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911.
Children's early approaches to learning and academic trajectories through fifth grade. 总被引:2,自引:0,他引:2
Li-Grining Christine P.; Votruba-Drzal Elizabeth; Maldonado-Carre?o Carolina; Haas Kelly 《Canadian Metallurgical Quarterly》2010,46(5):1062
Children's early approaches to learning (ATL) enhance their adaptation to the demands they experience with the start of formal schooling. The current study uses individual growth modeling to investigate whether children's early ATL, which includes persistence, emotion regulation, and attentiveness, explain individual differences in their academic trajectories during elementary school. Using data from the Early Childhood Longitudinal Study – Kindergarten Cohort (ECLS-K), the present investigation examined the association between ATL at kindergarten entry and trajectories of reading and math achievement across 6 waves of data from kindergarten, 1st, 3rd, and 5th grade (n = 10,666). The current study found a positive link between early ATL and individual trajectories of reading and math performance. Overall, children's early ATL was equally beneficial for children regardless of their race/ethnicity and dimensions of their socioeconomic background. However, links between early ATL and academic trajectories differed by their gender and initial levels of math and reading achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
912.
913.
Carolina Valenzuela Lilian Abugoch Cristian Tapia Alexander Gamboa 《International Journal of Food Science & Technology》2013,48(4):843-849
It is important to produce hydrophobic edible protein films for use in foods. The aim of this study was to evaluate the effect of alkaline extraction of quinoa proteins (QP) on the structure and their film‐forming ability without plasticiser. QP were extracted between pH 8 to 12, and their structure was evaluated by PAGE‐SDS, size‐exclusion HPLC light scattering, fluorescence spectroscopy and SH and SS. Film was characterised by FTIR, SEM, tensile strength, barrier and colour. Structural changes of QP showing that alkalinisation over pH 10 produce significant denaturation/aggregation/dissociation structural changes in QP. pH 12 was the condition to form a film (film12). FTIR showed hydrogen bonds and hydrophobic film interactions. Film12 had 16.6 ± 3.8% elongation and 15.7 ± 1.1 MPa tensile strength, and water vapour permeability was 5.18 ± 0.38 g mm m?2 day?1 kPa?1. Film12 had a brownish colour. A high degree of denaturation/aggregation/dissociation of QP structure is required to form a film without plasticiser. 相似文献
914.
915.
Alexander Trujillo Sourisak Sinbandhit Loïc Toupet David Carrillo Carolina Manzur Jean-René Hamon 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(1):81-99
The synthesis of neutral dinuclear iron–nickel unsymmetrical Schiff base complexes 3 and 4 was achieved via a template reaction involving equimolar amounts of alkyl or aryl “half-unit” precursors, respectively, Fc–C(O)CH=C(CH3)N(H)R (1: R = CH2CH2NH2; 2: R = o-C6H4NH2; Fc = CpFe(η5-C5H4); Cp = η5-C5H5), 5-bromosalicylaldehyde and nickel(II) acetate tetrahydrate in a refluxing CH2Cl2/MeOH (1:1) mixture. The ionic trinuclear unsymmetrical complex 5 was prepared by reacting its dinuclear precursor 3 with the arenophile source, [Cp*Ru(NCCH3)3]PF6 (Cp* = η5-C5(CH3)5), in refluxing CH2Cl2 for 2 h, whereas the trinuclear species 6 was formed upon regioselective π-complexation of the 5-bromosalicylidene ring of 4 by [Cp*Ru]+ at room temperature overnight. All the new compounds were adequately characterized by analytical and spectroscopic techniques
and, in addition, the crystal and molecular structures of the “half-unit” 1, the binuclear complex 4 and its hemisolvate adduct 4 · 0.5CH3OH, the trinuclear Schiff base compound 5 · 2(CH3)2CO, and the mixed sandwich metalloligand 7 have been determined by X-ray crystallography. Both organometallic–inorganic hybrids 5 and 6 contain the neutral electron-releasing ferrocenyl group, and the cationic electron-withdrawing ruthenium mixed sandwich,
linked through the unsymmetrical tetradentate Schiff base complex {Ni(ONNO)}. UV–vis, 1H and 13C NMR as well as electrochemical data clearly indicate a mutual donor–acceptor electronic influence between the organometallic
termini. Furthermore, X-ray crystal structure analysis of 5 · 2(CH3)2CO reveals the partial delocalization of bonding electron density throughout the dinucleating nickel Schiff base ligand.
Dedicated to Prof. Didier Astruc, a true friend, an outstanding lecturer and scientist, in honor of his pioneering research
efforts and accomplishments in the fields of organometallic chemistry, dendrimers and their applications in nanocatalysis. 相似文献
916.
Schnettler B Shene C Rubilar M Miranda H Sepúlveda J Denegri M Lobos G 《Archivos latinoamericanos de nutrición》2010,60(4):380-390
In view of the interest in the role of foodstuffs in improving wellbeing and health, the object of this study is to distinguish consumer typologies in Temuco, La Araucanía Region, Chile, according to their preferences for different functional ingredients, flavouring, colouring and price in yoghurt. A semi-structured survey was applied to 400 supermarket customers. The respondents ordered eight alternative yoghurts according to their preferences, with different functional ingredients (fibre, antioxidants), flavourings (sugar, sweetener), colouring (natural, artificial) and three price options, for a conjoint analysis with fractional factorial design. Variables affecting knowledge of "functional food" were evaluated using a binomial logit model. It was determined by conjoint analysis that in general a preference existed for yoghurt containing fibre, sweetener, natural colouring, and at the lowest price. Three typologies were distinguished by analysis of hierarchical conglomerates: the majority segment (48.8%) displayed a greater preference for fibre; the second (41.7%) also preferred fibre, but gave first priority to artificial colouring and preferred a higher price. The minority (9.5%) was the only segment to prefer antioxidants. The typologies differed significantly in satisfaction with their food-related life, knowledge of the function of fibre and presence of cancer and obesity in some member of the respondent's family. The binomial logit model was significant (P < 0.01), indicating that if the consumer has a job or has had access to information on functional foods, the probability increased of knowledge of what these mean. There was thus majority acceptance of yoghurt enriched with fibre and with added sweetener. 相似文献
917.
The typology, number, size, and distribution pattern of labellar and palpal sensilla of male and female Lutzomyia longipalpis (Lutz and Neiva, 1912) sand flies were analyzed by scanning electron and light microscopy, contributing to the construction of a gustatory and olfactory map in this important vector species. About 35 trichoid sensilla, sorted into three different classes according to their lengths, are present on the two labellar lobes. Five distinct structures are observed in the maxillary palps, which could be classified as noninnervated (microtrichia and scales) or the following innervated structures: 1) campaniform sensilla, found near the distal end of palpal segments II and III; 2) multiporous capitate peg sensilla, found in reduced number (1-6) on segment II, but located in a group of 15-25 on the distal third part of segment III; and 3) trichoid sensilla, distributed linearly on segment IV and spirally on segment V. Light microscopy analysis of silver-stained specimens indicated the presence of pores in the trichoid sensilla and their chemosensory function is discussed, as well as the possible function of the other sensilla. 相似文献
918.
Andrea Palicelli Stefania Croci Alessandra Bisagni Eleonora Zanetti Dario De Biase Beatrice Melli Francesca Sanguedolce Moira Ragazzi Magda Zanelli Alcides Chaux Sofia Caete-Portillo Maria Paola Bonasoni Alessandra Soriano Stefano Ascani Maurizio Zizzo Carolina Castro Ruiz Antonio De Leo Guido Giordano Matteo Landriscina Giuseppe Carrieri Luigi Cormio Daniel M. Berney Jatin Gandhi Valerio Copelli Giuditta Bernardelli Giacomo Santandrea Martina Bonacini 《International journal of molecular sciences》2021,22(22)
The tumor microenvironment (TME) includes immune (T, B, NK, dendritic), stromal, mesenchymal, endothelial, adipocytic cells, extracellular matrix, and cytokines/chemokines/soluble factors regulating various intracellular signaling pathways (ISP) in tumor cells. TME influences the survival/progression of prostate cancer (PC), enabling tumor cell immune-evasion also through the activation of the PD-1/PD-L1 axis. We have performed a systematic literature review according to the PRISMA guidelines, to investigate how the PD-1/PD-L1 pathway is influenced by TME and ISPs. Tumor immune-escape mechanisms include suppression/exhaustion of tumor infiltrating cytotoxic T lymphocytes, inhibition of tumor suppressive NK cells, increase in immune-suppressive immune cells (regulatory T, M2 macrophagic, myeloid-derived suppressor, dendritic, stromal, and adipocytic cells). IFN-γ (the most investigated factor), TGF-β, TNF-α, IL-6, IL-17, IL-15, IL-27, complement factor C5a, and other soluble molecules secreted by TME components (and sometimes increased in patients’ serum), as well as and hypoxia, influenced the regulation of PD-L1. Experimental studies using human and mouse PC cell lines (derived from either androgen-sensitive or androgen-resistant tumors) revealed that the intracellular ERK/MEK, Akt-mTOR, NF-kB, WNT and JAK/STAT pathways were involved in PD-L1 upregulation in PC. Blocking the PD-1/PD-L1 signaling by using immunotherapy drugs can prevent tumor immune-escape, increasing the anti-tumor activity of immune cells. 相似文献
919.
920.
Daniel N. Silva Elisabete C. Costa Carolina F. Rodrigues Duarte de Melo-Diogo Ilídio J. Correia Andr F. Moreira 《International journal of molecular sciences》2021,22(1)
3D tumor spheroids have arisen in the last years as potent tools for the in vitro screening of novel anticancer therapeutics. Nevertheless, to increase the reproducibility and predictability of the data originated from the spheroids it is still necessary to develop or optimize the techniques used for spheroids’ physical and biomolecular characterization. Fluorescence microscopy, such as confocal laser scanning microscopy (CLSM), is a tool commonly used by researchers to characterize spheroids structure and the antitumoral effect of novel therapeutics. However, its application in spheroids’ analysis is hindered by the limited light penetration in thick samples. For this purpose, optical clearing solutions have been explored to increase the spheroids’ transparency by reducing the light scattering. In this study, the influence of agitation conditions (i.e., static, horizontal agitation, and rotatory agitation) on the ClearT and ClearT2 methods’ clearing efficacy and tumor spheroids’ imaging by CLSM was characterized. The obtained results demonstrate that the ClearT method results in the improved imaging of the spheroids interior, whereas the ClearT2 resulted in an increased propidium iodide mean fluorescence intensity as well as a higher signal depth in the Z-axis. Additionally, for both methods, the best clearing results were obtained for the spheroids treated under the rotatory agitation. In general, this work provides new insights on the ClearT and ClearT2 clearing methodologies and their utilization for improving the reproducibility of the data obtained through the CLSM, such as the analysis of the cell death in response to therapeutics administration. 相似文献