The medical geology revolution

Because of the importance of geological factors on health an International Working Group on Medical Geology was established in 1998, with the primary aim of increasing awareness of this issue among scientists, medical specialists, and the general public. In 2000 a new project was established by UNESCO. The primary aim of the projects was to bring together, on a global scale, scientists working in this field in developing countries with their colleagues in other parts of the world. The International Council of Scientific Unions （ICSU） also sponsored international short courses in this subject, a cooperation involving The Geological Survey of Sweden, US Geological Survey and the US Armed Forces of Pathology. In 2006 a new association was established： International Medical Geology Association, IMGA. Regional Divisions all over the world have been established. Two text books have been published, the most recent one by Elsevier 2005： Essentials of Medical Geology which has received two prestigious international awards. A website （ http：//www.medicalgeology.org ） and regular newsletters have been published. Short courses on medical geology, have been held since 2001 in more than 30 countries. Medical geology will also be one of the ten main topics within the Year of Planet Earth declared by UN General Assembly December 22, 2005. Medical geology is also one of the five topics within the GeoUnion initiative. The international impact has been tremendous. Universities all around the world are starting courses and education in medical geology, the first centers are under construction, symposias have been held and a world wide collaboration has started between geoscientists, environmental researchers, epidemiologists, toxicologists, pathologists and other scientists.     

Determining depleted uranium （DU） contamination in soils and salt marsh sediments in the vicinity of DU munitions testing sites in SW Scotland and NW England, UK

In its natural state uranium has three isotopes; ^238U （99.27 atom % abundance）, ^235U （0.72%） and ^234U （0.0055%）, with the ^235U ： ^238U activity ratio having a constant value of 0.045 and the ^234U：^238U activity ratio commonly ranging 0.8-1.2 for soils and sediments （e.g. Fisenne 1996）. Uranium enrichment, the process by which the fissile isotope ^235U is concentrated for the production of nuclear fuel, generates a waste product that is depleted in both ^235U and ^234U. Depleted uranium （DU） therefore has a distinct isotopic signature that can be used to monitor contamination arising from the use of munitions containing it （i.e., DU weapons and armour）. The UK Ministry of Defense has tested such munitions at coastal locations in SW Scotland and NW England, resulting in possible contamination of the surrounding terrestrial and marine environments. We examined the U isotope distribution in surface soil （top 10 cm） and salt marsh sediment samples from these locations using alpha spectrometry to determine the extent of any DU contamination from the munitions testing programme. Despite 〉30 t of DU shells having been fired into the sea in this region there was no evidence of deviation from the natural ^234U ： ^238U activity ratio range in salt marsh samples. The ^235U ： ^238U activity ratio could not be used to assess these salt marsh samples because ^235U activities were at the limit of detection for alpha spectrometry.     

以减少碳损失为目标的印度大城市可持续林业：以德里地区为例

试图识别德里从大气中固碳的碳源行为以及进一步证明各种造林工程有利于控制碳损失。碳化气的释放来源于城市的各个环节，包括城市的居民生活、工业过程、电力生产和轮船及热源工厂的辐射。这里主要想证明德里的土地利用/覆盖变化通过砍伐森林来进行地铁、立交桥、建筑和其他非森林可持续的城市建设对森林和树木覆盖造成的压力。所有的这些都导致德里的微气候变化，尤其是气温的升高。造林工程可以提供大量的气候变化缓解效应。     

古海啸研究

2004年12月26日印度洋海啸明确证实仅靠历史记录难以显示海啸的危险性。长期地质记录为评估海啸危险提供了更多信息。海啸遗留的沉积证据有助于评估过去洪水的水位深度和速度,估计源头位置,以及帮助了解海啸是如何影响滨海地区的生态和地貌。过去的沉积可以估计历史海啸的次数和重复周期。这些信息对于减轻未来海啸的影响和减少其带来的可能损失具有指导作用。古海啸研究引起了地震地质、古生物学、古生态学、地貌学、海洋物理学、地球物理学、海洋地质学、沉积学、地球化学、地震学、海岸工程学和社会学领域的科学家的兴趣,并可能导致不曾…     

THREE DIMENSIONAL NUMERICAL MODELLING OF FLOW AND SEDIMENT TRANSPORT IN RIVERS

The 3D numerical model, ECOMSED (open source code), was used to simulate flow and sediment transport in rivers. The model has a long history of successful applications to oceanic, coastal and estuarine waters. Improvements in the advection scheme, treatment of river roughness parameterization and shear stress partitioning were necessary to reproduce realistic and comparable results in a river application. To account for the dynamics of the mobile bed boundary, a model for the bed load transport was included in the code. The model reproduced observed secondary currents, bed shear stress distribution and erosion-deposition patterns on a curved channel. The model also successfully predicted the general flow patterns and sediment transport characteristics of a 1-km long reach of the River Klar?lven, located in the north of the county of V?rmland, Sweden.     

新西兰坎特伯里班各斯半岛第四纪黄土沉积物的放射性碳年代测定

研究的背景近来新西兰第四纪黄土的研究,获得了关于黄土沉积作用和有关土壤发育的有用的报告。新西兰黄土最深入细致的研究,集中于提马鲁城周围,并以里赛德的早期工作为开端。这里已认出至少有五层明显的黄土层,它们各以古土壤相隔。     

EXPERT SYSTEM FOR THE CHARACTERIZATION OF LABORATORY SAMPLE INPUT SIGNALS:AUTOCORR

An expert system is presented for automated time series analysis of laboratory sample input signals.Thesystem,AUTOCORR,builds a model of the time series by identifying the processes that are present.These are an uncorrelated random process and,underlying this,possibly one or more of the following:a first-order autoregressive process,a trend and a periodic process.AUTOCORR has a knowledge baseof 44 rules and 41 facts for this purpose.The employed shell,INFER,allows the use of algorithmicprocedures.Elaborate tests with simulated signals show that AUTOCORR has a very low false positivescore and is successful in describing time series for laboratory simulation models.     

A Spectroscopic Redshift for the Cl 0024+16 Multiple Arc System: Implications for the Central Mass Distribution

We show that the energy-level splitting that arises from grain rotation ensures that paramagnetic dissipation acts at its maximum rate, i.e., the conditions for paramagnetic resonance are automatically fulfilled. We refer to this process as "resonance relaxation." The differences between the predictions of classical Davis-Greenstein relaxation and resonance relaxation are most pronounced for grains rotating faster than 1 GHz, i.e., in the domain in which classical paramagnetic relaxation is suppressed. This mechanism can partially align even very small grains, resulting in linearly polarized microwave emission that could interfere with efforts to measure the polarization of the cosmic microwave background.     

eta Carinae: Binarity Confirmed

Gas giant planets have been detected in orbit around an increasing number of nearby stars. Two theories have been advanced for the formation of such planets: core accretion and disk instability. Core accretion, the generally accepted mechanism, requires several million years or more to form a gas giant planet in a protoplanetary disk like the solar nebula. Disk instability, on the other hand, can form a gas giant protoplanet in a few hundred years. However, disk instability has previously been thought to be important only in relatively massive disks. New three-dimensional, "locally isothermal," hydrodynamical models without velocity damping show that a disk instability can form Jupiter-mass clumps, even in a disk with a mass (0.091 M middle dot in circle within 20 AU) low enough to be in the range inferred for the solar nebula. The clumps form with initially eccentric orbits, and their survival will depend on their ability to contract to higher densities before they can be tidally disrupted at successive periastrons. Because the disk mass in these models is comparable to that apparently required for the core accretion mechanism to operate, the models imply that disk instability could obviate the core accretion mechanism in the solar nebula and elsewhere.     

考虑地下水入侵导致土壤强度变化的沿海建筑地基韧性模型

海平面上升导致的地下水入侵沿海地区的建筑地基造成显著风险。提出了一个考虑地下水侵入导致土壤强度退化的沿海建筑地基韧性模型。该模型由地基的性能函数在服役期内的积分得到。考虑条形基础的韧性,其极限承载力由Terzaghi公式描述。韧性模型考虑气候变化背景下地下水位的上升对土壤强度的影响。通过一个算例,展示了所提出的韧性模型的适用性。结果表明,如果不考虑气候变化影响下地下水位的上升,则会得到不保守的结构韧性评估结果。结构全寿命周期内的韧性也取决于所采用的维护措施（即,修复受损的结构性能）。未来的研究中,还应考虑其他因素（如锈蚀）对沿海建筑地基性能退化的联合影响。