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991.
Andreas Ludwig Johann Mogeritsch Monika Grasser 《Transactions of the Indian Institute of Metals》2009,62(4-5):433-436
A transparent non-facetted/non-facetted peritectic system was used for in-situ studies of peritectic growth morphologies above and below the limit of constitutional undercooling. For a hypo-peritectic alloy with near peritectic composition an oscillatory growth mode was found for velocities in the cellular/dendritic regime. It is demonstrated that the co-existence of two distinct cellular/dendritic solid/liquid interfaces which try to reach stable growth conditions causes this oscillations. Additionally, it is shown that on reducing the withdrawal speed the two distinct interfaces arrange into an isothermal coupled peritectic growth mode. 相似文献
992.
Evaluation of plant products from the Legnicko–Głogowski region for their contamination with arsenic
Monika Bronkowska Danuta Figurska-CiuraDagmara Orzeł Marzena StyczyńskaJoanna Wyka Karolina LoźnaAlicja Żechałko-Czajkowska Jadwiga Biernat 《Food chemistry》2008
Contents of arsenic were determined in plant products originating from the region of two copperworks, G?ogów and Legnica. Analyses were carried out by means of atomic absorption spectrometry, using an MHS-10 unit for hydride generation (acetylene/argon), after wet mineralisation of samples. 相似文献
993.
Monika Englert-Golon Mirosaw Andrusiewicz Aleksandra bikowska Magorzata Chmielewska Stefan Sajdak Magorzata Kotwicka 《International journal of molecular sciences》2021,22(12)
Ovarian cancer remains the leading cause of death due to gynecologic malignancy. Estrogen-related pathways genes, such as estrogen receptors (ESR1 and ESR2) and their coregulators, proline-, glutamic acid-, and leucine-rich protein 1 (PELP1), and proto-oncogene tyrosine-protein kinase c-Src (SRC) are involved in ovarian cancer induction and development, still they require in-depth study. In our study, tissue samples were obtained from 52 females of Caucasian descent (control group without cancerous evidence (n = 27), including noncancerous benign changes (n = 15), and the ovarian carcinoma (n = 25)). Using quantitative analyses, we investigated ESRs, PELP1, and SRC mRNA expression association with ovarian tumorigenesis. Proteins’ presence and their location were determined by Western blot and immunohistochemistry. Results showed that PELP1 and SRC expression levels were found to differ in tissues of different sample types. The expression patterns were complex and differed in the case of ovarian cancer patients compared to controls. The most robust protein immunoreactivity was observed for PELP1 and the weakest for ESR1. The expression patterns of analyzed genes represent a potentially interesting target in ovarian cancer biology, especially PELP1. This study suggests that specific estrogen-mediated functions in the ovary and ovary-derived cancer might result from different local interactions of estrogen with their receptors and coregulators. 相似文献
994.
995.
Marie Suchanová Jana Hajšlová Monika Tomaniová Vladimír Kocourek Luboš Babička 《Journal of the science of food and agriculture》2008,88(8):1307-1317
BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) represent a group of organic compounds containing two or more aromatic rings. Their control in the human food chain is required due to the mutagenic and carcinogenic potential, exhibited in vertebrates. In the present study, the occurrence of PAHs in 36 cheeses smoked by various processes was investigated. RESULTS: PAH concentrations (sum of 15 US EPA PAHs) found in samples smoked under controlled industrial conditions were at level 0.11 µg kg?1, whereas in ‘home‐made’ cheeses, the PAH content was up to 10 times higher. A similar trend was observed for B[a]P, a marker compound representing carcinogenic PAHs. While its levels in commercial products prepared by controlled smoking technologies were close to the limit of quantification (0.03 µg kg?1); in household samples, the B[a]P content ranged from 0.6 to 0.9 µg kg?1. Significantly higher amounts of PAHs (up to three to six times) were found in surface layers as compared to internal parts of cheese. CONCLUSION: Although smoked cheese is a popular food, only several papers have focused on PAH levels in these products. This paper evaluates the contribution of different smoking technologies to PAH contamination of several cheeses and thus can help in a risk assessment associated with their consumption. Moreover, the study shows the concentration ratios of selected PAHs, from which the type of smoking technology can be indicated. The results obtained in this study also supported the suggestion of the EU Scientific Committee on Food to use benzo[a]pyrene as an indicator of the occurrence of higher‐molecular mass PAHs. Copyright © 2008 Society of Chemical Industry 相似文献
996.
Use of vacuum technology in crystal pulling and lamination application in manufacturing of photovoltaic modules Dry compressing screw type vacuum pumps such as the SCREWLINE SP 630/250 are designed to reduce cost of ownership in crystal pulling plant and in lamination processes. The construction of gear house sealings, the easy maintenance of the pump on site and the use of gas ballast guarantee a very reliable performance, and long maintenance and service intervals. In the case of crystal pulling the process does not even need a dust separator at the inlet of the vacuum pump. 相似文献
997.
Monika Rumpler Alexander Woesz John W C Dunlop Joost T van Dongen Peter Fratzl 《Journal of the Royal Society Interface》2008,5(27):1173-1180
Tissue formation is determined by uncountable biochemical signals between cells; in addition, physical parameters have been shown to exhibit significant effects on the level of the single cell. Beyond the cell, however, there is still no quantitative understanding of how geometry affects tissue growth, which is of much significance for bone healing and tissue engineering. In this paper, it is shown that the local growth rate of tissue formed by osteoblasts is strongly influenced by the geometrical features of channels in an artificial three-dimensional matrix. Curvature-driven effects and mechanical forces within the tissue may explain the growth patterns as demonstrated by numerical simulation and confocal laser scanning microscopy. This implies that cells within the tissue surface are able to sense and react to radii of curvature much larger than the size of the cells themselves. This has important implications towards the understanding of bone remodelling and defect healing as well as towards scaffold design in bone tissue engineering. 相似文献
998.
Stephen Nauyoks Monika Wieligor T.W. Zerda Levente Balogh Tamas Ungar Peter Stephens 《Composites Part A》2009,40(5):566-572
Diamond–silicon carbide composites were sintered at 10 GPa and three different temperatures: 1600, 1800, and 2000 °C. Distributions of residual surface stresses in diamond crystals were obtained by the analysis of Raman band shifts and splitting. It was noted that stresses concentrate around points of contacts between diamond crystals. Average stress increase with increasing sintering temperature. Complementary information on average sizes of crystallites, concentration of stacking faults, and population of dislocations in both diamond and SiC were obtained from X-ray diffraction profile analysis. It was observed that for both diamond and silicon carbide phases the average crystallite sizes decrease. The population of dislocations in the diamond phase increases with increasing sintering temperature and the population fluctuates in the SiC phase. Concentration of stacking faults was significant only in SiC. 相似文献
999.
Obesity and the related disorders, diabetes, hypertension and hyperlipidemia have reached epidemic proportions world-wide. The influence of 70 plants, herbs and spices on peroxisome proliferators-activated receptor (PPAR)γ activation or antagonism, a drug target for metabolic syndrome, was investigated. Approximately 50 different plant extracts bound PPARγ in competitive ligand binding assay, including pomegranate, apple, clove, cinnamon, thyme, green coffee, bilberry and bay leaves. Five plant extracts transactivated PPARγ in chimeric GAL4-PPARγ-LBD system: nutmeg, licorice, black pepper, holy basil and sage. Interestingly, nearly all plant extracts antagonized rosiglitazone-mediated coactivator recruitment in time resolved fluorescence resonance energy transfer coactivator assay. The five transactivating extracts may function as selective PPARγ modulators (SPPARγMs), and the other extracts seem to be moderate antagonists or undetectable/weak SPPARγMs. As SPPARγMs improve insulin resistance without weight gain and PPARγ antagonists exert antiobesity action, a combination of these plants in diet could reduce obesity and the incidence of metabolic syndrome. 相似文献
1000.
The particle-based approach to sedimentation is extended to include velocity fluctuations that result in hydrodynamic diffusion. The vector process describing the joint values of position and velocity is Markov. Thus, no integration of velocity is required. Height-velocity “skeletons” for each particle are generated from a bivariate-normal distribution with means, variances, and covariance that depend on three parameters. For each particle, there is a unique region in which the vector of species concentrations determines that particle's parameters and hence its Markov process, but the concentrations in that region depend on the Markov processes of neighboring particles. Though only discrete values of height and velocity are generated, the model ensures that sample paths and particle velocities are continuous. Furthermore, steady-state velocities are normally distributed and velocity autocorrelations decay exponentially. Published experimental results indicate that both are excellent approximations. For polydisperse suspensions, the Markov model is much simpler than the standard hydrodynamic-diffusion model and represents the actual process much better. We simulate the sedimentation and fluidization of polydisperse suspensions and study the effects of two additional parameters: variance and autocorrelation decay rate of particle velocities. 相似文献