The effect of tyres and a rubber track at high axle loads on soil compaction-Part 2: Multi-axle machine studies

This paper reports on a study of the effect of the passage of multi-axle harvesting machines on the soil physical properties. In particular, it investigates the effect of the rear tyre of a combine harvester on the amount of soil compaction subsequent to the passage of the front tyre/track. The work was conducted in controlled laboratory conditions to determine the effect of a simulated self-propelled combine harvester with a total machine weight of 30–33 t. This was assessed by embedding talcum powder tracer lines in the soil to measure soil displacement and soil density changes. Dry bulk density and penetrometer resistance were also measured. The results showed that the benefit of the rubber track found by Ansorge and Godwin [2007a. The effect of tyres and a rubber track at high axle loads on soil compaction: Part 1: Single Axle Studies. Biosystems Engineering 98 (1), 115–126] was maintained after the additional passage of the rear tyre. After the passage of a track the effect of rear tyre size was insignificant, but the rear tyre size had a significant influence on soil density when following a leading tyre. This was due to a higher strength layer at the soil surface created by the track which was able to withstand the load of the subsequent passes and protect the soil below from further compaction. Results similar to those found for a tracked machine were also achieved by three passes of a 900 mm section width tyre at 5 t load and 0.5 bar inflation pressure. The track results for the 33 t machine were very similar to those of a smaller combine harvester with a total load of 11 t and similar rut width. The study confirmed the benefit of tracks with regard to soil compaction and emphasised the fact that total axle loads and machine weights are less important than how the loads are distributed to the soil

Forward-Backward Multiplicity Correlations in Au+Au Collisions at sNN\sqrt{s_{NN}} = 200 Gev

The study of correlations among particles produced in different rapidity regions may provide understanding of the mechanisms of particle production. Correlations that extend over a longer range are observed in hadron-hadron interactions only at higher energies. Results for short and long-range multiplicity correlations (Forward-Backward) are presented for Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The growth of long range correlations are observed as a function of the pseudorapidity gap in central Au+Au collisions. The Dual Parton model and Color Glass Condensate phenomenology have been explored to understand the origin of long range correlations.Comment: 8 pages, 4 figures, IWCF06, Hangzhou, China, Nov. 21-24, 200

Two new Lower Cretaceous hymenopterous insects (Insecta: Hymenoptera) from Sierra del Montsec, Spain

Two new hymenoterans are described from the Lower Barremian lithographic limestones of Sierra del Montsec (Lleida, Spain), Leridatoma pulcherrimapulcherima n.gen., n.sp. (Xyelotomidae RASNITSYN, 1968) that combines the most and the least advanced character states in the family (in structure of antenna and fore wing RS, respectively), and Cretephialtites pedrerae n.gen., n.sp. (Ephialtitidae HANDLIRSCH, 1906)

The Conrad Rise as an obstruction to the Antarctic Circumpolar Current

The Antarctic Circumpolar Current (ACC) carries water freely around the whole continent of Antarctica, but not without obstructions. Some, such as the Drake Passage, constrict its path, while others, such as mid-ocean ridges, may induce meandering in the current's cores and may cause the genesis of mesoscale turbulence. It has recently been demonstrated that some regions that are only relatively shallow may also have a major effect on the flow patterns of the ACC. This is here shown to be particularly true for the Conrad Rise. Using the trajectories of surface drifters, altimetry and the simulated velocities from a numerical model, we show that the ACC bifurcates at the western side of this Rise. In this process it forms two intense jets at the two meridional extremities of the Rise with a relatively stagnant water body over the Rise itself. Preliminary results from a recent cruise provide compelling support for this portrayal

Oceanographic observations of eddies impacting the Prince Edward Islands, South Africa

The ecosystem of the isolated Prince Edward Islands, south of the African continent, is strongly impacted by ocean eddies that are associated with the eastward flowing Antarctic Circumpolar Current. Satellite altimetry has revealed that the archipelago lies in a region of enhanced eddy kinetic energy. In the late 1990s it became apparent that in order to understand the influence of these eddies on the islands' ecosystem, the source, trajectory and nature of these eddies needed to be studied and understood. To this end a special research project with a strong ocean-going component was designed, the DEIMEC (Dynamics of Eddy Impact on Marion's ECosystem) programme. In this review we focus on the physical oceanography and summarize the aims, the results and the successes of this South African research initiative. In the vicinity of the Prince Edward Islands, an average of three intense well-defined eddies is observed per year. Their advection speeds are of the order of a few kilometres per day and longevities of 7-11 months. These features, of c. 100 km in diameter and reaching depths of at least 1000 m, transport anomalous water masses across the Polar Frontal Zone

Studying the impact of ocean eddies on the ecosystem of the Prince Edward Islands: DEIMEC ll

The Dynamics of Eddy Impacts on Marion’s Ecosystem Study (DEIMEC) programme was begun in 2002 with the aim of understanding the importance of the oceanic, upstream environment to the ecosystem of the Prince Edward Islands. This island group consists of two small volcanic islands and provides many opportunities for studying ecological and evolutionary processes, for monitoring ecological changes in relation to global climate change and for conserving a unique component of the planet’s biological diversity

Three dimensional interface modelling with two-dimensional seismic data: the Alpine crust-mantle boundary

We present a new approach to determine the 3-D topography and lateral continuity of seismic interfaces using 2-D-derived controlled-source seismic reflector data. The aim of the approach is to give the simplest possible structure consistent with all reflector data and error estimates. We define simplicity of seismic interfaces by the degree of interface continuity (i.e. shortest length of offsets) and by the degree of interface roughness (least surface roughness). The method is applied to structural information of the crust—mantle boundary (Moho) obtained from over 250 controlled-source seismic reflection and refraction profiles in the greater Alpine region. The reflected and refracted phases from the Moho interface and their interpretation regarding crustal thickness are reviewed and their reliability weighted. Weights assigned to each reflector element are transformed to depth errors considering Fresnel volumes. The 2-D-derived reflector elements are relocated in space (3-D migration) and interpolation is performed between the observed reflector elements to obtain continuity of model parameters. Interface offsets are introduced only where required according to the principle of simplicity. The resulting 3-D model of the Alpine crust—mantle boundary shows two offsets that divide the interface into a European, an Adriatic and a Ligurian Moho, with the European Moho subducting below the Adriatic Moho, and with the Adriatic Moho underthrusting the Ligurian Moho. Each sub-interface depicts the smoothest possible (i.e. simplest) surface, fitting the reflector data within their assigned errors. The results are consistent with previous studies for those regions with dense and reliable controlled-source seismic data. The newly derived Alpine Moho interface, however, surpasses earlier studies by its lateral extent over an area of about 600 km by 600 km, by quantifying reliability estimates along the interface, and by obeying the principle of being consistently as simple as possibl

Sentinels to climate change. The need for monitoring at South Africa’s Subantarctic laboratory

The International Society for Burns Injuries (ISBI) has published guidelines for the management of multiple or mass burns casualties, and recommends that 'each country has or should have a disaster planning system that addresses its own particular needs.' The need for a national burns disaster plan integrated with national and provincial disaster planning was discussed at the South African Burns Society Congress in 2009, but there was no real involvement in the disaster planning prior to the 2010 World Cup; the country would have been poorly prepared had there been a burns disaster during the event. This article identifies some of the lessons learnt and strategies derived from major burns disasters and burns disaster planning from other regions. Members of the South African Burns Society are undertaking an audit of burns care in South Africa to investigate the feasibility of a national burns disaster plan. This audit (which is still under way) also aims to identify weaknesses of burns care in South Africa and implement improvements where necessary

Identity of Prosepididontus calpterys Handlirsch 1920 (Insecta: Grylloblattida: Geinitziidae)

Prosepididontus calopteryx HANDLIRSCH 1920, from the upper Lower Jurassic of Germ a ny, is transferred from Trichoptera to Grylloblattida: Geinitziidae. The anal loop like structure of Prosepididontus calopteryx is built of the concave CuP and two anal veins. Prosepididontidae HANDLIRSCH, 1920 is synonymised under Geinitziidae HANDLIRSCH, 1906.Prosepididontus calopteryx HANDLIRSCH 1920, from the upper Lower Jurassic of Germ a ny, is transferred from Trichoptera to Grylloblattida: Geinitziidae. The anal loop like structure of Prosepididontus calopteryx is built of the concave CuP and two anal veins. Prosepididontidae HANDLIRSCH, 1920 is synonymised under Geinitziidae HANDLIRSCH, 1906