International collaborative follow - up investigation of graduating high school students’ understandings of the nature of scientific inquiry: is progress Being made?

Understandings of the nature of scientific inquiry (NOSI), as opposed to engaging students in inquiry learning experiences, are included in science education reform documents around the world. However, little is known about what students have learned about NOSI during their pre-college school years. The purpose of this large-scale follow-up international project (i.e. 32 countries and regions, spanning six continents and including 3917 students for the high school sample) was to collect data on what exiting high school students have learned about NOSI. Additionally, the study investigated changes in 12th grade students’ NOSI understandings compared to seventh grade (i.e. 20 countries and regions) students’ understandings from a prior investigation [Lederman et al. (2019). An international collaborative investigation of beginning seventh grade students’ understandings of scientific inquiry: Establishing a baseline. Journal of Research in Science Teaching, 56(4), 486–515. https://doi.org/10.1002/tea.21512]. This study documents and discusses graduating high school students’ understandings and compares their understandings to seventh grade students’ understandings of the same aspects of scientific inquiry for each country. It is important to note that collecting data from each of the 130+ countries globally was not feasible. Similarly, it was not possible to collect data from every region of each country. A concerted effort was made, however, to provide a relatively representative picture of each country and the world

Induction of ferritin synthesis in cells infected with Mengo virus.

We have recently identified ferritin as a cellular protein particle whose synthesis is stimulated in mouse or human cells infected by the picornavirus Mengo. Immunoprecipitation of the particle from infected murine L929 cells showed a 4- and 6-fold increase in the intracellular concentrations of H and L apoferritin subunits, respectively. This differential expression altered the H/L subunit ratio from 3.0 in uninfected cells to 2.2 in Mengo virus-infected cells. The induction is not due to an increase in transcription of the apoferritin L and H genes, nor is it due to an increase in stability of the apoferritin mRNAs. At the level of translation, the iron regulatory protein (IRP) remained intact, with similar amounts being detected in uninfected and infected cells. The Mengo virus RNA genome does not compete with the iron regulatory element (IRE) for the binding of IRP, and sequence analysis confirmed that there are no IREs in the virus RNA. The IRE binding activity of IRP in infected cells decreased approximately 30% compared with uninfected cells. The decrease in binding activity could be overcome by the addition of Desferal (deferoxamine mesylate; CIBA) an intracellular iron chelator, which suggests that virus infection causes an increase in intracellular free iron. Electron paramagnetic resonance (EPR) studies have confirmed the increase in free iron in Mengo virus infected cells. The permeability of cells for iron does not change in virus infected cells, suggesting that the induction of ferritin by Mengo virus is due to a change in the form of intracellular iron from a bound to a free state

Complete nucleotide sequence analysis of multidrug-resistance IncA/C plasmid PR55 from Klebsiella pneumoniae isolated in 1969

National audienceObjectives: To determine the complete nucleotide sequence of the multidrug-resistant IncA/C plasmid pR55 from a clinical Klebsiella pneumoniae strain that was isolated from urinary tract infection in 1969 in a French hospital and compare it with those of contemporary emerging IncA/C plasmids. Methods: The plasmid was purified and sequenced using a 454 sequencing approach. After draft assembly, additional PCRs and walking reads were performed for gap closure. Sequence comparisons and multiple alignments with other IncA/C plasmids were done using BLAST algorithm and CLUSTAL W, respectively. Conclusions: IncA/C2 multidrug resistance plasmids possess a broad host-range and have been largely implicated in the dissemination of antibiotic resistance among Enterobacteriaceae from humans and animals. This typical IncA/C2 genetic scaffold appears to carry various multidrug resistance gene arrays and is now also a successful vehicle for spreading of AmpC-like cephalosporinase and metallo-β-lactamase genes such as blaCMY and blaNDM, respectively

Functioning of the hypothalamic-pituitary-adrenal and growth hormone axes in frequently unexplained disorders: Results of a population study

Background: the aim of the study was to test the hypothesis that associations with specific stress systems [hypothalamic–pituitary–adrenal (HPA) and growth hormone (GH) axes] would increase as the number of unexplained disorders increased while accounting for the possible confounding effects of psychosocial factors.Methods: a cross-sectional study identified those reporting chronic widespread pain, irritable bowel syndrome, chronic orofacial pain and chronic fatigue. Of the 1315 subjects, disorder status was available for 1180 (89.7%), of whom 766 (64.9%) reported no disorders, 277 (23.5%) reported one and 137 (11.6%) reported two or more. Eighty subjects were sought from each group for assessment of HPA (morning 8:00 a.m. and evening 10:00 p.m. saliva, and post-dexamethasone serum cortisol levels) and GH [serum insulin-like growth factor 1 (IGF-1) level] axis function. Validated questionnaires informed current psychological state.Results: two hundred twenty-seven subjects participated [79 (35%) with no disorders, 78 (34%) with one disorder and 70 (31%) with two or more disorders]. There were no significant associations (p < 0.05) between individual disorders or an increasing disorder load with any of the neuroendocrine levels measured: saliva/serum cortisol, IGF-1 and dehydroepiandrosterone. Psychosocial factors were independently associated with disorders and with an increasing disorder load: health anxiety p < 0.01, anxiety p < 0.01, depression p < 0.01, life events p = 0.03.Conclusion: although previous studies have shown that stress axis function acts to moderate the risk of onset of some of these disorders, the present study shows that the degree of dysfunction is not correlated with a corresponding increasing load of disorders. The uncertainty surrounding the role of these biomarkers in the aetiology of unexplained disorders needs further investigation

Decline in Decreased Cephalosporin Susceptibility and Increase in Azithromycin Resistance in Neisseria gonorrhoeae, Canada

Antimicrobial resistance profiles were determined for Neisseria gonorrhoeae strains isolated in Canada during 2010–2014. The proportion of isolates with decreased susceptibility to cephalosporins declined significantly between 2011 and 2014, whereas azithromycin resistance increased significantly during that period. Continued surveillance of antimicrobial drug susceptibilities is imperative to inform treatment guidelines