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81.
Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Two-phase flows in a mold of a slab caster are studied using water modeling, particle-image velocimetry (PIV), and computational fluid-dynamics techniques. Two-way coupled flows are observed in liquidgas systems, because both phases influence each other’s momentum transfer. In addition to this concept, PIV measurements indicate the existence of structurally coupled flows, where the velocity vectors of both phases observe similar orientations. When the drag forces of the liquid, exerted on the bubbles, exceed a certain value of the inertial forces of the liquid phase, at high mass loads of gas (ratio of mass flow rates of the gas phase and the liquid phase), the flow becomes structurally coupled. These types of flows promote large oscillations of the meniscus level. Two jets, liquid and bubble, were identified; the latter always reported larger angles than the first, independent of the gas load. Thus, a gas-rich jet is located closer to the lower edge of the submerged entry nozzle (SEN) port, and the liquid-rich jet is found above this position. The liquid-jet angle approaches that of the SEN port when the flow becomes structurally coupled. Structurally uncoupled flows report gas jets that follow torrent-type patterns which are well explained using a multiphase fluid-dynamics model. Structurally coupled flows yield gas jets with a continuous pattern.  相似文献   
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84.
The distribution of the protein energy ratio indicators (Pe%), amino acid score and protein value (NDpCal%) in the three daily meals (breakfast, lunch and dinner) of the diet of pregnant women from Santa María Cauqué, Guatemala, was studied. The results were compared with those obtained for the total daily food intake. The differences observed were not significant, confirming the validity of the determination of amino acid score, Pe% and NDpCal% in the foods consumed during the whole day in this type of populations. It also reflects the nutritional benefit of the food pattern, since protein utilization would not be decreased by a different distribution of protein quality and concentration throughout the three daily meals. The variability among individuals of Pe% intake, amino acid score and NDpCal% gave the following values: 16.0, 9.3 and 15.6, respectively. It is noteworthy to add that the variability of Pe% observed is similar to that reported for populations of developed countries.  相似文献   
85.
Increased socioeconomic differences in mortality in eight Spanish provinces   总被引:1,自引:0,他引:1  
In Spain, the study of socioeconomic differences in mortality has been limited by the fact that death certificates often do not include complete information on occupation. In this study, we chose those geographic areas with the highest quality information on occupation of the deceased in order to study socioeconomic differences in mortality from various causes of death. We used information from the death certificates of males who died between 30 and 64 years of age in eight Spanish provinces to compare mortality from the leading causes of death in professionals and managers (group I) and in manual laborers (group II) in 1980-82 and 1988-90. In each period the standardized mortality ratios (SMRs) were higher in group II, except for ischaemic heart disease during the first period, and cancer of the colon and rectum in both, although in the latter case the differences were not statistically significant. The ratio between the SMR from all causes in group II and group I was 1.27 in 1980-82, and 1.72 in 1988-90; for cancer of the colon and rectum the ratio went from 0.98 to 0.84, and for ischaemic heart disease, from 0.80 to 1.31. Except for cancer of the colon and rectum, which resulted in higher mortality in occupational group I, the excess mortality in occupational group II increased between the first and second period. The relation between socioeconomic level and mortality for ischaemic heart disease was reversed, a phenomenon similar to that which took place in the 1960s and 1970s in the developed countries.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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87.
Castanea sativa is an important tree nut species worldwide, highly appreciated for its multifunctional role, in particular for timber and nut production. Nowadays, new strategies are needed to achieve plant resilience to diseases, climate change, higher yields, and nutritional quality. Among the new plant breeding techniques (NPBTs), the CRISPR/Cas9 system represents a powerful tool to improve plant breeding in a short time and inexpensive way. In addition, the CRISPR/Cas9 construct can be delivered into the cells in the form of ribonucleoproteins (RNPs), avoiding the integration of exogenous DNA (GMO-free) through protoplast technology that represents an interesting material for gene editing thanks to the highly permeable membrane to DNA. In the present study, we developed the first protoplast isolation protocol starting from European chestnut somatic embryos. The enzyme solution optimized for cell wall digestion contained 1% cellulase Onozuka R-10 and 0.5% macerozyme R-10. After incubation for 4 h at 25 °C in dark conditions, a yield of 4,500,000 protoplasts/mL was obtained (91% viable). The transfection capacity was evaluated using the GFP marker gene, and the percentage of transfected protoplasts was 51%, 72 h after the transfection event. The direct delivery of the purified RNP was then performed targeting the phytoene desaturase gene. Results revealed the expected target modification by the CRISPR/Cas9 RNP and the efficient protoplast editing.  相似文献   
88.
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma.  相似文献   
89.
Galectin 1 (Gal1) exerts immunomodulatory effects leading to therapeutic effects in autoimmune animal models. Patients with rheumatoid arthritis have been reported to show higher Gal1 serum levels than the healthy population. Our study aimed to find genetic variants on the Gal1 gene (LGALS1) modulating its expression and/or clinical features in patients with early arthritis (EA). LGALS1 was sequenced in 53 EA patients to characterize all genetic variants. Then, we genotyped rs9622682, rs929039, and rs4820293, which covered the main genetic variation in LGALS1, in 532 EA patients. Gal1 and IL-6 serum levels were measured by ELISA and Gal1 also by western blot (WB) in lymphocytes from patients with specific genotypes. Once disease activity improved with treatment, patients with at least one copy of the minor allele in rs9622682 and rs929039 or those with GG genotype in rs4820293 showed significantly higher Gal1 serum levels (p < 0.05). These genotypic combinations were also associated with higher Gal1 expression in lymphocytes by WB and lower IL-6 serum levels in EA patients. In summary, our study suggests that genetic variants studied in LGALS1 can explain heterogeneity in Gal1 serum levels showing that patients with higher Gal1 levels have lower serum IL-6 levels.  相似文献   
90.
The management of chronic liver diseases (CLDs) remains a challenge, and identifying effective treatments is a major unmet medical need. In the current review we focus on the pituitary tumor transforming gene (PTTG1)/delta like non-canonical notch ligand 1 (DLK1) axis as a potential therapeutic target to attenuate the progression of these pathological conditions. PTTG1 is a proto-oncogene involved in proliferation and metabolism. PTTG1 expression has been related to inflammation, angiogenesis, and fibrogenesis in cancer and experimental fibrosis. On the other hand, DLK1 has been identified as one of the most abundantly expressed PTTG1 targets in adipose tissue and has shown to contribute to hepatic fibrosis by promoting the activation of hepatic stellate cells. Here, we extensively analyze the increasing amount of information pointing to the PTTG1/DLK1 signaling pathway as an important player in the regulation of these disturbances. These data prompted us to hypothesize that activation of the PTTG1/DLK1 axis is a key factor upregulating the tissue remodeling mechanisms characteristic of CLDs. Therefore, disruption of this signaling pathway could be useful in the therapeutic management of CLDs.  相似文献   
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