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61.
Philip Andrew Helliwell Victoria Adele Bailey Caroline Chevet Don Brian Clarke Antony Lloyd Roy Macarthur Anne Routledge 《Reactive and Functional Polymers》2010,70(2):110-115
Deuterated N-ethylpiperidine hypophosphite (d-EPHP) and tributyltin deuteride (TBTD) have been used to explore potential microenvironmental effects in resin-bound radical propagation. A deuterium labelling mass spectrometric method was used to show that efficiency of radical chain propagation on resin can be influenced by the choice of solid-support when using the slow radical chain carrier, EPHP. 相似文献
62.
Carmelo Ardito Paolo Buono Maria Francesca Costabile Rosa Lanzilotti Antonio Piccinno 《Journal of Visual Languages and Computing》2012,23(2):78-90
In our Age of exponential technological advance, recent developments are determining an evolution of end users from passive information consumers into information producers. Users are increasingly willing and, indeed, determined to shape the software they use to tailor it to their own needs. Based on a brief review of research activities we performed in the last decade, this paper analyzes some challenges that software designers face to comply with the new roles of end users in the software life cycle, and discusses how to provide end users with software environments that empower them to become co-designers of their own tools and products. The examples reported in the paper show why and how end users are involved in design activities in various application domains. 相似文献
63.
Federica Di Costanzo Valeria Di Dato Leonardo Joaquim van Zyl Adele Cutignano Francesco Esposito Marla Trindade Giovanna Romano 《International journal of molecular sciences》2021,22(24)
Diatoms are a successful group of microalgae at the base of the marine food web. For hundreds of millions of years, they have shared common habitats with bacteria, which favored the onset of interactions at different levels, potentially driving the synthesis of biologically active molecules. To unveil their presence, we sequenced the genomes of bacteria associated with the centric diatom Thalassiosira rotula from the Gulf of Naples. Annotation of the metagenome and its analysis allowed the reconstruction of three bacterial genomes that belong to currently undescribed species. Their investigation showed the existence of novel gene clusters coding for new polyketide molecules, antibiotics, antibiotic-resistance genes and an ectoine production pathway. Real-time PCR was used to investigate the association of these bacteria with three different diatom clones and revealed their preference for T. rotula FE80 and Skeletonema marinoi FE7, but not S. marinoi FE60 from the North Adriatic Sea. Additionally, we demonstrate that although all three bacteria could be detected in the culture supernatant (free-living), their number is up to 45 times higher in the cell associated fraction, suggesting a close association between these bacteria and their host. We demonstrate that axenic cultures of T. rotula are unable to grow in medium with low salinity (<28 ppt NaCl) whereas xenic cultures can tolerate up to 40 ppt NaCl with concomitant ectoine production, likely by the associated bacteria. 相似文献
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66.
Hayes Adele M.; Feldman Greg C.; Beevers Christopher G.; Laurenceau Jean-Philippe; Cardaciotto LeeAnn; Lewis-Smith Jamie 《Canadian Metallurgical Quarterly》2007,75(3):409
Significant shifts or discontinuities in symptom course can mark points of transition and reveal important change processes. The authors investigated 2 patterns of change in depression-the rapid early response and a transient period of apparent worsening that the authors call a depression spike. Participants were 29 patients diagnosed with major depressive disorder who enrolled in an open trial of an exposure-based cognitive therapy. Hierarchical linear modeling revealed an overall cubic shape of symptom change and that both the rapid response and spike patterns predicted lower posttreatment depression. Patients wrote weekly narratives about their depression. Early narratives of rapid responders were coded as having more hope than those of nonrapid responders. The narratives of patients with a depression spike had more cognitive-emotional processing during this period of arousal than those without a spike. Findings are discussed in the context of cognitive-emotional processing theories in depression and anxiety disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
For each of 2 sex-balanced groups of 3.5-mo-old infants (N = 24), illumination of a black and white slide with either a 2 * 2 or a 24 * 24 checkerboard pattern was made directly proportional to the momentary rate of nonnutritive sucks greater than a predetermined criterion. A noncontingent baseline period of responding was followed by several minutes of conjugate sucking. Sucking performance was assessed by (a) the number of minutes to reach the decrement criterion (satiation time), (b) the rate of criterion sucking, and (c) the proportion of sucks which exceeded the amplitude criterion. Results indicate that check density did not differentially affect the sucking performance on any of the measures; sex of the S was significantly related to performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Infrared spectroscopic imaging with 6-10 microm spatial resolution was used to characterize the changes in fracture callus mineral content, carbonate content, mineral crystallinity, and collagen maturity in femurs of 3-month-old ovariectomized rats treated with estrogen (estrogen sufficiency) or vehicle (estrogen deficiency). Comparisons were also made in these animals to cortical bone at a distance from the callus. Analyses at 4, 8, and 12 weeks post fracture demonstrated that healing was accelerated in the estrogen-sufficient animals as demonstrated by increasing mineral content and collagen maturity and decreasing carbonate incorporation. 相似文献
69.
Reale L Lai A Tucci A Poma A Faenov A Pikuz T Flora F Spano L Limongi T Palladino L Ritucci A Tomassetti G Petrocelli G Francucci M Martellucci S 《Microscopy research and technique》2004,64(1):21-29
A method for detecting cadmium uptake in leaves of Saponaria officinalis doped with a solution of cadmium acetate is described. The technique based on the exposure of dried leaves to X-rays of a wavelength close to that of the metal K-edge could be useful for phytoremediation studies as it could reveal the bioaccumulation in plants due to the treatment either in vivo or in vitro with heavy metals. X-ray microradiography measurements are in agreement with those from peroxidase enzyme assay utilized to follow the oxidative damage induced by heavy metals. At present, as we will see in this report, microradiography has still poorer sensitivity in comparison with enzyme assay, but it has the advantage of being faster, not destructive, and usable even at very high doping levels, where the enzyme assay technique results are fully saturated. Further analysis of the optical density values could lead to a quantitative measurement of the heavy metal in the sample. Thus, the technology developed in this article could be useful for tracing the intake in phytoremediation studies. 相似文献
70.
Breast cancer is the main cause of morbidity and mortality in women worldwide. However, the molecular pathogenesis of breast cancer remains poorly defined due to its heterogeneity. Several studies have reported that G Protein-Coupled Estrogen Receptor 1 (GPER1) plays a crucial role in breast cancer progression, by binding to estrogens or synthetic agonists, like G-1, thus modulating genes involved in diverse biological events, such as cell proliferation, migration, apoptosis, and metastasis. In addition, it has been established that the dysregulation of short sequences of non-coding RNA, named microRNAs (miRNAs), is involved in various pathophysiological conditions, including breast cancer. Recent evidence has indicated that estrogens may regulate miRNA expression and therefore modulate the levels of their target genes, not only through the classical estrogen receptors (ERs), but also activating GPER1 signalling, hence suggesting an alternative molecular pathway involved in breast tumor progression. Here, the current knowledge about GPER1 and miRNA action in breast cancer is recapitulated, reporting recent evidence on the liaison of these two players in triggering breast tumorogenic effects. Elucidating the role of GPER1 and miRNAs in breast cancer might provide new tools for innovative approaches in anti-cancer therapy. 相似文献