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91.
92.
The development of children's verbal communication about feeling states was studied by analyzing naturally occurring conversations at home. The data were recorded during two longitudinal studies. In Study 1, 43 second-born children were observed with mother and older sibling at 18 and 24 months. In Study 2, 16 firstborn children were observed with mother and younger sibling at 25 and 32 months. Both studies showed that by 2 years of age, the majority of children referred to a range of feeling states in self and other, and they discussed the cause of feeling states in a variety of contexts (including pretend games). References to feeling states made by mother and older sibling when the target child was 18 months were positively correlated with the target child's speech about feeling states at 24 months. Both mothers and older siblings mentioned feeling states more frequently to girls than to boys. By 24 months, the girls themselves referred to feeling states significantly more often than boys. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Experimental and theoretical approaches were used to understand the degradation behavior of networks formed from the chain polymerization of multi-functional macromers. A typical experimental mass loss profile and theoretical model are presented and discussed to illustrate the various regions of erosion. Specifically, the degree of connectivity of the network was shown to influence the percent mass loss at reverse gelation, and the percent cyclization was shown to influence the overall shape of the mass loss profile. Finally, the theoretical predictions of mass loss were compared to experimental data for macromers with variations in their molecular weight and degree of functionality (i.e. variations in the initial network crosslinking density). Changes in the volumetric swelling ratio and compressive modulus were measured with time to obtain the degradation kinetic constant for each macromer system, ranging from 1.5×10−4 min−1 to 3.0×10−5 min−1. Results demonstrate that the theoretical predictions capture the mass loss profiles of all three systems, and as the crosslinking density of the initial network was decreased the overall time for complete degradation of the gels was also decreased. 相似文献
94.
The effect of walnut intake on factors related to prostate and vascular health in older men 总被引:2,自引:0,他引:2
Kim J Spaccarotella Penny M Kris-Etherton William L Stone Deborah M Bagshaw Valerie K Fishell Sheila G West Frank R Lawrence Terryl J Hartman 《Nutrition journal》2008,7(1):1-10
Background
Tocopherols may protect against prostate cancer and cardiovascular disease (CVD).Methods
We assessed the effect of walnuts, which are rich in tocopherols, on markers of prostate and vascular health in men at risk for prostate cancer. We conducted an 8-week walnut supplement study to examine effects of walnuts on serum tocopherols and prostate specific antigen (PSA). Subjects (n = 21) consumed (in random order) their usual diet +/- a walnut supplement (75 g/d) that was isocalorically incorporated in their habitual diets. Prior to the supplement study, 5 fasted subjects participated in an acute timecourse experiment and had blood taken at baseline and 1, 2, 4, and 8 h after consuming walnuts (75 g).Results
During the timecourse experiment, triglycerides peaked at 4 h, and gamma-tocopherol (γ-T) increased from 4 to 8 h. Triglyceride – normalized γ-T was two-fold higher (P = 0.01) after 8 versus 4 h. In the supplement study, change from baseline was +0.83 ± 0.52 μmol/L for γ-T, -2.65 ± 1.30 μmol/L for alpha-tocopherol (α-T) and -3.49 ± 1.99 for the tocopherol ratio (α-T: γ-T). A linear mixed model showed that, although PSA did not change, the ratio of free PSA:total PSA increased and approached significance (P = 0.07). The α-T: γ-T ratio decreased significantly (P = 0.01), partly reflecting an increase in serum γ-T, which approached significance (P = 0.08).Conclusion
The significant decrease in the α-T: γ-T ratio with an increase in serum γ-T and a trend towards an increase in the ratio of free PSA:total PSA following the 8-week supplement study suggest that walnuts may improve biomarkers of prostate and vascular status. 相似文献95.
Ward KR Barbee RW Reynolds PS Filho IP Tiba MH Torres L Pittman RN Terner J 《Analytical chemistry》2007,79(4):1514-1518
Resonance Raman spectroscopy offers a mechanism for the noninvasive measurement of in vivo and in situ hemoglobin oxygen saturation (HbO(2)Sat) in living tissue. Clinically informative signals can be provided by resonance enhancement with deep violet excitation. It is notable that fluorescence does not significantly degrade the quality of the signals. During the controlled hemorrhage and resuscitation of rats, signal intensity ratios of oxy- vs. deoxyhemoglobin from sublingual mucosa correlated with co-oximetry values of blood withdrawn from a central venous catheter. The spectroscopic application described here has potential as a noninvasive method for the diagnosis of clinical shock and guidance of its therapy. 相似文献
96.
In order to solve the water issues when 13X zeolite was applied to capture CO 2 from wet flue gas by vacuum swing adsorption process, multi-layered adsorption system was considered regarding activated alumina F200 and silica gel based Sorbead WS as pre-layer materials. LBET (extended Largmuir-BET) model and extended CMMS (cooperative multimolecular sorption) equation were simulated respectively to describe water loading on F200 and Sorbead WS. The two equations can be well added into our in-house simulator to simulate double-layered CO 2 -VSA (vacuum swing adsorption) process. Results indicated that water can be successfully stopped in pre-layers with a good CO 2 capture performance. 相似文献
97.
Consumption of Bifidobacterium animalis subsp. lactis BB‐12 impacts upper respiratory tract infection and the function of NK and T cells in healthy adults 下载免费PDF全文
98.
Precise identification of end-diastole (ED), corresponding to the end of diastole and start of systole, is crucial for accurate assessment of cardiac function. The aims of this study were to develop a new algorithm based on peak curvature (kappa(p)) for detecting ED as a "corner" in left ventricular pressure (LVP) signals, and to compare this approach with "gold-standard" ED obtained by manual annotation (ED(man)) and ED calculated with previously described algorithms that use an LVP first-derivative threshold (dP/dt(0) or dP/dt(100)), the peak LVP second-derivative (d(2)P/dt(2)(p)) or ECG R-wave peak (ECG(R)). Using customized software, all algorithms were applied to data derived from 213 large animal studies spanning a wide range of animal ages (fetus to adult), heart rates, inotropic states, and loading conditions. Differences between ED(man) and each algorithm were then compared after defining an acceptance region for the ED detection based on ED(man) interobserver variability. ED detected with kappa(p) was the most accurate (p < 0.001) and least variable (p < 0.001), with 97% of measurements within the acceptance region and difference from ED(man) of (1.5 +/- 4.2) ms. By contrast, ED was often detected early with dP/dt(0) and dP/dt(100) , and late with d(2)P/dt(2)(p) and ECG(R). These results indicate that the peak curvature algorithm using LVP provides accurate and reliable detection of ED. 相似文献
99.
Schäfer A van der Zwaag W Francis ST Head KE Gowland PA Bowtell RW 《Magma (New York, N.Y.)》2008,21(1-2):113-120
Object The sensitivity of spin echo (SE) experiments to blood oxygenation level dependent (BOLD) contrast was explored in a study
of the same six subjects carried out at 3 and 7 T.
Materials and methods Multi-slice, single shot, spin echo, echo planar images with a voxel size of 1 × 1 × 3 mm3 were acquired at three different echo times, during execution of a simple motor task.
Results Significant activation was observed at all echo times at both field strengths. Analysis of the fractional signal change as
a function of echo time indicated that the change in relaxation rate, ΔR
2, at 7 T was −0.51 ± 0.14 s
−1, which was 1.3 times larger than the value found at 3 T. Measurements of the percentage signal change on activation and temporal
signal to noise ratio showed that there was an increase in the BOLD contrast to noise ratio (CNR) at 7 versus 3 T by a factor
of 1.9. There was no overlap of areas of significant activation in the SE data acquired at either field strength with the
site of large veins.
Conclusion SE-BOLD CNR in motor cortex was found to increase significantly at 7 T compared with 3 T. 相似文献
100.
Leonardo da Vinci was a strong advocate for using sketches to stimulate the human imagination. Sketching is often considered
to be integral to the process of design, providing an open workspace for ideas. For these same reasons, children use sketching
as a simple way to express visual ideas. By merging the abstraction of human drawings and the freedom of virtual reality with
the tangibility of physical tokens, Tangled Reality creates a rich mixed reality workspace. Tangled Reality allows users to build virtual environments based on simple colored sketches and traverse them using physical vehicles overlayed
with virtual imagery. This setup allows the user to “build” and “experience” mixed reality simulations without ever touching
a standard computer interface. 相似文献