Two karrooite crystals, one with a disorder parameter (X = Ti content in the M1 site) of 0.070(5) and the other with X = 0.485(5), were mounted together in one diamond-anvil cell and studied by single-crystal X-ray diffraction at several pressures up to 7.51 GPa. The most noticeable effect of increasing cation disorder on the high-pressure behavior of the structure is to increase the compressibilities of the mean < M12-O > bond length from 0.00148(2) GPa(-1) in the ordered sample to 0.00163(7) GPa(-1) in the disordered one and decrease those of the mean < M1-O > bond length from 0.00243(5) to 0.00193(12) GPa These changes are responsible for the compressibility difference between the two phases observed by Hazen and Yang (1997). Both compressibilities of the mean < M-O > bond lengths and the octahedral volumes in two phases decrease linearly with increasing the Ti contents in the octahedral sites. All octahedra in two samples become less distorted as pressure increases, but those in the more disordered structure exhibit larger decreases in terms of the octahedral angle variance than the corresponding ones in the more ordered structure. The influence of pressure on the interatomic angles is small compared to the interatomic distances, suggesting that compression of the karrooite structure is controlled primarily by the bond-length shortening, rather than by bend-angle bending. The strong compressional anisotropy of the structure is a consequence of the differential compressibilities of the weaker Mg2+-O and stronger Ti4+-O bonds and the complex edge-sharing linkage involving the M1 and M2 octahedra.

Accreting protoplanets are windows into planet formation processes, and high-contrast differential imaging is an effective way to identify them. We report results from the Giant Accreting Protoplanet Survey (GAPlanetS), which collected Ha differential imagery of 14 transitional disk host stars with the Magellan Adaptive Optics System. To address the twin challenges of morphological complexity and point-spread function instability, GAPlanetS required novel approaches for frame selection and optimization of the Karhounen-Loeve Image Processing algorithm pyKLIP. We detect one new candidate, CS Cha "c," at a separation of 68 mas and a modest Delta mag of 2.3. We recover the HD 142527 B and HD 100453 B accreting stellar companions in several epochs, and the protoplanet PDS 70 c in 2017 imagery, extending its astrometric record by nine months. Though we cannot rule out scattered light structure, we also recover LkCa 15 "b," at Ha; its presence inside the disk cavity, absence in Continuum imagery, and consistency with a forward-modeled point source suggest that it remains a viable protoplanet candidate. Through targeted optimization, we tentatively recover PDS 70 c at two additional epochs and PDS 70 b in one epoch. Despite numerous previously reported companion candidates around GAplanetS targets, we recover no additional point sources. Our moderate Ha contrasts do not preclude most protoplanets, and we report limiting Ha contrasts at unrecovered candidate locations. We find an overall detection rate of similar to 36 -22+26%

MOTIVATION: Computational inference of genome organization based on Hi-C sequencing has greatly aided the understanding of chromatin and nuclear organization in three dimensions (3D). However, existing computational methods fail to address the cell population heterogeneity. Here we describe a probabilistic-modeling-based method called CscoreTool-M that infers multiple 3D genome sub-compartments from Hi-C data.

BACKGROUND: Genetic variation in regulatory sequences that alter transcription factor (TF) binding is a major cause of phenotypic diversity. Brassinosteroid is a growth hormone that has major effects on plant phenotypes. Genetic variation in brassinosteroid-responsive cis-elements likely contributes to trait variation. Pinpointing such regulatory variations and quantitative genomic analysis of the variation in TF-target binding, however, remains challenging. How variation in transcriptional targets of signaling pathways such as the brassinosteroid pathway contributes to phenotypic variation is an important question to be investigated with innovative approaches.

Pressing environmental research questions demand the integration of increasingly diverse and large-scale ecological datasets as well as complex analytical methods, which require specialized tools and resources. Computational training for ecological and evolutionary sciences has become more abundant and accessible over the past decade, but tool development has outpaced the availability of specialized training. Most training for scripted analyses focuses on individual analysis steps in one script rather than creating a scripted pipeline, where modular functions comprise an ecosystem of interdependent steps. Although current computational training creates an excellent starting place, linear styles of scripting can risk becoming labor- and time-intensive and less reproducible by often requiring manual execution. Pipelines, however, can be easily automated or tracked by software to increase efficiency and reduce potential errors. Ecology and evolution would benefit from techniques that reduce these risks by managing analytical pipelines in a modular, readily parallelizable format with clear documentation of dependencies. Workflow management software (WMS) can aid in the reproducibility, intelligibility and computational efficiency of complex pipelines. To date, WMS adoption in ecology and evolutionary research has been slow. We discuss the benefits and challenges of implementing WMS and illustrate its use through a case study with the targets r package to further highlight WMS benefits through workflow automation, dependency tracking and improved clarity for reviewers. Although WMS requires familiarity with function-oriented programming and careful planning for more advanced applications and pipeline sharing, investment in training will enable access to the benefits of WMS and impart transferable computing skills that can facilitate ecological and evolutionary data science at large scales.

Detrital chromites are commonly reported within Archean metasedimentary rocks, but have thus far garnered little attention for use in provenance studies. Systematic variations of Cr-Fe spinel mineral chemistry with changing tectonic setting have resulted in the extensive use of chromite as a petrogenetic indicator, and so detrital chromites represent good candidates to investigate the petrogenesis of eroded Archean mafic and ultramafic crust. Here, we report the compositions of detrital chromites within fuchsitic (Cr-muscovite rich) metasedimentary rocks from the Jack Hills, situated within the Narryer Terrane, Yilgarn Craton, Western Australia, which are geologically renowned for hosting Hadean (>4000 Ma) zircons. We highlight signatures of metamorphism, including highly elevated ZnO and MnO, coupled with lowered Mg# in comparison with magmatic chromites, development of pitted domains, and replacement of primary inclusions by phases that are part of the metamorphic assemblages within host metasedimentary rocks. Oxygen isotope compositions of detrital chromites record variable exchange with host metasedimentary rocks. The variability of metamorphic signatures between chromites sampled only meters apart further indicates that modification occurred in situ by interaction of detrital chromites with metamorphic fluids and secondary mineral assemblages. Alteration probably occurred during upper greenschist to lower amphibolite facies metamorphism and deformation of host metasedimentary rocks at similar to 2650 Ma. Regardless of metamorphic signatures, sampling location or grain shape, chromite cores yield a consistent range in Cr#. Although other key petrogenetic indices, such as Fe2O3 and TiO2 contents, are complicated in Jack Hills chromites by mineral non-stoichiometry and secondary mobility within metasedimentary rocks, we demonstrate that the Cr# of chromite yields significant insights into their provenance. Importantly, moderate Cr# (typically 55-70) precludes a komatiitic origin for the bulk of chromites, reflecting a dearth of komatiites and intrusive equivalents within the erosional catchment of the Jack Hills metasedimentary units. We suggest that the Cr# of Jack Hills chromite fits well with chromites derived from layered intrusions, and that a single layered intrusion may account for the observed chemical compositions of Jack Hills detrital chromites. Where detailed characterization of key metamorphic signatures is undertaken, detrital chromites preserved within Archean metasedimentary rocks may therefore yield valuable information on the petrogenesis and geodynamic setting of poorly preserved mafic and ultramafic crust.

The release of phosphorus (P) from crustal rocks during weathering plays a key role in determining the size of Earth's biosphere, yet the concentration of P in crustal rocks over time remains controversial. Here, we combine spatial, temporal, and chemical measurements of preserved rocks to reconstruct the lithological and chemical evolution of Earth's continental crust. We identify a threefold increase in average crustal P concentrations across the Neoproterozoic-Phanerozoic boundary (600 to 400 million years), showing that preferential biomass burial on shelves acted to progressively concentrate P within continental crust. Rapid compositional change was made possible by massive removal of ancient P-poor rock and deposition of young P-rich sediment during an episode of enhanced global erosion. Subsequent weathering of newly P-rich crust led to increased riverine P fluxes to the ocean. Our results suggest that global erosion coupled to sedimentary P-enrichment forged a markedly nutrient-rich crust at the dawn of the Phanerozoic.

There are no planets intermediate in size between Earth and Neptune in our Solar System, yet these objects are found around a substantial fraction of other stars1. Population statistics show that close-in planets in this size range bifurcate into two classes on the basis of their radii2,3. It is proposed that the group with larger radii (referred to as 'sub-Neptunes') is distinguished by having hydrogen-dominated atmospheres that are a few percent of the total mass of the planets4. GJ 1214b is an archetype sub-Neptune that has been observed extensively using transmission spectroscopy to test this hypothesis5-14. However, the measured spectra are featureless, and thus inconclusive, due to the presence of high-altitude aerosols in the planet's atmosphere. Here we report a spectroscopic thermal phase curve of GJ 1214b obtained with the James Webb Space Telescope (JWST) in the mid-infrared. The dayside and nightside spectra (average brightness temperatures of 553±9 and 437±19K, respectively) each show more than 3sigma evidence of absorption features, with H2O as the most likely cause in both. The measured global thermal emission implies that GJ 1214b's Bond albedo is 0.51±0.06. Comparison between the spectroscopic phase curve data and three-dimensional models of GJ 1214b reveal a planet with a high metallicity atmosphere blanketed by a thick and highly reflective layer of clouds or haze.