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181.
Vandermoere F Blanchemanche S Bieberstein A Marette S Roosen J 《Public understanding of science (Bristol, England)》2011,20(2):195-206
In spite of great expectations about the potential of nanotechnology, this study shows that people are rather ambiguous and pessimistic about nanotechnology applications in the food domain. Our findings are drawn from a survey of public perceptions about nanotechnology food and nanotechnology food packaging (N = 752). Multinomial logistic regression analyses further reveal that knowledge about food risks and nanotechnology significantly influences people's views about nanotechnology food packaging. However, knowledge variables were unrelated to support for nanofood, suggesting that an increase in people's knowledge might not be sufficient to bridge the gap between the excitement some business leaders in the food sector have and the restraint of the public. Additionally, opposition to nanofood was not related to the use of heuristics but to trust in governmental agencies. Furthermore, the results indicate that public perceptions of nanoscience in the food domain significantly relate to views on science, technology, and nature. 相似文献
182.
Gupta S Verma M Gupta AK Kaur A Kaur V Singh K 《Indian journal of clinical biochemistry : IJCB》2011,26(2):178-181
Thyroid function tests are very important for the diagnosis and monitoring of patients with thyroid dysfunction. The guidelines
recommend serum thyroid stimulating hormone (TSH) as the single most reliable test to diagnose all common forms of hypothyroidism
and hyperthyroidism. The aim of this study was to analyze the ordering pattern for thyroid function tests by physicians and
the analysis of results based on the clinical history. The mean age of the patients was 32.5 ± 6.5 years. Majority of samples
(87.7% of total) were received from the departments of Medicine and Gynae. Thyroid profiles (47.5%) were ordered more frequently
as compared to TSH only (46%). There was no significant difference in the percentage of normal reports for both types of tests.
77.8% of TFT and 76.6% of TSH samples had results within the reference range. The percentage of abnormal results was 13.7%
in the patients who were screened for thyroid disorders. There is a need to redefine the case definition for thyroid dysfunction
and order the appropriate test in a rational and cost effective manner. 相似文献
183.
Booth A 《Health information and libraries journal》2011,28(4):331-334
This feature briefly examines the development of knowledge translation, knowledge transfer and the knowledge broker role as constituting the next manifestation of the movement that brought us evidence based medicine and its derivatives. It examines the extent to which health information professionals currently meet the specification for a knowledge broker role. In doing so it assesses the strengths and weaknesses of the profession when ranged alongside the five components of the knowledge transfer process that is, problem identification; knowledge development and selection; analysis of context; knowledge transfer interventions; and knowledge utilization. Current deficiencies also lie in a need for political astuteness and awareness and in a lack of knowledge of the most significant models of behavioural change. The feature concludes by examining the potential for knowledge team approaches arguing that gains from a wider perspective that encompasses the entire knowledge process may be even more significant than the pooling of collective knowledge, skills and expertise. 相似文献
184.
185.
Dimov N Muñoz L Carot-Sans G Verhoeven ML Bula WP Kocer G Guerrero A Gardeniers HJ 《Biomicrofluidics》2011,5(3):34102-3410212
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS). 相似文献
186.
Revzin A 《Biomicrofluidics》2011,5(3):31901-319013
This Preface describes exciting papers contributed to the Special Topic section on manipulation and analysis of cells using microsystems. Brief summaries of each paper are provided and general trends are discussed. 相似文献
187.
In this paper, we present a movement-based assay to observe adaptability in Caenorhabditis elegans locomotion behavior. The assay comprises a series of sinusoidal microchannels with a fixed wavelength and modulating (increasing or decreasing) amplitude. The channel width is comparable to the body diameter of the organism. Worms are allowed to enter the channel from the input port and migrate toward the output port. Within channel sections that closely match the worm's natural undulations, the worm movement is relatively quick and steady. As the channel amplitude increases or decreases along the device, the worm faces difficulty in generating the propulsive thrust, begins to slow down and eventually fails to move forward. A set of locomotion parameters (i.e., average forward velocity, number and duration of stops, range of contact angle, and cut-off region) is defined for worm locomotion in modulated sinusoidal channels and extracted from the recorded videos. The device is tested on wild-type C. elegans (N2) and two mutants (lev-8 and unc-38). We anticipate this passive, movement-based assay can be used to screen nematodes showing difference in locomotion phenotype. 相似文献
188.
In this special issue of Biomicrofluidics, a wide variety of applications of microfluidics to tissue engineering and cell biology are presented. The articles illustrate the benefits of using microfluidics for controlling the cellular environment in a precise yet high rate manner using minimum reagents. The topic is very timely and takes a stab at portraying a glimpse of what is to come in this exciting and emerging field of research. 相似文献
189.
In this work a disposable, parallel microbioreactor (MBR) suitable for screening in batch or continuous mode is presented. The reactor consists of five parallel microchambers made of poly(dimethylsiloxane) bonded to a glass substrate. A grid structure is engraved on each chamber, allowing subsequent morphology imaging. Measurements are recorded over the entire cultivation period with constant parameters, namely, position and focus in the z-axis. The microdevice may be used for either parallel, uni- or multiparametric screening, and overcomes the drawback of gridless microwell plates which require expensive equipment such as an inverted microscope with an automatic stage. To validate the scalability from laboratory scale to microscale, and thus the cultivation protocol in the MBR, the germination of fungal spores (A. ochraceus) is evaluated for two different key magnitudes (pH and temperature) and compared to the results obtained from conventional laboratory scale systems (flasks and agar plates). Information on germination capacity with regard to interspecies' variability allows for optimization of industrial processes as optimal pH and temperature matched to the mesoscopic cultivation systems. The germination conditions therefore remain unaffected inside the MBR, while providing the following advantages: (i) dramatic reduction of medium consumption, (ii) submerged cultivation with constant oxygen supply, (iii) assured low cost and disposability, and (iv) possibility of a continuous cultivation mode. 相似文献
190.
This study reports on the use of a microsystem for evaluation of photodynamic therapy (PDT) procedures on the "mixed" (carcinoma-normal) cultures. Balb/3T3 (normal mouse embryo) and A549 (human lung carcinoma) cells were tested in separated and "mixed" cultures. Interactions and migration of cells cultured together were observed. The PDT procedures were examined in the hybrid (PDMS/glass) microsystem which contains cell culture microchambers integrated with network of microchannels. We investigated that the number of dead cells after PDT procedures is dependent on the kind of cell culture. Moreover, the influence of the carcinoma cells on the viability of normal cells in the "mixed" culture was observed. 相似文献