bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation metrics and dimensional reduction for binary classification algorithms: a case study on bankruptcy prediction
Authors: Pérez-Pons María E. , Parra-Dominguez Javier , Hernández Guillermo , Herrera-Viedma Enrique , Corchado Juan M.
Published: January 2022

This paper presents a methodology that permits to automate binary classification using the minimum possible number of attributes. In this methodology, the success of the binary prediction does not lie in the accuracy of an algorithm but in the evaluation metrics, which give information about the goodness of fit; which is an important factor when the data batch is unbalanced. The proposed methodology assesses the possible biases in identifying one algorithm as the best performer when considering the goodness of fit of an algorithm through evaluation metrics. The dimension of data has been reduced through the cumulative explained variance. Then, the performance of six machine learning classification models has been compared through Matthew correlation coefficient (MCC), area under curve – receiver operating characteristic (ROC-AUC), and area under curve – precision-recall (AUC-PR). The results show graphically and numerically how the evaluation metrics interfere with the most optimal outcome of an algorithm. The algorithms with the best performance in terms of evaluation metrics have been random forest and gradient boosting. In the imbalanced datasets, MCC has provided better prediction results than ROC-AUC or AUC-PR. The proposed methodology is adapted to the case of bankruptcy prediction.
The generalized join the shortest orbit queue system: stability, exact tail asymptotics and stationary approximations
Authors: Dimitriou Ioannis
Published: January 2022

We introduce the generalized join the shortest queue model with retrials and two infinite capacity orbit queues. Three independent Poisson streams of jobs, namely a smart, and two dedicated streams, flow into a single-server system, which can hold at most one job. Arriving jobs that find the server occupied are routed to the orbits as follows: Blocked jobs from the smart stream are routed to the shortest orbit queue, and in case of a tie, they choose an orbit randomly. Blocked jobs from the dedicated streams are routed directly to their orbits. Orbiting jobs retry to connect with the server at different retrial rates, i.e., heterogeneous orbit queues. Applications of such a system are found in the modeling of wireless cooperative networks. We are interested in the asymptotic behavior of the stationary distribution of this model, provided that the system is stable. More precisely, we investigate the conditions under which the tail asymptotic of the minimum orbit queue length is exactly geometric. Moreover, we apply a heuristic asymptotic approach to obtain approximations of the steady-state joint orbit queue-length distribution. Useful numerical examples are presented and shown that the results obtained through the asymptotic analysis and the heuristic approach are agreed.
Phase evolution studies of mechanochemical-prepared Cu2ZnSnS4powder via comprehensive annealing and milling investigation
Authors: Alee Soheil , Asemi Morteza , Soltanmohammadi Mina , Ghanaatshoar Majid
Published: January 2022

Environmental benign and stable kesterite Cu2ZnSnS4(CZTS) photovoltaics provides an intriguing alternative to conventional solar cells. However, further development is required for boosting theVoc-deficit in CZTS photovoltaic to enhance the cell function. Intending to obtain high-quality CZTS powder as the basis, here we report a comprehensive study of the vacuum annealing process (including annealing temperature, duration, and heating rates) for synthesized powder with the ball-milling method, which leads to a high-quality kesterite structure. According to analysis outcomes, there are not any significant differences in structures of differently milled specimens while the optical and morphological findings exhibit distinctive results. In short, the 10 h milled powder annealed at 500 °C for 5 h with a 9 °C min−1heating rate possesses a high-quality structure alongside the desired 1.53 eV bandgap and optimum morphological characteristics.
Authorship attribution using author profiling classifiers
Authors: Deutsch Caio , Paraboni Ivandré
Published: January 2022

Authorship attribution – the computational task of identifying the author of a given text document within a set of possible candidates – has been attracting interest in Natural Language Processing research for many years. At the same time, significant advances have also been observed in the related field of author profiling, that is, the computational task of learning author demographics from text such as gender, age and others. The close relation between the two topics – both of which focused on gaining knowledge about the individual who wrote a piece of text – suggests that research in these fields may benefit from each other. To illustrate this, this work addresses the issue of author identification with the aid of author profiling methods, adding demographics predictions to an authorship attribution architecture that may be particularly suitable to extensions of this kind, namely, a stack of classifiers devoted to different aspects of the input text (words, characters and text distortion patterns.) The enriched model is evaluated across a range of text domains, languages and author profiling estimators, and its results are shown to compare favourably to those obtained by a standard authorship attribution method that does not have access to author demographics predictions.
Diversity and genetic structure ofAstronium concinnumSchott ex Spreng. in conservation units
Authors: Vieira Alessandra Abreu Rodrigues , de Souza Lucimara Cruz , da Silva Júnior Adelson Lemes , Alves Bruno Quinelato , de Miranda Fábio Demolinari , Moreira Sarah Ola , Caldeira Marcos Vinicius Winckler
Published: January 2022

Astronium concinnumSchott ex Spreng. (Anacardiaceae) is a species used in civil construction, naval, luxury furniture, in addition to the potential for recovery and restoration of habitats. The objective of this work was to characterize the diversity and genetic structure of theA. concinnumin the Conservation Units, National Forest of Pacotuba and Private Natural Heritage Reserve of Cafundó, located in the south of the state of Espírito Santo. Eight ISSR primers were used, which produced 121 DNA fragments and 73.55% polymorphism. In the analysis of genetic dissimilarity, seven distinct groups were identified, with the majority of individuals (from both Conservation Units) being brought together into a single group. The genetic diversity of Nei (H*) and the Shannon index (I*), provided values for the species of 0.312 and 0.473, respectively, indicating the genetic diversity conserved in the species and its potential use for collecting genetically diversified seeds. The analysis of molecular variance revealed that most of the diversity (92.54%) is distributed within populations and the value of gene flow (Nm= 10.629) indicates the high rate of genetic exchange between Conservation Units. The results of the genetic structuring indicated the division of individuals into three genetic groups (K= 3), however, it was possible to observe a mixture of genetic material with the sharing of alleles between the three groups. The results indicate thatA. concinnumtrees maintain genetic diversity for their maintenance. In addition, the potential of the analysed individuals was certified as future matrixes for seed collection.
Was motiviert Schülerinnen und Schüler für das Lehramt?
Authors: Renger Sophus , Köller Michaela M. , Möller Jens
Published: January 2022

Zusammenfassung. Lehramtsstudierende mit ausgeprägten intrinsischen Berufswahlmotivationen zeigen eine höhere Studienzufriedenheit und bessere Studienleistungen. In der bisherigen Forschung zu lehramtsspezifischer Berufswahl werden zwei Fragen nicht beantwortet, die für die Rekrutierung zukünftiger Lehramtsstudierender relevant sind: Erstens ist – ohne die Verwendung einer Kontrollgruppe oder einer Stichprobe vor Studienwahl – nicht klar, ob die erfassten Berufswahlmotivationen für die lehramtsspezifische Berufswahl von Schülerinnen und Schülern relevant sind. Zweitens existiert kein Instrument, mit dem lehramtsspezifische Berufswahlmotivationen bei Schülerinnen und Schülern erhoben werden können. Daher wurde mit dem Fragebogen zur Erfassung der Motivation für die Wahl des Lehramtsstudiums (FEMOLA; Pohlmann & Möller, 2010 ) ein im deutschsprachigen Raum etabliertes Instrument adaptiert und in drei Stichproben an N = 215, N = 278 und N = 350 Schülerinnen und Schülern einer empirischen Prüfung unterzogen. Die Struktur des neu entwickelten FEMOLA-S bildet Komponenten der intrinsischen (Pädagogisches Interesse und Interesse an Wissensvermittlung) und extrinsischen Berufswahlmotivationen (Soziale Einflüsse, Nützlichkeit, Geringe Schwierigkeit des Studiums) ab, die eine gute Passung zu den erhobenen Daten zeigen. Die intrinsische Berufswahlmotivation erlaubte im Gegensatz zur extrinsischen eine Vorhersage der lehramtsspezifischen Berufswahlintention von Schülerinnen und Schülern, auch über die in der Berufswahlforschung häufig verwendeten beruflichen Interessenstypen nach Holland (1997) hinaus. Mögliche Anwendungsfelder des entwickelten Fragebogens und die Implikationen der Ergebnisse für die Gewinnung von geeigneten Lehramtsstudierenden werden diskutiert.
Assessment of Satellite Precipitation Products in Relation With Orographic Enhancement Over the Western United States
Authors: Adhikari Abishek , Behrangi Ali
Published: January 2022

Two years (2018–2019) of different precipitation products are assessed for their skill in capturing orographic precipitation over the western United States (30°–50°N & 105°–135°W) using two popular methods. The first method defines orographic indices using orographic enhancement and moisture content that represents the amount of moisture advected over sloping terrain. In contrast, the second method classifies precipitation events into orographic and non‐orographic events. NCEP Stage‐IV product is used as a reference. All of the evaluated products (radar, microwave imager/sounder, and infrared) show more significant errors for the orographic than the non‐orographic events. The Global Precipitation Mission (GPM) products; Dual‐frequency Precipitation Radar (DPR), combined radar and radiometer (COMBINE), and GPM Microwave Imager (GMI), and Microwave Humidity Sounder (MHS), severely underestimate the precipitation rates, especially for heavy precipitation (>4 mm/day), whereas infrared precipitation (used in the Integrated Multi‐satellite Retrievals for GPM; IMERG‐IR) and a reanalysis product (ERA5) show relatively better estimation. It was found that the amount of precipitation over the reference (rate BIAS) varies with seasons, so in cold seasons satellite precipitation products tend to underestimate while in warm‐season they (except DPR) tend to overestimate precipitation amount. Most of the satellite products severely underestimate precipitation volume at relatively colder surfaces (<10°C) and lower TPW (<15 mm), but ERA5 shows little rate BIAS in such cases. The underestimation tends to be larger for orographic than non‐orographic events. In contrast, ERA5 shows relatively large underestimation at warmer temperatures (>20°C), where satellite products tend to overestimate precipitation amounts.
Reduced Tropical Cyclone Genesis in the Future as Predicted by a Machine Learning Model
Authors: Qian QiFeng , Jia XiaoJing , Lin Yanluan
Published: January 2022

Due to a lack of observations and limited understanding of the complex mechanisms of tropical cyclone (TC) genesis, the possible TC activity response to future climate change remains controversial. In this work, a machine learning model, called the maximum entropy (MaxEnt) model, is established using various environmental variables. The model performs slightly better than the genesis potential index for historical TC activities based on the spatial correlation coefficient. Using coupled model intercomparison project phase 6 model projections, the MaxEnt model predicts a statistically significant decreasing trend of TC genesis probability under all shared socioeconomic pathway scenarios. In addition, our analysis reveals that TC genesis might have a complex nonlinear relationship with potential intensity, which is different from the positive relationship reported in previous studies and might be the key factor leading to the model predicting reduced TC genesis in the future.
Biogeochemical Dynamics in Adjacent Mesoscale Eddies of Opposite Polarity
Authors: Barone Benedetto , Church Matthew J. , Dugenne Mathilde , Hawco Nicholas J. , Jahn Oliver , White Angelicque E. , John Seth G. , Follows Michael J. , DeLong Edward F. , Karl David M.
Published: January 2022

We examined the biogeochemical impact of paired mesoscale cyclones and anticyclones in spatial proximity (<200 km apart) in the North Pacific Subtropical Gyre. While previous studies have demonstrated that upwelling associated with the intensification of cyclonic eddies can supply nutrients supporting plankton productivity, we observed that steeper vertical gradients in inorganic nutrients increased nutrient fluxes due to diapycnal mixing during the mature stage of cyclonic eddies. The increased diapycnal nutrient supply was linked with expansion of eukaryotic phytoplankton biomass and intensification of the deep chlorophyll maximum (DCM) layer. This perturbation in the plankton community was associated with increased fluxes of biominerals (specifically particulate inorganic carbon and particulate silica) and isotopically enriched organic nitrogen in particles exported in the cyclone. The time‐integrated effects of thermocline vertical displacements on the lower euphotic zone were predictable deficits and surpluses of inorganic nutrients and dissolved oxygen, respectively. However, the stoichiometry of oxygen and inorganic nutrients differed from that predicted for production and consumption of phytoplankton biomass, requiring additional biological processes that decouple changes in oxygen and nutrient concentrations. The dynamics revealed by this study may be a common feature of oligotrophic ecosystems, where mesoscale biogeochemical perturbations are buffered by the DCM layer, which limits the ecological impact of eddies in the well‐lit, near‐surface ocean.
HBIs and Sterols in Surface Sediments Across the East Siberian Sea: Implications for Palaeo Sea‐Ice Reconstructions
Authors: Su Liang , Ren Jian , Sicre Marie‐Alexandrine , Bai Youcheng , Jalali Bassem , Li Zhongqiao , Jin Haiyan , Astakhov Anatolii S. , Shi Xuefa , Chen Jianfang
Published: January 2022

Highly branched isoprenoids (HBIs) in marine sediments have emerged as promising semi‐quantitative proxies to reconstruct seasonal sea ice in polar oceans. In this work, we examine the distribution of sympagic HBIs (IP25 and HBI‐II), pelagic phytoplankton biomarkers (brassicasterol, dinosterol and HBI‐III) as well as terrestrial sterols (campesterol and β‐sitosterol) in the surface sediments of the East Siberian Sea (ESS) to test their reliability as sea‐ice proxies under continental run‐off influence. Our data suggest that dinosterol performs better than brassicasterol to assess sea ice across the ESS shelf, yet the correlation between PDIP25 and spring sea ice is relatively weak but improves when removing sites with salinity <25. Strongest relationship is found between PIIIIP25 and summer sea ice in regions remote from riverine influence. Overall, our results show that semi‐quantitative estimates of sea ice based on biomarkers can be problematic in Arctic Ocean margins because of biases induced by continental run‐off on biological productivity and sea‐ice production.
Dusty Mafic Rocks Along the Path of Chang'E‐4 Rover: Initial Analysis of the Image Cubes of the Onboard Visible and Near‐Infrared Imaging Spectrometer
Authors: Wang Xing , Liu Jianjun , Liu Dawei , Huang Hai , Guo Lin , Zhang Qing , Chen Yuan , Liu Bin , Chen Wangli , Ren Xin , Li Chunlai
Published: January 2022

The Yutu‐2 rover of Chang'E‐4 encountered four special rocks along its path. The onboard Visible and Near‐infrared Imaging Spectrometer (VNIS) collected their spectral data at close range. In this work, we focus on the visible/near‐infrared image cubes captured by the VNIS. Simple classification was performed using the K‐means algorithm based on the 750/900 nm spectral ratios to highlight the surface material variations. In the case of narrow measurements of phase angle, the classification results were not significantly affected by viewing geometry. Varying degrees of dust coverage on the rock surfaces were revealed, which may be attributed to ejecta deposition and dust electrostatic levitation. The spectral shapes of the less dust‐covered surfaces indicated that these rocks are dominated by mafic materials, suggesting they may not originate from the lunar upper crust. The influence of dust coverage on spectral measurement of rocks was also confirmed, which significantly attenuates the absorption depths.
Hydroclimate and ENSO Variability Recorded by Oxygen Isotopes From Tree Rings in the South American Altiplano
Authors: Rodriguez‐Caton Milagros , Andreu‐Hayles Laia , Daux Valérie , Vuille Mathias , Varuolo‐Clarke Arianna M. , Oelkers Rose , Christie Duncan A. , D’Arrigo Rosanne , Morales Mariano S. , Palat Rao Mukund , Srur Ana M. , Vimeux Françoise , Villalba Ricardo
Published: January 2022

Hydroclimate variability in tropical South America is strongly regulated by the South American Summer Monsoon (SASM). However, past precipitation changes are poorly constrained due to limited observations and high‐resolution paleoproxies. We found that summer precipitation and the El Niño‐Southern Oscillation (ENSO) variability are well registered in tree‐ring stable oxygen isotopes (δ18OTR) of Polylepis tarapacana in the Chilean and Bolivian Altiplano in the Central Andes (18–22°S, ∼4,500 m a.s.l.) with the northern forests having the strongest climate signal. More enriched δ18OTR values were found at the southern sites likely due to the increasing aridity toward the southwest of the Altiplano. The climate signal of P. tarapacana δ18OTR is the combined result of moisture transported from the Amazon Basin, modulated by the SASM, ENSO, and local evaporation, and emerges as a novel tree‐ring climate proxy for the southern tropical Andes.
Automatic Waterline Extraction and Topographic Mapping of Tidal Flats From SAR Images Based on Deep Learning
Authors: Zhang Shuangshang , Xu Qing , Wang Haoyu , Kang Yanyan , Li Xiaofeng
Published: January 2022

This study presented an intuitive approach to derive large‐scale tidal flat's Digital Elevation Model (DEM). We first developed an automated method for accurately extracting the waterline from Synthetic Aperture Radar images acquired in Subei Sandbanks along the Yellow Sea coast of China between 2015 and 2020 based on deep convolutional neural networks. The statistical results show this method has appreciable accuracy for efficient waterline extraction even under complex imaging conditions with a mean recall and precision of 0.90 and 0.80, respectively. Then the pixel‐level extracted waterlines are calibrated with a global tide model to construct the large‐scale tidal flat's DEM in the study region. The comparison against in situ topographic data shows an error of 29 cm, demonstrating the usefulness of monitoring the morpho‐sedimentary evolution in intertidal areas. Furthermore, the Subei Sandbanks remained stable from 2015 to 2020, while the coastal region changed drastically due to human activities.
Acceleration of Electrons by Whistler‐Mode Hiss Waves at Saturn
Authors: Woodfield E. E. , Glauert S. A. , Menietti J. D. , Horne R. B. , Kavanagh A. J. , Shprits Y. Y.
Published: January 2022

Plasmaspheric hiss waves at the Earth are well known for causing losses of electrons from the radiation belts through wave particle interactions. At Saturn, however, we show that the different plasma density environment leads to acceleration of the electrons rather than loss. The ratio of plasma frequency to electron gyrofrequency frequently falls below one creating conditions for hiss to accelerate electrons. The location of hiss at high latitudes (>25°) coincides very well with this region of very low density. The interaction between electrons and hiss only occurs at these higher latitudes, therefore the acceleration is limited to mid to low pitch angles leading to butterfly pitch angle distributions. The hiss is typically an order of magnitude stronger than chorus at Saturn and the resulting acceleration is rapid, approaching steady state in one day at 0.4 MeV at L = 7 and the effect is stronger with increasing L‐shell.
Impacts of the Unforced Pattern Effect on the Cloud Feedback in CERES Observations and Climate Models
Authors: Chao Li‐Wei , Muller Jacob C. , Dessler Andrew E.
Published: January 2022

The equilibrium climate sensitivity estimated from different sources is inconsistent due to its dependence on the surface warming pattern. Cloud feedbacks have been identified as the major contributor to this so‐called pattern effect. We find a large unforced pattern effect in CERES data, with cloud feedback estimated from two consecutive 125‐month periods (March 2000–July 2010 and August 2010–December 2020) changing from −0.45 ± 0.85 to +1.2 ± 0.78 W/m2/K. When comparing to models, 27% of consecutive 10‐year segments in CMIP6 control runs have differences similar to the observations. We also compare the spatial patterns in the CERES data to those in climate models and find they are similar, with the East Pacific playing a key role. This suggests that the impact of the unforced pattern effect can be significant and that models are capable of reproducing its global‐average magnitude.
Convective and Microphysical Characteristics of Extreme Precipitation Revealed by Multisource Observations Over the Pearl River Delta at Monsoon Coast
Authors: Yu Shuting , Luo Yali , Wu Chong , Zheng Dong , Liu Xiantong , Xu Weixin
Published: January 2022

Extreme precipitation is an issue of worldwide concern, but its microphysics remain elusive. The convective and microphysical characteristics of extreme precipitation features (EPFs) in a monsoon coastal area (South China) are investigated mainly using 2‐year observations from a dual‐polarization radar and distrometers. The EPFs are accompanied by a broad range of convective intensity, and categorized into the “intense”, “moderate”, and “weak” convection accounting for 17.3%, 48.6% and 34.1% of the total population, respectively. The EPFs with weaker convection show weakened size sorting and less breakup of large raindrops, but a larger ratio of liquid water path to ice water path and more prominent coalescence warm‐rain process. All the three categories are dominated by the coalescence in the liquid‐phase processes, and have much more populous raindrops than the “continental” with a mean size larger than the “maritime” regime. These results improve our understanding of extreme precipitation from the microphysical perspective.
Crustal Structure of the Incoming Iquique Ridge Offshore Northern Chile
Authors: Myers E. K. , Roland E. C. , Tréhu A. M. , Davenport K. ,   the PICTURES group
Published: January 2022

The Peru‐Chile subduction zone hosts M > 8 earthquakes as well as multiple ridges on the downgoing Nazca plate, making this region well suited for investigating the formation, evolution, and potential impacts of subducting features on seismogenesis. To evaluate the physical properties and structural variability of the Iquique Ridge offshore northern Chile, we present a P wave velocity model of the Nazca plate and Iquique Ridge outboard of the 2014 M 8.1 Iquique earthquake sequence. 2D tomographic inversions of P wave traveltime data from the 2016 PICTURES (Pisagua/Iquique Crustal Tomography to Understand the Region of the Earthquake Source) controlled‐source experiment indicate that the Iquique Ridge is characterized by significant crustal thickening relative to typical Nazca plate oceanic crust, with a maximum thickness of ∼13 km beneath the most prominent portion of the Iquique Ridge and outer rise. Reduced upper crustal seismic velocities extend from the ridge eastward to the trench, which may indicate increased fracturing and/or hydration during plate bending. Corresponding multi‐channel seismic reflection data show along‐profile structural variation as well, including an intermittent Moho reflector near the onset of crustal thickening and faulting along the landward slope. The structural heterogeneity entering the Peru‐Chile Trench has potential implications for slip behavior at depth assuming that the anomalous crustal structure continues beneath the forearc. We suggest that the increased buoyant normal force associated with discrete subducted Iquique Ridge seamounts similar to the zone of thick crust imaged here could lead to localized increased interplate coupling, while entrained sediment and fractured/altered crust could facilitate aseismic slip.
Supraglacial Drainage Efficiency of the Greenland Ice Sheet Estimated From Remote Sensing and Climate Models
Authors: Yang Kang , Smith Laurence C. , Andrews Lauren C. , Fettweis Xavier , Li Manchun
Published: January 2022

Supraglacial stream/river catchments drain large volumes of surface meltwater off the southwestern Greenland Ice Sheet surface. Previous studies note a strong seasonal evolution of their drainage density (Dd), a classic measure of drainage efficiency defined as open channel length per unit catchment area, but a direct correlation between Dd and surface meltwater runoff (R) has not been established. We use 27 high‐resolution (∼0.5 m) satellite images to map seasonally evolving Dd for four GrIS supraglacial catchments, with elevations ranging from 1,100 m to 1,700 m. We find a positive linear correlation (r2 = 0.70, p < 0.01) between Dd and simulations of runoff production from two climate models (MAR v3.11 and MERRA‐2). Applying this R‐Dd empirical relationship to climate model output enables parameterization of spatial and temporal changes in supraglacial drainage efficiency continuously throughout the melt season, although temporal and spatial skewness of Dd observations likely affects the application of this R‐Dd relationship on crevasse fields and snow/firn surfaces. Incorporating this information into a simple surface routing model finds that high runoff leads to earlier, larger diurnal peaks of runoff transport on the ice surface, owing to increased Dd. This effect progressively declines from low (∼1,100 m) to high (∼1,700 m) elevation, causing a roughly order‐of‐magnitude reduction in diurnal runoff variability at the highest elevations relative to standard climate model output. Combining intermittent satellite Dd mapping with climate model output thus promises to improve characterization of supraglacial drainage efficiency to the benefit of supraglacial meltwater routing and subglacial hydrology models.
Evaluating Distributed Policies for Conjunctive Surface Water‐Groundwater Management in Large River Basins: Water Uses Versus Hydrological Impacts
Authors: Du Erhu , Tian Yong , Cai Ximing , Zheng Yi , Han Feng , Li Xin , Zhao Mohan , Yang Yi , Zheng Chunmiao
Published: January 2022

It is imperative to understand the interconnectedness of water use and hydrological impacts for water policy design underlying varying hydrological conditions across space and over time. However, such analysis remains difficult, constrained by the lack of appropriate modeling tools that fully integrate water policies, water use, and hydrological processes with high spatiotemporal resolutions. To address this challenge, this study proposes a distributed policy design scheme featuring spatially variable and temporally dynamic policies for conjunctive surface water‐groundwater management in large river basins. A fully integrated modeling framework is developed to tightly couple (a) an agent‐based model for farmers' water use under distributed water policies and (b) a physically based hydrological model for surface water‐groundwater processes. The modeling framework is applied to the Heihe River Basin to assess water use and hydrological impacts under distributed water policies. By using the distributed policy scheme to adjust a water policy (e.g., groundwater tax) across space and over time, we found that hydrological outcomes can be improved without adversely reducing agricultural water supply. For example, by shifting the implementation of a high groundwater tax from dry to wet years, a rise of the water table by 0.28 m (0.03–0.95 m across different irrigation districts) can be achieved while the total water supply is maintained at a similar level. Furthermore, hydrological externality effects among nearby districts can be explicitly identified and quantified based on assessments of spatially varying water policies. This study highlights the need for water policy design to consider spatiotemporal variations in the physical hydrological system.
Self-directed online machine learning for topology optimization
Authors: Deng Changyu , Wang Yizhou , Qin Can , Fu Yun , Lu Wei
Published: January 2022

Topology optimization by optimally distributing materials in a given domain requires non-gradient optimizers to solve highly complicated problems. However, with hundreds of design variables or more involved, solving such problems would require millions of Finite Element Method (FEM) calculations whose computational cost is huge and impractical. Here we report Self-directed Online Learning Optimization (SOLO) which integrates Deep Neural Network (DNN) with FEM calculations. A DNN learns and substitutes the objective as a function of design variables. A small number of training data is generated dynamically based on the DNN’s prediction of the optimum. The DNN adapts to the new training data and gives better prediction in the region of interest until convergence. The optimum predicted by the DNN is proved to converge to the true global optimum through iterations. Our algorithm was tested by four types of problems including compliance minimization, fluid-structure optimization, heat transfer enhancement and truss optimization. It reduced the computational time by 2 ~ 5 orders of magnitude compared with directly using heuristic methods, and outperformed all state-of-the-art algorithms tested in our experiments. This approach enables solving large multi-dimensional optimization problems.
A Kerr polarization controller
Authors: Moroney N. , Del Bino L. , Zhang S. , Woodley M. T. M. , Hill L. , Wildi T. , Wittwer V. J. , Südmeyer T. , Oppo G.-L. , Vanner M. R. , Brasch V. , Herr T. , Del’Haye P.
Published: January 2022

Kerr-effect-induced changes of the polarization state of light are well known in pulsed laser systems. An example is nonlinear polarization rotation, which is critical to the operation of many types of mode-locked lasers. Here, we demonstrate that the Kerr effect in a high-finesse Fabry-Pérot resonator can be utilized to control the polarization of a continuous wave laser. It is shown that a linearly-polarized input field is converted into a left- or right-circularly-polarized field, controlled via the optical power. The observations are explained by Kerr-nonlinearity induced symmetry breaking, which splits the resonance frequencies of degenerate modes with opposite polarization handedness in an otherwise symmetric resonator. The all-optical polarization control is demonstrated at threshold powers down to 7 mW. The physical principle of such Kerr effect-based polarization controllers is generic to high-Q Kerr-nonlinear resonators and could also be implemented in photonic integrated circuits. Beyond polarization control, the spontaneous symmetry breaking of polarization states could be used for polarization filters or highly sensitive polarization sensors when operating close to the symmetry-breaking point.
Merging enzymes with chemocatalysis for amide bond synthesis
Authors: Bering Luis , Craven Elliott J. , Sowerby Thomas Stanley A. , Shepherd Sarah A. , Micklefield Jason
Published: January 2022

Amides are one of the most fundamental chemical bonds in nature. In addition to proteins and other metabolites, many valuable synthetic products comprise amide bonds. Despite this, there is a need for more sustainable amide synthesis. Herein, we report an integrated next generation multi-catalytic system, merging nitrile hydratase enzymes with a Cu-catalysed N-arylation reaction in a single reaction vessel, for the construction of ubiquitous amide bonds. This synergistic one-pot combination of chemo- and biocatalysis provides an amide bond disconnection to precursors, that are orthogonal to those in classical amide synthesis, obviating the need for protecting groups and delivering amides in a manner unachievable using existing catalytic regimes. Our integrated approach also affords broad scope, very high (molar) substrate loading, and has excellent functional group tolerance, telescoping routes to natural product derivatives, drug molecules, and challenging chiral amides under environmentally friendly conditions at scale.
Ionic covalent organic framework based electrolyte for fast-response ultra-low voltage electrochemical actuators
Authors: Yu Fei , Ciou Jing-Hao , Chen Shaohua , Poh Wei Church , Chen Jian , Chen Juntong , Haruethai Kongcharoen , Lv Jian , Gao Dace , Lee Pooi See
Published: January 2022

Electrically activated soft actuators with large deformability are important for soft robotics but enhancing durability and efficiency of electrochemical actuators is challenging. Herein, we demonstrate that the actuation performance of an ionic two-dimensional covalent-organic framework based electrochemical actuator is improved through the ordered pore structure of opening up efficient ion transport routes. Specifically, the actuator shows a large peak to peak displacement (9.3 mm, ±0.5 V, 1 Hz), a fast-response time to reach equilibrium-bending (~1 s), a correspondingly high bending strain difference (0.38%), a broad response frequency (0.1–20 Hz) and excellent durability (>99%) after 23,000 cycles. The present study ascertains the functionality of soft electrolyte as bionic artificial actuators while providing ideas for expanding the limits in applications for robots.
Modulus adaptive lubricating prototype inspired by instant muscle hardening mechanism of catfish skin
Authors: Zhang Yunlei , Zhao Weiyi , Ma Shuanhong , Liu Hui , Wang Xingwei , Zhao Xiaoduo , Yu Bo , Cai Meirong , Zhou Feng
Published: January 2022

In nature, living organisms evolve unique functional components with mechanically adaptive compatibility to cater dynamic change of interface friction/lubrication. This mechanism can be used for developing intelligent artificial lubrication-regulation systems. Inspired by the muscle hardening-triggered lubrication oflongsnout catfish, here we report a modulus adaptive lubricating hydrogel prototype consisting of top mucus-like hydrophilic lubricating layer and muscle-like bottom hydrogel that can stiffen via thermal-triggered phase separation. It exhibits instant switch from soft/high frictional state (~0.3 MPa,μ~0.37) to stiff/lubricating state (~120 MPa,μ~0.027) in water upon heating up. Such switchable lubrication is effective for wide range of normal loads and attributed to the modulus-dominated adaptive contact mechanism. As a proof-of-concept, switchable lubricating hydrogel bullets and patches are engineered for realizing controllable interface movements. These important results demonstrate potential applications in the fields of intelligent motion devices and soft robots.
The mitochondrial β-oxidation enzyme HADHA restrains hepatic glucagon response by promoting β-hydroxybutyrate production
Authors: Pan An , Sun Xiao-Meng , Huang Feng-Qing , Liu Jin-Feng , Cai Yuan-Yuan , Wu Xin , Alolga Raphael N. , Li Ping , Liu Bao-Lin , Liu Qun , Qi Lian-Wen
Published: January 2022

Disordered hepatic glucagon response contributes to hyperglycemia in diabetes. The regulators involved in glucagon response are less understood. This work aims to investigate the roles of mitochondrial β-oxidation enzyme HADHA and its downstream ketone bodies in hepatic glucagon response. Here we show that glucagon challenge impairs expression of HADHA. Liver-specific HADHA overexpression reversed hepatic gluconeogenesis in mice, while HADHA knockdown augmented glucagon response. Stable isotope tracing shows that HADHA promotes ketone body production via β-oxidation. The ketone body β-hydroxybutyrate (BHB) but not acetoacetate suppresses gluconeogenesis by selectively inhibiting HDAC7 activity via interaction with Glu543 site to facilitate FOXO1 nuclear exclusion. In HFD-fed mice, HADHA overexpression improved metabolic disorders, and these effects are abrogated by knockdown of BHB-producing enzyme. In conclusion, BHB is responsible for the inhibitory effect of HADHA on hepatic glucagon response, suggesting that HADHA activation or BHB elevation by pharmacological intervention hold promise in treating diabetes.
Upcycling of dynamic thiourea thermoset polymers by intrinsic chemical strengthening
Authors: Feng Haijun , Zheng Ning , Peng Wenjun , Ni Chujun , Song Huijie , Zhao Qian , Xie Tao
Published: January 2022

Thermoset polymers are indispensable but their environmental impact has been an ever-increasing concern given their typical intractability. Although concepts enabling their reprocessing have been demonstrated, their practical potential is limited by the deteriorated performance of the reprocessed materials. Here, we report a thiourea based thermoset elastomer that can be reprocessed with enhanced mechanical properties. We reveal that the thiourea bonds are dynamic which leads to the reprocessibility. More importantly, they can undergo selective oxidation during high temperature reprocessing, resulting in significant chemical strengthening within certain reprocessing cycles. This is opposite to most polymers for which reprocessing typically results in material deterioration. The possibility of having materials with inherent reprocessing induced performance enhancement points to a promising direction towards polymer recycling.
Automated pipeline for superalloy data by text mining
Authors: Wang Weiren , Jiang Xue , Tian Shaohan , Liu Pei , Dang Depeng , Su Yanjing , Lookman Turab , Xie Jianxin
Published: January 2022

Data provides a foundation for machine learning, which has accelerated data-driven materials design. The scientific literature contains a large amount of high-quality, reliable data, and automatically extracting data from the literature continues to be a challenge. We propose a natural language processing pipeline to capture both chemical composition and property data that allows analysis and prediction of superalloys. Within 3 h, 2531 records with both composition and property are extracted from 14,425 articles, coveringγ′ solvus temperature, density, solidus, and liquidus temperatures. A data-driven model forγ′ solvus temperature is built to predict unexplored Co-based superalloys with highγ′ solvus temperatures within a relative error of 0.81%. We test the predictions via synthesis and characterization of three alloys. A web-based toolkit as an online open-source platform is provided and expected to serve as the basis for a general method to search for targeted materials using data extracted from the literature.
A common variant in 11q23.3 associated with hyperlipidemia is mediated by the binding and regulation of GATA4
Authors: Chou Wen-Cheng , Chen Wei-Ting , Shen Chen-Yang
Published: January 2022

Large-scale genome-wide associations comprising multiple studies have identified hundreds of genetic loci commonly associated with hyperlipidemia-related phenotypes. However, single large cohort remains necessary in aiming to investigate ethnicity-specific genetic risks and mechanical insights. A community-based cohort comprising 23,988 samples that included both genotype and biochemical information was assembled for the genome-wide association analysis (GWAS) of hyperlipidemia. The analysis identified fifty genetic variants (P < 5 × 10−8) on five different chromosomes, and a subsequent validation analysis confirmed the significance of the lead variants. Integrated analysis combined with cell-based experiments of the most statistically significant locus in 11q23.3 revealed rs651821 (P = 4.52 × 10−76) as the functional variant. We showed transcription factor GATA4 preferentially binds the T allele of rs651821, the protective allele for hyperlipidemia, which promoted APOA5 expression in liver cells and individuals with the TT genotype of rs651821. As GATA4-APOA5 axis maintains triglyceride homeostasis, GATA4 activation by phenylephrine implies synergism for lowering triglyceride levels in hyperlipidemia patients. Our study demonstrates that rs651821 mediates APOA5 activation via allele-specific regulation by GATA4. We suggest elevating GATA4 activity could provide a therapeutic potential for treating the development of hyperlipidemia.
Correlation-driven electron-hole asymmetry in graphene field effect devices
Authors: Dale Nicholas , Mori Ryo , Utama M. Iqbal Bakti , Denlinger Jonathan D. , Stansbury Conrad , Fatuzzo Claudia G. , Zhao Sihan , Lee Kyunghoon , Taniguchi Takashi , Watanabe Kenji , Jozwiak Chris , Bostwick Aaron , Rotenberg Eli , Koch Roland J. , Wang Feng , Lanzara Alessandra
Published: January 2022

Electron-hole asymmetry is a fundamental property in solids that can determine the nature of quantum phase transitions and the regime of operation for devices. The observation of electron-hole asymmetry in graphene and recently in twisted graphene and moiré heterostructures has spurred interest into whether it stems from single-particle effects or from correlations, which are core to the emergence of intriguing phases in moiré systems. Here, we report an effective way to access electron-hole asymmetry in 2D materials by directly measuring the quasiparticle self-energy in graphene/Boron Nitride field-effect devices. As the chemical potential moves from the hole to the electron-doped side, we see an increased strength of electronic correlations manifested by an increase in the band velocity and inverse quasiparticle lifetime. These results suggest that electronic correlations intrinsically drive the electron-hole asymmetry in graphene and by leveraging this asymmetry can provide alternative avenues to generate exotic phases in twisted moiré heterostructures.
SUPT4H1-edited stem cell therapy rescues neuronal dysfunction in a mouse model for Huntington’s disease
Authors: Park Hyun Jung , Han Areum , Kim Ji Yeon , Choi Jiwoo , Bae Hee Sook , Cho Gyu-bon , Shin Hyejung , Shin Eun ji , Lee Kang-in , Kim Seokjoong , Lee Jae Young , Song Jihwan
Published: January 2022

Huntington’s disease (HD) is a severe inherited neurological disorder caused by a CAG repeat expansion in the huntingtin gene (HTT), leading to the accumulation of mutant huntingtin with polyglutamine repeats. Despite its severity, there is no cure for this debilitating disease. HTT lowering strategies, including antisense oligonucleotides (ASO) showed promising results very recently. Attempts to develop stem cell-based therapeutics have shown efficacy in preclinical HD models. Using an HD patient’s autologous cells, which have genetic defects, may hamper therapeutic efficacy due to mutant HTT. Pretreating these cells to reduce mutant HTT expression and transcription may improve the transplanted cells’ therapeutic efficacy. To investigate this, we targeted the SUPT4H1 gene that selectively supports the transcription of long trinucleotide repeats. Transplanting SUPT4H1-edited HD-induced pluripotent stem cell-derived neural precursor cells (iPSC-NPCs) into the YAC128 HD transgenic mouse model improved motor function compared to unedited HD iPSC-NPCs. Immunohistochemical analysis revealed reduced mutant HTT expression without compensating wild-type HTT expression. Further, SUPT4H1 editing increased neuronal and decreased reactive astrocyte differentiation in HD iPSC-NPCs compared to the unedited HD iPSC-NPCs. This suggests that ex vivo editing of SUPT4H1 can reduce mutant HTT expression and provide a therapeutic gene editing strategy for autologous stem cell transplantation in HD.
Diffusion kernel-based predictive modeling of KRAS dependency in KRAS wild type cancer cell lines
Authors: Ulmer Bastian , Odenthal Margarete , Buettner Reinhard , Roth Wilfried , Kloth Michael
Published: January 2022

Recent progress in clinical development of KRAS inhibitors has raised interest in predicting the tumor dependency on frequently mutated RAS-pathway oncogenes. However, even without such activating mutations, RAS proteins represent core components in signal integration of several membrane-bound kinases. This raises the question of applications of specific inhibitors independent from the mutational status. Here, we examined CRISPR/RNAi data from over 700 cancer cell lines and identified a subset of cell lines without KRAS gain-of-function mutations (KRASwt) which are dependent on KRAS expression. Combining machine learning-based modeling and whole transcriptome data with prior variable selection through protein-protein interaction network analysis by a diffusion kernel successfully predicted KRAS dependency in the KRASwtsubgroup and in all investigated cancer cell lines. In contrast, modeling by RAS activating events (RAE) or previously published RAS RNA-signatures did not provide reliable results, highlighting the heterogeneous distribution of RAE in KRASwtcell lines and the importance of methodological references for expression signature modeling. Furthermore, we show that predictors of KRASwtmodels contain non-substitutable information signals, indicating a KRAS dependency phenotype in the KRASwtsubgroup. Our data suggest that KRAS dependent cancers harboring KRAS wild type status could be targeted by directed therapeutic approaches. RNA-based machine learning models could help in identifying responsive and non-responsive tumors.
Diagnostic error rates and associated factors for lower gastrointestinal perforation
Authors: Harada Taku , Watari Takashi , Watanuki Satoshi , Hiroshige Juichi , Kushiro Seiko , Miyagami Taiju , Syusa Syunsuke , Suzuki Satoshi , Hiyoshi Tetsuya , Hasegawa Suguru , Nabeshima Shigeki , Aihara Hidetoshi , Yamashita Shun , Tago Masaki , Yoshimura Fumitaka , Kunitomo Kotaro , Tsuji Takahiro , Hirose Masanori , Tsuchida Tomoya , Shimizu Taro
Published: January 2022

Lower gastrointestinal perforation is rare and challenging to diagnose in patients presenting with an acute abdomen. However, no study has examined the frequency and associated factors of diagnostic errors related to lower gastrointestinal perforation. This large-scale multicenter retrospective study investigated the frequency of diagnostic errors and identified the associated factors. Factors at the level of the patient, symptoms, situation, and physician were included in the analysis. Data were collected from nine institutions, between January 1, 2015 and December 31, 2019. Timely diagnosis was defined as diagnosis at the first visit in computed tomography (CT)-capable facilities or referral to an appropriate medical institution immediately following the first visit to a non-CT-capable facility. Cases not meeting this definition were defined as diagnostic errors that resulted in delayed diagnosis. Of the 439 cases of lower gastrointestinal perforation identified, delayed diagnosis occurred in 138 cases (31.4%). Multivariate logistic regression analysis revealed a significant association between examination by a non-generalist and delayed diagnosis. Other factors showing a tendency with delayed diagnosis included presence of fever, absence of abdominal tenderness, and unavailability of urgent radiology reports. Initial misdiagnoses were mainly gastroenteritis, constipation, and small bowel obstruction. In conclusion, diagnostic errors occurred in about one-third of patients with a lower gastrointestinal perforation.