Bandpass sorting of heterogeneous cells using a single surface acoustic wave transducer pair     

Gergely Simon  Caroline Busch  Marco A. B. Andrade  Julien Reboud  Jonathan M. Cooper  Marc P. Y. Desmulliez  Mathis O. Riehle  Anne L. Bernassau 《Biomicrofluidics》2021,15(1)

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   

Editorial     

Marco Todeschini 《欧洲师范教育杂志》1995,18(2-3):139-142

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Recruiting Principals to Lead Low-performing Schools: Effects on Job Attractiveness     

Geneva A. Stark-Price  Marco A. Mu?oz  Paul A. Winter  Joseph M. Petrosko 《Journal of Personnel Evaluation in Education》2006,19(1-2):69-83

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   

Improving Teaching and Learning Through Evaluation: A Special Issue on the National Evaluation Institute     

Marco A. Mu?oz  Douglas R. Davis  Consortium for Research on Educational Accountability  Teacher Evaluation 《Journal of Personnel Evaluation in Education》2007,20(3-4):111-116

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Editorial     

Marco Todeschini 《欧洲师范教育杂志》1994,17(3):139-142

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Expert Judgment Versus Public Opinion – Evidence from the Eurovision Song Contest     

Marco?A.?HaanEmail author  S.?Gerhard?Dijkstra  Peter?T.?Dijkstra 《Journal of Cultural Economics》2005,29(1):59-78

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   

Accidental digitoxin intoxication: an interplay between laboratory and clinical medicine     

Luigi M Castello  Sophie Negro  Francesca Santi  Isabella Zanotti  Matteo Vidali  Marco Bagnati  Giorgio Bellomo  Gian Carlo Avanzi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(3):380-384

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   

Creatine kinase activity weakly correlates to volume completed following upper body resistance exercise     

Machado M  Willardson JM  Silva DR  Frigulha IC  Koch AJ  Souza SC 《Research quarterly for exercise and sport》2012,83(2):276-281

In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets.  相似文献   

Design issues for human-machine platform interface in cable-based parallel manipulators for physiotherapy applications     

Marco CECCARELLI  Lotfi ROMDHANE 《浙江大学学报(A卷英文版)》2010,11(4):231-239

We outline problems and potential solutions for feasible human-machine interfaces using cable-based parallel manipulators for physiotherapy applications. From an engineering perspective, we discuss the design constraints related to acceptance by patients and physiotherapist users. To date, most designs have focused on mobile platforms that are designed to be operated as an end-effector connected to human limbs for direct patient interaction. Some specific examples are illustrated from the authors＇ experience with prototypes available at Laboratory of Robotics and Mechatronics （LARM）, Italy.  相似文献   

From splendid isolation to crossed boundaries? The futures of teacher education in the light of activity theory     

Marco Snoek 《Teacher Development》2013,17(3):307-321

Many policy documents addressing the future of teacher education do not take into account the fundamental unpredictability of the future, nor the opposing forces that will try to influence that future. Through the analysis of 48 scenario documents on the future of education or teacher education, we identified a set of unpredictable key factors that have to be taken into account when addressing the future of teacher education. We also identified four main futures that may lie ahead for teacher education. We analyzed these four scenarios using the concepts of activity systems, boundary objects, and boundary crossing. This revealed that the extent to which activity systems are open to boundary crossing and are willing to remove institutional boundaries will largely define the future that lies ahead for teacher education. Future scenarios in themselves can play a role as boundary objects that facilitate the dialogue and boundary crossing between these activity systems.  相似文献