Developing a design framework for laboratory videos in molecular biosciences

BACKGROUND Video-based learning has become increasingly integrated into higher education (Fadde & Vu, 2014). In particular, use of laboratory video expanded for students unable to attend in-person instruction during the pandemic (Delgado, Bhark, & Donahue, 2021; Slade et al., 2021). However, there remains a paucity of standardised guidelines for designing laboratory-training videos. AIMS This project aims to analyse student perceptions and engagement with laboratory video to inform future laboratory video design. METHODS Nine videos were produced to teach core microbiology laboratory skills (e.g. aseptic technique) for a microbiology course (876 students). Video analytics were collected from YouTube Creator Studio between 11/08/2020 to 29/11/2021, with student perceptions on helpfulness of various video design features collected through a survey (7% response rate) and follow-up interviews. RESULTS The percentage of students watching (audience retention) declined throughout a video, with sharp declines in initial and final 5% of video. Audience retention was significantly higher in scenes focused on technique demonstration or written explanations versus speaking instructor (“talking-head”) (p<0.001), and in presence of supplementary text (p<0.001) or illustrations (p<0.001). Similarly, students rated ‘demonstration’ and ‘writing’ as more helpful than ‘talking-head’ (p<0.001), however a variety of design features were rated as helpful. CONCLUSIONS We find a variety of design features are helpful, with student perceptions of helpfulness agreeing with differences in audience retention throughout laboratory-skill videos. REFERENCES Delgado, T., Bhark, S. J., & Donahue, J. (2021). Pandemic Teaching: Creating and teaching cell biology labs online during COVID-19. Biochemistry and Molecular Bioogyl Education, 49(1), 32-37. https://doi:10.1002/bmb.21482 Fadde, P. J., and Vu, P. (2014). Blended online learning: Benefits, challenges, and misconceptions. In Lowenthal, P. R., York, C. S., Richardson, J. C. (Eds.), Online Learning: Common    Misconceptions,    Benefits,    and    Challenges,    Nova    Science    Publishing, Hauppauge, 33-48. Slade, C., Lawrie, G., Taptamat, N., Browne, E., Sheppard, K., & Matthews, K. E. (2021). Insights into how academics reframed their assessment during a pandemic: disciplinary variation and assessment as afterthought. Assessment and Evaluation in Higher Education, 47(4), 588-605. https://doi:10.1080/02602938.2021.193337

Seasonal controls of aragonite saturation states in the Gulf of Maine

Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 122 (2017): 372–389, doi:10.1002/2016JC012373.The Gulf of Maine (GoME) is a shelf region especially vulnerable to ocean acidification (OA) due to natural conditions of low pH and aragonite saturation states (Ω-Ar). This study is the first to assess the major oceanic processes controlling seasonal variability of the carbonate system and its linkages with pteropod abundance in Wilkinson Basin in the GoME. Two years of seasonal sampling cruises suggest that water-column carbonate chemistry in the region undergoes a seasonal cycle, wherein the annual cycle of stratification-overturn, primary production, respiration-remineralization and mixing all play important roles, at distinct spatiotemporal scales. Surface production was tightly coupled with remineralization in the benthic nepheloid layer during high production seasons, which results in occasional aragonite undersaturation. From spring to summer, carbonate chemistry in the surface across Wilkinson Basin reflects a transition from a production-respiration balanced system to a net autotropic system. Mean water-column Ω-Ar and abundance of large thecosomatous pteropods show some correlation, although patchiness and discrete cohort reproductive success likely also influence their abundance. Overall, photosynthesis-respiration is the primary driving force controlling Ω-Ar variability during the spring-to-summer transition as well as over the seasonal cycle. However, calcium carbonate (CaCO3) dissolution appears to occur near bottom in fall and winter when bottom water Ω-Ar is generally low but slightly above 1. This is accompanied by a decrease in pteropod abundance that is consistent with previous CaCO3 flux trap measurements. The region might experience persistent subsurface aragonite undersaturation in 30–40 years under continued ocean acidification.Coastal Ocean Institute at Woods Hole Oceanographic Institution; National Science Foundation Grant Number: (OCE-1316040)2017-07-2

Cytotoxicity of Poly(Phenolic)Sulfonates and Their Sodium Salts in L1210 Lymphoid Leukemia Cells

Poly(phenolic)-sulfonates demonstrated very good cytotoxicity against the growth of tumor cell lines (L1210, Tmolt-3, HeLa-S3) and are comparable in potency with typical clinically used anticancer drugs. Four of the most active compounds, i.e. GL-2021, GL-2029, GL-2041 and GL-2063, were selected for a mode of action study in L1210 lymphoid leukemia cells at concentration of 25μM to 100μM for 60 min. The agents did not alkylate bases of ct-DNA, cause intercalation between base pairs, produce cross linking of ct-DNA strands or generate free radicals although L1210 DNA fragmentation was observed after 24 hr incubation. L1210 DNA synthesis was preferentially inhibited which was achieved by (1) suppressing DNA polymerase α activity which reduced the synthesis of new strands of DNA, (2) reducing of de novo purine synthesis at the regulatory enzyme PRPP amido transferase which reduced d(GMP) levels, and (3) inhibiting of nucleoside kinase activities which further reduced DNA synthesis. DNA template activity was altered by the poly(phenolic)sulfonates since they reduced DNA polymerase α and m-RNA and t-RNA polymerase activities. The kinetic studies at 50 μM over 2 hr demonstrated that the agents’ effect on PRPP-amido transferase activity is probably a major target of the compounds

Invasive Haemophilus influenzae Disease in Adults ≥65 Years, United States, 2011.

BackgroundSince the introduction of the Haemophilus influenzae serotype b vaccine, H influenzae epidemiology has shifted. In the United States, the largest burden of disease is now in adults aged ≥65 years. However, few data exist on risk factors for disease severity and outcome in this age group.MethodsA retrospective case-series review of invasive H influenzae infections in patients aged ≥65 years was conducted for hospitalized cases reported to Active Bacterial Core surveillance in 2011.ResultsThere were 299 hospitalized cases included in the analysis. The majority of cases were caused by nontypeable H influenzae, and the overall case fatality ratio (CFR) was 19.5%. Three or more underlying conditions were present in 63% of cases; 94% of cases had at least 1. Patients with chronic heart conditions (congestive heart failure, coronary artery disease, and/or atrial fibrillation) (odds ratio [OR], 3.27; 95% confidence interval [CI], 1.65-6.46), patients from private residences (OR, 8.75; 95% CI, 2.13-35.95), and patients who were not resuscitate status (OR, 2.72; 95% CI, 1.31-5.66) were more likely to be admitted to the intensive care unit (ICU). Intensive care unit admission (OR, 3.75; 95% CI, 1.71-8.22) and do not resuscitate status (OR, 12.94; 95% CI, 4.84-34.55) were significantly associated with death.ConclusionsWithin this age group, burden of disease and CFR both increased significantly as age increased. Using ICU admission as a proxy for disease severity, our findings suggest several conditions increased risk of disease severity and patients with severe disease were more likely to die. Further research is needed to determine the most effective approach to prevent H influenzae disease and mortality in older adults

IL-33 ameliorates Alzheimer’s disease-like pathology and cognitive decline

Alzheimer’s disease (AD) is a devastating condition with no known effective treatment. AD is characterized by memory loss as well as impaired locomotor ability, reasoning, and judgment. Emerging evidence suggests that the innate immune response plays a major role in the pathogenesis of AD. In AD, the accumulation of β-amyloid (Aβ) in the brain perturbs physiological functions of the brain, including synaptic and neuronal dysfunction, microglial activation, and neuronal loss. Serum levels of soluble ST2 (sST2), a decoy receptor for interleukin (IL)-33, increase in patients with mild cognitive impairment, suggesting that impaired IL-33/ST2 signaling may contribute to the pathogenesis of AD. Therefore, we investigated the potential therapeutic role of IL-33 in AD, using transgenic mouse models. Here we report that IL-33 administration reverses synaptic plasticity impairment and memory deficits in APP/PS1 mice. IL-33 administration reduces soluble Aβ levels and amyloid plaque deposition by promoting the recruitment and Aβ phagocytic activity of microglia; this is mediated by ST2/p38 signaling activation. Furthermore, IL-33 injection modulates the innate immune response by polarizing microglia/macrophages toward an antiinflammatory phenotype and reducing the expression of proinflammatory genes, including IL-1β, IL-6, and NLRP3, in the cortices of APP/PS1 mice. Collectively, our results demonstrate a potential therapeutic role for IL-33 in AD

Viscosity and Thermal Conductivity of Stable Graphite Suspensions Near Percolation

Nanofluids have received much attention in part due to the range of properties possible with different combinations of nanoparticles and base fluids. In this work, we measure the viscosity of suspensions of graphite particles in ethylene glycol as a function of the volume fraction, shear rate, and temperature below and above the percolation threshold. We also measure and contrast the trends observed in the viscosity with increasing volume fraction to the thermal conductivity behavior of the same suspensions: above the percolation threshold, the slope that describes the rate of thermal conductivity enhancement with concentration reduces compared to below the percolation threshold, whereas that of the viscosity enhancement increases. While the thermal conductivity enhancement is independent of temperature, the viscosity changes show a strong dependence on temperature and exhibit different trends with respect to the temperature at different shear rates above the percolation threshold. Interpretation of the experimental observations is provided within the framework of Stokesian dynamics simulations of the suspension microstructure and suggests that although diffusive contributions are not important for the observed thermal conductivity enhancement, they are important for understanding the variations in the viscosity with changes of temperature and shear rate above the percolation threshold. The experimental results can be collapsed to a single master curve through calculation of a single dimensionless parameter (a Péclet number based on the rotary diffusivity of the graphite particles).United States. Air Force Office of Scientific Research (FA9550-11-1-0174)National Natural Science Foundation (China) (51036003

NMDA Receptors Subserve Persistent Neuronal Firing during Working Memory in Dorsolateral Prefrontal Cortex

SummaryNeurons in the primate dorsolateral prefrontal cortex (dlPFC) generate persistent firing in the absence of sensory stimulation, the foundation of mental representation. Persistent firing arises from recurrent excitation within a network of pyramidal Delay cells. Here, we examined glutamate receptor influences underlying persistent firing in primate dlPFC during a spatial working memory task. Computational models predicted dependence on NMDA receptor (NMDAR) NR2B stimulation, and Delay cell persistent firing was abolished by local NR2B NMDAR blockade or by systemic ketamine administration. AMPA receptors (AMPARs) contributed background depolarization to sustain network firing. In contrast, many Response cells were sensitive to AMPAR blockade and increased firing after systemic ketamine, indicating that models of ketamine actions should be refined to reflect neuronal heterogeneity. The reliance of Delay cells on NMDAR may explain why insults to NMDARs in schizophrenia or Alzheimer’s disease profoundly impair cognition

Targeting fibroblast activation protein in tumor stroma with chimeric antigen receptor T cells can inhibit tumor growth and augment host immunity without severe toxicity.

The majority of chimeric antigen receptor (CAR) T-cell research has focused on attacking cancer cells. Here, we show that targeting the tumor-promoting, nontransformed stromal cells using CAR T cells may offer several advantages. We developed a retroviral CAR construct specific for the mouse fibroblast activation protein (FAP), comprising a single-chain Fv FAP [monoclonal antibody (mAb) 73.3] with the CD8α hinge and transmembrane regions, and the human CD3ζ and 4-1BB activation domains. The transduced muFAP-CAR mouse T cells secreted IFN-γ and killed FAP-expressing 3T3 target cells specifically. Adoptively transferred 73.3-FAP-CAR mouse T cells selectively reduced FAP(hi) stromal cells and inhibited the growth of multiple types of subcutaneously transplanted tumors in wild-type, but not FAP-null immune-competent syngeneic mice. The antitumor effects could be augmented by multiple injections of the CAR T cells, by using CAR T cells with a deficiency in diacylglycerol kinase, or by combination with a vaccine. A major mechanism of action of the muFAP-CAR T cells was the augmentation of the endogenous CD8(+) T-cell antitumor responses. Off-tumor toxicity in our models was minimal following muFAP-CAR T-cell therapy. In summary, inhibiting tumor growth by targeting tumor stroma with adoptively transferred CAR T cells directed to FAP can be safe and effective, suggesting that further clinical development of anti-human FAP-CAR is warranted

Student Perceptions and Engagement in Video-based Learning for Microbiology Education

Online learning increases the physical distance between instructors and students and depending on the mode of delivery, it can be challenging to close this gap. To ameliorate this potential for student isolation, instructors need to communicate to students in a variety of ways, blending original online resources with synchronous interactive learning activities. During 2020, 34 lecture videos were created for a large undergraduate microbiology and immunology course offered at The University of Queensland. The teaching team applied a subset of Mayer’s multimedia learning design principles – embodiment, mixed perspectives, segmenting, signalling – to create videos featuring instructor presence, multiple presentation styles, and dynamic pacing. When compared to voice-over presentations created by automated lecture capture software, the outcomes of this design process increased student engagement in video-based learning across the 2020 and 2021 course offerings. Analysis of student perception data collected by online questionnaires and interviews revealed broad agreement with the design principles used for video-based learning. However, their value of on-screen instructor visibility, graphics, and text was variable as a result of individual preferences. Together these findings present a case study in which instructional videos were developed iteratively through the selective application of multimedia design principles and strategic adaptation of existing learning resources