bluuebunny/crossref_metadata_2025 huggingface dataset:
Make the Most of Your SCADA System
Authors: Capano Daniel
Published: August 2020

Reliable, efficient monitoring of water treatment plant operations is a must. Supervisory control and data acquisition systems provide such capabilities, but it's vital for operators to understand these powerful systems as well as their own role in maintaining them.
Dihydrolipoamide dehydrogenase moonlighting activity as a DNA chelating agent
Authors: Dayan Avraham , Yeheskel Adva , Lamed Raphael , Fleminger Gideon , Ashur‐Fabian Osnat
Published: August 2020

Dihydrolipoamide dehydrogenase (DLDH) is a mitochondrial enzyme that comprises an essential component of the pyruvate dehydrogenase complex. Lines of evidence have shown that many dehydrogenases possess unrelated actions known as moonlightings in addition to their oxidoreductase activity. As part of these activities, we have demonstrated that DLDH binds TiO2 as well as produces reactive oxygen species (ROS). This ROS production capability was harnessed for cancer therapy via integrin‐mediated drug‐delivery of RGD‐modified DLDH (DLDHRGD), leading to apoptotic cell death. In these experiments, DLDHRGD not only accumulated in the cytosol but also migrated to the cell nuclei, suggesting a potential DNA‐binding capability of this enzyme. To explore this interaction under cell‐free conditions, we have analyzed DLDH binding to phage lambda (λ) DNA by gel‐shift assays and analytic ultracentrifugation, showing complex formation between the two, which led to full coverage of the DNA molecule with DLDH molecules. DNA binding did not affect DLDH enzymatic activity, indicating that there are neither conformational changes nor active site hindering in DLDH upon DNA‐binding. A Docking algorithm for prediction of protein‐DNA complexes, Paradoc, identified a putative DNA binding site at the C‐terminus of DLDH. Our finding that TiO2‐bound DLDH failed to form a complex with DNA suggests partial overlapping between the two sites. To conclude, DLDH binding to DNA presents a novel moonlight activity which may be used for DNA alkylating in cancer treatment.
Atomic structure of Co92−xBxTa8 glassy alloys studied by ab initio molecular dynamics simulations
Authors: Ma Di , Zhang Jing , Di Yaxin , Wang Jianfeng , Guan Shaokang , Zhang Tao
Published: August 2020

The ab initio molecular dynamics simulations were adopted to study the atomic structures of Co92−xBxTa8 (x = 30, 32.5, 35, 37.5, at%) glassy alloys. The results showed that the local packing of B‐centered clusters was more efficient than that of Co‐ and Ta‐centered clusters. It was also found that B‐centered clusters were the primary structure‐forming clusters. The Kasper polyhedra with a Voronoi index of <0 3 6 0> and <0 2 8 0> are dominant in B‐centered clusters. The <0 3 6 0> clusters could especially be formed into a robust network structure, which plays a key role in the increase of mechanical properties. Such a network structure has a higher activation barrier for structural rearrangement and a larger resistance to plastic flow. Thus, the increase in the fraction of <0 3 6 0> with B content would result in an increase in yield strength, as well as a sharp decrease in compressive plasticity.
Model‐free adaptive control for a class of nonlinear systems with uniform quantizer
Authors: Bu Xuhui , Zhu Panpan , Yu Qiongxia , Hou Zhongsheng , Liang Jiaqi
Published: August 2020

The problem of model‐free adaptive control (MFAC) design for a class of nonlinear systems with data quantization is considered in this article. Consider the case that the system output signal should be quantized before being transmitted to the controller. A MFAC algorithm with uniform quantizer is first proposed. As a result, the proposed MFAC algorithm cannot obtain a zero‐tracking error because of the reduction of available information due to data quantization. To suppress the influence of data quantization, an improved MFAC algorithm with encoding and decoding mechanism is proposed. The improved design first encodes the system information and then transmits it through the network. Then, the controller receives the information and then decodes it to construct the MFAC algorithm. Theoretical result shows that the improved MFAC algorithm with encoding and decoding mechanism can obtain the aim of zero‐tracking error. Finally, there have two examples to verify the effectiveness and applicability of the quantized MFAC algorithm design.
Anisotropy of subsoil pore characteristics and hydraulic conductivity as affected by compaction and cover crop treatments
Authors: Pulido‐Moncada Mansonia , Labouriau Rodrigo , Kesser Merek , Zanini Pedro Paulo Gonçalves , Guimarães Rachel Muylaert Locks , Munkholm Lars J.
Published: August 2020

The natural and cover crop (CC)‐induced anisotropy of subsoil pore characteristics is important in assessments of soil compaction but, until recently, has received limited attention. This study aims to quantify the anisotropy of soil pore characteristics and hydraulic conductivity in subsoils subjected to compaction and CC treatments in a split‐plot field experiment on temperate sandy loam soils. The main factor was ±compaction and the split‐plot factor was ±CC with fodder radish (Raphanus sativus L.). The compacted plots were heavily trafficked for 4 yr (2010–2013). After 4 yr under CC (2013–2016), core samples were collected at 0.3 m. The samples were taken vertically and horizontally to quantify the anisotropy of air‐filled porosity (εa) and air permeability (ka), saturated hydraulic conductivity (ksat), and bulk density (ρb). The results showed isotropic behavior for ρb and εa and significant anisotropic behavior (p < .05) for ka, pore geometry index (PO1) (ka/εa), ratio of non‐Darcian to Darcian ka (R‐ratio), and ksat. For parameters with significant anisotropy, higher values occurred vertically than horizontally for all compaction –CC combinations, except for R‐ratio. This indicates that pre‐existing vertical continuous pores dominated the pore system in the control subsoil. A nonsignificant trend of higher values of ka, PO1, and ksat in the +CC than in the compacted –CC plots suggest that CC could contribute to the formation of vertical biopores. Including an autumn CC in rotation with a summer cereal crop for a longer period may significantly affect the anisotropy of the soil pore and hydraulic properties.
Restricted mean survival time for interval‐censored data
Authors: Zhang Chenyang , Wu Yuanshan , Yin Guosheng
Published: August 2020

Restricted mean survival time (RMST) evaluates the mean event‐free survival time up to a prespecified time point. It has been used as an alternative measure of treatment effect owing to its model‐free structure and clinically meaningful interpretation of treatment benefit for right‐censored data. In clinical trials, another type of censoring called interval censoring may occur if subjects are examined at several discrete time points and the survival time falls into an interval rather than being exactly observed. The missingness of exact observations under interval‐censored cases makes the nonparametric measure of treatment effect more challenging. Employing the linear smoothing technique to overcome the ambiguity, we propose a new model‐free measure for the interval‐censored RMST. As an alternative to the commonly used log‐rank test, we further construct a hypothesis testing procedure to assess the survival difference between two groups. Simulation studies show that the bias of our proposed interval‐censored RMST estimator is negligible and the testing procedure delivers promising performance in detecting between‐group difference with regard to size and power under various configurations of survival curves. The proposed method is illustrated by reanalyzing two real datasets containing interval‐censored observations.
Constraining new physics with single top production at LHC
Authors: Stolarski Daniel , Tonero Alberto
Published: August 2020

Abstract

We study effects of beyond the Standard Model physics coupling third generation quarks to leptons of the first two generations. We parametrize these effects by dimension-six effective operators, and we also consider related simplified UV completions: scalar leptoquark and W

t
models. We derive new constraints on these scenarios by using recent ATLAS measurements of differential cross sections of single top production in association with a W boson, and also show how these limits will evolve with future data. We also describe how the limits can be significantly improved by using ratios of differential distributions with different flavours of leptons.
Künstliche Intelligenz in der Plastischen Chirurgie
Authors: Moellhoff N. , Giunta Riccardo E.
Published: August 2020

Hintergrund

Künstliche Intelligenz (KI) ist durch die Instrumentalisierung von Maschinen und Robotik in der Industrie, durch das autonome Fahren und die rasante Entwicklung computerbasierter Systeme längst Bestandteil unseres täglichen Lebens.

Fragestellung

Darstellung aktueller Entwicklungen und Perspektiven von KI in der Plastischen Chirurgie.

Material und Methoden

Auswertung von Statistiken, Evaluation von Originalarbeiten und Übersichtsarbeiten aus Fachzeitschriften.

Ergebnisse

Im Gesundheitswesen und in der Plastischen Chirurgie wird KI im klinischen Alltag im Rahmen der Datenauswertung digitaler Patientenakten oder der Big Data aus zentralen Registern verwendet. 3‑D-Bildgebungssysteme mit intelligenter Software können Operationsergebnisse im Hinblick auf Volumen und Ästhetik beurteilen. Intelligente Roboter unterstützen die mikrochirurgische Anastomosierung immer kleinerer Gefäße und die Implementation von KI im Bereich der Prothetik ermöglicht Patienten eine immer bessere Handfunktion nach Amputationsverletzungen.

Diskussion

Im Sinne der Patienten liegt es in der Verantwortung der experimentellen Chirurgie, die Chancen, Risiken und auch Grenzen von KI-Anwendungen zu erforschen.
Half-Space Stationary Kardar–Parisi–Zhang Equation
Authors: Barraquand Guillaume , Krajenbrink Alexandre , Le Doussal Pierre
Published: August 2020

We study the solution of the Kardar–Parisi–Zhang (KPZ) equation for the stochastic growth of an interface of heighth(x, t) on the positive half line, equivalently the free energy of the continuum directed polymer in a half space with a wall at$$x=0$$x=0. The boundary condition$$\partial _x h(x,t)|_{x=0}=A$$∂xh(x,t)|x=0=Acorresponds to an attractive wall for$$A<0$$A<0, and leads to the binding of the polymer to the wall below the critical value$$A=-1/2$$A=-1/2. Here we choose the initial conditionh(x, 0) to be a Brownian motion in$$x>0$$x>0with drift$$-(B+1/2)$$-(B+1/2). When$$A+B \rightarrow -1$$A+B→-1, the solution is stationary, i.e.$$h(\cdot ,t)$$h(·,t)remains at all times a Brownian motion with the same drift, up to a global height shifth(0, t). We show that the distribution of this height shift is invariant under the exchange of parametersAandB. For any$$A,B > - 1/2$$A,B>-1/2, we provide an exact formula characterizing the distribution ofh(0, t) at any timet, using two methods: the replica Bethe ansatz and a discretization called the log-gamma polymer, for which moment formulae were obtained. We analyze its large time asymptotics for various ranges of parametersA, B. In particular, when$$(A, B) \rightarrow (-1/2, -1/2)$$(A,B)→(-1/2,-1/2), the critical stationary case, the fluctuations of the interface are governed by a universal distribution akin to the Baik–Rains distribution arising in stationary growth on the full-line. It can be expressed in terms of a simple Fredholm determinant, or equivalently in terms of the Painlevé II transcendent. This provides an analog for the KPZ equation, of some of the results recently obtained by Betea–Ferrari–Occelli in the context of stationary half-space last-passage-percolation. From universality, we expect that limiting distributions found in both models can be shown to coincide.
Seismic Risk Assessment of the Railway Network of China’s Mainland
Authors: Zhu Weihua , Liu Kai , Wang Ming , Koks Elco E.
Published: August 2020

Earthquakes pose a great risk to railway systems and services around the world. In China alone, earthquakes caused 88 rail service disruptions between 2012 and 2019. Here, we present a first-of-its-kind methodology to analyze the seismic risk of a railway system using an empirically derived train service fragility curve. We demonstrate our methodology using the Chinese railway system. In doing so, we generate a set of stochastic earthquake scenarios for China based on a national-scale seismicity model. Using disruption records, we construct an empirically grounded fragility curve that relates the failure probability of train services to peak ground acceleration. By combining the simulated earthquakes, the fragility curve, and empirical train flow data from 2016, we quantitatively assess the seismic impact and the risk faced by the Chinese railway system. The maximum train trip loss could reach 2400 trips in response to a single seismic event, accounting for 34% of the national daily train trips. Due to the spatially uneven daily train flow and seismicity distribution, the seismic impact on the railway system in different seismic zones is highly heterogeneous and does not always increase when the hazard intensity increases. More specifically, the results show that the railway lines located in the Qinghai-Tibet and Xinjiang seismic zones exhibit the highest risk. The generated impact curves and the risk map provide a basis for railway planning and risk management decisions.
HIGH-PRECISION BAYESIAN CHRONOLOGICAL MODELING ON A CALIBRATION PLATEAU: THE NIEDERTIEFENBACH GALLERY GRAVE
Authors: Meadows John , Rinne Christoph , Immel Alexander , Fuchs Katharina , Krause-Kyora Ben , Drummer Clara
Published: August 2020

We combine the results of a radiocarbon (14C) dating program with archaeogenetic, osteological and sparse stratigraphic data, to construct a Bayesian chronological model for a multi-generational sequence situated entirely on a plateau in the 14C calibration curve. Calibrated dates of individual human bones from the Late Neolithic gallery grave at Niedertiefenbach, Hesse, Germany, span the entire calibration plateau in the late 4th millennium (ca. 3350–3100/3000 cal BC), but our model restricts the overall period of burial to 3–6 generations centered on the later 3200s, and provides narrower absolute date ranges for specific individuals and associated events. We confirm the accuracy and robustness of this model by sensitivity tests of each of its components. Beyond providing a more dynamic narrative for the formation of the heterogenous burial population at Niedertiefenbach, our results show that calibration plateaus are suitable periods for Bayesian chronological modeling of even relatively brief sequences, provided that all the information employed is correct. Prior information constraining both the order of events, and of potential date differences between them, is essential for the model to give accurate, unimodal estimates of the dates of these events.
ΜΑΝΙΑ AND ΑΛΗΘΕΙΑ IN PLATO'SPHAEDRVS
Authors: Serranito Fábio
Published: August 2020

This article maps the complex and changing interrelation of madness (μανία) and truth (ἀλήθεια) in the erotic speeches of thePhaedrus. I try to show that μανία is not merely a secondary aspect but rather a fundamental element within the structure binding together the sequence of speeches. I will show how what starts as an apparently simple binary opposition between μανία andἀλήθεια in Lysias’ speech and Socrates’ first speech suffers an important modification at the beginning of the palinode, and is finally turned upside down in the radical reappraisal caused by the focus on erotic μανία. The result is a different understanding of μανία, as well as a reassessment of the status and cognitive reliability of day-to-day human perspective.
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

Objective:

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

Legal 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

In 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

The 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

In 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

Humans 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

Earthquake 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

Ultra-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

Recent 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

Many 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

Electrical 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

Most 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

Magnetic 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

Prompt 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

Methionine 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

The 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

Contest 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.
Radial shock waves prevent growth retardation caused by the clinically used drug vismodegib in ex vivo cultured bones
Authors: Ramesh Sowmya , Sävendahl Lars , Madhuri Vrisha , Zaman Farasat
Published: August 2020

In childhood medulloblastoma patients, the hedgehog antagonist vismodegib is an effective anti-cancer treatment but unfortunately induces irreversible growth arrests and growth impairment limiting its use in skeletally immature patients. We hypothesized that radial shock wave treatment (rSWT) may protect drug-induced growth impairment owing to its osteogenic effects. Fetal rat metatarsal bones were exposed to vismodegib (day 0–5; 100 nM) and/or rSWT (single session); other bones from day 1 were continuously exposed to a Gli1 antagonist (GANT61; 10 µM) and/or rSWT (single session). Control bones were untreated. The bone length was measured at intervals; histomorphometric analysis and immunostaining for PCNA, Gli1, and Ihh were performed on the sectioned bones. Bones treated with vismodegib showed impaired bone growth, reduced height of the resting-proliferative zone and reduced hypertrophic cell size compared to control. In vismodegib treated bones, a single session of rSWT partially rescued bone growth, increased the growth velocity, hypertrophic cell size, and restored growth plate morphology. Bones exposed to GANT61 showed impaired bone growth and disorganized growth plate while when combined with rSWT these effects were partially prevented. Locally applied rSWT had a chondroprotective effect in rat metatarsal bones and suggest a novel strategy to prevent growth impairment caused by vismodegib.
Development and validation of a 1-year survival prognosis estimation model for Amyotrophic Lateral Sclerosis using manifold learning algorithm UMAP
Authors: Grollemund Vincent , Chat Gaétan Le , Secchi-Buhour Marie-Sonia , Delbot François , Pradat-Peyre Jean-François , Bede Peter , Pradat Pierre-François
Published: August 2020

Amyotrophic Lateral Sclerosis (ALS) is an inexorably progressive neurodegenerative condition with no effective disease modifying therapies. The development and validation of reliable prognostic models is a recognised research priority. We present a prognostic model for survival in ALS where result uncertainty is taken into account. Patient data were reduced and projected onto a 2D space using Uniform Manifold Approximation and Projection (UMAP), a novel non-linear dimension reduction technique. Information from 5,220 patients was included as development data originating from past clinical trials, and real-world population data as validation data. Predictors included age, gender, region of onset, symptom duration, weight at baseline, functional impairment, and estimated rate of functional loss. UMAP projection of patients shows an informative 2D data distribution. As limited data availability precluded complex model designs, the projection was divided into three zones with relevant survival rates. These rates were defined using confidence bounds: high, intermediate, and low 1-year survival rates at respectively $$90\%$$

90
%

($$\pm 4\%$$

±
4
%

), $$80\%$$

80
%

($$\pm 4\%$$

±
4
%

) and $$58\%$$

58
%

($$\pm 4\%$$

±
4
%

). Predicted 1-year survival was estimated using zone membership. This approach requires a limited set of features, is easily updated, improves with additional patient data, and accounts for results uncertainty.
Fully biological production of adipic acid analogs from branched catechols
Authors: Kruyer Nicholas S. , Wauldron Natalia , Bommarius Andreas S. , Peralta-Yahya Pamela
Published: August 2020

Microbial production of adipic acid from lignin-derived monomers, such as catechol, is a greener alternative to the petrochemical-based process. Here, we produced adipic acid from catechol using catechol 1,2-dioxygenase (CatA) and a muconic acid reductase (MAR) in Escherichia coli. As the reaction progressed, the pH of the media dropped from 7 to 4-5 and the muconic acid isomerized from the cis,cis (ccMA) to the cis,trans (ctMA) isomer. Feeding experiments suggested that cells preferentially uptook ctMA and that MAR efficiently reduced all muconic isomers to adipic acid. Intrigued by the substrate promiscuity of MAR, we probed its utility to produce branched chiral diacids. Using branched catechols likely found in pretreated lignin, we found that while MAR fully reduced 2-methyl-muconic acid to 2-methyl-adipic acid, MAR reduced only one double bond in 3-substituted muconic acids. In the future, MAR’s substrate promiscuity could be leveraged to produce chiral-branched adipic acid analogs to generate branched, nylon-like polymers with reduced crystallinity.
Structural and functional connectivity from the dorsomedial hypothalamus to the ventral medulla as a chronological amplifier of sympathetic outflow
Authors: Kono Yosuke , Yokota Shigefumi , Fukushi Isato , Arima Yosuke , Onimaru Hiroshi , Okazaki Shuntaro , Takeda Kotaro , Yazawa Itaru , Yoshizawa Masashi , Hasebe Yohei , Koizumi Keiichi , Pokorski Mieczyslaw , Toda Takako , Sugita Kanji , Okada Yasumasa
Published: August 2020

Psychological stress activates the hypothalamus, augments the sympathetic nervous output, and elevates blood pressure via excitation of the ventral medullary cardiovascular regions. However, anatomical and functional connectivity from the hypothalamus to the ventral medullary cardiovascular regions has not been fully elucidated. We investigated this issue by tract-tracing and functional imaging in rats. Retrograde tracing revealed the rostral ventrolateral medulla was innervated by neurons in the ipsilateral dorsomedial hypothalamus (DMH). Anterograde tracing showed DMH neurons projected to the ventral medullary cardiovascular regions with axon terminals in contiguity with tyrosine hydroxylase-immunoreactive neurons. By voltage-sensitive dye imaging, dynamics of ventral medullary activation evoked by electrical stimulation of the DMH were analyzed in the diencephalon-lower brainstem-spinal cord preparation of rats. Although the activation of the ventral medulla induced by single pulse stimulation of the DMH was brief, tetanic stimulation caused activation of the DMH sustained into the post-stimulus phase, resulting in delayed recovery. We suggest that prolonged excitation of the DMH, which is triggered by tetanic electrical stimulation and could also be triggered by psychological stress in a real life, induces further prolonged excitation of the medullary cardiovascular networks, and could contribute to the pathological elevation of blood pressure. The connectivity from the DMH to the medullary cardiovascular networks serves as a chronological amplifier of stress-induced sympathetic excitation. This notion will be the anatomical and pathophysiological basis to understand the mechanisms of stress-induced sustained augmentation of sympathetic activity.
Association of change in alcohol consumption with cardiovascular disease and mortality among initial nondrinkers
Authors: Chang Jun Young , Choi Seulggie , Park Sang Min
Published: August 2020

There is a paucity of studies on the influence of alcohol intake among non-drinkers. We evaluated the association between an increase in alcohol consumption and primary prevention of major adverse cardiovascular events (MACE) among non-drinkers. Data collected by the National Health Insurance Service in the Korea between 2007 and 2013 were analysed. A total of 112,403 subjects were included and followed up from 1 January 2011 to 31 December 2013. Increases in alcohol consumption, measured as glasses per day, at the second medical check-up, were categorized into maintenance of nondrinking (0), > 0– ≤ 1, > 1– ≤ 2, > 2– ≤ 4, and > 4. Hazard ratios (HRs) for MACE and all-cause mortality on increase in alcohol consumption were calculated. Compared to that in non-drinkers at the second check-up, the risk of MACE significantly decreased among the subjects with an increase in alcohol consumption to ≤ 1 glass per day (HR 0.79, 95% CI 0.68–0.92). However, a light increase in alcohol consumption did not reduce the risk of stroke or all-cause mortality (stroke, HR 0.83, 95% CI 0.68–1.02; all-cause mortality, HR 0.89, 95% CI 0.73–1.09). Compared to continual non-drinkers, those who drank > 2 glass per day had higher risk for death due to external causes (aHR 2.06, 95% CI 1.09–3.90). The beneficial effect of light increments in alcohol consumption on the occurrence of MACE may have resulted from the inappropriate inclusion of sick quitters, who maintained a nondrinking status, in the reference group.