Phaseguide-assisted blood separation microfluidic device for point-of-care applications     

Linfeng Xu  Hun Lee  Mariana Vanderlei Brasil Pinheiro  Phil Schneider  Deekshitha Jetta  Kwang W. Oh 《Biomicrofluidics》2015,9(1)

We propose a blood separation microfluidic device suitable for point-of-care (POC) applications. By utilizing the high gas permeability of polydimethylsiloxane (PDMS) and phaseguide structures, a simple blood separation device is presented. The device consists of two main parts. A separation chamber with the phaseguide structures, where a sample inlet, a tape-sealed outlet, and a dead-end ring channel are connected, and pneumatic chambers, in which manually operating syringes are plugged. The separation chamber and pneumatic chambers are isolated by a thin PDMS wall. By manually pulling out the plunger of the syringe, a negative pressure is instantaneously generated inside the pneumatic chamber. Due to the gas diffusion from the separation chamber to the neighboring pneumatic chamber through the thin permeable PDMS wall, low pressure can be generated, and then the whole blood at the sample inlets starts to be drawn into the separation chamber and separated through the phaseguide structures. Reversely, after removing the tape at the outlet and manually pushing in the plunger of the syringe, a positive pressure will be created which will cause the air to diffuse back into the ring channel, and therefore allow the separated plasma to be recovered at the outlet on demand. In this paper, we focused on the study of the plasma separation and associated design parameters, such as the PDMS wall thickness, the air permeable overlap area between the separation and pneumatic chambers, and the geometry of the phaseguides. The device required only 2 μl of whole blood but yielding approximately 0.38 μl of separated plasma within 12 min. Without any of the requirements of sophisticated equipment or dilution techniques, we can not only separate the plasma from the whole blood for on-chip analysis but also can push out only the separated plasma to the outlet for off-chip analysis.  相似文献   

Experience of integrating web 2.0 technologies     

Katerina Zdravkova  Mirjana Ivanovi?  Zoran Putnik 《Educational technology research and development : ETR & D》2012,60(2):361-381

Web users in the 21st century are no longer only passive consumers. On a contrary, they are active contributors willing to obtain, share and evolve information. In this paper we report our experience regarding the implementation of Web 2.0 concept in several Computer Ethics related courses jointly conducted at two Universities. These courses have been delivered to undergraduate and graduate students. The paper addresses main deficiencies of traditional E-learning noticed in earlier years and offers an alternative approach based on social media and collaborative creation of joint contents. Each Web 2.0 feature directly implemented in our courses is presented in details. Particular attention is paid to workload, student feedback and to observed benefits and disadvantages.  相似文献   

The Role of Action Research in Fostering Culturally-Responsive Practices in a Preschool Classroom     

Mariana Souto-Manning  Christina Hanson Mitchell 《Early Childhood Education Journal》2010,37(4):269-277

Early childhood teachers and educational programs are expected to be the primary resources as children experience different and sometimes conflicting cultural contexts. Early educators can play a paramount role as young children move through fluid identities and start recognizing and navigating within and across spaces of cultural differences—e.g., between home cultures and the socially-dominant school culture. In this sense, we draw attention to a multi-year action research study, paying particular attention to the process whereby an early childhood teacher investigated, problematized, and challenged the nature of curriculum and practices in a diverse preschool classroom. We focus on the role of action research in fostering culturally-relevant teaching. As we do so, we analyze an early childhood teacher’s shifting perceptions of what it means to engage in culturally-relevant teaching, respecting and honoring cultural diversities.  相似文献   

Svetovid—Interactive development and submission system with prevention of academic collusion in computer programming     

Ivan Pribela  Mirjana Ivanovi&#;  Zoran Budimac 《British journal of educational technology : journal of the Council for Educational Technology》2009,40(6):1076-1093

This paper discusses Svetovid, cross-platform software that helps instructors to assess the amount of effort put into practical exercises and exams in courses related to computer programming. The software was developed as an attempt at solving problems associated with practical exercises and exams. This paper discusses the design and use of Svetovid system along with the advantages it brings to both students and instructors.  相似文献   

Using the onto-semiotic approach to identify and analyze mathematical meaning when transiting between different coordinate systems in a multivariate context     

Mariana Montiel  Miguel R. Wilhelmi  Draga Vidakovic  Iwan Elstak 《Educational Studies in Mathematics》2009,72(2):139-160

The main objective of this paper is to apply the onto-semiotic approach to analyze the mathematical concept of different coordinate systems, as well as some situations and university students’ actions related to these coordinate systems. The identification of objects that emerge from the mathematical activity and a first intent to describe an epistemic network that relates to this activity were carried out. Multivariate calculus students’ responses to questions involving single and multivariate functions in polar, cylindrical, and spherical coordinates were used to classify semiotic functions that relate the different mathematical objects.  相似文献   

Detection of Catabacter hongkongensis in polluted European water samples     

Francesc Codony  Bárbara Adrados  Leonardo Martín Pérez  Mariana Fittipaldi  Jordi Morató 《Journal of Zhejiang University. Science. B》2009,10(12):867-869

The Catabacteriaceae is a new bacterial family with a unique member: Catabacter hongkongensis is a strictly anaerobic, non-sporulating, Gram-positive coccobacillus that is phylogenetically related to some clostridial clusters. Little is known of its epidemiology and environmental distribution, but the inclusion of its 16S rRNA gene sequence in GenBank has allowed it to be detected qualitatively. As a first approach for prospective surveys, a real-time polymerase chain reaction (PCR) procedure to identify C. hongkongensis has been developed. The presence of Catabacteriaceae in 29 water bodies subjected to possible human or animal impact has been investigated. Four of them were positive. The results confirm that highly polluted water can contain C. hongkongensis.  相似文献   

A brief history of family life education in Romania     

Mariana Momanu  Nicoleta Laura Popa 《Paedagogica Historica: International Journal of the History of Education》2018,54(3):266-286

Starting from the state of conceptual diversity, semantic ambiguity, and poor connection of family life education practices to current policies and theoretical models in Romania, our study aims at understanding the underlying meanings of these issues by recourse to the history of approaches in the field. To this purpose, we carried out a qualitative historical research, based on the thematic analysis of a set of educational works produced between the sixteenth century, when the first Romanian texts were written, and the present time. Primary historical sources are supplemented with reliable secondary sources, while the criteria used for the selection of texts were their relevance to family life education (FLE), and the notoriety of the works in the corresponding historical periods. As in western countries, the concept of FLE was coined in Romania at the beginning of the twentieth century, when the family education discourse was outlined, but the roots of the field can be traced even in the first printed texts. Although marked by strong moral and religious emphases during pre-modernity, FLE has entered the slow process of secularisation and evolved from the perspective of political, social, and moral reconstruction goals of modern Romania. However, FLE’s goals and contents were redefined during Communism, and the discrepancies between discourses, practices, and realities compromised the functionality of the pedagogical model promoted at the time. A unitary definition of FLE in relation to Romanian contemporary families’ needs requires reconciliation with historical, cultural, and educational premises, as well as a careful contextualisation of western models and practices.  相似文献   

The AGTR2 rs11091046 (A>C) polymorphism and power athletic status in top-level Brazilian athletes     

João Paulo Limongi França Guilherme  Mariana Sussi Silva  Rômulo Bertuzzi  Antonio Herbert Lancha Junior 《Journal of sports sciences》2018,36(20):2327-2332

The main purpose of this study was to investigate if the rs11091046 (A>C) polymorphism in AGTR2 gene is associated with athletic status in top-level athletes from Brazil. Since the AGTR2 gene is located on the X chromosome, the case-control association study was done separately for women and men. The female cohort was composed of 205 athletes and 241 non-athletes, and the male cohort was composed of 419 athletes and 490 non-athletes. We did not identify an association between the C-allele and the endurance phenotype. However, power athletes had a higher frequency of the A-allele. In women, A/A genotype was overrepresented in international-level power group compared with non-athletes or international-level endurance athletes (23.2% vs. 16.6% or 8.8%, respectively; p < 0.05). In men, the A-allele frequency observed in power athletes or international-level power athletes was statistically different from that observed in non-athletes (51.6% or 57.8% vs. 40.4%; p < 0.009). Furthermore, men sprinters with the A-allele showed significantly faster personal best times for the 100 m than those with the C-allele (10.56 ± 0.32 s vs. 10.93 ± 0.49 s; p < 0.02). In conclusion, it was found that the AGTR2 A-allele is a candidate genetic marker for top-level power athletes.  相似文献   

Diagnostic accuracy of heart fatty acid binding protein (H-FABP) and glycogen phosphorylase isoenzyme BB (GPBB) in diagnosis of acute myocardial infarction in patients with acute coronary syndrome     

Cubranic Z  Madzar Z  Matijevic S  Dvornik S  Fisic E  Tomulic V  Kunisek J  Laskarin G  Kardum I  Zaputovic L 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(2):225-236

Introduction:

This study aimed to assess whether heart fatty acid-binding protein (H-FABP) and glycogen phosphorylase isoenzyme BB (GPBB) could be used for the accurate diagnosis of acute myocardial infarction (AMI) in acute coronary syndrome (ACS) patients.

Materials and methods:

The study included 108 ACS patients admitted to a coronary unit within 3 h after chest pain onset. AMI was distinguished from unstable angina (UA) using a classical cardiac troponin I (cTnI) assay. H-FABP and GPBB were measured by ELISA on admission (0 h) and at 3, 6, 12, and 24 h after admission; their accuracy to diagnose AMI was assessed using statistical methods.

Results:

From 92 patients with ACS; 71 had AMI. H-FABP and GPBB had higher peak value after 3 h from admission than cTnI (P = 0.001). Both markers normalized at 24 h. The area under the receiver operating characteristic curves was significantly greater for both markers in AMI patients than in UA patients at all time points tested, including admission (P < 0.001). At admission, the H-FABP (37%) and GPBB (40%) sensitivities were relatively low. They increased at 3 and 6 h after admission for both markers and decreased again after 24 h. It was 40% for H-FABP and approximately 2-times lower for GPBB (P < 0.01). In AMI patients, both biomarkers had similar specificities, positive- and negative-predictive values, positive and negative likelihood ratios, and risk ratios for AIM.

Conclusion:

H-FABP and GPBB can contribute to early AMI diagnosis and can distinguish AMI from UA.  相似文献   

National vs. international journals: views of medical professionals in Croatia     

Dario SAMBUNJAK  Mirjana HUIĆ  Darko HREN  Milica KATIĆ  Ana MARUŠIĆ  Matko MARUŠIĆ 《Learned Publishing》2009,22(1):57-70

Scholarly journals, especially in non‐English‐speaking countries, may perform very different functions depending on whether they are published for national or international audiences. Four hundred and sixty‐six academic physicians and non‐academic general practitioners in Croatia were surveyed on their knowledge about two Croatian medical journals: Lije?ni?ki vjesnik (published in Croatian) and Croatian Medical Journal (published in English). The physicians were also surveyed about the importance of all national and international journals published in Croatia, and the types of articles they thought should be published in these journals. More respondents rated national (n = 329, 72.6%) than international journals (n = 275, 63.5%, P < 0.001, Wilcoxon test) as very important for the medical profession. On the other hand, publishing in international journals was more often rated as important than publishing in national journals (n = 184, 42.5% vs. n = 125, 27.8%; P < 0.001, Wilcoxon test). Guidelines for clinical practice were rated as the most important publication item in national journals, and original scientific articles in international journals.  相似文献