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141.
142.
The use of membrane sequencing batch reactors, operated at HRT of 8, 16 and 24 h, was considered for the treatment of a synthetic petroleum wastewater. Increase in HRT resulted in statistically significant decrease in MLSS. Removal efficiencies higher than 97% were found for the three model hydrocarbon pollutants at all HRTs, with air stripping making a small contribution to overall removal. Particle size distribution (PSD) and microscopic analysis showed reduction in the protozoan populations in the activated sludge with decreasing HRT. PSD analysis also showed a higher proportion of larger and smaller sized particles at the lowest HRT. The rate of membrane fouling was found to increase with decreasing HRT; SMP, especially carbohydrate SMP, and mixed liquor apparent viscosity also showed a pronounced increase with decreasing HRT, whereas the concentration of EPS and its components decreased. FTIR analysis identified organic compounds as the main component of membrane pore fouling. 相似文献
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144.
Toward nanoscale genome sequencing 总被引:2,自引:0,他引:2
This article reports on the state-of-the-art technologies that sequence DNA using miniaturized devices. The article considers the miniaturization of existing technologies for sequencing DNA and the opportunities for cost reduction that 'on-chip' devices can deliver. The ability to construct nano-scale structures and perform measurements using novel nano-scale effects has provided new opportunities to identify nucleotides directly using physical, and not chemical, methods. The challenges that these technologies need to overcome to provide a US$1000-genome sequencing technology are also presented. 相似文献
145.
<Emphasis Type="Italic">Arabidopsis rd29A::DREB1A</Emphasis> enhances freezing tolerance in transgenic potato 总被引:2,自引:0,他引:2
Behnam B Kikuchi A Celebi-Toprak F Kasuga M Yamaguchi-Shinozaki K Watanabe KN 《Plant cell reports》2007,26(8):1275-1282
The freezing tolerance of 38 independent transgenic potato lines derived from the cultivar Desiree was tested in vitro using
plantlets. The lines were transgenic for the DREB1A gene under control of the rd29A promoter, both of which were derived from Arabidopsis thaliana. The level of damage caused by freezing varied significantly among the transgenic clones and a non-transgenic control (cv.
Desiree). Phenotypic evaluation indicated that the variable responses to freezing were attributable to genotypic variation,
but freezing tolerance was not dependent on the number of insertions. Northern blot analysis using a DREB1A cDNA probe revealed high levels of DREB1A expression among the transgenic clones during the initial cold exposure at 4°C (after 2 h) and in the early stages of freezing
(−20°C, 1–10 min). Furthermore, a linear correlation was detected between the level of expression and the phenotypic response
for all lines except D138. Thus, in the case of potato, a significant increase in freezing tolerance was observed in vitro
on a small scale following the introduction of rd29A::DREB1A. Additional testing will show whether this strategy can be used for tolerance breeding in potato and to increase the freezing
tolerance of other agriculturally important crops.
Babak Behnam and Akira Kikuchi equally contributed for this work. 相似文献
146.
Systematic optimization of a lectin-based enzyme-linked immunosorbent assay (ELISA) procedure using a panel of 21 biotinylated plant lectins and a glycoprotein with defined glycosylation (i) identified blocking as a limiting step in solid phase sugar binding analysis and (ii) found Synblock to be a better alternative to bovine serum albumin (BSA) as blocking agent. 相似文献
147.
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149.
Morteza Moghaddasian Hamidreza Arab Ezzat Dadkhah Hamidreza Boostani Azam Rezaei Babak Mohammad Reza Abbaszadegan 《Gene》2014
Background
Papillon–Lefèvre syndrome (PLS) is a rare autosomal recessive disorder characterized by hyperkeratosis involving the palms, soles, elbows, and knees followed by periodontitis, destruction of alveolar bone, and loss of primary and permanent teeth. Mutations of the lysosomal protease cathepsin C gene (CTSC) have been shown to be the genetic cause of PLS. This study analyzed CTSC mutations in five Iranian families with PLS and modeled the protein for mutations found in two of them.Methods
DNA analysis was performed by direct automated sequencing of genomic DNA amplified from exonic regions and associated splice intron site junctions of CTSC. RFLP analyses were performed to investigate the presence of previously unidentified mutation(s) in control groups. Protein homology modeling of the deduced novel mutations (P35 delL and R272P) was performed using the online Swiss-Prot server for automated modeling and analyzed and tested with special bioinformatics tools to better understand the structural effects caused by mutations in cathepsin C protein (CTSC).Results
Six Iranian patients with PLS experienced premature tooth loss and palm plantar hyperkeratosis. Sequence analysis of CTSC revealed a novel mutation (P35delL) in exon 1 of Patient 1, and four previously reported mutations; R210X in Patient 2, R272P in Patient 3, Q312R in two siblings of family 4 (Patients 4 and 5), and CS043636 in Patient 6. RFLP analyses revealed different restriction fragment patterns between 50 healthy controls and patients for the P35delL mutation. Modeling of the mutations found in CTSC, P35delL in Patient 1 and R272P in Patient 3 revealed structural effects, which caused the functional abnormalities of the mutated proteins.Conclusions
The presence of this mutation in these patients provides evidence for founder CTSC mutations in PLS. This newly identified P35delL mutation leads to the loss of a leucine residue in the protein. The result of this study indicates that the phenotypes observed in these two patients are likely due to CTSC mutations. Also, structural analyses of the altered proteins identified changes in energy and stereochemistry that likely alter protein function. 相似文献150.
Babak Zahiri Yaghoub Fathipour Mohammad Khanjani Saeid Moharramipour Myron Philip Zalucki 《Population Ecology》2014,56(1):185-194
Key factors are those causes that are most responsible for the observed changes in population density between generations. Stage-frequency of alfalfa weevil was modeled using Manly-1997 model. Multiple decrement life table parameters from an 8 year-field study were analyzed using traditional and λ contribution methods. In traditional method, the key factor was determined as k LII, the death of period-two larvae from all mortality factors, whereas in λ contribution method, the key factor was determined as b 2&3, oviposition rate of females per square meter. These differences result directly from the sensitivity of the population growth rate, λ, to variation of both k and b in various stages of the weevil. Among all mortality factors, only k LI-Z, the death of period-one larvae from the entomopathogenic fungus, Zoophthora phytonomi (Arthur) Batko (Zygomycetes: Entomophthoraceae), k LII and k LII-Z, the death of period-two larvae from Z. phytonomi, acted in a density dependent fashion. Remaining factors were independent of population densities affected. Using λ contribution method, life table approach still remains a major way of studying the dynamics of field populations for applied ecologists and population managers. 相似文献