北京PM₁₀的生物活性与微量元素的相关性研究   总被引：1，自引：0，他引：1  

吕森林  邵龙义  吴明红  T.Jones  L.Merolla  R.J.Richard 《中国科学D辑》2006,36(8):777-784

在使用质粒DNA评价法对北京PM₁₀的生物活性进行研究的基础上, 结合PM₁₀中微量元素分析结果, 探讨了PM₁₀对质粒DNA产生损伤的原因. 研究表明北京不同季节、不同地区PM₁₀对DNA的氧化性损伤有明显的差别. 冬季市区和对照点PM₁₀(全样)的TM50分别是900和74 μg·mL^-1, 水溶组分的TM50分别是540和86 μg·mL^-1; 夏季市区和对照点PM₁₀(全样)的TM50分别是116和210 μg·mL^-1, 水溶组分的TM50分别是180和306 μg·mL^-1; 北京PM₁₀的生物活性的差别主要来自PM₁₀中微量元素含量的不同. PM₁₀(全样)中Pb, Zn和As三种元素对质粒DNA氧化性损伤能力较强; 而PM₁₀水溶组分中Mn, V, Zn同TM50的相关性较高; Zn元素可能是导致PM10具有氧化性损伤能力的主要微量重金属元素.  相似文献   

Quantifying climatic change through the last glacial–interglacial transition based on lake isotope palaeohydrology from central Turkey     

Matthew D. Jones  C. Neil Roberts  Melanie J. Leng   《Quaternary Research》2007,67(3):463-473

Questions remain as to the nature of climatic change through the last glacial–interglacial transition in the eastern Mediterranean region, particularly the relative contribution of evaporation and precipitation to regional water balance. Here changes in oxygen isotope values through this time period from Eski Acıgöl, a crater lake in central Turkey, are investigated using hydrological and isotope mass balance models. These allow changes in evaporation and precipitation to be quantified and their relative importance evaluated. We show that it is the volumetric flux rate of water passing through the lake system and not the precipitation-to-evaporation ratio per se which controlled the stable isotope record in Eski Acıgöl. Early Holocene precipitation is shown to be much greater than that during both the latter part of the last glaciation and the present day. We test these calculated values against other records in the same region, firstly with other lake records in Anatolia, the Konya basin and Lake Van, and secondly with isotope-inferred palaeo-precipitation data from Soreq cave in Israel. This reveals a contrast between pre- and post-LGM precipitation values in Turkey (wetter and drier, respectively) and also suggests that during the last glacial–interglacial transition there was a more marked precipitation gradient than at present between northern/interior and southern/coastal parts of the eastern Mediterranean region.  相似文献   

Getting it wrong first time: building an interdisciplinary research relationship   总被引：1，自引：0，他引：1  

Phil Jones  Neil Macdonald 《Area》2007,39(4):490-498

This paper addresses recent debates on the need for greater collaboration across the physical and human geography divide. We discuss some of the problems of producing work that can be considered genuinely interdisciplinary. The paper reflects on a project examining the use of sustainable drainage systems in Glasgow and how we unwittingly produced a piece of social science research looking at a physical science topic. We suggest that more than simply the need for 'trust' between researchers, the actual practice of working together in the field – and, indeed, having the opportunity to make mistakes and learn from them – is essential. In working together, academics have a better opportunity to understand each other's intellectual and epistemological framework and develop projects where researchers can move beyond their disciplinary boundaries and weave their expertise into a coherent research output.  相似文献   

Features of faults in the central and northern Tibetan plateau based on results of INDEPTH (III)-MT     

Wei Wenbo  Jin Sheng  Ye Gaofeng  Deng Ming  Tan Handong  Martyn Unsworth  John Booker  Alan G. Jones  Li Shenghui 《Frontiers of Earth Science》2007,1(1):121-128

The features of the faults in the central and northern Tibetan plateau are discussed, based on two super-wide band magnetotelluric (MT) sounding profiles belonging to the INDEPTH (III)-MT project, which were finished between 1998 and 1999: one is from Deqing to Longweicuo (named line 500), the other is from Naqu to Golmud (line 600). This work assists research on the collision and subduction mode between the India and Asia plates. The MT results show that there is a series of deep faults, F1 to F10, in the central and northern Tibetan plateau. Of these faults, F2 is an earlier main fault which leans to the north, and F1 is a later main overriding fault. The Jiali deep fault zone, which has a very complex space structure, is composed of these two faults. F3, F4 and F5 are super-deep faults. They are high-angle faults and lean a little to the south. The main fault zone of the Bangong-Nujiang suture is composed of these three faults. Because of later activity in the structure, several shallow faults formed in the upper crust within the Bangong-Nujiang suture. The Tanggula fault zone is composed of two main faults, F6 and F7, and a series of sub-faults. The shallow segments of the main faults are in high angles and the deep segments of main faults are in low angles. These two faults generally lean to the south and extend into the lower crust. The Jinshajiang suture is composed of the Jinshajiang fault (F8) and the Kekexili fault (F9), and there is a series of sub-faults in the upper crust between these two faults. The Jinshajiang suture is a very wide suture caused by continent-continent collision. The Middle Kunlun fault (F10), which is the main structure of the Kunlun fault zone, is a high angle, super-deep fault. It is the north boundary of the Songpan-Ganzi-Kekexili block. Based on the conductive structure of the profile, the southern part of the Middle Kunlun fault belongs to the Tibetan plateau, but it is not certain whether the northern part of the Middle Kunlun fault belongs to the Tibetan plateau. There are conductive bodies stretching from the crust into the upper mantle below the Bangong-Nujiang suture and Jinshajiang suture. This may suggest heat exchange between the crust and mantle. Translated from Earth Science—Journal of China University of Geosciences, 2006, 31(2): 257–265 [译自: 地球科学—中国地质大学学报]  相似文献   

Editor's note     

Thomas A. Jones 《Mathematical Geology》1985,17(2):215-217

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A technique for computing geoid height anomalies over two-dimensional earth models     

Glyn M. Jones 《Geophysical Journal International》1982,69(2):329-337

Summary A technique is presented for calculating geoid height anomalies over two-dimensional models of Earth structure. The method consists of convolving gravity anomalies over the structure with filters which take into account the finite size of the structure in the third dimension and the curvature of the Earth. Similar filters are also developed for a flat earth case. The method is applied to a sea-surface gravity profile crossing the Tonga-Kermadec trench and is found to give good agreement with a Geos-3 radar altimetry profile in the same region. The example demonstrates that introducing arbitrary offsets in computing gravity anomalies can result in spurious long-wavelength effects in the computed geoid. Comparison of the results obtained using flat earth and spherical earth filters suggests that the effects of the curvature of the Earth only become significant for wavelengths in the gravity field greater than about 1000 km.  相似文献   

A reinterpretation of the precursory seismic b-value anomaly from fracture mechanics   总被引：1，自引：0，他引：1  

Ian G. Main  Philip G. Meredith  Colin Jones 《Geophysical Journal International》1989,96(1):131-138

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Book reviews     

L. D. Wright  Harry H. Roberts  Arnold H. Bouma  Harold W. Borns Jr.  A. B. Carpenter  R. W. Jones  J. R. Wood 《Geo-Marine Letters》1986,6(1):57-61

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Oxygen and carbon stable isotopes in otoliths record spatial isolation of Patagonian toothfish (Dissostichus eleginoides)     

Julian Ashford  Cynthia Jones 《Geochimica et cosmochimica acta》2007,71(1):87-94

Strong contrasts in ambient isotope ratios and in diet suggest stable isotopes in the otoliths of oceanic fish can resolve water masses and geographic areas, promising a powerful multivariate approach for examining population structure and provenance. To test this, whole otoliths were taken from Patagonian toothfish (Dissostichus eleginoides) sampled off the Patagonian Shelf and South Georgia, on either side of a population boundary, and otolith δ¹⁸O and δ¹³C values were measured to see if they could distinguish South American-caught fish from those taken in the Antarctic. Values of otolith δ¹⁸O and δ¹³C predicted capture area with 100% success, validating their use for distinguishing provenance and corroborating the prior evidence of population isolation. Values of δ¹⁸O in the otoliths reflected ambient values as well as seawater temperature: low values in Patagonian Shelf fish were consistent with exposure to Antarctic Intermediate Water (AAIW), and high values in South Georgia fish were consistent with exposure to Circumpolar Deep Water (CDW). In contrast, differences in otolith δ¹³C appeared to reflect diet: relative depletion of otolith δ¹³C at South Georgia compared to the Patagonian Shelf were most likely linked to differences in sources of metabolic carbon, as well as δ¹³C in dissolved inorganic carbon (DIC) of seawater. These contrasting properties strongly suggest that stable isotopes can resolve the provenance of toothfish from Antarctic sampling areas that hitherto have been difficult to separate. These results show that, by using the chemistry recorded in otoliths, researchers can exploit biogeochemical variation in fully marine environments to examine the spatial ecology of oceanic fish.  相似文献   

Transient simulations,empirical reconstructions and forcing mechanisms for the Mid-holocene hydrological climate in southern Patagonia     

Sebastian Wagner  Martin Widmann  Julie Jones  Torsten Haberzettl  Andreas Lücke  Christoph Mayr  Christian Ohlendorf  Frank Schäbitz  Bernd Zolitschka 《Climate Dynamics》2007,29(4):333-355

This study investigates the atmospheric circulation in transient climate simulations with a coupled atmosphere–ocean general circulation model (GCM) for the mid-Holocene (MH) period 7–4.5 ka BP driven with combinations of orbital, solar and greenhouse gas forcings. The focus is on southern South America. Statistical downscaling models are derived from observational data and applied to the simulations to estimate precipitation in south-eastern Patagonia during the MH. These estimates are compared with lake level estimates for Laguna Potrok Aike (LPA) from sediments. Relative to pre-industrial conditions (i.e. 1550–1850), which show extraordinarily high lake levels, the proxy-based reconstructed lake levels during the MH are lower. The downscaled simulated circulation differences indicate higher LPA precipitation during the MH from March to August, higher annual means, and reduced precipitation from September to February. Thus the reconstructed lower LPA lake levels can not be explained solely by the simulated precipitation changes. Possible reasons for this discrepancy are discussed. Based on proxy data from southern South America hypotheses have also been proposed on the latitudinal position of the southern hemispheric westerlies (SHWs). In agreement with some of these hypotheses our simulations show an increased seasonal cycle of the latitudinal position of the SHWs during the MH, which can be explained by the orbital forcing. The simulations also show stronger SHWs over southern Patagonia during austral summer and weaker SHWs during winter. The downscaling model associates weaker SHWs with increased precipitation in the LPA region. However, this relationship is only moderate, and therefore the downscaling model does not support the assumption of a strong link between mean SHWs and precipitation over south-eastern Patagonia, which is the basis of many proxy-based hypotheses about the SHWs.  相似文献