bluuebunny/crossref_metadata_2025_split huggingface dataset:
Constraining magnetic fields in the circumgalactic medium
Authors: Lan 藍鼎文 Ting-Wen , Prochaska J Xavier 
Published: June 2020

ABSTRACTWe study the properties of magnetic fields in the circumgalactic medium (CGM) of z &lt; 1 galaxies by correlating Faraday rotation measures (RMs) of ∼1000 high-redshift radio sources with the foreground galaxy number density estimated from the DESI Legacy Imaging Surveys. This method enables us to extract signals of RMs contributed by intervening gas around multiple galaxies. Our results show that there is no detectable correlation between the distribution of RMs and the number of foreground galaxies, contrary to several previous results. Utilizing the non-detection signals, we estimate 3σ upper limits to the RMs from the CGM of $\sim \!20 \rm \ rad\, m^{-2}$ within 50 kpc and $\sim \!10 \rm \ rad \, m^{-2}$ at separations of 100 kpc. By adopting a column density distribution of ionized gas obtained from absorption-line measurements, we further estimate the strengths of coherent magnetic fields parallel to the line of sight of $\lt \rm 2 \ \mu G$ in the CGM. We show that the estimated upper limits of RMs and magnetic field strengths are sufficient to constrain outputs of recent galaxy magnetohydrodynamic simulations. Finally, we discuss possible causes for the inconsistency between our results and previous works.
Shapley supercluster survey: mapping the dark matter distribution
Authors: Higuchi Yuchi , Okabe Nobuhiro , Merluzzi Paola , Haines Christopher Paul , Busarello Giovanni , Grado Aniello , Mercurio Amata 
Published: June 2020

ABSTRACT
We present a 23 deg2 weak gravitational lensing survey of the Shapley supercluster core and its surroundings using gri VST images as part of the Shapley Supercluster Survey (ShaSS). This study reveals the overall matter distribution over a region containing 11 clusters at z ∼ 0.048 that are all interconnected, as well as several ongoing cluster–cluster interactions. Galaxy shapes have been measured by using the Kaiser–Squires–Broadhurst method for the g- and r-band images and background galaxies were selected via the gri colour–colour diagram. This technique has allowed us to detect all of the clusters, either in the g- or r-band images, although at different σ levels, indicating that the underlying dark matter distribution is tightly correlated with the number density of the member galaxies. The deeper r-band images have traced the five interacting clusters in the supercluster core as a single coherent structure, confirmed the presence of a filament extending North from the core, and have revealed a background cluster at z ∼ 0.17. We have measured the masses of the four richest clusters (A3556, A3558, A3560, and A3562) in the two-dimensional shear pattern, assuming a spherical Navarro–Frenk–White profile and obtaining a total mass of $\mathcal {M}_{\rm ShaSS,WL}{=}1.56^{+0.81}_{-0.55}{\times }10^{15\, }{\rm M}_{\odot }$, which is consistent with dynamical and X-ray studies. Our analysis provides further evidence of the ongoing dynamical evolution in the ShaSS region.
Constraining the inner density slope of massive galaxy clusters
Authors: He Qiuhan , Li Hongyu , Li Ran , Frenk Carlos S , Schaller Matthieu , Barnes David , Bahé Yannick , Kay Scott T , Gao Liang , Dalla Vecchia Claudio 
Published: June 2020

ABSTRACT
We determine the inner density profiles of massive galaxy clusters (M200 &gt; 5 × 1014 M⊙) in the Cluster-EAGLE (C-EAGLE) hydrodynamic simulations, and investigate whether the dark matter density profiles can be correctly estimated from a combination of mock stellar kinematical and gravitational lensing data. From fitting mock stellar kinematics and lensing data generated from the simulations, we find that the inner density slopes of both the total and the dark matter mass distributions can be inferred reasonably well. We compare the density slopes of C-EAGLE clusters with those derived by Newman et al. for seven massive galaxy clusters in the local Universe. We find that the asymptotic best-fitting inner slopes of ‘generalized’ Navarro–Frenk–White (gNFW) profiles, γgNFW, of the dark matter haloes of the C-EAGLE clusters are significantly steeper than those inferred by Newman et al. However, the mean mass-weighted dark matter density slopes of the simulated clusters are in good agreement with the Newman et al. estimates. We also find that the estimate of γgNFW is very sensitive to the constraints from weak lensing measurements in the outer parts of the cluster and a bias can lead to an underestimate of γgNFW.
On the influence of supra-thermal particle acceleration on the morphology of low-Mach, high-β shocks
Authors: van Marle Allard Jan 
Published: June 2020

ABSTRACT
When two galaxy clusters encounter each other, the interaction results in a collisionless shock that is characterized by a low (1–4) sonic Mach number, and a high-Alfvénic Mach number. Our goal is to determine if, and to what extent, such shocks can accelerate particles to sufficient velocities that they can contribute to the cosmic ray spectrum. We combine two different computational methods, magnetohydrodynamics (MHD) and particle-in-cell (PIC) into a single code that allows us to take advantage of the high computational efficiency of MHD while maintaining the ability to model the behaviour of individual non-thermal particles. Using this method, we perform a series of simulations covering the expected parameter space of galaxy cluster collision shocks. Our results show that for shocks with a sonic Mach number below 2.25 no diffusive shock acceleration can take place because of a lack of instabilities in the magnetic field, whereas for shocks with a sonic Mach number $\ge \, 3$ the acceleration is efficient and can accelerate particles to relativistic speeds. In the regime between these two extremes, diffusive shock acceleration can occur but is relatively inefficient because of the time- and space-dependent nature of the instabilities. For those shocks that show efficient acceleration, the instabilities in the upstream gas increase to the point where they change the nature of the shock, which, in turn, will influence the particle injection process.
The Cosmic Ultraviolet Baryon Survey (CUBS) – I. Overview and the diverse environments of Lyman limit systems at z &lt; 1
Authors: Chen Hsiao-Wen , Zahedy Fakhri S , Boettcher Erin , Cooper Thomas M , Johnson Sean D , Rudie Gwen C , Chen Mandy C , Walth Gregory L , Cantalupo Sebastiano , Cooksey Kathy L , Faucher-Giguère Claude-André , Greene Jenny E , Lopez Sebastian , Mulchaey John S , Penton Steven V , Petitjean Patrick , Putman Mary E , Rafelski Marc , Rauch Michael , Schaye Joop , Simcoe Robert A , Weiner Benjamin J 
Published: June 2020

ABSTRACT
We present initial results from the Cosmic Ultraviolet Baryon Survey (CUBS). CUBS is designed to map diffuse baryonic structures at redshift z ≲ 1 using absorption-line spectroscopy of 15 UV-bright QSOs with matching deep galaxy survey data. CUBS QSOs are selected based on their NUV brightness to avoid biases against the presence of intervening Lyman limit systems (LLSs) at zabs &lt; 1. We report five new LLSs of $\log \, N({\mathrm{ H} \,{\small I}})/{{\rm cm^{-2}}}\gtrsim 17.2$ over a total redshift survey path-length of $\Delta \, z_{\mathrm{ LL}}=9.3$, and a number density of $n(z)=0.43_{-0.18}^{+0.26}$. Considering all absorbers with $\log \, N({{\mathrm{ H} \,{\small I}}})/{{\rm cm^{-2}}}\gt 16.5$ leads to $n(z)=1.08_{-0.25}^{+0.31}$ at zabs &lt; 1. All LLSs exhibit a multicomponent structure and associated metal transitions from multiple ionization states such as C ii, C iii, Mg ii, Si ii, Si iii, and O vi absorption. Differential chemical enrichment levels as well as ionization states are directly observed across individual components in three LLSs. We present deep galaxy survey data obtained using the VLT-MUSE integral field spectrograph and the Magellan Telescopes, reaching sensitivities necessary for detecting galaxies fainter than $0.1\, L_*$ at d ≲ 300 physical kpc (pkpc) in all five fields. A diverse range of galaxy properties is seen around these LLSs, from a low-mass dwarf galaxy pair, a co-rotating gaseous halo/disc, a star-forming galaxy, a massive quiescent galaxy, to a galaxy group. The closest galaxies have projected distances ranging from d = 15 to 72 pkpc and intrinsic luminosities from ${\approx} 0.01\, L_*$ to ${\approx} 3\, L_*$. Our study shows that LLSs originate in a variety of galaxy environments and trace gaseous structures with a broad range of metallicities.
Temporospatial genomic profiling in glioblastoma identifies commonly altered core pathways underlying tumor progression
Authors: Blomquist Mylan R , Ensign Shannon Fortin , D’Angelo Fulvio , Phillips Joanna J , Ceccarelli Michele , Peng Sen , Halperin Rebecca F , Caruso Francesca P , Garofano Luciano , Byron Sara A , Liang Winnie S , Craig David W , Carpten John D , Prados Michael D , Trent Jeffrey M , Berens Michael E , Iavarone Antonio , Dhruv Harshil , Tran Nhan L 
Published: June 2020

Abstract

Background
Tumor heterogeneity underlies resistance and disease progression in glioblastoma (GBM), and tumors most commonly recur adjacent to the surgical resection margins in contrast non-enhancing (NE) regions. To date, no targeted therapies have meaningfully altered overall patient survival in the up-front setting. The aim of this study was to characterize intratumoral heterogeneity in recurrent GBM using bulk samples from primary resection and recurrent samples taken from contrast-enhancing (EN) and contrast NE regions.

Methods
Whole exome and RNA sequencing were performed on matched bulk primary and multiple recurrent EN and NE tumor samples from 16 GBM patients who received standard of care treatment alone or in combination with investigational clinical trial regimens.

Results
Private mutations emerge across multi-region sampling in recurrent tumors. Genomic clonal analysis revealed increased enrichment in gene alterations regulating the G2M checkpoint, Kras signaling, Wnt signaling, and DNA repair in recurrent disease. Subsequent functional studies identified augmented PI3K/AKT transcriptional and protein activity throughout progression, validated by phospho-protein levels. Moreover, a mesenchymal transcriptional signature was observed in recurrent EN regions, which differed from the proneural signature in recurrent NE regions.

Conclusions
Subclonal populations observed within bulk resected primary GBMs transcriptionally evolve across tumor recurrence (EN and NE regions) and exhibit aberrant gene expression of common signaling pathways that persist despite standard or targeted therapy. Our findings provide evidence that there are both adaptive and clonally mediated dependencies of GBM on key pathways, such as the PI3K/AKT axis, for survival across recurrences.
Understanding gun culture
Authors: Joslyn Mark R. 
Published: June 2020

Abstract
Chapter 1 introduces a fairly large and diverse literature on gun culture. Gun culture focuses attention on the distinctive meanings that people attach to guns. For some, guns symbolize power and violence, while for others guns signify protection and freedom. These contrasting meanings are central to understanding the deep political divisions about guns that exist in the United States. This chapter covers three different research approaches to gun culture: ethnographic, historical, and quantitative. After a comprehensive presentation of gun culture and the institutional forces that shape it, the author anticipates a substantial gap between gun owners’ and nonowners’ political choices and attitudes.
How many gun owners?
Authors: Joslyn Mark R. 
Published: June 2020

Abstract
Chapter 6 examines survey respondents’ estimations of the actual number of people who own guns in the United States. Evidence from the surveys shows that most people overestimate the gun owner population and believe that the number of owners will increase even further in the next decade. Most, in fact, predict that within the next ten years gun owners will represent a majority of Americans. While most estimates may be inaccurate, they are important because they have consequences for the respondents’ gun policy preferences. Data show that those who overestimate the percentage of gun owners in the United States are notably supportive of gun rights policies.
Conclusion
Authors: Joslyn Mark R. 
Published: June 2020

Abstract
The concluding chapter summarizes two central contributions of the book. First, gun owners merit greater research attention by those who study political behavior and attitudes. The evidence marshaled in the previous chapters strongly support this conclusion. Second, considerable variation within the population of gun owners exists. Once a gun gap is established, there are secondary divisions captured by the number of guns owned that reveal the power of gun culture and gun owner identity. If owning one gun increases the probability of a given political behavior, owning four or more guns will sharply increase those probabilities. Implications of these findings are discussed and future research considered.
Vascular Cognitive Impairment
Authors: Wasserman Victor , Emrani Sheina , Matusz Emily , Price Catherine C. , Lamar Melissa , Swenson Rodney A. , Heilman Kenneth M. , Libon David J. 
Published: June 2020

Abstract
The term vascular cognitive impairment (VCI) was introduced and designed to encompass the broad spectrum of neurocognitive deficits attributable to cerebrovascular disease, including cerebral infarctions and ischemia, that may involve the cerebral cortex, subcortical nuclei, and subcortical white matter, including lacunes (small infarcts that are 3 to 15 mm cerebrospinal fluid–filled cavities in the basal ganglia or white matter) leukoaraiosis (subcortical white matter), and other vascular-related lesions. The resulting impairment can vary, including the signs-symptoms, the clinical course, and disease severity. Whereas there is now agreement that cerebrovascular disease can be a major contributing factor underlying dementia, there is limited agreement about diagnostic criteria and clinical presentations. This chapter seeks to review pertinent literature on VCI as well as to investigate the construct of mild vascular cognitive impairment. This chapter will also briefly review the history of VCI, epidemiological research, neuropsychological signs and symptoms, and recent research regarding biomarkers, as well as public health and treatment issues.
Heterogeneity in Dementia and Mild Cognitive Impairment
Authors: Drabick Deborah A. G. , Rabinowitz Jill 
Published: June 2020

Abstract
Mild cognitive impairment (MCI) and dementia such as Alzheimer’s disease and vascular dementia are heterogeneous conditions that are associated with a chronic course and impairments across a multitude of neurobiological and neuropsychological domains. Until relatively recently, much research has relied on variable-centered techniques (e.g., structural equation modeling, factor analysis, regression) to delineate and study these conditions. This chapter presents evidence of the potential benefits of using person-centered procedures (e.g., latent class analysis) for identifying more homogeneous subgroups of individuals with MCI or dementia that may have distinct correlates, courses, and potential responses to interventions. The research reviewed in this chapter indicates that these strategies permit clinicians and investigators to (a) identify subgroups of individuals who differ in the frequency and/or quality of signs and symptoms, correlates, course, or outcomes, and (b) externally validate and provide support for the predictive validity of these subgroups. Steps for conducting latent class/profile analysis are presented, as well as indices used in selecting the best-fitting model. Implications for assessment, intervention, and future research are provided.
Cerebral Small Vessel Disease and the Risk of Dementia and Cognition Decline
Authors: Salvadori Emilia , Fierini Fabio , Pantoni Leonardo 
Published: June 2020

Abstract
Cerebral small vessel disease (SVD) is well recognized as a highly prevalent disorder that plays an important role in stroke and cognitive impairment. This chapter deals with the relationship between SVD and cognition in longitudinal studies and aims at clarifying the role of SVD as a marker and determinant of neurocognitive impairment. This chapter discusses the prognostic role of magnetic resonance imaging (MRI)-based SVD features (i.e., white matter hyperintensities, small lacunar infarcts, microbleeds, and perivascular spaces) as predictors of dementia or cognitive decline. The evidence reviewed in this chapter provides strong supports for the impact of white matter hyperintensities and small lacunar infarcts in increasing the risk of dementia and cognitive decline. Microbleeds and perivascular spaces have been more recently targeted as MRI features of SVD, and this chapter will review the increasing evidence of their role in cognitive decline.
Structural MRI in Alzheimer’s Disease
Authors: Last Briana S. , Rizvi Batool , Brickman Adam M. 
Published: June 2020

Abstract
Structural magnetic resonance imaging (MRI) is a powerful tool to visualize and quantitate morphological and pathological features of the aging brain. Most work that has used structural MRI to study Alzheimer’s disease (AD) focused on the spatial distribution of atrophic changes associated with disease. These studies consistently show focal atrophy beginning in medial temporal lobes in early and presymptomatic stages of AD before spreading globally throughout the cortical mantle. Normal cognitive aging—aging in the absence of major neurodegenerative disease—on the other hand follows and anterior-to-posterior gradient of atrophic change. In addition to atrophic changes, conventional structural MRI can be used to appreciate markers of small and large vessel cerebrovascular disease, including white matter hyperintensities (WMHs), cerebral microbleeds, and infarction. Studies that have examined cerebrovascular changes associated with AD also show a consistent relationship with risk and severity of clinical AD, particularly with regard to lobar microbleeds and posterior WMH. It is unclear whether cerebrovascular changes play an independent role in the clinical expression of AD or whether it is more mechanistically related, reflecting a core feature of the disease. This chapter reviews recent work on regional atrophy in AD and normal aging, as well as work on small and large cerebrovascular disease in AD.
The Blood–Brain Barrier in Cognitive Decline and Alzheimer’s Disease
Authors: Nation Daniel A. , McIntosh Elissa 
Published: June 2020

Abstract
The neurovascular unit is a multicellular organ that has attracted recent attention as a key microvascular regulator of cerebral blood flow and blood–brain barrier permeability that is implicated in homeostatic and pathological processes impacting cognitive function. Breakdown of the blood–brain barrier invariably causes brain tissue damage and dysfunction due to influx of toxic blood proteins, cells, ions and metals. Clinical studies employing markers of blood–brain barrier permeability suggest an important role in vascular and neurodegenerative dementias. The chapter discusses how the introduction of new neuroimaging and biomarker technologies has opened new pathways of investigation into the blood–brain function in Alzheimer’s disease.
Arterial Stiffening and Cerebrovascular Resistance in Cognitive Decline and Alzheimer’s Disease
Authors: Yew Belinda , Blanken Anna , Nation Daniel A. 
Published: June 2020

Abstract
The impact of vascular factors on cognitive decline and Alzheimer’s disease (AD) has been increasingly recognized. AD and vascular cognitive impairment exhibit significant overlap, individuals with vascular risk factors experience elevated risk for AD, and vascular mechanisms have been implicated in the genetic and pathological processes underlying development of AD. Arterial stiffening and cerebrovascular resistance have been identified as potential junctions through which vascular dysfunction promotes AD pathogenesis and cognitive decline. This chapter outlines the pathophysiology of arterial stiffening and cerebrovascular resistance, beginning in the aorta and small vessels of the brain, respectively. As these processes proliferate, cerebral circulation is disrupted, compromising capacity to meet neuronal metabolic needs and culminating in cognitive declines. An overview is provided of in vivo markers for arterial stiffening and cerebrovascular resistance, including methods employing pulse wave velocity, transcranial Doppler ultrasonography, and arterial spin labeling magnetic resonance imaging. Relevant research developments and their implications for conceptualization of vascular contributions to cognitive decline are discussed.
Unraveling the Role of Mitochondria in Alzheimer’s Disease
Authors: Correia Sónia C. , Moreira Paula I. , Perry George 
Published: June 2020

Abstract
Alzheimer’s disease (AD) is an intriguing and still unsolved puzzle that has attracted, over the last decades, the interest of the scientific community. Despite the limited knowledge regarding the initial cause(s) of AD, mitochondrial abnormalities have been pinpointed as one of the earliest and strongest events related with the pathological course of this complex neurodegenerative disease. In this sense, the present chapter addresses three distinct but connected pieces of the AD puzzle: (a) how could defects of mitochondrial bioenergetics and dynamics contribute to AD pathology? (b) Could mitochondrial defects promote the disease-defining amyloid-β and tau pathologies, and vice versa? and (c) Are mitochondria feasible therapeutic targets to postpone AD symptomatology and neuropathology, and, if so, how and when? The understanding and connection of these puzzle pieces provide a more comprehensive picture about the fundamental role of mitochondrial (mal)function in the neurodegenerative processes that occur in AD and propels future research interventions aimed to forestall AD-related pathological phenotype by bolstering mitochondrial “health.”
Cognitive Change and Elective Surgeries With Anesthesia
Authors: Wiggins Margaret E. , Hernaiz Carlos , Fahy Brenda G. , Price Catherine C. 
Published: June 2020

Abstract
As our lifespan increases, so do the number of older adults who undergo surgeries that require general anesthesia. This poses a significant public health concern; research has highlighted the potential for increasing negative postoperative outcomes (i.e., delirium or postoperative cognitive decline) in the older adult population. Despite this, we currently do not have clear answers about risk factors that make individuals most vulnerable to postoperative changes or how surgical stress can accelerate brain changes, if at all. It is critical that we remain alert to signs of potential neurodegenerative disorders or brain vulnerabilities to implement optimal patient care. These signs may occur at any point during the perioperative process including prior to surgery, during the operative environment, and during postoperative recovery. The present chapter provides an overview of known risk factors at each stage of perioperative care, as well as considerations for neuropsychologists when working with patients in the perioperative environment.
Management of Mild Cognitive Impairment
Authors: Ravona-Springer Ramit , Korczyn Amos D. 
Published: June 2020

Abstract
Mild cognitive impairment (MCI) is a prodromal syndrome often linked to the eventual emergence of dementia syndromes such as Alzheimer’s disease (AD) and vascular dementia (VaD). Research regarding the potential treatment of MCI is reviewed. Current research suggests that neurocognitive decline associated with MCI that may evolve into a dementia syndrome is potentially managed by treating cardiovascular risk factors, appropriate diet and physical exercise, challenging mental activity, intervention for any neuropsychiatric issues, and encouraging meaningful psychosocial relationships. Recent research also suggests potentially better effect on neuropsychological functioning when medication such as donepezil is used to manage both dementia and MCI.