Assessment of Committed Effective Dose due to consumption of Red Sea coral reef fishes collected from the local market (Sudan)

An assessment of Committed Effective Dose (CED) due to consumption of Red Sea fish containing (210)Po and (137)Cs was performed for 23 different marine fish samples collected from the local market at Port Sudan. The fish were classified according to their feeding habits into three categories: carnivores, herbivores, and omnivores. Measured activity concentrations of (210)Po were found in the ranges 0.25-6.42 (carnivores), 0.7-5 (omnivores) and 1.5-3.8 (herbivores) Bq/kg fresh weight. In the same study, activity concentrations of Cs-137 were determined to be in the ranges 0.1-0.46 (carnivores), 0.09-0.35 (omnivores) and 0.09-0.32 (herbivores) Bq/kg fresh weight, which were several times lower than those of (210)Po. Appropriate conversion factors were used to derive the CED, which was found to be 0.012, 0.01 and 0.01 (microSv/yr) in carnivores, omnivores and herbivores, respectively, for (137)Cs. This contributes about 0.4% of the total dose exclusively by ingestion of fish. For (210)Po, it was found to be 3.47, 4.81 and 4.14 (microSv/yr) in carnivores, omnivores and herbivores, respectively, which represents 99.6% of the total dose (exclusively by ingestion of fish). The results of CED calculations suggest that the dose received by the Sudanese population from the consumption of marine fish is rather small and that the contribution of (137)Cs is negligible compared to (210)Po.     

Detection of a pathway from linoleate to a novel cyclopentenone: cis-12-oxo-10-phytoenoic acid in sunflower roots

The lipoxygenase pathway in sunflower roots was studied in vitro. A preliminary incubation of linoleic acid with 15 000 g supernatant of homogenate of sunflower roots (1.5-6 days after germination) revealed the predominant activity of 13-lipoxygenase. The exogenously added linoleic acid 13-hydroperoxide is further utilized through two competing pathways. One of them is directed towards formation of the ketodiene (9Z,11E)-13-oxooctadeca-9,11-dienoic acid. The second pathway, which is controlled by allene oxide synthase, leads to the formation of an alpha-ketol and a novel cyclopentenone, rac-cis-12-oxo-10-phytoenoic acid (12-oxo-PEA) via a short-lived allene oxide. Unexpectedly, the cyclopentenone 12-oxo-PEA is the predominant allene oxide synthase product. Identification of cis-12-oxo-PEA was confirmed by its UV, mass, (1)H NMR and 2D-COSY spectral data. The highest yield of 12-oxo-PEA is observed in very young roots (1.5-2 days after germination). The results of methanol-trapping experiments demonstrate that both 12-oxo-PEA and alpha-ketol are formed through the unstable allene oxide intermediate, (9Z)-12,13-epoxyoctadeca-9,11-dienoic acid, which is the primary product of allene oxide synthase. Since 12-oxo-PEA is a jasmonate congener, its biosynthesis in plants might be of physiological importance.     

Promoting medical knowledge regarding nutrition in the modern era

The paper presents the analysis based on the data available in the literature on the problem of sanitary-and-hygienic education in the general population concerning proper diet which is generally considered to be a major aspect in prevention of noninfectious diseases. Differential approach in presenting information on diet for different groups of people, and in observing definite guidelines while planning educational measures is thought to be rather significant. The paper presents the ways for more effective promotion of sanitary-educational measures in dietary habits and more rational activities of health services in planning and realizing the popularization of proper diet.     

多维减振阻尼器力学性能研究

大跨空间结构由于结构布局的多维性和所受荷载的多维性,其结构响应具有明显的多维特征。对于单层网格形式的大跨空间结构,其结构构件通常受“弯矩-轴力”多维内力组合作用,与桁架形式的大跨空间结构中仅受轴力的杆件有很大区别。为此提出了一种适用于大跨空间结构的多维减振阻尼器,其具有同时提供轴向、弯曲等多维刚度和减振效果的特征。针对该阻尼器力学性能进行分析,推导了阻尼器的多维刚度公式。采用MATLAB编制程序求解理论公式,并与ABAQUS仿真结果进行了对比。对其静力性能进行验证,并探讨了多维减振阻尼器的动力耗能能力以及在大跨空间结构中的减振效果。研究结果表明：多维减振阻尼器在受静力作用时具有轴向、弯曲等多维刚度,从而减少因替换杆件对结构造成的削弱;在动力荷载作用下,耗能性能良好,可以为大跨空间结构提供有效多维减振;采用多维减振阻尼器替换杆件后,结构节点的竖向位移峰值降幅达43.3%,竖向加速度峰值降幅47.1%。     

Inter-individual differences in the ability of human milk-fat extracts to enhance the genotoxic potential of the procarcinogen benzo[a]pyrene in MCF-7 breast cells

Environmental factors are believed to play an important role in cancer aetiology. Whether environmental pollutants act in isolation or in combination within mixtures remains unclear. Four human milk-fat extracts (from resident U.K. women) were screened for levels of organochlorinated and brominated compounds prior to being tested (1-50 mg-equiv) for micronucleus (MN)-forming activity in MCF-7 cells. Using the cytokinesis-block micronucleus assay, micronuclei (MNi) were scored in 1000 binucleate cells per treatment. Cell viability (% plating efficiency) and immunohistochemical detection of p53 induction were also measured. The effects of treatment with 1 mg-equiv of extract in combination with benzo[a]pyrene (BP) were also examined. BP-DNA adducts were detected and quantified by 32P-postlabeling analysis. Dose-related increases in MNi independent of pollutant concentrations were induced by milk-fat extracts. All four extracts elevated the percentage of p53 positive cells, although not always in a dose-related fashion. Some combinations resulted in profound low-dose-induced increases in MNi and significant elevations in the percentage of p53 positive cells, which occurred without further reduction in cell viability or mitotic rate. When one particular extract was combined with BP, a 100-fold increase in BP-DNA adducts was detected as compared with the levels induced by BP alone; an effect not induced by other extracts. This adduct-enhancing extract was fractionated into 14 fractions that were subsequently tested (1 mg-equiv of original extract) in combination with 0.01 microM BP. Fraction 1, into which nonpolar pollutants mostly eluted, enhanced MN-forming activity with BP. Surprisingly, the more polar and less likely to contain fat-soluble pollutants fractions 5 and 8 also enhanced MN-forming activity. No identifiable pollutants were present in these fractions. The results suggest that different environmental pollutants present in human tissue may influence the susceptibility of target cells to initiating events.     

非一般的亚青 非一般的巡演——亚青巡演随笔散记（下）

亚州青年管弦乐团除了在香港这个“基地”登台,今年在五个城市七个场馆的巡演（7月31日至8月20日）,除了最后一站在台北国家音乐厅的两场演出未能分身,其余六个场馆,以第四站在东京的首场演出（10日）所在的墨田三声音乐厅（Sumida Triphony Hall）,让人印象最为深刻。这并非是说英国著名指挥朱特（James Judd）,星级小提琴大师奥利维拉（E．Oliveria独奏“柴协”）     

印度软件产业的崛起对我国的启示

随着世界科技浪潮的蓬勃兴起,一个以推广应用计算机技术为基础的人工信息智能技术———软件产业,在科技领域得到迅猛发展。现在,软件产业规模和水平已经成为一个国家现代化程度和综合国力的重要标志之一。随着我国国民经济信息化的迅猛发展,计算机软件已渗透到国民经...     

化妆美容病与化妆品

化妆美容病与化妆品孟凡夫（大连１１６０１５）随着人民物质文化水平的不断提高，美的意识日益增高，对化妆品的需求也越来越高。在当前的化妆品市场上，美容护肤、营养、抗衰老、防皱、增白、防晒、消斑、生发以及各种药物性化妆品琳琅满目，日趋繁荣，不断丰富和满足人...     

总队紧急部署夏季消防安全工作 要求确保全年火灾形势总体稳定

7月2日，正在建设的北京大学体育馆（奥运乒乓球馆）发生火灾，中央领导同志和公安部领导高度重视，周永康、陈至立、刘金国等领导分别做出了重要批示。7月4日，湖南衡阳一电影院又发生一至五楼近6000平方米过火、影响较大的火灾事故。     

Resonance ionization image detectors: basic characteristics and potential applications

A type of spectrally selective imaging optical detector that is based on resonance ionization in an atomic vapor is proposed. It has the potential for improved spatial, spectral, and temporal resolutions compared with those of available techniques. Figures of merit are calculated and compared with those of existing techniques. Several potential applications such as the imaging of moving objects, ultrasonic fields, high-energy particle detection, and optical communications are discussed.