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221.
222.
Giuseppe Lippi Mario Plebani 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
At the down of the third millennium, it is rather misleading to consider the “whole population” as a conceptual entity, whereby the population is actually composed by single individuals, who differ broadly in terms of age, sex, ethnic origin, occupation, health, wellbeing, lifestyle and risk factors. While reaffirming strongly that laboratory medicine shall aim to provide data that could be translated into actionable information on “BOTH” an individual and universal level, we confute and refuse the naive and too simplistic approach that the common beneficence shall always be prioritized over the individual good, since the common good is just the sum of many individual beneficences. 相似文献
223.
Jeffery H. Marshall Claudia R. Aguilar Mario Alas Renán Rápalo Castellanos Levi Castro Ramón Enamorado Esther Fonseca 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2014,60(1):51-77
Honduras has made steady progress in expanding post-primary school coverage in recent years, but many rural communities still do not provide a middle (lower secondary) school. As a result, Honduras has implemented a number of middle school alternative programmes designed to meet the needs of at-risk populations throughout the country. This article analyses dropout in three of the four main alternative lower secondary school programmes in Honduras over a three-year period for a cohort of roughly 5,500 students. The results show that these programmes are indeed reaching a vulnerable population in the country, but dropout rates are generally very high – upwards of 50 per cent in some cases – between Grades 7 and 9. Furthermore, even in the control school comparison samples made up of formal lower secondary schools, about 25 per cent of children leave school between Grades 7 and 9. The authors’ analysis includes propensity score matching (PSM) methods that make more focused comparisons between students in alternative programmes and control samples. These results show that dropout rates in alternative programmes are not much different than in control schools, and only significant in one programme comparison, when taking into account family background characteristics like socioeconomic status (SES). Multivariate analysis within alternative programme samples finds that attrition is lower in those learning centres which have adopted key features of formal schools, such as university-educated teachers. The results highlight the tremendous variation in the alternative middle school sector in terms of programme features, school quality and student outcomes, as well as the challenges of expanding this sector to meet the growing demand for lower secondary schooling in Honduras. 相似文献
224.
Students’ satisfaction with their university and course is of fundamental importance to retain students and promote their positive worth-of-mouth. The objective of this research is to analyse the level of efficiency of Portuguese public universities, according to the expectations and satisfaction of their students. To accomplish the objective, this article uses data envelopment analysis methodology. As our unit of analysis, we selected the faculties making up the universities researched. The analytical input came from the expectations of 1669 students regarding their study programme and their universities. The outputs stem from their satisfaction with their study programmes and their universities. We conclude that university practices do not currently guarantee efficiency. We also observe that efficiency in the relationship between expectations and general satisfaction with the study programme does not represent efficiency in the relationship between expectations and general satisfaction with the university, and vice versa. 相似文献
225.
More than 20 years ago, electrical impedance spectroscopy (EIS) was proposed as a potential characterization method for flow cytometry. As the setup is comparably simple and the method is label-free, EIS has attracted considerable interest from the research community as a potential alternative to standard optical methods, such as fluorescence-activated cell sorting (FACS). However, until today, FACS remains by and large the laboratory standard with highly developed capabilities and broad use in research and clinical settings. Nevertheless, can EIS still provide a complement or alternative to FACS in specific applications? In this Perspective, we will give an overview of the current state of the art of EIS in terms of technologies and capabilities. We will then describe recent advances in EIS-based flow cytometry, compare the performance to that of FACS methods, and discuss potential prospects of EIS in flow cytometry. 相似文献
226.
This paper presents a simple-to-construct, low dead volume pump capable of generating a wide range of positive and negative pressures for microfluidic applications. The pump generates pressure or vacuum by changing the volume of air confined inside a syringe and is able to generate pressures between -95 and +300 kPa with a resolution as high as 1 Pa. Different from syringe pumps and electrokinetic pumping, which are capable of controlling flow rates only, our pump can be used to generate constant flow rates or constant pressures, which are required for certain applications such as the aspiration of biological cells for biophysical characterization. Compared to syringe pumps, the new pump has almost zero dead volume and does not exhibit pulsatile flows. Additionally, the system does not require electrical power and is cost effective (~$100). To demonstrate the capabilities of the pump, we used it to aspirate osteoblasts (MC3T3-E1 cells) and to determine Young's modulus of the cells, to generate a concentration gradient, and to produce variable-sized droplets in microchannels using hydrodynamic focusing. 相似文献