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There is a longstanding debate over how much idiosyncratic, item-specific knowledge is contained in our mental grammars, in addition to productive knowledge of item-general rules and constraints. A key source of evidence is ordering preferences for syntactic alternations like the dative (“throw him an apple” vs. “throw an apple to him”) vary depending on which words they contain. But the quantitative extent of this variability is poorly understood, especially in relation to superficially similar, non-dative constructions which are not alternating (“throw the man to the floor” vs. “*throw the floor the man”). To address this, we built a large corpus of naturally-occurring sentences including either dative or superficially similar nondative structures, and analyzed the unique contributions of productive and verb-specific knowledge in predicting argument ordering preferences. 

Abstract Pigmentation and colouration are important to animal fitness. Colourations convey important information and impact predation risk, thermoregulation and mate selection. There are many cases of hypopigmentation across the animal kingdom, and leucism is a common form. We observed a Weddell seal (Leptonychotes weddellii) pup with cream-coloured fur, light skin and white nails multiple times in 2022 in Erebus Bay, Antarctica. The pup was observed 1 year later as a generally healthy yearling. This is the first documentation of a leucistic seal within this well-studied population and the second documentation of such colouration in this species. This seal offers a potential opportunity to observe the effects of hypopigmentation in Antarctic true seals. 

Abstract Due to differences between air and debris motions, debris centrifuging creates bias in wind estimates based on Doppler velocities and radar wind retrievals in tornadoes. Anomalous radial divergence, azimuthal wind underestimation, and vertical velocity bias associated with debris centrifuging can lead to erroneous interpretations of tornado intensity and structure from radar data. A novel spectral velocity correction technique is developed to reduce bias by identifying rain and debris motion in radar signals using dual-polarization spectral density estimation and fuzzy logic classification. This technique successfully improves Doppler velocity estimates in simulated S-band polarimetric time series data, although debris concentration modulates both the magnitude and correctability of velocity bias. Large bias magnitudes associated with high debris concentrations are the most difficult to fully correct using this technique, especially at low elevation angles and near the center of the tornado. However, the magnitudes of corrections applied are proportional to the original bias magnitudes, suggesting that the technique performs consistently across low and high debris concentrations. Spectral correction results in an overall 84% reduction in bias in simulations. The spectral correction technique is also applied to dual-polarization S-band radar observations of the 20 May 2013 Moore, Oklahoma tornado. Overall increases in Doppler velocity magnitudes, especially at lower elevation angles, imply that spectral correction can successfully reduce centrifuging bias in observed Doppler velocities. 

Abstract The widely accepted view of the secondary circulation of a mature tropical cyclone (TC) consists of boundary layer inflow that turns upward through the eyewall and then turns outward to form the outflow layer and the cirrus shield. This view can be traced to schematics shown in several foundational studies of TCs and persists in both the peer-reviewed and popular literature in numerous diagrams and cartoons. Updrafts in rainbands are nearly always depicted as not supplying the primary outflow. However, examination of the mass and moisture budgets of the cirrus outflow shield—i.e., the outflow layer from about 100- to 300-km radius—in mesoscale model simulations of hurricanes reveals a different picture. A significant fraction of the dry airmass flux (varying widely but around 50%) and even larger fraction of the condensate in the outflow comes from rainbands. The mass flux from the eyewall is limited by its small size, and condensate is falling out rapidly. Instead, the condensate shield and outflow mass flux are significantly supplied by deep convection in the surrounding rainbands. These findings are consistent with the recently developed appreciation of the diurnally forced rainband complexes that have been shown to expand the cirrus shield. The simulations show that moist air and condensate can be lifted into the outflow in either narrow convective towers or in mesoscale ascending updrafts, and these features can be found in airborne Doppler radar observations. These findings update our understanding of the physical significance of changes in size and thickness of the cirrus shield. Significance StatementTropical cyclones are recognized from satellite images of their high clouds that spiral outward from the storm center. The size and evolution of this outflow are used by experts and algorithms to estimate the intensity and future behavior of these storms. Conventional wisdom holds that the overwhelming source of these high-altitude clouds is the upward transport of moisture in thunderstorms around the calm center. Computer simulations of tropical cyclones and radar observations taken by aircraft show that in fact most of these clouds come from thunderstorms in the surrounding rainbands. These findings highlight the importance of the rainband convection in controlling the size and thickness of the outflow clouds, which in turn inform our estimates of storm intensity. 

Abstract Herein we report the MoO₂Dipic promoted sulfonation of alkenes using N−Ts‐hydroxylamine as the quantitative source of Ts. The reaction works with high yields and stereoselectivities for styrenes with a wide variety of substitution patterns. A novel atom transfer radical addition mechanism involving the formation of molybdooxaziridine complex1as the active catalyst, difunctionalization withTs‐NO, followed by oxidation, and then elimination as the rate‐determining‐step for the formation of vinylsulfone3has been proposed. Initial kinetic and mechanistic data indicates the formation ofTs‐NOand provides evidence for the proposed mechanism. 

This study investigates sentence processing in Standard Arabic (SA) by examining subject- and object-extracted relative clauses (SRCs and ORCs) through eye tracking. We test memory- and expectation-based theories of processing difficulty, and whether good-enough or noisy-channel processing leads to misinterpretations in ORCs. Our results find increased processing difficulty in ORCs, supporting expectation-based theories; however, this processing difficulty is not localized to the disambiguating region (relative clause verb) as predicted, but rather at the integration of the second noun phrase (relative clause NP). The findings support goodenough/noisy-channel processing theories, suggesting that readers may accept a noisy SRC interpretation of an ORC, and thus bypass integration costs at the RC NP. 

This study investigates sentence processing in Standard Arabic (SA) by examining subject- and object-extracted relative clauses (SRCs and ORCs) through eye tracking. We test memory- and expectation-based theories of processing difficulty, and whether good-enough or noisy-channel processing leads to misinterpretations in ORCs. Our results find increased processing difficulty in ORCs, supporting expectation-based theories; however, this processing difficulty is not localized to the disambiguating region (relative clause verb) as predicted, but rather at the integration of the second noun phrase (relative clause NP). The findings support goodenough/noisy-channel processing theories, suggesting that readers may accept a noisy SRC interpretation of an ORC, and thus bypass integration costs at the RC NP. 

In the manufacture of semiconductor devices, cracking of heterostructures has been recognized as a major obstacle for their post-growth processing. In this work, we explore cracked GaN/AlN multi-quantum wells (MQWs) to study the influence of pressure on the recombination energy of the photoluminescence (PL) from the polar GaN QWs. We grow GaN/AlN MQWs on a GaN(0001)/sapphire template, which provides 2.4% tensile strain for epitaxial AlN. This strain relaxes through the generation and propagation of cracks, resulting in a final inhomogeneous distribution of stress throughout the film. The crack-induced strain variation investigated by micro-Raman spectroscopy and X-ray diffraction mapping revealed a correlation between the spacing of the cracks and the amount of strain between them. We have developed a 2D model that allows us to calculate the spatial variation of the in-plane strain in the GaN and AlN layers. The measured values of compressive in-plane strain in the GaN QWs vary from -0.4 % away from cracks, to -0.7 % near cracks. PL from the GaN QWs exhibits a clear correlation to the varying strain resulting in an energy shift of ∼ 140 meV. As a result, we can experimentally calculate a pressure coefficient of PL energy of ∼ -60.4 meV/GPa for the ∼ 7 nm thick polar GaN QWs. This agrees well with the previously predicted theoretical results by Kaminska et al. in 2016 [DOI: 10.1063/1.4962282], which were demonstrated to break down for such wide QWs. We will discuss this difference with respect to the reduction in both the expected point defects and extended defects resulting from not doping and growth on a GaN template, respectively. As a result, our work indicates that cracks can be utilized for investigating some fundamental material properties related to strain effects. 

EndofungalMycetohabitans(formerlyBurkholderia) spp. rely on a type III secretion system to deliver mostly unidentified effector proteins when colonizing their host fungus,Rhizopus microsporus. The one known secreted effector family fromMycetohabitansconsists of homologues of transcription activator-like (TAL) effectors, which are used by plant pathogenicXanthomonasandRalstoniaspp. to activate host genes that promote disease. These ‘BurkholderiaTAL-like (Btl)’ proteins bind corresponding specific DNA sequences in a predictable manner, but their genomic target(s) and impact on transcription in the fungus are unknown. Recent phenotyping of Btl mutants of twoMycetohabitansstrains revealed that the single Btl in oneMycetohabitans endofungorumstrain enhances fungal membrane stress tolerance, while others in aMycetohabitans rhizoxinicastrain promote bacterial colonization of the fungus. The phenotypic diversity underscores the need to assess the sequence diversity and, given that sequence diversity translates to DNA targeting specificity, the functional diversity of Btl proteins. Using a dual approach to maximize capture of Btl protein sequences for our analysis, we sequenced and assembled nineMycetohabitansspp. genomes using long-read PacBio technology and also mined available short-read Illumina fungal–bacterial metagenomes. We show thatbtlgenes are present across diverseMycetohabitansstrains from Mucoromycota fungal hosts yet vary in sequences and predicted DNA binding specificity. Phylogenetic analysis revealed distinct clades of Btl proteins and suggested thatMycetohabitansmight contain more species than previously recognized. Within our data set, Btl proteins were more conserved acrossM. rhizoxinicastrains than acrossM. endofungorum, but there was also evidence of greater overall strain diversity within the latter clade. Overall, the results suggest that Btl proteins contribute to bacterial–fungal symbioses in myriad ways. 

The de novo design of small molecule–binding proteins has seen exciting recent progress; however, high-affinity binding and tunable specificity typically require laborious screening and optimization after computational design. We developed a computational procedure to design a protein that recognizes a common pharmacophore in a series of poly(ADP-ribose) polymerase–1 inhibitors. One of three designed proteins bound different inhibitors with affinities ranging from <5 nM to low micromolar. X-ray crystal structures confirmed the accuracy of the designed protein-drug interactions. Molecular dynamics simulations informed the role of water in binding. Binding free energy calculations performed directly on the designed models were in excellent agreement with the experimentally measured affinities. We conclude that de novo design of high-affinity small molecule–binding proteins with tuned interaction energies is feasible entirely from computation.