Secondary structure effects on DNA hybridization kinetics: a solution versus surface comparison

The hybridization kinetics for a series of designed 25mer probe–target pairs having varying degrees of secondary structure have been measured by UV absorbance and surface plasmon resonance (SPR) spectroscopy in solution and on the surface, respectively. Kinetic rate constants derived from the resultant data decrease with increasing probe and target secondary structure similarly in both solution and surface environments. Specifically, addition of three intramolecular base pairs in the probe and target structure slow hybridization by a factor of two. For individual strands containing four or more intramolecular base pairs, hybridization cannot be described by a traditional two-state model in solution-phase nor on the surface. Surface hybridization rates are also 20- to 40-fold slower than solution-phase rates for identical sequences and conditions. These quantitative findings may have implications for the design of better biosensors, particularly those using probes with deliberate secondary structure

Secondary structure effects on DNA hybridization kinetics: a solution versus surface comparison

The hybridization kinetics for a series of designed 25mer probe–target pairs having varying degrees of secondary structure have been measured by UV absorbance and surface plasmon resonance (SPR) spectroscopy in solution and on the surface, respectively. Kinetic rate constants derived from the resultant data decrease with increasing probe and target secondary structure similarly in both solution and surface environments. Specifically, addition of three intramolecular base pairs in the probe and target structure slow hybridization by a factor of two. For individual strands containing four or more intramolecular base pairs, hybridization cannot be described by a traditional two-state model in solution-phase nor on the surface. Surface hybridization rates are also 20- to 40-fold slower than solution-phase rates for identical sequences and conditions. These quantitative findings may have implications for the design of better biosensors, particularly those using probes with deliberate secondary structure

A critical evaluation of the usefulness of a coding scheme to categorise levels of reflective thinking

The use of reflective learning journals to encourage higher order learning outcomes is a growing area in higher education research and practice. However, without a unified and clear definition of reflection, identifying and assessing reflection is problematic for educators. In an attempt to address this issue Kember et al. (1999) devised a coding scheme based on the work of Mezirow (1991), to identify and assess levels of reflective thinking in students’ written journals. We evaluated the usefulness of this coding scheme in a business education context. Findings revealed that the scheme was useful in identifying categories of reflective thinking. Initial inter-coder agreement ranged from 50-79%. On average, 65% of the journal content was coded as non-reflection and 35% as reflection. A further outcome of the research was to refine the coding scheme and to provide suggestions for its application in teaching practice

Production and detection of doubly charmed tetraquarks

The feasibility of tetraquark detection is studied. For the cc\bar{u}\bar{d} tetraquark we show that in present (SELEX, Tevatron, RHIC) and future facilities (LHCb, ALICE) the production rate is promising and we propose some detectable decay channels.Comment: 6 pages, 5 figure

Policy for sustainable entrepreneurship: a crowdsourced framework

Sustainable entrepreneurship—entrepreneurship with social and ecological gains as well as economic ones—has the potential to play a significant role in addressing societal and environmental challenges. However, sustainability and entrepreneurship have hitherto been addressed through separate policy regimes, and it is not clear how policymakers can encourage sustainable entrepreneurship specifically. The authors develop a policy framework for sustainable entrepreneurship, using an open innovation approach with policymakers, business executives, academics, entrepreneurs and other relevant actors, including an online crowdsourcing event with 150 participants. The framework incorporates five policy domains: creating awareness and skills; building networks; funding and investing; measuring impact and performance; and innovating government. The article proposes a modified version of the multi-level perspective (MLP) on how socio-technical transitions occur, since the findings suggest that policy can catalyze the facilitation and aggregation of innovations coming from the niche level, thereby evolving the socio-technical regime, in addition to the role of policy described in earlier work in stabilizing the socio-technical regime. Contributions to entrepreneurship policy literature include the policy domain of measuring impact and performance, as appropriate success measures are non-trivial in a triple bottom line environment, and the potential for open policy innovation in entrepreneurship policy. Contributions to sustainability policy literature include the requirements for support mechanisms and capacity building to empower individuals to contribute as innovators and entrepreneurs and not just consumers. The sustainable entrepreneurship framework can be applied by policymakers to develop context-specific policies: this is illustrated with a worked example of EU policy recommendations. The paper also outlines a method for crowdsourcing policy innovations

Policy for sustainable entrepreneurship: a crowdsourced framework

Sustainable entrepreneurship—entrepreneurship with social and ecological gains as well as economic ones—has the potential to play a significant role in addressing societal and environmental challenges. However, sustainability and entrepreneurship have hitherto been addressed through separate policy regimes, and it is not clear how policymakers can encourage sustainable entrepreneurship specifically. The authors develop a policy framework for sustainable entrepreneurship, using an open innovation approach with policymakers, business executives, academics, entrepreneurs and other relevant actors, including an online crowdsourcing event with 150 participants. The framework incorporates five policy domains: creating awareness and skills; building networks; funding and investing; measuring impact and performance; and innovating government. The article proposes a modified version of the multi-level perspective (MLP) on how socio-technical transitions occur, since the findings suggest that policy can catalyze the facilitation and aggregation of innovations coming from the niche level, thereby evolving the socio-technical regime, in addition to the role of policy described in earlier work in stabilizing the socio-technical regime. Contributions to entrepreneurship policy literature include the policy domain of measuring impact and performance, as appropriate success measures are non-trivial in a triple bottom line environment, and the potential for open policy innovation in entrepreneurship policy. Contributions to sustainability policy literature include the requirements for support mechanisms and capacity building to empower individuals to contribute as innovators and entrepreneurs and not just consumers. The sustainable entrepreneurship framework can be applied by policymakers to develop context-specific policies: this is illustrated with a worked example of EU policy recommendations. The paper also outlines a method for crowdsourcing policy innovations

Electrophilic nitroalkene-tocopherol derivatives: synthesis, physicochemical characterization and evaluation of anti-inflammatory signaling responses

Inflammation plays a major role in the onset and development of chronic non-communicable diseases like obesity, cardiovascular diseases and cancer. Combined, these diseases represent the most common causes of death worldwide, thus development of novel pharmacological approaches is crucial. Electrophilic nitroalkenes derived from fatty acids are formed endogenously and exert anti-inflammatory actions by the modification of proteins involved in inflammation signaling cascades. We have developed novel nitroalkenes derived from α-tocopherol aiming to increase its salutary actions by adding anti-inflammatory properties to a well-known nutraceutical. We synthesized and characterized an α-tocopherol-nitroalkene (NATOH) and two hydrosoluble analogues derived from Trolox (NATxME and NATx0). We analyzed the kinetics of the Michael addition reaction of these compounds with thiols in micellar systems aiming to understand the effect of hydrophobic partition on the reactivity of nitroalkenes. We studied NATxME in vitro showing it exerts non-conventional anti-inflammatory responses by inducing Nrf2-Keap1-dependent gene expression and inhibiting the secretion of NF-κB dependent pro-inflammatory cytokines. NATxME was also effective in vivo, inhibiting neutrophil recruitment in a zebrafish model of inflammation. This work lays the foundation for the rational design of a new therapeutic strategy for the prevention and treatment of metabolic and inflammation-related disease

Model of success : World Association for the Advancement of Veterinary Parasitology African Foundation (1997-2019)

No abstract available.http://www.jsava.co.za/index.php/jsavapm2020Veterinary Tropical Disease

FGFR3 expression in primary and metastatic urothelial carcinoma of the bladder

While fibroblast growth factor receptor 3 (FGFR3) is frequently mutated or overexpressed in nonmuscle-invasive urothelial carcinoma (UC), the prevalence of FGFR3 protein expression and mutation remains unknown in muscle-invasive disease. FGFR3 protein and mRNA expression, mutational status, and copy number variation were retrospectively analyzed in 231 patients with formalin-fixed paraffin-embedded primary UCs, 33 metastases, and 14 paired primary and metastatic tumors using the following methods: immunohistochemistry, NanoString nCounterTM, OncoMap or Affymetrix OncoScanTM array, and Gain and Loss of Analysis of DNA and Genomic Identification of Significant Targets in Cancer software. FGFR3 immunohistochemistry staining was present in 29% of primary UCs and 49% of metastases and did not impact overall survival (P = 0.89, primary tumors; P = 0.78, metastases). FGFR3 mutations were observed in 2% of primary tumors and 9% of metastases. Mutant tumors expressed higher levels of FGFR3 mRNA than wild-type tumors (P < 0.001). FGFR3 copy number gain and loss were rare events in primary and metastatic tumors (0.8% each; 3.0% and 12.3%, respectively). FGFR3 immunohistochemistry staining is present in one third of primary muscle-invasive UCs and half of metastases, while FGFR3 mutations and copy number changes are relatively uncommon