Measuring morningness–eveningness is an important aspect of individual differences because it is associated with many aspects of personality and health. The present study outlines recent advancements in the field of measurement and proposes an improved assessment of morningness–eveningness, such as the measurement of circadian amplitude, updating and reflecting new item developments, addressing the clock time based measures, the morning-biased items and the aspect of uni versus multidimensionality. Four studies have been carried out in Germany to present a novel development (with a total sample of N = 1181). In study I, the exploratory factor analysis (EFA) revealed three dimensions, one of morningness, one of eveningness and one of amplitude/stability. Then, items were reduced to present a clearer factor structure by removing ambiguous items. In the second study, a shortened questionnaire was applied, with 15 items (5 per construct), but Confirmatory Factor Analysis (CFA) did not provide acceptable fit indices. Refining items were made in study III, which again showed a clearer factor structure in EFA, and subsequently, in study IV, the refined set of 15 items provided a good fit of a CFA. The final questionnaire was tested for validity by applying clock times, personality questions and alertness ratings. Thus, this newly developed questionnaire contains three distinct dimensions. To reflect the new content, the scale is labelled morningness–eveningness-stability-scale improved (MESSi). 相似文献
Pure zirconium oxide (ZrO2) nanocrystals with diameters 10-30 nm are fabricated from bis-aqua, tris-acetylacetonato zirconium(IV) nitrate; [Zr(acac)3(H2O)2](NO3); by thermal decomposition. The different combinations of oleylamine, or polyethyleneglycol (PEG) and triphenylphosphine, were added as surfactants to control the particle size. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectroscopy, photoluminescence spectroscopy (PL), Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) to depict the phase and morphology. The synthesized ZrO2 nanoparticles have a cubic structure. The FT-IR spectrum showed the purity of obtained ZrO2 nanocrystals with cubic phase. The UV-Visible absorption peak for ZrO2 was observed at 233 nm (5.3 eV in photon energy). The band at 363 nm for cubic ZrO2 nanocrystals was found. 相似文献
The present study investigates the effect of gibberellic acid (GA3), a terpenoid and phytohormone, on the digestive physiology and intermediary metabolism of the cotton bollworm Helicoverpa armigera Hübner (Lepidoptera, Noctuidae). Incorporation of GA3 (800 μg g?1 diet) in an artificial diet results in significant reductions in the rates of diet consumption and the efficiency of conversion of food consumption by by H. armigera larvae. The relative growth rate decreases as the concentration increases. The relative α‐amylase activity in sixth‐instar larvae of H. armigera decreases significantly after ingestion of four concentrations of GA3. Histological studies of the midgut in GA3‐treated larvae (800 μg g?1 diet) show degeneration of the epithelial cells. The alanine and aspartate aminotransferase activity decreases at the highest concentration. However, acid phosphatase, alkaline phosphatase, γ‐glutamyl transferase and lactate dehydrogenase activity increase significantly compared with the control. The results clearly demonstrate the adverse effects of GA3 on H. armigera via interruption of nutritional physiology and metabolism. 相似文献
Effects of different shear rates (14, 25, and 50 s−1), gum concentrations (3%, 3.5%, and 4%), and temperatures (5–65 °C) on flow properties of Alyssum homolocarpum seed gum solutions were investigated using a rotational viscometer. The experimental data were fitted with three time-dependent
rheological models, namely second-order structural kinetic model, Weltman model, and first-order stress decay model with a
non-zero stress value. The rate constant and extent of viscosity strongly depended on the shear rate, gum concentration, and
temperature. It was found that A. homolocarpum seed gum samples exhibited shear thinning and thixotropic behavior for all concentrations and temperatures. The amount of
structural breakdown decreased with shear rate, but it did not have a general trend with concentration and temperature. The
extent of thixotropy increased with increasing gum concentration and decreased with increasing temperature and shear rate.
In this work, the decay rate constant generally increased with increasing shear rate; however, it did not have any trend with
concentration and temperature. 相似文献
Ghrelin has recently been shown to improve renal function in rat with acute renal failure. In this setting, the protective
effects have been suggested to be due to its antioxidant properties. Thus, the aim of this study was to measure the antioxidant
abilities of this hormone via enzymatic and lipid peroxidation analyses. Wistar rats were divided into two control and two
treatment groups, the treated animals receiving 3 nmol of ghrelin as subcutaneous administrations on each of 10 consecutive
days and physiological saline injected to controls. Catalase (CAT) activity was significantly higher in the treated animals
when compared to controls, while in contrast, lipid peroxidation measured by thiobarbituric acid reactive substances (TBARS),
was significantly reduced in the ghrelin treated animals. Furthermore, superoxide dismutase (SOD) activity and glutathione
(GSH) content were both much higher in treated female rats than in controls and although there was a slight increase in glutathione
peroxidase (GPx) activity in kidneys of ghrelin treated rats, the difference was insignificant. These findings suggest that
ghrelin has beneficial antioxidant properties in the rat kidney by increasing antioxidant enzyme activities. These effects
were more noticeable in treated female rats, possibly due to higher levels of estrogen. 相似文献
Copper oxide nanomaterials’ (NMs) are important for the critical roles of Cu as a micronutrient that its
improper concentration could cause toxicity or deficiency in plant. The Nano form of CuO could amplify the effects
due to special characteristic of nano materials.
Method
Treatments of 0.1, 0.5, and 2.5 μM and NM of copper with three replications were applied to plants under
hydroponic conditions. Physiological parameters and expression of IRT1 and CAT genes were investigated.
Results
Copper absorption decreased according to MMs-CuO ? NMs-CuO ?? CuSO4 pattern. The positive effects
of MMs-CuO on plant copper content were higher than those of nanomaterials and CuSO4. MMs-CuO effect was
more significant on plant biomass increase compared to the control. Rue plant needed lower amounts of copper for
better plant growth. The treatments increased protein and carotenoids content in leaves compared with control.
Changes in total chlorophyll content under three copper forms were very low and were only increased in leaves at
0.1 μM CuSO4. The NMs-CuO and MMs-CuO similarly reduced leaves’ Cu, MDA and ROS contents, and SOD
activities. CAT enzyme activity had a similar pattern in three copper forms. CAT enzyme activity was only induced
under the lowest level of three forms, while at other levels of Cu, it was reduced. NMs-CuO had a more negative
effect on IRT1 relative gene expression in root compared with other iron forms. The IRT1 relative gene expression
in shoots was positively affected under 2.5 μM CuSO4, 0.5 μM MMs-CuO, and 0.1 and 2.5 μM NMs CuO
treatments.
Conclusion
The effect of micro- and nano-CuO on physiology and gene expression mechanisms in rue plants is shown to be does-dependent.
Herein, the interaction of iron nanoparticle (Fe-NP) with cytochrome c (Cyt c) was investigated, and a range of techniques such as dynamic light scattering (DLS), zeta potential measurements, static and synchronous fluorescence spectroscopy, near and far circular dichroism (CD) spectroscopy, and ultraviolet–visible (UV–vis) spectroscopy were used to analyze the interaction between Cyt c and Fe-NP. DLS and zeta potential measurements showed that the values of hydrodynamic radius and charge distribution of Fe-NP are 83.95 ± 3.7 nm and 4.5 ± .8 mV, respectively. The fluorescence spectroscopy results demonstrated that the binding of Fe-NP with Cyt c is mediated by hydrogen bonds and van der Waals interactions. Also Fe-NP induced conformational changes in Cyt c and reduced the melting temperature value of Cyt c from 79.18 to 71.33°C. CD experiments of interaction between Fe-NP and Cyt c revealed that the secondary structure of Cyt c with the dominant α-helix structures remained unchanged whereas the tertiary structure and heme position of Cyt c are subjected to remarkable changes. Absorption spectroscopy at 695 nm revealed that Fe-NP considerably disrupt the Fe…S(Met80) bond. In addition, the UV–vis experiment showed the peroxidase-like activity of Cyt c upon interaction with Fe-NP. Hence, the data indicate the Fe-NP results in unfolding of Cyt c and subsequent peroxidase-like activity of denatured species. It was concluded that a comprehensive study of the interaction of Fe-NP with biological system is a crucial step for their potential application as intracellular delivery carriers and medicinal agents. 相似文献