bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Software Methods for Automated Processing of Sources of Personal Origin
Authors: Prigodich Nikita Dmitrievich , Korobko Semen Sergeevich
Published: April 2023

The subject of this research is software methods of automated preprocessing of historical sources and the development of effective solutions to problems when working with sources of personal origin. The article analyzes the current situation in the use of modern software methods. The authors demonstrate the main range of arguments for which such historical sources from a technical point of view should be considered separately. A methodological analysis of the features of the application of optical character recognition based on preprocessed data is carried out. Special attention is paid to the advantages and key parameters of the effectiveness of the final result of work when using automated text processing, including the further use of OCR methods. The scientific novelty of the research lies in the proposal and detailed description of a software solution to the current problem based on machine learning methods. The developed program has three phases of working with digital copies of sources of personal origin. It is based on the use of the OpenCV library and solving a number of problems using the Hough transform. Based on the general analysis of the study, we can highlight the main advantages of automated preprocessing of scanned documents: reducing time, improving accuracy, combating distortion and optimizing the process. The presented results of successful testing of the developed solution allow us to judge the possible areas of its effective application.
Drosophila macrophages control systemic cytokine levels in response to oxidative stress via a non-canonical DNA damage repair signaling cascade
Authors: Hersperger Fabian , Meyring Tim , Weber Pia , Chhatbar Chintan , Monaco Gianni , Classen Anne-Kathrin , Dionne Marc S. , Paeschke Katrin , Prinz Marco , Groß Olaf , Kierdorf Katrin
Published: April 2023

Environmental factors, infection, or injury, cause oxidative stress in diverse tissues, resulting in immune activation and loss of tissue homeostasis. Effective stress response cascades, conserved from invertebrates to mammals, ensure reestablishment of homeostasis and tissue repair. Plasmatocytes, the
Drosophila
macrophage-like cells, are thought to respond to oxidative stress by immune activation, however the signaling cascades involved in oxidative stress sensing and subsequent immune activation are yet to be defined. Furthermore, their role in modulating and controlling oxidative stress response to facilitate tissue repair and survival of the organism is not resolved. Here we describe the responses of hemocytes in adult
Drosophila
to oxidative stress and the essential role of non-canonical DNA damage repair activity in direct “responder” hemocytes to control JNK-mediated stress signaling, systemic levels of the cytokine upd3 and subsequently susceptibility to oxidative stress. Our results point to an essential systemic role of hemocytes in controlling systemic oxidative stress response in
Drosophila
, including energy mobilization for potential tissue repair.
Calcium transients trigger switch-like discharge of prostaglandin E2 (PGE2) in an ERK-dependent manner
Authors: Watabe Tetsuya , Yamahira Shinya , Takakura Kanako , Thumkeo Dean , Narumiya Shuh , Matsuda Michiyuki , Terai Kenta
Published: April 2023

Prostaglandin E2 (PGE2) is a key player in a plethora of physiological and pathological events. Nevertheless, little is known about the dynamics of PGE2 secretion from a single cell and its effect on the neighboring cells. Here, by observing confluent Madin-Darby canine kidney (MDCK) epithelial cells expressing fluorescent biosensors we demonstrate that calcium transients in a single cell cause PGE2-mediated radial spread of PKA activation (RSPA) in neighboring cells. By in vivo imaging, RSPA was also observed in the basal layer of the mouse epidermis. Experiments with an optogenetic tool revealed a switch-like PGE2 discharge in response to the increasing cytoplasmic Ca2+ concentrations. The cell density of MDCK cells correlated with the frequencies of calcium transients and the following RSPA. The ERK MAP kinase activation also enhanced the frequency of RSPA in MDCK and in vivo. Thus, the PGE2 discharge is regulated temporally by calcium transients and ERK activity.
A Pose Estimation Method Combining Instance Segmentation and Point Pair Features
Authors: Xin Yu , Peng Hao
Published: April 2023

For the traditional pose estimation method based on point pair features, both the preprocessing of scene point cloud and the construction of point pair features of scene point cloud have serious time-consuming problems, which cannot meet the needs of actual industry. Therefore, this paper proposes a pose estimation method that combines instance segmentation and point pair features. Therefore, this paper proposes a pose estimation method that combines instance segmentation and point pair features. First, use the Mask R-CNN-based instance segmentation network to obtain the location of the target object in the two-dimensional image of the scene; then, obtain the local point cloud data of the space where the target object is located from this position and the depth information of the scene; finally, the local the point cloud data is used as the scene point cloud based on point pair feature pose estimation to perform feature matching with the point cloud of the target object.
Paisaje de mediación : de parque a un sistema territorial para la mitigación ante desastres : zona de riesgo de tsunami en Pelluhue, patrones remanentes como infraestructuras para la resiliencia
Authors:   ,   Pontificia Universidad Católica de Chile. Escuela de Arquitectura, Briones Cofré Nicolás E.
Published: April 2023

El Parque de Mitigación llega a Chile como una expresión del nuevo paradigma en arquitectura del paisaje que se discute y diseña a nivel mundial; el proyecto como un mediador ante el cambio climático y las “catástrofes naturales”. También hace referencia al rol de conciliador ante las presentes y futuras transformaciones que sufrirán el territorio y el paisaje en los años a por venir (sequías, aumento en el nivel del mar, perdidas de ecologías, entre otras). Los proyectos implementados en Chile –por el MINVU– tras el tsunami que siguió al terremoto de 2010 se destacan siendo representantes de esta nueva línea del paisaje como infraestructura de mitigación. Pero, a una década de la catástrofe, cabe cuestionarse si es que debiera seguir replicándose este modelo, o ser sometido a cambios de fundamento y diseño. De lo anterior propone hacerse cargo esta investigación. Postulando que los casos de parque de mitigación construidos a nivel nacional se concentraron demasiado en sí mismos y en la estandarización de sus intervenciones, descuidando en el diseño la conexión con la escala y los sistemas de paisaje local –que en las zonas de riesgo se caracteriza a priori por sus remanencias y estructuras resilientes. Este estudio está enfocado en el análisis de antecedentes en esta línea de proyectos, así como también en el diseño de un nuevo sistema expandido de mitigación, con arraigo a los patrones preexistentes del sitio y que colabore complementando el trabajo de uno de los parques MINVU ya construidos. El caso de estudio es Pelluhue, localidad costera al sur de la VII Región del Maule, declarada Zona de Riesgo de Tsunami. El sitio se vio gravemente afectado con el maremoto de 2010, en especial por la entrada del oleaje y las inundaciones que se concentraron en el área cercana a la desembocadura del río Curanilahue, que atraviesa por el centro a la zona urbanizada junto al litoral. El proyecto se propone a abordar el rol de mediador entre la zona de riesgo y quienes habitan en ella; insertándose como una continuación de los patrones remanentes, otorgándoles visibilidad y utilizándolos para potenciar la influencia y eficiencia de una intervención local. Su diseño trabaja con las estrategias y operaciones arquitectónicas ya consolidadas de los parques de mitigación, pero bajo esta nueva lectura y proyección del sitio como paisaje de sistemas territoriales para la resiliencia.
El conjunto habitacional como infraestructura adaptable: intervención multiescalar en los colectivos 1010/1020
Authors:   ,   Pontificia Universidad Católica de Chile. Escuela de Arquitectura, Deisen Pavez Sophia
Published: April 2023

A pesar de la alta experiencia en viviendas sociales que se tiene con instituciones como la CORVI y la CORMU, el foco a lo largo de los años no ha dejado de centrarse en la producción masiva y estandarizada de viviendas, sin preocupación en la estructura familiar para la que se construye, ni en la ocupación de los espacios de éstas mismas, lo que ha causado paulatinamente la pérdida del sentido del hogar, provocando la visión de la vivienda como un paquete de atributos no sociales (Jiménez, Hidalgo, Campesino, & Alvarado, 2018). De esta forma, se ha visto quebrantada la manera de interacción con el hogar provocando que la vivienda misma se entienda como una infraestructura en (proceso de) obsolescencia, rígida e inflexible, incapaz de responder a los requerimientos actuales, lo que termina por crear la necesidad de intervenir la vivienda mediante la transformación de los espacios que la componen. Por esto, se requiere pensar y considerar proyectos habitacionales existentes como infraestructura de intervención multiescalar, en donde se planteen espacios integradores que puedan acomodarse a nuestras necesidades, creando viviendas y entornos de calidad, reviviendo la condición de habitabilidad en pos de aumentar la calidad de vida de las personas. Para esto se propone como caso, el estudio de una tipología repetida en Chile, los colectivos 1010/1020 desarrollados por la CORVI, los cuales surgen en la década de los sesenta en una época de gran implementación de bloques habitacionales con el propósito de replicabilidad a futuro, presentando características y cualidades adecuadas para la intervención, como su marco estructural y su buena condición física actual. Bajo ese marco, la premisa fundamental expone que a través de un proceso de reconversión, la vivienda actual transformada y adaptada, se puede adecuar a las necesidades tanto ocupacionales como programáticas posibilitando un proyecto estable y duradero, ayudando así a una integración multiescalar y a la resiliencia de las infraestructuras existentes, reflejándose en un proyecto que contemple mixtura social, programática y la rehabilitación de espacios públicos. Así la investigación busca responder la siguiente pregunta, ¿Cómo se pueden aprovechar y adaptar proyectos habitacionales ya existentes, como los colectivos 1010/1020, para propiciar una integración multiescalar de éstos desde la unidad habitacional hasta su inserción en la ciudad?
Characterizing the Fe K-a line variability in a large sample of AGN
Authors:   ,   Pontificia Universidad Católica de Chile. Instituto de Astrofísica, Andonie Bahamondes Carolina Paz
Published: April 2023

Varios Nucleos Activos de Galaxias (AGN) han mostrado variabilidad en su emisión en rayos X, en particular en el continuo entre 2-10 keV y en la línea de emisión de Hierro en 6.4 keV (Fe K-a). La línea Fe K-a es una característica obicua en el espectro de los AGN y es producida por procesos de reflección entre el continuo y la materia neutra que rodea el Agujero Negro Supermasivo (SMBH) que se encuentra en el centro del AGN. Varios estudios han constreñido la ubicación y el tamaño de las nubes reflectantes en algunos AGN estudiando la reacción de la línea a variaciones del continuo. En estre trabajo, constreñimos la relación entre la línea Fe K-a y el continuo para 19 fuentes, usando datos de los observatorios Chandra y XMM-Newton. Encontramos diferentes comportamientos, los cuales se pueden clasificar en 3 casos. Primero, en algunos AGN el flujo de la línea está dominado por nubes reflectantes ubicadas cerca de la corona de rayos X, como en el disco de acreción o la región de líneas anchas, por lo que la línea reacciona rápido frente a variaciones del continuum en las escalas de tiempo de las observaciones. Para estas fuentes, proporcionamos un límite superior para la región reflectiva. Segundo, en otros casos, la línea Fe K-a reacciona levemente frente a las variaciones del continuo, por lo que los flujos no están correlados, sugiriendo que las nubes reflectantes están localizadas mucho más lejos de la corona, como en el toro polvoriento. El último y tercer caso, son AGN que muestran variabilidad en el continuo y en la línea, pero los flujos no están correlacionados, indicando un escenario más complejo. Encontramos una leve correlación entre la relación Fe K-a-continuo y la masa del SMBH, indicando que a mayores masas las nubes reflectantes estarían ubicadas más cerca de la corona de rayos X. Para complementar los resultados espectrales, analizamos las imágenes de las observaciones de Chandra para ver si la emisión Fe K-a es extendida espacialmente. Encontramos que 14/15 fuentes analizadas son consistentes con una fuente puntual, para las cuales pudimos entregar un límite superior de la región reflectante emitiendo fotones Fe K-a, equivalente a la resolución espacial de Chandra (1.21 hasta 1419 pc).
Propuesta de reglamentación higrotérmica aplicada a la edificación con destino habitacional del Ecuador
Authors:   ,   Pontificia Universidad Católica de Chile. Escuela de Construcción Civil, Pillajo de la Cruz Ernesto Andrés
Published: April 2023

En Ecuador, las estrategias energéticas actuales se alinean al objetivo mundial del desarrollo sostenible. El cambio a una matriz energética basada principalmente en fuentes renovables requiere el uso eficiente de energía en los diversos sectores del país. Bajo este propósito, en el sector residencial, se ha planteado la norma NEC-11 Capítulo 13: Eficiencia energética en la construcción en Ecuador. El presente estudio tiene por objeto aportar a la actual normativa de eficiencia energética a través del desarrollo de la metodología necesaria para la definición de los valores restrictivos de transmitancia térmica de elementos principales de envolvente en edificaciones residenciales. Para esto se revisaron registros meteorológicos y analizó el sector habitacional con el objeto de determinar las características climáticas y constructivas que permitieron pronosticar el comportamiento térmico y desempeño energético de la vivienda predominante en el país. Posteriormente, mediante un análisis energético y económico se eligieron las mejores alternativas de mejoramiento térmico y sus transmitancias. Los resultados obtenidos corresponden a una propuesta de reglamentación higrotérmica destinada a la edificación residencial del Ecuador, que incluye tanto las zonas de aplicación del reglamento como las especificaciones de transmitancia térmica a ser consideradas dentro del diseño de viviendas energéticamente eficientes.
Value of special education in Chile : case study for “Escuelas de Lenguaje”
Authors:   ,   Pontificia Universidad Católica de Chile. Instituto de Economía, Valdivia Cox Sofía
Published: April 2023

This thesis aims to study the strategic positioning of Speech Schools in the Chilean context, using a reform in public policy to study its consequences in the legislative status of Special Schools providers and on the probability of creation of Speech Schools, where we argue that private suppliers behave as profit maximizers. Additionally, it considers an instrumental variable approach to study individual level outcomes from students enrolled in Speech Schools (exclusive education) on academic achievements and overall application set to the regular educational system. Results suggest that prior to the policy change, Speech School suppliers consider the competition in the decision to create a school and maximize the “residual” demand from students in each district. Furthermore, students from Speech Schools are less likely to apply early to the regular system, have lower academic outcomes and are less likely to apply to a Free and High-Medium quality school as a first preference in the centralized admission system. These findings highlight possible perverse incentives that result in excess supply of Special Schools and indicate long-term effects from over diagnosis of students with speech impairment.
Multisensory integration in different states of consciousness
Authors:   ,   Pontificia Universidad Católica de Chile. Facultad de Medicina, Artigas Claudio A.
Published: April 2023

Nuestro mundo es multisensorial. Distintos mecanismos sensoriales operan para poder captar nuestro mundo y otorgarnos una visión coherente y cohesionada de este. Sin embargo, cómo nuestro cerebro logra unir diversos tipos de información por diversos canales es escasamente comprendido. Para entender estos mecanismos, inducimos somnolencia en las personas mientras veían un estímulo audiovisual. Comparando el estado de alerta y de somnolencia, observamos que había dos frecuencias involucradas, Gamma (30 - 48 Hz) y Alpha (8 - 12 Hz). Gamma se encargaba del procesamiento auditivo mientras que Alpha del procesamiento visual, mientras que ambos se manifestaban en la presentación coordinada del estímulo audiovisual. Esto revela que existe una interacción entre estas frecuencias para generar una percepción cohesionada de un estímulo audiovisual.
Precursores del lenguaje escrito en niños de distintos niveles socioeconómicos en Chile
Authors:   ,   Pontificia Universidad Católica de Chile. Escuela de Psicología, Espinoza Velasco María Victoria
Published: April 2023

El objetivo de la presente investigación fue analizar las diferencias existentes en el desarrollo de las habilidades precursoras del lenguaje escrito entre niños de nivel socioeconómico (NSE) alto y bajo, considerando tanto las diferencias existentes al momento de comenzar el proceso de adquisición de la lectura, como aquellas existentes durante el desarrollo de sus trayectorias de aprendizaje. Además, se buscó observar las posibles diferencias respecto del rol predictor de estas habilidades para ambos grupos. El primer estudio analizó las diferencias iniciales existentes en el desarrollo de los distintos precursores de la lectura entre estudiantes de NSE bajo y NSE alto. Los resultados indican la presencia de diferencias significativas favorables al grupo de NSE alto en todos los precursores analizados, existiendo una mayor magnitud de estas respecto del vocabulario y la comprensión oral. Las mayores brechas se pudieron ver en aquellas habilidades relacionadas principalmente con la comprensión y la fluidez lectora, y las brechas de menor magnitud se manifestaron respecto de los precursores relacionados con la decodificación. El segundo estudio se enfocó en analizar las diferencias existentes respecto de las trayectorias de desarrollo de los precursores del lenguaje escrito. Se encontraron diferencias significativas favorables al grupo de nivel socioeconómico alto en el desempeño relativo a todos los precursores evaluados. Sin embargo, las trayectorias de desarrollo de las habilidades fueron similares para conciencia fonológica, conocimiento de las letras, vocabulario y comprensión oral. Solo en el caso de velocidad de denominación se observó una trayectoria compensatoria. El estudio tres se enfoca en el análisis de rol predictor de las diferentes habilidades precursoras, considerando las posibles diferencias existentes entre el impacto que presentan determinadas habilidades sobre la lectura en función del NSE. Los resultados indican que, al considerar los resultados por separado, las habilidades que mejor explican los resultados de lectura son distintas para los niños de NSE alto y NSE bajo. Los resultados ponen de manifiesto la necesidad de implementar estrategias didácticas que permitan a la escuela promover el desarrollo de trayectorias compensatorias respecto de los precursores de la lectura, para posibilitar un acceso más expedito al lenguaje escrito y así disminuir las brechas existentes a nivel de la comprensión lectora y el impacto de estas sobre el desarrollo cognitivo y la adquisición de conocimiento académicos. Finalmente se discute en torno a la urgencia de realizar cambios en el sistema educativo para responder de manera adecuada a las necesidades particulares de distintos grupos de estudiantes. Esto desde una perspectiva orientada hacia la prioridad, que otorgue una educación de mayor calidad a quienes parten desde una situación de desventaja.
Creencias de igualdad en la escuela: evaluación de un programa escolar (ProCiviCo) que promueve comportamientos prosociales y participación ciudadana en adolescentes chilenos
Authors:   ,   Pontificia Universidad Católica de Chile. Escuela de Psicología, Riquelme Peña Andrés Alejandro
Published: April 2023

El proyecto ProCiviCo (Participación Prosocial y Cívica en Contextos Escolares para la Cohesión Social en Chile) es la implementación de un currículum escolar que busca mejorar la cohesión social en el aula en adolescentes chilenos, mediante la promoción de comportamientos prosociales y del compromiso cívico escolar (Luengo Kanacri & Jiménez-Moya, 2017). El presente trabajo estudia el posible efecto que pudo haber tenido esta intervención en el desarrollo de creencias de igualdad en sus participantes. Estas se entienden en esta investigación como adherencia a valores de universalismo y benevolencia (Schwartz & Boehnke, 2004), y a una baja orientación de dominancia social (SDO) (Sidanius & Pratto, 1999). El diseño de la investigación es un randomized control normal trial (Luengo Kanacri et al., 2019), por lo que permite conocer el efecto del programa escolar (ProCiviCo), comparándolo con un grupo control. Se realizan análisis factoriales exploratorios (Lloret-Segura et al., 2014) para evaluar las propiedades psicométricas de estas variables, y se realizan ANCOVAS (Glantz, Slinker & Neilands, 1990) para determinar diferencias significativas entre grupo de control e intervención en las variables ya mencionadas, considerando un post-test (inmediatamente después de terminar la intervención) y un follow-up (a 6 meses de su finalización). Por un lado, se evalúan las propiedades psicométricas de las escalas como adecuadas, a pesar de que las respuestas de los ítems de SDO se ordenan empíricamente distinto a como indica la teoría (Ho, et al., 2015). Por otro lado, no se evidencian diferencias en estas creencias de igualdad entre grupo control y grupo de intervención (ProCiviCo). Se discuten los resultados a la luz de las teorías de base, y se establecen limitaciones del estudio y pasos futuros para la investigación en esta temática.
The impacts airising from the COVID-19 pandemic on supply chains
Authors: Santos Carlos César Ribeiro , Donato Vitório
Published: April 2023

The global COVID-19 pandemic brought about unimaginable consequences for businesses, with lockdown, quarantine and social isolation causing the closure of borders, factories and stores in several countries, which ultimately locked down the most diverse supply chains, demonstrating an important characteristic of society today: supply chains are highly dependent. Business analysts are citing that the effects of the COVID-19 pandemic on supply chains are unprecedented in recent business history, something that can be visualized with supply chains becoming partially paralyzed as a result of official measures to prevent the pandemic from spreading at a speed that health systems cannot meet. However, some academic works have already warned of the danger of business concentration in specific regions of the planet, where the main focus is the low cost of production, without addressing strategic objectives or focusing on strategic products. This work proposes a reflection on the location of suppliers in certain geographical areas, as this implies the use of long supply chains, proposing an alternative for the creation and planning of shorter supply chains for products that are classified as strategic.
Optimizing b‐values schemes for diffusion MRI of the brain with segmented Intravoxel Incoherent Motion (IVIM) model
Authors: Paganelli Chiara , Zampini Marco Andrea , Morelli Letizia , Buizza Giulia , Fontana Giulia , Anemoni Luca , Imparato Sara , Riva Giulia , Iannalfi Alberto , Orlandi Ester , Baroni Guido
Published: April 2023

Purpose

To define an optimal set of b‐values for accurate derivation of diffusion MRI parameters in the brain with segmented Intravoxel Incoherent Motion (IVIM) model.

Methods

Simulations of diffusion signals were performed to define an optimal set of b‐values targeting different perfusion regimes, by relying on an optimization procedure which minimizes the total relative error on estimated IVIM parameters computed with a segmented fitting procedure. Then, the optimal b‐values set was acquired in vivo on healthy subjects and skull base chordoma patients to compare the optimized protocol with a clinical one.

Results

The total relative error on simulations decreased of about 40% when adopting the optimal set of 13 b‐values (0 10 20 40 50 60 200 300 400 1200 1300 1400 1500 s/mm2), showing significant differences and increased precision on D and f estimates with respect to simulations with a non‐optimized b‐values set. Similarly, in vivo acquisitions demonstrated a dependency of IVIM parameters on the b‐values array, with differences between the optimal set of b‐values and a clinical non‐optimized acquisition. IVIM parameters were compatible to literature values, with D (0.679/0.701 [0.022/0.008] ·10−3mm2/s), f (5.49/5.80 [0.70/1.14] %), and D* (8.25/7.67 [0.92/0.83] ·10−3mm2/s) median [interquartile range] estimates for white matter/gray matter in volunteers and D (0.709/0.715/1.06 [0.035/0.023/0.271] ·10−3mm2/s), f (7.08/7.84/21.54 [1.20/1.06/6.05] %), and D* (10.85/11.84/2.32 [1.38/2.32/4.94] ·10−3mm2/s) for white matter/gray matter/Gross Tumor Volume in patients with skull‐base chordoma tumor.

Conclusions

The definition of an optimal b‐values set can improve the estimation of quantitative IVIM parameters. This allows setting up an optimized approach that can be adopted for IVIM studies in the brain.
IMRT QA result prediction via MLC transmission decomposition
Authors: Stasko John T. , Ferris William S. , Adam David P. , Culberson Wesley S. , Frigo Sean P.
Published: April 2023

Background

Quality assurance measurement of IMRT/VMAT treatment plans is resource intensive, and other more efficient methods to achieve the same confidence are desirable.

Purpose

We aimed to analyze treatment plans in the context of the treatment planning systems that created them, in order to predict which ones will fail a standard quality assurance measurement. To do so, we sought to create a tool external to the treatment planning system that could analyze a set of MLC positions and provide information that could be used to calculate various evaluation metrics.

Methods

The tool was created in Python to read in DICOM plan files and determine the beam fluence fraction incident on each of seven different zones, each classified based on the RayStation MLC model. The fractions, termed grid point fractions, were validated by analyzing simple test plans. The average grid point fractions, over all control points for 46 plans were then computed. These values were then compared with gamma analysis pass percentages and median dose differences to determine if any significant correlations existed.

Results

Significant correlation was found between the grid point fraction metrics and median dose differences, but not with gamma analysis pass percentages. Correlations were positive or negative, suggesting differing model parameter value sensitivities, as well as potential insight into the treatment planning system dose model.

Conclusions

By decomposing MLC control points into different transmission zones, it is possible to create a metric that predicts whether the analyzed plan will pass a quality assurance measurement from a dose calculation accuracy standpoint. The tool and metrics developed in this work have potential applications in comparing clinical beam models or identifying their weak points. Implementing the tool within a treatment planning system would also provide more potential plan optimization parameters.
Sound source localization model of cube microphone array
Authors: Li Minzong , Wang Simeng , Tian Zhongxu
Published: April 2023

This paper conducts in‐depth research on the sound source localization technology of the microphone array and designs a sound source localization system based on the cube microphone array. Firstly, the sound source localization model is established using the cube microphone array combined with the spherical near‐field acoustic holography. Secondly, the numerical and sound source localization simulations are carried out using the spherical wave. Finally, the simulation and experiment of sound source location for sound at 100, 1000, and 2000 Hz are carried out using the model. Both simulation and experimental results show that when the sound source frequency is 100 and 1000 Hz, the location of the sound source can be accurately located by using the sound source localization model of a cube microphone array, and the sound field reconstruction error is low. When the sound source frequency is 2000 Hz, the location of the sound source cannot be located, and the sound field reconstruction error is very high, which will cause the misjudgment of the sound source location.
Effect of Homogenization Process on Microstructure of Al–Zn–Mg–Cu Aluminum Alloys
Authors: Huang Rensong , Yang Hongfu , Wan Li , Zheng Shanju , Li Mengnie , Koppala Sivasankar
Published: April 2023

Herein, the best homogenization process of 466.5 °C × 36 h + 490 °C × (14–26.4 h) that can completely eliminate the coarse phases σ[Mg(Zn, Al, Cu)2] and S(Al2CuMg) in the Al–Zn–Mg–Cu aluminum alloy is developed. The homogenization process is determined by the method of calculation phase diagram, and the experimental verification. It is shown in the results that, first, in the microstructure of the as‐cast alloys, the crystal structure of the σ[Mg(Zn, Al, Cu)2], Al7Cu2Fe, and Mg2Si phases is determined. Second, during the homogenization process, the σ[Mg(Zn, Al, Cu)2] phase dissolves and also transforms into the S(Al2CuMg) phase. Most importantly, the dissolution temperature range of the σ[Mg(Zn, Al, Cu)2], S(Al2CuMg), and Al7Cu2Fe phases is determined from 472.56 to 476.36 °C, from 484.09 to 485.39 °C, and from 540.18 to 547.23 °C, respectively. At best homogenization process, the residual Al7Cu2Fe phase area fraction ranges from 1.28 ± 0.16% to 1.60 ± 0.18%. In addition, dispersed η(MgZn2) phase precipitates in supersaturated Al‐matrix during differential scanning calorimeter heating. And, the concentration differences between the grain center and the eutectic of structure of Zn, Mg and Cu regression equations are established, which can provide some reference for the design of experimental parameters, thus reducing the experimental workload.
Flame Aerosol Synthesis of Metal Sulfides at High Temperature in Oxygen‐Lean Atmosphere
Authors: Pokhrel Suman , Stahl Jakob , Groeneveld Jan Derk , Schowalter Marco , Rosenauer Andreas , Birkenstock Johannes , Mädler Lutz
Published: April 2023

The development of a novel reactive spray technology based on the well‐known gas‐phase metal oxide synthesis route provides innumerable opportunities for the production of non‐oxide nanoparticles. Among these materials, metal sulfides are expected to have a high impact, especially in the development of electrochemical and photochemical high‐surface‐area materials. As a proof‐of‐principle, MnS, CoS, Cu2S, ZnS, Ag2S, In2S3, SnS, and Bi2S3 are synthesized in an O2‐lean and sulfur‐rich environment. In addition, the formation of Cu2S in a single‐droplet combustion experiment is reported. The multiscale approach combining flame sprays with single‐droplet combustion is expected to pave the way toward a fundamental understanding of the gas‐phase formation of metal sulfides in the future. The knowledge acquired can open the possibility for the development of a next‐generation gas‐phase technology facilitating the scalable synthesis of functional binary/ternary metal sulfides.
Interstitial Segregation has the Potential to Mitigate Liquid Metal Embrittlement in Iron
Authors: Ahmadian Ali , Scheiber Daniel , Zhou Xuyang , Gault Baptiste , Romaner Lorenz , Kamachali Reza D. , Ecker Werner , Dehm Gerhard , Liebscher Christian H.
Published: April 2023

The embrittlement of metallic alloys by liquid metals leads to catastrophic material failure and severely impacts their structural integrity. The weakening of grain boundaries (GBs) by the ingress of liquid metal and preceding segregation in the solid are thought to promote early fracture. However, the potential of balancing between the segregation of cohesion‐enhancing interstitial solutes and embrittling elements inducing GB de‐cohesion is not understood. Here, the mechanisms of how boron segregation mitigates the detrimental effects of the prime embrittler, zinc, in a Σ5 [001] tilt GB in α‐Fe (4 at.% Al) is unveiled. Zinc forms nanoscale segregation patterns inducing structurally and compositionally complex GB states. Ab initio simulations reveal that boron hinders zinc segregation and compensates for the zinc‐induced loss in GB cohesion. The work sheds new light on how interstitial solutes intimately modify GBs, thereby opening pathways to use them as dopants for preventing disastrous material failure.
Multi‐Stimuli‐Responsive and Mechano‐Actuated Biomimetic Membrane Nanopores Self‐Assembled from DNA
Authors: Xing Yongzheng , Dorey Adam , Howorka Stefan
Published: April 2023

In bioinspired design, biological templates are mimicked in structure and function by highly controllable synthetic means. Of interest are static barrel‐like nanopores that enable molecular transport across membranes for use in biosensing, sequencing, and biotechnology. However, biological ion channels offer additional functions such as dynamic changes of the entire pore shape between open and closed states, and triggering of dynamic processes with biochemical and physical stimuli. To better capture this complexity, this report presents multi‐stimuli and mechano‐responsive biomimetic nanopores which are created with DNA nanotechnology. The nanopores switch between open and closed states, whereby specific binding of DNA and protein molecules as stimuli locks the pores in the open state. Furthermore, the physical stimulus of high transmembrane voltage switches the pores into a closed state. In addition, the pore diameters are larger and more tunable than those of natural templates. These multi‐stimuli‐responsive and mechanically actuated nanopores mimic several aspects of complex biological channels yet offer easier control over pore size, shape and stimulus response. The designer pores are expected to be applied in biosensing and synthetic biology.
Reversing Acute Kidney Injury through Coordinated Interplay of Anti‐Inflammation and Iron Supplementation
Authors: Duan Ruixue , Li Yueping , Zhang Ruru , Hu Xuelan , Wang Yi , Zeng Jianfeng , Gao Mingyuan
Published: April 2023

Acute kidney injury (AKI) induced by ischemia reperfusion is closely related to mitochondrial dysfunction. Nicotinamide adenine dinucleotide (NAD+) can enhance the mitochondrial function and restrain the following inflammation, but it is hardly delivered and lacks renal targeting ability. To address these problems, herein, an ultrasmall Fe3O4 nanoparticle is used as a carrier to deliver nicotinamide mononucleotide (NMN), a precursor of NAD+. An outstanding sophistication of the current design is that once NMN is attached on the surface of Fe3O4 nanoparticles through its phosphate group, the remaining part is structurally highly similar to nicotinamide riboside, which provides an opportunity to deliver the NAD+ precursor into renal cells through nicotinamide riboside kinase 1 on the cell membrane. It is demonstrated that NMN‐loaded Fe3O4 nanoparticles can effectively reverse AKI induced by ischemia reperfusion. In‐depth studies indicate that a well‐timed iron replenishment following anti‐inflammation treatment plays a determined role in recovering AKI, which distinguishes the current study from previous strategies centering on anti‐ROS (reactive oxygen species), anti‐inflammation, or even iron elimination.
Defect‐Enriched Hollow Porous Carbon Nanocages Enable Highly Efficient Chlorine Evolution Reaction
Authors: Qu Huiqi , Li Bin , Ma Yiru , Xiao Zhenyu , Lv Zhiguo , Li Zhenjiang , Li Wei , Wang Lei
Published: April 2023

Metal‐free carbon‐based catalysts are crucial for the electrocatalytic chlorine evolution reaction (CER) to reduce the usage of noble metals and industrial cost. However, the corresponding catalytic activity of high overpotential and low durability hinders their wide application. Here, a hollow porous carbon (HPC) nanocage with a controlled oxygen electronic state around designed carbon defects for CER activity is reported. Alkali etching can bring defects in zeolite with a hollow structure. In a hard template strategy, the type of carbon defects is directly related to etching degree of the zeolite template. More importantly, the oxygen atoms can be “borrowed” from the zeolite framework by the defective carbon. The electron density around unsaturated O atoms can be decreased on the minor defects in carbon compared with that on large defects which is favorable for the adsorption of Cl−. Consequently, the as‐synthesized HPC nanocages with minor defects show excellent electrocatalytic performance for CER with a low overpotential of 94 mV at current density of 10 mA cm−2with good stability, which is superior to the commercial precious metal catalyst of dimensionally stable anode (DSA), and the best in the reported carbon materials. The designed carbon materials provide an option for metal‐free industrial catalysts with significant CER activities.
Interfacial Electron Distribution of Co Nanoparticles Supported on N‐Doped Mesoporous Hollow Carbon Spheres Endows Highly Efficient ORR, OER, and HER
Authors: Diao Jinxiang , Wang Shuya , Yang Zhenfeng , Qiu Yu , Xu Ruixin , Wang Weitao , Chen Kai , Li Xiaolin , Chao Tingting , Guo Xiaohui , Qu Yunteng
Published: April 2023

The tailoring of the charge transfer between support material and transition metal active phase is an effective strategy for fine tuning the electronic structure of the catalyst active site, and hence improving the activity and stability of the reaction. This works presents that Co nanoparticles supported on N‐doped mesoporous hollow carbon nanospheres (Co/NMHCS) decouple the effect of electronic structure on catalytic performance. The detailed experimental and theoretical results reveal the charge distribution at the Co/NMHCS interface due to N‐doped MHCS. With tuning the electron redistribution, the interface between Co nanoparticles and NMHCS as the active site shows the strong capability to adsorb and reduce the OOH* and proton, thus leading to the optimal ORR, OER, and HER activity in Co/NMHCS. Furthermore, Co/NMHCS‐based Zn–air battery exhibits high power density of 185 mW cm−2, and high gravimetric energy density of 753 mAh gZn−1. Density functional theory (DFT) reveals the electrons accumulate directly on the NMHCS support, which originates from an interplay between Co nanoparticles and the NMHCS support. This work provides constructive guidance for precisely regulating the interface electronic structures to achieve excellent electrocatalytic performance.
Bio‐Inspired Instability‐Induced Hierarchical Patterns Having Tunable Anisotropic Wetting Properties
Authors: Nagashima So , Suzuki Ko , Matsubara Seishiro , Okumura Dai
Published: April 2023

This paper introduces a method for the bottom‐up fabrication of bio‐inspired hierarchical patterns having tunable anisotropic wetting properties. The method exploits the surface instability of bilayers comprising a gold nanofilm attached to a substantially prestretched elastomer substrate. Upon film formation, highly aligned wrinkles spontaneously form on the surface owing to the surface instability driven by the compressive residual stress in the film. Thereafter, uniaxial compressive strain is applied to the film by prestretch relaxation of the substrate, which generates an array of high‐aspect‐ratio ridges on the surface. Consequently, hierarchical patterns comprising unidirectionally aligned ridges covered with wrinkles are obtained. Water droplets placed on surfaces having the aforementioned hierarchical patterns show direction‐dependent contact angles, resulting in elongated shapes, which indicates the presence of anisotropic wetting properties. The magnitude of wetting anisotropy can be tuned by simple control of the applied compressive strain and film thickness.
Wearable, Implantable, Parity‐Time Symmetric Bioresonators for Extremely Small Biological Signal Monitoring
Authors: Takamatsu Taiki , Sijie Yin , Miyake Takeo
Published: April 2023

Wireless biosensors are essential for digital transformations in health and medicine. Chipless resonant antenna‐based biosensors are affordable and tractable but are unsuitable for practical use because the common wireless sensing systems have low sensitivity caused by low quality factors. Herein, a parity‐time (PT) symmetric wireless biosensor is demonstrated that can detect small biological signals such as tear glucose level (0.1–0.6 mm) for diabetes diagnosis and blood lactate level (0.0–4.0 mm) for lactic acidosis diagnosis. The characteristics of the PT‐symmetric wireless sensing system are modeled by using an eigenvalue solution and input impedance, and the sensitivity enhancement at/near the exceptional point by using parallel inductance–capacitance–resistance resonators is experimentally demonstrated. 2000 times higher sensitivity for linear detection and 78% relative change for threshold‐based detection are achieved. Furthermore, the proposed PT‐symmetric wireless sensing system has sufficient tunability and robustness for use as a wearable/implantable device for monitoring small biological signals.
Microscale Metasurfaces for On‐Chip Magnetic Flux Concentration
Authors: Fourneau Emile , Arregi Jon Ander , Barrera Aleix , Nguyen Ngoc Duy , Bending Simon , Sanchez Alvaro , Uhlíř Vojtěch , Palau Anna , Silhanek Alejandro V.
Published: April 2023

Magnetic metamaterials have demonstrated promising perspectives to improve the efficiency of magnetic flux concentrators. In this work, the effects of downscaling these devices for on‐chip integration is investigated. The influence of the non‐linear magnetic response of the ferromagnetic components, their magnetic irreversibility, the formation of magnetic domains, as well as the effects of geometry and size of the devices are scrutinized. The results demonstrate that the implementation of metasurfaces at the microscale opens up new technological possibilities for enhancing the performance of magnetic field detectors and remotely charging small electric devices, thus paving the way toward new approaches in information and communication technologies.
Tetradentate Pt(II) Complex as Phosphorescent Sensitizer for Highly Efficient Green Organic Light‐Emitting Diodes with Low Efficiency Roll‐Off
Authors: Kim Seung Chan , Ryu Chan Hee , Lee Kang Mun , Lee Jun Yeob
Published: April 2023

Tetradentate Pt(II) complex (Pt‐Trz)‐sensitized green fluorescent organic light‐emitting‐diodes (OLEDs) are developed to improve the external quantum efficiency (EQE) of a green fluorescent emitter (PhtBuPAD). Pt(II) complex and a green fluorescent emitter with bulky blocking units are chosen to efficiently manage energy transfer in phosphor‐sensitized OLEDs. The Pt‐Trz phosphor‐sensitized fluorescent OLED with 2 wt% PhtBuPAD exhibits high EQE of 24.2% and maintains high EQE of 23.4% at a luminance of 3000 cd m−2, realizing low efficiency roll‐off of 3.8%. Moreover, high EQE is achieved even at a high PhtBuPAD‐doping concentration of 3 wt%. In addition, the 2 wt% PhtBuPAD‐doped phosphor‐sensitized device achieves high maximum power efficiency of 91.1 lm W−1, one of the highest power efficiencies among existing green sensitized devices. This study demonstrates that Pt‐Trz phosphor‐sensitized devices with an excellent triplet exciton utilization ability can achieve high EQE, low efficiency roll‐off, and weak doping concentration quenching simultaneously.
Large‐Area Structure‐Selective Synthesis of Symmetry‐Broken MoSe2 and Their Broadband Nonlinear Optical Response
Authors: Ahn Joohyeon , Ha Seongju , Choi Jungseok , Yeom Dong‐Il , Yoo Youngdong
Published: April 2023

Transition metal dichalcogenides (TMDCs) have various electronic and optical properties depending on their structure, so they can be used as a fascinating material in various applications including photonics, electronics, optoelectronics, and valleytronics. In particular, spiral TMDCs grown through the formation of screw dislocations exhibit novel electronic and optical properties different from layer‐by‐layer TMDCs. However, large‐area structure‐selective synthesis of TMDCs remains challenging. Here, this work reports for the first time the large‐area structure‐selective synthesis of monolayer MoSe2 and spiral MoSe2 using a flux‐controlled chemical vapor deposition method. Under a low MoSe2 flux condition, monolayer MoSe2 is synthesized, whereas thick spiral MoSe2 is synthesized under a high flux condition. Under a medium flux condition, both monolayer and spiral MoSe2 are synthesized. In addition, through the nonlinear optical (NLO) signal analysis of monolayer MoSe2 and spiral MoSe2, the giant enhancement of NLO signals induced by the combined effect of breaking inversion symmetry and the excitonic resonance effects in the synthesized MoSe2 is confirmed. Monolayer MoSe2 and spiral MoSe2 synthesized using this method are expected to be used as advanced optical materials for novel electronics, optoelectronics, and NLO applications.
Enhancing Circularly Polarized Emission by a Planar Chiral Dielectric Metasurface
Authors: Sun Yuwei , Hu Zhipeng , Shi Kezhang , Guo Tingbiao , Xing Yuxin , Jin Yi , He Sailing
Published: April 2023

Circularly polarized emission (CPE) has attracted great interest in optoelectronics, biosensing, etc. Here, a resonant planar chiral dielectric metasurface that can be constructed to provide a preferable way for CPE is demonstrated. The planar metasurface is easy to fabricate, and the corresponding far‐field circular polarization degree is extremely high and angle‐insensitive. The designed metasurface is made of a periodic array of in‐plane mirror‐asymmetric silicon pillar dimers and supports a low‐leakage chiral band‐edge mode. Experimentally, the photoluminescence of a thin film of PbS/CdS quantum dots coated on such a metasurface is enhanced by 57 times with the far‐field degree of circular polarization as high as 0.74. The planar platform provides a flexible and efficient way for manipulating CPE, in which other periodic coupling effects may also be adopted to enhance the light–matter interaction, such as quasi‐bound states in the continuum and lattice resonance.
Diversity‐Oriented Synthesis of Spiro‐ and 3‐Methylene‐hydroquinoline‐Indandiones via an Organobase‐Controlled Cascade Strategy
Authors: Lung Tsai‐Hui , Chen Yi‐Ru , Chang Chen‐Ling , Jeng Wey‐Chyng , Wu Pei‐Shan , Sambhaji Vagh Sandip , Marri Gangababu , Lin Yi‐Fang , Lin Wenwei
Published: April 2023

The catalyst‐controlled diversity‐oriented synthesis of spirohydroquinoline‐indandiones and 3‐methylenehydroquinoline‐indandiones from ortho‐sulfonamidophenyl‐substituted para‐quinone methides and allylidene‐indandiones is reported. The strategies utilized an organobase such as DMAP or TMG to control the reaction pathway chemoselectively, furnishing the corresponding products in 40–99% yields with excellent diastereoselectivities. The mechanistic studies revealed that spirohydroquinoline‐indandione was the kinetic product to afford 3‐methylenehydroquinoline‐indandione in the presence of TMG, which probably involved an unusual base‐initiated 1,3‐nitrogen rearrangement process.

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