Showing papers by "Matthew Jones published in 2022"
TL;DR: In this article , nine new complexes based on thioether appended iminophenolate (ONS) ligands have been prepared and fully characterized in solution by NMR spectroscopy.
Abstract: Nine new complexes based on thioether appended iminophenolate (ONS) ligands have been prepared and fully characterized in solution by NMR spectroscopy. Solid-state structures were also obtained for seven complexes. In solution, all complexes were monomeric. The complexes were highly active for the polymerization of purified rac-lactide ([M] : [Zn] : [BnOH] = 10 000 : 1 : 30 at 180 °C) reaching TOF values up to 250 000 h−1. The kinetics of the polymerization have been probed by in situ Raman spectroscopy. The rate of reaction was dramatically reduced using technical grade rac-lactide with increased initiator loading. To move towards a circular economy, it is vital that catalysts are developed to facilitate chemical recycling of commodity and emerging polymeric materials. In this vein, the complexes have been assessed for their ability to break down poly(lactic acid) and poly(ethylene terephthalate). The results from both the polymerization and degradation reactions are discussed in terms of ligand functionality.
10 citations
TL;DR: In this article , the first example of discrete metal-mediated poly(bisphenol A carbonate) (BPA•PC) methanolysis being appreciably active at room temperature was reported.
Abstract: Abstract ZnII‐complexes bearing half‐salan ligands were exploited in the mild and selective chemical upcycling of various commercial polyesters and polycarbonates. Remarkably, we report the first example of discrete metal‐mediated poly(bisphenol A carbonate) (BPA‐PC) methanolysis being appreciably active at room temperature. Indeed, Zn(2)2 and Zn(2)Et achieved complete BPA‐PC consumption within 12–18 mins in 2‐Me‐THF, noting high bisphenol A (BPA) yields (SBPA =85–91 %) within 2–4 h. Further kinetic analysis found such catalysts to possess kapp values of 0.28±0.040 and 0.47±0.049 min−1 respectively at 4 wt%, the highest reported to date. A completely circular upcycling approach to plastic waste was demonstrated through the production of several renewable poly(ester‐amide)s (PEAs), based on a terephthalamide monomer derived from bottle‐grade poly(ethylene terephthalate) (PET), which exhibited excellent thermal properties.
9 citations
TL;DR: In this paper , carbonate clumped isotope (Δ47) paleotemperatures of the mid-Cretaceous thermal maximum were measured from Cenomanian oyster fossils of the Western Interior Seaway.
Abstract: The mid-Cretaceous thermal maximum (KTM) during Cenomanian to Santonian times from ca. 100 to 83 Ma is considered among Earth’s warmest sustained intervals of the Phanerozoic. The time interval is also characterized by major paleoceanographic changes in the form of an oceanic anoxic event and the flooding of epicontinental seaways, such as the Western Interior Seaway in North America. We report carbonate clumped isotope (Δ47) paleotemperatures (TΔ47) of the KTM measured from Cenomanian oyster fossils of the Western Interior Seaway. Following screening of specimens for carbonate diagenesis and exclusion of geographic zones with evidence consistent with solid-state Δ47 reordering, a mean TΔ47 of 28–34 °C (95% confidence interval for the standard error of mean) for primary oyster calcite quantifies extreme mid-latitude warmth in North America. When combined with existing Campanian and Maastrichtian marine TΔ47 records, the new data constrain Late Cretaceous temperature trends underlying the evolution of North American faunal and stratigraphic records. These TΔ47 data from the peak KTM highlight the potential of this proxy to quantitatively resolve the upper thermal limits of Phanerozoic greenhouse climates.
8 citations
TL;DR: The authors describe the rationale and design for a model for discipline-based faculty development to support instructional change, and detail their implementation of this model as applied to intensive workshops on inquiry-based learning (IBL) in college mathematics.
Abstract: ABSTRACT Faculty professional development is an important lever for change in supporting instructors to adopt research-based instructional strategies that engage students intellectually, foster learning-supportive attitudes and habits of mind, and strengthen their persistence in mathematics. Yet the literature contains few well-rationalized models for faculty development in higher education. We describe the rationale and design for a model for discipline-based faculty development to support instructional change, and we detail our implementation of this model as applied to intensive workshops on inquiry-based learning (IBL) in college mathematics. These workshops seek to foster post-secondary mathematics instructors’ adoption of IBL, to help them adapt inquiry approaches for their classrooms, and ultimately to increase student learning and persistence in science and mathematics. Based on observed faculty needs, four strands of activity help instructors develop a mental model for an IBL classroom, adapt that model to their teaching context, develop facilitation and task-design skills, and plan an IBL mathematics course. Evaluation data from surveys and observations illustrate participant responses to the workshop and its components. The model has been robust across 15 years of workshops implemented by three generations of workshop leaders and its features make it adaptive, strategic, and practical for other faculty developers.
4 citations
TL;DR: The ring-opening co-polymerization (ROCOP) of epoxides and cyclic anhydrides is a versatile route to new polyesters as discussed by the authors , and the vast number of monomers that are readily available means that an effectively limitless...
4 citations
TL;DR: In this paper , isolated integrin receptor complexes from human pancreatic ductal epithelial (HPDE) cells predominantly identified integrin α6β4 and hemidesmosome components, rather than classical focal adhesion components.
4 citations
29 Apr 2022
TL;DR: In this paper , the authors investigate how to integrate touchless technologies into public-space infrastructure in order to minimise physical interaction with shared devices in light of the ongoing COVID-19 pandemic.
Abstract: What do pedestrian crossings, ATMs, elevators and ticket machines have in common? These are just a few of the ubiquitous yet essential elements of public-space infrastructure that rely on physical buttons or touchscreens; common interactions that, until recently, were considered perfectly safe to perform. This work investigates how we might integrate touchless technologies into public-space infrastructure in order to minimise physical interaction with shared devices in light of the ongoing COVID-19 pandemic. Drawing on an ethnographic exploration into how public utilities are being used, adapted or avoided, we developed and evaluated a suite of technology probes that can be either retrofitted into, or replace, these services. In-situ community deployments of our probes demonstrate strong uptake and provide insight into how hands-free technologies can be adapted and utilised for the public domain; and, in turn, used to inform the future of walk-up-and use public technologies.
3 citations
TL;DR: Smoking-induced epigenetic DNA hypomethylation at F2RL3 appears to increase PAR4 expression with potential downstream consequences for platelet reactivity, and results from reporter assays suggest the exon 2 region of F2 RL3 may help control gene expression.
Abstract: Supplemental Digital Content is available in the text. Background: DNA hypomethylation at the F2RL3 (F2R like thrombin or trypsin receptor 3) locus has been associated with both smoking and atherosclerotic cardiovascular disease; whether these smoking-related associations form a pathway to disease is unknown. F2RL3 encodes protease-activated receptor 4, a potent thrombin receptor expressed on platelets. Given the role of thrombin in platelet activation and the role of thrombus formation in myocardial infarction, alterations to this biological pathway could be important for ischemic cardiovascular disease. Methods: We conducted multiple independent experiments to assess whether DNA hypomethylation at F2RL3 in response to smoking is associated with risk of myocardial infarction via changes to platelet reactivity. Using cohort data (N=3205), we explored the relationship between smoking, DNA hypomethylation at F2RL3, and myocardial infarction. We compared platelet reactivity in individuals with low versus high DNA methylation at F2RL3 (N=41). We used an in vitro model to explore the biological response of F2RL3 to cigarette smoke extract. Finally, a series of reporter constructs were used to investigate how differential methylation could impact F2RL3 gene expression. Results: Observationally, DNA methylation at F2RL3 mediated an estimated 34% of the smoking effect on increased risk of myocardial infarction. An association between methylation group (low/high) and platelet reactivity was observed in response to PAR4 (protease-activated receptor 4) stimulation. In cells, cigarette smoke extract exposure was associated with a 4.9% to 9.3% reduction in DNA methylation at F2RL3 and a corresponding 1.7-(95% CI, 1.2–2.4, P=0.04) fold increase in F2RL3 mRNA. Results from reporter assays suggest the exon 2 region of F2RL3 may help control gene expression. Conclusions: Smoking-induced epigenetic DNA hypomethylation at F2RL3 appears to increase PAR4 expression with potential downstream consequences for platelet reactivity. Combined evidence here not only identifies F2RL3 DNA methylation as a possible contributory pathway from smoking to cardiovascular disease risk but from any feature potentially influencing F2RL3 regulation in a similar manner.
3 citations
29 Apr 2022
TL;DR: This work implemented a VA that handles requests in three response styles: two differing short keyword-based response styles and a full-sentence baseline, and argues that VAs should be customizable and adapt to users instead of always responding in full sentences.
Abstract: Voice assistants (VAs) are present in homes, smartphones, and cars. They allow users to perform tasks without graphical or tactile user interfaces, as they are designed for natural language interaction. However, we found that currently, VAs are emulating human behavior by responding in complete sentences, limiting the design options, and preventing VAs from meeting their full potential as a utilitarian tool. We implemented a VA that handles requests in three response styles: two differing short keyword-based response styles and a full-sentence baseline. In a user study, 72 participants interacted with our VA by issuing eight requests. Results show that the short responses were perceived similarly useful and likable while being perceived as more efficient, especially for commands, and sometimes better to comprehend than the baseline. To achieve widespread adoption, we argue that VAs should be customizable and adapt to users instead of always responding in full sentences.
3 citations
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TL;DR: This work proposes a variant of fairness which restricts each group’s number of centers with both a lower bound (minority-protection) and an upper bound (restricted-domination) and provides both an offline and one-pass streaming algorithm for the problem.
Abstract: We study the problem of fairness in k-centers clustering on data with disjoint demographic groups. Specifically, this work proposes a variant of fairness which restricts each group's number of centers with both a lower bound (minority-protection) and an upper bound (restricted-domination), and provides both an offline and one-pass streaming algorithm for the problem. In the special case where the lower bound and the upper bound is the same, our offline algorithm preserves the same time complexity and approximation factor with the previous state-of-the-art. Furthermore, our one-pass streaming algorithm improves on approximation factor, running time and space complexity in this special case compared to previous works. Specifically, the approximation factor of our algorithm is 13 compared to the previous 17-approximation algorithm, and the previous algorithms' time complexities have dependence on the metric space's aspect ratio, which can be arbitrarily large, whereas our algorithm's running time does not depend on the aspect ratio.
2 citations
TL;DR: In this paper , the evidence of a new potential target for treating diabetic peripheral neuropathy, the ligands for nicotinic acetylcholine receptors (nAChRs), specifically α4ꞵ2 agonists and α9α10 antagonists, was explored.
27 Apr 2022
TL;DR: This special interest group (SIG) follows up on previous conversations around hybrid models for conferences, conducted in open sessions by the ACM Special Interest Group on Computer-Human Interaction (SigCHI) Executive Committee (EC).
Abstract: In this special interest group (SIG), we follow up on previous conversations around hybrid models for conferences, conducted in open sessions by the ACM Special Interest Group on Computer-Human Interaction (SIGCHI) Executive Committee (EC). The COVID-19 pandemic led to a sudden shift to virtual conferences; as we start to go back to in-person events, it is important to reflect on the types of events we desire, and design these accordingly. With this SIG, we hope to share experiences from previous conferences (successful or not) and discuss potential solutions to pending issues. This SIG will be led by VP at Large Adriana S. Vivacqua, with the participation of other EC members.
TL;DR: In this article , an aerobic oxidation operated in continuous flow is described as the key step in an efficient three-step route to AZD4635, where the Fourier transform infrared (FTIR) was employed to obtain a real-time analysis during the optimization in flow.
TL;DR: In this article , an extended depth-of-field selective-plane illumination microscopy (ExD-SPIM) was proposed to match the thickness of the illumination light sheet.
Abstract: Light-sheet microscopes must compromise among field of view, optical sectioning, resolution, and detection efficiency. High-numerical-aperture (NA) detection objective lenses provide higher resolution, but their narrow depth of field inefficiently captures the fluorescence signal generated throughout the thickness of the illumination light sheet when imaging large volumes. Here, we present ExD-SPIM (extended depth-of-field selective-plane illumination microscopy), an improved light-sheet microscopy strategy that solves this limitation by extending the depth of field (DOF) of high-NA detection objectives to match the thickness of the illumination light sheet. This extension of the DOF uses a phase mask to axially stretch the point-spread function of the objective lens while largely preserving lateral resolution. This matching of the detection DOF to the illumination-sheet thickness increases the total fluorescence collection, reduces the background, and improves the overall signal-to-noise ratio (SNR), as shown by numerical simulations, imaging of bead phantoms, and imaging living animals. In comparison to conventional light sheet imaging with low-NA detection that yields equivalent DOF, the results show that ExD-SPIM increases the SNR by more than threefold and dramatically reduces the rate of photobleaching. Compared to conventional high-NA detection, ExD-SPIM improves the signal sensitivity and volumetric coverage of whole-brain activity imaging, increasing the number of detected neurons by over a third.
TL;DR: In this article , the authors focus on the repercussions of remarks made by Duncan Sandys, the British Minister of Defence, at a press conference held in Canberra in August 1957 which suggested that British nuclear weapons were going to be deployed to airbases in Malaya.
Abstract: ABSTRACT This article focuses on the repercussions of remarks made by Duncan Sandys, the British Minister of Defence, at a press conference held in Canberra in August 1957 which suggested that British nuclear weapons were going to be deployed to airbases in Malaya. Against the background of the negotiations that had led to the Anglo-Malayan defence agreement, and with Malaya on the cusp of independence, an intense debate took place between Whitehall officials over whether and what form of assurances over consultation should be given to Malaya’s new leaders over the deployment of nuclear weapons and the use of Malayan bases. Besides examining why and how such assurances were issued, this article seeks to demonstrate the tensions produced by British defence policy in South East Asia during this period, which was increasingly rooted in alliance obligations to SEATO and the consequent projection of nuclear capabilities, as they began to conflict with the political imperative to bolster the post-independence United Malays National Organisation (UMNO) Alliance government in Malaya. It also brings forward some of the links and connections that can be made between nuclear issues and the dynamics of decolonisation.
23 Sep 2022
TL;DR: A new efficient algorithm with lower regret than even previous inefflcient ones, inspired by a long line of work in social choice and economics to optimize the Nash social welfare instead of the total utility is proposed.
Abstract: Recently a multi-agent variant of the classical multi-armed bandit was proposed to tackle fairness issues in online learning. Inspired by a long line of work in social choice and economics, the goal is to optimize the Nash social welfare instead of the total utility. Unfortunately previous algorithms either are not efficient or achieve sub-optimal regret in terms of the number of rounds. We propose a new efficient algorithm with lower regret than even previous inefficient ones. We also complement our efficient algorithm with an inefficient approach with regret that matches the lower bound for one agent. The experimental findings confirm the effectiveness of our efficient algorithm compared to the previous approaches.
27 Apr 2022
TL;DR: This case study documents the development and evaluation of a COVID-safe touchable device from early 2020 when people were told to avoid actions that might spread the virus, with lessons for future pandemic scenarios.
Abstract: Due to public concerns over touch-based disease transmission, tangible and embedded interfaces are perhaps the most unsuited technology during a pandemic. Even so, this case study documents the development and evaluation of such a system from early 2020 when people were told to avoid actions that might spread the virus (e.g., touch). Adding to the challenge, the Lookout was installed outside in a city centre for widespread public use. Despite these challenges, a COVID-safe touchable device was embedded and extensively used. This Case Study reports the co-creation of the device noting COVID restriction adaptations over a nine-month deployment. Our contributions are twofold: the study acts as a case-point of the impact of the unique COVID design context, with lessons for future pandemic scenarios; and, given we had over 10,000 users at a time when people were cautious about using shared devices or services, we surface some design characteristics that can promote the use of public technology.
07 Mar 2022