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The Nitrate Directive of the European Union (EU) forces agriculture to reduce nitrate emission. The current study addressed nitrate emission and nitrate-N concentrations in leachate from cropping systems with and without the cultivation of catch crops (winter rye: Secale cereale L. and forage rape: Brassica napus ssp. oleifera (Metzg.) Sinksk). For this purpose, ceramic suction cups were used, installed at 80 cm below the soil surface. Soil water samples were extracted at intervals of ca 14 days over the course of three leaching seasons (September – February) in 1992–1995 on sandy soil in a crop rotation comprising potato (Solanum tuberosum L.), spring wheat (Triticum aestivum L.), sugar beet (Beta vulgaris L.) and oats (Avena sativa L.). Nitrate-N concentration was determined in the soil water samples. In a selection of samples several cations and anions were determined in order to analyze which cations primarily leach in combination with nitrate. The water flux at 80 cm depth was calculated with the SWAP model. Nitrate-N loss per interval was obtained by multiplying the measured nitrate-N concentration and the calculated flux. Accumulation over the season yielded the total nitrate-N leaching and the seasonal flux-weighted nitrate-N concentration in leachate. Among the cases studied, the total leaching of nitrate-N ranged between 30 and 140 kg ha–1. Over the leaching season, the flux-weighted nitrate-N concentration ranged between 5 and 25 mg L–1. Without catch crop cultivation, that concentration exceeded the EU nitrate-N standard (11.3 mg L–1) in all cases. Averaged for the current rotation, cultivation of catch crops would result in average nitrate-N concentrations in leachate near or below the EU nitrate standard. Nitrate-N concentrations correlated with calcium concentration and to a lesser extent with magnesium and potassium, indicating that these three ion species primarily leach in combination with nitrate. It is concluded that systematic inclusion of catch crops helps to decrease the nitrate-N concentration in leachate to values near or below the EU standard in arable rotations on sandy soils.

Three different techniques were evaluated for installing suction cups in an alluvial gravel vadose zone—a steel spike, a mechanical auger, and an air rotary drilling rig. Soil water samples were collected from suction cups monthly for three years. Nitrate and chloride concentrations in samples taken from the suction cups were similar to those measured from a linear lysimeter installed in the same field. The nitrate and chloride concentrations in the suction cup samples showed significant spatial and temporal variation consistent with leaching from random urine patches. Solute concentrations became less variable as sampling depth increased, so fewer suction cups would be required at greater depths to estimate mean concentrations of solutes leaching to groundwater. Recharge was estimated using a water balance model and combined with the concentration data to give solute fluxes or leaching losses. Averaging the fluxes from all of the suction cups indicates a fairly constant leaching loss of around 50 kg ha⁻¹yr⁻¹ for nitrate-N (range = 38-58 kg ha⁻¹yr⁻¹) and around 80 kg ha⁻¹yr⁻¹ for chloride (range = 79-89kg ha⁻¹yr⁻¹). The total cost for the construction and installation of the suction cups ranged from $290 for the 1.3 m depth spike installation to $620 for the 5 m depth suction cups installed using an air rotary drilling rig. The major difference in price between the three installation methods relates to their depth limitations and the higher cost of equipment that can install suction cups at greater depths. A significant limitation of the auger installation was the disturbance of the soil profile caused by the large diameter hole that was excavated. For the installation of suction cups in stony alluvial sub-soils, we recommend using spike installation for depths of less than 1.5 m and air rotary drilling for depths of greater than 1.5 m.

The use of 3D-printed highly porous titanium acetabular cups in total hip arthroplasty (THA) is increasing. The porosity and mechanical properties of such highly porous titanium structures mimic those of natural cancellous bone, possibly allowing biological implant fixation to be improved. Recently, a 3D-printed highly porous Dual Mobility (DM) monobloc construct fully manufactured using Ti6Al4V alloy, with a titanium–niobium nitride (TiNbN) ceramic coating on the articular side to allow articulation against the mobile liner by improving the titanium vs. polyethylene tribological behavior, was introduced in THA. To the best of our knowledge, this is the first highly porous titanium monobloc DM implant on the market. The reasons for using a Ti alloy highly porous DM are multifarious: to prevent any possible adverse reactions due to the corrosion of Cobalt–Chromium–Molybdenum Alloy (CoCrMo) and Stainless Steel (SS) implants and to improve implant primary and secondary stability, particularly in cases of poor bone quality. Finally, with the introduction of an inner TiNbN ceramic coating surface, it was possible to overcome the poor tribological quality of titanium. Another interesting characteristic is this material’s higher implant radiolucency, which might facilitate the radiographic assessment of cup orientation, which can, in turn, facilitate the detection of any intraprosthetic dislocation (IPD) and the measurement of polyethylene wear, which is very important in the study of the durability of THA.

The aim of this study was to evaluate the long-term outcome of cementless acetabular cups used in primary total hip arthroplasty. From November 1993 to December 1998, we implanted 403 cementless acetabular cups. Here we present a review of 160 patients (97 women) who received cementless acetabular cups with a porous-coated surface. The average postoperative follow-up period was 6 years (range, 4-8 years). The mean age of patients was 68 years for cemented stems (65 hips) and 59 for uncemented stems (95 hips). A total of 104 patients received ceramic-polyethylene components and 56 had ceramic-ceramic components. One patient presented acetabular migration and needed revision after 5 months indicating a failure rate of 0.6%. We believe that our results provides quite good perspectives for future work with this acetabular component.[PUBLICATION ABSTRACT]