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61.
This paper investigates whether a green kind of design helps firms increase their capabilities for inventing in the environmental domain and whether it does so more than ‘standard’ design. It also investigates whether the effect of ‘green-matching’ between new design and technologies is conditional on firms’ innovative capabilities, as reflected by their R&D expenditure. We address these research questions with respect to the world's top R&D investors, looking at their intellectual property rights at the United States Patent and Trademark Office (USPTO) and proposing an original textual identification of green designs and trademarks. We find that green design increases environmental inventions by top R&D investors, and to a greater extent than non-environmental ones. Standard design also stimulates environmental inventions, but to a lesser extent than green design. The ‘green-matching’ actually helps, but internal innovative capabilities are required to make it effective: a green-tech ‘prize’ emerges from green design, but only once a minimum threshold of R&D expenditure has been reached.  相似文献   
62.
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.  相似文献   
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Education and Information Technologies - Mobile apps represent a resource with great potential for encouraging the development of many skills, given the high number of apps available and the quick...  相似文献   
64.
Videos can be used as didactic tools for self‐learning under several circumstances, including those cases in which students are responsible for the development of this resource as an audiovisual notebook. We compared students' and teachers' perceptions regarding the main features that an audiovisual notebook should include. Four questionnaires with items about information, images, text and music, and filmmaking were used to investigate students' (n = 115) and teachers' perceptions (n = 28) regarding the development of a video focused on a histological technique. The results show that both students and teachers significantly prioritize informative components, images and filmmaking more than text and music. The scores were significantly higher for teachers than for students for all four components analyzed. The highest scores were given to items related to practical and medically oriented elements, and the lowest values were given to theoretical and complementary elements. For most items, there were no differences between genders. A strong positive correlation was found between the scores given to each item by teachers and students. These results show that both students' and teachers' perceptions tend to coincide for most items, and suggest that audiovisual notebooks developed by students would emphasize the same items as those perceived by teachers to be the most relevant. Further, these findings suggest that the use of video as an audiovisual learning notebook would not only preserve the curricular objectives but would also offer the advantages of self‐learning processes. Anat Sci Educ 7: 209–218. © 2013 American Association of Anatomists.  相似文献   
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This study addressed recruiting principals into low performing schools. A sample (N = 619) of principals, assistant principals, central office administrators, school counselors, and teacher-leaders from the 29th largest school district in the United States role-played as applicants for principal vacancies at schools classified as low-performing based on results of standardized student achievement tests. The study had an experimental design and involved use of a recruitment simulation. Rating jobs depicted on simulated principal recruitment announcements, principals and assistant principals rated the job highest while school counselors rated the jobs lowest. Among the teacher-leaders, teacher-administrative interns rated the job higher than did highly skilled educators or resource teachers. Implications for recruitment practice and future evaluation research are discussed.  相似文献   
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For centuries, there have been discussions as to whether only experts can judge the quality of cultural output, or whether the taste of the public also has merit. This paper tries to answer that question empirically, using national finals of the Eurovision Song Contest. We show that experts are better judges of quality in the sense that the outcome of finals judged by experts is less sensitive to factors unrelated to quality than the outcome of finals judged by public opinion. Yet, experts are not perfect; their judgment does still depend on such factors. This is also the case in the European finals of the contest.  相似文献   
70.

Introduction:

Two Italian adults arrived at the Emergency Department referring diarrhea, nausea and vomiting for 4 days; weakness, fatigue and visual hallucinations were also complained of. Patients reported the ingestion of some leaves of a plant, which they supposed to be “donkey ears”, a week before. Physical examination showed hypotension and bradycardia and ECG examination disclosed sinus rhythm and repolarization abnormalities (scooping of the ST-T complex) in both patients and a 2:1 AV block in the man.

Materials and methods:

Digoxin concentration was evaluated twice for each patient (at the admission and after 4 hours) by the automated immunoassay system ADVIA Centaur®. Digitoxin concentration was evaluated by liquid chromatography-mass spectrometry (LC-MS/MS).

Results:

Despite clinical picture was suggestive of digitalis intoxication, digoxin levels were undetectable. Due to the more severe clinical picture, the male patient was treated with anti-digoxin antibodies (Digifab®) achieving a good clinical improvement and remission of the AV block within two hours. Initial diagnosis was confirmed by LC-MS/MS showing high digitoxin concentrations, but digoxin was undetectable. Patients remained stable and 48 hours later were discharged from the hospital.

Conclusion:

Whereas digoxin determination frequently relies on monoclonal antibodies which do not cross-react to digitoxin, polyclonal antibodies constituting Digifab® recognize a large spectrum of cardiac glycosides, including digitoxin. This report emphasizes the primary role of the clinical approach to patients in the emergency setting and how an active communication and a continuous sharing of professional experiences between Laboratory and Clinicians ensure an early and correct diagnosis.  相似文献   
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