bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bennu's Natural Sample Delivery Mechanism: Estimating the Flux of Bennuid Meteors at Earth
Authors: Melikyan R. E. , Clark B. E. , Hergenrother C. W. , Chesley S. R. , Nolan M. C. , Ye Q.‐Z. , Lauretta D. S. 
Published: August 2021

AbstractNASA's OSIRIS‐REx mission observed millimeter‐ to centimeter‐scale pebbles being ejected from the surface of asteroid (101955) Bennu, indicating that Bennu is an active asteroid. About 30% of these particles escape from Bennu, and the minimum orbital intersection distance (MOID) between Bennu and Earth suggest the possibility of a “Bennuid” particle flux at Earth. We characterize the evolution of Bennu's particle stream and potential for meteor flux by simulating weekly particle ejections between the years 1780 and 2135 continuing their dynamical evolution until 2200. Ejections are modeled as a discrete release of 95 particles every week. The meteoroid stream is found to be fully distributed around Bennu's orbital path in years. Individual particles and streams remain associable to Bennu for the entire 420 years simulated. Particle flux at Earth is predicted to begin in 2101, as the Bennu‐Earth MOID reaches minimum values. The year of highest particle flux, 2182, experiences 161 Earth intersections and accounts for 1/4 of our predicted meteors. Our methods can be expanded to study the history and structure of the general meteoroid population and to estimate flux from specific near‐Earth asteroids.
Particulate Organic Matter Distributions in the Water Column of the Chukchi Sea During Late Summer
Authors: Goñi Miguel A. , Juranek Lauren W. , Sipler Rachel E. , Welch Kylie A. 
Published: August 2021

AbstractTwo oceanographic cruises were completed in September 2016 and August 2017 to investigate the distribution of particulate organic matter (POM) across the northeast Chukchi Shelf. Both periods were characterized by highly stratified conditions, with major contrasts in the distribution of regional water masses that impacted POM distributions. Overall, surface waters were characterized by low chlorophyll fluorescence (Chl Fl < 0.8 mg m−3) and particle beam attenuation (cp < 0.3 m−1) values, and low concentrations of particulate organic carbon (POC < 8 mmol m−3), chlorophyll and pheophytin (Chl + Pheo < 0.8 mg m−3), and suspended particulate matter (SPM ∼2 g m−3). Elevated Chl Fl and Chl + Pheo (∼2 mg m−3) values measured at mid‐depths below the pycnocline defined the subsurface chlorophyll maxima (SCM), which exhibited moderate POC (∼10 mmol m−3), cp (∼0.4 m−1) and SPM (∼3 g m−3). In contrast, deeper waters below the pycnocline were characterized by low Chl Fl and Chl + Pheo (∼0.7 mg m−3), high cp (>1.5 m−1) and SPM (>8 g m−3) and elevated POC (>10 mmol m−3). POM compositions from surface and SCM regions of the water column were consistent with contributions from active phytoplankton sources whereas samples from bottom waters were characterized by high Pheo/(Chl + Pheo) ratios (>0.4) indicative of altered phytoplankton detritus. Marked contrasts in POM were observed in both surface and middepth waters during both cruises. Increases in chlorophyll and POC consistent with enhanced productivity were measured in middepth waters during the September 2016 cruise following a period of downwelling‐favorable winds, and in surface waters during the August 2017 cruise following a period of upwelling‐favorable winds.
Modeling Asian Dust Storms Using WRF‐Chem During the DRAGON‐Asia Field Campaign in April 2012
Authors: Kim Kyoung‐Min , Kim Si‐Wan , Choi Myungje , Kim Mijin , Kim Jhoon , Shin Inchul , Kim Jeongeun , Chung Chu‐Yong , Yeo Huidong , Kim Sang‐Woo , Joo Seung Jin , McKeen Stuart A. , Zhang Li 
Published: August 2021

AbstractAsian mineral dust substantially influences air quality as well as weather and climate. It is important to forecast dust storms as a part of air quality modeling to protect public health and minimize the disruption to essential daily routines. In this study, we simulated the dust episodes during the DRAGON‐NE Asia field campaign in April 2012 utilizing the Weather Research and Forecasting model coupled with chemistry (WRF‐Chem) with 5 dust emission options and evaluated the model results with the measurements from multiple instruments including Korean geostationary satellites Geostationary Ocean Color Imager (GOCI) and Meteorological Imager (MI). The model well predicted the dust occurrences, transport, and vertically elevated structure, compared to the satellite aerosol optical depths (AOD), the Aerosol Robotic Network (AERONET) AOD and size distribution parameter Angstrom Exponent (AE), the ground‐based lidar and in‐situ observations. However, the model dust concentration varied depending on the selected dust emission option. The model also did not accurately simulate both AOD and AE. When the model AOD agreed with the AERONET AOD, AE did not agree. In general, the model concentrations were overestimated for large size particles (diameter 6–20 μm) and were underestimated for small size particles (0.5–3.6 μm), compared to the observed aerosol size distributions at surface in Korean Peninsula. Our analysis of the episode suggests that the dust is possibly mixed with the aerosols of anthropogenic origins in the Asian region. Therefore, accurate simulations of both anthropogenic aerosols and dust are helpful for evaluating models in the downwind region of the dust sources.
Building Tangent‐Linear and Adjoint Models for Data Assimilation With Neural Networks
Authors: Hatfield Sam , Chantry Matthew , Dueben Peter , Lopez Philippe , Geer Alan , Palmer Tim 
Published: August 2021

AbstractWe assess the ability of neural network emulators of physical parametrization schemes in numerical weather prediction models to aid in the construction of linearized models required by four‐dimensional variational (4D‐Var) data assimilation. Neural networks can be differentiated trivially, and so if a physical parametrization scheme can be accurately emulated by a neural network then its tangent‐linear and adjoint versions can be obtained with minimal effort, compared with the standard paradigms of manual or automatic differentiation of the model code. Here we apply this idea by emulating the non‐orographic gravity wave drag parametrization scheme in an atmospheric model with a neural network, and deriving its tangent‐linear and adjoint models. We demonstrate that these neural network‐derived tangent‐linear and adjoint models not only pass the standard consistency tests but also can be used successfully to do 4D‐Var data assimilation. This technique holds the promise of significantly easing maintenance of tangent‐linear and adjoint codes in weather forecasting centers, if accurate neural network emulators can be constructed.
Is the Sokal or EUTOS long-term survival (ELTS) score a better predictor of responses and outcomes in persons with chronic myeloid leukemia receiving tyrosine-kinase inhibitors?
Authors: Zhang Xiao-Shuai , Gale Robert Peter , Huang Xiao-Jun , Jiang Qian 
Published: August 2021

AbstractData from 1661 consecutive subjects with chronic-phase chronic myeloid leukemia (CML) receiving initial imatinib (n = 1379) or a 2nd-generation tyrosine-kinase inhibitor (2G-TKI; n = 282) were interrogated to determine whether the Sokal or European Treatment and Outcome Study for CML (EUTOS) long-term survival (ELTS) scores were more accurate responses and outcome predictors. Both scores predicted probabilities of achieving complete cytogenetic response (CCyR), major molecular response (MMR), failure- and progression-free survivals (FFS, PFS), and survival in all subjects and those receiving imatinib therapy. However, the ELTS score was a better predictor of MR4, MR4.5, and CML-related survival than the Sokal score. In subjects receiving 2G-TKI therapy, only the ELTS score accurately predicted probabilities of CCyR, MMR, MR4, FFS, and PFS. In the propensity score matching, subjects classified as intermediate risk by the ELTS score receiving a 2G-TKI had better responses (p < 0.001~0.061), FFS (p = 0.002), and PFS (p = 0.03) but not survival. Our data suggest better overall prediction accuracy for the ELTS score compared with the Sokal score in CML patients, especially those receiving 2G-TKIs. People identified as intermediate risk by the ELTS score may benefit more from initial 2G-TKI therapy in achieving surrogate endpoints but not survival, especially when a briefer interval to stopping TKI therapy is the therapy objective.
Niche partitioning by photosynthetic plankton as a driver of CO2-fixation across the oligotrophic South Pacific Subtropical Ocean
Authors: Duerschlag Julia , Mohr Wiebke , Ferdelman Timothy G , LaRoche Julie , Desai Dhwani , Croot Peter L , Voß Daniela , Zielinski Oliver , Lavik Gaute , Littmann Sten , Martínez-Pérez Clara , Tschitschko Bernhard , Bartlau Nina , Osterholz Helena , Dittmar Thorsten , Kuypers Marcel M M 
Published: August 2021

Abstract
Oligotrophic ocean gyre ecosystems may be expanding due to rising global temperatures [1–5]. Models predicting carbon flow through these changing ecosystems require accurate descriptions of phytoplankton communities and their metabolic activities [6]. We therefore measured distributions and activities of cyanobacteria and small photosynthetic eukaryotes throughout the euphotic zone on a zonal transect through the South Pacific Ocean, focusing on the ultraoligotrophic waters of the South Pacific Gyre (SPG). Bulk rates of CO2 fixation were low (0.1 µmol C l−1 d−1) but pervasive throughout both the surface mixed-layer (upper 150 m), as well as the deep chlorophyll a maximum of the core SPG. Chloroplast 16S rRNA metabarcoding, and single-cell 13CO2 uptake experiments demonstrated niche differentiation among the small eukaryotes and picocyanobacteria. Prochlorococcus abundances, activity, and growth were more closely associated with the rims of the gyre. Small, fast-growing, photosynthetic eukaryotes, likely related to the Pelagophyceae, characterized the deep chlorophyll a maximum. In contrast, a slower growing population of photosynthetic eukaryotes, likely comprised of Dictyochophyceae and Chrysophyceae, dominated the mixed layer that contributed 65–88% of the areal CO2 fixation within the core SPG. Small photosynthetic eukaryotes may thus play an underappreciated role in CO2 fixation in the surface mixed-layer waters of ultraoligotrophic ecosystems.
Microglia as hackers of the matrix: sculpting synapses and the extracellular space
Authors: Crapser Joshua D. , Arreola Miguel A. , Tsourmas Kate I. , Green Kim N. 
Published: August 2021

AbstractMicroglia shape the synaptic environment in health and disease, but synapses do not exist in a vacuum. Instead, pre- and postsynaptic terminals are surrounded by extracellular matrix (ECM), which together with glia comprise the four elements of the contemporary tetrapartite synapse model. While research in this area is still just beginning, accumulating evidence points toward a novel role for microglia in regulating the ECM during normal brain homeostasis, and such processes may, in turn, become dysfunctional in disease. As it relates to synapses, microglia are reported to modify the perisynaptic matrix, which is the diffuse matrix that surrounds dendritic and axonal terminals, as well as perineuronal nets (PNNs), specialized reticular formations of compact ECM that enwrap neuronal subsets and stabilize proximal synapses. The interconnected relationship between synapses and the ECM in which they are embedded suggests that alterations in one structure necessarily affect the dynamics of the other, and microglia may need to sculpt the matrix to modify the synapses within. Here, we provide an overview of the microglial regulation of synapses, perisynaptic matrix, and PNNs, propose candidate mechanisms by which these structures may be modified, and present the implications of such modifications in normal brain homeostasis and in disease.
Metabolic programming in dendritic cells tailors immune responses and homeostasis
Authors: Møller Sofie Hedlund , Wang Limei , Ho Ping-Chih 
Published: August 2021

AbstractIt is being increasingly acknowledged that immune cells depend on certain metabolic traits to perform their functions and that the extracellular environment can influence cell metabolism and vice versa. Dendritic cell (DC) subsets traffic through highly diverse environments from the bone marrow, where they develop, to the various peripheral tissues, where they differentiate and capture antigens, before they migrate to the lymph node to present antigens and prime T cells. It is plausible that DC subsets modulate their stimulatory abilities in response to unique metabolic programming. The metabolic requirements of DCs are just recently being discovered, and subset- and context-specific metabolic phenotypes in DCs are highly intertwined with DC functions. In this review, we present the current knowledge on the intrinsic and extrinsic determinants of DC metabolism, how they regulate DC function with examples from tumor biology and in interaction with the microbiota, and discuss how this can be applied therapeutically.
The MURAL collection of prostate cancer patient-derived xenografts enables discovery through preclinical models of uro-oncology
Authors: Risbridger Gail P. , Clark Ashlee K. , Porter Laura H. , Toivanen Roxanne , Bakshi Andrew , Lister Natalie L. , Pook David , Pezaro Carmel J. , Sandhu Shahneen , Keerthikumar Shivakumar , Quezada Urban Rosalia , Papargiris Melissa , Kraska Jenna , Madsen Heather B. , Wang Hong , Richards Michelle G. , Niranjan Birunthi , O’Dea Samantha , Teng Linda , Wheelahan William , Li Zhuoer , Choo Nicholas , Ouyang John F. , Thorne Heather , Devereux Lisa , Hicks Rodney J. , Sengupta Shomik , Harewood Laurence , Iddawala Mahesh , Azad Arun A. , Goad Jeremy , Grummet Jeremy , Kourambas John , Kwan Edmond M. , Moon Daniel , Murphy Declan G. , Pedersen John , Clouston David , Norden Sam , Ryan Andrew , Furic Luc , Goode David L. , Frydenberg Mark , Lawrence Mitchell G. , Taylor Renea A. 
Published: August 2021

AbstractPreclinical testing is a crucial step in evaluating cancer therapeutics. We aimed to establish a significant resource of patient-derived xenografts (PDXs) of prostate cancer for rapid and systematic evaluation of candidate therapies. The PDX collection comprises 59 tumors collected from 30 patients between 2012–2020, coinciding with availability of abiraterone and enzalutamide. The PDXs represent the clinico-pathological and genomic spectrum of prostate cancer, from treatment-naïve primary tumors to castration-resistant metastases. Inter- and intra-tumor heterogeneity in adenocarcinoma and neuroendocrine phenotypes is evident from bulk and single-cell RNA sequencing data. Organoids can be cultured from PDXs, providing further capabilities for preclinical studies. Using a 1 x 1 x 1 design, we rapidly identify tumors with exceptional responses to combination treatments. To govern the distribution of PDXs, we formed the Melbourne Urological Research Alliance (MURAL). This PDX collection is a substantial resource, expanding the capacity to test and prioritize effective treatments for prospective clinical trials in prostate cancer.
DMRT1-mediated reprogramming drives development of cancer resembling human germ cell tumors with features of totipotency
Authors: Taguchi Jumpei , Shibata Hirofumi , Kabata Mio , Kato Masaki , Fukuda Kei , Tanaka Akito , Ohta Sho , Ukai Tomoyo , Mitsunaga Kanae , Yamada Yosuke , Nagaoka So I , Yamazawa Sho , Ohnishi Kotaro , Woltjen Knut , Ushiku Tetsuo , Ozawa Manabu , Saitou Mitinori , Shinkai Yoichi , Yamamoto Takuya , Yamada Yasuhiro 
Published: August 2021

AbstractIn vivo reprogramming provokes a wide range of cell fate conversion. Here, we discover that in vivo induction of higher levels of OSKM in mouse somatic cells leads to increased expression of primordial germ cell (PGC)-related genes and provokes genome-wide erasure of genomic imprinting, which takes place exclusively in PGCs. Moreover, the in vivo OSKM reprogramming results in development of cancer that resembles human germ cell tumors. Like a subgroup of germ cell tumors, propagated tumor cells can differentiate into trophoblasts. Moreover, these tumor cells give rise to induced pluripotent stem cells (iPSCs) with expanded differentiation potential into trophoblasts. Remarkably, the tumor-derived iPSCs are able to contribute to non-neoplastic somatic cells in adult mice. Mechanistically, DMRT1, which is expressed in PGCs, drives the reprogramming and propagation of the tumor cells in vivo. Furthermore, the DMRT1-related epigenetic landscape is associated with trophoblast competence of the reprogrammed cells and provides a therapeutic target for germ cell tumors. These results reveal an unappreciated route for somatic cell reprogramming and underscore the impact of reprogramming in development of germ cell tumors.
Redox-enabled direct stereoconvergent heteroarylation of simple alcohols
Authors: Liu Yongbing , Tao Ran , Lin Zhi-Keng , Yang Guoqiang , Zhao Yu 
Published: August 2021

AbstractThe direct transformation of racemic feedstock materials to valuable enantiopure compounds is of significant importance for sustainable chemical synthesis. Toward this goal, the radical mechanism has proven uniquely effective in stereoconvergent carbon-carbon bond forming reactions. Here we report a mechanistically distinct redox-enabled strategy for an efficient enantioconvergent coupling of pyrroles with simple racemic secondary alcohols. In such processes, chirality is removed from the substrate via dehydrogenation and reinstalled in the catalytic reduction of a key stabilized cationic intermediate. This strategy provides significant advantage of utilizing simple pyrroles to react with feedstock alcohols without the need for leaving group incorporation. This overall redox-neutral transformation is also highly economical with no additional reagent nor waste generation other than water. In our studies, oxime-derived iridacycle complexes are introduced, which cooperate with a chiral phosphoric acid to enable heteroarylation of alcohols, accessing a wide range of valuable substituted pyrroles in high yield and enantioselectivity.
Gate-tunable plasmons in mixed-dimensional van der Waals heterostructures
Authors: Wang Sheng , Yoo SeokJae , Zhao Sihan , Zhao Wenyu , Kahn Salman , Cui Dingzhou , Wu Fanqi , Jiang Lili , Utama M. Iqbal Bakti , Li Hongyuan , Li Shaowei , Zibrov Alexander , Regan Emma , Wang Danqing , Zhang Zuocheng , Watanabe Kenji , Taniguchi Takashi , Zhou Chongwu , Wang Feng 
Published: August 2021

AbstractSurface plasmons, collective electromagnetic excitations coupled to conduction electron oscillations, enable the manipulation of light–matter interactions at the nanoscale. Plasmon dispersion of metallic structures depends sensitively on their dimensionality and has been intensively studied for fundamental physics as well as applied technologies. Here, we report possible evidence for gate-tunable hybrid plasmons from the dimensionally mixed coupling between one-dimensional (1D) carbon nanotubes and two-dimensional (2D) graphene. In contrast to the carrier density-independent 1D Luttinger liquid plasmons in bare metallic carbon nanotubes, plasmon wavelengths in the 1D-2D heterostructure are modulated by 75% via electrostatic gating while retaining the high figures of merit of 1D plasmons. We propose a theoretical model to describe the electromagnetic interaction between plasmons in nanotubes and graphene, suggesting plasmon hybridization as a possible origin for the observed large plasmon modulation. The mixed-dimensional plasmonic heterostructures may enable diverse designs of tunable plasmonic nanodevices.
Identification of two-dimensional layered dielectrics from first principles
Authors: Osanloo Mehrdad Rostami , Van de Put Maarten L. , Saadat Ali , Vandenberghe William G. 
Published: August 2021

AbstractTo realize effective van der Waals (vdW) transistors, vdW dielectrics are needed in addition to vdW channel materials. We study the dielectric properties of 32 exfoliable vdW materials using first principles methods. We calculate the static and optical dielectric constants and discover a large out-of-plane permittivity in GeClF, PbClF, LaOBr, and LaOCl, while the in-plane permittivity is high in BiOCl, PbClF, and TlF. To assess their potential as gate dielectrics, we calculate the band gap and electron affinity, and estimate the leakage current through the candidate dielectrics. We discover six monolayer dielectrics that promise to outperform bulk HfO2: HoOI, LaOBr, LaOCl, LaOI, SrI2, and YOBr with low leakage current and low equivalent oxide thickness. Of these, LaOBr and LaOCl are the most promising and our findings motivate the growth and exfoliation of rare-earth oxyhalides for their use as vdW dielectrics.
A meta-analysis of the ecological and economic outcomes of mangrove restoration
Authors: Su Jie , Friess Daniel A. , Gasparatos Alexandros 
Published: August 2021

AbstractMangrove restoration has become a popular strategy to ensure the critical functions and economic benefits of this ecosystem. This study conducts a meta-analysis of the peer-reviewed literature on the outcomes of mangrove restoration. On aggregate, restored mangroves provide higher ecosystem functions than unvegetated tidal flats but lower than natural mangrove stands (respectively RR’ = 0.43, 95%CIs = 0.23 to 0.63; RR’ = −0.21, 95%CIs = −0.34 to −0.08), while they perform on par with naturally-regenerated mangroves and degraded mangroves. However, restoration outcomes vary widely between functions and comparative bases, and are mediated by factors such as restoration age, species, and restoration method. Furthermore, mangrove restoration offers positive benefit-cost ratios ranging from 10.50 to 6.83 under variable discount rates (−2% to 8%), suggesting that mangrove restoration is a cost-effective form of ecosystem management. Overall, the results suggest that mangrove restoration has substantial potential to contribute to multiple policy objectives related to biodiversity conservation, climate change mitigation and sustainable development.
Purely one-dimensional ferroelectricity and antiferroelectricity from van der Waals niobium oxide trihalides
Authors: Zhang Lei , Tang Cheng , Sanvito Stefano , Du Aijun 
Published: August 2021

AbstractIntrinsic one-dimensional (1D) ferroelectric materials are rarely reported but are highly sought to break the size limit of nanostructured conventional ferroelectrics. Herein, we report a class of inborn 1D ferroelectric nanowires, namely 1D NbOX3 (X = Cl, Br, and I), that can be directly obtained from experimentally realized van der Waals crystals. In addition to the sizable spontaneous polarization, 1D NbOX3 exhibits low ferroelectric switching barriers, small coercive electric fields, and high critical temperature, governed by the hybridization of the Nb empty d orbitals and the O p orbitals (d0 rule). Moreover, the double-channel structure of 1D NbOX3 also enables the emergence of 1D antiferroelectric metastable states. Our findings not only propose a class of 1D ferroelectric materials toward the development of miniaturized and high-density electronic devices, but also pave an avenue of obtaining intrinsic 1D ferroelectrics from van der Waals crystals.