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Selected AbstractsMolecular bacterial community analysis of clean rooms where spacecraft are assembledFEMS MICROBIOLOGY ECOLOGY, Issue 3 2007Christine Moissl Abstract Molecular bacterial community composition was characterized from three geographically distinct spacecraft-associated clean rooms to determine whether such populations are influenced by the surrounding environment or the maintenance of the clean rooms. Samples were collected from facilities at the Jet Propulsion Laboratory (JPL), Kennedy Space Flight Center (KSC), and Johnson Space Center (JSC). Nine clone libraries representing different surfaces within the spacecraft facilities and three libraries from the surrounding air were created. Despite the highly desiccated, nutrient-bare conditions within these clean rooms, a broad diversity of bacteria was detected, covering all the main bacterial phyla. Furthermore, the bacterial communities were significantly different from each other, revealing only a small subset of microorganisms common to all locations (e.g. Sphingomonas, Staphylococcus). Samples from JSC assembly room surfaces showed the greatest diversity of bacteria, particularly within the Alpha - and Gammaproteobacteria and Actinobacteria. The bacterial community structure of KSC assembly surfaces revealed a high presence of proteobacterial groups, whereas the surface samples collected from the JPL assembly facility showed a predominance of Firmicutes. Our study presents the first extended molecular survey and comparison of NASA spacecraft assembly facilities, and provides new insights into the bacterial diversity of clean room environments . [source] Influence of Inorganic Substrata Size, Leaf Litter and Woody Debris Removal on Benthic Invertebrates Resistance to Floods in Two Contrasting Headwater StreamsINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 1 2005J. Bosco Imbert Abstract We studied the influence of inorganic substrata size, leaf litter and woody debris removal on the resistance of benthic invertebrates to floods in two contrasting forested headwater streams of the Agüera basin (northern Spain): Cuchillo stream (stream bed dominated by cobbles and pebbles) and Salderrey stream (stream bed dominated by bedrock and boulders). Generally, floods had a greater effect on benthic invertebrates resistance in the Salderrey stream, apparently due to the high presence of loose substrata overlaying bedrock and the higher scouring of sediment in this stream. Unlike Salderrey stream total number of individuals of Simuliidae, Echinogammarus tarragonensis and Protonemura spp. in riffles greatly increased at the reach scale in the Cuchillo stream after two floods, suggesting that Cuchillo was more retentive than Salderrey. A positive relationship between substrata size and invertebrate resistance to floods was found in the Cuchillo stream but not in the Salderrey stream. It appears that the flood disturbances in the Salderrey stream were too strong to find an increase in resistance as substrata size increased. Invertebrate resistance on leaf litter and resistance predictability were also higher in the Cuchillo stream; the former result suggests that retention of leaf packs was greater in the Cuchillo stream. The lack of a statistically significant effect of woody debris removal may imply that the composition and stability of inorganic substrata have more influence on invertebrate resistance to floods than woody debris at the reach scale in these headwater streams dominated by relatively stable substrata. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Towards waste minimisation in WWTP: activated carbon from biological sludge and its application in liquid phase adsorptionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2002Maria J Martin Abstract Surplus sludge produced during the biological treatment of wastewater requires costly disposal procedures. With increasing environmental and legislative constraints, increasing sludge production and more limited disposal options, new recycling alternatives have to be found. The possibility of obtaining activated carbons from surplus biological sludge by chemical activation with H2SO4 has been investigated. Operational parameters such as the amount of H2SO4 added, the temperature, and activation time were modified to ascertain their influence on the quality of the activated carbon obtained. The quality of the sludge-based activated carbons was evaluated by established characterisation parameters for adsorption from solution such as phenol value, iodine number, methylene blue number and tannin value and compared with commercial activated carbons. Activation at 700,°C for 30,min in the presence of 0.5,cm3 H2SO4,g,1 dry solids in the sludge led to an activated carbon with a good capacity for iodine and tannic acid. The sludge-derived activated carbon obtained is mesoporous in nature with a high presence of large macropores. Weak and moderate acidic surface functional groups were detected on the surface, which impart a hydrophilic nature to the solid. When compared with a commercial activated carbon, the sludge-derived activated carbon performed better when removing dyes with a high presence of anionic solubilising groups and heavy metals. The results indicate that COD adsorption from a biologically-treated effluent may also be an area for application. © 2002 Society of Chemical Industry [source] High-risk HPV presence in cervical specimens after a large loop excision of the cervical transformation zone: Significance of newly detected hr-HPV genotypesJOURNAL OF MEDICAL VIROLOGY, Issue 3 2007Maaike A.P.C. van Ham Abstract Large loop excision of the cervical transformation zone (LLETZ) is a well-established treatment for high-grade cervical intraepithelial neoplasia. It has even been postulated that LLETZ is responsible for the elimination of the infectious agent, human papillomavirus (HPV), causing the lesion. Most studies on HPV detection after LLETZ have focused on the persistence of high-risk (hr-) HPV to identify women at risk for residual or recurrent disease. Therefore, the appearance and significance of hr-HPV types newly detected after surgical treatment has not been studied extensively so far. The presence of hr-HPV in 85 high-grade squamous cervical LLETZ biopsies and in the first follow-up smear was determined. In 80 (94%) of the LLETZ biopsies hr-HPV was detected in contrast to 30 (35%) hr-HPV positive follow-up scrapes. Twenty of the 80 hr-HPV positive women (25%) had the same hr-HPV genotypes in their follow-up cervical smears as was found in the corresponding biopsies. In the follow-up smear of 13 women a new hr-HPV genotype was detected and HPV 18 was newly detected in 8 of them. The remarkably high presence of newly detected HPV 18 genotypes may argue for a release or re-activation of this virus from proximal layers of the cervical canal incised during surgery. J. Med. Virol. 79:314,319, 2007. © 2007 Wiley-Liss, Inc. [source] The influence of artificial aging on the microstructure, mechanical properties, corrosion, and environmental cracking susceptibility of a 7075 friction-stir-weldMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 10 2007C. S. Paglia The influence of overaging to the T7451 temper on the microstructure, the mechanical properties, and the corrosion susceptibility of friction-stir-welded 7075 aluminum alloy was investigated by means of transmission electron microscope (TEM), SEM investigations, constant extension rate tests (CERT), alternate immersion tests, and potentiodynamic scans. The overaging that occurs during welding within the heat-affected zones of the friction-stir-welded 7075-O tempered plates promotes a slight formation of intragranular and grain boundary precipitates and increases the mechanical as well as the corrosion resistance properties as compared to the T7451 welded plates. The "double" overaging treatment, consisting of the T7451 temper and the thermal transient experienced by the heat-affected zones of the 7075-T7451 welded plates, increases the size of the intragranular and the grain boundary precipitates as well as the precipitate-free zones. These facts decrease the mechanical and corrosion properties of the 7075-T7451 weld. The T7451 thermal treatment applied after the welding of the 7075-O plates promotes the high presence of small precipitates and reduces the size of the precipitate-free zones. This fact increases the general corrosion resistance, but decreases the mechanical properties. Therefore, the corrosion as well as the mechanical properties are greatly correlated with minute changes in the microstructure, which can arise by short-term heat exposure as for instance during welding. It was also found that the environmental susceptibility measured by means of CERTs may be influenced by "solution-strengthening" corrosion mechanisms which increase the strain. This fact is present in weld microzones particularly susceptible to corrosion. [source] Ichthyosis vulgaris: novel FLG mutations in the German population and high presence of CD1a+ cells in the epidermis of the atopic subgroupBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2009V. Oji Summary Background, Ichthyosis vulgaris (IV) is a genetic disorder with a prevalence of 1 : 250,1000 caused by filaggrin (FLG) mutations, which also predispose to atopic diseases. Objectives, To study the genotype/phenotype relationship in IV and to analyse whether the suggested skin barrier defect is associated with differences of epidermal dendritic cells. Patients/methods, We evaluated a cohort of 26 German patients with IV, established an IV severity score and analysed epidermal ultrastructure, histology, filaggrin and CD1a antigens. Mutations were screened by restriction enzyme analysis. Particular sequencing techniques allowed the complete FLG analysis to reveal novel mutations. Results, The combined null allele frequency of R501X and 2282del4 was 67·3%. Patients also showed the mutations S3247X and R2447X as well as five novel FLG mutations: 424del17 and 621del4 (profilaggrin S100 domain), 2974delGA (repeat 2), R3766X (repeat 101) and E4265X (repeat 102). Their combined allele frequency in controls was < 0·7%. No mutation was found in one IV patient, all in all ,27% were heterozygous, and the majority (,69%) showed two null alleles. The IV severity score and ultrastructure showed a significant correlation with genotypes. Interestingly, CD1a cell counts showed a significant difference between nonatopic and atopic IV patients both with eczema and without eczema. Conclusions, We confirm that the mutations R501X and 2282del4 represent the most frequent genetic cause in German IV patients. The novel mutations are probably population and family specific. The observed differences of CD1a cells support the hypothesis that there is a barrier defect that predisposes to atopic manifestations, possibly independent of atopic eczema. 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