987 resultados para 1ST TRIMESTER
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Residual stress having been further reduced, selected infrared coatings composed of thin films of (PbTe/ ZnS (or ZnSe) can now be made which comply with the durability requirements of MIL-48616 whilst retaining transparency. Such improved durability is due to the sequence:- i) controlled deposition, followed by ii) immediate exposure to air, followed by iii) annealing in vacuo to relieve stress. (At the time of writing we assume the empiric procedure "exposure to air/annealing in vacuo" acts to relieve the inherent stresses of deposition). As part of their testing, representative sample filters prepared by the procedure are being assembled for the shuttle's 1st Long Duration Exposure Facility (to be placed in earth orbit for a considerable period and then recovered for analysis). The sample filters comprise various narrowband-designs to permit deduction of the constituent thin film optical properties. The Reading assembly also contains representative sample of the infrared crystals, glasses, thin-film absorbers and bulk absorbers, and samples of shorter-wavelength filters prepared similarly but made with Ge/SiO. Findings on durability and transparency after exposure will be reported.
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The proceedings of the conference
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Carbon and nitrogen stable isotope ratios were measured in 157 fish bone collagen samples from 15 different archaeological sites in Belgium which ranged in ages from the 3rd to the 18th c. AD. Due to diagenetic contamination of the burial environment, only 63 specimens produced results with suitable C:N ratios (2.9–3.6). The selected bones encompass a wide spectrum of freshwater, brackish, and marine taxa (N = 18), and this is reflected in the δ13C results (−28.2‰ to −12.9%). The freshwater fish have δ13C values that range from −28.2‰ to −20.2‰, while the marine fish cluster between −15.4‰ and −13.0‰. Eel, a catadromous species (mostly living in freshwater but migrating into the sea to spawn), plots between −24.1‰ and −17.7‰, and the anadromous fish (living in marine environments but migrating into freshwater to spawn) show a mix of freshwater and marine isotopic signatures. The δ15N results also have a large range (7.2‰ to 16.7‰) indicating that these fish were feeding at many different trophic levels in these diverse aquatic environments. The aim of this research is the isotopic characterization of archaeological fish species (ecology, trophic level, migration patterns) and to determine intra-species variation within and between fish populations differing in time and location. Due to the previous lack of archaeological fish isotope data from Northern Europe and Belgium in particular, these results serve as an important ecological backdrop for the future isotopic reconstruction of the diet of human populations dating from the historical period (1st and 2nd millennium AD), where there is zooarchaeological and historical evidence for an increased consumption of marine fish.
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In a proof-of-concept study, Britton et al. (2008) demonstrated that the isotopic composition of halophytic plants can be traced in the skeletal tissues of their animal consumers. Here we apply the method to domestic herbivore remains (n = 303) from nine archaeological sites in or near the Flemish coastal plain (Belgium), where, prior to embankments, salt-marshes offered extensive pasture grounds for domestic herbivores. The sites span a period of ∼1500 years (Roman to late medieval period), during which the coastal landscape was progressively transformed from little managed wetlands to a fully embanked polder area. The bulk collagen data show variations between sites and over time, which are consistent with this historical framework and are interpreted as reflecting environmental change and differences in animal management in the coastal plain throughout the late Holocene. The study demonstrates the immense value of faunal stable isotope analysis for characterising coastal husbandry strategies beyond the means of traditional zooarchaeological techniques.
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Considering the potential role of macrophage migration inhibitory factor (MIF) in the inflammation process in placenta when infected by pathogens, we investigated the production of this cytokine in chorionic villous explants obtained from human first-trimester placentas stimulated with soluble antigen from Toxoplasma gondii (STAg). Parallel cultures were performed with villous explants stimulated with STAB, interferon-gamma (IFN-gamma), or STAB plus IFN-gamma. To assess the role of placental MIF on monocyte adhesiveness to human trophoblast, explants were co-cultured with human myelomonocytic THP-1 cells in the presence or absence of supernatant from cultures treated with STAB (SPN), SPN plus anti-MIF antibodies, or recombinant MIF. A significantly higher concentration of MIF was produced and secreted by villous explants treated with STAB or STAB plus IFN-gamma after 24-hour culture. Addition of SPN or recombinant MIF was able to increase THP-1 adhesion, which was inhibited after treatment with anti-MIF antibodies. This phenomenon was associated with intercellular adhesion molecule expression by villous explants. Considering that the processes leading to vertical dissemination of T. gondii remain widely unknown, our results demonstrate that MIF production by human first-trimester placenta is up-regulated by parasite antigen and may play an essential role as an autocrine/paracrine mediator in placental infection by T. gondii.
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Morphological structures of the head of 1st and 5th instar nymphs of Triatoma circummaculata and Triatoma rubrovaria were revealed by analysis using scanning electron microscopy (SEM). Differences between Ist and 5th instar nymphs of these two species were observed in the postocular callosity, the number of ommatidia and tapered hair, the small segment between antennal segments, the rostrum third segment and slit lines. These slit lines were different only in the 5th instar. Similarities observed were the presence of tapered hairs in the joints, and the type of sensilla in the antennal segments. Only the Ist instar shows anteclypeus and gena sensilla. The antennal segments comprise the following types of sensilla: basiconica, bristles type I, bristles type II, bristles type III, campaniformia, coeloconica, chemosensilla, placodea, trichobothria and trichoidea. We describe here for the first time six (3+3) sensilla basiconica on the dorsal portion of the first segment of the rostrum. (C) 2000 Elsevier B.V. Ltd. All rights reserved.
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The research aimed two objectives: 1st) identifying and describing the metaphors of the inflation, in a corpus of 18 texts of economic journalism, from Joelmir Beting, written in the last trimester of 2002, at the moment of the government s transition of president Fernando Henrique Cardoso to Luiz Inácio Lula Da Silva. 2nd) verifying the recognition of the metaphors by the students of the basic education of a private school from Natal. 91 metaphors had been identified, analyzed in the perspective of the conceptual metaphor s theory, by Lakoff and Johnson (2002), on the basis of the distinction between conceptual metaphor and metaphoric expressions, and between domain-source/domain-target. 10 underlying conceptual metaphors had been inferred, being that the domains-source used more frequently to characterize the inflation had been those ones according to the human being and the animals and, of a less imaginable form, to the ways of transport (car, aircraft). These general conceptual metaphors had been unfolded in other s more specific ones ( animal specifying itself in lion , dragon , dog , etc.). Another result was the identification of metaphoric expressions with two or more meanings , with relation to more than one conceptual metaphor or explicit, in the same expression, two domains-source (for example: armored dragon ) and contributes, of a relevant form, for the semantic struturation of the text. The understanding of the metaphors was verified through an activity of domains-source s identification (10 metaphoric statements and fulfilling of the gap in the phrase the inflation is a/an ) applied in a group of 8th year of the basic education (12-13 years old, with 14 girls and 17 boys) from a school of good social and economic positions from Natal-RN. There weren t great difficulties on the part of the students in recognizing the domains-source involved: about 80% to the great majority of the statements
Resumo:
The research aimed two objectives: 1st) identifying and describing the metaphors of the inflation, in a corpus of 18 texts of economic journalism, from Joelmir Beting, written in the last trimester of 2002, at the moment of the government s transition of president Fernando Henrique Cardoso to Luiz Inácio Lula Da Silva. 2nd) verifying the recognition of the metaphors by the students of the basic education of a private school from Natal. 91 metaphors had been identified, analyzed in the perspective of the conceptual metaphor s theory, by Lakoff and Johnson (2002), on the basis of the distinction between conceptual metaphor and metaphoric expressions, and between domain-source/domain-target. 10 underlying conceptual metaphors had been inferred, being that the domains-source used more frequently to characterize the inflation had been those ones according to the human being and the animals and, of a less imaginable form, to the ways of transport (car, aircraft). These general conceptual metaphors had been unfolded in other s more specific ones ( animal specifying itself in lion , dragon , dog , etc.). Another result was the identification of metaphoric expressions with two or more meanings , with relation to more than one conceptual metaphor or explicit, in the same expression, two domains-source (for example: armored dragon ) and contributes, of a relevant form, for the semantic struturation of the text. The understanding of the metaphors was verified through an activity of domains-source s identification (10 metaphoric statements and fulfilling of the gap in the phrase the inflation is a/an ) applied in a group of 8th year of the basic education (12-13 years old, with 14 girls and 17 boys) from a school of good social and economic positions from Natal-RN. There weren t great difficulties on the part of the students in recognizing the domains-source involved: about 80% to the great majority of the statements
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Objective: To determine whether the fatty acid composition of mid-trimester amniotic fluid differs by ethnicity and pregnancy outcome. Methods: Fatty acid composition was analyzed by gas chromatography in 198 women undergoing amniocentesis at 15-19 weeks gestation. Cytokine levels were determined by ELISA in a subgroup of 52 subjects. Results: The major fatty acids detected were palmitic acid (31.8%) and stearic acid (31.5%). The n-6 polyunsaturated fatty acids (PUFA), linoleic acid (LA, 18: 2) and arachidonic acid (AA, 20: 4), were 11.3%, while the n-3 PUFA fatty acids, alpha linolenic acid (ALA, 18: 3) and docosahexaenoic acid (DHA, 22: 6), were 3.8% of the total. Palmitic acid was a higher percentage in Asians (40.5%) and Whites (34.5%) than in Blacks (22.2%) and Hispanics (23.7%) (p <= 0.0012). Oleic acid (18:1 n-9) was a higher percentage in Blacks (12.2%) and Hispanics (12.1%) than in Whites (9.2%) or Asians (7.5%) (<= 0.0002). LA and AA were higher in Blacks (9.0%, 5.4%) and Hispanics (8.6%, 4.1%) than in Whites (6.1%, 3.7%) and Asians (5.5%, 2.9%) (p <= 0.0002). DHA did not differ among the ethnic groups or according to pregnancy outcome. A reduced palmitic acid percentage was identified in the six women with preeclampsia (p = 0.0233). Tumor necrosis factor-alpha levels were inversely proportional to the palmitic acid percentage (p = 0.0275) and positively associated with the percentages of stearic (18:0) (p = 0.0132) and oleic (p = 0.0290) acids. Conclusions: Amniotic fluid fatty acid composition differed among the ethnic groups and may influence inflammatory mediator production and susceptibility to preeclampsia.