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991.
Chen CM Thiering E Doekes G Zock JP Bakolis I Norbäck D Sunyer J Villani S Verlato G Täubel M Jarvis D Heinrich J 《Indoor air》2012,22(1):24-32
Endotoxin exposures have manifold effects on human health. The geographical variation and determinants of domestic endotoxin levels in Europe have not yet been extensively described. To investigate the geographical variation and determinants of domestic endotoxin concentrations in mattress dust in Europe using data collected in the European Community Respiratory Health Survey follow-up (ECRHS II). Endotoxin levels were measured in mattress dust from 974 ECRHS II participants from 22 study centers using an immunoassay. Information on demographic, lifestyle, and housing characteristics of the participants was obtained in face-to-face interviews. The median endotoxin concentration in mattress dust ranged from 772 endotoxin units per gram (EU/g) dust in Reykjavik, Iceland, to 4806 EU/g in Turin, Italy. High average outdoor summer temperature of study center, cat or dog keeping, a high household crowding index, and visible damp patches in the bedroom were significantly associated with a higher endotoxin concentrations in mattress dust. There is a large variability in domestic endotoxin levels across Europe. Average outdoor summer temperature of study center, which explains only 10% of the variation in domestic endotoxin level by center, is the strongest meteorological determinant. The observed variation needs to be taken into account when evaluating the health effects of endotoxin exposures in international contexts. PRACTICAL IMPLICATIONS: The incoherent observations of the health effects of endotoxin may be partly owing to the geographical heterogeneity of endotoxin exposure. Therefore, the observed variation should be considered in further studies. Measurements of indoor endotoxin are recommended as an indicator for the level of exposures of individual domestic environments. 相似文献
992.
Heinrich Rübsam Martin Krottenthaler Martina Gastl Thomas Becker 《Starch - St?rke》2012,64(9):683-695
Starch is the most important source of human food energy and also an important polymer for biofuels, processed food, and pharmaceutical industries. Precise determination of structural and functional properties of starch has been an outstanding factor for the improvement of dissolution and degradation processes, which are important procedures for commercial applications. Distinct separation techniques coupled with multiple detection methods such as Size Exclusion Chromatography (SEC), Field Flow fractionation (FFF), Analytical Ultracentrifugation, and Hydrodynamic Chromatography have provided powerful information about starch conformation. In the present review, we describe the usefulness and limitations of different separation methods particularly SEC and FFF, which are currently widely used. 相似文献
993.
Patrick Guertler Christina Brandl Heinrich H. D. Meyer Ales Tichopad 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(3):195-202
Public concern has been expressed on the use of genetically modified (gm) maize MON810 as animal feed and for human consumption. Several studies have been conducted on potential effects of feeding MON810 to livestock focusing on animal performance, animal health and fate of recombinant DNA or protein. Though, no information on effects of feeding gm maize on the gene expression level is available so far. From 2005 until 2007, a study with 36 lactating dairy cows fed gm maize (N?=?18, MON810) or the near-isogenic counterpart (N?=?18) was carried out, investigating the fate of recombinant DNA and protein. After a period of 25?months, ten cows fed transgenic maize and seven cows fed near-isogenic maize were slaughtered due to operational reasons. In a short follow-up study, tissues of the gastrointestinal tract and samples from liver were used for gene expression analysis of major genes of the inflammation, cell cycle and apoptosis pathways. Statistical analysis of the examined gene expression pattern revealed no significant difference in the gene expression profile of cows fed transgenic or near-isogenic feed ration. Therefore, it can be assumed that compared to near-isogenic feed, gm maize MON810 does not have any effect on major genes involved in apoptosis, inflammation and cell cycle in the gastrointestinal tract and in the liver of dairy cows. 相似文献
994.
Nasir Mahmood Asad Ullah Khan Zulfiqar Ali Mohammad Sohail Khan Anwar‐Ul Haq Klaus Werner Stöckelhuber Uwe Gohs Gert Heinrich 《应用聚合物科学杂志》2012,123(6):3635-3643
This study deals with the preparation and characterization of novel thermoplastic polyurethane–urea (TPUU) and carboxylated acrylonitrile butadiene rubber (XNBR) blends. Blends of different compositions were prepared in tetrahydrofuran using a solution technique, following an ultra‐sonication. The chemical reaction between the two inherently immiscible blend phases was determined with the help of Fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) spectroscopy and 1H‐nuclear magnetic resonance (1H‐NMR) spectroscopy. The identification of the new peaks in the FTIR‐ATR spectra corroborates the existence of chemical reaction between the carboxylic functional group of XNBR and the amide group of the TPUU. In addition, an increase in the network crosslink density of the blend investigated using 1H‐NMR spectroscopy further supports the occurrence of the chemical reaction between the XNBR and the TPUU. The scanning and transmission electron micrographs of the blend morphology show a uniform dispersion of the minor TPUU phase in the XNBR. Furthermore, the existence of a single glass transition peak also confirms the enhancement in the interfacial miscibility. Additionally, the incorporation of 5 wt % of organomodified montmorillonite nanoclay improves the mechanical properties to a considerable extent in comparison with the unfilled blend elastomeric material. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
995.
Strategies for the identification of allosteric modulators of chemokine receptors largely rely on various cell‐based functional assays. Radioligand binding assays are typically not available for allosteric binding sites. We synthesized, purified, and applied the first tritium‐labeled allosteric modulator of the human chemokine receptor CXCR3 (RAMX3, [3H]N‐{1‐[3‐(4‐ethoxyphenyl)‐4‐oxo‐3,4‐dihydropyrido[2,3‐d]pyrimidin‐2‐yl]ethyl}‐2‐[4‐fluoro‐3‐(trifluoromethyl)phenyl]‐N‐[(1‐methylpiperidin‐4‐yl)methyl]acetamide). RAMX3 is chemically derived from 8‐azaquinazolinone‐type allosteric modulators and binds to the CXCR3 receptor with a Kd value of 1.08 nM (specific activity: 80.4 Ci mmol?1). Radioligand displacement assays showed potent negative cooperativity between RAMX3 and chemokine CXCL11, providing a basis for the use of RAMX3 to investigate other potential allosteric modulators. Additionally, the synthesis and characterization of a number of other full and truncated 8‐azaquinazoline analogues were used to validate the binding properties of RAMX3. We demonstrate that RAMX3 can be efficiently used to facilitate the discovery and characterization of small molecules as allosteric modulators of the CXCR3 receptor. 相似文献
996.
Elisa Heinrich Mora Cate Heine Jacob J. Jackson Geoffrey B. West Vicky Chuqiao Yang Christopher P. Kempes 《Journal of the Royal Society Interface》2021,18(181)
Urban scaling analysis, the study of how aggregated urban features vary with the population of an urban area, provides a promising framework for discovering commonalities across cities and uncovering dynamics shared by cities across time and space. Here, we use the urban scaling framework to study an important, but under-explored feature in this community—income inequality. We propose a new method to study the scaling of income distributions by analysing total income scaling in population percentiles. We show that income in the least wealthy decile (10%) scales close to linearly with city population, while income in the most wealthy decile scale with a significantly superlinear exponent. In contrast to the superlinear scaling of total income with city population, this decile scaling illustrates that the benefits of larger cities are increasingly unequally distributed. For the poorest income deciles, cities have no positive effect over the null expectation of a linear increase. We repeat our analysis after adjusting income by housing cost, and find similar results. We then further analyse the shapes of income distributions. First, we find that mean, variance, skewness and kurtosis of income distributions all increase with city size. Second, the Kullback–Leibler divergence between a city’s income distribution and that of the largest city decreases with city population, suggesting the overall shape of income distribution shifts with city population. As most urban scaling theories consider densifying interactions within cities as the fundamental process leading to the superlinear increase of many features, our results suggest this effect is only seen in the upper deciles of the cities. Our finding encourages future work to consider heterogeneous models of interactions to form a more coherent understanding of urban scaling. 相似文献
997.
998.
The purpose of this article is to study the accuracy of a number of simple approximate equations for the spherical albedo r (or the hemispherical reflectance under diffuse illumination conditions) of semi‐infinite light scattering absorbing media, using numerical solutions of the nonlinear integral equation for the reflection function of a semi‐infinite turbid medium, as formulated by V. A. Ambartsumian. We find that the van de Hulst approximation provides the most accurate approximation for the diffuse reflectance r under diffuse illumination conditions. The value of r depends almost exclusively on the value of the similarity parameter , where ω0 is the single scattering albedo and g is the asymmetry parameter. A simple approach to derive the normalized absorption spectra of particulate matter from reflectance measurements is proposed. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 491–497, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20262 相似文献
999.
Lobell M Hendrix M Hinzen B Keldenich J Meier H Schmeck C Schohe-Loop R Wunberg T Hillisch A 《ChemMedChem》2006,1(11):1229-1236
The need for in silico characterization of HTS hit structures as part of a data-driven hit-selection process is demonstrated. A solution is described in the form of an in silico ADMET traffic light and PhysChem scoring system. This has been extensively validated with in-house data at Bayer, published data, and a collection of launched small-molecule oral drugs. 相似文献
1000.