bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association Between Visual Memory andIn VivoAmyloid and Tau Pathology in Preclinical Autosomal Dominant Alzheimer’s Disease
Authors: Bocanegra Yamile , Fox-Fuller Joshua T. , Baena Ana , Guzmán-Vélez Edmarie , Vila-Castelar Clara , Martínez Jairo , Torrico-Teave Heirangi , Lopera Francisco , Quiroz Yakeel T. 
Published: August 2020

AbstractObjective:Visual memory (ViM) declines early in Alzheimer’s disease (AD). However, it is unclear whether ViM impairment is evident in the preclinical stage and relates to markers of AD pathology. We examined the relationship between ViM performance andin vivomarkers of brain pathology in individuals with autosomal dominant AD (ADAD).Methods:Forty-five cognitively unimpaired individuals from a Colombian kindred with the Presenilin 1 (PSEN1) E280A ADAD mutation (19 carriers and 26 noncarriers) completed the Rey–Osterrieth Complex Figure immediate recall test, a measure of ViM. Cortical amyloid burden and regional tau deposition in the entorhinal cortex (EC) and inferior temporal cortex (IT) were measured using11C-Pittsburgh compound B positron emission tomography (PET) and11F-flortaucipir PET, respectively.Results:Cognitively unimpaired carriers and noncarriers did not differ on ViM performance. Compared to noncarriers, carriers had higher levels of cortical amyloid and regional tau in both the EC and IT. In cognitively unimpaired carriers, greater cortical amyloid burden, higher levels of regional tau, and greater age were associated with worse ViM performance. Only a moderate correlation between regional tau and ViM performance remained after adjusting for verbal memory scores. None of these correlations were observed in noncarriers.Conclusions:Results suggest that AD pathology and greater age are associated with worse ViM performance in ADAD before the onset of clinical symptoms. Further investigation with larger samples and longitudinal follow-up is needed to examine the utility of ViM measures for identifying individuals at high risk of developing dementia later in life.
Order at the margins: The legal construction of interface conflicts over time
Authors: KRISCH NICO , CORRADINI FRANCESCO , REIMERS LUCY LU 
Published: August 2020

AbstractLegal multiplicity in the global realm, and the interface conflicts that ensue from it, are widely thought to have a destabilising effect, blocking the path towards a more integrated and perhaps constitutionalised global order. While this diagnosis may appear plausible if interface conflicts are seen as snapshots and rivalrous institutions as the main actors, it is less convincing if we regard these conflicts as part of social processes of contestation that define the relations between different norms over time. It is also less plausible if actors with other orientations – norm irritation or navigation – are taken into view. This article works towards a more encompassing account, both temporally and as regards actor orientations. It uses two case studies of conflicts at the interface between economic governance and human rights to probe the plausibility of its conjectures. Both cases appear as instances of prolonged norm contestation which, despite continued irresolution of the underlying conflicts as a matter of law, have resulted in a significant reorientation and (partial) consolidation around new interpretations. This suggests that interface conflicts, rather than destabilising the rule of law, may also open a pathway for change in the otherwise rigid structure of the international legal order
Spatial Variations in Disturbance Ionospheric Currents—Inference From 12 Geomagnetic Storms
Authors: Bulusu Jayashree , Archana R. K. , Arora Kusumita 
Published: August 2020

AbstractIn this paper, we investigate the latitudinal and longitudinal variations of the disturbance ionospheric current during 12 geomagnetic storms with Dst ranging between −50 and −130 nT. For this purpose, data from 15 geomagnetic stations along three longitudinal sectors at 70°E, 77°E, and 93°E, ranging from middle to equatorial latitudes in both hemispheres are analyzed. Our study reveals the pattern of PP in the different phases of the storm and the competing effects of PP and Ddyn during the recovery phase of the storms. The PP signatures are mainly comparable across longitudes, irrespective of the strength and phase of the storm. The effect of Ddyn shows a seasonal pattern, which is influenced by the strength of the storm. The location of the antifoci during each storm shows latitudinal variability.
Residual Study: Testing Jupiter Atmosphere Models Against Juno MWR Observations
Authors: Zhang Zhimeng , Adumitroaie Virgil , Allison Michael , Arballo John , Atreya Sushil , Bjoraker Gordon , Bolton Scott , Brown Shannon , Fletcher Leigh N. , Guillot Tristan , Gulkis Samuel , Hodges Amoree , Ingersoll Andrew , Janssen Michael , Levin Steven , Li Cheng , Li Liming , Lunine Jonathan , Misra Sidharth , Orton Glenn , Oyafuso Fabiano , Steffes Paul , Wong Michael H. 
Published: August 2020

AbstractThe Juno spacecraft provides unique close‐up views of Jupiter underneath the synchrotron radiation belts while circling Jupiter in its 53‐day orbits. The microwave radiometer (MWR) onboard measures Jupiter thermal radiation at wavelengths between 1.37 and 50 cm, penetrating the atmosphere to a pressure of a few hundred bars and greater. The mission provides the first measurements of Jupiter's deep atmosphere, down to ~250 bars in pressure, constraining the vertical distributions of its kinetic temperature and constituents. As a result, vertical structure models of Jupiter's atmosphere may now be tested by comparison with MWR data. Taking into account the MWR beam patterns and observation geometries, we test several published Jupiter atmospheric models against MWR data. Our residual analysis confirms Li et al.'s (2017, https://doi.org/10.1002/2017GL073159) result that ammonia depletion persists down to 50–60 bars where ground‐based Very Large Array was not able to observe. We also present an extension of the study that iteratively improves the input model and generates Jupiter brightness temperature maps which best match the MWR data. A feature of Juno's north‐to‐south scanning approach is that latitudinal structure is more easily obtained than longitudinal, and the creation of optimum two‐dimensional maps is addressed in this approach.
Tidally Forced Lee Waves Drive Turbulent Mixing Along the Arctic Ocean Margins
Authors: Fer Ilker , Koenig Zoé , Kozlov Igor E. , Ostrowski Marek , Rippeth Tom P. , Padman Laurie , Bosse Anthony , Kolås Eivind 
Published: August 2020

AbstractIn the Arctic Ocean, limited measurements indicate that the strongest mixing below the atmospherically forced surface mixed layer occurs where tidal currents are strong. However, mechanisms of energy conversion from tides to turbulence and the overall contribution of tidally driven mixing to Arctic Ocean state are poorly understood. We present measurements from the shelf north of Svalbard that show abrupt isopycnal vertical displacements of 10–50 m and intense dissipation associated with cross‐isobath diurnal tidal currents of ∼0.15 m s−1. Energy from the barotropic tide accumulated in a trapped baroclinic lee wave during maximum downslope flow and was released around slack water. During a 6‐hr turbulent event, high‐frequency internal waves were present, the full 300‐m depth water column became turbulent, dissipation rates increased by a factor of 100, and turbulent heat flux averaged 15 W m−2 compared with the background rate of 1 W m−2.
A neural circuit model for human sensorimotor timing
Authors: Egger Seth W. , Le Nhat M. , Jazayeri Mehrdad 
Published: August 2020

AbstractHumans and animals can effortlessly coordinate their movements with external stimuli. This capacity indicates that sensory inputs can rapidly and flexibly reconfigure the ongoing dynamics in the neural circuits that control movements. Here, we develop a circuit-level model that coordinates movement times with expected and unexpected temporal events. The model consists of two interacting modules, a motor planning module that controls movement times and a sensory anticipation module that anticipates external events. Both modules harbor a reservoir of latent dynamics, and their interaction forms a control system whose output is adjusted adaptively to minimize timing errors. We show that the model’s output matches human behavior in a range of tasks including time interval production, periodic production, synchronization/continuation, and Bayesian time interval reproduction. These results demonstrate how recurrent interactions in a simple and modular neural circuit could create the dynamics needed to control timing behavior.
Earthquake transformer—an attentive deep-learning model for simultaneous earthquake detection and phase picking
Authors: Mousavi S. Mostafa , Ellsworth William L. , Zhu Weiqiang , Chuang Lindsay Y. , Beroza Gregory C. 
Published: August 2020

AbstractEarthquake signal detection and seismic phase picking are challenging tasks in the processing of noisy data and the monitoring of microearthquakes. Here we present a global deep-learning model for simultaneous earthquake detection and phase picking. Performing these two related tasks in tandem improves model performance in each individual task by combining information in phases and in the full waveform of earthquake signals by using a hierarchical attention mechanism. We show that our model outperforms previous deep-learning and traditional phase-picking and detection algorithms. Applying our model to 5 weeks of continuous data recorded during 2000 Tottori earthquakes in Japan, we were able to detect and locate two times more earthquakes using only a portion (less than 1/3) of seismic stations. Our model picks P and S phases with precision close to manual picks by human analysts; however, its high efficiency and higher sensitivity can result in detecting and characterizing more and smaller events.
Universal growth of ultra-thin III–V semiconductor single crystals
Authors: Chen Yunxu , Liu Jinxin , Zeng Mengqi , Lu Fangyun , Lv Tianrui , Chang Yuan , Lan Haihui , Wei Bin , Sun Rong , Gao Junfeng , Wang Zhongchang , Fu Lei 
Published: August 2020

AbstractUltra-thin III–V semiconductors, which exhibit intriguing characteristics, such as two-dimensional (2D) electron gas, enhanced electron–hole interaction strength, and strongly polarized light emission, have always been anticipated in future electronics. However, their inherent strong covalent bonding in three dimensions hinders the layer-by-layer exfoliation, and even worse, impedes the 2D anisotropic growth. The synthesis of desirable ultra-thin III–V semiconductors is hence still in its infancy. Here we report the growth of a majority of ultra-thin III–V single crystals, ranging from ultra-narrow to wide bandgap semiconductors, through enhancing the interfacial interaction between the III–V crystals and the growth substrates to proceed the 2D layer-by-layer growth mode. The resultant ultra-thin single crystals exhibit fascinating properties of phonon frequency variation, bandgap shift, and giant second harmonic generation. Our strategy can provide an inspiration for synthesizing unexpected ultra-thin non-layered systems and also drive exploration of III–V semiconductor-based electronics.
Aging alters neural activity at event boundaries in the hippocampus and Posterior Medial network
Authors: Reagh Zachariah M. , Delarazan Angelique I. , Garber Alexander , Ranganath Charan 
Published: August 2020

AbstractRecent research has highlighted a role for the hippocampus and a Posterior Medial cortical network in signaling event boundaries. However, little is known about whether or how these neural processes change over the course of healthy aging. Here, 546 cognitively normal participants 18–88 years old viewed a short movie while brain activity was measured using fMRI. The hippocampus and regions of the Posterior Medial network show increased activity at event boundaries, but these boundary-evoked responses decrease with age. Boundary-evoked activity in the posterior hippocampus predicts performance on a separate test of memory for stories, suggesting that hippocampal activity during event segmentation may be a broad indicator of individual differences in episodic memory ability. In contrast, boundary-evoked responses in the medial prefrontal cortex and middle temporal gyrus increase across the age range. These findings suggest that aging may alter neural processes for segmenting and remembering continuous real-world experiences.
Single-cell analysis uncovers fibroblast heterogeneity and criteria for fibroblast and mural cell identification and discrimination
Authors: Muhl Lars , Genové Guillem , Leptidis Stefanos , Liu Jianping , He Liqun , Mocci Giuseppe , Sun Ying , Gustafsson Sonja , Buyandelger Byambajav , Chivukula Indira V. , Segerstolpe Åsa , Raschperger Elisabeth , Hansson Emil M. , Björkegren Johan L. M. , Peng Xiao-Rong , Vanlandewijck Michael , Lendahl Urban , Betsholtz Christer 
Published: August 2020

AbstractMany important cell types in adult vertebrates have a mesenchymal origin, including fibroblasts and vascular mural cells. Although their biological importance is undisputed, the level of mesenchymal cell heterogeneity within and between organs, while appreciated, has not been analyzed in detail. Here, we compare single-cell transcriptional profiles of fibroblasts and vascular mural cells across four murine muscular organs: heart, skeletal muscle, intestine and bladder. We reveal gene expression signatures that demarcate fibroblasts from mural cells and provide molecular signatures for cell subtype identification. We observe striking inter- and intra-organ heterogeneity amongst the fibroblasts, primarily reflecting differences in the expression of extracellular matrix components. Fibroblast subtypes localize to discrete anatomical positions offering novel predictions about physiological function(s) and regulatory signaling circuits. Our data shed new light on the diversity of poorly defined classes of cells and provide a foundation for improved understanding of their roles in physiological and pathological processes.
Site-specific electrical contacts with the two-dimensional materials
Authors: Wong Lok-Wing , Huang Lingli , Zheng Fangyuan , Thi Quoc Huy , Zhao Jiong , Deng Qingming , Ly Thuc Hue 
Published: August 2020

AbstractElectrical contact is an essential issue for all devices. Although the contacts of the emergent two-dimensional materials have been extensively investigated, it is still challenging to produce excellent contacts. The face and edge type contacts have been applied previously, however a comparative study on the site-specific contact performances is lacking. Here we report an in situ transmission electron microscopy study on the contact properties with a series of 2D materials. By manipulating the contact configurations in real time, it is confirmed that, for 2D semiconductors the vdW type face contacts exhibit superior conductivity compared with the non-vdW type contacts. The direct quantum tunneling across the vdW bonded interfaces are virtually more favorable than the Fowler–Nordheim tunneling across chemically bonded interfaces for contacts. Meanwhile, remarkable area, thickness, geometry, and defect site dependences are revealed. Our work sheds light on the significance of contact engineering for 2D materials in future applications.
Plasmon-driven synthesis of individual metal@semiconductor core@shell nanoparticles
Authors: Kamarudheen Rifat , Kumari Gayatri , Baldi Andrea 
Published: August 2020

AbstractMost syntheses of advanced materials require accurate control of the operating temperature. Plasmon resonances in metal nanoparticles generate nanoscale temperature gradients at their surface that can be exploited to control the growth of functional nanomaterials, including bimetallic and core@shell particles. However, in typical ensemble plasmonic experiments these local gradients vanish due to collective heating effects. Here, we demonstrate how localized plasmonic photothermal effects can generate spatially confined nanoreactors by activating, controlling, and spectroscopically following the growth of individual metal@semiconductor core@shell nanoparticles. By tailoring the illumination geometry and the surrounding chemical environment, we demonstrate the conformal growth of semiconducting shells of CeO2, ZnO, and ZnS, around plasmonic nanoparticles of different morphologies. The shell growth rate scales with the nanoparticle temperature and the process is followed in situ via the inelastic light scattering of the growing nanoparticle. Plasmonic control of chemical reactions can lead to the synthesis of functional nanomaterials otherwise inaccessible with classical colloidal methods, with potential applications in nanolithography, catalysis, energy conversion, and photonic devices.
Direct evidence of secondary reconnection inside filamentary currents of magnetic flux ropes during magnetic reconnection
Authors: Wang Shimou , Wang Rongsheng , Lu Quanming , Fu Huishan , Wang Shui 
Published: August 2020

AbstractMagnetic reconnection is a fundamental plasma process, by which magnetic energy is explosively released in the current sheet to energize charged particles and to create bi-directional Alfvénic plasma jets. Numerical simulations predicted that evolution of the reconnecting current sheet is dominated by formation and interaction of magnetic flux ropes, which finally leads to turbulence. Accordingly, most volume of the reconnecting current sheet is occupied by the ropes, and energy dissipation occurs via multiple relevant mechanisms, e.g., the parallel electric field, the rope coalescence and the rope contraction. As an essential element of the reconnecting current sheet, however, how these ropes evolve has been elusive. Here, we present direct evidence of secondary reconnection in the filamentary currents within the ropes. The observations indicate that secondary reconnection can make a significant contribution to energy conversion in the kinetic scale during turbulent reconnection.
Machine learning-based prediction of acute coronary syndrome using only the pre-hospital 12-lead electrocardiogram
Authors: Al-Zaiti Salah , Besomi Lucas , Bouzid Zeineb , Faramand Ziad , Frisch Stephanie , Martin-Gill Christian , Gregg Richard , Saba Samir , Callaway Clifton , Sejdić Ervin 
Published: August 2020

AbstractPrompt identification of acute coronary syndrome is a challenge in clinical practice. The 12-lead electrocardiogram (ECG) is readily available during initial patient evaluation, but current rule-based interpretation approaches lack sufficient accuracy. Here we report machine learning-based methods for the prediction of underlying acute myocardial ischemia in patients with chest pain. Using 554 temporal-spatial features of the 12-lead ECG, we train and test multiple classifiers on two independent prospective patient cohorts (n = 1244). While maintaining higher negative predictive value, our final fusion model achieves 52% gain in sensitivity compared to commercial interpretation software and 37% gain in sensitivity compared to experienced clinicians. Such an ultra-early, ECG-based clinical decision support tool, when combined with the judgment of trained emergency personnel, would help to improve clinical outcomes and reduce unnecessary costs in patients with chest pain.
HNF4α regulates sulfur amino acid metabolism and confers sensitivity to methionine restriction in liver cancer
Authors: Xu Qing , Li Yuanyuan , Gao Xia , Kang Kai , Williams Jason G. , Tong Lingfeng , Liu Juan , Ji Ming , Deterding Leesa J. , Tong Xuemei , Locasale Jason W. , Li Leping , Shats Igor , Li Xiaoling 
Published: August 2020

AbstractMethionine restriction, a dietary regimen that protects against metabolic diseases and aging, represses cancer growth and improves cancer therapy. However, the response of different cancer cells to this nutritional manipulation is highly variable, and the molecular determinants of this heterogeneity remain poorly understood. Here we report that hepatocyte nuclear factor 4α (HNF4α) dictates the sensitivity of liver cancer to methionine restriction. We show that hepatic sulfur amino acid (SAA) metabolism is under transcriptional control of HNF4α. Knocking down HNF4α or SAA enzymes in HNF4α-positive epithelial liver cancer lines impairs SAA metabolism, increases resistance to methionine restriction or sorafenib, promotes epithelial-mesenchymal transition, and induces cell migration. Conversely, genetic or metabolic restoration of the transsulfuration pathway in SAA metabolism significantly alleviates the outcomes induced by HNF4α deficiency in liver cancer cells. Our study identifies HNF4α as a regulator of hepatic SAA metabolism that regulates the sensitivity of liver cancer to methionine restriction.
Clustering earthquake signals and background noises in continuous seismic data with unsupervised deep learning
Authors: Seydoux Léonard , Balestriero Randall , Poli Piero , Hoop Maarten de , Campillo Michel , Baraniuk Richard 
Published: August 2020

AbstractThe continuously growing amount of seismic data collected worldwide is outpacing our abilities for analysis, since to date, such datasets have been analyzed in a human-expert-intensive, supervised fashion. Moreover, analyses that are conducted can be strongly biased by the standard models employed by seismologists. In response to both of these challenges, we develop a new unsupervised machine learning framework for detecting and clustering seismic signals in continuous seismic records. Our approach combines a deep scattering network and a Gaussian mixture model to cluster seismic signal segments and detect novel structures. To illustrate the power of the framework, we analyze seismic data acquired during the June 2017 Nuugaatsiaq, Greenland landslide. We demonstrate the blind detection and recovery of the repeating precursory seismicity that was recorded before the main landslide rupture, which suggests that our approach could lead to more informative forecasting of the seismic activity in seismogenic areas.
Winner–loser effects overrule aggressiveness during the early stages of contests between pigs
Authors: Oldham Lucy , Camerlink Irene , Arnott Gareth , Doeschl-Wilson Andrea , Farish Marianne , Turner Simon P. 
Published: August 2020

AbstractContest behaviour, and in particular the propensity to attack an unfamiliar conspecific, is influenced by an individual’s aggressiveness, as well as by experience of winning and losing (so called ‘winner–loser effects’). Individuals vary in aggressiveness and susceptibility to winner–loser effects but the relationship between these drivers of contest behaviour has been poorly investigated. Here we hypothesise that the winner–loser effect on initiation of agonistic behaviour (display, non-damaging aggression, biting and mutual fighting) is influenced by aggressiveness. Pigs (n = 255) were assayed for aggressiveness (tendency to attack in resident−intruder tests) and then experienced two dyadic contests (age 10 and 13 weeks). Agonistic behaviour, up to reciprocal fighting, in contest 2 was compared between individuals of different aggressiveness in the RI test and experiences of victory or defeat in contest 1. Winner–loser effects were more influential than aggressiveness in determining initiation of agonistic behaviour. After accruing more skin lesions in contest 1, individuals were less likely to engage in escalated aggression in contest 2. The interaction between aggressiveness and winner–loser experience did not influence contest behaviour. The results suggest that aggressiveness does not compromise learning from recent contest experience and that reducing aggressiveness is unlikely to affect how animals experience winning and losing.