African Land Ecology: Opportunities and Constraints for Agricultural Development

Current agriculture in Sub-Sahara Africa is undeveloped and the Green Revolution has left the continent largely untouched. Poor performance is often related to a number of socio-economic factors. In this paper we argue that there are also some specifities of natural resources, namely local homogeneity and spatial diversity of the pre-dominant Basement Complex soils, that imply that simple fertilizer strategies may not produce the yield increases obtained elsewhere. Keywords: Sub-Sahara Africa, Agro-Ecology, Land use, Land resources, Basement Complex, Green Revolution, Micronutrients, Fertilizer Policy

De ontwikkeling van een electrostatische windenergie convertor I: samengevat eindrapport van EET KIEM01001/4800000253 Periode 1 Jan 2002 – 31 December 2002

In het EET-project “De ontwikkeling van een Elektrostatische Energie Convertor” kortweg EWICON genoemd is het principe van deze generator theoretisch en experimenteel onderzocht. Het doel van dit kiemproject was de haalbaarheid van het EWICON principe aan te tonen. Experimenteel is de werking van het EWICON principe aangetoond. De experimentele resultaten van het kiemproject hebben verder geleid tot een werkende EWICON model waarbij een door accu’s gevoede invertor een relatief eenvoudige en goedkope manier gevonden is om de geladen ring te voeden bij het aangepaste principe (test 2 en 3). Als materiaalkeuze voor de onderdelen is gekozen voor met tweecomponenten gecoate stalen onderdelen. Hierdoor zijn de onderdelen tegen lage kosten te vervaardigen, hebben ook in zoutwater omstandigheden een lange levensduur en zijn goed recyclebaar

Electricity Generation using Sulfolobus solfataricus in a High-Temperature Microbial Fuel Cell

Microbial fuel cells (MFCs) are a developing technology that breaks down organic materials in liquids while generating electricity. They come in several forms and applications, including: micro-sized for medical implants, sediment for remote sensing and communications, and large-scale for industrial or environmental remediation. Few studies have looked at MFCs operating over 45ºC. Use of extremophiles as the fuel cell culture allows for high-temperature applications including industry, deserts, and alien space environments. This project includes the construction and operation of a membrane-less single chamber microbial fuel cell (ML-SCMFC), using the hyperthermophilic archaeon Sulfolobus solfataricus at about 80°C. The volcanic spring native S. solfataricus was used within a MFC to demonstrate feasibility of an extremely high temperature MFC and characterize the electrical power parameters from this device. A maximum power density of 25.26 mWm-3 was obtained using a carbon cloth anode and cellobiose as the substrate. Maximum sustained current densities ranging from 5.63 and 39.9 mAm-2 persisted for 15-30 hour durations. Continued modifications can potentially improve observed values, including new substrates, inclusion of separators and new anode materials.https://ecommons.udayton.edu/stander_posters/1013/thumbnail.jp

Survival from testicular cancer in England and Wales up to 2001

www.bjcancer.com For many years testicular cancer has been the prime example of the tumour that is chemocurable, even when metastatic. The disappointment in oncology is that these results have so far not been replicated in the more common solid tumours. Why this should be is not clear but germ-cell tumours retain sensitivity to chemotherapy in vitro and a number of mechanisms including reduced DNA repair capacity and proneness to apoptosis have been proposed (Mayer et al, 2003). Most patients with testicular cancer present after finding a lump in the testicle that may or may not be painful. A small proportion of patients present with symptoms of metastatic disease. With the exception of some patients with metastatic disease, initial treatment after first assessment is to remove the tumour by inguinal orchidectomy. Patients are staged by tumour marke

Cancer Stemness in Apc- vs. Apc/KRAS-Driven Intestinal Tumorigenesis

Constitutive activation of the Wnt pathway leads to adenoma formation, an obligatory step towards intestinal cancer. In view of the established role of Wnt in regulating stemness, we attempted the isolation of cancer stem cells (CSCs) from Apc- and Apc/KRAS-mutant intestinal tumours. Whereas CSCs are present in Apc/KRAS tumours, they appear to be very rare (®-catenin intracellular stabilization

Time-trends in disease characteristics and comorbidities in patients with chronic hepatitis B in the period 1980–2020

Background & aims: The incidence of chronic hepatitis B (CHB) is declining due to successful implementation of vaccination programs and widespread use of antiviral therapy. We aimed to study time-trends in disease characteristics and comorbidities in newly referred CHB patients. Methods: : We collected information on hepatitis B virus (HBV) related disease characteristics (including hepatitis B e-antigen (HBeAg) status, viremia, stage of liver fibrosis and indication for treatment and/or hepatocellular carcinoma (HCC) surveillance) and presence of comorbidities in all CHB patients referred to our center from 1980 through 2020. Patient characteristics were compared according to referral date (before 2000, between 2000 and 2010 and after 2010). Results: : We identified 1515 eligible patients. Patients referred after 2010 were older (36 versus 34 years, p < 0.001), more often non-Caucasian (82.3% versus 55.0%, p < 0.001) and more frequently HBeAg negative (81.5% versus 49.8%, p < 0.001) when compared to patients referred before 2000. Adjusted for ethnicity, sex and age, patients referred after 2010 were less likely to have significant fibrosis (adjusted odds ratio [aOR]:0.178, p < 0.001) or indication for antiviral therapy (aOR:0.342, p < 0.001) but were more likely to be affected by the metabolic syndrome (aOR:1.985, p = 0.013), hepatic steatosis (aOR:1.727, p < 0.001) and metabolic dysfunction associated fatty liver disease (MAFLD) (aOR:1.438, p = 0.013). Conclusions: : The characteristics of the CHB populations are changing. Newly referred patients are older, have less active HBV related liver disease but are more likely to be co-affected by MAFLD. These findings provide guidance for adequate allocation of resources to cope with the changing characteristics of the CHB population

MDR1 gene-related clonal selection and P-glycoprotein function and expression in relapsed or refractory acute myeloid leukemia

The expression of P-glycoprotein (P-gp), encoded by the MDR1 gene, is an independent adverse prognostic factor for response and survival in de novo acute myeloid leukemia (AML). Little is known about MDR1 expression during the development of disease. The present study investigated whether MDR1 gene- related clonal selection occurs in the development from diagnosis to relapsed AML, using a genetic polymorphism of the MDR1 gene at position 2677. Expression and function of P-gp were studied using monoclonal antibodies MRK16 and UIC2 and the Rhodamine 123 retention assay with or without PSC 833. No difference was found in the levels of P-gp function and expression between diagnosis and relapse in purified paired blast samples from 30 patients with AML. Thirteen patients were homozygous for the genetic polymorphism of MDR1 (n = 7 for guanine, n = 6 for thymidine), whereas 17 patients were heterozygous (GT). In the heterozygous patients, no selective loss of one allele was observed at relapse. Homozygosity for the MDR1 gene (GG or TT) was associated with shorter relapse-free intervals (P =.002) and poor survival rates (P =.02), compared with heterozygous patients. No difference was found in P-gp expression or function in patients with AML with either of the allelic variants of the MDR1 gene. It was concluded that P-gp function or expression is not upregulated at relapse/refractory disease and expression of one of the allelic variants is not associated with altered P-gp expression or function in AML, consistent with the fact that MDR1 gene-related clonal selection does not occur when AML evolves to recurrent disease. (Blood. 2001;97:3605-3611