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31.
Mikelsaar R Nelis M Kurg A Zilina O Korrovits P Rätsep R Väli M 《Journal of applied genetics》2012,53(1):93-97
We describe the first case of two chromosomal abnormalities, balanced reciprocal translocation t(5;13)(q33;q12.1) and a microduplication
in the region 9q31.1, in a man suffering from infertility and pollinosis. In the region 13q12.1 is located the TUBA3C (tubulin, alpha 3c) gene, which plays an important dynamic role in the motility of flagella. This case might support the
opinion that haploinsufficiency of the TUBA3C gene could be the cause of sperm immotility and abnormal sperm morphology, resulting in infertility in the patient. Single-nucleotide
polymorphism (SNP) array analysis revealed a novel 9q31.1 microduplication inherited from both parents, which contributes
to the genomic instability. 相似文献
32.
L Graciano JM Corrêa RF Gandra FA Seixas MK Kadowaki SC Sampaio JL da Conceição Silva CA Osaku Rde C Simão 《World journal of microbiology & biotechnology》2012,28(9):2879-2888
The xynB1 gene (CCNA 01040) of Caulobacter crescentus that encodes a bifunctional enzyme containing the conserved β-Xylosidase and α-L: -Arabinofuranosidase (β-Xyl I-α-L: -Ara) domains was amplified by PCR and cloned into the vector pJet1.2Blunt. The xynB1 gene was subcloned into the vector pPROEX-hta that produces a histidine-fused translation product. The overexpression of recombinant β-Xyl I-α-L: -Ara was induced with IPTG in BL21 (DE3) and the resulting intracellular protein was purified with pre-packaged nickel-Sepharose columns. The recombinant β-Xyl I-α-L: -Ara exhibited a specific β-Xylosidase I activity of 1.25?U?mg(-1) to oNPX and a specific α-L: -Arabinofuranosidase activity of 0.47?U?mg(-1) to pNPA. The predominant activity of the recombinant enzyme was its β-Xylosidase I activity, and the enzymatic characterization was focused on it. The β-Xylosidase I activity was high over the pH range 3-10, with maximal activity at pH 6. The enzyme activity was optimal at 45?°C, and a high degree of stability was verified over 240?min at this temperature. Moreover, β-Xylosidase activity was inhibited in the presence of the metals Zn(2+) and Cu(2+), and the enzyme exhibited K(M) and V(Max) values of 2.89?±?0.13?mM and 1.4?±?0.04?μM?min(-1) to oNPX, respectively. The modeled structure of β-xylosidase I showed that its active site is highly conserved compared with other structures of the GH43 family. The increase in the number of contact residues responsible for maintaining the dimeric structure indicates that this dimer is more stable than the tetramer form. 相似文献
33.
Fourier Transform Infrared Radiation (FTIR) spectroscopy is one of the most powerful methods for the detection of gaseous constituents, aerosols, and dust in planetary atmospheres. Infrared spectroscopy plays an important role in searching for biomarkers, organics and biological substances in the Universe. The possibility of detection and identifications with FTIR spectrometer of bio-aerosol spores (Bacillus atrophaeus var. globigii=BG) in the atmosphere is discussed in this paper. We describe the results of initial spectral measurements performed in the laboratory and in the field. The purpose of these experiments was to detect and to identify bio-aerosol spores in two conditions: 1) In a closed chamber where the thermal contrast between the background and aerosols was large, and 2) In open air where the thermal contrast between the background and aerosols was small. The extinction spectrum of BG spores was deduced by comparing our measurements with models, and other measurements known from the literature. Our theoretical and experimental studies indicate that, during passive remote sensing measurements, it is difficult-but possible to detect and to identify bio-aerosol clouds by their spectral signatures. The simple spectral analysis described in the paper can be useful for the detection of various kinds of trace aerosols-not only in the Earth's atmosphere, but also during planetary missions in the environments of other astronomical objects such as planets, comets etc. We expect that the interpretation of data from spectrometric sounding of Venus and Mars during the current missions Mars and Venus Express, and later during the Rosetta mission will benefit from our experimental work and numerical modelling. 相似文献
34.
Nosratollah?Ale-Agha Adrien?Bolay Uwe?BraunEmail author Benno?Feige Horst?Jage Volker?Kummer Ale??Lebeda Marcin?Pi?tek Hyeon-Dong?Shin Katarína?Zimmermannová-Pastir?aková 《Mycological Progress》2004,3(4):291-296
The recent epidemic spread of the North American powdery mildew Erysiphe elevata in Europe is described and discussed. Since 2002, this plant pathogenic fungus has been collected on Catalpa bignonioides, C. erubescens and C. speciosa in the Czech Republic, Germany, Hungary, Slovakia and Switzerland. The diagnostically important anamorph of E. elevata, so far unknown, is described and illustrated in detail. Type material of Erysiphe catalpae and two specimens of E. catalpae recently collected in Poland have been examined and compared with E. elevata. The anamorph as well as the teleomorph of E. catalpae proved to be easily distinguishable from E. elevata. The supposition that E. catalpae, introduced in Armenia, was based on immature ascomata of E. elevata proved to be wrong. The origin and distribution of E. catalpae are discussed, and a key to powdery mildew fungi on Catalpa spp. in Europe is provided. 相似文献
35.
36.
Ivan?Mu?ozEmail author Joan?Rieradevall Xavier?Doménech Lloren??Milà 《The International Journal of Life Cycle Assessment》2004,9(4):272-280
Goal, Scope and Background Gipuzkoa is a department of the Vasque Country (Spain) with a population of about 700,000 people. By the year 2000 approximately
85% of municipal solid waste in this area was managed by landfilling, and only 15% was recycled. Due to environmental law
restrictions and landfill capacity being on its limit, a planning process was initiated by the authorities. LCA was used,
from an environmental point of view, to assess 7 possible scenarios arising from the draft Plan for the 2016 time horizon.
Main Features In each scenario, 9 waste flows are analysed: rest waste, paper and cardboard, glass containers, light packaging, organic-green
waste, as well as industrial/commercial wood, metals and plastics, and wastewater sludge. Waste treatments range from recycling
to energy recovery and landfilling.
Results Recycling of the waste flows separated at the source (paper and cardboard, glass, light packaging, organic-green waste, wood
packaging, metals and plastics) results in net environmental benefits caused by the substitution of primary materials, except
in water consumption. These benefits are common to the 7 different scenarios analysed. However, some inefficiencies are detected,
mainly the energy consumption in collection and transport of low density materials, and water consumption in plastic recycling.
The remaining flows, mixed waste and wastewater sludge, are the ones causing the major environmental impacts, by means of
incineration, landfilling of partially stabilised organic material, as well as thermal drying of sludge. With the characterisation
results, none of the seven scenarios can be clearly identified as the most preferable, although, due to the high recycling
rates expected by the Plan, net environmental benefits are achieved in 9 out of 10 impact categories in all scenarios when
integrated waste management is assessed (the sum of the 9 flows of waste). Finally, there are no relevant differences between
scenarios concerning the number of treatment plants considered. Nevertheless, only the effects on transportation impacts were
assessed in the LCA, since the plant construction stage was excluded from the system boundaries.
Conclusions The results of the study show the environmental importance of material recycling in waste management, although the recycling
schemes assessed can be improved in some aspects. It is also important to highlight the environmental impact of incineration
and landfilling of waste, as well as thermal drying of sludge using fossil fuels. One of the main findings of applying LCA
to integrated waste management in Gipuzkoa is the fact that the benefits of high recycling rates can compensate for the impacts
of mixed waste and wastewater sludge.
Recommendations and Outlook Although none of the scenarios can be clearly identified as the one having the best environmental performance, the authorities
in Gipuzkoa now have objective information about the future scenarios, and a multidisciplinary panel could be formed in order
to weight the impacts if necessary. In our opinion, LCA was successfully applied in Gipuzkoa as an environmental tool for
decision making. 相似文献
37.
Rastislav?Varha? Marián?AntalíkEmail author Mikulá??Bánó 《Journal of biological inorganic chemistry》2004,9(1):12-22
Thermally denatured horse heart ferrocytochrome c (ferrocyt c) has been characterized using absorption spectroscopy, differential scanning calorimetry (DSC) and viscometry at pH 7.0. DSC experiments have yielded the transition temperature of denaturant-free ferrocyt c unfolding as 100.6±0.3 °C, indicating an extremely high stability of the protein. The presence of guanidine hydrochloride (GdnHCl) facilitated estimation of the structural features of thermally unfolded ferrocyt c. The stability of the protein, expressed by G
D at 25 °C, is 59±5 kJ mol–1 (DSC) and 65±6 kJ mol–1 (absorption spectroscopy). An absorption spectrum of ferrocyt c demonstrates that the heme occurs in the high-spin state at extreme denaturing conditions (94 °C, 6.6 M GdnHCl). Absorption spectroscopy, using heme as a probe, shows that thermal denaturation of ferrocyt c occurs as a transition from a native low-spin (Met80/His18) to a high-spin disordered state with involvement of non-native, low-spin (bis-His) species.Abbreviations CD
circular dichroism
- cyt c
cytochrome c
- DSC
differential scanning calorimetry
- ferricyt c
ferricytochrome c
- ferrocyt c
ferrocytochrome c
- GdnHCl
guanidine hydrochloride
- NHE
normal hydrogen electrode 相似文献
38.
Anita?Kuras Ma?gorzata?Korbin Edward??urawiczEmail author 《Plant Cell, Tissue and Organ Culture》2004,79(2):189-193
Two PCR-based techniques, RAPD and ISSR, were utilized for determination of genetic relationship of 24 strawberry cultivars used in breeding program at the Research Institute of Pomology and Floriculture in Poland. Polymorphism of investigated genotypes was observed in reactions with 23 out of 48 tested RAPD primes and 41 from 90 tested ISSR primers. Relationship, determined on the base of polymorphic products analysis and showed in the form of dendrograms (UPGMA percent method), was generally similar for both techniques, although similarity values based on ISSR data were higher than those based on RAPD. The parallel use of two data sets seems to allow for precise estimation of cultivars relationship and diminishing mistakes connected with methods' technical limitations. 相似文献
39.
Sectional taxonomy ofTaraxacum in steppe or subsaline habitats in Central Asia is revised based on material collected during expeditions, cultivated or
studied in herbarium. Two new sections are described from that area:T. sect.Stenoloba similar toT. sect.Leucantha (syn.:T. sect.Sinensia), andT. sect.Suavia allied toT. sect.Dissecta. The type species of the sectionSuavia is described asTaraxacum formosissimum
Kirschner etŠtěpánek. Widespread mountain dandelions of the Caucasus, intermediate between the sect.Piesis andT. stevenii, are described asT. sect.Confusa. Taraxacum species dominating dry habitats in S Ukraine and Crimea are described asT. sect.Borysthenica. Species belonging to the new sections were found to be polyploid and agamospermous. 相似文献
40.
Izabela?Andrzejewska Pawe??T.?Dolata Leszek?Jerzak Jerzy?Ptaszyk Piotr?TryjanowskiEmail author Piotr?Zduniak 《European Journal of Wildlife Research》2004,50(4):218-220
In 2002 and 2003, blood samples from white stork (Ciconia ciconia) chicks were examined for the presence of antibodies against Listeria monocytogenes. Listeria antibodies were detected in 121 (59%) of 205 chick samples. The probability of Listeria antibodies being present increased with chick age; chicks detected with Listeria antibodies were in better condition than those without the bacterium. 相似文献