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51.
In a prospective study, 48 fetuses were evaluated with Doppler ultrasound after 34 weeks and classified, according to the cerebroplacental ratio (CPR) and estimated fetal weight (EFW), into fetuses with normal growth and fetuses with late-onset fetal growth restriction (LO-FGR). Overexpression of miRNAs from neonatal cord blood belonging to LO-FGR fetuses, was validated by real-time PCR. In addition, functional characterization of overexpressed miRNAs was performed by analyzing overrepresented pathways, gene ontologies, and prioritization of synergistically working miRNAs. Three miRNAs: miR-25-3p, miR-185-5p and miR-132-3p, were significantly overexpressed in cord blood of LO-FGR fetuses. Pathway and gene ontology analysis revealed over-representation of certain molecular pathways associated with cardiac development and neuron death. In addition, prioritization of synergistically working miRNAs highlighted the importance of miR-185-5p and miR-25-3p in cholesterol efflux and starvation responses associated with LO-FGR phenotypes. Evaluation of miR-25-3p; miR-132-3p and miR-185-5p might serve as molecular biomarkers for the diagnosis and management of LO-FGR; improving the understanding of its influence on adult disease.  相似文献   
52.
In this work, we have investigated by differential scanning calorimetry the enthalpy relaxation of two poly[methyl(α-n-alkyl)acrylates] in which it is possible to change the length of the two alkyl chains. In particular, we have evaluated the Narayanaswamy parameter, which controls relative contribution of temperature and of structure to the relaxation times, by two methods: Grenet's method (GM) and the peak-shift method (PSM). The data obtained show that both methods lead to equivalent results. Nevertheless, PSM requires fewer experiments than GM, and PSM appears to be more practical. The results obtained on the two acrylates show that the parameter x increases with the lateral chain length, that is to say, that the temperature effects increase as the length of the alkyl chain is increased.  相似文献   
53.
Rice bran is considered in Mexico as “waste”, useful only for feeds. As considerable amounts of oil are available in rice bran, it might be worthwhile to stabilize it and extract the edible oil before using it for feedstuffs. Precisely these oils are responsible for rice bran rapid deterioration, particularly in climatic conditions such as those prevalent in Mexico's tropical areas (high humidity and high temperature). This paper deals with the study of the effect of pH during extrusion of fresh rice bran in order to inactivate lipid‐breaking enzymes. Hydrochloric acid or calcium hydroxide, Ca(OH)2, were added at 0, 1, 5, 10% (dry basis), and moisture content of the bran samples was varied (20, 30, 40%, dry basis) in a 32 factorial design to corroborate its effect at acid and alkaline pH range. Free fatty acids (FFA) increase was the control variable. Extruded samples were stored at room temperature (between 20 and 28 °C) using a non‐extruded sample as control to assess the shelf life effects. Results indicate that in acid‐extruded samples, the increase in FFA concentration after 98 days was much less than in the unmodified‐pH or alkaline samples. The lowest FFA increase after 3 months of storage time was <10 mg FFA/g rice bran using extrusion with no water or chemicals added or using extrusion adding HCl, irrespective of the moisture content of rice bran.  相似文献   
54.
The objective was to evaluate the effect of soy fermented product intake on the corporal weight and bone tissue of ovariectomized mature rats. This product was fermented with Enterococcus faecium and Lactobacillus jugurti and enriched with isoflavones and calcium. The animals were divided in 5 groups: sham-ovariectomized; ovariectomized; ovariectomized treated with soy fermented product enriched with isoflavones and calcium; ovariectomized treated with soy fermented product enriched with calcium and ovariectomized treated with non-fermented product enriched only with calcium. In order to evaluate the effect of the tested product on bone tissue (femur and tibia), the following parameters were analyzed: length; mechanical assay of three points; density (Archimedes principle); mineral content; calcium content; measure of the trabecular widths. The corporal weight of group treated with soy fermented product containing isoflavones and calcium showed no statistical difference from sham-ovariectomized group and trabecular widths tended to have larger than ovariectomized group. However, there was no significant difference to the other evaluated parameters in result of the diverse treatments. Thus, soy fermented product enriched with isoflavones and calcium inhibited the increasing of corporal weight caused by ovariectomy and revealed a tendency to trabecular protection after castration.  相似文献   
55.
Steryl glucosides (SG) are common contaminants in biodiesel that form precipitates, which form and cause problems due to fouling during transport and storage. Therefore, their quantification is necessary to assess the quality of this fuel. The methods currently available for SG analysis require expensive instrumentation, need a previous concentration step by solid‐phase extraction (SPE) or are of limited use for the quantitative assessment. We developed an enzymatic method for SG quantification in biodiesel samples based on the hydrolysis of the glucoside catalyzed by a broadly specific beta glucosidase and the subsequent determination of the glucose released by the reaction. The method is non‐expensive, sensitive and was adapted to 96‐well format fluorescence plate reader, making it useful for the parallel assay of multiple samples. The enzymatic assay presented here represent a valuable tool for both quality control and the development of improved biodiesel production and purification procedures.  相似文献   
56.
57.
Flow‐dependent fish specialists require specific conditions for reproduction, so the success and reproductive intensity of these animals are determined by the flood regime. Thus, this study investigated the spatial and temporal reproductive patterns of fish, especially migratory Prochilodus species (flow‐dependent specialists) in an unusual period of low flow in the Pará River sub‐basin, one of the main tributaries of the upper São Francisco River. For this, ichthyoplankton collections were carried out between November 2013 and February 2014. Data were analysed considering the spatial and temporal variations in density of eggs and larvae for the upper, middle, and lower portions of the Pará River sub‐basin, and correlating this to some environmental variables. The results showed that the small headwater stretch of the Pará River is one relevant spawning area for migratory fish species. However, this area is isolated by the Cajuru reservoir, which makes it uncertain the recruitment of these embryos, due to interruption of natural drift between spawning/nursery areas caused for reservoirs. Larvae of newly hatched migratory species found in tributaries of the lower Pará River sub‐basin also indicate these species use these tributaries as spawning grounds and migratory routes. The period in which the research was conducted represented the most atypical low flow, one in the last 75 years, resulting in the low variability in the environmental parameters. Although few parameters increased briefly in this low flow period influenced by greater rainfall in December, this precipitation was possibly responsible for the final gonadal maturation and spawning of migratory species.  相似文献   
58.
Here we present thermoelectric and mechanical properties of n-type filled-skutterudites produced by a combination of melt spinning of pre-melted charges with subsequent consolidation by spark plasma sintering, a process we refer to as MS-SPS. This combination of processing steps leads to phase-pure n-type filled-skutterudites and obviates more energy and time intensive annealing steps. We show that both the thermoelectric properties and the tensile fracture strength compare favorably to materials made by traditional methods. The process is scalable to at least 80 g billets, such that the transport properties measured on test bars harvested from these larger billets compare favorably to those measured on lab-scale billets (5 g total billet mass). ZT values approaching 1.1 at 750 K were observed in materials made by MS-SPS. In addition, the tensile fracture strength of test bars cut from an 80 g billet is ∼128 MPa at room temperature and decreases with increasing temperature. Fractography of the test bars reveals that the majority failed due to surface and edge flaws with few failures due to volume type flaws. This indicates that the powder metallurgical methods employed to produce these samples is mature.  相似文献   
59.
The purpose of this work was to use image analysis to study the microstructural properties of haemoglobin gels, with structural changes induced by pH conditions, and their correlations with physical properties such as texture and water holding capacity (WHC). Two types of networks showing great differences in the dimensions of the gel structure were obtained as influenced by pH. At pH < 5.5 there was a shift from an aggregated to a fine-stranded gel type. Fractal dimension values revealed that more complex structures corresponded to softest and non-exudative gels. Lacunarity and pore size, which were used to study the pore distribution within the network, confirmed that softest gels with high WHC showed large number of small cavities. Finally, correlations between textural attributes, i.e. springiness and adhesiveness, and spatial variability, referred quantitatively to the degree of compactness, were also established.  相似文献   
60.
Department of Intelligent Hydraulics and Automation (IHA) of Tampere University of Technology has been involved in the European Fusion program since 1994 within the ITER reactor maintenance activities. In this paper we discuss the design and development of a six degrees of freedom water hydraulic manipulator with a force feedback for teleoperation tasks. The manipulator is planned to be delivered to Divertor Test Platform 2 (DTP2) during year 2008. The paper also discusses the possibility to improve the fail safe and redundant operation of the manipulator. During the design of the water hydraulic manipulator, special provisions have been made in order to meet the safety requirements such as servo valve block for redundant operation and safety vane brakes for fail safe operation.  相似文献   
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