bluuebunny/crossref_metadata_2025_split huggingface dataset:
A High‐Precision and Wide‐Range DPFM/DPWM Generation Method Using FPGA
Authors: Lu Fuchao , Zhang Zheng‐Quan 
Published: February 2025

ABSTRACTCurrent digital pulse width modulation (DPWM) implementations prioritize high‐precision duty cycle control, but they suffer from relatively lower frequency adjustment precision, which is inadequate for applications requiring high frequency resolution, such as RF Class‐D power amplifiers. To address this limitation, this paper introduces a cost‐effective FPGA‐based method for generating multichannel high‐precision and wide‐range digital pulse frequency modulation (DPFM) signals. This method allows for the simultaneous generation of multiple adjustable duty cycle and frequency pulses, with precise control over the phase shift between different pulse channels. This solution innovatively enables high‐precision regulation of both period and duty cycle across a broad frequency spectrum. It utilizes a hybrid architecture that integrates multiple counters with delay units, thus expanding the adjustable range for both cycle and duty cycle while preserving high precision. In this paper, employing IDELAYE2 as the delay unit, the PFM signals generated have a minimum frequency of 12 Hz and a maximum of 15 MHz, with all adjustments—period, duty cycle, and phase shift—achieving an accuracy of 39 ps. The scheme's validity is confirmed using the Xilinx ZYNQ XC7Z100 series FPGA, demonstrating an average deviation of approximately 6 ps between the nominal and actual measured values, linearity = 0.9993.
Possible influence of water level management on nutrient flux in nearshore sediments of Kabetogama Lake, Minnesota, USA
Authors: Larson James H. , Bailey Sean W. , Maki Ryan P. , Christensen Victoria G. , Stelzer Erin A. , Smith James C. , LeDuc Jaime F. , McWhorter Seth 
Published: February 2025

AbstractLake water level fluctuations are an important factor driving variation in many ecosystem processes. The nearshore sediments that are periodically exposed and re‐inundated can develop distinct physical and chemical characteristics, especially in relationship to the organic matter content of the sediments and the particle size distribution. These sediment characteristics in turn can alter the flux of nitrogen (N) and phosphorus (P) from sediments into the water column when sediments are inundated. Here, we used intact sediment core experiments across a range of sediment inundation frequencies to estimate the effect of inundation frequency on sediment nutrient flux in Kabetogama Lake, Minnesota, USA. We observed associations between elevation or inundation frequency and some sediment characteristics, but in a structural equation model, inundation frequency and the sediment properties we measured were poorly related to inorganic nutrient flux. On the other hand, inundation frequency did have a moderate association with organic N and P flux from sediments, which could be due to decay of terrestrial organic matter that accumulates on exposed sediments. We used our parameterized structural equation model to estimate how three different water level management regimes employed over the past 50 years could influence organic N and P flux from sediments. The models suggested more recent water level management regimes reduced organic N and P flux by 9%–13% and 5.9%–9.8%, respectively. Nearshore sediment flux could sustain and influence harmful algal blooms that occur in this lake, and these fluxes could be influenced by water level management.
Electrospun Carbon Nanofibers for Clean Energy Applications: A Comprehensive Review
Authors: Jeon Dogyeong , Sagong Mingyu , Kim Min Soo , Nam Jong Seok , Park Heejun , Kim Il‐Doo 
Published: February 2025

ABSTRACTThe development of clean energy technologies is increasingly dependent on advanced materials capable of enhancing energy storage and conversion efficiencies. Carbon nanofibers (CNFs), known for their unique fibrous morphology, high aspect ratio, high electrical conductivity and specific surface area, particularly with post‐treatment, as well as their chemical robustness, have emerged as exceptional candidates for a variety of clean energy applications. This review comprehensively provides the synthesis, structural modification, and surface activity tuning of electrospun CNFs, with a focus on their utilization in energy storage devices such as lithium‐metal batteries, lithium‐sulfur batteries, lithium‐air batteries, and supercapacitors as well as in energy conversion systems, including water splitting, fuel cells, electrochemical CO2 reduction technologies, and solar thermal‐driven water evaporation. The discussion delves into the fabrication methodologies for electrospun CNFs, highlighting the critical role of structural modifications and surface activity tuning in enhancing material performance. Recent progress in the application of CNFs‐based nanomaterials for clean energy solutions is presented, demonstrating their potential to significantly advance the efficiency and sustainability of energy‐related technologies. Furthermore, this review identifies existing challenges and outlines future research directions, aiming to provide readers with a comprehensive understanding of state‐of‐the‐art CNFs fabrication techniques and their applications in the fields of energy and environmental science. This work serves as a valuable resource for researchers in materials science, nanotechnology, and environmental science, guiding the further development and deployment of CNFs for sustainable energy solutions.
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Dual‐Responsive Multi‐Functional Silica Nanoparticles With Repaired Mitochondrial Functions for Efficient Alleviation of Spinal Cord Injury
Authors: Gao Guibin , Li Juanjuan , Ma Yanming , Xie Min , Luo Jianxian , Wang Ke , Peng Cheng , Yang Hua , Chen Tianjun , Zhang Guowei , Ouyang Jiang , Lin Hongsheng , Ji Zhisheng 
Published: February 2025

ABSTRACTPreserved/rescued mitochondrial functions have a significant effect on maintaining neurogenesis, axonal carriage, and synaptic plasticity following spinal cord injury (SCI). We fabricated an ingenious redox‐responsive strategy for commanded liberation of NADH (reduced form of nicotinamide‐adenine dinucleotide) by bioactive diselenide‐containing biodegradable mesoporous silica nanoparticles (Se@NADH). The nanocarrier‐embedded NADH can be liberated in a controlled pattern through the cleavage of diselenide bonds in the presence of reactive oxygen species (ROS) or glutathione (GSH). The NAD+ was regenerated by the reactions between released NADH and harmful ROS to antagonize mitochondrial dysfunction and increase ATP synthesis, promoting axon regeneration across SCI areas. This nanosystem increased the stability of NADH during prolonged blood circulation time, reduced the clearance rate, exhibited significant anti‐inflammatory as well as neuroprotective effects and enhanced the regeneration of electrophysiological conduction capacity across SCI areas. Importantly, Se@NADH suppressed glial scar formation and promoted neuronal generation as well as stretching of long axons throughout the glial scar, thereby improving actual restoration of locomotor functions in mice with SCI and exerting ascendant therapeutic effects. Targeting of mitochondrial dysfunction is a potential approach for SCI treatment and may be applied to other central nervous system diseases.
Mechanical Properties of the Cortex in Older Adults and Relationships With Personality Traits
Authors: Twohy Kyra E. , Kramer Mary K. , Diano Alexa M. , Bailey Olivia M. , Delgorio Peyton L. , McIlvain Grace , McGarry Matthew D. J. , Martens Christopher R. , Schwarb Hillary , Hiscox Lucy V. , Johnson Curtis L. 
Published: February 2025

ABSTRACTAging and neurodegeneration impact structural brain integrity and can result in changes to behavior and cognition. Personality, a relatively stable trait in adults as compared to behavior, in part relies on normative individual differences in cellular organization of the cerebral cortex, but links between brain structure and personality expression have been mixed. One key finding is that personality has been shown to be a risk factor in the development of Alzheimer's disease, highlighting a structure–trait relationship. Magnetic resonance elastography (MRE) has been used to noninvasively study age‐related changes in tissue mechanical properties because of its high sensitivity to both the microstructural health and the structure–function relationship of the tissue. Recent advancements in MRE methodology have allowed for reliable property recovery of cortical subregions, which had previously presented challenges due to the complex geometry and overall thin structure. This study aimed to quantify age‐related changes in cortical mechanical properties and the relationship of these properties to measures of personality in an older adult population (N = 57; age 60–85 years) for the first time. Mechanical properties including shear stiffness and damping ratio were calculated for 30 bilateral regions of the cortex across all four lobes, and the NEO Personality Inventory (NEO‐PI) was used to measure neuroticism and conscientiousness in all participants. Shear stiffness and damping ratio were found to vary widely across regions of the cortex, upward of 1 kPa in stiffness and by 0.3 in damping ratio. Shear stiffness changed regionally with age, with some regions experiencing accelerated degradation compared to neighboring regions. Greater neuroticism (i.e., the tendency to experience negative emotions and vulnerability to stress) was associated with high damping ratio, indicative of poorer tissue integrity, in the rostral middle frontal cortex and the precentral gyrus. This study provides evidence of structure–trait correlates between physical mechanical properties and measures of personality in older adults and adds to the supporting literature that neurotic traits may impact brain health in cognitively normal aging.
Increasing Trends of Shallow Groundwater Warming in Vienna's Urban Aquifers
Authors: Kaminsky Eva , Laaha Gregor , Steiner Cornelia , Buga‐Nyéki Eszter , Englisch Constanze , Griebler Christian , Stumpp Christine 
Published: February 2025

ABSTRACTShallow groundwater in many cities around the world is subject to elevated temperatures that pose a risk to the groundwater quality and ecosystems. The objective of this study is to assess the suitability of different trend estimation methods for groundwater temperature and to specifically investigate the spatio‐temporal long‐term changes of water temperature in the urban groundwater of Vienna. Twenty‐year data records (2001–2020) from different sources were used to assess changes in air, soil, river and groundwater temperature regarding their annual mean and extreme percentile values. The effects of data quality, different trend methods, and various time periods of analysis were investigated. Block bootstrapping in combination with the Mann–Kendall trend test was found to be a suitable method for determining the significance of mean trends if the time‐series are short (10 years), as the underlying assumptions are lowest among all approaches. Between 2001 and 2020, the average annual temperature in Vienna increased by 0.9 K/decade for shallow groundwater and by 0.8 K/decade for air. However, the increase is not linear and has intensified in the later decade with an increase of 1.4 K/decade. The trends in extreme temperatures, represented by the lower (cold) / upper (warm) 10th percentile of air, soil and groundwater temperatures in the quantile regression, show the strongest increase in the lower 10th percentile of all air and soil temperatures. For groundwater, these extreme value trends are site‐specific and influenced by urban infrastructure and the interaction of groundwater with river water. These results underline the importance of spatially and temporally high‐resolution data and highlight the need for site‐specific aquifer characterisation for the sustainable use of shallow geothermal energy for heating and cooling. The trend of GWT rise in the urban aquifer needs to be considered in water management to avoid possible negative consequences for water quality and ecology.
Pediatric endoscopic ultrasound‐guided liver biopsy: 3‐year experience
Authors: Schwartz Talia S. , Mouzaki Marialena , Berklite Lara , Lopez‐Nunez Oscar F. , Miethke Alexander , Xanthakos Stavra A. , Vitale David S. 
Published: February 2025

AbstractObjectivesLiver biopsy is the gold standard for diagnosing and staging liver diseases. Endoscopic ultrasound‐guided liver biopsy (EUS‐LB) has been reported in adults with equivalent or better safety profiles than percutaneous liver biopsies. The aim of this study was to retrospectively assess the safety and efficacy of EUS‐LB in pediatric patients.MethodsThis was a retrospective chart review of consecutive pediatric patients undergoing EUS‐LB at Cincinnati Children's Hospital Medical Center from March 2020 to April 2023. Patients ≤21 years old were included. EUS‐LB was performed via fine‐needle biopsy technique with transduodenal and/or transgastric approach. Histology was independently reviewed by one of two expert pathologists, including length (cm) and complete portal tract (CPT) number per the American Association for the Study of Liver Diseases (AASLD) adequacy criteria. Demographics, clinical data, technical information, diagnostic success, and adverse events were recorded.ResultsEighty‐three patients were included in the analysis, with various indications that required liver biopsy. All biopsies achieved diagnostic and technical success, with 77 (93%) meeting both AASLD criteria for adequacy. Most patients (57, 69%) underwent biopsy of both hepatic lobes, with an overall median of two needle passes. Total specimen length was a median of 7.9 cm (interquartile range [IQR] 5.2–10.3), and the median maximum intact specimen was 4.2 cm (IQR 3.1–5.4). The median CPT number was 24 (IQR 17–32) per patient. Four mild adverse events (5%) occurred; none involved bleeding.ConclusionsEUS‐LB was well tolerated and yielded samples that were technically and diagnostically successful in a pediatric population, with comparable safety to percutaneous liver biopsy.
Quantum Holographic Microscopy
Authors: Kong Ling‐Jun , Zhang Jingfeng , Zhang Zhuo , Zhang Xiangdong 
Published: February 2025

AbstractQuantitative phase microscopy (QPM) techniques are widely investigated for imaging transparent specimens, such as cells and tissues. The sensitivity and resolution of conventionally used QPM are fundamentally limited by environmental noise. Recently, quantum phase microscopy has been proposed. The research on it has made some progress and has shown many advantages over the classical one, such as greater robustness and higher contrast. However, the phase resolution of existing quantum phase microscopies remains very low, often confined to the qualitative measurement level. Here, to resolve these practical limitations, we introduced polarization entanglement‐enabled quantum holographic technology into the microscopy system and constructed a new type of quantum phase microscopy, namely quantum holographic microscopy. By improving the existing quantum holographic scheme, our microscope system can be used to measure both various non‐biological phase samples and label‐free biological samples. The experimental results show that the phase resolution is improved by an order of magnitude compared with that of existing quantum phase microscopes. Moreover, the system has good robustness and can still obtain clear images in the presence of strong classical noise. The newly constructed quantum microscopic system is expected to have broad applications in industrial production, medicine, biological research, and other fields.
High Quantum Yields Enhancement Induced by Processable AIEgens Doped Photonic Crystal Powders for Bright Luminescence and Structural Colors
Authors: Qiao Chuyu , Liu Tianyi , Wu Suli 
Published: February 2025

AbstractThe composite solid‐state structure of photonic crystals (PCs) and aggregation‐induced‐emission agents (AIEgens) exhibits potential for various applications, owing to its remarkable anti‐aggregation quenching effect and exceptional fluorescence tuning ability. Herein, TVP molecules integrate into PCs by one‐step co‐assembly of TVP molecules and PMMA colloidal spheres. By carefully optimizing the assembly conditions, a kind of AIEgens doped structures fabricate, which exhibit vibrant structural color, bright fluorescence, and especially impressive luminescence quantum yield up to 0.838. Importantly, after being grounded into micron‐scale PC powders, the AIEgens doped PCs retain their good optical properties and exhibit exceptional light and thermal stability. Compared with the polymer film or deposited films on substrates of the previously reported composite PCs and AIEgens, the powder state endows them with good processibility, enabling them to be seamlessly integrate with various polymers to meet the diverse requirements of different processing techniques. The good processability facilitates the production of 2D or 3D models that possess both vivid structural color and bright luminescence. Moreover, the co‐assembly strategy of fabricating AIEgens doped PCs powders can be employed for the colloidal spheres with varying diameters or diverse AIEgens, thereby enabling the generation of adjustable luminescence and structural color, thus substantially broadening the potential application scenarios.
Tungsten inert gas welding of zircaloy sheet: Mechanical properties and microstructural characterization
Authors: Munusamy V. , Raju G. , Veeman D. , Subramaniyan M. K. 
Published: February 2025

AbstractA zirconium‐based alloy called zircaloy‐2 is well known for its exceptional resistance to corrosion and low cross‐sectional absorption of neutrons, which makes it a vital component for fuel cladding application in the nuclear industry. Tungsten inert gas welding is an effective method for joining zircaloy due to its precise heat control and inert gas shielding, ensuring high‐quality welds with minimal contamination. This technique is particularly advantageous for applications demanding excellent corrosion resistance and mechanical properties. Fabrication of zircaloy‐2 sheets through tungsten inert gas welding, guided by optimal process parameters derived from extensive trial‐and‐error testing, has yielded welds with impeccable quality suitable for deployment in nuclear, aerospace, and marine sectors. Analysis of welded microstructure of material revealed the presence of columnar and equiaxed dendrites near the weld metal, primarily composed of α‐zirconium and β‐zirconium phases, as evidenced by optical microscopy and x‐ray diffraction. These microstructural variations, induced by constitutional supercooling and thermal histories, have significantly enhanced the mechanical properties of welded pipe. There is an increase of 4.3 % in strength as tensile strength of 477 MPa, while base metal exhibited strength of 457 MPa. Notably, the welded sheet exhibited superior mechanical strength compared to the base metal, with ductility demonstrated through a 180° bend test showing no signs of cracking proving its ductility. Microhardness assessments highlighted a decline in hardness within the base metal region (178 HV 0.5 to 186 HV 0.5), contrasting with peak values observed in the weld metal (215 HV 0.5 to 223 HV 0.5). This comprehensive investigation sheds light on the successful fabrication of zircaloy‐2 via tungsten inert gas welding, emphasizing its potential for diverse industrial application.
A Petrov‐Galerkin Dual‐Porosity Framework for Thermal Analysis of Fractured Porous Media
Authors: Taghvaei Mahtab , Khoei Amir R. 
Published: February 2025

ABSTRACTThermal analysis of fractured porous media is of interest in environmental and reservoir engineering. The dual‐porosity method is a common and cost‐efficient approach for modeling fractured domain. In the case of thermal analysis, this method encounters two challenges; the high dependence on the matrix to fracture transfer parameter, “shape factor,” and numerical oscillations produced in the conventional Galerkin finite element formulation for convection dominant problems. To overcome these issues a Petrov‐Galerkin dual porosity (PGDP) algorithm is presented for the analysis of 2D transient heat flow in fractured porous media. In the computational algorithm, an appropriate unit cell is selected from the primary domain and the corresponding thermal shape factor is evaluated with a time‐varying function. Unlike conventional constant shape factor models, this shape factor accounts for not only the geometry of the blocks, but also the thermal properties of the domain and existing boundary conditions. Several case studies are simulated to investigate the validity and sensitivity of the time‐dependent thermal shape factor to different parameters for square and non‐square blocks. Moreover, the Petrov‐Galerkin formulation is applied to effectively achieve the accurate spatial results for highly convective heat flows. Numerical simulations are performed to study the efficiency and accuracy of the proposed PGDP algorithm for different range of convection and conduction regimes. This study illustrates that the PGDP algorithm efficiently enhances the accuracy of the simulation in modeling of fractured domains, particularly in transient stages. Moreover, the capability of the proposed computational algorithm is demonstrated in modeling square and non‐square matrix formations.
A Qualitative Survey of Mothers' Experiences of Breastfeeding Support at a Family Centre
Authors: Castro Breisy , Johnsson Anette , Karlsson Margareta 
Published: February 2025

ABSTRACTAimThe aim was to describe mothers' experiences of breastfeeding support at a family centre.DesignThe study employed a qualitative approach using a descriptive design.MethodsMothers enrolled at a family centre in western Sweden who used breastfeeding support based on the World Health Organization's 10 steps, were voluntarily selected to participate. Data were collected by an open‐ended questionnaire from May to September 2023 and analysed using inductive qualitative content analysis.ResultsThe results indicated that mothers received support in the form of communication, actions and emotional care at the family centre. Accessible and continuous breastfeeding support was provided, rooted in their experiences during pregnancy and after giving birth. This was achieved through meaningful communication and by gaining knowledge via education with someone attentive to their breastfeeding story. Concrete support was offered, including practical advice and guidance to address breastfeeding challenges. Additionally, the mothers felt respected in their breastfeeding decisions and experienced empathetic, supportive care.ConclusionsBreastfeeding support and guidance are crucial to assisting mothers and respecting their individual needs. Effective support encompasses communication, actions and emotional care, strengthened by collaboration among actors to ensure accessibility and personalised care. The cooperative approach to breastfeeding at the family centre provides health‐promoting and preventive primary care from a family‐oriented perspective.Public ContributionsA total of 31 mothers' participated by answering the open‐ended questionnaire. Their responses contributed significantly to the content of this study.