bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biophysical studies of protein misfolding and aggregation in in vivo models of Alzheimer's and Parkinson's diseases
Authors: Sinnige Tessa , Stroobants Karen , Dobson Christopher M. , Vendruscolo Michele 
Published: June 2020

AbstractNeurodegenerative disorders, including Alzheimer's (AD) and Parkinson's diseases (PD), are characterised by the formation of aberrant assemblies of misfolded proteins. The discovery of disease-modifying drugs for these disorders is challenging, in part because we still have a limited understanding of their molecular origins. In this review, we discuss how biophysical approaches can help explain the formation of the aberrant conformational states of proteins whose neurotoxic effects underlie these diseases. We discuss in particular models based on the transgenic expression of amyloid-β (Aβ) and tau in AD, and α-synuclein in PD. Because biophysical methods have enabled an accurate quantification and a detailed understanding of the molecular mechanisms underlying protein misfolding and aggregation in vitro, we expect that the further development of these methods to probe directly the corresponding mechanisms in vivo will open effective routes for diagnostic and therapeutic interventions.
Kinematics of z ∼ 4–6 Lyman break galaxies in ALPINE
Authors: Jones Gareth C. ,   the ALPINE Collaboration
Published: June 2020

AbstractThe past century has seen massive improvements in the study of galaxy kinematics. While early work focused on single nearby galaxies, current studies with modern IFUs and interferometers (e.g., SINFONI, ALMA) allow for extension of this field to high redshift. However, the sample of galaxy observations at z > 4 that feature the sensitivity and resolution required for resolved dynamical characterization has been small. The ALMA Large Program to INvestigate CII at Early times (ALPINE) targeted 118 star-forming galaxies at z = 4–6, representing a vast increase in the sample size of potentially dynamically-characterizable sources. Using a set of diagnostic plots, we are able to characterize roughly half the sample, revealing a vast kinematic diversity and high merger rate. For the nine targets that show rotational signatures, initial tilted ring fitting with 3DBarolo shows promise. With further observations (e.g., ALMA, NOEMA, MUSE), the true nature of each source will be revealed in unprecedented detail.
An evolving photoelectric efficiency at cosmic noon?
Authors: McKinney Jed , Pope Alexandra , Armus Lee , Chary Ranga , Dickinson Mark , Kirkpatrick Allison 
Published: June 2020

AbstractTo sustain star formation rates (SFRs) of hundreds to thousands of solar masses per year over millions of years, a galaxy must efficiently cool its gas. Atz∼ 2, the peak epoch for stellar mass assembly, tracers of gas heating and cooling remain largely unexplored. For onez∼ 2 starburst galaxy GS IRS20, we presentSpitzer IRSspectroscopy of Polycyclic Aromatic Hydrocarbon (PAH) emission, and ALMA observations of [C II] 158μm fine-structure emission which we use to probe ISM heating/cooling. Coupled with an unusually warm dust component, the ratio of [C II] /PAH emission suggests a low photolelectric efficiency, and/or the importance of cooling from other far-IR lines in this galaxy. A low photoelectric efficiency atz∼ 2 could be key for the peak in the SFR density of the universe by decoupling stellar radiation from ISM gas temperatures.
Uncovering the spatial distribution of stars and dust in z ∼ 2 Submillimeter Galaxies
Authors: Lang Philipp , Schinnerer Eva , Smail Ian , Dudzevičiūtė U. , Swinbank A. M. ,   the A3COSMOS, AS2UDS and ALESS Teams
Published: June 2020

AbstractThe spatial distribution of the dust and stars contains crucial information about the evolutionary pathways of galaxies. We present results of our study combing high-resolution ALMA and HST observations of z ∼ 2 bright sub-millimeter galaxies (SMGs). We have developed a two-dimensional extinction and age correction technique to obtain accurate stellar mass distributions from HST/CANDELS. For the first time, we can directly compare the spatial distribution of assembled stellar mass and ongoing star formation on kpc scales for distant SMGs, shedding light on their highly debated formation mechanisms. We find that the dust distribution is more compact than the stellar component, regardless if the SMG lies on the main sequence or at the starburst regime. Taking the dust emission as a proxy for dust-obscured star formation, our results imply that high-redshift SMGs are experiencing centrally enhanced star formation. These findings suggests that major galaxy interactions are not necessarily the main formation channel for SMGs with secular disk formation remaining a viable option as suggested by state-of-the-art cosmological simulations. The sizes and stellar densities of our z ∼ 2 SMGs agree well with the most compact early-type galaxies in the local Universe, strongly supporting the idea that the latter systems are indeed the descendants of massive SMGs at z ∼ 2.
Automated mining of the ALMA archive in the COSMOS field (A3 COSMOS): Cold molecular gas evolution
Authors: Daizhong Liu ,   A3 COSMOS Team
Published: June 2020

AbstractWe present new constraints on the cosmic cold molecular gas evolution out to redshift 6 based on systematic mining of the public ALMA archive in the COSMOS field (A3 COSMOS). Our A3 COSMOS dataset contains ∼ 700 galaxies (0.3 ≲ z ≲ 6) with high-confidence ALMA detection and multi-wavelength SEDs. Combining with ∼ 1,200 CO-observed galaxies at 0 ≲ z ≲ 4 (75% at z < 0.1) in the literature, we parameterize galaxies’ molecular gas depletion time and gas fraction each as a function of stellar mass, offset from the star-forming main-sequence and cosmic age. We propose a new functional form which provides a better fit and implies a “downsizing” effect and “mass-quenching”. By adopting galaxy stellar mass functions and applying our gas fraction function, we obtain a cosmic cold molecular gas density evolution in agreement with recent CO blind field surveys as well as semi-analytic modeling. These together provide us a coherent picture of galaxy cold molecular gas, SFR and stellar mass evolution.
An older, more quiescent universe from panchromatic SED fitting of the 3D-HST survey
Authors: Leja Joel , Johnson Benjamin D. , Conroy Charlie , van Dokkum Pieter , Speagle Joshua S. ,   the 3D-HST Team
Published: June 2020

AbstractGalaxies are complicated physical systems which obey complex scaling relationships; as a result, properties measured from broadband photometry are often highly correlated, degenerate, or both. Therefore, the accuracy of basic properties like stellar masses and star formation rates (SFRs) depend on the accuracy of many second-order galaxy properties, including star formation histories (SFHs), stellar metallicities, dust properties, and many others. Here, we re-assess measurements of galaxy stellar masses and SFRs using a 14-parameter physical model built in the Prospector Bayesian inference framework. We find that galaxies are ∼0.2 dex more massive and have ∼0.2 dex lower star formation rates than classic measurements. These measurements lower the observed cosmic star formation rate density and increase the observed buildup of stellar mass, finally bringing these two metrics into agreement at the factor-of-two level at 0.5 < z < 2.5.
ALPINE: The ALMA [CII] survey of normal star-forming galaxies at 4 <z< 6
Authors: Le Fèvre Olivier , Bethermin Matthieu , Faisst Andreas , Capak P. , Cassata P. , Silverman J. D. , Schaerer D. , Yan L. ,   the ALPINE team
Published: June 2020

AbstractThe ALMA-ALPINE [CII] survey (A2C2S) aims at characterizing the properties of normal star-forming galaxies (SFGs) observed in the [CII]-158μm line in the period of rapid mass assembly at redshifts 4 <z< 6. Here we present the survey and the selection of 118 galaxies observed with ALMA, selected from large samples of galaxies with spectroscopic redshifts derived from UV-rest frame. The observed properties derived from the ALMA data are presented and discussed in terms of the overall detection rate in [CII] and far-IR continuum. The sample is representative of the SFG population at these redshifts. The overall detection rate is 61% down to a flux limit of 0.07 mJy. From a visual inspection of the [CII] data cubes together with the large wealth of ancillary data we find a surprisingly wide range of galaxy types, including 32.4% mergers, 25.7% extended and dispersion dominated, 13.5% rotating discs, and 16.2% compact, the remaining being too faint to be classified. ALPINE sets a reference sample for the gas distribution in normal star-forming galaxies at a key epoch in galaxy assembly, ideally suited for studies with future facilities like JWST and ELTs.
Rapid evolution and transformation into quiescence?: ALMA view on z > 6 low-luminosity quasars
Authors: Izumi Takuma , Onoue Masafusa , Matsuoka Yoshiki , Nagao Tohru , Strauss Michael A. , Imanishi Masatoshi , Kashikawa Nobunari , Fujimoto Seiji , Kohno Kotaro , Toba Yoshiki , Umehata Hideki , Goto Tomotsugu , Ueda Yoshihiro , Shirakata Hikari , Silverman John D. , Greene Jenny E. , Harikane Yuichi , Hashimoto Yasuhiro , Ikarashi Soh , Iono Daisuke , Iwasawa Kazushi , Lee Chien-Hsiu , Minezaki Takeo , Nakanishi Kouichiro , Tamura Yoichi , Tang Ji-Jia , Taniguchi Akio 
Published: June 2020

AbstractWe present ALMA [CII] line and far-infrared (FIR) continuum observations of sevenz> 6 low-luminosity quasars (M1450> −25 mag) discovered by our on-going Subaru Hyper Suprime-Cam survey. The [CII] line was detected in all targets with luminosities of ∼(2−10) × 108L⊙, about one order of magnitude smaller than optically luminous quasars. Also found was a wide scatter of FIR continuum luminosity, ranging fromLFIR< 1011L⊙to ∼2 × 1012L⊙. With the [CII]-based dynamical mass, we suggest that a significant fraction of low-luminosity quasars are located on or even below the local Magorrian relation, particularly at the massive end of the galaxy mass distribution. This is a clear contrast to the previous finding that luminous quasars tend to have overmassive black holes relative to the relation. Our result is expected to show a less-biased nature of the early co-evolution of black holes and their host galaxies.
ALMA twenty-six arcmin2 survey of GOODS-S at one millimeter (ASAGAO)
Authors: Hatsukade B. , Kohno K. , Yamaguchi Y. , Umehata H. , Ao Y. , Aretxaga I. , Caputi K. I. , Dunlop J. S. , Egami E. , Espada D. , Fujimoto S. , Hayatsu N. , Hughes D. H. , Ikarashi S. , Iono D. , Ivison R. J. , Kawabe R. , Kodama T. , Lee M. , Matsuda Y. , Nakanishi K. , Ohta K. , Ouchi M. , Rujopakarn W. , Suzuki T. , Tamura Y. , Ueda Y. , Wang T. , Wang W.-H. , Wilson G. W. , Yoshimura Y. , Yun M. S. ,   ASAGAO team
Published: June 2020

AbstractThe ALMA twenty-six arcmin2 survey of GOODS-S at one millimeter (ASAGAO) is a deep (1σ ∼ 61μJy/beam) and wide area (26 arcmin2) survey on a contiguous field at 1.2 mm. By combining with archival data, we obtained a deeper map in the same region (1σ ∼ 30μJy/beam−1, synthesized beam size 0.59″ × 0.53″), providing the largest sample of sources (25 sources at 5σ, 45 sources at 4.5σ) among ALMA blank-field surveys. The median redshift of the 4.5σ sources is 2.4. The number counts shows that 52% of the extragalactic background light at 1.2 mm is resolved into discrete sources. We create IR luminosity functions (LFs) at z = 1–3, and constrain the faintest luminosity of the LF at 2 < z < 3. The LFs are consistent with previous results based on other ALMA and SCUBA-2 observations, which suggests a positive luminosity evolution and negative density evolution.
New constraints on reionization from a redshift-independent efficiency model
Authors: Potham Naidu Rohan 
Published: June 2020

AbstractWe present an empirical model built on a high-resolution N-body dark matter simulation. We assume a redshift-independent star-formation efficiency for each halo to convert the accretion rate into a star-formation rate. Our model is calibrated using the z = 4 UV luminosity function (UVLF) and successfully predicts the observed UVLF at z = 5 – 10. We present predictions at z = 5 – 10 for UV luminosity and stellar mass functions, JWST number counts, the stellar-to-halo mass relation and star-formation histories. We combine this model with bleeding-edge reionization constraints (from z > 7 quasars, z ∼ 7 Ly α line-profiles, the updated Planck τ) to find new perspectives on the Epoch of Reionization (EoR). We find MUV < − 13.5 galaxies need an average fesc = 0.22 ± 0.05 to drive reionization and a highly compressed timeline: the IGM neutral fraction is [0.9, 0.5, 0.1] at z = [8.4 ± 0.2, 7.0 ± 0.2, 6.3 ± 0.2]. Inspired by the newly assembled sample of Lyman Continuum leakers that unanimously displays higher-than-average star-formation surface density (sigma), we fit a model tying fesc to sigma. Since sigma grows by > 2.5 dex over z = 0 – 8, our model explains the humble values of fesc at low-z. We find, strikingly, that < 5% of galaxies with MUV < − 18 account for > 80% of the reionization budget. We predict leakers like COLA1 (z = 6.6, MUV = − 21.5) become common towards the EoR and that the protagonists of reionization are not hiding across the faint-end of the luminosity function but are already known to us.
ALMA observations of local analogs of high-redshift star-forming galaxies
Authors: Gonçalves Thiago 
Published: June 2020

AbstractI will present the result of two observational projects using ALMA to investigate the properties of the molecular gas in low-redshift (z ∼ 0.2) ultraviolet-luminous galaxies. These objects are extremely dense, highly star-forming and very metal-poor compared to other galaxies of similar stellar mass at the same redshifts, justifying their use as analogues to distant main-sequence galaxies in an attempt to understand the interplay between gas and star formation under similar conditions in the early universe. Firstly, we have observed the most metal-poor objects in our sample, in order to determine whether metallicity plays a role in CO emissivity of the molecular regions in these galaxies. Our four non-detections, with stringent upper limits, shows that CO is severely depleted, even under turbulent conditions. We have also observed one object with high spatial resolution, comparing data from CO emission and hydrogen recombination lines down to a resolution of ∼ 400 pc, allowing for a detailed analysis of the conversion of gas into new stars. We are able to compare star formation laws in individual clumps and the surrounding ISM, highlighting the difference between star formation efficiencies in each environment within the galaxy. Finally, the high-resolution data offers interesting insights on the growth of supermassive black holes in these galaxies: our combined multiwavelength data shows that there must be a low-mass (105 Mȯ) black hole in the center of the galaxy, while bolometric luminosity in the central region is dominated by star formation activity.
Circulation and Thermohaline Variability of the Hanna Shoal Region on the Northeastern Chukchi Sea Shelf
Authors: Fang Ying‐Chih , Weingartner Thomas J. , Dobbins Elizabeth L. , Winsor Peter , Statscewich Hank , Potter Rachel A. , Mudge Todd D. , Stoudt Chase A. , Borg Keath 
Published: June 2020

AbstractWe analyzed velocity and hydrographic data from 23 moorings in the northeast Chukchi Sea from 2011 to 2014. In most years the eastern side of Hanna Shoal was strongly stratified year‐round, while weakly stratified regions prevailed on the shelf south and west of the Shoal. Stratification differences cause differential vertical mixing rates, which in conjunction with advection of different bottom water properties resulted in seasonally varying along‐isobath density gradients. In agreement with numerical models, we find that bottom waters flow anticyclonically around the Shoal. Whereas most of the shelf responded barotropically to wind‐forcing, there was a strong baroclinic component to the flow field northeast of Hanna Shoal, resulting in no net vertically integrated transport on average. In contrast there is a net eastward transport from west of the Shoal, which implies convergence north of the Shoal. Convergence and along‐isobath density gradients may foster cross‐shelf exchange north of Hanna Shoal. Modal analyses indicate that the shelf south of the Shoal and Barrow Canyon responded coherently to local and remote winds, whereas the wind‐current response around Hanna Shoal was less coherent. Barotropic topographic waves, of ~3‐day period, were generated episodically northeast of the Shoal and propagate clockwise around Hanna Shoal, but are blocked from entering Barrow Canyon and are possibly scattered by the horizontally sheared flow and converging isobaths on the western side of the Shoal. Analysis of water properties on the western side of Hanna Shoal suggests that these include contributions from the western and southern portions of the Chukchi Sea.
Bayesian Model Averaging With Fixed and Flexible Priors: Theory, Concepts, and Calibration Experiments for Rainfall‐Runoff Modeling
Authors: Samadi S. , Pourreza‐Bilondi M. , Wilson C. A. M. E. , Hitchcock D. B. 
Published: June 2020

AbstractThis paper introduces for the first time the concept of Bayesian model averaging (BMA) with multiple prior structures, for rainfall‐runoff modeling applications. The original BMA model proposed by Raftery et al. (2005, https://doi.org.10.1175/MWR2906.1) assumes that the prior probability density function (pdf) is adequately described by a mixture of Gamma and Gaussian distributions. Here we discuss the advantages of using BMA with fixed and flexible prior distributions. Uniform, Binomial, Binomial‐Beta, Benchmark, and Global Empirical Bayes priors along with Informative Prior Inclusion and Combined Prior Probabilities were applied to calibrate daily streamflow records of a coastal plain watershed in the southeast United States. Various specifications for Zellner's g prior including Hyper, Fixed, and Empirical Bayes Local (EBL) g priors were also employed to account for the sensitivity of BMA and derive the conditional pdf of each constituent ensemble member. These priors were examined using the simulation results of conceptual and semidistributed rainfall‐runoff models. The hydrologic simulations were first coupled with a new sensitivity analysis model and a parameter uncertainty algorithm to assess the sensitivity and uncertainty associated with each model. BMA was then used to subsequently combine the simulations of the posterior pdf of each constituent hydrological model. Analysis suggests that a BMA based on combined fixed and flexible priors provides a coherent mechanism and promising results for calculating a weighted posterior probability compared to individual model calibration. Furthermore, the probability of Uniform and Informative Prior Inclusion priors received significantly lower predictive error, whereas more uncertainty resulted from a fixed g prior (i.e., EBL).
Characterization of Aerosol Hygroscopicity Over the Northeast Pacific Ocean: Impacts on Prediction of CCN and Stratocumulus Cloud Droplet Number Concentrations
Authors: Schulze B. C. , Charan S. M. , Kenseth C. M. , Kong W. , Bates K. H. , Williams W. , Metcalf A. R. , Jonsson H. H. , Woods R. , Sorooshian A. , Flagan R. C. , Seinfeld J. H. 
Published: June 2020

AbstractDuring the Marine Aerosol Cloud and Wildfire Study (MACAWS) in June and July of 2018, aerosol composition and cloud condensation nuclei (CCN) properties were measured over the N.E. Pacific to characterize the influence of aerosol hygroscopicity on predictions of ambient CCN and stratocumulus cloud droplet number concentrations (CDNC). Three vertical regions were characterized, corresponding to the marine boundary layer (MBL), an above‐cloud organic aerosol layer (AC‐OAL), and the free troposphere (FT) above the AC‐OAL. The aerosol hygroscopicity parameter (κ) was calculated from CCN measurements (κCCN) and bulk aerosol mass spectrometer (AMS) measurements (κAMS). Within the MBL, measured hygroscopicities varied between values typical of both continental environments (~0.2) and remote marine locations (~0.7). For most flights, CCN closure was achieved within 20% in the MBL. For five of the seven flights, assuming a constant aerosol size distribution produced similar or better CCN closure than assuming a constant “marine” hygroscopicity (κ = 0.72). An aerosol‐cloud parcel model was used to characterize the sensitivity of predicted stratocumulus CDNC to aerosol hygroscopicity, size distribution properties, and updraft velocity. Average CDNC sensitivity to accumulation mode aerosol hygroscopicity is 39% as large as the sensitivity to the geometric median diameter in this environment. Simulations suggest CDNC sensitivity to hygroscopicity is largest in marine stratocumulus with low updraft velocities (<0.2 m s−1), where accumulation mode particles are most relevant to CDNC, and in marine stratocumulus or cumulus with large updraft velocities (>0.6 m s−1), where hygroscopic properties of the Aitken mode dominate hygroscopicity sensitivity.
Understanding Reintensified Multiyear El Niño Events
Authors: Kim Ji‐Won , Yu Jin‐Yi 
Published: June 2020

AbstractTo understand the unique temporal evolution of the 2014–2016 multiyear El Niño event, which can be characterized as a successive and reintensified event preceded by a weak El Niño, this study examines similar events in a 2,200‐yr simulation of Community Earth System Model, version 1. By contrasting multiyear El Niño events with single‐year ones, we find that the succession characteristics of multiyear El Niño events are primarily caused by a negative North Pacific Oscillation (NPO) in the first‐year winter via subtropical Pacific coupling processes. By contrasting reintensified multiyear El Niño events with lingering ones, we find that the reintensification characteristics are caused by a negative Indian Ocean Dipole (IOD) in the first‐year fall via tropical interbasin coupling processes. The phase information of the preceding winter NPO and fall IOD together can be used to project the evolution characteristics of El Niño events, particularly the reintensified multiyear and transitional single‐year events.
Global Modeling of Equatorial Spread F with SAMI3/WACCM‐X
Authors: Huba J. D. , Liu H.‐L. 
Published: June 2020

AbstractWe report the first results of a global ionosphere/thermosphere simulation study that self‐consistently generates large‐scale equatorial spread F (ESF) plasma bubbles in the postsunset ionosphere. The coupled model comprises the ionospheric code SAMI3 and the atmosphere/thermosphere code WACCM‐X. Two cases are modeled for different seasons and geophysical conditions: the March case (low solar activity: F10.7 = 70) and the July case (high solar activity: F10.7 = 170). We find that equatorial plasma bubbles formed and penetrated into the topside F layer for the March case but not the July case. For the March case, a series of bubbles formed in the Atlantic sector with irregularity spacings in the range 400–1,200 km, rose to over 800 km, and persisted until after midnight. These results are consistent with recent GOLD observations. Calculation of the generalized Rayleigh‐Taylor instability (GRTI) growth rate shows that the e‐folding time was shorter for the March case than the July case.