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Preschoolâaged children are aware of differences in the race and abilities of the people around them. Given this awareness it is important to promote children's acceptance of diversity in the preschool period. The goals of th...
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Preschoolâaged children are aware of differences in the race and abilities of the people around them. Given this awareness it is important to promote children's acceptance of diversity in the preschool period. The goals of this study were to assess the extent to which child care centres provide diversity instruction through classroom activities, materials and displays. The extent to which structural quality characteristics (e.g. staff training and education) contribute to diversityâpositive classrooms was also examined. Data were collected from 103 preschool classrooms in 64 child care centres serving a population of ethnically diverse families in Toronto, Canada. On average, these classrooms were found to be diversityâpositive environments. Hierarchical linear model analyses indicate that utilising a variety of teaching formats, higher salaries, greater supervision and having higher proportions of children who receive a child care subsidy predicted higher scores on a diversity instruction and materials index. This index was largely based on classroom observations. In contrast, lower levels of education and salary predicted staff reports of diversityâpromoting activities. These latter counterâintuitive results are interpreted in light of potential selfâpresentation biases.View full textDownload full textKeywordsdiversity, diversity instruction, child care instruction, ethnic diversity, ability diversity, preschool instructionRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/03004430802287606
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2-(2',5'-Dihydroxy-phenyl)-4(3H)-quinazolinone (DHPQ), a new fluorescent dye that exhibits excited state intramolecular proton transfer (ESIPT) reaction and possesses good photophysical properties, is synthesised and used as fluor...
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2-(2',5'-Dihydroxy-phenyl)-4(3H)-quinazolinone (DHPQ), a new fluorescent dye that exhibits excited state intramolecular proton transfer (ESIPT) reaction and possesses good photophysical properties, is synthesised and used as fluorescent probe for detection of Hg~(2+). Mercuric ions can, be detected and quantitated by measuring the fluorescent intensity decrease of the probe. The decrease of fluorescence intensity of DHPQ upon the addition of Hg~(2+) was attributed to the blocking of ESIPT reactions of DHPQ and quenching its fluorescence. The analytical performance characteristics of the proposed Hg~(2+) probe were investigated. The probe can be applied to the quantification of Hg~(2+) with a concentration range covering from 8.0×10~(-7) to 2.0 × 10~(-4)molL~(-1), with a working pH range of 5.5-6.5. It shows excellent selectivity for Hg~(2+) over other transition metal cations. The proposed method was testified for the Hg~(2+) assay in river water samples with satisfying recoveries.
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The Ni―B amorphous alloy in the form of ultrafine particles was prepared by chemical reduction with BH_4~- in aqueous solution. In comparison with other Ni-based catalysts, such as the ultrafine Ni powder prepared by NH2NH2 reduc...
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The Ni―B amorphous alloy in the form of ultrafine particles was prepared by chemical reduction with BH_4~- in aqueous solution. In comparison with other Ni-based catalysts, such as the ultrafine Ni powder prepared by NH2NH2 reduction and Raney Ni catalyst used commonly in the industrial nitrile hydrogenation, the as-prepared Ni―B catalyst exhibited higher activity and better selectivity to ethylamine during the liquid phase hydrogenation of acetonitrile. Under the present reaction conditions, the maximum yield of ethylamine over the Ni―B amorphous alloy reached 67.6%, much higher than that over Raney Ni ( < 40%). Kinetic studies revealed that the acetonitrile hydrogenation was first-order with respect to hydrogen pressure and zero-order with respect to acetonitrile concentration. However, at extremely low acetonitrile concentration, the hydrogenation rate increased linearly with the increase of acetonitrile concentration. Pretreatment of the Ni―B amorphous alloy at elevated temperature resulted in an abrupt decrease in both the hydrogenation rate and the selectivity to ethylamine due to the crystallization. According to various characterizations, such as selective area electronic diffraction (SAED), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), extended X-ray absorption fine structure (EXAFS), X-ray photoelectron spectroscopy (XPS), differential scanning calorimeter (DSC), and hydrogen chemisorption, etc., the superior performance of the Ni―B amorphous alloy on other Ni-based catalysts was discussed by considering both the structural effect and the electronic effect as well as the mechanism of nitrile hydrogenation.
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We investigate theoretically radio-frequency spectroscopy of weakly bound molecules in an ultracold spinorbit-
coupled atomic Fermi gas.We consider two cases with either equal Rashba andDresselhaus coupling or pure
Rashba coupling...
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We investigate theoretically radio-frequency spectroscopy of weakly bound molecules in an ultracold spinorbit-
coupled atomic Fermi gas.We consider two cases with either equal Rashba andDresselhaus coupling or pure
Rashba coupling. The former system has been realized very recently at Shanxi University [Wang et al., Phys. Rev.
Lett. 109, 095301 (2012)] andMIT[Cheuk et al., Phys. Rev. Lett. 109, 095302 (2012)].We predict realistic radiofrequency
signals for revealing the unique properties of anisotropic molecules formed by spin-orbit coupling.
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We used a minirhizotron system to investigate the influence of three major factors—root morphology, root depth, and season of root emergence—on root survivorship and longevity in a Kobresia humilis meadow on the Tibetan Plateau ...
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We used a minirhizotron system to investigate the influence of three major factors—root morphology, root depth, and season of root emergence—on root survivorship and longevity in a Kobresia humilis meadow on the Tibetan Plateau during the growing season of 2009. Root longevity was assessed by survival analysis, Kaplan-Meier analysis, and Cox proportional hazards regression. Root longevity was correlated positively with root diameter. A 17.5 % decrease in the risk of mortality was associated with a 0.1-mm increase in diameter. Roots distributed in the top 10 cm of the soil had significantly shorter longevities than roots at greater depths, with a 48 % decrease of mortality risk for each 10-cm increase in soil depth from the surface to 40 cm. Of all the factors examined, the season of root emergence had the strongest effect on root lifespan. Roots that emerged in May and June had shorter longevity than roots that emerged later in the year, and roots that emerged in September and October were more likely to survive over winter. Our findings indicated that life-history traits of roots in K. humilis meadows are highly heterogeneous, and this heterogeneity should be considered when modeling the contribution of roots to carbon and nitrogen fluxes in this type of meadow ecosystem. Moreover, temporal, spatial, and compositional variations in root longevity must be considered.
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In this paper, we present a coherent feedback control scheme for non-Markovian bosonic systems, in which
an engineered quantum control field is introduced to couple both the system and the noise bath. The closed-loop
dynamics of t...
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In this paper, we present a coherent feedback control scheme for non-Markovian bosonic systems, in which
an engineered quantum control field is introduced to couple both the system and the noise bath. The closed-loop
dynamics of the system is described by an exact non-Markovian quantum Langevin equation, where the spectral
density functions of the noise and the quantum control field, as well as their coupling, are combined into a single
memory kernel function. We show that the coupling between the quantum control field with the noise bath can
be used as a feedback control to modulate the memory kernel function. As a result, the noise bath can be driven
out of resonance with the system and the decoherence can be efficiently suppressed. The effectiveness of the
controllability is demonstrated with a photonic circuit in photonic crystals.
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A component-oriented software system, i.BioMech (image-based biomechanical modeling) is proposed for generation of patient-specific finite element model. It applies a systematic software engineering approach to patient/subject-spe...
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A component-oriented software system, i.BioMech (image-based biomechanical modeling) is proposed for generation of patient-specific finite element model. It applies a systematic software engineering approach to patient/subject-specific meshing and assignment of material properties. The prototype program is based on the component object model (COM), which enables ease of combination of existing mesh generation algorithms and material property assignment schemes, and incorporation of new ones. It also facilitates utilization by other programming languages or platforms. Data input comprises a series of medical images captured from the patient. The output is a patient-specific finite element model for computational analysis using commercially available finite element software. The prototype software system provides a framework to compare the different finite element mesh generation methods as well as schemes for material property assignment. Our focus is on patient/subject-specific modeling of the human vertebrae.
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Increasingly complex life forms were found in older biological soil crusts in the Gurbantaunggut Desert in Northwestern China. These crusts may play a critical role in mineral erosion and desert soil formation by modifying the wea...
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Increasingly complex life forms were found in older biological soil crusts in the Gurbantaunggut Desert in Northwestern China. These crusts may play a critical role in mineral erosion and desert soil formation by modifying the weathering environment and ultimately affecting mineralogical variance. To test this hypothesis, variations in the morphological features and mineralogical components of successional biological soil crusts at 1 cm were studied by optical microscopy, SEM and grain size analysis. Concentrations of erosion-resistant minerals decreased with crust succession, while minerals susceptible to weathering increased with crust development. Neogenetic minerals were found in late stage crusts, but not in early stage crusts. Silt and clay concentrations were highest in early formation crusts and soil mean particle size decreased with crust succession. Cyanobacteria, lichen and moss were shown to erode and etch rocks, and secondary minerals produced by
weathering were localized with the living organisms. Thus, more developed crusts appeared to contribute to greater mineral weathering and may be a major cause of mineralogical variance seen in the Gurbantunggut Desert. The greater activity and complexity of older crusts, as well as their improved moisture condition may function to accelerate mineral weathering. Therefore, protection and recovery of biological crusts is vital for desert soil formation.
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We report two new heteroleptic polypyridyl ruthenium complexes, coded C101 and C102, with high molar extinction coefficients by extending the jr-conjugation of spectator ligands, with a motivation to enhance the optical absorptivi...
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We report two new heteroleptic polypyridyl ruthenium complexes, coded C101 and C102, with high molar extinction coefficients by extending the jr-conjugation of spectator ligands, with a motivation to enhance the optical absorptivity of mesoporous titania film and charge collection yield in a dye-sensitized solar cell. On the basis of this C101 sensitizer, several DSC benchmarks measured under the air mass 1.5 global sunlight have been reached. Along with an acetonitrile-based electrolyte, the C101 sensitizer has already achieved a strikingly high efficiency of 11.0-11.3%, even under a preliminary testing. More importantly, based on a low volatility 3-methoxypropionitrile electrolyte and a solvent-free ionic liquid electrolyte, cells have corresponding > 9.0% and ～7.4% efficiencies retained over 95% of their initial performances after 1000 h full sunlight soaking at 60 ℃. With the aid of electrical impedance measurements, we further disclose that, compared to the cell with an acetonitrile-based electrolyte, a dye-sensitized solar cell with an ionic liquid electrolyte shows a feature of much shorter effective electron diffusion lengths due to the lower electron diffusion coefficients and shorter electron lifetimes in the mesoporous titania film, explaining the photocurrent difference between these two type devices. This highlights the next necessary efforts to further improve the efficiency of cells with ionic liquid electrolytes, facilitating the large-scale production and application of flexible thin film mesoscopic solar cells.
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The tissue optical clearing technique shows great potential in optical diagnosis and therapy. However, short-term and long-term effects of optical clearing agents on blood vessels, which are relevant to the safety of clinical appl...
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The tissue optical clearing technique shows great potential in optical diagnosis and therapy. However, short-term and long-term effects of optical clearing agents on blood vessels, which are relevant to the safety of clinical applications, have not been clarified. We used laser speckle contrast imaging to monitor the changes in blood vessels in chick chorioallantoic membrane (CAM) after application of glyc-erol or glucose. The changes in morphology of vessels and blood flow velocity were measured. Long-term effects on blood vessels were investigated by observing the function and the development of blood vessels. The results show that glycerol reduces the local blood flow velocity and constricts and even blocks vessels quickly. At 2 days, the blood flow velocity is recovered to different extents, and new blood vessels develop but are fewer in number. Glucose induces slow changes in blood flow or vessels. However, most blood vessels are blocked, and no new blood vessel develops at 2 days. The effects depend on the dosage of agents, including volume and concentration, and decrease with the dosage of agents. Therefore, short-term effects of glucose on blood vessels are slighter than those of glycerol, but
long-term effects of glucose are greater.
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