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Katarzyna Dworaczek Maria Kurzylewska Magdalena Laban Dominika Drzewiecka Agnieszka Pkala-Safiska Anna Turska-Szewczuk 《International journal of molecular sciences》2021,22(8)
In the present work, we performed immunochemical studies of LPS, especially the O-specific polysaccharide (O-PS) of Aeromonas veronii bv. sobria strain K133, which was isolated from the kidney of carp (Cyprinus carpio L.) during an outbreak of motile aeromonad infection/motile aeromonad septicemia (MAI/MAS) on a Polish fish farm. The structural characterization of the O-PS, which was obtained by mild acid degradation of the LPS, was performed with chemical methods, MALDI-TOF mass spectrometry, and 1H and 13C NMR spectroscopy. It was revealed that the O-PS has a unique composition of a linear tetrasaccharide repeating unit and contains a rarely occurring sugar 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine), which may determine the specificity of the serogroup. Western blotting and ELISA confirmed that A. veronii bv. sobria strain K133 belongs to the new serogroup PGO1, which is one of the most commonly represented immunotypes among carp and trout isolates of Aeromonas sp. in Polish aquacultures. Considering the increase in the MAI/MAS incidences and their impact on freshwater species, also with economic importance, and in the absence of an effective immunoprophylaxis, studies of the Aeromonas O-antigens are relevant in the light of epidemiological data and monitoring emergent pathogens representing unknown antigenic variants and serotypes. 相似文献
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Steve Whittaker Simon Tucker Kumutha Swampillai Rachel Laban 《Personal and Ubiquitous Computing》2008,12(3):197-221
Although many recent systems have been built to support Information Capture and Retrieval (ICR), these have not generally
been successful. This paper presents studies that evaluate two different hypotheses for this failure, firstly that systems
fail to address user needs and secondly that they provide only rudimentary support for ICR. Having first presented a taxonomy
of different systems built to support ICR, we then describe a study that attempts to identify user needs for ICR. On the basis
of that study we carried out two user-oriented evaluations. In the first, we carried out a task-based evaluation of a state-of-the-art
ICR system, finding that it failed to provide users with abstract ways to view meetings data, and did not present users with
information categories that they considered to be important. In a second study, we introduce a new method for comparative
evaluation of different techniques for accessing meetings data. The second study showed that simple interface techniques that
extracted key information from meetings were effective in allowing users to extract gist from meetings data. We conclude with
a discussion of outstanding issues and future directions for ICR research. 相似文献
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Bergmann FD Abu Laban NM Meyer AH Elsner M Meckenstock RU 《Environmental science & technology》2011,45(16):6947-6953
Anaerobic polycyclic aromatic hydrocarbon (PAH) degradation is a key process for natural attenuation of oil spills and contaminated aquifers. Assessments by stable isotope fractionation, however, have largely been limited to monoaromatic hydrocarbons. Here, we report on measured hydrogen isotope fractionation during strictly anaerobic degradation of the PAH naphthalene. Remarkable large hydrogen isotopic enrichment factors contrasted with much smaller values for carbon: ε(H) = -100‰ ± 15‰, ε(C) = -5.0‰ ± 1.0‰ (enrichment culture N47); ε(H) = -73‰ ± 11‰, ε(C) = -0.7‰ ± 0.3‰ (pure culture NaphS2). This reveals a considerable potential of hydrogen isotope analysis to assess anaerobic degradation of PAHs. Furthermore, we investigated the conclusiveness of dual isotope fractionation to characterize anaerobic aromatics degradation. C and H isotope fractionation during benzene degradation (ε(C) = -2.5‰ ± 0.2‰; ε(H) = -55‰ ± 4‰ (sulfate-reducing strain BPL); ε(C) = -3.0‰ ± 0.5‰; ε(H) = -56‰ ± 8‰ (iron-reducing strain BF)) resulted in dual isotope slopes (Λ = 20 ± 2; 17 ± 1) similar to those reported for nitrate-reducers. This breaks apart the current picture that anaerobic benzene degradation by facultative anaerobes (denitrifiers) can be distinguished from that of strict anaerobes (sulfate-reducers, fermenters) based on the stable isotope enrichment factors. 相似文献
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Mohammad Abu‐Laban Prakash Hamal Julien H. Arrizabalaga Anoosha Forghani Asela S. Dikkumbura Raju R. Kumal Louis H. Haber Daniel J. Hayes 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(50)
It is becoming more apparent in tissue engineering applications that fine temporal control of multiple therapeutics is desirable to modulate progenitor cell fate and function. Herein, the independent temporal control of the co‐delivery of miR‐148b and miR‐21 mimic plasmonic nanoparticle conjugates to induce osteogenic differentiation of human adipose stem cells (hASCs), in a de novo fashion, is described. By applying a thermally labile retro‐Diels–Alder caging and linkage chemistry, these miRNAs can be triggered to de‐cage serially with discrete control of activation times. The method relies on illumination of the nanoparticles at their resonant wavelengths to generate sufficient local heating and trigger the untethering of the Diels–Alder cycloadduct. Characterization of the photothermal release using fluorophore‐tagged miRNA mimics in vitro is carried out with fluorescence measurements, second harmonic generation, and confocal imaging. Osteogenesis of hASCs from the sequential co‐delivery of miR‐21 and miR‐148b mimics is assessed using xylenol orange and alizarin red staining of deposited minerals, and quantitative polymerase chain reaction for gene expression of osteogenic markers. The results demonstrate that sequential miRNA mimic activation results in upregulation of osteogenic markers and mineralization relative to miR‐148b alone, and co‐activation of miR‐148b and miR‐21 at the same time. 相似文献
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We present a new technique to measure absolute total collision cross sections from metastable neon atoms. The technique is based on the observation of the decay rate of trapped atoms as they collide with room temperature atoms. We present the first measurement of this kind using trapped neon atoms in the (3)P(2) metastable state colliding with thermal ground state argon. The measured cross section has a value of 556+/-26 A(2). 相似文献
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N. R. Laban 《金属精饰学会汇刊》2013,91(1):149-156
The selection of a pretreatment and conversion coating cycle for any application is subject to many considerations, including anticipated environmental service conditions, life of finished article, type of finish to be applied, condition of metal surface prior to pretreatment, design of article to be treated, throughput required, space and/or equipment available, capital costs, operational and maintenance costs. The characteristics of various types of pretreatments and conversion coatings for ferrous and non ferrous metals are discussed in relationship to the above considerations. It is suggested that the final selection will be on economic grounds from processes of adequate technical merit but subject to any site limitations. 相似文献
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G Asiimwe-Okiror AA Opio J Musinguzi E Madraa G Tembo M Cara?l 《Canadian Metallurgical Quarterly》1997,11(14):1757-1763
OBJECTIVE: To describe sexual behaviour that may partly explain a decline in HIV seroprevalence in pregnant women in urban settings in Uganda, East Africa. SETTINGS: Two major urban districts in Uganda. METHODS: Repeated population-based behavioural surveys in 1989 and 1995, and repeated HIV serological surveys in consecutive pregnant women attending antenatal clinics from 1989 to 1995. RESULTS: During the study period, a 2-year delay in the onset of sexual intercourse among youths aged 15-24 years and a 9% decrease in casual sex in the past year in male youths aged 15-24 years were reported. Men and women reported a 40% and 30% increase in experience of condom use, respectively. In the same study area, over the same period, there was an overall 40% decline in the rates of HIV seroprevalence among pregnant women attending antenatal clinics. It can be hypothesized that the observed declining trends in HIV correspond to a change in sexual behaviour and condom use, especially among youths. CONCLUSIONS: This is the first report of a change over a period of 6 years in male and female sexual behaviour, assessed at the population level, that may partly explain the observed decline in HIV seroprevalence in young pregnant women in urban Uganda. This result should encourage AIDS control programmes to pursue their prevention activities. 相似文献