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Family of levoglucosan-derived renewable networks via UV-initiated thiol–ene click chemistry with tailorable properties for 3D printing of hydrolytically degradable parts.

Polymer blend compatibilization is an attractive solution for mechanical recycling of mixed plastic waste because it can result in tough blends. In this work, hydroxy-telechelic polyethylene (HOPEOH) reactive additives were used to compatibilize blends of polyethylene terephthalate (PET) and linear low-density polyethylene (LLDPE). HOPEOH additives were synthesized with molar masses of 1-20 kg/mol by ring-opening metathesis polymerization of cyclooctene followed by catalytic hydrogenation. Melt-compounded blends containing 0.5 wt % HOPEOH displayed reduced dispersed phase LLDPE particle sizes with ductilities comparable to virgin PET and almost seven times greater than neat blends, regardless of additive molar mass. In contrast, analogous blends containing monohydroxy PE additives of comparable molar masses did not result in compatibilization even at 2 wt % loading. The results strongly suggest that both hydroxy ends of HOPEOH undergo transesterification reactions during melt mixing with PET to form predominantly PET-PE-PET triblock copolymers at the interface of the dispersed and matrix phases. We hypothesize that the triblock copolymer compatibilizers localized at the interface form trapped entanglements of the PE midblocks with nearby LLDPE homopolymer chains by a hook-and-clasp mechanism. Finally, HOPEOH compounds were able to efficiently compatibilize blends derived solely from postconsumer PET and PE bottles and film, suggesting their industrial applicability.

The COVID-19 pandemic was one of the most devastating disasters of the twenty-first century and has exacted a steep health and economic toll. During times of suffering caused by the pandemic, religion/spirituality may prove to be a consistent and valuable coping resource.We situate changes in religious importance and reliance on God as key aspects of religious life that may be important coping mechanisms in response to pandemic-related financial hardship, addressing a gap in the literature on religious coping during the pandemic and considering self-reported changes in religiosity.We use data from a nationally representative sample of Americans that was collected in 2021 (N = 1704) and employ a series of OLS Regression Models.Our results suggest that relying more heavily on God was associated with lower psychological distress, and a stronger reliance on God buffered the deleterious consequences of financial strain on psychological distress. No such patterns were documented for religious importance.We discuss our findings within the broader religion and health literature as to whether secondary control via a divine power reduces or enhances individual agency and discuss religion/spirituality may be a consistent and valuable coping resource through adversity and suffering. Though it may be challenging to maintain, or increase, religious/spiritual beliefs in the face of adversity, that there were observed benefits to well-being for doing so could serve as insightful guidance for both religious leaders and R/S individuals.

Free-standing electrode (FSE) architectures hold the potential to dramatically increase the gravimetric and volumetric energy density of lithium-ion batteries (LIBs) by eliminating the parasitic dead weight and volume associated with traditional metal foil current collectors. However, current FSE fabrication methods suffer from insufficient mechanical stability, electrochemical performance, or industrial adoptability. Here, we demonstrate a scalable camphene-assisted fabrication method that allows simultaneous casting and templating of FSEs comprising common LIB materials with a performance superior to their foil-cast counterparts. These porous, lightweight, and robust electrodes simultaneously enable enhanced rate performance by improving the mass and ion transport within the percolating conductive carbon pore network and eliminating current collectors for efficient and stable Li

Flow cytometry estimates of genome sizes among species ofDrosophilashow a 3-fold variation, ranging from ∼127 Mb inDrosophila mercatorumto ∼400 Mb inDrosophila cyrtoloma. However, the assembled portion of the Muller F Element (orthologous to the fourth chromosome inDrosophila melanogaster) shows a nearly 14-fold variation in size, ranging from ∼1.3 Mb to > 18 Mb. Here, we present chromosome-level long read genome assemblies for fourDrosophilaspecies with expanded F Elements ranging in size from 2.3 Mb to 20.5 Mb. Each Muller Element is present as a single scaffold in each assembly. These assemblies will enable new insights into the evolutionary causes and consequences of chromosome size expansion.

Thin liquid polymer films can be topographically patterned when polymer/air interfaces are deformed by surface-tension gradients. Toward this end, a recently developed method first photochemically patterns surface-tension gradients along a solid, flat polymer film. On heating to the liquid state, the film initially develops topography reflecting the patterned surface-tension gradients. But capillary leveling and diffusion of the photoproduct oppose this causing the features to eventually decay back to a flat film upon extended thermal annealing. Intuitively, this interplay between competing mechanisms sets a limit on the maximum film deformation during the process. Prior studies show that the initial film thickness, photomask periodicity, and amount of photochemical conversion significantly affect the maximum film deformation. Here, we use a model based on lubrication theory to develop additional insights into this observation. We identify two regimes, capillary-leveling-dominated and photoproduct-diffusion-dominated, wherein the respective dominant mechanism determines the maximum film deformation that can be additionally related to various experimental parameters. Scaling laws for the variation of maximum film deformation and aspect ratio with film thickness and surface-tension pattern periodicity are also developed. Complementary experiments show good agreement with model predictions. Insights into the effect of surface-tension pattern asymmetry on the maximum film deformation are also provided. These findings reveal mechanistic detail and fundamental principles that are useful for controlling the process to form target patterns of interest.

The conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) is a key step in DNA demethylation that is mediated by ten–eleven translocation (TET) enzymes, which require ascorbate/vitamin C. Here, we report the 5hmC landscape of normal hematopoiesis and identify cell type–specific 5hmC profiles associated with active transcription and chromatin accessibility of key hematopoietic regulators. We utilized CRISPR/Cas9 to model TET2 loss-of-function mutations in primary human hematopoietic stem and progenitor cells (HSPC). Disrupted cells exhibited increased colonies in serial replating, defective erythroid/megakaryocytic differentiation, and in vivo competitive advantage and myeloid skewing coupled with reduction of 5hmC at erythroid-associated gene loci. Azacitidine and ascorbate restored 5hmC abundance and slowed or reverted the expansion of TET2-mutant clones in vivo. These results demonstrate the key role of 5hmC in normal hematopoiesis and TET2-mutant phenotypes and raise the possibility of utilizing these agents to further our understanding of preleukemia and clonal hematopoiesis. Significance: We show that 5-hydroxymethylation profiles are cell type–specific and associated with transcriptional abundance and chromatin accessibility across human hematopoiesis. TET2 loss caused aberrant growth and differentiation phenotypes and disrupted 5hmC and transcriptional landscapes. Treatment of TET2 KO HSPCs with ascorbate or azacitidine reverted 5hmC profiles and restored aberrant phenotypes. This article is highlighted in the In This Issue feature, p. 265

Transforming how plastics are made, unmade, and remade through innovative research and diverse partnerships that together foster environmental stewardship is critically important to a sustainable future. Designing, preparing, and implementing polymers derived from renewable resources for a wide range of advanced applications that promote future economic development, energy efficiency, and environmental sustainability are all central to these efforts. In this

The conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) is a key step in DNA demethylation that is mediated by ten–eleven translocation (TET) enzymes, which require ascorbate/vitamin C. Here, we report the 5hmC landscape of normal hematopoiesis and identify cell type–specific 5hmC profiles associated with active transcription and chromatin accessibility of key hematopoietic regulators. We utilized CRISPR/Cas9 to model TET2 loss-of-function mutations in primary human hematopoietic stem and progenitor cells (HSPC). Disrupted cells exhibited increased colonies in serial replating, defective erythroid/megakaryocytic differentiation, and in vivo competitive advantage and myeloid skewing coupled with reduction of 5hmC at erythroid-associated gene loci. Azacitidine and ascorbate restored 5hmC abundance and slowed or reverted the expansion of TET2-mutant clones in vivo. These results demonstrate the key role of 5hmC in normal hematopoiesis and TET2-mutant phenotypes and raise the possibility of utilizing these agents to further our understanding of preleukemia and clonal hematopoiesis.Significance:We show that 5-hydroxymethylation profiles are cell type–specific and associated with transcriptional abundance and chromatin accessibility across human hematopoiesis. TET2 loss caused aberrant growth and differentiation phenotypes and disrupted 5hmC and transcriptional landscapes. Treatment of TET2 KO HSPCs with ascorbate or azacitidine reverted 5hmC profiles and restored aberrant phenotypes.This article is highlighted in the In This Issue feature, p. 265

Supplementary Figure from The Cell Type–Specific 5hmC Landscape and Dynamics of Healthy Human Hematopoiesis and TET2-Mutant Preleukemia

Supplementary Table from The Cell Type–Specific 5hmC Landscape and Dynamics of Healthy Human Hematopoiesis and TET2-Mutant Preleukemia

Supplementary Table 1. Patient clinical characteristics (N=44 patients). *PFS values with a (+) indicate response is ongoing at time of data censoring Abbreviations: cfDNA = cell-free DNA; CR = complete response; GE = gene equivalents per mL; GE junction = gastroesophageal junction; GIN = genome instability number; NSCLC = non-small cell lung cancer; PFS = Progression-free survival; PR = partial response; SBRT = stereotactic body radiation therapy; SCC = squamous cell cancer; SD = stable disease Supplementary Figure 1. GIN values for 6014 samples submitted for noninvasive prenatal testing for which no CNAs were detected using NIPT algorithms. Red dashed line represents the established threshold of a GIN value of 170 based on empirical distribution resulting in no GIN values higher than 170 in this training cohort. Supplementary Figure 2. Values for all baseline samples. Patients are divided based upon clinical response to immunotherapy treatment (response = stable disease for > 9 months or complete or partial response; No response (progressor) = progressive or stable disease {less than or equal to} 9 months; Unevaluable = ongoing stable disease not yet reaching 6 months. Top: GIN values for the baseline sample from each of 44 patients. Bottom: Total cfDNA per mL of plasma collected from each patient. Values represent total genome equivalents (GE) based on a single locus droplet digital PCR assay. There was no difference in GIN (p = 0.0.48) or in GE (p =0.49) between responders (N = 13 patients) and non-responders (N = 27 patients) (Supplementary Table 1). Abbreviations: cfDNA = cell-free DNA; GE = gene equivalents per mL; GIN = genome instability number; PCR = polymerase chain reaction. Supplementary Figure 3. Relationship between the total amount of cfDNA and the GIN in 44 baseline plasma samples. Spearman correlation coefficient = 0.49. Supplementary Figure 4. Overview of Patient 110 where the GIN prediction was discordant with RECIST criteria (stable disease for 4 months (hence labelled as progressor)). A) Genome-wide cfDNA profiles from each of the time points described above each plot. Sequencing reads were assigned to 50 kilobase (kb) non-overlapping segments of the human reference genome. The normalized read counts from each segment of the genome are shown with alternating colors delineating chromosomes. A LOESS regression was performed for each chromosome (white lines). Deviations above and below the median value (dashed black line) indicate amplifications and deletions, respectively. B) GIN values for each collected time point relative to treatment initiation. C) Relative change in CNA-specific z-scores over time, consisent with clonal evolution. Each line corresponds with the genomic locus described by like colored "*" in panel A. Note that the region on Chromosome 9 denoted with the purple * appears in all samples and reflects the GIN; however, the region on Chromosome 14 (green *) decreases over time while the region on Chromosome 12 (pink *) increases in the same samples. Collectively, these data are consistent with clonal selection in the tumor measured in the cfDNA. Supplementary Figure 5. Examples of GIN profiles of eleven patients predicted to be non-responders by GIN (responder defined as achieving SD>9 months, PR or CR). X axis = GIN value; Y axis = day since start of treatment. The data from patient 111 is colored green due to showing neither an increased or decreased GIN upon initial evaluation. Open circles represent measured samples with time relative to the treatment initiation (day 0; x-axis). Black dashed line represents the baseline GIN for each patient. Supplementary Figure 6. An independent cohort of 43 samples was processed through two independent sequencing runs and the GIN calculated for each. Cor=pearson correlation coefficient. Red dashed line represents the linear regression of these data.

Inhibitors of the PD-1/PD-L1/CTLA-4 immune checkpoint pathway have revolutionized cancer treatment. Indeed, some patients with advanced, refractory malignancies achieve durable responses; however, only a subset of patients benefit, necessitating new biomarkers to predict outcome. Interrogating cell-free DNA (cfDNA) isolated from plasma (liquid biopsy) provides a promising method for monitoring response. We describe the use of low-coverage, genome-wide sequencing of cfDNA, validated extensively for noninvasive prenatal testing, to detect tumor-specific copy-number alterations, and the development of a new metric—the genome instability number (GIN)—to monitor response to these drugs. We demonstrate how the GIN can be used to discriminate clinical response from progression, differentiate progression from pseudoprogression, and identify hyperprogressive disease. Finally, we provide evidence for delayed kinetics in responses to checkpoint inhibitors relative to molecularly targeted therapies. Overall, these data demonstrate a proof of concept for using this method for monitoring treatment outcome in patients with cancer receiving immunotherapy.

Previous research has established attitudinal and behavioral health variations in relation to the COVID-19 pandemic, but scholarship on the religious antecedents associated with these outcomes has only recently gained momentum. Rhetoric from some leading conservative Protestants in the U.S. has underplayed the threat of the pandemic and may have contributed to unhealthy pandemic behaviors within this faith tradition. Moreover, previous inquiries have revealed that conservative Protestantism’s otherworldly focus can thwart personal and community health. We use nationally representative data to test the hypotheses that, compared with other religious groups and the non-religious, conservative Protestants will tend to (1) perceive the pandemic as less threatening and (2) engage in riskier pandemic lifestyles. These hypotheses are generally supported net of confounding factors. We conclude that affiliation with a conservative Protestant denomination can undermine public health among this faith tradition’s adherents and may therefore compromise general health and well-being during a pandemic. We discuss the implications of these findings, offer recommendations for pandemic health promotion among conservative Protestants, and delineate promising avenues for future research on this important topic.

We demonstrate the facile synthesis and characterization of stereoregular polysaccharides from the biomass-derived platform molecule levoglucosan via metal-triflate mediated cationic-ring opening polymerization.

Transposable elements (TEs) are selfish DNA sequences that can replicate themselves in their host's genome. Hosts have evolved specialized strategies for mitigating the deleterious consequences of TE activity. In Drosophila, the piRNA pathway is the primary transposable element (TE) control pathway. However, many TEs are only expressed in specific cell types, raising the possibility that transcription factors (TFs) also regulate TEs in a sequence-specific manner. Indeed, recent studies in mammals have identified TF families that regulate TE expression in parallel with small RNA pathways, but the contribution of such factors to TE expression regulation in Drosophila remains poorly understood. We leveraged natural expression variation across genetic backgrounds in wild populations of Drosophila to test the hypothesis that TE expression should correlate with the expression of such trans-acting factors. We analyzed coexpression relationships between individual host genes and TEs while controlling for factors that commonly influence TE expression estimates. Our analysis indicates that the expression of some TFs is predictive of TE expression. We find evidence that some of these factors act as regulators of known TE silencing genes, while others may act by binding TE-derived sequences distributed throughout the genome. These results provide a list of candidates for future examination of host/TE interplay, including studies of TF co-option or instances of TE-mediated expansion of host gene regulatory networks.

This study employed national cross-sectional survey data from the 2021 Crime, Health, and Politics Survey (n = 1578 to 1735) to model traditional cigarette and e-cigarette use as a function of religious affiliation, general religiosity, biblical literalism, religious struggles, and the sense of divine control. Although the odds of abstaining from cigarettes and e-cigarettes were comparable for conservative Protestants and non-affiliates, conservative Protestants were more likely to cut down on cigarettes and e-cigarettes during the pandemic. Religiosity increased the odds of abstaining from cigarettes (not e-cigarettes) and reduced pandemic consumption of cigarettes and e-cigarettes. Biblical literalism was unrelated to abstaining from cigarettes and pandemic changes in cigarette use; however, biblical literalists were more likely to cut e-cigarette use during the pandemic. While the sense of divine control was unrelated to abstaining from cigarettes and e-cigarettes, these beliefs increased the odds of cessation from traditional and e-cigarette use. Finally, our religious struggles index was unrelated to smoking behavior. Our study is among the first to report any association between religion and lower e-cigarette use.

We report a scalable melt blowing method for producing porous nonwoven fibers from model cocontinuous polystyrene/high-density polyethylene polymer blends. While conventional melt compounding of cocontinuous blends typically produces domain sizes ∼1-10 μm, melt blowing these blends into fibers reduces those dimensions up to 35-fold and generates an interpenetrating domain structure. Inclusion of ≤1 wt % of a block copolymer compatibilizer in these blends crucially enables access to smaller domain sizes in the fibers by minimizing thermodynamically-driven blend coarsening inherent to cocontinuous blends. Selective solvent extraction of the sacrificial polymer phase yielded a network of porous channels within the fibers. Fiber surfaces also exhibited pores that percolate into the fiber interior, signifying the continuous and interconnected nature of the final structure. Pore sizes as small as ∼100 nm were obtained, suggesting potential applications of these porous nonwovens that rely on their high surface areas, including various filtration modules.

When tissue biopsy is not medically prudent or tissue is insufficient for molecular testing, alternative methods are needed. Because cell-free DNA (cfDNA) has been shown to provide a representative surrogate for tumor tissue, we sought to evaluate its utility in this clinical scenario. cfDNA was isolated from the plasma of patients and assayed with low-coverage (∼0.3×), genome-wide sequencing. Copy-number alterations (CNA) were identified and characterized using analytic methods originally developed for noninvasive prenatal testing (NIPT) and quantified using the genomic instability number (GIN), a metric that reflects the quantity and magnitude of CNAs across the genome. The technical variability of the GIN was first evaluated in an independent cohort comprising genome-wide sequencing results from 27,754 women who consented to have their samples used for research and whose NIPT results yielded no detected CNAs to establish a detection threshold. Subsequently, cfDNA sequencing data from 96 patients with known cancers but for whom a tissue biopsy could not be obtained are presented. An elevated GIN was detected in 35% of patients and detection rates varied by tumor origin. Collectively, CNAs covered 96.6% of all autosomes. Survival was significantly reduced in patients with an elevated GIN relative to those without. Overall, these data provide a proof of concept for the use of low-coverage, genome-wide sequencing of cfDNA from patients with cancer to obtain relevant molecular information in instances where tissue is difficult to access. These data may ultimately serve as an informative complement to other molecular tests.

Porous structures are ubiquitous in nature due to their advantageous mechanical and transport properties. These structures have inspired various synthetic porous polymer technologies, including lightweight structural materials and membranes. While many manufacturing processes have been developed to generate porous thermoplastics, these usually include hazardous processes, such as high pressures and temperatures, or chemical components. Furthermore, few are compatible with additive manufacturing methods, such as 3D printing. Herein, we introduce bio-derived terpene camphene as a solvent and porogen for the freeze-casting of thermoplastic parts under mild conditions. Enabled by a low melting point (50 °C), camphene is used as a solvent for melt processing camphene-polymer solutions at moderate temperatures that later undergo room-temperature crystallization to template polymer-rich domains. Due to its high vapor pressure, camphene can be sublimed directly from these biphasic structures, resulting in an interconnected microporous polymer structure. Various polymers are demonstrated to be soluble in camphene, including polystyrene, an olefinic elastomer, a polystyrene

Topologically associating domains (TADs) are thought to play an important role in preventing gene misexpression by spatially constraining enhancer–promoter contacts. The deleterious nature of gene misexpression implies that TADs should, therefore, be conserved among related species. Several early studies comparing chromosome conformation between species reported high levels of TAD conservation; however, more recent studies have questioned these results. Furthermore, recent work suggests that TAD reorganization is not associated with extensive changes in gene expression. Here, we investigate the evolutionary conservation of TADs among 11 species of Drosophila. We use Hi-C data to identify TADs in each species and employ a comparative phylogenetic approach to derive empirical estimates of the rate of TAD evolution. Surprisingly, we find that TADs evolve rapidly. However, we also find that the rate of evolution depends on the chromatin state of the TAD, with TADs enriched for developmentally regulated chromatin evolving significantly slower than TADs enriched for broadly expressed, active chromatin. We also find that, after controlling for differences in chromatin state, highly conserved TADs do not exhibit higher levels of gene expression constraint. These results suggest that, in general, most TADs evolve rapidly and their divergence is not associated with widespread changes in gene expression. However, higher levels of evolutionary conservation and gene expression constraints in TADs enriched for developmentally regulated chromatin suggest that these TAD subtypes may be more important for regulating gene expression, likely due to the larger number of long-distance enhancer–promoter contacts associated with developmental genes.

Creation of strong and tough plastics from sustainable and biorenewable resources is a significant challenge in polymer science. This challenge is further complicated when attempting to make these materials using an economically viable process, which is often hindered by the production and availability of chemical feedstocks and the efficiency of the monomer synthesis. Herein, we report the synthesis and characterization of a strong thermoplastic made from 2,3-dihydrofuran (DHF), a monomer made in one step from 1,4-butanediol, a bioalcohol already produced on the plant scale. We developed a green, metal-free cationic polymerization to enable the production of poly(2,3-dihydrofuran) (PDHF) with molecular weights of up to 256 kg/mol at room temperature. Characterization of these polymers showed that PDHF possesses high tensile strength and toughness (70 and 14 MPa, respectively) comparable to commercial polycarbonate, high optical clarity, and good barrier properties to oxygen, carbon dioxide, and water. These properties make this material amenable to a variety of applications, from food packaging to high strength windows. Importantly, we have also developed a facile oxidative degradation process of PDHF, providing an end-of-life solution for PDHF materials.

Many natural organisms, such as fungal hyphae and plant roots, grow at their tips, enabling the generation of complex bodies composed of natural materials as well as dexterous movement and exploration. Tip growth presents an exemplary process by which materials synthesis and actuation are coupled, providing a blueprint for how growth could be realized in a synthetic system. Herein, we identify three underlying principles essential to tip-based growth of biological organisms: a fluid pressure driving force, localized polymerization for generating structure, and fluid-mediated transport of constituent materials. In this work, these evolved features inspire a synthetic materials growth process called extrusion by self-lubricated interface photopolymerization (E-SLIP), which can continuously fabricate solid profiled polymer parts with tunable mechanical properties from liquid precursors. To demonstrate the utility of E-SLIP, we create a tip-growing soft robot, outline its fundamental governing principles, and highlight its capabilities for growth at speeds up to 12 cm/min and lengths up to 1.5 m. This growing soft robot is capable of executing a range of tasks, including exploration, burrowing, and traversing tortuous paths, which highlight the potential for synthetic growth as a platform for on-demand manufacturing of infrastructure, exploration, and sensing in a variety of environments.

Liquid-air interfaces can be deformed by surface-tension gradients to create topography, a phenomenon useful for polymer film patterning. A recently developed method creates these gradients by photochemically patterning a solid polymer film. Heating the film to the liquid state leads to flow driven by the patterned surface-tension gradients, but capillary leveling and diffusion of surface-active species facilitate eventual dissipation of the topography. However, experiments demonstrate that using blends of high- and low-molar-mass polymers can considerably delay the decay in topography. To gain insight into this observation, we develop a model based on lubrication theory that yields coupled nonlinear partial differential equations describing how the film height and species concentrations evolve with time and space. Incorporation of a nonmonotonic disjoining pressure is found to significantly increase the lifetime of topographical features, making the model predictions qualitatively consistent with experiments. A parametric study reveals the key variables controlling the kinetics of film deformation and provides guidelines for photochemically induced Marangoni patterning of polymer films.

This research note advances the religious coping literature by testing whether belief in an evil world conditions the stress-moderating role of scripture reading. Hypotheses are tested with original data from a survey of Black, Hispanic, and White American churchgoers from South Texas (2017–2018; n = 1,115). Our findings show that reading scripture for insights into the future attenuates the positive association between major life events and psychological distress, but only for congregants who do not believe the world is fundamentally evil and sinful. For congregants who believe the world is evil, scripture reading amplifies the association between life events and distress. Whether scriptural coping is beneficial for mental health could be contingent on a believer’s broader assumptions about the nature of the world we live in.

Significant research effort has been directed toward the development of sustainable plastics that are high-performance, bioderived, and/or degrade into nontoxic byproducts in natural or engineered environments (i.e., industrial composting facilities). We report the low cytotoxicity of poly(γ-methyl-e-caprolactone) (PMCL)-based materials and the hydrolysis product of PMCL, sodium 6-hydroxy-4-methylcaproate. The concentration of sodium 6-hydroxy-4-methylcaproate that leads to 50% cell death (TD₅₀) is 179 mM, a value that is similar to that of the hydrolysis product of polycaprolactone and higher than that of the hydrolysis product of polylactide. We also report the degradability of two PMCL materials with different architectures (cross-linked and linear triblock polymers) under simulated industrial composting conditions. These materials reached high degrees of carbon mineralization (>85%) over the course of 120 days as monitored by CO₂ evolution. Finally, we examined the industrial compostability of a new aromatic polyester, poly(salicylic methyl glycolide). This material reached 89% carbon mineralization after 120 days, an important finding given the recalcitrance toward degradation of ubiquitous aromatic polyesters.