Microfluidic production of single micrometer-sized hydrogel beads utilizing droplet dissolution in a polar solvent     

Sari Sugaya  Masumi Yamada  Ayaka Hori  Minoru Seki 《Biomicrofluidics》2013,7(5)

In this study, a microfluidic process is proposed for preparing monodisperse micrometer-sized hydrogel beads. This process utilizes non-equilibrium aqueous droplets formed in a polar organic solvent. The water-in-oil droplets of the hydrogel precursor rapidly shrunk owing to the dissolution of water molecules into the continuous phase. The shrunken and condensed droplets were then gelled, resulting in the formation of hydrogel microbeads with sizes significantly smaller than the initial droplet size. This study employed methyl acetate as the polar organic solvent, which can dissolve water at 8%. Two types of monodisperse hydrogel beads—Ca-alginate and chitosan—with sizes of 6–10 μm (coefficient of variation < 6%) were successfully produced. In addition, we obtained hydrogel beads with non-spherical morphologies by controlling the degree of droplet shrinkage at the time of gelation and by adjusting the concentration of the gelation agent. Furthermore, the encapsulation and concentration of DNA molecules within the hydrogel beads were demonstrated. The process presented in this study has great potential to produce small and highly concentrated hydrogel beads that are difficult to obtain by using conventional microfluidic processes.  相似文献   

The Effect of Augmented Reality based applications on achievement and attitude towards science course in distance education process     

&#;etin  Hakan  T&#;rkan  Azmi 《Education and Information Technologies》2022,27(2):1397-1415

Education and Information Technologies - This study aims to enrich a theme in the science course in the distance education process with augmented reality-based applications and to examine the...  相似文献   

Blending video games with learning: Issues and challenges with classroom implementations in the Turkish context     

Hakan Tüzün 《British journal of educational technology : journal of the Council for Educational Technology》2007,38(3):465-477

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Can a collaborative network environment enhance essay-writing processes?   总被引：1，自引：0，他引：1  

Sari Lindblom-Ylänne  Heikki Pihlajamäki 《British journal of educational technology : journal of the Council for Educational Technology》2003,34(1):17-30

The aim of this study is to examine whether a computer-supported learning environment enhances essay writing by providing an opportunity to share drafts with fellow students and receive feedback from a draft version. Data for this study were provided by 25 law students who were enrolled in a course in legal history at the University of Helsinki in February 2001. Both the students and the teacher were interviewed. The interviews showed that the students' experiences of the essay-writing process were very positive. The teacher's experiences were in line with the students'. The results showed that the students seemed to divide into two groups concerning their experiences towards sharing written drafts with peers: those who were very enthusiastic and enjoyed the possibility to share drafts and those who, on the other hand, felt that the idea of sharing unfinished essays was too threatening for them and required too much openness. The results further showed that the active use of a computer-supported learning environment was related to good essay grades.  相似文献   

Evaluation of the Steelex M600H coagulometer prothrombin time-international normalized ratio assay with Steelex test reagents     

Budak YU  Huysal K  Polat M  Tarakçi G  Uçar H 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(1):121-126

Introduction

The aim of the present study was to validate prothrombin time (PT) international normalized ratio (INR) results obtained using Steelex test reagents and a Steelex coagulometer (Steelex Scientific Instrument Company, Beijing, China), in comparison with use of a well-established standard test employing Pacific Hemostasis reagents (Fisher Diagnostics, Middletown, VA, USA) and Teco Coatron A4 coagulometer (Teco Medical Instruments GmbH, Neufahrn, Germany).

Materials and methods:

Between- and within-day coefficients of variation (CVs) of both assays were calculated using control samples provided by the test manufacturers. Samples from 90 subjects were collected and INR values were determined in a double-blind parallel manner employing both systems.

Results:

The within-day coefficients of variation (CVs) in INR estimates ranged from 2.6% (INR = 1.12) to 3.1% (INR = 2.51) for the Steelex system and from 2.1% (INR = 1.09) to 1.8% (INR = 2.8) for the Pacific test; the between-day values ran from 3.4% (INR = 1.16) to 7.9% (INR = 2.64) and from 3.3% (INR = 1.1) to 2.3% (INR = 2.7), respectively. Passing-Bablok fit of the of the Steelex and Pacific methods yielded the equation: Steelex INR = 0.85 (0.79–0.91) × Pacific INR + 0.12 (−0.02–0.21), whereas the CUSUM linearity P value was < 0.01. The mean bias as determined by the Bland-Altman test was −0.156 (−0.912–0.600).

Conclusion:

The results obtained using Steelex reagents and the M600H coagulometer are not equivalent to those obtained using Pacific Hemostasis reagents and a Teco Coatron A4 coagulometer, at least in the therapeutic range.  相似文献   

Comment on: Study of Oxidative Stress in Vitiligo     

Turgay Ulas  Mehmet Sinan Dal  Mehmet Emin Demir  Hakan Buyukhatipoglu 《Indian journal of clinical biochemistry : IJCB》2012,27(3):318-318

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The impact of instructional technology in Turkey   总被引：1，自引：0，他引：1  

Cengiz Hakan Aydin  Marina Stock McIsaac 《Educational technology research and development : ETR & D》2004,52(1):105-112

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Graduates’ evaluations of usefulness of university education,and early career success – a longitudinal study of the transition to working life     

Tarja Tuononen  Anna Parpala  Sari Lindblom-Ylänne 《Assessment & Evaluation in Higher Education》2019,44(4):581-595

A successful transition from university to working life requires that graduates are able to employ their education and academic competences in real working-life contexts. Our previous research showed that graduates varied in how they were able to reflect on their competences at the time of graduation. The present longitudinal mixed-method study follows the same graduates and explores their evaluations of the usefulness of university education and career success, three years after graduation. The follow-up data consisted of 57 graduates’ survey answers analysed by quantitative and qualitative methods. The results showed that graduates who were able to describe and evaluate more competences at the time of graduation perceived their current jobs to correspond more to their education. Graduates with more limited evaluations of their competences, on the other hand, had experienced more challenges related to employment and were more uncertain of their goals. The results also showed that having diverse competences and an ability to recognise them at the time of graduation is important for later career success and may also be related to what kind of challenges graduates face in working life.  相似文献   

How do the different study profiles of first-year students predict their study success,study progress and the completion of degrees?     

Anne Haarala-Muhonen  Mirja Ruohoniemi  Anna Parpala  Erkki Komulainen  Sari Lindblom-Ylänne 《Higher Education》2017,74(6):949-962

The relationship between study success and the nature of 550 first-year law students’ study processes was investigated using a modified version of the Approaches to Learning and Studying Inventory. The students were classified into four study profiles according to their approaches to learning, indicating the nature of their study processes. In addition, the students were divided into six study success groups on the basis of their earned study credits and grade point average. The results showed that both approaches to learning and study success in the first study year predicted graduation time and the completion of the degree. Thus, it is important that faculties actively use measures, such as the inventory used in the present study, to promote first-year students’ awareness of their study practices and support the progress of their studies. Individual students need tailored guidance in transitioning to university studies and identifying the demands of the study programme.  相似文献   

Total thyroidectomy is safer with identification of recurrent laryngeal nerve     

Canbaz H  Dirlik M  Colak T  Ocal K  Akca T  Bilgin O  Tasdelen B  Aydin S 《Journal of Zhejiang University. Science. B》2008,9(6):482-488

Objective: To investigate the effect of recurrent laryngeal nerve (RLN) identification on the complications after total thyroidectomy and lobectomy. Methods: Total 134 consecutive patients undergoing total thyroidectomy or thyroid lobectomy from January 2003 to November 2004 were investigated retrospectively. Patients were divided into two groups: RLN identified (Group A) or not (Group B). The two groups were compared for RLN injury and hypocalcaemia. Results: The numbers of patients and nerves at risk were 71 and 129 in Group A, and 63 and 121 in Group B, respectively. RLN injury in Group A (0) was significantly lower than that in Group B (5[7.9%]) patients, 7 [5.8%] nerves) for the numbers of patients (P=-0.016) and nerves at risk (P=0.006). Temporary hypocalcaemia was significantly higher in Group A than in Group B (14 [24.1%] vs 6 [10.3%], P=0.049).Permanent complications in Group B were significantly higher than those in Group A (13 [20.6%] vs 4 [5.6%], P=0.009). Conclusion: RLN injury was prevented and permanent complications were decreased by identifying the whole course and branches of the recurrent laryngeal nerve during total thyroidectomy.  相似文献