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排序方式: 共有340条查询结果,搜索用时 15 毫秒
331.
332.
‘A Fantasy to Get Employment Around the Area’: Long Commutes and Resident Health in an Outer Urban Master-Planned Estate 总被引:1,自引:0,他引:1
The Selandra Rise master-planned estate (MPE) in Melbourne’s south-east growth corridor was designed to create a “healthy and engaged community” through the provision of parks, physical activity opportunities and community facilities. A 5 year longitudinal study researched the impact on residents. Over one third of residents spent 2 to 3 h per day commuting and high levels of dissatisfaction with commutes were found. Longer commute times were associated with poor physical activity and weight outcomes. The paper concludes that provisions for health and wellbeing within an MPE are insufficient when opportunities for local employment are limited and broader locational, connectivity and transport disadvantages are not addressed. 相似文献
333.
Jessica Olvera-Mancilla Salvador López-Morales Joaquín Palacios-Alquisira David Morales-Morales Ronan Le Lagadec Larissa Alexandrova 《Polymer》2014
Polymerization of vinyl acetate (VAc) was carried out with four different cyclometalated ruthenium(II) catalysts, using CCl4 as initiator under conventional heating and microwave irradiation. The thermo-polymerizations were solvent-dependent and proceeded to limited conversions without control. Only the polymerization in DMSO mediated by [Ru(η6-C6H6)(C6H4-2-CH2NMe2)(MeCN)]PF6 (1) showed dependence of the molecular weights on conversion. Besides, this complex was the only one active under microwave irradiation. The microwave assisted polymerization was much faster than that under conventional heating, maintaining an increase of the molecular weights with conversion. The chain extensions were quite successful under both conventional heating and microwave irradiation, confirming the participation of ATRP mechanism. The complex 1 was active in atom transfer radical addition of CCl3Br to VAc substrate providing the adduct in high yield. Mechanistic studies demonstrated the importance of the presence of a labile benzene ligand to increase the catalytic activity of the ruthenium complexes. 相似文献
334.
Larissa Hering Egle Katkeviciute Marlene Schwarzfischer Anna Niechcial Julianne B. Riggs Marcin Wawrzyniak Kirstin Atrott Marnix van de Sande Silvia Lang Burkhard Becher Gerhard Rogler Michael Scharl Marianne R. Spalinger 《International journal of molecular sciences》2021,22(13)
Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) plays a critical role in the pathogenesis of inflammatory bowel diseases (IBD). Mice lacking PTPN2 in dendritic cells (DCs) develop skin and liver inflammation by the age of 22 weeks due to a generalized loss of tolerance leading to uncontrolled immune responses. The effect of DC-specific PTPN2 loss on intestinal health, however, is unknown. The aim of this study was to investigate the DC-specific role of PTPN2 in the intestine during colitis development. PTPN2fl/flxCD11cCre mice were subjected to acute and chronic DSS colitis as well as T cell transfer colitis. Lamina propria immune cell populations were analyzed using flow cytometry. DC-specific PTPN2 deletion promoted infiltration of B and T lymphocytes, macrophages, and DCs into the lamina propria of unchallenged mice and elevated Th1 abundance during acute DSS colitis, suggesting an important role for PTPN2 in DCs in maintaining intestinal immune cell homeostasis. Surprisingly, those immune cell alterations did not translate into increased colitis susceptibility in acute and chronic DSS-induced colitis or T cell transfer colitis models. However, macrophage depletion by clodronate caused enhanced colitis severity in mice with a DC-specific loss of PTPN2. Loss of PTPN2 in DCs affects the composition of lamina propria lymphocytes, resulting in increased infiltration of innate and adaptive immune cells. However, this did not result in an elevated colitis phenotype, likely because increased infiltration of macrophages in the intestine upon loss of PTPN2 loss in DCs can compensate for the inflammatory effect of PTPN2-deficient DCs. 相似文献
335.
Grawitch Matthew J.; Granda Stephanie E.; Barber Larissa K. 《Canadian Metallurgical Quarterly》2008,13(4):331
The current study uses self-regulation as the basis for a model that examines the influence of three types of workday appraisals (resource, task, and response). At the beginning of their workday, a total of 170 faculty, graduate students, and staff of a university completed appraisal ratings of their anticipated workday tasks, resources, and responses. At the end of the workday, they completed assessments of positive and negative affect and self-monitored performance. Results suggested that resource appraisals of control and skills were predictive of task appraisals of difficulty, threat, and ambiguity. Task appraisals were then predictive of both response appraisals, in terms of anticipated support and effort, and self-monitored performance at the end of the day. Anticipated effort and self-monitored performance were both positively related to positive affect at the end of the day. Anticipated support and self-monitored performance were both negatively related to negative affect at the end of the day, while threat task appraisals were positively related to negative affect. Implications of the results for workplace interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
336.
Larissa Klaß Andreas Wilden Fabian Kreft Christoph Wagner Andreas Geist Petra J. Panak 《溶剂提取与离子交换》2013,31(5):297-312
ABSTRACTN,N,N’,N’-tetraethyldiglycolamide (TEDGA) is used in the French EXAm (extraction of americium) process to separate Am(III) from Cm(III) and Ln(III). In this study, the complexation behavior of TEDGA towards actinides(III) and lanthanides(III) was compared to its methyl-substituted derivatives Me-TEDGA and Me2-TEDGA under experimental conditions applying to the EXAm process. Using the EXAm solvent, 0.6 mol/L N,N’-dimethyl-N,N’-dioctyl-hexylethoxymalonamide (DMDOHEMA) and 0.45 mol/L bis(2-ethylhexyl)-phosphoric acid (HDEHP), An(III) and Ln(III) distribution ratios increase in the order TEDGA < Me-TEDGA < Me2-TEDGA. This is explained by differences in the strength of complexation in the aqueous phase: Conditional stability constants for the formation of [Cm(DGA)x]3+ complexes decrease in the order TEDGA > Me-TEDGA > Me2-TEDGA, as shown by time-resolved laser fluorescence spectroscopy (TRLFS). TRLFS measurements verified the exclusive existence of [Cm(DGA)3]3+ complexes in the aqueous phase. Both the homoleptic [Cm(DMDOHEMA)n]3+ and the heteroleptic [Cm(DGA)x(DMDOHEMA)y]3+ complexes were detected in the organic phase, as postulated in the literature.[14] 相似文献
337.
Julien Lumeau Larissa Glebova Valerii Golubkov Edgar D. Zanotto Leonid B. Glebov 《Optical Materials》2009,32(1):139-146
Photo-thermo-refractive (PTR) glass is a multi-component silicate that undergoes localized refractive index decrease after UV-exposure and thermal treatment for partial crystallization. Based on this refractive index change, high efficiency volume Bragg gratings have been developed in PTR glass and have been successfully used for laser beam control. However, despite the fact that this type of glass has been widely studied and used over the last 20 years, the origin of the refractive index change upon crystallization is poorly understood. In this paper, we introduce three possible mechanisms (the precipitation of nano-sized NaF crystals and the associated local chemical changes of the glass matrix, the volumetric changes due to relaxation, and the local residual stresses) for the refractive index decrement in PTR glass and estimate the partial refractive index change due to each mechanism. Refractive index measurements are compared with high temperature XRD experiments and a general approach for the simulation of the refractive index change in PTR glass is proposed. We show that among the studied variables the residual stresses surrounding the crystals are the main responsible for the local refractive index decrement in this glass. 相似文献
338.
Marcos Marques da Silva Paula César Vitório Franco Mario César Baldin Larissa Rodrigues Tatiana Barichello Geovana Dagostim Savi Luiz Felipe Bellato Márcio Antônio Fiori Luciano da Silva 《Materials science & engineering. C, Materials for biological applications》2009,29(2):647-650
This work reports the preparation and characterization of copolymer poly-{styrene-acrylic acid} with monomeric ratio of styrene/acrylic acid of 9:1 using benzoyl peroxide as initiator and furthermore filled with nanosilver (25 ppm and 50 ppm) in water/acetone (1:40 v/v). The nanosilver emulsion was obtained from chemical reduction using NaBH4 as reducing agent and sodium citrate as the stabilizer. The preparation of nanosilver emulsion was monitored by the appearance of a Plasmon Resonant Absorption band in a UV–visible spectrophotometer and the particles sizes were observed through TEM. Microbiological studies were performed to investigate the antimicrobial activity of this new material against the microorganisms Escherichia coli (ATCC-25922) and Staphylococcus aureus (ATCC-6538), used as reference strains. The antimicrobial activity of the poly-{styrene-acrylic acid} filled with nanosilver was confirmed by the presence of an inhibition halo of the bacterial growth in seeded culture media, but was not found with the poly(styrene-acrylic acid) alone. The present work suggests that silver ions are released from the polymeric matrix to the culture media and have the ability to tune the Ag+ ions released by controlling the amount of Ag nanoparticles embedded in the composite. 相似文献
339.
Development and characterization of wheat gluten microspheres for use in a controlled release system
Larissa Andreani Rodrigo Cercená Betina G.Z. Ramos Valdir Soldi 《Materials science & engineering. C, Materials for biological applications》2009,29(2):524-531
The purpose of this study was the development and characterization of wheat gluten microspheres for use as controlled release devices, and the evaluation of the effect of the addition of poly (ethylene glycol) (PEG). Diltiazem hydrochloride was used as the model drug in the in vitro release essay. The physical–chemical and morphological properties of the microspheres were evaluated, as well as their encapsulation efficiency. Porosity varied with the presence or absence of PEG. The diltiazem encapsulation efficiency was 72.8% and 96.7% for wheat gluten and gluten/PEG 95/05 microspheres, respectively. The DSC and FTIR results indicated interactions between the microparticles and additives used. In the in vitro release tests it was observed that, for all the studied systems, the burst effect occurred in the first 2 h of release and the microspheres prepared with PEG had a faster release rate. In the attempt to elucidate the release mechanism, the systems were treated based on two well known mathematical models: the Higuchi and the power law. It was found that the microsphere release mechanism is not exclusively diffusion-controlled and, probably, the release occurs through a combination of partial diffusion through the swelling matrix and hydrophilic pores. 相似文献
340.
A new approach for design of organic electrochromic devices with inter-digitated electrode structure
Galit Bar Galit Strum Raz Gvishi Nina Larina Vladimir Lokshin Vladimir Khodorkovsky Larissa Grinis Arie Zaban Irina Kiryuschev 《Solar Energy Materials & Solar Cells》2009,93(12):2118-8
We present a new approach for design of organic electrochromic devices (ECD) with inter-digitated electrode (IDE) structure and three-electrode dynamic operation. The advantages of the IDE design include the ability to produce fast and homogenous color change over large areas. In addition, it enables fabrication of multi-color devices. Our method involves photolithographic etching of ITO followed by electrophoretic deposition (EPD) and mechanical compression of porous titania to produce finely patterned electrodes with high surface area. The titania layer is chemically modified by new stable and reversible electrochromic viologen derivatives involving phenylphosphonic acid anchoring moiety. The new device demonstrates reversible and strong color change from colorless to deep blue and yellow. 相似文献