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61.
This study assess the usefulness of the tympanogram as a screening tool for identifying otitis media and serous otitis media in preterm infants. Twenty-six infants from the NICU were assessed on the same day by two examiners using tympanometry and pneumatic otoscopy. The results were recorded separately and compared after all infants were tested. An audiologist independently interpreted each of the tympanogram strips. There was very little agreement between tympanometry and otoscopy results. The tympanogram was not found to be a repeatable or a reliable screening tool for assessing otitis media and serous otitis media in the NICU population. It was concluded that the NICU nurse must be aware of the signs and symptoms of otitis media and serous otitis media. If this diagnosis is raised for an infant in the NICU, careful visualization of the tympanic membrane should be carried out along with referrals to ear, nose, and throat and audiology experts.  相似文献   
62.
Glycan microarrays are useful tools for lectin glycan profiling. The use of a glycan microarray based on evanescent‐field fluorescence detection was herein further extended to the screening of lectin inhibitors in competitive experiments. The efficacy of this approach was tested with 2/3′‐mono‐ and 2,3′‐diaromatic type II lactosamine derivatives and galectins as targets and was validated by comparison with fluorescence anisotropy proposed as an orthogonal protein interaction measurement technique. We showed that subtle differences in the architecture of the inhibitor could be sensed that pointed out the preference of galectin‐3 for 2′‐arylamido derivatives over ureas, thioureas, and amines and that of galectin‐7 for derivatives bearing an α substituent at the anomeric position of glucosamine. We eventually identified a diaromatic oxazoline as a highly specific inhibitor of galectin‐3 versus galectin‐1 and galectin‐7.  相似文献   
63.
A new method for studying non-linear kinetics in an open reactor is described, including experimental, mathematical and numerical treatments. It is based on using a radioactive tracer for one of the reactants with the same kinetic properties. The tracer reactant is then included in the input flow in such a way that the sum of reactant and tracer reactant remains constant throughout the experiment. Thus no perturbation occurs when the tracer is added.It is shown that the non-linear initial system is reduced to a linear one for the tracer. The parameters of this tracer system are easily identified from experimental data, and then the parameters of the non-linear kinetics can be deduced.  相似文献   
64.
Recently, energy-efficient (EE) communications have received increasing interest specially in cellular networks. Promising techniques, such as multiple input multiple output (MIMO) and base station (BS) cooperation schemes, have been widely studied in the past to improve the spectral efficiency and the reliability. Nowadays, the purpose is to investigate how these techniques can reduce the energy consumption of the systems. In this paper, we address for a single-user scenario, the energy efficiency of two BSs cooperation under limited backhaul capacity. In order to evaluate the EE metric, we provide first an information-theoretical analysis based on the outage probability, for a quantization model over the backhaul. Then, we extend this EE analysis to a more practical approach with data transmission over the backhaul. For both approaches, we identify by numerical/simulation results the cooperation scenarios that can save energy depending on the backhaul capacity.  相似文献   
65.
Hollow latex particles are used as white pigments for paints and paper coatings. In the coating dispersion, each hollow particle is filled with water. As the coating dries, water vacates the latex, leaving an air-filled void sized to scatter light (~0.5 μm) within each particle. Examinations of dried coatings reveal that hollow particles can collapse, decreasing their light scattering efficiency. Cryogenic scanning electron microscopy (cryoSEM) was used to characterize the microstructure of coatings containing hollow latex during drying. Images suggest latex voids empty after air invades into the coating interstitial space and collapse occurs late in the drying process. The effects of temperature (10–60°C), humidity (20–80%), and binder concentration (0–30 wt%) on particle collapse were also studied through SEM of dried coating surfaces. High drying temperature, high humidity, and low binder concentrations promoted collapse. For hollow latex particles with porous shell walls, temperature and humidity had little effect, whereas binder increased collapse. From these results, a theoretical model is proposed. During drying, diffusion of water from the particle creates a vacuum inside the latex. The vacuum is either relieved by nucleation of a gas bubble from the dissolved air in the water-filled particle or it causes the particle to collapse by buckling.  相似文献   
66.
A self-determination theory perspective on parenting.   总被引:1,自引:0,他引:1  
This article describes research on parenting that supports children's need for autonomy. First, the authors define parental autonomy support and distinguish it from permissiveness or independence promotion. The authors also define psychologically controlling parenting and distinguish it from behavioral control (structure). Second, the authors present studies examining how parental autonomy support promotes healthy development. Indeed, clear and consistent positive effects arise from different types of studies, conducted with children of various ages. Parent observation studies suggest that parental autonomy support is associated with infants' motivation and toddlers' internalization. Parent interview studies reveal that an autonomy-supportive parental attitude relates to children's adjustment at school. Children self-report studies demonstrate a clear link between perceptions of parental autonomy support and psychosocial functioning amongst adolescents. Third, the correlates and precursors of parental psychological control and autonomy support are presented, with a special focus on parents' trust in their children's ability to develop in an autonomous manner. Finally, ideas for future research are suggested. Although self-determination theory is not strictly a developmental theory, it seems highly pertinent to the socialization of children, their internalization and development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
68.
A colorimetric method for quantitative measurement of free amino groups of water soluble chitin derivatives is described. The method utilizes genipin as a natural and specific reagent for determining the concentration of free amino groups in samples of water soluble chitin derivatives. The blue color adduct (complex) formed during genipin reaction with free amino groups was measured at about 589 nm and Beer-Lambert’s law obeyed over the concentration range of 50 to 300 mg/L. Parameters of analytical conditions were considered and kept constant during the experimental procedure. Highly acetylated water soluble chitin derivatives can be differentiated from water soluble chitosan using this genipin method. The colorimetric method with genipin was proved to be a rapid and efficient technique to determine the free amino groups in water soluble chitin derivatives. This method can also be applied for the detection of the enzymatic activity of chitindeacetylase.  相似文献   
69.
Micro-Rutherford backscattering spectrometry experiments were performed on a set of sintered titanium nitride samples implanted with xenon to a depth of about 150 nm. Implanted samples were annealed at 1500 °C during 5 h. Xe depth profile and its lateral distribution on the surface were measured. Surface morphology was observed using scanning electron microscopy. The results reveal that the microstructure plays an important role on xenon release. Moreover, the crystalline orientation of each grain could be a key parameter to explain the heterogeneous evolution of the surface during thermal treatments as well as Xe release from surface.  相似文献   
70.
Abstract

The modest appearance of I Like to Eat Right on the Dirt: A Child's Journey Back in Space and Time (1989), by Danny Lyon belies its true portent.1 As an experimental photo story, developed from purely photographic models, this book opens up whole new horizons.  相似文献   
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