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Donor–acceptor (D–A)‐conjugated polymers have achieved promising performance metrics in numerous optoelectronic applications that continue to motivate studying structure–property relationships and discovering new materials. Here, the materials toolbox is expanded by synthesizing D–A copolymers where 1,4‐dihydropyrrolo[3,2‐b]pyrrole (DHPP) is directly incorporated into the main chain of D–A copolymers for the first time via direct heteroarylation polymerization. Notably, the synthetic complexity of DHPP‐containing polymers coupled with thieno[3,2‐b]pyrrole‐4,6‐dione (TPD) or 3,6‐bis(2‐thienyl)‐2,5‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione (Th2DPP) comonomers is calculated to be lower compared to many common conjugated polymers synthesized via direct arylation. The electron‐rich nature of DHPPs when coupled with TPD or DPP enables optoelectronic properties to be manipulated, evident by measuring distinctly different absorbance and redox properties. Additionally, these D–A copolymers demonstrate their potential in organic electronic applications, such as electrochromics and organic photovoltaics. The reported DHPP‐alt‐Th2DPP copolymer is the first DHPP‐based colored‐to‐transmissive electrochrome and achieves power conversion efficiencies of ~2.5% when incorporated into bulk heterojunction solar cells. Overall, the synthetic accessibility of DHPP monomers and their propensity to participate in robust polymerizations highlights the value of establishing structure–property relationships of an underutilized scaffold. These fundamental attributes serve to inform and advance efforts in the development of DHPP‐containing copolymers for various applications.

•The “processed foods are unhealthy” heuristic was resilient to visual response bias.•The effect was prevalent and positively associated with food technology neophobia.•The impact of the heuristic on perceived healthiness differed across food categories.•Plants and fish were penalised more than meat for an increase in apparent processing.•Health perceptions largely aligned with Nutri-Score, but with notable exceptions.

Oceanic lithosphere carries volatiles, notably water, into the mantle through subduction at convergent plate boundaries. This subducted water exercises control on the production of magma, earthquakes, formation of continental crust and mineral resources. Identifying different potential fluid sources (sediments, crust and mantle lithosphere) and tracing fluids from their release to the surface has proved challenging1. Atlantic subduction zones are a valuable endmember when studying this deep water cycle because hydration in Atlantic lithosphere, produced by slow spreading, is expected to be highly non-uniform2. Here, as part of a multi-disciplinary project in the Lesser Antilles volcanic arc3, we studied boron trace element and isotopic fingerprints of melt inclusions. These reveal that serpentine—that is, hydrated mantle rather than crust or sediments—is a dominant supplier of subducted water to the central arc. This serpentine is most likely to reside in a set of major fracture zones subducted beneath the central arc over approximately the past ten million years. The current dehydration of these fracture zones coincides with the current locations of the highest rates of earthquakes and prominent low shear velocities, whereas the preceding history of dehydration is consistent with the locations of higher volcanic productivity and thicker arc crust. These combined geochemical and geophysical data indicate that the structure and hydration of the subducted plate are directly connected to the evolution of the arc and its associated seismic and volcanic hazards.

Isolation of high density lipoproteins (HDL) for structural and functional studies typically relies on ultracentrifugation techniques, which are time-consuming and difficult to scale. With emerging interest in the clinical relevance of HDL structure and function to cardiovascular disease, a significant gap exists between current and desirable sample preparation throughput. To enable proteomic studies of HDL with large clinical cohorts, we have developed an affinity enrichment approach that relies on the association of histidine-tagged, lipid free ApoA-I with HDL followed by standard metal chelate chromatography. Characterization of the resulting affinity-enriched ApoA-I associated lipoprotein (AALP) pool using biochemical, electrophoretic, and proteomic analysis demonstrates that the isolated material is closely related in structural features, lipid content, protein complement, and relative protein distribution to HDL isolated by ultracentrifugation using sequential density adjustment. The simplicity of the method provides avenues for high-throughput analysis of HDL associated proteins.

Thick packages of lavas forming seaward‐dipping reflectors (SDRs) are diagnostic features of volcanic passive margins. Despite their significance to continental breakup studies, their formation mechanism is still debated. We use ~22,000 km of high‐quality, depth‐migrated, seismic data to document the three‐dimensional geometry of SDRs offshore South America. We find two types: Type I are planar and occur as fault‐bounded wedges. Type II are characterized by reflections that become more convex‐upward in the downdip direction and terminate against a subhorizontal base. We interpret the transition from Type I to Type II SDRs to represent a continuum from continental rifting to full plate separation with formation of new, subaerially generated, magmatic crust. Type I SDRs formed in half grabens during the stretching of continental crust, while Type II lavas infill the space produced by flexing of the crust due to the solidification of the underlying feeder dikes as the magmatic crust moved away from the spreading center. Type II SDRs vary in length and thickness along the margin. In the north, close to the Paraná flood basalts, they are long (tens of kilometers), reach thicknesses of up to 15 km, and have an across margin width of up to 600 km. To the south the Type II SDRs are thinner with lava lengths of <10 km. We propose that Type II lavas in the north erupted from a subaerial, plate spreading center above the Tristan mantle plume and that the shorter lava flows to the south indicates eruption into water, consistent with a cooler, off‐plume mantle. Two types of seaward‐dipping reflectors occur along the South American Atlantic margin with different geometries dependent on whether they formed in response to tectonic or magmatic breakupType I lavas erupted into synrift grabens during the stretching of the crust, while Type II formed in response to plate separation at a subaerial spreading center, fed by underlying dikesThe Type II lavas are substantially more voluminous offshore of the Paraná LIP and most likely represent part of the Cretaceous subaerial spreading center above a mantle plume

•Liking of different oyster-based products was evaluated in a food truck setting.•Expected liking of raw oysters was positively associated with oyster familiarity.•Expected liking of raw oysters was inversely related with food neophobia.•Food neophobia was not associated with expected liking for cooked products.•Cooking oysters could increase their acceptance and consumption in Sweden.

The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon–driven, functional genomic mouse model of medulloblastoma with ‘humanized’ in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (<5%). Whole-genome sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (<12% diagnostic events were retained at recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy.

We present a 2D P‐wave velocity model from the outer rise region of the Lesser Antilles island arc, the first wide‐angle seismic study of outer rise processes at an Atlantic subduction zone. The survey consists of 46 OBS receivers over a 174 km profile with velocities resolved to 15 km below top basement. The final velocity model, produced through tomographic inversion, shows a clear decrease in the velocity of the lower crust and upper mantle of the incoming plate as it approaches the trench. We attribute this drop to outer rise bend‐related hydration, similar to Pacific cases, but superimposed on spatial variations in hydration generated at the slow‐spreading ridge axis. In thin, tectonically controlled crust formed under magma‐poor spreading conditions the superposition of these sources of hydration results in compressional velocities as low as 6.5 km s−1beneath the PmP reflector. In contrast, segments of crust interpreted as having formed under magma‐rich conditions show velocity reductions and inferred hydrous alteration more like that observed in the Pacific. Hence, variations in the style of crustal accretion, which is observed on 50–100 km length scales both along and across isochrons, is a primary control over the distribution of water within the slab at Atlantic subduction systems. This heterogeneous pattern of water storage within the slab is likely further complicated by along strike variations in outer rise bending, subducting fracture zones and deformation at segment ends and may have important implications for our understanding of long‐term patterns of hazard at Atlantic subduction systems. Subduction zones are locations where one of the Earth's tectonic plates is dragged below the other into the mantle. These are locations of significant seismic and volcanic hazard. Water present in the down‐going plate plays an important role in determining the distribution of these hazards. In well‐studied Pacific subduction zones much of this water enters the down‐going plate as it is deformed just prior to subduction in a region known as the outer rise. This hydration can be estimated using seismic techniques which measure the time energy takes to travel through the plate, with altered “wet” rocks shown to be anonymously slow. As the structure of the crust in the Pacific is relatively uniform this hydration is evenly distributed. At Atlantic subduction zones such as the Lesser Antilles the structure of the subducting plate is more variable due to a poor magma supply at the ridge where it forms, leading to highly deformed and thinner crust. Our seismic experiment shows the subducting plate is extremely wet, having been exposed to two distinct phases of hydration, one during its formation and another across the outer rise. This may be the root‐cause for many of the unusual characteristics of this subduction system. We identify very low mantle P‐wave velocities on the order of 6.5 km s−1in the outer rise region of the Lesser Antilles subduction zoneVelocities are the result of two phases of hydrous alteration during accretion at the Mid‐Atlantic Ridge and bending at the outer riseOur results imply that water distribution within the slab is heterogeneous on 50–100 km length scales We identify very low mantle P‐wave velocities on the order of 6.5 km s−1in the outer rise region of the Lesser Antilles subduction zone Velocities are the result of two phases of hydrous alteration during accretion at the Mid‐Atlantic Ridge and bending at the outer rise Our results imply that water distribution within the slab is heterogeneous on 50–100 km length scales

Subtle structural changes in monomeric building blocks can have an immense effect, whether positive or detrimental, on the resulting properties of conjugated polymers. With this in mind, it is paramount to understand structure–property relationships that serve as the guiding principles for manipulating optical and electrochemical characteristics. Herein, a family of dialkylthiophene-co-propylenedioxythiophene copolymers are synthesized via direct arylation polymerizations, with a key design motif being minimal changes in the structural composition of the propylenedioxythiophene comonomer. Variation in the substitution pattern on the propylene bridge provides insights into the role of stereo- and compositional isomers on the resulting polymer properties. Specifically, time-dependent density functional theory calculations reveal changes in the number and placement of comonomers with varying composition and stereocenters, impacting the calculated absorbance spectra, as evident from calculated absorbance maxima spanning 75 nm, which ultimately manifests in differences in the calculated color. Experimentally, UV–vis absorbance spectroscopy and colorimetry reveal a dependence on the stereo- and regiospecificity, while electrochromic properties, such as contrast and switching times, are not drastically affected by the substitution patterns. Independent of position and functionality, each polymer exhibited a transmittance change greater than 65% at the maximum absorbance wavelength while maintaining the ability to rapidly switch between colored and transmissive states in organic electrolytes. This work highlights how subtle structural changes can manipulate and optimize optical features without sacrificing electrochromic properties such as kinetic switching time and optical contrast. In addition to fundamental insights into monomeric design of propylenedioxythiophene building blocks and their optical and redox characteristics, the results provide an additional structural handle for fine-tuning the observed color of electrochromic polymers.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

We present a high‐resolution 2‐D P‐wave velocity model from a 225‐km‐long active seismic profile, collected over ~60–75 Ma central Atlantic crust. The profile crosses five ridge segments separated by a transform and three nontransform offsets. All ridge discontinuities share similar primary characteristics, independent of the offset. We identify two types of crustal segment. The first displays a classic two‐layer velocity structure with a high gradient Layer 2 (~0.9 s−1) above a lower gradient Layer 3 (0.2 s−1). Here, PmP coincides with the 7.5 km s−1contour, and velocity increases to >7.8 km s−1within 1 km below. We interpret these segments as magmatically robust, with PmP representing a petrological boundary between crust and mantle. The second has a reduced contrast in velocity gradient between the upper and lower crust and PmP shallower than the 7.5 km s−1contour. We interpret these segments as tectonically dominated, with PmP representing a serpentinized (alteration) front. While velocity‐depth profiles fit within previous envelopes for slow‐spreading crust, our results suggest that such generalizations give a misleading impression of uniformity. We estimate that the two crustal styles are present in equal proportions on the floor of the Atlantic. Within two tectonically dominated segments, we make the first wide‐angle seismic identifications of buried oceanic core complexes in mature (>20 Ma) Atlantic Ocean crust. They have a ~20‐km‐wide “domal” morphology with shallow basement and increased upper crustal velocities. We interpret their midcrustal seismic velocity inversions as alteration and rock‐type assemblage contrasts across crustal‐scale detachment faults. We identify that magmatic and tectonic modes of slow Atlantic crustal accretion are distinct and equal, based on seismic characteristicsThe structure of crustal discontinuities is controlled by the accretion mode of neighboring segments, independent of ridge offset and orderTwo buried oceanic core complexes in mature Atlantic Ocean crust are identified, based on their dimensions and seismic structure

The article offers suggestions for the young doctor at the beginning of his or her professional career. Topics discussed include associating with good people of the business deals when doctors buy or sell practices, building a team with a lawyer and accountant who specialize in representing doctors, dealing with the salesperson and investments in the business, importance of vacations high-pressure profession and suggestion to combine vacations with professional meetings.

The article presents experts' opinions about the reasonable restrictive covenants for a dental associate in the U.S. Timothy G. Giroux explains that different states have different covenant laws for associates. He advises an associate not to sign anything that is too restrictive to avoid legal accountability. Another expert, Brandon S. Collier, suggests that the typical restrictive period for an associate is two years.