932 resultados para ES-SAGD. Heavy oil. Recovery factor. Reservoir modeling and simulation
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The time variable Earth’s gravity field provides the information about mass transport within the system Earth, i.e., the relationship of mass transport between atmosphere, oceans, and land hydrology. We recover the low-degree parameters of the time variable gravity field using microwave observations from GPS and GLONASS satellites and from SLR data to five geodetic satellites, namely LAGEOS-1/2, Starlette, Stella, and AJISAI. GPS satellites are particularly sensitive to specific coefficients of the Earth's gravity field, because of the deep 2:1 orbital resonance with Earth rotation (two revolutions of the GPS satellites per sidereal day). The resonant coefficients cause, among other, a “secular” drift (actually periodic variations of very long periods) of the semi-major axes of up to 5.3 m/day of GPS satellites. We processed 10 years of GPS and GLONASS data using the standard orbit models from the Center of Orbit Determination in Europe (CODE) with a simultaneous estimation of the Earth gravity field coefficients and other parameters, e.g., satellite orbit parameters, station coordinates, Earth rotation parameters, troposphere delays, etc. The weekly GNSS gravity solutions up to degree and order 4/4 are compared to the weekly SLR gravity field solutions. The SLR-derived geopotential coefficients are compared to monthly GRACE and CHAMP results.
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BACKGROUND: Variants in the complement cascade genes and the LOC387715/HTRA1, have been widely reported to associate with age-related macular degeneration (AMD), the most common cause of visual impairment in industrialized countries. METHODS/PRINCIPAL FINDINGS: We investigated the association between the LOC387715 A69S and complement component C3 R102G risk alleles in the Finnish case-control material and found a significant association with both variants (OR 2.98, p = 3.75 x 10(-9); non-AMD controls and OR 2.79, p = 2.78 x 10(-19), blood donor controls and OR 1.83, p = 0.008; non-AMD controls and OR 1.39, p = 0.039; blood donor controls), respectively. Previously, we have shown a strong association between complement factor H (CFH) Y402H and AMD in the Finnish population. A carrier of at least one risk allele in each of the three susceptibility loci (LOC387715, C3, CFH) had an 18-fold risk of AMD when compared to a non-carrier homozygote in all three loci. A tentative gene-gene interaction between the two major AMD-associated loci, LOC387715 and CFH, was found in this study using a multiplicative (logistic regression) model, a synergy index (departure-from-additivity model) and the mutual information method (MI), suggesting that a common causative pathway may exist for these genes. Smoking (ever vs. never) exerted an extra risk for AMD, but somewhat surprisingly, only in connection with other factors such as sex and the C3 genotype. Population attributable risks (PAR) for the CFH, LOC387715 and C3 variants were 58.2%, 51.4% and 5.8%, respectively, the summary PAR for the three variants being 65.4%. CONCLUSIONS/SIGNIFICANCE: Evidence for gene-gene interaction between two major AMD associated loci CFH and LOC387715 was obtained using three methods, logistic regression, a synergy index and the mutual information (MI) index.
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Cytokine-induced transcription of the serum amyloid A3 (SAA3) gene promoter requires a transcriptional enhancer that contains three functional elements: two C/EBP-binding sites and a third site that interacts with a constitutively expressed transcription factor, SAA3 enhancer factor (SEF). Deletion or site-specific mutations in the SEF-binding site drastically reduced SAA3 promoter activity, strongly suggesting that SEF is important in SAA3 promoter function. To further elucidate its role in the regulation of the SAA3 gene, we purified SEF from HeLa cell nuclear extracts to near homogeneity by using conventional liquid chromatography and DNA-affinity chromatography. Ultraviolet cross-linking and Southwestern experiments indicated that SEF consisted of a single polypeptide with an apparent molecular mass of 65 kDa. Protein sequencing, oligonucleotide competition and antibody supershift experiments identified SEF as transcription factor LBP-1c/CP2/LSF. Cotransfection of SEF expression plasmid with SAA3-luciferase reporter resulted in 3- to 5-fold activation of SAA3 promoter. Interestingly, when SEF-transfected cells were treated with either conditioned medium (CM) or interleukin (IL) 1, the SAA3 promoter was synergistically activated in a dose-dependent manner. Furthermore, when SEF-binding site was mutated, the response of SAA3 promoter to IL-1 or CM stimulation was abolished or drastically decreased, suggesting that SEF may functionally cooperate with an IL-1-inducible transcription factor. Indeed, our functional studies showed that NFκB is a key transcription factor that mediates the IL-1-induced expression of SAA3 gene, and that SEF can synergize with NFκBp65 to activate SAA3 promoter. By coimmunoprecipitation experiments, we found that SEF could specifically interact with NFκBp65, and that the association of these two factors was enhanced upon IL-1 and CM stimulation. This suggests that the molecular basis for the functional synergy between SEF and NFκB may be due to the ability of SEF to physically interact with NPκB. In addition to its interaction with SEF, NFκB-dependent activation also requires the weak κB site in the C element and its interaction with C/EBP. Besides its role in regulating SAA3 gene expression, we provide evidence that SEF could also bind in a sequence-specific manner to the promoters of α2-macroglobulin, Aα fibrinogen, and 6–16 genes and to an intronic enhancer of the human Wilm's tumor 1 gene, suggesting a functional role in the regulation of these genes. By coimmunoprecipitation experiments, we determined that SEF could specifically associate with both Stat3 and Stat2 upon cytokine stimulation. To examine the functional roles of such interactions, we evaluated the effects of SEF on the transcriptional regulation of two reporter genes: Aα fibrinogen and 6–16, which are IL-6- and interferon-α-responsive, respectively. Our results showed that cotransfection of SEF expression plasmid can activate the expression of Aα fibrinogen gene and 6–16 gene. Moreover, SEF can dramatically enhance the interferon-α-induced expression of 6–16 gene and IL-6-induced expression of Aα fibrinogen gene, suggesting that SEF may functionally cooperate with ISGF3 and Stat3 to mediate interferon-α and IL-6 signaling. ^ Our findings that SEF can interact with multiple cytokine-inducible transcription factors to mediate the expression of target genes open a new avenue of investigation of cooperative transcriptional regulation of gene expression, and should further our understanding of differential gene expression in response to a specific stimulus. In summary, our data provide evidence that SEF can mediate the signaling of different cytokines by interacting with various cytokine-inducible transcription factors. ^
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Need for cognition (NFC) reflects a relatively stable trait regarding the degree to which one enjoys and engages in cognitive endeavors. We examined whether the previously demonstrated one-dimensional structure of the German NFC Scale could be replicated in three samples of undergraduates and secondary school students. Moreover, we investigated the test-retest reliability of the German NFC Scale, which has not yet been tested. Further, we investigated whether the scale would be valid in a sample of secondary school students. Multigroup confirmatory factor analyses established the one-dimensional factor structure of the long form as well as the short form of the German NFC Scale for undergraduates (N = 559), students of academic track secondary schools (German Gymnasium; N = 555), and students of vocational track secondary schools (German Realschule; N = 486). The scale proved to have a high test-retest reliability in a university student sample (N = 43). For secondary school students, we again found a high test-retest reliability (N = 157), and also found the scale to be valid (N = 181).
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by Samuel Daiches
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Pressure–Temperature–time (P–T–t) estimates of the syn-kinematic strain at the peak-pressure conditions reached during shallow underthrusting of the Briançonnais Zone in the Alpine subduction zone was made by thermodynamic modelling and 40Ar/39Ar dating in the Plan-de-Phasy unit (SE of the Pelvoux Massif, Western Alps). The dated phengite minerals crystallized syn-kinematically in a shear zone indicating top-to-the-N motion. By combining X-ray mapping with multi-equilibrium calculations, we estimate the phengite crystallization conditions at 270 ± 50 °C and 8.1 ± 2 kbar at an age of 45.9 ± 1.1 Ma. Combining this P–T–t estimate with data from the literature allows us to constrain the timing and geometry of Alpine continental subduction. We propose that the Briançonnais units were scalped on top of the slab during ongoing continental subduction and exhumed continuously until collision.
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Copper, zinc, manganese, iron, nickel and molybdenum are essential micronutrients for plants. However, when present in excess they may damage the plant or decrease the quality of harvested plant products. Some other heavy metals such as cadmium, lead or mercury are not needed by plants and represent pollutants. The uptake into the roots, the loading into the xylem, the acropetal transport to the shoot with the transpiration stream and the further redistribution in the phloem are crucial for the distribution in aerial plant parts. This review is focused on long-distance transport of heavy metals via xylem and phloem and on interactions between the two transport systems. Phloem transport is the basis for the redistribution within the shoot and for the accumulation in fruits and seeds. Solutes may be transferred from the xylem to the phloem (e.g., in the small bundles in stems of cereals, in minor leaf veins). Nickel is highly phloem-mobile and directed to expanding plant parts. Zinc and to a lesser degree also cadmium are also mobile in the phloem and accumulate in meristems (root tips, shoot apex, axillary buds). Iron and manganese are characterized by poor phloem mobility and are retained in older leaves.
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This paper examines cross-country patterns of economic growth by estimating a stochastic frontier production function for 80 developed and developing countries and decomposing output change into factor accumulation, total factor productivity growth, and production efficiency improvement. In addition, this paper incorporates the quality of inputs in analyzing output growth, where the productivity of capital depends on its average age, while the productivity of labor depends on its average level of education. Our growth decomposition involves five geographic regions - Africa, East Asian, Latin America, South Asia, and the West. Factor growth, especially capital accumulation, generally proves much more important than either the improved quality of factors or total factor productivity growth in explaining output growth. The quality of capital positively and significantly affects output growth in all groups. The quality of labor, however, only possesses a positive and significant effect on output growth in Africa, East Asia, and the West. Labor quality owns a negative and significant effect in Latin America and South Asia.
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Hermann Pick
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Obesity, among both children and adults, is a growing public health epidemic. One area of interest relates to how and why obesity is developing at such a rapid pace among children. Despite a broad consensus about how controlling feeding practices relate to child food consumption and obesity prevalence, much less is known about how non-controlling feeding practices, including modeling, relate to child food consumption. This study investigates how different forms of parent modeling (no modeling, simple modeling, and enthusiastic modeling) and parent adiposity relate to child food consumption, food preferences, and behaviors towards foods. Participants in this experimental study were 65 children (25 boys and 40 girls) aged 3-9 and their parents. Each parent was trained on how to perform their assigned modeling behavior towards a food identified as neutral (not liked, nor disliked) by their child during a pre-session food-rating task. Parents performed their assigned modeling behavior when cued during a ten-minute observation period with their child. Child food consumption (pieces eaten, grams eaten, and calories consumed) was measured and food behaviors (positive comments toward food and food requests) were recorded by event-based coding. After the session, parents self-reported on their height and weight, and children completed a post-session food-rating task. Results indicate that parent modeling (both simple and enthusiastic forms) did not significantly relate to child food consumption, food preferences, or food requests. However, enthusiastic modeling significantly increased the number of positive food comments made by children. Children's food consumption in response to parent modeling did not differ based on parent obesity status. The practical implications of this study are discussed, along with its strengths and limitations, and directions for future research.^
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Ultrafiltration with tagged atoms was used to study physicochemical states (dissolved, colloidal, suspended) of Mn, Co, Ni, Zn, and Ce in bottom and interstitial waters collected in two areas of the Pacific Ocean with Fe-Mn nodules of different size, shape, structure and origin in different abundances. Use of filters with pore diameter of 0.05 ?m allowed to identify colloidal forms of the metals in bottom sediments and interstitial waters. It was demonstrated experimentally that differences in physicochemical situation in the studied areas could result in formation of nodules by different mechanisms, producing characteristic differences that were observed.