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61.
C. Block B. Van Praet T. Windels I. Vermeulen G. Dangreau A. Overmeire E. D’Hooge T. Maes G. Van Eetvelde C. Vandecasteele 《Journal of Industrial Ecology》2011,15(4):584-596
The industrial park of Herdersbrug (Brugge, Flanders, Belgium) comprises 92 small and medium‐sized enterprises, a waste‐to‐energy incinerator, and a power plant (not included in the study) on its site. To study the carbon dioxide (CO2) neutrality of the park, we made a park‐wide inventory for 2007 of the CO2 emissions due to energy consumption (electricity and fossil fuel) and waste incineration, as well as an inventory of the existing renewable electricity and heat generation. The definition of CO2 neutrality in Flanders only considers CO2 released as a consequence of consumption or generation of electricity, not the CO2 emitted when fossil fuel is consumed for heat generation. To further decrease or avoid CO2 emissions, we project and evaluate measures to increase renewable energy generation. The 21 kilotons (kt) of CO2 emitted due to electricity consumption are more than compensated by the 25 kt of CO2 avoided by generation of renewable electricity. Herdersbrug Industrial Park is thus CO2 neutral, according to the definition of the Flemish government. Only a small fraction (6.6%) of the CO2 emitted as a consequence of fossil fuel consumption (heat generation) and waste incineration is compensated by existing and projected measures for renewable heat generation. Of the total CO2 emission (149 kt) due to energy consumption (electricity + heat generation) and waste incineration on the Herdersbrug Industrial Park in 2007, 70.5% is compensated by existing and projected renewable energy generated in the park. Forty‐seven percent of the yearly avoided CO2 corresponds to renewable energy generated from waste incineration and biomass fermentation. 相似文献
62.
Nick R Love Yaoyao Chen Boyan Bonev Michael J Gilchrist Lynne Fairclough Robert Lea Timothy J Mohun Roberto Paredes Leo AH Zeef Enrique Amaya 《BMC developmental biology》2011,11(1):1-15
Background
During liver development, intrahepatic bile ducts are thought to arise by a unique asymmetric mode of cholangiocyte tubulogenesis characterized by a series of remodeling stages. Moreover, in liver diseases, cells lining the Canals of Hering can proliferate and generate new hepatic tissue. The aim of this study was to develop protocols for three-dimensional visualization of protein expression, hepatic portal structures and human hepatic cholangiocyte tubulogenesis.Results
Protocols were developed to digitally visualize portal vessel branching and protein expression of hepatic cell lineage and extracellular matrix deposition markers in three dimensions. Samples from human prenatal livers ranging from 7 weeks + 2 days to 15½ weeks post conception as well as adult normal and acetaminophen intoxicated liver were used. The markers included cytokeratins (CK) 7 and 19, the epithelial cell adhesion molecule (EpCAM), hepatocyte paraffin 1 (HepPar1), sex determining region Y (SRY)-box 9 (SOX9), laminin, nestin, and aquaporin 1 (AQP1). Digital three-dimensional reconstructions using CK19 as a single marker protein disclosed a fine network of CK19 positive cells in the biliary tree in normal liver and in the extensive ductular reactions originating from intrahepatic bile ducts and branching into the parenchyma of the acetaminophen intoxicated liver. In the developing human liver, three-dimensional reconstructions using multiple marker proteins confirmed that the human intrahepatic biliary tree forms through several developmental stages involving an initial transition of primitive hepatocytes into cholangiocytes shaping the ductal plate followed by a process of maturation and remodeling where the intrahepatic biliary tree develops through an asymmetrical form of cholangiocyte tubulogenesis.Conclusions
The developed protocols provide a novel and sophisticated three-dimensional visualization of vessels and protein expression in human liver during development and disease. 相似文献63.
Bernatchez L St-Cyr J Normandeau E Maes GE Als TD Kalujnaia S Cramb G Castonguay M Hansen MM 《Ecology and evolution》2011,1(4):459-467
The unique life-history characteristics of North Atlantic catadromous eels have long intrigued evolutionary biologists, especially with respect to mechanisms that could explain their persistence as two ecologically very similar but reproductively and geographically distinct species. Differential developmental schedules during young larval stages have commonly been hypothesized to represent such a key mechanism. We performed a comparative analysis of gene expression by means of microarray experiments with American and European eel leptocephali collected in the Sargasso Sea in order to test the alternative hypotheses of (1) differential timing of gene expression regulation during early development versus (2) species-specific differences in expression of particular genes. Our results provide much stronger support for the former hypothesis since no gene showed consistent significant differences in expression levels between the two species. In contrast, 146 genes showed differential timings of expression between species, although the observed expression level differences between the species were generally small. Consequently, species-specific gene expression regulation seems to play a minor role in species differentiation. Overall, these results show that the basis of the early developmental divergence between the American and European eel is probably influenced by differences in the timing of gene expression regulation for genes involved in a large array of biological functions. 相似文献
64.
Nwaka S Besson D Ramirez B Maes L Matheeussen A Bickle Q Mansour NR Yousif F Townson S Gokool S Cho-Ngwa F Samje M Misra-Bhattacharya S Murthy PK Fakorede F Paris JM Yeates C Ridley R Van Voorhis WC Geary T 《PLoS neglected tropical diseases》2011,5(12):e1412
New chemical entities are desperately needed that overcome the limitations of existing drugs for neglected diseases. Screening a diverse library of 10,000 drug-like compounds against 7 neglected disease pathogens resulted in an integrated dataset of 744 hits. We discuss the prioritization of these hits for each pathogen and the strong correlation observed between compounds active against more than two pathogens and mammalian cell toxicity. Our work suggests that the efficiency of early drug discovery for neglected diseases can be enhanced through a collaborative, multi-pathogen approach. 相似文献
65.
A. Maes A. Hilali E. D. Léonard A. Léonard L. Verschaeve 《Radiation and environmental biophysics》1993,32(4):319-324
A thorough cytogenetic analysis using G-banding was performed on 100 peripheral blood lymphocytes from an individual who had been accidentally exposed to radiation more than 25 years previously. More than 60% of the analysed cells were found to possess one or more stable chromosome aberrations (e.g. reciprocal translocations). Chromosomes 1 and 11 were more involved in these aberrations than would be expected from the relative chromosome lengths. No identical stable aberrations were found, suggesting that, 25 years after nearlethal exposure, haemopoietic stem cells display substantial diversity. 相似文献
66.
There is now evidence that major depression is accompanied by decreased levels of omega3 poly-unsaturated fatty acids (PUFA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). There is a strong comorbidity between major depression and chronic fatigue syndrome (CFS). The present study has been carried out in order to examine PUFA levels in CFS. In twenty-two CFS patients and 12 normal controls we measured serum PUFA levels using gas chromatography and mass spectrometry. We found that CFS was accompanied by increased levels of omega6 PUFAs, i.e. linoleic acid and arachidonic acid (AA), and mono-unsaturated fatty acids (MUFAs), i.e. oleic acid. The EPA/AA and total omega3/omega6 ratios were significantly lower in CFS patients than in normal controls. The omega3/omega6 ratio was significantly and negatively correlated to the severity of illness and some items of the FibroFatigue scale, i.e. aches and pain, fatigue and failing memory. The severity of illness was significantly and positively correlated to linoleic and arachidonic acid, oleic acid, omega9 fatty acids and one of the saturated fatty acids, i.e. palmitic acid. In CFS subjects, we found significant positive correlations between the omega3/omega6 ratio and lowered serum zinc levels and the lowered mitogen-stimulated CD69 expression on CD3+, CD3+ CD4+, and CD3+ CD8+ T cells, which indicate defects in early T cell activation. The results of this study show that a decreased availability of omega3 PUFAs plays a role in the pathophysiology of CFS and is related to the immune pathophysiology of CFS. The results suggest that patients with CFS should respond favourably to treatment with--amongst other things--omega3 PUFAs, such as EPA and DHA. 相似文献
67.
Vanholder T Leroy JL Soom AV Opsomer G Maes D Coryn M de Kruif A 《Animal reproduction science》2005,87(1-2):33-44
In high-yielding dairy cows, the negative energy balance (NEB) during the first weeks post partum may influence dominant follicle growth and steroidogenesis. Since non-esterified fatty acid (NEFA) concentrations are elevated during NEB and are shown to be toxic for several cell types, we investigated the individual and combined effects of the three main NEFA's on granulosa cell proliferation and steroidogenesis in vitro. Granulosa cells from large follicles were cultured for two days in serum free medium in the presence of palmitic (C16:0) (PA), stearic (C18:0) (SA) and/or oleic acid (C18:1) (OA). Addition of 150, 300 or 500 microM of PA and SA inhibited cell proliferation (P<0.05) while OA only elicited such an effect at 500 microM (P<0.01). In the combination treatment (150 microM of each fatty acid), cell numbers were also reduced (P<0.01). These inhibitory effects on cell number are partly due to the induction of apoptosis by these NEFA's, as was demonstrated by annexin V-FITC/propidium iodide staining of the granulosa cells. Oestradiol-17beta production was stimulated by all doses of PA, by 300 and 500 microM of SA and by 500 microM of OA (P<0.05). Combined treatment with 150 microM of each fatty acid also stimulated oestradiol-17beta production per 10(4) cells (P<0.05). We can conclude that PA, SA and to a lesser degree OA modulate granulosa cell proliferation and steroidogenesis in vitro. These effects may be involved in the occurrence of ovarian dysfunction during the postpartum period in high-yielding dairy cows. 相似文献
68.
The cyclin-dependent kinase inhibitor KRP2 controls the onset of the endoreduplication cycle during Arabidopsis leaf development through inhibition of mitotic CDKA;1 kinase complexes 下载免费PDF全文
Verkest A Manes CL Vercruysse S Maes S Van Der Schueren E Beeckman T Genschik P Kuiper M Inzé D De Veylder L 《The Plant cell》2005,17(6):1723-1736
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