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The objective of this study was to create a North American e-cigarette, or electronic nicotine delivery system (ENDS), market map representative of the 2020 and 2021 commercial market for analysis of harmful and potentially harmful constituents (HPHCs) and other chemicals in aerosol. The study consisted of 14 brands (seven closed pod-based, four open (refillable) pod-based, two cigalike, one disposable) and analyzed multiple e-liquid formulations per brand with varying labelled nicotine concentrations and flavors, equating to 35 unique tested ENDS. Aerosol was generated using two puffing regimes (ISO 27068 and intense) and analyzed for primary constituents, metals, carbonyls, and glycidol in a head-to-head comparison in the same testing laboratory. Nicotine yields per puff ranged from 0.045 mg/puff for the lowest yielding ENDS under the ISO 27068 puffing regime to 1.11 mg/puff for the highest yielding ENDS under intense puffing conditions. For carbonyls, all ENDS generated quantifiable amounts of acetaldehyde, acrolein, and formaldehyde in collected aerosol, irrespective of puffing regime, with an increase in yields observed under intense puffing compared to ISO 27068 puffing for the majority of tested ENDS. For metals, the ENDS aerosol yielded nickel (Ni) ranging from below limits of detection (BLOD) to >30 ng/puff, while quantifiable levels of chromium (Cr), copper (Cu), and lead (Pb) were only associated with select ENDS. All tested ENDS aerosol contained quantifiable glycidol ranging from 0.003 to >1.00 µg/puff for ISO 20768 and 0.005 to 1.10 µg/puff for intense puffing regimes. As a category, ENDS aerosol showed significantly reduced levels of HPHCs compared to 1R6F combustible cigarette (CC) smoke on a per nicotine basis. However, there was variability among ENDS and the aerosol of some ENDS products produced increased levels of specific HPHCs (e.g., formaldehyde and nickel) compared to 1R6F CC smoke. The observed HPHC variations appear to be primarily dependent on device design. In summary, this work is one of the most comprehensive analyses of HPHCs for North American ENDS using validated analytical methods in the same test facility for a head-to-head comparison.

In 2020, the coronavirus (COVID-19) pandemic forced teachers in Ontario to move online. Since then, teaching online or in hybrid models has been common across the province. To understand how French as a Second Language (FSL) teachers navigated these spaces, four Ontario French teachers were interviewed about their experience using educational technology and teaching online. Findings were analyzed in light of Hargreaves and Fullan's (2020) reframing of classic understandings of teachers' work in the context of the global pandemic. Findings show that factors influencing these teachers' professional capital reflect common concerns among Canadian educators, alongside those specific to the FSL context. Participants' professional marginalization and seclusion demonstrates the importance of both the psychic rewards of teaching and cultures of collaboration. Ongoing efforts to capture ways in which teaching FSL has been shaped by the pandemic experience, therefore, require looking beyond individual classrooms to connected systems and systematic efforts of reform.

BackgroundPostamputation phantom pain is notoriously persistent with few validated treatments. Cryoneurolysis involves the application of low temperatures to reversibly ablate peripheral nerves. The authors tested the hypothesis that a single cryoneurolysis treatment would decrease phantom pain 4 months later.MethodsThe authors enrolled patients with a lower-limb amputation and established phantom pain. Each received a single-injection femoral and sciatic nerve block with lidocaine and was subsequently randomized to receive either ultrasound-guided percutaneous cryoneurolysis or sham treatment at these same locations. The primary outcome was the change in average phantom pain intensity between baseline and 4 months as measured with a numeric rating scale (0 to 10), after which an optional crossover treatment was offered. Investigators, participants, and clinical staff were masked to treatment group assignment with the exception of the treating physician performing the cryoneurolysis, who had no subsequent participant interaction.ResultsPretreatment phantom pain scores were similar in both groups, with a median [quartiles] of 5.0 [4.0, 6.0] for active treatment and 5.0 [4.0, 7.0] for sham. After 4 months, pain intensity decreased by 0.5 [-0.5, 3.0] in patients given cryoneurolysis (n = 71) versus 0 [0, 3] in patients given sham (n = 73), with an estimated difference (95% CI) of -0.1 (-1.0 to 0.7), P = 0.759. Following their statistical gatekeeping protocol, the authors did not make inferences or draw conclusions on secondary endpoints. One serious adverse event occurred after a protocol deviation in which a femoral nerve cryolesion was induced just below the inguinal ligament-instead of the sensory-only saphenous nerve-which resulted in quadriceps weakness, and possibly a fall and clavicle fracture.ConclusionsPercutaneous cryoneurolysis did not decrease chronic lower extremity phantom limb pain 4 months after treatment. However, these results were based upon the authors' specific study protocol, and since the optimal cryoneurolysis treatment parameters such as freeze duration and anatomic treatment location remain unknown, further research is warranted.Editor’s perspective

Institutions strive to offer programs that address both the needs of the educational system and incorporate current pedagogical research. Creating a program that is relevant, inspiring, and accessible to aspiring French as a Second Language (FSL) teachers, while also equipping them with the skills and knowledge deemed necessary by the education system, is a delicate balancing act. This study reviewed 44 FSL teacher education programs that lead to professional certification across Canada. Environmental scans drew information from the program websites related to admission requirements, program structure and content, practicum, and graduation criteria. Follow-up interviews with program stakeholders were conducted to verify or clarify the data. The results highlight the inconsistencies that exist among programs for developing FSL educators. We position the ways in which Canadian faculties of education might provide a more holistic "pathway" approach to recruiting, preparing, and retaining emerging FSL teachers.

As both educational technology and Communities of Practice (CoPs) have become more established in schools globally, it is unsurprising that they have been employed together to improve teachers' practice. The creation of collaborative professional learning groups to support the use of educational technology in the classroom has been explored in research literature, yet questions remain about the impact and effectiveness that such interventions have for participating teachers. This qualitative meta-synthesis explores how CoPs are used to facilitate teacher professional learning regarding classroom technology integration, and the reported outcomes on teacher practice and student learning. While the studies are consistently positive in their analysis of CoPs, we contend that the current literature is limited in being largely focused on reporting change over impact. Our analysis highlights limitations and inconsistencies in the extant studies, provides suggestions for researchers and practitioners aiming to implement CoPs focused on educational technology, as well as directions for future research around these topics.

Axon initial segments (AISs) generate action potentials and regulate the polarized distribution of proteins, lipids, and organelles in neurons. While the mechanisms of AIS Na+ and K+ channel clustering are understood, the molecular mechanisms that stabilize the AIS and control neuronal polarity remain obscure. Here, we use proximity biotinylation and mass spectrometry to identify the AIS proteome. We target the biotin-ligase BirA* to the AIS by generating fusion proteins of BirA* with NF186, Ndel1, and Trim46; these chimeras map the molecular organization of AIS intracellular membrane, cytosolic, and microtubule compartments. Our experiments reveal a diverse set of biotinylated proteins not previously reported at the AIS. We show many are located at the AIS, interact with known AIS proteins, and their loss disrupts AIS structure and function. Our results provide conceptual insights and a resource for AIS molecular organization, the mechanisms of AIS stability, and polarized trafficking in neurons.

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.

This music score was submitted for the Kaleidoscope 2020 Call for Scores, an open access collaboration with the UCLA Music Library.

We found a startling correlation (Pearson ρ > 0.97) between a single event in daily sea surface temperatures each spring, and peak fish egg abundance measurements the following summer, in 7 years of approximately weekly fish egg abundance data collected at Scripps Pier in La Jolla California. Even more surprising was that this event-based result persisted despite the large and variable number of fish species involved (up to 46), and the large and variable time interval between trigger and response (up to ~3 months). To mitigate potential over-fitting, we made an out-of-sample prediction beyond the publication process for the peak summer egg abundance observed at Scripps Pier in 2020 (available on bioRxiv). During peer-review, the prediction failed, and while it would be tempting to explain this away as a result of the record-breaking toxic algal bloom that occurred during the spring (9x higher concentration of dinoflagellates than ever previously recorded), a re-examination of our methodology revealed a potential source of over-fitting that had not been evaluated for robustness. This cautionary tale highlights the importance of testable true out-of-sample predictions of future values that cannot (even accidentally) be used in model fitting, and that can therefore catch model assumptions that may otherwise escape notice. We believe that this example can benefit the current push towards ecology as a predictive science and support the notion that predictions should live and die in the public domain, along with the models that made them.

Gold nanoparticles (AuNPs) are commonly used in cancer research due to their unique physical and optical properties. However, current AuNP synthesis methods often involve cytotoxic cationic surfactants such as cetyltrimethylammonium bromide (CTAB). Tedious CTAB replacement methodologies have been used to increase the biocompatibility, further increasing the complexity of synthesizing biocompatible AuNPs and limiting their biomedical applications. To address this issue, we explore cholinium decanoate (CADA) ionic liquid (IL) as a biocompatible stabilizing agent by replacing CTAB using a simple modified seeded method for synthesizing anisotropic AuNPs for photothermal therapy of triple-negative breast cancer cells (MDA-MB-231). The prepared CADA AuNPs showed a quasi-spherical morphology, confirmed by transmission electron microscopy (TEM) and a broad plasmonic absorption band using vis-NIR spectroscopy. CADA AuNPs exhibited excellent in vitro biocompatibility with both MCF-10A (healthy human mammary cells) and MDA-MB-231 cells. We evaluate their in vitro photothermal efficacy against MDA-MB-231 cancer cells, demonstrating significant cell death even at low AuNP concentration (20 μg/mL), low laser power density (0.6 W/cm2, 808 nm continuous laser), and short irradiation time of 5 min, primarily through apoptosis. Overall, this work represents the first effort in using a modified seeded method for synthesizing biocompatible IL-based anisotropic AuNPs for photothermal therapy, offering a promising avenue for future cancer treatment research using ILs. [ABSTRACT FROM AUTHOR]

Third space professional staff have been emerging as leaders and key contributors to higher education institutions around the world. These staff are employed to support initiatives in such areas as teaching and learning, research management, student services, community engagement, and strategic initiatives, some of which were previously the sole domains of academics. Positioned between these academic and professional spheres, four professionals from the University of Calgary engaged in narrative inquiry to reflect on how their context and lived experiences inform their identities navigating the third space. The authors describe how role ambiguity, self-advocacy, positional liminality, and cross-boundary relationships create challenges and opportunities for third space professionals as they navigate the institution and define their place in it. Implications and suggestions for higher education administrative leaders are provided, based on opportunities for third space professional staff to effectively operate within their organisations.

The Extended Evolutionary Synthesis (EES) is beginning to fulfill the whole promise of Darwinian insight through its extension of evolutionary understanding from the biological domain to include cultural information evolution. This constitutes the origins of an evolutionary study of culture change free of the social-darwinism and ecologically-deterministic baggage that characterized earlier such approaches.

Unbalanced voltages are becoming increasingly common in distribution networks due to the growing integrations of distributed renewable energy resources as well as large loads such as electric vehicle chargers. Such unbalanced voltages introduce significant control challenges as they produce ripples in the controlling signals, impacting the operation of inverters during the unbalanced conditions. Therefore, this paper proposes a controlling algorithm for three‐level inverters aimed at suppressing these ripples on controlling signals; improving the overall performance of inverters, and consequently enhancing the fault ride‐through capability under unbalanced conditions and faults. The proposed controlling algorithm enables inverters to operate in either a balanced current output mode or a suppressed‐ripple active power output mode, depending on the specific event scenario and demands from the grid operators. Current harmonics are suppressed even under severe faults. For improving the voltage balance on the DC capacitors in three‐level inverters, an enhanced method of neutral point current prediction is presented. The proposed method ensures higher balancing accuracy through the use of weighted switching costs, avoiding the requirement of a balancing controller or current extrapolation. Simulation and experimental results demonstrate the effectiveness of the proposed controller for reliable grid operation. [ABSTRACT FROM AUTHOR]

Both the biological effects and acoustic emissions generated by cavitation are functions of bubble dynamics. Monitoring of acoustic emissions is therefore desirable to improve treatment safety and efficacy. The relationship between the emission spectra and bubble dynamics is, however, complex. The aim of this study was to characterise this relationship for single microbubbles using simultaneous ultra-high-speed optical imaging and passive acoustic mapping of cavitation emissions. As expected, both the number of discrete harmonics and broadband content in the emissions increased with increasing amplitude of bubble oscillation, but the spectral content was also dependent upon other variables, including the frequency of bubble collapse and receiving transducer characteristics. Moreover, phenomena, such as fragmentation and microjetting, could not be distinguished from spherical oscillations when using the full duration acoustic waveform to calculate the emission spectra. There was also no correlation between the detection of broadband noise and widely used thresholds for distinguishing bubble dynamics. It is therefore concluded that binary categorisations, such as stable and inertial cavitation, should be avoided, and different types of bubble behavior should not be inferred on the basis of frequency content alone. Treatment monitoring criteria should instead be defined according to the relevant bioeffect(s) for a particular application. [ABSTRACT FROM AUTHOR]

Recording and analysis of neural activity are often biased toward detecting sparse subsets of highly active neurons, masking important signals carried in low-magnitude and variable responses. To investigate the contribution of seemingly noisy activity to odor encoding, we used mesoscale calcium imaging from mice of both sexes to record odor responses from the dorsal surface of bilateral olfactory bulbs (OBs). The outer layer of the mouse OB is comprised of dendrites organized into discrete "glomeruli," which are defined by odor receptor-specific sensory neuron input. We extracted activity from a large population of glomeruli and used logistic regression to classify odors from individual trials with high accuracy. We then used add-in and dropout analyses to determine subsets of glomeruli necessary and sufficient for odor classification. Classifiers successfully predicted odor identity even after excluding sparse, highly active glomeruli, indicating that odor information is redundantly represented across a large population of glomeruli. Additionally, we found that random forest (RF) feature selection informed by Gini inequality (RF Gini impurity, RFGI) reliably ranked glomeruli by their contribution to overall odor classification. RFGI provided a measure of "feature importance" for each glomerulus that correlated with intuitive features like response magnitude. Finally, in agreement with previous work, we found that odor information persists in glomerular activity after the odor offset. Together, our findings support a model of OB odor coding where sparse activity is sufficient for odor identification, but information is widely, redundantly available across a large population of glomeruli, with each glomerulus representing information about more than one odor [ABSTRACT FROM AUTHOR]

Why do languages parcel human experience into categories inthe ways they do? Languages vary widely in their categorysystems but not arbitrarily, and one possibility is that thisconstrained variation reflects universal communicative needs.Consistent with this idea, it has been shown that attestedcategory systems tend to support highly informativecommunication. However it is not yet known what processproduces these informative systems. Here we show thathuman simulation of cultural transmission in the lab producessystems of semantic categories that converge toward greaterinformativeness, in the domains of color and spatial relations.These findings suggest that larger-scale cultural transmissionover historical time could have produced the diverse yetinformative category systems found in the world’s languages.

Small organic molecules absorbing and emitting in the shortwave infrared (SWIR, 1000–2000 nm) region are desirable for biological imaging applications due to low auto‐fluorescence, reduce photon scattering, and good tissue penetration depth of photons which allows for in vivo imaging with high resolution and sensitivity. Si‐substituted xanthene‐based fluorophores with indolizine donors have demonstrated some of the longest wavelengths of absorption and emission from organic dyes. This work seeks to compare an indolizine heterocyclic nitrogen with dimethyl aniline nitrogen donors on otherwise identical Si‐substituted xanthene fluorophores via optical spectroscopy, computational chemistry and electrochemistry. Three donors are compared including an indolizine donor, a ubiquitous dimethyl aniline donor, and a vinyl dimethyl aniline group that keeps the number of π‐bonds consistent with indolizine. Significantly higher quantum yields and molar absorptivity are observed in these studies for a dimethylamine‐based donor relative to a simple indolizine donor absorbing and emitting at similar wavelengths (~1312 nm emission). Substantially longer wavelengths are obtainable by appending aniline‐based groups to the indolizine donor (~1700 nm) indicating longer wavelengths can be accessed with indolizine donors while stronger emitters can be accessed with anilines in place of indolizine. [ABSTRACT FROM AUTHOR]