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Sample records for raimo klli aldis

  1. Surface contribution to high-order aberrations using the Aldis therem and Andersen's algorithms

    NASA Astrophysics Data System (ADS)

    Ortiz-Estardante, A.; Cornejo-Rodriguez, Alejandro

    1990-07-01

    Formulae and computer programs were developed for surface contributions to high order aberrations coefficients using the Aldis theorem and Andersen algor ithms for a symmetr ical optical system. 2. THEORY Using the algorithms developed by T. B. Andersent which allow to calculate the high order aberrations coefficients of an optical system. We were able to obtain a set of equations for the contributions of each surface of a centered optical system to such aberration coefficiets by using the equations of Andersen and the so called Aldis theorem 3. COMPUTER PROGRAMS AND EXAMPLES. The study for the case of an object at infinite has been completed and more recently the object to finite distance case has been also finished . The equations have been properly programed for the two above mentioned situations . Some typical designs of optical systems will be presented and some advantages and disadvantages of the developed formulae and method will be discussed. 4. CONCLUSIONS The algorithm developed by Anderson has a compact notation and structure which is suitable for computers. Using those results obtained by Anderson together with the Aldis theorem a set of equations were derived and programmed for the surface contributions of a centered optical system to high order aberrations. 5. REFERENCES 1. T . B. Andersen App 1. Opt. 3800 (1980) 2. A. Cox A system of Optical Design Focal Press 1964 18 / SPIE

  2. Black phosphorus-assisted laser desorption ionization mass spectrometry for the determination of low-molecular-weight compounds in biofluids.

    PubMed

    He, Xiao-Mei; Ding, Jun; Yu, Lei; Hussain, Dilshad; Feng, Yu-Qi

    2016-09-01

    Quantitative analysis of small molecules by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been a challenging task due to matrix-derived interferences in low m/z region and poor reproducibility of MS signal response. In this study, we developed an approach by applying black phosphorus (BP) as a matrix-assisted laser desorption ionization (MALDI) matrix for the quantitative analysis of small molecules for the first time. Black phosphorus-assisted laser desorption/ionization mass spectrometry (BP/ALDI-MS) showed clear background and exhibited superior detection sensitivity toward quaternary ammonium compounds compared to carbon-based materials. By combining stable isotope labeling (SIL) strategy with BP/ALDI-MS (SIL-BP/ALDI-MS), a variety of analytes labeled with quaternary ammonium group were sensitively detected. Moreover, the isotope-labeled forms of analytes also served as internal standards, which broadened the analyte coverage of BP/ALDI-MS and improved the reproducibility of MS signals. Based on these advantages, a reliable method for quantitative analysis of aldehydes from complex biological samples (saliva, urine, and serum) was successfully established. Good linearities were obtained for five aldehydes in the range of 0.1-20.0 μM with correlation coefficients (R (2)) larger than 0.9928. The LODs were found to be 20 to 100 nM. Reproducibility of the method was obtained with intra-day and inter-day relative standard deviations (RSDs) less than 10.4 %, and the recoveries in saliva samples ranged from 91.4 to 117.1 %. Taken together, the proposed SIL-BP/ALDI-MS strategy has proved to be a reliable tool for quantitative analysis of aldehydes from complex samples. Graphical Abstract An approach for the determination of small molecules was developed by using black phosphorus (BP) as a matrix-assisted laser desorption ionization (MALDI) matrix. PMID:27382971

  3. Bile pigments: newcomers to the cell signaling arena.

    PubMed

    Maines, Mahin D

    2003-01-01

    The article highlighted in this issue is "2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-Induced Accumulation of Biliverdin and Hepatic Peliosis in Rats," by Marjo Nittynen, Jouni T. Tuomisto, Seppo Auriola, Raimo Pohjanvirta, Paula Syrjälä, Ulla Simanainen, Matti Viluksela, and Jouko Tuomisto (pp. 112-123). PMID:12520070

  4. Proceedings of the Conference of the International Group for the Psychology of Mathematics Education (31st, Seoul, Korea, July 8-13, 2007). Volume 3

    ERIC Educational Resources Information Center

    Woo, Jeong-Ho, Ed.; Lew, Hee-Chan, Ed.; Park, Kyo-Sik Park, Ed.; Seo, Dong-Yeop, Ed.

    2007-01-01

    This third volume of the 31st annual proceedings of the International Group for the Psychology of Mathematics Education conference presents research reports for author surnames beginning Han- through Miy-. Reports include: (1) Elementary Education Students' Memories of Mathematics in Family Context (Markku S. Hannula, Raimo Kaasila, Erkki…

  5. High order surface aberration contributions from phase space analysis of differential rays.

    PubMed

    Chen, Bo; Herkommer, Alois M

    2016-03-21

    Phase space methods are very popular for illumination systems or paraxial system analysis. In this paper it will be shown that it is also a promising tool to visualize and quantify surface aberration contributions, including all orders. The method is based on the calculation and propagation of a differential ray pair. In order to validate the method we compare to Aldis calculus, an exact method to determine high order aberrations in rotational symmetric systems. A triplet lens is used as an example to visualize the results. The analysis indicates that the phase space method is a very good approximation to Aldis calculus and moreover it is not limited to any symmetry assumptions. PMID:27136789

  6. Preparation of nanofluids using laser ablation in liquid technique

    SciTech Connect

    Tran, P.X.; Soong, Yee

    2007-06-01

    In this work we report some results on thermal and transport properties of Ag-di water and Al-di water nanofluids that were prepared using Nd:yag laser to ablate Ag and Al in deionized water. The produced nanofluids were characterized using UV-VIS spectroscopy and TEM analysis. Our results on the UV-VIS spectra of the generated nanofluids demonstrated that using laser ablation in liquid we could generate stable colloids containing well-dispersed nanosized particles without use of any dispersants or surface reactive reagents. For Ag-di water nanofluids, the particles were spherical and the majority of the particles were in the 9 – 21 nm range with some big ones 23 - 26nm in size. The results on Al showed that the amplitude of the UV-VIS absorption spectra of Al-di water changed with time indicating that the ablated Al species reacts with water to yield an amorphous gel that transforms to the crystallized aluminum hydroxides with different shapes and sizes. The shapes were fibrous, triangular, rectangular, spherical shapes and joining of two pieces of triangles. In fact, these triangular and rectangular shapes were indeed pyramidal structures and hexagonal prisms, respectively.

  7. Multilocus Sequence Typing Confirms the Close Genetic Interrelatedness of Three Distinct Flavescence Dorée Phytoplasma Strain Clusters and Group 16SrV Phytoplasmas Infecting Grapevine and Alder in Europe▿

    PubMed Central

    Arnaud, Guillaume; Malembic-Maher, Sylvie; Salar, Pascal; Bonnet, Patrick; Maixner, Michael; Marcone, Carmine; Boudon-Padieu, Elisabeth; Foissac, Xavier

    2007-01-01

    Vineyards of southern France and northern Italy are affected by the flavescence dorée (FD) phytoplasma, a quarantine pathogen transmitted by the leafhopper of Nearctic origin Scaphoideus titanus. To better trace propagation of FD strains and identify possible passage between the vineyard and wild plant compartments, molecular typing of phytoplasma strains was applied. The sequences of the two genetic loci map and uvrB-degV, along with the sequence of the secY gene, were determined among a collection of FD and FD-related phytoplasmas infecting grapevine, alder, elm, blackberry, and Spanish broom in Europe. Sequence comparisons and phylogenetic analyses consistently indicated the existence of three FD phytoplasma strain clusters. Strain cluster FD1 (comprising isolate FD70) displayed low variability and represented 17% of the disease cases in the French vineyard, with a higher incidence of the cases in southwestern France. Strain cluster FD2 (comprising isolates FD92 and FD-D) displayed no variability and was detected both in France (83% of the cases) and in Italy, whereas the more-variable strain cluster FD3 (comprising isolate FD-C) was detected only in Italy. The clonal property of FD2 and its wide distribution are consistent with diffusion through propagation of infected-plant material. German Palatinate grapevine yellows phytoplasmas (PGY) appeared variable and were often related to some of the alder phytoplasmas (AldY) detected in Italy and France. Finally, phylogenetic analyses concluded that FD, PGY, and AldY were members of the same phylogenetic subclade, which may have originated in Europe. PMID:17468266

  8. Genetic diversity of European phytoplasmas of the 16SrV taxonomic group and proposal of 'Candidatus Phytoplasma rubi'.

    PubMed

    Malembic-Maher, Sylvie; Salar, Pascal; Filippin, Luisa; Carle, Patricia; Angelini, Elisa; Foissac, Xavier

    2011-09-01

    In addition to the grapevine flavescence dorée phytoplasmas, other members of taxonomic group 16SrV phytoplasmas infect grapevines, alders and species of the genera Clematis and Rubus in Europe. In order to investigate which phytoplasmas constitute discrete, species-level taxa, several strains were analysed by comparing their 16S rRNA gene sequences and a set of five housekeeping genes. Whereas 16S rRNA gene sequence similarity values were >97.5 %, the proposed threshold to distinguish two 'Candidatus Phytoplasma' taxa, phylogenetic analysis of the combined sequences of the tuf, rplV-rpsC, rplF-rplR, map and uvrB-degV genetic loci showed that two discrete phylogenetic clusters could be clearly distinguished. The first cluster grouped flavescence dorée (FD) phytoplasmas, alder yellows (AldY) phytoplasmas, Clematis (CL) phytoplasmas and the Palatinate grapevine yellows (PGY) phytoplasmas. The second cluster comprised Rubus stunt (RS) phytoplasmas. In addition to the specificity of the insect vector, the Rubus stunt phytoplasma contained specific sequences in the 16S rRNA gene. Hence, the Rubus stunt phytoplasma 16S rRNA gene was sufficiently differentiated to represent a novel putative taxon: 'Candidatus Phytoplasma rubi'. PMID:20889771

  9. Lightning Climatology with a Generalized Additive Model

    NASA Astrophysics Data System (ADS)

    Simon, Thorsten; Mayr, Georg; Umlauf, Nikolaus; Zeileis, Achim

    2016-04-01

    This study present a lightning climatology on a 1km x 1km grid estimated via generalized additive models (GAM). GAMs provide a framework to account for non-linear effects in time and space and for non-linear spatial-temporal interaction terms simultaneously. The degrees of smoothness of the non-linear effects is selected automatically in our approach. Furthermore, the influence of topography is captured in the model by including a non-linear term. To illustrate our approach we use lightning data from the ALDIS networks and selected a region in Southeastern Austria, where complex terrain extends from 200 an 3800 m asl and summertime lightning activity is high compared to other parts of the Eastern Alps. The temporal effect in the GAM shows a rapid increase in lightning activity in early July and a slow decay in activity afterwards. The estimated spatial effect is not very smooth and requires approximately 225 effective degrees of freedom. It reveals that lightning is more likely in the Eastern and Southern part of the region of interest. This spatial effect only accounts for variability not already explained by the topography. The topography effect shows lightning to be more likely at higher altitudes. The effect describing the spatio-temporal interactions takes approximately 200 degrees of freedom, and reveals local deviations of the climatology.

  10. Contrasting controls on the phosphorus concentration of suspended particulate matter under baseflow and storm event conditions in agricultural headwater streams.

    PubMed

    Cooper, Richard J; Rawlins, Barry G; Krueger, Tobias; Lézé, Bertrand; Hiscock, Kevin M; Pedentchouk, Nikolai

    2015-11-15

    Whilst the processes involved in the cycling of dissolved phosphorus (P) in rivers have been extensively studied, less is known about the mechanisms controlling particulate P concentrations during small and large flows. This deficiency is addressed through an analysis of large numbers of suspended particulate matter (SPM) samples collected under baseflow (n=222) and storm event (n=721) conditions over a 23-month period across three agricultural headwater catchments of the River Wensum, UK. Relationships between clay mineral and metal oxyhydroxide associated elements were assessed and multiple linear regression models for the prediction of SPM P concentration under baseflow and storm event conditions were formulated. These models, which explained 71-96% of the variation in SPM P concentration, revealed a pronounced shift in P association from iron (Fe) dominated during baseflow conditions to particulate organic carbon (POC) dominated during storm events. It is hypothesised this pronounced transition in P control mechanism, which is consistent across the three study catchments, is driven by changes in SPM source area under differing hydrological conditions. In particular, changes in SPM Fe-P ratios between small and large flows suggest there are three distinct sources of SPM Fe; surface soils, subsurface sediments and streambed iron sulphide. Further examination of weekly baseflow data also revealed seasonality in the Fe-P and aluminium oxalate-dithionate (Alox-Aldi) ratios of SPM, indicating temporal variability in sediment P sorption capacity. The results presented here significantly enhance our understanding of SPM P associations with soil derived organic and inorganic fractions under different flow regimes and has implications for the mitigation of P originating from different sources in agricultural catchments. PMID:26150307

  11. Strategies to fight low-cost rivals.

    PubMed

    Kumar, Nirmalya

    2006-12-01

    Companies find it challenging and yet strangely reassuring to take on opponents whose strategies, strengths, and weaknesses resemble their own. Their obsession with familiar rivals, however, has blinded them to threats from disruptive, low-cost competitors. Successful price warriors, such as the German retailer Aldi, are changing the nature of competition by employing several tactics: focusing on just one or a few consumer segments, delivering the basic product or providing one benefit better than rivals do, and backing low prices with superefficient operations. Ignoring cutprice rivals is a mistake because they eventually force companies to vacate entire market segments. Price wars are not the answer, either: Slashing prices usually lowers profits for incumbents without driving the low-cost entrants out of business. Companies take various approaches to competing against cut-price players. Some differentiate their products--a strategy that works only in certain circumstances. Others launch low-cost businesses of their own, as many airlines did in the 1990s--a so-called dual strategy that succeeds only if companies can generate synergies between the existing businesses and the new ventures, as the financial service providers HSBC and ING did. Without synergies, corporations are better off trying to transform themselves into low-cost players, a difficult feat that Ryanair accomplished in the 1990s, or into solution providers. There will always be room for both low-cost and value-added players. How much room each will have depends not only on the industry and customers' preferences, but also on the strategies traditional businesses deploy. PMID:17183797

  12. An Observational Study on Aberrant Methylation of Runx3 With the Prognosis in Chronic Atrophic Gastritis Patients.

    PubMed

    Zhao, Chunna; Li, Ping; Zhang, Lili; Wang, Bei; Xiao, Lili; Guo, Feng; Wei, Yueguang

    2016-05-01

    The aim of this study is to discuss whether the methylation levels of Runx3 could be used as the early biomarker for predicting the prognosis in chronic atrophic gastritis (CAG) patients. A total of 200 subjects including 60 controls without CAG (Group 1), 70 patients with mild CAG (Group 2), and 70 patients with moderate and severe CAG (Group 3) were recruited for this cross-sectional investigation in the Department of Gastroenterology in Daqing Oilfield General Hospital from July 2013 to May 2014. The MlALDI-TOF-MS was used to measure the methylation levels of Runx3 in all of the subjects. Real-time quantitative reverse transcription polymerase chain reaction and western blotting were chosen to determine the expression levels of Runx3. The correlations between methylation levels of Runx3 among these CAG patients and their prognosis were shown by logistic regression models. The results demonstrated that the methylation levels of CpG13, CpG14, and CpG15 in Runx3 were higher in Group 3 than those in Groups 1 and 2 (P <0.05), whereas the mRNA and protein expression levels of Runx3 were lower in Group 3 than those in Groups 1 and 2 (P <0.05). There were significantly negative correlations between the methylation levels of Runx3 with its expression and the healing prognosis of CAG patients. In brief, this study proved that the hypermethylation modifications of CpG13, CpG14, and CpG15 in the promoter region of Runx3 could result in the down regulation of Runx3 expression to affect the prognosis of CAG. So the methylation levels of these CpG sites in Runx3 in the peripheral blood can be used as the biomarker for predicting the healing prognosis of CAG patients. PMID:27196446

  13. An Observational Study on Aberrant Methylation of Runx3 With the Prognosis in Chronic Atrophic Gastritis Patients

    PubMed Central

    Zhao, Chunna; Li, Ping; Zhang, Lili; Wang, Bei; Xiao, Lili; Guo, Feng; Wei, Yueguang

    2016-01-01

    Abstract The aim of this study is to discuss whether the methylation levels of Runx3 could be used as the early biomarker for predicting the prognosis in chronic atrophic gastritis (CAG) patients. A total of 200 subjects including 60 controls without CAG (Group 1), 70 patients with mild CAG (Group 2), and 70 patients with moderate and severe CAG (Group 3) were recruited for this cross-sectional investigation in the Department of Gastroenterology in Daqing Oilfield General Hospital from July 2013 to May 2014. The MlALDI-TOF-MS was used to measure the methylation levels of Runx3 in all of the subjects. Real-time quantitative reverse transcription polymerase chain reaction and western blotting were chosen to determine the expression levels of Runx3. The correlations between methylation levels of Runx3 among these CAG patients and their prognosis were shown by logistic regression models. The results demonstrated that the methylation levels of CpG13, CpG14, and CpG15 in Runx3 were higher in Group 3 than those in Groups 1 and 2 (P <0.05), whereas the mRNA and protein expression levels of Runx3 were lower in Group 3 than those in Groups 1 and 2 (P <0.05). There were significantly negative correlations between the methylation levels of Runx3 with its expression and the healing prognosis of CAG patients. In brief, this study proved that the hypermethylation modifications of CpG13, CpG14, and CpG15 in the promoter region of Runx3 could result in the down regulation of Runx3 expression to affect the prognosis of CAG. So the methylation levels of these CpG sites in Runx3 in the peripheral blood can be used as the biomarker for predicting the healing prognosis of CAG patients. PMID:27196446