Production and performance of bio-based mineral fertilizers from agricultural waste using ammonia (stripping-)scrubbing technology.

Development and optimization of nutrient recovery technologies for agricultural waste is on the rise. The full scale adoption of these technologies is however hindered by complex legal aspects that result from lack of science-based knowledge on characterization and fertilizer performance of recovered end-products. Ammonium sulfate (AS) and ammonium nitrate (AN), end-products of (stripping-)scrubbing technology, are currently listed by the European Commission as high priority products with the potential of replacing synthetic N fertilizers. The legal acceptance of AS and AN will be highly dependent on critical mass of scientific evidence. This study describes four different (stripping-)scrubbing pathways to recover ammonia with an aim to (i) assess product characteristics of ammonium nitrate (AN) and ammonium sulfate (AS) produced from different installations, (ii) evaluate fertilizer performance of recovered end-products in greenhouse (Lactuca sativa L.) and full field (Zea mays L.) scale settings and (iii) compare the observed performances with other published studies. Results have indicated that the recovered products might have a different legal status, as either mineral N fertilizer or yet as animal manure, depending on the used (stripping-)scrubbing process pathway. Nevertheless, no significant differences in respect to product characterization and fertilizer performance of AN and AS have been identified in this study as compared to the conventional use of synthetic N fertilizers. This indicates that recovered AS and AN are valuable N sources and therefore might be used as N fertilizers in crop cultivation.

Haemophilus influenzae: a forgotten cause of neonatal sepsis?

Due to the introduction of the conjugate vaccine against serotype b, neonatal sepsis caused by Haemophilus influenzae became very rare. There is little data in Belgium concerning the prevalence of H. influenzae early onset neonatal sepsis and articles about neonatal sepsis and H. influenzae published in the last decade are scarce. We report two invasive infections with a non-typeable H. influenzae. These cases show that neonatal sepsis caused by non-typeable H. influenzae may be underestimated and we believe that there is need for a better registration of this kind of infection.

Production and characterisation of monoclonal antibodies specific for bovine interleukin-4.

Genetic immunisation is a simple method for producing polyclonal antibodies in mice. By this method, we produced antibodies against bovine interleukin-4 (BoIL-4). After a final injection with a recombinant BoIL-4 protein, nine stable hybridoma cell lines were established which secreted monoclonal antibodies (MAbs) against this cytokine. Specific binding of each of the MAbs to recombinant BoIL-4 produced by Escherichia coli, baculovirus, and Trypanosoma brucei was demonstrated in an indirect ELISA and/or in Western blotting. These MAbs recognise the same antigenic region localised in the first 47 amino acids of the mature protein. None of them was able to neutralise the biological activity of the BoIL-4 under the conditions tested but one allowed the detection of BoIL-4 by flow cytometry.

The potential for preventing the delivery and perinatal mortality of low-birth-weight babies in a black urban population.

OBJECTIVE: To determine the potential for preventing the delivery and perinatal mortality of low-birth-weight (LBW) babies in a black urban population. DESIGN: Cross-sectional descriptive study. SETTING: All women delivering babies weighing less than 2,500 g at Kalafong Hospital in a 6-month period (December 1991-May 1992). MAIN OUTCOME MEASURES: The primary obstetric reason for delivery; whether the labour was of spontaneous onset or iatrogenic; whether labour was theoretically preventable using currently accepted practice; the number of patients in whom suppression of delivery was attempted in the theoretically preventable group; and the perinatal mortality rate of that group. RESULTS: There were 124 perinatal deaths (22.5%) in the 550 LBW babies delivered from 465 singleton pregnancies, 42 twin pregnancies and 1 triplet pregnancy. The primary obstetric reasons for delivery were spontaneous preterm labour (28%), hypertensive diseases (19%), premature rupture of membranes (18%), spontaneous labour in light-for-gestational-age babies (16%), unexplained intra-uterine deaths (8%), antepartum haemorrhage (8%) and other causes (3%). A medical decision to terminate the pregnancy before labour was made in 177 (34.8%) cases, the major reason being hypertensive diseases (84 mothers; 47.5%). In the remaining 331 mothers with spontaneous onset of labour, labour was theoretically preventable in 63 (19%) and prevention was only attempted in 12 (2.4% of the total mothers). The major reason for not attempting to suppress labour in the others was that the patients arrived too late at the hospital for intervention to take place. CONCLUSION: Hospital staff can do little to prevent the delivery of LBW babies in a black urban population.