Evidence of Aberrant Immune Response by Endogenous Double‐Stranded RNAs: Attack from Within

Many innate immune response proteins recognize foreign nucleic acids from invading pathogens to initiate antiviral signaling. These proteins mostly rely on structural characteristics of the nucleic acids rather than their specific sequences to distinguish self and nonself. One feature utilized by RNA sensors is the extended stretch of double‐stranded RNA (dsRNA) base pairs. However, the criteria for recognizing nonself dsRNAs are rather lenient, and hairpin structure of self‐RNAs can also trigger an immune response. Consequently, aberrant activation of RNA sensors has been reported in numerous human diseases. Yet, in most cases, the activating antigens remain unknown. Recent studies have developed sequencing techniques tailored to specifically capture dsRNAs and identified that various noncoding elements in the nuclear and the mitochondrial genome can generate dsRNAs. Here, the identity of endogenous dsRNAs, their recognition by dsRNA sensors, and their implications in the pathogenesis of human diseases ranging from inflammatory to degenerative are presented.     

Removal of Nitrate from Groundwater by Cyanobacteria: Quantitative Assessment of Factors Influencing Nitrate Uptake

The feasibility of biologically removing nitrate from groundwater was tested by using cyanobacterial cultures in batch mode under laboratory conditions. Results demonstrated that nitrate-contaminated groundwater, when supplemented with phosphate and some trace elements, can be used as growth medium supporting vigorous growth of several strains of cyanobacteria. As cyanobacteria grew, nitrate was removed from the water. Of three species tested, Synechococcus sp. strain PCC 7942 displayed the highest nitrate uptake rate, but all species showed rapid removal of nitrate from groundwater. The nitrate uptake rate increased proportionally with increasing light intensity up to 100 μmol of photons m⁻² s⁻¹, which parallels photosynthetic activity. The nitrate uptake rate was affected by inoculum size (i.e., cell density), fixed-nitrogen level in the cells in the inoculum, and aeration rate, with vigorously aerated, nitrate-sufficient cells in mid-logarithmic phase having the highest long-term nitrate uptake rate. Average nitrate uptake rates up to 0.05 mM NO₃⁻ h⁻¹ could be achieved at a culture optical density at 730 nm of 0.5 to 1.0 over a 2-day culture period. This result compares favorably with those reported for nitrate removal by other cyanobacteria and algae, and therefore effective nitrate removal from groundwater using this organism could be anticipated on large-scale operations.     

Using Peer Discussion Facilitated by Clicker Questions in an Informal Education Setting: Enhancing Farmer Learning of Science

Blueberry growers in Maine attend annual Cooperative Extension presentations given by university faculty members. These presentations cover topics, such as, how to prevent plant disease and monitor for insect pests. In 2012, in order to make the sessions more interactive and promote learning, clicker questions and peer discussion were incorporated into the presentations. Similar to what has been shown at the undergraduate level, after peer discussion, more blueberry growers gave correct answers to multiple-choice questions than when answering independently. Furthermore, because blueberry growers are characterized by diverse levels of education, experience in the field etc., we were able to determine whether demographic factors were associated with changes in performance after peer discussion. Taken together, our results suggest that clicker questions and peer discussion work equally well with adults from a variety of demographic backgrounds without disadvantaging a subset of the population and provide an important learning opportunity to the least formally educated members. Our results also indicate that clicker questions with peer discussion were viewed as a positive addition to university-related informal science education sessions.     

Science in the Service of Patients: Lessons from the Past in the Moral Battle for the Future of Medical Education

Medical schools instill a classic moral standoff in which the responsibility for the betterment of the patient stands at odds with the responsibility for the betterment of society. In critical ways, the latter, in the form of a robust research and technology-driven enterprise, has taken precedence over the former, resulting in harm to patients and individual dignity. This tradeoff can be traced to Abraham Flexner, the father of American medical education. In the wake of the Flexner report, American medicine set out on a course of exponential scientific advancement, but the mistreatment of research subjects and the erosion of the doctor-patient relationship in a health care system that is increasingly unaffordable, complex, and impersonal suggest that such progress has come at a price. Recent efforts by medical schools to emphasize humanism in their curricula and admissions processes have shown promise in orienting the values of academic medicine toward the individual patient’s well-being.     

Teaching and Learning with Mobile Technology: A Qualitative Explorative Study about the Introduction of Tablet Devices in Secondary Education

This paper investigates teachers’ and students’ perceptions concerning the impact of using tablet devices for teaching and learning purposes. An explorative focus group study was conducted with teachers (n = 18) and students (n = 39) in a secondary school that has implemented tablet devices since 2012. The general finding of this study shows that the use of tablet devices in the classroom setting has an impact on both teaching and learning practices. The results suggest that teachers can be divided into two categories: the innovative teachers and the instrumental teachers. Innovative teachers attempt to shift from a teacher-centered to a learning-centered approach. They have changed their teaching style by transforming lessons in accordance with the advantages tablet computers can offer. Instrumental teachers seem to use the device as a ‘book behind glass’. The distinction between the two groups has consequences for both the way courses are given and how students experience them. In general, the introduction of tablet devices entails a shift in the way students learn, as the devices provide interactive, media-rich, and exciting new environments. The results of this study indicate that policy makers should consider introducing technical and pedagogical support in order to facilitate both teachers’ and students’ understanding of the full potential of this kind of technology in education.     

Change in kinetic property of M1-type pyruvate kinase from hyperbolic type to sigmoidal type by limited proteolysis with an acid fraction from rabbit liver

An acid extract of rabbit liver contained M1-type pyruvate kinase inactivating activity, and was separated to three fractions. The optimal inactivation of the enzyme with Fraction II (Mr 42,000) was observed at pH 5.5, and this inactivation was completely prevented by leupeptin and antipain, but not by pepstatin. With Fraction III (Mr 22,000), on the other hand, optimal inactivation of the enzyme was observed at pH 8-9, and was not prevented by these inhibitors. The kinetic properties, with phosphoenolpyruvate, of the enzyme were changed from hyperbolic type to sigmoidal type by the limited proteolysis with Fractions II and III. The subunit molecular weight of the enzyme (57,300) was decreased to 55,800 via 56,400 in the former case and to 56,400 in the latter case.     

The Teaching of Psychiatry as Applied to Pediatrics: Proposals Based on a Report Prepared by the Education Committee,Canadian Paediatric Society

With changing patterns of pediatric practice, the practising physician needs to acquire a deeper understanding of the emotional and intellectual development of the child. Skill is also required in the techniques of interviewing and counselling parents, and, with a knowledge of the origin of behavioural disorders, in treating these disorders. The Education Committee of the Canadian Paediatric Society was asked to survey the present teaching of psychiatry as applied to pediatrics in all Canadian medical schools. Based on this survey and other studies, a training program for undergraduate medical students and graduates is proposed.     

Dual-curing resin cement with colour indicator for adhesively cemented restorations to dental tissues: Change of colour by curing and some physical properties

The study was aimed to investigate a color indicator containing dual curing resin composite luting cement and to plot the color change to the time of solidification of the cement. In addition some physical properties were studied. Specimens were made of a dual-cure resin cement (Maxcem Elite™ Chroma, Kerr, Orange, CA, USA) and polymerized by autopolymerization only, or with light initiated polymerization. A spectrophotometer was used to quantify the color change of the cement as plotted with the curing time. The efficacy of the curing process was studied by measuring water sorption and the ultimate flexural properties of the cement. The results showed that the flexural strength of cement after autopolymerization was 27.3 MPa and after light initiated polymerization 48.1 MPa. Young’s modulus of bending was 2089.3 MPa and 3781.5 MPa respectively for the same cement samples. Water sorption after two weeks for the autopolymerization cement samples was −1.12 wt% and for the light initiated polymerization samples 0.56 wt%. Non-parametric Spearman’s correlation was measured for autopolymerized cement samples between variables for color and solidification load (N), which showed a strong correlation between curing process and color change (p < 0.05). There was a correlation between the color change and degree of monomer conversion of the dual curing resin composite luting cement which contained a color indicator system for polymerization reaction. The study also suggested that autopolymerization only resulted in suboptimal polymerization of the cement. By additional light curing considerably higher flexural properties were obtained.