The existence of a double S-shaped process curve during reactive magnetron sputtering

The four dimensional parameter space (discharge voltage and current and reactive gas flow and pressure) related to a reactive Ar/O2 DC magnetron discharge with an aluminum target and constant pumping speed was acquired by measuring current-voltage characteristics at different oxygen flows. The projection onto the pressure-flow plane allows us to study the well-known S-shaped process curve. This experimental procedure guarantees no time dependent effects on the result. The obtained process curve appears not to be unique but rather two significantly different S-shaped curves are noticed which depend on the history of the steady state target condition. As such, this result has not only an important impact on the fundamental description of the reactive sputtering process but it can also have its consequences on typical feedback control systems for the operation in the transition regime of the hysteresis during reactive magnetron sputtering

Postpartum amenorrhoea-galactorrhoea associated with hyperprolactinaemia and pituitary enlargement in primary hypothyroidism

We report a 36-year-old woman with primary hypothyroidism revealed by postpartum amenorrhoea-galactorrhoea associated with hyperprolactinaemia and suprasellar pituitary enlargement on magnetic resonance imaging (MRI). On thyroid hormone replacement therapy all clinical, biochemical, radiological and endocrine abnormalities disappeared. Hyperplasia of pituitary thyrotrophs and/or lactotrophs seems to be responsible for the pituitary enlargement seen on MRI

Phytoextraction of phosphorus for ecological restoration: application of soil additives

The European Habitats Directive urges the European member states to take measures for maintaining and restoring natural habitats. In Flanders (Belgium) and the Netherlands, the surface area of nature reserves is intended to be enlarged with 38 000 ha and 150 000 ha, respectively, what is mainly to be realised on former agricultural land. In order to restore species rich nature habitats on former agricultural land, it is crucial to decrease the availability of nutrients and a limitation for plant growth by at least one nutrient should be ensured. The former fertilization of P in the agricultural context results in an immense P pool fixated to the soil and this is one of the main problems hindering the ecological restoration. We focus on an alternative restoration method, the phytoextraction of P, also P-mining. This is the deprivation of soil P with a crop with high P-use efficiency and non-P fertilization. This method allows the gradual transition from agricultural land use towards nature management. Up until now there have only been estimations of the P-mining duration time from the initial phase of the mining-process. In order to estimate the P-extraction over time the experiments take place on a soil-P-chronosequence. A controlled pot experiment was set up with soil from three former agricultural sites with different soil-P-levels, Lolium perenne was sown and chemical and biological compounds were added to enhance the bioavailability of P for plant-uptake. The additives used were two concentrations of humic acids, phosphorus solubilising bacteria and arbuscular mycorrhizal fungi. Largest effects of the soil additions on the biomass production were measured in the lowest soil-P-level. Limitation by P in the Mid and Low P soils was very pronounced. The phytoextraction of P will slow down with soil P level decreasing in time. The effect of the soil additions is discussed

Optimization of PET protocol and interrater reliability of 18F-PSMA-11 imaging of prostate cancer

Background Several scan parameters for PET imaging with F-18-PSMA-11 such as dosage, acquisition time and scan duration were evaluated to determine the most appropriate scan protocol, as well as the effect of furosemide administration on lesion visualization. Forty-four patients were randomly assigned to a dosage group (2.0 +/- 0.2 or 4.0 +/- 0.4 MBq/kg F-18-PSMA-11). All patients received a full-body PET/CT 1 h and 3 h after radiotracer injection with a scan duration of 3 min/bed position. For comparison of the scan duration, images were reconstructed for 1.5 and 3 min/bed position. Patients were intravenously administered 0.5 mg/kg furosemide with a maximum dose of 40 mg. To evaluate the furosemide effect, 22 additional patients were recruited and received one full-body PET/CT 1 h after administration of 2.0 +/- 0.2 MBq/kg F-18-PSMA-11 with a scan duration of 3 min/bed position. To this group, no furosemide was administered. Images were scored on image quality using a 7-point scale and each suspicious lesion was described. To assess interrater reliability, two nuclear physicians scored all scans independently and described all observed suspicious lesions. Results The 4 MBq/kg group received for all reconstructed images (60 min p.i., 1.5 and 3 min/bed position and 180 min p.i., 1.5 and 3 min/bed position) the highest median image quality score compared to the 2 MBq/kg group (p values < 0.01). When comparing all reconstructed images, the highest image quality score was given to images at 60 min p.i., 3 min/bed position for both dosage groups (score 5 and 6 for 2 and 4 MBq/kg, respectively). The addition of furosemide administration decreased the interference score with one point (p = 0.01106) and facilitated the evaluation of lesions in proximity to the ureters. The interrater reliability for the comparison of each lesion separately after more than 40 F-18-PSMA-11 scan readings showed an increasing kappa value from 0.78 (95% CI, 0.65-0.92) to 0.94 (95% CI, 0.87-1). Conclusion Although the results indicate an administered activity of 4.0 +/- 0.4 MBq/kg, preference will be given to 2.0 +/- 0.2 MBq/kg due to the small difference in absolute score (max 1 point) and the ALARA principle. For evaluation of lesions in proximity to the ureters, the co-administration of a diuretic can be useful. The increase of the kappa value from 0.78 to 0.94 suggests a learning curve in the interpretation of F-18-PSMA-11 images

NIP Fondatie-Heernisse: expertenadvies vegetatieontwikkeling

Binnen het natuurinrichtingsproject (NIP) Fondatie-Heernisse wordt bekeken wat de potenties zijn voor vegetatieontwikkeling van soortenrijke natuur (blauwgrasland, dotterbloemgrasland, ...) op voormalige landbouwgrond. De huidige aanrijking met nutriënten en de hydrologie worden in detail in kaart gebracht en passende herstelmaatregelen (afgraven, uitmijnen van fosfor, maaibeheer) worden besproken