小鼠10号染色体上致聋突变基因hml的精确定位(英文)

目的　定位小鼠致聋基因 ,识别决定其性状的有关突变 ,为人类耳聋基因研究提供动物模型。方法　利用全基因组扫描来定位名为hml可致小鼠听力丧失突变基因。结果　①hml基因定位在小鼠 10号染色体上 ,距中心粒约4 3cM处。根据已知的鼠 人同源同线性特点 ,提示人的同源基因位于 12 q2 2 -q2 4 ;②获得了 2 5个多态性微卫星标记 ,通过高分辨的小鼠图谱将 3个已知人类基因进行了正确排列 ,并将hml侯选基因限定在一个 5 0 0kb的区域内。     

Book reviews

THE U.S. AIRFREIGHT INDUSTRY, by Nawal K. Taneja. Lexington Books, Lexington, Mass., 1979. 244 pp.

TRAFFIC, OPERATIONAL RESEARCH, FUTUROLOGY, by Arne Jensen. North Holland Publishing Company, Amsterdam, 1980. 321 pp. ($39.00)

PROBLEMS OF THE CARLESS, by R. E. Paaswell and W. W. Recker. Praeger Publishers, New York, 1978. 190 pp.

TRANSPORTATION AND THE ELDERLY, by Martin Wachs. University of California Press, Berkeley, 1980.

PUBLIC TRANSPORTATION: PLANNING, OPERATIONS AND MANAGEMENT, edited by George E. Gray and Lester A Hoel. Prentice Hall, Englewood Cliffs, New Jersey, 1979. 749 pp.

ETHYL ALCOHOL PRODUCTION AND USE AS A MOTOR FUEL, edited by J. K. Paul. Noyes Data Corporation, New Jersy, 1979. 354 pp ($48.00).

URBAN PLANNING AND PUBLIC TRANSPORT, edited by Roy Cresswell. The Construction Press, London, 1980. 172 pp. (£15.00)     

Benefit transfers: are they a satisfactory input to benefit cost analysis? An airport noise nuisance case study

Benefit cost analysis in a variety of guises has established itself as a useful tool in public policy-making. It is an approach widely adopted in appraising a wide range of infrastructure investments and has been regularly used in legal proceedings. In the context of this study, it forms a common procedure for assisting in the assessment of the social benefits and costs of airport investment. It is not, however, a technique without its limitations. Beside a range of technical concerns, conducting a comprehensive benefit cost analysis can be resource-intensive and time-consuming. Recently, there have been efforts to make its application more efficient by adopting benefit transfer procedures. This involves making use of findings from one study as inputs into other policy-making activities. While applying secondary data to a new policy issue has a long pedigree, new areas of application involve taking non-market valuations of externalities from one study and transferring them to a different policy site. This paper looks at some of the limitations of employing benefit transfers and uses noise nuisance aspect of airport investment policy appraisal as an illustrative case. Based upon a meta-regression assessment of hedonic price models, the findings suggest that caution should be exercised in conduction benefit transfers.     

Short-line railroad managers discuss their industry

In the United States, the 1980 Staggers Rail Act created a positive regulatory environment for the creation of new short-line railroads. At present there are about 450 of these railroads that have less than 250 miles of trackage. This study asked managers/owners of these railroads two basic questions. First, what do you believe is the single most important trend that is currently taking place in your industry. The most frequently noted trend was the frustration of working with the larger Class 1 railroads. Five additional trends were also identified by the respondents. The second question asked the respondents if they thought the short-line sector of the rail industry will become more or less important in the next ten years and why. About 70% of the owner/managers believed their industry would become more important in the next decade. The most commonly expressed reason for this position is that the Class 1 railroads will increasingly specialize in mainline service only. Three other rationales were also enumerated. For the managers that thought their industry would become less important, the most noted reason was their trackage would not safely transport the newer very heavy bulk commodity freight cars.     

A summary of the formation and seasonal progression of the Northeast Water Polynya

A summary of the seasonal development of the Northeast Water Polynya ice cover characteristics is presented. This is based primarily on satellite remote sensing observations, with some in situ measurements, including both new and published data.     

Winter intensification and water mass evolution from yearlong current meters in the Northeast Water Polynya

In the summer of 1992, four current meter moorings were deployed in and later retrieved from the Northeast Water (NEW) polynya on the East Greenland Shelf by the USCGC Polar Sea. The moorings provided hourly temperature, salinity and current data for approximately one year. In the NEW, the circulation intensified and steadiness increased during winter. This intensification was most readily observed at 150 m on the southern side of Westwind trough. The surface layer freshened from summer through December due to ice-melt and freshwater runoff mixing down to at least 75 m. From December through early spring, salinity increased probably due to brine rejected during ice formation. Wintertime events showed water at 75 m with temperatures at the freezing point. Knee Water (KW) was not observed in the current meter data. However, a warmer and fresher than KW watermass was observed at 150 m over the shelf and may result from mixing outside the NEW among KW and the major water masses influencing the region. Polar Water and Atlantic Intermediate Water. Several short-lived events of 3 to 7 days duration perturbed the T-S character at each of the current meters. We believe that these T-S shifts were anticyclonic eddies advecting through the NEW polynya. During such perturbations, T-S values found generally at 75 m were observed at 150 m and T-S values generally at 150 m were observed at 250 m. On the northern side of the Westwind trough, the current meter data provided direct evidence for westward flow into the western extent of the trough at a depth of 250 m. This southwesterly current along the northwest slope of the trough at 250 m is in agreement with the summertime ADCP measurements made in 1992 aboard Polar Sea, and is consistent with the flow inferred from summer hydrography measured from Polarstern in 1993.     

Methods of analysis for vehicle soak time data

Vehicle soak time, the duration of time a vehicle’s engine is at rest prior to being started, and its distribution function are important transportation activity data inputs for mobile emissions inventory estimation due to their impacts on vehicle start and evaporative emissions. This paper provides vehicle emission researchers with an overview of statistical analysis methods relevant to analyzing vehicle soak time data. Many of these methods are already in use in emissions research and have appeared in the literature. These methods are reviewed and further details regarding the implementation and interpretation of these methods are provided. Statistical methods relevant to the analysis of soak time data that have yet to appear in the emissions literature, including kernel density estimation and generalized linear models, are also introduced. Advantages and disadvantages of the methods are compared and theoretical justification is provided. Issues of correlated observations and censored data are discussed. General guidelines for the analysis of soak time data, such as stratification by start type and geographical region, are established. Finally, a subset of the statistical methods discussed is used to analyze the US Environmental Protection Agency’s 3-city data.     

Constraint Mapping as a Means of Further Refining Saltmarsh Re-Creation Opportunities for the UK Solent Region

Based on geomorphological criteria, the Coastal Habitat Management Plan (CHaMP) for the Solent identified some 4,800 hectares of land potentially suitable for the creation of intertidal habitat, principally saltmarsh, through the use of managed realignment. Using “constraint mapping,” this study set out to illustrate that limitations to habitat re-creation through inundation are not merely geomorphological in nature. Indeed, a broad range of social, political, legal, technical, and economic constraints exist and must be evaluated in conjunction with physical parameters if the objectives of the European Birds and Habitats Directives are to be met, and so that future coastal defense policies ensure maintenance of the “favorable conservation status” of designated sites. A numerical filter system has been used to re-evaluate individual sites to establish “realistic” opportunities for compensatory saltmarsh creation in the Solent. As a result of taking into account wider socioeconomic constraints, it is clear that fewer areas are available for habitat creation purposes than were initially identified in the Solent CHaMP study.