Shareholder returns and the exploration-exploitation dilemma: R&D announcements by biotechnology firms

We explore a financial returns dimension of the exploration-exploitation dilemma. Using 1277 R&D announcements by 178 listed bio-pharmaceutical firms, we examine whether investors are myopic along the continuum of exploration (patenting and preclinical trials) to exploitation (human clinical trials and NDA). We find that investors respond positively at every stage, but there are differences between small and large firms. For small firms exploration is favored, provided it is focused. For large firms, there is value in both exploration and exploitation. Projects which are part of an alliance are no more likely to generate abnormal returns. Policy implications are discussed.     

An analysis of assignment completion and accuracy across time under fixed, variable, and extended token exchange periods in a classroom token economy

This research investigated the effects of employing fixed, variable, and extended token exchange periods for backups on the completion and quality of daily assignments of a total fifth- and sixth-grade class. The results indicated a higher percentage of assignments was completed when the number of days between point exchanges was variable, and that performance was maintained when the number of school days between point exchanges was gradually increased. The overall accuracy on assignments was high, but varying, and did not appear to be under the systematic control of the experimental procedures. Data for all pupils indicated that there were individual differences as to the effects of the various token (point) exchange procedures. Pupils with inconsistent assignment completion during Fixed Exchange Conditions (Fixed Period (FP-I, -II, -III) increased their assignment completion during the Variable Token Exchange Procedures (Variable Period (VP)-I, -II, -III). Thus, the variable sequencing of the number of days should be an important consideration in any effort to maintain the positive effects of token-reinforcement systems within classroom settings.     

Primary Teachers’ Reflections on Inquiry- and Context-Based Science Education

Inquiry- and context-based teaching strategies have been proven to stimulate and motivate students’ interests in learning science. In this study, 12 teachers reflected on these strategies after using them in primary schools. The teachers participated in a continuous professional development (CPD) programme. During the programme, they were also introduced to a teaching model from a European project, where inquiry- and context-based education (IC-BaSE) strategies were fused. The research question related to teachers’ reflections on these teaching strategies, and whether they found the model to be useful in primary schools after testing it with their students. Data collection was performed during the CPD programme and consisted of audio-recorded group discussions, individual portfolios and field notes collected by researchers. Results showed that compared with using only one instructional strategy, teachers found the new teaching model to be a useful complement. However, their discussions also showed that they did not reflect on choices of strategies or purposes and aims relating to students’ understanding, or the content to be taught. Before the CPD programme, teachers discussed the use of inquiry mainly from the aspect that students enjoy practical work. After the programme, they identified additional reasons for using inquiry and discussed the importance of knowing why inquiry is performed. However, to develop teachers’ knowledge of instructional strategies as well as purposes for using certain strategies, there is need for further investigations among primary school teachers.     

Why Inquiry? Primary Teachers’ Objectives in Choosing Inquiry- and Context-Based Instructional Strategies to Stimulate Students’ Science Learning

Studies have shown that there is a need for pedagogical content knowledge among science teachers. This study investigates two primary teachers and their objectives in choosing inquiry- and context-based instructional strategies as well as the relation between the choice of instructional strategies and the teachers’ knowledge about of students’ understanding and intended learning outcomes. Content representations created by the teachers and students’ experiences of the enacted teaching served as foundations for the teachers’ reflections during interviews. Data from the interviews were analyzed in terms of the intended, enacted, and experienced purposes of the teaching and, finally, as the relation between intended, enacted, and experienced purposes. Students’ experiences of the teaching were captured through a questionnaire, which was analyzed inductively, using content analysis. The results show that the teachers’ intended teaching objectives were that students would learn about water. During the enacted teaching, it seemed as if the inquiry process was in focus and this was also how many of the students experienced the objectives of the activities. There was a gap between the intended and experienced objectives. Hardly any relation was found between the teachers’ choice of instructional strategies and their knowledge about students’ understanding, with the exception that the teacher who also added drama wanted to support her students’ understanding of the states of water.     

Inflammatory and apoptotic signalling pathways and concussion severity: a genetic association study

The objective was to investigate the relationship between IL-1B rs16944, IL-6 rs1800795, and CASP8 rs3834129 genetic polymorphisms and concussion severity. Rugby players from high school, senior amateur, and professional teams completed a concussion severity questionnaire and donated a DNA sample. Participants (n = 163) were split into symptom severity groups around the median number and duration of symptoms. The frequency of participants with high symptom counts (more than five symptoms) increased across the IL-1B (C/C: 35%; C/T: 51%; T/T: 56%; P = 0.047) and the IL-6 (C/C: 31%; C/G: 44%; G/G: 58%; P = 0.027) genotypes. The C–C inferred interleukin allele construct frequency, created from combining the IL-1B and IL-6 genotype data, was lower in participants reporting a high symptom count (18%), compared to those with a low symptom count (fewer than six symptoms, 36%, P = 0.002). Similarly, the C–C inferred interleukin allele construct frequency was lower in those reporting prolonged symptom duration (more than one week, 16%), as opposed to short symptom duration (less than one week, 34%, P = 0.015). This study provides evidence of novel inflammatory pathway genetic associations with concussion severity, which supports the hypothesis implicating neuroinflammation in the development of concussion symptoms.     

A hybrid microfluidic platform for cell-based assays via diffusive and convective trans-membrane perfusion

We present a novel 3D hybrid assembly of a polymer microfluidic chip with polycarbonate track-etched membrane (PCTEM) enabling membrane-supported cell culture. Two chip designs have been developed to establish either diffusive or convective reagent delivery using the integrated PCTEM. While it is well suited to a range of cell-based assays, we specifically employ this platform for the screening of a common antitumor chemotoxic agent (mitomycin C – MMC) on the HL60 myeloid leukemia cell line. The toxic activity of MMC is based on the generation of severe DNA damage in the cells. Using either mode of operation, the HL60 cells were cultured on-chip before, during, and after exposure to MMC at concentrations ranging from 0 to 50 μM. Cell viability was analysed off-chip by the trypan blue dye exclusion assay. The results of the on-chip viability assay were found to be consistent with those obtained off-chip and indicated ca. 40% cell survival at MMC concentration of 50 μM. The catalogue of capabilities of the here described cell assay platform comprises of (i) the culturing of cells either under shear-free conditions or under induced through-membrane flows, (ii) the tight time control of the reagent exposure, (iii) the straightforward assembly of devices, (iv) the flexibility on the choice of the membrane, and, prospectively, (v) the amenability for large-scale parallelization.     

Cytokine responses to resistance training in people with multiple sclerosis

Exercise for individuals with multiple sclerosis (MS) has been shown to improve cardiovascular function, increase strength and endurance, and reduce fatigue. The impact of exercise on immune function in the disease, however, remains mostly unexplored. Ten female MS patients participated in an 8 week programme of twice-weekly progressive resistance training, with pre- and post-training assessment of serum concentrations of cytokines IL-2, IL-4, IL-6, IL-10, CRP, TNF-alpha and IFN-gamma. After training, IL-4, IL-10, CRP and IFN-gamma showed statistically reduced resting concentrations in blood, while TNF-alpha showed non-significant reductions and IL-2 and IL-6 remained unchanged. These results suggest that progressive resistance training may have an impact on cytokine concentrations in individuals with MS and should be confirmed in studies with stronger statistical power. The impact of these changes on overall immune function in MS and on disease status and prognosis remains to be determined.     

It's a Holiday!!

This article studies various holiday distributions, the most interesting one being Easter. Gauss’ Easter algorithm and Microsoft Excel are used to determine that the Easter distribution can be closely approximated by the convolution of two well‐known uniform distributions.