bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Patch Substructuring Methods
Authors: Gander Martin , Halpern Laurence , Magoulès Frédéric , Roux François-Xavier 
Published: October 2007

Analysis of Patch Substructuring MethodsPatch substructuring methods are non-overlapping domain decomposition methods like classical substructuring methods, but they use information from geometric patches reaching into neighboring subdomains, condensated on the interfaces, to enhance the performance of the method, while keeping it non-overlapping. These methods are very convenient to use in practice, but their convergence properties have not been studied yet. We analyze geometric patch substructuring methods for the special case of one patch per interface. We show that this method is equivalent to an overlapping Schwarz method using Neumann transmission conditions. This equivalence is obtained by first studying a new, algebraic patch method, which is equivalent to the classical Schwarz method with Dirichlet transmission conditions and an overlap corresponding to the size of the patches. Our results motivate a new method, the Robin patch method, which is a linear combination of the algebraic and the geometric one, and can be interpreted as an optimized Schwarz method with Robin transmission conditions. This new method has a significantly faster convergence rate than both the algebraic and the geometric one. We complement our results by numerical experiments.
A Level Set Method in Shape and Topology Optimization for Variational Inequalities
Authors: Fulmański Piotr , Laurain Antoine , Scheid Jean-Francois , Sokołowski Jan 
Published: October 2007

A Level Set Method in Shape and Topology Optimization for Variational InequalitiesThe level set method is used for shape optimization of the energy functional for the Signorini problem. The boundary variations technique is used in order to derive the shape gradients of the energy functional. The conical differentiability of solutions with respect to the boundary variations is exploited. The topology modifications during the optimization process are identified by means of an asymptotic analysis. The topological derivatives of the energy shape functional are employed for the topology variations in the form of small holes. The derivation of topological derivatives is performed within the framework proposed in (Sokołowski and Żochowski, 2003). Numerical results confirm that the method is efficient and gives better results compared with the classical shape optimization techniques.
Validation of a Multivariable Model to Predict Suicide Attempt in a Mental Health Intake Sample
Authors: Papini Santiago , Hsin Honor , Kipnis Patricia , Liu Vincent X. , Lu Yun , Girard Kristine , Sterling Stacy A. , Iturralde Esti M. 
Published: March 2024

ImportanceGiven that suicide rates have been increasing over the past decade and the demand for mental health care is at an all-time high, targeted prevention efforts are needed to identify individuals seeking to initiate mental health outpatient services who are at high risk for suicide. Suicide prediction models have been developed using outpatient mental health encounters, but their performance among intake appointments has not been directly examined.ObjectiveTo assess the performance of a predictive model of suicide attempts among individuals seeking to initiate an episode of outpatient mental health care.Design, Setting, and ParticipantsThis prognostic study tested the performance of a previously developed machine learning model designed to predict suicide attempts within 90 days of any mental health outpatient visit. All mental health intake appointments scheduled between January 1, 2012, and April 1, 2022, at Kaiser Permanente Northern California, a large integrated health care delivery system serving over 4.5 million patients, were included. Data were extracted and analyzed from August 9, 2022, to July 31, 2023.Main Outcome and MeasuresSuicide attempts (including completed suicides) within 90 days of the appointment, determined by diagnostic codes and government databases. All predictors were extracted from electronic health records.ResultsThe study included 1 623 232 scheduled appointments from 835 616 unique patients. There were 2800 scheduled appointments (0.17%) followed by a suicide attempt within 90 days. The mean (SD) age across appointments was 39.7 (15.8) years, and most appointments were for women (1 103 184 [68.0%]). The model had an area under the receiver operating characteristic curve of 0.77 (95% CI, 0.76-0.78), an area under the precision-recall curve of 0.02 (95% CI, 0.02-0.02), an expected calibration error of 0.0012 (95% CI, 0.0011-0.0013), and sensitivities of 37.2% (95% CI, 35.5%-38.9%) and 18.8% (95% CI, 17.3%-20.2%) at specificities of 95% and 99%, respectively. The 10% of appointments at the highest risk level accounted for 48.8% (95% CI, 47.0%-50.6%) of the appointments followed by a suicide attempt.Conclusions and RelevanceIn this prognostic study involving mental health intakes, a previously developed machine learning model of suicide attempts showed good overall classification performance. Implementation research is needed to determine appropriate thresholds and interventions for applying the model in an intake setting to target high-risk cases in a manner that is acceptable to patients and clinicians.
50‐nm Gas‐Filled Protein Nanostructures to Enable the Access of Lymphatic Cells by Ultrasound Technologies
Authors: Shen Qionghua , Li Zongru , Wang Yixian , Meyer Matthew D. , De Guzman Marc T. , Lim Janie C. , Xiao Han , Bouchard Richard R. , Lu George J. 
Published: March 2024

AbstractUltrasound imaging and ultrasound‐mediated gene and drug delivery are rapidly advancing diagnostic and therapeutic methods; however, their use is often limited by the need for microbubbles, which cannot transverse many biological barriers due to their large size. Here, the authors introduce 50‐nm gas‐filled protein nanostructures derived from genetically engineered gas vesicles(GVs) that are referred to as 50 nmGVs. These diamond‐shaped nanostructures have hydrodynamic diameters smaller than commercially available 50‐nm gold nanoparticles and are, to the authors’ knowledge, the smallest stable, free‐floating bubbles made to date. 50 nmGVs can be produced in bacteria, purified through centrifugation, and remain stable for months. Interstitially injected 50 nmGVs can extravasate into lymphatic tissues and gain access to critical immune cell populations, and electron microscopy images of lymph node tissues reveal their subcellular location in antigen‐presenting cells adjacent to lymphocytes. The authors anticipate that 50 nmGVs can substantially broaden the range of cells accessible to current ultrasound technologies and may generate applications beyond biomedicine as ultrasmall stable gas‐filled nanomaterials.
Spacer Conformation Induced Multiple Hydrogen Bonds in 2D Perovskite toward Highly Efficient Optoelectronic Devices
Authors: Dong Kailian , Yang Xiangfeng , Yao Fang , Cong Hengjiang , Zhou Hai , Zhou Shun , Cui Hongsen , Wang Shuxin , Tao Chen , Sun Chengliang , Fu Huahua , Ke Weijun , Fang Guojia 
Published: March 2024

AbstractTwo‐dimensional (2D) Dion–Jacobson (DJ) perovskites typically outperform Ruddlesden–Popper (RP) analogs in terms of photodetection (PD). However, the mechanism behind this enhanced performance remains elusive. Theoretical calculations for elucidating interlayer spacer conformation‐induced multiple hydrogen bonds in 2D perovskite are presented, along with the synthesis of DPAPbBr4 (DPB) single crystals (SCs) and their PD properties under X‐ray/ultraviolet (UV) excitation. The high‐quality DPB SC enhances PD with exceptional photoresponse attributes, including a high on/off ratio (4.89 × 104), high responsivity (2.44 A W⁻1), along with large dynamic linear range (154 dB) and low detection limit (7.1 nW cm⁻2), which are currently the best results among 2D perovskite SC detectors, respectively. Importantly, high‐resolution images are obtained under UV illumination with weak light levels. The SC X‐ray detector exhibits a high sensitivity of 663 µC Gyair⁻1 cm–2 at 10 V and a detection limit of 1.44 µGyair s⁻1. This study explores 2D DJ perovskites for efficient and innovative optoelectronic applications.
Anti‐Reflective Graded‐Index Metasurface with Correlated Disorder for Light Management in Planar Silicon Solar Cells
Authors: Dhawan Prerak , Gaudig Maria , Sprafke Alexander , Piechulla Peter , Wehrspohn Ralf B. , Rockstuhl Carsten 
Published: March 2024

AbstractRecently, many research efforts have been dedicated to improving light coupling into solar cells and reducing optical losses. Promising candidates regarding scalability include direct nano‐structuring of the absorber layer, anti‐reflective (AR) coatings, or combining both, e.g., pyramidal textures with a conformal coating. However, many of these methods are either insufficient or infeasible for application in thin solar cells. Moreover, approaches based on directly texturing the silicon interface simultaneously strongly increase surface recombination, thus degrading the electronic properties of the solar cell. To circumvent these issues, conformal graded‐index metasurfaces with a correlated positional disorder for light trapping in solar cells are proposed and experimentally demonstrated in this contribution. When considered as a part of a prototypical solar cell geometry, a broadband reduction in reflection is observed that results in photocurrent enhancement. The combined consideration of disorder and conformal graded‐index layers outperforms structures containing only one of these components. The computational guidance toward optimized designs promises to adjust the framework to other settings. The possibility for large‐scale fabrication of the samples paves the way toward a future generation of supporting photonic structures in solar cells.
Sterically Wrapped Oxygen‐Bridged Boron Derivatives for High‐Performance Blue Organic Light‐Emitting Diodes
Authors: Wang Han‐Yang , Xie Feng‐Ming , Li Hao‐Ze , Zhang Kai , Zhu Yuan‐Ye , Shi Hao‐Nan , Li Yan‐Qing , Tang Jian‐Xin 
Published: March 2024

AbstractNear ultraviolet (NUV) organic light‐emitting diodes (OLEDs) have great advantages in the field of light excitation sources, chemical and biological sensors, etc. However, the molecular design of NUV emitters still faces the challenges of spectral broadening and red‐shift. In this study, attaching weak oxygen‐bridged triarylboron acceptor to weak carbazolyl donor is able to address intractable problems by weakening donor–acceptor (D–A) charge transfer. Simultaneously, sterically wrapped and modified oxygen‐bridged triarylboron acceptor by bulk substituents (multiple carbazolyl) can suppress intermolecular π–π stacking through steric hindrance effect. These design strategies are able to obtain short‐wavelength, narrow‐band emission, and great color purity. As a result, carbazolyl derivatives xCz‐BO‐based (x = 2, 3, 4, 5) emitters show EL emission peaks from 406 to 422 nm in the NUV light region and small full‐width at half‐maximums (FWHMs) of 32–41 nm over a wide range of dopant concentrations (10–40 wt.%). The most violet Commission International de I'Eclairage (CIE) color coordinate is (0.16, 0.03). Moreover, 5Cz‐BO can be employed as host for vacuum‐/solution‐processed blue OLEDs and these devices exhibit high performance with EQEs of over 20%.
Mini Light‐Emitting Diode Technology with High Quantum Efficient NIR‐II Partially Inverse Spinel MgGa2O4:Cr3+,Ni2+ Nanophosphors
Authors: Satpathy Aishwarya , Huang Wen‐Tse , Liu Tzu‐Hsuan , Su Ting‐Yi , Zhang Wei , Kamiński Mikołaj , Grzegorczyk Maciej , Chen Jia‐Hao , Cherng Ding‐Hua , Lu Kuang‐Mao , Chen Xueyuan , Mahlik Sebastian , Liu Ru‐Shi 
Published: March 2024

AbstractThe increasing demand for second near‐infrared (NIR‐II) region materials, which retain the advantage of minimal scattering and immense applications in the medical and NIR spectroscopy field, has led to considerable research in this region. A mini light‐emitting diode (mini‐LED) is essential for backlighting liquid crystal displays, indicating the need for the small size of phosphors. However, current market phosphors must be more significant to be a viable option for mini‐LEDs. This scenario necessitates the synthesis of small‐sized phosphors to be used in mini‐LEDs. In this work, a mesoporous silica nanoparticle (MSN) and incorporated the Mg1−yGa2−xO4:xCr3+,yNi2+ system is fabricated. The structural investigation confirmed the single phase of MgGa2O4 with a pore size of 2.73 nm for the MSN. The results showed a steady NIR‐II signal at 1270 nm and an enhanced energy transfer with a high quantum yield of 79.2% for a nanophosphor. The mini‐LED package revealed a 1000–1600 nm signal, qualifying the nanophosphor for realistic applications. This work can make provisions for various NIR‐II nanophosphors in the LED industry.
Pressure‐Induced Symmetry Breaking Enables Retainable Upconversion Photoluminescence Enhancement in Lanthanide Oxyfluoride
Authors: Wen Ting , Wang Yiming , Peng Shang , Liu Xuqiang , Cheng Haoming , Liu Ke , Ma Yingying , Li Chen , Yang Wenge , Wang Yonggang 
Published: March 2024

AbstractPressure‐induced performance enhancement of a given material is an emerging phenomenon, however, among the various known examples very few enhanced properties can retain to ambient conditions. Both new structural mechanism and new material systems are the key challenge to achieve recoverable properties via pressure treatment. Herein, an “Er‐rich” erbium oxyfluoride ErOF is reported with retainable enhanced upconversion (UC) emission by high pressure treatment. The UC emission increases to more than twice the intensity of its pristine state, and followed by additional improvement to 5.1‐fold increase by heat treatment at 100 °C. The site symmetry breaking of Er3+ ions along with the crystal phase transition from Rm to Pnma, revealed by X‐ray diffraction, is believed to be the underlying reasons for the enhanced UC emission after release. Further, high‐resolution transmission electron microscopy (HRTEM) study reveals that the defects relieved with heat treatment might account for the UC emission enhancement in the released sample. Time‐resolved spectra and I‐P curves are measured comparatively to further illustrate the intrinsic mechanism of UC processes. The findings open up a window to advance UC performance through structure optimization by pressure engineering, thus facilitating its potential applications under ambient conditions.
Efficient OLEDs with Alleviated Efficiency Roll‐Off Based on MR‐TADF Materials Containing Indolo[3,2,1‐jk]carbazole
Authors: Song Shi‐Quan , Yip Ching‐Fai , Liu Qi‐Ming , Zhong Xiao‐Sheng , Wang Yi , Zheng You‐Xuan 
Published: March 2024

AbstractThe multiple resonance thermally activated delayed fluorescence (MR‐TADF) materials can meet the requirement of a high color gamut of displays due to their narrowband emission. However, most reported organic light‐emitting diodes (OLEDs) based on MR‐TADF materials suffer from severe efficiency roll‐off. Herein, three green MR‐TADF emitters, p‐ICz‐BNCz, m‐ICz‐BNCz, and dm‐ICz‐BNCz, are obtained by introducing bulky indolo[3,2,1‐jk]carbazole (ICz) units into the classical DtBuCzB skeleton at the para or meta positions relative to the boron‐substituted phenyl ring. Compared with the para‐substitution of ICz, the meta‐substitution not only increases the reverse intersystem crossing rate constants of m‐ICz‐BNCz and dm‐ICz‐BNCz by nearly three times, but also makes their configurations more twisted. The two factors work together to improve the utilization of triplet excitons of the emitters, showing photoluminescence quantum yields exceeding 90%. As a result, the two corresponding OLEDs exhibit maximum external quantum efficiency (EQEmax) values of 28% and 32.9%, respectively, with low‐efficiency roll‐off. At the high brightness of 1000 cd m−2, the EQE values of the two devices still maintain at 19.3% and 25.0%, respectively. In addition, green emissions with Commission Internationale de l'Eclairage coordinates of (0.20, 0.70) and (0.30, 0.67) are also observed.
Li Substitution Strategy for Enhancing Quantum Efficiency and Improving Thermal Stability of Red‐Light Mn4+‐Activated Fluoride for Wide‐Gamut Displays
Authors: Tang Wenyu , Wang Yuanjing , Zhou Yayun , Zhang Chuang , Chen Zhen , He Fanquan , Song Enhai , Zhang Qinyuan 
Published: March 2024

AbstractMn4+‐activated red‐light fluorides are widely used in high‐quality displays, due to the narrow‐spectral emission. However, achieving exceptional chromaticity coordinates and appropriate quantum efficiency (QE) at the same time is a great challenge. Herein, a Li substitution strategy is proposed for enhancing QE and improving the thermal stability of red‐light Mn4+‐activated Cs2NaGaF6 (CNGF). The external quantum efficiency (EQE) of optimal Cs2NaGaF6: Mn4+, Li+ (CNGF: Mn4+, Li+) is improved from 15.79% to 33.61% and thermal stability increases from 68.4% to 85.5% (intensity at 150 °C relative to room temperature). EQE enhancement mechanism on the strategy is explored that Li substitution increases the local structural distortion of Mn4+ for relieving the parity forbidden, and promotes Mn4+ doping in the host lattice, which provides new insights for improving the QE of Mn4+ non‐equivalent doped fluorides. Moreover, with exceptional chromaticity coordinates of (0.7029, 0.2970), optimal sample CNGF: 4.8 mol% Mn4+,0.9 mol% Li+ can be used to fabricate white light‐emitting diode (w‐LED) backlight, which obtains wide color gamut of 110.68% National Television Standards Committee (NTSC) and high luminous efficacy of 110.57 lm W−1, indicating that CNGF: Mn4+, Li+ is a promising candidate for the next generation of wide gamut and efficient displays.
Molecular Engineering toward Broad Color‐Tunable Emission of Pyrene‐Based Aggregation‐Induced Emission Luminogens
Authors: Liu Wei , Li Shaoling , Xie Zhixin , Huang Kaiwei , Yan Kai , Zhao Yu , Redshaw Carl , Feng Xing , Tang Ben Zhong 
Published: March 2024

AbstractA molecular design strategy for the precise regulation of full‐color‐tunable emission organic luminescence materials is not yet systematically established for pyrene chemistry. To fabricate color‐tunable and highly‐efficiency pyrene‐based emitters, this article presents novel pyrene‐based molecules with donating‐π‐accepting structures, which exhibit bright, relatively narrow‐band FWHM emission, broad color‐tunable from deep blue (439 nm) to orange‐red (599 nm) both in solution and in the solid state. Moreover, the compounds 2a, 2d–g exhibit typical aggregation‐induced emission (AIE) characteristics, with an enhanced fluorescence quantum yield in the solid state. The experimental results indicated that the presence of the sterically bulky meta‐substituted biphenyl adopts an out‐of‐plane twist conformation, which can strengthen the rigidity of the molecular conformation and suppress the intermolecular π–π stacking in the aggregated state, resulting in an enhanced emission in the solid state. The prepared pyrene‐based AIEgens are applied as fluorescent inks to write Chinese characters and art with a vivid pattern. Thus, this article not only presents an efficient molecular strategy to construct pyrene‐based AIEgen with broad color‐tunable emission properties for practical applications, but also display a powerful combination of the strong alliance between the advanced luminescent materials, art and Chinese traditional culture.
Stabilizing Phosphorene‐Like Group IV–VI Compounds via van der Waals Imprinting for Multistate Ferroelectricity and Tunable Spin Transport
Authors: Muzaffar Muhammad Usman , Zhang Chuanbao , Zhang Shunhong , Cui Ping , Zhang Zhenyu 
Published: March 2024

AbstractLayered group IV–VI compounds (i.e., SnSe, SnS, GeSe, and GeS) in the puckered structure resembling black‐phosphorene (BlackP) have attracted increasing interest because of their intriguing ferroic orders and outstanding thermoelectric properties. By invoking the guiding principles of isovalency and isomorphism for promoting van der Waals epitaxy, and based on comprehensive first‐principles calculations, here it is shown that the typically metastable BlackP‐like GeTe can be readily stabilized on the (001) surface of isostructural SnSe. Importantly, the ferroelectricity of such a BlackP‐like GeTe monolayer can be substantially enhanced compared to the freestanding state, due to the substrate enlarged in‐plane polar displacements. The GeTe/SnSe heterobilayer exhibits multiple ferroelectric/ferrielectric polarization states, which can be exploited for high‐density memory devices. These mutually switchable polarization states are also shown to be internally locked with the spin polarization of the valence/conduction bands with pronounced Rashba spin‐orbit splitting and Berry curvature dipole. These findings highlight the intuitive yet enabling power of van der Waals imprinting in growing novel 2D materials for enriched functionalities.
High‐Entropy La‐(Bi0.2Na0.2Ba0.2Sr0.2Ca0.2)TiO3 Ceramic with Ultrastable Dielectric Performance within 327–689 K and up to 7 GPa
Authors: Wu Jie , Guo Jian , Ren Yifeng , Yang Yanping , Zhang Ziyou , Dong Hongliang , Zhang Shan‐Tao , Chen Zhiqiang , Deng Yu 
Published: March 2024

AbstractTo meet the needs of energy storage under high temperature and high pressure, a high‐entropy relaxor ferroelectric ceramic, La‐modified (Bi0.2Na0.2Ba0.2Sr0.2Ca0.2)TiO3 is prepared, which has excellent thermal and mechanical stability. At the wide temperature range of 327–689 K (tan δ < 0.01) and below ≈7 GPa, the material shows extraordinary functional performance. Comprehensive study indicates that the ceramic possesses a single‐phase cubic perovskite structure, and as the pressure increases, the material undergoes a transition at ≈8 GPa, in which enormous large grains crack into smaller grains, but the space group does not change. In addition, with further compression, the grains begin to rotate and re‐orientate at ≈9 GPa. Based on the investigations, it is considered that the suitable doping of multiple cations can effectively improve the stability of ceramics, and it also paves the experimental way to further study thermally and mechanically stable high‐entropy ceramics.
Corn response to strip‐tillage and phosphorus fertilization in the Northern Great Plains
Authors: Rogalsky Magdalena , Tiessen Kevin H. D. , Flaten Don , Lawley Yvonne , Tenuta Mario , Heard John 
Published: March 2024

AbstractStrip‐tillage is an emerging conservation tillage/residue management system for corn production in the Northern Great Plains. Producers in Manitoba are becoming more interested in strip‐tillage as it may provide many of the soil conservation benefits of no‐tillage production without potential limitations of cold soils in the spring common to this region. A 2‐year study evaluated corn (Zea mays L.) response to phosphorus (P) fertilization in strip‐tillage and conventional tillage systems. Fertilization treatments included a control (no P), two rates of P (30 and 60 kg P2O5 ha−1), applied as monoammonium phosphate (11–52–0) either in the fall with a strip‐tillage unit (as a deep‐band, 10–13 cm deep) or in the spring with a corn planter (as a side‐band, 5 cm beside and 2.5 cm below the seed). Spring side‐banded P treatments increased early‐season biomass at 2 of 4 site‐years by up to 103% compared to the unfertilized controls. At the same 2 site‐years, banded P treatments reduced days to silking by 2–3 days, compared to the unfertilized controls. Across all site‐years, spring side‐banded P treatments increased grain yield by an average of 467 kg ha−1 and decreased grain moisture content by 9 g kg−1 compared to the unfertilized control. Overall, side‐banded P at planting was agronomically superior to precision fall deep‐banding. There was also no agronomic penalty for corn grown with strip‐tillage, compared to conventional tillage, suggesting that strip‐tillage is an agronomically promising practice for corn production in southern Manitoba.