The development of numeracy in England and Slovenia

The Third International Mathematics and Science Study (TIMSS) placed Slovene 9 year olds significantly above the international mean in mathematics and English 9 year olds significantly below. As the project to be described here shows, however, such findings can mask finer differences in numerical abilities and problem-solving which qualitative analysis can reveal. While performance in arithmetic tasks of English 6 year olds was superior to Slovene pre-schoolers of the same age, at 7 years Slovene pupils had caught up and between 8 and 11 years forged ahead. By contrast, Slovene pupils were not quite so successful at problem-solving tasks in comparison with the English sample. Possible improvements, in the first place, might be obtained by a careful synthesis of curricula and instructional strategies but is this too simple a solution? A major goal of this paper will be to provide insight into the limitations of large-scale international studies and research methodologies as well as advocate qualitative approaches which, if not challenging such studies certainly complement and enrich them by setting out to answer another set of research questions. This paper also raises important questions about cultural differences which influence the aims and philosophy of education both directly and indirectly.     

Arginase Activity and Lecithin/Sphingomyelin (L/S) Ratio in the Amniotic Fluid of Pregnant Women

Arginase activity is important in polyamines and nitric oxide production which are required for the normal growth of placenta and embryo. A considerable arginase activity is observed in amniotic fluid in women at the end of pregnancy. Lecithin to sphingomyelin (L/S) ratio is widely used in order to assess fetal lung immaturity and prevention of neonatal respiratory distress syndrome, the major cause of neonatal morbidity and mortality. The purpose of our study was to determine if there is a relationship between arginase activity and L/S ratio in amniotic fluid. The study included 170 pregnant women, 18–43 years old, with normal and pathological pregnancy. The arginase activity was measured on the basis of the determination of the amount of liberated ornithine from arginine as substrate. The L/S ratio was done by using a thin layer chromatography. Increased level of arginase activity correlates with the fetal lung maturity. Arginase activity and L/S values may be useful biochemical data, for intrauterine baby maturity.     

Evaluation of the BD Vacutainer? RST blood collection tube for routine chemistry analytes: clinical significance of differences and stability study

Introduction:

Preanalytical variables account for most of laboratory errors. There is a wide range of factors that affect the reliability of laboratory report. Most convenient sample type for routine laboratory analysis is serum. BD Vacutainer^® Rapid Serum Tube (RST) (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) blood collection tube provides rapid clotting time allowing fast serum separation. Our aim was to evaluate the comparability of routine chemistry parameters in BD Vacutainer^® RST blood collection tube in reference with the BD Vacutainer^® Serum Separating Tubes II Advance Tube (SST) (Becton, Dickinson and Company, Franklin Lakes, NJ, USA).

Materials and methods:

Blood specimens were collected from 90 participants for evaluation on its results, clotting time and stability study of six routine biochemistry parameters: glucose (Glu), aspartate aminotransferase (AST), alanine aminotransferase (ALT), calcium (Ca), lactate dehidrogenase (LD) and potassium (K) measured with Olympus AU2700 analyzer (Beckman Coulter, Tokyo, Japan). The significance of the differences between samples was assessed by paired t-test or Wilcoxon Matched-Pairs Rank test after checking for normality.

Results:

Clotting process was significantly shorter in the RSTs compared to SSTs (2.49 min vs. 19.47 min, respectively; P < 0.001). There was a statistically significant difference between the RST and SST II tubes for glucose, calcium and LD (P < 0.001). Differences for glucose and LD were also clinically significant. Analyte stability studies showed that all analytes were stable for 24 h at 4 °C.

Conclusions:

Most results (except LD and glucose) from RST are comparable with those from SST. In addition, RST tube provides shorter clotting time.     

Differential electronic detector to monitor apoptosis using dielectrophoresis-induced translation of flowing cells (dielectrophoresis cytometry)

The instrument described here is an all-electronic dielectrophoresis (DEP) cytometer sensitive to changes in polarizability of single cells. The important novel feature of this work is the differential electrode array that allows independent detection and actuation of single cells within a short section ( ～ 300?μm) of the microfluidic channel. DEP actuation modifies the altitude of the cells flowing between two altitude detection sites in proportion to cell polarizability; changes in altitude smaller than 0.25 μm can be detected electronically. Analysis of individual experimental signatures allows us to make a simple connection between the Clausius-Mossotti factor (CMF) and the amount of vertical cell deflection during actuation. This results in an all-electronic, label-free differential detector that monitors changes in physiological properties of the living cells and can be fully automated and miniaturized in order to be used in various online and offline probes and point-of-care medical applications. High sensitivity of the DEP cytometer facilitates observations of delicate changes in cell polarization that occur at the onset of apoptosis. We illustrate the application of this concept on a population of Chinese hamster ovary (CHO) cells that were followed in their rapid transition from a healthy viable to an early apoptotic state. DEP cytometer viability estimates closely match an Annexin V assay (an early apoptosis marker) on the same population of cells.     

Verification policies in Croatian medical biochemistry laboratories: a survey of the practice

IntroductionThe aim of this study was to screen practices used in verification procedures for methods/analysers among medical biochemistry laboratories (MBLs) in Croatia. We hypothesized that these procedures differ widely from laboratory to laboratory and wanted to gather specific data on steps used in the verification workflow.Materials and methodsIn order to obtain data, an online survey was conducted. The survey, divided in two sections, contained 29 questions and statements addressing general characteristics and specific steps of the verification workflow of each individual MBL. The survey was disseminated among managers of all MBLs in Croatia.ResultsA total of 108/196 (55%) laboratories participated in the survey. Forty nine MBLs were excluded from the second part of the survey: 14 have not implemented verification procedures, and 35 MBLs due to the absence of answers. The most relevant results of the second part of the survey showed that: 18/59 (0.31) of the responding MBLs have difficulties when defining acceptance criteria, 27/59 (0.46) used the Clinical and Laboratory Standards Institute protocol for precision estimation; the majority of MBLs used a median of 20 samples for method/analyser comparisons and estimated bias using internal quality control samples; reference intervals provided by external sources are mainly adopted; 60% of MBLs do not include linearity verification in their protocol and do not use the national document for the estimation of measurement uncertainty.ConclusionsHeterogeneous verification protocols are routinely utilized across Croatian MBLs which clearly confirms that a national document might help in the harmonization of verification procedures.     

Lipoproteins and cholesterol homeostasis in paediatric nephrotic syndrome patients

IntroductionThe aim of this study was to investigate lipoprotein particle distributions and the likelihood of achieving cholesterol homeostasis in the remission phase of nephrotic syndrome (NS) in paediatric patients. We hypothesized that lipoprotein particle distributions moved toward less atherogenic profile and that cholesterol homeostasis was achieved.Materials and methodsThirty-three children, 2 to 9 years old with NS were recruited. Blood sampling took place both in the acute phase and during remission. Serum low-density lipoprotein particles (LDL) and high-density lipoprotein particles (HDL) were separated using non-denaturing polyacrylamide gradient gel (3-31%) electrophoresis. Serum non-cholesterols sterols (NCSs), desmosterol, lathosterol, 7-dehydrocholesterol (7-DHC), campesterol and β-sitosterol were measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).ResultsAll patients had desirable serum HDL cholesterol concentrations during remission. The dominant lipoprotein diameters and LDL subclass distribution did not change significantly during follow-up. In contrast, HDL lipoprotein particle distribution shifted towards larger particles. The absolute concentration of desmosterol was significantly lower during remission (P = 0.023). β-sitosterol concentration markedly increased during remission (P = 0.005). Desmosterol/β-sitosterol (P < 0.001) and 7-DHC/β-sitosterol (P = 0.005) ratios significantly declined during disease remission.ConclusionsFavourable changes in the serum lipid profiles, HDL particle subclass distribution and cholesterol metabolism in paediatric patients with NS during remission took place. For the first time, we found that cholesterol homeostasis changed in favour of increased cholesterol absorption during disease remission. Nevertheless, complete cholesterol homeostasis was not achieved during disease remission.     

The reasons students choose teaching professions

The purpose of the paper is to present the reasons students at the Faculty of Education in Maribor, Slovenija, chose pedagogy for their study direction, and therefore becoming a teacher. A total 237 second‐year students of the academic year 2003/04 were included in the research. Of the five groups of reasons for choosing this program (altruistic, material, self‐realization and alternative, and reasons arising from aspiration stereotype), students most often asserted self‐realization, including: teaching provides a useful public function for the whole society; as a teacher, I can be an example to children and young people; this profession will give me a chance for professional development during my whole career; and teaching will enable me to use all my abilities (and talents—for example, music, verbal, dancing, etc.) Important differences were found to exist between students of different disciplines.     

Establishing paediatric reference intervals for thyroid function tests in Croatian population on the Abbott Architect i2000

IntroductionEvaluation of thyroid function is often requested and therefore defining paediatric reference intervals (RIs) is of vital importance. Currently, there is a distinct lack of paediatric RIs for thyroid function tests in Croatia. Thus, we established RIs for thyroid stimulating hormone (TSH), total triiodothyronine (TT3), total thyroxine (TT4), free triiodothyronine (FT3) and free thyroxine (FT4) in the Croatian paediatric population.Materials and methodsReference intervals were calculated from 397 apparently healthy children, aged from 2 days to < 19 years. Serum samples were analysed for thyroid function tests on the Abbott Architect i2000. Age- and sex-specific 95% RIs with 90% confidence intervals were established according to Clinical and Laboratory Standards Institute guidelines. To express the magnitude of sex and age variation, standard deviation ratio (SDR) was calculated using two-level nested ANOVA. The criterion for considering partitioning reference values was set to SDR > 0.3.ResultsAll thyroid function tests required age partitioning, confirmed by SDR above 0.3. There was no need for sex partitioning, confirmed by SDR below 0.3. Still, FT3 was partitioned due to visually noticeable sex related difference for the oldest group (12 years to < 19 years).ConclusionThis is the first study to establish RIs for thyroid function tests in the Croatian paediatric population. We propose RIs for widely used Abbott platform, thus giving laboratories method- and population-specific paediatric RIs for thyroid function tests that should improve clinical test interpretation.     

Cooperative learning and team culture in schools: Conditions for teachers’ professional development

The study done in Slovenia examined grammar and elementary teachers’ perceptions of cooperative learning. The sample consisted of 542 Slovene elementary and grammar school teachers, who teach Slovene. The main question of the research was how teachers assess the value of group learning in comparison to individual forms of learning. From their perceptions, we can draw conclusions about their development, the introduction of group work within lessons and about the encouragement of pupils towards collaborative learning. The main finding of the research is that elementary school teachers place greater importance on group learning than grammar school teachers. In addition, when teachers are grouped according to their years of experience (seniority), there are differences in their assessment of group learning. However, it is not possible to get a linear pattern from the results (e.g. showing that years of experience do or do not contribute to the perception of the importance of group learning), a finding which supports the critical opinion that teachers’ experience depends not only on the quantity (years of experience), but also on the quality of experience.