatal diagnosis using these mutations can be offered to 90 per cent (35/39) of our Chinese couples and 54·6 per cent (12/22) of our Malay couples at risk. Confirmation of ARMS results was carried out using allele-specific oligonucleotide hybridization. Prenatal diagnosis using ARMS was successfully carried out in nine cases which included a set of triplets and twins. The triplets were diagnosed with the β-trait carrying the 41–42 mutation. The couple with twins possessed the #654 mutation and one twin was diagnosed with the β-trait and the other with #654 homozygosity. Genomic sequencing of the undefined mutations in the Chinese couples revealed rarer mutations at − 29 and an ATG-AGG base substitution at the initiation codon for translation. In the Malay couples, genomic sequencing detected mutations at codon 15 (TGG-TAG) and codon 26 (GAG-AAG). We conclude that ARMS with its direct detection of amplified products by gel electrophoresis provides an accurate, rapid, and simpler method for our β-thalassaemia prenatal diagnosis programme in Singapore.     

Aluminium and fluoride concentrations of three tea varieties growing at Lantau Island,Hong Kong

The present project aims to investigate aluminium (Al) and fluoride (F) contents in teas (Camellia sinensis (L.) O. Kuntze). Three different commercial tea varieties: Assam variety and two China sub-varieties, a large leafed variety and small leafed variety, were collected in two tea gardens of Lantau Island tea plantation of Hong Kong. In general, high concentrations of Al and F were accumulated in the mature leaves (15.3 and of 2.07 g kg^–1 respectively). Among the three varieties, the small leafed variety exhibited the highest Al and F contents followed by the large leafed variety whereas the Assam variety had the lowest Al and F concentrations in its tea bushes. Tea products from a plantation were also analysed and it was noted that black tea had higher Al and F concentrations than green tea. The amount of Al and F released into tea liquor was also tested and the results showed that higher concentrations of Al and F were released into tea liquor under repeated infusion method than continuous infusion method.     

综合地震台网络办公自动化系统

计算机与网络技术高速发展的今天，办公自动化（OA）系统现已在各行各业得到广泛应用。目前市场上的办公软件产品很多且功能强大，但由于各个行业本身的特殊性，这些系统很不适合应用于地震部门。本文研究了综合地震台如何搭建适合自己的经济、简单、实用的OA系统，为国内其他地震台实现OA作一些建设性的理论及技术参考。     

东南亚沿海生态旅游的趋势

当地居民的生活需求、保护生物多样性的必要性和娱乐旅游使得东南亚海岸资源压力不断增 加 .在这种情况下 , 沿海生态旅游会扮演越来越重要的角色 .这篇文章考察了泰国、菲律宾、 印度尼西亚、马来西亚和越南的沿海生态旅游的开发 .     

Effects of anoxia on the activities of pyruvate kinase and phosphoenolpyruvate carboxykinase,and the production of lactate and succinate in the intertidal pulmonate Onchidium tumidium

Onchidium tumidium, an intertidal pulmonate, has evolved to depend mainly on the formation of succinate, rather than lactate and opines, to survive in anoxia. For our study O. tumidum were collected from the mud flats of the mangrove swamp at Mandai, Singapore between 1988 and 1991. After 24 h of anoxic exposure, the lactate and succinate contents of the anoxic individuals were approximately 10 and 150 times, respectively, the corresponding values of the normoxic individuals. Alanine and acetate accumulations also occurred during anoxia, though to a much lesser extent. No propionate or octopine was detected. The depletion in aspartate content in O. tumidium could not account for the amount of succinate accumulated during anoxia. The succinate formed might have originated from glycogen involving the flow of carbon through the phosphoenolpyruvate (PEP) branch point of glycolysis. In support of such a hypothesis, results indicate that there was a decrease in the affinity of pyruvate kinase from O. tumidium exposed to 24h of anoxia to PEP to facilitate succinate formation through phosphoenolpyruvate carboxykinase (PEPCK). In comparison, the affinity of PEPCK from O. tumidium exposed to anoxia to PEP was apparently unaltered.     

渗滤湿地系统的工艺设计

本研究是以占地6公顷,日处理污水1400m~3的渗滤型芦苇湿地实验工程为依托,采用静态模拟与工程运转相结合的方法,着重对污水湿地处理系统BOD_5的生物降解模型进行研究,建立了确定Q值和K_T值的方法,提出了适于天津渗滤湿地系统的Q值和K_T值,为湿地系统设计提供了重要的科学依据.     

A novel respirometer for biological toxicity tests

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长江,嘉陵江重庆段水污染控制规划

根据水质预测结果用组合规划的方法对长江，嘉陵江重庆干流段和城区段的水污染控制提出了多个不同的方案，并对各方案进行了比较，从水质，经费和施工的可行性３个方面综合评定，筛选出优先考虑方案，同时对方案实施后的效益作出了简要的叙述。